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1.
Exp Cell Res ; 434(1): 113877, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-38072302

RESUMO

Exploration of the molecular mechanisms of mesenchymal stem cell (MSC) growth has significant clinical benefits. Long non-coding RNAs (lncRNAs) have been reported to play vital roles in the regulation of the osteogenic differentiation of MSCs. However, the mechanism by which lncRNA affects the proliferation and apoptosis of MSCs is unclear. In this study, sequencing analysis revealed that LINC00707 was significantly decreased in non-adherent human MSCs (non-AC-hMSCs) compared to adherent human MSCs. Moreover, LINC00707 overexpression promoted non-AChMSC proliferation, cell cycle progression from the G0/G1 phase to the S phase and inhibited apoptosis, whereas LINC00707 silencing had the opposite effect. Furthermore, LINC00707 interacted directly with the quaking (QKI) protein and enhanced the E3 ubiquitin-protein ligase ring finger protein 6 (RNF6)-mediated ubiquitination of the QKI protein. Additionally, the overexpression of QKI rescued the promotive effects on proliferation and inhibitory effects on apoptosis in non-AC-hMSCs induced by the ectopic expression of LINC00707. Thus, LINC00707 contributes to the proliferation and apoptosis in non-AChMSCs by regulating the ubiquitination and degradation of the QKI protein.


Assuntos
Células-Tronco Mesenquimais , RNA Longo não Codificante , Humanos , Osteogênese/genética , Proliferação de Células/genética , Apoptose/genética , Células-Tronco Mesenquimais/metabolismo , Ubiquitinação , RNA Longo não Codificante/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a RNA/metabolismo
2.
Yi Chuan ; 42(2): 153-160, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32102772

RESUMO

Mosquito-borne diseases have become an important public health issue of global concern because of their high incidence and transmission rate. As a vector for mosquito-borne diseases, studying the interaction mechanism between mosquitoes and mosquito-borne viruses will help control mosquito-borne diseases. The impaired innate immunity and immune barriers evasion caused by mosquito-borne viruses in mosquitoes pose a potential risk for the persistent infection of the virus in mosquitoes and the outbreak of mosquito-borne diseases. The RNA interference (RNAi) pathway, as a powerful antiviral defense barrier in mosquitoes, can inhibit viral replication and transmission by producing a variety of small RNAs to degrade viral RNA. In this review, we summarize the related studies on the innate immune mechanism against mosquito- borne virus infection in mosquitoes about small interfering RNA (siRNA), microRNA (miRNA), and Piwi-interacting RNA (piRNA), aiming to provide a theoretical reference for the prevention and control of mosquito-borne diseases.


Assuntos
Culicidae/virologia , Interferência de RNA , Viroses , Animais , Culicidae/imunologia , Imunidade Inata , Mosquitos Vetores/imunologia , Mosquitos Vetores/virologia , RNA Interferente Pequeno , Viroses/prevenção & controle , Viroses/transmissão
3.
BMC Bioinformatics ; 18(1): 379, 2017 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-28851273

RESUMO

BACKGROUND: Prediction of DNA-binding residue is important for understanding the protein-DNA recognition mechanism. Many computational methods have been proposed for the prediction, but most of them do not consider the relationships of evolutionary information between residues. RESULTS: In this paper, we first propose a novel residue encoding method, referred to as the Position Specific Score Matrix (PSSM) Relation Transformation (PSSM-RT), to encode residues by utilizing the relationships of evolutionary information between residues. PDNA-62 and PDNA-224 are used to evaluate PSSM-RT and two existing PSSM encoding methods by five-fold cross-validation. Performance evaluations indicate that PSSM-RT is more effective than previous methods. This validates the point that the relationship of evolutionary information between residues is indeed useful in DNA-binding residue prediction. An ensemble learning classifier (EL_PSSM-RT) is also proposed by combining ensemble learning model and PSSM-RT to better handle the imbalance between binding and non-binding residues in datasets. EL_PSSM-RT is evaluated by five-fold cross-validation using PDNA-62 and PDNA-224 as well as two independent datasets TS-72 and TS-61. Performance comparisons with existing predictors on the four datasets demonstrate that EL_PSSM-RT is the best-performing method among all the predicting methods with improvement between 0.02-0.07 for MCC, 4.18-21.47% for ST and 0.013-0.131 for AUC. Furthermore, we analyze the importance of the pair-relationships extracted by PSSM-RT and the results validates the usefulness of PSSM-RT for encoding DNA-binding residues. CONCLUSIONS: We propose a novel prediction method for the prediction of DNA-binding residue with the inclusion of relationship of evolutionary information and ensemble learning. Performance evaluation shows that the relationship of evolutionary information between residues is indeed useful in DNA-binding residue prediction and ensemble learning can be used to address the data imbalance issue between binding and non-binding residues. A web service of EL_PSSM-RT ( http://hlt.hitsz.edu.cn:8080/PSSM-RT_SVM/ ) is provided for free access to the biological research community.


Assuntos
DNA/metabolismo , Interface Usuário-Computador , Área Sob a Curva , DNA/química , Internet , Matrizes de Pontuação de Posição Específica , Curva ROC , Máquina de Vetores de Suporte
4.
Bioinformatics ; 30(11): 1587-94, 2014 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-24489368

RESUMO

MOTIVATION: In molecular biology, molecular events describe observable alterations of biomolecules, such as binding of proteins or RNA production. These events might be responsible for drug reactions or development of certain diseases. As such, biomedical event extraction, the process of automatically detecting description of molecular interactions in research articles, attracted substantial research interest recently. Event trigger identification, detecting the words describing the event types, is a crucial and prerequisite step in the pipeline process of biomedical event extraction. Taking the event types as classes, event trigger identification can be viewed as a classification task. For each word in a sentence, a trained classifier predicts whether the word corresponds to an event type and which event type based on the context features. Therefore, a well-designed feature set with a good level of discrimination and generalization is crucial for the performance of event trigger identification. RESULTS: In this article, we propose a novel framework for event trigger identification. In particular, we learn biomedical domain knowledge from a large text corpus built from Medline and embed it into word features using neural language modeling. The embedded features are then combined with the syntactic and semantic context features using the multiple kernel learning method. The combined feature set is used for training the event trigger classifier. Experimental results on the golden standard corpus show that >2.5% improvement on F-score is achieved by the proposed framework when compared with the state-of-the-art approach, demonstrating the effectiveness of the proposed framework.


Assuntos
Mineração de Dados/métodos , Inteligência Artificial , MEDLINE , Redes Neurais de Computação , Semântica
5.
ScientificWorldJournal ; 2014: 121650, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25152899

RESUMO

Natural language understanding is to specify a computational model that maps sentences to their semantic mean representation. In this paper, we propose a novel framework to train the statistical models without using expensive fully annotated data. In particular, the input of our framework is a set of sentences labeled with abstract semantic annotations. These annotations encode the underlying embedded semantic structural relations without explicit word/semantic tag alignment. The proposed framework can automatically induce derivation rules that map sentences to their semantic meaning representations. The learning framework is applied on two statistical models, the conditional random fields (CRFs) and the hidden Markov support vector machines (HM-SVMs). Our experimental results on the DARPA communicator data show that both CRFs and HM-SVMs outperform the baseline approach, previously proposed hidden vector state (HVS) model which is also trained on abstract semantic annotations. In addition, the proposed framework shows superior performance than two other baseline approaches, a hybrid framework combining HVS and HM-SVMs and discriminative training of HVS, with a relative error reduction rate of about 25% and 15% being achieved in F-measure.


Assuntos
Modelos Estatísticos , Processamento de Linguagem Natural , Algoritmos
6.
Artigo em Inglês | MEDLINE | ID: mdl-38227409

RESUMO

Radiology report generation (RRG) has gained increasing research attention because of its huge potential to mitigate medical resource shortages and aid the process of disease decision making by radiologists. Recent advancements in Radiology Report Generation (RRG) are largely driven by improving a model's capabilities in encoding single-modal feature representations, while few studies explicitly explore the cross-modal alignment between image regions and words. Radiologists typically focus first on abnormal image regions before composing the corresponding text descriptions, thus cross-modal alignment is of great importance to learn a RRG model which is aware of abnormalities in the image. Motivated by this, we propose a Class Activation Map guided Attention Network (CAMANet) which explicitly promotes cross-modal alignment by employing aggregated class activation maps to supervise cross-modal attention learning, and simultaneously enrich the discriminative information. Experimental results demonstrate that CAMANet outperforms previous SOTA methods on two commonly used RRG benchmarks.

7.
Int J Nurs Stud ; 151: 104676, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38241817

RESUMO

BACKGROUND: Central venous catheters are widely used in clinical practice, and the incidence of central venous catheter occlusion is between 25 % and 38 %. The turbulence caused by the pulsatile flushing technique is harmful to the vascular endothelium and may lead to phlebitis. The low-speed continuous infusion catheter technique is a new type of continuous infusion that ensures that the catheter is always in a keep-vein-open state by continuous low-speed flushing; hence, avoiding the problem of catheter occlusion. OBJECTIVE: To investigate the effectiveness of the low-speed continuous infusion catheter technique and the routine care of double-lumen central venous catheters. DESIGN: This was a prospective, randomized, controlled, open-label trial. SETTING: Patients were recruited from 14 medical institutions in China between February and June 2023. PARTICIPANTS: In total, 251 patients were recruited, with 125 in the intervention group and 126 in the control group. METHODS: Patients who used double-lumen central venous catheters for infusion treatment were selected, and those who met the sampling criteria were randomly divided into intervention and control groups using the random envelope method. The intervention group used the low-speed continuous infusion catheter technique to maintain catheter patency, whereas the control group used routine care with a trial period of 7 days. The primary outcome was the occlusion rate. The secondary outcomes included nursing satisfaction and complication rates of the two groups. RESULTS: After 7 days, the rate of catheter occlusion was 28.0 % (35/125, 95 % confidence interval (CI):0.203, 0.367) in the intervention group and 53.97 % (68/126, 95 % CI: 0.449-0.629) in the control group, with a statistically significant difference (χ2 = 17.488, p < 0.001); at 3 days of intervention, the rate of catheter blockage was 8.0 % (10/125, 95 % CI: 0.039-0.142) in the intervention group and 23.8 % (30/126, 0.167-0.322) in the control group, with a statistically significant difference (χ2 = 11.707, p < 0.001). Nurse satisfaction was significantly higher in the intervention group (115/125, 92.0 %, 95 % CI: 0.858-0.961) than in the control group (104/126, 82.54 %, 95 % CI: 0.748-0.887) (χ2 = 5.049, p = 0.025). There were no statistically significant complication rates in either group (p = 0.622). CONCLUSION: The low-speed continuous infusion catheter technique helps maintain catheter patency, improves nurse satisfaction, and provides a high level of safety. REGISTRATION: Chinese Clinical Trial Registry (ChiCTR2200064007, www.chictr.org.cn). The first recruitment was conducted in February. https://www.chictr.org.cn/showproj.html?proj=177311.


Assuntos
Cateterismo Venoso Central , Cateteres Venosos Centrais , Flebite , Humanos , Estudos Prospectivos , Cateterismo Venoso Central/efeitos adversos , Incidência
8.
PLoS One ; 17(4): e0266128, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35363810

RESUMO

The susceptibility of Asian tiger mosquitoes to DENV-2 in different seasons was observed in simulated field environments as a reference to design dengue fever control strategies in Guangzhou. The life table experiments of mosquitoes in four seasons were carried out in the field. The susceptibility of Ae. albopictus to dengue virus was observed in both environments in Guangzhou in summer and winter. Ae. albopictus was infected with dengue virus by oral feeding. On day 7 and 14 after infection, the viral load in the head, ovary, and midgut of the mosquito was detected using real-time fluorescent quantitative PCR. Immune-associated gene expression in infected mosquitoes was performed using quantitative real-time reverse transcriptase PCR. The hatching rate and pupation rate of Ae. albopictus larvae in different seasons differed significantly. The winter hatching rate of larvae was lower than that in summer, and the incubation time was longer than in summer. In the winter field environment, Ae. albopictus still underwent basic growth and development processes. Mosquitoes in the simulated field environment were more susceptible to DENV-2 than those in the simulated laboratory environment. In the midgut, viral RNA levels on day 7 in summer were higher than those on day 7 in winter (F = 14.459, P = 0.01); ovarian viral RNA levels on day 7 in summer were higher than those on day 7 in winter (F = 8.656, P < 0.001), but there was no significant difference in the viral load at other time points (P > 0.05). Dicer-2 mRNA expression on day 7 in winter was 4.071 times than that on day 7 in summer: the viral load and Dicer-2 expression correlated moderately. Ae. albopictus could still develop and transmit dengue virus in winter in Guangzhou. Mosquitoes under simulated field conditions were more susceptible to DENV-2 than those under simulated laboratory conditions.


Assuntos
Aedes , Vírus da Dengue , Dengue , Animais , Mudança Climática , Feminino , Mosquitos Vetores , RNA Viral , Estações do Ano
9.
Front Public Health ; 10: 1028026, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438226

RESUMO

Introduction: Since the second half of the 20th century, Aedes albopictus, a vector for more than 20 arboviruses, has spread worldwide. Aedes albopictus is the main vector of infectious diseases transmitted by Aedes mosquitoes in China, and it has caused concerns regarding public health. A comprehensive understanding of the spatial genetic structure of this vector species at a genomic level is essential for effective vector control and the prevention of vector-borne diseases. Methods: During 2016-2018, adult female Ae. albopictus mosquitoes were collected from eight different geographical locations across China. Restriction site-associated DNA sequencing (RAD-seq) was used for high-throughput identification of single nucleotide polymorphisms (SNPs) and genotyping of the Ae. albopictus population. The spatial genetic structure was analyzed and compared to those exhibited by mitochondrial cytochrome c oxidase subunit 1 (cox1) and microsatellites in the Ae. albopictus population. Results: A total of 9,103 genome-wide SNP loci in 101 specimens and 32 haplotypes of cox1 in 231 specimens were identified in the samples from eight locations in China. Principal component analysis revealed that samples from Lingshui and Zhanjiang were more genetically different than those from the other locations. The SNPs provided a better resolution and stronger signals for novel spatial population genetic structures than those from the cox1 data and a set of previously genotyped microsatellites. The fixation indexes from the SNP dataset showed shallow but significant genetic differentiation in the population. The Mantel test indicated a positive correlation between genetic distance and geographical distance. However, the asymmetric gene flow was detected among the populations, and it was higher from south to north and west to east than in the opposite directions. Conclusions: The genome-wide SNPs revealed seven gene pools and fine spatial genetic structure of the Ae. albopictus population in China. The RAD-seq approach has great potential to increase our understanding of the spatial dynamics of population spread and establishment, which will help us to design new strategies for controlling vectors and mosquito-borne diseases.


Assuntos
Aedes , Animais , Feminino , Aedes/genética , Polimorfismo de Nucleotídeo Único , Mosquitos Vetores/genética , Variação Genética , China , Estruturas Genéticas
10.
Artif Intell Med ; 120: 102160, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34629148

RESUMO

Understanding patient opinions expressed towards healthcare services in online platforms could allow healthcare professionals to respond to address patients' concerns in a timely manner. Extracting patient opinion towards various aspects of health services is closely related to aspect-based sentiment analysis (ABSA) in which we need to identify both opinion targets and target-specific opinion expressions. The lack of aspect-level annotations however makes it difficult to build such an ABSA system. This paper proposes a joint learning framework for simultaneous unsupervised aspect extraction at the sentence level and supervised sentiment classification at the document level. It achieves 98.2% sentiment classification accuracy when tested on the reviews about healthcare services collected from Yelp, outperforming several strong baselines. Moreover, our model can extract coherent aspects and can automatically infer the distribution of aspects under different polarities without requiring aspect-level annotations for model learning.


Assuntos
Idioma , Aprendizagem , Humanos
11.
PLoS One ; 15(3): e0229829, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32187227

RESUMO

BACKGROUND: Aedes albopictus is a major vector for several tropical infectious diseases. Characterization of Ae. albopictus development under natural conditions is crucial for monitoring vector population expansion, dengue virus transmission, and disease outbreak preparedness. METHODS: This study employed mosquito traits as a proxy to understanding life-table traits in mosquitoes using a semi-field study. Ae. albopictus larval and adult life-table experiments were conducted using microcosms under semi-field conditions in Guangzhou. Stage-specific development times and survivorship rates were determined and compared under semi-field conditions in different seasons from early summer (June) to winter (January), to determine the lower temperature limit for larval development and adult survivorship and reproductivity. RESULTS: The average egg- hatching rate was 60.1%, with the highest recorded in October (77.1%; mid-autumn). The larval development time was on average 13.2 days (range, 8.5-24.1 days), with the shortest time observed in September(8.7 days; early autumn) and longest in November (22.8 days). The pupation rates of Ae. albopictus larvae were on average 88.9% (range, 81.6-93.4%); they were stable from June to September but decreased from October to November. The adult emergence rates were on average 82.5% (range, 76.8-87.9%) and decreased from July to November. The median survival time of Ae. albopictus adults was on average 7.4 (range, 4.5-9.8), with the shortest time recorded in September. The average lifetime egg mass under semi-field conditions was 37.84 eggs/female. The larvae could develop into adults at temperatures as low as 12.3°C, and the adults could survive for 30.0 days at 16.3°C and still produce eggs. Overall, correlation analysis found that mean temperature and relative humidity were variables significantly affecting larval development and adult survivorship. CONCLUSION: Ae. albopictus larvae could develop and emerge and the adults could survive and produce eggs in early winter in Guangzhou. The major impact of changes in ambient temperature, relative humidity, and light intensity was on the egg hatching rates, adult survival time, and egg mass production, rather than on pupation or adult emergence rates.


Assuntos
Aedes/crescimento & desenvolvimento , Estágios do Ciclo de Vida/fisiologia , Mosquitos Vetores/crescimento & desenvolvimento , Animais , China , Estações do Ano , Temperatura
12.
Infect Dis Poverty ; 8(1): 98, 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31791409

RESUMO

BACKGROUND: Aedes albopictus is a highly invasive mosquito species and a major vector of numerous viral pathogens. Many recent dengue fever outbreaks in China have been caused solely by the vector. Mapping of the potential distribution ranges of Ae. albopictus is crucial for epidemic preparedness and the monitoring of vector populations for disease control. Climate is a key factor influencing the distribution of the species. Despite field studies indicating seasonal population variations, very little modeling work has been done to analyze how environmental conditions influence the seasonality of Ae. albopictus. The aim of the present study was to develop a model based on available observations, climatic and environmental data, and machine learning methods for the prediction of the potential seasonal ranges of Ae. albopictus in China. METHODS: We collected comprehensive up-to-date surveillance data in China, particularly records from the northern distribution margin of Ae. albopictus. All records were assigned long-term (1970-2000) climatic data averages based on the WorldClim 2.0 data set. Machine learning regression tree models were developed using a 10-fold cross-validation method to predict the potential seasonal (or monthly) distribution ranges of Ae. albopictus in China at high resolution based on environmental conditions. The models were assessed based on sensitivity, specificity, and accuracy, using area under curve (AUC). WorldClim 2.0 and climatic and environmental data were used to produce environmental conduciveness (probability) prediction surfaces. Predicted probabilities were generated based on the averages of the 10 models. RESULTS: During 1998-2017, Ae. albopictus was observed at 200 out of the 242 localities surveyed. In addition, at least 15 new Ae. albopictus occurrence sites lay outside the potential ranges that have been predicted using models previously. The average accuracy was 98.4% (97.1-99.5%), and the average AUC was 99.1% (95.6-99.9%). The predicted Ae. albopictus distribution in winter (December-February) was limited to a small subtropical-tropical area of China, and Ae. albopictus was predicted to occur in northern China only during the short summer season (usually June-September). The predicted distribution areas in summer could reach northeastern China bordering Russia and the eastern part of the Qinghai-Tibet Plateau in southwestern China. Ae. albopictus could remain active in expansive areas from central to southern China in October and November. CONCLUSIONS: Climate and environmental conditions are key factors influencing the seasonal distribution of Ae. albopictus in China. The areas predicted to potentially host Ae. albopictus seasonally in the present study could reach northeastern China and the eastern slope of the Qinghai-Tibet Plateau. Our results present new evidence and suggest the expansion of systematic vector population monitoring activities and regular re-assessment of epidemic risk potential.


Assuntos
Aedes/fisiologia , Distribuição Animal , Meio Ambiente , Mosquitos Vetores/fisiologia , Animais , China , Clima , Aprendizado de Máquina , Modelos Biológicos , Controle de Mosquitos , Estações do Ano
13.
Parasit Vectors ; 12(1): 552, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752961

RESUMO

BACKGROUND: The Asian tiger mosquito, Aedes albopictus, is one of the 100 worst invasive species in the world and the vector for several arboviruses including dengue, Zika and chikungunya viruses. Understanding the population spatial genetic structure, migration, and gene flow of vector species is critical to effectively preventing and controlling vector-borne diseases. Little is known about the population structure and genetic differentiation of native Ae. albopictus in China. The aim of this study was to examine the patterns of the spatial genetic structures of native Ae. albopictus populations, and their relationship to dengue incidence, on a large geographical scale. METHODS: During 2016-2018, adult female Ae. albopictus mosquitoes were collected by human landing catch (HLC) or human-bait sweep-net collections in 34 localities across China. Thirteen microsatellite markers were used to examine the patterns of genetic diversity, population structure, and gene flow among native Ae. albopictus populations. The correlation between population genetic indices and dengue incidence was also examined. RESULTS: A total of 153 distinct alleles were identified at the 13 microsatellite loci in the tested populations. All loci were polymorphic, with the number of distinct alleles ranging from eight to sixteen. Genetic parameters such as PIC, heterozygosity, allelic richness and fixation index (FST) revealed highly polymorphic markers, high genetic diversity, and low population genetic differentiation. In addition, Bayesian analysis of population structure showed two distinct genetic groups in southern-western and eastern-central-northern China. The Mantel test indicated a positive correlation between genetic distance and geographical distance (R2 = 0.245, P = 0.01). STRUCTURE analysis, PCoA and GLS interpolation analysis indicated that Ae. albopictus populations in China were regionally clustered. Gene flow and relatedness estimates were generally high between populations. We observed no correlation between population genetic indices of microsatellite loci in Ae. albopictus populations and dengue incidence. CONCLUSION: Strong gene flow probably assisted by human activities inhibited population differentiation and promoted genetic diversity among populations of Ae. albopictus. This may represent a potential risk of rapid spread of mosquito-borne diseases. The spatial genetic structure, coupled with the association between genetic indices and dengue incidence, may have important implications for understanding the epidemiology, prevention, and control of vector-borne diseases.


Assuntos
Aedes/classificação , Aedes/crescimento & desenvolvimento , Distribuição Animal , Variação Genética , Genótipo , Mosquitos Vetores/classificação , Mosquitos Vetores/crescimento & desenvolvimento , Animais , China , Dengue/epidemiologia , Fluxo Gênico , Genética Populacional , Incidência , Repetições de Microssatélites , Análise Espacial
15.
J Biomed Inform ; 41(2): 393-407, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18207462

RESUMO

During the last decade, biomedicine has witnessed a tremendous development. Large amounts of experimental and computational biomedical data have been generated along with new discoveries, which are accompanied by an exponential increase in the number of biomedical publications describing these discoveries. In the meantime, there has been a great interest with scientific communities in text mining tools to find knowledge such as protein-protein interactions, which is most relevant and useful for specific analysis tasks. This paper provides a outline of the various information extraction methods in biomedical domain, especially for discovery of protein-protein interactions. It surveys methodologies involved in plain texts analyzing and processing, categorizes current work in biomedical information extraction, and provides examples of these methods. Challenges in the field are also presented and possible solutions are discussed.


Assuntos
Algoritmos , Inteligência Artificial , Processamento de Linguagem Natural , Reconhecimento Automatizado de Padrão/métodos , Publicações Periódicas como Assunto , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Proteínas/metabolismo , Sítios de Ligação , Ligação Proteica
16.
Zhonghua Nei Ke Za Zhi ; 47(12): 985-7, 2008 Dec.
Artigo em Zh | MEDLINE | ID: mdl-19134299

RESUMO

OBJECTIVE: To analyze the relationship between aortic root dimension (ARD) and anterior circulation infarction (ACI) by measuring ARD of ACI patients. METHODS: The ARD of 110 ACI patients (56 men and 54 women) were measured with 2-dimensional ultrasonography during ventricular systole. 66 control subjects (32 men and 34 women) without the clinical signs of cerebral infarction or organic heart disease and cardiac insufficiency were selected after carrying out detailed case history inquiring, physical examination, CT or MRI and ultrasonic examination. RESULTS: ARD in men and women was respectively (29.80 +/- 2.35) mm and (28.88 +/- 3.06) mm in the ACI group. While it was (27.64 +/- 1.70) mm and (26.98 +/- 1.60) mm respectively in the control subjects. ARD in men and women was significantly higher in the ACI group as compared with the control subjects (P < 0.01). Logistic regression analysis indicated that the odds ratio (confidence interval) associated with ARD was 1.630 (1.205 - 2.204) in men and 1.494 (1.098 - 2.033) in women for ACI. CONCLUSIONS: There is a close relationship between ARD and ACI. ARD is an important risk factor of ACI.


Assuntos
Aorta/diagnóstico por imagem , Infarto Cerebral/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Artérias Carótidas/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ultrassonografia
17.
Artif Intell Med ; 87: 1-8, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29559249

RESUMO

OBJECTIVE: A drug-drug interaction (DDI) is a situation in which a drug affects the activity of another drug synergistically or antagonistically when being administered together. The information of DDIs is crucial for healthcare professionals to prevent adverse drug events. Although some known DDIs can be found in purposely-built databases such as DrugBank, most information is still buried in scientific publications. Therefore, automatically extracting DDIs from biomedical texts is sorely needed. METHODS AND MATERIAL: In this paper, we propose a novel position-aware deep multi-task learning approach for extracting DDIs from biomedical texts. In particular, sentences are represented as a sequence of word embeddings and position embeddings. An attention-based bidirectional long short-term memory (BiLSTM) network is used to encode each sentence. The relative position information of words with the target drugs in text is combined with the hidden states of BiLSTM to generate the position-aware attention weights. Moreover, the tasks of predicting whether or not two drugs interact with each other and further distinguishing the types of interactions are learned jointly in multi-task learning framework. RESULTS: The proposed approach has been evaluated on the DDIExtraction challenge 2013 corpus and the results show that with the position-aware attention only, our proposed approach outperforms the state-of-the-art method by 0.99% for binary DDI classification, and with both position-aware attention and multi-task learning, our approach achieves a micro F-score of 72.99% on interaction type identification, outperforming the state-of-the-art approach by 1.51%, which demonstrates the effectiveness of the proposed approach.


Assuntos
Mineração de Dados , Aprendizado Profundo , Interações Medicamentosas , Bases de Dados Factuais , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos
18.
Artif Intell Med ; 41(3): 209-22, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17702552

RESUMO

OBJECTIVE: The hidden vector state (HVS) model is an extension of the basic discrete Markov model in which context is encoded as a stack-oriented state vector. It has been applied successfully for protein-protein interactions extraction. However, the HVS model, being a statistically based approach, requires large-scale annotated corpora in order to reliably estimate model parameters. This is normally difficult to obtain in practical applications. METHODS AND MATERIALS: In this paper, we present two novel semi-supervised learning approaches, one based on classification and the other based on expectation-maximization, to train the HVS model from both annotated and un-annotated corpora. RESULTS AND CONCLUSION: Experimental results show the improved performance over the baseline system using the HVS model trained solely from the annotated corpus, which gives the support to the feasibility and efficiency of our approaches.


Assuntos
Inteligência Artificial , Bases de Dados de Proteínas , Domínios e Motivos de Interação entre Proteínas , Mapeamento de Interação de Proteínas/métodos , Proteínas/química , Animais , Análise por Conglomerados , Estudos de Viabilidade , Humanos , Cadeias de Markov , Modelos Estatísticos , Ligação Proteica , Proteínas/metabolismo , Reprodutibilidade dos Testes
19.
Comput Methods Programs Biomed ; 88(3): 283-94, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17983685

RESUMO

Traditional Chinese Medicine (TCM) has been actively researched through various approaches, including computational techniques. A review on basic elements of TCM is provided to illuminate various challenges and progresses in its study using computational methods. Information on various TCM formulations, in particular resources on databases of TCM formulations and their integration to Western medicine, are analyzed in several facets, such as TCM classifications, types of databases, and mining tools. Aspects of computational TCM diagnosis, namely inspection, auscultation, pulse analysis as well as TCM expert systems are reviewed in term of their benefits and drawbacks. Various approaches on exploring relationships among TCM components and finding genes/proteins relating to TCM symptom complex are also studied. This survey provides a summary on the advance of computational approaches for TCM and will be useful for future knowledge discovery in this area.


Assuntos
Medicina Tradicional Chinesa , Coleta de Dados , Armazenamento e Recuperação da Informação
20.
Sci Rep ; 6: 27653, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27282833

RESUMO

Protein-DNA interactions are involved in many fundamental biological processes essential for cellular function. Most of the existing computational approaches employed only the sequence context of the target residue for its prediction. In the present study, for each target residue, we applied both the spatial context and the sequence context to construct the feature space. Subsequently, Latent Semantic Analysis (LSA) was applied to remove the redundancies in the feature space. Finally, a predictor (PDNAsite) was developed through the integration of the support vector machines (SVM) classifier and ensemble learning. Results on the PDNA-62 and the PDNA-224 datasets demonstrate that features extracted from spatial context provide more information than those from sequence context and the combination of them gives more performance gain. An analysis of the number of binding sites in the spatial context of the target site indicates that the interactions between binding sites next to each other are important for protein-DNA recognition and their binding ability. The comparison between our proposed PDNAsite method and the existing methods indicate that PDNAsite outperforms most of the existing methods and is a useful tool for DNA-binding site identification. A web-server of our predictor (http://hlt.hitsz.edu.cn:8080/PDNAsite/) is made available for free public accessible to the biological research community.


Assuntos
Proteínas de Ligação a DNA/química , DNA/química , Análise de Sequência de Proteína/métodos , Software , Sítios de Ligação , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Ligação Proteica
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