ABSTRACT
There are two major forms of the BCR/ABL fusion gene, involving ABL exon 2, but including different exons of BCR gene. The transcripts b2a2 or b3a2 code for a p210 protein. Another fusion gene leads to the expression of an e1a2 transcript, which codes for a p190 protein. Another, less common fusion gene is c3a2[e19a2], which encodes a p230 protein. The incidence of one or the other rearrangement in chronic myeloid leukaemia (CML) patients varies in different reported series. This study was designed to determine the frequency of coexpresion of the p210, p190 and p230 transcripts in 250 Mexican patients with CML. We performed nested and multiplex reverse transcriptase polymerase chain reaction (RT-PCR) on bone marrow samples from adult patients and found that all cases were positive for some type of BCR/ABL rearrangement. In 226 (90.4%) patients it was p210, while the remaining 9.6% showed coexpression or one of the transcripts of p190/p210/p230. In 7% of patients with p210 expression there are both isoforms (b3a2/b2a2), presumably the result of alternative splicing. The rate of coexpression of the p190/p210 transcripts was 5%, which is much lower than in other reports. This may be due to the technical factors. These patients had high platelet counts, marked splenomegaly and chromosomal abnormalities in addition to Ph'. Other types of coexpression seen were p210/p230 and p190/p210/p230, in patients with high-risk clinical factors. Our study confirms the occurrence of coexpression of different BCR/ABL transcripts, although the rate (9.6%) was much lower than has been reported in other populations. This may reflect either the sensitivity of the detection techniques used or the possibility of genetic differences between the populations studied. Coexpression may be due to alternative splicing or to phenotypic variation, with clinical courses different from classical CML.
Subject(s)
Fusion Proteins, bcr-abl/genetics , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics , Adolescent , Adult , Aged , Cytogenetic Analysis , Exons , Female , Gene Rearrangement , Genetic Variation , Humans , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/epidemiology , Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology , Male , Mexico/epidemiology , Middle Aged , Phenotype , Protein Isoforms/analysis , Protein Isoforms/genetics , RNA, Messenger/analysis , RNA, Messenger/genetics , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
A study was undertaken to ascertain the effect of [glass-and-silver fillings ionomer] on the pulp tissue at different times (15, 30 and 60 days). For that purpose, 34 premolars were evaluated, on which a basic coating of calcium hydroxide was applied previous to their obturation with an ionomer cement (Ketac Silver). Dental organs were divided in four groups, namely: untreated control, and three groups of 10 premolars which were extracted after 15, 30 and 60 days. Results yielded by this research suggest that applying a calcium hydroxide coating is not enough to prevent the toxic effect of the glass ionomer on the pulp.
Subject(s)
Cermet Cements/adverse effects , Dental Pulp Capping , Dental Pulp/drug effects , Root Canal Filling Materials/adverse effects , Adolescent , Adult , Bicuspid , Calcium Hydroxide , Humans , SilverABSTRACT
Se llevó a cabo un estudio con el propósito de conocer el efecto que causa el ionómero de vidrio con limadura de plata sobre el tejido pulpar a diferentes tiempos (15, 30 y 60 días); para esto se valoraron 34 premolares a los que se les realizaron cavidades de V clase y se les aplicó una base de hidróxido de calcio para después obturarlos con un cemento a base de ionómero (Ketac Silver). Los órganos dentarios se dividieron en cuatro grupos: control sin tratamiento, y tres grupos de 10 premolares que se extrajeron a los 15, 30 y 60 días. Los resultados que arrojó esta investigación sugieren que colocar una capa de hidróxido de calcio no es suficiente para impedir el efecto tóxico del ionómero de vidrio sobre la pulpa
