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1.
Pharmacogenomics J ; 21(4): 435-439, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33608663

RESUMEN

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.


Asunto(s)
Citalopram/uso terapéutico , Citocromo P-450 CYP2C19/genética , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/genética , Polimorfismo Genético/genética , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Adulto , Genotipo , Humanos , Masculino
3.
J Community Genet ; 4(3): 321-34, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23904211

RESUMEN

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.
Artículo en Inglés | MEDLINE | ID: mdl-23296430

RESUMEN

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.


Asunto(s)
Anomalías Congénitas/epidemiología , Síndrome de Prader-Willi/epidemiología , Adolescente , Niño , Deleción Cromosómica , Cromosomas Humanos Par 15/genética , Estudios de Cohortes , Comorbilidad , Anomalías Congénitas/diagnóstico , Anomalías Congénitas/genética , Estudios Transversales , Femenino , Estudios de Seguimiento , Expresión Génica/genética , Impresión Genómica/genética , Genotipo , Humanos , Masculino , Fenotipo , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/genética , Estudios Retrospectivos , Factores Sexuales , Disomía Uniparental/genética
6.
Med. infant ; 17(2): 129-134, Junio 2010. Tab
Artículo en Español | LILACS, UNISALUD, BINACIS | ID: biblio-1247658

RESUMEN

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)


Asunto(s)
Humanos , Lactante , Síndrome de Prader-Willi/complicaciones , Síndrome de Prader-Willi/diagnóstico , Síndrome de Prader-Willi/genética , Hormonas Tiroideas , Sistema Hipotálamo-Hipofisario/fisiopatología , Hipotiroidismo/diagnóstico , Incidencia , Estudios Prospectivos
8.
Med. infant ; 14(3): 210-216, sept. 2007. tab, graf
Artículo en Español | BINACIS | ID: bin-123061

RESUMEN

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)


Asunto(s)
Niño , Síndrome de Prader-Willi , Obesidad , Metabolismo de los Hidratos de Carbono , Registros Médicos , Interpretación Estadística de Datos
9.
Med. infant ; 14(3): 210-216, sept. 2007. tab, graf
Artículo en Español | LILACS, BINACIS, UNISALUD | ID: lil-486938

RESUMEN

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


Asunto(s)
Niño , Metabolismo de los Hidratos de Carbono , Obesidad , Síndrome de Prader-Willi , Interpretación Estadística de Datos , Registros Médicos
10.
Genet Mol Res ; 5(2): 390-8, 2006 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-16819717

RESUMEN

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.


Asunto(s)
Cromosomas Humanos Par 15/genética , Repeticiones de Microsatélite/genética , Síndrome de Prader-Willi/etiología , Argentina , Estudios de Casos y Controles , Femenino , Tamización de Portadores Genéticos/métodos , Marcadores Genéticos/genética , Humanos , Masculino , Reacción en Cadena de la Polimerasa , Síndrome de Prader-Willi/genética , Secuencias Repetidas en Tándem/genética
11.
Genet. mol. res. (Online) ; 5(2): 390-398, 2006. tab, graf
Artículo en Inglés | LILACS | ID: lil-442561

RESUMEN

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.


Asunto(s)
Humanos , Masculino , Femenino , /genética , Repeticiones de Microsatélite/genética , Síndrome de Prader-Willi/etiología , Argentina , Tamización de Portadores Genéticos/métodos , Estudios de Casos y Controles , Marcadores Genéticos/genética , Reacción en Cadena de la Polimerasa , Secuencias Repetidas en Tándem/genética , Síndrome de Prader-Willi/genética
12.
Am J Med Genet A ; 129A(1): 83-6, 2004 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-15266622

RESUMEN

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.


Asunto(s)
Antitiroideos/efectos adversos , Atresia de las Coanas/inducido químicamente , Metimazol/efectos adversos , Efectos Tardíos de la Exposición Prenatal , Antitiroideos/uso terapéutico , Femenino , Humanos , Lactante , Recién Nacido , Metimazol/uso terapéutico , Embarazo , Complicaciones del Embarazo/tratamiento farmacológico , Tirotoxicosis/tratamiento farmacológico
13.
Rev Neurol ; 37(1): 14-8, 2003.
Artículo en Español | MEDLINE | ID: mdl-12861501

RESUMEN

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.


Asunto(s)
Síndrome de Angelman/fisiopatología , Electroencefalografía , Adolescente , Síndrome de Angelman/diagnóstico , Niño , Preescolar , Progresión de la Enfermedad , Femenino , Humanos , Lactante , Masculino
15.
Invest Ophthalmol Vis Sci ; 42(13): 3165-72, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11726618

RESUMEN

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.


Asunto(s)
Proteínas del Ojo/genética , Ojo/metabolismo , Glicoproteínas/genética , Presión Intraocular/fisiología , Nervio Óptico/fisiología , ARN Mensajero/metabolismo , Animales , Proteínas del Citoesqueleto , Desnervación , Femenino , Masculino , Ratas , Ratas Endogámicas BN , Ratas Wistar , Distribución Tisular
16.
Biol Bull ; 199(1): 29-40, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10975640

RESUMEN

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.


Asunto(s)
Proteínas de Homeodominio/biosíntesis , Moluscos/metabolismo , Secuencia de Aminoácidos , Animales , Antígenos/inmunología , Pollos , Reacciones Cruzadas , Ganglios de Invertebrados/metabolismo , Gónadas/metabolismo , Proteínas de Homeodominio/inmunología , Datos de Secuencia Molecular , Moluscos/crecimiento & desarrollo , Tejido Nervioso/metabolismo , Erizos de Mar
17.
Front Biosci ; 5: E53-62, 2000 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10877995

RESUMEN

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.


Asunto(s)
Hidrolasas de Éster Carboxílico/fisiología , Fertilidad/fisiología , Espermatozoides/enzimología , Testículo/enzimología , Carboxilesterasa , Hidrolasas de Éster Carboxílico/biosíntesis , Humanos , Masculino , Semen/enzimología , Semen/metabolismo , Espermatozoides/metabolismo , Testículo/metabolismo
18.
Acta Paediatr ; 88(11): 1229-32, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10591424

RESUMEN

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.


Asunto(s)
Gonadotropina Coriónica/biosíntesis , Trastornos del Desarrollo Sexual , Genitales Masculinos/anomalías , Síndrome de Smith-Lemli-Opitz/diagnóstico , Testículo/citología , Testosterona/biosíntesis , Cromosoma X , Cromosoma Y , Células Cultivadas , Preescolar , Gonadotropina Coriónica/análisis , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Orquiectomía , Síndrome de Smith-Lemli-Opitz/fisiopatología , Testículo/patología , Testículo/cirugía , Testosterona/análisis
20.
Reprod Fertil Dev ; 11(3): 133-45, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10864169

RESUMEN

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.


Asunto(s)
Hidrolasas de Éster Carboxílico/genética , Expresión Génica , Genitales Masculinos/enzimología , Secuencia de Aminoácidos , Animales , Hidrolasas de Éster Carboxílico/química , Secuencia Conservada , Humanos , Masculino , Modelos Biológicos , Datos de Secuencia Molecular , Reproducción , Caracteres Sexuales , Espermatogénesis , Espermatozoides/fisiología , Xenobióticos
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