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Envolvimento de biomarcadores endoteliais na chikungunya crônica

2026-04-22T19:01:15Z

Título: Envolvimento de biomarcadores endoteliais na chikungunya crônica Autor(es): Furtado, Frederico Luis Braz Abstract: Introduction: Chikungunya is an arboviral disease responsible for triggering an intense inflammatory response, associated with long-lasting clinical manifestations in chronic cases. In the last decade, it has affected millions of people in the Americas, Africa, Asia, and Europe, becoming a major public health problem due to its significant impact on quality of life. In this context, the study of endothelial biomarkers can contribute to clarifying the prognosis of the disease and its clinical repercussions. Objective: To investigate biomarkers of endothelial injury in chronic chikungunya. Materials and methods: Cross-sectional study with 34 chronic cases, selected from the cohort of the Oliveira Pombo Basic Health Unit, linked to the “Study of the natural history and therapeutic response of Chikungunya focusing on acute and chronic musculoskeletal manifestations in Fortaleza-CE”. Venous blood samples were collected for the measurement of endothelial biomarkers (ANG-2, VCAM-1, and SYN- 1), in addition to clinical data, such as comorbidities and symptoms, extracted from the cohort questionnaires. Results: The mean age of chronic cases was 45.11 ± 15.86 years, with 28 (76.47%) being female. Twenty (58.82%) participants belonged to the group with 360 days of disease duration. The most prevalent symptoms were morning stiffness (28; 82.35%), arthralgia (22; 64.71%), and edema (16; 47.06%). In the comparison between the three groups of chronic patients with different disease durations (180, 360, and 720 days) and the control group, the biomarkers ANG-2, VCAM-1, and SYN-1 showed statistically significant differences (p = 0.007; p = 0.004; p < 0.001, respectively). Increased levels of ANG-2 (p = 0.037) were observed in patients with and without depression, as well as reductions in VCAM-1 (p = 0.047) and SYN-1 (p = 0.036) in cases with and without memory impairment. SYN-1 levels were increased in patients with fever (p = 0.041) and reduced in those with blurred vision (p = 0.019) and alopecia (p = 0.009), compared to those without these symptoms. Only the biomarkers ANG-2 and VCAM-1 showed a correlation with disease duration, with a moderate and positive correlation for ANG-2 (Rho = 0.456; p = 0.006) and a weak and negative correlation for VCAM-1 (Rho = -0.369; p = 0.034). ANG-2 was the only biomarker with good predictive performance in the AUC-ROC curve = 0.864 and 95% CI (0.725 - 1000), while VCAM-1 and SYN-1 presented, respectively, AUC-ROC = 0.605 and 95% CI (0.338 – 0.872); AUC-ROC = 0.519 and 95% CI (0.148 – 0.890). Conclusion: Increased levels of ANG-2 and reduced levels of VCAM-1 were associated with disease duration in the evaluated cases. SYN-1 may be related to the presence of symptoms such as fever, memory impairment, blurred vision, and alopecia in patients with chronic chikungunya. Tipo: Tese

Modelagem integrada de redes Multilayer, Análises Espaciais e Aprendizado de Máquina na investigação da disseminação de COVID-19 e de arboviroses (Dengue, Zika e Chikungunya) em Fortaleza

2026-02-18T11:59:15Z

Título: Modelagem integrada de redes Multilayer, Análises Espaciais e Aprendizado de Máquina na investigação da disseminação de COVID-19 e de arboviroses (Dengue, Zika e Chikungunya) em Fortaleza Autor(es): Silva, Rôney Reis de Castro e Abstract: The rise of arboviral diseases—and, in particular, COVID-19—calls for approaches that integrate multiple territorial dimensions. This thesis adopts an integrated approach combining multilayer networks, statistical and spatial analyses, and interpretable machine learning to understand diffusion patterns of COVID-19, dengue, zika, and chikungunya in Fortaleza (CE), 2020–2024. Layers comprise epidemiological, socioeconomic/demographic, infrastructure, and political/HDI variables; intralayer relations are defined by neighborhood similarity, and interlayer relations by associations between variables. The COVID-19 dataset was built from weekly epidemiological bulletins, aggregated by month and neighborhood, prioritizing territorial patterns comparable across diseases. Spatially, we use global and local autocorrelation (Moran’s I, LISA) to identify clusters and local patterns; in the network domain, we compute centralities and apply community detection. Predictive models (Random Forest, XGBoost) and SHAP-based explanations assess the variables’ predictive power and contributions. K-means clustering synthesizes territorial profiles by combining structural and epidemiological characteristics. Findings reveal spatial heterogeneity and cross-layer differences, with territorial convergences and divergences that inform vulnerability assessment and prioritization. As a practical contribution, the thesis includes an Appendix: Methodological Enhancement Proposal (“Integrated Framework”) to guide future standardization and support municipal decision-making. Tipo: Tese

Impacto da volemia sobre a barreira funcional do epitélio intestinal em pacientes críticos com insuficiência cardíaca aguda

2026-01-13T15:14:55Z

Título: Impacto da volemia sobre a barreira funcional do epitélio intestinal em pacientes críticos com insuficiência cardíaca aguda Autor(es): Monte Neto, Vicente Lopes Abstract: The regulation of blood volume (volemic homeostasis) depends on the interaction between the cardiovascular, renal, and intestinal systems, whose dynamics are not yet fully understood. In cases of Acute Heart Failure (AHF), these systems may be affected, particularly the intestinal barrier, which undergoes increased permeability. This phenomenon, poorly studied and with limited diagnostic tools, may compromise intestinal epithelial cells. The objective of this study was to investigate how acute changes in blood volume influence the integrity and function of the intestinal barrier in patients with AHF. This was a cross-sectional study, approved by the Research Ethics Committee of the Vale do Acaraú State University (CEP/CONEP), which evaluated intestinal barrier integrity in 80 individuals between March 2022 and January 2024. The sample consisted of 40 patients with AHF (clinical and echocardiographic diagnosis), 14 controls with Coronary Artery Disease (CAD), and 26 healthy controls. Intestinal permeability was measured using the lactulose/mannitol (L:M) urinary excretion ratio by HPLC-PAD. Patients with AHF presented a median L:M ratio of 0.1094 (IQR 25–75%: 0.0411–0.2732), representing an increase of 277.2% compared to healthy volunteers and 466.8% compared to the CAD group, with a statistically significant difference according to the Kruskal-Wallis test (P = 0.001). Kendall’s correlation was used to assess the association between the L:M ratio and Pro-BNP levels, as well as hemodynamic parameters obtained by echocardiography. Multiple regression was performed considering the L:M ratio as the dependent variable and clinical, therapeutic, and in-hospital prognostic characteristics as independent variables. Kendall’s correlation indicated a negative association between the Left Ventricular Outflow Tract (LVOT) Velocity-Time Integral (VTI) and L:M ratio, without statistical significance. Multiple regression did not show significant associations between L:M ratio and clinical, therapeutic, or prognostic variables. Conclusion: Patients with AHF presented increased intestinal permeability, reflected by elevated L:M ratio, suggesting epithelial barrier dysfunction and reduced effective absorptive area. These findings indicate a relevant interaction between cardiovascular dysfunction and intestinal integrity. Tipo: Tese

Síndrome Respiratória Aguda Grave por COVID-19 em crianças e adolescentes no Brasil (2020 a 2024) : análise das características clínicas, epidemiológicas e vacinais

2026-01-05T14:32:36Z

Título: Síndrome Respiratória Aguda Grave por COVID-19 em crianças e adolescentes no Brasil (2020 a 2024) : análise das características clínicas, epidemiológicas e vacinais Autor(es): Viana, Vânia Angélica Feitosa Abstract: The COVID-19 pandemic underscored the critical importance of epidemiological surveillance of Severe Acute Respiratory Syndrome (SARS) in children and adolescents. Although this demographic is less susceptible to severe forms of the disease, it was not exempt from complications, hospitalizations, and fatalities. Brazil recorded one of the highest rates of pediatric mortality from COVID-19 globally. Within this context, this study aims to elucidate the determinants of morbidity and mortality in children and adolescents (0-19 years) between 2020 and 2024 through a comprehensive and detailed analysis of SARS cases due to COVID- 19. This is a retrospective cohort study conducted using publicly available secondary data. Among the 34,369 cases analyzed, disparities in case fatality rates (CFR) were observed. Higher CFRs were identified in the North (13.02%) and Northeast (11.6%) regions, among Indigenous populations (22.54%), rural residents (14.34%), municipalities with a low Human Development Index (HDI) (9.41%), and the 15-19 age group. The circulation of the Gamma and Delta variants (2021) was associated with peaks in incidence and mortality, whereas during the Omicron variant period (2022–2024), mortality decreased despite periods of high incidence. Nosocomial cases had a significantly higher CFR (14.6%) than community- acquired cases (5.3%), particularly among adolescents (15-19 years) and in the North and Northeast regions. Sustained pediatric intensive care unit (ICU) occupancy rates (25–32%) after 2022, coupled with a sharp increase in ICU admissions among children aged 0-4 years (from approximately 52% in 2020–2021 to over 78% in 2024), highlight the critical demand for targeted strategies focused on the pediatric population. Comorbidities such as immunosuppression (OR: 4.44) and Down syndrome (OR: 3.13) were critical predictors of severe outcomes. Vaccination demonstrated a significant protective effect; however, a marked disparity in vaccination coverage was observed, with children under 5 years (95.9% unvaccinated) and the North/Northeast regions showing the lowest rates. This study demonstrated that SARS due to COVID-19 in children and adolescents in Brazil was characterized by significant sociodemographic, regional, clinical, and vaccination disparities. Consequently, the findings emphasize the necessity for integrated public health policies to reduce pediatric morbidity and mortality in future health emergencies. These should include regionalized strategies for vulnerable populations, the strengthening of pediatric ICU capacity, enhanced hospital infection control, and the equitable expansion of vaccination programs. Tipo: Tese