Myocardial microRNAs (myo-miRs) are released into the circulation after acute myocardial infarction (AMI). How they impact remote organs is however largely unknown. Here we show that circulating ...myo-miRs are carried in exosomes and mediate functional crosstalk between the ischemic heart and the bone marrow (BM). In mice, we find that AMI is accompanied by an increase in circulating levels of myo-miRs, with miR-1, 208, and 499 predominantly in circulating exosomes and miR-133 in the non-exosomal component. Myo-miRs are imported selectively to peripheral organs and preferentially to the BM. Exosomes mediate the transfer of myo-miRs to BM mononuclear cells (MNCs), where myo-miRs downregulate CXCR4 expression. Injection of exosomes isolated from AMI mice into wild-type mice downregulates CXCR4 expression in BM-MNCs and increases the number of circulating progenitor cells. Thus, we propose that myo-miRs carried in circulating exosomes allow a systemic response to cardiac injury that may be leveraged for cardiac repair.
The paper aims to investigate the influence of basalt fiber (BF) on the crack resistance of the asphalt mixture and conduct a mechanical analysis. First, two typical asphalt mixtures, namely AC-13 ...and SMA-13, were designed. The impact of BF on the mixture design results was analyzed. Then, several macroscopic tests, namely the four-point bending test, indirect tensile test, and semicircular bending test (SCB), were conducted to assess the effect of BF on the cracking resistance of asphalt mixtures. Finally, the influence of BF on the cracking resistance of asphalt mixtures was analyzed based on an environmental scanning electron microscope (ESEM) observation. The results show that: (1) BF increases the optimal asphalt content of AC13 and decreases the optimal asphalt content of SMA-13, which is caused by the different asphalt-absorption capacity of BF and lignin fiber (LF). (2) BF enhances both the fatigue crack resistance and temperature crack resistance of asphalt mixtures. The enhancement on the SMA-13 is more significant, indicating that the enhancement of BF on asphalt mixtures is related to the type of aggregate gradation. (3) BFs in the asphalt mixture lap each other to form a spatial network structure. Such structure can effectively improve the crack resistance of the mixture by dispersing the load stress and preventing the flow of asphalt mastic. The study results provide an effective method to design crack-resistant asphalt mixtures.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The interfacial properties between the asphalt mastic and fibers plays an essential role in the fiber-enhanced asphalt mixture properties. However, there is a lack of comprehensive studies on the ...indicators to evaluate the interfacial interaction ability of fibers with the asphalt mastic. Therefore, this paper selected three types of basalt fibers (denoted as A-BF, B-BF and C-BF) coated with different impregnating agents to prepare the fiber asphalt mastic. The Dynamic Shear Rheometer (DSR) test-based indicators, pull-out strength, and adhesion work were used to access the fiber asphalt mastic interfacial interaction ability. The differences between different indicators were compared and analyzed. The results show that all the selected indicators in this paper can effectively reflect the different fiber asphalt mastic interfacial properties. The evaluation results with different indicators are consistent. The interfacial interaction between fibers and the asphalt mastic increases with increasing temperature. The evaluation result with adhesion work is the most accurate. However, the pull-out strength test is simple, and the test result correlates well with adhesion work, which can be adopted daily to evaluate the fiber asphalt mastic interfacial properties.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
It is now more popular to use basalt fibers in the engineering programs to reinforce the crack resistance of asphalt mixtures. However, research concerning the impact of the basalt fiber diameter on ...the macro performance of AC-13 mixtures is very limited. Therefore, in this paper, basalt fibers with three diameters, including 7, 13 and 25 μm, were selected to research the influences of fiber diameter on the crack resistance of asphalt mixtures. Different types of crack tests, such as the low temperature trabecular bending test (LTTB), the indirect tensile asphalt cracking test (IDEAL-CT), and the semi-circular bend test (SCB), were conducted to reveal the crack resistance of AC-13 mixtures. The entire cracking process was recorded through the digital image correlation (DIC) technique, and the displacement cloud pictures, strain, average crack propagation rate (V) and fracture toughness (FT) indicators were used to evaluate the crack inhibition action of the fiber diameter on the mixture. The results showed that the incorporation of basalt fiber substantially improved the crack resistance, slowed down the increase of the displacement, and delayed the fracture time. Basalt fiber with a diameter of 7 μm presented the best enhancement capability on the crack resistance of the AC-13 mixture. The flexibility index (FI) of the SCB test showed a good correlation with V and FT values of DIC test results, respectively. These findings provide theoretical advice for the popularization and engineering application of basalt fibers in asphalt pavement.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This paper aims to analyze the interface property between fibers and asphalt, and study its influence on the crack resistance of the asphalt mixture. Four fibers (basalt fiber A (BF-A), basalt fiber ...B (BF-B), polyester fiber (PEF) and polyacrylonitrile fiber (PAF)) were selected in the study. The interface adhesion parameters were obtained by conducting the novel fiber-asphalt pullout test, and the micromorphology of the fiber-asphalt interface area was also observed. The crack resistance of the mixture was determined using the indirect tensile asphalt cracking test (IDEAL-CT) and the semi-circular bending test (SCB). Basic crack resistance indicators such as CTIndex and flexibility index (FI) were used for analyzing. Meanwhile, digital image correlation (DIC) technology was adopted to quantitatively characterize the crack inhibition mechanism of fibers in the fiber-asphalt mixtures. The results showed that the interface adhesion strength between BF-A and asphalt is the largest at 25 ℃, followed by BF-B, PEF and PAF. The addition of fibers can effectively improve the CTIndex and FI of asphalt mixtures, and it is found that the interface adhesion characteristics between fibers and asphalt have a great influence on the crack propagation process. The crack opening velocity curve obtained from the DIC analysis can quantitatively characterize the crack development law of the asphalt mixture. The coefficient of determination R2 between the interface adhesion strength and the DIC index (stage I velocity change rate and timing point 1 time) exceeded 0.85. The results can provide scientific references for the design and application of fiber reinforced asphalt mixture.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Diabetes is well recognized to increase the risk of heart failure, which is associated with higher mortality and morbidity. It is important for the development of novel therapeutic methods targeting ...heart failure in diabetic patients. Ferroptosis, an iron-dependent regulated cell death, has been implicated in the progression of diabetes-induced heart failure (DIHF). This study was designed to investigate the contribution of Nr2f2 to the activation of ferroptosis and mitochondrial dysfunction in DIHF. We established a diabetic model by a high-fat feeding diet combined with an intraperitoneal injection of streptozotocin. After 16 weeks, Nr2f2 expression was increased in heart tissue of DIHF mice. In vivo, DIHF mice overexpressing Nr2f2 (AAV9-cTNT-Nr2f2) exhibited severe heart failure and enhanced cardiac ferroptosis compared with DIHF control mice (AAV9-cTNT-ctrl), accompanied by mitochondrial dysfunction and aggravated oxidative stress reaction. In vitro, Nr2f2 knockdown ameliorated ferroptosis and mitochondrial dysfunction by negatively regulating PGC-1α, a crucial metabolic regulator. PGC-1α knockdown counteracted the protective effect of Nr2f2 knockdown. These data suggest that Nr2f2 promotes heart failure and ferroptosis in DIHF by modulating the PGC-1α signaling. Our study provides a new idea for the treatment of diabetes-induced heart failure.
Full text
Available for:
DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, SIK, UILJ, UKNU, UL, UM, UPUK
Our previous study indicated that interleukin (IL)-37 is involved in atherosclerosis. In the present study, Anterior tibial arteries were collected from diabetes patients and controls. A ...histopathological analysis showed that IL-37 was over-expressed in human atherosclerotic plaques. Many types of cells including macrophages, vascular smooth muscle cells (VSMCs), endothelial cells and T lymphocyte expressed IL-37 in human atherosclerotic plaques. ApoE-/- mice were divided into a control group and a recombinant human IL-37-treated group. The IL-37 treatment resulted in a significant decrease in macrophages and CD4+ T lymphocytes and a substantial increase in VSMCs and collagen in atherosclerotic plaques, resulting in a reduction in atherosclerotic plaque size. Furthermore, the IL-37 treatment modulated the CD4+ T lymphocyte activity, including a decrease in T helper cell type 1 (Th1) and Th17 cells and an increase in regulatory T (Treg) cells, and inhibited the maturity of dendritic cells both in vivo and in vitro. In addition, treatment with anti-IL-10 receptor monoclonal antibody abrogated the anti-atherosclerotic effects of IL-37. These data suggest that exogenous IL-37 ameliorates atherosclerosis via inducing the Treg response. IL-37 may be a novel therapeutic to prevent and treat atherosclerotic disease.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
A wide variety of polymer additives have been widely used in recent years. However, the effect of different polymer additives on the durability of asphalt binders has not been investigated ...thoroughly. To evaluate the aging property of styrene-butadiene-styrene (SBS) asphalt binder with different polymer additives, three polymer modifiers, namely high modulus modifier (HMM), anti-rutting agent (ARA), and high viscosity modifier (HVM), were added to it. First, the Thin Film Over Test (TFOT) and Pressure Aging Vessel (PAV) was performed on the asphalt binders. The rheological properties of the four asphalt binders before and after aging were then checked by the Dynamic Shear Rheometer Test (DSR). The chemical compositions of the asphalt binders were determined by the Fourier Transform Infrared Spectrometer (FTIR) test. Several aging indicators were adopted to reflect the aging degree of the asphalt binders. The results show that when polymer additives are added to the SBS asphalt binder, the complex modulus, storage modulus, loss modulus, and rutting factor substantially increase and the phase angle decreases. All the test parameters become higher after aging. The phase angle of the SBS asphalt binder is the highest at both unaged and aged states, while its other parameters values are the smallest. Moreover, the Carbonyl Aging Indicator (CAI) of SBS with polymer additives becomes lower under both TFOT and PAV conditions, indicating that polymer additives can improve the aging resistance of SBS asphalt, of which HVM modifies the aging resistance best. Complex Modulus Aging Indicator (CMAI) and Storage Modulus Aging Indicator (SMAI) have the best correlation coefficients with CAI, and the two aging indicators can be used to predict the aging degree of polymer modified asphalt binders.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
To evaluate the long-term performances of different polymer-modified asphalt mixtures, three modifiers were chosen to modify AC-13 (defined as the asphalt concrete with the aggregate nominal maximum ...particle size of 13.2 mm); namely, high viscosity modifier (HVM), high modulus modifier (HMM), and anti-rutting agent (ARA). The deformation and cracking resistance of different polymer-modified mixtures were checked at different aging conditions (unaged, short-term aged, and long-term aged for 5, 10, and 15 days respectively). The results of the Hamburg wheel-track test and uniaxial penetration test (UPT) showed that the rutting resistance of all asphalt mixtures changed in a V-shape as the aging progressed. From the unaged stage to the long-term aging stage (5 days), the rutting resistance decreases gradually. While after the long-term aging stage (5 days), the rutting resistance increases gradually. Results from the semicircular bending test (SCB) and the indirect tensile asphalt cracking test (IDEAL-CT) indicated that the cracking resistance of all the mixtures gradually decline with the deepening of the aging degree, indicating that aging weakens the crack resistance of asphalt mixtures. Additionally, test results showed that the rutting resistance of ARA AC-13 (defined as AC-13 containing ARA) is the best, the cracking resistances of ARA AC-13, HMM AC-13 (defined as AC-13 containing HMM) and HVM AC-13 (defined as AC-13 containing HVM) have no significant difference, and different polymer modifiers had different sensitivities to aging due to the polymer content and the type of modifier. The conclusions of this study help to further understand the long-term performance of polymer-modified asphalt mixtures during service life and to help guide the selection of modifiers for mixtures.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
This paper aims to better analyze the crack resistance of lignin fiber reinforced SMA-13 (LFSMA-13) asphalt mixtures, with and without polymer anti-rut agent (ARA), under different aging degrees. ...IDEAL-CT test and Fourier transform infrared (FTIR) spectroscopy were utilized to analyze the relationships between the crack resistance of LFSMA-13, with and without ARA, and the parameters of the FTIR spectrum of the asphalt extracted from the test samples. A convenient testing method to predict the anti-crack ability of the mixtures in a road was also derived in this study. The test samples were prepared using the specifications listed by AASHTO. The fracture formation work (Winitial) and cracking index (CTIndex) in the IDEAL-CT test were adopted to reflect the cracking ability of the asphalt mixtures in both the crack formation stage and the crack propagation stage. The peak areas of the FTIR spectrum were utilized to reveal the chemical properties of the asphalt material inside the SMA-13 asphalt mixtures, with and without ARA under different aging degrees. Grey correlation analysis was adopted to choose the most suitable FTIR spectrum parameters to derive the prediction models of Winitial and CTIndex under different aging degrees. After conducting a series of tests, the results showed that the aging process could well affect the crack resistance of the test samples and the peak areas of the asphalt extracted from the mixtures. The FTIR parameters selected from the grey correlation analysis could be used to well predict the anti-crack ability of the asphalt mixtures.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
PDF
