bluuebunny/crossref_metadata_2025_split huggingface dataset:
Calorimetric Study and Thermal Analysis of 4‐(Aminomethyl) Benzoic Acid
Authors: ZHENG Qingyun , TAN Zhicheng , WANG Difan , HAO Aiping , LIU Beiping , LÜ Xuechuan , SHI Quan 
Published: May 2009

AbstractMolar heat capacities of 4‐(aminomethyl)benzoic acid were precisely measured with a small sample precision automated adiabatic calorimeter over the temperature range from 80 to 400 K, and the heat capacity data were fitted to a polynomial equation:Cp,m=162.01+91.771X+6.4372X2+1.7517X3−4.991X4+8.909X5+1.585X6,X= (T−235)/155. The constant‐volume energy of combustion of the compound was measured by means of a precision oxygen bomb combustion calorimeter. The standard enthalpy values of combustion and formation were determined to be: ΔcHm⊖= − (4300±4) kJ·mol−1and ΔfHm⊖= −(420±5) kJ·mol−1.
Molal Enthalpy of Solution of Ionic Liquid [C2mim][GaCl4]
Authors: GUAN Wei , LIU Li , WANG Caixia , YANG Jiazhen 
Published: May 2009

AbstractAn ionic liquid (IL), [C2mim][GaCl4] (1‐ethyl‐3‐methylimidazolium chlorogallate), was prepared by directly mixing 1‐ethyl‐3‐methylimidazolium chloride ([C2mim][Cl]) and anhydrous GaCl3 with a molar ratio of 1/1 under dry argon. The molal enthalpies of solution, ΔsHm, of [C2mim][GaCl4], were measured over a molality range of about 0.008–0.1 mol·kg−1 by a solution reaction isoperibol calorimeter at 298.15 K. Considering the hydrolization of anion [GaCl4]− in dissolution process of the IL, a new method of determining the standard molal enthalpy of solution, ΔsHm⊖, was put forward on the basis of Pitzer's mixed electrolyte solution theory so that ΔsHm⊖=−132 kJ·mol−1 and the sum of Pitzer's parameters: 4βGa,Cl(0)+4β[C2mim],Cl(0)+4Ca,[C2mim]=−0.1373076, βGa,Cl(1)L+β(1)L=0.3484209 were obtained. In terms of thermodynamic cycle and Glasser's theory of lattice energy for IL, the dissociation enthalpy of [GaCl4]−(g), ΔHdis([GaCl4]−)≈5855 kJ·mol−1, that is enthalpy change for the reaction: [GaCl4]−(g)→Ga3+(g)+4Cl−(g), was estimated.
Silver(I) Coordination Polymers of 2,11‐Dithia[3.3]paracyclophane and in situ Silver(I) Perfluoro‐dicarboxylates
Authors: LIU Shuqin , ZHANG Xiongfu , WANG Huilong , MENG Changgong , MOU Wensheng 
Published: May 2009

AbstractCoordination polymers of 2,11‐dithia[3.3]paracyclopane (dtpcp) with in situ silver(I) perfluoro‐dicarboxylates characterized by single crystal X‐ray analysis are described. Their structures were found to strongly depend on the dicarboxylates. With disilver(I) tetrafluoro‐succinate [(CF2)n(COOAg)2, n=2], a 1D chain of [Ag4(dtpcp)3‐ (C2F4(CO2)2)2]·2CH3OH (1) forms in which two silver(I) ions link with two dtpcp ligands to afford a four‐numbered ring and disilver(I) tetrafluoro‐succinates link such rings. Changing the silver salt to disilver(I) hexafluoroglutarate [(CF2)n(COOAg)2, n=3] produces a 3D structure with composition of [Ag2(dtpcp)(C3F6(CO2)2)] (2), in which the disilver(I) hexafluoroglutarates connect with each other to form a 1D S‐shape chain and dtpcp ligands bridge such chains to give a 3D internet. With disilver(I) octafluoroadipate [(CF2)n(COOAg)2, n=4], 2D porous sheets of [Ag2(dtpcp)2(C4F8(CO2)2)]·2mesitylene (3) are formed. In polymer 3 four dtpcp and two octafluoroadipates are linked together by silver(I) ions to give a cavity in which two guest mesitylene molecules are located.
Effect of Pb2+ on the Kinetic and Spectral Characterization of Ribulose‐1,5‐bisphosphate Carboxylase/Oxygenase
Authors: WANG Xuming , ZE Yuguan , WU Xiao , CHEN Liang , HUANG Hao , LIU Jie , MA Linglan , HONG Fashui 
Published: May 2009

Abstract Pb2+ at various concentrations was added to the purified ribulose‐1,5‐bisphosphate carboxylase/oxygenase (rubisco, E.C.4.1.1.39) in vitro to gain insight into the mechanism of molecular interactions between Pb2+ and rubisco using spectral methods. It was found that the carboxylase activity of rubisco gradually decreased with increasing concentrations of Pb2+. The kinetics constant (Km) and vmax were 1.74 mol·L−1 and 0.42 mol CO2/(mg protein·min), respectively, at a low concentration of Pb2+, and 11.82 mol·L−1 and 0.28 mol CO2/(mg protein·min), respectively, at a high concentration of Pb2+. The spectroscopy assays suggested that the Pb2+ was determined to be directly bound to rubisco; the binding site of Pb2+ to rubisco was 1.1 and the binding constants were 8.63×104 and 2.18×105 L/mol. Based on the analysis of inductively coupled plasma‐mass spectrometry (ICP‐MS) and the circular dichroism (CD) spectra, it was concluded that Pb2+ replaced Mg2+ from the catalytic center in rubisco and the binding of Pb2+ entirely altered the primary conformation of rubisco, implying that the Pb2+ coordination created a new metal ion‐active site form of rubisco, thus leading to a reduction in the carboxylase activity of rubisco.
A Simple Design to Realize Micro‐column Separation by Conventional Analytical HPLC
Authors: GONG Wenjun , ZHANG Junxia , ZHANG Yuping , ZHANG Yijun , TIAN Mengkui , WU Dafu 
Published: May 2009

AbstractThe conventional analytical HPLC was successfully developed for micro‐column separation by using a simple eluate splitting system, self‐preparation of packing column and on‐capillary column detector in our laboratory. Porous inlet frit in fused silica capillary was rapidly prepared by sintering stainless steel powders under 500 meshes for about 20 s. The use of such frits or metal meshes in capillary to retain C18 particles of chromatographic packing was demonstrated to be stable and specially robust with continuous packing and long chromatographic runs. Furthermore, the chromatographic behavior was detailedly evaluated by changing the flow rate and the percentage of mobile phase using the prepared capillary column. Under the optimal experimental conditions, baseline separation of the model analytes including thiourea, benzene, toluene, ethylbenzene was obtained with a high column efficiency near 70000N (plates/m) by the developed capillary‐HPLC.
Removal of Chloroform from Hydrochloride Acid Solution Using Fine Powder of Polymer as Adsorbent
Authors: LU Yingzhou , QUE Yong , LI Chunxi , MENG Hong , WANG Zihao 
Published: May 2009

AbstractIn order to choose a suitable adsorbent for the removal of chloroform from its hydrochloric acid solution, the adsorptive ability of some polymer adsorbents was investigated in terms of their adsorption curves in water and 20% hydrochloric acid solutions at 298.15 K, and compared with that of active carbon (AC) and solid paraffin (SP). The adsorbents studied include the fine powders of chlorinated rubber (CR), polypropylene (PP), chlorinated polypropylene (CPP) and polyvinylchloride (PVC). The results showed that the adsorption behavior followed the Langmuir equation and the adsorption ability of these adsorbents followed the order AC>PVC>CR>PP>CPP>SP. This order is basically in line with the decrease of chloro‐content of the adsorbents from PVC to SP. The adsorptivity of PVC and CR was nearly equivalent to that of AC with their saturated adsorption being about 1.4 g‐CHCl3 (g‐absorbent)−1. For all adsorbents studied, the adsorption capacity always decreases with the increase of hydrochloric acid concentration. It is showed that the commercial polymer powder of PVC or CR can be used as an efficient absorbent for the removal of chloroform from its aqueous solution for its low cost, good adsorption ability and ease of thermal desorption for recycling.
Development and Validation of Selective Spectrophotometric Methods for the Determination of Pregabalin in Pharmaceutical Preparation
Authors: ARMAĞAN Önal 
Published: May 2009

AbstractThree simple, quick and sensitive methods are described for the spectrophotometric determination of pregabalin (Pgb) in pharmaceutical preparations. Among them, the first two methods are based on the reaction of Pgb as n‐electron donors with 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone (DDQ) and 7,7,8,8‐tetracyanoquinodimethane (TCNQ) as π‐acceptors to give highly colored complex species. The colored products were quantitated spectrophotometrically at 494 and 841 nm for DDQ and TCNQ, respectively. Optimization of the different experimental conditions was conducted. Beer's law was obeyed in the concentration ranges 2.0–30.0 and 1.5–10 g·mL−1 for DDQ and TCNQ methods, respectively. The third method is based on the interaction of ninhydrin (NN) with primary amine present in the pregabaline. This reaction produces a blue coloured product in N,N‐dimethylformamide (DMF) medium, which absorbs maximally at 573 nm. Beer's law was found in the concentration range 40.0–180.0 µg·mL−1. The methods were applied successfully to the determination of this drug in pharmaceutical dosage forms.
Synthesis of β‐Hydroxy Sulfides via Thiolysis of Epoxides Using S‐Alkylisothiouronium Salts as Thiol Equivalents in Basic Aqueous Medium
Authors: ZHU Jirang , LI Ridong , GE Zemei , CHENG Tieming , LI Runtao 
Published: May 2009

AbstractS‐Alkylisothiouronium salt as a nontoxic, odorless and simply operational alternative of thiol was reacted with different kinds of epoxides in basic aqueous medium at room temperature affording the β‐hydroxy sulfides with high regioselectivity in excellent yields.
Fragmentation Study of 2‐Amino‐4H‐1,3‐oxazines and Octahydro‐4‐phenyl‐2H‐pyrano[2,3‐d]pyrimidin‐2‐ones: Identification of Heterocyclic Six‐membered Ring in Three‐component Reactions
Authors: HU Nan , TAI Yuanpo , WAN Jieping , PAN Yuanjiang 
Published: May 2009

AbstractThe fragmentation behavior of ten 2‐amino‐4H‐1,3‐oxazines and seven octahydro‐4‐phenyl‐2H‐pyrano[2,3‐d]‐pyrimidin‐2‐ones was investigated by electrospray ionization tandem mass spectrometry (ESI‐MSn). When the precursor ions were protonated oxazines, two predominant fragmentation pathways were observed with elimination of CH2N2 and HCNO, respectively. The product ion [M+H−60]+ could be observed from both pathways. While in the type of pyrimidin‐2‐ones, only direct loss of 60 Da (urea) could be observed. The fragmentation pathways were investigated by high‐resolution mass spectrometry and deuterium‐labeling experiments, and the characteristic fragmentations presented here could be convenient for future identification of resembled derivatives, especially in high throughput screening combinatorial chemistry.
Design and Synthesis of Matrix Metalloprotease Photoaffinity Trimodular Probes
Authors: QIU Wenwei , XU Jie , LI Xin , ZHONG Li , LI Jingya , LI Jia , NAN Fajun 
Published: May 2009

AbstractTo explore the molecular mechanism of the matrix metalloproteinases (MMPs) in tumor processes, two photoaffinity trimodular probes were designed and synthesized based on the structure activity relationship and the following photoaffinity labelling experiments afforded positive results.
An Efficient Four‐Component, One‐Pot Synthesis of Poly‐Substituted Pyrimidines in Water
Authors: WANG Zhongqing , GE Zemei , CHENG Tieming , LI Runtao 
Published: May 2009

AbstractAn efficient environmentally friendly synthesis of poly‐substituted pyrimidines has been developed via a four‐component, one‐pot reaction of malononitrile, carbon disulfide, alkyl halide and S‐alkylisothiouronium salt in water at room temperature. Water as solvent, mild reaction conditions, short reaction time, simple experimental procedures, broad scope of substrates and good yields are the main advantages of this method.
Design and Synthesis of Trypanosoma brucei Active 1‐Alkyloxy and 1‐Benzyloxyadamantano 2‐Guanylhydrazones
Authors: Papanastasiou Ioannis , Tsotinis Andrew , Zoidis Grigoris , Kolocouris Nicolas , Prathalingam S. Radhika , Kelly John M. 
Published: May 2009

AbstractTreating African trypanosomiasis: The synthesis and biological evaluation of novel 1‐alkyloxy and 1‐benzyloxyadamantano 2‐guanylhydrazones, their 1‐dioxa congeners and two 1‐benzyladamantano 2‐guanylhydrazones is reported. Preliminary structure–activity relationship data were elucidated and lead compounds suitable for further optimization were discovered.magnified image
First‐Principles Quantum Calculations on the Infrared Spectrum and Vibrational Dynamics of the Guanine‐Cytosine Base Pair
Authors: Yagi Kiyoshi , Karasawa Hideyuki , Hirata So , Hirao Kimihiko 
Published: May 2009

AbstractVibrational resonance plays a vital role in manifesting a broad infrared band (>300 cm−1) and ultrafast vibrational energy relaxation (<100 femtoseconds) of the intermolecular NH stretching vibrations (see spectra).magnified image
Functional analysis of Pcipg2 from the straminopilous plant pathogen Phytophthora capsici
Authors: Sun Wen Xiu , Jia Yong Jian , Feng Bao Zhen , O'Neill Nichole R. , Zhu Xiao Ping , Xie Bing Yan , Zhang Xiu Guo 
Published: May 2009

AbstractPhytophthora capsici causes serious diseases in numerous crop plants. Polygalacturonases (PGs) are cell wall‐degrading enzymes that play an important role in pathogenesis in straminopilous pathogens. To understand PGs as they relate to the virulence of P. capsici, Pcipg2 was identified from a genomic library of a highly virulent P. capsici strain. Pcipg2 was strongly expressed during symptom development after the inoculation of pepper leaves with P. capsici. The wild protein (PCIPGII) was obtained from the expression of pcipg2 and found that increasing activity of PGs in PCIPGII‐treated pepper leaves was consistent with increasing symptom development. Asp residues in active sites within pcipg2 affected PCIPGII activity or its virulence on pepper leaves. Results show that pcipg2 is an important gene among pcipg genes, and illustrate the benefit of analyzing mechanisms of pathogenicity during the period of host/parasite interaction. genesis 47:535–544, 2009. © 2009 Wiley‐Liss, Inc.
Factor analysis of the Montgomery Aasberg depression rating scale in an elderly stroke population
Authors: Farner Lasse , Wagle Jørgen , Flekkøy Kjell , Wyller Torgeir Bruun , Fure Brynjar , Stensrød Brynhild , Engedal Knut 
Published: May 2009

AbstractBackgroundDepression is frequent in elderly stroke patients, and the pathophysiology may involve psychological as well as organic mechanisms.AimTo explore construct validity of the Montgomery Aasberg Depression Rating Scale using factor analysis and investigate whether symptom clusters of depression after stroke are associated with patient characteristics.MethodsA sample of 163 stroke patients was assessed by the Montgomery Aasberg Depression Rating Scale. Pre‐stroke assessment was accomplished by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE), the Barthel ADL Index and patient's medical history. Post‐stroke assessment was performed with the Mini Mental State Examination (MMSE), the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), the Star Cancellation Test, the Barthel ADL Index, the modified Rankin Scale (mRS) and the National Institute of Health Stroke Scale (NIHSS). Information was collected from the patients' records. A principal components factor analysis followed by oblique rotation was performed.ResultsAmong the patients, 56.4% scored between 7 and 19 on the Montgomery Aasberg Depression Rating Scale, and 13% had a score above 19. The factor analysis resulted in three factors, called anhedonia (lassitude, inability to feel, suicidal thoughts, loss of appetite), sadness (observed sadness, reported sadness, pessimism) and agitation (inner tension, lack of concentration, disturbed sleep). Anhedonia correlated with cognitive impairment, whereas sadness correlated with sensorimotor and cranial nerve deficits. Agitation had low internal reliability and did not correlate with any systematic patients characteristics.ConclusionWe found three distinct factors. The factor anhedonia is related to cognitive impairment, sadness to neurological impairment due to the stroke and agitation to somatic factors not directly related to the stroke. Copyright © 2009 John Wiley & Sons, Ltd.
Conditional deletion of ferritin H in mice induces loss of iron storage and liver damage #
Authors: Darshan Deepak , Vanoaica Liviu , Richman Larry , Beermann Friedrich , Kühn Lukas C. 
Published: May 2009

Abstract
Ferritin plays a central role in iron metabolism by acting both as iron storage and a detoxifying protein. We generated a ferritin H allele with loxP sites and studied the conditional ferritin H deletion in adult mice. Ten days after Mx-Cre induced deletion, ferritin H messenger RNA (mRNA) was below 5% in the liver, spleen, and bone marrow of deleted mice compared to control littermates. Mice lost their cellular iron stores indicating the requirement of ferritin H in iron deposition. Serum iron and transferrin saturation were slightly increased and correlated with a two-fold increased liver hepcidin 1 mRNA and a reduced duodenal DcytB mRNA level. Under a normal iron regimen, deleted mice survived for 2 years without visible disadvantage. Mice fed on a high iron diet prior to ferritin H deletion suffered from severe liver damage. Similarly, ferritin H deleted mouse embryonic fibroblasts showed rapid cell death after exposure to iron salt in the medium. This was reversed by wild-type ferritin H but not by a ferritin H mutant lacking ferroxidase activity. Cell death was preceded by an increase in cytoplasmic free iron, reactive oxygen species, and mitochondrial depolarization. Conclusion: Our results provide evidence that the iron storage function of ferritin plays a major role in preventing iron-mediated cell and tissue damage. (Hepatology 2009.)
Enhanced liver regeneration following changes induced by hepatocyte-specific genetic ablation of integrin-linked kinase #
Authors: Apte Udayan , Gkretsi Vasiliki , Bowen William C. , Mars Wendy M. , Luo Jian-Hua , Donthamsetty Shashikiran , Orr Ann , Monga Satdarshan P.S. , Wu Chuanyue , Michalopoulos George K. 
Published: May 2009

Abstract
Following liver regeneration after partial hepatectomy, liver grows back precisely to its original mass and does not exceed it. The mechanism regulating this “hepatostat” is not clear and no exceptions have been found to date. Although pathways initiating liver regeneration have been well studied, mechanisms involved in the termination of liver regeneration are unclear. Here, we report that integrin-linked kinase (ILK) (involved in transmission of the extracellular matrix [ECM] signaling by way of integrin receptors) and/or hepatic adaptations that ensue following ILK hepatocyte-targeted removal are critical for proper termination of liver regeneration. Following partial hepatectomy (PHx), mice with a liver-specific ILK ablation (ILK-KO-Liver) demonstrate a termination defect resulting in 58% larger liver than their original pre-PHx mass. This increase in post-PHx liver mass is due to sustained cell proliferation driven in part by increased signaling through hepatocyte growth factor (HGF), and the β-catenin pathway and Hippo kinase pathways. Conclusion: The data indicate that ECM-mediated signaling by way of ILK is essential in proper termination of liver regeneration. This is the first evidence of a defect leading to impaired termination of regeneration and excessive accumulation of liver weight following partial hepatectomy. (Hepatology 2009.)
Long-term reduction of jaundice in Gunn rats by nonviral liver-targeted delivery of Sleeping Beauty transposon #
Authors: Wang Xia , Sarkar Debi P. , Mani Prashant , Steer Clifford J. , Chen Yong , Guha Chandan , Chandrasekhar Voshavar , Chaudhuri Arabinda , Roy-Chowdhury Namita , Kren Betsy T. , Roy-Chowdhury Jayanta 
Published: May 2009

Abstract
Asialoglycoprotein receptor (ASGPR)-mediated endocytosis has been used to target genes to hepatocytes in vivo. However, the level and duration of transgene expression have been low because of lysosomal translocation and degradation of the DNA and lack of its integration into the host genome. In this study we packaged the DNA of interest in proteoliposomes containing the fusogenic galactose-terminated F-glycoprotein of the Sendai virus (FPL) for targeted delivery to hepatocytes. After the FPL binds to ASGPR on the hepatocyte surface, fusogenic activity of the F-protein delivers the DNA into the cytosol, bypassing the endosomal pathway. For transgene integration we designed plasmids containing one transcription unit expressing the Sleeping Beauty transposase (SB) and another expressing human uridinediphosphoglucuronate glucuronosyltransferase-1A1 (pSB-hUGT1A1). The latter was flanked by inverted/direct repeats that are substrates of SB. In cell culture, FPL-mediated delivery of the E. coli β-galactosidase gene (LacZ) resulted in transduction of ASGPR-positive cells (rat hepatocytes or Hepa1 cell line), but not of ASGPR-negative 293 cells. Intravenous injection of the FPL-entrapped pSB-hUGT1A1 (4-8 μg/day, 1-4 doses) into UGT1A1-deficient hyperbilirubinemic Gunn rats (model of Crigler-Najjar syndrome type 1) resulted in hUGT1A1 expression in 5%-10% of hepatocytes, but not in other cell types. Serum bilirubin levels declined by 30% ± 4% in 2 weeks and remained at that level throughout the 7-month study duration. With histidine containing FPL, serum bilirubin was reduced by 40% ± 5%, and bilirubin glucuronides were excreted into bile. No antibodies were detectable in the recipient rats against the F-protein or human UGT1A1. Conclusion: FPL is an efficient hepatocyte-targeted gene delivery platform in vivo that warrants further exploration toward clinical application. (Hepatology 2009.)
Potential impact of long-term nucleoside therapy on the mortality and morbidity of active chronic hepatitis B #
Authors: Toy Mehlika , Veldhuijzen Irene K. , de Man Robert A. , Richardus Jan Hendrik , Schalm Solko W. 
Published: May 2009

Abstract
The potential impact of long-term antiviral therapy on the burden of chronic hepatitis B has hardly been documented. The aim of this study was to estimate the effects of prolonged antiviral therapy and antiviral resistance on the mortality and morbidity of active chronic hepatitis B patients. A population cohort of chronic hepatitis B patients in the Netherlands was constructed and stratified according to 10-year age groups, prevalence of hepatitis B surface antigen, hepatitis B virus DNA level, alanine aminotransferase level, hepatitis B e antigen status, and presence of cirrhosis. A Markov model was created to mathematically simulate the cohort's progression through a finite series of health states. The analysis was performed on the basis of four scenarios: natural history, long-term therapy with a high-resistance profile drug without or with salvage, and therapy with a low-resistance profile drug. It has been estimated that there were 64,000 people (0.4%) suffering from chronic hepatitis B infection in the Netherlands in 2005, with 6521 (10%) of them having high viremia and elevated alanine aminotransferase levels. Within a 20-year period, 1725 (26%) of the 6521 patients in the active chronic hepatitis B cohort will die because of liver-related causes. Of the 5685 without cirrhosis at entry, 1671 (29%) will develop cirrhosis. Of those 836 with cirrhosis at entry, 619 (74%) will die within a 20-year period. If this active chronic hepatitis B cohort is fully detected and treated, mortality related to liver disease can be reduced by 80% if a low-resistance profile drug is chosen from the start. The effect is due to both the reduction in complications of cirrhosis and the prevention of the development of cirrhosis. Conclusion: Long-term antiviral therapy with a strategy that minimizes or controls resistance will have a major preventive effect on liver-related mortality and morbidity. (Hepatology 2009.)