Large-scale releases and establishment of wMel Wolbachia in Aedes aegypti mosquitoes throughout the Cities of Bello, Medellín and Itagüí, Colombia.

BACKGROUND: The wMel strain of Wolbachia has been successfully introduced into Aedes aegypti mosquitoes and has been shown to reduce the transmission of dengue and other Aedes-borne viruses. Here we report the entomological results from phased, large-scale releases of Wolbachia infected Ae. aegypti mosquitoes throughout three contiguous cities located in the Aburrá Valley, Colombia. METHODOLOGY/PRINCIPAL FINDINGS: Local wMel Wolbachia-infected Ae. aegypti mosquitoes were generated and then released in an initial release pilot area in 2015-2016, which resulted in the establishment of Wolbachia in the local mosquito populations. Subsequent large-scale releases, mainly involving vehicle-based releases of adult mosquitoes along publicly accessible roads and streets, were undertaken across 29 comunas throughout Bello, Medellín and Itagüí Colombia between 2017-2022. In 9 comunas these were supplemented by egg releases that were undertaken by staff or community members. By the most recent monitoring, Wolbachia was found to be stable and established at consistent levels in local mosquito populations (>60% prevalence) in the majority (67%) of areas. CONCLUSION: These results, from the largest contiguous releases of wMel Wolbachia mosquitoes to date, highlight the operational feasibility of implementing the method in large urban settings. Based on results from previous studies, we expect that Wolbachia establishment will be sustained long term. Ongoing monitoring will confirm Wolbachia persistence in local mosquito populations and track its establishment in the remaining areas.

Moderating Effect of the Situation of Return or Relocation on the Well-Being and Psychosocial Trauma of Young Victims of the Armed Conflict in Colombia.

Colombia is the second country with the highest number of internally displaced persons. In the last 10 years, more than 400,000 young people carry, in their life experiences, the title of victims. The psychological and social circumstances that determine the lives of displaced young people in the world are not unknown. Fear, the poor resources for social adaptation available to them, and the possible reproduction of the cycle of violence, represent psychosocial risk factors in the young and displaced population. In this context, the Victims Law in Colombia stipulated various measures of repairment, including Relocation (the person or household victim of forced displacement decides to settle in some place, other than the one they were forced to leave) and Return (the person or the household victim of forced displacement decides to return to the place from which they were displaced, in order to settle indefinitely) provided the conditions of voluntariness, security, and dignity are present. A hypothesis that well-being will be better in the returnees was set, since they would strengthen the social support networks between neighbors and other victims in their old spaces of life. To test the hypothesis, the scales of Psychological Well-being, Social Well-being, the Satisfaction with Life Scale, and the Psychosocial Trauma Scale were applied to young returnees (n = 129) and relocated (n = 259) in Colombia. The Exploratory and Confirmatory Factor Analysis was performed to extract the general measure of well-being and psychosocial trauma followed by the comparison between the groups. Significance, power, and effect size indicators were obtained, and finally, the partial correlation between the groups was made in relation to psychosocial trauma and well-being. Results showed that returnees have greater well-being and clearer indicators (d = 0.365, 1-ß = 0.996), with respect to that of relocated. In addition, the well-being of returnees has fewer trauma factors, who in turn are quasi-moderated by the situation of return or relocation.

Role of Different Subpopulations of CD8+ T Cells during HIV Exposure and Infection.

During HIV infection, specific responses exhibited by CD8+ T cells are crucial to establish an early, effective, and sustained viral control, preventing severe immune alterations and organ dysfunction. Several CD8+ T cells subsets have been identified, exhibiting differences in terms of activation, functional profile, and ability to limit HIV replication. Some of the most important CD8+ T cells subsets associated with viral control, production of potent antiviral molecules, and strong polyfunctional responses include Th1-like cytokine pattern and Tc17 cells. In addition, the expression of specific activation markers has been also associated with a more effective response of CD8+ T cells, as evidenced in HLA-DR+ CD38- cells. CD8+ T cells in both, peripheral blood and gut mucosa, are particularly important in individuals with a resistant phenotype, including HIV-exposed seronegative individuals (HESNs), long-term non-progressors (LTNPs) and HIV-controllers. Although the role of CD8+ T cells has been extensively explored in the context of an established HIV-1 infection, the presence of HIV-specific cells with effector abilities and a defined functional profile in HESNs, remain poorly understood. Here, we reviewed studies carried out on different subpopulations of CD8+ T cells in relation with natural resistance to HIV infection and progression.

Role of Regulatory T Cells and Inhibitory Molecules in the Development of Immune Exhaustion During Human Immunodeficiency Virus Type 1 Infection.

One of the key hallmarks of chronic human immunodeficiency virus type 1 (HIV-1) infection is the persistent immune activation triggered since early stages of the infection, followed by the development of an exhaustion phenomena, which leads to the inability of immune cells to respond appropriately to the virus and other pathogens, constituting the acquired immunodeficiency syndrome (AIDS); this exhausting state is characterized by a loss of effector functions of immune cells such as proliferation, production of cytokine, as well as cytotoxic potential and it has been attributable to an increased response of regulatory T cells and recently also to the expression in different cell populations of inhibitory molecules, such as programmed death receptor-1 (PD-1), cytotoxic T lymphocyte antigen-4 (CTLA-4), T cell immunoglobulin-3 (Tim-3), and lymphocyte activation gene-3 (LAG-3). The importance of these molecules relies on the possibility to restore the immune response once these molecules are blocked, constituting a potential therapeutic target for treatment during HIV infection. In this regard, we explored the available data evaluating the functional role of Treg cells and inhibitory molecules during the infection in both blood and gut-associated lymphoid tissue (GALT) and their contribution to the development of immune exhaustion and progression to AIDS, as well as their therapeutic potential.

High Expression of Antiviral Proteins in Mucosa from Individuals Exhibiting Resistance to Human Immunodeficiency Virus.

BACKGROUND: Several soluble factors have been reported to have the capacity of inhibiting HIV replication at different steps of the virus life cycle, without eliminating infected cells and through enhancement of specific cellular mechanisms. Yet, it is unclear if these antiviral factors play a role in the protection from HIV infection or in the control of viral replication. Here we evaluated two cohorts: i) one of 58 HIV-exposed seronegative individuals (HESNs) who were compared with 59 healthy controls (HCs), and ii) another of 13 HIV-controllers who were compared with 20 HIV-progressors. Peripheral blood, oral and genital mucosa and gut-associated lymphoid tissue (GALT) samples were obtained to analyze the mRNA expression of ELAFIN, APOBEC3G, SAMHD1, TRIM5α, RNase 7 and SerpinA1 using real-time PCR. RESULTS: HESNs exhibited higher expression of all antiviral factors in peripheral blood mononuclear cells (PBMCs), oral or genital mucosa when compared with HCs. Furthermore, HIV-controllers exhibited higher levels of SerpinA1 in GALT. CONCLUSIONS: These findings suggest that the activity of these factors is compartmentalized and that these proteins have a predominant role depending on the tissue to avoid the infection, reduce the viral load and modulate the susceptibility to HIV infection.

Higher Frequency of NK and CD4+ T-Cells in Mucosa and Potent Cytotoxic Response in HIV Controllers.

HIV infection induces immune alterations, mainly in gut mucosa, where the main target cells reside. However, the evolution of the infection is variable among infected individuals, as evidenced by HIV controllers who exhibit low or undetectable viral load in the absence of treatment. The aim of this study was to evaluate the frequency, phenotype and activity of T and NK cells in peripheral blood and gut mucosa in a cohort of Colombian HIV controllers. Blood and gut biopsies were included. The frequency and the activation status of T and NK cells were performed by flow cytometry. In addition, Gag-stimulated CD8+ T-cells and cytokine-stimulated NK cells were tested for cytotoxic activity. Finally, microbial translocation was measured by plasma lipopolysaccharide quantification. Compared with HIV-progressors, HIV controllers exhibited higher frequency of CD4+ T and NK cells, and lower expression of activation molecules in blood and mucosal immune cells, as well as lower microbial translocation. An increased production of molecules associated with cytotoxic activity of CD8+ T-cells in blood and mucosa and a higher percentage of polyfunctional CD8+ T cells in blood were also observed in HIV controllers. In addition, an increased activity of NK cells was observed in blood. These findings suggest that HIV controllers have a potent immune response, mainly mediated by cytotoxic cells that control HIV replication, which contribute to reducing alterations at the gut mucosa.

Arteries of the thumb: description of anatomical variations and review of the literature.

BACKGROUND: Vascular studies of the thumb have reported conflicting results; even the anatomical nomenclature differs between studies. The main purpose of this study was to describe the local patterns of thumb vascular anatomy. METHODS: The authors studied 30 fresh right hands from male and female cadavers using a vascular injection technique with methyl methacrylate. The origins, course, and characteristics of the arteries of the thumb are described. RESULTS: The princeps pollicis artery was present in all of the hands and was the origin of the radial and ulnar digital arteries in 73.3 percent. The radial and ulnar digital arteries originated from the princeps pollicis artery or branches of the palmar metacarpal artery in 53.3 and 83.3 percent of the dissections, respectively. Dorsally, the dorsal ulnar artery was present in 100 percent of the hands and originated mainly from the princeps pollicis artery (73.3 percent). The dorsal radial artery was present in 66.7 percent of dissections as a direct branch of the radial artery. Several anastomoses were observed between the radial and ulnar digital arteries and between the dorsal and palmar systems. CONCLUSIONS: Various arterial systems were described in the arterial irrigations of the thumb, such as the dorsopalmar and radioulnar. The complex configuration and the multiple anastomotic arcades between the arterial systems allow the thumb to survive even after severe lesions of nearly all of the arteries. The presence of these interconnected systems provides multiple alternatives in flap design without endangering their survival.

Factores familiares y sociales de alto riesgo asociados al trabajo infantil en ciudades de la Costa Caribe colombiana / High risk family and social factors associated with child labour in cities of the colombian caribbean coast

Se describen los factores familiares y sociales de alto riesgo asociados al trabajo infantil. La muestra, de carácter intencional, estuvo constituida por 835 niños, niñas y adolescentes entre 6 y 17 años (M = 10.6 años y DE = 2.2) de las ciudades de Barranquilla, Santa Marta y Cartagena, que participaron en el proyecto "Edúcame primero, Colombia" durante 2008. Los resultados presentan datos relevantes sobre el estado sociodemográfico de los niños participantes, sus características familiares y condiciones sociales, que permitirán establecer una línea base actualizada y abrir camino para la construcción de estrategias de intervención efectivas sobre un flagelo que azota a los niños, niñas y jóvenes no solo de Colombia, sino del mundo.

The investigation describes the familiar and social factors of high risk associated with child labour. The sample of intentional character, was made up of 835 children and teenagers between 6 and 17 years (average of 10.6 years and DT = 2.2) of the cities of Barranquilla, Santa Marta, and Cartagena, which participated in the project "Educate First Your Colombia "during the year 2008. The results presented relevant data on the State population partner participating children, familiar characteristics and social conditions, to help establish a baseline updated and pave way for the construction of effective intervention strategies on a scourge that flogs the children and young people not only of Colombia but worldwide.