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// Li-Fang Ye 1 , Ya-Ru Zheng 1 , Qing-Gang Zhang 1 , Jian-Wu Yu 1 and Li-Hong Wang 1 1 Department of Cardiovascular Sciences, Zhejiang Provincial People’s Hospital, Hangzhou, Zhejiang, China Correspondence to: Li-Hong Wang, email: wanglhnew@126.com Keywords: scavenger receptor class B type 1, polymorphism, lipid, sex Received: December 06, 2016 Accepted: August 26, 2017 Published: September 14, 2017 ABSTRACT Studies have shown that the scavenger receptor class B type 1 (SCARB1) rs5888 polymorphism impacts fasting blood lipid levels differently in men and women. A meta-analysis and statistical tests was therefore performed to determine the relationship between the rs5888 polymorphism and lipid levels in men and women. Twelve studies with 12,147 subjects were selected for this study. In a dominant model, the CT+TT genotype group had lower triglyceride levels than the CC group in men (standardized mean difference (SMD): –0.11; 95% confidence interval (CI): –0.21 to –0.02; P = 0.016; I 2 = 51.5%). No statistical differences were detected in women. Subgroup analysis of different racial groups revealed significant correlation between the SCARB1 rs5888 polymorphism and higher high-density lipoprotein cholesterol (HDL-C) levels (SMD: 0.15; 95% CI: 0.08 to 0.21; P ≤ 0.001; I 2 = 0%) and lower triglyceride levels (SMD: –0.16; 95% CI: –0.26 to –0.04; P = 0.013; I 2 = 60.6%) in non-Asian men. No evidence of heterogeneity was observed when eliminating outlier studies, and no publication bias was detected. This meta-analysis suggests the SCARB1 rs5888 polymorphism is associated with higher HDL-C and lower triglyceride levels in non-Asian men.

Background Air embolus penetrating into heart chamber as a complication during percutaneous radiofrequency catheter ablation has been infrequently reported. Case presentation A 55-year-old man with dextrocardia who suffered from abdominal pain was suspected to have multiple arterial thromboembolisms, which might have originated from left atrium thrombosis since he had atrial fibrillation. He received oral anticoagulant therapy and catheter ablation of the arrhythmia. During the ablation procedure, an iatrogenic aeroembolism penetrated into the left atrium due to improper operation. Ultimately, the entire air embolus was extracted from the patient, who was free of any aeroembolism events thereafter. Conclusions It is essential for an operator to pay full attention to all details of the procedure to avoid an aeroembolism during catheter ablation. In case of aeroembolism, removal by aspiration is an optimal and effective treatment. Electronic supplementary material The online version of this article (doi:10.1186/s12872-017-0581-7) contains supplementary material, which is available to authorized users.

High-efficiency and precision machining of complicated components can be realized by using metal-bonded CBN grinding wheel. However, the difficulty in dressing those superabrasive grinding wheels is one of the main obstructions to popularize its application in industry. Different from the traditional methods, the aim of the paper is to investigate the electro-discharge dressing of bronze-bonded CBN formed grinding wheel. Based on the analysis of electrical discharge parameters and grinding performance, the results show that electro-discharge dressing of CBN formed grinding wheel is feasible. With the increase of pulse duration, pulse voltage and pulse current, the dressing efficiency is increasing, more abrasive grains are protruding, but surface topography of grinding wheel is worsen. Therefore, grinding tests show that, in order to get the dressing quality better and keep the dressing efficiency higher, the bigger electrical discharge parameters are chosen for rough dressing process and the smaller ones are chosen for finishing process.

Hepatic fibrosis is a frequent feature of chronic hepatitis C virus (HCV) infection. Some evidence has suggested the potential role of silent information regulator 1 (SIRT1) in organ fibrosis. The aim of this study was to investigate the effect of HCV core protein on expression of SIRT1 of liver sinusoidal endothelial cell (LSEC) and function of LSEC. LSECs were co-cultured with HepG2 cells or HepG2 cells expressing HCV core protein and LSECs cultured alone were used as controls. After co-culture, the activity and expression levels of mRNA and protein of SIRT1 in LSEC were detected by a SIRT1 fluorometric assay kit, real time-PCR (RT-PCR), Western blot, respectively. The levels of adiponectin receptor 2 (AdipoR2), endothelial nitric oxide synthase (eNOS) and vascular endothelial growth factor (VEGF) were measured by Western blot. Cluster of differentiation 31 (CD31), CD14, and von Willebrand factor (vWf) of LSECs was performed by flow cytometry. The level of reactive oxygen species (ROS) was assayed. Malondialdehyde (MDA), superoxide dismutase (SOD), adiponectin, nitric oxide (NO), and endothelin-1 (ET-1) levels in the co-culture supernatant were measured. The co-culture supernatant was then used to cultivate LX-2 cells. The levels of α-smooth muscle actin (ASMA) and transforming growth factor-β1 (TGF-β1) protein in LX-2 cells were measured by Western blot. Compared with LSEC co-cultured with HepG2 cells group, in LSEC co-cultured with HepG2-core cells group, the activity and expression level of mRNA and protein of SIRT1 reduced; the level of adiponectin reduced and the expression level of AdipoR2 protein decreased; ROS levels increased; the expression level of eNOS, VEGF protein decreased; and the expression level of CD14 decreased; the expression level of vWf and CD31 increased; NO and SOD levels decreased; whereas ET-1 and MDA levels increased; the levels of ASMA and TGF-β1 protein in LX-2 cells increased. SIRT1 activator improved the above-mentioned changes. HCV core protein may down-regulate the activity and the expression of SIRT1 of LSEC, then decreasing synthesis of adiponectin and the expression of AdipoR2, thus inducing contraction of LSEC and hepatic sinusoidal capillarization and increasing oxidative stress, ultimately cause hepatic stellate cell (HSC) activation. Treatment with SIRT1 activator restored the function of LSEC and inhibited the activation of HSC.

Circular RNAs (circRNAs) are a novel type of endogenous noncoding RNA gaining research interest in recent years. Despite this increase in interest, the mechanism of circRNAs in the pathogenesis of multiple cardiovascular diseases, particularly myocardial fibrosis, is rarely reported. In the following study, the expression profiles and potential mechanisms of circRNAs in mice myocardial fibrosis models in vitro are investigated. Previous research examining circRNA expression profiles of diabetic db/db mice myocardium using circRNA microarray found 43 circRNAs were abnormally expressed, including 24 up-regulated circRNAs and 19 down-regulated circRNAs. Furthermore, circRNA_010567 was markedly up-regulated in diabetic mice myocardium and cardiac fibroblasts (CFs) treated with Ang II. Bioinformatics analysis predicted circRNA_010567, sponge miR-141 and miR-141 directly target TGF-β1, which was validated by dual-luciferase assay. Subsequently, functional experiments revealed circRNA_010567 silencing could up-regulate miR-141 and down-regulate TGF-β1 expression, and suppress fibrosis-associated protein resection in CFs, including Col I, Col III and α-SMA. Results demonstrate the circRNA_010567/miR-141/TGF-β1 axis plays an important regulatory role in the diabetic mice myocardial fibrosis model. The present study characterizes a new function of circRNA in the pathogenesis of myocardial fibrosis in a diabetic mouse model, providing novel insight for circRNA-miRNA-mRNA in cardiovascular disease.

Copper-tungsten alloy which is widely used in the field of EDM has high melting temperature and excellent electrical and thermal conductivity. Copper tungsten electrodes for electrical discharge dressing of metal-bond wheel were studied, and experiments were conducted to observe their wear performance in this paper. Orthogonal experiment was designed to explore the wear at the edge of and the bottom of electrode with the machining of holes. Thickness of the carbon layer, micro topography and experimental results were analyzed. Low current and big pulse duration can reduce the electrode wear rate. Although carbon on the electrode surface can be wiped out easily, wear rate of copper-tungsten electrode decreases with the increasing in thickness of the carbon at the initial phase. There are fewer cracks and residue presented on the machined surface by microscope.

YL10.2 and YF06 are ultrafine-grained cemented carbides, and grinding experiments were carried out with resin-bonded diamond grinding wheel. Based on measured grinding force, surface roughness and SEM topography, experimental results were analyzed; grinding forces and depth of grinding approach linear correlation; and the grinding force of YF06 is greater than that of YL10.2 in rough grinding, but the grinding force increases significantly if depth of cut is greater than a certain value in finish grinding. The trend of machined surface roughness looks like “V” type with the increasing of depth of cut; the material removal behavior of ultrafine-grained cemented carbides in grinding was observed; the ploughing and fragmentation exist simultaneously on the ground surface, and the dominated material removal behavior depends on the grinding parameters or chemical composition of workpiece.

Summary Background Steatosis and insulin resistance induced by hepatitis C virus (HCV) infection are, at least in part, critical factors for the progression of chronic hepatitis C (CHC) and can influence the outcome of antiviral treatment. Silent information regulator 1 (SIRT1) and adenosine monophosphate-activated protein kinase (AMPK) play a key role in the regulation of hepatic glucose and lipid metabolism. The aim of this study was to investigate the possible effect of HCV core protein on energy, glucose, and lipid metabolism of hepatocytes and expression of SIRT1 and AMPK. Methods HCV core protein expression plasmid was transfected into HepG2 cells. The level of reactive oxygen species (ROS) and values of NAD + /NADH and ATP/ADP were detected. Intracellular levels of triacylglycerol (TG), cholesterol, glucose uptake by hepatocytes, and glucose production were measured. The expression levels of mRNA and protein of SIRT1 and AMPK were detected. The mRNA levels of SIRT1 and AMPK downstream glucose and lipid metabolism genes were measured. Results In HepG2 cells expressing HCV core protein, the level of ROS increased, the value of NAD + /NADH decreased, the activity and expression levels of mRNA and protein of SIRT1 and AMPK decreased, glucose uptake and its regulator gene GLUT2 mRNA levels decreased, glucose production and its regulator genes PEPCK and G6Pase mRNA levels increased, intracellular TG and cholesterol contents and their regulator gene (SREBP-1c, FAS, ACC, HMGR, and HMGS) mRNA levels increased, the glycolytic gene GK and fatty acid oxidation genes PPARα and CPT1A mRNA levels decreased. Conclusions HCV core protein induces alterations in cellular redox state (decrease in the NAD + /NADH ratio), which could influence the activity of SIRT1 and secondarily AMPK, then change the expression profile of glucose and lipid metabolism-related genes, thereby causing metabolism disorders of hepatocytes.

Aim Hepatic steatosis is an important histopathological feature of chronic hepatitis C virus (HCV) infection. Silent information regulator 1 (SIRT1) plays key role in regulation of hepatic lipid metabolism. We investigated the possible effect of HCV replication on lipid metabolism of hepatocytes and expression of SIRT1 using Huh-7.5 cells harboring HCV replicon. Methods The level of reactive oxygen species (ROS) and malondialdehyde (MDA), the activity of superoxide dismutase (SOD), and the value of nicotinamide adenine dinucleotide (NAD+)/NADH was detected. The level of triacylglycerol (TG), total cholesterol (TC) and fatty acid β-oxidation rate was detected. The activity and expression levels of SIRT1 and expression of its downstream lipid-metabolism genes were measured. Results In replicon cells, the level of ROS and MDA increased, SOD activity and the value of NAD+/NADH decreased, then the activity and expression level of mRNA and protein of SIRT1 reduced. Inhibition of SIRT1 decreased phosphorylation of forkhead box O1 (FoxO1), which not only upregulated SREBP-1c, FAS, ACC, SREBP-2, HMGR and HMGS genes and increased fatty acid synthesis; but also downregulated PPAR-α and CPT1A genes and decreased fatty acid β-oxidation. Interferon treatment restored aforementioned changes. SIRT1 activator improved lipid metabolism disorders by an increase in fatty acid β-oxidation and a decrease in TG and TC synthesis and inhibited HCV replication. Conclusion HCV replication decreasing NAD+/NADH ratio may downregulate the activity and the expression of SIRT1, then change the expression profile of lipid metabolism-related genes, thereby cause lipid metabolism disorders of hepatocytes and promote HCV replication. Treatment with SIRT1 activator ameliorates lipid metabolic disorders and inhibits HCV replication.

Glucose metabolism disorders including insulin resistance (IR) and type 2 diabetes are frequent and important cofactors of chronic hepatitis C (CHC). Silent information regulator 1 (SIRT1) plays a key role in the regulation of hepatic glucose metabolism. We investigated the possible effect of HCV replication on glucose metabolism of hepatocytes and expression of SIRT1 using Huh-7.5 cells harboring the HCV replicon.The level of reactive oxygen species (ROS) and value of NAD(+)/NADH and ATP/ADP were detected. Glucose uptake by hepatocytes and glucose production were measured. The activity and expression levels of SIRT1 and expression of its downstream glucose-metabolism genes were measured.In replicon cells, the level of ROS increased and the value of nicotinamide adenine dinucleotide (NAD(+))/NADH decreased, then the activity and expression level of mRNA and protein of SIRT1 decreased. Inhibition of SIRT1 not only increased insulin receptor substrate-1 phosphorylation and decreased Akt phosphorylation, inhibited cell surface expression of glucose transporter 2 and suppressed cellular glucose uptake, but it also decreased phosphorylation of forkhead box O1, then upregulated phosphoenolpyruvate carboxykinase and glucose 6-phosphatase genes and downregulated the glucokinase gene, thus promoting glucose production. Interferon treatment restored the aforementioned changes. SIRT1 activator improved glucose metabolism disorders by an increase in glucose uptake and a decrease in glucose production, and it inhibited HCV replication.HCV replication decreasing the NAD(+)/NADH ratio may downregulate the activity and expression of SIRT1, then change the expression profile of glucose metabolism-related genes, thereby causing glucose metabolism disorders of hepatocytes and promoting HCV replication. Treatment with SIRT1 activator improves glucose metabolic disorders and inhibits HCV replication, suggesting that restoration of SIRT1 activity may be a promising new therapeutic approach for CHC patients with IR.

Recent studies indicated that Gene Associated with Retinoid-IFN-Induced Mortality 19 (GRIM-19), a newly discovered mitochondria-related protein, can regulate mitochondrial function and modulate cell viability possibly via interacting with STAT3 signal. In the present study we sought to test: 1) whether GRIM-19 is involved in high glucose (HG) induced altered cell metabolism in both cancer and cardiac cells, 2) whether GRIM-19/STAT3 signaling pathway plays a role in HG induced biological effects, especially whether AMPK activity could be involved. Our data showed that HG enhanced cell proliferation of both HeLa and H9C2 cells, which was closely associated with down-regulated GRIM-19 expression and increased phosphorylated STAT3 level. We showed that GRIM-19 knock-down alone in normal glucose cultured cells can also result in an increase in phosphorylated STAT3 level and enhanced proliferation capability, whereas GRIM-19 over-expression can abolished HG induced STAT3 activation and enhanced cell proliferation. Importantly, both down-regulated or over-expression of GRIM-19 increased lactate production in both HeLa and H9C2 cells. The activated STAT3 was responsible for increased cell proliferation as either AG-490, an inhibitor of JAK2, or siRNA targeting STAT3 can attenuate cell proliferation increased by HG. In addition, HG increased lactate acid levels in HeLa cells, which was also observed when GRIM-19 was genetically manipulated. However, HG did not affect the lactate levels in H9C2 cells. Of note, over-expression of GRIM-19 and silencing of STAT3 both increased lactate production in H9C2 cells. As expected, HG resulted in significant decreases in phosphorylated AMPKα levels in H9C2 cells, but not in HeLa cells. Interestingy, activation of AMPKα by metformin was associated with a reversal of the suppressed GRIM-19 expression in H9C2 cells, the fold of changes in GRIM-19 expression by metformin were much less in HeLa cells. Metformin did not affect the phosphorylated STAT3 lelvels, however, decreased its levels in H9C2, especially in the setting of HG culture. Not like HG alone which resulted in no changes in lactate acid in H9C2 cells, metformin can increase lactate acid levels in H9C2 cells. Increased lactate induced by metformin was also observed in HeLa cells.

Optical glass is widely used as the most important material in optical field in recent years. Glass molding press (GMP) has been employed as a promising technique to manufacture optical components in mass production. Heating time and annealing time are the key factors which influence the production cycle. In this paper, an effective method of improving the heating or the annealing effectiveness is to increase the area exposed to the cooling or hot nitrogen by means of adding slots. In the same condition, four models with different slots were built. Based on the theoretical analysis of glass heating and annealing property in the molding process, finite element simulation was carried out. The results showed that the model with slots may decrease the heating and annealing time.

Based on the lapping principle of spiral bevel gears and hypoid gears, this paper focuses on a new automatic backlash adjustment method for lapping process, which includes on-line detection and measurement of backlash, automatic backlash control and software etc. The experimental results shows that this on-line automatic backlash control method is efficiency and stable in lapping process, and it can improve gear surface finishing and reduce transmission noise apparently.

An extracting method of normal residual error from a ground profile was proposed in this paper. Original measurement data was re-processed for obtaining an actual ground profile in an on-machine contact measurement system. The robust Gaussian regression filtering and NURBS fitting methods were employed to filter and fit these discrete data for getting the accurate realistic ground profile. By utilizing iterative partitioning algorithm, the normal residual error could be accurately obtained between the actual ground profile and the ideal one. Measurement data achieved from grinding experiment of aspheric mould were dealt with. After form error compensation grinding, the difference between normal residual error and original reached 40 nm in stead of initially 140 nm.

Silicone oil based magnetic compound fluid was prepared to polishing stainless steel in this paper. The new fluid consists of nano-sized magnetite particle, micro-sized diamonds, micro-sized iron particle and α-cellulose. The characteristics of the fluid were analyzed. The length and quality of the magnetic cluster in the compound fluid was observed under a magnetic field. Polishing experiment of stainless steel was conducted using the silicone oil based magnetic compound fluid on an inclined polishing finishing device. The micro morphology of the stainless steel’s surface was measured. The results showed the surface quality was improved remarkably and the final roughness of the surface was Ra (Average roughness) 0.020μm.

Glass molding is a high-volume fabrication method for producing optical components. Non-isothermal glass molding press (NGM) was proposed to fabricate optical glass, and its characteristics were studied by finite element method (FEM) simulation. The coupled thermo-mechanical analysis was carried out to analyze the key factors such as temperature distribution, stress distribution and strain distribution. The non-isothermal and isothermal glass molding (IGM) was studied, and optimal temperature match between glass and mold was obtained.

Stainless steel; Aspheric mould; Ultra-precision turning; Magnetorheological polishing Abstract. The ultra precision turning and the inclined-axis type of magnetorheological polishing were introduced for the small aspheric mould of stainless steel. The method was based on the principle of two kinds of processing methods, and the processing feature of stainless steel material. Firstly, the ultra-precision turning was employed to shape aspheric surface rapidly and obtain a relatively good surface. And then, the inclined-axis type of magnetorheological polishing as the final finishing was used to decrease sub-surface damage to obtain better precision. Several of experiments were carried out, the experimental results show that surface roughness can be achieved for Ra 0.0073μm.

In traditional manufacture of grinding wheel, a key problem is the randomly arrangement of the diamond abrasives, which results in randomly distribution of surface roughness. In this paper, through controlling the magnetic field during the forming process of the grinding wheel, arrangement of diamond abrasives is orderly to obtain a more orderly surface roughness. The forming process of diamond fine grinding wheel is studied under magnetic field controlling. The grinding experiment for aspherical mold was carried out on the tungsten carbide YG8 and the surface quality after grinding was also analyzed

Glass lens molding is a high-volume fabrication method for producing optical components. In this paper, combined with the orthogonal test method and finite element method (FEM) simulation, the coupled thermo-mechanical analysis was carried out to analyze the key process factors. In order to reduce the testing time, an orthogonal test with three sets of level factors and three parameters is conducted to obtain the optimal molding process parameters. The result shows that the most significant parameter is molding velocity, the other effect parameters are molding temperature and friction coefficient. According to the previous analysis of orthogonal experiment, it is shown that the best optimal finishing process parameters were A2B1C1.

SummaryObjectivesThe relationship between patient sex and the effectiveness of peginterferon alpha-2a and ribavirin treatment in chronic hepatitis C (CHC) patients remains unclear. The aim of this study was to investigate the impact of sex on virologic responses rates in genotype 1 CHC patients.MethodsA matched retrospective cohort study of 630 genotype 1 patients treated with peginterferon and ribavirin derived from our hospital database was conducted. These patients were divided into three groups according to age: patients aged

Based on the magnetic field controlling principle, a new manufacturing method and experimental research of fine grain diamond grinding wheel were introduced. The magnetic particles could form spatial chain structures under magnetic field which can make abrasives distributed uniformly within the mold. Therefore, small surface roughness can be obtained when grinding. The manufacturing and dressing of fine grain diamond grinding wheel based on magnetic field controlling (acronym FGDWMC) were introduced. The comparison grinding tests between the magnetic field controlling and nonmagnetic field controlling of wheels were studied. The grinding experiment result showed that the surface roughness was better after being machined by FGDWMC, and it was improved by about 20nm.

With the rapid development of opto-electronics communications, optics, aerospace and other industries, ultra-precision aspheric glass lenses are widely used in middle/high-grade optical opponent because of its high resolution and imaging quality. To achieve ultra-precision molding pressing of micro-lens, ultra-precision mold must be fabricated firstly. In this paper, some key new technologies were proposed for fabricating ultra-precision mold of small-size aspheric optical lens. A method of finite element simulation was employed to predict mould pressing process of the glass lens for correcting molds and improving the formation efficiency. An ultra-precision inclined-axis grinding and error compensation technology was also used to improve form accuracy of micro lens mold.

The machining characteristics of cemented carbide YG8 under high speed grinding conditions are reported in this paper. The experimental investigation focused on the grinding force, surface roughness and surface characteristics influenced by various wheel speeds, feed rates and depths of cut. Surface roughness was slightly improved by increasing of wheel speed, and the increase in hmax generated bigger grinding force and decreased specific energy, which could be explained by material removal mode and SEM micrographs of surface. The results revealed that high machining efficiency was achieved and relatively good surface roughness was obtained simultaneously.

Through establishing the mathematical models of velocity and grinding force to optimize the installation angle with inclined axis grinding technology, the spherical surface of the ultra-hard alloy material was ground by formed electroplated diamond wheel. After analyzing the abrasion of grinding wheel, the results show that the inclined axis grinding technology of the formed grinding wheel can avoid the rotation dead spots of grinding wheel, and can make the grinding wheel surface contacted with work-piece fully which could make the worn more evenly. Finally, it obtains a surface in a high quality with the surface roughness of Ra is 12.88nm, and the form accuracy of PV is 124nm.

Ultrasonic assisted electrical discharge machining (USEDM) is one of hybrid machining methods based on the EDM process. The effects of ultrasonic waves on EDM process were analyzed and the experimental investigation of productivity of steel induced by USEDM was reported. Results indicated that ultrasonic waves and cavitation played an important role in improving the flushing and machining efficiency during USEDM. And the material removal rate of EDM assisted by ultrasonic waves was improved greatly.

Objective: Fulminant hepatitis B is a clinical syndrome that results from massive necrosis of liver cells leading to the development of hepatic encephalopathy. The aim of this study was to evaluate the efficacy of lamivudine in patients with fulminant hepatitis B and study the prognostic factors. Methods: A matched retrospective cohort study using data on fulminant hepatitis B patients derived from our hospital database was conducted. Forty patients receiving lamivudine treatment were selected into the lamivudine treatment group with another 40 without lamivudine treatment studied as control. They were matched for sex, age and HBeAg status with lamivudine treatment group. The mortality of patients in two groups was compared. The influential factors on the mortality were studied by Cox proportional hazards model. Results: The mortality of patients in the lamivudine group (n=38) was significantly lower than that of the control group (n=39) (63.2 vs. 84.6%; χ2=4.609, P=0.032). For patients without systemic inflammatory response syndrome (SIRS), the mortality of patients in the lamivudine group (n=25) was significantly lower than that of the control group (n=26) (52.0 vs. 80.8%; χ2=4.747, P=0.029). In multivariate Cox proportional hazards analyses, for patients without SIRS, age (P=0.037), ratio of total to direct bilirubin (P=0.008), treatment method (P=0.005) and the decline of hepatitis B virus (HBV) DNA load during therapy (P=0.019) were independent predictors of prognosis. Conclusions: Treatment with lamivudine significantly decreases the mortality of fulminant hepatitis B patients without SIRS, and a rapid decline of HBV DNA load is one of the good predictors for the treatment outcome.

This paper reported a deterministic method to predict geometrical interferences between grinding wheel and workpiece on ultra-precision grinding for micro aspherical lens mould. An inclined axis grinding mode controlled by B axis is considered and investigated. For avoiding the interference between the grinding wheel and the workpiece, the relationship of the radius of the grinding wheel should be analyzed in the grinding process. In this paper, a geometrical mathematical model for avoiding interferences between grinding wheel and workpiece is built up, and three interference conditions are analyzed. The maximum diameter of the cylindrical grinding wheel is computed and obtained for grinding axisymmetric aspheric surface.

Focusing on the characteristic of hard-to-grinding for viscous materials, such as titanium alloy, systemic process experiments were done about grinding viscous materials, such as TC4 titanium alloy, under the high efficiency deep grinding (HEDG). Based on the analysis to the changing and characteristic of unit area grinding force F' with maximum undeformed chip thickness hmax and equivlent cutting thickness aeq , this paper discussed the changing of its material removal mode and analyzed the changing and characteristic of grinding force ratio N, specific grinding energy es with corresponding parameters further. Then, it was analyzed about the consumption of grinding power on the process of HEDG for TC4 titanium alloy. The experiment results reveal that application of HEDG can improve machining efficiency of grinding viscous materials.

This paper focuses on experimental investigation on high speed grinding of 40 Cr steel with vitrified CBN grinding wheel, the effect of grinding process parameters, such as grinding speed, depth of cut, and feed rate, on the grinding force and surface roughness are analyzed The experimental results reveal that the grinding force decreases with higher grinding speed and increases with the addition of depth of cut or feed rate, and the surface roughness is satisfactory in high speed grinding.

Background and Aims: Chronic hepatitis B virus (HBV) infection is a major global health issue, and the prognosis of patients with HBV-associated acute-on-chronic hepatic failure (ACLF) is extremely poor. In this study, the efficacy of lamivudine was investigated in patients with ACLF. The effects of HBV DNA load and its related factors on the prognosis were also further explored. Methods: A matched retrospective cohort study using data on ACLF patients derived from our hospital database was conducted. One hundred and thirty patients receiving lamivudine were selected into the lamivudine treatment group with another 130 without lamivudine treatment studied as control. They were matched for sex, age and imaging finding with the lamivudine treatment group. All the patients were followed up for 3 months and the survival rates were compared. The influential factors on the mortality were studied by the Cox proportional hazards model. Results: The cumulative survival rates of patients in the lamivudine group were higher than those of the control group (χ2 = 9.50, P = 0.0021). The mortality of patients in the high virus load group (71/95, 74.7%) was higher than that of those in the low virus load group (15/29, 51.7%) (χ2 = 5.536, P = 0.019). For patients with a Model for End-Stage Liver Disease (MELD) score of 20–30 by week 4, the mortality of those with HBV DNA that was undetectable or declined for more than 2 log10 (2/12, 16.7%; 18/40, 45.0%) was lower than that of those with a less than 2 log10 decline (18/23, 78.3%) (χ2 = 10.106, P = 0.001). In the Cox proportional hazards model, for patients with a MELD score of 20–30, treatment method (P = 0.002), pretreatment HBV DNA load (P = 0.007) and decline of HBV DNA load during therapy (P = 0.003) were independent predictors; for those with a MELD score of above 30, MELD score (P = 0.008) was the only independent predictor. Conclusion: Lamivudine can significantly decrease the 3-month mortality of patients with a MELD score of 20–30, and a low pretreatment viral load and rapid decline of HBV DNA load are good predictors for the outcome of the treatment.

Severe acute hepatitis B is a rapid deterioration of liver function, which carries a high mortality rate. The aim of this study is to evaluate the efficacy of lamivudine in patients with severe acute hepatitis B. In this study, 80 patients with severe acute hepatitis B were randomly divided into lamivudine and the control group. For the two groups, we compared HBsAg, HBeAg seroconversion rates, serum HBV DNA-negative rate, biochemical indicators, the incidence of liver failure, and mortality. The influential factors on the mortality were studied by Cox proportional hazards model. The improvement in serum TBiL, INR, and HBV DNA levels of the lamivudine group was significantly greater than that of the control group. The mortality of lamivudine group (7.5%, 3/40) was significantly lower than that of the control group (25.0%, 10/40) (p = 0.034). The incidence of liver failure (8.7%, 2/23) of patients receiving lamivudine within a week was significantly lower than that (35.3%, 6/17) of those who received it after a week (p = 0.038). In multivariate Cox proportional hazards analyses, age (p = 0.043), ratio of total to direct bilirubin (p = 0.009), treatment method (p = 0.006), and the decline of HBV DNA load during therapy (p = 0.017) were independent predictors of mortality. The HBsAg seroconversion rates (62.5%, 25/40) and HBeAg seroconversion rates (63.6%, 21/33) of the lamivudine group were significantly lower than those (85.0%, 34/40), (87.5%, 28/32) of the control group (p = 0.022, 0.026). Early treatment with lamivudine leads to a greater decrease in HBV DNA level, better clinical improvement and mortality improvement in patients with severe acute hepatitis B, but with a lower seroconversion rate. A rapid decline of HBV DNA load is a good predictor for the treatment outcome.

OBJECTIVE To study the virological features of patients coinfected with hepatitis B virus (HBV) and hepatitis C virus (HCV) and the efficacy of combination therapy with peginterferon alpha-2a and ribavirin in these patients. METHODS The epidemiological and virological data of 50 patients coinfected with HBV and HCV were analysed. The virological response rates of patients treated with peginterferon alpha-2a and ribavirin between the HBV and HCV coinfection group and the HCV monoinfection group were compared. RESULTS HCV-dominant virus strains accounted for 92.0% of the 50 coinfected individuals, and HCV- and HBV-dominant virus strains accounted for the remaining 8.0%. The HBV DNA level of the patients coinfected with HBV and HCV was 4.6+/-0.9 log(10) copies/ml, which was significantly lower than that in the HBV monoinfection group (5.9+/-1.2 log(10) copies/ml) (t=5.964, P

Focusing on the characteristic of hard-to-grind for titanium alloy, experiments were conducted about grinding TC4 titanium alloy under high speed deep grinding (HSDG) condition. The changing of grinding force per unit area with maximum undeformed chip thickness hmax and equivalent cutting thickness aeq are analyzed in this paper. The effect of maximum undeformed chip thickness hmax and specific material removal rate Zw' on specific grinding energy es, material removal mechanism and consumption of grinding power in HSDG process are also discussed. The experiment results reveal that application of HSDG can improve machining efficiency of grinding TC4.

Titanium alloy is a kind of typical difficult-to-machine materials. In this study, the surface integrity of titanium alloy Ti-6Al-4V machined by electrical discharge machining (EDM) method are experimentally investigated and analyzed in term of surface roughness, SEM micrographs and microcracks. Effect of discharge energy and material properties on surface integrity are presented in this paper.

According to the sharp rheological characteristics of magnetorheological fluid in the magnetic field, the principle and mechanism of magnetorheological finishing is analyzed. Based on the Preston equation, the Reynolds equation and its boundary conditions, the two-dimensional material removal model is built and simulated. Furthermore, a series of MRF experiments are carried out, and the influence of the immersed depth and material kinds on material removal rate are clarified respectively. The experimental results are compared with the modeling results of material removal rate to confirm the mechanistic model validity.

To investigate the role of the host-encoded silent information regulator 1 (SIRT1) on hepatocytes' lipid metabolism under conditions of hepatitis C virus (HCV) infection and assess its potential effects on virus replication in vitro.The Huh-7.5 human hepatocyte cell line was used as the control group and Huh-7.5 cells stably expressing the HCV replicon (Huh7.5-HCV) were used as the experimental group. Effects of interferon (IFN) treatment and activation of SIRT1 by resveratrol were also observed. The mRNA and protein expression levels of SIRT1 were detected by real time (q)PCR and western blotting. Effects on SIRT1 protein activity were tested by measuring the levels of reactive oxygen species (ROS) and the nicotinamide adenine dinucleotide (NAD+)/beta-nicotinamide adenine dinucleotide, reduced (NADH) by flow cytometry and chromatometry, and the levels of triacylglycerol (TG), total cholesterol (TC), and fatty acid beta oxidation rate by enzymatic analysis and liquid scintillation counting. Effects on mRNA expression of SIRT1 downstream lipid-metabolism genes were measured by qPCR.The Huh7.5-HCV cells had a significantly higher level of ROS (3.8+/-0.5 vs. Huh-7.5: 1.0+/-0.2; t = 12.736, P less than 0.01) but significantly lower levels of NAD+/NADH (0.03+/-0.01 vs. 0.12+/-0.03; t = 6.971, P less than 0.01), SIRT1 activity (0.3+/-0.1 vs. 1.0+/-0.2, 0.9+/-0.2, F = 6.766, P less than 0.01), SIRT1 mRNA (0.4+/-0.1 vs. 1.0+/-0.3, 0.9+/-0.2, F = 5.864, P less than 0.01), and SIRT1 protein (0.3+/-0.1 vs. 0.8+/-0.2, 0.9+/-0.2, F = 5.419, P less than 0.01). The lower levels of SIRT1 in Huh7.5-HCV cells accompanied decreased phosphorylation of the forkhead box O1 (FoxO1), which not only up-regulated the downstream genes of SREBP-1c, FAS, ACC, SREBP-2, HMGR and HMGS (which increased fatty acid synthesis) but also down-regulated the downstream genes of PPAR and CPT1A genes (which decreased fatty acid beta oxidation). IFN treatment restored all of the aforementioned changes. Resveratrol-induced SIRT activation improved the perturbations in lipid metabolism pathways, as evidenced by an increase in fatty acid beta oxidation and a decrease in TG and TC synthesis, as well as inhibited HCV replication.HCV may decrease the NAD+/NADH ratio in hepatocytes, leading to a down-regulation of SIRT1 activity and expression and perturbing the downstream expression profile of lipid metabolism-related factors, ultimately causing lipid metabolism disorders and establishing a permissive intracellular environment for HCV replication.

Summary Background Insulin resistance is highly prevalent in patients with chronic hepatitis C (CHC) and to some extent accounts for fibrosis and reducing viral eradication. Activated cannabinoid 1 receptor (CB1R) signaling has been implicated in the development of phenotypes associated with insulin resistance and steatosis. We investigated the role of the endocannabinoid system in glucose metabolism disorders induced by hepatitis C virus (HCV) replication. Methods Human hepatic stellate cells (HSC; LX-2 cells) were co-cultured with Huh-7.5 cells or Huh-7.5 cells harboring HCV replicon (replicon cells). Endocannabinoid levels were then measured by liquid chromatography/mass spectrometry. The expression of CB1R and its downstream glucose metabolism genes in hepatocytes were determined by real-time PCR and Western blot. Glucose uptake by hepatocytes and glucose production were measured. Glucose metabolism tests and measurements of HCV RNA levels and nonstructural protein 5A (NS5A) levels were taken after treatment with CB1R agonist arachidonyl-2-chloroethanolamide (ACEA) or antagonist AM251. Results Compared to the co-culture with Huh-7.5 cells, the level of 2-arachidonoylglycerol (2-AG) and the CB1R mRNA and protein levels increased in the co-culture of LX-2 cells with replicon cells. The activation of CB1R decreased AMP-activated protein kinase (AMPK) phosphorylation, inhibited cell surface expression of glucose transporter 2 (GLUT2), and suppressed cellular glucose uptake; furthermore, it increased cyclic AMP response element-binding protein H (CREBH), then up-regulated phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase (G6Pase) genes and down-regulated the glucokinase (GK) gene, thus promoting glucose production. Interferon treatment restored the aforementioned changes. CB1R antagonist improved glucose metabolism disorders by an increase in glucose uptake and a decrease in glucose production, and inhibited HCV replication. Conclusions HCV replication may not only increase the 2-AG content, but may also up-regulate the expression of CB1R of hepatocytes, then change the expression profile of glucose metabolism-related genes, thereby causing glucose metabolism disorders of hepatocytes and promoting HCV replication. Treatment with CB1R antagonist improved glucose metabolism disorders and inhibited viral genome replication.

Hepatic steatosis is an important histopathological feature of chronic hepatitis C virus (HCV) infection. Silent information regulator 1 (SIRT1) plays key role in regulation of hepatic lipid metabolism. We investigated the possible effect of HCV replication on lipid metabolism of hepatocytes and expression of SIRT1 using Huh-7.5 cells harboring HCV replicon.The level of reactive oxygen species (ROS) and malondialdehyde (MDA), the activity of superoxide dismutase (SOD), and the value of nicotinamide adenine dinucleotide (NAD(+) )/NADH was detected. The level of triacylglycerol (TG), total cholesterol (TC) and fatty acid β-oxidation rate was detected. The activity and expression levels of SIRT1 and expression of its downstream lipid-metabolism genes were measured.In replicon cells, the level of ROS and MDA increased, SOD activity and the value of NAD(+) /NADH decreased, then the activity and expression level of mRNA and protein of SIRT1 reduced. Inhibition of SIRT1 decreased phosphorylation of forkhead box O1 (FoxO1), which not only upregulated SREBP-1c, FAS, ACC, SREBP-2, HMGR and HMGS genes and increased fatty acid synthesis; but also downregulated PPAR-α and CPT1A genes and decreased fatty acid β-oxidation. Interferon treatment restored aforementioned changes. SIRT1 activator improved lipid metabolism disorders by an increase in fatty acid β-oxidation and a decrease in TG and TC synthesis and inhibited HCV replication.HCV replication decreasing NAD(+) /NADH ratio may downregulate the activity and the expression of SIRT1, then change the expression profile of lipid metabolism-related genes, thereby cause lipid metabolism disorders of hepatocytes and promote HCV replication. Treatment with SIRT1 activator ameliorates lipid metabolic disorders and inhibits HCV replication.

To explore the feasibility and methodology of radiofrequency catheter ablation (RFCA) guided by 3D navigation system (Ensite-NavX) for right atrioventricular accessory pathway.Thirty-three cases of right accessory pathway atrioventricular reentrant tachycardia including 16 cases in right free wall, 3 in right middle septum, 14 in right posterior septum; 23 cases of dominant accessory pathway and 10 cases of concealed were treated by RFCA guided by NavX navigation. NavX navigation modeling method or spatial localization method was exploited to locate target positioning.All patients were successfully ablated without serious complications. Among them, 25 cases were operated without exposure to X-ray, 7 patients were exposed for several seconds to verify catheter position, 1 case in right free wall was ablated under X-ray combined with Swartz sheath ablation.Nonfluoroscopy or less fluoroscopy RFCA for right atrioventricular accessory pathway with Ensite-NavX is safe and feasible, modeling or spatial orientation method are helpful to locate the ablation target positioning.

To investigate the correlation between neutropenia (ANC) incidence and infection during treatment with peginterferon alfa and ribavirin for chronic hepatitis C.A retrospective cohort study of 399 patients treated with peginterferon and ribavirin derived from database of Department of Infectious Diseases, the Second Affiliated Hospital, Harbin Medical University was conducted. The incidence of infections and their relation with ANC were investigated. Potential risk factors for infection were identified by multivariate analysis.During treatment, neutropenia (ANC1.50 × 10(9)/L) occurred in 251 patients. Among which, mild neutropenia [ANC: (0.75 -1.50) × 10(9)/L], moderate neutropenia [ANC: (0.50 - 0.75) × 10(9)/L] and severe neutropenia (ANC0.50 × 10(9)/L) occurred in 132 patients, 103 patients and 16 patients, respectively. A total of 80 infections (20.1%) occurred, among which, 14 infections were defined as severe. There was no significant difference in infection rate between patients with and without neutropenia (19.9%, 50/251 vs 20.3%, 50/251; χ(2) = 0.007, P = 0.933). There was no significant difference in infection rate between patients with and without peginterferon dose reduction (21.5%, 31/144 vs 19.2%, 49/255; χ(2) = 0.307, P = 0.580). In multivariate logistic regression analysis, the independent factors associated with infection were age (P = 0.021), diabetes (P = 0.004) and cirrhosis (P = 0.012).Infections during treatment with peginterferon alfa and ribavirin for chronic hepatitis C are irrelevant to neutropenia. The independent factors associated with infection are age, diabetes and cirrhosis.

To investigate the impact of age and sex on virologic responses rates to peginterferon alfa-2a and ribavirin treatment in patients with chronic hepatitis C.The medical records of 449 chronic hepatitis C patients, treated with peginterferon and ribavirin in Department of Infectious Diseases, the Second Affiliated Hospital, Harbin Medical University, were retrospectively analyzed. These patients were divided into three groups according to age: patients40 years (n = 131), patients 40 - 50 years (n = 131) and patients50 years (n = 187). The virologic response rates, the incidences of side events, and the rates of patients receiving ≥ 80% of planned peginterferon alfa-2a or ribavirin dose were compared between male and female patients in the three groups. The influential factors on sustained virologic response (SVR) of patients were studied by multivariate analysis.For genotype 1, in patients40 years group, the SVR rate of female was significantly higher than that of male (75.0%, 30/40 vs 54.0%, 27/50; P0.05); in patients 40-50 years group, there was no significant difference in the SVR rate between male and female (51.0%, 25/49 vs 53.7%, 22/41; P0.05); in patients50 years group, the SVR rate of female was significantly lower than that of male (31.1%, 19/61 vs 50.7%, 34/67; P0.05). For genotype 2, there were no significant differences in virologic response rates between male and female in the three groups. The incidence of adverse events of patients aged40 years group, 40 - 50 years group,50 years group, were 51.1% (67/131), 51.1% (67/131), and 70.6% (132/187), respectively, and the incidence of adverse events of patients aged50 years was significantly higher than those of other groups (P0.001). For genotype 1, in patients50 years group, the rate of patients receiving ≥ 80% of planned ribavirin dose of female was significantly lower than that of male (42.6%, 26/61 vs 62.7%, 42/67; P0.05). In multivariate analysis, the independent factors associated with SVR of patients aged50 years were sex (P = 0.013), genotypes (P = 0.002), cirrhosis (P = 0.004), ≥ 80% of planned ribavirin dose (P = 0.008) and presence of rapid virologic response (RVR) (P = 0.001).For genotype 1 patients, in patients40 years group the SVR rate of female is higher than that of male; in patients 40 - 50 years group, male and female share similar SVR rates; in patients50 years group the SVR rate of female is lower than that of male. Age and sex has no impact on virologic responses rates for genotype 2 patients.

Glass molding press (GMP) is a kind of mass production method to manufacture infrared aspheric lenses made from chalcogenide. However, it's hard to determine the molding parameters during the GMP process because the lens forming is conducted under the high-temperature conditions. In this paper, the finite element method (FEM) is used to simulate the GMP process based on the general Maxwell viscoelastic model and thermo-rheologically simple property. During the simulation, 2-D axisymmetric FEM model is constructed according to the different pressing velocities and friction coefficients, which change from 0.01mm/s to 0.5mm/s and from 0.01 to 0.2, respectively. To improve the simulation accuracy, the heating and pressing steps are separate and the heated result is taken as the pre-state of pressing step. The final results show that the best molding conditions are 0.1~0.2mm/s in velocity and 0.1~0.15 in friction coefficient for the infrared aspheric lenses made from chalcogenide of Ge33As12Se55.

To establish a nested real-time quantitative polymerase chain reaction (PCR) assay for detection of hepatitis B virus covalently closed circular DNA in PBMC( peripheral blood monocyte) and MMNC (marrow monocyte).Based on the structural differences between HBVcccDNA and HBV rcDNA, two pairs of specific primers spanned the gap of the positive and negative chains and a specific TaqMan probe situated downstream were designed. To remove rcDNA, cccDNA was processed by Mung Bean Nuclease,and then amplified by nested real-time quantitative PCR using a pair of outer primers and a pair of inner primers. According to the standard preparation, cccDNA levels of specimen were calculated.We have established a nested real-time fluorescent quantitative PCR method for HBV cccDNA successfully, and the linear range is from 5.0 x 10(2) to 3. 9 x 10(7) copies per milliliter. Of the 25 PBMC samples and 7 MMNC samples of the chronic hepatitis B or liver cirrhosis patients, 3 MMNC samples and 9 PBMC samples were HBV cccDNA positive, while all of the 21 healthy donator blood PBMC samples were negative.The nested real-time fluorescent quantitative PCR method may be applied to detect HBVcccDNA level in PBMC and MMNC. HBVcccDNA can be detected in PBMC and MMNC.

To compare the efficacy and safety between cryoablation (Cryo) and radiofrequency (RF) ablation for treating patients with atrioventricular nodal reentrant tachycardia (AVNRT).Patients with AVNRT (n = 304) were divided into Cryo group (n = 67) and RF group (n = 237). The procedure success rate, complete slow pathway block rate, atrioventricular block rate and relapse rate were compared between two groups.There was no statistically difference between 2 groups in the success rate (Cryo group 98.5% vs RF group 97.0%, P = 0.820), complete slow pathway block rate (Cryo group 98.5% vs RF group 91.6%, P = 0.088), atrioventricular block rate (Cryo group 0 vs RF group 2.5%, P = 0.413), relapse rate (Cryo group 0 vs RF group 1.7%, P = 0.643). But Cryo group had more advantage than RF group.Efficacy and safety were comparable between cryoablation and radiofrequency ablation for treating patients with AVNRT.

Neutropenia is frequent during treatment of chronic hepatitis C (CHC) with peginterferon and ribavirin. It remains unclear whether neutropenia is associated with infection in CHC. The aim was to study the relationship between neutropenia and infection during treatment with peginterferon and ribavirin for CHC.A retrospective cohort on 399 patients treated with peginterferon α and ribavirin derived from our hospital database was conducted. The occurrence of infections and their relationship to neutropenia were investigated. Potential risk factors for infection were identified by multivariate analysis.During treatment, neutropenia [absolute neutrophil counts (ANC)1.5 × 10⁹/l] occurred in 251 patients, mild neutropenia [ANC (0.75-1.5) × 10⁹/l] occurred in 132 patients, moderate neutropenia [ANC (0.50-0.75) × 10⁹/l] occurred in 103 patients, and severe neutropenia (ANC0.50 × 10⁹/l) occurred in 16 patients. Eighty infections (20.1%) occurred, 14 infections (17.5%) were defined as severe. There was no significant difference in infection rate between patients with and without moderate and severe neutropenia (21.0%, 25/119 vs. 19.6%, 55/280; χ²=0.097, P=0.755). There was no significant difference in infection rate between patients with and without peginterferon dose modifications (21.5%, 31/144 vs. 19.2%, 49/255; χ²=0.307, P=0.580). In multivariate logistic regression analysis, the independent factors associated with infection were age (P=0.021), diabetes (P=0.004), and cirrhosis (P=0.012).Infections during treatment with peginterferon α and ribavirin for CHC are not associated with neutropenia. The independent factors associated with infection are age, diabetes, and cirrhosis.