Objective To develop a time-resolved fluorescent immunoassay kit for the rapid,accurate and quantitative detection of S100B protein in serum and to evaluate its performance.Methods The test strip was prepared using time-resolved fluorescent microsphere-labeled anti-S100B polyclonal antibody and rabbit IgG antibody,labeling pads,sample pads,S100B nitrocellulose films and absorbent paper,and an S100B time-resolved fluorescence immunoassay kit was obtained by assembling the cartridge.The performance of the kit developed was evaluated by standard curve,accuracy,minimum detection limit,linear interval,specificity,reproducibility and stability.The reference intervals of 199 pieces of healthy human serum and plasma samples from a certain region were detected with the kit,and the clinical performance of the kit and Roche Elecsys S100 kit was tested by synchronous blind method to assess the consistency of the results of the two kits for 142 samples.Results The S100B time-resolved fluorescence immunoassay kit had the standard curve beingy=(1.133 02+1.752 24)/[1+(x/1.082 20)×(-0.603 52)]-1.752 24,R2=0.999 08 and the linear range being[0.05,30]ng/mL,which met the requirements of the relative deviation of the accuracy within±15％,the minimum detection limit not hgier than 0.05 ng/mL,the relative deviation of specificity within±15％and the coefficient of variation of intra-and inter-batch difference less than 15％.The stability test results indicated that the kit was valid for 12 months at 2-30 ℃ conditions.The reference intervals of serum and plasma samples measured by the kit were both lower than 0.3 ng/mL.Clinical trials showed that the results by the kit and Roche Elecsys S100 Assay Kit were in high agreement(Kappa=0.906 1＞0.80)and met the requirements.Conclusion The kit developed detects the concentration of S100B protein in serum quickly,accurately and quantitatively,and provides references for the diagnosis and treatment of neurological diseases,autoimmune diseases,cerebrovascular diseases and etc.[Chinese Medical Equipment Journal,2024,45(1):47-55]

Objective To establish a stable and reliable method for the determination of ethylene oxide residue,and to analyze ethylene oxide residue in multi components made of different materials involved in some medical devices,so as to provide references for sample selection and ethylene oxide residue detection of multi-component medical device kits.Methods A method for the determination of ethylene oxide residue of multi-component medical devices was developed using headspace-gas chromatography and DB-WAX column under the conditions of headspace extraction with equilibration at 80℃ for 20 min,and the weighing mass,linearity,limit of detection,limit of quantification,precision and recovery of the method were determined.Trials of the method were carried out on the items undergoing ethylene oxide sterilization,including disposable perineal care kit,disposable gynecological examination kit,disposable suture dressing kit,disposable debridement kit and the components contacting human body in the disposable dialysis kit,and the abilities of different materials of the components were analyzed in absorbing,retaining and releasing ethylene oxide.Results The method showed high linearity(r=0.999 8)in the range of ethylene oxide mass concentration from 0.4 to 16.0 μg/mL with a weighing mass of 1.00 g,which had the limit of detection being 0.11 μg/mL,the limit of quantification being 0.37 μg/mL and the relative standard deviations(RSDs)for the precision from 0.35％to 1.52％.The average recoveries of different spiked amounts of ethylene oxide in the three blank matrices ranged from 92.68％to 101.42％with the relative standard deviations(RSDs)from 2.46％to 7.59％,which all satisfied the detection requirements.The components made of rubber and acrylonitrile-butadiene-styrene copolymer(ABS)in multi-component medical device kits had the highest ethylene oxide residues,followed by the components made of wood,degreased cotton,polypropylene and polystyrene.Conclusion The method proposed gains advantages in easy operation and high specificity,quantification and reproducibility,which can be used for the determination of ethylene oxide residue in the multi-component medical device kit undergoing ethylene oxide sterilization.References are provided for sample selection of multi-component medical devices.[Chinese Medical Equipment Journal,2024,45(1):56-61]

Objective To investigate the expressions of 12 cytokines(IL-1β,IL-2,IL-4,IL-5,IL-6,IL-8,IL-10,IL-12p70,IL-17,IFN-α,IFN-γ,TNF-α)and procalcitonin in patients with infective endocarditis(IE).Methods Ten IE patients admitted to our hospital from December 2021 to December 2022 were included into the IE group,10 patients with non-infectious and non-rheumatic valvular diseases who were admitted to our hospital at the same period were randomly selected as the control group,and blood sampling of all patients were conducted at admission.The expressions of 12 cytokines and blood routine indexes were detected by flow cytometry,and the level of procalcitonin was detected by ELISA.The correlations among the expression levels of cytokines in IE patients were analyzed by Pearson method and the correlations of IL-8 level and white blood cell count with procalcitonin in IE patients were analyzed by Spearman method.Results Compared with the control group,the levels of cytokines of IL-1β,IL-2,IL-6,IL-10,TNF-α,IFN-α,IFN-γ and IL-12p70 in the IE group were significantly increased(P<0.05),the white blood cell count,neutrophil percentage and procalcitonin were significantly increased(P<0.05).There was no significant difference in the percentage of monocytes between the two groups(P>0.05).IFN-α of IE patients was positively correlated with IL-2,TNF-α,IL-1β and IL-12p70,IL-2 was positively correlated with TNF-α and IL-1β,IL-12p70 was positively correlated with IFN-γ,and procalcitonin was significantly positively correlated with IL-8 and white blood cell count,with statistically significant differences(P<0.05).Conclusion The levels of IL-1β,IL-2,IL-6,IL-10,TNF-α,IFN-α,IFN-γ,IL-12p70 and procalcitonin in IE patients are significantly higher than those in the normal population,and the detections of these indicators are of guiding significance for the early diagnosis of IE and the evaluation of the severity of the disease.

The clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) is widely used for targeted genomic and epigenomic modifications, transcriptional regulation and real-time cell imaging, and has already demonstrated great potential for applications in agriculture, industry and medicine. The promise of the technology depends upon the five intrinsic properties of CRISPR/Cas: targeting, target unwinding, target cutting, target residence, and collateral cleavage. Here, mainly using Streptococcus pyogenes CRISPR/Cas9 as example, we will focus on the target residence of CRISPR/Cas in applications of the CRISPR/Cas technology, summarize the recent progress, and discuss the effect of CRISPR/Cas target binding and residence on DNA double strand break repair pathway choices and the opportunities that CRISPR/Cas target residence presents to optimize the CRISPR/Cas technology.

Objective To analyze the changes of B lymphocyte(B cells)subsets in peripheral blood of patients with chronic hepatitis B(CHB)and to explore its clinical significance.Methods Peripheral blood samples were collected from 37 treatment-na?ve CHB patients who were admitted to the Fifth Medical Center of PLA General Hospital from July 2022 to October 2022,and peripheral blood samples collected from 18 healthy individuals who have received the hepatitis B vaccine as healthy controls(HC).The study subjects'clinical indexes such as age,HBV DNA viral load,HBsAg quantification,HBeAg semi quantification,ALT,AST,and AST/ALT ratio were collected.The change characteristics of the frequency,phenotypic and functional markers of peripheral blood B lymphocytes and their subsets were compared between CHB and HC.Using multi-color flow cytometry,and the correlation between them and clinical indexes was analyzed.Results Frequency analysis of each subset of B cells showed that compared with HC,the frequency of total B cells,transitional B cells and naive B cells was decreased(P<0.05),while the frequency of mature B cells,memory B cells,atypical memory B cells and activated memory B cells was increased in CHB patients(P<0.01).And there was no significant difference in the frequency of resting memory B cells between the two groups(P>0.05).The results of functional analysis showed that compared with HC,the expression levels of CD79b on total B cells,mature B cells,memory B cells,naive B cells,activated memory B cells,atypical memory B cells and resting memory B cells in CHB patients were increased(P<0.05).The expression level of programmed cell death protein-1(PD-1)on atypical memory B cells in CHB patients was also higher than that in HC group(P<0.05).The results of correlation analysis showed that the frequency of total B cells in CHB patients was slightly negatively correlated with age(r=-0.39,P<0.05),while the expression of programmed death-1(PD-1)on total B cells,mature B cells,transitional B cells,memory B cells and naive B cells were slightly positively correlated with age(r>0.36,P<0.05).Conclusions Chronic HBV infection leads to depletion of the frequency and function of a portion of B cells in the peripheral blood of CHB patients,and age is a potential risk factor for the decline in humoral immune function in CHB patients.

Chimeric antigen receptor(CAR)T cell therapy,one of the most promising tumor treatments,combines the targeted recognition of antigen and antibody with the killing effect of T cells.CAR-T has shown a strong therapeutic effect in lymphoid tumors and been applied in clinical practice.However,in the treatment of acute myeloid leukemia(AML),no effective and specific target like CD 19 in lymphoid tumors has been found.Therefore,the key research direction is to try multiple probabilities and use optimization strategies to enhance efficacy and reduce toxicity.This review introduces the latest research progress of AML targets in CAR-T therapy in recent years,analyzes the related problems that need to be solved at present,and summarizes the optimization construction strategies mentioned in the research.Hope it can provide reference for related research and clinical application of related product.

Objective To propose an effective method for the determination of 2-chloroethanol(ethylene chlorohydrin,ECH)and ethylene glycol(EG)residues in disposable infusion sets sterilized by ethylene oxide(EO).Methods Extraction with the ratio of the mass of the disposable infusion set to the volume of the medium being 0.4 g/mL was carried out with the 8890B gas chromatograph with liquid injection,DB-WAX column and ethanol extraction medium,and quantitative determination of ECH and EG in disposable infusion sets were implemented after extraction at 37℃for 10 h.Results The method proposely was highly specific,and showed high linearity in the range of 1.25-100.00 μg/mL for both ECH and EG.The limits of detection were 0.31 and 0.11 μg/mL for ECH and EG,respectively,and the relative standard deviations(RSD)of the precision of ECH was in the range of 0.24％-2.03％and those of EG was in the range of 0.16％-0.87％.The average recoveries were 95.02％-100.58％for ECH and 99.15％-99.98％for EG.Conclusion The method proposed for the determination of ECH and EG residues gains advantages in easy operation,specificity,detection accuracy and reproducibility,and meets the requirements for the determination of ECH and EG residues in EO-sterilized disposable infusion sets.[Chinese Medical Equipment Journal,2024,45(10):31-36]

Objective To investigate the titer stability of the harvest solution of severe acute respiratory syndrome coronavirus2(SARS-CoV-2)at 2 ～ 8 ℃ and the inactivation effect of β-propiolactone inactivator on the virus.Methods Three batches of SARS-CoV-2 harvest solution(batch numbers:202111001,202111002 and 202111003)were stored at 2 ～ 8 ℃ for 12 d and sampled every 3 d(0,3,6,9 and 12 d)for detection of the titers by Karber method;Three batches of virus harvest solution equilibrated overnight at 2 ～ 8 ℃ were inactivated by adding β-propiolactone at a volume fraction of 1∶4 000 and detected for the titers at different inactivation time points(0,0.5,1,1.5,2,3,4,8,16 and 24 h),of which samples inactivated for 8,16 and 24 h were taken for inactivation verification,and samples inactivated for 24 h were observed by transmission electron microscope.Results The titers of SARS-CoV-2 decreased with the prolongation of storage time at 2 ～8 ℃,which showed no obvious decrease during 0 ～ 3 d,while decreased from the initial 7.75,6 and 7.5 lgCCID_(50)/mL to5.75,4.625 and 6.25 lgCCID_(50)/mL on day 12,indicating that the virus activity showed a gradual decrease trend at 2 ～8 ℃；With the inactivation time,the virus titer decreased continuously and could not be detected after inactivation for 3 h.Transmission electron microscope observation showed that the inactivated virus particles were intact and the spike protein was evenly distributed.Conclusion The virulence of SARS-CoV-2 stored at 2 ～ 8 ℃ was unstable,so the subsequent inactivation and purification process should be carried out as soon as possible;The titer of virus could not be detected after3 h of inactivation,which provided a reference for the determination of the inactivation process.

ObjectivesBased on the changes of lung lesions in patients with COVID-19 at different stages， a nomogram model describing CT image features was established by radiomics method to explore its efficacy in predicting the progression of the disease. MethodsThis retrospective study enrolled 136 patients with COVID-19 pneumonia who received at least two CTs including three cohorts （training cohort and validation cohort 1 and 2）. Patients in the training cohort were divided into three groups according to time between onset of fever symptoms and the first CT. The clinical manifestations and CT features of each group were analyzed and compared. A nomogram to predict disease progression was constructed according to the CT features of the patients， and its performance was evaluated. ResultsThe training cohort consisted of 41 patients.A nomogram was generated to predict disease progression based on three CT features： irregular strip shadow， air bronchial sign， and the proportion of lesions with irregular shape ≥50%. AUC（95%CI）=0.906（0.817，0.995）.The C index of the training cohort was 0.906， and the C index of the internal verification was 0.892. AUC（95%CI）of the validation cohort 1 （34 cases） =0.889（0.793，0.984）；AUC（95%CI）of the validation cohort 2 （61 cases）=0.876（0.706，1.000）.The calibration curves show that the predicted values of the nomogram are in good agreement with the observed values. ConclusionThe nomogram model based on CT radiomics can predict the outcome of lung lesions in patients with high sensitivity and specificity.According to the changes of CT image characteristics of patients with COVID-19， lung lesions will be improved when the proportion of irregular cable shadow， air bronchogram and irregular lesions is greater than 50%.

The present article was aimed to compare the effectiveness of different induction methods for depression models. Kunming mice were randomly divided into chronic unpredictable mild stress (CUMS) group, corticosterone (CORT) group, and CUMS+CORT (CC) group. The CUMS group received CUMS stimulation for 4 weeks, and the CORT group received subcutaneous injection of 20 mg/kg CORT into the groin every day for 3 weeks. The CC group received both CUMS stimulation and CORT administration. Each group was assigned a control group. After modeling, forced swimming test (FST), tail suspension test (TST) and sucrose preference test (SPT) were used to detect the behavioral changes of mice, and the serum levels of brain-derived neurotrophic factor (BDNF), 5-hydroxytryptamine (5-HT) and CORT were detected with ELISA kits. Attenuated total refraction (ATR) spectra of mouse serum were collected and analyzed. HE staining was used to detect morphological changes in mouse brain tissue. The results showed that the weight of model mice from the CUMS and CC groups decreased significantly. There was no significant change in immobility time of model mice from the three groups in FST and TST, while the glucose preference of model mice from the CUMS and CC groups was significantly reduced (P < 0.05). The serum 5-HT levels of model mice from the CORT and CC groups were significantly reduced, while the serum BDNF and CORT levels of model mice from the CUMS, CORT, and CC groups showed no significant changes. Compared with their respective control groups, the three groups showed no significant difference in the one-dimensional spectrum of serum ATR. The difference spectrum analysis results of the first derivative of the spectrogram showed that the CORT group had the greatest difference from its respective control group, followed by the CUMS group. The structures of hippocampus in the model mice from the three groups were all destroyed. These results suggest that both CORT and CC treatments can successfully construct a depression model, and the CORT model is more effective than the CC model. Therefore, CORT induction can be used to establish a depression model in Kunming mice.
Mice ; Animals ; Depression/etiology* ; Antidepressive Agents/pharmacology* ; Brain-Derived Neurotrophic Factor ; Serotonin