bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of [13C]‐isotopomers of indole and tryptophan for use in the analysis of indole‐3‐acetic acid biosynthesis
Authors: Ilić Nebojša , Cohen Jerry D. 
Published: July 2004

AbstractThe direct conversion of indole to indole‐3‐acetic acid without tryptophan as an intermediate has previously been shown to occur in vivo, as well as in vitro, with seedlings of plants. In order to facilitate the purification of the enzymes that carry out the enzymatic synthesis of indole‐3‐acetic acid from labeled indole, it was necessary to develop an assay that had both high sensitivity and analytical precision. To obtain the required analytical resolution and to allow definitive product identification, [13C6]indole was synthesized for use in GC‐MS assays of the enzymatic conversion. Plants have been shown to be able to synthesize indole‐3‐acetic acid either directly from indole as well as by degradation of tryptophan. Thus, in order to allow the biochemical discrimination between these processes, the synthesized [13C6]indole was used as a starting material for a novel enzymatic synthesis of [13C]isotopomers of L‐tryptophan labeled at specific positions. Together, these isotope labeled indolic compounds offer powerful new approaches to understanding and differentiating routes of indole‐3‐acetic acid biosynthesis in vitro and in vivo. Copyright © 2004 John Wiley & Sons, Ltd.
Structural Effect on Thermal Cure and Property of Naphthalene‐Based Epoxies: Preparation and Characterization
Authors: Xu Kai , Chen Mingcai , Zhang Xiuju , Zhang Kui 
Published: July 2004

AbstractSummary: Three naphthalene‐based epoxy monomers containing different size of linkages between two naphthalene rings: CC covalent bond (1), methylene (2), cycloaliphatic hydrocarbon derived from limonene (3) were prepared, and the effect of molecular structure on thermal cure behavior and property analyzed. Judged from the combination of the dynamic DSC and isothermal FTIR results, the cure reactivities were found to increase in the order of 1 > 2 > 3 when dicyandiamide was used in the curing systems, and the situation was slightly different in the monomer/4,4′‐methylenedianiline systems. The differences in reactivity as well as in thermal and mechanical properties for the epoxies can be attributed to the differences of configuration and conformational changes during the formation of crosslinked networks. These thermosets exhibited high glass transition temperature (Tg) and had excellent thermal oxidative resistance.DSC thermograms for epoxy/dicyandiamide systems at a heating rate of 10 °C · min−1.magnified imageDSC thermograms for epoxy/dicyandiamide systems at a heating rate of 10 °C · min−1.
Role of cyclooxygenase‐1 and ‐2 in satellite cell proliferation, differentiation, and fusion
Authors: Mendias Christopher L. , Tatsumi Ryuichi , Allen Ronald E. 
Published: July 2004

AbstractSkeletal muscle satellite cells play an important role in muscle regeneration. Previous work has suggested that nonsteroidal anti‐inflammatory drugs may inhibit their activity. We cultured skeletal muscle satellite cells from 9‐month‐old Sprague‐Dawley rats and exposed them to naproxen sodium (a nonselective cyclooxygenase inhibitor), NS‐398 (a selective cyclooxygenase‐2 inhibitor), and SC‐560 (a selective cyclooxygenase‐1 inhibitor) for 96 h. Cyclooxygenase‐2 inhibition alone resulted in decreased satellite cell proliferation, and inhibition of both cyclooxygenase‐1 and cyclooxygenase‐2 resulted in decreased satellite cell differentiation and fusion. This study suggests that the cyclooxygenase enzymes appear to play an important part in satellite cell proliferation, differentiation, and fusion and that nonsteroidal anti‐inflammatory medication may have an adverse effect on muscle regeneration following injury. The use of a selective cyclooxygenase‐2 inhibitor over nonspecific cyclooxygenase inhibitors in the treatment of muscle injuries is not supported. Muscle Nerve 30: 497–500, 2004
Active hepatocyte growth factor is present in skeletal muscle extracellular matrix
Authors: Tatsumi Ryuichi , Allen Ronald E. 
Published: July 2004

AbstractWhen skeletal muscle is stretched or injured, satellite cells are activated to proliferate, and this process can be mediated by release of the active form of hepatocyte growth factor (HGF) from the extracellular matrix. The objective of these experiments was to determine whether the mechanism of release includes proteolytic activation of pro‐HGF. Extracellular HGF in uninjured adult rat extensor digitorum longus muscle was extracted by treatment with 1 M NaCl or heparinases I and III in the presence of a cocktail of serine protease inhibitors. Active HGF heterodimer was the predominant form present, but both pro‐HGF and active HGF were extracted when muscle was incubated with Triton X‐100 or crush‐injured. Incubation of exogenous pro‐HGF with uninjured or crush‐injured skeletal muscle resulted in cleavage to the active form, indicating that endogenous extracellular proteases are present and capable of rapidly converting pro‐HGF to active HGF. Finally, treatment with sodium nitroprusside, a nitric oxide (NO) donor, resulted in liberation of active HGF. These experiments indicate that the active form of HGF is present in the extracellular compartment of uninjured skeletal muscle; therefore, the mechanism of HGF release in response to stretch and NO does not require proteolytic activation of pro‐HGF. Muscle Nerve, 2004
Cytoplasmic body myopathy masquerading as motor neuron disease
Authors: Krishnan Arun V. , Pamphlett Roger , Burke David , Wills Edward J. , Kiernan Matthew C. 
Published: July 2004

AbstractCytoplasmic body myopathy (CBM) is characterized by proteinaceous inclusion bodies in muscle tissue. A 43‐year‐old woman presented with rapidly progressive weakness and dysphagia. Electromyography (EMG) elsewhere demonstrated lower‐limb chronic partial denervation. Muscle biopsy showed fiber size variation without diagnostic features. A diagnosis of possible motor neuron disease was made and the patient was commenced on riluzole. Subsequently, the patient's condition stabilized, prompting reassessment. Repeat EMG demonstrated no features of denervation and was more suggestive of a myopathic process. Review of the original muscle biopsy showed cytoplasmic bodies. The case highlights a further diagnostic possibility in the assessment of patients with “possible” motor neuron disease. The clinical features of CBM are briefly reviewed. Muscle Nerve, 2004
Methanol permeability and proton conductivity of polybenzimidazole and sulfonated polybenzimidazole
Authors: Pu Hongting , Liu Qizhi 
Published: July 2004

AbstractThe preparation of sulfonated polybenzimidazole (sPBI) by the grafting of (4‐bromomethyl) benzenesulfonate onto polybenzimidazole (PBI) has been investigated. The methanol permeability and proton conductivity of PBI and sPBI have been studied, and the effects of methanol concentration and temperature on the methanol permeability of PBI and sPBI membranes are discussed. The results showed that the PBI membrane is a good methanol barrier. Methanol permeability in this membrane decreases with increasing methanol concentration and increases with increasing temperature. The temperature‐dependence of methanol permeability of PBI and sPBI membranes is of the ‘Arrhenius type’. Methanol permeation of sPBI is less sensitive to temperature than that of PBI. However, sPBI is a poorer methanol barrier when compared to PBI. Methanol permeability in sPBI membranes increases with increasing methanol concentration and temperature. The proton conductivity of sPBI is 4.69 × 10−4 S cm−1 at room temperature in the hydrated state. The DC conductivity of sPBI–H3PO4 increases with increasing temperature. Proton transport in sPBI–H3PO4 is less sensitive to temperature than that in PBI–H3PO4. Copyright © 2004 Society of Chemical Industry
Child level correlates of teacher–student relationships: An examination of demographic characteristics, academic orientations, and behavioral orientations
Authors: Murray Christopher , Murray Kelly M. 
Published: July 2004

AbstractThe purpose of this investigation was to examine associations between different child characteristics and conflict, closeness, and dependency within teacher–student relationships. The participants were primarily students of color from lower socioeconomic status backgrounds in a large urban school district. The strength of associations between student demographic variables, academic orientations, behavioral orientations, and aspects of teacher–student relationships was examined. Findings indicated that these variables accounted for a significant amount of variance in teacher ratings of conflict and dependency in teacher–student relationships. Externalizing and internalizing symptomology demonstrated the strongest associations with the conflict and dependency relationship constructs. Preliminary implications of these findings for teachers and school psychologists are explored. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 751–762, 2004.
The role of school psychology in preventing depression
Authors: Herman Keith C. , Merrell Kenneth W. , Reinke Wendy M. , Tucker Carolyn M. 
Published: July 2004

AbstractTo advance the role of school psychologists in mental health prevention and wellness activities, in this article we describe (a) a social ecological theory for guiding school‐based prevention research, (b) the role of schools in the development and prevention of depression, (c) a continuum of school‐based support for meeting the needs of children who are currently depressed for preventing future internalizing distress for all children, and (d) social and political factors that must be considered if lasting change is to occur. We conclude with specific considerations for school psychologists. © 2004 Wiley Periodicals, Inc. Psychol Schs 41: 763–775, 2004.
Resorcinarene‐based ATRP initiators for star polymers
Authors: Strandman Satu , Luostarinen Minna , Niemelä Satu , Rissanen Kari , Tenhu Heikki 
Published: July 2004

AbstractTwo novel multifunctional initiators for atom transfer radical polymerization (ATRP) were synthesized by derivatization of tetraethylresorcinarene. The derivatization induced a change in the conformation of the resorcinarene ring, which was confirmed by NMR spectroscopy. The initiators were used in ATRP of tert‐butyl acrylate and methyl methacrylate, producing star polymers with controlled molar masses and low polydispersities. Instead of the expected star polymers with eight arms, polymers with four arms were obtained. Conformational studies on the initiators by rotating‐frame nuclear Overhauser and exchange spectroscopy NMR and molecular modeling suggested that of eight initiator functional groups on tetraethylresorcinarene, four are too close to each other to be able to initiate the chain growth. Starlike poly(tert‐butyl acrylate) macroinitiators were used further in the block copolymerization of methyl methacrylate. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4189–4201, 2004
Novel miktofunctional initiator for the preparation of an ABC‐type miktoarm star polymer via a combination of controlled polymerization techniques
Authors: Tunca U. , Ozyurek Z. , Erdogan T. , Hizal G. 
Published: July 2004

AbstractAn ABC‐type miktoarm star polymer was prepared with a core‐out method via a combination of ring‐opening polymerization (ROP), stable free‐radical polymerization (SFRP), and atom transfer radical polymerization (ATRP). First, ROP of ϵ‐caprolactone was carried out with a miktofunctional initiator, 2‐(2‐bromo‐2‐methyl‐propionyloxymethyl)‐3‐hydroxy‐2‐methyl‐propionic acid 2‐phenyl‐2‐(2,2,6,6‐tetramethyl‐piperidin‐1‐yl oxy)‐ethyl ester, at 110 °C. Second, previously obtained poly(ϵ‐caprolactone) (PCL) was used as a macroinitiator for SFRP of styrene at 125 °C. As a third step, this PCL–polystyrene (PSt) precursor with a bromine functionality in the core was used as a macroinitiator for ATRP of tert‐butyl acrylate in the presence of Cu(I)Br and pentamethyldiethylenetriamine at 100 °C. This produced an ABC‐type miktoarm star polymer [PCL–PSt–poly(tert‐butyl acrylate)] with a controlled molecular weight and a moderate polydispersity (weight‐average molecular weight/number‐average molecular weight < 1.37). The obtained polymers were characterized with gel permeation chromatography and 1H NMR. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4228–4236, 2004
Graft polymerization of polysilsesquioxane containing chloromethylphenyl groups by atom transfer radical polymerization
Authors: Sugizaki Toshio , Kashio Mikihiro , Kimura Atsuko , Yamamoto Shin‐ichi , Moriya Osamu 
Published: July 2004

AbstractPolysilsesquioxane with phenyl and chloromethylphenyl groups (PCPSQ) was prepared readily from phenyltrimethoxysilane and [2‐(chloromethylphenyl)ethyl]trimethoxysilane under acidic conditions. Polymerization with chloromethylphenyl groups on PCPSQ with methyl methacrylate (MMA) was conducted in the presence of a catalytic amount of copper(I) bromide and (−)‐sparteine. Atom transfer radical polymerization yielded a graft polymer (PCPSQ‐g‐MMA) efficiently, and no gelation was observed. The process was also applied to the preparation of graft block copolymers on PCPSQ with several methacrylate monomers. An advantage of the graft hybrid polymers was shown in improved thermal behavior. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4212–4221, 2004
Fast accurate evaluation of protein solvent exposure
Authors: Zhang Naigong , Zeng Chen , Wingreen Ned S. 
Published: July 2004

AbstractProtein solvation energies are often taken to be proportional to solvent‐accessible surface areas. Computation of these areas is numerically demanding and may become a bottleneck for folding and design applications. Fast graph‐based methods, such as dead‐end elimination (DEE), become possible if all energies, including solvation energies, are expressed as single‐residue and pair‐residue terms. To this end, Street and Mayo originated a pair‐residue approximation for solvent‐accessible surface areas (Street AG, Mayo SL. Pairwise calculation of protein solvent accessible surface areas. Fold Des 1998;3:253–258). The dominant source of error in this method is the overlapping burial of side‐chain surfaces in the protein core. Here we report a new pair‐residue approximation, which greatly reduces this overlap error by the use of optimized generic side‐chains. We have tested the generic‐side‐chain method for the ten proteins studied by Street and Mayo and for 377 single‐domain proteins from the CATH database (Orengo CA, Michie AD, Jones S, Jones DT, Swindells MB, Thornton JM. CATH‐A hierarchic classification of protein domain structures. Structure 1997;5:1093–1108). With little additional cost in computation, the new method consistently reduces error for total areas and residue‐by‐residue areas by more than a factor of two. For example, the residue‐by‐residue error (for buried area) is reduced from 7.42 Å2 to 3.70 Å2. This difference translates into a solvation energy difference of ∼0.2 kcal/mol per residue, amounting to a reduction in root‐mean‐square energy error of 2 kcal/mol for a 100 residue chain, a potentially critical difference for both protein folding and design applications. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Massive Upper Gastrointestinal Bleeding after Acid‐corrosive Injury
Authors: Tseng Yau‐Lin , Wu Ming‐Ho , Lin Mu‐Yen , Lai Wu‐Wei 
Published: July 2004

AbstractOur purpose was to delineate the characteristics and outcome of massive upper gastrointestinal bleeding (UGI) caused by acid‐corrosive injury and to determine its management protocol. From June 1988 to June 2000, all patients with the history of acid‐corrosive injury at our institution were reviewed. Patients with massive UGI bleeding (hematocrit level < 25% or transfusion of three or more units of whole blood required to restore normal vital sign) were enrolled into this study. Altogether, 12 (3.2%) of 378 patients with acid‐corrosive injury developed massive bleeding: 8 gastric bleeding, 2 duodenal bleeding, and 2 first gastric and then duodenal bleeding. Gastric bleedings started an average of 12.1 days after the initial injury (range 9–21 days). Duodenal bleeding usually occurred later, at 10.1 days (range 6–18 days) after a gastric or esophagogastric operation. Nine of the ten patients with gastric bleeding underwent surgery during the subacute stage: three esophagogastrectomy, three gastric mucosectomy with gastrostomy and jejunostomy, and three total or subtotal gastrectomy. Operative findings were hemorrhagic gastritis with diffuse mucosal bleeding. Two of four patients with duodenal bleeding underwent duodenotomy with suture‐ligation of bleeding vessels, and the other two had conservative treatment. Nine patients (75%) had postoperative complications. One patient (8%) died from complications of surgery performed to stop duodenal bleeding. Massive UGI bleeding rarely occurs after acid‐corrosive injury; but when it does, it occurs during the subacute stage. Aggressive surgical treatment is mandatory for gastric bleeding. How duodenal bleeding can be better managed requires further study.
Antiarrhythmic Effect of Ischemic Preconditioning in Recent Unstable Angina Patients Undergoing Coronary Artery Bypass Grafting
Authors: Wu Zhong‐Kai , Iivainen Tiina , Pehkonen Erkki , Laurikka Jari , Tarkka Matti R. 
Published: July 2004

AbstractCoronary artery bypass grafting (CABG) for unstable angina pectoris patients results in a higher incidence of arrhythmia and higher arrhythmic cardiac mortality. Ischemic preconditioning (IP) has proved effective in suppressing ischemia reperfusion arrhythmias in animals and in humans. The purpose of the present study was to investigate whether IP protects against postoperative arrhythmias in recent unstable angina patients undergoing urgent CABG. Forty‐one patients with recent unstable angina and three‐vessel coronary artery disease admitted for CABG were randomized into an IP group and a control group. The IP protocol involved twice occluding the ascending aorta with a cross‐clamp for 2 minutes, followed by 3 minutes of reperfusion. Twenty‐four‐hour continuous electrocardiography (24‐h ECG) was recorded from the preoperative day to the 2nd postoperative day. The incidences of supraventricular extrasystole (SVES), ventricular extrasystole (VES), supraventricular tachycardia (SVT), and ventricular tachycardia (VT) were 95.2%, 85.7%, 26.2%, and 26.2%, respectively, before surgery and 100.0%, 100.0%, 88.1%, and 76.2%, respectively, after surgery. IP significantly reduced the incidence of VT and the severity of SVES, VES, SVT, and VT after surgery. The period of mechanical ventilation and the length of stay in the intensive care unit were significantly shorter in the IP group. In summary, rhythm disturbances are common in CABG patients with recent unstable angina. IP significantly reduces rhythm disturbances, including SVES, VES, SVT, and VT after CABG. The findings indicate that IP could constitute an additional myocardial protective strategy in recently unstable angina patients undergoing CABG.
Enduring Effects of Thoracoscopic Heller Myotomy for Treating Achalasia
Authors: Lee Jang‐Ming , Wang Chih‐Hsien , Huang Pei‐Ming , Hsu Hsao‐Hsun , Chen Jin‐Shing , Lee Chun‐Jean , Lee Yung‐Chie 
Published: July 2004

AbstractMinimal invasive surgery using a laparoscopic or thoracoscopic approach for cardiomyotomy (Heller myotomy) has become a widely accepted procedure to treat achalasia of the esophagus. In this study, we evaluated the long‐term results of Heller myotomy achieved by performing video‐assisted thoracic surgery (VATS). We recruited patients with achalasia who had undergone VATS for Heller myotomy from 1991 to 2000 at the National Taiwan University Hospital. The myotomy was performed 6 cm above and 1 cm below the gastroesophageal junction. No fundoplication was performed during the procedure. The symptom score, which included dysphagia, regurgitation, and chest pain, was evaluated before and after surgery. Body weight was also recorded before and after surgery. The cases of 14 patients (4 men, 10 women) were studied. The mean patient age was 41.8 ± 4.9 years. No postoperative mortality or morbidity was found in these patients. The follow‐up duration was 56 ± 7.17 months. The dysphasia score improved from 3.0 preoperatively to 0.79 ± 0.30 postoperatively (p = 0.001). The reflux score improved from 2.64 ± 0.17 preoperatively to 0.50 ± 0.20 postoperatively (p = 0.001). All the improvements were still in place at the time of the most recent follow‐up examinations. Heller myotomy to treat achalasia using a thoracoscopic approach can provide satisfactory long‐term results.
Ocular Manifestations and Complications of Pyogenic Liver Abscess
Authors: Tan Yu‐Meng , Chee Soon‐Phaik , Soo Khee‐Chee , Chow Pierce 
Published: July 2004

AbstractIn anecdotal reports, septic metastatic lesions from a pyogenic liver abscess can result in endogenous endophthalmitis, an infection of intraocular contents. Recent reports suggest that this devastating complication is increasing in frequency. The initial presentation may be nonspecific and easily misdiagnosed by the surgical team. When the infecting organism is virulent, it tends to be rapidly progressive and often leads to permanent visual deterioration or blindness despite medical intervention. We conducted a study to determine the incidence of endophthalmitis associated with pyogenic liver abscess, to identify its associations, and to determine the outcome of treatment. A retrospective review of 289 patients with a clinical diagnosis of pyogenic liver abscess admitted between January 1995 and March 2001 revealed 10 patients (3.5%) with the complication of endogenous endophthalmitis. Among them, seven had a previous history of diabetes mellitus. The offending organism was Klebsiella pneumoniae in all cases. There was no mortality in this series. Final visual outcomes of our patients were as follows: Five had no light perception (two had undergone evisceration), one had light perception only, and four were able to visualize hand motion only. There is a trend toward a worse outcome when ocular symptoms are not diagnosed and treated within 24 hours of onset. Of the five patients who lost their eyesight completely, three were initially misdiagnosed, and referral to the ophthalmologist was delayed. Surgeons must be alert to the complication of endogenous endophthalmitis. Ocular symptoms in patients treated for pyogenic liver abscess must be referred early for an ophthalmologic consult. Increased awareness and a high index of suspicion are required for salvage of visual function.