CRIP1 regulates osteogenic differentiation of bone marrow stromal cells and pre-osteoblasts via the Wnt signaling pathway.

With the aging of the global demographic, the prevention and treatment of osteoporosis are becoming crucial issues. The gradual loss of self-renewal and osteogenic differentiation capabilities in bone marrow stromal cells (BMSCs) is one of the key factors contributing to osteoporosis. To explore the regulatory mechanisms of BMSCs differentiation, we collected bone marrow cells of femoral heads from patients undergoing total hip arthroplasty for single-cell RNA sequencing analysis. Single-cell RNA sequencing revealed significantly reduced CRIP1 (Cysteine-Rich Intestinal Protein 1) expression and osteogenic capacity in the BMSCs of osteoporosis patients compared to non-osteoporosis group. CRIP1 is a gene that encodes a member of the LIM/double zinc finger protein family, which is involved in the regulation of various cellular processes including cell growth, development, and differentiation. CRIP1 knockdown resulted in decreased alkaline phosphatase activity, mineralization and expression of osteogenic markers, indicating impaired osteogenic differentiation. Conversely, CRIP1 overexpression, both in vitro and in vivo, enhanced osteogenic differentiation and rescued bone mass reduction in ovariectomy-induced osteoporosis mice model. The study further established CRIP1's modulation of osteogenesis through the Wnt signaling pathway, suggesting that targeting CRIP1 could offer a novel approach for osteoporosis treatment by promoting bone formation and preventing bone loss.

Propofol Causes Sustained Ca2+ Elevation in Endothelial Cells by Stimulating Ryanodine Receptor and Suppressing Plasmalemmal Ca2+ Pump.

ABSTRACT: Propofol, a general anesthetic administered intravenously, may cause pain at the injection site. The pain is in part due to irritation of vascular endothelial cells. We here investigated the effects of propofol on Ca2+ transport and pain mediator release in human umbilical vein endothelial cells (EA.hy926). Propofol mobilized Ca2+ from cyclopiazonic acid (CPA)-dischargeable pool but did not cause Ca2+ release from the lysosomal Ca2+ stores. Propofol-elicited Ca2+ release was suppressed by 100 µM ryanodine, suggesting the participation of ryanodine receptor channels. Propofol did not affect ATP-triggered Ca2+ release but abolished the Ca2+ influx triggered by ATP; in addition, propofol also suppressed store-operated Ca2+ entry elicited by CPA. Ca2+ clearance during CPA-induced Ca2+ discharge was unaffected by a low Na+ (50 mM) extracellular solution, but strongly suppressed by 5 mM La3+ (an inhibitor of plasmalemmal Ca2+ pump), suggesting Ca2+ extrusion was predominantly through the plasmalemmal Ca2+ pump. Propofol mimicked the effect of La3+ in suppressing Ca2+ clearance. Propofol also stimulated release of pain mediators, namely, reactive oxygen species and bradykinin. Our data suggest propofol elicited Ca2+ release and repressed Ca2+ clearance, causing a sustained cytosolic [Ca2+]i elevation. The latter may cause reactive oxygen species and bradykinin release, resulting in pain.

Sensitivity of Ca2+-sensing receptor-transient receptor potential-mediated Ca2+ influx to extracellular acidity in bEND.3 endothelial cells.

Ca2+-sensing receptors (CaSRs) are G protein-coupled receptors activated by elevated concentrations of extracellular Ca2+. In our previous works, we showed protein and functional expression of CaSR in mouse cerebral endothelial cell (EC) (bEND.3); the CaSR response (high Ca2+-elicited cytosolic [Ca2+] elevation) was unaffected by suppression of phospholipase C but in part involved Ca2+ influx through transient receptor potential V1 (TRPV1) channels. In this work, we investigated if extracellular acidity affected CaSR-mediated Ca2+ influx triggered by high (3 mM) Ca2+ (CaSR agonist), 3 mM spermine (CaSR agonist), and 10 mM cinacalcet (positive allosteric modulator of CaSR). Extracellular acidosis (pH 6.8 and pH 6.0) strongly suppressed cytosolic [Ca2+] elevation triggered by high Ca2+, spermine, and cinacalcet; acidosis also inhibited Mn2+ influx stimulated by high Ca2+ and cinacalcet. Purinoceptor-triggered Ca2+ response, however, was not suppressed by acidosis. Extracellular acidity also did not affect membrane potential, suggesting suppressed CaSR-mediated Ca2+ influx in acidity did not result from the reduced electrical driving force for Ca2+. Our results suggest Ca2+ influx through a putative CaSR-TRP complex in bEND.3 EC was sensitive to extracellular pH.

Trilinolein, a Natural Triacylglycerol, Protects Cerebral Ischemia through Inhibition of Neuronal Apoptosis and Ameliorates Intimal Hyperplasia via Attenuation of Migration and Modulation of Matrix Metalloproteinase-2 and RAS/MEK/ERK Signaling Pathway in VSMCs.

Cerebrovascular disease is one of the leading causes of disability and death worldwide, and seeking a potential treatment is essential. Trilinolein (TriL) is a natural triacylglycerol presented in several plants. The effects of TriL on cerebrovascular diseases such as cerebral ischemia and carotid stenosis have never been studied. Accordingly, we investigated the protection of TriL on cerebral ischemia/reperfusion (I/R) and vascular smooth muscle cell (VSMC) migration in vivo and in vitro. The cerebral infarction area, the intima to media area (I/M ratio), and proliferating cell nuclear antigen (PCNA)-staining of the carotid artery were measured. Platelet-derived growth factor (PDGF)-BB-stimulated A7r5 cell migration and potential mechanisms of TriL were investigated by wound healing, transwell, and Western blotting. TriL (50, 100, and 200 mg/kg, p.o.) reduced: the cerebral infarction area; neurological deficit; TUNEL-positive apoptosis; intimal hyperplasia; and PCNA-positive cells in rodents. TriL (5, 10, and 20 µM) significantly inhibited PDGF-BB-stimulated A7r5 cell migration and reduced matrix metalloproteinase-2 (MMP-2), Ras, MEK, and p-ERK protein levels in PDGF-BB-stimulated A7r5 cells. TriL is protective in models of I/R-induced brain injury, carotid artery ligation-induced intimal hyperplasia, and VSMC migration both in vivo and in vitro. TriL could be potentially efficacious in preventing cerebral ischemia and cerebrovascular diseases.

Strain-driven phase transition and spin polarization of Re-doped transition-metal dichalcogenides.

Two-dimensional transition metal dichalcogenides (TMDCs) are promising in spintronics due to their spin-orbit coupling, but their intrinsic non-magnetic properties limit their further development. Here, we focus on the energy landscapes of TMDC (MX2, M = Mo, W and X = S, Se, Te) monolayers by rhenium (Re) substitution doping under axial strains, which controllably drive 1H ↔ 1Td structural transformations. For both 1H and 1Td phases without strain, Re-doped TMDCs have an n-type character and are non-magnetic, but the tensile strain could effectively induce and modulate the magnetism. Specifically, 1H-Re0.5Mo0.5S2 gets a maximum magnetic moment of 0.69 µB at a 6% uniaxial tensile strain along the armchair direction; along the zigzag direction it exhibits a significant magnetic moment (0.49 µB) at a 2.04% uniaxial tensile strain but then exhibits no magnetism in the range of [5.10%, 7.14%]. By contrast, for 1Td-Re0.5Mo0.5S2 a critical uniaxial tensile strain along the zigzag direction reaches up to ∼9.18%, and a smaller uniaxial tensile strain (∼5.10%) along the zigzag direction is needed to induce the magnetism in 1Td-Re0.5M0.5Te2. The results reveal that the magnetism of Re-doped TMDCs could be effectively induced and modulated by the tensile strain, suggesting that strain engineering could have significant applications in doped TMDCs.

A basal level of γ-linolenic acid depletes Ca2+ stores and induces endoplasmic reticulum and oxidative stresses to cause death of breast cancer BT-474 cells.

Gamma-linolenic acid (GLA), a natural fatty acid obtained from oils of various vegetables and seeds, has been demonstrated as an anticancer agent. In this work, we investigated the anticancer effects of GLA on breast cancer BT-474 cells. GLA at 30 µM, a concentration reportedly within the range of circulating concentrations in clinical studies, caused apoptotic cell death. GLA caused an elevation in mitochondrial Ca2+ level and a decrease in mitochondrial membrane potential. GLA treatment depleted cyclopiazonic acid (CPA)-sensitive Ca2+ store and triggered substantial Ca2+ influx. Intracellular Ca2+ release triggered by GLA was suppressed by 3 µM xestospongin C (XeC, IP3 receptor-channel blocker) and 100 µM ryanodine (ryanodine receptor-channel blocker), suggesting that the Ca2+ release was via IP3 receptor-channel and ryanodine receptor-channel. Increased expressions of p-eIF2α and CHOP were observed in GLA-treated cells, suggesting GLA-treated cells had increased expressions of p-eIF2α and CHOP, which suggest endoplasmic reticulum (ER) stress. In addition, GLA elicited increased production of reactive oxygen species. Taken together, our results suggest a basal level of GLA induced apoptotic cell death by causing Ca2+ overload, mitochondrial dysfunction, Ca2+ store depletion, ER stress, and oxidative stress. This is the first report to show that GLA caused Ca2+ store depletion and ER stress. GLA-induced Ca2+ store depletion resulted from opening of IP3 receptor-channel and ryanodine receptor-channel.

Characterization of Ca2+-Sensing Receptor-Mediated Ca2+ Influx in Microvascular bEND.3 Endothelial Cells.

Ca2+-sensing receptors (CaSR), activated by elevated concentrations of extracellular Ca2+, have been known to regulate functions of thyroid cells, neurons, and endothelial cells (EC). In this report, we studied CaSR-mediated Ca2+ influx in mouse cerebral microvascular EC (bEND.3 cells). Cytosolic free Ca2+ concentration and Mn2+ influx were measured by fura-2 microfluorometry. High (3 mM) Ca2+ (CaSR agonist), 3 mM spermine (CaSR agonist), and 10 µM cinacalcet (positive allosteric modulator of CaSR) all triggered Ca2+ influx; however, spermine, unlike high Ca2+ and cinacalcet, did not promote Mn2+ influx and its response was poorly sensitive to SKF 96365, a TRP channel blocker. Consistently, 2-aminoethoxydiphenyl borate and ruthenium red (two other general TRP channel blockers) suppressed Ca2+ influx triggered by cinacalcet and high Ca2+ but not by spermine. Ca2+ influx triggered by high Ca2+, spermine, and cinacalcet was similarly suppressed by A784168, a potent and selective TRPV1 antagonist. Our results suggest that CaSR activation triggered Ca2+ influx via TRPV1 channels; intriguingly, pharmacological, and permeability properties of such Ca2+ influx depended on the stimulating ligands.

Tannic acid, a vasodilator present in wines and beverages, stimulates Ca2+ influx via TRP channels in bEND.3 endothelial cells.

Tannic acid (TA) is a polyphenol compound present in wines and many beverages. Although previous works have shown that TA could cause vasodilation in an endothelial cell (EC)-dependent manner, there is hitherto no report showing whether TA could raise EC cytosolic Ca2+ concentration. In this work we examined the effects of TA on cytosolic Ca2+ of mouse brain bEND.3 EC. TA (1-30 µM) caused a slow elevation in cytosolic Ca2+ level in a concentration-dependent manner. At 30 µM, TA triggered Ca2+ influx without causing intracellular Ca2+ release. TA-triggered Ca2+ influx was suppressed by Ni2+ (a non-specific Ca2+ channel blocker), ruthenium red and SKF 96365 (non-specific TRP channel blockers), CBA (a selective TRPM4 inhibitor) and M 084 (a selective TRPC4/C5 blocker). However, TA-triggered Ca2+ influx pathway was not permeable to Mn2+. Our results suggest TA activated TRP channels, possibly TRPM4 and TRPC4/C5, to promote influx of Ca2+.

C1206, a novel curcumin derivative, potently inhibits Hsp90 and human chronic myeloid leukemia cells in vitro.

4-(4-Pyridinyl methylene) curcumin (C1206) is a new derivative of curcumin that is more active than curcumin in inhibition of heat shock protein 90 (Hsp90) and antitumor action. In this study we investigated the relationship between C1206-induced inhibition of Hsp90 and its anti-leukemic effects. The fluorescence quenching experiments showed that C1206 seemed to bind the middle dimerization domain of Hsp90. The interaction between C1206 and Hsp90 was driven mainly by electrostatic interaction. In in vitro enzyme activity assay, C1206 dose-dependently inhibited Hsp90 ATPase activity with an IC50 value of 4.17 µmol/L. In both imatinib-sensitive K562 chronic myeloid leukemia cells and imatinib-resistant K562/G01 chronic myeloid leukemia cells, C1206 (0.4-3.2 µmol/L) dose-dependently caused the degradation of Hsp90 client proteins and downstream proteins (AKT, MEK, ERK, C-RAF, P-AKT, P-MEK and P-ERK). Furthermore, C1206 (0.4-3.2 µmol/L) dose-dependently induced apoptosis of K562 and K562/G01 cells through triggering mitochondrial pathway. Consistent with this result, C1206 inhibited the proliferation of K562 and K562/G01 cells with IC50 values of 1.10 and 0.60 µmol/L, respectively. These results suggest that C1206 is a novel Hsp90 inhibitor and a promising therapeutic agent for chronic myeloid leukemia.

Vibsanin B preferentially targets HSP90ß, inhibits interstitial leukocyte migration, and ameliorates experimental autoimmune encephalomyelitis.

Interstitial leukocyte migration plays a critical role in inflammation and offers a therapeutic target for treating inflammation-associated diseases such as multiple sclerosis. Identifying small molecules to inhibit undesired leukocyte migration provides promise for the treatment of these disorders. In this study, we identified vibsanin B, a novel macrocyclic diterpenoid isolated from Viburnum odoratissimum Ker-Gawl, that inhibited zebrafish interstitial leukocyte migration using a transgenic zebrafish line (TG:zlyz-enhanced GFP). We found that vibsanin B preferentially binds to heat shock protein (HSP)90ß. At the molecular level, inactivation of HSP90 can mimic vibsanin B's effect of inhibiting interstitial leukocyte migration. Furthermore, we demonstrated that vibsanin B ameliorates experimental autoimmune encephalomyelitis in mice with pathological manifestation of decreased leukocyte infiltration into their CNS. In summary, vibsanin B is a novel lead compound that preferentially targets HSP90ß and inhibits interstitial leukocyte migration, offering a promising drug lead for treating inflammation-associated diseases.

Apelin: an endogenous peptide essential for cardiomyogenic differentiation of mesenchymal stem cells via activating extracellular signal-regulated kinase 1/2 and 5.

Growing evidence has shown that apelin/APJ system functions as a critical mediator of cardiac development as well as cardiovascular function. Here, we investigated the role of apelin in the cardiomyogenic differentiation of mesenchymal stem cells derived from Wharton's jelly of human umbilical cord in vitro. In this research, we used RNA interference methodology and gene transfection technique to regulate the expression of apelin in Wharton's jelly-derived mesenchymal stem cells and induced cells with a effective cardiac differentiation protocol including 5-azacytidine and bFGF. Four weeks after induction, induced cells assumed a stick-like morphology and myotube-like structures except apelin-silenced cells and the control group. The silencing expression of apelin in Wharton's jelly-derived mesenchymal stem cells decreased the expression of several critical cardiac progenitor transcription factors (Mesp1, Mef2c, NKX2.5) and cardiac phenotypes (cardiac α-actin, ß-MHC, cTnT, and connexin-43). Meanwhile, endogenous compensation of apelin contributed to differentiating into cells with characteristics of cardiomyocytes in vitro. Further experiment showed that exogenous apelin peptide rescued the cardiomyogenic differentiation of apelin-silenced mesenchymal stem cells in the early stage (1-4 days) of induction. Remarkably, our experiment indicated that apelin up-regulated cardiac specific genes in Wharton's jelly-derived mesenchymal stem cells via activating extracellular signal-regulated kinase (ERK) 1/2 and 5.

FW-04-806 inhibits proliferation and induces apoptosis in human breast cancer cells by binding to N-terminus of Hsp90 and disrupting Hsp90-Cdc37 complex formation.

BACKGROUND: Heat shock protein 90 (Hsp90) is a promising therapeutic target and inhibition of Hsp90 will presumably result in suppression of multiple signaling pathways. FW-04-806, a bis-oxazolyl macrolide compound extracted from China-native Streptomyces FIM-04-806, was reported to be identical in structure to the polyketide Conglobatin. METHODS: We adopted the methods of chemproteomics, computational docking, immunoprecipitation, siRNA gene knock down, Quantitative Real-time PCR and xenograft models on the research of FW-04-806 antitumor mechanism, through the HER2-overexpressing breast cancer SKBR3 and HER2-underexpressing breast cancer MCF-7 cell line. RESULTS: We have verified the direct binding of FW-04-806 to the N-terminal domain of Hsp90 and found that FW-04-806 inhibits Hsp90/cell division cycle protein 37 (Cdc37) chaperone/co-chaperone interactions, but does not affect ATP-binding capability of Hsp90, thereby leading to the degradation of multiple Hsp90 client proteins via the proteasome pathway. In breast cancer cell lines, FW-04-806 inhibits cell proliferation, caused G2/M cell cycle arrest, induced apoptosis, and downregulated Hsp90 client proteins HER2, Akt, Raf-1 and their phosphorylated forms (p-HER2, p-Akt) in a dose and time-dependent manner. Importantly, FW-04-806 displays a better anti-tumor effect in HER2-overexpressed SKBR3 tumor xenograft model than in HER2-underexpressed MCF-7 model. The result is consistent with cell proliferation assay and in vitro apoptosis assay applied for SKBR-3 and MCF-7. Furthermore, FW-04-806 has a favorable toxicity profile. CONCLUSIONS: As a novel Hsp90 inhibitor, FW-04-806 binds to the N-terminal of Hsp90 and inhibits Hsp90/Cdc37 interaction, resulting in the disassociation of Hsp90/Cdc37/client complexes and the degradation of Hsp90 client proteins. FW-04-806 displays promising antitumor activity against breast cancer cells both in vitro and in vivo, especially for HER2-overexpressed breast cancer cells.

The orphan nuclear receptor Nur77 regulates LKB1 localization and activates AMPK.

Liver kinase B1 (LKB1) has important roles in governing energy homeostasis by regulating the activity of the energy sensor kinase AMP-activated protein kinase (AMPK). The regulation of LKB1 function, however, is still poorly understood. Here we demonstrate that the orphan nuclear receptor Nur77 binds and sequesters LKB1 in the nucleus, thereby attenuating AMPK activation. This Nur77 function is antagonized by the chemical compound ethyl 2-[2,3,4-trimethoxy-6-(1-octanoyl)phenyl]acetate (TMPA), which interacts with Nur77 with high affinity and at specific sites. TMPA binding of Nur77 results in the release and shuttling of LKB1 to the cytoplasm to phosphorylate AMPKα. Moreover, TMPA effectively reduces blood glucose and alleviates insulin resistance in type II db/db and high-fat diet- and streptozotocin-induced diabetic mice but not in diabetic littermates with the Nur77 gene knocked out. This study attains a mechanistic understanding of the regulation of LKB1-AMPK axis and implicates Nur77 as a new and amenable target for the design and development of therapeutics to treat metabolic diseases.

Automatic MDSPE Combined with DART-HRMS for the Rapid Quantitation of 21 Synthetic Cathinones in Urine.

A new, rapid, and automated method for the quantitation of 21 synthetic cathinones in urine was established using magnetic dispersive solid-phase extraction (MDSPE) in combination with direct analysis in real time-high-resolution mass spectrometry (DART-HRMS). Sample preparation and quantitation were verified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Methcathinone-D3, α-PVP-D8, and proadifen (SKF525A) were used as internal standards. Magnetic HLB extractant and NaH2PO4/NaOH buffer (0.2 M, pH 7) were used in automatic MDSPE. All 21 synthetic cathinones could be detected and analyzed by DART-HRMS in under 1 min. It was proven that the linearities of 21 synthetic cathinones were suitable (R2 > 0.99) in the concentration ranges of 0.5-100 ng/mL or 1-100 ng/mL. The precision and accuracy values were all within ±15%, and the samples were stable under various conditions. The average time of each sample from preprocessing to completion of detection was approximately 2 min, allowing for rapid sample analysis. The relative error (RE) of the concentrations obtained by DART-HRMS and LC-MS/MS were within ±13.61%, and the linear coefficient (R) was 0.9964. The results of DART-HRMS and LC-MS/MS provided equivalent values at the 95% confidence level. In summary, a simple, fast, and convenient quantitation method via DART-HRMS was established. This application can be utilized to reduce backlogs and promote rapid case processing.

Rapid quantification of phenobarbital and barbital in human whole blood by liquid-liquid extraction combined with DART-orbitrap-HRMS.

PURPOSE: This study aims to develop and validate a rapid, simple, and efficient bioanalytical method for the simultaneous quantification of phenobarbital and barbital in human whole blood using liquid-liquid extraction combined with direct analysis in real time (DART) and high-resolution mass spectrometry (HRMS). METHOD: Phenobarbital-d5 and aprobarbital were selected as internal standards (ISs) of phenobarbital and barbital, respectively. A mixed solvent of o-xylene and ethyl acetate at a ratio of 1:6 was used to extract analytes of interest and ISs from 100 µL of human whole blood samples. Phenobarbital and barbital were detected by DART-HRMS. The proposed method has been validated in accordance with United States Food and Drug Administration Guidelines for Bioanalytical Method Validation in terms of selectivity, linearity, accuracy, precision, matrix effect, recovery, stability, and dilution integrity. RESULTS: The lower limits of quantification (LLOQs) of phenobarbital and barbital were both 10 ng/mL. The linearities were in the range of 10-1000 ng/mL (R2 ≥ 0.99). The mean recovery values of phenobarbital and barbital were 99.7% and 88.1%, respectively. The interday and intraday precision values were less than 10.4%, and the interday and intraday accuracy values ranged from 87.6 to 106.7%. Furthermore, the validated method was applied to four cases of phenobarbital poisoning at the Shanghai Institute of Forensic Science. CONCLUSION: The developed and fully validated method enabled the simultaneous quantification of phenobarbital and barbital in human whole blood and was successfully applied to authentic cases.

Afatinib triggers a Ni2+ -resistant Ca2+ influx pathway in A549 non-small cell lung cancer cells.

Afatinib is used to treat non-small cell lung cancer cells (NSCLC), and its mechanism involves irreversible inhibition of epidermal growth factor receptor (EGFR) tyrosine kinase. In this study, we examined if afatinib had cytotoxic action against NSCLC other than inhibition of tyrosine kinase. Afatinib (1-30 µM) caused apoptotic death in A549 NSCLC in a concentration-dependent manner. Afatinib triggered Ca2+ influx without causing Ca2+ release, and the Ca2+ influx was unaffected by sodium orthovanadate (SOV, an inhibitor of tyrosine phosphatase), suggesting that afatinib-triggered Ca2+ response was unrelated to its inhibition of tyrosine kinase. Addition of afatinib also promoted Mn2+ influx. Ca2+ influx triggered by afatinib was resistant to SKF96365 and ruthenium red (two general blockers of TRP channels) and, unexpectedly, Ni2+ (a non-specific Ca2+ channel blocker). Afatinib caused an increase in mitochondrial Ca2+ level, an initial mitochondrial hyperpolarization (4 h) and followed by mitochondrial potential collapse (24-48 h). Afatinib-induced cell death was slightly but significantly alleviated in low extracellular Ca2+ condition or under pharmacological block of mitochondrial permeability transition pore (MPTP) opening by cyclosporin A. Therefore, in addition to tyrosine kinase inhibition as a major anti-cancer mechanism of afatinib, stimulation of an atypical Ca2+ influx pathway, mitochondrial Ca2+ overload, and potential collapse in part contribute to afatinib-induced cell death.

CDN1163, a SERCA activator, causes intracellular Ca2+ leak, mitochondrial hyperpolarization and cell cycle arrest in mouse neuronal N2A cells.

OBJECTIVE: Activity or expression of sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) is diminished in some disease states such as cardiac failure and diabetes mellitus. A newly developed activator of SERCA, CDN1163, reportedly rescued or alleviated pathological conditions attributed to dysfunctional SERCA. We examined whether CDN1163 could relieve mouse neuronal N2A cell growth inhibition caused by cyclopiazonic acid (CPA, SERCA inhibitor). We also examined how CDN1163 affected cytosolic Ca2+, mitochondrial Ca2+ and mitochondrial membrane potential. METHODS: Cell viability was measured by MTT assay and trypan blue exclusion test. Cytosolic Ca2+, mitochondrial Ca2+ and mitochondrial membrane potential were measured using fura 2, Rhod-2 and JC-1, respectively, as fluorescent probes. RESULTS: CDN1163 (10 µM) itself suppressed cell proliferation, and did not alleviate CPA's inhibitory effect (and vice versa). Cell cycle was arrested at the G1 phase after CDN1163 treatment. CDN1163 treatment caused a slow yet persistent cytosolic [Ca2+] elevation partly due to Ca2+ release from an internal store other than the CPA-sensitive endoplasmic reticulum (ER). Treatment with CDN1163 for 3 h raised mitochondrial Ca2+ level and such increase was suppressed by MCU-i4 (an inhibitor of mitochondria Ca2+ uniporter, MCU), suggesting Ca2+ entered the mitochondrial matrix through MCU. Treatment of cells with CDN1163 up to 2 days resulted in mitochondrial hyperpolarization. CONCLUSION: CDN1163 caused internal Ca2+ leak, cytosolic Ca2+ overload, mitochondrial Ca2+ elevation and hyperpolarization, cell cycle arrest and cell growth inhibition.

[Impact analysis of atmospheric state for target detection in hyperspectral radiance image].

Target detection based on hyperspectral radiance images can improve data processing efficiency to meet the requirements of real-time processing. However, the spectral radiance acquired by the remote sensor will be affected by the atmosphere. In the present paper, hyperspectral imaging process is simulated to analyze the effects of the changes in atmospheric state on target detection in hyperspectral radiance image. The results show that hyperspectral radiance image can be directly used for target detection, different atmospheric states have little impacts on the RXD detection, whereas the MF detection is dependent on the accuracy of the input spectrum, and good results can only be obtained by the MF detector when the atmospheric states are similar between the radiance spectrum of the target to be detected and the simulated hyperspectral image.

Phonon and Exciton Properties between WS2 and MoS2 Layers via Inversion Heterostructure Engineering.

Recently, two-dimensional (2D) van der Waals heterostructures (vdWHs) have exhibited emergent electronic and optical properties due to their peculiar phonons and excitons, which lay the foundation for the development of photoelectronic devices. The dielectric environment plays an important role in the interlayer coupling of vdWHs. Here, we studied the interlayer and extra-layer dielectric effects on phonon and exciton properties in WS2/MoS2 and MoS2/WS2 vdWHs by Raman and photoluminescence (PL) spectroscopy. The ultralow frequency (ULF) Raman modes are insensitive to atomic arrangement at the interface between 1LW and 1LM and dielectric environments of neighboring materials, and the layer breathing mode (LBM) frequency follows that of WS2. The shift of high-frequency (HF) Raman modes is attributable to interlayer dielectric screening and charge transfer effects. Furthermore, the energy of interlayer coupling exciton peak I is insensitive to atomic arrangement at the interface between 1LW and 1LM and its energy follows that of MoS2, but the slight intensity difference in inversion vdWHs means that the substrate's dielectric properties may induce doping on the bottom layer. This paper provides fundamental understanding of phonon and exciton properties of such artificially formed vdWHs structures, which is important for new insights into manipulating the performances of potential devices.

Suppression of Ca2+ oscillations by SERCA inhibition in human alveolar type 2 A549 cells: rescue by ochratoxin A but not CDN1163.

AIMS: Lung type 2 alveolar cells, by secreting surfactant to lower surface tension, contribute to enhance lung compliance. Stretching, as a result of lung expansion, triggers type 1 alveolar cell to release ATP, which in turn stimulates Ca2+-dependent surfactant secretion by neighboring type 2 cells. In this report, we studied ATP-triggered Ca2+ signaling in human alveolar type 2 A549 cells. MAIN METHODS: Ca2+ signaling was examined using microfluorimetric measurement with fura-2 as fluorescent dye. KEY FINDINGS: Ca2+ oscillations triggered by ATP relied on inositol 1,4,5-trisphosphate-induced Ca2+ release and store-operated Ca2+ entry. Pathological conditions such as influenza virus infection and diabetes reportedly inhibit sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA). We found that a very mild inhibition of SERCA by cyclopiazonic acid (CPA) sufficed to decrease Ca2+ oscillation frequency and the percentage of cells exhibiting Ca2+ oscillations. Ochratoxin A (OTA), an activator of SERCA, could prevent the suppressive effects by CPA. Inhibition of SERCA by hydrogen peroxide also suppressed Ca2+ oscillations. Interestingly, hydrogen peroxide-induced inhibition was prevented by OTA but aggravated by CDN1163, an allosteric activator of SERCA. CDN1163 also had an untoward effect of releasing intracellular Ca2+. SIGNIFICANCE: Different modes of activation of SERCA may determine the outcome of rescue of Ca2+ oscillations in case of SERCA inhibition in alveolar type 2 cells.