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.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.
6.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.
7.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.
8.Knowledge and behaviors about hepatitis B prevention and control among carriers of hepatitis B surface antigen
LI Siwen ; ZHOU Tiantian ; ZHANG Chao ; ZHANG Dan ; HU Weijun
Journal of Preventive Medicine 2025;37(3):253-256,261
Objective:
To investigate the knowledge and behaviors related to hepatitis B prevention and control among carriers of hepatitis B surface antigen (HBsAg), so as to provide the basis for conducting health education and interventions for HBsAg carriers.
Methods:
Based on the seroepidemiological survey of hepatitis B among individuals aged 1 to 69 years in Shaanxi Province, HBsAg carriers were selected as the study subjects. Basic information, knowledge and behaviors about hepatitis B prevention and control were collected through questionnaire surveys. The awareness of hepatitis B prevention and control knowledge and related behaviors among HBsAg carriers were analyzed.
Results:
A total of 107 HBsAg carriers were enrolled, including 52 males (48.60%) and 55 females (51.40%), and had a median age of 47.04 (interquartile range, 19.78) years. The awareness of hepatitis B prevention and control knowledge ranged from 56.07% to 87.85% among HBsAg carriers, with the highest awareness for "hepatitis B vaccination can effectively prevent hepatitis B "(87.85%), and the lowest awareness for "sharing meals with HBsAg carriers or hepatitis B patients will not lead to infection" (56.07%) and "hepatitis B can be treated with antiviral drugs" (61.68%). The proportions of those who did not seek medical consultation, undergo regular check-ups, or receive treatment were relatively high, at 65.42%, 72.90% and 77.57%, respectively.
Conclusions
The awareness of hepatitis B transmission routes and treatment-related knowledge among HBsAg carriers is relatively low, and their medical-seeking behaviors are relatively passive. There is a need to enhance the dissemination of hepatitis B prevention and control knowledge, improve medical-seeking behaviors, and reduce the risk of hepatitis B virus transmission.
9.Experimental study of the monitoring bias of pressure in intubation balloon using handheld pressure gauge
Yanxia LIN ; Dan LIN ; Biqun CHEN ; Chao JI ; Congli YUAN ; Baochun WANG
Chinese Critical Care Medicine 2014;26(5):347-350
Objective To explore the bias between the real pressure and the measured values when handheld pressure gauge (HPG) was used to monitor intermittently the pressure in the intubation balloon,so as to provide some measures for the correct use of HPG.Methods In the first part of the study,HPG was used to measure the pressure with the balloon connected with a three-way tube with which to control the inflation and deflation in a laboratory to measure the pressure in the air bag.After gaining the deviation in this in vitro experiment,it was tested and verified in vivo in adult patients undergoing endotracheal intubation.Results After 132 times of measurements,it was found that measurement with a HPG might result in an inherent loss (3.928 ± 0.291) cmH2O (1 cmH2O=0.098 kPa,t =155.273,P =0.000) between inflation value [(30.000 ± 0.000) cmH2O] and measured value [(26.072 ± 0.291) cmH2O].In addition,after 214 times repeated measurements,the pressure loss during disconnection of the gauge was as high as (1.196 ± 0.954) cmH2O (t=18.348,P=0.000) between filled values [(30.000 ± 0.000) cmH2O] and measured values [(28.804 ± 0.954) cmH2O] and it was named as error loss.At last,the total error was verified by clinical test,and it was (5.270 ± 2.583) cmH2O (t=29.632,P=0.000) between pressure of filled value [(30.000 ± 0.000) cmH2O] and measured value [(24.730 ± 2.583) cmH2O].Conclusions When the balloon pressure was Monitored intermittently with HPG,the real value should be the measured value plus the error.In addition,subglottic aspiration should be done before the connection of the balloon to the gauge to prevent the secretions on the cuff falls into the deeper airway,and to maintain the cuff pressure at 30 cmH2O.
10.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.