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The transient receptor potential canonical (TRPC) channels have been implicated in various types of malignancies including gastric cancer (GC). However, the detailed mechanisms of TRPC channels underlying cell proliferation and apoptosis of GC cells remain largely unknown. Here, we report that TRPC3 was highly expressed in clinical GC specimens and correlated with GC malignant progression and poor prognosis. Forced expression of TRPC3 in GC cells enhanced both receptor-operated Ca2+ entry (ROCE) and store-operated Ca2+ entry (SOCE) and promoted the nuclear factor of activated T cell 2 (NFATc2) nuclear translocation by AKT/GSK-3β and CNB2 signaling. Pharmacological inhibition of TRPC3 or CRISPR/Cas9-mediated TRPC3 knockout effectively inhibited the growth of GC cells both in vitro and in vivo. These effects were reversible by the rescue of TRPC3 expression. Furthermore, we confirmed the role of TRPC3 and the ROCE-AKT/GSK3β-CNB2/NFATc2 signaling cascade in regulating cell cycle checkpoint, apoptosis cascade, and intracellular ROS production in GC. Overall, our findings suggest an oncogenic role of TRPC3 in GC and may highlight a potential target of TRPC3 for therapeutic intervention of GC and its malignant progression.

Chloride channels play an important role in regulating smooth muscle contraction and proliferation, and contribute to the enhanced constriction of pulmonary arteries (PAs) in pulmonary hypertension (PH). The intracellular Cl− concentration ([Cl−]i), tightly regulated by various Cl− transporters, determines the driving force for Cl− conductance, thereby the functional outcome of Cl− channel activation. This study characterizes for the first time the expression profile of Cl− transporters/exchangers in PA smooth muscle and provides the first evidence that the intracellular Cl− homeostasis is altered in PA smooth muscle cells (PASMCs) associated with chronic hypoxic PH (CHPH). Quantitative RT-PCR revealed that the endothelium-denuded intralobar PA of rats expressed Slc12a gene family-encoded Na-K-2Cl cotransporter 1 (NKCC1), K-Cl cotransporters (KCC) 1, 3, and 4, and Slc4a gene family-encoded Na+-independent and Na+-dependent Cl−/HCO3− exchangers. Exposure of rats to chronic hypoxia (10% O2, 3 wk) caused CHPH and selectively increased the expression of Cl−-accumulating NKCC1 and reduced the Cl−-extruding KCC4. The intracellular Cl− concentration ([Cl−]i) averaged at 45 mM and 47 mM in normoxic PASMCs as determined by fluorescent indicator MEQ and by gramicidin-perforated patch-clamp technique, respectively. The ([Cl−]i was increased by ∼10 mM in PASMCs of rats with CHPH. Future studies are warranted to further establish the hypothesis that the altered intracellular Cl− homeostasis contributes to the pathogenesis of CHPH.

Obesity increases levels of an adipocyte-produced hormone leptin, which activates the sympathetic nervous system leading to hypertension. We have recently reported that acute leptin infusion induces hypertension acting via the TRPM7 (transient receptor potential cation channel subfamily M member 7) cation channel in the carotid bodies. We hypothesize that this mechanism causes hypertension when leptin levels are elevated chronically as observed in diet-induced obesity. We have developed a novel extended release preparation, hydrogel, of a TRPM7 inhibitor FTY720, which was administered to the carotid body area bilaterally and compared with control hydrogel in (1) male lean C57BL/6J mice treated with subcutaneous infusions of leptin; (2) diet-induced obese male C57BL/6J with hyperleptinemia at baseline. In the experiment (3), diet-induced obese C57BL/6J mice, in which Trpm7 was silenced in the carotid body areas by transfection with Ad-Trpm7 shRNA , were compared with control mice transfected with Ad-CON-shRNA . All mice were implanted in the left femoral artery with telemetry before the experiments for continuous blood pressure monitoring. In lean mice, leptin increased 24 hours mean arterial pressure from 101.2±1.2 to 112±1.5 mm Hg; Trpm7 inhibitor abolished leptin-induced hypertension. Obese mice had elevated mean arterial pressure of 115.3±1.7 mm Hg, which was lowered by 8.7±1.0 mm Hg on week 2 after Trpm7 inhibitor treatment ( P Trpm7 shRNA decreased blood pressure from 119.0±2.2 to 109.6±1.4 mm Hg ( P shRNA had no effect. In conclusion, our study has shown that inhibition of TRPM7 in carotid bodies abolished leptin-induced hypertension in obese mice.

Background: Pulmonary arterial hypertension maintains rapid cell proliferation and vascular remodeling through metabolic reprogramming. Recent studies suggested that circRNAs play important role in pulmonary vascular remodeling and pulmonary arterial smooth muscle cells proliferation. However, the relationship between circRNA, cell proliferation, and metabolic reprogramming in pulmonary arterial hypertension has not been investigated. Methods: RNA-seq and qRT-PCR reveal the differential expression profile of circRNA in pulmonary arteries of pulmonary arterial hypertension rat models. Transfection was used to examine the effects of circSMOC1 on pulmonary artery smooth muscle cells, and the roles of circSMOC1 in vivo were investigated by adenoassociated virus. Mass spectrometry, RNA pull-down, RNA immunoprecipitation, and dual-luciferase reporter assay were performed to investigate the signaling pathway of circSMOC1 regulating the metabolic reprogramming. Results: CircSMOC1 was significantly downregulated in pulmonary arteries of pulmonary arterial hypertension rats. CircSMOC1 knockdown promoted proliferation and migration and enhanced aerobic glycolysis of pulmonary artery smooth muscle cells. CircSMOC1 overexpression in vivo alleviates pulmonary vascular remodeling, right ventricular pressure, and right heart hypertrophy. In the nucleus, circSMOC1 directly binds to PTBP1 (polypyrimidine tract-binding protein), competitively inhibits the specific splicing of PKM (pyruvate kinase M) premRNA, resulting in the upregulation of PKM2 (pyruvate kinase M2), the key enzyme of aerobic glycolysis, to enhance glycolysis. In the cytoplasm, circSMOC1 acted as a miR-329-3p sponge, and its reduction in pulmonary arterial hypertension suppressed PDHB (pyruvate dehydrogenase E1 subunit beta) expression, leading to the impairment of mitochondrial oxidative phosphorylation. Conclusions: circSMOC1 is crucially involved in the metabolic reprogramming of pulmonary artery smooth muscle cells through PTBP1 and miR-329-3p to regulate pulmonary vascular remodeling in pulmonary arterial hypertension.

A topologically heterogeneous microstructure design is introduced in a Cu/Zr nanolayered composite, in which each soft 100 nm Cu or Zr layer is surrounded on both sides by several hard 10 nm Cu/Zr bilayers. This design aims to impose a full geometrical constraint on all of the soft layers. Micropillar compression tests demonstrate that the composite deforms in a compatible fashion among the layers, in which no extrusion of the soft layers occurs. An elevated strength of 730 MPa is achieved in the composite compared with the strength prediction based on the linear rule of mixtures.

Transient receptor potential vanilloid 4 (TRPV4) is a multi-functional non-selective channel expressed in pulmonary vasculatures. TRPV4 contributes to serotonin- (5-HT-) induced pulmonary vasoconstriction and is responsible in part for the enhanced 5-HT response in pulmonary arteries (PAs) of chronic hypoxia mice. Epoxyeicosatrienoic acid (EET) is an endogenous agonist of TRPV4 and is known to regulate vasoreactivity. The levels of EETs, the expression of cytochrome P450 (CYP) epoxygenase for EET production, and epoxide hydrolase for EET degradation are altered by chronic hypoxia. Here, we examined the role of EET-dependent TRPV4 activation in the 5-HT-mediated PA contraction. In PAs of normoxic mice, inhibition of TRPV4 with a specific inhibitor HC-067047 caused a decrease in the sensitivity of 5-HT-induced PA contraction without affecting the maximal contractile response. Application of the cytochrome P450 epoxygenase inhibitor MS-PPOH had no effect on the vasoreactivity to 5-HT. In contrast, inhibition of CYP epoxygenase or TRPV4 both attenuated the 5-HT-elicited maximal contraction to a comparable level in PAs of chronic hypoxic mice. Moreover, the inhibitory effect of MS-PPOH on the 5-HT-induced contraction was obliterated in PAs of chronic hypoxic trpv4-/- mice. These results suggest that TRPV4 contributes to the enhanced 5-HT-induced vasoconstriction in chronic hypoxic PAs, in part via the CYP-EET-TRPV4 pathway. Our results further support the notion that manipulation of TRPV4 function may offer a novel therapeutic strategy for the treatment of hypoxia-related pulmonary hypertension.

Aims\ud \ud Restoration of myocardial blood flow and perfusion during percutaneous coronary intervention (PCI) measured using Thrombolysis in Myocardial Infarction (TIMI) flow grade (TFG) and perfusion grade (TMPG) is associated with improved outcomes in acute coronary syndrome (ACS). Associations between TFG/TMPG and changes in biomarkers reflecting myocardial damage/dysfunction and inflammation is unknown.\ud \ud \ud \ud Methods and results\ud \ud Among 2606 patients included, TFG was evaluated in 2198 and TMPG in 1874 with ST-segment elevation myocardial infarction (STEMI) or non-ST-segment ACS (NSTE-ACS). Biomarkers reflecting myocardial necrosis [troponin T (TnT)], myocardial dysfunction [N-terminal prohormone brain natriuretic peptide (NT-proBNP)], inflammation [interleukin-6 (IL-6) and C-reactive protein (CRP)], and oxidative stress/ageing/inflammation [growth differentiation factor-15 (GDF-15)] were measured at baseline, discharge, and 1- and 6-month post-randomization. Associations between TFG/TMPG and changes in biomarker levels were evaluated using the Mann–Whitney–Wilcoxon signed test. In total, 1423 (54.6%) patients had STEMI and 1183 (45.4%) NSTE-ACS. Complete reperfusion after PCI with TFG = 3 was achieved in 1110 (85.3%) with STEMI and in 793 (88.5%) with NSTE-ACS. Normal myocardial perfusion with TMPG = 3 was achieved in 475 (41.6%) with STEMI and in 396 (54.0%) with NSTE-ACS. Levels of TnT, NT-proBNP, IL-6, CRP, and GDF-15 were substantially lower at discharge in patients with complete vs. incomplete TFG and STEMI (P < 0.01). This pattern was not observed for patients with NSTE-ACS. Patients with normal vs. abnormal TMPG and NSTE-ACS had lower levels of NT-proBNP at discharge (P = 0.01).\ud \ud \ud \ud Conclusions\ud \ud Successful restoration of epicardial blood flow in STEMI was associated with less myocardial necrosis/dysfunction and inflammation. Attainment of normal myocardial perfusion was associated with less myocardial dysfunction in NSTE-ACS.

MAX phases have great potential under demands of both high-temperature and high-stress performance, with their mixed atomic bonding producing the temperature and oxidation resistance of ceramics with the mechanical resilience of metals. Here, we measure the mechanical properties up to 980C by nanoindentation on highly dense and pure Cr$_2$AlC, as well as after oxidation with a burner rig at 1200C for more than 29 hours. Only modest reductions in both hardness and modulus up to 980C were observed, implying no change in deformation mechanism. Furthermore, micro-cantilever fracture tests were carried out at the Cr$_2$AlC/Cr$_7$C$_3$ and Cr$_7$C$_3$/Al$_2$O$_3$ interfaces after the oxidation of the Cr$_2$AlC substrates with said burner rig. The values are typical of ceramic-ceramic interfaces, below 4 MPa/m, leading to the hypothesis that the excellent macroscopic behaviour is due to a combination of low internal strain due to the match in thermal expansion coefficient as well as the convoluted interface.

Molybdenum disilicide (MoSi$_2$) is a very promising material for high temperature structural applications due to its high melting point (2030 {\deg}C), low density, high thermal conductivity and good oxidation resistance. However, MoSi$_2$ has limited ductility below 900 {\deg}C due to its anisotropic plastic deformation behaviour and high critical resolved shear stresses on particular slip systems. Nanoindentation of MoSi$_2$ microalloyed with aluminium, niobium or tantalum showed that all alloying elements cause a decrease in hardness. Analysis of surface slip lines indicated the activation of the additional {1 1 0} slip system in microalloyed MoSi$_2$, which is not active below 300 {\deg}C in pure MoSi$_2$. This was confirmed by TEM dislocation analysis of the indentation plastic zone. Further micropillar compression experiments comparing pure MoSi$_2$ and the Ta-alloyed sample enabled the determination of the critical resolved shear stresses of individual slip systems even in the most brittle [0 0 1] crystal direction.

Background Uterine serous cancer (USC) is the most common non-endometrioid subtype of uterine cancer, and is also the most aggressive. Most patients will die of progressively chemotherapy-resistant disease, and the development of new therapies that can target USC remains a major unmet clinical need. This study sought to determine the molecular mechanism by which a novel unfavorable prognostic biomarker RYR1 identified in advanced USC confers their malignant phenotypes, and demonstrated the efficacy of targeting RYR1 by repositioned FDA-approved compounds in USC treatment. Methods TCGA USC dataset was analyzed to identify top genes that are associated with patient survival and can be targeted by FDA-approved compounds. The top gene RYR1 was selected and the functional role of RYR1 in USC progression was determined by silencing and over-expressing RYR1 in USC cells in vitro and in vivo. The molecular mechanism and signaling networks associated with the functional role of RYR1 in USC progression were determined by reverse phase protein arrays (RPPA), Western blot, and transcriptomic profiling analyses. The efficacy of the repositioned compound dantrolene on USC progression was determined using both in vitro and in vivo models. Results High expression level of ryanodine receptor 1 (RYR1) in the tumors is associated with shortened overall survival. Inhibition of RYR1 suppressed proliferation, migration and enhanced apoptosis through the Ca2+-dependent AKT/CREB/PGC-1α and AKT/HK1/2 signaling pathways, which modulate mitochondrial bioenergetics properties, including oxidative phosphorylation, ATP production, mitochondrial membrane potential, ROS production and TCA metabolites, and glycolytic activities in USC cells. Repositioned compound dantrolene suppressed USC progression in both in vitro and mouse models. Conclusions These findings provide insight into the mechanism by which RYR1 modulates the malignant phenotypes of USC and could aid in the development of dantrolene as a repurposed therapeutic agent for the treatment of USC to improve patient survival.

Intermetallic phases, such as Mg2Ca, have been shown to significantly improve the creep strength of magnesium alloys. However, the relevant deformation mechanisms of the intermetallics for further alloy development are largely unknown as the application temperature of the intermetallic-metallic composites lies in their brittle low temperature regime. In this study, we investigated the deformation mechanisms of the hexagonal Mg2Ca Laves phase at the same size scale (μm) as in intermetallic-metallic alloys and at room temperature using nanomechanical test methods. We identified active slip planes by a statistical evaluation of slip traces formed around nanoindentations and measured the corresponding critical resolved shear stresses for each slip system by compression of single crystalline micropillars in selected orientations. Deformation occurs on basal, 1st and 2nd order pyramidal as well as 1st and 2nd order prismatic planes and the critical stresses are of the order of 0.44 GPa–0.59 GPa with the lowest value obtained on the 1st order prismatic planes. Finally, we discuss the possible slip systems on a theoretical basis in terms of their local atomic structure.

The behaviour of many materials is strongly influenced by the mechanical properties of hard phases, present either from deliberate introduction for reinforcement or as deleterious precipitates. While it is, therefore, self-evident that these phases should be studied, the ability to do so&mdash, particularly their plasticity&mdash, is hindered by their small sizes and lack of bulk ductility at room temperature. Many researchers have, therefore, turned to small-scale testing in order to suppress brittle fracture and study the deformation mechanisms of complex crystal structures. To characterise the plasticity of a hard and potentially anisotropic crystal, several steps and different nanomechanical testing techniques are involved, in particular nanoindentation and microcompression. The mechanical data can only be interpreted based on imaging and orientation measurements by electron microscopy. Here, we provide a tutorial to guide the collection, analysis, and interpretation of data on plasticity in hard crystals. We provide code collated in our group to help new researchers to analyse their data efficiently from the start. As part of the tutorial, we show how the slip systems and deformation mechanisms in intermetallics such as the Fe7Mo6 &mu, phase are discovered, where the large and complex crystal structure precludes determining a priori even the slip planes in these phases. By comparison with other works in the literature, we also aim to identify &ldquo, best practises&rdquo, for researchers throughout to aid in the application of the methods to other materials systems.

Materialia 20, 101237 (2021). doi:10.1016/j.mtla.2021.101237, Published by Elsevier, Amsterdam

Characteristic densification in cold sintered microstructures could also have a strong influence in defining their mechanical response. For the first time, nanoindentation and micro-pillar testing is used to study these details. Based on our recent work, we selected cold sintered (250 °C, ∼ 99 % dense) and conventionally sintered (900 °C, ∼ 98 % dense) ZnO samples. Hardness, elastic modulus and compressive stress of cold sintered samples were measured to be 5.5 GPa ± 0.5, 100 GPa ± 5 and ∼ 1.2 GPa, respectively. Same values for conventionally sintered ZnO were 4.8 GPa ± 0.6, 109 GPa ± 6 and 0.8 GPa, respectively. The distinctive nature of grain boundary regions in cold sintered samples were found to influence the deformation behavior of these samples, as confirmed by TEM investigations. Our study reveals the potential of cold sintering and use of selected testing techniques as suitable choice.