Prediction of initiation time of corrosion in RC using meshless methods

Ling Yao,Lingling Zhang,Ling Zhang,Xiaolu Li 사단법인 한국계산역학회 2015 Computers and Concrete, An International Journal Vol.16 No.5

Degradation of reinforced concrete (RC) structures due to chloride penetration followed by reinforcement corrosion has been a serious problem in civil engineering for many years. The numerical simulation methods at present are mainly finite element method (FEM) and finite difference method (FDM), which are based on mesh. Mesh generation in engineering takes a long time. In the present article, the numerical solution of chloride transport in concrete is analyzed using radial point interpolation method (RPIM) and element-free Galerkin (EFG). They are all meshless methods. RPIM utilizes radial polynomial basis, whereas EFG uses the moving least-square approximation. A Galerkin weak form on global is used to attain the discrete equation, and four different numerical examples are presented. MQ function and appropriate parameters have been proposed in RPIM. Numerical simulation results are compared with those obtained from the finite element method (FEM) and analytical solutions. Two case of chloride transport in full saturated and unsaturated concrete are analyzed to test the practical applicability and performance of the RPIM and EFG. A good agreement is obtained among RPIM, EFG, and the experimental data. It indicates that RPIM and EFG are reliable meshless methods for prediction of chloride concentration in concrete structures.

Analysis of Uncertainty Influence on the Probabilistic Evaluation of Vortex-Induced Vibration Response of a Self-Anchored Suspension Bridge

Ling-yao Li 대한토목학회 2019 KSCE JOURNAL OF CIVIL ENGINEERING Vol.23 No.11

The uncertainty of the parameters involved in the bridge vortex-induced vibration (VIV) response is hard to be described accurately and the probabilistic description remains scarce. The present work aims at giving a contribution to the probabilistic evaluation of the bridge VIV response considering uncertainty influence of parameters. A self-anchored suspension bridge was selected as an example to analyze the uncertainty influence on the probabilistic evaluation of VIV response. The probability density function of the wind speed at the deck level of the bridge was established. The modal analysis was carried out and the natural vibration characteristics were checked. Then three performance functions involving different considerations of the maximum response models of bridge VIV were introduced. The numerical characteristics (coefficient of variation (COV), skewness and kurtosis) in the parameter space was propagated to access its influence on the exceeding probability of the bridge VIV response utilizing the second-order fourth-moment (SOFM) method. The influence from the different distribution type of the parameters was investigated. Results showed that the influence degree of COV, skewness and kurtosis of parameters on the exceeding probability of VIV response for the bridge is different and the distribution type of parameter has little effect based on the SOFM method.

Inflammatory Endotypes and Tissue Remodeling Features in Antrochoanal Polyps

Chen Cai-Ling,Wang Yu-Ting,Yao Yin,Pan Li,Guo Bei,Zhu Ke-Zhang,Ma Jin,Wang Nan,Li Xue-Li,Deng Yi-Ke,Liu Zheng 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.6

Purpose: The pathogenic mechanisms of antrochoanal polyps (ACPs) remain largely unknown. This study aimed to characterize inflammatory patterns and tissue remodeling features in ACPs. Methods: Inflammatory cell infiltration and tissue edema severity as well as fibrin deposition in ACPs and bilateral eosinophilic and noneosinophilic nasal polyps (NPs) were studied with immunohistochemical and immunofluorescence staining. Cytokine levels in sinonasal tissues were detected with the Bio-Plex assay. The expression of coagulation and fibrinolytic markers was measured using reverse-transcription polymerase chain reaction and enzyme-linked immunosorbent assays. Results: Compared to control tissues and bilateral eosinophilic and noneosinophilic NPs, ACPs had higher levels of neutrophil infiltration and expression of myeloperoxidase (MPO), interleukin (IL)-8 and interferon (IFN)-γ. In total, 94.4% of ACPs demonstrated an eosinophil cationic protein/MPO ratio of < 1, compared to 79.0% of noneosinophilic and 26% of eosinophilic NPs. Principle component and multiple correspondence analyses revealed a neutrophilic and type 1 inflammation pattern in ACPs. Compared to control tissues, edema scores and fibrin deposition were increased, whereas d-dimer and tissue plasminogen activator (tPA) levels were decreased in ACPs and bilateral NPs, with more prominent changes in ACPs even than in eosinophilic NPs. The tPA levels were negatively correlated with IFN-γ, IL-8, and MPO levels in ACPs. Neutrophils were the major cellular source of IFN-γ in ACPs, and the number of IFN-γ+ neutrophils was elevated in ACPs than in control tissues and bilateral eosinophilic and noneosinophilic NPs. Conclusions: ACPs are characterized by the neutrophilic and type 1 inflammation endotype. Neutrophil-derived IFN-γ is associated with reduced tPA production in ACPs.

Wnt/β-Catenin Promotes the Osteoblastic Potential of BMP9 Through Down-Regulating Cyp26b1 in Mesenchymal Stem Cells

Yao Xin-Tong,Li Pei-pei,Liu Jiang,Yang Yuan-Yuan,Luo Zhen-Ling,Jiang Hai-Tao,He Wen-Ge,Luo Hong-Hong,Deng Yi-Xuan,He Bai-Cheng 한국조직공학과 재생의학회 2023 조직공학과 재생의학 Vol.20 No.5

BACKGROUND: All-trans retinoic acid (ATRA) promotes the osteogenic differentiation induced by bone morphogenetic protein 9 (BMP9), but the intrinsic relationship between BMP9 and ATRA keeps unknown. Herein, we investigated the effect of Cyp26b1, a critical enzyme of ATRA degradation, on the BMP9-induced osteogenic differentiation in mesenchymal stem cells (MSCs), and unveiled possible mechanism through which BMP9 regulates the expression of Cyp26b1. METHODS: ATRA content was detected with ELISA and HPLC–MS/MS. PCR, Western blot, and histochemical staining were used to assay the osteogenic markers. Fetal limbs culture, cranial defect repair model, and micro–computed tomographic were used to evaluate the quality of bone formation. IP and ChIP assay were used to explore possible mechanism. RESULTS: We found that the protein level of Cyp26b1 was increased with age, whereas the ATRA content decreased. The osteogenic markers induced by BMP9 were increased by inhibiting or silencing Cyp26b1 but reduced by exogenous Cyp26b1. The BMP9-induced bone formation was enhanced by inhibiting Cyp26b1. The cranial defect repair was promoted by BMP9, which was strengthened by silencing Cyp26b1 and reduced by exogenous Cyp26b1. Mechanically, Cyp26b1 was reduced by BMP9, which was enhanced by activating Wnt/b-catenin, and reduced by inhibiting this pathway. b-catenin interacts with Smad1/5/9, and both were recruited at the promoter of Cyp26b1. CONCLUSIONS: Our findings suggested the BMP9-induced osteoblastic differentiation was mediated by activating retinoic acid signalling, viadown-regulating Cyp26b1. Meanwhile, Cyp26b1 may be a novel potential therapeutic target for the treatment of bone-related diseases or accelerating bone-tissue engineering.

4-Hydroxynonenal Promotes Growth and Angiogenesis of Breast Cancer Cells through HIF-1α Stabilization

Li, Yao-Ping,Tian, Fu-Guo,Shi, Peng-Cheng,Guo, Ling-Yun,Wu, Hai-Ming,Chen, Run-Qi,Xue, Jin-Ming Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.23

4-Hydroxynonenal (4-HNE) is a stable end product of lipid peroxidation, which has been shown to play an important role in cell signal transduction, while increasing cell growth and differentiation. 4-HNE could inhibit phosphatase and tensin homolog (PTEN) activity in hepatocytes and increased levels have been found in human invasive breast cancer. Here we report that 4-HNE increased the cell growth of breast cancer cells as revealed by colony formation assay. Moreover, vascular endothelial growth factor (VEGF) expression was elevated, while protein levels of hypoxia inducible factor 1 alpha (HIF-$1{\alpha}$) were up-regulated. Sirtuin-3 (SIRT3), a major mitochondria NAD+-dependent deacetylase, is reported to destabilize HIF-$1{\alpha}$. Here, 4-HNE could inhibit the deacetylase activity of SIRT3 by thiol-specific modification. We further demonstrated that the regulation by 4-HNE of levels of HIF-$1{\alpha}$ and VEGF depends on SIRT3. Consistent with this, 4-HNE could not increase the cell growth in SIRT3 knockdown breast cancer cells. Additionally, 4-HNE promoted angiogenesis and invasion of breast cancer cells in a SIRT3-dependent manner. In conclusion, we propose that 4-HNE promotes growth, invasion and angiogenesis of breast cancer cells through the SIRT3-HIF-$1{\alpha}$-VEGF axis.

Novel double-walled microspheres based on chitosan, sodium cellulose sulfate and sodium tripolyphosphate: Preparation, characterization and in vitro release study

Li-Ying Zhu,Xiao-Qin Yan,Hong-Man Zhang,Shan-Jing Yao,Ling Jiang 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.3

A novel double-walled microsphere composed of chitosan, sodium cellulose sulfate (NaCS) and sodiumtripolyphosphate (TPP) was prepared. TPP was used as ionic crosslinker. The morphology of the microspheres wasobserved by microscope and SEM, and the results showed that the double-walled microsphere was smooth outside,with rough interior surface. FTIR spectra analysis was performed to investigate the PEC formation among chitosan,NaCS, and TPP. In vitro release studies of BSA showed that the double-walled microspheres had regular and sustainablerelease profiles in simulated colonic fluid (SCF). Our results indicated that the double-walled microspheres preparedcould be used as a candidate protein drug carrier for the colon.

Multidetector CT Characteristics of Fumarate Hydratase-Deficient Renal Cell Carcinoma and Papillary Type II Renal Cell Carcinoma

Yang Ling,Li Xue-Ming,Hu Ya-Jun,Zhang Meng-Ni,Yao Jin,Song Bin 대한영상의학회 2021 Korean Journal of Radiology Vol.22 No.12

Objective: To investigate the multidetector computed tomography (MDCT) features of fumarate hydratase-deficient renal cell carcinoma (FH-deficient RCC) with germline or somatic mutations, and compare them with those of papillary type II RCC (pRCC type II). Materials and Methods: A total of 24 patients (mean ± standard deviation, 40.4 ± 14.7 years) with pathologically confirmed FH-deficient RCC (15 with germline and 9 with somatic mutations) and 54 patients (58.6 ± 12.6 years) with pRCC type II were enrolled. The MDCT features were retrospectively reviewed and compared between the two entities and mutation subgroups, and were correlated with the clinicopathological findings. Results: All the lesions were unilateral and single. Compared with pRCC type II, FH-deficient RCC was more prevalent among younger patients (40.4 ± 14.7 vs. 58.6 ± 12.6, p < 0.001) and tended to be larger (8.1 ± 4.1 vs. 5.4 ± 3.2, p = 0.002). Cystic solid patterns were more common in FH-deficient RCC (20/24 vs. 16/54, p < 0.001), with 16 of the 20 (80.0%) cystic solid tumors having showed typical polycystic and thin smooth walls and/or septa, with an eccentric solid component. Lymph node (16/24 vs. 16/54, p = 0.003) and distant (11/24 vs. 3/54, p < 0.001) metastases were more frequent in FH-deficient RCC. FHdeficient RCC and pRCC type II showed similar attenuation in the unenhanced phase. The attenuation in the corticomedullary phase (CMP) (76.3% ± 25.0% vs. 60.2 ± 23.6, p = 0.008) and nephrographic phase (NP) (87.7 ± 20.5, vs. 71.2 ± 23.9, p = 0.004), absolute enhancement in CMP (39.0 ± 24.8 vs. 27.1 ± 22.7, p = 0.001) and NP (50.5 ± 20.5 vs. 38.2 ± 21.9, p = 0.001), and relative enhancement ratio to the renal cortex in CMP (0.35 ± 0.26 vs. 0.24 ± 0.19, p = 0.001) and NP (0.43 ± 0.24 vs. 0.29 ± 0.19, p < 0.001) were significantly higher in FH-deficient RCC. No significant difference was found between the FH germline and somatic mutation subgroups in any of the parameters. Conclusion: The MDCT features of FH-deficient RCC were different from those of pRCC type II, whereas there was no statistical difference between the germline and somatic mutation subgroups. A kidney mass with a cystic solid pattern and metastatic tendency, especially in young patients, should be considered for FH-deficient RCC.

Hydroxylation of Compactin (ML-236B) by CYP105D7 (SAV_7469) from Streptomyces avermitilis^s

( Qiuping Yao ),( Li Ma ),( Ling Liu ),( Haruo Ikeda ),( Shinya Fushinobu ),( Shengying Li ),( Lian-hua Xu ) 한국미생물 · 생명공학회 2017 Journal of microbiology and biotechnology Vol.27 No.5

Compactin and pravastatin are competitive cholesterol biosynthesis inhibitors of 3-hydroxy-3- methylglutaryl-CoA reductase and belong to the statin drugs; however, the latter shows superior pharmacokinetic characteristics. Previously, we reported that the bacterial P450, CYP105D7, from Streptomyces avermitilis can catalyze the hydroxylation of 1-deoxypentalenic acid, diclofenac, and naringenin. Here, we demonstrate that CYP105D7 could also catalyze compactin hydroxylation in vitro. In the presence of both bacterial and cyanobacterial redox partner systems with an NADPH regeneration system, the reaction produced two hydroxylated products, including pravastatin (hydroxylated at the C6 position). The steadystate kinetic parameters were measured using the redox partners of putidaredoxin and its reductase. The K_m and k_cat values for compactin were 39.1 ± 8.8 μM and 1.12 ± 0.09 min^-1, respectively. The k_cat/K_m value for compactin (0.029 min^-1·μM^-1) was lower than that for diclofenac (0.114 min^-1·μM^-1). Spectroscopic analysis showed that CYP105D7 binds to compactin with a K_d value of 17.5 ± 3.6 μM. Molecular docking analysis was performed to build a possible binding model of compactin. Comparisons of different substrates with CYP105D7 were conclusively illustrated for the first time.

A Five-step Systematic Therapy for Treating Plugged Ducts and Mastitis in Breastfeeding Women: A Case–Control Study

Yuzhi Yao,Tianzhu Long,Yuhong Pan,Yin Li,Ling Wu,Benjie Fu,Hongmin Ma 한국간호과학회 2021 Asian Nursing Research Vol.15 No.3

Purpose: This study aimed to describe the clinical response to five-step systematic therapy (FSST) in the management of plugged ducts and mastitis. FSST was a comprehensive milk stasis dredging treatment, which contained five steps to make the milk out of the plugged duct. Methods: This retrospective study included 922 breastfeeding women, 714 with plugged ducts, and 208 with mastitis who received FSST from June to September 2017. The breast pain score, swelling degree, and range of breast induration were recorded pre-FSST and post-FSST. Results: After a single FSST, pain score and swelling degree were significantly improved (both p < .001) in all cases. After FSST, the mean breast pain relief score was 1.69 ± 0.70, whereas the mean swelling fade away degree was 1.61 ± 0.62. In the subgroup analysis, pain score and swelling degree were significantly improved (both p < .001) in the plugged ducts group and the mastitis group. The score of pain relief in the plugged ducts group was less than that in the mastitis group (1.63 ± 0.68 vs. 1.91 ± 0.70, t = 5.30; p < .001), whereas improvement of swelling fade away was greater in the plugged ducts group than the mastitis group (1.65 ± 0.64 vs. 1.48 ± 0.56, t = 3.49; p = .001). The composition ratio of changes in induration range between the two groups was statistically different (Pearson c2 = 137.87, p < .001), of which more obvious improvement in the plugged ducts group than the mastitis group (c2 = 25.65, p < .001). Conclusion: FSST can relieve pain, reduce breast swelling and range of induration, and for plugged ducts or mastitis varied degree differently

Expression Profiles of Class A Rice Heat Shock Transcription Factor Genes Under Abiotic Stresses

Ai-Ling Liu,Jie Zou,Xian-Wen Zhang,Xiao-Yun Zhou,Wen-Fang Wang,Xing-Yao Xiong,Li-Yun Chen,Xin-Bo Chen 한국식물학회 2010 Journal of Plant Biology Vol.53 No.2

Expression profiles of 12 class A rice heat shock transcription factor genes (OsHsfAs) were analyzed by semi-quantitative reverse transcriptase polymerase chain reaction. The OsHsfA genes exhibited tissue-specific expressions under normal condition. OsHsfA1a, A2d, and A9 were predominantly expressed in young spike. Expression responses of the 12 OsHsfAs under abiotic stresses were analyzed in the shoots of rice seedling. Most OsHsfA genes responded quickly to heat stress except for OsHsfA1a, A3,and A9 which were almost unaffected. In particular,OsHsfA2a expression in response to heat stress was highest among the heat shock factors examined. However, the majority of the increased OsHsfAs expression responses to salt, polyethylene glycol (PEG), and cold treatments primarily occurred during the later stages (3 to 24 h) of stress exposure. Furthermore, most of OsHsfA gene expressions were little affected and only a few (OsHsfA3, A4d, A7,and A9) genes had slow responses to cold treatment. The results indicate that the transcript levels of OsHsfAs during heat stress exposure were distinct from those of plants subjected to salt, PEG, and cold stresses, suggesting that there might be different regulatory networks between heat and non-heat stress.