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1.
Cell ; 170(6): 1149-1163.e12, 2017 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-28886383

RESUMO

The diversity of mesenchymal cell types in the lung that influence epithelial homeostasis and regeneration is poorly defined. We used genetic lineage tracing, single-cell RNA sequencing, and organoid culture approaches to show that Lgr5 and Lgr6, well-known markers of stem cells in epithelial tissues, are markers of mesenchymal cells in the adult lung. Lgr6+ cells comprise a subpopulation of smooth muscle cells surrounding airway epithelia and promote airway differentiation of epithelial progenitors via Wnt-Fgf10 cooperation. Genetic ablation of Lgr6+ cells impairs airway injury repair in vivo. Distinct Lgr5+ cells are located in alveolar compartments and are sufficient to promote alveolar differentiation of epithelial progenitors through Wnt activation. Modulating Wnt activity altered differentiation outcomes specified by mesenchymal cells. This identification of region- and lineage-specific crosstalk between epithelium and their neighboring mesenchymal partners provides new understanding of how different cell types are maintained in the adult lung.


Assuntos
Pulmão/citologia , Mesoderma/citologia , Animais , Homeostase , Pulmão/fisiologia , Camundongos , Organoides/citologia , Alvéolos Pulmonares/citologia , Receptores Acoplados a Proteínas G/análise , Análise de Sequência de RNA , Análise de Célula Única , Transcrição Gênica
2.
Nature ; 603(7902): 706-714, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35104837

RESUMO

The SARS-CoV-2 Omicron BA.1 variant emerged in 20211 and has multiple mutations in its spike protein2. Here we show that the spike protein of Omicron has a higher affinity for ACE2 compared with Delta, and a marked change in its antigenicity increases Omicron's evasion of therapeutic monoclonal and vaccine-elicited polyclonal neutralizing antibodies after two doses. mRNA vaccination as a third vaccine dose rescues and broadens neutralization. Importantly, the antiviral drugs remdesivir and molnupiravir retain efficacy against Omicron BA.1. Replication was similar for Omicron and Delta virus isolates in human nasal epithelial cultures. However, in lung cells and gut cells, Omicron demonstrated lower replication. Omicron spike protein was less efficiently cleaved compared with Delta. The differences in replication were mapped to the entry efficiency of the virus on the basis of spike-pseudotyped virus assays. The defect in entry of Omicron pseudotyped virus to specific cell types effectively correlated with higher cellular RNA expression of TMPRSS2, and deletion of TMPRSS2 affected Delta entry to a greater extent than Omicron. Furthermore, drug inhibitors targeting specific entry pathways3 demonstrated that the Omicron spike inefficiently uses the cellular protease TMPRSS2, which promotes cell entry through plasma membrane fusion, with greater dependency on cell entry through the endocytic pathway. Consistent with suboptimal S1/S2 cleavage and inability to use TMPRSS2, syncytium formation by the Omicron spike was substantially impaired compared with the Delta spike. The less efficient spike cleavage of Omicron at S1/S2 is associated with a shift in cellular tropism away from TMPRSS2-expressing cells, with implications for altered pathogenesis.


Assuntos
COVID-19/patologia , COVID-19/virologia , Fusão de Membrana , SARS-CoV-2/metabolismo , SARS-CoV-2/patogenicidade , Serina Endopeptidases/metabolismo , Internalização do Vírus , Adulto , Idoso , Idoso de 80 Anos ou mais , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , COVID-19/imunologia , Vacinas contra COVID-19/imunologia , Linhagem Celular , Membrana Celular/metabolismo , Membrana Celular/virologia , Chlorocebus aethiops , Convalescença , Feminino , Humanos , Soros Imunes/imunologia , Intestinos/patologia , Intestinos/virologia , Pulmão/patologia , Pulmão/virologia , Masculino , Pessoa de Meia-Idade , Mutação , Mucosa Nasal/patologia , Mucosa Nasal/virologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Técnicas de Cultura de Tecidos , Virulência , Replicação Viral
3.
EMBO J ; 41(8): e109365, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35285539

RESUMO

Tissue homeostasis requires lineage fidelity of stem cells. Dysregulation of cell fate specification and differentiation leads to various diseases, yet the cellular and molecular mechanisms governing these processes remain elusive. We demonstrate that YAP/TAZ activation reprograms airway secretory cells, which subsequently lose their cellular identity and acquire squamous alveolar type 1 (AT1) fate in the lung. This cell fate conversion is mediated via distinctive transitional cell states of damage-associated transient progenitors (DATPs), recently shown to emerge during injury repair in mouse and human lungs. We further describe a YAP/TAZ signaling cascade to be integral for the fate conversion of secretory cells into AT1 fate, by modulating mTORC1/ATF4-mediated amino acid metabolism in vivo. Importantly, we observed aberrant activation of the YAP/TAZ-mTORC1-ATF4 axis in the altered airway epithelium of bronchiolitis obliterans syndrome, including substantial emergence of DATPs and AT1 cells with severe pulmonary fibrosis. Genetic and pharmacologic inhibition of mTORC1 activity suppresses lineage alteration and subepithelial fibrosis driven by YAP/TAZ activation, proposing a potential therapeutic target for human fibrotic lung diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Sinalização YAP , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Aminoácidos Essenciais , Animais , Diferenciação Celular , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos
4.
Brief Bioinform ; 25(5)2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39210504

RESUMO

Microsatellite instability (MSI), a phenomenon caused by deoxyribonucleic acid (DNA) mismatch repair system deficiencies, is an important biomarker in cancer research and clinical diagnostics. MSI detection often involves next-generation sequencing data, with many studies focusing on DNA. Here, we introduce a novel approach by measuring microsatellite lengths directly from ribonucleic acid sequencing (RNA-seq) data and comparing its distribution to detect MSI. Our findings reveal distinct instability patterns between MSI-high (MSI-H) and microsatellite stable samples, indicating the efficacy of RNA-based MSI detection. Additionally, microsatellites in the 3'-untranslated regions showed the greatest predictive value for MSI detection. Notably, this efficacy extends to detecting MSI-H samples even in tumors not commonly associated with MSI. Our approach highlights the utility of RNA-seq data in MSI detection, facilitating more precise diagnostics through the integration of various biological data.


Assuntos
Regiões 3' não Traduzidas , Instabilidade de Microssatélites , Repetições de Microssatélites , Humanos , RNA-Seq/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Neoplasias/genética
5.
BMC Plant Biol ; 23(1): 48, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36683040

RESUMO

BACKGROUND: The AP2/ERF gene family is a superfamily of transcription factors that are important in the response of plants to abiotic stress and development. However, comprehensive research of the AP2/ERF genes in the Solanaceae family is lacking. RESULTS: Here, we updated the annotation of AP2/ERF genes in the genomes of eight Solanaceae species, as well as Arabidopsis thaliana and Oryza sativa. We identified 2,195 AP2/ERF genes, of which 368 (17%) were newly identified. Based on phylogenetic analyses, we observed expansion of the copy number of these genes, especially those belonging to specific Ethylene-Responsive Factor (ERF) subgroups of the Solanaceae. From the results of chromosomal location and synteny analyses, we identified that the AP2/ERF genes of the pepper (Capsicum annuum), the tomato (Solanum lycopersicum), and the potato (Solanum tuberosum) belonging to ERF subgroups form a tandem array and most of them are species-specific without orthologs in other species, which has led to differentiation of AP2/ERF gene repertory among Solanaceae. We suggest that these genes mainly emerged through recent gene duplication after the divergence of these species. Transcriptome analyses showed that the genes have a putative function in the response of the pepper and tomato to abiotic stress, especially those in ERF subgroups. CONCLUSIONS: Our findings will provide comprehensive information on AP2/ERF genes and insights into the structural, evolutionary, and functional understanding of the role of these genes in the Solanaceae.


Assuntos
Variações do Número de Cópias de DNA , Solanum tuberosum , Filogenia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Família Multigênica , Solanum tuberosum/genética , Etilenos , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
AJR Am J Roentgenol ; 221(5): 586-598, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37315015

RESUMO

BACKGROUND. Chest radiography is an essential tool for diagnosing community-acquired pneumonia (CAP), but it has an uncertain prognostic role in the care of patients with CAP. OBJECTIVE. The purpose of this study was to develop a deep learning (DL) model to predict 30-day mortality from diagnosis among patients with CAP by use of chest radiographs to validate the performance model in patients from different time periods and institutions. METHODS. In this retrospective study, a DL model was developed from data on 7105 patients from one institution from March 2013 to December 2019 (3:1:1 allocation to training, validation, and internal test sets) to predict the risk of all-cause mortality within 30 days after CAP diagnosis by use of patients' initial chest radiographs. The DL model was evaluated in a cohort of patients diagnosed with CAP during emergency department visits at the same institution from January 2020 to March 2020 (temporal test cohort [n = 947]) and in two additional cohorts from different institutions (external test cohort A [n = 467], January 2020 to December 2020; external test cohort B [n = 381], March 2019 to October 2021). AUCs were compared between the DL model and an established risk prediction tool based on the presence of confusion, blood urea nitrogen level, respiratory rate, blood pressure, and age 65 years or older (CURB-65 score). The combination of CURB-65 score and DL model was evaluated with a logistic regression model. RESULTS. The AUC for predicting 30-day mortality was significantly larger (p < .001) for the DL model than for CURB-65 score in the temporal test set (0.77 vs 0.67). The larger AUC for the DL model than for CURB-65 score was not significant (p > .05) in external test cohort A (0.80 vs 0.73) or external test cohort B (0.80 vs 0.72). In the three cohorts, the DL model, in comparison with CURB-65 score, had higher (p < .001) specificity (range, 61-69% vs 44-58%) at the sensitivity of CURB-65 score. The combination of DL model and CURB-65 score, in comparison with CURB-65 score, yielded a significant increase in AUC in the temporal test cohort (0.77, p < .001) and external test cohort B (0.80, p = .04) and a nonsignificant increase in AUC in external test cohort A (0.80, p = .16). CONCLUSION. A DL-based model consisting of initial chest radiographs was predictive of 30-day mortality among patients with CAP with improved performance over CURB-65 score. CLINICAL IMPACT. The DL-based model may guide clinical decision-making in the care of patients with CAP.

7.
Plant Biotechnol J ; 20(6): 1031-1041, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35332665

RESUMO

Genome phasing is a recently developed assembly method that separates heterozygous eukaryotic genomic regions and builds haplotype-resolved assemblies. Because differences between haplotypes are ignored in most published de novo genomes, assemblies are available as consensus genomes consisting of haplotype mixtures, thus increasing the need for genome phasing. Here, we review the operating principles and characteristics of several freely available and widely used phasing tools (TrioCanu, FALCON-Phase, and ALLHiC). An examination of downstream analyses using haplotype-resolved genome assemblies in plants indicated significant differences among haplotypes regarding chromosomal rearrangements, sequence insertions, and expression of specific alleles that contribute to the acquisition of the biological characteristics of plant species. Finally, we suggest directions to solve addressing limitations of current genome-phasing methods. This review provides insights into the current progress, limitations, and future directions of de novo genome phasing, which will enable researchers to easily access and utilize genome-phasing in studies involving highly heterozygous complex plant genomes.


Assuntos
Genoma de Planta , Genômica , Alelos , Genoma de Planta/genética , Haplótipos/genética , Plantas/genética , Análise de Sequência de DNA/métodos
8.
Ann Emerg Med ; 79(2): 132-144, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34417073

RESUMO

STUDY OBJECTIVE: We aimed to train and validate the time to on-scene return of spontaneous circulation prediction models using time-to-event analysis among out-of-hospital cardiac arrest patients. METHODS: Using a Korean population-based out-of-hospital cardiac arrest registry, we selected a total of 105,215 adults with presumed cardiac etiologies between 2013 and 2018. Patients from 2013 to 2017 and from 2018 were analyzed for training and test, respectively. We developed 4 time-to-event analyzing models (Cox proportional hazard [Cox], random survival forest, extreme gradient boosting survival, and DeepHit) and 4 classification models (logistic regression, random forest, extreme gradient boosting, and feedforward neural network). Patient characteristics and Utstein elements collected at the scene were used as predictors. Discrimination and calibration were evaluated by Harrell's C-index and integrated Brier score. RESULTS: Among the 105,215 patients (mean age 70 years and 64% men), 86,314 and 18,901 patients belonged to the training and test sets, respectively. On-scene return of spontaneous circulation was achieved in 5,240 (6.1%) patients in the former set and 1,709 (9.0%) patients in the latter. The proportion of emergency medical services (EMS) management was higher and scene time interval longer in the latter. Median time from EMS scene arrival to on-scene return of spontaneous circulation was 8 minutes for both datasets. Classification models showed similar discrimination and poor calibration power compared to survival models; Cox showed high discrimination with the best calibration (C-index [95% confidence interval]: 0.873 [0.865 to 0.882]; integrated Brier score at 30 minutes: 0.060). CONCLUSION: Incorporating time-to-event analysis could lead to improved performance in prediction models and contribute to personalized field EMS resuscitation decisions.


Assuntos
Regras de Decisão Clínica , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/fisiopatologia , Retorno da Circulação Espontânea , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Tomada de Decisão Clínica/métodos , Estudos Transversais , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Parada Cardíaca Extra-Hospitalar/terapia , Modelos de Riscos Proporcionais , Sistema de Registros , Reprodutibilidade dos Testes , Ressuscitação , Fatores de Tempo , Adulto Jovem
9.
J Korean Med Sci ; 37(18): e144, 2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35535371

RESUMO

BACKGROUND: There are limited data on the accuracy of cloud-based speech recognition (SR) open application programming interfaces (APIs) for medical terminology. This study aimed to evaluate the medical term recognition accuracy of current available cloud-based SR open APIs in Korean. METHODS: We analyzed the SR accuracy of currently available cloud-based SR open APIs using real doctor-patient conversation recordings collected from an outpatient clinic at a large tertiary medical center in Korea. For each original and SR transcription, we analyzed the accuracy rate of each cloud-based SR open API (i.e., the number of medical terms in the SR transcription per number of medical terms in the original transcription). RESULTS: A total of 112 doctor-patient conversation recordings were converted with three cloud-based SR open APIs (Naver Clova SR from Naver Corporation; Google Speech-to-Text from Alphabet Inc.; and Amazon Transcribe from Amazon), and each transcription was compared. Naver Clova SR (75.1%) showed the highest accuracy with the recognition of medical terms compared to the other open APIs (Google Speech-to-Text, 50.9%, P < 0.001; Amazon Transcribe, 57.9%, P < 0.001), and Amazon Transcribe demonstrated higher recognition accuracy compared to Google Speech-to-Text (P < 0.001). In the sub-analysis, Naver Clova SR showed the highest accuracy in all areas according to word classes, but the accuracy of words longer than five characters showed no statistical differences (Naver Clova SR, 52.6%; Google Speech-to-Text, 56.3%; Amazon Transcribe, 36.6%). CONCLUSION: Among three current cloud-based SR open APIs, Naver Clova SR which manufactured by Korean company showed highest accuracy of medical terms in Korean, compared to Google Speech-to-Text and Amazon Transcribe. Although limitations are existing in the recognition of medical terminology, there is a lot of rooms for improvement of this promising technology by combining strengths of each SR engines.


Assuntos
Percepção da Fala , Fala , Computação em Nuvem , Comunicação , Humanos , Software
10.
BMC Med Inform Decis Mak ; 21(1): 114, 2021 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-33812383

RESUMO

BACKGROUND: Artificial intelligence (AI) research is highly dependent on the nature of the data available. With the steady increase of AI applications in the medical field, the demand for quality medical data is increasing significantly. We here describe the development of a platform for providing and sharing digital pathology data to AI researchers, and highlight challenges to overcome in operating a sustainable platform in conjunction with pathologists. METHODS: Over 3000 pathological slides from five organs (liver, colon, prostate, pancreas and biliary tract, and kidney) in histologically confirmed tumor cases by pathology departments at three hospitals were selected for the dataset. After digitalizing the slides, tumor areas were annotated and overlaid onto the images by pathologists as the ground truth for AI training. To reduce the pathologists' workload, AI-assisted annotation was established in collaboration with university AI teams. RESULTS: A web-based data sharing platform was developed to share massive pathological image data in 2019. This platform includes 3100 images, and 5 pre-processing algorithms for AI researchers to easily load images into their learning models. DISCUSSION: Due to different regulations among countries for privacy protection, when releasing internationally shared learning platforms, it is considered to be most prudent to obtain consent from patients during data acquisition. CONCLUSIONS: Despite limitations encountered during platform development and model training, the present medical image sharing platform can steadily fulfill the high demand of AI developers for quality data. This study is expected to help other researchers intending to generate similar platforms that are more effective and accessible in the future.


Assuntos
Inteligência Artificial , Neoplasias , Algoritmos , Humanos , Masculino
11.
Genomics ; 112(2): 1208-1213, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31295546

RESUMO

Interpretation of noncoding disease variants, which comprise the vast majority of Genome-wide association studies (GWAS) hits, remains a momentous challenge due to haplotype structure and our limited understanding of the mechanisms and physiological contexts of noncoding elements. GWAS have identified loci underlying human diseases, but assigning the causal nucleotide changes still remain a controversial issue. Here we addressed these issues through the combination of high-density genotyping and epigenomic data using a random forest model to discover the noncoding causal variants. Focusing on autoimmune diseases, we triaged putative causal variants for atopic dermatitis and inflammatory bowel diseases. Making a filtering pipeline, we found three interesting single nucleotide polymorphisms (rs1800630, rs1799964 and rs4796793) in the upstream site of TNF and STAT3 genes, two frequent genes shared in some autoimmune diseases, and show how those variants affect on TNF and STAT3 expression levels. All data and source codes related to this manuscript are available at https://github.com/jieunjung511/Autoimmune-research.


Assuntos
Dermatite Atópica/genética , Doenças Inflamatórias Intestinais/genética , Polimorfismo de Nucleotídeo Único , Fator de Transcrição STAT3/genética , Fator de Necrose Tumoral alfa/genética , Sequências Reguladoras de Ácido Nucleico
12.
Medicina (Kaunas) ; 56(12)2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33265954

RESUMO

Background and objectives: The aim of this study is to describe the temporal change in alert override with a minimally interruptive clinical decision support (CDS) on a Next-Generation electronic medical record (EMR) and analyze factors associated with the change. Materials and Methods: The minimally interruptive CDS used in this study was implemented in the hospital in 2016, which was a part of the new next-generation EMR, Data Analytics and Research Window for Integrated kNowledge (DARWIN), which does not generate modals, 'pop-ups' but show messages as in-line information. The prescription (medication order) and alerts data from July 2016 to December 2017 were extracted. Piece-wise regression analysis and linear regression analysis was performed to determine the temporal change and factors associated with it. Results: Overall, 2,706,395 alerts and 993 doctors were included in the study. Among doctors, 37.2% were faculty (professors), 17.2% were fellows, and 45.6% trainees (interns and residents). The overall override rate was 61.9%. There was a significant change in an increasing trend at month 12 (p < 0.001). We found doctors' positions and specialties, along with the number of alerts and medication variability, were significantly associated with the change. Conclusions: In this study, we found a significant temporal change of alert override. We also found factors associated with the change, which had statistical significance.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Sistemas de Registro de Ordens Médicas , Médicos , Registros Eletrônicos de Saúde , Humanos
13.
BMC Med Inform Decis Mak ; 19(1): 132, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307440

RESUMO

BACKGROUND: This paper presents a conditional random fields (CRF) method that enables the capture of specific high-order label transition factors to improve clinical named entity recognition performance. Consecutive clinical entities in a sentence are usually separated from each other, and the textual descriptions in clinical narrative documents frequently indicate causal or posterior relationships that can be used to facilitate clinical named entity recognition. However, the CRF that is generally used for named entity recognition is a first-order model that constrains label transition dependency of adjoining labels under the Markov assumption. METHODS: Based on the first-order structure, our proposed model utilizes non-entity tokens between separated entities as an information transmission medium by applying a label induction method. The model is referred to as precursor-induced CRF because its non-entity state memorizes precursor entity information, and the model's structure allows the precursor entity information to propagate forward through the label sequence. RESULTS: We compared the proposed model with both first- and second-order CRFs in terms of their F1-scores, using two clinical named entity recognition corpora (the i2b2 2012 challenge and the Seoul National University Hospital electronic health record). The proposed model demonstrated better entity recognition performance than both the first- and second-order CRFs and was also more efficient than the higher-order model. CONCLUSION: The proposed precursor-induced CRF which uses non-entity labels as label transition information improves entity recognition F1 score by exploiting long-distance transition factors without exponentially increasing the computational time. In contrast, a conventional second-order CRF model that uses longer distance transition factors showed even worse results than the first-order model and required the longest computation time. Thus, the proposed model could offer a considerable performance improvement over current clinical named entity recognition methods based on the CRF models.


Assuntos
Sistemas de Informação em Saúde , Modelos Teóricos , Processamento de Linguagem Natural , Humanos
14.
Blood ; 128(17): 2117-2129, 2016 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-27605510

RESUMO

MicroRNAs (miRNAs) have emerged as important regulators of the immune system. However, despite this prominence, our understanding of the function of miRNAs in the early hematopoietic stages is incomplete. In this study, we found that miR-139-5p negatively regulated the proliferation of hematopoietic stem cells and progenitor cells and that downregulation of miR-139-5p expression was associated with hematopoietic malignancy, such as chronic myeloid leukemia (CML). Knockdown of miR-139-5p resulted in myeloid-biased differentiation with expansion of myeloid progenitor cells. In contrast, miR-139-5p expression inhibited the proliferation of hematopoietic progenitors and resulted in the remission of a CML-like disease that is induced by breakpoint cluster region-Abelson (BCR-ABL) transformation. We also found that Brg1 is a functional target of miR-139-5p and that Brg1 is involved in BCR-ABL-induced leukemogenesis. Thus, our results identify miR-139-5p as a key regulator of cellular proliferation during early hematopoiesis and suggest that it is a potent antileukemic molecule.


Assuntos
Carcinogênese/genética , Diferenciação Celular/genética , Proliferação de Células/genética , Células-Tronco Hematopoéticas/citologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , MicroRNAs/metabolismo , Animais , Separação Celular , Regulação para Baixo , Citometria de Fluxo , Proteínas de Fusão bcr-abl/genética , Técnicas de Silenciamento de Genes , Humanos , Immunoblotting , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase Via Transcriptase Reversa
15.
Proc Natl Acad Sci U S A ; 112(7): E718-27, 2015 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-25646472

RESUMO

Germinal center (GC) reaction is crucial in adaptive immune responses. The formation of GC is coordinated by the expression of specific genes including Blimp-1 and Bcl-6. Although gene expression is critically influenced by the status of chromatin structure, little is known about the role of chromatin remodeling factors for regulation of GC formation. Here, we show that the SWI/SNF chromatin remodeling complex is required for GC reactions. Mice lacking Srg3/mBaf155, a core component of the SWI/SNF complex, showed impaired differentiation of GC B and follicular helper T cells in response to T cell-dependent antigen challenge. The SWI/SNF complex regulates chromatin structure at the Blimp-1 locus and represses its expression by interacting cooperatively with Bcl-6 and corepressors. The defect in GC reactions in mice lacking Srg3 was due to the derepression of Blimp-1 as supported by genetic studies with Blimp-1-ablated mice. Hence, our study identifies the SWI/SNF complex as a key mediator in GC reactions by modulating Bcl-6-dependent Blimp-1 repression.


Assuntos
Proteínas Cromossômicas não Histona/fisiologia , Regulação da Expressão Gênica/fisiologia , Centro Germinativo/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/fisiologia , Animais , Diferenciação Celular , Cromatina/química , Camundongos , Camundongos Knockout , Fator 1 de Ligação ao Domínio I Regulador Positivo , Conformação Proteica
16.
BMC Med Inform Decis Mak ; 18(1): 29, 2018 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-29783980

RESUMO

BACKGROUND: Pathology reports are written in free-text form, which precludes efficient data gathering. We aimed to overcome this limitation and design an automated system for extracting biomarker profiles from accumulated pathology reports. METHODS: We designed a new data model for representing biomarker knowledge. The automated system parses immunohistochemistry reports based on a "slide paragraph" unit defined as a set of immunohistochemistry findings obtained for the same tissue slide. Pathology reports are parsed using context-free grammar for immunohistochemistry, and using a tree-like structure for surgical pathology. The performance of the approach was validated on manually annotated pathology reports of 100 randomly selected patients managed at Seoul National University Hospital. RESULTS: High F-scores were obtained for parsing biomarker name and corresponding test results (0.999 and 0.998, respectively) from the immunohistochemistry reports, compared to relatively poor performance for parsing surgical pathology findings. However, applying the proposed approach to our single-center dataset revealed information on 221 unique biomarkers, which represents a richer result than biomarker profiles obtained based on the published literature. Owing to the data representation model, the proposed approach can associate biomarker profiles extracted from an immunohistochemistry report with corresponding pathology findings listed in one or more surgical pathology reports. Term variations are resolved by normalization to corresponding preferred terms determined by expanded dictionary look-up and text similarity-based search. CONCLUSIONS: Our proposed approach for biomarker data extraction addresses key limitations regarding data representation and can handle reports prepared in the clinical setting, which often contain incomplete sentences, typographical errors, and inconsistent formatting.


Assuntos
Biomarcadores , Tomada de Decisão Clínica , Imuno-Histoquímica , Modelos Teóricos , Processamento de Linguagem Natural , Neoplasias/metabolismo , Neoplasias/patologia , Neoplasias/cirurgia , Biomarcadores/metabolismo , Humanos
17.
Dev Biol ; 420(2): 278-286, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27713058

RESUMO

The remarkable regenerative capacity of the lung suggests that stem cells could be of therapeutic importance in diverse lung diseases; however, the successful exploitation of lung stem cell biology has long been hampered by our inability to maintain and expand adult lung stem cells while retaining their multi-lineage potential in vitro. Recently, advances in our understanding of stem cell niches and the role of key signalling modulators in controlling stem cell maintenance and differentiation have fuelled the development of new in vitro three-dimensional (3D) culture technologies that sustain the stem cell-driven formation of near-physiological, self-organizing structures called organoids. Here we review basic approaches to organoid model systems and highlight recent achievements in the generation of organoids from adult stem and progenitor cells of both the murine and human lungs. We evaluate current applications in studying cellular changes in proliferation, differentiation, plasticity, and cell polarity, and cellular and molecular crosstalk of epithelial cells with stroma. Advantages and limitations of organoids for clinical use are also discussed.


Assuntos
Pulmão/crescimento & desenvolvimento , Organoides/crescimento & desenvolvimento , Células-Tronco Adultas/citologia , Animais , Descoberta de Drogas , Humanos , Pulmão/citologia , Pneumopatias/etiologia , Pneumopatias/terapia , Camundongos , Modelos Biológicos , Técnicas de Cultura de Órgãos , Organogênese , Organoides/citologia , Regeneração
18.
Eur J Immunol ; 45(1): 167-79, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25348202

RESUMO

Foxp3(+) Treg cells are crucial for maintaining T-cell homeostasis, but their role in B-cell homeostasis remains unclear. Here, we found that Foxp3 mutant scurfy mice had fewer B-lineage cells and progenitors, including common lymphoid progenitors and lymphoid-primed multipotent progenitors, but higher myeloid-lineage cell numbers in BM compared with WT littermates. Homeostasis within the HSC compartment was also compromised with apparent expansion of long- and short-term HSCs. This abnormality was due to the lack of Treg cells, but not to the Treg-cell extrinsic functions of Foxp3 or cell-autonomous defects. Among cytokines enriched in the BM of scurfy mice, IFN-γ affected only B lymphopoiesis, but GM-CSF, TNF, and IL-6 collectively promoted granulopoiesis at the expense of B lymphopoiesis. Neutralization of these three cytokines reversed the hematopoietic defects on early B-cell progenitors in scurfy mice. Treg cells ensured B lymphopoiesis by reducing the production of these cytokines by effector T cells, but not by directly affecting B lymphopoiesis. These results suggest that Treg cells occupy an important niche in the BM to protect B-lineage progenitor cells from excessive exposure to a lymphopoiesis-regulating milieu.


Assuntos
Linfócitos B/citologia , Células da Medula Óssea/citologia , Fatores de Transcrição Forkhead/imunologia , Granulócitos/citologia , Células-Tronco/citologia , Linfócitos T Reguladores/citologia , Animais , Anticorpos Neutralizantes/farmacologia , Linfócitos B/efeitos dos fármacos , Linfócitos B/imunologia , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/imunologia , Linhagem da Célula/imunologia , Proliferação de Células , Fatores de Transcrição Forkhead/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Granulócitos/efeitos dos fármacos , Granulócitos/imunologia , Homeostase/imunologia , Interferon gama/antagonistas & inibidores , Interferon gama/imunologia , Interleucina-6/antagonistas & inibidores , Interleucina-6/imunologia , Masculino , Camundongos , Camundongos Transgênicos , Cultura Primária de Células , Células-Tronco/efeitos dos fármacos , Células-Tronco/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/imunologia
19.
J Korean Med Sci ; 31(12): 1887-1896, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27822925

RESUMO

The application of appropriate rules for drug-drug interactions (DDIs) could substantially reduce the number of adverse drug events. However, current implementations of such rules in tertiary hospitals are problematic as physicians are receiving too many alerts, causing high override rates and alert fatigue. We investigated the potential impact of Korean national DDI rules in a drug utilization review program in terms of their severity coverage and the clinical efficiency of how physicians respond to them. Using lists of high-priority DDIs developed with the support of the U.S. government, we evaluated 706 contraindicated DDI pairs released in May 2015. We evaluated clinical log data from one tertiary hospital and prescription data from two other tertiary hospitals. The measured parameters were national DDI rule coverage for high-priority DDIs, alert override rate, and number of prescription pairs. The coverage rates of national DDI rules were 80% and 3.0% at the class and drug levels, respectively. The analysis of the system log data showed an overall override rate of 79.6%. Only 0.3% of all of the alerts (n = 66) were high-priority DDI rules. These showed a lower override rate of 51.5%, which was much lower than for the overall DDI rules. We also found 342 and 80 unmatched high-priority DDI pairs which were absent in national rules in inpatient orders from the other two hospitals. The national DDI rules are not complete in terms of their coverage of severe DDIs. They also lack clinical efficiency in tertiary settings, suggesting improved systematic approaches are needed.


Assuntos
Interações Medicamentosas , Erros de Medicação/legislação & jurisprudência , Prescrições de Medicamentos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/prevenção & controle , Humanos , República da Coreia , Centros de Atenção Terciária
20.
J Am Soc Nephrol ; 26(6): 1426-33, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25343954

RESUMO

Although renal hyperfiltration (RHF) or an abnormal increase in GFR has been associated with many lifestyles and clinical conditions, including diabetes, its clinical consequence is not clear. RHF is frequently considered to be the result of overestimating true GFR in subjects with muscle wasting. To evaluate the association between RHF and mortality, 43,503 adult Koreans who underwent voluntary health screening at Seoul National University Hospital between March of 1995 and May of 2006 with baseline GFR≥60 ml/min per 1.73 m(2) were followed up for mortality until December 31, 2012. GFR was estimated with the Chronic Kidney Disease Epidemiology Collaboration creatinine equation, and RHF was defined as GFR>95th percentile after adjustment for age, sex, muscle mass, and history of diabetes and/or hypertension medication. Muscle mass was measured with bioimpedance analysis at baseline. During the median follow-up of 12.4 years, 1743 deaths occurred. The odds ratio of RHF in participants with the highest quartile of muscle mass was 1.31 (95% confidence interval [95% CI], 1.11 to 1.54) compared with the lowest quartile after adjusting for confounding factors, including body mass index. The hazard ratio of all-cause mortality for RHF was 1.37 (95% CI, 1.11 to 1.70) by Cox proportional hazards model with adjustment for known risk factors, including smoking. These data suggest RHF may be associated with increased all-cause mortality in an apparently healthy population. The possibility of RHF as a novel marker of all-cause mortality should be confirmed.


Assuntos
Causas de Morte , Glomérulos Renais/fisiopatologia , Estilo de Vida , Insuficiência Renal Crônica/mortalidade , Adulto , Fatores Etários , Idoso , Antropometria , Índice de Massa Corporal , Comorbidade , Feminino , Taxa de Filtração Glomerular , Humanos , Incidência , Glomérulos Renais/metabolismo , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Razão de Chances , Modelos de Riscos Proporcionais , Insuficiência Renal Crônica/fisiopatologia , República da Coreia , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Fatores Sexuais , Fumar/epidemiologia , Análise de Sobrevida
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