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Biomedical subjects

S Joshi

Publications and source records attributed to S Joshi.

At least 163 records · Page 9Linked to original sources
PubMed1992

Paranormal experiences in the general population.

The Dissociative Disorders Interview Schedule was administered to a random sample of 502 adults in the general population of Winnipeg, a midwestern Canadian city. Results showed that paranormal/extrasensory experiences were common in the general population. They were linked to a history of childhood trauma and to other dissociative symptom clusters. A factor analysis of the paranormal experiences identified three factors which together accounted for 44.0% of the combined variance of the scores. A model is proposed in which paranormal experiences are conceptualized as an aspect of normal dissociation. Like dissociation in general, paranormal experiences can be triggered by trauma, especially childhood physical or sexual abuse. Such experiences discriminate individuals with childhood trauma histories from those without at high levels of significance.

Acting Out↗
PubMed1992

Differential identification of Mycobacterium tuberculosis from various clinical specimens from Sassoon General Hospital, Pune.

A total of 619 clinical specimens from cases of pulmonary and extrapulmonary tuberculosis were processed by smear, culture and biochemical tests. Acid fast bacilli could be demonstrated in 93 samples (15.02%) by Z.N. staining method. Culture yielded positive growth in 95 samples (15.35%) M. tuberculosis human type was the most predominient pathogen obtained from 82 cultures (13.40%) M tuberculosis bovine type was isolated from 2 cases of ascitic fluids (0.32%). Atypical Mycobacteria were isolated from 11 samples (1.73%). 5 turned out to be M. scrofulacium, 4 were M. Kansasii, 1 was M. phlei and 1 was M. smegmatis.

Bacteriological Techniques↗
PubMed1992

Importance of periodic measurements in evaluating feeding programmes.

Attempts were made to show that periodic measurements are important for evaluating impact of feeding programmes as considerable "within variation" in increments exists which cannot be overlooked. From two socio-economic classes two kindergartens were selected one of which was implementing a feeding programme while the other was not. A total of 273 children were measured for weight and height, three times during the period of 7 months. Normal children showed significant gain in weight while malnourished children showed significant gain in height. The significance in weight (or height) increment at the end of the feeding programme did not necessarily mean that the significance could be obtained in each period even of equal time interval. Simple and cross correlations in increment revealed that weight increment in one period was significantly associated with height increment in the following period suggesting alternating priorities of the body for growth. Carefully planned longitudinal growth studies are therefore necessary for better understanding of growth process and thereby for proper evaluation of feeding programmes.

Body Height↗
PubMed1991

ATP synthase complex from bovine heart mitochondria: the oligomycin sensitivity conferring protein is essential for dicyclohexyl carbodiimide-sensitive ATPase.

The requirement of bovine heart mitochondrial oligomycin sensitivity conferring protein (OSCP) in conferring dicyclohexylcarbodiimide (DCCD)-sensitivity to membrane-bound F1 was investigated by using OSCP-depleted membrane fraction (UF0) of ATP synthase. The ATPase activity of UF0-F1 was completely insensitive to DCCD while that of UF0-F1-OSCP was inhibited 95% by 16 microM DCCD. Both UF0-F1 and UF0-F1-OSCP complexes bound 5 nmol [14C]DCCD/mg UF0, and all the radioactivity was found to be associated with the DCCD-binding proteolipid. The data suggest that OSCP may be necessary for transmitting not only energy-linked signals, but also signals induced by F0 inhibitory ligands in mitochondrial energy transduction.

Adenosine Triphosphatases↗
PubMed1991

Risk of cataract and history of severe diarrheal disease in southern India.

A case-control study was carried out in the state of Tamil Nadu, southern India, to examine the association between the risk of visually disabling cataract and a lifetime history of severe diarrhea (including cholera). A series of 421 subjects, aged 35 to 65 years, meeting case (n = 181) and control (n = 240) eligibility criteria were enrolled from 19 rural cataract-screening camps. Ninety case-control pairs were postmatched for (reported) age (+/- 2 years), sex, and area of residence. A history of diarrhea was obtained by using an algorithm developed by other investigators in India who have reported a strong association between cataract and diarrhea. An odds ratio of 0.8 (95% confidence limits: 0.0, 3.2) was obtained from matched pairs analysis, and an odds ratio of 1.3 (95% confidence limit: 0.6, 2.7) was obtained among all subjects (n = 392) from a logistic analysis that adjusted for age, sex, occupation, area of residence, and caste. Findings of this study do not support the hypothesis of an increased risk of visually disabling cataract in persons with a positive history of severe diarrhea.

Adult↗
PubMed1991

A putative approach for cloning 'silent' genes using retroviral vectors.

An alternative approach is described for cloning 'silent' or poorly expressed genes that might be activated as a result of proviral DNA integration. Generally, proviral DNA integrates randomly, in a single copy per cell, although some preferred integration sites exist. Thus, each cell infected by a retroviral vector should represent a different clone. These clones would have different phenotypes depending on the site of proviral DNA integration. Those expressing a desired phenotype would be screened for by using an assay system that depends on the gene of interest. The 5' and 3' flanking cellular DNA sequences, responsible for the observed phenotype in such mutants, could be cloned. Screening of these clones should be relatively simple due to the presence of a selectable marker in the proviral DNA. These sequences would then be used to isolate the wild type (wt) copy of the insertionally activated gene. Packaging retroviral vectors could lead to insertional activation of cellular genes and packaging of insertionally activated RNAs into vector particles. RNA extracted from the particles released into the culture medium would greatly facilitate cDNA cloning of 'silent' genes activated as a result of proviral DNA integration.

Animals↗
PubMed1991

Ranking of chemicals for carcinogenic potency--a comparative study of 13 carcinogenic chemicals and an examination of some of the issues involved.

A number of methods for categorization of carcinogens, including classification and ranking, have been examined and applied to 13 carcinogenic chemicals. Compounds known to be carcinogenic to humans ranked highly in the ranking systems. The TD50 approach was a satisfactory ranking system. The examination of the classification system of the International Agency for Research on Cancer, and the studies of the ranking systems revealed the importance of considering the underlying mechanisms of carcinogenesis. Some of the important problems of categorizing carcinogens are discussed.

Animals↗
PubMed1991

Inhibition of human immunodeficiency virus type 1 multiplication by antisense and sense RNA expression.

Human immunodeficiency virus type 1 (HIV-1) primarily infects CD4+ lymphocytes and macrophages and causes AIDS in humans. Retroviral vectors allowing neomycin phosphotransferase (npt) gene expression were engineered to express 5' sequences of HIV-1 RNA in the antisense or sense orientation and used to transform the human CD4+ lymphocyte-derived MT4 cell line. Cells expressing antisense or sense RNA to the HIV-1 tat mRNA leader sequence, as part of the 3' untranslated region of the npt mRNA, remained sensitive to HIV-1 infection. In contrast, resistance to HIV-1 infection was observed in cells expressing antisense RNA to the HIV-1 primer-binding site or to the region 5' to the primer-binding site as part of the 3' region of the npt mRNA. Cells expressing the tat mRNA leader sequence in the sense orientation as a precise replacement of the 5' untranslated region of npt mRNA were also resistant to HIV-1. These results indicate that sense and antisense approaches can be used to interfere with HIV-1 multiplication.

Base Sequence↗
PubMed1991

Resistance to human immunodeficiency virus type 1 (HIV-1) infection in human CD4+ lymphocyte-derived cell lines conferred by using retroviral vectors expressing an HIV-1 RNA-specific ribozyme.

Toward gene therapy for the treatment of human immunodeficiency virus type 1 (HIV-1) infections in AIDS, Moloney murine leukemia virus-derived retroviral vectors were engineered to allow constitutive and tat-inducible expression of an HIV-1 5' leader sequence-specific ribozyme (Rz1). These vectors were used to infect the human CD4+ lymphocyte-derived MT4 cell line. The stable MT4 transformants expressing an HIV-1 RNA-specific ribozyme, under the control of the herpes simplex virus thymidine kinase (tk) promoter, were found to be somewhat resistant to HIV-1 infection as virus production was delayed. In cells allowing ribozyme expression under control of the simian virus 40 or cytomegalovirus promoter, the rate of HIV-1 multiplication was slightly decreased, and virus production was delayed by about 14 days. The highest level of resistance to HIV-1 infection was observed in MT4 cells transformed with a vector containing a fusion tk-TAR (trans activation-responsive) promoter to allow ribozyme expression in a constitutive and tat-inducible manner; no HIV-1 production was observed 22 days after infection of these cells. These results indicate that retroviral vectors expressing HIV-1 RNA-specific ribozymes can be used to confer resistance to HIV-1 infection.

Base Sequence↗
PubMed1991

Dissociative experiences in the general population: a factor analysis.

The 28-item Dissociative Experiences Scale was administered to a stratified cluster sample of 1,055 respondents in the general population of Winnipeg. Dissociative experiences were common in the sample and were not related to socioeconomic status, sex, education, religion, or place of birth, although they declined with age in both sexes. A principal components analysis identified three factors accounting for 47.1 percent of the combined variance of the scores. The first factor, absorption-imaginative involvement, is composed of common, benign experiences, such as missing part of a conversation and being able to ignore pain. The other two factors, activities of dissociated states and depersonalization-derealization, composed of less common experiences such as not recognizing friends or family members and not recognizing one's reflection in a mirror, may be powerful predictors of DSM-III-R dissociative disorders.

Adult↗
PubMed1991

Pulmonary complications of upper abdominal surgery.

Pulmonary complications encountered in 67 patients undergoing upper abdominal surgery in our unit in one year period are analysed. Pulmonary function tests and their post-operative reduction, as also the risk factors are discussed. Pathophysiology responsible for pulmonary complications is outlined.

Adolescent↗
PubMed1991

Microbiological study of breast milk with special reference to its storage in milk bank.

Sixty five breast milk samples were subjected to bacteriological studies; each sample thrice (in fresh state, after heating at 1000C and freezing for 5 days at -20 degrees C). In fresh State, Staphylococci and diphtheroids were predominant organisms. After heating, none of the samples showed any micro-organisms while after freezing for 5 days, all the samples showing presence of micro-organisms earlier, showed decrease in colony counts. None of the milk samples showed inclusions of cytomegalovirus. Serum samples of mothers tested for Hepatitis B surface antigen and human immunodeficiency virus antibodies gave negative results. Such studies i.e. screening of breast milk samples are important if human milk is to be stored in banks and supplied to premature (high risk group) children.

Bacteria↗
PubMed1990

ATP synthase complex from bovine heart mitochondria. Subunit arrangement as revealed by nearest neighbor analysis and susceptibility to trypsin.

The nearest neighbor relationships of bovine mitochondrial H(+)-ATPase subunits were investigated by the chemical cross-linking approach using the homobifunctional cleavable reagents dithiobis(succinimidyl propionate) and disuccinimidyl tartrate. Cross-linked proteins were resolved by one- and two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Individual subunits were detected by silver staining or by Western blotting and staining with subunit-specific antisera. Products larger than 80,000 daltons were not analyzed. Interactions between F1 subunits included cross-links between gamma and delta as well as gamma and epsilon subunits. Among F0 subunit interactions were observed cross-links of (i) coupling factor 6 (F6) with 8-, 20-, and 24-kDa proteins, (ii) oligomycin sensitivity-conferring protein (OSCP) with 24-kDa protein, and (iii) 20-kDa protein with 24-kDa protein. In addition, several cross-links among subunits involving F1 and F0 sectors were detected. These included cross-links between F6 and alpha, F6 and gamma, OSCP and alpha/beta, and 24-kDa protein and alpha/beta. Thus, OSCP, F6, and the 24-kDa protein were found to form cross-links with both F1 and F0 subunits. The surface accessibility of F0 subunits was investigated by subjecting aliquots of F0 to trypsin treatment. Our data demonstrated that the rate of degradation was in the order OSCP greater than 24-kDa protein greater than or equal to F6 greater than subunit 6. The degradation of subunits of F0 was prevented in intact or reconstituted F1-F0. Based on our present and previously published observations, a model of H(+)-ATPase has been proposed wherein OSCP, F6, and the 24-kDa protein are placed in the stalk region and the alpha and beta subunits of F1-ATPase have been extended down to the membrane surface to enclose the stalk segment.

Adenosine Triphosphatases↗
PubMed1990

Efficient replication, integration, and packaging of retroviral vectors with modified long terminal repeats containing the packaging signal.

Retroviral vectors were modified to contain packaging (psi) signals of varying lengths (nucleotides 211-355, 211-565, or 211-1039 of MoMuLV RNA) between the U3-r and U5 sequences of their 5' long terminal repeat (LTR). For the vector MoTN-PR3, containing the full length 211-1039 nucleotide-long psi signal within the 5' LTR, replication, integration, and packaging were almost as efficient as for the original unmodified vector. This result confirmed that the 211-1039 nucleotide-long sequence from the MoMuLV RNA is sufficient and necessary to allow efficient packaging of RNAs. In addition, an important site was revealed where insertion of foreign DNA sequences of up to 829 nucleotides can be made within the 5' LTR, between U3-r and U5 sequences, without affecting viral replication, integration, or packaging.

Animals↗
PubMed1990

ATP synthase complex from bovine heart mitochondria. Passive H+ conduction through F0 does not require oligomycin sensitivity-conferring protein.

Oligomycin sensitivity-conferring protein (OSCP) is a water-soluble subunit of bovine heart mitochondrial H(+)-ATPase (F1-F0). In order to investigate the requirement of OSCP for passive proton conductance through mitochondrial F0, OSCP-depleted membrane preparations were obtained by extracting purified F1-F0 complexes with 4.0 M urea. The residual complexes, referred to as UF0, were found to be deficient with respect to OSCP, as well as alpha, beta, and gamma subunits of F1-ATPase, but had a full complement of coupling factor 6 as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting techniques. These UF0 complexes had no intrinsic ATPase activity and were able to bind nearly the same amount of F1-ATPase in the presence of either OSCP or NH4+ ions alone, or a combination of the two. However, the preparations exhibited an absolute dependency on OSCP for conferral of oligomycin sensitivity to membrane-bound ATPase. The passive proton conductance in UF0 proteoliposomes was measured by time-resolved quenching of 9-amino-6-chloro-2-methoxyacridine or 9-aminoacridine fluorescence following a valinomycin-induced K(+)-diffusion potential. The data clearly establish that OSCP is not a necessary component of the F0 proton channel nor is its presence required for conductance blockage by the inhibitors oligomycin or dicyclohexylcarbodiimide. Furthermore, OSCP does not prevent or block passive H+ leakage. Comparisons of OSCP with the F1-F0 subunits from Escherichia coli and chloroplast lead us to suggest that mitochondrial OSCP is, both structurally and functionally, a hybrid between the beta and delta subunits of the prokaryotic systems.

Adenosine Triphosphatases↗
PubMed1990

An insulin-like compound consisting of the B-chain of bovine insulin and an A-chain corresponding to a modified A- and the D-domains of human insulin-like growth factor I.

We report the synthesis and biological evaluation of a two-chain, disulfide-linked, insulin-like compound consisting of the B-chain of bovine insulin and an A-chain corresponding to the A- and D- domains of human insulin-like growth factor-I (IGF-I) in which the A-domain amino-acid residues -Phe49-Arg50-Ser51-found in IGF-I have been replaced by -Ala-Gly-Val-, the homologous region of sheep insulin. The compound is indistinguishable from a previously reported compound whose A-chain corresponds to the A- and D-domains of IGF-I without the substitution, in assays for insulin-like activity as well as in assays for growth-promoting activity. We conclude that these A-domain residues do not contribute significantly to the interaction of IGF-I with either insulin or IGF-I receptors.

Amino Acid Sequence↗