OBJECTIVETo evaluate the dentin and enamel bonding strength and resin-dentin interfaces of four resin cements.

METHODSTwenty-four sound freshly extracted molars were sectioned with low-speed saw under running water. Two mesial-distal enamel disc and two buccal-lingual dentin discs were sectioned from each molar. Four resin cements (A group: Panavia(TM) F; B group: RelyX(TM) ARC; C group: RelyX(TM) Unicem; D group: Clearfil(TM) SA Cement) were applied to the surface of these enamel and dentin discs according to manufacturers' guidance. The bonded specimen were prepared for shear bond strength test and sectioned occluso-gingivally into two slabs for scanning electron microscopy (SEM) observation.

RESULTSThe bonding strength between resin and enamel in B group [(29.38 ± 6.28) MPa] was higher than that in D group [(27.25 ± 7.03) MPa], and both of them were significantly higher than those in A [(22.92 ± 7.13) MPa] and C group [(10.92 ± 3.41) MPa] (P < 0.05). The highest dentin bonding strength was shown in B group [(27.28 ± 6.79) MPa], followed by A [(14.23 ± 6.39) MPa], D [(10.09 ± 3.26) MPa] and C group [(6.43 ± 1.60) MPa, P < 0.05].

CONCLUSIONSThe four resin cements have different enamel or dentin bonding properties.

Bisphenol A-Glycidyl Methacrylate ; chemistry ; Dental Bonding ; Dental Enamel ; ultrastructure ; Dental Stress Analysis ; Dentin ; ultrastructure ; Dentin-Bonding Agents ; chemistry ; Humans ; Microscopy, Electrochemical, Scanning ; Molar ; Polyethylene Glycols ; chemistry ; Polymethacrylic Acids ; chemistry ; Resin Cements ; chemistry ; Shear Strength

BACKGROUNDAt least five mismatch repair (MMR) genes, including hMSH2, hMLH1, hPMS, hPMS2, and hMSH6/GTBP, are associated with hereditary nonpolyposis colorectal cancer (HNPCC). More than 90% of families with HNPCC harbor the hMSH2 and hMLH1 gene mutations. We have analyzed the clinical features of HNPCC among Chinese patients and report the results of screening for mutations in the hMSH2 and hMLH1 genes.

METHODSThe data concerning gender, site of colorectal cancer (CRC), age at diagnosis, history of synchronous and/or metachronous colorectal cancer, instance of extracolonic cancers, and histopathology of tumors for 126 patients from 28 independent families with HNPCC were collected. Fifteen of the families met the Amsterdam I criteria, and 13 met the Japanese clinical criteria for diagnosis. Genomic DNA was extracted from the peripheral lymphocytes. Polymerase chain reaction (PCR) and denaturing high-performance liquid chromatography (DHPLC) were used to screen the coding region of the hMSH2 and hMLH1 genes. Samples showing abnormal DHPLC profiles were sequenced.

RESULTSOne hundred and seventy malignant neoplasms were found in the 126 patients, of whom 23 had multiple cancers. Ninety-eight of the patients (77.8%) had colorectal cancers, with an average age at onset of 45.9 years and a right-sided predominance. Eight hMSH2 or hMLH1 gene sequence variations were found in 12 families, and a germ-line G204X nonsense mutation in the third exon of hMSH2 was found, representing the first mutation in an MMR gene ever found in people of Chinese Mongolian ethnicity.

CONCLUSIONSHNPCC is a typical autosomally dominant hereditary disease, characterized by early onset, a predominance of proximal colorectal cancer, and multiple synchronous and metachronous colorectal cancers. DHPLC is a powerful tool for detecting mutations in the hMSH2 and hMLH1 genes. Mutations in the first nine exons of the hMLH1 gene were more common in Chinese patients.

Adaptor Proteins, Signal Transducing ; genetics ; Adult ; Aged ; Asian Continental Ancestry Group ; genetics ; China ; Colorectal Neoplasms, Hereditary Nonpolyposis ; ethnology ; genetics ; DNA Mutational Analysis ; Female ; Germ-Line Mutation ; Humans ; Male ; Middle Aged ; Models, Genetic ; MutL Protein Homolog 1 ; MutS Homolog 2 Protein ; genetics ; Nuclear Proteins ; genetics ; Pedigree ; Polymerase Chain Reaction

OBJECTIVETo investigate the potential effect of proanthocyanidins (PA), a natural cross-linker, on the stability of resin-dentin bonds against thermal cycling.

METHODSTen percent, 15% PA-based preconditioners, and 5% glutaraldehyde were prepared for the transient pretreatment of demineralized dentin before bonding. Specimens without pretreatment were used as negative controls (n = 4 teeth for each group). Microtensile bond strength, failure mode, micromorphologies of resin-dentin interface and the collagen degradation of bonded specimens after thermal cycling were evaluated.

RESULTSAfter thermal cycling, the microtensile bond strength values of resin-dentin bond in groups pretreated with 15% PA for 120 s and 60 s [(23.09 ± 3.19) and (21.88 ± 3.49) MPa] were significantly higher than that in control group [(15.47 ± 3.78) MPa] (P < 0.05). Mixed fractures were the most prevalent failure mode. Specimens with pretreatment presented compact hybrid layer, while some narrow gaps were found in hybrid layer of non-treated specimens. Collagen biodegradation rates in groups with pretreatment were significantly lower than that in control group (P < 0.05). Among them, specimens pretreated by 15% PA preconditioner for 120 s exhibited the lowest biodegradation rates [(0.316 ± 0.019) mg/g].

CONCLUSIONSThe application of natural cross-linker PA on demineralized dentin reduced the bond degradation against aging by thermal cycling, and can be helpful to create more durable bonds to dentin.

Collagen ; metabolism ; Dental Bonding ; Dental Stress Analysis ; Dentin ; Dentin-Bonding Agents ; Humans ; Proanthocyanidins ; pharmacology ; Resin Cements ; Temperature ; Tensile Strength ; drug effects

OBJECTIVESTo observe the influence of wen-yang herbs on the hemodynamics in liver fibrotic rats.

METHODSWistar rats with liver fibrosis, induced by carbon tetrachloride and alcohol, were randomly divided into a treatment group and a control group. The treatment group was administered wen-yang herbs and the control group saline. At the end of the experiment, the hemodynamic markers of the liver and the mesentery, the liver function and hydroxyproline content of liver tissues between the two groups were compared. Blood volume of the livers and hydroxyproline content of liver tissues were also determined.

RESULTSBlood volume of the liver and mesentery (P < 0.01) and blood flow velocity of small vein of mesentery (P < 0.05) of the treatment group were distinctly higher than the control group. The hydroxyproline content (P < 0.01) of the treatment group was remarkably reduced and liver function was improved.

CONCLUSIONWen-yang herbs can activate microcirculation of the liver and mesentery, decrease the deposit of collagen in the liver and improve liver function.

Animals ; Blood Circulation ; drug effects ; Drugs, Chinese Herbal ; therapeutic use ; Liver Cirrhosis, Experimental ; drug therapy ; physiopathology ; Male ; Phytotherapy ; Random Allocation ; Rats ; Rats, Wistar

OBJECTIVETo probe the feasibility and efficacy of damage control orthopedics (DCO) in treating severe multiple injuries.

METHODSA retrospective analysis was made on the clinical data of 41 patients (31 males and 10 females, aged 18-71 years, mean: 36.4) with multiple injuries admitted to our department and treated by DCO from January 1995 to December 2005.

RESULTSAs a first-stage therapy, devascularization of internal iliac arteries was performed in 29 patients with pelvic fractures combined with massive bleeding, including ligation of bilateral internal iliac arteries in 21 patients and embolization of bilateral internal iliac arteries in 8. And early external fixation of pelvis was performed in 10 patients. Ten patients with severe multiple injuries combined with femoral fractures were managed with primary debridement and temporal external fixation and 2 patients with spinal fractures combined with spinal cord compression received simple laminectomy. Thirty-one patients received definite internal fixation after resuscitation in intensive care unit. The overall mortality rate was 12.1% (5/41) with an average injury severity score of 41.4. The main causes of death were hemorrhagic shock and associated injuries. Complications occurred in 7 patients including acute respiratory distress syndrome in 3 cases, thrombosis of right common iliac artery in 1, subphernic abscess in 2 and infection of deep wound in lower extremity in 1. After treatment, all the patients got cured.

CONCLUSIONSPrompt diagnosis and integrated treatment are keys to higher survival rate in patients with severe multiple injuries. In this condition, DCO is an effective and safe option.

Adolescent ; Adult ; Aged ; Critical Care ; methods ; Female ; Humans ; Male ; Middle Aged ; Multiple Trauma ; mortality ; surgery ; Orthopedic Procedures ; methods ; Retrospective Studies

OBJECTIVETo measure the spectral transmittance of Cerinate porcelain veneer and enamel in different color and different thickness.

METHODSSamples of Cerinate porcelain veneers were prepared in different thickness (0.50 mm, 0.75 mm, 1.00 mm) and different Vita shade (A1, A2, A3). Enamel samples in shade A2 were made with three thickness (0.50 mm, 0.75 mm, 1.00 mm). A spectrophotometer with spectra range (380-800 nm) was employed to measure the spectral transmittance.

RESULTSSpectral transmittance decreased with the increasing in the thickness of specimens and decreasing in the color darkness. The transmittance of Cerinate porcelain veneer material and enamel in the same color and same thickness hadn't significant difference.

CONCLUSIONThe key factor to spectral transmittance of porcelain veneer materials is veneer's thickness, and the color of the materials has also some influence on it. Cerinate porcelain veneers can properly recover the transparency of teeth.

Ceramics ; Color ; Dental Enamel ; Dental Porcelain ; Dental Veneers ; Humans ; Spectrophotometry

OBJECTIVEThe purpose of this study was to evaluate the clinical result of 546 tetracycline-stained teeth corrected with Cerinate porcelain laminate veneer system for esthetic purpose.

METHODS546 tetracycline-stained teeth were corrected with Cerinate porcelain veneer system, and bonded with Ultra Bond resin cement. The restorations were recalled after 0.5 year, 1.5 years and 2.5 years, respectively. modified Ryge criteria were used to evaluate the veneers marginal adaptation, interfacial staining, secondary caries, postoperative sensitivity and the patients' satisfaction with the shade of the restorations.

RESULTSthis study found that 99% veneers had excellent marginal adaptations; and less than 1% veneers were rebonded after debond in the first half year application; the color of the veneers was stable and no evident staining was found. Almost all patients were satisfied with their restoration color after 1 year's application.

CONCLUSIONThe research indicated that Cerinate porcelain veneer restoration system is a reliable and ideal choice for the correction of tetracycline-stained teeth.

Anti-Bacterial Agents ; adverse effects ; Color ; Composite Resins ; Dental Marginal Adaptation ; Dental Porcelain ; Dental Veneers ; Humans ; Tetracycline ; adverse effects ; Tooth Discoloration ; chemically induced ; therapy ; Treatment Outcome

OBJECTIVETo evaluate the nanoleakage appearance in 6 dentin adhesives.

METHODSSuperficial occlusal dentin of 12 human molars without caries extracted freshly was exposed with 600-grit SiC papers under running water. Six adhesives were applied to dentin surfaces according to the manufacturers' instructions. The bonded teeth were sectioned occluso-gingivally into 0.9-mm-thick serial slabs that were stored in ammoniacal silver nitrate solution in the dark for 24 h and prepared for transmission electron microscope. The extent of nanoleakage among 6 dentin adhesives was measured and compared using one-way ANOVA.

RESULTSThe nanoleakage was observed obviously at the dentin-resin interfaces of all 6 adhesives. The average dentin nanoleakage values of Group A [BangDuo, (16.09 +/- 2.08)%], Group B [Single Bond, (13.39 +/- 1.81)%], and Group C [Prime&Bond NT, (11.27 +/- 1.94)%] were all significantly different (P < 0.05). There was no significant difference in the dentin nanoleakage between Group D [B(1), (12.13 +/- 2.11)%] and Group E [Clearfil SE Bond, (12.35 +/- 2.60)%], but both of them were lower than Group F [Adper Prompt, (14.93 +/- 2.67)%].

CONCLUSIONSThe nanoleakage phenomena at the dentin-resin interface were all observed diversely in the contemporary dental adhesives.

Dental Leakage ; Dentin ; ultrastructure ; Dentin-Bonding Agents ; classification ; Humans ; In Vitro Techniques ; Materials Testing ; Microscopy, Electron, Transmission ; Molar

Huperzine A is a potent,reversible,and blood-brain barrier permeable acetylcholinesterase irhibitor.The aim of this study was to compare the pharmacokinetics,tolerability,and bioavailability of two formulations with the established reference formulation of huperzine A in a fasting,healthy Chinese male population.This was a randomized,single-dose,3-period,6-sequence crossover study.The plasma concentrations of huperzine A were determined by liquid chromatography tandem mass spectrometry.Tolerability was assessed based on subject interview,vital sign monitoring,physical examination,and routine blood and urine tests.The mean (SD) pharmacokinetic parameters of the reference drug were Cmax,1.550 (0.528) ng/mL;t1/2,12.092 (1.898) h;AUC0-72h,17.550 (3.794) ng.h/mL.Those of the test formulation A and test formulation B were Cmax,1.412 (0.467),1.521 (0.608) ng/mL;t1/2,12.073 (2.068),12.271 (1.678) h;AUC0-72h,15.286 (3.434) ng.h/mL,15.673 (3.586) ng.h/mL.The 90％ confidence intervals for the AUC0-72h and Cmax were between 0.80 and 1.25.No adverse events were reported by the subjects or found with results of clinical laboratory test.The test and reference products met the regulatory criteria for bioequivalence in these fasting,healthy Chinese male volunteers.All three formulations appeared to be well tolerated.

Objective To explore the long-term effect of endemic arsenism on oxidative stress and immune function, and to provide scientific basis for prevention and treatment of the disease in the areas. Methods In 2009, Using cluster sampling and typical investigation, the cross-sectional study was completed. The patient groups and the internal control group were selected in the arsenism areas after 5 years quality improvement of drinking water(Silizhuang village, Daying village and Gucheng village in Shanyin county, Gucheng city, Shanxi province) and they were divided into mild, moderate, severe case and internal control groups, respectively. The external control group was selected in a non-arsenism area(Yangzhuang village in Heshengbu city). The Oxidative stress indicators were determined and analyzed [serum superoxide dismutase (SOD) activity was determined with xanthine oxidase method, glutathione peroxidase(GSH-Px) activity was determined with 2-thio-2-nitrobenzoic acid method, and mmuuity malondisldohyde(MDA) levels was determined with thiobarbituric acid method]. The immune function was determined and analyzed [immunoglobulin G (IgG) was determined with radioimmunoassay method, and serum lysozyme was determined with turbidimetric method]. Results A total of 252 people were surveyed, in which the external control group, the internal control group, mild, moderate and severe patient groups were 56, 57, 49,44 and 46, respectively. Serum SOD activities were (72.19 ± 11.75), (66.96 ± 12.02), (49.79±11.07), (48.54 ±10.56) and (47.68 ± 10.68)kU/L, respectively. The difference of serum SOD activities between the groups was statistically significant(F = 52.42, P ＜ 0.01 ). Serum SOD activities in the external control group were significantly higher than other groups (all P ＜ 0.05). The value in the internal control group was significantly higher than the 3patient groups (all P ＜ 0.05). There were no significant differences between the case groups (P ＞ 0.05). Serum GSH-Px activities of the five groups were (197.41 ± 38.54), (195.02 ± 31.93), (187.26 ± 28.22), (187.24 ± 25.40),(186.88 ± 21.84)U/mg, respectively, and the difference between the groups was not significant(H = 4.21, P ＞0.05). Serum MDA levels of the five groups were (4.51 ± 2.14), (5.88 ± 2.00), (6.44 ± 2.83), (5.89 ± 2.57),(5.88 ± 2.40)μ mol/L, respectively, and the difference between the groups was statistically significant(F = 3.36,P ＜ 0.05). The external control group was significantly lower than other groups(all P ＜ 0.05). No significant difference was observed between other groups(all P ＞ 0.05). Serum IgG levels were(11.16 ± 2.08), (8.15 ± 1.44), (8.77 ±2.54), (9.19 ± 1.97), (8.44 ± 2.52)g/L, respectively, and the difference between the groups was statistically significant(H = 52.92, P ＜ 0.01 ). The external control group was significantly higher than other groups(all P ＜0.05). No significant difference was observed between other groups(all P ＞ 0.05). Serum lysozyme levels were (13.57 ± 5.16), (10.05 ± 3.96), (8.78 ± 3.35), (8.72 ± 3.76), (9.38 ± 4.26)mg/L, respectively, and the difference between the groups was statistically significant (H = 35.00, P ＜ 0.01 ). The external control group was significantly higher than other groups(all P ＜ 0.05). No significant difference was observed between other groups(all P ＞ 0.05). Conclusions The effect of arsenic on the body's oxidative stress response and immune function persists after 5 years of drinking low arsenic water. In addition to intensify arsenic removal from drinking water, it should also strengthen the monitoring of population's health in the diseased areas.