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101.
Delay of axon regeneration after peripheral nerve injury usually leads to progressive muscle atrophy and poor functional recovery. The Wnt/β-catenin signaling pathway is considered to be one of the main molecular mechanisms that lead to skeletal muscle atrophy in the elderly. We hold the hypothesis that the innervation of target muscle can be promoted by accelerating axon regeneration and decelerating muscle cell degeneration so as to improve functional recovery of skeletal muscle following peripheral nerve injury. This process may be associated with the Wnt/β-catenin signaling pathway. Our study designed in vitro cell models to simulate myelin regeneration and muscle atrophy. We investigated the effects of SB216763, a glycogen synthase kinase 3 beta inhibitor, on the two major murine cell lines RSC96 and C2C12 derived from Schwann cells and muscle satellite cells. The results showed that SB216763 stimulated the Schwann cell migration and myotube contraction. Quantitative polymerase chain reaction results demonstrated that myelin related genes, myelin associated glycoprotein and cyclin-D1, muscle related gene myogenin and endplate-associated gene nicotinic acetylcholine receptors levels were stimulated by SB216763. Immunocytochemical staining revealed that the expressions of β-catenin in the RSC96 and C2C12 cytosolic and nuclear compartments were increased in the SB216763-treated cells. These findings confirm that the glycogen synthase kinase 3 beta inhibitor, SB216763, promoted the myelination and myotube differentiation through the Wnt/β-catenin signaling pathway and contributed to nerve remyelination and reduced denervated muscle atrophy after peripheral nerve injury.  相似文献   
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The purpose of this study attempted to analyze the potential risk factors for internal carotid artery injury during simple nasopharyngeal surgeries with or without an endoscopic aid. One hundred and seventy magnetic resonance imaging scans (340 halves) of the brain were retrospectively reviewed and studied. Anatomic variations of carotid arteries were classified, and various distances from the internal carotid arteries to the nasopharyngeal subsites were directly measured on the scans. The mean distances between the internal carotid arteries and nasopharyngeal subsites were significantly shortened in patients with nasopharyngeal internal carotid artery aberrancy, female gender, and lower body weight. The distance to the posterior nasopharyngeal wall was also shortened with age. However, the severity of nasopharyngeal carotid artery variations (kinking and coiling) did not reflect the shortening of mean distances to nasopharyngeal subsites. In conclusion, from multiple linear regression analysis, we found that the risk of an internal carotid artery injury during simple nasopharyngeal surgeries with or without an endoscopic aid is greatest in adult patients with nasopharyngeal carotid artery aberrancy, followed by female gender, lower body weight, and increasing age.  相似文献   
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目的观察日达仙稀释液对化疗后口腔溃疡患者的治疗作用。方法选择住院化疗后并发口腔溃疡患者68名,随机分为治疗组及对照组,治疗组用日达仙液涂抹溃疡面,对照组用锡类散涂抹溃疡面,观察两组间口腔溃疡疗效的差异。结果治疗组患者平均溃疡治愈时间(4.87±0.96)d及平均疼痛指数(3.84±1.21)分均明显低于对照组,差异均有统计学意义(t分别=7.55、5.46,P均<0.05)。结论日达仙稀释液对患者化疗后并发的口腔溃疡有较好疗效。  相似文献   
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The acinus-mimicking microfluidic chip, which simulates the in vivo condition of the liver, was developed and reported in this paper. The gradient microenvironment of the liver acinus is replicated within this proposed microfluidic chip. The advantage of this acinus-mimicking chip is capable of adjusting the concentration gradient in a relatively short period of time at around 10 s. At the same instance the non-linear concentration gradient can be presented in the various zones within this microfluidic chip. The other advantage of this proposed design is in the convenience of allowing the direct injection of the cells into the chip. The environment within the chip is multi-welled and gel-free with high cell density. The multi-row pillar microstructure located at the entrance of the top and bottom flow channels is designed to be able to balance the pressure of the perfusion medium. Through this mechanism the shear stress experienced by the cultured cells can be minimized to reduce the potential damage flow from the perfusion process. (3)The fluorescence staining and the observations of the cell morphology verify the life and death of the cells. The shear stress experienced by the cells in the various zones within the chip can be effectively mapped. The serum glutamic oxaloacetic transaminase (SGOT) collected from the supernatants was used to determine the effects of the degassing process and the shear stress of the medium flow on the cultured cells.  相似文献   
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ObjectiveThis study explores the correlation between plasma lipoprotein-associated phospholipase A2 (Lp-PLA2) and coronary heart disease (CHD) by comparing the level of plasma Lp-PLA2 in the plasma of patients with different types of CHD.MethodsBlood samples were collected from 56 patients diagnosed with CHD by the Department of Cardiology of the First People''s Hospital of Foshan and 34 healthy subjects from February 2013 to January 2014. We measured the concentration of plasma Lp-PLA2 and determined the levels of total cholesterol (Tch), triglyceride (TG), apolipoprotein A1 (Apo-A1), apolipoprotein B (Apo-B), high density lipoprotein-cholesterol (HDL-c), low density lipoprotein-cholesterol (LDL-c), lipoprotein a (Lp(a)), glucose (Glu), and high-sensitivity C-reactive protein (hs-CRP). The concentration of plasma Lp-PLA2 in the healthy control group and each subgroup of CHD patients were compared and analyzed for correlations of plasma Lp-PLA2 between the patients in different CHD subgroups and several laboratory indicators.ResultsThe concentration of plasma Lp-PLA2 in each subgroup of CHD was significantly higher than in the control group (P < 0.05). The concentration of Lp-PLA2 in the unstable angina pectoris (UAP) group and acute myocardial infarction (AMI) group were significantly higher than in the stable angina pectoris (SAP) group (P < 0.05), and the concentration of plasma Lp-PLA2 in the AMI group was significantly higher than in the UAP group (P < 0.05). The concentration of plasma Lp-PLA2 in the CHD group merely showed a positive correlation (r = 0.493, P < 0.05) with the hs-CRP group, but the levels of Tch, TG, Apo-A1, Apo-B, HDL-c, LDL-c, Lp(a) and Glu did not.ConclusionsThe concentration of plasma Lp-PLA2 in patients with CHD was higher than that in the control group. The concentration of plasma Lp-PLA2 in the subgroups of CHD patients varied greatly from each other. The inflammatory response of atherosclerosis might be resulted from the synergy of plasma Lp-PLA2 and hs-CRP.  相似文献   
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This study sought to prepare a self-microemulsion drug delivery system containing zingerone (Z-SMEDDS) to improve the low oral bioavailability of zingerone and anti-tumor effect. Z-SMEDDS was characterized by particle size, zeta potential and encapsulation efficiency, while its pharmacokinetics and anti-tumor effects were also evaluated. Z-SMEDDS had stable physicochemical properties, including average particle size of 17.29 ± 0.07 nm, the zeta potential of -22.81 ± 0.29 mV, and the encapsulation efficiency of 97.96% ± 0.02%. In vitro release studies have shown the release of zingerone released by Z-SMEDDS was significantly higher than free zingerone in different release media. The relative oral bioavailability of Z-SMEDDS was 7.63 times compared with free drug. Meanwhile, the half inhibitory concentration (IC50)of Z-SMEDDS and free zingerone was 8.45 μg/mL and 13.30 μg/mL, respectively on HepG2. This study may provide a preliminary basis for further clinical research and application of Z-SMEDDS.  相似文献   
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