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Biomedical subjects

R Nair

Publications and source records attributed to R Nair.

At least 91 records · Page 5Linked to original sources
PubMed1994

Malignant germ cell tumors in childhood.

The outlook for patients with germ cell tumors was poor before the advent of effective chemotherapy. In this study the outcome of multiagent chemotherapy in children treated for germ cell tumor is assessed. Between January 1984 and December 1990, 107 patients were diagnosed to have germ cell tumors. Postsurgical therapy was based on tumor site, stage, and histology. Combination chemotherapy was employed in patients with Stages I and II disease with postoperative raised tumor markers and all patients with Stages III and IV. Between 1984-1988, patients received cisplatin, vinblastin, bleomycin, and methotrexate (PVB-M), and thereafter between 1988-1990, they received bleomycin, etoposide, and cisplatin (BEP). Of 34 patients treated with PVB-M and 27 treated with BEP, the complete remission rate was 40% and 85%, respectively, and the overall survival was 30% at 5 years for PVB-M and 80% at 3 years for BEP. We conclude that etoposide with cisplatin is superior to vinblastin with cisplatin in the treatment of advanced germ cell tumors because of greater efficacy, decreased toxicity, and better compliance in children.

Adolescent↗
PubMed1994

Individual differences in the macronutrient preference profile of outbred rats: implications for nutritional, metabolic, and pharmacologic studies.

While screening outbred male Holtzman Sprague-Dawley rats for their macronutrient (protein, carbohydrate, and fat) preferences, we noticed substantial group-to-group variation in the preference profile. This led us to analyze preference data on two hundred and seventy rats collected over a three-year period to determine whether preferences could be predicted. The results led us to conclude that observed variations in macronutrient preference profiles may be secondary to genetic heterogeneity in the outbred population. We have also shown that the outcome of the pharmacologic effects of two agents (insulin and enterostatin) on appetitive behavior will vary from animal to animal within a single group. Accordingly, researchers must be aware that the breeding history of the laboratory animal is a major factor in the outcome of the experiment and interpretation of the findings.

Animal Nutritional Physiological Phenomena↗
PubMed1994

Modified MACOP-B chemotherapy for intermediate and high grade non Hodgkins lymphomas.

Combination chemotherapy consisting of methotrexate with leucovorin rescue, doxorubicin, cyclophosphamide, vincristine, prednisolone and bleomycin (MACOP-B) has been extensively used for the treatment of Non Hodgkins Lymphoma. However, different results have been reported. The aim of this study was to assess the feasibility of administration of this regimen on an out patient basis and to confirm the efficacy of MACOP-B. 51 patients with intermediate--and high--grade lymphoma were treated with this regimen in a single institute study. Numerous clinical features predictive of response and disease free survival were analysed. The Median age was 48 years (range 14-77). Diffuse large cell lymphoma was seen in 65%, diffuse small cleaved in 10% and diffuse mixed in 15%. Eight patients (15%) had Stage I disease, 18 (35%) Stage II, 12 (23%) Stage III and 13 (25%) Stage IV. Complete remission was achieved in 65% of the patients. With a median follow up of 18 months, 40% of the patients are alive at 40 months. Sixty percent of the complete responders are disease free at 40 months. Response rates did not differ significantly for age, sex, stage, histology, bone marrow involvement and extranodal disease. However patients with absence of B' symptoms, non bulky disease at presentation and diffuse large cell histology had a higher percentage of complete remission. Hematological toxicity occurred in 90% and was grade IV in 14% patients. Three patients died of sepsis. Severe mucositis occurred in 40% of the patients. In conclusion, while it is possible to give aggressive chemotherapy at the out patient basis in India we failed to confirm the high response rates as originally reported.

Adolescent↗
PubMed1994

Laparoscopic cholecystectomy in England and Wales: results of an audit by the Royal College of Surgeons of England.

The results of an audit of open and laparoscopic cholecystectomy conducted by the Comparative Audit Service of The Royal College of Surgeons of England are presented. Data were submitted by 124 consultant surgeons on 3319 attempted laparoscopic and by 227 consultant surgeons on 8035 open cholecystectomies performed in England and Wales during the 2 years 1990 and 1991. These were contrasted with 9322 attempted laparoscopic cholecystectomies reported in 21 series reported in the world literature between 1991 and 1992, and with five other nations' audit studies. Among attempted laparoscopic cases, conversion to an open procedure was necessary in 175/3319 (5.2%) of cases and overall mortality was 0.15% (5/3319). Major complications were reported in 2.1% and minor complications in 5.9% of cases. Bile duct injury was reported to be significantly more common after attempted laparoscopic cholecystectomy (11/3319, 0.33%) than after open cholecystectomy (4/8035, 0.06%) (95% confidence intervals -0.48 to 0.08), but it was not significantly different from that reported for laparoscopic cholecystectomy in the combined world literature (28/9322, 0.3%) (95% confidence intervals -0.19 to 0.25). Most systemic complications were significantly more common after open cholecystectomy. For open cholecystectomy, the mortality was 55/8035 (0.76%), with major complications reported in 3.2% and minor complications in 9.8% of patients. Adoption of the laparoscopic approach was associated with a four-fifths reduction in the mortality of cholecystectomy, and a 40% reduction in the overall complication rate when compared with the open operation. While laparoscopic cholecystectomy has an impressively low mortality and morbidity profile during the first 2 years of its introduction into the UK, prevention of bile duct injury is the most important issue to be addressed in all laparoscopic cholecystectomy training programmes.

Bile Ducts↗
PubMed1993

Giant cell fibroblastoma.

A report of a 1 1/2-year-old male child diagnosed as a case of giant cell fibroblastoma is described and the available literature on this neoplasm is reviewed. The tumor consists of a mixture of spindle cells and multinucleated giant cells in a myxoid or collagenous background. The pathological findings and clinical course suggest that these tumors be classified with fibromatoses of childhood. Removal of the tumor with wide excision is sufficient and these patients do not require any form of chemotherapy.

Fibroma↗
PubMed1993

Observations of angina and myocardial infarction in constrictive pericarditis.

The common symptoms of constrictive pericarditis, i.e. dyspnea on exertion, shortness of breath and cough, relate to impairment of ventricular filling and to a progressive rise in systemic and pulmonary venous pressures. Myocardial ischemia, angina and myocardial infarction are rarely associated with this disease. We have encountered two patients with constrictive pericarditis, one presenting with angina and the other with acute anterior wall infarction. Possible etiologies of constrictive pericarditis in the first case include cardiac surgery, chronic renal failure and myocarditis; in the second case, Crohn's disease. The proposed mechanism of chest pain in the first patient was a reduced cardiac output resulting in underperfusion of the coronary arteries, although it is possible that the patient experienced angina due to the presence of severe coronary artery disease. In the second patient an anterior wall infarction and post-infarction angina were attributed to obliteration of the left anterior descending artery by constraint of a thickened pericardium. In both cases non-invasive imaging modalities were not of use in establishing the diagnosis of constrictive pericarditis. Clinical awareness and accurate hemodynamic measurements continue to play a key role in the diagnostic process.

Angina Pectoris↗
PubMed1993

H-ras-1 restriction fragment length polymorphism in normal individuals and oral cancer patients in India.

Restriction fragment length polymorphism (RFLP) of the human H-ras-1 gene has been indicated as a marker for detection of individuals at high risk of cancer. We have investigated the association of RFLP at the H-ras-1 locus and susceptibility to oral cancer by Southern hybridization analysis in 77 primary oral tumors and 99 healthy donors. The frequency distribution of the BamHI fragments of H-ras-1 revealed homozygous or heterozygous alleles in the two subpopulations. The heterozygous genotype occurred more frequently in the normal subjects (53%) as compared to the cancer patients (36%). Four common alleles-C1 to C4, were noted predominantly in both groups, with rare alleles detected at a lower frequency. The common allele with 7.6 kb BamHI fragment was significantly higher in normals (10%) than in the tumor population (4%) (P < 0.05). However, a similar distribution of rare alleles in both groups indicated that the presence of rare alleles is not indicative of predisposition to oral cancer.

Alleles↗
PubMed1993

Septal perforator artery angioplasty: the advantage of application of an ultralow-profile balloon system--a case history.

Coronary artery disease can affect the septal perforator arteries and cause clinical sequelae, including angina, infarction of the interventricular septum, arrhythmias, and congestive heart failure. However, the size and the course of the septal perforator arteries significantly differ from those of the major epicardial coronary vessels. These anatomic features present certain technical challenges for angioplasty of the septal arteries. This case demonstrates that application of an ultralow-profile balloon-over-the-wire system can meet the specific requirements of septal artery angioplasty and achieve adequate results.

Aged↗
PubMed1993

Maxillary extragonadal germ cell tumor: a case report.

A single case report of a patient with primary extragonadal endodermal sinus tumor affecting the maxillary region is reported here. The patient was treated with combination chemotherapy consisting of bleomycin, cisplatin and etoposide. The child achieved complete remission and is now disease free for three years.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Myelodysplastic syndrome. A clinical and pathological analysis of 88 patients.

Eighty eight patients with myelodysplastic syndromes were studied to determine the clinical and pathological features and the prognosis. All the patients had anemia. Neutropenia was seen in 44% and thrombocytopenia in 78% patients. The subtypes included refractory anemia in six, refractory anemia with ringed sideroblasts in three, refractory anemia with excess blasts in 30, refractory anemia with excess blasts in transformation in 32 and chronic myelomonocytic anemia in 17 patients. Forty four patients who received chemotherapy were evaluable for response. Three of the 15 patients treated with hydroxyurea achieved partial remission. Eighteen patients were treated with low dose cytosine arabinoside and complete remission was achieved in five and partial response in six patients. Aggressive chemotherapy was given to 11 patients at the onset of the illness resulting in complete remission in six and partial response in two patients. Nineteen of the 88 patients transformed to acute myeloid leukemia. The crude survival of all the patients ranged from 15 days to 22.5 months. The mortality was due to hemorrhage in 15% and septicemia in 85%. Our data reveals ineffectiveness of the current therapy and emphasizes on the need to develop newer therapeutic approaches.

Adolescent↗
PubMed1993

Protocol for out-patient management of dengue illness in young adults.

A prospective study on the practicality of an out-patient management protocol for dengue infection in adults was carried out during a 2-month period. Doctors were requested to follow the protocol and assessment was done on the patients' outcome, the admission rate, and the compliance to the protocol by doctors and patients. One hundred and sixty-two patients (mean age 27.3 years) were clinically diagnosed to have dengue illness. Among them, 82.7% had dengue fever (DF); 13.0% had dengue haemorrhagic fever (DHF) and 4.3% had dengue shock syndrome (DSS). Dengue aetiology was confirmed in 69.4% of the DF group and 85.7% of the DHF and DSS groups. There were no deaths among the 162 patients. The admission rate was 43.8%. A high compliance rate of 86.4% by the doctors and a low patient default rate of 16.4% showed that the protocol was practical.

Adolescent↗
PubMed1993

Breath acetone analyzer: diagnostic tool to monitor dietary fat loss.

Acetone, a metabolite of fat catabolism, is produced in excessive amounts in subjects on restricted-calorie weight-loss programs. Breath acetone measurements are useful as a motivational tool during dieting and for monitoring the effectiveness of weight-loss programs. We have developed a simple, easy-to-read method that quantifies the amount of acetone in a defined volume of exhaled breath after trapping the sample in a gas-analyzer column. The concentration of acetone, as measured by the length of a blue color zone in the analyzer column, correlates with results obtained by gas chromatography. Using the breath acetone analyzer to quantify breath acetone concentrations of dieting subjects, we established a correlation between breath acetone concentration and rate of fat loss (slope 52.2 nmol/L per gram per day, intercept 15.3 nmol/L, n = 78, r = 0.81). We also discussed the possibility of using breath acetone in diabetes management.

Acetone↗
PubMed1992

The Vineberg procedure revisited: angiographic evaluation and coronary artery bypass surgery in a patient 21 years following bilateral internal mammary artery implantation.

A patient receiving bilateral internal mammary implantation (Vineberg's operation) in 1969 was symptom free for a period of 21 years. In 1990 he developed acute myocardial infarction followed by post-infarction angina. Cardiac catheterization revealed severe left main and three vessel disease and patency of both mammary implants which filled the left anterior descending and circumflex coronary arteries via collaterals. Coronary artery bypass surgery was indicated due to the native coronary artery disease and inability of the internal mammary grafts' blood flow to alleviate symptoms. The patient underwent direct coronary artery bypass grafting utilizing femoral vessels for cannulation and saphenous veins for grafting, while preserving the mammary implants. This unique case attests to the longevity of the internal mammary artery grafts. These grafts, even if directly implanted, can serve as a crucial source of blood to an otherwise severely underperfused myocardium. Strategy and technical aspects of surgical redo in patients who underwent Vineberg's operation are discussed.

Aged↗
PubMed1992

Evaluation of quinapril on regional blood flow and cardiac function in patients with congestive heart failure.

Quinapril, a nonsulfhydryl ACE inhibitor, was evaluated in ten New York Heart Association (NYHA) functional class (FC) II-III CHF patients to determine its effects on regional blood flow [effective renal plasma flow (ERPF), renal blood flow (RBF), renal vascular resistance (RVR), hepatic blood flow (HBF), hepatic vascular resistance (HVR), segmental limb pressure (SLP), creatinine clearance (CRCL)] and cardiac function [left ventricular ejection fraction (LVEF)]. Previous vasodilator therapy was withdrawn 2 weeks before baseline measurements. Stable regimens of digoxin and diuretics were continued throughout the study. ERPF was assessed using p-aminohippurate (PAH), HBF by indocyanine green (ICG) clearance, and LVEF by radionuclide scintography. Segmental limb pressures were measured by Doppler flow detection. Measurements were performed at baseline (B) and after 4 weeks of quinapril therapy (10 mg BID). Quinapril increased renal (P less than 0.05) and hepatic blood flow (P = 0.06) and significantly reduced renal and hepatic vascular resistance. Glomerular filtration rate and left ventricular ejection fraction were unchanged. Mean arterial pressure and brachial segmental pressures decreased without change in heart rate. Noninvasive cardiovascular assessments indicate that quinapril improves regional blood flow while exhibiting no change in left ventricular ejection fraction, in patients with NYHA FC II-III CHF.

Antihypertensive Agents↗