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1.
Nephrology (Carlton) ; 21(11): 968-974, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26617162

RESUMO

AIM: Hepatitis B virus (HBV) infection is an important risk factor for morbidity and mortality in the general population. However, limited data are available on the progression of HBV infection in patients with end-stage renal disease (ESRD), and available data are controversial. Therefore, we investigated the association between hepatitis B surface antigen (HBsAg) seropositivity and mortality in patients with incident ESRD. METHODS: All adult patients (≥18 years of age) starting dialysis for ESRD from January 2000 to December 2011 were included. A total of 1090 patients with ESRD were analyzed. HBsAg-positive patients were paired 1:6 with HBsAg-negative patients using propensity score matching. RESULTS: Eighty one (7.4%) patients were HBsAg positive. No differences in the survival rates of the HBsAg-positive and HBsAg-negative patients with ESRD were detected in either the entire cohort or the propensity score matched cohort. No differences in survival were detected between the groups of HBsAg-positive patients based on the hepatitis B envelope antigen, hepatitis B envelope antibody, HBV DNA status, or use of antiviral agents. No difference in mortality was found between the haemodialysis (HD) and peritoneal dialysis (PD) subgroups among HBsAg-positive patients. CONCLUSION: Our results suggest that hepatitis B surface antigenaemia is not related to increased mortality in patients with incident ESRD. Survival of HBsAg-positive patients undergoing PD was comparable to that of patients undergoing HD.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B , Falência Renal Crônica , Diálise Renal/estatística & dados numéricos , Adulto , Antivirais/uso terapêutico , Comorbidade , Feminino , Hepatite B/sangue , Hepatite B/diagnóstico , Hepatite B/tratamento farmacológico , Hepatite B/epidemiologia , Vírus da Hepatite B/imunologia , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Mortalidade , Pontuação de Propensão , Diálise Renal/métodos , República da Coreia/epidemiologia , Estudos Retrospectivos , Estatística como Assunto
2.
ACS Appl Mater Interfaces ; 16(24): 31543-31554, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38843450

RESUMO

To address the inherent brittleness of conventional transparent conductive oxides, researchers have focused on enhancing their flexibility. This is achieved by incorporating organic films to construct organic-inorganic hybrid layer-by-layer nanostructures, where the interlayer thickness and interface play pivotal roles in determining the properties. These factors are contingent on the type of material, processing conditions, and specific application requirements, making it essential to select the appropriate conditions. In this study, ZnO-zincone nanolaminate thin films were fabricated using atomic layer deposition and molecular layer deposition in various structural configurations. Transmission electron microscopy, X-ray diffraction, and scanning electron microscopy were used to conduct a thorough analysis of the thin-film growth and structural transformations resulting from the deposition conditions. Furthermore, the influence of structural differences at the interfaces on the mechanical properties of the films was investigated by employing both tensile and compression-bending fatigue tests. This comprehensive examination reveals noteworthy variations in the mechanical responses of the films. Thin films characterized by internal porosity and an intermixed amorphous structure demonstrated enhanced compressive toughness, whereas rigid organic layers improved flexibility. These findings offer valuable insights into the development of flexible, transparent multilayer films.

3.
Polymers (Basel) ; 14(5)2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35267684

RESUMO

In a high-pressure hydrogen environment, the sealing rubber material is swelled by hydrogen, and the mechanical and tribological properties are reduced, causing various problems in the sealing performance. The focus of this study was the effect of the filler type and content on the tribological characteristics of rubber after exposure to high-pressure hydrogen. Acrylonitrile butadiene rubber specimens were exposed to high-pressure hydrogen at 96.6 MPa, and the change in the amount of wear with time after exposure was observed. The wear test was performed using a pin-on-disc ball tip to measure the amount of wear before and after hydrogen exposure of the materials under fixed revolutions per minute and normal load. Scanning electron microscopy was used to observe the wear track and cross section of the specimen to examine the changes in the wear mechanism after hydrogen exposure and to analyze the wear mechanism for each filler. The results of this study are expected to contribute to the evaluation of the tribological properties of the sealing materials used in hydrogen environments.

4.
ACS Nano ; 16(7): 10509-10516, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35820202

RESUMO

We report a graphene oxide (GO)-based composite, featuring GO/cross-linking agent (CA) nanoparticles, inspired by a nacre-like hierarchical structure present in nature. The as-prepared GO/CA composite was powdered to nanoscale particles and then mixed with pure GO to be GO/CA/GO (GCG) composite forming hierarchical GO/CA nanoasperities on the GO surface. The strength and toughness of the nacre-inspired GCG composite films were simultaneously improved by adjusting the nanoparticle concentration and hierarchical level of the GO-based films. Compared to pristine GO films and GO/CA composites, which exhibit a low level of hierarchy in their structures, the tensile strength and toughness of the GCG composites with higher hierarchy were enhanced 3.1 and 1.6 times and 47.6 and 10.9 times, respectively. Furthermore, a plausible mechanism of increasing mechanical properties based on nanoscale asperities and homogeneous interactions between GO and CA has been discussed.

5.
Polymers (Basel) ; 13(22)2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34833233

RESUMO

Automotive coatings, which comprise multiple layers, i.e., primer, base coating, and clear coat layers, are exposed to various environmental conditions that pose various types of damages to them. In particular, the outer layer of the automotive coating, i.e., the clear coat, is affected significantly by such damages. Therefore, a reliable and durable clear coat must be developed to improve the appearance of automobiles. In this study, a new clear coat based on an acrylic-based clear coat modified using polyrotaxane crosslinkers, which are necklace-shaped supramolecules composed of ring-shaped host molecules, is developed and characterized. The effects of polyrotaxane and silane on the scratch properties and mechanisms of the clear coating are analyzed. It is observed that the critical loads of the clear coat from scratch tests can be improved by adding optimal molecular necklace crosslinkers comprising silane functional groups. The improvement in the scratch properties of the modified acrylic-based clear coat may be attributed to the crosslinking characteristics and dynamic molecular movements of the polyrotaxane. In addition, the effects of environmental factors on the scratch characteristics of the modified acrylic-based clear coat are investigated by addressing the scratch durability of the clear coat.

6.
ACS Appl Mater Interfaces ; 11(30): 27306-27317, 2019 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-31241308

RESUMO

A flexible hard coating material displaying extreme scratch resistance and foldable flexibility was developed via the design of an organic-inorganic hybrid coating material employing an alkoxysilyl-functionalized polyrotaxane cross-linker (PRX_Si1). PRX_Si1 has a molecular necklace-like structure that can form organic-inorganic cross-linking points and provide large molecular movements. It was postulated that the scratch resistance and flexibility could be simultaneously increased because of the hybrid cross-linking points and dynamic molecular movements. To confirm this hypothesis, the crystalline structure and mechanical properties of the PRX_Si1-based hard coating material were analyzed via transmission electron microscopy, small-angle X-ray diffraction, tensile, pencil hardness, and scratch tests. Finally, the PRX_Si1-based hard coating material could form homogeneously dispersed nanoscale siloxane crystalline domains, and the strain at the break point was 3 times higher than that of a commercial hard coating material, resulting in no defect formation even after 5000 folding test runs. Moreover, the material displayed extremely high pencil hardness (9H) and scratch resistance.

7.
PLoS One ; 11(2): e0150145, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26914918

RESUMO

Vascular calcification is an important factor associated with mortality in dialysis patients. Recently, soluble receptor for advanced glycation end product (sRAGE) and extracellular RAGE binding protein S100A12 (EN-RAGE) have been reported to be involved in the process of vascular calcification. Therefore, we investigated whether sRAGE and S100A12 are useful indicators of progression of abdominal aortic calcification in hemodialysis (HD) patients. We analyzed annual changes in vascular calcification score (VCS) for up to 4 years, compared to clinical and biological parameters in 149 HD patients. VCS was assessed annually using plain X-ray images of the lateral lumbar spine. The progression group was defined as patients with an increase in VCS more than 1 point each year on average during the observation period. Time-averaged concentrations were also evaluated to examine the association between biological parameters and changes in VCS. The patients had a mean age of 58.59 ± 12.93 years; 53.7% were male, and 45% were diabetic. The VCS increased in 55 patients; the mean increase was 1.60 ± 2.91 points. In a stepwise multivariate logistic analysis, we found that higher levels of S100A12 were significantly associated with progression of VCS (odds ratio [OR], 2.622; 95% confidence interval [CI], 1.371-5.016; P = 0.004). The relationship between sRAGE and VCS was not statistically significant (OR, 0.644; 95% CI, 0.302-1.374; P = 0.255). Our findings suggest that serum levels of S100A12 are associated with progression of abdominal aortic calcification in HD patients, independent of sRAGE level.


Assuntos
Aorta Abdominal/diagnóstico por imagem , Receptor para Produtos Finais de Glicação Avançada/sangue , Diálise Renal/efeitos adversos , Proteína S100A12/sangue , Calcificação Vascular/diagnóstico por imagem , Aorta Abdominal/fisiopatologia , Biomarcadores/sangue , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radiografia , Fatores de Risco , Calcificação Vascular/sangue , Calcificação Vascular/fisiopatologia
8.
Head Neck ; 38(4): 582-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25488415

RESUMO

BACKGROUND: Recurrent laryngeal nerve (RLN) palsy is the most serious complication after thyroidectomy. However, little is known about the degree of traction injury that causes loss of signal. The purpose of this study was to evaluate traction injuries in the swine RLN using continuous intraoperative neuromonitoring (IONM) and determine the traction power that results in loss of signal. METHODS: Thirteen swine underwent traction injury to the RLNs with continuous IONM, and stress-strain curves were determined for 8 nerves using the universal material testing machine in an ex vivo model. RESULTS: Traction injury at a mean power of 2.83 MPa caused loss of signal. The mean physiologic limit strain and tensile strength of the swine RLNs were found to be 15.0% and 4.9 MPa, respectively. Histological analysis showed no abnormal structural findings. CONCLUSION: Traction injury of swine RLNs causes loss of signal at a power of 2.83 MPa. However, all injured nerves recovered within 7 days with no observed structural damage.


Assuntos
Modelos Animais de Doenças , Monitorização Intraoperatória/métodos , Traumatismos do Nervo Laríngeo Recorrente/diagnóstico , Nervo Laríngeo Recorrente/fisiopatologia , Animais , Eletromiografia , Traumatismos do Nervo Laríngeo Recorrente/etiologia , Traumatismos do Nervo Laríngeo Recorrente/fisiopatologia , Suínos , Tireoidectomia/efeitos adversos , Tração
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