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1.
J Obstet Gynaecol Res ; 41(12): 1891-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26369382

RESUMO

AIM: The objective of this study was to determine the ability of biochemical analytes to identify adverse outcomes in pregnancies with Turner syndrome. METHODS: Maternal serum and amniotic fluid (AF) marker concentrations were measured in 73 singleton pregnancies with Turner syndrome (10-22 weeks of gestation). Fetal Turner syndrome was definitively established by cytogenetic analysis. Two subgroups, fetuses with hydrops fetalis versus fetuses with cystic hygroma, were compared. Receiver operating characteristic curves and relative risk were established for a cut-off multiples of the median ≥3.5 for ß-subunit of human chorionic gonadotropin (hCG) or AF alpha-fetoprotein (AFP). RESULTS: Forty-nine (67%) of 73 pregnant women had an abnormal maternal serum. While levels of pregnancy-associated plasma protein-A and free ß-subunit (fß)-hCG were not different to those of the control group, AFP, unconjugated estriol and ß-hCG concentrations were significantly different in the study group (P < 0.05), when compared to those of unaffected pregnancies. Levels of ß-hCG in pregnancies with hydrops fetalis were significantly higher than in those with cystic hygroma (P <0.0001), as were AF-AFP concentrations (P <0.0015). In addition, abnormalities in both maternal serum ß-hCG and AF-AFP predicted fetal death. The relative risk of adverse obstetric outcome was 10.667 (P = 0.0004; 95% confidence interval [CI]: 1.554-73.203) for ß-hCG and 2.19 (P = 0.0256; 95% CI: 1.001 to 4.779), for AF-AFP. CONCLUSION: Maternal serum ß-hCG and AF-AFP levels may preferentially identify those Turner syndrome pregnancies with the highest risk of fetal death.


Assuntos
Líquido Amniótico/química , Gonadotropina Coriônica Humana Subunidade beta/sangue , Doenças Fetais , Síndrome de Turner/complicações , alfa-Fetoproteínas/análise , Feminino , Humanos , Gravidez , Segundo Trimestre da Gravidez , Curva ROC
2.
Am J Med Genet A ; 161A(6): 1470-4, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23636874

RESUMO

Nasopalpebral lipoma-coloboma syndrome is an extremely uncommon autosomal dominant condition characterized by congenital upper eyelid and nasopalpebral lipomas, colobomata of upper and lower eyelids, telecanthus, and maxillary hypoplasia. A few familial and sporadic cases of this malformation syndrome have been previously reported. Here, the clinical, radiological, and histopathological features of a sporadic Mexican patient with the nasopalpebral lipoma-coloboma syndrome are described. To our knowledge, this is the first time that craniofacial 3D computed tomography imaging was used for a detailed assessment of the facial lipoma.


Assuntos
Anormalidades Múltiplas/diagnóstico por imagem , Coloboma/diagnóstico por imagem , Neoplasias Palpebrais/diagnóstico por imagem , Hamartoma/diagnóstico por imagem , Lipoma/diagnóstico por imagem , Tumor de Músculo Liso/diagnóstico por imagem , Anormalidades Múltiplas/patologia , Coloboma/patologia , Neoplasias Palpebrais/patologia , Pálpebras/anormalidades , Pálpebras/diagnóstico por imagem , Feminino , Hamartoma/patologia , Humanos , Lactente , Cariotipagem , Lipoma/patologia , Radiografia , Tumor de Músculo Liso/patologia
3.
Nepal J Ophthalmol ; 13(24): 118-127, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35996778

RESUMO

INTRODUCTION: Functional and anatomical success after canalicular laceration repair using only Crawford bicanalicular stents was evaluated in a ophthalmological teaching center. The objective of this study was to evaluate functional and anatomical success after canalicular laceration repair using Crawford bicanalicular stents. MATERIALS AND METHODS: Records of patients with canalicular laceration repair performed from 2010 to 2019 at Ophthalmology Institute Conde de Valenciana in Mexico City were reviewed. Demographic data, injury mechanism and complications were recorded. Anatomical success was assessed with canalicular irrigation and functional success was evaluated using Munk score. Phi correlation coefficient was used to compare the correlation between epiphora and lack of permeability of injured canaliculus and the presence of complications at 6th month postoperative visit. RESULTS: Two-hundred eight patients with lacrimal canalicular injury reconstruction were documented during the study period. The most common age of presentation and etiology was from 21 to 30 years old and injury with a sharp object, respectively. 96 patients were included for the correlation analysis. At 6th month, anatomical success was found in 75% and functional success was found in 77.8%. A statistically significant and directly proportional linear was found between the presence of epiphora and lack of permeability of injured canaliculus, (rφ 0.76, p <0.05) and between the presence of epiphora and postoperative complications, (rφ 0.509, p <0.05). CONCLUSION: Crawford bicanalicular stents are a valid and accessible option for canalicular laceration repair. Our success rate of lacrimal canalicular lacerations repaired with bicanalicular stents in a Mexican teaching hospital matches worldwide literature. Factors involved in the functional and anatomical success of the reconstruction include presence of postoperative complications and permeability of canaliculus after surgery.


Assuntos
Traumatismos Oculares , Lacerações , Doenças do Aparelho Lacrimal , Aparelho Lacrimal , Adulto , Traumatismos Oculares/cirurgia , Humanos , Intubação , Lacerações/diagnóstico , Lacerações/cirurgia , Aparelho Lacrimal/cirurgia , Doenças do Aparelho Lacrimal/diagnóstico , Doenças do Aparelho Lacrimal/cirurgia , México/epidemiologia , Complicações Pós-Operatórias , Encaminhamento e Consulta , Stents , Adulto Jovem
4.
J Pediatr Endocrinol Metab ; 23(8): 773-82, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21073120

RESUMO

We have prospectively assessed the influence of GHR and VDR gene polymorphisms on the response to rhGH therapy in Venezuelan children with growth hormone deficiency (GHD, n=28) and Turner syndrome (TS, n=25). Clinical data during rhGH treatment were compared in GH and TS patients with different genotypes. PCR amplifications were performed to obtain the genotype frequencies of the polymorphisms. Clinical data at the start of treatment and rhGH doses were indistinguishable among patients with GHD or TS with different GHR or VDR genotypes. After the first two years of rhGH treatment, clinical data in both GHD and TS patients were not different according GHR or VDR genotypes. In addition, there was no significant difference among the subjects when both these genotypes were combined. Gene polymorphisms in low penetrance genes do not contribute to the rhGH therapy response in patients with GHD and TS.


Assuntos
Proteínas de Transporte/genética , Nanismo Hipofisário/genética , Hormônio do Crescimento Humano/uso terapêutico , Polimorfismo Genético , Receptores de Calcitriol/genética , Síndrome de Turner/genética , Criança , Pré-Escolar , Análise Mutacional de DNA , Nanismo Hipofisário/tratamento farmacológico , Feminino , Genótipo , Humanos , Masculino , Estudos Prospectivos , Proteínas Recombinantes , Resultado do Tratamento , Síndrome de Turner/tratamento farmacológico
5.
Invest Clin ; 50(1): 55-63, 2009 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-19418727

RESUMO

Mutations in the K-ras oncogene are common in colo-rectal cancer, which affect the biological behaviour and may influence the susceptibility to therapy in these tumors. The objective of this work was to identify the types of K-ras mutations observed in referred patients with colo-rectal cancer and to relate them to their degree of histological differentiation and clinical stage. Histopathological and clinical data were obtained from medical records. DNA was obtained from both, fresh tissue and tumor tissue embedded in paraffin. The K-ras gene was amplified through the polymerase chain reaction (PCR) and the amplified fragments were digested with restriction enzymes. We found mutations in codons 12 and 13 of the K-ras oncogene in 23.33% of patients. Of these, 28.57% were located at codon 12, 57.14% were at codon 13 and 14.29% at both codons. They were more frequent in tumors located in the left hemicolon and, according to their histological type, were more frequent in well differentiated adenocarcinomas (58.70%) and in mucinous (28.57%). The identified mutations were more frequent in advanced stages (C2) of Dukes' classification. The molecular analysis of the K-ras oncogene made mutations evident, which could be useful in the diagnosis and prognosis of colorectal tumors. The frequency of mutations found in this work is similar to some of those reported worldwide; however, they differ in the more frequent type of mutation, which, in our study, was located at codon 13 in more than 50% of the cases.


Assuntos
Adenocarcinoma/genética , Neoplasias Colorretais/genética , Genes ras , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adenocarcinoma Mucinoso/epidemiologia , Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/patologia , Diferenciação Celular , Códon/genética , Neoplasias do Colo/epidemiologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Venezuela/epidemiologia
6.
Int J Gynaecol Obstet ; 103(3): 241-5, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18817910

RESUMO

OBJECTIVE: To assess the usefulness of triple-marker screening for Down syndrome in Venezuela. METHOD: Maternal serum concentrations of alpha fetoprotein (AFP), beta human chorionic gonadotropin (beta-hCG), and unconjugated estriol (uE3) were measured weekly in 3895 women from the 15th to the 20th week of pregnancy. Population-specific likelihood ratios were determined and used to calculate the risk of fetal Down syndrome for each pregnancy. RESULTS: The median multiple of the median values for AFP, beta-hCG, and uE3 concentrations were 0.69, 2.10, and 0.67 for the affected pregnancies. The likelihood ratio for a positive result was 1:19. The detection and false-positive rates were 69.23% and 5.8%. CONCLUSION: These findings were consistent with reported data and therefore confirmed triple-marker serum screening as effective and suitable for prenatal care in Venezuela. Latin American governments and Health Agencies should recommend offering this screening method to all pregnant women.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Síndrome de Down/diagnóstico , Estriol/sangue , Diagnóstico Pré-Natal/métodos , alfa-Fetoproteínas/análise , Adulto , Biomarcadores/sangue , Síndrome de Down/sangue , Síndrome de Down/epidemiologia , Reações Falso-Positivas , Feminino , Humanos , Modelos Logísticos , Idade Materna , Valor Preditivo dos Testes , Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , Valores de Referência , Fatores de Risco , Estatísticas não Paramétricas , Venezuela/epidemiologia
7.
Elife ; 42015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25986605

RESUMO

Two ER membrane-resident transmembrane kinases, IRE1 and PERK, function as stress sensors in the unfolded protein response. IRE1 also has an endoribonuclease activity, which initiates a non-conventional mRNA splicing reaction, while PERK phosphorylates eIF2α. We engineered a potent small molecule, IPA, that binds to IRE1's ATP-binding pocket and predisposes the kinase domain to oligomerization, activating its RNase. IPA also inhibits PERK but, paradoxically, activates it at low concentrations, resulting in a bell-shaped activation profile. We reconstituted IPA-activation of PERK-mediated eIF2α phosphorylation from purified components. We estimate that under conditions of maximal activation less than 15% of PERK molecules in the reaction are occupied by IPA. We propose that IPA binding biases the PERK kinase towards its active conformation, which trans-activates apo-PERK molecules. The mechanism by which partial occupancy with an inhibitor can activate kinases may be wide-spread and carries major implications for design and therapeutic application of kinase inhibitors.


Assuntos
Trifosfato de Adenosina/farmacologia , Endorribonucleases/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Resposta a Proteínas não Dobradas/efeitos dos fármacos , eIF-2 Quinase/antagonistas & inibidores , Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/síntese química , Animais , Bioensaio , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Estresse do Retículo Endoplasmático , Endorribonucleases/genética , Endorribonucleases/metabolismo , Ativação Enzimática , Escherichia coli/genética , Escherichia coli/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Expressão Gênica , Genes Reporter , Células HEK293 , Humanos , Camundongos , Mimetismo Molecular , Inibidores de Proteínas Quinases/síntese química , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Fatores de Transcrição de Fator Regulador X , Radioisótopos de Enxofre , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas/genética , eIF-2 Quinase/genética , eIF-2 Quinase/metabolismo
8.
J Pediatr Endocrinol Metab ; 17(11): 1571-4, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15570996

RESUMO

BACKGROUND: Female pseudohermaphroditism is a disorder in which 46,XX females with ovaries do not develop as normal women. This disorder is caused by overexposure of a female fetus to androgens during intrauterine life. We describe a masculinized female infant who was born to a mother who had virilizing signs. PATIENT REPORT: The patient had a normally formed phallus and a completely fused scrotum. Baseline as well as stimulated adrenal hormones and testosterone values were in the normal range in the infant. No androgens were given to the mother during pregnancy. Serum 17-OHP, DHEA-S, and testosterone levels were all elevated in the mother. Imaging studies revealed a tumor mass over the left kidney pole. Histologically it was an adrenal tumor. CONCLUSIONS: Although a maternal adrenal tumor is a rare cause of female pseudohermaphroditism, the physician must bear this in mind when confronted with a newborn or infant with 46,XX karyotype and cryptorchidism with a phallic urethra.


Assuntos
Neoplasias das Glândulas Suprarrenais/complicações , Transtornos do Desenvolvimento Sexual/patologia , Uretra/anormalidades , Neoplasias das Glândulas Suprarrenais/cirurgia , Adulto , Transtornos do Desenvolvimento Sexual/diagnóstico , Transtornos do Desenvolvimento Sexual/genética , Feminino , Hormônios/sangue , Humanos , Recém-Nascido , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Uretra/patologia
9.
Invest Clin ; 44(3): 195-207, 2003 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-14552058

RESUMO

Maternal serum screening to identify fetal aneuploidies is now routinely offered during the second trimester of pregnancy in developed countries. The purpose of this prospective study was to assess the value of maternal serum screening between 15 and 20 weeks of gestation to detect fetal aneuploidies and to determine the false positive rate (FPR). Blood samples were collected from 1,062 pregnant women between 15 and 20 weeks of gestation. Samples were assayed for alpha-fetoprotein (AFP), free beta human chorionic gonadotropin (beta-hCG) and unconjugated estriol (uE3). Medians were established at each week from 200 normal, singleton pregnancies. Second trimester risk was calculated using the maternal age and different combinations of AFP, beta-hCG and uE3. Screening results calculated by likelihood ratio to be equal to or greater than 1:270 were considered positive. If the gestational age was confirmed by ultrasonography, genetic counselling and amniocentesis were offered. Ten fetal chromosomal abnormalities were detected with maternal serum screening. Sample's size does not allow a correct detection rate estimation, but false positive rate (FPR) was found to be 6.5%. This FPR has a clinical application. At a cut-off of 1:270, second trimester screening best results were obtained using a combination of all three biochemical markers. These results confirm the efficacy of maternal serum screening for fetal chromosomal abnormalities with a low FPR. The measurement of AFP, beta-hCG and uE3 is an effective prenatal screening test.


Assuntos
Gonadotropina Coriônica Humana Subunidade beta/sangue , Transtornos Cromossômicos/diagnóstico , Estriol/sangue , Diagnóstico Pré-Natal/estatística & dados numéricos , alfa-Fetoproteínas/análise , Adulto , Amniocentese , Biomarcadores , Aberrações Cromossômicas , Transtornos Cromossômicos/sangue , Transtornos Cromossômicos/embriologia , Reações Falso-Positivas , Feminino , Idade Gestacional , Humanos , Gravidez
10.
Int J Pediatr Endocrinol ; 2013(1): 10, 2013 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-23731950

RESUMO

BACKGROUND: It is possible that genes on the X chromosome are expressed differently depending of its parental origin. The objective of this study was to determine the influence of the parental origin of the X-chromosome on phenotypic variability, response to rhGH and on the biochemical profile of TS patients. METHODS: This was a cross-sectional multicenter correlational study carried out over three years in six Latin-American university hospitals. Unrelated 45,X TS patients (n = 93; 18.3 ± 8.5 years )) were evaluated. A subgroup (n = 34) of the patients were prospectively treated with rhGH over two years. DNA profiles of patients and their mothers were compared to determine the parental origin of the retained X-chromosome through 10 polymorphic X-chromosome-STRs. The association with clinical features, biochemical profiles and anthropometric data at the beginning and after two years of rhGH treatment was determined. RESULTS: Seventy two percent of patients retained the maternal X chromosome (Xm). A trend towards significance between maternal height and patients final height (p ≤ 0.07) in 45,Xm subjects was observed. There was no correlation between paternal height and patient height. No differences were detected between both groups in regard to dysmorphic features, classical malformations or increase in the height-SDS after rhGH. There were higher levels of triglycerides, total and LDL cholesterol in patients >20 years who retained the Xm. CONCLUSIONS: The parental origin of the retained X chromosome may influence lipid metabolism in TS patients, but its effect on growth seems to be minimal. No parental-origin-effect on the phenotypic features, associated anomalies and on the growth response to rhGH was found in 45,X TS individuals.

11.
Artigo em Inglês | MEDLINE | ID: mdl-22539924

RESUMO

Protein-folding occurs in several intracellular locations including the endoplasmic reticulum and mitochondria. In normal conditions there is a balance between the levels of unfolded proteins and protein folding machinery. Disruption of homeostasis and an accumulation of unfolded proteins trigger stress responses, or unfolded protein responses (UPR), in these organelles. These pathways signal to increase the folding capacity, inhibit protein import or expression, increase protein degradation, and potentially trigger cell death. Many aging-related neurodegenerative diseases involve the accumulation of misfolded proteins in both the endoplasmic reticulum and mitochondria. The exact participation of the UPRs in the onset of neurodegeneration is unclear, but there is significant evidence for the alteration of these pathways in the endoplasmic reticulum and mitochondria. Here we will discuss the involvement of endoplasmic reticulum and mitochondrial stress and the possible contributions of the UPR in these organelles to the development of two neurodegenerative diseases, Parkinson's disease (PD) and Alzheimer's disease (AD).

13.
Fertil Steril ; 89(2): 458-60, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17531235

RESUMO

A higher incidence of Y-chromosome microdeletions was found on gonadal DNA than on peripheral blood lymphocyte DNA and on streak gonads than on dysgenetic testis in 11 patients with 45,X/46,XY gonadal dysgenesis. It is probable that an association between Y-chromosome microdeletions and severity of the phenotype in 45,X/46,XY patients exists.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Y , Disgenesia Gonadal Mista/genética , Gônadas/metabolismo , DNA/análise , Feminino , Frequência do Gene , Disgenesia Gonadal Mista/metabolismo , Humanos , Masculino , Mosaicismo
14.
Ann Genet ; 46(4): 443-8, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14659779

RESUMO

OBJECTIVE: To delineate the phenotypic spectrum (clinical and gonadal features) from patients with a 45,X/46,X,mar(Y) karyotype based upon of their clinical, histological, cytogenetic and molecular evaluation. SUBJECTS: Three patients with a 45,X/46,X,mar(Y) karyotype. METHODS: Clinical assessment, karyotyping, endocrine evaluation, FISH and PCR analyses of several Y-chromosome loci and direct sequencing of the SRY gene. RESULTS: The patients, two males and one female had varying degrees of impairment of sexual differentiation, with or without testis formation. One patient (reared as female and aged 17 years) had Turner syndrome with bilateral streak gonads. The second patient (2.4 years old) had ambiguous genitalia and presented a dysgenetic testis with a contralateral streak gonad. A third patient (26 years old) had bilateral dysgenetic testes (dysgenetic male pseudohermaphroditism). The ratio of 45,X vs. 46,X,+mar(Y) cells differed between patients and between different tissues. In each case the marker sexual chromosome was identified as a rearranged Y-chromosome (idic(Y)) using FISH and PCR analyses. In all cases the SRY gene was present in all tissues studied. No mutations were identified in this gene in any of the patients. CONCLUSIONS: The extent of male or female differentiation in these patients depends in part on the prevalence, time occurrence, and distribution of the 45,X cell line.


Assuntos
Aberrações Cromossômicas , Cromossomos Humanos X , Cromossomos Humanos Y , Gônadas/anormalidades , Diferenciação Sexual , Adolescente , Pré-Escolar , Transtornos do Desenvolvimento Sexual/genética , Feminino , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Masculino , Fenótipo , Reação em Cadeia da Polimerase , Síndrome de Turner/genética
15.
J Pediatr ; 142(3): 336-40, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12640385

RESUMO

OBJECTIVE: The frequency of Y-chromosome material is high in Turner syndrome (TS), but the ocurrence of gonadoblastoma seems to be low. We performed a study to evaluate whether DNA analysis might be a useful tool in the evaluation of patients with TS. SUBJECTS: Unrelated patients with TS (n = 52) of Venezuelan mestizo ethnic origin were diagnosed by cytogenetic analysis as having TS. METHODS: Clinical assessment, karyotyping, endocrine evaluation, fluorescence in situ hybridization, and polymerase reaction chain analysis of the Y-chromosome loci. RESULTS: We found that 7.69% (4 of 52) patients with TS had Y-chromosome material. A low occurrence of gonadoblastoma was also found (2 of 52 [3.85%]). Two patients showed a 45,X/46,XY karyotype, and gonadoblastoma in the gonadal biopsy specimen was not found. Two patients had no Y chromosome on initial karyotype; they were positive on lymphocyte DNA to Y-sequences specific. Both patients (45,X) had bilateral gonadoblastoma. The four patients with Y-chromosome material in peripheral blood lymphocytes had Y-chromosome sequences on gonadal DNA. Fluorescence in situ hybridization confirmed their Y-chromosome origin. CONCLUSIONS: Our results suggest that the detection of Y-chromosome material should be carried out in all patients with TS and not be limited to patients with TS with cytogenetically identifiable Y chromosome and/or virilization.


Assuntos
Cromossomos Humanos Y/genética , Síndrome de Turner/genética , Criança , Análise Citogenética , Feminino , Gonadoblastoma/complicações , Gonadoblastoma/genética , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Mosaicismo , Neoplasias Ovarianas/complicações , Neoplasias Ovarianas/genética , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Síndrome de Turner/complicações , Síndrome de Turner/diagnóstico
16.
Invest. clín ; Invest. clín;50(1): 55-63, mar. 2009. tab, graf
Artigo em Espanhol | LILACS | ID: lil-518698

RESUMO

Las mutaciones en el oncogén K-ras son comunes en cáncer colo-rectal, afectan el comportamiento biológico y podrían influir en la susceptibilidad terapéutica en estos tumores. El objetivo de este trabajo fue identificar los tipos de mutación K-ras observados en pacientes referidos con cáncer colo-rectal y relacionarlos con el grado de diferenciación histológica y con el estadio clínico. Se obtuvo ADN genómico tanto de tejido tumoral incluido en parafina, como de tejido fresco. Se amplificó el gen K-ras a través de la reacción en cadena de la polimerasa (RCP) y se digirieron los fragmentos amplificados con enzimas de restricción, por último se obtuvieron datos clínicos e histopatológicos de las historias clínicas. Se encontraron mutaciones en los codones 12 y 13 del oncogén K-ras en el 23,33% de los pacientes. De estos 28,57% en el codón 12, en el codón 13 se encontró un 57,14% y 14,29% para ambos codones. Fueron más frecuentes en el hemicolon izquierdo con 78,57% y según la clasificación histológica en los adenocarcinomas bien diferenciados (58,70%) y en los mucinosos (28,57%). Las mutaciones identificadas fueron mas frecuentes en estadios avanzados C2 de la clasificación de Dukes`. El análisis molecular del oncogén K-ras permitió evidenciar mutaciones que sirven como parámetro diagnóstico y pronóstico en los tumores colo-rectales. La frecuencia de mutaciones encontradas en este trabajo es similar a algunas de las reportadas a nivel mundial, sin embargo difieren en el tipo de mutación mas frecuente, que en nuestro medio fue la mutación del codón 13 del gen con más de un 50%.


Mutations in the K-ras oncogene are common in colo-rectal cancer, which affect the biological behaviour and may influence the susceptibility to therapy in these tumors. The objective of this work was to identify the types of K-ras mutations observed in referred patients with colo-rectal cancer and to relate them to their degree of histological differentiation and clinical stage. Histopathological and clinical data were obtained from medical records. DNA was obtained from both, fresh tissue and tumor tissue embedded in paraffin. The K-ras gene was amplified through the polymerase chain reaction (PCR) and the amplified fragments were digested with restriction enzymes. We found mutations in codons 12 and 13 of the K-ras oncogene in 23.33% of patients. Of these, 28.57% were located at codon 12, 57.14% were at codon 13 and 14.29% at both codons. They were more frequent in tumors located in the left hemicolon and, according to their histological type, were more frequent in well differentiated adenocarcinomas (58.70%) and in mucinous (28.57%). The identified mutations were more frequent in advanced stages (C2) of Dukes’ classification. The molecular analysis of the K-ras oncogene made mutations evident, which could be useful in the diagnosis and prognosis of colorectal tumors. The frequency of mutations found in this work is similar to some of those reported worldwide; however, they differ in the more frequent type of mutation, which, in our study, was located at codon 13 in more than 50% of the cases.


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Adenocarcinoma/patologia , Genes ras , Mutação , Neoplasias do Colo/diagnóstico
17.
Rev. venez. endocrinol. metab ; 7(1): 26-34, feb. 2009. ilus, tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-631353

RESUMO

Objetivos. La deleción (GHRd3) o inserción (GHRfl) del exón 3 es un polimorfismo común en el gen del receptor de la hormona de crecimiento (GHR) en los seres humanos. La presencia del alelo GHRd3 se ha asociado con el grado de respuesta de terapia con Hormona de Crecimiento Recombinante Humana (rhGH). El objetivo de este estudio fue determinar las frecuencias alélicas y genotípicas de este polimorfismo en un grupo de 69 niños venezolanos con talla baja que estaban recibiendo rhGH. Métodos. Se extrajo DNA a través de la técnica del método combinado Fenol/Sevag e Inorgánica. Se determinó el genotipo del exón 3 del gen GHR usando tanto PCR- monoplex como PCR-multiplex. Resultados. Entre los pacientes con talla baja la frecuencia genotípica se distribuyó de la siguiente manera: GHRfl/GHRfl (55%) GHRfl/GHRd3 (35%) y GHRd3/GHRd3 (10%) y la frecuencia alélica fue de 0,27 para GHRd3 y 0,73 para GHRfl. Para el grupo testigo la frecuencia genotípica se distribuyo así: GHRfl/GHRfl (56%), GHRfl/ GHRd3 (30%) y GHRd3/GHRd3 (14%) y la frecuencia alélica era de 0,29 para GHRd3 y 0,71 para GHRfl. Las características clínicas basales de los pacientes con talla baja eran similares entre los diferentes genotipos encontrados en el grupo de estudio. Conclusiones. La proporción del genotipo y los alelos del gen GHR fueron similares entre el grupo testigo y los pacientes con talla baja, lo que traduce que la etiología de la talla baja no obedece a este polimorfismo.


Objective. The deletion (GHRd3) or insertion (GHRfl) of exon 3 is a common polymorphism in the receptor growth hormone gene (GHR) in humans. The presence of the allele GHRd3 has been associated with the degree of responsiveness to therapy with recombinant human Growth Hormone (rhGH). The aim of this study was to determine the genotypic and allele frequencies of this polymorphism in a group of 69 Venezuelan children with short stature who were receiving rhGH. Methods. Genomic DNA was extracted from blood lymphocytes using combined method Fenol/SEVAG + Salting out. The GHR-exon 3 was genotyped using both PCR monoplex and multiplex assays. Results. Among patients with short stature, genotype frequency was distributed as follows: GHRfl/GHRfl (55%), GHRfl/GHRd3 (35%) and GHRd3/GHRd3 (10%) and allele frequency for GHRd3 and GHRfl was 0.27 and 0.73, respectively. For the control group, genotype frequency was distributed as follows: GHRfl/GHRfl (56%), GHRfl/GHRd3 (30%) and GHRd3/GHRd3 (14%) and allele frequency for GHRd3 and GHRfl was 0.29 and 0.71, respectively. The baseline clinical features of patients with short stature were similar among different genotypes found in the study group. Conclusions. The proportion of genotype and allele of the GHR gene were similar between the control group and patients with short stature, which translates that the etiology of short stature is not due to this polymorphism.

18.
Invest. clín ; Invest. clín;44(3): 195-207, sept. 2003. tab
Artigo em Espanhol | LILACS | ID: lil-361135

RESUMO

El cribado sérico materno para identificar aneuploidías fetales se ofrece rutinariamente durante el segundo trimestre del embarazo en países desarrollados. El propósito de este estudio prospectivo fue evaluar la utilidad del cribado sérico materno entre las 15 y 20 semanas de gestación para detectar aneuploidías fetales y determinar la tasa del falso positivo (TFP). Se tomaron muestras de sangre de 1.062 mujeres entre 15 y 20 semanas de gestación. Se determinaron las concentraciones séricas de alfafetoproteína (AFP), fracción beta libre de la gonadotrofina coriónica humana (ß-hCG) y el estriol no conjugado (uE3). Se establecieron las medianas para cada semana de gestación a partir de 200 embarazos simples cromosómicamente normales. Se calculó el riesgo para el segundo trimestre del embarazo usando la edad materna y diferentes combinaciones de AFP, ß-HCG y uE3. Se consideraron como positivos los resultados del cribado calculados por la relación de verosimilitud que eran iguales o mayores a 1:270. Si la edad gestacional era confirmada por ultrasonido, se ofrecía asesoramiento genético y amniocentesis. Se detectaron diez anormalidades cromosómicas fetales con el cribado sérico materno. El tamaño de la muestra no permite estimar una tasa de deteccion correcta, pero se encontró una TFP de 6,5 por ciento. Esta TFP tiene aplicación clínica. A un índice de corte de 1:270, los mejores resultados del cribado sérico materno fueron obtenidos usando la combinación de los tres marcadores bioquímicos analizados. Estos resultados confirman la eficacia del cribado sérico materno para las anormalidades cromosómicas fetales con una TFP baja. La medición de Afp. ß-hCG y uE3 es una prueba prenatal efectiva.


Assuntos
Humanos , Adulto , Feminino , Gravidez , Amniocentese , Aberrações Cromossômicas , Peneiramento de Líquidos , Medicina Clínica , Pesquisa , Venezuela
19.
Invest. clín ; Invest. clín;39(4): 273-92, dic. 1998. tab
Artigo em Espanhol | LILACS | ID: lil-251939

RESUMO

Las anormalidades de la Diferenciación Sexual (ADS) representan un conjunto de enfermedades, heterogéneas tanto en su etiopatogenia como en sus manifestaciones clínicas. Con la finalidad de caracterizar y analizar los aspectos epidemiológicos, clínicos, endocrinos y genéticos de los pacientes con ADS que consultaron a UGM-LUZ en el período 1971-1996, se evaluaron todas las familias que tuvieron al menos un afectado, estableciendose criterios diagnósticos estrictos para cada entidad. A cada paciente se les practicó estudio citogenético en sangre periférica, determinaciones hormonales, evaluaciones radioecodiagnósticas y estudios anatomohistopatológicos según cada caso en particular. De 391 familias 489 pacientes consultaron por presentar ADS, lo que representa el 5,4 por ciento del total de los pacientes que consultaron a UGM-LUZ en el período señalado. Se detectaron 214 (50 por ciento) pacientes con diagnóstico definitivo de ADS al cumplir los criterios de inclusión establecidos, distribuidos de la siguiente manera: 139 con Anomalías de los cromosomas sexuales; 36 con hiperplasia adrenal congénita; 21 con síndrome de insensibilidad androgénica completa; 14 con disgenesia gonadal mixta y 4 con hermafroditismo verdadero. Se diagnósticaron 183 pacientes (42,7 por ciento) con pseudohermafroditismo masculino y 17 (3,9 por ciento) con pseudohermafroditismo femenino, al no llenar los criterios diagnósticos establecidos. 15 (3,4 por ciento) pacientes presentaron ADS asociada a un cuadro polimalformativo. Las ADS representan una causa importante de morbilidad en UGM-LUZ. Estas, por ser entidades nosológicas complejas necesitan de la integración multidisciplinaria del equipo de salud


Assuntos
Humanos , Masculino , Feminino , Cromossomos/classificação , Citogenética/classificação , Diferenciação Sexual/genética , Transtornos do Desenvolvimento Sexual/complicações , Gônadas , Sexo , Venezuela
20.
Invest. clín ; Invest. clín;37(3): 167-75, sept. 1996. tab
Artigo em Espanhol | LILACS | ID: lil-199237

RESUMO

La Leucemia Mieloide Crónica (LMC), es una enfermedad clonal de la médula ósea, que se caracteriza por la presencia del cromosoma filadelfia (Ph). Anomalías adicionales al cromosoma Ph han sido señaladas durante la evolución de la LMC. En este trabajo se trata de evidenciar las anomalías citogenéticas durante la evolución de la LMC en nuestra región y la relación con su evolución clínica. Se recibieron 55 muestras de médula ósea, 81,8 por ciento (45/55) en fase crónica (FC), 12,7 por ciento en fase acelerada (FA) y 5,4 por ciento (4/55) en crisis blástica (CB). A 12/45 pacientes en fase crónica se les repitió el cariotipo por lo menos una vez al año durante la evolución de su enfermedad, 9 de los 12 pacientes evolucionados presentaron el cromosoma Ph como única anomalía al momento del diagnóstico, los 3 restantes presentaron anomalías adicionales diferentes al cromosoma Ph. 4/9 presentaron anomalías durante la evolución de la enfermedad, pasando a la FA ó CB entre los 4 a 8 meses posteriores al hallazgo. 7 de los 10 pacientes referidos en FA ó CB presentaron anomalías adicionales al cromosoma Ph. Se hace evidente una vez más la necesidad del estudio cromosómico en todo paciente con LMC, por lo menos una vez al año, para poder detectar las anomalías cromosómicas adicionales al cromosoma Ph durante la evolución de la misma, para lograr mejor control terapéutico de la enfermedad


Assuntos
Masculino , Feminino , Cariotipagem , Leucemia Mieloide/diagnóstico
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