Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “testis development”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,261 records · Page 70Linked to original sources

Torsion of the testis and allied conditions.

In 15 years at Bristol there have been 293 cases of torsion of the testis, 55 cases of torsion of a testicular appendage and 5 cases of testicular ischaemia due to other causes. The risk of a male developing torsion of the testis or its appendix by the age of 25 is about 1 in 160. Both conditions occurred primarily in adolescents, but among prepubertal boys torsion of an appendage was as common as torsion of a normally descended testis. There was a slight left-sided preponderance in testicular torsion, more marked in torsion of the appendages; the incidence of bilateral torsion was 2-0 and 1-8 per cent respectively. The clinical features and differential diagnosis of the two conditions are compared. Torsion of a testicular appendage is the most commonly misdiagnosed scrotal lesion, the preoperative diagnosis being correct in only 11 per cent of cases compared with 90 per cent for torsion of the testis. Twenty-one cases of recurrent torsion underwent prophylactic bilateral orchidopexy. There were 20 cases of torsion of undescended testes, with a salvage rate of only 20 per cent. The overall testicular survival rate was 55-3 per cent. Viability depends upon the possibility of spontaneous reduction, the preoperative delay after the onset of symptoms, the degree of torsion of the cord and the length of follow-up in doubtful cases. Urgent scrotal exploration is advised in every case of acute testicular pain unless there is overwhelming evidence of epididymoorchitis. Exploration of the opposite side is mandatory in torsion of the testis and advisable in torsion of an appendage.

Adolescent↗

Effects of nutrition and environmental factors on the fetal programming of the reproductive axis.

Research from a wide range of scientific disciplines has shown that the reproductive performance of animals in adult life is determined, in part, by a variety of extraneous influences acting at different stages of development from before conception until after birth. These effects are probably mediated through changes in the hypothalamic-pituitary and gonadal axes but the physiological system that is affected depends on the stage of development at which the influence is applied. The physiological mechanisms through which environmental influences are transmitted to the target organs are, in many cases, complex and poorly understood. Gonadotrophins seem to play a pivotal role in the development of the fetal testis, although effects of environmental influences on GnRH secretion have yet to be demonstrated. Other studies have shown that, at earlier stages of fetal development, the normal ontogeny of gonadal development and function can be disrupted by undernutrition or the influence of endocrine-disrupting compounds. Specifically, in female fetuses, the onset of meiosis is delayed, whereas, in male fetuses, testosterone synthesis is increased as a result of enhanced testicular steroidogenic enzyme activity. Although reproductive performance is clearly influenced by prenatal factors, much further work is required to identify the relationships between developmental abnormalities and adult reproductive function. Work is also required to elucidate further the critical windows in development and the mechanisms by which environmental factors affect the reproductive organs of developing offspring.

Animals↗

Involvement of insulin-like factor 3 (Insl3) in diethylstilbestrol-induced cryptorchidism.

Recently, it has been shown that targeted inactivation of the Insl3 gene in male mice results in cryptorchidism. The Insl3 gene encodes insulin-like factor 3 (Insl3), which is expressed in fetal Leydig cells. The testicular factor Insl3 appears to play an important role in the transabdominal phase of testis descent, which involves development of the gubernaculum. Other studies have demonstrated that in utero exposure to diethylstilbestrol (DES), a synthetic estrogen, can lead to cryptorchidism both in humans and in animal models. The present study was undertaken to investigate whether prenatal DES-exposure might interfere with testicular Insl3 mRNA expression. Furthermore, the effect of DES on steroidogenic factor 1 (SF-1) mRNA expression level was determined, since it has been shown that SF-1 plays an essential role in transcriptional activation of the Insl3 gene promoter. Timed pregnant mice were treated with DES (100 microg/kg body weight) or vehicle alone on days E9 (gestational day 9) through E17. Control and DES-exposed mouse fetuses were collected at E16, E17 and E18, when transabdominal testis descent is taking place. Lack of gubernaculum development in DES-exposed animals was confirmed by histological analyses at E17. Expression of Insl3 and SF-1 mRNAs was studied in testes of control and DES-exposed fetuses at E16 and E18 by RNase protection assay. Prenatal DES-exposure resulted in a three-fold decrease in Insl3 mRNA expression level (P<0.005), at both E16 and E18. In contrast, DES treatment had no effect on the expression of SF-1 mRNA. These results support our hypothesis that DES may interfere with gubernaculum development by altering Insl3 mRNA expression, providing a possible mechanism by which DES may cause cryptorchidism.

Animals↗

Neuropeptide Y-containing nerves in rat gonads: sex difference and development.

The objectives of the present study were 1) to evaluate for a sex difference in innervation of adult rat gonads by neuropeptide Y-immunoreactive (NPY-I) nerves and 2) to examine the development of innervation of rat gonads by NPY-I nerves during the fetal and neonatal periods. With fluorescence immunocytochemistry, NPY-I nerves were profuse in adult ovarian tissues. Ovarian blood vessels were particularly well innervated by NPY-I nerves, and nerves were also detected in interstitial gland tissues. No nerves were found within the testis, and NPY-I nerves were only rarely located within the tunica albuginea. During fetal life, ovaries were devoid of NPY-I nerves; however, nerves were visualized within the connective tissue immediately peripheral to the ovary on fetal Day 22. As early as postnatal Day 2, NPY-I nerves were observed in connective tissue septa of the developing ovary. By postnatal Day 12, NPY-I nerves surrounded developing follicles and blood vessels of the ovarian cortex. In the developing testis after postnatal Day 5, NPY-I nerves were limited to the tunica albuginea and surrounding large subcapsular blood vessels. Structures within the testis lacked innervation by NPY-I nerves. These anatomical studies suggest that NPY-I nerves are absent in the gonads during fetal life and grow into the ovary and not the testis during the perinatal period and that NPY-I nerves may play a role in the functioning of the rat ovary, but may not be important in control of testicular function.

Animals↗

Foetal genital development in Hyrax capensis, a species with primary testicondia: proposal for the evolution of Hunter's gubernaculum.

BACKGROUND: Control of testicular descent is poorly understood. There are a number of mammalian species in which testis descent does not occur, and the phenomenon is called testicondia. Analysis of foetal development of such species could contribute to a better understanding of the key events in anatomical development underlying testis descent. Specific attention is to be given to the development of the so-called gubernaculum of Hunter: a structure of complex architecture and composition, which extends from the caudal pole of the mesonephric remnants into the inguinal abdominal wall and which is present in most mammals but not in submammalian vertebrates. METHODS: Serially sectioned male and female foetuses of Hyrax capensis, a species in which testes remain close to the caudal pole of the kidneys throughout life, were analysed for architecture of the developing genital apparatus and the immediately surrounding structures. The results of this analysis were compared with those from a similar analysis of reptiles, of monotremata without testis descent, and of mammals with testis descent. RESULTS: Reptiles and Monotremata showed no gubernacular structures. Mammals with testis descent showed gubernacular growth and differentiation which varied between the sexes and with the stage of foetal development. Hyrax capensis foetuses showed the development of only one component of the gubernaculum: the gubernacular cord as a part of the mesonephric mesentery and extending between the caudal pole of the mesonephros (or mesonephric remnants in older foetuses) and the lateral bladder ligament. No part developed in the inguinal abdominal wall components, which are the primordia of the cremaster sacs in species with testis descent. CONCLUSION: Hyrax capensis shows only partial development of the gubernacular structures, and, specifically, the primordia of the cremaster sacs remain absent. Thus, this species lacks a key anatomical condition for testis descent. Gubernacular architecture in Hyrax capensis seems of a degree intermediate between egg laying monotremata mammals and mammals with testis descent. A model is proposed within which to understand the development of the gubernacular components within the mammalian class.

Animals↗

[Effect of anabolic hormones on the testis of calves: a morphopathologic and morphometric study].

The present study was undertaken to determine the morphological changes in calf testicular parenchyma following implantation of anabolics. Oestradiol and trenbolone acetate were observed to delay seminiferous tubule development of the calf testis resulting in a derangement of supporting and germinal cell maturation. We also observed an edematous process that primarily involved the interstitium and subsequently involved the interior of the seminiferous epithelium, causing a chain of subsequent changes. Changes in the germinal epithelium showed profound derangement throughout spermatogenesis and was particularly more marked and manifest during spermiogenesis.

Anabolic Agents↗

Laparoscopic diagnosis and treatment of nonpalpable testis.

OBJECTIVE: Laparoscopy has become one of the important diagnostic modalities of nonpalpable testis and has been developed and applied in the treatment of this disease. In the present study, we investigated the usefulness of laparoscopy in the diagnosis and treatment of nonpalpable testis. METHODS: Laparoscopy was carried out under general anesthesia on 21 patients (23 testes) from October 1991 to October 1999. If the internal spermatic vessels and vas deferens made their way into the internal inguinal ring, the inguinal canal was dissected with an incision in the inguinal region to look for the testis. Patients with intra-abdominal testis underwent laparoscopic orchiopexy or orchiectomy. If the internal spermatic vessels terminated with a blind end intraperitoneally, making it impossible to identify the testis, the case was judged to be vanishing testis and the operation was finalized without any further examination. RESULTS: In eight of 23 testes (35%), the internal spermatic vessels and vas deferens made their way into the internal inguinal ring. The inguinal region was examined in all the eight testes. Orchiopexy was carried out on two testes and orchiectomy was carried out on six testes. An intra-abdominal testis was detected in eight of 23 testes (35%). Laparoscopic orchiopexy was carried out on seven testes. One-stage orchiopexy was carried out on two of the seven testes and two-stage Fowler-Stephens orchiopexy was carried out on five of the seven testes. Orchiectomy was carried out on the remaining testis. Blocking or lack of the internal spermatic vessels and vas deferens was seen in seven of the 23 testes (30%) and this condition was diagnosed as vanishing testis. CONCLUSION: Laparoscopy for nonpalpable testis is considered to be the most effective technique for diagnosing the presence or absence of the testis and the location of the testis.

Adolescent↗

[Influence of a calcium overload on the genital system of the male rat].

Treatment of "Sprague Dawley" immature rats with D3 vitamin subchronic doses during 25 days induces a sexual organs calcification, a delayed body development in general, and specially testis and seminal vesicles growth. The effect of this treatment on the development and secretions of the sex accessory organs is measured by the determination of fructose rate in the seminal liquid.

Animals↗

Localization and quantitative expression of mRNAs encoding the testis-specific histone TH2B, the phosphoprotein p19, the transition proteins 1 and 2 during pubertal development and throughout the spermatogenic cycle of the rat.

Expression of the testis-specific histone TH2B, the phosphoprotein p19, and the transition proteins TP1 and TP2, was localized in the rat testis and quantified, using in situ hybridization of their mRNAs with radiolabeled probes and image analysis. In a first study, expression was assessed during testicular development between day 2 and day 65 postpartum. TH2B mRNAs appeared first in preleptotene spermatocytes (PL) on day 12 and in pachytene spermatocytes (PS) on day 18; p19 mRNAs were present in PS from day 18 onward, and TP1 and TP2 mRNAs were detected in round spermatids (RS) from day 32 onward. In the second trial, the expression of these four genes was studied throughout the cycle of spermatogenic epithelium in mature animals. TH2B mRNAs were localized in B spermatogonia at stage V, and in PL at stages VII and VIII but no longer in leptotene and zygotene spermatocytes. Thereafter, TH2B mRNAs were observed in PS from stages III-IV to XIII. The steady-state mRNA level per cell was high in PS with a maximum at stages IX-X. p19 mRNAs were present in PS from stages III-IV onward and in RS up to stages 1-2 of spermiogenesis. The maximum mRNA level per cell was observed in PS between stages VII and XIII. The presence of TP1 mRNAs was restricted to spermatids from steps 6 to 15-16 of spermiogenesis while TP2 mRNAs were detected in spermatids only between step 7 and step 13. The highest steady-state amounts of mRNAs were observed between step 7 and step 14 for TP1 and between step 10 and step 12 for TP2.

Animals↗

Differential expression of WNT4 in testicular and ovarian development in a marsupial.

BACKGROUND: WNT4 is a key regulator of gonadal differentiation in humans and mice, playing a pivotal role in early embryogenesis. Using a marsupial, the tammar wallaby, in which most gonadal differentiation occurs after birth whilst the young is in the pouch, we show by quantitative PCR during early testicular and ovarian development that WNT4 is differentially expressed in gonads. RESULTS: Before birth, WNT4 mRNA expression was similar in indifferent gonads of both sexes. After birth, in females WNT4 mRNA dramatically increased during ovarian differentiation, reaching a peak by day 9-13 post partum (pp) when the ovarian cortex and medulla are first distinguishable. WNT4 protein was localised in the ovarian cortex and at the medullary boundary. WNT4 mRNA then steadily decreased to day 49, by which time all the female germ cells have entered meiotic arrest. In males, WNT4 mRNA was down-regulated in testes immediately after birth, coincident with the time that seminiferous cords normally form, and rose gradually after day 8. By day 49, when testicular androgen production normally declines, WNT4 protein was restricted to the Leydig cells. CONCLUSION: This is the first localisation of WNT4 protein in developing gonads and is consistent with a role for WNT4 in steroidogenesis. Our data provide strong support for the suggestion that WNT4 not only functions as an anti-testis gene during early development, but is also necessary for later ovarian and testicular function.

Amino Acid Sequence↗

Pictorial review: ultrasound appearances of the rete testis.

The rete testis is formed in the fifth week of intra-uterine life. The epithelium along the medial side of the mesonephric ridge thickens to form a genital ridge; cellular gonadal cords at the periphery of the ridge unite with a tubular network from the mesonephric mesenchyme forming the testicular rete. On ultrasound, a range of normal appearances of the rete testis is recognised from ill-defined areas of decreased reflectivity to a coarse tubular appearance (often with finger like projections). In the present review the embryological development of the rete testis is briefly outlined. In addition, the important anatomical variations, pertinent to ultrasound imaging, will be presented.

Humans↗

Comparison of the high-mobility-group chromosomal proteins in rainbow-trout (Salmo gairdnerii) liver and testis.

Chromatography and characterization of the proteins extracted by 5% (w/v) HClO4 from rainbow-trout (Salmo gairdnerii) liver and testis show that the two tissues present a characteristically different spectrum of high-mobility-group (HMG) proteins. A variant subfraction of HMG C is found in liver, but is not detectable in testis, where even the main fraction of HMG C is present in only very low quantity. A protein, F, which appears to be related to protein H6 has similarly been isolated only from liver and not from testis. Quantification of the HMG proteins in total 5%-HClO4 extracts of trout liver and testis nuclei shows that, in relation to DNA, levels of HMG T1 and T2, and D are more than 2-fold, and C, 20-fold higher in liver than in testis. However, these differences do not result merely from the sequential withdrawal of HMG proteins at the same time that histones are replaced by protamines in the developing spermatid, since in testis, at some stages of maturation, levels of H6 are almost 2-fold higher than in liver. The implications of these findings for the function of HMG proteins are discussed.

Amino Acids↗

Characterization of rat100, a 300-kilodalton ubiquitin-protein ligase induced in germ cells of the rat testis and similar to the Drosophila hyperplastic discs gene.

Conjugation of ubiquitin to proteins is activated during spermatogenesis. Ubiquitination is mediated by ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzymes (UBCs or E2s), and ubiquitin protein ligases (E3s). Since we previously showed that the activated ubiquitination is UBC4 dependent, we characterized Rat100, a UBC4-dependent E3 expressed in the testis. Analysis of expressed sequence tag sequences and immunoblotting showed that Rat100 is actually a 300-kDa protein expressed mainly in the brain and testis and is similar to the human E3 identified by differential display (EDD) protein and the Drosophila hyperplastic discs gene, mutants of which cause a defect in spermatogenesis. Rat100 is induced during postnatal development of the rat testis, peaking at d 25. It is localized only in germ cells and is highly expressed in spermatocytes, moderately in round and slightly in elongating spermatids. In contrast to UBC4 whose removal from a testis extract abrogates much of the conjugation activity, immmunodepletion of Rat100 from the extracts had little effect. Rat100 therefore has a limited subset of substrates, some of which appear associated with the E3 as the immunoprecipitate containing Rat100 supported incorporation of (125)I-ubiquitin into high molecular weight proteins. Thus, Rat100 is the homolog of human EDD and likely of Drosophila hyperplastic discs. This homology, together with our results, suggests that induction of this E3 results in ubiquitination of specific substrates, some of which are important in male germ cell development.

Aging↗

Immunological effects of antitestis antisera on the development of mouse fetuses.

Antimouse testis antisera (AMTAS) were prepared in rabbits by the injection of testis extracts of the adult mice. Administration of 35.6 mg of AMTAS into pregnant mice on day 12.5 of gestation resulted in 27.3% fetal malformations, while administration of 17.8 mg of the same antisera induced 6.0% malformations. Malformations such as limb anomalies, cleft palate, omphalocele, and spina bifida were often accompanied by hemorrhagic lesions. No malformations associated with hemorrhage were found in the control group in spite of the occurrence of hematomas. The immunofluorescent analysis revealed the localization of antitestis antibody (ATAb) in the basement membrane of the testis, in the spermatozoa, the mesometrial vessels, trophectroderm, and the Reichert's membrane. In contrast, there was no localization of IgG when normal rabbit sera were used. The results suggest that the antibody against the basement membrane or against the spermatozoa may be responsible for the occurrence of congenital malformations in the pregnant mice injected with rabbit AMTAS.

Abnormalities, Drug-Induced↗

Early orchiopexy and testis tumors.

A testicular tumor developed in a twenty-year-old man who had undergone orchiopexy at age six. The case illustrates that early orchiopexy affords no protection against subsequent malignant degeneration. The importance of an inguinal approach and a high orchiectomy are stressed.

Adult↗

[Testicular embryonal carcinoma with contralateral synchronous intratubular germ cell neoplasia: analysis of a case].

We report the case of a 20-year old male with a right testicular tumor. Bilateral orchidectomy was practised considering the synchronous clinical, ultrasonographical and histological (intraoperative biopsy) findings of the left testis. The definitive pathological report showed a right embryonal carcinoma with wide intratubular germ cell neoplasia (IGCN) of the contralateral testis. IGCN (formerly carcinoma in situ) is present in about 5% of cases in the contralateral gonad of those patients with a testicular neoplasm. More than 50% will develop cancer in that testis. Clinical and physical examination findings are usually unspecific. The diagnosis of IGCN is based on biopsy, although ultrasonography could give some data too, as some authors report. We analyze the therapy options for IGCN: (orchidectomy, chemotherapy, radiotherapy, or "wait and see"). In our case, the first one was made. Chemotherapy was used due to existence of retroperitoneal lymph node metastases, with an excellent follow-up afterwards.

Carcinoma, Embryonal↗

Does proximal genitofemoral nerve division induce testicular maldescent or ascent in the rat?

OBJECTIVE: To investigate whether the division of the proximal genitofemoral nerve (GFN) in neonatal rats induces testicular undescent or ascent in adulthood. MATERIALS AND METHODS: Neonatal Wistar King A rats underwent a unilateral proximal GFN transection on either the right or left side. At the age of 30 days, testicular descent was examined in all rats and the position of the testis recorded. The animals were allowed to develop further and the position of the testis re-examined at the age of 90-180 days, when the testes were removed and weighed. Sham-operated rats were used as controls. RESULTS: At the age of 30 days, four of the 46 (9%) operated rats showed a unilateral undescended testis on the operated side. At the age of 90-180 days, 43 rats were re-examined (three rats died before re-examination); 34 (79%) of these rats showed undescended testes on the operated side. The occurrence of cryptorchidism was significantly higher in the 90-180-day-old mature rats than in 30-day-old prepubertal rats (P<0.01). The mean (sd) weight of the undescended testes, at 2.36 (0.21) mg/g body weight, was significantly less than that of the contralateral scrotal testes, at 3.83 (0.23) mg/g; P<0.01) and of the control testes at the age of 90-180 days. In the sham-operated rats, all testes were located at the bottom of the scrotum at 30 days of age and no rats showed any testicular ascent thereafter. CONCLUSIONS: The proximal division of the GFN in neonatal rats not only causes inguinoscrotal testicular maldescent but may also induce testicular ascent in adulthood. Testicular ascent may thus be caused by some intrauterine disorders of the GFN in patients with ascending testis.

Animals↗

Peripheral expression and biological activities of GDNF, a new neurotrophic factor for avian and mammalian peripheral neurons.

Glial cell line-derived neurotrophic factor (GDNF) is a neurotrophic polypeptide, distantly related to transforming growth factor-beta (TGF-beta), originally isolated by virtue of its ability to induce dopamine uptake and cell survival in cultures of embryonic ventral midbrain dopaminergic neurons, and more recently shown to be a potent neurotrophic factor for motorneurons. The biological activities and distribution of this molecule outside the central nervous system are presently unknown. We report here on the mRNA expression, biological activities and initial receptor binding characterization of GDNF and a shorter spliced variant termed GDNF beta in different organs and peripheral neurons of the developing rat. Both GDNF mRNA forms were found to be most highly expressed in developing skin, whisker pad, kidney, stomach and testis. Lower expression was also detected in developing skeletal muscle, ovary, lung, and adrenal gland. Developing spinal cord, superior cervical ganglion (SCG) and dorsal root ganglion (DRG) also expressed low levels of GDNF mRNA. Two days after nerve transection, GDNF mRNA levels increased dramatically in the sciatic nerve. Overall, GDNF mRNA expression was significantly higher in peripheral organs than in neuronal tissues. Expression of either GDNF mRNA isoform in insect cells resulted in the production of indistinguishable mature GDNF polypeptides. Purified recombinant GDNF promoted neurite outgrowth and survival of embryonic chick sympathetic neurons. GDNF produced robust bundle-like, fasciculated outgrowth from chick sympathetic ganglion explants. Although GDNF displayed only low activity on survival of newborn rat SCG neurons, this protein was found to increase the expression of vasoactive intestinal peptide and preprotachykinin-A mRNAs in cultured SCG neurons. GDNF also promoted survival of about half of the neurons in embryonic chick nodose ganglion and a small subpopulation of embryonic sensory neurons in chick dorsal root and rat trigeminal ganglia. Embryonic chick sympathetic neurons expressed receptors for GDNF with Kd 1-5 x 10(-9) M, as measured by saturation and displacement binding assays. Our findings indicate GDNF is a new neurotrophic factor for developing peripheral neurons and suggest possible non-neuronal roles for GDNF in the developing reproductive system.

Alternative Splicing↗