BACKGROUND:When bone cement solidifies fast,the bone cement consistency will be decreased.resulting in difficulty in molding.DESIGN,TIME AND SETTING:Open experiment,performed in the Laboratory of Department of Materials,Lanzhou Jiaotong University between March 2005 and August 2006.gelatin were mixed with citric acid to produce hardening liquid.Then bone cement power and hardening liquid were mixed to form a paste,I.e.,bone cement.METHODS:Setting time of bone cement was determined using a Vicat apparatus.The compressive strength of bone cement at different proportions was tested using MTS-810 material tester.After 2 months of physiological saline soaking at 37℃.the microstructure of solidified bone cement was observed using scanning electron microscope.MAIN OUTCOME MEASURES:Setting time and compressive strength of bone cement,pH value of hydrated bone cement and the microstructure.RESULTS:After adding chitosan and gelatin in the hardening liquid.the consistency of the concoction obviously increased,the setting time became a little longer and the water-resistance of samples was enhanced.therefore the samples could be easily molded.But the compressive strength of the bone cement decreased a little.The pH value of the hydrated bone cement increased gradually with time and was close to the pH value of physiological saline at hour 24.The compressive strength of bone cement was achieyed at 24 hours and it almost did not change after 48 hours.the drawback of ceramic HA,including sintering and difficulties in shaping.It has the characteristics of simple-producing,easy application and low heat energy.

AIM: To prepare α-tricalcium phosphate (α-TCP)/calcium polyphosphate (CPP) fiber and to study the feasibility of CPP fiber to reinforce calcium phosphate bone cement composites. METHODS: Firstly,α-TCP powder was synthesized using chemical sediment method. Secondly, the α-TCP was mixed with CPP fiber according to different contents and lengths. Finally, bone cement was tempered with firming agent. Solidification time and mechanical property of the samples were measured. Microstructure of hardened sample was observed with scanning electron microscope. RESULTS: When the amount of CPP fibers was 10% and the length was 2 mm, the compressive strength reached 62.5 MPa and the rupture strength reached 12.4 MPa. Scanning electron microscope suggested that CPP fibers with great associativity were well distributed in bone cement. After immersing in Ringer fluid for two months, the CPP fibers did not biodegrade obviously and still had certain function to increase strength and toughness. CONCLUSION: To a certain extent, the CPP fiber can increase strength and toughness of bone cement. Furthermore, α-TCP/CPP composites have good mechanical properties and biocompatibility.

AIM: A new type of unsaturated poly (ester-amide) viz maleic anhydride-phthalic anhydride-propylene glycol-neopentylene glycol-hexane diamine copolymer was prepared by melt polycondensation and characterized.METHODS: To use it as biodegradable bone fixation polymer materials, the flexural strength of unsaturated poly (ester-amide) prepared under different heat treatment conditions was measured after depth cross-linking. The degradation and hydrolysis of the polymer were investigated in phosphate buffer (0.1 mol/L, pH7.4) at 37 ℃ and in 0.1 mol/L NaOH standard solution at room temperature.RESULTS: The results obtained indicate that increasing heat treatment time or temperature can dramatically increase the flexural strength of cross-linked unsaturated poly (ester-amide). The maximum flexural strength of the cross-linked polymer containing 50 wt% of cross-linker was 123 MPa. After degradation 3 months, the flexural strength of the cross-linked polymer that contained 50 wt% of cross-linker and was heated at 195 ℃ for 18 hours could maintain as high as 114.3 MPa.Heat treatment conditions and cross-linker content play an important role to control the mass loss of the cross-linked polymer during the hydrolysis. The polymer exhibits bulk erosion property.CONCLUSION: The preliminary results obtained suggested that the copolymer might be used as bone internal fixation material.

Objective To comparatively study the difference status of lymphocyte subsets and activated T lymphocyte between preoperation and intraoperation,and to investigate the influence of operation on lymphocyte subsets and their activation in the pa-tients with malignant tumors.Methods The lymphocyte subsets and their activated cells were determined in 42 cases of common malignant tumors by the flow cytometry.Results The levels of CD3 + ,CD4 + ,CD8 + cells during intraoperation were obviously de-creased compared with preoperation,the difference in CD3 + and CD4 + had statistical significance(P <0.05),while the difference of CD8 + had no statistical significance(P >0.05).NK,CD19 + ,CD3 + HLA-DR+ were significantly increased,the difference of NK and CD19+ had no statistical significance(P >0.05),while the difference with CD3 + HLA-DR+ had statistical significance(P <0.05). Conclusion The cellular immune function in the patients with malignant tumor is in inhibitory status.Operation makes the cellular immune function to be further injured.The stress responses of operation and trauma increase the expression of NK,CD19 and acti-vated T lymphocytes.It is suggested that the patients with malignant tumor should use the immune response modifier before opera-tion to enhance the cellular immune function for ensuring the effect of postoperative radiochemotherapy sequential treatment.

Objective To investigate the expression of PHF8(PHD-finger protein 8) in human hepatocellular carcinoma (HCC) and its clinicopathologic significance.Methods The expression of PHF8 in 60 hepatocellular carcinoma samples as well as their natched paraneoplastic tissues,and 15 normal liver tissues were evaluated by immunohistochemistry.Statistical methods were used to analyse the relationship between the expression of PHF8 and the clinicopathological features of these patients.Results The PHF8-positive expression rate in the HCC samples was 55.0％ and it was significantly higher than that in the paraneoplastic tissues and the normal liver tissucs (16.7％,6.7％,respectively,P＜0.05).The expression of PHF8 was closely related to tumor size,tumor nodular numbers,pathological differentiation and TNM-staging (P＜0.05 for all).The 5-year disease-free survival and overall survival in the PHF8-positive group was significantly lower than that in the negative group (P＜0.05).Conclusions PHF8 was overexpressed in HCC samples,and its expression was closely associated with HCC clinicopathological features and prognosis of the patients.

BACKGROUND: Nowadays, the scaffold for tissue engineering have low properties of physical mechanics, poor biocompatibility and has not free regulating degradation as matrix materials.OBJECTIVE: To develop a composite of scaffold for cartilage tissue engineering with higher porosity and good mechanical characteristic, biocompatibility and free regulating degradation as matrix materials.DESIGN, TIME AND SETTING: This experiment was conducted at the Research Institute of Engineering Materials, Lanzhou Jiaotong University from June 2006 to June 2008.MATERIALS: Gelatin, calcium polyphosphate fiber (diameter 10-20 μm) and rosin (size: 355-450μm) were used in the present study.METHODS: Calcium polyphosphate fiber was selected as reinforced materials and gelatin as matrix materials. The calcium polyphosphate/gelatin composite of the scaffold for cartilage tissue engineering were fabricated with a solvent-casting,particulate-leaching method.MAIN OUTCOME MEASURES: The microstructures, properties of physical mechanics and degradation were tested.RESULTS: ①Microcosmic observation: The composites had the 3-D, connectivity network microstructures. ②Physical and mechanical properties of scaffold composite: The experimental value of calcium polyphosphate/gelatin composite of the scaffold was consistent with calculated value. Experimental value of porosity was 60%-80%, meeting the requirement of porosity of tissue engineering scaffold composite. The compress modulus of scaffold would be increased with the crossllnkage increasing; ③The degradable rate of the scaffolds composites deteriorated quickly during 0-2 weeks, and slowly after 2 weeks and reduced with increased crosslinkage; the degradable liquid pH value was maintained between 5 and 7.CONCLUSION: The mechanical property and biodegradable property of calcium polyphosphate/gelatin composite can meet the demand of cartilage tissue engineering. This composite might be one of cartilage scaffold materials for cartilage tissue engineering with potentially broad applicability.

Objective To investigate the distribution,drug resistance of bile pathogenic bacteria,and the risk factors for biliary infection.Methods Clinical and laboratory data of patients hospitalized from January 2008 to October 2015 were reviewed for pathogenic bacteria and drug resistance,and the factors related to biliary tract infection were studied.Results Among all 320 cases,there were 249 cases of pathogenic bacteria in bile specimens,the positive rate was 77.81％.There were 356 strains of pathogenic bacteria of 40 species,including 244 strains of gram negative bacteria (68.54％),93 strains of gram positive bacteria (26.12％) and 19 strains of fungi (5.34％).Top three bacteria were Escherichia coli (84 strains,23.60％),Klebsiella pneumonia (60 strains,16.85％),and Enterococcus faecium (40 strains,11.24％).The Escherichia coli and Klebsiella pneumoniae had the highest drug resistance to cefazolin,and they had a lower drug resistance to cefoxitin and amikacin.The multivariate analysis showed that age ≥ 60 years (AOR =2.311,95％ CI:1.292-4.135) and the history of ERCP operation (AOR =3.475,95％ CI:1.587-7.607) were independent risk factors for biliary tract infection.Conclusion Bacteria are mainly gram negative bacteria in the bile of patients with biliary tract infection,suggesting antibiotics with low resistant rate of gram-negative is the first choice.The age ≥ 60 years and history of ERCP surgery are independent risk factors for patients with biliary tract disease.Measures to prevent biliary infections in high-risk patients should be taken.

Objective To investigate the inhibitory effect of blocking PI3K/AKT pathway by wortmannin on hypoxia-inducible factor 1α (HIF-1α) and the effect on the expression of glycolysis associated genes in human esophageal carcinoma cell lines TE1 and TE13,and to analyze the relation between PI3K/AKT-HIF-1α pathway and glycolysis in esophageal carcinoma cells. Methods Esophageal carcinoma cell lines TE1 and TE13 pretreated with wortmannin (2 μmol/L) were incubated under normoxic and hypoxic conditions.And each cell line was divided into four groups.The expression of HIF-1α and glycolysis associated genes GLUT-1,LDHA and HK-Ⅱ at protein level were measured by.Western blot.The expression of HIF-1α,GLUT-1,LDHA and HK-Ⅱ at mRNA level was determined by real-time PCR. The activities of LDH and HK-Ⅱ and lactic acid (LA)concentration in the culture supernatant were tested with spectrophotometer method.Results Under normoxic condition,HIF-1α was expressed in TE1 cells and the expression of HIF-1α was inhibited by wortmannin (2 μmol/L),the most significant inhibitory effect was at 12 hours,therefore 12 hours was selected for the subsequent hypoxia experiment.Compared with untreated cells,the expression of HIF-1α、HK-Ⅱ 、GLUT-1、LDH-A at protein level significantly decreased in TE1 and TE13 cells after pretreated with wortmannin (P ＜ 0.05),and the expression of HIF-1α、HK-Ⅱ at mRNA level significantly decreased (P＜ 0.05).Under normoxic and hypoxic conditions,the HK-Ⅱ and LDH activities in TE1 and Te13 esophageal carcinoma cells significantly decreased after treated with wortmannin compared with untreated cells (P＜0.05).Under hypoxia condition,the enzyme activity increased in untreated cells (P＜ 0.05). Under normoxic and hyp0xic conditions,the lactic acid concentration in the culture supernatant obviously decreased in cells treated with wortmannin compared with untreated cells (P＜ 0.05). Under hypoxia condition,lactic acid concentration increased in wortmannin treated cells (P ＜ 0.05). Conclusions Under normoxic and hypoxic conditions,wortmannin decrease lactic acid concentration through inhibiting the expression of HIF-1α and glycolysis associated genes, which indicate PI3K/AKT-HIF-1α pathway was closely related to glycolysis in esophageal carcinoma cells.

Objective To investigate the correlation of single nucleotide polymorphisms( SNP) of rs228648 and rs2890565 in urotensin Ⅱ (UTS2)gene with polycystic ovary syndrome(PCOS). Methods The genotypes of two SNPs in UTS2 gene were determined through polymerase chain reaction Tin-shift genotyping method. 101 Chinese Han families trios in Shandong Province consisting of fathers,mothers,and affected daughters with PCOS and 105 healthy women were recruited. The physiological and biochemical parameters including serum follicular stimulating hormone(FSH),luteinizing hormone( LH),testosterone,fasting plasma glucose,and insulin were also measured. Results The distributions of three genotypes and two alleles of SNP rs228648 in UTS2 gene were similar between PCOS group and control group. The distributions of genotypes of SNP rs2890565 in UTS2 gene differed significantly between PCOS group and control group (P<0. 05). The frequency of A allele of SNP rs2890565 in UTS2 gene was significantly higher in PCOS group than that in control group( P<0.05). Transmission disequilibrium test(TDT) did not show significantly biased transmission of two different alleles from parents to affected daughters at rs228648 locus (P>0. 05) ,but showed an excess transmission of A allele from heterozygous parents to affected offspring at rs2890565 locus (P<0. 05). The carriers with GG genotype of SNP rs228648 had significantly higher HOMA-IR compared to those with AA and AG genotypes. The carriers with AA or AG genotype of SNP rs2890565 had significantly higher fasting plasma glucose and fasting insulin compared to those with GG genotypes. HOMA-IR in cases with AA genotype was significantly higher than that with GG genotype. Conclusions There is no association of SNP rs228648 with PCOS, but exists association with insulin resistance. The genetic polymorphism of UTS2 gene rs2890565 may be associated with PCOS,and the higher frequency of A allele is likely to contribute to PCOS.

Drug slow release in osteomyelitis treatment is an important biomedical problem, to prepare the high effect drug sustained-release bead is the sticking point. A sustained-release bead system consisting of gentamicin sulfate in biodegradable poly(dimer acid-tetradecandioic acid) copolymer [P(DA-TA), WDA: WTA= 50: 50] is prepared by melt casting which may be useful in osteomyelitis treatment. The stability at room temperature and the in vitro release profile in distilling water, in 0.9% saline buffer and in 0.1 mol/LpH7.4 PBS at 37 degrees C of the bead are determined, the drug release behavior in vitro follows the first order release kinetics and Peppas release kinetics equation. In vitro bacteriostatic activity studies demonstrated that the beads possessed desired bacteriostatic activity and lasted for 50 days for Staphylococcus aureus and Escherichia coli, which are common bacteria for infections in bone. All the above suggest that the biodegradable sustained-release beads may be a new treatment device for osteomyelitis treatment.
Delayed-Action Preparations ; chemical synthesis ; pharmacology ; Dicarboxylic Acids ; administration & dosage ; chemical synthesis ; Drug Carriers ; Escherichia coli ; drug effects ; Gentamicins ; administration & dosage ; pharmacology ; Humans ; Microbial Sensitivity Tests ; Osteomyelitis ; drug therapy ; Polyanhydrides ; administration & dosage ; chemical synthesis ; Polymers ; administration & dosage ; chemical synthesis ; Staphylococcus aureus ; drug effects