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1.
Histol Histopathol ; 36(8): 833-844, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33829420

RESUMO

Cells cultured as monolayers proliferate well, but do not sustain their differentiation characteristics. Previous studies have investigated the interactions between cells and growth factors or cytokines by establishing either in vivo or in vitro three-dimensional (3D) cultures. Using porcine uterine epithelial cells and endometrial cells, the current study was designed to develop a 3D uterine culture system and investigate the response to hormone treatment. Formation of the 3D uterine model was similar to that of uterus from the group supplemented with calcium and magnesium, and the addition of these ions altered the spectrum of basement membrane degrading enzyme expression and activity. In particular, the epithelial cell junctions in the 3D model most closely resembled those of an actual uterus when the medium was supplemented with calcium and magnesium; the intercellular basement membrane structure was also tall under these conditions. The study confirmed that Casp-3 expression was lowest in the P4 (progesterone) treatment group, and this hormone was the most potent stimulus for formation of the endometrial cell layer. Therefore, the addition of calcium and magnesium plays an important role in the formation of a 3D uterine model, and the addition of P4 hormone mimics uterine thickening by stimulating growth of the epithelial cell layer.


Assuntos
Endométrio/citologia , Endométrio/patologia , Estradiol/farmacologia , Progesterona/farmacologia , Células Estromais/citologia , Animais , Técnicas de Cocultura , Endométrio/metabolismo , Feminino , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Suínos , Inibidor Tecidual de Metaloproteinase-2/metabolismo , Inibidor Tecidual de Metaloproteinase-3/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
2.
Nano Lett ; 21(1): 107-113, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33296220

RESUMO

Traditionally, the manipulation of contact mechanisms has been adopted as the primary strategy to tailor the friction properties of surfaces. On the contrary, the detaching process involving the local deformation and failure at the interface has been considered relatively less important. Here, we present a new approach toward the friction control of amorphous carbon through the plasticity and resultant transition of deformation mode on nanopatterned surfaces. Depending on the topography of the nanopatterns, the mechanical responses of the surfaces alter from elastic fracture to plastic flow, through which the friction coefficient changes by a factor of 5 without manipulation of the intrinsic structure of the material.

3.
Nano Lett ; 19(12): 8488-8494, 2019 12 11.
Artigo em Inglês | MEDLINE | ID: mdl-31726005

RESUMO

Synthesizing ceramic materials with a significant amount of deformability is one of the most important engineering pursuits. In this study, we demonstrate the emergence of metal-like plasticity through the crystallinity control in the monolithic zirconia with the vertically aligned honeycomb-like periodic nanopore structures fabricated using the anodizing technique. The crystalline orders of the nanoporous zirconia films vary between monoclinic, tetragonal, and amorphous phases after the heat treatment and/or proton irradiation, whereas the vertical pore structures are maintained. The micropillar compression tests on those samples reveal a large amount of plasticity, more than 20% of total stains, in the as-anodized and proton-irradiated samples, both of which contain the amorphous phase. In contrast, the fully crystallized zirconia that resulted from annealing at 500 °C shows the brittle failure, the typical characteristic of conventional ceramic foams. These results offer a new opportunity for the nanoporous ceramic materials to be used in various applications, benefited from the tunable structural stability.

4.
ACS Appl Mater Interfaces ; 10(49): 43122-43130, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30444109

RESUMO

Any transition toward an era of flexible electronics will have to overcome the mechanical limitations of materials. Specifically, the attainment of both strength and flexibility, which are generally mutually exclusive, is required including glass-like wear resistance, plastic-like compliance, and a high level of strain. Here, we fabricate a urethane-methacrylate-siloxane hybrid (UMSH) material. It is found that UMSH, with molecule-level hybridization of urethane linkage and methacrylate-siloxane conetworks, demonstrates ceramic-like high strength (574 MPa), yet polymer-like low modulus (8.42 GPa), and even high strain (6.3%) at fracture with excellent optical transparency. This combination of high strength, flexibility, and optical transparency indicates that this is a suitable material for glass substitution and can be used as a transparent flexible cover window for foldable display.

5.
Small ; 14(44): e1802239, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30286275

RESUMO

Density-strength tradeoff appears to be an inherent limitation for most materials and therefore design of cell topology that mitigates strength decrease with density reduction has been a long-lasting engineering pursue for porous materials. Continuum-mechanics-based analyses of mechanical responses of conventional porous materials with bending-dominated structures often give the density-strength scaling law following the power-law relationship with an exponent of 1.5 or higher, which consequentially determines the upper bound of the specific strength for a material to reach. In this work, a new design criterion capable of significantly abating strength degradation in lightweight materials is presented, by successfully combining the size-induced strengthening effect in nanomaterials with the architectural design of cellular porous materials. Hollow-tube-based 3D ceramic nanoarchitectures satisfying such criterion are fabricated in large area using proximity field nano-patterning and atomic layer deposition. Experimental data from micropillar compression confirm that the strengths of these nanoarchitectural materials scale with relative densities with a power-law exponent of 0.93, a hardly observable value in conventional bending-dominated porous materials. This discovery of a new density-strength scaling law in nanoarchitectured materials will contribute to creating new lightweight structural materials attaining unprecedented specific strengths overcoming the conventional limit.


Assuntos
Cerâmica/química , Nanoestruturas/química , Força Compressiva , Teste de Materiais , Porosidade , Estresse Mecânico
6.
PLoS One ; 12(4): e0176222, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28437484

RESUMO

The Electrocardiogram Vigilance with Electronic data Warehouse II (ECG-ViEW II) is a large, single-center database comprising numeric parameter data of the surface electrocardiograms of all patients who underwent testing from 1 June 1994 to 31 July 2013. The electrocardiographic data include the test date, clinical department, RR interval, PR interval, QRS duration, QT interval, QTc interval, P axis, QRS axis, and T axis. These data are connected with patient age, sex, ethnicity, comorbidities, age-adjusted Charlson comorbidity index, prescribed drugs, and electrolyte levels. This longitudinal observational database contains 979,273 electrocardiograms from 461,178 patients over a 19-year study period. This database can provide an opportunity to study electrocardiographic changes caused by medications, disease, or other demographic variables. ECG-ViEW II is freely available at http://www.ecgview.org.


Assuntos
Bases de Dados Factuais , Eletrocardiografia , Sistema de Condução Cardíaco/fisiologia , Frequência Cardíaca/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Valores de Referência , Adulto Jovem
7.
Adv Mater ; 29(19)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28295731

RESUMO

A flexible hard coating for foldable displays is realized by the highly cross-linked siloxane hybrid using structure-property relationships in organic-inorganic hybridization. Glass-like wear resistance, plastic-like flexibility, and highly elastic resilience are demonstrated together with outstanding optical transparency. It provides a framework for the application of siloxane hybrids in protective hard coatings with high scratch resistance and flexibility for foldable displays.

8.
Int J Med Inform ; 101: 100-107, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28347440

RESUMO

OBJECTIVE: The adoption rate of electronic health record (EHR) systems in South Korea has continuously increased. However, in contrast to the situation in the United States (US), where there has been a national effort to improve and standardize EHR interoperability, no consensus has been established in South Korea. The goal of this study was to determine the current status of EHR adoption in South Korean hospitals compared to that in the US. METHODS: All general and tertiary teaching hospitals in South Korea were surveyed regarding their EHR status in 2015 with the same questionnaire as used previously. The survey form estimated the level of adoption of EHR systems according to 24 core functions in four categories (clinical documentation, result view, computerized provider order entry, and decision supports). The adoption level was classified into comprehensive and basic EHR systems according to their functionalities. RESULTS: EHRs and computerized physician order entry systems were used in 58.1% and 86.0% of South Korean hospitals, respectively. Decision support systems and problem list documentation were the functions most frequently missing from comprehensive and basic EHR systems. The main barriers cited to adoption of EHR systems were the cost of purchasing (48%) and the ongoing cost of maintenance (11%). DISCUSSION: The EHR adoption rate in Korean hospitals (37.2%) was higher than that in US hospitals in 2010 (15.1%), but this trend was reversed in 2015 (58.1% vs. 75.2%). The evidence suggests that these trends were influenced by the level of financial and political support provided to US hospitals after the HITECH Act was passed in 2009. CONCLUSIONS: The EHR adoption rate in Korea has increased, albeit more slowly than in the US. It is logical to suggest that increased funding and support tied to the HITECH Act in the US partly explains the difference in the adoption rates of EHRs in both countries.


Assuntos
Registros Eletrônicos de Saúde/estatística & dados numéricos , Hospitais Gerais/estatística & dados numéricos , Hospitais de Ensino/estatística & dados numéricos , Administração da Prática Médica , Humanos , República da Coreia
9.
Mol Med Rep ; 14(4): 3697-703, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27600198

RESUMO

Tight junctions are the outermost structures of intercellular junctions and are classified as transmembrane proteins. These factors form selective permeability barriers between cells, act as paracellular transporters and regulate structural and functional polarity of cells. Although tight junctions have been previously studied, comparison of the transcriptional­translational levels of these molecules in canine organs remains to be investigated. In the present study, organ­specific expression of the tight junction proteins, claudin, occludin, junction adhesion molecule A and zona occludens 1 was examined in the canine duodenum, lung, liver and kidney. Results of immunohistochemistry analysis demonstrated that the tight junctions were localized in intestinal villi and glands of the duodenum, bronchiolar epithelia and alveolar walls of the lung, endometrium and myometrium of the hepatocytes, and the distal tubules and glomeruli of the kidney. These results suggest that tight junctions are differently expressed in organs, and therefore may be involved in organ­specific functions to maintain physiological homeostasis.


Assuntos
Claudinas/análise , Cães/genética , Molécula A de Adesão Juncional/análise , Ocludina/análise , Proteína da Zônula de Oclusão-1/genética , Animais , Claudinas/genética , Duodeno/metabolismo , Duodeno/ultraestrutura , Feminino , Expressão Gênica , Molécula A de Adesão Juncional/genética , Rim/metabolismo , Rim/ultraestrutura , Fígado/metabolismo , Fígado/ultraestrutura , Pulmão/metabolismo , Pulmão/ultraestrutura , Ocludina/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Proteína da Zônula de Oclusão-1/análise
10.
PLoS One ; 11(7): e0158130, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27386858

RESUMO

BACKGROUND AND OBJECTIVE: Patients who should be treated with both warfarin and a statin are frequently seen in vascular clinics. The risk for bleeding and potential drug interactions should be considered when prescribing both medications together. This study aimed to compare the risk for gastrointestinal bleeding among different statin exposures with concomitant administration of warfarin. MATERIALS AND METHODS: This is a single-hospital retrospective cohort study. We included patients who were concomitantly exposed to one of four statins (pravastatin, simvastatin, atorvastatin, and rosuvastatin) and warfarin for up to 2 years (730 days). The observation period ended when a gastrointestinal bleeding event occurred or the observation was censored. Within-class comparisons were used, and 1:1 matching using a propensity score was performed for comparisons between each statin and all of the other statins. Kaplan-Meier analyses with log-rank tests and Cox proportional hazard regression analyses were conducted to determine associations with the risk of gastrointestinal bleeding. RESULTS: Data were analyzed for 1,686 patients who were concomitantly administered a statin and warfarin. Log-rank tests for the gastrointestinal bleeding-free survival rate showed that the risk for gastrointestinal bleeding was significantly lower in the pravastatin group (p = 0.0499) and higher in the rosuvastatin group (p = 0.009). In the Cox proportional hazard regression analysis, the hazard ratio of 5.394 for gastrointestinal bleeding based on statin exposure in the rosuvastatin group was significant (95% confidence interval, 1.168-24.916). CONCLUSIONS: There was a relatively high risk of gastrointestinal bleeding with rosuvastatin when administered concomitantly with warfarin.


Assuntos
Hemorragia Gastrointestinal/induzido quimicamente , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Varfarina/administração & dosagem , Idoso , Anticoagulantes/administração & dosagem , Atorvastatina/administração & dosagem , Fibrilação Atrial/tratamento farmacológico , Interações Medicamentosas , Registros Eletrônicos de Saúde , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Pravastatina/administração & dosagem , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Rosuvastatina Cálcica/administração & dosagem , Sinvastatina/administração & dosagem , Software , Centros de Atenção Terciária
11.
Healthc Inform Res ; 22(1): 54-8, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26893951

RESUMO

OBJECTIVES: A distributed research network (DRN) has the advantages of improved statistical power, and it can reveal more significant relationships by increasing sample size. However, differences in data structure constitute a major barrier to integrating data among DRN partners. We describe our experience converting Electronic Health Records (EHR) to the Observational Health Data Sciences and Informatics (OHDSI) Common Data Model (CDM). METHODS: We transformed the EHR of a hospital into Observational Medical Outcomes Partnership (OMOP) CDM ver. 4.0 used in OHDSI. All EHR codes were mapped and converted into the standard vocabulary of the CDM. All data required by the CDM were extracted, transformed, and loaded (ETL) into the CDM structure. To validate and improve the quality of the transformed dataset, the open-source data characterization program ACHILLES was run on the converted data. RESULTS: Patient, drug, condition, procedure, and visit data from 2.07 million patients who visited the subject hospital from July 1994 to November 2014 were transformed into the CDM. The transformed dataset was named the AUSOM. ACHILLES revealed 36 errors and 13 warnings in the AUSOM. We reviewed and corrected 28 errors. The summarized results of the AUSOM processed with ACHILLES are available at http://ami.ajou.ac.kr:8080/. CONCLUSIONS: We successfully converted our EHRs to a CDM and were able to participate as a data partner in an international DRN. Converting local records in this manner will provide various opportunities for researchers and data holders.

12.
Pharmacoepidemiol Drug Saf ; 25(3): 307-16, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26527579

RESUMO

PURPOSE: Distributed research networks (DRNs) afford statistical power by integrating observational data from multiple partners for retrospective studies. However, laboratory test results across care sites are derived using different assays from varying patient populations, making it difficult to simply combine data for analysis. Additionally, existing normalization methods are not suitable for retrospective studies. We normalized laboratory results from different data sources by adjusting for heterogeneous clinico-epidemiologic characteristics of the data and called this the subgroup-adjusted normalization (SAN) method. METHODS: Subgroup-adjusted normalization renders the means and standard deviations of distributions identical under population structure-adjusted conditions. To evaluate its performance, we compared SAN with existing methods for simulated and real datasets consisting of blood urea nitrogen, serum creatinine, hematocrit, hemoglobin, serum potassium, and total bilirubin. Various clinico-epidemiologic characteristics can be applied together in SAN. For simplicity of comparison, age and gender were used to adjust population heterogeneity in this study. RESULTS: In simulations, SAN had the lowest standardized difference in means (SDM) and Kolmogorov-Smirnov values for all tests (p < 0.05). In a real dataset, SAN had the lowest SDM and Kolmogorov-Smirnov values for blood urea nitrogen, hematocrit, hemoglobin, and serum potassium, and the lowest SDM for serum creatinine (p < 0.05). CONCLUSION: Subgroup-adjusted normalization performed better than normalization using other methods. The SAN method is applicable in a DRN environment and should facilitate analysis of data integrated across DRN partners for retrospective observational studies.


Assuntos
Sistemas de Informação em Laboratório Clínico/normas , Pesquisa Comparativa da Efetividade/métodos , Simulação por Computador , Bases de Dados Factuais/normas , Registros Eletrônicos de Saúde/normas , Farmacoepidemiologia/métodos , Sistemas de Informação em Laboratório Clínico/tendências , Bases de Dados Factuais/tendências , Registros Eletrônicos de Saúde/tendências , Laboratórios Hospitalares/normas , República da Coreia , Estudos Retrospectivos , Software
13.
Healthc Inform Res ; 20(4): 280-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25405064

RESUMO

OBJECTIVES: To reveal differences in drug-drug interaction (DDI) alerts and the reasons for alert overrides between admitting departments. METHODS: A retrospective observational study was performed using longitudinal Electronic Health Record (EHR) data and information from an alert and logging system. Adult patients hospitalized in the emergency department (ED) and general ward (GW) during a 46-month period were included. For qualitative analyses, we manually reviewed all reasons for alert overrides, which were recorded as free text in the EHRs. RESULTS: Among 14,780,519 prescriptions, 51,864 had alerts for DDIs (0.35%; 1.32% in the ED and 0.23% in the GW). The alert override rate was higher in the ED (94.0%) than in the GW (57.0%) (p < 0.001). In an analysis of the study population, including ED and GW patients, 'clinically irrelevant alert' (52.0%) was the most common reason for override, followed by 'benefit assessed to be greater than the risk' (31.1%) and 'others' (17.3%). The frequency of alert overrides was highest for anti-inflammatory and anti-rheumatic drugs (89%). In a sub-analysis of the population, 'clinically irrelevant alert' was the most common reason for alert overrides in the ED (69.3%), and 'benefit assessed to be greater than the risk' was the most common reason in the GW (61.4%). CONCLUSIONS: We confirmed that the DDI alerts and the reasons for alert overrides differed by admitting department. Different strategies may be efficient for each admitting department.

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