Dynamic loads experienced in correction of idiopathic scoliosis using two types of Harrington rods. This paper reports the results of a series of tests conducted to evaluate the dynamic loads exerted by the Harrington rod on the vertebral bones during the correction of idiopathic scoliosis. Two types of Harrington rods were tested: the standard stepped rod and a modified threaded rod. The latter had a threaded end replacing the standard stepped end. The tests were conducted on linear and nonlinear springs, the mechanical characteristics of which are similar to those previously obtained from measurements performed on human spines. The results of the tests are reported and the two rod designs are evaluated accordingly. The modified threaded rod shows definite mechanical advantages over the stepped rod; however, the design is still open for modifications to overcome certain functional difficulties. (The Custom Product Services of Zimmer Co. offers a child spinal threaded rod designed by Dr. Kenton Leatherman.)


Chronic venous hypertension in the tail of the Wistar rat. Venous hypertension in the extremities has been associated with new bone formation and with degenerative joint disease. The relationship between increased intraosseous pressure and bone remodeling was investigated in the vertebrae of the tail of the Wistar rat. In 5 of 15 animals, prolonged venous hypertension resulted in osteoblastic activity with new bone formation. The vertebral changes observed are likened to those seen in some spinal degenerative diseases.


Ultrasound aspiration biopsy transducer amniocentesis. Amniocentesis through an ultrasound aspiration biopsy transducer was performed 156 times. The technique is described and our results are presented. By closely monitoring the fetus and the needle entry into the amniotic cavity, we have avoided serious complications. The importance of adequate genetic counselling for the procedure is stressed, as most cases fall into the second trimester group, and the procedure is indicated in order to try to prevent inheritable disorders. The importance of continual monitoring of the fetus before, during and after the procedure is pointed out, and recommendations are made to avoid difficulties and complications in amniocentesis.


The use of human chorionic gonadotropin in recurrent abortion. Important unresolved problems associated with recurrent abortion are aetiology, prognosis and management. This communication describes hormonal monitoring in pregnancy of groups of patients treated with human chorionic gonadotropin (HCG). The outcome is compared with that in an untreated normal group and an untreated group with recurrent abortions.


A radiologic survey of various configurations of the lumbar spine. This paper reports an investigation to determine whether or not human spine configurations can be categorized into types by which one could predict the possibility of disablement at one specific level more than another. Configurations of the lumbar spine, the shape of the lower two lumbar discs, the anterior and posterior heights of discs, the sizes of the transverse processes of L4-5, the presence or absence of rudimentery ribs, and the presence of transitional vertebrae were studied in roentgenograms of 554 subjects. They concluded that the probable criteria for development of L4-5 degeneration were 1) high intercrestal line passing through the upper half of L4, 2) long transverse process on L5, 3) rudimentary rib, and 4) transitional vertebra. Criteria for development of L5-S1 degeneration were 1) intercrestal line passing through the body of L5, 2) short transverse process on L5, 3) no rudimentary rib, 4) no transitional vertebrae. A high intercrestal line and long transverse process probably act as antitorsional devices protecting the L5-S1 disc; hence the likelihood of degeneration at L4-5 is increased.


The accuracy of maternal observation of fetal movements. The accuracy of maternal observation of fetal movements was assessed in 20 patients during the last trimester of pregnancy. The effect of factors such as smoking, obesity, education and gestational age were correlated with maternal observations to establish the accuracy of the latter.


Oral and intravaginal prostaglandin E2 for cervical ripening and induction of labour. The effect of prostaglandin E2 (PGE2) in 'ripening' the cervix was studied in 33 patients who required surgical induction of labour. Patients included primigravidas and parous subjects between 36 and 42 weeks of gestation. Sixteen patients received a total oral dose of 5 mg PGE2 and 17 received 4 - 6 mg PGE2 intravaginally in the form of a gel. There was significant improvement in 'ripeness' of the cervix in all groups, the intravaginal route giving slightly better results than the oral route. Ten patients remained unsuitable for induction because of inadequate dilatation of the cervix or a high fetal head. Four patients on oral therapy developed late decelerations of the fetal heart and 3 of these were delivered by immediate caesarean section. The implications of this and the reasons for the inability to perform inductions after 'ripening' are discussed.


Triplet pregnancy. A 10-year review of cases at Baragwanath Hospital. A series of 61 triplet pregnancies delivered in the Baragwanath Hospital for the 10 years 1967 - 1976 is analysed, the incidence being 1 : 2 789 deliveries. The average maternal age was 29,6 years, and average parity 3,7; 60% had had adequate antenatal care, a figure significantly higher than that for the local normal pregnant population. The vast majority of the patients had vaginal deliveries, although the proportion of manipulative procedures was high. The duration of labour was strikingly short in most instances. The fetal outcome was impressively good, although somewhat better with the second triplet than with the other two. This indicates that, in spite of the recent tendency towards liberal use of caesarean sections in these patients, a careful and appropriate vaginal approach has its merits.


Pelvic dimensions and the outcome of trial labour in Shona and Zulu primigravidas. Pelvic contraction is very prevalent in Africa while radiological facilities to assess pelvic size and shape are seldom available. A trial of labour using simple guidelines on a cervicograph can enable the midwife to detect dysfunctional labour and can help medical staff to manage these problems. Radiological checks in 116 Black primigravid patients with dysfunctional labour demonstrated that an active trial of labour is accurate in determining which of these patients have marked disproportion requiring caesarean section, minimal disproportion requiring assisted delivery, or primary uterine inertia responding to oxytocic stimulation. The role of radiological pelvimetry in African obstetrics is discussed, and the radiological features of the Shona and Zulu pelves in this series are described.


The nephrotic syndrome in families.

The nephrotic syndrome in families. Six families, each with 2 siblings suffering from the nephrotic syndrome, are reported. The incidence, causes, clinical picture and management of the nephrotic syndrome occurring in families are discussed, as well as possible ways of preventing this syndrome.


Tuberculous pericarditis. A review of 100 cases. A retrospective survey of 100 Black patients with presumed tuberculous paricarditis showed that 82 presented with pericardial effusion while 18 had constrictive pericarditis. The mortality rate was 17%. Of the 82 patients with pericardial effusion, 15 developed 'constricting pericarditis' within 4 months; 12 required pericardiectomy. Sixteen patients died of cardiac tamponade; the effusion had been confirmed by a radio-isotope heart pool scan but had not been aspirated. This emphasizes the need for early and repeated pericardial aspiration. The fate of 38 rural patients with pericardial effusion was not known. Of the 18 patients with constrictive pericarditis, 7 underwent pericardiectomy, while 3 refused operation.


Radiological features of normal and abnormal pulmonary blood flow. A short review is given of the anatomy of the pulmonary arterial system and of the bronchial arterial system. The normal vascular pattern of the lung as well as the altered vascular pattern under a number of abnormal circumstances is described.


Psychiatric aspects of shoplifting.

Psychiatric aspects of shoplifting. Clinical evidence of depression present for some months before an episode of shoplifting without criminal intent was found in all 17 patients interviewed after the offence. The person at risk would appear to be a depressed middle-aged woman with a passive-dependent personality, married to an ineffectual rejecting husband who is unable to meet her dependency in times of crisis. Recognition of her depression and appropriate intervention are essential if a criminal deed is to be avoided.


Paroxysmal cold haemoglobinuria. A case report. The clinical and biochemical findings in a 35-year-old Black man with paroxysmal cold haemoglobinuria are presented. Particular attention is drawn to the possible triggers of the haemolytic process, and the treatment is briefly reviewed.


A stable non-prostaglandin inhibitor of platelet aggregation in human aorta intima extracts. An inhibitor of platelet aggregation induced by adenosine diphosphate, collagen, adrenaline and thrombin is present in aorta intima extracts. The inhibitor is relatively stable and is not inactivated by prolonged incubation at 37 degrees C or 22 degrees C, but boiling for 15 seconds destroys it. It is not extracted by diethyl ether or chloroform, and is not affected by incubation with indomethacin or tranylcypromine. Platelet aggregation induced by arachidonic acid is not affected by this inhibitor. These results suggest that this inhibitor is not PGI2 (prostacyclin), a recently described potent anti-aggregatory agent generated by blood vessel microsomes.


Incidence of ovarian neoplasms at the Bloemfontein Academic Hospitals, 1972-1977. In the Orange Free State patients with gynaecological tumours are mainly referred to the National and Pelonomi Hospitals and the Department of Oncotherapy. During the 6 years 1972-1977 there were 1 895 admissions to the gynaecological wards of the National Hospital and 9 807 admissions to those of the Pelonomi Hospital. A total of 205 cases of primary ovarian neoplasia was seen, comprising 97 Whites and 108 Blacks. These cases were further divided into benign and malignant tumours and histologically classified into four main groups. Comparisons were made between cases seen in Bloemfontein and cases at other institutions.


Blood bupivacaine levels in standard and segmental epidural blockade in obstetrics. A statistically significant reduction in maternal blood bupivacaine levels could be achieved by using a segmental epidural blockade and lower concentrations of bupivacaine. Since bupivacaine has certain potential disadvantages for the mother and the fetus, its dosage should be kept as low as possible. Significantly lower blood levels without loss of analgesic quality are obtainable by using segmental epidural blockade and a lower concentration of bupivacaine.


The position of epidural catheters in obstetric regional anaesthesia. The fate of plastic catheters threaded into the epidural space was studied radiographically in a total of 125 catheters in 75 patients. The longer the segment of catheter, the less likely it is to reach the intended position, because it may curl up or become deflected. The most reliable technique for accurately placing an epidural catheter at any specific level is to enter the epidural space as close as possible to that level, so that the catheter does not need to be threaded for more than 2--3 cm.


Migration of a particulate radioactive tracer from the vagina to the peritoneal cavity and ovaries. In this report we describe a radionuclide procedure designed to evaluate the migration of a particulate radioactive tracer from the vagina to the peritoneal cavity and ovaries, as well as the determination of the patency of the pathways between these two extremes of the female reproductive system. 99mTc-labelled human albumin microspheres (99mTc-HAM) were deposited in the posterior fornices of 24 patients a day before they were to undergo different gynaecological operations. During this period sequential images were obtained and after the operation radioactivity levels in the removed organs and tissues were counted with a scintillation detector. In 14 out of 21 cases, the ovaries and fallopian tubes were counted separately from the uterus. Nine were positive (radioactivity levels were sufficiently high in the tubes and ovaries) and 5 were negative (no substantial radioactivity levels could be detected in either the tubes or the ovaries). The 5 negative results all occurred in patients with proved tubal damage as a result of previous infection. All the results were either true positive or true negative, providing evidence of migration, or obstruction, of 99mTc-HAM from the vagina through the uterus and tubes to the peritoneal cavity and ovaries.


A krypton-81m generator for organ ventilation and perfusion investigations. A sterile pyrogen-free generator for ultra-short half-life 81mKr has been developed. During initial loading, the binding efficiency of 81Rb is 90--99%. The count rate during perfusion is 3 x 10(5) counts per minute for a 1,9 GBq (50 mCi) 81Rb generator. The generator has been used for routine and special investigations of lung perfusion and ventilation and for myocardial perfusion during catheterization.


Folate metabolism and in vivo radiofolate binding in normal, folate-deficient and folate-saturated subjects. After ingestion of 14C-CH3H4Pte Glu by folate-deficient and folate-saturated subjects, and 14C-CH3H4PteGlu as well as 3H-PteGlu by a normal control subject, the dialysis-resistant (bound) plasma radiofolate fraction appeared increased in folate saturation and decreased in folate deficiency (compared with normal folate status). This suggests that absorbed radiofolate does not admix with the total folate pool before complexing with the plasma binder. As the bound plasma fractions appeared later than did the total biofolate peaks, in vivo plasma folate binding probably occurs independently of the intestinal folate absorption process. It also appears unrelated to postabsorption storage folate displacement, as this biofolate fraction is unbound. A bound radiofolate fraction persisting in plasma for 72 hours in spite of a normal food intake indicates a relatively inert binder complex.


[Appendicitis in the Black population].

[Appendicitis in the Black population]. In this retrospective study important aspects of appendicitis in 252 Blacks were studied and some interesting conclusions were drawn from clinical and operative data. Certain widely accepted impressions and beliefs are substantiated and others are refuted by the evidence found. In 38% of patients see, symptoms were present for more than 4 days before admission, but the clinical picture corresponded remarkably well with the textbook description. Operative findings revealed a diagnostic error rate of 18%, and the eventual mortality of 2% was confined to the 1st and 5th decades.


Knee ligament injuries.

Knee ligament injuries. Since acute surgical repair is vastly superior to any form of reconstructive procedure available, it is extremely important that acute ligamentous injuries of the knee do not go unrecognized. Chronic symptomatic instability after untreated major ligament injury marks "the beginning of the end' for the knee, and reconstruction is indicated. The classical stress tests for knee ligament disruption are generally reliable, and the interested doctor should have little difficulty in accurately diagnosing and classifying acute injuries or chronic instability. The technique of examination and classification of knee instability is described. The techniques of acute repair, as well as of selected reconstructive procedures, are described. Reconstruction for anteromedial subluxation is confined to advancement of the medial collateral ligament and posteromedial capsule as a single cuff, moving its tibial attachment distally and anteriorly. Fascia lata reconstruction is used for repair of anterolateral subluxation. Both these extra-articular anterior reconstructions can, in severe cases, be improved by the addition of a midline procedure, using the patellar tendon as an intra-articular graft. Transfer of the medial head of the gastrocnemius muscle is used for symptomatic posterior subluxation.


Myositis ossificans progressiva. A case report. The clinical and laboratory features of a case of myositis ossificans progressiva are described, and the recent literature concerning the pathogenesis and treatment of the condition is briefly reviewed.


Pituitary fossa volume in primary hypothyroidism. Pituitary enlargement can occur in primary hypothyroidism. Pituitary volume determination in 20 cases of primary hypothyroidism showed pituitary fossa enlargement in 25% of the patients, with close correlation to highest serum thyrotropin (TSH) levels. Normalization of TSH serum levels should prevent hypertrophy of the thyrotropic cells.


Pseudo-iniencephaly. A case report.

Pseudo-iniencephaly. A case report. A case of congenital webbing with other congenital abnormalities is presented. Initial examination of the features of the case made a diagnosis of iniencephaly seem likely. However, further examination of the radiographs and the physical abnormalities demonstrated too few of the typical features, and the term pseudo-iniencephaly has been used to describe the case. The various aetiological possibilities are discussed, but it is clear that further research into webbing and its concomitant abnormalities would be necessary to provide the answers to the questions posed by this case.


[Ophthalmomyiasis with subretinal tracks. A case report]. A 12-year-old White Boy presented with unilateral loss of vision and a severe vitreal inflammatory reaction after he had been struck in the eye by a flying object. After treatment with corticosteroids the vitreous cleared and the fundus could be seen. Indirect ophthalmoscopic examination and fluorescein angiography showed subretinal tracks consistent with the diagnosis of ophthalmomyiasis posterior.


Selective arterial embolization of the brain in an inoperable arteriovenous malformation in the thalamus. A case report. The embolization of an inoperable arteriovenous malformation of the brain using gelatin foam strips via the Seldinger technique is described. Subsequent operative ligation of the major feeding vessels was performed, with an excellent postoperative result.


Chlorambucil therapy in childhood nephrotic syndrome. Chlorambucil (Leukeran), a cytotoxic agent, was administered to 13 children with the nephrotic syndrome who had responded to steroid therapy, but frequently relapsed. In all patients corticosteroid therapy had become unsatisfactory. Eleven patients have so far remained in remission for an average follow-up period of 31 months since chlorambucil therapy. No side-effects of therapy were observed in this study, but several grave complications of high-dosage therapy have been reported in the recent literature. A dose of 0.2 mg/kg/d for 8 weeks should not be exceeded.


Smoking behaviour of White, Black, Coloured and Indian South Africans. Some statistical data on a major public health hazard. An analysis of the smoking habits of the population groups in the Republic of South Africa indicates an alarmingly high incidence of smoking, particularly among Coloureds. Significant numbers of men and women in all the population groups, especially Whites, are former smokers.


Bronchogenic carcinoma with coexisting active pulmonary tuberculosis in urban Blacks. There is a significant incidence of active pulmonary tuberculosis with coexisting lung cancer. It is likely that the cancer activates dormant tuberculosis. In a population group beset by a high incidence of tuberculosis, the heavy smoker who has attained his fifth decade seems particularly vulnerable to the combined diseases.


Postoperative Clostridium septicum dermatitis simulating toxic epidermal necrolysis. Widespread detachment of the epidermis as a result of Clostridium septicum infection after a laparotomy for intestinal obstruction is described. A clinicopathological picture, hitherto undescribed, is outlined.


Actinic chickenpox. Light-distributed varicella eruption. When areas of the skin which are normally covered become sunburnt just before chickenpox eruption, there occurs a marked intensification of the rash on the freshly burnt parts. This phenomenon is not widely known. Its history, published reports and our original observations on this 'actinic' chickenpox are presented, with comment on its pathogenesis.


The effect of long-term use of cimetidine on the ultrastructure of gastric parietal cells in man. The effect of long-term cimetidine therapy on the ultrastructure of human parietal cells was investigated in 2 subjects. It was found that after cimetidine therapy for 1 year: (i) the ultrastructural appearance of the parietal cells was normal, and (ii) the parietal cells responded normally to stimulation by pentagastrin. Evidence in favour of a membrane flow mechanism involved in acid secretion is presented.


The radiological features of primary pulmonary tuberculosis. A very brief review is given of the pathology of primary pulmonary tuberculosis. Numerous characteristic, but not pathognomonic, radiological appearances of primary pulmonary tuberculosis are briefly described and some of them are illustrated. The final diagnosis, however, depends on correlating the radiological picture with the clinical picture and special investigations.


Yersinia enterocolitica biotype 1 in South Africa. Two clinical isolates of Yersinia enterocolitica biotype 1, positive for indole and lecithinase production, xylose and salicin fermentation, and aesculin hydrolysis, are reported. One strain, serotype 0 6, was recovered from a healthy food handler, while the other, serotype 0 5, was associated with a diarrhoeal illness in a 1-year-old child. This is the first report of either of these serotypes from human material in South Africa.


Antibacterial activity of amniotic fluid. The antibacterial activity of amniotic fluid against Escherichia coli in the last month of pregnancy was reduced in an unselected sample of mothers delivering in Cape Town. Amniotic fluid zinc, required for normal antibacterial activity, was also reduced. These findings offer an explanation for the high incidence of amniotic fluid infection previously reported.


Creatine phosphokinase and lactate dehydrogenase levels after ultra long-distance running. An analysis of iso-enzyme profiles with special reference to indicators of myocardial damage. Blood samples obtained from 20 runners on completion or partial completion of a 160-km marathon were assayed for total serum creatine kinase (CK) and lactate dehydrogenase (LD), as well as for the respective iso-enzymes. Total CK was significantly elevated in all subjects, the mean value (2 243 U/l) constituting a 24-fold increase above the normal upper limit. In 65% of these cases, the cardiac-specific iso-enzyme of CK, MB, was present. The mean LD level (1 220 U/l) also exceeded the upper limit of normal significantly, 5 subjects presenting a 'flipped' LD pattern (LD1 greater than LD2). Three subjects exhibited the MB iso-enzyme in the presence of a flipped LD pattern. No electrocardiographic evidence of irreversible cardiac 'damage' could, however, be established after the race, nor any significant decrease in the Bruce protocol stress test rating. It is concluded that the MB iso-enzyme of CK, even in conjunction with a flipped LD pattern, may not represent unequivocal evidence of myocardial damage under all circumstances.


Absorption of iron polymaltose and ferrous sulphate in rats and humans. A comparative study. Free iron in the circulation in contrast to iron complexed with protein or carbohyrdate, is intensely toxic. The annual morbidity and mortality from accidental overdose with iron salts is significant and has directed attention to the evaluation of safer forms of therapy. Comparative studies between oral ferrous sulphate and iron polymaltose in rats established an LD100 of 350 mg/kg for the salt, whereas neither morbidity nor mortality could be produced in doses exceeding 1 000 mg/kg for the complex. Bio-availability of iron from salt and complex for haemoglobin synthesis was then compared both in rats and in man with a twin-isotope technique. In experimental animals and in the human studies, venesected individuals were used to reproduce the iron deficiency state where treatment would be indicated. It was concluded that bioavailability is comparable for therapeutic doses of ferrous sulphate and iron polymaltose in iron-deficient subjects. The marginally lower absorption of complex was offset by a greater degree of gastrointestinal tract tolerance; the wide margin of safety may be of importance in reducing the danger of accidental iron overdose.


Rehabilitation after mastectomy: the group process. Mastectomy is a frequently performed, emotionally stressful surgical procedure. Based on theories of loss and grief and crisis intervention, an in-hospital group program has been established to facilitate rehabilitation of patient and family. This paper discusses the alleviation of grief reactions and the fostering of growth-producing behavior through early postoperative participation in such groups. The function of the social worker as a member of an interdisciplinary team is examined, with particular focus on skills involved in promoting and enhancing the group process.


Social work practice and chronic pediatric illness. The role of social workers in a pediatric chronic illness setting is presented. The difference between acute and chronic illness is explored, with emphasis on the ramifications of these differences for social work practice. Early assessment of patients and families provides the social worker with a data base from which to select an appropriate intervention with families. Of primary importance is the amelioration of feelings of helplessness, dependency, and isolation. This may be accomplished by helping families anticipate problems, mobilizing resources to help, and encouraging families to share their experiences with other families. Because the medical system, particularly  in a teaching hospital, may not provide continuity of care for patients, the relationship of the social worker to patient and family, and resulting knowledge of the family, becomes an important resource in the provision of high-quality care.


Group psychotherapy on a children's urology service. This paper describes an ongoing program, in a large metropolitan hospital, of weekly group meetings for hospitalized children on the Babies Hospital Urology Service, led by a pediatric psychiatrist and a psychiatric social worker. The purpose of the program is to help children cope with the multitude of fears and anxieties that can arise in the course of hospitalization. Although not described in detail, corollary weekly group meetings are also held with parents of the children. The authors describe the format of their meetings with child patient groups, whose composition is, by its nature, a constantly changing one. Examples are excerpted from typical group sessions, indicating the kinds of problems that surfaced and how they were dealt with. Ways in which group interaction and support contributed to the positive results of such meetings are also shown. The authors suggest that their program can be utilized in a variety of hospital settings.


An interdisciplinary health care setting's experience with groups for parents of children having specific disabilities. This paper describes the planning, implementation, use, and evaluation of a group for parents of children with Williams elfin facies syndrome in an interdisciplinary health care setting. The group utilized a modified educational approach that resulted in significant gains reported by participants in learning about educational opportunities and rights of the handicapped, terminology and labeling of Williams syndrome, and meeting and sharing with other parents. The experience has implications applicable in interdisciplinary health care settings for use of groups as an aid in reducing the conflict that may result from the frequent combination of research and service to individuals with specific disabilities.


The integration of services of a medical clinic and a community mental health center in a rural area. This article describes the authors' use of open systems theory and exchange theory as a model for integrating the services to clients by the Community Medical Group (a private medical clinic) and the Mississippi River Human Services Center (a federally funded public community mental health center). As the directors of their two programs, the authors specifically patterned the integration of their services after the systems theory model of inputs, processing, and outputs. Expensive duplication of services was avoided, and the two programs worked together to develop needed programs to serve the emotionally troubled, the alcohol/drug abuser, and the developmentally disabled in their service area.


Providing health and social services to illegal alien families: a dilemma for community agencies. Proposals for dealing with illegeal migration from Mexico to the United States generally do not recognize it as an international social problem. The proposals also present contradictory solutions. Amnesty, a humanitarian policy, is being suggested as well as increased restrictions and punishments, a policing policy. However, in the absence of a comprehensive national policy, community social and health care programs must provide services to illegal aliens. This article attempts to document some of the issues that illegal immigration presents for community agencies.


Typologies in social work practice.

Typologies in social work practice. Two examples of diagnostic-intervention typologies are presented as derived from case record review. A multidimensional classification combines the origin, location, and identification (via family diagnosis) of children's "behavior problems" with treatment strategies for each of the six types. In the second example, a prescriptive typology of families with a newly diagnosed retarded child draws upon family and crisis theories to help define problem areas of family functioning. The typologies are suggested as tools but not stereotypes for clinical social work practice.


Small intestine cutaneous fistulas.

Small intestine cutaneous fistulas. A retrospective study of 174 patients with small intestine cutaneous fistulas was carried out. Cause, location of fistula, amount of output, presence of inflammation, intestinal obstruction, presence of malnutrition and anemia are associated wih an increased mortality. The results of various modes of treatment indicate that intestinal resection with primary anastomosis, carried out six weeks or later after the onset of the fistula, was associated with the lowest mortality and the highest success rate.


Circulatory effects of endotoxin on unanesthetized sheep and the response to dopamine. The cardiovascular effects of endotoxin in the unanesthetized chronically instrumented sheep were investigated. The observations were extended to include the response to intravenous infusions of dopamine to the same sheep at the height of endotoxin action. When the cardiovascular effects of endotoxin in the unanesthetized and anesthetized sheep were compared, there were distinct differences. Unanesthetized sheep tolerated considerably greater dosages of endotoxin. In anesthetized sheep, the compensatory stimulation of the sympathoadrenal system seems to have been blunted and all of the circulatory parameters deteriorate rapidly, ending in death within three hours. In the absence of anesthesia, there was clear evidence of a compensatory sympathoadrenal stimulation, as reflected by the return of most of the circulatory parameters to normal values, and furthermore, the sheep recovered from the effects of endotoxin. The exact mechanism by which anesthesia altered the response of the sheep to endotoxin was not clear. Depression of the baroreceptor and neurohumoral compensatory mechanisms was suggested. The present data indicated that dopamine was a useful agent in correcting the cardiovascular changes brought about by endotoxin.


Hormonal aspects of suction drainage after thyroidectomy. Suction drainage, after thyroidectomy, for a variety of conditions, varied between zero and 92.5 milliliters. The levels of thyroxine in this fluid were greater than those in the serum, at the same time being an average of 14.0 micrograms per 100 milliliters. The loss of thyroxine for 24 hours could represent up to 11.6 per cent of the total serum thyroxine pool. The serum thyroxine level, after initial fluctuation in either direction settled down, or up, to an average euthyroid level of 6.09 micrograms per 100 milliliters by the 21st day after operation. Possible factors influencing these changes have been considered and discussed. Such changes did not outweigh the advantages most surgeons found in drainage but could be eliminated if the ideal of no drainage could be attained. There was no evidence of exfoliated acinar cells in the drainage fluid.


Recurrent stenosis after carotid endarterectomy. Thirteen of 1,250 patients required a second operation for recurrent stenosis following carotid endarterectomy performed at the Cleveland Clinic between 1958 and 1978. Two other patients underwent reoperation because of recurrent stenosis following primary operations at other institutions. Thirteen of the 15 patients experienced neurologic symptoms caused by recurent stenosis, while two patients remained asymptomatic. Atherosclerosis was responsible for recurrent stenosis in 12 patients and appeared to be related to hypercholesterolemia. Three of the patients had myointimal fibroplasia. Eleven of the 16 reoperations for recurrent stenosis of the carotid artery consisted of carotid endarterectomy with vein patch angioplasty. Three patients had carotid endarterectomy with closure of the primary arteriotomy. One patient with occlusion of the internal carotid artery underwent endarterectomy of the external carotid artery because of amaurosis fugax, and a saphenous vein interposition graft was used to replace a previous Dacron graft in one patient with anastomotic stenosis. One patient had a stroke during reoperation manifest as multiple retinal emboli. Fourteen patients have remained asymptomatic from one to 70 months following reoperation. One patient with occlusion of the contralateral internal carotid artery has experienced persistent vertebrobasilar symptoms.


A clinical evaluation of cricothyroidotomy. Cricothyroidotomies were performed upon 147 patients at the New York University Medical Center and Booth Memorial Center from March 1976 through February 1978. Cricothyroidotomy was demonstrated to be a rapid and technically simple and precise procedure. The incidence of complications was 8.6 per cent. Catastrophic complications occurred in two patients who had severe laryngeal stenosis. Cricothyroidotomy was performed following prolonged endotracheal intubation in these two patients who had airway obstruction immediately following endotracheal extubation. In both patients, there was a glottic and subglottic component to the laryngeal stenosis suggesting that endotracheal intubation as well cricothyroidotomy played a critical part in the development of laryngeal stenosis. In view of these observations, we believe that cricothyroidotomy is useful, particularly in emergency situations and in patients with median sternotomy incisions but is contraindicated in patients having endotracheal intubation of more than seven days' duration or in patients having airway obstruction develop following removal of an endotracheal tube except as a temporary lifesaving procedure.


Objective improvement after aortofemoral bypass for exercise ischemia. The physiologic and functional improvement after aortofemoral bypass was quantitatively assessed by preoperative and postoperative noninvasive vascular testing in two groups of patients operated upon for claudication alone, those with significant occlusive disease of the lower extremity limited to the aortoiliac segments and those with combined disease of both the aortoiliac and superficial femoral arteries. While there is a statistically significant increase in segmental pressures and exercise times after aortofemoral bypass in the group with combined disease, these objective hemodynamic parameters are far from normal and are statistically significantly lower than values obtained in the group of patients with open superficial femoral arteries. Accordingly, we question the advisability of proximal arterial reconstruction in patients with combined hemodynamically significant aortoiliac and occlusive disease of the superficial femoral artery and claudication as the only indication for operation.


Effects of cooling and intraluminally administered antiseptics on surgically induced ischemia of the intestine in dogs. The efficacy of surface cooling and intraluminal antiseptic solutions for short term preservation of intestinal segments in preparation for free tissue transfer were investigated. Five segments of the small intestine and five segments of the colon were allocated to each group as follows: group 1, ischemia at 37 degrees C.; group 2, ischemia at 6 to 12 degrees C., and group 3, ischemia at 6 to 12 degrees C. plus povidone-iodine intraluminally. Histologic grading of segments allowed assessment of the efficacy of short term protection against ischemic changes. Surface cooling effectively prevented histologic evidence of ischemia. No additional benefit was observed using povidone-iodine intraluminally. Significant changes in tissue water content and evidence of bacterial invasion were not observed.


The effect of intermittent compression of the calf on the fibrinolytic responses in the blood during a surgical operation. The fibrinolytic responses in the blood during surgical operation have been studied in two groups of patients during intraoperative intermittent compression of the calf. Fibrinolytic activity did not differ significantly between the groups. The postoperative fibrinolytic shutdown was not prevented by intermittent compression of the calf. It is concluded that, whatever the mechanism by which venous thrombosis is prevented by intermittent compression of the calf, it is not by further stimulation of systemic fibrinolysis.


Arterial monitoring through the inferior epigastric artery during celiotomy. We have performed inferior epigastric artery cannulation for arterial pressure monitoring and blood sampling in ten patients with no associated complications. This site is easily accessible upon celiotomy, expendable and secure. For these reasons, we believe cannulation of the inferior epigastric artery is the preferred method of arterial monitoring in the patient undergoing celiotomy.


Osteomyelitis of the skull.

Osteomyelitis of the skull. This retrospective study includes 18 patients who underwent 28 admissions for treatment of osteomyelitis of the skull. Each admission was reviewed separately. Systemic symptoms were rare and signalled the presence of an associated collection of pus. Films of the skull, polytomography and bone scans were all useful in establishing the diagnosis, whereas white blood cell count, erythrocyte sedimentation rate and brain scans were of little value. Complete surgical debridement was found to be of significantly greater value than limited surgical debridement. The surgical results appeared to be improved when surgery was followed by long courses of antibiotics. Each patient who received complete surgical debridement followed by at least six weeks of antibiotic therapy was cured.


Intracranial germinomas: treatment and results. Eighty-nine patients with intracranial germinomas were treated from 1954 through 1975. Radiotherapy was given in 62 patients. The five-year survival rate was 61% and the ten-year survival rate was 55%. In unbiopsied patients the five-year survival rate was 66% and the ten-year survival rate was 59%, whereas in biopsied ones it was 56% and 47%, respectively. Prophylactic irradiation to the spinal axis in the presence of germinoma cells in the cerebrospinal fluid may not be justified.


Vermian hematoma in a four-year-old child. An unusual case of a vermian hematoma from the rupture of an angioma in a four-year-old child is presented. The lesion was treated successfully with complete recovery.


Interhemispheric subdural empyema with enlarged meningeal arteries. A successfully treated case of an interhemispheric subdural empyema is reported. In addition to the characteristic angiographic and computed tomographic findings, the present case was accompanied by enlarged middle meningeal and anterior falx arteries.


A comparative study of performance characteristics of cerebral aneurysm clips. The authors have developed a procedure to evaluate the performance of cerebral aneurysm clips as a function of intravascular pressure and aneurysm neck diameter. Numerous models of Mayfield, Scoville, Variangle, Heifetz and Yasargil clips were tested. The various clips demonstrated decreasing capabilities for secure occlusion of a vessel as  vascular diameters and intravascular pressure increased. These findings are in record with predictions based upon La Place's Principle and indicate that the size of an aneurysm must be considered in the choice of an appropriate aneurysm clip.


Brain abscess after transnasal intracranial penetration of a paint-brush. The case of a brain abscess caused by intracranial, transnasal penetration of a paint-brush is presented. The danger that such foreign bodies may remain unnoticed, especially in children, is stressed. Cure was achieved by total resection of the abscess capsule.


Traumatic cerebral swelling developing within 30 minutes after injury. Development of acute massive cerebral swelling within 30 minutes after closed head injury is documented by computed tomography. The swelling was rapidly resolved by steroid treatment. Detection and treatment of acute traumatic cerebral swelling are discussed briefly.


Intracerebral ciliated epithelial cyst.

Intracerebral ciliated epithelial cyst. The authors describe a case of hemispheric brain cyst of possible neuroectodermal origin, presenting as a frontotemporoparietal mass lesion. The etiologic aspects of intracranial neuroepithelial cysts are discussed.


Spontaneous spinal subdural haematoma during general anaesthesia. Spontaneous spinal subdural haematoma causing acute spinal cord compression is a well recognized condition and often responds well to early surgical intervention. In the elderly, the haematoma usually occurs as a result of minor trauma or atherosclerosis with hypertension. We present in this report the history of a patient who became paraplegic during a general anaesthetic for an operation for removal of a ureteral calculus. Rupture of a spinal vascular malformation was found to be responsible for the subdural haematoma, which remained undiagnosed until surgical exploration.


Peripheral enhancement in computerized cranial tomography: a non-specific finding. Peripheral enhancement of intracranial lesions on CT examination is still being considered by some radiologists as specific for an abscess or a cystic tumor. A review of the last 4,000 scans at this institution has demonstrated that it is neither specific nor, in many cases, of much help in the differential diagnosis of the lesions. Examples of the various types of lesions that can demonstrate peripheral enhancement are shown. It is suggested that many if not all types of pathology would demonstrate this effect if the cranial CT scans were done at a fortuitous time or sequentially. Some differential diagnostic suggestions are also made.


Rim enhancement in computed tomography with chronic epidural hematoma. Three cases of epidural hematoma with delayed clinical course are presented. In each patient, computed tomography (CT) initially failed to show typical biconvex, high density extra-axial lesion. The correct diagnosis was reached only after injection of contrast medium revealed enhancement of the border of the hematoma. Importance of contrast enhancement in selected patients with head injury is stress, and the mechanism of rim enhancement is discussed.


Venous malformation of the pineal region. A single and perhaps unique case of a venous malformation over the quadrigeminal plate causing acute obstructive hydrocephalus is reported. The lesion was well demonstrated by means of CAT scan but cerebral angiography failed to reveal the vascular nature of this lesion. Complete thrombosis of the lesion was achieved by surgical intervention and the resolution of the lesion was demonstrated by CAT scan. The patient remains asymptomatic and neurologically intact six months after the operation.


Primary sellar chondromas.

Primary sellar chondromas. Two cases of chondromas arising primarily from the sella turcica are reported. The eight cases reported in the literature are reviewed. The basic clinical and radiological findings of these tumors and the difficulties of diagnosis and treatment are discussed.


Anticoagulants and intracerebral hemorrhage from an unsuspected meningioma. A unique case of a patient with an undiagnosed convexity meningioma is presented. Hemorrhage into the tumor, following the administration of anticoagulant drugs for the treatment of thrombophlebitis, resulted in severe neurological defects and the eventual demise of the patient.


Combination chemotherapy with VM 26 and CCNU in primary malignant brain tumors. Twenty-seven patients with inoperable or recurrent primary malignant brain tumors after previous resection and/or radiotherapy, were treated with corticosteroids and a combination chemotherapy consisting of VM 26 and CCNU. There were 15 (55%) patients that responded, three with a complete and 12 with a partial response with a mean duration of response of 13.4 months. Toxicity was mainly hematological and of acceptable degree. Combination chemotherapy with VM 26 and CCNU is well tolerated and can be administered on an out-patient basis. In our experience it is better than single agent chemotherapy.


Experimentally induced cerebral aneurysms in rats: part II. An experimental condition that permits easy inducement of cerebral aneurysms in rats is reported. Previously, we demonstrated that saccular cerebral aneurysms were inducible in experimental animals and suggested that adult rats might be more preferable for inducing the lesion. Therefore, a longer-term study was performed intending to increase the incidence of cerebral aneurysms, using only adult rats. Adult rats were treated with ligation of one common carotid arter, deoxycorticosterone and salt hypertension, and beta-aminopropionitrile. Cerebral aneurysms developed in eleven of 30 rats which died 11-21 weeks after the start of the beta-aminopropionitrile feeding. All aneurysms were located on the anterior cerebral-anterior communicating arterial complex. Contributory mechanisms are discussed.


Primary aortoduodenal fistula: extra-anatomic vascular reconstruction not required for successful management. Eleven patients reported in the literature and three patients presented herein have survived treatment of primary aortoduodenal fistula by standard aortic reconstruction with prosthesis placement and duodenal repair. Follow-up of these patients documents that 93% (13 of 14) have had no graft-related complications. Standard aortic reconstruction appears to be justified in the treatment of primary aortoduodenal fistula.


The sepsis-glucose intolerance riddle: a hormonal explanation. Glucose intolerance has been commonly observed in sepsis and has been attributed to a multitude of endocrine and metabolic disorders. From 1977 to 1978, 19 patients were studied using intravenous glucose tolerance tests to evaluate this phenomenon; 15 patients presented with ongoing sepsis and four patients served as stress controls. Glucose intolerance was found to be a significant finding in less than 40% of the septic group. This state of intolerance was noted to be associated with a high mortality rate (60%), whereas glucose tolerance in sepsis was associated with a much improved mortality rate (10%). Hormone levels were correlated with glucose tolerance curves using the parameters of insulin, glucagon, growth hormone, cortisol, and epinephrine levels. Glucose intolerance and a high mortality rate were linked to sustained hyperglucagonemia, which was unresponsive to glucose challenge, and to marked suppression of growth hormone. This apparently represents a decompensated peripheral metabolic energy deficit, which results in the increased mortality rate.


The use of photoplethysmography in the assessment of venous insufficiency: a comparison to venous pressure measurements. In an attempt to develop a noninvasive test to assess objectively the magnitude of venous valvular dysfunction in pathologic states, photoplethysmography (PPG) was compared to venous pressure in the saphenous vein at the ankle. Simultaneous venous pressure and PPG recordings were taken before, during, and after exercise with subjects in the sitting position. In a total of 338 paired measurements in 24 normal, 25 postphlebitic, and 14 varicose limbs, PPG and venous pressure tracings appeared to be identical; data points had a correlation coefficient of great significance (r = 0.898). Postexercise recovery times clearly separated the normal from the postphlebitic limbs. Varicose limbs were assessed accurately regarding results of proposed surgery using an above-knee tourniquet. It appears that the PPG evaluation provides information comparable to venous pressure studies and does so more quickly and noninvasively. The test holds promise in measuring results of direct venous reconstructive surgery as well as in venectomy procedures.


Hemodynamic studies before and after extended bypass grafts to the tibial and personeal arteries. Thirty-ones limbs of 29 consecutive patients undergoing bypass grafts to the tibial or peroneal arteries were studied. Twenty-five limbs had ischemic rest pain with or without localized gangrene, and six had incapacitating claudication. The mean segmental pressure indices were upper thigh, 1.16 +/- 0.36; above knee, 0.71 +/- 0.30; below knee 0.51 +/- 0.23; and ankle, 0.28 +/- 0.21. Indices at the ankle were significantly lower (P less than 0.005) than those obtained from limbs that were candidates for simple femoropopliteal bypass. Three grafts failed immediately (initial patency rate of 90%). In the surviving grafts, ankle pressures rose from 39 +/- 26 to 145 +/- 29 mm Hg, and the ankle pressure index increased from 0.27 +/- 0.20 to 1.03 +/- 0.15 mm Hg. Consistent with these hemodynamic changes, all patients but one initially were relieved of their symptoms, and all ischemic lesions were treated successfully. Thirteen grafts failed subsequently (21 days to 34 months). Compared with preoperative values, ankle pressures after failure were either increased or unchanged in 75% of these limbs. Early occlusion could not be predicted on the basis of a low preoperative pressure index. During follow-up, impending graft failure was detected by a fall in ankle pressure in three patients and successfully prevented.


Results of subtotal parathyroidectomy for primary chief cell hyperplasia. Analysis of the long-term results of subtotal parathyroidectomy in patients with primary chief cell hyperplasia provides evidence that refutes the recent assertion that such treatment is often ineffective. With the use of rigid criteria, 55 patients with unequivocal chief cell hyperplasia were culled from 1,576 patients who had been operated on for primary hyperparathyroidism at the Mayo Clinic between July, 1959, and July, 1976. Follow-up information, including serum levels of calcium, was obtained for all patients up to at least July, 1977. Follow-up for surviving patients ranged from 1 year to 17 years (average, 3.9 years). Seven patients (13%) were not cured by subtotal parathyroidectomy and were left with persistent hyperparathyroidism after operation, presumably because a supernumerary gland was overlooked. However, not a single patient experienced recurrent hyperparathyroidism during the 213 patient-years of follow-up. In only three patients (5%) did permanent hypoparathyroidism develop following operation. These results reaffirm the efficacy of subtotal parathyroidectomy for primary chief cell hyperplasia and call into serious question the recent advocacy of total parathyroidectomy and autotransplantation of parathyroid tissue in these cases.


Primary aldosteronism: experience with thirty-eight patients. Thirty-eight hypertensive, hypokalemic patients underwent adrenalectomy for primary aldosteronism. Thirty-one patients were found to have an adenoma and seven patients "idiopathic" hyperplasia. The diagnosis was made by finding low plasma renin activity, which could not be stimulated, and unsuppressable elevated plasma or urine aldosterone. The distinction between adenoma and hyperplasia and the localization of an adenoma were accomplished by adrenal venography, adrenal vein blood analysis, and iodocholesterol scanning. Venography was accurate in 87%; adrenal vein blood analysis in 91%; and iodocholesterol scanning in 72%. Dexamethazone suppressed scanning heightened discrimination to 91%. The adenomas were equally distributed between the right and left adrenal gland, with one patient having bilateral adenomas. All but two patients underwent adrenalectomy from a posterior lumbar incision. Postoperative recovery was uncomplicated. Eighteen months after operation 77% of patients with an adenoma were normotensive.


Thoraco-omphalopagus conjoined twins: successful surgical separation. Male thoraco-omphalopagus conjoined twins were evaluated systematically with respect to visceral joining. Cardiac studies included electrocardiography, echocardiography, and a dynamic radioactive heart scan. No union was found. Liver union was demonstrated by scanning and angiographic studies. No communication between the gastrointestinal tracts was found, and no other major anomalies were discovered. When the twins were approximately 3 months of age, surgical separation was performed. A common pericardium, two separate hearts, and a union of the liver were found. Prosthetic sheeting was used to close the pericardium and the thoracic-abdominal defects in both. In one, primary skin closure was possible. In the other silicone rubber sheeting was used to close a large skin defect in the chest. Both have done well over a follow-up period of 14 months. One is larger than the other, but the growth rate of both has improved in the last 6 months.


Triple endoscopy: a neglected essential in head and neck cancer. Surgeons are sometimes embarrassed to discover a second unanticipated cancer while focusing attention on an already evident cancer in the head and neck area, the bronchus, or the esophagus. we began in October, 1976, to do direct laryngoscopy, esophagoscopy, and bronchoscopy on each of the 134 cases admitted to our unit with suspected head and neck cancer. In 10 of the 134 patients in whom triple endoscopy was done, no malignancy was found. Of 24 of 124 (20%) patients with head and neck cancer, 16 patients (13%) had synchronous carcinoma and eight patients (7%) had metachronous carcinoma in this 2-year period. The incidence can be expected to rise steadily with time and mandates "triple endoscopy" on all patients with a suspected cancer in the head and neck area, the bronchus, or the esophagus, as these structures form a closely related unstable field. The discovery of several patients with dysplastic mucosal changes, carcinoma in situ, or very early invasive cancer, not only of the head and neck but also of the esophagus and bronchus, presents new problems of management.


Teratogenic effects of nickel chloride on embryonic mice and its transfer to embryonic mice. Administration of nickel chloride to the pregnant mice on the seventh to eleventh day of their gestational period, resulted in significant embryotoxic effects in terms of an increased resorption rate, a decreased fetal weight, delay in skeletal ossification and high incidence of malformation. Among the cases of fetal malformation, the following malformations were observed to occur at a higher rate of incidence: acephalia, exencephaly, cerebral hernia, open eyelid, cleft palate, micromelia, ankylosis of the extremity, club foot and skeletal anomalies. Most skeletal anomalies were in the form of vertebral and/or rib fusions and were found mostly at thoracic and lumbar levels. The concentration of nickel retained in embryonic tissues was 800 times higher in the exposed compared to control groups and indicated that increased tissue levels of nickel chloride had a toxic influence on the developing embryo.


Embryotoxicity of transplacentally and intraamniotically administered 6-azauridine in mice. Embryotoxic effects were compared of intramuscularly (im) and intraamniotically (ia) administered 6-azauridine (Riboazauracil Spofa) in random-bred mice H-Velaz. Effects of single doses (0.25 mg, 2.5 mg, 25.0 mg and 250.0 mg for im and 0.0025 mg, 0.025 mg and 2.5 mg for ia administration) on days 11, 12, 13 and 14 were evaluated as a sum of dead fetuses and fetuses with cleft lip and/or palate, fetuses with limb deformities and fetuses with deformities constituting the syndrome of caudal regression (hypoplasia of the caudal part of the trunk, absent tail, short tail, curled tail). Considering the sensitivity peaks of the morphogenetic processes which were observed, the dose-response relationships, the transformation of the teratogenic to a lethal effect and critical period extension with increasing doses, it was found that the effects of ia and im administered 6-azauridine did not differ. It was concluded that ia administered 6-azauridine had direct effect on embryonic morphogenetic processes and that this, too, was the essential mechanism of embryotoxicity of im administered 6-azauridine. The value of the intraamniotic technique for establishing the direct embryotoxic effect is discussed.


An aberrant nucleus in the telencephalon following administration of ENU during neuroembryogenesis. Administration of ENU to rats during embryonic development caused the emergence of aberrant nuclei in the dorsal telencephalon. They were located in the corpus callosum, and were composed of pyramidal and stellate neurons. This suggested that the aberrant nuclei arose out of the neurons of cerebral cortex that had failed to migrate during embryogenesis. The aberrant nuclei were found predominantly in the animals receiving ENU on day 18 or earlier of gestation.


The fetotoxic potential of municipal drinking water in the mouse. Mice (CD-1 strain) were placed on diets containing either municipal drinking water (Durham, North Carolina) or water that had been distilled and passed through cartridges to reduce organics and remove inorganics. After a two-week acclimation period, animals were bred and pregnancy confirmed by the presence of a sperm plug. During the 8-month course of the study, approximately 500 pregnant mice were sacrificed on day 18 of gestation and their fetuses examined for visceral and skeletal anomalies. No significant water-related effects were found on any fetal parameter studied except for a 28.1% incidence of supernumerary ribs in the tap-water group as compared to 21.1% in the purified-water group. No differences were noted in the type or occurrence of anomalies between the two groups. A month to month variation was observed in a number of parameters. The degree of variation was similar for the treatment groups, suggesting that these changes might be random fluctuations.


Cadmium induced limb defects in mice: strain associated differences in sensitivity. Cadmium (CdSO4) was given ip on day 9 at 12 or 24 mumol/kg to pregnant CD-1 (non-inbred) mice. Fetuses showed malformations of the limbs, face, trunk, and tail. There was a statistically significant relationship between the dose of cadmium and the malformation rate. Cadmium (12 mumol/kg ip on day 9) was then given to mice of six inbred strains three of which (A/J, BALB/cJ, and C57BL6J) carry a gene cdm for resistance to cadmium-induced testicular damage, and three strains (AKR/J, CBA/J, and DBA/2J) which do not. Paradoxically, the three strains resistant to cadmium induced testicular damage were significantly more sensitive to its teratogenic effects than were the other three strains. In all inbred strains most malformations involved the limbs. All forelimb defects found in inbred or non-inbred cadmium treated mice were postaxial and indistinguishable from those produced by acetazolamide in mice. The remarkable similarity of the cadmium- and acetazolamide-induced forelimb malformations may be a reflection of the limited number of ways that a rodent forelimb can react to a teratogenic insult. The hindlimb defects were all preaxial.


Influence of drinking water -- tap versus purified -- on embryo and fetal development in mice. Pregnant CD-1 mice drank either chlorinated tap water obtained at NIEHS from the City of Durham, North Carolina municipal water supply or this same water passed in sequence through an organic removal cartridge and a demineralizer, followed by glass distillation. No significant overall differences in the reproductive status of pregnant mice were noted when the two groups were compared. Similarly, no significant overall influence on the incidence of malformed fetuses could be traced to the purity of drinking water. Month by month comparisons indicated that there were three statistically significant differences; all of which indicated improved performance for the mice that drank tap water. When the results for both groups were combined and a month by month comparison was made there was a significant difference in the pregnancy rate for February (68%) as compared with an overall pregnancy rate of 80% and a 79-93% spread for the other months, but the decrease was due to the low incidence of pregnancy in the group that drank the purified water.


Fetal and placental weight relationships in the albino rat near term. The relationship of fetal weight to placental weight was examined in 34 albino rats on day 22 of gestation. The influence of maternal weight, fetal position and the number of fetuses in the litter and each uterine horn were assessed also. There was no indication that rats with heavier placentas had heavier or lighter fetuses. However, within each litter, placental weight was weakly correlated (r = 0.297, p less than 0.01) with fetal weight. Maternal weight at mating, although positively related to the number of corpora lutea, was not related to mean fetal or placental weight. The number of fetuses in the litter was negatively related to placental weight but there was no apparent relation to fetal weight. Fetuses and placentas at the ovarian end of the horn were significantly lighter than those at the vaginal end. The strength of the fetal weight:placental weight correlation in the rat is compared to those in other species.


Fetal and placental responses to artificially induced hyperthermia in rats. Pregnant rats were utilized to study the effect of maternal hyperthermia on fetal development. Eight groups of six to eight rats were exposed to ambient temperatures of 43-44 degrees C at various stages of pregnancy. All rats were killed on day 20 of gestation. Edema, microencephaly and microphthalmia followed heat treatment on day 4, 6, or 8 and skeletal defects occurred on day 10 of gestation. Apparently heat stress of dams after day 14 of gestation had little or no effect on embryos. Most placentas from day 6-10 treatment groups were significantly heavier than control and exhibited extensive thickening and necrosis of decidua basalis. Our results suggest that the rat is a useful model for investigating maternal hyperthermia as a possible cause of human placentophathies and fetal retardation.


Cytogenetics of extragonadal tumors.

Cytogenetics of extragonadal tumors. Tissue from six human extragonadal teratomas was obtained for cytogenetic study. These included two gluteal lesions in infant females, and one each of thyroid, mediastinal, sacral and gastric teratomas in males. Tissue culture characteristics indicated tumor growth. All tumors, except the mediastinal lesion showed the presumed karyotype of its host, XX or XY. The mediastinal mass was tetraploid XXYY and contained an X chromatin body and double Y bodies. Our data support the concept that extragonadal teratomas in males and females arise mitotically from diploid cells and are more similar to identical twins. No heterosexual (XX) tumors were seen in males which would be expected in parthenogenetic tumors. The sex chromatin positive tumors seen in earlier studies may have resulted from polyploidy. Thus, male and female extragonadal teratomas have a different origin from the postmeiotic ovarian teratomas.


Equivalent ages in rat, mouse and chick embryos. Data for estimating equivalent ages of rat, mouse and chick embryos are presented, using several sources from the literature. When the time of development of various embryonic structures is matched for the three species, the differences in time for the stages are primarily due to delays in development of the preimplantation blastulas of the rat and mouse in comparison with the incubated chick egg. Development from the blastula stage to completion of major organogenesis proceeds at approximately the same rate for all three species.


Prenatal ethanol exposure in mice: teratogenic effects. C57BL/6J mice were fed a liquid diet in which 17, 25, or 30% of the calories were derived from ethanol from the fifth through the tenth day of gestation. Control mice were fed lab chow or pair-fed identical diets, except that sucrose substituted isocalorically for ethanol. At term the fetuses were removed and, following fixation, examined by microdissection. The incidence of fetal resorptions and congenital malformations increased in a dose-related manner. Anomalies included skeletal, neurological, urogenital, and cardiovascular systems. These data indicate that in mice, an alcohol diet which is adequate in vitamins and protein results in increased fetal wastage and birth defects.


Teratogenic effects of the plant hormone indole-3-acetic acid in mice and rats. These studies evaluated the teratogenic potential of indole-3-acetic acid (IAA), a naturally occurring plant hormone, in CF-1 mice and Sprague-Dawley rats. Mice were given 5, 50, 200, or 500 mg IAA/kg/day by gavage on days 7 through 15 of gestation. Rats were given 50, 200, or 500 mg IAA/kg/day by gavage on days 7 through 15 of gestation. IAA was teratogenic in mice and rats at 500 mg/kg/day; cleft palate was induced in both species at this dose level. In mice, other malformations including exencephaly, ablepharia, dilated cerebral ventricles, and crooked tail were also observed. Mice given 500 mg/kg of IAA gained less than control mice during gestation; no evidence of maternal toxicity was observed in rats. IAA did not cause fetal resorptions in either species and was not teratogenic at dose levels below 500 mg/kg.


Gap junctional vesicles in the neural tube of the splotch (Sp) mutant mouse. The lumbosacral region of the neural tube was studied by means of transmission electron microscopy in retrospectively confirmed normal (+/+; Sp/+) and abnormal (Sp/Sp) embryos of the splotch mutant mouse early on the ninth day of gestation when the caudal neural groove is normally in the process of closing to form the neural tube. In abnormal embryos, a consistent feature is the presence of gap junctional vesicles, particularly in the region of the neural groove which subsequently fails to close, whereas these structures are rarely observed in similar areas of normal embryos. The possible significance of gap junctional vesicles is discussed in terms of cellular adhesion during early neurogenesis.


The teratogenic activity of a thalidomide analogus EM12 in rats on a low-zinc diet. The relationship between the teratogenicity of EM12, 2-(2,6-dioxopiperiden-3'-yl) phthalimidine, a stable analogue of thalidomide, and zinc status in the maternal animal was investigated using pregnant rats on a low-zinc diet (1 ppm zinc, days 0--14 gestation) as the experimental model. Previous studies with this compound in rats fed a commercial diet at oral doses up to 250 mg/kg per day for three days and intravenous doses up to 10 mg/kg per day for three days failed to produce "typical" thalidomide malformations. However, when a dose of 150 mg/kg was given intraperitoneally to rats on a low-zinc diet, typical thalidomide malformations occurred with an incidence of 57.5%.


Changes in chemical composition of chick embryos treated with a beta-xyloside and a lathyrogen. Nine-day chick embryos were treated with 4-methylumbelliferyl beta-D-xyloside or beta-aminopropionitrile fumarate, and their gross chemical composition was examined one week later. Total DNA was 10--20% less in embryos treated with either drug than it was in control embryos. Xyloside-treated embryos showed marked increases in percent wet weight and in sodium/DNA and chloride/DNA ratios, and small decreases in protein/DNA, hydroxyproline/DNA and sulfate/DNA. None of these parameters was affected in embryos treated with beta-aminopropionitrile. Approximately 85% of the uronic acid of control embryos was present as chondroitin sulfate, with a degree of sulfation of 80% and charge density of 1.8; all of this chondroitin sulfate was covalently linked to peptide and had a number-average molecular weight of 29,300. In embryos treated with beta-xyloside, 90% of the uronic acid was present as chondroitin sulfate, with a degree of sulfation of 40% and charge density ranging from 1 to 2; 27% of this chondroitin sulfate, with an average molecular weight of 25,400, was peptide linked, while 73% was linked to 4-methylumbelliferone and had an average molecular weight of 22,900. The chemical differences between embryos treated with the xyloside and embryos treated with the lathyrogen reinforce the conclusion on morphological grounds that these are distinct syndromes involving different aspects of the extracellular matrix.


Plastic casts of embryonic respiratory and cardiovascular system: a technique. This report describes a technique for producing plastic casts of the cardiovascular and respiratory systems of the chick embryo at Stage 36 or older. For casts of the cardiovascular system, polymerization compound is injected in the right ventricle filling the heart, venous, and arterial system. A two stage injection produced more detailed casts of the pulmonary vasculature. For respiratory system casts, the compound is injected in the trachea filling the bronchi and air sacs. Casts are prepared by tissue corrosion in 10% potassium hydroxide. This technique is an alternative to serial section reconstruction in the study of developing cardiovascular and respiratory system.


Teratologic evaluation of synthetic delta 9-tetrahydrocannabinol in rabbits. Synthetic delta 9-tetrahydrocannabinol (THC) was dissolved in undiluted propylene glycol and administered in daily subcutaneous doses of 15.0, 30.0 or 60.0 mg/kg to pregnant New Zealand white rabbits on days 7--19 of gestation. Maternal food consumption and weight gain were markedly reduced at all dose levels. Embryotoxicity and embryocidal effects were observed in the form of reduced litter weight and number of viable fetuses, respectively, in offspring from pregnant mothers treated with THC. However, on the basis of extensive external, visceral and skeletal examination of all fetuses it may be concluded that THC is not teratogenic in the New Zealand white strain rabbit following subcutaneous administration of doses as high as 60.0 mg/kg/day during the critical period of organogenesis (days 7--19 of gestation). On the other hand, an oral dose of thalidomide (200.0 mg/kg/day), the positive control used in this study, was both embryocidal and teratogenic.


Teratogenic potential of inhaled carbon monoxide in mice and rabbits. Pregnant CF-1 mice and New Zealand rabbits were exposed to carbon monoxide at a concentration of 250 ppm for 7 or 24 hours daily during the period of major organogenesis, days 6 through 15 of gestation in mice and 6 through 18 of gestation in rabbits. Carboxyhemoglobin levels in the range of 10--15% were observed in both species (control animals had 0.7% or less). Carbon monoxide was not found to be teratogenic in either species. In mice, a significant increase in the incidence of some minor skeletal variants was observed. One litter in each of the carbon monoxide-exposed groups of mice was completely resorbed; none of the litters of control mice or of control or exposed rabbits were completely resorbed. The fetuses of mice exposed to carbon monoxide for seven hours daily were heavier than control fetuses, and those exposed for 24 hours daily were lighter than control fetuses. The reason for this result is not known.


Metabolism of the coagulation factors of the prothrombin complex in hypothyroidism in man. The metabolic rate of prothrombin, factors VII, IX and X, was studied in nine hypothyroid patients. Disappearance rates of the four vitamin-K-dependent factors, called the prothrombin complex, were measured after assumedly complete blocking of their synthesis with adequate doses of a coumarin congener (acenocoumarol). Reappearance rates were assessed by induction of synthesis with high doses of vitamin K1 (phytomenadion) when stable hypocoagulability had been achieved. Normal values for these rates were derived from earlier studies in our laboratory. In hypothyroid patients the rates of both disappearance and reappearance were significantly slower for all factors tested. Practical consequences of these observations are discussed. The initial level of factor-IX activity in all nine patients was substantially lower than in normal individuals. Therapy by thyroxine-substitution led to normal levels of factor-IX. This implies a divergency in the retardation of the breakdown and production rates in hypothyroidism. The reappearance rate was indeed found to be more retarded than the disappearance rate.


The frequency of bleeding and height of adolescent haemophiliacs. The relation between the height of adolescent haemophiliacs and their bleeding frequency has been studied. 45 haemophiliacs aged 10--19 years were divided into 3 groups: small, medium and tall, using a Height Standard Deviation Score. The average bleeding frequency per 100 days in the group of small haemophiliacs was 8.71 +/- SD 4.47, in the medium height group 10.18 +/- SD 6.71, while the tall individuals bled in average 15.97 +/- SD 3.15 every 100 days. There was no relationship between age and bleeding frequency.


Factor VIII inhibitor and bronchogenic carcinoma. An inhibitor to procoagulant factor VIII (FVIIIC) developed in a patient three years after palliative resection of a bronchogenic carcinoma. The inhibitor was not active against ristocetin cofactor but possibly had some activity against factor XI. It responded to immunosuppressive therapy. This is apparently the first reported association of carcinoma and factor VIII inhibitor.


Kinetic aspects of the interaction of blood clotting enzymes. VIII. The relation between clotting time and clotting velocity. It is shown that in a system where thrombin acts on fibrinogen, the clotting time can be used to assess coagulation velocity because clotting time and clotting velocity are inversely proportional.


Thrombin-like and factor X-activator components of Bothrops snake venoms. A comparative study on the coagulant activity of snake venoms was carried out in 26 Bothrops species, using specific clotting systems for the thrombin-like and the factor X-activator activities. With only two exceptions (B. erythromelas and B. castelnaudi) all venoms showed thrombin-like activity, since they were able to clot fibrinogen directly. The absence of thrombin-like action of B. erythromelas venom is due to a fibrinogenolytic effect. Five venoms (B. atrox asper, B. bilineatus bilineatus, B. cotiara, B. fonsecai and B. itapetiningae) were unable to produce a prothrombin activator when preincubated with serum, factor V, and phospholipid. None of the venoms seems to require factors VII, VIII, IX, XII and XIII for their complete coagulant action. Direct prothrombin activation was observed in most of the Bothrops venoms, alone or combined with thrombin-like and factor X-activator activities. An anticoagulant activity was exhibited by B. castelnaudi venom, probably due to an anti-Xa action. This study points out that the coagulant activity of snake venoms varies within the same genus and must be characterized for each species. Thus, in Bothrops venoms the thrombin-like and factor X-activator components are not always associated, the coagulant effect may be related only to one of the components.


Effect of sodium chloride on limulus amebocyte lysate. Inhibition of endotoxin activation of procoagulase. Concentrations of sodium chloride up to 3 M increase the time necessary for the clot formation from Limulus amebocyte lysate (LAL) induced with endotoxin. Sodium chloride at a concentration of 4 M prevents clot formation by either precipitation or denaturation of procoagulase. The time necessary for the activation of procoagulase by endotoxin is increased by a change in the sodium chloride concentration from 0.15 M to 0.588 M. No effect on the proteolytic phase or the polymerization phase of the clotting reaction is detected by the increase in sodium chloride concentration from 0.15 M to 0.588 M. The authors conclude that increased sodium chloride concentrations may aid the isolation of procoagulase.


Interactions between human plasma proteins and heparin-poly(methyl methacrylate) copolymer. A solid Heparin-PMMA copolymer has been synthetized by a radical polymerization of methyl methacrylate from oxidative reaction initiated by Ce4+ ions in the presence of heparin. Covalently linked heparin was 10% of copolymer weight. The antithrombin activity of the copolymer corresponded to 1% of grafted heparin. PMMA sequence of the copolymer played the leading role in fibrinogen, immunoglobulins, transferrin and albumin adsorption. These proteins adsorbed on the copolymer, showed different competitive desorption pattern in the presence of whole plasma: fibrinogen presented the highest degree of affinity for the copolymer. The heparin part of the copolymer was responsible for antithrombin III adsorption and for decrease of factor V activity. Active antithrombin III was eluted. An inactivation of factor V in plasma was observed using high concentrations of soluble heparin. This result suggested that copolymer heparin chains, even devoid of antithrombin activity were involved in this inactivation. With Heparin-PMMA copolymer, plasma clotting pro-enzymes behaved differently than on heparin-sepharose copolymer:disappearance of factor XI activity, decrease in prekallikrein activity and activation of factor IX were observed. PMMA sequences were responsible for factor IX activation.


Triglyceride lipase activity and human platelets. The activity of triglyceride lipases in human postheparin plasma is significantly higher in platelet rich than platelet poor plasma. This holds for total activity, lipoprotein lipase (LPL) activity, and hepatic triglyceride lipase (H-TGL) activity. Gel filtration of platelet rich postheparin plasma on Sepharose 2 B will separate platelets from triglyceride lipase activity. The very small triglyceride lipase activity of isolated platelets is inhibited by 1.0 M NaCl, slightly inhibited by specific antibody to hepatic lipase, and not influenced by specific antibody to lipoprotein lipase.


[Is anaemia of veal calves normochromic or hypochromic? (author's transl)]. The anaemia resulting from iron deficiency is described as hypochromic in the medical literature. In the veterinary literature, anaemia of veal calves is usually regraded as normochromic. In order to examine the correctness of this view, the present authors studied the Hb and haematocrit (Hc) levels of the blood of veal calves in a comparative feeding trial for sixteen weeks. Three groups of male Dutch-Friesian calves, each group consisting of approximately thirty animals, were fed a milk replacer which contained 5, 10 or 25 ppm of iron respectively. The calculated mean Hb-concentration in the erythrocytes of the animals given 5 and 10 ppm of iron dropped during the trial period to below levels occurring at the age of two weeks. In the group given 25 ppm of iron, the erythrocyte Hb showed a rapid increase from the age of ten weeks and continuing throughout the rest of the trial period. At the age of sixteen weeks, the groups showed significant differences (P less than 0.01) in their mean erythrocyte Hb-concentrations. In veal calves, fed milkreplacers having an iron content below 25 ppm of Fe, the anaemia therefore is hypochromic.


[Traumatic pericarditis, an old acquaintance in due form (author's transl)]. The clinical, radiographic and post-mortem studies in an 18-month-old heifer are reviewed. The complaint was that the animal had not been eating and drinking for as long as ten days. Clinical studies revealed obvious changes of the respiratory and circulatory systems: marked engorgement of the jugular veins, clapotement synchronous with the heart beat and bronchial respiration over the apical lobes. Clinical examination was followed by a differential diagnosis in which traumatic pericarditis, pleurisy and an intrathoracic abscess were mainly considered, and is was decided to carry out radiography. The X-rays showed a major lesion, within which a horizontal level was observed. In addition, a large foreign body was discernible. The animal died within a few days and the diagnosis of traumatic pericarditis was verified, though pleurisy was also found to be present. The ichorous splenitis revealed by the post-mortem studies was not observed on clinical examination. The difficulties involved in arriving at a correct differentiation between pericarditis, pleuristy and an abcess are discussed in retrospect.


An investigation of the pathology of mycoplasma mastitis in the cow. A field case of mastitis in cows, caused by Mycoplasma agalactiae var. bovis, formed the occasion to conduct an infection experiment. Five lactating heifers were infected in the udder at different times. The cows were slaughtered 2, 5, 7, 9 and 12 days p.i. and the pathological changes were studied. The investigation indicated that the pathological picture differed with time: in the acute stage, the inflammation was characterized by exudation of mostly eosinophils in the alveoli; later on, the mastitis was identified by an interstitial reaction with eosinophils and mononuclear cells, including plasma cells and lymphocytes; in the chronic stage, progressive fibroplasia around ductuli and alveoli, with hypertrophy of alveolar epithelium, was characteristic. The pathological findings are discussed.


Severe extrapyramidal syndrome in a dog caused by a haloperidol (Serenase) intoxication. The case history of a one-year-old male mongrel dog intoxicated with 120 mg haloperidol is described. The dog showed a coma with a severe extrapyramidal syndrome and was treated with orphenadrine. Symptoms, occurrence, and therapy of the extrapyrmidal syndrome are discussed. Emphasis is laid on the importance to differentiate this syndrome from epilepsy and other neurological disorders.


Induction of parturition in the sow with a prostaglandin analogue (I.C.I. 80996). Parturition was induced in 112 gilts and sows on day 111,, 112, and 113 of gestation by means of a single intramuscular injection of 175 mcg of a prostaglandin F2 alpha analogue (Cloprostenol, I.C.I 80996). No side effects were detected immediately after injection and the course of the induced parturition was normal. The interval between injection and parturition was approximately 28 hours. Induction of parturition on day 113 resulted in a significant shortening of this interval as compared with day 111, and 112. The average weights of the piglets at birth and at 5 weeks were within the normal range. The percentage of stillbirths and the loss of piglets up to weaning did not differ significantly between control and experimental groups. The practical applications of induction of parturition are discussed.


Nutritional and metabolic aspects of fatty liver disease in poultry. There are two metabolic disorders of major commercial importance in poultry that involve the occurrence of fatty deposits in the liver. Fatty Liver and Kidney Syndrome (FLKS) affects young birds and the main manifestations, lipid infiltrations into liver and many other organs, are apparently secondary effects of the primary lesion that lies in carbohydrate metabolism. Although several nutritional and environmental factors influence FLKS, the main factor is the vitamin, biotin. In the absence of an adequate supply of biotin, the hepatic activity of pyruvate carboxylase, a biotin-dependent enzyme, becomes so low that gluconeogenesis in the liver via pyruvate becomes negligible. When the bird is then subject to a mild stress and/or short term fasting, liver glycogen reserves become rapidly depleted and a progressive hypoglycaemia develops that ultimatley proves fatal. Supplementing diets with adequate amounts of biotin can prevent the syndrome. Fatty Liver Haemorrhagic Syndrome (FLHS) is brought about by an excessive accumulation of fat in the livers of adult hens which weakens the cellular structure of the liver and allows fatal haemorrhaging to occur. The aetiology of the syndrome is not clear, but a major factor is an excessive intake of dietary energy. However, the involvement of hormonal and toxicological factors, as well as other nutritional factors, is also possible.


Haemadsorption inhibition test for the identification of Mycoplasma gallisepticum and Mycoplasma synoviae. Colonies of the avian mycoplasma strains Mycoplasma gallisepticum S6 and Mycoplasma synoviae WVU 1853 and two Mycoplasma synoviae isolates from this laboratory were shown to be haemadsorption positive for chicken erythrocytes. Three Mycoplasma synoviae isolates from this laboratory proved to be haemadsorption and haemagglutination negative. The haemadsorption of the mycoplasma colonies mentioned above was inhibited with specific antisera of either high or low titre. No cross-inhibition was observed. It is suggested that this test could be used for a quick tentative identification of the two avian mycoplasmas on primary solid-medium cultures.


Common diseases of pet animals in West Africa. A brief review of the major disease of exotic pet animals in West Africa is presented, based on experience, mainly in Nigeria; with pet animals imported from Europe. The conditions mentioned are: ticks, and tickborne diseases, rabies, distemper, feline panleukopenia, trypanosomiasis, hookworm and tumbu-fly infections. The control measures before departure are emphasized.


The structure of A segments from glycerinated skeletal muscle. The A band of skeletal muscle consists of an array of thick myosin-containing filaments along with non-myosin proteins such as C protein and M line protein. In order to study the arrangement of the myosin and non-myosin components, A segments which are aggregations of thick filaments held together at the M line were prepared from glycerinated chicken pectoral and rabbit psoas muscles and examined by electron microscopy. Details of the preparative technique and comparison of the morphologies of A segments and I segments are provided. The A segments from chicken pectoral muscle exhibited 11 to 12 stripes in each half lateral to the bare zone. Several less distinct bands as well as subdivisions of the individual stripes were also observed. The periodicity of the major stripes in the A segments was 424 +/- 10 A. The A segments prepared from rabbit psoas muscle had a periodicity of 432 +/- 13 A, but in contrast with chicken A segments, fewer rabbit A segments showed this periodicity. We conclude that A segments can be separated from glycerinated chicken and rabbit skeletal muscles and compare our results with those of others who prepared A segments from frog and rabbit skeletal muscles in the absence of glycerol.


Aggregates of particles on the plasmalemma of striated muscle from a spider. Aggregates of large intramembranous particles are described in the surface membrane of muscle fibers of a spider. The particles are continuous with extensions into the extracellular space, forming large complexes. No intramembranous particles are visible at sites of Z line attachment to the plasma membrane.


Fine structure of muscle and other components of the trunk of Sagitta setosa (Chaetognath). The histology of the Chaetognath's trunk is largely based upon works of Hertwig (1880) and Burfield (1927) and is revised here essentially on ultrastructural basis, in a study on Sagitta setosa. The trunk is composed of a thick multilayered epidermis, without cuticle, and contains an abundant nervous system. It is separated from the underlying general musculature by a "basement membrane" which is not crossed by nerves fibres in the region of the ventral ganglion. We have been mainly interested in the muscular tissue. It has no close contact with the body cavity but is surrounded by a thin monolayer epithelium. The general musculature is composed of two types of muscles. The first one, forming the primary musculature, is divided by mesenteries and lateral fields into four quadrants. It contains groups of fibres (C then A) alternating with other groups of fibres (B). The second one, constituting the secondary musculature, is divided into four bands. Both types of fibres are readily identifiable by their myofibrils. The fibres of primary musculature, in close contact with their membrane level, have no basement lamina except at the myoepidermic junctions.


Organ culture of adult amphibian heart: a fine structural analysis. Pieces of hearts from adult newts were cultured up to 2 months. Within 7 days of culture, approximately 37% of the cardiac explants were attached to the substrate and more than 33% of the attached explants and approximately 15% of the unattached explants established pulsation rates ranging from 3 to 67 beats/min. The control and cultured explants were processed at weekly intervals for electron microscopy. The diameter of the control cardiac muscle cells ranged approximately 3-5 micron. The cell surface was provided with microvilli. The intercellular spaces ranged approximately 150-500 A. The intercalated discs lacked the step-like courses observed in the mammalian cardiac muscle. Sarcoplasmic reticulum was scanty. Desmosomal-dense materials were frequently continuous with the Z-bands of both control and cultured cardiac muscle cells. The transverse tubular system and gap junction were absent in newt ventricles. The functional implications of these characterisitics are discussed. At the end of 1 week of culture, the surfaces of the explants were covered by one or more layers of non-muscle cells, and the core of the explants consisted mostly of cardiac muscle cells. In a few cardiac muscle cells the myofibrillar organization was disrupted, resulting in the distribution of scattered patches of myofibrils and free myofilaments in the sarcoplasm. A small number of intact muscle cells contained a considerable number of dense granules in the sarcoplasm. At 15 days in culture, a large number of muscle cells showed structural features reminiscent of embryonic cardiac muscle cells. These cells possessed patches of myofibrils, scattered myofilaments and scanty sarcoplasmic reticulum along with other cellular organelles and inclusions. Several of these altered cardiac muscle cells contained mitotic figures. The cardiac explants maintained the initial beating rate until the end of 2 months of culture, except for the 11% of the explants which stopped beating. By 3-4 weeks in culture, most of the cardiac muscle cells possessed the altered cell morphology mentioned above. The explants after 60 days in culture became more flattened than the earlier explants. The intact cardiac muscle cells were rare, and the cores of the explants were mostly occupied by the altered cardiac muscle cells. It is evident from our studies that the cardiac muscle cells have undergone dedifferentiation in long-term culture, and that this dedifferentiation process has yet had no effect in the maintenance of contractility of the explants. Furthermore, these dedifferentiated cardiac muscle cells are capable of DNA synthesis and mitosis.


Fine structure of the cuticle of the desert scorpion, Hadrurus arizonensis. The structure of the sclerite and intersegmental cuticle of the opithosoma of the desert scorpion, Hadrurus arizonensis, has been examined by transmission electron microscopy. The sclerite cuticle contains a four-layered epicuticle, a hyaline exocuticle, an inner exocuticle and an endocuticle. The outer part of the hyaline exocuticle and the whole of the inner exocuticle are constructed of helicoidally arranged planes of microfibrils. Within the endocuticle, the overall architecture is not helicoidal as previously assumed, but consists of bundles of microfibrils oriented horizontally and vertically. Microbibrils of the inner exocuticle and the endocutile are seen as simple unstained rods, but those of the hyaline exocuticle are electron dense rods with an unstained central core. The intersegmental cuticle contains a four-layered epicuticle and a procuticle. In detail, its fine structure differs in most respects from that of the sclerite cuticle. Electron microscopy reveals that hyaline exocuticle, previously assumed to be continuous from sclerite to intersegmental membrane, is absent in the latter.


Fine structure of the epicuticle of the desert scorpion, Hadrurus arizonensis, with reference to location of lipids. The surface and transverse sections of the epicuticle of the desert scorpion, Hadrurus arizonensis, were examined by scanning and transmission electron microscopy, respectively. Sclerite cuticle that was untreated prior to normal EM preparative procedures was compared to cuticle subjected to lipid solvents, high temperature, and concentrated alkali. Surface morphology of untreated intersegmental cuticle was also examined. The epicuticle is composed of four sublayers: outer membrane, outer epicuticle, cuticulin, and the dense homogeneous layer. Lipid solvents did not significantly alter the morphology of any of these layers or the contents of the wax canals that penetrate the cuticulin layer even though the solvents effectively remove lipids from the epicuticle for chemical analysis. The surface of the sclerite cuticle contains amorphous particles, crystalline projections, and scattered openings to dermal gland ducts. Perforations that correspond to the opening of wax canals were faintly visible after extraction of surface waxes and clearly visible after KOH treatment. No openings to dermal gland ducts or wax canals were observed in untreated intersegmental cuticle. However, wax canals are likely obscured by surface waxes similar to those present in sclerite cuticle.


Apolysis and the turnover of plasma membrane plaques during cuticle formation in an insect. The apical plasma membranes of Calpodes epidermal cells have small fattened areas or plaques with an extra density upon their cytoplasmic face. The plaques are typically at the tips of microvilli. The are present during the deposition of fibrous cuticle and the cuticulin layer. Since the plaques are close (less than 15nm) to the sites where these kinds of cuticle first appear, they are presumed to have a role in their synthesis and/or deposition and orientation. When fifth stage larval cuticle deposition ceases prior to pupation, the plaques are lost as the area of the apical plasma membrane is reduced. The plaques pass from the surface into pinocytosis vesicles and multivesicular bodies where they are presumably digested. The loss of plaques occurs as the blood level of moulting hormone reaches a peak at the critical period after which the prothoracic glands are no longer needed for pupation. Apolysis or separation of the epidermis from the old cuticle is the stage when plaques are absent, the old ones have been lost but the new ones have yet to form. After the critical period, the epidermis prepared for pupation with a phase of elevated RNA synthesis at the end of which plaques and microvilli reform in time to secrete the new cuticulin layer and later the fibrous cuticle of the pharate pupa. There is a new generation of plaques for each moult and succeeding intermoult and each generation is involved in two kinds of cuticle deposition before involution and redifferentiation.


Changes in tight junctions of rat intestinal crypt cells associated with changes in their mitotic activity. The freeze-fracture appearance of tight junctions between rat duodenal crypt cells was studied in normal, mitotically suppressed, and mitotically enhanced animals. In normal animals crypt cell tight junctions present a pleomorphic appearance. The population includes junctions resembling postmitotic junctions of the intestinal villus, junctions composed largely or completely of particle chains, and regions at the cell apex in which junctions are absent for 3-4 micron distances laterally. Mitotic suppression by inhibition of DNA synthesis with cytosine arabinoside results in the disappearance of pleomorphism and crypt tight junctions progressively come to resemble those of the intestinal villus. With recovery from the drug and further synchronization with Colcemid, the crypt cells undergo a mitotic burst, and all varieties of unusual junctional configurations are observed with increased frequency.


Cellular junctions of the midgut in the centipede (Scutigerella pagesi) as revealed by lanthanum tracer and freeze-fracture technique. In the midgut of a Myriapoda continuous junctions and gap junctions are described for the first time. Continuous junctions form a belt around the upper two-thirds of each cell. In the intercellular space long and smooth septa are clustered in sinuous strands and intramembrane particles appear on the PF. In the gap junctions the intramembrane particles are located on the EF.