ABSTRACT
Objective:To observe any effect of transcranial direct current stimulation (tDCS) on learning, memory ability and the morphology of neurons in the hippocampus and cortex of rats with cognitive impairment, and also to seek any correlation between the rats′ behavior and the thickness of the granular layer in the CA1 region of the hippocampus.Methods:Thirty Sprague-Dawley rats were randomly divided into an observation group, a model group and a control group, each of 10. Cognitive impairment was induced in the observation and model groups by intraperitoneal injection of scopolamine, while the control group was injected with saline solution over the same period of time. After successful modeling, the observation group was given tDCS, while the model and control groups were connected with electrodes but not given any electrical stimulation. After 16 consecutive days of treatment, behavioral changes of each group were quantified using a shuttle box and a Morris water maze. On the 30th day after the mode-ling, the brains were collected to observe any changes in the morphology of the hippocampal and cortical neurons. The thickness of the hippocampal granular layer was also measured.Results:In the observation group the average rate of electrical impulses after the intervention [(60.5±6.67)/min] was significantly less than in the model group [(145.8±19.31)/min], while the time to find a platform was significantly shorter. The rats of the observation group also crossed the D quadrant of the platform significantly more quickly than the model group, on average. Compared with the control group, the granular layer in the CA1 region of the hippocampus [(93.47±1.07)μm] was significantly thinner on average than in the model group but compared with the model group, the observation group had significantly thicker layers [95.17±1.49)μm] on average. The thickness was negatively correlated with the number of shocks and the time to find the platform, but positively correlated with the number of crossings of the platform in the D quadrant.Conclusions:The degree of impairment generated by intraperitoneal injection of scopolamine correlates with the thickness of the CA1 granular layer of the hippocampus, at least in rats. tDCS can improve the learning and memory of such rats. Its mechanism may be related to promoting structural recovery of hippocampal cortical neurons and increasing the thickness of the granular layer.
ABSTRACT
Objective@#To investigate the association between the frequency and filling rate of lateral canals and the sealing quality in the apical third roots of the permanent teeth with failed endodontic treatments, so as to explore the failure factors of root canal therapy.@*Methods@#Clinical records of the permanent teeth with failed endodontic treatments were collected from the Department of Endodontics, Capital Medical University School of Stomatology during a period of 2 years. The teeth were diagnosed as chronic apical periodontitis and then undergone endodontic microsurgery. The sealing quality of the apical root canal was observed by means of periapical radiographs. The surgical treatments were performed and the resected root apices were collected. The samples were scanned by micro-computed tomography and the 3D volume rendered images of the resected root apices were reconstructed. Moreover, the frequency and the filling rate of lateral canals in the apical third roots were calculated. The potential relationship between tooth position and the presence of lateral canals was evaluated.@*Results@#Totally 89 teeth with 89 root apices met the inclusion criteria and were included in the present study. The rate of correct-filling, underfilling and overfilling was 40% (36/89), 32% (28/89), and 28% (25/89), respectively, examined by periapical radiographs. Amongst all of the 89 samples, lateral canals were found in 44 samples. The incidence of apices with lateral canals was 49% (44/89). Furthermore, 3 out of 44 samples were fully filled with material in the lateral canals, and the rest 41 samples showed no filling materials. The filling rate of the lateral canals was 7% (3/44). However, no significant difference was detected between the tooth position and the presence of lateral canals (P>0.05).@*Conclusions@#The sealing quality of the apical third roots in permanent teeth with failed endodontic treatments was not good enough. The incidence of apices with lateral canals was high, but the filling rate of the canals was low. Further studies are needed to explore the relationship between lateral canals and the failure of endodontic treatment.
ABSTRACT
Objective To investigate the accelerating role of recombinant human parathyroid hormone (PTH) in bone fracture repair.Methods 2-month old male Sprague-Dawley rats underwent closed unilateral femoral fracture and intramedullary nail fixation.The rats were divided into 2 equal groups randomly: the treatment group receiving subcutaneous injection of rhPTH(1-34) 10 μg/(kg·d) immediately after operation and for 2,7,14,21 and 42 d,respectively, and the control group receiving subcutaneous injection of normal saline in the same volume.X-ray and micro-CT were conducted at 2, 7, 14, 21 and 42 days after surgery.Results The continuity of porosis between fracture sides was better and fracture line has been blurred in the PTH-treated group at 21 days after fracture compared with the control group, the bone volume (BV),BV/TV, bone mineral density(BMD)and trabecular pattern factor (Tb.Pf) were significantly higher, and trabecular separation (Tb.Sp) and degree of anisotropy (DA) were significantly lower in the PTH-treated group at 42 days after fracture.Conclusions Our findings suggest that a low dose recombinant human parathyroid hormone can accelerate the bone fracture healing, probably through improving the BV, BV/TV, Tb.P and BMD, and decreasing the Tb.Sp and DA.
ABSTRACT
Aim To investigate the role of captopril in insulin resistance of endothelial cells induced by high glucose.Methods 1 .Improvement effect of captopril on insulin resistance in HUVECs was observed.The HUVECs were seeded in a 6-well plate and were ran-domly divided into 5 groups,namely,control group, IR group,IR together with different Cap concentrations (low,medium and high concentration),respectively. 2.Improvement effect of Cap on insulin resistance was mediated by PPARγin HUVECs.HUVECs were ran-domly divided into 6 groups,namely,control group, control +PPARγinhibitor (PI)(1 .0 μmol · L -1 ) group,IR group,IR +PI(1 .0 μmol·L -1 )group,IR +Cap(1 ×1 0 -5 mol·L -1 ) group,and IR +Cap +PI (1 .0 μmol·L -1 )group.All indicators were detected. Results After HUVECs were incubated with media containing 33 mmol·L -1 of glucose for 48 h,the NO levels were significantly decreased while ET-1 levels were significantly elevated,showing a significant differ-ence between IR group and control group (P 0.05).When the HUVECs in IR group were treated with DMEM containing glucose (33 mmol·L -1 )for 48 h and insulin for 30 min,the expression levels of PPARγmRNA and its protein in Cap groups were simi-lar to those in the IR group,and there was no signifi-cant difference between the two groups (P >0.05 );however, the expression levels of phosphorylated PPARγprotein in Cap groups were increased compared with IR group (P <0.05).The levels of NO were sig-nificantly increased whereas the levels of ET-1 were decreased in Cap groups,which had significant differ-ences compared with IR group (P <0.05).Nonethe-less,pre-treating with GW9662,a PPARγinhibitor, the improvement effects of Cap were markedly abol-ished.Conclusions Captopril could improve high glucose-induced insulin resistance of endothelial cells mediated by PPARγ,and the underlying mechanisms are related to the activation of PPARγ,rather than its expression.
ABSTRACT
[ ABSTRACT] AIM:To investigate the protective effect of naringin ( Nar) on the injury of human umbilical vein endothelial cells ( HUVECs) induced by 33 mmol/L high glucose ( HG) and to explore its possible mechanisms.METH-ODS:The injury model was established by treating HUVECs with HG medium for the indicated time (6, 12, 24, 48 and 72 h) , and then the levels of NO, eNOS and p-eNOS were detected, respectively.The effects of Nar on high glucose-in-duced endothelial cell injury were observed.HUVECs were treated with Nar at concentrations of 5, 10, 25, 50 and 100 mg/L for 6 h, 12 h, 24 h, 36 h and 48 h.The levels of NO in the supernatants were measured.The effects of Nar on HG-injured HUVECs were explored by treating the cells with 10 μmol/L of LY294002, a PI3K inhibitor, or 0.5 μmol/L of AKT inhibitorⅣ, an AKT inhibitor, and then the levels of NO, PI3K, AKT, eNOS and their phosphorylated proteins were determined by Western blot.RESULTS:Nar at concentration of 50 mg/L significantly attenuated the injury of endothelial cells induced by high glucose ( P<0.01) , and the protective effects of Nar were abolished by pretreating with the inhibitor of PI3K or AKT (P<0.01).CONCLUSION: Nar protects endothelial cells against the injury induced by high glucose through PI3K/AKT/eNOS pathway.
ABSTRACT
Objective To observe the effect and adverse reactions of iron sucrose injection in treating old patients with iron deficiency anemia(IDA). Methods Thirty-two old patients with IDA were divided into injection group(17 patients)and oral group(15 patients)by random digits table. The effects of improvement on IDA and their adverse reactions were observed. Results After treatment, hemoglobin(Hb)in the injection group and oral group was(100.18±8.71)g/L and(85.80 ± 6.92)g/L(P＜0.01), and serum iron was(23.84±5.34)μmol/L and(14.63±3.29)μmol/L(P＜0.01).There were no obvious adverse reactions in injection group, whereas there were 6 cases(40%)with gastric and colon adverse reaction in oral group. Conclusions The treatment of intravenous injection of iron sucrose can be effectively used to cure old patients with IDA. It has better effect and has lower rate of adverse reaction.