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Historical milestones regarding torsion of the scrotal organs.

PURPOSE: The clinical syndrome of the acute scrotum, whereby the spermatic cord or appendix testis becomes twisted, commonly affects young men. Our knowledge of this condition, however, is of relatively recent origin. MATERIALS AND METHODS: We performed an historical survey of torsion of the scrotal organs dating back to 1703. In Bologna in 1703 Morgagni observed the first hydatid on the caput epididymis. He described 10 hydatid cases of the testis and epididymis producing, in his opinion, the fluid of hydroceles. The first illustration of appendix testis dates from Cooper 1841. Later these testicular appendages, or hydatids, were shown to be vestigial remnants of either the müllerian duct or the wolffian structures, depending on location. Actual torsion of the appendix testis was mentioned by Ombrédanne in 1913 but the first case report was published in 1922 by Colt. Appendix testis torsion was first schematically illustrated in 1923 by Mouchet and was characterized by Dix in 1931 in a manner that is still valid today. Interestingly, the great majority of case reports since 1932 have originated from America. In 1810 Hunter described a typical case of testicular torsion, and in 1840 Delasiauve presented the first case of surgically treated testicular torsion. A schematic and original illustration of a contorted undescended testis was published in 1894 by Lauenstein. RESULTS: Testicular torsion was, and still is, a true urological emergency but the historical survival rate of the testis was extremely low. Searching for improvement in clinical diagnosis, physicians have noted helpful specific signs, 1 of which is that the period of ischemia determines loss of the testis. CONCLUSIONS: The historical development of diagnosis of torsion of the appendix testis and spermatic cord highlights the ever present need for careful examination, a high index of suspicion and timely therapy.

Europe↗

The effect of non-union of testis and epididymis and of cryptorchidism on the development of epididymis and ductus deferens in the rat.

16-days old rats were operated with either uni- or bilateral ligation of ductuli efferents and separation of testis and epididymis to the level of the inferior epididymal artery (non-union operation), induction of cryptorchidism or bilateral sham operation. The epididymides were weighed and the epididymides and deferent ducts were examined with light- and electron-microscopy at days 30, 37, 44 and 58. Bilateral non-union operated epididymides and cryptepididymides had a significantly lower weight increase than controls, but the histology and diameter of epididymal tubules were unchanged. This indicates a true growth retardation and reduced length of epididymal tubules of non-union operated and cryptepididymides. For bilateral operations a positive correlation was found between the weight of epididymis and plasma levels of total testosterone as reported earlier. Unilaterally operated epididymides had a weight development significantly below contralateral controls, despite normal plasma levels of testosterone. It is concluded that the reduced-weight of unilaterally operated epididymides is the result of diminished local androgen stimulation from the ipsilateral testis. Non-union of testis and epididymis may have pathogenetic significance in maldescent of testis by a retarded growth of the ductal system.

Animals↗

Cellular interrelationships in the human fetal ovary and testis.

Information on the cellular changes involved in human gonadal maturation has increased considerably in recent years with the introduction of special techniques for coordinating structural and functional analyses. An approach that appears to be particularly promising is the use of freeze-fracture techniques. Utilizing this method, we have demonstrated the formation of specialized intercellular junctions in the developing ovary and testis. Studies in several species have indicated similar findings which relate to the formation of the blood-testis barrier and the coordination of cellular activity involved in steroidogenesis. Further progress in understanding of maturational changes in the developing gonads will depend on continuing correlation of structural and functional changes in specific cell populations.

Cell Differentiation↗

Short-time exposure to vinclozolin in utero induces testicular maldescent associated with a spinal nucleus alteration of the genitofemoral nerve in rats.

BACKGROUND/PURPOSE: Vinclozolin (V), a known antiandrogen, has been used widely to protect fruits, vegetables, and turf from fungus damage. The aim of this study was to clarify the effect of V on both the development of the spinal cord nucleus and testicular descent in rats. METHODS: Pregnant rats were administered 200 mg/kg/d of V from day 16 to 18 of gestation. At 5 days of age, the genitofemoral nerve (GFN) of male pups was identified on the psoas muscle, and diamidinophenyl indole was applied to the proximal cut end of the GFN. Forty-eight hours later, the T11 to L4 level of the spinal cord was removed, and 30-microm frozen serial sections were made. Next, the spinal nuclei labeled in a retrograde fashion by diamidinophenyl indole (DAPI) were examined with a fluorescence microscope. Additional male pups survived until 60 days of age to evaluate the position of the testes. RESULTS: The size of the DAPI-labeled spinal nuclei were smaller in the V-treated rats than in the control rats. The average number of the DAPI-labeled spinal nuclei decreased significantly more in the V-treated rats (176+/-33) than in the controls (247+/- 21; P <.05) during the newborn period. At 60 days of age, 15 of the 26 male rats showed either unilateral or bilateral undescended testes in the V-treated rats. The incidence of cryptorchidism was also significantly higher in the V-treated rats (57.7%) than in the controls (0%; P <.05). CONCLUSIONS: The antiandrogenic effect of the prenatal administration of V inhibited the development of the GFN nucleus in the spinal cord and induced testicular maldescent in rats. These results support the hypothesis that androgens regulate the descent of the testis through GFN development.

Androgen Antagonists↗

[Lack of reductase as cause of andrological disturbance?].

We studied steroid metabolites of 35 men with oligoasthenoteratozoospermia. We found a significant decrease of androsterone (p less than 0,01) in urine. The quotient of aetiocholanolone: androsterone was significantly increased (p less than 0,01). This means that there might be a lack of 5 alpha-reductase function. Patients with E: A higher than 3,0 showed a significant side-difference of testis volume compared with the control group (p less than 0,01). We suppose that lack of 5 alpha-reductase induces dissociation of the development of the testis.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗

The effect of hyperthermia on the induction of cell death in brain, testis, and thymus of the adult and developing rat.

Stressful stimuli can elicit 2 distinct reactive cellular responses, the heat shock (stress) response and the activation of cell death pathways. Most studies on the effects of hyperthermia on the mammalian nervous system have focused on the heat shock response, characterized by the transient induction of Hsps, which play roles in repair and protective mechanisms. This study examines the effect of hyperthermia on the induction of cell death via apoptosis, assayed by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling and active caspase 3 cytochemistry, in the adult rat brain, testis, and thymus. Results show that a fever-like increase in temperature triggered apoptosis in dividing cell populations of testis and thymus, but not in mature, postmitotic cells of the adult cerebellum. These differential apoptotic responses did not correlate with whole-tissue levels of Hsp70 induction. We further investigated whether dividing neural cells were more sensitive to heat-induced apoptosis by examining the external granule cell layer of the cerebellum at postnatal day 7 and the neuroepithelial layers of the neocortex and tectum at embryonic day 17. These proliferative neural regions were highly susceptible to hyperthermia-induced apoptosis, suggesting that actively dividing cell populations are more prone to cell death induced by hyperthermia than fully differentiated postmitotic neural cells.

Age Factors↗

Stem cell pluripotency factor NANOG is expressed in human fetal gonocytes, testicular carcinoma in situ and germ cell tumours.

AIMS: NANOG is a key regulator of embryonic stem cell (ESC) self-renewal and pluripotency. Our recent genome-wide gene expression profiling study of the precursor of testicular germ cell tumours, carcinoma in situ testis (CIS), showed close similarity between ESC and CIS, including high NANOG expression. In the present study we analysed the protein expression of NANOG during normal development of human testis and in a large series of neoplastic/dysgenetic specimens. METHODS AND RESULTS: We detected abundant expression of NANOG in CIS and in CIS-derived testicular tumours with marked differences; seminoma and embryonal carcinoma were strongly positive, differentiated somatic elements of teratoma were negative. We provide evidence for the fetal origin of testicular cancer as we detected strong expression of NANOG in fetal gonocytes up to gestational week 20, with subsequent down-regulation occurring earlier than for OCT-4. We detected no expression at the protein level in normal testis. CONCLUSIONS: NANOG is a new marker for testicular CIS and germ cell tumours and the high level of NANOG along with OCT-4 are determinants of the stem cell-like pluripotency of the preinvasive CIS cell. Timing of NANOG down-regulation in fetal gonocytes suggests that NANOG may act as a regulatory factor up-stream to OCT-4.

Adolescent↗

Estrogen-induced gonadal sex reversal in the tammar wallaby.

Estrogens have a feminizing effect on gonadal differentiation in fish, amphibians, reptiles, and birds. However, the role of estrogen during gonadal differentiation in mammals is less clear. We investigated the effect of estrogen on gonadal differentiation of male tammar wallabies. Male pouch young were treated orally with estradiol benzoate or oil from the day of birth, before seminiferous cords develop, to Day 25 postpartum and were killed at Day 50 postpartum. In all estrogen-treated neonates, a decrease in gonadal volume, volume of the seminiferous cords, thickness of the tunica albuginea, and number of germ cells was found. The stage of treatment affected the magnitude of the response. Two of three male young born prematurely after 25 days of gestation and treated subsequently with estradiol had ovary-like gonads, with well-developed cortical and medullary regions and primordial follicle formation. Furthermore, at Day 50 postpartum, many (21%) of the germ cells in these sex-reversed ovaries were in the leptotene and zygotene stages of meiosis, similar to female germ cells at the same stage of development. In the other males born on Day 26 of gestation or later, estradiol treatment from the day of birth caused development of dysgenetic testes, with abnormal Sertoli cells, atrophy of the seminiferous tubules and tunica albuginea, and absence of meiotic germ cells. In this marsupial, therefore, estradiol can induce either partial or complete transformation of the male gonads into an ovary with meiotic germ cells. These results confirm that estrogen can inhibit early testicular development, and that testis determination occurs during a narrow window of time.

Animals↗

Role of gain of 12p in germ cell tumour development.

Within the human testis, three entities of germ cell tumours are distinguished: the teratomas and yolk sac tumors of newborn and infants, the seminomas and nonseminomas of adolescents and young adults, referred to as testicular germ cell tumours (TGCT), and the spermatocytic seminomas. Characteristic chromosomal anomalies have been reported for each group, supporting their distinct pathogenesis. TGCT are the most common cancer in young adult men. The initiating pathogenetic event of these tumours occurs during embryonal development, affecting a primordial germ cell or gonocyte. Despite this intra-uterine initiation, the tumour will only be clinically manifest after puberty, with carcinoma in situ (IS) as the precursor. All invasive TGCT, both seminomas and nonseminomas, as well as CIS cells are aneuploid. The only consistent (structural) chromosomal abnormalities in invasive TGCT are gains of the short arm of chromosome 12, mostly due to isochromosome (i(12p)) formation. This suggests that an increase in copy number of a gene(s) on 12p is associated with the development of a clinically manifest TGCT. Despite the numerous (positional) candidate gene approaches that have been undertaken thus far, identification of a causative gene(s) has been hampered by the fact that most 12p gains involve rather large genomic intervals, containing unmanageable numbers of candidate genes. Several years ago, we initiated a search for 12p candidate genes using TGCT with a restricted 12p-amplification, cytogenetically identified as 12p11.2-p12.1. This approach is mainly based on identification of candidate genes mapped within the shortest region of overlap of amplification (SROA). In this review, data will be presented, which support the model that gain of 12p-sequences is associated with suppression of apoptosis and Sertoli cell-independence of CIS cells. So far, DAD-R is one of the most likely candidate genes involved in this process, possibly via N-glycosylation. Preliminary results on high through-put DNA- and cDNA array analyses of 12p-sequences will be presented.

Adolescent↗

Development of agranular reticulum in Sertoli cells of the testis of the dogfish Squalus acanthias during spermatogenesis.

Biochemical analyses of Squalus testis indicates that key enzymes involved with androgen production increase progressively from immature regions containing spermatogonia to mature regions in the late spermatid stage of maturation (Canick et al., 1983). In an effort to identify cells possessing the cytological characteristics of steroid production and to determine the structural correlates of the observed functional changes, we have carried out an electron microscopic study of Squalus testis. This report demonstrates that Sertoli cells contain a well-developed agranular reticulum, mitochondria with tubulovesicular cristae, and numerous lipid droplets. Moreover, as germ cells mature, there is an increase in abundance of agranular reticulum in the adjacent Sertoli cells. By the time of spermatid elongation, this has reached dramatic proportions and fills the Sertoli cell as a mass of tubules. These results lead us to conclude that the Sertoli cell is responsible for secretion of the increasing amounts of androgen during the spermatogenetic cycle in Squalus.

Animals↗

Cell junction dynamics in the testis: Sertoli-germ cell interactions and male contraceptive development.

Spermatogenesis is an intriguing but complicated biological process. However, many studies since the 1960s have focused either on the hormonal events of the hypothalamus-pituitary-testicular axis or morphological events that take place in the seminiferous epithelium. Recent advances in biochemistry, cell biology, and molecular biology have shifted attention to understanding some of the key events that regulate spermatogenesis, such as germ cell apoptosis, cell cycle regulation, Sertoli-germ cell communication, and junction dynamics. In this review, we discuss the physiology and biology of junction dynamics in the testis, in particular how these events affect interactions of Sertoli and germ cells in the seminiferous epithelium behind the blood-testis barrier. We also discuss how these events regulate the opening and closing of the blood-testis barrier to permit the timely passage of preleptotene and leptotene spermatocytes across the blood-testis barrier. This is physiologically important since developing germ cells must translocate across the blood-testis barrier as well as traverse the seminiferous epithelium during their development. We also discuss several available in vitro and in vivo models that can be used to study Sertoli-germ cell anchoring junctions and Sertoli-Sertoli tight junctions. An in-depth survey in this subject has also identified several potential targets to be tackled to perturb spermatogenesis, which will likely lead to the development of novel male contraceptives.

Animals↗

[Leydigioma--rare testicular tumor diagnosed in an adult male with undescended intraabdominal testis].

Leydig cell tumours deriving from the gonadal stroma represent one per cent of all testicular tumours. They may occur at any age. Ten per cent of cases are malignant. There is no evidence that they are prone to develop in undescended testis. We report the rare case of leydigioma in 71 year old man with unilateral cryptorchidism. Only a few cases have been reported as arising from undescended testis.

Aged↗

Ultrastructure of developing germ cells in the fetal human testis.

Electron microscopic studies of the testis were performed on 12 human embryos and fetuses between 9 and 30 weeks post conceptionem. According to their ultrastructural features, the fetal germ cells could be divided into the following three stages of differentiation: 1) gonocytes, 2) intermediate cells, and 3) fetal spermatogonia. Sertoli cells were present among the germ cells in all the testes studied. The gonocytes showed the highest nucleo-cytoplasmic ratio. Their round nucleus contained a centrally located, prominent nucleolus. The cytoplasm displayed a well developed Golgi apparatus, lipid droplets and parallel arrays of short cisternae of the rough surfaced endoplasmic reticulum (rER). Microfilaments were numerous, particularly just beneath the cell membrane. The intermediate cells were found to extend several cytoplasmic processes and to contain a moderate number of long, branched and/or widened rER cisterna which were frequently connected to the perinuclear cisterna. Intermediate cells were often connected to one another by intercellular cytoplasmic bridges. The fetal spermatogonia also displayed cytoplasmic bridges. These cells showed the lowest nucleo-cytoplasmic ratio and more condensed nuclear chromatin. The mitochondria were situated close to the nucleus. Many of them were connected by a cementing substance. Lipid droplets and rER cisternae were rare in these cells. Infoldings of the inner nuclear membrane were often present in the gonocytes and in the intermediate cells, but were rarely observed in the fetal spermatogonia. Glycogen particles, polyribosomes, and chromatoid bodies ("nuage") were present in all the three germ cell types. With the maturation of the fetus, the number of gonocytes was found to decrease, whereas the number of fetal spermatogonia increased. The Sertoli cells also changed their ultrastructure, showing an increase in the number of rER cisternae, as well as of microfilaments, lipid droplets, and secondary lysosomes.

Age Factors↗

Annual cycles of steroid hormone production, gonad development, and reproductive behavior in the Atlantic stingray.

The mating season of the Atlantic stingray (Dasyatis sabina), which begins in August and continues through April, is the longest documented for any elasmobranch fish. Despite this protracted mating period, female stingrays ovulate synchronously at the end of the mating season and there is no evidence for sperm storage by females. Thus, the proximate causal factors and ultimate function of this extended preovulatory mating are unknown. Annual cycles of the gonadal steroids testosterone (T), dihydrotestosterone (DHT), 17beta-estradiol (E2), and progesterone (P4) were measured for 26 months in a wild estuarine population of Atlantic stingrays to test for associations with their reproductive biology, gametogenesis, and sexual behavior. Serum androgen levels in males showed four phases within an annual cycle: (1) androgen suppression between reproductive seasons (April-July), (2) primary androgen increase during the onset of spermatocyte development (August-October), (3) androgen decrease following maximum testis growth and spermatocyte development (November-December), and (4) secondary androgen increase during the peak of sperm maturation (January-March). Increases in male E2 and P4 were correlated with spermatocyte/spermatocyst formation, maximum testis weight, and the primary (but not secondary) androgen surge. We propose that the production of male androgens across the full seven-month preovulatory mating period promotes their aggressive reproductive behavior and drives the protracted mating season of this species. In females, serum T and DHT showed relatively brief increases near ovulation, whereas E2 and P4 showed brief increases near both ovulation and parturition. The increase in female androgens near ovulation may increase female aggression when they are impregnable by courting males and enhance their choice of mates. This estuary sample population shows higher absolute steroid levels and distinct differences in temporal cycles compared to another Florida fresh water lake population, but the cause and significance of these differences are unknown. Experiments are needed to confirm that the aggressive and protracted mating behavior is the result of prolonged male androgen production and to determine whether the sustained preovulatory mating serves some function related to female reproduction.

Animals↗

twine, a cdc25 homolog that functions in the male and female germline of Drosophila.

twine is the second homolog of the fission yeast gene cdc25 to be found in Drosophila. Both string and twine cDNAs can rescue a temperature-sensitive cdc25 mutation in fission yeast, but not a deletion. We detect the expression of string but not twine transcripts in the proliferating cells of newly cellularized embryos, in third instar larval brains, and in imaginal discs. Both genes are abundantly expressed in nurse cells during oogenesis, the maternal transcripts persisting throughout the syncytial stage of embryonic development. In the testis, twine transcripts are seen in the growing stage of premeiotic cysts. Analysis of a twine mutant suggests a requirement for the gene during oogenesis, during syncytial embryonic development, and for male meiosis. Meiosis does not occur in homozygous twine males, which produce cysts containing 16 rather than 64 spermatids.

Amino Acid Sequence↗

In vivo gene transfer by electroporation allows expression of a fluorescent transgene in hamster testis and epididymal sperm and has no adverse effects upon testicular integrity or sperm quality.

The study of gene function in testis and sperm has been greatly assisted by transgenic mouse models. Recently, an alternative way of expressing transgenes in mouse testis has been developed that uses electroporation to introduce transgenes into the male germ cells. This approach has been successfully used to transiently express reporter genes driven by constitutive and testis-specific promoters. It has been proposed as an alternative method for studying gene function in testis and sperm, and as a novel way to create transgenic animals. However, the low levels and transient nature of transgene expression that can be achieved using this technique have raised concerns about its practical usefulness. It has also not been demonstrated in mammals other than mice. In this study, we show for the first time that in vivo gene transfer using electroporation can be used to express a fluorescent transgene in the testis of a mammal other than mice, the Syrian golden hamster. Significantly, for the first time we demonstrate expression of a transgene in epididymal sperm using this approach. We show that expression of the transgene can be detected in sperm for as long as 60 days following gene transfer. Finally, we provide the first systematic demonstration that this technique does not lead to any significant long-term adverse effects on testicular integrity and sperm quality. This technique therefore offers a novel way to study gene function during fertilization in hamsters and may also have potential as a way of creating transgenic versions of this important model species.

Animals↗

Testis epidermal growth factor and spermatogenesis.

Epidermal growth factor (EGF) is a cytokine that promotes cell proliferation, regulates tissue differentiation, and modulates organogenesis. Although a rich source of EGF is the submaxillary gland, many tissues produce this cytokine, including the testis. Leydig cells are the principal source of EGF in the testis. On attainment of sexual maturation the germ cells, primarily spermatocytes and round spermatids, form EGF with the onset of spermatogenesis. EGF appears to be involved in the development of the testis and in spermatogenesis. The expression of the EGF gene in rat testis was determined by the application of the RT-PCR method and testis RNA as substrate. The results suggest that EGF produced by Leydig cells and germ cells may modulate spermatogenesis as an autocrine and/or paracrine factor.

Animals↗

Effect of 17beta-estradiol, o,p'-DDT, octylphenol and p,p'-DDE on gonadal development and liver and kidney pathology in juvenile male summer flounder (Paralichthys dentatus).

The intent of this study was to compare histopathologically the effect of 17beta-estradiol (E(2)), o,p'-DDT, octylphenol and p,p'-DDE on gonadal development and liver and kidney condition in sexually immature (juvenile) summer flounder (Paralichthys dentatus). The dorsal sinus of 2-year-old juvenile male summer flounder was injected with the appropriate amount of chemical incorporated in coconut oil. A second identical injection was administered 2 weeks later. Fish were sampled at 4, 6 and 8 weeks after the initial injection and observed histopathologically. In control fish, spermatogenesis was predominantly in mid to late maturation. In fish treated with 1.0 and 10.0 mg/kg E(2) spermatogenesis regressed to primary spermatogonia or an immature functional state. Testicular atrophy and spermatogonial proliferation was also observed. An eosin-positive, hyaline material was found in the gonad, liver and kidney. This eosinophilic material also stained positive with Periodic Acid Schiff (PAS) stain. Treatment of 30 or 60 mg/kg o,p'-DDT elicited altered gonadal development similar to that observed with E(2) treated fish. Octylphenol treatment of 100 mg/kg resulted in reduced testicular size, ducts full of sperm, numerous spermatogonia and PAS positive material in the testis with no developing sperm cysts. No effect on liver or gonad tissues was observed with p,p'-DDE at the concentrations tested. All chemicals tested, with exception of p,p'-DDE, altered gonadal development, whereas only E(2) caused histopathological changes in the liver and kidney. Estrogenic activity induced the liver to produce a vitellogenin (VtG)-like substance and inhibited testicular maturation. As a result, both the lack of target cells for VtG and a continuous supply of VtG from the liver allowed the hyaline material to accumulate in the liver, testis and kidney causing histopathological changes.

Animals↗