The association of HPV genotype with the regression, persistence or progression of low-grade squamous intraepithelial lesions.

BACKGROUND: Human papillomavirus (HPV) is a highly prevalent sexually transmitted virus causing cytological alterations that precede cervical cancer. Approximately 130 genotypes have been sequenced. Low-grade squamous intraepithelial lesions (LSIL) are the most frequent cytological alteration and have an uncertain behavior. OBJECTIVES: To analyze the frequency of HPV types in LSIL and their association with the regression, persistence or progression of these lesions. METHODS: A cohort study of forty patients with LSIL cytology was conducted from December 2007 to March 2011. The follow-up lasted two years and included cytology and colposcopy. HPV detection was performed using PCR, and genotyping was performed using PCR-specific and RFLP techniques. RESULTS: DNA-HPV was detected in 87% (35/40) of the cases, with oncogenic HPV accounting for 76%; type 16 in 32% (11/35) and type 18 in 20%. LSIL regression, persistence and progression rates at the end of the study were 60%, 23% and 17%, respectively. There was 50% regression in lesions in the high oncogenic risk group (types 16 and 18). CONCLUSION: HPV 16 was the most frequent genotype found in LSIL. The persistence and progression of the LSIL were related to the persistence of oncogenic HPV. The longer the follow-up time, the lower the LSIL persistence rate and the higher its regression rate; the progression rate remained stable. In addition to the presence of oncogenic HPV, other factors are necessary for the progression of LSIL.

Epstein-Barr virus DNA associated with gastric adenocarcinoma and adjacent non-cancerous mucosa in patients from Manaus, Brazil.

Gastric cancer is one of most frequent causes of death in Brazil. The city of Manaus has one of the highest incidences of this disease in Brazil. The Epstein-Barr virus (EBV) is a ubiquitous herpesvirus that is classified as a group 1 carcinogen by the International Agency for Research on Cancer. We obtained biopsies from 6 control subjects and 10 patients with gastric carcinomas living in Manaus. In the patients, the samples were taken from tumors and from adjacent non-cancerous mucosa. These samples were screened for EBV DNA by PCR to amplify the 288-bp fragments from the Bam M region. The EBV DNA was detected in 8 of the 10 tumor cases and in none of the 6 control subjects. In the positively identified samples, EBV DNA was detected in five corresponding resection margins. Previous research indicated only a weak association between EBV and gastric cancer. We suggest that EBV should be considered as a risk factor for gastric adenocarcinomas in Manaus.

Analysis of human papillomavirus and Epstein-Barr virus infection and aberrant death-associated protein kinase methylation in high-grade squamous intraepithelial lesions.

This study was conducted to investigate the presence of Epstein-Barr virus (EBV) and human papillomavirus (HPV) and the promoter methylation status of the death-associated protein kinase (DAPK) gene in high-grade intraepithelial lesions. Viral infection was analyzed using polymerase chain reaction (PCR), and promoter methylation status was evaluated using chemical modification by sodium bisulfite followed by PCR. A total of 24 samples were studied. HPV was detected in 16.6%, EBV in 16.6%, and HPV/EBV coinfection in 16.6%. No virus infection was detected in 50% of the samples studied. DAPK promoter methylation was observed in 29.2% of the analyzed samples. There was no significant correlation between DAPK methylation and viral infection. DAPK methylation was detected in 28% of HPV-positive lesions, in 28% of HPV- and EBV-positive lesions, and in 44% (3/7) of the samples without viral infection. There was no observed methylation in samples with isolated EBV infection. In DAPK unmethylated samples, HPV infection was found in 12%, EBV infection in 23%, HPV/EBV coinfection in 12%, and an absence of HPV and EBV infection in 53%. The promoter methylation of the DAPK gene is an important event during carcinogenesis and may have potential clinical application as a marker for the progression and prognosis of cancer.

Personalized diagnosis by cached solutions with hypertension as a study model.

Statistical modeling of links between genetic profiles with environmental and clinical data to aid in medical diagnosis is a challenge. Here, we present a computational approach for rapidly selecting important clinical data to assist in medical decisions based on personalized genetic profiles. What could take hours or days of computing is available on-the-fly, making this strategy feasible to implement as a routine without demanding great computing power. The key to rapidly obtaining an optimal/nearly optimal mathematical function that can evaluate the "disease stage" by combining information of genetic profiles with personal clinical data is done by querying a precomputed solution database. The database is previously generated by a new hybrid feature selection method that makes use of support vector machines, recursive feature elimination and random sub-space search. Here, to evaluate the method, data from polymorphisms in the renin-angiotensin-aldosterone system genes together with clinical data were obtained from patients with hypertension and control subjects. The disease "risk" was determined by classifying the patients' data with a support vector machine model based on the optimized feature; then measuring the Euclidean distance to the hyperplane decision function. Our results showed the association of renin-angiotensin-aldosterone system gene haplotypes with hypertension. The association of polymorphism patterns with different ethnic groups was also tracked by the feature selection process. A demonstration of this method is also available online on the project's web site.

Serum concentration and increased temperature alter Mayaro virus RNA and protein synthesis in Aedes albopictus (mosquito)-infected cells

We have previously shown the inhibition of Mayaro virus multiplication in Aedes albopictus-infected cells maintained at a supraoptimal temperature for growth (37§C) and a stimulation of virus production in response to high serum concentrations in the incubation medium. In the present study, we addressed the question of how the effect of continuous heat stress and high serum concentration soon after infection interfere with virus macromolecule synthesis. Cells maintained at 28§C in the presence of 2 percent serum synthesized a viral genomic RNA of 12 kb and a subgenomic RNA of 5.2 kb 6 h post-infection. Analysis of the protein profile showed the presence of the viral nucleocapsid protein of 34 kDa (P34). However, if infected cells were maintained at 37§C, a smear starting immediately below the 5.2-kb RNA was noticed and the viral P34 was not detected by SDS-PAGE. Addition of 10 percent serum to the growth medium of infected cells maintained at 37§C results in a viral RNA profile and proteins synthesis similar to those observed in cultures kept at 28§C, i.e., the smear was not observed and the P34 protein was detected. The results suggest that the inhibition of virus multiplication by temperature may be related to the inhibition of viral nonstructural protein synthesis early during infection. The presence of high serum levels in the incubation medium protects macromolecule synthesis against heat stress

Translocation of heat shock proteins into isolated nuclei of Aedes albopictus cells

Labelled heat shock proteins of 82 kDa,70 and a group of low molecular weight are present in the post-mitochondrial supernatant obtained from Aedes albopictus cells.These proteins in the post-mitochondrial extract are transported specifically to the nuclear compartment when incubated with isolated unlabelled nuclei.The relative amounts of each protein transported were 4.7,24.1 and 3,1% for the 82-k-Daand 70-kDa and for the low molecular weght proteins, respectively.Incubation of radiolabelled post-mitochondrial extract with unlabelled nuclei at 30 C or 37 C did not modify the perecentage of proteins translocated

Effect of high temperature on Aedes albopictus cells infected with Mayaro virus

the multiplication of Mayaro virus in Aedes albopictus cells was drastically inhibited after incubation at 37-C. The effect of short-term exposure of infected cells to high temperatures (heat shock) produced a preferential translation of the heat shock messengers when compared to the viral mRNAs. When cells were shifted back to 28-C (the optimum growth temperature for Aedes albopictus cells), preferential translation of viral mRNA occurred. Although the infected cells were programmed for preferential translation of viral messengers, the therminal treatment was able to shif the translational machinery towards synthesis of heat shock proteins