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      • KCI등재

        Effect of Different Cooling Rates in High Rheological Rate Forming Process on Mechanical Properties of Zr57Cu20Al10Ni8Ag5 Bulk Metallic Glass

        Xiao‑Bo Mei,Bao‑Chuan Liu,Wei Jiang,Quan Xu,Qi‑Dong Zhang,Yu‑Bai Ma,Fang‑Qiu Zu 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.9

        The influence of cooling rates on the mechanical properties of a Zr-based bulk metallic glass prepared with high rheologicalrate forming (HRRF) was investigated and compared with traditional suction cast methods. Amorphous samples of Zr57Cu-20Ni8Al10Ag5 were prepared in copper molds with different sizes in order to obtain different cooling rates for both HRRFand traditional cast methods. These specimens were subjected to compression experiments, including microhardness testing,X-ray diffraction testing and differential scanning calorimetry analysis. The results indicate that the plasticity of the samplesformed by HRRF are higher than that of the as-cast ones at the same cooling rates, while the microhardness manifests theopposite principle. As the cooling rate increases further, the difference in plasticity further increases between two methods,indicating that the plasticity of metallic glasses is more sensitive to cooling rates during the HRRF process. At the core ofthis phenomenon is the fact that HRRF methods can introduce more free volume into glasses than traditional cast methodswith an elevated cooling rate are able to.

      • KCI등재

        Follow-Up of 58 Traumatic Carotid-Cavernous Fistulas after Endovascular Detachable-Balloon Embolization at a Single Center

        Xiao-Quan Xu,Sheng Liu,Qing-Quan Zu,Lin-Bo Zhao,Jin-Guo Xia,Chun-Gao Zhou,Wei-Zhong Zhou,Hai-Bin Shi 대한신경과학회 2013 Journal of Clinical Neurology Vol.9 No.2

        Background and Purpose This study evaluated the clinical value of detachable-balloon embolization for traumatic carotid-cavernous fistula (TCCF), focusing on the frequency, risk factors, and retreatment of recurrence. Methods Fifty-eight patients with TCCF underwent transarterial detachable-balloon embolization between October 2004 and March 2011. The clinical follow-up was performed every 3months until up to 3 years postprocedure. Each patient was placed in either the recurrence group or the nonrecurrence group according to whether a recurrence developed after the first procedure. The relevant factors including gender, fistula location, interval between trauma and the interventional procedure, blood flow in the carotid-cavernous fistula, number of balloons, and whether the internal carotid artery (ICA) was sacrificed were evaluated. Results All 58 TCCFs were successfully treated with transarterial balloon embolization, including 7 patients with ICA sacrifice. Recurrent fistulas occurred in seven patients during the follow-up period. Univariate analysis indicated that the interval between trauma and the interventional procedure (p=0.006) might be the main factor related to the recurrence of TCCF. The second treatments involved ICA sacrifice in two patients, fistula embolization with balloons in four patients, and placement of a covered stent in one patient. Conclusions Detachable balloons can still serve as the first-line treatment for TCCFs and recurrent TCCFs despite having a nonnegligible recurrence rate. Shortening the interval between trauma and the interventional procedure may reduce the risk of recurrence.

      • KCI등재

        Correlation between Intravoxel Incoherent Motion Magnetic Resonance Imaging Derived Metrics and Serum Soluble CD40 Ligand Level in an Embolic Canine Stroke Model

        Xiao-Quan Xu,Chen-Jiang Wu,Shan-Shan Lu,Qian-Qian Gao,Qing-Quan Zu,Xing-Long Liu,Hai-Bin Shi,Sheng Liu 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.5

        Objective: To determine the relationship between intravoxel incoherent motion (IVIM) imaging derived quantitative metrics and serum soluble CD40 ligand (sCD40L) level in an embolic canine stroke model. Materials and Methods: A middle cerebral artery occlusion model was established in 24 beagle dogs. Experimental dogs were divided into low- and high-sCD40L group according to serum sCD40L level at 4.5 hours after establishing the model. IVIM imaging was scanned at 4.5 hours after model establishment using 10 b values ranging from 0 to 900 s/mm2. Quantitative metrics diffusion coefficient (D), pseudodiffusion coefficient (D*), and perfusion fraction (f) of ischemic lesions were calculated. Quantitative metrics of ischemic lesions were normalized by contralateral hemisphere using the following formula: normalized D = Dstroke / Dcontralateral. Differences in IVIM metrics between the low- and high-sCD40L groups were compared using t test. Pearson’s correlation analyses were performed to determine the relationship between IVIM metrics and serum sCD40L level. Results: The high-sCD40L group showed significantly lower f and normalized f values than the low-sCD40L group (f, p < 0.001; normalized f, p < 0.001). There was no significant difference in D*, normalized D*, D, or normalized D value between the two groups (All p > 0.05). Both f and normalized f values were negatively correlated with serum sCD40L level (f, r = -0.789, p < 0.001; normalized f, r = -0.823, p < 0.001). However, serum sCD40L level had no significant correlation with D*, normalized D*, D, or normalized D (All p > 0.05). Conclusion: The f value derived from IVIM imaging was negatively correlated with serum sCD40L level. f value might serve as a potential imaging biomarker to assess the formation of microvascular thrombosis in hyperacute period of ischemic stroke.

      • KCI등재

        Diffusion Weighted Imaging for Differentiating Benign from Malignant Orbital Tumors: Diagnostic Performance of the Apparent Diffusion Coefficient Based on Region of Interest Selection Method

        Xiao-Quan Xu,Hao Hu,Guo-Yi Su,Hu Liu,Hai-Bin Shi,Fei-Yun Wu 대한영상의학회 2016 Korean Journal of Radiology Vol.17 No.5

        Objective: To evaluate the differences in the apparent diffusion coefficient (ADC) measurements based on three different region of interest (ROI) selection methods, and compare their diagnostic performance in differentiating benign from malignant orbital tumors. Materials and Methods: Diffusion-weighted imaging data of sixty-four patients with orbital tumors (33 benign and 31 malignant) were retrospectively analyzed. Two readers independently measured the ADC values using three different ROIs selection methods including whole-tumor (WT), single-slice (SS), and reader-defined small sample (RDSS). The differences of ADC values (ADC-ROIWT, ADC-ROISS, and ADC-ROIRDSS) between benign and malignant group were compared using unpaired t test. Receiver operating characteristic curve was used to determine and compare their diagnostic ability. The ADC measurement time was compared using ANOVA analysis and the measurement reproducibility was assessed using Bland-Altman method and intra-class correlation coefficient (ICC). Results: Malignant group showed significantly lower ADC-ROIWT, ADC-ROISS, and ADC-ROIRDSS than benign group (all p < 0.05). The areas under the curve showed no significant difference when using ADC-ROIWT, ADC-ROISS, and ADC-ROIRDSS as differentiating index, respectively (all p > 0.05). The ROISS and ROIRDSS required comparable measurement time (p > 0.05), while significantly shorter than ROIWT (p < 0.05). The ROISS showed the best reproducibility (mean difference ± limits of agreement between two readers were 0.022 [-0.080–0.123] x 10-3 mm2/s; ICC, 0.997) among three ROI methods. Conclusion: Apparent diffusion coefficient values based on the three different ROI selection methods can help to differentiate benign from malignant orbital tumors. The results of measurement time, reproducibility and diagnostic ability suggest that the ROISS method are potentially useful for clinical practice.

      • KCI등재

        Intravoxel Incoherent Motion MR Imaging in the Head and Neck: Correlation with Dynamic Contrast-Enhanced MR Imaging and Diffusion-Weighted Imaging

        Xiao Quan Xu,최영준,성유섭,윤라경,장승원,박지은,허영진,백정환,이정현 대한영상의학회 2016 Korean Journal of Radiology Vol.17 No.5

        Objective: To investigate the correlation between perfusion- and diffusion-related parameters from intravoxel incoherent motion (IVIM) and those from dynamic contrast-enhanced MR imaging (DCE-MRI) and diffusion-weighted imaging in tumors and normal muscles of the head and neck. Materials and Methods: We retrospectively enrolled 20 consecutive patients with head and neck tumors with MR imaging performed using a 3T MR scanner. Tissue diffusivity (D), pseudo-diffusion coefficient (D*), and perfusion fraction (f) were derived from bi-exponential fitting of IVIM data obtained with 14 different b-values in three orthogonal directions. We investigated the correlation between D, f, and D* and model-free parameters from the DCE-MRI (wash-in, Tmax, Emax, initial AUC60, whole AUC) and the apparent diffusion coefficient (ADC) value in the tumor and normal masseter muscle using a whole volume-of-interest approach. Pearson’s correlation test was used for statistical analysis. Results: No correlation was found between f or D* and any of the parameters from the DCE-MRI in all patients or in patients with squamous cell carcinoma (p > 0.05). The ADC was significantly correlated with D values in the tumors (p < 0.001, r = 0.980) and muscles (p = 0.013, r = 0.542), despite its significantly higher value than D. The difference between ADC and D showed significant correlation with f values in the tumors (p = 0.017, r = 0.528) and muscles (p = 0.003, r = 0.630), but no correlation with D* (p > 0.05, respectively). Conclusion: Intravoxel incoherent motion shows no significant correlation with model-free perfusion parameters derived from the DCE-MRI but is feasible for the analysis of diffusivity in both tumors and normal muscles of the head and neck.

      • 8q24 rs4242382 Polymorphism is a Risk Factor for Prostate Cancer among Multi-Ethnic Populations: Evidence from Clinical Detection in China and a Meta-analysis

        Zhao, Cheng-Xiao,Liu, Ming,Xu, Yong,Yang, Kuo,Wei, Dong,Shi, Xiao-Hong,Yang, Fan,Zhang, Yao-Guang,Wang, Xin,Liang, Si-Ying,Zhao, Fan,Zhang, Yu-Rong,Wang, Na-Na,Chen, Xin,Sun, Liang,Zhu, Xiao-Quan,Yuan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.19

        Background: Evidence supporting an association between the 8q24 rs4242382-A polymorphism and prostate cancer (PCa) risk has been reported in North American and Europe populations, though data from Asian populations remain limited. We therefore investigated this association by clinical detection in China, and meta-analysis in Asian, Caucasian and African-American populations. Materials and Methods: Blood samples and clinical information were collected from ethnically Chinese men from Northern China with histologically-confirmed PCa (n=335) and from age-matched normal controls (n=347). The 8q24 (rs4242382) gene polymorphism was genotyped by polymerase chain reaction-high-resolution melting analysis. We initially analyzed the associations between the risk allele and PCa and clinical covariates. A meta-analysis was then performed using genotyping data from a total of 1,793 PCa cases and 1,864 controls from our study and previously published studies in American and European populations, to determine the association between PCa and risk genotype. Results: The incidence of the risk allele was higher in PCa cases than controls (0.222 vs 0.140, $P=7.3{\times}10^{-5}$), suggesting that the 8q24 rs4242382-A polymorphism was associated with PCa risk in Chinese men. The genotypes in subjects were in accordance with a dominant genetic model (ORadj=2.03, 95%CI: 1.42-2.91, $Padj=1.1{\times}10^{-4}$). Presence of the risk allele rs4242382-A at 8q24 was also associated with clinical covariates including age at diagnosis ${\geq}65$ years, prostate specific antigen >10 ng/ml, Gleason score <8, tumor stage and aggressive PCa, compared with the non-risk genotype ($P=4.6{\times}10^{-5}-3.0{\times}10^{-2}$). Meta-analysis confirmed the association between 8q24 rs4242382-A polymorphism and PCa risk (OR=1.62, 95%CI: 1.39-1.88, $P=1.0{\times}10^{-5}$) across Asian, Caucasian and African American populations. Conclusions: The replicated data suggest that the 8q24 rs4242382-A variation might be associated with increased PCa susceptibility in Asian, Caucasian and African American populations. These results imply that this polymorphism may be a useful risk biomarker for PCa in multi-ethnic populations.

      • KCI등재

        Multilocus Sequence Typing and Virulence Factors Analysis of Escherichia coli O157 Strains in China

        Xiao W. Ji,Ya L. Liao,Ye F. Zhu,Hai G. Wang,Ling Gu,Jiang Gu,Chen Dong,Hong L. Ding,Xu H. Mao,Feng C. Zhu,Quan M. Zou 한국미생물학회 2010 The journal of microbiology Vol.48 No.6

        Escherichia coli O157:H7, an important food-borne pathogen, has become a major public health concern worldwide. The aim of this study was to investigate the molecular epidemiologic feature of E. coli O157:H7strains in China. 105 E. coli O157:H7 isolates were collected from various hosts and places over 9 years. A multilocus sequence typing scheme (MLST) was applied for bacteria genotyping and polymerase chain reaction (PCR) was used for virulence factor identification. Seven new MLST sequence types (STs), namely ST836, ST837, ST838, ST839, ST840, ST841, and ST842 were identified, which grouped into two lineages. Phylogenetic analysis suggested that the most two frequent STs in China, ST837 and ST836, may be the derivatives of E. coli O157:H7 Sakai or E. coli O157:H7 EDL933. Geographical diversity and host variety of E. coli O157:H7 were observed in China. In addition, the different distribution of tccp was detected. The data presented herein provide new insights into the molecular epidemiologic feature of E. coli O157:H7, and aid in the investigation of the transmission regularity and evolutionary mechanism of E. coli O157:H7.

      • Clinical Study of Tumor Angiogenesis and Perfusion Imaging Using Multi-slice Spiral Computed Tomography for Breast Cancer

        Xu, Na,Lei, Zhen,Li, Xiao-Long,Zhang, Jun,Li, Chen,Feng, Guo-Quan,Li, Di-Nuo,Liu, Jing-Yi,Wei, Qiang,Bian, Ting-Ting,Zou, Tian-Yu Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.1

        Objectives: To explore the correlation between multi-slice spiral CT (MSCT) perfusion parameters and the expression of vascular endothelial growth factor (VEGF) as well as matrix metalloproteinase-2 (MMP-2) in breast cancer. Methods: Forty five breast cancer patients and 16 patients with benign breast tumor, both confirmed by pathology examination, were enrolled. All underwent MSCT perfusion imaging to obtain perfusion maps and data for parameters including blood flow (BF), blood volume (BV) and permeability surface (PS). Cancer patients did not receive treatment prior to surgery. The expression of VEGF and MMP-2 were examined with both immunohistochemistry and Western blotting. Results: The levels of VEGF and MMP-2 by immunohistochemistry were significantly higher in the breast cancer group (P < 0.01) than the benign tumor group. Relative OD values from Western blotting were also higher in cancer cases (P < 0.05). Similarly, the mean MSCT perfusion parameters (BF, BV, PS) were significantly higher in the breast cancer group (P < 0.01), BF and BV positively correlating with VEGF expression (r = 0.878 and 0.809 respectively, P < 0.01); PS and VEGF and MMP-2 expression were also positively correlated (r= 0.860, 0.786 respectively, P < 0.01). Conclusion: There is a correlation between breast cancer MSCT perfusion parameters and VEGF andMMP-2 expression, which might be useful for detection of breast lesions, qualitative diagnosis of breast cancer, and evaluation of breast cancer treatment.

      • Exosome-derived microRNA-29c Induces Apoptosis of BIU-87 Cells by Down Regulating BCL-2 and MCL-1

        Xu, Xiang-Dong,Wu, Xiao-Hou,Fan, Yan-Ru,Tan, Bing,Quan, Zhen,Luo, Chun-Li Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.8

        Background: Aberrant expression of the microRNA-29 family is associated with tumorigenesis and cancer progression. As transport carriers, tumor-derived exosomes are released into the extracellular space and regulate multiple functions of target cells. Thus, we assessed the possibility that exosomes could transport microRNA-29c as a carrier and correlations between microRNA-29c and apoptosis of bladder cancer cells. Materials and Methods: A total of 28 cancer and adjacent tissues were examined by immunohistochemistry to detect BCL-2 and MCL-1 expression. Disease was Ta-T1 in 12 patients, T2-T4 in 16, grade 1 in 8, 2 in 8 and 3 in 12. The expression of microRNA-29c in cancer tissues was detected by quantitative reverse transcriptase PCR (QRT-PCR). An adenovirus containing microRNA-29c was used to infect the BIU-87 human bladder cancer cell line. MicroRNA-29c in exosomes was measured by QRT-PCR. After BIU-87 cells were induced by exosomes-derived microRNA-29c, QRT-PCR was used to detect the level of microRNA-29c. Apoptosis was examined by flow cytometry and BCL-2 and MCL-1 mRNA expressions were assessed by reverse transcription-polymerase chain reaction. Western blotting was used to determine the protein expression of BCL-2 and MCL-1. Results: The expressions of BCL-2 and MCL-1 protein were remarkably increased in bladder carcinoma (p<0.05), but was found mainly in the basal and suprabasal layers in adjacent tissues. The expression of microRNA-29c in cancer tissues was negatively correlated with the BCL-2 and MCL-1. The expression level of microRNA-29c in exosomes and BIU-87 cells from the experiment group was higher than that in control groups (p<0.05). Exosome-derived microRNA-29c induced apoptosis (p<0.01). Although only BCL-2 was reduced at the mRNA level, both BCL-2 and MCL-1 were reduced at the protein level. Conclusions: Human bladder cancer cells infected by microRNA-29c adenovirus can transport microRNA-29c via exosomes. Moreover, exosome-derived microRNA29c induces apoptosis in bladder cancer cells by down-regulating BCL-2 and MCL-1.

      • KCI등재

        Taguchi Approach for Anti-heat Stress Prescription Compatibility in Mice Spleen Lymphocytes In Vitro

        Xiao-yu Zhu,Gui-lin Cheng,Feng-hua Liu,Jin Yu,Yu-jie Wang,Tong-quan Yu,Jian-qin Xu,Ming Wang 대한약학회 2011 Archives of Pharmacal Research Vol.34 No.7

        Heat stress (HS) may induce immunosuppression as well as inhibit the proliferation of lymphocytes. This study evaluated the effects on immune function of our prescription on splenic lymphocytes under HS as well as its compatibility. The effects of four herbal extracts from Agastache rugosa, Atractylodes lancea, Cortex Phellodendri, and Gypsum Fibrosum on heat treated splenic lymphocytes were investigated and the compatibility of the prescription was also explored by using the Taguchi method. This study revealed changes in proliferation by traditional Chinese medicines of splenic lymphocytes after HS. Proliferation in the HS group was significantly lower than the control group. Under HS, the effects of higher concentrations of Agastache rugosa (100 and 200 μg/mL), Atractylodes lancea (100 and 200 μg/mL), Cortex Phellodendri (50 and 100 μg/mL) and Gypsum Fibrosum (100 and 200 μg/mL) caused a significant increase on ConA/LPS-induced proliferation of lymphocytes than lower concentrations. We, therefore, conclude that the prescription of traditional Chinese medicines may recover splenic lymphocytes from the immunosuppression induced by HS. The Taguchi design, which allows rapid and high efficiency for the selection of the best conditions for our prescription on HS-treated splenic lymphocytes, demonstrated that Agastache rugosa (200 μg/mL), Atractylodes lancea (200 μg/mL), Cortex Phellodendri (100 μg/mL) and Gypsum Fibrosum (100 μg/mL)were the optimal conditions for the prescription. The validation experiment confirmed that our composition in optimum extraction conditions enhanced effects on ConA or LPS-stimulated lymphocytes under HS. The results showed that the Taguchi optimization approach is a suitable method for optimization of the composition of prescription.

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