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Biomedical subjects

S Chadha

Publications and source records attributed to S Chadha.

At least 37 records · Page 2Linked to original sources
PubMed1993

An immunohistochemical evaluation of androgen and progesterone receptors in ovarian tumors.

To visualize the heterogeneity of androgen receptor (AR) and progesterone receptor (PR) expression in ovarian tumors, 61 specimens were studied immunohistochemically using specific mouse monoclonal antibodies. The tested ovarian tumors included ovarian carcinomas of serous, mucinous, endometrioid, undifferentiated, and clear cell types as well as borderline epithelial tumors, mucinous cystadenomas, granulosa cell tumors, metastatic ovarian tumors, and one case of immature teratoma. Sixty-seven percent of ovarian carcinomas expressed AR, while 46% of the ovarian carcinomas expressed PR. In addition, the three tested borderline epithelial tumors were AR positive. Androgen receptor and PR were primarily localized in the nuclei of ovarian tumor cells. In three tumors focal staining of intervening stroma cells was observed. Interestingly, 35 of the granulosa cell tumors expressed PR as well as AR. All tumor types displayed a wide range in their proportions of AR- and PR-positive tumor cells. A poor correlation, however, was observed when semiquantitative immunohistochemical AR staining results on 17 ovarian carcinomas were compared with biochemical cytosol AR estimations using the dextran-coated charcoal method. Our study indicates that AR as well as PR is expressed by a substantial proportion of ovarian borderline and malignant tumors and that there is a strong heterogeneity in expression of AR and PR. It is possible to evaluate the prognostic significance of these receptors in ovarian cancers on fresh-frozen tumor specimens using a simple immunohistochemical technique.

Carcinoma↗
PubMed1993

The Houston Academy of Medicine--Texas Medical Center Library management information system.

A management information system (MIS) provides a means for collecting, reporting, and analyzing data from all segments of an organization. Such systems are common in business but rare in libraries. The Houston Academy of Medicine-Texas Medical Center Library developed an MIS that operates on a system of networked IBM PCs and Paradox, a commercial database software package. The data collected in the system include monthly reports, client profile information, and data collected at the time of service requests. The MIS assists with enforcement of library policies, ensures that correct information is recorded, and provides reports for library managers. It also can be used to help answer a variety of ad hoc questions. Future plans call for the development of an MIS that could be adapted to other libraries' needs, and a decision-support interface that would facilitate access to the data contained in the MIS databases.

Academic Medical Centers↗
PubMed1992

Occurrence of epidermal growth factor receptors in benign and malignant ovarian tumors and normal ovarian tissues: an immunohistochemical study.

Epidermal growth factor receptor (EGF-R) was studied with monoclonal antibody 2E9 on 50 ovarian tumors of various histological types and 10 non-tumorous ovarian tissues by immunohistochemistry. Enhanced expression was observed in 26/50 (52%) of the tumors. Only 25 out of 46 epithelial tumors (54%) showed positivity in epithelial tumor cells. Staining was cytoplasmic in all cases. No correlation was established between EGF-R expression and the histological type of the epithelial tumor. Apart from EGF-R expression in tumor cells, low immunoreactivity was also observed in stromal and endothelial cells in both normal and tumorous ovarian tissues. Furthermore in 8/9 specimens containing necrotic areas, EGF-R was noticed in these areas as well. Both of the latter observations may have impact on the evaluation of the prognostic value of EGF-R activity in tumors, when based on EGF-R measurements using biochemical binding studies. We therefore recommend that EGF-R is measured with both methods in studies regarding its clinical value.

Adenocarcinoma↗
PubMed1992

Effect of sulfasalazine on adaptive and functional changes in intestine of normal and protein-calorie-malnourished rats.

The effects of sulfasalazine (500 mg/kg body weight daily for 35 days) and its subsequent recovery for another 35 and 65 days have been investigated on the intestinal uptake of certain end-product nutrients, viz. glucose, leucine, alanine, and calcium, in normal and protein-calorie malnourished (PCM) male albino rats. Sulfasalazine administration caused a reduction in body weight in PCM animals, while intestinal weight and length as well as protein and nucleic-acid contents were reduced in both normal and PCM animals. Serum proteins also showed a decrease in PCM rats. PCM rats showed elevated levels of glucose, amino acids, and calcium uptake by the intestinal segments, but sulfasalazine feeding inhibited the uptake of nutrients both in normal-fed and malnourished animals. All these changes were found to be reversible after the withdrawal of drug treatment. Sulfasalazine caused a decrease in the Na(+)-dependent (active) glucose uptake as well as the Na(+)-independent (passive) process. The kinetic parameters of glucose uptake indicate that the drug might interfere with the transport/carrier protein of these nutrients, because reduction was observed in maximum uptake velocity (Jmax) of these systems without any change in the affinity constant (Kt).

Adaptation, Physiological↗
PubMed1991

Low-grade immature teratomas with peritoneal gliomatosis; a case report.

Immature teratomas with peritoneal gliomatosis are rare. Eight cases have been registered by the Dutch Ovarian Tumor Committee and one patient, presented in this paper, was treated recently. The follow-up in these cases indicates a good prognosis, even in grade 2 teratomas. Peritoneal implants do not influence adversely the prognosis when they are composed of mature glial tissue. A conservative approach seems to be justified.

Adult↗
PubMed1991

Ovarian morphology in long-term androgen-treated female to male transsexuals. A human model for the study of polycystic ovarian syndrome?

Descriptions of the effect of androgens on ovarian human tissues are exceptional. This opportunity was provided for us by 17 women with transsexualism--female to male transsexuals (TSX)--who had been given androgens for a mean period of 21 months before hystero-salpingo-oophorectomy took place. Twenty-nine ovaries from TSX and 14 control ovaries from 13 regularly cycling women were examined. As compared with controls, TSX ovaries were enlarged and displayed a two-fold increase in cystic follicles and a 3.5-fold increase in atretic follicles; the ovarian cortex was collagenized and three-times thicker. Theca interna hyperplasia and luteinization were uniformly observed in TSX cystic follicles. Stromal hyperplasia was a constant finding in TSX ovaries, accompanied by clusters of luteinized stromal cells in 12 cases. Eventually, these findings met the histological criteria for the diagnosis of polycystic ovaries. These observations demonstrate that androgens alone may induce polycystic changes. The assumption that the role of androgens is pivotal at the follicular level--inducing follicle growth arrest and accelerating cystic changes--in the genesis of polycystic ovaries is reinforced.

Adolescent↗
PubMed1991

Alterations and reversibility of the effects of gossypol acetic acid on the intestinal uptake of end product nutrients in normal and protein calorie-malnourished male rats.

The effects of gossypol acetic acid, an experimental male antifertility agent, 20 mg/kg body weight daily for 15 days and its subsequent withdrawal have been investigated on the intestinal uptake of certain end product nutrients, namely glucose, leucine, alanine and calcium, in normal and protein-calorie-malnourished (PCM) male albino rats. Gossypol feeding caused a reduction in body weight, intestinal weight and length, protein and nucleic acid contents in both normal and PCM animals. Serum parameters, e.g. total protein, albumin and globulin, also showed a decrease in PCM rats. PCM per se considerably elevated the uptake of nutrients but gossypol feeding inhibited the uptake of nutrients both in normal-fed and malnourished animals. Gossypol caused a decrease in the Na(+)-dependent (active) glucose uptake while the Na(+)-independent (passive) process was not altered. The kinetic parameters of glucose uptake indicate that gossypol might be interfering with the transport/carrier protein of these nutrients as reduction in maximum uptake velocity (Jmax) of these systems was observed without, however, any change in the affinity constant (Kt).

Amino Acids↗
PubMed1990

Feasibility of the immunohistochemical detection of endogenous steroids in paraffin-embedded ovarian tumours.

Formalin-fixed, paraffin-embedded samples from 25 ovarian granulosa cell tumours and six poorly differentiated ovarian carcinomas were examined immunohistochemically for the presence of estradiol, testosterone and progesterone. Twenty-four of the 25 granulosa cell tumours stained for estradiol predominantly in granulosa cells and also in the theca cells, but none of the carcinomas were positive. All the granulosa cell tumours and five out of six carcinomas were positive for progesterone, while 13 granulosa cell tumours and three carcinomas stained moderately positive for testosterone. No clear-cut relationship was observed between positivity for estradiol in granulosa cell tumours and occurrence of endometrial hyperplasia. In two cases of granulosa cell tumours, 1-15% cells showed ultrastructural features of steroid synthesis: i.e. moderate to abundant smooth endoplasmic reticulum and mitochondria with tubular cristae. This is in contrast with the diffuse immunohistochemical staining reaction of granulosa cell tumours with antisteroid antibodies. To evaluate the significance of immunohistochemical reactions for estradiol, four estradiol-containing tumours were tested by radioimmunoassay for the presence of estradiol before and after dehydration. As expected, treatment with organic solvents leads to a drastic reduction in estradiol content below the detection level of the assay. The results indicate that immunohistochemical staining for steroids of paraffin-embedded granulosa cell tumours is of limited value.

Adult↗
PubMed1990

Gossypol-induced inhibition of glucose uptake in human ejaculated spermatozoa may be mediated by lipid peroxidation.

Gossypol, a plant-derived polyphenolic compound known to exert contraceptive actions in men, inhibits 14C-glucose uptake in vitro in human ejaculated spermatozoa. Spermatozoal glucose uptake was found to increase monotonically up to 40 min, and then decreased by 60 min, possibly because of the saturation of the transport loci in the membrane. Gossypol at the concentrations of 5 and 10 microns caused a reduction of both the linear portion of the uptake and the fall afterwards. Gossypol similarly affects both the Na-dependent and -independent glucose uptake. The kinetic parameters of glucose uptake indicate that gossypol might be interfering with the transport/carrier protein as reduction in maximum uptake velocity (Vmax) was observed without any change in the affinity constant (Km). Similarly, gossypol also produced an increase in spermatozoal lipid peroxidation as evidenced by a steep rise in thiobarbituric acid reaction products in the human sperm cells. A significant decrease in total phospholipid level and the individual classes was noted after gossypol addition. Gossypol-induced inhibition of glucose uptake may be related to the generation of lipid peroxides and consequent membrane damage.

Glucose↗
PubMed1990

Flow cytometric DNA ploidy analysis of ovarian granulosa cell tumors.

The nuclear DNA content of 50 ovarian tumors initially diagnosed as granulosa cell tumors was measured by flow cytometry using paraffin-embedded archival material. The follow-up period of the patients ranged from 4 months to 19 years. Thirty-eight tumors were diploid or near-diploid, while 5 were aneuploid. DNA profiles of 7 tumors could not be evaluated. All 50 tumors were immunohistochemically tested for expression of intermediate filament proteins vimentin and cytokeratin and epithelial membrane antigen. The cells of all but 3 tumors expressed vimentin. These 3 vimentin-negative tumors were positive for cytokeratin and epithelial membrane antigen. They were highly aneuploid and though originally diagnosed as granulosa cell tumors, most likely represent undifferentiated carcinomas. Hence, only 2 typical granulosa cell tumors were aneuploid. In addition, frozen tissue samples from 9 of 10 granulosa cell tumors showed a DNA diploid content. Our results indicate that granulosa cell tumors tend to be diploid or have only minor ploidy abnormalities which is in line with their relatively benign character. An undifferentiated carcinoma should be considered in the differential diagnosis of tumors with a high DNA index.

DNA↗
PubMed1989

Immunohistochemistry of ovarian granulosa cell tumours. The value of tissue specific proteins and tumour markers.

Paraffin-embedded material of 47 ovarian tumours primarily diagnosed as granulosa cell tumours, including 2 cases of juvenile granulosa cell tumour, were studied immunohistochemically for the presence of intermediate filament proteins, epithelial membrane antigen and tumour markers. Forty-one lesions, including the 2 juvenile granulosa cell tumours, were vimentin positive, while keratin and epithelial membrane antigen expression could not be detected. Six tumours primarily diagnosed as poorly differentiated malignant granulosa cell tumours were vimentin negative, showed a mild to moderate positivity for keratin and intense positivity with the anti-epithelial membrane antigen antibody. These latter tumours were therefore classified as undifferentiated ovarian carcinomas, corresponding to their significantly poorer prognosis and shorter survival when compared with the granulosa cell tumours. Two of these six tumours were positive for carcino-embryonic antigen. Two small cell carcinomas of the ovary studied in addition expressed keratin in a proportion of tumour cells while no epithelial membrane antigen or vimentin was detectable. None of the tumours tested for alpha-fetoprotein, human chorionic gonadotrophin, human placental alkaline phosphatase and human placental lactogen, were positive. The data indicate the value of antibodies directed against intermediate filament proteins and epithelial membrane antigen to distinguish granulosa cell tumours from poorly differentiated carcinomas, a worthwhile distinction considering the much better prognosis of granulosa cell tumours.

Biomarkers, Tumor↗
PubMed1989

Reversibility of the effects of gossypol acetic acid, an antispermatogenic/antifertility agent on the intestinal structure and functions of male albino rats.

The effects of Gossypol acetic acid (10 mg/kg b. wt. daily for 15 days), an experimental male antifertility agent and its subsequent withdrawal for another 15 days, on the structure and functions of the rat small intestinal tract have been investigated. Gossypol feeding causes a reduction in body weight and intestinal weight, length, protein, and nucleic acid contents. A 27%-50% reduction in the uptake of glucose, alanine, leucine, and calcium is observed after Gossypol feeding which is found to be reversible after 15 days of withdrawal of the drug. Gossypol also causes a significant reduction in the activities of sucrase, lactase, maltase and alkaline phosphatase in the intestinal homogenates as well as in the purified brush border membrane of the microvillus. A decrease in the maximum of apparent enzyme velocity and no change in the substrate affinity constant in these digestive hydrolases are observed on Gossypol treatment. It also causes a shift in the transition temperature in these enzymes and predictably changes the energy of activation both below and above the temperature of transition, although the Arrhenius expression of the temperature dependence still shows proximity, non-linearity, and is parallel to the control group. These changes are reversed on withdrawal of the drug and during the subsequent recovery period. Recovery experiments also show near identical values in kinetic parameters (Kt and Jmax) of 14C-glucose uptake in jejunal segments both in the presence and absence of Na+ ions. Also, no difference is observed between the control and recovery groups with respect to body and intestinal weight, intestinal length, and DNA, RNA, protein, lactate dehydrogenase and glucose-6-phosphate phosphohydrolase values in the intestinal homogenates. Phospholipid, cholesterol and sialic acid levels in both the groups also show nearly identical values. Molecular mechanism of the effects of Gossypol on brush border membrane-bound enzyme/carrier molecules operation is discussed in view of the kinetic and thermodynamic data obtained.

Amino Acids↗
PubMed1988

Malignant transformation in benign cystic teratomas: dermoids of the ovary.

Twenty-four cases with a malignant change involving one of the elements of a benign ovarian dermoid cyst are reported. Squamous cell carcinoma was most frequent. Eighteen patients (75%) were over 50 years of age. The prognosis is rather good if the tumor has not extended beyond the capsule, 85% surviving without detectable disease after 4 months to 9 years. The prognosis is very poor if the tumor has extended beyond the capsule, over 80% dying within 2 years. Hysterectomy with bilateral salpingo-oophorectomy is the treatment of choice, certainly in older patients. Additional treatment with cytostatics or radiation seems to have little influence on the prognosis.

Adult↗
PubMed1988

Effects of gossypol acetic acid on the absorptive and digestive functions of rat intestine.

Oral administration of Gossypol acetic acid (10 mg/kg body wt./day, daily for 15 days), an experimental antifertility agent to male rats, caused significant reduction in the uptake of glucose, alanine, leucine and calcium in the small intestinal segments. Gossypol also caused significant decrease in the intestinal brush border membrane--associated enzymes, sucrase, lactase, maltase and alkaline phosphatase. Kinetic analysis indicated that Gossypol decreased the apparent velocity of the disaccharidases while the Km was not altered. It also caused a shift in the transition temperature in these enzymes and predictably changed the energy of activation both below and above the transition temperature, although the Arrhenius expressions of the temperature dependence still showed proximity and were parallel to the control group.

Administration, Oral↗
PubMed1987

Raised serum alpha-fetoprotein in Sertoli-Leydig cell tumor (androblastoma) of ovary: report of two cases.

Two cases of Sertoli-Leydig cell tumor (SLCT) of the ovary associated with elevated serum alpha-fetoprotein (AFP) levels are described. A 16-year-old girl (case 1) had a Sertoli-Leydig cell tumor containing heterologous elements in the form of mucinous epithelium; AFP was demonstrated within the Sertoli cells by immunohistochemical techniques. An 11-month-old girl (case 2) had a SLCT with a retiform pattern and heterologous elements in the form of cells resembling hepatocytes; AFP was localized in the hepatocytes by immunohistochemical techniques.

Adolescent↗