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1.
PLoS Pathog ; 19(11): e1011813, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38011306

RESUMO

Innate immune signaling in the central nervous system (CNS) exhibits many remarkable specializations that vary across cell types and CNS regions. In the setting of neuroinvasive flavivirus infection, neurons employ the immunologic kinase receptor-interacting kinase 3 (RIPK3) to promote an antiviral transcriptional program, independently of the traditional function of this enzyme in promoting necroptotic cell death. However, while recent work has established roles for neuronal RIPK3 signaling in controlling mosquito-borne flavivirus infections, including West Nile virus and Zika virus, functions for RIPK3 signaling in the CNS during tick-borne flavivirus infection have not yet been explored. Here, we use a model of Langat virus (LGTV) encephalitis to show that RIPK3 signaling is specifically required in neurons of the cerebellum to control LGTV replication and restrict disease pathogenesis. This effect did not require the necroptotic executioner molecule mixed lineage kinase domain like protein (MLKL), a finding similar to previous observations in models of mosquito-borne flavivirus infection. However, control of LGTV infection required a unique, region-specific dependence on RIPK3 to promote expression of key antiviral interferon-stimulated genes (ISG) in the cerebellum. This RIPK3-mediated potentiation of ISG expression was associated with robust cell-intrinsic restriction of LGTV replication in cerebellar granule cell neurons. These findings further illuminate the complex roles of RIPK3 signaling in the coordination of neuroimmune responses to viral infection, as well as provide new insight into the mechanisms of region-specific innate immune signaling in the CNS.


Assuntos
Vírus da Encefalite Transmitidos por Carrapatos , Encefalite Transmitida por Carrapatos , Doenças Transmitidas por Carrapatos , Carrapatos , Animais , Encéfalo/patologia , Vírus da Encefalite Transmitidos por Carrapatos/fisiologia , Encefalite Transmitida por Carrapatos/patologia , Interferons/metabolismo , Doenças Transmitidas por Carrapatos/patologia , Replicação Viral/genética , Camundongos
2.
BMC Pediatr ; 23(1): 28, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36653768

RESUMO

BACKGROUND: Childhood tuberculosis continues to be a major public health problem. Although the visibility of the epidemic in this population group has increased, further research is needed. OBJECTIVE: To design, implement and evaluate an integrated care strategy for children under five years old who are household contacts of bacteriologically confirmed pulmonary tuberculosis patients in Medellín and the Metropolitan Area. METHODS: A quasi-experimental study in which approximately 300 children who are household contacts of bacteriologically confirmed pulmonary tuberculosis patients from Medellín and the Metropolitan Area will be evaluated and recruited over one year. A subgroup of these children, estimated at 85, who require treatment for latent tuberculosis, will receive an integrated care strategy that includes: some modifications of the current standardized scheme in Colombia, with rifampicin treatment daily for four months, follow-up under the project scheme with nursing personnel, general practitioners, specialists, professionals from other disciplines such as social work, psychology, and nutritionist. Additionally, transportation and food assistance will be provided to encourage treatment compliance. This strategy will be compared with isoniazid treatment received by a cohort of children between 2015 and 2018 following the standardized scheme in the country. The study was approved by the CIB Research Ethics Committee and UPB. CLINICALTRIALS: gov identifier NCT04331262. DISCUSSION: This study is expected to contribute to the development of integrated care strategies for the treatment of latent tuberculosis in children. The results will have a direct impact on the management of childhood tuberculosis contributing to achieving the goals proposed by the World Health Organization's End TB Strategy. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT04331262 . Implementation of an Integrated Care Strategy for Children Contacts of Patients with Tuberculosis. Registered 2 April 2020.


Assuntos
Prestação Integrada de Cuidados de Saúde , Tuberculose Latente , Tuberculose Pulmonar , Tuberculose , Humanos , Criança , Pré-Escolar , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose Pulmonar/tratamento farmacológico , Isoniazida
3.
Int J Mol Sci ; 24(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37569656

RESUMO

NURR1 (Nuclear receptor-related 1 protein or NR4A2) is a nuclear protein receptor transcription factor with an essential role in the development, regulation, and maintenance of dopaminergic neurons and mediates the response to stressful stimuli during the perinatal period in mammalian brain development. The dysregulation of NURR1 activity may play a role in various diseases, including the onset and progression of neurodegenerative diseases, and several other pathologies. NURR1 is regulated by multiple mechanisms, among which phosphorylation by kinases or SUMOylation are the best characterized. Both post-translational modifications can regulate the activity of NURR1, affecting its stability and transcriptional activity. Other non-post-translational regulatory mechanisms include changes in its subcellular distribution or interaction with other protein partners by heterodimerization, also affecting its transcription activity. Here, we summarize the currently known regulatory mechanisms of NURR1 and provide a brief overview of its participation in pathological alterations.


Assuntos
Proteínas de Ligação a DNA , Fatores de Transcrição , Animais , Feminino , Gravidez , Proteínas de Transporte/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Mamíferos/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Humanos
4.
J Exp Zool B Mol Dev Evol ; 336(3): 300-314, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32419346

RESUMO

Development and evolution are dynamical processes under the continuous control of organismic and environmental factors. Generic physical processes, associated with biological materials and certain genes or molecules, provide a morphological template for the evolution and development of organism forms. Generic dynamical behaviors, associated with recurring network motifs, provide a temporal template for the regulation and coordination of biological processes. The role of generic physical processes and their associated molecules in development is the topic of the dynamical patterning module (DPM) framework. The role of generic dynamical behaviors in biological regulation is studied via the identification of the associated network motifs (NMs). We propose a joint DPM-NM perspective on the emergence and regulation of multicellularity focusing on a multicellular aggregative bacterium, Myxococcus xanthus. Understanding M. xanthus development as a dynamical process embedded in a physical substrate provides novel insights into the interaction between developmental regulatory networks and generic physical processes in the evolutionary transition to multicellularity.


Assuntos
Evolução Biológica , Myxococcus xanthus/crescimento & desenvolvimento , Padronização Corporal , Morfogênese
5.
Macromol Rapid Commun ; 42(11): e2100072, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33759273

RESUMO

A semi-crystalline, shape memory polymer (SMP) is fabricated by free radical cross-linking, polymerization, and grafting in a blend of n-octadecyl acrylate and polybutadiene (PB). Poly(n-octadecyl acrylate) (PODA) is a side-chain crystalline polymer, which serves as the structure-fixing network counterbalancing the elastically deformed, cross-linked polymer network. At a constant 50/50 ratio of monomer and polymer the amount of free radical initiator, dicumyl peroxide (DCP) is varied from 1% to 5% w/w PB. From swelling measurements and calculation of the cross-link density it is determined that DCP produces greater than one cross-link per DCP molecule. It is found that lower cross-linking efficiency is favorable for higher shape fixity. This lower efficiency is found to produce a higher degree of crystallinity of the PODA in the 2-5% DCP samples, which is determined to be the main driver of higher shape fixity of the polymer. A SMP with >90% fixity and 100% recovery at uniaxial strains from 34-79% is achieved. This material should be useful for mold processing of shape memory articles. This approach provides a method to decouple the elastomeric and thermoplastic portions of a SMP to convert commodity elastomers into SMPs and tailor the shape memory response.


Assuntos
Materiais Inteligentes , Acrilatos , Butadienos , Elastômeros , Radicais Livres , Polimerização
6.
Dev Growth Differ ; 60(2): 121-129, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29441522

RESUMO

Myxococcus xanthus is a myxobacterium that exhibits aggregation and cellular differentiation during the formation of fruiting bodies. Therefore, it has become a valuable model system to study the transition to multicellularity via cell aggregation. Although there is a vast set of experimental information for the development on M. xanthus, the dynamics behind cell-fate determination in this organism's development remain unclear. We integrate the currently available evidence in a mathematical network model that allows to test the set of molecular elements and regulatory interactions that are sufficient to account for the specification of the cell types that are observed in fruiting body formation. Besides providing a dynamic mechanism for cell-fate determination in the transition to multicellular aggregates of M. xanthus, this model enables the postulation of specific mechanisms behind some experimental observations for which no explanations have been provided, as well as new regulatory interactions that can be experimentally tested. Finally, this model constitutes a formal basis on which the continuously emerging data for this system can be integrated and interpreted.


Assuntos
Modelos Biológicos , Myxococcus xanthus/citologia , Myxococcus xanthus/crescimento & desenvolvimento , Movimento
7.
Am J Public Health ; 108(10): 1341-1344, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30138065

RESUMO

Although advances in treatment and diagnosis have transformed HIV into a chronic disease in high-income countries, a spectrum of structural, political, sociocultural, and health system barriers hamper early diagnosis and timely treatment of HIV in many middle- and low-income countries. In most Latin American countries, in spite of the great improvement in access to antiretroviral therapy, a large proportion of individuals infected with HIV do not know their status. In Colombia, the Joint United Nations Programme on HIV/AIDS currently estimates a much larger number of HIV cases than the number reported by Colombian authorities. Potential reasons for underdiagnosis and underreporting include sociocultural factors such as social stigma, restrictions in access to health care, a lack of public health research and robust surveillance systems, and the particular recent history and social situation related to the armed conflict the country has suffered through for several decades. Lessons from Colombia may be helpful in monitoring, understanding, and tackling the HIV epidemic in countries with long-term armed conflicts.


Assuntos
Conflitos Armados , Coleta de Dados/métodos , Infecções por HIV/epidemiologia , Disparidades em Assistência à Saúde , Adulto , Colômbia/epidemiologia , Países em Desenvolvimento , Feminino , Acessibilidade aos Serviços de Saúde , Humanos , Masculino , Vigilância da População , Estigma Social , Nações Unidas
8.
J Exp Zool B Mol Dev Evol ; 328(1-2): 165-178, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28217903

RESUMO

The transition to multicellularity, recognized as one the major transitions in evolution, has occurred independently several times. While multicellular development has been extensively studied in zygotic organisms including plant and animal groups, just a few aggregative multicellular organisms have been employed as model organisms for the study of multicellularity. Studying different evolutionary origins and modes of multicellularity enables comparative analyses that can help identifying lineage-specific aspects of multicellular evolution and generic factors and mechanisms involved in the transition to multicellularity. Among aggregative multicellular organisms, myxobacteria are a valuable system to explore the particularities that aggregation confers to the evolution of multicellularity and mechanisms shared with clonal organisms. Moreover, myxobacteria species develop fruiting bodies displaying a range of morphological diversity. In this review, we aim to synthesize diverse lines of evidence regarding myxobacteria development and discuss them in the context of Evo-Devo concepts and approaches. First, we briefly describe the developmental processes in myxobacteria, present an updated comparative analysis of the genes involved in their developmental processes and discuss these and other lines of evidence in terms of co-option and developmental system drift, two concepts key to Evo-Devo studies. Next, as has been suggested from Evo-Devo approaches, we discuss how broad comparative studies and integration of diverse genetic, physicochemical, and environmental factors into experimental and theoretical models can further our understanding of myxobacterial development, phenotypic variation, and evolution.


Assuntos
Evolução Biológica , Biologia do Desenvolvimento , Regulação Bacteriana da Expressão Gênica/fisiologia , Myxococcales/citologia , Myxococcales/genética
9.
J Biol Chem ; 288(8): 5506-17, 2013 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-23283970

RESUMO

Orphan receptor Nurr1 participates in the acquisition and maintenance of the dopaminergic cell phenotype, modulation of inflammation, and cytoprotection, but little is known about its regulation. In this study, we report that Nurr1 contains a bipartite nuclear localization signal (NLS) within its DNA binding domain and two leucine-rich nuclear export signals (NES) in its ligand binding domain. Together, these signals regulate Nurr1 shuttling in and out of the nucleus. Immunofluorescence and immunoblot analysis revealed that Nurr1 is mostly nuclear. A Nurr1 mutant lacking the NLS failed to enter the nucleus. The Nurr1 NLS sequence, when fused to green fluorescent protein, led to nuclear accumulation of this chimeric protein, indicating that this sequence was sufficient to direct nuclear localization of Nurr1. Furthermore, two NES were characterized in the ligand binding domain, whose deletion caused Nurr1 to accumulate predominantly in the nucleus. The Nurr1 NES was sensitive to CRM1 and could function as an independent export signal when fused to green fluorescent protein. Sodium arsenite, an agent that induces oxidative stress, promoted nuclear export of ectopically expressed Nurr1 in HEK293T cells, and the antioxidant N-acetylcysteine rescued from this effect. Similarly, in dopaminergic MN9D cells, arsenite induced the export of endogenous Nurr1, resulting in the loss of expression of Nurr1-dependent genes. This study illustrates that Nurr1 shuttling between the cytosol and nucleus is controlled by specific nuclear import and export signals and that oxidative stress can unbalance the distribution of Nurr1 to favor its cytosolic accumulation.


Assuntos
Transporte Ativo do Núcleo Celular , Regulação da Expressão Gênica , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , Sequência de Aminoácidos , Arsenitos/farmacologia , Transporte Biológico , Linhagem Celular Tumoral , Citosol/metabolismo , Humanos , Inflamação , Microscopia de Fluorescência/métodos , Modelos Biológicos , Modelos Genéticos , Dados de Sequência Molecular , Sinais de Localização Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Estresse Oxidativo , Doença de Parkinson/metabolismo , Fenótipo , Homologia de Sequência de Aminoácidos , Compostos de Sódio/farmacologia , Frações Subcelulares/metabolismo
10.
Front Public Health ; 12: 1321327, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38660359

RESUMO

Introduction: The control of the COVID-19 epidemic has been focused on the development of vaccines against SARS-CoV-2. All developed vaccines have reported safety and efficacy results in preventing infection and its consequences, although the quality of evidence varies depending on the vaccine considered. Different methodological designs have been used for their evaluation, which can influence our understanding of the effects of these interventions. CoronaVac is an inactivated vaccine, and it has been assessed in various studies, including clinical trials and observational studies. Given these differences, our objective was to explore the published information to answer the question: how has the efficacy/effectiveness and safety of CoronaVac been evaluated in different studies? This is to identify potential gaps and challenges to be addressed in understanding its effect. Methods: A scoping review was carried out following the methodology proposed by the Joanna Briggs Institute, which included studies carried out in humans as of 2020, corresponding to systematic reviews, clinical trials, analytical or descriptive observational studies, in which the effectiveness and/or safety of vaccines for COVID19 were evaluated or described. There were no age restrictions for the study participants. Results: The efficacy/effectiveness and safety of this vaccine was assessed through 113 studies. Nineteen corresponded to experimental studies, 7 of Phase II, 5 of Phase IV, and 4 were clinical trials with random assignment. Although some clinical trials with random assignment have been carried out, these have limitations in terms of feasibility, follow-up times, and with this, the possibility of evaluating safety outcomes that occur with low frequencies. Not all studies have used homogeneous methods of analysis. Both the prevention of infection, and the prevention of outcomes such as hospitalization or death, have been valued through similar outcomes, but some through multivariate analysis of dependencies, and others through analysis that try to infer causally through different control methods of confounding. Conclusion: Published information on the evaluation of the efficacy/effectiveness and safety of the CoronaVac is abundant. However, there are differences in terms of vaccine application schedules, population definition, outcomes evaluated, follow-up times, and safety assessment, as well as non-standardization in the reporting of results, which may hinder the generalizability of the findings. It is important to generate meetings and consensus strategies for the methods and reporting of this type of studies, which will allow to reduce the heterogeneity in their presentation and a better understanding of the effect of these vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Vacinas contra COVID-19/administração & dosagem , SARS-CoV-2 , Vacinação , Eficácia de Vacinas , Vacinas de Produtos Inativados
11.
Artigo em Inglês | MEDLINE | ID: mdl-38033309

RESUMO

The goal of the present article is to develop flexoelectric polyelectrolyte elastomers for energy harvesting based on a poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol) dimethacrylate (PEG-b-PPG-b-PEG-DMA) triblock grafted with an ionic liquid (IL) such as allylmethylimidazolium bis(trifluoromethane sulfonyl) imide (AMIMTFSI). The IL-grafted triblock copolymer network possesses a balance of reasonably good ionic conductivity and high ion polarization during cantilever bending. Of particular importance is the achievement of high flexoelectric coefficients in some flexoelectric polyelectrolyte elastomer (FPE) compositions reaching 1368 µC/m at ambient temperature during mechanical deformation under intermittent square-wave bending mode. With the addition of a 10 wt % lithium bis(trifluoromethane sulfonyl) imide (LiTFSI) salt, the flexoelectric coefficient further improved to 1737 µC/m, which is the highest among all piezoelectric and flexoelectric materials hitherto reported, and thus it opens a new opportunity for clean energy harvesting from a vibrating natural environment.

12.
bioRxiv ; 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-36747672

RESUMO

Innate immune signaling in the central nervous system (CNS) exhibits many remarkable specializations that vary across cell types and CNS regions. In the setting of neuroinvasive flavivirus infection, neurons employ the immunologic kinase receptor-interacting kinase 3 (RIPK3) to promote an antiviral transcriptional program, independently of the traditional function of this enzyme in promoting necroptotic cell death. However, while recent work has established roles for neuronal RIPK3 signaling in controlling mosquito-borne flavivirus infections, including West Nile virus and Zika virus, functions for RIPK3 signaling in the CNS during tick-borne flavivirus infection have not yet been explored. Here, we use a model of Langat virus (LGTV) encephalitis to show that RIPK3 signaling is specifically required in neurons of the cerebellum to control LGTV replication and restrict disease pathogenesis. This effect did not require the necroptotic executioner molecule mixed lineage kinase domain like protein (MLKL), a finding similar to previous observations in models of mosquito-borne flavivirus infection. However, control of LGTV infection required a unique, region-specific dependence on RIPK3 to promote expression of key antiviral interferon-stimulated genes (ISG) in the cerebellum. This RIPK3-mediated potentiation of ISG expression was associated with robust cell-intrinsic restriction of LGTV replication in cerebellar granule cell neurons. These findings further illuminate the complex roles of RIPK3 signaling in the coordination of neuroimmune responses to viral infection, as well as provide new insight into the mechanisms of region-specific innate immune signaling in the CNS.

13.
Microorganisms ; 11(4)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37110484

RESUMO

Research on the plant growth promoting microorganisms (PGPM) is increasing strongly due to the biotechnological potential for the agricultural, forestry, and food industry. The benefits of using PGPM in crop production are well proven; however, their incorporation in agricultural management is still limited. Therefore, we wanted to explore the gaps and challenges for the transfer of biotechnological innovations based on PGPM to the agricultural sector. Our systematic review of the state of the art of PGPM research and knowledge transfer takes Chile as an example. Several transfer limiting aspects are identified and discussed. Our two main conclusions are: neither academia nor industry can meet unfounded expectations during technology transfer, but mutually clarifying their needs, capabilities, and limitations is the starting point for successful collaborations; the generation of a collaborative innovation environment, where academia as well as public and private stakeholders (including the local community) take part, is crucial to enhance the acceptance and integration of PGPM on the way to sustainable agriculture.

14.
Travel Med Infect Dis ; 53: 102594, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37211342

RESUMO

INTRODUCTION: Colombia is the fifth most affected country by the global monkeypox outbreak and the second in LAC after Brazil. We describe the clinical and epidemiological characteristics of 521 patients with mpox in the country. METHODS: We conducted an observational analysis of laboratory-confirmed Mpox cases between June 29 and November 16, 2022. RESULTS: Most cases were young men living with HIV. The clinical evolution was primarily benign, with two deaths reported. We found some differences between women and men regarding their BMI, presence of lymphadenopathies, localization of lesions, and the antecedent of HIV infection. CONCLUSION: Although it seems that the epidemic curve for this outbreak of Mpox is decreasing not only in Colombia but globally, it could remain endemic. Therefore, it is necessary to maintain very close surveillance.


Assuntos
Infecções por HIV , Mpox , Masculino , Humanos , Feminino , Colômbia/epidemiologia , Infecções por HIV/epidemiologia , Brasil , Surtos de Doenças
15.
Int J STD AIDS ; 34(13): 921-931, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37429039

RESUMO

INTRODUCTION: Long-term use of antiretroviral therapy (ART) for HIV infection might lead to the necessity of switching regimens. We aimed to analyze the reasons for the ART switch, the time-to-switch of ART, and its associated factors in a Colombian cohort. METHODS: We conducted a retrospective cohort in 20 HIV clinics, including participants ≥18 years old with confirmed HIV infection who underwent an ART switch from January 2017 to December 2019 with at least 6 months of follow-up. A time-to-event analysis and an exploratory Cox model were performed. RESULTS: 796 participants switched ART during the study period. The leading cause of ART switch was drug intolerance (n = 449; 56.4%) with a median time-to-switch of 12.2 months. The longest median time-to-switch was due to regimen simplification (42.4 months). People ≥50 years old (HR = 0.6; 95% CI (0.5-0.7) and CDC stage 3 at diagnosis (HR = 0.8; 95% CI (0.6-0.9) had less hazard for switching ART over time. CONCLUSIONS: In this Colombian cohort, drug intolerance was the main cause of the ART switch, and the time-to-switch is shorter than reports from other countries. In Colombia, it is crucial to apply current recommendations for ART initiation to choose regimens with a better tolerability profile.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Humanos , Adolescente , Pré-Escolar , Infecções por HIV/tratamento farmacológico , Estudos Retrospectivos , Colômbia/epidemiologia , Antirretrovirais/efeitos adversos , Contagem de Linfócito CD4 , Carga Viral , Fármacos Anti-HIV/efeitos adversos
16.
Curr Opin Neurobiol ; 77: 102629, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36162201

RESUMO

Programmed cell death (PCD) is an essential mechanism of antimicrobial defense. Recent work has revealed an unexpected diversity in the types of PCD elicited during infection, as well as defined unique roles for different PCD modalities in shaping the immune response. Here, we review recent work describing unique ways in which PCD signaling operates within the infected central nervous system (CNS). These studies reveal striking complexity in the regulation of PCD signaling by CNS cells, including both protective and pathological outcomes in the control of infection. Studies defining the specialized molecular mechanisms shaping PCD responses in the CNS promise to yield much needed new insights into the pathogenesis of neuroinvasive viral infection, informing future therapeutic development.


Assuntos
Apoptose , Viroses , Humanos , Apoptose/fisiologia , Transdução de Sinais , Sistema Nervoso Central
17.
Microbiol Spectr ; 10(2): e0196221, 2022 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-35348350

RESUMO

Increasing the diagnostic capacity for COVID-19 (SARS-CoV-2 infection) is required to improve case detection, reduce COVID-19 expansion, and boost the world economy. Rapid antigen detection tests are less expensive and easier to implement, but their diagnostic performance has been questioned compared to reverse transcription-PCR (RT-PCR). Here, we evaluate the performance of the Standard Q COVID-19 antigen test for diagnosing SARS-CoV-2 infection and predicting contagiousness compared to RT-PCR and viral culture, respectively. The antigen test was 100.0% specific but only 40.9% sensitive for diagnosing infection compared to RT-PCR. Interestingly, SARS-CoV-2 contagiousness is highly unlikely with a negative antigen test since it exhibited a negative predictive value of 99.9% compared to viral culture. Furthermore, a cycle threshold (CT) value of 18.1 in RT-PCR was shown to be the one that best predicts contagiousness (area under the curve [AUC], 97.6%). Thus, screening people with antigen testing is a good approach to prevent SARS-CoV-2 contagion and allow returning to daily activities. IMPORTANCE The importance of our results is the excellent agreement between the Standard Q COVID-19 antigen test and the viral culture, indicating that it is important as a marker of contagiousness. Due to its high positive predictive value in situations of a high prevalence of infection, positive results do not require confirmation with another test. Likewise, its high negative predictive value for contagiousness makes possible to use this test as a criterion to discharge patients in isolation and screen people moving into environments that could facilitate the transmission of the virus. Screening people with antigen testing is a good approach to prevent SARS-CoV-2 contagion and allow returning to daily activities.


Assuntos
COVID-19 , Antígenos Virais/análise , COVID-19/diagnóstico , Teste Sorológico para COVID-19 , Humanos , SARS-CoV-2/genética , Sensibilidade e Especificidade
18.
Front Immunol ; 13: 793982, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35392101

RESUMO

CD8+ T-cells play a crucial role in the control of HIV replication. HIV-specific CD8+ T-cell responses rapidly expand since the acute phase of the infection, and it has been observed that HIV controllers harbor CD8+ T-cells with potent anti-HIV capacity. The development of CD8+ T-cell-based vaccine against HIV-1 has focused on searching for immunodominant epitopes. However, the strong immune pressure of CD8+ T-cells causes the selection of viral variants with mutations in immunodominant epitopes. Since HIV-1 mutations are selected under the context of a specific HLA-I, the circulation of viral variants with these mutations is highly predictable based on the most prevalent HLA-I within a population. We previously demonstrated the adaptation of circulating strains of HIV-1 to the HLA-A*02 molecule by identifying mutations under positive selection located in GC9 and SL9 epitopes derived from the Gag protein. Also, we used an in silico prediction approach and evaluated whether the mutations found had a higher or lower affinity to the HLA-A*02. Although this strategy allowed predicting the interaction between mutated peptides and HLA-I, the functional response of CD8+ T-cells that these peptides induce is unknown. In the present work, peripheral blood mononuclear cells from 12 HIV-1+ HLA-A*02:01+ individuals were stimulated with the mutated and wild-type peptides derived from the GC9 and SL9 epitopes. The functional profile of CD8+ T-cells was evaluated using flow cytometry, and the frequency of subpopulations was determined according to their number of functions and the polyfunctionality index. The results suggest that the quality of the response (polyfunctionality) could be associated with the binding affinity of the peptide to the HLA molecule, and the functional profile of specific CD8+ T-cells to mutated epitopes in individuals under cART is maintained.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Linfócitos T CD8-Positivos , Colômbia , Epitopos , Produtos do Gene gag , Antígenos HLA-A , Humanos , Epitopos Imunodominantes , Leucócitos Mononucleares , Peptídeos
19.
Int J STD AIDS ; 33(7): 641-651, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35502981

RESUMO

INTRODUCTION: HIV is an independent risk factor for cardiovascular diseases (CVD). There is insufficient information regarding comorbidities and cardiovascular risk factors in the Colombian HIV population. The aim of this study is to describe the prevalence of cardiovascular risk factors and comorbidities in patients from the HIV Colombian Group VIHCOL. METHODS: This is a multicenter, cross-sectional study conducted in the VIHCOL network in Colombia. Patients 18 years or older who had at least 6 months of follow-up were included. A stratified random sampling was performed to estimate the adjusted prevalence of cardiovascular risk factors and comorbidities. RESULTS: A total of 1616 patients were included. 83.2% were men, and the median age was 34 years. The adjusted prevalence for dyslipidemia, active tobacco use, hypothyroidism, and arterial hypertension was 51.2% (99% CI: 48.0%-54.4%), 7.6% (99% CI: 5.9%-9.3%), 7.4% (99% CI: 5.7%-9.1%), and 6.3% (99% CI: 4.8%-7.9%), respectively. CONCLUSIONS: In this Colombian HIV cohort, there is a high prevalence of modifiable CVD risk factors such as dyslipidemia and active smoking. Non-pharmacological and pharmacological measures for the prevention and management of these risk factors should be reinforced.


Assuntos
Doenças Cardiovasculares , Dislipidemias , Infecções por HIV , Adulto , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Colômbia/epidemiologia , Estudos Transversais , Dislipidemias/epidemiologia , Feminino , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Fatores de Risco de Doenças Cardíacas , Humanos , Masculino , Prevalência , Fatores de Risco
20.
Mol Neurobiol ; 58(12): 6697-6711, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34609698

RESUMO

In Parkinson's disease, the dysfunction of the dopaminergic nigrostriatal tract involves the loss of function of dopaminergic neurons of the substantia nigra pars compacta followed by death of these neurons. The functional recovery of these neurons requires a deep knowledge of the molecules that maintain the dopaminergic phenotype during adulthood and the mechanisms that subvert their activity. Previous studies have shown that transcription factor NURR1, involved in differentiation and maintenance of the dopaminergic phenotype, is downregulated by α-synuclein (α-SYN). In this study, we provide a mechanistic explanation to this finding by connecting α-SYN-induced activation of glycogen synthase kinase-3 (GSK-3) with NURR1 phosphorylation followed by proteasomal degradation. The use of sequential deletion mutants and single point mutants of NURR1 allowed the identification of a domain comprising amino acids 123-PSSPPTPSTPS-134 that is targeted by GSK-3 and leads to subsequent ubiquitination and proteasome degradation. This study provides a detailed analysis of the regulation of NURR1 stability by phosphorylation in synucleinopathies such as Parkinson's disease.


Assuntos
Neurônios Dopaminérgicos/efeitos dos fármacos , Quinase 3 da Glicogênio Sintase/metabolismo , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/metabolismo , alfa-Sinucleína/farmacologia , Linhagem Celular Tumoral , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Regulação para Baixo , Regulação da Expressão Gênica , Humanos , Fosforilação/efeitos dos fármacos
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