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 investigate biological markers associated with psychotic symptoms in patients with bipolar disorder(BD)based on electronic medical records of patients,and to develop an interpretable risk prediction model that supports the identification of high-risk individuals and that facilitates decision-making for providing clinical intervention in a timely manner.Methods A total of 2 352 patients diagnosed with BD and admitted to West China Hospital,Sichuan University were enrolled using the electronic medical records system of the hospital.The participants were divided into two subgroups,the bipolar disorder depression(BDD)group and the bipolar disorder mania(BDM)group.The logistic regression algorithm was used to train and validate the prediction model,and interpretability methods were used to analyze the contribution of each feature to individuals and the effect of the features on specific target prediction decisions.Results The logistic regression model demonstrated robust predictive performance across the BD,BDD,and BDM cohorts,with areas under the curve(AUC)of the receiver operating characteristic curves always exceeding 81.6%.The core predictive features included platelet distribution width(PDW),fibrinogen(FIB),platelet large cell ratio(P-LCR),activated partial thromboplastin time(APTT),prothrombin time(PT),and triglyceride(TG).The logistic regression model exhibited strong interpretability and was combined with nomograms for intuitive risk quantification and individualized prediction.Conclusion The logistic regression model enables rapid and simple screening of BD patients with psychotic symptoms.Distinct patterns of changes observed in blood biomarkers of BDD and BDM subgroups enrich the understanding of the underlying pathophysiological mechanisms and highlight the importance of considering subtypes in the intervention and management of patients.

Objective To explore the inhibitory effect of Xinhui tangerine peel polysaccharides on the mouse skin fibroblasts so as to understand the underlying molecular mechanism.Methods We separated and purified the components of tangerine peel polysaccharides from Xinhui tangerine peel.C57BL/6 mouse skin fibroblasts were isolated and cultured for the cellular experimental study.We set up a blank control group(normal culture)and low-,medium-and high-dose experimental groups(50,100 and 200 μg/mL tangerine peel polysaccharides).After 24 hours of treatment,cell survival rate was assessed by CCK-8 assay.The mRNA and protein expression levels of collagen type Ⅰ(Col1a1),collagen type Ⅲ(Col1a3),TGF-β1 and ACTA2 in fibroblasts were examined by RT-qPCR and Western blotting.Smad3 was examined by Western blotting.Results The cell survival rate in the blank control group,the medium-and high-dose experimental groups was 100％,(90.54±6.74)％,and(78.90±4.24)％,respectively.The relative expression level of Col1a1 protein was 1.13±0.15,0.57±0.16,and 0.48±0.05,respectively;the relative expression level of Col3a1 protein was 0.81±0.13,0.49±0.11 and 0.50±0.03;the relative expression level of TGF-β1 protein was 1.11±0.15,0.60±0.13,and 0.33±0.11;the relative expression level of p-Smad3/Smad3 proteins was 0.96±0.05,0.75±0.06 and 0.71±0.03.The mRNA expression level of Col1a1 was 1.01±0.17,0.58±0.11,and 0.52±0.12;the mRNA expression level of Col3a1 was 1.01±0.12,0.56±0.19,and 0.65±0.14;the expression level of ACTA2 mRNA was 1.01±0.13,0.24±0.04,and 0.22±0.07;the mRNA expression level of TGF-β1 was 1.00±0.09,0.50±0.10,and 0.49±0.15.The relative expression levels of p-Smad3/Smad3 proteins were 0.86±0.06,0.66±0.06,0.55±0.13,0.43±0.09,0.35±0.06,and 0.27±0.12,respectively,after time-related treatment with high-dose tangerine peel polysaccharides.The above indicators in medium-and high-dose tangerine peel polysaccharide groups showed statistically significant differences compared to those in the blank control group(P＜0.05).Conclusion Tangerine peel polysaccharides can inhibit the cell proliferation and the synthesis of keloid-related genes on fibroblasts by inhibiting TGF-β1/Smad3 signaling pathway.

Solid-phase extraction(SPE)combined with surface-enhanced Raman spectroscopy(SERS)has emerged as a promising analytical technique for detection and analysis of trace components in complex sample matrices.SPE enriches analytes through selective adsorption and solvent elution,effectively increasing the concentration and signal intensity.SERS enables ultra-sensitive and highly selective molecular analysis through the use of SERS-active substrates engineered to amplify Raman signals.The integration of these two techniques overcomes the limitations of conventional Raman spectroscopy in low-concentration detection field,while significantly improving sample preparation efficiency and analytical accuracy.This review provided a comprehensive overview of the characteristics of three SPE-SERS coupling modes,including two-step,one-step,and online integration.Special emphasis was placed on recent advancements in one-step SPE-SERS approaches based on novel functional adsorbent materials such as graphene,metal-organic frameworks,covalent organic frameworks,and molecularly imprinted polymers.Furthermore,future directions and development prospects of SPE-SERS technology were discussed.

Objective To evaluate the effects of transcatheter aortic valve replacement(TAVR)on left ventricular reverse remodeling(LVRR)and outcomes in patients with mixed aortic valve disease(MAVD)and predominant aortic stenosis(AS).Methods Patients undergoing TAVR at our center between January 2020 and December 2022 were enrolled consecutively.Propensity score matching(PSM)(1∶1 ratio)was used to reduce selection bias.Transthoracic echocardiography(TTE)was used to monitor left ventricular ejection fraction(LVEF)and other structural parameters over time.The study outcome was a composite of cardiovascular death and rehospitalization due to cardiovascular causes.Linear mixed-effects models and logistic regression were utilized for comparing echocardiographic changes across groups and identifying independent risk factors for no-LVRR,respectively.Results After PSM,126 patients were included.MAVD group exhibited larger structural parameters(left ventricular end-systolic/end-diastolic diameter and volume,left ventricular mass index)and a lower left ventricular ejection fraction(LVEF)(all P＜0.05).However,more pronounced improvements in left ventricular structure and hemodynamics were observed during follow-up.Multivariate logistic regression analysis indicated that the left ventricular mass index(LVMI)was an independent predictor of left ventricular reverse remodeling(LVRR)after TAVR,whereas persistent moderate or greater mitral regurgitation(MR)and paravalvular leak(PVL)significantly reduced the incidence of LVRR.During a median follow-up period of 23 months,a total of 31 endpoint events occurred,and there was no statistically significant difference in long-term prognosis between the two groups(Log-rank P=0.330).Conclusions Compared to patients in the AS group,those in the MAVD group exhibited more severe left ventricular remodeling before TAVR.However,more significant LVRR was observed during postoperative follow-up.Additionally,the long-term prognosis was comparable between the two groups.

Objective To explore the inhibitory effect of Xinhui tangerine peel polysaccharides on the mouse skin fibroblasts so as to understand the underlying molecular mechanism.Methods We separated and purified the components of tangerine peel polysaccharides from Xinhui tangerine peel.C57BL/6 mouse skin fibroblasts were isolated and cultured for the cellular experimental study.We set up a blank control group(normal culture)and low-,medium-and high-dose experimental groups(50,100 and 200 μg/mL tangerine peel polysaccharides).After 24 hours of treatment,cell survival rate was assessed by CCK-8 assay.The mRNA and protein expression levels of collagen type Ⅰ(Col1a1),collagen type Ⅲ(Col1a3),TGF-β1 and ACTA2 in fibroblasts were examined by RT-qPCR and Western blotting.Smad3 was examined by Western blotting.Results The cell survival rate in the blank control group,the medium-and high-dose experimental groups was 100％,(90.54±6.74)％,and(78.90±4.24)％,respectively.The relative expression level of Col1a1 protein was 1.13±0.15,0.57±0.16,and 0.48±0.05,respectively;the relative expression level of Col3a1 protein was 0.81±0.13,0.49±0.11 and 0.50±0.03;the relative expression level of TGF-β1 protein was 1.11±0.15,0.60±0.13,and 0.33±0.11;the relative expression level of p-Smad3/Smad3 proteins was 0.96±0.05,0.75±0.06 and 0.71±0.03.The mRNA expression level of Col1a1 was 1.01±0.17,0.58±0.11,and 0.52±0.12;the mRNA expression level of Col3a1 was 1.01±0.12,0.56±0.19,and 0.65±0.14;the expression level of ACTA2 mRNA was 1.01±0.13,0.24±0.04,and 0.22±0.07;the mRNA expression level of TGF-β1 was 1.00±0.09,0.50±0.10,and 0.49±0.15.The relative expression levels of p-Smad3/Smad3 proteins were 0.86±0.06,0.66±0.06,0.55±0.13,0.43±0.09,0.35±0.06,and 0.27±0.12,respectively,after time-related treatment with high-dose tangerine peel polysaccharides.The above indicators in medium-and high-dose tangerine peel polysaccharide groups showed statistically significant differences compared to those in the blank control group(P＜0.05).Conclusion Tangerine peel polysaccharides can inhibit the cell proliferation and the synthesis of keloid-related genes on fibroblasts by inhibiting TGF-β1/Smad3 signaling pathway.

Objective To evaluate the effects of transcatheter aortic valve replacement(TAVR)on left ventricular reverse remodeling(LVRR)and outcomes in patients with mixed aortic valve disease(MAVD)and predominant aortic stenosis(AS).Methods Patients undergoing TAVR at our center between January 2020 and December 2022 were enrolled consecutively.Propensity score matching(PSM)(1∶1 ratio)was used to reduce selection bias.Transthoracic echocardiography(TTE)was used to monitor left ventricular ejection fraction(LVEF)and other structural parameters over time.The study outcome was a composite of cardiovascular death and rehospitalization due to cardiovascular causes.Linear mixed-effects models and logistic regression were utilized for comparing echocardiographic changes across groups and identifying independent risk factors for no-LVRR,respectively.Results After PSM,126 patients were included.MAVD group exhibited larger structural parameters(left ventricular end-systolic/end-diastolic diameter and volume,left ventricular mass index)and a lower left ventricular ejection fraction(LVEF)(all P＜0.05).However,more pronounced improvements in left ventricular structure and hemodynamics were observed during follow-up.Multivariate logistic regression analysis indicated that the left ventricular mass index(LVMI)was an independent predictor of left ventricular reverse remodeling(LVRR)after TAVR,whereas persistent moderate or greater mitral regurgitation(MR)and paravalvular leak(PVL)significantly reduced the incidence of LVRR.During a median follow-up period of 23 months,a total of 31 endpoint events occurred,and there was no statistically significant difference in long-term prognosis between the two groups(Log-rank P=0.330).Conclusions Compared to patients in the AS group,those in the MAVD group exhibited more severe left ventricular remodeling before TAVR.However,more significant LVRR was observed during postoperative follow-up.Additionally,the long-term prognosis was comparable between the two groups.

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.

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.

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.