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 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.

Aim To observe the influences of ginsenoside Rg1 on the spontaneous contraction of small intestine smooth muscle of rabbits in vitro and explore the mechanism.Methods With the isothermal perfusion of small intestine in vitro,the influences of ginsenoside Rg1 on the spontaneous contraction of small intestine was observed and the mechanism of ginsenoside Rg1 was studied.Results Ginsenoside Rg1 reduced the amplitude of contraction of small intestine smooth muscle in rabbits in a dose-depended manner.Bay K8644 and nitro-L-arginine methylester(L-NAME)could completely block the inhibition of ginsenoside Rg1 on the contraction of small intestine smooth muscle.Ginsenoside Rg1 inhibited the intracellular calcium-depended contraction induced by rynodine in the Ca2+ free Tyrode's solution.Conclusions Ginsenoside Rg1 inhibits the contraction of small intestine smooth muscle of rabbits in vitro.The mechanism may be related to increase NO concentration in small intestine smooth muscle so that it inhibits extracellular Ca2+ inflowing via cell membrane and intracellular Ca2+ releasing via sarcoplasmic reticulum.

Objective Clinical parenteral nutrition( PN) support still lacks in standards on some degree .This paper was to analyze the clinical application of PN support in our hospital in order to provide the basis for clinical rational drug use . Methods Random weighting method was applied to collect 5% hospitalized patients′information from each patient unit each month from April 2012 to March 2013 in Nanjing Gerneral Hospital of Nanjing Military Region .NRS-2002 nutrition risk screening was applied to eval-uate whether the patient needed PN support .Statistical analysis were carried out on patients supported with parenteral nutrition from department distribution, PN detailed components and distribution intervals of aII in one admixture non-protein calorie and nitrogen ra-tio. Results According to the survey, 393 patients had received PN support, including 217 cases′NRS score <3 and 176 cases′NRS score ≥3.General surgery department ranked the first in the cases of usingall in oneadmixture support.Among 133 cases receiving all in one admixture support, the course of 37 cases(27.82%) <7 d.The aII in one admixture non-protein calorie and ni-trogen ratio(100~150∶1) only took up 28.57%. Conclusion Although PN has got wide application in clinical departments, the rationality of prescription should be strengthened .Pharmacists should help doctors set up appropriate prescription from the aspect of pharmacy.

10.3969/j.issn.2095-4344.2013.23.026

Aim To investigate the effect of ginsenoside Rg1 on gut injury following intestinal ischemia reperfusion in rats and the possible mechanism.Methods By using rat model of intestinal I/R injury, 30 male SD rats were randomly divided into 3 groups(n =10 in each group):sham-operation group, I/R group(control group)and ginsenoside Rg1 group(treatment group).The contents of tumor necrosis factor α(TNF-α), interleukin-6(IL-6), malondialdehyde(MDA), the activity of superoxide dismutase(SOD)in intestinal mucosa were measured respectively.Chiu's count was used to assess the changes in intestinal pathological morphology.Results TNF-α, IL-6, MDA contents and the intestinal injury score in control group were significantly increased compared to those in sham-operation group, while SOD contents in control group were significantly decreased compared to sham-operation group.Inversely, TNF-α, IL-6, MDA contents and the intestinal injury score in treatment group were significantly decreased compared to those in control group, while SOD contents in treatment group were significantly increased compared to control group.Conclusion Pretreatment with ginsenoside Rg1 has protective effect on intestinal ischemia-reperfusion injury in rats, which may be attributed to decreased contents of TNF-α, IL-6, MDA and increased levels of SOD.

Objective To establish rabbit model of remnant carcinoma after RFA therapy, and to observe pathomorphological changes of remnant carcinoma in different time. Methods Forty-eight New Zealand white rabbits underwent ultrasound-guided percutaneous inoculation with VX2 carcinoma, then RFA therapy was performed to made models of remnant carcinoma. These models were averagely divided into 6 groups randomly (each n=8). Rabbits in each group was killed and pathologically observed before RFA and 1 d, 3 d, 1 week, 2 and 3 weeks after operation, respectively. Results The expression of MVD,VEGF and PCNA in remnant VX2 carcinomas tissues decreased significantly, but increased 2-3 weeks after RFA. The remnant VX2 carcinomas tissues were in inhibitory state 2 weeks after RFA. Conclusion The growth of remnant carcinoma could be inhibited in short term after RFA. Further therapy is necessary.

Tacrolimus exhibits varied individual pharmacokinetic and a narrow therapeutic window, resulting in difficulties in personalized medication.In order to improve the safety of tacrolimus in clinical application and its efficiency and rationality in clinical practice, many countries and regions in the world have issued a number of guidelines for tacrolimus application.However, these guidelines generally aim at particular disease and race, and have certain limitation.In this article, the guidelines were explicated and analyzed in detail.Moreover, an individual tacrolimus medication recommendation for Chinese population was summarized based on the latest research of tacrolimus pharmacogenomics and therapeutic drug monitoring so as to provide assistance for the rational use of tacrolimus.

Objective To investigate the correlation between tumor perfusion parameters and tumor volume and Child-Pugh classification in CT of hepatocellular carcinoma (HCC).Methods Fifty-six patients with hepatocellular carcinoma were selected to perform CT perfusion imaging.The parameters of the total tumor perfusion such as hepatic artery perfusion (HAP),portal vein perfusion (PVP)and hepatic perfusion index (HAPI)were calculated according to the degree of hepatic encephalopathy,albumin,bilirubin, clotting time,ascites for liver Child-Pugh classification.The relationship between the tumor or peritumoral perfusion parameters with tumor volume and Child-Pugh classification were analyzed.Results (1)There was no correlation between tumor or peritumoral perfusion with the tumor volume.(2)The difference of HAP,PVP and HAPI between the different Child-Pugh classification groups was statistically significant (P<0.000 1).(3)With the reduction of Child-Pugh classification,the tumor body HAP and HAPI values gradually decreased, while the PVP value increased gradually.Conclusion There is no correlation between the tumor volume of hepatocellular carcinoma with total tumor perfusion parameters.The differences in perfusion measurements between different Child-Pugh classification can intuitively and quantitatively reflect the reserve function of the liver.

Objective:To understand the attitudes of obstetricians and midwives towards the development of nurse practitioner in China.Methods:The phenomenological method in qualitative research was used to conduct semi-structured interviews with 24 medical staff in the third-A general hospitals and women and children's hospitals in Guangzhou and Dongguan City. The interview data were analyzed by Colaizzi's 7-step analysis method.Results:Four themes were extracted, namely, unanimous approval attitude, imperfect midwifery discipline and management system, insufficient independent practice capacity, low support and recognition in midwifery area.Conclusions:Obstetricians and midwives hold a positive attitude towards the development of midwifery nurse practitioner. At the same time,its development is restricted in many aspects. They can gradually develop midwife′s legislation, improve the management system, try some prescription rights, and increase the education and talents of midwifery subjects. Cultivation and promotion of social recognition will help gradually train midwifery nurse practitioner in China.