[The role of Nrf2 in the alteration of tight junction protein expression in choroid plexus epithelial cells created by lanthanum-activated MMP9].

Objective: To investigate the effect of nuclear factor erythroid 2-related factor 2 (Nrf2) in the alteration of tight junction protein expression in choroid plexus epithelial cells created by lanthanum-activated matrix metalloproteinase 9 (MMP9) . Methods: In October 2020, immortalized rat choroid plexus epithelial cell line (Z310) cells were used as the blood-cerebrospinal fluid barrier in vitro, and were divided into control group and 0.125, 0.25, 0.5 mmol/L lanthanum chloride (LaCl(3)) treatment group. After treating Z310 cells with different concentrations of LaCl(3) for 24 hours, the morphological changes of Z310 cells were observed under inverted microscope, the protein expression levels of MMP9, occludin and zonula occludens-1 (ZO-1) were observed by cellular immunofluorescence method, and the protein expression levels of MMP9, tissue inhibitors of metalloproteinase1 (TIMP1) , occludin, ZO-1 and Nrf2 were detected by Western blotting. The level of reactive oxygen species (ROS) in cells was detected by flow cytometry. Results: Compared with the control group, Z310 cells in the LaCl(3) treatment group were smaller in size, with fewer intercellular junctions, and more dead cells and cell fragments. The expression level of MMP9 protein in cells treated with 0.25 and 0.5 mmol/L LaCl(3) was significantly higher than that in the control group (P<0.05) , and the expression level of TIMP1 and tight junction proteins occudin and ZO-1 was significantly lower than that in the control group (P<0.05) . Compared with the control group, the ROS production level in the 0.25, 0.5 mmol/L LaCl(3) treatment group was significantly increased (P<0.05) , and the Nrf2 protein expression level in the 0.125, 0.25, 0.5 mmol/L LaCl(3) treatment group was significantly decreased (P<0.05) . Conclusion: Lanthanum may increase the level of ROS in cells by down regulating the expression of Nrf2, thus activating MMP9 to reduce the expression level of intercellular tight junction proteins occludin and ZO-1.

[Epidemiological characteristics of Yersinia enterocolitica in patients with diarrhea from 2013 to 2019 in Pudong New Area, Shanghai].

Objective: To investigate the epidemiological characteristics of Yersinia enterocolitica in patients with diarrhea in Pudong New Area, Shanghai. Methods: Active surveillance of diarrhea was conducted in 14 sentinel hospitals (three tertiary-level hospitals, nine secondary-level hospitals, and two primary-level hospitals) from January 2013 to December 2019 in Pudong New Area of Shanghai, China base on their location, catchment area, and patient volume. Cold enrichment method was used to isolate Y. enterocolitica and further detection of bioserotype, virulence genes and antimicrobial susceptibility of the isolates were conducted. The difference of rates was determined using chi-square test or Fisher's exact test. Results: A total of 12 941 diarrhea cases were included, and 0.7% (88/12 941) cases were confirmed with Yersinia enterocolitica infection. 67.0% (59/88) cases were single infection, 33.0% (29/88) cases were mixed infections. Detection rates of Y. enterocolitica increased annually (0.3%-1.2%) and were highest in children<5 years of age (1.1%, 37/3 218) and in spring (1.1%, 32/2 998) (χ2 were 18.64 and 9.76, respectively, P<0.05). 58.0% (51/88) cases had watery diarrhea, 15.9% (14/88) had fever and 14.8% (13/88) had vomiting. The predominant bioserotypes were 3/O:3 (53.4%, 47/88), followed by 1A/O:8 (15.9%, 14/88) and 1A/O:5(6.8%, 6/88), respectively. Bioserotype 3/O:3 counted for the highest proportions (89.2%, 33/37) in children <5 years of age. All the strains of bioserotype 3/O:3 harbored ail, ystA, yadA and virF genes, which encoded pathogenic Y. enterocolitica. 11/14 strain of 1A/O:8 and 4/6 strains of 1A/O:5 harbored ystB gene. Most strains were resistant to ampicillin (80.7%,71/88) and amoxicillin/clavulanic acid (71.6%,63/88), and 63.8% (56/88) strains were multidrug resistance (MDR). The difference of antimicrobial resistance rates between 3/O:3 and non 3/O:3 was statistically significant in ampicillin, cefoxitin, nalidixic acid, tetracycline and ampicillin/sulbactam (χ2 was 14.68, 43.80, 41.86, 30.54 and 5.07, respectively, P<0.05). Conclusion: The detection rate of Yersinia enterocolitica was higher in children than in adults in Pudong New Area, Shanghai. The predominant bioserotype was pathogenic 3/O:3 with multidrug resistance.

Structural transitions for 2D systems with competing interactions in logarithmic traps.

We propose a confinement model and study numerically the structural properties of particles with competing interactions in logarithmic traps (i.e., the confinement potential is a logarithmic function). A rich variety of cluster structures are observed as a function of trap steepness, trap size, and particle density. In addition to the consistent results with previous studies for a harmonic confinement, we observe some new stable structures, including a hybrid cluster structure consisting of clumps surrounded by a circular stripe, parallel stripes, or homogeneous voids surrounded by a ringlike arrangement of clumps, and a gear-like cluster with fringed outer rims evenly arranged along the circumference. Our work reveals that such self-organized structures arise due to the radial density reconfiguration in a finite confined system corresponding to the unconstrained systems, which is controlled by the interplay between the long-range repulsions and the attractions to the minimum of the confinement potential. Such results are likely relevant in understanding the structural properties of confined mermaid systems.

[Clinical features and outcome of treatment for novel coronavirus pneumonia: a meta-analysis].

Objective: To investigate the clinical features and outcome of treatment for novel coronavirus pneumonia. Methods: Literature on novel coronavirus pneumonia was retrieved from PubMed and EMBASE databases. The relevant data was extracted and a meta-analysis was performed using StatsDirect statistical software V.2.8.0 to calculate the combined odds ratio. Results: Seven studies were included, consisting of 1594 cases. The meta-analysis result showed that the most common clinical symptoms of the novel coronavirus pneumonia were fever (91.6%) and cough (64.5%), followed by dyspnea (32.8%) and sputum (28.1%). Headache (10.5%), sore throat (11.2%), hemoptysis (3.2%), diarrhea (6.6%) and the other symptoms were relatively rare. Aspartate aminotransferase (29%), alanine transaminase (22.7%), and total bilirubin (11.7%) levels were elevated, except for serum albumin levels (80.4%). The common therapeutic agents used were antibiotics (87.7%), antiviral drugs (75.5%), and glucocorticoids (26.6%), while antifungal agents (7.7%) were used in few. Mechanical ventilation (13.4%), extracorporeal membrane oxygenation (1.9%), and continuous renal replacement therapy (3.8%) were used in severe cases. The rate of mortality in hospital was 7.7%, respectively. Heterogeneity between studies was significant; however, subgroup and sensitivity analysis had failed to identify clear sources of heterogeneity. Conclusion: Fever, cough and liver dysfunction are the main clinical manifestations of this disease and the mortality rate is low.

[Value of intravoxel incoherent motion diffusion weighted imaging in evaluating the microstructure changes in white matter hyperintensities].

Objective: To investigate the value of intravoxel incoherent motion diffusion weighted imaging (IVIM DWI) in evaluating microstructure changes in elderly white matter hyperintensities (WMH) patients and to analyze the correlation between IVIM parameters and severity grading and cognitive scores. Methods: Sixty-two WMH patients in Zhejiang Hospital were collected from December 2014 to March 2018 and underwent conventional magnetic resonance (MR) plain scan and diffusion weighted imaging with different b values. The age was 60-92(74±10) years with 37 males, 25 females. The severity of WMH was assessed by T(2) fluid attenuated inversion recovery (FLAIR) sequence and Fazekas score,which were divided into two subgroups. Slow diffusion coefficient (D), fast diffusion coefficient (D(*)) and perfusion fraction (f) from IVIM parameters of double exponential model were compared between regions of WMH (deep WMH (DWMH) and periventricular WMH (PWMH)) and surrounding normal white matter (NWM).The Shapiro-Wilk test was used for normality tests, Kruskal-Wallis tests and Dwass-Steel-Critchlow-Fligner (DSCF) procedure were used for the comparison among these parameters. Furthermore, Wilcoxon two-sample test was used for the comparisons between different severity. Pearson correlation analysis was performed to determine whether these D, D(*), f values were correlated with the mini mental state examination (MMSE) scores. Results: D(D)WMH (0.83(0.72,0.99)×10(-3) mm(2)/s), D(PWMH)((1.13±0.25)×10(-3) mm(2)/s) were significantly higher than D(NWM) ((0.71±0.05)×10(-3) mm(2)/s)(P<0.01). f (DWMH) ((8.94%(7.46%,11.67%)), f (PWMH)(8.34%(6.73%,9.96%)) were significantly higher than f (NWM)(6.71%±1.72%)(P<0.01).D in DWMH were significantly lower than that in PWMH(P<0.01), there's no statistically difference between other groups. D in severe WMH (both DWMH and PWMH) were significantly higher than that in mild WMH (P=0.000 1, P=0.04). Only f in PWMH were positively associated with the MMSE scores (r=0.326 5,P<0.05). Conclusions: IVIM DWI can noninvasively assess the variation of microstructure diffusion and perfusion in WMH in one sequence,which may objectively reflect the severity of these lesions. This method has important clinical significance for better assessment and management of this disease.

[The study of pleural effusion supernatant cell-free tumor DNA in tumor mutational burden assessment of advanced lung cancer].

Objective: To evaluate the feasibility of cell-free tumor DNA in pleural effusion supernatant for assessing the tumor mutational burden (TMB) of advanced lung cancers. Methods: From December 2016 to August 2018, 34 lung cancer patients (19 males and 15 females) with pleural effusion were enrolled at Zhongshan Hospital, Fudan University. The median age of the patients was 65 (range, 34-85) years. Before systemic or local antitumor therapy, tumor specific mutations in tumor tissue, pleural effusion supernatant, pleural effusion sediment, and plasma samples from these patients were examined using targeted next-generation sequencing, and TMB levels were calculated respectively. Subgroup analysis was based on smoking history and driver mutation status. Statistical differences were determined using SPSS 16.0 software, and individual groups were compared using the one-way analysis of variance (ANOVA) and LSD-t test. Results: The median TMB level of pleural effusion supernatant was 6.23 mutations/Mb, similar to that of tumor tissue (6.23 vs 6.86 mutations/Mb, t=1.174, P=0.245), but significantly higher than that of pleural effusion sediment (2.49 mutations/Mb, t=3.044, P=0.003) and plasma (2.49 mutations/Mb, t=2.464, P=0.016). Compared with tumor tissue in TMB assessment, pleural effusion supernatant had a positive percentage agreement of 52% (9/17), and a negative percentage agreement of 65% (11/17). Subgroup analysis showed that the TMB level was higher in smokers (n=11) than that in non-smokers (n=23, 14.4 vs 5.4 mutations/Mb, t=3.238, P=0.003). Conclusion: For advanced lung cancer patients with pleural effusion, pleural effusion supernatant is a promising substitute to tumor tissue for TMB assessment, which is a potential biomarker for immunotherapy.

Comparison of target-controlled infusion and manual infusion for propofol anaesthesia in children.

BACKGROUND: One major criticism of prolonged propofol-based total i.v. anaesthesia (TIVA) in children is the prolonged recovery time. As target-controlled infusion (TCI) obviates the need to manually calculate the infusion rate, the use of TCI may better match clinical requirements, reduce propofol dose, and shorten recovery time. METHODS: Children of ASA grade 1, aged 1-12 yr, were recruited and randomly assigned to TCI or manual infusion. Children in the TCI group had propofol delivered by TCI. Children for manual infusion had a loading dose of 2.5 mg kg-1 with subsequent infusion rates of 15, 13, 11, 10, and 9 mg kg-1 h-1. Attending anaesthesiologists adjusted the propofol dosage to keep the Bispectral Index™ (BIS) between 40 and 60. RESULTS: Seventy-four children completed the study. The time taken to extubate the trachea after cessation of propofol was 15.1 (5.5) and 16.2 (6.1) min for children who had TCI and manual infusion, respectively (P=0.42). The mean propofol infusion rate was 16.7 [standard deviation (sd) 4.2] mg kg-1 h-1 in the TCI group and 14.6 (3.1) mg kg-1 h-1 in the manual infusion group (P=0.036). The percentage of time when BIS was >60 was significantly lower in the TCI than the manual infusion group [10.2% (18.4%) vs 23.2% (26.3%), P=0.016]. DISCUSSION: Use of TCI led to higher propofol doses but not prolonged recovery time in children compared with manual infusion. It was associated with a greater percentage of time when the BIS was in the desired range and it may be an easier method for titration of propofol administration during anaesthesia or sedation. CLINICAL TRIAL REGISTRATION: ChiCTR-IOD-16010147.

[The concomitant gene alterations impact the therapeutic efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors in advanced non-small cell lung cancer patients with epidermal growth factor receptor sensitive mutation].

Objective: To investigate if concomitant gene alterations impact the therapeutic efficacy of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) in advanced non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) sensitive mutation. Methods: From November 2016 to December 2017, 51 patients (19 males and 32 females, age 37-85 years) with histology or cytology diagnosed,locally advanced or metastatic NSCLC from Zhongshan Hospital Fudan University were prospectively recruited in the study. All patients harboring EGFR sensitive mutation detected by a 123 lung cancer specific gene panel of next-generation sequencing(NGS) analysis were under treatment of EGFR-TKIs. Multi-factors analysis of the correlation between EGFR-TKIs efficacy and concomitant gene alterations were analyzed by multivariate Cox regression model. Results: 82% of the NSCLC patients with EGFR mutation presented concomitant gene alterations with an average number of 2.1. Patients not harboring concomitant gene alterations had a longer median progression free survival (mPFS: not reached vs 8.8 m, P=0.008). Those who had less than 2 concomitant genes had a higher objective response rate[ORR: 52% (17/33) vs 33% (6/18) , P=0.251]and better mPFS (13.8 vs 8.0 m, P=0.003). The top 3 concomitant gene alterations were TP53 gene mutation(55%, 28/51), EGFR gene amplification (26%, 13/51) and RB1 gene mutation (18%,9/51) respectively. The mPFS of EGFR-TKI treatment in patients with either one of these 3 concomitant genes was 8.0, 8.0, and 6.0 months respectively, significantly shorter than those without one of the 3 gene alterations (13.8, 13.1, and 10.8 months respectively). Multivariate Cox regression revealed that concomitant gene abnormalities (P=0.036) and accompanied by RB1 gene mutation (P=0.025) were independent risk factors for the survival benefit of EGFR-TKI in the treatment of advanced NSCLC with EGFR-sensitive mutation. Conclusions: The efficacy of EGFR-TKI decreased significantly in advanced NSCLC with EGFR-sensitive mutation who had concomitant gene abnormalities, especially accompanied by more than 2 of the 3 gene alterations (TP53 gene mutation, EGFR gene amplification or RB1 gene mutation). This study suggested that the concomitant gene alterations should be an important issue for consideration when applying a personalized combination therapy for advanced NSCLC harboring EGFR sensitive mutation.

[Study of epidemic area on Tsutsugamushi disease in Taizhou from 2013 to 2014].

Objective: To study the epidemiological characteristics of tsutsugamushi disease, and to confirm the existence of the disease's epidemic foci in Taizhou. Methods: From 2013 to 2014, Dongxing town hospital and Xingqiao town hospital were selected as specimen collection sites in Jingjiang city. Blood samples (5 ml) were collected from 40 patients with acute tsutsugamushi disease. A total of 59 rodents were captured with cage night method in the survey sites at 5, 7, 9, 10, and 11 months in 2013, from which, the spleen, liver, and kidney specimens were selected. Chigger mites were captured by small blackboard method and from the ears of the captured rodents. A total of 226 small blackboards were laid, 27 mites were captured, and the samples were grounded into suspension. Nested-polymerase chain reaction and cell and tissue culture techniques were used to test the specimen from the probable patients, host animals and chigger mites. Results: Among the 40 acute tsutsugamushi disease blood samples, 29 were found to meet the test requirements, 17 were positive for orientia tsutsugamushi nucleic acid with 59% of the positive rate, and 1 stran orientia tsutsugamushi was isolated. 59 rats were captured and the density of mice was 5.5%. Among them, there were 26 Mus musculus (2.4%), 18 Rattus flavipectus (1.7%) and 15 Smelly shrew (density 1.4%). 1 Smelly shrew was tested positive for orientia tsutsugamushi nucleic acid, and the negative results were found in the other rodent specimens. 27 Chigge mites were collected by small blackboard method and the density of mites was 0.12 for each blackboard, among which 3 larvae and 24 nymphs were found. 33 Chigger mites were collected from the ears of 3 Smelly shrew, and the density of the mite was 11 per mouse. All the captured Chigger mites were identified as Leptotrombidium scutellare and 1 group of specimens of Chigger mites from the external environment were positive for orientia tsutsugamushi nucleic acid. Conclusion: There was a high density of mice in the epidemic area from May to November and the species of the chigger mites were Chigger mites in Taizhou. The nucleic acid of the oriental tsutsugamushi was detected in the patients with acute scrub typhus, rodents and vectors. According to the above-mentioned results, it was considered that the scrub typhus epidemic area of Taizhou city has the natural foci of scrub typhus.

[Treatment of single one-stage posterior atlantoaxial fixation in Chiari malformation].

Objective: To explore the effects of surgical technique of single one-stage posterior C(1-2) screw rod fixation of Chiari malformation (CM) associated with occipitalization and without atlantoaxial dislocation. Methods: A total of 23 patients with CM treated between January 2014 and October 2015 in Department of Neurosurgery of Chinese People's Liberation Army General Hospital were retrospective reviewed. All of them were diagnosis with CM associated with occipitalization and without atlantoaxial dislocation, including 8 males and 15 females, aging from 11 to 57 years (mean (35.5±10.52) years). Single one-stage posterior C(1-2) screw rod fixation with bone grafting fusion was performed. Operation time and intraoperative blood loss were recorded. Japanese Orthopaedic Association (JOA) scores and Odom rating were used to evaluate the clinical effects at pre- and post-operative. Regression of the cerebellar tonsillar was measured by MRI. The results were analyzed by paired samples t test. Results: Twenty-three patients were implanted screws successfully, the vertebral artery injury and cerebrospinal fluid leakage were not found. The mean operation time was (172.7±19.9) minutes, the intraoperative blood loss was (153.9±49.3) ml. Compared to preoperative, the JOA score increased (13.7±1.6 vs. 11.5±1.4) and the tonsillar herniation decreased ((0.8±0.6)cm vs. (1.9±0.6) cm) in the last follow-up, there were statistical difference (t=13.386, P<0.01; t=17.995, P<0.01). The results of the postoperative Odom grading were as follows: 6 cases were perfect (26.1%), 13 cases were good (56.5%), 4 cases were moderate (17.4%) and no case was poor.No signs of instrument loosen or screw broken was noticed. 100% bony fusion rate was achieved. The follow-up time was 6 to 23 months (mean (10.5±3.2) months). One case developed internal fixator related discomfort, the symptom was relieved by internal fixator removal surgery performed 4 months after the operation when osseous fusion had already been achieved. No new neurologic symptoms were observed in other 22 patients. Conclusions: The results of the study substantiates the effectiveness of single one-stage posterior fixation strategy for CM, which is associated with occipitalization and without atlantoaxial dislocation. This technique could be an alternative choice for this type of CM.

Proteomic analysis reveals the mechanisms of Mycena dendrobii promoting transplantation survival and growth of tissue culture seedlings of Dendrobium officinale.

AIMS: Dendrobium officinale is an important traditional Chinese medicinal herb. Its seedlings generally show low survival and growth when transferred from in vitro tissue culture to a greenhouse or field environment. In this study, the effect of Mycena dendrobii on the survival and growth of D. officinale tissue culture seedlings and the mechanisms involved was explored. METHODS AND RESULTS: Mycena dendrobii were applied underneath the roots of D. officinale tissue culture seedlings. The seedling survival and growth were analysed. The root proteins induced by M. dendrobii were identified using two-dimensional (2-D) electrophoresis and matrix-assisted laser desorption/ionization time-of-flight MS (MALDI-TOF-MS). Mycena dendrobii treatment significantly enhanced survival and growth of D. officinale seedlings. Forty-one proteins induced by M. dendrobii were identified. Among them, 10 were involved in defence and stress response, two were involved in the formation of root or mycorrhizae, and three were related to the biosynthesis of bioactive constituents. CONCLUSIONS: These results suggest that enhancing stress tolerance and promoting new root formation induced by M. dendrobii may improve the survival and growth of D. officinale tissue culture seedlings. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a foundation for future use of M. dendrobii in the large-scale cultivation of Dendrobiums.

Short communication: simultaneous analysis of reducing sugars and 5-hydroxymethyl-2-furaldehyde at a low concentration by high performance anion exchange chromatography with electrochemical detector, compared with HPLC with refractive index detector.

A simultaneous analysis of reducing sugars and 5-hydroxymethyl-2-furaldehyde of the Maillard reaction products was detailed. It was based on a high performance anion exchange chromatography with electrochemical detector system and an HPLC with refractive index detector. Results showed that high performance anion exchange chromatography with electrochemical detector using a CarboPac PA-1 column (Dionex Corp., Sunnyvale, CA) was more suitable for reducing sugars and 5-hydroxymethyl-2-furaldehyde determination, especially for trace analysis. The lowest detectable limit of reducing sugars and 5-hydroxymethyl-2-furaldehyde was 0.00005 mol/L in this experiment. However, HPLC with a refractive index detector always produces a tailing peak for 5-hydroxymethyl-2-furaldehyde, and mannose and fructose cannot be absolutely separated. The results of the present study could provide a more sensitive means for 5-hydroxymethyl-2-furaldehyde and reducing sugar detection.

Antibiofilm activity against Staphylococcus aureus and content analysis of Taraxacum Officinale phenolic extract.

Taraxacum Officinale, commonly called dandelion, is herbaceous perennial belonging to the family of Asteraceae, having good antibacterial effects which are related to its phenolic substances. In this study, the effect of phenolic contents as well as the antibiofilm activity against Staphylo- coccus aureus of phenolic extract from T. Officinale were evaluated in vitro. With 70% metha- nol-water (v/v) as a solvent, the dandelion was extracted by ultrasonic assisted extraction method. Subsequent identification and quantification of phenol in extract was carried out using High Performance Liquid Chromatography (HPLC). The minimum inhibitory concentration and anti- bacterial kinetic curve of dandelion phenolic extract were analyzed by spectrophotometry. Changes in extracellular alkaline phosphatase (AKP) contents, electrical conductivity, intracellular protein contents, and DNA of S. aureus after the action of dandelion phenolic extract were determined to study its effect on the permeability of S. aureus cell wall and cell membrane. The results showed that chlorogenic acid (1.34 mg/g) was present in higher concentration, followed by lute- olin (1.08 mg/g), ferulic acid (0.22 mg/g), caffeic acid (0.21 mg/g), and rutin (0.19 mg/g) in the dandelion phenolic extract. The minimum inhibitory concentration (MIC) of dandelion phenolic extract against S. aureus was 12.5 mg/mL. The antibacterial kinetic curve analysis showed that the inhibitory effect of dandelion phenolic extract on S. aureus was mainly in the exponential growth phase. After applying the dandelion phenolic extract, the growth of S. aureus was signifi- cantly inhibited entering into the decay phase early. Furthermore, after the action of dandelion, the extracellular AKP contents of S. aureus, the electrical conductivity and the extracellular protein contents were all increased. The phenolic extract also affected the normal reproduction of S. aureus. These results suggest that dandelion has an inhibitory effect on S. aureus, and the mechanism of its action was to destroy the integrity of the cell walls and cell membranes.

Nonequilibrium pattern formation in circularly confined two-dimensional systems with competing interactions.

We numerically investigate the nonequilibrium behaviors of classic particles with competing interactions confined in a two-dimensional logarithmic trap. We reveal a quench-induced surprising dynamics exhibiting rich dynamic patterns depending upon confinement strength and trap size, which is attributed to the time-dependent competition between interparticle repulsions and attractions under a circular confinement. Moreover, in the collectively diffusive motions of the particles, we find that the emergence of dynamic structure transformation coincides with a diffusive mode transition from superdiffusion to subdiffusion. These findings are likely useful in understanding the pattern selection and evolution in various chemical and biological systems in addition to modulated systems, and add a new route to tailoring the morphology of pattern-forming systems.

[Analysis on serotype and antimicrobial resistance of invasive non-typhoidal Salmonella].

Objective: To investigate the serotypes and antimicrobial resistance of seven invasive non-typhoidal Salmonella (iNTS) isolates. Methods: For 7 iNTS strains collected, serotype identification, antimicrobial susceptibility testing and whole genome sequencing were performed. We identified, annotated and analyzed the serotypes, MLST types, and antimicrobial resistance genes. Results: Among the 7 tested iNTS isolates, we found one Salmonella Typhimurium strain and two Salmonella Ⅰ 4, [5], 12: i:- strains whose MLST types were ST34, two Salmonella Enteritidis strains, one Salmonella Corvallis strain and one strain of unknown serotype with the antigenic formulae of Ⅰ 4, [5], 12: d:- (ST279 type). Six of seven strains were monophasic and the deletion or pseudogenization of Salmonella Flagellum gene might contribute to the enhancement of Salmonella invasiveness. None was found to be resistant to tigarcycline, aztreonam, amikacin, cephalosporins and carbapenem and one Salmonella Typhimurium strain was found to be co-resistant to eight classes of antimicrobials at the same time. Resistance genes were generally in accord with relative resistant phenotypes. Conclusion: The iNTS strains could show high level multi-drug resistance, indicating that close attention should be paid to the resistance of iNTS though the overall resistance might be relatively not high.

Monodispersed NiO nanoflowers with anomalous magnetic behavior.

Nickel oxide (NiO) nanoflowers, prepared by thermal decomposition, exhibit anomalous magnetic properties far below the blocking temperature, i.e., a cusp in both the zero-field-cooled and field-cooled curves at about 21 K. Detailed characterization discloses that the individual NiO nanoflower consists of porous crystals with holes (1.0-1.5 nm in size) inside. We believe that the low temperature magnetic feature observed here could be a new kind of spin transition for the uncompensated spins around the holes and will trigger more studies in other nanostructured antiferromagnetic materials.

Polycyclic aromatic hydrocarbons residues in sandstorm depositions in Beijing, China.

This study was conducted to determine the concentration of 16 polycyclic aromatic hydrocarbons (PAHs) in sandstorm depositions in Beijing, China. The PAH concentrations in 13 samples collected in Beijing ranged from 0.18 to 3.52 microg g(-1). Analysis of the sources of contamination revealed that the PAHs were derived from a coal combustion source, although various effects of traffic emissions were also observed. Furthermore, the PAH levels in Beijing tended to be higher in the southeast. Finally, the nemerow composite index revealed that the degree of pollution in the sandstorm depositions varied widely among sampling sites.

Polybrominated diphenyl ethers in the soil of typical industrial city.

Linfen is generally recognized as one of the most polluted industrial cities in China. Indeed, Linfen is affected by heavy polluting industries and faces pollution by polybrominated diphenyl ethers (PBDEs). For this study, ten surface soil samples covering all of Linfen were collected and analyzed for 42 BDE congeners. The total PBDEs concentration ranged from 0.064 to 136.1 ng g−1. Moreover, source analysis indicated that PBDEs may be associated with the prevalent use of Deca-BDE in the industrial area of the city. Furthermore, higher levels of PBDE contamination were observed in south Linfen due to the distribution of industrial plants.

Composition, distribution, and characterization of polycyclic aromatic hydrocarbons in soil in Linfen, China.

A total of 10 surface soil samples representing the entire area of Linfen City were collected and analyzed for the presence of 16 polycyclic aromatic hydrocarbons. The total polycyclic aromatic hydrocarbon concentration ranged from 1.1 to 63.7 microg g(-1). Analysis of the sources of contamination revealed that polycyclic aromatic hydrocarbons in the soil were derived from combustion sources. Specifically, the primary source of polycyclic aromatic hydrocarbons was coal combustion, but the samples were also effected to varying degrees by traffic emissions. Furthermore, increased levels of contamination were observed in northeast Linfen due to the distribution of industrial plants.

Composition, distribution, and characterization of polybrominated diphenyl ethers in sandstorm depositions in Beijing, China.

This study was conducted to determine the concentration of 8 polybrominated diphenyl ethers (PBDEs) in sandstorm depositions in Beijing, China. The PBDE concentrations in 10 samples collected in Beijing ranged from 8.47 to 29.02 ng g(-1), with BDE-209 as the predominant congener (>85%). Principal component analysis revealed that the major source of PBDEs in Beijing may be potentially associated with deca-BDE. Furthermore, increasing PBDE contamination was observed from northwest to east Beijing. Finally, possible factors affecting contamination of the sandstorm depositions were subsequently explored revealing a significant correlation between SigmaPBDEs and the minimum particle size of the sandstorm deposition samples.