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S Sharma

Publications and source records attributed to S Sharma.

At least 757 records · Page 42Linked to original sources
PubMed1996

Immunogenicity of the nonrepetitive regions of the circumsporozoite protein of Plasmodium knowlesi.

The circumsporozoite antigen (CS) of the simian malarial parasite Plasmodium knowlesi consists of tandemly repeated immunodominant peptide units that are variable and may play a role in evading the immune system. To study the immunogenicity of this antigen in the absence of the immunodominant repeats, the entire nonrepetitive region of the antigen was expressed in Escherichia coli as two fusion proteins with glutathione-S-transferase (GST) representing the amino terminal (GST-CSN) and the carboxy terminal domains (GST-CSC) of the CS antigen. The immunogenicity of these fusion proteins was studied in rabbits and different strains of mice. Antibody raised against both the CSN and CSC domains in both rabbits and every strain of mice recognized the native protein, as detected by immunofluorescence assay (IFA) using P. knowlesi sporozoites. A positive IFA reaction was also obtained with P. vivax sporozoites using antisera raised against the CSC domain. High titer antisera were raised in rabbits against both the domains, whereas mice showed comparatively low titers. On Western blots, mice showed specific response against the CSC domain. In both rabbits and mice, significant titers of antibodies were raised against region II, which has been shown to be the putative sporozoite binding site for hepatocytes in the case of P. falciparum.

Amino Acid Sequence↗
PubMed1996

Acceptability of epidural analgesia for pain relief during labour among Kelantanese women.

Three hundred and five primigravid women were interviewed at term to assess the acceptability of epidural during labour, and reasons for the decisions. Data was collected on a prestructured proforma which consisted of background information, socio-economic status, knowledge about epidural analgesia, source of information and reasons for choice. Of the 305 patients only 17.3% were willing to receive epidural analgesia. This group consisted of 56.6% non-Malay women. Those employed in professional or skilled jobs (56.6%) also readily consented for epidural. Nearly half the women willing for epidural had received college (tertiary) education (43.3%) and more than a quarter (26.4%) were over 30 years of age. The majority of those who were unwilling had no prior knowledge about the procedure, and refused either out of fear, ignorance, resistance from husbands, on religious grounds or following poor feedback from friends. In order to advocate epidural analgesia, knowledge has to be targeted to the relatively less educated, unemployed women, mainly through the media or personally in the antenatal clinic by doctors and nurses. Services have to be improved as substandard analgesia may send out wrong messages and actually do more harm than good.

Adult↗
PubMed1996

Multiplicity of glutamate receptor subunits in single striatal neurons: an RNA amplification study.

The RNA amplification technique was used to examine the pattern of coexpression of mRNAs encoding 16 subtypes/subunits of the glutamate receptor (GluR) in acutely dissociated neurons from adult rat striata. THe signal intensity for each mRNA varied within single neurons, but the general pattern of low versus high expression signals was similar among neurons, except for the GluR4 subunit of the (+/-)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor. The mRNAs for GluR1-3 subunits of the AMPA receptor were present in all cells, with the signal intensity of GluR1 mRNAs usually the lowest. The kainate receptor subunit mRNAs (GluR5-7) were present in most neurons, and the signal intensity for GluR6 mRNA was the highest. The signals for N-methyl-D-aspartate (NMDA)R1 and NMDAR2B mRNAs were high in most neurons; however, NMDAR2A and NMDAR2C mRNAs gave low or undetectable signals. For mRNAs encoding metabotropic GluRs (mGluRs), signals for mGluR1, mGluR2, and mGluR3 mRNAs were low or undetectable, whereas mGluR4 and mGluR5 mRNA signals were high in most neurons. In most cases (12 of 16 mRNAs), the results agreed with data from in situ hybridization experiments in which individual mRNAs were examined. All neurons expressed subtypes/subunits mRNAs for all four types of GluRs; however, there were differences in the relative intensity of the mRNA signals detected in individual cells, suggesting that these receptors could exist in various combinations within individual neurons and thus confer synapse-specific function for information processing in the striatum.

Animals↗
PubMed1996

Uretric obstruction in Gardener's syndrome.

Desmoid tumours in Gardener's syndrome are a rare cause of ureteric obstruction. We report two cases of ureteric obstruction caused by desmoids, in a mother and daughter.

Adult↗
PubMed1996

Microbiological quality & incidence of organisms of public health importance in food & water in Ludhiana.

Bacteriological analysis of 713 samples of various types of foods and related articles and potable water samples from different places in Ludhiana, Punjab was carried out. The highest counts ranging from 2.5 x 10(6)-7.5 x 10(8) organisms/g were observed in raw vegetables and fruits, followed by 3 x 10(6)-9.8 x 10(7)/ml, 8.3 x 10(4)-8.9 x 10(7)/g and 1 x 10(3)-6.7 x 10(7)/g in fruit juice, milk and its products, and salty/non milk snacks respectively. Fresh chapati, dal, rice, cooked vegetables and karhi etc., showed no microbial contamination. However, samples of these articles from road side cafes gave counts up to 1 x 10(7) organism/g. The most probable number of coliforms and Escherichia coli/100 ml of water ranged from < 1 to > 1100. Although 1332 isolates of 16 types of organisms of public health significance were obtained those of proven enteropathogenicity were enterotoxigenic Esch. coli (55), Esch. coli O157 (3), enteropathogenic Esch. coli (1), enterotoxigenic Klebsiella (23), Streptococcus faecalis (152), Bacillus cereus (133), Staphylococcus aureus (125), Aeromonas spp (47), Salmonella spp (10), Shigella spp (4) and Yersinia enterocolitica (2). Poor quality of potable water and widespread occurrence of enteropathogens in food consumed by the common man in Ludhiana was evident.

Food Microbiology↗
PubMed1996

Superficial versus deep: options in venous drainage of the radial forearm free flap.

We performed a fresh cadaver dissection study of the superficial venous system (cephalic vein and its branches) and the deep venous system (venae comitantes) of the radial forearm to assess the suitability of each system for venous anastomosis during free tissue transfer. We used methyl methacrylate to evaluate vessel diameters and anatomic variability of both venous systems. Colored radiopaque injectate allowed us to combine anatomic dissection with tissue radiographs. We discovered the cephalic vein to invariably be of larger caliber than the venae comitantes. Ensuring capture of the cephalic vein in the flap necessitated additional dorsoradial subcutaneous dissection beyond the boundaries of the skin flap in four of ten specimens. The vessel diameters of the venae comitantes in four cadavers were less than 2 mm. Proximal confluence of the two venae comitantes, and communication between the deep and superficial venous systems were encountered in only four cases. In these cases, had an anastomotic site been chosen proximal to such a communication to ensure greater vessel caliber, pedicle length probably would have made free tissue transfer unwieldy. We recommend mapping the course of the cephalic vein before flap elevation and maintaining a wide proximal subcutaneous pedicle to capture the best possible superficial drainage system. If the superficial venous system has been damaged (as by previous intravenous catheterization), one may not necessarily be able to rely on the vessel caliber of the deep venae comitantes for microvenous anastomosis.

Brachial Artery↗
PubMed1996

Bacterial infections in burns patients: a three years study at RML Hospital, Delhi.

A study was undertaken at RML Hospital, Delhi to examine the bacterial infections of burn cases and determine the antibiograms of the isolates to commonly used antimicrobial agents. A total of 489 pus samples from as many patients received, over a period of three years (January 1992 to December, 1994) yielded 793 isolates. Pseudomonas sp. was the commonest (53.9%) followed by Klebsiella sp. (35.1%) Staphylococcus aureus (30.6%) Proteus sp. (23.5%). Esch. coli (14.1%) and others (4.9%). The most resistant isolate to commonly used antimicrobial was Klebsiella sp. (16.4%), followed by Esch. coli (15.4%) Pseudomonas sp. (15.2%) Proteus sp. (7.8%) and Staphylococcus aureus (4.6%). The infection of burn wounds with multiple organisms, with superadded problem of drug resistance, indicate the institution of a drug policy by the hospitals for burns patients.

Bacterial Infections↗
PubMed1996

Donor corneal tissue evaluation.

Proper evaluation of donor cornea is critical to the success of corneal transplantation. Attention must be paid to the cause of death and ocular condition as several general and ocular diseases constitute contraindications for donor corneal usage. Death to enucleation time should be noted. Gross examination and slit lamp biomicroscopy are mandatory for the evaluation of the donor eye while specular microscopy adds another useful dimension to information regarding donor cornea. This article provides a comprehensive review of all the aspects of donor corneal evaluation as practised today worldwide.

Contraindications↗
PubMed1996

Development of food frequency questionnaires in three population samples of African origin from Cameroon, Jamaica and Caribbean migrants to the UK.

OBJECTIVES: To develop the methods for assessment of food and nutrient intake using standardized food frequency questionnaires (FFQ) in three African origin populations from Cameroon, Jamaica and Caribbean migrants to the United Kingdom. DESIGN: Cross-sectional assessment of diet from a representative sample in each site, using either a 2-day food diary or a 24-h recall method to determine foods for inclusion on the food frequency questionnaire. SETTING: A rural and urban site in Cameroon, Evodoula and Cite Verte in Yaounde, respectively; a district in Kingston Jamaica; African-Caribbeans living in central Manchester, UK. SUBJECTS: Aged 25-79 years, 61 from the Cameroonian urban site, 62 from the village site; 102 subjects from Jamaica (additional analysis on a subsample of 20): 29 subjects from Manchester, UK. MAIN OUTCOME MEASURES: Foods contributing to nutrients in each site to allow the development of a FFQ. RESULTS: A high response rate was obtained in each site. Comparison of macronutrient intakes between the sites showed that carbohydrate was the most important contributor to energy intake in Jamaica (55%) and the least in rural Cameroon. In rural Cameroon, fat (mainly palm oil) was the most important contributor to energy intake (44%). Manchester had the highest contribution of protein to energy (17%). Foods contributing to total energy, protein, fat and carbohydrate were determined. In rural Cameroon, the top 10 food items contributed 66% of the total energy intake compared to 37% for the top 10 foods in Manchester. Foods contributing to energy were similar in Jamaica and Manchester. Cassava contributed 44% of the carbohydrate intake in rural Cameroon and only 6% in urban Cameroon. One FFQ has been developed for use in both sites in Cameroon containing 76 food items. The FFQ for Jamaica contains 69 foods and for Manchester 108 food items. CONCLUSION: Considerable variations exist within sites (Cameroon) and between sites in foods which are important contributors to nutrient intakes. With careful exploration of eating habits it has been possible to develop standardized, but locally appropriate FFQs for use in African populations in different countries.

Adult↗
PubMed1996

Dependence of mutation induction on fast-neutron energy in a human epithelial teratocarcinoma cell line (P3).

To date, few studies have evaluated the magnitude of the risks of somatic effects in humans from low-dose or protracted radiation exposure to neutrons using in vitro or in vivo techniques (A. Kronenberg, Radiat. Res. 128, S87-S93, 1991). In earlier study a strong energy dependence was shown for neutron-induced mutations at both the hprt and the tk loci in a rodent fibroblast cell line (Zhu and Hill, Radiat. Res. 139, 300-306, 1994). Using fast neutrons produced by impinging protons on a beryllium target at the UCLA/VA cyclotron, we have been examining the energy dependence of mutation induction at the HPRT locus in a human epithelial cell line derived from solid tumor tissue. In the present study, human epithelial teratocarcinoma cells were exposed to neutron beams produced from protons with 46, 30, 20 and 14 MeV energy. We found that cytotoxicity increased by 50% as the neutron beams produced from 46 MeV to 14 MeV, confirming many earlier reports. But as with the Chinese hamster cells, the mutation frequency at the HPRT locus increased 2.5-4-fold with decreasing neutron energy. Additionally, although there was a strong energy dependence for mutation induction, we noted that the shape of the induction curves was curvilinear for the human cells compared to the linearity of the curves obtained for the Chinese hamster cells and some other non-solid tissue human cell lines. Calculations of the RBE, using gamma rays as the standard reflected these differences. The RBE for mutation at the HPRT locus was dependent not only upon energy but also on dose, giving rise to RBEs that were in some cases distinctly different from those found in the Chinese hamster cell line. In the low-dose region (doses below 75 cGy) the maximum RBE of about 5 resulted from irradiation by the lowest-energy neutron beam (14 MeV protons on beryllium).

Animals↗