Aldehyde dehydrogenase 1 (ALDH1) is a cancer stem-like cell (CSC) marker in human cancers; however, the specific ALDH1-regulated function and its underlying signalling pathways have not been fully demonstrated. Here, we investigated the ALDH1-regulated function and its underlying signalling and tested whether all-trans retinoic acid (ATRA) can suppress ALDH1-regulated tumour behaviour in ovarian cancer cells. By modulating ALDH1 expression using flow cytometry enrichment and exogenous overexpression or knockdown, we showed that the ALDH1 activity is positively correlated with stemness in ovarian cancer cells according to measures such as sphere formation and CSC marker expression as well as tumourigenesis in a mouse xenograft model.
View Article and Find Full Text PDFDiverse transition metal hydroxide nanostructures were synthesized by laser-induced hydrolysis in a liquid precursor solution for alkaline oxygen evolution reaction (OER). Several active OER catalysts with fine control of composition, structure, and valence state were obtained including (Lix)[Ni0.66Mn0.
View Article and Find Full Text PDFApert syndrome (AS) is a type of autosomal dominant disease characterized by premature fusion of the cranial sutures, severe syndactyly, and other abnormalities in internal organs. Approximately 70% of AS cases are caused by a single mutation, S252W, in fibroblast growth factor receptor 2 (FGFR2). Two groups have generated FGFR2 knock-in mice Fgfr2S252W/+ that exhibit features of AS.
View Article and Find Full Text PDFWe elucidate the role of room-temperature-induced instantaneous structural distortions in the Li K-edge X-ray absorption spectra (XAS) of crystalline LiF, Li2SO4, Li2O, Li3N, and Li2CO3 using high resolution X-ray Raman spectroscopy (XRS) measurements and first-principles density functional theory calculations within the eXcited electron and Core Hole approach. Based on thermodynamic sampling via ab initio molecular dynamics simulations, we find calculated XAS in much better agreement with experiment than those computed using the rigid crystal structure alone. We show that local instantaneous distortion of the atomic lattice perturbs the symmetry of the Li 1s core-excited-state electronic structure, broadening spectral line-shapes and, in some cases, producing additional spectral features.
View Article and Find Full Text PDFNanoparticle electrodes in lithium-ion batteries have both near-surface and interior contributions to their redox capacity, each with distinct rate capabilities. Using combined electron microscopy, synchrotron X-ray methods and ab initio calculations, we have investigated the lithiation pathways that occur in NiO electrodes. We find that the near-surface electroactive (Ni(2+) → Ni(0)) sites saturated very quickly, and then encounter unexpected difficulty in propagating the phase transition into the electrode (referred to as a "shrinking-core" mode).
View Article and Find Full Text PDFHighly active catalysts for the oxygen evolution reaction (OER) are required for the development of photoelectrochemical devices that generate hydrogen efficiently from water using solar energy. Here, we identify the origin of a 500-fold OER activity enhancement that can be achieved with mixed (Ni,Fe)oxyhydroxides (Ni(1-x)Fe(x)OOH) over their pure Ni and Fe parent compounds, resulting in one of the most active currently known OER catalysts in alkaline electrolyte. Operando X-ray absorption spectroscopy (XAS) using high energy resolution fluorescence detection (HERFD) reveals that Fe(3+) in Ni(1-x)Fe(x)OOH occupies octahedral sites with unusually short Fe-O bond distances, induced by edge-sharing with surrounding [NiO6] octahedra.
View Article and Find Full Text PDFAxial Cu-S(Met) bonds in electron transfer (ET) active sites are generally found to lower their reduction potentials. An axial S(Met) bond is also present in cytochrome c (cyt c) and is generally thought to increase the reduction potential. The highly covalent nature of the porphyrin environment in heme proteins precludes using many spectroscopic approaches to directly study the Fe site to experimentally quantify this bond.
View Article and Find Full Text PDFA variety of nanoscale delivery systems have been shown to enhance the oral absorption of poorly water-soluble and poorly permeable drugs. However, the performance of these systems has seldom been evaluated simultaneously. The aim of this study was to compare the bioavailability enhancement effect of lipid-based nanocarriers with poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) to highlight the importance of the lipid composition, with cyclosporine A (CyA) as a model drug.
View Article and Find Full Text PDFLeflunomide, an immunosuppressant with antiviral activity, was used to treat 5 children with severe BK virus-associated hemorrhagic cystitis after hematopoietic stem cell transplantation. Without severe side effects, BK viral loads in blood and urine decreased significantly after leflunomide treatment. Compared with 7 historical controls, duration of BK virus-associated hemorrhagic cystitis was significantly shorter in patients receiving leflunomide therapy (P < 0.
View Article and Find Full Text PDFRationale: Idiopathic pulmonary fibrosis (IPF) is a deadly lung disease with few therapeutic options. Apoptosis of alveolar epithelial cells, followed by abnormal tissue repair characterized by hyperplastic epithelial cell formation, is a pathogenic process that contributes to the progression of pulmonary fibrosis. However, the signaling pathways responsible for increased proliferation of epithelial cells remain poorly understood.
View Article and Find Full Text PDFMucin 2 (MUC2) is the major secreted mucin of the large intestine and is expressed by adenomas and mucinous carcinomas. Since colon cancer is associated with a proinflammatory microenvironment and dysregulated MUC2 expression, the aim of this study was to characterize the effects of MUC2 gene expression in colon tumor progression using colonic cancer cells. CT26 colon cancer cells were stably transfected with MUC2 siRNA (MUC2 RNAi) or a control construct containing a nonspecific sequence (scrambled RNAi).
View Article and Find Full Text PDFIdiopathic pulmonary fibrosis (IPF) is a lethal, fibroproliferative disease. Pulmonary hypertension (PH) can develop secondary to IPF and increase mortality. Alternatively, activated macrophages (AAMs) contribute to the pathogenesis of both IPF and PH.
View Article and Find Full Text PDFPurpose: To increase understanding about the effects of moderate-intensity physical activity on cognitive function, the current study examined whether a single bout of aerobic exercise exerts differential effects on distinct aspects of executive function in healthy young adults.
Methods: A within-subjects study was designed where 26 young adult participants (mean age = 25.23 yr, 12 males) engaged in a 30-min bout of both (a) moderate-intensity aerobic cycling and (b) passive motor-driven cycling, occurring on two separate occasions and counterbalanced in their order.
Hyperoxic lung injury is characterized by cellular damage from high oxygen concentrations that lead to an inflammatory response in the lung with cellular infiltration and pulmonary edema. Adenosine is a signaling molecule that is generated extracellularly by CD73 in response to injury. Extracellular adenosine signals through cell surface receptors and has been found to be elevated and plays a protective role in acute injury situations.
View Article and Find Full Text PDFThe aim of this study was to compare various formulations solid dispersion pellets (SDP), nanostructured lipid carriers (NLCs) and a self-microemulsifying drug delivery system (SMEDDS) generally accepted to be the most efficient drug delivery systems for BCS II drugs using fenofibrate (FNB) as a model drug. The size and morphology of NLCs and SMEDDS was characterized by dynamic light scattering (DLS) and transmission electron microscopy (TEM). Their release behaviors were investigated in medium with or without pancreatic lipase.
View Article and Find Full Text PDFNanoconfined alkali metal borohydrides are promising materials for reversible hydrogen storage applications, but the characterization of hydrogen sorption in these materials is difficult. Here we show that with in situ X-ray Raman spectroscopy (XRS) we can track the relative amounts of intermediates and final products formed during de- and re-hydrogenation of nanoconfined lithium borohydride (LiBH4) and therefore we can possibly identify the de- and re-hydrogenation pathways. In the XRS of nanoconfined LiBH4 at different points in the de- and re-hydrogenation, we identified phases that lead to the conclusion that de- and re-hydrogenation pathways in nanoconfined LiBH4 are different from bulk LiBH4: intercalated lithium (LiCx), boron and lithium hydride were formed during de-hydrogenation, but as well Li2B12H12 was observed indicating that there is possibly some bulk LiBH4 present in the nanoconfined sample LiBH4-C as prepared.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
August 2014
We generate time series from scale-free networks based on a finite-memory random walk traversing the network. These time series reveal topological and functional properties of networks via their temporal correlations. Remarkably, networks with different node-degree mixing patterns exhibit distinct self-similar characteristics.
View Article and Find Full Text PDFExtensive study of the electronic structure of Fe-NO complexes using a variety of spectroscopic methods was attempted to understand how iron controls the binding and release of nitric oxide. The comparable energy levels of NO π* orbitals and Fe 3d orbitals complicate the bonding interaction within Fe-NO complexes and puzzle the quantitative assignment of NO oxidation state. Enemark-Feltham notation, {Fe(NO)x}(n), was devised to circumvent this puzzle.
View Article and Find Full Text PDFZhonghua Liu Xing Bing Xue Za Zhi
June 2014
Objective: To describe the epidemiological characteristics on the supplement of folic acid in progestation and early pregnancy, and to probe the protective effects of supplement of folic acid in early pregnancy against pregnant depression, in Ma'anshan city, Anhui province.
Methods: In this cohort study, 5 150 subjects who had their first antenatal examination at Ma'anshan Maternal and Child Care Centers were recruited under informed consent, from October 2008 to October 2010. All the information were collected through questionnaires in the first, second and third trimesters respectively.
Phys Rev E Stat Nonlin Soft Matter Phys
July 2014
We present a dynamically equivalent transformation between time series and complex networks based on coarse geometry theory. In terms of quasi-isometric maps, we characterize how the underlying geometrical characters of complex systems are preserved during transformations. Fractal dimensions are shown to be the same for time series (or complex network) and its transformed counterpart.
View Article and Find Full Text PDFHeterogeneous nuclear ribonucleoprotein K (hnRNPK) is an RNA/DNA-binding protein involved in chromatin remodeling, RNA processing and the DNA damage response. In addition, increased hnRNPK expression has been associated with tumor development and progression. A variety of post-translational modifications of hnRNPK have been identified and shown to regulate hnRNPK function, including phosphorylation, ubiquitination, sumoylation and methylation.
View Article and Find Full Text PDFMutant Kras (V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog) is observed in more than 20% of non-small-cell lung cancers; however, no effective Kras target therapy is available at present. The Kras DNA vaccine may represent as a novel immunotherapeutic agent in lung cancer. In this study, we investigated the antitumor efficacy of the Kras DNA vaccine in a genetically engineered inducible mouse lung tumor model driven by Kras(G12D).
View Article and Find Full Text PDFThe dioxygen we breathe is formed by light-induced oxidation of water in photosystem II. O2 formation takes place at a catalytic manganese cluster within milliseconds after the photosystem II reaction centre is excited by three single-turnover flashes. Here we present combined X-ray emission spectra and diffraction data of 2-flash (2F) and 3-flash (3F) photosystem II samples, and of a transient 3F' state (250 μs after the third flash), collected under functional conditions using an X-ray free electron laser.
View Article and Find Full Text PDFObjective: To investigate the role of Vhl in maintaining the integrity of articular cartilage and in the development of experimental osteoarthritis (OA).
Method: Histology of articular cartilage and subchondral bone in both Vhl cKO and WT mice were analyzed by histopathology and micro-CT. Articular cartilage destruction and proteoglycan loss were scored in aged (12-month-old) mice as well as in mice with surgically induced OA.