Experimental toxemia in the pregnant primate

In order to develop a model for the study of eclamptogenic toxemia, a series of experiments were carried out on 31 female baboons. In Group 1, consisting of 10 animals, metal clips were placed around the uterine arteries in order to partially occlude them, and the ovarian vessels were transected. The animals were subsequently mated. Nine developed hypertension and proteinuria, and one aborted. The renal lesions in these animals were indistinguishable from those described in human toxemia. Group 2 consisted of three of the 10 baboons from Group 1, which became pregnant a second time. They again developed hypertension and proteinuria. In Group 3, three baboons at 100 days of gestation were treated as in Group 1 with similar results. Groups 4 and 5 served as pregnant (3) and nonpregnant (15) controls. It is concluded that a toxemia model has been developed in a subhuman primate. This model will prove useful in the further study of eclamptogenic toxemia.

Fatty acids of cerebrosides in different regions of the developing foetal brain

The fatty acid composition of cerebrosides of developing foetal human brain and regional variations, if any, during intrauterine life were studied. While palmitic and stearic acids were the predominant normal fatty acids throughout intrauterine life, long chain fatty acids, like lignoceric and nervonic acids, which were low at early gestational ages, rapidly accumulated at term. Regional differences were observed in the concentrations of long chain normal fatty acids especially at term. Medulla oblongata showed a greater accumulation of long chain fatty acids as compared to the cerebellum and cerebrum. The distribution of 2-hydroxy fatty acids in different regions showed a pattern predominantly that of long chain carbon units, even at 34 wk of foetal life. A higher ratio of lignoeric to stearic acid in the case of normal fatty acids, probably indicative of chain elongation, was also evident in the case of medulla oblongata and cerebellum as compared to the cerebrum. The significance of these qualitative alterations in relation to rapid growth of brain prior to term and the process of myelination has been discussed.

Haematological profile in leprosy. Part I--general findings

Haematological studies in 904 adult leprosy patients with different types of leprosy, in various stages of the disease and treatment are described. Haemoglobin, packed cell volume, serum albumin and serum iron are significantly lower among lepromatous leprosy patients as compared with non-lepromatous patients. The serum B12 levels were significantly higher among the lepromatous group. Acid fast bacilli have been demonstrated in skin smear negative leprosy patients with indeterminate and tuberculoid leprosy, suggesting occurrence of bacillaemia in these groups of patients.

Natural history of the ventricular septal defect in tricuspid atresia and its surgical implications

We have previously reported isolated cases of anatomical and functional closure of ventricular septal defects in tricuspid atresia. To study this phenomenon further, clinical, angiographic, and pathological findings in 20 consecutive cases of tricuspid atresia were reviewed. Sixteen cases were found to have normally related great arteries (type I) and 4 had transposition (type II). In 6 of these patients there was evidence of closure of a ventricular septal defect; in 3 this was complete and in the other 3, partial. Five of these ventricular septal defect closures occurred in type I patients and one among type II. Increasing cyanosis and polycythaemia and/or disappearance of a previously heard murmur were observed in all patients; these signs are more conspicuous in complete closure than in partial. The incidence of closure of ventricular septal defect in tricuspid atresia is 38 per cent and approximates to the incidence of spontaneous closure of isolated ventricular septal defects. Progressive muscular "encroachment" of the margins of ventricular septal defects with subsequent fibrosis and covering by endocardial proliferation is the most likely mechanism of closure in tricuspid atresia. The factors initiating the closure of ventricular septal defect remain unknown, but because of its occurrence in patients both with and without previous shunt operations, it is reasonable to assume that closure of ventricular septal defect in tricuspid atresia is not initiated or accelerated by these surgical shunts. Recent developments in surgical technique permit total surgical correction of tricuspid atresia at least in a physiological sense, but these operations can be successfully performed only in older children (over 8 years). Thus, palliation is essential in younger patients until they reach the age for total correction. A Blalock-Taussig shunt is recommended in preference to a Glenn anastomosis because the latter may leave the left pulmonary circuit without blood supply if the ventricular septal defect closes. In type II cases, a large and non-restrictive ventricular septal defect is essential for survival of the patient after the Fontan operation. For this reason, the size of the ventricular septal defect should be evaluated before and at the time of surgical correction. If the ventricular septal defect is small in a type II case, resection of the ventricular septum or a complete bypass of the ventricular septal defect and right ventricle is necessary at the time of the Fontan operation.

Effect of propranolol on the relationship between atrial systolic pressure and type A atrial receptor discharge in cats

The responses of type A atrial receptors to graded infusions of saline and large doses of propranolol were examined in anesthetized cats. Infusion of saline raised the mean atrial pressure, but usually the amplitude of the atrial a wave was reduced. In general the receptor discharge was unaffected. Propranolol reduced the discharge from the control level when it was injected in doses no less than 4 mg/kg. Infusions of saline after propranolol resulted in an increase in the discharge and the increase was related to the amplitude and/or initial pressure of the a wave. In one case the discharge after propranolol was less than that when the atrium was widely slit open. It is concluded that at least part of the effect of the drug is due to a direct depression of the receptor rendering it less sensitive to the stretch provided by atrial contraction. The demonstration of a stimulus-response relationship between the a wave and the receptor discharge at low levels of activity suggests that under normal conditiions the receptor operates on a plateau of maximum activity, thus making a response to small changes in stimulus strength obscure.

An analysis of the value of additional diagnostic procedures

When several diagnostic procedures are performed on a patient, the probability of his having or not having a specific ailment will change as the result of each procedure is known. This paper describes how such a change is readily calculated using Bayes' theorem. Information theory is also used to find the increment in information from each successive test. Numerical estimates are made using data pertinent to lung X-ray examinations. Finally, some implications for diagnostic examinations in general are drawn.

Right ventricular growth in a case of pulmonic stenosis with intact ventricular septum and hypoplastic right ventricle

Adequate growth of the hypoplastic right ventricle in a patient with severe pulmonary stenosis with an intact ventricular septum was documented after pulmonary valvotomy in infancy. It is postulated that the growth of the ventricular chamber is largely the result of pulmonary regurgitation resulting from successful pulmonary valvotomy. Based on this and the observations of others on the growth of the hypoplastic right ventricle in pulmonary atresia (with intact septum) cases, an organized approach to eventual total surgical correction is recommended.

New manual and automated method for determining activity of creatine kinase isoenzyme MB, by use of dithiothreitol: clinical applications

The method is based on the selective activating capacity of dithiothreitol on creatine kinase isoenzyme MB, after isoenzyme MM is activated by glutathione. Isolated isoenzymes MM and MB of human and canine origin were assayed individually and in mixtures of known activities. When glutathione was present in the assay medium the activity of each isoenzyme could be measured individually, but glutathione did not activate isoenzyme MB if it was present in a mixture with MM. Dithiothreitol, added to the serum before assay, activated the isoenzyme MB in the mixture. Values for MB activities obtained for isolated isoenzyme MB and for the isoenzyme mixture after dithiothreitol was added averaged 110 and 111 U/liter, respectively (r = 0.998; y = 1.007 x + 0.298; n = 10). In the serum of 40 patients with documented acute transmural myocardial infarction, the mean proportion of isoenzyme MB activity measured in this way was 5.5% (coefficient of variation, 7.7%). Isoenzyme MB activities measured by use of dithiothreitol compared well with those obtained by conventional electrophoresis/spectrophotometry (r = 0.998; y = 1.09x -0.65) and spectrofluorometry (r = 0.996; y = 1.10 x + 0.80). The assay of MB activity by the dithiothreitol method was automated, by use of an Abbott Bichromatic Analyser and a Calbiochem Super-Stat Pack Kit. In 60 isoenzyme MB determinations the manual and automated method correlated well (r = 0.990; y = 1.0x -1.36). The simplicity of isoenzyme MB determination by use of dithiothreitol and its ease of automation allow routine monitoring of the isoenzyme activity in patients with ischemic heart disease.

Primary prevention of atherosclerosis: a challenge to the physician caring for children

This review article stresses the importance of prevention in the reduction of the incidence of artherosclerotic disease, especially coronary heart disease. Evidence accumulated from autopsy studies, animal experimentation, and long-term epidemiologic studies supports the concept that atherosclerosis has its inception in childhood. Adult programs designed to change life styles and attitudes or reverse morphologic changes appear doomed to failure. Therefore, if nutritional, physical activity, and smoking habits are to be altered, it is essential to begin these efforts in infancy and childhood.

Norlestrin-induced pseudopregnancy in the baboon. Effects on blood coagulation and endocrine glands during attempted production of Sheehan's syndrome

Production of Sheehan's syndrome was attempted. As it was not possible to obtain pregnant baboons initially, pseudopregnancy was induced with norlestrin, 2.k mg., for 3 and 4 months, respectively. Sheehan's syndrome was not produced with massive hypovolemic shock but failure to obtain true pregnancy has given serendipitous information on the long-term action of norlestrin on the pituitary and its target organs. Unusual abundance of prolactin acidophils and decrease of growth hormone acidophils was found. Further studies will be necessary to show the possible significance of these findings. As fibrin degradation products did not appear in the serum, we can make no inference about the necessity of intravascular coagulation for the production of Sheehan's phenomenon. Finally one animal became pregnant. Sheehan's phenomenon was not produced in her despite induction of intrapartum hypovolemic shock. Histologic findings in her pituitary resemble those of the pseudopregnant animals.

Transmission of leprosy within households

As part of the leprosy control program, population follow-up studies were carried out during 1962 to 1970 in Gudiyatham Taluk, an administrative unit in South India (population: 400,000). More than 97% of the 23,285 contacts from 5,088 families having a leprosy patient were clinically examined using accepted methodology and confirmed as having or not having leprosy. New cases developing among household contacts of leprosy (secondary attack rates) were determined and studied in relation to characteristics of the index case and that of contacts. The secondary attack rate is defined as the number of new cases discovered in the contacts of leprosy patients per 1,000 person-years, which is equivalent to observing 1,000 persons per year. Nearly two-thirds of all new cases were of the tuberculoid type of leprosy and another one-sixth of indeterminate type. Lepromatous and borderline cases each constituted about ten percent of the total new cases. The total secondary attack rate was 6.8 per 1,000 person-years. Compared to an annual incidence rate of 0.8 per 1,000 in the total population, this incidence rate among the contacts is nearly ten times higher. Such enhanced risks are observed clearly and consistently when studied by the number of patients within a family for both sexes and in various age-groups. The rate for females (6.3 per 1,000 person-year) though less, was not significantly different from that of males (7.1 per 1,000 person-year). The differences observed between males and females for each type of leprosy were also not statistically significant. The risks for children (less than 15 years) are significantly higher than those for adults. Among boys, the maximum risk was observed in the age-group 5-14 years, whereas for females the risk is highest in the age-group 5-9 years, dropping down significantly after that. Furthermore, it was observed that significant differences existed between children and adults only in males but not in females. The secondary attack rates almost doubled when there were multiple index cases in the family. Regardless of the number of index cases, the male-female differences were not statistically significant. Attack rates were significantly enhanced when there was a bacilliferous type of leprosy (lepromatous or borderline) in the family. This was true for the specific attack rates of each type of leprosy too. However, a significantly higher proportion of lepromatous and borderline types is also seen when there is a bacilliferous type of leprosy present. The study reiterates the differences in susceptibility to leprosy among males and females, especially during younger ages. Further immunological studies are necessary to determine the differences in host responses in males and females that produce such a characteristic sex-ratio in prevalence of leprosy. There is still a great need to obtain more data on incidence rates both in general population and among contacts on the basis of prospective observation using acceptable statistical technics in design and analysis.

Superior vena caval obstruction in total anomalous pulmonary venous connexion

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