In-vitro performance and fracture strength of thin monolithic zirconia crowns

PURPOSE: All-ceramic restorations required extensive tooth preparation. The purpose of this in vitro study was to investigate a minimally invasive preparation and thickness of monolithic zirconia crowns, which would provide sufficient mechanical endurance and strength. MATERIALS AND METHODS: Crowns with thickness of 0.2 mm (group 0.2, n=32) or of 0.5 mm (group 0.5, n=32) were milled from zirconia and fixed with resin-based adhesives (groups 0.2A, 0.5A) or zinc phosphate cements (groups 0.2C, 0.5C). Half of the samples in each subgroup (n=8) underwent thermal cycling and mechanical loading (TCML)(TC: 5℃ and 55℃, 2×3,000 cycles, 2 min/cycle; ML: 50 N, 1.2×106 cycles), while the other samples were stored in water (37℃/24 h). Survival rates were compared (Kaplan-Maier). The specimens surviving TCML were loaded to fracture and the maximal fracture force was determined (ANOVA; Bonferroni; α=.05). The fracture mode was analyzed. RESULTS: In both 0.5 groups, all crowns survived TCML, and the comparison of fracture strength among crowns with and without TCML showed no significant difference (P=.628). Four crowns in group 0.2A and all of the crowns in group 0.2C failed during TCML. The fracture strength after 24 hours of the cemented 0.2 mm-thick crowns was significantly lower than that of adhesive bonded crowns. All cemented crowns provided fracture in the crown, while about 80% of the adhesively bonded crowns fractured through crown and die. CONCLUSION: 0.5 mm thick monolithic crowns possessed sufficient strength to endure physiologic performance, regardless of the type of cementation. Fracture strength of the 0.2 mm cemented crowns was too low for clinical application.

The modified antegrade digital artery island flap for severely flexion contracture of the burned finger / 中华显微外科杂志

Objective To investigate the clinical outcomes of using modified antegrade digital artery island flap for the treatment of the severely flexion contracture of the burned finger.Methods Between August,2013 to August,2015,21 patients (21 fingers) with severely flexion contracture of the burned finger were hospitalized for treatment.According to the Stren classification standard for the interphalangeal joint flexion contracture,all the patients were rated as type Ⅲ.The volar soft-tissue defect with exposed tendons,nerves,vessels or bone ranged from 1.0 cm × 2.0 cm to 2.5 cm × 4.0 cm after scar relaxation.The artery and the nerve defect were 1.5 to 4.5 cm and 2.0 to 4.2 cm,respectively.The wound were reconstructed with the modified antegrade digital artery island flap.The dorsal branches of the proper digital nerve of the flap were anastomosised with the proper digital nerve of the wound.The flap donor site was resurfaced with full-thickness skin grafting from inner aspect of the forearm.All the cases were called back for postoperative follow-up.Results All the reconstructed fingers and flaps survived completely without vascular problems.The donor skin graft survived and wound healed by first intention.All the patients were followed up with 11.5 months (range,6-22 months).The finger appearance was satisfactory.The texture and color of flaps in all cases were good.There was no pigmentation and contraction relapse.The contracted fingers received no cold intolerance.At the final examination,the average values of static 2-point discrimination were 5.2 mm (range,4.3-6.5 mm) of the flap.In the series,based on the Michigan Hand Outcome Questionnaire,18 patients were strongly satisfied with the injured finger appearance and 3 patients satisfied with the appearance.Conclusion The modified antegrade digital artery island flap,which is easy to raise with large flap size and can result with the good finger appearance and function,is an ideal technique for reconstruction of the severe flexion contracture of the burned finger.

ERp44 C160S/C212S mutants regulate IP3R1 channel activity

Previous studies have indicated that ERp44 inhibits inositol 1,4,5-trisphosphate (IP(3))-induced Ca(2+) release (IICR) via IP(3)R(1), but the mechanism remains largely unexplored. Using extracellular ATP to induce intracellular calcium transient as an IICR model, Ca(2+) image, pull down assay, and Western blotting experiments were carried out in the present study. We found that extracellular ATP induced calcium transient via IP(3)Rs (IICR) and the IICR were markedly decreased in ERp44 overexpressed Hela cells. The inhibitory effect of C160S/C212S but not C29S/T396A/ΔT(331-377) mutants of ERp44 on IICR were significantly decreased compared with ERp44. However, the binding capacity of ERp44 to L3V domain of IP(3)R(1) (1L3V) was enhanced by ERp44 C160S/C212S mutation. Taken together, these results suggest that the mutants of ERp44, C160/C212, can more tightly bind to IP(3)R(1) but exhibit a weak inhibition of IP(3)R(1) channel activity in Hela cells.

Pharmacodynamics of different local anestheties administered intrathecally for elderly patients undergoing transurethral resection of the prostate / 中华麻醉学杂志

Objective To investigate the pharmacodynamics of different local anesthetics administered intrathecally for elderly patients undergoing transurethral resection of the prostate (TURP). Methods Ninety ASA Ⅰ - Ⅲ elderly patients, aged 69-82 yr, with body mass index less than 30 kg/m2 , undergoing TURP under combined spinal-epidural anesthesia, were randomly divided into 3 groups ( n = 30 each): levobupivacaine group (group L), ropivacaine group (group R) and bupivacaine group (group B). Group L, R and B received intrathecai (IT) 0.5 % levobupivacaine, 0.5 % ropivacaine and 0.5 % bupivacaine respectively. The initial dose was 7,10 and 6 mg in group L, R and B respectively. The ratio of two successive doses was 0.9. If the upper sensory block reached T10 within the 20 min after IT injection, the IT analgesia was considered to be effective. The median effective dose (EDs0) and 95 % confidence interval (95 % CI) were calculated by Dixon. Results The ED50 and 95% CI of levobupivacaine, ropivacaine and bupivacaine were 6.781 (95% CI 6.561-7.024) mg, 9.135 (95%CI8.670-9.616) mg and 5.170 (95% CI 5.012-5.333) ng respectively. The relative potency ratio between levobupivacaine, ropivacaine and bupivacaine is 0.76∶0.57∶1.00. ConclusionThe relative potency ratio be tween levobupivacaine, ropivacaine and bupivacaine is 0.76∶0.57∶1.00.

Clinical study on ambulatory labor analgesia used in latent phase of the first stage of labor / 中国医师进修杂志

Objective To evaluate the clinical effect of ambulatory labor analgesia used in latent phase of the first stage of labor, which include labor progress, Apgar score after ambulatory labor analgesia begun to use when the cervix was different size dilatated. Methods Seventy-five parturient primiparas who had no complication were randomly divided into three groups: group Ⅰ: ambulatory labor analgesia was begun to use when the cervix was 1.0 cm dilated, group Ⅱ: ambulatory labor analgesia was begun to use when the cervix was 2-3 cm dilated, group Ⅲ: control group without use of ambulatory labor analgesia. Analgesic effects were observed, changes of uterine contraction were recorded by fetal monitor. Meanwhile, total stage of labor ,outcome of delivery and Apgar score were recorded. Results Duration of total stage of labor had no significant difference between group Ⅰ and group Ⅲ.The duration of the first labor stage was significantly longer in group Ⅰ than that in group Ⅱ(P

Effect of ultra-fine powder of Bletilla striata on experimental gastric ulcer in rats / 中草药

Objective To compare the pharmacodynamics of common Bletilla striata powder(80 and 200 meshes) with ultra-fine powder of B.striata on experimental gastric ulcer in rats and to clarify how much the dose of B.striata was decreased after superfine comminution.Methods The models of gastric ulcer were set up by anhydrous alcohol and acetic acid to measure the gastric ulcer area and count out the inhibitory rate;The tissue slice of gastric ulcer cicatrix was got far HE staining.Based on the viewpoint of pathology the morbid state was observed.Results B.striata powder could decrease the gastric ulcer area significantly,and the groups of ultra-fine powder were advantaged to the others.Conclusion After superfine comminution,the potency of B.striata can be improved with its dose reducing.It is good for mo-dernization of making dosage forms.

Pharmacokinetics of 5-ISMN Orally Disintegrating Tablets in Healthy Volunteers / 中国药房

OBJECTIVE:To develop an HPLC method for the determination of 5-ISMNconcerntrations in human plasma and study the pharmacokinetics of 5-ISMN orally disintegrating tablets and the reference tablets.METHODS:A single oral dose test capsule(orally disintegrating tablets)or reference capsule of 5-ISMN(60 mg)were administered by randomized crossover way in 20 healthy male volunteers with plasma 5-ISMN concentrations determined by HPLC.The pharmacokinetic parameters were calculated with 3p87 pharmacokinetic program and the bioavailability of the two preparations was evaluated.RESULTS:The main pharmacokinetic parameters of the test preparation vs.the reference preparation were as follows:Cmax:(613.42?73.83)vs.(368.64?38.66)?g?mL-1;tmax:(26.52?2.00)vs.(95.73?4.16)min;AUC0～∞:(73 872.24?543.89)vs.(77 978.47?646.37)ng?min?mL-1,respectively.CONCLUSION:The assay was proved to be sensitive,accurate and suitable for pharmacokinetic study of 5-ISMN.The results of pharmacokinetic study after oral administration of test and reference preparations of 5-ISMN showed that the two preparations were bioequivalent while the test preparation had a higher peak concentration and could reach peak level in less time,and the test preparation showed a rapid drug releasing behavior.