OBJECTIVETo explore a simple but novel method of strengthening gypsum material by cyanoacrylate infiltration. To evaluate the influence of cyanoacrylate on the mechanical properties of dental gypsum models.

METHODSGypsum specimens were polished to the dimension of 35 mmx4 mmx4 mm. Butyl-cyanoacrylate was diluted with chloroform at different concentrations, namely 20% and 30% cyanoacrylate. Gypsum specimens were infiltrated by diluting one component of cyanoacrylate at different concentrations for 8 h and then dried for analysis. The changes in elastic modulus, fracture toughness, compressive strength, biaxial strength, brinell hardness were measured. The data were analyzed using software OriginPro 8.

RESULTSThe viscosity measurements indicated that diluted cyanoacrylate were Newtonian fluids and the viscosity increased slightly within the 48 hours of preparation but still similar as water at room temperature, which could be used to infiltrating gypsum. The gypsum infiltrated with cyanoacrylate exhibited good physicochemical properties. The biaxial strength, fracture toughness, compressive strength and brinell hardness of the gypsum were improved by 39%, 30%, 63% and 18%, respectively.

CONCLUSIONCyanoacrylate can significantly improve the strength of gypsum model which indicates the potential clinical application.

Calcium Sulfate ; Cyanoacrylates ; Dental Models ; Hardness

The aim of this paper is to report the synthesis of the mPEG-PCL-g-PEI copolymers as small interfering RNA (siRNA) delivery vector, and exploration of the siRNA delivery potential of mPEG-PCL-g-PEI in vitro. The diblock copolymers mPEG-PCL-OH was prepared through the ring-opening polymerization. Then, the hydroxyl terminal (-OH) of mPEG-PCL-OH was chemically converted into the carboxy (-COOH) and N-hydroxysuccinimide (NHS) in turn to prepare mPEG-PCL-NHS. The branched PEI was reacted with mPEG-PCL-NHS to synthesize the ternary copolymers mPEG-PCL-g-PEI. The structure of mPEG-PCL-g-PEI copolymers was characterized with Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR) and gel permeation chromatography (GPC). The mPEG-PCL-g-PEI/siRNA nanoparticles were prepared by complex coacervation, and the nanoparticles size and zeta potential were determined, separately. The cytotoxicities of mPEG-PCL-g-PEI/siRNA nanoparticles and PEI/siRNA nanoparticles were compared through cells MTT assays in vitro. The inhibition efficiencies of firefly luciferase gene expression by mPEG-PCL-g-PEI/ siRNA nanoparticle at various N/P ratios were investigated through cell transfection in vitro. The experimental results suggested that the ternary (mPEG5k-PCL(1.2k))1.4-g-PEI(10k) copolymers were successfully synthesized. (mPEG(5k)-PCL(1.2k))1.4-g-PEI(10k) could condense siRNA into nanoparticles (50-200 nm) with positive zeta potential. MTT assay results showed that the cytotoxicity of (mPEG(5k)-PCL(1.2k))1.4-g-PEI(10k)/siRNA nanoparticles was significantly lower than that of PEI(10k)/siRNA nanoparticles (P < 0.05). The expression of firefly luciferase gene could be significantly down-regulated at a range of N/P ratio from 50 to 150 (P < 0.01), and maximally inhibited at the N/P ratio of 125. The mPEG-PCL-g-PEI polymers could delivery siRNA into cells to inhibit the expression of target gene with very low cytotoxicity, which suggested that mPEG-PCL-g-PEI could serve as a new type of siRNA delivery vector.

Objective To isolate and cultivate mouse hepatic progenitor cells (mHPCs) from E14.5 mouse fetal liver in vitro and induce mHPCs differentiation into cholangiocytes.Methods Isolation of mHPCs from mouse fetal liver was based on the cell surface antigen delta-like protein 1/preadipocyte factor 1 (Dlk/Pref-1) by a fluorescence-activated cell sorter (FACS).Then mHPCs isolated were co-cultured with/without mouse embryonic fibroblasts (MEFs) by using Transwell.The cell antigen alpha-fetoprotein (AFP), albumin (ALB) and cytokeratin19 (CK19) expression in freshly isolated DLK1+cells or co-cultured for 4 days and 6 days were observed with immunocytochemical method.Results When co-cultured with MEFs, the division and proliferation were observed in most of DLK1+ cells and grape-like aggregation was formed.Cells began to adhere to growth and began to become spindle-shaped on 4th day.The DLK1+cells isolated freshly by FACS were expressed AFP and low levels of ALB but not expressed CK19.But, these cells expressed CK 19 and weak expression of ALB on 4th day.In addition, the expression of CK19 increased and the expression of ALB almost not detected on 6th day.Conclusions Most of DLK1+ cells, isolated from E14.5 fetal livers by FACS, are proved to be mHPCs.Furthermore, these cells can proliferate quickly and differentiate into cholangiocytes by co-culture with MEFs.

[Objective]To evaluate the role of mature cumulus cells from oocyte-cumulus complex(OCC)in in-vitro maturation(IVM)and establish a new culture technique which is convenient to carry out.[Methods]The cumulus cells of OCC were cut off and dispersed by 1 mL syringe.The cumulus cells were co-cultured with the immature oocytes retrieved from the COH cycles after they adherent to the bottom of the dish.The immature oocytes were experienced IVM procedures in different culture media.They were divided into 3 groups(the oocytes at germinal vesicle stage from one woman were allotted to the same group randomly).Group 1(solution A):basic culture medium+human follicular fluid(hFF);Group 2(solution B):solution A+ cumulus cells(OCC);Group 3(solution C):solution A+ OCC+ follicle stimulating hormone(FSH)+ epidermal growth factor (EGF).Then,the maturation rate,fertilization rate and formation rate of available embryo were observed.[Results]In 113 treatment cycles,298 immature oocytes were performed IVM with solution A,B,and C.The difference for 24 hour maturation rates among 3 groups wag statistically significant(A:45.2%,B:61.7%,C:78.2%,P＜0.05).There was no statistical difference for 25～48 hour maturation rates and normal fertilization rates of mature oocytes.The differences of cleavage rates and rescued embryo rates between group 1 and 2,group 1 and 3 were statistically significant(P＜0.05).The formation rates of available embryo showed an increasing trend from group 1,2,to 3.[Conclusion]After being dispersed by simply beat upon with syringe and adherent culture,the mature cumulus eells from mature OCCs in COH cycles,together with growth factors in the follicular fluid or extraneously supplemented,could promote the IVM of immature oocyte.

Objective To determine the risk factors for emergence agitation (EA) during the recovery period after general anesthesia.Methods One thousand and thirty-four patients of both sexes aged 18-89 yr undergoing general anesthesia were divided into EA group and non-EA group.EA occurring during recovery from general anesthesia was assessed by using Riker sedation-agitation scale.Age,sex,complication,education,medical history,ASA physical status,type and duration of anesthesia and operation,volume of blood loss,fluid replacement,urine volume,duration of stay in PACU,number of drainage tubes and so forth were recorded.Multivariate logistic regression was used to analyze the risk factors for the occurrence of EA.Results Thirty-six patients developed EA during recovery from anesthesia.The incidence of EA was 3.5 ％.Logistic regression indicated that high risk operation,premedication with diazepam,induction of anesthesia without midazolom and fluid replacement during operation were the risk factors for EA (P ＜ 0.05).Conclusion High-risk operation,premedication with diazepam,induction of anesthesia without midazolom and fluid replacement during operation are the risk factors for EA during recovery from general anesthesia.

Objective To investigate the relationship between the tube voltage and radiation dose as well as image quality in adult upper airway digital radiography (DR).Methods We used CDRAD2.0 contrast details phantom and PMMA to simulate adult upper airway. With different tube voltages,the phantom was exposed using automatic exposure control system (AEC).The entrance surface dose( ESD),dose area product(DAP) and mAs in every exposures were recorded.The image quality factors(IQF) of all images were calculated. Results With tube voltage increasing,ESD,DAP,mAs decreased and IQF value enhanced.There were statistically significance ( F =45.15,26.41,29.26,56.53,P ＜ 0.05 ).ESD,DAP,mAs significantly increased with tube voltage less than 75 kV,began to decrease when tube voltage more than 75 kV,tended to be on the balance in 75 -80 kV.At the same time,the fluctuation of IQF value was no statistical difference in 50 - 75 kV of tube voltage,but was statistical significance in 75 -90 kV( F =11.35,P ＜0.05 ).So,the image quality of adult upper airway with different tube voltage had no significant difference.Conclusions The appropriate tube voltage was 75 kV to 80 kV in the upper airway DR.The IQF value can be provided as the clinical evaluation index of image quality.

Objective To investigate the correlations of extracellular matrix and hepatic ultramicrostructural changes with clinical manifestations in patients with mild chronic hepatitis B (CHB).Methods Patients with chronic HBV infections were enrolled and were divided into mild CHB group (n=66) and HBV carrier group (n=10).Serum samples were collected from patients, and serum HBV markers, HBV DNA load and liver fibrosis indexes were measured.All subjects received liver biopsy, and the tissue samples were observed by light microscope and electron microscope.T test and χ2 test were performed for measurement data and enumeration data, respectively.Spearman test was used for ranked data.Results The differences on ALT and AST levels between mild CHB group and HBV carrier group were significant (t=12.42, 7.06, P＜0.05), but there was no significant difference on HBV DNA load between two groups (t=0.24, P ＞ 0.05).Serum liver fibrosis indexes (hyaluronic acid, type Ⅲ collagen,type Ⅳ collagen and laminin protein) in mild CHB group were not significantly higher than those in HBV carrier group (t=0.45, 0.95, 0.76 and 1.21, P ＞0.05).In mild CHB group, there were 33 patients with ≥G2 and ≥S2, but in HBV carrier group were only 2 patients (χ2=4.17, P ＜ 0.05).Seventeen patients in mild CHB group were with S3-4, while that was not observed in HBV carrier group (χ2=4.75, P ＜0.05).In mild CHB group, hepatic ultramicrostrutural changes on fat storing cell, collagen protein and portal area were correlated with fibrosis grades, and the correlation coefficients were 0.351, 0.675 and 0.301, respectively (P=0.004, 0.000 and 0.014).Conclusion Electron microscope is of higher sensitivity than light microscope in observing hepatic ultramicrostructural changes, which is effective in evaluating the severity of mild CHB.

Objective To study the effect of electroacupuncture on the behavior of APP/PS1 transgenic mice of different age, and to explore the optimal intervention time of electroacupuncture in treating Alzheimer's disease (AD). Method APP/PS1 double-transgenic mice of 4 months, 6 months and 9 months old, 20 in each age group, were randomized into a model group and an electroacupuncture group, and ten C57BL/6 wild-type mice were taken as a control group; after 6-week electroacupuncture treatment, the Morris water maze was adopted for spatial memory and behavioral test, and the changes of behavior in each group were observed.Result Of the 5-month-old mice, there were no significant between-group differences (P>0.05), while the time factor (day) produced a statistical significance (P<0.01); of the 7-month-old mice, there were significant differences considering the different groups, time factor and interaction (P<0.01); of the 10-month-old mice, there were significant differences considering the different groups, time factor and interaction (P<0.05). The spatial probe test showed that there were significant between-group differences in comparing the platform crossings and swimming distance in platform quadrant in each age group (P<0.05).Conclusion Electroacupuncture can improve the learning and memory of APP/PS1 double-transgenic mice, the age of 6-7 months old is possibly the optimal intervention time of electroacupuncture for AD, but there still requires further mechanism studies.

OBJECTIVETo explore the mechanism of pricking blood therapy (PBT) for allergic rhinitis (AR).

METHODSThe model rat of experimental allergic rhinitis (EAR) was established by administration of ovoglohulin and they were divided into five groups randomly: a model group, a PBT group, a TCM point application group, a beclomethasone dipropionate (BDP) treatment group, and a health control group. Adrenocorticotrophic hormone (ACTH) contents in hypothalamus, pituitary gland, adrenal gland and plasma were determined by radioimmunoassay before and after treatment.

RESULTSThe ACTH levels in the hypothalamus, pituitary gland, adrenal gland and plasma in the rat of EAR were lower than those in the health control group (P < 0.01). After treatment of pricking blood ther, ACTH levels in the above tissues increased significantly (P < 0.01), with very significant differences (P < 0.01) as compared with the model group, similar to those in the BDP group (P > 0.05).

CONCLUSIONPricking blood therapy has a regulatory action on ACTH in HPA axis of rats with experimental allergic rhinitis.

Adrenocorticotropic Hormone ; Animals ; Hypothalamo-Hypophyseal System ; Hypothalamus ; Pituitary-Adrenal System ; Rats ; Rhinitis, Allergic

BACKGROUNDRenal transplantation in sensitized candidates remains a highly significant challenge worldwide. The production of panel reactive antibody (PRA) against human leukocyte antigen (HLA) is a major risk factor in presensitized recipients. The aim of this study was to evaluate the impact of HLA matching and recipients' PRA on two-year outcome in presensitized renal allograft recipients.

METHODSWe determined the percentage of panel reactivity and specificity of anti-HLA immunoglobulin (Ig) G antibodies in 73 presensitized renal allograft recipients compared with 81 unsensitized recipients (control group). HLA genotyping of both recipients and corresponding donors was performed by PCR with sequence-specific primers (PCR-SSP). We analyzed the factors influencing the early graft outcome (two-year rejection rates and survival rates of the grafts), including HLA mismatching, class and degree of panel reactivity, and target antigen of donors.

RESULTSPresensitized recipients had a worse two-year outcome than unsensitized recipients (P = 0.019 for rejection rate, P = 0.01 for survival rate). The difference in number of HLA-mismatched alleles with either 6-antigen matching (Ag M) standard or amino acid residue matching (Res M) standard was not significant between the rejection and non-rejection groups of presensitized recipients or between the graft survival group and graft loss group. Compared with the control group, recipients with both PRA-I and PRA-II antibodies had a significantly worse two-year outcome (P = 0.001 for rejection rate, P = 0.002 for survival rate). The two-year outcomes of the peak PRA >/= 50% group and its subgroup, at-transplant PRA > or = 50% group, were significantly worse compared with the control group (P = 0.025 and P = 0.001 for rejection rate, P = 0.043 and P = 0.024 for survival rate). The rejection rates of the at-transplant target antigen positive group and its subgroup, HLA-I target antigen positive group, were significantly higher than the control group (P = 0.001 and P = 0.001), target antigen negative group (P = 0.003 and P = 0.001), and peak target antigen positive with negative at-transplant target antigen group (P = 0.024 and P = 0.002). Two-year graft survival rates of the target antigen positive group and HLA-I target antigen positive group were significantly lower than the control group (P = 0.012 and P = 0.001). The two-year outcome of target antigen unknown group was similar to that of the target antigen positive group. Presensitized recipients with pre-transplant plasmapheresis or immunoadsorption (PRA prepared group) had a better but non-significant two-year outcome than the control group. However, the PRA unprepared presensitized recipients were different to the control group (P = 0.004 for rejection rate and P = 0.005 for survival rate). Hyperacute rejection (HR) occurred in three recipients with positive HLA-I target antigen and without mismatch according to Res M and in one case with positive PRA-II (for an unknown target antigen). No HR occurred in eight cases with positive HLA-II target antigens.

CONCLUSIONSPre-transplant PRA preparations might improve the access of presensitized patients to renal donors. Avoiding antigen-positive donors remains a fundamental measure in preventing HR and early rejections.

Adult ; Enzyme-Linked Immunosorbent Assay ; Female ; Graft Rejection ; immunology ; Graft Survival ; immunology ; HLA Antigens ; immunology ; Histocompatibility Testing ; Humans ; Isoantibodies ; blood ; Kidney Transplantation ; adverse effects ; immunology ; mortality ; Male ; Middle Aged ; Transplantation, Homologous ; immunology ; Treatment Outcome