Objective:To investigate the role of reducing resistance and distraction in rapid teeth movement and its reliability by establishing the Beagle dogs’ experimental model.
Methods:The left or right sides in mandibles of 20 beagles were randomly operated with different treatments:distraction twice a day through reducing resistance;distraction 6 times a day through reducing resistance;conventional distraction through reducing resistance;and conventional distraction (the control group). Each treatment was carried out in 10 sides. The pulp vitality, tooth mobility and distance of teeth transportation were evaluated at different time points:before the distraction, distraction after 15 days, retaining 30 days after 15 days of distraction. The degree of inclination, root resorption and alveolar bone density of the compressive areas were evaluated by cone-beam computed tomography images.
Results:The distance of teeth transportation was similar in groups distraction twice daily and 6 times a day through reducing resistance (P>0.05), but their speed of transportation was significantly higher than that of conventional distraction through reducing resistance. The conventional distraction group had the lowest speed of transportation. The pulp vitality of distracted teeth was normal, and no root comprehensive resorption and periodontal defect were found. Distracted teeth in the reduced resistance and distraction groups (13.9°±3.5°) tipped more that in the conventional distraction group (6.6°±1.3°) (P<0.05).
Conclusion:Reducing resistance and distraction are inseparable factors to realize fast teeth moving. The rate of orthodontic tooth movement can be accelerated through resistance reduction and periodontal distraction without obvious unfavorable effects but at minimal acceptable teeth inclination.

Aim To investigate the effects of dopamine(DA)on insulin secretion from rat islets and the possible mechanism.Methods Pancreatic islets were obtained from the pancreatic of male SD rats by collagenase P digestion and histopaque-1077 density gradient separation.Insulin secretion experiment was used to observe the change of insulin release after DA treatments.As to study the potential mechanisms of the effects of DA,patch-clamp experiment and calcuim image technique were applied to test the depolarization-evoked Ca2+ currents,action potential duration and intracellular Ca2+ concentration.Results In 2.8 mmol·L-1 glucose,DA had no effect on insulin secretion;in 16.7 mmol·L-1 glucose,dopamine inhibited insulin secretion in a dose-dependent manner.DA inhibited the inward calcium current,shorten the action potential duration,and reduced the intracellular Ca2+ concentration.Conclusion DA inhibits insulin secretion maybe by decreasing the inward calcium current leading to shorten the action potential duration and reduce the intracellular Ca2+ concentration.

This study aims at trying to establish a novel method of sterility test for injections based on biothermodynamics, in order to overcome the deficiencies of routine sterility tests such as long detecting cycle, low sensitivity and prone to misjudgments. A biothermodynamics method was adopted to rapidly detect the microorganism contamination of injections by monitoring the heat metabolism during the growth of microbe. The growth rate equal to or greater than zero and the heat power difference of P(i) and P(0) with three folds higher than the noise of baseline were chosen as indexes to study the heat change rule of microbe. In this way, the effectiveness of the new method to detect strains required by conventional sterility test or in injection samples was also investigated. Results showed that the Gram-positive bacteria, Gram-negative bacteria and fungi demanded by sterility testing methodology could be detected by biothermodynamics method within 10 hours, with the sensitivity lower than 100 CFU x mL(-1). Meanwhile, this method was successfully applied to the sterility test of Compound Yinchen injection (FFYC), Shuanghuanglian powder injection (SHL) and Compound Triamcinolone injection (TAND) which were sterilized with different degrees. Therefore, the biothermodynamics method, with advantages of fast detection and high sensitivity, could be a complementary solution for conventional sterility tests.

Human maltase-glucoamylase (MGAM) hydrolyzes linear alpha-1,4-linked oligosaccharide substrates, playing a crucial role in the production of glucose in the human lumen and acting as an efficient drug target for type 2 diabetes and obesity. The amino- and carboxyl-terminal portions of MGAM (MGAM-N and MGAM-C) carry out the same catalytic reaction but have different substrate specificities. In this study, we report crystal structures of MGAM-C alone at a resolution of 3.1 Å, and in complex with its inhibitor acarbose at a resolution of 2.9 Å. Structural studies, combined with biochemical analysis, revealed that a segment of 21 amino acids in the active site of MGAM-C forms additional sugar subsites (+ 2 and + 3 subsites), accounting for the preference for longer substrates of MAGM-C compared with that of MGAM-N. Moreover, we discovered that a single mutation of Trp1251 to tyrosine in MGAM-C imparts a novel catalytic ability to digest branched alpha-1,6-linked oligosaccharides. These results provide important information for understanding the substrate specificity of alpha-glucosidases during the process of terminal starch digestion, and for designing more efficient drugs to control type 2 diabetes or obesity.
Acarbose ; chemistry ; Amino Acid Sequence ; Catalytic Domain ; Crystallography, X-Ray ; Glycoside Hydrolase Inhibitors ; Humans ; Hydrogen Bonding ; Intestines ; enzymology ; Kinetics ; Maltose ; chemistry ; Molecular Sequence Data ; Mutagenesis, Site-Directed ; Mutation, Missense ; Oligosaccharides ; chemistry ; Pichia ; Protein Binding ; Recombinant Proteins ; antagonists & inhibitors ; chemistry ; genetics ; Substrate Specificity ; Surface Properties ; alpha-Glucosidases ; chemistry ; genetics

Objective To investigate whether GLT25D2 gene regulates autophagy in acetaminophen (APAP)-induced hepatotoxicity injury.Methods GLT25D2+/+ wild-type C57BL/6J mice and GLT25D2-/- C57BL/6J mice were selected as subjects. ①In vivo experiment: 20 for wild-type mice and 20 for GLT25D2-/- mice were respectively divided into phosphate buffer (PBS) control group and APAP intervention group according to random number table, with 10 mice in each group. The hepatotoxicity injury model of mice was reproduced by intraperitoneal injection of 25 g/L APAP solution 500 mg/kg. The PBS control group was intraperitoneally injected with the same amount of PBS. The mice were sacrificed immediately after model reproduction, and the liver tissues were harvested. Western Blot was used to detect the expressions of autophagy-related proteins ATG5, ATG7, microtubule-associated protein 1 light chain 3 (LC3) and P62. The ultrastructural changes in liver tissue were observed under electron microscope to observe the level of autophagy. ②In vitro experiment: primary hepatocytes extracted by two-step collagen perfusion from one GLT25D2+/+wild-type mouse and one GLT25D2-/- mouse were divided into two parts respectively. One part was treated with 5 mmol/L APAP solution. The cells were harvested at 0, 8, and 12 hours, and the expressions of autophagy-related proteins ATG5, ATG7, LC3, and P62 were determined by Western Blot. The other part was transfected with the green fluorescent protein-LC3 plasmid (GFP-LC3) for 24 hours. The cells were cultured with PBS (PBS control group) or 5 mmol/L APAP (APAP intervention group) for 12 hours, and the positive expression of GFP-LC3 was observed under the fluorescence microscope, thereby reflecting the expression of autophagosomes.Results ①In vivo experiment: compared with the corresponding PBS control group, the expressions of the positive-associated proteins ATG5, ATG7 and LC3-Ⅱ in liver tissue of the APAPintervention group were down-regulated in the wild-type and GLT25D2-/- mice, while the expression of the negative correlation protein P62 was up-regulated, indicating that the overall level of autophagy decreased after treatment with APAP. Compared with wild-type mice, the expressions of autophagy positive correlation proteins ATG5 and ATG7 were up-regulated in GLT25D2-/- mice (ATG5/β-actin: 1.21±0.29 vs. 0.84±0.19, ATG7/β-actin:1.29±0.14 vs. 1.54±0.40, bothP > 0.05), LC3-Ⅱ expression was slightly down-regulated (LC3-Ⅱ/β-actin: 0.52±0.06 vs. 0.58±0.06,P > 0.05), while negative correlation protein P62 was down-regulated (P62/β-actin: 1.13±0.94 vs. 1.54±0.40,P > 0.05), indicating that the expression of autophagy in GLT25D2-/- mice was higher than that in wild-type mice. Ultrastructural observation under electron microscope showed that the number of autophagosomes in the liver tissue of wild-type mice did not change significantly after APAP intervention as compared with that in PBS control group, but the number of autophagosomes in GLT25D2-/- mice was increased. ②In vitro experiment: with the prolongation of APAP intervention, the expressions of ATG5 and ATG7 in the primary hepatocytes of wild-type and GLT25D2-/-mice were up-regulated, LC3 was slightly fluctuated, and the expression of negative-related protein P62 was gradually down-regulated. The peak value or the trough value reached at 12 hours. It was indicated that the expression of autophagy in APAP-stimulated cells was enhanced with a time-dependent manner. Compared with wild-type mice, the expressions of autophagy correlation proteins ATG5, ATG7, LC3-Ⅱ and P62 were up-regulated in GLT25D2-/- mice at 12 hours (ATG5/β-actin: 0.93±0.09 vs. 0.74±0.06, ATG7/β-actin: 0.80±0.09 vs. 0.65±0.10, LC3-Ⅱ/β-actin:1.35±0.30 vs. 1.15±0.20, P62/β-actin: 0.36±0.02 vs. 0.31±0.03, allP > 0.05), indicating that the expression of autophagy was enhanced after gene knockout. Fluorescence microscopy showed that GFP-LC3 positive cells in both wild-type and GLT25D2-/- mice hepatocytes were significantly increased after APAP intervention as compared with those of PBS control group, and the proportion of GFP-LC3 positive cells in GLT25D2-/- mice was significantly higher than that in wild-type mice (0.64±0.08 vs. 0.36±0.05,P < 0.05).Conclusions GLT25D2 is a negative regulator of autophagy. Knockout of GLT25D2 gene can enhance the autophagy level of APAP-induced hepatotoxicity injury in mice.

Objective : To investigate the expression , synergistic relationship and clinical significance of alcohol dehydrogenase (ADH1A) and vascular endothelial growth factor-A (VEGFA) in hepatocellular carcinoma (HCC) . Methods : The expression and correlation of ADH1A and VEGFA in HCC and adjacent normal tissues were ana lyzed by GEPIA . TCGA and GSEA were used to analyze the pathway of ADH1A in HCC . The clinical and patho logical data of 84 patients with HCC were collected , and 54 patients with paracancer normal tissue samples were se lected as controls to analyze the correlation between ADH1A and VEGFA and clinicopathological parameters of HCC . Immunohistochemistry was used to detect the protein expression of ADH1A and VEGFA in cases and con trols , and the correlation between the expression of ADH1A and VEGFA and the clinical progression and prognosis of patients with HCC was analyzed based on clinical pathological parameters and Kaplan Meier. Results : Bioinfor matics analysis found that ADH1A was low expressed in HCC and VEGFA was highly expressed in HCC , and there was a negative correlation between the two ( P < 0.001) ; immunohistochemical detection results showed that the expression of ADH1A in HCC tissue was lower than that in normal tissue adjacent to cancer (P < 0.01) while the expression rate of VEGFA in HCC tissue was significantly higher than that of normal tissue adjacent to cancer (P < 0.01) ; The recurrence rate of vascular thrombus and HCC patients in HCC group with high expression of ADH1A was lower (P < 0.05) . The proportion of tumor diameter > 5 cm , high TNM stage , microsatellite and G2 G3 dif ferentiation in HCC tissues in VEGFA high expression group was higher (P < 0.05) . Kaplan Meier survival analy sis showed that patients with high ADH1A expression and low VEGFA expression had a higher five year survival rate . Conclusion Low expression of ADH1A and high expression of VEGFA in tumor tissues of patients with HCC indicate tumor progression and can be used as one of the prognostic evaluation indicators for patients with HCC .