AIM:To observe the effects of hawthorn leaf polymeric procyanidins ( PPC) on calcium mobiliza-tion of vascular endothelial cells , and to study the underlying mechanism .METHODS: Free calcium in cultured human umbilical vein endothelial cells (HUVECs) was labeled with Fura-2.HUVECs were treated with ATP, a positive control drug, and PPC at concentrations of 12.5, 25 and 50 mg/L..The intracellular calcium concentrations were measured with a living cell microscope for 30 min.RESULTS:PPC concentration-dependently increased the intracellular calcium concen-tration of HUVECs .The intracellular calcium concentrations in 25 and 50 mg/L PPC groups were significantly higher than that in normal group (P<0.01).The dynamic manner of calcium concentration elevations elicited by PPC was a slow in -crease which happened after a latency time of several minutes , lasted for several minutes , and reached a plateau finally . This manner was quite different from that elicited by ATP , a typical SOC operator , hinting different mechanisms between them .Inhibiting the intracellular calcium release did not influence the effects of PPC;however , deleting extracellular calci-um, inhibiting the reverse mode of Na +-Ca2+exchange, or deleting extracellular sodium , restrained or even abolished the effects of PPC.CONCLUSION:PPC elicits calcium mobilization in vascular endothelial cells , which may be one of the mechanisms of the vascular modulatory activity of hawthorn procyanidins .This effect may be achieved through inducing the influx of sodium and then activating the reverse mode of Na +-Ca2+exchange.

Objective To make sciatic nerve traction injury models of rabbit , in order to prospectively evaluate possibility and accuracy of diffusion tensor tracking (DTT) in sciatic nerve injures. Methods The right sciatic nerves of 32 New Zealand white rabbits were selected for traction injury , and the left sciatic nerves were the sham operation side. DTI scan was performed before and after the operation on 1st day , 3rd day, and 1 week, 2, 3, 4, 6 and 8th week respectively, and DTT was reconstructed. Then the length of reconstructed fiber tracts and fiber density index were calculated. After the MRI scan , the sciatic nerve was removed to perform pathologic examination at different time points. Results The difference of the length of reconstructed fiber tracts between nerve traction injury and sham operation side was significant at 1 day~2weeks after operation (P<0.05), while the difference was not significant at 3~8 weeks.The fiber density index of nerve traction injury and sham operation side was significantly different at 1 day~8 weeks(P<0.05). 1day after operation, myelin sheath of traction portion was obviously twisting. 3 days after operation , a large amount of myelin sheath broke down. 2 weeks after operation , axon, myelin sheath degeneration and regeneration coexisted at the same time. 8 weeks after operation , nerve fibers regenerated and restored to normal structure. Conclusion The length time curve and density index-time curve of nerve traction injury are consistent with the changes of pathology , which can be used as a supplementary method to evaluate the degeneration and regeneration in nerve injury.

In the online teaching of Biochemistry course, a variety of network resource platforms (such as Zhihuishu learning network, teleconference, WeChat, QQ, etc) were used to establish a learning community. The teaching content and teaching plan were carefully designed and implemented, enriching the knowledge system of the learning community. And then blending teaching was performed through the combination of live broadcasting and online interaction. In addition to teaching students the basic knowledge of biochemistry, it is also combined with clinical cases and life examples to interact and discuss with students in various forms, giving full play to the advantages of learning community and improving the quality and effect of online learning.

The erythrocyte deformability mainly depends on the composition of the membrane and cytoplasm, which consist of hemoglobin and other constituents. The most of current devices to measure erythrocyte deformability require washing process after the measurement which is labor-intensive and time-consuming. This article introduces an improved measuring system based on microfluidic and machine vision (RSD) which adopts disposable microfluidic channel and conventional laser-diffraction technique to determine erythrocyte deformability. To validate the accuracy and repeatability of RSD, several experiments are conducted to determine deformability of normal erythrocytes measured by RSD and a conventional ektacytometer(LORCA). The measured Elongation Index (EI) by RSD, which is a parameter directly related to erythrocyte deformability, is in excel ent agreement with it measured by LORCA.

ObjectiveTo explore the effect of Jiangtang Xiaozhi tablet （JTXZT） on metabolic dysfunction-associated fatty liver disease and to study the mechanism from the perspective of circadian clock-related genes such as circadian locomotor output cycles kaput （CLOCK）， brain and muscle aryl hydrocarbon receptor nuclear translocator-like protein 1 （BMAL1）， reverse-eritroblastosis receptor （REV-ERB）α and β. MethodA total of 50 male SPF C57BL/6J mice were randomized into normal group （n=10） and modeling group （n=40）. The normal group was fed with normal diet， and the modeling group with high-fat diet for 4 weeks. Then the model mice were randomly classified into model group， high-dose （12.5 g·kg^-1） and low-dose （6.25 g·kg^-1） Jiangtang Xiaozhi tablet groups， and orlistat group （70 mg·kg^-1）， with 10 mice in each group. The normal group and model group received equivalent volume of distilled water （8 weeks）. Then， the body weight of mice was measured， and the content of serum triglyceride （TG）， total cholesterol （TC）， low-density lipoprotein cholesterol （LDL-C）， high-density lipoprotein cholesterol （HDL-C）， aspartate aminotransferase （AST）， and alanine aminotransferase （ALT） was determined with biochemical method. Serum content of free fatty acid （FFA） and leptin was detected by enzyme-linked immunosorbent assay （ELISA）. Pathological changes of liver tissue and epididymal adipose tissue were observed based on hematoxylin-eosin （HE） staining. Liver fibrosis was examined based on Masson's trichrome staining， and changes of lipids based on oil red O staining. The expression of CLOCK， BMAL1， REV-ERBα， and REV-ERBβ was detected by Western blot and immunohistochemistry assay. ResultCompared with the normal group， the model group had high content of TG， TC， LDL-C， HDL-C， AST， ALT， FFA， and leptin （P<0.05， P<0.01）， showed ballooning degeneration and focal microvesicular steatosis of liver cells， enlarged adipocytes， and inflammatory cell clusters and fibrous tissue hyperplasia， and displayed increased protein expression of sterol regulatory element binding protein （SREBP） 1 and peroxisome proliferators-activated receptor （PPAR）γ （P<0.01） and decreased protein expression of PPARα （P<0.05）， CLOCK， BMAL1， REV-ERBα and β （P<0.05， P<0.01）. Compared with the model group， JTXZT-H group down-regulated the content of TG， TC， LDL-C， HDL-C， AST， ALT， FFA， and leptin in mice （P<0.05， P<0.01）， and the JTXZT groups demonstrated reduction in the degree and range of ballooning degeneration of liver tissue， alleviation of the compression of hepatic sinusoidal tissue， unobvious inflammatory cell infiltration and fibrous tissue proliferation， reduction in the expression of SREBP1 and PPARγ （P<0.05， P<0.01）， and rise of the protein expression of PPARα （P<0.01）， CLOCK， BMAL1， REV-ERBα， and REV-ERBβ （P<0.05， P<0.01）. ConclusionJTXZT can significantly alleviate the metabolic dysfunction-associated fatty liver disease in mice caused by high-fat diet. The mechanism is the likelihood that it regulates downstream related lipid metabolism proteins （such as SREBP1， PPARγ， and PPARα）.