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1.
Pharmacogenomics J ; 21(4): 435-439, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33608663

RESUMO

Citalopram is commonly prescribed to patients suffering from major depressive disorder. Some of them do not respond adequately to therapy with citalopram, while many of them experience type A adverse drug reactions. Current research revealed that CYP2C19 isoenzyme is involved in the biotransformation of citalopram. The objective of our study was to investigate the impact of 681G>A polymorphism of the CYP2C19 gene on the efficacy, safety and the concentration/dose indicator of citalopram. Our study enrolled 130 patients with major depressive disorder and comorbid alcohol use disorder (average age-38.7 ± 14.1 years). Therapy regimen included citalopram in an average daily dose of 31.1 ± 14.4 mg per week. Therapy efficacy and safety were evaluated using the international psychometric scales. For genotyping, we performed the real-time polymerase chain reaction. Our findings revealed the statistically significant results in terms of the treatment efficacy evaluation (HAMD scores at the end of the treatment course): (GG) 8.0 [8.0; 9.0] and (GA) 10.0 [9.0; 11.0], p < 0.001. In the safety profile (the UKU scores), the statistical significance was also obtained: (GG) 3.0 [3.0; 4.0] and (GA) 5.0 [4.0; 5.0], p < 0.001. We revealed a statistical significance for concentration/dose indicator of citalopram in patients with different genotypes: (GG) 2.543 [1.659; 4.239] and (GA) 4.196 [2.643; 5.753], p < 0.001). The effect of CYP2C19 genetic polymorphism on the efficacy and safety profiles of citalopram was demonstrated in a group of 130 patients with major depressive disorder.


Assuntos
Citalopram/uso terapêutico , Citocromo P-450 CYP2C19/genética , Transtorno Depressivo Maior/tratamento farmacológico , Transtorno Depressivo Maior/genética , Polimorfismo Genético/genética , Inibidores Seletivos de Recaptação de Serotonina/uso terapêutico , Adulto , Genótipo , Humanos , Masculino
3.
J Community Genet ; 4(3): 321-34, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23904211

RESUMO

Dissemination of knowledge in genetics to be applied in medicine has created a growing need for capacity building in health care workers. The CAPABILITY ARGENTINA outreach project protocol was designed as a model to introduce genetics in areas without genetic services. Our aim was for genetic health care to become part of primary care in an Argentine province lacking genetic services. The program was innovative as professionals from the referral center (Garrahan Hospital S.A.M.I.C.) traveled to remote areas to train professionals through problem-based education. A logical framework was designed for a local needs assessment. Teaching materials (Powerpoint presentations, printed syllabus, and CD) and a web page were developed. A demonstration project was carried out in the Province of Chaco, Argentina. A total of 485 health workers were trained. The number of consultations increased significantly in participating areas comparing before and after the training period. To support this increase, a complementary project was set up from a public hospital sponsored from within Argentina to build a cytogenetic laboratory in the capital of the Province of Chaco. The model was improved for reproduction in other areas in Argentina. CAPABILITY ARGENTINA is a capacity building model for training of primary care professionals in genetics that may be applied to other medical specialties. The outcomes of the programme have a direct impact on clinical practice.

4.
Pediatrics ; 131(2): e544-9, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23296430

RESUMO

OBJECTIVE: The aim of this study was to assess the prevalence of congenital defects observed in patients with Prader-Willi syndrome (PWS) and to compare this prevalence with that described in the general population. In addition, these findings were correlated with the different etiologic subtypes. METHODS: A total of 180 children with PWS followed for 13 years were included in this study. Diagnosis was confirmed by the methylation test, and genetic subtypes were established by using fluorescence in situ hybridization or multiplex ligation-dependent probe amplification and microsatellite analyses. The prevalence of congenital defects was compared with national and international registries of congenital defects in the general population (Estudio Colaborativo Latinoamericano de Malformaciones Congénitas, European Surveillance of Congenital Anomalies, and the New York Registry). RESULTS: Twenty-two percent of the patients presented congenital defects with a risk of 5.4 to 18.7 times higher than that of the general population. The most frequent congenital defects were heart defects, renoureteral malformations, vertebral anomalies, hip dysplasia, clubfoot, and agenesis/hypoplasia of the corpus callosum. Each of these congenital defects was significantly more frequent in the children with PWS than in the general population. The congenital heart defects were more frequent in girls than in boys with PWS. No significant differences were found when the defects were correlated with the different etiologic subtypes. CONCLUSIONS: An increased prevalence of congenital defects was found in our PWS patients. This finding suggests the need for further studies in PWS children that allow physicians to detect the congenital defects found in this series and, thus, to anticipate complications, with the ultimate aim of enhancing the management of PWS patients.


Assuntos
Anormalidades Congênitas/epidemiologia , Síndrome de Prader-Willi/epidemiologia , Adolescente , Criança , Deleção Cromossômica , Cromossomos Humanos Par 15/genética , Estudos de Coortes , Comorbidade , Anormalidades Congênitas/diagnóstico , Anormalidades Congênitas/genética , Estudos Transversais , Feminino , Seguimentos , Expressão Gênica/genética , Impressão Genômica/genética , Genótipo , Humanos , Masculino , Fenótipo , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/genética , Estudos Retrospectivos , Fatores Sexuais , Dissomia Uniparental/genética
6.
Med. infant ; 17(2): 129-134, Junio 2010. Tab
Artigo em Espanhol | LILACS, UNISALUD, BINACIS | ID: biblio-1247658

RESUMO

Introducción. El síndrome de Prader-Willi SPW) es un trastorno genético causado por la pérdida de expresión de genes de origen paterno en la región cromosómica compleja 15q11-q13. El fenotipo clínico ha sido bien caracterizado, especialmente relacionado con la disfunción hipotalámica. Aunque entre 20 a 30% de los pacientes con SPW tienen hipotiroidismo central (HC), no ha sido bien definida la función tiroidea durante los dos primeros años de vida. Objetivo: evaluar la función hipotalámica-pituitaria-tiroidea en lactantes con SPW. Diseño del estudio: 18 pacientes con SPW entre 0,16 y 2 años de edad fueron incluídos en un estudio prospectivo. El diagnóstico de SPW se basó en los hallazgos clínicos y en el análisis molecular. Se calcularon los escores de desviacion estándar (SDS) de la T4 total (T), T4 libre (L), T3 y TSH en suero en todos los pacientes incluídos en el estudio. Resultados: En 14 de los 18 pacientes con SPW, se encontraron niveles de T4T y/o T4L menores a -2 SDS (44,4 y 55,5%, respectivamente), mientras que solamente en 1 paciente con SPW el nivel de T3 estaba por debajo de -2 SDS. Conclusión: Este estudio muestra que la incidencia de HC es alta en lactantes con SPW. Los pediatras deben tener en cuenta el diagnostico de HC en este período crítico de la acción de la hormona tiroidea en el desarrollo neurológico (AU)


Introduction. Prader-Willi syndrome (PWS) is a genetic disorder caused by the loss of expression of paternally transcribed genes in a highly imprinted region of chromosome 15q11- q13. The clinical phenotype has been well characterized, mostly related to hypothalamic dysfunction. Even though central hypothyroidism (CH) has been documented in 20 to 30% of PWS patients, thyroid function has not been well characterized during the first 2 years of life. Objective: to evaluate hypothalamic-pituitary-thyroid function in infant PWS patients. Study design: Eighteen PWS patients, aged 0.16 to 2 years, were included in a prospective study. PWS diagnosis was based on clinical features and molecular analysis. Serum total (T) T4, free (F) T4, T3 and TSH standard deviation scores (SDS) were calculated in all PWS patients included in the study. Results: In 14 out of 18 PWS patients, serum TT4 and/or FT4 levels less than -2 SDS ( 44.4 and 55.5 %, respectively) were found, while in only 1 PWS patient serum T3 levels was below -2 SDS. Conclusion: This study shows that there is a high incidence of CH in infant PWS patients. Pediatricians should be aware of this diagnosis in this critical period of thyroid hormone action on neurological development (AU)


Assuntos
Humanos , Lactente , Síndrome de Prader-Willi/complicações , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/genética , Hormônios Tireóideos , Sistema Hipotálamo-Hipofisário/fisiopatologia , Hipotireoidismo/diagnóstico , Incidência , Estudos Prospectivos
8.
Med. infant ; 14(3): 210-216, sept. 2007. tab, graf
Artigo em Espanhol | LILACS, BINACIS, UNISALUD | ID: lil-486938

RESUMO

Estudiar el metabolismo de los hidratos de carbono y la sensibilidad y secreción de insulina en niños y adolescentes con sindrome de Prader Willi (SPW) comparados con niños con obesidad multifactorial (OM) como grupo control. Material y métodos: fueron evaluados 75 niños con SPW y 395 con OM con test de tolerancia a la glucosa oral. La resistencia a la insulina y función de celula fueron medidos por el modelo homeostático (HOMA IR Y HOMA beta cell), índice insulina /glucosa, insulina en ayunas e índice de sensibilidad a la insulina. Resultados: La prevalencia de diabetes fue 0% en SPW y 1.5% en OM mientras que la intolerancia a la glucosa fue de 9,3% en el primer gurpo y 7,6%en los obesos controles (p no significativa) El valor de la insulina basal (12 más menos 8,2 vs 22.3 más menos 25 mU/ml) ay el HOMA- IR (2.47 más menos 1.6 vs 4.18 más menos 5.05) fue más bajo en los pacientes con S PW (p 0.004 y 0.04, respectivamente), mientras el índice HOMA fue más bajo en el SPW que en los OM (59 más menos 42 vs 102 más menos 119, p 0.03). El índice ISI composite fue más alto en el SPW comparado al grupo de OM (6 más menos 5.7 vs 4.18 más menos 5.05, p 0.04). Conclusión: los niños con Sindrome de Prader Willi mostraron a igual nivel de obesidad menor resistencia a la insulina pero mayor alteración en la secreción que la obesidad multifactorial. Esto sugiere mecanismos diferentes en la alteración del metabolismo de los H de C de la población con el sindrome


Assuntos
Criança , Metabolismo dos Carboidratos , Obesidade , Síndrome de Prader-Willi , Interpretação Estatística de Dados , Prontuários Médicos
9.
Med. infant ; 14(3): 210-216, sept. 2007. tab, graf
Artigo em Espanhol | BINACIS | ID: bin-123061

RESUMO

Estudiar el metabolismo de los hidratos de carbono y la sensibilidad y secreción de insulina en niños y adolescentes con sindrome de Prader Willi (SPW) comparados con niños con obesidad multifactorial (OM) como grupo control. Material y métodos: fueron evaluados 75 niños con SPW y 395 con OM con test de tolerancia a la glucosa oral. La resistencia a la insulina y función de celula fueron medidos por el modelo homeostático (HOMA IR Y HOMA beta cell), índice insulina /glucosa, insulina en ayunas e índice de sensibilidad a la insulina. Resultados: La prevalencia de diabetes fue 0% en SPW y 1.5% en OM mientras que la intolerancia a la glucosa fue de 9,3% en el primer gurpo y 7,6%en los obesos controles (p no significativa) El valor de la insulina basal (12 más menos 8,2 vs 22.3 más menos 25 mU/ml) ay el HOMA- IR (2.47 más menos 1.6 vs 4.18 más menos 5.05) fue más bajo en los pacientes con S PW (p 0.004 y 0.04, respectivamente), mientras el índice HOMA fue más bajo en el SPW que en los OM (59 más menos 42 vs 102 más menos 119, p 0.03). El índice ISI composite fue más alto en el SPW comparado al grupo de OM (6 más menos 5.7 vs 4.18 más menos 5.05, p 0.04). Conclusión: los niños con Sindrome de Prader Willi mostraron a igual nivel de obesidad menor resistencia a la insulina pero mayor alteración en la secreción que la obesidad multifactorial. Esto sugiere mecanismos diferentes en la alteración del metabolismo de los H de C de la población con el sindrome (AU)


Assuntos
Criança , Síndrome de Prader-Willi , Obesidade , Metabolismo dos Carboidratos , Prontuários Médicos , Interpretação Estatística de Dados
10.
Genet Mol Res ; 5(2): 390-8, 2006 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-16819717

RESUMO

Prader-Willi syndrome (PWS) is a multisystemic disorder caused by the loss of expression of paternally transcribed genes in the PWS critical region of chromosome 15. Various molecular mechanisms are known to lead to PWS: deletion 15q11-q13 (75% of cases), maternal uniparental disomy (matUPD15) (23%) and imprinting defects (2%). FISH and microsatellite analysis are required to establish the molecular etiology, which is essential for appropriate genetic counseling and care management. We characterized an Argentinean population, using five microsatellite markers (D15S1035, D15S11, D15S113, GABRB3, D15S211) chosen to develop an appropriate cost-effective method to establish the parental origin of chromosome 15 in nondeleted PWS patients. The range of heterozygosity for these five microsatellites was 0.59 to 0.94. The average heterozygosity obtained for joint loci was 0.81. The parental origin of chromosome 15 was established by microsatellite analysis in 19 of 21 non-deleted PWS children. We also examined the origin of the matUPD15; as expected, most of disomies were due to a maternal meiosis I error. The molecular characterization of this set of five microsatellites with high heterozygosity and polymorphism information content improves the diagnostic algorithm of Argentinean PWS children, contributing significantly to adequate genetic counseling of such families.


Assuntos
Cromossomos Humanos Par 15/genética , Repetições de Microssatélites/genética , Síndrome de Prader-Willi/etiologia , Argentina , Estudos de Casos e Controles , Feminino , Triagem de Portadores Genéticos/métodos , Marcadores Genéticos/genética , Humanos , Masculino , Reação em Cadeia da Polimerase , Síndrome de Prader-Willi/genética , Sequências de Repetição em Tandem/genética
11.
Genet. mol. res. (Online) ; 5(2): 390-398, 2006. tab, graf
Artigo em Inglês | LILACS | ID: lil-442561

RESUMO

Prader-Willi syndrome (PWS) is a multisystemic disorder caused by the loss of expression of paternally transcribed genes in the PWS critical region of chromosome 15. Various molecular mechanisms are known to lead to PWS: deletion 15q11-q13 (75% of cases), maternal uniparental disomy (matUPD15) (23%) and imprinting defects (2%). FISH and microsatellite analysis are required to establish the molecular etiology, which is essential for appropriate genetic counseling and care management. We characterized an Argentinean population, using five microsatellite markers (D15S1035, D15S11, D15S113, GABRB3, D15S211) chosen to develop an appropriate cost-effective method to establish the parental origin of chromosome 15 in nondeleted PWS patients. The range of heterozygosity for these five microsatellites was 0.59 to 0.94. The average heterozygosity obtained for joint loci was 0.81. The parental origin of chromosome 15 was established by microsatellite analysis in 19 of 21 non-deleted PWS children. We also examined the origin of the matUPD15; as expected, most of disomies were due to a maternal meiosis I error. The molecular characterization of this set of five microsatellites with high heterozygosity and polymorphism information content improves the diagnostic algorithm of Argentinean PWS children, contributing significantly to adequate genetic counseling of such families.


Assuntos
Humanos , Masculino , Feminino , /genética , Repetições de Microssatélites/genética , Síndrome de Prader-Willi/etiologia , Argentina , Triagem de Portadores Genéticos/métodos , Estudos de Casos e Controles , Marcadores Genéticos/genética , Reação em Cadeia da Polimerase , Sequências de Repetição em Tandem/genética , Síndrome de Prader-Willi/genética
12.
Am J Med Genet A ; 129A(1): 83-6, 2004 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-15266622

RESUMO

We report three patients with bilateral choanal atresia in children prenatally exposed to methimazole (MMI) in order to define a MMI embryopathy clinical pattern. The combination of choanal atresia and other specific malformations strongly resembles previously reported patients exposed to MMI in utero. At present, propylthiouracil is considered the best treatment in pregnancies. However in Argentina and some other countries MMI is the only antithyroid drug, possibly posing a significant risk to the unborn fetus.


Assuntos
Antitireóideos/efeitos adversos , Atresia das Cóanas/induzido quimicamente , Metimazol/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal , Antitireóideos/uso terapêutico , Feminino , Humanos , Lactente , Recém-Nascido , Metimazol/uso terapêutico , Gravidez , Complicações na Gravidez/tratamento farmacológico , Tireotoxicose/tratamento farmacológico
13.
Rev Neurol ; 37(1): 14-8, 2003.
Artigo em Espanhol | MEDLINE | ID: mdl-12861501

RESUMO

AIMS: The purpose of this study is to report on 35 patients with Angelman syndrome (AS) in whom we evaluated the electroclinical characteristics and the progression of their epilepsy. PATIENTS AND METHODS: The following factors were evaluated: sex, family background, neurological examination, age at onset and semiology of the epileptic seizures, EEG, types of epilepsy according to the international classification and response to therapy. We investigated the karyotype, and conducted FISH and methylation tests for AS. RESULTS: The 35 patients had an average follow up time of 5.6 years. Epilepsy was diagnosed in 25 cases, with an average age of onset of 1.6 years. The epileptic syndromes were: epilepsy with myoclonic seizures in 13, of which seven presented a myoclonic state in their history, focal epilepsy in seven, West's syndrome in three, and Lennox Gastaut syndrome in two. Intercritical EEG showed generalised MSW and SW paroxysms in 13, unilateral spikes in seven, hypsarrhythmia in three, generalised fast rhythm paroxysms and slow SW activity in two. Basal electroencephalographic activity was: slow hypervoltage waves with or without inserted spikes situated at the rear in 19, at the front in six, diffuse in six, and normal in four cases. CONCLUSIONS: 71.4% of patients with AS suffered epileptic seizures; epilepsy with myoclonic seizures was the most frequently observed epileptic syndrome and hypervoltage slow wave activity with or without spikes inserted in the posterior quadrants was a characteristic encephalographic pattern. In patients with mental retardation, with or without epilepsy and these electroencephalographic findings, even in the absence of characteristic clinical signs, methylation and FISH analyses for AS should be performed.


Assuntos
Síndrome de Angelman/fisiopatologia , Eletroencefalografia , Adolescente , Síndrome de Angelman/diagnóstico , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Lactente , Masculino
15.
Invest Ophthalmol Vis Sci ; 42(13): 3165-72, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11726618

RESUMO

PURPOSE: To isolate the rat Myoc/Tigr gene and investigate changes in its expression pattern in normal eyes and in eyes with either pressure-induced optic nerve damage or optic nerve transection. METHODS: Expression pattern of the rat Myoc/Tigr gene was investigated by Northern blot hybridization. Optic nerve damage and death of ganglion cells in the retina were induced unilaterally, by injection of hypertonic saline solution, episcleral vein cauterization, or optic nerve transection. The levels of mRNA for Myoc/Tigr were compared between several tissues of the control and surgically altered eyes, by using semiquantitative RT-PCR, real-time PCR, and Northern blot analysis. RESULTS: The rat Myoc/Tigr gene is 10 kb long and contains three exons. Among the eye tissues analyzed, Myoc/Tigr mRNA was detected in the combined tissues of the eye angle, sclera, cornea, retina, and optic nerve head. With pressure-induced optic nerve degeneration, the level of Myoc/Tigr mRNA decreased in the retina and the combined tissues of the eye angle, but increased in the optic nerve head. After optic nerve transection, the level of Myoc/Tigr mRNA increased in the retina, but did not change in the combined tissues of the eye angle. CONCLUSIONS: The decreased level of Myoc/Tigr mRNA in the retina after induction of elevated intraocular pressure compared with that in the control retina cannot be explained by ganglion cell death alone. Differences in Myoc/Tigr mRNA levels in eye tissues after elevation of intraocular pressure or optic nerve transection may reflect the activation of different signaling pathways involved in regulation of this gene.


Assuntos
Proteínas do Olho/genética , Olho/metabolismo , Glicoproteínas/genética , Pressão Intraocular/fisiologia , Nervo Óptico/fisiologia , RNA Mensageiro/metabolismo , Animais , Proteínas do Citoesqueleto , Denervação , Feminino , Masculino , Ratos , Ratos Endogâmicos BN , Ratos Wistar , Distribuição Tecidual
16.
Biol Bull ; 199(1): 29-40, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10975640

RESUMO

In a few well-known cases, the biological consequences of the disruption of lim-1 homeodomain (HD) genes have demonstrated the important roles of these genes in vertebrate development, especially in the nervous tissue, kidney, and gonads. Functional assay approaches require information not only about lim-1 gene organization, but also about properties and tissue localization of Lim-1 proteins. Although lim-1 genes have been identified in certain phyla of invertebrates, no information is available on Lim-1 proteins and genes in bivalve molluscs. Our study represents the beginning stage of identification of the Lim-1-related proteins in marine bivalves. Using antibodies against the C-terminal region of the Xenopus laevis Lim-1 protein, we describe cross-reactive antigen patterns in adults and early embryos of the mussel Mytilus galloprovincialis, as well as in sea urchin and chick embryos. In adult mussels, nervous ganglia and gonads display the most prominent Lim-1 immunoreactivity. Further, the antibodies verified the prediction that mussel Lim-1 antigens, like Lim-1 HD proteins in general, can be localized in the nucleus. Moreover, antibody detection allowed us to identify the Lim-1-like antigens in unfertilized mature eggs, as well as in very early embryos of bivalve molluscs and sea urchins (Strongylocentrotus purpuratus). In mussel eggs and embryos, Lim-1 antigens are expressed in multiple forms (40, 45, and 65 kDa), as detected by SDS-PAGE followed by Western blot. Taken together, the observations emphasize the conservation of the Lim-1 protein expression pattern in the nervous tissue and gonads of different animal groups, and demonstrate that Lim-1-like polypeptides can be maternally accumulated in eggs and, therefore, are present in very early embryos before zygotic expression of the genes begins.


Assuntos
Proteínas de Homeodomínio/biossíntese , Moluscos/metabolismo , Sequência de Aminoácidos , Animais , Antígenos/imunologia , Galinhas , Reações Cruzadas , Gânglios dos Invertebrados/metabolismo , Gônadas/metabolismo , Proteínas de Homeodomínio/imunologia , Dados de Sequência Molecular , Moluscos/crescimento & desenvolvimento , Tecido Nervoso/metabolismo , Ouriços-do-Mar
17.
Front Biosci ; 5: E53-62, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10877995

RESUMO

This essay addresses the carboxylesterase redundancy in the male reproductive tract seemingly conserved across phyla. Evidence is provided which suggests that carboxylesterases are recruited by the male reproductive system in certain animal groups. These provide advantageous metabolic capabilities to sperm protection, sperm maturation, and sperm use. Rather than an archival record of the available data, we seek possible answers to the central question: Why is carboxylesterase over-expression adaptive with the functioning of the male reproductive tract with respect to male fertility? We discuss patterns of carboxylesterase over-expression and accumulation in different compartments of the male reproductive tract. We also provide evidence of how these patterns are associated with a long sperm path to egg through different local effects. The hyper-expression of carboxylesterases can play different physiological roles depending on its localization in the male reproductive system. However, all the "acquired" functions can serve the same purpose; creating conditions which maximize the fertilizing potential of the sperm. To confirm our concept and more clearly illuminate "moonlighting" roles of carboxylesterases in the male reproductive tract, requires a more extensive comparative analysis of a variety of carboxylesterases in a larger number of species.


Assuntos
Hidrolases de Éster Carboxílico/fisiologia , Fertilidade/fisiologia , Espermatozoides/enzimologia , Testículo/enzimologia , Carboxilesterase , Hidrolases de Éster Carboxílico/biossíntese , Humanos , Masculino , Sêmen/enzimologia , Sêmen/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo
18.
Acta Paediatr ; 88(11): 1229-32, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10591424

RESUMO

The pathogenesis of the development of ambiguous genitalia reported in some 46,XY patients with Smith-Lemli-Opitz syndrome is not understood. Presumably, it is related to the 7-dehydrocholesterol reductase deficiency present in these patients. In this study we have evaluated testicular function, both in vivo and in vitro, in a 46,XY patient with ambiguous genitalia, reared as a girl. The diagnosis was based on clinical features, low serum cholesterol and high serum 7-dehydrocholesterol levels. Serum hormone values, determined during the first month of age, showed normal basal testosterone (1.95 ng/ml), LH (0.91 U/l) and FSH (2.51 U/l). However, serum testosterone did not increase after hCG administration (1.98 ng/ml). On the other hand, the patient had a positive biological response to exogenous testosterone (decrease in sex hormone-binding globulin serum levels). She was orchidectomized at the age of 33 mo. Testicular cells were dispersed and maintained in culture for 6 d. These cells showed a very good capacity to secrete testosterone into the culture medium (X +/- SD, 26.1 +/- 11.7 vs. 4.36 +/- 1.70 pmol/10(6) cells/24 h in a control group of testicular cells prepared from testes collected at necropsy). The patient's cells failed to respond to LH stimulation (18.6 +/- 4.0 pmol/10(6) cells/24 h), although they did respond to other stimuli. It is concluded that the severe cholesterol deficiency of this patient did not impair the capacity of the testes to synthesize testosterone. However, the LH/hCG receptor or its subsequent message was activated neither in vivo nor in vitro. This finding suggests that the foetal testes might have failed to respond to placental hCG at the time of male external genital differentiation. This failure could have been responsible for the ambiguous genitalia present in this patient.


Assuntos
Gonadotropina Coriônica/biossíntese , Transtornos do Desenvolvimento Sexual , Genitália Masculina/anormalidades , Síndrome de Smith-Lemli-Opitz/diagnóstico , Testículo/citologia , Testosterona/biossíntese , Cromossomo X , Cromossomo Y , Células Cultivadas , Pré-Escolar , Gonadotropina Coriônica/análise , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Orquiectomia , Síndrome de Smith-Lemli-Opitz/fisiopatologia , Testículo/patologia , Testículo/cirurgia , Testosterona/análise
20.
Reprod Fertil Dev ; 11(3): 133-45, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10864169

RESUMO

Data on expression patterns of carboxylesterases in the male reproductive tract of different animal groups (i.e. bivalve mollusks, fruitflies and rodents) are summarized to highlight some particularly interesting questions in the context of sperm differentiation, maturation and function. The male reproductive system, in spite of extreme variation in the anatomical/morphological organization in different species, is characterized by similar patterns of male-dependent carboxylesterase overexpression. The phenomenon of conserved carboxylesterase overexpression indicates similar male sex-associated functions of the enzymes. There is possible evidence of carboxylesterase recruitment by male reproductive-tract tissues indicating that it could be adaptive for spermatogenesis, sperm maturation and sperm use. Moreover, this idea can be extended to include a sperm cell lineage protection. This issue is discussed in the light of recent data on environmental reproductive xenobiotics that can provide a basis for a hypothetical explanation of carboxylesterase overexpression in the male reproductive tract. Based on a well-known role of carboxylesterases in detoxification of environmental chemicals such as organophosphate pesticides, it is proposed that various male genital tract carboxylesterases may be characterized by a similar physiological function to protect the male reproductive system against xenobiotic influences that could provoke its dysfunction, thus altering sperm differentiation and maturation.


Assuntos
Hidrolases de Éster Carboxílico/genética , Expressão Gênica , Genitália Masculina/enzimologia , Sequência de Aminoácidos , Animais , Hidrolases de Éster Carboxílico/química , Sequência Conservada , Humanos , Masculino , Modelos Biológicos , Dados de Sequência Molecular , Reprodução , Caracteres Sexuais , Espermatogênese , Espermatozoides/fisiologia , Xenobióticos
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