bluuebunny/crossref_metadata_2025_split huggingface dataset:
SUBSTANCE ABUSE AND ACUTE HOSPITAL ADMISSION
Authors: O'Neill Pat 
Published: July 2007

AbstractOne hundred acute admissions to Armidale Hospital were questioned carefully about their use of various substances with a potential for addictive misuse. The results confirmed that acute hospital admission correlates with a higher than average rate of substance abuse. The relationship with alcohol abuse was particularly strong. One‐third of all females and one‐half of all males surveyed were regularly using alcohol at risk levels.
Regulation of Muscle Blood Flow in Obesity
Authors: Hodnett Benjamin L. , Hester Robert L. 
Published: July 2007

ABSTRACTObesity has been shown to impair muscle blood flow in humans. Vasodilatory control mechanisms such as metabolic control, myogenic mechanisms, conducted vasodilation, and release of endothelium‐derived factors may be impaired in obesity due to insulin resistance, hyperglycemia, dyslipidemia, inflammation, oxidative stress, and endothelial dysfunction. The physiological importance of these blood flow control mechanisms has predominately been determined during the increase in blood flow (functional hyperemia) that occurs in response to the increased metabolism associated with exercise. This review examines the mechanisms by which functional hyperemia may be impaired in obesity and indicates areas where further studies are needed. The most extensively studied area of obesity‐induced changes in muscle blood flow has been the role of endothelium‐derived mediators during resting blood flow and exercise‐induced hyperemia. Elevations in oxidative stress alter endothelium‐derived factors, resulting in impaired vasodilatory responses. Alterations in metabolic and conducted vasodilatory regulation of blood flow have not been extensively studied in obesity, providing a potential area of research.
Microvascular Permeability in Diabetes and Insulin Resistance
Authors: Yuan Sarah Y. , Breslin Jerome W. , Perrin Rachel , Gaudreault Nathalie , Guo Mingzhang , Kargozaran Hamed , Wu Mack H. 
Published: July 2007

ABSTRACTMicrovascular barrier injury has been implicated in the initiation and progress of end organ complications of diabetic mellitus. Plasma leakage and fluid retention are seen in various tissues of diabetic patients or animals at the early stages of the disease before structural microangiopathy can be detected. Clinical and experimental evidence suggests that hyperglycemia, often accompanied with insulin deficiency or insulin resistance, causes impaired autoregulation and increased permeability in microvessels. Multiple molecular pathways have been identified as contributors to the altered fluid homeostasis, including increased polyol flux that promotes oxidative stress, advanced glycation that leads to carbonyl stress, and excessive glucose metabolism that results in protein kinase C activation. These abnormal metabolic activities are associated with the production of pro‐inflammatory cytokines and growth factors, which can stimulate an array of signaling reactions and structural changes at the endothelial barrier and ultimately cause microvascular leakage. Interventions that manipulate these metabolic and inflammatory pathways have demonstrated efficacy in delaying the progress of diabetic microvascular complications; however, their direct effects and mechanisms of action on the microcirculation remain elusive. A deeper understanding of the molecular basis of diabetes‐induced endothelial barrier dysfunction will provide a framework for the development of new therapeutic targets to treat this chronic and debilitating disease process.
An optical biosensor study of the interaction parameters and role of hydrophobic tails of cytochrome P450 2B4, b5 and NADPH‐flavoprotein in complex formation
Authors: Ivanov Yuriy D. , Kanaeva Irina P. , Eldarov Michail A. , Sklyabin Konstantin G. , Lehnerer Michael , Schulze Johannes , Hlavica Peter , Archakov Alexander I. 
Published: July 2007

AbstractThe real‐time interactions of membrane proteins ‐ cytochrome P450 2B4, NADPH cytochrome P450 reductase and cytochrome b5 ‐ were studied by use of an optical biosensor system. The association and dissociation rate constants for the individual complexes were measured and the affinities of the redox partners for each other were estimated. The association rate constants of these complexes were found to be close to the diffusion limit and their dissociation rate constants were in the order of 1s‐1. A dominant role of the interaction of the membraneous hydrophobic fragments in the formation of productive electron transferring complexes between the proteins was demonstrated.
Mapping the common antigenic determinants in avidin and streptavidin
Authors: Subramanian N. , Adiga P. Radhakantha 
Published: July 2007

AbstractAn epitope scan analysis of the whole sequence of avidin and core streptavidin using polyclonal antibodies to these two antigens reveal the presence of multiple common epitopes in both the proteins. These antigenic determinants consist mostly of either identical or similar residues. The antibody recognition sites in both antigens are shown to be localized to homologous regions.
Effects of the local anesthetic bupivacaine on mitochondrial energy metabolism: change from uncoupling to decoupling depending on the respiration state
Authors: Sztark François , Ouhabi Rachid , Dabadie Philippe , Mazat Jean‐Pierre 
Published: July 2007

AbstractThe local anesthetic bupivacaine has been found to uncouple oxidative phosphorylation. However, the precise mechanisms of bupivacaine uncoupling have not been elucidated. In the present paper, we demonstrate that the uncoupling effect of the local anesthetic depends on the respiration state. In state 4‐respiration (no ADP phosphorylation), bupivacaine acts as a true protonophoretic uncoupler. On the other hand, in state 3‐respiration (ADP phosphorylation), bupivacaine induces a change in proton pump stoichiometry and appears to be a decoupler (slip inducer). Moreover, at high concentration, the local anesthetic inhibits the respiratory chain itself. Thus, the divergent reports in the literature on the action of bupivacaine show in fact the various mechanisms by which the local anesthetic may alter mitochondrial energy metabolism
Kinetic analysis of the Fenton reaction by ESR‐spin trapping
Authors: Mizuta Yukio , Masumizu Toshiki , Kohno Masahiro , Mori Akitane , Packer Lester 
Published: July 2007

AbstractA quantitative analysis of hydroxyl radical (·OH) generated in the Fe2+‐hydrogen peroxide reaction system was explored by a spin‐trapping method using 5,5‐dimethyl‐1‐pyrroline‐N‐oxide (DMPO) combined with electron spin resonance spectroscopy. Based on the numerical analysis of Fenton‐related reactions, the reduction of DMPO‐OH adduct from 1…n1 stoichiometry prominent at high concentrations of Fe2+ was consistent with a reaction model in which a molar amount of hydrogen peroxide was reduced by two molar amounts of Fe2+. Furthermore, time‐dependent decrease in DMPO‐OH quantity, apparent at much higher concentration of Fe2+, was proved due to the reaction not with Fe2+ but with Fe3+.
Activation of red blood cell glutathione peroxidase and morphological transformation of erythrocytes under the action of tert‐butyl hydroperoxide
Authors: Zavodnik Lev B. , Zavodnik Ilya B. , Niekurzak Andrzej , Szosland Konrad , Bryszewska Maria 
Published: July 2007

AbstractSusceptibility of control and diabetic erythrocytes to oxidative stress was measured after incubation with various concentration of tert‐butyl hydroperoxide (t‐BHP). TBA‐reactive substances (TBARS) formed were determined by the method of Stocks & Dormady [9] modified by Jain [2]. GSH and total glutathione were estimated by the procedure of Ellman [10] and Akerboom and Sies [11]. Activity of GSH peroxidase was determined by the method of Martinez et al. [12]. Protein SH groups were determined after membrane isolation by the method of Dodge et al. [13]. Cell morphology was viewed under phase contrast microscope with a magnification of 500x.All results were analyzed by the unpaired two tailed Student's t‐test. Oxidative treatment of erythrocytes with tert‐butyl hydroperoxide significantly increases the reaction rate but decreases the affinity for substrate (tert‐butyl hydroperoxide). The susceptibility of the enzyme from diabetic erythrocytes to oxidation is higher in comparison with normal cells. The oxidation of cellular reduced glutathione (GSH) is not correlated with oxidation of membranous protein SH‐groups. Oxidative damage of erythrocytes induces significant cell morphological transformations.
Dietary flavonoids and interaction with endogenous antioxidants
Authors: Pietta Piergiorgio , Simonetti Paolo 
Published: July 2007

AbstractGreen tea catechins were given to healthy volunteers under controlled diet for 4 consecutive weeks. Plasma concentrations of ascorbate, urate, α‐tocopherol, β‐carotene and blood levels of total glutathione were measured before, after the supplementation and the washout period. RBC membranes were assayed for their levels of α‐tocopherol and phosphatidylcholine PUFA's. Catechin intake provides antioxidant protection in vivo through a cascade involving endogenous antioxidants, which interact differently according to their redox potentials and polarity. As a final beneficial effect, liposoluble vitamin E and β‐carotene are spared by catechins, resulting in an overall protection against oxidative modification of RBC membrane PUFA's.
Molecular cloning and expression of mouse ceramide glucosyltransferase
Authors: Ichikawa Shinichi , Ozawa Katsuya , Hirabayashi Yoshio 
Published: July 2007

AbstractCeramide glucosyltransferase (EC 2.4.1.80) catalyzcs the first glycosylation step of glycosphingolipid (GSL) synthesis, the transfer of glucose from UDP‐Glucose to hydrophobic ceramide and generate gtucosylceramide (GlcCer). We have chined mouse ceramide glucosyltransferase cDNA from a brain cDNA library by PCR based homology cloning. The nucleotide sequence determination revealed that mouse ceramidc glucosyltransferase cDNA encodes 394 amino acids with a calculated molecular mass of 45 kDa. The amino acid sequence of mouse ceramide glucosyltransferase showed 98% identity with the human sequence. Homology searches against currently available databases identified three homologous proteins in Caenorhabditis elegans and one homologous protein in Cyanobacteria. Highly conserved sequences of ceramide glucosyltransferases and the homologs among a wide variety of organisms suggest biological significance of the lipid glucosylation system.
Gene transfer via pollen‐tube pathway for anti‐fusarium wilt in watermelon
Authors: Chen Wen‐Shaw , Chiu Chien‐Chih , Liu Ho‐Yih , Lee Tan‐Lon , Cheng Jiin‐Tsuey , Lin Cheng‐Chung , Wu Yue‐Jean , Chang Huei‐Yu 
Published: July 2007

AbstractIn order to obtain transgenic fusarium wilt resistant watermelon plants, squash DNA was introduced into the ovaries of watermelon plants via the pollen‐tube pathway. The introduction of foreign genes into ovaries was accomplished using co‐transformation with the CaMV35S‐GUS as a marker. Transformed watermelon plants contained integrated copies of the GUS activity and the seeds of transformed progeny produced a blue color when stained with 5‐bromo‐4‐chloro‐3‐indolyl glucuronide, whereas seeds from untransformed control plants did not. Of 200 transformed seedlings, ten were wilt resistant. The presence of the GUS activity in the genome of stable transgenic seedlings was confirmed by Southern blot analysis. Furthermore, the generation of random amplified polymorphic DNA (RAPD) fingerprints using primers with embedded restriction sites showed amplification products unique to these transgenic plants. Primers OPA‐1 and OPA‐9 gave distinct band patterns of genomic DNA using the polymerase chain reaction.
Influence of a melatonin implant on the free radical load in avian thydroid and its relation with thyroid hormonogenesis
Authors: Prakash Prem , Laloraya Malini , Pradeep Kumar G. 
Published: July 2007

AbstractThe primary aim of this study was to evaluate the effect of melatonin on the oxyradical load in avian thyroid. The superoxide free radicals have been spin trapped by EPR spectroscopy in the thyroid gland of Indian rock pigeon Columba livia following melatonin implantation for two weeks. Melatonin implantation resulted in augmentation in the levels of superoxde radical in the thyroid gland of pigeons with a concomitant decrease in the levels of the total superoxide dismutase activity. This was also associated with increased lipid peroxidation. Melatonin implantation caused a significant increase in plasma levels of glucose. Plasma levels of thyroxine (T4) and triiodothyronine (T3) were lower in the melatonin‐treated pigeons. However, the T3/T4 ratio was higher following melatonin implantation. Since iodination of tyrosine is an H2O2‐dependent phenomenon, the inhibition in the activity of SOD could lead to impaired thyroid hormone synthesis.
Purification and characterization of trichomaglin ‐ A novel ribosome‐inactivating protein with abortifacient activity
Authors: Chen Rong , Xu Yong‐zhen , Wu Jian , Pu Zheng , Jin Shan‐wei , Liu Wang‐yi , Xia Zong‐xiang 
Published: July 2007

AbstractTrichomaglin, a novel ribosome‐inactivating protein, has been isolated from root tuber of a plant Maganlin (Trichosanthes Lepiniate, Cucurbitaceae). The isolation and purification procedure included ammonium sulfate precipitation, Sephadex G‐75 chromatography and CM‐Sephadex C‐50 chromatography. The protein was identified to be homogeneous by SDS‐PAGE and FPLC analysis. Its molecular weight is 24,673 dalton and isoelectric point is 5.8, determined by electrospray ionization mass spectroscopy and isoelectric focusing gel electrophoresis respectively. Trichomaglin can inhibit protein synthesis in rabbit reticulocyte lysate with ID50 of 10.1 nM. When rat ribosome was incubated with trichomaglin, a diagnostic RNA fragment appeared on polyacrylamide gel after ribosomal RNAs were treated with acidic aniline. It was concluded that trichomaglin is an RNA N‐glycosidase. In addition, it has been verified to be an abortifacient protein.
Aldosterone directly induces Na, K‐ATPase α1‐subunit mRNA in the renal cortex of rat
Authors: Seok Jeong‐Ho , Hong Jang‐Hee , Jeon Jong‐Rye , Hur Gang‐Min , Sung Ji‐Yeon , Lee Jae‐Heun 
Published: July 2007

AbstractThe change of blood pressure and the induction of Na, K‐ATPase α1‐subunit mRNA have been investigated in the renal cortex of aldosterone‐treated hypertensive rat. The increase of blood pressure by aldosterone‐treatment for 25 days was decreased by the treatment of amiloride or spironolactone. The level of Na, K‐ATPase α1‐subunit mRNA of the renal cortex in aldosterone‐treated rat was increased than that in the control, and its increase was repressed by treatment of spironolactone, but not altered by the treatment of amiloride. This result suggests that the increase of Na, K‐ATPase α1‐subunit mRNA in the renal cortex of aldosterone‐treated hypertensive rat may be related with the direct induction of Na, K‐ATPase mRNA without the increase of Na‐traffic through Na‐channel.
Preparation and characterization of β1‐bungarotoxin bispecific monoclonal antibody
Authors: Yang C. C. , Chan H. L. 
Published: July 2007

AbstractA hybrid hybridoma (tetradoma) that produces bispecific monoclonal antibodies (mAbs)2, which recognize two different epitopes on the A chain of β1‐bungarotoxin (β1‐bgt) at peptide sequences 46‐51 and 100‐106, has been obtained by fusing two hybridoma cell lines. The bispecific mAb were observed to inhibit 98% of the enzymatic activity of β1‐bgt and neutralize its lethal toxicity completely. The avidity between the bispecific mAb and β1‐bgt was noted to be 4.5×1010 (liter/nmol), which is about 45‐150 folds higher than the avidity of its two parental mAbs. All the soluble complexes, obtained from bispecific mAb and β1‐bgt with different molar ratios, emerged in the void volume of size exclusion chromatography column, indicating multiple complexes of β1‐bgt and bispecific mAb were formed. Based on these results, it indicated that the binding of bispecific mAb with its two epitopes on β1‐bgt, which facilitates the immuno‐complex formation and enhances the avidity, also highly neutralizes the biological activity of β1‐bgt.
Site‐Directed Mutagenesis of Asp313, Glu315, and Asp391 Residues in Chitinase of Aeromonas Caviae
Authors: Lin Fu‐Pang , Chen Hsing‐Chen , Lin Chung‐Saint 
Published: July 2007

AbstractSite‐directed mutagenesis was used to explore the roles of amino acid residues involved in the activity of chitinase from Aeromonas caviae .Kinetic parameters for 4‐methylumbelliferyl‐N, N‐diacetylchitobiose or 4‐methylumbelliferyl‐N,N, N‐triacetylchitotriose hydrolysis were determined with wild‐type and mutant chitinases. Chitinases with the mutations E315D (or Q) and D391E (or N) were severely impaired and had dramatically decreased kcat. However, the effect of the these mutations on the K m values were different. The function ofthe carboxylgroup of Asp313 was partially replaced by the amide ofAsn when the 4‐methylumbelliferyl‐N, N, N‐triacetylchitotriose substrate was used. Results indicated that Asp313, Glu315, and Asp391 might be the best candidates for the catalytic residues of chitinase A from Aeromonas caviae.
Isolation and Characterization of a Mutant Defective in the Production of Methanol Dehydrogenase from a New Restricted Facultative Methanol‐Oxidizing Bacterium
Authors: Kang Jin Kwon , Kim Si Wouk , Jeong Hye Gwang , Park Jong Kun , Park Yeal , Lee Jung Sup 
Published: July 2007

AbstractA new restricted facultative methanol‐oxidizing bacterium Methylobacillus sp. strain SK1 (DSM 8269) was subjected to insertion mutagenesis studies with the transposon Tn5 to generate mutants deficient in the production of methanol dehydrogenase (MDH).The transposon was conjugally transferred into the methylotroph by using the triparental mating procedure. The mutants induced by Tn5 were selected directly from a plate containing succinate by using the allyl alcohol selection procedure. The transposition of Tn5 to the bacterium showed a moderate transposition frequency (10‐5‐10‐6).Southern hybridization analysis confirmed that the transposon Tn5 was inserted into the chromosomal DNA of the mutants. In addition, the mutants had no RNA transcripts produced from the mdh gene, as judged by Northern blot analysis. The mutants could neither grow on methanol nor produce MDH protein, as determined by Western blotanalysis with anti‐MDH antibody. These results suggest that Tn5 mutagenesis maybe a useful tool for the molecular analysis of a facultative methanol‐oxidizing bacterium.
5′‐Upstream Structure of the Gene Coding for Chicken Riboflavin‐Binding Protein and Its Relation to Estrogen Induction
Authors: Hamajima Susumu , Hirano Hiroko , Horiuchi Saburo , Ono Shigeru 
Published: July 2007

AbstractTo elucidate the mechanism of the estrogen‐dependent induction of chicken riboflavin‐binding protein (RfBP), we analyzed the 5′‐upstream structure of its gene. A noncoding exon exists there, and around this sequence, 9 widely spaced half‐palindromic estrogen‐response element (ERE) motifs (5‐GGTCA or 5‐TGACC) were found. Furthermore, an imperfect ERE‐like palindromic sequence (5′‐ATGTCANNNTGACAT‐3) was also found at the 2.25 kb upstream region. No consensus palindromic ERE was observed. By luciferase reporter assay, the regions containing the half ERE motifs and the imperfect ERE showed estrogen‐dependent enhancer activities, suggesting that these two characteristic sequences might confer estrogen‐inducibility upon the chicken RfBP gene. However the activities were lower than that of a consensus ERE. It remains uncertain whether these sequences act cooperatively.
Characterization of Cytostatically Active Glycosphingolipids Isolated from Thioglycollate‐Elicited Murine Macrophages
Authors: Schaade Lars , Ritter Klaus , Schiebel Hans‐Martin , Thomssen Reiner , Kleines Michael 
Published: July 2007

AbstractTwo acidic glycosphingolipids (gangliosides) derived from mouse macrophage membranes and separated by thin‐layer chromatography have a strong cytostatic effect on human and mouse tumor cells. The structure of the two gangliosides, named MphiG1 and MphiG2, was elucidated by application of physicochemical and immunochemical methods. Gas chromatography and mass spectrometry of MphiG1 and MphiG2 classified them as isomeric monosialogangliosides with ceramide moieties composed of sphingosine as the long‐chain base, C16 and C18 fatty acids, respectively, and a lacto‐tetraose backbone. For MphiG1, additional immunochemical findings led to the proposed structure IV3NeuAc‐nLcOse4Cer. The immunochemical reactions of MphiG2 suggest a branched structure for the oligosaccharide moiety.
Immunochemical Determination of Cellular Content of Translation Release Factor RF4 in Escherichia coli
Authors: Andersen Lars Dyrskjot , Moreno Juan Manuel Palacios , Clark Brian F. C. , Mortensen Kim Kusk , Sperling‐Petersen Hans Uffe 
Published: July 2007

AbstractThe biosynthesis of proteins in prokaryotes is terminated when a stop codon is present in the A‐site of the 70S ribosomal complex. Four different translation termination factors are known to participate in the termination process. Release factor RF1 and RF2 are responsible for the recognition of the stop codons, and RF3 is known to accelerate the overall termination process. Release factor RF4 is a protein involved in the release of the mRNA and tRNA from the ribosomal complex. Furthermore, RF4 is involved in the proofreading in the elongation step of protein biosynthesis. The cellular contents of RF1, RF2, and RF3 were determined earlier. Here we report the cellular content of RF4 in Escherichia coli to be ∼16 500 molecules per cell. The cells were grown in a rich medium and harvested in the beginning of the exponential growth phase. The quantifications were performed by using Western immunoblotting with radioactive iodinated streptavidin and biotinylated rabbit anti‐mouse immunoglobulins plus a highly specific monoclonal antibody against RF4 as first antibody.
Rearrangement in the Coding and 5′ Region of P53 Gene in Human Oral Tumors
Authors: Patnaik S. , Nayak B. K. , Das B. R. 
Published: July 2007

AbstractDifferent postreplicative, transcriptional, and translational mechanisms responsible for p53 gene inactivation are slowly unfolding. Rearrangement of the p53 gene is a very rare event in human solid tumors and has been reported only in osteosarcomas. From our laboratory we have recently reported rearrangement only in the coding region of the p53 gene in breast tumors. In this report we have undertaken a systemic investigation of p53 in oral tumors. Results have shown rearrangement in the coding region of p53 in 20% of cases and in the 5′ region of p53 gene in 8% of cases. No allelic loss and amplification of p53 gene was observed in these tumor samples. In our earlier studies on breast tumors, we found no abnormality in the 5′ region of p53. However, in the present study we report for the first time rearrangement in the 5′ region of p53 in oral tumors. Correlation of p53 gene rearrangement with p53 expression of RNA and protein indicates that rearrangement in the 5′ region of p53 might not have a role in p53 expression. However, rearrangement in the coding region of p53 might play a critical role in controlling p53 gene activity in the process of tumorigenesis.
Cloning and Characterization of the Non‐Catalytic Heavy Chain of Mouse Complement Factor I Gene: Structure Comparison with the Human Homologue
Authors: Yun Young‐Sup , Goldberger Gabriel , Minta Joe O. 
Published: July 2007

AbstractThe above listed article appeared in issue 47(3), pages 493‐500, of Biochemistry and Molecular Biology International. Taylor & Francis regrets that in the original publication, a large portion of text was omitted from the article's Introduction. The following text represents the correct version of this article's Introduction.