In response to problems from the development of multi-drug-resistant pathogenic bacteria,it is urgent to find new antimicrobials.Antimicrobial peptides(AMPs) are a kind of ideal new antimicrobials with the advantages including their potential for broad-spectrum activity,rapid bactericidal activity and low propensity for resistance development,and have a bright future.Alpha-helical antimicrobial peptides are a main kind of AMPs.The following features was reviewed and elucidated including the structure and activity relationship(SAR) from different aspects including the degree of helicity,hydrophobic moment,hydrophobicity,net positive charges and so on,and the application of SAR on the molecular design and improvement of AMPs.

Objective To synthesize 99Tcm- (hydrazinonictinamide- [Lys3] -bombesin) (tricine)(trisodium triphenylphosphine-3,3',3"-trisulfonate) ((HYNIC-[Lys3]-BBS) (tricine) (TPPTS)) and evaluate its biodistribution and binding capability with tumor tissue in Balb/c nude mice bearing human pancreatic cancer xenografts. Methods HYNIC was conjugated to the [Lys3] -BBS at pH = 9.0 with SnCl2 as reducing agent and both tricine and TPPTS as coligands for 99Tcm-labeling. 99Tcm-HYNIC-[Lys3]-BBS)(tricine) (TPPTS) was purified by Sep-Pak C18 cartridge and was analysed by HPLC. The radiochemical purity and radiolabeling yield were measured. The stability of 99Tcm-(HYNIC-[Lys3]-BBS) (tricine)(TPPTS) in serum, biodistribution (% ID/g) in the normal mice and imaging of the Balb/c nude mice bearing human pancreatic cancer xenografts in vivo were studied. Results The radiolabeling yield was (90 ±2)% and the radiochemical purity was over 95%. The radiochemical purity after 4 h in serum was over 85%. The distribution in normal mice showed rapid clearance from blood (the uptake was (0.07 ±0.01) %ID/g at 2 h postinjection). 99Tcm-(HYNIC-[Lys3]-BBS) (tricine) (TPPTS) was excreted mainly via the kidney with little radioactivity accumulation in the liver and gastrointestinal tract (the uptake of liver, stomach, intestine was (0.27 ±0.03), (0.06 ±0.03), (0.04 ±0.00) %ID/g at 2 h postinjection). Marked uptake of radioactivity was found in tumor tissue of the Balb/c nude mice bearing human pancreatic cancer with maximum T/NT ratio of 3.71 ± 0.57 at 2 h postinjection. Conclusions 99Tcm-(HYNIC-[Lys3]-BBS)(tricine) (TPPTS) can be easily prepared with high radiolabeling yield and radiochemical purity. The stability in serum and good biodistribution charateristics make it useful for the diagnosis of human pancreatic cancer with over-expression of the gastric-releasing peptide(GRP) receptor.

The tandem expression vector can effectively increase the expression level and structure stability of the target peptides(protein)with small size of molecular,and avoid toxicity towards host cell from some toxic peptides product,therefore,this approach is widely applied in biotechnology.The four construction methods of tandem expression plasmid including asymmetric and complementary cohesive ends,directional adapter,isocaudarners,and tandem expression cassette were reviewed in terms of protocol,characteristic and applicable field.In addition,selection principles from various construction methods of tandem plasmid were reviewed in terms of efficiency,accuracy and product cleavage.

Objective The aim of this study was to investigate the characteristic of regional cerebral glucose metabolism in patients with Wilson's disease (WD) using 18F-fluorodeoxyglucose (FDG) PET.Methods Thirteen WD patients and 12 normal controls were studied by brain 18F-FDG PET, and the data were analyzed by visual analysis, semi-quantification and statistical parametric mapping (SPM). The radioactivity ratios of lenticular nuclei, caudate, thalamus and cerebellum to cerebral cortex and the ratio of lenticular nuclei to caudate were calculated, respectively. SPSS 11.0 software for statistics was also used to analyze the data. Results In WD patients, radioactivity of lenticular nuclei and candate was significantly decreased compared with controls. The radioactivity ratios of lenticular nuclei and caudate to cerebral cortex in WD patients were both significantly lower than that in normal controls (0.95±0.05 vs 1.26±0.05, t =15, P < 0.05 ; 1.02±0.06 vs 1.17±0.05, t = 8, P < 0.05), and the ratio of lenticular nuclei to caudate in WD patients was significantly higher than that in normal controls (0.93±0.06 vs 1.09±0.06, t =9, P< 0.05). Conclusion As compared with normal controls, patients with WD had significantly decreased glucose utilization in the basal ganglia, especially in the lenticullar nuclei.

In the treatment of hypertensive crisis, the novel Rho kinase inhibitor DL0805-2 can rapidly lower systematic blood pressure, reduce pulmonary artery pressure, and has a significant protective effect on lung injury. This experiment intends to evaluate the efficacy of DL0805-2 against pulmonary arterial hypertension (PAH) and preliminarily reveals its underlying mechanism. Animal welfare and experimental procedures are in accordance with the provision of the Animal Ethics Committee of the Institute of Materia Medica, Chinese Academy of Medical Sciences. Sprague Dawley (SD) rats were randomly divided into DL0805-2 low, medium, and high dose groups (1, 3, and 10 mg·kg^-1), bosentan positive control group, model group, and blank control group. The drug was administered daily on the 7th day after model establishment by monocrotaline injection. On the 25th day of the experiment, relevant indicators were examined to observe the therapeutic effect of DL0805-2 on pulmonary hypertension. DL0805-2 significantly relieved the abnormal changes in the physiological parameters related to PAH induced by monocrotaline, including reducing right ventricular systolic pressure, alleviating cardiac damage caused by pressure overload, and reducing the levels of endothelin-1 and inflammatory factors in lung tissues. DL0805-2 also attenuated pulmonary arteries remodeling. It was preliminarily discovered that DL0805-2 exerts preventive and therapeutic effect on PAH through Rho-kinase pathway. Our results suggested that DL0805-2 had good therapeutic effects on monocrotaline-induced PAH rat model. It intervened early in the disease process, effectively prevented the development of the disease, and reduced the mortality of the diseased animals. The mechanism is related to Rho-kinase pathway.

Objective To develop and optimize a module for the automatic production of N-succinimidyl-4-[18F] fluorobenzoate (18F-SFB) that is used for further 18F labelling C2A domain of Synaptotagmin Ⅰ . The conjugated compound was applied for detecting the tumor apoptosis in rabbit model after chemotherapy. Methods GE TRACERlab and TRACERlab FXF-N modules were modified and programmed to automatically produce 18 F-SFB which was further analyzed by high performance liquid chromatography (HPLC).C2A-glutathione S transferase (GST) was conjugated with 18F-SFB (18F-FB-C2A-GST) and subsequently purified by HPLC. Two rabbits grafted with VX2 lung cancer were first treated with chemotherapy and then,37 MBq of 18F-FB-C2A-GST was administered via the auricular vein. Serial PET/CT imagings were performed at 0.5, 1 and 2 h post-injection respectively. Tumor apoptosis was examined by pathological study. Results The TRACERlab FXFoG and TRACERlab FXF-N modules were successfully adapted to synthesize18F-SFB, with the radiochenmical yield (76.41 ±4.00)% (n = 10), the corrected yield (45.43 ±5.90 ) % and the radiochemical purity about 95%. The whole procedure for labeling 18 F-SFB was about 87 min.From PET/CT imagings, significant uptake was found in the tumor after chemotherapy, but no obvious up-take was found in heart, lungs and liver. HE staining demonstrated large number of apoptotic bodies within the tumor tissues. Conclusions 18 F-SFB can be automatically synthesized. 18F-FB-C2A-GST might be useful for the detection of apoptosis in tumor after chemotherapy.

OBJECTIVETo prepare a drug-loading film using chitosan and carboxymethyl chitosan as the carrier materials for delivering matrine to oral ulcers.

METHODSMatrine-loading films using chitosan or carboxymethyl chitosan as the carrier materials were prepared by solution casting method and orthogonal experiment at room temperature. The mechanical properties, surface morphology and drug-loading capacity of the drug-loading film were characterized using tensile test, scanning electron microscopy (SEM), swelling test and in vitro drug release test.

RESULTSWhen the molecular weight of chitosan was 650 000 and the mass ratio of chitosan/glycerol was 1:1.4, the prepared film had the maximum mechanical strength and tensile modulus reaching 0.7875 MPa. SEM observation showed that matrine aggregated at the bottom of the drug-loading film with an asymmetrical distribution. The in vitro drug release test showed that the film had a high drug-loading capacity and a sustained drug release property. The duration of drug release from the drug-loading film was prolonged as the molecular weight of chitosan increased, reaching 23 h when the molecular weight of chitosan was 650 000. The duration of drug release was further increased to 108 h when the bottom of the drug-loading film was coated with a layer of 1% carboxymethyl chitosan.

CONCLUSIONThe matrix materials of the drug-loading film are natural, green, nontoxic and biodegradable, and the preparation of the film is simple without using large quantities of organic solvents. The novel drug-loading film can obviously prolong the duration of drugs release for better local drug delivery to oral ulcers in a sustained manner.

Alkaloids ; chemistry ; Chitosan ; analogs & derivatives ; chemistry ; Delayed-Action Preparations ; Drug Delivery Systems ; Drug Liberation ; Glycerol ; chemistry ; Microscopy, Electron, Scanning ; Quinolizines ; chemistry

OBJECTIVETo establish a probabilistic model for evaluation of dietary exposure to lead and construct age-related exposure centiles for the residents in Jiangsu.

METHODSLead contamination data were obtained from the national food contamination monitoring program during 2001 - 2006 and 2791 samples from 232 food products in Jiangsu were included. Food consumption data were from the national diet and nutrition survey conducted in 2002, including 3938 subjects in Jiangsu. A non-parametric probabilistic model using Monte Carlo simulation was applied to derive the intake distribution. The intake data was then analyzed using the LMS method, which constructs exposure percentiles adjusted for the median (M), the coefficient of variation (S) and the skewness (L) of the intake distribution.

RESULTSThe median and P(99) of the lead exposure for the residents in Jiangsu were 1.02 µg×kg(-1)×d(-) and 9.29 µg×kg(-1)×d(-1), respectively.6.38% of the total population showed to have a lead intake exceeding the tolerable limit, which for the urban and rural population were 4.31% and 7.06%, respectively. The exceeding rate for children of 2 - 10 years old from the urban and rural areas were 13.17% and 17.70%, respectively.

CONCLUSIONThere was a large variation in the lead exposure level of the population in Jiangsu; People in rural areas are in greater risk for higher lead exposure than urban people; The dietary exposure to lead for children and the high-end population was serious.

Child ; Child, Preschool ; China ; Environmental Exposure ; Food Contamination ; analysis ; Humans ; Lead ; analysis ; Risk Assessment

OBJECTIVETo investigate the relative factors for hidden blood loss (HBL) after primary total knee arthroplasty (TKA).

METHODSA retrospective study of 422 consecutive patients who underwent primary TKA between October 2007 and August 2009 was carried on. There were 60 male and 362 female patients with a mean age of 65.7 years. The HBL was calculated according to Gross formula. The effect of patient gender, age, body mass index (BMI), pre-operative diagnosis, unilateral or simultaneous bilateral TKA, tourniquet time, type of prosthesis, postoperative anticoagulation method and deep vein thrombosis (DVT) on the postoperative HBL were analyzed.

RESULTSThe HBL in patients underwent unilateral TKA was significantly lower than that in those underwent simultaneous bilateral TKA [(1284 ± 207) ml vs. (2248 ± 504) ml, P = 0.000]. Unvaried analysis showed that the HBL were associated with BMI, tourniquet time, prosthesis type and postoperative anticoagulation method. Multivariate linear regression analysis showed that the impact factors of postoperative HBL include BMI, tourniquet time and prosthesis type.

CONCLUSIONSBMI, bilateral simultaneous TKA, tourniquet time and intercondylar open prosthesis impact the HBL after primary TKA. However, the influence of gender, age, diagnosis, postoperative anticoagulation method and DVT on the HBL are not significant.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Arthroplasty, Replacement, Knee ; Female ; Humans ; Male ; Middle Aged ; Osteoarthritis, Knee ; surgery ; Postoperative Hemorrhage ; Regression Analysis ; Retrospective Studies ; Young Adult

Objective To evaluate the enhanced magnification endoscopy in the diagnosis of Barrett esophagus,and to explore the relationship between mucosal surface patterns and pathological epithelial types of Barrett esophagus.Methods Enhanced magnification endoscopy was performed 'after spraying 2%-3% acetic acid on the surface of distal esophagus in 40 Barrett esophagus patients.Mucosal specimen were biop- syed.Results According to the mucosal types of Toyoda in 2003,there were three mucosal types:Ⅰ dot pat- tern 7(17.5%),5 of 7(71.4%)fundie type,Ⅱ reticular pattern 24(60.0%),16 of 24(66.7%)fundic type,Ⅲ cerebroid/villous 9(22.5%),intestinal metaplasia or dysplasia.Conclusion Enhanced magnifi- cation endoscopy helps to identify areas with intestinal metaplasia and dysplasia,and is useful in the diagno- sis of Barrett esophagus.