Objective:To establish a rapid and accurate method for the detection of Klebsiella pneumoniae carbapenemase (KPC) carbapenemase gene based on recombinase aided amplification (RAA)-CRISPR-Cas13a (CRISPR-Cas13a) technology. Methods:Twenty-five clinical isolates of carbapenem-resistant Klebsiella pneumoniae (CRKP) and five carbapenem-sensitive Klebsiella pneumoniae (CSKP) strains preserved in 2020-2021 in Beijing Chuiyangliu Hospital were randomly collected, and the total DNA samples of the strains was extracted. RAA primers specific for KPC DNA and CRISPR RNA (crRNA) were designed to establish a rapid and accurate method for the detection of KPC carbapenemase gene based on RAA-CRISPR-Cas13a technology. The method was evaluated by plasmids and clinical sample strains, and the detection was also performed by Quantitative real-time PCR (qPCR) method to compare the detection rate and consistency of the two methods. Results:The RAA-CRISPR-Cas13a method can detect KPC plasmids and samples with a sensitivity of 1 copy/μl, which is higher than that of qPCR (10 1 copies/μl). Among the 30 clinical strains (including 25 CRKP strains and 5 CSKP strains), 23 strains were detected to carry KPC gene by both RAA-CRISPR-Cas13a method and qPCR method, and 7 strains were not detected with KPC gene. The detection rate of KPC gene in the 25 CRKP strains was 92% (23/25). The positive coincidence rate of the two methods was 100% (23/23). Conclusions:This study combined RAA amplification technology with CRISPR-Cas13a technology to establish a rapid and accurate method for detecting KPC carbapenemase gene. The method is useful for accurate screening of KPC carbapenemase-producing strains. It has a wide application prospect in drug resistance monitoring and infection control.

Objective:To know the current situation of kinesiophobia in patients after cardiac surgery under cardiopulmonary bypass, and to clarify its influencing factors, so as to provide reference for developing intervention strategies to improve kinesiophobia level.Methods:This was a cross-sectional study. From February 2022 to September 2022, the patients after cardiac valve surgery under cardiopulmonary bypass in the Second Affiliated Hospital Zhejiang University School of Medicine were investigated by convenience sampling methods. The survey was conducted using the General Information Questionnaire, The Tampa Scale for Kinesiophobia Heart, Exercise Self-Efficacy Scale, Pain Catastrophizing Scale, and Adaptation, Partnership, Growth, Affection and Resolve(APGAR) as research tools, and the influencing factors were analyzed using univariate and binary Logistic regression analysis.Results:A total of 219 patients were included, of which 97 patients (44.3%) had kinesiophobia. The results of binary Logistic regression analysis showed that monthly family income level, first time out of bed after operation, fear of falling, the family APGAR, and pain catastrophizing were significant influencing factors of kinesiophobia in patients after heart valve surgery under cardiopulmonary bypass (all P<0.05). Conclusions:The prevalence of kinesiophobia is high among patients after heart valve surgery under cardiopulmonary bypass. Clinicians should pay attention to patients with low monthly family income level, late first time out of bed after surgery, and fear of falling, as well as strengthen communication with patients and families, focus on the management of acute postoperative pain. In order to reduce or avoid the occurrence of kinesiophobia and enable patients to benefit from early ambulation.

Objective:To investigate the application effect of virtual simulation combined with flipped classroom in experimental teaching of the nursing care of falls in the elderly.Methods:The 497 nursing undergraduates in the class of 2019 in Chongqing Medical University were selected as subjects and were then divided into control group (two classes with 251 students) and intervention group (two classes with 246 students). The students in the control group received traditional experimental teaching, and those in the intervention group received blended experimental teaching with virtual simulation combined with flipped classroom. At the end of the course, the use of virtual simulation platform was analyzed for the students in the intervention group, and a questionnaire survey and theoretical examination were used to compare the effect of experimental teaching between the two groups. SPSS 27.0 was used for the t-test and the chi-square test. Results:The frequency of use of the virtual simulation platform was (2.65±1.38) times per person in the intervention group, with an online learning time of 54.12-147.32 minutes. The questionnaire survey showed that compared with the control group, the intervention group had significantly higher scores of the achievement of teaching objectives and teaching satisfaction ( P<0.05). Compared with the control group after teaching, the intervention group had significantly higher scores of teaching promotion in terms of stimulating learning interest, cultivating self-learning ability, developing clinical thinking ability, improving innovation, and enhancing health education ability ( P<0.05). The intervention group had a significantly higher theoretical examination score than the control group [(79.38±5.09) vs. (77.88±4.97), P<0.05]. Conclusions:In the blended experimental teaching of the nursing care of falls in the elderly, virtual simulation combined with flipped classroom can help students master related knowledge and skills and cultivate their self-learning ability, clinical thinking ability, innovation ability, and health education ability.

【Objective】 To investigate the risk factors of vasovagal reactions(VVR) related to plasma donation, so as to put forward clinical suggestions for early identification and accurate intervention of high-risk groups to ensure the safety of plasma donation. 【Methods】 The demographic characteristics(i.e. gender, age, weight) and records of plasma donors(donation history, pulse before plasma donation, duration of collection, etc.) were collected from July to December 2019 in a region of Sichuan. Based on logistic regression analysis, the correlation between these factors and the risk of VVR was explored. 【Results】 The information of 69 172 donors was collected, and the incidence of VVR was 7.04‰. The risk of VVR was reduced by 99% in the group with plasma collection duration less than 30 minutes compared with the group with plasma collection duration more than 50 minutes(OR, 0.01; 95% CI, 0.00~0.01; P<0.001). The risk of male group was 94 % lower than that of female group(OR, 0.06; 95% CI, 0.04~0.10; P<0.001). Compared with the 45~50 kg group, the risk of weight greater than 80 kg group decreased by 80%(OR, 0.20; 95% CI, 0.09~0.42; P<0.001). The risk of repeated donation group was 34 % lower than that of the first time donation group(OR, 0.66; 95% CI, 0.47~0.91; P<0.001). The risk of VVR in the group with pulse greater than 90 bpm before plasma donation was 2.43 times that in the 60~69 bmp group(OR, 2.43; 95% CI, 1.75~3.36; P<0.001). 【Conclusion】 Duration of plasma collection, gender, weight, frequency of plasma donation, pulse before plasma donation and donor status are independent risk factors for plasma donation-related VVR. Among them, plasma collection duration, gender and weight were the main independent risk factors for plasma donation-related VVR. For donors with plasma collection duration more than 50 minutes, female and low weight, higher risk of VVR was presented and more preventive intervention should be given.

Objective:To investigate the expression and role of asparte-specific cysteine protease (Caspase)-1, inflammasomes key molecule, in hepatitis B virus (HBV)-related diseases.Methods:HBV-related liver disease patients' serum (438 cases) and liver tissue (82 cases) samples were collected from Beijing You'an Hospital affiliated with Capital Medical University. The mRNA expression level of caspase-1 in liver tissue was detected by real-time fluorescence quantitative PCR (qRT-PCR). The protein expression level of Caspase-1 in liver tissue was detected by the immunofluorescence method. The activity of Caspase-1 was detected using the Caspase-1 colorimetric assay kit. The level of Caspase-1 in the serum was detected by an ELISA kit.Results:The results of qRT-PCR showed that the mRNA level of Caspase-1 was downregulated in patients with chronic hepatitis B (CHB), cirrhosis (LC), and hepatocellular carcinoma (HCC), while up-regulated in patients with acute-on-chronic liver failure (ACLF) ( P＜0.01) compared with normal subjects. Immunofluorescence assays showed that Caspase-1 protein levels were elevated in ACLF patients, decreased in HCC and LC patients, and slightly elevated in CHB patients. The activity of Caspase-1 was slightly higher in liver tissue from CHB, LC, and HCC patients than in the normal control group, and there was no statistically significant difference between the groups. Additionally, compared with the control group, Caspase-1 activity was significantly reduced in the ACLF group ( P＜0.01). Serum Caspase-1 levels were significantly lower in patients with CHB, ACLF, LC, and HCC than in normal subjects, and serum Caspase-1 levels were lowest in patients with ACLF ( P＜0.001). Conclusion:Caspase-1, a key molecule of inflammasomes, plays an important role in HBV-related diseases and has significant differences, showing distinct features for ACLF than other HBV-related diseases.

OBJECTIVE：To obs erve the protective effect of protoca techuic aldehyde（PAL）on neurovascular unit （NVU） homeostasis damage in rats after cerebral ischemia-reperfusion injury （CIRI）. METHODS ：SD rats were randomly divided into sham operation group ，model group ，PAL high-dose and low-dose groups （10，20 mg/kg），with 11 rats in each group. Administration groups were given relevant medicine intragastrically. Sham operation group and model group were given the same volume of normal saline intragastrically ，10 mL/kg once a day ，for 5 days. After last administration ，CIRI model was induced by suture method ；the ultrastructural changes of NVU were observed by transmission electron microscope. Western blot assay was used to detect the expression of NUV related proteins （MAP-2，GFAP，AQP-4）in cerebral tissue. Immunofluorescence staining was used to observe the positive expression of above proteins in cerebral cortex. RESULTS ：Compared with sham operation group ， blood-brain barrier （BBB）structure of model group was destroyed severely ，the vascular lumen became narrower ，lateral edema of endothelial cells was severe ，and the thickness of basement membrane varied ；the nuclei of neurons were pyknosis and there was a large area of edema in the surrounding tissues ；the structure of glial cells was seriously damaged ，the cell body was shrunk and organelles were lost ；protein expression （or positive expression ）of MAP- 2 in brain tissue （or cerebral cortex ）were significantly decreased （P＜0.05 or P＜0.01），while protein expression （or positive expression ） of GFAP and AQP- 4 were increased significantly（P＜0.01）. After PAL intervention ，the rats had less BBB damage ，and the morphology of vascular lumen and basement membrane were not completely destroyed ；the damage of neurons was alleviated ，the pyknosis of neurons was decreased ， the chromatin was homogeneous and the heterochromatin was decreased；the damage of glial cell structure was alleviated protein expression of GFAP and AQP- 4（except for low-dose group） in cerebral tissue and positive expression of MAP- 2 and GFAP protein in cerebral cortex were reversed @qq.com significantly （P＜0.05 or P＜0.01）. CONCLUSIONS ：PAL can protect the stability of NVU from damage in CIRI model rats； the mechanism may be related to up-regulating the expression of MAP- 2 protein in cerebral cortex and down-regulating the expression of GFAP and AQP- 4 protein in brain tissue.

ObjectiveTo establish a droplet digital PCR (ddPCR) method for detecting hepatitis B virus (HBV) covalently closed circular DNA (cccDNA). MethodsHBV cccDNA standard substance was constructed, and HBV cccDNA primers and probes were designed based on the structural differences between HBV cccDNA and relaxed circular DNA (rcDNA). HBV plasmid was amplified to obtain HBV cccDNA standard substance, and a ddPCR detection method was established with the standard substance after gradient dilution as the template for HBV cccDNA detection; the limit of detection and repeatability of this method were analyzed. Liver tissue samples were collected from 20 patients who attended Beijing YouAn Hospital, Capital Medical University, from June 2017 to October 2020, all of whom were diagnosed with HBV infection, and DNA of the samples was extracted and digested with plasmid-safe ATP-dependent DNA enzyme to obtain HBV cccDNA template; the ddPCR detection method was evaluated in clinical samples and was compared with the quantitative real-time PCR (qPCR) detection method. The chi-square test was used for comparison of categorical data between the two groups. ResultsThe HBV cccDNA detection method based on ddPCR was established, which accurately detected HBV cccDNA in standard substance after gradient dilution, with a limit of detection of 1 copy/μl, and the coefficients of variation of 1×103, 1×102, and 1×101 copies/μl standard substances were 441%, 3.98%, and 5.09%, respectively. HBV cccDNA was detected in the samples of 20 patients with HBV infection; the ddPCR detection method detected HBV cccDNA in 17 patients, with a positive rate of 85%, while the qPCR detection method detected HBV cccDNA in 11 patients, with a positive rate of 55%, and there was a significant difference between the two methods (χ2=4.286, P=0038). ConclusionThe established ddPCR method for detecting HBV cccDNA has a low limit of detection and good repeatability, which provides an effective tool for further clinical detection.

The imbalance of lipid metabolism is an important factor causing a series of metabolic diseases such as non-alcoholic fatty liver disease (NAFLD) and hyperlipidemia.Liver X receptors is a member of the nuclear receptor superfamily, which maintains cholesterol homeostasis by regulating cholesterol absorption, transport, reverse cholesterol transport, biosynthesis and other functions.It plays an important role in maintaining lipid homeostasis by regulating de novo fat synthesis to maintain the balance of fatty acids in the body.

In view of given that the current development trend of nucleic acid molecular detection technology is gradually shifting from clinical laboratory to field detection, there is an urgent need to establish a new nucleic acid diagnostic tool with high sensitivity, high specificity, great efficiency and convenience portability to meet the needs of clinical point-of-care testing(POCT). The detection method based on clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein (Cas) is a promising new nucleic acid detection method. In this method, the Cas effector protein would recognize highly specific nucleic acid sequences, and it can be used for POCT in combination with a highly sensitive small biosensor. This method can successfully achieves the high-efficiency and convenient detection characteristics while satisfying high sensitivity and high specificity. This article reviews the developments progress in the field of miniaturized analytical sensors related to CRISPR/Cas technology in recent years, and discusses the research prospects and challenges of related POCT detection.

With the continuous development of precision targeting medicine, antiangiogenic drugs have achieved good therapeutic effects in the treatment of advanced cancer, but renal injury and other adverse reactions often occur during the use, which reduce the quality of life of patients. This article reviews the mechanism of renal injury induced by antiangiogenic drugs and the potential relation between renal injury and prognosis.