bluuebunny/crossref_metadata_2025_split huggingface dataset:
Community Health Workers and the Drug Problem
Authors: O'Neill Pat 
Published: July 2007

Abstract: Denial about the habitual misuse of substances is a standard feature of addictive behaviour. Denial by a collective of addicts when they form a sufficient proportion can then become a societal norm. This societal denial is a major factor in the conspiracy of silence.Breaching denial is a necessary first step for addicted people seeking change. The community response to addictive behaviour must contain the essential steps as defined in the structured intervention technique (“Alconfrontation”) for the individual. They are: (i) definition and acceptance of the nature of the problem; (ii) education about addictive behaviour and the substances concerned, within a relevant perspective; (iii) clarification of the options and objectives; and (iv) contract making.It is possible for communities to achieve collective change if enough significant catalytic individuals and agencies strive to do so.In relation to drink driving and analgesic abuse there have already been significant advances. Cigarette smoking has declined rapidly and this wind of change can be fanned. Armidale in New South wales has a Bicentennial objective to be visibly free of cigarette smoking with its theme “Armidale Leads the Smoke‐Free World”.Innumerable surveys have confirmed that the major factor in society's problems is substance abuse. What is needed now is a core of catalysts to provoke change by increasing awareness, by appropriate education, by exploring tactics for change and by pushing for commitment and contract for change.
Genetic Variations in Vascular Endothelial Growth Factor and Endothelial Nitric Oxide Synthase and Their Contributions to Human Disease
Authors: GERRITSEN MARY E. 
Published: July 2007

ABSTRACTThis review addresses a rapidly growing area of vascular biology, i.e. genomic variations in vascular genes that underlie different human phenotypes. Two of the most important molecular in vascular biology, endothelial nitric oxide synthase (eNOS) and vascular endothelial cell growth factor (VEGF) are discussed. Variations in the eNOS gene have been correlated with a number of human diseases including hypertension, coronary vasospasm, smoking dependent risk of coronary disease, myocardial infarction and placental disruption. Similarly, variations in the VEGF gene have been associated with increased risk of various cancers, DiGeorge syndrome, psoriasis, diabetic renal disease and amyotropic lateral sclerosis. Understanding the molecular basis of these genetic variations and how contribute to the pathophysiology provides new and important insights into human disease.
Characterisation of lipid‐protein interactions using a surface plasmon resonance biosensor
Authors: Rajaram O. V. , Sawyer W. H. 
Published: July 2007

AbstractThe binding of proteins to lipid surfaces is of fundamental importance when considering the mechanisms of lipases and lipid transfer proteins. Current procedures for determining the binding constants suffer from problems related to poor sensitivity, poor reproducibility and to the use of restrictive assumptions in the analysis. We demonstrate here the use of the surface plasmon resonance biosensor to determine the association and dissociation kinetics of binding of cholesteryl ester transfer protein to the surface of emulsion particles of defined size and composition. Uncertainty about the emulsion valency, that is, the number of sites on the lipid particle occupied by the immobilised transfer protein on the biosensor surface, means that the association kinetics can only be characterised in terms of the product of the association rate constant and the concentration of sites, whereas the dissociation rate constant can be obtained unambiguously. The technique will prove useful in characterising the binding of proteins to lipid surfaces.
Interactions of trans‐acting factors(s) with the estradiol response element and nuclear factor 1 of the vitellogenin II gene of Japanese quail
Authors: Gupta Sanjay , Upadhayay Rashmi , Kanungo M. S. 
Published: July 2007

AbstractThis study was directed at achieving an understanding of the mechanisms by which steroid hormones control the synthesis of vitellogenin (VTG) protein in the liver of the Japanese quail. Northern hybridization shows that administration of estradiol alone or with progesterone stimulates the synthesis of VTG mRNA. Gel mobility shift assay of DNA fragments containing the ERE and NF1 shows that estradiol alone or with progesterone increases the levels of nuclear proteins that bind to these cis‐acting elements of the promoter of VTG gene. The cooperative effect of the two hormones seen at the level of expression of the VTG gene may be due to protein‐protein interactions of trans‐acting factors that bind to ERE and NF 1.
Oxidative damages by iron‐chelate complexes depend on the interaction with the target molecules
Authors: Asaumi Akira , Ogino Tetsuya , Akiyama Takashi , Kawabata Teruyuki , Okada Shigeru 
Published: July 2007

AbstractTo elucidate that in iron‐catalyzed oxidative damage the interaction of iron complex with the target molecules is important, the oxidative damage to plasmid DNA, protein and fatty acid has been compared using iron‐chelate complexes with nitrilotriacetic acid (nta), citric acid, ethylenediamine‐N,N′‐diacetic acid (edda) and diethylenetriamine‐N,N,N′,N″,N″‐pentaacetic acid (dtpa). In the presence of hydrogen peroxide, plasmid pBR322 strand breaks occurred in the order of Fe‐edda > Fe‐citrate > Fe‐nta >> Fe‐dtpa. However, fragmentation of bovine serum albumin and diene conjugation of linoleic acid micelle occurred in the order of Fe‐nta > Fe‐edda >> Fe‐citrate > Fe‐dtpa = 0, which were similar to hydroxyl radical production by these iron complexes and H2O2. Bleomycin‐detectable free radical‐promoting irons in these iron complexes were about 85% of iron in Fe‐nta, Fe‐citrate and Fe‐edda, and only about 33% in Fe‐dtpa. Not only hydroxyl radical productivity and free radical‐promoting iron content in iron complex, but also the interaction of the complex with the target molecules determines the iron‐catalyzed oxidative damage.
Estrogen surge: A regulatory switch for superoxide radical generation at implantation
Authors: Laloraya Malini , Jain Sudhir , Thomas Monzy , Kopergaonkar Swati , Pradeep Kumar G. 
Published: July 2007

AbstractThis study is undertaken to identify the regulatory switch for the activation of superoxide radical generation pathway and repression of superoxide dismutase (SOD) at the time of implantation using estrogen as a control factor and delayed implantation as a model system. The results revealed high SOD activity and negligible oxyradical generation in progesterone‐treated animals on day‐5 and day‐8 (delayed implantation) while an enormous rise in oxyradical generation and an abrupt fall in SOD in animals which received both estrogen and progesterone injections were observed on days 5 and 8 of pregnancy. These results strongly suggest that estrogen regulates superoxide anion radical generation by lowering the SOD activity.
Role of the reductant substrates on the inactivation of horseradish peroxidase by m‐Chloroperoxybenzoic acid
Authors: Arnao M. B. , Garcia‐Cánovas F. , Acosta M. 
Published: July 2007

AbstractHorseradish peroxidase reacts with H2O2 and other hydroperoxides to form Compound I, the first active enzymatic form. m‐Chloroperoxybenzoic acid, a xenobiotic hydroperoxide, acts as an oxidant substrate of horseradish peroxidase. However, this hydroperoxide is also a powerful inactivator of the enzyme and in this sense is more effective than H2O2. The coupled reductant substrates used in the peroxidatic reaction protect the enzyme from the inactivating process.A reaction mechanism is proposed with two competitive routes: one catalytic and one inactivating. Using a kinetic approach, the ratio between the hydroperoxide and the reductant substrate appears to be a decisive factor in the catalytic turnover of the enzyme.The role of the reductant substrates in protecting the enzyme, and the physiological and biotechnological implications of this process are discussed.
Regulation of the activity of M‐phase promoting factor through protein kinase A‐mediated pathway in LP1‐1 cells
Authors: Oh Won Jong , Joe Cheol O. , Choi Kyung Hee 
Published: July 2007

AbstractTreatment of cAMP analogs, dibutyryl cAMP and 8‐bromo‐cAMP, was found to inhibit the proliferation of mouse fibroblast LP1‐1 cells and the p34cdc2 kinase activity of M‐phase promoting factor (MPF). However, it showed relatively little effect on expression of the cyclin B1 and cdc2 genes. On the other hand, when the nuclear extracts obtained from the cells at early G2 phase were treated with cAMP analogs, the kinase activity was significantly decreased as compared to the untreated control. Furthermore, the inhibitory effect of cAMP analogs could be reversed upon treating with okadaic acid even in the presence of the cAMP analogs, implying that cdc25 remains in an active form. In addition, the treatment of okadaic acid stimulated the cell progression. These results suggest that down‐regulation of MPF activity through protein kinase A‐mediated pathway is under post‐translational control and cdc25 activation pathway involving okadaic acid‐sensitive phosphatase play a role in the regulation of MPF activity.
Zearalenone ‐ Induced uncoupling in plant mitochondria is sensitive to 6‐ketocholestanol
Authors: Macri F. , Vianello A. , Braidot E. , Petrussa E. , Mokhova E. N. 
Published: July 2007

AbstractZearalenone (F‐2) is a mycotoxin which acts as a protonophoric uncoupler in plant mitochondria [Macri, F. and Vianello, A., (1990) J. Plant Physiol. 136, 754‐757]. In the present paper, the mechanism of F‐2‐induced uncoupling in pea mitochondria was studied. The uncoupling by F‐2 was partially reversed by 6‐ketocholestanol (kCh) under conditions in which kCh completely reversed the FCCP‐induced uncoupling and almost did not affect the palmitate‐induced uncoupling. Recoupling effects of carboxyatractylate, ADP and cyclosporin A were small and could not essentially decrease the kCh‐insensitive part of F‐2‐induced uncoupling. It is suggested that a protein, mediating kCh‐sensitive uncoupling, is involved in the F‐2 effect in plant mitochondria.
Interaction of myosin subfragment 1 with F‐actin studied by differential scanning calorimetry
Authors: Nikolaeva Olga P. , Orlov Victor N. , Dedova Irina V. , Drachev Vladimir A. , Levitsky Dmitrii I. 
Published: July 2007

AbstractThe thermal unfolding of the myosin subfragment 1 (S1) and of filamentous actin (F‐actin) in their strong complex obtained in the presence of ADP was studied by differential scanning calorimetry (DSC). It is shown that in the acto‐S1 complexes S1 and F‐actin melt separately, and thermal transitions of each protein can be easily followed. Interaction of S1 with F‐actin significantly increases S1 thermal stability and also affects the thermal stability of F‐actin. Although S1 unfolds at much lower temperature than F‐actin, the molecules of S1 remain bound to F‐actin even after full denaturation. Under these conditions S1 may induce cross‐linking between actin filaments. It is concluded that DSC studies on the acto‐S1 complexes offer a new and promising approach to investigate the structural changes which occur in the myosin head and in F‐actin due to their interaction.
Mapping the 90 kDa heat shock protein binding region of the Ah receptor
Authors: Perdew Gary H. , Bradfield Christopher A. 
Published: July 2007

AbstractExpression of a series of Ah receptor (AhR) deletion mutants in an in vitro translation system has been previously used to map several functional domains of the murine AhR (Dolwick et al. (1993) Proc. Natl. Acad. Sci. USA 90, 8566‐8570). In this report, quantitative immunoprecipitation of 90‐kDa heat shock protein (hsp90) from reticulocyte lysate allowed us to measure the level of the AhR and AhR deletion mutants complexed with hsp90. After translation of a series of deletion mutants it was determined that there are two distinct domains important in forming a stable AhR/Hsp90 complex, corresponding to amino acid sequences 1‐166 and 289‐347 of the AhR. Neither ARNT, nor Per were able to stably interact with hsp90. Thus, the AhR appears to be a unique member of the PAS domain family of proteins that binds a known ligand and stably interacts with hsp90.
Molecular cloning and expression of a cDNA encoding a protein tyrosine phosphatase from mouse brain
Authors: Park Kyung Soo , Kim Yeon Woong , Kim Choong Won , Kang Dae Ook , Byun Si Myung 
Published: July 2007

AbstractA mouse brain cDNA library was screened with a radioisotope‐labeled probe of human placental protein tyrosine phosphatase. The isolated clone (MBPTP1B) was found to contain an open reading frame of 1,296 nucleotides as well as 5′ (709 nucleotides) and 3′ (341 nucleotides) non‐coding regions. This cDNA encodes a PTP of 432 amino acids having a mass of 49,563 daltons and exhibiting 83% and 93.5% sequence identity to that of human PTP1B and rat PTP1, respectively. The expression of the cDNA in yeast was identified by western blot analysis and PTP activity assay.
Hyaluronic acid induced hyaluronic acid binding protein phosphorylation and inositol triphosphate formation in lymphocytes
Authors: Rao Ch. Mastan , Deb Tushar Baran , Datta Kasturi 
Published: July 2007

AbstractIn this report, the role of 34 kDa HA‐binding protein in hyaluronic acid‐induced cellular signalling in lymphocytes has been examined. The binding of 125I‐HA to lymphocytes in vivo was found to be inhibited by pre‐incubation of the cells with anti‐34 kDa HA‐binding protein antibodies, thus confirming 34 kDa HA‐binding protein as the specific HA‐receptor in lymphocytes. This observation was substantiated by anti‐34 kDa HA‐binding protein antibodies immunoblotting and 125I‐HA ligand blotting of lymphocytes cell lysate. The HA‐induced cell aggregation, tyrosine phosphorylation and cytoskeletal protein phosphorylation demonstrate the HA‐induced early cellular signalling events in lymphocytes. Further, to study the involvement of 34 kDa HA‐binding protein in mitogen induced lymphocyte signalling, we studied in vivo phosphorylation and secondary messenger formation. The enhanced 34 kDa HA‐binding protein phosphorylation by HA and the inhibition of cellular aggregation and IP3 formation by anti‐HA‐binding protein antibodies revealed that 34 kDa HA‐binding protein is one of the potential mediators in HA‐induced signal transduction.
Development of a metallothionein based heavy metal biosorbent
Authors: Pazirandeh Mehran 
Published: July 2007

AbstractThe potential utility of a recombinant E. coli expressing the Neurospora crassa metallothionein gene (NCP) as a heavy metal biosorbent was investigated. It was shown that the NCP was capable of efficiently removing low levels of several metals (including cadmium, lead, and mercury) from solutions. The reusability of the NCP was demonstrated through 5 cycles of metal binding, stripping with dilute acid, and regeneration of the binding sites with out any adverse effect on the metal binding activity. The NCP was successfully encapsulated in alginate and acrylamide without any inhibitory effect on its metal uptake activity. Furthermore, the metal uptake activity of the NCP was shown to be metabolism independent and resistant to solvents and other compounds (eg. polyaromatic hydrocarbons) which are often present along with heavy metals in waste waters thereby creating the potential for non‐viable, encapsulated cells to be used.
The fungus Gibberella fujikuroi produces copper/topaquinone‐containing amine oxidase when induced by n‐butylamine
Authors: Frébort Ivo , Matsushita Kazunobu , Adachi Osao 
Published: July 2007

AbstractCrude extract of Gibberella fujikuroi AKU 3802 mycelium induced with n‐butylamine showed a single amine oxidase activity band in a non‐denaturing gel that cross‐reacted with the antibody against copper/topaquinone‐containing amine oxidase from Aspergillus niger. The enzyme was purified by a procedure involving four chromatographic steps. Purified enzyme was pink with an absorption maximum at 490 nm. Molecular mass of 135 kDa estimated by gel chromatography and 70 kDa found by SDS‐PAGE confirmed the dimeric structure of the enzyme. The enzyme readily oxidized n‐hexylamine, n‐butylamine, benzylamine and histamine, but not spermine or spermidine. Inactivation by carbonyl reagents and copper chelators suggested the presence of a copper/topaquinone cofactor. Spectrophotometric titration by p‐nitrophenylhydrazine showed one reactive carbonyl group per subunit and redox‐cyclic quinone staining confirmed the presence of a quinone cofactor, pH‐dependent shift of the absorption spectrum of the enzyme p‐nitrophenylhydrazone (465 nm at neutral to 580 nm at alkaline pH) supports the identity of the cofactor with topaquinone. The N‐terminal amino acid sequence of the enzyme showed high similarity to other microbial copper/topaquinone‐containing amine oxidases.
Effect of polyanions on ferricytochrome c
Authors: Sedlák Erik 
Published: July 2007

AbstractEffects of two polyanions (heparin, Nation) on absorption and CD spectra in the Soret region, and on fluorescence of ferricytochrome c were investigated. The conformational state of ferricyt c in the complexes with studied polyanions is significantly different. Whereas heparin affects the structure in the heme region of ferricyt c only slightly (ferricyt c remains in a native‐like state), the influence of Nation is more expressive (the Met‐80 ‐ heine iron bond and the deeply buried region around Trp‐59 are perturbed). Shift of the pK of the transition from neutral low‐spin state to acidic high‐spin state to higher pH values was observed.
Separation of three P450 isozymes from liver microsomes of gilthead seabream treated with ß‐NF and partial purification of cytochrome P4501A1
Authors: Sen Alaattin , Arıç Emel 
Published: July 2007

AbstractThree distinct cytochrome P450 isozymes, P4501A1, P4502B and an unidentified P450 isozyme were separated and isolated from ß‐NF‐treated gilthead seabream liver microsomes. Cytochrome P4501A1 was partially purified from ß‐NF‐treated gilthead seabream liver microsomes in the presence of detergents Emulgen 913 and cholate and protease inhibitors using two DEAE‐cellulose, Porapak Q and two hydroxylapatite column chromatographies. The overall yield of purified P4501A1 was 1.2% with respect to microsomal total P450 with a specific content of 3 nmol/mg protein. The purified P4501A1 was characterized with respect to spectral, electrophoretic, biocatalytic and immunochemical properties, which are found to be similar to P4501Als purified from other teleost species such as trout, scup, cod and perch suggesting that the P450 we have purified belongs to CYP1A1.
Free radical‐induced inhibition of ATP diphosphohydrolase activity (EC 3.6.1.5) from rat blood platelets
Authors: Frassetto Silvana S. , Dias Renato D. , Sarkis João J. F. 
Published: July 2007

AbstractIn the present report we demonstrate the in vitro effects of free radicals on an ecto‐ATP diphosphohydrolase activity (apyrase, EC 3.6.1.5) from rat blood platelets. Rat blood platelets were exposed to an oxidant‐generating system (H202 / Fe2+ / ascorbate) and the ATP diphosphohydrolase activity was inhibited. The enzyme inhibition was prevented by glutathione (GSH) and cysteine but not by trolox as a vitamin E analogue. The TBARS (thiobarbituric acid reactive substances) assay and the determination of sulphydryl groups indicate that the inhibition of the enzyme activity in resting platelets is not related to lipid peroxidation or to oxidation of sulphydryl residues. These results demonstrate the susceptibility of ATP diphosphohydrotase activity from platelets to free radicals and suggest that amino acid residues which are essential for the enzyme function are probably modified.
Effect on product specificity of cyclodextrin glycosyltransferase by site‐directed mutagenesis
Authors: Kim Young Ho , Bae Kwang Hee , Kim Tae Jip , Park Kwan Hwa , Lee Hyun Soo , Byun Si Myung 
Published: July 2007

AbstractCyclodextrin glycosyltransferase (CGTase; EC 2.4.1.19) catalyzes the degradation of starch into cyclodextrins through an intrarnolecular transglycosylation reaction. Tyr‐89, Asn‐94, and Tyr‐100 are located near the putative active center. To analyze their roles in product specificity, Tyr‐89, Asn‐94, and Tyr‐100 of CGTase from alkalophilic Bacillus sp. 1‐5 were replaced with different amino acids. Among the mutants, the N94S mutant protein produced about two times more α‐cyclodextrin than the wild‐type at all incubation times. The Y89F and Y100F mutant proteins were changed to more β‐specific enzymes. From these results it is suggested that the changing of the residues located at the near active site can change the product specificity of CGTase.
Molecular cloning and nucleotide sequencing of bioF (7‐keto‐8‐amino pelargonic acid synthetase), BioC and BioD (dethiobiotin synthetase) genes of Erwinia herbicola
Authors: Wu Chwen‐Huey , Bao Yu‐Yen , Shao Chung‐Ping , Shiuan David 
Published: July 2007

AbstractThe biotin operon of Erwinia herbicola Eho 10 was cloned and characterized by complementation of E. coli biotin mutants. The operon was found to contain five genes arranged in the order, bioABFCD. The nucleotide sequences of bioF (7‐keto‐8‐aminopelargonic acid synthetase), bioC and bioD (dethiobiotin synthetase) were determined and analyzed. The nucleotide sequences and deduced amino acid sequences of bioFCD were compared with the corresponding sequences from Escherichia coli, Bacillus sphaericus, Serratia marcescens and Brevibacterium flavum.
Application of hammerhead ribozymes for structural studies of ribosomal 5S RNAs
Authors: Szymañski Maciej , Fürste Jens‐Peter , Barciszewska Miroslawa Z. , Erdmann Volker A. , Barciszewski Jan 
Published: July 2007

AbstractWe synthesized and used hammerhead ribozymes designed for the GUC and AUC target sequences located in the terminal loop C of animal and plant 5S rRNAs to verify its involvement in a higher order structure formation of ribosomal RNA. The activity of both GUC and AUC specific ribozymes were proven to be active against synthetic analogs of the stem III and loop C in the two types of 5S rRNAs. In contrast we did not observe any ribozyme‐catalysed hydrolysis within the loop C of the native 5S rRNAs. We considered two possible explanations of the results: an involvement of the loop C in long range interactions and lack of a structural flexibility to form proper tertiary structure of the complex with the ribozyme. From our data it seems that the single stranded nucleotides within the loop C can not form correct RNA duplex structure required for ribozyme activity. It is clear that hammerhead ribozymes can be used for inhibition of different steps of expression of genetic information only if the target sequence occurs in appropriate context, that allows to form correct secondary and tertiary structure of the ribozyme‐substrate complex.