bluuebunny/crossref_metadata_2025_split huggingface dataset:
A fourier transform infrared spectroscopic study of P2 protein in reconstituted myelin
Authors: Stuart B. H. 
Published: July 2007

AbstractThe secondary structure of P2 protein, isolated from bovine peripheral nervous system myelin, in reconstituted myelin was studied using Fourier transform infrared (FTIR) spectroscopy. Spectra of the protein in aqueous solution and in the lipid environment were compared and notable changes were observed. It was proposed that there are significant differences in the conformation of the protein in the contrasting environments. An increase in α‐helical structure was observed for the protein in myelin and the significant amount of β‐structure observed in aqueous solution was reduced. The degree of α‐helix appears to be related to the neuritogenic activity of the P2 protein. The findings of this study also support the view that the presence of both α‐helices and β‐structure plays a significant role in membrane proteins.
Lipid peroxidation both inhibits Ca2 ‐ATPase and increases Ca2 permeability of endoplasmic reticulum membrane
Authors: Račay Peter , Kaplán Peter , Mézešová Viera , Lehotský Ján 
Published: July 2007

AbstractIncubation of reticular membranes with Fe2+‐EDTA and H2O2 plus Fe2+‐EDTA at 37 °C for 30 min. led to the loss of membrane's efficiency to sequester Ca2+ to 21.8 % and 3.6 % of control values, respectively. The incubation of microsomes with Fe2+‐EDTA and H2O2 plus Fe2+‐EDTA also caused decrease of Ca2+‐ATPase activity; to 44.9 % and 44.4 % (measured under the same conditions as Ca2+‐uptake) or to 79.6 % and 62.1 % (uncoupled from Ca2+ transport by detergent). In addition, incubation of membranes with Fe2+‐EDTA and H2O2 plus Fe2+‐EDTA at 37 °C for 30 min. led to the increase of Ca2+ permeability to 125.1 % and 124.2 %, respectively. Preincubation of membranes with membrane‐soluble antioxidants (U‐74500A, U‐83836E, t‐butyl hydroxytoluene and stobadine) protected the reticular membranes against depression of Ca2+ uptake values and Ca2+‐ATPase inhibition in a dose and an antioxidant nature dependent manner. Our results indicate that both processes, Ca2+‐ATPase inhibition and increase of endoplasmic reticulum membrane Ca2+ permeability, participate in the lipid peroxidation induced loss of membrane's efficiency to sequester Ca2+.
Increased mitochondrial damage by lipid peroxidation in trophoblast cells of preeclamptic placentas
Authors: Morikawa Shigehiko , Kurauchi Osamu , Tanaka Masashi , Yoneda Makoto , Uchida Koji , Itakura Atsuo , Furugori Kazunori , Mizutani Shigehiko , Tomoda Yutaka 
Published: July 2007

AbstractLipid peroxides and their related free radicals have been implicated in the pathogenesis of placental dysfunction in preeclampsia. Recent studies suggest that the placenta is a source of the increased lipid peroxides in the maternal circulation of women with preeclampsia. We examined intracellular localization of 4‐hydroxy‐2‐nonenal (HNE: a major aldehydic product of lipid peroxidation)‐modified proteins in human placentas by immunohistochemistry, and immunoblotting. The trophoblast layer of the chorionic villi showed intense immunoreactivity for HNE‐modified proteins in 4 of 12 preeclamptic placentas, whereas no staining was observed in 12 normal placentas. Immunoblotting revealed that three immunoreactive proteins with apparent molecular mass of 110 kDa, 75 kDa, and 70 kDa were localized in the mitochondrial fraction. The present results indicate that the damage to mitochondrial proteins by lipid peroxidation byproducts and subsequent dysfunction of trophoblasts contribute to the pathophysiology of preeclampsia.
Characterization and expression analysis of a banana gene encoding 1‐aminocyclopropane‐1‐carboxylate oxidase
Authors: Huang Pung‐Ling , Do Yi‐Yin , Huang Fong‐Chin , Thay Te‐Shih , Chang Tang‐Wei 
Published: July 2007

AbstractA cDNA encoding the banana 1‐aminocyclopropane‐l‐carboxylate (ACC) oxidase has previously been isolated from a eDNA library that was constructed by extracting poly(A)+ RNA from peels of ripening banana. This cDNA, designated as pMAO2, has 1,199 bp and contains an open reading frame of 318 amino acids. In order to identify ripening‐related promoters of the banana ACC oxidase gene, pMAO2 was used as a probe to screen a banana genomic library constructed in the λEMBL3 vector. The banana ACC oxidase MA02 gene has four exons and three introns, with all of the boundaries between these introns and exons sharing a consensus dinucleotide sequence of GT‐AG. The expression of MA02 gene in banana begins after the onset of ripening (stage 2) and continues into later stages of the ripening process. The accumulation of MAO2 mRNA can be induced by 1 μl/l exogenous ethylene, and it reached steady state level when 100 μl/1 exogenous ethylene was present.
Membrane permeability transition as induced by dysfunction of the electron transport chain
Authors: Chávez Edmundo , Meléndez Esperanza , Zazueta Cecilia , Reyes‐Vivas Horacio , Perales Sofía G. 
Published: July 2007

AbstractThe results in this paper indicate that mitochondrial permeability transition is activated by dysfunction of the respiratory chain caused by anaerobiosis, exhaustion of the oxidative substrate, and antimycin A, in the presence of 100 μM Ca2+. Membrane damage coincides with the collapse of the electric gradient. The opening of the non‐selective pore is prevented by cyclosporin A.
The histamine releasers crotamine, protamine and compound 48/80 activate specific proteases and phospholipases A2
Authors: Mancin A. C. , Soares A. M. , Giglio C. A. , Andrião‐Escarso S. H. , Vieira C. A. 
Published: July 2007

AbstractCrotamine, a basic, myonecrotic, histamine‐releasing neurotoxin, was isolated from Crotalus durissus terrificus venom. Carboxypeptidase A was shown to be activated by crotamine when acting upon N‐carbobenzoxyglycil‐L‐phenylalanine. However the activity of carboxypeptidase B upon the substrate hippuryl‐L‐arginine was not enhanced by this toxin. The basic histamine releasers protamine and compound 48/80 also activated carboxypeptidase A. These three agents activated both α‐chymotrypsin when acting upon acetyl‐L‐tyrosine ethyl ester and also five snake venom phospholipase‐like myotoxins acting upon egg yolk phosphatidylcholine. These findings suggest that the action of these agents during histamine release may involve the participation of specific intermediary hydrolases which, upon activation, would enhance their cytolytic effects on the sequence of events which lead to granule extrusion and histamine release from mast cells.
Different effects of cell‐permeable ceramide analogs on platelet activation
Authors: Hashizume Tsutomu , Kageura Tadashi , Sato Takashi 
Published: July 2007

AbstractThe effects of cell‐permeable ceramide analogs on platelet responses induced by agonists were investigated. When washed rabbit platelets were pretreated with ceramide and then stimulated with thrombin or U46619, C2‐ceramide (N‐acetylsphingosine) dose‐dependently inhibited the aggregation and arachidonic acid liberation, whereas C6‐ceramide (N‐hexanoylsphingosine) and C8‐ceramide (N‐octanoylsphingosine) enhanced these responses. Furthermore, C6‐ceramide, but not C2‐ceramide, enhanced the increase in and prevented the progressive decrease in cytoplasmic free Ca2+ concentration induced by U46619. On the other hand, treatment with sphingomyelinase potentiated the aggregation in response to U46619. These results indicate that the effects of cell‐permeable ceramide analogs on platelet activation vary with N‐acyl chain length.
Chemical modification of dextransucrase from Leuconostoc mesenteroides NRRL B‐512F by pyridoxal 5′‐phosphate: Evidence for the presence of an essential lysine residue at the active site
Authors: Goyal Arun , Katiyar Sarvagya S. 
Published: July 2007

AbstractThe treatment of Leuconostoc mesenteroides NRRL B‐512F dextransucrase with lysine specific reagent, pyridoxal 5′‐phosphate (PLP) at pH 5.2 and 30°C resulted in the loss of enzyme activity. The inactivation by PLP could be reversed completely by dilution or dialysis. Sucrose as well as acceptor substrates, glucose and dextran protected the enzyme against inactivation by PLP. A statistical, kinetic analysis of the inactivation by PLP showed that one lysine residue is essential for the enzyme activity. All these results showed that one lysine residue present at the active is essential for the activity of dextransucrase.
Purification and properties of β‐N‐acetylhexosaminidase from cabbage
Authors: Chang Chen‐Tien , Young Fong‐Ping , Chang Ming‐Huey , Sung Hsien‐Yi 
Published: July 2007

Abstractβ‐N‐Acetylhexosaminidase was purified from the extract of cabbage by sequential steps of ammonium sulfate fractionation, chromatofocusing, DEAE‐Sepharose CL‐6B ion exchange chromatography and Sephacryl S‐200 HR gel filtration. By these steps, the purity of the enzyme increased by 256 fold with a recovery of 8%. The purified enzyme was homogeneous as examined by native PAGE. It showed an optimal pH of 4, an optimal temperature of 60 °C and a Km of 0.94 mM for hydrolysis of pNp‐β‐GlcNAc. The molecular mass of the enzyme determined from filtration through Sephacryl S‐200 was 150 kDa. Three subunits with molecular mass of 64, 57 and 51 kDa were observed as determined by SDS‐PAGE. NBS (0.025 mM), DEPC (3 mM) and WRK (30 mM) significantly inhibited the activity of the enzyme. The enzyme also showed activity toward pNp‐β‐GalNAc, N,N′‐diacetylchitobiose, N,N″‐triacetylchitotriose and N,N″,N…‐tetraacetyl chitotetraose but showed no activity toward pNp‐α‐GlcNAc, chitin and ethylene glycol chitin.
Chemical inactivation of bacterial GABA aminotransferase
Authors: Tunnicliff G. , Crites G. J. 
Published: July 2007

AbstractThe effects of three potential irreversible inhibitors of γ‐aminobutyrate aminotransferase from Pseudomonas fluorescens were studied in order to throw more light on the nature of the active site of the enzyme. The thiol group reagent mercuric chloride inactivated the enzyme in a concentration‐dependent manner. Inhibition kinetics were consistent with a simple bimolecular reaction. The second‐order rate constant was 4.2 × 103 ± 0.61 M‐1 see‐1. In contrast to either of the substrates, the cofactor pyridoxal 5′‐phosphate could protect the enzyme from the inhibition, suggesting cysteinyl residues are important for cofactor binding at the active site. p‐Chloromercuribenzoic acid produced a similar inactivation of the enzyme. 4‐Amino‐2‐fluorobutanoic acid also inhibited enzymic activity but in this case the inhibition was reversible and competitive with respect to γ‐aminobutyric acid (GABA). The inhibitor constant (Ki) was 0.83 ± 0.44 mM. We found no evidence that this fluorinated analogue of GABA could act as a substrate for the enzyme.
The β subunit of chloroplast ATP synthase (CF0CF1‐ATPase) is phosphorylated by casein kinase II
Authors: Kanekatsu Motoki , Saito Hitoshi , Motohashi Ken , Hisabori Toru 
Published: July 2007

AbstractWe studied a phosphate acceptor for casein kinase II (CK‐II) in chloroplasts, and found a 56 kDa protein (p56) as an acceptor, which was partially purified from the stroma of spinach chloroplasts. The N‐terminal amino acid sequence of p56 was identical with that of the β subunit of chloroplast ATP synthase (CF0CF1‐ATPase). In addition, the recombinant β subunit of CF1 was phosphorylated when the subunit was incubated with CK‐II. These results suggest that the β subunit of CF1 is a substrate protein of CK‐II in the chloroplast.
Skeletal muscle and liver lipoyllysine content in response to exercise, training and dietary α‐lipoic acid supplementation
Authors: Khanna Savita , Atalay Mustafa , Lodge John K. , Laaksonen David E. , Roy Sashwati , Hanninen Osmo , Packer Lester , Sen Chandan K. 
Published: July 2007

AbstractIn human cells, α‐lipoic acid (LA) is present in a bound lipoyllysine form in mitochondrial proteins that play a central role in oxidative metabolism. The possible effects of oral LA supplementation, a single bout of strenuous exercise and endurance exercise training on the lipoyllysine content in skeletal muscle and liver tissues of rat were examined. Incorporation of lipoyl moiety to tissue protein was not increased by enhanced abundance of LA in the diet. Endurance exercise training markedly increased lipoyllysine content in the liver at rest. A bout of exhaustive exercise also increased hepatic lipoyllysine content. A significant interaction of exhaustive exercise and training to increase tissue lipoyllysine content was evident. In vastus lateralis skeletal muscle, training did not influence tissue lipoyllysine content. A single bout of exhaustive exercise, however, clearly increased the level of lipoyllysine ill the muscle. Comparison of tissue lipoyllysine data with that of free or loosely‐bound LA results showed a clear lack of association between the two apparently related parameters. Tightly protein‐bound lipoyllysine pool in tissues appeared to be independent of the loosely‐bound or free LA status in the tissue.
Suppression of constitutive and inducible cytochrome P450 gene expression by α‐hederin in mice
Authors: Jeong Hye Gwang 
Published: July 2007

AbstractThe effects of α‐Hederin, a triterpenoid saponin which exists in some oriental herbs, on the expression of liver cytochrome P450s were examined in mice. The administration of α‐Hederin to mice significantly decreased the hepatic content of P450 and the activities of microsomal ethoxyresorufin O‐deethylase, methoxyresorufin O‐demethylase, and aniline hydroxylase, representative activities of cytochrome‐P4501A1, ‐P4501A2, and ‐P4502E1, respectively, in a dose‐ and time‐dependent manner. However, pentoxyresorufin O‐dealkylase, a representative activity of cytochrome P4502B1/2, was decreased to a lesser extent, α‐Hederin also decreased inducible monooxygenase activities in the same manner. Suppressions of P450 isozyme expression occurred in α‐Hederin treated hepatic microsomes, as determined by immunoblot analysis in a manner consistent with that of the enzyme activity levels. Levels of mRNA of P4501A1/2 and P4502B1/2 were also decreased by α‐Hederin as shown by Northern blot analysis. In contrast, the level of P4502E1 mRNA in the liver of α‐Hederin treated mice was unchanged. These results suggest that α‐Hederin may act as a more specific suppressor for P4501A and P4502E1 than P4502B and that the suppression involves decreases in mRNA levels except in the case of P4502E1.
Structural characteristics of tenecin 3, an insect antifungal protein
Authors: Lee Young‐Tae , Kim Dae‐Hee , Suh Jeong‐Yong , Chung Jae Hoon , Lee Bok Leul , Lee Younghoon , Choi Byong‐Seok 
Published: July 2007

AbstractTenecin 3, an antifungal protein, previously isolated from the insect Tenebrio molitor, inhibits growth of the fungus Candida albicans. However, the antifungal mechanism and functions of tenecin 3 remain unknown. As an initial step to study the mechanism and functions, physical and structural properties of tenecin 3 were examined by circular dichroism (CD) analysis and 2D nuclear overhauser effect spectroscopy. These analyses suggest that tenecin 3 has a propensity of random structure with very loose turn‐like elements. The CD results also indicate that this random structural propensity is not significantly affected by temperature, pH, and by the presence of organic solvents or sodium dodecyl sulfate (SDS) micelles. However, the hydrodynamic studies suggest that tenecin 3 is not in extended form in spite of its random structural feature.
Isolation and characterization of cDNA clone for human liver 10‐formyltetrahydrofolate dehydrogenase
Authors: Hong Mihui , Lee Younghee , Kim Jae Wha , Lim Jong‐Seok , Chang Sung Yeoul , Lee Kwang Soo , Paik Sang‐Gi , Choe In Seong 
Published: July 2007

AbstractA cDNA clone encoding 10‐formyltetrahydrofolate dehydrogenase (10‐FTHFDH) was isolated from a human fetal liver cDNA library. It contained the open reading frame of 2,709 base pairs and predicted a protein comprising 902 amino acids with a calculated molecular weight of 98,700 Da. The deduced protein showed about 93.6% homology (90.5% identity, 3.1% favored substitutions) when compared with rat 10‐FTHFDH. The distribution of 10‐FTHFDH transcript in various human tissues was studied by Northern blot analysis using poly(A+) RNAs from different tissues. The 10‐FTHFDH transcript with an approximate size of 2.7 kb was mainly expressed in human kidney, skeletal muscle, and liver and rarely expressed in other tissues.
The amino sequence of ovocleidin 17, a major protein of the avian eggshell calcified layer
Authors: Mann Karlheinz , Siedler Frank 
Published: July 2007

AbstractThe amino acid sequence of ovocleidin 17, a major protein of the chicken eggshell calcified layer, contains 142 amino acids including 2 phosphorylated serines. Data base searches show that ovocleidin belongs to a heterogeneous group of proteins consisting of a single C‐type lectin domain (CTL). The most similar sequences with an average of 30% identical amino acids were those of pancreatic stone protein (lithostathine) and lectins and anticoagulant proteins from snake venom.
Resveratrol inhibits copper ion‐induced and azo compound‐initiated oxidative modification of human low density lipoprotein
Authors: Zou Jian‐Gang , Huang Yuan‐Zhu , Chen Qi , Wei En‐Hui , Hsieh Tze‐chen , Wu Joseph M. 
Published: July 2007

AbstractTo investigate whether resveratrol, a polyphenolic compound in red wine, affects the oxidation of human low density lipoprotein (LDL), LDL purified from normolipidemic subjects was subjected to Cu2+‐induced and azo compound‐initiated oxidative modification, with and without the addition of varying concentrations of resveratrol. Modification of LDL was assessed by the formation of thiobarbituric acid reactive substances (TBARS) and changes in the relative electrophoretic mobility‐(REM) of LDL on agarose gels. Resveratrol (50 μM) reduced TBARS and REM of LDL during Cu2+‐induced oxidation by 70.5% and 42.3%, respectively (p<0.01), and prolonged the lag phase associated with the oxidative modification of LDL by copper ion or azo compound. These in vitro results suggest that resveratrol may afford protection of LDL against oxidative damage resulting from exposure to various environmental challenges, possibly by acting as a free radical scavenger.
The Role of Iron in Parkinson Disease and 1‐Methyl‐4‐Phenyl‐1,2,3,6‐Tetrahydropyridine Toxicity
Authors: Yantiri Ferda , Andersen Julie K. 
Published: July 2007

AbstractParkinson disease (PD) involves the specific degeneration of dopaminergic neurons ofthe pars compacta ofthe substantia nigra. Although the cause of the degeneration of nigrostrial dopaminergic neurons in PD is unknown, there is significant evidence to suggest that oxidative stress may be involved in this process. This review specifically examines the current status of evidence suggesting iron may contribute to oxidative damage associated with PD.
Phosphate‐Uptake Systems in Yarrowia lipolytica Cells Grown under Alkaline Conditions
Authors: Zvyagilskaya R. , Parchomenko O. , Persson B. L. 
Published: July 2007

AbstractIn this study we used a newly isolated Yarrowia lipolytica strain with a unique capacity to grow over a wide pH range (3.5‐10.5), which makes it an excellent model system for studying phosphate transport systems in cells grown under alkaline conditions. Phosphate uptake by Y. lipolytica yeast cells grown at pH 9.5‐10 was shown to be mediated by several kinetically discrete Na+‐dependent systems. One of these, a low‐affinity transporter, operates at high Pi concentrations and is, to our knowledge, here kinetically characterized for the first time. The other two high‐affinity systems are derepressible, come into play under conditions of Pi‐starvation, and appear to be controlled by the availability of extracellular Pi. They represent the first examples of high‐capacity, Na+‐driven Pi transport systems in an organism belonging to neither the animal nor the bacterial kingdoms.
Using the cash curve to discuss and discipline innovation investments
Authors: Andrew James P. , Sirkin Harold L. 
Published: July 2007

PurposeIntroduces the cash curve, a tool for monitoring the payback on innovation that has proved helpful in decision‐making, planning, analysis, and communication. The cash curve graphically plots cumulative cash flow over time.Design/methodology/approachDescribes the four “S” factors that have a direct impact on cash payback of innovation: start‐up costs or pre‐launch investment, also called start‐up or sunk costs; speed, or time to market; scale, or time to volume and support costsFindingsThe cash curve clarifies many of the managerial challenges, assumptions and trade‐offs that often get hidden when looking at spreadsheets of annual cash flows and projections.Practical implicationsShows managers how to use the cash curve to monitor what the payback will be if the assumptions they have made are right. This allows them to make a plan based on those assumptions, understand the impact of each assumption, determine which ones are most critical, test the ones with the biggest impact. With this perspective, the process can be managed, not simply reacted to.Originality/valueDemonstrates how to use the cash curve to address the fundamental challenge of innovation – to achieve the required cash payback by managing the overall process with the understanding that payback can come quite directly and quickly, but also that it may take longer, be much less certain, or come back to the company only indirectly, via other products and services.
Interview: After 15 editions, the authors of a strategic management textbook reflect
Authors: Abraham Stan , Leavy Brian 
Published: July 2007

PurposeTo find out, from the perspective of the authors of a well‐known textbook on strategic management, in what ways they think the field is changing.Design/methodology/approachStrategy & Leadership interviewed Arthur A. Thompson, Jr, A.J. Strickland III and John E. Gamble, the authors of the widely used textbook Crafting and Executing Strategy: Text and Readings, 15th edition (McGraw‐Hill/Irwin, 2006), to learn how they adapted the book to keep up with developments in the field.FindingsChanges include:new analytical tools and ways of looking at strategy issues; new concepts and terms appear in the literature; companies encounter new or different kinds of strategic issues; and each new edition has to include the latest and best examples of “strategy in action.”Practical implicationsSample practical suggestions: “A case can be made that a disproportionate amount of the research being published in today's “top tier” journals makes little difference to the practice of strategic management.” “To restore relevancy, business‐school deans and faculty must begin to place far higher scholarly value on research that truly advances the practice of management.” “I think we are now seeing a new trend, where more and more of the younger faculty lack training in the case method and are uncomfortable using it.”Originality/valueThe authors have watched strategic management literature develop and have a unique perspective on how the teaching of strategy has evolved.