Techniques to increase the response rate in follow-up studies: results of a pilot test. As a part of the design and implementation of a caseload weighting system, Arkansas Rehabilitation Services is adopting a revised client data system. To assess the validity of the data collected in the new system a follow-up survey for recently closed clients has been designed; and to insure the adequacy of the survey design several issues were considered. These included overall survey and questionnaire design. The process, designed to maximize useful information collected with limited resources, resulted in a telephone survey augmented by mail and personal interviews.  The survey procedures and instrumentation were pilot tested for two months with 629 clients. This resulted in major modifications in questionnaire design and brought to light easily adopted procedural improvements resulting in less ambiguity, improved readibility, increased response rate and reduced response bias. Using the described survey methods the investigators observed an overall response rate of 50.8% which compares very favorably with that reported in other studies similar in nature.


[Rehabilitation of chronic obstructive pulmonary diseases at the lung hospital (author's transl)]. The modern lung hospital offers favorable conditions for the rehabilitation of patients suffering from chronic obstructive pulmonary diseases. In the years from 1972 to 1976 2398 patients suffering from chronic bronchitis, bronchial asthma and pulmonary emphysema were subjected to a rehabilitation process at the central hospital for heart and lung diseases Bad Berka. A long-term therapy plan based on a most accurate investigation possible of all the factors which trigger off the complaint in each case was used as baseline. An account is given of the resulting diagnostic and therapeutic program carried out. In the case of chronic obstructive pulmonary diseases it is particularly difficult to assess the effectiveness of rehabilitation measures. One aspect dealt with is the restoration of working capacity. 56.7% of the men and 56.8% of the women were capable of working when they were dismissed. 31.6% of male and 26.4% of female patients were invalids, 11.7% and 16.8% respectively were old age pensioners. Rehabilitation success depended on variables such as age, degree of cardio-pulmonary limitation in performance, as well as on certain concomitant diseases and the patient's cooperation. A decisive factor in some cases was also whether suitable employment could be found for these patients whose age ranges between 40 and 60.


Reintegrating the mentally ill in the community. Substantial reductions in the in-patient census of state hospitals throughout the United States have led to the concentration of large numbers of formerly mentally ill individuals in sheltered living arrangements in local communities. These efforts represent a major change in providing care for the long-term chronic patient. How is the life of this individual affected by community placement? A survey was completed of 499 residents in 234 facilities representing all formerly hospitalized non-retarded mental patients between 18 and 65 years old in California's sheltered care facilities. Results indicate that the social functioning of individuals in the external community is enhanced primarily by the characteristics of the community in which they are placed. In contrast, the social functioning of individuals within the immediate environment of their sheltered living arrangements is most affected by the character of the placement itself. The particular characteristics of communities and facilities found to be most important in addition to the characteristics of the residents which impact on social integration are discussed in the study.


Twelve years spirometric changes among Paris area workers. The effects of smoking habits, socio-occupational factors and respiratory symptoms in the development of airflow obstruction have been studied in a working population of 575 men aged 30-54 in 1960 and surveyed in 1960 and 1972. On average, FEV1 decreased by 47 ml/annum. Apart from FEV1 level, which reflects loss since the beginning of adult life, three factors were independently related to FEV1 slope: tobacco consumption, occupational exposure and social class. The decrease of FEV1 with smoking was dose related and decelerated among those who stopped smoking. This follow-up study ruled against phlegm as a causal factor of early stage airflow obstruction, although its role is not excluded at later stages.


Changing mortality due to strokes in men following treatment of Busselton hypertensives 1967-77. Regular biennial health screenings of the Busselton population between 1966-75 resulted in the recognition of individuals with hypertension and a progressive increase in the adequacy of control of blood pressure in those on treatment. Between 1973-77 observed mortality from strokes (CVA) in males 50 yrs and over declined significantly as might be expected from the smaller numbers at risk from raised blood pressure. No favourable trends occurred in the incidence of CVA in women despite better control of hypertension. In the population as a whole, CVA mortality in untreated or inadequately controlled hypertensives was significantly greater than in normo-tensives or adequately controlled hypertensives.


Prevalence of HBsAg and anti-HBs in the Czech Socialist Republic (CSR). A sample of 1 000 individuals of the urban and rural population of CSR covering all age groups was tested for the presence of HBsAg and anti-HBs. The rates for antigenaemia and antibody prevalence as determined by the RIA method were 1.5% and 12.5%, respectively. The antigen subtype adw was identified. HBsAg findings were significantly more frequent among the urban population, while the prevalence of antibody was comparable in both population types and both sexes. HBeAg was not detected in any case, anti HBe in one.


Evolution of serum immunoglobulin levels during the first year of life in Mozambique. The serum levels of IgG, IgA and IgM as well as total proteins were followed from birth to one year of age in a sample of 44 infants. Values for a 'healthy' population are presented. The results of correlation analysis question current views on the independence of the different immunoglobulin classes.


Poliomyelitis, rubella, and dengue antibody survey in Barbados. A follow-up study. A follow-up study of poliomyelitis, rubella, and dengue antibodies has been made in light of results obtained in a 1972 health and serological survey in Barbados, W.I. Poliomyelitis antibody neutralization tests performed on sera from 307 children under age 15 using overnight serum/virus mixtures on microtiter plates at low serum dilutions revealed the absence of polio antibody at 1:2 dilution in 13.7% for type 1, 6.5% for type 2, and 14.3% for type 3 virus. A significant correlation of the presence or absence of poliomyelitis antibody to types 2 and 3 was seen with the response to immunization histories. Forty-three of 49 girls (88%) given rubella vaccine (RA 27/3) in 1972 had demonstrable haemagglutination-inhibition antibody 4 years later. Neutralization tests for dengue antibody confirmed the results of the complement-fixation tests and indicated that type 2 was probably the sole infecting strain.


The prevalence of osteoarthrosis of the hip requiring total hip replacement in the elderly. A community study of the prevalence of osteoarthrosis of the hip requiring total hip replacement in elderly people is reported. It was found that 5.6% of the population studied had symptoms suggestive of osteoarthrosis of the hip, or had been successfully treated for it. In particular, 0.7% of the survey group had already been operated upon for this condition, and a further 0.5% would have benefited from total hip replacement. An additional 1.3% of the persons studied needed this operation, but were unfit for surgery.


A nationwide survey on thyroid care delivery in Japan, with special emphasis on resources allocation. Results of a nationwide survey show an uneven distribution of 'thyroidologists' and special facilities for the diagnosis and treatment of thyroid disease in Japan. A case is made for more systematic resource allocation in regional planning.


A quantitative index for evaluating patient care with longitudinal data. This paper describes a patient-outcome based index of the quality of health care useful to health services researchers and planners. This index is applicable in any health care situation where longitudinal data are available from patients who can be classified into mutually exclusive stages of severity by functional status, psychological well-being or diagnosis and followed over a period of time. The rationale of the index is presented, along with an illustrative example based on a study on long-term care. The procedure for generating weights for the index is briefly described.


A test of significance for geographic clusters of disease. The geographic pattern of disease has been visually studied by depicting the categorized mortality or morbidity rates on a map. Visual study, however, by no means indicates the statistical significance of observed clusters, i.e., whether or not the geographic aggregations could occur by chance alone. In this paper, an approach for assessing the deviation from chance expectation of the geographic pattern actually observed on the map is described. A simple chi-square test is proposed, and its validity is substantiated by a Monte Carlo approach, which is derived analytically as a special case of Knox's test for space--time clustering. The parameters required for the test are (1) total number of areas, (2) numbers of subareas for each mortality of morbidity category, (3) total number of geographically adjacent areas, and (4) observed numbers of adjacent areas having concordant category pairs.


A stochastic compartment model of stomach cancer with correlated waiting time distributions. The incidence and growth rate of stomach cancer in the US population is modelled, for each sex, as a partially observed, discrete state stochastic process. Explicit evaluation of the transition rates between the states of the model is made possible by identifying them as specific functions of the time spent within each state. The functions used in the model were selected from the medical and epidemiological literature. With the model it was found possible to obtain fits to the age distribution of deaths due to stomach cancer for white males in 1975 and for selected age ranges for white females. These results suggested that the natural history of stomach cancer is different for females above and below age 65.


An exploration of obese observational learning in modifying selected eating responses of obese children. The present study investigated the effects of two observational learning paradigms in modifying the eating behavior of obese children. A total of 18 subjects ranging in age from seven to 12 years and in weight from 74 to 160 lb (33 to 72 kg) were randomly assigned to three conditions. Intervention consisted of four sessions in which subjects viewed videotapes of their baseline eating behaviors compared with a model eating at a reduced speed. Based on the assumption that children may acquire their parents' eating behaviors, one condition included videotapes of a same-sex adult model. In order to maximize model-observer similarity, subjects in a second treatment condition observed videotapes of themselves eating at a reduced speed. Subjects in the control condition viewed only their baseline eating behavior videotapes. Dependent measures of eating behavior were found to be significantly affected by both model treatments, while no significant differences were evidenced in the control group.


Ingestive behavior and composition of weight change during cyproheptadine administration. The effect of cyproheptadine on spontaneous energy intake was studied by means of an automated (liquid diet) food-dispensing apparatus in two nonobese adults confined to a metabolic ward. The experimental design included both single and double-blind periods. Throughout, the composition of daily weight change was determined by the energy-nitrogen balance method. While on cyproheptadine, both subjects exhibited increases in energy intake with the following average composition of weight gain: protein 16%, fat 14% and water 70% (first subject), and protein 5%, fat 49% and water 46% (second subject). The cyproheptadine-induced increase in energy intake was statistically significant in one of the subjects, who was at his desirable weight level at the outset. The other subject was underweight initially and tended to gain throughout the experiment, although rate of weight gain appeared to be more rapid during the periods of cyproheptadine administration. Energy output in both subjects remained fairly constant throughout. We conclude that cyproheptadine induces weight gain of 'normal' composition by stimulating increased energy intake.


A successful behavioral weight-loss program for moderately-retarded teenagers. The present study assessed the usefulness of a behavioral weight-reduction program for moderately-retarded young adults. The behavior treatment involved exposure of 12 subjects to external and self-reinforcement, stimulus control, simplified self-monitoring and energy-expenditure produces over a 14-week active training period. The behavior-therapy subjects lost significantly more weight than a wait-list control group. There was no significant difference in weight lost between behavior-therapy subjects exposed to the techniques live and those exposed to the techniques via video-tape playback of the live sessions. Weight loss for the behavior-therapy subjects containued to occur during five-week maintenance and 16-week follow-up periods.


The development and evaluation of a behavioral weight-reduction program. The development of a comprehensive weight-reduction program and its implementation in the clinic are described. The program consisted of explicit instructions on food monitoring, stimulus control, chaining, exercise, and self-reinforcement. The results of pilot research indicated that the program produced reliable weight loss and that its implementation in a group format was more positive. A formal experiment evaluated the effectiveness of program components in a 2 x 2 factorial design after ten weeks of treatment and at three-month and one-year follow-ups. There was significant weight loss with no main or interaction effects. At follow-up, those exposed to exercise and/or contingency management better maintained their weight loss or continued to lose. Data on the implementation of the program in a clinical setting are presented and these results compare favorably with reports from other clinics using behavior modification. It is suggested that our more positive results may be related to an emphasis on activity and life-style change in addition to changing eating behavior.


Influence of acute thermal stress and maternal diet on metabolic rate of obese (ob/ob) and lean mice at two weeks of age. The metabolic response of one- and two-week-old obese (ob/ob) and lean mice to acute thermal stress, and the influence of maternal diet on body fat and metabolic rates of these mice, were evaluated. Both obese and lean pups increased their rate of oxygen consumption 62 to 67% when exposed to 25 degrees C for 20 minutes rather than to 35 degrees C. Obese pups exposed to an intermediate temperature (30 degrees C), however, increased their rate of oxygen consumption less (35%) than did lean mice (55%) exposed to the same temperature. Reports in the literature suggest that adult obese mice have a markedly reduced ability to increase their oxygen consumption when cold-stressed, but the present results indicate that young obese mice may have less impairment in their capacity to increase oxygen consumption. Two-week-old obese pups contained more fat and consumed less oxygen than lean littermates. The maternal diet was manipulated to increase the body fat content of two-week-old pups to equal that of obese mice, but obese pups still consumed less oxygen than did the lean pups. We, thus, conclude that factors other than differences in body fat content are responsible for the lowered oxygen consumption observed in young obese mice.


Monitoring human eating patterns during the ingestion of non-liquid foods. Relatively few automatic methods have been developed to monitor human eating parameters which may characterize obese 'eating styles'. The methods which have been developed typically require the use of liquid foods unlike those normally consumed. A method is presented for automatically monitoring human eating during the ingestion of typical semi-solid foods. Data obtained using the semi-solid food yogurt suggest that eating rates vary greatly between people but that these rates may be very consistent across meals. Improvements, adjunctive methods and theoretical implications for applied behavior therapy are discussed.


Effect of temperature upon the circular dichroism of bradykinin. Analysis of the effect of temperature on the circular dichroism spectrum of bradykinin has led to a more precise understanding of the solution conformation of the peptide. Circular dichroism and 13C n.m.r. have been used in a complementary fashion to support the picture that bradykinin spends a maximum of about 20% of its time in a partially ordered conformation featuring a gamma-turn with Pro7 as the second residue. Since the gamma-turn probability is insensitive to temperature, some other conformational effect dominated by the structure of water presumably produces the pronounced change in the circular dichroism spectrum with increasing temperature.


Energy-conformation studies of frequency of beta-turns in tetrapeptide sequences. The optimized energies of seven beta-bends, repeating C5 and C7, and right- and left-handed alpha-helical conformations for each of eight tetrapeptides have been computed using empirical methods. Eight tetramers were selected: four helix-forming sequences with hydrophobic residues such as Val, Leu, Ile and Trp, and four helix-breaking sequences with hydrophilic residues such as Asp, Asn and Ser, as determined by their frequency of occurrence in beta turns in proteins. Analysis of the optimized conformations with energies less than or equal to 2.1 kcal/mol from the absolute minimum energy conformer for each tetramer reveals a correlation between low-energy conformations and those predicted from observed protein structures. These results show that energy calculations on small peptide fragments may be usefulin predicting protein structure.


The nature of the multiple forms of bovine thiol:protein disulfide oxidoreductase. Preparations of thiol"protein disulfide oxidoreductase from bovine liver were shown to be homogeneous by polyacrylamide gel electrophoresis, sedimentation equilibrium centrifugation and NH2-terminal analysis (Carmichael et al., 1977). When the enzyme was subjected to prolonged storage at -20 degrees, freeze-thawing, or heating at 60 degrees, at least one new protein species was observed using polyacrylamide gel electrophoresis. The new protein results from dimerization of the enzyme. The dmier consisted of two monomers held together by an intermolecular disulfide bond. The formation of this dimer can be reversed and partially prevented by thiols.


The preferred conformations of protected homodito homoheptamethionine peptides. A1 H n.m.r. study in deuterochloroform medium. Detailed analyses of the conformations of the homo-oligopeptide series, Boc-(L-Met)n-OME n = 2--7, in deuterochloroform have been carried out with proton n.m.r. and IR spectroscopy. Well-resolved high field n.m.r. spectra with assignments for the NH and alpha-CH resonances of these homo-methionine peptides are presented. Extensive n.m.r. concentration-dependent chemical shift studies are combined with IR results to delineate the involvement of the various methionine NH protons in intra- and/or intermolecular hydrogen bonding. N.m.r. chemical shift dependencies with temperature and solvent, DMSO-d6, are used to explore the strength of the hydrogen bonds for the various oligopeptides. At low concentrations, where peptide aggregation is absent, the dipeptide is found to be disordered. The tetra- to heptapeptides possess intramolecular hydrogen bonded seven-membered rings at internal residues. The number of internal rings and the oligopeptide self-association increase with increasing peptide chainlength. At intermediate concentrations associations of peptide molecules with folded structures occur with initial association at the C-terminal region. At high concentrations, "in-register" associated extended beta structures are formed.


Synthesis of N-acetyl-muramyl-L-alanyl-D-glutamic-alpha-amide(MDP) or -alpha-methyl ester derivatives, bearing a lipophilic group at the C-terminal peptide end. We report the synthesis of nine lipophilic derivatives of N-acetyl-muramyl-L-alanyl-D-glutamic-alpha-amide (MDP) or -alpha-methyl ester in which the gamma-carboxyl function of the D-glutamyl residue is either esterified by a medium chain alcohol or substituted by an L-alanyl residue esterified by a medium or long chain alcohol. A new method is described which easily allows one to obtain derivatives of MDP, bearing a free or substituted amino-acyl or peptidyl residue on the gamma-carboxyl function.


Preparation of racemic 2r-carboxy-trans, trans-3,4-dideutero-pyrrolidine (DL-trans, trans-3,4-dideutero-proline) and unambiguous assignment of protons in the 1H n.m.r. spectrum of proline. Racemic trans-3,4-dideutero proline has been prepared by catalytic deuteration of 3-pyrroline-2-carboxylic acid. The stereospecificity of the reduction (i.e. trans to the carboxylic group) was ascertained after transformation of the dideutero compound into the diketopiperazide c/Pro, Aib/, for which unambiguous proton assignments in the 1H n.m.r. spectrum had been obtained previously. The identification of the configuration of the dideuteroproline allows for the affirmation of the correctness of proton assignments as previously proposed in literature.


Extensive modification of protein amino groups by reductive addition of different sized substituents. The amino groups of ovomucoid, lysozyme and ovotransferrin have been extensively alkylated by reacting the proteins with various carbonyl reagents in the presence of sodim borohydride. The extent of modification ranged from 40 to 100%. Essentially monosubstitution was obtained with acetone, cyclopentanone, cyclohexanone and benzaldehyde, while 20--50% disubstitution was obtained with N-butanal and nearby 100% disubstitution was obtained with formaldehyde. Both the methylated and isopropylated derivatives of all three proteins were soluble and retained almost full biochemical activities, but introduction of the larger substituents caused precipitation with lysozyme and ovotransferrin.


Evoked EEG responses in several motor areas of brain to stimulation of hippocampus and caudate, alone and in combination. In curarized rats, electrical stimulation (6 Hz pulses in 6-sec trains) was delivered either to the dorsal hippocampus (Hip), the caudate nucleus (Caud), or to both. Hip and Caud stimulation evoked activity in the motor cortex and the Hip, and the responses commonly grew larger during the stimulation; to a lesser extent, responses occurred in the brainstem reticulum and cerebellar cortex. Combined Hip and Caud stimulation responses were often greater than the responses to stimulation of either Hip or Caud alone, but less than the sum of responses from each single-site stimulation, suggesting occlusive interference because of shared elements in the projection pathways. There were also some instances suggesting mutual facilitation, where the responses to combined stimulation were greater than the sum of the responses to each single-site stimulation. Both kinds of results seem to indicate that the hippocampus, as well as the caudate, has functional connections with motor control areas of the brain and that both areas may interact in motor control.


Degeneration of interneurons in the lateral geniculate nucleus after 5,6-dihydroxytryptamine treatment. Intraventricular administration of the cytotoxic compound 5,6-dihydroxytryptamine produces extensive damage in a small population of neurons in the lateral geniculate nucleus of the cat. The observed changes are characterized by osmiophilic deposits in the cytoplasm and an overall increase in the electrodensity of the matrix. No alterations in the relay cells nor in synaptic endings were observed. The cells affected by 5,6-dihydroxytryptamine, most probably tryptaminergic in nature, belong to the class of interneurons and may correspond to local inhibitory cells described in neurophysiological studies.


Sudden infant death syndrome: a testable hypothesis and mechanism. The Sudden Infant Death Syndrome (SIDS) is the most frequent cause of death in infants aged between one month and one year, yet its cause remains unknown. The present hypothesis is that most infants who die of SIDS have an abnormality of the catecholaminergic system, possible genetically determined, which results in a decreased thermogenic response to cold, owing to a deficiency in noradrenaline (NA), which eventually results in severe hypothermia. A series of complex, but interrelated reactions of the infant to the hypothermia and its consequences leads to death. The final mechanism of regulatory failure involves a deterioration of cardiorespiratory function resulting from hypoxia, metabolic acidosis and hypoglycemia. The etiology of "near miss" for SIDS is also unknown. It is postulated that these infants have a similar but milder deficiency which may be due, in part, to genetic factors. Determinations of central and peripheral catecholamines in "near miss" and normal infants will be performed to test this hypothesis.


The relationships between conceptual and semantic-lexical disorders in aphasia. A nonverbal test of conceptual thinking was administered to 55 normal controls and to 203 patients with monohemispheric brain lesions (74 aphasics and 129 nonaphasic brain-damaged patients), in order to study the relationships between conceptual impairment of aphasic patients and breakdown of the semantic-lexical level of integration of language. A very high number of aphasic patients (54 out of 74) and a limited number of nonaphasic brain-damaged subjects (31 out of 129) obtained a pathological score on the test of conceptual thinking, but only some components of the aphasic symptomatology seemed closely linked to the conceptual disorder. In fact a non-significant relationship was found between conceptual impairment and: ("fluent" or "non-fluent") clinical type of aphasia; severity of aphasic disturbance. On the contrary, a strong relationship was found between conceptual disorder and impairment of the semantic-lexical level of integration of language. These findings seem to show that conceptual disturbance and semantic-lexical troubles are closely linked in aphasia.


Identification of specific neurological disorders using double discrimination scales derived from the standardized Luria neuropsychological battery. The Standardized Luria-Nebraska Neuropsychological Battery has been validated in a number of studies and has shown its effectiveness in making basic neuropsychological discriminations. A major advantage of this battery, compared to other test batteries, is its structure. The test consists of 269 separate items, each of which is designed to measure a different neuropsychological skill. As a result, these items can be combined in a number of ways to form scales aimed at specific neurological processes. It is the purpose of the present study to investigate whether or not the Luria Battery can be successful in discriminating specific neurological disorders by the development of what is termed "double discrimination scales." Using this process, two scales are established to diagnose any given neurological process. The first represents items in which the patients with a specific disorder do worse than a general neurological control group while the second scale represents items in which the patients with a neurological disorder do better than the general neurological control group. For a patient to be diagnosed as having a given process, the patient must score in the proper range on both scales. This method was applied to a sample of 24 multiple sclerosis patients who were compared with 74 patients diagnosed as normal, 106 psychiatric patients, and 101 brain damaged patients. Using the double discrimination procedure, the accuracy of identification of 100% was achieved in all groups. The study supported the usefulness of the double discrimination approach with the Standardized Luria Neuropsychological Battery and opens up the possibilities for scales to be developed for a wide variety of diseases in specific lateralized disorders.


Sero-epidemiological studies on coxiellosis in animals and man in the state of Uttar Pradesh and Delhi (India). The prevalence of antibodies to Coxiella burnetii, the causative agent of Q-fever, was studied in domestic animals either at the farm or at the slaughter house and man in Delhi and Uttar Pradesh (U.P.). Evidence of Q-fever infection was observed in 24.29% of 490 cattle, 16.79% of 536 sheep, 16.02% of 1011 buffaloes, 15.85% of 1937 goats, 14.67% of 184 pigs and 14.29% of 49 street dogs. Twenty percent of 55 dairy cows, 9.52% of 21 dairy goats and 5.71% of 35 dairy buffaloes were found positive for C. burnetii antibodies in their milk. Of 1636 human sera samples tested, 249 (15.22%) were positive. Human sero-positive reactors in U.P. and Delhi were 15.59% and 14.39% respectively. Factors of age, sex, season antibody titres, co-existance of Q-fever and brucellosis and public health significance of high Q-fever infection in meat and dairy animals under the prevalent socio-economic conditions are discussed.


Sero-epidemiologic investigations on brucellosis in the states of Uttar Pradesh (U.P.) and Delhi (India). Sero-prevalence of brucellosis in man and animals was studied during the years 1976 and 1977. Samples were collected from Hospitals/slaughter houses/livestock farms located in Delhi and different districts of Uttar Pradesh (U.P.). The sera samples tested were from 1685 men, 1607 goats, 438 sheep, 244 pigs, 361 cattle, 551 buffalos, 50 dogs, 318 equine and 43 free living animals. The percentage of seropositivity, excluding doubtful ones, was recorded as: man 0.89, goat 5.53, sheep 3.42, pigs 15.98, cattle 6.37 buffalo 4.9 and equine 12.89. Additionally an evidence of agglutinins was also detected in a python serum sample. It was observed that occupation, age, sex and season had a bearing on the prevalence of the disease.


Toads as reservoirs of salmonellae: prevalence and antibiogram. Of 570 intestinal-content-samples of toads examined, 40 yielded salmonellae, which included 26 strains of S. goverdhan, 9 of S. bareilly, 2 of S. richmond, and 1 each of S. typhimurium, S. weltevreden and S. newport. From 52 visceral-organ samples, 6 strains of S. goverdhan and 1 of S. typhimurium were isolated. Antibiotic sensitivity studied against 18 chemotherapeutic agents, revealed that although the isolates were sensitive to most of the antibiotics, all of them were resistant to bacitracin, novobiocin and oleandomycin. To sulfonamides, erythromycin and pencillin, respectively, 42, 8 and 3 isolates were resistant.


Leptospirosis in the city of Salvador, Bahia, Brazil: a case-control seroepidemiologic study. From January 1 to December 31 of 1975, all patients admitted to Salvador's Infectious Disease Hospital were serologically tested for leptospirosis if their clinical and laboratory findings were compatible with this diagnosis. Of the 888 patients tested, 133 were positive. Among patients with an initial clinical impression of leptospirosis, the diagnosis was confirmed serologically in 36% and for the 133 leptospirosis patients, only 67 (50.4%) were initially suspected. Epidemiological aspects investigated covered: age, sex, place of residence and occupation for all cases and for fatal cases; distribution of cases by month of occurrence and by rainfall in that month; distribution of serotypes by month; and probable source of infection with emphasis of the occurrence and type of contact with dogs. For each case residing in Salvador, a control of the same age and sex was interviewed in the immediate neighborhood. Sewage, rats, water, dogs, mud and garbage were identified as the most likely source of infection in that order. Marked seasonal fluctuations were apparent with peak incidence during the months of maximum precipitation. In two-thirds of cases reporting contact with a dog, tests on the animal revealed the same serotype. The most frequent serotypes were: icterohemorrhagiae, autumnalis, castellonis, grippotyphosa, hebdomadis and bataviae.


The need for integrated control programs for zoonoses affecting livestock. Prior to recognition of etiologic agents of zoonoses (infections transmitted between animals and man), physicians encountered these illnesses in man and veterinarians observed them in animals. As the agents were identified, interspecies relationships (and spread) became evident and control programs evolved without consideration of cost-effectiveness. Today, the public demands efficient use of financial resources. Human health as well as economic losses are concerns of animal health agencies. Zoonoses affecting livestock, though not major priorities among public health agencies, cannot be ignored. It seems economical, therefore, to combine the efforts of these agencies in zoonoses control. This would benefit human health by reducing the animal reservoirs and the livestock industry will benefit by lowered production costs.


Contact B-scan ultrasonography: a practical approach. The Bronson-Turner ultrasonoscope is an extremely practical, simple ultrasound device for the clinician. Used with real time, gray scale, and three-dimensional thinking, this unit has gained wide acceptance. It is designed primarily for clinical diagnostic ocular examination; with experience, it can be used for orbital interpretation as well. Axial length measurement with this instrument is only approximate.


Immersion ultrasonography: simultaneous A-scan and B-scan. In eyes with opaque media, ophthalmic ultrasound provides a unique source of information that can dramatically affect the course of patient management. In addition, when an ocular abnormality can be visualized, ultrasonography provides information that supplements and complements other diagnostic testing. It provides documentation and differentiation of abnormal states, such as vitreous hemorrhage and intraocular tumor, as well as differentiation of orbital tumors from inflammatory causes of exophthalmos. Additional capabilities of ultrasound are biometric determinations for calculation of intraocular lens implant powers and drug-effectiveness studies. Maximal information is derived from ultrasonography when A-scan and B-scan techniques are employed simultaneously. Flexibility of electronics, variable-frequency transducers, and the use of several different manual scanning patterns aid in detection and interpretation of results. The immersion system of ultrasonography provides these features optimally.


Carcinosarcoma of the esophagus: a case report and review of the literature. A case of carcinosarcoma of the esophagus and a review of literature are presented. The pertinent clinical and pathological data are summarized. There have been 51 reported cases of which 31 underwent surgical resection of the lesion; there have been three five-year survivors. Although the cumulative experience with this malignancy is limited, it is apparent that the presentation and clinical course of this tumor is not substantially different from the more common squamous cell carcinoma. Therefore, the diagnostic and therapeutic management should not vary from that of any malignant esophageal lesion.


Cystic hamartoma of the liver.

Cystic hamartoma of the liver. A case of cystic hamartoma of the liver is reported. The clinical presentation and management is discussed. A review of the origin of this rare tumor and its clinical and pathological characteristics is made.


Surgical treatment of a solitary giant hemangioma of the liver presenting as an avascular mass. A clinically silent giant hepatic hemangioma was diagnosed following, and as a result of, minor trauma. Liver scan, arteriography and liver biopsy were suggestive of an avascular mass, but laparotomy established that the tumor was a hemangioma. Surgical treatment and complete recovery followed. These benign primary hepatic tumors are usually discovered incidentially. Their presentation and management are discussed.


Leiomyoma of duodenum: report of a case. A case of a large leiomyoma of the duodenum and how it presented is reported. Difficulties in making a preoperative diagnosis and the surgical approaches to its treatment are discussed.


Small intestinal obstruction by an enterolith from a Meckel's diverticulum. A new case of an enterolith, formed within a Meckel's diverticulum and subsequently expellefferential diagnosis from a gallstone ileus is virtually impossible. This nevertheless remains a rare cause of intestinal obstruction.


Acute pancreatitis in a community with a low alcohol intake. The etiological factors in 130 cases of acute pancreatitis occurring in a community with a low alcohol intake were reviewed. Alcohol was an insignificant factor in the etiology of acute pancreatitis. So-called idiopathic pancreatitis, occurring mainly in the older age group, was diagnosed in 19% of the cases. This is in contradistinction to findings in populations with excessive alcohol intake, where idiopathic pancreatitis is seen in all age groups. Similar age and sex distribution, as well as biochemical evidence of cholestasis, were seen in both the group suffering from gallbladder disease and in the idiopathic group. A more aggressive diagnostic work-up, including surgical exploration, is warranted, in view of the clinical overlap of biliary tract disease and idiopathic pancreatitis.


Leiomyosarcoma of the rectum: diagnostic criteria and surgical approach. A case of leiomyosarcoma of the rectum is reported. There was difficulty in establishing the correct histologic diagnosis. Diagnostic criteria, including electron microscopy examination, are reviewed. Abdominoperineal resection of the rectosigmoid is the common therapeutic procedure recommended.


Surgical treatment of pulmonary metastases. Pulmonary metastases from many primary sources were treated by surgery in 42 patients. The seven-year survival rate was 10%. A long time interval between the operation on the primary tumor and the metastatic lung lesion was associated with a better prognosis. The survival rates for patients with carcinomas and sarcomas were nearly equal equal after removal of pulmonary metastases. The patients with melanoma died soon after lung resections. The location of the metastases in the lower lung lobes had a better prognosis than that of metastases in the upper lobes. In this material there was a patient who, after treatment of the primary tumor, needed three thoracotomies to remove eight pulmonary metastases from both lungs. The patient was alive and free from all signs of recurrence 20 years after the first removal of pulmonary metastases.


A complication of Lahaut's operation for prolapse of rectum. Complications following Lahaut's procedure for rectal prolapse have not been documented. Two cases in which a potentially fatal complication occurred after this operation are described.


Esophagectomy and esophageal replacement by gastric pull-through procedure. The gastric pull-through procedure is a relatively new surgical technique for carcinomas of the hypopharynx and cervical esophagus and benign diffuse stricture of the thoracic esophagus, that require total esophagectomy. This technique is original both in the exeretic and reconstructive phase: total esophagectomy is performed by blunt dissection; thoracotomy and pleural damage are avoided. The basic principle of the operation is the gastric transposition into the neck through the posterior mediastenum and a pharyngogastric or esophagogastric anastomosis, according to the type of disease. Fourteen of our cases who underwent a gastric pull-through are presented and discussed.


Amebic necrosis of bowel.

Amebic necrosis of bowel. Ten cases of amebic necrosis of bowel have been presented. The pathology of amebic bowel necrosis has been discussed in detail, and diagnostic criteria have been mentioned. The treatment of choice in these cases is wide excisional surgery.


Sincipital nasofrontal encephalomeningocele. A case of a 7-year-old male child with sincipital nasofrontal encephalomeningocele is reported. The anomaly was associated with a mild degree of atrial septal defect. This is the first case reported in the Cameroons.


The importance of vaginal infection on recurrent cystitis in women. Forty-one women with a clinical history of recurrent urinary infection were studied. The aim of this study was to correlate the importance of vaginal infection and theincreased incidence of urinary infection. By using statistical methods, we came to the conclusion that the presence of vaginal infection is not related to the recurrence of urinary infection. Vaginal contaminations certainly permit the increase of urinary infection; there must be other host-related factors, however, that are more important for the recurrence of urinary infection.


Alkaline reflux gastritis associated with abnormalities of the gastrojejunostomy. Alkaline reflux gastritis is presently accepted as being part of the postgastrectomy syndrome complex. Our experience with this entity has revealed a frequent association of alkaline reflux gastritis with functional or organic abnormalities of the gastric remnant and/or newly formed gastrojejunostomy. The role alkaline reflux gastritis plays as a separate entity in the symptomatic patient remains to be clinically determined.


Penetrating cardiac injury by wire thrown from a lawn mower. The first successful surgically treated case of penetrating heart injury, specifically the right ventricle, caused by a fragment of coat hanger wire thrown by a lawn mower, is reported. Though traumatic heart injuries are rare, this case represents accurate surgical management and judgment, especially in the preoperative phase which resulted in early operating and excellent postoperative results. It is our feeling that if the patient can be transferred safely to the operating room the mortality rate is considerably lowered; however, emergency room thoracotomy, which will undoubtedly result in a greater survival rate from these spectacular injuries, should be performed in the emergency center if cardiac activity ceases or the patient's condition deteriorates considerably.


Closure of splenic bed after splenectomy in cases of huge splenomegaly. After splenectomy, in cases where large spleens are present, a raw surface is left behind with an accumulation of serous sanguinolent material that may lead to complications. The authors report a technique to obliterate and peritonealize the splenic fossa after splenectomy for huge spleens. Twenty-one cases are reported, in which no complications from bleeding, subphrenic collections or pleuropulmonary complications were noted.


Intralesional steroids in conservative management of subglottic stenosis of the larynx. Subglottic stenosis after prolonged endotracheal intubation is a well recognised complication, especially with the advent of intensive resuscitative techniques. Although prevention is the best cure, once the management has been established it should be conservative in the first instance, especially in the case of children. The successful treatment of four cases with this complication is reported. The treatment consisted of intralesional injection of Triamcinolone Acetonide Aqueous Suspension (Kenacort A), dilatation with gum elastic bougies, bronchoscopy and very limited surgical correction in one case. A brief reference is made to the etiological factors and to the mechanism of action of steroids in scar tissue.


Extensive sarcoidosis involving the upper respiratory tract. Sarcoidosis is a multisystem granulomatous disease without pathognomonic symptomatology or pathology. It may involve the upper respiratory tract, but this manifestation is rarely threatening. A case is reported here, in which extensive destruction of the larynx due to involvement by sarcoidosis necessitated tracheostomy. A review of the literature and a discussion of the therapeutic considerations are presented.


Parathyroid cyst and hyperparathyroidism. A case report of a parathyroid cyst with high calcium levels which dropped to normal after excision of the cyst, and a short discussion of the literature is herewith presented. It is believed that this case presents the rare association of a parathyroid cyst and hyperparathyroidism.


Non-functioning carcinoma of the adrenal cortex. A case of non-functioning carcinoma of the adrenal cortex is reported. This type of neoplasm is rarely seen; up to 1974 only 173 similar cases had been reported. The patient has survived for nine months following diagnosis and operation.


Thyroid lesions in patients with hyperparathyroidism. Twenty of ninety patients with hyperparathyroidism had associated pathology of the thyroid gland. Three carcinomas of the thyroid were found incidentally at the time of surgery for hyperparathyroidism. The association of thyroid lesions and hyperparathyroidism was frequently reported and explained previously on the basis of hypercalcemia acting as a goitrogen. Current evidence, however, suggests radiation as a strong probable factor in the production of this association. Attention should be given to the thyroid gland and of dominant nodules inspected. Concomitant management of those nodules according to the degree of suspicion they arouse, should be undertaken at the time of neck exploration for hyperparathyroidism.


Congenital thymic cyst in the neck.

Congenital thymic cyst in the neck. Cervical thymic cysts are rare. Thirty-four cases are reported in the English literature. Persistence of a part of thymopharyngeal duct may lead to the cyst formation in the neck. The majority of the cysts are seen in children under 10 years of age. There is marked variation in the size of the cysts. The majority of them are multilocular and the color of the fluid varies widely. The epithelial lining is variable; the majority of the cysts show stratified squamous epithelium. The characteristic histological features are Hassal's corpuscles, cholesterol crystals and aggregates of lymphocytes. Our patient was a four and a half year old female; she presented with a four month history of a painless swelling in the neck. The multilocular bluish-black cyst excised from the left side of the neck had all the histological features of a thymic cyst. A pre-operative diagnosis of such a cyst can be made only by bearing in mind the possibility of thymic remnants in the neck.


Surgical experience of closure of ventricular septal defect with special reference to the transatrial approach. One hundred patients underwent closure of ventricular septal defect (VSD) during the years 1964-1977. The right transventricular approach was used in 92, the left ventricular in one, the pulmonary artery in one and the transatrial in the remaining 18 patients. Six patients (5.3%) died following operation. All of them suffered from severe pulmonary vascular resistance. Six patients have been reoperated successfully because of residual shunt. The transatrial approach is being used at present as a routine for closure of types II and III of VSD, particularly in patients with pulmonary vascular resistance. All the surviving 106 patients are in class one and two of the NYHA. At present, closure of VSD in asymptomatic patients is being performed electively at the ages of three to five, whereas symptomatic children, with high pulmonary vascular resistance and heart failure not responding to medical treatment, are operated on early in life usually with the use of deep hypothermic arrest.


Aneurysm of the splenic artery.

Aneurysm of the splenic artery. Two cases of multiple aneurysms of the splenic artery are reported. The aneurysms themselves were asymptomatic and the patients were operated upon for other reasons. In the first case the aneurysm was of an arteriosclerotic nature and in the second it coexisted with portal hypertension. The literature on this subject is briefly reviewed.


Influence of ketamine anaesthesia on renal and cardiovascular functions in mongrel dogs. Cardiac minute volume, renal blood flow, pulse volume, heart rate and urinary output were determined by means of experiments made on 10 mongrel dogs. Anaesthesia was maintained by nitrous oxide/oxygen mixture administered with Ketamine. Under the conditions described it was observed that -- contrary to what is found in human patients -- cardiac and renal minute volume as well as pulse volume are significantly decreased. No significant changes has been observed in the heart rate. Whilst urinary output was decreased, the excretion of individual electrolytes was found to be different.


Polymeric pyelotomy (experimental studies). A non-toxic, soluble polymeric preparation MAG with controlled period of gelation was synthetized for the extraction of stones from the pyelocalyceal system during surgery for urolithiasis. With respect to toughness the preparation proved superior to the fibrinogen-thrombin mixture, used in the so-called "fibrin pyelotomy" according to Dees. Its biologic testing in animals (rabbits, dogs and pigs) yielded excellent results.


Mesenteric arterial steal syndrome secondary to bilateral lumbar sympathectomy. A case of acute mesenteric ischemia and massive intestinal infarction secondary to bilateral lumbar sympathectomy and without any other apparent precipitating factors is presented. Its characteristics and findings significantly agree with those described as part of the mesenteric arterial steal syndrome. Although this syndrome was originally described as secondary to surgical revascularization of the lower extremities, experimental studies have shown that lumbar sympathectomy, by means of reducing the peripheral vascular resistance in the lower extremities, similarly causes intense hemodynamic alteration of the mesenteric circulation due to the sudeen redistribution of blood flow to the lower limbs at the expense of the mesenteric flow. When marginally compensated occlusive mesenteric arterial disease exists prior to surgery, the sudden fall in the arterial pressure gradients in this vessel can precipitate the occlusion of these arteries, resulting in mesenteric ischemia and intestinal infarction. It has also been suggested that an intense vasospamodic neurogenic reflex in the mesenteric arteries is an important factor in the pathogenesis of this syndrome.


My experience in the management of esophageal cancer. Between 1946 and 1974 we carried out 1,174 resections of the esophagus for cancer in the upper and middle thoracic segment. Through early diagnosis and the combination of preoperative irradiation therapy and antethoracic anastomosis, divided into three stages when necessary, the operative mortality was decreased (6.0%), and the survival rate was increased. The five-year survival rate was 10.8% for men and 29.3% for women.


Unusual presentation of ruptured splenic artery aneurysms. Two cases of ruptured splenic artery aneurysms with unusual clinical presentation are reported. In one case an inflammatory abdominal process was suspected, while in the other the operation was delayed by several hours due to the unexplained coma, high blood sugar levels and lack of signs of shock until an advanced stage of the disease. As there was no active bleeding during the operation, the presence of free blood in the abdomen and clots in the omentum provided the clue for localization of the source of the bleeding.


Benign polyps of the ureter.

Benign polyps of the ureter. Polyps of the ureter are benign primary tumors of mesodermal origin. These are less common because the majority of benign tumors are epithelial in origin [2-10]. Two cases are described here. The differential diagnosis and the management of fibrous benign polyps of the ureter are discussed.


Carcinoma of the prostate. I. Histochemical examination as an aid in evaluating prostate carcinoma. In 26 patients with carcinoma of the prostate (CaP) the histochemical and histological characteristics of the tumour were compared with the clinical course in both untreated patients and in those receiving hormonal therapy. In the control group 16 patients with BPH were examined in the same way. It was found that histological types of CaP cannot be identified by grading. Higher frequency of very strong LDH activity in CaP was the only distinction against BPH.


Carcinoma of the prostate. II. Serum activity of acid phosphatase, prostatic acid phosphatase, LDH and its isoenzymes. In 25 patients with carcinoma of the prostate (CaP) T3 and in a comparative group of 18 patients with BPH the serum enzymes of AP, tartrate labile AP, LDH, and iso-LDH were investigated simultaneously in basal conditions and after standardized transrectal prostatic biopsy. AP, PAP as well as LDH were shown to be of small diagnostic aid. The reaction of serum enzyme levels following the standardized prostatic biopsy was the same in both CaP and BPH patients. In studying LDH-isoenzymes, we found that the third fraction was elevated in almost all patients. This change is apparently not of prostatic origin, and we could not attribute it to the concomitant diseases found in some patients.


The vaginal influx and its significance in the diagnosis of infections of the urinary tract. The vaginal influx during miction is a frequent phenomenon. In our clinical study it showed a rate of 54 per cent. The significance of pathomorphological substrates is diminishing with the advancing vesical descensus. The posture during miction has but little influence on the vaginal deviation of the urinary stream. The mid-stream urine is relevantly contaminated in every other girl and, therefore, it may be used only for screening. Indication for an antibacterial therapy is based on catheter or puncture urine.


The predictive value of 5'-adenine nucleotide depletion and replenishment in ischaemic rabbit kidney tissue. Renal ischaemia produced by clamping of the blood vessels in situ for periods of 10 to 150 minutes resulted in a progressive depletion of the total content of adenylates in the kidney tissue (sigma ATP, ADP, AMP). Initial dephosphorylation of ATP and ADP, resulting in further catabolism of AMP to hypoxanthine and xanthine, accumulated in the ischaemic tissue. The postischaemic ability of the kidney tissue to functional regeneration was in correlation with the ischaemic adenylate loss (r = +0.94, P less than 0.001) as well as the accumulation of hypoxanthine and xanthine (r = -0.90, P less than 0.001). The initial adenylate resynthesis rate was constant during recovery (0.5--0.8 mumol/g . h-1), independent of the duration of the preceding ischaemia. Determination of the postischaemic adenylate regeneration thus gave no additional prediction of the reversibility of the ischaemic parenchymal damages.


Nephrotic syndrome induced by D-penicillamine therapy. The paper presents a female patient in whom the penicillamine therapy for aggressive hepatitis triggered off the development of nephrotic syndrome. Histological findings revealed membranous glomerulonephritis. After the withdrawal of penicillamine therapy, the laboratory results returned to normal. The authors concluded that penicillamine should only be administered in conditions in which other means of therapy prove inefficient (i.e. Wilson's disease, cystinuria associated with calculi).


IgA glomerulonephritis. Mesangial IgA deposition without systemic signs (Berger's disease). Renal biopsy specimens from 204 patients with glomerulonephritis or nephrotic syndrome have been studied. In ten of the patients not suffering from acute poststreptococcal glomerulonephritis, systemic lupus erythematosus or Schönlein-Henoch syndrome, diffuse, selective mesangial IgA deposition was observed. Clinically, persistent microscopic haematuria, mild proteinuria and, except in one patient, normal renal function were found. Light microscopically the histological picture was dominated by a diffuse or focal increase in volume of the mesangial matrix, and mild mesangial cell proliferation. Exceptionally, there was also crescent formation. Immunofluorescence revealed large IgA, IgG and C3 deposits, as well as small IgM and fibrinogen deposits in the mesangial glomeruli. The authors' assumption that immunocomplexes containing a secretory component might be implicated in the pathomechanism of Berger's disease, could not be proved.


[Examination of the retest reliability of the findings of the first psychopathological examination (AMP system)]. 80 inpatients were interviewed two times by the same rate during 24 h. Using Kappa, the retest reliability of the following parts of the psychopathological findings was determined: (1) aspects of the interview (median 0.54); (2) AMP symptoms (median 0.72); (3) AMP syndromes (median 0.79); (4) clinical syndromes (median 0.77), and (5) nosologic diagnoses (median 0.93). Based on structured rating of the psychopathological symptoms, a good retest reliability was found.


Trazodone intravenously administered and plasma prolactin levels. Plasma prolactin levels during intravenous Trazodone infusion have been evaluated. Although the modifications were not statistically significant, a slight decrease of plasma prolactin levels was noted. This result suggests that Trazodone has no remarkable effect on hypothalamic function.


[Treatment of therapy resistant depressions with high dose clomipramine]. 50 so-called therapy-resistant depressed inpatients have been treated with daily i.v. infusions of Clomipramine in a high dosage, using a fixed therapy schedule with increasing and decreasing dosage ranging from 250 to 500 mg. The majority of the inpatients showed sufficient or good therapeutic effects, notable side effects were rare. The therapeutic possibilities of so-called therapy-resistant depressions are discussed.


[Folliculitis granulomatosa perforans profunda: an independent perforating dermatosis?]. A peculiar perforating dermatosis was observed in two adolescent male patients consisting of a persistent, disseminated, asymptomatic, follicular, discretely hyperkeratotic papular eruption. Histologically a massive granulomatous panfolliculitis was present with partial destruction of the pilary complex and occasional perforation of hairs through the infundibular wall. Aggregations of keratin fragments were scattered throughout the corium. These histological findings clearly separate the condition from perforating folliculitis, pityriasis rubra pilaris and Kyrle's disease. Differentiation from the perforating type of keratosis pilaris is more difficult.


[Omphalolith].

[Omphalolith]. In rare instances a hard, smooth, almost black bolus, "omphalolith" is found in the umbilicus, resembling a malignant melanoma. After removal by a pincette it reveals on its backside a colourless lamellar epithelium. At microscopic examination it also constists of stratified corneocytes. Differential diagnosis of the omphalic stone includes the so called umbilical cholesteatoma, an accumulation of crumbling, fetid masses in the umbilicus, often times accompanied by seborrhea which may lead to abscess formation. The term omphalic stone could not be found in the medical literature. However, it has been used to name a jewel which is worn in the umbilicus or a huge stone in Delphi which was believed by our ancestors to be the center of the world.


[Infection in man and dog with the mite, Cheyletiella yasguri Smiley]. The infection with the mite Cheyletiella yasguri Smiley in 3 dogs and 5 out of 6 persons exposed to infestation is reported. Two of the dogs appeared to have been infected during a stay in a kennel. The dogs presented with moderate itching and slight to massive floury squamation on the back. In the infected persons, excoriated papules were present on the body and the extremities. The itching, which had persisted for 4--12 months, disappeared in all cases a few days after the dogs had been removed from the house. In the dogs, three antiparasitic baths were sufficient to exterminate the mite population.


[Vaccinia autoinoculata during pregnancy]. A 21 year old woman received a smallpox revaccination during the fifth to sixth month of pregnancy. She developed accidental vaccinia by autoinoculation and, five weeks later, gave birth to a healthy child.


[Nevus of the arrector muscle of the hair]. An eighteen year-old-male patient had an asymptomatic nevoid lesion with small papules over the right lumbosacral region. The nevus was diagnosed histologically as a nevus musculi arrector pili, the origin of which is seen in a nevoid hyperplasia of the smooth muscle bundles (mm. arrector pili) connected with hair follicles.


Microphotometric determination of glycogen in single fibres of human quadriceps muscle. A technique for the quantitation of glycogen in single fibres of human skeletal muscle is described. By using microphotometry the loss of glycogen from cryostat sections during a PAS-staining procedure was shown to be negligible. Further, it was found that nearly all the PAS-positive material (98.5%) inside a muscle fibre is glycogen. A significantly higher mean glycogen concentration (P less than 0.001) was found in type II fibres than in type I fibres in the resting quadriceps muscle of sedentary young males. The coefficient of variation for the glycogen concentration within each fibre type was found to be 17% and 15% for type I and type II respectively. The specificity of the PAS-staining technique for glycogen was confirmed by a statistically significant correlation (r = 0.78, P less than 0.001) between the glycogen concentration measured biochemically and that calculated from microphotometry and area and thickness measurements. With the technique described, it seems possible to measure the glycogen concentration of single muscle fibres in serial sections and to calculate this in standard biochemical terms.


Succinate dehydrogenase activity in the developing molar of the hairless mouse Mus musculus. Succinate dehydrogenase activity in the odontogenic tissues of the hairless mouse (hr/hr) has been studied from the initiation of the dental lamina through apposition. Enzyme activities were designated as negative, slight, moderate and strong as a function of intensity of the reaction product. Enzyme levels in the odontogenic tissues increased with advancing tooth morphogenesis. Greatest activity was observed in the ameloblastic layer which peaked on the fourth to sixth postnatal days. This cell layer displayed higher enzyme activity than the ectomesenchymally-derived odontoblasts. Succinate dehydrogenase activity appeared to be related to the degree of differentiation and functional competence on the odontogenic tissues of the hairless mouse.


A quantitative cytochemical study of acid phosphatases in rat liver parenchymal cells of different ploidy values. The Vickers M86 integrating microdensitometer has been used to quantify the cytochemical reaction for acid naphthol AS-BI phosphatase activity in isolated, rat liver parenchymal cells. Data are presented which validate the method. The use of this method together with that of the Feulgen reaction to estimate nuclear ploidy value in the same cell, has shown that there is an increase in acid phosphatase activity of up to 100% when the euploidy value of the liver cell doubles. It has been further shown that 70--80% of this enzyme activity is ouabain-sensitive, regardless of the euploidy value. The data may be interpreted to indicate that the extra gene copies of the polyploid cells are operative.


A histochemical study of catecholamines and cholinesterases in the autonomic nerves of the human minor salivary glands. The cholinergic and adrenergic innervation of human minor sublingual, buccal and labial salivary glands has been studied with histochemical techniques for localizing acetylcholinesterase and catecholamines. A rich cholinergic innervation was observed around the acini, blood vessels and some ducts of the three glands. The adrenergic innervation, however, was virtually absent from the parenchyma although present around the blood vessels, in marked contrast to the dense parenchymal adrenergic innervation observed in the human parotid and submandibular glands. These results suggest that the autonomic nervous mechanism which regulates salivary secretion is more elaborate in the major than in the minor salivary glands.


Adenylate cyclase cytochemistry: a methodological evaluation. A cytochemical method for the demonstration of adenylate cyclase activity has been evaluated. Enzyme activity in the epithelium of the Müllerian part of the vaginal anlage in neonatal, oestradiol-treated mice has been studied under different experimental conditions. The effects of fixation, incubation conditions and post-fixation have been studied. Variations in the amount of impurities and acid content of the glutaraldehyde do not seem to influence the enzyme activity. High Pb2+ ion concentration seems to promote unspecific staining. Under standard conditions [2 mM Pb (NO3)2' pH 7.2, and incubation temperature 30 degrees C], neither non-enzymatic nor nonsubstrate-dependent lead trapping in the tissue could be observed. The possible contribution of other enzymes utilizing ATP and AMP-P(NH)P as the formation precipitate, has been evaluated. Both ATP and AMP-P(NH)P have been used as substrates in this study. Provided the appropriate control experiments are performed, this cytochemical method is reliable for demonstration of adenylate cyclase activity.


Glycosaminoglycans in the touch corpuscle of the dog. Alcian Blue staining of the touch corpuscle of dog skin indicates that glycosaminoglycans are present as globular masses in some of the basal cells and are also seen in high concentration in the connective tissue core. The function of these basal cells is not clear but they may be responsible for the production of the large amount of glycosaminoglycan present in the underlying dermis.


A quantitative microdensitometric and autoradiographic study of the effect of 4'-demethyl-epipodophyllotoxin-beta-D-thenylidene glucoside (VM-26) on the cell cycle of cultured fibroblasts. The effect of 4'-demethyl-epipodophyllotoxin-beta-D-thenylidene glucoside (VM-26) , a semi-synthetic derivative of podophyllotoxin, on the cell cycle was studied with chick embryo fibroblasts cultivated in vitro. DNA, RNA and protein content, as well as NADH-diaphorase activity were determined by quantitative microdensitometry and cytofluorometry. The incorporation of [3H]thymidine and [3H]leucine into DNA and proteins were analysed by autoradiography. These metabolic data correlated with morphological observation showed that VM-26 blocks the cell cycle at different moments of its kinetics depending on both the dose and the time exposure. NADH-diaphorase activity is the first to be affected, then biochemical changes (involving the metabolism of RNA and proteins) and morphological alterations (especially of mitochondria) follow. This suggests that VM-26 may act primarily upon the mechanism of respiration of the cell.


[Closure of tracheo-esophageal fistulae after chronic intubation (author's transl)]. Tracheo-esophageal fistulae caused by prolonged intubation can be life-threatening to the patient involved. Older techniques for the closure of these fistulae were generally unsafe in infected tissues, were replete with complications, and had to be done in multiple stages. We describe a single-stage procedure for closure of posterior tracheal wall defects. A partially deepithelialized cervical flap is rotated between the sutured esophagus and the trachea. This reconstructed posterior wall is resistent to the presence of a cannula. In order to prevent recurrence of the fistula (if further respiratory treatment is needed), a small nasogastric tube or a long Penrose drain placed in the esophagus should serve as feeding tubes.


[Closure of recurrent perforations of the tympanic membrane (author's transl)]. In 20 patients with recurrent perforations of the tympanic membrane after tympanoplasty, closure was attempted with a fibrin tissue adhesive and in 15 this was successful. This method is recommended for the office out-patient treatment of recurrent tympanic membrane perforations.


[Head and neck injuries in equestrian accidents (author's transl)]. Horses' kicks can produce two types of head and neck injuries: injuries of the mid-face and injuries of the larynx. Typical cases as seen by the author are presented. The treatment of mid-face injuries is performed according to principles of plastic surgical repair. After frontal-nasal injuries, a revision of the nasal septum must be done. Involvement of the larynx requires external layer repair of mucosa and cartilage.


[A report of a fractured ossified stylohyoid ligament (author's transl)]. An incident of a fractured ossified stylohyoid ligament is reported. The symptoms and the method of diagnosis are described. Treatment was surgical resection of 1 cm of the ossified ligament.


[Objective diagnosis of recruitment by brainstem audiometry (author's transl)]. The differential diagnosis in cochlear damage with brainstem potentials is easily done by looking for normal latencies that coincide with substantial hearing loss. Further validation can now be achieved with methods representing Fowler and SISI test equivalents. Amplitudes of brainstem potential were compared in 28 patients with marked differences of hearing loss in either ear. Amplitudes are balanced at the stimulus intensity corresponding to subjective loudness balance (Fig. 3). Intersubject comparison of input/output function steepness is not advisable because of the greater interindividual variation of amplitudes (Fig. 2). Amplitude modulation by short Gauss-shaped increments (Fig. 1) or by decrements of a continuous tone evokes clear brainstem potentials at thresholds of about 5dB above subjective detection, but it also depends upon stimulus duration or steepness (Fib. 4), frequency (Fig. 5) and the degree of modulation (Fig. 6). With a cochlear hearing loss of more than 40dB, a 1 dB increment evokes potentials for continuous tone intensities higher than 20 dB above subjective thresholds (Fig. 7). This test is mainly useful for children with retarded language development and lacking a stapedius reflex, for adults, who cannot sufficiently cooperate, and where there is a prolonged latency due to middle ear damage or a steep high frequency loss.


Volume shifts with partial submersion of isolated lung lobes. When an isolated lung lobe is partially submerged, volume moves from the submerged part to the unsubmerged part. We partially submerged isolated dog lobes of known weight and volume, and measured airway pressure and, by water displacement, the volume of the submerged part. The lobe was then air-dried and sectioned at the waterline and each part weighed. Multiplying lobar volume by the fractional weight of the submerged part yielded the volume of the submerged part before immersion, and therefore the volume shift to the unsubmerged part due to immersion. Dividing this volume shift by the immersion-induced change in airway pressure gave the compliance (Cr') of the unsubmerged part. Cr' was compared to Cr, the compliance of the unsubmerged part when it was inflated with air. Cr/Cr' was linearly related to the degree of immersion: as immersion increased Cr/Cr' fell; so when lobes were 80% immersed Cr/Cr' was 0.3--0.5, indicating that compressing the lower part of the lung made the upper easier to expand. This behavior could be explained if with immersion lung units moved from the submerged part to the unsubmerged part and this shift increased with the degree of immersion. We demonstrated that when one part of a lobe was compressed lung units moved away from the compressive force and that this movement could occur without similar movement of the pleural surace. Tissue movement probably accounted at least in part for our results.


Use of microspheres in measurement of regional blood flows during +GZ stress. The use of the radiolabeled microsphere technique for the study of the effects of +GZ acceleration on regional blood flow is examined. A theoretical analysis of the limits of this technique in a high acceleration environment is presented. Chronically implanted, electromagnetic, aortic flow probes were used to determine the relationship between aortic blood flow velocity and +GZ acceleration in conscious adult miniature swine. It was found that conscious straining adult miniature swine, with the assistance of an inflated anti-G suit, are able to compensate quite well to acceleration levels less than or equal to +7 GZ. Exposure to +9 GZ often resulted in unstable cardiovascular states involving relative bradycardia, often progressing to asystole, declining aortic blood pressure, and markedly diminished cardiac outputs approaching zero. It was found that, if aortic pressure and heart rate attain a relatively steady state during acceleration, and if heart level mean aortic pressure is greater than or equal to 100 Torr, the application of the microsphere technique during +GZ acceleration is theoretically valid. This hypothesis was tested using the microsphere technique (9.0 +/- 0.8 microns diam) in conscious miniature swine during exposure to +GZ acceleration. It is concluded that within the defined limits the radiolabeled microsphere technique is as accurate for use during acceleration studies as it is for use in routine laboratory studies.


Fibrinogenolysis and fibrinolysis with strenuous exercise. Twenty healthy young men were exercised on a treadmill according to the protocol of Balke and Ware. Mean duration of exercise was 24.9 +/- 5.7 min and mean maximum heart rate was 195 +/- 9. Fibrinolytic activity was markedly accelerated with euglobulin lysis times decreasing to 36% of control values and fibrinogen-fibrin degradation products increasing 109% after exercise. Assays for fibrin monomer were negative in all samples. In vivo fibrinogen A alpha-chin degradation was assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis of reduced samples of fibrin monomer isolated by clotting plasma samples in the presence of 0.1 M epsilon-aminocaproic acid and 1% disodium ethylenediaminetetraacetate. The A alpha-chain, the fibrinogen chain most susceptible to plasmin degeneration, showed no evidence of increased degeneration after exercise. Gel scans showed no decrease in the ratio of total alpha-chain to beta- and gamma-chains after exercise. The ratio of intact alpha 1 chain (alpha 1, 67,000 mol wt) to total alpha-chain was 0.66 +/- 0.13 before exercise, 0.64 +/- 0.14 immediately after exercise, and 0.65 +/- 0.13 1 h after exercise. The rate and extent of crosslinking of the alpha-chain of fibrin formed by clotting plasma samples was unaltered by exericse. These data suggest that physiologically significant fibrinogenolysis does not occur with strenuous exercise, even when fibrinolytic activity is markedly accelerated.


Effects of neuromuscular blockade on respiratory mechanics in conscious man. The effect of submaximal neuromuscular blockade (SMNB) on lung and chest wall mechanics was studied in six normal, awake subjects infused with pancuronium. Measurements of static lung volumes, specific airway conductance (sGaw), maximum expiratory and inspiratory flow-volume (MEFV, MIFV) curves, and static pressure-volume (PV) curves of the lung and of the relaxed chest wall were obtained after lung recoil pressure (Pst(L)) at full inflation had been reduced to 60 +/- 10% of control. Inspiratory capacity was decreased, but residual volume was not increased. Inspiratory PV curve of the lung was not modified, and the observed decrease in expiratory compliance and the slight increase in Pst(L) during deflation were compatible with the altered lung volume history. SMNB did not modify sGaw nor the relationship between Pst(L) and MEF; by contrast it markedly reduced MIF rates. Finally, SMNB transposed the chest wall PV curve to higher levels on the pressure axis (it decreased the outward pull of the chest wall) without greatly affecting its slope, and thereby it reduced the resting level of the respiratory system. We conclude that 1) muscle weakness per se does not affect the eleastic properties of the lungs and airways, and 2) involuntary respiratory muscle activity influences the elastic recoil of the chest wall. We believe this muscle activity originates from muscle spindles, and lies essentially in the inspiratory portion of the intercostal musculature.


Action potential correlates of pressure-induced changes in cardiac conduction. Microelectrode studies were undertaken to determine the cellular bases for hydrostatic pressure effects on impulse propagation and refractoriness in cardiac muscle. Canine Purkinje fibers, at 37 degrees C, were exposed to increases in hydrostatic pressure to 150 ATA. At 150 ATA membrane excitability was depressed and the maximum upstroke velocity (Vmax) of the action potential was reduced by 10%. Furthermore, the curve relating Vmax to takeoff potential (membrane responsiveness relation) shifted downward and to the right with the half inactivation voltage shifting in the hyperpolarizing direction by about 4 mV. Decreases in excitability and responsiveness occurred concomitantly with pressure-induced decreases in impulse conduction. Action potential duration (APD) increased significantly at 150 ATA. APD measured at -20 mV, -60 mV, and at maximum repolarization averaged 20.7, 15.5, and 13.5% longer than their respective 1-ATA values. The combined effects of increased APD and depressed responsiveness account for increased tissue refractoriness. The implications of the findings with regard to the arrhythmogenic nature of high hydrostatic pressure are discussed.


Ventilation in dogs on cardiopulmonary bypass with and without lungs. In 13 anesthetized or awake dogs, on cardiopulmonary bypass, we varied PaO2 and PaCO2 while continuously monitoring ventilatory responses and mechanics, to assess the dog's ability to maintain eupneic ventilation for any chemical drive. In a second group of 13 dogs on cardiopulmonary bypass we repeated the tests after removal of both lungs, to assess the importance of pulmonary feedback and mechanics. The VE/PO2 plot formed two hyperbolas, asymptotic to 39 Torr PO2 with lungs, and to 27 without; both intercepted zero ventilation near 200 Torr. Hyperoxic apnea occurred at, or below, PCO2 30 +/- 7 Torr under barbiturate and 20 +/- 4 Torr under morphine. Steady-state low PCO2 (10 Torr) turned off hypoxic drives as low as 20 Torr PO2. Empty-chest dogs had a low respiratory frequency (18 vs. 40), and near zero dynamic elastance; ventilatory work per minute and airway resistance were the same with and without lungs. Chest wall ventilatory responses are grossly independent of the presence of absence of lungs.


Reflex control of skin blood flow by skin temperature: role of core temperature. Two protocols were used to discover whether the reflex response in skin blood flow (SkBF) to rising skin temperature (Tsk) was dependent on the level of internal temperature. Part I. In five subjects, Tsk (controlled with water-perfused suits) was raised to 37 degrees C prior to, between 2 and 5 min, or between 10 and 17 min of exercise. The associated SkBF elevation per degree rise in Tsk averaged 0.20, 1.28, and 1.75 ml/100 ml . min, respectively. When Tsk was raised during the first 5 min of exercise, esophageal temperature (Tes) rose markedly (0.39 degrees C), but transiently fell if Tsk was raised after 10 min of exercise. Part II. In six subjects, different work loads were used to develop different levels of internal temperature. Tsk was elevated to 37 degrees C after 10--15 min at light (50--75 W) or moderate (100--150 W) work loads. At the heavier work load (and higher Tes), the rise in forearm SkBF per degree rise in Tsk averaged 2.33 +/- 0.38 (SE) times that observed at the light work load. These data strongly suggest that the reflex response of SkBF to rising Tsk is dependent on the level of internal temperature.


Influence of air velocity and heat acclimation on human skin wettedness and sweating efficiency. Before and after heat acclimation, four male resting subjects were exposed to humid heat that caused levels of skin wettedness ranging from 50 to 100%. The physical experimental conditions were chosen so that the same skin wettedness was attained with modification of only the ambient water vapor pressure, at two wind speeds (0.6 and 0.9 m . s-1). The esophageal temperature (Tes), mean skin temperature (Tsk), sweating rate (msw), and dripping sweat rate (mdr) were recorded; the amounts of local drippage in the same thermal conditions before and after acclimation were also determined. The relationship between the evaporative efficiency of sweating (eta sw) and the skin wettedness (w) is reported, as is the influence of the subject's acclimation to humid heat on adjustments of skin wettedness. The effects of the air velocity on the coefficient of evaporation and on sweating efficiency are discussed. Beneficial increases in evaporation were achievable by increasing skin wettedness only when there was a consistent drippage, which differed from one body area to another and from one subject to another. The relation of drift in body temperature to skin wettedness changed with the acclimation of the subjects.


Breathing frequency responses to pulmonary CO2 in an isolated lobe of the canine lung. Recent studies have indicated that the breathing frequency responses to inspired CO2 in part result from changes in pulmonary stretch receptor activity. Pulmonary CO2 may alter frequency by direct inhibition of stretch receptor discharge, or secondarily, by changes in airway mechanics. The vascularly isolated left lower lobe (LLL) of the canine lung was used to determine the effect of hypocapnic airway constriction on the pulmonary CO2 reflex. The upper and middle lobes of the left lung were removed and the right vagus nerve sectioned. Blood was recirculated through the LLL. Diaphragm electromyogram was used as an index of respiratory center activity and to trigger ventilation of the left lower lobe. Lobar hypocapnia increased peak airway pressure and reduced respiratory rate. However, infusion of isoproterenol or the use of a mechanical overflow system to block the airway pressure response prevented the frequency changes associated with CO2. Although both the direct and mechanical effects of CO2 on stretch receptors may contribute to the reflex, in the LLL preparation the mechanical effects predominate.


Plasma catecholamines and cardiovascular responses to cold and mental activity. Plasma epinephrine (E) and norepinephrine (NE) as well as blood pressure and heart rate variations were measured in 12 male subjects before, during, and after a cold hand test (5 degrees C for 2 min), a mental arithmetic test, and a combination of both these tests. Although the cold and mental tests had comparable effects on blood pressure, the heart rate response was greater than the mental test. The mental test produced a greater increase of E than the cold test, but the effect of the cold test was greater on NE than on E. Changes in heart rate were significantly correlated with E variations but not with NE, whereas changes in blood pressure were correlated with NE. Resting NE was correlated with resting blood pressure and resting E with resting heart rate. Finally the levels of basal E were positively correlated with the increase in E during the test. Cardiovascular changes were shown to be differently modified by a mental and a cold test. Evidence was given indicating that these changes are related to differences in E and NE responses in the presence of these tests.


Autonomic pathways responsible for bradycardia on facial immersion. The autonomic pathways mediating the bradycardia response to facial immersion (FI) have not been fully elaborated in man. By means of parasympathetic and sympathetic blockade we studied the heart rate response to FI in nine highly trained young swimmers, at rest and during dynamic cycle exercise. With no blockade, heart rate at rest declined with FI 36 +/- 18%. Under beta-blockade with propranolol or alpha-blockade with phentolamine FI produced a similar decrement. Atropine reduced the response. During exercise FI produced 48 +/- 9% decline without blockade. The response was similar with beta-blockade, but was completely abolished with atropine. Systolic blood pressure responses to FI measured by cuff in three subjects were small and bore no relation to the heart rate response. The results are compatible with parasympathetic efferent mediation of the heart rate response to FI. They are incompatible with a role for sympathetic mediation except as a complex interaction between parasympathetic and sympathetic influences. Hypertension and other sympathetic responses to FI do not play a role in production of bradycardia, but are apparently incidental effects. The heart rate decrement produced by FI increases with greater steady-state heart rate.


Maximal work capacity of women during acute hypoxia. Six healthy women (22--34 yr of age) performed maximal bicycle work in a hypobaric chamber at sea level and at simulated altitudes of 2,130 and 3,050 m (barometric pressures, 758, 586, and 523 Torr). Maximal oxygen uptake (VO2max) decreased 10 and 15% from sea-level values at 2,130 and 3,050 m, respectively. At these altitudes minute ventilation (VEBTPS) increased 17 and 22% respectively, a consequence of increased respiratory rate (fR). Respiratory exchange ratios increased 10 and 14%, and oxygen pulse decreased 9 and 12%, respectively, at 2,130 and 3,050 m. Maximal blood lactates, heart rates, cardiac outputs, and plasma volume shifts were unaffected by these altitudes. Although during maximal work the percentage increases in VEBTPS, fR, and R that resulted from altitude exposure were greater in women than those previously reported for men, the decrements in VO2max were comparable to those in men. The results show that relative to their performance at sea level, men and women have equal ability to perform maximal work at altitudes up to 3,050 m.


Measurement of pulmonary edema in intact dogs by transthoracic gamma-ray attenuation. We evaluated the attenuation of the 122 keV gamma ray of cobalt-57 across the thorax of anesthetized dogs as a method for following the time course of lung water changes in acute pulmonary edema induced by either increased microvascular permeability or increased microvascular hydrostatic pressure. The gamma rays traversed the thorax centered on the seventh rib laterally where the lung mass in the beam path was greatest. Calibration measurements in isolated lung lobes demonstrated the high sensitivity and inherent accuracy of the method over a wide range of lung water contents. In control dogs reproducibility averaged +/-3%. Increased permeability edema led to large rapid increases in the transthoracic gamma ray attenuation (TGA), while increased pressure caused an immediate, modest increase in TGA (vascular congestion) followed by a slow further increase over 2 h. There was a fairly good correlation between the increase in extravascular lung water and the change in TGA. The method is simple, safe, and noninvasive and appears to be useful for following the time course of lung water accumulation in generalized lung edema in anesthetized animals.


Effects of electrode position on esophageal diaphragmatic EMG in humans. The effects of electrode position and gastric-balloon anchoring on esophageal diaphragmatic EMG (EMGdi) responses to CO2 rebreathing were studied in seven normal sitting humans using an esophageal catheter that consisted of four platinum wire coils enabling simultaneous recording of three EMGdi signals from three different sites in the esophagus. A gastric balloon attached to the distal end of the catheter allowed anchoring of the catheter. EMGdi signals were quantitated as a moving time average. Two rebreathing experiments were performed with and without balloon anchoring on the same day. Changes in electrode position of at least 2 cm above the site of maximum EMGdi activity caused minimal changes in the moving average EMGdi and did not significantly effect the quantitated EMGdi response to CO2 rebreathing. The maximum EMGdi activity was approximately 2 cm above the gastroesophageal junction in sitting humans. Stabilization of the catheter with an inflated gastric balloon did not improve the reproducibility of the EMGdi data. Finally, the EMGdi response to two CO2 rebreathing runs done at the same sitting showed intraindividual reproducibility.


Middle ear gas exchange in isobaric counterdiffusion. Nitrous oxide entry into the middle ear gas space was studied in cats in relation to anesthesia and the vestibular dysfunction caused by isobaric inert gas counter-diffusion in diving. A catheter implanted in the auditory bulla was used for direct gas sampling and pressure measurements. Experiments were designed to evaluate the participation of the eustachian tube, mucosal blood vessels, and tympanic membrane in middle ear gas exchange. The eustachian tube did not contribute to N2O entry and the mucosal blood supply only contributed about one-third of the total N2O accumulation. Diffusion across the tympanic membrane accounted for most of the N2O entering the middle ear from ambient and respiratory environments containing N2O.


Hysteresis of contracted airway smooth muscle. How does smooth muscle tone affect the properties of airways during breathing maneuvers? We have studied the dynamic relationships of airway pressure and cross-sectional area in excised dog lobes and isolated tracheal segments during simulated breathing maneuvers. When contracted by carbachol, airways developed complex hysteretic behavior, becoming less compliant in small tidal breaths and rapid deflations, and grossly hysteretic in large tidal maneuvers. For a given sequence of maneuvers the patterns of hysteresis varied with timing. Analogous behavior was seen during length-cycling of dog trachealis muscle strips. The mechanisms suggested by the hysteretic patterns of muscle length-tensional plots are 1) slipping of contractile filaments at threshold forces during lengthening and 2) active shortening of contractile filaments that is slow relative to many respiratory events. The observed behavior indicates that measurements of pulmonary function that depend on airway caliber or stiffness should become increasingly affected by the sequence, amplitude, and timing of breathing maneuvers as smooth muscle tone increases. The stiffness for small amplitude cycling may be favorable for local control of ventilation by parenchymal smooth muscle.


Stochastic description of inert gas exchange. Data from experiments measuring the rate of uptake and elimination of nonmetabolic gas in living organs are usually analyzed by several exponential time constants or their equivalent half-times (i.e, exponential series analysis). To avoid the limitations of this technique, we have formulated a method that combines analysis by moments of distribution with transfer function techniques, which makes the analysis independent of any mechanistic model. This method is an improvement over previous methods because it allows better comparison of gas exchange experiments and better prediction of gas exchange in the formulation of diver decompression schedules. Measurements of radioxenon uptake and elimination in two areas of a dog are presented. Analysis of the same organ response by both methods showed a fivefold variation in derived exponential time constants compared with less than 10% variation among moment descriptors.


Maximum oxygen consumption of rats and its changes with various experimental procedures. A ten-stage treadmill test was developed and standardized to secure the VO2max of male and female rats assigned to various cross-sectional and longitudinal experimental groups. Repeated measurements indicated that the test procedure was reliable and could be used for research purposes. When the test was used with different strains, the untrained Sprague-Dawley rats had significantly higher VO2max values than animals of the Wistar-Kyoto (WKY) or the Okamoto-Aoki (SHR) strains. Exercise schedules were evaluated that were similar to those previously used by various investigators and it was found that most were exercising their rats at levels exceeding 75% VO2max. After 6--10 wk of chronic exercise, significant increases in VO2max occurred that ranged between 12 and 26%. Longitudinal studies (1 yr) with hypertensive (SHR) rats revealed that it was more desirable to logarithmically evaluate the relationship between VO2max and body mass than by the conventional method of ml . kg-1 . min-1. When this approach was used with SHR animals, the VO2max differences between the sexes were not apparent until the animals were 1 yr of age. On the other hand, training by male SHR rats caused significant increases in VO2max regardless of the method used to express the results. It is recommended that future studies designed to elucidate exercise mechanisms in rats should include a standardized VO2max test.


Effects of graded reduction of brain blood flow on chemical control of breathing. We measured ventilatory responses to CO2 (delta VI/delta PCO2) and transient hypoxia (delta VI/delta SaO2) during reductions of brain blood flow (BBF) to 70% and 50% of control in unanesthetized goats. Increase in inspiratory volume per change in CO2 tension (delta VI/delta PCO2) was measured during rebreathing with sampling of both arterial and cerebral venous blood; increase in inspiratory volume per fall in arterial oxygen saturation (delta VI/delta SaO2) was assessed by the transient N2 inhalation method. Delta VI/delta SaO2 did not significantly change at 70% BBF, but was depressed at 50% BBF. Delta VI/delta PCO2 increased (0.94 +/- 0.18 to 1.29 +/- 0.24 l . min-1 . Torr-1) at 70% BBF if arterial CO2 tension were used to represent the CO2 stimulus but was unchanged if venous CO2 tension were used. At 50% BBF, delta VI/delta PCO2 was depressed (0.38 +/- 0.13 l . min-1 . Torr-1) for both representations of the CO2 stimulus. Brain ischemia increased blood pressure and heart rate but blunted the increase in BBF caused by hypercapnia. We conclude that 1) moderate brain ischemia (70% BBF) does not affect chemosensitivity to hypoxia and CO2, 2) delta VI/delta PCO2 may not be accurately determined from PaCO2 during brain ischemia because cerebrovascular reactivity to CO2 is depressed, and 3) severe brain ischemia (50% BBF) blunts delta VI/delta SaO2 and delta VI/delta PCO2, probably as a consequence of hypoxic depression of the respiratory neurons.


Left ventricular hemodynamics during respiration. We have investigated the mechanisms involved in the inspiratory fall in left ventricular stroke volume (LVSV), utilizing a spontaneously breathing dog on right-heart bypass (RHBP). We have been able to control lung volume, pulmonary artery inflow, and right-heart volume (RHV). During Mueller maneuvers in one series, RHV was allowed to increase as pleural pressure (Ppl) fell; in a second series, changes in RHV were excluded. In both series LVSV fell significantly, associated with a significant rise in the transmural (relative to Ppl) aortic diastolic pressure, reflecting an increase in the effective LV afterload. The transmural left ventricular filling pressure did not fall, a fact inconsistent with decreased pulmonary venous return, causing the fall in LVSV. The LVSV fell significantly more when RHV was allowed to increase as when it was held constant with all other variables showing no statistical change. Thus, increases in both RHV and effective LV afterload are created by the inspiratory fall in Ppl and summate to decrease LVSV.


Disappearance of norepinephrine from the circulation following strenuous exercise. Five subjects who had been training vigorously for 2 mo worked 5 min on the cycle ergometer at 1,480 +/- 100 kpm/min and at 1,920 kpm/min on separate days. Plasma norepinephrine (NE), blood lactate, and heart rate were determined during the postexercise periods. The same subjects were also tested at 1,480 +/- 100 kpm/min after a 2-mo detraining period, when subjects did not train. At 1,920 +/- 80 kpm/min, plasma NE was 4 ng/ml at the end of exercise. The NE concentration increased slightly in the first min postexercise, then decreased with a half-time of 2.8 min between 1 and 11 min postexercise. Detraining for 2 mo did not markedly affect the rate of disappearance of NE in the postexercise period in these five subjects. Between 11 and 30 min postexercise (1,480 +/- 100 kpm/min), heart rate was 25 beats/min higher after detraining, while NE was not significantly different. These data provide evidence that more rapid recovery of heart rate in trained individuals during this period is not likely due to a more rapid recovery from the sympathetic response to exercise.