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1.
J Urol ; 164(5): 1694-5, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11025750

RESUMO

PURPOSE: It has been convincingly argued that the increasing incidence of reproductive abnormalities in human males may be associated with increased estrogen exposure during gestation. We documented the expression of estradiol in the syncytiotrophoblast and placenta of males born with cryptorchidism and normal genitalia, respectively. MATERIALS AND METHODS: Tissue from newborn placentas was fixed in glutaraldehyde and embedded in ePON for immunohistological procedures. Cryptorchidism was unilateral in 6 males and bilateral in 1. Semithin histological sections of placental biopsies of these 7 males and 7 randomly selected, normal male placentas were analyzed immunohistochemically with a polyclonal anti-estradiol-17 beta, 6-keto antibody. RESULTS: The weak expression of estradiol in the placentas of normal males was localized predominantly at the basal part of the syncytiotrophoblast in the terminal placental villi. In contrast, all placentas of cryptorchid males had strong expression of estradiol at the basal portion of the syncytiotrophoblast. CONCLUSIONS: The increased expression of estradiol in the syncytiotrophoblast may have an impact on testicular descent.


Assuntos
Criptorquidismo/metabolismo , Estradiol/análise , Placenta/química , Trofoblastos/metabolismo , Criptorquidismo/etiologia , Criptorquidismo/fisiopatologia , Histocitoquímica , Humanos , Recém-Nascido , Masculino
2.
J Urol ; 160(3 Pt 2): 1158-60, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9719299

RESUMO

PURPOSE: Unilateral testicular torsion is common and leads to bilateral testicular injury. Spermiography is abnormal in 70% of patients after testicular torsion. Histological changes in the contralateral testis at the time of torsion have been previously interpreted as the consequence of a predisposing testicular pathology or a noxious effect of the twisted testis. We hypothesized that increased apoptosis in the contralateral testis in unilateral testicular torsion is a consequence of a breakdown in the blood-testis barrier of the twisted testis, which may increase the risk of infertility. MATERIALS AND METHODS: A total of 17 patients 14 to 34 years old (mean age plus or minus standard deviation 20.7+/-6.1) underwent surgery to alleviate unilateral testicular torsion. Mean time from the first symptoms of torsion to surgery was 4.2+/-3.0 hours (range 0.5 to 11). Bilateral testicular biopsy was performed in all patients, and apoptosis was analyzed by terminal deoxynucleotidyl transferase mediated S-deoxyuridine triphosphate nick end labeling. RESULTS: Compared with controls, the incidence of apoptosis was increased in the contralateral testes in all patients. Apoptosis occurred predominantly in spermatocytes, early and late spermatids, and Sertoli's cells. In contrast, spermatogonia, peritubular connective tissue (fibroblasts and myofibroblasts) and endothelial cells seldom underwent apoptosis. Leydig cells were affected less often than spermatocytes. The extent of apoptosis and necrotic changes within the twisted testicle directly correlated with the duration of torsion. CONCLUSIONS: Extensive apoptosis is a phenomenon that occurs regularly in the germinal epithelium of the contralateral testis in testicular torsion. Specifically primary and secondary spermatocytes are predominantly affected. Notably spermatogonia, capillary endothelium, connective tissue and peritubular fibroblasts are rarely involved. A selection strategy has seemingly evolved that precludes the possibility of the perpetuation of genetic mutations. We hypothesize that trauma to the blood-testis barrier initiated by testicular torsion induces the release of apoptotic activating factors (cytokines), which subsequently cause extensive apoptosis in the germinal epithelium of the contralateral testis. Therefore, it is probable that repeat apoptotic episodes may explain the high incidence of infertility in these patients.


Assuntos
Infertilidade Masculina/etiologia , Torção do Cordão Espermático/complicações , Adolescente , Adulto , Humanos , Masculino , Necrose , Torção do Cordão Espermático/patologia
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