bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of kidney and liver subacute toxicity induced by bezalip ‐ pravastatin. Lopid antihyperlipidaemic compounds in rats
Authors: Pispirigos K. , Simopoulos K. , Kouskoukis K. , Kounis N. , Avramopoulos A. 
Published: July 2007

AbstractRenal and hepatic subacute toxicity induced by the antihyperlipidaemic drugs: Bezalip ‐ Pravastatin and Lopid was investigated in rats using serum biochemical parameters. Toxicological evaluation was performed in serum samples following the administration of the therapeutic dose regimens of the compounds that were previously shown to be effective in inhibition of 3‐hydroxy‐methylgiutaryl coenzyme A (HMG CoA) reductase, the enzyme controlling the rate‐limiting step in the synthesis of cholesterol, and acyl‐ CoA cholesterol acyl transferase (ACAT) which converts intracellnlar free cholesterol to cholesterol ester. Renal and hepatic subacute toxicity was evaluated by measuring enzyme activity or concentrations of: alanine aminotransferace, alkaline phosphatase, asparate aminotransferase, γ‐glutamyltransferase, glucose, potassium, sodium, blood urea nitrogen, uric acid and creatinine. The use of the above serum biochemical parameters indicated that the overall toxicity impact of antihyperlipidaemic drugs was Bezalip = Pravastatin < Lopid.We have found that the Pravastatin ‐in contrast to the above antihyperlipidaemic drags‐ only transiently affects the biochemical parameters associated with toxicity, but, it affects some of the biochemical parameters associated with hepatic and renal toxicity, up to a significantly lower extent than the antihyperlipidaemic drags.
Isolation and characterization of an arginine ester hydrolase from Bothrops jararacussu venom which induces contractions of the isolated rat uterus
Authors: Andrião‐Escarso S. H. , Soares A. M. , Rodrigues V. M. , Mancin A. C. , Reis M. L. , Ballejo G. , Giglio J. R. 
Published: July 2007

AbstractThe isolation and partial characterization of a serine protease with arginine ester hydrolase activity from Bothrops jararacussu snake venom are described. The purification procedure consisted of a gel filtration of the crude venom on Sephadex G‐75 followed by an ion‐exchange chromatography of the active fraction on DEAE‐cellulose and a rechromatography on Bio‐Rex 70 resin. The esterase fraction (DI‐III), Mr=25,000 by SDS‐PAGE, showed proteolytic activity on fibrinogen and casein. After 2hr incubation, the Aα and Bβ chains of fibrinogen were intensely hydrolysed, while the γ, chain kept apparentely intact, even after 20hr of incubation. In spite of that, DI‐III did not clot fibrinogen. DI‐III induced edema in the rat paw. Although unable to release bradykinin, it induced contractions of the isolated rat uterus. DI‐III did not catalyse the hydrolysis of bradykinin. Its arginine ester hydrolase activity was completely inhibited by diisopropyl fluorophosphate after 1 hr incubation, but not by phenylmethylsulfonyl fluoride under the same conditions.
S‐Nitrosylation of Viral Proteins: Molecular Bases for Antiviral Effect of Nitric Oxide
Authors: Colasanti Marco , Persichini Tiziana , Venturini Giorgio , Ascenzi Paolo 
Published: July 2007

AbstractNitric oxide (NO) is considered an important signaling molecule implied in various different physiological processes, including nervous transmission, vascular regulation, and immune defence, as well as the pathogenesis of several diseases. NO reportedly also has an antiviral effect on several DNA and RNA virus families. The NO‐mediated S‐nitrosylation of viral and host (macro)molecules appears to be an intriguing general mechanism for the control of the virus life cycle. In this respect, NO is able to nitrosylate cysteine‐containing enzymes (e.g., proteases, reverse transcriptase, and ribonucleotide reductase). Moreover, zinc‐fingers and related domains present in enzymes (e.g., HIV‐1 encoded integrase or herpes simplex virus type‐1 heterotrimeric helicase primase complex) or nucleocapsid proteins may beconsidered as NO targets. Also, NO may regulate both host (e.g., nuclear factor‐kappaB) and viral‐encoded (e.g., HIV‐1 tat protein or Epstein‐Barr virus Zta) transcriptional factors that are involved in virus replication. Finally, NO‐mediated S‐nitrosylation of cysteine‐containing glycoproteins and hemagglutinin may also occur. Here, NO targets are summarised, and the molecular bases for the antiviral effect of NO are discussed.
Effects of Genetic and Diet‐Induced Obesity on Lipid Metabolism
Authors: Libinaki Roksan , Heffernan Mark , Jiang Woei‐Jia , Ogru Esra , Ignjatovic Vera , Gianello Robert , Trickey Lisa , Taylor Michelle , Ng Frank 
Published: July 2007

AbstractC57BL/6J obese (ob/ob) and lean mice fed ad libitum on a normal mouse chow diet (Normal), were compared with lean mice of the same age and strain fed ad libitum on a high‐fat diet, consisting of the Normal diet with the addition of beef lard (Lard), from age 3 months for 34 days. The lard‐fed mice were seen to have significantly higher (P < 0.05) body weight in this 34‐day period than that of the other two groups fed on the Normal diet. Epididymal fat depot and adipocyte cell size were significantly larger (P < 0.05) in the Lard‐fed lean mice and in the obese (ob/ob) mice than were those of the Normal‐fed lean mice. Dietary Lard intake did not significantly affect concentrations of plasma triglyceride although those of plasma cholesterol were significantly increased (P < 0.05). The development of obesity in these Lard‐fed mice appeared to be accelerated and significant.
New Chemiluminescence Assay for Linamarin
Authors: Ruengprapavut Sutarnthip , Chulavatnatol Montri 
Published: July 2007

AbstractA new chemiluminescence assay was developed for the quantitative determination of linamarin, a cyanogenic glucoside present in cassava. The assay involved hydrolysis of linamarin by a specific enzyme, linamarase, to release glucose, which was then quantitated by a chemiluminescence system consisting of glucose oxidaseperoxidase‐luminol.The new assay was more sensitive than the conventional spectrophotometric method for quantitating linamarin in cassava extracts. However, the following agents were found to interfere with the new assay:Vanadate,Mg2+,and Cu2+,were inhibitory to the luminescence of the H2O2‐peroxidase‐luminol system used in the coupling reaction, whereas EDTA and EGTA activated the system. In addition, Hg2+, which inhibits glucose oxidase, and Tris ion, which inhibits linamarase, both interfered with the new assay.
Evolutionary Conservation of the Membrane Fusion Machine
Authors: Poumbourios Pantelis , Center Rob J. , Wilson Kirilee A. , Kemp Bruce E. , Kobe Bostjan 
Published: July 2007

AbstractRecent structural studies of proteins mediating membrane fusion reveal intriguing similarities between diverse viral and mammalian systems. Particularly striking is the close similarity between the transmembrane envelope glycoproteins from the retrovirus HTLV‐1 and the filovirus Ebola. These similarities suggest similar mechanisms of membrane fusion. The model that fits most currently available data suggests fusion activation in viral systems is driven by a symmetrical conformational change triggered by an activation event such as receptor binding or a pH change. The mammalian vesicle fusion mediated by the SNARE protein complex most likely occurs by a similar mechanism but without symmetry constraints.
Biochemical Properties of the Protein Tyrosine Kinase of the Bacterium Acinetobacter johnsonii
Authors: Grangeasse C. , Vincent C. , Doublet P. , Cozzone A. J. , Duclos B. 
Published: July 2007

AbstractThe biochemical properties of the autophosphorylating protein tyrosine kinase of Acinetobacter johnsonii were analyzed in vitro. The study shows that the optimal pH value for the phosphorylation reaction is 7. The enzyme activity is stimulated by magnesium and, to a lesser extent, by manganese ions, whereas calcium ions have no effect. The phosphorylation process is rapid reaching a maximum in <2 min, and the enzyme is modified at multiple sites. Interestingly, the bacterial enzyme is insensitive to a series of molecules known to affect the activity of eukaryotic protein tyrosine kinases: genistein, quercetin, tosyllysine chloromethyl ketone, and vanadate. We concluded that, even though the overall phosphorylation reaction catalyzed by the A. johnsonii enzyme is identical to that occurring in eukaryotes, this bacterial kinase exhibits a number of specific properties and therefore probably belongs to a separate group in the general family of protein tyrosine kinases.
Real‐Time Oligonucleotide Hybridization Kinetics Monitored by Resonant Mirror Technique
Authors: Koval Vladimir V. , Gnedenko Oksana V. , Ivanov Yuri D. , Fedorova Olga S. , Archakov Alexander I. , Knorre Dimitri G. 
Published: July 2007

AbstractThe kinetics of hybridization of 11‐meric and 14‐meric oligonucleotides, dTGGGAAGAGGG (ODN‐11) and dTGGGAAGAGGGTCA (ODN‐14), with 14‐meric oligonucleotide dpTGACCCTCTTCCCA (p14) attached to the surface of a cuvette was studied by the resonant mirror method. The treatment of the experimental curves with exponential equations leads to the following values for association (kas) and dissociation (kdis) rate constants at 25 °C: kas = 219 +/‐ 39 and 183 +/‐ 162 M‐1s‐1, kdis = (2.0 +/‐ 0.4) 10‐3 and (4 +/‐ 1) 10‐4s‐1 for the duplexes (p14) (ODN‐11) and p14 (ODN14), respectively. The oligonucleotide dTGCCTTGAATGGGAAGAGGGTCA (ODN‐23), which forms a hairpin structure, does not associate with p14. The data were compared with the results of melting curve detection and temperature‐jump experiments. The association rate constants for ODN‐11 and ODN‐14 are much slower than those values in homogeneous aqueous solution. The dissociation rate constants have the same magnitude values as estimated by using association constants measured from melting curves but differ from the values estimated in temperature‐jump experiments.
Cloning and Characterization of Manganese Superoxide Dismutase Gene from Vibrio parahaemolyticus and Application to Preliminary Identification of Vibrio Strains
Authors: Shyu Yu‐Chiau , Lin Fu‐Pang 
Published: July 2007

AbstractThe sodA gene coding for manganese superoxide dismutase (Mn‐SOD) from the marine microorganism Vibrio parahaemolyticus was cloned, sequenced, and overexpressed in Escherichia coli by use of the pET20b (+) expression vector. The full‐length gene consisted of a 588‐bp open reading frame and encoded a polypeptide of 196 amino acid residues, with a calculated molecular mass of 21 713 Da. The recombinant enzyme was efficiently purified from crude E. coli cell lysate by metal ion affinity chromatography. The recombinant VPMn‐SOD resisted thermo‐denaturation up to 60 °C and was insensitive to such inhibitors as EDTA, NaN3 and diethyldithiocarbamic acid. The specificity of V. parahaemolyticus Mn‐SOD gene probe was analyzed by cross‐species polymerase chain reaction to provide information for Vibrio strain identification.
Substitution of Surface‐Exposed Framework Residues Alters Secretion of Recombinant Fusion Protein Fv/Tumor Necrosis Factor in Escherichia coli
Authors: Yang Junbao , Jia Zongchao , Xiang Jim 
Published: July 2007

AbstractSubstitution of hydrophobic residues with hydrophilic ones at surface‐exposed positions may influence the yield of antibody fragment expression in Escherichia coli by reducing its aggregation potential. We introduced such substitutions at 8 surface‐exposed framework region residues of a fusion protein Fv/Tumor Necrosis Factor, which resulted in the expression of 10 mutant fusion proteins (Mut 1‐10) in E. coli. Our results showed that expression levels of Mut 1‐3, with mutations of A9S, T18K, and G41D, respectively, decreased by 4‐ to 8‐fold, whereas expression levels of Mut 4, 9, and 10, with mutations of S60D/S70D, T28D, and G65D, respectively, were not affected. In contrast, mutation of F83A at light‐chain residue 83, which is usually buried at the variable/constant domain interface of antibody molecules but becomes surface‐exposed in recombinant Fv molecules, increased the expression level of Mut 5 by 4‐fold. Our results suggest that this important substitution of a hydrophobic residue with a hydrophilic one may also be applied to increase the secretion of other recombinant Fv molecules in E. coli periplasm.
A Mitochondrial Model for Premature Ageing of Somatically Cloned Mammals
Authors: Allen John F. , Allen Carol A. 
Published: July 2007

AbstractCloned sheep have recently been discovered to have an unexpectedly advanced biological age. We propose that the explanation is a simple consequence of inheritance of acquired, free radical‐induced cellular damage with somatic mitochondria that contribute to the mitochondrial population of cloned cells but not to zygotes produced by fertilization in normal sexual reproduction. Each increment of ageing in cloning experiments is therefore predicted to be maternally inherited. The hypothesis suggests practical ways of decreasing the effect. The hypothesis is itself a prediction of the recent proposal that mitochondria of the female germ line function primarily as genetic templates.
Activity of pp60c‐src and Association of pp60c‐src, pp54/58lyn, pp60fyn, and pp72syk with the Cytosḱeleton in Platelets Activated by Collagen
Authors: Kralisz Urszula , Cierniewski Czeslaw S. 
Published: July 2007

AbstractCollagen stimulation of platelets induced an increase in the specific activity of pp60c‐src immunoprecipitated from the Triton‐soluble fraction. The earliest time after collagen stimulation that an increase in pp60c‐src activity was observed was 30 s. However, the maximum activity of pp60c‐src in the Triton‐soluble fraction was observed 60 s after collagen stimulation. At this time an approximately twofold increase of pp60c‐src activity towards phosphorylation of KVEKIGEGTYGVVKK specific peptide and enolase and a 4.5‐fold increase towards phosphorylation of pp60c‐src itself was measured. Furthermore, the majority of pp60c‐src as well as pp54/58lyn, pp60fyn, and pp72syk were found in the Triton‐soluble fraction in resting platelets. Collagen induced, to different extents and velocities, translocation of all of these proteins from the Triton‐soluble fraction to the Triton‐insoluble, cytoskeleton‐rich, platelets fraction. These results provide direct evidence that collagen stimulation of platelets increases the tyrosine kinase activity of pp60c‐src and suggest that the platelet cytoskeleton plays an important role in collagen‐induced signal transduction by localizing signaling molecules.
Cloning and Characterization of a Novel cDNA Sequence Encoding the Precursor of a Novel Venom Peptide (BmKbpp) Related to a Bradykinin‐Potentiating Peptide from Chinese Scorpion Buthus martensii Karsch
Authors: Zeng Xian‐Chun , Li Wen‐Xin , Peng Fang , Zhu Zhi‐Hui 
Published: July 2007

AbstractBased on the amino acid sequence of a bradykinin‐potentiating peptide (Bpp) (peptide K‐12) from scorpion Buthus occitanus, a full‐length cDNA sequence encoding the precursor of a novel venom peptide (named BmKbpp) related to this Bpp, has been isolated and analyzed. The cDNA encodes a precursor of 72 amino acid residues, including a signal peptide of 22 residues and an extra Arg‐ArgArg tail at the C‐terminal end of the precursor, which have to be removed in the processing step. The C‐terminal region (21 residues) of the precursor is homologous (57% identical) with the sequence of peptide K‐12. Thus, according to the primary structure of the BmKbpp precursor, there may be a propeptide between the signal peptide and the putative mature BmKbpp at the C‐terminal region of the precursor.
The p66shc Protein: A Mediator of the Programmed Death of an Organism?
Authors: Skulachev Vladimir P. 
Published: July 2007

AbstractRecently knockout of the gene encoding an adaptor protein (p66shc) was shown both to prolong the life span of an animal and to prevent apoptosis of cells in response to added H2O2 (Migliaccio et al. [1999] Nature 402, 309?313). A hypothesis is put forward in which p66shc is assumed to be involved in phenoptosis, i.e., programmed death of an organism, mediated by the reactive oxygen species?dependent massive apoptosis in an organ of vital importance. The reactive oxygen species are suggested to oxidize phosphatidyl serine in the inner leaflet of the cell plasma membrane, resulting in appearance of this phospholipid in the outer membrane leaflet, an effect recognized by a special receptor and causing the p66shc phosphorylation at a serine residue. Serine‐phosphorylated p66shc there is proposed to block mitosis and initiate apoptosis. The large‐scale apoptosis leads to phenoptosis and, hence, shortens the life span of the organism.
Reverse Transcription of a Naturally Occurring Nonretroviral RNA Produces a Precise Deletion in the Majority of Its cDNA Products
Authors: Johnson Karyn N. , Gordon Karl H. J. , Hanzlik Terry N. 
Published: July 2007

AbstractA precise, reproducible deletion made during in vitro reverse transcription of RNA2 from the icosahedral positive‐stranded Helicoverpa armigera stunt virus (Tetraviridae) is described. The deletion, located between two hexamer repeats, is a 50‐base sequence that includes one copy of the hexamer repeat. Only the Moloney murine leukemia virus reverse transcriptase and its derivative Superscript I, carrying a deletion of the carboxy‐terminal RNase H region, showed this response, indicating a template‐switching mechanism different from one proposed that involves a RNase H? dependent strand transfer. Superscript II, however, which carries point mutations to reduce RNase H activity, does not cause a deletion. A possible mechanism involves the enzyme pausing at the 3′ side of a stem‐loop structure and the 3′ end of the nascent DNA strand separating from the template and reannealing to the upstream hexamer repeat.
An RNA Polymerase II Complex Containing Capping Enzymes and Viral Oncoproteins
Authors: Cabrejos Maria Eugenia , Maldonado Edio 
Published: July 2007

AbstractThe aim of this work was to identify proteins from Adenovirus 2‐infected HeLa cell extracts that interact with the carboxyl‐terminal domain of the largest subunit of RNA polymerase II. First, a mammalian RNA polymerase II complex was isolated from Adenovirus 2‐infected HeLa cell extracts by affinity chromatography against the carboxyl‐terminal domain of the largest subunit of RNA polymerase II, followed by chromatography on a Mono S fast protein liquid chromatographic column. Second, the isolated complex was further characterized by Western blot analysis, the formation of a GMP‐protein complex, and transcriptional activity. The isolated complex contains general transcription factors, chromatin‐remodeling factors, histone acetyltransferases, Srbs, capping enzymes, and E1A viral oncoproteins. The RNA polymerase II complex is active in transcription when supplemented with recombinant transcription factor IIB.
Interaction of Bacterial Flagellum Filaments with Skeletal Muscle Myosin
Authors: Novikova Nadezhda A. , Levitsky Dmitrii I. , Metlina Antonina L. , Poglazov Boris F. 
Published: July 2007

AbstractInteraction of isolated bacterial flagellum filaments (BFF) and intact flagella from E. coli MS 1350 and B. brevis G.‐B.p+ with rabbit skeletal myosin was studied. BFF were shown to coprecipitate with myosin (but not with isolated myosin rod) at low ionic strength, that is, under conditions of myosin aggregation. The data of electron microscopy indicate that filaments of intact bacterial flagella interact with isolated myosin heads (myosin subfragment 1, S1), and this interaction is fully prevented by addition of Mg2+‐ATP. Addition of BFF inhibited both K+‐EDTA‐and Ca2+‐ATPase activity of skeletal muscle myosin, but had no effect on its Mg2+‐ATPase activity. Monomeric flagellin did not coprecipitate with myosin and had no effect on its ATPase activities. BFF were shown to compete with F‐actin in myosin binding. It is concluded that BFF interact with myosin heads and affect their ATPase activity. Thus, BFF composed of a single protein flagellin are in many respects similar to actin filaments. Common origin of actin and flagellin may be a reason for this similarity.
Changes in working with gender equality in management in Sweden
Authors: Wahl Anna , Höök Pia 
Published: July 2007

PurposeThe article is based on a study of the changes in the methods used in working with gender equality issues in management in Sweden from the early 1990s until the early 2000s.Design/methodology/approachThe material consists of interviews with 20 people who work either as employees in organisations or as business owners/consultants in the field of increasing the numbers of women at executive levels. In the article, they are referred to as “equality professionals”.FindingsThe changes that have taken place may be described in two ways – partly changes in how the work is pursued within organisations, and partly through the work having moved to other arenas. When summarising the material, four overriding trends can be identified that characterise the changes in gender equality work: (1) a more radical understanding of gender equality among groups positive to change; (2) a professionalisation of gender equality work; (3) a shift from organisational projects to working with individuals; (4) a shift from organisational projects to influencing organisations from other public arenas.Research limitations/implications – Its focus on Sweden as well as its focus on a specific, quite small (20) group of people.Practical implicationsUseful and interesting for those working with gender equality, especially as Sweden is sometimes put forward as “the world's most gender equal country”.Originality/valueThe article has value because it shows the Swedish context as well as the longitudinal approach, i.e. that the study focuses on a 10‐year period (1993‐2002) and includes comparative material.
Identification of a QTL on BTA20 affecting susceptibility toMycobacterium aviumssp.paratuberculosisinfection in US Holsteins
Authors: Gonda M. G. , Kirkpatrick B. W. , Shook G. E. , Collins M. T. 
Published: July 2007

SummaryThe objective of this study was to identify QTL affecting susceptibility toMycobacterium paratuberculosisinfection in US Holsteins. Twelve paternal half‐sib families were selected for the study based on large numbers of daughters in production and limited relationships among sires. Serum and faecal samples from 4350 daughters of these 12 sires were obtained for disease testing. Case definition for an infected cow was an ELISA sample‐to‐positive ratio ≥0.25, a positive faecal culture or both. Three families were selected for genotyping based on a high apparent prevalence (6.8–10.4% infected cows), high faecal culture prevalence (46.2–52.9% positive faecal cultures) and large numbers of daughters tested for disease (264–585). DNA pooling was used to genotype cows, with an average of 159 microsatellites within each sire family. Infected cows (the positive pool) were matched with two of their non‐infected herdmates in the same lactation (the negative pool) to control for herd and age effects. Eight chromosomal regions putatively linked with susceptibility toM. paratuberculosisinfection were identified using aZ‐test (P < 0.01). Significant results were more rigorously tested by individually genotyping cows with three to five informative microsatellites within 15 cM of the significant markers identified with the DNA pools. Probability of infection based on both diagnostic tests was estimated for each individual and used as the dependent variable for interval mapping. Based on this analysis, evidence for the presence of a QTL segregating within families on BTA20 was found (chromosome‐wideP‐value = 0.0319).