Assessment of Cross-Reactivity of Chimeric Trypanosoma cruzi Antigens with Crithidia sp. LVH-60A: Implications for Accurate Diagnostics.

This study focuses on developing accurate immunoassays for diagnosing Chagas disease (CD), a challenging task due to antigenic similarities between Trypanosoma cruzi and other parasites, leading to cross-reactivity. To address this challenge, chimeric recombinant T. cruzi antigens (IBMP-8.1, IBMP-8.2, IBMP-8.3, and IBMP-8.4) were synthesized to enhance specificity and reduce cross-reactivity in tests. While these antigens showed minimal cross-reactivity with leishmaniasis, their performance with other trypanosomatid infections was unclear. This study aimed to assess the diagnostic potential of these IBMP antigens for detecting CD in patients with Crithidia sp. LVH-60A, a parasite linked to visceral leishmaniasis-like symptoms in Brazil. This study involved seven Crithidia sp. LVH-60A patients and three Leishmania infantum patients. The results indicated that these IBMP antigens displayed 100% sensitivity, with specificity ranging from 87.5% to 100%, and accuracy values between 90% and 100%. No cross-reactivity was observed with Crithidia sp. LVH-60A, and only one L. infantum-positive sample showed limited cross-reactivity with IBMP-8.1. This study suggests that IBMP antigens offer promising diagnostic performance, with minimal cross-reactivity in regions where T. cruzi and other trypanosomatids are prevalent. However, further research with a larger number of Crithidia sp. LVH-60A-positive samples is needed to comprehensively evaluate antigen cross-reactivity.

Time trends and social security burden of temporary work disability due to chronic venous disease in Brazil.

BACKGROUND: Chronic venous disease (CVD) and disability are worldwide problems and have significant socioeconomic implications. This study aims to analyze the time trends and social security burden of temporary work disability due to CVD in Brazil. METHODS: An ecological time series study using the Brazilian Social Security System database was performed from 2005 to 2014. Data from all benefits granted to workers with temporary disability due to CVD were analyzed. The cases were identified using diagnosis codes I83-I83.9 of the International Classification of Diseases 10th Revision (ICD-10). The time trend analyses were performed by the Joinpoint Regression Model, with sex, age, regions, income, and category of affiliation as variables. Crude and age-standardized rates were calculated. RESULTS: A total of 429,438 benefits were granted for temporary work disability due to CVD from 2005 to 2014, with a growing trend and an age-standardized annual percent change (APC) of 3.4 (95% CI: 2.6-4.2) (p < 0.05). Social security expense increased 3.5-fold, and the number of days in benefit doubled from 2005 to 2014. In total, 27,017,818 working days were lost. The average duration of benefits was 55.3 days. The majority of workers were women (68.2%) (p < 0.001), between 30 and 59 years old, employed, had a monthly income ≤2 minimum wages (MW) (83.2%), and lived in the regions southeast (53.6%) and south (29.3%). Significantly higher APCs were observed for women than for men (APC: 4.9, 95% CI: 4.0-5.7 versus APC: 1.2, 95% CI: 0.1-2.4). All regions in Brazil had a significant growing trend, except in the north. No significant growth was observed in the age group of 60-69 years. A decreasing trend was observed in workers with monthly incomes above 2 MW (p < 0.05). CONCLUSIONS: Temporary work disability due to CVD and social security burden showed increasing trends with millions of working days lost, particularly among women and low-income workers. Preventing disability is challenging, and public policies are needed to reduce the social and economic impact of disability. Therefore, measures for promoting health at the workplace should be encouraged.

Non-Leishmania Parasite in Fatal Visceral Leishmaniasis-Like Disease, Brazil.

Through whole-genome sequencing analysis, we identified non-Leishmania parasites isolated from a man with a fatal visceral leishmaniasis-like illness in Brazil. The parasites infected mice and reproduced the patient's clinical manifestations. Molecular epidemiologic studies are needed to ascertain whether a new infectious disease is emerging that can be confused with leishmaniasis.

Association Between Zika Virus Microcephaly in Newborns With the rs3775291 Variant in Toll-Like Receptor 3 and rs1799964 Variant at Tumor Necrosis Factor-α Gene.

Congenital Zika syndrome (CZS) is a cluster of malformation, and the mechanisms that lead it are still unclear. Using hypothesis-driven candidate genes and their function in viral infections, single-nucleotide polymorphisms (SNPs) were genotyped by quantitative polymerase chain reaction in a sample population from Sergipe State, Brazil. This study shows that rs3775291 SNP at Toll-like receptor 3, which triggers type I interferon antiviral responses in mothers infected by Zika virus during pregnancy, is associated with CZS occurrence (odds ratio [OR], 2.19; 95% confidence interval [CI], 1.158-4.148). Moreover, rs1799964 SNP at tumor necrosis factor-α gene in CZS babies is associated with severe microcephaly (OR, 2.63; 95% CI, 1.13-6.21).

The Influence of Stress and Anxiety on the Expectation, Perception and Memory of Dental Pain in Schoolchildren.

The aim of this study was to investigate the association of stress and anxiety with the expectation, perception and memory of dental pain among schoolchildren. A follow-up study involving 46 children aged 9 to 12 years was conducted in a public school in the city of Petropolis (RJ), Brazil. Demographic characteristics, stress (children's stress scale), and state and trait anxiety (state⁻trait anxiety inventory) were recorded before a dental procedure to restore the occlusal surface of a permanent first molar under local anaesthetic. Dental pain was assessed using the faces pain scale before (dental pain expectation), immediately after (dental pain perception) and six weeks after (memory of dental pain) the dental procedure. Dental pain expectation scores were significantly higher than dental pain perception, independent of the levels of stress, state anxiety and trait anxiety. Children with high scores of stress (OR 1.05 95%CI 1.02⁻1.09), state anxiety (OR 1.15 95%CI 1.05⁻1.27) and trait anxiety (OR 1.18 95%CI 1.07⁻1.30) were more likely to report greater scores of dental pain expectation. Children anticipated more dental pain than what was actually perceived after the dental restoration. Children with greater levels of stress and anxiety have a distorted evaluation of expected dental pain before the dental procedure.

Leishmania infantum Induces the Release of sTREM-1 in Visceral Leishmaniasis.

Visceral leishmaniasis (VL) is a systemic transmissible disease that remains to be a major global health problem. The inflammatory response during VL is characterized by the release of several cytokines and other pro-inflammatory mediators. Triggering Receptor Expressed on Myeloid Cells (TREM) are a group of evolutionarily conserved membrane-bound surface receptors expressed on neutrophils and monocytes. Engagement of TREM-1 directs intracellular signaling events that drive cytokine production, degranulation, and phagocytosis. In certain inflammatory-associated diseases, TREM-1 can also be found as a soluble form (sTREM-1), which can negatively regulate TREM-1 receptor signaling. In these studies, we now find that high levels of circulating sTREM-1 correlate directly with VL disease severity. In particular, high levels of sTREM-1 were observed in non-survivor VL patients. Furthermore, these levels of sTREM-1 positively correlated with liver size and negatively correlated with leukocyte counts and hemoglobin concentration. Moreover, we found that neutrophils exposure in vitro to Leishmania infantum modulates TREM-1, DAP12, and IL-8 gene expression, while also increasing release of sTREM-1. Finally, results revealed that higher sTREM-1 levels are associated with increasing parasite ratio. Taken together, these studies suggest that L. infantum may modulate TREM-1 in neutrophils and high levels of this molecule is associated with severe VL.

Predicting frequency distribution and influence of sociodemographic and behavioral risk factors of Schistosoma mansoni infection and analysis of co-infection with intestinal parasites.

Geospatial analysis was used to study the epidemiology of Schistosoma mansoni, intestinal parasites and co-infections in an area (Ilha das Flores) in Sergipe, Brazil. We collected individually georeferenced sociodemographic, behavioral and parasitological data from 500 subjects, analyzed them by conventional statistics, and produced risk maps by Kernel estimation. The prevalence rates found were: S. mansoni (24.0%), Trichuris trichiura (54.8%), Ascaris lumbricoides (49.2%), Hookworm (17.6%) and Entamoeba histolytica (7.0%). Only 59/500 (11.8%) individuals did not present any of these infections, whereas 279/500 (55.8%) were simultaneously infected by three or more parasites. We observed associations between S. mansoni infection and various variables such as male gender, being rice farmer or fisherman, low educational level, low income, water contact and drinking untreated water. The Kernel estimator indicated that high-risk areas coincide with the poorest regions of the villages as well as with the part of the villages without an adequate sewage system. We also noted associations between both A. lumbricoides and hookworm infections with low education and low income. A. lumbricoides infection and T. trichiura infection were both associated with drinking untreated water and residential open-air sewage. These findings call for an integrated approach to effectively control multiple parasitic infections.

Impact of visceral leishmaniasis and curative chemotherapy on cytochrome P450 activity in Brazilian patients.

AIMS: The aim of the present study was to investigate the impact of human visceral leishmaniasis (VL) and curative chemotherapy on the activity of cytochrome P450 (CYP) 3A, CYP2C9 and CYP2C19 in patients from an endemic region in Brazil. METHODS: Adult patients with parasitologically confirmed VL were given a CYP phenotyping cocktail, comprising midazolam, omeprazole and losartan, immediately before (Study phase 1), 2-3 days (phase 2) and 3-6 months (phase 3) after curative VL chemotherapy. CYP activity was assessed by the apparent clearance of midazolam (CYP3A), omeprazole/5-hydroxyomeprazol ratio in plasma (CYP2C19) and losartan/E3174 ratio in urine (CYP2C9). RESULTS: Mean values (95% confidence interval) in phases 1, 2 and 3 were, respectively: log apparent midazolam clearance, 1.21 (1.10-1.31), 1.45 (1.32-1.57) and 1.35 (1.26-1.44) ml min(-1) kg(-1) ; omeprazole/5-hydroxyomeprazole ratio, 0.78 (0.61-0.94), 0.45 (0.27-0.63) and 0.37 (0.20-0.55); losartan/E3174 ratio, 0.66 (0.39-0.92), 0.35 (0.20-0.50) and 0.35 (0.16-0.53). Analysis of variance revealed significant differences in CYP3A (P = 0.018) and CYP2C19 (P = 0.008), but not CYP2C9 (P = 0.11) phenotypic activity, across the three study phases. CONCLUSION: The phenotypic activities of CYP3A4 and CYP2C19 were significantly reduced during acute VL compared with post-chemotherapy. We propose that increased plasma concentrations of proinflammatory cytokines during active disease account for the suppression of CYP activity. The failure to detect significant changes in CYP2C9 activity in the overall cohort may reflect differential effects of the inflammatory process on the expression of CYP isoforms, although the possibility of insufficient statistical power cannot be dismissed.

Psychosocial factors and T lymphocyte counts in Brazilian peacekeepers.

OBJECTIVE: To investigate the associations between psychosocial factors and peripheral blood CD4 and CD8 T lymphocyte numbers in Brazilian peacekeepers. METHODS: Venous blood was collected from 759 peacekeepers who had just returned from a peace mission in Haiti. Among the 759 soldiers, 642 individuals completed the psychosocial measures. CD4 and CD8 T lymphocyte counts were measured by flow cytometry using a commercially available kit. Psychosocial factors, including military peace force stressors, clinical stress, anxiety and depression, were recorded. As a reference for T lymphocyte numbers, we measured T lymphocyte counts in 75 blood donors from the Instituto de Biologia do Exército, Rio de Janeiro. RESULTS: The median numbers of CD4 and CD8 T lymphocytes in the blood donors were 819 cells/µl and 496 cells/µl, respectively, with a CD4:CD8 ratio of 1.6. Significantly (p<0.05) lower CD4 T cell counts (759 cells/µl) were recorded for peacekeepers, with similar CD8 levels (548 cells/µl) and smaller CD4:CD8 ratios (1.3, p<0.001) compared to blood donors. These differences were due to a group of 14 military personnel with CD4 and CD8 medians of 308 and 266 cells/µl, respectively. Only one (7.1%) of these 14 individuals was diagnosed with clinical stress compared with 13.5% of the individuals with normal levels of CD4 T lymphocytes. One individual out of 628 (0.16%) had a Lipp's Stress Symptom Inventory score of 3, indicating near exhaustion. CONCLUSION: The prevalence of psychological disorders was low and there were no associations with CD4 or CD8 T cell numbers.

Heme oxygenase-1 promotes the persistence of Leishmania chagasi infection.

Visceral leishmaniasis (VL) remains a major public health problem worldwide. This disease is highly associated with chronic inflammation and a lack of the cellular immune responses against Leishmania. It is important to identify major factors driving the successful establishment of the Leishmania infection to develop better tools for the disease control. Heme oxygenase-1 (HO-1) is a key enzyme triggered by cellular stress, and its role in VL has not been investigated. In this study, we evaluated the role of HO-1 in the infection by Leishmania infantum chagasi, the causative agent of VL cases in Brazil. We found that L. chagasi infection or lipophosphoglycan isolated from promastigotes triggered HO-1 production by murine macrophages. Interestingly, cobalt protoporphyrin IX, an HO-1 inductor, increased the parasite burden in both mouse and human-derived macrophages. Upon L. chagasi infection, macrophages from Hmox1 knockout mice presented significantly lower parasite loads when compared with those from wild-type mice. Furthermore, upregulation of HO-1 by cobalt protoporphyrin IX diminished the production of TNF-α and reactive oxygen species by infected murine macrophages and increased Cu/Zn superoxide dismutase expression in human monocytes. Finally, patients with VL presented higher systemic concentrations of HO-1 than healthy individuals, and this increase of HO-1 was reduced after antileishmanial treatment, suggesting that HO-1 is associated with disease susceptibility. Our data argue that HO-1 has a critical role in the L. chagasi infection and is strongly associated with the inflammatory imbalance during VL. Manipulation of HO-1 pathways during VL could serve as an adjunctive therapeutic approach.

Negative affect predicts posttraumatic stress symptoms in Brazilian volunteer United Nations peacekeepers in Haiti.

Our study evaluated the relationship between positive affect (PA) and negative affect (NA) traits on the development of posttraumatic stress symptoms (PTSS) among peacekeepers. A longitudinal study with 138 army personnel deployed to a peacekeeping mission in Haiti was conducted. An instrument for measuring PA and NA traits was used before deployment. PTSS, indexed by posttraumatic stress disorder Checklist--Military Version (PCL-M) and frequency of stressful situations were measured after return. Regression analysis showed that both NA and number of stressful situations contributed toward increasing PCL-M scores (Adjusted R = 0.25; p < 0.001). We also found that NA traits interact with intensively stressful situations enhancing the occurrence of PTSS (Adjusted R = 0.32; p < 0.001). These findings suggest that NA traits are an important predictor for PTSS among peacekeepers and also worsen the consequences of being exposed to stressful situations.

Estudo do perfil clínico-epidemiológico dos pacientes atendidos pelo Programa de Assistência Domiciliar Terapêutica em AIDS: Vitória, ES - Brasil / Clinical and epidemiological profile of patients attended at home care assistance in AIDS - Vitória, ES - Brazil

Estudo do perfil da clientela exposta à infecção pelo HIV para detectar possíveis falhas e traçar estratégias preventivas e terapêuticas