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Objective: To investigate the molecular characterization and antimicrobial resistance of CA-MRSA(community-associated methicillin-resistant Staphylococcus aureus) strains isolated from clinical inpatientsto provide evidence for prevention and treatment of CA-MRSA infections. Methods: Isolates of S. aureus from hospitalized patients were collected within 24 h after admission from April 2014 to Dec. 2015, and mecA gene was detected to distinguish MRSA from MSSA (methicillin-sensitive Staphylococcus aureus). Genotypic CA-MRSA strains carrying SCC mec Ⅳ/Ⅴ were obtainedfor further analysis of molecular epidemiologic characters by spa-typing and MLST（multilocus -sequence typing）. Based on the CLSI (Clinical and Laboratory Standards Istitute) guidelines, disk diffusion method was used to test drug susceptibility of CA-MRSA strains. Moreover, the presence of pvl virulence gene was detected by PCR. Results: A total of 147 strains of S. aureus including 58 MRSA strains were collected from hospitalized patients. By SCCmec typing, 9 CA-MRSA strains (SCCmec Ⅳ 3; SCCmec Ⅴ 6) were detected. All CA-MRSA strains developed resistance against different non-β-lactams, among which 8 strains developed drug-resistanceagainst aminoglycosides (mainly kanamycin) and 8 strains developed drug-resistance against erythromycin and clindamycin mediated by erm(B) mainly. Molecular typing revealed that the main CA-MRSA clone was t437-ST59, and other clones were t034-ST804, t127-ST1, t008-ST8 and t437-ST338. In addition, 5 out of 9 CA-MRSA strains were pvl gene positive. Conclusions: More pathogenic CA-MRSA strains are invading healthcare-associated settings and developing more resistance against non-β-lactams, indicating that the CA-MRSA should be closely monitored in hospitals.

The dual binding behavior of the metallylenes TH2 (T = Si, Ge, Sn, Pb) with some selected Lewis acids (T'H3F, T' = Si, Ge, Sn, Pb) and bases (N2, HCN, CO, and C6H6) has been investigated by using the high-level quantum chemical method. Two types (type-A and type-B) of tetrel-bonded complexes can be formed for TH2 due to their ambiphilic character. TH2 act as Lewis bases in type-A complexes, and they act as Lewis acids in type-B ones. CO exhibits two binding modes in the type-B complexes, one of which is TH2···CO and the other is TH2···OC. The TH2···OC complexes possess a weaker binding strength than the other type-B complexes. The TH2···OC complexes are referred to as the type-B2 complexes, and the other type-B complexes are referred to as the type-B1 complexes. The type-A complexes exhibit a relatively weak binding strength with Eint (interaction energy) values ranging from –7.11 to –15.55 kJ/mol, and the type-B complexes have a broad range of Eint values ranging from −9.45 to −98.44 kJ/mol. The Eint values of the type-A and type-B1 complexes go in the order SiH2 > GeH2 > SnH2 > PbH2. The AIM (atoms in molecules) analysis suggests that the tetrel bonds in type-A complexes are purely closed-shell interactions, and those in most type-B1 complexes have a partially covalent character. The EDA (Energy decomposition analysis) results indicate that the contribution values of the three energy terms go in the order electrostatic > dispersion > induction for the type-A and type-B2 complexes, and this order is electrostatic > induction > dispersion for the type-B1 complexes. [ABSTRACT FROM AUTHOR]

Methods: The intermolecular interactions between the heavy-atom analogues of acetylene T2H2 (T = Si, Ge, Sn, Pb) and HCN have been investigated by theoretical calculations at the CCSD(T)/aug-cc-pVTZ//MP2/aug-cc-pVDZ level. Results: The global energy minimum of T2H2 is the butterfly structure A, and another energy minimum is the planar structure B. Both structures A and B exhibit the dual behavior when binding with HCN. The various hydrogen bond (HB), dihydrogen bond (DB) and tetrel bond (TB) complexes can be found according to the MEP maps of T2H2. One TB and three HB complexes formed between structure A and HCN can be located for Si2H2 and Ge2H2. One TB, two HB and one DB complexes formed between structure A and HCN can be located for Sn2H2 and Pb2H2. Four TB and one HB complexes formed between structure B and HCN can be located for all the T2H2. The geometries and binding strengths of the complexes are compared and analyzed. Conclusions: The interactions in these complexes are generally weak, and the interaction energies of these complexes range from −0.53 to −8.23 kcal/mol. The interaction energies of the TB complexes are larger than those of the corresponding HB and DB complexes for structure A···HCN systems. The relative binding strength of the four TB complexes exhibits different order for different structure B···HCN systems, which is consistent with the MEP maps of the isolated monomers. [ABSTRACT FROM AUTHOR]

Abstract: Uniform and monodispersed TiO2 hollow spheres with nanoporous titania shell are prepared successfully by using carboxyl-functionalized polystyrene spheres as templates. The results show that TiO2 hollow spheres pose a stable reversible capacity of 230 mAhg−1 at 33.5 mAg−1 and 120 mAhg−1 at 1675 mAg−1, which are higher than that of bulk TiO2 with coarse grain. The discharge process of TiO2 hollow spheres are suggested containing three consecutive stages: the formation of tetragonal Li x TiO2 solid solution, coexistence of two-phase mixture of Li0.05TiO2 and Li0.5TiO2 at 1.75 V and additional lithium storage in the surface. The superior high rate and high capacity performance of prepared TiO2 hollow spheres are due to its highly reversible additional surface capacities and accommodation of phase transformation within nanostructure. [Copyright &y& Elsevier]

Background: Conditional survival (CS) considers the time already survived after surgery and may provide additional survival information. The authors sought to construct and validate novel conditional survival nomograms for the prediction of conditional overall survival (OS) and cancer-specific survival (CSS) of colorectal signet-ring cell carcinoma (SRCC) patients., Methods: Patients diagnosed with stage I-III SRCC between 2010 and 2019 were identified from the Surveillance, Epidemiology, and End Results database. The formula calculating CS was: CS(x|y) = S(x+y)/S(x), where S(x) represents the survival at x years. CS nomograms were then constructed to predict the 5-year conditional OS and CSS, followed by internal validation., Results: A total of 944 colorectal SRCC patients were finally identified in this study. The 5-year OS and CSS improved gradually with additional survival time. Univariate and multivariate Cox regression analysis conducted in training set revealed that age, race, T stage, LNR, and perineural invasion were independent risk factors for both OS and CSS. Two nomograms with considerable predictive ability were successfully constructed [area under the curve (AUC) for OS: 0.788; AUC for CSS: 0.847] and validated (AUC for OS: 0.773; AUC for CSS: 0.799) for the prediction of 5-year OS and CSS, based on the duration of 1-4 years post-surgery survival., Conclusions: The probability of achieving 5-year OS and 5-year CSS in colorectal SRCC patients improved gradually with additional time. Conditional nomograms considering survival time will be more reliable and informative for risk stratification and postoperative follow-up., Competing Interests: The authors have no conflicts of interest.Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

The metal-organic frameworks/cotton fabric composites (MOFs/CFCs) have emerged as a new type of prospective materials for environmental cleanup, due to their convenient recyclability and high removal efficiency towards hazardous pollutants. However, their practical applications are limited by complicated synthetic conditions, insufficient interface bonding and poor adsorption capacity. Herein, for the first time, a robust ethylenediaminetetraacetic acid (EDTA)-functionalized MOFs/CFC is prepared based on UiO-66-NH 2 crystals by using EDTA dianhydride as the cross-linking agent, and applied for simultaneous removal of heavy metals and dyes, as well as degradation of chemical warfare agents. The as-prepared EDTA-UiO-66-NH 2 /CFC shows extraordinary monocomponent adsorption performance with maximum adsorption capacity of 158.7, 126.2, 131.5, 117.4 and 104.5 mg/g for Cd(II), Cu(II), methylene blue, crystal violet and safranin O, respectively. Interestingly, in metal-dyes binary system, the uptake of Cu(II) by EDTA-UiO-66-NH 2 /CFC increases significantly when co-existing high concentration of dyes. The results indicate that the synergistic and simultaneous removal of both dyes and metal from complex systems can be realized by EDTA-UiO-66-NH 2 /CFC via multiple mechanisms. The EDTA-UiO-66-NH 2 /CFC also exhibits an outstanding catalytic performance for degrading dimethyl 4-nitrophenylphosphate. Besides, it can be reused for several times without obvious decrease of its adsorption and catalysis efficiencies. More impressively, the cross-linking reaction approach can not only anchor UiO-66-NH 2 crystals firmly onto cotton fabric, but also facilitate in-situ formation of abundant adsorption sties on the adsorbent surface. Therefore, this work offers a simple and versatile synthetic strategy to develop high-performance environmental material for multiple pollutants remediation., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Objectives: The present study aimed to determine whether bone marrow mesenchymal stem cell-derived microvesicles (MSC MVs) were effective in restoring lung tissue structure, and to assess the potential role of miRNAs in the pathogenesis and progression of acute respiratory distress syndrome (ARDS)., Materials and Methods: ARDS was induced by lipopolysaccharide in male C57BL/6 mice. The degree of lung injury was assessed by histological analysis, lung's wet weight/body weight, and protein levels in the bronchoalveolar lavage fluid (BALF). Sequencing was performed on the BGISEQ-500 platform. Differentially expressed miRNAs (DEMs) were screened with the DEGseq software. The target genes of DEMs were predicted by iRNAhybrid, miRanda, and TargetScan., Results: Compared with LPS-injured mice, MSC MVs reduced lung water and total protein levels in the BALF, demonstrating a protective effect. 52 miRNAs were differentially expressed following treatment with MSC MVs in ARDS mice. Among them, miR-532-5p, miR-223-3p, and miR-744-5p were significantly regulated. Gene Ontology (GO) function and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses revealed the target genes were mainly located in the cell, organelle, and membrane. Furthermore, KEGG pathways such as ErbB, PI3K-Akt, Ras, MAPK, Toll, and Wnt signaling pathways were the most significant pathways enriched by the target genes., Conclusion: MSC MVs treatment was involved in alleviating lung injury and promoting lung tissue repair by dysregulated miRNAs.

A novel ruthenium(II) polypyridyl complex bearing 1,8-naphthyridine was successfully designed and synthesized. This complex was fully characterized by EI-HRMS, NMR, and elemental analyses. The recognition properties of the complex for various metal ions were investigated. The results suggested that the complex displayed high selectivity and sensitivity for Cu 2+ and Fe 3+ ions with good anti-interference in the CH 3 CN/H 2 O (1:1, v / v ) solution. The fluorescent chemosensor showed obvious fluorescence quenching when the Cu 2+ and Fe 3+ ions were added. The detection limits of Cu 2+ and Fe 3+ were 39.9 nmol/L and 6.68 nmol/L, respectively. This study suggested that this Ru(II) polypyridyl complex can be used as a high selectivity and sensitivity fluorescent chemosensor for Cu 2+ and Fe 3+ ions.

A new zirconia-based stationary phase (DPZ) was prepared by modifying zirconia with dodecylamine-N,N-dimethylenephosphonic acid (DDPA). DDPA adsorbs on zirconia with only one phosphonic group, and another is free. Besides the hydrophobic interaction provided by non-polar dodecyl, DPZ also has dipolar interaction, ion-exchange and electrostatic repellent interaction provided by the free phosphonic group and amino group at different conditions. Separations of bases on this stationary phase were achieved with satisfaction due to the various retention mechanisms. The influences of methanol content, pH value, ion type and ion strength of mobile phase were studied in detail.