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Human bocavirus (HBoV) is an emerging virus detected around the world that may be associated with cases of acute gastroenteritis (AGE). However, its contribution to AGE has not been elucidated. This study aimed to describe the frequency, clinical features, and HBoV species circulation in children up to 5 years with or without AGE symptoms in Acre, Northern Brazil. A total of 480 stool samples were collected between January and December 2012. Fecal samples were used for extraction, nested PCR amplification, and sequencing for genotyping. Statistical analysis was applied to verify the association between epidemiological and clinical characteristics. Overall, HBoV-positivity was 10% (48/480), with HBoV-positive rates of 8.4% (19/226) and 11.4% (29/254) recorded in diarrheic and non-diarrheic children, respectively. The most affected children were in the age group ranging between 7 and 24 months (50%). HBoV infection was more frequent in children who live in urban areas (85.4%), use water from public networks (56.2%), and live with adequate sewage facilities (50%). Co-detection with other enteric viruses was 16.7% (8/48) and the most prevalent coinfection was RVA+ HBoV (50%, 4/8). HBoV-1 was the most frequent species detected in diarrheic and non-diarrheic children, responsible for 43.8% (21/48) of cases, followed by HBoV-3 (29.2%, 14/48) and HBoV-2 (25%, 12/48). In this study, HBoV infection was not always associated with AGE, as most HBoV cases belonged to the non-diarrheal group. Future studies are warranted in order to determine the role of HBoV in causing acute diarrhea disease.

Dehydroepiandrosterone (DHEA) is a steroid hormone secreted by the adrenal glands, gonads and brain. It is a precursor to sex hormones and also is known to have immune modulatory activity. However, little is known about the relationship between DHEA and neutrophils and thus our study evaluates the influence of DHEA in the effector functions of neutrophils. Human neutrophils were treated in vitro with DHEA and further infected with Salmonella enterica serovar Typhimurium. The treatment of neutrophils with 0.01 μM of DHEA increased the phagocytosis of Salmonella independent of TLR4 as the treatment did not modulate the TLR4 expression. Additionally, DHEA caused a decrease in ROS (reactive oxygen species) production and did not influence the formation of the neutrophil extracellular trap (NET). Steroid treated neutrophils, infected or stimulated with LPS (lipopolysaccharide), showed reduced production of IL-8, compared to untreated cells. Also, the protein levels of p-NFκB were decreased in neutrophils treated with DHEA, and this reduction could explain the reduced levels of IL-8. These results led us to conclude that the steroid hormone DHEA has important modulatory functions in neutrophils.

Serum levels of interleukin 2 (IL-2), interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 10 (IL-10), interleukin 17 (IL-17), interferon gamma (IFN-γ), tumor necrosis factor α (TNF-α), and interleukin 1β (IL-1β), cytokines involved in the immune response, were investigated in 75 Leishmania-positive blood donors living in endemic areas. Based on their status in 2011 and 2015, the subjects were clustered into three groups: positive for at least one diagnostic method in both years, but lacking clinical progression to disease (G1); positive on at least one method in 2011 but negative in 2015 (G2); negative on all methods in both years (G3). Donors were interviewed for sociodemographic data collection and underwent clinical evaluation and laboratory tests. Serum cytokines were quantified using a CBA Flex set (BD Biosciences). Significant differences were found for all the cytokines evaluated, with lower concentrations in consistently Leishmania-negative individuals. The exception was IFN-γ, with similar levels among all donors. No changes consistent with active disease were observed in the laboratory results for Leishmania-positive donors who underwent clinical evaluation, none of whom progressed to disease. This suggests that infection control is associated with serum IL-17 levels. Resolution of Leishmania infection in positive donors may be related to high levels of IL-17 and low levels of IL-10, highlighting the role played by IL-17 in asymptomatic Leishmania-infected individuals.

Viral hepatitis, syphilis, HIV, and tuberculosis infections in prisons have been identified globally as a public health problem. Tuberculosis (TB) and viral hepatitis co-infection may increase the risk of anti-tuberculosis treatment-induced hepatotoxicity, leading to the frequent cause of discontinuation of the first-line anti-tuberculosis drugs. Therefore, the aim of this cross-sectional study was to investigate the epidemiological features of HCV, HBV, syphilis and HIV infections among bacteriologically confirmed tuberculosis prisoners in Campo Grande (MS), Central Brazil. The participants who agreed to participate (n = 279) were interviewed and tested for the presence of active or current HCV, HBV, syphilis and HIV infections. The prevalence of HCV exposure was 4.7% (13/279; 95% CI 2.2-7.1). HCV RNA was detected in 84.6% (11/13) of anti-HCV positive samples. Out of 279 participants, 19 (6.8%; 95% CI 4.4-10.4) were HIV co-infected, 1.4% (4/279, 95% CI 0.5-3.8) had chronic hepatitis B virus (HBsAg positive) and 9.3% (26/279, 95% CI 6.4-13.4) had serological marker of exposure to hepatitis B virus (total anti-HBc positive). The prevalence of lifetime syphilis infection (anti-T. pallidum positive) was 10% (28/279, 95% CI 7.0-14.2) and active syphilis (VDRL ≥ 1/8 titre) was 5% (14/279, 95% CI 2.9-8.3). The prevalence of TB/HCV co-infection among prisoners with HIV (15.8%) was higher than among HIV-non-infected prisoners (3.8%; P

The lifetime risk of HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) development differs among ethnic groups. To better understand these differences, this prospective cohort study was conducted to investigate the cytokine profile and the HTLV-1 proviral load (PVL) in Japanese and non-Japanese populations with HAM/TSP and asymptomatic carriers (ACs). The serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-α, and IFN-γ levels were quantified using the Cytometric Bead Array in 40 HTLV-1-infected patients (11 HAM/TSP and 29 ACs) and 18 healthy controls (HCs) in Brazil. Among ACs, 15 were Japanese descendants and 14 were non-Japanese. Of 11 patients with HAM/TSP, only one was a Japanese descendant. The HTLV-1 PVL was quantified by real-time PCR. The HTLV-1 PVL was 2.7-fold higher in HAM/TSP patients than ACs. Regardless of the clinical outcome, the PVL was significantly higher in patients younger than 60 years than older patients. The HAM/TSP and ACs had higher IL-10 serum concentrations than that of HCs. The ACs also showed higher IL-6 serum levels than those of HCs. According to age, the IL-10 and IL-6 levels were higher in ACs non-Japanese patients older than 60 years. HAM/TSP patients showed a positive correlation between IL-6 and IL-17 and a negative correlation between the PVL and IL-17 and IFN-γ. In the all ACs, a significant positive correlation was observed between IL-2 and IL-17 and a negative correlation was detected between IL-10 and TNF-α. Only 6.25% of the Japanese patients were symptomatic carriers, compared with 41.67% of the non-Japanese patients. In conclusion, this study showed that high levels of HTLV-1 PVL was intrinsicaly associated with the development of HAM/TSP. A higher HTLV-1 PVL and IL10 levels found in non-Japanese ACs over 60 years old, which compared with the Japanese group depicts that the ethnic background may interfere in the host immune status. More researches also need to be undertaken regarding the host genetic background to better understand the low frequency of HAM/TSP in Japanese HTLV-1-infected individuals.

Noroviruses (NoVs) are important cause of gastroenteritis in humans worldwide. Genotype GII.4 is responsible for the majority of outbreaks reported to date. This study describes, for the first time in Brazil, the circulation of NoV GII.4 variant Sydney 2012 in faecal samples collected from children aged less than or equal to eight years in Rio Branco, state of Acre, northern Brazil, during July-September 2012.