16 standered acrylic resin blocks with silicone resilient denture liner(10 mm ×8 mm ×3 mm)incorporated with nano-silver par-ticles at 5% (m/m,by dry wet)in-between were prepared.8 blocks were immersed in distilled water for 24 h at 37 ℃ as the controls (group 1).Another 8 were thermocycled for 4 000 cycles(group 2).16 acrylic resin bars were thermal cycled for 4 000 cycles.Then they were processed exactly as the control group (group 3).Tensile bond strength of the specimens was measured by a universal testing machine. The bond strength values(MPa)of group 1,2 and 3 were 2.683 ±0.435,2.179 ±0.633 and 1.460 ±0.566 respectively(group 1 vs 2,P>0.05;group 3 vs 1 or 2,P<0.05).The failure mode of the blocks in group 1 and 2 was mainly cohesive failure,in group 3 adhesion fail-ure.

To understand the pyrolysis mechanism of lignin with α-O-4 linkage, 4-(3-hydroxy-1-phenoxypropyl)-phenol was selected as an α-O-4 type lignin dimer model compound, and its pyrolysis process was studied by density functional theory with M06-2X method at 6-31+G (d,p) level. Equilibrium geometries of the reactant, intermediates, transition states and products were fully optimized. The activation energies in each pyrolysis pathway were calculated. The dimer decomposed mainly through the homolytic cleavage and concerted decomposition of the C(α)-O linkage. Pyrolytic products mainly included various phenolic compounds such as phenol, 4-methylphenol, 4-vinylphenol and p-coumaryl alcohol, as well as light compounds such as ethanol, methanol and formaldehyde. Pyrolytic depolymerization process has its potential in biomass-based fuels.
Biofuels ; Biomass ; Cresols ; chemistry ; Ethanol ; chemistry ; Formaldehyde ; chemistry ; Hot Temperature ; Lignin ; chemistry ; Methanol ; chemistry ; Phenols ; chemistry ; Propionates ; chemistry

Objective:To evaluate the effect of thermocycling on nano-silver-incorporated silicone denture liner for Candida albicans (CA)adhesion.Methods:Specimens(1 0 mm ×1 0 mm ×3 mm)of silicone denture liner(control)and that incorporated with nano-sil-ver were prepared according to the manufacturer's direction.8 of the each kind of specimens were immersed in distilled water for 24 h at 37 ℃,and 8 were subjected to thermocycling for 4 000 cycles at temperatures ranging from (5 ±1 )℃to (55 ±1 )℃with a 60 s dwell time per temperature.In vitro CA adhesion assay was used to measure the levels of adherence to the specimens.Data were analysed sta-tistically.Results:Thermocycling increased CA adhesion to control specimens(P<0.05),and did no change the adhesion to nano-sil-ver incorporated specimens(P>0.05 ).The adhesion of CA to nano-silver incorporated specimens was fewer than that to the controls with or wihout themocycling(P<0.01 ).Conclusion:Nano-silver incorporation may inhibit CA adhesion to silicone denture liner.Ther-mal cycling has no influence on C.albicans adhesion to silicone denture liner incorporated nano-sliver.

Objective To observe the repairing effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) and goserelin on chemotherapy-induced ovarian injury, and the distribution and growth of hUC-MSCs transplanted in rat chemotherapy-induced ovarian injury. Methods A total of 120 SD rats were randomized into group A-E:A normal group, B NS control group, C goserelin group, D hUC-MSCs group and E hUC-MSCs+goserelin group. The rat premature ovarian failure (POF) model was established by given a loading dose of cyclophosphamide (CTX, 50 mg/kg) followed by daily intraperitoneal injection of CTX (8 mg/kg) for consecutive 14-day. The hUC-MSCs were injected through caudal vein, and goserelin was given by subcutaneous injection 4 days before POF model established. The serum level of estrogen was detected and numbers of follicles were counted. After GFP was transfected by lentivirus, the distribution and growth of stem cells transplanted in rats were observed by animal in vivo imaging system. Results At day 46, the serum level of estrogen showed no significant difference between group A and group E (P > 0.05). There were no significant differences in the counted follicles between group A and group E (P>0.05). After tail vein injection of the transfected cells, GFP positive cells were found in injury ovarian. Conclusion There is a repairing effect of hUC-MSCs and goserelin on ovarian injury.

Objective To investigate correlation between the results of drug susceptibility and the extent of drug-resistances in Mycobacterium tuberculosis clinical isolates. Methods Liquid culture and MTT test were used. Twelve anti-TB drug MICs and drug susceptibility testing of the 163 MTB strains from random clinical isolates were detected, which including RFP, INH, SM, EBM, OFLX, LVFX, MOX, AMK,CPM, PTA, CLA and PAIN. Results There are 67% (42/62) Mycobacterium tuberculosis strains resistant to SM, 63% (51/81) Mycobacterium tuberculosis strains resistant to INH, 77% (50/65) Mycobacterium tuberculosis strains resistant to RFP, 41% ( 15/37 ) Mycobacterium tuberculosis strains resistant to AMK,41% (12/29) Mycobacterium tuberculosis strains resistant to CPM, 20% (12/60) Mycobacterium tuberculosis strains resistant to EMB and 43% (25/58) Mycobacterium tuberculosis strains resistant to OFLX which MICs were equal to or more than 16 μg/ml, 8 μg/ml, 8 μg/ml, 16 μg/ml and 4 μg/ml, 4 μg/ml and 8 μg/ml,respectively. There were significant differences in the MICs of OFLX, LVFX and MOX in OFLX resistant strains (2-128, 1-32 and 0.0625-1 μg/ml, respectively) by ANOVA ( F = 16.874, P ＜ 0.001 ). The MICs of SM, INH, RFP, EMB, OFLX, AMK and CPM in isolates resistant to six or seven drugs (0.5-128,2-64,0.25-128,1-32,1-64,0.5-128 and 1-128 μg/ml,respectively) were higher than those (0.25-128,0.0625-64,0.25-32,0.25-2,0.125-2,0.5-4 and 1-4 μg/ml,respectively) in isolates resistant to one or two drugs (F=20.066, 40.499, 47. 197, 70.373, 91.432, 41.840 and 21.547, respectively, P ＜0.05). The MICs of SM, INH, RFP and EMB in isolates resistant to four drugs (1-128,2-64,0.25-128 and 1-32 μg/ml,respectively ) were higher than those ( 0.25-128,0.0625-64, 0.25-64 and 0.25-2 μg/ml,respectively) in isolates resistant to one or two drugs (F = 26.242, 23.563, 31.541 and 64.469,respectively, P ＜0.05).The MICs of RFP in MDR isolates (2-64 μg/ml) were higher than those (0. 25 μg/ml) in other resistant isolate except M DR isolates (F = 5.613, P <0.05). Conclusions The study shows that there are associations between the results of routine drug susceptibility testing and the resistant extent of anti-TB drugs. This could help doctors select more effective anti-TB regimen for TB patients according to the correlations.

Objective Fecal biomarkers have emerged as an important tool for assessing and monitoring disease activity in patients with inflammatory bowel disease ( IBD) .We aimed to investigate the diagnostic value of fecal neopterin and calprotectin in pa-tients with active inflammatory bowel disease and made comparison with that of serum C-reactive protein ( CRP) . Methods A total of 151 consecutive patients with IBD (84 CD and 67 UC) provided 2 gram fecal samples for the measurement of fecal neopterin( FNP) and calprotectin( FCP) concentrations and 2 milliliter blood samples for the serum C-reactive protein measurement before undergoing a colonoscopy.ELISA was applied in the measurement.Clinical disease activities were scored independently according to the Best Crohn′s Disease Activity Index(CDAI) in patients with CD, while the Modi-fied Mayo Scores in patients with UC.Comaprison was made in the relativity of each fecal marker and IBD activity score, the optimum value of diagnosing IBD acitivity as to each fecal marker, as well as sensitivity, specificity, moreover, receiver operating characteristic curve ( ROC) was drawn.50 healthy volunteers who received a normal colonoscopy were also enrolled as the control group and asked to give a 2 gram fresh stool sample. Results The FNP and FCP concentrations in patients with IBD were significantly higher than those in healthy control group(P<0.05).Both FNP and FCP concentrations differed significantly in clinically active IBD when compared with those in patients with inactive disease( P<0.001) .In CD patients, the correlation coefficients of FNP and FCP with CDAI were 0.55 and 0.59, respectively(P<0.001).In UC patients, the correlation coefficients of FNP and FCP with Mayo scores were 0.74 and 0.77, respectively( P<0.001) .The correlation coefficients of serum CRP in CD and UC patients with clinical scores were 0.49 and 0.60, respectively(P<0.001).The area under the ROC curve(AUC) of FNP and FCP for the diagnosis of clinical activity in pa-tients with CD were 0.75 and 0.80, respectively.The AUC of FNP and FCP in UC patients were 0.85 and 0.90, respectively.The AUC of serum CRP in patients with CD and UC were 0.65 and 0.74, respectively.When combined FNP with FCP, the AUC in pa-tients with CD and UC were 0.85 and 0.92, respectively. Conclusion FNP is a novel reliable and non-invasive biomarker to evalu-ate clinical disease activity in patients with IBD as accurate as FCP, It is advisable to combine FNP with FCP to evaluate disease activi-ty in patients with IBD.

Objective To explore the feasibility of extending liver blood perfusion cessation by ultrasound combining microbubbles.Methods The livers of 9 healthy rabbits were treated with a pulsed therapeutic ultrasound device,in presence of microbubbles.For quantification of liver perfusion,contrastenhanced ultrasonography was performed on 6 rabbits before treatment and at different time points of 0 min,30 min,60 min and 48 hours after treatment.Pathological examination of the treated livers was performed immediately after treatment on the other 3 rabbits.Results The liver blood perfusion almost vanished immediately after treatment,remained at a low perfusion level from 30 to 60 min,and completely recovered 48 hours later.The peak intensity dropped from ( - 51.88 ± 4.26)dB to ( - 62.53 ± 4.83)dB after treatment and rose up to ( - 52.00 ± 4.60) dB 48 hours later.The peak intensities before treatment and 48 hours after treatment were significantly higher than those of 0 min,30 min and 60 min time points after treatment( P ＜0.05).Pathological examination showed significant swelling of hepatocytes and hemorrhage around portal veins.Conclusions Microbubbles enhanced ultrasound can induce liver blood perfusion cessation for up to 1 hours.The mechanism could be swelling of hepatocytes and hemorrhage of portal track.

The blood-brain barrier in humans significantly restricts the effective delivery of drugs into the brain, resulting in poor therapeutic efficacy and difficulty in brain disease management. In recent years, innovative strategies and novel preparations have been studied and developed in order to circumvent the blood-brain barrier, achieve efficient drug entry into the brain, minimize the incidence of peripheral adverse effects, and bring significant therapeutic outcomes to patients. This review summarizes some key development strategies for treating encephalopathy, to provide some insights for the development of the next generation of drugs.

pUDK-HGF, the recombinant plasmid DNA encoding human hepatocyte growth factor (HGF), can treat ischaemic disease. A great quantity of pharmaceutical pUDK-HGF is needed. A pilot-scale production process of pUDK-HGF was established based on a new chromatographic media (plasmidselect), including fermentation, cell harvesting, alkaline lysis, ultrafiltration, RNA removing and buffer exchanging on Sephacryl S-1000, capturing supercoiled plasmid DNA with plasmidselect, and removing the salt with Sepharose 6BFF. The process does not use RNase enzyme and toxic solvents.
DNA, Recombinant ; biosynthesis ; DNA, Superhelical ; isolation & purification ; Escherichia coli ; genetics ; metabolism ; Fermentation ; Genetic Vectors ; genetics ; Hepatocyte Growth Factor ; biosynthesis ; genetics ; Humans ; Pilot Projects ; Plasmids ; isolation & purification

Objective: To study the relationship between XRCC1 gene polymorphism and DNA damage in peripheral blood lymphocytes of workers exposed to coal tar pitch. Methods: 203 coal tar asphalt device operation area workers (exposure group) and 76 logistics management personnel (control group) as the research ob-ject, determination of 1-hydroxypyrene concentrations in the urine as polycyclic aromatic hydrocarbons expo-sure dose, using the alkaline comet assay evaluation a peripheral blood lymphocyte DNA damage degree, using TaqMan MGB real time PCR method to detect XRCC1 gene 3 loci (XRCC1-194, XRCC1-280 and XRCC1-399) single nucleotide polymorphism. Results: No significant differences was observed in age, sex, smoking and alco-hol consumption between the two groups (P>0.05). The level of 1-OHP in the exposed group was significantly higher than that in the control group (1.27±0.93 μg/g creatinine) (P<0.05). The comet Olive tail moment level (3.21±0.93) in the peripheral blood lymphocytes of the exposed group was significantly higher than that in the control group (0.94 ± 0.39) (P<0.05). There was no significant difference in genotype distribution of XRCC1-194, XRCC1-280 and XRCC1-399 between the two groups (P>0.05). There was a significant correlation be-tween the XRCC1-280 locus gene polymorphism and comet Olive tail moment in the exposure group (P<0.05) af-ter adjustment for sex, age, smoking rate, drinking rate, length of service and urinary 1-OHP concentration. The comet Olive tail moment level of GG individuals carrying wild homozygous genotype was significantly lower than that of individuals carrying heterozygous genotype GA and carrying mutant homozygous genotype AA (P< 0.05) , and the difference was statistically significant (P<0.05) The comet Olive tail moment level of heterozy-gous genotype GA was significantly lower than that of genotype AA with mutational homozygous genotype AA (P<0.05) , and the difference was statistically significant (P<0.05). Conclusion Arg280His locus polymor-phism of XRCC1 gene may influence the DNA damage level of peripheral blood lymphocytes induced by occupational exposure to coal tar pitch.