OBJECTIVE: CRISPR-Cas protects bacteria from exogenous DNA invasion and is associated with bacterial biofilm formation and pathogenicity. METHODS: We analyzed the type I-F CRISPR-Cas system of Legionella pneumophila WX48, including Cas1, Cas2-Cas3, Csy1, Csy2, Csy3, and Cas6f, along with downstream CRISPR arrays. We explored the effects of the CRISPR-Cas system on the in vitro growth, biofilm-forming ability, and pathogenicity of L. pneumophila through constructing gene deletion mutants. RESULTS: The type I-F CRISPR-Cas system did not affect the in vitro growth of wild-type or mutant strains. The biofilm formation and intracellular proliferation of the mutant strains were weaker than those of the wild type owing to the regulation of type IV pili and Dot/Icm type IV secretion systems. In particular, Cas6f deletion strongly inhibited these processes. CONCLUSION The type I-F CRISPR-Cas system may reduce biofilm formation and intracellular proliferation in L. pneumophila.
Legionella pneumophila/pathogenicity* ; CRISPR-Cas Systems ; Biofilms/growth & development* ; Phenotype ; Bacterial Proteins/metabolism* ; Gene Deletion

Objective:To explore the rehabilitation effect of multi-factor intervention based on the Finnish model of prevention of cognitive impairment in the elderly on patients with cognitive impairment after first-episode stroke, and to provide reference for rehabilitation nursing of cognitive impairment after stroke.Methods:The quasi-experiment research scheme was adopted and convenience sampling method was used to select participants with first-episode stroke cognitive impairment hospitalized in the General Hospital of Tianjin Medical University Airport Site. The 50 patients admitted from January to June 2022 were selected as the control group, and 50 patients admitted from July to December 2022 were selected as the intervention group. The control group received routine rehabilitation nursing and health education, and the intervention group received the Finnish model of prevention of cognitive impairment in the elderly on patients before discharge on the basis of the control group. The Mini-Mental State Examination (MMSE) and Health Education Compliance Assessment Scale for Stroke Patients were used to evaluate the changes of overall cognitive function and rehabilitation compliance before intervention, 3 and 6 months after intervention.Results:The final control group included 49 cases, including 35 males and 14 females, aged (64.67 ± 7.47) years old; the intervention group included 50 cases, 32 males and 18 females, aged (66.68 ± 8.75) years old. Before intervention, there were no significant differences in overall cognitive function and compliance of rehabilitation score ( P>0.05). At 3 and 6 months after intervention, the overall cognitive function score, the total score on compliance of rehabilitation, dimension scores of diet compliance, exercise rehabilitation compliance and health behavior compliance of the intervention group were (26.36±2.36) , (125.96 ± 13.80) , (23.30 ± 5.26) , (27.72 ± 4.46) , (43.66 ± 6.80) and (27.26 ± 3.71) , (152.44 ± 9.06) , (30.12 ± 6.42) , (33.32 ± 3.02) , (52.36 ± 4.70) , respectively. They were higher than the control group (24.04 ± 4.50) , (116.67 ± 10.26) , (19.31 ± 3.95) , (25.29 ± 3.45) , (40.59 ± 4.33) and (24.27 ± 4.33) , (138.92 ± 16.71) , (24.20 ± 4.48) , (30.00 ± 5.53) , (47.65 ± 8.03) , and the differences had statistical significance ( t values were -5.31- -2.67, all P<0.05). According to the variance analysis of repeated measurement, intergroup and time factor, the interaction between groups and time had significant impact on general cognitive function score, the total score of rehabilitation compliance, the dimension scores of diet, exercise rehabilitation and health behavior compliance ( Fgroup values were 8.33-18.08, Ftime values were 135.71-944.69, Finteraction values were 5.46-27.30, all P<0.05) . Time factor had significant impact on patient medication adherence score ( Ftime=206.23, P<0.05) . Conclusions:Multi-factor intervention based on the Finnish model of prevention of cognitive impairment in the elderly can improve the overall cognitive function and rehabilitation compliance of patients with cognitive impairment after first-episode stroke.

Endo-beta-N-acetylglucosaminidase (ENGase) is widely distributed in various organisms. The first reported ENGase activity was detected in Diplococcus pneumoniae in 1971. The protein (Endo D) was purified and its peptide sequence was determined in 1974. Three ENGases (Endo F1-F3) were discovered in Flavobacterium meningosepticum from 1982 to 1993. After that, the activity was detected from different species of bacteria, yeast, fungal, plant, mice, human, etc. Multiple ENGases were detected in some species, such as Arabidopsis thaliana and Trichoderma atroviride. The first preliminary crystallographic analysis of ENGase was conducted in 1994. But to date, only a few ENGases structures have been obtained, and the structure of human ENGase is still missing. The currently identified ENGases were distributed in the GH18 or GH85 families in Carbohydrate-Active enZyme (CAZy) database. GH18 ENGase only has hydrolytic activity, but GH85 ENGase has both hydrolytic and transglycosylation activity. Although ENGases of the two families have similar (β/α)8-TIM barrel structures, the active sites are slightly different. ENGase is an effective tool for glycan detection andglycan editing. Biochemically, ENGase can specifically hydrolyze β‑1,4 glycosidic bond between the twoN-acetylglucosamines (GlcNAc) on core pentasaccharide presented on glycopeptides and/or glycoproteins. Different ENGases may have different substrate specificity. The hydrolysis products are oligosaccharide chains and a GlcNAc or glycopeptides or glycoproteins with a GlcNAc. Conditionally, it can use the two products to produce a new glycopeptides or glycoprotein. Although ENGase is a common presentation in cell, its biological function remains unclear. Accumulated evidences demonstrated that ENGase is a none essential gene for living and a key regulator for differentiation. No ENGase gene was detected in the genomes of Saccharomyces cerevisiae and three other yeast species. Its expression was extremely low in lung. As glycoproteins are not produced by prokaryotic cells, a role for nutrition and/or microbial-host interaction was predicted for bacterium produced enzymes. In the embryonic lethality phenotype of the Ngly1-deficient mice can be partially rescued by Engase knockout, suggesting down regulation of Engase might be a solution for stress induced adaptation. Potential impacts of ENGase regulation on health and disease were presented. Rabeprazole, a drug used for stomach pain as a proton inhibitor, was identified as an inhibitor for ENGase. ENGases have been applied in vitro to produce antibodies with a designated glycan. The two step reactions were achieved by a pair of ENGase dominated for hydrolysis of substrate glycoprotein and synthesis of new glycoprotein with a free glycan of designed structure, respectively. In addition, ENGase was also been used in cell surface glycan editing. New application scenarios and new detection methods for glycobiological engineering are quickly opened up by the two functions of ENGase, especially in antibody remodeling and antibody drug conjugates. The discovery, distribution, structure property, enzymatic characteristics and recent researches in topical model organisms of ENGase were reviewed in this paper. Possible biological functions and mechanisms of ENGase, including differentiation, digestion of glycoproteins for nutrition and stress responding were hypothesised. In addition, the role of ENGase in glycan editing and synthetic biology was discussed. We hope this paper may provide insights for ENGase research and lay a solid foundation for applied and translational glycomics.

Ubiquitination, a diverse post-translational modification, is carried out by enzymes including E1-activating enzymes, E2-conjugating enzymes, E3 ligases, and deubiquitinating enzymes (DUBs). Ubiquitin itself possesses 7 lysine residues and N-terminal methionine, allowing for the formation of polyubiquitin chains with different lengths and linkages. These chains exhibit various topologies that can be recognized by proteins containing ubiquitin-binding domain, thereby transmitting distinct cellular signals. To unravel the physiological mechanisms associated with ubiquitin, numerous ubiquitin probes have been developed. This review provides an overview of recent advancements in the field of ubiquitin probes, focusing on activity-based and affinity-based probes. Activity-based probes are designed to covalently bind to DUBs, E1s, or E3s, enabling the identification and characterization of these enzymes. Affinity-based probes, on the other hand, selectively bind to ubiquitin-binding domains, facilitating the identification of proteins that interact with ubiquitin. Moreover, this review comprehensively discusses the synthetic methodologies employed for the acquisition of ubiquitin probes. These includes meticulous discussions on the synthesis of individual monomeric modules, the establishment of isopeptide linkages, as well as the incorporation of reactive functional groups. Additionally, the review explores the emerging area of cell-penetrating ubiquitin probes and highlights their latest applications in living cells. These probes incorporate cell-penetrating peptides to enable their internalization into cells, allowing for direct visualization and manipulation of ubiquitin-modified proteins within their native environment. Overall, this review offers insights into the design, synthesis, and applications of ubiquitin probes, highlighting their significance in elucidating ubiquitin-mediated cellular processes.

Objective To investigate the clinical efficacy of percutaneous closure of foramen ovale guided by transthoracic echocardio-graphy with simply delivery sheath.Methods The clinical data of patients with patent foramen ovale underwent interventional closure and percutaneous closure guided by transthoracic echocardiography with simply delivery sheath in our hospital from January 2020 to December 2022 were analyzed retrospectively,the patients were divided into interventional closure group(40 cases)and simply delivery sheath group(39 cases).The operation time,incidence of surgical complications,and surgical success rates of patients in the two groups were compared.The closure effect were evaluated by ultrasound immediately after surgery.All the patients were followed up for 6 months after surgery to evaluate remission of the symptoms.Results The surgical success rate of simply delivery sheath group(100%)was higher than that of interventional closure group(90.0%),with statistically significant difference(P<0.05).The operation time of simply delivery sheath group was longer than that of interventional closure group,with statistically significant difference(P<0.05).One patient in the interventional closure group had small amount of pericardial effusion during the operation.Two patients had decreased blood pressure and slowed heart rate in simply delivery sheath group,and symptoms disappeared after treatment.There was no significant difference in the incidence of complications between the two groups(P>0.05).After 6-month follow-up,all occluders were in good position and no residual leakage was found.The symptoms of headache or dizziness disappeared in 28 patients in interventional closure group,significantly relieved in 8 patients;the symptoms of headache or dizziness disappeared in 30 patients in simply delivery sheath group,and significantly relieved in 9 patients.Conclusion Percutaneous closure for patent foramen ovale under the guidence of transthoracic echocardiography with simply delivery sheath is safe and feasible with satisfactory efficacy and higher successful rate without radiation hazard.It is worthy of clinical promotion.

Objective To explore the therapeutic mechanism of Liuwei Buqi(LWBQ)Formula for chronic obstructive pulmonary disease(COPD)in rat models.Methods SD rat models of COPD established by cigarette smoking combined with intratracheal lipopolysaccharide(LPS)instillation and hormone injection were treated with LWBQ Formula by gavage with or without intraperitoneal injection of MCC950 for 3 weeks,starting at the 5th week of modeling.After the treatments,the rats were examined for lung pathologies,lung function,total cell count and white blood cell count in bronchoalveolar lavage fluid(BALF),and serum levels of IL-6,TNF-α,IL-18 and NO.The mRNA expressions of NLRP3,ASC,caspase-1,GSDMD-N,IL-1β,and IL-18 in the lung tissue were detected with qRT-PCR.Results Compared with the normal control rats,the COPD rat models had severe lung pathologies and showed significantly decreased lung function,increased total cell and leukocyte subset counts in BALF,and increased serum levels of IL-6,TNF-α,IL-18 and NO and mRNA expressions of pyroptosis-related proteins in the lung tissue.Treatment of the rat models with LWBQ Formula significantly improved lung pathology and lung function,reduced total cell and leukocyte counts in BALF,and decreased serum levels of the inflammatory factors and expressions of pyroptosis-related proteins in the lung tissue.The combined treatment with MCC950 further improved lung pathology and function in spite of a significant difference,but BALF cell counts,serum inflammatory factor levels and pulmonary expressions of pyroptosis-related proteins were all significantly reduced following the treatment.Conclusion LWBQ Formula can delay the progression of COPD in rats possibly by inhibiting lung tissue pyroptosis via regulating the NLRP3/caspase-1/GSDMD pathway to reduce inflammatory response and lung damage.

ObjectiveTo investigate the effect of mucin 1 (MUC1) on the proliferation and apoptosis of nasopharyngeal carcinoma (NPC) and its regulatory mechanism. MethodsThe 60 NPC and paired para-cancer normal tissues were collected from October 2020 to July 2021 in Quanzhou First Hospital. The expression of MUC1 was measured by real-time quantitative PCR (qPCR) in the patients with PNC. The 5-8F and HNE1 cells were transfected with siRNA control (si-control) or siRNA targeting MUC1 (si-MUC1). Cell proliferation was analyzed by cell counting kit-8 and colony formation assay, and apoptosis was analyzed by flow cytometry analysis in the 5-8F and HNE1 cells. The qPCR and ELISA were executed to analyze the levels of TNF-α and IL-6. Western blot was performed to measure the expression of MUC1, NF-кB and apoptosis-related proteins (Bax and Bcl-2). ResultsThe expression of MUC1 was up-regulated in the NPC tissues, and NPC patients with the high MUC1 expression were inclined to EBV infection, growth and metastasis of NPC. Loss of MUC1 restrained malignant features, including the proliferation and apoptosis, downregulated the expression of p-IкB、p-P65 and Bcl-2 and upregulated the expression of Bax in the NPC cells. ConclusionDownregulation of MUC1 restrained biological characteristics of malignancy, including cell proliferation and apoptosis, by inactivating NF-κB signaling pathway in NPC.

[Objective] To investigate the role of miR-199a-3p on mouse skin scar fibroblasts and the potential target of miR-199a-3p. [Methods] A mouse skin keloid model was established. The mRNA levels of miR-199a-3p, Smad1 and keloid related genes in keloid tissues and normal skin tissues were detected by Real-time quantitative PCR. C57BL/6 mouse skin fibroblasts were isolated and cultured for the cellular experimental study. miR-199a-3p mimic and Smad1 siRNA matter were transiently transfected into mouse skin fibroblasts by liposome reagent. the interaction between miR-199a-3p and the 3′-UTR of Smad1 was confirmed by the dual luciferase reporter assay. The expressions of Smad1 and keloid-related genes at mRNA and protein levels after transfection of miR-199a-3p mimic were determined. The expressions of Smad1 and keloid-related genes at protein level after transfection of miR-199a-3p mimic and Smad1 siRNA were determined by Western blot assay. [Results] Compared with normal skin tissues, the expressions of Smad1 (t=-4.403, P=0.010) and keloid related genes, Col1a1(t=-3.334, P=0.016), Col3a1(t=-5.927, P=0.001) and ACTA2(t=-3.673, P=0.010), were significantly increased in keloid tissues, while miR-199a-3p (t=7.059, P<0.001) expression was significantly decreased. Over-expression of miR-199a-3p could significantly decrease the expressions of keloid-related genes, Col1a1 (t=5.514, P=0.005), Col3a1 (t=5.132, P=0.014) and ACTA2 (t=4.136, P=0.026), in mouse skin fibroblasts. Moreover, the dual luciferase reporter assay revealed that miR-199a-3p could interact with the 3′-UTR of Smad1. miR-199a-3p was observed to inhibit Smad1 at mRNA expression level (t=3.556, P=0.024), and at the post-transcriptional level (t=3.781, P=0.019). Meanwhile, miR-199a-3p mimic, in parallel to Smad1 siRNA, decreased the expressions of keloid-related genes, Col1a1 (F=18.804; P=0.003, 0.022), Col3a1 (F=33.212; P=0.001, 0.001) and α-SMA (F=10.181; P=0.020, 0.028), and decreased the proliferation of skin fibroblasts (F=18.622; P=<0.001, <0.001). [Conclusion] miR-199a-3p inhibits the formation of keloid by targeting Smad1.

Objective To explore the therapeutic mechanism of Liuwei Buqi(LWBQ)Formula for chronic obstructive pulmonary disease(COPD)in rat models.Methods SD rat models of COPD established by cigarette smoking combined with intratracheal lipopolysaccharide(LPS)instillation and hormone injection were treated with LWBQ Formula by gavage with or without intraperitoneal injection of MCC950 for 3 weeks,starting at the 5th week of modeling.After the treatments,the rats were examined for lung pathologies,lung function,total cell count and white blood cell count in bronchoalveolar lavage fluid(BALF),and serum levels of IL-6,TNF-α,IL-18 and NO.The mRNA expressions of NLRP3,ASC,caspase-1,GSDMD-N,IL-1β,and IL-18 in the lung tissue were detected with qRT-PCR.Results Compared with the normal control rats,the COPD rat models had severe lung pathologies and showed significantly decreased lung function,increased total cell and leukocyte subset counts in BALF,and increased serum levels of IL-6,TNF-α,IL-18 and NO and mRNA expressions of pyroptosis-related proteins in the lung tissue.Treatment of the rat models with LWBQ Formula significantly improved lung pathology and lung function,reduced total cell and leukocyte counts in BALF,and decreased serum levels of the inflammatory factors and expressions of pyroptosis-related proteins in the lung tissue.The combined treatment with MCC950 further improved lung pathology and function in spite of a significant difference,but BALF cell counts,serum inflammatory factor levels and pulmonary expressions of pyroptosis-related proteins were all significantly reduced following the treatment.Conclusion LWBQ Formula can delay the progression of COPD in rats possibly by inhibiting lung tissue pyroptosis via regulating the NLRP3/caspase-1/GSDMD pathway to reduce inflammatory response and lung damage.

Objective: To establish a predictive model for survival benefit of patients with intrahepatic cholangiocarcinoma (ICC) who received adjuvant chemotherapy after radical resection. Methods: The clinical and pathological data of 249 patients with ICC who underwent radical resection and adjuvant chemotherapy at 8 hospitals in China from January 2010 to December 2018 were retrospectively collected. There were 121 males and 128 females,with 88 cases>60 years old and 161 cases≤60 years old. Feature selection was performed by univariate and multivariate Cox regression analysis. Overall survival time and survival status were used as outcome indicators,then target clinical features were selected. Patients were stratified into high-risk group and low-risk group,survival differences between the two groups were analyzed. Using the selected clinical features, the traditional CoxPH model and deep learning DeepSurv survival prediction model were constructed, and the performance of the models were evaluated according to concordance index(C-index). Results: Portal vein invasion, carcinoembryonic antigen>5 μg/L,abnormal lymphocyte count, low grade tumor pathological differentiation and positive lymph nodes>0 were independent adverse prognostic factors for overall survival in 249 patients with adjuvant chemotherapy after radical resection (all P<0.05). The survival benefit of adjuvant chemotherapy in the high-risk group was significantly lower than that in the low-risk group (P<0.05). Using the above five features, the traditional CoxPH model and the deep learning DeepSurv survival prediction model were constructed. The C-index values of the training set were 0.687 and 0.770, and the C-index values of the test set were 0.606 and 0.763,respectively. Conclusion: Compared with the traditional Cox model, the DeepSurv model can more accurately predict the survival probability of patients with ICC undergoing adjuvant chemotherapy at a certain time point, and more accurately judge the survival benefit of adjuvant chemotherapy.