Search PubMed⌕ Search

Biomedical subjects

B Chattopadhyay

Publications and source records attributed to B Chattopadhyay.

At least 19 recordsLinked to original sources
PubMed1992

Pseudobacteraemia with multiply-resistant Klebsiella pneumoniae resulting from contamination from the blood gas machine on a neonatal unit.

Klebsiella pneumoniae with an unusual antibiotic susceptibility pattern was isolated from blood cultures of seven unwell premature babies on the Special Care Baby Unit. Although the organism was sensitive to cefuroxime it was resistant to ceftazidime. It was also resistant to gentamicin, tobramycin, netilmicin, piperacillin and aztreonam but sensitive to ciprofloxacin, imipenem and amikacin. On extensive investigation to trace the source, a K. pneumoniae with the same susceptibility pattern as that obtained from blood cultures was isolated from the probe and probe cover on the blood gas machine but not from any other environmental samples or clinical specimens. Where clinically indicated, antibiotics were used to treat these babies, with success. The difficulty, however, of differentiating between true septicaemia and pseudobacteraemia could be enormous as withholding treatment will have disastrous consequences in genuine cases of bacteraemia.

Bacteremia↗
PubMed1991

Postoperative endophthalmitis.

Postoperative endophthalmitis is a rare complication of ophthalmic surgery. The use of prophylactic antibiotics and scrupulous surgical techniques will help to reduce its incidence, but sporadic cases may still occur. If postoperative endophthalmitis is a diagnostic possibility aggressive investigation and initial management improves the prognosis. More work needs to be done to evaluate the penetration of newer antibiotics into the eye and their therapeutic role. The use of corticosteroids also needs to be more carefully defined in the treatment of this potentially devastating disease.

Coagulase↗
PubMed1990

Disposition of nicotine and eight metabolites in smokers and nonsmokers: identification in smokers of two metabolites that are longer lived than cotinine.

The disposition of a single intravenous dose of 14C-nicotine was investigated in six cigarette smokers and six nonsmokers. Plasma and urinary elimination of both nicotine and cotinine was faster in smokers than in nonsmokers. In the urine of both smokers and nonsmokers, we identified nicotine and eight metabolites, including two new metabolites: metabolite A (3-hydroxycotinine glucuronide) and metabolite G (demethylcotinine delta 2',3'-enamine). Metabolites A and G were of particular interest because, in smokers, they both persisted longer than cotinine. This property renders them more sensitive than cotinine as potential indicators of passive exposure to cigarette smoke.

Adult↗
PubMed1990

Nerve growth factor-induced differentiation of human neuroblastoma and neuroepithelioma cell lines.

A series of neuroepithelioma and neuroblastoma cell lines were screened for nerve growth factor (NGF)-induced differentiation. All three neuroepithelioma cell lines and all nine neuroblastoma cell lines with amplified N-myc oncogene did not show any apparent NGF-induced differentiation. However, neurite extension was observed for three of six neuroblastoma cell lines with single-copy N-myc oncogene. The three responsive lines had a neuronal phenotype (short processes) which was enhanced by the addition of NGF. The three nonresponsive cell lines were flat without any processes. The addition of NGF to the responsive cell lines resulted in an up-regulation of neurofilament mRNA expression. Peripherin and synapsin, two markers of terminal neuronal differentiation, were not induced. There was little effect of NGF on the rate of cell growth or colony formation on soft agar. Binding of NGF to eight of the cell lines was analyzed by the method of Scatchard. Two responsive neuroblastoma cell lines and one nonresponsive neuroepithelioma cell line expressed both low- and high-affinity binding sites. Two nonresponsive neuroblastoma cell lines expressed only a small number of high-affinity binding sites, and two other nonresponsive neuroblastoma cell lines did not detectably bind NGF. Hence, NGF-induced differentiation is confined to a particular class of neural-related tumors, and, even for these cell lines, differentiation is incomplete.

Cell Differentiation↗
PubMed1989

Splenectomy, pneumococcal vaccination and antibiotic prophylaxis.

Fulminant sepsis following splenectomy remains a major problem. Even with the administration of pneumococcal vaccine and prophylactic antibiotics fatalities still occur. A better understanding of the complex immunological function of the spleen, its preservation as much as possible during surgery, potent vaccine and perhaps more effective antibiotics will, hopefully, help reduce mortality in some of these cases in future.

Anti-Bacterial Agents↗
PubMed1988

Prevention of congenital syphilis.

Syphilis, though rare, is a serious disease particularly in pregnancy, as undetected it will have severe adverse effects on the growing fetus. An alarming increase in the incidence of primary and secondary syphilis in some countries must prompt efforts to control congenital syphilis by screening and treatment of targeted high-risk groups of women.

Erythromycin↗
PubMed1986

The colonization of patients in an intensive treatment unit with gram-negative flora: the significance of the oral route.

An extensive survey of patients and the environment in a newly refurbished intensive care unit showed that the principle species on patients in sites other than the rectum were Pseudomonas aeruginosa, Klebsiella pneumoniae, Serratia marcescens, Acinetobacter anitratus and Enterobacter cloacae. Multiple episodes of cross-infection were occurring with 10 different strains of these organisms. Three oral solutions (mouthwashes, 'Clinifeeds' and residual water from nasogastric aspiration apparatus) were heavily contaminated with coliforms including some epidemic strains and this corresponded with the finding that colonization with the above species usually occurred first in the mouth or respiratory tract. Attempts to eliminate contamination of the solutions reduced colonization and cross-infection by over 50%, but did not eradicate it. Two sinks without heat-traps on the drains possibly provided a long term reservoir of epidemic strains.

Acinetobacter↗