Association between the Arg72Pro Genotypes in the TP53 Gene and Ile655Val in the HER2 Gene and the Risk of Developing Breast Cancer in the Population of Amapá, Northern Brazil.

Background: The polymorphisms Arg72Pro in the TP53 gene (rs1042522) and Ile655Val in the HER2 gene (rs1136201) have been related to susceptibility to several types of cancer. Different studies show the association of these polymorphisms with breast cancer, so our aim in this study was to investigate whether the Arg72Pro and Ile655Val polymorphisms have any influence on the risk of developing breast cancer in women from the city of Macapá, Amapá, located in the brazilian amazon region.

Methods And Results: We then analyzed 80 DNA samples from women with breast cancer and 83 DNA samples from women without the disease, by the Restriction Fragment Length Polymorphism - Polymerase Chain Reaction (PCR-RFLP) technique.

Syphilis and Co-Infections with HIV-1, HBV, and HCV among People Who Use Crack-Cocaine in Northern Brazil.

The rates of syphilis and viral co-infections among people who use crack-cocaine (PWUCC) were assessed in this study. This cross-sectional study relied on biological and self-reported socio-behavioral data from a convenience sample of 990 PWUCC from twenty-six municipalities in the states of Amapá and Pará, northern Brazil. Blood samples were collected to assess the presence of using the Rapid Qualitative Test (RQT) and the Venereal Disease Research Laboratory (VDRL).

Detection and Genetic Characterization of Hepatitis B and D Viruses: A Multi-Site Cross-Sectional Study of People Who Use Illicit Drugs in the Amazon Region.

Hepatitis B (HBV) and delta (HDV) viruses are endemic in the Amazon region, but vaccine coverage against HBV is still limited. People who use illicit drugs (PWUDs) represent a high-risk group due to common risk behavior and socioeconomic factors that facilitate the acquisition and transmission of pathogens. The present study assessed the presence of HBV and HBV-HDV co-infection, identified viral sub-genotypes, and verified the occurrence of mutations in coding regions for HBsAg and part of the polymerase in HBV-infected PWUDs in municipalities of the Brazilian states of Amapá and Pará, in the Amazon region.

Hepatitis B Virus Infection among People Who Use Illicit Drugs: Prevalence, Genotypes and Risk Factors in the State of Amapá, Northern Brazil.

Several records of high prevalence of HBV have been made in northern Brazil. Among risk groups for viral infection, people who use illicit drugs (PWUDs) stand out, especially if they inject drugs and engage in risky sexual behavior. In this study, the prevalence, genotype distribution and factors associated with hepatitis B virus (HBV) exposure in PWUDs were estimated.

Prevalence and risk factors for HIV-1 infection in people who use illicit drugs in northern Brazil.

Background: People who use illicit drugs (PWUDs) have a high risk of viral infections. To date, there is a paucity of information on HIV infection among PWUDs in remote Brazilian regions. This study determined the prevalence and factors associated with HIV-1 infection among PWUDs in northern Brazil.

Hepatitis C virus infection status and associated factors among a multi-site sample of people who used illicit drugs in the Amazon region.

Background: Elevated rates of Hepatitis C Virus (HCV) infection have been reported in epidemiological studies with people who used illicit drugs (PWUIDs) in different Brazilian regions. In Brazil's Amazon region, studies have already identified the common use of illicit drugs among adolescents and the high prevalence of HCV infections among PWUIDs. However, all studies done with PWUIDs were conducted with small samples and within limited geographic coverage.

Estimates of interethnic admixture in the Brazilian population using a panel of 24 X-linked insertion/deletion markers.

Objectives: In this study, we aimed to identify ancestry informative haplotypes and make interethnic admixture estimates using X-chromosome markers.

Methods: A significant sample (461 individuals) of European, African, and Native American populations was analyzed, and four linkage groups were identified. The data obtained were used to describe the ancestral contribution of populations from four different geographical regions of Brazil (745 individuals).

X-linked insertion/deletion polymorphisms: forensic applications of a 33-markers panel.

Insertion/deletion (INDEL) polymorphisms are diallelic markers with potential characteristics for use in forensics and biological anthropology, including: the simplicity of laboratory analysis, the possibility of genotyping many markers in a single PCR multiplex reaction, as well as analyzing markers with special inheritance types, such as those linked to the X chromosome (X-INDEL). In this work we developed a laboratory analysis methodology using a 33-INDEL marker panel for the X chromosome in a single PCR multiplex reaction, followed by a capillary electrophoresis run. We employed the panel to genotype a sample of 351 individuals of a mixed population from the Brazilian Amazon.