Objective:To establish an in vitro root canal model infected by Enterococcus faecalis and to observe the morphology, distribution and relative position of Enterococcus faecalis in infected root canals.Methods: Ten human healthy premolars extracted for orthodontic reasons were collected. Following sterilization , a total of 5 specimens were aseptically transferred to separate Eppendorf tubes containing 1. 5 mL brain-heart infusion broth (BHI) inoculated with 0.1 mL Enterococcus faecalis suspension that had been adjusted to Mcfarland 5, and were incubated at 37℃ for 21 days. The other 5 specimens were as controls. The roots of all specimens were then split into two halves along the mesiodistal axis. One half was processed with light microscopic ( Brown & Brenn stain) to check the bacteria in dentinal tubules, and the other was observed with SEM to investigate the bacterial status in infected root canals. Results: Enterococcus faecalis could penetrate into the dentinal tubules about 330-1 000μm. A dense bacterial aggregation composed of Enterococcus faecalis and amorphous matrix was observed in the apical third of the root canals, whereas Enterococcus faecalis were seen free-floating or planktonic in the crown and middle third of the root canals . No microorganisms were found in the root canals of the controls. Conclusion:Enterococcus faecalis could form bacterial biofilm on the root canal walls and penetrate into the dentinal tubules. The in vitro model designed was simple, and had good practicability to make a further comparative evaluation of various antimicrobial methods in the reduction of intracanal bacteria.

Objective:To establish an in vitro root canal model infected by Enterococcus faecalis and to observe the morphology,distribution and relative position of Enterococcus faecalis in infected root canals.Methods: Ten human healthy premolars extracted for orthodontic reasons were collected.Following sterilization,a total of 5 specimens were aseptically transferred to separate Eppendorf tubes containing 1.5 mL brain-heart infusion broth(BHI) inoculated with 0.1 mL Enterococcus faecalis suspension that had been adjusted to Mcfarland 5,and were incubated at 37 ℃ for 21 days.The other 5 specimens were as controls.The roots of all specimens were then split into two halves along the mesiodistal axis.One half was processed with light microscopic(Brown & Brenn stain) to check the bacteria in dentinal tubules,and the other was observed with SEM to investigate the bacterial status in infected root canals.Results: Enterococcus faecalis could penetrate into the dentinal tubules about 330-1 000 ?m.A dense bacterial aggregation composed of Enterococcus faecalis and amorphous matrix was observed in the apical third of the root canals,whereas Enterococcus faecalis were seen free-floating or planktonic in the crown and middle third of the root canals.No microorganisms were found in the root canals of the controls.Conclusion: Enterococcus faecalis could form bacterial biofilm on the root canal walls and penetrate into the dentinal tubules.The in vitro model designed was simple,and had good practicability to make a further comparative evaluation of various antimicrobial methods in the reduction of intracanal bacteria.

Objective To observe the effect of different ways of balloon catheter dilation techniques on cricopharyngeal achalasia and its mechanisms.Methods Thirty patients with deglutition disorder after brain stem infarction,whose cricopharyngeal achalasias were proven by videofluoroscopic swallowing study(VFSS),were randomly divided into three groups: No.14 conventional catheter group A,No.14 modified bicavitary silica-gel catheter group B and No.22 conventional catheter group C with 10 cases in each group,respectively.All the patients of 3 groups received multiple times corresponding balloon catheter dilatation per nasal or per os(No.22 conventional catheter group C only per os).Results After an average of 30 d of balloon catheter dilatation,the level of dysphagia and VFSS evaluation of all patients improved significantly(P ＜ 0.05).However,the No.14 conventional catheter group A and No.22 conventional catheter group C improved to a greater extent than No.14 modified bicavitary silica-gel catheter group B(P ＜ 0.05).The saccule perimeter,saccule diameter and saccule intracapsular pressure of No.14 conventional catheter group A and No.22 conventional catheter group C increased significantly(P ＜ 0.05)when compared to those of No.14 modified bicavitary silica-gel catheter group B,but there was no significant diffference beween No.14 conventional catheter group A and No.22 conventional catheter group C(P ＞ 0.05).Conclusions The balloon catheter dilation technique can significantly improve swallowing function of deglutition disorders patients with cricopharyngeal achalasia after brain stem infarction,which is related positively to saccule diameter and saccule intracapsular pressure.

Objective To observe the influence of transplanting neural stem cells (NSCs) on angiogenesis in rats with spinal cord injury (SCI).Methods The Allen's method was used to create SCI models in sixty adult Sprague-Dawley (SD) rats.They were then randomly classified into a control group which received injections of phosphate buffered solution (PBS) and an NSC group which received injections of NSCs via the tail vein,with 30 rats in each group.Another group of 30 similar rats without SCI received injections of NSCs via the tail vein as the normal group.Each rat was evaluated before transplantation and at days 7 and 14 post-transplantation using the Basso,Beattie and Bresnahan (BBB) scale for testing hindlimb function.After sacrifice,the distribution of yon Willebrand factor (vWF) in both groups was determined by immunofluorescence,and Western blotting was used to detect vascular endothelial growth factor (VEGF) protein.Results The average BBB score of the normal group was 21 at every time point.Before transplantation,the BBB scoresof the control and NSC groups were both 0,however they increased over time.At day 7 post-transplantation,the BBB scores showed no significant difference between the control group and the NSC group.At day 14 post-transplantation,the average BBB score of the NSC group was significantly higher than that in the control group.At days 7 and 14,the counts of vWF-positive cells in the normal group were significantly higher than in the control and NSC groups.VEGF protein expression in the normal group was significantly lower than in the NSC and control groups.Conclusions NSC transplantation may promote angiogenesis after spinal cord injury and improve motor function by inducing the expression of VEGF.

Administration, Cutaneous ; Bronchopneumonia ; drug therapy ; Cefoperazone ; therapeutic use ; Child, Preschool ; Drug Therapy, Combination ; Drugs, Chinese Herbal ; administration & dosage ; Female ; Humans ; Infant ; Infusions, Intravenous ; Male

Objective To explore the change of the pre-swallow peak pressure of upper esophageal sphincter (UES) in patients with post-stroke cricopharyngeal achalasia,and investigate the effect of pre-swallowing peak UES pressure on swallowing function by quantitative analysis.Methods Fifty-seven stroke patients with cricopharyngeal achalasia were recruited and divided into balloon dilation group,combined training group and routine swallowing training group with 19 patients in eachp.All the three groups accepted routine swallowing training.In addtion,the routine swallowing training group and balloon dilation group accepted larynx elevation training and balloon dilation training,respectively,while the combined training group accepted larynx elevation training and balloon dilation training simultaneously.The pre-swallow peak UES pressure was measured by using PC polygraph high rate gastrointestinal dynamical detection system (PC Polygraf HR,CTD-synectics,Sweden) before and after 8 weeks of treatment.The swallowing function was assessed using swallowing function classification and water swallowing test.Results Before treatment,there was no significant difference among the 3 groups in terms of the pre-swallow peak UES pressure,swallowing function classification,water swallowing test and VFSS (P ＞ 0.05).After treatment,pre-swallow peak UES pressure,swallowing function classification,water swallowing test and VFSS of the balloon dilation group and combined training group improved significantly compared with those before treatment (P ＜ 0.05),and the improvement in the combined training group was to a significantly better extent than in the balloon dilation group(P ＜O.05).Conclusion Balloon dilation and larynx elevation training plus routine swallowing training can increase pre-swallow peak UES pressure,decrease the UES resting pressure of stroke patients with cricopharyngeal achalasia,which is of great importance for their recovery.

Objective To observe the surface electromyographic characteristics of the bilateral submen-tal muscles in dysphagia secondary to unilateral brainstem stroke. Methods A total of 25 subjects were recrui-ted. There were 8 stroke patients with dysphagia secondary to a left brainstem stroke and 7 stroke patients with dysphagia secondary to a right brainstem stroke. There were also 10 healthy controls matched in age and gender. The duration and peak amplitude of the submental muscle when swallowing 5 ml of warm water were recorded u-sing a surface electromyograph. Results The average amplitude of the left submental muscle in patients with a left brainstem stroke was significantly longer than that of those with a right brainstem stroke, but no significant differences in average duration were observed. Conversely, the amplitude of the right submental muscle in pa-tients with a right brainstem stroke was significantly longer than that of those with left brainstem stroke, but again there were no significant differences in duration. No significant differences were observed among the healthy con-trols. The amplitude and duration of both the affected and healthy sides of the patients were of course significantly longer or stronger than those of the healthy controls. Conclusion The swallowing function of the bilateral sub-mental muscles may be impaired among unilateral stroke survivors with dysphagia. The damage on the affected side is more severe than on the opposite side.

The metabolic characteristics of ligustrazin (TMPz) in liver microsomes were investigated in the present study. The reaction phenotyping of TMPz metabolism was also identified by in vitro assessment using recombinant human cytochrome P450 enzymes (CYP) and UDP glucuronosyltransferases (UGT). TMPz was incubated at 37 degrees C with human (HLM) and rat liver microsomes (RLM) in the presence of different co-factors. The metabolic stability and enzyme kinetics of TMPz were studied by determining its remaining concentrations with a LC-MS/MS method. TMPz was only metabolically eliminated in the microsomes with NADPH or NADPH+UDPGA. In the HLM and RLM with NADPH+UDPGA, t1/2, K(m) and V(max) of TMPz were 94.24 +/- 4.53 and 105.07 +/- 9.44 min, 22.74 +/- 1.89 and 33.09 +/- 2.74 micromol x L(-1), 253.50 +/- 10.06 and 190.40 +/- 8.35 nmol x min(-1) x mg(-1) (protein), respectively. TMPz showed a slightly higher metabolic rate in HLM than that in RLM. Its primary oxidative metabolites, 2-hydroxymethyl-3, 5, 6-trimethylpyrazine (HTMP), could undergo glucuronide conjugation. The CYP reaction phenotyping of TMPz metabolism was identified using a panel of recombinant CYP isoforms (rCYP) and specific CYP inhibitors in HLM. CYP1A2, 2C9 and 3A4 were found to be the major CYP isoforms involved in TMPz metabolism. Their individual contributions were assessed b) using the method of the total normalized rate to be 19.32%, 27.79% and 52.90%, respectively. It was observed that these CYP isoforms mediated the formation of HTMP in rCYP incubation. The UGT reaction phenotyping of HTMP glucuronidation was also investigated preliminarily by using a panel of 6 UGT isoforms (rUGT). UGT1A1, 1A4 and 1A6 were the predominant isoforms mediated the HTMP glucuronidation. The results above indicate that the metabolism of TMPz involves multiple enzymes mediated phase I and phase II reactions.
Animals ; Cytochrome P-450 CYP1A2 ; metabolism ; Cytochrome P-450 CYP2C9 ; metabolism ; Cytochrome P-450 CYP3A ; metabolism ; Cytochrome P-450 Enzyme Inhibitors ; Cytochrome P-450 Enzyme System ; metabolism ; Drug Interactions ; Glucuronosyltransferase ; metabolism ; Humans ; Ligusticum ; chemistry ; Microsomes, Liver ; enzymology ; NADP ; metabolism ; pharmacology ; Pyrazines ; metabolism ; pharmacokinetics ; Rats ; Uridine Diphosphate Glucuronic Acid ; metabolism ; pharmacology

Objective To explore the application of videofluoroscopic swallowing study (VFSS) in the treatment of dysphagia post-stroke. Methods Eighty patients were assigned into control and treatment groups. Both groups accepted routine drug treatments and physical therapy, and all patients underwent VFSS on the 1 st and 28th day of the study. The patients in the treatment group accepted weekly VFSS in addition, and their swal-lowing training schedules were formulated according to the VFSS assessment results. Water drinking tests and de-glutition disorders were adopted to assess the patients' swallowing function before and after therapy. Results In treatment group, where the therapy schedule was adjusted using VFSS every week, the adjustment proportion at the 2nd, 3rd and 4th week was 20.6% , 40.7% and 15.8% , respectively. Before treatment there was no difference between the two groups with regard to water drinking, deglutition or VFSS scores. After training the water drinking and deglutition results and the time for iodine to transit the oral cavity and pharynx all improved significantly in both groups. The improvements in the treatment group were significantly greater than in the con-trol group. Conclusions Swallowing training based on videofluoroscopic assessment can significantly alleviate post-stroke dysphagia.

Objective To assess the effect of stromal cell-derived factor 1 (SDF-1) on the migration of neural stem cells and recovery of lower limb function after spinal cord injury (SCI).Methods A modified version of Allen's method was used to establish a SCI model in each of 96 adult male Sprague-Dawley rats.They were then randomly divided into group A which received an injection of phosphate buffer solution,group B which received an injection of neural stem cells,group C which received a combination of SDF-1 and neural stem cells,and group D which received AMD3100 and neural stem cells 7 days after the modeling.The functioning of the hind limbs of all of the rats was assessed on the 7th,14th,21st and 28th day after the modeling.The rats were then sacrificed and frozen sections of their spinal cords were stained with hematoxylin-eosin (HE) and marked with CM-Dil under fluorescent light.Results An accumulation of fluorescing cells were observed in spine cords from both group B and C,with the counts of group B [(23.6 ±3.7),(18.9 ±5.6)and(15.2 ±4.3) respectively] at the day 14,21 and 28 after modeling significantly smaller than those of group C [(27.4 ± 4.7),(20.4 ± 5.2) and (18.3 ± 3.9) respectively].During the same period of time,the average BBB scores of groups B and C were significantly better than those of groups A and D.Moreover,the average score of group C was significantly higher than group B's at all time points.Conclusions Transplanted neural stem cells can migrate to the injured site,surviving and differentiating to promote the recovery of limb function in rats with spinal cord injury.SDF-1 can promote that migration and proliferation.Moreover,CXCR4 receptor's antagonist AMD3100 can significantly hinder neural stem cells' migration to the injured site on the spinal cord.