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Biomedical subjects

G Banerjee

Publications and source records attributed to G Banerjee.

At least 19 recordsLinked to original sources
PubMed2004

Role of keratinocytes in antigen presentation and polarization of human T lymphocytes.

Allergic contact dermatitis is a T-cell-mediated inflammatory skin disease in which interaction between skin keratinocytes and migrating T lymphocytes may play a critical part. In this study, the role of keratinocytes as allergen-/antigen-presenting cells (APCs) leading to activation of T lymphocytes is investigated using a human epidermal cell line A431. It is known that cultured cells do not express human leucocyte antigen (HLA) and hence can be used as APCs independent of HLA profile of both APCs and T cells from human volunteers. This cell line responded to common allergens and irritants by inducing or upregulating the cell-surface expression of HLA-DR, and intercellular adhesion molecule-1 and B7 mRNA transcripts in keratinocytes. In addition, allergen-primed A431 cells also induced allergen-specific proliferation of human T lymphocytes in cocultures. Anti-HLA-DR, interleukin-1alpha (IL-1alpha) antibodies and lysosomotropic agent chloroquine inhibited the proliferation. Allergens also upregulated cytokines IL-1alpha, granulocyte-macrophage colony-stimulating factor, Gro-alpha and IL-12 in keratinocytes. Further, keratinocytes activated by allergens induced polarization of activated T lymphocytes to the Th1 phenotype.

Antigen Presentation↗
PubMed2002

Role of different valence states of chromium in the elicitation of allergic contact dermatitis.

Chromium, a known contact sensitizer, is present at high levels in certain detergent bars (40-50 p.p.m.) sold in India. A concern was whether chromium present in such detergent bars could sensitize users or their use lead to the elicitation of allergic contact dermatitis. Chromium present in detergent bars was analyzed for its valence state. It was found to be trivalent [Cr (III)] and not hexavalent [Cr (VI)]. An elicitation test on normal volunteers, as well as on volunteers who were sensitive to chromium, was carried out to determine the elicitation potential of chromium (III) in the bars. Of the 48 volunteers who completed the study, 30 did not show any positive response to either potassium dichromate, the positive control, or the detergent bar containing chromium (III). 18 volunteers who were identified as chromium-sensitive showed a positive response to potassium dichromate but not to the detergent bar containing trivalent chromium. This study clearly showed that the detergent bar with 40-50 p.p.m. of trivalent chromium did not elicit any allergic contact dermatitis even in individuals known to be chromium-sensitive. Hexavalent chromium (potassium dichromate) did however, elicit allergic contact dermatitis in these subjects.

Chromium↗
PubMed2002

Alopecia universalis in a case of systemic lupus erythematosus.

We report a case of systemic lupus erythematosus (SLE) who presented with alopecia universalis. MR, a 23 years female patient was admitted with alopecia universalis and other features of SLE like peripheral arthritis, fever, nephritis, butterfly rash over the malar regions, positive ANA and anti-ds DNA antibodies. There was a gap of four years between the onset of alopecia universalis and other clinical features of SLE. The alopecia was of non-scarry variety and responded to systemic and topical steroids.

Adult↗
PubMed2002

In vitro regeneration of roots of Phyla nodiflora and Leptadenia reticulata, and comparison of roots from cultured and natural plants for secondary metabolites.

Adventitious roots, generated using leaf explants of P. nodiflora, and meristem explants of L. reticulata, were cultured on Murashige and Skoog (MS) medium supplemented with napthylacetic acid (2 microM) and indole butyric acid (3 microM) respectively. After 30 days, subculturing of roots in liquid MS medium with napthylacetic acid (1.5 microM) for P. nodiflora and indole butyric acid (3 microM) for L. reticulata afforded considerable increase in root mass. HPTLC profiles and microscopic examination of transverse sections of in vitro and naturally grown roots provided information on secondary metabolite accumulation vis-à-vis developmental stages of the root.

Animals↗
PubMed2002

Pesticide (acephate) removal by GAC: a case study.

Pesticides are persistent pollutants which need utmost attention in agricultural pollution. They usually accumulate in the food chain, and hence are hazardous in nature. The present study reports the performance of granular activated carbon (GAC) in the removal of acephate contained in the effluent of a nearby pesticide manufacturing industry. In the batch study, the optimum dose of GAC was found to be 85 gm/litre for almost 100% removal of acephate from its initial concentration of 2.9 mg/litre which was found in the industrial effluent under treatment. The adsorption kinetics were represented closely by Langmuir isotherm. The equilibrium time was found as 80 minutes. The adsorptive capacity of GAC for acephate (pesticide) was of the order of 0.04614 mg/gm. A column system was devised and designed based on bed depth-service time (BDST) approach with the experimental value of 'a' and 'b' as 6.125 and 47.75 respectively.

Adsorption↗
PubMed2001

Salp25D, an Ixodes scapularis antioxidant, is 1 of 14 immunodominant antigens in engorged tick salivary glands.

Rabbits or guinea pigs infested with Ixodes scapularis acquire resistance to tick bites, a phenomenon, known as tick immunity, that is partially mediated by antibody. To determine the salivary gland antigens that elicit antibodies in the host, an I. scapularis salivary gland cDNA expression library was probed with serum from tick-immune rabbits. Sera from sensitized rabbits strongly recognized 47 of 100,000 library clones in an antibody-screening assay. These 47 clones encoded 14 different I. scapularis genes, including a glutathione peroxidase homologue. Expression of these 14 genes in engorged tick salivary glands was confirmed by reverse-transcription polymerase chain reaction. The I. scapularis glutathione peroxidase homologue, named salp25D, was expressed in both unfed and fed nymphal salivary glands. Recombinant Salp25D was able to catalyze the reduction of hydrogen peroxide in the presence of reduced glutathione and glutathione reductase. These results categorize the prominent salivary gland proteins in I. scapularis and demonstrate the presence of a potent antioxidant in tick saliva.

Amino Acid Sequence↗
PubMed2000

Psychiatric morbidity of a rural Indian community. Changes over a 20-year interval.

BACKGROUND: Cross-sectional studies give no indication of the changes that may occur in the mental health status of a community in course of times. Studies should be designed to assess these changes. AIMS: To assess the changes, if any, in the prevalence of mental disorders in a rural community after an interval of 20 years in the context of its changing socio-economic conditions. METHOD: A door-to-door survey of the prevalence of psychiatric morbidity in two villages was conducted by a team of psychiatrists. The survey was repeated after 20 years by the same team and by the same method. Changes in the mental health status of the community were compared. RESULTS: Total morbidity per 1000 fell from 116.8 to 105.2. Morbidity in men fell from 86.9 to 73.5 per 1000 and in women from 146.8 to 138.3 per 1000. Rates of anxiety, hysteria and phobia had fallen dramatically and those of depression and mania had risen significantly. CONCLUSION: The level of psychiatric morbidity showed no statistically significant change. The morbidity pattern (relative proportion of type of morbidity), however, showed some interesting changes. Similar studies should be done on a larger sample.

Adolescent↗
PubMed1998

Comparison of the cardiovascular effects of 2.5% phenylephrine and 10% phenylephrine during ophthalmic surgery.

PURPOSE: The recommended concentration of topical phenylephrine for mydriasis is still a matter of debate. Our purpose was to compare the cardiovascular effects of 10% and 2.5% topical aqueous phenylephrine. METHODS: We carried out a double-masked randomised study on 54 consecutive patients undergoing routine local anaesthetic cataract extraction, comparing the effects on blood pressure and heart rate of either 2.5% or 10% topical aqueous phenylephrine in combination with 1% topical aqueous tropicamide in those with no history of cardiovascular disease. RESULTS: No difference was found in the rise in blood pressure produced by 2.5% and 10% topical aqueous phenylephrine. We also found no sustained changes in blood pressure or heart rate after instillation of either 2.5% or 10% topical aqueous phenylephrine. CONCLUSION: We recommend the routine use of 2.5% topical aqueous phenylephrine as a mydriatic agent during cataract surgery and acknowledge the role of 10% topical aqueous phenylephrine as an effective mydriatic agent in cases where 2.5% phenylephrine may not be so effective, such as in subjects with darkly pigmented irides.

Aged↗
PubMed1998

A novel peptide-grafted liposomal delivery system targeted to macrophages.

The interaction of chemotactic peptide (e.g., fMet-Leu-Phe)-grafted liposomes with macrophages is noted to be rapid and specific. At a grafted peptide concentration of 100 nmol, internalization of the peptide-grafted liposomes by the macrophages is found to reach equilibrium in 30 min. The peptide alone and the peptide-grafted empty liposomes are found to show moderate antileishmanial activity in vitro. Primaquine, which is known to generate O2- in phagocytic cells, showed leishmanicidal properties when it was tested in vitro against parasite-infected macrophages over a certain range of concentrations. It showed much better efficacy against experimental leishmaniasis when it was used in the fMet-Leu-Phe-grafted liposomal form in comparison with its efficacy when it was either in the free form or encapsulated in ungrafted liposomes. The conventional toxicity parameters (e.g., blood pathology and tissue histology-specific enzyme levels related to normal liver function) are found to be very close to normal when fMet-Leu-Phe-grafted liposomal primaquine is used. The biodegradabilities of both the drug and the delivery systems are also found to be very satisfactory. Thus, this delivery system may have possible applications for the treatment of leishmaniasis as well as other macrophage-associated disorders.

Animals↗
PubMed1997

A study on transferable R-plasmids among Shigella species at Lucknow.

A total of 500 Shigella strains were included in the present study out of which 233 were isolated at National Shigella Centre of Postgraduate Department of Microbiology, K.G. Medical College, Lucknow during last 5 years and 267 strains were received from different parts of the country. Predominent serotypes were Sheigella flexneri 292 (48.4%) followed by Shigella dysenteriae 153 (30.6%), Shigella boydii 32 (6.4%) and Shigella sonnei 23 (4.6%). All the strains were sensitive to Nalidix acid, Gentamycin, Kanamycin, Neomycin and Furazolidine. Varying degree of resistance was shown to Streptomycin, Chloramphenicol, Tetracycline and Ampicillin. R. plasmid extraction was done and transfer was studied on E. Coli K-12.

Drug Resistance, Microbial↗
PubMed1996

Drug delivery system: targeting of pentamidines to specific sites using sugar grafted liposomes.

Different sugar-grafted liposomes were prepared and tested against experimental leishmaniasis in vivo using the classical drug pentamidine isethionate and its methoxy derivative. Both the drugs, when encapsulated in sugar-grafted liposomes were found to be more potent in comparison to normal liposome-encapsulated drug or to the free drug. Moreover, the mannose-grafted liposomes were adjudged to be the best in lowering of spleen parasite load in comparison with those bearing glucose or galactose. When encapsulated in mannose-grafted liposomes the therapeutic efficacy of pentamidine isethionate was found to be better than that of its methoxy derivative, although the latter seemed to be less toxic than the pentamidine isethionate itself.

Alanine Transaminase↗
PubMed1996

Spontaneous perforation of the ureter: endourological management with renal preservation.

Spontaneous perforation of the ureter proximal to an obstruction has not been well described in the literature. We present a rare case of spontaneous perforation of the ureter, proximal to a radiolucent upper ureteric stone, in a 58-year-old diabetic female, causing a large infected urinoma and septicaemia in a solitary functioning kidney. The diagnosis was confirmed by computer tomography scan. We managed the case successfully by endourology only. The case emphasizes the importance of the differential diagnosis in a diabetic patient with obstructive uropathy.

Female↗
PubMed1996

Nosocomial infection due to enterobacter cloacae in a tertiary care hospital in northern India.

A total of 151 Enterobacter cloacae strains isolated from clinical samples (n = 139) and the hospital environment (n = 12) at a tertiary care hospital in northern India during January to October 1993, were analysed. The maximum isolations were during May (n = 24), June (n = 23) and July (n = 22). Urinary tract infection (n = 56) was the most common complication of E. cloacea infection followed by wound infection (42), respiratory tract infection (23) and bacteraemia/septicaemia (18). The frequency of resistance to different drugs was ampicillin 77.4 per cent, cotrimoxazole 79.5 per cent, gentamicin 57.5 per cent, cefotaxime 47 per cent and ofloxacin 36 per cent. Sixty three (41.7%) strains exhibited resistance to multiple drugs. Environmental isolates from bed, hospital diet, hand swab and water from a leaking drain pipe in a ward showed the same resistance pattern. A single index strain could not be identified using phage and biotyping, indicating that a variety of strains were responsible for the nosocomial infection. Adoption of strict aseptic measures and repair of the pipe brought down the infection rate.

Bacterial Typing Techniques↗
PubMed1995

Determinants of help-seeking behaviour in cases of epilepsy attending a teaching hospital in India: an indigenous explanatory model.

Psychosocial factors determining the choice of health facility in 30 cases of epilepsy attending the psychiatric outpatient department (OPD) of a teaching (referral) hospital in India were studied. The majority of those who chose indigenous healers as their first contact treatment facility did so on the decision of the family. A belief in the supernatural causation of epilepsy combined with family decision was associated with the choice of indigenous health facility. Belief in the physical cause of epilepsy and the participation of social network in decision making were, on the other hand, closely associated with the choice of practitioners of modern medicine. The time-lag between onset of illness and first contact for treatment was short when indigenous healers were consulted first, however these patients usually took a long time to reach the referral centre when they passed through the indigenous healers.

Adolescent↗