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1.
Rev Neurol (Paris) ; 176(3): 166-169, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31932031

RESUMO

Pathophysiology of amyotrophic lateral sclerosis (ALS) remains partially understood even though it is accepted worldwide that motor neuron death results from a pluri-factorial process with a variable role of genetic factors. Although not distinguishable from a clinical point of view, familial forms of ALS (fALS, 10% of cases) and sporadic forms (sALS, 90% of cases) can be described. Since the identification of superoxide dismutase 1 gene (SOD1) mutations, more than 30 genes have been linked to fALS. Among these genes, five (C9ORF72, SOD1, TARDBP, FUS, TBK1) seem predominant with mutation frequencies of 40%, 20%, 5%, <5%, <5% in fALS and 6%, 3%, and <1% for the last three in sALS, respectively. The situation that classically leads to request genetic screening is the presence of a familial history of motor neuron disorders (MND) or fronto-temporal lobar dementia (FTLD). However, this dichotomy between fALS and sALS based on familial history can lead to mistakes since illegitimacy, ignorance of MND, FTD or psychiatric disorders within the family due to a familial censorship or lack of familial relationship, or a recessive autosomal inheritance could wrongly lead to failing to recognize a familial form. The significant development of genetic research and easier access to genetic tests in fALS increase the number of situations for which gene mutations are identified. The consequence is an increase in genetic requests from relatives of ALS patients who are eager to know their own genetic status and their own individual risk to develop ALS. Pre-symptomatic testing is thus becoming a daily issue in ALS Centers. This led us to propose a framework for such pre-symptomatic genetic testing for people at risk for developing ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Esclerose Lateral Amiotrófica/genética , Testes Genéticos/normas , Esclerose Lateral Amiotrófica/epidemiologia , Doenças Assintomáticas , Confidencialidade/normas , Análise Mutacional de DNA/métodos , Análise Mutacional de DNA/normas , Revelação/normas , Diagnóstico Precoce , Frequência do Gene , Estudos de Associação Genética , Aconselhamento Genético/métodos , Aconselhamento Genético/normas , Predisposição Genética para Doença , Testes Genéticos/métodos , Humanos , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Diagnóstico Molecular/normas , Sintomas Prodrômicos
2.
AJNR Am J Neuroradiol ; 39(9): 1657-1661, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30115677

RESUMO

Adult-onset leukoencephalopathy with axonal spheroids and pigmented glia is an autosomal dominant leukoencephalopathy related to CSF1R gene mutations. A growing number of clinicoradiologic phenotypes have been described. In this study, we analyzed brain imaging findings in 16 patients with adult-onset leukoencephalopathy with axonal spheroids and pigmented glia to refine radiologic diagnostic clues. T2/FLAIR white matter hyperintensities were present in all patients with frontal or frontoparietal predilection, with asymmetric distribution in more than one-third. Brain atrophy and callosal involvement were almost constant, and corticospinal tract involvement was frequent. Moreover, deep white matter hyperintense dots on DWI and deep punctate calcifications on CT were often found. Conversely, deep gray matter nuclei, external capsules, and brain stem were rarely involved. Our series emphasized the great variability of MR imaging findings seen in adult-onset leukoencephalopathy with axonal spheroids and pigmented glia. A complete imaging screening including DWI, T2*, and CT is mandatory to accurately assess patients with suspected inherited adult-onset leukoencephalopathy.


Assuntos
Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/patologia , Adulto , Feminino , França , Humanos , Leucoencefalopatias/genética , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Neuroimagem/métodos
4.
J Neurol ; 262(4): 988-91, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25683759

RESUMO

Etiologic diagnosis of adulthood leukodystrophy is challenging in neurologic practice. We describe here the clinico-radiological features of a novel autosomal dominant leukodystrophy in a single family. Clinical and MRI features were recorded in a three generation family. Exome sequencing was performed in two affected relatives and one healthy member. Four total relatives (3 women and 1 man, mean age at onset: 45, range 32-59) were followed: 2 for migraine and 2 for cognitive loss. MRI features were homogeneous in the four affected relatives: extensive and symmetrical white matter hyperintensities on T2-weighted images, with a posterior predominance, involvement of the middle cerebellar peduncles, corpus callosum and the posterior limb of the internal capsules. An extensive metabolic screening was negative. In addition, sequencing of pathogenic genes involved in dominant leukodystrophies (NOTCH3, LMNB1, GFAP, CSF1R) was negative. No mutation has been identified yet with exome sequencing. This report is peculiar because of dominant inheritance, adult onset, highly homogeneous white matter hyperintensities on T2-weighted MR images, predominant in the middle cerebellar peduncles and posterior part of internal capsule and absence of mutation of the genes involved in dominant leukodystrophies.


Assuntos
Encéfalo/patologia , Leucoencefalopatias/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Exoma , Saúde da Família , Feminino , Testes Genéticos , Proteína Glial Fibrilar Ácida/genética , Humanos , Lamina Tipo B/genética , Leucoencefalopatias/líquido cefalorraquidiano , Leucoencefalopatias/genética , Masculino , Pessoa de Meia-Idade , Mutação , Receptor Notch3 , Receptores Notch/genética
5.
Andrologia ; 46(6): 703-6, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23808476

RESUMO

We report on a case of a man with familial, X-linked, partial androgen insensitivity, in whom a new point mutation in the androgen receptor (AR) ligand-binding domain (causing a valine-to-alanine substitution at codon 686) was identified. High-dose prolonged testosterone therapy resulted in marked progression in patient's appearance and great improvement in sperm count and characteristics. In combination with intracytoplasmic microinjection, treatment resulted in fertility. This is believed to be the first report of such a case. This case supports high-dose testosterone therapeutic trial in this condition. Furthermore, it underscores the possibility of achieving fertility with current endocrine and assisted reproduction modalities, making some of these X-linked AR mutations paternally transmissible.


Assuntos
Síndrome de Resistência a Andrógenos/tratamento farmacológico , Síndrome de Resistência a Andrógenos/genética , Mutação Puntual , Receptores Androgênicos/genética , Testosterona/uso terapêutico , Adulto , Substituição de Aminoácidos , Síndrome de Resistência a Andrógenos/patologia , Feminino , Humanos , Recém-Nascido , Infertilidade Masculina/genética , Infertilidade Masculina/patologia , Infertilidade Masculina/terapia , Masculino , Gravidez , Análise do Sêmen , Contagem de Espermatozoides , Injeções de Esperma Intracitoplásmicas , Testosterona/administração & dosagem
6.
J Endocrinol Invest ; 36(1): 55-60, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23211426

RESUMO

The role of cholesterol in female reproductive physiology has been suspected for a long time, while the molecular bases were unknown. Cholesterol is the precursor of ovarian steroid biosynthesis and is also essential for fertility. In the uterus, cholesterol is essential to achieve correct contractions at term, but an excessive uterine cholesterol concentration has been associated with contractility defects. Liver X Receptor (LXR) α and LXR ß are nuclear receptors activated by oxysterols, oxidized derivatives of cholesterol. Since their discovery, the role of LXR in the control of cholesterol homeostasis has been widely described. Beyond their cholesterol-lowering role, more recent data have linked these nuclear receptors to various physiological processes. In particular, they control ovarian endocrine and exocrine functions, as well as uterine contractility. Their contribution to female reproductive cancers will also be discussed. This review will try to enlighten on the LXR as a molecular link between dietary cholesterol and reproductive diseases in women. In the future, a better comprehension of the various physiological processes regulated by the LXR will help to develop new ligands to prevent or to cure these pathologies in women.


Assuntos
Colesterol/metabolismo , Fertilidade/fisiologia , Receptores Nucleares Órfãos/metabolismo , Reprodução/fisiologia , Feminino , Humanos , Receptores X do Fígado , Masculino
7.
Neurology ; 78(19): 1519-26, 2012 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-22539580

RESUMO

OBJECTIVE: To describe the phenotype and phenotype-genotype correlations in patients with amyotrophic lateral sclerosis (ALS) with TARDBP gene mutations. METHODS: French TARDBP+ patients with ALS (n = 28) were compared first to 3 cohorts: 737 sporadic ALS (SALS), 192 nonmutated familial ALS (FALS), and 58 SOD1 + FALS, and then to 117 TARDBP+ cases from the literature. Genotype-phenotype correlations were studied for the most frequent TARDBP mutations. RESULTS: In TARDBP+ patients, onset was earlier (p = 0.0003), upper limb (UL) onset was predominant (p = 0.002), and duration was longer (p = 0.0001) than in patients with SALS. TARDBP+ and SOD1+ groups had the longest duration but diverged for site of onset: 64.3% UL onset for TARDBP+ and 74.1% on lower limbs for SOD1+ (p < 0.0001). The clinical characteristics of our 28 patients were similar to the 117 cases from the literature. In Caucasians, 51.3% of had UL onset, while 58.8% of Asians had bulbar onset (p = 0.02). The type of mutation influenced survival (p < 0.0001), and the G298S1, lying in the TARDBP super rich glycine-residue domain, was associated with the worst survival (27 months). CONCLUSION: Differences in phenotype between the groups as well as the differential influence of TARBDP mutations on survival may help physicians in ALS management and allow refining the strategy of genetic diagnosis.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteínas de Ligação a DNA/genética , Adulto , Idade de Início , Idoso , Esclerose Lateral Amiotrófica/mortalidade , Feminino , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Análise de Sobrevida
8.
Oncogene ; 30(22): 2493-503, 2011 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-21297661

RESUMO

Inherited and acquired changes in pre-mRNA processing have significant roles in human diseases, especially cancer. Characterization of aberrantly spliced mRNAs may thus contribute to understand malignant transformation. We recently reported an anti-oncogenic potential for the SOX9 transcription factor in the colon. For instance, the Sox9 gene knock out in the mouse intestine results in an excess of proliferation with appearance of hyperplasia. SOX9 is expressed in colon cancer cells but its endogenous activity is weak. We looked for SOX9 variants that may impair SOX9 activity in colon cancer cells and we discovered MiniSOX9, a truncated version of SOX9 devoid of transactivation domain as a result of retention of the second intron. A significant overexpression of MiniSOX9 mRNA in human tumor samples compared with their matched normal tissues was observed by real-time reverse transcriptase-PCR. Immunohistochemistry revealed that MiniSOX9 is expressed at high levels in human colon cancer samples whereas it is undetectable in the surrounding healthy tissues. Finally, we discovered that MiniSOX9 behaves as a SOX9 inhibitor, inhibits protein kinase Cα promoter activity and stimulates the canonical Wnt pathway. This potential oncogenic activity of the SOX9 locus gives new insights on its role in colon cancer.


Assuntos
Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Fatores de Transcrição SOX9/genética , Fatores de Transcrição SOX9/metabolismo , Adenocarcinoma/patologia , Processamento Alternativo , Animais , Sequência de Bases , Linhagem Celular Tumoral , Neoplasias do Colo/patologia , Genes Dominantes , Humanos , Íntrons , Camundongos , Camundongos Mutantes , Dados de Sequência Molecular , Mutação , Regiões Promotoras Genéticas , Proteína Quinase C-alfa/antagonistas & inibidores , Proteína Quinase C-alfa/metabolismo , Fatores de Transcrição SOX9/antagonistas & inibidores , Proteínas Wnt/metabolismo
9.
Ann Surg Oncol ; 18(8): 2302-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21347790

RESUMO

PURPOSE: Patients with locally advanced cervical cancer (LACC) are usually treated with concurrent chemoradiotherapy. Extended-field chemoradiotherapy is indicated in case of para-aortic node involvement at initial assessment. 18-Fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (18-FDG PET/CT) is currently considered to be the most accurate method of detection of node or distant metastases. The goal of this study was to evaluate the accuracy of PET at detecting para-aortic lymph node metastases in LACC patients with a negative morphological imaging. METHODS: Patients from five French institutions with LACC and both negative morphologic (magnetic resonance imaging, CT scan) and functional (PET or PET/CT) findings at the para-aortic level and distantly were submitted to a systematic infrarenal para-aortic node dissection either by laparoscopy or laparotomy. On the basis of pathological results, sensitivity, specificity, and positive and negative predictive values of PET/CT were assessed for para-aortic lymph node involvement. RESULTS: A total of 125 LACC patients (stage IB2-IVA disease with two local recurrences) fulfilled the inclusion criteria. All had an ilio-infrarenal para-aortic lymphadenectomy, either by laparoscopy (n = 117) or laparotomy (n = 8). Twenty-one patients (16.8%) had pathologically proven para-aortic metastases. Among them, 14 (66.7%) had negative PET/CT. Overall morbidity of surgery was 7.2%. All but one of the complications were mild and did not delay chemoradiotherapy. Sensitivity, specificity, and positive and negative predictive value of the PET/CT were 33.3, 94.2, 53.8, and 87.5%, respectively, for the detection of microscopic lymph node metastases. CONCLUSIONS: Laparoscopic staging surgery seems warranted in LACC patients with negative PET scan who are candidates for definitive concurrent chemoradiotherapy or exenteration.


Assuntos
Adenocarcinoma de Células Claras/diagnóstico , Adenocarcinoma/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Fluordesoxiglucose F18 , Linfonodos/patologia , Recidiva Local de Neoplasia/diagnóstico , Tomografia por Emissão de Pósitrons , Neoplasias do Colo do Útero/diagnóstico , Adenocarcinoma/terapia , Adenocarcinoma de Células Claras/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/terapia , Criança , Feminino , Seguimentos , Humanos , Metástase Linfática , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/terapia , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Sensibilidade e Especificidade , Taxa de Sobrevida , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Neoplasias do Colo do Útero/terapia , Adulto Jovem
10.
J Endocrinol Invest ; 33(11): 810-4, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20511729

RESUMO

BACKGROUND: 5α steroid reductase deficiency (5αSRD) is an autosomal recessive enzymatic deficiency and mutations in the 5α steroid reductase type 2 gene (SRD5A2) result in male pseudohermaphrodism caused by decreased dihydrotestosterone (DHT) synthesis. AIM: To identify the specific mutations of the SRD5A2 gene in Cypriot patients with 5αSRD. SUBJECTS AND METHODS: Five unrelated patients with 46,XY karyotype were examined. Four of them were born with ambiguous genitalia and 1 patient, who was raised as girl, presented with primary amenorrhea. The hCG test was informative (elevated testosterone/DHT) of 5αSRD in 3 out of 4 subjects. Sequencing of the SRD5A2 gene was completed for all patients. Genomic DNA was also isolated from a total of 204 healthy unrelated Cypriot subjects. Screening for the IVS1-2A>G mutation was performed by using direct sequencing and restriction enzyme analysis. RESULTS: The IVS1-2A>G was identified in homozygosity in 3 patients and in a compound heterozygote state in the other 2 patients, in combination with p.P181L and p.R171S in exon 3, respectively. The carrier frequency in the Cypriot population for the IVS1-2A>G mutation was estimated to be 0.98% or 2 in 204. CONCLUSIONS: The same IVS1-2A>G mutation in the SRD5A2 gene seems to characterize all Cypriot patients with 5αSRD diagnosed so far. Furthermore this relatively rare genetic defect, which has only been reported previously in a single case in the Eastern Mediterranean region, is very likely to be the result of a founder effect.


Assuntos
3-Oxo-5-alfa-Esteroide 4-Desidrogenase/deficiência , Proteínas de Membrana/genética , 3-Oxo-5-alfa-Esteroide 4-Desidrogenase/genética , Adolescente , Adulto , Sequência de Bases , Pré-Escolar , Gonadotropina Coriônica , Chipre , Transtornos do Desenvolvimento Sexual/genética , Feminino , Efeito Fundador , Humanos , Lactente , Recém-Nascido , Masculino , Mutação
11.
Hum Reprod ; 23(8): 1917-23, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18508780

RESUMO

BACKGROUND: Inactivating LH receptor (LHR) mutations have been described so far in men as well as in women. Phenotypes in men have been variable with in nearly all cases impairment of sex differentiation or azoospermia. We report a milder reproductive phenotype both in a male patient and his sister. METHODS AND RESULTS: We describe a family that carries a homozygous mutation G-->A at position -1 at the intron 10-exon 11 boundary of the LHR gene. The male patient presented with delayed puberty, micropenis and oligospermia. Two of his sisters were homozygous for the same mutation and were infertile. Surprisingly, one of them was found to have had regular ovarian cycles for years and showed normal LH values (6.5 and 10.6 mIU/ml for LH and FSH, respectively). In vitro analysis showed that this altered splicing resulted in an LHR from which eight amino acids are deleted from the extracellular domain (Delta Tyr(317)-Ser(324)). In vitro expression has shown that the receptor was expressed and capable of LH-induced signaling, albeit with reduced potency (P < 0.001). CONCLUSIONS: LHR mutations may represent an underestimated cause of infertility in women, in addition to being responsible for male hypogonadism with reduced spermatogenesis.


Assuntos
Processamento Alternativo , Hipogonadismo/genética , Infertilidade Feminina/genética , Oligospermia/genética , Receptores do LH/genética , Adulto , Sequência de Bases , Células Cultivadas , Feminino , Humanos , Masculino , Ciclo Menstrual/genética , Pessoa de Meia-Idade , Dados de Sequência Molecular , Linhagem , Pênis/anormalidades , Puberdade Tardia/genética , Transfecção
12.
Eur J Endocrinol ; 155(6): 839-43, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17132753

RESUMO

BACKGROUND: Activating mutations of the Gsalpha gene (GNAS), which encodes for the alpha-subunit of the stimulatory G protein, have been identified in patients with McCune-Albright syndrome (MAS). Accuracy and sensitivity in the molecular diagnosis of MAS is mandatory for optimal therapeutic strategy and adapted follow-up, especially for incomplete clinical forms of MAS. To date, the highly sensitive nested PCR method with intermediary digestion by a restriction enzyme at the mutation site is one of the most widely used techniques. This study evaluated a new diagnostic method using a peptidic nucleic acid (PNA) and compared it with the nested PCR method. MATERIAL AND METHODS: One hundred and forty-eight DNA samples from eighty-eight patients presenting clinical symptoms compatible with MAS were included. The DNA samples were mainly obtained from peripheral blood, ovarian tissue or cyst liquid, and bone lesions. The nested PCR method required 4 days. PNA clamping required 1.5 days and utilized the higher thermal stability and specificity of PNA-DNA coupling to inhibit PCR product formation. Direct sequencing was subsequently performed in all cases. RESULTS: The sensitivity of mutation detection was 54% (n = 80) for nested PCR and 46.6% (n = 69) for PNA (P > 0.05). The 11 cases where PNA failed to detect the mutation were mainly incomplete and atypical clinical forms of MAS (n = 10/11). The cost per sample was 50 Euros for PNA clamping versus 136 Euros for nested PCR. CONCLUSION: PNA clamping is a rapid, reliable, and economical method to diagnose MAS. It should be the first-line diagnostic method, although negative results, especially for incomplete clinical forms of MAS, should be confirmed by nested PCR.


Assuntos
Displasia Fibrosa Poliostótica/diagnóstico , Displasia Fibrosa Poliostótica/genética , Subunidades alfa Gs de Proteínas de Ligação ao GTP/genética , Testes Genéticos/métodos , Ácidos Nucleicos Peptídicos , Reação em Cadeia da Polimerase/métodos , Criança , Cromograninas , Análise Mutacional de DNA/métodos , Análise Mutacional de DNA/normas , Feminino , Testes Genéticos/normas , Humanos , Masculino , Reação em Cadeia da Polimerase/normas , Reprodutibilidade dos Testes , Mapeamento por Restrição/métodos , Mapeamento por Restrição/normas , Sensibilidade e Especificidade
13.
Spinal Cord ; 44(12): 791-7, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16568142

RESUMO

STUDY DESIGN: This cross-sectional study compared the androgen and growth factor profiles and the bone turnover of patients with spinal cord injury (SCI) versus able-bodied controls (AB). OBJECTIVE: Determine whether androgens, GH, or either IGF-I or IGFBP-3, are implicated in bone turnover alteration in patients with recent SCI. SETTING: Propara Center, Montpellier, France. METHODS: In all, 16 men (31.3 years) with complete SCI, seven paraplegics and nine tetraplegics, who had sustained injury an average of 3 months earlier, and 12 AB who served as controls (27.5 years) participated. Androgens, growth hormone and its mediators were investigated. The bone resorption process was evaluated by urinary and plasma type I collagen C-telopeptide (CTXu, CTXp), while bone formation was evaluated by osteocalcin (OC) and bone alkaline phosphatase. RESULTS: Total testosterone (TT) and the free androgen index (FAI) were significantly lower in the SCI patients, whereas FSH was significantly higher (P<0.05). These hormonal variations were not related to the level of neurological lesion. There was no significant difference in GH, IGF-I, or IGFBP-3 levels. CTXu and CTXp indicated high bone resorption activity in the SCI patients (P<0.05). Regarding bone formation markers, only OC was affected by neurological lesion (P<0.05). Basal hormone levels did not correlate with markers of bone turnover. CONCLUSION: The high bone resorption process observed in SCI patients did not seem directly related to testicular endocrine abnormalities or an altered growth factor profile. Nevertheless, the reduced TT and FAI levels could be aggravating factors in the development of acute bone loss.


Assuntos
Androgênios/metabolismo , Biomarcadores/metabolismo , Reabsorção Óssea/patologia , Colágeno/metabolismo , Traumatismos da Medula Espinal/metabolismo , Adulto , Densidade Óssea , Cálcio/metabolismo , Estudos Transversais , Ensaio de Imunoadsorção Enzimática , Hormônio do Crescimento/metabolismo , Homeostase , Humanos , Masculino
14.
Gynecol Obstet Fertil ; 33(4): 197-207, 2005 Apr.
Artigo em Francês | MEDLINE | ID: mdl-15894203

RESUMO

The paediatric endocrinologist is frequently asked whether pubertal development in a girl is normal, early or too early (precocious). This review will cover all clinical expression of premature development of puberty: central precocious puberty (neurogenic, secondary, and idiopathic) where treatment with GnRHa is considered, early puberty, partial puberty or pubertal variants and peripheral or pseudo precocious puberty related to an antonomous hypersecretion of estrogens by the ovaries. A special attention should be paid also to the role of environmental disruptors in the development of peripheral precocious puberty. GnRHa treatment should be considered only when evidence of central activation of the gonadotropic axis is proved by the LHRH-test.


Assuntos
Puberdade Precoce/diagnóstico , Criança , Doenças do Sistema Endócrino/complicações , Meio Ambiente , Estrogênios/metabolismo , Feminino , Displasia Fibrosa Poliostótica/complicações , Hormônio Liberador de Gonadotropina/agonistas , Hormônio Liberador de Gonadotropina/uso terapêutico , Humanos , Ovário/metabolismo , Puberdade , Puberdade Precoce/etiologia
15.
J Mol Endocrinol ; 32(3): 679-87, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15171708

RESUMO

Androgen insensitivity syndrome (AIS) is an X-linked disease caused by mutations in the androgen receptor (AR) resulting in various degrees of defective masculinization in 46,XY individuals. In the present study, we describe a novel mutation in exon 7 of the AR gene in an Egyptian patient with partial AIS (PAIS). Sequencing analysis of the AR gene revealed a novel missense mutation, P817A, within the ligand-binding domain (LBD). This is the first report of a mutation within the short amino acid motif (codons 815-817) of the beta-strand lying between helices H8 and H9 of the AR LBD. The functional defects of the mutated protein were characterized by in vitro study and included significantly decreased ligand-binding affinity and impaired transactivation potential. Limited proteolysis assays performed with the wild-type and mutant AR receptors incubated with the synthetic agonist R1881 revealed that the P817A mutation resulted in a reduced stabilization of the AR active conformation. Structural analyses showed that this mutation is likely to perturb the beta-sheet interaction between residues 815-817 and 911-913. This structural alteration destabilizes the position of the C-terminal extension, which contains residues critical for androgen function.


Assuntos
Síndrome de Resistência a Andrógenos/genética , Mutação de Sentido Incorreto , Conformação Proteica , Receptores Androgênicos , Animais , Células COS , Chlorocebus aethiops , Humanos , Masculino , Modelos Moleculares , Técnicas de Diagnóstico Molecular , Estrutura Molecular , Receptores Androgênicos/química , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo
16.
J Endocrinol Invest ; 27(1): 57-60, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15053245

RESUMO

The X-linked androgen insensitivity syndrome (AIS) encompasses a heterogeneous group of defects in the androgen receptor (AR) that result in varying degrees of undermasculinization. In the current study, we characterize the R840S mutation on exon 7 of the AR ligand-binding domain. The Egyptian patient, who had been reared as female, presented ambiguous genitalia at 6.5 yr. Diagnosis of partial AIS (PAIS) was based on clinical phenotype and laboratory evidence of good testosterone response and normal testosterone/dihydrotestosterone (T/DHT) ratio. The therapeutic response to testosterone depot injections justified reassignment to male sex. To our knowledge, this mutation has been reported only once in two Brazilian brothers with PAIS. Three other mutations of this residue (R840C; R840G, nonconservative; and R840H, conservative) have been reported in patients with PAIS and, when expressed in vitro, they led to subnormal transactivation of a reporter gene. Each of these mutations was associated with a very diverse spectrum of phenotypes. These data highlight the role of the AR ligand-binding pocket (LBP) in the expression of transcriptional activity during prenatal sex differentiation.


Assuntos
Síndrome de Resistência a Andrógenos/genética , Cromossomos Humanos X , Transtornos do Desenvolvimento Sexual/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Receptores Androgênicos/genética , Substituição de Aminoácidos , Síndrome de Resistência a Andrógenos/tratamento farmacológico , Criança , Transtornos do Desenvolvimento Sexual/tratamento farmacológico , Doenças Genéticas Ligadas ao Cromossomo X/tratamento farmacológico , Humanos , Masculino , Mutação Puntual , Testosterona/uso terapêutico , Resultado do Tratamento
18.
Horm Res ; 59(6): 285-92, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12784093

RESUMO

AIMS: To compare the basal plasma reproductive hormonal profile in three groups of athletes involved in different training programs, and to define the relationship between androgen level and bone mineral density (BMD) in male athletes. METHODS: Basal serum total testosterone (TT), free androgen index (FAI), sex hormone-binding globulin (SHBG), cortisol, cortisol to TT ratio, luteinizing hormone (LH), estrogen and BMD were evaluated in cyclists (CY; n = 11), triathletes (TR; n = 14) and swimmers (SW; n = 13) and compared with less active controls (n = 10). RESULTS: TT and FAI levels were lower (p < 0.05) in CY and TR, whereas the ratio of cortisol to TT was increased in CY only (p < 0.05). No alteration in serum LH, SHBG, estrogen or cortisol concentration was observed. BMD was higher in the proximal femur in TR (p < 0.05). No BMD or hormonal differences were found in SW. CONCLUSION: Only the endurance training of CY and TR induced androgen deficiency without apparent alteration of BMD.


Assuntos
Densidade Óssea , Resistência Física , Esportes , Testosterona/sangue , Adulto , Androgênios/sangue , Ciclismo , Fêmur/metabolismo , Humanos , Hidrocortisona/sangue , Masculino , Corrida , Natação
19.
Clin Genet ; 63(1): 59-63, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12519373

RESUMO

Androgen-insensitivity syndrome (AIS) is a major cause of male pseudohermaphroditism (MPH). Although AIS is usually reported as a monogenic disease resulting from androgen receptor (AR) mutations, on rare occasions it has been observed as part of a multiple congenital anomaly syndrome. We report here a patient who was the first newborn girl of an unrelated couple. Shortly after birth, the diagnoses of congenital glaucoma and pyloric stenosis were made. A detailed history of the father's family revealed that nine members presented glaucoma before 40 years of age. Clinical and ultrasound evaluation showed two inguinal testes, with female external genitalia and no Mullerian derivatives. The patient had a 46,XY karyotype, good testicular response to gonadotrophin stimulation and a remarkably high T : dihydrotestosterone ratio. Sequencing of the five exons of the 5alpha-reductase type 2 gene (SRD5A2) was normal. Conversely, a de novo point mutation was found in exon 6 of the AR gene, resulting in an F804L substitution, which has never been described previously. To our knowledge, the association of complete AIS, congenital glaucoma and pyloric stenosis has also never been reported previously.


Assuntos
Síndrome de Resistência a Andrógenos/genética , Mutação Puntual , Receptores Androgênicos/genética , Egito , Feminino , Glaucoma/genética , Humanos , Lactente , Recém-Nascido , Masculino , Estenose Pilórica/genética
20.
J Soc Biol ; 196(3): 223-40, 2002.
Artigo em Francês | MEDLINE | ID: mdl-12465595

RESUMO

Androgens play a crucial role in the development, maintenance and regulation of male phenotype and reproductive physiology through the androgen receptor, a transcription factor. Testosterone or dihydrotestosterone binding induces a trans-conformation of the androgen receptor and allows its translocation into the nucleus, where it recognizes specific DNA sequences. Recent developments in molecular genetics, as well as structural analysis of the androgen receptor, allow a better understanding of the structure/function relationship of this nuclear receptor. Molecular analyses of androgen insensitivity syndrome, as well as hormone-resistant prostate cancer, Kennedy's disease and isolated male infertility, have been proved useful as privileged models for this purpose. In the absence of identified AR receptor mutations in androgen insensitivity syndromes, abnormalities of transcriptional cofactor should be considered. Finally, identification of androgen-dependent genes will be helpful for evaluating the degree of the molecular defect of androgen action within target cells.


Assuntos
Receptores Androgênicos/fisiologia , Transporte Ativo do Núcleo Celular , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Síndrome de Resistência a Andrógenos/diagnóstico , Síndrome de Resistência a Andrógenos/genética , Síndrome de Resistência a Andrógenos/fisiopatologia , Androgênios/fisiologia , Cromossomos Humanos X/genética , DNA/metabolismo , Análise Mutacional de DNA , Regulação da Expressão Gênica/fisiologia , Genótipo , Humanos , Infertilidade Masculina/etiologia , Masculino , Modelos Moleculares , Fenótipo , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Conformação Proteica , Receptores Androgênicos/química , Receptores Androgênicos/deficiência , Receptores Androgênicos/genética , Transdução de Sinais , Relação Estrutura-Atividade , Fatores de Transcrição/fisiologia , Transcrição Gênica
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