Rate of metabolism of retinol and retinoic acid-maintained rats after a single dose of radioactive retinol. The half-life and metabolism of vitamin A were determined in a group of vitamin A-deficient retinoic acid supplemented rats after a single dose of 340 mug of [6,7-14C2] retinol. The total daily urinary radioactivity, plotted semilogarithmically as a function of days after injection, revealed three pools for retinol and/or metabolites in the rat: (1) a rapidly declining pool with half-life of 0.75 day; (2) a slowly declining pool with a constant rate of decrease and (3) a pool with a half-life of 13 days which begins at approximately 6 weeks after dose. The total daily fecal radioactivity also indicated three pools with half-lives of 2,28.5 and 11.5 days. The effect of retinoic acid feeding was observed on the fifth day after supplementation, as indicated by a decrease in the total daily urinary radioactivity. Thus, retinoic acid is probably in the metabolic pathway of retinol. The half-life and metabolism time of liver vitamin A in these rats were determined as 7 and 10 days, respectively. The specific activities of liver retinyl esters and retinol determined at different intervals after dose indicated continuous mixing of radioactive retinol with a pool of endogenous retinol. Blood retinol levels indicated normal values at 1 week after dose. However, they decreased at 2 weeks after dose and remained constant until the sixth week. The specific activity of blood retinol did not change indicating rapid equilibration after initial mixing and no further dilution from endogenous source.


Adaptation of rat pancreatic amylase and chymotrypsinogen to changes in diet. This study represents an attempt to determine the effect of dietary protein quality and hypophysectomy on the enzymic adaptability of the pancreas in the rat. The specific enzymes studied were amylase, which was purified by immunologic techniques and chymotrypsinogen (activated), which was isolated by affinity column chromatography. Content and synthesis of each enzyme were accurately determined in relation to total pancreatic protein. When rats were fed a 64% sucrose diet (19% casein), there was a two- to three-fold increase in synthesis of amylase. However, if a poor-quality protein (gelatin, gluten, or zein) was substituted for casein, there was no increase in the synthesis of amylase in response to increased carbohydrate. When rats were fed a 19% sucrose diet (64% casein), there was a significant increase in chymotrypsinogen synthesis. Of the poor-quality proteins, gluten was the only one effective in stimulating synthesis of chymotrypsinogen. Peptides, either free or as part of a protein, were necessary for the stimulation of chymotrypsinogen synthesis. Amylase synthesis in hypophysectomized rats was considerably depressed and unresponsibe to increased carbohydrate. This effect could be partially relieved with hydrocortisone, corticosterone, or thyroxin, but not with growth hormone. Hypophysectomy had little effect on synthesis or content of chymotropsinogen.


Effect of fluoride on the serum lipids of guinea pigs. The effects of fluoride intake on the serum lipids of guinea pigs were determined in animals provided with either high or low levels of fat in their diet and fluoride in their drinking water. Evidence of the difference in fluoride intake were reflected by serum fluoride contents. The results suggest that, in guinea pigs receiving excess dietary cholesterol, an inadequate fluoride intake is reflected in increased serum cholesterol. Fluoride intake also influence the serum triglyceride levels, but the direction of the response was dependent on the amount of dietary fat. Serum free fatty acids and phospholipids were not influenced by fluoride intake.


Effects of the scheduling of meal-feeding at different phases of the circadian system in rats. This study was designed to determine whether or not a number of diverse rhythmic variables in the rat could be synchronized to meal timing. This was tested by restricting the availability of food; once during each 24-hour period an unrestricted quantity of food was made available for a 4-hour period to four different groups at different phases of the light-dark cycle, and the rhythms of the variables studied in the different groups were compared. Liver glycogen and serum glucose did synchronize to or were strongly influenced by feeding schedules; corticosterone and the several enzymes measured seemed to reflect an interaction of both the restricted feeding schedule and the light-dark cycle. The mitotic index in the corneal epithelium in all groups remained remarkably synchronized to the light-dark cycle and was altered only minimally by restricted meal timing. All groups on restricted feeding schedules gained less weight than the group fed ad libitum and maintained on a light-dark cycle. These studies caution against assuming that all body functions react in the same manner to different synchronizers; and they emphasize that one must not generalize about the synchronizing effect of meal-timing or even the light-dark cycle.


Effect of prenatal protein deprivation on fetal and neonatal thyroid morphology in the rat. Morphogenesis of the thyroid was compared in young of control and protein-deprived rats from day 17 of gestation through the first postpartum day. Examination of histological sections revealed a significant delay in follicle formation and a reduction in gland area, follicle number, colloid space and cell size in the thyroid tissue of fetal and neonatal pups of protein-deprived dams.


Embryonic loss and progesterone metabolism in rats fed a high energy diet. To elucidate the mechanism of the reduction of embryonic loss due to an increase of dietary protein level in rats fed a high energy diet, the relationship between embryonic loss and progesterone metabolism was investigated in rats fed high energy diets (digestible energy: about 5 kcal/g) differing mainly in casein and starch contents. The embryonic loss was minimum in rats fed a relatively high protein-low starch diet (30% protein-19% starch) and maximum in rats fed a very high protein-very low starch diet (39.9% protein-2.5% starch). On the basis of measuring urinary pregnanediol and in vivo conversion from progesterone to urinary pregnanediol and in vivo conversion from progesterone to urinary pregnanediol in each group, the production of progesterone in the body was shown to vary. In vitro studies showed that the mechanism responsible may involve inhibition of progesterone synthesis by the ovary in the presence of a very high protein-very low starch diet.


Studies of the utilization of high and low erucic acid rapeseed oils by the chick. Experiments were conducted to compare energy utilization, growth and tissue composition of chicks fed diets containing 10 or 20 parts of either high erucic acid rapeseed oir 24 days. Results showed that chicks fed diets containing 10 or 20 parts LER grew at the same rate, utilized energy just as efficiently, had similar heart to body weight ratios and levels of heart lipids equal to or less than chicks fed comparable diets containing SFO. The substitution of 10 or 20 parts HER for an equienergetic amount of SFO depressed gorwth, feed consumption and carcass fat deposition but had no effect on level of cardiac lipid or relative heart size when fed from 4 to 11 days of age. When fed from 4 to 25 days of age, chicks fed 20 parts HER grew slower, consumed less feed, and when pairfed, deposited less carcass fat, utilized energy less efficiently, had increased heart to body weight ratios but a lower level of cardiac lipid than chicks fed comparable diets containing SFO. Irrespective of the type of rapeseed oil or of the age of the chick, heart lipids contained less erucic acid than carcass fat, indicating that chick heart is as capable of disposing of erucic acid as carcass tissue. It was also found that irrespective of the diet fed, a greater percentage of erucic acid appeared to be oxidized than of eicosenoic acid.


Effects of vitamin B-6 deficiency and tryptophan loading on urinary excretion of tryptophan metabolites in mammals. The effect of vitamin B-6 deficiency on excretion of tryptophan metabolites was compared in rats, guinea pigs, hamsters, and humans. With adequate vitamin B-6 intake, a high percentage of the tryptophan administered was excreted as kynurenic acid and quinolinic acid in rat urine, and as acetylkynurenine and kynurenine in hamster urine. None of the tryptophan metabolites measured in normal guinea pig urine or human urine accounted for more than 1% to 2% of the tryptophan administered. During vitamin B-6 deficiency, the percentages of the tryptophan load excreted as xanthurenic acid, kynurenine, and o-hydroxykynurenine, (which precede the 3-hydroxykynureninase step in the kynurenine pathway) were increased in all four species. However, the percentages excreted as 3-hydroxyanthranilic acid and quinolinic acid, which are beyond the 3-hydroxy-kynureninase step, responded differently. The 3-hydroxyanthranilic acid percentage was not changed in rat urine, but was increased in human and guinea pig urines. The quinolinic acid percentage was decreased in rat urine, unchanged in guinea pig and hamster urine, and increased in human urine. In rats, depression of 3-hydroxykynureninase activity was apparently the major factor causing a change in the pattern. However, in hamsters, kynurenine hydroxylase and o-hydroxykynureninanse activities apparently were depressed. In humans, 3-hydroxykynureninase activity also was apparently depressed and the total amount of administered tryptophan accounted fro in the urine as metabolites of the kynurenine pathway was increased. Levels of urinary metabolites reached a maximum in guinea pigs after only 1 week of consuming the vitamin B-6 deficient diet, suggesting that the vitamin deficiency developed very rapidly in this species.


Effects of dietary lipids, dietary protein and environmental temperatures on growth, feed conversion and body composition of channel catfish. Studies were conducted to determine the effects of several lipid supplements in practical-type diets for channel catfish (Ictalurus punctatus) fingerlings reared at 23 degrees and 28 degrees. Maximum growth and feed efficiency were obtained when diets were supplemented with 9% animal tallow, 9% menhaden oil or a combination of the two (4.5% of each). A growth suppression was observed when fish were fed a diet containing a combination of 3% corn oil, 3% animal tallow and 3% menhaden oil. In studies on interactions of dietary protein and lipid at 23 degrees and 28 degrees, increasing dietary protein from 25% to 35% resulted in higher gains. At 28 degrees, increasing dietary lipid from 5% to 12% resulted in increased gains with diets containing 35% protein but not withdiets containing 25% protein. At 23 degrees, 5% lipid was sufficient in all cases. Carcass lipid levels increased with increasing temperature and were positively correlated with weight gains and negatively correlated with carcass moisture content. Improved protein conversion (protein fed: protein gained) was noted when dietary protein levels were increased from 25% to 35%; when dietary lipid levels were increased from 5% to 12%; and when environmental temperature was increased from 23 degrees to 28 degrees.


Effect of dietary amino acids, casein, and soybean trypsin inhibitor on pancreatic protein secretion in rats. Pancreatic enzyme output in response to various purified diets was studied in rats surgically prepared so that pancreatic secretion could be continuously collected, assayed and returned to the intestine. Intraduodenal infusion of phenylalanine and tryptophan alone did not stimulate secretion. Diets containing phenylalanine, tryptophan, a mixture of amino acids, or hydroxyzed casein, fed intragastrically, evoked a small pancreatic response that was similar to the response to a protein-free diet. intragastric infusion of a diet containing 18% casein stimulated a large initial secretion of enzyme that remained elevated throughout the 5.5 hour experiment. Addition of soybean trypsin inhibitor (SBTI) to the diet increased the pancreatic response over that due to dietary casein alone. When pancreatic juice was diverted from the intestine, the large pancreatic responses to casein or to casein + SBTI were greatly reduced and the response was similar to that of the protein-free diet.


Amino acid fortification of wheat diets fed at varying levels of energy intake to rats. The effects on growth and nitrogen utilization of protein quality improvement of white bread fed under varying degrees of adequacy of food energy have been studied. Weanling rats were fed white bread bread plus lysine, and bread plus lysine plus threonine at energy levels ranging from 55% to 100% of ad libitum consumption. Weight gain, protein efficiency ratio (PER), net protein ratio (NPR), and net protein utilization (NPU) were measured and plotted against food consumption. The improvement in growth and nitrogen utilization resulting from amino acid fortification of bread, even when food intake was little more than half ad libitum consumption, was significant. For example, the NPR and NPU values obtained with lysine fortified bread fed at 70% of adlibitum consumption were 1.5 to 2 times those obtained with unfortified bread in spite of the fact that the latter rats consumed 25% more food energy. The implications of these findings for practical problems in human nutrition are discussed.


Energy utilization of a low carbohydrate diet fed genetically obese rats and mice. Genetically obese Zucker rats, ob/ob mice and non-obese littermates were fed low carbohydrate (2%, 48%, and 50% of energy as carbohydrate, protein, and fat, respectively) and control (60%, 19%, and 21%, as carobhydrate, protein, and fat) diets. The oxidation of the energy components of these diets was measured by adding D-[U-14C]glucose, L-[U-14C]glutamic acid, and glyceryl tri-[1-14C]oleate to test meals given intragastrically and collecting respiratory CO2 for 4 hours. The animals responded to the low carbohydrate diet by oxidizing less glucose and more glutamic acid, but these amounts were proportional to dietary carbohydrate and protein composition, In contrast, the animals oxidized both higher amounts and percentages of glyceryl trioleate when fed the low carbohydrate diet. Obese Zucker rats oxidized less fat than non-obese rats when fed both diets, while obese mice oxidized fat to the same extent as non-obese mice. Feeding the low carbohydrate diet significantly increased body weight in the obese mice, but not in obese rats and non-obese mice and rats. The effect of obesity and the low carbohydrate diet on food intake, serum glucose and lipid values and CO2 production are also reported.


Biotin deficiency in the cat and the effect on hepatic propionyl CoA carboxylase. Biotin deficiency was produced in growing kittens by feeding a diet containing dried, raw egg white. After receiving either an 18.5% egg white diet for 25 weeks, or a 32% egg white diet for 12 weeks, they exhibited dermal lesions characterized by alopecia, scaly dermatitis and achromotrichia, which increased in severity with the deficiency. Females developed accumulations of dried salivary, nasal and lacrymal secretions in the facial region although a male did not. There was a loss of body weight in all cats as the deficiency progressed. Hepatic propionyl CoA carboxylase activities were measured on biopsy samples of liver during biotin deficiency and after biotin supplementation. In the deficient state, activities were 4% and 24% of that following biotin supplementation. Propionyl carboxylase activity in the liver of the cat was comparable to that reported in the rat and chick in the deficient and normal states. Subcutaneous injection of 0.25 mg biotin every other day while continuing to receive the egg white diet caused remission of clinical signs, a body weight gain and increased food intake.


Human protein requirements: a long-term metabolic nitrogen balance study in young men to evaulate the 1973 FAO/WHO safe level of egg protein intake. Six Caucasion male MIT students, age 19 to 23 years, were given a formula diet providing 0.59 g egg protein/kg body weight/day and energy intakes approximately 10% above their usual requirements. Four subjects continued on this diet for 81 to 89 days, but for the two the protein intake was increased after 50 and 59 days because of an excessive rise in serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels. The elevated serum AST and ALT activities fell to normal rapidly when these subjects received a diet providing 1.5 g protein/kg/day  from skim milk powder. Body weight increased in five of the subjects. Four showed cumulative negative N balances, and all showed a net loss of total body 40K, which was significant in three. These findings indicate that the 1973 FAO/WHO "safe level" of egg protein intake of 0.57 g/kg is not sufficient for long-term maintenance of most healthy young men. Moreover, the greater N losses calculated from 40K and creatinine measurements than from the N balance data suggest an integumental N loww approximating 15 mg/kg rather than the 5 mg of the 1973 allowances.


Variegated color sensations from rod-cone interactions: flicker-fusion experiments. Multicolored images were produced by the combination of two different color-separation images, one illuminated with 656 nm light and the other illuminated with 500 nm light. Flicker-fusion frequency measurements were used to identify the conditions in which the 500 nm light was below cone threshold. Under those conditions the multicolored images were shown to be generated by rod and long-wave cone interactions.


Segmental dilatation of the ileum.

Segmental dilatation of the ileum. Three new cases of congenital segmental dilatation of the ileum are presented and added to 12 cases of segmental dilatation found in the literature. The aspect of the condition which is of particular interest is the presence in 3 of the dilated segments of heteroplastic foregut derivatives of unusual varieties. The etiology of the condition is discussed; it does not appear to be a single distinct pathological entity.


Early diagnosis and surgical treatment of children with congenital vascular rings and accompanying heart lesions. Methods of early diagnosis, operative treatment and postoperative care are described in children with congenital vascular rings. The ring types were grouped according to Cooley's classification. Among 42 recognized vascular rings 34 children required surgical treatment because of severe or noticeable compressive symptoms of esophagus and trachea. In the postoperative period early respiratory care is especially important.


Open heart surgery in the first six months of life. Intracardiac repair of a variety of cardiac anomalies was performed in 104 infants aged 10 days to 6 mo, presenting with severe hypoxia and/or intractable heart failure. Thirty-eight patients (33 less than three mo of age) did not survive the operation or died during the first postoperative month. Above 6 mo of age, correction of heart defects is often carried out on an elective basis, and results are more favorable. A more convenient choice between corrective and palliative procedures is suggested to achieve better results in the difficult group of patients who require surgery within the first 6 mo of life.


A histopathological study of the remnant of extrahepatic bile duct in so-called uncorrectable biliary atresia. Histopathological study of the remnant of extrahepatic bile ducts in 40 cases of so-called uncorrectable biliary atresia, upon which we operated the last three years, has been performed. The histological findings of the remnant were classified into three types. Only two cases were found to have type 1a ducts in the porta hepatis area, from which we can expect better prognosis postoperatively. We also found that as the patients become older, the size of the duct in the remnant becomes smaller and the hepatic fibrosis becomes more remarkable. Therefore the operation should be performed in the infant with this lesion as young as possible. As for the evaluation of operative results of hepatic portoenterostomy for this lesion, a proper evaluation can be made only in those cases in which a microscopic examination of the remnant of extrahepatic bile duct at the porta hepatis area has been adequately performed. Concerning the pathogenesis of biliary atresia, we presume that congenital abnormalities of bile ducts are a basic factor, and additional nonspecific inflammation and bile stasis complete its pathological condition.


The results of treatment of anorectal anomalies: a thirteen to twenty year follow-up. The long-term results of low anomalies are excellent, as expected, whether primarily treated by cutback or transplantation. Those of the high anomalies are perhaps better than expected but only achieved after an unacceptably long period of incontinence. Better techniques are still needed for these supralevator deformities. Permanent colostomy also had its problems.


Management of liver trauma in children.

Management of liver trauma in children. The charts of 203 consecutive children undergoing emergency laparotomy for management of an acute liver injury were reviewed. Although drainage was all that was required in the majority of cases, massive hemorrhage, usually arising from disrupted hepatic veins, appeared to demand liver resection (as performed in 17 children, with a mortality of 18%) during earlier years of the survey. Control of exsanguinating bleeding from such liver wounds by packing with viable autogenous tissue (pedicled omentum) subsequently eliminated almost entirely the need for resection. Fatalities resulting from either hemorrhagic shock or loss of liver substance then became relatively rare. Additional significant problems were associated organ injuries, postoperative wound and intra-abdominal sepsis, bleeding diatheses, and late instances of hemobilia. The overall mortality was 6%.


Experimental production of cystic dilatation of the common bile duct in neonatal lambs. A reliable experimental model for the study of cystic dilatation of the extrahepatic biliary system has been produced purely by ligation of the distal end of the common bile duct in the newborn lamb. Six of nine experimental lambs surviving the immediate postoperative period lived for periods ranging from 27 to 40 days. All six developed cystic dilatation of the common bile duct.


Avascular transplantation of small bowel in newborn piglets. Segments of small bowel of newborn piglets were isolated and wrapped in omentum as free autotransplants. After initial necrosis, they regenerate either completely, or at least their muscular layer is restored. As there is a lot of inflammatory reaction in most of the grafts, the conclusion is drawn that either preexisting infection, or autoaggressive reactions are responsible for this. Homografts behave like autografts in the beginning, their structures being restored, but are all rejected by the sixth week. Immaturity of the immunologic system in the newborn may be the reason for this late rejection.


The antibacterial effects of impregnated silastic and its possible applications in surgery. We have made an in vitro preliminary study of the feasibility of incorporating suitable antibacterial agents with medical grade silicone rubber ("Silastic") with reference to the immediate and sustained effects in simulated conditions of use. The results are encouraging and further work is planned. The possible applications of such impregnated Silastic in clinical conditions involving implants of various kinds is discussed.


Extradural hematomas in infants.

Extradural hematomas in infants. This study reports 19 cases of extradural hematomas in infants for their relative frequency in head injury of children, their clinical findings, their particular evolution and the therapeutic problems specific to this age.


Management of children with chronic femoral artery obstruction. Chronic obstruction of the femoral artery in children is a complication of diagnostic angiography, cardiac catheterization and umbilical artery catheterization. We have seen 22 cases and have operated on 7. The indications for operation are claudication, muscle wasting, and shortness of the lower limb. The diagnosis is confirmed by a Doppler profile and the abnormal vascular anatomy demonstrated by angiography via the contralateral femoral artery. We have done 4 ilio-femoral, two femo-femoral and one femoro-popliteal bypass grafts utilizing the long saphenous vein. Results have been good in five, the other two grafts having thrombosed.


"H-type" urethroanal fistula.

"H-type" urethroanal fistula. Stephens and Smith have recently described a urethroanal connection through which urine was passed preferentially into the otherwise normal rectum at the pectinate line. Other authors have reported similar deformities. The term "congenital 'H-type' anourethral fistula" was proposed for this rare anomaly by deVries and Friedland in 1974. In this communication, we describe two examples of the "H-type" urethroanal fistula (Fig. 1). Each patient also had tracheoesophageal fistula. One patient (R.P.), now 11 yr of age, has had successful correction of the anomaly. The other patient (T.McC.), a small premature baby whose uroanal deformity was investigated radiographically, died of sepsis and uremia. The anatomical relationships in this baby were investigated histologically in the autopsy specimen by means of serial sections. From this study, it has been possible to determine the sphincteric anatomy and to suggest a possible pathoembryology of the defect.


Polydisperse particulate solids mixing and segregation: nonstationary Markov chains. The feasibility of analyzing interparticulate translocations within agitated beds of polydisperse particulate solids in terms of Markov chains was investigated. A binary mixture of spherical particles subjected to vertical sine wave vibration is shown to behave in accordance with a nonstationary. Markov chain having singly stochastic transition matrixes. The transition probability elements of such matrixes, calculated from a knowledge of the initial and final occupancy vectors, agree with those estimated using tracer particles. With appropriate restrictions, the former method, based on the solution of simultaneous equations, permits a quantitative evaluation of particle mobilities throughout the bed.


Influence of sunscreening agents on color stability of tablets coated with certified dyes III: FD&C Yellow No. 6. The influence of a protective coating of six sunscreening agents (glyceryl p-aminobenzoate, benzocaine, cinoxate, homosalate, n-octyl salicylate, and amyl salicylate) upon the photostability of FD&C Yellow No. 6 used to color coat tablets was studied. The alcohol film, modified sugar-, and film-coating methods were used to apply the sunscreening agents. Tablets were exposed to 1000 foot-candles of light for various times, after which reflectance measurements and visual observations were recorded. FD&C Yellow No. 6 did not follow the Kubelka-Munk equation. The order of relative stability was FD&C Yellow No. 6 greater than erythrosine sodium (FD&C Red No. 3) greater than FD&C Blue No. 1. The greatest protection against fading was afforded by benzocaine.


Quantitative determination of benzoic acid and salicyclic acid in ointments by high-pressure liquid chromatography. Benzoic acid and salicyclic acid in ointments were analyzed quantitatively by reversed-phase high-pressure liquid chromatography. Both benzoic and salicyclic acids can be assayed in combinations directily without interference from each other or the ointment bases. The method is accurate, simple, and rapid. Excellent results were obtained with three commercial bases.


Effects of aspirin and acetaminophen on fetal and placental growth in rats. Aqueous suspensions of aspirin or acetaminophen (125 and 250 mg/kg/day) were administered orally to pregnant Sprague-Dawley rats on Days 8-19 of gestation Day 20, each rat was sacrificed and the uterus was examined in situ. Each fetal-placental unit was resected and examined. Fetuses from rats given 125 or 250 mg/kg/day of aspirin were shorter and weighed less than those obtained from control rats. In animals receiving the higher dose of aspirin, the placentas were smaller and the number of fetal resorptions was increased. Acetaminophen (250 mg/kg/day) did not affect fetal length or weight or the incidence of resorption. Acetaminophen interfered less with the normal growth of the rat fetus and placenta than did aspirin.


Dihydralazine sulfate analysis using 2-methyl-o-nitropyridine-6-carboxaldehyde. A sensitive, selective colorimetric assay was developed for the quantitative analysis of dihydralazine sulfate. The method is based on the interaction of buffered (pH 4) dihydralazine sulfate with a methanolic solution of 2-methyl-3-nitropyridine-6-carboxaldehyde upon heating to give an orange color. This color can be quantified spectrophotometrically at 450 nm,with a lower limit of detection of 1 mug/ml. The color is stable for at least 24 hr. There is no interference from other drugs likely to be present along with dihydralazine sulfate and common excipients. The method was used successfully for the determination of dihydralazine sulfate in combination with other drugs in different commercial tablets. The developed method was applicable as a stability-indicating assay.


NMR determination of trimethoprim and sulfamethoxazole in tablets and powders. An NMR spectroscopic method for the determination of mixtures of trimethoprim and sulfamethoxazole is described. Spectra are determined in dimethylsulfoxide-d6, containing 1,4-dinitrobenzene as an internal standard. Both synthetic mixtures and commercial formulations were assayed, and the results were compared to those obtained using the BP procedure.


Quick estimation of kinetic parameters for a compartment with exponential absorption rate and first-order elimination rate. Two methods are presented for the quick estimation of kinetic parameters for a compartment with an exponential absorption rate and a first-order elimination rate. The first method is by direct computation from the observed levels of substance in the compartment at times t. 2t, and 3t, where t is arbitrary. The second method uses a numerical table to estimate the parameters from the observed peak level, the time of the peak level (or the time when the level rises to half on the peak level), and the time when the level has declined to half of its peak value. Some approximation equations also are given.


In vitro inhibition of viral DNA polymerase activity by litmomycin. Litmomycin, an antibiotic isolated from Streptomyces litmogenes, is highly active against Gram-positive bacteria and possesses antitumor activity. It inhibited viral DNA polymerase activity in vitro. The amount of litmomycin required to cause 50% inhibition of enzyme activity was 80-100 mug (180-225 nmoles)/ml of reaction mixture. The enzyme inhibition was observed when polyriboadenylate--oligodeoxythymidylate, polydeoxyadenylate-oligodeoxythymidyate, polyribocytidylate-oligodeoxyguanylate, activated DNA, and 70 S RNA were used as templates. Reaction kinetics and the mechanism of enzyme inhibition are discussed. The results  suggest that litmomycin interacts with the template primer and not with the enzyme protein to stop the polymerization process.


Application of salivary concentration data to pharmacokinetic studies with antipyrine. The concentrations of antipyrine in plasma and saliva were equivalent in normal volunteers and in patients with acute viral hepatitis following oral doses of antipyrine. Estimates of clearance, volume of distribution, and half-life made from either plasma or saliva samples were not statistically different in these subjects. Differences in the disposition kinetics of anticted using either plasma or saliva samples.


Application of a convective diffusion model to membrane transport. Studies were carried out on the permeation rate of butambed through a dimethicone membrane. Under conditions of "aqueous diffusion layer control", the permeation rate was accurately described by a mathematical model based on convective diffusion theory. In accordance with model, the rate of permeation from a saturated donor phase was shown to be equal to the rate of dissolution from a pure solid.


Single-dose assay of ferrous ion in pharmaceuticals. A method for assay of the ferrous ion in hematinics or multivitamin tablets is described. The method is based on the spectrophotometric measurement of the chromophore produced by reacting the ferrous ion with the highly specific chelating agent ferrozine. The method is proposed as an alternative to the redox methods in the USP and NF.


High-pressure liquid chromatographic analysis of drugs in biological fluids I. Warfarin. A rapid, sensitive, and specific high-pressure liquid chromatographic (HPLC) method for the quantitative analysis of warfarin in plasma is described. The method involves a single solvent extraction of warfarin and the internal standard form acidified plasma, followed by evaporation and HPLC analysis. The method is sufficiently sensitive and accurate for most pharmacokinetic studies: concentrations between 0.1 and 4.0 mug/ml can be measured with a coefficient of variation of 2-5%. Known metabolites of warfarin do not interfere with the analysis.


Separation and analysis of delta 9-tetrahydrocannabinol in biological fluids by high-pressure liquid chromatography and GLC. High-pressure liquid chromatographic (HPLC) systems were developed to separate quantitatively delta 9-tetrahydrocannabinol from heptane-extractable lipoidal and other endogenous substances in biological fluids. These substances interfered with the quantitation by flame-ionization GLC of the unmodified compound and by electron-capture GLC of the pentafluorobenzoyl derivative. Reversed-phase HPLC elution, with 47% acetonitrile in water, and normal-phase HPLC with 25% chloroform in heptane separated delta 9-tetrahydrocannabinol from 11-hydroxy-delta 9-tetrahydrocannabinol and other monohydroxylated tetrahydrocannabinols. These systems also purified stock solutions of delta 9-tetrahydrocannabinol from accompanying contaminants. The various monohydroxylated tetrahydrocannabinols were resolved from each other in the normal phase, 80% chloroform in heptane. The delta 8- and delta 9-tetrahydrocannabinols were separable in the normal phase with 5% tetrahydrofuran in hexane. The GLC analysis of pentafluorobenzoylated delta 9-tetrahydrocannabinol had a sensitivity of 1 ng/ml of plasma, with an estimated 5% standard error with the developed extraction and GLC procedures. Radiochemical analysis of the HPLC-separated fraction had a sensitivity of 0.2 ng/ml of plasma, with an estimated 2% standard error. There was no significant difference between the liquid scintillation and electron-capture GLC assays of the HPLC-separated delta 9-tetrahydrocannabinol obtained from the plasma of dogs administered the drug. Radiolabeled compounds can be added to plasma samples as internal standards to determine the recovery efficiencies of the several procedures in the analysis of unlabeled tetrahydrocannabinol.


Kinetics of indomethacin degradation I: Presence of alkali. The kinetics of indomethacin degradation were followed in alkaline aqueous solutions at various temperatures between 20.1 and 40.7 degrees. The apparent first-order rate constants were evaluated from log absorbance versus time plots at lambda max 318 nm. The primary salt effect was positive. The rate constant-hydroxide-ion concentration profile was linear with a positive slope, suggesting the following rate law: kobs = k1 [OH-]. The experimental data fit the proposed reaction of degradation, I- + OH k1 leads to products, where I- = mono-dissociated indomethacin species. Activation energies and other related parameters were calculated from Arrhenius-type plots.


Scattered isergonic profiles.

Scattered isergonic profiles. Equations were developed for the geometric analysis of scatter in isergonic profiles as a function of vertical (delta delta H), horizontal (delta delta S), and perpendicular (d) distances from the error line. Sigma (sigma-) correlates with each of these quantities of the test series to produce stastistics (F and r) identical to those for correlation with delta G. The vertical distances, delta delta H, are shown to be identical to the substituent effect, beta delta G; thus, it is concluded that the Hepler approach of implicating a solvation  mechanism on the basis of rho-beta correlations for these distances is not warranted. The uncertainty of points on the isergonic profile for the test series was determined using the joint confidence region ("error contour") approach. Statistical limits of the contour lengths overlapped extremely between members of the test series. To eliminate such overlap for series showing small ranges in substituent effects, extremely precise rate data would be required with N (number of data points) = 4 or 5 for the Arrhenius fits . A comparison between d values and the perpendicular half-widths (w/2) of the error contours resulted in d greater than w/2 for each member of the test series (excluding H), providing that scatter in the profile could not result from experimental error. A further comparison between differences in d, delta d, from suggested beta lines for solvation and w/2 values showed that a beta range as large as 45 degrees could be included in the error contour widths of the test series. Since the average reaction temperature, T, fell within this range solvation effects could not be distinguished statistically from error effects.


Solubility profiles and thermodynamics of parabens in aliphatic alcohols. The solubility of a series of compounds was determined in a wide polarity spectrum of normal aliphatic alcohols over a limited temperature range. The solutes chosen were the methyl through n-butyl p-hydroxybenzoates, several of these being useful preservatives. Solubility profiles were determined for these compounds, and the effect of temperature upon their solubility behavior was investigated. The solubility of the solutes is expressed in several concentration notations; mole fraction plots showed a variable twin peak array as a function of the dielectric constant for the solutes studied. Since heats of fusion were available and data were generated as a function  of temperature, thermodynamic parameters for these systems could be calculated. The relationship of these parameters to multiple solubility peak array is discussed.


Fluorocarbon aerosol propellants XI: Pharmacokinetics of dichlorodifluoromethane in dogs following single and multiple dosing. A three-compartment open model was proposed for the disposition of dichlorodifluoromethane in dogs with average half-lives of 1.47, 7.95, and 58.5 min for the three disposition phases. This proposal is contrary to several studies that monitored blood levels for a shorter period. An analysis of the tissue compartment distribution following a single dose showed that about 1.5 hr was required to achieve pseudodistribution equilibration, following which more than 90% of the dose remaining in the body was retained in the tissue compartments. The pulmonary clearance and volumes of distribution were calculated considering the first-pass effect through the lungs. The volume of distribution after reaching pseudodistribution equilibrium was approximately 10 times the body weight in terms of the blood concentration, and about 68% of the propellant was cleared from the blood passing through the lungs in each cycle. Disposition of the propellant followed dose-independent kinetics after multiple dosing. No volatile metabolites were detected in the blood using GC.


Distribution and pharmacokinetics of triamterene in rats. The tissue distribution of 14C-triamterene was examined in the fact. After intravenous administration of 14C-triamterene, high concentration ratios between tissues and blood were found in most tissues except the brain, fat, and testes. The maximal concentration of the drug was in the kidneys, liver, heart, lungs, and skeletal muscle within the first 20 min, when the maximal natriuresis was observed. No metabolite of triamterene was detected in these tissues. The pharmacokinetics of 14C-triamterene also were investigated. The volume of distribution of the drug was greater in the central compartment (60% of the dose) than in the peripheral compartment (40%). The binding of the drug to skeletal muscle is responsible for the fraction of the dose in the peripheral compartment. Rate constants indicate that slow elimination of triamterene is related to its binding to tissue in the central compartment.


Effect of sodium salicylate on renal elimination of a quaternary ammonium compound. Administration of sodium salicylate inhibited elimination of the tetraethylammonium ion in rats. A two-compartment open model was used to describe plasma decline of tetraethylammonium bromide administered intravenously. The rate constant describing elimination from the central compartment was decreased by 25 and 40% in rats predosed with sodium salicylate at 30 and 50 mg/kg, respectively. Salicylate also enhanced the distribution of the tetraethylammonium ion to the peripheral compartment. Urinary excretion is the principal route of elimination for the tetraethylammonium ion, and studies of the effect of sodium salicylate on the uptake of the tetraethylammonium ion by rat renal cortical tissue indicated noncompetitive inhibition by salicylate.


Sustained-release applications of montmorillonite interaction with amphetamine sulfate. Urinary recovery studies showed that montmorillonite significantly affects the initial therapeutic levels of amphetamine sulfate. The combination of a 1:20 drug-montmorillonite complex with pure drug in a 1:1 ratio, based on amphetamine content, resulted in recovery profiles resembling those obtained from prolonged-release dosage forms. The 1:20 complex, pure drug, and combination formulations showed comparable bioavailability after 48 hr.


Mass screening and confirmation of codeine and morphine in urine by radioimmunoassay-GLC. A rapid, sensitive, and specific procedure is described for the mass screening and confirmation of codeine and morphine in urine specimens. The method is sensitive to 0.5-mug/ml levels of both opiates in free and/or conjugate forms. The raw urine is screened directly by radiommunoassay, which is reactive to both free and glucuronide forms of codeine and morphine. Specimens that are screened positive are confirmed by GLC using a flame-ionization detector. The opiates are analyzed as their acetyl derivat-ves on two different columns, OV-25 and Poly-A 103. This multiple approach eliminates false positives caused by interfering substances or structurally similar compounds present in the urine.


Quantitative determination of amitriptyline and its principal metabolite, nortriptyline, by GLC-chemical ionization mass spectrometry. A quantitative GLC-mass spectrometry assay was developed for the determination of the tricyclic antidepressant amitriptyline and its desmethyl metabolite (nortriptyline) in human plasma. The assay utilizes selective ion detection to monitor in a GLC effluent the MH+ molecular ions of amitriptyline and nortriptyline generated by isobutane chemical ionization. The procedure, which utilizes deuterated analogs of amitriptyline and nortriptyline as internal standards, requires 1 ml of plasma and can measure 1 ng/ml of amitriptyline and 0.5 ng/ml of nortriptyline. The curves relating the amounts of amitriptyline and nortriptyline added versus the amounts found over a 100-fold range of amitriptyline and nortriptyline concentrations are straight lines with intercepts of approximately zero and slopes of unity. Analyses of plasma samples from three subjects receiving 50 mg of amitriptyline orally, three times a day, gave an average plasma concentration of 115 +/- 42 ng/ml for amitriptyline and 109 +/- 20 ng/ml for nortriptyline. Similar analyses of the plasma of three subjects who had received a single 50-mg oral dose of amitriptyline showed an average maximum plasma concentration of 25 +/- 10 ng/ml for amitriptyline and 10 +/- 4 ng/ml for nortriptyline. Seventy-two hours after adminis-ration, the average plasma amitriptyline and nortriptyline levels were 3 +/- 2 ng/ml, respectively.


Vehicle effects on activity of an anticonvulsant compound. The effect of several lipid and nonlipid pharmaceutical solvents on the in vivo activity of 1-diphenylmethyl-4- [(6 methyl-2-pyridyl) methyleneamino] piperazine (I) was evaluated in the mouse. The intensity of onset and the duration of anticonvulsant activity of the compound were affected depending on th type and form of liquid dosage preparation used. The rate of decline in anticonvulsant activity in the 80-20% response range followed apparent zero-order kinetics. A linear relationship between the observed ED50 and the concentration of sorbitol in the dosage form of I was observed. A reduction in the sorbitol content of the dosage form resulted in a proportional increase in the rapidity of onset and the duration of anticonvulsant activity of I. Emulsification restored both the onset and duration of pharmacological activity, which was virtually arrested when the compound was given orally as a solution in oil.


Use of anemic piglet to assess bioavailability of iron from oral iron preparations. Except for methods using long-lived iron isotopes, there are no reliable means for assessing the bioavilability of iron from oral preparations in human subjects. Use of the anemic piglet as an alternative means was studied. When piglets were made anemic on a commercial milk diet and then dosed with solutions of 1, 2, and 5 mg/kg of ferrous sulfate/day, a dose-related recovery of hematocrit and hemoglobin levels resulted. The most sensitive dose range for use in a bioavailability study of iron was between 1 and 2 mg of iron/kg/day when using these parameters. A study carried out using this method indicated that the iron from a delayed-release capsule and from a ferrous sulfate solution was equally bioavailable. Hemoglobin and hematocrit recovery rates of the anemic piglet were shown to be reliable and sensitive indicators of the bioavailability of iron from various iron dosage forms.


Role of neuronal and extraneuronal uptake in responses of rabbit iris dilator muscle to levarterenol and phenylephrine. The roles of neuronal and extraneuronal uptake mechanisms in the response of iris dilator muscles of rabbit to levarterenol (norepinephrine) and phenylephrine were investigated. Chemical denervation with 6-hydroxydopamine was used to eliminate neuronal uptake. Exposure to corticosterone prior to and during exposure to levarterenol or phenylephrine was used to assess the importance of extraneuronal uptake. Dose-response curves and ED50 values for levarterenol or phenylephrine in control and 6-hydroxydopamine-denervated tissues, both in the presence and absence of corticosterone, are shown. Curves illustrating the decay of tension on washout of levarterenol or phenylephrine from treated tissues were analyzed. 6-Hydroxydopamine denervation affected the response to levarterenol more than that to phenylephrine. Washout of both agonists was slower after 6-hydroxydopamine pretreatment, and washout of phenylephrine was more rapid when corticosterone was present. These data indicate that extraneuronal uptake in iris dilator muscles was more important in determining the response to phenylephrine than to levarterenol and that neuronal uptake was more important in determining tissue responsiveness to levarterenol than to phenylephrine.


Absorption, distribution, and excretion of 14C-meglumine in rats and dogs after administration of 14C-meglumine salicylate. Meglumine labeled with carbon-14 was administered orally as 14C-meglumine salicylate to rats and dogs to study its distribution and excretion. The compound was incompletely absorbed; that which was absorbed was rapidly excreted in the urine. Peak blood levels were about 5-10 mug/ml in rats and 2-8 mug/ml in dogs. Tissue levels were negligible at the end of the experimental periods. No evidence for N-demethylation or oxidation to carbon dioxide was obtained.


The effect of neonatal sympathectomy on the response of the rat submandibular gland to isoproterenol. The right superior cervical ganglion was removed from 1-day-old rat pups. For four consecutive days (22-26 days of age), the rats were injected twice daily with isoproterenol-HCl (IPR) at a dose of 2.0 mg/100 g.b.w. and killed on the 27th day of age. Control animals were injected with the solvent, 0.1% Na2S2O5, according to the same protocol. In both control and IPR-treated rats, fluorescence microscopic examination of glands prepared by the Falck-Hillarp method showed a total absence of adrenergic nerve fibers on the side of sympathectomy, and a normal innervation on the unoperated side, while light microscopic examination of Epon-embedded glands revealed no differences in structure between the noninnervated and intact glands. However, after IPR treatment the noninnervated glands consistently showed greater absolute and relative weight, and total DNA, RNA and protein than the corresponding intact gland from the same animal. It is suggested that this greater hyperplastic and hypertrophic response in the noninnervated gland represents a postjunctional supersensitivity of acinar cells to the beta agonistic action of IPR.


Afterdischarge on postganglionic sympathetic nerves following repetitive stimulation of the preganglionic nerve to the rat superior cervical ganglion in vitro. An asynchronous firing or afterdischarge (AD) was recorded in vitro from the postganglionic internal carotid nerve of the rat superior cervical ganglion following repetitive stimulation of the preganglionic nerve when ganglion transmission was blocked by chlorisondamine, nicotine or hexamethonium, but was rarely observed in untreated ganglia. A stimulus frequency of at least 5 Hz was required to induce AD and as few as 100 pulses caused a significant response. The amplitude and duration of AD varied with the number of pulses. Low calcium solutions resulted in AD in the absence of ganglion blocking drugs, and high calcium solutions or low concentrations of atropine abolished the AD. Increasing magnesium concentration to 10 mM or the manganese concentration to 0.1 mM reduced or prevented AD following preganglionic nerve stimulation. The onset of AD was delayed in potassium-free solutions and at a lowered temperature. Dinitrophenol had a small depressant effect on AD but sodium azide reduced the amplitude significantly. Exposure of ganglia to bethanechol, 300 to 600 muM, resulted in asynchronous firing recorded from postganglionic nerves, and stimulation of the preganglionic nerve transiently depressed the drug-induced firing but enhanced the firing 30 to 60 seconds after the volley. Physostigmine did not alter the amplitude of bethanechol-induced firing after a volley. Prolonged high frequency (40 Hz) stimulation of the preganglionic nerve increased the AD following a 20 Hz test volley for up to 1 hour. It is concluded that increasing the release of acetylcholine or blockade of nicotinic receptors makes more acetylcholine available for interaction with muscarinic receptors, and that stimulation of the preganglionic nerve unmasks or sensitizes ganglionic muscarinic receptors. No clear evidence of a metabolic basis for the muscarinic response was obtained.


Possibilities for a cholinergic action on smooth musculature and on sympathetic axons in brain vessels mediated by muscarinic and nicotinic receptors. A pharmacological identification and characterization of cholinergic receptors was carried out in pial arteries of cats. In one series of experiments, the middle cerebral artery was suspended in an organ bath for recording fo circular motor activity. Parasympathomimetic compounds produced either a relaxation or a contraction. The relaxation occurred at low doses (up to 10(-6) M), and the response was inhibited in a competitive manner by atropine. The mean KB value (determined with acetylcholine as agonist) was 3.85 X 10(-11) M, and the corresponding pA2 value 10.43. At higher doses, the parasympathomimetics produced a contraction. This effect, too, was inhibited in a competitive manner with atropine. The calculated mean KB value with acetylcholine as agonist was 1.12 X 10(-11) M, and pA2 was 10.07. The motor responses did not require an intact perivascular sympathetic innervation, which shows that the effects were mediated by muscarinic type of cholinergic receptors present in the smooth musculature. In another series of experiments, pial arteries were preincubated in the presence of 3H-norepinephrine, and the amount of tritium efflux was measured in a superfusion system before or during electrical field stimulation (12 V, 1 msec pulse duration, 10 Hz). The efflux was minimized by sympathetic denervation, and the effect of transmural stimulation abolished by bretylium and guanethidine, which shows that the bulk of tritium overflow during stimulation originated from the perivascular sympathetic nerves. The marked elevation of tritium efflux during stimulation was enhanced by hexamethonium, and it was inhibited by nicotine and acetylcholine, whose effects were counteracted by hexamethonium (but not by atropine). This finding indicates the presence of nicotinic type of cholinergic receptors on the perivascular adrenergic nerves, allowing inhibition of norepinephrine by acetylcholine that may be liberated from the adjacent cholinergic terminals in the autonomic nerve plexus.


Enhancement of phrenic nerve activity by digoxin: an effect dependent upon intact ninth and tenth cranial nerves. Digitalis increases phrenic nerve activity and causes hyperventilation. To determine whether this effect on respiration is caused by central drug actions on brainstem respiratory neurons or by peripheral drug actions which increase excitatory afferent drive to central respiratory neurons, digoxin was administered intravenously to cats with or without intact IXth and Xth cranial nerves. Digoxin caused marked increases in phrenic nerve activity in cats with intact afferent cranial nerves, but it had no effect in cats with severed afferent nerves. This suggested that effects of digoxin on respiration depend upon afferent input to respiratory neurons. However, digoxin may have had subliminal effects on central neurons which increased phrenic activity only in the presence of excitatory input. To test this possibility, effects of intravenously administered digoxin were observed on centrally evoked submaximal responses in the phrenic nerve. Subarrhythmic, arrhythmic or lethal doses of digoxin had no effect on excitatory phrenic responses evoked from the pons. Thus, effects of digoxin on phrenic nerve activity appeared to be due primarily to drug actions on peripheral neural sites which had excitatory influences on respiration.


Effects of perhexiline on survival time and infarct size in experimental myocardial infarction. The effects of perhexiline on survival time and infarct size were studied in three animal models. Dogs pretreated orally with perhexiline, 200 mg/day/14 days, and monitored under anesthesia for 30 hours after ligation of the left anterior descending coronary artery (LAD) had infarct weights of 9.1+/-1.9 g as compared to 15.2+/-1.0 g in paired untreated controls (P less than .02). Twelve of 15 perhexiline-pretreated dogs survived the duration of these studies while only 5 of 15 control animals survived for the same period of time (P less than .05). Serum creatine phosphokinase activity was significantly lower in the treated dogs at 9, 12 and 15 hours after ligation (P less than .05). Conscious dogs, pretreated orally with perhexiline 200 mg/day/7 days or 400 mg/day/7 days and monitored without anesthesia or analgesia for 72 hours after coronary ligation had smaller infarcts (P200=26+/-5; P400=26+/-4; C=39+/-5 g; P less than .05) lower plasma peak creatine phosphokinase activity (P less than .05) and reduced heart rate (P400=198+/-8; C=226+/-8 beats/min; P less than .05) and reduced incidence of ventricular ectopic beats (P less than .05). In pentobarbital anesthetized open-chest dogs, perhexiline (3 mg/kg i.v.) reduced the sum of S-T segment elevation after left anterior descending coronary artery occlusion from 32+/-3 to 14+/-1 mV (P less than .001); this effect was associated with and/or preceded by a reduction in arterial pressure (101+/-4 to 78+/-5 mm Hg; P less than .001) and heart rate (151+/-8 to 138+/-7 beats/min P less than .025; Circumflex flow increased from 38+/-4 to 83+/-8 ml/min (P less than .01). In noninfarcted open-chest dogs, perhexiline administration (3 mg/kg i.v.) resulted in increases in coronary blood flow, narrowing of arterial-coronary sinus O2 difference and a 14% reduction in myocardial O2 consumption. The protective effects of perhexiline on the ischemic myocardium appear to result from reductions in heart rate and associated decrease in myocardial O2 demand as well as an antiarrhythmic effect.


The effect of inotropic agents on glycerol release and protein kinase activity ratios in the isolated perfused rat heart. Glycerol release was employed as an index of endogenous glyceride hydrolysis in rat hearts perfused by a Langendorff technique with Krebs-Henseleit-bicarbonate buffer containing 5.5 mM glucose. Changes in cardiac contractility induced by glucagon, isoproterenol, epinephrine and ouabain were associated with an increase in glycerol efflux from the heart in a dose-dependent fashion. Propranolol, a beta adrenergic blocking agent, markedly diminished the increase in glycerol release due to isoproterenol without affecting this same parameter subsequent to glucagon or ouabain infusion. Insulin, a potent antilipolytic agent in adipose tissue failed to diminish glycerol efflux elicited by any of the inotropic agents studied. Protein kinase activity ratios were employed as an index of cyclic adenosine 3':5'-monosphate levels. Increases in cardiac contractility and glycerol efflux induced by isoproterenol and glucagon were associated with increases in protein kinase activity ratios while increases in contractility and glycerol efflux induced by ouabain were not accompanied by an increase in protein kinase activity ratios.


The cardiovascular pharmacology of the antibiotic ionophore Ro 2-2985 (X537A). Ro 2-2985 increased mean arterial blood pressure in both the venous bypass preparation and the intact animal; however, total peripheral resistance increased in the venous bypass preparation with a constant cardiac output but decreased in the intact animal with an increase in cardiac output. These observations indicate a drug-related increase in the distensibility of the aorta at the same arterial pressure. In vivo ventricular function curves were shifted to the left indicating enhanced myocardial performance with the translocation of large volumes of blood to the central circulation since total body venous compliance was significantly decreased. Beta adrenergic blocking doses of propranolol blocked the positive inotropic effect of Ro 2-2985 while myocardial depression produced by toxic doses of propranolol was reversed. This observation suggests several mechanisms for the Ro 2-2985 metabolic mediation of myocardial muscle contraction. The cardiovascular effects produced by Ro 2-2985 were accompanied by a marked polycythemia and a decrease in plasma volume without a change in total circulating blood volume, while blood glucose values showed a nonsignificant increase. Ro 2-2985 produced a marked increase in cardiac output. The increase in myocardial performance appears to be complex since myocardial force of contraction, dT/dt, dP/dt:P40 and Vmax were all increased. RO 2-2985 increased coronary flow without an increase in resistance. There were no significant increases in myocardial arteriovenous glucose, lactate, K+, Ca++, Na+ or Cl.


Pharmacokinetics of morphine by radioimmunoassay: the influence of immunochemical factors. Two radioimmunoassays (RIA-A and RIA-B) were used to estimate morphine equivalents (ME) in rabbit serum after i.v. administration of morphine or morphine-3-glucuronide (M-3-G). RIA-A and RIA-B differed only with respect to the particular pool of antibodies used, and both were elicited from rabbits immunized with a 2-diazomorphine-protein conjugate. In vitro inhibition studies indicated the molar ratio of M-3-G/morphine which inhibited 3H-morphine-antimorphine binding by 50% (150) was 90 and 14 for RIA-A and RIA-B, respectively. RIA-B 150 values were dependent on the final protein concentration of the incubation mixture. RIA-A and RIA-B estimates of the ME per milliliter were in agreement in serum samples obtained from rabbits after i.v. morphine 0.01 mg/kg; however, after higher doses only samples obtained in the first minutes agreed and at later times RIA-B estimates exceeded RIA-A by increasing amounts. After i.v. M-3-G (1.0 mg/kg) RIA-B estimated 20 to 25 times more ME per milliliter than RIA-A. After rapid i.v. administration of morphine (1 or 5 mg/kg) the disappearance curves obtained with RIA-B were multiphasic and contained a prolonged terminal phase with an estimated half-life of 24 hours. The higher estimates obtained with RIA-B are best explained by cross-reactions with M-3-G or other morphine metabolites. With RIA-A the mean serum morphine clearance (86 ml/min/kg) and half-life of the elimination phase (74 minutes were independent of dosage. The least complicated pharmacokinetic model which describes the disposition of morphine in the rabbit is the open two-compartment model.


First-pass effect of morphine in rats.

First-pass effect of morphine in rats. In order to evaluate the first-pass effect of morphine, the pharmacokinetic parameters of 3H-morphine (5 mg/kg) were studied in male Sprague-Dawley rats by comparing the plasma concentrations after oral, intravenous and intraportal administration. Morphine was almost completely absorbed from the gastrointestinal tract, since no significant difference was found in the cumulative urinary excretion of radioactivity after intravenous and oral administration. Route of administration had no affect on plasma half-life (about 115 minutes) of unchanged morphine. In contrast, the area under the plasma concentration vs. time curve for morphine after oral administration was only about 18%, and after intraportal administration about 40% of that observed after intravenous administration. It can be estimated that approximately two-thirds of the overall first-pass effect (82%) of morphine is due to extraction and/or metabolism in the intestine and the remaining one-third by the liver.


Clofibrate and clofibric acid: comparison of the metabolic disposition in rats and dogs. In rats, equimolar oral doses of [14C]clofibrate and [14c]clofibric acid produced essentially the same profiles of blood levels, tissue distribution and excretion of radioactivity. Both compounds were completely absorbed, and all radioactivity found in the serum was due to clofibric acid (CPIB). Tissues contained readily detectable radioactivity levels, but the concentration was generally lower than in serum. A large proportion of CPIB in liver, heart, kidney, fat and muscle was associated with intracellular space. In rat urine, CPIB was present both free and conjugated with glucuronic acid. Approximately 97% of the serum CPIB was not conjugated. Identical decreases in serum lipids and hepatic cholesterol synthesis were observed in rats treated for 1 week with either compound. In dogs, the serum contained 40% more radioactivity after [14C]clofibric acid than after an equimolar oral dose of [14C]clofibrate; approximately 88% of the serum radioactivity was due to CPIB. Some biliary excretion was detected. The extent of binding to serum protein varied with concentration of CPIB and with the species; the affinity was in the order man greater than dog greater than rat. The results demonstrate that clofibric acid and clofibrate are metabolically and pharmacologically equivalent in rats, but not in dogs. The data are in accordance with the view that the pharmacological activity of clofibrate is due to clofibric acid.


The influence of fasting on the disposition of warfarin in rats. A study was undertaken to investigate the influence of fasting on the disposition of warfarin in rats. Fasting consisted of withholding solid food, but not water, immediately following warfarin (3 or 10 mg/kg s.c.) administration until sacrifice at different time intervals (3, 6, 12, 24 and 30 hours). Control animals were fed ad libitum. Total and unbound warfarin concentrations were measured in plasma and liver supernatant as well as unchanged warfarin and its metabolites in urine. The disposition of unbound warfarin was found to be markedly affected by fasting, especially at the 3 mg/kg dose: the disappearance rate of unbound warfarin from plasma was accelerated in fasted animals in contrast to that of total warfarin. In addition, unbound warfarin was cleared from plasma at a more rapid rate than total warfarin in both control and fasted animals. At the 10 mg/kg dose, the disposition of total and unbound warfarin was little affected by fasting. The concentration of unbound warfarin in the liver supernatant of fasted rats given warfarin, 3 mg/kg, was significantly increased at 6 and 24 hours of fasting. Plasma free fatty acids were significantly elevated starting at 6 hours, but no such difference was noticed with liver homogenate, except at 24 hours. The 24-hour urinary excretion of unchanged warfarin was higher in fasted rats, but fasting failed to produce any change in the excretion of warfarin metabolites. The results of the present investigation indicate that short periods of fasting influence the disposition of unbound warfarin without apparently modifying its biotransformation and further show the importance of plasma protein binding on the pharmacokinetics of warfarin.


Metabolic clearance of furosemide in the rat. The effect of probenecid on the metabolic clerance of [35S]furosemide was examined in Sprague-Dawley rats by the single injection technique. Metabolic clearance was found to decrease from 1.74+/-0.11 ml/min in animals which received furosemide alone to 1.06+/-0.10 ml/min in animals which received both furosemide and probenecid. Estimation of urine and biliary clearance revealed that approximately two-thirds of the metabolic clearance was due to urinary clearance and one-third to biliary clearance, and that both decreased after probenecid administration. Thin-layer chromatographic studies indicated furosemide was metabolized by both liver and kidney but also secreted in unchanged form in urine, and that the proportion of unaltered furosemide to metabolite in urine was increased by probenecid. Further studies indicated that phenobarbital pretreatment had no effect on either hepatic or renal clearance of furosemide and that bile clearance was not altered by acute bilateral nephrectomy.


Diuretic-induced uricosuria: interaction with pyrazinoate transport in man. We investigated the acute effect of an orally administered uricosuric natriuretic agent (SKF-62698) on renal urate transport in paired clearance studies in seven normal men. The participants received SKF-62698 on two separate occasions. Prior to the second study, each received pyrazinamide (PZA) in order to inhibit the tubular secretion of urate. Within 3 hours, SKF-62698 significantly decreased the plasma urate and trebled the rate of urate excretion in the studies without PZA. In contrast, after PZA pretreatment. SKF-62698 did not diminish the plasma urate appreciably and elicited only 60% of the previous increase in urate excretion. Sodium excretion quadrupled after SKF-62698, irrespective of the presence of PZA. Plasma concentrations of pyrazinoate, the renally active metabolite of PZA, were at levels previously shown in the chimpanzee to primarily inhibit the tubular secretion of urate. Therefore, intact tubular secretion of urate probably was necessary in order for SKF-62698 to elicit its maximum uricosuric response. SKF-62698 appeared to inhibit the tubular secretion of pyrazinoate, but the observed changes in urate transport could not be explained on that basis.


Glutathione S-transferases: an evaluation of their role in renal organic anion transport. Organic anion transport capacity measured as accumulation of p-aminohippurate by renal cortical slices was less in kidneys from newborn rats and rabbits than adults and increased with age. Glutathione (GSH) S-aryltransferase activity in 100,000 X g supernatant of renal homogenates, an estimate of GSH-S-transferase concentration in the tissue, was also less in newborn of both species. Enzyme activity increased to adult values by 1 week of age in rats, prior to maturation of transport capacity. Enzyme activity in rabbit kidney was not different at 1 day and 2 weeks but was increased by 4 weeks coincident with transport maturation. In rats, 25 mg/kg of 3-methylcholanthrene administered once a day for 3 days significantly increased enzyme activity but had no effect on transport capacity. Chronic ammonium chloride acidosis increased enzyme activity 8-fold but decreased transport capacity. Forty-eight hours after unilateral nephrectomy in rats transport capacity was significantly increased with little effect on enzyme activity. L-Methionine-SR-sulfoximine (1.85 mmol/kg) significantly reduced glutathione concentration in renal cortex but had no effect on transport capacity. Organic anion transport was greater in male than in in female mice yet there was no difference in enzyme activity between sexes. 3-Methylcholanthrene (10,20, 30 and 40 mg/kg) administered to 2-week-old rabbits twice daily for 3 days increased transport in a dose-dependent manner. GSH S-transferase activity was also increased. Penicillin (90,000 I.U. twice daily for 2 days) similarly increased transport but had no stimulating effect on enzyme activity. The apparent lack of correlation between transport capacity and GSH S-transferase in several instances suggests that GSH S-transferase concentration is probably not the rate-limiting step in renal organic anion transport.


Clearance and micropuncture studies of the effects of a new indanyloxyacetic acid diuretic on segmental nephron function in rats. The renal effects of a new, substituted indanyloxyacetic acid diuretic agent were evaluated in 16 anesthetized rats using micropuncture and clearance techniques. Glomerular filtration rate, mean arterial pressure and hematocrit remained unchanged. Urine flow increased 13 times after i.v. administration of 50 mg/kg b.wt. of the diuretic. Sodium excretion increased from 0.4 +/- 0.05% of the amount filtered to 6.62+/-0.87%. Potassium urine/plasma concentration ratio declined 6-fold while potassium excretion nearly doubled. Proximal tubular reabsorption was not altered significantly by this indanone diuretic. Reabsorption was markedly inhibited between late proximal and early distal micropuncture sites, that is, in the loop of Henle. The diuretic did not appear to interfere with normal distal tubular function. In the collecting tubules, reabsorption was markedly reduced from 41+/-0.2 mul/min/100 g b.wt. to 26+/-5 (with P less than .005). This new indanone compound appears to be a potent, specific natriuretic diuretic agent which inhibits tubular reabsorption primarily in the loop of Henle and collecting tubules, that is, in distal nephron segments located deep within the kidney. It produces a somewhat delayed but prolonged diuresis in the rat.


Diuretics and small intestinal lymph flow in the dog. Simultaneous measurements of thoracic duct lymph flow and small intestinal lymph flow were carried out in mongrel dogs after the administration of mannitol, ethacrynic acid, furosemide and chlorothiazide. Thoracic duct lymph flow increased only after injection of mannitol. Intestinal lymph flow increased after injection of all diuretics except chlorothiazide. Furthermore, mannitol produced simultaneous increases in thoracic duct and intestinal lymph flows. The durations of response of the increased lymph flows from each lymph channel produced by mannitol were statistically identical. The durations of increased intestinal lymph flows observed with each drug were: 40+/-3 (S.E.), 43+/-2 and 38+/-2 minutes for mannitol, ethacrynic acid and furosemide, respectively. Mean arterial blood pressures and inferior vena cava pressures did not change from the control to the experimental state in any animal studied. Similarly measurements of serum and lymph sodium, potassium and protein concentrations were unchanged from the control to the experimental state. These studies demonstrate that mannitol simultaneously increases thoracic duct lymph flow as well as intestinal lymph flow. Secondly, the results suggest that the increases in thoracic duct lymph flow after ethacrynic acid and furosemide administration, observed in previous studies arose primarily from the small intestine.


The protective effect of influenza vaccine in a mixed influenza A and B epidemic in a boys' boarding school. A mixed influenza A and B epidemic, which affected 30 per cent of the boys in a boarding school during the early part of 1976 is described. Virological findings indicate that most cases were due to influenza viruses similar to A/Victoria/75.The incidence of influenza was similar in all blocks in the school, but very variable in the boys' houses. The four-day half-term holiday helped to limit the epidemic.Eighty-six per cent of the boys had received an influenza vaccine containing the A/Scotland and A/Port Chalmers antigens.Influenza vaccination was of definite value, giving a protection rate among vaccinated boys of 36 per cent. Vaccinated boys who developed influenza had a shorter illness than unvaccinated boys.


How do we cope with death?

How do we cope with death? We hope that general practitioners will consider counselling their dying patients more actively, including those in hospital where terminal care may be poorly handled psychologically. This entails a major change in training which we hope is taking place through vocational training schemes. We feel a change in attitude to be necessary by many general practitioners who often deal with death by evasion and untruth.


Hormonal and follicular factors affecting maturation of sheep oocytes in vitro and their subsequent developmental capacity. Oocytes removed from, or retained within, non-atretic and atretic follicles of different sizes were cultured for 24 h in the presence of a variety of hormones in an attempt to identify the factors affecting oocyte maturation in vitro. Resumption of meiosis was assessed morphologically; the developmental capacity of oocytes after culture was determined by transfer to the oviducts of inseminated ewes. About 70% of oocytes cultured after removal from follicles of different sizes resumed meiosis in vitro, but they did not undergo normal development after transplantation. Oocytes cultured within the follicle in hormone-free medium remained at the germinal vesicle stage. In the presence of FSH and LH some oocytes reached the second meiotic metaphase: 19% in small (2-3 mm diam.) and 73% in larger (3-5 mm diam.) non-atretic follicles, and 54% in small and 45% in larger atretic follicles. Less than 5% of oocytes cultured in follicles developed into normal blastocysts after transplantation when either no hormone or only FSH and LH were added to the culture medium. The addition of oestradiol-17beta to medium containing FSH (2 mug/ml) and LH (1 mug/ml) resulted in the development to blastocysts of 26% of oocytes from small non-atretic follicles, 46% from large non-atretic follicles and 50% from atretic follicles. Blastocyst formation was greatly depressed and fragmentation rate signinificantly increased with concentrations of 10 mugFSH/ml and 2 mug LH/ml. Developmental capacity after culture was further demonstrated by the birth of lambs from 63% of blastocysts derived from oocytes matured in vitro; 52% of control blastocysts developed to lambs after transfer.


Ovarian asymmetry in the shrew, Crocidura russula monacha. The total number of corpora lutea developed in the left and right overies of 170 white-toothed shrews (Crocidura russula monacha) differed significantly, showing a functional dominance of the left ovary. Blastocytes were equally distributed in both uterine horns.


Increasing uterine response to vaginal distension during late pregnancy in sheep. Intrauterine pressure changes were monitored in 5 pregnant ewes and uterine venous prostaglandin (PG) F concentrations were determined after distension of the vagina. Uterine contractility and utero-ovarian PGF concentrations were elevated by vaginal distension and the magnitude of both effects increased as parturition approached.


Stimulation of testicular protein synthesis in vivo by gonadotrophins and growth hormone in hypophysectomized adult mice. The effects of FSH, HCG, GH and testosterone on testicular protein synthesis were investigated in hypophysectomized adult mice by measuring the incorporation of tritiated lysine into acid-precipitable material. The incorporation per mg protein was increased by FSH, HCG and GH but decreased by testosterone. The maximum effect of FSH occurred at between 8 and 14 h after administration of the hormone, much later than found in vitro for the rat.


Ultrastructural observations of the incorporation of guinea-pig spermatozoa into zona-free hamster oocytes. Zona-free hamster oocytes inseminated in vitro with acrosome-reacted guinea-pig spermatozoa were examined with the electron microscope. Guinea-pig spermatozoa, in the vicinity of the oocytes, consistently lacked the whole acrosome including the equatorial segment region. In cross fertilization sperm-egg membrane fusion does not differ significantly from that of normal fertilization. However, it was sometimes possible to observe protrusions of oocyte cytoplasm containing sperm chromatin in the process of dispersion.


Correlation between ultrastructure and biochemical changes in the testis of the American grey squirrel, Sciurus carolinensis, during the reproductive cycle. Distinct differences in tha ability of isolated seminiferous tubules and interstitium to utilize steroid precursors for androgen production in vitro were observed during the reproductive cycle of the American grey squirrel, Sciurus carolinensis. In spermatogenically active testes, the seminiferous tubules and the interstitium readily synthesized androgens from labelled C21 steroid precursor; seminiferous tubules also produced significant amounts of 17alpha,20alpha-dihydroxyprogesterone. However, during sexual regression androgen synthesis was drastically reduced in both testicular components, while the production of 20alpha-reduced metabolites of progesterone and 17alpha-hydroxyprogesterone was increased. Many of the fine-structural changes occurring in Leydig and Sertoli cells during the reproductive cycle could be correlated with the capacity of isolated seminiferous tubules and interstitium to formulate androgens from labelled precursors.


Fine structure of Leydig cells in crabeater, leopard and Ross seals. Ultrastructural study of the Leydig cells of nonbreeding crabeater, leopard and Ross seals showed that three types of cells could be distinguished. Type I cells possessed the cytological features typical of steroid-secreting cells. Type II cells exhibited various features of degeneration, e.g. accumulation of large amounts of lipofuscin granules (residual bodies), lipid droplets, secondary lysosomes, rectangular crystalloids, and previously undescribed 'peculiar bodies'. These cellular inclusions and debris were released into the interstitium to be phagocytosed by macrophages and/or resorbed by the lymphatics. Type III Leydig cells contained large amounts of lipid droplets, sparse cytoplasmic organelles and essentially became lipid storage cells.


Receptor activity of the hamster and mouse solubilized zona pellucida before and after the zona reaction. Capacitated golden hamster spermatozoa bound to the inner wall as to the outer surface of the zona pellucida, suggesting that the receptor-for-spermatozoa may occur throughout this egg envelope. When solutions of hamster zonae pellucidae were prepared by heating zonae in an aqueous buffer, receptor activity was retained and was stable to boiling. The addition of such solutions to capacitated spermatozoa (5 zonae/mul) prevented them from binding to eggs and fertilizing them. Solubilized mouse zonae were also partly effective, as would be predicted from the limited crossbinding between mouse and hamster gametes. Receptor activity was lost following the zona reaction.


Differentiation of decidual cells in cultures of rat endometrium. Endometrial scrapings were collected from rat uteri at various times (0-4 days) after induction of a decidual reaction by i.p. injection of pyrathiazine hydrochloride (20 mg/animal) on the 5th day after a sterile mating. The tissue was dissociated by treatment with trypsin and the cells were cultured as monolayers. The differentiation of decidual cells was followed in these cultures. Two morphologically distinct cell populations were recognized: (i) dispersed spindle-shaped or stellate cells, and (ii) colonies of closely packed polygonal cells, first apparent after 48 h in culture. During culture, [3H] thymidine was incorporated into the nuclei of both cell types, as indicated by autoradiography. There was an increase in the number of cells in the colonies as culture progressed; most mitotic figures and the highest % of labelled nuclei were located within the colonies. Bi- and multinucleated cells, which are a characteristic feature of decidual tissue in vivo, appeared in the colonies on the 3rd day of culture and constituted about 60% of the colony population after 4-5 days. The dispersed cells showed a doubling in nuclear area during 4 dyas in culture, suggesting the formation of polyploid cells; such cells are prominent in fully differentiated decidual cells in vivo. The content of prostaglandin E in the cultured cell, determined by radioimmunoassay, was about 15-fold higher than that in rat embryo fibroblast cultures grown under similar conditions, and was comparable to the level of prostaglandins found in decidual cells in vivo.


Reproductive function in prepubertal lambs: ovulation, embryo development and ovarian steroidogenesis. When 23 10-16 week-old Welsh Mountain lambs were treated with PMSG 19 ovulated, the number of eggs ovulated being directly correlated with the duration of progesterone pretreatment (0-5 +/- 0-29 (S.E.M.) after 3 days; 7-8 +/- 3-47 after 18 days). Injection of HCG at the time of the induced oestrus had no effect on ovulation. The eggs shed from immature ovaries became fertilized and developed normally when tested in the ligated rabbit oviduct for development to the morula stage and by transfer to adult ewes (1 live lamb). Luteal function in lambs with a single CL was similar to that in nonpregnant ewes; progesterone levels in entire lambs with multiple CL and in hysterectomized lambs remained elevated for at least 60 days. The capacity of ovarian follicles from PMSG-primed lambs to secrete oestrogen, testosterone and progesterone in vitro was similar to that of follicles from adult ewes. However, oestrogen production by lamb follicles immediately after explantation was higher than that of adult follicles and the administration of progesterone to lambs before PMSG treatment decreased subsequent follicular testosterone production.


Fluid reabsorption in the isolated duct of the rat cauda epididymidis. A technique is described fro measurement of rate of fluid reabsorption in a segment of the rat cauda epididymidis in vitro. The basal rate was 2-63 +/- 0-22 mul/cm2/30 min and was dependent on temperature and inhibited by 2,4-dinitrophenol, suggesting that fluid reabsorption is an energy-dependent process. About 50% of the fluid reabsorption was dependent on intraluminal sodium ions. This Na+-dependent component was inhibited by addition of amiloride to the intraluminal fluid and ouabain to the peritubular fluid.


Differing requirements for capacitation in vitro of mouse spermatozoa from two strains. Concentrated suspensions of epididymal spermatozoa obtained from two strains of mice, TO and C57BL/10, were preincubated for 20 min, 1 h or 2 h before dilution and addition of (C57BL/10 X CBA)F1 eggs. While all 3 groups of TO spermatozoa demonstrated high fertility (greater than 90% of eggs subsequently cleaved), C57BL/10 spermatozoa preincubated for 20 min and 1 h gave significantly reduced fertilization rates compared with those in the 2 h group. Furthermore, the penetration rate of the C57BL/10 spermatozoa preincubated for 20 min was significantly slower than that for similarly treated TO spermatozoa, as demonstrated by a delay in the first cleavage. A long preincubation of C57BL/10 spermatozoa in a diluted rather than a concentrated suspension did not improve fertility, suggesting that optimal capacitation may be sperm concentration-dependent in some, if not all, strains of mice.


Fertilization in vitro and development to term of unfertilized mouse oocytes previously stored at --196 degrees C. Unfertilized mouse oocytes were frozen and stored at --196 degrees C. Immediately after thawing 331 out of 463 MF1 oocytes (71-5%) and 271 out of 410 F1 (C57BL X CBA) hybrid oocytes (66-1%) were morphologically normal. No significant difference was found between the survival of oocytes frozen and thawed with (70%) or without (66%) the surrounding cumulus cells. Fertilization in vitro of frozen-thawed oocytes was significantly lower than that of freshly collected control oocytes. The overall fertilization rate in vitro for MF1 oocytes was lower than with F1 (C57BL X CBA) hybrid oocytes. The presence or absence of cumulus cells during fertilization in vitro did not affect the fertilization rate. Live 14-day fetuses were obtained after transfer of frozen-thawed unfertilized oocytes directly to the oviducts of females mated with fertile males. However, much higher rates of survival (up to 45%) to 14-day fetuses and live-born were found after the fertilization of frozen-thawed oocytes in vitro and subsequent transfer at the 2-cell or blastocyst stage to pseudopregnant recipients.


A study of abortion in countries where abortions are legally restricted. In countries where induced abortion is permitted, national family planning programs are able to combine pre- and postconceptive fertility control methods to maximize success in achieving personally desired fertility levels and nationally desired growth levels. The proscription against induced abortion tends to produce criminal abortions and consequent morbidity and mortality which, in some countries, are often recognized as a national health problem. The International Fertility Research Program has undertaken this study of incomplete, inevitable, threatened and septic abortion cases, using a standard data collection instrument, to facilitate comparisons across institutions and countries. The data gather since 1971 in nine Asian, African and Middle Eastern hospitals includes 7,331 cases. Policies of the participating institutions with respect to what constitutes a therapeutic abortion affected the proportions of spontaneous abortions and of abortions induced outside the hospital and inside the hospital. Women treated for induced abortion tended to be of higher parity and more likely to have attained their desired family size than patients treated for spontaneous abortions. Morbidity rates were quite low for patients treated in centers where vacuum aspiration was mainly used, particularly in contrast to the morbidity rates for patients treated in centers where dilatation and curettage was used exclusively. High mortality rates in patients admitted with sepsis confirm the need not only for improvement of clinical procedures but also for reconsideration of the legal issues since many patients admitted with sepsis can be assumed to have had abortions induced.


Granulation tissue in the umbilical cord. The development of granulation tissue in the umbilical cord is described here for the first time. Nothing is known about the conditions necessary to produce such tissue.


A comparative study of spring-loaded clips and electrocoagulation for female sterilization. The surgical, immediately postoperative and delayed postoperative complications and complaints associated with spring-loaded clips and electrocoagulation as techniques of tubal sterilization at laparoscopy were evaluated in a comparative study. Each of the two techniques was randomly assigned to 150 subjects. All sterilizations were performed as outpatient procedures. Subjects were followed-up during the first six weeks and again at about six months after sterilization. Rates of complications (surgical and early postoperative) were similar for the two procedures. None of the subjects required subsequent hospitalization. Technical difficulties at surgery were more frequent with the spring-loaded clip technique, principally as a result of mechnical problems with the prototype laparoscope and clip applicator. Postoperative pelvic and abdominal pain were reported by a significantly higher proportion of the patients when the spring-loaded clip was used (spring-loaded clips, 43.6%; electrocoagulation, 31.5%). At the six-month follow-up examination, rates of abnormal pelvic findings and changes in menstrual cycle formation were similar for the two techniques of tubal occlusion. There was one procedure failure among the electrocoagulation patients and none among the spring-loaded clip patients.


Normal and abnormal labor progress: I. A quantitative assessment and survey of the literature. Quantitative labor data have been reported piecemeal in the literature; there is no previous unified report of the frequencies of each of the dysfunctional labor patterns (DLPs). In order to describe the labor process more clearly a labor diagnostic computer program was used to prospectively study an unselected series of 3,682 nearly consecutive labors from one institution. Cervicometric data for nulliparous and multiparous labor were very similar to the results of others. The absolute frequency with which each DLP was found to occur is compared with results in the literature. Protracted active phase dilatation was the most frequently occurring DLP and prolonged deceleration phase the least frequently occurring one. The relative frequencies of the DLPs, defined as the percentage of all DLPs that occurred, remained reasonably constant, regardless of parity or the absolute frequencies of the DLPs in a group of patients.


Arthrogryposis multiplex congenita in an abdominal pregnancy. A case of arthrogryposis multiplex congenita occurred in a 19-week fetus from a primary abdominal pregnancy. The unusual feature is the early synarthrosis, possibly caused by multiple factors. This case supports the concepts of multiple etiologic factors of arthrogryposis multiplex congenita.


Comparative contraceptive experience with three-month and six-month medroxyprogesterone acetate regimens. Three-month (150 mg) and six-month (450 mg) contraceptive regimens of medroxyprogesterone acetate (DMPA) as an intramuscular depot injection are compared in this paper. A total of 19,875 women participated in the study, accounting for 220,530 woman-months of use. A Pearl index of 0.1069 for the three-month regimen was significantly lower than for the six-month group, where the index was 0.4943 (p less than 0.01). Side effects were limited insofar as personal reasons and loss to follow-up were the most important single category for discontinuation of this contraceptive method. No thrombotic incidents occurred. It is concluded that both contraceptive regimens of DMPA appear to be acceptable with regard to use-effectiveness, patient acceptance and prevalence of side effects.


Human tubal fluid collection via vagina and its quantitative variations during the menstrual cycle. The culdoscope was used for easy approach to the fallopian tube, which was delivered into the vagina, and a Foley catheter (No. 8 French) was introduced through its fimbrial end for collection of human tubal secretion. It was left from one to eight days. The technique was successful in 54 cases out of 60, but we succeeded in collecting enough fluid in 44 cases only. The volume of human tubal fluid was studied in relation to the phase of the cycle. A peak of fluid volume was found to occur at the midcycle.


A new look at an old technique: sterilization by infundibulectomy. Removal of the fimbriated portion of the fallopian tube is, theoretically, quite an effective method of sterilization that has received scant attention in the recent medical literature. In this study 310 cases of infundibulectomy via laparotomy performed at the Castle Street Hospital for Women in Colombo, Sri Lanka, were analyzed. Most of the patients (88.4%) were sterilized within 10 days of the vaginal term delivery whereas the remainder were sterilized in the immediate postabortion period. General anesthetic was used in 93.9% of the procedures. Difficulties at surgery which prevented infundibulectomy were encountered in three cases (1.1%). Infection and other incision problems were the primary complications. Incision infection was noted prior to discharge in four postpartum cases (1.5%) and in no postabortion cases. At the time of the first follow-up visit, seven to 21 days after sterilization, this complication was noted in eight postpartum women (3.1%) and in one woman (2.8%) who had had an abortion. No pregnancies have been reported among the 169 patients who have already been seen at the six-month follow-up visit. The results of this study indicate that infundibulectomy is a safe and effective method of tubal occlusion for postpartum patients.


Evaluation of the model 78100A adult telemetry unit for use in fetal heart rate monitoring. A commercially available adult telemetry unit was adapted for use in fetal heart rate monitoring. Advantages included permitting the mother to ambulate during labor, monitoring the fetus while the mother was in transit from the labor to the delivery area and reducing electrical noise levels. Patient as well as physician acceptance has been uniformly excellent. Patients who normally would not have accepted monitoring acceded to the use of the telemetry system when informed that they could move about while in labor. The equipment is easy to adapt, widely available, relatively inexpensive and simple to use.


Estimation of fetal or neonatal weight from the biperietal diameter. This paper contains a table of predicted fetal or neonatal weight on the basis of the biparietal diameter. The tabulated values are derived under the assumption that the relationship between biparietal diameter and weight is nonlinear and that weight is best predicted by means of a third degree least square polynominal spline. We believe that our study overcomes the shortcomings inherent in a linear prediction formula, commonly employed in the literature.


Six-year continuation rates for CU-T-200 users. The long-term (six years) contraceptive effectiveness of the Cu-T-200 is evaluated based on 833 first insertions performed by physicians and nurse-midwives. IUD event rates (pregnancy, expulsion, pain/bleeding removal or removal for medical reasons) did not increase with increasing duration of use. The results of the study indicate that the Cu-T-200 is a safe and effective contraceptive for at least six years after insertion.


Synthetic models of DNA complexes with antimalarial compounds. 2. The problem of guanine specificity in chloroquine binding. Stacking interactions between the aminoquinoline ring of the antimalarial chloroquine and the purine bases have been studied by preparing and examining models in which the quinoline is linked to the base by a trimethylene chain. The degree of stacking of the models which reflects the strength of the interaction was quantitatively determined in water at different temperatures by hypochromism measurement in the uv. Adenine and guanine exhibit equal affinity for the quinoline nucleus as reflected by very close hypochromism values observed for the two models at all temperatures studied.


Nucleosides. 102. Synthesis of some 3'-deoxy-3'-substituted arabinofuranosylpyrimidine nucleosides. The synthesis of some 3'-deoxy-3'-substituted arabinofuranosylcytosine (4a-d) and uracil (7a-d, 8a-d, X =Br, I, N3, SCN) nucleosides was accomplished by treatment of the requisite 2',3'-anhydrolyxofuranosylpyrimidine nucleoside (5,6a,b) with the appropriate ammonium salt in refluxing ethanol. Cleavage of the oxirane ring provided the desired 3'-deoxy-3'-substituted pyrimidine nucleosides (4a-d, 7a-d, and 8a-d). In vitro screening of compounds 4a-d, and 7a-d, with L5178Y cells in culture showed no significant inhibitory properties.


Synthesis and some pharmacological properties of [4-threonine, 7-glycine]oxytocin, [1-(L-2-hydroxy-3-mercaptopropanoic acid), 4-threonine, 7-glycine]oxytocin (hydroxy[Thr4, Gly7]oxytocin), and [7-Glycine]oxytocin, peptides with high oxytocic-antidiuretic selectivity. [4-Threonine, 7-glycine]oxytocin and [1-(L-2-hydroxy-3-mercaptopropanoic acid), 4-threonine, 7-glycine]oxytocin (hydroxy[Thr4, Gly7]oxytocin) were synthesized by a combination of solid-phase and classical methods of peptide synthesis. A protected octapeptide was synthesized by the solid-phase method and following ammonolysis and purification 1 + 8 couplings in solution were employed to furnish the required key nonapeptide and acyl octapeptide intermediates, respectively. [7-Glycine]oxytocin was prepared from a sample of the protected nonapeptide intermediate used in the original synthesis of this peptide. [7-Glycine]oxytocin has an oxytocic potency (O) of 93 +/- 4 units/mg and an antidiuretic potency (A) of 0.0056 +/- 0.0003 units/mg. It has an O/A ratio of 16 000. [4-Threonine, 7-glycine]oxytocin has an oxytocic potency of 166 +/- 4 units/mg and an antidiuretic potency of 0.002 +/- 0.0004 units/mg. Its O/A ratio is 83 000. Threonine substitution has thus brought about a substantial enhancement in oxytocic activity and a fivefold enhancement in O/A selectivity. Hydroxy [Thr4, Gly7]oxytocin has an oxytocic potency of 218 +/- 8 units/mg and antidiuretic potency of 0.0040 +/- 0.0005 units/mg. Its O/A ratio is thus 54 500. All three 7-glycine-substituted analogues exhibit a marked sensitivity to Mg2+ on the rat uterus assay ststem and in the presence of 0.5 mM Mg2+ had oxytocic potencies in the range of 900-1000 units/mg. Should these peptides exhibit enhanced oxytocic selectivity in humans, they might offer a greater margin of safety than oxytocin in those clinical stiuations in which the latter is currently employed.