Lung Examination in Systemic Toxicitytest of Medical Devices / 中国医疗器械杂志

The lung is an important organ in systemic toxicity test of medical devices and is significant in safety evaluation. Based on the authors' understanding of medical devices, this study provides a brief analysis of the lung examination and common problems in systemic toxicity, so as to provide references for the pre-clinical safety evaluation of medical devices. It should be noted that a reasonable risk assessment should be made after comprehensive assessment for specific medical device products.

Research Method of Fatigue Performance of Surgically Implanted Heart Valve Stent / 中国医疗器械杂志

The aim of this study was to evaluate the fatigue property

Quality Control and Safety Evaluation of Culture Medium for Human Assisted Reproduction / 中国医疗器械杂志

OBJECTIVE@#In this paper, the key points of quality control and safety evaluation of human assisted reproductive medium were summarized to provide reference for the establishment of relevant standards and quality control in the future.@*METHODS@#Through literature research, the key factors of quality control and risk control of human assisted reproductive medium were summarized, and the problems in clinical transformation were discussed.@*RESULTS@#It is very important for the development of human assisted reproduction technology to study the active ingredients and their harmful degradation products and drugs in the culture medium of assisted reproduction.@*CONCLUSIONS@#At present, the biggest challenge is to effectively control the quality of the culture medium for human assisted reproduction, establish corresponding inspection methods and quality standards for the key components, ensure the safety and effectiveness during the product shelf life, and thus improve the success rate of human assisted reproduction technology.

Quality Control of Appliance Products of Medical Devices for Human Assisted Reproductive Technology / 中国医疗器械杂志

Infertility has become one of the global problems, with the continuous improvement and penetration of human assisted reproductive technology, appliance products of medical devices for assisted reproductive technology, such as aspiration needles, micromanipulator and embryo transfer catheter, have been widely used. In order to ensure the safety and effectiveness of such products, it is necessary to establish an appropriate quality control system. This paper mainly discusses the quality control points of human assisted reproductive medical devices from the aspects of raw materials, product design, production process, key performance, packaging, preservation and transportation, so as to provide technical reference for the research and development, production and supervision of such products.

Safety of Alginate-based Gastric Mucosal Protective Adhesive and Feasibility Study of Its Use as Submucosal Injection / 中国医疗器械杂志

OBJECTIVE@#To study the safety of alginate based gastric mucosal protective adhesive and its feasibility as a submucosal injection.@*METHODS@#The feasibility of using alginate-based gastric mucosal protective gel as submucosal injection was evaluated by @*RESULTS@#After injection of different concentrations of alginate base mucosal protective adhesive solution, the uplift height was significantly higher than that of normal saline (@*CONCLUSIONS@#Gastric mucosa protector is a promising new medical device product with feasibility and good biocompatibility as submucosal uplift injection agent.

The Embryo Toxicity Research of Manufacturing Water of Medical Device of in Vitro Fertilization Technology / 中国医疗器械杂志

Water is an important component in liquid medical device products for human assisted reproductive technology. Water traits, conductivity, microbial limits, total organic carbon, easy oxides, heavy metal content, bacterial endotoxin and other indicators have an important impact on sperm, egg and embryo development in vitro, so for such products, the quality of water control is extremely important. The production water for producing such products is generally prepared by MilliQ purification system. In this research, we used four different types of water to fabricate the IVF liquids. It included deionized reverse osmosis water, ultra purified water and ultra purified water without endotoxin or nucleic acid, and compared with tap water. The in vitro rat embryo test system was used to study the embryotoxicity of this four different culture liquid production waters. From the result, the group of the super purified water without endotoxin and nucleic acid has the best result of the embryo formation rate, the number of total cell number and the inner cell number. This study proved the importance of removing endotoxin and nucleic acid from the water used for the preparation of the liquid products for assisted reproduction, and provided the basis for the selection of water quality for the liquid products for assisted reproduction.

Research Progress of Skin-substitute and Its Effectiveness Evaluation / 中国医疗器械杂志

Skin-substitute has developed rapidly and it is essential to evaluate its effectiveness before clinical use.This paper reviews the development of skin-substitute,methods to evaluate the effectiveness of skin-substitute and relevant standards.This paper highlights the and means of preclinical effectiveness evaluation and provides theoretical basis for preclinical safety evaluation of skin-substitute.

Ultrahigh performance liquid chromatography-tandem mass spectrometry determination of glutamine in human assisted reproductive medium / 中国组织工程研究

BACKGROUND: Ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for analyzing amino acids in biological samples is simple in sample preparation with a short analysis time, and has high sensitivity and specificity. Until now, it is only applied in analyzing glutamine contents in dialysate, urine and plasma. OBJECTIVE: To establish a method for determining glutamine concentration in human assisted reproductive media by UPLC-MS/MS. METHODS: The UPLC separation was performed on a SUPELCO Discovery HS F5-3 column (15 cm×2.1 mm, 3 μm) at 40 oC. The mobile phase was acetonitrile and water (both containing 0.1％ formic acid) in a gradient elute mode. The flow rate was 0.35 mL/min. Electrospray ionization with a negative-ion and multiple reaction monitoring mode was used. RESULTS AND CONCLUSION: The linearity was achieved in the range of 0.123 7-24.74 mg/L for glutamine (r=0.999 7). The recoveries were 102.9％-108.2％ with the range 2.3％-4.9％ for the relative standard deviation. The limit of qualification was 9.76 μ g/L. The fertilization culture medium containing glutamine was incubated at 37 oC for 96 hours, in which the glutamine content declined 6％ at 24 hours and 15％ at 96 hours respectively compared with initial content. Therefore, the method is simple, specific, accurate and sensitive without sample derivation, and the test time is short. It is suitable for the quality control of human assisted reproductive media and useful for the risk study related to the degradation of glutamine.

Tissue Fluid Enzyme-Linked Immunosorbant Assay for Piglets Experimentally Infected with Toxoplasma gondii and Survey on Local and Imported Pork in Korean Retail Meat Markets

To investigate the prevalence of Toxoplasma gondii in pork on the market in Korea, an in-house enzyme-linked immunosorbent assay for tissue fluid (CAU-tf-ELISA) was developed using a soluble extract of T. gondii RH strain tachyzoites. As the standard positive controls, the piglets were experimentally infected with T. gondii: Group A (1,000 cysts-containing bradyzoites), Group B (500 cysts-containing bradyzoites) and Group C (1.0×103 or 1.0×104 tachyzoites). The CAU-tf-ELISA demonstrated infection intensity-dependent positivity toward tissue fluids with average cut-off value 0.15: 100% for Group A, 93.8% for Group B and 40.6% for Group C. When tissue-specific cut-off values 0.066–0.199 were applied, CAU-tf-ELISA showed 96.7% sensitivity, 100% specificity, 100% positive and 90.0% negative predictive values. When compared with the same tissue fluids, performance of CAU-tf-ELISA was better than that of a commercial ELISA kit. Of the 583 Korea domestic pork samples tested, anti-T. gondii antibodies were detected from 9.1% of whole samples and 37.9% from skirt meat highest among pork parts. In the 386 imported frozen pork samples, 1.8% (skirt meat and shoulder blade) were positive for anti-T. gondii antibodies. In Korea, prevalence of anti-T. gondii antibodies in the pork on retail markets appeared high, suggesting that regulations on pig farming and facilities are necessary to supply safe pork on the tables.

Bioresorbable Vascular Scaffold: A Focused Review on Development and Preclinical Studies / 中国医疗器械杂志

Bioresorbable vascular scaffolds(BVS) are new treatment strategies of percutaneous coronary intervention. They have been introduced to overcome limitations of bare metal stents (BMS) and drug-eluting stents(DES), since they provide temporary scaffolding and then disappear, liberate the treated vessel from cage. In this article, we review the current status and problems of BVS, various tests required before gaining regulatory approval for clinical use.

Cell Count of Mouse Blastocyst on Pre-clinical Evaluation of Safety of Medical Devices in Assisted Reproductive Technologies / 中国医疗器械杂志

Various types of medical devices used in assisted reproductive technologies (ART) should be detected for their safety by strict biological assays. Mouse embryo assay(MEA)has been recognized as one of the most important and standardized methods with the threshold more than 80% of blastocyst formation rate (BR) after 96 h culture of fertilized eggs. The disadvantage using BR for embryonic quality control has been concerned as it is ubiquitously dependent of embryonic morphology and the detailed data including molecular and genetic information is obviously missing and incomplete. This leads to the urgent requirement for more sensitive and efficient assessments for the quality control of ART. This study evaluated the reliability of an immunofluorescent MEA by counting total cell and differential number of the cells in the inner cell mass (ICM) and trophectoderm (TE) in the blastocyst. This method improved the traditional MEA, provided a sensitive and powerful platform to assess embryonic developmental viability and should be suggested as a standard assay to be globally used for the quality control of medical devices and pre-clinical procedures in ART.

Analysis of factors affecting the standardization of in vitro mouse embryo test / 中国比较医学杂志

Infertility has become a global problem affecting human reproductive health.As an important treatment for infertility, assisted reproductive technology has made great progress over the past few decades.Rapid development has also taken place in medical devices for human assisted reproductive technology.It is imperative to establish the risk management and safety evaluation system of these products.In 2016, the industry standard YY/T 1434-2016 Human in vitro Assisted Reproductive Technology With Medical Equipment in vitro Mouse Embryo Test was officially released.In this paper, the key notes and elements of this in vitro mouse embryo test are briefly reviewed.

Simultaneous determination of three main bioactive constituents in the in vitro fertilization medium by UHPLC-MSMS / 中国组织工程研究

BACKGROUND:In the present quality control file or technique standards of in vitro fertilization medium, the indicators of the component contents and detection methods have not been clearly defined. To ensure the safety and effectiveness of these products, we should establish the quality standards as early as possible. OBJECTIVE:To establish a method for determining the three main bioactive constituents of in vitro fertilizationmedium including glucose, lactic acid sodium salt, pyruvic acid sodium salt by ultra-high performance liquid chromatography tandem mass spectrometric method (UHPLC-MSMS), and to analyze the content of each constituent. METHODS:The UHPLC-MSMS was used, and UHPLC separation was performed on a SUPELCO Discovery HS F5-3 column (15 cm × 2.1 mm, 3μm) in a gradient elute mode with acetonitrile and water (both containing 0.1%formic acid) as the mobile phase at a flow rate of 0.35 mL/min. The column temperature was 40℃. Mass spectrometry detection was performed with multi-reaction monitoring mode using negative electro spray ionization. RESULTS AND CONCLUSION:The linearity was achieved in the range of 0.1-10μg/mL (r=0.999 8) for glucose, 0.05-5μg/mL (r=0.999 4) for lactic acid sodium salt, and 0.1-10μg/mL (r=0.999 4) for pyruvic acid sodium salt. The recoveries were 96.4%-98.1%with relative standard deviation less than 2.8%. To conclude, the UHPLC-MSMS method is sensitive, rapid, accurate and specific, thus providing a basis for the quality standard study of in vitro fertilization medium.

Toxicity of blastula culture medium to mouse embryos: a safety evaluation ofinvitro assisted reproduction devices / 中国组织工程研究

BACKGROUND:The blastula culture medium can assist the development of zygote from the fertilized egg to the blast blastula. The safety and quality of blastula culture medium directly influences the quality of blastula. OBJECTIVE:To evaluate the effect of blastula culture medium on the development of mouse embryos. METHODS: In this study, B6D2F1 mice were used. The female mice were superovulated and mated with male B6D2F1 mice. One day later, the zygotes were colected and cultured in the M16 medium to 4-cel stage. Then, 4-cel stage embryos were transferred into the tested blastula culture medium (experimental group). After 5 days of culture, the forming rate of blastula was examined. Meanwhile, the M16 medium containing endotoxin was used to culture 1-cel mouse zygote (positive control group). The M16 medium with no embryo toxicity was used to culture 1-cel zygote (negative control group). RESULTS AND CONCLUSION:The formation rate of blastula was 0 in the positive group, 87.1% in the negative control group, and 87.3% in the experimental group. From the results, the tested blastula culture medium could assist the 1-cel zygote growing to the stage of blastula, and the formation rate of blastula was above 80%. The tested blastula culture medium had no toxicity to the mouse embryo.

Application of tissue engineering scaffolds in neural repair / 中国组织工程研究

BACKGROUND:Tissue engineering scaffolds can create proper nerve regeneration microenvironment, enrich nutritional factors for nerve regeneration and promote axonal growth. OBJECTIVE:To review the progress of tissue engineering scaffolds in nerve repair in recent years. METHODS:A computer-based retrieval was performed to search ful-text articles addressing tissue engineering scaffolds used to repair nerve damage published from 2009 to 2014 in PubMed databases using the keywords of “nerve regeneration, prostheses and implants” as wel as articles published from 2004 to 2014 in CNKI database using the keywords of “nerve repair, material” in Chinese. RESULTS AND CONCLUSION: Currently, scaffold materials for nerve damage mainly include natural materials, naturaly derived materials, synthetic materials and composites, al of which have their own advantages and disadvantages. By chemical crosslinkers or chemical modification, the naturaly derived polymer can be combined with other natural or synthetic composite materials, to improve their physicochemical and biological properties, i.e., the composite scaffolds have better effects than single materials in nerve regeneration. Therefore the current research focus is composite materials. In clinical research, colagen scaffold for nerve repair has entered the clinical research stage.

Magnetic resonance compatibility research for coronary mental stents / 中国医疗器械杂志

The objective of this article is to research magnetic resonance compatibility for coronary mental stents, and to evaluate the magnetic resonance compatibility based on laboratory testing results. Coronary stents magnetic resonance compatibility test includes magnetically induced displacement force test, magnetically induced torque test, radio frequency induced heating and evaluation of MR image. By magnetic displacement force and torque values, temperature, and image distortion values to determine metal coronary stent demagnetization effect. The methods can be applied to test magnetic resonance compatibility for coronary mental stents and evaluate its demagnetization effect.

The reproductive toxicity of rat models implanted with copper-bearing intrauterine device at teratogenic sensitive period by continuous extraction method / 中国组织工程研究

BACKGROUND:At present, the copper-bearing intrauterine device, a kind of class III medical devices, is commonly used in China. However, there is no clear conclusion about whether it has impact on the embryo or fetus in some cases, such as unexpected pregnancy during long-term implantation and pregnancy in a short time after removing it. OBJECTIVE: To evaluate the safety of copper-bearing intrauterine device by observing the influence of copper-bearing intrauterine device extracts on pregnant rats and rat fetuses by tail vein injection in the sensitive period of teratogenesis. METHODS: A total of 60 fertilized rats were divided into control group, high dosage group, middle dosage group, and low dosage group. The copper-bearing intrauterine device extracts were prepared by the continuous extraction method. Different concentrations (0.2, 0.1, 0.05 g/mL) of copper-bearing intrauterine device extracts were injected by the tail vein at the 1st day of pregnancy in the latter three groups at a dosage of 0.01 mL/g per day. The control group was given the same amount of normal saline. The injection lasted for 20 days. Then, the pregnant rats were sacrificed to measure body mass, check both sides of the uterus and internal organs, isolate fetal rats, as wel as record the quality of uterus and fetal rats, corpus luteum, implantation numbers, the number of stilbirths, then number of live births and the number of fetal absorption. The fetal rats were determined in the folowing aspects: body mass, body height, tail length, the ossification degree and appearance of the occipital bone, bone and visceral anomalies. RESULTS AND CONCLUSION: The number of births, implantation numbers, the number of live births, the number of corpus luteum, the percentages of live births and stilbirths, the number of resorbed fetuses, and the weight of uterus and fetal rats in the control group showed no difference from those in the other three groups (P > 0.05). No malformation in the internal organs occurred. Compared with the control group, the high, middle and low dosage groups showed no difference in the height, tail length, body mass, and ossification degree of the occipital bone of fetal rats (P > 0.05). No malformation in the appearance, skeleton and internal organs occurred in the fetal rats. These findings indicate that there were no maternal toxicity, abnormal embryonic growth or rat fetus anomalies after injecting copper-bearing intrauterine device extracts into pregnant rats in sensitive period of teratogenesis.

Alpha-Gal antigen and immunity risk control of animal-derived medical devices / 中国组织工程研究

BACKGROUND:Medical devices from animals are commonly used in clinical application. Despite their efficiency is widely accepted, their safety, especialy immunity has been concerned. OBJECTIVE:To investigate immunity risk control to medical devices from animals for safety consideration. METHODS:Using “α-Gal antigen, immunity, xenotransplantation” in Chinese and English as the key words, the first author conducted a computer search of Science direct database (www.sciencedirect.com), Wiley-Blackewel database (http://onlinelibrary.wiley.com) and Wanfang database (www.wanfang.com.cn) through screening the titles and abstracts. RESULTS AND CONCLUSION:Increasing evidence shows that, Gal α1-3Gal antigen (α-Gal antigen) is recognized as the major antigen and abundantly expressed on glycoconjugates of non-primate mammals and New World monkeys. In contrast, the α-gal epitope is not expressed on glycoconjugates of humans and Old World monkeys. Instead, they produce a very large amount of natural anti-α-Gal antibody that specificaly binds the α-gal epitope. The binding of human natural anti-α-Gal to α-gal epitopes expressed on non-primate mammal animals was expected to be unique immunological barrier in xenotransplantation. Therefore, it is important to choose raw materials, reduce or eliminate the α-Ggal epitope, establish highα-Ggal epitope detection methods with high sensitivity and good repeatability for achieving a greater safety and efficiency of medical devices from animals.

The current situation and suggestions on the institutes for medical devices test in China / 中国医疗器械杂志

This paper introduces the current status of Chinese medical device testing and inspection institutes. There are 53 such institutions, including 10 national institutions. Medical device testing and inspection institutions service in government regulation and supervision of medical devices, playing a technique support role for medical devices from registration before appear on market to monitor and supervision after listing. Meanwhile, they are important practitioners of medical devices standardization work. Finally, put forward the current problems and countermeasures of the inspection institutes in order to facilitate the sustainable development of our national medical equipment.

The preparation and bioactivity assessment of gene recombinant fibrin-binding brain derived neurotrophic factor / 生物医学工程学杂志

Using the E. coli, we fabricated the gene reconstructed brain derived neurotrophic factor with a fibrin binding domain (FBD-BDNF). We then tested the neurotrophic bioactivity and fibrin-binding ability of the FBD-BDNF. The E. coli was used to express the recombinant protein. The inclusion body was purified with column chromatography and renaturated to construct the right 3D formation. In this study, we successfully fabricated the FBD-BDNF and tested the binding ability and neurotrophic activity. The results demonstrated that FBD-BDNF had special binding ability of fibrin and significant neurotrophic activity for DRG cells. FBD-BDNF could have a promising application prospect in nerve tissue engineering.