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Aim: To investigate the impact of high-dose of perindopril on cardiac function and ACE2/AT2R pathway in rabbits with ischemic cardiac dysfunction. Methods: The thirty rabbits with ischemic cardiac dysfunction were divided into high-dose group (Perindopril, 2 mg/kg/d), low-dose group (Perindopril, 0.66 mg/kg/d), and control groups (Saline, 2 ml/kg/d) by a random number table. After four weeks, we measured the cardiac function, The level of Ang-(1-7) and Ang-(1-9), mRNA expression level of ACE2 and AT2R. Results: The results showed that high dose and low dose of perindopril could improve cardiac function (p < 0.001), and high-dose perindopril had more significant improvement (p = 0.041). After treatment, in high-dose group, mRNA level of ACE2, AT2R in myocardium (p < 0.001) and Ang-(1-9) level in serum (p = 0.012) were higher than low-dose group, while Ang-(1-7) levels in serum didn’t show a significant difference (p = 0.829). LVEF and serum Ang-(1-9) were significantly correlated (p = 0.002), LVEF and ACE2 (p = 0.001), LVEF and AT2R (p = 0.007); however, it was no correlation between LVEF and serum Ang-(1-7) (p = 0.067). Conclusion: A high-dose of perindopril could improve ischemic cardiac dysfunction by ACE2/Ang-(1-9)/Ang-(1-7) pathway.

To study the clinical significance of miR-27a expression in serum exosomes in patients with heart failure (HF), this study was carried out. Totally 101 chronic heart failure (CHF) patients (research group) admitted to our hospital from April 2016 to January 2019 were enrolled, and another 30 healthy subjects (control group) who underwent physical examination during the same period were selected. The difference of miR-27a expression level in serum exosomes between the two groups of subjects was compared, so as to analyze the diagnostic value of miR-27a in CHF and the relationship between miR-27a expression level and patient prognosis. The expression level of miR-27a in peripheral blood exosomes of subjects in the control group (CG) was significantly higher than that in the research group (RG) (P

This study aimed to investigate the mechanism of how miR-362-3p/orosomucoid 1 (ORM1) involved in hypoxia/reoxygenation (H/R)-induced cardiomyocytes injury. Based on data obtained from Gene Expression Omnibus (GEO) database, we revealed that ORM1 was highly expressed and positively correlated with the expression of inflammatory factors (MAPK1, MAPK3, IL1B and CASP9). miR-362-3p was identified as an upstream regulatory miRNA of ORM1 and negatively modulated the mRNA and protein expression levels of ORM1 in H/R-injured cardiomyocytes. Moreover, we found that miR-362-3p was downregulated in cardiomyocytes injured by H/R. The promoting influence of miR-362-3p mimic on the proliferation and the inhibitory effect of miR-362-3p mimic on the apoptosis of H/R-stimulated cardiomyocytes were eliminated by overexpression of ORM1. Furthermore, miR-362-3p affected the expression of MAPK1, MAPK3, IL1B and CASP9 in H/R-injured cardiomyocytes through targeting ORM1. Our outcomes illustrated that miR-362-3p exhibited a protective influence on H/R-induced cardiomyocytes through targeting ORM1.

Triple-negative breast cancer (TNBC) is the most complex and challenging breast cancer subtype to treat, and chemotherapy remains the standard of care. Clinically, TNBC has a relatively high rate of recurrence and poor prognosis, which leads to a significant effort to discover novel strategies to treat patients with these tumors. Currently, chimeric antigen receptor (CAR) T cell-based immunotherapy redirects the patient's immune system directly to recognize and eradicate tumor-associated antigens (TAAs) expressing tumor cells being explored as a treatment for TNBC. A steadily increasing research in CAR T-cell therapy targeting different TAAs in TNBC has reported. In this review, we introduce the CAR technology and summarize the potential TAAs, available CARs, the antitumor activity, and the related toxicity of CARs currently under investigation for TNBC. We also highlight the potential strategies to prevent/reduce potential "on target, off tumor" toxicity induced by CAR T-cell therapy. This review will help to explore proper targets to expand further the CAR T-cell therapy for TNBCs in the clinic.

Solar PV is expected to become the most cost-competitive renewable energy owing to the rapidly decreasing cost of the system. On the other hand, hydropower is a high-quality and reliable regulating power source that can be bundled with solar PV to improve the economic feasibility of long-distance transmitted power. In this paper, a quantification model is established taking into account the regulating capacity of the reservoir, the characteristics of solar generation, and cost of hydro and solar PV with long-distance transmission based on the installed capacity ratio of hydro-solar hybrid power. Results indicate that for hydropower stations with high regulating capacity and generation factor of approximately 0.5, a hydro-solar installed capacity ratio of 1:1 will yield overall optimal economic performance, whereas for hydropower stations with daily regulating capacity reservoir and capacity factor of approximately 0.65, the optimal hydro-solar installed capacity ratio is approximately 1:0.3. In addition, the accuracy of the approach used in this study is verified through operation simulation of a hydro-solar hybrid system including ultra high-voltage direct current (UHVDC) transmission using two case studies in Africa. Keywords: Hydropower, Solar power, Multi-energy hybrid system, Economic analysis, UHVDC transmission, Hydro-solar Hybrid Power

Objective: To evaluate the protective role of valsartan in the myocardial injury of diabetic rats induced by herceptin. Method: 40 Sprague Dawley (SD) rats were randomly divided into control group and treatment group, 20 in each group. All the rats were faded with high sugar and high fat diet in 4 weeks, and then were given streptozotocin (STZ) by intraperitoneal injection in dose of 25mg/kg, fasting blood glucose (FBG) ≥ 16.7mmol/L as a standard of type 2 diabetes model. Two groups were given herceptin by intraperitoneal injection, 12mg/kg in the first day and then 6mg/kg in the following 6 days, but the treatment group was given valsartan by gavage before herceptin injection in dose of 10mg/kg one day, the control group was given the same dose of saline by gavage. The serum BNP were measured, echocardiogram was performed to evaluate the cardiac function before herceptin injection and after 4 weeks. Results: After 4 weeks the BNP, LVEDD, LVESD of the control group were larger than the treatment group, and the EF were smaller, and they were statistically different. Conclusion: Valsartan can alleviate myocardial injury diabetic rats induced by herceptin.

Metabolic remodeling contributes to the pathological process of heart failure (HF). We explored the effects of cardiac contractility modulation (CCM) on myocardial metabolic remodeling in the rabbit model with HF. The HF in rabbit model was established by pressure uploading and then CCM was applied. We evaluated the cardiac structure and function by echocardiography, serum BNP level, and hematoxylin and eosin and Masson’s trichrome staining. We detected the accumulation of glycogen and lipid droplets in myocardial tissues by periodic acid-Schiff and Oil Red O staining. Then, we measured the contents of glucose, free fatty acid (FFA), lactic acid, pyruvate, and adenosine triphosphate (ATP) levels in myocardial tissues by corresponding kits and the expression levels of key factors related to myocardial substrate uptake and utilization by western blotting were analyzed. CCM significantly restored the cardiac structure and function in the rabbit model with HF. CCM therapy further decreased the accumulation of glycogen and lipid droplets. Furthermore, CCM reduced the contents of FFA, glucose, and lactic acid, and increased pyruvate and ATP levels in HF tissues. The protein expression levels related to myocardial substrate uptake and utilization were markedly improved with CCM treatment by further activating adenosine monophosphate-activated protein kinase and peroxisome proliferator-activated receptor-α signaling pathways.

Background The benefit of thrombus aspiration (TA) during primary percutaneous coronary intervention (PPCI) to patients with ST-segment elevation myocardial infarction (STEMI) remains controversial. This study aimed to assess TA's impact on the outcome and prognosis for patients with STEMI and a large thrombus burden during PPCI. Methods This retrospective study evaluated consecutive patients with STEMI and a large thrombus burden (thrombolysis in myocardial infraction [TIMI] thrombus grade ≥4) who underwent conventional PPCI (n = 126) or PPCI + TA (n = 208) between February 2017 and January 2019. The procedure outcome and clinical prognosis were compared. Results Postprocedural vessel diameter was larger, and corrected TIMI frame count (cTFC) was lower in the PPCI + TA compared with the PPCI group. The proportion of postprocedural TIMI 3 flow was 83.3% in the PPC group and 94.2% in the PPCI+TA group. During the 12-month follow-up, no significant differences existed in the incidence of cardiac death, reinfarction, stent thrombosis, target vessel revascularization, or stroke. Conclusion Application of TA in patients with STEMI and a large thrombus burden during PPCI may improve the procedural outcome, but it showed no benefit on the clinical prognosis in the 12-month follow-up. Longer follow-up studies are needed to confirm TA's clinical implications in patients with STEMI.

Grating-box test is proposed and applied to evaluate the resisting ability of granular packs to the filling movement of self-compacting cementing materials. Firstly, parameter “ h 2 ” (“ h 2 N ”), reflecting the filling performance of SCM, is obtained from theoretical analysis of self-compacting-mortar’s filling performance in quasi-three-dimensional (quasi-3D) granular packs. Second, experimental results of grating-box test with quasi-3D molds using cylindrical obstacles are found in good agreement with the theoretical analysis above. Third, damping coefficient “ η ”, an indicator being positive correlated with the resisting ability of granular packs to filling movement of SCM, is found to represent the inherent properties of granular packs.

Rock-filled concrete (RFC), a new type of concrete that was developed mainly for large scale concrete construction, has a different casting process than conventional concrete: large rocks are piled into the formwork first, then self-compacting concrete (SCC) is poured in and fill the voids of the rock skeleton under gravity due to its high flowability. One of the key issues about RFC lies in its large interfaces between the SCC and rocks. In this paper, laboratory-scale model RFC consisting of coarse aggregates (simulating rocks) and cement grout (simulating SCC) was cast to simulate RFC in construction. The effects of different factors (aggregate size, rheology of cement grout, etc.) on the properties of the interfacial transition zone (ITZ) between cement paste and aggregates of model RFC were investigated using Backscatter Electron (BSE) and nanoindentation techniques. Furthermore, by comparing the results of BSE and nanoindentation at identical regions, the relationship between porosity and elastic modulus was found to agree well with empirical formulas, bridging the microstructure with the mechanical properties of concrete.

Rock-filled concrete (RFC) was developed in China mainly for large-scale concrete construction. The distinctive casting procedure of RFC makes it highly dependent on the filling capacity of self-compacting concrete (SCC). This study investigated two of the most controversial issues regarding RFC—the filling performance of SCC and the large interface between SCC and rocks. These issues were examined through an experimental setup designed to stimulate SCC flow in rock skeleton. The effects of different factors (aggregate size, yield stress, etc.) on the filling capacity of SCC and the properties of RFC were investigated on the basis of filling rate, cross-section porosity, and interface microstructure. Two clogging mechanisms were summarized from literature and used to explain the experimental results. The findings indicate that the interface microstructure of RFC greatly depends on the filling performance of SCC which is significantly affected by the size and condition of the large rocks.

This study investigated the effects of different casting procedures on compressive strength, water permeability, and interfacial transition zone (ITZ) porosity of rock-filled concrete (RFC). Mixes of concrete with the same proportions were cast using the self-compacting method (the casting procedure of RFC) and the vibration method (the casting procedure of normal concrete). A control group of concrete was prepared to reveal the effects of aggregate size. Compressive tests and water permeability tests were performed in accordance with the current codes. Scanning electron microscopy was used to calculate the porosity of the ITZ by processing the second electron and backscattered electron images of the ITZ. The findings indicate that the self-compacting method can improve compressive strength and particularly impermeability grade. Switching the vibration method to the self-compacting method also significantly reduces ITZ porosity, especially the ITZ porosity at the lateral surface of the aggregate.

China has been entitled the biggest supplier and largest market of renewable energy for the past few years. With One Belt and One Road initiative carrying on, the China's renewable energy industry is looking for opportunities across the world. Latin America, which has rich renewable energy resources and urge demand for a cleaner and more sustainable energy system, may become an important target market for China. The prospect and potential of renewable energy cooperation between China and Latin America are promising. In this paper, six Latin American nations of varied background were selected as study cases. Their nation profile, energy resources, power market, and energy development trends were analysed, and the cooperation prospect and potential between these nations and China in renewable energy sector were discussed. The results indicate that Argentina and Bolivia are most potential cooperation partners, and project development and equipment manufacturing of non-hydro renewable energy, along with power grid upgrading are the prioritized areas. In addition, recommendations and solutions addressing the issues and challenges incurred in the current bilateral energy cooperation between China and Latin American nations were proposed.