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1.
BMC Med Educ ; 23(1): 74, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36717846

RESUMEN

BACKGROUND: The continuous changes in the medical education to prepare medical doctors for the future requires updates in medical curriculum. However, the perspectives of the medical students are not frequently considered during the revision of the medical curriculum. In parallel with the process of defining and adjusting the medical curriculum, a large survey was performed to inquire the perspectives of the medical students at the Faculty of Medicine of the University of Porto (FMUP), Portugal, about the role of Histology and of Embryology. METHODS: Medical students at FMUP (Portugal) completed a structured and anonymous online questionnaire about the subjects Histology and Embryology. The questionnaire was prepared using questions of previous surveys performed in Europe, including another Portuguese medical school, and additional questions that were specifically prepared to this study. The questions referred to teaching methods, clinical relevance, use of virtual (digital) microscopes and association of Histology and Embryology with other subjects of the medical curriculum. RESULTS: Four hundred and sixty-two students participated in the study. The students in clinical years were more likely to recognise the clinical relevance of Histology (p = 0.016) and Embryology (p < 0.001). Students agree that teaching of these subjects would benefit from a clinical orientation (89% for Histology; 90% for Embryology). Students highlighted that Histology is crucial to understand Biopathology and agree (75%) that an integration of Histology with Biopathology could be considered in the medical curriculum. Most students (55%) agree that slide microscopes are more useful than virtual microscopes. CONCLUSIONS: Our study contributes to the debate about the evolution of medical curriculum. Gathering the medical students' perceptions using large surveys such as that performed in the present study may be useful to adapt the methods of teaching which may increase the motivation of the students. In the case of Histology and Embryology at the FMUP (Portugal) providing more clinically oriented teaching may be useful to motivate the students. Students of clinical years have strong clinical perspectives of Histology and Embryology and their enrolment in teaching of Histology and Embryology can also contribute to increase motivation of younger students. Consulting and involving medical students in the development of the medical curriculum can be positive and students should be more responsible and engaged in building their own education.


Asunto(s)
Educación de Pregrado en Medicina , Educación Médica , Histología , Estudiantes de Medicina , Humanos , Curriculum , Educación Médica/métodos , Escolaridad , Encuestas y Cuestionarios , Educación de Pregrado en Medicina/métodos , Histología/educación
2.
Conserv Biol ; 36(6): e13982, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35946319

RESUMEN

River conservation efforts traditionally focus on perennial watercourses (i.e., those that do not dry) and their associated aquatic biodiversity. However, most of the global river network is not perennial and thus supports both aquatic and terrestrial biodiversity. We assessed the conservation value of nonperennial rivers and streams (NPRS) in one of Europe's driest regions based on aquatic (macroinvertebrates, diatoms) and terrestrial (riparian plants, birds, and carabid beetles) community data. We mapped the distribution of taxa at 90 locations and across wide environmental gradients. Using the systematic planning tool Marxan, we identified priority conservation sites under 2 scenarios: aquatic taxa alone or aquatic and terrestrial taxa together. We explored how environmental factors (runoff, flow intermittence, elevation, salinity, anthropogenic impact) influenced Marxan's site selection frequency. The NPRS were selected more frequently (over 13% on average) than perennial rivers when both aquatic and terrestrial taxa were considered, suggesting that NPRS have a high conservation value at the catchment scale. We detected an underrepresentation of terrestrial taxa (8.4-10.6% terrestrial vs. 0.5-1.1% aquatic taxa were unrepresented in most Marxan solutions) when priority sites were identified based exclusively on aquatic biodiversity, which points to a low surrogacy value of aquatic taxa for terrestrial taxa. Runoff explained site selection when focusing on aquatic taxa (all best-fitting models included runoff, r2  = 0.26-0.27), whereas elevation, salinity, and flow intermittence were more important when considering both groups. In both cases, site selection frequency declined as anthropogenic impact increased. Our results highlight the need to integrate terrestrial and aquatic communities when identifying priority areas for conservation in catchments with NPRS. This is key to overcoming drawbacks of traditional assessments based only on aquatic taxa and to ensure the conservation of NPRS, especially as NPRS become more prevalent worldwide due to climate change and increasing water demands.


Los esfuerzos de conservación fluvial se enfocan tradicionalmente en los cauces permanentes (aquellos que no se secan) y la biodiversidad acuática asociada. Sin embargo, la mayor parte de la red hidrográfica mundial no es permanente, por lo que sustenta biodiversidad tanto acuática como terrestre. Evaluamos el valor de conservación de los ríos y arroyos no permanentes (RANP) en una de las regiones más secas de Europa con datos de comunidades acuáticas (macroinvertebrados, diatomeas) y terrestres (escarabajos carábidos). Mapeamos la distribución de los taxones en 90 localidades que cubren gradientes ambientales amplios. Con la herramienta de planificación sistemática Marxan identificamos los sitios prioritarios de conservación bajo dos escenarios: considerando sólo los taxones acuáticos o los taxones acuáticos y terrestres juntos. Exploramos cómo los factores ambientales (escorrentía, intermitencia del caudal, altitud, salinidad, impacto antropogénico) influyeron sobre la frecuencia de selección de sitio de Marxan. Los RANP fueron seleccionados con mayor frecuencia (más del 13% en promedio) que los ríos permanentes cuando consideramos los taxones acuáticos y terrestres, lo que sugiere que los RANP tienen un valor elevado de conservación a escala de cuenca. Detectamos que los taxones terrestres estaban infrarrepresentados (8.4-10.6% taxones terrestres vs. 0.5-1.1% acuáticos no tuvieron representación en la mayoría de las soluciones de Marxan) cuando los sitios prioritarios para la conservación se identificaban exclusivamente con la biodiversidad acuática, lo que indica que los taxones acuáticos tienen un reducido valor indicador para los taxones terrestres. La escorrentía determinó la selección de sitios cuando se basó en los taxones acuáticos (los mejores modelos incluyeron la escorrentía, r2 = 0.26-0.27), mientras que la altitud, la salinidad y la intermitencia del caudal fueron más importantes cuando se consideraron ambos grupos. En ambos casos, la frecuencia de selección disminuyó conforme se incrementó el impacto antropogénico. Nuestros resultados resaltan la necesidad de integrar las comunidades terrestres y acuáticas a la identificación de las áreas prioritarias para la conservación de la biodiversidad en cuencas con RANP. Lo anterior es importante para superar las evaluaciones tradicionales basadas solamente en los taxones acuáticos y para garantizar la conservación de los RANP, especialmente ahora que estos son cada vez más frecuentes a nivel mundial debido al cambio climático y a la creciente demanda de agua.


Asunto(s)
Ecosistema , Ríos , Conservación de los Recursos Naturales , Monitoreo del Ambiente/métodos , Biodiversidad
3.
Fish Physiol Biochem ; 48(2): 321-335, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-35146595

RESUMEN

This work aimed to evaluate the whole-organism and cellular level responses to different combinations of water temperature and salinity of the notothenioid Patagonotothen cornucola at the end of the yolk-sac larval stage. Egg masses of the species were collected in the wild and then maintained at natural water conditions (4 °C and 30 PSU). Newly hatched larvae were placed in aquaria with different combinations of water temperature (4 °C, 12 °C, and 16 °C) and salinity (15 and 30 PSU) during four days before yolk sac absorption. Larvae exposed to 12 °C grew more in length than those exposed to 16 °C, but yolk volume was more reduced in larvae exposed to 16 °C than those exposed to 4 °C and 30 PSU than of 15 PSU. In addition, a higher proportion of larvae exposed to 12 °C and 15 PSU completely absorbed their yolk. Whereas the more tolerant larvae to high temperatures were those exposed to 16 °C and 30 PSU, lipid peroxidation and protein oxidation were highest at natural and at 12 °C and 30 PSU conditions, respectively. The nutritional status (as standardized DNA/RNA index-sRD -) was low in all cases, even at natural conditions (average sRD ~ 1). Our study suggests that, in the context of climate change, the mortality rate of yolk-sac larvae of P. cornucola would not increase due to temperature or salinity stress. However, indirect effects (such as habitat degradation or changes in food availability) would be critical after complete absorption of the yolk.


Asunto(s)
Perciformes , Salinidad , Animales , Peces , Larva , Perciformes/fisiología , Temperatura , Agua , Saco Vitelino
4.
J Infect Dis ; 224(2): 258-268, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-33269401

RESUMEN

BACKGROUND: The human immunodeficiency virus (HIV)-1 latent reservoir (LR) in resting CD4+ T cells is a barrier to cure. LR measurements are commonly performed on blood samples and therefore may miss latently infected cells residing in tissues, including lymph nodes. METHODS: We determined the frequency of intact HIV-1 proviruses and proviral inducibility in matched peripheral blood (PB) and lymph node (LN) samples from 10 HIV-1-infected patients on antiretroviral therapy (ART) using the intact proviral DNA assay and a novel quantitative viral induction assay. Prominent viral sequences from induced viral RNA were characterized using a next-generation sequencing assay. RESULTS: The frequencies of CD4+ T cells with intact proviruses were not significantly different in PB versus LN (61/106 vs 104/106 CD4+ cells), and they were substantially lower than frequencies of CD4+ T cells with defective proviruses. The frequencies of CD4+ T cells induced to produce high levels of viral RNA were not significantly different in PB versus LN (4.3/106 vs 7.9/106), but they were 14-fold lower than the frequencies of cells with intact proviruses. Sequencing of HIV-1 RNA from induced proviruses revealed comparable sequences in paired PB and LN samples. CONCLUSIONS: These results further support the use of PB as an appropriate proxy for the HIV-1 LR in secondary lymphoid organs.


Asunto(s)
Infecciones por VIH , VIH-1 , Ganglios Linfáticos/virología , Provirus/aislamiento & purificación , Fármacos Anti-VIH/uso terapéutico , Linfocitos T CD4-Positivos , Infecciones por VIH/tratamiento farmacológico , VIH-1/aislamiento & purificación , Humanos , ARN Viral/aislamiento & purificación , Latencia del Virus
5.
J Infect Dis ; 221(5): 756-765, 2020 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-31581292

RESUMEN

BACKGROUND: Multiple factors influence the human immunodeficiency virus (HIV) antibody response produced during natural infection, leading to responses that can vary in specificity, strength, and breadth. METHODS: People who inject drugs identified as recently infected with HIV (n = 23) were analyzed for clustering of their viral sequences (genetic distance, <2%). Longitudinal antibody responses were identified for neutralizing antibody (Nab) potential, and differences in antibody subclass, specificity, and Fc receptor ligation using pseudovirus entry and multiplexed Fc array assays, respectively. Responses were analyzed for differences between subject groups, defined by similarity in the sequence of the infecting virus. RESULTS: Viral sequences from infected individuals were grouped into 3 distinct clusters with 7 unclustered individuals. Subjects in cluster 1 generally had lower antibody response magnitudes, except for antibodies targeting the V1/V2 region. Subjects in clusters 2 and 3 typically had higher antibody response magnitudes, with the Fv specificity of cluster 2 favoring gp140 recognition. NAb responses differed significantly between clusters for 3 of 18 pseudoviruses examined (P < .05), but there were no differences in overall NAb breadth (P = .62). DISCUSSION: These data demonstrate that individuals infected with similar viral strains can generate partially similar antibody responses, but these do not drastically differ from those in individuals infected with relatively unrelated strains.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida/complicaciones , Síndrome de Inmunodeficiencia Adquirida/epidemiología , Epidemias , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Abuso de Sustancias por Vía Intravenosa/complicaciones , Síndrome de Inmunodeficiencia Adquirida/inmunología , Síndrome de Inmunodeficiencia Adquirida/virología , Adulto , Anticuerpos Neutralizantes/inmunología , Baltimore/epidemiología , Secuencia de Bases/genética , Análisis por Conglomerados , Femenino , Estudios de Seguimiento , Proteína gp41 de Envoltorio del VIH/genética , VIH-1/genética , Humanos , Estudios Longitudinales , Masculino , Filogenia , Adulto Joven , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
6.
Clin Infect Dis ; 70(3): 501-508, 2020 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-30877752

RESUMEN

BACKGROUND: Elevated viral load (VL) early after antiretroviral therapy (ART) initiation appears frequently in pregnant and postpartum women living with human immunodeficiency virus; however the relative contributions of pre-ART drug resistance mutations (DRMs) vs nonadherence in the etiology of elevated VL are unknown. METHODS: Within a cohort of women initiating ART during pregnancy in Cape Town, South Africa, we compared women with elevated VL after initial suppression (cases, n = 80) incidence-density matched to women who maintained suppression over time (controls, n = 87). Groups were compared on pre-ART DRMs and detection of antiretrovirals in stored plasma. RESULTS: The prevalence of pre-ART DRMs was 10% in cases and 5% in controls (adjusted odds ratio [aOR], 1.53 [95% confidence interval {CI}, .4-5.9]); all mutations were to nonnucleoside reverse transcriptase inhibitors. At the time of elevated VL, 19% of cases had antiretrovirals detected in plasma, compared with 87% of controls who were suppressed at a matched time point (aOR, 131.43 [95% CI, 32.8-527.4]). Based on these findings, we estimate that <10% of all elevated VL in the cohort may be attributable to pre-ART DRMs vs >90% attributable to ART nonadherence. CONCLUSIONS: DRMs account for a small proportion of all elevated VL among women occurring in the 12 months after ART initiation during pregnancy in this setting, with nonadherence appearing to drive most episodes of elevated VL. Alongside the drive for access to more robust antiretroviral agents in resource-limited settings, there is an ongoing need for effective strategies to support ART adherence in this patient population.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Fármacos Anti-VIH/uso terapéutico , Antirretrovirales/uso terapéutico , Estudios de Casos y Controles , Resistencia a Medicamentos , Farmacorresistencia Viral/genética , Femenino , VIH , Infecciones por VIH/tratamiento farmacológico , Humanos , Mutación , Embarazo , Sudáfrica/epidemiología , Carga Viral
7.
Am J Med Genet A ; 182(11): 2533-2539, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32841469

RESUMEN

Jacobsen syndrome (MIM #147791) is a rare multisystem genomic disorder involving craniofacial abnormalities, intellectual disability, other neurodevelopmental defects, and terminal truncation of chromosome 11q, typically deleting ~170 to >340 genes. We describe the first case of Jacobsen syndrome caused by congenital chromoanasynthesis, an extreme form of complex chromosomal rearrangement. Six duplications and five deletions occurred on one copy of chromosome 11q with microhomology signatures in the breakpoint junctions, indicating an all-at-once replication-based rearrangement mechanism in a gametocyte or early post-zygotic cell. Eighteen genes were deleted from the Jacobsen region, including KIRREL3, which is associated with intellectual disability.


Asunto(s)
Anomalías Craneofaciales/genética , Discapacidad Intelectual/genética , Síndrome de Deleción Distal 11q de Jacobsen/genética , Proteínas Portadoras/genética , Niño , Aberraciones Cromosómicas , Cromosomas Humanos Par 11 , Eliminación de Gen , Duplicación de Gen , Humanos , Cariotipificación , Masculino , Proteínas de la Membrana/genética , Reacción en Cadena de la Polimerasa , Secuenciación Completa del Genoma
8.
Glob Chang Biol ; 25(5): 1612-1628, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30698905

RESUMEN

Understanding and predicting how biological communities respond to climate change is critical for assessing biodiversity vulnerability and guiding conservation efforts. Glacier- and snow-fed rivers are one of the most sensitive ecosystems to climate change, and can provide early warning of wider-scale changes. These rivers are frequently used for hydropower production but there is minimal understanding of how biological communities are influenced by climate change in a context of flow regulation. This study sheds light on this issue by disentangling structural (water temperature preference, taxonomic composition, alpha, beta and gamma diversities) and functional (functional traits, diversity, richness, evenness, dispersion and redundancy) effects of climate change in interaction with flow regulation in the Alps. For this, we compared environmental and aquatic invertebrate data collected in the 1970s and 2010s in regulated and unregulated alpine catchments. We hypothesized a replacement of cold-adapted species by warming-tolerant ones, high temporal and spatial turnover in taxa and trait composition, along with reduced taxonomic and functional diversities in consequence of climate change. We expected communities in regulated rivers to respond more drastically due to additive or synergistic effects between flow regulation and climate change. We found divergent structural but convergent functional responses between free-flowing and regulated catchments. Although cold-adapted taxa decreased in both of them, greater colonization and spread of thermophilic species was found in the free-flowing one, resulting in higher spatial and temporal turnover. Since the 1970s, taxonomic diversity increased in the free flowing but decreased in the regulated catchment due to biotic homogenization. Colonization by taxa with new functional strategies (i.e. multivoltine taxa with small body size, resistance forms, aerial dispersion and reproduction by clutches) increased functional diversity but decreased functional redundancy through time. These functional changes could jeopardize the ability of aquatic communities facing intensification of ongoing climate change or new anthropogenic disturbances.


Asunto(s)
Biota , Cambio Climático , Invertebrados/fisiología , Ríos , Movimientos del Agua , Animales , Biodiversidad , Ecosistema , Monitoreo del Ambiente , Invertebrados/clasificación , Invertebrados/crecimiento & desarrollo
9.
J Infect Dis ; 217(10): 1530-1534, 2018 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-29579256

RESUMEN

This report describes the identification of a genetically confirmed linked heterosexual human immunodeficiency virus (HIV) superinfection (HIV-SI) in a woman with chronic HIV infection who acquired a second strain of the virus from her husband. Serum neutralizing antibody (NAb) responses against their homologous and heterologous viruses, including the superinfecting strain, in the woman and her husband were examined before and after onset of HIV-SI. The woman displayed a moderately potent and broad anti-HIV NAb response prior to superinfection but did not possess NAb activity against the superinfecting strain. This case highlights the unique potential of linked HIV-SI studies to examine natural protection from HIV infection.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Formación de Anticuerpos/inmunología , Anticuerpos Anti-VIH/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Sobreinfección/inmunología , Anticuerpos Neutralizantes/genética , Formación de Anticuerpos/genética , Femenino , Anticuerpos Anti-VIH/genética , Infecciones por VIH/genética , Heterosexualidad/fisiología , Humanos , Masculino , Pruebas de Neutralización/métodos , Sobreinfección/genética , Sobreinfección/virología
10.
Retrovirology ; 15(1): 47, 2018 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-29976219

RESUMEN

BACKGROUND: The ability of HIV-1 to integrate into the genomes of quiescent host immune cells, establishing a long-lived latent viral reservoir (LVR), is the primary obstacle to curing these infections. Quantitative viral outgrowth assays (QVOAs) are the gold standard for estimating the size of the replication-competent HIV-1 LVR, measured by the number of infectious units per million (IUPM) cells. QVOAs are time-consuming because they rely on culturing replicate wells to amplify the production of virus antigen or nucleic acid to reproducibly detectable levels. Sequence analysis can reduce the required number of culture wells because the virus genetic diversity within the LVR provides an internal replication and dilution series. Here we develop a Bayesian method to jointly estimate the IUPM and variant frequencies (a measure of clonality) from the sequence diversity of QVOAs. RESULTS: Using simulation experiments, we find our Bayesian approach confers significantly greater accuracy over current methods to estimate the IUPM, particularly for reduced numbers of QVOA replicates and/or increasing actual IUPM. Furthermore, we determine that the improvement in accuracy is greater with increasing genetic diversity in the sample population. We contrast results of these different methods applied to new HIV-1 sequence data derived from QVOAs from two individuals with suppressed viral loads from the Rakai Health Sciences Program in Uganda. CONCLUSIONS: Utilizing sequence variation has the additional benefit of providing information on the contribution of clonality of the LVR, where high clonality (the predominance of a single genetic variant) suggests a role for cell division in the long-term persistence of the reservoir. In addition, our Bayesian approach can be adapted to other limiting dilution assays where positive outcomes can be partitioned by their genetic heterogeneity, such as immune cell populations and other viruses.


Asunto(s)
Variación Genética , Genoma Viral , Infecciones por VIH/virología , VIH-1/fisiología , Carga Viral , Latencia del Virus , Teorema de Bayes , Linfocitos T CD4-Positivos/virología , Simulación por Computador , Reservorios de Enfermedades , Humanos , Activación Viral , Replicación Viral
11.
Proc Natl Acad Sci U S A ; 112(35): 10908-13, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26286988

RESUMEN

Poxviruses reproduce in the host cytoplasm and encode most or all of the enzymes and factors needed for expression and synthesis of their double-stranded DNA genomes. Nevertheless, the mode of poxvirus DNA replication and the nature and location of the replication origins remain unknown. A current but unsubstantiated model posits only leading strand synthesis starting at a nick near one covalently closed end of the genome and continuing around the other end to generate a concatemer that is subsequently resolved into unit genomes. The existence of specific origins has been questioned because any plasmid can replicate in cells infected by vaccinia virus (VACV), the prototype poxvirus. We applied directional deep sequencing of short single-stranded DNA fragments enriched for RNA-primed nascent strands isolated from the cytoplasm of VACV-infected cells to pinpoint replication origins. The origins were identified as the switching points of the fragment directions, which correspond to the transition from continuous to discontinuous DNA synthesis. Origins containing a prominent initiation point mapped to a sequence within the hairpin loop at one end of the VACV genome and to the same sequence within the concatemeric junction of replication intermediates. These findings support a model for poxvirus genome replication that involves leading and lagging strand synthesis and is consistent with the requirements for primase and ligase activities as well as earlier electron microscopic and biochemical studies implicating a replication origin at the end of the VACV genome.


Asunto(s)
Replicación del ADN , ADN Viral/biosíntesis , Secuenciación de Nucleótidos de Alto Rendimiento , Nucleótidos/genética , Virus Vaccinia/genética
12.
J Virol ; 90(9): 4469-4480, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26889040

RESUMEN

UNLABELLED: Molluscum contagiosum virus (MOCV), the only circulating human-specific poxvirus, has a worldwide distribution and causes benign skin lesions that may persist for months in young children and severe infections in immunosuppressed adults. Studies of MOCV are restricted by the lack of an efficient animal model or a cell culture replication system. We used next-generation sequencing to analyze and compare polyadenylated RNAs from abortive MOCV infections of several cell lines and a human skin lesion. Viral RNAs were detected for 14 days after MOCV infection of cultured cells; however, there was little change in the RNA species during this time and a similar pattern occurred in the presence of an inhibitor of protein synthesis, indicating a block preventing postreplicative gene expression. Moreover, a considerable number of MOCV RNAs mapped to homologs of orthopoxvirus early genes, but few did so to homologs of intermediate or late genes. The RNAs made during in vitro infections represent a subset of RNAs detected in human skin lesions which mapped to homologs of numerous postreplicative as well as early orthopoxvirus genes. Transfection experiments using fluorescent protein and luciferase reporters demonstrated that vaccinia virus recognized MOCV intermediate and late promoters, indicating similar gene regulation. The specific recognition of the intermediate promoter in MOCV-infected cells provided evidence for the synthesis of intermediate transcription factors, which are products of early genes, but not for late transcription factors. Transcriptome sequencing (RNA-seq) and reporter gene assays may be useful for testing engineered cell lines and conditions that ultimately could provide an in vitro replication system. IMPORTANCE: The inability to propagate molluscum contagiosum virus, which causes benign skin lesions in young children and more extensive infections in immunosuppressed adults, has constrained our understanding of the biology of this human-specific virus. In the present study, we characterized the RNAs synthesized in abortively infected cultured cells and a human skin lesion by next-generation sequencing. These studies provided an initial transcription map of the MOCV genome, suggested temporal regulation of gene expression, and indicated that the in vitro replication block occurs prior to intermediate and late gene expression. RNA-seq and reporter assays, as described here, may help to further evaluate MOCV gene expression and define conditions that could enable MOCV replication in vitro.


Asunto(s)
Regulación Viral de la Expresión Génica , Molusco Contagioso/patología , Molusco Contagioso/virología , Virus del Molusco Contagioso/genética , Transcriptoma , Línea Celular , Células Cultivadas , Biología Computacional/métodos , Secuencia de Consenso , Perfilación de la Expresión Génica , Orden Génico , Genes Virales , Genoma Viral , Humanos , Anotación de Secuencia Molecular , Virus del Molusco Contagioso/ultraestructura , Regiones Promotoras Genéticas , ARN Viral , Análisis de Secuencia de ADN
13.
Proc Natl Acad Sci U S A ; 110(20): E1849-56, 2013 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-23630283

RESUMEN

Screening a complete mouse phosphatase lentiviral shRNA library using high-throughput sequencing revealed several phosphatases that regulate CD4 T-cell differentiation. We concentrated on two lipid phosphatases, the myotubularin-related protein (MTMR)9 and -7. Silencing MTMR9 by shRNA or siRNA resulted in enhanced T-helper (Th)1 differentiation and increased Th1 protein kinase B (PKB)/AKT phosphorylation while silencing MTMR7 caused increased Th2 and Th17 differentiation and increased AKT phosphorylation in these cells. Irradiated mice reconstituted with MTMR9 shRNA-transduced bone marrow cells had an elevated proportion of T-box transcription factor T-bet expressors among their CD4 T cells. After adoptive transfer of naïve cells from such reconstituted mice, immunization resulted in a greater proportion of T-box transcription factor T-bet-expressing cells. Thus, myotubularin-related proteins have a role in controlling in vitro and in vivo Th-cell differentiation, possibly through regulation of phosphatidylinositol [3,4,5]-trisphosphate activity.


Asunto(s)
Proteínas Tirosina Fosfatasas no Receptoras/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Linfocitos T/citología , Animales , Diferenciación Celular , Perfilación de la Expresión Génica , Biblioteca de Genes , Silenciador del Gen , Células HEK293 , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Fosfohidrolasa PTEN/metabolismo , Fosforilación , ARN Interferente Pequeño/metabolismo , Células Th17/citología , Células Th2/citología
14.
J Clin Microbiol ; 52(3): 844-8, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24371237

RESUMEN

HIV-1 superinfection (SI) occurs when an infected individual acquires a distinct new viral strain. The rate of superinfection may be reflective of the underlying HIV risk in a population. The Centre for the AIDS Programme of Research in South Africa (CAPRISA) 004 clinical trial demonstrated that women who used a tenofovir-containing microbicide gel had lower rates of HIV infection than women using a placebo gel. Women who contracted HIV-1 during the trial were screened for the occurrence of superinfection by next-generation sequencing of the viral gag and env genes. There were two cases (one in each trial arm) of subtype C superinfection identified from the 76 women with primary infection screened at two time points (rate of superinfection, 1.5/100 person-years). Both women experienced a >0.5-log increase in viral load during the window when superinfection occurred. The rate of superinfection was significantly lower than the overall primary HIV incidence in the microbicide trial (incidence rate ratio [IRR], 0.20; P=0.003). The women who seroconverted during the trial reported a significant increase in sexual contact with their stable partner 4 months after seroconversion (P<0.001), which may have lowered the risk of superinfection in this population. The lower frequency of SI compared to the primary incidence is in contrast to a report from a general heterosexual African population but agrees with a study of high-risk women in Kenya. A better understanding of the rate of HIV superinfection could have important implications for ongoing HIV vaccine research.


Asunto(s)
Antiinfecciosos/uso terapéutico , Infecciones por VIH/prevención & control , Infecciones por VIH/transmisión , VIH-1/aislamiento & purificación , Sobreinfección/diagnóstico , Cremas, Espumas y Geles Vaginales/uso terapéutico , Adenina/análogos & derivados , Adenina/uso terapéutico , Adulto , Quimioprevención/métodos , Femenino , Infecciones por VIH/epidemiología , VIH-1/clasificación , VIH-1/genética , Humanos , Incidencia , Kenia , Organofosfonatos/uso terapéutico , Análisis de Secuencia de ADN , Sudáfrica , Sobreinfección/epidemiología , Tenofovir , Carga Viral , Adulto Joven , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Productos del Gen gag del Virus de la Inmunodeficiencia Humana/genética
15.
Metab Brain Dis ; 29(2): 261-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24515303

RESUMEN

HIV-associated neurocognitive disorders (HAND) are a common neurological manifestation of HIV infection. A previous study suggested that HIV dementia may be more common among patients with subtype D virus than among those with subtype A virus among HIV+ individuals with advanced immunosuppression. We conducted a study to evaluate the frequency of HIV dementia, and the association of HIV dementia with HIV subtype and compartmentalization among HIV+ individuals with moderate and advanced immunosuppression (CD4 lymphocyte count >150 cells/µL and <250 cells/µL). The study enrolled 117 antiretroviral naïve HIV+ individuals in Kampala, Uganda. HIV+ individuals received neurological, neuropsychological testing, and functional assessments, and gag and gp41 regions were subtyped. Subjects were considered infected with a specific subtype if both regions analyzed were from the same subtype. 41% of the HIV+ individuals had HIV dementia (mean CD4 lymphocyte count = 233 cells/µL). 67 individuals had subtype A, 25 individuals had subtype D, 24 individuals were classified as A/D recombinants, and one individual had subtype C. There was no difference in the frequency of HIV dementia when stratified by HIV subtype A and D and no association with compartmentalization between the cerebrospinal fluid and peripheral blood. These results suggest that HIV dementia is common in HIV+ individuals in Uganda. There was no association between HIV subtype and dementia among HIV+ individuals with moderate and advanced immunosuppression. Future studies should be performed to confirm these results.


Asunto(s)
Complejo SIDA Demencia/diagnóstico , Complejo SIDA Demencia/genética , Progresión de la Enfermedad , VIH-1/genética , Tolerancia Inmunológica/genética , Complejo SIDA Demencia/epidemiología , Adulto , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/genética , VIH-1/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Encuestas y Cuestionarios , Uganda/epidemiología , Adulto Joven
16.
Healthcare (Basel) ; 12(5)2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38470666

RESUMEN

Neuropathic pain is caused by a lesion or disease of the somatosensory system and is one of the most incapacitating pain types, representing a significant non-met medical need. Due to the increase in research in the field and since innovative therapeutic strategies are required, namely in intractable neuropathic pain, neurostimulation has been used. Within this approach, transcranial magnetic stimulation (TMS) that uses a transient magnetic field to produce electrical currents over the cortex emerges as a popular method in the literature. Since this is an area in expansion and due to the putative role of TMS, we performed a bibliometric analysis in Scopus with the primary objective of identifying the scientific production related to the use of TMS to manage neuropathic pain. The research had no restrictions, and the analysis focused on the characteristics of the literature retrieved, scientific collaboration and main research topics from inception to 6 July 2023. A total of 474 articles were collected. A biggest co-occurrence between the terms "neuropathic pain" and "transcranial magnetic stimulation" was obtained. The journal "Clinical Neurophysiology" leads the Top 5 most productive sources. The United States is the most productive country, with 50% of US documents being "review articles", followed by France, with 56% of French documents being "original articles". Lefaucheur, JP and Saitoh, Y are the two most influential authors. The most frequent type of document was "original article". Most of the studies (34%) that identified the neuropathic pain type focused on traumatic neuropathic pain, although a large proportion (38%) did not report the neuropathic pain type. This study allows us to provide a general overview of the field of TMS application for neuropathic pain and is useful for establishing future directions of research in this field.

17.
Vector Borne Zoonotic Dis ; 24(5): 278-284, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38252532

RESUMEN

Background: The taxonomic status of the relapsing fever spirochete Borrelia hermsii in western North America was established in 1942 and based solely on its specific association with the soft tick vector Ornithodoros hermsi. Multilocus sequence typing (MLST) of the 16S rRNA, flaB, gyrB, glpQ, and 16S-23S rRNA intergenic spacer of B. hermsii isolates collected over many years from various geographic locations and biological sources identified two distinct clades designated previously as B. hermsii Genomic Group I (GGI) and Genomic Group II (GGII). To better assess the taxonomic relationship of these two genomic groups to each other and other species of Borrelia, DNA sequences of the entire linear chromosome were determined. Materials and Methods: Genomic DNA samples were prepared from 11 spirochete isolates grown in Barbour-Stoenner-Kelly-H medium. From these preparations, DNA sequences of the entire linear chromosome of two isolates of B. hermsii belonging to each genomic group and seven additional species were determined. Results: Chromosomal sequences of four isolates of B. hermsii contained 919,212 to 922,307 base pairs. DNA sequence identities between the two genomic groups of B. hermsii were 95.86-95.99%, which were more divergent than chromosomal sequences comparing Borrelia parkeri and Borrelia turicatae (97.13%), Borrelia recurrentis and Borrelia duttonii (97.07%), and Borrelia crocidurae and B. duttonii (97.09%). The 3' end of the chromosome of the two GGII isolates also contained a unique intact oppA gene absent from all other species examined. Conclusion: Previous MLST and the chromosomal sequences presented herein support the division of the B. hermsii species complex into two species, B. hermsii sensu stricto ( = GGI) and Borrelia nietonii sp. nov. ( = GGII). We name this unique relapsing fever spirochete in honor of our late friend and colleague Dr. Nathan Nieto for his outstanding contributions to our understanding of tick-borne relapsing fever.


Asunto(s)
Borrelia , Ornithodoros , Filogenia , Fiebre Recurrente , Borrelia/genética , Borrelia/aislamiento & purificación , Borrelia/clasificación , Ornithodoros/microbiología , Animales , Fiebre Recurrente/microbiología , ADN Bacteriano/genética , Tipificación de Secuencias Multilocus , ARN Ribosómico 16S/genética , Genoma Bacteriano
18.
Pharmaceutics ; 16(6)2024 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-38931902

RESUMEN

Glioblastoma multiform (GBM) is considered the deadliest brain cancer. Conventional therapies are followed by poor patient survival outcomes, so novel and more efficacious therapeutic strategies are imperative to tackle this scourge. Gene therapy has emerged as an exciting and innovative tool in cancer therapy. Its combination with chemotherapy has significantly improved therapeutic outcomes. In line with this, our team has developed temozolomide-transferrin (Tf) peptide (WRAP5)/p53 gene nanometric complexes that were revealed to be biocompatible with non-cancerous cells and in a zebrafish model and were able to efficiently target and internalize into SNB19 and U373 glioma cell lines. The transfection of these cells, mediated by the formulated peptide-drug/gene complexes, resulted in p53 expression. The combined action of the anticancer drug with p53 supplementation in cancer cells enhances cytotoxicity, which was correlated to apoptosis activation through quantification of caspase-3 activity. In addition, increased caspase-9 levels revealed that the intrinsic or mitochondrial pathway of apoptosis was implicated. This assumption was further evidenced by the presence, in glioma cells, of Bax protein overexpression-a core regulator of this apoptotic pathway. Our findings demonstrated the great potential of peptide TMZ/p53 co-delivery complexes for cellular transfection, p53 expression, and apoptosis induction, holding promising therapeutic value toward glioblastoma.

19.
EBioMedicine ; 102: 105040, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38485563

RESUMEN

BACKGROUND: The principal barrier to an HIV cure is the presence of the latent viral reservoir (LVR), which has been understudied in African populations. From 2018 to 2019, Uganda instituted a nationwide rollout of ART consisting of Dolutegravir (DTG) with two NRTI, which replaced the previous regimen of one NNRTI and the same two NRTI. METHODS: Changes in the inducible replication-competent LVR (RC-LVR) of ART-suppressed Ugandans with HIV (n = 88) from 2015 to 2020 were examined using the quantitative viral outgrowth assay. Outgrowth viruses were examined for viral evolution. Changes in the RC-LVR were analyzed using three versions of a Bayesian model that estimated the decay rate over time as a single, linear rate (model A), or allowing for a change at time of DTG initiation (model B&C). FINDINGS: Model A estimated the slope of RC-LVR change as a non-significant positive increase, which was due to a temporary spike in the RC-LVR that occurred 0-12 months post-DTG initiation (p < 0.005). This was confirmed with models B and C; for instance, model B estimated a significant decay pre-DTG initiation with a half-life of 6.9 years, and an ∼1.7-fold increase in the size of the RC-LVR post-DTG initiation. There was no evidence of viral failure or consistent evolution in the cohort. INTERPRETATION: These data suggest that the change from NNRTI- to DTG-based ART is associated with a significant temporary increase in the circulating RC-LVR. FUNDING: Supported by the NIH (grant 1-UM1AI164565); Gilead HIV Cure Grants Program (90072171); Canadian Institutes of Health Research (PJT-155990); and Ontario Genomics-Canadian Statistical Sciences Institute.


Asunto(s)
Pueblo de África Oriental , Infecciones por VIH , Inhibidores de Integrasa VIH , VIH-1 , Humanos , Antirretrovirales/uso terapéutico , Teorema de Bayes , Linfocitos T CD4-Positivos , Infecciones por VIH/tratamiento farmacológico , Inhibidores de Integrasa VIH/farmacología , Inhibidores de Integrasa VIH/uso terapéutico , Carga Viral , Latencia del Virus
20.
J Biol Chem ; 287(37): 31050-60, 2012 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-22829601

RESUMEN

Poxviruses are large DNA viruses that replicate within the cytoplasm and encode a complete transcription system, including a multisubunit RNA polymerase, stage-specific transcription factors, capping and methylating enzymes, and a poly(A) polymerase. Expression of the more than 200 open reading frames by vaccinia virus, the prototype poxvirus, is temporally regulated: early mRNAs are synthesized immediately after infection, whereas intermediate and late mRNAs are synthesized following genome replication. The postreplicative transcripts are heterogeneous in length and overlap the entire genome, which pose obstacles for high resolution mapping. We used tag-based methods in conjunction with high throughput cDNA sequencing to determine the precise 5'-capped and 3'-polyadenylated ends of postreplicative RNAs. Polymerase slippage during initiation of intermediate and late RNA synthesis results in a 5'-poly(A) leader that allowed the unambiguous identification of true transcription start sites. Ninety RNA start sites were located just upstream of intermediate and late open reading frames, but many more appeared anomalous, occurring within coding and non-coding regions, indicating pervasive transcription initiation. We confirmed the presence of functional promoter sequences upstream of representative anomalous start sites and demonstrated that alternative start sites within open reading frames could generate truncated isoforms of proteins. In an analogous manner, poly(A) sequences allowed accurate mapping of the numerous 3'-ends of postreplicative RNAs, which were preceded by a pyrimidine-rich sequence in the DNA coding strand. The distribution of postreplicative promoter sequences throughout the genome provides enormous transcriptional complexity, and the large number of previously unmapped RNAs may have novel functions.


Asunto(s)
Regiones no Traducidas 3'/fisiología , Genoma Viral/fisiología , Sistemas de Lectura Abierta/fisiología , ARN Viral/biosíntesis , Transcripción Genética/fisiología , Virus Vaccinia/fisiología , Replicación Viral/fisiología , Mapeo Cromosómico/métodos , Células HeLa , Humanos , ARN Viral/genética
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