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Biomedical subjects

S Kumar

Publications and source records attributed to S Kumar.

At least 703 records · Page 39Linked to original sources
PubMed2000

Ontogeny of valproic acid disposition and metabolism: a developmental study in postnatal lambs and adult sheep.

The ontogeny of valproic acid (VPA) disposition and metabolism was investigated in developing lambs and adult sheep (Dorset or Suffolk breed). Specifically, we wished to investigate the role of glucuronidation and beta-oxidation on VPA elimination during development. Catheters were implanted in a carotid artery, a jugular vein, and the urinary bladder in 10-day-old (10 d; n = 8), 1-month-old (1 M; n = 4), and 2-month-old lambs (2 M; n = 5). In adult sheep (n = 5), catheters were implanted in a femoral artery and vein. After the administration of a 10 mg/kg VPA i.v. bolus, serial blood samples and cumulative urine samples were collected for 36 h in the adult ewes and for 72 h in the lambs. Due to saturable protein binding, age-related differences in VPA clearance were more obvious when examining the total body clearance of unbound drug (Cl(u)tb). Mean Cl(u)tb increased significantly with age up to 2 months (10 d = 2.65 +/- 1.16 ml/min/kg; 1 M = 5.11 +/- 2.49 ml/min/kg; 2 M = 12.84 +/- 3.88 ml/min/kg) before decreasing to adult levels (7.73 +/- 2.64 ml/min/kg). Similarly, the urinary recovery of the major metabolite, VPA-glucuronide, was significantly less in 10 d lambs (29.2 +/- 16.0% of the dose) when compared with the adult and 2 M groups (both approximately 74% of the dose). No differences with age were observed in the portion of the dose excreted as the beta-oxidation metabolite, 2-n-propyl-3-oxopentanoic acid. The results suggest that alterations in Cl(u)tb with age may be attributable to postnatal development of enzymes involved in VPA glucuronidation.

Age Factors↗
PubMed2000

Evaluation of E test for susceptibility testing of Mycobacterium tuberculosis to primary anti tubercular drugs.

BACKGROUND & OBJECTIVES: Antimicrobial susceptibility tests for tuberculosis take weeks and delayed therapy can lead to an increase in disease incidence. The E test is a new concept for minimum inhibitory concentrations (MIC) determinations for antimicrobial agents that is based on a predefined antibiotic gradient on a plastic strip calibrated with a continuous logarithmic MIC scale covering 15 two-fold dilutions. The present study was undertaken to evaluate E test strips for susceptibility testing of Mycobacterium tuberculosis. METHODS: Twenty five clinical isolates of M. tuberculosis were tested for the four first line antitubercular drugs by E test and were compared with standard proportion method. The inoculum turbidity was adjusted to McFarland 3.0 standard and agar plates (Middle brook 7H11 agar) were inoculated and preincubated (37 degrees C in 7-10% CO2) for 24 h after which time, the E test strips were placed on the agar surface which were incubated under same conditions. The MIC was interpreted as the point at which the ellipse intersected the 'E test' strip as described in E test technical guide. RESULTS: Of the 25 strains, susceptibility as determined by both methods for isoniazid (INH), rifampin, ethambutol and streptomycin was found in 22 (88%), 20 (80%), 24 (96%) and 18 (72%) strains respectively. Agreement between E test and proportion method was 96 per cent for INH, 92 per cent for rifampin and 100 per cent for ethambutol and streptomycin each. However, sensitivity could be predicted after 7-10 days by E test and exact MIC could also be determined. INTERPRETATION & CONCLUSIONS: E test method was found to be rapid, accurate, reliable and easy to perform. It can be employed for routine susceptibility testing for antitubercular drugs.

Antitubercular Agents↗
PubMed2000

Thalamic epidermoid cyst. A case report.

A case of thalamic epidermoid cyst is reported. Its clinical presentation, radiological, operative findings and histological findings are discussed. Intraparenchymal epidermoids are uncommon and to our knowledge only one case of thalamic epidermoid has been reported earlier. The literature is reviewed in regard to incidence, location and etiology of Intracerebral epidermoid tumor cysts.

Adult↗
PubMed2000

Endogenous bradykinin and the renin and pressor responses to furosemide in humans.

In humans, bradykinin contributes to the acute renin response after ACE inhibition. To further explore the role of endogenous bradykinin in human renin regulation, we determined the effect of HOE 140, a specific bradykinin B(2) receptor antagonist, on the renin response to 0.5 mg/kg i.v. furosemide in a randomized, single blind, crossover design study of 10 healthy, salt-replete volunteers. HOE 140 did not affect basal plasma renin activity, aldosterone, mean arterial pressure, or heart rate. Furosemide administration increased plasma renin activity from 1.0 +/- 0.2 to 4.5 +/- 1.2 ng of angiotensin I/ml/h and there was no effect of HOE 140 (from 1.1 +/- 0.2 to 3.9 +/- 0.8 ng of angiotensin I/ml/h). Similarly, there was no effect of HOE 140 on the diuretic response to furosemide. Mean arterial pressure increased in response to furosemide after HOE 140 (82 +/- 2 to 94 +/- 2 mm Hg), but not after vehicle (81 +/- 3 to 85 +/- 2 mm Hg), whereas heart rate was unchanged. In conclusion, activation of the B(2) receptor by endogenous bradykinin does not contribute to the renin response to acute furosemide treatment in humans. However, bradykinin may contribute to blood pressure regulation under conditions in which the renin-angiotensin system is stimulated.

Adrenergic beta-Antagonists↗
PubMed2000

cAMP increases the expression of human angiotensinogen gene through a combination of cyclic AMP responsive element binding protein and a liver specific transcription factor.

Angiotensinogen is the glycoprotein precursor of one of the most potent vasoactive hormones angiotensin-II which plays an important role in the regulation of blood pressure. We show here that the promoter activity of reporter constructs containing human angiotensinogen promoter is increased by cAMP treatment on transient transfection in HepG2 cells. We have identified a composite cAMP responsive element, located around 840 bases upstream from the transcriptional initiation site, in the promoter of human angiotensinogen gene. This element is recognized by members of CREB/ATF as well as C/EBP family of transcription factors. Another C/EBP binding site that is not recognized by CREB is located 10 bases upstream from this site. We show that co-transfection of CREB increases the promoter activity of reporter constructs containing human angiotensinogen gene promoter attached to the CAT gene. We also show that co-transfection of DBP (which is a member of C/EBP family of transcription factors) increases promoter activity of these reporter constructs.

Activating Transcription Factor 1↗
PubMed2000

Surgical speech restoration by tracheo-oesophageal puncture--Kidwai experience.

This paper addresses our experience with primary (15 patients) and secondary (8 patients) tracheo-oesophageal puncture (TEP) in the laryngectomee. Despite a success rate of 93.3 percent in the primary TEP and 62.5 percent in secondary TEP, in a follow-up period of one month to eight years, prosthesis related problems like maintenance and recurring expenses emerged as significant deterrent factors in adopting prosthetic speech rehabilitation. Successful oesophageal speech training, increased practice of Pearson's near total laryngectomy, prior tracheostomy and advanced disease mandating post-operative radiotherapy in majority of patients are some of the factors in addition to prosthesis after-care maintenance that makes TEP a less practiced option at our center.

Esophagus↗
PubMed2000

Diverse manifestation of arrhythmogenic right ventricular dysplasia in a family.

Arrhythmogenic right ventricular dysplasia (ARVD) is a cardiomyopathy of unknown cause associated with life-threatening arrhythmias. The purpose of this case report is two-fold: (i) To highlight the utility of a definite set of diagnostic criteria encompassing structural, histologic, electrocardiographic, arrhythmic and genetic factors in establishing diagnosis of ARVD in institutions like ours which are handicapped by lack of magnetic resonance imaging (MRI) and endomyocardial biopsy facilities, (ii) to present diverse arrhythmic manifestations in a single family.

Adolescent↗
PubMed2000

Need for bringing in a change in biochemistry curriculum to make it clinically oriented?

OBJECTIVES: This study was conducted to (a) assess the views of medical students and doctors regarding relevance of biochemistry training, (b) explore if they have any suggestion to bring in any improvement in contents of biochemistry curriculum and mode of teaching. METHODS: In 1997-98, a structured questionnaire was filled up by 114 medical students and 118 doctors. RESULTS: As many as 62/114 (55%) medical students and 40/118 (34%) doctors believed that it is not important to remember minute details of biochemical reactions (p value < 0.0001). Among medical students, 108/110 (98.2%) agree that a clinician should be invited to seminars for developing skills of interpretation of laboratory investigations; whilst 110/118 (93.2%) doctors expressed similar view, p value ns. Approximately 92% responders favored that departments biochemistry and physiology should co-ordinate on the topics of common interest in order to save time and effort. What is the most informative and effective way of teaching biochemistry?' in response to this question only 0.9% responders opted lecture as the best option. Seminars with active participation of medical students was preferred by 93.2% responders. About 6.9% responders reckoned that symposium prepared by a more than one teacher. In response to the question whether it is possible to cover pre-clinical subjects in 12 months so as to allow spiral mode of curriculum, 73% of all the responders agreed that it would be good idea, there was no difference of opinion among the doctors and medical students. On the other hand, 27% were strongly opposed to this suggestion. CONCLUSIONS: We suggest that there is a need to modify the contents, methods of teaching, and curriculum organization of training in clinical biochemistry. How best the curriculum can be made problem oriented needs to be debated among medical educationists.

Biochemistry↗
PubMed2000

A study of dietary pattern, household food security and nutritional profile of under-five children of a community of West Bengal.

A cross-sectional study was carried out in a tribal community of West Bengal to study the dietary pattern, household food security, utilisation of services and nutrition profile of under-five children. It was observed that average calorie consumption was 2,236 with 48% food insecured families. Cereals, starchy food and green leafy vegetables consumption was higher than the recommended daily allowance while pulses (scarcely supplied in fair price shops), milk, oil and sugar were less than recommended daily allowance. Nearly 11% kcal were coming from alcohol consumption. Public distribution system should supply all essential items with an improved quality on a regular basis and supply during lean season should be ensured. Prevalence of malnutrition in the children under-five years of age was 80.90% and 9.26% were suffering from severe grades. More severely malnourished children were observed in the age group of 12-23 months, amongst female children, in the families where mothers were working and also in the families where numbers of sibling were 2 or more. Services available under Integrated Child Development Services Scheme were utilised by 47.3% children.

Breast Feeding↗
PubMed2000

Evaluation of vitamin A status during pregnancy.

Adequate maternal vitamin A nutrition is essential for successful pregnancy outcome and estimation of serum retinol among pregnant women enables a precise and objective assessment of vitamin A status, during pregnancy, even in subclinical state. In order to evaluate vitamin A status during pregnancy, and its relationship with personal and pregnancy related variables of the mother, 300 antenatal clinic attenders were interviewed at RG Kar Medical College and Hospital, Calcutta and tested for serum retinol, using Carr-Price test. Serum retinol values less than 30 microg/dl and 20 microg/dl, in this study, were considered as poor and severe vitamin A deficiency respectively. According to this 14.7% and 4% pregnant women were found to be suffering from poor and severe vitamin A deficiency respectively. Clinical signs of vitamin A deficiency (eg, nightblindness) were reported only among 60% cases of the deficient population. The problems of vitamin A deficiency were associated with low literacy and poor nutritional status of the mother, advanced gestational age of current pregnancy,increased number of pregnancies, shorter interval between births and poor dietary intake of vitamin A rich foods during pregnancy. The study thus raises the question of supplementation of vitamin A, during pregnancy, in Indian context where habitual diets are either inadequate or deficient in vitamin A.

Adolescent↗
PubMed2000

Identification of yeasts from clinical specimens by oxidase test.

A total of 100 yeasts and yeast like fungi isolates from clinical specimens were negative for oxidase production on Sabouraud dextrose agar. When grown on Columbia agar, chocolate agar, tryptose agar, Mueller-Hinton agar, brain heart infusion and a medium resembling Sabouraud's dextrose agar but with starch instead of dextrose, all the isolate of Candida albicans (55), C. guilliermondii (6), C. parapsilosis (14), C. tropicalis (6), C. pseudotropicalis (6) and Crytococcus neoformans (2) were positive for oxidase producation. Torulopsis glabrata (2), Saccharomyces cervisiae (2) and two out of seven isolates of C. krusei were negative for oxidase test.

Culture Media↗
PubMed2000

Filariasis as a cause of pleural effusion.

Filariasis, a mosquito borne disease is endemic in many tropical countries and sub tropics including India. A 44 years old male presented with signs and symptoms of pleural effusion. Pleural fluid on examination was exdudative in nature and showed presence of microfilariae of Wuchereria bancrofti.

Adult↗
PubMed2000

A study of yeast carriage on hands of hospital personnel.

The present study was conducted by culture with a modified broth wash technique to examine the frequency of yeast carriage on the hands of 60 nurses and 35 nonnursing hospital employees. Seventy two percent of the nurses and 80% of the nonnurses were harbouring yeast on their hands. Candida spp. were isolated in 57% on of nurses and 34% of nonnurses. Ninety percent of nurses working in nursing home care unit (NHCU), 50% working in intensive care unit (ICU) and 75% working in outpatient department (OPD) carried yeasts on their hands. Only 80% of nonnurses staff harboured yeasts on their hands.

Ambulatory Care↗
PubMed1999

Interaction of ribonucleoside triphosphates with the gene 4 primase of bacteriophage T7.

The primase fragment of bacteriophage T7 gene 4 protein catalyzes the synthesis of oligoribonucleotides in the presence of ATP, CTP, Mg(2+) (or Mn(2+)), and DNA containing a primase recognition site. During chain initiation, ATP binds with a K(m) of 0.32 mM, and CTP binds with a K(m) of 0.85 mM. Synthesis of the dinucleotides proceeds at a rate of 3.8/s. The dinucleotide either dissociates or is extended to a tetranucleotide. The primase preferentially inserts ribonucleotides forming Watson-Crick base pairs with the DNA template >200-fold more rapidly than other ribo- or deoxynucleotides. 3'-dCTP binds the primase with a similar affinity as CTP and is incorporated as a chain terminator at a rate (1)/(100) that of CTP. ATP analogues alpha,beta-methylene ATP, beta,gamma-methylene ATP, and beta,gamma-imido ATP are incorporated by the primase fragment at the 5'-ends of the oligoribonucleotides but not at the 3'-ends. A model is presented in which the primase fragment utilizes two nucleotide-binding sites, one for the initiating ATP and one for the nucleoside triphosphate which elongates the primer on the 3'-end. The initiation site binds ATP or oligoribonucleotides, whereas the elongation site binds ATP or CTP as directed by the template.

Adenosine Triphosphate↗
PubMed1999

Tensions between policy makers and general practitioners in implementing new genetics: grounded theory interview study.

OBJECTIVE: To explore general practitioners' perceptions of their role in implementing genetic technology. DESIGN: Grounded theory interview study. SETTING: Primary care. SUBJECTS: Purposive sample of 30 general practitioners with a further theoretical sample of 14. RESULTS: Inconsistencies were identified between policy makers' and general practitioners' definitions of general practitioners' role in implementing the new genetics. General practitioners emphasised the need to build on current practice, whereas policy makers focused on transforming practice to include the new specialised roles and skills. Two core themes were identified: genetics in a generalist context, which included appropriate generalist intervention, the ethical dilemmas implicit in the "therapeutic gap," the familial-hereditary distinction in primary care, and the implications for generalist identity, including the potential marginalisation of generalism. CONCLUSION: New technologies such as genetics that require implementation in general practice should be integrated within existing generalist frameworks.

Ethics, Medical↗