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Objective Antimicrobial peptides are widely present in nature, with many of the antimicrobial peptides having antimicrobial activity against Gram‐positive and Gram‐negative bacteria, fungi, parasites, and even coated viruses. Internal fixation of fractures is a reliable technique. However, the fracture is difficult to heal and internal fixation is not easy to maintain after infection. This study aims to verify the antibacterial effect of cationic peptide LL‐37 on Staphylococcus aureus, explore the anti‐biofilm effects of LL‐37, and compare the effects of the cationic peptide LL‐37 and Cefalexin in treatment of postoperative infection of femoral fracture in vivo. Methods The Staphylococcus aureus was clinically isolated from one patient with clinical infection after the fracture fixation at Wuxi 9th People's Hospital. The cationic peptide LL‐37 was synthesized by Shanghai Apeptide Co. Ltd. To compare the effects of the cationic peptide LL‐37 and Cefalexin in the treatment of postoperative infection of femoral fracture in vivo, 63 rabbits with internal fixation of femoral fractures were inoculated intravenously with clinically isolated pathogenic bacteria suspensions. Rabbits in the treatment groups were treated with peptide LL‐37 and Cefalexin after surgery. Rabbits in the control groups were treated with physiological saline after surgery. The biofilms on internal fixtures were harvested from euthanized rabbits 1 h, 12 h, 1 day, 2 days, and 7 days after injection of LL‐37, Cefalexin, or saline and calculated by colony count. The biofilms from treatment and control groups at 7 days were analyzed by fluorescence microscopy. Blood samples were collected at 1 h, 12 h, 1 day, 2 days, and 7 days following peptide LL‐37 and Cefalexin injection. Results The results were compared statistically using Student's t‐test or two‐way analysis of variance (ANOVA). Cationic peptide LL‐37 showed significant inhibitory effects on clinically isolated Staphylococcus aureus (P

Background Osteoarthritis (OA) is a chronic complex multifactorial joint disease, and a major degenerative form of arthritis. Existing studies on the association between polymorphisms of the IL-17 gene and the risk of OA in different populations have yielded conflicting findings. Aim To investigate the association between polymorphisms of the IL-17 gene and the risk of OA. Methods We conducted a meta-analysis by systematically searching databases, including PubMed, EMBASE, MEDLINE, Cochrane Library, and Google Scholar to evaluate this association by calculating pooled odds ratios with 95% confidence intervals. Moreover, subgroup analyses stratified by ethnicity and OA type were also conducted. Results In a total of 6 citations involving 8 studies (2131 cases and 2299 controls), 4 single nucleotide polymorphisms were identified. Of these 4 polymorphisms, 2 (rs2275913, rs763780) were common in five case-control studies. Together, the pooled results revealed that the A allele and genotype AA/GA of the rs2275913 polymorphism, and the C allele and genotype CC of the rs763780 polymorphism in the IL-17 gene increased the risk of OA. Furthermore, stratification analyses by ethnicity and OA type showed that the rs2275913 polymorphism increased the risk of OA among Asians and in knee/hip OA, respectively. In addition, stratification analyses also revealed that the rs763780 polymorphism increased OA risk among both Asians and Caucasians in knee/hip OA. Conclusion The rs763780 polymorphism of the IL-17F gene increased the risk of OA, whereas the rs2275913 polymorphism of the IL-17A gene increased the risk of OA only among Asians. Due to the limitations of this study, these findings should be validated in future studies.

Although the research on the risk factors of anterior communicating artery (AComA) aneurysm has made great progress, the independent effect of each risk factor on the rupture of AComA aneurysm is controversial among different studies. We will perform a protocol for systematic review and meta-analysis to investigate risk factors for AComA aneurysm rupture and quantify their independent effects.A systematic search according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols guidelines in PubMed, Embase, and the Cochrane Library databases was conducted from inception to August 31, 2021 for published studies concerning risk factors for AComA aneurysm rupture. In the absence of statistical heterogeneity (ie, P .10 and I2 50%), we will use a fixed-effects model to pool the results across sufficient studies. Otherwise, we will present the results employing the random-effects model. Quality assessment of the included studies will be evaluated using the Newcastle-Ottawa Scale. Statistical analyses will be performed using Stata16 (Stata Corporation, College Station, TX, USA) software.The findings of this study will be submitted to peer-reviewed journals for publication.This systematic review will provide evidence to determine the risk factors that affect the rupture of the AComA aneurysm and quantify their independent effects.Since the proposed study uses pre-published data, ethical approval is not required.CRD42021284262. (https://www.crd.york.ac.uk/PROSPERO/).

Gene mutations play important roles in tumour development. In this study, we identified a functional histone H2B mutation H2BL-T11C, causing an amino acid variation from Leu to Pro (L3P, H2BL-L3P). Cells overexpressing H2BL-L3P showed stronger proliferation, colony formation, tumourigenic abilities, and a different cell cycle distribution. Meanwhile, the c-Myc expression was elevated as evident by RNA-seq. We further revealed that an H2BK5ac-H2BK120ubi crosstalk which regulates gene transcription. Moreover, EdU staining demonstrated an important role of c-Myc in accelerating cell cycle progression through the G1/S checkpoint, while treatment with 10058-F4, an inhibitor of the c-Myc/MAX interaction, alleviated the abnormal cell proliferation and cell cycle distribution in vitro and partially inhibited tumour growth in vivo. The mutation of amino acid L3P is associated with tumour progression, suggesting patients carrying this SNP may have higher risk of tumour development.

BACKGROUND: Osteoarthritis (OA) is a chronic complex multifactorial joint disease, and a major degenerative form of arthritis. Existing studies on the association between polymorphisms of the IL-17 gene and the risk of OA in different populations have yielded conflicting findings. AIM: To investigate the association between polymorphisms of the IL-17 gene and the risk of OA. METHODS: We conducted a meta-analysis by systematically searching databases, including PubMed, EMBASE, MEDLINE, Cochrane Library, and Google Scholar to evaluate this association by calculating pooled odds ratios with 95% confidence intervals. Moreover, subgroup analyses stratified by ethnicity and OA type were also conducted. RESULTS: In a total of 6 citations involving 8 studies (2131 cases and 2299 controls), 4 single nucleotide polymorphisms were identified. Of these 4 polymorphisms, 2 (rs2275913, rs763780) were common in five case-control studies. Together, the pooled results revealed that the A allele and genotype AA/GA of the rs2275913 polymorphism, and the C allele and genotype CC of the rs763780 polymorphism in the IL-17 gene increased the risk of OA. Furthermore, stratification analyses by ethnicity and OA type showed that the rs2275913 polymorphism increased the risk of OA among Asians and in knee/hip OA, respectively. In addition, stratification analyses also revealed that the rs763780 polymorphism increased OA risk among both Asians and Caucasians in knee/hip OA. CONCLUSION: The rs763780 polymorphism of the IL-17F gene increased the risk of OA, whereas the rs2275913 polymorphism of the IL-17A gene increased the risk of OA only among Asians. Due to the limitations of this study, these findings should be validated in future studies.

Objective Asiatic acid (AA) has been suggested to inhibit pulmonary and hepatic fibrosis, while its influence on cardiac fibrosis remains unclear. We aimed to investigate whether AA could inhibit overpressure-induced cardiac fibrosis in spontaneous hypertension rats (SHRs). Method SHRs were treated with AA (20 mg kg−1 day−1) for 12 weeks and cultured cardiac fibroblasts (CFs) were treated with Ang II (10−7 mol/L) in vitro. Markers of oxidative stress were measured and extent of cardiac fibrosis was evaluated with Sirius Red staining. Levels of Superoxide Dismutase (SOD), Malondialdehyde (MDA), reactive oxygen spices (ROS) and Glutathione (GSH) were measured by using commercial assay kits. Collagen deposition was detected. The expression of relative protein and mRNA was measured by Western blot and real-time PCR, respectively. Results AA reduced systolic blood pressure, attenuated myocardial hypertrophy, reduced college deposition and the expression of collagen I and III, connective tissue growth factor, and plasminogen activator inhibitor-1, in mRNA and protein levels, with inhibition of TGF-β1 expression, phosphorylation of Smad2/3, and increase of Smad7 expression. AA reduced malondialdehyde and reactive oxygen spices, while increased the activities of superoxide dismutase and glutathione, accompanied with elevation of nuclear translocation of nuclear-factor erythroid 2-related factor 2 (Nrf2) and expression of heme oxygenase (HO-1) and NAD(P)H dehydrogenase [quinone] 1 (NQO-1) in vivo and in vitro. Moreover, pretreating CFs with siRNA for Smad7 or Nrf2 both partially reversed the inhibition of AA on Ang II-induced cardiac fibrosis. Conclusion AA attenuates pressure overload-induced cardiac fibrosis via enhancing of Nrf2/HO-1 and suppressing TGF-β1/Smads phosphorylation.

Statistical shrinkage is a potential statistical method to improve the accuracy of signal detection results and avoid spurious associations detected by disproportionality analyses. In this study, we introduced statistical shrinkage influence on disproportionality methods in spontaneous reporting system in China.We added the shrinkage parameters in the numerator and denominator, denoted as in the formula of disproportionality analysis. The shrinkage parameters were subjectively set to between 0 and 5, with an interval of 0.1. Adverse drug reaction product label database was deemed as a proxy of golden standard to evaluate the effect of statistical shrinkage. Reports in the years of 2010-2011 were extracted from the national spontaneous reporting system database as the data source for analysis in this study.When α was around 0.5, the Youden index reached the maximum for each disproportionality methods in this study. The value of 0.6 was suggested as the most appropriate statistical shrinkage parameter for reporting odds ratio and proportional reporting ratio and 0.2 for information component based on the spontaneous reporting system of China.

The synthesis and structural characterization of two novel RuII complexes (1 and 2) with tridentate pyridine-2,6-diimine ligands are described. In both compounds, ortho-CH bonds from the phenyl or phenyl-like rings produce unexpected CH···π interactions with ruthenium-α,α'-diimine chelate rings. This insight is thought to provide new structural evidence for the metalloaromaticity of the chelate rings in the ruthenium complexes studied. The molecular geometry of complex 1 is remarkably similar to S4 symmetrical geometry, which is also a consequence of the four CH···π(chelate ring) interactions working cooperatively. In contrast, there are only two pairs of these interactions working in complex 2 because of the steric effects and electronic influences caused by the methyl-group substitutions. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)

In order to probe the mechanism of the phenomena of seismic electromagnetic radiation (EMR), we have completed field experiment on EMR caused by explosiom of rocks. In the experiments, the data of medium-low freguency (

This paper describes a method of robust vibration control of a cantilever elastic beam in a uniform smooth wind stream. As the actuator, a pair of piezoelectric columns is fixed under base aluminium plates at which the cantilever beam is clamped. Its natural frequencies are calculated by the transform matrix method, and then the mode coordinate is introduced to establish state equations of this control system. A robust controller is designed to suppress galloping of the cantilever beam by applying H∞ control theory. Simulation and experiment were carried out, and the results were compared with those of LQR control. It was found that robust stability and nominal performance were achieved, and an excellent control effect was obtained by H∞ control. The usefulness of the proposed control technique is verified by simulation and experiment.

Nonlinear axisymmetric shape oscillations have been revealed through experiments conducted with large-amplitude forced vertical vibrations of a magnetic fluid column supported by a magnetic field in the presence of gravity. Those nonlinear shape oscillations are characterized by the jumping phenomena, mode transition, and subharmonic motions.

A digital optimal regulator technique is introduced to the problem of vibration control of a cantilever beam. A pair of piezoelectrit cells is adhered to the upper and lower surfaces of the beam and used as the actuator. Influences of the mass and the rigidity of the actuator are taken into account in the analysis, and the equations of motion for the beam-control system are derived by applying the trsnsfer matrix method. Simulated transient response of the beam is compared with the experimental result. It is found that the effect of vibration suppression is obtained by means of the present technique which compensates for the delay arising from the computation time.

High-precision phase-difference measurement is a key technology for a phase-shift laser range finder. In order to improve the estimation accuracy of phase difference between two sinusoidal signals with identical frequency, the phase-shift correlation method is described. Theoretical analysis shows that the conventional cross-correlation method will bring notable deviations when the true phase difference is close to 0° or 180° in the presence of noise. For reducing the influence of noise, two step calculations--phase-shift autocorrelation and phase-shift cross correlation--are used in the phase-shift correlation method. The estimation bias is eliminated by phase-shift autocorrelation in which the autocorrelation is calculated between the 2π phase-shifted signal and the original signal, and the periodic errors are eliminated by phase-shift cross correlation in which the phase difference is estimated when the true phase difference is near 90° or 270°. The effect of frequency drift on the phase difference is also discussed. The experiment results show that the maximum error of the conventional method is about 0.15°, while the estimation error of our proposed method is much less than 0.01° under the same conditions.