21 resultados para Testicular biometry

em BORIS: Bern Open Repository and Information System - Berna - Suiça


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Acquired localized hypertrichosis has rarely been reported. Here, we describe a patient with localized hypertrichosis of the pinnae that occurred 4 months after orchiectomy and chemotherapy for a testicular carcinoma. To our knowledge, this is the first case of an acquired hypertrichosis of the pinnae after cancer therapy. We propose that in our patient either hypogonadism or the hormonal imbalance caused by the cancer therapy led to the development of the hairy pinnae, perhaps alongside a genetic predisposition for hairy ears.

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Human sexual determination is initiated by a cascade of genes that lead to the development of the fetal gonad. Whereas development of the female external genitalia does not require fetal ovarian hormones, male genital development requires the action of testicular testosterone and its more potent derivative dihydrotestosterone (DHT). The "classic" biosynthetic pathway from cholesterol to testosterone in the testis and the subsequent conversion of testosterone to DHT in genital skin is well established. Recently, an alternative pathway leading to DHT has been described in marsupials, but its potential importance to human development is unclear. AKR1C2 is an enzyme that participates in the alternative but not the classic pathway. Using a candidate gene approach, we identified AKR1C2 mutations with sex-limited recessive inheritance in four 46,XY individuals with disordered sexual development (DSD). Analysis of the inheritance of microsatellite markers excluded other candidate loci. Affected individuals had moderate to severe undervirilization at birth; when recreated by site-directed mutagenesis and expressed in bacteria, the mutant AKR1C2 had diminished but not absent catalytic activities. The 46,XY DSD individuals also carry a mutation causing aberrant splicing in AKR1C4, which encodes an enzyme with similar activity. This suggests a mode of inheritance where the severity of the developmental defect depends on the number of mutations in the two genes. An unrelated 46,XY DSD patient carried AKR1C2 mutations on both alleles, confirming the essential role of AKR1C2 and corroborating the hypothesis that both the classic and alternative pathways of testicular androgen biosynthesis are needed for normal human male sexual differentiation.

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The sequences of rat testis carbonyl reductase (rCR1) and rat ovary carbonyl reductase (rCR2) are 98% identical, differing only at amino acids 140, 141, 143, 235 and 238. Despite such strong sequence identity, we find that rCR1 and rCR2 have different catalytic constants for metabolism of menadione and 4-benzoyl-pyridine. Compared to rCR1, rCR2 has a 20-fold lower K(m) and 5-fold lower k(cat) towards menadione and a 7-fold lower K(m) and 7-fold lower k(cat) towards 4-benzoyl-pyridine. We constructed hybrids of rCR1 and rCR2 that were changed at either residues 140, 141 and 143 or residues 235 and 238. rCR1 with residues 140, 141 and 143 of rCR2 has similar catalytic efficiency for menadione and 4-benzoyl-pyridine as rCR1. rCR1 with Thr-235 and Glu-238 of rCR2 has the catalytic constants of rCR2, indicating that it is this part of rCR2 that contributes to its lower K(m) for menadione and 4-benzoyl-pyridine. Comparisons of three-dimensional models of rCR1 and rCR2 show how Thr-235 and Glu-238 stabilize rCR2 binding of NADPH and menadione.

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Acute testicular torsion in children is an emergency and has to be diagnosed urgently. Doppler sonography is increasingly used in imaging the acute scrotum. Nevertheless, in uncertain cases, surgical exploration is required. In this study, we attempted to define the role of Doppler sonography in the diagnostic workup of the acutely painful scrotum. All patients admitted between 1999 and 2005 with acute scrotal pain were included. After clinical assessment, patients were imaged by Doppler sonography with a ''high-end'' instrument. In cases of absent arterial perfusion of the testis in Doppler sonography, surgical exploration was carried out. Patients with unaffected perfusion were followed clinically by ultrasound for up to 2 years. Sixty-one infants and children aged 1 day to 17 years (median: 7.9 years) were included. In 14 cases, sonography demonstrated absent central perfusion, with abnormal parenchymal echogenicity in six. Absence of venous blood flow together with reduction of central arterial perfusion was found in one infant. In these 15 patients, surgical exploration confirmed testicular torsion. Among the other 46 patients, we found four cases with increased testicular perfusion and 27 with increased perfusion of the epididymis. In one infant, a testicular tumour was found sonographically, and orchiectomy confirmed diagnosis of a teratoma. Follow-up examinations of the conservatively treated patients showed good clinical outcome with physiologic central perfusion as well as normal echogenic pattern of both testes. No case of testicular torsion was missed. By means of Doppler sonography, an unequivocal statement regarding testicular perfusion was possible in all cases. The initial Doppler diagnosis was confirmed by operative evaluation and follow-up ultrasound. Testicular torsion can therefore be excluded by correctly performed ultrasound with modern equipment.

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Of 54 children with acute lymphoblastic leukemia (ALL) and first hematological recurrence observed between 1985 and 1989, 31 relapsed while still on treatment and 23 after cessation of therapy. Of the former, only one survived. Of the latter, 11 children survived after a minimum follow-up of 25 months. During the same period, a first isolated testicular relapse was observed in nine boys, of whom six survived, and an isolated CNS relapse in eight patients, of whom three survived. As a rule, survivors of a bone marrow or testicular relapse were doing well while those surviving a CNS relapse had considerable neuropsychological sequelae. These results, compared with those of two preceding studies, suggest that with intensification of front-line treatments, it becomes more difficult to rescue children who relapse, particularly those with a bone marrow relapse while on therapy.

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To evaluate a new high-resolution noncontact biometer (Lenstar; Haag-Streit AG, Koeniz, Switzerland) using optical low-coherence reflectometry and to compare the clinical measurements with those obtained from the IOLMaster (Carl Zeiss, Jena, Germany) and the Pachmumeter (Haag-Streit AG).

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To assess the reliability of the Burdizzo procedure for castrating calves and lambs, testicular tissue from 63 bull calves (15 intact and 48 castrated) and 69 male lambs (35 intact and 34 castrated) was collected at slaughter and assessed histologically. The bull calves were castrated at either one, four to five or 12 to 16 weeks of age and the lambs at either one or 10 weeks. There was clear evidence of spermatogenesis in testicular tissue from all the intact animals. In the samples from the calves that had been castrated at 12 to 16 weeks functional testicular tissue was completely lacking. However, there was evidence of spermatogenesis and steroidogenesis in the calves that had been castrated at one week or four to five weeks, respectively. Failure to achieve complete involution of the testicular parenchyma was observed in the majority of lambs, irrespective of the age at which they had been castrated.

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The factors that influence Leydig cell activity currently include peptides such as neuropeptide Y (NPY). In this work we investigated the ability of this compound, injected directly into the testes of adult male rats, to alter testosterone (T) release into the general circulation. At a 5μg/kg dose administered 1h prior to challenge with human chorionic gonadotropin (hCG, 1.0 U/kg, iv), NPY significantly (P<0.01) blunted the T response to this gonadotropin. The inhibitory effect of NPY was observed in animals pretreated with an antagonist to gonadotropin-releasing hormone or not, indicating that the decrease in plasma T found was most likely independent of pituitary luteinizing hormone. However, testicular levels of steroidogenic acute regulatory (STAR) protein or translocator protein (TSPO) in the Leydig cells did not exhibit consistent changes, which suggested that other mechanisms mediated the blunted T response to hCG. We therefore used autoradiography and immunohistochemistry methodologies to identify NPY receptors in the testes, and found them primarily located on blood vessels. Competition studies further identified these receptors as being Y(1), a subtype previously reported to modulate the vasoconstrictor effect of NPY. The absence of significant changes in STAR and TSPO levels, as well as the absence of Y(1) receptors on Leydig cells, suggest that NPY-induced decreases in T release is unlikely to represent a direct effect of NPY on these cells. Rather, the very high expression levels of Y(1) found in testicular vessels supports the concept that NPY may alter gonadal activity, at least in part, through local vascular impairment of gonadotropin delivery to, and/or blunted T secretion from, Leydig cells.

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NPY receptors represent novel molecular therapeutic targets in cancer and obesity. However, the extent of NPY receptor expression in normal human tissues is poorly investigated. Based on the role of NPY in reproductive functions, the NPY receptor expression was studied in 25 normal human testes and, additionally, 24 testicular tumors using NPY receptor autoradiography. In the normal testis, Leydig cells strongly expressed NPY receptor subtype Y2, and small arterial blood vessels Y1. Y2 receptors were found to be functional with agonist-stimulated [(35)S]GTPγS binding autoradiography. Full functional integrity of the NPY system was further suggested by the immunohistochemical detection of NPY peptide in nerve fibers directly adjacent to Leydig cells and arteries. Germ cell tumors expressed Y1 and Y2 on tumor cells in 33% and Y1 on intratumoral blood vessels in 50%. Based on its strong NPY receptor expression in Leydig cells and blood vessels, the normal human testis represents a potentially important physiological and pharmalogical NPY target.

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Background Sedation prior to performance of diagnostic esophagogastroduodenoscopy (EGDE) is widespread and increases patient comfort. But 98% of all serious adverse events during EGDEs are ascribed to sedation. The S3 guideline for sedation procedures in gastrointestinal endoscopy published in 2008 in Germany increases patient safety by standardization. These new regulations increase costs because of the need for more personnel and a prolonged discharge procedure after examinations with sedation. Many patients have difficulties to meet the discharge criteria regulated by the S3 guideline, e.g. the call for a second person to escort them home, to resign from driving and working for the rest of the day, resulting in a refusal of sedation. Therefore, we would like to examine if an acupuncture during elective, diagnostic EGDEs could increase the comfort of patients refusing systemic sedation. Methods/Design A single-center, double blinded, placebo controlled superiority trial to compare the success rates of elective, diagnostic EGDEs with real and placebo acupuncture. All patients aged 18 years or older scheduled for elective, diagnostic EGDE who refuse a systemic sedation are eligible. 354 patients will be randomized. The primary endpoint is the rate of successful EGDEs with the randomized technique. Intervention: Real or placebo acupuncture before and during EGDE. Duration of study: Approximately 24 months. Discussion Organisation/Responsibility The ACUPEND - Trial will be conducted in accordance with the protocol and in compliance with the moral, ethical, and scientific principles governing clinical research as set out in the Declaration of Helsinki (1989) and Good Clinical Practice (GCP). The Interdisciplinary Endoscopy Center (IEZ) of the University Hospital Heidelberg is responsible for design and conduct of the trial, including randomization and documentation of patients' data. Data management and statistical analysis will be performed by the independent Institute for Medical Biometry and Informatics (IMBI) and the Center of Clinical Trials (KSC) at the Department of General, Visceral and Transplantation Surgery, University of Heidelberg.

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Cystic lesions in the testis of children are rare and in most cases benign tumors. However, a preoperative diagnostic work-up could contribute to planning the surgical procedure: orchiectomy in the case of potential malignancy or otherwise a testis-sparing approach. In this study we reviewed our recent cases of benign cystic testicular tumors and the corresponding literature. The different entities are presented with details of the diagnostic work-up, pathology and treatment of these lesions. In all presented cases, organ-preserving treatment was performed. This practice is to be recommended in the case of all prepubertal cystic testicular lesions.

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Following development of the fetal bipotential gonad into a testis, male genital differentiation requires testicular androgens. Fetal Leydig cells produce testosterone that is converted to dihydrotestosterone in genital skin, resulting in labio-scrotal fusion. An alternative 'backdoor' pathway of dihydrotestosterone synthesis that bypasses testosterone has been described in marsupials, but its relevance to human biology has been uncertain. The classic and backdoor pathways share many enzymes, but a 3α-reductase, AKR1C2, is unique to the backdoor pathway. Human AKR1C2 mutations cause disordered sexual differentiation, lending weight to the idea that both pathways are required for normal human male genital development. These observations indicate that fetal dihydrotestosterone acts both as a hormone and as a paracrine factor, substantially revising the classic paradigm for fetal male sexual development.

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BACKGROUND: Testicular tumours are relatively uncommon in infants and children, accounting for only 1-2% of all paediatric solid tumours. Of these approximately 1.5% are Leydig-cell tumours. Further, activating mutations of the luteinizing hormone receptor gene (LHR), as well as of the G protein genes, such as Gsalpha (gsp) and Gialpha (gip2) subunits, and cyclin-dependent kinase gene 4(CDK4) have been associated with the development of several endocrine neoplasms. AIMS/METHODS: In this report, the clinical variability of Leydig-cell tumours in four children is described. The LHR-, gsp-, gip2- and CDK4 genes were investigated to establish the possible molecular pathogenesis of the variable phenotype of the Leydig-cell tumours. RESULTS: No activating mutations in these genes were found in the four Leydig-cell tumours studied. Therefore, the absence of activating mutations in LHR, as well as in both the 'hot spot' regions for activating mutations within the G-alpha subunits and in the regulatory 'hot spot' on the CDK4 genes in these tumours indicates molecular heterogeneity among Leydig-cell tumours. CONCLUSION: Four children with a variable phenotype caused by Leydig-cell tumours are described. A molecular analysis of all the 'activating' genes and mutational regions known so far was performed, but no abnormalities were found. The lessons learnt from these clinically variable cases are: perform ultrasound early and most importantly, consider discrepancies between testicular swelling, tumour size and androgen production.