A Review of Sisal Fiber-Reinforced Geopolymers: Preparation, Microstructure, and Mechanical Properties.

The early strength of geopolymers (GPs) and their composites is higher, and the hardening speed is faster than that of ordinary cementitious materials. Due to their wide source of raw materials, low energy consumption in the production process, and lower emissions of pollutants, they are considered to have the most potential to replace ordinary Portland cement. However, similar to other inorganic materials, the GPs themselves have weak flexural and tensile strength and are sensitive to micro-cracks. Improving the toughness of GP materials can be achieved by adding an appropriate amount of fiber materials into the matrix. The use of discrete staple fibers shows great potential in improving the toughness of GPs. Sisal is a natural fiber that is reproducible and easy to obtain. Due to its good mechanical properties, low cost, and low carbon energy usage, sisal fiber (SF) is a GP composite reinforcement with potential development. In this paper, the research progress on the effect of SF on the properties of GP composites in recent decades is reviewed. It mainly includes the chemical composition and physical properties of SFs, the preparation technology of sisal-reinforced geopolymers (SFRGs), the microstructure analysis of the interface of SFs and the GP matrix, and the macroscopic mechanical properties of SFRGs. The properties of SFs make them have good bonding properties with the GP matrix. The addition of SFs can improve the flexural strength and tensile strength of GP composites, and SFRGs have good engineering application prospects.

Long Noncoding RNA Gpr137b-ps Promotes Advanced Atherosclerosis via the Regulation of Autophagy in Macrophages.

BACKGROUND: Current therapies cannot completely reverse advanced atherosclerosis. High levels of amino acids, induced by Western diet, stimulate mTORC1 (mammalian target of rapamycin complex 1)-autophagy defects in macrophages, accelerating atherosclerotic plaque progression. In addition, autophagy-lysosomal dysfunction contributes to plaque necrotic core enlargement and lipid accumulation. Therefore, it is essential to investigate the novel mechanism and molecules to reverse amino acid-mTORC1-autophagy signaling dysfunction in macrophages of patients with advanced atherosclerosis. METHODS: We observed that Gpr137b-ps (G-protein-coupled receptor 137B, pseudogene) was upregulated in advanced atherosclerotic plaques. The effect of Gpr137b-ps on the progression of atherosclerosis was studied by generating advanced plaques in ApoE-/- mice with cardiac-specific knockout of Gpr137b-ps. Bone marrow-derived macrophages and mouse mononuclear macrophage cell line RAW264.7 cells were subjected to starvation or amino acid stimulation to study amino acid-mTORC1-autophagy signaling. Using both gain- and loss-of-function approaches, we explored the mechanism of Gpr137b-ps-regulated autophagy. RESULTS: Our results demonstrated that Gpr137b-ps deficiency led to enhanced autophagy in macrophages and reduced atherosclerotic lesions, characterized by fewer necrotic cores and less lipid accumulation. Knockdown of Gpr137b-ps increased autophagy and prevented amino acid-induced mTORC1 signaling activation. As the downstream binding protein of Gpr137b-ps, HSC70 (heat shock cognate 70) rescued the impaired autophagy induced by Gpr137b-ps. Furthermore, Gpr137b-ps interfered with the HSC70 binding to G3BP (Ras GTPase-activating protein-binding protein), which tethers the TSC (tuberous sclerosis complex) complex to lysosomes and suppresses mTORC1 signaling. In addition to verifying that the NTF2 (nuclear transport factor 2) domain of G3BP binds to HSC70 by in vitro protein synthesis, we further demonstrated that HSC70 binds to the NTF2 domain of G3BP through its W90-F92 motif by using computational modeling. CONCLUSIONS: These findings reveal that Gpr137b-ps plays an essential role in the regulation of macrophage autophagy, which is crucial for the progression of advanced atherosclerosis. Gpr137b-ps impairs the interaction of HSC70 with G3BP to regulate amino acid-mTORC1-autophagy signaling, and these results provide a new potential therapeutic direction for the treatment of advanced atherosclerosis.

Establishment of a Novel Mouse Model for Atherosclerotic Vulnerable Plaque.

Background and Aims: Acute coronary syndrome (ACS) is a group of clinical syndromes characterized by rupture or erosion of atherosclerotic unstable plaques. Effective intervention for vulnerable plaques (VP) is of great significance to reduce adverse cardiovascular events. Methods: Fbn1C1039G+/- mice were crossbred with LDLR-/- mice to obtain a novel model for atherosclerotic VP. After the mice were fed with a high-fat diet (HFD) for 12 or 24 weeks, pathological staining and immunohistochemistry analyses were employed to evaluate atherosclerotic lesions. Results: Compared to control mice, Fbn1C1039G+/-LDLR-/- mice developed more severe atherosclerotic lesions, and the positive area of oil red O staining in the aortic sinus was significantly increased after 12 weeks (21.7 ± 2.0 vs. 6.3 ± 2.1) and 24 weeks (32.6 ± 2.5 vs. 18.7 ± 2.6) on a HFD. Additional vulnerable plaque characteristics, including significantly larger necrotic cores (280 ± 19 vs. 105 ± 7), thinner fiber caps (14.0 ± 2.8 vs. 32.6 ± 2.7), apparent elastin fiber fragmentation and vessel dilation (3,010 ± 67 vs. 1,465 ± 49), a 2-fold increase in macrophage number (8.5 ± 1.0 vs. 5.0 ± 0.6), obviously decreased smooth muscle cell number (0.6 ± 0.1 vs. 2.1 ± 0.2) and an ~25% decrease in total collagen content (33.6 ± 0.3 vs. 44.9 ± 9.1) were observed in Fbn1C1039G+/-LDLR-/- mice compared with control mice after 24 weeks. Furthermore, spontaneous plaque rupture, neovascularization, and intraplaque hemorrhage were detected in the model mouse plaque regions but not in those of the control mice. Conclusions: Plaques in Fbn1C1039G+/-LDLR-/- mice fed a HFD show many features of human advanced atherosclerotic unstable plaques. These results suggest that the Fbn1C1039G+/-LDLR-/- mouse is a novel model for investigating the pathological and physiological mechanisms of advanced atherosclerotic unstable plaques.

Differential RNA expression profiles and competing endogenous RNA-associated regulatory networks during the progression of atherosclerosis.

Aim: To identify differential mRNA and ncRNA expression profiles and competing endogenous RNA-associated regulatory networks during the progression of atherosclerosis (AS). Materials & methods: We systematically analyzed whole-transcriptome sequencing of samples from different stages of AS to evaluate their long noncoding RNA (lncRNA), circular RNA (circRNA), miRNA and mRNA profiles. Results: We constructed three AS-related competing endogenous RNA regulatory networks of differentially expressed circRNAs, lncRNAs, miRNAs and mRNAs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses revealed that the circRNAs in the network were enriched in lipid metabolic processes and participated in the PPAR signaling pathway. Furthermore, lncRNAs were related to receptor activity, myofibrils and cardiovascular system development. Conclusion: The current findings further clarified the regulatory mechanisms at different stages of AS and may provide new ideas and targets for AS.

Bioresorbable Scaffolds: Contemporary Status and Future Directions.

Percutaneous coronary intervention, which is safe, effective, and timely, has become an important treatment for coronary artery diseases and has been widely used in clinical practice. However, there are still some problems that urgently need to be solved. Permanent vessel caging through metallic implants not only prevents the process of positive vessel remodeling and the restoration of vascular physiology but also makes the future revascularization of target vessels more difficult. Bioresorbable scaffolds (BRSs) have been developed as a potential solution to avoid the above adverse reactions caused by permanent metallic devices. BRSs provide temporary support to the vessel wall in the short term and then gradually degrade over time to restore the natural state of coronary arteries. Nonetheless, long-term follow-up of large-scale trials has drawn considerable attention to the safety of BRSs, and the significantly increased risk of late scaffold thrombosis (ScT) limits its clinical application. In this review, we summarize the current status and clinical experiences of BRSs to understand the application prospects and limitations of these devices. In addition, we focus on ScT after implantation, as it is currently the primary drawback of BRS. We also analyze the causes of ScT and discuss improvements required to overcome this serious drawback and to move the field forward.

Incidence and Predictors of Neoatherosclerosis in Patients with Early In-Stent Restenosis Determined Using Optical Coherence Tomography.

In-stent restenosis (ISR) still exists after drug-eluting stent (DES) implantation, even up to one year. The incidence and risk factors for neoatherosclerosis in patients with early ISR have not yet been elucidated. Here, we used optical coherence tomography (OCT) to evaluate the incidence and predictors of neoatherosclerosis in patients with early ISRs.OCT was performed on ISR lesions in 185 patients in order to detect neoatherosclerosis. The median follow-up was 180 days, and neoatherosclerosis was detected in 37% of early ISR lesions. According to the presence of neoatherosclerosis, patients with ISR were divided into two groups: neoatherosclerosis (group A, n = 69) and non-neoatherosclerosis (group B, n = 116) groups.The risk factors were similar, except for hypercholesterolemia. Moreover, the tissue characteristics were not significantly different between patients with and without neoatherosclerosis. Follow-up low-density lipoprotein-cholesterol (LDL-C) levels were divided into three grades (LDL < 70 mg/dL, 70 mg/dL≤ LDL < 100 mg/dL, and LDL ≥ 100 mg/dL). The incidence of neoatherosclerosis was significantly lower (23% versus 57%, P < 0.0001) in the LDL < 70 mg/dL group. There was no significant difference in the incidence of neoatherosclerosis in patients with lipid levels between 70 and 100 mg/dL (P = 0.53). However, neoatherosclerosis was significantly more common in patients with a follow-up LDL-C level > 100 mg/dL (45% versus 15%, P < 0.0001).In patients with early ISR lesions, the LDL-C levels may be related to the formation and progression of early neoatherosclerosis, and poor LDL-C control may be a risk factor for the occurrence of early-stage neoatherosclerosis following DES implantation.

Macrophage-Enriched lncRNA RAPIA: A Novel Therapeutic Target for Atherosclerosis.

OBJECTIVE: Despite the current antiatherosclerotic and antithrombotic therapies, the incidence of advanced atherosclerosis-associated clinical events remains high. Whether long noncoding RNAs (lncRNAs) affect the progression of atherosclerosis and whether they are potential targets for the treatment of advanced atherosclerosis are poorly understood. Approach and Results: The progression of atherosclerotic lesions was accompanied by dynamic alterations in lncRNA expression, as revealed by RNA sequencing and quantitative polymerase chain reaction. Among the dynamically changing lncRNAs, we identified a novel lncRNA, lncRNA Associated with the Progression and Intervention of Atherosclerosis (RAPIA), that was highly expressed in advanced atherosclerotic lesions and in macrophages. Inhibition of RAPIA in vivo not only repressed the progression of atherosclerosis but also exerted atheroprotective effects similar to those of atorvastatin on advanced atherosclerotic plaques that had already formed. In vitro assays demonstrated that RAPIA promoted proliferation and reduced apoptosis of macrophages. A molecular sponge interaction between RAPIA and microRNA-183-5p was demonstrated by dual-luciferase reporter and RNA immunoprecipitation assays. Rescue assays indicated that RAPIA functioned at least in part by targeting the microRNA-183-5p/ITGB1 (integrin ß1) pathway in macrophages. In addition, the transcription factor FoxO1 (forkhead box O1) could bind to the RAPIA promoter region and facilitate the expression of RAPIA. CONCLUSIONS: The progression of atherosclerotic lesions was accompanied by dynamic changes in the expression of lncRNAs. Inhibition of the pivotal lncRNA RAPIA may be a novel preventive and therapeutic strategy for advanced atherosclerosis, especially in patients resistant or intolerant to statins.

[Effects of spraying salicylic acid and potassium dihydrogen phosphate on physiological cha-racteristics and grain yield of single-season rice under high temperature condition]. / é«˜æ¸©ä¸‹å–·æ–½æ°´æ¨é ¸å’Œç£·é ¸äºŒæ°¢é’¾å¯¹ä¸­ç¨»ç”Ÿç†ç‰¹å¾å’Œäº§é‡çš„å½±å“.

To explore new practical means of alleviating the negative effect of heat stress on rice plants during the heading-flowering stage, a field experiment was conducted in Ji'an, Yugan, and Nanchang counties of Jiangxi Province from 2017 to 2018 with three indica hybrid rice varieties. Under ambient high temperature condition during the heading-flowering period, we sprayed five concentrations of salicylic acid (SA) (SA1-SA5: 100, 500, 1000, 1500, 2000 µmol·L-1) and five concentrations of KH2PO4 (K1-K5: 7.35, 14.70, 22.05, 29.40, 36.75 mmol·L-1) on the leave of rice, with deionized water as the control (CK), to mesure the physiological characteristics and grain yield. The results showed that compared to CK,plants treated with SA and KH2PO4 had higher chlorophyll content, soluble sugar content, soluble protein content, proline content, supero-xide dismutase activity, and peroxidase activity, but a lower malonaldehyde content, among which SA2 and K3 treatments performed the best. The treatments of SA2, SA3, K3, and K4 increased the number of grains per panicle, seed-setting rate, and grain yield, with the effects of SA2 and K3 treatments being significant. Compared to CK, the SA2 treatments enhanced the number of grains per panicle, seed-setting rate, and grain yield by 7.0%, 4.0%, and 11.9%, respectively; the K3 treatments enhanced the number of grains per panicle, seed-setting rate, and grain yield by 3.9%, 4.7%, and 6.6%, respectively. The optimal measure was spraying 500 µmol·L-1 SA or 22.05 mmol·L-1 KH2PO4, which could significantly increase grain yield of single-season rice under high temperature condition during the heading-flowering period.

Modified balloon-stent kissing technique avoid side-branch compromise for simple true bifurcation lesions.

BACKGROUND: Coronary bifurcation remains one of the most challenging lesion subsets in interventinal cardiology. Provisional stenting (PS) is the dominate technique for bifurcation lesions, but the key problem is the deterioration of side branch. Balloon-stent kissing technique (BSKT) as a new systematic approach which is based on modified jailed balloon technique is applied to improve the procedure success. In our center, we proposed a modified balloon-stent kissing technique(M-BSKT), which routine usage of proximal optimizing technique (POT) after rewiring was added as an optimization step to BSKT. Thus, whether M-BSKT for addressing simple true coronary bifurcation lesions can provide more benefits in intra-operation effect and long term outcomes is still unknown. METHODS: A cohort of 120 consecutive patients underwent Percutaneous Coronary Intervention (PCI) with simple true coronary bifurcation lesions satisfied the criteria were included in this retrospective, single-center registry. To assemble a cohort with similar baseline characteristics, a 1:1 propensity-matched score was used. The primary outcomes were the rate of device and procedural success, the situation of side branch (SB) after main vessel (MV) inflation and the complications during intra-operative. The secondary outcomes were the clinical prognosis at 12 months such as rehospitalization for unstable angina and MACEs. RESULTS: Before propensity matching, there were no significant differences in primary and secondary outcomes between two groups. After propensity-matched was used, 68 patients with similar propensity scores were included. At immediate procedural, M-BSKT was associated with a lower risk of SB deterioration and the application of final kissing balloon inflation (FKBI)[P = 0.036]. For ACS patients, besides the significant differences of immediate SB deterioration [P = 0.014] and FKBI application [P = 0.033], the incidence of TIMI flow< 3 in the PS was statistically significant higher than M-BSKT [P= 0.042]. The prognosis at 12 months such as rehospitalization for unstable angina and MACEs were similar for two groups [P = 0.613]. CONCLUSION: These observations prove that the M-BSKT enables side branch to be better protected in simple true bifurcation lesions, by a narrow margin. It may improve the angiographic outcomes about side branch deterioration and final kissing balloon performing compared with PS, especially in ACS patients. However, long-term clinical outcomes did not differ between patients treated for M-BSKT and PS at 12 months.

Construction of a microRNA­associated feed­forward loop network that identifies regulators of cardiac hypertrophy and acute myocardial infarction.

Feed­forward loops (FFLs) are three­gene modules that exert significant effects on a series of biological processes and carcinogenesis development. MicroRNA­associated FFLs (miR­FFLs) represent a new era in disease research. However, analysis of the miR­FFL network motifs has yet to be systematically performed, and their potential role in cardiac hypertrophy and acute myocardial infarction (AMI) requires investigation. The present study used a computational method to establish a comprehensive miR­FFL network for cardiac hypertrophy and AMI, by integrating high­throughput data from different sources and performing multi­aspect analysis of the network features. Several heart disease­associated miR­FFL motifs were identified that were specific or common to the two diseases investigated. Functional analysis further revealed that miR­FFL motifs provided specific drug targets for the clinical treatment of cardiac hypertrophy and AMI. Associations between specific drugs associated with heart disease and dysregulated FFLs were also identified. The present study highlighted the components of FFL motifs in cardiac hypertrophy and AMI, and revealed their possibility as heart disease biomarkers and novel treatment targets.

Initial In Vivo Evaluation of a Novel Left Ventricular Assist Device.

The aim of the study was to use the ovine model to evaluate the hemocompatibility and end-organ effects of a newly developed magnetic suspension centrifugal left ventricular assist device (LVAD) by CH Biomedical Inc., Jiangsu, China. The LVADs were implanted in 6 healthy sheep, where inflow was inserted into the left ventricular apex and outflow was anastomosed to the descending aorta. All sheep received anticoagulation and antiaggregation therapy during the study. Hematologic and biochemical tests were performed to evaluate anemia, hepatorenal function, and the extent of hemolysis. The experiments lasted for up to 30 days on the beating hearts. All sheep were humanely killed at the termination of the experiments, and the end-organs were examined macroscopically and histopathologically. Autopsy was performed in all animals and there was no thrombus formation observed inside the pump. The pump's inflow and outflow conduits were also free of thrombus. Hematologic and biochemical test results were within normal limits during the study period. Postmortem examination of the explanted organs revealed no evidence of ischemia or infarction. Based on the in vivo study, this LVAD is suitable for implantation and can provide efficient support with good biocompatibility. The encouraging results in this study suggest that it is feasible to evaluate the device's long-term durability and stability.