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Biomedical subjects

A Singh

Publications and source records attributed to A Singh.

At least 55 records · Page 3Linked to original sources

Propagation of Chandipura virus in chick embryos.

Stocks of three Indian Chandipura virus (CHPV) isolates; one isolate from an adult febrile case in 1965 from Chandipura town, Maharashtra, and two isolates from two pediatric encephalitis cases from Andhra Pradesh, 2003 were inoculated in 10-day-old chick embryos by allantoic route. All three virus isolates replicated in chick embryos showing titre of log 10(12) to log 10(13) EID50. The results demonstrated that chick embryos are susceptible to CHPV and virus grows to high titres in this system. Therefore chick embryos can be used as an alternative host system for cultivation and isolation of CHPV as they are less expensive than laboratory animals and have several other advantages over cell cultures. Also this system can be used for the development of vaccine and diagnostic reagents.

Animals↗

Effect of dermal exposure to paraphenylenediamine and linear alkylbenzene sulphonate in guinea pigs.

OBJECTIVE: To study the effects of paraphenylenediamine (PPD) and linear alkylbenzene sulphonate (LAS) alone and in combination on the skin. METHODS: Forty-eight guinea pigs were divided equally into 4 groups and exposed to PPD (4 mg/kg), LAS (12 mg/kg) and PPD (4 mg/kg) plus LAS (12 mg/kg) for 30 days. The biochemical parameters such as acid phosphatase, gtutathione-s-transferase, glutathione peroxidase, glutathione, lipid peroxidation and histamine contents in exposed skin were estimated. The histopathological examination of the exposed skin was also carried out. RESULTS: The skin enzymes, lipid peroxidation, and histamine increased while glutathione decreased in skin. The simultaneously exposed group showed additive toxic effects. The histopathological examination showed severe hyperkeratosis, thickening of collagen fibres and vacuolisation of epidermal cells in PPD plus LAS exposed skin. CONCLUSION: The findings of the present study suggest that simultaneous exposure to PPD and LAS has additive toxic effects.

Acid Phosphatase↗

Stakeholder-based SWOT analysis for successful municipal solid waste management in Lucknow, India.

The present investigation is a case study of Lucknow, the main metropolis in Northern India, which succumbs to a major problem of municipal solid waste and its management. A qualitative investigation using strengths, weaknesses, opportunities and threats analysis (SWOT) has been successfully implemented through this community participation study. This qualitative investigation emphasizes the limited capabilities of the municipal corporation's resources to provide proper facilitation of the municipal solid waste management (MSWM) services without community participation in Lucknow city. The SWOT analysis was performed to formulate strategic action plans for MSWM in order to mobilize and utilize the community resources on the one hand and municipal corporation's resources on the other. It has allowed the introduction of a participatory approach for better collaboration between the community and municipal corporation in Lucknow (India). With this stakeholder-based SWOT analysis, efforts were made to explore the ways and means of converting the possible "threats" into "opportunities" and changing the "weaknesses" into "strengths" regarding a community-based MSWM programme. By this investigation, concrete strategic action plans were developed for both the community and municipal corporation to improve MSWM in Lucknow.

Cities↗

Opioid receptor involvement in food deprivation-induced feeding: evaluation of selective antagonist and antisense oligodeoxynucleotide probe effects in mice and rats.

Central administration of general and selective opioid receptor subtype antagonists in the rat has revealed a substantial role for mu, a moderate role for kappa, and a minimal role for delta receptors in the mediation of deprivation-induced feeding. Antisense probes directed against the kappa opioid receptor (KOP), nociceptin opioid receptor (NOP), and delta opioid receptor (DOP) genes in rats result in reductions similar to kappa and delta antagonists, whereas antisense probes directed against the mu opioid receptor (MOP) gene produced modest reductions relative to mu antagonists, suggesting that isoforms of the MOP gene may mediate deprivation-induced feeding. Since these isoforms were initially identified in mice, the present study compared the effects of general and selective opioid receptor antagonists on deprivation-induced feeding in rats and mice and antisense probes directed against exons of the MOP, DOP, KOP, and NOP genes on deprivation-induced feeding in the mouse. Food-deprived (12 and 24 h) rats and mice displayed similar profiles of reductions in deprivation-induced feeding following general, mu, and kappa opioid antagonists. In contrast, mice, but not rats, displayed reductions in deprivation-induced intake following delta antagonism as well as DOP antisense probes, suggesting a species-specific role for the delta receptor. Antisense probes directed against the KOP and NOP genes also reduced deprivation-induced intake in mice in a manner similar to kappa antagonism. However, the significant reductions in deprivation-induced feeding following antisense probes directed against either exons 2, 4, 7, 8, or 13 of the MOP gene were modest compared with mu antagonism, suggesting a role for multiple mu-mediated mechanisms.

Animals↗

Experimental verification of the mechanisms for nonlinear harmonic growth and suppression by harmonic injection in a traveling wave tube.

Understanding the generation and growth of nonlinear harmonic (and intermodulation) distortion in microwave amplifiers such as traveling wave tubes (TWTs), free electron lasers (FELs), and klystrons is of current research interest. Similar to FELs, the nonlinear harmonic growth rate scales with the harmonic number in TWTs. In klystrons, the wave number scaling applies to the nonlinear harmonic bunching and associated nonlinear space-charge waves. Using a custom-modified TWT that has sensors along the helix, we provide the first experimental confirmation of the scaling of nonlinear harmonic growth rate and wave number in TWTs. These scalings of a nonlinearly generated harmonic mode versus an injected linear harmonic mode imply that suppression by harmonic injection occurs at a single axial position that can be located as desired by changing the injected amplitude and phase.

Journal Article↗

Three-legged pair of pants anastomosis: a rare technique for renal transplantation.

Because of the shortage of donors, kidneys previously judged to be unsuitable are now accepted for transplantation. Successful engraftment of kidneys with multiple renal arteries is one of the challenges and requires meticulous vascular surgical technique. In one of our case of renal allograft with three renal arteries, we created a single lumen by suturing three arteries together, like a three-legged pair of pants. The end of the single lumen was anastomesed to the side of external iliac artery. There was brisk diuresis on table after transplantation. Postoperatively, the patient had an uneventful course and normal graft function.

Anastomosis, Surgical↗

Revegetating fly ash landfills with Prosopis juliflora L.: impact of different amendments and Rhizobium inoculation.

A revegetation trial was conducted to evaluate the feasibility of growing a legume species, Prosopis juliflora L., on fly ash ameliorated with combination of various organic amendments, blue-green algal biofertilizer and Rhizobium inoculation. Significant enhancements in plant biomass, photosynthetic pigments, protein content and in vivo nitrate reductase activity were found in the plants grown on ameliorated fly ash in comparison to the plants growing in unamended fly ash or garden soil. Higher growth was obtained in fly ash amended with blue-green algae (BGA) than farmyard manure or press mud (PM), a waste from sugar-processing industry, due to the greater contribution of plant nutrients, supply of fixed nitrogen and increased availability of phosphorus. Nodulation was suppressed in different amendments of fly ash with soil in a concentration-duration-dependent manner, but not with other amendments. Plants accumulated higher amounts of Fe, Mn, Cu, Zn and Cr in various fly ash amendments than in garden soil. Further, inoculation of the plant with a fly ash tolerant Rhizobium strain conferred tolerance for the plant to grow under fly ash stress conditions with more translocation of metals to the above ground parts. The results showed the potential of P. juliflora to grow in plantations on fly ash landfills and to reduce the metal contents of fly ash by bioaccumulation in its tissues.

Carbon↗

Cloning and nucleotide sequence of a novel cry gene from Bacillus thuringiensis.

A cry1Ab-type gene was cloned from a new isolate of Bacillus thuringiensis by PCR. When restriction pattern was compared with that of known genes it was found to have additional restriction site for ClaI. Nucleotide sequencing and homology search revealed that the toxin shared 95% homology with the known Cry1Ab proteins as compared to more than 98% homology among the other reported Cry1Ab toxins. The gene encoded a sequence of 1,177 amino acids compared to 1,155 amino acids encoded by all the other 16 cry1Ab genes reported so far. An additional stretch of 22 amino acids after the amino acid G793 in the new toxin sequence showed 100% homology with several other cry genes within cry1 family. Homology search indicated that the new cry1Ab-type gene might have resulted by nucleotide rearrangement between cry1Ab and cry1Aa/cry1Ac genes.

Bacillus thuringiensis↗

How menopause affects the lives of women in suburban Chandigarh, India.

OBJECTIVE: To ascertain the effect of menopause on the lives of women in suburban Chandigarh. METHOD: An integrated qualitative and quantitative study was performed in a low socioeconomic area of Chandigarh city, India. Women aged 40-60 years were enlisted and interviewed. RESULTS: Of the 725 enlisted women, 298 (41%) had attained menopause, 47 (6.5%) were in transition and 43 (5.9%) had undergone hysterectomy. The transition phase lasted for 1-12 months in 48.7% of cases and for 1 year or more in 20.8% of cases. No transitional changes were reported by 30.5% of women. A change in menstrual pattern was the hallmark of this phase and included delayed periods (37.6%), heavy bleeding (13%), scanty periods (7%) or a mixed pattern (11.7%). The majority of women interviewed (76%) did not experience any tension on attainment of menopause. Diminished acuity of vision was the most commonly reported menopausal symptom. Hot flushes were reported by 17.1% of women. Most women (94%) welcomed menopause. Use of hormone replacement therapy was not reported by anyone. CONCLUSION: Although north Indian women experienced various symptoms at menopause, they largely ignored these, while welcoming the freedom from menstruation-related worries.

Adult↗

Modulation of altered hepatic foci induction by diallyl sulphide in Wistar rats.

Diallyl sulphide (DAS) is a sulphur-containing volatile compound present in garlic (Allium sativum). It has been shown to inhibit a number of chemically induced forms of cancer in experimental animals. The present study demonstrates the inhibitory effect of DAS on the development of diethylnitrosamine (DEN) initiated and 2-acetyl-aminofluorene (2-AAF) promoted preneoplastic altered hepatic foci (AHF) in Wistar rats. AHF were scored and analysed by quantitative stereology using the Image Analysis system from frozen liver sections stained for biological markers, namely glutathione S-transferase, placental form (GST-P), gamma-glutamyl transpeptidase (GGT), adenosine triphosphatase (ATPase), glucose-6-phosphatase (G6 Pase) and alkaline phosphatase (AlkPase). DAS-supplemented rats were found to restore the near-normal levels of enzymes GST-P and GGT when exposed to DEN and 2-AAF. DAS administration following DEN and 2-AAF exposure led to the restoration of enzymic activity of ATPase, G6 Pase and AlkPase, as evident by number and area of the foci. These findings suggest the protective role of DAS in rat hepatocarcinogenesis, by suppressing DEN- and 2-AAF-induced AHF development.

Allyl Compounds↗

Visceral schistosomiasis of domestic animals in India: humoral immune status of infected cattle, sheep and goats against major polypeptide antigens of Schistosoma indicum and S. spindale.

Polypeptide profiles of Schistosoma indicum and S. spindale adult worm homogenates were obtained by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Humoral immune status of infected cattle, sheep and goats against Schistosoma indicum and S. spindale Ags was determined by immunoblot analysis and by indirect ELISA using four major polypeptides of approximate molecular masses 45 kDa, 40 kDa, 28 kDa and 15 kDa electro-eluted from the gel slices. Cattle sera samples had higher levels of antibodies against Si/s40 and Si/s28 than against Si/s45 antigen. Reasons have been discussed for the absence of detectable levels of anti-Si/s28, -Si/s45 and -Si/s40 antibodies in a significant number of sera samples from S. indicum egg-positive sheep.

Animals↗

Evaluation of expression of apoptosis-related proteins and their correlation with HPV, telomerase activity, and apoptotic index in cervical cancer.

OBJECTIVE: The aim of this study was to examine the expression of apoptosis-related proteins in cervical cancer, and investigate their correlation with the apoptotic index (AI), telomerase activity, human papilloma virus (HPV) infection and clinicopathological characteristics. METHODS: Fifty cervical cancer samples and 20 normal cervical tissues were assessed for the protein expression of survivin, Bcl-2, Cox-2, p53 and p73 by immunohistochemistry. HPV DNA was detected by PCR, telomerase activity by PCR-ELISA, and AI by TUNEL assay. RESULTS: 46/50 cervical tumors (92%) showed an increased telomerase activity as compared to 3/20 (15%) controls. 45/50 (90%) cervical tumors were positive for HPV, of which 30 were HPV-16 positive and 5 were HPV-18 positive. 24/50 (48%) tumors were positive for survivin, 14 (28%) for Bcl-2, 13 (26%) for Cox-2, 19/45 (42%) for p73, 10/45 (24%) for p53. Telomerase activity was highest in tumors with the poorest grade. A positive correlation was seen between survivin and Bcl-2, survivin and tumor stage, Bcl-2 and Cox-2, p73 and p53 and p73 and the AI. Despite the overexpression of various antiapoptotic proteins, no significant difference was observed in the AI between tumors and controls. CONCLUSIONS: Since deregulation of the apoptotic pathway appears to occur in cervical cancer, some apoptosis-related proteins could be assessed as potential markers for progression/prognosis in cervical cancer. Additionally, newer proteins such as p73 may play a compensatory role for the nonfunctional proteins such as p53.

Adult↗

Protective effect of bupropion on morphine tolerance and dependence in mice.

Possible reversal of morphine-induced tolerance and dependence by bupropion was studied in mice. A 10-day repeated injection regimen was followed to induce morphine tolerance and dependence. Bupropion (2 and 5 mg/kg) per se, when chronically administered for 9 days, failed to produce any significant change in tail-flick latency compared with the control mice. Chronic administration of bupropion (2 or 5 mg/kg) during the induction phase (days 1-9) delayed the development of tolerance to the antinociceptive action of morphine and also reversed naloxone- (2 mg/kg) precipitated withdrawal jumps. On the other hand, acute administration of bupropion (2 or 5 mg/kg) on day 10, i.e., during the expression phase of morphine dependence, reduced the incidence of naloxone-precipitated withdrawal jumps without affecting tolerance to the analgesic effect. In conclusion, results of the present study suggest the potential use of bupropion in tolerance and dependence.

Analgesics, Opioid↗