The Gram-negative bacteria Escherichia coli Nissle 1917(EcN)is a probiotic that has been widely applied in clinical practice.With its notable tolerance,safety,and antimicrobial proper-ties,EcN demonstrates the capacity to colonize the intestine and establish a symbiotic relationship with the host,thereby balancing the intestinal microbiota.Extensive studies have elucidated the mechanisms through which EcN regulates the host's innate immune response enhancing the host's ability to combat pathogenic invasions.On one hand,EcN strengthens the integrity of the intestinal mucosal barrier by upregulating the expression of tight junction proteins.On the other hand,EcN's diverse array of secreted,and released components,including lipopolysaccharides,K5 capsule,fla-gellum proteins,and fimbria,play roles in modulating the host's innate immune response.These components interact with host cell receptors and modulate the activities of immune cells and cyto-kines production.By consolidating the current understanding of EcN's probiotic properties,this ar-ticle provides a comprehensive overview of the intricate mechanisms underlying EcN-mediated reg-ulation of the host's innate immune response.Such insights offer theoretical support for leveraging EcN's advantages and improving immune function and overall health maintenance in the host.

Objective:To analyze the carriage status, subtype distribution and flanking gene sequence characteristics of oxacillinases (OXA enzyme) in 241 clinical strains of Pseudomonas aeruginosa, and assess their roles in the drug resistance of Pseudomonas aeruginosa and ability to horizontally transfer across species. Methods:Clinical P. aeruginosa isolates were collected from four hospitals in Sanya, Tangshan, Zhangjiakou, and Beijing. The prevalence of oxacillinases and their flanking gene sequences was analyzed by whole-genome sequencing (NGS) and bioinformatic approaches. Results:A total of 241 isolates of P. aeruginosa were gathered, and 35 blaOXA subtypes were identified through screening of 252 blaOXA genes. These genes were classified into three subfamilies: blaOXA-50-like (241, 95.6%), blaOXA-1-like (9, 3.6%) and blaOXA-10-like (2, 0.8%). Among these, 11 subtypes (11, 31.4%) were novel blaOXA subtypes. Nine of these belonged to the blaOXA-50-like subfamily and were designated as blaOXA-1244, blaOXA-1245, blaOXA-1246, blaOXA-1250, blaOXA-1252, blaOXA-1253, blaOXA-1254, blaOXA-1255, and blaOXA-1256. The remaining two belonged to the blaOXA-10-like subfamily and were named blaOXA-1247 and blaOXA-1248. Compared to the amino acid sequence of OXA-10, the newly identified subtype OXA-1247 exhibited a mutation at position 117, where a valine was replaced by a leucine. This change was thought to improve the enzyme′s ability to hydrolyze carbapenems. In the analysis of the flanking sequences of the blaOXA genes, Class I integrons were identified in four bacterial strains. The variable regions of these integrons carried three distinct patterns of resistance gene cassettes: aac( 6′) -Ib-blaOXA-1247-ant( 3′′) -Ia, aac( 6′) -Ib-blaOXA-1248 and aac( 6′) -Ib- blaIMP-45-blaOXA-1-catB3. Among these, the strain BJ2326 carried a class I integron that was connected to the downstream IS CR1 element to form a composite class I integron structure, additionally carrying the resistance gene blaPER-1. Out of the 223 non-wild-type P. aeruginosa strains, 127 strains exhibited non-wild-type profiles to the four beta-lactam antibiotics MEM, CAZ, FEP, and TZP, with the combination of MEM+CAZ+FEP being the most prevalent, representing 57.0% of the total. Conclusions:The blaOXA genes in 241 clinical P. aeruginosa strains showed diversity. Some blaOXA genes had a co-transfer risk with the metallo-β-lactamase resistance gene blaIMP-45. Among the 11 newly discovered blaOXA subtypes, the new subtype OXA-1247 may have carbapenemase activity and potential for horizontal transfer.

The Gram-negative bacteria Escherichia coli Nissle 1917(EcN)is a probiotic that has been widely applied in clinical practice.With its notable tolerance,safety,and antimicrobial proper-ties,EcN demonstrates the capacity to colonize the intestine and establish a symbiotic relationship with the host,thereby balancing the intestinal microbiota.Extensive studies have elucidated the mechanisms through which EcN regulates the host's innate immune response enhancing the host's ability to combat pathogenic invasions.On one hand,EcN strengthens the integrity of the intestinal mucosal barrier by upregulating the expression of tight junction proteins.On the other hand,EcN's diverse array of secreted,and released components,including lipopolysaccharides,K5 capsule,fla-gellum proteins,and fimbria,play roles in modulating the host's innate immune response.These components interact with host cell receptors and modulate the activities of immune cells and cyto-kines production.By consolidating the current understanding of EcN's probiotic properties,this ar-ticle provides a comprehensive overview of the intricate mechanisms underlying EcN-mediated reg-ulation of the host's innate immune response.Such insights offer theoretical support for leveraging EcN's advantages and improving immune function and overall health maintenance in the host.

Objective:To analyze the carriage status, subtype distribution and flanking gene sequence characteristics of oxacillinases (OXA enzyme) in 241 clinical strains of Pseudomonas aeruginosa, and assess their roles in the drug resistance of Pseudomonas aeruginosa and ability to horizontally transfer across species. Methods:Clinical P. aeruginosa isolates were collected from four hospitals in Sanya, Tangshan, Zhangjiakou, and Beijing. The prevalence of oxacillinases and their flanking gene sequences was analyzed by whole-genome sequencing (NGS) and bioinformatic approaches. Results:A total of 241 isolates of P. aeruginosa were gathered, and 35 blaOXA subtypes were identified through screening of 252 blaOXA genes. These genes were classified into three subfamilies: blaOXA-50-like (241, 95.6%), blaOXA-1-like (9, 3.6%) and blaOXA-10-like (2, 0.8%). Among these, 11 subtypes (11, 31.4%) were novel blaOXA subtypes. Nine of these belonged to the blaOXA-50-like subfamily and were designated as blaOXA-1244, blaOXA-1245, blaOXA-1246, blaOXA-1250, blaOXA-1252, blaOXA-1253, blaOXA-1254, blaOXA-1255, and blaOXA-1256. The remaining two belonged to the blaOXA-10-like subfamily and were named blaOXA-1247 and blaOXA-1248. Compared to the amino acid sequence of OXA-10, the newly identified subtype OXA-1247 exhibited a mutation at position 117, where a valine was replaced by a leucine. This change was thought to improve the enzyme′s ability to hydrolyze carbapenems. In the analysis of the flanking sequences of the blaOXA genes, Class I integrons were identified in four bacterial strains. The variable regions of these integrons carried three distinct patterns of resistance gene cassettes: aac( 6′) -Ib-blaOXA-1247-ant( 3′′) -Ia, aac( 6′) -Ib-blaOXA-1248 and aac( 6′) -Ib- blaIMP-45-blaOXA-1-catB3. Among these, the strain BJ2326 carried a class I integron that was connected to the downstream IS CR1 element to form a composite class I integron structure, additionally carrying the resistance gene blaPER-1. Out of the 223 non-wild-type P. aeruginosa strains, 127 strains exhibited non-wild-type profiles to the four beta-lactam antibiotics MEM, CAZ, FEP, and TZP, with the combination of MEM+CAZ+FEP being the most prevalent, representing 57.0% of the total. Conclusions:The blaOXA genes in 241 clinical P. aeruginosa strains showed diversity. Some blaOXA genes had a co-transfer risk with the metallo-β-lactamase resistance gene blaIMP-45. Among the 11 newly discovered blaOXA subtypes, the new subtype OXA-1247 may have carbapenemase activity and potential for horizontal transfer.

Objective To investigate the activity of Acorus tatarinowii extracts against dust mites, and to isolate and characterize active ingredient of A. tatarinowii extracts. Methods The essential oil components were extracted from A. tatarinowii rhizome powder by rotary evaporation with methanol as solvents, followed by petroleum ether extraction and rotary evaporation. The essential oil was mixed with Tween-80 at a ratio of 1:1 and diluted into concentrations of 1.000 00%, 0.500 00%, 0.250 00%, 0.125 00%, 0.062 50% and 0.031 25%, while diluted Tween-80 served as controls. A. tatarinowii essential oil at each concentration (200 μL) was transferred evenly to filter papers containing 100 adult mites, with each test repeated in triplicate, and controls were assigned for each concentration. Following treatment at 25 °C and 75% relative humidity for 24 h, the mean corrected mortality of mites was calculated. The essential oil components were separated by silica gel column chromatography, and the essential oil was prepared in the positive column of medium pressure; and then, each component was collected. Silica gel column chromatography was run with the mobile phase that consisted of petroleum ether solution containing 10% ethyl acetate and pure ethyl acetate, detection wavelength of 254 nm, positive silica gel column as the chromatography column, and room temperature as the column temperature. Each component of the purified A. tatarinowii essential oil was diluted into 1.000 00% for acaricidal tests. The components with less than 100% acaricidal activity were discarded, and the remaining components were diluted into 50% of the previous-round tests for subsequent acaricidal tests. The components with acaricidal activity were subjected to high-performance liquid chromatography, liquid chromatography-mass spectrometry and pulsed-Fourier transform nuclear magnetic resonance spectroscopy. The structure of active monomer compounds was determined by standard spectral library retrieval and literature review. Results A. tatarinowii essential oil at concentrations of 1.000 00%, 0.500 00%, 0.250 00% and 0.125 00% killed all dust mites, and the corrected mortality was all 100%. Exposure to A. tatarinowii extracts at an effective concentration of 0.062 50% for 24 hours resulted in 94.33% mortality of dust mites. Six components (A to F) were separated using gel column chromatography, and components D and E both showed a 100% acaricidal activity against dust mites at a concentration of 0.50000%. In addition, Component D was identified as isoeugenol methyl ether, and Component E as β-asarinol. Conclusion The extract of A. tatarinowii essential oil has acaricidal activity, and the isoeugenol methyl ether shows a remarkable acaricidal activity against dust mites.

Objective:To explore the effect of sub-inhibitory concentration of imipenem on the bio-activities of methicillin resistant Staphylococcus aureus(MRSA) and illuminate the inhibitory effects of carbapenem antibioty on the activity of MRSA and their mechanisms,and to provide the basis for using the carbapenem antibiotics in the treatment of MRSA infection.Methods:Five ST239 type of MRSA clinical isolates were selected and were co-cultured with 1/10 and 1/2 minimal inhibitory concentration (MIC) of imipenem for 1.5,6.0 and 12.0 h,which were divided into control group(no imipenem),1/10MIC group(1/10MIC of imipenem),and 1/2MIC group(1/2MIC of imipenem).Fluorescent quantitative real-time PCR method was used to determine the relative mRNA expression levels of virulence-related genes fibronectin A(fnbA),staphylococcal protein A(spa),α-hemolysin(Hla),leukocidin D(lek-D),leukocidin E(lek-E),and enterotoxin A in various groups;Spectrophotometry was used to detect the proliferation activity of MRSA strains in various groups in vitro.Results:After co-culture for 6.0 and 12.0 h,the proliferation activities of 5 trains of MRSA in 1/2MIC group in vitro were significantly decreased compared with control group (P<0.01).The relative mRNA expression levels of 6 virulence-related genes of 5 strains of MRSA in 1/10MIC and 1/2MIC groups were significantly decreased compared with control group(P<0.01).After co-culture for 12.0 h,the mRNA expressions of all the tested virulence-related genes were not found.Conclusion:The sub-inhibitory concentration of imipenem shows obviously inhibitory effect on the mRNA expressions of multiple virulence-related genes of ST 239 type of MRSA strains,and higher concentration of imipenem can suppress the proliferation of MRSA strains in vitro.Imipenem shows the potential value in the treatment of the severe MRSA infected patients.

Background Conjunctivochalasis is an age-related inflammatory ocular surface disease manifesting redundant,loose conjunctiva folds.Studies showed that conjunctivochalasis often accompanies with inflammatory response,indicating that a variety of inflammatory cytokines are involved in pathogenesis of conjunctivochalasis.Objective This study attempted to investigate the expressions of pentraxin-3 (PTX-3) and tumor necrosis factor-α stimulated gene-6 (TSG-6) proteins in fibroblasts of conjunctivochalasis.Methods The protocol was approved by Ethic Committee of Putuo Hospital affiliated Shanghai University of Traditional Chinese Medicine.Thirteen eyes of 13 patients with conjunctivochalasis,16 eyes of 16 patients with age-related cataract and 16 eyes of 15 patients with pterygium were included in Putuo Hospital Affiliated to Shanghai University of Traditional Medicine from January,2011 to June,2012.The samples of conjunctival tissue were collected in the patients during surgery under the informed consent,and fibroblasts were cultured and passaged by explant culture method.Content of PTX-3 and TSG-6 proteins in cell supernatant was detected by ELISA.Results Translucent poor,dark black area was around the cell overflow.Cultured cells of third generation showed long shuttle type,uniform size,radiated out in all directions,and oval nuclei was sited in the cytoplasm,surrounded by varying the length of cross-linking of cell processes.The concentrations of PTX-3 protein in cell supernatant were (2 182.33 ± 738.68) pg/ml in the conjunctivochalasis group,which were higher than (738.32±335.00) pg/ml in the age-related cataract group and (981.37±416.04)pg/ml in the pterygium group,showing a significant difference among the three groups (F =6.474,P=0.032).The contents of TSG-6 proteins in cell supernatant were (59.10±6.52) pg/ml,(53.99± 11.16) pg/ml and (35.01±5.33)pg/ml in the conjunctivochalasis group,pterygium group and age-related cataract group,with a significant difference among the three groups (F =7.421,P =0.024),and contents of TSG-6 proteins in the agerelated cataract group was lowest,however,no significant difference was found in the TSG-6 contents between the conjunctivochalasis group and the pterygium group (P＞0.05).Conclusions Inflammatory reaction participates in the pathogenesis and development of conjunctivochalasis,up-regulation of PTX-3 and TSG-6 expression in fibroblasts might partakes in the pathogenesis of conjunctivochalasis.

Objective To study the promotive effect of neovascularization on rats with cerebral infarction by nasal administration of granulocyte colony-stimulating factor.Methods A blinded,vehicle-controlled study of ING-CSF and IHG-CSF administration was performed by intraluminal middle cerebral artery occlusion (MCAO) model.All Sprague-Dawley rats were randomly divided into sham-operation group,model group,INNS group,IHGCSF group and ING-CSF group.The neurologic behavioral tests were assessed after reperfusion 72 h.Mter 72 h of MCAO,the brains of rats were stainned with TTC and the infarcted volume was calculated by computer image analysis.The expression of vascular endothelial growth factor (VEGF) in the brain was determined by immune-histochemistry.The density of angiogenesis in the brain was counted under fluorescence microscope.Results The score of neurological function of ING-CSF group(3.90± 1.65)was improved significantly compared with the IHG-CSF group (10.55±2.19) at the point of 72 h after cerebral infarction (P＜0.01).The cerebral infarct volume of ING-CSF group((20.01±3.29) ％) was reduced evidently compared with the IHG-CSF group((33.48±4.49) ％) at 72 h (P＜ 0.01);while the cerebral infarct volume of INNS group ((60.20±7.72) ％)was not markedly different compared with the model group((61.49±6.41)％) at 72 h (P＞0.05).The expression of VEGF in the brains of ING-CSF group was significantly higher than other groups at 72 h.Conclusion Intranasal administration G-CSF can improve neurological function and vascular angiogenesis in rats following MCAO.

0.05); while in the 12th month, BMD markedly increased in group A and decreased in group B (P 0.05) but ?-CTX level increased after treatment (P