RESUMO
BACKGROUND AND OBJECTIVE: Gingival overgrowth is a prominent side effect of cyclosporine (CsA) therapy in renal transplant patients. Although the exact mechanism by which this drug induces gingival overgrowth is uncertain, marked variations in individual susceptibility to this drug suggest a genetic predisposition. Studies have shown that genetic variation (polymorphism) in the trinucleotide cytosine-adenine- guanine (CAG) sequence in exon 1 of the androgen receptor (AR) gene is related to altered activity of the AR as a transcription factor. However, the relationship between the length of the CAG repeat and gingival overgrowth has not yet been studied. The present study was carried out to determine whether there is an association between CsA-induced gingival overgrowth and the length of the CAG repeats in the AR gene. MATERIAL AND METHODS: Genomic DNA samples were prepared from the blood of 50 renal transplant patients with CsA-induced gingival overgrowth and from the blood of 100 renal transplant patients on CsA with no gingival overgrowth. RESULTS: The difference in allele distribution among the subjects with gingival overgrowth and control samples was statistically significant (p = 0.001). CONCLUSION: The findings suggest a link between CsA7induced gingival overgrowth and a smaller size of CAG repeat in the AR gene.
Assuntos
Adenina , Ciclosporina/efeitos adversos , Citosina , Crescimento Excessivo da Gengiva/induzido quimicamente , Guanina , Imunossupressores/efeitos adversos , Polimorfismo Genético/genética , Receptores Androgênicos/genética , Sequências Repetitivas de Ácido Nucleico/genética , Adulto , Alelos , Pareamento de Bases , Estudos Transversais , Éxons/genética , Feminino , Frequência do Gene/genética , Variação Genética/genética , Crescimento Excessivo da Gengiva/genética , Humanos , Transplante de Rim , Masculino , Adulto JovemRESUMO
The influence of solutions of ascorbic acid, thiamine, L-arginine, and L-gtutamic acid on egg hatch, juvenile survival, and development and reproduction of Meloidogyne incognita in susceptible and resistant tomatoes was studied. Maximum inhibition of egg hatch occurred at 2,000, 4,000, and 2,000 ppm for ascorbic acid, L-arginine, and L-glutamic acid, respectively. Larval survival was significantly reduced by concentrations of 2,000 ppm ascorbic acid and 1,000 ppm of L-arginine. Maximum inhibition of egg hatch and mortality of juveniles was achieved at a concentration of 4,000 ppm of ascorbic acid and L-arginine. L-glutamic acid and thiamine had respective moderate and minimal toxic effects. Foliar sprays of ascorbic acid, L-arginine, or L-glutamic acid suppressed the numbers of root galls, females, and egg masses on the susceptible tomato cultivar Tropic. Ascorbic acid and L-arginine had highly significant effects when applied to foliage before inoculation with nematodes. Thiamine had little effect. All sprays suppressed the numbers of root galls and females in roots of the resistant cultivar VFN8 when treatments were applied before inoculation. They were not, however, effective as post-inoculation treatments. Growth of a susceptible cultivar was improved by post-inoculation and pre-inoculation treatments when compared with the control plants which had neither nematode infection nor chemical treatment. No positive growth response to chemical treatment was seen in resistant control plants.
