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1.
Cancer Imaging ; 24(1): 20, 2024 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-38279133

RESUMO

BACKGROUND & AIMS: The present study utilized extracted computed tomography radiomics features to classify the gross tumor volume and normal liver tissue in hepatocellular carcinoma by mainstream machine learning methods, aiming to establish an automatic classification model. METHODS: We recruited 104 pathologically confirmed hepatocellular carcinoma patients for this study. GTV and normal liver tissue samples were manually segmented into regions of interest and randomly divided into five-fold cross-validation groups. Dimensionality reduction using LASSO regression. Radiomics models were constructed via logistic regression, support vector machine (SVM), random forest, Xgboost, and Adaboost algorithms. The diagnostic efficacy, discrimination, and calibration of algorithms were verified using area under the receiver operating characteristic curve (AUC) analyses and calibration plot comparison. RESULTS: Seven screened radiomics features excelled at distinguishing the gross tumor area. The Xgboost machine learning algorithm had the best discrimination and comprehensive diagnostic performance with an AUC of 0.9975 [95% confidence interval (CI): 0.9973-0.9978] and mean MCC of 0.9369. SVM had the second best discrimination and diagnostic performance with an AUC of 0.9846 (95% CI: 0.9835- 0.9857), mean Matthews correlation coefficient (MCC)of 0.9105, and a better calibration. All other algorithms showed an excellent ability to distinguish between gross tumor area and normal liver tissue (mean AUC 0.9825, 0.9861,0.9727,0.9644 for Adaboost, random forest, logistic regression, naivem Bayes algorithm respectively). CONCLUSION: CT radiomics based on machine learning algorithms can accurately classify GTV and normal liver tissue, while the Xgboost and SVM algorithms served as the best complementary algorithms.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Teorema de Bayes , Radiômica , Carga Tumoral , Neoplasias Hepáticas/diagnóstico por imagem , Aprendizado de Máquina , Estudos Retrospectivos
2.
Nat Ecol Evol ; 8(3): 552-563, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38238436

RESUMO

The geographic expansion of Homo sapiens populations into southeastern Europe occurred by ∼47,000 years ago (∼47 ka), marked by Initial Upper Palaeolithic (IUP) technology. H. sapiens was present in western Siberia by ∼45 ka, and IUP industries indicate early entries by ∼50 ka in the Russian Altai and 46-45 ka in northern Mongolia. H. sapiens was in northeastern Asia by ∼40 ka, with a single IUP site in China dating to 43-41 ka. Here we describe an IUP assemblage from Shiyu in northern China, dating to ∼45 ka. Shiyu contains a stone tool assemblage produced by Levallois and Volumetric Blade Reduction methods, the long-distance transfer of obsidian from sources in China and the Russian Far East (800-1,000 km away), increased hunting skills denoted by the selective culling of adult equids and the recovery of tanged and hafted projectile points with evidence of impact fractures, and the presence of a worked bone tool and a shaped graphite disc. Shiyu exhibits a set of advanced cultural behaviours, and together with the recovery of a now-lost human cranial bone, the record supports an expansion of H. sapiens into eastern Asia by about 45 ka.


Assuntos
Fósseis , Crânio , Humanos , China , Europa (Continente) , Antropologia Cultural
3.
Sensors (Basel) ; 23(17)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37688065

RESUMO

This study aims to enhance conventional vibration energy harvesting systems (VEHs) by repositioning the piezoelectric patch (PZT) in the middle of a fixed-fixed elastic steel sheet instead of the root, as is commonly the case. The system is subjected to an axial simple harmonic force at one end to induce transversal vibration and deformation. To further improve power conversion, a baffle is strategically installed at the point of maximum deflection, introducing a slapping force to augment electrical energy harvesting. Employing the theory of nonlinear beams, the equation of motion for this nonlinear elastic beam is derived, and the method of multiple scales (MOMS) is used to analyze the phenomenon of parametric excitation. This study demonstrates through experiments and theoretical analysis that the second mode yields better power generation benefits than the first mode. Additionally, the voltage generation benefits of the enhanced system with the added baffle (slapping force) surpass those of traditional VEH systems. Overall, the proposed model proves feasible and holds promising potential for efficient vibration energy harvesting applications in various industrial sectors.

4.
J Bus Psychol ; : 1-26, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37359080

RESUMO

Although much is known of the observable physical tasks associated with household management and child rearing, there is scant understanding of the less visible tasks that are just as critical. Grounding our research in the extant literature, the broader lay discussion, as well as our own qualitative research, we define, conceptualize, and operationalize this construct, which we label as "invisible family load." Using a mixed method, five-study approach, we offer a comprehensive, multidimensional definition and provide a nine-item, empirically validated scale to measure its component parts-managerial, cognitive, and emotional family load. In addition, we investigate gender differences and find, as expected, that women report higher levels of each dimension. We also examine the implications of invisible family load for employee health, well-being, and job attitudes, as well as family-to-work spillover. Although we substantiated some significant negative consequences, contrary to the popular view that consequences of invisible family load are uniformly negative, our results show some potential benefits. Even after accounting for conscientiousness and neuroticism, managerial family load related to greater family-work enrichment, and cognitive family load related to greater family satisfaction and job performance. Yet, emotional family load had uniformly negative potential consequences including greater family-to-work conflict, sleep problems, family and job exhaustion, and lower life and family satisfaction. Our research sets the stage for scholars to forge a path forward to enhance understanding of this phenomenon and its implications for individuals, their families, and the organizations for which they work. Supplementary Information: The online version contains supplementary material available at 10.1007/s10869-023-09887-7.

5.
World J Clin Cases ; 11(12): 2716-2728, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37214568

RESUMO

BACKGROUND: Early identification of severe/critical coronavirus disease 2019 (COVID-19) is crucial for timely treatment and intervention. Chest computed tomography (CT) score has been shown to be a significant factor in the diagnosis and treatment of pneumonia, however, there is currently a lack of effective early warning systems for severe/critical COVID-19 based on dynamic CT evolution. AIM: To develop a severe/critical COVID-19 prediction model using a combination of imaging scores, clinical features, and biomarker levels. METHODS: This study used an improved scoring system to extract and describe the chest CT characteristics of COVID-19 patients. The study also took into consideration the general clinical indicators such as dyspnea, oxygen saturation, alternative lengthening of telomeres (ALT), and androgen suppression treatment (AST), which are commonly associated with severe/critical COVID-19 cases. The study employed lasso regression to evaluate and rank the significance of different disease characteristics. RESULTS: The results showed that blood oxygen saturation, ALT, IL-6/IL-10, combined score, ground glass opacity score, age, crazy paving mode score, qsofa, AST, and overall lung involvement score were key factors in predicting severe/critical COVID-19 cases. The study established a COVID-19 severe/critical early warning system using various machine learning algorithms, including XGBClassifier, Logistic Regression, MLPClassifier, RandomForestClassifier, and AdaBoost Classifier. The study concluded that the prediction model based on the improved CT score and machine learning algorithms is a feasible method for early detection of severe/critical COVID-19 evolution. CONCLUSION: The findings of this study suggest that a prediction model based on improved CT scores and machine learning algorithms is effective in detecting the early warning signals of severe/critical COVID-19.

6.
J Appl Psychol ; 108(7): 1157-1189, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36534411

RESUMO

Workers who are exposed to severe situations such as death, harassment, and others' suffering at work are vulnerable to symptoms of posttraumatic stress disorder (PTSD) and severe distress. This distress may extend to their intimate partners, despite their lack of firsthand experience with the traumatic stressors. Although theory and empirical research suggest that employees' traumatic distress can transmit to their partners, the magnitude of these effects and when, how, and why intimate partners develop secondary traumatic symptoms and distress are not as clear. Drawing from crossover theory as an organizing framework (Westman, 2001), our meta-analysis of 276 articles indicates that the relationship between employee PTSD/distress and spouse PTSD/distress is as strong as the relationship between employee trauma exposure and employee PTSD/distress (ρ = .26), suggesting that workers' PTSD/distress is as distressing for partners as the traumatic stressors are for workers encountering them firsthand. Our moderation tests further revealed that the trauma-exposed workers' vulnerability to traumatic stress symptoms was stronger in military than in nonmilitary settings, whereas the extent to which their symptoms crossover to their intimate partners did not vary across occupations. Mediation tests suggest that traumatic stress crossover is partially explained by the worsened quality of the couple's relationship (e.g., increased social support burden and undermining), consistent with the crossover via couple interaction explanation in crossover theory. On the other hand, there was mixed support for the mediating role of the partner's empathy, indicating further research and clarification are needed. Implications for crossover theory and practice are discussed. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Assuntos
Estresse Ocupacional , Transtornos de Estresse Pós-Traumáticos , Humanos , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Apoio Social , Ansiedade , Local de Trabalho
7.
Sensors (Basel) ; 22(18)2022 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-36146257

RESUMO

This technical note proposes a clapping vibration energy harvesting system (CVEH system) installed in a rotating system. This device includes a rotating wheel, a drive shaft that rotates the wheel, and a double elastic steel sheet fixed on the drive shaft. One of the free ends of the steel is fixed with a magnet, and the free end of the other elastic steel is fixed with a PZT patch. We also install an array of magnets on the periphery (rim) of the wheel. The rim magnets repulse the magnet on the elastic steel sheet of the transmission shaft, causing the elastic steel to oscillate periodically, and slap the piezoelectric patch installed on the other elastic steel sheet to generate electricity. In this study, the authors' previous study on the voltage output was improved, and the accurate nonlinear natural frequency of the elastic steel was obtained by the dimensional analysis method. By adjusting the rotation speed of the wheel, the precise frequency was controlled to accurately excite the energy harvesting system and obtain the best output voltage. A simple experiment was also performed to correlate with the theoretical model. The voltage and power output efficiencies of the nonlinear frequency to linear frequency excitation of the CVEH system can reach 15.7% and 33.5%, respectively. This study confirms that the clapping VEH system has practical power generation benefits, and verifies that nonlinear frequencies are more effective than linear frequencies to excite the CVEH system to generate electricity.

8.
J Occup Organ Psychol ; 95(3): 687-717, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35942085

RESUMO

During the COVID-19 pandemic, teachers in the United States, an already at-risk occupation group, experienced new work-related stressors, safety concerns, and work-life challenges, magnifying on-going retention concerns. Integrating the crisis management literature with the unfolding model of turnover, we theorize that leader actions trigger initial employee responses but also set the stage for on-going crisis response that influence changes in teachers' turnover intentions. We apply latent growth curve modelling to test our hypotheses based on a sample of 617 K-12 teachers using nine waves of data, including a baseline survey at the start of the 2020-2021 school year and eight follow-up surveys (2-week lags) through the Fall 2020 semester. In terms of overall adaptation, teachers on average, experienced an increase in work-life balance and a decrease in turnover intentions over the course of the semester. Results also suggest that district and school leadership provide unique and complementary resources, but leader behaviours that shape initial crisis responses do not similarly affect employee responses during crisis, contrary to theory. Instead, teachers' adaptive crisis response trajectories were triggered by continued resource provision over the semester; increasing provision of valued resources (i.e., continued refinement of safety practices) and improvements in work-life balance prevented turnover intentions from spiralling throughout the crisis. Crisis management theory and research should continue to incorporate temporal dynamics and identify factors that contribute to crisis response trajectories, using designs and analyses that allow for examination as crises unfold in real time.

9.
Sensors (Basel) ; 21(21)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34770669

RESUMO

This research proposes an energy harvesting system that collects the downward airflow from a helicopter or a multi-axis unmanned rotary-wing aircraft and uses this wind force to drive the magnet to rotate, generating repulsive force, which causes the double elastic steel system to slap each other and vibrate periodically in order to generate more electricity than the traditional energy harvesting system. The design concept of the vibration mechanism in this study is to allow the elastic steel carrying the magnet to slap another elastic steel carrying the piezoelectric patch to form a set of double elastic steel vibration energy harvesting (DES VEH) systems. The theoretical DES VEH mechanism of this research is composed of a pair of cantilever beams, with magnets attached to the free end of one beam, and PZT attached to the other beam. This study analyzes the single beam system first. The MOMS method is applied to analyze the frequency response of this nonlinear system theoretically, then combines the piezoelectric patch and the magneto-electric coupling device with this nonlinear elastic beam to analyze the benefits of the system's converted electrical energy. In the theoretical study of the DES VEH system, the slapping force between the two elastic beams was considered as a concentrated load on each of the beams. Furthermore, both SES and DES VEH systems are studied and correlated. Finally, the experimental data and theoretical results are compared to verify the feasibility and correctness of the theory. It is proven that this DES VEH system can not only obtain the electric energy from the traditional SES VEH system but also obtain the extra electric energy of the steel vibration subjected to the slapping force, which generates optimal power to the greatest extent.

10.
Front Cardiovasc Med ; 8: 609857, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33981731

RESUMO

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) share a target receptor with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The use of ACEIs/ARBs may cause angiotensin-converting enzyme 2 receptor upregulation, facilitating the entry of SARS-CoV-2 into host cells. There is concern that the use of ACEIs/ARBs could increase the risks of severe COVID-19 and mortality. The impact of discontinuing these drugs in patients with COVID-19 remains uncertain. We aimed to assess the association between the use of ACEIs/ARBs and the risks of mortality and severe disease in patients with COVID-19. A systematic search was performed in PubMed, EMBASE, Cochrane Library, and MedRxiv.org from December 1, 2019, to June 20, 2020. We also identified additional citations by manually searching the reference lists of eligible articles. Forty-two observational studies including 63,893 participants were included. We found that the use of ACEIs/ARBs was not significantly associated with a reduction in the relative risk of all-cause mortality [odds ratio (OR) = 0.87, 95% confidence interval (95% CI) = 0.75-1.00; I 2 = 57%, p = 0.05]. We found no significant reduction in the risk of severe disease in the ACEI subgroup (OR = 0.95, 95% CI = 0.88-1.02, I 2 = 50%, p = 0.18), the ARB subgroup (OR = 1.03, 95% CI = 0.94-1.13, I 2 = 62%, p = 0.48), or the ACEI/ARB subgroup (OR = 0.83, 95% CI = 0.65-1.08, I 2 = 67%, p = 0.16). Moreover, seven studies showed no significant difference in the duration of hospitalization between the two groups (mean difference = 0.33, 95% CI = -1.75 to 2.40, p = 0.76). In conclusion, the use of ACEIs/ARBs appears to not have a significant effect on mortality, disease severity, or duration of hospitalization in COVID-19 patients. On the basis of the findings of this meta-analysis, there is no support for the cessation of treatment with ACEIs or ARBs in patients with COVID-19.

11.
Stress Health ; 37(5): 898-913, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33773018

RESUMO

Stressors can have negative effects on well-being, but little is known about how an individual's inability to precisely forecast upcoming stress could be a risk factor for well-being. Antecedents and outcomes of two stress forecasting variables, anticipated stress level and underestimation errors in stress forecasting (operationalized by the residual change scores obtained by regressing the evening experienced stress on the morning anticipated stress), were investigated. In a daily diary study of 110 undergraduate students over a workweek, poor sleep quality and negative affect reported in the morning predicted a higher anticipated stress of the upcoming day. Poor sleep quality was found to be related to less underestimation errors (i.e., more overestimation). Mispredicting the daily stress level was found to predict greater health complaints and negative affect by the end of the day. Those high on trait resilience were found to make fewer underestimation errors on average. Worse emotional outcomes were associated with underestimation errors during stress forecasting than with overestimation errors. This study demonstrates that examining an individual's experience in forecasting upcoming stressors is an important area for future research in determining points of intervention to promote adaptive management of daily demands.


Assuntos
Emoções , Previsões , Humanos , Estresse Psicológico/epidemiologia , Estudantes
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 50(6): 821-826, 2019 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-31880112

RESUMO

OBJECTIVE: To study the impact of atypical protein kinase Cι (PKCι) isoform PKC on the pancreatic cancer cells towards the tumoricidal effect of cytokine-induced killer (CIK) cells and explore its mechanisms. METHODS: CIK cells were prepared by inducing mononuclear cells isolated from the peripheral blood of healthy people with interleukin-2 (IL-2), interferon (IFN) and CD3 mAb and subsequently co-cultured with pancreatic epithelial cell HPDE6-C7, pancreatic cancer cells MiaPaCa and PANC-1 with or without PKC inhibitor named sodium thiomalate (ATM). All cells were divided into control group, ATM group, co-culture group with CIK and co-culture group with CIK+ATM. Cell count was used to detect the growth of each group from 1 to 8 d. Flow cytometry was used to detect the death rate of the cell lines after 48 h cell culture in each group. The small hairpin RNA (shRNA) was used for PKCι knockdown and the recombinant plasmid transfection was for PKCι overexpression in pancreatic cancer cells. Western blot and real-time fluorescent quantitative PCR (qRT-PCR) were utilized to determine the expression of PKCι protein and the impact on gene expression of transforming growth factor-ß (TGF-ß), a downstream effector modulated by PKC. Different mass concentrations of TGF-ß (1, 10, 20 ng/mL) were added into the co-culture of MiaPaCa and PANC-1 with CIK. The cell death rate was detected by flow cytometry 48 h later, so as to explore the possible mechanisms of the impact of PKCι on the tumoricidal effects of CIK cells. RESULTS: ATM and CIK were shown to suppress the growth and induce apoptosis or death of pancreatic cancer cells, meanwhile, ATM can enhance the tumoricidal effect of CIK on pancreatic cancer cells. Moreover, we found that PKCι knockdown in pancreatic cancer cells can down-regulate the gene expression of TGF-ß. In return, PKCι overexpression in pancreatic cancer cells can increase the gene expression of TGF-ß. The death rate of cancer cells with 10, 20 ng/mL TGF-ß was lower compared with the control group (P < 0.05). CONCLUSIONS: PKCι knockdown in pancreatic cancer cells can not only inhibit the growth of pancreatic cancer cells, but also enhance the tumoricidal effects of CIK on cancer cells. The possible mechanism of PKCι is to affect the immune escape of tumor cells by regulating the expression of TGF-ß.


Assuntos
Células Matadoras Induzidas por Citocinas , Neoplasias Pancreáticas , Apoptose , Linhagem Celular Tumoral , Citometria de Fluxo , Humanos , Interleucina-2
13.
J Clin Nurs ; 28(23-24): 4488-4495, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31410906

RESUMO

AIMS AND OBJECTIVES: To explore whether the risk of peripheral venous catheters failure remained constant throughout catheter use in adult patients. BACKGROUND: Peripheral venous catheters, widely used in adult patients, may have a critical threshold dwell time associated with increased risk of catheter failure. DESIGN: Prospective, observational study. We have complied with the STROBE checklist of items. METHODS: This study was conducted from July-October 2018 in Hunan, China. Data on patient factors, catheter factors and catheter failure events were collected. Poisson regression was used to assess the effect of catheter dwell time on catheter failure while adjusting for other variables. RESULTS: A total of 1,477 patients were included in the analysis. There were 854 cases (57.8%) of catheter failure. The median dwell time to catheter failure was 52 hr (interquartile range: 36-73 hr). The incidence rate of catheter failure significantly increased by 1.1%/h in the first 38 hr after catheter insertion. From 39-149 hr, the incidence rate significantly decreased, and at >149 hr, there was no significant change in the incidence rate. Meanwhile, factors such as vascular quality and infused drugs showed having an impact on catheter failure events. CONCLUSIONS: The risk of catheter failure may not remain constant throughout the dwell time. The results suggest that nurses should assess the insertion site frequently in the first 38 hr. RELEVANCE TO CLINICAL PRACTICE: The significant increase in the risk of catheter failure per hour may warrant close and frequent inspection of insertion site during the first 38 hr.


Assuntos
Cateterismo Periférico/efeitos adversos , Cateteres de Demora/efeitos adversos , Falha de Equipamento/estatística & dados numéricos , Adulto , Cateterismo Periférico/enfermagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Fatores de Tempo
14.
J Virol ; 90(9): 4696-4705, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26912617

RESUMO

UNLABELLED: The NS1 protein encoded by influenza A virus antagonizes the interferon response through various mechanisms, including blocking cellular mRNA maturation by binding the cellular CPSF30 3' end processing factor and/or suppressing the activation of interferon regulatory factor 3 (IRF3). In the present study, we identified two truncated NS1 proteins that are translated from internal AUGs at positions 235 and 241 of the NS1 open reading frame. We analyzed the cellular localization and function of the N-truncated NS1 proteins encoded by two influenza A virus strains, Udorn/72/H3N2 (Ud) and Puerto Rico/8/34/H1N1 (PR8). The NS1 protein of PR8, but not Ud, inhibits the activation of IRF3, whereas the NS1 protein of Ud, but not PR8, binds CPSF30. The truncated PR8 NS1 proteins are localized in the cytoplasm, whereas the full-length PR8 NS1 protein is localized in the nucleus. The infection of cells with a PR8 virus expressing an NS1 protein containing mutations of the two in-frame AUGs results in both the absence of truncated NS1 proteins and the reduced inhibition of activation of IRF3 and beta interferon (IFN-ß) transcription. The expression of the truncated PR8 NS1 protein by itself enhances the inhibition of the activation of IRF3 and IFN-ß transcription in Ud virus-infected cells. These results demonstrate that truncated PR8 NS1 proteins contribute to the inhibition of activation of this innate immune response. In contrast, the N-truncated NS1 proteins of the Ud strain, like the full-length NS1 protein, are localized in the nucleus, and mutation of the two in-frame AUGs has no effect on the activation of IRF3 and IFN-ß transcription. IMPORTANCE: Influenza A virus causes pandemics and annual epidemics in the human population. The viral NS1 protein plays a critical role in suppressing type I interferon expression. In the present study, we identified two novel truncated NS1 proteins that are translated from the second and third in-frame AUG codons in the NS1 open reading frame. The N-terminally truncated NS1 encoded by the H1N1 PR8 strain of influenza virus that suppresses IRF3 activation is localized primarily in the cytoplasm. We demonstrate that this truncated NS1 protein by itself enhances this suppression, demonstrating that some strains of influenza A virus express truncated forms of the NS1 protein that function in the inhibition of cytoplasmic antiviral events.


Assuntos
Vírus da Influenza A/fisiologia , Fator Regulador 3 de Interferon/metabolismo , Domínios e Motivos de Interação entre Proteínas , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Animais , Linhagem Celular , Células Cultivadas , Códon de Iniciação , Modelos Animais de Doenças , Interações Hospedeiro-Patógeno , Humanos , Influenza Humana/metabolismo , Influenza Humana/virologia , Interferon beta/genética , Camundongos , Mutação , Fases de Leitura Aberta , Biossíntese de Proteínas , Transporte Proteico , Transcrição Gênica , Proteínas não Estruturais Virais/química
16.
Biores Open Access ; 3(6): 297-310, 2014 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25469315

RESUMO

Hydrogels allow control of gel composition and mechanics, and permit incorporation of cells and a wide variety of molecules from nanoparticles to micromolecules. Peptide-linked hydrogels should tune the basic polymer into a more bioactive template to influence cellular activities. In this study, we first introduced the generation of 2D poly-(sulfobetaine methacrylate [SBMA]) hydrogel surfaces. By incorporating with functional peptide RGD and vascular endothelial growth factor-mimicking peptide KLTWQELYQLKYKG (QK) peptides, endothelial cells attached to the surface well and proliferated in a short-term culturing. However, the mechanical property, which plays a crucial role directing the cellular functions and supporting the structures, decreased when peptides graft onto hydrogels. Manipulating the mechanical property was thus necessary, and the most related factor was the monomer concentration. From our results, the higher amount of SBMA caused greater stiffness in hydrogels. Following the 2D surface studies, we fabricated 3D porous hydrogels for cell scaffolds by several methods. The salt/particle leaching method showed a more reliable way than gas-foaming method to fabricate homogeneous and open-interconnected pores within the hydrogel. Using the salt/particle leaching method, we can control the pore size before leaching. Morphology of endothelial cells within scaffolds was also investigated by scanning electron microscopy, and histological analysis was conducted in vitro and in vivo to test the biocompatibility of SB hydrogel and its potential as a therapeutic reagent for ischemic tissue repair in mice.

17.
Zhonghua Yu Fang Yi Xue Za Zhi ; 45(10): 944-8, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22321599

RESUMO

OBJECTIVE: To comprehensively evaluate the effect of interventions on obesity in Chinese pupils. METHODS: A literature research was carried out in China National Knowledge Infrastructure, Wanfang Data, VIP Database for Chinese Technical Periodicals, PubMed and the Excerpts Medica Database (EMBASE) databases to collect articles published between 1979 and 2010 concerning the effect of interventions for preventing obesity in Chinese pupils. Rate difference (RD) of the rate of obesity as the evaluation indicator was selected to Meta-analyze the effect of interventions on obesity. There are total 215 articles, in which 211 articles were written in Chinese and other articles were written in English. RESULTS: 17 literatures were used for Meta-analysis by the uniform inclusion and exclusion criteria. The results showed that the RD of obesity rate for the students in the intervention group was 3% (95%CI: 1% - 5%) after the intervention. However, the RD of obesity rate for the students in the control group was -2% (95%CI: -4% - -1%) after the intervention. Results of stratified analysis for the RD of obesity rate showed that the obesity rate for the students in the intervention group were decreased significantly after the intervention of combined programs with health education, physical exercise and nutrition interventions with moderate intervention time (1 to 2 years), the RD (95%CI) of obesity rate were 5% (2% - 8%), 3% (1% - 4%), respectively. For the studies whose baseline obesity rates was insignificant difference between the intervention group and the control group, the obesity rate for the students in the intervention group was 4% (95%CI: -7% - -1%) lower than the obesity rate for the students in the control group after the intervention. CONCLUSION: Health-education-based comprehensive intervention is effective on obesity prevention in Chinese pupils; combined intervention programs with moderate intervention time (1 to 2 years) were effective in improving efficiency of obesity prevention in pupils.


Assuntos
Educação em Saúde , Obesidade/prevenção & controle , Criança , China , Humanos , Estudantes
18.
Zhonghua Liu Xing Bing Xue Za Zhi ; 32(10): 1037-42, 2011 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-22333091

RESUMO

OBJECTIVE: To evaluate the associations between polymorphisms of LEPR Gln223Arg, LEPR Pro1019Pro and the risk on obesity. METHODS: A computerized search on literature was carried out in Wanfang, CNKI, VIP databases and CBM, PubMed, EMBASE databases to collect articles published between 1979 and 2010 concerning the associations between polymorphisms of LEPR Gln223Arg and/or LEPR Pro1019Pro and risk of obesity in the Chinese population. Odds ratios (ORs) were used to assess the strength of the association, and 95% confidence intervals (CIs) to present the precision of the estimates. Meta-analysis was performed using the STATA statistical software. RESULTS: Fifteen literature were collected for Meta-analysis by the uniform inclusion and exclusion criteria. There were 1096 obese patients and 949 controls for polymorphisms of LEPR Gln223Arg in 9 papers, together with 961 obese patients and 818 controls for polymorphisms of LEPR Pro1019Pro in 8 papers. Overall, there were significant associations between decreased risk of obesity and LEPR Gln223Arg polymorphisms (-668 A→G) (G versus A, OR = 0.66, 95%CI: 0.49 - 0.89; AG and GG versus AA, OR = 0.50, 95%CI: 0.32 - 0.77; respectively). There were significant associations between increased risk of obesity and LEPR Pro1019Pro polymorphisms (-3057 G→A) (A versus G, OR = 1.61, 95%CI: 1.15 - 2.26; AG and AA versus GG, OR = 1.50, 95%CI: 1.08 - 2.08; respectively). CONCLUSION: Variant alleles at both LEPR-668 and LEPR-3057 were associated with obesity in the Chinese Han-dominated population.


Assuntos
Obesidade/genética , Receptores para Leptina/genética , Povo Asiático/genética , Frequência do Gene , Genótipo , Humanos , Razão de Chances , Polimorfismo Genético
19.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 28(2): 124-7, 2010 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-20480650

RESUMO

OBJECTIVE: After sinboneHT bone replacement (SBR) was implanted in animals, to evaluate the biocompatibility of SBR and compounded in autogenetic bone in the proportion of one to one in order to prepare for the clinical applications in the future. METHODS: Bone defects of 10 mm x l0 mm x 2 mm was made at the mandibular of rabbits, then SBR with different granule diameter and autogenetic bone was compounded in the proportion of being applied in the left defects, while autogenetic bone was implanted in the right defects and nothing was used in the right reformed defects. Animals were sacrificed at 2, 4 and 8 weeks respectively. The biologic capacity was evaluated with anatomy, X-rays studies and histology. RESULTS: SBR has better biocompatibility, which can effectively accelerate the reconstruction of bone defects and help the new bone by being compounded with autogenetic bone. It provides the appropriate scaffold or template which would allow cellular infiltration, attachment and multiplication. CONCLUSION: SBR is a kind of bone substitute material with good biocompatibility. SBR compounded with self-bone has a better regeneration function.


Assuntos
Regeneração Óssea , Mandíbula , Animais , Substitutos Ósseos , Coelhos , Procedimentos de Cirurgia Plástica
20.
Basic Clin Pharmacol Toxicol ; 103(5): 433-44, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18801030

RESUMO

The published data revealed conflicting results of the polymorphism of MDR1 exon 26 SNP C3435T on the pharmacokinetics of cyclosporine; thus, the aim was to conduct a meta-analysis of significant magnitude to investigate the influence of SNP C3435T on the pharmacokinetics of cyclosporine. A literature search was conducted to locate the relevant papers by using the PubMed electronic source from 1997 and onwards. The pharmacokinetic parameters, including AUC(0-4), AUC(0-12), AUC(0-inf), C(max), CL/F and trough concentration (C(0)), were extracted and a meta-analysis was performed by using Stata version 9.1. A total of 14 papers concerning 1036 individuals were included in the meta-analysis. The overall results showed no major influence of SNP C3435T on the pharmacokinetic parameters, including AUC(0-4), AUC(0-inf), CL/F, C(max) and C(0), although AUC(0-12) was lower in subjects with CC genotype. A subanalysis by ethnic population showed that C(0) was lower in Caucasian individuals harbouring CC genotype. In conclusion, our meta-analysis of available studies has thus far failed to demonstrate a definitive correlation between the SNP C3435T in MDR1 gene and alterations in P-glycoprotein function that can result in altered pharmacokinetics of cyclosporine, although it was indicated in this meta-analysis that the carrier of CC genotype of the SNP C3435T of MDR1 had lower cyclosporine exposure presented as AUC(0-12) than those with at least one T allele. There seems to be ethnic differences in the relationship between the SNP C3435T of MDR1 and cyclosporine pharmacokinetics.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Ciclosporina/farmacocinética , Imunossupressores/farmacocinética , Polimorfismo de Nucleotídeo Único , Subfamília B de Transportador de Cassetes de Ligação de ATP , Alelos , Área Sob a Curva , Éxons , Genes MDR , Genótipo , Humanos , População Branca/genética
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