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Se reportan los primeros registros de dos especies de hormigas, i.e., Hypoponera opacior y Pseudomyrmex seminole y dos géneros, i.e., Acanthosticus y Mycetosoritis (Hymenoptera: Formicidae), asociados a etapas de descomposición de necrotrampas colocadas en una zona semiurbana del estado de Yucatán, México.

The silverleaf whitefly (Bemisia tabaci) is the most harmful pest for vegetables in tropical zones. One alternative for its ecological management is the use of repellent aromatic plants. The hypothesis of this study is that the aromatic plants that diminish the attraction of B. tabaci to tomato have the capacity to prevent the infestation of this pest in the tomato crop when an intercropping system of tomato-aromatic plant is established. The objective of this study was to evaluate by means of the technique of olfactometry, the response of B. tabaci to the volatiles emitted by the crushed leaves of tomato and by the combination tomato + aromatic plant. The aromatic plants with highest activity in the olfactometry tests were intercropped in a tomato crop in the field. In the bioassays of olfactometry, a significant decrease was observed in the attraction of B. tabaci to crushed leaves of tomato + some aromatic plants compared with the attraction to tomato alone. The repellence indices (IR) showed that the aromatics Lavandula angustifolia Mill. (IR, 0.1), Petiveria alliacea L. (IR, 0.48), Petroselinum crispum Mill. (IR, 0.28) and Thymus vulgaris (IR, 0.5) had the greatest effect as repellent of adults. By integrating these aromatic species through intercropping in the tomato field crop, no significant difference was observed in the population density of eggs and adults of B. tabaci in the tomato foliage in regard to what was observed in the control (only tomato). The incidence and severity of viral symptoms did not decrease from the presence of the aromatic species intercropped in the tomato crop.

Objective Short-read next-generation sequencing (NGS) has been implemented to study the resistance profile of HIV as it provides a higher sensitivity than Sanger sequencing. However, short-reads only generates a consensus view of the viral population rather than a reconstruction of the viral haplotypes. In this study, we evaluated the resistance profile of HIV quasispecies in patients undergoing treatment failure using SMRT sequencing. Design Whole-pol RT-PCR was performed on viral RNA extracted from plasma samples of 38 HIV-positive individuals undergoing treatment failure, and sequenced in the RSII instrument. Error correction and viral haplotype phasing was performed with the Multilayer Directed Phasing and Sequencing (MDPSeq) algorithm. Presence of resistance mutations reported by the IAS-USA in 2017 was assessed using an in-house script. Results The SMRT sequencing-based test detected 131/134 resistance mutations previously detected using a Sanger sequencing-based test. However, the SMRT test also identified seven additional mutations present at an estimated frequency lower than 30%. The intra-host phylogenetic analysis showed that seven samples harbored at least one resistance variant at 20--80% frequency. The haplotype-resolved sequencing revealed viral diversification and selection of new resistance during suboptimal treatment, an overall trend toward selection and accumulation of new resistance mutations, as well as the co-existence of resistant and susceptible variants. Conclusion Our results validate the SMRT sequencing-based test for detection of HIV drug resistance. In addition, this method unraveled the complex dynamic of HIV quasispecies during treatment failure, which might have several implications on clinical management.

Background. The use of biostimulants is an alternative to improve the growth and productivity of horticultural crops. Objective. To evaluate the effect of three biostimulants (seaweed extracts, humic acids and amino acids) on the plant growth, foliar characteristics, and population density of Bemisia tabaci in habanero pepper plants (Capsicum chinense). Methodology. The biostimulants were applied to the plant growth substrate in seedling and in pot plants. The response variables were plant growth, leaf thickness and toughness, leaf area and population density of B. tabaci. Results. Humic acids promoted the number of leaves and stem thickness in seedlings. The thickness of the leaves was stimulated by seaweed extract and humic acids and the leaf area by amino acids. The biostimulants had no effect on the response of the plants to the population density of B. tabaci. Implication. The use of biostimulants in habanero pepper plants could enhance plant growth in specific growth phases. Conclusion. The use of biostimulants in habanero pepper plants did not show consistent effects on plant growth promotion in habanero pepper. There were no effects of the biostimulants on the induction of plant defense to B. tabaci in habanero pepper.

Se desconoce si las personas que viven con el VIH (PVV) tienen un mayor riesgo de contraer la infección por SARS-CoV-2. Los estudios serológicos prospectivos pueden permitir análisis de seroincidencia. Este estudio prospectivo incluyó a PVV, sin antecedentes de vacunación contra SARS-CoV-2, de la Ciudad Autónoma de Buenos Aires (CABA) y Gran Buenos Aires (GBA) que concurrieron entre marzo y junio de 2021 a realizar sus controles al Instituto INBIRS. La tasa de seroprevalencia de anticuerpos contra la proteína espiga del SARS-CoV-2 fue del 33.3% (IC 24.9-42.5%) para la población estudiada. Esta prevalencia fue significativamente mayor a la reportada previamente para la población general de la misma región geográfica. No se observó una asociación entre el recuento de linfocitos T CD4+ con los niveles de IgG especifica. En conclusión, el hallazgo de una alta seroprevalencia de anticuerpos contra SARS-CoV-2 entre las PVV en CABA y GBA pueden sugerir una mayor susceptibilidad a la infección por este virus; sin embargo, puede ser también un marcador subrogante que la tasa de seroprevalencia en población general se encuentra subestimada.

BACKGROUND: The persistence of latently infected T cells remains the principal barrier to HIV cure. Understanding how the early immune responses shape persistence of HIV on antiretroviral therapy (ART) will be fundamental for potential eradication. Here, we aimed to determine the relationship between CD8 T-cell function and phenotype before therapy and HIV persistence on ART. METHODS: Blood samples from 29 individuals enrolled during primary HIV infection (at baseline and every 3 months up to 2 years post-ART initiation) were obtained. HIV-specific T-cell function and expression of the activation markers were evaluated before ART by flow cytometry. Cell-associated HIV DNA and unspliced (US)-RNA were quantified in purified CD4 T cells by real-time polymerase chain reaction. Data were analyzed using nonparametric statistics. RESULTS: Elevated immune activation, dominance of monofunctional CD8 T cells, and skewed distribution of memory profile were observed before ART. After ART initiation, HIV DNA and US-RNA levels rapidly diminished, reaching a plateau by 30 weeks after ART. The proportion of baseline HIV-specific effector memory and terminal effector CD8 T cells directly correlated with HIV DNA levels at 1 year after ART. A strong positive correlation was observed between the proportion of bulk and HIV-specific PD-1 CD8 T cells measured before ART and HIV DNA at 1 year after ART. CONCLUSIONS: A higher proportion of terminally differentiated CD8 T cells and increased PD1 expression were associated with HIV persistence on ART after treatment of primary infection. Thus, the quality of the early CD8 T-cell immune response may serve as a predictor of HIV persistence on ART.

La pandemia de COVID-19 ha puesto en jaque a los sistemas de salud en el mundo; la vinculación entre la investigación biomédica y la práctica asistencial ha probado ser un requisito fundamental para dar respuesta a la misma de manera eficiente y rápida. En este sentido, los biobancos se constituyen como un componente clave ya que favorecen el almacenamiento de grandes volúmenes de muestras biológicas gestionadas en base a criterios que garanticen su óptima calidad, armonización y seguridad, respetando requisitos éticos y legales que aseguran los derechos de los ciudadanos. La cesión de estas muestras a distintos grupos de investigación promueve el desarrollo de nuevas herramientas diagnósticas y terapéuticas y vacunas. Frente a la llegada del SARS-CoV-2 a la Argentina, el Biobanco de Enfermedades Infecciosas estableció rápidamente la colección COVID-19 constituida por muestras de plasma, suero y células mononucleares de sangre periférica de personas cursando la enfermedad o recuperadas. En solo seis meses se enrolaron 825 donantes, lo que significa alrededor de 14.000 viales de material biológico almacenados y a disposición de los investigadores que lo soliciten. A tal efecto, se realizaron seis actos de cesión a diversos grupos pertenecientes a instituciones de investigación, mientras que tres se encuentran en evaluación. Las muestras cedidas han permitido, por ejemplo, el desarrollo de kits serológicos de producción nacional; lo que pone de manifiesto que el rápido establecimiento de esta colección, bajo un sistema de gestión eficiente, constituye una herramienta muy valiosa en la respuesta a esta nueva enfermedad.

Background Hepatitis C virus (HCV) coinfection among people with human immunodeficiency virus (HIV) might perturb immune function and HIV persistence. We aimed to evaluate the impact of HCV clearance with direct-acting antivirals (DAAs) on immune activation and HIV persistence in HIV/HCV-coinfected individuals on antiretroviral therapy (ART). Methods In a prospective observational study, ART-treated participants with HIV/HCV coinfection received sofosbuvir/daclatasvir ± ribavirin (n = 19). Blood samples were collected before DAA therapy, at the end of treatment, and 12 months after DAA termination (12MPT). T- and natural killer (NK)-cell phenotype, soluble plasma factors, cell-associated (CA)-HIV deoxyribonucleic acid (DNA) forms (total, integrated, 2LTR), CA-unspliced (US) and multiple-spliced ribonucleic acid (RNA), and plasma HIV RNA were evaluated. Results Hepatitis C virus clearance was associated with (1) a downmodulation of activation and exhaustion markers in CD4+, CD8+ T, and NK cells together with (2) decreased plasma levels of Interferon gamma-induced protein 10 (IP10), interleukin-8 (IL-8), soluble (s)CD163 and soluble intercellular adhesion molecule (sICAM). Cell-associated US HIV RNA was significantly higher at 12MPT compared to baseline, with no change in HIV DNA or plasma RNA. Conclusions Elimination of HCV in HIV/HCV-coinfected individuals alters immune function and the transcriptional activity of latently infected cells. This report provides insights into the effects of HCV coinfection in HIV persistence and regards coinfected subjects as a population in which HIV remission might prove to be more challenging., This article addresses the immediate and long-term effects of direct-acting antiviral-mediated HCV clearance on the HIV reservoir dynamics and immune function, in a cohort of HIV/HCV-coinfected individuals under antiretroviral treatment.

Background. The whitefly Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae) is a pest that causes significant losses in field and greenhouse crops worldwide. Objective. To evaluate the incorporation of biorational and chemical insecticides on the population density of whitefly Bemisia tabaci, fruit yield and fruit quality in tomato. Methodology. Three pest management treatments were included: Biorational (botanical insecticides and insect growth regulators), Biorational-Intermediate (botanical insecticide and chemical insecticides) and Conventional (conventional chemical insecticides). Results. Overall, the population density of B. tabaci was low from the time when the pest-exclusion floating net was removed to the sampling periods 61 to 78 days after transplant (dat). However from 92 to 108 dat, the population density of inmature and adults increased dramatically. The treatment Conventional was the most effective to supress the population density of B. tabaci when they were low, but when an increase in population density of B. tabaci ocurred, the treatment Biorational-Intermediate was the most effective. The population density of eggs and nymphs on plant leaves were similar among treatments. The fruit yield and overall the bromatologic characteristics of fruits were not significantly different among treatments. Conclusion. The treatment Biorational-Intermediate would represent a feasible strategy to manage Bemisia tabaci in tomato crops.

Background Mycobacterium tuberculosis (Mtb) is the causative agent of tuberculosis (TB), affecting approximately one third of the world’s population. Development of an adequate immune response will determine disease progression or progress to chronic infection. Risk of developing TB among human immunodeficiency virus (HIV)-coinfected patients (HIV-TB) is 20–30 times higher than those without HIV infection, and a synergistic interplay between these two pathogens accelerates the decline in immunological functions. TB treatment in HIV-TB coinfected persons is challenging and it has a prolonged duration, mainly due to the immune system failure to provide an adequate support for the therapy. Therefore, we aimed to study the role of the hormone 7-oxo-dehydroepiandrosterone (7-OD) as a modulator of anti-tuberculosis immune responses in the context of HIV-TB coinfection. Methods A cross-sectional study was conducted among HIV-TB patients and healthy donors (HD). We characterized the ex vivo phenotype of CD4 + T cells and also evaluated in vitro antigen-specific responses by Mtb stimulation of peripheral blood mononuclear cells (PBMCs) in the presence or absence of 7-OD. We assessed lymphoproliferative activity, cytokine production and master transcription factor profiles. Results Our results show that HIV-TB patients were not able to generate successful anti-tubercular responses in vitro compared to HD, as reduced IFN-γ/IL-10 and IFN-γ/IL-17A ratios were observed. Interestingly, treatment with 7-OD enhanced Th1 responses by increasing Mtb-induced proliferation and the production of IFN-γ and TNF-α over IL-10 levels. Additionally, in vitro Mtb stimulation augmented the frequency of cells with a regulatory phenotype, while 7-OD reduced the proportion of these subsets and induced an increase in CD4 + T-bet+ (Th1) subpopulation, which is associated with clinical data linked to an improved disease outcome. Conclusions We conclude that 7-OD modifies the cytokine balance and the phenotype of CD4 + T cells towards a more favorable profile for mycobacteria control. These results provide new data to delineate novel treatment approaches as co-adjuvant for the treatment of TB.

During the acute phase of HIV-1 infection, a strong readaptation occurs in the viral population. Our objective was to analyze the post-transmission mutations associated with escape to the cytotoxic immune response and its relationship with the progression of the infection. In this study, a total of 17 patients were enrolled during acute/early primary HIV infection and 8 subjects that were the HIV positive partner resulting in 8 transmission pairs. Genotyping of the genetic polymorphisms of HLA class I A and B was performed using PCR-SSOP. Viral RNA extraction was from plasma. 570 single Gag-gene amplifications were obtained by limiting-dilution RT-PCR. Epitope prediction was performed with NetMHC CBS prediction server for the 19 HLA-A and [sbnd]B alleles. Cytotoxic response prediction was performed by using the IEDB Analysis Resource. From our results, we deduce that the transmitted CTL / gag escape frequency in the founder virus was at least double compared to the post-transmission events. Additionally, by means of an algorithm that combines these frequencies, we observed that the founder viruses better adapted to the HLA A / B alleles of the recipient could contribute to a greater progression of the infection. Our results suggest that there is a large adaptation of HIV-1 to the HLA A / B alleles prevalent in our population. However, despite this adaptive advantage, the virus needs to make “readjustments” through new escape and compensatory mutations. Interestingly, according to our results, this readaptation could have a role in the progression of the infection. Fil: Damilano, Gabriel Dario. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Sued, Omar Gustavo. Fundación Huésped; Argentina Fil: Satorres, Sara Elena. Universidad Nacional de San Luis; Argentina Fil: Ruiz, M.J.. University of Montreal; Canadá Fil: Ghiglione, Yanina Alexandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Guzman, F.. Pontificia Universidad Católica de Valparaíso; Chile Fil: Turk, Gabriela Julia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Quiroga, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Cahn, Pedro. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Salomon, Horacio Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Dilernia, D.. University of Emory; Estados Unidos

The aim of this study was to evaluate the effectiveness of antiretroviral treatment (ART) on the proportion and functions of Th17 and Treg cells in peripheral blood and female genital tract (FGT) respectively. To this aim, samples from 41 HIV-neg, 33 HIV+ ART-naïve and 32 HIV+ ART+ subjects were obtained. In peripheral blood, altered Th17 and Th17/Treg proportions were normalized in HIV+ ART+, but certain abnormal Treg and activated T-cell proportions were still observed. In FGT, abnormal patterns of secretion for Th17-related cytokines were observed in cervical mononuclear cells (CMCs) from HIV+ women, even in those from HIV+ ART+, compared to the HIV-neg group. Moreover, these altered patterns of secretion were associated with diminished levels of CXCL5 and CXCL1 chemokines and with an immunoregulatory skew in the CCL17/CCL20 ratio in ectocervix samples of these women. Finally, ART did not restore proportions of Th17-precursor cells with gut-homing potential in PBMCs, and positive correlations between these cells and the levels of IL-17F and IL-21 production by CMCs may suggest that a better homing of these cells to the intestine could also imply a better restoration of these cells in the female genital tract. These results indicate that antiretroviral treatment did not restore Th17-related immune functions completely at the female mucosal level. Fil: Caruso, María Paula. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Falivene, Juliana. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Holgado, María Pía. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Zurita, Diego Hernán(EXT). Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Laufer, Natalia Lorna. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Castro, Carina Lorena. Centro Médico Accord; Argentina Fil: Nico, Ángeles. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Maeto, Cynthia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Salido, Jimena Patricia. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Perez, Hector. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina Fil: Acevedo González, Horacio Anselmo. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Cahn, Pedro. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina. Fundación Huésped; Argentina Fil: Sued, Omar Gustavo. Fundación Huésped; Argentina Fil: Fink, Valeria Irene. Gobierno de la Ciudad de Buenos Aires. Hospital General de Agudos "Juan A. Fernández"; Argentina. Fundación Huésped; Argentina Fil: Turk, Gabriela Julia Ana. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Gherardi, Maria Magdalena. Universidad de Buenos Aires; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Elucidating the factors that modulate HIV-specific antibody-dependent cellular cytotoxicity (ADCC) will help in understanding its role in HIV immunity. The aim of this study was to determine whether IgA could modify the magnitude of ADCC in HIV infection, abrogating its protective role. Plasma samples from 20 HIV-positive (HIV + ) subjects enrolled during primary HIV infection (PHI), 10 chronically infected subjects (chronic), and 7 elite controllers (EC) were used. ADCC was determined by using a fluorometric ADCC assay, before and after removal of plasma IgA. Data were analyzed by using nonparametric statistics. ADCC was documented in 80% of PHI enrollment samples and in 100% of PHI 12-month, chronic, and EC samples; it peaked after acute infection, reached a plateau in chronic infection, and decreased after initiation of antiretroviral treatment (ART). Significant associations between ADCC and disease progression were found only after removal of plasma IgA from 12-month PHI samples: the magnitude of ADCC not only increased after IgA removal but also correlated with CD4 + T-cell preservation. This work provides evidence that gp120-specific IgA was capable of modifying ADCC responses during natural HIV infection for the first time and adds to similar evidence provided in other settings. Furthermore, it underscores the complexity of the ADCC phenomenon and will help in an understanding of its underlying mechanisms. IMPORTANCE Although the induction of ADCC-mediating antibodies in HIV-infected subjects has been extensively documented, the association of these antibodies with protection from disease progression is poorly understood. Here, we demonstrate that plasma IgA is a factor capable of modifying the magnitude of IgG-mediated ADCC in HIV infection, mitigating its beneficial effect. These results help in understanding why previous studies failed to demonstrate correlations between ADCC and disease progression, and they also contribute to the notion that an HIV vaccine should stimulate the production of ADCC-mediating IgG antibodies but not IgA.

In order to identify the role played by plant species as a food source in the fruit election of dispersing agents (Alouatta pigra Lawrence 1933, Atelesgeoffroyi Kuhl 1820 and frugivorous bats), we developed a study in dry tropical forests in Yucatan, Mexico. We recorded the fruits consumed by frugivorous bats using collectors and, for monkeys, we implemented the focal animal method. The number of fruits consumed by primates (A. pigra and A. geoffroyi) and bats were recorded, 342 and 386, respectively. It was determined that bats deposited fruits with some percentage of pulp, while monkeys contributed more with a fruits without pulp (pairwise LSD contrast p < 0.05). Among the variety of fruit species in the diet of primates, we detected that A. pigra chose mostly not an abundant species such as Enterolobium cyclocarpum Jacq. Griseb. (1860) instead of those more abundant (Manilkara zapota (L.) P. Royen (1953) and Brosimum alicastrum Sw. subsp. alicastrum C.C. Berg (1972)). The type of fruit and seed handling caused by primates would be more beneficial to seed germination than those applied by bats. Moreover, this election and fruit handling could depend on the characteristics of fruits and space-temporal availability of plant species as a food source. RESUMEN Con el objetivo de examinar el papel que juegan las especies vegetales como fuentes alimenticias en la selección de frutos de agentes dispersores (Alouatta pigra, Ateles geoffroyi y murciélagos frugívoros), se realizó un estudio en selvas secas en el sureste de Yucatán, México. Se registraron los frutos consumidos por murciélagos usando colectores y, en el caso de los monos, se implementó el método de animal focal. El número de frutos consumidos registrados para ambas especies de primates y murciélagos fueron 342 y 386, respectivamente. Se determinó que los murciélagos depositaron frutos con pequeñas cantidades de pulpa, mientras que los monos contribuyeron mayormente con frutos totalmente despulpados (contrastes por pares LSD p < 0.05). Entre la variedad de especies de frutos en la dieta de los primates se detectó que A. pigra eligió frutos de las especies menos abundantes como Enterolobium cyclocarpum Jacq. Griseb. (1860) en vez de aquellas más abundantes (Manilkara zapota (L.) P. Royen (1953) y Brosimum alicastrum Sw. subsp. alicastrum C.C. Berg (1972)). El tipo de manejo de frutos y semillas causado por los primates sería más beneficioso para la germinación de las semillas que los aplicados por los murciélagos. Además, esta elección y manejo del fruto podría depender de sus características y la disponibilidad espacio-temporal de las especies de plantas como fuente de alimento.

Understanding the mechanisms of human immunodeficiency virus type I (HIV-1) pathogenesis would facilitate the identification of new therapeutic targets to control the infection in face of current antiretroviral therapy limitations. CD74 membrane expression is upregulated in HIV-1-infected cells and the magnitude of its modulation correlates with immune hyperactivation in HIV-infected individuals. In addition, plasma level of the CD74 activating ligand macrophage migration inhibitory factor (MIF) is increased in infected subjects. However, the role played by MIF/CD74 interaction in HIV pathogenesis remains unexplored. Here, we studied the effect of MIF/CD74 interaction on primary HIV-infected monocyte-derived macrophages (MDMs) and its implications for HIV immunopathogenesis. Confocal immunofluorescence analysis of CD74 and CD44 (the MIF signal transduction co-receptor) expression indicated that both molecules colocalized at the plasma membrane specifically in wild-type HIV-infected MDMs. Treatment of infected MDMs with MIF resulted in an MIF-dependent increase in TLR4 expression. Similarly, there was a dose-dependent increase in the production of IL-6, IL-8, TNFα, IL-1β, and sICAM compared to the no-MIF condition, specifically from infected MDMs. Importantly, the effect observed on IL-6, IL-8, TNFα, and IL-1β was abrogated by impeding MIF interaction with CD74. Moreover, the use of a neutralizing αMIF antibody or an MIF antagonist reverted these effects, supporting the specificity of the results. Treatment of unactivated CD4+ T-cells with MIF-treated HIV-infected MDM-derived culture supernatants led to enhanced permissiveness to HIV-1 infection. This effect was lost when CD4+ T-cells were treated with supernatants derived from infected MDMs in which CD74/MIF interaction had been blocked. Moreover, the enhanced permissiveness of unactivated CD4+ T-cells was recapitulated by exogenous addition of IL-6, IL-8, IL-1β, and TNFα, or abrogated by neutralizing its biological activity using specific antibodies. Results obtained with BAL and NL4-3 HIV laboratory strains were reproduced using transmitted/founder primary isolates. This evidence indicated that MIF/CD74 interaction resulted in a higher production of proinflammatory cytokines from HIV-infected MDMs. This caused the generation of an inflammatory microenvironment which predisposed unactivated CD4+ T-cells to HIV-1 infection, which might contribute to viral spreading and reservoir seeding. Overall, these results support a novel role of the MIF/CD74 axis in HIV pathogenesis that deserves further investigation. Fil: Trifone, César Ariel. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Salido, Jimena Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Ruiz, María Julia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Leng, Lin. University of Yale; Estados Unidos Fil: Quiroga, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Salomon, Horacio Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Bucala, Richard. University of Yale; Estados Unidos Fil: Ghiglione, Yanina Alexandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina Fil: Turk, Gabriela Julia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Investigaciones Biomédicas en Retrovirus y Sida. Universidad de Buenos Aires. Facultad de Medicina. Instituto de Investigaciones Biomédicas en Retrovirus y Sida; Argentina

Background: Recent studies indicate that there is selection bias for transmission of viral polymorphisms associated with higher viral fitness. Furthermore, after transmission and before a specific immune response is mounted in the recipient, the virus undergoes a number of reversions which allow an increase in their replicative capacity. These aspects, and others, affect the viral population characteristic of early acute infection. Methods: 160 single gag-gene amplifications were obtained by limiting-dilution RT-PCR from plasma samples of 8 ARV-naïve patients with early acute infection (