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1.
Artigo em Inglês | MEDLINE | ID: mdl-34484618

RESUMO

Background: Severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19) have caused substantial public health burdens and global health threats. Understanding the superspreading potential of a virus is important for characterizing transmission patterns and informing strategic decision-making in disease control. This systematic review aimed to summarize the existing evidence on superspreading features and to compare the heterogeneity in transmission within and among various coronavirus epidemics of SARS, MERS and COVID-19. Methods: PubMed, Medline, and Embase databases were extensively searched for original studies on the transmission heterogeneity of SARS, MERS, and COVID-19 published in English between January 1, 2003, and February 10, 2021. After screening the articles, we extracted data pertaining to the estimated dispersion parameter (k) which has been a commonly-used measurement for transmission heterogeneity and superspreading potential.FindingsWe included a total of 60 estimates of transmission heterogeneity from 26 studies on outbreaks in 22 regions. The majority (90%) of the k estimates were small, with values less than 1, indicating an over-dispersed transmission pattern. The point estimates of k for SARS and MERS ranged from 0.12 to 0.20 and from 0.06 to 2.94, respectively. Among 45 estimates of individual-level transmission heterogeneity for COVID-19 from 17 articles, 91% were derived from Asian regions. The point estimates of k for COVID-19 ranged between 0.1 and 5.0. Conclusions: We detected a substantial over-dispersed transmission pattern in all three coronaviruses, while the k estimates varied by differences in study design and public health capacity. Our findings suggested that even with a reduced R value, the epidemic still has a high resurgence potential due to transmission heterogeneity.

2.
Mol Cancer Ther ; 20(10): 1777-1788, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34376575

RESUMO

Hepatobiliary cancers are a heterogeneous group of malignancies with a dismal prognosis. Despite intensive research efforts focused on these tumors, methods for early diagnosis and effective targeted therapies are still lacking. Exosomes, released by most cells, exist in all kinds of body fluids and play an important role in cell-to-cell communication. They are small membranous vesicles containing biological molecules, such as noncoding RNAs (ncRNA), which are not translated into proteins, but they exert effects on the regulation of gene transcription and translation. There is growing evidence for the essential roles of ncRNAs in exosomes in both physiologic and pathologic conditions of hepatobiliary cancers. They have been identified as sensitive diagnostic biomarkers as well as potential therapeutic targets. The present review discusses recent findings in the cross-talk between hepatobiliary cancers cells and the surrounding cells of the microenvironment and discuss their potential clinical usage.

3.
Biomed Pharmacother ; 141: 111889, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34323697

RESUMO

Long non-coding RNA (lncRNA), a subgroup of ncRNA with a length of more than 200 nt without protein coding function, has been recognized by the academia for its mediating effects of dysregulated expression on the tumorigenesis and development of a variety of tumors. LncRNA DiGeorge syndrome critical region gene 5 (DGCR5), originally found to induce DiGeorge syndrome, has been confirmed to be extremely dysregulated in multiple tumors, which mediates the malignant phenotypes of hepatocellular carcinoma, pancreatic cancer, lung cancer, etc. through the regulation of Wnt/ß-catenin, MEK/ERK1/2 and other cancerous signaling pathways as a molecular sponge. Researches on the cancerous derivation-related pathways involved in DGCR5 can provide potential molecular intervention targets for tumor precision treatment. Moreover, liquid biopsy based on the detection of DGCR5 in body fluids is also expected to provide a non-invasive evaluation method for the early diagnosis and prognostic evaluation of malignant tumors.

4.
Biomed Pharmacother ; 138: 111529, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34311529

RESUMO

Hepatocellular carcinoma (HCC) has become a challenging disease in the world today. Due to the limitations on the current diagnosis and treatment as well as its high metastatic ability and high recurrence rate, HCC gradually becomes the second deadliest tumor. Exosomes are one of the types of cell-derived vesicles and can carry intracellular materials such as genetic materials, lipids, and proteins. In recent years, it has been verified that exosomes are linked to numerous physiological and pathological processes, including HCC. However, how exosomes affect HCC progression remains largely unknown. In this review, the exosome-mediated cellular material transfer between cells of different types in the HCC microenvironment and their effects on the behaviors and functions of recipient cells are studied. Furthermore, we also addressed the underlying molecular mechanisms. We believe that new light on the diagnosis of this cancer as well as its treatment strategies will be shed after a collation of literature in this area.


Assuntos
Carcinoma Hepatocelular/metabolismo , Comunicação Celular , Exossomos/metabolismo , Neoplasias Hepáticas/metabolismo , Microambiente Tumoral , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/terapia , Portadores de Fármacos , Exossomos/genética , Exossomos/patologia , Exossomos/transplante , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/terapia , Valor Preditivo dos Testes , Transdução de Sinais
5.
Clin Chim Acta ; 518: 93-100, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33746018

RESUMO

Circular RNA (circRNA), a newly discovered type of endogenous noncoding RNA, has become a focus and hotspot in biological research in recent years. It exists widely and possesses a stable structure, is highly conserved and has cell-specific expression. circRNA is associated with disease occurence in general and cancer specifically due to its role in cell differentiation, proliferation, invasion and metastasis. Recently, circ_ABCB10, an increasingly studied member of the annular RNA family, has attracted considerable attention due to the fact that its expression is upregulated in various tumors, ie, esophageal cancer, breast cancer, lung cancer, and glioma, and may be of prognostic value. Molecular regulation and mechanism of circ_ABCB10 action in cancer are reviewed and its potential as a molecular marker and novel target for diagnosis and treatment are explored..


Assuntos
Glioma , RNA Circular , Transportadores de Cassetes de Ligação de ATP/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Prognóstico , RNA/genética
7.
J Opt Soc Am A Opt Image Sci Vis ; 36(9): 1523-1533, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31503846

RESUMO

Obtaining accurate disparity values in textureless and texture-free regions is a very challenging task. To solve this problem, we present a novel algorithm. First, we use the guided filter method to fuse the color cost volume and the gradient cost volume. Second, we use three types of image category information to merge the different scale disparity maps and obtain the primary disparity map. Third, during the disparity refinement procedure, we also utilize the three types of category information to define different support regions and assign different weights for pixels remaining to be refined. Extensive experiments show that the performance of our method is not inferior to many state-of-the-art methods on the Middlebury data set.

8.
Org Lett ; 20(18): 5578-5582, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30179495

RESUMO

A Rh(III)-catalyzed C-H activation of boronic acid with aryl azide to obtain unsymmetric carbazoles, 1 H-indoles, or indolines has been developed. The reaction constructs dual distinct C-N bonds via sp2/sp3 C-H activation and rhodium nitrene insertion. Synthetically, this approach represents an access to widely used carbazole derivatives. The practical application to CBP and unsymmetric TCTA derivatives has also been performed. Mechanistic experiments and DFT calculations demonstrate that a five-membered rhodacycle species is the key intermediate.

9.
PLoS One ; 13(8): e0202225, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30114274

RESUMO

OBJECTIVE: To describe Chinese older adults' willingness to enter long-term care facilities and to examine individual factors associated with the willingness of using this growing model of long-term care in China. METHODS: A cross-sectional study involving a random sample of 670 adults aged 60+ in the Hezuo community in Chengdu, China in 2016. Respondents were interviewed by trained staff on socio-demographics, health status, quality of life, social support, and willingness to enter long-term care facilities. RESULTS: Only 11.9% of the respondents were willing to enter long-term care facilities for meeting their medical and social service needs. Multivariable logistic regression analysis showed that willingness to enter long-term care facilities was associated with higher household income (OR = 4.55, 95% CI:1.72-12.00), insurance of Urban Resident Basic Medical Insurance (OR = 4.80, 95% CI:1.17-19.67) and unemployment (OR = 0.48, 95% CI:0.24-0.99). Among those who were willing to enter long-term care facilities, an overwhelming majority (81.2%) would prefer going to a facility within 30-minute walking distance from their current residence, 82.5% indicated the need of nursing care, and 90.0% expected a partnership between the long-term care facility and a large hospital. CONCLUSIONS: A minority of older Chinese were willing to receive long-term care delivered at a facility within walking distance from their current residence. Recent policy aimed at increasing the supply of long-term care facilities may not be consistent with consumer preference for home and community-based care. Balancing investment between home and community-based care, and establishing long-term care insurance remain the top priorities for long-term care research and policy development in China.


Assuntos
Instituição de Longa Permanência para Idosos , Assistência de Longa Duração , Idoso , Idoso de 80 Anos ou mais , Atitude Frente a Saúde , China , Estudos Transversais , Feminino , Nível de Saúde , Humanos , Renda , Assistência de Longa Duração/psicologia , Masculino , Pessoa de Meia-Idade , Casas de Saúde , Aceitação pelo Paciente de Cuidados de Saúde/psicologia , Qualidade de Vida , Classe Social , Apoio Social , Inquéritos e Questionários
10.
Plant J ; 88(2): 318-327, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27448251

RESUMO

Legume research and cultivar development are important for sustainable food production, especially of high-protein seed. Thanks to the development of deep-sequencing technologies, crop species have been taken to the front line, even without completion of their genome sequences. Black-eyed pea (Vigna unguiculata) is a legume species widely grown in semi-arid regions, which has high potential to provide stable seed protein production in a broad range of environments, including drought conditions. The black-eyed pea reference genotype has been used to generate a gene expression atlas of the major plant tissues (i.e. leaf, root, stem, flower, pod and seed), with a developmental time series for pods and seeds. From these various organs, 27 cDNA libraries were generated and sequenced, resulting in more than one billion reads. Following filtering, these reads were de novo assembled into 36 529 transcript sequences that were annotated and quantified across the different tissues. A set of 24 866 unique transcript sequences, called Unigenes, was identified. All the information related to transcript identification, annotation and quantification were stored into a gene expression atlas webserver (http://vugea.noble.org), providing a user-friendly interface and necessary tools to analyse transcript expression in black-eyed pea organs and to compare data with other legume species. Using this gene expression atlas, we inferred details of molecular processes that are active during seed development, and identified key putative regulators of seed maturation. Additionally, we found evidence for conservation of regulatory mechanisms involving miRNA in plant tissues subjected to drought and seeds undergoing desiccation.


Assuntos
Sementes/metabolismo , Vigna/metabolismo , Mapeamento Cromossômico , Secas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas/genética , Regulação da Expressão Gênica de Plantas/fisiologia , Sementes/genética , Vigna/genética
11.
BMC Bioinformatics ; 16: 72, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25887332

RESUMO

BACKGROUND: Transposable elements constitute an important part of the genome and are essential in adaptive mechanisms. Transposition events associated with phenotypic changes occur naturally or are induced in insertional mutant populations. Transposon mutagenesis results in multiple random insertions and recovery of most/all the insertions is critical for forward genetics study. Using genome next-generation sequencing data and appropriate bioinformatics tool, it is plausible to accurately identify transposon insertion sites, which could provide candidate causal mutations for desired phenotypes for further functional validation. RESULTS: We developed a novel bioinformatics tool, ITIS (Identification of Transposon Insertion Sites), for localizing transposon insertion sites within a genome. It takes next-generation genome re-sequencing data (NGS data), transposon sequence, and reference genome sequence as input, and generates a list of highly reliable candidate insertion sites as well as zygosity information of each insertion. Using a simulated dataset and a case study based on an insertional mutant line from Medicago truncatula, we showed that ITIS performed better in terms of sensitivity and specificity than other similar algorithms such as RelocaTE, RetroSeq, TEMP and TIF. With the case study data, we demonstrated the efficiency of ITIS by validating the presence and zygosity of predicted insertion sites of the Tnt1 transposon within a complex plant system, M. truncatula. CONCLUSION: This study showed that ITIS is a robust and powerful tool for forward genetic studies in identifying transposable element insertions causing phenotypes. ITIS is suitable in various systems such as cell culture, bacteria, yeast, insect, mammal and plant.


Assuntos
Elementos de DNA Transponíveis , Sequenciamento de Nucleotídeos em Larga Escala , Análise de Sequência de DNA , Software , Algoritmos , Biologia Computacional/métodos , Medicago truncatula/genética
12.
Ann Bot ; 113(6): 921-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24573642

RESUMO

BACKGROUND AND AIMS: Seed yield and dormancy status are key components of species fitness that are influenced by the maternal environment, in particular temperature. Responses to environmental conditions can differ between ecotypes of the same species. Therefore, to investigate the effect of maternal environment on seed production, this study compared two contrasting Arabidopsis thaliana ecotypes, Cape Verdi Isle (Cvi) and Burren (Bur). Cvi is adapted to a hot dry climate and Bur to a cool damp climate, and they exhibit winter and summer annual phenotypes, respectively. METHODS: Bur and Cvi plants were grown in reciprocal controlled environments that simulated their native environments. Reproductive development, seed production and subsequent germination behaviour were investigated. Measurements included: pollen viability, the development of floral structure, and germination at 10 and 25 °C in the light to determine dormancy status. Floral development was further investigated by applying gibberellins (GAs) to alter the pistil:stamen ratio. KEY RESULTS: Temperature during seed development determined seed dormancy status. In addition, seed yield was greatly reduced by higher temperature, especially in Bur (>90 %) compared with Cvi (approx. 50 %). The reproductive organs (i.e. stamens) of Bur plants were very sensitive to high temperature during early flowering. Viability of pollen was unaffected, but limited filament extension relative to that of the pistils resulted in failure to pollinate. Thus GA applied to flowers to enhance filament extension largely overcame the effect of high temperature on yield. CONCLUSIONS: High temperature in the maternal environment reduced dormancy and negatively affected the final seed yield of both ecotypes; however, the extent of these responses differed, demonstrating natural variation. Reduced seed yield in Bur resulted from altered floral development not reduced pollen viability. Future higher temperatures will impact on seed performance, but the consequences may differ significantly between ecotypes of the same species.


Assuntos
Arabidopsis/fisiologia , Estações do Ano , Temperatura , Arabidopsis/classificação , Arabidopsis/crescimento & desenvolvimento , Flores/crescimento & desenvolvimento , Germinação , Reprodução
13.
Plant J ; 74(6): 1003-15, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23590427

RESUMO

Seeds use environmental cues to sense the seasons and their surroundings to initiate the life cycle of the plant. The dormancy cycling underlying this process is extensively described, but the molecular mechanism is largely unknown. To address this we selected a range of representative genes from published array experiments in the laboratory, and investigated their expression patterns in seeds of Arabidopsis ecotypes with contrasting life cycles over an annual dormancy cycle in the field. We show how mechanisms identified in the laboratory are coordinated in response to the soil environment to determine the dormancy cycles that result in winter and summer annual phenotypes. Our results are consistent with a seed-specific response to seasonal temperature patterns (temporal sensing) involving the gene DELAY OF GERMINATION 1 (DOG1) that indicates the correct season, and concurrent temporally driven co-opted mechanisms that sense spatial signals, i.e. nitrate, via CBL-INTERACTING PROTEIN KINASE 23 (CIPK23) phosphorylation of the NITRATE TRANSPORTER 1 (NRT1.1), and light, via PHYTOCHROME A (PHYA). In both ecotypes studied, when all three genes have low expression there is enhanced GIBBERELLIN 3 BETA-HYDROXYLASE 1 (GA3ox1) expression, exhumed seeds have the potential to germinate in the laboratory, and the initiation of seedling emergence occurs following soil disturbance (exposure to light) in the field. Unlike DOG1, the expression of MOTHER of FLOWERING TIME (MFT) has an opposite thermal response in seeds of the two ecotypes, indicating a role in determining their different dormancy cycling phenotypes.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Regulação da Expressão Gênica de Plantas , Dormência de Plantas , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Transporte , Análise por Conglomerados , Meio Ambiente , Germinação , Peptídeos e Proteínas de Sinalização Intracelular , Luz , Nitratos/metabolismo , Especificidade de Órgãos , Fenótipo , Estações do Ano , Plântula/genética , Plântula/fisiologia , Sementes/genética , Sementes/fisiologia , Transdução de Sinais , Solo , Temperatura , Fatores de Tempo
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