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1.
Comput Biol Chem ; 109: 108009, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38219419

RESUMO

Many soft biclustering algorithms have been developed and applied to various biological and biomedical data analyses. However, few mutually exclusive (hard) biclustering algorithms have been proposed, which could better identify disease or molecular subtypes with survival significance based on genomic or transcriptomic data. In this study, we developed a novel mutually exclusive spectral biclustering (MESBC) algorithm based on spectral method to detect mutually exclusive biclusters. MESBC simultaneously detects relevant features (genes) and corresponding conditions (patients) subgroups and, therefore, automatically uses the signature features for each subtype to perform the clustering. Extensive simulations revealed that MESBC provided superior accuracy in detecting pre-specified biclusters compared with the non-negative matrix factorization (NMF) and Dhillon's algorithm, particularly in very noisy data. Further analysis of the algorithm on real datasets obtained from the TCGA database showed that MESBC provided more accurate (i.e., smaller p-value) overall survival prediction in patients with lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) cancers when compared to the existing, gold-standard subtypes for lung cancers (integrative clustering). Furthermore, MESBC detected several genes with significant prognostic value in both LUAD and LUSC patients. External validation on an independent, unseen GEO dataset of LUAD showed that MESBC-derived clusters based on TCGA data still exhibited clear biclustering patterns and consistent, outstanding prognostic predictability, demonstrating robust generalizability of MESBC. Therefore, MESBC could potentially be used as a risk stratification tool to optimize the treatment for the patient, improve the selection of patients for clinical trials, and contribute to the development of novel therapeutic agents.


Assuntos
Adenocarcinoma de Pulmão , Carcinoma Pulmonar de Células não Pequenas , Carcinoma de Células Escamosas , Neoplasias Pulmonares , Humanos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Perfilação da Expressão Gênica/métodos , Algoritmos , Neoplasias Pulmonares/genética
2.
Behav Sci (Basel) ; 13(4)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37102816

RESUMO

Although there are many studies discussing the effect of Internet use on political participation, the literature has rarely focused on the relationship between the use of online-network groups and the political-participation intention in contemporary China. The discussion of this relationship is significant, as it offers a new perspective on reviewing the mobilization theory of media, especially in the context of online-network groups, and potentially provides a new channel for mobilizing a wider range of people for politics once the relationship is significant. This study aims to answer the following question: Can we predict the political-participation intention of Chinese citizens through the use of online-network groups? Based on the data of the China Social Survey 2019, this study uses the hierarchical logistic-regression method. The research finds that the specific online-network groups that can predict political-participation intention are mainly concentrated in the category of emotional relationships. Among them, although most of the online-network groups are positively correlated with political-participation intention, the possibility of generating political-participation intention of those who join the relative network group is significantly lower than for those who do not. The virtual connection built by online communication technology, the social relations, and the influence of social groups on individuals can help to explain the correlation between them.

3.
Artigo em Inglês | MEDLINE | ID: mdl-36767888

RESUMO

Cost sharing and cost shifting mechanisms are of vital importance in a prospective payment system. This paper employed the difference-in-differences method to estimate the impacts of a per diem system with inverted-U-shape rates on medical costs and the length of stay based on data from a health insurance institution. The supply side cost sharing mechanism worked so that the new payment system significantly reduced medical costs by 17.59 percent while the average length of stay varied little. After further analyzing the mechanism, we found that heterogeneous effects emerged mainly due to the special rates design. The reform decreased the cases that incurred relatively high medical costs and lengths of stay. However, cost shifting existed so that physicians could be motivated to provide unnecessary services to the patients who should have been discharged before the average length of stay. Therefore, payment rates in the per diem system require a sophisticated design to constrain its distortion to medical service provision even though medical expenditures were successfully contained.


Assuntos
Custo Compartilhado de Seguro , Seguro Saúde , Humanos , Tempo de Internação , Alocação de Custos , Gastos em Saúde , China
4.
Sensors (Basel) ; 22(20)2022 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-36298433

RESUMO

The key to evaluating the health status of cable-stayed bridges lies in the accuracy of cable force measurement. When measuring the cable force using the conventional frequency method, the clearance between the bracing cable and the protective tube is typically disregarded. Moreover, due to their large size, existing vibration sensors are difficult to install into protective tubes for steel strand-type bracing cables to measure the cable force. To address the above difficulties, a type of thin rod vibration sensor only 5 mm in diameter was designed based on the high sensitivity of Fiber Bragg grating (FBG), and high-throughput data processing software for engineering calculation (EC) was self-developed. Then, the recognition principle of the thin rod vibration sensor was theoretically analyzed and a step-by-step tension test was carried out. The results demonstrated that the relative error of the cable force measured by the thin rod vibration sensor within 12.865 Hz was less than 5% and the sensitivity reached 28.7 pm/Hz, indicating its high measurement precision. Upon subsequent application of the thin rod vibration sensor to a monitoring test in the field, the relative error of the fundamental frequency between artificial and natural excitations was less than 4%. In addition, the error relative to both the theoretical frequency and the third-party sampling frequency was less than 5%, further verifying the accuracy and applicability for monitoring the cable force of bridges under natural excitation. Compared with the traditional cantilever FBG sensor, the improved sensor with supporting data processing software has the advantages of small cross-section, high reliability, and good sensitivity. The research results can provide a reference for the subsequent accurate measurement of cable force and the development of a supporting sensor data processing system.


Assuntos
Fibras Ópticas , Vibração , Reprodutibilidade dos Testes , Aço
5.
Materials (Basel) ; 14(21)2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34771969

RESUMO

The cables of high-strength carbon fiber reinforced polymer (CFRP) plates are starting to be applied to large spatial structures. However, their main anchorage systems rely on the adhesive force, which entails risks to their integrity resulting from aging of the binding agent. In this study, a friction-based wedge anchorage system was designed for CFRP plates. The working mechanism of the proposed anchorage system was explored both theoretically and experimentally. The anti-slip mechanism and condition of CFRP plates were formulated so that the equivalent frictional angle of the contact surface between a CFRP plate and wedges must not be smaller than the sum of the dip angle of the wedge external conical surface and the frictional angle between the wedges and barrel. An analysis of the stress distribution in the anchorage zone of the CFRP plate was conducted using the Tsai-Wu failure criterion, which concluded that the compressive stresses should be reduced on the section closer to the load-bearing end of the anchorage system. Furthermore, the anchorage efficiency coefficient was proposed, which depends on stress concentration coefficients, plate thickness, length of anchorage zone, dip angle of wedge external conical surface, and its frictional angle. Then, it was determined that the minimum length of an anchorage zone for the CFRP plates with various specifications should be at least 49 times larger than the CFRP thickness. A finite element analysis and static tensile tests on six specimens were carried out. The experimental results revealed that the anchorage efficiency coefficient of the optimized anchor reached 97.9%.

6.
Front Genet ; 12: 648831, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981331

RESUMO

Genome-wide association study (GWAS) has identified thousands of genetic variants associated with complex traits and diseases. Compared with analyzing a single phenotype at a time, the joint analysis of multiple phenotypes can improve statistical power by taking into account the information from phenotypes. However, most established joint algorithms ignore the different level of correlations between multiple phenotypes; instead of that, they simultaneously analyze all phenotypes in a genetic model. Thus, they may fail to capture the genetic structure of phenotypes and consequently reduce the statistical power. In this study, we develop a novel method agglomerative nesting clustering algorithm for phenotypic dimension reduction analysis (AGNEP) to jointly analyze multiple phenotypes for GWAS. First, AGNEP uses an agglomerative nesting clustering algorithm to group correlated phenotypes and then applies principal component analysis (PCA) to generate representative phenotypes for each group. Finally, multivariate analysis is employed to test associations between genetic variants and the representative phenotypes rather than all phenotypes. We perform three simulation experiments with various genetic structures and a real dataset analysis for 19 Arabidopsis phenotypes. Compared to established methods, AGNEP is more powerful in terms of statistical power, computing time, and the number of quantitative trait nucleotides (QTNs). The analysis of the Arabidopsis real dataset further illustrates the efficiency of AGNEP for detecting QTNs, which are confirmed by The Arabidopsis Information Resource gene bank.

7.
Naunyn Schmiedebergs Arch Pharmacol ; 394(5): 1045-1054, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33394135

RESUMO

23-Hydroxytormentic acid (23-HTA) is an important herbal medicine purified from immature fruits of African Rubus aceae (Rosaceae). This study was carried out to examine the protection properties and potential mechanisms of 23-HTA against cerebral ischemia/reperfusion (I/R) damage. Rats underwent middle cerebral artery occlusion/reperfusion (MCAO/R) 2/24 h. All animals were euthanized 24 h after reperfusion. Rats were injected with various concentrations of 23-HTA intraperitoneally. Evaluations of infarct volumes, neurological deficit, and brain water contents were carried out to assess the outcome of 23-HTA treatment. The results showed that 23-HTA reduced infarct volumes, brain water content, and neurological deficit in a dosage-dependent manner. 23-HTA can also significantly reduce the numbers of TUNEL-positive cells, the expression levels of Bax, caspase-3, lipid peroxidation, Sod 1, Sod 2, catalase, and pro-inflammatory cytokines TNF and IL-1ß and increase the expression levels of Bcl-2 and p-Akt. 23-HTA has a neuroprotective effect due to its anti-apoptotic, antioxidant, and anti-inflammatory effects.


Assuntos
Antioxidantes/farmacologia , Fármacos Neuroprotetores/farmacologia , Traumatismo por Reperfusão/tratamento farmacológico , Triterpenos/farmacologia , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Antioxidantes/isolamento & purificação , Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/fisiopatologia , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/complicações , Masculino , Fármacos Neuroprotetores/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Rubus/química , Triterpenos/isolamento & purificação
8.
Materials (Basel) ; 13(18)2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32917021

RESUMO

The steel-wire-carbon-fiber-reinforced plate (SCFR plate) is a relatively new strengthening technology for concrete structures. In this paper, a series of lateral impact tests on SCFR plates and conventional carbon-fiber-reinforced plates (CFR plates) were first performed, followed by tensile tests of both the SCFR plates and the CFR plates. It is found that the SCFR plates can provide the same level of tensile strength as CFR plates, whilst having evident advantages in terms of better ductility and lateral resistance. It is also found that increasing the amount of the steel wire can improve the lateral resistance of the SCFR plate. In addition, the SCFR plate shows the advantage of a reduction in lateral damage, which is commonly experienced by CFR plates during transportation, construction, and maintenance. In the second stage of the research, flexural tests of both SCFR and CFR plate-strengthened reinforced concrete (RC) beams were performed. The failure modes and crack patterns of the RC beams were investigated. Results show that the SCFR plate-strengthened beam exhibits enhanced ductility compared to that strengthened by traditional CFR plates, thereby enhancing the flexural capacity of the RC beams. On the basis of the test results, a formula is designed to predict the flexural capacity of SCFR plates; good agreement is achieved.

9.
Sci Rep ; 9(1): 18034, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792302

RESUMO

One of the most important tasks in genome-wide association analysis (GWAS) is the detection of single-nucleotide polymorphisms (SNPs) which are related to target traits. With the development of sequencing technology, traditional statistical methods are difficult to analyze the corresponding high-dimensional massive data or SNPs. Recently, machine learning methods have become more popular in high-dimensional genetic data analysis for their fast computation speed. However, most of machine learning methods have several drawbacks, such as poor generalization ability, over-fitting, unsatisfactory classification and low detection accuracy. This study proposed a two-stage algorithm based on least angle regression and random forest (TSLRF), which firstly considered the control of population structure and polygenic effects, then selected the SNPs that were potentially related to target traits by using least angle regression (LARS), furtherly analyzed this variable subset using random forest (RF) to detect quantitative trait nucleotides (QTNs) associated with target traits. The new method has more powerful detection in simulation experiments and real data analyses. The results of simulation experiments showed that, compared with the existing approaches, the new method effectively improved the detection ability of QTNs and model fitting degree, and required less calculation time. In addition, the new method significantly distinguished QTNs and other SNPs. Subsequently, the new method was applied to analyze five flowering-related traits in Arabidopsis. The results showed that, the distinction between QTNs and unrelated SNPs was more significant than the other methods. The new method detected 60 genes confirmed to be related to the target trait, which was significantly higher than the other methods, and simultaneously detected multiple gene clusters associated with the target trait.


Assuntos
Estudo de Associação Genômica Ampla/métodos , Genômica/métodos , Aprendizado de Máquina , Modelos Genéticos , Arabidopsis/genética , Genoma de Planta/genética , Modelos Lineares , Família Multigênica/genética , Polimorfismo de Nucleotídeo Único/genética , Locos de Características Quantitativas/genética
10.
Toxicol Appl Pharmacol ; 333: 1-9, 2017 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-28803990

RESUMO

Baicalin is a major flavonoid compound purified from Scutellariae radix, which has been described as an herb in the Chinese Pharmacopoeia. Previous studies have suggested baicalin possessed extensive anti-inflammatory, anti-cancer, anti-viral properties. However, up to known, there have been no reports of safety and toxicity in the rats following oral administration of baicalin. In this present study, we showed the first evidence that treatment of baicalin (400, 800 and 1600mg/kg/day) induced significantly kidney injury and fibrosis. The collagen synthesis and fibrosis-related protein expression were increased in the kidney of Sprague-Dawley (SD) rats after treatment with high doses of baicalin. We further investigated the potential molecular mechanism of baicalin-mediated renal fibrosis and revealed that baicalin activated the transforming growth factor-ß (TGF-ß)/Smad signaling pathway in a dose-dependent manner. Moreover, we also observed that baicalin induced Smad3 interaction with transcriptional coactivator p300 accompanying with increment of Smad3 acetylation. Our results may contribute to better understanding of the future pharmacological and toxicological studies of Scutellaria baicalensis Georgi and its active compounds on the human disease.


Assuntos
Flavonoides/toxicidade , Nefropatias/induzido quimicamente , Actinas/genética , Actinas/metabolismo , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Antineoplásicos/toxicidade , Antivirais/toxicidade , Fator de Crescimento do Tecido Conjuntivo/genética , Fator de Crescimento do Tecido Conjuntivo/metabolismo , Fibronectinas/genética , Fibronectinas/metabolismo , Fibrose , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/metabolismo , Nefropatias/patologia , Ratos Sprague-Dawley , Scutellaria baicalensis , Transdução de Sinais/efeitos dos fármacos , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo
11.
Artigo em Chinês | MEDLINE | ID: mdl-18720881

RESUMO

OBJECTIVE: To assess the effect of desloratadine on quality of life (QOL) in patients with seasonal allergic rhinitis. METHOD: A randomized, double-blind, placebo-controlled study was designed on fifty patients with seasonal allergic rhinitis. The patients were randomly divided into three groups: A group: taking desloratadine by mouth and taking spraying of normal sodium; B group: placebo group, taking placebo by mouth and taking spraying of normal sodium; C group: taking desloratadine by mouth and taking spraying of Nasonex. Rhinitis quality of life (RQOL) questionnaire was used to evaluate QOL of patients with seasonal allergic rhinitis. The method of taking tabella was one tablet, one time a day; the method of taking spraying was one spray each nostril, once a day. The investigation lasted for two weeks. The RQOL questionnaire was administered at the start of the treatment and after one and two weeks of treatment by the telephone follow-up investigation. RESULT: After 1 and 2 weeks of treatment, symptoms scores were significantly decreased in the A group and C group compared with the placebo group (P < 0.05). After 1 and 2 weeks of treatment by the methods of A and C, the QOL of patients with seasonal allergic rhinitis was significantly improved compared with placebo group (P < 0.05). There was no QOL improvement in the placebo group. CONCLUSION: Desloratadine could decrease symptom scores and improve QOL in patients with seasonal allergic rhinitis. The RQOL questionnaire could help doctor to effectively evaluate QOL in patients with seasonal allergic rhinitis, because of its integrity and convenience.


Assuntos
Antagonistas não Sedativos dos Receptores H1 da Histamina/uso terapêutico , Loratadina/análogos & derivados , Qualidade de Vida , Rinite Alérgica Sazonal/tratamento farmacológico , Adolescente , Adulto , Método Duplo-Cego , Feminino , Humanos , Loratadina/uso terapêutico , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
12.
Artigo em Chinês | MEDLINE | ID: mdl-15583416

RESUMO

Two wild tomato species Lycopersicon peruvianum LA111, Lycopersicon pennellii LA716 and two cultivars "Xianfeng 98-7", "Jiaonong No.1" with different salt tolerance were treated with NaCl 150 mmol/L, and to measure the inorganic ions Na(+), K(+), Ca(2+) contents and the organic compounds free proline, soluble sugar contents. The results indicated that under salt stress, the wild species accumulated much Na(+) in young leaves, while cultivated species produced and accumulated much free proline and soluble sugar in young leaves, and Na(+) was mostly distributed to old leaves. So it can be seen that there are marked differences between wild species and cultivars in producing and accumulating these solutes under salt treatment. They adapt to salt stress through different salt tolerance mechanisms.


Assuntos
Cloreto de Sódio/farmacologia , Solanum lycopersicum/metabolismo , Cálcio/análise , Carboidratos/análise , Genótipo , Solanum lycopersicum/genética , Solanum lycopersicum/crescimento & desenvolvimento , Folhas de Planta/metabolismo , Potássio/análise , Prolina/análise , Sódio/análise
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