Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 569
Filtrar
1.
Forensic Toxicol ; 2024 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-38704758

RESUMEN

PURPOSE: Inadvertent and/or unknowing exposure to drugs and drug residues has been frequently debated in situations of so-called adverse analytical finding (AAF) in the context of sports drug testing programs. Transfer of drug residues via unprotected intercourse is a conceivable scenario but scientific data and authentic case reports are scarce. Herein, investigations into two AAFs with the peroxisome proliferator-activated receptor delta (PPARδ) agonist GW1516 are reported and discussed. METHODS: To probe for a contamination scenario involving sexual intercourse, two assays were used to determine semenogelin in human urine, with one employing an immunochromatographic lateral flow approach and another based on liquid chromatography-tandem mass spectrometry. Further, drug-residue testing using patients' ejaculate was conducted by utilizing liquid chromatography in conjunction with a triple quadrupole mass spectrometer, followed by re-analysis of suspect samples (i.e., samples indicating the presence of relevant compounds) using high resolution/high mass accuracy mass spectrometry. RESULTS: In one case, but not the other, the possibility of intimate contact as the source of the AAF was confirmed after a thorough investigation of potential contamination scenarios. Subsequent research revealed analytical evidence for the presence of seminal fluid in one of the female athlete's doping control urine samples, and the analysis of clinical ejaculate specimens provided first data on an authentic concentration level of GW1516 and its metabolites in human seminal fluid. CONCLUSIONS: The combined facts substantiate the possibility of an AAF caused by unprotected sexual intercourse and the plausibility of the case-related arguments.

2.
Andrology ; 8(6): 1506-1511, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-31639279

RESUMEN

The term Late-onset hypogonadism (LOH) was coined in 2002 and defined as a disease entity in the ISA, ISSAM, EAU, EAA and ASA endorsed Recommendations for Investigation, Treatment and Monitoring of LOH (2005 and 2008) as 'a clinical and biochemical syndrome associated with advancing age, characterized by symptoms and a deficiency in serum testosterone (T)'. LOH was classified as a combined primary and secondary hypogonadism since the endocrine capacity of the testes and the pituitary are impaired. Symptoms of LOH include loss of libido, erectile dysfunction, loss of muscle mass, increased body fat, anemia, osteoporosis, depressed mood, decreased vitality, sweating, and hot flushes. Since these symptoms may also have origins other than LOH, exclusion of other disease entities and subnormal serum T levels are considered prerequisites for the diagnosis and possible treatment of LOH. However, during following years these guidelines were often neglected and, especially in the USA, indiscriminate prescribing of T was widely practised so that the US FDA warned against such irresponsible behavior. In Europe, T prescribing remained largely restricted to LOH as defined above. Nevertheless, a discussion started whether LOH really exists or is only a consequence of age-related comorbidities. Numerous studies have helped to clarify the situation, in particular, the European Male Aging Study (EMAS) and the US-initiated 7 T trials. Consequently, the newest US Endocrine Society Practice Guideline on T treatment (2018) includes advanced age as a cause of organic hypogonadism and recommends that 'in men >65 years who have symptoms or conditions suggestive of T deficiency … and consistently and unequivocally low morning T concentrations we suggest that clinicians offer T therapy on an individualised basis after explicit discussion of the potential risks and benefits'. Thus, the concept of LOH as conceived two decades ago has weathered criticism and survived the times.


Asunto(s)
Eunuquismo/tratamiento farmacológico , Terapia de Reemplazo de Hormonas , Testosterona/uso terapéutico , Edad de Inicio , Anciano , Animales , Biomarcadores/sangre , Toma de Decisiones Clínicas , Eunuquismo/sangre , Eunuquismo/diagnóstico , Eunuquismo/epidemiología , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Testosterona/efectos adversos , Testosterona/sangre , Testosterona/deficiencia , Resultado del Tratamiento
3.
Andrology ; 6(4): 525-531, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29931814

RESUMEN

Klinefelter syndrome (KS) and undescended testes (UDT) are known etiologies for non-obstructive azoospermia (NOA), and coexistence of both etiologies is not uncommon. Patients with both KS and a history of UDT are therefore considered to have extremely reduced chances for paternity. We aimed to analyze the impact of previous surgically corrected unilateral or bilateral UDT on sperm retrieval rates (SRRs) by microsurgical testicular sperm extraction (mTESE) in azoospermic men with KS. Age, testicular volumes, and hypothalamo-pituitary-gonadal axis function were investigated in relation to SRRs in 29 non-mosaic KS patients (47,XXY) with a history of UDT (group 1) who underwent mTESE between 2008 and 2016 in our center and compared to the data of age- and serum testosterone-matched non-mosaic KS controls with eutopic testes at birth (group 2), and to those of 51 men with NOA and a normal male karyotype (46,XY), but previous UDT (group 3). SRRs in KS patients with surgically corrected UDT during childhood were comparable to SRRs of KS patients with eutopic testes at birth: 31% (35% in unilateral and 22% in bilateral UDT) vs. 38% (p = 0.581). SRRs and Leydig cell function in group 1 were negatively correlated with age. Significantly higher SRRs (66%) were found in euploid azoospermic men with surgically corrected UDT (p < 0.001). A history of UDT does not preclude chances for future fatherhood in young azoospermic males with KS. In one of three men with previous unilateral UDT and in one of 4-5 in those with previous bilateral UDT, spermatozoa can be harvested by mTESE during late adolescence or young adulthood for immediate or future use in assisted reproduction.


Asunto(s)
Criptorquidismo/complicaciones , Síndrome de Klinefelter/complicaciones , Recuperación de la Esperma , Adolescente , Adulto , Azoospermia/etiología , Humanos , Masculino , Microcirugia/métodos , Estudios Retrospectivos , Adulto Joven
4.
Andrology ; 5(3): 516-526, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28189123

RESUMEN

Although several progestins have been tested for hormonal male contraception, the effects of dosage and nature of various progestins on gonadotropin suppression combined with and without additional testosterone has not been performed in a comparative trial. The aim of this study was to evaluate the differential impact of four oral or transdermal progestins on the suppression of gonadotropins in healthy men: oral: cyproterone acetate (CPA), levonorgestrel (LNG), norethisterone acetate (NETA), and transdermal: Nestorone® (NES), all in combination with transdermal testosterone (T). Randomized clinical trial testing was performed with four progestins at two doses each. After a 2-week progestin-only treatment, transdermal T was added for further 4 weeks and was followed by a 3-week recovery period. Progestin-dose per day: CPA 10 mg/20 mg, NES 2 mg/3 mg/dose e.g. 200/300 µg/day absorbed, NETA 5 mg/10 mg, LNG 120 µg/240 µg. From an andrology outpatient clinic, 56 healthy men aged 18-50 years, with body mass index ≤33 kg × m-2 were included in the study. Serum concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were studied. Secondary outcome measure included were serum testosterone concentrations, sperm concentrations, and safety parameters. Intergroup comparisons demonstrated that CPA and LNG had the strongest effect on LH/FSH suppression. Nevertheless, every substance showed significant inhibitory effects on gonadotropin secretion, especially in combination with transdermal T. A decrease in hematocrit and insulin sensitivity as well as cholesterol subfractions and triglycerides was uniformly seen for every group. The combination of oral or transdermal progestins with a transdermal testosterone preparation is able to suppress gonadotropins. Further dose titration studies with sperm suppression as an end-point should be conducted to determine the lowest effective dose for hormonal male contraception.


Asunto(s)
Anticonceptivos Masculinos/administración & dosificación , Acetato de Ciproterona/administración & dosificación , Levonorgestrel/administración & dosificación , Noretindrona/análogos & derivados , Norprogesteronas/administración & dosificación , Testosterona/administración & dosificación , Adolescente , Adulto , Anticoncepción/métodos , Anticonceptivos Masculinos/efectos adversos , Acetato de Ciproterona/efectos adversos , Hormona Folículo Estimulante/sangre , Humanos , Levonorgestrel/efectos adversos , Hormona Luteinizante/sangre , Masculino , Persona de Mediana Edad , Noretindrona/administración & dosificación , Noretindrona/efectos adversos , Acetato de Noretindrona , Norprogesteronas/efectos adversos , Progestinas , Espermatozoides/efectos de los fármacos , Testosterona/efectos adversos , Testosterona/sangre , Parche Transdérmico , Adulto Joven
6.
Andrology ; 4(6): 1178-1186, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27611179

RESUMEN

Patients with Klinefelter's syndrome experience progressive testicular degeneration resulting in impaired endocrine function and azoospermia. What proportion of adolescents develop testosterone deficiency during puberty and how many have spermatozoa in their semen is unclear to date. We aimed to investigate testicular function during puberty and young adulthood in patients with Klinefelter's syndrome and to assess testosterone effects in target tissues. The clinical data of 281 patients with non-mosaic Klinefelter's syndrome aged 10-25 years without previous testosterone replacement were reviewed. In late pubertal adolescents, semen analyses were evaluated, and testicular volumes, hormone and haemoglobin (Hb) levels, the number of CAG repeats and final height data were compared to those of 233 age-matched controls with pubertal gynaecomastia. Spontaneous pubertal virilisation to Tanner stages IV-V occurred. Serum T levels ≥10 nmol/L were reached in 62% of patients with Klinefelter's syndrome and in 85% of controls at ages 15-25 (TKFS : 12.2 ± 5.4 vs. TC : 16.6 ± 7.2 nmol/L). LHKFS levels were elevated >10 U/L in 84%, and normal in all controls (LHKFS : 18.6 ± 12.2 vs. LHC : 3.5 ± 1.6 U/L). In nine of 130 (7%) adolescents with Klinefelter's syndrome, spermatozoa (oligozoospermia) were found in semen; all had T levels >7 nmol/L and eight of nine had LH levels ≤18 U/L, while their hormone levels, number of CAG repeats and testicular volumes were not different from those of adolescents with azoospermia. Controls had normal sperm concentrations in 73% (46/63). Semen volumesKFS were normal in 55% vs. 78% in controls; HbKFS was normal in 89% (HbC : 97%). Mean final heightKFS was 185 ± 8 cm vs. 181 ± 7 cm in controls. Hypergonadotropic hypogonadism develops during early puberty in adolescents with Klinefelter's syndrome and remains compensated in over 60% during ages 15-25, with sufficient testosterone secretion for spontaneous accomplishment of pubertal development. Spermatozoa in semen are rare and associated with T levels >7 nmol/L. Parameters reflecting androgen deficiency in target tissues may help to optimise timing of testosterone substitution, which should preferably not be initiated before fertility status has been clarified.


Asunto(s)
Hipogonadismo/fisiopatología , Síndrome de Klinefelter/fisiopatología , Pubertad/metabolismo , Espermatozoides/citología , Testículo/fisiopatología , Testosterona/sangre , Adolescente , Adulto , Estatura/fisiología , Niño , Hormona Folículo Estimulante/sangre , Humanos , Hipogonadismo/sangre , Síndrome de Klinefelter/sangre , Síndrome de Klinefelter/patología , Hormona Luteinizante/sangre , Masculino , Tamaño de los Órganos/fisiología , Semen/citología , Análisis de Semen , Espermatogénesis/fisiología , Testículo/patología , Adulto Joven
8.
Andrology ; 4(1): 87-94, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26779870

RESUMEN

Germ cell and Sertoli cell proliferation and maturation in human testes occur in three main waves, during the late fetal and early neonatal period and at early puberty. They are triggered by periods of increased activity of the hypothalamic-pituitary-gonadal (HPG) axis. In hypogonadotropic hypogonadism (HH), these processes are variably disturbed. The objective of this study was to explore whether success of gonadotropin replacement in HH men is predictable by the origin of HH, indicating time of onset and severity of GnRH/gonadotropin deficiency. The data of 51 adult HH patients who had undergone one cycle of hCG/FSH treatment were reviewed. Five groups were established, according to the underlying HH origin. Therapeutic success by final bi-testicular volumes (BTVs) final sperm concentrations (SC) and conception rates were compared and related to baseline parameters, indicative of the degree of HPG-axis disruption. Overall, BTVs rose from 13 ± 15 to 27 ± 15 mL, spermatogenesis was induced in 98%, with mean SCs of 15 ± 30 mill/mL, spontaneous pregnancies in 37% and additional 18% via intracytoplasmic sperm injection. Kallmann syndrome patients had the poorest responses (BTV: 16.9 ± 10 mL; SC: 3.5 ± 5.6 mill/mL), followed by patients with congenital/infancy-acquired multiple pituitary hormone deficiencies (MPHD) and patients with HH+absent puberty (BTV: 21 ± 14/24 ± 9 mL; SC: 5.5 ± 6.5/ 14.5 ± 23.8 mill/mL). HH men with pubertal arrest and with post-pubertally acquired MPHD had the best results (BTV: 36 ± 14/38 ± 16 mL; SC: 25.4 ± 34.2/29.9 ± 50.5 mill/mL). Earlier conception after 20.3 ± 11.5 months (vs. 43.1 ± 43.8; p = 0.047) of gonadotropin treatment with higher pregnancy rates (62% vs. 42%) was achieved in the two post-pubertally acquired HH subgroups, compared to the three pre-pubertally acquired. Therapeutic success was higher in patients without previously undescended testes, with higher baseline BTVs (pre- vs. post-pubertal HH: 5 ± 4 mL vs. 26 ± 16 mL; p < 0.0001) and higher baseline inhibinB levels (pre- vs. post-pubertal HH: 16.6 vs. 144.5 pg/mL; p = 0.0004). The cause of HH is a valuable predictor of outcome of gonadotropin replacement in adults.


Asunto(s)
Gonadotropina Coriónica/uso terapéutico , Hormona Folículo Estimulante/uso terapéutico , Terapia de Reemplazo de Hormonas/métodos , Hipogonadismo/tratamiento farmacológico , Síndrome de Kallmann/tratamiento farmacológico , Espermatogénesis/efectos de los fármacos , Adulto , Proliferación Celular/fisiología , Criptorquidismo , Hormona Liberadora de Gonadotropina/deficiencia , Humanos , Inhibinas/metabolismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Células de Sertoli/fisiología , Maduración Sexual/fisiología , Recuento de Espermatozoides , Inyecciones de Esperma Intracitoplasmáticas , Espermatozoides/fisiología
9.
Andrology ; 3(5): 882-7, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26266675

RESUMEN

In pre-pubertal boys ≥ 14 years, the differentiation between constitutional delay of growth and puberty (CDGP) and hypogonadotropic hypogonadism (HH) is challenging, as current diagnostic tools have limitations in sensitivity and specificity. The aim of this study was to assess the usefulness of markers of gonadal activity, growth axis activation and adrenarche in differentiation between pre-pubertal CDGP and HH. This retrospective study was carried out between 2006 and 2015 in an academic out-patient referral centre. The clinical data of 94 boys, aged 13.9-23.2 years and referred for "pubertal delay" were reviewed. Definite diagnoses were established on initial work-up and clinical follow-up: 24 boys were diagnosed with HH, 22 boys with CDGP, pre-pubertal (PP CDGP) at referral and 28 boys with CDGP, early pubertal at referral (EP CDGP), the latter serving as control group. Twenty patients were excluded from evaluation because of previous sex steroid treatment or associated chronic disease. Inhibin B and AMH were measured in all (n = 74); INSL3, IGF1, IGFBP3 and DHEAS in a subset of patients (n = 45) in serum of first presentation. Inhibin B and AMH were higher in boys with PP CDGP than in boys with HH: inhibin B: 87.6 ± 42.5 vs. 19.8 ± 13.9 pg/mL; p < 0.001; AMH: 44.9 ± 27.1 vs. 15.4 ± 8.3 ng/mL; p < 0.001. Receiver operating characteristics (ROC) for the diagnosis of PPCDGP vs. HH (inhibin B ≥ 28.5 pg/mL): sensitivity: 95%, specificity: 75%; AUC: 0.955. In combination with an AMH cut-off ≥20 ng/mL the specificity increased to 83%. INSL3, IGF1, IGFBP3 and DHEAS levels were not different. In boys with EP CDGP, inhibin B and IGF1 levels were highest (138.7 ± 59.9 pg/mL/289.7 ± 117 ng/mL), whereas AMH levels were lowest (11.7 ± 9.1 ng/mL). Sertoli cell markers are helpful for establishing a prognosis, whether a boy with pubertal delay will enter puberty spontaneously, whereas Leydig cell, growth and adrenal markers are not.


Asunto(s)
Adrenarquia/sangre , Biomarcadores/sangre , Hipogonadismo/sangre , Pubertad Tardía/sangre , Maduración Sexual/fisiología , Adolescente , Adulto , Hormona Antimülleriana/sangre , Sulfato de Deshidroepiandrosterona/sangre , Humanos , Hipogonadismo/diagnóstico , Inhibinas/sangre , Insulina/sangre , Factor I del Crecimiento Similar a la Insulina/metabolismo , Células Intersticiales del Testículo/metabolismo , Masculino , Proteínas , Pubertad Tardía/diagnóstico , Estudios Retrospectivos , Células de Sertoli/metabolismo , Adulto Joven
10.
Andrology ; 2(2): 275-81, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24574169

RESUMEN

Klinefelter syndrome (KS, 47,XXY) is associated with low serum testosterone (T), long thought to arise from disturbed steroidogenesis in Leydig cells. However, intratesticular testosterone (ITT) concentrations were recently found to be normal in a KS mouse model(41,XXY*). So far, nothing was known about ITT concentrations in human patients with KS. Therefore, ITT, sex hormone-binding globulin (SHBG) and histological parameters were measured in human testicular biopsies of 11 KS patients, 30 azoospermic patients with Sertoli-cell-only syndrome and nine men with normal spermatogenesis as controls. ITT concentrations showed an overall pronounced excess over intratesticular SHBG in molar terms and were significantly increased in men with KS despite of reduced serum T levels. While the ratio of ITT/serum T was markedly increased in KS, the ITT/LH-ratio was comparable between all groups. After finding significantly increased ITT levels in men with KS, a finding even more striking than in the 41,XXY* KS mouse model, we set out to find a possible 'vascular' explanation for the lack of T release into the testicular blood stream. In testis biopsies from patients,reliable analysis of the vessels is, however, not possible because of the bias resulting from the dissection technique requiring avoidance of larger blood vessels to prevent bleeding. Consequently, the blood vessel constitution was evaluated in whole testis sections from adult male 41,XXY* and 40,XY*mice (n=5, each). Indeed, the blood vessel/testes surface ratio correcting for the smaller testes of XXY*mice was significantly lower in these mice compared with XY*controls. In conclusion, testicular T production does not seem to be impaired in men with KS. On the contrary, ITT concentrations are increased, but not because of increased SHBG activity. The data from the mouse model let us speculate that a reduced vascular bed might be involved in lower release of T into the blood stream.


Asunto(s)
Síndrome de Klinefelter/metabolismo , Globulina de Unión a Hormona Sexual/metabolismo , Testículo/irrigación sanguínea , Testículo/metabolismo , Testosterona/metabolismo , Adulto , Animales , Azoospermia , Humanos , Masculino , Ratones , Síndrome de Sólo Células de Sertoli , Espermatogénesis , Testosterona/sangre
11.
Artículo en Alemán | MEDLINE | ID: mdl-24337123

RESUMEN

Although male reproductive functions are impaired in about half of the infertile couples seeking offspring, even today the examination and treatment of the male partner continues to be neglected. Despite the lack of evidence for a "sperm crisis", so highly touted in the press, the public remains worried, while the fact that male fertility declines beyond the age of 40 years and is accompanied by increasing genetic risks for the offspring goes largely unnoticed. In addition to a thorough physical examination supplemented by imaging techniques such as ultrasonography of the scrotal organs, semen analysis according to WHO guidelines, hormone determinations, and cyto- and molecular genetic analyses form part of the routine investigation of the infertile male. Few disorders have become subjects of rational treatment, such as hypogonadotropic hypogonadism with gonadotropins or GnRH, treatment of sexually transmitted diseases by antibiotics, and microsurgical reconstruction of blocked seminal ducts. Early treatment of maldescended testes in boys or changing lifestyle (e.g., discontinuation of smoking) are important preventive measures. In the age of evidence-based medicine, most empirical treatments have been demonstrated to be ineffective. Thus, pregnancy rates from patients with varicocele who underwent long-practiced surgical or radiologic interventional therapy were not different from those of patients receiving counseling. At present, in cases of non-obstructive azoospermia or severe oligoasthenoteratozoospermia, intracytoplasmic sperm injection (ICSI) using single sperm derived from semen or extracted from testicular biopsy tissue (TESE) represents the most successful treatment modality, although it remains symptomatic and not curative.


Asunto(s)
Predicción , Infertilidad Masculina/diagnóstico , Infertilidad Masculina/terapia , Técnicas de Diagnóstico Molecular/tendencias , Análisis de Semen/tendencias , Inyecciones de Esperma Intracitoplasmáticas/tendencias , Ultrasonografía/tendencias , Medicina Basada en la Evidencia , Humanos , Masculino
12.
Exp Clin Endocrinol Diabetes ; 120(2): 73-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22068615

RESUMEN

BACKGROUND: Polycystic ovary syndrome (PCOS) is a frequent heterogenic disorder with a familial background. Androgenic effects, determining the clinical features of the syndrome, are mediated by the androgen receptor (AR), whose activity is modulated by a genetic polymorphism. We investigated the role of the CAG repeat polymorphism of the androgen receptor in PCOS. METHODS: In the infertility unit of a university clinic, 72 PCOS patients were compared with 179 ovulatory controls undergoing a standardized diagnostic work-up. The number of CAG repeats was determined by PCR, labelling with IR-800 and PAGE. X-chromosome inactivation was assessed by a methylation-sensitive assay. RESULTS: Compared to controls, PCOS patients displayed a shorter mean CAG repeat length, encoding for higher AR activity (P=0.001). CAG repeat length correlated inversely with oligomenorrhea, a central androgen dependent feature of the syndrome (P=0.005). In a binomial regression analysis including BMI, LH and free testosterone, CAG repeat length was identified as an independent risk factor for PCOS (P=0.002). CONCLUSIONS: The CAG repeat polymorphism could constitute one of the genetic factors modulating the syndrome's phenotype, contributing to its clinical heterogeneity and associated metabolic consequences.


Asunto(s)
Síndrome del Ovario Poliquístico/genética , Receptores Androgénicos/genética , Expansión de Repetición de Trinucleótido/genética , Adulto , Secuencia de Bases , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Humanos , Ciclo Menstrual/genética , Ciclo Menstrual/fisiología , Fenotipo , Síndrome del Ovario Poliquístico/etiología , Síndrome del Ovario Poliquístico/metabolismo , Polimorfismo Genético/fisiología , Receptores Androgénicos/fisiología , Factores de Riesgo , Inactivación del Cromosoma X/fisiología , Adulto Joven
13.
Int J Androl ; 34(6 Pt 1): 556-67, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21651568

RESUMEN

Hormonal male contraception based on testosterone alone or on a combination of testosterone with a gestagen has been shown to suppress spermatogenesis effectively and to be fully reversible. However, clinical studies to date have only included volunteers with so-called 'normal' semen values by WHO standards. As a male contraceptive should be available to all interested men regardless of their semen parameters, we investigated how volunteers with subnormal semen parameters would respond to hormonal male contraception. During a 34-week treatment phase, the volunteers received injections of 1000 mg testosterone undecanoate in weeks 0, 6, 14 and 24. This was followed by a 24-week recovery and follow-up period. As it was not known whether men with subnormal semen parameters would recover to starting levels, cryopreservation of semen was offered to all subnormal volunteers. Twenty-three men with normal semen parameters and 18 with sperm counts below 20 million completed the trial. The normal volunteers showed the expected response with 17 suppressing sperm counts below 1 million/ejaculate (13 showing azoospermia) and six not-suppressing below 1 million sperm/ejaculate. By the end of the recovery period, all sperm counts had returned to the range of starting values. The subnormal group showed a similar pattern with 13 of 18 (= 72%) men suppressing below 1 million/ejaculate (8/18 = 44% showing azoospermia) and the remaining 5 of 18 (= 28%) not-suppressing sperm counts below 1 million/ejaculate. All sperm counts returned to the starting range. The study shows that in Caucasian men with normal sperm counts as well as in men with subnormal sperm counts, testosterone alone can produce azoospermia in about half and suppression below one million in about two-thirds of the volunteers. The same proportion of men in both groups appears to require an additional gestagen for full contraceptive protection. Most importantly, regarding suppressibility and reversibility, volunteers with normal and subnormal sperm counts display the same pattern.


Asunto(s)
Anticonceptivos Masculinos/uso terapéutico , Semen , Adulto , Estudios de Casos y Controles , Ensayo de Inmunoadsorción Enzimática , Hormonas Esteroides Gonadales/sangre , Humanos , Masculino , Persona de Mediana Edad , Receptores Androgénicos/genética
14.
Reproduction ; 141(4): 481-90, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21292727

RESUMEN

Improvements in cancer survival rates have renewed interest in the cryopreservation of ovarian tissue for fertility preservation. We used the marmoset as a non-human primate model to assess the effect of different cryoprotectives on follicular viability of prepubertal compared to adult ovarian tissue following xenografting. Cryopreservation was performed with dimethylsulfoxide (DMSO), 1,2-propanediol (PrOH), or ethylene glycol (EG) using a slow freezing protocol. Subsequently, nude mice received eight grafts per animal from the DMSO and the PrOH groups for a 4-week grafting period. Fresh, cryopreserved-thawed, and xenografted tissues were serially sectioned and evaluated for the number and morphology of follicles. In adult tissue, the percentage of morphologically normal primordial follicles significantly decreased from 41.2 ± 4.5% (fresh) to 13.6 ± 1.8 (DMSO), 9.5 ± 1.7 (PrOH), or 6.8 ± 1.0 (EG) following cryopreservation. After xenografting, the percentage of morphologically normal primordial (26.2 ± 2.5%) and primary follicles (28.1 ± 5.4%) in the DMSO group was significantly higher than that in the PrOH group (12.2 ± 3 and 5.4 ± 2.1% respectively). Proliferating cell nuclear antigen (PCNA) staining suggests the resumption of proliferative activity in all cellular compartments. In prepubertal tissues, primordial but not primary follicles display a similar sensitivity to cryopreservation, and no significant differences between DMSO and PrOH following xenografting were observed. In conclusion, DMSO shows a superior protective effect on follicular morphology compared with PrOH and EG in cryopreserved tissues. Xenografting has confirmed better efficacy of DMSO versus PrOH in adult but not in prepubertal tissues, probably owing to a greater capacity of younger animals to compensate for cryoinjury.


Asunto(s)
Criopreservación , Crioprotectores/efectos adversos , Supervivencia de Injerto/efectos de los fármacos , Folículo Ovárico/fisiología , Folículo Ovárico/trasplante , Ovario , Maduración Sexual/fisiología , Animales , Conducta de Elección , Crioprotectores/farmacología , Dimetilsulfóxido/efectos adversos , Dimetilsulfóxido/farmacología , Resistencia a Medicamentos/fisiología , Glicol de Etileno/efectos adversos , Glicol de Etileno/farmacología , Femenino , Supervivencia de Injerto/fisiología , Folículo Ovárico/efectos de los fármacos , Primates , Propilenglicol/efectos adversos , Propilenglicol/farmacología , Trasplante Heterólogo
15.
Int J Androl ; 34(4): 291-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20609027

RESUMEN

The clinical workup of the infertile male with azoospermia aims at determining the aetiology and estimating the chances of finding spermatozoa by testicular sperm extraction (TESE). To establish prognostic criteria, 1583 consecutive patients with azoospermia consulting the Centre of Reproductive Medicine and Andrology, Münster, a tertiary referral centre, between 1976 and 2009 comprising 9.8% of all patients providing a semen sample were included in this retrospective analysis. The frequencies of diagnoses were as follows: 21% genetic causes (14% Klinefelter syndrome, 1% other chromosomal aberrations, 2% Y-chromosomal microdeletions, 1% hypogonadotropic hypogonadism, 3% congenital bilateral absence of the vas deferens), 31% current or former maldescended testes, varicocele, urogenital infections, 15% malignancies, 11% obstructions, 7% endocrine or other chronic diseases and 12% idiopathic azoospermia. Receiver-operating characteristic curves for chances of finding spermatozoa by testicular biopsy were calculated for testicular volume, serum follicle-stimulating hormone (FSH) and the seminal markers α-glucosidase, fructose and zinc where these data were available (N=283). Histograms of the seminal markers comparing data from men with obstructive azoospermia and normozoospermia visualize their discriminating power. Evidence-based threshold values for high chances of positive testicular biopsy serving as surrogate marker for TESE were derived from the subgroup of men with obstructive azoospermia for testicular volume (≥21mL), FSH (≤10U/L) and seminal α-glucosidase (≤18mU/ejaculate). Fructose and zinc could not predict the chances of finding spermatozoa upon biopsy. Based on these three parameters, positive biopsy and presumably TESE success can be quickly and reliably estimated in everyday practice with the colour-coded figures constructed from these data. As a seminal α-glucosidase reference limit of 18mU/ejaculate can also be used to diagnose congenital bilateral absence of the vas deferens, α-glucosidase (rather than seminal fructose) should be determined as part of the clinical routine when counselling patients before testicular biopsy.


Asunto(s)
Azoospermia/patología , Biopsia , Azoospermia/genética , Estudios de Cohortes , Humanos , Cariotipificación , Masculino
16.
Handb Exp Pharmacol ; (198): 197-223, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20839093

RESUMEN

The principle of hormonal male contraception based on suppression of gonadotropins and spermatogenesis has been established over the last three decades. All hormonal male contraceptives use testosterone, but only in East Asian men can testosterone alone suppress spermatogenesis to a level compatible with contraceptive protection. In Caucasians, additional agents are required of which progestins are favored. Current clinical trials concentrate on testosterone combined with norethisterone, desogestrel, etonogestrel, DMPA, or nestorone. The first randomized, placebo-controlled clinical trial performed by the pharmaceutical industry demonstrated the effectiveness of a combination of testosterone undecanoate and etonogestrel in suppressing spermatogenesis in volunteers.


Asunto(s)
Anticoncepción , Anticonceptivos Masculinos/farmacología , Anticonceptivos Hormonales Orales/farmacología , Andrógenos/farmacología , Animales , Humanos , Masculino , Progestinas/farmacología , Receptores LHRH/antagonistas & inhibidores
17.
Int J Androl ; 33(1): e240-8, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19863670

RESUMEN

Sperm chromatin compaction in the sperm head is achieved when histones are replaced by protamines during spermatogenesis. Haploinsufficiency of the protamine 1 (PRM1) or PRM2 gene causes infertility in mice. However, the published data remain inconclusive about a role of PRM1/2 variants in male infertility and their association with semen parameters. By full sequence analysis, we assessed the frequency of sequence variations in PRM1 and PRM2 in three groups of Caucasian patients with idiopathic teratozoospermia and normal (n = 88) or reduced sperm concentration (n = 83) and in men with a high percentage of normal sperm morphology and normal concentrations (n = 77). Two rare (c.54G>A and c.102G>T) and one common SNP (c.230A>C) were identified in PRM1. In PRM2, some rare heterozygous mutations and the two common intronic SNPs 298G>C and 373C>A were detected. None of the PRM1/2 variants was associated with teratozoospermia or individually with other semen parameters. However, significant linkage disequilibrium was detected between the common SNPs of PRM1 and PRM2 which formed haplotypes. Analysis of the pooled group (n = 248) revealed that homozygous carriers of the common haplotype ACC had a twofold higher sperm concentration and count than men lacking this haplotype, with sperm counts of heterozygotes for ACC being midway between the homozygotes. This markedly decreased sperm output might either be caused by spermatozoa lacking the ACC haplotype not being viable, or subject to negative selection. In addition, a significant deviation from Hardy-Weinberg-Equilibrium of these SNPs might indicate natural selection in favour of the ACC allele which leads to higher sperm output and therefore better fertility. In conclusion, for the first time we describe an association of a common haplotype formed by PRM1 and PRM2 with sperm output in a large group of men.


Asunto(s)
Protaminas/genética , Adulto , Cromatina/metabolismo , Fertilidad/genética , Genes , Haplotipos , Heterocigoto , Histonas/genética , Humanos , Infertilidad Masculina/genética , Masculino , Persona de Mediana Edad , Mutación , Polimorfismo de Nucleótido Simple/genética , Espermatogénesis/genética , Espermatozoides
19.
Int J Androl ; 32(3): 242-54, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18070047

RESUMEN

In the treatment of male infertility by intra-cytoplasmic injection of spermatozoa (ICSI) extracted from testicular tissue (TESE), the high incidence of negative TESE outcome calls for non-invasive prognostic methods. Literature suggests that seminal haploid germ cell detection could be one. For this purpose, a multi-parametric stringent flow cytometric method was applied to 50 TESE patients for the quantification of ejaculated germ cells. Cells from 50 ejaculates were identified and quantified as spermatozoa (HC, highly condensed), round spermatids (1N), primary spermatocytes (SPC) (4N) or diploid cells (2N, including somatic and non-testicular cells) by their DNA and mitochondria staining and laser scatter characteristics, and compared with testicular biopsy histology and TESE outcome. Whereas 96% of patients displayed a diploid peak in the distribution histograms, the HC, 1N and 4N peaks were absent from the majority of samples. In 13 ejaculates, either a HC or 1N or 4N peak, or a combination of these, was discernible. Although seminal germ cell numbers bore no overall association with elongated spermatids (ES) in histology or spermatozoa retrieval in TESE outcome, 4N cells per ejaculate were correlated with the percentage of tubule sections showing SPC as the most advanced germ cells. The incidence of HC peaks was higher in patients showing some ES in histology or sperm retrieval than in the sperm-negative groups. In groups with suspected obstruction showing nearly full spermatogenesis and maximal sperm retrieval, there was no incidence of a HC peak. Germ cell peaks were associated with germ cell degeneration noted in testicular histology. In conclusion, seminal germ cells cannot provide good prognosis for TESE, although their presence could indicate the spermatogenic activity in the testis.


Asunto(s)
Azoospermia/patología , Semen/citología , Espermatozoides/patología , Testículo/patología , Biopsia , Citometría de Flujo , Hormona Folículo Estimulante/sangre , Humanos , Infertilidad Masculina/patología , Hormona Luteinizante/sangre , Masculino , Pronóstico , Prolactina/sangre , Análisis de Semen , Inyecciones de Esperma Intracitoplasmáticas/métodos , Testosterona/sangre
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA