Objective To study the need for blood compatibility evaluation of medical devices that come into indirect contact with blood in order to accurately evaluate the risk of their interaction with blood.Methods Seven medical devices with indirect contact with blood were selected as samples including extension tubes of central venous catheters,port bodies of implantable drug delivery devices,infusion sets,receiving lines of dialysis equipment,auxiliary lines of left ventricular assist devices,blood monitors and catheter holders,with high-density polyethylene as the negative control,glass beads as the positive control and blank whole blood or plasma for the blank control.Partial thromboplastin time(PTT)test,platelet count test and hematology test(white blood cell and red blood cell count)were performed by direct contact method and indirect contact method,respectively.In the direct contact method,whole blood or plasma was in direct contact with the sample;while in the indirect contact method,whole blood or plasma was not in direct contact with the extraction solution,with no direct contact with the sample.Results With the indirect contact method the ratios(expressed as a percentage)of the PTT,platelate,WBC and RBC counts of the samples,positive and negative controls to those of the blank control were all higher than those with the direct contact method,and the indirect contact method had the sensitivity lower than that of the direct contact method.Conclusion Medical devices indirectly contacting blood have low risks for causing coagulation and platelet and hematologic adverse reactions,which are suggested to be evaluated for hemolysis testing only in case of the history of safe clinical use.[Chinese Medical Equipment Journal,2025,46(8):44-49]

Objective:To analyze the epidemiological and clinical characteristics of respiratory pathogens in China.Methods:This study was a cross-sectional study, which encompassed 19 core units of the clinical pathogen network and established a three-tiered clinical pathogen surveillance system. Thirty respiratory samples were collected every two weeks from various units from January to December 2024, and the clinical and pathogen diagnostic information were gathered. A total of 11 864 samples were tested using this system. The tier-1 clinical pathogen surveillance system covered influenza A virus (Flu-A), influenza B virus (Flu-B), respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The tier-2 clinical pathogen surveillance system focused on 18 key respiratory pathogens. The tier-3 clinical pathogen surveillance system further clarified whether any emerging infectious diseases had occurred.Results:The tier-1 clinical pathogen surveillance system showed Flu-A predominated in December, Flu-B predominated in January, SARS-CoV-2 peaked in March and August, whereas RSV circulated sporadically throughout the year. Geographic trends were broadly consistent across the seven major regions, although Flu-A detection in December was notably higher in Northeast China (48.1%(111/231)) and East China (36.2%(148/409)), and RSV detection was concentrated in the Northwest and South China from January to March. Data from the tier-2 clinical pathogen surveillance system indicated that Streptococcus pneumoniae, Mycoplasma pneumoniae, rhinovirus, and adenovirus were detected year-round, of these, Streptococcus pneumoniae and rhinovirus showed elevated positive detection rates from August to September, while adenovirus peaked in January. Legionella pneumophila was not detected throughout the year, and other pathogens fluctuated throughout the year without a consistent pattern. The predominant etiologic agents of pediatric pneumonia were Mycoplasma pneumoniae (35.0%(105/300)), rhinovirus (25.7%(77/300)), and adenovirus (17.3%(52/300)), whereas adult pneumonia was mainly caused by Streptococcus pneumoniae (10.5%(29/277)), Staphylococcus aureus (6.9%(19/277)), Mycoplasma pneumoniae (6.9%(19/277)), and Flu-A (6.1%(17/277)). The tier-3 clinical pathogen surveillance system did not identify any emerging respiratory pathogens. Conclusion:Respiratory pathogens in China in 2024 exhibit distinct temporal and spatial distribution patterns and vary among different populations.

Objective To propose an in vitro cytotoxicity evaluation method for novel iron-based biodegradable mateirals focusing on their degrading characteristics.Methods Half-finished scaffolds of nitrided iron tubes with a higher iron content of over 99％and a nitrogen content of 0.03％to 0.20％were selected as test samples,and based on the treatment mode were divided into an anaerobic treatment group,a non-anaerobic treatment group,a non-anaerobic treatment with removed iron particle group and a non-anaerobic treatment with plate-washing group.The anaerobic treatment group was processed in an anaerobic workstation;the conventional treatment group underwent standard handling in a biosafety cabinet;the conventional treatment with removed iron particle group was subjected to iron particle elimination using a Midimacs Starting Kit manual sorter after conventional treatment;and the conventional treatment with plate-washing group was rinsed with 0.9％sodium chloride injection before tetrazolium salt reagent treatment.Different extraction media(simulated body fluid,cell culture medium,phosphate buffer and 0.9％sodium chloride injection)were used for the immersion treatment of the test samples in each group to compare the effects of the degradation products on the survival rate of L929 cells.Results The anaerobic treatment group and the conventional treatment with removed iron particle group exhibited no detectable cytotoxicity.Trypan blue staining revealed significant cytotoxicity in the conventional treatment group,while false-negative results emerged due to interactions between the tetrazolium salt reagent and degradation products.In the non-anaerobic treatment with washing plate group,the false negative from iron particles was eliminated while potential cytotoxicity was showen,and the result accuracy was affected because some cells were washed out.Conclusion The proposed method can be used for the in vitro cytotoxicity evaluation,and facilitates the safety evaluation of the application of such materials.[Chinese Medical Equipment Journal,2025,46(3):35-41]

Objective:An in vivo mammalian hepatocyte Unscheduled DNA Synthesis(UDS)test was used to evaluate the genotoxicity of Cross-linked Sodium Hyaluronate Gel and Bone Repair Materials,providing experimental evidence for establishing a UDS testing method for medical devices and materials.Methods:0.9％sodium chloride injection and cottonseed oil were used as the solvent for test materials and negative control,respectively.N-dimethylnitrosamine(NDMA)was used as the positive control for the early sampling times,and 2-acetylaminofluorene(2-AAF)was used as the positive control for the late sampling times.SD rats were administered a single dose for toxic exposure,and liver tissues were collected at 4 h and 16 h,respectively.Hepatocytes were isolated using collagenase perfusion.After labeling with 5-ethynyl-2'-deoxyuridine(EdU),and the net average fluorescence intensity(NAFI)of cell nuclei and nucleoplasm was measured by fluorescence microscope.Data from 50 cells were used to analyze the DNA repair level.Results:Compared with the negative control groups,the positive control groups(NDMA and 2-AAF)showed highly statistically significant differences in NAFI(P＜0.01),indicating successful induction of DNA damage.There was no statistically significant differences between the cross-linked sodium hyaluronate gel groups,bone repair material groups and the negative control group(P＞0.05),suggesting that these materials did not significantly induce DNA damage under the experimental conditions.Conclusion:This study first applied EdU labeling technology to the in vivo hepatic UDS assay,achieving non-radioactive labeling through click chemistry reactions.Under the conditions of this study,cross-linked sodium hyaluronate gel and bone repair materials did not exhibit genotoxicity.In the follow-up,the sample range can be expanded and the observation period can be prolonged to further improve the genotoxicity evaluation system of medical devices.

Objective To evaluate the subchronic systemic toxicity of disposable plasma virus-inactivated blood transfusion sets using hydroxyethyl starch(HES)130/0.4 sodium chloride injection as an extraction medium.Methods Firstly,40 Sprague Dawley(SD)rats including 20 male and 20 female ones were seleted and randomly enrolled into a sample group and a control group by sex,with 20 ones in each group.Secondly,instead of plasma HES 130/0.4 sodium chloride injection was used to leach disposable plasma virus-inactivated blood transfusion sets to prepare the test solution by simulating clinical application such as lighting,adsorption and filtration and storage.Finally,the test solution and HES 130/0.4 sodium chloride injection were injected into the tail vein of the SD rats at a dose of 20 mL/kg for 28 d in the sample group and in the control group respectively,and the subchronic systemic toxicity of disposable plasma virus-inactivated blood transfusion sets and the feasibility of using HES 130/0.4 sodium chloride injection as the extraction medium to assess their subchronic systemic toxicity were evaluated with clinical observation,body mass monitoring,clinical pathology examination,gross necropsy and histopathology examination.Results The sample group and control group had no significant differences in mortality rates,clinical observation results,body mass,gross necropsy results,hematological and coagulation examination results and organ weight(all P>0.05);blood biochemical examinations showed the male rats in the sample group had the cholesterol(CHO)values higher while the creatinine(CR)values lower than those in the control group,with the differences being statistically significant(both P<0.05)and the two indexes within the range of the laboratory's historical reference data,and other blood biochemical indexes were not significantly different(all P>0.05);the sample group had the spleen weight-to-body mass ratios of the female rates lower significantly than those in the control group(P<0.05),and the ratios of other organ weight to body mass had significant differences(all P>0.05);histopathology examination showed slight pathological changes in liver,spleen and kidney of female rats and in spleen and kidney of male rats in the sample group,and the female and male rats in the control group had similar pathological changes found in the sample group,which might be caused by HES metabolites.Conclusion Disposable plasma virus-inactivated blood transfusion sets prove to have no significant subchronic systemic toxicity,and its feasible to use HES 130/0.4 sodium chloride injection as the extraction medium to evaluate the subchronic systemic toxicity of disposable plasma virus-inactivated blood transfusion sets.[Chinese Medical Equipment Journal,2025,46(10):29-35]

Objective To propose an in vitro cytotoxicity evaluation method for novel iron-based biodegradable mateirals focusing on their degrading characteristics.Methods Half-finished scaffolds of nitrided iron tubes with a higher iron content of over 99％and a nitrogen content of 0.03％to 0.20％were selected as test samples,and based on the treatment mode were divided into an anaerobic treatment group,a non-anaerobic treatment group,a non-anaerobic treatment with removed iron particle group and a non-anaerobic treatment with plate-washing group.The anaerobic treatment group was processed in an anaerobic workstation;the conventional treatment group underwent standard handling in a biosafety cabinet;the conventional treatment with removed iron particle group was subjected to iron particle elimination using a Midimacs Starting Kit manual sorter after conventional treatment;and the conventional treatment with plate-washing group was rinsed with 0.9％sodium chloride injection before tetrazolium salt reagent treatment.Different extraction media(simulated body fluid,cell culture medium,phosphate buffer and 0.9％sodium chloride injection)were used for the immersion treatment of the test samples in each group to compare the effects of the degradation products on the survival rate of L929 cells.Results The anaerobic treatment group and the conventional treatment with removed iron particle group exhibited no detectable cytotoxicity.Trypan blue staining revealed significant cytotoxicity in the conventional treatment group,while false-negative results emerged due to interactions between the tetrazolium salt reagent and degradation products.In the non-anaerobic treatment with washing plate group,the false negative from iron particles was eliminated while potential cytotoxicity was showen,and the result accuracy was affected because some cells were washed out.Conclusion The proposed method can be used for the in vitro cytotoxicity evaluation,and facilitates the safety evaluation of the application of such materials.[Chinese Medical Equipment Journal,2025,46(3):35-41]

Objective:An in vivo mammalian hepatocyte Unscheduled DNA Synthesis(UDS)test was used to evaluate the genotoxicity of Cross-linked Sodium Hyaluronate Gel and Bone Repair Materials,providing experimental evidence for establishing a UDS testing method for medical devices and materials.Methods:0.9％sodium chloride injection and cottonseed oil were used as the solvent for test materials and negative control,respectively.N-dimethylnitrosamine(NDMA)was used as the positive control for the early sampling times,and 2-acetylaminofluorene(2-AAF)was used as the positive control for the late sampling times.SD rats were administered a single dose for toxic exposure,and liver tissues were collected at 4 h and 16 h,respectively.Hepatocytes were isolated using collagenase perfusion.After labeling with 5-ethynyl-2'-deoxyuridine(EdU),and the net average fluorescence intensity(NAFI)of cell nuclei and nucleoplasm was measured by fluorescence microscope.Data from 50 cells were used to analyze the DNA repair level.Results:Compared with the negative control groups,the positive control groups(NDMA and 2-AAF)showed highly statistically significant differences in NAFI(P＜0.01),indicating successful induction of DNA damage.There was no statistically significant differences between the cross-linked sodium hyaluronate gel groups,bone repair material groups and the negative control group(P＞0.05),suggesting that these materials did not significantly induce DNA damage under the experimental conditions.Conclusion:This study first applied EdU labeling technology to the in vivo hepatic UDS assay,achieving non-radioactive labeling through click chemistry reactions.Under the conditions of this study,cross-linked sodium hyaluronate gel and bone repair materials did not exhibit genotoxicity.In the follow-up,the sample range can be expanded and the observation period can be prolonged to further improve the genotoxicity evaluation system of medical devices.

Objective To evaluate the subchronic systemic toxicity of disposable plasma virus-inactivated blood transfusion sets using hydroxyethyl starch(HES)130/0.4 sodium chloride injection as an extraction medium.Methods Firstly,40 Sprague Dawley(SD)rats including 20 male and 20 female ones were seleted and randomly enrolled into a sample group and a control group by sex,with 20 ones in each group.Secondly,instead of plasma HES 130/0.4 sodium chloride injection was used to leach disposable plasma virus-inactivated blood transfusion sets to prepare the test solution by simulating clinical application such as lighting,adsorption and filtration and storage.Finally,the test solution and HES 130/0.4 sodium chloride injection were injected into the tail vein of the SD rats at a dose of 20 mL/kg for 28 d in the sample group and in the control group respectively,and the subchronic systemic toxicity of disposable plasma virus-inactivated blood transfusion sets and the feasibility of using HES 130/0.4 sodium chloride injection as the extraction medium to assess their subchronic systemic toxicity were evaluated with clinical observation,body mass monitoring,clinical pathology examination,gross necropsy and histopathology examination.Results The sample group and control group had no significant differences in mortality rates,clinical observation results,body mass,gross necropsy results,hematological and coagulation examination results and organ weight(all P>0.05);blood biochemical examinations showed the male rats in the sample group had the cholesterol(CHO)values higher while the creatinine(CR)values lower than those in the control group,with the differences being statistically significant(both P<0.05)and the two indexes within the range of the laboratory's historical reference data,and other blood biochemical indexes were not significantly different(all P>0.05);the sample group had the spleen weight-to-body mass ratios of the female rates lower significantly than those in the control group(P<0.05),and the ratios of other organ weight to body mass had significant differences(all P>0.05);histopathology examination showed slight pathological changes in liver,spleen and kidney of female rats and in spleen and kidney of male rats in the sample group,and the female and male rats in the control group had similar pathological changes found in the sample group,which might be caused by HES metabolites.Conclusion Disposable plasma virus-inactivated blood transfusion sets prove to have no significant subchronic systemic toxicity,and its feasible to use HES 130/0.4 sodium chloride injection as the extraction medium to evaluate the subchronic systemic toxicity of disposable plasma virus-inactivated blood transfusion sets.[Chinese Medical Equipment Journal,2025,46(10):29-35]

Objective To study the need for blood compatibility evaluation of medical devices that come into indirect contact with blood in order to accurately evaluate the risk of their interaction with blood.Methods Seven medical devices with indirect contact with blood were selected as samples including extension tubes of central venous catheters,port bodies of implantable drug delivery devices,infusion sets,receiving lines of dialysis equipment,auxiliary lines of left ventricular assist devices,blood monitors and catheter holders,with high-density polyethylene as the negative control,glass beads as the positive control and blank whole blood or plasma for the blank control.Partial thromboplastin time(PTT)test,platelet count test and hematology test(white blood cell and red blood cell count)were performed by direct contact method and indirect contact method,respectively.In the direct contact method,whole blood or plasma was in direct contact with the sample;while in the indirect contact method,whole blood or plasma was not in direct contact with the extraction solution,with no direct contact with the sample.Results With the indirect contact method the ratios(expressed as a percentage)of the PTT,platelate,WBC and RBC counts of the samples,positive and negative controls to those of the blank control were all higher than those with the direct contact method,and the indirect contact method had the sensitivity lower than that of the direct contact method.Conclusion Medical devices indirectly contacting blood have low risks for causing coagulation and platelet and hematologic adverse reactions,which are suggested to be evaluated for hemolysis testing only in case of the history of safe clinical use.[Chinese Medical Equipment Journal,2025,46(8):44-49]

Objective:To analyze the epidemiological and clinical characteristics of respiratory pathogens in China.Methods:This study was a cross-sectional study, which encompassed 19 core units of the clinical pathogen network and established a three-tiered clinical pathogen surveillance system. Thirty respiratory samples were collected every two weeks from various units from January to December 2024, and the clinical and pathogen diagnostic information were gathered. A total of 11 864 samples were tested using this system. The tier-1 clinical pathogen surveillance system covered influenza A virus (Flu-A), influenza B virus (Flu-B), respiratory syncytial virus (RSV), and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The tier-2 clinical pathogen surveillance system focused on 18 key respiratory pathogens. The tier-3 clinical pathogen surveillance system further clarified whether any emerging infectious diseases had occurred.Results:The tier-1 clinical pathogen surveillance system showed Flu-A predominated in December, Flu-B predominated in January, SARS-CoV-2 peaked in March and August, whereas RSV circulated sporadically throughout the year. Geographic trends were broadly consistent across the seven major regions, although Flu-A detection in December was notably higher in Northeast China (48.1%(111/231)) and East China (36.2%(148/409)), and RSV detection was concentrated in the Northwest and South China from January to March. Data from the tier-2 clinical pathogen surveillance system indicated that Streptococcus pneumoniae, Mycoplasma pneumoniae, rhinovirus, and adenovirus were detected year-round, of these, Streptococcus pneumoniae and rhinovirus showed elevated positive detection rates from August to September, while adenovirus peaked in January. Legionella pneumophila was not detected throughout the year, and other pathogens fluctuated throughout the year without a consistent pattern. The predominant etiologic agents of pediatric pneumonia were Mycoplasma pneumoniae (35.0%(105/300)), rhinovirus (25.7%(77/300)), and adenovirus (17.3%(52/300)), whereas adult pneumonia was mainly caused by Streptococcus pneumoniae (10.5%(29/277)), Staphylococcus aureus (6.9%(19/277)), Mycoplasma pneumoniae (6.9%(19/277)), and Flu-A (6.1%(17/277)). The tier-3 clinical pathogen surveillance system did not identify any emerging respiratory pathogens. Conclusion:Respiratory pathogens in China in 2024 exhibit distinct temporal and spatial distribution patterns and vary among different populations.