bluuebunny/crossref_metadata_2025_split huggingface dataset:
Morphological alterations in oxidative muscles and mitochondrial structure associated with equine atypical myopathy
Authors: CASSART D. , BAISE E. , CHEREL Y. , DELGUSTE C. , ANTOINE N. , VOTION D. , AMORY H. , ROLLIN F. , LINDEN A. , COIGNOUL F. , DESMECHT D. 
Published: March 2007

Summary Reasons for performing study: There is a lack of well documented studies about muscular lesions in equine atypical myopathy (EAM). Objectives: To characterise morphopathological changes of striated muscles and myocardium, to progress understanding of this disease. Methods: Thirty‐two horses age 0.5–7 years kept on pasture were referred for a sudden ataxia/myoglobinuria syndrome. Clinical examination (stiffness, muscle pain, muscle fasciculations, abnormal gait, recumbency, myoglobinuria, tachycardia, sweating) and plasma CPK, LDH and AST levels were consistent with extensive myonecrosis and, together with anamnestic data, with so‐called ‘equine atypical myopathy’ (EAM), a disease of unknown aetiology reported since 1939. Macroscopic and microscopic (histology, histoenzymology, ultrastructure) lesions were evaluated. Results: Necropsic examination revealed large areas of muscle necrosis, the extent and severity of which varied between cases and muscles, but which were clearly more constant and severe in respiratory and postural muscles and in the myocardium. Histology highlighted a multifocal and monophasic process compatible with Zenker degeneration/necrosis that mostly and segmentally affected type 1 fibres. Histochemical evaluation revealed a weak and disorganised pattern of NADH tetrazolium reductase staining, the absence of calcium salts precipitates and a dramatic accumulation of lipid droplets. Ultrastructural examination often revealed fibres of which the sole modifications were altered mitochondria and sarcoplasmic lipidosis. Conclusions: Taken together, the data suggest that a primary alteration of mitochondria should be considered, although secondary mitochondrial abnormalities have yet to be ruled out. Potential relevance: The morphological features gathered here reveal that EAM shares most of the characteristics of toxic myopathies.
Endoscopic scoring of the tracheal septum in horses and its clinical relevance for the evaluation of lower airway health in horses
Authors: KOCH C. , STRAUB R. , RAMSEYER A. , WIDMER A. , ROBINSON N. E. , GERBER V. 
Published: March 2007

Summary Reasons for performing study: Although endoscopic scoring of the tracheal septum thickness is used as a diagnostic tool for evaluation of lower airway disease, its clinical relevance and reliability have never been critically assessed in the horse. Objectives: To investigate if septum thickness scores (STS) are reliable and serve as a clinically useful indicator of lower airway disease status and/or inflammation. Methods: The variance of STS attributable to the horse, observer and changes over time was determined. The distribution of STS in a population of clinically normal horses and correlations of STS with age, gender, as well as mucus accumulation and cell differentials of tracheobronchial secretions and bronchoalveolar lavage fluid were investigated. Effects of altered pulmonary ventilation, induced by different drugs, on STS were assessed. Finally, STS of horses affected with recurrent airway obstruction (RAO) were compared to those of clinically normal horses. Results: Recorded STS showed excellent intra‐ and satisfactory interobserver agreement. Established clinical, endoscopic and cytological measures of lower airway inflammation, i.e. mucus accumulation scores and airway neutrophilia, did not correlate with STS. In horses age ≥10 years, septum scores were significantly higher (P = 0.022) than in younger horses. Septum thickness scores did not differ significantly between clinically normal and RAO‐affected horses both in exacerbation and in remission. Horses with markedly increased breathing effort (i.e. with metacholine‐ or lobeline hydrochloride‐challenge), often differed markedly (up to 1.9 scores), but the average of end‐inspiratory and end‐expiratory STS did not differ from baseline STS. Conclusions and clinical relevance: Endoscopic STS are a reproducible measure, but STS did not correlate with clinical, endoscopic and cytological findings indicative of RAO or inflammatory airway disease.
Structure‐properties relationship in resol/montmorillonite nanocomposites
Authors: Manfredi L. B. , Puglia D. , Kenny J. M. , Vázquez A. 
Published: March 2007

AbstractPolymer/layered silicate nanocomposites were prepared, adding modified, and nonmodified montmorillonites to a resol resin. It was observed that the composites exhibited an intercalated disordered structure by means of X‐ray diffraction (XRD) and transmission electronic microscopy. The crosslinking density of the resol network was greatly influenced by the presence and type of clay that was added to the resin. The composites filled with the modified montmorillonites showed a lower glass transition temperature value as well as a higher degradation peak at ∼ 400°C, which is characteristic of the degradation of methylene bridges, indicating a decrease in the crosslinking density of the resol network when modified clays are added. Resol/unmodified montmorillonite composites exhibited different behavior comparing to the other composites and the resol. A higher thermal resistance was observed in the fragmentation zone and a different tan δ response was seen in the DMA analysis. These differences in the behavior of the composites could be because of the interaction between the resol prepolymer and the clay modifiers and as a result of their chemical compatibility. The hardness and elastic modulus of the resol were improved with the addition of clays. However, higher values were obtained for the composite made with the more dispersed montmorillonite. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Stoichiometric and nonstoichiometric polyelectrolyte complex of chitosan and polyethyleneglycol‐monosuccinate: Preparation and characterization
Authors: Son Taewon , Kim Daesun , Kim Byunggiu , Koo Kang , Park Youngmi , Kim Jungae , Lim Haksang 
Published: March 2007

AbstractStoichiometric and nonstoichiometric polyelectrolyte complex (PEC) was prepared with polyethylene glycol‐monosuccinate (PEGMS), and chitosan (CS). A series of PEGMS were synthesized by a 1 : 1 mol ratio between PEG and succinic anhydride. Then, the novel PEC was prepared by a various mole reaction of the above synthesized PEGMS and CS. The physicochemical properties of the synthesized PEC was characterized by using elemental analysis, FTIR, 1H, and 13C nuclear magnetic resonance, dissolution behavior, and phase transition phenomenon. Furthermore, some properties of the PEC obtained were analyzed by UV‐Visible spectrometry, wide‐angle X‐ray diffraction, differential scanning calorimeter, scanning electron microscope, and estimated solubility, and cell viability assay, respectively. It was found that the observed FTIR, 1H, and 13C‐NMR data was in good agreement with the chemical structure of the prepared PEGMS and PEC. The dissolution behaviors of nonstoichiometric PEC were found to depend on the pH of the solution as well as on the PEGMS/CS composition. The study of MTT assay suggested that the viability of HepG2 human hepatoblastoma cell on PEC were increased significantly in accordance with mole ratio of CS. As the results, the obtained several product is a useful intermediate, which permits further chemical modification for the amino group of CS and may have potential applications in biocompatible or cosmetic systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Poly(methyl methacrylate) toughened by ethylene‐vinyl acetate copolymer: Physico‐mechanical, thermal, and chemical properties
Authors: Poomalai P. , Ramaraj B. , Siddaramaiah  
Published: March 2007

AbstractBlends of poly(methyl methacrylate) (PMMA) with different composition viz., 5, 10, 15, and 20 wt % of ethylene‐vinyl acetate (EVA) copolymer were prepared by extrusion in a corotating twin screw extruder. These prepared PMMA/EVA blends have been characterized for physicomechanical properties such as density, surface hardness, izod impact strength, tensile strength, tensile elongation, and tensile modulus. The chemical aging and heat aging tests were performed on the blends by exposing them to different chemical environments and to 80°C for 168 h respectively. The influence of chemical aging and heat ageing on the mechanical performance of PMMA/EVA blends has been studied. The PMMA/EVA blends were also characterized for thermal properties such as vicat softening point (VSP) and melt flow index (MFI). That means significant improvement in impact strength of PMMA was noticed after incorporation of EVA into PMMA matrix and it lies in the range 19.1–31.96 J/m. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Influence of low‐temperature plasma on the ink‐jet‐printed cotton fabric
Authors: Yuen C. W. M. , Kan C. W. 
Published: March 2007

AbstractThis article studies the effect of low‐temperature plasma (LTP) on an ink‐jet‐printed cotton fabric. Owing to the specific printing and conductivity requirements for ink‐jet printing, none of the conventional printing chemicals used for cotton fabric can be directly incorporated into the ink formulation. As a result, the cotton fabric requires pretreatment with the printing chemicals prior to the stage of ink‐jet printing. The aim of this article is to study the possibility and effectiveness of applying LTP treatment to enhance the performance of pretreatment paste containing sodium alginate so as to improve the properties of the ink‐jet‐printed cotton fabric. Scanning electron microscopic pictures show that LTP treatment may cause cracks on the fiber surface and hence more dyes could approach the fiber surface during the ink‐jet printing process, leading to a higher dye uptake subsequently. In addition, not only the dye uptake is increased after the LTP treatment but the color‐fastness properties and the definition of the final print marks are also improved. Therefore, LTP pretreatment in couple with the ink‐jet printing technique could improve the final printed properties of cotton fabric. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Synthesis of calix[4]crown‐4 oligomers containing hard and soft ion binding sites
Authors: Li Haibing , Tian Demei , Xiong Dejun , Gao Zhinong 
Published: March 2007

AbstractThree calix [4]crown‐4 derivatives and their oligomers, p‐tert‐butylcalix [4]crown‐4 oligomer 5, p‐tert‐butylcalix [4]dioxacrown‐4 oligomer 6, p‐tert‐butylcalix [4]diazacrown‐4 oligomer 7 that contain hard and soft ion binding sites, are synthesized to estimate selective extraction of cesium ions from the aqueous to the organic phase. The binding sites may complex alkali metal ions or transition metal ions selectively. Oligomers are fairly good extractants for transition metal ions in comparison with their monomers, which suggests that polyoxyethylene bridges are efficient for complexing metal ions, especially for transition metal ions. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007
Early versus late surgical drainage for obstructive pancreatitis in an experimental model
Authors: Lamme B , Boermeester M A , Straatsburg I H , van Buijtenen J M , Boerma D , Offerhaus G J A , Gouma D J , van Gulik T M 
Published: March 2007

Abstract

Background
Chronic pancreatitis (CP) is characterized by intractable abdominal pain, and pancreatic exocrine and endocrine dysfunction. This study investigated whether early surgical drainage of pancreatic duct obstruction leads to improved recovery of pancreatic function compared with late surgical drainage in an experimental model of chronic obstructive pancreatitis.

Methods
Twenty-one piglets underwent pancreatic duct ligation and subsequent longitudinal pancreaticojejunostomy after 3 weeks (early drainage) or 6 weeks (late drainage), and drainage continued for 6 weeks. In controls with CP pancreatic duct ligation was continued for 12 weeks without a drainage procedure.

Results
Histological pancreatitis scores decreased with early drainage (P = 0·005), but not with late drainage. Pancreatic secretion of amylase and lipase was restored after early but not late drainage (P = 0·003 and P = 0·048 respectively). Excretion levels of lipase were restored to near-baseline preligation levels after early drainage. Pancreatic endocrine function (glucose tolerance test) showed no insufficiency in either group.

Conclusion
In this model of early versus late surgical drainage of obstructive pancreatitis, histology grades and pancreatic exocrine function showed improvement in the early drainage group but no recovery in the late drainage group.
Relaxation of the isolated human internal anal sphincter by sildenafil
Authors: Ballester C , Sarriá B , García-Granero E , Morcillo E J , Lledó S , Cortijo J 
Published: March 2007

Abstract

Background
Hypertonicity of the internal anal sphincter (IAS) appears to be involved in the pathogenesis of anal fissure. The relaxant effects of sildenafil, a selective phosphodiesterase 5 (PDE5) inhibitor, on isolated human IAS were investigated.

Methods
The efficacy (maximal effect, Emax) and potency (−log IC50, where IC50 is half-maximal inhibitory concentration) of the PDE5 inhibitors, sildenafil and zaprinast, and of nitric oxide donors, sodium nitroprusside and glyceryl trinitrate, as relaxants of histamine (0·1 mmol/l)-induced tone were examined in IAS strips under isometric contraction. The presence of PDE5 isoenzymes and changes in intracellular calcium and cyclic nucleotide levels in IAS muscle were tested by real-time reverse transcriptase–polymerase chain reaction, epifluorescence microscopy and enzyme immunoassay respectively.

Results
Sildenafil produced a concentration-related inhibition of the mean(s.e.m.) histamine-induced tone (Emax 83(2) per cent, − log IC50 7·04(0·05); n = 12). Zaprinast produced relaxation to similar degree, but with lower potency. Nitric oxide donors also relaxed IAS. Sildenafil (1 µmol/l) produced a 1·8-fold increase in guanosine 3′,5′-cyclic monophosphate content, with no change in adenosine 3′,5′-cyclic monophosphate levels. Sildenafil markedly depressed the peak intracellular calcium increase evoked by histamine. PDE5A1, PDE5A2 and PDE5A3 transcripts were expressed in IAS muscle.

Conclusion
Sildenafil relaxes the augmented tone of human IAS in vitro. These results support the potential use of this PDE5 inhibitor in the treatment of chronic anal fissure.
Interaction study of aspirin or clopidogrel on pharmacokinetics of donepezil hydrochloride in rats by HPLC‐fluorescence detection
Authors: Wada Mitsuhiro , Nishiwaki Junichiro , Yamane Tomoko , Ohwaki Yuichi , Aboul‐Enein Hassan Y. , Nakashima Kenichiro 
Published: March 2007

AbstractThe present study aims to investigate the possibility of interaction of aspirin (Asp) or clopidogrel (CG) on donepezil (DP) hydrochloride in rats by HPLC‐fluorescence detection. The separation of DP was achieved in ca. 13 min without interference of Asp and CG on the chromatogram. DP levels in rat plasma with a single administration of DP (5 mg/kg, i.p., group I) and those with a co‐administration of Asp (200 mg/kg, p.o., group II or 200 mg/kg, i.p., group III) or CG (5 mg/kg, p.o., group IV) were monitored. The DP concentrations determined in rat plasma ranged from 25.0 to 336.1 ng/mL. Pharmacokinetic parameters for these groups were calculated and compared with one another. No significant difference was observed on the comparison of group I with other groups except for the mean resident time of group IV (p = 0.012). These basic findings may help clinical inference when DP is co‐administered with Asp and CG to human. Copyright © 2007 John Wiley & Sons, Ltd.
Structural Analysis of the Capsular Polysaccharide from Campylobacter jejuni RM1221
Authors: Gilbert Michel , Mandrell Robert E. , Parker Craig T. , Li Jianjun , Vinogradov Evgeny 
Published: March 2007

AbstractThe complete genome of Campylobacter jejuni strain RM1221 (Penner serotype HS:53) was reported recently and contains a novel capsular polysaccharide (CPS) biosynthesis locus. Cell‐surface carbohydrates such as CPS are known to be important for bacterial survival and often contribute to pathogenesis. In this study, we describe the complete structure of the CPS of C. jejuni RM1221, which was determined by using NMR spectroscopy, MS, and chemical methods. The CPS contains 6‐deoxy‐D‐manno‐heptose and D‐threo‐pent‐2‐ulose (D‐xylulose), two monosaccharides that are rarely found in bacterial polysaccharides. The CPS has a regular structure of a linear main chain of trisaccharide repeating units, composed of two α‐ and one β‐6‐deoxy‐D‐manno‐heptopyranose residues, which are linked through a phosphodiester linkage. Branching residues of xylulose are incorporated nonstoichiometrically: each trisaccharide repeating unit of the main chain bears no, one, or two xylulose residues. The xylulose glycosidic linkages are extremely acid labile, and it is not clear how they can be preserved under the acidic conditions of the gastrointestinal tract, where Campylobacter resides during infection. We have also shown that the CPS biosynthesis genes of C. jejuni RM1221 are conserved in other C. jejuni strains of the Penner serotype HS:53, including serotype HS:53 reference strain RM3435.
Mechanisms of Oxidation of Guanine in DNA by Carbonate Radical Anion, a Decomposition Product of Nitrosoperoxycarbonate
Authors: Lee Young Ae , Yun Byeong Hwa , Kim Seog K. , Margolin Yelena , Dedon Peter C. , Geacintov Nicholas E. , Shafirovich Vladimir 
Published: March 2007

AbstractPeroxynitrite is produced during inflammation and combines rapidly with carbon dioxide to yield the unstable nitrosoperoxycarbonate, which decomposes (in part) to CO3.− and .NO2 radicals. The CO3.− radicals oxidize guanine bases in DNA through a one‐electron transfer reaction process that ultimately results in the formation of stable guanine oxidation products. Here we have explored these mechanisms, starting with a spectroscopic study of the kinetics of electron transfer from 20–22mer double‐stranded oligonucleotides to CO3.− radicals, together with the effects of base sequence on the formation of the end‐products in runs of one, two, or three contiguous guanines. The distributions of these alkali‐labile lesions were determined by gel electrophoresis methods. The cascade of events was initiated through the use of 308 nm XeCl excimer laser pulses to generate CO3.− radicals by an established method based on the photodissociation of persulfate to sulfate radicals and the oxidation of bicarbonate. Although the Saito model (Saito et al., J. Am. Chem. Soc. 1995, 117, 6406–6407) predicts relative ease of one‐electron oxidations in DNA, following the trend 5′‐⋅⋅⋅GGG⋅⋅⋅ > 5′‐⋅⋅⋅GG⋅⋅⋅ > 5′‐⋅⋅⋅G⋅⋅⋅, we found that the rate constants for CO3.−‐mediated oxidation of guanines in these sequence contexts (k5) showed only small variation within a narrow range [(1.5–3.0)×107 M−1 s−1]. In contrast, the distributions of the end‐products are dependent on the base sequence context and are higher at the 5′‐G in 5′‐⋅⋅⋅GG⋅⋅⋅ sequences and at the first two 5′‐guanines in the 5′‐⋅⋅⋅GGG⋅⋅⋅ sequences. These effects are attributed to a combination of initial hole distributions among the contiguous guanines and the subsequent differences in chemical reaction yields at each guanine. The lack of dependence of k5 on sequence context indicates that the one‐electron oxidation of guanine in DNA by CO3.− radicals occurs by an inner‐sphere mechanism.
Cyano‐bridged Ln3+‐Cr3+ Binuclear Complexes [Ln(L)x(H2O)yCr(CN)6]·mL·nH2O (Ln=La–Nd, x=5, y=2, m=1 or 2, n=2 or 2.5; Ln=Sm–Dy, Er, x=4, y=3, m=0, n=1.5 or 2.0; L=2‐pyrrolidinone): Structure, Magnetism and Spin Density Map
Authors: Sun Xian‐Ru , Chen Zhi‐Da , Wang Ming‐Wei , Wang Bing‐Wu , Yan Feng , Cheung Kung‐Kai 
Published: March 2007

AbstractIn order to shed light upon the nature and mechanism of 4f‐3d magnetic exchange interactions, a series of binuclear complexes of lanthanide(3+) and chromium(3+) with the general formula [Ln(L)5(H2O)2Cr(CN)6]·mL·nH2O (Ln=La (1), Ce (2), Pr (3), Nd (4); x=5, y=2, m=1 or 2, n=2 or 2.5; L=2‐pyrrolidinone) and [Ln(L)4(H2O)3Cr(CN)6] ·nH2O (Ln=Sm (5), Eu (6), Gd (7), Tb (8), Dy (9), Er (10); x=4, y=3, m=0, n=1.5 or 2.0; L2‐pyrrolidinone) were prepared and the X‐ray crystal structures of complexes 2, 6 and 7 were determined. All the compounds consist of a Ln‐CN‐Cr unit, in which Ln3+ in a square antiprism environment is bridged to an octahedral coordinated Cr3+ ion through a cyano group. The magnetic properties of the complexes 3 and 6–10 show an overall antiferromagnetic behavior. The fitting to the experimental magnetic susceptibilities of 7 give g=1.98, J=0.40 cm−1, zJ′=−0.21 cm−1 on the basis of a binuclear spin system (SGd=7/2, SCr=3/2), revealing an intra‐molecular Gd3+‐Cr3+ ferromagnetic interaction and an inter‐molecular antiferromagnetic interaction. For 7 the calculation of quantum chemical density functional theory (DFT), combined with the broken symmetry approach, showed that the calculated spin coupling constant was 20.3 cm−1, supporting the observation of weak ferromagnetic intra‐molecular interaction in 7. The spin density distributions of 7 in both the high spin ground state and the broken symmetry state were obtained, and the spin coupling mechanism between Gd3+ and Cr3+ was discussed.
Sulfur‐Selective Desulfurization of Dibenzothiophene and Diesel Oil by Newly Isolated RhodococcuserythropolisNCC‐1
Authors: Li Yu‐Guang , Ma Jie , Zhang Qian‐Qian , Wang Chang‐Shui , Chen Qian 
Published: March 2007

AbstractA dibenzothiophene (DBT)‐desulfurizing bacteria strain was isolated from oil‐contaminated soils and identified as Rhodococcus erythropolis NCC‐1. Strain NCC‐1 was found to convert DBT to hydroxybiphenyl (2‐HBP) via the 4S pathway and also be able to use organic sulfur compounds other than DBT as a sole sulfur source. The strain could desulfurize 4,6‐dimethyldibenzothiophene (4,6‐DMDBT), which is one of the most recalcitrant dibenzothiophene derivatives to hydrodesulfurization. When two type of oils, a model oil [n‐hexadecane (n‐C16) containing DBT] and a hydrodesulfurized diesel oil with various organic sulfur compounds, were treated with Rhodococcus erythropolis NCC‐1 cells, the total sulfur content significantly decreased, from 150 to 20 mg/L for n‐C16 and from 554 to 274 mg/L for diesel oil. The newly isolated strain NCC‐1 is considered to have good potential for application in the biodesulfurization of fossil fuels.
Elementary trouble‐shooting for poor signal‐to‐noise ratios of NMR spectrometers
Authors: D. Traficante Daniel 
Published: March 2007

AbstractWhen the signal‐to‐noise ratio of an NMR spectrometer falls below an acceptable point, one or more of the following items need to be measured or tested: resolution, probe transmitter and receiver coils, observe and decoupler radio‐frequency power amplifiers (transmitters), electronic devices connecting the probe to the receiver in the console, and the receiver section in the console. An elementary trouble‐shooting procedure and a flow‐chart are presented to aid in isolating the specific problem area. The procedure is based on the standard methods employed for trouble‐shooting in the fieldof electronics. The overall spectrometer system is first divided into sections, and then each one is checked for proper operation. The section that is not operating properly is then further divided into smaller ones, and each section checked again. The process is continued until the smallest repairable unit is identified.
Fundamental Concepts of NMR in Paramagnetic Systems. Part II: Relaxation Effects
Authors: Satterlee James D. 
Published: March 2007

AbstractParamagnetic effects on nuclear relaxation processes are described in the framework of the Solomon‐Bloembergen concepts. The factors contributing to nuclear relaxation, including the instantaneous electron‐nuclear dipolar and contact couplings and the Curie spin effect, are described using simplified cases. Spectral effects are illustrated, and the factors that allow various metal ions to function as either shift or relaxation agents are qualitatively described.