To efficiently produce non-specific nuclease (NU) of Serratia marcescens through recombinant overexpression approach and to characterize the purified NU. The nuclease gene was amplified from the genomic DNA of Serratia marcescens by PCR and fused into vector pMAL-c4X with maltose binding protein (MBP) tag. The recombinant vector verified by DNA sequencing was transformed into Escherichia coli BL21. The expressed MBP-NU was purified through the amylose resin and its catalytic characters were analyzed. The results showed the NU gene had 97% identities with the reported S. marcescens nuclease gene and intracellularly expressed in E. coli BL21. The optimal expression conditions were 37 degrees C, 0.75 mmol/L IPTG with 1.5 h induction. The purified MBP-NU exhibited non-specific nuclease activity, able to degrade various nucleic acids, including RNA, single-stranded DNA and double-stranded DNA that was circular or linear. Its optimal temperature was 37 degrees C and optimal pH 8.0. From 1 L culture broth 10.8 mg NU could be purified with a specific activity of 1.11x10(6) U/mg. The catalytic activity of NU was not inhibited by reagents such as EDTA (0.5 mmol/L), PMSF (1 mmol/L) and KCl (150 mmol/L) commonly used in protein purification.
Base Sequence ; Endodeoxyribonucleases ; biosynthesis ; genetics ; Endoribonucleases ; biosynthesis ; genetics ; Escherichia coli ; genetics ; metabolism ; Maltose-Binding Proteins ; genetics ; Molecular Sequence Data ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; isolation & purification ; Serratia marcescens ; enzymology

Diabetic nephropathy is a microvascular complication in the advanced stage of diabetes. About 20%-40% of patients with diabetes will progress to diabetic nephropathy. And worldwide, diabetic nephropathy has become the leading cause of end-stage renal disease. Animal model is a useful tool to study the pathogenesis and treatment of diabetic nephropathy. Currently, the commonly used diabetic nephropathy models all simulate partial characteristics of human diabetic nephropathy in different degrees of pathophysiology. However, the research on diabetic nephropathy has not achieved considerable progress. The main obstacle is that there is no effective animal model that can fully simulate all the characteristics of human diabetic nephropathy. In this paper, the animal models of diabetic nephropathy were reviewed from the aspects of modeling mechanism, pathophysiology, their advantages and disadvantages.

Objective:To systematically evaluate the application effect of somatosensory interactive games in patients with chronic obstructive pulmonary disease (COPD) in order to provide a basis for clinical application.Methods:Randomized controlled trials and quasi-experimental studies on the application of somatosensory interactive games in patients with COPD were retrieved from PubMed, Embase, Cochrane Library, CINAHL, Chinese Biomedical Literature Database, Wanfang, China Knowledge Network and VIP. The retrieval time limit is from the establishment of the database to October 2022. RevMan5.2 software was used for Meta analysis.Results:Ten articles involving 611 patients were included. The results of Meta-analysis showed that the somatosensory interactive game group was superior to the conventional training group in improving FEV 1/FVC% ( WMD=6.83, 95% CI 3.71-9.95, Z=4.29, P<0.01), 6-minute walking distance (6MWD) ( WMD=13.36, 95% CI 0.50-26.23, Z=2.04, P<0.05), Hospital Anxiety and Depression Scale ( WMD=-1.64, 95% CI -2.31--0.97, Z=4.78, P<0.01), COPD Assessment Test score ( WMD=-2.95, 95%CI -4.08--1.82, Z=5.13, P<0.01) in COPD patients. However, there was no significant difference in FEV1 % ( WMD=2.91, 95% CI -1.61-7.43, P=0.210) and dyspnea ( SMD=0.63,95% CI -0.24-1.49, P=0.150) between the two groups. Conclusions:Compared with conventional training, somatosensory interactive game training can effectively improve lung function and quality of life in patients with COPD, relieve anxiety and depression. Due to the limited quantity and quality of the included literature, the reliability of the conclusions still needs to be verified by more high-quality studies.

Objective:To understand the awareness and influencing factors of core information on tuberculosis prevention and control in the elderly population in China.Methods:The study included all participants aged ≥60 from the "13 th Five-Year" National Tuberculosis Control Plan end-term assessment in 2020, with 13 706 valid questionnaires obtained. Multivariate logistic regression was used to analyze the influencing factors of the awareness rate of core information on tuberculosis prevention and control in the elderly. Results:The total awareness rate of core information on tuberculosis prevention and control in the elderly aged ≥60 was 78.4%, with the highest for "suspicious symptoms of pulmonary tuberculosis" (85.4%) and the lowest for "whether pulmonary tuberculosis can be cured" (65.3%). The complete awareness rate of core information on tuberculosis prevention and control in the elderly was 41.3%, and the proportion of those who received tuberculosis health education is 67.6%. Multivariate logistic regression analysis results showed that factors associated with low awareness of core information included females ( OR=0.93, 95% CI: 0.86-1.00), ages 70- ( OR=0.91, 95% CI: 0.84-0.98) and ≥80 ( OR=0.77, 95% CI: 0.68-0.87) and minority ethnicity ( OR=0.85, 95% CI: 0.74-0.99). Factors associated with high awareness of core information included educational levels of junior high school ( OR=1.46, 95% CI: 1.34-1.58), high school ( OR=1.62, 95% CI: 1.45-1.81), junior college ( OR=1.37, 95% CI: 1.11-1.68), and an undergraduate degree or higher ( OR=1.52, 95% CI: 1.09-2.11), and receiving tuberculosis health education ( OR=2.13, 95% CI: 1.97-2.27). Conclusions:In 2020, the awareness rate of core information on tuberculosis prevention and control in Chinese older adults aged ≥60 was lower than the national planning target. Therefore, there should be an increased focus on health education about tuberculosis for elderly females, those aged ≥70, ethnic minorities, and those with lower education levels.

Objective To investigate the multi spiral computed tomography(MSCT)characteristics and biological behaviors of advanced gastrointestinal signet ring cell carcinoma(SRCC),so as to provide accurate preoperative type,stage and personalized choice of treatment strategy in clinical practice.Methods The clinical manifestations,five tumor markers and MSCT imaging data of 26 cases(group A)with advanced gastrointestinal SRCC confirmed by surgical or endoscopic biopsy and pathological immunohistochemistry were analyzed retrospectively,and 44 cases(group B)of advanced non-signet ring cell carcinoma(NSRCC)during the same period were randomly selected as the control group.The clinical manifestations,five tumor markers and MSCT imaging features of groups A and B were analyzed.Results There were no significant differences in gender,tumor location,tumor thickness(T)and length(L),and five tumor markers between groups A and B(P＞0.05).There were significant differences in age,main symptoma,tumor thickness-to-length ratio(TLR),angle between cancerous edge and normal tissue(CNA)(P＜0.05).However,age of group A and group B[group A≤50 years old(12/26,46％),group B＞50 years old(42/44,95％)],main symptom(x2=19.085,P＜0.05),tumor TLR(Z=-2.044,P＜0.05)and CNA(x2=14.776,P＜0.05)were significantly different(P＜0.05).Conclusion SRCC affects younger patients and is more likely to originate from the middle and lower parts of the stomach and rectum,with lower TLR,obtuse angle of CNA,and"caterpillar-like"characteristics of colorectal SRCC.

Tumor microenvironment(TME)is a complex cellular environment where tumor cells reside,along with various types of cells and extracellular components surrounding the tumor cells.Immune cells are key components of TME,including tumor-associated macrophages(TAMs),myeloid-derived suppressor cells(MDSCs),lymphocytes,regulatory T cells(Tregs),natural killer cells(NK cells),dendritic cells(DCs),and many others.It is worth noting that drug resistance is currently a major factor limiting the efficacy of cancer treatment methods such as chemotherapy,radiotherapy,targeted therapy,and immunotherapy,and a leading cause of treatment failure.Research has found that the development of drug resistance in tumor cells is the result of interactions between tumor cells and TME.Consequently,overcoming drug resistance in tumors caused by TME is considered a significant challenge in cancer treatment.In recent years,with in-depth research into immune cells within TME,significant progress has been made in understanding the specific mechanisms by which immune cells regulate drug resistance in tumor cells.Furthermore,therapeutic strategies that target these immune cells,signaling pathways,or cytokines have been shown to effectively combat tumor drug resistance and enhance the therapeutic outcomes of cancer treatment.This article reviews the research advancements regarding the roles of TAMs,MDSCs,Tregs,and NK cells in tumor drug resistance within TME and discusses the development of targeting strategies to overcome this resistance.Additionally,we explore the relationship of tumor-associated neutrophils(TANs)and B regulatory cells(Bregs)with tumor drug resistance.It is hoped that this review will offer insights and serve as reference for reducing tumor drug resistance and improving the efficacy of anti-tumor therapies.

Chest trauma is one of the most common injuries. Venous thromboembolism (VTE) as a common complication of chest trauma seriously affects the quality of patients′ life and even leads to death. Although there are some consensus and guidelines on the prevention and treatment of VTE at home and abroad, the current literatures lack specificity considering the diagnosis, treatment and prevention of VTE in patients with chest trauma have their own characteristics, especially for those with blunt trauma. Accordingly, China Chest Injury Research Society and editorial board of Chinese Journal of Traumatology organized relevant domestic experts to jointly formulate the Chinese expert consensus on the diagnosis, treatment and prevention of chest trauma venous thromboembolism associated with chest trauma (2022 version). This consensus provides expert recommendations of different levels as academic guidance in terms of the characteristics, clinical manifestations, risk assessment, diagnosis, treatment, and prevention of chest trauma-related VTE, so as to offer a reference for clinical application.

Cadinanes are a class of bicyclic sesquiterpenes with complex stereochemistry and broad pharmacological activities, such as antibacterial, anti-inflammatory, and hypoglycemic activities. To date, structurally diverse and bioactive cadinane sesquiterpenes have been isolated and identified from a variety of plants and microorganisms. Moreover, deeper understandings on cadinane sesquiterpene synthases have been made. This article categorized the 124 new cadinanes which were published in the literatures in the past four years (2017-2020) into five structural types, and presented their pharmacological activities. We also illustrated the elucidation of the biosynthetic pathways for typical cadinanes, summarized the research progress on cadinane sesquiterpene synthases. Finally, current challenges and future prospects were proposed and discussed.
Anti-Inflammatory Agents ; Polycyclic Sesquiterpenes ; Sesquiterpenes