Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
BMC Oral Health ; 22(1): 515, 2022 11 19.
Artículo en Inglés | MEDLINE | ID: mdl-36402972

RESUMEN

BACKGROUND: Training dental and oral health behaviors by using appropriate training models and theories is an important issue in preventing dental and oral diseases. the present study aimed to investigate the effect of training based on the health belief model and behavioral intention on dental and oral health behaviors in female students aged 9-12 years old in the city of Rudsar, Guilan, Iran. METHODS: This research is an interventional study conducted on 84 female students aged 9-12 years old, who lived in the city of Rudsar (n = 42 in the control group and n = 42 in the interventional group) in 2019. The data collection tools included questions on demographic variables, structures of the health belief model (perceived sensitivity, perceived severity, perceived barriers and benefits, self-efficiency), behavioral intention, and performance. The questionnaire was completed before the intervention and 3 months after it by both groups. The intervention group received four 45-min sessions. The data were analyzed using SPSS 24, descriptive tests, independent sample t-test, pair sample t-test, and regression (P < 0.05). RESULTS: The mean age of the intervention and control groups was 10.88 ± 1.01 and 10.80 ± 1.01, respectively. The results showed that the average scores of all structures of the health belief model and behavioral intention in the intervention group significantly changed compared to the average scores obtained before the intervention (P < 0.05). Moreover, the average scores of perceived sensitivity (p < 0.009), perceived barriers (p < 0.007), self-efficiency (p < 0.001), and behavioral intention (p < 0.001) significantly changed after the intervention in both groups (p < 0.05). CONCLUSION: According to the results, the health belief model and the behavioral intention were effective in improving dental and oral health so that they can be applied to improving people's dental and oral health. It can also be used as a model to design, implement, and monitor medical health programs.


Asunto(s)
Intención , Autocuidado , Humanos , Femenino , Niño , Irán , Conocimientos, Actitudes y Práctica en Salud , Modelo de Creencias sobre la Salud , Estudiantes
2.
Cell Syst ; 12(1): 41-55.e11, 2021 01 20.
Artículo en Inglés | MEDLINE | ID: mdl-33290741

RESUMEN

Pluripotent stem cell (PSC)-derived organoids have emerged as novel multicellular models of human tissue development but display immature phenotypes, aberrant tissue fates, and a limited subset of cells. Here, we demonstrate that integrated analysis and engineering of gene regulatory networks (GRNs) in PSC-derived multilineage human liver organoids direct maturation and vascular morphogenesis in vitro. Overexpression of PROX1 and ATF5, combined with targeted CRISPR-based transcriptional activation of endogenous CYP3A4, reprograms tissue GRNs and improves native liver functions, such as FXR signaling, CYP3A4 enzymatic activity, and stromal cell reactivity. The engineered tissues possess superior liver identity when compared with other PSC-derived liver organoids and show the presence of hepatocyte, biliary, endothelial, and stellate-like cell populations in single-cell RNA-seq analysis. Finally, they show hepatic functions when studied in vivo. Collectively, our approach provides an experimental framework to direct organogenesis in vitro by systematically probing molecular pathways and transcriptional networks that promote tissue development.


Asunto(s)
Redes Reguladoras de Genes , Organoides , Citocromo P-450 CYP3A/química , Citocromo P-450 CYP3A/genética , Redes Reguladoras de Genes/genética , Humanos , Hígado/fisiología
3.
Nat Cell Biol ; 22(9): 1143-1154, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32884147

RESUMEN

Transient modulation of the genes involved in immunity, without exerting a permanent change in the DNA code, can be an effective strategy to modulate the course of many inflammatory conditions. CRISPR-Cas9 technology represents a promising platform for achieving this goal. Truncation of guide RNA (gRNA) from the 5' end enables the application of a nuclease competent Cas9 protein for transcriptional modulation of genes, allowing multifunctionality of CRISPR. Here, we introduce an enhanced CRISPR-based transcriptional repressor to reprogram immune homeostasis in vivo. In this repressor system, two transcriptional repressors-heterochromatin protein 1 (HP1a) and Krüppel-associated box (KRAB)-are fused to the MS2 coat protein and subsequently recruited by gRNA aptamer binding to a nuclease competent CRISPR complex containing truncated gRNAs. With the enhanced repressor, we demonstrate transcriptional repression of the Myeloid differentiation primary response 88 (Myd88) gene in vitro and in vivo. We demonstrate that this strategy can efficiently downregulate Myd88 expression in lung, blood and bone marrow of Cas9 transgenic mice that receive systemic injection of adeno-associated virus (AAV)2/1-carrying truncated gRNAs targeting Myd88 and the MS2-HP1a-KRAB cassette. This downregulation is accompanied by changes in downstream signalling elements such as TNF-α and ICAM-1. Myd88 repression leads to a decrease in immunoglobulin G (IgG) production against AAV2/1 and AAV2/9 and this strategy modulates the IgG response against AAV cargos. It improves the efficiency of a subsequent AAV9/CRISPR treatment for repression of proprotein convertase subtilisin/kexin type 9 (PCSK9), a gene that, when repressed, can lower blood cholesterol levels. We also demonstrate that CRISPR-mediated Myd88 repression can act as a prophylactic measure against septicaemia in both Cas9 transgenic and C57BL/6J mice. When delivered by nanoparticles, this repressor can serve as a therapeutic modality to influence the course of septicaemia. Collectively, we report that CRISPR-mediated repression of endogenous Myd88 can effectively modulate the host immune response against AAV-mediated gene therapy and influence the course of septicaemia. The ability to control Myd88 transcript levels using a CRISPR-based synthetic repressor can be an effective strategy for AAV-based CRISPR therapies, as this pathway serves as a key node in the induction of humoral immunity against AAV serotypes.


Asunto(s)
Sistemas CRISPR-Cas/inmunología , Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/inmunología , Inmunomodulación/inmunología , Animales , Edición Génica/métodos , Células HEK293 , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Factor 88 de Diferenciación Mieloide/inmunología , Proproteína Convertasa 9 , ARN Guía de Kinetoplastida/inmunología , Receptores de Superficie Celular/inmunología
4.
Nat Commun ; 10(1): 1842, 2019 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-31015529

RESUMEN

The CRISPR-Cas9 system has raised hopes for developing personalized gene therapies for complex diseases. Its application for genetic and epigenetic therapies in humans raises concerns over immunogenicity of the bacterially derived Cas9 protein. Here we detect antibodies to Streptococcus pyogenes Cas9 (SpCas9) in at least 5% of 143 healthy individuals. We also report pre-existing human CD8+T cell immunity in the majority of healthy individuals screened. We identify two immunodominant SpCas9 T cell epitopes for HLA-A*02:01 using an enhanced prediction algorithm that incorporates T cell receptor contact residue hydrophobicity and HLA binding and evaluated them by T cell assays using healthy donor PBMCs. In a proof-of-principle study, we demonstrate that Cas9 protein can be modified to eliminate immunodominant epitopes through targeted mutation while preserving its function and specificity. Our study highlights the problem of pre-existing immunity against CRISPR-associated nucleases and offers a potential solution to mitigate the T cell immune response.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Proteína 9 Asociada a CRISPR/inmunología , Epítopos de Linfocito T/genética , Mutagénesis/inmunología , Streptococcus pyogenes/inmunología , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Células Presentadoras de Antígenos/inmunología , Proteína 9 Asociada a CRISPR/genética , Ingeniería Celular/métodos , Mapeo Epitopo/métodos , Epítopos de Linfocito T/inmunología , Terapia Genética/efectos adversos , Terapia Genética/métodos , Células HEK293 , Antígenos HLA-A/inmunología , Voluntarios Sanos , Humanos , Activación de Linfocitos/genética , Activación de Linfocitos/inmunología , Medicina de Precisión/efectos adversos , Medicina de Precisión/métodos , Streptococcus pyogenes/genética
5.
ACS Synth Biol ; 6(9): 1614-1626, 2017 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-28558198

RESUMEN

An ideal in vivo gene therapy platform provides safe, reprogrammable, and precise strategies which modulate cell and tissue gene regulatory networks with a high temporal and spatial resolution. Clustered regularly interspaced short palindromic repeats (CRISPR), a bacterial adoptive immune system, and its CRISPR-associated protein 9 (Cas9), have gained attention for the ability to target and modify DNA sequences on demand with unprecedented flexibility and precision. The precision and programmability of Cas9 is derived from its complexation with a guide-RNA (gRNA) that is complementary to a desired genomic sequence. CRISPR systems open-up widespread applications including genetic disease modeling, functional screens, and synthetic gene regulation. The plausibility of in vivo genetic engineering using CRISPR has garnered significant traction as a next generation in vivo therapeutic. However, there are hurdles that need to be addressed before CRISPR-based strategies are fully implemented. Some key issues center on the controllability of the CRISPR platform, including minimizing genomic-off target effects and maximizing in vivo gene editing efficiency, in vivo cellular delivery, and spatial-temporal regulation. The modifiable components of CRISPR systems: Cas9 protein, gRNA, delivery platform, and the form of CRISPR system delivered (DNA, RNA, or ribonucleoprotein) have recently been engineered independently to design a better genome engineering toolbox. This review focuses on evaluating CRISPR potential as a next generation in vivo gene therapy platform and discusses bioengineering advancements that can address challenges associated with clinical translation of this emerging technology.


Asunto(s)
Repeticiones Palindrómicas Cortas Agrupadas y Regularmente Espaciadas/genética , Predicción , Edición Génica/tendencias , Ingeniería Genética/tendencias , Terapia Genética/tendencias , Biología Sintética/tendencias , Animales , Medicina Basada en la Evidencia , Humanos
6.
Genom Data ; 10: 63-68, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27699151

RESUMEN

The genus Pantoea is a predominant member of host-associated microbiome. We here report on the genomic analysis of Pantoea eucrina strain Russ that was isolated from a trashcan at Oklahoma State University, Stillwater, OK. The draft genome of Pantoea eucrina strain Russ consists of 3,939,877 bp of DNA with 3704 protein-coding genes and 134 RNA genes. This is the first report of a genome sequence of a member of Pantoea eucrina. Genomic analysis revealed metabolic versatility with genes involved in the metabolism and transport of all amino acids as well as glucose, fructose, mannose, xylose, arabinose and galactose, suggesting the organism is a versatile heterotroph. The genome also encodes an extensive secretory machinery including types I, II, III, IV, and Vb secretion systems, and several genes for pili production including the new usher/chaperone system (pfam 05,229). The implications of these systems for opportunistic pathogenesis are discussed.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...