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1.
Prog Urol ; 31(8-9): 458-476, 2021.
Artigo em Francês | MEDLINE | ID: mdl-34034926

RESUMO

OBJECTIVES: The Francophone Society of Sexual Medicine (SFMS) and the Andrology and Sexual Medicine Committee (CAMS) of the French Association of Urology (AFU) have brought together a panel of experts to develop French recommendations for the management of testosterone deficiency (TD). METHODS: Systematic review of the literature between 01/2000 and 07/2019. Use of the method of recommendations for clinical practice (RPC) and the AGREE II grid. RESULTS: TD is defined as the association of clinical signs and symptoms suggestive of TD with a decrease in testosterone levels or serum androgen activity. Diagnosis requires a T lower than the reference values in young men on 2 successive assays. Sexual disorders are often at the forefront, and concern the whole male sexual function (desire, arousal, pleasure and orgasm). The most evocative symptoms are: decrease in sexual desire, disappearance of nocturnal erections, fatigue, loss of muscle strength. Overweight, depressed mood, anxiety, irritability and malaise are also frequently found. TD is more common in cases of metabolic, cardiovascular, chronic, andrological diseases, and in cases of corticosteroid, opioid, antipsychotic, anticonvulsant, antiretroviral, or cancer treatment. Since SHBG is frequently abnormal, we recommend that free or bioavailable T is preferred over total T. The treatment of TD requires a prior clinical (DRE, breast examination) and biological (PSA, CBC) assessment. Contraindications to T treatment are: progressive prostate or breast cancer, severe heart failure or recent cardiovascular event, polycytemia, complicated BPH, paternity project. It is possible in cases of sleep apnea syndrome, psychiatric history, stable heart disease, prostate cancer under active surveillance and after one year of complete remission of a low or intermediate risk localized prostate cancer treated in a curative manner. It includes long-term testosterone supplementation and life-style counseling. Treatment is monitored at 3, 6, 12 months and annually thereafter. It is clinical (annual DRE) and biological (total T, PSA, CBC), the most frequent side effect being polyglobulia. CONCLUSION: These recommendations should help improve the management of TD.


Assuntos
Testosterona/deficiência , Testosterona/uso terapêutico , Algoritmos , Árvores de Decisões , Deficiências Nutricionais/diagnóstico , Deficiências Nutricionais/tratamento farmacológico , Humanos , Masculino
3.
Prog Urol ; 23(9): 621-8, 2013 Jul.
Artigo em Francês | MEDLINE | ID: mdl-23830256

RESUMO

INTRODUCTION: Relations between sexual desire and testosterone are more complex than previously thought particularly in ageing males. METHODS: A Medline search of the existing literature utilizing terms testosterone, libido, sexual desire, hypogonadism, and andropause, was performed until January 2012. RESULTS: Testosterone is a physiological stimulator of sexual desire. In case of complete hypogonadism, libido is very low and testosterone treatment restores sexual desire. In epidemiological studies, the relationship between testosterone and sexual desire is statistically significant but less strict because of interactions with other factors which decrease both sexual desire and testosterone levels. It is especially the case in ageing males: in addition to a possible late-onset hypogonadism, other etiological factors (health, partnership, socioeconomical and psychological factors) and other sexual dysfunctions (such as erectile dysfunction) must be taken into account. CONCLUSION: The decrease of sexual desire is one of the symptoms seen in late-onset hypogonadism. The effect of testosterone replacement therapy is more obvious that testosterone is low and there are no other causes of impaired sexual desire. There is no evidence that testosterone therapy increases the risk of prostate cancer, benign prostatic hyperplasia or promotes the clinical expression of subclinical prostate cancer.


Assuntos
Disfunções Sexuais Fisiológicas , Disfunções Sexuais Psicogênicas , Testosterona/deficiência , Fatores Etários , Humanos , Libido/fisiologia , Masculino , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Disfunções Sexuais Fisiológicas/epidemiologia , Disfunções Sexuais Fisiológicas/etiologia , Disfunções Sexuais Psicogênicas/tratamento farmacológico , Disfunções Sexuais Psicogênicas/epidemiologia , Disfunções Sexuais Psicogênicas/etiologia , Sexualidade/fisiologia , Testosterona/fisiologia , Testosterona/uso terapêutico
4.
Int J Androl ; 30(3): 153-62, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17239087

RESUMO

Patients with severe spermatogenesis impairment can now successfully father a child thanks to the use of intracytoplasmic sperm injection (ICSI). In oligozoospermic patients, many studies have reported significantly higher sperm aneuploidy rates and therefore an increased risk of transmitting a chromosomal abnormality via the injection of abnormal spermatozoa. However, the frequency of aneuploidy is highly variable between patients. The aim of the present work was to identify clinical and biological factors, which, together with non-obstructive oligozoospermia, could be predictive of elevated sperm aneuploidies. The sperm aneuploidy rates for chromosomes X, Y, 13, 18 and 21 were assessed in 31 infertile men with well-characterized spermatogenesis impairment, and in a population of control men with proven fertility. The frequency of sperm aneuploidy was compared between several patient subgroups according to their clinical and biological factors. Nearly half of the oligozoospermic males (15/31) had a significantly increased disomy rate for at least one of the five chromosomes compared with that observed in the control population (mean disomy rates + 1.96 standard deviation). Factors significantly associated with higher numbers of aneuploid sperm were cigarette smoking, an elevated follicle-stimulating hormone level, a sperm concentration less than 1 m/mL, and a severe teratozoospermia. Hence, several factors predictive of an increased risk of sperm aneuploidy rates were identified in ICSI male candidates with a non-obstructive oligozoospermia.


Assuntos
Aneuploidia , Astenozoospermia/fisiopatologia , Oligospermia/fisiopatologia , Espermatozoides/anormalidades , Adulto , Astenozoospermia/genética , Anormalidades Congênitas/genética , Hormônio Foliculoestimulante/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Oligospermia/genética , Valor Preditivo dos Testes , Fumar , Contagem de Espermatozoides , Espermatogênese
5.
Ann Endocrinol (Paris) ; 64(2): 117-25, 2003 Apr.
Artigo em Francês | MEDLINE | ID: mdl-12773947

RESUMO

With age, some men develop symptoms resembling hypogonadism. Several cross-sectional and longitudinal studies have shown a decrease in testosterone levels with ageing in men. This finding has equally been observed in elderly men in good health. Testosterone levels decline progressively as of the thirties, at a rate which remains constant throughout life. While total testosterone levels decrease, sex hormone binding globulin (SHBG) levels on the contrary increase with age, with the result that the levels of free and non-SHBG-bound testosterone (corresponding to the fraction which is bioavailable to target cells) decrease more abruptly than that of total testosterone. Higher LH levels, decreased testosterone response to hCG and less Leydig cells all indicate that ageing induces partial testicular failure. However, the gonadotropic function is also affected in ageing. The hypothalamus-pituitary becomes more sensitive to gonad steroid feedback, LH pulse amplitude decreases, and the LH response to GnRH is blunted compared to the situation in young men. Thus LH level is not a valid index of androgen deficiency in elderly males. None of the androgen-dependent functions (libido, erection, sense of well-being, muscle mass and strength, fat mass, bone mass, erythropoiesis, etc.) are under exclusively androgen control, and there is no elderly male symptom which is completely specific to androgen deficiency. Thus, in elderly men, when clinical symptoms might indicate androgen deficiency, biological confirmation is needed. An assay which is independent of SHBG fluctuations is mandatory. Bioavailable testosterone assay by ammonium sulfate precipitation seems to us to be the optimum method for diagnosing androgen deficiency: it gives a reliable measurement for the testosterone fraction available to target cells, is adapted to clinical practice, and provides results that can be directly compared with current reference values for healthy young men.


Assuntos
Envelhecimento , Androgênios/deficiência , Testosterona/sangue , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Globulina de Ligação a Hormônio Sexual/análise , Globulina de Ligação a Hormônio Sexual/metabolismo , Testículo/fisiologia
6.
Hum Reprod ; 16(10): 2093-7, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11574497

RESUMO

BACKGROUND: Most infertile males with congenital bilateral absence of vas deferens (CBAVD) carry mutations on the cystic fibrosis transmembrane conductance regulator gene and may express mild cystic fibrosis (CF) symptoms. Barriers to paternity for these men can now be overcome by assisted reproduction. Our aims were to investigate the CF-related phenotype and clinical outcome for 50 patients with CBAVD seen at a CF adult centre between 1992 and 1999. METHODS AND RESULTS: The investigation of the patients included screening for 22 CF mutations and identification of the poly-T variant of intron 8, sweat testing, clinical investigation for CF-related extra-genital manifestations, and genetic counselling. CFTR mutations were detected on 56 alleles of the 50 patients. A total of 15 (30%) was compound heterozygote and 26 (52%) heterozygote. In all, 38% of the patients had a positive sweat test. Four patients were diagnosed with typical CF not detected previously. Twenty-one patients became fathers following ICSI (eight cases), artificial insemination by donor or IVF with sperm donor (seven cases) or through adoption (six cases). A mail survey allowed the identification of CF-related clinical symptoms. Information on the occurrence of CF-related symptoms was obtained for 58.5% of patients: in the absence of initial symptoms, no new clinical signs were reported. CONCLUSION: Patients diagnosed with CBAVD need genetic counselling before assisted reproduction. Even when no wish for paternity is expressed, CF gene screening should be associated with at least a sweat test and clinical evaluation because of possible mild forms of CF disease. Medical follow-up did not reveal any new symptoms.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Resultado da Gravidez , Ducto Deferente/anormalidades , Adulto , Estudos de Coortes , Análise Mutacional de DNA , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Fenótipo , Gravidez , Estudos Retrospectivos
7.
J Steroid Biochem Mol Biol ; 70(4-6): 115-21, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10622399

RESUMO

Human sex hormone-binding globulin (hSHBG) is a plasma glycoprotein that binds sex steroids with high affinity. Variations in hSHBG glycosylation contribute to its electrophoretic microheterogeneity, but the functional significance of different SHBG glycoforms is unknown. Carbohydrates may influence the biological activities and half-lives of glycoproteins and we have examined how oligosaccharides at specific sites influence the plasma clearance of hSHBG in vivo. To accomplish this, fully-glycosylated hSHBG, or hSHBG mutants lacking specific oligosaccharides chains, were expressed in Chinese hamster ovary (CHO) cells and purified by immunoaffinity chromatography. The purified recombinant proteins were then biotinylated to study their plasma half-lives after intravenous injection into rabbits. When compared to hSHBG isolated from serum, recombinant hSHBG migrates with a slightly larger average molecular size during denaturing polyacrylamide gel electrophoresis. This is due to a greater proportion (33-39% vs. 3%) of more highly branched N-linked oligosaccharides on the recombinant proteins. When injected into rabbits, the disappearance of recombinant hSHBG showed two exponential components, as previously shown for natural hSHBG in the same animal model. The mean +/- S.E.M. plasma half-lives of recombinant hSHBG (t 1/2alpha 0.11+/-0.03 h and t 1/2beta 18.94+/-1.65 h) are shorter than previously measured for natural hSHBG (t 1/2alpha 3.43+/-0.72 h and t 1/2beta 38.18+/-7.22 h) and this is likely due to differences in the composition of their N-linked oligosaccharides. An O-linked chain at Thr7 does not influence the plasma clearance of hSHBG in the presence or absence of N-linked carbohydrates at Asn351 and Asn367. However, a 1.5-1.6 fold (p<0.03) increase in plasma half-life of variants lacking both N-glycosylation sites was observed and this is probably due to the fact these variants are not recognized by the asialoglycoprotein receptor-mediated clearance system. Removal of either N-glycosylation consensus site also increased (p<0.0001) the plasma half-life of hSHBG by 2.3 2.4 fold. Thus, the metabolic clearance of hSHBG appears to be determined by the number of N-linked oligosaccharides rather than their location.


Assuntos
Globulina de Ligação a Hormônio Sexual/farmacocinética , Animais , Biotinilação , Células CHO , Cromatografia de Afinidade , Cricetinae , Glicosilação , Meia-Vida , Humanos , Ensaio Imunorradiométrico , Masculino , Taxa de Depuração Metabólica , Coelhos , Proteínas Recombinantes/sangue , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/farmacocinética , Globulina de Ligação a Hormônio Sexual/genética , Globulina de Ligação a Hormônio Sexual/isolamento & purificação , Transfecção
8.
Mol Cell Endocrinol ; 144(1-2): 59-69, 1998 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-9863627

RESUMO

Since recombinant hormones are considered as safer and more reliable in their bioactivity than extractive hormones, the recently available human recombinant luteinizing hormone (r-hLH), will probably replace hCG in the near future, for clinical purposes. This prompted us to investigate whether or not, and by which mechanisms, r-hLH can induce a desensitization of signal transduction and/or an up-regulation of steroidogenic capacity in Leydig cells. The effects of a 30 min to 24 h exposure to r-hLH (10(-9) M) on the differentiated functions of cultured immature porcine Leydig cells were studied by measuring the following parameters: LH/hCG receptor number and mRNA, hCG-, cholera toxin- and forskolin-induced cAMP production, G protein alphas subunit content of the membrane, hCG-, cholera toxin-, forskolin-, 8Br-cAMP-, 22R-OH-cholesterol-, progesterone-, 170H-progesterone-, DHEA-, delta4-androstenedione-induced testosterone secretion and StAR, 3beta-HSD, cytochrome P-450scc and P-450c17 mRNAs. hCG binding sites and LH/hCG receptor mRNA were slowly down regulated by r-hLH, reaching 47+/-1 and 18+/-7% of control at 24 h, respectively. Down-regulation of both hCG- and cholera toxin-induced cAMP production occurred earlier and was more marked, and at 24 h represented only 2.7+/-0.5 and 12.5+/-3.6% of control. Due to the synergistic effect of r-hLH and forskolin on cAMP production, the forskolin-induced cAMP was higher in r-hLH treated than in control cells, but this response also declines with time and was, at 24 h, only 32% of that observed at 30 min. This decreased cAMP production was associated with a less marked decline in the amount of membrane content of Galphas protein. The testosterone production in response to hCG, cholera toxin, forskolin and 8Br-cAMP declined to reach a nadir at 6 h but increased thereafter and at 24 h was significantly higher than in control cells. In contrast, the conversion of several precursors into testosterone remained stable or increased slightly during the first hours of r-hLH treatment and significantly increased at 24 h and this was associated with an increase of StAR, 3beta-HSD, P-450scc and P-450c17 mRNAs. Taken together, the present results indicate that, despite the marked down-regulation of transmembrane signaling, r-hLH increased the steroidogenic capacity of Leydig cells by increasing the expression of several genes encoding the proteins involved in testosterone synthesis.


Assuntos
Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Animais , Toxina da Cólera/farmacologia , Gonadotropina Coriônica/metabolismo , Gonadotropina Coriônica/farmacologia , Colforsina/farmacologia , AMP Cíclico/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/agonistas , Subunidades alfa Gs de Proteínas de Ligação ao GTP/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Hidroxiesteroide Desidrogenases/genética , Cinética , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/metabolismo , Masculino , Fosfoproteínas/genética , RNA Mensageiro/análise , Receptores do LH/genética , Receptores do LH/metabolismo , Proteínas Recombinantes/farmacologia , Suínos , Testosterona/metabolismo
9.
J Clin Endocrinol Metab ; 82(11): 3758-62, 1997 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9360537

RESUMO

Plasma corticosteroid-binding globulin (CBG) concentrations decrease dramatically in patients with septic shock or burn injury. This decrease suggests that mediators of the acute phase response, such as cytokines and glucocorticoid hormones, might influence clearance as well as liver synthesis of CBG in humans. The present study investigated the effects of interleukin-6 (IL-6), IL-1 beta, and dexamethasone on CBG synthesis by a clone of human hepatoblastoma-derived (HepG2) cell line. In culture medium from HepG2 cells, the immunoconcentration of CBG and the levels of CBG messenger ribonucleic acid (mRNA) were dose dependently decreased in the presence of IL-6 concentrations ranging from 0.1-10 ng/mL. The percent decrease in CBG immunoconcentration was quantitatively similar to the percent decrease in CBG mRNA levels (29 +/- 6% and 39 +/- 15%, respectively, of control values). In contrast, and as expected, IL-6 dose dependently increased the mRNA levels (164 +/- 22% of control values) of alpha 1-antitrypsin, a positive acute phase protein, but did not affect the immunoconcentration of sex hormone-binding globulin, another liver protein. Dexamethasone alone did not significantly affect CBG secretion or mRNA levels, but did dose-dependently increase tyrosine amino-transferase mRNA levels, which increased to 252 +/- 16% of the control values. However, in combination with IL-6, dexamethasone had a significant additive effect on IL-6 inhibition of CBG secretion and mRNAs in HepG2 cells. IL-1 beta dose-dependently stimulated CBG secretion (156 +/- 10% of control values) with no significant effect on CBG mRNA levels. In addition, IL-1 beta significantly decreased the inhibitory effect of IL-6 on CBG secretion, but had no effect on the inhibitory effect of IL-6 on CBG mRNA levels. These results suggest that IL-1 beta acts on the posttranslation processing and/or secretion mechanisms of CBG in HepG2 cells. Together, the present results strongly support the hypothesis that the decrease in plasma CBG concentrations is associated with the increase in IL-6 and glucocorticoid levels reported in patients with septic shock and burn injury.


Assuntos
Citocinas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Glucocorticoides/farmacologia , Hepatoblastoma/metabolismo , Neoplasias Hepáticas/metabolismo , Transcortina/genética , Meios de Cultivo Condicionados , Dexametasona/farmacologia , Interações Medicamentosas , Humanos , Interleucina-1/farmacologia , Interleucina-6/farmacologia , RNA Mensageiro , Células Tumorais Cultivadas
10.
J Clin Endocrinol Metab ; 82(5): 1426-33, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9141528

RESUMO

Interleukins (IL)-1 and -6 have been shown to be produced by several categories of cells in the rat testis and involved in the paracrine control of testicular function. Evidence of high amounts of IL-1 have been shown in the human testis, but nothing is known about its cellular origin. Furthermore, to our knowledge, the presence of IL-6 in the human testis has not yet been investigated. Therefore, the present study was aimed at identifying IL-1 and -6 expression and production within the human testis, using RT-PCR, bioassays, and enzyme linked immunosorbent assays. We demonstrated that IL-1 and -6 messenger RNA and proteins were produced constitutively in vitro by human Leydig cell- and Sertoli cell-enriched preparations. FSH only stimulated IL-6 production by Sertoli cell-enriched preparations, but increased the release of both IL-1 and -6 in germ cell-depleted Sertoli cell cultures. In addition, lipopolysaccharides and latex beads enhanced the production of both cytokines by Sertoli cell cultures, whereas human chorionic gonadotropin and lipopolysaccharides enhanced the release of both cytokines by Leydig cells. Enzyme linked immunosorbent assays and neutralization experiments revealed that human Sertoli cells produce essentially the alpha form of IL-1, whereas both forms, alpha and beta, are present in Leydig cells. The demonstration that human Leydig and Sertoli cells produce IL-1 and -6 under the control of gonadotropin hormones and exogenous factors, opens the possibility to study the involvement of these cytokines in the control of testis function, in normal and pathological conditions in men.


Assuntos
Interleucina-1/biossíntese , Interleucina-6/biossíntese , Células Intersticiais do Testículo/metabolismo , Células de Sertoli/metabolismo , Adulto , Células Cultivadas , Gonadotropina Coriônica/farmacologia , Meios de Cultura , Ensaio de Imunoadsorção Enzimática , Hormônio Foliculoestimulante/farmacologia , Humanos , Látex , Células Intersticiais do Testículo/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Masculino , Microesferas , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese , Células de Sertoli/efeitos dos fármacos
11.
Biol Reprod ; 55(1): 99-110, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8793064

RESUMO

In human spermatogenic cells, in contrast to somatic cells, expression of major histocompatibility complex (MHC) class I molecules is undetectable. This lack of expression may contribute to the absence of female immune reaction against spermatozoa and may be necessary for gamete fusion. Among the molecular repressor mechanisms that may be used at the DNA level, we investigated 5' CpG methylation of the different class Ia and class Ib loci in meiotic pachytene spermatocytes and postmeiotic round spermatids, which had been purified from human testes by centrifugal elutriation. These results were compared with those obtained with mature spermatozoa and peripheral blood mononuclear cells. Using methylation-sensitive restriction enzymes and DNA locus-specific probes, we found that HLA-A, HLA-B/C, and HLA-E loci were similarly unmethylated in the germ and somatic cells tested, whereas HLA-F and HLA-G were even less methylated in the former cells. Together with the observation that spermatozoon DNA contains class I genes that are transfectable and able to direct transcription and protein synthesis in murine L cells, these data suggest that HLA class I genes are in an active conformation in male germ cells. We indeed found that both spermatocytes and spermatids contained low levels of class Ia and class Ib mRNA. Using reverse transcriptase-polymerase chain reaction, followed by DNA sequencing, we also detected three HLA-G transcriptional isoforms, resulting from alternative splicings, which suggested that this class Ib gene may have a potential function in these germ cells. Although intracellular expression of beta2-microglobulin (the light chain that associates with HLA class I heavy chains) was found in spermatocytes but not in round spermatids, no membrane-bound nor intracellular translated HLA class I heavy chain was detected in either germ cell type, when monomorphic anti-HLA class I monoclonal antibodies were used. Thus, lack of expression of HLA class I proteins in the male germ line is likely to involve post-transcriptional mechanisms of regulation.


Assuntos
Expressão Gênica , Genes MHC Classe I/genética , Meiose , Espermatozoides/imunologia , Processamento Alternativo , Animais , Sequência de Bases , Metilação de DNA , Feminino , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Conformação de Ácido Nucleico , RNA Mensageiro/análise , Espermátides/imunologia , Espermatogênese , Transfecção , Células Tumorais Cultivadas
12.
J La State Med Soc ; 147(10): 444-7, 1995 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8558049

RESUMO

One in three adults in the United States smokes. Smokers inhale one quarter of the smoke from cigarettes. But 75% of cigarette smoke is released into the environment. Nonsmokers are exposed to this environmental tobacco smoke and are at risk for disease. A growing body of literature supports the association of passive, involuntary, or secondhand smoking with human pathology. This discussion examines the makeup of environmental tobacco smoke and its role in causing human disease with a review of the literature relating environmental tobacco smoke to head and neck pathology.


Assuntos
Otorrinolaringopatias/etiologia , Poluição por Fumaça de Tabaco/efeitos adversos , Adolescente , Adulto , Criança , Pré-Escolar , Ensaios Clínicos como Assunto , Tosse/epidemiologia , Tosse/etiologia , Feminino , Humanos , Incidência , Masculino , Otite Média com Derrame/epidemiologia , Otite Média com Derrame/etiologia , Otorrinolaringopatias/epidemiologia , Fatores de Risco , Ronco/epidemiologia , Ronco/etiologia , Tonsilite/epidemiologia , Tonsilite/etiologia
13.
J Clin Endocrinol Metab ; 80(7): 2057-62, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7608255

RESUMO

Evidence suggests that hyperinsulinemic insulin resistance may increase serum levels of ovarian androgens and reduce sex hormone-binding globulin (SHBG) levels in humans. The present study was conducted to assess the effect of administration of the biguanide metformin, a drug commonly used in the treatment of diabetes mellitus, on androgen and insulin levels in 24 hirsute patients. The patients selected for the study were obese, with a body mass index higher than 25 kg/m2 and high fasting insulin (> 90 pmol/L) and low SHBG levels (< 30 nmol/L). All patients were given a low calorie diet (1500 Cal/day) and randomized for either metformin administration at a dose of 850 mg or a placebo, twice daily for 4 months, in a double blind study. In the placebo group, diet resulted in a significant decrease in body mass index (30.8 +/- 1.0 vs. 32.7 +/- 1.5 kg/m2; P < 0.0001), fasting insulin (127 +/- 11 vs. 156 +/- 14 pmol/L; P < 0.01), non-SHBG-bound testosterone (0.19 +/- 0.02 vs. 0.28 +/- 0.03 nmol/L; P < 0.02), androstenedione (5.8 +/- 0.5 vs. 9.0 +/- 1.1 nmol/L; P < 0.03), and 3 alpha-diolglucuronide (8.6 +/- 1.1 vs. 11.7 +/- 1.9; P < 0.005) plasma concentrations and a significant increase in the glucose/insulin ratio (0.047 +/- 0.005 vs. 0.035 +/- 0.003; P < 0.001) and plasma concentrations of SHBG (26.0 +/- 3.3 vs. 19.1 +/- 1.9 nmol/L; P < 0.001) and dehydroepiandrosterone sulfate (8.7 +/- 1.5 vs. 8.4 +/- 1.3; P < 0.05). Beneficial effects of diet were not significantly different in the patients who were given metformin instead of placebo. These results confirm that weight loss induced by a low calorie diet is effective in improving hyperinsulinemia and hyperandrogenism in obese and hirsute women. With our study design, metformin administration had no additional benefit over the effect of diet.


Assuntos
Androgênios/metabolismo , Dieta com Restrição de Gorduras , Dieta Redutora , Hirsutismo/fisiopatologia , Insulina/metabolismo , Metformina/uso terapêutico , Obesidade/fisiopatologia , Globulina de Ligação a Hormônio Sexual/análise , Androgênios/sangue , Apolipoproteína A-I/sangue , Apolipoproteínas B/sangue , Glicemia/metabolismo , Composição Corporal , Colesterol/sangue , HDL-Colesterol/sangue , Desidroepiandrosterona/análogos & derivados , Desidroepiandrosterona/sangue , Sulfato de Desidroepiandrosterona , Feminino , Hirsutismo/dietoterapia , Hirsutismo/tratamento farmacológico , Humanos , Insulina/sangue , Secreção de Insulina , Obesidade/dietoterapia , Obesidade/tratamento farmacológico , Placebos , Triglicerídeos/sangue
14.
J Steroid Biochem Mol Biol ; 53(1-6): 567-72, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7626511

RESUMO

The incidence of coronary artery disease is significantly higher in men than in women, at least until menopause. This gender difference could be explained by the action of sex steroids on the lipoprotein profile. In prepubertal children, high-density lipoprotein (HDL) cholesterol and triglyceride levels are similar between sexes, while adult men have generally lower HDL cholesterol and higher triglyceride levels than premenopausal adult women. Most cross-sectional studies have reported that sex hormone binding globulin (SHBG) and testosterone levels correlate positively with HDL cholesterol levels between sexes. Thus SHBG by modulating the balance in the biodisposal of testosterone and estradiol, might have a profound effect on the risk of cardiovascular disease. However, adjustment for body weight and body fat distribution weakens the association between SHBG, testosterone and HDL cholesterol. The negative correlation of fasting insulin with SHBG and HDL cholesterol levels in both sexes, and some evidence that insulin is an inhibitor of SHBG production in vitro, has suggested that hyperinsulinism might negatively regulate SHBG and HDL levels. It remains to be determined whether the inverse relationship between SHBG and insulin levels is coincidental or has a causal effect on the increase of atherosclerosis. Decreased SHBG has been shown to be predictive of the incidence of non-insulin-dependent diabetes mellitus in women but not in men, and of subsequent development of cardiovascular disease and overall mortality in postmenopausal women. SHBG is an index of androgenism in women and of insulin-resistance in both sexes, and might be useful in epidemiological studies of cardiovascular risk. However, in men, SHBG is not predictive of the occurrence of cardiovascular disease. Whether SHBG might have an intrinsic protective effect on the arterial wall through SHBG-receptors is still highly speculative.


Assuntos
Doenças Cardiovasculares/etiologia , Lipoproteínas/sangue , Globulina de Ligação a Hormônio Sexual/metabolismo , Adulto , Consumo de Bebidas Alcoólicas , Dieta , Estrogênios/metabolismo , Exercício Físico , Feminino , Humanos , Hidrocortisona/metabolismo , Resistência à Insulina , Masculino , Progesterona/metabolismo , Fatores de Risco , Fumar , Hormônios Tireóideos/metabolismo
15.
J Clin Endocrinol Metab ; 80(4): 1283-9, 1995 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-7536204

RESUMO

Changes in the plasma levels of corticosteroid-binding globulin (CBG) and sex hormone-binding globulin (SHBG) from birth to adulthood suggest that growth factors might influence clearance and/or hepatic secretion of CBG and SHBG in humans. The effects of insulin-like growth factor I (IGF-I) and insulin on CBG and SHBG synthesis by a clone of human hepatoblastoma-derived (Hep G2) cell lines were therefore investigated. The results showed that the immunoconcentrations of CBG and SHBG, as well as total protein concentration in culture medium from Hep G2 cells, were decreased by IGF-I and insulin. However, although the CBG-to-total protein ratio was decreased dose dependently by IGF-I and insulin, IGF-I and insulin did not dose-dependently decrease the SHBG-to-total protein ratio. The steady state levels of CBG and SHBG messenger RNAs (mRNAs) were reduced dose dependently by IGF-I with a half-effect at 5.4 +/- 1.9 and 4.6 +/- 1.6 nmol/L, respectively, and by insulin with a half-effect at 4.3 +/- 1.1 and 4.3 +/- 1.4 nmol/L, respectively. The maximum inhibitory effect of IGF-I on CBG mRNA level was 48 +/- 17% of control values and 60 +/- 13% for SHBG mRNA level. The changes in CBG mRNA levels were quantitatively similar to the changes in CBG immunoconcentration in the Hep G2 medium. In contrast, the inhibitory effects of insulin were only 17 +/- 8% and 31 +/- 12% of control values on CBG and SHBG mRNAs and 37 +/- 4% and 43 +/- 4% on CBG and SHBG concentrations, respectively. These results demonstrate that IGF-I reduces CBG and SHBG production by Hep G2 cells by decreasing mRNA steady state levels. The discrepancy between the inhibitory effects of insulin on CBG and SHBG mRNAs and protein secretion suggests that insulin exercises its inhibitory effects mainly on the mechanism(s) of translation and/or excretion of CBG and SHBG. The respective effects of IGF-I and insulin in the regulation of CBG and SHBG levels during fetal life and pubertal development in humans merit further study.


Assuntos
Hepatoblastoma/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Insulina/farmacologia , Neoplasias Hepáticas/metabolismo , Globulina de Ligação a Hormônio Sexual/metabolismo , Transcortina/metabolismo , Proteínas de Transporte/metabolismo , Estradiol/farmacologia , Hepatoblastoma/patologia , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina , Neoplasias Hepáticas/patologia , Somatomedinas/metabolismo , Tiroxina/farmacologia , Células Tumorais Cultivadas
16.
J La State Med Soc ; 147(2): 55-8, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7897288

RESUMO

The otolaryngologist seeking a cure of the patient with advanced cancer of the head and neck removes all neck metastases along with the primary tumor. Tumor involvement of the carotid artery presents a special dilemma to the otolaryngologist because a complete resection would mean removal of the affected carotid artery, a procedure which has, historically, carried high morbidity and mortality rates. Today, the otolaryngologist will offer tumor resection with carotid artery sacrifice only after a patient passes a preoperative assessment of collateral circulation to the brain. Numerous methods have been devised to determine a patient's preoperative risk of neurologic compromise. Several tests are detailed and their usefulness discussed.


Assuntos
Artéria Carótida Primitiva/fisiologia , Artéria Carótida Primitiva/cirurgia , Artéria Carótida Interna/fisiologia , Artéria Carótida Interna/cirurgia , Circulação Cerebrovascular/fisiologia , Circulação Colateral/fisiologia , Neoplasias de Cabeça e Pescoço/cirurgia , Cateterismo , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/fisiopatologia , Humanos , Metástase Linfática/patologia , Compostos de Organotecnécio , Oximas , Tecnécio Tc 99m Exametazima , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana , Xenônio
17.
Medicine (Baltimore) ; 74(1): 42-7, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7837969

RESUMO

The high frequency of cystic fibrosis (CF) mutations in males with absence of vas deferens supported the hypothesis of a primarily genital phenotype of CF disease. To consider the idea of an attenuated form of CF, we investigated 14 men with congenital bilateral aplasia of the vasa deferentia. All patients were consulting for infertility and none was known to have CF. The median age was 30.5 years (range, 20-38 yr). DNA analysis for 22 CF mutations showed at least 1 mutation in 10 patients (71%), whereas the CF carrier frequency is only 4% in the general population. Three compound heterozygotes were identified, all carriers of the R117H mutation. The sweat test was considered positive in 6 patients (43%), and a high frequency of radiologic evidence of sinus disease (8 patients) and of elevated antibodies to Pseudomonas (8 patients) was found. Only 2 patients were free of all these criteria for CF disease. This study strengthens the hypothesis that absence of vas deferens is an attenuated form of CF. We propose a combination of tests including DNA study, computerized tomographic scan of the paranasal sinuses, and testing of anti-Pseudomonas antibodies when the sweat test is inconclusive.


Assuntos
Fibrose Cística/diagnóstico , Ducto Deferente/anormalidades , Adulto , Cloretos/análise , Fibrose Cística/complicações , Fibrose Cística/genética , Triagem de Portadores Genéticos , Genótipo , Humanos , Infertilidade Masculina/complicações , Masculino , Suor/química
20.
Fertil Steril ; 57(4): 871-6, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1555701

RESUMO

OBJECTIVE: To investigate different factors involved in the outcome of in vitro fertilization (IVF) with epididymal spermatozoa in cases of vas deferens agenesis, with particular emphasis on sperm movement parameters. DESIGN: Prospective study in which sperm movement characteristics, level of puncture, and sperm preparation technique were studied relative to the outcome of IVF. SETTING: Département de Gynécologie, Oncologie Gynécologique, Sénologie, Médecine de la Reproduction, Hôpital Edouard-Herriot, Lyon France. PATIENTS: Thirteen couples underwent 15 IVF cycles. In 14 cycles (12 patients) epididymal spermatozoa could be recovered by surgical punctures. Epididymides were taken from 10 subjects in state of cerebral death to study epididymal spermatozoa under physiological status of the epididymis. RESULTS: The cleavage rate in IVF was low (25/158: 15.8%). In seven cases, embryo transfer was possible, leading to two twin pregnancies (4 infants born). Fertilization could be achieved with spermatozoa from the epididymis caput. Motility was paradoxically higher in the proximal epididymis than in the distal epididymis. In healthy epididymides, spermatozoa collected from the caput did not exhibit any progressive motility, whereas progressive motility was always present in the epididymis corpus. CONCLUSIONS: Our study showed that forward motility could be observed in the epididymis caput in patients with congenital absence of the vas deferens and that fertilization and ongoing pregnancies could be obtained from caput spermatozoa. On the other hand, in physiological status of the epididymis, forward motility was observed only as from the corpus area, confirming observations in other species.


Assuntos
Fertilização in vitro , Oligospermia/fisiopatologia , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Adulto , Epididimo , Feminino , Humanos , Masculino , Gravidez , Resultado da Gravidez , Estudos Prospectivos , Valores de Referência , Espermatozoides/patologia , Ducto Deferente/anormalidades
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