bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of metabolites in WZS‐miniature pig urine after oral administration of Danshen decoction by HPLC coupled with diode array detection with electrospray ionization tandem ion trap and time‐of‐flight mass spectrometry
Authors: Zhao Xin , Yang Dong‐Hui , Zhou Qi‐Le , Xu Feng , Zhang Lei , Liang Jing , Liu Guang‐Xue , Cai Shao‐Qing , Yang Xiu‐Wei 
Published: December 2012

ABSTRACTDanshen (DS) is a widely used traditional Chinese medicine for treating cardiovascular and cerebrovascular diseases. A simple, rapid and sensitive method was developed for identification of the in vivo metabolites in urine of WZS‐miniature pigs after oral administration of DS decoction by HPLC coupled with diode array detection with electrospray ionization tandem ion trap and time‐of‐flight mass spectrometry. This method has been successfully applied to simultaneous identification of 50 compounds (including 11 new ones) in pig urine. In addition, one new compound, (3‐hydroxyphenyl) crylic acid glycine methyl ester (C1), along with eight known ones were first isolated by column chromatography and identified by spectroscopic means, including 1D/2DNMR and mass spectrometry, as reference substances. Ten phenolic compounds (protocatechuic aldehyde, protocatechuic acid, caffeic acid, danshensu, ferulic acid, isoferulic acid, rosmarinic acid and salvianolic acid A/B/D) were found to be the main absorbed original constituents of DS decoction, which underwent the metabolic reactions of glucuronidation, sulfation, methylation, hydrogenation and glycine conjugation in vivo. In conclusion, the developed method is applicable to the analysis and identification of constituents in biological matrices after administration of DS decoction. Copyright © 2012 John Wiley & Sons, Ltd.
Does modern high standard life style cause type 1 diabetes in children?
Authors: Ludvigsson Johnny , Holmqvist Britt‐Marie , Samuelsson Ulf 
Published: December 2012

AbstractBackgroundType 1 diabetes is a serious disease which, in spite of intensive treatment, causes serious complications and increased mortality. The incidence is increasing, but the aetiology is unknown. As part of modern lifestyle, increased hygiene has been suspected as one contributing cause but so far there is no evidence. Several large epidemiological studies, mainly restricted to children with increased genetic risk for type 1 diabetes, have so far given no clue.MethodsAll Babies in Southeast Sweden is unique in its design as it has followed an unselected group of children from birth 1997–1999 and onwards with regular follow‐ups. This report is based on questionnaires from initially 16 051 children of whom 80 have later on developed type 1 diabetes. The parents answered questionnaires at the birth of their child and then after 1, 2–3, 5–6 and 8 years. A number of parameters possibly related to hygiene were analysed with several statistical methods, both with univariate and in regression models.ResultsOur study cannot identify any crucial environmental factor. This indicates that hygiene‐related parameters traditionally regarded as part of ‘modern life style’ do not play any important role for the aetiology of type 1 diabetes.ConclusionsThere is no reason to recommend a change of that part of our lifestyle. We find weak associations to previous gastrointestinal infections, which gives a hint that development of type 1 diabetes may be related to problems in the gut and maybe one should look closer into the microbes living in the gut. Copyright © 2012 John Wiley & Sons, Ltd.
Insulin secretion is increased in non‐diabetic subjects with fasting hypertriglyceridaemia
Authors: Simental‐Mendía Luis E. , Rodríguez‐Morán Martha , Simental‐Saucedo Luis , Guerrero‐Romero Fernando 
Published: December 2012

AbstractBackgroundThe elevation of triglycerides is strongly linked with insulin resistance, but it has not been evaluated in relationship to insulin secretion. The aim of this study was to determine whether hypertriglyceridaemia is associated with abnormal insulin secretion.MethodsA cross‐sectional study was carried out. Eligible subjects, apparently healthy men and non‐pregnant women aged 20–65 years were recruited. According to the triglyceride levels, subjects were allocated in the groups with hypertriglyceridaemia and normotriglyceridaemia. Hypertriglyceridaemia was defined by serum triglyceride levels ≥150 mg/dL. Insulin secretion was evaluated by the first phase of insulin secretion (1st PIS) and the second phase of insulin secretion (2nd PIS). A regression linear analysis was performed to evaluate the association between hypertriglyceridaemia (independent variable) and the first and second phase insulin secretion (dependent variables).ResultsA total of 247 apparently healthy subjects were enrolled; 113 (45.7%) with hypertriglyceridaemia and 134 (54.3%) in the control group. The simple regression linear analysis showed a significant association between hypertriglyceridaemia and the 1st PIS [B = 207.0; 95% confidence interval (CI) 33.5–380.5, p = 0.02] and the 2nd PIS (B = 48.7; 95% CI 9.2–88.2, p = 0.01). A multiple regression linear analysis adjusted by age, sex, body mass index and waist circumference was performed showing that fasting hypertriglyceridaemia remained significantly associated with the 1st PIS (B = 184.3; 95% CI 13.0–355.7, p = 0.03) and the 2nd PIS (B = 43.1; 95% CI 4.2–81.9, p = 0.03).ConclusionsThe results of this study show that hypertriglyceridaemia is associated with the increase of the 1st PIS and the 2nd PIS in apparently healthy subjects. Copyright © 2012 John Wiley & Sons, Ltd.
Water use characteristics of black mangrove (Avicennia germinans) communities along an ecotone with marsh at a northern geographical limit
Authors: Krauss Ken W. , McKee Karen L. , Hester Mark W. 
Published: December 2012

ABSTRACTMangroves are expanding into warm temperate‐zone salt marsh communities in several locations globally. Although scientists have discovered that expansion might have modest effects on ecosystem functioning, water use characteristics have not been assessed relative to this transition. We measured early growing season sapflow (Js) and leaf transpiration (Tr) in Avicennia germinans at a latitudinal limit along the northern Gulf of Mexico (Louisiana, United States) under both flooded and drained states and used these data to scale vegetation water use responses in comparison with Spartina alterniflora. We discovered strong convergence when using either Js or Tr for determining individual tree water use, indicating tight connection between transpiration and xylem water movement in small Avicennia trees. When Tr data were combined with leaf area indices for the region with the use of three separate approaches, we determined that Avicennia stands use approximately 1·0–1·3 mm d–1 less water than Spartina marsh. Differences were only significant with the use of two of the three approaches, but are suggestive of net conservation of water as Avicennia expands into Spartina marshes at this location. Average Js for Avicennia trees was not influenced by flooding, but maximum Js was greater when sites were flooded. Avicennia and Spartina closest to open water (shoreline) used more water than interior locations of the same assemblages by an average of 1·3 mm d−1. Lower water use by Avicennia may indicate a greater overall resilience to drought relative to Spartina, such that aperiodic drought may interact with warmer winter temperatures to facilitate expansion of Avicennia in some years. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Slow Self‐Assembly Favors Hysteresis above Room Temperature for an Iron(II) 1D‐Chain Spin‐Crossover Complex
Authors: Nowak René , Bauer Wolfgang , Ossiander Tanja , Weber Birgit 
Published: December 2012

AbstractThe X‐ray structures and magnetic properties of three new iron(II) coordination polymers with the general formula [FeL1(Lax)]n are presented. L1 is the tetradentate N2O22– Schiff‐base‐like ligand (E,E)‐{dimethyl‐2,2′‐[1,2‐phenylenebis(iminomethylidyne)]bis(3‐oxobutanato)(2–)‐N,N′,O3,O3′}. For the axial coordination, 4,4′‐bipyridine (bipy), 1,2‐bis(4‐pyridyl)ethane (bpea), and 1,2‐bis(4‐pyridyl)ethene (bpee) were used. Spin‐transition behavior was observed for the bpea and the bipy complexes. In both cases, two different polymorphs were isolated, showing different magnetic properties. In the case of the bipy complex 1, different preparation methods were tested to elucidate which conditions favor one polymorph over another. It appears that a slow precipitation of the coordination polymer favors a cooperative spin transition above room temperature, whereas a fast precipitation results in a gradual spin transition at lower temperatures. In the case of the bpea complex, an incomplete spin transition is observed, which can be explained by the crystal packing.
Effect of Spin‐Crossover‐Induced Pore Contraction on CO2–Host Interactions in the Porous Coordination Polymers [Fe(pyrazine)M(CN)4] (M = Ni, Pt)
Authors: Culp Jeffrey T. , Chen De‐Li , Liu Jinchen , Chirdon Danielle , Kauffman Kristi , Goodman Angela , Johnson J. Karl 
Published: December 2012

AbstractVariable‐temperature in situ ATR‐FTIR spectra are presented for the porous spin‐crossover compounds [Fe(pyrazine)Ni(CN)4] and [Fe(pyrazine)Pt(CN)4] under CO2 pressures of up to 8 bar. Significant shifts in the ν3 and ν2 IR absorption bands of adsorbed CO2 are observed as the host materials undergo transition between low‐ and high‐spin states. Computational models used to determine the packing arrangement of CO2 within the pore structures show a preferred orientation of one of the adsorbed CO2 molecules with close O=C=O···H contacts with the pyrazine pillar ligands. The interaction is a consequence of the commensurate distance of the inter‐pyrazine separations and the length of the CO2 molecule, which allows the adsorbed CO2 to effectively bridge the pyrazine pillars in the structure. The models were used to assign the distinct shifts in the IR absorption bands of the adsorbed CO2 that arise from changes in the O=C=O···H contacts that strengthen and weaken in correlation with changes in the Fe–N bond lengths as the spin state of Fe changes. The results indicate that spin‐crossover compounds can function as a unique type of flexible sorbent in which the pore contractions associated with spin transition can affect the strength of CO2–host interactions.
Samarium Diiodide Promoted Reduction of 3,6‐Dihydro‐2H‐1,2‐oxazines: Competition of 1,4‐Amino Alcohol Formation and Ring Contraction to Pyrrole Derivatives
Authors: Jasiński Marcin , Watanabe Toshiko , Reissig Hans‐Ulrich 
Published: December 2012

AbstractAn approach to enantiopure 1,4‐amino alcohols of type 4 by samarium diiodide mediated N–O cleavage of 3,6‐dihydro‐2H‐1,2‐oxazines 3 is presented. In several cases we observed the formation of 3‐methoxypyrrole derivatives 5 as byproducts in significant amounts. For 1,2‐oxazine derivative syn‐3a, up to 27 % of pyrrole 5a was isolated. The examples presented show a strong dependence of the chemoselectivity on the structure of the precursor 1,2‐oxazines. The formation of pyrroles 5 as side‐products is rationalized by a competitive intramolecular hydrogen shift of the initially formed ring cleavage intermediate B to C and subsequent cyclization of aldehyde E to afford F. This pathway can be disfavoured when a higher excess of samarium diiodide was employed, which generally provided the 1,4‐amino alcohols 4 in good yields.
High‐Throughput Mercury Monitoring in Indoor Dust Microsamples by Bath Ultrasonic Extraction and Anodic Stripping Voltammetry on Gold Nanoparticles‐Modified Screen‐Printed Electrodes
Authors: Bernalte E. , Marín Sánchez C. , Pinilla Gil E. 
Published: December 2012

AbstractA simple strategy based on the combination of a high‐throughput bath ultrasonic extraction with portable electrochemical determination was developed for fast Hg(II) monitoring in dust samples, with potential applicability to decentralized atmospheric pollution assessment. Square‐wave anodic stripping voltammetry (SWASV) on gold nanoparticles‐modified screen‐printed carbon electrodes (AuNPs‐SPCEs) coupled to the extraction procedure resulted in a convenient method for sensitive, reliable, and reproducible mercury detection. The proposed combination of techniques was evaluated with good agreement by using NIST Standard Reference Material 2583 Trace Elements in Indoor Dust. The method was successfully applied for Hg monitoring in complex and heterogeneous indoor dust samples collected at different indoor ambients. ICP‐MS was used to contrast the voltammetric measurements.
Voltammetric Determination of Trace Amounts of 2‐Aminofluoren‐9‐one at a Mercury Meniscus Modified Silver Solid Amalgam Electrode
Authors: Hájková Andrea , Hraníček Jakub , Barek Jiří , Vyskočil Vlastimil 
Published: December 2012

AbstractVoltammetric behavior of the genotoxic environmental pollutant 2‐aminofluoren‐9‐one (2‐AFN) was investigated using direct current voltammetry (DCV), differential pulse voltammetry (DPV) and adsorptive stripping differential pulse voltammetry (AdSDPV) at a mercury meniscus modified silver solid amalgam electrode (m‐AgSAE). Optimum conditions were found for its DCV and DPV determination in a methanolBrittonRobinson buffer pH 4.0 (1 : 9, v/v) medium (in a concentration range from 0.1 to 100 µmol L−1 of 2‐AFN) and for its AdSDPV determination in a 0.2 mol L−1 acetate buffer pH 4.0 medium (from 0.01 to 0.1 µmol L−1 of 2‐AFN), with limits of quantification (LQs) of 0.2, 0.1 and 0.005 µmol L−1 for DCV, DPV and AdSDPV, respectively. For comparison, the UV spectrophotometric (measured at 274 nm) and fluorimetric (measured at 460 nm, using the excitation wavelength of 314 nm) determination of 2‐AFN were carried out in methanol, with LQs of 0.1 and 2 µmol L−1, respectively. Practical applicability of the newly developed voltammetric methods was verified on direct determination of 2‐AFN in model samples of drinking and river water, with the lowest LQs in the range of 5–10 nmol L−1.
Comparison of Glucose Oxidation by Crosslinked Redox Polymer Enzyme Electrodes Containing Carbon Nanotubes and a Range of Glucose Oxidising Enzymes
Authors: MacAodha Domhnall , Ó Conghaile Peter , Egan Brenda , Kavanagh Paul , Sygmund Christoph , Ludwig Roland , Leech Dónal 
Published: December 2012

AbstractThe sugar oxidising enzymes glucose oxidase, glucose dehydrogenases (GDH) and cellobiose dehydrogenases (CDH) were co‐immobilised, in the presence of multiwalled carbon nanotubes, with osmium redox polymers. Under pseudo‐physiological conditions of 5 mM glucose, 150 mM NaCl, 37 °C, glucose oxidation current densities above 800 µA cm−2 are obtained from films containing an [Os(4,4′‐dimethyl‐2,2′‐bipyridine)2(poly‐vinylimidazole)10Cl]+ redox polymer, redox potential 0.1 V vs. Ag/AgCl, and either glucose oxidase or FAD‐dependant GDH. Current produced by, and stability of, glucose‐oxidising half‐cells is compared in 100 mM glucose, with films containing CDHs proving most stable. Such results show promise for development of glucose‐oxidising enzymatic fuel cells.
Myristoylated PreS1-domain of the hepatitis B virus L-protein mediates specific binding to differentiated hepatocytes
Authors: Meier Anja , Mehrle Stefan , Weiss Thomas S. , Mier Walter , Urban Stephan 
Published: December 2012

Abstract

Chronic infection with the human hepatitis B virus (HBV) is a global health problem and a main cause of progressive liver diseases. HBV exhibits a narrow host range, replicating primarily in hepatocytes. Both host and hepatocyte specificity presumably involve specific receptor interactions on the target cell; however, direct evidence for this hypothesis is missing. Following the observation that HBV entry is specifically blocked by L-protein-derived preS1-lipopeptides, we visualized specific HBV receptor/ligand complexes on hepatic cells and quantified the turnover kinetics. Using fluorescein isothiocyanate-labeled, myristoylated HBV preS1-peptides we demonstrate (1) the presence of a highly specific HBV receptor on the plasma membrane of HBV-susceptible primary human and tupaia hepatocytes and HepaRG cells but also on hepatocytes from the nonsusceptible species mouse, rat, rabbit and dog; (2) the requirement of a differentiated state of the hepatocyte for specific preS1-binding; (3) the lack of detectable amounts of the receptor on HepG2 and HuH7 cells; (4) a slow receptor turnover at the hepatocyte membrane; and (5) an association of the receptor with actin microfilaments. The presence of the preS1-receptor in primary hepatocytes from some non-HBV-susceptible species indicates that the lack of susceptibility of these cells is owed to a postbinding step. Conclusion: These findings suggest that HBV hepatotropism is mediated by the highly selective expression of a yet unknown receptor* on differentiated hepatocytes, while species specificity of the HBV infection requires selective downstream events, e.g., the presence of host dependency or the absence of host restriction factors. The criteria defined here will allow narrowing down reasonable receptor candidates and provide a binding assay for HBV-receptor expression screens in hepatic cells. (HEPATOLOGY 2013)
Bile salt export pump is dysregulated with altered farnesoid X receptor isoform expression in patients with hepatocellular carcinoma
Authors: Chen Yuan , Song Xiulong , Valanejad Leila , Vasilenko Alexander , More Vijay , Qiu Xi , Chen Weikang , Lai Yurong , Slitt Angela , Stoner Matthew , Yan Bingfang , Deng Ruitang 
Published: December 2012

Abstract

As a canalicular bile acid effluxer, the bile salt export pump (BSEP) plays a vital role in maintaining bile acid homeostasis. BSEP deficiency leads to severe cholestasis and hepatocellular carcinoma (HCC) in young children. Regardless of the etiology, chronic inflammation is the common pathological process for HCC development. Clinical studies have shown that bile acid homeostasis is disrupted in HCC patients with elevated serum bile acid level as a proposed marker for HCC. However, the underlying mechanisms remain largely unknown. In this study, we found that BSEP expression was severely diminished in HCC tissues and markedly reduced in adjacent nontumor tissues. In contrast to mice, human BSEP was regulated by farnesoid X receptor (FXR) in an isoform-dependent manner. FXR-α2 exhibited a much more potent activity than FXR-α1 in transactivating human BSEP

in vitro

and

in vivo

. The decreased BSEP expression in HCC was associated with altered relative expression of FXR-α1 and FXR-α2. FXR-α1/FXR-α2 ratios were significantly increased, with undetectable FXR-α2 expression in one third of the HCC tumor samples. A similar correlation between BSEP and FXR isoform expression was confirmed in hepatoma Huh7 and HepG2 cells. Further studies showed that intrahepatic proinflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α), were significantly elevated in HCC tissues. Treatment of Huh7 cells with IL-6 and TNF-α resulted in a marked increase in FXR-α1/FXR-α2 ratio, concurrent with a significant decrease in BSEP expression.

Conclusion

: BSEP expression is severely diminished in HCC patients associated with alteration of FXR isoform expression induced by inflammation. Restoration of BSEP expression through suppressing inflammation in the liver may reestablish bile acid homeostasis.
Incorporation of fibronectin to enhance cytocompatibility in multilayer elastin‐like protein scaffolds for tissue engineering
Authors: Ravi Swathi , Caves Jeffrey M. , Martinez Adam W. , Haller Carolyn A. , Chaikof Elliot L. 
Published: December 2012

AbstractRecombinant, elastin‐like protein (ELP) polymers are of significant interest for the engineering of compliant, resilient soft tissues due to a wide range of tunable mechanical properties, biostability, and biocompatibility. Here, we enhance endothelial cell (EC) and mesenchymal stem cell compatibility with ELP constructs by addition of fibronectin (Fn) to the surface or bulk of ELP hydrogels. We find that cell adhesion, proliferation, and migration can be modulated by Fn addition. Adsorption of Fn to the hydrogel surface is more efficient than bulk blending. Surface immobilization of Fn by genipin crosslinking leads to stability without loss of bioactivity. Gels of varying mechanical modulus do not alter cell adhesion, proliferation, and migration in the range we investigate. However, more compliant gels promote an EC morphology suggesting tubulogenesis or network formation, whereas stiffer gels promote cobblestone morphology. Multilayer structures consisting of thin ELP sheets reinforced with collagen microfiber are fabricated and laminated through the culture of MSCs at layer interfaces. High cell viability in the resulting three‐dimensional constructs suggests the applicability of Fn to the design of strong, resilient artificial blood vessels and other soft tissue replacements. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Bioactivity and hemocompatibility study of amorphous hydrogenated carbon coatings produced by pulsed magnetron discharge
Authors: Lopez‐Santos C. , Colaux J. L. , Laloy J. , Fransolet M. , Mullier F. , Michiels C. , Dogné J.‐M. , Lucas S. 
Published: December 2012

AbstractLiterature contains very few data about the potential biomedical application of amorphous hydrogenated carbon (a‐C:H) thin films deposited by reactive pulsed magnetron discharge even so it is one of the most scalable plasma deposition technique. In this article, we show that such a C2H2 pulsed magnetron plasma produces high quality coating with good hemocompatibility and bioactive response: no effect on hemolysis and hemostasis were observed, and proliferation of various cell types such as endothelial, fibroblast, and osteoblast‐like cells was not affected when the deposition conditions were varied. Cell growth on a‐C:H coatings is proposed to take place by a two‐step process: the initial cell contact is affected by the smooth topography of the a‐C:H coatings, whereas the polymeric‐like structure, together with a moderate hydrophilicity and a high hydrogen content, directs the posterior cell spreading while preserving the hemocompatible behavior. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Early healing in alveolar sockets grafted with titanium granules. An experimental study in a dog model
Authors: Arruda Thiago , Sukekava Flávia , de Souza André B. , Rasmusson Lars , Araújo Maurício G. 
Published: December 2012

AbstractThe aim of the present study was to evaluate the effect of the placement of titanium granules in fresh extraction sockets on early bone formation. The mesial roots of the third maxillary premolars of five adult beagle dogs were removed. On one side of the maxilla (Test group) the fresh extraction socket was grafted with titanium granules, while the contra‐lateral socket was left non‐grafted (Control group). After 1 month of healing, the dogs were euthanized and biopsies were obtained. The healing tissues were described, and histometric measurements were performed to obtain the percentage area occupied by connective tissue, new mineralized bone, bone marrow, and biomaterial particles. After 1 month of healing the findings from the histological examination revealed the titanium graft to be well incorporated into the provisional connective tissue or newly formed woven bone. The histometric measurements showed, however, that less mineralized bone was formed in the Test group than in the Control group. The present study suggests that the use of titanium granules in fresh extraction sockets was conducive to new bone formation. The graft of titanium granules seems, however, to delay the early phase of the healing process. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.