Follistatin and activin A production by the male reproductive tract

Follistatin is a binding protein for the activin and inhibin family of hormones, regulating their biological activity. In the male reproductive tract, the interaction of these factors is likely to be involved in the regulation of the proliferation of several cell types. We have investigated the presence of follistatin and activin A in seminal plasma using specific immunoassays and have localized follistatin and activin/inhibin subunits in the adult human testis, prostate and seminal vesicle to establish their likely sources. High concentrations of immunoreactive follistatin were present in seminal plasma in normal men (mean 97.9 ng/ml; 1.43 ng/ml in peripheral plasma) and were similar in men with oligo/azoospermia and following vasectomy. Follistatin immunoreactivity was localized to both Leydig and Sertoli cells of the testis, and to epithelial cells of the prostate gland and seminal vesicle, which are likely to be the predominant sources of the hormone in seminal plasma. Activin A was also present in seminal plasma in normal men but was undetectable following vasectomy, thus deriving from the testis. Consistent with this finding, the betaA-subunit was immunolocalized in Sertoli and Leydig cells but was not present in seminal vesicle or prostate gland. The functional significance of the high concentrations of follistatin secreted into seminal plasma by the prostate gland and/or seminal vesicle is uncertain, but they may regulate the biological activity of testis-derived activin A and inhibin B.      

Photocoagulation using the Eisner cone

Thirteen patients with clinical or subclinical retinal detachments were treated with photocoagulation with the aid of a device for scleral depression and the three mirror contact lens. The Eisner cone has proven helpful in achieving clinically white retinal burns at the margins of retinal breaks by displacing subretinal fluid at the time of treatment. Patients selected for treatment had adequate pigmentation for a good photocoagulation response, nearly clear ocular media, and minimal vitreo retinal traction. Extent of retinal detachment was not a determinant, but minimal retinal elevation at break locations proved beneficial. No immediate flattening or adhesion of the retina was seen on release of scleral depression at the time of photocoagulation. White clinical burns remained visible. In 12 of 13 patients the retina was in apposition to the retinal pigment epithelium around the breaks at the first post-treatment examination. The remaining subretinal fluid absorbed in even the most extensive detachment in 2 weeks. One patient with multiple breaks at the equator failed to respond to this technique and required a scleral buckle.     

Electroconvulsive Therapy in the Medically Ill Elderly

Treatment with electroconvulsive therapy (ECT) of medically ill geriatric patients with affective disorders is described. Of 135 patients to whom ECT was administered in 6 years, 55% were over 60 years of age. One-third (45) exhibited cardiovascular (62%), central nervous system (15%), or other medical conditions (22%) increasing the risks of the treatment. Treatment strategies are described.     

Abrogation of adriamycin-induced cardiotoxicity by selenium in rabbits.

Adriamycin-induced cardiomyopathy in rabbits was produced by intravenous injections of the drug with a short therapeutic schedule (3 mg/kg body wt administered as four intermittent doses). Animals receiving selenium supplementation of Adriamycin showed preservation of the normal pattern of the heart histologic picture. The protective effect of selenium was accompanied by increased selenium levels in the plasma and the heart muscle. An eventual interaction between the antitumor effect of Adriamycin and the protective effect of selenium was ruled out by in vitro experiments using the L1210 cell line. Selenium did not abrogate the antiproliferative effect of Adriamycin when the cells were treated simultaneously with both agents. The results from this study indicate that Adriamycin-induced cardiotoxicity could be prevented by selenium if the animals were pretreated with selenium, rather than simultaneous administration of both agents. The mechanism of this effect is not entirely understood.     

Investigation of the binding site of mouse IgG subclasses to homologous peritoneal macrophages.

The binding of mouse myeloma IgG1, IgG2a, IgG2b, IgG1 Fc, IgG2b Fc and a pepsin produced C-terminal subfragment of IgG1 Fc and IgG2b Fc (provisionally identified as pFc') to mouse peritoneal macrophages was investigated. The high affinity cytophilic antibodies belonged to IgG2 subclasses and the binding site of these antibodies was located in the CH3 homology region.     

Heterologous radioimmunossay of monkey alpha-fetoprotein.

Immunoelectrophoresis showed that rabbit anti-human alpha-fetoprotein (AFP) cross-reacts with monkey AFP which was not detectable in the serum from an adult non-pregnant monkey. A heterologous radioimmunoassay of monkey AFP was developed using this antiserum which circumvented the need for purified monkey AFP. The radioimmunoassay is of sufficient sensitivity to measure AFP in maternal and fetal serum and amniotic fluid in the rhesus monkey.