Microstructural characteristics of Al-20Si-2Cu-0.4Mg-1Ni alloy formed by rheo-squeeze casting after ultrasonic vibration treatment

A swash plate for air conditioning compressor of cars was formed by rheo-squeeze casting with semi-solid Al-Si alloy slurry prepared by ultrasonic vibration process, and the microstructure of this alloy was investigated. Besides the microstructures of primary Si particles and α(Al)+β-Si eutectic phases, non-equilibrium α(Al) particles or dendrites are discovered in the microstructure of the Al-20Si-2Cu-0.4Mg-1Ni alloy. Rapid cooling generated by squeeze casting process rather than the pressure is considered as the main reason for the formation of non-equilibrium α(Al) phase. The sound pressurizing effect of ultrasonic vibration also enables the non-equilibrium α(Al) phases to form above eutectic temperature and grow into non-dendritic spheroids in the process of semi-solid slurry preparation. Non-equilibrium α(Al) phases formed in the hypereutectic Al-Si alloy with ultrasonic vibration treatment, consist of round α(Al) grains formed above the eutectic temperature and a small amount of fine α(Al) dendrites formed under the eutectic temperature. The volume fraction of primary Si particles is decreased significantly by the effect of ultrasonic vibration through increasing the solid solubility of Si atoms in α(Al) matrix and decreasing the forming temperature range of primary Si particles. The average particle diameter and the volume fraction of primary Si particles in microstructure of the swash-plate by rheo-squeeze casting are 24.3 μm and 11.1%, respectively.

喜炎平注射液对巨噬细胞分泌炎性因子的影响

目的:研究喜炎平注射液对LPS诱导的小鼠单核巨噬细释放炎性因子的抑制作用。方法:用LPS刺激体外培养的小鼠单核巨噬细胞RAW264.7释放TNF-α、IL-6、NO等前炎性因子,检测不同浓度的药物对巨噬细胞释放以上炎性细胞因子的抑制作用。通过ELISA的方法检测TNF-α、IL-6的含量,采用Griess法检测培养液上清中NO的含量,以MTT法评价细胞毒性。结果:喜炎平注射液在3～200μg/ml的浓度范围内可明显抑制LPS诱导的巨噬细胞RAW264.7释放炎性因子TNF-α、IL-6及NO,并呈现良好的剂量依赖关系。结论:喜炎平能明显抑制巨噬细胞释放炎性细胞因子TNF-α、IL-6和NO。

Heme oxygenase-1 prevents liver fibrosis in rats by regulating the expression of PPAR_γ and NF-_κB

AIM:To investigate the effects of heme oxygenase(HO)-1 on liver fibrosis and the expression of peroxisome proliferator-activated receptor gamma(PPARγ) and nuclear factor-kappa B(NF-κB) in rats.METHODS:Sixty Wistar rats were used to construct liver fibrosis models and were randomly divided into 5 groups:group A(normal,untreated),group B(model for 4 wk,untreated),group C(model for 6 wk,untreated),group D [model for 6 wk,treated with zinc protoporphyrin Ⅸ(ZnPP-Ⅸ) from week 4 to week 6],group E(model for 6 wk,treated with hemin from week 4 to week 6).Next,liver injury was assessed by measuring serum alanine aminotransferase(ALT),aspartate aminotransferase(AST) and albumin levels.The degree of hepatic fibrosis was evaluated by measuring serum hyaluronate acid(HA),type Ⅳ collagen(Ⅳ-C) and by histological examination.Hydroxyproline(Hyp) content in the liver homogenate was determined.The expres-sion levels of alpha-smooth muscle actin(α-SMA) in liver tissue were measured by real-time quantitative polymerase chain reaction(RT-PCR).The expression levels of PPARγ and NF-κB were determined by RT-PCR and Western blotting.RESULTS:The expression of HO-1 increased with the development of fibrosis.Induction of HO-1 by hemin significantly attenuated the severity of liver injury and the levels of liver fibrosis as compared with inhibition of HO-1 by ZnPP-Ⅸ.The concentrations of serum ALT,AST,HA and Ⅳ-C in group E decreased compared with group C and group D(P < 0.01).Amount of Hyp and α-SMA in the liver tissues in group E decreased compared with group C(0.62 ± 0.14 vs 0.84 ± 0.07,1.42 ± 0.17 vs 1.84 ± 0.17,respectively,P < 0.01) and group D(0.62 ± 0.14 vs 1.11 ± 0.16,1.42 ± 0.17 vs 2.56 ± 0.37,respectively,P < 0.01).The expression of PPARγ at levels of transcription and translation decreased with the development of fibrosis especially in group D;and it increased in group E compared with groups C and D(0.88 ± 0.15 vs 0.56 ± 0.19,0.88 ± 0.15 vs 0.41 ± 0.11,respectively,P < 0.01).The expression of NF-κB increased with the development of fibrosis especially in group D;and it decreased in group E compared with groups C and D(1.43 ± 0.31 vs 1.89 ± 0.29,1.43 ± 0.31 vs 2.53 ± 0.54,respectively,P < 0.01).CONCLUSION:Our data demonstrate a potential mechanism that HO-1 can prevent liver fibrosis by enhancing the expression of PPARγ and decreasing the expression of NF-κB in liver tissues.

A study on the expressions and the correlation of TGF-β1 and α-SMA in healing process of bile duct trauma

Objective: To explore the formation mechanism of benign biliary stricture. Methods: A model of trauma of common bile duct was established in 28 dogs and then repaired. The anasomosis tissues were taken on the 1st week, 3rd week and the 3rd month, 6th month respectively after operation and examined by using light microscopy and elec-tromicroscopy. Macrophage, TGF-p, and a-SMA were studied immunohistochemically. Results: The mucosal epithelium of common bile duct restored poorly, chronic inflammation lasted for a long time, fibroblasts proliferated actively, extracellular matrix overdeposited; and myofibroblasts functioned actively and existed during the whole healing process. Immunohistochemical test showed a high expression of macrophage, TGF-β1 and a-SMA during healing process lasting a long duration. Macrophages were found in the lamina propria under mucosa, TGF-β1 in the granulation tissue, fibroblasts and endothelial cells of blood vesssels, while a-SMA in the myofiroblasts and smooth muscle tissue. Conclusion: The healing of bile duct is in the mode of overhealing. Myofibroblast is the main cause for contracture of scar and stricture of bile duct. The high expression of macrophage, TGF-β1 and a-SMA is closely related to active proliferation of fibroblasts, extracelluar matrix overdeposition and scar contracture of bile duct.

Effects of interferon-alpha on expression of hepatic stellate cell and transforming growth factor-pi and a-smooth muscle actin in rats with hepatic fibrosis

AIM:To investigate the effect of interferon-a (IFN-α) on preventing or reversing hepatic fibrosis in rat experimental model induced by CCI4. METHODS: One hundred and ten Sprague-Dawley rats were divided into five groups: group A (normal controls, n = 18), group B (fibrotic model controls, n = 22), group C (IFN-α prevention, n = 22) initially treated with intramuscular injection of IFN-a in saline daily at the doses of 1× 105 U for 6 wk, group D (IFN-a treatment, n = 24) treated with intra-muscular injection of IFN-a in saline daily at the doses of 1×105 U for 6 wk after the first 6 wk, group E (0.9% sodium chloride treatment control, n = 24) treated with intra-muscular injection of 0.01 mL/kg daily for 6 wk after the first 6 wk. At the end of the experiment, all rats of each group were killed. Samples of the liver obtained by biopsy were subjected to histological, immunohistochemical and electron microscopic studies for the expressions of transforming growth factor-pi (TGF- μ41) and α-smooth muscle actin (α-SMA). RESULTS: The expressions of TGF-pl, the number of activated hepatic stellate cells and a-SMA in hepatic tissue of group C were significantly less than those of group B (P<0.01). The degree of fibrosis score in group B was also significantly less than that of group C under light microscope (P<0.01). CONCLUSION: IFN-a can inhibit the production of TGF-pl, decrease HSC activation and stimulate its apoptosis.

Arsenic trioxide inhibites transgenic tumor necrosis factor-α promoter activity in vascular smooth muscle cells and THP-1 monocytes in vitro

Aim This study was to evaluate the effect of arsenic trioxide （As2O3） on the transgenic TNF-α promoter activity in cultured vascular smooth muscle cells （VSMCs） and THP-1 monocytes. Methods Human TNF-α promoter was constructed by reporter gene system and was transiently transfected into VSMCs and THP-1 in vitro. The promoter activity was tested by luciferase activity with or without LPS and Ang Ⅱ stimulation, before and after different dosage of As2O3 treatment. Results 1. TNF-α promoter effectively expressed in VSMCs and THP-1 compared with CMV promoter （58.3% and 80.9%, respectively）. Both LPS and Ang Ⅱ significantly up-regulated TNF-α promoter activity （P〈0.05）. 2. As2O3 significantly inhibited, both intact and LPS/Ang Ⅱ stimulated promoter activity, in a dose dependent manner （P〈0.05）, and in both cell type. Conclusion These results manifested that, the inhibition effect of As2O3 on the activity of human TNF-α promoter indicated its potential inhibition on pro-inflammatory cytokine genes expression at transcriptional level and its potential anti-inflammatory property in the cardiovascular system.

Theoretical Study on Alpha-Decay Chains of 294 117 117 and 293 176 117

The newly synthesized element 117 and its alpha-decay chains are systematically investigated in the framework of the relativistic mean field theory with parameter sets NL-Z2 and TMA. The ground-state properties of the superheavy nuclei on the alpha-decay chains of 294 117 and 293 117 are calculated. The experimental alpha-decay energies and ha Jr-lives of the two alpha-decay chains are reasonably reproduced by the model The detailed discussions on the binding energies, alpha-decay energies, half-lives, quadrupole deformations, potential energy curves, and single particle levels of the two alpha-decay chains are made.

A Modification of α in SRK Equation of State and Vapor-Liquid Equilibria Prediction

Based on results of saturated vapor pressures of pure substances calculated by SRK equation of state, the factor a in attractive pressure term was modified. Vapor-liquid equilibria of mixtures were calculated by original and modified SRK equation of state combined with MHV1 mixing rule and UNIFAC model, respectively. For 1447 saturated pressure points of 37 substance including alkanes; organics containing chlorine, fluorine, and oxygen; inorganic gases and water, the original SRK equation of state predicted pressure with an average deviation of 2.521% and modified one 1.673%. Binary vapor-liquid equilibria of alcohols containing mixtures and water containing mixtures also indicated that the SRK equation of state with the modified a had a better precision than that with the original one.

Homological properties of modules characterized by matrices

Some homological properties of R-modules were investigated by matrices over aring R. Given two cardinal numbers α, β and an α x β row-finite matrix A, it was proved thatExt_R^1(R^((α))/R^((β))A, M) = 0 if and only if M_α/r_(M_α)(R^((β))A) ≈ Hom_R(R^((β))A,M) ifand only if r_(M_β)l_(R^((β)))(A) = AM_α. Thus, the notion of (m,n)-injectivity was extended.Moreover, ( α, β) -flatness was characterized via annihilators of matrices, factorizations ofhomomorphisms as well as homological groups so that (m, n)-flat modules, f-projective modules andn-projective modules were consolidated under the notion of (α, β)-flat modules. Furthermore, acharacterization of left R-ML modules and some equivalent conditions for R^((β)) to be left R-MLwere presented. Consequently, the notions of coherent rings, (m, n)-coherent rings and π-coherentrings were consolidated under that of (α, β)-coherent rings.

Projectively flat arctangent Finsler metric

In this work, we study a class of special Finsler metrics F called arctangent Finsler metric, which is a special （α, β）-metric, where a is a Riemannian metric and β is a 1-form, We obtain a sufficient and necessary condition that F is locally projectively fiat if and only if α and β satisfy two special equations. Furthermore we give the non-trivial solutions for F to be locally projectively fiat. Moreover, we prove that such projectively fiat Finsler metrics with constant flag curvature must be locally Minkowskian.

Gastrointestinal stromal tumor of duodenum:a cause of upper gastrointestinal hemorrhage

Objective:The aim of the study was to report an anemia patient with melena for five years caused by duodenal gastrointestinal stromal tumor (GIST), who required surgical treatment. Methods: A 44-year old man present with anemia appearance was admitted to our center (Department of Hepatobiliary Surgery, Union Hospital, Huazhong University of Science and Technology, China) due to sustaining melena for five years. Endoscopy found no special mucosal abnormalities in the duodenal lumen. Computed Tomography showed a well-demarcated mass, 7.4 cm in diameter, located between the C loop of duodenum and pancreatic head. Pylorus-preserving pancreaticoduodenectomy and right hemicolectomy were performed when the patient's general conditions were improved. He recuperated successfully and was discharged on the 21st postoperative day. No complications happened during the period of hospital stay. Results: Histological and immunohistochemical study revealed a high risk invasive duodenal GIST which was positive for CD117, CD34, α-smooth muscle actin and negative for S-100. Conclusion: Duodenal GIST can be a source of upper gastrointestinal hemorrhage; surgical treatment is still a reasonable choice for the patients with invasive duodenal GIST.

Ac-SDKP对ROCK通路介导矽肺大鼠肌成纤维细胞分化抑制作用

目的探讨N-乙酰基-丝氨酰-天门冬酰-赖氨酰-脯氨酸(Ac-SDKP)对Rho相关卷曲螺旋形成蛋白激酶(ROCK)通路介导的肌成纤维细胞分化的抑制作用。方法无特定病原体级建康成年雄性Wistar大鼠120只随机分为对照组(支气管灌注1 ml灭菌生理氯化钠溶液)、矽肺模型组[支气管灌注质量浓度为50 g/L二氧化硅(SiO2)1 ml]、Ac-SDKP前处理组(支气管灌注质量浓度为50 g/L SiO21 ml,灌注前给予Ac-SDKP),分别于染尘后1、2、4、8周处死(每亚组10只)。采用免疫组织化学法检测肺组织内α-平滑肌肌动蛋白(α-SMA)的分布与表达,免疫印迹法检测肺组织内转化生长因子-β1(TGF-β1)、ROCK、血清反应因子(SRF)、α-SMA以及Ⅰ型和Ⅲ型胶原蛋白的表达。结果与对照组比较,矽肺模型组大鼠肺组织内TGF-β1、ROCK、SRF、α-SMA以及Ⅰ型和Ⅲ型胶原蛋白表达均增加(P<0.05),并具有一定时间依赖性。与矽肺模型组比较,Ac-SDKP前处理4、8周组,大鼠肺组织内TGF-β1、ROCK、SRF、α-SMA以及Ⅰ型和Ⅲ型胶原蛋白表达均降低(P<0.05)。结论 Ac-SDKP能够通过对TGF-β1介导的ROCK信号转导通路的调控,阻抑矽肺大鼠肌成纤维细胞的分化。

Projectively flat exponential Finsler metric

In this paper, we study a class of Finsler metric in the form F=αexp(β/α)+εβ, where α is a Riemannian metric and β is a 1-form, ε is a constant. We call F exponential Finsler metric. We proved that exponential Finsler metric F is locally projectively flat if and only if α is projectively flat and β is parallel with respect to α. Moreover, we proved that the Douglas tensor of expo-nential Finsler metric F vanishes if and only if β is parallel with respect to α. And from this fact, we get that if exponential Finsler metric F is the Douglas metric, then F is not only a Berwald metric, but also a Landsberg metric.

Effect of Zhuyeshigao granule on tumor necrosis factor-α and inter leukins serum protein levels in rats with radiation esophagitis

OBJECTIVE： To investigate the effects of Zhuyesh- igao granule （ZSG） on tumor necrosis factor-a （TNF-a）, interleukin-1 （IL-1）, IL-2, IL-6, and IL-8 in rats with radiation esophagitis. METHODS： Fifty Wistar rats were randomly divid- ed into five groups （10 rats in each group）： con- trol （without radiation）, saline-treated, and low, medium, and high-dose ISG-treated groups. Rats were given normal saline （10 mL/kg） or 1.15, 2.3, or 4.6 g/kg ZSG by intragastric administration once a day for 7 days. A rat model of radiation esophagi- tis was established by local irradiation of Co60 （490.25 cGy/min, totaling 30 Gy）. The administra- tion of ZSG was continued for another 7 days and on the 7th day post-irradiation, inferior vena cavablood was collected. The serum was separated, and TNF-a, IL-1, IL-2, 11_-6, and IL-8 protein levels were determined. RESULTS： Inflammatory response factors were found in the serum of each group. However, levels in ZSG-treated groups were significantly lower than in the saline-treated group （P〈0.05）. CONCLUSION： ZSG may prevent the development of radiation esophagitis, perhaps by inhibiting the generation and release of the inflammatory re- sponse factors TNF-a, IL-1, IL-2, IL-6, and IL-8.

Inhibition mechanism of compound ethanol extracts from Wuweizi(Fructus Schisandrae Chinensis) on renal interstitial fibrosis in diabetic nephropathy model mice

OBJECTIVE：To evaluate inhibition effect and mech- anism of compound ethanol extracts from Wuweizi （Fructus Schisandrae Chinensis）, Chuanxiong （Rhi- zoma Chuanxiong） and Muli （Cocha Ostreae） （FRC） on glomerular and tubular interstitial fibrosis in streptozocin （STZ）-induced diabetic nephropathy （ND） model mice. METHODS： Twenty-seven male C57BL/6 mice were divided randomly into 3 groups： nondibetic （ND）, STZ-induced diabetic （D）, and STZ-induced diabetic that were treated with .5 g. kg1. daylof FRC by oral gavage （DFRc）, with 9 in each group. The protein ex- pressions of E-cadherin, a-smooth muscle actin （a-SMA）, Plasminogen Activator Inhibitor-1 （PAl-l） in renal tissues were investigated by Western blot- ting. The expressions of fibronectin （FN） and o-SMA were detected by immunohistochemical method. The morphological changes of renal tissues were observed under a microscope. RESULTS： Renal tissues in the DFRC group showed a lessened degree of fibrosis. Meanwhile, the expres- sions of FN, o-SMA and PAl-lwere significantly lower in the DrRc group than those in the D group （all P〈0.05）.CONCLUSION： FRC can ameliorate the DN in the C57BL/6 mice, and its mechanism may relate to in- hibition on the epithelial to mesenchymal transdif- ferentiation, endothelial-myofibroblast transition and PAl-1 expression.