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Biomedical subjects

W L Herrmann

Publications and source records attributed to W L Herrmann.

At least 37 records · Page 2Linked to original sources
PubMed1983

Inhibition of denuded mouse oocyte meiotic maturation by forskolin, an activator of adenylate cyclase.

Forskolin, a diterpene that activates rapidly adenylate cyclase activity in several somatic cell systems, prevents spontaneous meiotic maturation of denuded mouse oocytes (ED50 of inhibition approximately 2.5 microM), unlike cholera toxin. The oocyte is sensitive to the action of forskolin during the period preceding germinal vesicle breakdown (GVBD). Washing of the cells abolishes the effect. The diterpene potentiates the inhibitory effect of iso-butyl-methyl-xanthine (IBMX), a phosphodiesterase inhibitor, and it increases cAMP concentration in the oocytes. These findings not only confirm the antagonistic effect of cAMP on the first step of meiosis reinitiation (GVBD) in mammalian oocytes, but also provide the first demonstration of a functional adenylate cyclase system in mammalian oocytes upon which regulatory signals may act.

1-Methyl-3-isobutylxanthine↗
PubMed1983

Human seminal plasma contains a protein that shares physicochemical, immunochemical, and immunosuppressive properties with pregnancy-associated plasma protein-A.

Pregnancy-associated plasma protein-A (PAPP-A) was detected by RIA in human seminal plasma. This was not due to interference with proteases or binding to seminal plasma proteins, since immunoreactivity was not affected by treatment with protease inhibitors, and the elution of [125I]PAPP-A was not altered by preincubation with seminal plasma. The major component of the seminal plasma PAPP-A coeluted with pure PAPP-A or plasma PAPP-A from pregnant and nonpregnant women. In the RIA, serial dilutions of seminal plasma gave parallel displacement curves to pregnancy plasma. Removing PAPP-A-like material from seminal plasma by adsorbtion to heparin-Sepharose reduced the inhibitory effect of seminal plasma on phytohemagglutinin-induced lymphocyte transformation. The source of seminal plasma PAPP-A-like immunoreactive material remains to be elucidated, but it is unlikely to be the testis, since PAPP-A levels in semen of vasectomized men were similar to those in nonvasectomized men.

Female↗
PubMed1983

Circulating levels of pregnancy proteins and depression of lymphoblastogenesis during pregnancy.

Plasma was obtained from 287 normal pregnant women at different times of gestation. Alpha-foetoprotein (AFP), human chorionic gonadotrophin (hCG), human placental lactogen (hPL) and pregnancy associated plasma protein-A (PAPP-A) were measured by radioimmunoassay. The capacity of those plasmas to inhibit phytohaemagglutinin (PHA) induced lymphocyte transformation was also tested. Between the 7th and the 12th week, pregnancy plasma has a relatively small inhibitory effect on lymphoblastogenesis. Plasmas taken between the 13th week and term pregnancy inhibit much more lymphocyte transformation. The factor which increases this inhibition is unknown. None of the proteins measured were significantly correlated with the inhibitory effect. Two explanations are proposed: either AFP, hCG, hPL and PAPP-A are not responsible for the in vitro inhibition of lymphoblastogenesis or else these factors exert a combined effect so that the concentration of each protein taken separately cannot account for the overall inhibitory effect observed with pregnancy plasma.

Female↗
PubMed1975

Association of exogenous estrogen and endometrial carcinoma.

To determine the association between the incidence of endometrial cancer and the use of estrogen in menopausal and post-menopausal women, we retrospectively compared 317 patients with adenocarcinoma of the endometrium with an equal number of matched controls having other gynecologic neoplasms; 152 patients used estrogen, as compared to 54 of 317 controls. Thus, the risk of endometrial cancer was 4.5 times greater among women exposed to estrogen therapy. When estrogen use was adjusted for concomitant variables such as obesity, hypertension, diabetes, parity, referral pattern, age at diagnosis, year of diagnosis and other gynecologic neoplasms, the magnitude of the increased relative risk was associated with several of these variables, and was highest in patients without obesity and hypertension. Exogenous estrogen therapy is associated with an increased risk of endometrial carcinoma, but this increased relative risk is less apparent in patients with physiologic characteristics previously associated with an increased risk.

Adenocarcinoma↗
PubMed1975

Monitoring health care.

Health risk determinants in obstetrics and gynecology are readily obtainable from state birth records. This study demonstrates the manner in which these determinants may be used to assess health care delivery and monitor its progress. The over-all problem is quite complex. Some parameters are interrelated, while others are not. In addition, any specific parameter may be causally related to many different antecedents, acting singly or in combination. Hence, one must take care not to generalize about deficiencies in our health care systems and thereby propose simplistic, unworkable solutions. However, the study does clearly identify certain specific areas of risk which deserve greater attention than they have hitherto received from health care officials, physicians, and responsible citizens. We believe that the approach outlined in this paper offers a means to achieve unbiased, ongoing monitoring of health care, which may, in turn, be used in attempts to improve the delivery of health services.

Abortion Applicants↗
PubMed1975

Perturbations of the human menstrual cycle by oxymetholone.

The luteolytic activity of oxymetholone, and anabolic steroid, has been evaluated in 10 women. Administration early in the follicular phase of the cycle inhibited ovulation and prolonged the duration of the cycles in 2 of 3 subjects, but treatment beginning on Day 10 (3 subjects) did not prevent ovulation, although subsequent plasma progesterone concentrations were reduced. Treatment after ovulation (4 subjects) suppressed progesterone levels by 50 to 80 per cent and shortened cycle length by 6 to 8 days. Side effects were weight gain and bromosulfophthalein retention. The most likely mechanisms producing these perturbations are the inhibition of luteinizing hormone release early in the cycle and, later, inhibition of progesterone biosynthesis.

Administration, Oral↗