Protease inhibitor effects on prevalence of bacterial vaginosis and human papillomavirus-related lesions.

AIM: Antiretrovirals of the protease inhibitor (PI) class tend to achieve low concentrations in biological fluids. This study aimed to analyze possible changes in the vaginal microbiome and frequency of cervical human papillomavirus (HPV)-DNA and HPV-related lesions associated with the use of PI in antiretroviral therapy (ART). METHODS: Eighty-eight women with human immunodeficiency virus infection were divided in two groups: ART with PI and without PI. All the participants underwent anamnesis with demographic data collection. The total DNA, used as the template in the polymerase chain reaction-based assays for the detection of HPV-DNA, was extracted from cervical samples during cervical cytopathology. RESULTS: There were no differences between the groups with respect to HPV-related lesions. Despite the higher prevalence of bacterial vaginosis (BV) in the PI group (33.96% vs 17.14%), the difference was insignificant when considering all women (P = 0.066). When women with a detectable viral load and a CD4+ T-cell count <200 were excluded in both groups, BV was found to be more prevalent in the PI group (odds ratio, 3.349; 95% confidence interval, 1.113-11.41, P = 0.049). No associations were found between BV and age, condom use, cervical HPV, time with current ART regimen, unprotected receptive anal intercourse and cervical HPV-related lesions. CONCLUSION: The use of PI did not alter the frequencies of HPV-DNA and HPV-related lesions. However, an increased frequency of BV was found in women using PI after excluding women with a detectable viral load and a CD4+ T-cell count of <200.

Is higher prevalence of cervical intraepithelial neoplasia in women with lupus due to immunosuppression?

BACKGROUND: Cervical cancer (CC) is still the second in prevalence and mortality among women. In spite of previously observed higher incidence of cervical dysplasia among systemic lupus erythematosus (SLE) patients, few studies have considered the influence of classic risk factors and the use of immunosuppressors (IM). OBJECTIVES: To study cervical dysplasia prevalence among SLE patients submitted or not to immunosuppression and to evaluate its association with classic risk factors. METHODS: A group of 171 SLE patients including 87 who were receiving IM continuously for at least 1 year was compared with 222 age- and sociocultural-paired women (control group) submitted to routine cervical cytopathology. Statistical methods included univariate and multivariate analysis, besides parametric and nonparametric tests. RESULTS: The prevalence of atypical squamous cells of undetermined significance, low-grade and high-grade intraepithelial lesions were significantly increased in SLE patients (12.8%, 5.8%, and 3.5%, respectively) compared with controls (3.1%, 0.9%, and none, respectively, P = 0.0001), although they presented significantly fewer classic risk factors for CC. Multivariate analysis showed that SLE women had a 7-fold higher prevalence of cervical dysplasia (OR: 7.23, 95% IC: 3.40-15.38) and an 11-fold higher prevalence of premalignant cervical dysplasia (OR: 11.36, 95% IC: 2.57-50.10) compared with controls. SLE patients with long-term use of IM presented even higher prevalence of low-grade and high-grade intraepithelial lesions in comparison with those without long-term use of these agents (68.7% vs. 31.1%, P = 0.03). CONCLUSIONS: This study provides evidence that even though not presenting the classic risk factors for CC, SLE patients, especially those exposed to long-term immunosuppression, have increased chances of presenting more premalignant lesions than the general population and they probably need to follow a more stringent CC prevention program.

Engineering thermal stability in RNA phage capsids via disulphide bonds.

The RNA bacteriophages, a group that includes phages Qbeta and MS2, have a number of potential bionanotechnological applications, including cell specific drug delivery and as substrates for the formation of novel materials. Despite extensive sequence identity between their coat protein subunits, and an almost identical three-dimensional fold, Qbeta and MS2 capsids have dramatically different thermal stabilities. The increased stability of Qbeta has been correlated with the inter-subunit disulphide bonds present in that capsid and not present in MS2. We have tested this hypothesis directly using mass spectrometry. Analysis of the dissociated coat protein subunits suggests that inter-molecular disulphides are formed at the capsid five-fold but may not be at the three-fold axes. This conclusion has been tested by engineering disulphide cross-links into either the five-fold or three-fold positions of the recombinant MS2 capsid. Five-fold cross-linking results in a mutant with stability properties similar to those of Qbeta. Three-fold cross-linking results in a mutant unable to assemble T = 3 shells, implying that five-fold structures are on pathway to capsid assembly in these phages. The results demonstrate how it is possible to redesign the physical properties of phage shells and may be of general relevance to future applications of viruses and virus-like particles.

Frequencies of GSTM1, GSTT1, and GSTP1 polymorphisms in a Brazilian population.

The glutathione S-transferase (GST) family of enzymes has a vital role in phase II of biotransformation of environmental carcinogens, pollutants, drugs and other xenobiotics. GSTs are polymorphic, with the type and frequency of polymorphism being ethnic dependent. Polymorphisms in GST genes have been shown to be associated with susceptibility to disease and disease outcome. We determined the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms in 591 volunteers who had been residents of Rio de Janeiro for at least six months. Blood was collected and DNA extracted by proteinase K/SDS digestion. Information about social habits and health problems was also recorded. GSTM1 and GSTT1 polymorphisms were analyzed by a PCR-Multiplex procedure, whereas GSTP1 polymorphism was analyzed by PCR-RFLP. We found that 42.1% (48.9% of whites and 34.2% of non-whites) of the individuals had the GSTM1 null genotype, whereas 25.4% (25.1% of whites and 25.7% of non-whites) had the GSTT1 null genotype. The genotypic distribution of GSTP1 was 49.7% I/I, 38.1% I/V, and 12.2% V/V, whereas the allelic frequencies were 0.69 for the Ile allele, and 0.31 for the Val allele. The frequencies of GST polymorphisms in this Brazilian population were found to be different from those observed in other populations, particularly of other South American countries.

Presence of Helicobacter pylori in supragingival dental plaque of individuals with periodontal disease and upper gastric diseases.

BACKGROUND: Helicobacter pylori is a Gram-negative microorganism which is able to colonize the gastric mucosa and is associated with peptic ulcer, gastric carcinoma, and gastric mucosa-associated lymphoid tissue lymphoma. Several studies have detected this bacterium in the oral cavity, suggesting it as a potential reservoir. The aim of this study was to investigate the presence of H. pylori in the oral cavity of individuals with periodontal disease and gastric diseases. METHODS: 115 individuals, with mean age 49.6 (±5.8) years, were divided in 4 groups: (A) with gastric diseases and periodontal disease; (B) with gastric diseases and no periodontal disease; (C) without gastric diseases and without periodontal disease, (D) without gastric diseases and with periodontal disease. Supra and subgingival plaque samples were collected from posterior teeth of the individuals with sterile paper points, and prepared for Polymerase Chain Reaction analysis. Fisher's exact test was used for detecting statistical differences between groups (p<0.05). RESULTS: H. pylori was detected in supragingival plaque of 9/36 (25%) of group A, 1/31 (0.3%) of group B, 0 (0%) of group C and 3/36 (8.3%) of group D. No subgingival samples were positive for H. pylori. There was a statistically higher prevalence of H. pylori in groups A and D when compared to B and C (p<0.05). CONCLUSION: H. pylori was detected in the supragingival plaque, but not in the subgingival plaque, of individuals with periodontal disease and upper gastric diseases. There was an association between the supragingival colonization of H. pylori and oral hygiene parameters such as the presence of plaque and gingival bleeding.

Detection of cytotoxin genotypes of Helicobacter pylori in stomach, saliva and dental plaque.

BACKGROUND: The aim of this study was to detect the presence of Helicobacter pylori and its virulent cagA genes in the oral cavity of individuals with upper gastric diseases. Sixty-two individuals (42+/-2.3 years) with dispepsy symptoms, referred for gastroscopy and who were H. pylori positive in the gastric biopsy, were recruited and separated in two groups: case group-individuals with gastric disease (n = 30); control group-individuals with no gastric disease (n = 32); saliva, dental plaque and biopsy samples were collected from all individuals. Oral and biopsy samples were analyzed by PCR using specific primers for H. pylori 16S ribosomal and cagA genes. PCR products were sequenced for DNA homology confirmation. H. pylori was detected neither in dental plaque nor in saliva in the control group. In the case group H. pylori DNA was detected in 16/30 (53.3%) saliva samples and in 11/30 (36.6%) dental plaque samples. The cagA gene was detected in 13/30 (43.3%) gastric biopsies, in 7/16 (43.8%) saliva samples, and in 3/11 (27.3%) dental plaque samples. Eighteen (60.0%) individuals in the case group were H. pylori positive both in oral and biopsy samples, and 8 (26.6%) of those were positive for cagA-H. pylori DNA. H. pylori and its virulent clone showed a higher prevalence in the oral cavity of individuals in the case group than in the control group (p < 0.05). Our results suggest that dental plaque and saliva may serve as temporary reservoir for H. pylori and its virulent cagA variant in individuals with gastric disease.

Higher levels of salivary MUC5B and MUC7 in individuals with gastric diseases who harbor Helicobacter pylori.

OBJECTIVE: The aim of the present study was to assess the salivary levels of MUC5B and MUC7 in individuals with dyspeptic disease and Helicobacter pylori (H. pylori) in the stomach, compared to individuals without dyspeptic disease. METHODS: 30 individuals with dyspeptic disease, who underwent endoscopy for upper gastrointestinal complaints at Hospital Pedro Ernesto-RJ, Brasil and tested positive for H. pylori, and 23 controls with no dyspeptic disease, with mean age 53.5+/-4.4 years, were included in the study. Saliva samples and 3 antral biopsy were taken for PCR analysis and histologic examination. In addition, saliva samples were tested by ELISA with F2 monoclonal antibody and EU7A antibody against MUC7, to determine MUC5B and MUC7 levels, prior to endoscopic examination. The expression pattern of the proteins was quantified by comparison to a pooled saliva sample of 19 healthy volunteers. RESULTS: MUC5B and MUC7 salivary levels were higher in the individuals with dyspeptic disease than in controls (p<0.0001). 33.3% (9/30) of the dyspeptic individuals and 0% of the controls had H. pylori in the oral cavity. CONCLUSIONS: Individuals with gastric diseases, with H. pylori in the stomach, showed higher levels of salivary H. pylori receptors-MUC5B and MUC7-than individuals without gastric diseases. These results suggest that higher levels of specific salivary mucins could be useful as risk indicators for infection by H. pylori.

Frequencies of GSTM1, GSTT1, and GSTP1 polymorphisms in a Brazilian population

The glutathione S-transferase (GST) family of enzymes has a vital role in phase II of biotransformation of environmental carcinogens, pollutants, drugs and other xenobiotics. GSTs are polymorphic, with the type and frequency of polymorphism being ethnic dependent. Polymorphisms in GST genes have been shown to be associated with susceptibility to disease and disease outcome. We determined the frequencies of GSTM1, GSTT1 and GSTP1 polymorphisms in 591 volunteers who had been residents of Rio de Janeiro for at least six months. Blood was collected and DNA extracted by proteinase K/SDS digestion. Information about social habits and health problems was also recorded. GSTM1 and GSTT1 polymorphisms were analyzed by a PCR-Multiplex procedure, whereas GSTP1 polymorphism was analyzed by PCR-RFLP. We found that 42.1% (48.9% of whites and 34.2% of non-whites) of the individuals had the GSTM1 null genotype, whereas 25.4% (25.1% of whites and 25.7% of non-whites) had the GSTT1 null genotype. The genotypic distribution of GSTP1 was 49.7% I/I, 38.1% I/V, and 12.2% V/V, whereas the allelic frequencies were 0.69 for the Ile allele, and 0.31 for the Val allele. The frequencies of GST polymorphisms in this Brazilian population were found to be different from those observed in other populations, particularly of other South American countries.