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Biomedical subjects

R Viswanathan

Publications and source records attributed to R Viswanathan.

At least 55 records · Page 3Linked to original sources
PubMed1986

Assessment of the persistence of hexachlorobenzene in the ecosphere.

Various degradation tests were carried out to assess the persistence of hexachlorobenzene (HCB) in the ecosphere. HCB was irradiated with light of various wave-lengths in organic solvents and in water, partly after addition of H2O2 or metal oxides. Photolysis to various dehalogenated products occurred at different rates, depending on concentration and irradiation time; HCB adsorbed on a silica gel was mineralized by light to CO2. A negligible amount of 14C-labelled HCB was mineralized to 14CO2 in various biodegradation tests. In an outdoor lysimeter experiment, 14C residues were found in all parts of wheat plants grown from seeds treated with 14C-HCB. Besides the parent compound and bound residues in plants and soil, very small amounts of soluble polar metabolites were present in the plants; the main product of this group, isolated from roots, was conjugated pentachlorothiophenol. Wheat grown in soil with 14C-HCB residues contained unchanged HCB and bound residues.

Biodegradation, Environmental↗
PubMed1986

Physicians' and the public's attitudes on communication about death.

We studied the preferences of physicians and the public as to how physicians should inform a family of a patient's unexpected death. When the family had to be reached by telephone, 72% of our 150 physician-respondents preferred telling the family that the patient was critically ill and asking the family to come to the hospital immediately (critical notification [CN]); 25% of the physicians preferred announcing the death over the telephone (death notification [DN]). When the news had to be announced in person, 58% of physicians preferred immediately announcing it (IA), and 33% preferred gradual announcement (GA). A Gallup poll commissioned by us showed that 64% of the adult population in the United States preferred CN, 26% DN, 79% IA, and 17% GA; CN and IA were preferred in all the demographic subgroups examined. We discuss our findings, the reasons for them, and their ethical and practical implications.

Adult↗
PubMed1984

The experience of myocardial infarction as a threat to one's personal adequacy.

This report of a clinical case conference on a 40-year old man with acute myocardial infarction is presented in a format that readers of this journal may find useful in their teaching of health professionals and students. The report illustrates some psychologic aspects of myocardial infarction and the impact it had on this particular patient. In this case, the myocardial infarction reactivated some underlying unresolved conflicts about personal adequacy that the patient had previously kept under check by some fragile defense mechanisms. Thus, it disrupted the personality organization and produced emotional upheaval and maladaptive behavior. This in turn was deleterious to the patient's physical health. This case, therefore, illustrates the importance of the biopsychosocial approach in the understanding and treatment of medical illness.

Adaptation, Psychological↗
PubMed1983

Fate of chemicals in plant-soil systems: comparison of laboratory test data with results of open air long-term experiments.

Three laboratory short-term test systems were used to determine volatilization rates, mineralization rates, and conversion rates of 14 14C-labeled chemicals in soils or soil-plant systems. The chemicals covered a wide range of water solubility, vapor pressure, chemical stability, and biodegradability. In order to compare the data obtained with the environmental behavior of the respective chemicals, data from an outdoor experimental setup which had been shown to give residue data within the range limits of field conditions were used. Volatilization rates, mineralization rates, and conversion rates obtained in the laboratory were correlated to those found under outdoor conditions. Based on these correlations, predictions of field residues were made. The predicted values for total field residues were comparable to those found experimentally with the exception of two chemicals. The prediction of residues of unchanged parent compounds in the field was less satisfactory. The reasons for differences observed are discussed.

Environmental Pollutants↗
PubMed1982

Clopenthixol decanoate in the treatment of chronic schizophrenic in-patients.

Nineteen chronic schizophrenic in-patients were entered into a 12-week open study of intramuscular clopenthixol decanoate. Fourteen patients completed the full 12-week treatment period; 3 were withdrawn due to inadequate clinical response or untoward adverse effects, and 2 were discharged and lost to follow-up. Doses administered were in the range 200 to 400 mg, weekly or fortnightly. Patients were assessed weekly using the Brief Psychiatric Rating Scale (BPRS). Nurses' Observation Scale for In-patient Evaluation (NOSIE-30) and the Clinical Global Impression (CGI). Unwanted effects were recorded on a checklist. Statistically significant improvements in the overall mean scores were noted on the BPRS at every assessment and on the NOSIE-30 at every assessment except in Week 4. Unwanted effects were generally mild and they decreased during the study. The results suggest that clopenthixol decanoate is an effective, well-tolerated antipsychotic agent, suitable for the treatment of chronic, long-stay schizophrenic in-patients.

Adult↗
PubMed1979

Effect of furosemide on altitude tolerance in experimental animals.

Furosemide which is claimed to prevent acute mountain sickness and pulmonary oedema of high altitude was tried in experimental animals to evaluate its usefulness or otherwise as a measure of prophylaxis. 90 mice, 128 rats and 44 guinea pigs--all males--were used for the studies. Half the number in each species were kept as controls. The remaining half were further divided into two batches. The first batch was given furosemide 10 mg/kg body weight. Two h later they were exposed to simulated altitude of 30,000 ft for 6 h. The second batch was given two injections of furosemide at intervals of 24 h before exposure to simulated altitude. The controls were given distilled water. Our results show that the death rate was more in the furosemide-treated groups, both under mild as well as severe dehydration in all species. The present study does not substantiate the claim than the drug can be used as prophylactic against acute mountain sickness and pulmonary oedema of high altitude.

Acclimatization↗
PubMed1979

Effect of hypoxia on regional lung perfusion, by scanning.

Lung scanning was performed in 12 subjects who had pulmonary oedema of high altitude (POHA) before, and in 8 men who had been at high altitude without developing pulmonary oedema. Scanning done before and after 5 min 10% O2 breathing showed (a) increased perfusion in POHA subjects after hypoxia, (b) more in the lower than in upper zones, and (c) striking increase in perfusion in localised areas. In controls, however, there was significant reduction in perfusion after hypoxia in most areas. The reduction was less marked in the lower zones than in the upper zones. POHA subjects were hyperreactors to hypoxia, compared to controls. It is concluded that scanning before and after hypoxic breathing might help in differentiating hyperreactors.

Humans↗
PubMed1978

Allergic bronchopulmonary aspergillosis.

Allergic bronchopulmonary aspergillosis (ABPA) is not a common condition, even though asthma due to sensitization to Aspergillus antigen is very common in many countries because of the ubiquitous distribution of the fungus itself. During the course of 14 years, the Mycology Department of the V. P. Chest Institute, Delhi, has confirmed the diagnosis of ABPA in 46 patients. The present study is based on the follow-up of 17 patients for understanding the evolution of the disease. All of them had Aspergillus fumigatus (AF) in the sputum with positive type I and type III skin reaction to AF antigen. 7 patients were treated for 10 days with oral administration of Hamycin, an antibiotic isolated from one of the streptomycete species. Immediate results were very good, with marked alleviation of subjective symptoms and absence of fungi in the sputum. The drug deserves further trial.

Adult↗