Objective:To analyze the prognosis of replanted permanent teeth in children and associated factors. To determine the onset time of root resorption and related factors. Methods: Clinical data of replanted teeth treated in Department of Pediatric Dentistry, Peking University, School and Hospital of Stomatology, from January 2000 to December 2006,were collected, and the follow-up period was no less than six months. The Fisher's exact test and cox regression were used for statistical analysis. Results: The study comprised of 39 patients with 50 replanted permanent teeth. The periodontium healing rate was 18%, while root resorption rate was 82%. Replacement resorption was the most common type of root resorption (64%).The factors significantly affecting periodontium healing were stage of root development and storage of avulsed teeth.Stage of root development and the time of endodontic treatment significantly affected the onset time of root resorption(P<0.05). Conclusion: Replacement resorption is the most common type of root resorption. The factors significantly affecting periodontium healing are stage of root development and storage of avulsed teeth. Stage of root development and the time of endodontic treatment significantly affect the onset time of root resorption.

This research is to investigate and analyze the reading characteristics of students in medical college of Foshan Science and Tecnoology University during their clinical practice period,to understand the trainee's reading motive,their expectation of a reading teacher,and their demanding of serve from the college library,thus exploring the method and the countermeasures of the reading guides

The preparation method, serum stability, efficiency of cellular uptake and apoptosis induction of the cell penetrating peptide TAT and cleavable PEG co-modified liposomes loaded with paclitaxel (C-TAT-Lipo) were investigated. The best preparation procedure was performed by orthogonal test based on single factor screening method. First, the paclitaxel (PTX)-loaded liposomes were prepared by filming-rehydration method, evaluated with entrapment efficiency and polydispersity index. The morphology of C-TAT-Lipo was characterized by transmission electron microscopy. Turbidity variations were monitored in the presence of fetal bovine serum (FBS) to evaluate the serum stability of the liposomes developed here. Next, the efficiency of cellular uptake of different Rho-PE-labeled liposomes on B16F1 cells in vitro was evaluated by confocal laser scanning microscopy (CLSM) and flow cytometry. The quantitative analysis of apoptosis induced by different PTX-loaded liposomes was performed by Annexin V-FITC/PI double staining. The optimal formulation was as follows: Chol : lipid: 1 : 8 (molar ratio); drug : lipid: 1 : 40 (mass ratio); lipid concentration: 3 mmol x L(-1); temperature of hydration: 25 degrees C. The mean size and polydispersity index of C-TAT-Lipo were about (97.97 +/- 3.68) nm and 0.196 +/- 0.037, the zeta potential was (-0.89 +/- 0.45) mV, the entrapment efficiency of paclitaxel was (90.16 +/- 1.53)%. The particle sizes did not exhibit significant variations in 50% FBS over 24 h at 37 degrees C. The efficiency of cellular uptake of the C-TAT-Lipo increased 1.40 fold following the cleavage of PEG. Apoptosis analysis showed 59.3% increase of the apoptosis and necrosis profile of C-TAT-Lipo after the detachment of PEG shells, which was markedly higher than that of N-TAT-LP with or without glutathione and SL, respectively. The results indicate that the C-TAT-Lipo is successfully prepared by filming-rehydration method and shows significant antitumor activities.
Animals ; Annexin A5 ; Apoptosis ; Cell Line, Tumor ; Cell-Penetrating Peptides ; pharmacology ; Fluorescein-5-isothiocyanate ; analogs & derivatives ; Liposomes ; chemistry ; Melanoma, Experimental ; Mice ; Microscopy, Confocal ; Paclitaxel ; pharmacology ; Particle Size ; Polyethylene Glycols ; chemistry

0.05).Conclusions:There was no difference in terms of both effect and toxicity among the three regimens. All of them were effective and could be well tolerated by advanced colorectal cancer patients.

Objective To detect the effect of deep hypothermia on the function of mitochondria in hippocampus after global ischemia in rats and to explore the protection mechanism. Methods The animal model of cardiopulmonary bypass (CPB) was established in rats that were then randomly divided into three groups,ie,control group,normothermia ischemia group and hypothermia ischemia group,eight rats per group.The mitochondria was extracted from the hippocampus of each rats for observing the mitochondrial respiratory function,the activities of succinate dehydrogenase (SDH),the cytochrome oxidese(CCO),the lnembrane fluidity and the content of intramitochondria free calcium and MDA. Resuits The content of intramitochondria free calcium and MDA in the normothermia ischemia group was increased significantly compared to the control group and that in the hypothermia ischemia group wag decreased significantly compared with the normothermia ischemia group(P<0.05).Respiratory state Ⅲ (R3),respiratory state IV(R4),P/O ratio and oxidative phosphorylation (OPR) in the normothermia ischemia group were decreased significantly compared to the control group (P<0.05).R3,R4,P/O ratio and OPR in the hypothermia ischemia group were increased significantly compared with the normothermia ischemia group (P<0.05).Membrane fluidity in the normothermia ischemia group wag decreased significantly compared to the control group (P<0.01),while that in the hypothermia ischemia group was increased significantly compared with the normothermia ischemia group(P<0.05).The activities of SDH and CCO in the normothermia ischemia group were decreased significantly compared to the control group (P<0.01),while those in the hypothermia ischemia group were increased significantly compared with the normothermia ischemia group (P<0.05). Conclusion Profound hypothermia exerts a protective effect on the function of mitochondria in the hippocampus after global ischemia in rats.

OBJECTIVETo explore the molecule mechanism of Salidroside inducing directional differentiation of mouse mesenchymal stem cells (MSCs) into neuronal cells.

METHODSThe mouse multipotent mesenchymal precursor cell line (D1) was taken as the objective. Cultured MSCs were divided into the negative control group (complete culture solution), the positive control group (containing 1 mmol/L β-mercaptoethanol), the Salidroside induced group (20 mg/L Salidroside), and the blocked group (20 ng/ ml DKK1, a special inhibitor of Wnt/β-catenin signal pathway). All cells were inoculated in a 6-well plate (1 x 10(4) cells/cm2) and grouped for 24 h. The expression of p-catenin was detected by fluorescence Immunochemistry in the negative control group, the positive control group, and the Salidroside induced group. The expression of neuron-specific enolase (NSE), beta 3 class III tubulin (β-tubulin III), nuclear receptor related factor 1 (Nurr1), glial fibrillary acidic protein (GFAP) mRNA, Wnt3a, β-catenin, low-density lipoprotein receptor-related protein6 (LRP6), Axin mRNA were detected using reverse transcrip- tion PCR (RT-PCR). The expression of β-catenin and NSE protein were analyzed by Western blot in the negative control group, the positive control group, and the Salidroside induced group. Ca2+ chelating agents (EGTA), L-type Ca2+ channel blocker (Nifedpine), and IP3Ks special inhibitor (LY294002) were used to block Ca2+ signal pathway respectively. The expression of Wnt3a, LRP-6, Axin, glycogen syn- thase kinase (GSK-3), and β-catenin mRNA were detected by RT-PCR. The β-catenin protein expression was analyzed using Western blot.

RESULTSCompared with the positive control group, β-catenin protein was strong positively expressed; the expression of Wnt3a, β-catenin, LRP6, Axin, NSE, β-tubulin III, Nurr1 mRNA, and NSE protein were obviously up-regulated in the Salidroside induced group (P < 0.01). Compared with the positive control group and the Salidroside induced group, β-catenin, NSE, Nurr1, and β-tubulin III mRNA expression decreased; β-catenin and NSE protein expression were also down-regulated in the blocked group (P < 0.01). Compared with the Salidroside induced group, the expression of Wnt3a, LRP-6, β-catenin, and Axin mRNA were down-regulated in the Ca2+ signal blocked group and the salidroside induced group (P < 0.01, P < 0.05).

CONCLUSIONSalidroside affected directional differentia- tion of MSCs into neuronal cells through Wnt/β-catenin and Ca2+ signal pathway.

Animals ; Cell Differentiation ; drug effects ; Glucosides ; pharmacology ; Glycogen Synthase Kinase 3 ; Lipoproteins, LDL ; Low Density Lipoprotein Receptor-Related Protein-6 ; Mesenchymal Stromal Cells ; physiology ; Mice ; Neurons ; Phenols ; pharmacology ; Phosphopyruvate Hydratase ; RNA, Messenger ; Signal Transduction ; Wnt Signaling Pathway ; physiology ; beta Catenin ; metabolism

OBJECTIVE:To explore the reasons,occurrence mechanisms,as well as prevention methods for complications following cerebrovascular stent implantation.METHODS:A computer-based online search was performed by the first author.The databases of Medline and CNKI were searched with year's limitation of 1989-2009.According to the inclusive and exclusive criteria,the documents were screened,collected and evaluated from the following aspects:treating progress of cerebrovascular stent implantation;category and biocompatibility of cerebrovascular stent;as well as occurrence and prevention methods for complication following cerebrovascular stent implantation.RESULTS:A series of complications,such as carotid sinus response,hyper-perfusion syndrome,cerebral anglo spasm,bleeding at puncture locus,thrombosis,restenosis,as well as cerebral ischemia,would occur following cerebrovascular stent implantation.The complications were difficult to eliminate,but should be avoided by selecting correct implanting cases,elevating operator's proficiency,enhancing understanding of complications,obeying perioperative management,as well as correctly and in-time treatment.Polymer stent,coating stent,and drug eluting stent presented superior biocompatibility to metal stent,which could prevent restenosis following implantation.CONCLUSION:Cerebrovascular stent implantation is one of the main treatments for cerebrovascular disease.Polymer stent,coating stent,and drug eluting stent exhibit excellent biocompatibility.The complications associate to stent implantation are preventable and remediable via sufficient preoperatively preparation,exactly operation and perioperative management.

Aim To observe the changes of diaphragm contractility and cytoskeletal proteins titin,nebulin and sarcoplasmic reticulum Ca~(2+)-ATPase gene expressions in adriamycin-induced cytotoxicity in rats.Methods The animal models of diaphragm damage were duplicated by injecting adriamycin into abdominal cavity one time.Forty male sprague-dawley rats were randomly divided into four groups(n=10):Three groups received adriamycin in low,middle and high dosage(10,20 and 40 mg·kg~(-1))respectively.Meanwhile,the normal saline was given to rats in control groups.Three days later,these rats were killed,and the diaphragm was removed by thoracotomy.The diaphragm contractility was assessed in isolated diaphragm strips perfusion by these paramemters including peak twitch tension(Pt),maximum tetanic tension(Po),time to peak contraction(CT),half relaxaion time(1/2RT),maximal rates of contraction(+dt/dt_(max))and maximal rates of relaxation(-dt/dt_(max)).The expressions of titin,nebulin and sarcoplasmic reticulum Ca~(2+)-ATPase(SERCA)at mRNA level were detected by RT-PCR analysis.Results In contrast to those in control group,Po,Pt,±dt/dt_(max) in the adriamycin group were lower(P<0.01);CT,1/2RT in the adriamycin group increased significantly(P<0.01).The levels of titin,nebulin and SERCA gene expressions in middle-dose group were lower than those in control group(P<0.01).Conclusions The mRNA levels of titin,nebulin and SERCA of diaphragm are down-regulated in adriamycin-induced cytotoxicity in rats.It may be associated with the decline of diaphragm contractility.

Aim To observe the effects of liver cirrho-sis on the expression of transforming growth factor-β1 ( TGF-β1 ) and ColⅠin rat myocardium and interven-tion of erythropoietin ( EPO ) . Methods Thirty-six male Sprague-Dasley rats were randomly divided into three groups:control group, liver cirrhosis group and EPO group, then the cardic hemodynamic parameters in vivo and levels of serum lactate dehydrogenase ( LDH ) as well as creatine kinase isoenzyme ( CK-MB) were measured. With Masson′s trichrome stain, changes of collagen formation of myocardial tissue in different groups were observed. Also the mRNA ex-pressions of TGF-β1 and ColⅠin myocardium were de-tected by RT-PCR. Results In contrast to control group, rats in liver cirrhosis group showed a decline in systolic and diastolic function of left ventricule, rising myocardial enzyme, a distinct increase of cardiac colla-gen deposition, as well as an elevation of TGF-β1 and ColⅠmRNA expressions. In contrast to liver cirrhosis group, rats in EPO group demonstrated an improve-ment in systolic and diastolic function of left ventricule as well as in cardiac collagen deposition, and a de-crease in both myocardial enzyme and TGF-β1 and ColⅠmRNA expressions. Conclusion Liver cirrhosis can lead to the changes of myocardial structure and function in rats,and it can accelerate myocardial inter-stitial fibrosis; EPO can protect the myocardial injury in liver cirrhosis rats.

Objective To observe the expression of neural nicotinic acetylcholine receptor subunit α3 (α3nAChR) and extracellular regulated protein kinases (ERK1/2),c-Jun N-terminal kinase (JNK),p38 kinases of mitogen-activated protein kinase (MAPK) pathway in human neuroblastoma cell line SH-SY5Y overexposed to fluoride,and try to investigate the molecular mechanism of cell damage caused by overexposure of fluoride.Methods The SH-SY5Y cell with low expression of α3nAChR suppressed by silence interference RNA served as α3nAChR silence group;the normal SH-SY5Y cell served as control group,and the effect of silencing of αt3nAChR gene in SHSY5Y was detected by Western blotting and real-time PCR;SH-SY5Y cell was treated with different concentrations of fluoride (0.000,0.005,0.050,0.500,1.000,2.500,5.000 mmol/L),the safe concentration of fluoride in SHSY5Y cell was detected by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay;the SH-SY5Y cell of control group and α3nAChR silence group were treated with 4.000 mmol/L fluoride for 0,4,8,12,24,36,48 h according to the results of MTT assay;the expression of ERK1/2,JNK,p38 kinases of MAPK pathway in SH-SY5Y at protein levels was measured by Western blotting.Results The expression of α3nAChR mRNA (0.04 ± 0.03) and protein (12.0 ± 2.5) in α3nAChR silence group was decreased significantly compared with those of control group (1.00 ± 0.11,100.0 ± 11.3,t =24.58,28.80,all P ＜ 0.05).The viability of SH-SY5Y cell treated with 5.000 mmol/L fluoride (0.53 ± 0.15) was decreased significantly compared with that of SH-SY5Y cell treated with 0.000 mmol/L fluoride (1.05 ± 0.05,P ＜ 0.05).The increased expression of phospho-ERK1/2 was found in α3nAChR silence group and control group incubated with fluoride with time prolonged,and the expression of phospho-ERK1/2 increased significantly at time points 24,36 and 48 h (188.33 ± 7.33,200.00 ± 10.01,213.33 ± 11.55;125.33 ± 5.69,136.00 ± 4.52,155.33 ± 6.51) compared to 0 h in the same groups (100.00 ± 0.00,100.00 ± 0.00,all P ＜ 0.05),and the expression of phospho-ERK1/2 was higher significantly in α3nAChR silence group than those of control group (t =9.26,7.63,5.72,all P ＜ 0.05);no change of expression of total-ERK1/2 in the two groups was found with the passage of time.The gradually increased expression of phospho-JNK was found in α3nAChR silence group and control group,among which,the expression of phospho-JNK in o3nAChR silence group at time points 12,24,36 and 48 h (154.00 ± 6.25,149.00 ± 5.57,156.00 ± 6.08,141.67 ± 2.52) and in control group at 8,12,24,36,48 h (133.33 ± 10.69,173.00 ± 4.00,175.00 ± 11.79,200.67 ± 11.93,200.33 ± 18.58) was compared to those at 0 h in the same groups (100.00 ± 0.00,100.00 ± 0.00),and the difference was significant (all P ＜ 0.05);the higher expression of phospho-JNK was found in α3nAChR silence group other than control group at 8,12,24,36,48 h (t =-4.28,-5.02,-2.89,-8.33,-6.18,all P ＜ 0.05);no change of expression of total-JNK was found in the two groups (P ＞ 0.05).The increased expression of phospho-p38 was detected in control group at time points 24,36 and 48 h (120.33 ± 4.51,122.00 ± 7.55,119.67 ± 7.57) compared to 0 h in the same groups (100.00 ± 0.00,all P ＜ 0.05),and the expression of phospho-p38 was significantly higher than that in α3nAChR silence group at the same time points (93.33 ± 9.61,94.00 ± 5.01,98.33 ± 5.69,t =-4.01,-6.73,-5.59,all P ＜ 0.05);no change of expression of total-p38 was found in the two types of SH-SY5Y cells treated with fluoride (P ＞ 0.05).Conclusion When SH-SY5Y cells are exposed to fluoride;activation of ERK1/2 may be not depend on α3nAChR;α3nAChR may have protected the cell from apoptotic injury caused by activation of JNK pathway,and the activation of p38 may be depend on nAChRα3.