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Wei Tang,1,2,* Ying Liu,3,* Xin Li,2 Guiyun Leng,2 Ju Gao,2 Yawu Wang,2 Jie Yao,2 Zhou Liu,2 Qiang Zhou,2 Yuanhong Xu1 1Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, 230022, People’s Republic of China; 2Department of Clinical Laboratory, The Second Affiliated Hospital of Anhui Medical University, Hefei, 230601, People’s Republic of China; 3High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, People’s Republic of China*These authors contributed equally to this workCorrespondence: Yuanhong Xu, Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, 218 Jixi Road, Shushan District, Hefei, Anhui, 230022, People’s Republic of China, Tel +86 135 0569 4447, Fax +86 551 6292 2125, Email xyhong1964@ahmu.edu.cnPurpose: This study aimed to investigate the microbiological characteristics of clinically isolated Staphylococcus aureus with different hemolytic phenotypes in China.Materials and Methods: Using the three-point inoculation method, the hemolytic phenotypes of 1295 clinically isolated S. aureus strains were detected and categorized. Antimicrobial susceptibility testing of all strains was performed using a VITEK 2 Compact System. After sample size matching, plasma coagulase activity, catalase activity, mRNA expression of hemolysin genes (hla, hlb, hlc, and hld), biofilm formation, growth kinetics, inflammatory response of macrophages and cytotoxicity of S. aureus with different hemolytic phenotypes using the rabbit plasma kit, the catalase test on slides, qRT-PCR, crystal violet staining, the microcultivation assay, the ELISA kits, and the CCK-8 assay, respectively.Results: Seven categories of hemolytic phenotypes were identified. Accordingly, strains were categorized into seven different groups, including S. aureus with complete hemolytic phenotype (SCHP), S. aureus with weak hemolytic phenotype (SWHP), S. aureus with incomplete hemolytic phenotype 1 (SIHP-1), SIHP-2, SIHP-3, SIHP-4 and SIHP-5, the last three of which were reported for the first time. Except for the hemolytic phenotype, all seven groups differed in clinical isolation rates, antibiotic resistance profile, plasma coagulase activity, mRNA expression of hemolysin genes, biofilm formation, growth kinetics, inflammatory response of macrophages, and cytotoxicity.Conclusion: S. aureus with different hemolytic phenotypes have distinctive microbiological characteristics. Clinical microbiologists need to be vigilant about the hemolytic phenotypes when culturing S. aureus strains, and actively enhance communication with clinicians to optimize the treatment of infection.Keywords: Staphylococcus aureus, hemolytic phenotype, hemolysin, microbiological characteristics, antibiotic resistance

Air can have an adverse effect on the performance of an aero-engine lubrication system. A numerical analysis was conducted to explore the influence of inlet void fraction and pipe layout on the characteristics of oil-gas two-phase flow in a 90° elbow. The pipes were arranged horizontally and vertically with inlet void fractions of 0.05-0.15. The laws governing flow velocity, void fraction, and pressure along the pipe were determined separately. The results revealed the formation of large-scale vortices with high gas volume fractions inside both types of elbows, which exacerbate oil-gas separation and cause additional head loss. The maximum pressure drop was observed at approximately one pipe diameter downstream of the elbow outlet, which initially increases with the inlet void fraction and then gradually stabilizes. Asymmetric secondary flow vortices in the horizontal elbow were found to enhance oil-gas separation and accelerate lubricating oil to greater extent than in a vertical elbow under the same conditions. Consequently, the maximum pressure drop caused by flowing through the horizontal elbow is higher than that in the vertical elbow. [ABSTRACT FROM AUTHOR]

The robustness of nonlinear systems subjected to external random excitation is studied using the Lyapunov exponent concept. The one-dimensional perturbed system is expressed in terms of ordinary differential equations to obtain the function of the Lyapunov exponent. The stationary probability density function is then obtained by solving the Fokker-Planck equation for the system. Actual applications to several example problems reveal that the Lyapunov exponent doesnot reflect the qualitative changes in the steady-state probability density function.

Tumour cells change their metabolic patterns to support high proliferation rates and cope with oxidative stress. The lncRNA ELFN1-AS1 is highly expressed in a wide range of cancers and is essential to the proliferation and apoptosis of tumour cells. Nevertheless, its function in the metabolic reprogramming of tumour cells is unclear. Here we show that ELFN1-AS1 promotes glucose consumption as well as lactate and NADPH production. Database searching, bioinformatics analysis, RNA immunoprecipitation (RIP) and RNA pull-down assays show that ELFN1-AS1 enhances glucose-6-phosphate dehydrogenase ( G6PD) expression and activates the pentose phosphate pathway (PPP) by promoting TP53 degradation. In addition, luciferase reporter assay and chromatin immunoprecipitation (ChIP) show that YY1 binds to the ELFN1-AS1 promoter to promote transcriptional activation of ELFN1-AS1. Consistent with the in vitro experiments, knockdown of ELFN1-AS1 impedes the growth of tumours transplanted into mice by inhibiting the expression of G6PD. In conclusion, this study reveals that ELFN1-AS1 activates the PPP, and validates the regulatory role of the YY1/ ELFN1-AS1/ TP53/ G6PD axis in colorectal cancer.