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1.
J Virol ; 97(8): e0014823, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37565749

RESUMO

Human cytomegalovirus (HCMV) is a beta herpesvirus that persists indefinitely in the human host through a latent infection. The polycistronic UL133-UL138 gene locus of HCMV encodes genes regulating latency and reactivation. While UL138 is pro-latency, restricting virus replication in CD34+ hematopoietic progenitor cells (HPCs), UL135 overcomes this restriction and is required for reactivation. By contrast, UL136 is expressed with later kinetics and encodes multiple proteins with differential roles in latency and reactivation. Like UL135, the largest UL136 isoform, UL136p33, is required for reactivation from latency in HPCs; viruses failing to express either protein are unresponsive to reactivation stimuli. Furthermore, UL136p33 is unstable, and its instability is important for the establishment of latency, and sufficient accumulation of UL136p33 is a checkpoint for reactivation. We hypothesized that stabilizing UL136p33 might overcome the requirement of UL135 for replication. We generated recombinant viruses lacking UL135 that expressed a stabilized variant of UL136p33. Stabilizing UL136p33 did not impact the replication of the UL135 mutant virus in fibroblasts. However, in the context of infection in HPCs, stabilization of UL136p33 strikingly compensated for the loss of UL135, resulting in increased replication in CD34+ HPCs and in humanized NOD-scid IL2Rγcnull (huNSG) mice. This finding suggests that while UL135 is essential for replication in HPCs, it functions largely at steps preceding the accumulation of UL136p33, and that stabilized expression of UL136p33 largely overcomes the requirement for UL135. Taken together, our genetic evidence indicates an epistatic relationship between UL136p33 and UL135, whereby UL135 may initiate events early in reactivation that drive the accumulation of UL136p33 to a threshold required for productive reactivation. IMPORTANCE Human cytomegalovirus (HCMV) is one of nine human herpesviruses and a significant human pathogen. While HCMV establishes a lifelong latent infection that is typically asymptomatic in healthy individuals, its reactivation from latency can have devastating consequences in the immunocompromised. Defining viral genes important in the establishment of or reactivation from latency is important to defining the molecular basis of latent and replicative states and in controlling infection and CMV disease. Here we define a genetic relationship between two viral genes in controlling virus reactivation from latency using primary human hematopoietic progenitor cells and humanized mouse models.


Assuntos
Citomegalovirus , Infecção Latente , Animais , Humanos , Camundongos , Antígenos CD34/genética , Antígenos CD34/metabolismo , Citomegalovirus/fisiologia , Camundongos Endogâmicos NOD , Proteínas Virais/genética , Proteínas Virais/metabolismo , Latência Viral , Replicação Viral
2.
Ecotoxicol Environ Saf ; 256: 114866, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37023649

RESUMO

The multifarious problems created by arsenic (As), for collective environment and human health, serve a cogent case for searching integrative agricultural approaches to attain food security. Rice (Oryza sativa L.) acts as a sponge for heavy metal(loid)s accretion, specifically As, due to anaerobic flooded growth conditions facilitating its uptake. Acclaimed for their positive impact on plant growth, development and phosphorus (P) nutrition, 'mycorrhizas' are able to promote stress tolerance. Albeit, the metabolic alterations underlying Serendipita indica (S. indica; S.i) symbiosis-mediated amelioration of As stress along with nutritional management of P are still understudied. By using biochemical, RT-qPCR and LC-MS/MS based untargeted metabolomics approach, rice roots of ZZY-1 and GD-6 colonized by S. indica, which were later treated with As (10 µM) and P (50 µM), were compared with non-colonized roots under the same treatments with a set of control plants. The responses of secondary metabolism related enzymes, especially polyphenol oxidase (PPO) activities in the foliage of ZZY-1 and GD-6 were enhanced 8.5 and 12-fold, respectively, compared to their respective control counterparts. The current study identified 360 cationic and 287 anionic metabolites in rice roots, and the commonly enriched pathway annotated by Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis was biosynthesis of phenylalanine, tyrosine and tryptophan, which validated the results of biochemical and gene expression analyses associated with secondary metabolic enzymes. Particularly under As+S.i+P comparison, both genotypes exhibited an upregulation of key detoxification and defense related metabolites, including fumaric acid, L-malic acid, choline, 3,4-dihydroxybenzoic acid, to name a few. The results of this study provided the novel insights into the promising role of exogenous P and S. indica in alleviating As stress.


Assuntos
Arsênio , Oryza , Fósforo , Poluentes do Solo , Humanos , Arsênio/toxicidade , Cromatografia Líquida , Oryza/metabolismo , Oryza/microbiologia , Fósforo/análise , Raízes de Plantas/metabolismo , Metabolismo Secundário , Espectrometria de Massas em Tandem , Poluentes do Solo/toxicidade
3.
Acta Trop ; 205: 105354, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31982433

RESUMO

INTRODUCTION: Cystic echinococcosis (CE) is a parasitic zoonotic disease caused by the larval stage of Echinococcus granulosus tapeworms. It has a worldwide geographic distribution and can threaten the livestock industry and human health in endemic areas, including Pakistan. CE prevalence is high in Pakistan due to lack of local knowledge about disease transmission and a lack of control measures. The Pakistan province of Baluchistan shares a border with Iran and Afghanistan and is largely agricultural. However, little is known about E. granulosus transmission in this region. METHODS: Information on surgically confirmed cases of CE in Baluchistan Province was obtained through evaluation of paraffin fixed cyst samples and patient records obtained from three local hospitals for the years 2011-2018. RESULTS: A total of 22 paraffin fixed samples were collected during the study period. The majority of cysts were obtained from the liver (9/22; 40.9%), with anatomical location not available for two of the cysts. Demographic information was available for 18 cases. Females made up 61.1% (11/18) of the cases. The largest numbers of cases were found in the 31-40 years age group (5/18; 22.7%). DISCUSSION: This study shows that Echinococcus spp. parasites are circulating in the study area. In order to control the disease, a comprehensive regional surveillance and control program is needed.


Assuntos
Equinococose/epidemiologia , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Equinococose/prevenção & controle , Echinococcus granulosus , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Fatores de Tempo , Adulto Jovem
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