PubMed Health⌕ Search

Biomedical subjects

S Naik

Publications and source records attributed to S Naik.

At least 19 recordsLinked to original sources
PubMed1992

Is repeated coronary surgery for recurrent angina cost effective?

Between January 1980 and May 1988, 1363 patients underwent first time coronary artery bypass grafting (CABG) and 49 (3.6%) were reoperated for recurrent angina by the same surgeon in this unit. There were 42 males and five females with a mean age of 53.6 years. Mean time since first operation was 68.9 (37 SD) months. Prior to surgery only eight (16.3%) were still working. There were three hospital deaths and two late deaths at 2.5 and 3.5 years after surgery and one patient underwent cardiac transplantation at 1.5 years. Follow-up has been completed up to March 1989, mean 3.7 years, range 10-108 months. Questionnaires were sent to all patients concerning the financial and functional situation. Hospital expenses were calculated (a) prospectively for 15 consecutive first time CABGs and for five second time CABGs, (b) retrospectively from patients' records with the help of a simple computer programme. The final figures were corrected for inflation rates. The 1- and 5-year actuarial probability of angina-free interval was 87.5% and 40% respectively. Eight patients (12.2%) had no benefit, six (13.6%) had benefit but were not able to work, 16 (36.4%) were able to work but unemployed and 14 (13.8%) were fully employed producing a total salary of 69,072 pounds per annum. Hospital expenses were: first time CABG 3645-4049 pounds, second time CABG 6290-7235. The total for the entire group was 308 166 pounds. Repeated coronary surgery can be accomplished with reasonable mortality and has good late results.(ABSTRACT TRUNCATED AT 250 WORDS)

Actuarial Analysis↗
PubMed1992

Scleromyxoedema with features of systemic sclerosis.

The case is described of a patient with scleromyxoedema with features typical of systemic sclerosis. The features were so characteristic that the disease was misdiagnosed as systemic sclerosis. A brief review of the association of the two diseases is given.

Adult↗
PubMed1992

Influence of different substrates in detoxification activity of adult rat hepatocytes in long-term culture: implications for transplantation.

Substrates used to immobilize hepatocytes for transplantation govern attachment and long-term metabolic activity of these cells. The choice of these substrates is based on the familiarity with proteinaceous materials that are constituents of the extracellular matrix. The use of substrates that recognize carbohydrates on the cell surface may provide an alternative method to attach adult mammalian hepatocytes. In this study, immobilized lectins on tissue culture plasticware were used to support hepatocyte attachment. Long-term cultures with these substrates were compared with control cultures seeded on a mixture of collagen types I and III (Vitrogen). To evaluate the attachment efficiency and long-term maintenance of diazepam metabolic activity of hepatocytes seeded on different commercially available plasticware, four different types of polymers (supplied as 60-mm dishes) were tested. Diazepam, a benzodiazepine metabolized by the P450 intracytoplasmic pathway, is associated with a synaptic receptor (GABA-benzodiazepine receptor) which plays an important role in hepatic coma. Polymethylpentene, a derivative of polypropylene treated by plasma discharge, was the best polymer to maintain P450 phenotypic expression, although other polymers provided similar cell attachment efficiencies. The amounts of adsorbed concanavalin A, Arachis hypogaea (peanut), Lens culinaris, and Pisum sativum agglutinin correlate with the percentage values of hepatocyte attachment. Cell attachment to wheat germ agglutinin increased with increased lectin concentrations in spite of constant amounts of adsorbed lectin, whereas hepatocyte attachment to Bandieraea simplicifolia agglutinin was lower and did not change at different lectin concentrations.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1992

The use of placenta in a microvascular exercise.

Twenty-five human placentas were studied for suitability in a microvascular exercise. The size and useful length of vessels were measured, and different microvascular anastomoses were performed. The size of the placenta vessels compared well with reported sizes of intracranial arteries. We suggest the use of placenta by neurosurgeons as complementary to experimental animals in microvascular training.

Anastomosis, Surgical↗
PubMed1992

Prevalence of antibodies to hepatitis C virus in HBsAg negative hemodialysis patients.

The prevalence of hepatitis C virus (HCV) infection was estimated in a 14-month study using anti-C100-3 antibody assay in 31 HBsAg negative patients on maintenance hemodialysis (MHD) for > or = 3 months. One and three patients respectively had ALT elevation and anti-HCV positivity at entry. During MHD (mean period of follow up 9.9 mo), 11 (35.5%) patients had, on fortnightly estimation, ALT elevation which lasted for < or = 6 months in seven patients and for > 6 months in four. Fourteen (45.2%) patients had anti-HCV (including the three positive at entry). There was no significant difference in frequency of anti-HCV positivity in patients with normal and elevated ALT (57.1% and 42.9% respectively). The number of blood transfusions and duration of MHD were similar in anti-HCV positive and anti-HCV negative patients. We conclude that our MHD patients have a high frequency of hepatitis and anti-HCV positivity, and these may not be related to blood transfusions.

Adult↗
PubMed1992

Explosive Campylobacter jejuni diarrhea in immunoproliferative small intestinal disease.

Campylobacter jejuni is an infrequent cause of self limiting acute diarrheal disease in adults in the Indian subcontinent. We report the occurrence of a life threatening diarrhea due to C jejuni infection in a patient with immunoproliferative small intestinal disease. We postulate that immunosuppression due to malignancy, malnutrition and cancer chemotherapy was responsible for the unusually severe diarrhea.

Adult↗
PubMed1992

Filter paper blood spot test for detection of anti-ND-BSA antibodies in school children.

For identifying individuals at 'high risk' for developing leprosy, a simplified technique of collection of blood samples on filter paper for detection of anti -ND-BSA antibodies, was optimised. Anti-ND-BSA antibody reactivity on the filter paper was lost on storage at room temperature, but was stable at least for a period of 8 wk at lower temperature. Among the 1495 children screened, 166 (11.1%) were lepromin negative and 122 (8.2%) positive for anti-ND-BSA antibody. In the first phase, 7 of 871 children followed up for 2 yr developed leprosy, while in the second phase 2 of 624 children followed-up for 9 yr developed leprosy. The positivity and negativity of anti-ND-BSA antibodies and lepromin in these I children indicate that the positive status for anti-ND-BSA antibodies has a better predictive value than negative lepromin reactivity. Measurement of anti-ND-BSA antibodies was also of value for monitoring the efficacy of therapy and course of the disease. Extrapolation of the two tests to the total population of children evaluated showed that an individual with negative lepromin reactivity along with presence of anti-ND-BSA antibodies is at a higher risk for developing leprosy than those who have both the tests normal. Lepromin reactivity alone was not of much value for the prediction for development of the disease. However, the presence of anti-ND-BSA antibody was a better indicator for the development of the disease. The probability of developing leprosy in a child with any one of the tests abnormal was higher as compared to a child having all the tests normal.

Adolescent↗
PubMed1990

Phenobarbital induction of cytochromes P-450. High-level long-term responsiveness of primary rat hepatocyte cultures to drug induction, and glucocorticoid dependence of the phenobarbital response.

The induction of hepatic cytochromes P-450 by phenobarbital (PB) was studied in rat hepatocytes cultured for up to 5 weeks on Vitrogen-coated plates in serum-free modified Chee's medium then exposed to PB (0.75 mM) for an additional 4 days. Immunoblotting analysis indicated that P-450 forms PB4 (IIB1) and PB5 (IIB2) were induced dramatically (greater than 50-fold increase), up to levels nearly as high as those achieved in PB-induced rat liver in vivo. The newly synthesized cytochrome P-450 was enzymically active, as shown by the major induction of the P-450 PB4-dependent steroid 16 beta-hydroxylase and pentoxyresorufin O-dealkylase activities in the PB-induced hepatocyte microsomes (up to 90-fold increase). PB induction of these P-450s was markedly enhanced by the presence of dexamethasone (50 nM-1 microM), which alone was not an affective inducing agent, and was inhibited by greater than 90% by 10% fetal bovine serum. The PB response was also inhibited (greater than 85%) by growth hormone (250 ng/ml), indicating that this hormone probably acts directly on the hepatocyte when it antagonizes the induction of P-450 PB4 in intact rats. In untreated hepatocytes, P-450 RLM2 (IIA2), P-450 3 (IIA1) and NADPH P-450 reductase levels were substantially maintained in the cultures for 10-20 days. The latter two enzymes were also inducible by PB to an extent (3-4 fold elevation) that is comparable with that observed in the liver in vivo. Moreover, P-450c (IA1) and P-450 3 (IIA1) were highly inducible by 3-methylcholanthrene (5 microM; 48 h exposure) even after 3 weeks in culture. In contrast, the male-specific pituitary-regulated P-450 form 2c (IIC11) was rapidly lost upon culturing the hepatocytes, suggesting that supplementation of appropriate hormonal factors may be necessary for its expression. The present hepatocyte culture system exhibits a responsiveness to drug inducers that is qualitatively and quantitatively comparable with that observed in vivo, and should prove valuable for more detailed investigations of the molecular and mechanistic basis of the response to PB and its modulation by endogenous hormones.

Animals↗
PubMed1989

In vitro activities of several new macrolide antibiotics against Mycobacterium avium complex.

The in vitro activities of 12 macrolide compounds against 28 Mycobacterium avium complex strains isolated from patients with acquired immunodeficiency syndrome were determined by the conventional proportion method and by the BACTEC method. Clarithromycin (A-56268; TE-031), a new macrolide compound, was the most active agent tested, inhibiting 90% of strains at an MIC of 4 micrograms/ml by the BACTEC method. Roxithromycin (RU 28965) and erythromycylamine inhibited 90% of strains at 16 micrograms/ml. The organisms showed high levels of resistance to most other macrolide compounds.

Acquired Immunodeficiency Syndrome↗
PubMed1989

Comparative study of oral and intramuscular atropine sulphate as a premedicant in paediatric age group.

The use of atropine sulphate in the paediatric age group as a premedicant orally in a dosage of 0.02 mg/kg body weight 70 minutes prior to surgery was found to be as effective as atropine sulphate given intramuscularly 35 minutes prior to surgery in a dosage of 0.01 mg/kg body weight. This avoids the unpleasant memory of needle prick; The duration of effect as studied in the normal healthy children not subjected to surgery was found to be 2 1/2-3 hours.

Administration, Oral↗
PubMed1989

Post infarction ventricular septal defect. Review of 41 surgical cases.

Forty-one patients with ventricular septal rupture after myocardial infarction were operated over about a 4-year period. The "early" group included 17 patients operated upon within the first 24 hours and 13 of them died. A total of 29 patients were operated within the first week and 21 died. The other 12 were operated after the first week since the diagnosis was made and 11 (92%) survived. The most relevant risk factors were: cardiogenic shock, hypertension and diabetes. The initial management was based on digitalis, diuretics, inotropes (dopamine, dobutamine) and the intra-aortic balloon pump. There was no significant difference in mortality between those patients with associated procedures and those without them, except in those cases of coronary grafts with infartectomy, whose mortality was higher. Early surgical repair of ventricular septal rupture implies a very high mortality (72%), which is even worse when the operation is performed within the first 24 hours (76%).

Aged↗
PubMed1988

Seasonal distribution in conceptions achieved by artificial insemination by donor.

The distribution of conceptions after artificial insemination from a donor was studied in 259 conceptions at an artificial insemination clinic and found to be seasonal. Conception was not influenced by the number of donors or patients attending the clinic, the frequency of inseminations, or medical skill. Conception was more common from early winter until early spring (October to March) with a peak in November. As variables such as frequency of intercourse and ovulation were irrelevant in these women and highest sperm counts occur from February to March these results suggested a seasonal variation in the quality of the ovulated egg or endometrial receptivity. The waste of eggs after ovulation (or preimplantation conceptuses) at specific times of the year has implications in the treatment of infertility, particularly for in vitro fertilisation and gamete intrafallopian transfer.

England↗
PubMed1988

A quantitative analysis of lectin binding to adult rat hepatocyte cell surfaces.

A quantitative evaluation of lectin binding to adult rat hepatocyte cell surfaces was done using cells isolated by two different collagenase perfusion methodologies and cultured as monolayers with two different tissue culture media formulations (protocol I vs. protocol II). The presence of alpha-D-mannosyl and alpha-D-glucosyl groups was detected by the binding of Concanavalin A (Con A), Lens culinaris agglutinin (LCA), and Pisum sativum agglutinin (PSA) to freshly isolated cells. Furthermore, beta-D-galactose [Ricinus communis agglutinin (RCA)] and sialic acid residues [wheat germ (WGA)] were also found. Protocols I and II served as models for evaluation of: a) the stripping effect of collagenase separation procedures, b) the restoration in culture of collagenase-stripped sugar residues, c) the effect of the culture environment on cell viability [as measured by lactic acid dehydrogenase (LDH) leakage] and the protein content of hepatocytes, and d) the presence of cell surface sugar residues as a function of culture duration. The ultrastructural morphology of freshly isolated and cultured hepatocytes was also evaluated. These studies indicated that a decline in lectin binding invariably occurred earlier than a massive leakage of LDH and a decrease in the protein content of the cells in culture. Ultrastructurally, autophagocytosis was an early phenomenon in cells isolated and cultured by protocol I, which was also inferior to protocol II regarding the preservation of hepatocyte glycocalyces. Sugar residues lost due to the collagenase-stripping effect were restored, as shown by lectin binding, within the first 24 h of culture. This stripping effect was confirmed by quantitative evaluations of lectin binding to hepatocytes in culture after an incubation with collagenase. This study shows that the binding of peroxidase-labeled lectins is a useful tool for quantitative evaluation of the sugar composition of hepatocyte cultures.

Animals↗
PubMed1988

Hepatocyte cell surface polarity as demonstrated by lectin binding.

We performed an investigation at the ultrastructural level of the differential distribution of lectin-binding sites among sinusoidal, lateral, and bile canalicular domains of adult rat hepatocytes. Lectin binding to hepatocyte glycocalices was studied in situ or after cellular dissociation by enzymatic (collagenase), chemical (EDTA), and mechanical methods, as well as during cell culture. Using thirteen biotinylated lectins and an avidin-biotin-peroxidase complex (ABC), we have identified lectin-binding sites that are predominantly localized in the bile canalicular [Ricinus communis agglutinin (RCA)] or sinusoidal [Phaseolus vulgaris (PHA)] domains in situ and in mechanically dissociated cells. Lens culinaris (LCA) staining was prominent on sinusoidal surfaces, slight along lateral surfaces, and completely absent in the bile canalicular domain. Concanavalin A (ConA) was unique in binding equally to all domains. Triticum vulgaris [wheat germ agglutinin (WGA)] was also bound to all domains, but most intensely to the bile canalicular region. Cells dissociated via collagenase or EDTA treatment exhibited a spherical morphology characterized by many surface microvilli and absence of morphological domains. Lectin binding to dissociated cells was uniformly distributed over the entire cell surface, suggesting a redistribution of lectin receptors that was independent of the separation procedure. Hepatocytes in culture exhibited a partial restoration of morphological domains, but lectin binding polarity was not re-established.

Animals↗
PubMed1988

Persistence of heart reactive antibodies (HRA) in acute rheumatic fever (ARF) and rheumatic heart disease (RHD) patients.

Heart Reactive Antibodies (HRA) of IgG and IgM classes were investigated in 79 patients in four clinically classified groups. Group I comprised of 16 children with Acute Rheumatic Fever (ARF) and Group II consisted of 15 cases with active Rheumatic Heart Disease (RHD). Twenty seven cases of ARF and RHD in remission and 21 adults with quiescent RHD were included in Groups III and IV respectively. Control groups comprised of 14 normal, healthy, donors and eight Post Streptococcal Acute Glomerular Nephritis (PSAGN) cases. Low levels of HRA of IgG and IgM classes were detected in control groups. The overall incidence of HRA of IgG and IgM classes was 82.28 and 39.24% respectively in the patient group. An increased frequency of HRA-IgM antibodies was observed in Groups I, III and IV (p less than 0.01, 0.001 and 0.025 respectively). All the four groups demonstrated a highly significant increase in incidence of HRA--IgG class (p less than 0.0005). Persistence of high titres of HRA-IgG class in ARF and RHD is reported in the paper.

Adolescent↗