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Biomedical subjects

K Rai

Publications and source records attributed to K Rai.

54 records · Page 3Linked to original sources

Compartmental body composition of cancer patients by measurement of total body nitrogen, potassium, and water.

Quantitative measurement was made of body composition in patients with several forms of neoplastic disease. Total body nitrogen was determined by means of the prompt gamma neutron activation technique; total body potassium was measured with the use of a whole body counter. The mass and protein content of the muscle compartment and nonmuscle lean tissue were estimated by application of the technique of compartmental analysis. Total body water, determined simultaneously with the use of tritium label, provided a measure of lean body mass. From these data, the body fat can be inferred. The prompt gamma neutron activation and whole body counting techniques represent a considerable advance over the balance and radioisotope techniques used in earlier studies. The new techniques make possible sequential studies over prolonged periods of time with a considerable degree of accuracy. The loss of body weight by patients with solid tumors consisted primarily of the loss of muscle mass and body fat. Even in severe wasting, the patients appear to retain significant amounts of body fat. It is the skeletal muscle which is predominantly lost; the visceral life-supporting system is, to a considerable extent, spared. The nonmuscle tissue including the visceral fraction did not change in this study, and actually appeared to increase in size when comparison was made with the normal contrast population. The loss of total body water was slight in the cancer patients studied.

Adipose Tissue↗

A generalized multihit dose-response model for low-dose extrapolation.

A quantal dose-response model based on a multihit theory of toxic response is presented. When spontaneous background toxic response is included, the model involves three unknown parameters. The maximum likelihood estimators for these three parameters are given as the solution of a nonlinear iterative algorithm. The resulting three-dimensional vector of estimators is shown to be asymptotically strongly consistent, asymptotically unique with probability one, and, when suitably normalized, it has asymptotically a trivariate normal distribution. On the basis of these results, a large-sample goodness-of-fit test is given. The use of this model for low-dose extrapolation is indicated. Application of the results is illustrated using three sets of toxicity data.

Animals↗

T cell helper defect in patients with chronic lymphocytic leukemia.

Purified peripheral blood T lymphocytes from normal donors were shown to help allogeneic tonsillar B cells to differentiate and secrete specific anti-SRBC antibody in vitro in a plaque-forming assay. Utilizing this system, a comparison was made between the allogeneic helper activity generated by the T cells of normal individuals and patients with various disease states. Allogeneic helper activity was absent when T lymphocytes from patients with CLL were used. Conversely, relatively normal allogeneic helper function was provided by T cells of patients with a variety of other disorders studied. Thus, a functional deficiency was identified in CLL patients in the subpopulation of regulatory T cells responsible for providing helper activity in allogeneic interactions.

B-Lymphocytes↗

Guidelines for protocol studies in chronic lymphocytic leukemia.

The treatment of any malignant disease requires appropriate criteria for diagnosis of the disease, appropriate methods for study, and techniques for evaluating response to treatment. In the past five years, there have been a number of proposed guidelines for studies in chronic lymphocytic leukemia (CLL). These submitted guidelines represent a further re-evaluation of concepts in CLL, and are currently in use by Cancer and Leukemia Group B for protocol studies. It is clear that revisions will continue to be make as new knowledge accumulates. In the meantime, these are submitted for publication for use by other investigators.

Drug Therapy↗

Effect of positive acceleration (+gz) on electrocardiogram of subjects with vasoregulatory abnormality.

ST-T wave changes in the electrocardiogram detected during routine examination and aggravated by erect posture, hyperventilation, and exercise in apparently healthy young individuals have been termed vasoregulatory abnormalities. No evidence of ischaemic heart disease has been found in such subjects. Ten young healthy air crew with vasoregulatory abnormalities were subjected to maximal exercise on treadmill and procedure repeated after 120 mg propranolol daily for 3 days. After one week, they were subjected to a stress of positive acceleration (+gz) in a human centrifuge at 2-5 g and 3-5 g for 15 seconds each at a constant rate of rise of 0-1 g/s and the electrocardiogram was monitored during and in the post-acceleration phase. The procedure was repeated after propranolol 120 mg daily for 3 days. The stress of positive acceleration resulted in pronounced prominence of P waves and inversion of T waves (as has been reported in normal subjects) with minimal ST depression in the electrocardiogram. ST segment depression during exercise, at heart rates corresponding to those achieved during peak centrifuge runs, was significantly more pronounced. The ST, P, and T wave changes were returned to normal after propranolol. It is concluded that minimal ST segment depression after stress of positive acceleration as compared with conspicuous ST segment depression during exercise at corresponding heart rates, and their normalisation after propranolol, rules out ischaemia as an aetiological factor in subjects with vasoregulatory abnormalities.

Acceleration↗

The self-inflicted wrist slash.

Twenty-nine patients with self-inflicted wrist slash seen in consultation from 1970 through 1974 revealed 25 nerve and 70 tendon injuries. The average age, sex distribution, and psychiatric status generally followed previously reported series of suicide attempts. A major finding was the low patient response to surgical and psychiatric followup. Intensified efforts to improve followup and primary repair of damaged structures are recommended.

Adolescent↗

Vitamin A assay in burned patients.

A study of serum vitamin A levels in burned patients at the Vancouver General Hospital (1972-1973) is reported in an attempt to relate hypovitaminosis A to acute stress erosions in the gastrointestinal tract. Thirty-one patients were studied, of whom 10 had moderate to severe burns. Vitamin A levels of normal males and females at the Vancouver General Hospital averaged at 35 mug/100 ml. Patients with burn indices of less than 12 did not show any significant fall in serum vitamin A levels. The fall of vitamin A levels was greater as the burn index increased, and the fall of vitamin A level was noticed within 48 hours postburn and returned to normal by the second week postburn. In patients with severe burns and gastrointestinal bleeding with stress ulcers, the serum vitamin A levels fell more profoundly (e.g., 18 mug/100 ml). Four patients with gastrointestinal bleeding were detected, of whom three had acute gastric erosions with low serum vitamin A levels. The possibility that hypovitaminosis A is a contributing factor in acute gastric erosions of the gastric mucosa in severely burned patients is suggested.

Adolescent↗

Treatment of early chronic lymphocytic leukemia: intermittent chlorambucil versus observation.

The effect of early therapy on the course of chronic lymphocytic leukemia (CLL) has not been established. Fifty-nine patients with indolent Rai stage I and II CLL were randomized to receive intermittent chlorambucil once a month or to receive no treatment. The two groups were comparable in entry characteristics. At 5 years from randomization there was no significant difference in survival between the two groups although the proportion of patients exhibiting active disease 5 years after randomization is 70 per cent in the untreated group and 55 per cent in the treated group. In this study, early treatment of CLL with intermittent chlorambucil did not result in a survival advantage for patients with indolent stage I and II CLL.

Aged↗

Dermatoglyphic peculiarities in children with oral clefts.

In humans, the development of the primary palate and the lip is completed by the 7th week of intra uterine life and that of secondary palate by 12th week. The dermal ridges develop in relation to the volar pads, which are formed by the 6th week of gestation and reach maximum size between 12th and 13th weeks. This means that the genetic message contained in the genome--normal or abnormal is deciphered during this period and is also reflected by dermatoglyphics. Hence this study was done in order to observe the differences in dermatoglyphic patterns between the children with oral clefts and normal children and to determine the usefulness of dermatoglyphics in studying the genetic etiology of oral clefts. Dermatoglyphic data from 50 oral cleft children and 50 normal children were collected using the ink method and comparison was done between them. In the present study, we found an increase in the ulnar loop patterns on the distal phalanges of the ten fingers, an increase in the atd angle and an increase in the fluctuating asymmetry of the atd angle in the oral cleft children which indicates the degree of developmental instability of the oral cleft individual.

Adolescent↗