Unusual dTDP-sugars are key intermediate in many pathogenic bacteria. In this study, negative-ion electrospray tandem mass spectrometry (ESI-MS-MS) with collision-induced dissociation (CID) was used to study the fragmentation characteristics of six unusual nucleotide diphosphate sugars. The results indicated the major fragment of the six unusual nucleoside sugars observed in the ESI-MS-MS spectra resulted from cleavage of diphosphate moiety and their characteristic fragment ions at m/z 401, 383, and 321, correspond to [TDP-H] together with fragment ions resulting from the loss of water and phosphate moiety, respectively. Furthermore, 4-position substituted change of unusual sugar rings affected the stability of two important characteristic fragment ions of [glycosyl-1"-PO3](-) and [glycosyl-1"-P2O6](-).

BACKGROUND: Hydroxyapatite has favorable biocompatibility, can protect pulp tissue and promote the formation of osteoid dentin and the concrescence of pulp tissue. However, hydroxyapatite has no capability of anti-infection. Increasing scholars deem that antibacterials should be added with the hydroxyapatite during the treatment of vital pulp conservation to elevate curative effects.OBJECTIVE: To observe the curative effects of self-solidifying hydroxyapatite/norvancomycin composite as pulp capping material and to make a comparison with calcium hydroxide.DESIGN, TIME AND SETTING: The present randomized controlled observation experiment was performed at the General Dental Clinic, the Ninth People's Hospital, Shanghai Jiao Tong University Medical College between January 2004 and June 2005.PARTICIPANTS AND MATERIALS: A total of 60 patients (60 teeth) that suffered from deep caries or pulp exposure, could return visit on time, and agreed to sign informed consents were selected for this study. These patients comprised of 28 males and 32 females, aged 9-40 years. Diagnosis criteria: Teeth with food impaction pain and/or caloric stimulation pain which can relieve after stimulation removal; in addition, with no spontaneous pain, radiating pain, and hypnalgia. Self-solidifying hydroxyapatite/2.5% norvancomycin composite were prepared in the Department of Dental Material, Shanghai Second Hospital. Self-hardening calcium hydroxide was provided by Dentsply Company, USA.METHODS: All 60 patients were randomly divided into an experimental group and a control group, with 30 patients (30 teeth) per group. Self-solidifying hydroxyapatite/2.5% norvancomycin composite and self-hardening calcium hydroxide were applied as pulp capping agents in the experimental and control groups, respectively. Pulpal tissue reactions were assessed after 8 weeks. Teeth with normal response were restored permanently, and the others were given root canal treatment.MAIN OUTCOME MEASURES: Pulpal tissue reaction of patients.RESULTS: In the experimental group, one case showed vague pain after 1-week pulp capping and received root canal therapy, with success rate of 97%. In the control group, two cases presented with vague pain after 3-day and 1-week pulp capping, respectively, and also received root canal therapy, with success rate of 93%.CONCLUSION: Self-solidifying hydroxyapatite/norvancomycin composite acquires a high success rate of pulp capping, with curative effects similar to calcium hydroxide, it is a good pulp capping agent for vital pulp preservation.

Objective To investigate the correlation between transformational leadership style and nurses' job satisfaction in emergency department.Method The survey was done among 168 emergency department nurses from 4 first class hospitals in Guangzhou by the demographic information,multifactor leadership questionnaire and Chinese nurses' job satisfaction scale to investigate the status of transformational leadership style perceived by nurses and nurses' job satisfaction in the emergency departments.Results The score of transformational leadership style perceived by the nurses in the emergency department was (50.60±14.40) and jop satisfaction was (79.80±13.30).The transformational leadership style was positively correlated with nurses' job satisfaction (P＜0.01).Conclusions The transformational leadership style is middle-high level.The nurses' job satisfaction is at low level,Nursing managers should play an active role in transformational leadership style to enhance nurses' job satisfaction in emergency departments.

BACKGROUND:Mesenchymal stem cel s (MSCs) can be differentiated into vascular endothelial cel s to construct ideal blood vessel grafts in vitro that have wide prospective utility in the clinical treatment of ischemic diseases, vascular engineering and regeneration medicine.
OBJECTIVE:To review the recent research progress and related issue in biological characteristics of MSCs as wel as differentiation of MSCs isolated from different sources into vascular endothelial cel s.
METHODS:The first authors retrieved PubMed, Sciencedirect and Medline databases for relevant articles published from January 2000 to June 2015. The key words were“mesenchymal stem cel s;vascular endothelial cel;cel differentiation”in English. Initial y, 156 articles were retrieved, and final y 51 articles were included in result analysis.
RESULTS AND CONCLUSION:The MSCs sources are abundant. The research about bone marrow-derived MSCs is the earliest and maximum, but with the increasing donor age, their proliferation and differentiation ability decreases. MSCs from umbilical cord, placenta and amniotic membrane are easy to obtain, and meanwhile both neonatal and maternal does not feel any pain and psychological burden. Given these, these cel s are more acceptable for recipients, and there are no ethical, moral and legal disputes. MSCs from the umbilical cord blood are abundant with weak cel immunogenicity and low viral and bacterial contamination probability. However, the clinical application of amniotic fluid marrow-derived MSCs is limited because of its sampling methods.

Objective A high performance liquid chromatographic (HPLC) method was established for the simultaneous determination of xylitol and L-xylulose in fermentation broth.Methods The chromatographic conditions were as follows:C18 column (250 mm ×4.6 mm) with the temperature 35℃, acetonitrile-water (85∶15,v/v)as mobile phase with the flow rate of 0.8 mL/min.Xylitol was detected by refractive index (RI) detector at 33℃and L-xylulose was determined by ultraviolet ( UV) detector at 210 nm at room temperature.Results This method showed good linearity over the range from 0.50~30.00 g/L with a correlation coefficient of 0.9995 for xylitol and 0.30~30.00 g/L with a correlation coefficient of 0.9986 for L-xylulose. Moreover, the limit of quantification (LOQ) for xylitol and L-xylulose were 0.58 and 0.40,respectively.The limit of determination (LOD) for xylitol and L-xylulose were 0.18 and 0.15,respectively.The relative standard deviations (RSDs) of intraday and interday for xylitol were less than 0.64%and 0.80%,respectively.The intraday and interday RSDs for L-xylulose were less than 0.31%and 0.59%.The recoveries of xylitol and L-xylulose in fermentation broth were between 99.00%-101.00%.Conclusion There was no interference from other constitutes in the fermentation broth by this method.The methods were suitable for the simultaneous determination of the substrate xylitol and the product L-xylulose in fermentation process.

Background:As an important catalytic subunit of telomerase,human telomerase reverse transcriptase (hTERT)plays an important role in the development and progression of many cancers including gastric cancer.It has been reported that several single nucleotide polymorphisms (SNPs)of hTERT had varying degrees of association with risk of neoplasms. Aims:To study the correlation between SNPs of hTERT rs2853676 and rs2853677 and susceptibility to gastric cancer. Methods:Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was used to detect the genotypes of rs2853676 and rs2853677 of hTERT in 297 gastric cancer patients,105 atrophic gastritis and 402 controls. Helicobacter pylori (Hp)infection was detected by pathological examination and 13 C-urea breath test.Results:Frequency of AA genotype of rs2853676 was significantly higher in gastric cancer group when compared with control group (15.2%vs.6.5%,P =0.01).The risk of gastric cancer in AA genotype carriers increased 2.47-fold (95% CI:1.46-4.16) when compared with GG carriers.No significant differences in the frequencies of CC,TC and TT genotypes of rs2853677 were found among gastric cancer patients,atrophic gastritis patients and controls.Hp infection rates in atrophic gastritis group and gastric cancer group were significantly increased than those in controls (64.8%,56.9% vs.40.3%,P all <0.01),OR were 2.73 (95% CI:1.74-4.26),1.96 (95% CI:1.44-2.67),respectively.Logistic regression analysis showed that there was no significant interaction between Hp infection and gene mutation.Conclusions:Polymorphism of hTERT gene rs2853676 may play a role in susceptibility to gastric cancer,and Hp infection may not be involved in the increase of risk of gastric cancer caused by hTERT gene polymorphism.

Objective To develope energic spectrum of super-large solar particle events (SPE),human body model and a Monte Carlo method for estimating the organ dose of astronauts in SPE without the shielding of geomagnetic field. Methods A voxel-based human phantom and shielding model of spacecraft were developed and the Monte Carlo program was compiled and applied to calculate the doses of astronaut's organs with the transport protons of the spectra of super-large SPEs in 1956 and 1972, normalized by the proton fluence for energy greater than 30 MeV. Results The Monte Carlo program was developed successfully and the organ dose under different shielding thickness were also calculated with the program in the normalized spectra of SPEs in 1956 and 1972 without the effects of geomagnetic field. They were similar with prior studies. Conclusion The results are reliable by the comparison with other calculations of prior researchers. Exposure to super-large SPE without the shielding of geomagnetic field would result in a very large organ absorbed dose and may be very danger for manned spaceflight.

With the development of modem clinical medical engineering,especially some large medical equipment,medical engineering section needs more talents in management and maintenance profession.Aiming at problems in the section construction,some viewpoints and suggestions are put forward.It is expected that the leadership could attach importance to medical engineering section,make good use of the talents and lay solid foundation for the development of hospitals.

In order to adapt to social development and medical units of the high status of medical disputes,clinical education should focus on boosting up the concept of the legal system, strengthening the practice training,enhancing professional ethics and medical ethics education,and improving the doctor-patient communication and so on. Objective is to improve the overall quality of stomatological students,cultivate a complex stomatological talent with solid basic skills and broad knowledge.

Objective To study the effects of PDTC on cholesterol induced C-reactive protein gene expression in L-02 cell line.Methods Human hepatocyte cell line L-02 was cultured in vitro;growth-arrested cells were divided into 3 groups,cholesterol group,PDTC+cholesterol group and control group.After 48 h incubation,western blot and immunoturbidimetry assays were carried out to detect intracellular and secreted C reactive protein expression.Results Cholesterol stimulated CRP gene expression in L-02(P