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Biomedical subjects

G Biswas

Publications and source records attributed to G Biswas.

69 records · Page 4Linked to original sources
PubMed1978

Conjugative plasmids in Neisseria gonorrhoeae.

A conjugation system initially discovered in beta-lactamase-producing gonococci mobilized small non-selftransmissible R plasmids encoding beta-lactamase (penicillinase) production into other gonococci, Neisseria, and Escherichia coli. This conjugation system was mediated by a separate selftransmissible plasmid of 23.9 X 10(6) daltons, pFA2. Conjugative plasmids capable of mobilizing R plasmids were also found in nearly 8% of the non-penicillinase-producing gonococci. These were similar to pFA2 in size, buoyant density, and restriction endonuclease digest patterns but were less efficient than pFA2 in mobilization of the penicillinase plasmid pFA3. The presence of conjugative plasmids in gonococci isolated before the appearance of penicillinase-producing strains indicates that a conjugation system for plasmid transfer predated the appearance of R plasmids in gonococci.

Centrifugation, Density Gradient↗
PubMed1977

Conjugal transfer of the gonococcal penicillinase plasmid.

Certain gonococci, which heretofore have lacked a conjugal mating system, can sexually transfer a small plasmid (4.5 x 10)6) daltons) which carries the gene for beta-lactamase production. Frequencies of conjugal transfer were similar into diverse recipients (other gonococci, Neisseria flava, and Escherichia coli), which suggests that gonococci may transfer the plasmid promiscuously in nature.

Conjugation, Genetic↗
PubMedDate not supplied

Desmoplastic small round cell tumor: extra abdominal and abdominal presentations and the results of treatment.

BACKGROUND: Desmoplastic small round cell tumor (DSRCT) is a rare malignant neoplasm of adolescent males. Current multimodality treatment prolongs life and rarely achieves cure. AIM: To review the presenting features, histopathology and outcome of 18 patients with DSRCT treated at a single institution. SETTING AND DESIGN: This is a retrospective observational study of patients with DSRCT who presented at the Tata Memorial Hospital between January 1994 to January 2005. MATERIALS AND METHODS: Eighteen patients of DSRCT seen during this period were evaluated for their clinical presentation, response to chemotherapy and other multimodality treatment and overall survival. The cohort of 18 patients included 11 males (61%) and 7 females (39%) with a mean age of 16 years (Range 1(1/2)--30 years). Majority (83%) presented with abdomino-pelvic disease. The others, involving chest wall and extremities. There were 6 patients (33%) with metastatic disease at presentation. RESULTS: The treatment primarily included a multimodality approach using a combination of multiagent chemotherapy with adjuvant surgery and radiotherapy as applicable. A response rate of 39% (CR-1, PR-6), with chemotherapy was observed. The overall response rate after multimodality treatment was 39% (CR-5, PR-2). The overall survival was poor except in patients who had complete excision of the tumor. CONCLUSION: 0 Abdomino-pelvic site was the commonest presentation, the disease can occur at other non-serosal surfaces also. Despite aggressive treatment the outcome was poor. However, complete surgical excision seems to provide a better survival.

Abdominal Neoplasms↗
PubMedDate not supplied

Successful complete regression of isolated intramedullary spinal cord metastases from epithelial ovarian carcinoma with chemotherapy and radiotherapy.

Advances in the management of ovarian cancer by use of aggressive surgery and effective platinum-based chemotherapy have prolonged survival; this may have resulted in an alteration of the metastatic pattern of the disease and spread to unusual sites (e.g, CNS) has become more common. Also, with the availability of more sensitive imaging techniques, these tumors are being diagnosed with increasing frequency. Intramedullary spinal cord metastasis is rare. We report one such case treated successfully with chemotherapy and radiotherapy with long-term survival.

Administration, Oral↗
PubMedDate not supplied

Ewing's sarcoma with cutaneous metastasis--a rare entity: report of three cases.

Ewing's sarcoma (ES) is a small round cell tumor, usually arising from flat bones and diaphyseal region of long bones. It is commonly found in the first two decades of life. It is curable when diagnosed in the localized stage and requires multimodality treatment. ES is a chemosensitive tumor. It metastasizes commonly to lung, pleura and other bones. Less common sites of metastasis are lymph nodes, CNS and liver. Skin metastasis is extremely uncommon. It occurs in up to 9% of all patients with cancer. Growth pattern of cutaneous metastasis is unpredictable and may not reflect that of primary tumor. We hereby report three cases of Ewing's sarcoma that developed skin metastasis.

Adolescent↗
PubMedDate not supplied

Respiratory illness and tuberculin sensitivity among children below 15 years of age in a rural community.

The incidence of respiratory illness and tuberculin sensitivity of children below 15 years were studied among 245 families in village Chinimore and the observations were compared between two groups families keeping livestock and families non-keeping livestock. There were 135 (out of 446) children with respiratory illness with 30.2% incidence and 45 (out of 187 tuberculin tested) children were positive to Mantoux test. Families keeping livestock had statistically significantly more (P 25.18 of 0.1% level) tuberculin sensitive children.

Adolescent↗
PubMedDate not supplied

Retro-peritoneal plasmacytoma: a case report and review of literature.

Solitary Extramedullary Plasmacytoma (EMP) is an uncommon neoplasm. When diagnosed, head and neck region is its most likely location. Rarely, it may occur in the retro-peritoneum. We report a 44 year old man with solitary extramedullary plasmacytoma in the retro peritoneum (RPEMP). The patient did not show response to three cycles of VAD chemotherapy. Thereafter Surgical excision of the mass was performed successfully. This is probably the first case report from Indian subcontinent.

Adult↗
PubMedDate not supplied

Metachronous gastric diffuse large B-cell lymphoma and adenocarcinoma.

The development of gastric carcinoma in a patient with gastric lymphoma is rare. Helicobacter pylori is a common etiologic agent for both these conditions. We report a 38-year-old lady who was initially diagnosed to have gastric lymphoma and developed early gastric carcinoma on follow up. She was operated on for the carcinoma and is in complete remission since.

Adenocarcinoma↗