Objective To investigate the risk rate of infection with SARS coronavirus in health care workers in an designated hospital, and to assess the effectiveness of the isolation system in prevention of nosocomial transmission of SARS. Methods Questionnaire was submitted to all health care workers related with SARS patients, and ELISA assay was performed to detect IgG antibody against SARS coronavirus for all of them. Results 450 health care workers were submitted the same questionnaire, 445 questionnaires were returned, and 441 blood samples were collected. It was confirmed that all health care workers involved had complied with the isolation guidelines as formulated by the authority of the hospital. Two hundred and sixty persons out of 441 were classified into the group who had close contact with SARS patients and/or SARS materials. Among these 260 workers, IgG antibody against SARS Coronavirus was detected in 5 of them, who had either worked in the SARS ward, CCU (where 3 SARS probable cases had stayed for a short term), paediatric ward, center for sample transference, or laundry. Therefore, there was no statistically significant difference in the risk rate between the group of workers who had close contact with SARS patients and/or SARS materials and the group without contact. Conclusion The current isolation system against SARS was effective, though might not perfect.

Objective To investigate the protective effects of different doses of fasudil on hepatic ischemia/reperfussion (I/R) injury in rats with liver cirrhosis.Methods Cirrhosis was induced in rats by subcutaneous injection of 60％ carbon tetrachloride (CC14) corn oil solution (0.4 ml/100 g) twice a week for twelve weeks.Five percent of alcohol was given intermittently in drinking water.Then 40 cirrhotic rats were randomized into 4 groups.In sham group,sham operation was performed.In I/R group A and B,whole rat livers were subjected to warm ischemia by clamping the hepatic artery and portal vein for 30 min.In group A,the selected rats were pretreated with low-dose fasudil 1 mg/kg (intraperitoneal injection) 30 min before the induction of ischemia,and in group B,with high-dose 10 mg/kg.The serum levels of alanine aminotransferase (ALT) and endothelin-1 (ET-1),and the liver tissue superoxide dismutase (SOD)activity,malondialdehyde (MDA) content,the expression of HIF-1a (hypoxia-inducible fador-1a) were measured after reperfusion for 6 hours.Hepatic pathologic changes were observed under microscope.Results Compared with I/R group,the serum ALT,AST,ET-1 levels,MDA content and the expression of HIF-1 a were markedly decreased in group B,while the SOD activity significantly increased (P ＜ 0.05).And the pathologic changes were less severe in group B.Conclusion The high-dose fasudil markedly lessened the expression of HIF-1a,up-regulated the concentration of SOD,and lowered the levels of MDA and ET-1,protecting against heoatic ischemia/reperfusion injury in rats with liver cirrhosis.

Objective To investigate the protective effect of arbutin against CCl4-induced hepatic fibrosis in mice and explore the underlying mechanisms. Methods Twenty-four C57BL/6 mice were randomly divided into control group, model group, and low-and high-dose arbutin treatment (25 and 50 mg/kg, respectively) groups. Mouse models of liver fibrosis were established by intraperitoneal injection of CCl4, and arbutin was administered daily via gavage for 6 weeks. After the treatments, serum biochemical parameters of the mice were tested, and liver tissues were taken for HE staining, Sirius Red staining and immunohistochemical staining. RT-qPCR was used to detect the mRNA levels of α-SMA, Pdgfb, Col1α1, Timp-1, Ccl2 and Tnf-α, and Western blotting was performed to detect α-SMA protein expression in the liver tissues. In the cell experiment, the effect of arbutin treatment for 24 h on THP-1 and RAW264.7 cell migration and recruitment was examined using Transwell migration assay and DAPI staining; The changes in protein levels of Akt, p65, Smad3, p-Akt, p-p65, p-Smad3 and α-SMA in arbutin-treated LX-2 cells were detected with Western blotting. Results Arbutin treatment significantly lowered serum alanine aminotransferase and aspartate aminotransferase levels, alleviated liver tissue damage and collagen deposition, and reduced macrophage infiltration and α-SMA protein expression in the liver of the mouse models (P<0.05 or 0.001). Arbutin treatment also significantly reduced CCl4-induced elevation of α-SMA, Pdgfb, Col1α1, Timp-1, Ccl2 and Tnf-α mRNA levels in mice (P<0.05). In the cell experiment, arbutin treatment obviously inhibited migration and recruitment of THP-1 and RAW264.7 cells and lowered the phosphorylation levels of Akt, p65 and Smad3 and the protein expression level of α-SMA in LX-2 cells. Conclusion Arbutin ameliorates liver inflammation and fibrosis in mice by inhibiting hepatic stellate cell activation via reducing macrophage recruitment and infiltration and suppressing activation of the Akt/NF-κB and Smad signaling pathways.

Objective To investigate the protective effect of arbutin against CCl4-induced hepatic fibrosis in mice and explore the underlying mechanisms. Methods Twenty-four C57BL/6 mice were randomly divided into control group, model group, and low-and high-dose arbutin treatment (25 and 50 mg/kg, respectively) groups. Mouse models of liver fibrosis were established by intraperitoneal injection of CCl4, and arbutin was administered daily via gavage for 6 weeks. After the treatments, serum biochemical parameters of the mice were tested, and liver tissues were taken for HE staining, Sirius Red staining and immunohistochemical staining. RT-qPCR was used to detect the mRNA levels of α-SMA, Pdgfb, Col1α1, Timp-1, Ccl2 and Tnf-α, and Western blotting was performed to detect α-SMA protein expression in the liver tissues. In the cell experiment, the effect of arbutin treatment for 24 h on THP-1 and RAW264.7 cell migration and recruitment was examined using Transwell migration assay and DAPI staining; The changes in protein levels of Akt, p65, Smad3, p-Akt, p-p65, p-Smad3 and α-SMA in arbutin-treated LX-2 cells were detected with Western blotting. Results Arbutin treatment significantly lowered serum alanine aminotransferase and aspartate aminotransferase levels, alleviated liver tissue damage and collagen deposition, and reduced macrophage infiltration and α-SMA protein expression in the liver of the mouse models (P<0.05 or 0.001). Arbutin treatment also significantly reduced CCl4-induced elevation of α-SMA, Pdgfb, Col1α1, Timp-1, Ccl2 and Tnf-α mRNA levels in mice (P<0.05). In the cell experiment, arbutin treatment obviously inhibited migration and recruitment of THP-1 and RAW264.7 cells and lowered the phosphorylation levels of Akt, p65 and Smad3 and the protein expression level of α-SMA in LX-2 cells. Conclusion Arbutin ameliorates liver inflammation and fibrosis in mice by inhibiting hepatic stellate cell activation via reducing macrophage recruitment and infiltration and suppressing activation of the Akt/NF-κB and Smad signaling pathways.

Objective:To study the molecular phylogeny and virulence gene profile of Francisella salimarina. Methods:Phylogenetic analysis of Francisella salimarina was performed based on the global genome data of related Francisella species on GenBank database. The consistency in phylogenetic analysis based on single marker genes (such as 16S rRNA gene, rpoB gene and mdh gene) and the core genome as compared. Virulence genes and antibiotic resistance genes were annotated using the virulence factor database (VFDB) and the Comprehensive Antibiotic Resistance Database (CARD), respectively. The virulence of Francisella salimarina was analyzed with a Galleria mellonella (greater wax moth) infection model using Francisella philomiragia ATCC 25015 T as reference strain. Results:The phylogenetic analysis revealed that Francisella salimarina was closely related to Francisella philomiragia. The phylogenetic tree based on mdh gene was highly similar to that based on the core genome. Francisella salimarina could be differentiated from other related species by 16S rRNA gene or mdh gene, with the latter being more accurate. Eight Francisella salimarina strains carried multiple virulence genes, mainly involved in secretion, adhesion, immune regulation, motility and stress survival. Moreover, beta-lactam resistance gene blaFPH was identified in all eight strains. Francisella salimarina showed high lethality in the Galleria mellonella infection model, which was similar to Francisella philomiragia ATCC 25015 T. Conclusions:Francisella salimarina was a rare pathogen with similar pathogenicity to Francisella philomiragia. The mdh gene could be used as a molecular target for rapid identification of Francisella salimarina.

Based on the holistic view of "spleen-vessels-heart-spirit" system， this article explores the pathogenesis and progression of atrial fibrillation. It is proposed that the onset of atrial fibrillation is due to failure of the spleen to transport and disharmony of blood vessels； phlegm and blood stasis obstructing the collaterals and damage to the heart structure are the basis of its pathogenesis； the unclear mind and disorder of body and spirit are the causes of its progression. Based on the characteristics of pathological changes in different stages of the disease， it is proposed that early treatment should focus on restoring the middle jiao， clearing and promoting blood vessels， using modified Yigong Powder （异功散）； during the progression of the disease， treatment should remove blood stasis and phlegm， nourish heart and protect the pulse， using self-prescribed modified Mengshi Tongmai Decoction （礞石通脉汤）； meanwhile， calming mind and stabilizing palpitations， and regulating spirit should be sequentially incorporated， with self-prescribed Jiazao Ningmai Decoction （甲枣宁脉汤） or Shenying Dingji Decoction （参英定悸汤） and modified as appropriate. Clinical treatment should focus on the whole disease course of atrial fibrillation， implementing stage-based treatments to enable early intervention and holistic regulation.

Depsides and depsidones have attracted attention for biosynthetic studies due to their broad biological activities and structural diversity. Previous structure‒activity relationships indicated that triple halogenated depsidones display the best anti-pathogenic activity. However, the gene cluster and the tailoring steps responsible for halogenated depsidone nornidulin ( 3) remain enigmatic. In this study, we disclosed the complete biosynthetic pathway of the halogenated depsidone through in vivo gene disruption, heterologous expression and in vitro biochemical experiments. We demonstrated an unusual depside skeleton biosynthesis process mediated by both highly-reducing polyketide synthase and non-reducing polyketide synthase, which is distinct from the common depside skeleton biosynthesis. This skeleton was subsequently modified by two in-cluster enzymes DepG and DepF for the ether bond formation and decarboxylation, respectively. In addition, the decarboxylase DepF exhibited substrate promiscuity for different scaffold substrates. Finally, and interestingly, we discovered a halogenase encoded remotely from the biosynthetic gene cluster, which catalyzes triple-halogenation to produce the active end product nornidulin ( 3). These discoveries provide new insights for further understanding the biosynthesis of depsidones and their derivatives.