Cobertura vacinal e o movimento antivacina: o impacto na saúde pública no Brasil / Vaccination coverage and anti-vaccine movement: the impact on public health in Brazil / Cobertura de vacunación y movimiento antivacuna: el impacto en la salud pública en Brasil

A vacina constitui um dos principais métodos de prevenção contra doenças. Em 1973, o Brasil criou o Programa Nacional de Imunizações a fim de promover a imunização gratuita para a população, o que mais tarde tornou o país em referência mundial em vacinação. No entanto, a recusa vacinal ainda é um grande problema de saúde pública, sendo o movimento antivacina um dos destaques dessa realidade. Dessa forma, o objetivo deste artigo é avaliar como o movimento antivacina impacta na saúde pública no Brasil através da diminuição da cobertura vacinal. Trata-se de uma pesquisa de metodologia mista, com uma primeira etapa qualitativa, composta de uma revisão integrativa nas plataformas PubMed, LILACS e SciELO, no período de 2010 a 2020, e uma pesquisa documental em portais de movimentos antivacina; e uma segunda etapa quantitativa, em que foi realizado um estudo epidemiológico do tipo ecológico, com consulta nas bases eletrônicas do Datasus e no Sistema de Informações do Programa Nacional de Imunizações (SI-PNI), no período de 2010 a 2022. No período investigado, apenas em 2015 o Brasil alcançou a meta preconizada de cobertura vacinal, diferentemente dos anos seguintes, que apresentaram oscilações preocupantes. As publicações apresentam argumentos utilizados pelos grupos antivacina, evidenciados entre 2015 e 2019, período em que os dados de cobertura vacinal oscilaram. Assim, conclui-se que a ascensão do movimento antivacina é um dos fatores que influenciaram na queda da vacinação no Brasil, a exemplo do sarampo e da febre amarela.

The vaccine is one of the main methods of preventing diseases. Since 1973, Brazil created the National Immunization Program to ensure free immunization to the population, which later made the country a world reference in vaccination. However, vaccine refusal is still a great public health issue, and the anti-vaccine movement stand out in this reality. Thus, the purpose of this article is to evaluate how the anti-vaccine movement affects public health in Brazil with vaccination coverage reduction. This is a mixed methodology study, with first a qualitative step, composed of an integrative review in the platforms PubMed, LILACS, and SciELO, in the period from 2010 to 2020,and a documental research in portals of anti-vaccination movements; and a second quantitative step, where an epidemiological study of the ecological type was carried out, with consultation in the electronic databases of DATASUS and in the Information System of the National Immunization Program (SI-PNI) in the period of 2010 to 2022. In the investigative period, only in 2015 Brazil managed to reach the recommended vaccination coverage goal, unlike in the following years, which showed worrying fluctuations. The publications summarize arguments used by the anti-vaccination groups, evidenced between 2015 and 2019, a period in which the vaccination coverage data fluctuated. Therefore, it is clear that the rise of the anti-vaccination movement is a factor that influenced the drop in vaccination numbers in Brazil, with yellow fever and measles as examples.

La vacuna es uno de los principales métodos de prevención de enfermedades. En 1973, Brasil creó el Programa Nacional de Inmunización con el fin de promover la inmunización gratuita para la población, lo que luego convirtió al país en un referente mundial en vacunación. Sin embargo, la negativa de la vacuna sigue siendo un problema importante en la salud pública, y el movimiento antivacunas es uno de los aspectos más destacados de esta realidad. Así, el objetivo de este artículo es evaluar cómo el movimiento antivacunas impacta en la salud pública en Brasil mediante la disminución de la cobertura de vacunación. Se trata de un estudio epidemiológico mixto, con una primera etapa cualitativa, consistente en una revisión integradora en las plataformas PubMed, Lilacs y SciELO, en el período de 2010 a 2020, y una investigación documental en portales de movimientos antivacunas; y una segunda etapa cuantitativa, en la que se realizó un estudio epidemiológico de tipo ecológico, con consulta en las bases de datos electrónicas de DATASUS y en el Sistema de Información del Programa Nacional de Inmunización (SI-PNI), en el período de 2010 a 2022. Entre eses años, solo el año 2015 logró alcanzar la meta recomendada, a diferencia de los años siguientes, que mostraron fluctuaciones preocupantes en la cobertura de vacunación. Las publicaciones mostraron los argumentos utilizados por los grupos antivacina, evidenciados entre 2015 y 2019, período en que los datos de cobertura de la vacuna fluctuaron. Así, se concluye que la asunción del movimiento antivacunación es uno de los factores que influye en la caída de la vacunación en Brasil, como en el sarampión y la fiebre amarilla.

Digoxin is a potent inhibitor of Bunyamwera virus infection in cell culture.

Drug repurposing is a valuable source of new antivirals because many compounds used to treat a variety of pathologies can also inhibit viral infections. In this work, we have tested the antiviral capacity of four repurposed drugs to treat Bunyamwera virus (BUNV) infection in cell cultures. BUNV is the prototype of the Bunyavirales order, a large group of RNA viruses that includes important pathogens for humans, animals and plants. Mock- and BUNV-infected Vero and HEK293T cells were treated with non-toxic concentrations of digoxin, cyclosporin A, sunitinib and chloroquine. The four drugs inhibited BUNV infection with varying potency in Vero cells, and all except sunitinib also in HEK293T cells, with digoxin rendering the lowest half maximal inhibitory concentration (IC50). Since digoxin rendered the best results, we selected this drug for a more detailed study. Digoxin is an inhibitor of the Na+/K+ ATPase, a plasma membrane enzyme responsible for the energy-dependent exchange of cytoplasmic Na+ for extracellular K+ in mammalian cells and involved in many signalling pathways. Digoxin was shown to act at an early time point after viral entry reducing the expression of the viral proteins Gc and N. Effects on the cell cycle caused by BUNV and digoxin were also analysed. In Vero cells, digoxin favoured the transition from G1 phase of the cell cycle to S phase, an effect that might contribute to the anti-BUNV effect of digoxin in this cell type. Transmission electron microscopy showed that digoxin impedes the assembly of the characteristic spherules that harbour the BUNV replication complexes and the morphogenesis of new viral particles. Both BUNV and digoxin induce similar changes in the morphology of mitochondria that become more electron-dense and have swollen cristae. The alterations of this essential organelle might be one of the factors responsible for digoxin-induced inhibition of viral infection. Digoxin did not inhibit BUNV infection in BHK-21 cells that have a digoxin-resistant Na+/K+ ATPase, which suggests that the effects of the blockade of this enzyme is a key factor of the antiviral activity of digoxin in BUNV-infected Vero cells.

Impact of e-cigarettes as cancer risk: A protocol for systematic review and meta-analysis.

BACKGROUND: The use of electronic cigarettes is one of the current public health problems on increasing alert, has been growing at an accelerating rate, and has become a public health emergency. Its importance is explained by the continuous growth and acceleration of oncological rates among all ages versus the absence of high-quality evidence, correlated to the use of nicotine derived products, being at their regular versions or the new ones. Available preclinical data indicate that activation of the sympathetic nervous system by nicotine inhaled from e-cigarettes may stimulate cancer development and growth by several mechanisms, which results can significantly reduce life's quality. This systematic review and meta-analysis protocol aims to clarify the connection between the use of electronic cigarettes by adults over the age of 18 and the development of malignant neoplastic diseases. METHOD: The proposed systematic review and meta-analysis will be reported conforming to the preferred reporting items for systematic reviews and meta-analyses guidelines. Will include the following studies: case-control or cohort studies showing adults (18 years old age) using e-cigarettes. There will be no language or publication period restrictions. Articles published, but not peer-reviewed, will not be included in the review. Data will be entered in the Review Manager software (RevMan5.2.3). For dichotomous outcomes, we extracted or calculated the OR and 95% CI for each study. In case of heterogeneity (I²>50%), the random-effects model will be used to combine the studies to calculate the OR and 95% CI.

Modelos, sanciones y desarrollo de la finalidad educativa en el Sistema de Responsabilidad Penal para Adolescentes. Un análisis en el adolescente infractor del delito de hurto en la ciudad de Barranquilla / Models, sanctions and development of the educational purpose in the System of Criminal Responsibility for Adolescents. An analysis in the adolescent offender of the crime of theft in the city of Barranquilla / Modelos, sanções e desenvolvimento do propósito educacional no Sistema de Responsabilidade Criminal para Adolescentes. Uma análise do adolescente infrator do roubo na cidade de Barranquilla

La presente investigación jurídico-propositiva se ocupó de analizar el desarrollo de la finalidad educativa de las sanciones en el Sistema de Responsabilidad Penal para Adolescentes (SRPA), mediante la realización de entrevistas semiestructuradas a las autoridades administrativas y judiciales que imponen y vigilan las sanciones; en complemento con el análisis de los datos suministrados por los operadores del sistema sobre los adolescentes infractores de la Ley Penal, en particular de los autores del delito de hurto en la ciudad de Barranquilla (Colombia) durante el 2017 y 2018. Se encontró que 275 adolescentes ingresaron al SRPA por este delito punible; 211 cumplieron su medida no privativa de la libertad en el Centro Luz de Esperanza, donde desarrollan un proceso integrado por terapias individuales, grupales y familiares, simultáneo a los ciclos educativos, que al parecer son insuficientes para el logro de la finalidad educativa de la sanción, atendiendo los índices de reincidencia que se presentan. Se propuso un proceso educativo que desarrolle enfoques diferenciales, inclusivos y permanentes, que más allá de escolarizarlos los involucre en un proyecto de vida.

The present legal-propositional research was concerned with analyzing the development of the educational purpose of sanctions in the System of Criminal Responsibility for Adolescents (SRPA), by conducting semistructured interviews with administrative and judicial authorities who impose and monitor sanctions; in complement with the analysis of data provided by operators of the system on adolescent offenders of the Criminal Law, particularly perpetrators of the crime of theft in the city of Barranquilla (Colombia) during 2017 and 2018. It was found that 275 adolescents entered the SRPA for this punishable offense; 211 served their non-custodial measure in the Luz de Esperanza Center, where they develop a process integrated by individual, group and family therapies, simultaneous to the educational cycles, which apparently are insufficient for the achievement of the educational purpose of the sanction, attending to the recidivism rates that occur. It was proposed an educational process that develops differential, inclusive and permanent approaches, which, beyond schooling, involves them in a life project.

Esta pesquisa jurídico-propositiva preocupou-se em analisar o desenvolvimento do propósito educacional das sanções no Sistema de Responsabilidade Criminal para Adolescentes (SRPA), realizando entrevistas semi-estruturadas com autoridades administrativas e judiciais que impõem e monitoram sanções; além da análise dos dados fornecidos pelos operadores do sistema sobre adolescentes infratores do direito penal, em particular os autores do crime de furto na cidade de Barranquilla (Colômbia) durante 2017 e 2018. Foi constatado que 275 adolescentes entraram na SRPA por este delito punível; 211 serviram sua medida não-custodial no Centro Luz de Esperanza, onde desenvolvem um processo integrado por terapias individuais, grupais e familiares, simulta-neamente com os ciclos educativos, que aparentemente são insuficientes para o cumprimento do objetivo educativo da sanção, considerando as taxas de reincidência que ocorrem. Foi proposto um processo educacional que desenvolve abordagens diferenciadas, inclusivas e permanentes que vão além da escolaridade e as envolvem em um projeto de vida.

Drug repurposing for new, efficient, broad spectrum antivirals.

Emerging viruses are a major threat to human health. Recent outbreaks have emphasized the urgent need for new antiviral treatments. For several pathogenic viruses, considerable efforts have focused on vaccine development. However, during epidemics infected individuals need to be treated urgently. High-throughput screening of clinically tested compounds provides a rapid means to identify undiscovered, antiviral functions for well-characterized therapeutics. Repurposed drugs can bypass part of the early cost and time needed for validation and authorization. In this review we describe recent efforts to find broad spectrum antivirals through drug repurposing. We have chosen several candidates and propose strategies to understand their mechanism of action and to determine how resistance to antivirals develops in infected cells.

Comparison of Uncleaved and Mature Human Immunodeficiency Virus Membrane Envelope Glycoprotein Trimers.

The mature envelope glycoprotein (Env) spike on the surfaces of human immunodeficiency virus type 1 (HIV-1)-infected cells and virions is derived from proteolytic cleavage of a trimeric gp160 glycoprotein precursor. In these studies, we compared the conformations of cleaved and uncleaved membrane Envs with truncated cytoplasmic tails to those of stabilized soluble gp140 SOSIP.664 Env trimers. Deletion of the gp41 cytoplasmic tail did not significantly affect the sensitivity of viruses with the HIV-1AD8 Env to inhibition by antibodies or a CD4-mimetic compound. After glutaraldehyde fixation and purification from membranes, a cleaved Env exhibited a hydrodynamic radius of ∼10 nm and an antibody-binding profile largely consistent with that expected based on virus neutralization sensitivity. The purified cleaved Env trimers exhibited a hollow architecture with a central void near the trimer axis. Uncleaved Env, cross-linked and purified in parallel, exhibited a hydrodynamic radius similar to that of the cleaved Env. However, the uncleaved Env was recognized by poorly neutralizing antibodies and appeared by negative-stain electron microscopy to sample multiple conformations. Compared with membrane Envs, stabilized soluble gp140 SOSIP.664 Env trimers appear to be more compact, as reflected in their smaller hydrodynamic radii and negative-stain electron microscopy structures. The antigenic features of the soluble gp140 SOSIP.664 Env trimers differed from those of the cleaved membrane Env, particularly in gp120 V3 and some CD4-binding-site epitopes. Thus, proteolytic maturation allows the membrane-anchored Env to achieve a conformation that retains functional metastability but masks epitopes for poorly neutralizing antibodies.IMPORTANCE The entry of human immunodeficiency virus type 1 (HIV-1) into host cells is mediated by the envelope glycoprotein (Env) spike on the surface of the virus. Host antibodies elicited during natural HIV-1 infection or by vaccination can potentially recognize the Env spike and block HIV-1 infection. However, the changing shape of the HIV-1 Env spike protects the virus from antibody binding. Understanding the shapes of natural and man-made preparations of HIV-1 Envs will assist the development of effective vaccines against the virus. Here, we evaluate the effects of several Env modifications commonly used to produce Env preparations for vaccine studies and the determination of structure. We found that the cleavage of the HIV-1 Env precursor helps Env to assume its natural shape, which resists the binding of many commonly elicited antibodies. Stabilized soluble Envs exhibit more compact shapes but expose some Env elements differently than the natural Env.

Envelope glycoproteins sampling states 2/3 are susceptible to ADCC by sera from HIV-1-infected individuals.

Recent analysis of HIV-1 envelope glycoproteins (Env) dynamics showed that the unliganded Env trimer can potentially sample three conformations: a metastable "closed" conformation (State 1), an "open" CD4-bound conformation (State 3), and an intermediate "partially open" conformation (State 2). HIV-1 evolved several mechanisms to avoid "opening" its Env in order to evade immune responses such as antibody-dependent cellular cytotoxicity (ADCC), which preferentially targets Envs in the CD4-bound conformation on the surface of infected cells. Here we took advantage of a well-characterized single-residue change in the gp120 trimer association domain to modify Env conformation and evaluate its impact on ADCC responses. We found that cells infected with viruses expressing Env stabilized in States 2/3 become highly susceptible to ADCC responses by sera from HIV-1-infected individuals. Our results indicate that the conformations spontaneously sampled by the Env trimer at the surface of infected cells has a significant impact on ADCC responses.

Adaptation of HIV-1 to cells with low expression of the CCR5 coreceptor.

The binding of the human immunodeficiency virus (HIV-1) envelope glycoprotein (Env) trimer ((gp120/gp41)3) to the receptors CD4 and CCR5 triggers virus entry into host cells. To identify Env regions that respond to CCR5 binding, HIV-1 was serially passaged on a CD4-positive canine cell line expressing progressively lower levels of CCR5. HIV-1 replication was observed in cells expressing ~1300 CCR5 molecules/cell. Env changes that conferred this low-CCR5 replication phenotype were located outside of the known CCR5-binding region of the gp120 Env subunit and did not apparently increase CCR5 binding affinity. The adaptation-associated changes, located in the gp120 α1 helix and in the gp41 HR1 heptad repeat and membrane-proximal external region (MPER), enhanced HIV-1 replication in cells at all levels of CCR5 expression. The adapted Envs exhibited a greater propensity to undergo conformational changes, as evidenced by increased exposure of conserved regions near the CD4- and CCR5-binding sites.

Influence of the Envelope gp120 Phe 43 Cavity on HIV-1 Sensitivity to Antibody-Dependent Cell-Mediated Cytotoxicity Responses.

HIV-1-infected cells presenting envelope glycoproteins (Env) in the CD4-bound conformation on their surface are preferentially targeted by antibody-dependent cellular-mediated cytotoxicity (ADCC). HIV-1 has evolved sophisticated mechanisms to avoid the exposure of Env ADCC epitopes by downregulating CD4 and by limiting the overall amount of Env on the cell surface. In HIV-1, substitution of large residues such as histidine or tryptophan for serine 375 (S375H/W) in the gp120 Phe 43 cavity, where Phe 43 of CD4 contacts gp120, results in the spontaneous sampling of an Env conformation closer to the CD4-bound state. While residue S375 is well conserved in the majority of group M HIV-1 isolates, CRF01_AE strains have a naturally occurring histidine at this position (H375). Interestingly, CRF01_AE is the predominant circulating strain in Thailand, where the RV144 trial took place. In this trial, which resulted in a modest degree of protection, ADCC responses were identified as being part of the correlate of protection. Here we investigate the influence of the Phe 43 cavity on ADCC responses. Filling this cavity with a histidine or tryptophan residue in Env with a natural serine residue at this position (S375H/W) increased the susceptibility of HIV-1-infected cells to ADCC. Conversely, the replacement of His 375 by a serine residue (H375S) within HIV-1 CRF01_AE decreased the efficiency of the ADCC response. Our results raise the intriguing possibility that the presence of His 375 in the circulating strain where the RV144 trial was held contributed to the observed vaccine efficacy.IMPORTANCE HIV-1-infected cells presenting Env in the CD4-bound conformation on their surface are preferentially targeted by ADCC mediated by HIV-positive (HIV+) sera. Here we show that the gp120 Phe 43 cavity modulates the propensity of Env to sample this conformation and therefore affects the susceptibility of infected cells to ADCC. CRF01_AE HIV-1 strains have an unusual Phe 43 cavity-filling His 375 residue, which increases the propensity of Env to sample the CD4-bound conformation, thereby increasing susceptibility to ADCC.

Residues in the gp41 Ectodomain Regulate HIV-1 Envelope Glycoprotein Conformational Transitions Induced by gp120-Directed Inhibitors.

Interactions between the gp120 and gp41 subunits of the human immunodeficiency virus type 1 (HIV-1) envelope glycoprotein (Env) trimer maintain the metastable unliganded form of the viral spike. Binding of gp120 to the receptor, CD4, changes the Env conformation to promote gp120 interaction with the second receptor, CCR5 or CXCR4. CD4 binding also induces the transformation of Env into the prehairpin intermediate, in which the gp41 heptad repeat 1 (HR1) coiled coil is assembled at the trimer axis. In nature, HIV-1 Envs must balance the requirements to maintain the noncovalent association of gp120 with gp41 and to evade the host antibody response with the need to respond to CD4 binding. Here we show that the gp41 HR1 region contributes to gp120 association with the unliganded Env trimer. Changes in particular amino acid residues in the gp41 HR1 region decreased the efficiency with which Env moved from the unliganded state. Thus, these gp41 changes decreased the sensitivity of HIV-1 to cold inactivation and ligands that require Env conformational changes to bind efficiently. Conversely, these gp41 changes increased HIV-1 sensitivity to small-molecule entry inhibitors that block Env conformational changes induced by CD4. Changes in particular gp41 HR1 amino acid residues can apparently affect the relative stability of the unliganded state and CD4-induced conformations. Thus, the gp41 HR1 region contributes to the association with gp120 and regulates Env transitions from the unliganded state to downstream conformations.IMPORTANCE The development of an efficient vaccine able to prevent HIV infection is a worldwide priority. Knowledge of the envelope glycoprotein structure and the conformational changes that occur after receptor engagement will help researchers to develop an immunogen able to elicit antibodies that block HIV-1 transmission. Here we identify residues in the HIV-1 transmembrane envelope glycoprotein that stabilize the unliganded state by modulating the transitions from the unliganded state to the CD4-bound state.

Characterization of two distinct early post-entry blocks to HIV-1 in common marmoset lymphocytes.

In nature, primate lentiviruses infect humans and several Old World monkeys and apes. However, to date, lentiviruses infecting New World monkeys have not been described. We studied the susceptibility of common marmoset cells to HIV-1 infection and observed the presence of post-entry blocks to the early phase of HIV-1 infection in peripheral blood lymphocytes (PBLs) and a B lymphocytic cell line (B-LCL). The blocks present in these cells are dominant and phenotypically different from each other. In PBLs, the block occurs at the level of reverse transcription, reducing the accumulation of early and late transcripts, similar to the block imposed by TRIM5α. However, we have found that marmoset TRIM5α does not block HIV-1. In contrast, the restriction factor present in B-LCLs blocks HIV-1 replication at a later step, after nuclear entry, and inhibits integration. Additionally, we have identified an HIV-1 capsid mutant, N74D, that is able to escape the restriction in the marmoset B-LCLs. Our results suggest that the factors responsible for the blocks present in marmoset PBLs and B-LCLs are different. We propose the existence of at least two new restriction factors able to block HIV-1 infection in marmoset lymphocytes.

Co-receptor Binding Site Antibodies Enable CD4-Mimetics to Expose Conserved Anti-cluster A ADCC Epitopes on HIV-1 Envelope Glycoproteins.

Human immunodeficiency virus type 1 (HIV-1) has evolved a sophisticated strategy to conceal conserved epitopes of its envelope glycoproteins (Env) recognized by antibody-dependent cellular cytotoxicity (ADCC)-mediating antibodies. These antibodies, which are present in the sera of most HIV-1-infected individuals, preferentially recognize Env in its CD4-bound conformation. Accordingly, recent studies showed that small CD4-mimetics (CD4mc) able to "push" Env into this conformation sensitize HIV-1-infected cells to ADCC mediated by HIV+ sera. Here we test whether CD4mc also expose epitopes recognized by anti-cluster A monoclonal antibodies such as A32, thought to be responsible for the majority of ADCC activity present in HIV+ sera and linked to decreased HIV-1 transmission in the RV144 trial. We made the surprising observation that CD4mc are unable to enhance recognition of HIV-1-infected cells by this family of antibodies in the absence of antibodies such as 17b, which binds a highly conserved CD4-induced epitope overlapping the co-receptor binding site (CoRBS). Our results indicate that CD4mc initially open the trimeric Env enough to allow the binding of CoRBS antibodies but not anti-cluster A antibodies. CoRBS antibody binding further opens the trimeric Env, allowing anti-cluster A antibody interaction and sensitization of infected cells to ADCC. Therefore, ADCC responses mediated by cluster A antibodies in HIV-positive sera involve a sequential opening of the Env trimer on the surface of HIV-1-infected cells. The understanding of the conformational changes required to expose these vulnerable Env epitopes might be important in the design of new strategies aimed at fighting HIV-1.

A Highly Conserved gp120 Inner Domain Residue Modulates Env Conformation and Trimer Stability.

Previous studies have shown that highly conserved residues in the inner domain of gp120 are required for HIV-1 envelope glycoprotein (Env) transitions to the CD4-bound conformation (A. Finzi, S. H. Xiang, B. Pacheco, L. Wang, J. Haight, et al., Mol Cell 37:656-667, 2010, http://dx.doi.org/10.1016/j.molcel.2010.02.012; A. Desormeaux, M. Coutu, H. Medjahed, B. Pacheco, A. Herschhorn, et al., J Virol 87:2549-2562, 2013, http://dx.doi.org/10.1128/JVI.03104-12). Moreover, W69, a highly conserved residue located at the interface between layer 1 and layer 2 of the inner domain, was recently shown to be important for efficient Env recognition by CD4-induced (CD4i) antibodies capable of potent antibody-dependent cellular cytotoxicity (W. D. Tolbert, N. Gohain, M. Veillette, J. P. Chapleau, C. Orlandi, et al., 2016, Structure 24:697-709, http://dx.doi.org/10.1016/j.str.2016.03.005; S. Ding, M. Veillette, M. Coutu, J. Prevost, L. Scharf, et al., 2016, J Virol 90:2127-2134, http://dx.doi.org/10.1128/JVI.02779-15). We evaluated the contribution of the hydrophobicity of W69 to conformational changes of Env by replacing it with a series of residues with aliphatic or aromatic side chains of decreasing chain length. We have found that the hydrophobicity of residue 69 is important for Env processing, CD4 binding, and its transition to the CD4-bound conformation. The most deleterious effect was observed when W69 was replaced with alanine or glycine residues. However, the functions lost due to W69 mutations could be progressively restored with amino acids of increasing aliphatic chain length and fully recovered with residues bearing an aromatic ring. Interestingly, poor CD4 binding of W69A could be fully restored by introducing a compensatory mutation within layer 2 (S115W). Structural studies of HIV-1 gp120 coree W69A/S115W mutant bound to the CD4 peptide mimetic M48U1 and Fab of anti-cluster A antibody N60-i3 revealed no perturbations to the overall structure of the double mutant compared to the wild-type protein but identified higher mobility within the interface between layer 1 and layer 2, the bridging sheet region, and the CD4 binding site.IMPORTANCE HIV-1 Env transitions to the CD4-bound conformation are required for viral entry. Previous studies identified a highly conserved residue of the inner domain, W69, as being involved in these conformational transitions (A. Finzi, S. H. Xiang, B. Pacheco, L. Wang, J. Haight, et al., Mol Cell 37:656-667, 2010, http://dx.doi.org/10.1016/j.molcel.2010.02.012). Here, we show that W69, located at the interface between gp120 and gp41 in the PGT151-bound trimer, plays a critical role in the interprotomer signaling induced by CD4 binding. This new information might be useful in immunogen design.

HIV-1 Adapts To Replicate in Cells Expressing Common Marmoset APOBEC3G and BST2.

UNLABELLED: Previous studies have shown that a major block to HIV-1 replication in common marmosets operates at the level of viral entry and that this block can be overcome by adaptation of the virus in tissue-cultured cells. However, our current studies indicate that HIV-1 encounters additional postentry blocks in common marmoset peripheral blood mononuclear cells. Here, we show that the common marmoset APOBEC3G (A3G) and BST2 proteins block HIV-1 in cell cultures. Using a directed-evolution method that takes advantage of the natural ability of HIV-1 to mutate during replication, we have been able to overcome these blocks in tissue-cultured cells. In the adapted viruses, specific changes were observed in gag, vif, env, and nef. The contribution of these changes to virus replication in the presence of the A3G and BST2 restriction factors was studied. We found that certain amino acid changes in Vif and Env that arise during adaptation to marmoset A3G and BST2 allow the virus to replicate in the presence of these restriction factors. The changes in Vif reduce expression levels and encapsidation of marmoset APOBEC3G, while the changes in Env increase viral fitness and discretely favor cell-to-cell transmission of the virus, allowing viral escape from these restriction factors. IMPORTANCE: HIV-1 can infect only humans and chimpanzees. The main reason for this narrow tropism is the presence in many species of dominant-acting factors, known as restriction factors, that block viral replication in a species-specific way. We have been exploring the blocks to HIV-1 in common marmosets, with the ultimate goal of developing a new animal model of HIV-1 infection in these monkeys. In this study, we observed that common marmoset APOBEC3G and BST2, two known restriction factors, are able to block HIV-1 in cell cultures. We have adapted HIV-1 to replicate in the presence of these restriction factors and have characterized the mechanisms of escape. These studies can help in the development of a novel animal model for in vivo infection of marmosets with HIV-1-like viruses.

Determinar el nivel de satisfacción del usuario y de los profesionales en centros de atención primaria de salud

En el presente estudio se busca determinar el nivel de satisfacción de los profesionales y pacientes en centros de atención primaria de la salud. Se realizó el estudio entre 60 personas entre profesionales y pacientes, y lo relevante es que la mayoría de los pacientes están conformes con los servicios brindados en cuanto a la atención médica, la infraestructura, la solicitud de turnos, etc., desconociendo algunas cuestiones puntuales como la falta de insumos. En cambio desde el punto de vista de los profesionales se valoró negativamente la posibilidad de ascender en el puesto de trabajo, las condiciones de infraestructura y la falta de insumos.

In the following investigation it is searched to determine the level of satisfaction of professional and patients in the basic attention of health. This study was done among 60 people. They were professional and patients and it is very important to emphasize that the majority of the patients are satisfied with the service given. Not only with the medical attention, the place but also with the request of appointments, etc; and not paying attention to the lack of elements. On the other hand from the point of view of professionals the possibility of being promoted in their jobs, the conditions of the place and the lack of elements were not taken in count.

Nucleoside/nucleotide analog inhibitors of hepatitis B virus polymerase: mechanism of action and resistance.

Hepatitis B virus (HBV) polymerase and human immunodeficiency virus (HIV) reverse transcriptase are structurally related. However, the HBV enzyme has a protein priming activity absent in the HIV enzyme. Approved nucleoside/nucleotide inhibitors of the HBV polymerase include lamivudine, adefovir, telbivudine, entecavir and tenofovir. Although most of them target DNA elongation, guanosine and adenosine analogs (e.g. entecavir and tenofovir, respectively) also impair protein priming. Major mutational patterns conferring nucleoside/nucleotide analog resistance include the combinations rtL180M/rtM204(I/V) (for lamivudine, entecavir, telbivudine and clevudine) and rtA181V/rtN236T (for adefovir and tenofovir). However, development of drug resistance is very slow for entecavir and tenofovir. Novel nucleoside/nucleotide analogs in advanced clinical trials include phosphonates similar to adefovir or tenofovir, and new tenofovir derivatives with improved pharmacological properties.

Modeling virus- and antibody-specific factors to predict human immunodeficiency virus neutralization efficiency.

Efforts to prevent human immunodeficiency virus type 1 (HIV-1) infection would benefit from understanding the factors that govern virus neutralization by antibodies. We present a mechanistic model for HIV-1 neutralization that includes both virus and antibody parameters. Variations in epitope integrity on the viral envelope glycoprotein (Env) trimer and Env reactivity to bound antibody influence neutralization susceptibility. In addition, we define an antibody-specific parameter, the perturbation factor (PF), that describes the degree of conformational change in the Env trimer required for a given antibody to bind. Minimally perturbing (low-PF) antibodies can efficiently neutralize viruses with a broad range of Env reactivities due to fast on-rates and high affinity for Env. Highly perturbing (high-PF) antibodies inhibit only viruses with reactive (perturbation-sensitive) Envs, often through irreversible mechanisms. Accounting for these quantifiable viral and antibody-associated parameters helps to predict the observed profiles of HIV-1 neutralization by antibodies with a wide range of potencies.

Virus-specific effects of TRIM5α(rh) RING domain functions on restriction of retroviruses.

The tripartite motif protein TRIM5α restricts particular retrovirus infections by binding to the incoming capsid and inhibiting the early stage of virus infection. The TRIM5α RING domain exhibits E3 ubiquitin ligase activity and assists the higher-order association of TRIM5α dimers, which promotes capsid binding. We characterized a panel of RING domain mutants of the rhesus monkey TRIM5α (TRIM5α(rh)) protein. The RING domain function that significantly contributed to retroviral restriction depended upon the restricted virus. The E3 ubiquitin ligase activity of the RING domain contributes to the potency of HIV-1 restriction. Nonetheless, TRIM5α(rh) mutants without detectable E3 ubiquitin ligase activity still blocked reverse transcription and inhibited HIV-1 infection at a moderate level. When TRIM5α(rh) capsid binding was weakened by substitution with a less efficient B30.2/SPRY domain, the promotion of higher-order association by the RING domain was more important to HIV-1 restriction than its E3 ubiquitin ligase activity. For the restriction of N-tropic murine leukemia virus (N-MLV) and equine infectious anemia virus (EIAV) infection, promotion of higher-order association represented the major contribution of the RING domain. Thus, both identity of the target virus and the B30.2/SPRY domain-mediated affinity for the viral capsid determine the relative contribution of the two known RING domain functions to TRIM5α restriction of retrovirus infection.

Characterization of a dual-tropic human immunodeficiency virus (HIV-1) strain derived from the prototypical X4 isolate HXBc2.

Human immunodeficiency virus type 1 (HIV-1) coreceptor usage and tropism can be modulated by the V3 loop sequence of the gp120 exterior envelope glycoprotein. For coreceptors, R5 viruses use CCR5, X4 viruses use CXCR4, and dual-tropic (R5X4) viruses use either CCR5 or CXCR4. To understand the requirements for dual tropism, we derived and analyzed a dual-tropic variant of an X4 virus. Changes in the V3 base, which allow gp120 to interact with the tyrosine-sulfated CCR5 N-terminus, and deletion of residues 310/311 in the V3 tip were necessary for efficient CCR5 binding and utilization. Thus, both sets of V3 changes allowed CCR5 utilization with retention of the ability to use CXCR4. We also found that the stable association of gp120 with the trimeric envelope glycoprotein complex in R5X4 viruses, as in X4 viruses, is less sensitive to V3 loop changes than gp120-trimer association in R5 viruses.

The HIV-1 gp120 major variable regions modulate cold inactivation.

HIV-1 entry involves the viral envelope glycoproteins (Env gps) and receptors on the target cell. Receptor binding channels the intrinsic high potential energy of Env into the force required to fuse the membranes of virus and target cell. For some HIV-1 strains, prolonged incubation on ice decreases Env potential energy and results in functional inactivation. By characterizing chimeras between two primary clade C HIV-1 strains that differ in sensitivities to cold, soluble CD4, and neutralizing antibodies, we found that these properties were largely determined by discrete elements within the gp120 variable regions V1V2 and V3.