bluuebunny/crossref_metadata_2025 huggingface dataset:
Pentanuclear {Cr2Ln3} (Ln = Dy, Tb) Heterometallic Clusters Based on an Amino Acid Ligand: Slow Relaxation of Magnetization and Substitution Reactions
Authors: Wang Xiao‐Qun , Li Zhong‐Yi , Zhu Zhao‐Xiang , Zhu Jiang , Liu Shu‐Qin , Ni Jun , Zhang Jian‐Jun
Published: August 2013

Reactions between Ln3+ (Ln = Dy, Tb), Cr3+, and glycine (HGly) in aqueous solution led to two pentanuclear compounds, Na3[Dy3Cr2(HGly)6(μ3‐OH)6(H2O)9]·(ClO4)8·Cl4·14H2O (1) and Na3[Tb3Cr2(HGly)6(μ3‐OH)6(H2O)9]·(ClO4)6·Cl6·6H2O (2). Structural analyses showed that both 1 and 2 have a {Ln3Cr2} compressed trigonal‐bipyramidal skeleton in which an axial Cr3+ ion lies above and below the triangular equatorial plane defined by the three Ln3+ ions. Magnetic measurements indicated that 1 and 2 exhibit single‐molecule magnetic behavior with Ea ≈ 14.1 K and τ0 = 4.2 × 10–8 s for 1 and Ea ≈ 13.0 K and τ0 = 6.4 × 10–7 s for 2. Interestingly, the clusters are soluble in aqueous solution. The two terminal water molecules of 1 can be substituted by two monocoordinated 4,4′‐dipyridyl N,N′‐dioxide (dpyo) molecules to afford [Dy3Cr2(HGly)6(dpyo)2(μ3‐OH)6(H2O)7]·(ClO4)9·15H2O (3) with a three‐dimensional cds network formed through π–π interactions. Magnetic analysis indicated that 3 also displays slow relaxation of the magnetization with Ea ≈ 13.24 K and τ0 = 9.16 × 10–8 s.
Asymmetric Synthesis of Crispine A: Constructing Tetrahydroisoquinoline Scaffolds Using Pummerer Cyclizations
Authors: Rotte Sateesh Chandra Kumar , Chittiboyina Amar G. , Khan Ikhlas A.
Published: August 2013

For the first time, a concise, linear and stereoselective synthesis of both enantiomers of the natural product crispine A has been achieved in six steps with an overall yield of ≥ 20 %, starting from commercially available veratraldehyde. Asymmetric Keck allylation and trifluoroacetic anhydride‐mediated Pummerer cyclization were the key transformations used to construct the tetrahydroisoquinoline core structure.
An Unusual and Diastereoselective Rearrangement during an Intramolecular Ene Reaction Involving a Disilane
Authors: Giros Audrey , Guillot Régis , Blanco Luis , Deloisy Sandrine
Published: August 2013

A chiral 1‐isopropenyl‐1‐(3‐oxopropyl)disilane derivative undergoes a type II ene reaction under Lewis acid catalyzed conditions to afford the silacyclic compound and an unexpected rearranged product with high diastereoselectivities. This rearrangement occurs through 1,2‐migration of a trimethylsilyl group. A common intermediate was proposed to explain the formation of both products.
Enhancement of thermostability and resistance against autolysis in a zinc metalloprotease
Authors: Shirdel S. Akram , Khajeh Khosro , Asghari S. Mohsen , Karbalaei‐Heidari Hamid‐Reza
Published: August 2013

Neutral proteases are inactivated at higher temperatures because of autolysis. It appears that autolysis involves some specific solvent‐exposed regions that become prone to local unfolding as temperature increases. Accordingly, we designed surface‐located mutations at the N‐terminal loops (A56P and T73F) of the neutral protease from Salinivibrio proteolyticus and compared the thermostability and autolysis as well as structural properties of wild‐type (WT) and mutant proteins. Circular dichroism in far‐UV region and intrinsic fluorescence data indicated that compactness of protein increases upon mutation. It was revealed that the catalytic efficiency (kcat/Km) of the enzyme is improved in mutants and optimum temperature of mutants increases relative to WT enzyme. It was also shown that the mutant enzymes are more resistant against autolysis and their thermostability and kinetic parameters are also changed compared to WT protein. This study shows that the stability of enzyme against autolysis and temperature may be increased even by changing only a single amino acid, which in turn is important from application point of view.
Model predictions of toxaphene degradation in the atmosphere over North America
Authors: Li R. , Jin J.
Published: August 2013

Technical toxaphene, a broad-spectrum pesticide mixture, degrades in the environment, resulting in potential changes in toxicity. The present study uses a multimedia model that the authors developed to estimate toxaphene degradation in the atmosphere over North America. The predicted degradation has strong spatial and temporal variability determined by processes such as emission and transport of technical toxaphene, as well as the complex interactions among many species (e.g., toxaphene, hydroxyl [OH] radicals, and ozone). More toxaphene is degraded in warmer months due to higher concentrations of technical toxaphene (primarily due to higher technical toxaphene emissions in the southeastern United States and transport to other regions) and OH radicals. In the model, OH radicals are created primarily through the reactions of water vapor with the excited oxygen atom, O(1D), generated by the photolysis of ozone, which is produced primarily by reactions of volatile organic compounds and nitrogen oxides (NOx) in the presence of sunlight. The higher OH concentrations in warmer months are primarily the result of higher solar radiation and ozone concentrations. The spatial distribution of degradation depends on the distribution of technical toxaphene soil residues as well as atmospheric transport and chemistry; significant chemical degradation occurs in the southeastern United States where soils are most heavily contaminated by past applications of toxaphene. Environ Toxicol Chem 2013;32:2663–2671. © 2013 SETAC
Effect of low concentration 17β-estradiol on the emissions of CH4 and CO2 in anaerobic sediments
Authors: Ruan Aidong , Zhao Ying , Liu Chenxiao , Wang Yuan , Xie Xianchuan
Published: August 2013

The estrogen17β-estradiol (E2) is one of the most widely distributed natural estrogens and is the most potent estrogen in the environment. For the present study, methanogenic bacteria communities were chosen as study objects to analyze the effects of E2 on the production of methane and carbon dioxide. Microecological systems in anaerobic pore water were constructed in the laboratory. The results show that E2 played an enhancing role in methanogenic activity when the concentrations were ≤0.5 ng/L. The enhancement was the strongest at 0.3 ng/L. However, when the E2 concentration exceeded 1.0 ng/L, it inhibited the methanogenic activities of bacteria. The inhibition effect persisted for up to 264 h, beyond which the trend became unclear. On the other hand, E2 has an inhibition effect on CO2 production in anaerobic sediments, which indicates that E2 had a significant inhibition effect on microbial activities under anaerobic conditions. Based on these experiments, the authors believe that E2 in anaerobic sediments can affect sediment microbial activities and therefore influence the self-purification of water bodies and methane ebullition. Environ Toxicol Chem 2013;32:2672–2677. © 2013 SETAC
Production of ferulic acid and coniferyl alcohol by conversion of eugenol using a recombinant strain of Saccharomyces cerevisiae
Authors: Lambert Fanny , Zucca Joseph , Ness Frédérique , Aigle Michel
Published: August 2013

We isolated an industrial strain of Saccharomyces cerevisiae 92411 able to convert coniferyl alcohol (2 g/l) into ferulic acid (1.8 g/l). To use eugenol as a substrate for the synthesis of natural ferulic acid, an optimized sequence of the Penicillium simplicissimum vaoA gene, encoding the flavoenzyme vanillyl‐alcohol oxidase (VAO), was expressed in the yeast 92411. To obtain a strong and stable expression of vaoA, an expression cassette flanked by Ty1 homologous sequences was constructed so the sequence encoding VAO could be integrated into various Ty1 loci of the host genome. The recombinant S. cerevisiae strain produced VAO. It synthesized ferulic acid directly from eugenol due to expression of the VAO activity and the natural ability of the strain to convert coniferyl alcohol into ferulic acid. In fermentation experiments, the strain produced up to 16.9 g/l of ferulic acid after 136 h. These results open new perspectives for the use of yeast biocatalysts in the biotechnological production of aromatic flavour from eugenol. Copyright © 2013 John Wiley & Sons, Ltd.
Partially Sulfonated Poly(1,4‐phenylene ether‐ether‐sulfone) and Poly(vinylidene fluoride) Blend Membranes for Fuel Cells
Authors: Unveren E. E. , Inan T. Y. , Çelebi S. S.
Published: August 2013

Blend membranes based on high conductive sulfonated poly(1,4‐phenylene ether‐ether‐sulfone) (SPEES) and poly(vinylidene fluoride) (PVDF) having excellent chemical stability were prepared and characterized for direct methanol fuel cells. The effects of PVDF content on the proton conductivity, water uptake, and chemical stability of SPEES/PVDF blend membranes were investigated. The morphology, miscibility, thermal, and mechanical properties of blend membranes were also studied by means of scanning electron microscopy (SEM), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and dynamic mechanical analysis (DMA) measurements. The blend membrane containing 90 wt.% SPEES (degree of sulfonation – DS = 72%) and 10 wt.% PVDF (Mw = 180,000) exhibits optimum properties among various SPEES72/PVDF membranes. Addition of PVDF enhanced resistance of the SPEES membrane against peroxide radicals and methanol significantly without deterioration of its proton conductivity. It's proton conductivity at 80 °C and 100% relative humidity is higher than Nafion 115 while it's methanol permeability is only half of that of Nafion 115 at 80 °C. The direct methanol fuel cell performance of the SPEES membranes was better than that of Nafion 115 membrane at 80 °C.
miRNA‐214 is related to invasiveness of human non‐small cell lung cancer and directly regulates alpha protein kinase 2 expression
Authors: Salim Hogir , Arvanitis Alexandros , de Petris Luigi , Kanter Lena , Hååg Petra , Zovko Ana , Özata Deniz Mahmut , Lui Weng‐Onn , Lundholm Lovisa , Zhivotovsky Boris , Lewensohn Rolf , Viktorsson Kristina
Published: August 2013

The prognosis of non‐small cell lung cancer (NSCLC) is poor, since it has often metastasized to distant organs by the time of diagnosis. Therefore, biomarkers predicting metastasis are crucial. miRNAs play important roles in the regulation of different tumor cell processes, including metastasis. We recently showed that miRNA‐214 is linked to a radioresistant phenotype of NSCLC. miRNA‐214 has been linked to metastasis in other tumor types. Therefore, we examined the role of miRNA‐214 in the metastatic potential of NSCLC. We showed that downregulation of miRNA‐214 increased invasive potential, and conversely, overexpression of miRNA‐214 decreased invasiveness of NSCLC cells in vitro. Gene expression and bioinformatic analyses of NSCLC cells with ablated miRNA‐214, identified a number of metastasis‐related target genes, including pregnancy‐associated plasma protein A (PAPP‐A), alpha protein kinase 2 (ALPK2), cyclin‐dependent kinase 6 (CDK6) and tumor necrosis‐factor alpha‐induced protein 3 (TNFAIP3). These were validated on mRNA and protein level to be regulated by miRNA‐214. Through immunoprecipitation we showed that only ALPK2 is directly regulated by miRNA‐214. We also examined the protein expression of these four genes in NSCLC tumors with respect to metastatic potential. These results showed that NSCLC tumors express these proteins at moderate‐high levels in the nucleus, cytoplasm and/or plasma membrane although with no significant correlation to the overall survival or the metastatic potential of the patients. However, we also showed that the membrane‐localized PAPP‐A had a higher expression level compared to the cytoplasm‐localized. In conclusion, we show that low miRNA‐214 expression is linked to a higher invasive potential of NSCLC cells. © 2013 Wiley Periodicals, Inc.
Evidence for tidal triggering of high‐amplitude rapid tremor reversals and tremor streaks in northern Cascadia
Authors: Thomas Trevor W. , Vidale John E. , Houston Heidi , Creager Kenneth C. , Sweet Justin R. , Ghosh Abhijit
Published: August 2013

We provide a new link between tectonic tremor propagation, tremor amplitude, and tidal stresses by analyzing high‐resolution tremor locations and amplitudes determined by multibeam backprojection of data from an array of subarrays. For two Cascadia episodic tremor and slip events, we observe repeating, high‐amplitude rapid tremor reversals (RTRs) and tremor streaks. They tend to occur when tremor amplitudes are highest and occur almost exclusively during periods of thrust‐encouraging, tidally induced shear stress on the fault. We speculate that thrust‐encouraging shear stress from tidal loading forces trigger RTRs and streaks that energetically rerupture the weakened fault behind the slow slip front. The high rate and amplitude of tremor during RTRs and streaks stands in contrast to the hypothesis that activity at the leading edge of the slow slip zone is the most energetic and loudest. This implies that the spatiotemportal pattern of slow earthquake slip migration is even more intricate than previously reported.
Using numerical modeling to explore the origin of intrusion patterns on Fernandina volcano, Galapagos Islands, Ecuador
Authors: Chestler Shelley R. , Grosfils Eric B.
Published: August 2013

Using parameterized finite element models, we investigate the emplacement of both radial and circumferential intrusions in the configuration observed at Fernandina volcano in the Galapagos Islands. When situated within the edifice at depths consistent with petrological and surface displacement data, inflation of a mildly oblate magma reservoir to the point of rupture can initiate either radial or circumferential intrusions in response to minor, volcanologically plausible variations in reservoir geometry (i.e., aspect ratio). In addition, more oblate reservoirs inject lateral sills into an inflation‐derived stress field consistent with rotation about their propagation axis to form gently dipping radial dikes, a mode of behavior recently inferred from InSAR data at Fernandina. All three styles of intrusion occur in near‐surface configurations consistent with field observations.
Designing biomarker studies for head and neck cancer
Authors: Kim Kelly Y. , McShane Lisa M. , Conley Barbara A.
Published: August 2013

Although there is ample literature reporting on the identification of molecular biomarkers for head and neck squamous cell carcinoma, none is currently recommended for routine clinical use. A major reason for this lack of progress is the difficulty in designing studies in head and neck cancer to clearly establish the clinical utility of biomarkers. Consequently, biomarker studies frequently stall at the initial discovery phase. In this article, we focus on biomarkers for use in clinical management, including selection of therapy. Using several contemporary examples, we identify some of the common deficiencies in study design that hinder success in biomarker development for this disease area, and we suggest some potential solutions. The purpose of this article is to provide guidance that can assist investigators to more efficiently move promising biomarkers in head and neck cancer from discovery to clinical practice. © 2013 Wiley Periodicals, Inc. Head Neck 36: 1069–1075, 2014
Raised serum ferritin concentration in hereditary hyperferritinemia cataract syndrome is not a marker for iron overload
Authors: Yin Dan , Kulhalli Vasu , Walker Ann P.
Published: August 2013

Hyperferritinemia and bilateral cataracts are features of the rare hereditary hyperferritinemia cataract syndrome (HHCS; OMIM #600886). HHCS is an autosomal dominant condition caused by mutations which increase expression of the ferritin light polypeptide (FTL) gene. We report a patient with HHCS who was misdiagnosed and treated as having hemochromatosis, in whom a heterozygous c.-160A>G mutation was identified in the iron responsive element (IRE) of FTL, causing ferritin synthesis in the absence of iron overload. This report demonstrates the need for clinical awareness of HHCS as a cause of hyperferritinemia in the absence of iron overload and provides a possible diagnostic schema. (HEPATOLOGY 2014;59:1204–1206)
Hepatic Oxidative Stress Activates the Gadd45b Gene by Way of Degradation of the Transcriptional Repressor STAT3
Authors: Kim Jung-Hwan , Qu Aijuan , Reddy Janardan K. , Gao Bin , Gonzalez Frank J.
Published: August 2013

Growth arrest and DNA damage-inducible beta (GADD45b) plays an important role in many intracellular events, such as cell cycle arrest, DNA repair, cell survival, apoptosis, and senescence. However, its mechanism of transcriptional regulation remains unclear. In this study the mechanism of peroxisome proliferator-activated receptor α (PPARα) ligand induction of the

Gadd45b

gene in mouse liver was investigated.

Gadd45b

messenger RNA (mRNA) was markedly induced by the PPARα agonist Wy-14,643 in wild-type mice but not in

Ppara

-null mice. Signal transducer and activator of transcription 3 (STAT3) was found to be a repressor of the

Gadd45b

gene through binding to upstream regulatory elements. The role of STAT3 in control of

Gadd45b

was confirmed using liver-specific

Stat3

-null mice. Wy-14,643 treatment stimulated STAT3 ubiquitination leading to activation of the

Gadd45b

gene as a result of loss of

Gadd45b

repression by STAT3. STAT3 degradation was induced by forced overexpression of the PPARα target gene-encoded enzyme ACOX1, which produces increased H2O2 as a byproduct of fatty acid β-oxidation. H2O2 also stimulated expression of

Gadd45b

in cultured cells.

Conclusion

: PPARα indirectly induces the

Gadd45b

gene in liver through promoting degradation of the repressor STAT3 as a result of elevated oxidative stress. (Hepatology 2014;59:695–704)
No Detectable Resistance to Tenofovir Disoproxil Fumarate After 6 Years of Therapy in Patients With Chronic Hepatitis B
Authors: Kitrinos Kathryn M. , Corsa Amoreena , Liu Yang , Flaherty John , Snow-Lampart Andrea , Marcellin Patrick , Borroto-Esoda Katyna , Miller Michael D.
Published: August 2013

One major challenge in the treatment of chronic hepatitis B is to maintain long-term viral suppression without promoting the selection of drug-resistant mutations. We analyzed data from 347 hepatitis B e antigen-negative and 238 hepatitis B e antigen-positive patients receiving tenofovir disoproxil fumarate (TDF) in an open-label, long-term extension of two phase 3 studies. To date, resistance analyses have been completed for patients receiving up to 288 weeks (6 years) of TDF. Population sequencing of hepatitis B virus (HBV) polymerase/reverse transcriptase (pol/RT) was attempted for all patients at baseline, and any patient who remained viremic (HBV DNA ≥400 copies/mL [≥69 IU/mL]) at week 288 or at the end of treatment with TDF (n = 52) or emtricitabine (FTC)/TDF (n = 7). Phenotypic analyses were performed in HepG2 cells using recombinant HBV containing patient pol/RT sequences. Approximately half of the patients on open-label treatment who qualified for genotyping had pol/RT sequence changes compared to baseline (23/52 [44%] on TDF, 4/7 [57%] on FTC/TDF). Most changes were at polymorphic sites and none were associated with TDF resistance. Virologic breakthrough occurred infrequently and was associated with nonadherence to study medication in the majority of cases (12/16, 75%). Per protocol, 57 patients (10%) were eligible to switch to FTC/TDF; the majority had HBV DNA <400 copies/mL at their last study visit regardless of whether they switched to FTC/TDF (n = 34) or maintained TDF monotherapy (n = 17). No patient exhibited persistent viremia (HBV DNA never <400 copies/mL) after week 240.

Conclusion

: TDF monotherapy maintains effective suppression of HBV DNA through 288 weeks of treatment with no evidence of TDF resistance. (Hepatology 2014;59:434–442)
Total Synthesis of a Pyrrolidin‐2‐one with the Structure Proposed for the Alkaloid Rigidiusculamide A
Authors: Radha Krishna Palakodety , Karunakar Reddy Bonepally
Published: August 2013

The total synthesis of the pyrrolidinone alkaloid rigidiusculamide A is reported starting from L‐tyrosine, using amidation, ring‐closing metathesis, and dihydroxylation as the key reactions.
Using response surfaces to estimate impacts of climate change on flood peaks: assessment of uncertainty
Authors: Kay A. L. , Crooks S. M. , Reynard N. S.
Published: August 2013

The potential impacts of climate change are an increasing focus of research, and ever‐larger climate projection ensembles are available, making standard impact assessments more onerous. An alternative way of estimating impacts involves response surfaces, which present the change in a given indicator for a large number of plausible climatic changes defined on a regular sensitivity domain. Sets of climate change projections can then be overlaid on the response surface and impacts estimated from the nearest corresponding points of the sensitivity domain, providing a powerful method for fast impact estimation for multiple projections and locations. However, the effect of assumptions necessary for initial response surface development must be assessed. This paper assesses the uncertainty introduced by use of a sensitivity framework for estimating changes in 20‐year return period flood peaks in Britain. This sensitivity domain involves mean annual and seasonal precipitation changes, and a number of simplifications were necessary for consistency and to reduce dimensionality. The effect of these is investigated for nine catchments across Britain, representing nine typical response surfaces (response types), using three sets of climate projections. The results show that catchments can have different causes of uncertainty and some catchments have an overall higher level of uncertainty than others. These differences are compatible with the underlying climatological and hydrological differences between the response types, giving confidence in generalization of the results. This enables the development of uncertainty allowances by response type, to be used alongside the response surfaces to provide more robust impact estimates. Copyright © 2013 John Wiley & Sons, Ltd.
Glioma‐derived galectin‐1 regulates innate and adaptive antitumor immunity
Authors: Verschuere Tina , Toelen Jaan , Maes Wim , Poirier Françoise , Boon Louis , Tousseyn Thomas , Mathivet Thomas , Gerhardt Holger , Mathieu Veronique , Kiss Robert , Lefranc Florence , Van Gool Stefaan W. , Vleeschouwer Steven De
Published: August 2013

Galectin‐1 is a glycan‐binding protein, which is involved in the aggressiveness of glioblastoma (GBM) in part by stimulating angiogenesis. In different cancer models, galectin‐1 has also been demonstrated to play a pivotal role in tumor‐mediated immune evasion especially by modulating cells of the adaptive immune system. It is yet unknown whether the absence or presence of galectin‐1 within the glioma microenvironment also causes qualitative or quantitative differences in innate and/or adaptive antitumor immune responses. All experiments were performed in the orthotopic GL261 mouse high‐grade glioma model. Stable galectin‐1 knockdown was achieved via transduction of parental GL261 tumor cells with a lentiviral vector encoding a galectin‐1‐targeting miRNA. We demonstrated that the absence of tumor‐derived but not of host‐derived galectin‐1 significantly prolonged the survival of glioma‐bearing mice as such and in combination with dendritic cell (DC)‐based immunotherapy. Both flow cytometric and pathological analysis revealed that the silencing of glioma‐derived galectin‐1 significantly decreased the amount of brain‐infiltrating macrophages and myeloid‐derived suppressor cells (MDSC) in tumor‐bearing mice. Additionally, we revealed a pro‐angiogenic role for galectin‐1 within the glioma microenvironment. The data provided in this study reveal a pivotal role for glioma‐derived galectin‐1 in the regulation of myeloid cell accumulation within the glioma microenvironment, the most abundant immune cell population in high‐grade gliomas. Furthermore, the prolonged survival observed in untreated and DC‐vaccinated glioma‐bearing mice upon the silencing of tumor‐derived galectin‐1 strongly suggest that the in vivo targeting of tumor‐derived galectin‐1 might offer a promising and realistic adjuvant treatment modality in patients diagnosed with GBM.
Effective targeting of chronic myeloid leukemia initiating activity with the combination of arsenic trioxide and interferon alpha
Authors: El Eit Rabab M. , Iskandarani Ahmad N. , Saliba Jessica L. , Jabbour Mark N. , Mahfouz Rami A. , Bitar Nizar M.A. , Ayoubi Hanadi R. El , Zaatari Ghazi S. , Mahon Francois‐Xavier , De Thé Hugues B. , Bazarbachi Ali A. , Nasr Rihab R.
Published: August 2013

Imatinib is the standard of care in chronic meloid leukemia (CML) therapy. However, imatinib is not curative since most patients who discontinue therapy relapse indicating that leukemia initiating cells (LIC) are resistant. Interferon alpha (IFN) induces hematologic and cytogenetic remissions and interestingly, improved outcome was reported with the combination of interferon and imatinib. Arsenic trioxide was suggested to decrease CML LIC. We investigated the effects of arsenic and IFN on human CML cell lines or primary cells and the bone marrow retroviral transduction/transplantation murine CML model. In vitro, the combination of arsenic and IFN inhibited proliferation and activated apoptosis. Importantly, arsenic and IFN synergistically reduced the clonogenic activity of primary bone marrow cells derived from CML patients. Finally, in vivo, combined interferon and arsenic treatment, but not single agents, prolonged the survival of primary CML mice. Importantly, the combination severely impaired engraftment into untreated secondary recipients, with some recipients never developing the disease, demonstrating a dramatic decrease in CML LIC activity. Arsenic/IFN effect on CML LIC activity was significantly superior to that of imatinib. These results support further exploration of this combination, alone or with imatinib aiming at achieving CML eradication rather than long‐term disease control.
High Expression of SGTA in Esophageal Squamous Cell Carcinoma Correlates With Proliferation and Poor Prognosis
Authors: Yang Xiaojing , Cheng Lei , Li Mei , Shi Hui , Ren Hanru , Ding Zongmei , Liu Fang , Wang Yuchan , Cheng Chun
Published: August 2013

Receptor tyrosine kinases (RTKs) expression and the growth factor such as platelet‐derived growth factor (PDGF) and their receptors have been considered relevant in the process of angiogenesis and dissemination in esophageal squamous cell carcinoma (ESCC). Small glutamine‐rich tetratricopeptide repeat‐containing protein alpha (SGTA) downstream of RTK signaling was a critical regulator of PDGF receptors (PDGFR) stability. The aim of the present study was to examine the expression of SGTA and to elucidate its clinicopathologic significance in ESCC. Immunohistochemistry and western blot analysis were performed for SGTA in ESCC samples. SGTA was up‐regulated in ESCC as compared with the adjacent normal tissue. High expression of SGTA was associated with tumor grade (P < 0.01), and SGTA was positively correlated with proliferation marker Ki‐67 (P < 0.05). Univariate analysis showed that SGTA expression did has a remarkable prediction for poor prognosis (P = 0.016). Knockdown or overexpression of SGTA affected ESCC cells proliferation and cell cycle. Additionally, after ESCC cells silenced for SGTA were treated with cisplatin (an anti‐ESCC agent), the cell growth was down‐regulated. These findings suggested that SGTA was involved in the pathogenesis of ESCC and might indicate a poor prognosis for ESCC patients. J. Cell. Biochem. 115: 141–150, 2014. © 2013 Wiley Periodicals, Inc.
Influence of Mg doping on the morphology and optical properties of ZnO films for enhanced H2sensing
Authors: Vijayalakshmi K. , Karthick K.
Published: August 2013

Highly oriented ZnO and Mg doped ZnO thin films were fabricated on Al2O3substrate by sputtering at room temperature. The effect of Mg doping on the structural, optical, and morphological properties of ZnO film was investigated. The intensity of (002) peak in X‐ray diffraction measurements revealed the influence of Mg doping on the crystallinity and orientation of ZnO film. Photoluminescence (PL) results show that the Ultraviolet (UV) emission peak was shifted to lower wavelength side for Mg:ZnO film indicating the possibility for quantum confinement. UV–vis–NIR optical absorption revealed an improvement in optical transmittance from 70 to 85%, and corresponding optical band gap from 3.25 to 3.54 eV. Atomic force microscope (AFM) images revealed the nano‐size particulate microstructure of the films. The surface topography of Mg doped ZnO film confirmed decreased grain size with large surface roughness and increased surface area, favorable for sensing. Pure ZnO and Mg doped ZnO film were used as active layer and tested for its sensing performance to hydrogen. Compared to undoped ZnO, 22 at.% Mg doped ZnO film showed much higher sensor response to H2at a concentration as low as 200 ppm and at a lower operating temperature of 180°C. A linear sensor response was observed for H2concentration in the range of 100–500 ppm.Microsc. Res. Tech. 76:1118–1124, 2013. © 2013 Wiley Periodicals, Inc.
Photoelectrons in the Enceladus plume
Authors: Coates A. J. , Wellbrock A. , Jones G. H. , Waite J. H. , Schippers P. , Thomsen M. F. , Arridge C. S. , Tokar R. L.
Published: August 2013

The plume of Enceladus is a remarkable plasma environment containing several charged particle species. These include cold magnetospheric electrons, negative and positive water clusters, charged nanograins, and “magnetospheric photoelectrons” produced from ionization of neutrals throughout the magnetosphere near Enceladus. Here we discuss observations of a population newly identified by the Cassini Plasma Spectrometer (CAPS) electron spectrometer instrument—photoelectrons produced in the plume ionosphere itself. These were found during the E19 encounter, in the energetic particle shadow where penetrating particles are absent. Throughout E19, CAPS was oriented away from the ram direction where the clusters and nanograins are observed during other encounters. Plume photoelectrons are also clearly observed during the E9 encounter and are also seen at all other Enceladus encounters where electron spectra are available. This new population, warmer than the ambient plasma population, is distinct from, but adds to, the magnetospheric photoelectrons. Here we discuss the observations and examine the implications, including the ionization source these electrons provide.
Role of atmospheric waves in the formation and maintenance of the Northern Annular Mode
Authors: Kuroda Yuhji , Mukougawa Hitoshi
Published: August 2013

We examined the roles of stationary, synoptic, and medium‐scale atmospheric waves in the formation and maintenance of the Northern Annular Mode (NAM) in winter by analyses of zonal momentum and wave energy based on six‐hourly reanalysis data from the European Centre for Medium‐range Weather Forecasts (ECMWF ERA‐Interim). Medium‐scale waves have periods shorter than about two days and their effect has been overlooked in previous research on the NAM. The effect of medium‐scale waves on the NAM is about 10% of that of total eddies. Although their effect on the NAM is of less importance than their effect on the Southern Annular Mode (SAM), it is still significant in the Northern Hemisphere. Our analysis also suggests that synoptic, medium‐scale, and stationary waves provide positive feedback to the zonal‐mean zonal wind of the NAM. In particular, energy transfer from synoptic and low‐frequency transient waves to stationary waves plays a key role in sustaining the stationary waves that drive zonal winds associated with the NAM.
Volatile organic compound distributions during the NACHTT campaign at the Boulder Atmospheric Observatory: Influence of urban and natural gas sources
Authors: Swarthout Robert F. , Russo Rachel S. , Zhou Yong , Hart Andrew H. , Sive Barkley C.
Published: August 2013

A comprehensive suite of volatile organic compounds (VOCs) was measured at the semirural Boulder Atmospheric Observatory (BAO) in northeast Colorado during the Nitrogen, Aerosol Composition, and Halogens on a Tall Tower (NACHTT) campaign during the winter of 2011. A signature of elevated nonmethane hydrocarbon (NMHC) mixing ratios was observed throughout the campaign. The C2‐C5 alkane mixing ratios were an order of magnitude greater than the regional background. Light alkane mixing ratios were similar to those at urban sites impacted by petrochemical industry emissions with ethane and propane reaching maximums of over 100 ppbv. The mean (± standard deviation) calculated total OH reactivity (7.0 ± 5.0 s−1) was also similar to urban sites. Analysis of VOC wind direction dependence, emission ratios with tracer compounds, and vertical profiles up to 250 m implicated regional natural gas production activities as the source of the elevated VOCs to the northeast of BAO and urban combustion emissions as the major VOC source to the south of BAO. Elevated acetonitrile and dimethyl sulfide mixing ratios were also associated with natural gas emissions. Fluxes of natural gas associated NMHCs were determined to estimate regional emission rates which ranged from 40 ± 14 Gg yr−1 for propane to 0.03 ± 0.01 Gg yr−1 for n‐nonane. These emissions have the potential to impact downwind air quality as natural gas associated NMHCs comprised ≈24% of the calculated OH reactivity. The measurements described here provide a baseline for determining the efficacy of future policies designed to control emissions from natural gas production activities.
Assessment of the ASCAT wind error characteristics by global dropwindsonde observations
Authors: Chou Kun‐Hsuan , Wu Chun‐Chieh , Lin Shu‐Zheng
Published: August 2013

This research focuses on assessing the accuracy of the advanced scatterometer (ASCAT) wind vector around tropical cyclones by using data from dropwindsondes deployed by the surveillance and reconnaissance flights during 2007–2010. There are 987 matching samples for the comparisons, with wind speed up to 50 m s−1. The bias and root‐mean‐square differences of wind speed between ASCAT and dropwindsonde data are −1.7 and 5.3 m s−1, respectively. Further analyses also indicate that large wind direction differences occur in the low wind speed regime, while large wind speed differences occur in the high wind speed regime. The accuracy of wind vector in weak wind speed and high wind speed regimes are significantly reduced in saturated regions, implying that the rain contamination issue still affects the accuracy of ASCAT wind retrieval. The wind vector in the medium wind speed regime has much better quality, in good agreement with the satellite's designed specification. The ASCAT wind data obviously contain negative wind speed bias, which grows larger as wind speed increases. A regression fit between ASCAT and dropwindsonde wind speed is adopted to correct the bias of the ASCAT wind speed. The error characteristics are largely determined by the magnitude of wind speed and moisture saturation which are highly variable around the storm. Nevertheless, results from this study suggest that ASCAT wind data of velocities measuring between 12 and 18 m s−1 are more reliable and can be applied to determine the radius of 34 knot winds, a critical parameter in operational tropical cyclone analysis.
Hepatitis B virus infection in clustering of infection in families with unfavorable prognoses in northwest China
Authors: Yang Yuan , Jin Li , He Ying‐Li , Wang Ke , Ma Xiao‐Hua , Wang Jing , Yan Zhi , Feng Yu‐Ling , Li Yong‐Qin , Chen Tian‐Yan , Liu Hong‐Li , Zhao Ying‐Ren
Published: August 2013

Hepatitis B virus (HBV) infection and its associated liver diseases have characteristics of familial clustering in China. However, the reasons for this are not understood fully. To address this issue, the prevalence HBV infection and the characteristics of unfavorable prognoses in clustering of infection in families in northwest China were investigated. Families with clustering of infection and unfavorable prognoses were enrolled, and general information and serum samples were collected. The clinical features and sequelae of HBV infection were compared among the blood relatives (including the first‐, second‐, and third‐degree blood relatives) and spouses using the chi‐square test or Fisher's exact test. A total of 102 clusterings of infection families with unfavorable prognoses were interviewed. In the first‐, second‐, and third‐degree blood relatives and spouses, the prevalences of cirrhosis of the liver were 29.2%, 11.9%, and 8.7%, respectively, while those of hepatocellular carcinoma (HCC) were 21.8%, 1.4%, and 4.3%, respectively (P < 0.05). The mean ages of the onset of cirrhosis of the liver in the first‐, second‐, and third‐degree blood relatives and spouses were 57 ± 9.91, 47 ± 9.96, 38 ± 10.35, and 57 ± 8.49 years, respectively, while the mean ages of the onset of HCC were 60 ± 7.92, 49 ± 8.57, 41 ± 3.54, and 50 ± 0 years, respectively, (P < 0.05). The first‐, second‐, and third‐degree blood relatives from clustering of infection in families with unfavorable prognoses had prevalences of cirrhosis or HCC in descending order of relationship. The findings suggest that genetic factors may be associated with a familial tendency for cirrhosis of the liver and HCC. J Med. Virol. 85:1893–1899, 2013. © 2013 Wiley Periodicals, Inc.
Uncertainty analysis of streamflow drought forecast using artificial neural networks and Monte‐Carlo simulation
Authors: Dehghani Majid , Saghafian Bahram , Nasiri Saleh Farzin , Farokhnia Ashkan , Noori Roohollah
Published: August 2013

In this research, two scenarios of drought forecast were studied. In the first scenario, the time series of monthly streamflow were converted into the Standardized Hydrological Drought Index (SHDI), a similar index to the well‐known Standardized Precipitation Index (SPI). Multi‐layer feed‐forward artificial neural network (FFANN) was trained with the SHDI time series to forecast the hydrological drought of Karoon River in southwestern Iran. In the second scenario, the time series of monthly streamflow discharge was forecasted directly and then converted to the SHDI. Principal component analysis (PCA) and forward selection (FS) techniques were applied to remove dependency of inputs and reduce the number of input variables, respectively. Moreover, uncertainty of SHDI and monthly streamflow discharge forecasts were investigated using a Monte‐Carlo simulation approach. Findings indicated that the results of the first scenario were considerably better than the second scenario and that the SHDI adequately forecasted hydrological drought. The Monte‐Carlo simulations demonstrated that all of forecasted values lie within the 95% confidence intervals.
A wavelet‐based multiple linear regression model for forecasting monthly rainfall
Authors: He Xinguang , Guan Huade , Zhang Xinping , Simmons Craig T.
Published: August 2013

In this article, a rainfall forecasting model using monthly historical rainfall data and climate indices is developed by incorporating the multi‐resolution analysis (MRA) and multiple linear regression (MLR) model. The monthly rainfall anomaly and large‐scale climate index time series are decomposed using MRA into a certain number of component subseries at different temporal scales. The hierarchical lag relationship between the rainfall anomaly and each potential predictor is identified by cross correlation analysis with a lag time of at least one month at different temporal scales. The components of predictor variables with known lag times are then screened with a stepwise linear regression algorithm to be selectively included into the final forecast model. This MRA‐based rainfall forecasting method is examined with 46 stations over South Australia, and compared to the traditional MLR model based on the original time series. The models are trained with data from the 1959–1995 period and then tested in the 1996–2008 period for each station. The performance is compared with observed rainfall values, and evaluated by common statistics of relative absolute error and correlation coefficient. The results show that the proposed MRA‐based model provides considerably more accurate monthly rainfall forecasts for all of the selected stations over South Australia than the traditional regression model. For the MRA‐based method, historical rainfall is consistently useful for all examined stations, while the large‐scale climate signals are only partly useful for some stations.
Tendon gradient mineralization for tendon to bone interface integration
Authors: Qu Jin , Thoreson Andrew R. , Chen Qingshan , An Kai‐Nan , Amadio Peter C. , Zhao Chunfeng
Published: August 2013

Tendon‐to‐bone integration is a great challenge for tendon or ligament reconstruction regardless of use of autograft or allograft tendons. We mineralized the tendon, thus transforming the tendon‐to‐bone into a “bone‐to‐bone” interface for healing. Sixty dog flexor digitorum profundus (FDP) tendons were divided randomly into five groups: (1) normal FDP tendon, (2) CaP (non‐extraction and mineralization without fetuin), (3) CaPEXT (Extraction by Na2HPO4 and mineralization without fetuin), (4) CaPFetuin (non‐extraction and mineralization with fetuin), and (5) CaPEXTFetuin (extraction and mineralization with fetuin). The calcium and phosphate content significantly increased in tendons treated with combination of extraction and fetuin compared to the other treatments. Histology also revealed a dense mineral deposition throughout the tendon outer layers and penetrated into the tendon to a depth of 200 µm in a graded manner. Compressive moduli were significantly lower in the four mineralized groups compared with normal control group. No significant differences in maximum failure strength or stiffness were found in the suture pull‐out test among all groups. Mineralization of tendon alters the interface from tendon to bone into mineralized tendon to bone, which may facilitate tendon‐to‐bone junction healing following tendon or ligament reconstruction. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1713–1719, 2013
Histological confirmation and biological significance of cartilage canals demonstrated using high field MRI in swine at predilection sites of osteochondrosis
Authors: Tóth Ferenc , Nissi Mikko J. , Zhang Jinjin , Benson Michael , Schmitter Sebastian , Ellermann Jutta M. , Carlson Cathy S.
Published: August 2013

Cartilage canal vessels in epiphyseal cartilage have a pivotal role in the pathogenesis of osteochondrosis/osteochondritis dissecans. The present study aimed to validate high field magnetic resonance imaging (MRI) methods to visualize these vessels in young pigs. Osteochondral samples from the distal femur and distal humerus (predilection sites of osteochondrosis) of piglets were imaged post‐mortem: (1) using susceptibility‐weighted imaging (SWI) in an MRI scanner, followed by histological evaluation; and (2) after barium perfusion using µCT, followed by clearing techniques. In addition, both stifle joints of a 25‐day‐old piglet were imaged in vivo using SWI and gadolinium enhanced T1‐weighted MRI, after which distal femoral samples were harvested and evaluated using µCT and histology. Histological sections were compared to corresponding MRI slices, and three‐dimensional visualizations of vessels identified using MRI were compared to those obtained using µCT and to the cleared specimens. Vessels contained in cartilage canals were identified using MRI, both ex vivo and in vivo; their locations matched those observed in the histological sections, µCT images, and cleared specimens of barium‐perfused tissues. The ability to visualize cartilage canal blood vessels by MRI, without using a contrast agent, will allow future longitudinal studies to evaluate their role in developmental orthopedic disease. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:2006–2012, 2013
Polymorphisms in BMP4 and FGFR1 genes are associated with fracture non‐union
Authors: Guimarães João Matheus , Guimarães Isabel Cristina do Val , Duarte Maria Eugenia Leite , Vieira Thays , Vianna Verônica Fernandes , Fernandes Marco Bernardo Cury , Vieira Alexandre Rezende , Casado Priscila Ladeira
Published: August 2013

Fracture healing is a complex process influenced by a multitude of factors and expression of several thousand genes. Polymorphisms in these genes can lead to an extended healing process and explain why certain patients are more susceptible to develop non‐union. A total of 16 SNPs within five genes involved in bone repair pathogenesis (FAM5C, BMP4, FGF3, FGF10, and FGFR1) were investigated in 167 patients with long bone fractures, 101 with uneventful healing, and 66 presenting aseptic non‐unions. Exclusion criteria were patients presenting pathological fractures, osteoporosis, hypertrophic and infected non‐unions, pregnancy, and children. All genetic markers were genotyped using TaqMan real‐time PCR. Chi‐square test was used to compare genotypes, allele frequencies, and haplotype differences between groups. Binary logistic regression analyzed the significance of many covariates and the incidence of non‐union. Statistical analysis revealed open fracture to be a risk factor for non‐union development (p < 0.001, OR 3.6 [1.70–7.67]). A significant association of haplotype GTAA in BMP4 (p = 0.01) and FGFR1 rs13317 (p = 0.005) with NU could be observed. Also, uneventful healing showed association with FAM5C rs1342913 (p = 0.04). Our work supported the role of BMP4 and FGFR1 in NU fracture independently of the presence of previously described risk factors. © 2013 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 31:1971–1979, 2013
Genotypic variation in foliar nutrient concentrations, δ13C, and chlorophyll fluorescence in relation to tree growth of radiata pine clones in a serpentine soil
Authors: Xue Jianming , Clinton Peter W. , Davis Murray R. , Siddiqui Tahir , Beets Peter N. , Leckie Alan C.
Published: August 2013

This study investigated the genotypic variation in foliar nutrient concentrations, isotopic signature (δ13C), and chlorophyll fluorescence (Fv/Fm) and tree growth of 40 radiata pine clones grown on a New Zealand serpentine soil, and the relationships between growth and physiological traits of these clones from improved and unimproved groups. Genotypic variation in growth and physiological traits existed within (i.e., clonal) and between groups, with larger variation among clones. The clonal repeatabilities were greater for foliar nitrogen (N), calcium (Ca), magnesium (Mg), boron (B) concentrations, δ13C, and Ca : Mg ratio (0.35–0.64) than for growth traits (0.14–0.27) and other physiological traits (0.08–0.24). Significant phenotypic correlations were found between growth traits and foliar phosphorus (P), potassium (K), sulfur (S), iron (Fe), and K : Mg and Ca : Mg ratios and Fv/Fm (positive), and foliar Mg (negative). This study indicates that the trees on this serpentine soil generally suffered from multiple nutrient deficiencies and imbalances and the clonal variation in growth performance was more related to their capabilities of acclimation to nutrient than water stresses. Overall, the clones that absorbed more P, K, S, and Fe and less Mg from the soil grew better on this serpentine soil. For unimproved clones, the most limiting nutrients for tree growth were foliar K and Fe, while for improved clones it was foliar K.