RESUMEN
The aim of this study was to determine the prevalence of polymorphisms in the glutathione S-transferase genes GSTM1 and GSTT1 in patients with lens opacity (cataract). Peripheral blood samples were obtained from male and female patients (N = 23) with cataract. The GSTM1 and GSTT1 polymorphic regions were amplified by polymerase chain reaction, and the amplification products were electrophoresed on a 2% agarose gel. The obtained bands were by staining with ethidium bromide. The results were compared by a chi-square test using the BioEstat software (v.5.0). The frequencies of the GSTM1- and GSTT1-null genotypes were higher than those of the GSTM1- and GSTT1-present genotypes. The frequency of GSTT1-null genotypes was approximately 1.7 times higher than that of GSTM1, which was a statistically significant difference (P = 0.0019). Although a consensus remains to be reached on the correlation between genetic polymorphisms in GSTs and cataract susceptibility, the observations from most scientific studies are similar to those reported in this study. Thus, we conclude that the absence of these genes, particularly GSTT1, is correlated with the development of lens opacity.
Asunto(s)
Catarata/diagnóstico , Catarata/genética , Predisposición Genética a la Enfermedad , Glutatión Transferasa/genética , Polimorfismo Genético , Adulto , Catarata/patología , Femenino , Expresión Génica , Frecuencia de los Genes , Glutatión Transferasa/deficiencia , Humanos , Cristalino/metabolismo , Cristalino/patología , Masculino , Persona de Mediana EdadRESUMEN
The first reports about pterygium date back to Hippocrates, and this disease still threatens vision health around the world. Pterygium is a formation of fibrous tissue consisting of highly vascularized epithelial and subepithelial tissue that grows excessively and with an abnormal shape on the cornea. Many physical and biological factors are associated with the pathogenesis of pterygium, including heat, dust, and other particles in the atmosphere, and immunological mechanisms, mechanisms involving extracellular matrix reorganization, growth factors, cytokines, apoptosis, and angiogenesis. The aim of this study was to further investigate the association between polymorphisms in GSTM1 and the formation of pterygium. We collected peripheral blood samples from 90 patients diagnosed with pterygium and from 23 subjects with-out the disease in order to perform molecular analysis of the GSTM1 gene. Subjects with one or two copies of the GSTM1 allele had a normal genotype while those without any copies of the allele had a null geno-type. The chi-square test or the Fisher exact test was performed in order to investigate possible associations between the molecular analysis and the risk of pterygium. A significant difference between the frequency of the GSTM1-null genotype in patient and control groups was identified. However, sub-group analysis found that the GSTM1-null genotype was statistically significant in men, but not in women, and in Caucasians, but not in Brown or Black groups. Furthermore, the GSTM1-null geno-type was not related to any of the risk factors analyzed: cases in family, occupational exposure, smoking, hypertension, and diabetes.
Asunto(s)
Glutatión Transferasa/genética , Polimorfismo Genético , Pterigion/etnología , Pterigion/genética , Población Blanca/genética , Brasil/etnología , Estudios de Casos y Controles , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Factores SexualesRESUMEN
Pterygium is an inflammatory and degenerative ocular surface disease in which the conjunctiva on the cornea grows to form a fibrous tissue in the shape of a triangle. The disorder may be characterized by cell proliferation, inflammatory processes, fibrosis, angiogenesis, and destruction of the extracellular matrix. The anomaly is considered a degenerative eye disease and is erroneously confused with cataract. It displays similar features to those of tumors, such as local invasion, metaplasia of epithelial cells, presence of oncogenic viruses (human papilloma virus), inactivation of tumor suppressor genes (e.g., p53), and loss of heterozygosity. The treatment of pterygium is based on factors such as the evolution and progression of the disease, risk factors, symptoms, and patient age. Considerations about the best technique for the surgical removal of pterygium remain controversial, and complications and recurrence are very common. The development of new surgical techniques and adjuvant drugs is thus necessary. This study aims to analyze and compare the frequency of the GSTT1 genotypes in relation to pterygium through statistical analyzes in order to build a genotypic profile for the Replicon patients. The genotypic profile of the GSTT1-null polymorphism in Goiânia showed no significant difference when the frequency of the null genotype was compared between the control and experimental groups. The null genotype was more frequent in the population studied. Furthermore, the GSTT1 genotype was not related to the analyzed risk factors for pterygium, namely gender, ethnicity, family history, occupational exposure, smoking, hypertension, and diabetes.
Asunto(s)
Glutatión Transferasa/genética , Polimorfismo Genético , Pterigion/genética , Brasil , Estudios de Casos y Controles , Diagnóstico Diferencial , Femenino , Estudios de Asociación Genética , Genotipo , Humanos , Masculino , Pterigion/etnología , Factores de RiesgoRESUMEN
The authors studied experimentally the electromagnetic pulsing field effects in an experimental model in rats, for evaluation of the velocity of consolidation of tibial and fibular fractures. The animals were followed for a period of three weeks under continuous stimulation and there were done radiological evaluation weekly and histological study at the end of the study. There were no histological, clinical or radiological differences between the group of rats submitted to electromagnetic pulsing fields and the control group.