1.A discussion about how to prevent and control adverse event of medical device based on metal materials science
China Medical Equipment 2017;14(4):51-54
Objective: To discuss the effect of metal materials science for how to prevent and control adverse events of medical devices, and provide forewarning measures for preventing this kind of events. Methods: To analyze the adverse events report of medical devices, and summarize 10 kinds of fault phenomenon and clinical manifestation of adverse events came from metal materials, such as respiration device and its accessories, color ultrasonic imaging device and ultrasound intervention, intracavity diagnosis and implants, and so on. To analyze the reason of the medical equipment accidents;and provide countermeasures for monitoring and management of adverse events of medical devices. Results: The advantages of preventing and controlling adverse events of medical equipment based on metal material science were:①monitor the metal material performance changes occur in force or strain and early alarming, ②identify implanted medical consumables degradation. Conclusion: The fatigue damages and defects of metal materials were the main reason of medical device adverse events. The hospital needs to establish the medical device adverse event reporting, evaluation model, evaluation and classification of time report supervision mechanism; establish and improve the monitoring and management mechanism, technical personnel and regulations; perfect the corresponding technical support system, and achieve monitoring and risk management for adverse events of clinical medical devices.
2.Hypothesis and application of bimolecular marking methods in Chinese materia medica.
Lu-qi HUANG ; Dan QIAN ; Chao DENG
China Journal of Chinese Materia Medica 2015;40(2):165-168
Based on the current shortage of genuine/false authentication and quality evaluation in the molecular identification, and the weak functional gene research in the establishment of two-dimensional molecular markering methods for Chinese materia medica, the authors proposed a new method, the bimolecular marking methods (BIMM) for Chinese materia medica, combining DNA marker and metabolomics marker, that could simultaneously research the species and quality differences at the molecular level at the present stage. The authors introduced the concept, principle, methods, and technical process of BIMM, and summarized the technical advantages in this paper. Meanwhile, the application of BIMM in the identification of multiple sources of Chinese materia medica, years-identification, different locations, elite germplasm research, discovery of new drugs resources, protection of new varieties was also discussed. As a supplement of two-dimensional molecular markering method for Chinese materia medica, BIMM would not only expand connotation of identification of Chinese materia medica but also provide another effective way for quality evaluating.
Genetic Markers
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Materia Medica
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Medicine, Chinese Traditional
3.Sinus histiocytosis with massive lymphadenopathy
Dan LI ; Lihong REN ; Chao YI
Chinese Pediatric Emergency Medicine 2015;22(2):123-125
Sinus histiocytosis with massive lymphadenopathy( SHML) is also called Rosai-Dorfman disease.It is a kind of benign lymphoid tissue proliferative diseases with unknown etiology.SHML appeared mostly in children and adolescent.It has diverse clinical manifestations accompanied with multiple organ inju-ry,and no clear laboratory indicators could support the disease,being a rare disease in pediatrics,easyot miss diagnosis.Thsi article reviewde the latest progress on diagnostis and treatment of SHML,to improve teh un-derstanding of the disease.
4.Comparison of rabbit retinal fixation techniques: chemical fixation and microwave irradiation
Chao, QU ; Dan, WANG ; Wen-dong, WANG ; Ying-chun, LI ; Dan-dan, DONG ; Ying-chuan, FAN
Chinese Journal of Experimental Ophthalmology 2011;29(1):17-20
Background Conventional chemical method to fix the entire eyeball results in the edema of retinal nerve fiber layer and therefore influent the evaluation of tissue structure.Research showed that microwave irradiation can avoid this phenomenon. Objective This study was to investigate the appropriate energy and time duration of microwave irradiation for fixation of rabbit eyes specimen and compare the influence of different fixation methods on retinal structure. Methods Twenty-two New Zealand white rabbits were sacrificed by using venous air embolism.The eyeballs were enucleated from the rabbits and immersed in chemical reagents with glacial acetic acid,methyl aldehyde and chloroform for 2 days as the control group.The eyeballs were immersed in 400 ml physiological balance solution immediately,and then were fixed by microwave irradiation for 80,160,240 and 320 seconds under the lower power as the microwave irradiation groups.In the microwave irradiation+chemical fixation group,the specimens were immersed in chemical reagents for 1-2 hours after the microwave radiation.The morphology of retinal structure was examined and area of retinal detachment was calculated by hemotoxylin and eosin staining under the light microscope. Results A better fixation effect was obtained in the retinal section of microwave radiation for 240 seconds in comparison with that of the traditional chemical reagent fixation method for 2 days.The retina detachment ratio was 16.3%±11.5% for simple microwave method,50.0%±24.5% for chemical method,and 6.7%±7.8% for microwave+chemical method.showing a significant difference among 3 groups(F=32.43,P=0.000).Retinal staining was clear and retinal structure was almost normal in the specimens of microwave+chemical fixation group with 200-240 seeonds microwave irradiation and 1-2 hours chemical fixation. Conclusion Microwave irradiation method is a more ideal way for the fixation of retina because of taking short duration,lower toxicity and better staining.The combination of microwave radiation and chemical reagents can acquire an excellent quality of retinal section.
5.Study on in vitro release consistency between self-prepared Torasemide Sustained-Release Tablet and original preparation
Yan HAN ; Chao MA ; Dan YANG ; Ce MENG ; Xiaowen REN
Drug Evaluation Research 2017;40(2):174-178
Objective To establish a method for determining the dissolution oftorasemide sustained-release tablet in vitro and study the methodology of the determination.The consistency of the in vitro release behavior between self-prepared torasemide sustained-release tablet and original preparation were evaluated by constructed method.Methods HPLC method was applied to detect the cumulative release percentage of self-prepared torasemide sustained-release tablet and original preparation in five kinds of release media (water,0.1 mol/L hydrochloric acid solution,pH 4.5 acetate buffer,pH 6.8 phosphate buffer,and 0.1 mol/L hydrochloric acid solution turn to pH 6.8 phosphate buffer).Similarity factor (f2) was used to evaluate the similarity of release curves.Results There was a good linear relationship between the quality concentration of torasemide and peak area in the range of 1.0-12.0 μg/mL (r =0.9995).Results of precision and stability tests were good,and the RSDs for probational liquid were all lower than 2.0%.The average recovery of accuracy test was 100.04%,and RSD was 0.54% (n =12).The homogeneity of within group of self-prepared preparation met the technical requirement,RSDs of each sampling points in six Dissolution Vessels were lower than 10.0%.The f2 factors of self-prepared torasemide sustained-release tablet and original preparation were 72,60,77,66,and 60 in five kinds of release media.Conclusion The method in the paper is suitable for the release test of torasemide,meanwhile,the self-prepared tablet shows consistent in vitro release behavior with that of the original preparation.
6.Principles of biowaiver about consistency evaluation of generic drug products and varieties of biowaiver in countries and international organizations
Dan YANG ; Chao MA ; Xinyi CHEN ; Boying CHEN ; Xiaowen REN
Drug Evaluation Research 2017;40(2):157-163
Objective For bioequivalence test of the consistency evaluation of generic drug products,providing a reference of varieties of biowaiver.Methods Based on Human bioequivalence test waiver guidelines (draft),on condition that first drug of the consistency evaluation,to introduce and conclude briefly the standards of biowaiver and varieties of biowaiver in FDA,WHO and EMA.Results Contrast to FDA,there are 59 varieties applied for the waiver and 19 varieties not applied for the waiver in the 289 varietie;compared to WHO,10 drugs are exempted and 1 grug is exempted in EMA.Conclusion At present,the specific list of drugs are not published of biowaiver in our country,the pharmaceutical companies should compare and consult revelant standards and specific drugs in China and abroad,to speed up the progress of the consistency evaluation.
7.Construction of three-dimensional finite element model with lateral mass screw fixation following lower cervical three-segment laminectomy
Mingzhi SONG ; Chao DONG ; Dan LI ; Kai MA
Chinese Journal of Tissue Engineering Research 2014;(35):5640-5646
BACKGROUND:With the improvement of cervical posterior surgical techniques, lateral mass screw fixation technology has been widely used in the reconstruction surgery of the cervical spine for stability. However, currently, the finite element study on the lateral mass screw fixation reconstruction of the cervical spine is rare. OBJECTIVE:To establish a fine normal lower cervical spine (C3-C7 ) three-dimensional finite element model and a reconstructed finite element model with three-segment laminectomy with lateral mass screw fixation. Then, to do an initial biomechanical analysis of the lateral mass screw fixation reconstructed lower cervical finite element model. METHODS:We col ected a normal female volunteer aged 30 years old to do CT scan for the whole cervical spine. The Dicom data were obtained. Then, the CT scanning images were dealt with software Mimics 10.01, Geomagic Studio 12.0, Solidworks2012, HyperMesh 10.1 and Abaqus 6.12 software to build the normal lower cervical spine (C 3-C7 ) finite element model, the laminectomy finite element model and the rebuilt finite element model. At last, we analyzed the stress changes of reconstructed models under the state of flexion, extension, lateral bending and rotational motion. RESULTS AND CONCLUSION:The lower cervical spine finite element model contained 503 911 elements and 93 390 nodes with a fine realistic appearance. It successful y passed the validation. The surgical procedure was completed in the software, and the lateral mass screw fixation reconstruction finite element model has been established. Lateral mass screw fixation system provides good stability for the postoperative finite element model. The activity of rebuilt finite element model is much lower than the normal finite element model. In the extension condition, the stress of lateral mass screw fixation system becomes strong.
8.Expression, purification and immunogenicity analysis of recombinant MPB64 using baculovirus expression system
Dan XU ; Chao JIANG ; Yu CHEN ; Jun AI ; Xiaoyan WANG ; Xiaokun LI
Chinese Journal of Immunology 2014;(7):921-926
Objective:To express mycobacterium tuberculosis protein MPB 64 in baculovirus insect cell expression system ,and identify its immunogenicity.Methods:The target gene MPB64 was connected to pFastBac vector ,then the pFastBac-MPB64 plasmid which was harvested would transformed to DH10Bac competent,and the target gene was transposition into Bacmid by Tn7 transposase fragment,therefore Bacmid-MPB64 Shuttle vector was obtained.The shuttle vector was packaged by liposomes and transfected Sf 9 cells to harvest P1-generation virus ,then high titers of P4 generation virus was harvested by repeat transfected Sf 9 cells three times.The target protein MPB64 was purified from the supernatant by Q Sepharose FF and Ni affine chromatography ,which were used to immunize BALB/c mice.Antibody changes in serum would be detected ,and the proliferation of immunized mice spleen cells would be detected by MTT,detected the IFN-γsecretion by MPB64 stimulated spleen cells by ELISA method.Results: MPB64 successfully expressed in insect cells.The purity of target protein was over 90% and yield up to 35 mg/L after purification.Purified protein can effectively stimulate BALB/c mice to produce antibodies , increase the content of IFN-γmedium in mice spleen cells ,and significantly promoting proliferation in spleen cells between 0.2-100 μg/ml.Conclusion: MPB64 which has immunogenicity was successfully expressed in baculovirus insect cell expression system ,that open a new avenue for tuberculosis vaccine production.
9.Immunosuppresive, antioxidative, anti-inflammatory and analgesic effect of Xiahuoluo pills
Jingqiang PAN ; Liuying XIAO ; Dan ZHANG ; Chao HAN ; Jieru LIN ; Linying ZHENG ; Boping LI
Chinese Journal of Tissue Engineering Research 2006;10(47):183-188
BACKGROUND: Xiaohuoluo pill can expel pathogenic wind, remove dampness and activate collaterals. It is used for treatment of Bi-syndrome due to wind-cold-dampness, pain and numbness in limbs.OBJECTIVE: To observe the pharmacological effect of Xiaohuoluo pills on secondary immune response, specific immunity (including cellular immunity and humoral immunity), non-specific immunity [including complement 3(C3), mononuclear phagocyte system (MPS) and red blood cell (RBC)adhesion function] and free radical injury as well as pain and many other inflammations in mice.DESIGN: A randomized controlled stratified trial.SETTING: Guangzhou Institute of Traditional Chinese Medicine and Chinese Materia Medica; Department of Pharmacy, Guangzhou Hospital of Traditional Chinese Medicine.MATERIALS: Totally 628 NIH and ICR mice of 6 to 8 weeks were involved in this trial. Xiaohuoluo pills (components: Dannanxing, Zhichuanwu, Zhicaowu, Dilong, Ruxiang and so on; Chenli Pharmaceutical Factory,Guangzhou; Brach No. 19980612) were used in this trial. Rabbit antimouse immunoglobulin G (IgG) and C3 antiserum reagent kit (Guangzhou Institute of Medicine and Health) and reagent kit for measuring the antioxidizing activity of superoxide dismutase (SOD) and the level of malondialdehyde (MDA) (Jiancheng Institute of Bioengineering, Nanjing) were used.METHODS: This trial was carried out in the Guangzhou Institute of Traditional Chinese Medicine and Chinese Materia Medica; Department of Pharmacy, Guangzhou Institute of Medicine and Health during September 1998 to December 1999. ① To observe the suppressive effect of Xiaohuoluo pills on cock red blood cell (CRBC)-induced secondary immune response: Eight-four ICR mice, male and female in half, were selected.Twenty of 84 mice served as blank controls; The other 64 mice were intraperitoneally injected with cyclophos-phamide (CY) of 0.2 g/kgonce. On the 4th and 12th days, CRBC was intraperitoneally injected into the mice twice to induce immunoenhancing pathological models to form secondary immune response. Mice served as blank controls were intraperitoneally injected with the same volume of normal saline; The immunoenhanced mice were assigned into 3 groups by a lot: CY group (n=20, CY, 40 mg/kg, intragastric administration, I.g.), Xiaohuoluo pills (n=21, Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) and model group (n=20, distilled water, the same volume as other groups, I.g.); once a day within 7 successive days. 19 days later, the levels of serum IgG and C3 were measured with single immunodiffusion method, and the level of circulating immune compound (CIC) was measured with polyethylene glycol precipitation method. ② To observe the suppressive effect of Xiaohuoluo pills on delayed type hypersensitivity (DTH): Fifty-four ICR mice, male and female in half, were selected. On the 1st day, the mice were sensitized by subcutaneous injection of 10 g/L 2,4-dinitrofluorobenzen e (DNFB) of 50 μL for each. On the 4th day, the sensitized mice were assigned into 3 groups by a lot: Prednisone group (n=18, prednisone, 0.01 g/kg, I.g.), Xiaohuoluo pills (n=18, Xiaohuoluo pills suspension, 5.54 g/kg, I.g.), model group (n=18, distilled water, the same volume as other groups, I.g.), all once a day within 7 successive days. 11 days later, 10 g/L DNFB of 25μL was spread on the right ear of each mouse in each group. The swelling degree was calculated 24 hours later (The mass difference between right ear and left ear). ③ To observe the suppressive effect of Xiaohuoluo pills on immune adhesion function of RBC of mouse: Thirty-six NIH mice, male and female in half, were selected and assigned into 3 groups by a lot: CY group (n=12, CY, 20 mg/kg,I.g.), Xiaohuoluo pills (n=12, Xiaohuoluo pills suspension, 5.54 g/kg, I.g.)and blank control group (n=12, distilled water, the same volume as other groups, I.g.), once a day within 7 successive days. 7 days later, blood was taken from the orbit of mice for calculating the rosette rate of RBC-C3b receptor and the rosette rate of RBC immune compound. ④ To observe the suppressive effect o20 Mg/kg, I.g.),Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) , once a day within 7 successive days; IgM-type hemolytic concentration (HC50)was measured at 2 hours after the last administration on the 7th day [ (Sample absorption / Absorption at HC50 of CRBC) ×diluted time]. The levels of serum C3 and MDA and the activity of SOD were measured according to the method from corresponding reagent kit. ⑥ To observe the suppressive effect of Xiaohuoluo pills on agar granulation tissue hyperplasia in mice:Fifty-nine NIH mice were selected and given subcutaneous injection of 20 g/L agar of 0.5 mL for each. 24 hours later, the mice were assigned into 3 groups by a lot: diclofenac group (diclofenac, 10 mg/kg,I.g..), Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) and model group (distilled water, the same volume as other groups, I.g.), once a day within 7 successive days; On the 8th day, the mice were sacrificed. The hyperplasiainhibiting effect was presented in the form of the mass of agar granulation tissue in one kilogram body mass ⑦ To observe the suppressive effect of Xiaohuoluo pills on acetic distortion reaction: Sixty-three NIH mice were se lected and assigned into 3 groups by a lot: diclofenac group (diclofenac,50 mg/kg, I.g.), Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg,I.g.) and model group (distilled water, the same volume of other groups, I.g.),once a day within 2 successive days. At 2 hours after the last administration, the mice were given intraperitoneal injection of 0.1 mol/L acetic acid of 0.2 mL for each one. The times of distortion of mice within 20 minutes were counted. ⑧ To observe the effect of Xiaohuoluo pills on the acute exudative inflammation evoked by dimethylbenzene, croton oil and carrageenan, and the level of prostaglandin E in the inflammatory exudates:Totally 219 NIH mice were selected and assigned into 3 groups by a lot:diclofenac group (diclofenac, 50 mg/kg, I.g.), Xiaohuoluo pills group (Xiaohuoluo pills suspension, 5.54 g/kg, I.g.) and model group (distilled water, the same volume of other groups, I.g.) once a day within 2 successive days. At 2 hours after the last administration, dimethylbenzene of 25 μL was spread on the right ear for 20 minutes, or croton oil of 25 μL was also spread on the right ear, 4 hours later, the swelling of right ear was calculated (mass of right ear-mass of left ear). 10 g/L carrageenan of 20 μL was subcutaneously injected into the right foot, 3 hours later, the swelling degree was calculated (The difference of right foot and left foot); and the level of prostaglandin E in the inflammatory exudates was measured. ⑨ t test(t' test for heteroscedasticity) was used for comparing the difference in measurement data among groups.MAIN OUTCOME MEASURES: Pharmacological effect of Xiaohuoluo pills on secondary immune response, specific immunity, non-specific immunity and free radical injury as well as pain and many other inflammations in mice.RESULTS: Totally 628 NIH and ICR mice were involved in result analysis. ① The level of IgG and CIC of mice in the model group was significantly higher than that in the other 3 groups respectively (P < 0.01),while the level of C3 was significantly lower than that in the other 3 groups (P < 0.05 to 0.01). ② The swelling degree of mice in the diclofenac group and Xiaohuoluo pills group was significantly lower than that in the blank control group respectively ( both P < 0.01). ③ The rosette rate of RBC-C3b receptor and RBC immune compound in the blank control group was significantly higher than that in the other 2 gro ups respectively (P < 0.01). ④ The phagocytic index (K value )in the diclofenac group and Xiaohuoluo pills group was significantly lower than that in the blank control group, respectively (both P < 0.01).⑤ IgM-type HC50 and the level of serum MDA of CY group and Xiaohuoluo pills group were obviously lower than those in the immune control group (P < 0.01),while the level of C3 was higher than that of immune control group, there was no significant difference in the activity of serum SOD between CY group or Xiaohuoluo pills group and immune control group (P > 0.05). ⑥The ratio of agar granulation tissue mass to body mass in the diclofenac group or Xiaohuoluo pills group was significantly lower than that in the model group(P < 0.01).⑦ The times of distortion of mice within 20 minutes in the diclofenac group or Xiaohuoluo pills group were signifi cantly less than those of model group(P < 0.01,0.05).⑧The ear swelling degree of dimethylbenzene-induced inflammatory models and croton oil-induced inflammatory models,and foot swelling degree of carrageenan-induced acute inflammatory models as well as the level of prostaglandin E in the inflammatory exudates in the diclofenac group were significantly milder or lower than those in the model group(P < 0.05 to 0.01),and the level of prostaglandin E in the inflammatory exudates in the Xiaohuoluo pills group was significantly lower than that in the model group (P < 0.01).CONCLUSION: Xiaohuoluo pills possess pharmacological effects of immunosuppression, anti-proliferative inflammation, analgesia and antioxidation.
10.Effects of porcine bone protein on serum phosphorus level and bone mineral density in a rat model of osteoporosis
Yuhui AN ; Siyu HE ; Dan SONG ; Fengchun LI ; Chao ZHANG ; Hongli MAO ; Qian ZHANG
Chinese Journal of Tissue Engineering Research 2010;14(33):6253-6257
BACKGROUND: Several studies have demonstrated that many American women who are at high risk of developing osteoporosis have higher levels of serum phosphorus. This indicates that some substances which can lower the serum level of phosphorus will supply a new and effective method to prevent and treat osteoporosis.OBJECTIVE: To observe the influences of porcine bone protein on bone mineral density (BMD) and serum levels of calcium and phosphorus in a rat model of osteoporosis.METHODS: Wistar rat models of osteoporosis were established by intramuscular injection of dexamethasone. Rat models were randomly divided into physiological saline, Jiegu Qili tablet, 50, 100, 200 mg/kg porcine bone protein groups. Rats that did not receive any treatments served as normal controls. After 12 weeks of treatment, serum was collected and serum levels of phosphorus and calcium were determined by biochemistry method. At the same time, tibia sections were made to determine tibial DMD by QDR-400 dual energy X-ray absorptiometry and to observe tibia marrow cavity by hematoxylin-eosin staining.RESULTS AND CONCLUSION: There was no significant difference in serum level of calcium among groups (P>0.05).Compared with the physiological saline group, serum level of phosphorus in the 50, 100, 200 mg/kg porcine bone protein groups was significantly decreased (P < 0.05). BMD was significantly higher in the 50, 100, 200 mg/kg porcine bone protein, Jiegu Qili tablet groups than in the physiological saline group (P < 0.05). The tibia marrow cavity was smallest in the normal control group and largest in the physiological saline group. The tibia marrow cavity was larger in the 50, 100, 200 mg/kg porcine bone protein,Jiegu Qili tablet groups than in the physiological saline group. These results indicate that porcine bone protein cannot change the serum level of calcium, but it lowers serum level of phosphorus, and increases BMD, in a rat model of osteoporosis. However, the dose-dependent effect of porcine bone protein was not observed within the present experimental dosage. In addition, porcine bone protein can also reduce the marrow cavity of the tibia of rats with osteoporosis.