This study was aimed at investigating the effectiveness of various host nucleic acid removal and non-specific amplifica-tion techniques in animal tissue samples,to increase the accuracy of pathogen identification in tissue samples.Simulated samples were prepared with a mixture of mouse lung tissue homogenates and Klebsiella pneumoniae fluids,and processed with six host nucleic acid removal kits and three non-specific amplification techniques.The effectiveness of each method in removing host DNA and enriching nucleic acids of pathogenic microorganisms was evaluated through real-time fluorescence quantitative PCR and high-throughput se-quencing.For host nucleic acid removal techniques,the method of selective cleavage and quantitative degradation of host DNA(Com-plete5 kit)effectively decreased the host nucleic acid content in tissue samples and increased the relative abundance of pathogen nucleic acids.In contrast,the magnetic bead method for host DNA removal(Next microbiome DNA enrichment Kit kit)was less effec-tive.At lower pathogen concentrations(77 CFU/mL),the Vazyme kit was more effective than the other kits in removing host nucleic acids.Non-specific amplification techniques(MALBAC whole genome amplification,MDA isothermal amplification,and random primer amplification)were not applicable to tissue samples and were not effective in increasing the relative abundance of pathogen nucleic acids.Selective lysis and quantitative degradation of host DNA were suitable for processing tissue samples with high host back-ground and low pathogenic microorganism levels,whereas non-specific amplification methods were not applicable to tissue samples for pre-processing of macro-genome high-throughput sequencing.

Objective:To evaluate the incidence, clinical features, factors affecting initial diagnosis, efficacy, and safety of therapy and prognosis of small intestinal Dieulafoy lesions (DL).Methods:Clinical data including clinical background, diagnosis, and treatment details of patients who were admitted to the Department of Gastroenterology, Air Force Medical Center, for suspected small bowel bleeding, diagnosed as having small bowel DL and treated with balloon-assisted enteroscopy (BAE) were retrospectively analyzed from November 2017 to March 2024.Results:Among 800 patients, 30 cases (3.75%, 30/800, 17 males and 13 females) were diagnosed as having small intestine DL with the mean age of 60.90 years. Clinical symptoms included melena (56.67%, 17/30), hematochezia (43.33%, 13/30), and hemodynamic instability (30.00%, 9/30). Active bleeding occurred in 23 (76.67%) patients. Comorbidities existed in 70.00% (21/30) and 33.33% (10/30) used long-term antithrombotic agents. Diagnosis was confirmed after a single BAE in 63.33% (19/30) and after multiple BAEs (mean 1.6 procedures) in 36.67% (11/30). Lesions were predominantly located at jejunal. All patients achieved successful treatment with a single BAE procedure. The median follow-up period was 12.25 months (range: 5.25-23.00 months). Five cases (16.67%) experienced recurrent bleeding, with one case transfered to surgical intervention. Two cases (6.67%) reported post-operative symptoms of dizziness and fatigue, which resolved after symptomatic management. Multivariate analysis showed that long-term oral anticoagulant therapy ( OR=0.06, 95% CI: 0.01-0.73) was an independent predictor of single-session diagnosis. Conclusion:Small intestinal DL is rare and challenging to diagnose. Antithrombotic therapy may facilitate the diagnosis of DL at the first BAE. Jejunal localization is common, and combined endoscopic therapy (including clipping) is effective and safe.

This study was aimed at investigating the effectiveness of various host nucleic acid removal and non-specific amplifica-tion techniques in animal tissue samples,to increase the accuracy of pathogen identification in tissue samples.Simulated samples were prepared with a mixture of mouse lung tissue homogenates and Klebsiella pneumoniae fluids,and processed with six host nucleic acid removal kits and three non-specific amplification techniques.The effectiveness of each method in removing host DNA and enriching nucleic acids of pathogenic microorganisms was evaluated through real-time fluorescence quantitative PCR and high-throughput se-quencing.For host nucleic acid removal techniques,the method of selective cleavage and quantitative degradation of host DNA(Com-plete5 kit)effectively decreased the host nucleic acid content in tissue samples and increased the relative abundance of pathogen nucleic acids.In contrast,the magnetic bead method for host DNA removal(Next microbiome DNA enrichment Kit kit)was less effec-tive.At lower pathogen concentrations(77 CFU/mL),the Vazyme kit was more effective than the other kits in removing host nucleic acids.Non-specific amplification techniques(MALBAC whole genome amplification,MDA isothermal amplification,and random primer amplification)were not applicable to tissue samples and were not effective in increasing the relative abundance of pathogen nucleic acids.Selective lysis and quantitative degradation of host DNA were suitable for processing tissue samples with high host back-ground and low pathogenic microorganism levels,whereas non-specific amplification methods were not applicable to tissue samples for pre-processing of macro-genome high-throughput sequencing.

Objective:To evaluate the incidence, clinical features, factors affecting initial diagnosis, efficacy, and safety of therapy and prognosis of small intestinal Dieulafoy lesions (DL).Methods:Clinical data including clinical background, diagnosis, and treatment details of patients who were admitted to the Department of Gastroenterology, Air Force Medical Center, for suspected small bowel bleeding, diagnosed as having small bowel DL and treated with balloon-assisted enteroscopy (BAE) were retrospectively analyzed from November 2017 to March 2024.Results:Among 800 patients, 30 cases (3.75%, 30/800, 17 males and 13 females) were diagnosed as having small intestine DL with the mean age of 60.90 years. Clinical symptoms included melena (56.67%, 17/30), hematochezia (43.33%, 13/30), and hemodynamic instability (30.00%, 9/30). Active bleeding occurred in 23 (76.67%) patients. Comorbidities existed in 70.00% (21/30) and 33.33% (10/30) used long-term antithrombotic agents. Diagnosis was confirmed after a single BAE in 63.33% (19/30) and after multiple BAEs (mean 1.6 procedures) in 36.67% (11/30). Lesions were predominantly located at jejunal. All patients achieved successful treatment with a single BAE procedure. The median follow-up period was 12.25 months (range: 5.25-23.00 months). Five cases (16.67%) experienced recurrent bleeding, with one case transfered to surgical intervention. Two cases (6.67%) reported post-operative symptoms of dizziness and fatigue, which resolved after symptomatic management. Multivariate analysis showed that long-term oral anticoagulant therapy ( OR=0.06, 95% CI: 0.01-0.73) was an independent predictor of single-session diagnosis. Conclusion:Small intestinal DL is rare and challenging to diagnose. Antithrombotic therapy may facilitate the diagnosis of DL at the first BAE. Jejunal localization is common, and combined endoscopic therapy (including clipping) is effective and safe.

Standards are the technical support for economic activities and social development. The construction and standardization of the pathogenic microorganism preservation standard system is an important technical foundation for the high-quality development of preservation work. Establishing a pathogenic microorganism resource standard system is also important to the national biosafety standards. Through the standardization of pathogenic microbial resource preservation, we can ensure the effective management and sustainable utilization of pathogenic microbial resources, promote the transformation of resources, and serve as an important new element of new productivity to assist the innovative development of biosafety science and technology. This article elaborates and analyzes the establishment background, construction framework, standardization process, and application effects of the standard system for preserving pathogenic microbial resources, providing stronger support for further improving the standard system and promoting the standardization of pathogenic microbial resource preservation.

OBJECTIVE To investigate the in vitro inhibitory mechanism of berberine on the proliferation of tumor stem cells and evaluate its in vivo safety. METHODS Flow cytometry was used to select tumor stem cells from mouse skin melanoma B16F10 cells； CD44， CD133， Nanog homologous box protein （NANOG） and octamer-binding transcription factor 4 （OCT4） were used as indicators to characterize tumor stem cells. Tumor stem cells were divided into control group， all-trans retinoic acid （ATRA） group， and berberine group， and the CCK-8 method was used to detect the effects of berberine on the viability of tumor stem cells； flow cytometry was adopted to detect cell apoptotic rate， the proportion of CD44+/CD133+ and the positive cell rate of sex determining region Y box protein 2 （SOX2）； the morphological changes of tumor balls were recorded after treatment with berberine； the morphology of cell pyroptosis in each group was recorded， and the release rate of lactate dehydrogenase （LDH） was detected； Western blot assay was adopted to detect the expressions of pyroptosis-related protein gasdermin E （GSDME）， GSDME- N， caspase-3 and cleaved caspase-3. Preliminary evaluation of in vivo safety of berberine was conducted by using zebrafish embryo toxicity experiments. RESULTS Compared with B16F10 cells， the proportion of CD44+/CD133+ cells in tumor stem cells and the fluorescence intensity of NANOG and OCT4 were significantly increased （P＜0.000 1）. The half-inhibitory concentration of berberine to tumor stem cells was 50.98 μmol/L. Compared with the control group， the apoptotic rate of cells in the berberine group was significantly increased， while the proportion of CD44+/CD133+ cells and the rate of SOX2 positive cells were reduced significantly （P＜0.000 1）； tumor stem cell spheroids were atrophied， with partial cell death. After treatment with berberine， tumor stem cells exhibited swelling in their outermost layer， the release rate of LDH of cells was significantly increased and the release rate of LDH increased with increasing dose； the protein expressions of GSDME-N and cleaved-caspase-3 of cells in berberine 20， 40 μmol/L groups were significantly increased， and the protein expressions of GSDME and caspase-3 were significantly reduced （except for berberine 20 μmol/L group， P＜0.05）. The embryonic development of zebrafish treated with berberine was almost unaffected， and the survival rate of embryo reached 100%， with no obvious abnormalities observed. CONCLUSIONS Berberine has good activity against the proliferation of tumor stem cells， and its mechanism of action may be related to activating GSDME and promoting cell pyroptosis； berberine has good in vivo safety.

Objective:To construct and test the reliability and validity of an assessment scale for self-management of patients with dry eye, so as to help patients establish dry eye related health behaviors.Methods:Based on the knowledge attitude and practice theory, the initial scale was constructed on the basis of literature review and qualitative interview, and revised through Delphi expert consultation and expert argumentation. After the preliminary investigation, 211 dry eye patients treated in the dry eye nursing outpatient department of Beijing Tongren Hospital from August 2023 to January 2024 were selected by convenience sampling method for questionnaire investigation to test the reliability and validity of the scale.Results:Among 211 dry eye patients, there were 58 males and 153 females, aged (39.31 ± 12.81) years old. The scale of self-management of patients with dry eye included 27 items in 3 dimensions: knowledge, attitude and behavior. The authority coefficient of the two rounds of expert consultation was 0.86, and the Kendall coordination index increased from 0.175 to 0.223 (both P < 0.01). The cumulative variance contribution rates of the three dimensions were 41.843%, 54.219% and 44.273%, respectively. The Cronbach α coefficient of the scale was 0.787, and the Spearman-Brown coefficient was 0.641. Conclusions:The scale of self-management of patients with dry eye has good reliability and validity and can be used in the assessment of dry eye patients to provide a reference basis for targeted guidance and intervention.

Objective:To construct a questionnaire on the knowledge, attitude and practice (KAP) of community general practitioners for colorectal cancer screening.Methods:From September 2023 to June 2024, an initial version of questionnaire on knowledge, attitude and practice (KAP) of community general practitioners for colorectal cancer screening was formed based on existing guidelines and related research results; then two-round Delphi experti consultation was held to finalize the initial questionnaire.Results:Twenty one experts were invited for Delphi consultation, including 14 general practitioners and 7 gastroenterologists; 7 from community health service centers and 14 from public tertiary hospitals. The enthusiasm of experts in the first round and second round consultations was 100.0% and 90.5%; the consistency of experts was 4.03-4.75 and 4.39-4.93; the coordination of experts was 0.09-0.22 and 0.03-0.12, respectively. The Kendall coordination coefficients were 0.154 and 0.390 respectively ( P<0.001), indicating that there was significant consistency in expert opinions and the results of the letter inquiry were highly reliable. The final version of the KAP questionnaire included 28 items in three dimensions: knowledge, attitude, and behavior. Among them, knowledge items K1-K9 included the determination of risk population, risk factors, screening methods, screening intervals, and other contents; attitude items A1-A12 included attitudes towards factors of patients, doctors and government that affect screening, and attitudes towards the necessity of screening; behavior items P1-P7 included active screening behaviors such as patient assessment and advices for active screening. Conclusion:This study has preliminarily constructed a questionnaire on knowledge, belief and behavior of general practitioners for colorectal cancer screening.

RNAs are involved in the crucial processes of disease progression and have emerged as powerful therapeutic targets and diagnostic biomarkers. However, efficient delivery of therapeutic RNA to the targeted location and precise detection of RNA markers remains challenging. Recently, more and more attention has been paid to applying nucleic acid nanoassemblies in diagnosing and treating. Due to the flexibility and deformability of nucleic acids, the nanoassemblies could be fabricated with different shapes and structures. With hybridization, nucleic acid nanoassemblies, including DNA and RNA nanostructures, can be applied to enhance RNA therapeutics and diagnosis. This review briefly introduces the construction and properties of different nucleic acid nanoassemblies and their applications for RNA therapy and diagnosis and makes further prospects for their development.

Technical requirements for evaluation of national standard strains of pathogenic microorganisms (WS/T 812—2022)have been implemented since May 1, 2023. This is one of the concrete and important measures to implement Biosafety Law of the People′s Republic of China, the National Health Commission of the pathogenic microorganisms of collection organization of the " 14th Five-Year" development plan and to improve the standard system of pathogenic resource preservation and biosafety in China. For the first time, this standard specifies a definition, four evaluation principles, five types of use, and three evaluation indicators of national standard strains of pathogenic microorganisms, and standardizing the evaluation technical procedures and certificate. After the implementation of the standard, it will strongly support the national needs for the evaluation and application of pathogenic microorganism standard strains, such as infectious disease prevention and control, food safety testing, and biometrics specification, gradually reduce the long-term dependence on foreign standard strains and other " bottleneck" problems, help national biosecurity and high level science and technology self-reliance while promoting the innovation and high-level development of biotechnology.