Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 53
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
BMC Bioinformatics ; 24(1): 341, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37704952

RESUMO

BACKGROUND: Mitochondria are the cell organelles that produce most of the chemical energy required to power the cell's biochemical reactions. Despite being a part of a eukaryotic host cell, the mitochondria contain a separate genome whose origin is linked with the endosymbiosis of a prokaryotic cell by the host cell and encode independent genomic information throughout their genomes. Mitochondrial genomes accommodate essential genes and are regularly utilized in biotechnology and phylogenetics. Various assemblers capable of generating complete mitochondrial genomes are being continuously developed. These tools often use whole-genome sequencing data as an input containing reads from the mitochondrial genome. Till now, no published work has explored the systematic comparison of all the available tools for assembling human mitochondrial genomes using short-read sequencing data. This evaluation is required to identify the best tool that can be well-optimized for small-scale projects or even national-level research. RESULTS: In this study, we have tested the mitochondrial genome assemblers for both simulated datasets and whole genome sequencing (WGS) datasets of humans. For the highest computational setting of 16 computational threads with the simulated dataset having 1000X read depth, MitoFlex took the least execution time of 69 s, and IOGA took the longest execution time of 1278 s. NOVOPlasty utilized the least computational memory of approximately 0.098 GB for the same setting, whereas IOGA utilized the highest computational memory of 11.858 GB. In the case of WGS datasets for humans, GetOrganelle and MitoFlex performed the best in capturing the SNPs information with a mean F1-score of 0.919 at the sequencing depth of 10X. MToolBox and NOVOPlasty performed consistently across all sequencing depths with a mean F1 score of 0.897 and 0.890, respectively. CONCLUSIONS: Based on the overall performance metrics and consistency in assembly quality for all sequencing data, MToolBox performed the best. However, NOVOPlasty was the second fastest tool in execution time despite being single-threaded, and it utilized the least computational resources among all the assemblers when tested on simulated datasets. Therefore, NOVOPlasty may be more practical when there is a significant sample size and a lack of computational resources. Besides, as long-read sequencing gains popularity, mitochondrial genome assemblers must be developed to use long-read sequencing data.


Assuntos
Genoma Mitocondrial , Humanos , Genoma Humano , Mitocôndrias/genética , Benchmarking , Biotecnologia
2.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203678

RESUMO

RNA pol II assembly occurs in the cytoplasm before translocation of the enzyme to the nucleus. Affecting this assembly influences mRNA transcription in the nucleus and mRNA decay in the cytoplasm. However, very little is known about the consequences on ncRNA synthesis. In this work, we show that impairment of RNA pol II assembly leads to a decrease in cryptic non-coding RNAs (preferentially CUTs and SUTs). This alteration is partially restored upon overcoming the assembly defect. Notably, this drop in ncRNAs is only partially dependent on the nuclear exosome, which suggests a major specific effect of enzyme assembly. Our data also point out a defect in transcription termination, which leads us to propose that CTD phosphatase Rtr1 could be involved in this process.


Assuntos
Exossomos , RNA Polimerase II , Humanos , RNA Polimerase II/genética , Transcrição Gênica , RNA não Traduzido/genética , Translocação Genética
3.
J Gen Intern Med ; 37(5): 1169-1176, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34993856

RESUMO

BACKGROUND: There is a paucity of data on the mental health impact of the Coronavirus disease 2019 (COVID-19) pandemic on United States (US) healthcare workers (HCWs) after the first surge in the spring of 2020. OBJECTIVE: To determine the impact of the pandemic on HCWs, and the relationship between HCW mental health and demographics, occupational factors, and COVID-19 concerns. DESIGN: Cross-sectional survey in an urban medical center (September-November 2020) in Baltimore, MD, in the United States. PARTICIPANTS: A total of 605 HCWs (physicians, nurse practitioners, nurses, physician assistants, patient care technicians, respiratory therapists, social workers, mental health therapists, and case managers). MAIN MEASURES: Measures of mental health (Patient Health Questionnaire-2, Generalized Anxiety Disorder-7, PROMIS Sleep Disturbance 4a, Impact of Event Scale-Revised, Maslach Burnout Inventory-2 item, Connor-Davidson Resilience Scale-2 item), demographics, occupational factors, and COVID-19 related concerns. KEY RESULTS: Fifty-two percent of 1198 HCWs responded to the survey and 14.2% reported depression, 43.1% mild or higher anxiety, 31.6% sleep disturbance, 22.3% posttraumatic stress symptoms, 21.6% depersonalization, 46.0% emotional exhaustion, and 23.1% lower resilience. Relative to HCWs providing in-person care to COVID-19 infected patients none of their working days, those doing so all or most days were more likely to experience worse depression (adjusted odds ratio, 3.9; 95% CI, 1.3-11.7), anxiety (aOR, 3.0; 95% CI, 1.4-6.3), possible PTSD symptoms (aOR, 2.6; 95% CI, 1.1-5.8), and higher burnout (aOR, 2.6; 95% CI, 1.1-6.0). Worse mental health in several domains was associated with higher health fear (aORs ranged from 2.2 to 5.0), job stressors (aORs ranged from 1.9 to 4.0), perceived social stigma/avoidance (aORs ranged from 1.8 to 2.9), and workplace safety concerns (aORs ranged from 1.8 to 2.8). CONCLUSIONS: US HCWs experienced significant mental health symptoms eight months into the pandemic. More time spent providing in-person care to COVID-19-infected patients and greater COVID-19-related concerns were consistently associated with worse mental health.


Assuntos
COVID-19 , Ansiedade/epidemiologia , Ansiedade/psicologia , COVID-19/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Pessoal de Saúde/psicologia , Humanos , Saúde Mental , Pandemias , SARS-CoV-2 , Estados Unidos/epidemiologia
4.
Indian J Med Res ; 155(5&6): 546-553, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36348601

RESUMO

Background & objectives: High mortality has been observed in the cancer population affected with COVID-19 during this pandemic. We undertook this study to determine the characteristics and outcomes of cancer patients with COVID-19 and assessed the factors predicting outcome. Methods: Patients of all age groups with a proven history of malignancy and a recent diagnosis of SARS-CoV-2 infection based on nasal/nasopharyngeal reverse transcriptase (RT)-PCR tests were included. Demographic, clinical and laboratory variables were compared between survivors and non-survivors groups, with respect to observed mortality. Results: Between May 11 and August 10, 2020, 134 patients were included from the three centres and observed mortality was 17.1 per cent. The median age was 53 yr (interquartile range 39-61 yr) and thirty four patients (25%) were asymptomatic. Solid tumours accounted for 69.1 per cent and breast cancer was the most common tumour type (20%). One hundred and five patients (70.5%) had received chemotherapy within the past four weeks and 25 patients (19.3%) had neutropenia at presentation. On multivariate analysis, age [odds ratio (OR) 7.99 (95% confidence interval [CI] 1.18-54.00); P=0.033], haemoglobin [OR 6.28 (95% CI 1.07-37.04); P=0.042] neutrophil-lymphocyte ratio [OR 12.02 (95% CI 2.08-69.51); P=0.005] and baseline serum albumin [OR 18.52 (95% CI 2.80-122.27); P=0.002], were associated with higher mortality. Recent chemotherapy, haematological tumours type and baseline neutropenia did not affect the outcome. Interpretation & conclusions: Higher mortality in moderate and severe infections was associated with baseline organ dysfunction and elderly age. Significant proportion of patients were asymptomatic and might remain undetected.


Assuntos
COVID-19 , Neoplasias , Neutropenia , Humanos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2 , Índia/epidemiologia , Neoplasias/complicações , Neoplasias/epidemiologia , Neutropenia/complicações
5.
Neurobiol Dis ; 148: 105217, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33301878

RESUMO

More than forty loci contribute to genetic risk for Alzheimer's disease (AD). These risk alleles are enriched in myeloid cell enhancers suggesting that microglia, the brain-resident macrophages, contribute to AD risk. We have previously identified SPI1/PU.1, a master regulator of myeloid cell development in the brain and periphery, as a genetic risk factor for AD. Higher expression of SPI1 is associated with increased risk for AD, while lower expression is protective. To investigate the molecular and cellular phenotypes associated with higher and lower expression of PU.1 in microglia, we used stable overexpression and knock-down of PU.1 in BV2, an immortalized mouse microglial cell line. Transcriptome analysis suggests that reduced PU.1 expression suppresses expression of homeostatic genes similar to the disease-associated microglia response to amyloid plaques in mouse models of AD. Moreover, PU.1 knock-down resulted in activation of protein translation, antioxidant action and cholesterol/lipid metabolism pathways with a concomitant decrease of pro-inflammatory gene expression. PU.1 overexpression upregulated and knock-down downregulated phagocytic uptake in BV2 cells independent of the nature of the engulfed material. However, cells with reduced PU.1 expression retained their ability to internalize myelin similar to control albeit with a delay, which aligns with their anti-inflammatory profile. Here we identified several microglial responses that are modulated by PU.1 expression levels and propose that risk association of PU.1 to AD is driven by increased pro-inflammatory response due to increased viability of cells under cytotoxic conditions. In contrast, low expression of PU.1 leads to increased cell death under cytotoxic conditions accompanied by reduced pro-inflammatory signaling that decreased A1 reactive astrocytes signature supporting the protective effect of SPI1 genotype in AD. These findings inform future in vivo validation studies and design of small molecule screens for therapeutic discovery in AD.


Assuntos
Doença de Alzheimer/genética , Apoptose/genética , Inflamação/genética , Microglia/metabolismo , Proteínas Proto-Oncogênicas/genética , Transativadores/genética , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular , Citocinas/efeitos dos fármacos , Citocinas/metabolismo , Perfilação da Expressão Gênica , Técnicas de Silenciamento de Genes , Inflamação/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Microglia/efeitos dos fármacos , Óxido Nítrico/metabolismo , Fragmentos de Peptídeos/farmacologia , Rotenona/farmacologia , Estaurosporina , Desacopladores/farmacologia
6.
Gastroenterology ; 159(2): 624-638.e9, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32289375

RESUMO

BACKGROUND & AIMS: In response to tissue injury, stromal cells secrete extracellular matrix (ECM) components that remodel the tissue and lead to fibrosis. Parenchymal stellate cells are the primary contributors to fibrosis in models of hepatocellular and cholestatic injury. The liver comprises different, heterogenous compartments; stromal cells within those compartments might have unique identities and regional functions. The portal tract contains the bile duct, which is surrounded by stromal cells often called portal fibroblasts. We investigated the contributions of these cells to hepatic injury. METHODS: We performed studies with Gli1:CreERT2;Rosa26:lox-STOP-lox-tdTomato mice. Mice underwent bile duct ligation or were fed 3,5-diethoxycarbonyl-1,4-dihydrocollidine to induce cholestatic injury or were given carbon tetrachloride to induce liver fibrosis. Liver tissues were collected and analyzed by histology and immunofluorescence, and mesenchymal cells were isolated. We performed lineage tracing experiments to determine the fates of peribiliary mesenchymal cells (PMCs) that surround the bile duct after cholestatic and hepatocellular injury. We used cell sorting combined with RNA sequencing to isolate stellate cells and PMCs, and we identified determinants of cell identity within each population. Liver tissues were obtained from patients with primary sclerosing cholangitis, alcoholic liver disease, or nonalcoholic steatohepatitis or individuals without disease and were analyzed by quantitative reverse transcription polymerase chain reaction. RESULTS: Gli1 was a marker of mesenchymal cells that surround the biliary tree but not epithelial cells of the canals of Hering. Lineage-traced Gli1+ PMCs proliferated and acquired a myofibroblast phenotype after cholestatic injury; Gli1+ PMCs were found only surrounding the main duct of a portal tract but not the epithelial cells of the ductular reaction, which were instead encased by stellate cells. Compared with stellate cells, Gli1+ PMCs expressed a different subset of genes, including genes that are markers of active hedgehog signaling, Osr1 (encodes a transcription factor), and ECM-related genes. Loss of hedgehog signaling reduced expression of Osr1 and PMC-specific ECM genes. Liver tissues from patients with liver disease had increased expression of genes that define PMC identity compared with control liver tissues. CONCLUSIONS: In lineage-tracing studies of mice, we found that Gli1+ PMCs are a subset of stromal cells characterized by active hedgehog signaling that proliferate, acquire a myofibroblast phenotype, and surround the biliary tree in response to cholestatic injury.


Assuntos
Colestase/patologia , Proteínas Hedgehog/metabolismo , Cirrose Hepática Experimental/patologia , Células-Tronco Mesenquimais/patologia , Animais , Tetracloreto de Carbono/toxicidade , Feminino , Fibroblastos/patologia , Humanos , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Masculino , Camundongos , Camundongos Transgênicos , Transdução de Sinais , Nicho de Células-Tronco , Proteína GLI1 em Dedos de Zinco/metabolismo
7.
Genome Res ; 28(2): 231-242, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29196558

RESUMO

Understanding transcriptome complexity is crucial for understanding human biology and disease. Technologies such as Synthetic long-read RNA sequencing (SLR-RNA-seq) delivered 5 million isoforms and allowed assessing splicing coordination. Pacific Biosciences and Oxford Nanopore increase throughput also but require high input amounts or amplification. Our new droplet-based method, sparse isoform sequencing (spISO-seq), sequences 100k-200k partitions of 10-200 molecules at a time, enabling analysis of 10-100 million RNA molecules. SpISO-seq requires less than 1 ng of input cDNA, limiting or removing the need for prior amplification with its associated biases. Adjusting the number of reads devoted to each molecule reduces sequencing lanes and cost, with little loss in detection power. The increased number of molecules expands our understanding of isoform complexity. In addition to confirming our previously published cases of splicing coordination (e.g., BIN1), the greater depth reveals many new cases, such as MAPT Coordination of internal exons is found to be extensive among protein coding genes: 23.5%-59.3% (95% confidence interval) of highly expressed genes with distant alternative exons exhibit coordination, showcasing the need for long-read transcriptomics. However, coordination is less frequent for noncoding sequences, suggesting a larger role of splicing coordination in shaping proteins. Groups of genes with coordination are involved in protein-protein interactions with each other, raising the possibility that coordination facilitates complex formation and/or function. We also find new splicing coordination types, involving initial and terminal exons. Our results provide a more comprehensive understanding of the human transcriptome and a general, cost-effective method to analyze it.


Assuntos
Processamento Alternativo/genética , Microfluídica/métodos , Splicing de RNA/genética , Transcriptoma/genética , Biologia Computacional , Regulação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Anotação de Sequência Molecular , Isoformas de Proteínas/genética , Análise de Sequência de RNA
8.
J Exp Bot ; 72(6): 2212-2230, 2021 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-33197257

RESUMO

Rice, a staple food worldwide, contains varying amounts of nutrients in different grain tissues. The underlying molecular mechanism of such distinct nutrient partitioning remains poorly investigated. Here, an optimized rapid laser capture microdissection (LCM) approach was used to individually collect pericarp, aleurone, embryo and endosperm from grains 10 days after fertilization. Subsequent RNA-Seq analysis in these tissues identified 7760 differentially expressed genes. Analysis of promoter sequences of tissue-specific genes identified many known and novel cis-elements important for grain filling and seed development. Using the identified differentially expressed genes, comprehensive spatial gene expression pathways were built for accumulation of starch, proteins, lipids, and iron. The extensive transcriptomic analysis provided novel insights about nutrient partitioning mechanisms; for example, it revealed a gradient in seed storage protein accumulation across the four tissue types analysed. The analysis also revealed that the partitioning of various minerals, such as iron, is most likely regulated through transcriptional control of their transporters. We present the extensive analysis from this study as an interactive online tool that provides a much-needed resource for future functional genomics studies aimed to improve grain quality and seed development.


Assuntos
Oryza , Grão Comestível/genética , Grão Comestível/metabolismo , Endosperma/genética , Endosperma/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Nutrientes , Oryza/genética , Oryza/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sementes/genética , Sementes/metabolismo
9.
Mol Cell ; 47(2): 267-80, 2012 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-22683267

RESUMO

Poly(A) (pA) tail binding proteins (PABPs) control mRNA polyadenylation, stability, and translation. In a purified system, S. cerevisiae PABPs, Pab1p and Nab2p, are individually sufficient to provide normal pA tail length. However, it is unknown how this occurs in more complex environments. Here we find that the nuclear exosome subunit Rrp6p counteracts the in vitro and in vivo extension of mature pA tails by the noncanonical pA polymerase Trf4p. Moreover, PABP loading onto nascent pA tails is controlled by Rrp6p; while Pab1p is the major PABP, Nab2p only associates in the absence of Rrp6p. This is because Rrp6p can interact with Nab2p and displace it from pA tails, potentially leading to RNA turnover, as evidenced for certain pre-mRNAs. We suggest that a nuclear mRNP surveillance step involves targeting of Rrp6p by Nab2p-bound pA-tailed RNPs and that pre-mRNA abundance is regulated at this level.


Assuntos
Exorribonucleases/metabolismo , Poli A/química , Proteínas de Ligação a Poli(A)/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Bases , Núcleo Celular/metabolismo , Citoplasma/metabolismo , DNA Polimerase Dirigida por DNA/metabolismo , Complexo Multienzimático de Ribonucleases do Exossomo , Exossomos/metabolismo , Regulação Fúngica da Expressão Gênica , Modelos Biológicos , Dados de Sequência Molecular , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Poli A/genética , Ligação Proteica , RNA/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo
10.
Nucleic Acids Res ; 43(2): 787-802, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25550430

RESUMO

The particular behaviour of eukaryotic RNA polymerases along different gene regions and amongst distinct gene functional groups is not totally understood. To cast light onto the alternative active or backtracking states of RNA polymerase II, we have quantitatively mapped active RNA polymerases at a high resolution following a new biotin-based genomic run-on (BioGRO) technique. Compared with conventional profiling with chromatin immunoprecipitation, the analysis of the BioGRO profiles in Saccharomyces cerevisiae shows that RNA polymerase II has unique activity profiles at both gene ends, which are highly dependent on positioned nucleosomes. This is the first demonstration of the in vivo influence of positioned nucleosomes on transcription elongation. The particular features at the 5' end and around the polyadenylation site indicate that this polymerase undergoes extensive specific-activity regulation in the initial and final transcription elongation phases. The genes encoding for ribosomal proteins show distinctive features at both ends. BioGRO also provides the first nascentome analysis for RNA polymerase III, which indicates that transcription of tRNA genes is poorly regulated at the individual copy level. The present study provides a novel perspective of the transcription cycle that incorporates inactivation/reactivation as an important aspect of RNA polymerase dynamics.


Assuntos
Nucleossomos/metabolismo , RNA Polimerase III/metabolismo , RNA Polimerase II/metabolismo , Transcrição Gênica , Genoma Fúngico , Genômica/métodos , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Elongação da Transcrição Genética , Terminação da Transcrição Genética
11.
PLoS Genet ; 10(10): e1004569, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25340856

RESUMO

Recent studies have suggested that a sub-complex of RNA polymerase II composed of Rpb4 and Rpb7 couples the nuclear and cytoplasmic stages of gene expression by associating with newly made mRNAs in the nucleus, and contributing to their translation and degradation in the cytoplasm. Here we show by yeast two hybrid and co-immunoprecipitation experiments, followed by ribosome fractionation and fluorescent microscopy, that a subunit of the Ccr4-Not complex, Not5, is essential in the nucleus for the cytoplasmic functions of Rpb4. Not5 interacts with Rpb4; it is required for the presence of Rpb4 in polysomes, for interaction of Rpb4 with the translation initiation factor eIF3 and for association of Rpb4 with mRNAs. We find that Rpb7 presence in the cytoplasm and polysomes is much less significant than that of Rpb4, and that it does not depend upon Not5. Hence Not5-dependence unlinks the cytoplasmic functions of Rpb4 and Rpb7. We additionally determine with RNA immunoprecipitation and native gel analysis that Not5 is needed in the cytoplasm for the co-translational assembly of RNA polymerase II. This stems from the importance of Not5 for the association of the R2TP Hsp90 co-chaperone with polysomes translating RPB1 mRNA to protect newly synthesized Rpb1 from aggregation. Hence taken together our results show that Not5 interconnects translation and transcription.


Assuntos
Biossíntese de Proteínas , RNA Mensageiro/genética , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/genética , Transcrição Gênica , Núcleo Celular/genética , Citoplasma/genética , Fator de Iniciação 3 em Eucariotos/genética , Regulação Fúngica da Expressão Gênica , Polirribossomos/genética , RNA Polimerase II/genética , Estabilidade de RNA , Saccharomyces cerevisiae , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo
12.
Mol Syst Biol ; 11(1): 777, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25583149

RESUMO

We present a modified approach of chromatin immuno-precipitation followed by sequencing (ChIP-Seq), which relies on the direct ligation of molecular barcodes to chromatin fragments, thereby permitting experimental scale-up. With Bar-ChIP now enabling the concurrent profiling of multiple DNA-protein interactions, we report the simultaneous generation of 90 ChIP-Seq datasets without any robotic instrumentation. We demonstrate that application of Bar-ChIP to a panel of Saccharomyces cerevisiae chromatin-associated mutants provides a rapid and accurate genome-wide overview of their chromatin status. Additionally, we validate the utility of this technology to derive novel biological insights by identifying a role for the Rpd3S complex in maintaining H3K14 hypo-acetylation in gene bodies. We also report an association between the presence of intragenic H3K4 tri-methylation and the emergence of cryptic transcription in a Set2 mutant. Finally, we uncover a crosstalk between H3K14 acetylation and H3K4 methylation in this mutant. These results show that Bar-ChIP enables biological discovery through rapid chromatin profiling at single-nucleosome resolution for various conditions and protein modifications at once.


Assuntos
Imunoprecipitação da Cromatina/métodos , Cromatina/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Acetilação , Cromatina/química , DNA Fúngico/genética , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Estudos de Associação Genética , Marcadores Genéticos , Histonas/genética , Histonas/metabolismo , Metilação , Nucleossomos , Reprodutibilidade dos Testes , Saccharomyces cerevisiae/genética , Alinhamento de Sequência , Análise de Sequência de DNA
13.
Mol Syst Biol ; 10: 719, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24569168

RESUMO

Recent research has uncovered extensive variability in the boundaries of transcript isoforms, yet the functional consequences of this variation remain largely unexplored. Here, we systematically discriminate between the molecular phenotypes of overlapping coding and non-coding transcriptional events from each genic locus using a novel genome-wide, nucleotide-resolution technique to quantify the half-lives of 3' transcript isoforms in yeast. Our results reveal widespread differences in stability among isoforms for hundreds of genes in a single condition, and that variation of even a single nucleotide in the 3' untranslated region (UTR) can affect transcript stability. While previous instances of negative associations between 3' UTR length and transcript stability have been reported, here, we find that shorter isoforms are not necessarily more stable. We demonstrate the role of RNA-protein interactions in conditioning isoform-specific stability, showing that PUF3 binds and destabilizes specific polyadenylation isoforms. Our findings indicate that although the functional elements of a gene are encoded in DNA sequence, the selective incorporation of these elements into RNA through transcript boundary variation allows a single gene to have diverse functional consequences.


Assuntos
Processamento Pós-Transcricional do RNA/genética , Proteínas de Ligação a RNA/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Regiões 3' não Traduzidas/genética , Poliadenilação , Estabilidade de RNA/genética , Proteínas de Ligação a RNA/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo
14.
NAR Genom Bioinform ; 6(2): lqae047, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38774511

RESUMO

With an increase in accuracy and throughput of long-read sequencing technologies, they are rapidly being assimilated into the single-cell sequencing pipelines. For transcriptome sequencing, these techniques provide RNA isoform-level information in addition to the gene expression profiles. Long-read sequencing technologies not only help in uncovering complex patterns of cell-type specific splicing, but also offer unprecedented insights into the origin of cellular complexity and thus potentially new avenues for drug development. Additionally, single-cell long-read DNA sequencing enables high-quality assemblies, structural variant detection, haplotype phasing, resolving high-complexity regions, and characterization of epigenetic modifications. Given that significant progress has primarily occurred in single-cell RNA isoform sequencing (scRiso-seq), this review will delve into these advancements in depth and highlight the practical considerations and operational challenges, particularly pertaining to downstream analysis. We also aim to offer a concise introduction to complementary technologies for single-cell sequencing of the genome, epigenome and epitranscriptome. We conclude by identifying certain key areas of innovation that may drive these technologies further and foster more widespread application in biomedical science.

15.
Mayo Clin Proc Innov Qual Outcomes ; 8(1): 37-44, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38259804

RESUMO

Objective: To determine the change in rates of physical restraint (PR) use and associated outcomes among hospitalized adults. Patients and Methods: Using national inpatient sample databases, we analyzed years 2011-2014 and 2016-2019 to determine trends of PR usage. We also compared the years 2011-2012 and 2018-2019 to investigate rates of PR use, in-hospital mortality, length of stay, and total hospital charges. Results: There were 242,994,110 hospitalizations during the study period. 1,538,791 (0.63%) had coding to signify PRs, compared with 241,455,319 (99.3%), which did not. From 2011 to 2014, there was a significant increase in PR use (p-trend<.01) and a nonsignificant increase in PR rates from 2016-2019 (p-trend=.07). Over time, PR use increased (2011-2012: 0.52% vs 2018-2019: 0.73%; p<.01). Patients with PRs reported a higher adjusted odds for in-hospital mortality in 2011-2012 (adjusted odds ratio [aOR], 3.9; 95% CI, 3.7-4.2; p<.01) and 2018-2019 (aOR, 3.5; 95% CI, 3.4-3.7; p<.01). Length of stay was prolonged for patients with PRs in 2011-2012 (adjusted mean difference [aMD], 4.3 days; 95% CI, 4.1-4.5; p<.01) and even longer in 2018-2019 (aMD, 5.8 days; 95% CI, 5.6-6.0; p<.01). Total hospital charges were higher for patients with PRs in 2011-2012 (aMD, +$55,003; 95% CI, $49,309-$60,679; p<.01). Following adjustment for inflation, total charges remained higher for patients with PRs compared with those without PRs in 2018-2019 (aMD, +$70,018; 95% CI, $65,355-$74,680; p<.01). Conclusion: Overall, PR rates did not decrease across the study period, suggesting that messaging and promulgating best practice guidelines have yet to translate into a substantive change in practice patterns.

16.
J Clin Oncol ; 42(15): 1821-1829, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38412399

RESUMO

PURPOSE: Hand-foot syndrome (HFS) is a dose-limiting side effect of capecitabine. Celecoxib prevents HFS by inhibiting cyclooxygenase-2 (COX-2) that is upregulated because of the underlying associated inflammation. However, systemic side effects of celecoxib have limited routine prescription. Topical diclofenac inhibits COX-2 locally with minimal risk of systemic adverse events. Therefore, we conducted this study to assess the efficacy of topical diclofenac in the prevention of capecitabine-induced HFS. METHODS: In this single-site phase III randomized double-blind trial, we enrolled patients with breast or GI cancer who were planned to receive capecitabine-based treatment. Participants were randomly assigned in a 1:1 ratio to receive topical diclofenac or placebo gel for 12 weeks or until the development of HFS, whichever occurred earlier. The primary end point was the incidence of grade 2 or 3 HFS (Common Terminology Criteria for Adverse Events version 5), which was compared between the two groups using simple logistic regression. RESULTS: In total, 264 patients were randomly assigned to receive topical diclofenac gel (n = 131) or placebo (n = 133). Grade 2 or 3 HFS was observed in 3.8% of participants in the diclofenac group compared with 15.0% in the placebo group (absolute difference, 11.2%; 95% CI, 4.3 to 18.1; P = .003). Grade 1-3 HFS was lower in the diclofenac group than in the placebo group (6.1% v 18.1%; absolute risk difference, 11.9%; 95% CI, 4.1 to 19.6). Capecitabine dose reductions because of HFS were less frequent in the diclofenac group (3.8%) than in the placebo group (13.5%; absolute risk difference, 9.7%; 95% CI, 3.0 to 16.4). CONCLUSION: Topical diclofenac prevented HFS in patients receiving capecitabine. This trial supports the use of topical diclofenac to prevent capecitabine-associated HFS.


Assuntos
Antimetabólitos Antineoplásicos , Capecitabina , Diclofenaco , Síndrome Mão-Pé , Humanos , Capecitabina/efeitos adversos , Capecitabina/administração & dosagem , Capecitabina/uso terapêutico , Método Duplo-Cego , Síndrome Mão-Pé/prevenção & controle , Síndrome Mão-Pé/etiologia , Diclofenaco/efeitos adversos , Diclofenaco/administração & dosagem , Diclofenaco/análogos & derivados , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Antimetabólitos Antineoplásicos/efeitos adversos , Antimetabólitos Antineoplásicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Administração Tópica , Adulto , Neoplasias Gastrointestinais/tratamento farmacológico , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/administração & dosagem
17.
Microbiol Spectr ; 12(3): e0252523, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38349164

RESUMO

We conducted a single-center study at a free community testing site in Baltimore City to assess the accuracy of self-performed rapid antigen tests (RATs) for COVID-19. Self-administered BinaxNOW RATs were compared with clinician-performed RATs and against a reference lab molecular testing as the gold standard. Of the 953 participants, 14.9% were positive for SARS- CoV-2 as determined by RT-PCR. The sensitivity and specificity were similar for both self- and clinician-performed RATs (sensitivity: 83.9% vs 88.2%, P = 0.40; specificity: 99.8% vs 99.6%, P = 0.6). Subgroup comparisons based on age and race yielded similar results. Notably, 5.2% (95% CI: 1.5% to 9.5%) of positive results were potentially missed due to participant misinterpretation of the self-test card. However, the false-positive rate for RATs was reassuringly comparable in accuracy to clinician-administered tests. These findings hold significant implications for physicians prescribing treatment based on patient-reported, self-administered positive test results. Our study provides robust evidence supporting the reliability and utility of patient-performed RATs, underscoring their comparable accuracy to clinician-performed RATs, and endorsing their continued use in managing COVID-19. Further studies using other rapid antigen test brands are warranted.IMPORTANCEAccurate and accessible COVID-19 testing is crucial for effective disease control and management. A recent single-center study conducted in Baltimore City examined the reliability of self-performed rapid antigen tests (RATs) for COVID-19. The study found that self-administered RATs yielded similar sensitivity and specificity to clinician-performed tests, demonstrating their comparable accuracy. These findings hold significant implications for physicians relying on patient-reported positive test results for treatment decisions. The study provides robust evidence supporting the reliability and utility of patient-performed RATs, endorsing their continued use in managing COVID-19. Furthermore, the study highlights the need for further research using different rapid antigen test brands to enhance generalizability. Ensuring affordable and widespread access to self-tests is crucial, particularly in preparation for future respiratory virus seasons and potential waves of reinfection of SARS-CoV-2 variants such as the Omicron variant.


Assuntos
COVID-19 , Humanos , COVID-19/diagnóstico , Teste para COVID-19 , Reprodutibilidade dos Testes , SARS-CoV-2
18.
J Cancer Res Ther ; 19(Suppl 2): S499-S507, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38384011

RESUMO

ABSTRACTS: Gallbladder cancer (GBC) is one of the quiet prevalent and aggressive biliary tract malignant neoplasms distinguished by significant cellular heterogeneity, metastatic activity, and a poor prognosis, with varied frequency worldwide. Most cases are detected incidentally while routine screening imaging or pathological investigation of cholecystectomy tissues and usually present with advanced disease. The surgical resection is usually done in the initial clinical stage having limited spread. Despite the surgical therapy, the death rate is significant. Furthermore, the molecular mechanisms affecting the clinical course of inflammatory gallbladder to carcinogenesis remain poorly understood. There is an impending need for developing diagnostic biomarkers and targeted approaches for GBC. The newer molecular platform, such as next-generation sequencing (NGS), such as RNA-sequencing (RNAseq), single-cell sequencing, and microarray technology, has revolutionized the field of genomics, opened a new perspective in defining genetic and epigenetic characteristics identifying molecules as possible therapeutic targets. Therefore, in this review, we would analyze transcriptomic and epigenomics profiles of GBC using already published high-throughput sequencing-based studies published between 2010 and 2023. The review would also analyze the possible impact of the technological advancement on the patient management strategy and overall survival. This may also help identify target genes and pathways linked to GBC, which may help establish molecular biomarkers, for early GBC diagnosis, personalized therapy, and management.


Assuntos
Neoplasias da Vesícula Biliar , Humanos , Neoplasias da Vesícula Biliar/diagnóstico , Neoplasias da Vesícula Biliar/genética , Neoplasias da Vesícula Biliar/patologia , Epigenômica , Colecistectomia , Perfilação da Expressão Gênica , Biomarcadores
19.
Microbiol Spectr ; 11(4): e0089223, 2023 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-37439683

RESUMO

Candida auris is a pathogen of urgent threat level as marked by the CDC. The formation of biofilms is an essential property of this fungus to establish infection and escape drug treatment. However, our understanding of pathogenesis through biofilm is hampered by heterogeneity in C. auris biofilms observed in different studies. It is imperative to replicate in vivo conditions for studying C. auris biofilm formation in vitro. Different methods are standardized, but the surface used to form biofilms lacks consistency as well as the architecture of a typical biofilm. Here, we report an in vitro technique to grow C. auris biofilms on gelatin-coated coverslips. Interestingly, C. auris cells grown on gelatin-coated coverslips either on modified synthetic sweat media or RPMI 1640 resulted in similar multilayer biofilm formation with extracellular polymeric substances (EPS). This method is also consistent with the biofilm formation of other Candida species, such as Candida glabrata and Candida albicans. Biofilms of C. glabrata developed through this method show pseudohyphae and EPS. This method can be used to understand the molecular basis of biofilm formation, associated pathogenesis, and drug tolerance. The technique is cost-effective and would thus serve in rightful screening and repurposing drug libraries for designing new therapeutics against the less-studied high-alarm pathogen C. auris. IMPORTANCE Heterogeneity is seen when multidrug-resistant C. auris biofilm is cultured using different reported methods. Biofilm formed on the gelatin surface mimics the condition of a host environment that has multilayers and EPS. This method has feasibility for drug screening and analyzing biofilms through three-dimensional (3D) reconstruction. This in vitro biofilm formation technique is also exploited to study the formation of biofilm of other Candida species. The biofilms of C. glabrata and C. albicans can also be correctly mimicked using gelatin in the biofilm-forming environment. Thus, the novel in vitro method for biofilm formation reported here can be widely used to understand the mechanism of biofilm formation, related virulence properties, and drug tolerance of C. auris and other Candida species. This simple and low-cost technique is highly suitable for screening novel inhibitors and repurposed libraries and to design new therapeutics against Candida species.


Assuntos
Antifúngicos , Candida auris , Humanos , Antifúngicos/farmacologia , Gelatina/farmacologia , Candida , Candida albicans , Biofilmes , Candida glabrata
20.
J Biomol Struct Dyn ; 41(17): 8445-8461, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36264093

RESUMO

The fungus Candida auris is a pathogen of utmost concern due to its rapid emergence across the globe, acquired antifungal drug tolerance, thermotolerance, and ability to survive in hospital settings and preserved foods. Recent incidences of comorbidity of corona patients with its infection in hospital settings highlighted the importance of understanding the pathobiology and drug tolerance of this fungus on priority. The Target of rapamycin (TOR) is a central regulator of growth across eukaryotes with an illustrated role in fungal pathology. The role of the TOR signalling pathway in the growth of C. auris is yet to be described. In-silico, analysis revealed the presence of highly conserved Tor kinase, components of TORC, and key downstream components in C. auris. Rapamycin and Torin2, the specific inhibitors of Tor reduce the growth of C. auris. An inhibition of Tor leads to cell cycle arrest at the G1 phase with a defect in cytokinesis. Interestingly, with an insignificant difference in growth at 30 and 37 °C, a sharp decline in growth is seen with Torin2 at 37 °C. The heterogeneous response emphasizes the importance of physiology-based differential cellular response at different temperatures. In addition, the inhibition of Tor suppresses the biofilm formation. In silico studies through docking and simulations showed rapamycin and torin2 as specific inhibitors of C. auris Tor kinase (CauTor kinase) and hence can be exploited for a thorough understanding of the TOR signalling pathway in pathobiology and drug tolerance of C. auris. HIGHLIGHTSConservation of TOR signalling pathway in Candida aurisRapamycin and torin2 are specific inhibitors of Cau TorUnderstanding of the role of TOR signalling pathway through the use of inhibitors rapamycin and torin2.Heterogenous response of C. auris to torin2 at different physiological conditions.Communicated by Ramaswamy H. Sarma.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA