Study of the polymorphism rs3025058 of the MMP-3 gene and risk of pelvic organ prolapse in Brazilian women.

OBJECTIVE: To analyze the polymorphism -1171 5A / 6A rs3025058 of the MMP-3 gene and the risk for pelvic organ prolapse (POP). STUDY DESIGN: This is a cohort study. All patients attended the Urogynecology and Vaginal Surgery Section of the FMABC, from 2014 to 2016 and they were randomly recruited by the researchers at the first medical appointment. We selected 112 patients with symptomatic POPs and 180 patients with normal pelvic floors. The single nucleotide polymorphism (SNP) 5A / 6A of MMP-3 was determined by polymerase chain reaction (PCR) and analysis of the restriction fragments in both groups. Chi-squared test was used to compare the frequencies of polymorphisms between the groups. For those characteristics with statistical relevance, the crude odds ratio (OR) and its respective 95% confidence intervals were calculated; and, by logistic regression, were adjusted for each of the other characteristics, obtaining the adjusted OR. Hardy-Weinberg gene balance was determined using Pearson's Chi-squared test. Values of p < 0.05 were considered statistically significant. RESULTS: Logistic regression of factors associated with genital prolapse showed that age (adjusted OR = 11.89, 95% CI, 3.53-40) and home delivery (adjusted OR = 9.645, 95% CI, 3.35-27.7) remained risk factors for genital prolapse in the sample studied. There was no statistically significant difference between the groups in the distribution of genotypes, even after calculating the contribution of the 5A recessive allele in the aggregated genotypes (5A / 5A + 5A / 6A). CONCLUSION: The polymorphism -1171 5A / 6A rs3025058 of the MMP-3 gene was not associated with the risk for POP. Age and home delivery were significantly associated with increased risk for the disease.

Cellular spelunking: exploring adipocyte caveolae.

It has been known for decades that the adipocyte cell surface is particularly rich in small invaginations we now know to be caveolae. These structures are common to many cell types but are not ubiquitous. They have generated considerable curiosity, as manifested by the numerous publications on the topic that describe various, sometimes contradictory, caveolae functions. Here, we review the field from an "adipocentric" point of view and suggest that caveolae may have a function of particular use for the fat cell, namely the modulation of fatty acid flux across the plasma membrane. Other functions for adipocyte caveolae that have been postulated include participation in signal transduction and membrane trafficking pathways, and it will require further experimental scrutiny to resolve controversies surrounding these possible activities.

Immunopurification and characterization of rat adipocyte caveolae suggest their dissociation from insulin signaling.

Adipocytes play an important role in the insulin-dependent regulation of organismal fuel metabolism and express caveolae at levels as high or higher than any other cell type. Recently, a link between insulin signaling and caveolae has been suggested; nevertheless, adipocyte caveolae have been the subject of relatively few studies, and their contents have been minimally characterized. With the aid of a new monoclonal antibody, we developed a rapid procedure for the immunoisolation of caveolae derived from the plasma membrane of adipocytes, and we characterized their protein content. We find that immunopurified adipocyte caveolae have a relatively limited protein composition, and they lack the raft protein, flotillin, and insulin receptors. Immunogold labeling and electron microscopy of the adipocyte plasma membrane confirmed the lack of insulin receptors in caveolae. In addition to caveolins, the structural components of caveolae, their major protein constituents, are the semicarbazide-sensitive amine oxidase and the scavenger lipoprotein receptor CD36. The results are consistent with a role for caveolae in lipid flux in and of adipocytes.

Two types of ribosomal RNA genes in hybrid Trypanosoma cruzi strains.

Trypanosoma cruzi isolates can be divided into two major phylogenetic lineages-T. cruzi I and T. cruzi II. The population structure is predominantly clonal, with sexuality having no or limited influence on the evolution of the parasite. Isoenzymes and nuclear gene sequences have provided evidence that some T. cruzi strains are hybrids. Previous work of our group has shown that the putative hybrid strains designated as group 1/2 contain two types of rDNA units, corresponding to those found in T. cruzi I and T. cruzi II. In this study, the presence and transcription of the two types of ribosomal RNA (rRNA) cistrons were investigated in epimastigotes, metacyclic and tissue culture trypomastigotes of group 1/2 isolates. PCR and RT-PCR assays indicate that both types of cistrons are present in group 1/2 strains, but only type-2 genes are transcribed in all developmental stages. The structure of the promoter regions of group 1/2 was compared to reference T. cruzi I and T. cruzi II strains. In all cases, the transcription start point was mapped to a conserved A residue located approximately 1800 bp upstream the 18S rRNA gene. The distribution of rDNA clusters in chromosomal bands of group 1/2 was evaluated by pulsed-field gel electrophoresis (PFGE). The majority of type-2 rDNA genes are localized in a 1.5 Mbp band, whereas type-1 cistrons are mostly concentrated in a 1.1 Mbp band. The structural and functional studies of group 1/2 ribosomal cistrons described here may shed light on the evolutionary processes that took place during the generation of such hybrid organisms.

Biological parameters and molecular markers of clone CL brener - the reference organism of the Trypanosoma cruzi genome project

Clone CL Brener is the reference organism used in the Trypanosma cruzi Genome Project. Some biological paramenters of CL Brener were determined: (a) the doubling time of epimastigote forms cultured in liver infusion-tryptose (LIT) medium at 28ºC is 58ñ13 hr; (b) differentiation of epimastigotes to metacyclic trypomastigotes is obtained by incubation in LIT-20 per cent Grace's medium; (c) trypomastigotes infect mammalian cultured cells and perform the complete intracellular cycle at 33 and 37ºC; (c) blood forms are highly infective to mice; (e) blood forms are susceptible to nifurtimox and benznidazole. The molecular typing of CL Brener has been determined: (a) isoenzymatic profiles are characteristic of zymodeme ZB; (b) PCR amplification of a 24 alpha ribosomal RNA sequence indicates it belongs to T. cruzi lineage 1; (c) schizodeme, randomly amplified polymorphic DNA (RAPD) and DNA fingerprinting analyses were performed.

Molecular approaches to diagnosis of Chagas' disease: use of defined antigens and a target ribosomal RNA sequence

We evaluated the performance of two defined antigens in the serological diagnosis of Chagas' disease. One of them is a recombinant protein named B13 isolated from a genomic library of Trypanosoma cruzi in the expression vector lambda gtll. We show that the gene corresponding to B13 is conserved in the evolutive stages of the two ®polar® strains of T. cruzi. The protein epitopes cloned in B13 are represented in 140 kDa, 116 kDa and 35 kDa polypeptides of trypomastigotes. The other antigen chosen for serodiagnosis is a lipopeptidophosphoglycan (LPPG). This glycoconjugate is also widely distributed in T. cruzi strains. The use of a rabbit serum to LPPG allowed the demonstration that this molecule bears epitopes in common to LPPG-like components and to 80-90 kDa glycoproteins of trypomastigotes. Both B13 and LPPG were evaluated in serodiagnosis by ELISA and RIA using a panel of normal human, Chagasic and Leishmaniasis sera. It was observed that B13 presents high sensitivity and specificity for Chagasic sera. For LPPG it was also concluded that this reagent discriminates between individuals infected and non-infected with T. cruzi. A heterogeneity in the level of antibodies to LPPG in Chagasic patients was detected. No correlation was found between the clinical form of Chagas' disease and the preferential reactivity to B13 or LPPG. We also report preliminary studies towards the characterization of a 100 bp sequence of the 24S alpha rRNA as a target for DNA-based detection systems for diagnosis. We show that polymerase chain reaction of total DNA of different trypanosomatids lead to the specific amplification of a 100 bp fragment only for T. cruzi. Northern blots confirmed the presence of the target region in the mature 24S alpha rRNA. Titration experiments based on the direct amplification of RNA with Taq DNA polymerase allowed the detection of 50 parasites. Studies are in progress to increase the sensitivity of the proposed system