Browsing by Author "Liao W.-C."

Cardiovascular diseases (atherosclerosis, stroke, myocardiac infarction etc.) are the major systemic diseases of elder peoples in the world. This is possibly due to increased levels of oxidized low-density lipoproteins (oxLDLs) such as 7-ketocholesterol (7-KC) and lysophosphatidylcholine (LPC) that damage vascular endothelial cells, induce inflammatory responses, to elevate the risk of cardiovascular diseases, Alzheimer's disease, and age-related macular degeneration. However the toxic effects of 7-KC on endothelial cells are not known. In this study, 7-KC showed cytotoxicity to endothelial cells at concentrations higher than 10 μg/ml. 7-KC stimulated ATM/Chk2, ATR-Chk1 and p53 signaling pathways in endothelial cells. 7-KC also induced G0/G1 cell cycle arrest and apoptosis with an inhibition of Cyclin dependent kinase 1 (Cdk1) and cyclin B1 expression. Secretion and expression of IL-8 in endothelial cells were stimulated by 7-KC. 7-KC further induced intracellular ROS production as shown by increase in DCF fluorescence and Akt phosphorylation. LY294002 attenuated the 7-KC-induced apoptosis and IL-8 mRNA expression of endothelial cells. These results indicate that oxLDLs such as 7-KC may contribute to the pathogenesis of atherosclerosis, thrombosis and cardiovascular diseases by induction of endothelial damage, apoptosis and inflammatory responses. These events are associated with ROS production, activation of ATM/Chk2, ATR/Chk1, p53 and PI3K/Akt signaling pathways.

Introduction A vertical root fracture (VRF) is a root fracture extending along the longitudinal axis of roots and is often noted in endodontically treated teeth. However, the clinical and radiographic characteristics of VRFs are not completely known. Methods A total of 65 teeth with 68 vertical fractured roots in 58 Chinese patients were investigated. The clinical examination records and radiographic images were reviewed in detail. Results A total of 24 male (41.38%) and 34 female (58.62%) patients aged 25–90?years (average = 57?years) were included; 51 (87.93%) and 7 (12.07%) patients exhibited 1 tooth and 2 teeth with VRFs, respectively, in the dentition. VRFs occurred mainly in the mesial root (20 roots, 57.14%) of the mandibular molars (29 teeth, 44.62%). Clinically, teeth with VRFs usually presented a periodontal probing depth >5?mm (44 teeth, 91.67%, P?

Neutralizing anti-interferon-γ autoantibody (nAIGA)-associated immunodeficiency is an emerging medical issue worldwide. In the present study, we describe and discuss the clinical features and outcomes of patients with nAIGAs and disseminated infections by nontuberculous mycobacteria (dNTM). We thoroughly reviewed the medical records of all patients. Microorganisms and nAIGAs were identified using previously described methods with modifications. All data were calculated and analyzed using SPSS software. Among 46 adult patients with dNTM infections, we identified 45 cases (97.8%) with nAIGAs. The average patient age was 58.6 years, and there was no sex predominance. Cervical lymphadenitis (81.8%) was the most common clinical manifestation. Endocrine disorder was the leading comorbidity (7 cases). Malignancies were found in 4 patients, and all of the malignancies originated from the T-cell/macrophage lineage. More than half of the identifiable isolates were slow-growing NTMs. Twenty-eight (62.2%) and 18 (40.0%) patients had a history of zoster and salmonellosis, respectively. A high proportion of patients with recurrent episodes of NTM infection or a history of zoster and dNTM infection had initial nAIGA titers ?10 -5 dilution (P<0.05). Twenty-seven patients (60.0%) required long-term antimycobacterial therapy and had at least 1 episode of recurrent NTM disease. No mortality was related to dNTM infection. In Taiwan, nAIGAs are a recently recognized mechanism of dNTM infection. Long term of antibiotic treatment and adherence to medical advice are necessary to improve the clinical outcome of patients with nAIGAs. ? 2016 Wolters Kluwer Health, Inc.

High strength reinforced concrete have been promoted and developed in recent years. Due to brittle nature of high strength concrete, higher amounts of transverse reinforcement are required to ensure the ductility of members. By adding steel fiber into high strength concrete, which is so-called steel fiber reinforced concrete (SFRC), shear strength and deformation capacity can be significantly improved and damage tolerance is also enhanced because cracks can be restrained effectively. Moreover, SFRC is expected to replace certain amount of transverse reinforcement for better construction workability. In this study, uniaxial compression tests of 24 SFRC panels were conducted to verify strut mechanism and behavior of SFRC in the isolated strut. The result results show that the addition of steel fiber not only changes the failure mode from brittle splitting failure to ductile strut crushing, but also increases both strengths at the first-cracking and ultimate stages. Furthermore, by analyzing different shapes of strut, an index named effective tie area is proposed to verify tensile force contributed from steel fiber in the bottle-shaped strut. The results indicate that in the specimen with 0.75% and 1.5% volume fraction of steel fiber, effective tie area can raise up to 40% and 50%, respectively. ? 2020, Chinese Institute of Civil and Hydraulic Engineering. All right reserved.

The ties configuration in accordance with every requirement of ACI 318-14 or newer for confinement and shear strength in a reinforced concrete (RC) column is strong required so that the RC column can dissipate seismic energy through flexural mechanism. In addition, according to ACI 318, the amount of confinement may increase as axial loading level increases. The increase of amount of confinement may lead to construction difficulties, particularly in column with small cross-section size; meanwhile, according to ACI 318, there is an upper limit for the transverse reinforcement in an RC column. An alternative material that has feasibility in substituting and reducing the traditional transverse reinforcement while maintaining shear strength and ductility is required. Application of short and discontinuous steel fibers to concrete element can be an alternative, since previous experimental results showed the improvement of shear strength, ductility, and toughness after adding steel fibers. However, no comprehensive experimental study of shear behavior of steel fiber reinforced concrete (SFRC) column with high strength concrete and steel reinforcing bars under different axial compression ratios subjected to lateral displacement reversals were available. In this study, large-scale double curvature SFRC columns with concrete strength design, yield strength for longitudinal reinforcement, and yield strength for transverse reinforcement, respectively of 70 MPa, 685 MPa (SD685), and 785 MPa (SD785) were prepared and tested. ? 2021 Elsevier Ltd

Extravillus trophoblast (EVT) invasion plays a critical role in placental development. Integrins bind to extracellular matrix (ECM) proteins to mediate EVT cell adhesion, migration, and invasion. Changes in O-glycans on β1-integrin have been found to regulate cancer cell behavior. We hypothesize that O-glycosyltransferases can regulate EVT invasion through modulating the glycosylation and function of β1-integrin. Here, we found that the GALNT1 and GALNT2 mRNA were highly expressed in HTR8/SVneo and first trimester EVT cells. Immunohistochemstry and immunofluorescence staining showed that GALNT2 was expressed in subpopulations of EVT cells in deciduas, but not in syncytiotrophoblasts and cytotrophoblasts of placental villi. The percentage of GALNT2-positive EVT cells increased with gestational ages. Overexpression of GALNT2 in HTR8/SVneo cells significantly enhanced cell-collagen IV adhesion, but suppressed cell migration and invasion. Notably, we found that GALNT2 increased the expression of Tn antigen (GalNAc-Ser/Thr) on β1-integrin as revealed by Vicia Villosa agglutinin (VVA) binding. Furthermore, GALNT2 suppressed the phosphorylation of focal adhesion kinase (FAK), a crucial downstream signaling molecule of β1-integrin. Our findings suggest that GALNT2 is a critical initiating enzyme of O-glycosylation for regulating EVT invasion. ? 2012 Elsevier Ltd. All rights reserved.

Background: The diagnosis of chronic thromboembolic pulmonary hypertension (CTEPH) is complex, and the modality of treatment is surgery and targeted medication. Patients with CTEPH could have a poor prognosis if their diagnosis or treatment is delayed. The incidence of CTEPH and its clinical features are largely unknown in Taiwan, even among other Asian populations. In this study, we aimed to investigate the geodemographics of CTEPH in Taiwan and describe the practical management and treatment outcomes in patients with CTEPH. Methods: This study retrospectively enrolled patients in the Taiwan cohort – Registry of CTEPH. The study was conducted over 2 years inclusive of follow-up. The enrolment criteria depended on the current global guideline. Results: From January 2018 to March 2020, 107 CTEPH patients enrolled in the Taiwan registry. All patients received right heart catheterisation examinations. The overall median age was 61.4 ± 16.5 years, and the cohort was dominated by female patients (75/107). Risk factors included pulmonary embolism (81.3%), deep vein thrombosis (22.4%), and previous major surgery (20.6%). Twenty-one (19.6%) patients underwent pulmonary endarterectomy operation alone, and 38 (35.5%) patients underwent balloon pulmonary angioplasty alone. Conclusion: To our knowledge, this is the first national cohort study that demonstrated the raw CTEPH incidence in Taiwan. It also showed the CTEPH incidence between male and female patients in the Asian population was different from the Caucasian population. ? 2021

A concrete-filled steel tube (CFT) combines the advantages of concrete and steel in construction and structural applications. However, research on the time-dependent deformation of the CFT under long-term sustained loading are still limited, particularly for stress transfer between the steel tube and concrete due to creep. This study investigated the creep behavior of CFT over a long period of 400 days. The creep and shrinkage strain of CFT was significantly lower than those of concrete that was not confined within a steel tube. The vertical strains of the steel tube and concrete core were almost identical, and it was shown that they were well bonded and acted as a composite. The vertical stress of steel increased by 32.7%, whereas the vertical stress of concrete decreased by 15.8% at 375 days. The stress transfer is notable and cannot be neglected in CFT design. Moreover, the results of creep and shrinkage were compared to prediction values of the B4 model and B4-TW model to verify their validity. ? 2021 by the authors. Licensee MDPI, Basel, Switzerland.

This paper investigated the influence of supplementary cementitious materials (SCM, including fly ash (FA), ground granulated blast-furnace slag (GGBS), metakaolin (MK)) on the microstructure and shrinkage behavior of high-performance concrete (HPC). The prediction accuracy of some typical shrinkage models and the correction factor kSCM were evaluated with statistical parameters RE and R2new. After analysis of shrinkage models, the kSCM*B4 model and kSCM*CEB were more suitable for the drying shrinkage and autogenous shrinkage of HPC, respectively. Although the activities of FA, GGBS, and MK were different, SCM were helpful to form a dense interfacial transition zone (ITZ) microstructure. To analyze comprehensively the effect of single or binary addition of SCM on its shrinkage properties, XRD, SEM, slump and compressive strength experiments of HPC were carried out. The diffraction peaks of Ca(OH)2 decreased with the content of FA and GGBS. The setting time of HPC was prolonged with the content of SCM. Both the decrease of FA and the increase of GGBS and MK could enhance the compressive strength of HPC. Drying shrinkage decreased with the content of FA, GGBS, and MK thanks to the refined microstructure with SCM. Autogenous shrinkage decreased remarkably with the content of FA and GGBS, however, that of MK was opposite. For the same total content of SCM, effects of binary addition of FA and MK, FA, and GGBS on the shrinkage behavior of HPC were more markedly than that of single FA. The drying shrinkage of HPC with single MK was slightly less than that with single GGBS, however, the autogenous shrinkage of HPC with single MK was significantly more than that with single GGBS. ? 2021 Elsevier Ltd