Biomedical subjects

S Daya

Publications and source records attributed to S Daya.

132 records · Page 8Linked to original sources

PubMed1985

Ethnic differences in human lymphocytic cyclic AMP production after isoprenaline stimulation and propranolol blockade.

The stimulatory effects of isoprenaline on human lymphocytic cyclic AMP (cAMP) and blockade by propranolol were studied in vitro in healthy Black and White volunteers. Basal levels of lymphocytic cAMP were significantly higher in Blacks than in Whites. Stimulation with isoprenaline caused a dose-related increase in cAMP, which was in concentrations of 10(-9) to 10(-5)M significantly greater in Blacks than in Whites. Blockade by 10(-4)M propranolol did not affect basal cAMP levels significantly, but increases in cAMP levels were significantly smaller in both groups after 10(-9) to 10(-2)M isoprenaline, while differences between cAMP levels in Blacks and Whites were still significant at concentrations 10(-9) to 10(-3)M. The increased cAMP concentration in lymphocytes of Blacks probably reflects a higher degree of beta 2-adrenoceptor activity which could be due to either a greater number and/or greater sensitivity of lymphocytic beta 2-adrenoceptors in Blacks than in Whites.

Black People↗

PubMed1984

The effect of multiparity on intrasellar prolactinomas.

A complete reassessment of ovulation, pituitary reserve and function, and sella turcica anatomy was carried out in nine multiparous patients with intrasellar prolactinomas to determine whether long-term bromocriptine therapy was required and to document the natural history of the disease after two or more pregnancies. After the last pregnancy, bromocriptine was discontinued and pituitary function and anatomy and prolactinoma activity were reassessed with documentation of ovulation (basal body temperature graphs and menstrual history), search for fat droplet-positive galactorrhea, pituitary fossa tomography, computerized tomographic scan, triple-bolus testing, and visual fields. These data were compared with a similar workup carried out prior to the first pregnancy. Three groups of eventual outcomes were identified radiologically. Anterior pituitary gland function and reserve remained normal in all, and no neurological sequelae were noted. Four patients did not require long-term treatment. A hypothesis of autoinfarction of the adenoma is raised, since three patients were shown to have empty sellae.

Adult↗

PubMedDate not supplied

Transvaginal ultrasound scanning in early pregnancy and correlation with human chorionic gonadotropin levels.

Pregnancy can be detected early using transvaginal ultrasonography and human chorionic gonadotropin (hCG) measurements. The purpose of this study was to correlate serum hCG levels with transvaginal gestational sac measurements. The mean sac diameter (MSD) and gestational sac diameter (GSD) were calculated as the mean and cube root of the product, respectively, of three sac dimensions taken at right angles. A nonlinear relationship between hCG (natural logarithm) and MSD and GSD was observed. The data were best fitted by a second order polynomial regression model (r2 = 0.98), thereby establishing normal hCG levels for various gestational sac dimensions in early pregnancy.

Chorionic Gonadotropin↗

PubMedDate not supplied

Critical analysis of intravenous immunoglobulin therapy for recurrent miscarriage.

Critical analysis of intravenous immunoglobulin therapy for recurrent miscarriage An alloimmune abnormality is believed to be the cause of recurrent miscarriage in couples in whom no other cause can be identified. Because of its immunosuppressive properties, intravenous immunoglobulin (IVIG) is used as a treatment for this disorder. The purpose of this study was to determine whether IVIG improves the chance of successful pregnancy in women with recurrent miscarriage by using individual patient data from efficacy trials. Detailed information on each patient enrolled in these trials was obtained to evaluate the efficacy of IVIG and investigate the effect of clinical variability on pregnancy outcome. Data from 125 patients in the IVIG group and 115 patients in the placebo group were available for analysis. Although the number of previous miscarriages and female age were both negative prognostic factors for successful outcome, there was no significant improvement in successful pregnancy or live birth rate with IVIG. Subgroup analyses indicated that timing of IVIG administration may be important. The results of the present study highlight the importance of stratification for known confounders, so that the role of IVIG can be evaluated in more detail. The collective evidence thus far indicates that IVIG does not have a therapeutic effect that is clinically meaningful.

Abortion, Habitual↗

PubMedDate not supplied

Unexplained sporadic and recurrent miscarrage in the new millennium: a critical analysis of immune mechanisms and treatments.

There have been important advances in basic science investigation of mechanisms underlying spontaneous miscarriages which lend support to empirical treatments such as intravenous immunoglobulin G and allogeneic leukocyte immunotherapy. The results from clinical trials of these and other proposed treatments have been problematic. There is only one published meta-analysis of sufficient power and appropriate stratification to qualify as Level 1 evidence, and that deals only with leukocyte immunotherapy. Here we critically review current trials and their flaws, update the meta-analysis, and comment on potential new approaches. Inadequate sample size, better definition of heterogeneity, and proper stratification to minimize the effects of heterogeneity remain as problems. Verification that the experimental or test treatment was active in producing the expected alteration in immunophysiology in the recipient is lacking in most trials; use of stored rather than fresh allogeneic leukocytes appears problematic. Hidden biases that affect trial significance emerge with critical analysis, and the focus on apparent 'high quality' of design in published reports may be misleading. We conclude that there seem to be enough patients to conduct clinical trials of sufficient size to achieve adequate power to test therapies showing promise in pilot studies, but at present, the only Level 1 evidence concerns leukocyte immunotherapy which appears to increase the chance of a live birth if given to appropriate patients.

Abortion, Habitual↗

PubMedDate not supplied

Melatonin and aromatase stimulating activity of human seminal plasma.

Melatonin concentrations and aromatase stimulating activity were determined in human seminal plasma and correlated with sperm density and motility. Aromatase stimulating activity was determined with an in vitro rat granulosa cell system and melatonin by radioimmunoassay. Compared to normal semen, aromatase stimulating activity was lower in azoospermic individuals, while melatonin was higher in oligospermic and azoospermic samples. Aromatase stimulating activity correlated positively with sperm concentrations and a negative correlation was found between melatonin and sperm progression. These findings suggest that low sperm production is associated with low aromatase stimulating bioactivity in seminal plasma; and melatonin may have an effect upon both sperm production and motility.

Adult↗