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Background: Oncostatin M (OSM) is a secreted cytokine of the interleukin (IL)-6 family that induces biological effects by activating functional receptor complexes of the common signal transducing component glycoprotein 130 (gp130) and OSM receptor β (OSMR) or leukaemia inhibitory factor receptor (LIFR), which are mainly involved in chronic inflammatory and cardiovascular diseases. The effect and underlying mechanism of OSM/OSMR/LIFR on the development of cardiac hypertrophy remains unclear. Methods and results: OSMR-knockout (OSMR-KO) mice were subjected to aortic banding (AB) surgery to establish a model of pressure overload-induced cardiac hypertrophy. Echocardiographic, histological, biochemical and immunological analyses of the myocardium and the adoptive transfer of bone marrow-derived macrophages (BMDMs) were conducted for in vivo studies. BMDMs were isolated and stimulated with lipopolysaccharide (LPS) for the in vitro study. OSMR deficiency aggravated cardiac hypertrophy, fibrotic remodelling and cardiac dysfunction after AB surgery in mice. Mechanistically, the loss of OSMR activated OSM/LIFR/STAT3 signalling and promoted a proresolving macrophage phenotype that exacerbated inflammation and impaired cardiac repair during remodelling. In addition, adoptive transfer of OSMR-KO BMDMs to WT mice after AB surgery resulted in a consistent hypertrophic phenotype. Moreover, knockdown of LIFR in myocardial tissue with Ad-shLIFR ameliorated the effects of OSMR deletion on the phenotype and STAT3 activation. Conclusions: OSMR deficiency aggravated pressure overload-induced cardiac hypertrophy by modulating macrophages and OSM/LIFR/STAT3 signalling, which provided evidence that OSMR might be an attractive target for treating pathological cardiac hypertrophy and heart failure. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biodegradation of biochar-adsorbed trichloroethylene (TCE) by Dhc 195 was studied. • 87.5 % of biochar-adsorbed TCE was biodegraded to ethene within 63 days. • Adsorption capacity of biochar remained 80.4% after 5-time bioregeneration cycles. • Electron transfer from Dhc 195 to TCE was mediated by biochar for biodegradation. • Biodegradation of adsorbed TCE required more VB 12 but had a wider pH tolerance. Biochars was widely employed to immobilize chlorinated aliphatic hydrocarbons (CAHs) in groundwater. Biodegradation of adsorbed CAHs may be able to regenerate biochars, but was scarcely explored. In this study, therefore, biodegradation of trichloroethylene (TCE) adsorbed on a biochar prepared at 700 °C (WBC700) by Dehalococcoides mccartyi 195 (Dhc 195) was investigated. Aqueous TCE was completely degraded to ethene by Dhc 195 within 28 days, while 87.5 % of WBC700-adsorbed TCE was degraded to ethene within 63 days. The slower biodegradation of WBC700-adsorbed TCE could be attributed to its lower accessibility to Dhc 195 caused by the steric effects of WBC700. The adsorption capacity of WBC700 for TCE remained 80.4 % after five adsorption-bioregeneration cycles, indicating that the microbial degradation could be a highly efficient method to regenerate biochars. The microbial degradation was mainly through the electron transfer from Dhc 195 to TCE mediated by biochars as electron conductor or shuttle, but was not assisted by desorption or extracellular redox active species. Compared with biodegradation of aqueous TCE, the biodegradation of WBC700-adsorbed TCE by Dhc 195 had a wider pH tolerance and required more VB 12 , due to the buffer effect and adsorption of WBC700, respectively. The obtained results could provide a cost-effective method of biochar regeneration for CAHs removal in groundwater. [ABSTRACT FROM AUTHOR]

The constitutive model of the frozen soil-structure interface is a critical component of frozen soil mechanics research, and the surface roughness plays a significant role in determining the interaction between the soil and structure. Most of the previous research about the interface roughness mechanical behavior is based on numerical simulations, and these methods mainly depend on empirical and semi-empirical approaches to determine parameters. However, there is a lack of sufficient research on the internal mechanisms of micro-mechanical deformation of the contact surface based on roughness. To elucidate the impact of roughness on the deformation mechanism and mechanical behavior of frozen soil, a series of cryogenic direct shear tests and a binary medium model based on the interface of frozen soil-structure were conducted. The test was carried out at −4 °C under different normal load and roughness conditions. The test results showed that the shear curve of the specimen interface presented brittle failure, and the stress peak was evident at this temperature. Moreover, the shear zone was introduced to explain the change of roughness on the mechanical behavior of the samples. A binary medium constitutive model was established to depict the overall mechanical behavior of the interface during prepeak shear with different roughness. The simulated roughness, displacement, and shear stress are in good agreement with the measured data. The effectiveness of the model is evaluated by correlated factors, and it is verified that the model can properly depict the change of roughness on the mechanical characteristics of the interface. • Established an improved roughness algorithm that considers various factors. • The relationship between the surface roughness and the shear stress is analyzed. • A binary medium constitutive model considering the effect of roughness is proposed. [ABSTRACT FROM AUTHOR]