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S N Ghosh

Publications and source records attributed to S N Ghosh.

104 records · Page 6Linked to original sources
PubMedDate not supplied

Recognition of helper T cell epitopes in envelope (E) glycoprotein of Japanese encephalitis, west Nile and Dengue viruses.

Helper T (Th) cell antigenic sites were predicted from the primary amino acid sequence (approximately 500 in length) of the envelope (E) glycoprotein (gp) of Japanese encephalitis (JE), West Nile (WN) and Dengue (DEN) I-IV flaviviruses. Prediction of Th epitopes was done by analyzing the occurrence of amphipathic segments, Rothbard-Taylor tetra/pentamer motifs and presence of alpha helix-preferring amino acids. The simultaneous occurrence of all these parameters in segments of E gp were used as criteria for prediction as Th epitopes. Only one cross reactive epitope was predicted in the C-terminal region of the E gp predicted segments of all flaviviruses analyzed. This region is one of the longest amphipathic stretch (approximately from 420 to 455) and also has a fairly large amphipathic score. Based on the predicted findings three selected peptides were synthesized and analyzed for their ability to induce in vitro T cell proliferative response in different inbred strains of mice (Balb/c, C57BL6, C3H/HeJ). Synthetic peptide I and II prepared from C-terminal region gave a cross reactive response to JE, WN and Den-II in Balb/c and C3H/HeJ mice. Synthetic peptide III prepared from N-terminal region gave a proliferative response to DEN-II in Balb/c strain only, indicating differential antigen presentation.

Algorithms↗
PubMedDate not supplied

Prognosis and incidence of sex chromatin in breast cancer. A preliminary report.

Results of two studies, based on a total of 126 patients (prospective--76 cases and retrospective--50 cases), on the incidence of the sex chromatin in the cancerous tissue are presented. For evaluation of prognosis in the retrospective study with a five year follow up, sex chromatin incidence was correlated with other prognositc factors such as lymph node metastasis, the disease free interval of distant metastasis and the size of the tumor. Whereas positive significant correlation between sex chromatin incidence and a five year survival time or disease free interval of distant metastasis was observed, no correlation was seen between sex chromatin counts and lymph node metastasis or the size of the tumor.

Breast Neoplasms↗
PubMedDate not supplied

Loss of X-chromatin and X-chromosome activation in HeLa cells.

Activation of second X-chromosome by the action of estradiol-17 beta was studied with HeLa cells. The incidence of X-chromatin in estrogen-treated cells decreased remarkably from 55% to 6%. Further, heavy incorporation of 3H-uridine occurred in the X-chromatin bodies of the treated cells while no such labelling was observed in controls. There was also a manifold increase in the activity of the enzyme G-6-PD in steroid-treated cells, and this increase in enzyme activity could be inhibited by addition of actinomycin D. A nonestrogenic steroid such as testosterone had no effect on these parameters. These observations do indicate activation of second X-chromosome of HeLa cells by estradiol-17 beta.

Enzyme Activation↗
PubMedDate not supplied

Prediction of biological behaviour of human breast cancer using multiple parameters. A preliminary study.

Prediction of early metastases in individual patients has been attempted by combined evaluation of a battery of recognised parameters such as blood vessel invasion (BVI) of tumor cells, Barr body frequency (BBF), plasminogen activator (PA), collagenase, estradiol receptors (ER), progesterone receptors (PgR), and peroxidase activity (PRA) in 18 malignant and 3 benign (control) breast tumors. Since breast tumor cells spread through the blood vessels, the cases were divided into BVI (+) and BVI (-) groups. Results show that in the former group, all the cases had poor prognosis and two even had distant metastases within one year. In BVI (-) group, 9 out of 12 appeared to have good prognosis.

Blood Vessels↗
PubMedDate not supplied

Expression of tumor cell properties in synovial cells in culture.

The tumorigenic properties of human rheumatoid arthritis synovial cells in culture were investigated. The synovial cells developed good colonies and secreted plasminogen activator (PA) and collagenase in the cell cultures, as do Hela cells. Since PA and progesterone receptor (PgR) are considered to be end products of estradiol action in breast cancer cells, the estrogen receptor (ER) and PgR content in these cells was also assayed. Large amounts of ER and PgR were detected in the synovial cells in culture, even though these cells are not targets for sex steroids. Study of the cytomorphologic changes in the synovial cells in culture revealed many characteristics generally observed in neoplastic cells. Whether any or all of these observations have any implication in prognosis or therapy in this disease remains to be studied.

Cell Division↗
PubMedDate not supplied

Barr body frequency in esophageal cancer in Indian women.

In a retrospective study, Barr body frequency was analyzed in 50 consecutive cases of esophageal cancer in females. The majority (95%) of the tumors had less than 20% Barr body frequency (of which 80% showed less than 10%), while normal controls showed 30% to 45% Barr body frequency. The mechanism(s) involved in lowering the frequency is not known at present.

Esophageal Neoplasms↗