1.Three-dimensional finite element analysis of different abutment angles and loads of the maxillary central incisor
Xiaoxuan CHEN ; Guoqiang LIU ; Xin XU
Chinese Journal of Tissue Engineering Research 2015;(38):6200-6204
BACKGROUND:To optimize the oral implant design in the abutment angle has an important effect on bone resorption, and meanwhile, the high bite force from patients is also crucial to rebuild bone absorption.
OBJECTIVE:To optimize the model design of the maxilary anterior teeth using Ansys Workbench 13.0 software and to investigate the stress size on the cortical and cancelous bone from different angled abutments and different loads of the central incisor.
METHODS:A three-dimensional finite element model of the V-shaped cylindrical threaded implants in the maxilary bone. Abutment angle was set as 0°, 5°, 10°, 15°, 20°, 25°, 30°, and the load stress was set as 90, 105, 120, 135, 150, 165, 180, 195, 210 N. Occlusion of the central incisor was simulated on the implants, and then, buccolingual mechanical loads were loaded on the center of prostheses to observe the effects of different abutment angles and loads on the Von Mises peak stress of the maxila and mandible.
RESULTS AND CONCLUSION:Under the influence of a single factor, when the abutment angles acted as variables, the Von Mises peak stress of the cortical and cancelous bone was respectively increased by 60.60% and 69.30% under labial or palatal loads; when the loading stress acted as variables, the Von Mises peak stress of the cortical and cancelous bone was increased by 68.74% and 69.30% under buccolingual loads. When the loading stress was less than 150 N and the abutment angle was less than 25°, the slop of tangent for the mandible Von Mises stress response curve was-1 to 0. It seems from the mechanical analysis that the stress of cancelous bone is more susceptible to abutment angle and load stress; the optimal abutment of screwed implant should be designed to an angle less than 25° and an bite force less than 150 N.
2.Study on the feasibility of syphilis examination in the blood screening
Lixin YANG ; Jinfeng ZENG ; Xiaoxuan XU
International Journal of Laboratory Medicine 2006;0(02):-
Objective To evaluate the best experimental technique with high-sensitivity and specificity for enhancing positive rate of syphilis screen test and preventing the blood dissemination of this disease.Methods Comparison of the results of TP-ELISA,TRUST and TPPA methods of syphilis examination was performed.Results Using three methods to exam 43,323 samples,299 samples were for positive syphilis.Among them, 294 positive samples with the ELISA method,the positive rate of syphilis test was 98.33%(294/299):92 positive samples with TRUST method,the positive rate only 30.77%(92/299);239 positive samples with TPPA method,the positive rate 79.93%(239/299).Conclusion TP-ELISA method with high sensitivity is suitable for the instrument standardization and data preservation,which is an ideal method for blood screen test of syphilis.For guarantee of blood safety and conventience and economic benefit of blood syphilis screen test, it is the best way to use both TP-ELISA and TRUST methods.The specificity of TPPA method is perfect, which is suitable for confirmation test of syphilis positive samples.
3.Simultaneous Determination of Quercetin and Kaempferol inKaempferia Galanga L. by HPLC
Chuanhua FENG ; Gang LI ; Jing ZHANG ; Lan XU ; Xiaoxuan TAO
Chinese Journal of Information on Traditional Chinese Medicine 2016;23(6):77-79
Objective To establish an HPLC method for the simultaneous determination of quercetin and kaempferol inKaempferia galanga L..Methods ODS2 C18 (5μm, 4.6 mm×150 mm) was used as chromatographic column; methanol-0.4% phosphate (47:53) was the mobile phase; the flow rate was 1 mL/min; column temperature was 30℃; the detection wavelength was 367 nm; the injection volume was 10μL.Results Quercetin showed good linear relationship in the range of 0.016 5–1.65μg (r=0.999 7). The average recovery rate was 96.8%, RSD=2.02%; kaempferol showed good linear relationship in the range of 0.014 6–1.46μg (r=0.999 5). The average recovery rate was 97.3%, RSD=1.77%.Conclusion The method is simple, accurate, and with good reproducibility, which can be used for content determination of quercetin and kaempferol inKaempferia galanga L..
4.Content Determination of Kaempferol in Kaempferia galanga by HPLC
Gang LI ; Chuanhua FENG ; Jing ZHANG ; Lan XU ; Xiaoxuan TAO
China Pharmacy 2016;27(18):2558-2559
OBJECTIVE:To establish a method for the content determination of kaempferol in Kaempferia galanga. METH-ODS:HPLC was performed on the column of Diamonsil ODS2 C18 with mobile phase of methanol-0.4% Phosphoric acid solution at a flow rate of 1 ml/min,detection wavelength was 367 nm,column temperature was 30℃,and injection volume was 10 μl. RE-SULTS:The linear range of kaempferol was 0.001 58-0.158 mg/ml;RSDs of precision,stability and reproducibility tests were low-er than 3%;recovery was 95.52%-99.32%(RSD=1.47%,n=6). CONCLUSIONS:The method is simple,accurate and reproduc-ible,and can be used for the content determination of kaempferol in K. galanga.
5.Quality Standard for Psoraleae Fructus Tinctures
Lan XU ; Xiaoxuan TAO ; Danhui WANG ; Gang LI
China Pharmacist 2015;(2):329-331
Objective:To establish a quality control standard for psoraleae fructus tinctures. Methods:The identification was de-tected by TLC on silica gel G plates with hexane-ethyl acetate (8∶2) as the developing solvent. An HPLC method was applied in the quantitative determination of psoralen and isopsoralen as the effective components. The analytical column was Intersil ODS-3 (250 mm × 4. 6 mm,5 μm) with methanol-water(45∶55) as the mobile phase;the flow rate was 1 ml·min-1;the detection wavelength was at 246 nm and the column temperature was set at 35℃. Results:The characteristic spots for psoralen and isopsoralen were identified by TLC. The concentration of psoralen showed good linearity within the range of 4. 88-187. 50μg·ml-1(r=0. 999 9)and the average re-covery was 102. 63% and RSD was 0. 43%. The concentration of isopsoralen showed good linearity within the range of 4. 25-163. 20μg ·ml-1(r=0. 999 9), and the average recovery was 102. 37% and RSD was 1. 13%. Conclusion: The qualitative and quantitative methods are simple, accurate, feasible and repeatable, which can be used in the quality control of psoraleae fructus tinctures.
6.Determination of Coenzyme A in Coenzyme Complex for Injection by HPLC
Lan XU ; Xiaoxuan TAO ; Chuanhua FENG ; Lang ZHANG ; Gang LI
China Pharmacist 2016;19(2):390-391,392
Objective: To establish an HPLC method for the determination of coenzyme A in coenzyme complex for injection. Methods:The content determination was performed on an Intersil ODS-3 column with methanol-pH 6. 5 phosphate buffer solution (10∶90) as the mobile phase. The detection wavelength was 259 nm and the flow rate was 1. 0 ml·min-1 . The column temperature was 30℃ and the injection volume was 20 μl. Results:The linear range of coenzyme A was 1.624-32.482 u·ml-1(r=0.999 9). The average recovery was 102. 36% and RSD was 1. 14%(n=6). Conclusion: The method is simple, accurate and reproducible, and it can be used for the quality control of coenzyme complex for injection.
7.Effects of sirolimus on scopolamine-induced cognitive dysfunction in rats
Chun YANG ; Tao HONG ; Dongan SU ; Yimin HU ; Xiaoxuan BU ; Jiang SHEN ; Jianguo XU
Chinese Journal of Anesthesiology 2013;(4):427-429
Objective To evaluate the effects of sirolimus on scopolamine-induced cognitive dysfunction in rats.Methods Thirty male Wistar rats,aged 3 months,weighing 200-250 g,were equally randomized into 3 groups:normal saline group (NS group),scopolamine group (SC group) and scopolamine + sirolimus group (SS group).Normal saline,scopolamine 0.8 mg/kg and sirolimus 3.5 mg/kg + scopolamine 0.8 mg/kg were injected intraperitoneally in groups NS,SC and SS,respectively,and the injection was continued for 14 consecutive days.The cognitive function was assessed by Morris water maze test on 15th day.After behavior test,the rats were sacrificed and the prefrontal cortex and hippocampus were harvested for determination of amyloid β protein (Aβ) and Tau protein expression.Results Compared with NS group,the escape latency was significantly prolonged,the ratio of time spent in the target quadrant was decreased,Aβ expression in prefrontal cortex and hippocampus was upregulated and Tau protein expression in prefrontal cortex and hippocampus was down-regulated in group SC (P <0.05 or 0.01).Compared with SC group,the escape latency was significantly shortened,the ratio of time spent in the target quadrant was increased,Aβ expression in prefrontal cortex and hippocampus was down-regulated and Tau protein expression in prefrontal cortex and hippocampus was up-regulated in group SS (P < 0.05 or 0.01).Conclusion Sirolimus can significantly improve scopolamine-induced cognitive dysfunction in rats and the changes in the expression of Aβ and Tau protein in prefrontal cortex and hippocampus may be involved in the mechanism.
8.Prevalence and genotypes of Chlamydia psittaci in pigeons in Jilin Province, Northeastern China
Qiuxia YAO ; Xiaoxuan ZHANG ; Kai CHEN ; Jiangang MA ; Wenbing ZHENG ; Xiaoqin XU ; Xingquan ZHU
Chinese Journal of Zoonoses 2017;33(2):104-109
Chlamydia psittaci is a causative agent of psittacosis,which can infect a wide range of hosts including birds and humans.However,information regarding C.psittaci infection in pigeons is scarce.In the present study,a total of 399 fecal samples from pigeons were collected from Jilin Province,northeastern China,between March and May 2015,and examined by nested PCR amplification of outer membrane protein A (ompA) gene.The overall Chlamydiosis prevalence was 5.01% (21/399),with 3.19% in Changchun City and 9.40% in Jilin City.Furthermore,breed was the major risk factor associated with Chlamydia infection in pigeon,boiler pigeons had a prevalence of 7.49%,whereas no C.psittaci was detected in racing pigeons.Sequence analysis of the ompA gene revealed that all the identified isolates represented C.psittaci genotype B.Our results firstly indicated the presence of zoonotic C.psittaci in boiler pigeons in Jilin Province,northeastern China,and effective measures should be implemented to reduce the risk of C.psittaci transmission from pigeons to humans.
9.Compatible Stability of Carbohydrate-Electrolyte Injection and Commonly Used Vitamin-Electrolyte Injections
Lan XU ; Jizhi CHEN ; Xiaoxuan TAO ; Chuanhua FENG ; Gang LI ; Jing ZHANG
Herald of Medicine 2016;35(5):526-529
Objective To study the compatible stability of the carbohydrate-electrolyte injection and commonly used vitamin-electrolyte injections. Methods By simulating clinical use of medicines,the carbohydrate-electrolyte injection and various vitamin-electrolyte injections were mixed respectively.The content of sodium acetate was measured by HPLC,and changes in appearance,pH value and insoluble particles of the injections were observed. Results At room temperature,the compatibility solutions showed no significant changes in appearance,pH value,the number of insoluble particles and the content of sodium acetate within 8 h. Conclusion The carbohydrate-electrolyte injection is compatible with commonly used vitamin-electrolyte injections,and the admixtures are stable within 8 h at room temperature.
10.Determination of Total Phenylethanoid Glycosides and Acteoside in Plantago Herba
Chuanhua FENG ; Qi REN ; Xiaolin TANG ; Man YI ; Lan XU ; Xiaoxuan TAO ; Lang ZHANG ; Gang LI
China Pharmacist 2017;20(8):1477-1479
Objective: To determine total phenylethanoid glycoside and acteoside in Plantago Herba to provide reference for evaluating the quality of medicinal materials.Methods: With acteoside as the control sample, a UV visible spectrophotometric method was used to determine total phenylethanoid glycosides in Plantago Herba.An HPLC method was applied to determine acteoside in Plantago Herba , and the conditions were as follows: an ODS2 C 18 (150 mm× 4.6 mm ,5 μm) chromatographic column was used with acetonitrile-0.1% formic acid (13∶87) as the mobile phase at a flow rate of 1.0 ml·min-1 , the detection wavelength was 332nm, the column temperature was 30℃, and the sample volume was 10 μl.Results: The reference solution and the sample solution had the maximum absorption at 332 nm, and the linear relationship was good within the range of 0.003 1-0.155 0 mg·ml-1 (r=0.999 5).The content of total benzene alcohol glycosides in 3 batches of samples was 2.73% , 2.61% and 2.84% , respectively;acteoside over the range of 0.000 6-0.155 0 mg·ml-1 (r=0.999 1) showed a good linear relationship with peak area,the sample recovery was 98.5% and the RSD was 1.6% (n =6), and the acteoside content in 3 batches of samples respectively was 0.54% , 0.51% and 0.56%.Conclusion: The method is simple, accurate and reproducible, and can be used for the determination of total phenylethanoid glycosides and acteoside in Plantago Herba.