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The postnatal maturation of the epithelium and tubule wall of efferent tubules in the rat was investigated by light and transmission electron microscopy, from birth to 50 days of age, when sperms were released from the seminiferous tubules and appeared in the genital duct. At the end of the first week of life, an endocytotic apparatus is differentiated in the epithelial cells. During the third week of life, efferent tubules developed specializations for the transport of sperms and fluids, namely the appearance of ciliated elements interspersed among the principal cells of the epithelium, and differentiation of myoid elements in the tubule wall. The appearance of specializations related to endocytosis and fluid transport across the epithelium preceded the canalization of the seminiferous cords which, in fact, is reported to appear at the end of the second week of life in the rat, along with the initial secretion of testicular fluid. This suggested that the maturation of efferent tubules is not triggered by the passage of testicular fluid, as surmised for the postnatal differentiation of caput epididymis. The postnatal maturation of efferent tubules was almost complete 35 days after birth. The appearance of sperms in the genital duct of 50-day-old animals was not associated with any remarkable structural change.

This study explores the use of a modified cloze procedure in assessing a child's oral comprehension. It encourages the speech pathologist and special educator to use this procedure in a diagnostic and therapeutic context with children who are developmentally delayed. Its routine use broadens the role definition of the educator as a skilled evaluator and trainer in grammatical decoding and subsequent vocabulary development.

The biochemical and functional similarities between skeletal muscle sarcoplasmic reticulum and the microsomal Ca2+ store of nonmuscle cells are discussed. It is shown that antibodies raised against two characteristic proteins of sarcoplasmic reticulum, Ca2+ ATPase and calsequestrin, recognize similar proteins in nonmuscle cells. The subcellular distribution of these two antigens was studied at the subcellular levels in ultrathin cryosections. In a variety of cell types these two proteins were found to be localized in small membrane enclosed vesicles, apparently distinct from other known organelles. We propose that these newly recognized structures (calciosomes) represent the functional equivalent of sarcoplasmic reticulum in nonmuscle cells.

IgG, IgA, IgM and lysozyme levels were determined in whole unstimulated saliva from ten children aged seven-nine years. IgA levels were significantly higher (p less than 0.05) in caries-susceptible subjects when compared with the caries-free ones. High levels of IgG seemed to correlate with a high DMF score. No correlation was found between lysozyme levels and DMF score.

500 infertile patients (250 with and 250 without left side varicocele) and 33 fertile men were evaluated as far as seminal parameters and the hormonal status were concerned. Sperm motility was constantly lower in infertile patients also when infertile group was compared to fertile one with the same sperm density. Serum testosterone levels were lower in infertile groups when compared to fertile men, and this confirms the existence of an androgenic deficit as a common finding in infertility associated or not to varicocele. FSH and LH increased (p less than 0.001) when sperm density dropped to less than 5 X 10(6) spermatozoa/ml. A negative correlation was found between both gonadotropins and sperm count (p less than 0.001), also after exclusion of azoo- and oligozoospermic (less than 5 X 10(6) spermatozoa/ml) patients (p less than 0.01). Gonadotropins were moreover tightly correlated between each other (p less than 0.001). Our data suggest that both gonadotropins are tightly tuned with sperm output and thus with the spermatogenic potential.

A quantitative analysis of Leydig cells was performed in 23 testicular biopsies of men with left varicocele and sperm count ranging from zero to 95,000 sperm/mm3. The oligozoospermic patients had more Leydig cells and higher FSH and LH serum levels than the patient group with more than 10,000 sperm/mm3. The Leydig cell density appeared tightly correlated (p less than 0.01) with the serum level of LH. In oligozoospermic subjects, an altered Leydig cell function could trigger an increased LH secretion; this seems likely to be responsible for the stimulation of interstitial cells resulting in an exaggerated recruitment of mature Leydig cells from their precursors. The comparative analysis of left and right testes failed to show differences in Leydig cell density and spermatogenesis in normozoospermic and oligozoospermic patients. This suggests that the two testes are equally involved by a possible, although unknown, detrimental effect of left side varicocele.

The ultrastructural aspects of the germinal epithelium of 10 infertile men affected by maturative arrest of spermatogenesis were studied. We noted an increased number of malformed germinal cells. Marginal nuclear vescicles were present in spermatogonia of patients affected by spermatogonial arrest. The few spermatid present in the germinal epithelium of the patients affected by a spermatidic arrest presented changes of the nuclear condensation, the acrosome, and the tail. The Sertoli cells presented an immature aspect of the nucleus and changes of the "mantle". A possible correlation between the Sertoli cells changes and the altered spermatogenesis was proposed.

The immunoreaction for acrosin in different morphological types of human spermatozoa was evaluated by light microscopy in the semen of 68 male partners of infertile couples. The antigen had a cup-shaped distribution in the anterior region of the head in normal spermatozoa, and in those with an isolated abnormal mid-piece or tail. On the contrary acrosin was absent, or it did not show a cup-shaped immunostaining, in most spermatozoa with malformed heads with the exception of those with a large oval form. The assessment of immunoreaction for acrosin and of vitality of different morphological types of spermatozoa in the same ejaculates, suggested that the antigen was intrinsically absent in abnormal-headed but vital spermatozoa. It is concluded that an inherent lack, or an abnormal synthesis of acrosin during spermatogenesis is associated to the abnormal development of the spermatozoa head.

Calciosomes are small cytoplasmic vacuoles identified in various nonmuscle cell types by their content of protein(s) similar to calsequestrin (CS), the Ca2+ storage protein of the muscle sarcoplasmic reticulum (SR). These entities have been interpreted as the "primitive" counterpart of the SR, and suggested to be the organelle target of inositol-1,4,5-triphosphate action (Volpe, P., K. H. Krause, S. Hashimoto, F. Zorzato, T. Pozzan, J. Meldolesi, and D. P. Lew. Proc. Natl. Acad. Sci. USA. 85:1091-1095). Immunoperoxidase and immunogold experiments carried out in both thick and ultrathin cryosections of rat hepatocytes and pancreatic acinar cells by using antimuscle CS antibodies revealed a specific labeling widely distributed in the entire cytoplasm, while nuclei were negative. Individual calciosomes appeared as small (105 nm) membrane-bound vacuoles intermingled with, and often apposed to ER cisternae and mitochondria. Other calciosomes were scattered in the Golgi area, in between zymogen granules and beneath the plasma membrane. The cumulative volume of the CS-positive organelles was measured to account for the 0.8 and 0.45% of the cytoplasm in liver and pancreas cells, respectively. The real total volume of the calciosome compartment is expected to be approximately twice as large. In hepatocytes, structures similar to CS-positive calciosomes were decorated by antibodies against the Ca2+ ATPase of muscle SR, while ER cisternae were not. By dual labeling, colocalization was revealed in 53.6% of the organelles, with 37.6% positive for the ATPase only. CS appeared preferentially confined to the content, and the Ca2+ ATPase to the contour of the organelle. The results suggested a partial segregation of the two antigens, reminiscent of their well-known segregation in muscle SR. Additional dual-label experiments demonstrated that hepatic calciosomes express neither two ER markers (cytochrome-P450 and NADH-cytochrome b5 reductase) nor the endolysosome marker, luminal acidity (revealed by 3-[2,4-dinitroanilino]-3'-amino-N-methyl dipropylamine). Calciosomes appear as unique cytological entities, ideally equipped to play a role in the rapid-scale control of the cytosolic-free Ca2+ in nonmuscle cells.