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Main Problem: Although the gonadotropins and testosterone are required for normal spermatogenesis, it is believed that local control factors regulate spermatogenesis. For many years these regulatory factors had not been identified. Over the past five years, a number of growth factors have been identified in testis or isolated testicular cell types or secretions. Growth factors are key regulatory molecules which affect cell proliferation, meiosis, and differentiated function. These factors usually act in an autocrine (acting upon the cell which secreted it) or paracine (affecting another cell) manner and thus are involved in intercellular communications., Methods: Growth factor secretion by testicular cell types or testis tissue has been analyzed using a variety of assays measuring cell proliferation in vitro, as well as assays using immunocytochemicals. Growth factor gene expression in testis has been analyzed by Northern blot analysis and in situ hybridization, which gives information concerning the stage and cell specific expression of the gene. Inbred strains of mice with mutations of deletions in a growth factor gene has been used to suggest the function of two specific factors in testicular development and growth., Results: Among the growth factors expressed or secreted by testicular cell types, most are common to some other cell types in the body, such as transforming growth factors alpha and beta, epidermal growth factor, fibroblast-like growth factors, insulin-like growth factors, interleukins, endorphins, inhibin and activin, while others may be more testis specific such as mullerian inhibiting substance (anti-mullerian hormone) and Sertoli cell secreted growth factor.(ABSTRACT TRUNCATED AT 250 WORDS)

Main Problem: fertility data is inadequately assessed by traditional statistical methods for a variety of reasons. First, the principal test of male fertility potential, the Semen Analysis (SA) is a composite of several dissimilar parameters, and the SA and other laboratory tests of fertility potential reflect physiological mechanisms that interact in complex ways. Second, patient data is often fragmented, obtained from multiple sources. Importantly, 2 patients are required for the final result., Methods: Novel and powerful computational method, the neural network, was explored to analyze fertility data. An integrated series of programs was written in the C computer language to implement a back propagation algorithm. A model data analysis system was chosen, predicting the penetration of zona-free hamster ova by sperm (Sperm Penetration Assay (SPA)) and the distance travelled by the farthest swimming sperm (Penetrak Assay) from the SA, for these 2 assays are generally believed by the reproductive medical community to be independent of the SA. The classification accuracy of the neural network was compared to 2 standard statistical methods, linear discriminant function analysis (LDFA) and quadratic discriminant function analysis (QDFA)., Results: A neural network could be trained to correctly predict the Penetrak result in over 80% of assays it had not previously encountered, and another network could predict the SPA outcome in nearly 70%. The neural network was superior to LDFA and QDFA in predicting both assay outcomes (for Penetrak: LDFA = 64%, QDFA = 69%; for SPA: LDFA = 65%, QDFA = 45%).(ABSTRACT TRUNCATED AT 250 WORDS)

We report a case of primary malignant melanoma of the urinary bladder. Exclusion of other sites of melanoma confirmed the primary character of the tumor, and careful histologic examination proved it to be malignant melanoma. Six previously reported cases of bladder melanoma are reviewed. Therapy and prognosis are discussed.

We were interested in determining whether fibrin glue derived from a single human source could be used effectively to produce a sutureless vasovasostomy in the rabbit model. Fifteen rabbits were divided into two groups (7 control, 8 experimental) and underwent vasal transection and reanastomosis by conventional microsurgical suture techniques (control group) and sutureless anastomosis using single source fibrin glue (experimental group). The patency and tensile strength of the anastomoses were compared at four weeks and the anastomotic sites underwent histologic examination. This study demonstrated that a vasovasal anastomosis in the rabbit could be achieved using human single source fibrin glue with patency equivalent to a standard sutured anastomosis. The tensile strength of the glued anastomosis at four weeks was greater than the tensile strength of the sutured anastomosis.

Prolactin and testosterone are synergistic in stimulating growth of the rat prostate. The lateral lobe is more sensitive to this synergism than the ventral and dorsal lobes. To investigate whether prolactin acts directly in the rat prostate or indirectly through another systemic mediator, anterior pituitary grafts (1 mm3) were implanted in the lateral prostate of castrated Sprague-Dawley rats in whom a 0.5 cm or 1.0 cm testosterone-filled silastic tubing was implanted subcutaneously at the same time. Rats were randomly assigned to receive either the pituitary or a muscle chip of similar size grafted beneath the fascia lateral to the lateral prostate. Twenty-one days later, serum prolactin levels were not elevated in pituitary-grafted animals and were not significantly different from those in muscle-grafted rats. The mean lateral prostate weight on the grafted side in pituitary-implanted rats with 1.0 cm testosterone tubing was 43% heavier than either that of the contralateral side or the corresponding weights in muscle-implanted rats. In pituitary-implanted rats with 0.5 cm testosterone tubing, the mean lateral prostate weight on the grafted side was 60% heavier than either that of the contralateral side or that of the corresponding weights in muscle-implanted rats. The weight of the ventral and dorsal lobes of the prostate was not significantly affected by the presence of pituitary grafts in one of the lateral lobes. The local effect of prolactin on the lateral prostate was further demonstrated by an overall decline in tissue concentrations of dihydrotestosterone in the grafted side. These results provided evidence to indicate that there was a direct effect of prolactin on growth of the lateral prostate in rats.

A ureterocutaneous fistula developed in a patient after nephrectomy for pyohydronephrosis in a kidney with vesicoureteral reflux. Endoscopic injection of polytetrafluoroethylene (Teflon) paste at the ureteral orifice prevented further reflux and cured the ureterocutaneous fistula.

Artifactual and nonartifactual evidence from the lacustrine shores of the Chalco-Xochimilco Basin suggest the existence of fully sedentary human communities in the Basin of Mexico from at least the sixth millennium B.C.