Observations on dissected tubules, fked in Carnoy, stained with hematoxylin and mounted "in toto" revealed that there were five distinct classes of type A spermatogonia. The type AI found in stages 11-VIII of the cycle of the seminiferous epithelium had round, pale-stained nuclei, typically arranged in linear clusters of four or eight along the tubular wall. They all divided at stage IX to produce type A2 cells. These in turn divided at stage XI1 to produce type As spermatogonia. The type A2 and As cells had large ovoid nuclei containing globular masses of deeply stained chromatin and were randomly distributed in the space between Sertoli nuclei. The type A3 spermatogonia divided a t stage XIV to produce type A4 cells. These had smaller nuclei, sometimes lobulated, containing more deeply stained chromatin granulation, free in the nucleus or adhering to the nuclear membrane. They divided in stage I of the cycle to yield two classes of spermatogonia: intermediate type and new type Al. Hence, type Al-type A4 spermatogonia were considered as '
In order to evaluate the effects of the exposition to continuous chronic hypobaric hypoxia (CCHH) and intermittent chronic hypobaric hypoxia (ICHH) on testis histology and on oxidative metabolism of spermatogenic cells (SC), male rats were exposed to a 4600-m simulated altitude (PO2: 89.6 mmHg). After 60 days, ICHH and CCHH groups presented a significant decrease in testicular mass, an increase in interstitial space, a decrease in height of the seminiferous epithelium, depletion of cellular elements, vacuolization in epithelial cells and folding of the basal membrane. Round spermatids from animals exposed to CCHH presented a significant decrease in energy-dependent cell shape changes. Round spermatid mitochondria of CCHH rats seem to be limited in their ability to handle reducing equivalents. These mitochondria also appear to be uncoupled under basal conditions. Round spermatids from CCHH rats evidence large oxygen consumption (QO2) insensitive to inhibition by cyanide, a process that could be partly related to lipoperoxidation. Thus, exposure of male rats to CCHH and ICHH induced evident changes in testicular morphology and loss of spermatogenic cells, in all stages of the spermatogenic cycle. This post-meiotic spermatogenic cell loss in the testis correlated well with metabolic changes in round spermatids that evidenced a strong metabolic stress in these cells.
With approximately 90 million cases annually, infection with Chlamydia trachomatis is the most prevalent sexually transmitted bacterial disease in the world. Considering that these infections are often asymptomatic and cause major complications like acute pelvic inflammatory disease, ectopic pregnancy, infertility or infant pneumonia, the estimated costs for diagnosis and treatment in the USA amounts to 2.2 million US dollars for each 500 cases. Therefore, there is a high need for correct, quick and cost-effective diagnosis and treatment of this urogenital tract infection. New innovative therapies provide good results with regard to efficacy and patients' compliance. The success rates of treatments are at least 95%. However, the occurrence of antibiotic resistance should not be ignored and new treatment schemes must be developed. The state-of-the-art of diagnosis and treatment of chlamydial infections as well as the pathophysiology is discussed in this review. In conclusion, infections with C. trachomatis is an important public health problem, especially in third world and developing countries, and more socio-economic studies linking secondary prevention of chlamydial infections, infertility and adverse pregnancy outcome are needed to understand more of its aetiology. In addition, diagnosis and treatment should be improved. Data in men revealed that past infections but not present infections are more related to male infertility. There is still controversial results. In future studies, function of the seminal vesicles and evaluation of the antioxidant capacity should be taken into account when role of C. trachomatis infection on male fertility is assessed.
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