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1.
Environ Int ; 89-90: 166-73, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26863184

RESUMEN

BACKGROUND: In the testis, steroid hormones play an important role in spermatogenesis, the production of semen, and the maintenance of secondary sex characteristics and libido. They may also play a role as a target for substances called endocrine disruptors (EDs). As yet, however, no complex study has been conducted evaluating the relationships between EDs and the steroid spectrum in the plasma and seminal plasma. OBJECTIVES: To shed more light into mechanisms of EDs and the effects of bisphenol A (BPA) and polychlorinated biphenyls (PCBs) on human spermatogenesis and steroidogenesis. METHODS: We determined BPA and 11 steroids in the plasma and seminal plasma of 191 men with different degrees of fertility, using a newly developed liquid-chromatography mass spectrometry method. Concurrently, plasma levels of 6 congeners of PCBs, gonadotropins, selenium, zinc and homocysteine were measured. Partial correlations adjusted for age, BMI and abstinence time were performed to evaluate relationships between these analytes. RESULTS: Seminal BPA, but not plasma BPA, was negatively associated with sperm concentration (r=-0.198; p=0.009), sperm count (r=-0.178; p=0.018) and morphology (r=-0.160; p=0.044). Divergent and sometimes opposing associations of steroids and BPA were found in both body fluids. The sum of PCB congeners was negatively associated with testosterone, free testosterone, the free androgen index and dihydrotestosterone in plasma. CONCLUSION: BPA may negatively contribute to the final state of sperm quality. Moreover, our data indicate that BPA influences human gonadal and adrenal steroidogenesis at various steps. Environmental levels of PCBs negatively correlated with androgen levels, but surprisingly without negative effects on sperm quality.


Asunto(s)
Compuestos de Bencidrilo/análisis , Disruptores Endocrinos/análisis , Hormonas Esteroides Gonadales/sangre , Infertilidad Masculina/epidemiología , Fenoles/análisis , Bifenilos Policlorados/análisis , Semen/química , Espermatogénesis/efectos de los fármacos , Adulto , Compuestos de Bencidrilo/sangre , Compuestos de Bencidrilo/toxicidad , Cromatografía Liquida/métodos , Disruptores Endocrinos/sangre , Disruptores Endocrinos/toxicidad , Humanos , Infertilidad Masculina/sangre , Infertilidad Masculina/inducido químicamente , Masculino , Fenoles/sangre , Fenoles/toxicidad , Bifenilos Policlorados/sangre , Bifenilos Policlorados/toxicidad , Semen/efectos de los fármacos , Recuento de Espermatozoides , Espermatozoides/química , Espermatozoides/efectos de los fármacos , Espermatozoides/patología , Testosterona/sangre
2.
Syst Biol Reprod Med ; 61(4): 245-50, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26043179

RESUMEN

Male infertility is a serious problem in an increasing number of couples. We report an infertile man with non-obstructive azoospermia and karyotype 45,XY,rob(14;22). The immunofluorescence analysis of his testicular tissue using antibodies to SYCP1, SYCP3, HORMAD2, MLH1, and centromeres showed delayed synapsis of the chromosomes involved in the translocation, a varying extent of trivalent asynapsis and its association with sex chromosomes. The mean frequency of meiotic recombination per cell was within the range of normal values. Fluorescence in situ hybridization (FISH) with probes for chromosomes 14 and 22 revealed 5.83% of chromosomally abnormal testicular spermatozoa. FISH with probes for chromosomes X, Y, and 21 showed frequencies of disomic and diploid testicular spermatozoa increased when compared to ejaculated sperm of healthy donors, but comparable with published results for azoospermic patients. PGD by FISH for the translocation and aneuploidy of chromosomes X, Y, 13, 18, and 21 showed a normal chromosomal complement in one out of three analyzed embryos. A healthy carrier girl was born after the embryo transfer. This study shows the benefits of preimplantation genetic diagnosis in a case of a rare Robertsonian translocation carrier with azoospermia and a relatively low frequency of chromosomally unbalanced testicular spermatozoa.


Asunto(s)
Aneuploidia , Azoospermia/genética , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 22 , Tamización de Portadores Genéticos , Meiosis/genética , Espermatozoides/metabolismo , Translocación Genética , Humanos , Cariotipificación , Masculino
3.
Horm Mol Biol Clin Investig ; 13(1): 1-5, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25436708

RESUMEN

The data on hormonal steroids in the human seminal plasma and their role in spermatogenesis are summarized. The seminal steroid levels need not correlate with the blood plasma levels. The recent reports showed that androgen, especially dihydrotestosterone, and the estrogen levels in the seminal fluid may be used as the markers of spermatogenesis impairment. The estradiol concentration in the seminal plasma was higher than in the blood plasma, and its levels were significantly increased in men with impaired spermatogenesis. A good indicator for predicting the normal spermatogenesis, therefore, seems to be the testosterone/estradiol ratio. The seminal plasma also contains significant amounts of cortisol, which influences the androgen biosynthesis through its receptors in the Leydig cells. The local balance between cortisol and inactive cortisone is regulated by 11ß-hydroxysteroid dehydrogenase, the activity of which may be affected by the environmental chemicals acting as the endocrine disruptors (EDCs). These compounds are believed to participate in worsening the semen quality - the sperm count, motility, and morphology, as witnessed in the recent last decades. As to the steroids' role in the testis, the EDCs may act as antiandrogens by inhibiting the enzymes of testosterone biosynthesis, as the agonists or antagonists through their interaction with the steroid hormone receptors, or at the hypothalamic-pituitary-gonadal axis. Surprisingly, though the EDCs affect the steroid action in the testis, there is no report of a direct association between the concentrations of steroids and the EDCs in the seminal fluid. Therefore, measuring the steroids in the semen, along with the various EDCs, could help us better understand the role of the EDCs in the male reproduction.


Asunto(s)
Disruptores Endocrinos/metabolismo , Semen/citología , Semen/metabolismo , Espermatogénesis , Esteroides/metabolismo , Animales , Humanos , Masculino , Reproducción , Semen/química , Esteroides/análisis
4.
Klin Mikrobiol Infekc Lek ; 18(5): 150-5, 2012 Oct.
Artículo en Checo | MEDLINE | ID: mdl-23208869

RESUMEN

This review article provides information on the impact of HIV-1 on male reproductive functions. HIV-positive patients of reproductive age with now a long-term prognosis may wish to have children. If only one partner is infected, natural conception brings the risk of virus transmission. The article reviews the reproduction possibilities for HIV-positive couples and explains the ways to reduce the risk of transmitting the virus to the healthy partner or a child. Assisted reproduction techniques, especially intrauterine insemination, in vitro fertilization and intracytoplasmic sperm injection in combination with sperm washing can successfully reduce the risk of HIV transmission. Current trends and dilemmas of infertility treatment in HIV-positive couples are discussed.


Asunto(s)
Infecciones por VIH/complicaciones , VIH-1 , Transmisión Vertical de Enfermedad Infecciosa , Infertilidad Masculina/etiología , Técnicas Reproductivas Asistidas , Femenino , Infecciones por VIH/transmisión , Humanos , Infertilidad Masculina/terapia , Masculino
5.
Cas Lek Cesk ; 151(8): 392-6, 2012.
Artículo en Checo | MEDLINE | ID: mdl-23101893

RESUMEN

BACKGROUND: The aim of the study was to evaluate prostate transrectal ultrasonography findings in men with congenital hypogonadism treated by long term testosterone replacement therapy. METHODS: We have gradually included 31 men with congenital hypogonadism in period of 2001-2011. The average follow-up was 7.3 years (2 months - 10.8 years). We have used Sustanon® 250 i.m. every 3 weeks or Nebido® i.m. every 3 months for continual testosterone replacement therapy. We performed to all patients the transrectal ultrasonography of prostate and seminal vesicles by biplanar rectal probe every 6 months. RESULTS: During the transrectal ultrasonography we observed in 22 (71.0 %) patients changes in prostatic tissue. In case of 12 patients were diagnosed asymptomatic prostatic cysts, in 9 patients prostatolithiasis and in 5 patients changes in echogenity of prostatic tissue. In 2 patients was found simultaneous occurrence of prostatic cyst and prostolithiasis, in further 2 patients simultaneous occurrence of hyperechogenic prostatic lesion and prostatolithiasis. The above described findings were diagnosed in 5 patients in the treatment lasting from 3 to 5 years, for the other 17 men with hormone replacement therapy longer than 5 years. CONCLUSIONS: The study presents long term results of complex treatment in patients with disorders of sexual development, onset and progress of puberty. The long term treatment of these patients in interdisciplinary cooperation of endocrinologist and andrologist may significantly contribute to clarify an impact of testosterone replacement therapy on prostate development.


Asunto(s)
Terapia de Reemplazo de Hormonas , Hipogonadismo/tratamiento farmacológico , Próstata/diagnóstico por imagen , Testosterona/uso terapéutico , Adolescente , Adulto , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Hipogonadismo/congénito , Masculino , Enfermedades de la Próstata/inducido químicamente , Enfermedades de la Próstata/diagnóstico por imagen , Testosterona/efectos adversos , Ultrasonografía , Adulto Joven
6.
Arch Gynecol Obstet ; 286(4): 1055-9, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22736041

RESUMEN

PURPOSE: To prevent multiple pregnancies the goal of ovulation induction by gonadotropins is to achieve only mono-follicular development. The most important issue is therefore to determine the starting dose. The aim of this study is to compare three different starting doses of follitropin beta to assess the lowest effective dose. METHODS: We evaluated 92 cycles with ovarian stimulation for patients with unexplained infertility, anovulatory disorder or mild male factor. We prospectively divided patients into 50, 75 and 100 IU groups based on patients' response to clomiphene citrate treatment. RESULTS: We performed 87 intrauterine inseminations (95 % of cycles with ovulation induction). Five cycles were cancelled. We achieved 15 pregnancies; total pregnancy rate was 18 %. Pregnancy rate was 22, 10 and 28 % in 50, 75 and 100 IU follitropin beta groups. The average number of follicles was 2.0 ± 0.8, 2.2 ± 1.1 and 2.5 ± 1.8 (ns), total dose of gonadotropins (IU) 483 ± 192, 600 ± 151 and 830 ± 268 (p < 0.001), respectively. We observed one case of twins in 75 and 100 IU treatment group, as well (25 % risk). CONCLUSIONS: This study suggests that based on the dose which was chosen according to clomiphene citrate response, all treatment regimes were effective for ovulation induction. 50 IU of follitropin beta daily is the appropriate starting dose to support ovulation for clomiphene citrate-sensitive women. The disadvantage may be an increased risk of cycle cancellation due to low ovarian response. Daily doses 75 or 100 IU of rFSH increase total consumption of gonadotropins.


Asunto(s)
Endometrio/efectos de los fármacos , Hormona Folículo Estimulante Humana/administración & dosificación , Folículo Ovárico/efectos de los fármacos , Inducción de la Ovulación/métodos , Índice de Embarazo , Adulto , Femenino , Humanos , Inseminación Artificial , Masculino , Síndrome de Hiperestimulación Ovárica/epidemiología , Embarazo , Embarazo Múltiple/estadística & datos numéricos , Estudios Prospectivos , Proteínas Recombinantes/administración & dosificación
7.
Cas Lek Cesk ; 149(1): 16-20, 2010.
Artículo en Checo | MEDLINE | ID: mdl-20662455

RESUMEN

Approximately 15% of men with newly diagnosed cancer are younger than 55 years, and about 26% of them are younger than 20 years. However the most common cause of fertility disorders is oncological treatment itself, the oncological diseases, changes in anatomy, and primary or secondary hormonal insufficiency are also significant factors. The chemotherapy, radiation, or their combination reduce sperm count, impair sperm motility and cause disorders in morphology and DNA integrity. Prognosis of sperm production recovery depends on the type of cancer, stage of the disease, patient age, drug treatment, treatment route and dosage, and pre-treatment male fertility.


Asunto(s)
Infertilidad Masculina/etiología , Neoplasias/terapia , Antineoplásicos/efectos adversos , Humanos , Masculino , Radioterapia/efectos adversos
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