Half dose ChAdOx1 nCoV-19 vaccine was equivalent to full doses to reduce moderate and severe COVID-19 cases.

Objectives: Previously, we presented the effectiveness of ChAdOx1 nCoV-19 half-dose (HD) immunization for preventing new COVID-19 cases. Here, we evaluated the administration of an HD of ChAdOx1 nCoV-19 in the primary immunization protocol (up to two doses) in reducing moderate and severe cases, hospitalizations, and deaths when compared to the administration of full doses (FD) after a long-term follow-up. Methods: We evaluated data from 29,469 participants between January 2021 and November 2022 who received an HD or FD vaccine and crossed this information with their medical records to identify those who developed moderate or severe cases. All participants were classified into four groups according to their immunization status and followed 500 days after the last vaccine administration. Results: The propensity-score matching analysis indicates that the administration of the two HDs of ChAdOx1 nCoV-19 was equivalent to the use of two FDs to reduce moderate and severe COVID-19 cases. The relative risk of being infected and developing moderate or severe conditions after the administration of at least one HD or FD was similar 150 or 500 days after the administration of the immunizers. Conclusion: Administering two HDs can be used safely as a cost-effective alternative to the primary immunization protocol.

Computational methods applied to syphilis: where are we, and where are we going?

Syphilis is an infectious disease that can be diagnosed and treated cheaply. Despite being a curable condition, the syphilis rate is increasing worldwide. In this sense, computational methods can analyze data and assist managers in formulating new public policies for preventing and controlling sexually transmitted infections (STIs). Computational techniques can integrate knowledge from experiences and, through an inference mechanism, apply conditions to a database that seeks to explain data behavior. This systematic review analyzed studies that use computational methods to establish or improve syphilis-related aspects. Our review shows the usefulness of computational tools to promote the overall understanding of syphilis, a global problem, to guide public policy and practice, to target better public health interventions such as surveillance and prevention, health service delivery, and the optimal use of diagnostic tools. The review was conducted according to PRISMA 2020 Statement and used several quality criteria to include studies. The publications chosen to compose this review were gathered from Science Direct, Web of Science, Springer, Scopus, ACM Digital Library, and PubMed databases. Then, studies published between 2015 and 2022 were selected. The review identified 1,991 studies. After applying inclusion, exclusion, and study quality assessment criteria, 26 primary studies were included in the final analysis. The results show different computational approaches, including countless Machine Learning algorithmic models, and three sub-areas of application in the context of syphilis: surveillance (61.54%), diagnosis (34.62%), and health policy evaluation (3.85%). These computational approaches are promising and capable of being tools to support syphilis control and surveillance actions.

Development of a Cyclic Voltammetry-Based Method for the Detection of Antigens and Antibodies as a Novel Strategy for Syphilis Diagnosis.

The improvement of laboratory diagnosis is a critical step for the reduction of syphilis cases around the world. In this paper, we present the development of an impedance-based method for detecting T. pallidum antigens and antibodies as an auxiliary tool for syphilis laboratory diagnosis. We evaluate the voltammetric signal obtained after incubation in carbon or gold nanoparticle-modified carbon electrodes in the presence or absence of Poly-L-Lysine. Our results indicate that the signal obtained from the electrodes was sufficient to distinguish between infected and non-infected samples immediately (T0') or 15 min (T15') after incubation, indicating its potential use as a point-of-care method as a screening strategy.

Effectiveness of COVID-19 Vaccination on Reduction of Hospitalizations and Deaths in Elderly Patients in Rio Grande do Norte, Brazil.

Since the COVID-19 pandemic emerged, vaccination has been the core strategy to mitigate the spread of SARS-CoV-2 in humans. This paper analyzes the impact of COVID-19 vaccination on hospitalizations and deaths in the state of Rio Grande do Norte, Brazil. We analyzed data from 23,516 hospitalized COVID-19 patients diagnosed between April 2020 and August 2021. We excluded the data from patients hospitalized through direct occupancy, unknown outcomes, and unconfirmed COVID-19 cases, resulting in data from 12,635 patients cross-referenced with the immunization status during hospitalization. Our results indicated that administering at least one dose of the immunizers was sufficient to significantly reduce the occurrence of moderate and severe COVID-19 cases among patients under 59 years. Considering the partially or fully immunized patients, the mean age is similar between the analyzed groups, despite the occurrence of comorbidities and higher than that observed among not immunized patients. Thus, immunized patients present lower Unified Score for Prioritization (USP) levels when diagnosed with COVID-19. Our data suggest that COVID-19 vaccination significantly reduced the hospitalization and death of elderly patients (60+ years) after administration of at least one dose. Comorbidities do not change the mean age of moderate/severe COVID-19 cases and the days required for the hospitalization of these patients.

HIV-1 Gag and Vpr impair the inflammasome activation and contribute to the establishment of chronic infection in human primary macrophages.

The successful establishment of HIV-1 infection is related to inflammasome blocking or inactivation, which can result in the viral evasion of the immune responses and formation of reservoirs in several tissues. In this sense, we aimed to evaluate the viral and cellular mechanisms activated during HIV-1 infection in human primary macrophages that allow an effective viral replication in these cells. We found that resting HIV-1-infected macrophages, but not those activated in classical or alternative patterns, released IL-1ß and other pro-inflammatory cytokines, and showed increased CXCL10 expression, without changes in the NLRP3, AIM2 or RIG-I inflammasome pathways. Also, similar levels of Casp-1, phosphorylated NF-κB (p65) and NLRP3 proteins were found in uninfected and HIV-1-infected macrophages. Likewise, no alterations were detected in ASC specks released in the culture supernatant after HIV-1 infection, suggesting that macrophages remain viable after infection. Using in silico prediction studies, we found that the HIV-1 proteins Gag and Vpr interact with several host proteins. Comparable levels of trans-LTB4 were found in the supernatants of uninfected and HIV-1-infected macrophages, whereas ROS production was impaired in infected cells, which was not reversed after the PMA stimulus. Immunofluorescence analysis showed structural alterations in the mitochondrial architecture and an increase of BIM in the cytoplasm of infected cells. Our data suggest that HIV-1 proteins Gag and Vpr, through interacting with cellular proteins in the early steps of infection, preclude the inflammasome activation and the development of effective immune responses, thus allowing the establishment of the infection.

Data-driven computational intelligence applied to dengue outbreak forecasting: a case study at the scale of the city of Natal, RN-Brazil.

Dengue is recognized as a health problem that causes significant socioeconomic impacts throughout the world, affecting millions of people each year. A commonly used method for monitoring the dengue vector is to count the eggs that Aedes aegypti mosquitoes have laid in spatially distributed ovitraps. Given this approach, the present study uses a database collected from 397 ovitraps allocated across the city of Natal, RN-Brazil. The Egg Density Index for each neighborhood was computed weekly, over four complete years (from 2016 to 2019), and simultaneously analyzed with the dengue case incidence. Our results illustrate that the incidence of dengue is related to the socioeconomic level of the neighborhoods in the city of Natal. A deep learning algorithm was used to predict future dengue case incidence, either based on the previous weeks of dengue incidence or the number of eggs present in the ovitraps. The analysis reveals that ovitrap data allows earlier prediction (four to six weeks) compared to dengue incidence itself (one week). Therefore, the results validate that the quantification of Aedes aegypti eggs can be valuable for the early planning of public health interventions.

Stochastic Petri net model describing the relationship between reported maternal and congenital syphilis cases in Brazil.

INTRODUCTION: Syphilis is a sexually transmitted disease (STD) caused by Treponema pallidum subspecies pallidum. In 2016, it was declared an epidemic in Brazil due to its high morbidity and mortality rates, mainly in cases of maternal syphilis (MS) and congenital syphilis (CS) with unfavorable outcomes. This paper aimed to mathematically describe the relationship between MS and CS cases reported in Brazil over the interval from 2010 to 2020, considering the likelihood of diagnosis and effective and timely maternal treatment during prenatal care, thus supporting the decision-making and coordination of syphilis response efforts. METHODS: The model used in this paper was based on stochastic Petri net (SPN) theory. Three different regressions, including linear, polynomial, and logistic regression, were used to obtain the weights of an SPN model. To validate the model, we ran 100 independent simulations for each probability of an untreated MS case leading to CS case (PUMLC) and performed a statistical t-test to reinforce the results reported herein. RESULTS: According to our analysis, the model for predicting congenital syphilis cases consistently achieved an average accuracy of 93% or more for all tested probabilities of an untreated MS case leading to CS case. CONCLUSIONS: The SPN approach proved to be suitable for explaining the Notifiable Diseases Information System (SINAN) dataset using the range of 75-95% for the probability of an untreated MS case leading to a CS case (PUMLC). In addition, the model's predictive power can help plan actions to fight against the disease.

miRNAs as biomarkers for early cancer detection and their application in the development of new diagnostic tools.

Over the last decades, microRNAs (miRNAs) have emerged as important molecules associated with the regulation of gene expression in humans and other organisms, expanding the strategies available to diagnose and handle several diseases. This paper presents a systematic review of literature of miRNAs related to cancer development and explores the main techniques used to quantify these molecules and their limitations as screening strategy. The bibliographic research was conducted using the online databases, PubMed, Google Scholar, Web of Science, and Science Direct searching the terms "microRNA detection", "miRNA detection", "miRNA and prostate cancer", "miRNA and cervical cancer", "miRNA and cervix cancer", "miRNA and breast cancer", and "miRNA and early cancer diagnosis". Along the systematic review over 26,000 published papers were reported, and 252 papers were returned after applying the inclusion and exclusion criteria, which were considered during this review. The aim of this study is to identify potential miRNAs related to cancer development that may be useful for early cancer diagnosis, notably in the breast, prostate, and cervical cancers. In addition, we suggest a preliminary top 20 miRNA panel according to their relevance during the respective cancer development. Considering the progressive number of new cancer cases every year worldwide, the development of new diagnostic tools is critical to refine the accuracy of screening tests, improving the life expectancy and allowing a better prognosis for the affected patients.

CCR2 Plays a Protective Role in Rocio Virus-Induced Encephalitis by Promoting Macrophage Infiltration Into the Brain.

Rocio virus (ROCV) is a highly neuropathogenic mosquito-transmitted flavivirus responsible for an unprecedented outbreak of human encephalitis during 1975-1976 in Sao Paulo State, Brazil. Previous studies have shown an increased number of inflammatory macrophages in the central nervous system (CNS) of ROCV-infected mice, implying a role for macrophages in the pathogenesis of ROCV. Here, we show that ROCV infection results in increased expression of CCL2 in the blood and in infiltration of macrophages into the brain. Moreover, we show, using CCR2 knockout mice, that CCR2 expression is essential for macrophage infiltration in the brain during ROCV infection and that the lack of CCR2 results in increased disease severity and mortality. Thus, our findings show the protective role of CCR2-mediated infiltration of macrophages in the brain during ROCV infection.

Epigenetic alterations are associated with monocyte immune dysfunctions in HIV-1 infection.

Monocytes are key cells in the immune dysregulation observed during human immunodeficiency virus (HIV) infection. The events that take place specifically in monocytes may contribute to the systemic immune dysfunction characterized by excessive immune activation in infected individuals, which directly correlates with pathogenesis and progression of the disease. Here, we investigated the immune dysfunction in monocytes from untreated and treated HIV + patients and associated these findings with epigenetic changes. Monocytes from HIV patients showed dysfunctional ability of phagocytosis and killing, and exhibited dysregulated cytokines and reactive oxygen species production after M. tuberculosis challenge in vitro. In addition, we showed that the expression of enzymes responsible for epigenetic changes was altered during HIV infection and was more prominent in patients that had high levels of soluble CD163 (sCD163), a newly identified plasmatic HIV progression biomarker. Among the enzymes, histone acetyltransferase 1 (HAT1) was the best epigenetic biomarker correlated with HIV - sCD163 high patients. In conclusion, we confirmed that HIV impairs effector functions of monocytes and these alterations are associated with epigenetic changes that once identified could be used as targets in therapies aiming the reduction of the systemic activation state found in HIV patients.

Classical and alternative macrophages have impaired function during acute and chronic HIV-1 infection

Abstract Objectives: Three decades after HIV recognition and its association with AIDS development, many advances have emerged – especially related to prevention and treatment. Undoubtedly, the development of Highly Active Antiretroviral Therapy (HAART) dramatically changed the future of the syndrome that we know today. In the present study, we evaluate the impact of Highly Active Antiretroviral Therapy on macrophage function and its relevance to HIV pathogenesis. Methods: PBMCs were isolated from blood samples and monocytes (CD14+ cells) were purified. Monocyte-Derived Macrophages (MDMs) were activated on classical (MGM-CSF+IFN-γ) or alternative (MIL-4+IL13) patterns using human recombinant cytokines for six days. After this period, Monocyte-Derived Macrophages were stimulated with TLR2/Dectin-1 or TLR4 agonists and we evaluated the influence of HIV-1 infection and Highly Active Antiretroviral Therapy on the release of cytokines/chemokines by macrophages. Results: The data were obtained using Monocyte-Derived Macrophages derived from HIV naïve or from patients on regular Highly Active Antiretroviral Therapy. Classically Monocyte-Derived Macrophages obtained from HIV-1 infected patients on Highly Active Antiretroviral Therapy released higher levels of IL-6 and IL-12 even without PAMPs stimuli when compared to control group. On the other hand, alternative Monocyte-Derived Macrophages derived from HIV-1 infected patients on Highly Active Antiretroviral Therapy released lower levels of IL-6, IL-10, TNF-α, IP-10 and RANTES after LPS stimuli when compared to control group. Furthermore, healthy individuals have a complex network of cytokines/chemokines released by Monocyte-Derived Macrophages after PAMP stimuli, which was deeply affected in MDMs obtained from naïve HIV-1 infected patients and only partially restored in MDMs derived from HIV-1 infected patients even on regular Highly Active Antiretroviral Therapy. Conclusion: Our therapy protocols were not effective in restoring the functional alterations induced by HIV, especially those found on macrophages. These findings indicate that we still need to develop new approaches and improve the current therapy protocols, focusing on the reestablishment of cellular functions and prevention/treatment of opportunistic infections.

Classical and alternative macrophages have impaired function during acute and chronic HIV-1 infection.

OBJECTIVES: Three decades after HIV recognition and its association with AIDS development, many advances have emerged - especially related to prevention and treatment. Undoubtedly, the development of Highly Active Antiretroviral Therapy (HAART) dramatically changed the future of the syndrome that we know today. In the present study, we evaluate the impact of Highly Active Antiretroviral Therapy on macrophage function and its relevance to HIV pathogenesis. METHODS: PBMCs were isolated from blood samples and monocytes (CD14+ cells) were purified. Monocyte-Derived Macrophages (MDMs) were activated on classical (MGM-CSF+IFN-γ) or alternative (MIL-4+IL13) patterns using human recombinant cytokines for six days. After this period, Monocyte-Derived Macrophages were stimulated with TLR2/Dectin-1 or TLR4 agonists and we evaluated the influence of HIV-1 infection and Highly Active Antiretroviral Therapy on the release of cytokines/chemokines by macrophages. RESULTS: The data were obtained using Monocyte-Derived Macrophages derived from HIV naïve or from patients on regular Highly Active Antiretroviral Therapy. Classically Monocyte-Derived Macrophages obtained from HIV-1 infected patients on Highly Active Antiretroviral Therapy released higher levels of IL-6 and IL-12 even without PAMPs stimuli when compared to control group. On the other hand, alternative Monocyte-Derived Macrophages derived from HIV-1 infected patients on Highly Active Antiretroviral Therapy released lower levels of IL-6, IL-10, TNF-α, IP-10 and RANTES after LPS stimuli when compared to control group. Furthermore, healthy individuals have a complex network of cytokines/chemokines released by Monocyte-Derived Macrophages after PAMP stimuli, which was deeply affected in MDMs obtained from naïve HIV-1 infected patients and only partially restored in MDMs derived from HIV-1 infected patients even on regular Highly Active Antiretroviral Therapy. CONCLUSION: Our therapy protocols were not effective in restoring the functional alterations induced by HIV, especially those found on macrophages. These findings indicate that we still need to develop new approaches and improve the current therapy protocols, focusing on the reestablishment of cellular functions and prevention/treatment of opportunistic infections.

HIV infection: focus on the innate immune cells.

Innate immune cells play a critical role during the onset of HIV infection and remain active until the final events that characterize AIDS. The viral impact on innate immune cell response may be a result of direct infection or indirect modulation, and each cell type responds in a specific manner to HIV. During HIV infection, the immune system works in a dynamic way, where innate and adaptive cells contribute with each other stimulating their function and modulating phenotypes and consequently infection resolution. Understanding the alterations in the cell populations induced by the virus is pivotal and can help to combat HIV at the time of infection and above all, to prevent the establishment of viral reservoirs. In this review, we will describe the frequency and the subtypes of infected cells such as of monocytes, DCs, neutrophils, eosinophils, mast cells/basophils, NK cells, NKT cells and γδ T cells, and we discuss the possibility of cell-targeting strategies. Our aim is to consolidate the existing knowledge of the interaction between HIV and cells that constitute the innate immune response.