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Biomedical subjects

A Lightman

Publications and source records attributed to A Lightman.

29 records · Page 2Linked to original sources
PubMed1987

Outcome of in vitro fertilization in women with low response to ovarian stimulation.

The occurrence of low-response (LR) cycles (defined as peak estradiol levels less than 300 pg/ml) in an in vitro fertilization program using a 3 ampule/day human menopausal gonadotropin regimen were retrospectively reviewed. LR occurred in 51 of 564 patients (9%). The LR serum estradiol levels were categorized into four different patterns that were further analyzed for outcome in these initial cycles, as well as for their predictive value of response in subsequent in vitro fertilization cycles. Changing the stimulation protocol to a combination of clomiphene citrate and human menopausal gonadotropin did not improve the ovarian response in this group of LR patients, and their chance to complete a subsequent normal-response treatment cycle was 32%. Suggestions are made to predict outcome and govern management of women with previous LR cycles.

Adult↗
PubMed1987

In situ hybridization identifies renin mRNA in the rat corpus luteum.

All components of the renin-angiotensin system (RAS), including angiotensinogen messenger RNA (mRNA), renin-like activity (RLA), renin mRNA, angiotensin II (A II) immunoreactivity and angiotensin converting enzyme, have been found in the whole rat ovary and A II receptors have recently been localized to ovarian follicles. Our study was designed to test further which part of the ovary can produce renin. Renin mRNA was detected in the gonadotropin-stimulated rat's corpus luteum using in situ hybridization histochemistry techniques. No positive signal was detected in theca or granulosa cells. These results indicate ovarian renin gene expression in rat luteal cells, where the renin molecule is probably produced, and support our concept of an intrinsic ovarian RAS.

Animals↗
PubMed1986

Angiotensin II-like immunoreactivity in human ovarian follicular fluid.

Human ovarian follicular fluid (hFF) has angiogenic activity, although the causative factors are unknown. We recently found that hFF contains renin activity which converts renin substrate to angiotensin I (AI). Since the enzymatic cleavage product of AI, angiotensin II (AII), is a potent stimulator of new vessel formation, we have examined Sephadex G-25 column fractions of hFF and extracted hFF and plasma from individual patients for AII-like immunoreactivity (AII-IR). Eluent fractions from Sephadex G-25 column chromatography of hFF had significant AII-IR which eluted in the same fractions as synthetic AII. Individual, extracted FF samples contained approximately 10 times higher levels of AII-IR than extracts of plasma from the same patients. Serial dilutions of the Sephadex column fractions and extracted FF and plasma inhibited binding of 125I-AII to rabbit anti-AII serum in a manner parallel to the inhibition caused by synthetic AII, indicating that the detected immunoreactivity was not due to non-specific assay interference. In summary, the results indicate the presence of significant AII-like immunoreactivity in hFF. AII may now be considered as a potential mediator of the angiogenic activity present in hFF and may play an important paracrine and/or autocrine role in physiologic events in the ovary.

Angiotensin II↗
PubMed1986

Use of the serum copper/zinc ratio in the differential diagnosis of ovarian malignancy.

We measured copper and zinc in serum (n = 82) and tumor tissue (n = 41) from women with a palpable pelvic mass, admitted for suspected ovarian tumor. In serum, copper was increased and zinc decreased in the group (n = 40) subsequently proven to have a malignant ovarian tumor. The mean copper/zinc ratio in this group was 2.30 (SD 0.41), significantly (p less than 0.001) higher than for the benign group (n = 42), 1.43 (SD 0.22). In tumor tissue the concentrations of copper and zinc followed the same pattern, the copper/zinc ratio being significantly (p less than 0.001) higher in the malignant (0.158, SD 0.065) tumors than in the benign tissue (0.093, SD 0.04). We conclude that the Cu/Zn ratio in serum reliably (specifically) indicates the presence of advanced ovarian malignant tumor. The decreased concentrations of zinc and the increased concentrations of copper in serum do not seem to result from a shift of zinc into or release of copper out of the malignant tumor tissue.

Copper↗
PubMed1983

The diagnostic value of serum copper/zinc ratio in gynecological tumors.

Serum copper levels (SCu) and serum zinc levels (SZn) were determined on admission in 73 women hospitalized for suspected gynecological tumor. Twenty-five of the women were subsequently found to have malignant tumor, while 48 had benign growths. The serum Cu/Zn ratio of the malignant group (2.13 +/- 0.53) was significantly (p less than 0.001) higher than that of the benign group (1.45 +/- 0.25). A good correlation was established between the Cu/Zn ratio and the stage of the malignant tumor. Serum copper level showed a linear correlation (R = 0.878) with serum ceruloplasmin values. These results indicate that the serum Cu/Zn ratio may be used as a valuable predictor of the presence of malignant gynecological tumor and its stage.

Ceruloplasmin↗
PubMed1980

Zinc concentration in gravida's serum and amniotic fluid during normal pregnancy.

Zinc concentration was determined in maternal serum and amniotic fluid during normal pregnancy. The nonpregnant zinc concentration in the serum of about 110 micrograms% decreases gradually during pregnancy to about half the normal level. Amniotic fluid zinc concentration shows a slight decrease and remains nearly constant until the 34th to 36th week of gestation, and then increases sharply (statistically significant) reaching the highest level at 40-42 weeks from the last menstrual period. The maternal-fetal metabolism of zinc, the various factors effecting zinc levels in maternal serum and amniotic fluid during pregnancy have been discussed in view of our results. These may serve as data base for further studies on the role of zinc in normal and pathological human pregnancies.

Amniotic Fluid↗
PubMedDate not supplied

Male gonadal function in survivors of childhood Hodgkin and non-Hodgkin lymphoma.

The aim of this study was to investigate the impact of therapy on long-term gonadal function of young people cured of childhood lymphomas and to assess whether a prepubertal state during the treatment protects the gonads from chemotherapy and/or radiotherapy late effects. Clinical evaluation, semen analysis, and endocrine status were studied in 20 survivors of childhood lymphomas. Five patients received Inverted Y radiotherapy, 2320 cGy (1550-4000); all 20 received chemotherapy as follows: MOPP/ABVD protocol, 9 patients; COMP protocol, 5 patients; MOPP protocol, 3 patients; other protocols, 3 patients. Semen analysis results were as follows: normal values, 4/20 patients; oligospermia, 8/20 patients; azoospermia, 8/20 patients; FSH above normal level, 10/20 patients; 4/5 who received Inverted Y irradiation were azoospermic and 1 was severely oligospermic. Treatment damage to the testis involves tubular germinal elements. Radiotherapy and chemotherapy combinations that included nitrogen mustard or cyclophosphamide were associated with high rates of oligospermia and azoospermia. MOPP/ABVD combination did not have a significant better outcome of sperm counts compared to MOPP alone. Age at chemotherapy did not correlate with the sperm count; hence a prepubertal state did not protect the gonad from the late effects of treatment.

Antineoplastic Combined Chemotherapy Protocols↗