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Biomedical subjects

R K Gupta

Publications and source records attributed to R K Gupta.

At least 415 records · Page 23Linked to original sources
PubMed1992

Presence of Epstein-Barr virus in Hodgkin's disease is not exclusive to Reed-Sternberg cells.

Thirty-three cases of Hodgkin's disease (HD) have been studied for the presence of Epstein-Barr virus (EBV) using a novel nonisotopic in situ hybridization procedure, based on the detection of Epstein-Barr encoded RNAs with oligonucleotide probes. An intense and morphologically distinct nuclear staining, sparing the nucleolus was seen in a total of 12 cases (36%). In six of these cases, the signal was located to the Hodgkin and Reed-Sternberg cells (HR-S); in the other six positive cases, the signal was observed only in the non-neoplastic small lymphocytes. These lymphocytes were few in number and immunocytochemistry results were consistent with a B-cell phenotype. The presence of EBV in those cases characterized by nuclear staining of small lymphocytes was confirmed by the polymerase chain reaction (PCR) analysis. The authors report the detection of EBV in small lymphocytes in HD by in situ hybridization and discuss the implications of these findings in relation to the proposed etiologic association between EBV and HD.

Adolescent↗
PubMed1992

Magnetic resonance imaging in pancreatic diseases: comparison with other imaging techniques.

Magnetic resonance imaging (MR) was performed in 14 healthy subjects and 16 patients with pancreatic disease. All the 16 patients were subjected to ultrasonography (USG), computed tomography (CT) and MR while endoscopic retrograde cholangiopancreatography (ERCP) was performed in 10 cases. In one patients with adenocarcinoma and two with gastrinoma, MR demonstrated abnormalities while USG and CT were normal. MR was, however, inferior to ERCP in demonstrating ductal abnormalities in chronic pancreatitis. Our initial experience suggests that MR is superior to other imaging modalities in the diagnosis and staging of pancreatic tumors; however, it is inferior to ERCP in the diagnosis of pancreatitis.

Adenocarcinoma↗
PubMed1992

Metastasising congenital subcutaneous sacrococcygeal ependymoma.

A case of myxopapillary ependymoma located subcutaneously in sacrococcygeal area of a 18 months male child with metastasis to right inguinal lymph nodes is described; the tumour was present since birth. Histological examination of the tumour besides myxopapillary structures, also revealed an ependyma lined cystic space, resembling ventricular cavity. So far only two cases of congenital metastasising subcutaneous sacrococcygeal ependymoma have been described. However, the present case had a very aggressive post-operative biological behaviour.

Ependymoma↗
PubMed1992

A correlative study of serum zinc and in vivo cell mediated immune status in rheumatic heart disease.

This study was conducted to determine the zinc status and assess relationship between serum zinc and in vivo cell mediated immunity (CMI) in patients with rheumatic heart disease (RHD). The study comprised 22 patients with active rheumatic heart disease (ARHD), 15 patients with chronic rheumatic heart disease without activity (CRHD) (selection based on Jone's Criteria--Revised), and 15 age and sex matched healthy control. Zinc estimation was done by atomic absorption spectrophotometer. To assess CMI in vivo, phytohaemagglutinin skin test and skin window test were done. Serum zinc and in vivo CMI in patients with ARHD and CRHD compared with controls. Mean serum zinc was significantly decreased in patients with ARHD and CRHD, more pronounced in the former (P less than 0.001); and mean 24 h urinary zinc was significantly increased in patients with ARHD (P less than 0.001) as compared to controls. A significant depression in CMI in vivo was observed in patients with ARHD and CRHD (P less than 0.001). A significant positive correlation was seen among serum zinc and markers of in vivo CMI (P less than 0.001). In conclusion, depletion of zinc, observed in RHD, probably causes immune alterations and suggest role of zinc in immunopathogenesis of RHD. Zinc supplementation may alter the course of rheumatic fever and RHD.

Adolescent↗
PubMed1992

Comparative stabilities of glutaraldehyde & heat inactivated pertussis vaccine components of adsorbed DPT vaccine with different preservatives.

The stability of pertussis component (glutaraldehyde or heat inactivated pertussis vaccine) of the adsorbed diphtheria-pertussis-tetanus (DPT) vaccine preserved in thiomersal or benzethonium chloride was studied at 4-8 degrees C and 35 degrees C for 30 days. The potency of pertussis component of adsorbed DPT vaccine preserved with benzethonium chloride was lower than that preserved with thiomersal. After the initial loss of potency of pertussis component in the benzethonium chloride during blending, the stability of potency of pertussis component at 4-8 degrees C and 35 degrees C for 30 days was similar for vaccines preserved with either benzethonium chloride or thiomersal. The stability of both types of pertussis components inactivated with glutaraldehyde or heat was also similar at both the temperatures for 30 days.

Diphtheria-Tetanus-Pertussis Vaccine↗
PubMed1992

Protein A potentiates lymphokine-activated killer cell induction in normal and melanoma patient lymphocytes.

The effects of purified protein A from Staphylococcus aureus Cowan I stain on induction of lymphokine (IL-2) activated killer (LAK) activity were studied in normal as well as melanoma patient's lymphocyte. The coculture of peripheral blood mononuclear cells (PBMC) with various doses of protein A (0.001, 0.01 and 0.1 microgram/ml) and IL-2 (100 U/ml) for 4 days produced synergistic effect on the LAK cells mediated cytotoxicity. The potentiation of cytotoxicity and lytic ability of LAK cells against NK sensitive (K-562) and NK-resistant (M14) tumor cells were observed. Further there was potentiation of DNA synthesis in PBMC after 4 days culture. Similar results were found when PBMC from melanoma patients were cultured with PA and IL-2. The potentiation of LAK cell induction associated with its cytotoxic and lytic potential by low doses of IL-2/PA regiment may be helpful in the development of LAK immunotherapy of the cancer patients.

Drug Synergism↗
PubMed1992

Effect of clinicobiochemical bias on the sensitivity of nuclear imaging in detecting hepatic malignancies.

A retrospective analysis of the sensitivity of nuclear imaging in detecting hepatic malignancies has been done. Effects of clinical and liver function test bias have been studied on the ascribed sensitivity. The clinicobiochemical bias raises the detection sensitivity from 66.7% to 90.7% (p less than 0.001) but decreases the specificity of nuclear imaging significantly (p less than 0.05).

Bias↗
PubMed1991

19F-NMR study of the effect of lead on intracellular free calcium in human platelets.

Lead has been shown to affect calcium homeostasis. However, there is no prior evidence to indicate an effect of low concentrations of lead in the environment (approximately 1 microM) on the intracellular free Ca2+ concentration in any human tissue. We have investigated the effect of lead on the intracellular free Ca2+ concentration of human blood platelets using 19F-NMR and a fluorinated intracellular Ca2+ indicator. We report a basal intracellular free Ca2+ value of 172 +/- 8 nM. Treatment with 1, 5, 10 and 25 microM Pb2+ resulted in average increases in intracellular free Ca2+ of 39%, 91%, 135% and 172%, respectively. The percent increase in intracellular free Ca2+ was linearly and positively correlated with the log of Pb2+ concentration. Using atomic absorption spectroscopy, a significant increase in total calcium of approx. 10 nmol/mg protein was found in 25 microM Pb2+ treated platelets. This indicates that influx of external Ca2+ contributes to the observed increase in free Ca2+. The results provide an explanation for the previously reported effects of lead on platelet function, and suggest a mechanism for low level lead-induced hypertension.

Adenosine Triphosphate↗
PubMed1991

Fine-needle aspiration cytology of tubular carcinoma of the breast in a young woman.

The fine-needle aspiration cytology (FNAC) findings in a case of rare tubular carcinoma of the breast in a young woman are presented. The rarity of occurrence of tubular carcinoma in the breast and the bland and mostly orderly appearance of cells in the FNAC sample, as in tissue, were considered to cause the difficulty in the diagnosis of this tumor; also, these were features also found in other conditions of the breast. Furthermore, cytologists have limited experience with the diagnosis of this neoplasm from FNAC samples. It is therefore felt that (1) a cautious attitude is necessary when commenting on FNAC samples until more specific criteria are forthcoming for the diagnosis of this neoplasm; and (2) if cellular atypias are seen in FNAC samples, these should be reported with a recommendation for removal of the breast lump and a detailed tissue examination.

Adenocarcinoma↗
PubMed1991

Needle aspiration cytology and immunocytochemical study in a case of angiosarcoma of the breast.

A case of angiosarcoma of breast diagnosed by needle aspiration cytology (NAC) is documented. The significant features which enabled the NAC diagnosis included presence of spindly to polygonal malignant endothelial lining cells appearing as papillary tufts merging with solid areas, branching effects, and presence of microacinar structures lined with abnormal spindly to polygonal cells indicative of vasoformative structures. Immunostaining for factor VIII and vimentin was strongly positive in the malignant spindly polygonal endothelial cells and further supported the NAC diagnosis. Similar findings were also seen in sections of cell blocks from aspirate and excised biopsy tissue from the breast tumor in hematoxylin-eosin stained sections and on immunostaining. Despite the rarity of occurrence of angiosarcoma in the breast it was felt that its cytologic diagnosis is possible especially in cases in which the lesion is extensive because of a good chance of getting a cellular sample on aspiration. This can be of considerable value for deciding an appropriate management and as a possible guide to prognosis.

Biomarkers↗
PubMed1991

A case of neurilemoma (schwannoma) that mimicked a pleomorphic adenoma (an example of potential pitfall in aspiration cytodiagnosis).

Needle-aspiration cytology of a case of benign neurilemoma (Schwannoma) from the neck is presented. It was clinically diagnosed as an enlarged lymph node, while on aspiration cytology, it was diagnosed as a pleomorphic adenoma. An excision biopsy, however, was diagnostic of neurilemoma. A review of cytologic material was undertaken, and it was felt that the cytologic features in Papanicolaou stained preparations in the aspirate were present that initially should have enabled the correct cytodiagnosis and distinction from a pleomorphic adenoma. The findings presented in this study were considered to be an example of a potential pitfall in the aspiration cytodiagnosis of a neurilemoma.

Biopsy, Needle↗
PubMed1991

The diagnostic impact of needle aspiration cytology of the breast on clinical decision making with an emphasis on the aspiration cytodiagnosis of male breast masses.

Our experience with a total of 7,231 needle aspirates of the breast was reviewed. Ninety-nine cases from the total of 7,231 aspirates studied were from male patients. While an aspiration cytodiagnosis of gynecomastia was made in most of these cases, carcinoma was diagnosed in four cases. Although a clinical distinction between male breast cancer and gynecomastia is often difficult, we found needle aspiration cytology a very useful initial investigation for making this distinction.

Adolescent↗
PubMed1991

A study of malignant lymphomas in Iran, based on the updated Kiel classification.

One hundred and sixty-two consecutive cases of malignant lymphomas were collected from two diagnostic centres in north and south Iran. Tissue samples were examined by immunohistological methods, and the non-Hodgkin's lymphomas were classified according to the updated Kiel classification. The distribution of the different types of malignant lymphoma in this study is compared with the situation in Western countries.

Adolescent↗
PubMed1991

The effects of staphylococcal protein A on human lymphokine-activated killer cell induction.

Staphylococcal protein A (Cowan strain; SpA), a biologically active molecule capable of inducing augmented natural killer (NK) cell cytotoxicity, was studied in regard to its effects on lymphokine-activated killer (LAK) cell development. SpA, when co-cultured with interleukin-2 (IL-2) for 4 days, significantly augmented both LAK activity against NK-resistant M14 (melanoma) target cells and DNA synthesis of peripheral blood mononuclear cells (PBMC). This enhancement occurred with SpA concentrations of 1-100 micrograms/ml in a dose-dependent fashion; concentrations above 100 micrograms/ml were no more effective. When SpA (10 micrograms/ml) was added to PBMC cultures with various IL-2 concentrations, cytotoxicity was increased over controls with IL-2 alone. The peak cytotoxic effect reached a plateau at 80 U/ml IL-2. SpA alone induced early (day 1) cytotoxicity, which rapidly declined. SpA alone did not induce PBMC proliferation but it did increase expression of CD25 (Tac), IL-2 receptor alpha chain, on CD56(Leu19)-positive and -negative cells. The potentiating effect of SpA was significantly enhanced in serum-free medium. If either human AB serum or human IgG was added to cultures SpA-enhanced LAK cytotoxicity was diminished. The addition of anti-interferon gamma (anti-IFN gamma) antibody, but not anti-IFN alpha, inhibited (SpA+IL-2)-induced cytotoxicity, indicating that IFN gamma is partially responsible for the additive cytotoxic effect.

Antigens, Differentiation, T-Lymphocyte↗