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PubMed1990

Estrogen and androgen production rates in two brothers with Reifenstein syndrome.

Defects of the androgen receptor in 46,XY individuals cause aberrant virilization that varies from a female phenotype to men with minor defects. More severely affected individuals also develop gynecomastia associated with enhanced estradiol secretion by the testis. However, the degree of breast development does not correlate with the rate of estrogen production, leading us to propose that feminization is a function of the degree of androgen resistance as well as the rate of estrogen formation. To test this hypothesis we measured estrogen and androgen formation in two brothers with perineoscrotal hypospadias and severe gynecomastia (the Reifenstein phenotype) due to a mutation that impairs androgen receptor function. Rates of estradiol production (60 and 70 micrograms/day) were elevated, but were not as high as in previously studied men with a similar phenotype. We conclude that the variable degree of feminization in this disorder cannot be explained by androgen resistance alone.

Adult↗
PubMed2005

[Is fetal testis in danger?].

Estrogens are classically known to play a major role in female reproduction, but there is now compelling evidence that they may also be involved in the regulation of male reproductive function. In humans, a decrease in sperm count and an increase in the incidences of testicular cancer, cryptorchidism and hypospadia have been observed in many countries over the last 50 years. Male reproductive alterations were also observed in wildlife. Such male reproductive disorders have been attributed to the increase in concentration of xenobiotics, and of xenoestrogens in particular, in the environment and in food. Epidemiological, clinical and experimental studies have suggested that excessive exposure to estrogens during fetal/neonatal life can lead to reproductive disorders in adulthood. Using an in vitro model, we showed that estrogens directly affected the development of the fetal testis. Lastly, we clearly demonstrated that the fetal and neonatal testis is very sensitive to estrogens since the invalidation of estrogen receptor alpha leads to an increase of steroidogenesis and the invalidation of estrogen receptor beta enhances the development of the germ cell lineage in the male.

Estrogens↗
PubMed1987

Testicular cancer risk in boys with maldescended testis: a cohort study.

Testicular maldescent is considered as a predisposing condition for development of testicular malignancy. Male subjects with a history of cryptorchidism have been suggested by some authors to have a 40 to 50 times increased risk of testis cancer. However, the magnitude of this risk is a point of considerable disagreement. Therefore, we studied the records of 506 consecutive patients hospitalized for maldescended testis from January 1949 to December 1960. Testis cancer developed in 6 patients, which when compared to the 1.3 expectant Danish incidence rate, yielded a statistically significant relative risk of 4.7 (95 per cent confidence interval 1.7 to 10.2). Thus, our study confirmed that male subjects with a history of testicular maldescent have an increased risk for testis cancer, although the magnitude of this risk was lower than suggested previously.

Adult↗
PubMed2005

In utero and lactational exposure to TCDD; steroidogenic outcomes differ in male and female rat pups.

TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) has a potency to induce decreased fertility and structural reproductive anomalies in male and female mammals. While the activity profile of sex steroid hormone production distinctly differs in developing males and females, we wanted to analyze sex-specific effects of TCDD introduced in utero and via lactation on gonadal steroidogenesis and gonadotropin levels in male and female rat infant pups. One oral dose of TCDD (0, 0.04, 0.2, or 1.0 microg/kg) was given to dams on gestational day (GD) 13. Plasma testosterone, estradiol, progesterone, follicle stimulating hormone (FSH), luteinizing hormone (LH), and gonadal mRNA levels for steroid acute regulatory protein (StAR), cytochrome P-450 cholesterol side-chain cleavage (P450scc), 3beta-hydroxy-steroid-dehydrogenase/Delta(5)-Delta(4) isomerase type I (3beta-HSD1), P-450 17alpha-hydroxylase/17,20-lyase (P450-17alpha), and cytochrome P-450 aromatase (P450arom) were determined on postnatal days (PND) 10-16. TCDD 1.0 mug/kg reduced body weights but did not affect relative testis weight or alter testicular and ovarian histology. Plasma estradiol levels in dams and female pups were reduced on PND 14 and 16. Progesterone levels remained unaltered, and FSH levels were increased in female pups. In males, testosterone levels were elevated on PND 10. Gonadal mRNA levels for StAR and steroidogenic enzymes increased during the postnatal growth. TCDD caused no changes in relatively low testicular mRNA levels. However, significant reductions in StAR and P450arom mRNA levels were seen in PND 14 ovaries, and P450arom activity was decreased in isolated ovarian follicles. We conclude that developing testis and male gonadotropin secretion are resistant to TCDD-induced toxicity. In female pups, reduced estradiol, ovarian P450arom expression and enzyme activity levels, and elevated FSH levels may have a role in the development of ovarian dysfunction reported in TCDD-exposed females.

Abnormalities, Drug-Induced↗
PubMed1977

Epidemiology of cancer of the testis in upstate New York.

We collected data on the 434 individuals reported with cancer of the testis to the New York State Tumor Registry, 1960-64, from upstate New York. We compared these with the 410 members of a random sample of the upstate population interviewed from 1959 to 1962. A high risk of developing cancer of the testis was associated with professional occupations, native-born parentage, rural residence, and having been married, especially while young. These findings paralleled some other studies, as well as our earlier inquiry. Each of these factors carried a higher risk even when considered in the context of the other traits, and risk increased with an increase in the number of characteristics possessed.

Adolescent↗
PubMed2000

Comparative studies of fertility and histologic development of contralateral scrotal testes in two rat models of unilateral cryptorchidism.

Fertility and the development of the contralateral scrotal testis in patients with unilateral cryptorchidism (UCO) remain controversial. This study investigated these controversies in two different UCO rat models using 43 Wistar King A rats. The animals were divided into three groups: I: an endocrinologic model of UCO was obtained by injecting pregnant dams with flutamide 100 mg/kg per day on days 15-17 of gestation (n = 12); II (n = 21): a mechanical model of UCO was obtained by extra-abdominal fixation of the gubernaculum in the neonatal period, III (n = 10): non-treated rats were used as controls. At the age of 90 days, 5 rats from each group were segregated into individual cages and housed with two virgin adult females for 2 weeks. The occurrence of pregnancy and litter sizes were counted in order to study fertility. All the animals were then weighed and killed. The occurrence of testicular descent, growth of the external genitalia, and epididymal development were examined. Morphologic and histologic evaluations were performed in the cryptorchid and contralateral testes. In the endocrinologic model (group I) the 10 female rats failed to show any offspring (0%), while in the mechanical model (group II) 9 out of 10 rats had offspring (90%, P < 0.001); 10 out of 10 control rats showed offspring. All of the rats in groups I and II had UCO, and the undescended testes were located in the superficial inguinal position, while the contralateral and control testes descended into the scrotum. Hypospadias and a small epididymis were frequently noted in the flutamide-treated rats. Testicular weight, seminiferous tubular diameter, and spermatogenesis were all significantly reduced in the undescended testes (UDT) compared to the contralateral and control testes. Moreover, the development of the contralateral testis was inhibited in group I compared to groups II and III. Our observations showed that short-term exposure to flutamide in utero induced significantly reduced fertility and degenerated contralateral scrotal testes in UCO rats compared to mechanically-induced UCO rats by early adulthood. It is suggested that fertility potential and testicular development in unilateral UDT may be partially due to the factors that induce testicular maldescent, especially in cases due to intrauterine hormonal abnormalities. These cases may show inhibited fertility and testicular development even after orchiopexy.

Androgen Antagonists↗
PubMed1991

Ultrastructure of the aging human testis.

The ultrastructure of the progressive testicular involution with advancing age in men is reviewed. There is no definite age at which testicular involution begins, and the onset and severity of testicular lesions are subjected to pronounced individual variations. Hormone studies also indicate great individual variations, and subtle changes in both the testis and the pituitary develop progressively with age. Testicular size, sperm quality, and numbers of all germ cell types, Sertoli cells, and Leydig cells decrease with age. The volume occupied by the seminiferous tubules decreases, whereas that occupied by the testicular interstitium remains constant. The most frequent histological pattern of the aging testis is a mosaic of different seminiferous tubule lesions, varying from tubules with complete, although reduced, spermatogenesis, to completely sclerosed tubules. The tubules with complete spermatogenesis may show numerous morphological abnormalities in the germ cells, including multinucleation. Abnormal germ cells degenerate causing Sertoli cell vacuolation. These vacuoles correspond to dilations of the extracellular spaces resulting from the premature exfoliation of germ cells. Degenerating cells that are phagocytosed by the Sertoli cells give rise to an accumulation of lipid droplets in the Sertoli cell cytoplasm. The loss of germ cells begins with the spermatids, but progressively affects the earlier germ cell types, and tubules with maturation arrest at the level of the spermatocytes or spermatogonia are observed. The Sertoli cells show morphological abnormalities such as dedifferentiation, mitochondrial metaplasia, and multinucleation. Germ cell loss is associated with thickening of the tunica propria. When all seminiferous epithelial cells have disappeared, only an intensely collagenized tunica propria with myoid cells remains (sclerosed tubules). The Leydig cells progressively dedifferentiate with a decrease in the quantity of both smooth endoplasmic reticulum and mitochondria, together with an accumulation of lipid droplets, crystalline inclusions, and residual bodies, and formation of multinucleate cells. The development of tubular involution with age is similar to that observed after experimental ischemia, suggesting that vascular lesions may play an important role in age-related testicular atrophy.

Aging↗
PubMed2005

The expression of plexins during mouse embryogenesis.

Plexins are large transmembrane proteins that are receptors for semaphorins, either alone or in a complex with neuropilin-1 or -2. Nine different mouse plexins have been found: Plexin-A1-4, -B1-3, -C1 and -D1. The expression and function of plexins in non-neuronal tissues has been poorly characterized, although Plexin-A1 has been shown to have a role during lung and cardiac morphogenesis. We have done an extensive non-radioactive in situ hybridisation survey of Plxna1-a4, Plxnb1 -b3 and Plxnc1 in E14 mouse embryo. At E14, Plxnb3 expression could not be detected by in situ hybridisation. All other plexins studied are widely expressed both in neuronal and non-neuronal tissues. We have also followed the expression patterns of plexins during the development of the kidney, tooth and testis. Plxnb1 and Plxnb2 are expressed in the immature glomeruli and mesenchyme of the developing kidney. In the tooth bud, Plxna1 and Plxnb1 are expressed in the oral epithelium, enamel knot and in both the inner and outer enamel epithelium, whereas the expression of Plxnb2 is more restricted to the inner enamel epithelium. In the testis, Plxna1, Plxnb1 and Plxnc1 are expressed in the developing sex chords. This study shows that during development, plexins are expressed in specific and distinct patterns also in non-neuronal tissues.

Animals↗
PubMed2003

Turning on the male--SRY, SOX9 and sex determination in mammals.

The decision of the bi-potential gonad to develop into either a testis or ovary is determined by the presence or absence of the Sex-determining Region gene on the Y chromosome (SRY). Since its discovery, almost 13 years ago, the molecular role that SRY plays in initiating the male sexual development cascade has proven difficult to ascertain. While biochemical studies of clinical mutants and mouse genetic models have helped in our understanding of SRY function, no direct downstream targets of SRY have yet been identified. There are, however, a number of other genes of equal importance in determining sexual phenotype, expressed before and after expression of SRY. Of these, one has proven of central importance to mammals and vertebrates, SOX9. This review describes our current knowledge of SRY and SOX9 structure and function in the light of recent key developments.

Animals↗
PubMed1978

Follitropin receptors in rat testis. Characterization with enzymatically 125I-labeled human follitropin.

The interaction between enzymatically radioiodinated human follitropin and the follitropin receptors in testis homogenate was investigated in immature and adult rats. The 125I-labeled human follitropin exhibited high binding activity with specific binding of up to 17% in the presence of an excess of testis homogenate. Approx. 50% of the bound hormone could be eluted at pH 5, and the receptor purified tracer exhibited a 3.6-fold increase in binding activity when compared with the original tracer preparation. Quantitative analysis of equilibrium binding data was performed with corrections for the measured specific activity and maximum binding activity of the tracer hormone. The equilibrium association constants (Ka) determined 24 degrees C were not significantly different in immature and adult rat testis, and the mean value for Ka was 3.9 . 10(9) M-1. At 37 degrees C, the Ka value obtained using immature rat testis was 1.3 . 10(10) M-1. The association of 125I-labeled human follitropin with immature rat testis homogenate was time and temperature dependent. In the presence of an excess of unlabeled hormone, 30--60% of the preformed hormone . receptor complex was dissociated after 24 h incubation. A specific and sensitive radioligand-receptor assay for follitropin was developed using immature rat testis homogenate. The minimum detectable dose of purified human follitropin was 0.6 ng, and human urinary and pituitary follitropin, ovine follitropin and pregnant mare serum gonadotropin reacted in the assay with equivalent slopes. The potencies of highly purified pregnent mare serum gonadotropin and highly purified human follitropin were similar in the radioligand-receptor assay, consistent with the follitropin bioactivity of the equine gonadotropin.

Animals↗
PubMed1985

Varicocele and puberty--the critical factor?

In some boys varicocele develops before puberty, when the testis is immature and vulnerable. Based on testicular size, evidence suggests that the time of development of a varicocele in relation to puberty may be the critical factor in the subsequent development of infertility. The recognition and treatment of an early-developing varicocele may help to reduce the infertility associated with this condition.

Adolescent↗
PubMed2001

Standard and C-banded meiotic karyotypes of Psylloidea (Sternorrhyncha, Homoptera, Insecta).

Meiotic karyotypes were studied in males of Craspedolepta sonchi (Foerster, 1848), Diaphorina chobauti Puton, 1898, D. lamproptera Burckhardt, 1981, Psylla hartigii Flor, 1861, Cacopsylla palmeni (Loew, 1878), C. hippophaes (Foerster, 1848), C. melanoneura (Foerster, 1868), C. pyricola (Foerster 1848), C. moscovita (Andrianova, 1848), Bactericera salicivora (Reuter, 1876), Trioza abdominalis Flor, 1861, T. lauri = Lauritrioza alacris (Flor, 1861). Karyotypes were 2n = 25 (24 + XO) in all species except B. salicivora with 2n = 26 (24 + neo-XY). Testes consisted of two follicles each in all species but P. hartigii with four-follicular testes in males. The discussion covers the problems of chromosome numbers, sex-determining chromosome systems, B-chromosomes, patterns of C-banding, testis structure, and spermatid development in Psylloidea.

Animals↗
PubMed1977

Carcinoma in situ of the ectopic testis.

A young man with a palpable ectopic testis underwent right testis biopsy and orchiopexy. Since histological findings of the biopsy specimen revealed an unsuspected intratubular carcinoma in situ and evidence of diminished spermatogenic potential, an inguinal orchiectomy was done. This appears to be the first reported case of a tumor of this type developing in an undescended testis.

Adult↗
PubMed1998

Fertility and histological studies of the contralateral testes in two different intra- and extra-abdominal rat models of unilateral cryptorchidism.

OBJECTIVE: To investigate the effect of location of the testis on both testicular development and fertility in unilateral cryptorchidism. MATERIAL AND METHODS: Forty-nine Wistar King A newborn male rats were divided into three groups. In group 1 (15 rats) intra-abdominal unilateral cryptorchidism were created by the intra-abdominal fixation of the testis in the neonatal period. In group 2 (16 rats) extra-abdominal unilateral cryptorchidism was created by extra-abdominal fixation of the gubernaculum in the neonatal period. In group 3, 18 rats underwent a sham operation as controls. At 90 days of age, fertility was then assessed in each rat by housing it with two mature virgin females for 2 weeks. Thereafter, at 115-120 days of age, the rats were killed and their testes removed for histological examination. RESULTS: There was no significant difference in the pregnancy rate between females coupled with rats from any group, but the mean number of offspring was significantly lower in females coupled with rats in group 1 than in group 2. Furthermore, histological examination of both the cryptorchid and contralateral scrotal testes showed more severe changes in the intra-abdominal than the extra-abdominal testes. CONCLUSION: These results suggest that intra-abdominal cryptorchid testes are significantly more impaired than extra-abdominal cryptorchid testes, and that such impairment might be caused by exposure of the testis to a higher temperature. The more severely impaired undescended testes may thus induce the degeneration of the contralateral scrotal testis and thereby cause subfertility in the intra-abdominal unilateral cryptorchid rat model.

Animals↗
PubMed1982

[Cytodiagnosis of prostatic and testicular neoplasms].

Struck by delays in the diagnosis of carcinomas of the prostate and testis, the authors have developed a method for cytological study by puncture of those organs. During a 7 year period, they saw 100 carcinomas of the prostate, 94% of which had already spread beyond the prostate with bone metastases in 48%. During the same period, 18 carcinomas of the testis were seen, with several erroneous differential diagnoses which led to a delay in diagnosis (mean: 12 weeks). The authors use a Franzen-type aspiration needle which makes possible puncture and aspiration of the tumour zone without hospitalisation of the patient. Cytological diagnosis implies the need for considerable experience, bearing in mind that in particular certain excessively deep punctures of the prostate may yield cells from the seminal vesicles which lead to an incorrect diagnosis of carcinoma of the prostate. Such aspiration cytology may be used to differentiate between benign and malignant tumours, as well as providing a more accurate diagnosis in terms of the type of tumour and the degree of differentiation.

Biopsy, Needle↗