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M Bose

Publications and source records attributed to M Bose.

At least 19 recordsLinked to original sources
PubMed1998

Aflatoxin B1-induced micronuclei and cell cycle alterations in lung and bone marrow cells and their modulation by Piper argyrophyllum extract.

Aflatoxin B, (AFB1) is a clastogen that causes cellular damage by covalent modification of nucleic acids. In this investigation, male rats were injected i.p. with AFB1 (8 mg/kg b.w.) in DMSO and the same dose of AFB1 was also administered intratracheally (i.t.) to the animals separately. The animals were killed after 26 h of the carcinogen treatment, femur bone was removed, and bone marrow cells were isolated and stained with Mayer's hematoxylin and eosin. Micronuclei (Mn) were scored by using light microscopy. Bronchoalveolar lavage (BAL) was prepared from rats administered AFB1 i.t. A part of BAL was fixed with 70% ethanol, stained with the fluorochrome DAPI, and analysed for cell cycle variations; the other part of the lavage was used for making slides to record Mn with a fluorescent microscope. A significantly greater proportion of lung cells were found to enter cell cycle with extended S-phase due to AFB1 treatment. Mn were induced in polychromatic erythrocytes (PCE) as compared to normochromatic erythrocytes (NCE) in the bone marrow of AFB1-treated rats, where there was nearly a three-fold increase in the number of Mn of bone marrow cells. The administration of AFB1 resulted in a two-fold rise in the Mn in the lung cells. The effect of BSO, DEM, and PB, the modulators of AFB1 metabolism, was studied on AFB1-induced Mn formation. A significant increase in the Mn score in PCEs of BSO- and DEM-treated rats was noted, while a slight reduction in the Mn score was noted in the case of PB-treated rats. The administration of the methanol extract of the leaves of Piper argyrophyllum (taken up in DMSO) to rats for a week exhibited normalising effect on AFB1-induced Mn in bone marrow cells. These observations record the induction of Mn in lung cells due to AFB1 for the first time. We propose the utility of AFB1-induced Mn as a model for screening plant extracts as inhibitors of genotoxicity. Prevention of genotoxic changes described above by phytochemicals is being pursued in our Laboratories.

Aflatoxin B1↗
PubMed1997

Sterilization of slide sheath anesthetic injection systems placed within sharps containers.

The purpose of this study was to evaluate the effect that two steam autoclaves and an unsaturated chemical vapor sterilizer had on killing bacterial endospores present on commercial spore strips or applied to sterile anesthetic injection systems placed within sharps containers. Three types of sterilizers were used: a gravity steam autoclave, a high vacuum steam autoclave and an unsaturated chemical vapor sterilizer. The microbial challenge for the sterilizers were Bacillus stearothermophilus spores present on commercial spore strips or drawn into and applied onto sliding sheath anesthetic injection systems with anesthetic carpules attached. Spore-soiled items were placed into the middle of sharps containers three-quarters-filled with representative clinical waste and sterilized. If, after culturing, sterilization of all test items in a group was not achieved, additional sterilization time was applied. Spore strips were killed within a single cycle of each sterilizer. Spore-soiled injection systems and carpules could not be routinely sterilized in the gravity steam autoclave or unsaturated chemical vapor sterilizers, even after three consecutive sterilization cycles. These items, however, were sterilized by exposure to a single-treatment cycle in a high-vacuum steam autoclave. Results indicate that routine sterilization of spore contaminated anesthetic carpules or injection systems could not be accomplished in a reasonable amount of time using sterilizers commonly found in dental offices.

Anesthesia, Dental↗
PubMed1996

Purification, microsequencing, and immunolocalization of p36, a new interferon-alpha-induced protein that is associated with human lupus inclusions.

The trace interferon-alpha-induced protein, p36, was induced in Raji cells in association with lupus inclusions. It was solubilized in a nonionic detergent buffer, enriched by differential centrifugation and by preparative isoelectric focusing, and purified to homogeneity on two-dimensional protein gels. Failure to obtain N-terminal amino acid sequence, however, suggested a blocked alpha-amino group. Sequences of six tryptic peptides, 13-19 amino acids in length, were obtained after digestion, microbore-high performance liquid chromotography purification, and chemical sequence analysis. None of the six sequences, which represented approximately 25% of the entire protein, shared any meaningful homologies with entries in protein sequence repositories. Raji-cell p36 was shown in Western blots with antipeptide antibodies to be induced at least 400-fold and by immunofluorescence microscopy to co-localize with the endoplasmic reticulum resident protein, protein disulfide isomerase. These results show that p36 is a new interferon-alpha-induced protein that localizes in the endoplasmic reticulum, the cell region in which the lupus inclusions form, and that p36 is probably physically associated with the lupus inclusions.

Amino Acid Sequence↗
PubMed1995

Proinflammatory cytokines can significantly induce human mononuclear phagocytes to produce nitric oxide by a cell maturation-dependent process.

The capacity of three proinflammatory cytokines, interferon-gamma (rhifn-gamma), tumour-necrosis factor-alpha (rHTNF-alpha) and interleukin-1 (rHIL-1), to induce release of nitric oxide (NO) from human mononuclear phagocytes were investigated. Peripheral blood monocytes were either used immediately or after culturing in vitro to develop into monocyte-derived macrophages (macrophages). Lipopolysaccharide (LPS) was used as second signal in all experiments. The three cytokines tested had significantly high enhancing influence on the production of nitric oxide by monocytes as well as by macrophages. However production was significantly higher by the monocytes matured in vitro to macrophages (P < 0.01). In our experimental system LPS had only marginal synergistic influence on production of NO2, and IFN-gamma demonstrated to be the most efficient of the three cytokines tested. Addition of L-arginine in the monocytes/macrophages culture further amplified production of NO2, whereas addition of NG-monomethylarginine abrogated this amplification. We conclude that human mononuclear phagocytes are capable of using inducible nitric oxide synthase pathway to produce nitric oxide.

Arginine↗
PubMed1995

Dysregulation of homeostasis of blood T-lymphocyte subpopulations persists in chronic multibacillary pulmonary tuberculosis patients refractory to treatment.

DESIGN: The dysregulation of homeostasis of blood-T lymphocyte subpopulations was studied in 21 cases of chronic, multibacillary pulmonary tuberculosis refractory to treatment. The clinico-bacteriological and immunological parameters studied in these cases (Gr A) were compared with those of a group of 10 newly-diagnosed drug sensitive cases of pulmonary tuberculosis (Gr B) at the beginning of the study and after 3 months of chemotherapy for tuberculosis. The chronic cases were treated with drugs selected from a reserve line. 10 normal healthy individuals were included in this study as a control group. RESULTS: At the beginning of the study the mean CD4/CD8 lymphocyte ratios in the refractory cases (0.69) and the newly diagnosed cases (0.81) were significantly lower than those of the normal control subjects (1.84). After 3 months of chemotherapy all but 3 of the newly-diagnosed cases showed clinical improvement, and all became sputum-negative. Their CD4/CD8 ratio recorded a rise to near normal (1.54). On the contrary, following 3 months of reserve-line regimen, only 7 of the 21 group A cases showed sputum conversion. In all of the refractory cases, irrespective of sputum conversion, the CD4/CD8 ratio remained low (1.05). CONCLUSION: This probably indicates that due to a long-standing bacillary load in drug resistant pulmonary tuberculosis patients the dysregulation of homeostasis of blood-T lymphocytes becomes persistent. This in turn delays their clinical and immunological recovery, even when therapy is adequate.

Adolescent↗
PubMed1994

Histobiochemical changes in lung of protein deficient rats following repeated exposures of MIC vapour.

Adult male albino rats, maintained on normal or protein deficient diets from weanling, were exposed to repeated doses of MIC vapour (0.32 mg/L for 8 min for 5 consecutive days) under static conditions. Histopathology and the activities of alkaline and acid phosphatases and GSH content of lung were studied upto day 14 after exposure. Mild but repeated exposures of MIC vapour caused severe pulmonary lesions like denudation of bronchiolar epithelial lining tissue, cellular infiltration, edema, emphysema followed by hyperplasia, hypertrophy, fibrosis and intraluminal fibroplasia. The activities of alkaline and acid phosphatases were increased at earlier intervals while GSH content decreased significantly and remained low throughout the experimental duration. Protein deficiency was found to aggravate the toxic potentials of MIC in present condition.

Acid Phosphatase↗
PubMed1993

Immunohistopathological spectrum in cutaneous tuberculosis.

Granulomas of lupus vulgaris were characterized by a raised CD4+/CD8+ ratio, while in scrofuloderma this was significantly decreased. Tuberculosis verrucosa cutis showed intermediate changes. These immunological variations suggest that cutaneous tuberculosis forms a spectrum with strong cell-mediated immunity seen in lupus vulgaris, and weaker cell-mediated responses in scrofuloderma; tuberculosis verrucosa cutis is intermediate between the two.

Antigens, CD↗
PubMed1992

Very low calorie diets and pre-fasting prolonged QT interval. A hidden potential danger.

The association of torsade de pointes and a prolonged electrocardiographic QT interval is well described. A prolonged QT interval may be congenital or acquired in several ways--by the use of anti-arrhythmic agents exemplified by quinidine, by the presence of hypocalcaemia or hypokalaemia, by the use of psychotropic drugs, and by the presence of intrinsic cardiac disease or bradycardias. Possibly less well appreciated is the potential for drastic weight loss to prolong the QT interval, as the present case report illustrates. A young woman weighing 244 pounds lost 24 pounds in two weeks with a consequent prolongation of QTc interval from pre-diet value of 0.57 seconds to 0.72 seconds at admission, when severely symptomatic paroxysms of torsade de pointes were recorded. Successful therapy with lignocaine and prompt re-feeding suppressed the arrhythmia and, three days later, the QTc was reduced to almost its pre-diet state. A (UK) DHSS report offers guidelines in the use of very low calorie diets. This case suggests that a pre-diet electrocardiogram should be carefully assessed for QT prolongation before initiation of dieting to achieve serious weight loss.

Adolescent↗
PubMed1992

Inhalation toxicity of methylisocyanate: assessment of germ cell mutagenicity and reproductive effects in rats.

Adult male Wistar rats were exposed to methylisocyanate (MIC, 3.2 mg/l, single inhalation exposure for 8 min under static condition) or ethyl methanesulphonate (EMS, 150 mg/kg, single ip dose) for the assessment of germ cell mutagenicity and reproductive effects. Sequential matings of treated males with normal females on days 1-7, 8-14 and 15-21 post-exposure did not indicate any induction of dominant lethal mutation (increased frequency of preimplantation losses and early fetal deaths) by MIC but it was significantly induced by EMS as compared to respective controls. Males, necropsied after 21 days of exposure, showed no effect of MIC on epididymal sperm density and morphology. EMS also had no effect on sperm density but it significantly induced morphological abnormalities in sperm as compared to untreated controls. There was an acute and transitional reduction in reproductive performance (10-21%) of MIC-exposed males during days 1-14 post-exposure followed by recovery to the normal level during days 15-21 post-exposure. The progeny of MIC-exposed males was also normal in terms of litter size, litter weight, neonatal survival and body weight gain in litters up to 10 days post-partem. It is concluded with the evidence at hand that the observed failure of MIC to cause germ cell mutagenicity is related to its poor biodistribution to the target site(s) and a transient reduction in the reproductive performance of MIC-exposed males is a result of general stress and disconsolate copulation.

Administration, Inhalation↗
PubMed1991

[Paresthesias].

A 23-year-old patient suddenly experienced paresthesia in both legs which progressively ascended to the region of the umbilicus and finally also occurred in all fingers. The physical examination revealed a decreased sensation for touch, discrimination and vibration in all paresthetical regions and on the stem even up to dermatome C5. A mild elevation of the protein content, a mononuclear pleocytosis and oligoclonal bands were found in the cerebrospinal fluid. Magnetic resonance imaging of the cervical spinal cord showed a hyperintensive lesion in the region of the posterior tract at C6. With respect to these findings and after exclusion of other neurological affections, multiple sclerosis was diagnosed. The symptoms subsided spontaneously within five weeks, and the patient was discharged without any complaints. The diagnostic accuracy of the various findings is discussed.

Adult↗