bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative proteomics based on stable isotope labeling and affinity selection
Authors: Regnier Fred E. , Riggs Larry , Zhang Roujian , Xiong Li , Liu Peiran , Chakraborty Asish , Seeley Erin , Sioma Cathy , Thompson Robert A. 
Published: March 2003

AbstractDisease, external stimuli (such as drugs and toxins), and mutations cause changes in the rate of protein synthesis, post‐translational modification, inter‐compartmental transport, and degradation of proteins in living systems. Recognizing and identifying the small number of proteins involved is complicated by the complexity of biological extracts and the fact that post‐translational alterations of proteins can occur at many sites in multiple ways. It is shown here that a variety of new tools and methods based on internal standard technology are now being developed to code globally all peptides in control and experimental samples for quantification. The great advantage of these stable isotope‐labeling strategies is that mass spectrometers can rapidly target those proteins that have changed in concentration for further analysis. When coupled to stable isotope quantification, targeting can be further focused through chromatographic selection of peptide classes on the basis of specific structural features. Targeting structural features is particularly useful when they are unique to types of regulation or disease. Differential displays of targeted peptides show that stimulus‐specific markers are relatively easy to identify and will probably be diagnostically valuable tools. Copyright © 2002 John Wiley & Sons, Ltd.
Tandem mass spectrometry of Cu(II) complexes: the effects of ligand donor group on dissociation
Authors: Chaparro Amanda L. , Vachet Richard W. 
Published: March 2003

AbstractA quadrupole ion trap mass spectrometer was used to study the dissociation patterns of Cu(II) complexes with various linear podand ligands. Cu(II) complexes having different combinations of nitrogen‐, oxygen‐ and sulfur‐containing terminal functionality attached to a diethylenetriamine (DIEN) framework were ionized by electrospray and collision‐induced dissociation (CID) was used to generate product ions. Regardless of the particular functional groups present, the complexes undergo predominantly heterolytic cleavages of carbon–carbon bonds along the DIEN backbone with Cu remaining coordinated to one of the two terminal functional groups. Upon dissociation, Cu's preference to remain coordinated to a particular functional group follows the trend thioether > amine > imidazole > pyridine > ether. A simple evaluation of this trend based upon metal‐functional group binding affinity appears not to be adequate for fully explaining these observations. The tendency of Cu(II) to be reduced upon dissociation helps explain the observed trend, as does the flexibility of the functional group, which affects its ability to orient its dipole effectively toward the metal. Copyright © 2003 John Wiley & Sons, Ltd.
Charge state dependent collision‐induced dissociation of native and reduced porcine elastase
Authors: Hogan Jason M. , McLuckey Scott A. 
Published: March 2003

AbstractThe [M + 20H]20+–[M + 12H]12+ charge states of native and reduced porcine elastase, a 25.9 kDa serine protease, were subjected to collisional activation in a quadrupole ion trap. For most charge states, ion parking was used to increase the number of parent ions over that yielded directly by electrospray. Ion–ion proton transfer reactions were used to reduce product ion charge states largely to +1 to simplify spectral interpretation. Both forms of the protein show charge state dependent fragmentation behavior. The native protein, which contains four disulfide linkages, shows almost no evidence for fragmentation within the regions of the protein linked by disulfide bonds. However, at the lowest charge states studied, evidence for cleavage of a least one of the disulfide bonds was evident in the appearance of a c‐type ion. The highest charge states of native elastase showed several prominent cleavages C‐terminal to valine residues. As the charge state decreased, however, preferential cleavages at acidic amino acid residues became important. The reduced form of the protein did not show particularly prominent cleavages at valine residues. However, many of the same preferential cleavages at acidic amino acid residues noted for the native protein were also observed in the same charge states of the reduced protein. The reduced protein also showed additional cleavages from regions of the protein that are ordinarily protected by disulfide linkages in the native form. Copyright © 2003 John Wiley & Sons, Ltd.
Interactions among nitric oxide and Bcl‐family proteins after MPP+ exposure of SH‐SY5Y neural cells I: MPP+ increases mitochondrial NO and Bax protein
Authors: Dennis Jameel , Bennett James P. 
Published: March 2003

AbstractWe studied effects of methylpyridinium ion (MPP+) on apoptosis, cell death and regulation of Bcl‐2‐family proteins in SH‐SY5Y neuroblastoma cells. MPP+ increased intracellular accumulation of DNA‐histone complexes as a measure of apoptosis and decreased intracellular calcein fluorescence as a measure of cell death. If ATP synthesis was supported, MPP+ caused apoptosis in ρ0 cells devoid of electron transport function. Caspase inhibition blocked apoptosis but not cell death caused by MPP+. MPP+ increased levels of Bax, Bcl‐2 and Bcl‐XL proteins ∼2‐fold over 24 hr, with Bax increases occurring first; Bax did not increase in ρ0 cells. The Bax increase, but not that of Bcl‐2 or Bcl‐XL, was dependent on nitric oxide (NO) and seemed post‐transcriptional. DAF‐FM imaging revealed increased mitochondrial NO within hours of exposure to MPP+. Western blots showed a constitutive ∼130 kD protein that stained for NOS‐2, consistent with reports of mitochondrial nitric oxide synthase (mtNOS). MPP+ caused a NO‐dependent release of cytochrome C into cytoplasm. MPP+ increases mitochondrial NO levels and causes a NO‐dependent increase in Bax protein, providing a mechanism for NOS‐and Bax‐dependency of MPTP neurotoxicity in vivo and implicating locally produced NO as a signaling molecule used by mitochondria to manipulate cell death cascades. © 2003 Wiley‐Liss, Inc.
Nanoscopic aspects of radiobiological damage: Fragmentation induced by secondary low‐energy electrons
Authors: Sanche Léon 
Published: March 2003

Abstract

I.
Introduction
349

II.
Experimental Methods
352

A. Thin‐Film Preparation
352

B. Electron‐Stimulated Desorption (ESD) of Ions and Neutral Species
353

C. Analysis by Electrophoresis
354

III.
Interpretation of the Dependence of Ion and Neutral Yields on Incident Electron Energy
354

IV.
Results and Discussion
356

A. Desorption of Ions and Neutral Species from Water‐Ice Films Induced by Low‐Energy Electrons (LEEs)
356

B. Anion ESD from Thin Films of Deoxyribose Analogs
358

C. Anion ESD from Thin Films of DNA Bases
359

D. Neutral‐Species Desorption from Short Single‐DNA Strands Induced by LEEs
360

E. Sequence‐Specific Damage Induced by LEE Impact on Oligonucleotides
362

F. Anion ESD from the Peptide and Disulfide Bridges of Proteins
364

G. LEE Damage to Plasmid DNA
365

V.
Summary and Conclusions
366

Acknowledgments
367

References
367

Low‐energy electrons (LEEs) are produced in large quantities in any type of material irradiated by high‐energy particles. In biological media, these electrons can fragment molecules and lead to the formation of highly reactive radicals and ions. The results of recent experiments performed on biomolecular films bombarded with LEEs under ultra‐high vacuum conditions are reviewed in the present article. The major type of experiments, which measure fragments produced in such films as a function of incident electron energy (0.1–45 eV), are briefly described. Examples of the results obtained from DNA films are summarized along with those obtained from the fragmentation of elementary components of the DNA molecule (i.e., thin solid films of H2O, DNA bases, sugar analogs, and oligonucleotides) and proteins. By comparing the results of these different experiments, it is possible to determine fundamental mechanisms that are involved in the dissociation of biomolecules and the production of single‐ and double‐strand breaks in DNA, and to show that base damage is dependent on the nature of the bases and on their sequence context. Below 15 eV, electron resonances (i.e., the formation of transient anions) play a dominant role in the fragmentation of all biomolecules investigated. These transient anions fragment molecules by decaying into dissociative electronically excited states or by dissociating into a stable anion and a neutral radical. These fragments usually initiate other reactions with nearby molecules, causing further chemical damage. The damage caused by transient anions is dependent on the molecular environment. © 2003 Wiley Periodicals, Inc., Mass Spec Rev 21:349–369, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mas.10034
Local a posteriori error estimates and adaptive control of pollution effects
Authors: Liao Xiaohai , Nochetto Ricardo H. 
Published: March 2003

AbstractLocal a posteriori error estimators are derived for linear elliptic problems over general polygonal domains in 2d. The estimators lead to a sharp upper bound for the energy error in a local region of interest. This upper bound consists of H1‐type local error indicators in a slightly larger subdomain, plus weighted L2‐type local error indicators outside this subdomain, which account for the pollution effects. This constitutes the basis of a local adaptive refinement procedure. Numerical experiments show a superior performance than the standard global procedure as well as the generation of locally quasi‐optimal meshes. © 2003 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 19: 421–442, 2003
Diffusion in glassy polymers
Authors: Vrentas J. S. , Vrentas C. M. 
Published: March 2003

AbstractTwo versions of the free‐volume theory of diffusion are compared by considering differences in the predictions for the activation energy for the diffusion process. A number of data‐theory comparisons for free‐volume theory are discussed and evaluated. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 785–788, 2003
Effects of anti‐ecdysteroid quaternary derivatives of azole analogues of metyrapone on the post‐embryonic development of the red cotton bug (Dysdercus cingulatus F)
Authors: Bélai Iván , Fekete Gábor 
Published: March 2003

AbstractIn order to improve the larvicidal activity of the azole analogues of metyrapone, previously found to have a strong inhibitory activity on ecdysone 20‐monooxygenase (E‐20‐M) from the fleshfly Neobellieria bullata Parker, soft‐alkylated compounds (3‐(1,1‐dimethyl‐2‐oxo‐2‐phenylethyl)‐1‐dodecanoyloxymethyl‐1H‐imidazolium chloride, sPIM) and (1‐(1,1‐dimethyl‐2‐oxo‐2‐phenylethyl)‐4‐dodecanoyloxymethyl‐1H‐1,2,4‐triazolium chloride, sPTM), derivatives of phenyl‐imidazolyl‐metyrapone (PIM) and phenyl‐1,2,4‐triazolyl‐metyrapone (PTM), respectively, were synthesized. Both sPIM and sPTM, designed as propesticides, inhibited E‐20‐M in vitro at 10−4 M concentration, which was unexpected since they had been expected to be inactive in vitro and to gain activity only within the organism. sPTM significantly delayed the pupariation of N bullata larvae and this effect could be reversed by the simultaneous application of 20‐hydroxyecdysone (20E), supporting the hypothesis that sPTM can act by interfering with the moulting hormone system. Due to this in vitro activity, sPTM and sPIM cannot be considered to be simple drug precursors, and their structure should contain structural elements (pharmacophores) responsible for the observed biological effects. In order to examine this hypothesis, derivatives of sPTM and sPIM were synthesised in which the hydrolytically labile N+—CH2O(CO)— moiety was changed to the more stable N+—CH2CH2(CO)—group. In three new stable derivatives, a dodecylamino or a phenyl group, respectively, is attached to the carbonyl group to obtain PTM and PIM derivatives quaternised with a 2‐dodecylcarbamoylethyl or a 3‐oxo‐3‐phenylpropyl group. In one derivative, the 2‐oxo‐2‐phenylethyl quaternising group has one fewer carbon atom. In addition to their moderate activity (LC50 = 10−6–10−5 M) against the red cotton bug Dysdercus cingulatus F, they delayed development and caused developmental abnormalities, including mortality in the pharate phase, mortality during moulting and wing deformations. These symptoms and the delay in development are characteristic of known compounds inhibiting the synthesis of 20E or interfering in the moulting processes. The facts that the frequent appearance of insects with developmental abnormalities and the delay in development could be reversed by co‐application of 20E indicate that the moulting system might be the site of action. We presume that the quaternary azole derivatives of PIM and PTM can themselves also interact with the moulting system.© 2003 Society of Chemical Industry
Actions of the sodium channel inhibitor 202W92 on rat midbrain dopaminergic neurons
Authors: Caputi Luigi , Hainsworth Atticus , Guatteo Ezia , Tozzi Alessandro , Stefani Alessandro , Spadoni Francesca , Leach Michael , Bernardi Giorgio , Mercuri Nicola B. 
Published: March 2003

AbstractExcessive glutamatergic activity is implicated in Parkinson's disease (PD) and sodium channel blockade, resulting in inhibition of glutamate release, is a potential therapeutic approach to PD therapy. Beneficial effects of riluzole and lamotrigine have been reported in animal models of PD, but these compounds have relatively low potency as sodium channel inhibitors and also inhibit N and P/Q‐type calcium channels. 202W92, a structural analog of lamotrigine, is a potent sodium channel inhibitor, with no effect on N, P/Q‐type channels. Here we present the effects of 202W92 on single patch‐clamped dopaminergic neurons. 202W92 (≥10 μM) inhibited spontaneous action potential firing and reduced amplitude and frequency of evoked action potentials. It also inhibited the frequency of 4‐aminopyridine (4‐AP)‐ and electrically evoked excitatory postsynaptic currents (EPSCs) and GABAergic inhibitory postsynaptic currents (IPSCs), with >80% inhibition at 10 μM (IC50 1.5 μM). EPSC and IPSC amplitudes were partially inhibited. 202W92 did not affect postsynaptic responses to locally applied glutamate and GABA, nor spontaneously occurring mini‐IPSCs. These actions of 202W92 are compatible with sodium channel inhibition and depression of transmitter release. Synapse 48:123–130, 2003. © 2003 Wiley‐Liss, Inc.
Effects of Goshajinkigan on Corneal Sensitivity, Superficial Punctate Keratopathy and Tear Secretion in Patients with Insulin-dependent Diabetes Mellitus
Authors: Nagaki Yasunori , Hayasaka Seiji , Hayasaka Yoriko , Kadoi Chiharu , Sekiya Nobuyasu , Terasawa Katsutoshi , Sakakibara Iwao 
Published: March 2003

Goshajinkigan (Niu-che-shen-qi-wan in Chinese), a traditional herbal medicine, has been used in Japan to treat clinical symptoms of diabetic neuropathy. A double-masked study was performed to evaluate its effects on corneal sensitivity, superficial punctate keratopathy and tear production in patients with insulin-dependent diabetes mellitus. Fifty diabetic patients were randomized into two groups: Group A, in which 25 patients received Goshajinkigan orally, 7.5 g/day for 3 months; Group B, in which 25 patients were orally administered placebo, 6.0 g/day for 3 months; and in Group C, 25 non-diabetic subjects were orally administered Goshajinkigan, 7.5 g/day for 3 months. Corneal sensitivity was measured with an aesthesiometer. The area of superficial punctate keratopathy was expressed as a fluorescein staining score. Reflex tearing was determined with a Schirmer test without anesthesia. Goshajinkigan was analyzed by high-performance liquid chromatography. Corneal thresholds after treatment with Goshajinkigan (2.03 g/mm2) in Group A were significantly lower than those before treatment (2.47 g/mm2). Those in Groups B and C did not change after treatment. Fluorescein staining scores after administration of Goshajinkigan (0.64) in Group A were significantly lower than those before treatment (1.32). Those in Groups B and C did not change after treatment. Schirmer test results after Goshajinkigan administration (11.0 mm/5 min) in Group A were significantly higher than those before treatment (9.3 mm/5 min). Those in Groups B and C did not change after treatment. Hemoglobin A1c levels in Groups A, B,and C did not change after treatment. Several components in Goshajinkigan were found on high performance liquid chromatography. In conclusion, Goshajinkigan improved ocular surface disorders in patients with insulin-dependent diabetes mellitus.
Stereospecific Reduction with Retention of Chiral Fluoral-derived 1,3-Oxazolidines with LiAlH4 : Asymmetric Synthesis of 1-Substituted 2,2,2-Trifluoroethylamines
Authors: Ishii Akihiro , Miyamoto Fumie , Higashiyama Kimio , Mikami Koichi 
Published: March 2003

Abstract
The asymmetric synthesis of 1-substituted 2,2,2-trifluoroethylamines from chiral 1,3-oxazolidines having trifluoromethyl group derived from trifluoromethyl ketones and (R)-phenylglycinol is described. The stereospecific reduction of chiral 1,3-oxazolidines with LiAlH4 proceeds in retention fashion.
The Enzymatic Transformation of Leaf-Movement Factor in Lespedeza cuneata G. Don Controlled by a Biological Clock
Authors: Ueda Minoru , Ohnuki Takashi , Yamamura Shosuke 
Published: March 2003

Abstract
We have shown that enzymatic transformation of potassium lespedezate (leaf-opening substance) to potassium 4-hydroxyphehylpyruvate in a nyctinastic plant, Lespedeza cuneata G. Don, controls the leaf-movement of the plant. By this transformation in the evening, the balance of concentration between leaf-opening substance and leaf-closing substance is inversed through a day. A biological clock should control the leaf-movement by activation or expression of the enzyme concerned in this step.
Covalent Immobilization of Oligonucleotides on Modified Glass/Silicon Surfaces for Solid-phase DNA Hybridization and Amplification
Authors: Yang Mengsu , Kong Richard Y C , Kazmi Najam , Leung Andrew K C 
Published: March 2003

Abstract
Glass slides and silicon chips were modified with aminosilane and various linker molecules to provide activated surfaces for covalent immobilization of oligonucleotides under ambient condition, and the surface-attached oligonucleotides remain active for solid-phase DNA hybridization and polymerase chain reaction.
Reaction of Thiopivalophenones with Benzyne. Formation of 2H-Benzo[b]thietes
Authors: Okuma Kentaro , Shiki Kyoko , Shioji Kosei 
Published: March 2003

Abstract
Reaction of thiopivalophenone with phenyl[2-(trimethylsilyl)phenyl]iodonium trifluoromethanesulfonate in the presence of tetrabutylammonium fluoride afforded the corresponding [2+2] cycloadduct, 2-tert-butyl-2-p-tolyl-2H-benzo[b]thiete, in 58% yield. On the other hand, reaction of thiopivalophenone with benzenediazonium 2-carboxylate gave 2-tert-butyl-2-p-tolyl-benzo[d][3,1]oxathiane-6-one in 82% yield. The difference in the reactivity might be owing to the leaving group ability.
Synthesis of Nanostructured Carbon Material by Electroreduction in Fused Alkali Carbonates
Authors: Kaplan Benjamin , Groult Henri , Komaba Shinichi , Kumagai Naoaki , Lantelme Frederic 
Published: March 2003

Abstract
Carbon fine powders were obtained by the electrochemical reduction of liquid ternary system lithium–sodium–potassium carbonates at 450 °C using nickel electrodes. The analysis of these powders by transmission electron microscopy and X-ray diffraction measurements revealed the coexistence of three different forms of carbon: graphite, amorphous carbon and carbon nanostructures. The third has an average diameter of about 10 nm and is self-organized into long “ropes”.
Polyslipping: A New Approach to Polyrotaxane-like Assemblies
Authors: Sohgawa Yow-hei , Fujimori Hiroki , Shoji Junko , Furusho Yoshio , Kihara Nobuhiro , Takata Toshikazu 
Published: March 2003

Abstract
“Polyslipping”, that is, multiple slipping of dumbbell components into macrocyclic ones having the appropriate size complementarity, of bis-ammonium salt 1 and bis-crown ether 5 in acetone or acetonitrile afforded polyrotaxane-like assembly 6, which quantitatively reverted to the monomers 1 and 5 by dissolving in DMSO.
A Strategy for Increasing Molecular Weight of Polyester by Lipase-Catalyzed Polymerization
Authors: Ebata Hiroki , Toshima Kazunobu , Matsumura Shuichi 
Published: March 2003

Abstract
A strategy for increasing the molecular weight of a polyester by lipase-catalyzed polymerization of a lactone and hydroxy acid was developed using azeotropic dehydration with toluene and a Dearn–Stark trap packed with molecular sieves. Thus, polycaprolactone (PCL) and poly(15-hydroxypentadecanoic acid) having number-average molecular weights of 81000 and 42000, respectively, were obtained by a 6-h polymerization at 70 °C.
Fabrication of Ultrathin, Protein-containing Films by Layer-by-Layer Assembly and Electrochemical Characterization of Hemoglobin Entrapped in the Film
Authors: Shang Libin , Liu Xinjian , Zhong Jun , Fan Chunhai , Suzuki Iwao , Li Genxi 
Published: March 2003

Abstract
Multilayers of hemoglobin were uniformly deposited on a pyrolytic graphite electrode surface through a layer-by-layer self-assembly approach. The well-known anionic polyelectrolyte, DNA, was used to attract cationic hemoglobin due to the strong electrostatic interaction between DNA and the protein. Interestingly, the electron transfer reactivity of hemoglobin was significantly improved in the film, which in turn facilitated the electrocatalytic reduction of nitric oxide.
Fast Reverse Design of 4D‐Printed Voxelized Composite Structures Using Deep Learning and Evolutionary Algorithm
Authors: Wang Mengtao , Liu Zaiyang , Furukawa Hidemitsu , Li Zhuo , Ge Yifei , Xu Yifan , Qiu Zhe , Tian Yang , Wang Zhongkui , Xu Ren , Meng Lin 
Published: February 2025

AbstractDesigning voxelized composite structures via 4D printing involves creating voxel units with distinct material properties that transform in response to stimuli; however, optimally distributing these properties to achieve specific target shapes remains a significant challenge. This study introduces an optimization method combining deep learning (DL) and an evolutionary algorithm, focusing on a solvent‐responsive hydrogel as the target material. A sequence‐enhanced parallel convolutional neural network is developed and generated a dataset through finite element simulations. This DL model enables high‐precision prediction of hydrogel deformation. Furthermore, a progressive evolutionary algorithm (PEA) is proposed by integrating the DL model to construct a DL‐PEA framework. This framework supports rapid reverse engineering of the desired shape, and the average design time for specified target shapes is reduced to ≈3.04 s. The present findings illustrate how 4D printing of optimized hydrogel designs can effectively transform in response to environmental stimuli. This work provides a new perspective on the application of hydrogels in 4D printing and presents an efficient tool for optimizing 4D‐printed voxelized composite structures.