Risk Factors of Rehemorrhage in Postoperative Patients with Spontaneous Intracerebral Hemorrhage : A Case-Control Study

Ren, Yanming,Zheng, Jun,Liu, Xiaowei,Li, Hao,You, Chao The Korean Neurosurgical Society 2018 Journal of Korean neurosurgical society Vol.61 No.1

Objective : Rehemorrhage is the most severe complication of postoperative patients with spontaneous intracerebral hemorrhage. The aim of the present study was to assess independent predictors of rehemorrhage and find the possibility of preventing rehemorrhage in postoperative patients with spontaneous intracerebral hemorrhage (sICH). Methods : Medical records of 263 postoperative patients with sICH from our Hospital were reviewed. The relationships between rehemorrhage and parameters were examined by univariate and multivariate analyses. The parameters include time from onset to surgery, hematologic paremeters, neuroimaging characteristics, level and variability of systolic blood pressure, medical histories, operation duration, and blood loss. In addition, relationship between rehemorrhage and clinical outcome were analyzed by using multivariate analyses. Results : Thirty-five (13.31%) patients experienced rehemorrhage after operation. Multivariate analyses indicated that the following factors were independently associated with rehemorrhage : history of diabetes mellitus (odds ratio [OR], 2.717; 95% confidence interval [CI], 1.005-7.346; p=0.049), and midline shift (for every 1 mm increase, OR, 1.117; 95% CI, 1.029-1.214; p=0.009). Rehemorrhage was an independent risk factor of poor functional outcome (OR, 3.334; 95% CI, 1.094-10.155; p=0.034). Conclusion : Our finding revealed that history of diabetes mellitus and admission midline shift were possibly associated with rehemorrhage in postoperative patients with sICH.

Endoscopic Submucosal Tunnel Dissection for Upper Gastrointestinal Submucosal Tumors Originating from the Muscularis Propria Layer: A Single-Center Study

( Xiaowei Tang ),( Yutang Ren ),( Silin Huang ),( Qiaoping Gao ),( Jieqiong Zhou ),( Zhengjie Wei ),( Bo Jiang ),( Wei Gong ) 대한간학회 2017 Gut and Liver Vol.11 No.5

Background/Aims: In recent years, endoscopic submucosal tunnel dissection (ESTD) has gained popularity worldwide. The aim of this study was to evaluate the safety and efficacy of ESTD in treating upper gastrointestinal submucosal tu-mors (SMTs) in a large-volume endoscopic center. Methods: Patients with SMTs were enrolled in this study between January 2012 and January 2015. Demographic data, clinical data, and treatment outcome were collected and analyzed. Results: Seventy SMTs originating from the muscularis pro-pria (MP) layer were identified in 69 patients. All patients successfully underwent the ESTD procedure. The mean procedure time was 49.0±29.5 minutes, and the mean tu-mor size was 18.7±7.2 mm. Among all lesions, the majority (70.0%) were located in the esophagus, 12.9% in the cardia, and 17.1% in the stomach. Complete resection was achieved in 67 lesions (95.7%). Perforation occurred in three patients (4.3%), who were treated by endoclips. Pneumothorax oc-curred in two patients (2.9%) and was successfully managed by thoracic drainage. During a median follow-up of 18.1 months, patients were free of local recurrence or distant metastasis. Conclusions: Our results demonstrated the fea-sibility and safety of ESTD in treating upper gastrointestinal SMTs originating from the MP layer. Large-scale comparative studies with other treatment methods should be conducted in the future. (Gut Liver 2017;11:620-627)

Changes in force associated with the amount of aligner activation and lingual bodily movement of the maxillary central incisor

Xiaowei Li,Chaochao Ren,Zheyao Wang,Pai Zhao,Hongmei Wang,Yuxing Bai 대한치과교정학회 2016 대한치과교정학회지 Vol.46 No.2

Objective: The purposes of this study were to measure the orthodontic forces generated by thermoplastic aligners and investigate the possible influences of different activations for lingual bodily movements on orthodontic forces, and their attenuation. Methods: Thermoplastic material of 1.0-mm in thickness was used to manufacture aligners for 0.2, 0.3, 0.4, 0.5, and 0.6 mm activations for lingual bodily movements of the maxillary central incisor. The orthodontic force in the lingual direction delivered by the thermoplastic aligners was measured using a micro-stress sensor system for the invisible orthodontic technique, and was monitored for 2 weeks. Results: Orthodontic force increased with the amount of activation of the aligner in the initial measurements. The attenuation speed in the 0.6 mm group was faster than that of the other groups (p < 0.05). All aligners demonstrated rapid relaxation in the first 8 hours, which then decreased slowly and plateaued on day 4 or 5. Conclusions: The amount of activation had a substantial influence on the orthodontic force imparted by the aligners. The results suggest that the activation of lingual bodily movement of the maxillary central incisor should not exceed 0.5 mm. The initial 4 or 5 days is important with respect to orthodontic treatment incorporating an aligner.

Determining Optimum Number of Gyrations for Porous Asphalt Mixtures Using Superpave Gyratory Compactor

Xiaowei Wang,Jiaxing Ren,Xinyu Hu,Xingyu Gu,Ning Li 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.6

The compaction characteristics of porous asphalt (PA) mixtures are significantly different from those of traditional dense-graded asphalt mixtures. Compaction efforts are critical for PA mixtures to exhibit good performance in terms of strength, functionality, and durability. The objective of this study was to determine the optimum number of gyrations for typical PA mixtures compacted using a Superpave gyratory compactor. The compaction characteristics and the influence of seven gyration levels on the indicators of air voids (AV) content, Marshall Stability (MS), multi-directional permeability, stone-on-stone contact, and durability of PA mixture were investigated through laboratory experiments. A multi-directional permeameter was designed to evaluate the multi-directional permeability of PA mixtures, including vertical, horizontal, and combined horizontal-vertical permeability. The AV content, multi-directional permeability decreases with the increasing gyrations. Based on the requirements of each indicator, the minimum and maximum gyrations for each indicator were determined. Balancing the performance of strength, functionality, and durability, the optimum number of gyrations for the PA mixtures was determined to be between 45 and 75 gyrations, which allows for different gyrations depending on the application of the PA mixture. Finally, the requirements of MS, horizontal permeability, and combined horizontal-vertical permeability are recommended for improving the performance of PA mixture.

Myotomy of Distal Esophagus Influences Proximal Esophageal Contraction and Upper Esophageal Sphincter Relaxation in Patients with Achalasia After Peroral Endoscopic Myotomy

( Yutang Ren ),( Xiaowei Tang ),( Fengping Chen ),( Zhiliang Deng ),( Jianuan Wu ),( Soma Nei ),( Bo Jiang ),( Wei Gong ) 대한소화기기능성질환·운동학회 2016 Journal of Neurogastroenterology and Motility (JNM Vol.22 No.1

Background/Aims The motility change after peroral endoscopic myotomy (POEM) in achalasia is currently focused on lower esophageal sphincter (LES). This study aims to investigate the correlation of motility response between distal and proximal esophagus after POEM. Methods A total of 32 achalasia patients who received POEM and high-resolution manometry (HRM) were included for analysis. Eckardt score was used to assess symptom improvement. HRM was applied for studying motility. Main parameters analyzed were (1) LES: resting pressure (restP), 4-second integrated relaxation pressure; (2) esophageal body (EB): contractile integral of distal segment with myotomy (CI-DM) and proximal segment without myotomy (CI-PNM); and (3) upper esophageal sphincter (UES): relaxation pressure (UES-RP). Results There were 6 type I, 17 type II, and 9 type III achalasia patients included for analysis. (1) Eckardt score, LES tone, CI-DM, CI-PNM and UES-RP were reduced remarkably after POEM (P < 0.001). (2) no significant correlation was noted between LES tone and contractile intergral of EB. (3) a positive linear correlation of CI-DM and CI-PNM changes was detected (P < 0.001). (4) the change of UES-RP was positively correlated with the change of contractile integral of EB (P < 0.001). Conclusions Myotomy of the distal esophagus would attenuate proximal EB contraction and assist UES relaxation in achalasia patients after POEM. (J Neurogastroenterol Motil 2016;22:78-85)

Investigation on crack propagation properties of flange-stiffened plate structure in a sleeve

Qinglin Lian,Huaji Wang,Xiaowei Ren,Xiaochen Fan,Dingshi Li,Jinbiao Zhao,Long Ju,Guodong Zhang 대한기계학회 2021 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.35 No.11

A 3D FE model has been developed to investigate the crack propagation properties of flange-stiffened plate structure in a sleeve used for loading transition, according to practical observations of the crack morphology. The stress intensity factor (SIF) was applied to analyze the crack propagation properties along crack tip in different positions of the sleeve;simulation models including either one crack or multiple cracks were studied. Results showed that crack formation had insignificant influence on the structural effective stress and deformation variations. The faces of the crack formed at the bolt hole edge were opened, meanwhile the crack possessed the highest potential to grow, while cracks in the connecting fillet between flange and stiffened plate and the flange mounting interface were less likely to propagate. Compared with the one-crack model, when multiple cracks co-existed there were limited changes on the crack respective propagation properties.

Efficacy and Safety of Peroral Endoscopic Myotomy in Achalasia Patients with Failed Previous Intervention: A Systematic Review and Meta-analysis

( Shali Tan ),( Chunyu Zhong ),( Yutang Ren ),( Xujuan Luo ),( Jin Xu ),( Xiangsheng Fu ),( Yan Peng ),( Xiaowei Tang ) 대한소화기학회 2021 Gut and Liver Vol.15 No.2

Peroral endoscopic myotomy (POEM) has emerged as a rescue treatment for recurrent or persistent achalasia after failed initial management. Therefore, we aimed to investigate the efficacy and safety of POEM in achalasia patients with failed previous intervention. We searched the MEDLINE, Embase, Cochrane, and PubMed databases using the queries “achalasia,” “peroral endoscopic myotomy,” and related terms in March 2019. Data on technical and clinical success, adverse events, Eckardt score and lower esophageal sphincter (LES) pressure were collected. The pooled event rates, mean differences (MDs) and risk ratios (RR) were calculated. A total of 15 studies with 2,276 achalasia patients were included. Overall, the pooled technical success, clinical success and adverse events rate of rescue POEM were 98.0% (95% confidence interval [CI], 96.6% to 98.8%), 90.8% (95% CI, 88.8% to 92.4%) and 10.3% (95% CI, 6.6% to 15.8%), respectively. Seven studies compared the clinical outcomes of POEM between previous failed treatment and the treatment naïve patients. The RR for technical success, clinical success, and adverse events were 1.00 (95% CI, 0.98 to 1.01), 0.98 (95% CI, 0.92 to 1.04), and 1.17 (95% CI, 0.78 to 1.76), respectively. Overall, there was significant reduction in the pre- and post-Eckardt score (MD, 5.77; p<0.001) and LES pressure (MD, 18.3 mm Hg; p<0.001) for achalasia patients with failed previous intervention after POEM. POEM appears to be a safe, effective and feasible treatment for individuals who have undergone previous failed intervention. It has similar outcomes in previously treated and treatment-naïve achalasia patients. (Gut Liver 2021;15:153-167)

Cu2O Nanoparticles and Multi-Branched Nanowires as Anodes for Lithium-Ion Batteries

Xu Chen,Chunxin Yu,Xiaojiao Guo,Qinsong Bi,Muhammad Sajjad,Yang Ren,Xiaowei Zhou,Zhu Liu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.09

Novelty Cu2O multi-branched nanowires and nanoparticles with size ranging from ~15 nm to ~60 nm have been synthesized by one-step hydrothermal process. These Cu2O nanostructures when used as anode materials for lithium-ion batteries exhibit the excellent electrochemical cycling stability and reduced polarization during the repeated charge/discharge process. The specific capacity of the Cu2O nanoparticles, multi-branched nanowires and microscale are maintained at 201.2 mAh/g, 259.6mAh/g and 127.4 mAh/g, respectively, under the current density of 0.1 A/g after 50 cycles. The enhanced electrochemical performance of the Cu2O nanostructures compared with microscale counterpart can be attributed to the larger contact area between active Cu2O nanostructures/electrolyte interface, shorter diffusion length of Li+ within nanostructures and the improved stress release upon lithiation/delithiation.