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- ArticleTrauma Mon. 2014 Nov;19(4):e22699.[This corrects the article DOI: 10.5812/traumamon.10946.].
- ArticleUshio-Fukai M, Alexander RW, Akers M, Yin Q, Fujio Y, Walsh K, Griendling KK.J Biol Chem. 1999 Aug 06;274(32):22699-704.Angiotensin II, a hypertrophic/anti-apoptotic hormone, utilizes reactive oxygen species (ROS) as growth-related signaling molecules in vascular smooth muscle cells (VSMCs). Recently, the cell survival protein kinase Akt/protein kinase B (PKB) was proposed to be involved in protein synthesis. Here we show that angiotensin II causes rapid phosphorylation of Akt/PKB (6- +/- 0.4-fold increase). Exogenous H(2)O(2) (50-200 microM) also stimulates Akt/PKB phosphorylation (maximal 8- +/- 0.2-fold increase), suggesting that Akt/PKB activation is redox-sensitive. Both angiotensin II and H(2)O(2) stimulation of Akt/PKB are abrogated by the phosphatidylinositol 3-kinase (PI3-K) inhibitors wortmannin and LY294002 (2(4-morpholinyl)-8-phenyl-4H-1-benzopyran-4-one), suggesting that PI3-K is an upstream mediator of Akt/PKB activation in VSMCs. Furthermore, diphenylene iodonium, an inhibitor of flavin-containing oxidases, or overexpression of catalase to block angiotensin II-induced intracellular H(2)O(2) production significantly inhibits angiotensin II-induced Akt/PKB phosphorylation, indicating a role for ROS in agonist-induced Akt/PKB activation. In VSMCs infected with dominant-negative Akt/PKB, angiotensin II-stimulated [(3)H]leucine incorporation is attenuated. Thus, our studies indicate that Akt/PKB is part of the remarkable spectrum of angiotensin II signaling pathways and provide insight into the highly organized signaling mechanisms coordinated by ROS, which mediate the hypertrophic response to angiotensin II in VSMCs.
- ArticleCao X, Wang R, Wang K, Gu Z, Wang F.ACS Omega. 2021 Sep 07;6(35):22688-22699.The catalytic performance of the selective isomerization of o-ethyltoluene (O-ET) is crucial to increasing the m-ethyltoluene (M-ET) and p-ethyltoluene (P-ET) yields. During the isomerization of O-ET, traditional (commercial) mordenites (HM) are generally limited by a high reaction temperature (235 °C), as well as a low yield of the isomerization product (49.0%). In this study, micro-mesoporous mordenites were obtained by treating commercial mordenites with NaOH, NaOH-HNO3, and NaOH-mixed acid (HNO3-oxalic). Thereafter, their structure, porosity, and acidity were investigated via X-ray diffraction, transmission electron microscopy, inductively coupled plasma, N2 sorption, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy of pyridine, temperature-programmed desorption of ammonia, and nuclear magnetic resonance. Among the various treated samples, the accessibility of the acidic sites and the B/L value of the alkali-mixed HNO3-oxalic one were enhanced, achieving the highest yield (53.6%) and lowest reaction temperature (165 °C), thus significantly reducing the energy consumption of the reaction process. Furthermore, Ni and Ce were successfully loaded via the incipient wetness impregnation of the micro-mesoporous mordenite to significantly prolong the catalytic life. This study affords a new strategy for obtaining high M-ET and P-ET yields from the isomerization of O-ET in mixed C9 aromatics on an industrial scale.
- ArticleWei G, Xue L, Zhu Y, Qian X, Zou L, Jin Q, Wang D, Ge G.J Biochem Mol Toxicol. 2021 Apr;35(4):e22699.Statins are a group of hydroxymethylglutaryl coenzyme A reductase inhibitors that are used in the treatment of cardiovascular diseases. However, statins have been found to be cytotoxic, and many unexpected side effects have been reported in clinical applications. The susceptibilities of different cell lines toward statins are diverse, and the mechanisms of cytotoxicity remain unknown. Therefore, the present study aimed to investigate differences in the susceptibility to and mechanisms of statin-induced cytotoxicity in two cell lines, HT-29 and A549, using a high content screening-based multiparametric toxicity assay panel. We found that the two cell types exhibited differing susceptibilities to the cytotoxic effects of the different statins. Additionally, the cytotoxicity was inconsistent between different statins in the two cell lines. Four statins with strong cytotoxicity decreased the viability of HT-29 cells via the mitochondrial pathway, as evidenced by decreased mitochondrial membrane potential, and elevated mitochondrial mass, calcium release and cell apoptosis, and reactive oxygen species. In contrast, these four statins only induced a decrease in the mitochondrial membrane potential in A549 cells. The above results provide an objective reason for future evaluations of cytotoxic differences in cell types and the underlying mechanisms of cytotoxicity in different statins, and provide a good scientific basis for further research on countermeasures against statin-induced cell injuries.
- ArticleDubiel W, Ferrell K, Pratt G, Rechsteiner M.J Biol Chem. 1992 Nov 15;267(32):22699-702.Ubiquitinated proteins are degraded by a 26 S ATP-dependent protease. SDS-polyacrylamide gel electrophoresis analysis of the purified 26 S enzyme reveals more than 20 polypeptides ranging in apparent molecular masses from 20 to 110 kDa. Although many of the subunits smaller than 30 kDa are members of the multicatalytic protease family, the identity and function of the larger polypeptides have remained unknown. We report here the cDNA sequence for subunit 4, a 51-kDa chain of the 26 S protease. Subunit 4 belongs to a recently identified eukaryotic ATPase family, which includes proteins involved in peroxisome formation, secretion, and human immunodeficiency virus gene expression. Subunit 4 also shows weak similarity to ClpA, the ATP-binding subunit of the Escherichia coli protease, Clp.
- ArticleVerma P, Tasior M, Roy P, Meech SR, Gryko DT, Vauthey E.Phys Chem Chem Phys. 2023 Aug 30;25(34):22689-22699.A significant number of quadrupolar dyes behave as their dipolar analogues when photoexcited in polar environments. This is due to the occurrence of excited-state symmetry breaking (ES-SB), upon which the electronic excitation, initially distributed over the whole molecule, localises preferentially on one side. Here, we investigate the ES-SB properties of two A-D-A dyes, consisting of a pyrrolo-pyrrole donor (D) and either cyanophenyl or dicyanovinyl acceptors (A). For this, we use time-resolved vibrational spectroscopy, comparing IR absorption and femtosecond stimulated Raman spectroscopies. Although dicyanovinyl is a stronger electron-withdrawing group, ES-SB is not observed with the dicyanovinyl-based dye even in highly polar media, whereas it already takes place in weakly polar solvents with dyes containing cyanophenyl accepting groups. This difference is attributed to the large electronic coupling between the D-A branches in the former dye, whose loss upon symmetry breaking cannot be counterbalanced by a gain in solvation energy. Comparison with analogues of the cyanophenyl-based dye containing different spacers reveals that interbranch coupling does not so much depend on the distance between the D-A subunits than on the nature of the spacer. We show that transient Raman spectra probe different modes of these centrosymmetric molecules but are consistent with the transient IR data. However, lifetime broadening of the Raman bands, probably due to the resonance enhancement, may limit the application of this technique for monitoring ES-SB.
- ArticleMcManus JW, Walmsley T, Nagaya K, Harries JR, Kumagai Y, Iwayama H, Ashfold MNR, Britton M, ... Show More Bucksbaum PH, Downes-Ward B, Driver T, Heathcote D, Hockett P, Howard AJ, Kukk E, Lee JWL, Liu Y, Milesevic D, Minns RS, Niozu A, Niskanen J, Orr-Ewing AJ, Owada S, Rolles D, Robertson PA, Rudenko A, Ueda K, Unwin J, Vallance C, Burt M, Brouard M, Forbes R, Allum F.Phys Chem Chem Phys. 2022 Sep 28;24(37):22699-22709.We present results from an experimental ion imaging study into the fragmentation dynamics of 1-iodopropane and 2-iodopropane following interaction with extreme ultraviolet intense femtosecond laser pulses with a photon energy of 95 eV. Using covariance imaging analysis, a range of observed fragmentation pathways of the resulting polycations can be isolated and interrogated in detail at relatively high ion count rates (∼12 ions shot-1). By incorporating the recently developed native frames analysis approach into the three-dimensional covariance imaging procedure, contributions from three-body concerted and sequential fragmentation mechanisms can be isolated. The angular distribution of the fragment ions is much more complex than in previously reported studies for triatomic polycations, and differs substantially between the two isomeric species. With support of simple simulations of the dissociation channels of interest, detailed physical insights into the fragmentation dynamics are obtained, including how the initial dissociation step in a sequential mechanism influences rovibrational dynamics in the metastable intermediate ion and how signatures of this nuclear motion manifest in the measured signals.
- ArticleBurrill DJ, Lambrecht DS.Phys Chem Chem Phys. 2020 Oct 15;22(39):22699-22710.The adsorption of nitric oxide and nitrogen dioxide (NOx) to the Buckybowls sumanene and corannulene was investigated. Binding energies were up to 1.8× larger than for coronene as the planar analogue, demonstrating the advantages of Buckybowls for gas adsorption. In agreement with previous reports on carbon dioxide and methane adsorption, the favorable binding energies for NOx were shown to be associated with the curvature of the Buckybowls. It is shown that applying an electric field along the bowl symmetry axis modifies the bowl curvatures and impacts adsorbate binding energies, including the potential to desorb adsorbates. As a proof of concept, it is shown that applying electric fields of different strengths and orientations selectively controls sumanene's preference to bind nitric oxide, nitrogen dioxide, and carbon dioxide, suggesting potential applications for dynamically tunable gas adsorption. Moreover, it is demonstrated that adsorbates can be desorbed by applying suitable electric field strengths, allowing cleaning of the Buckybowls for renewed usage.
- ArticleChen WK, Fang WH, Cui G.Phys Chem Chem Phys. 2019 Oct 24;21(41):22695-22699.We developed a multi-layer energy-based fragment (MLEBF) method within the many-body energy expansion framework. It supplies accurate energies and gradients, and accurately reproduces excited-state topological structures. Moreover, MLEBF-based nonadiabatic dynamics simulations give nearly the same results compared with full ab initio ones. The present work could stimulate developing energy-based fragment methods for photochemistry of large systems.
- DatabaseSummary: This FAIRsharing record describes: Vivli is a non-profit organization working to advance human health through the insights and discoveries gained by sharing and analyzing data. It is home to an independent global data-sharing and analytics platform which serves all elements of the international research community. The platform includes a data repository, in-depth search engine and cloud-based analytics, and harmonizes governance, policy and processes to make sharing data easier. Vivli acts as a neutral broker between data contributor and data user and the wider data sharing community. The source of this description is the metadata record on FAIRsharing.org, an educational and informative resource that describes and links databases, standards, and data policies. FAIRsharing also creates collections of these resources and recommendations of databases and standards based on 3rd party data policies.Users must sign up using their Stanford email address
- ArticleLiu X, Zhao C, Yang L, Zhang J, Sun R.Phys Chem Chem Phys. 2017 Aug 30;19(34):22691-22699.Central atoms have a significant influence on the reaction kinetics and dynamics of nucleophilic substitution (SN2). Herein, atomistic dynamics of a prototype SN2@N reaction F- + NH2Cl is uncovered employing direct dynamics simulations that show strikingly distinct features from those determined for a SN2@C congener F- + CH3Cl. Indirect scattering is found to prevail, which proceeds predominantly through a hydrogen-bonded F--HNHCl complex in the reactant entrance channel. This unexpected finding of a pronounced contribution of indirect reaction dynamics, even at a high collision energy, is in strong contrast to a general evolution from indirect to direct dynamics with enhanced energy that characterizes SN2@C. This result suggests that the relative importance of different atomic-level mechanisms may depend essentially on the interaction potential of reactive encounters and the coupling between inter- and intramolecular modes of the pre-reaction complex. For F- + NH2Cl the proton transfer pathway is less competitive than SN2. A remarkable finding is that the more favorable energetics for NH2Cl proton transfer, as compared to that for CH3Cl, does not manifest itself in the reaction dynamics. The present work sheds light on the underlying reaction dynamics of SN2@N, which remain largely unclear compared to well-studied SN2@C.
- ArticleTang C, Hou YX, Shi PX, Zhu CH, Lu X, Wang XL, Que LL, Zhu GQ, Liu L, Chen Q, Li CF, Xu Y, Li JT, Li YH.FASEB J. 2023 01;37(1):e22699.Cardiac fibrosis is an essential pathological process in pressure overload (PO)-induced heart failure. Recently, myocyte-fibroblast communication is proven to be critical in heart failure, in which, pathological growth of cardiomyocytes (CMs) may promote fibrosis via miRNAs-containing exosomes (Exos). Peli1 regulates the activation of NF-κB and AP-1, which has been demonstrated to engage in miRNA transcription in cardiomyocytes. Therefore, we hypothesized that Peli1 in CMs regulates the activation of cardiac fibroblasts (CFs) through an exosomal miRNA-mediated paracrine mechanism, thereby promoting cardiac fibrosis. We found that CM-conditional deletion of Peli1 improved PO-induced cardiac fibrosis. Moreover, Exos from mechanical stretch (MS)-induced WT CMs (WT MS-Exos) promote activation of CFs, Peli1-/- MS-Exos reversed it. Furthermore, miRNA microarray and qPCR analysis showed that miR-494-3p was increased in WT MS-Exos while being down regulated in Peli1-/- MS-Exos. Mechanistically, Peli1 promoted miR-494-3p expression via NF-κB/AP-1 in CMs, and then miR-494-3p induced CFs activation by inhibiting PTEN and amplifying the phosphorylation of AKT, SMAD2/3, and ERK. Collectively, our study suggests that CMs Peli1 contributes to myocardial fibrosis via CMs-derived miR-494-3p-enriched exosomes under PO, and provides a potential exosomal miRNA-based therapy for cardiac fibrosis.
- ArticleYang Y, Ding M, Di N, Azziz R, Yang D, Zhao X.J Clin Lab Anal. 2019 Mar;33(3):e22699.BACKGROUND: To investigate the correlation between hyperandrogenism (HA) and insulin resistance (IR) in women with polycystic ovary syndrome (PCOS) by measuring serum total testosterone (TT) using a liquid chromatography and tandem mass spectrometry assay (LC-MS/MS).
METHODS: This cohort study included 332 patients with PCOS, 63 patients with IR and 276 with controls. TT levels were measured by LC-MS/MS and chemiluminescent immunoassay (CLIA); glucose and insulin levels were determined by an oral glucose tolerance test (OGTT).
RESULTS: Compared with CLIA, LC-MS/MS differentiated more cases with high TT levels among the non-PCOS subjects with IR In patients with PCOS, LC-MS/MS-based TT levels or a combination with the mFG score detected a significantly higher incidence of HA in subjects with IR identified by hyperinsulinemia (HIN), HOMA-IR or impaired fasting glucose (IFG) than in those without IR Conversely, the IR rates demonstrated by HIN, HOMA-IR, or IFG were remarkably higher in the LC-MS/MS-defined high TT subgroup than in the normal TT subgroup. However, the CLIA platform could not discern a difference in HA incidence between IR and non-IR subgroups or in IR rate between high and normal TT populations. ROC curves also proved that HIN, HOMA-IR, and IFG were positive contributors to HA as measured by LC-MS/MS CONCLUSIONS: The correlation between HA and IR has always been underestimated, partly owing to the less accurate methods previously used to measure TT. HIN, HOMA-IR, and IFG are likely to contribute to the development of HA from a clinical perspective. - ArticleVezzani A, Lang B, Aronica E.Cold Spring Harb Perspect Med. 2015 Dec 18;6(2):a022699.This review reports the available evidence on the activation of the innate and adaptive branches of the immune system and the related inflammatory processes in epileptic disorders and the putative pathogenic role of inflammatory processes developing in the brain, as indicated by evidence from experimental and clinical research. Indeed, there is increasing knowledge supporting a role of specific inflammatory mediators and immune cells in the generation and recurrence of epileptic seizures, as well as in the associated neuropathology and comorbidities. Major challenges in this field remain: a better understanding of the key inflammatory pathogenic pathways activated in chronic epilepsy and during epileptogenesis, and how to counteract them efficiently without altering the homeostatic tissue repair function of inflammation. The relevance of this information for developing novel therapies will be highlighted.
- ArticleYin H, Chen J, Guan P, Zheng D, Kong Q, Yang S, Zhou P, Yang B, Pullerits T, Han K.Angew Chem Int Ed Engl. 2021 Oct 11;60(42):22693-22699.Lead-free halide perovskites have triggered interest in the field of optoelectronics and photocatalysis because of their low toxicity, and tunable optical and charge-carrier properties. From an application point of view, it is desirable to develop stable multifunctional lead-free halide perovskites. We have developed a series of Cs2 Ptx Sn1-x Cl6 perovskites (0≤x≤1) with high stability, which show switchable photoluminescence and photocatalytic functions by varying the amount of Pt4+ substitution. A Cs2 Ptx Sn1-x Cl6 solid solution with a dominant proportion of Pt4+ shows broadband photoluminescence with a lifetime on the microsecond timescale. A Cs2 Ptx Sn1-x Cl6 solid solution with a small amount of Pt4+ substitution exhibits photocatalytic hydrogen evolution activity. An optical spectroscopy study reveals that the switch between photoluminescence and photocatalysis functions is controlled by sub-band gap states. Our finding provides a new way to develop lead-free multifunctional halide perovskites with high stability.
- ArticleWu DW, Lin PL, Cheng YW, Huang CC, Wang L, Lee H.Oncotarget. 2016 Apr 19;7(16):22687-99.DDX3 plays a dual role in colorectal cancer; however, the role and underlying mechanism of DDX3 in colorectal tumorigenesis remains unclear. Here, we provide evidence that DDX3 enhances oncogenic KRAS transcription via an increase in SP1 binding to its promoter. Accelerating oncogenic KRAS expression by DDX3 promotes the invasion capability via the ERK/PTEN/AKT/β-catenin cascade. Moreover, the β-catenin/ZEB1 axis is responsible for DDX3-induced cell invasiveness and xenograft lung tumor nodule formation. The xenograft lung tumor nodules induced by DDX3-overexpressing T84 stable clone were nearly suppressed by the inhibitor of AKT (perifosine) or β-catenin (XAV939). Among patients, high KRAS, positive nuclear β-catenin expression and high ZEB1 were more commonly occurred in high-DDX3 tumors than in low-DDX3 tumors. High-DDX3, high-KRAS, positive nuclear β-catenin tumors, and high-ZEB1 exhibited worse overall survival (OS) and relapse free survival (RFS) than their counterparts. In conclusion, DDX3 may play an oncogenic role to promote tumor growth and invasion in colon cancer cells via the β-catenin/ZEB1 axis due to increasing KRAS transcription. We therefore suggest that AKT or β-catenin may potentially act as a therapeutic target to improve tumor regression and outcomes in colorectal cancer patients who harbored high-DDX3 tumors.
- ArticleFu Y, Huang ZJ.Proc Natl Acad Sci U S A. 2010 Dec 28;107(52):22699-704.Neurexins (NRXs) and neuroligins are key synaptic adhesion molecules that also recruit synaptic signaling machineries. Neurexins consist of α- and β-isoforms, but how they couple synaptic transmission and adhesion to regulate activity-dependent synapse development remains unclear, in part because of poor understanding of their cell biology and regulation in the relevant neurons. Here, we examined the subaxonal localization, dynamics, and regulation of NRX1α and NRX1β in cortical perisomatic inhibitory synapses. Both isoforms are delivered to presynaptic terminals but show significant and different turnover rate at the membrane. Although NRX1α is highly diffuse along developing axons and filopodia, NRX1β is strictly anchored at terminals through binding to postsynaptic ligands. The turnover rate of NRX1β is attenuated by neural activity and presynaptic GABA(B) receptors. NRXs, thus, are intrinsically dynamic but are stabilized by local transmitter release. Such an activity-adjusted adhesion system seems ideally suited to rapidly explore and validate synaptic partners guided by synaptic transmission.
- ArticlePerrone S, Vilaseca R, Masoller C.Opt Express. 2012 Sep 24;20(20):22692-9.We study numerically the dynamics of a vertical-cavity surface-emitting laser (VCSEL) with optical injection and show that the interplay of polarization bistability and noise yields a reliable logic output to two logic inputs. Specifically, by encoding the logic inputs in the strength of the light injected into the suppressed polarization mode of the VCSEL (the so-called 'orthogonal' injection), and by decoding the output logic response from the polarization state of the emitted light, we demonstrate an all-optical stochastic logic gate that exploits the ubiquitous presence of noise. It gives the correct logic output response for as short as 5 ns bit times when the dimensionless spontaneous emission coefficient, β(sp), is within the range 10(-4)-10(-1). Considering that typical values of β(sp) in semiconductor lasers are in the range 10(-5)-10(-4), the VCSEL-based logic gate can be implemented with nowadays commercially available VCSELs, exploiting either their intrinsic noise, or external and background noise sources.
- ArticleWang T, Wang J.J Phys Chem B. 2005 Dec 01;109(47):22699; author reply 22700.
- ArticleSmerdel-Ramoya A, Zanotti S, Deregowski V, Canalis E.J Biol Chem. 2008 Aug 15;283(33):22690-9.Connective tissue growth factor (CTGF), a member of the CCN family of proteins, is expressed by osteoblasts, but its function in cells of the osteoblastic lineage has not been established. We investigated the effects of CTGF overexpression by transducing murine ST-2 stromal cells with a retroviral vector, where CTGF is under the control of the cytomegalovirus promoter. Overexpression of CTGF in ST-2 cells increased alkaline phosphatase activity, osteocalcin and alkaline phosphatase mRNA levels, and mineralized nodule formation. CTGF overexpression decreased the effect of bone morphogenetic protein-2 on Smad 1/5/8 phosphorylation and of Wnt 3 on cytosolic beta-catenin, indicating that the stimulatory effect on osteoblastogenesis was unrelated to BMP and Wnt signaling. CTGF overexpression suppressed Notch signaling and induced the transcription of hairy and E (spl)-1 (HES)-1, by Notch-independent mechanisms. CTGF induced nuclear factor of activated T cells (NFAT) transactivation by a calcineurin-dependent mechanism. Down-regulation of CTGF enhanced Notch signaling and decreased HES-1 transcription and NFAT transactivation. Similar effects were observed following forced CTGF overexpression, the addition of CTGF protein, or the transduction of ST-2 cells with a retroviral vector expressing HES-1. In conclusion, CTGF enhances osteoblastogenesis, possibly by inhibiting Notch signaling and inducing HES-1 transcription and NFAT transactivation.