OBJECTIVETo determine the rheological properties of the photo-polymerized composite resin reinforced with retentive filler (RF) and its rheological difference with normal filler (NF) composite resin.

METHODSRheological properties of the composite resins, such as viscosity, shear stress and creep compliance, were measured with dynamic stress rheometer at room temperature (25 degrees C).

RESULTSThe viscosity of the composite resin reinforced with RF is higher than that of NF composite resin (P < 0.01); at the beginning, the viscosity of the former has little change with the rising of shear stress and the latter decreases, then the viscosities of the two composite resins increase with the rising of shear stress as soon as over 203.18 Pa of shear stress; the creep compliance of the composite resin reinforced with RF is significant smaller than that of NF composite resin (P < 0.01).

CONCLUSIONSThe rheological properties of the two composite resins have significant difference, so they have different clinical using properties.

Composite Resins ; chemistry ; Dental Restoration, Permanent ; Viscosity

Through scale-up cultivation of Eriobotrya japonica suspension cells using WAVE bioreactor, the cell growth and ursolic acid (UA) accumulation were studied. The comparison test was carried out in the flask and the reactor with cell dry weight (DW) and UA content as evaluation indexes. The culture medium, DW and UA content were compared in 1 L and 5 L working volumes of bioreactor. The orthogonal test with main actors of inoculation amount, speed and angle of rotation was developed to find the optimal combination, in 1 L working volume of bioreactor. DW of the cell growth and the UA content in bioreactor were higher than those of the shaker by 105.5% and 27.65% respectively. In bioreactor, the dynamic changes of elements in the fluid culture, the dry weight of the cell growth and the UA content in 1 L and 5 L working volumes were similar. Inoculation of 80 g, rotational speed of 26 r · min(-1), and angle of 6 ° was the optimal combination, and the cell biomass of 19.01 g · L(-1) and the UA content of 27.750 mg · g(-1) were achieved after 100 h cultivation in 1 L working volume of bioreactor. WAVE Bioreactor is more suitable than flasks for the E. japonica cell suspension culture, and culture parameters can be achieved from 1 L to 5 L amplification.
Biomass ; Bioreactors ; Cell Culture Techniques ; instrumentation ; methods ; Culture Media ; chemistry ; metabolism ; Eriobotrya ; chemistry ; growth & development ; metabolism ; Triterpenes ; analysis ; metabolism

OBJECTIVESTo investigate the effect of particle size distribution (PSD) of dental poly (methyl methacrylate) (PMMA) beads on the microstructure of denture.

METHODSIt was compared and analyzed that the porosity of three groups of spherical specimens which were made of PMMA beads with different PSD at proper polymer/monomer ratios. And the final microstructure of each group was investigated using Digital High Definition Microscope.

RESULTSWith proper polymer/monomer ratio increasing, the occurrence of porosity tended to decrease. The final microstructure of denture varied with PSD of PMMA beads.

CONCLUSIONBy means of optimizing PSD of beads, the microstructure of denture could be improved, and the occurrence of porosity could be reduced.

Dental Materials ; chemistry ; Dentures ; Particle Size ; Polymethyl Methacrylate ; chemistry

[Objective] To observe the effects of autophagy induced by different doses of ultraviolet B (UVB) irradiation on the apeptosis in human skin fibroblasts.[Methods] Skin fibroblasts were isolated from the circumcision specimen of a 23-year-old healthy male,and subjected to a primary culture.After 3 to 10 passages,the cells were collected and applied in the following experiment.Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferation of some fibroblasts treated with different concentrations (0,0.5,2.0,5.0and 10.0 mmol/L) of 3-methyladenine (3-MA).To qualitatively and quantitatively detect the autophagy in fibroblasts treated with different concentrations of 3-MA and in fibroblasts treated with 3-MA of 0.5 mmol/Lfollowing UVB irradiation,monodansylcadaverine (MDC) staining was carried out,and immunofluorescence was used to detect the expression of microtubule-associated protein 1 light chain (LC3).Some fibroblasts were classified into 8 groups to remain untreated,be irradiated with UVB of 30,50 and 100 mJ/cm2 alone,treated with 3-MA of 0.5 mmol/L alone,or treated with 0.5 mmol/L 3-MA following irradiation with UVB of 30,50 and 100 mJ/cm2,respectively,then,cell apoptosis was qualitatively detected by Hoechst and propidium iodide (PI)staining,and quantitatively detected by flow cytometry with annexin V and PI.[Results] The percentage of autophagic cells was (63.037 ± 5.876) ％ in fibroblasts treated with starvation condition,significantly decreased to (34.425 ± 5.183) ％ in fibroblasts treated with 3-MA of 0.5 mmol/L.The expression of LC3 showed a gradually increasing trend from untreated fibroblasts,to fibroblasts irradiated with UVB of 30,50 and 100 mJ/cm2,while the increase was attenuated by the 4-hour treatment with 3-MA immediately after the irradiation.Compared with the other concentrations,the 3-MA of 0.5 mmol/L showed the least influence on the viability of fibroblasts.The addition of 3-MA of 0.5 mmol/L increased the percentage of cells both positive for Hoechst and PI staining in fibroblasts irradiated with UVB of 50 mJ/cm2,but decreased that in fibroblasts irradiated with UVB of 100 mJ/cm2.Similarly,the percentage of middle and late apoptotic cells was significantly higher in fibroblasts irradiated with UVB of 50 mJ/cm2 followed by treatment with 3-MA of 0.5 mmol/L than in those irradiated with UVB of 50 mJ/cm2alone ((10.933 ± 0.839) ％ vs.(7.267 ± 0.473) ％,t =5.20,P＜ 0.05),but lower in fibroblasts irradiated with UVB of 100 mJ/cm2 followed by treatment with 3-MA of 0.5 mmol/L than in those irradiated with UVB of 100 mJ/cm2alone ( (7.100 ± 0.781 ) ％ vs.( 1 0.133 ± 0.681 ) ％,t =6.29,P ＜ 0.05 ).[Conclusion]s The irradiation with UVB of 50 mJ/cm2 may protect fibroblasts by inducing autophagy and suppressing apoptosis,while the high level of autophagy induced by UVB of 100 mJ/cm2 may lead to autophagic cell death in fibroblasts.

Objective To introduce a new technique for urethral coverage in Snodgrass hypospadias repair,and to evaluate its effectiveness and complications.Methods From April 2003 to February 2006, this new procedure was performed in 289 children with hypospadias aged 3 months to 12 years (mean age,2. 4 years).The native meatus of urethra was identified subcoronal in 78 cases,penile/shaft in 136,penoscrotal in 36 and scrotal in 16;and 23 cases had undergoneⅡstage operation and re-operation.The overlapping coverage with bilateral shaft based vascularized dartos pedicle was done in the new urethra by Snodgrass hy- pospadias repair in these children.Results All the cases were followed for 3 months to 2 years.Postoper- atively,urinary fistulas developed in 32 cases (11%).Of them,11 were cured spontaneously within 4 weeks. The incidence of actual urinary fistula was 7% (21/289).Of the 21 fistulas which were not cured,11 (5%) occurred in 214 cases of distal hypospadias;and 10 (13%) in 75 cases of proximal hypospadias,Ⅱstage and re-operation.No dehiscence and diverticulum was found.Combined with mucosal collar technique,the ventral skin of the penis was sewn on the midline.During the follow-up,excellent cosmetic results with normal-ap- pearing circumcised penis were achieved in most patients.Conclusions Bilateral shaft based vascularized dartos pedicle urethral coverage procedure is a reliable and effective method for preventing urethral cutaneous fistulas and dehiscence.This method can reconstruct a satisfactory cosmetic appearance of the penis.

OBJECTIVETo study the monomolecular coverage of the silane coupling agent gamma-methacryloxypropyltrimethoxysilane (gamma-MPS) on the barium glass filler surface.

METHODSKubelka-Munk (K-M) function values of the isolated OH-groups on the barium glass filler surface, which were based on the change of gamma-MPS concentrations, were measured using the quantitative analysis of the diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. When all of the isolated OH-groups on the filler surface disappeared (where the K-M function values was zero), the monomolecular coverage of the gamma-MPS molecules on the filler surface was indicated by the linear regression analysis.

RESULTSThe relationship tallied with negative linear correlation between the K-M function values of the isolated OH-groups on the barium glass surface and the concentrations of gamma-MPS. Each gamma-MPS molecule occupied 0.21 nm(2) when the monomolecular coverage was formed on the barium glass surface.

CONCLUSIONSThe result of this study indicated the optimal amount of silane coupling agent on silanated barium glass filler during the production of resin composite.

Barium Compounds ; chemistry ; Composite Resins ; chemistry ; Dental Materials ; chemistry ; Methacrylates ; chemistry ; Silanes ; chemistry ; Silicon Dioxide ; chemistry

To study the expression of angiotensin converting enzyme 2 (ACE2) and angiotensin (Ang) 1-7 specific receptor Mas protain in renal blood vessels of metabolic syndrome ( MS) rats and its anti-oxidative effect. A total of 80 male SD rats were divided into four groups: the normal control group (NC, the same volume of normal saline), the MS group (high fat diet), the MS + Astragali Radix group (MS + HQ, 6 g x kg(-1) x d(-1) in gavage) and the MS + Valsartan group (MS + XST, 30 mg x kg(-1) x d(-1) in gavage). After four weeks of intervention, their general indexes, biochemical indexes and blood pressure were measured; plasma and renal tissue Ang II, malondialdehyde (MDA) and superoxide demutase (SOD) levels were measured with radioimmunoassay. The protein expressions of Mas receptor, AT1R, ACE and ACE2 were detected by western blot analysis. According to the result, compared with the NC group, the MS group and the MS + HQ group showed significant increases in systolic and diastolic pressures, body weight, fasting glucose, fasting insulin, triglycerides, free fatty acid and Ang II level of MS rats (P < 0.05). The MS + XST group showed notable decreases in systolic and diastolic pressures than that of the MS group. The MS group showed significant increases in the SOD activity and NO level and decrease in the MDA level after being intervened with Astragali Radix. ACE and AT1R protein expressions in renal tissues of the MS group were higher than that in the NC group, but with lower ACE2 and -Mas receptor expressions (all P < 0.05). Compared with the MS group, the MS + HQ group showed significant increase in Mas receptor expression in renal tissues, whereas the MS + XST group showed notable decrease in AT1R (all P < 0.05). In conclusion, Astragali Radix can increase the Mas receptor expressions in renal tissues, decrease ACE expression and change local Ang II, MDA, NO and SOD in kidneys, so as to protect early damages in renal tissues.
Angiotensin I ; metabolism ; Animals ; Astragalus Plant ; chemistry ; Blood Glucose ; metabolism ; Blood Pressure ; drug effects ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Kidney ; drug effects ; injuries ; metabolism ; Male ; Malondialdehyde ; metabolism ; Metabolic Syndrome ; drug therapy ; genetics ; metabolism ; physiopathology ; Peptide Fragments ; metabolism ; Peptidyl-Dipeptidase A ; genetics ; metabolism ; Proto-Oncogene Proteins ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley ; Receptors, G-Protein-Coupled ; genetics ; metabolism ; Signal Transduction ; drug effects

BACKGROUNDPatients with pelvic fractures are often treated in hospitals without the capacity to implement an open reduction internal fixation (ORIF). This often leads to pelvic malunion in patients with unstable pelvic fracture, shock or even death due to uncontrollable pelvic hemorrhage and unstable hemodynamics. This study explored the role of early external fixation (within 7 days) for patients with unstable pelvic fractures.

METHODSA retrospective analysis was conducted on 32 patients with unstable pelvic fractures treated with early external fixation from January 2005 to January 2010 (Tile type B: 18 cases; C: 14 cases). The study comprised 28 males and 4 females, with a mean age of (32 ± 8) years (range, 21-56 years). Of these patients, 22 were treated with emergency pelvic external fixation and 10 were treated with external fixation within 1-7 days. Fifteen cases suffered traumatic hemorrhagic shock. A statistical analysis was conducted to compare fluid infusion and blood transfusion volumes within the first 24 hours of these shock patients with another cohort of patients treated without early external fixation from January 1993 to January 1998.

RESULTSThe average follow-up was (34.7 ± 14.6) months (range, 6-66 months). Six to eight weeks after external fixation, patients could walk with crutches; by 12 weeks, external fixation was removed and all fractures had healed. Seven patients presented with sequelae, including 3 patients with long-term lumbosacral pain, 3 patients with erectile dysfunction and 1 patient with Morel-Lavallee lesion and other complications. The 15 shock patients in this study (2005-2010 group) required significantly lower volumes of fluid infusion and blood transfusion (P(fluid) = 0.000; P(transfusion) = 0.000) as compared to the 1993-1998 cohort.

CONCLUSIONSThe early application of external fixation in unstable pelvic fracture patients positively affects hemodynamic stability, with outstanding efficacy as a final fixation option for unstable pelvic fractures.

Adult ; External Fixators ; Female ; Fracture Fixation ; methods ; Fractures, Bone ; physiopathology ; surgery ; Hemodynamics ; Humans ; Male ; Middle Aged ; Pelvic Bones ; injuries ; Retrospective Studies

The aim of this study was to investigate the support effects of mesenchymal stem cells (MSCs) on umbilical cord blood (UCB) CD34+ cell (HSPC) expansion in vitro and its influence on cell characteristics including the surface marker of CD34+ cells, homing adhesion molecules and colony-forming ability. The mononucleated cells (MNCs) were isolated from UCB, then the CD34+ cells were isolated from freshly obtained MNCs by immunomagnetic beads, the MSC feeder cells exposed to gamma-ray of 137Cs were prepared by MSC feeder. The CD34+ cells were inoculated in different culture media. Experiment was divided into 3 groups: HSPC+CK group in which cytokines were added to medium (SCF, FL and TPO); HSPC+MSC group in which CD34+ cells were inoculated on MSC feeder; HSPC+MSC+CK group in which cytokines and MSC feeder cells were added to medium. After culture for 4, 7, 10, 14 days the MNC amount was counted and expansion ability of CD34+ cells was evaluated. The immunotypes of CD34+ cells and subsets, homing adhesion molecules and colony-forming ability in different groups detected by flow cytometry. The results showed that the amount of MNCs and CD34+ cells all obviously increased during culture for 14 days, the expansion levels of MNCs in 3 groups were HSPC+MSC+CK group>HSPC+CK group>HSPC+MSC group in proper order. Within 10 days of expansion in vitro amount of MNCs obtained significant expansion, meantime the expansion of CD34+ cells was higher also. The CD34+ count in 3 groups at day 4 of culture decreased significantly as compared with 0 day of culture (p<0.01). The CD34+ cells ratios in 3 groups after expansion were HSPC+MSC group>HSPC+MSC+CK group>HSPC+CK group in proper order (p<0.01), while CD34+ subset levels in 3 groups were different, the CD34+CD38- cells in HSPC+CK group at 4 days of culture increased transiently (62.71%), then quickly decreased, the CD34+CD38- cell ratio at day 7 was 0.05%, while the CD34+CD38- cell ratio in HSPC+MSC group at day 7 was 18.92%, difference was significant as compared with HSPC+CK group (p<0.05). The analysis of colony-forming units showed that the colony-forming ability at various time points after expansion all sustained in high level. It is concluded that in short-time (<7 day) culture of UCB CD34+ cells the combination of MSCs with cytokines can significantly expand the CD34+ cells and make the HSPCs to maintain original biologic characteristics.
Antigens, CD34 ; Cell Culture Techniques ; Cell Proliferation ; Cells, Cultured ; Culture Media, Serum-Free ; Fetal Blood ; cytology ; immunology ; Flow Cytometry ; Humans ; Immunophenotyping ; Mesenchymal Stromal Cells ; cytology ; immunology

OBJECTIVETo evaluate the association between metabolism of arsenic and DNA oxidative damage in workers in a arsenic mill.

METHODSUrinary organic arsenic and 8-hydroxydeoxyguanine were detected in 37 workers highly exposed to arsenic and 16 administrative and logistic staff with mild exposure in a arsenic mill in Yunnan province, and also 28 local people who did not have the exposure in the near past time. The correlation between metabolism of arsenic and DNA oxidative damage was evaluated.

RESULTSThe urinary organic arsenic concentration was respectively (0.48 +/- 0.37) mg/L and (0.08 +/- 0.05) mg/L for men with high and low exposure, and was respectively 0.11 mg/L and (0.30 +/- 0.24) mg/ L for women with high and low exposure, while it was lower than 0.02 mg/L in the controls. Urinary 8-hydroxydeoxyguanine concentration was (18.07 +/- 11.68) micromol/mol creatinine, (11.79 +/- 8.25) micromol/mol creatinine, (10.07 +/- 3.04) micromol/mol creatinine for the males with high and low exposure and of controls, respectively, (P < 0.05), and it was 84.35 micromol/mol creatinine, (21.27 +/- 5.89) micromol/mol creatinine, (14.43 +/- 2.58) micromol/mol creatinine for females with high and low exposure and of controls, respectively. The female workers exposed to arsenic had higher urinary 8-hydroxydeoxyguanine levels than males did (P < 0.05). The increased tendencies of urinary 8-hydroxydeoxyguanine levels with the organic arsenic concentration were found in workers (r(s) = 0.279, P = 0.019).

CONCLUSIONOccupational individuals exposed to arsenic have obvious DNA oxidative damage, which is more severe in females. The difference of metabolism of arsenic may play a key role.

Adult ; Arsenicals ; urine ; China ; Female ; Guanine ; analogs & derivatives ; urine ; Humans ; Male ; Middle Aged ; Occupational Exposure ; analysis