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Cholesterol gallstone (CG) is a common, frequent biliary system disease in China, with a complex and multifactorial etiology. Declined gallbladder motility reportedly contributes to CG pathogenesis. Furthermore, interstitial Cajal-like cells (ICLCs) are reportedly present in human and guinea pig gallbladder tissue. ICLCs potentially contribute to the regulation of gallbladder motility, and aberrant conditions involving the loss of ICLCs and/or a reduction in its pacing potential and reactivity to cholecystokinin may promote CG pathogenesis. This review discusses the association between ICLCs and CG pathogenesis and provides a basis for further studies on the functions of ICLCs and the etiologies of CG.

BACKGROUND Loss and/or dysfunction of interstitial Cajal-like cells (ICLCs) in the gallbladder may promote cholesterol gallstone formation by decreasing gallbladder motility. AIM To study the effect of cholesterol on the proliferation and apoptosis of ICLCs from guinea pig gallbladders. METHODS Guinea pig gallbladder ICLCs were isolated and cultured in vitro. The cells were exposed to cholesterol solutions at different concentrations (0, 25, 50, and 100 mg/L) for 24 h. Then, cell proliferation was detected by the CCK-8 method and the apoptosis rate was detected by flow cytometry. Further, the expression of the c-Kit protein was detected by Western blot and the expression level of c-Kit mRNA in the cells was detected by real-time quantitative PCR. RESULTS After ICLCs were cultured with cholesterol at concentrations of 25, 50, and 100 mg/L, the proliferation rates decreased significantly (P < 0.05), whereas the apoptosis rates increased significantly (P < 0.05). Moreover, the expression of c-Kit protein and mRNA decreased significantly (P < 0.05). CONCLUSION High cholesterol concentrations can inhibit the proliferation of ICLCs and promote apoptosis. This decrease in the ICLC proliferation rate might be caused by the inhibition of the stem cell factor/c-Kit signaling pathway.

Background Xin-Ji-Er-Kang (XJEK) as a herbal formula of traditional Chinese medicine (TCM) has shown the protective effects on myocardial function as well as renal function in mouse models of myocardial infarction. Hypothesis/Purpose We investigated the effects of XJEK on cardiovascular- and renal-function in a heart failure mouse model induced by high salt (HS) and the associated mechanisms. Study design For the purpose of assessing the effects of XJEK on a hypertensive heart failure model, mice were fed with 8% high salt diet. XJEK was administered by oral gavage for 8 weeks. Cardiovascular function parameters, renal function associated biomarkers and XJEK's impact on renin-angiotensin–aldosterone system (RAAS) activation were assessed. To determine the underlying mechanism, the calpain1/junctophilin-2 (JP2)/sarcoplasmic reticulum Ca2+ ATPase (SERCA2a) pathway was further studied in AC16 cells after angiotensin II-challenge or after calpastatin small interfering RNA (siRNA) transfection. Results Mice on HS-diet exhibited hypertensive heart failure along with progressive kidney injury. Similar to fosinopril, XJEK ameliorated hypertension, cardiovascular-and renal- dysfunction in mice of HS-diet group. XJEK inhibited HS-induced activation of RAAS and reversed the abnormal expression pattern of calpain1and JP2 protein in heart tissues. XJEK significantly improved cell viability of angiotensin II-challenged AC16 cells. Moreover, XJEK's impact on calpain1/JP2 pathway was partly diminished in AC16 cells transfected with calpastatin siRNA. Conclusion XJEK was found to exert cardiovascular- and renal protection in HS-diet induced heart failure mouse model. XJEK inhibited HS-diet induced RAAS activation by inhibiting the activity and expression of calpain1 and protected the junctional membrane complex (JMC) in cardiomyocytes.

To investigate the effect of interstitial Cajal-like cells (ICLCs) on contraction of gallbladder muscle strips; and to analyze the changes of ICLCs during cholesterol gallstone formation in guinea pig.The cholesterol gallstone animal model was made by feeding guinea pig with high cholesterol diet (HCD). In vitro isolated gallbladder muscle strips were prepared. Gallbladder motility was assessed by the contraction frequency and amplitude of slow wave in response to CCK-8. The alteration in ICLC density was estimated by using immunohistochemistry. The expression of c-kit and stem cell factor (SCF) were determined.The amplitude and frequency of slow wave was significantly lower in gallbladder muscle strips with the impaired ICLCs. And it is correlated with the decreased contractile response to CCK-8. In HCD guinea pig, the ICLC density and bile flow in response to CCK-8 were remarkably decreased. The results indicated that gallbladder ICLCs can create slow wave potential, and also get involved in the regulation of CCK-8 induced gallbladder smooth muscle motility. In the process of cholesterol gallstone formation, ICLC density clearly decreased. This further impaired gallbladder motility. The decrease in ICLC density may result from decreased expression of c-kit and SCF during cholesterol gallstone formation.

In this paper, one Automatic Tensioning Device which can realize multi-time tensioning is designed. Through structural designing and motion designing to get the main structure, through initially calculating to get its each part parameters, through ANSYS optimization designing to get its minimum size parameters of each device under the strength conditions, to achieve its goal to optimize the quality of the lightest. Main components of Automatic Tensioning Device are selected as the research object, establishing the optimal equation, using the optimization module of Goal Driven Optimization of ANSYS to optimize its size. The results show that with the strength requirement contented, Automatic Tensioning Device can be optimized by optimizing the Wall Panel.

To observe the reversion of multi-drug resistance by proteasome inhibitor bortezomib in K562/DNR cell line and to analyze the possible mechanism of reversion of multidrug-resistance.MTT method was used to determine the drug resistance of K562/DNR cells and the cellular toxicity of bortezomib. K562/DNR cells were cultured for 12 hours, 24 hours and 36 hours with 100 μg/ml DNR only or plus 4 μg/L bortezomib. The expressions of NF-κB, IκB and P-gp of K562/DNR were detected with Western blot method, the activity of NF-κB was tested by ELISA method and the apoptosis rate was observed in each group respectively.The IC50 of DNR on cells of K562/S and K562/DNR groups were 1.16 μg/ml and 50.43 μg/mL, respectively. The drug-resistant fold was 43.47. The IC10 of PS-341 on Cell strain K562/DNR was 4 μg/L. Therefore, 4 μg/L was selected as the concentration for PS-341 to reverse drug-resistance in this study. DNR induced down-regulation of IκB expression, up-regulation of NF-κB and P-gp expression. After treatment with PS-341, a proteasome inhibitor, the IκB degradation was inhibited, IκB expression increased, NF-κB and P-gp expression decreased in a time dependent manner. Compared to DNR group, the NF-κB p65 activity of DNR+PS-341 group was decreased. Compared to corresponding DNR group, DNR induced apoptosis rate increases after addition of PS-341 in a time dependent manner.Proteasome inhibitor bortezomib can convert the leukemia cell drug resistance. The mechanism may be that bortezomib decreases the degradation of IκB and the expression of NF-κB and P-gp, therefore induces the apoptosis of multi-drug resistant cells.

Background: NF-κb is a transcription factor in eukaryotic cells that binds to inhibitor protein κB (IκB) in the cytoplasm. Once stress responses occur, IκB is phosphorylated and degraded by the proteasome. Upon dissociation with IκB, activated NF-κB enters the nucleolus and induces the expression of mdr1. MDR-1 encodes the P-glycoprotein (P-gp), which is an ATP-dependent drug efflux pump which lowers intracellular drug concentration resulting in drug resistance. Bortezomib (VELCADE®) is an anti-cancer drug that is a first-in-class proteasome inhibitor and is indicated in treatment of multiple myeloma (MM) patients. However, its role in myeloid leukemia therapy, is still being evaluated. In this study, we observed the effect of bortezomib on the expression of NF-κB AIκB and P-gp in daunorubicin (DNR) resistant cell line K562/DNR, a myeloid cell line; we also discussed the molecular mechanism and functional characteristics of reversing resistance by bortezomib and provided experimental basis to overcome multi-drug resistance in myeloid leukemia. Methods: Resistance of cell line will be evaluated by MTT; After treating K562/DNR for 36h with DNR (100‚•g/ml) alone or combined with bortezomib at different concentration (0.4 mg/L A4 mg/L or 40 mg/L), the expression levels of NF-κB AIκB and P-gp, the activity of NF-κB p65 and the apoptosis rates of cells will be measured by Western blot followed by ELISA and flow cytometry, respectively. After treating K562/DNR for 12h, 24h and 36h with DNR (100 mg/ml) alone or combined with bortezomib (4 mg/L), the same indexes will also be measured; Statistical analysis: With SPSS software, the two group means were compared by t-test and the two sample rates were compared by χ2-test. Results: After treating K562/DNR for 36h with DNR alone or combined with bortezomib at different concentrations, apoptosis rates were measured by flow cytometry. As a single agent, botezomib at concenration of 0.4 mg/L and 4 mg/L did not result in an increase in the rate of apoptosis. However, an increase in apoptosis rate was observed with bortezomib 40 mg/L. In contrast, a combination of DNR and bortezomib resulted in significant increases in apoptosis rate at all doses of bortezomib. Moreover, a dose response was observed. After treating K562/DNR for 12h A24h and 36h with DNR alone or combined with bortezomib, we utilized Western blot to assess the intracellular level of NF-κB AP-gp and IκB. Compared with negative control, DNR as a single agent increased the level of NF-κB AP-gp and decreased the level of IκB. After the addition of bortezomib, the level of NF-κB AP-gp decreased while IκB level increased; furthermore, the effect increased by prolonging the treating time. Conclusion: Based on our observations bortezomib may reverse drug resistance of K562/DNR cell line to DNR. Under optimized conditions, the effect of reversing resistance follows a dose-dependent manner and a time-dependent manner and increases with increasing the concentrations of bortezomib and duration of cellular exposure.