The effect of vasectomy on pituitary-gonadal function in men

The testosterone concentration in allantoic fluid between 90 and 150 days of gestation in cattle can be used to determine the fetal sex; values were 442 +/- 20-3 (S.E.M.) pg testosterone/ml for males fetuses and 215 +/- 8-2 pg/ml for female fetuses.     

Diagnosis and pathophysiology of paradoxical embolism

A review of the experience with 134 consecutive patients with germinal cell testicular neoplasia indicates that definitively accurate staging of the malignancy at presentation is the single most important prognostic factor. Nearly two-thirds of the patients with all types of germinal malignancies survived or died of other causes and the highest survival rates were seen among patients with earlier stages of seminoma. In recent years patients with all types of germinal malignancies of the testis have been treated by radical retroperitoneal lymphadenectomy with enhancement of survivals. Patients with seminoma and non-seminomatous tumors exhibited increased survival rates with node dissection. In 66 consecutive lymphadenectomies the complication rate was less than 14 per cent, with only 1 death related to the operation. Retroperitoneal lymphadenectomy not only affords therapeutic advantage but also provides an opportunity for accurate surgical staging of disease and allows for rational decision relative to additional treatment, radiation therapy or chemotherapy.     

Gonadoblastoma: histologic, ultrastructural, and histochemical observations in five cases

In this series of gonadoblastomas it appeared that the germ cells were the motivating force underlying either tumor proliferation or regression. The ultrastructural morphology confirmed the presence of undifferentiated gonadal cells with active steroid synthesis by the interstitial cells. The Call-Exner-like bodies which showed extensive calcification were composed of basement membrane material containing a sulfated mucosubstance. A histochemical comparison with the noncalcifying Call-Exner bodies of a granulosa-cell tumor differed only in their glycoprotein content. The calcium deposits were identified as oriented hydroxyapatite crystals by electron diffraction, and it is proposed that the basement membrane material serves as a nucleation site for calcification. High serum testosterone levels were correlated with the presence solely of interstitial cells in one case. The finding of a gonadoblastoma without the presence of a Y chromosome contradicts earlier proposals concerning the requirement of a Y chromosome for germ cell proliferation.     

Medical and surgical therapy in diverticular disease: a comparative study

The course of 132 patients with documented acute diverticulitis was analyzed: 99 patients treated medically and 33 patients treated surgically were followed for an average of 9.2 years. Seventy-three per cent of the medical group and 79% of the surgical group had no further symptoms or hospital admissions as a result of their diverticular disease once they were recovered from the acute episode. For three-quarters of the patients, therefore, acute diverticulitis occurred as a single episode that responded to either medical or surgical management. Considering the morbidity and cost to the patient, the treatment of the patient recovered from acute diverticulitis should be medical, with operation reserved for complications.     

The effect of (2'-5') and (3'-5') phosphodiester linkages on conformational and stacking properties of cytidylyl-cytidine in aqueous solution

Conformational properties of (2'-5') and (3'-5') CpC have been determined by proton magnetic resonance spectroscopy at 220 MHz. The ribose ring structures are predominantly 3E with the exception of the ring from the 2'-phosphate fragment of C(2'-5')pC which exhibits an 2E pucker. Bases are oriented anti with respect to the ribose and the conformations about C4'-C5', C5'-O5', C3'-O3' (C2'-O2') are gg, g'g', and g+ in equilibrium g-, respectively. The dimers exist as mixtures of stacked (g+g+ and g-g- about the P-O(C) bonds) and unstacked species at 20 degrees C. Stacking is estimated to be 35% in both dimers.     

Interaction of short chain and long chain fatty acid phosphoglycerides and bile salts with prothrombin

An equimolar mixture of phosphatidylserine and (dioleoyl) phosphatidyl-ethanolamine could substitute for brain cephalin preparations in the single stage prothrombin assay. However, no clot promoting activity was observed on the addition of any of the individual long chain fatty acid-containing phospholipids. Short chain fatty acid-containing phospholipids, such as diheptanoylphosphatidylcholine, diheptanoylphosphatidylethanolamine, diheptanoylphosphatidic acid, and dihexanoylphosphatidylcholine, or dihexanoylphosphatidylethanolamine were inhibitory under all conditions studied. Similar effects of these two general classes of phospholipids were observed in a two-stage thrombin generation system, in which a mixture of bovine Factor Xa, Factor Va, and Ca2+ were interacted with prothrombin. In the presence of 25 mM Ca2+, dioleoylphosphatidic acid or brain phosphatidylserine alone, and with other long chain phospholipids, formed complexes with bovine plasma prothrombin. On the other hand, dioleoyl-, diheptanoyl- or dihexanoylphosphatidylcholine under comparable conditions showed no binding to prothrombin. There appeared to be a small degree of binding of diheptanoylphosphatidic acid to prothrombin, but it was insufficient to cause any significant change in apparent molecular weight of prothrombin. A mixture of prothrombin, Factor V, diheptanoylphosphatidic acid/diheptanoylphosphatidylcholine and Ca2+ eluted in the void volume of Sephadex G-200, but showed a much reduced coagulant activity. Though a net negative charge on the phospholipid surface is required for phospholipid-protein interactions, this does not necessarily promote coagulant activity. Bile acids and bile salts, such as cholic acid, deoxycholic acid, taurocholic acid, glycocholic acid, lithocholic acid and dehydrocholic acid, exerted varying levels of stimulation on the prothrombin assay and thrombin generation system, but were not as effective as the phospholipids. Interestingly, no interaction of these bile acids or salts with prothrombin was noted in the presence of Ca2+. The results of these experiments suggest that negatively charged micelles per se are not sufficient for binding alone and that other chemical and physical characteristics of phospholipids are of prime importance.     

Inhibition of insulin degradation by nonsuppressible insulin-like activity

Nonsuppressible insulin-like activity, provided by three sources, was evaluated for its effect on the proteolytic degradation of insulin utilizing insulin protease obtained from rat liver homogenate as well as liver cell membranes. All three preparations of nonsuppressible insulin-like activity were found to be competitive inhibitors of insulin degradation. In addition human plasma was fractionated yielding an acetone precipitate which was found to have nonsuppressible insulin-like activity and to be a competitive inhibitor of insulin protease.