Journal of free radicals in biology & medicine最新文献

{"title":"Methods in enzymology volume 105, oxygen radicals in biological systems","authors":"Kelvin J.A. Davies Ph.D.","doi":"10.1016/0748-5514(85)90125-4","DOIUrl":"10.1016/0748-5514(85)90125-4","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 3","pages":"Page 240"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90125-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"108129024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Announcements and calendar","authors":"","doi":"10.1016/0748-5514(85)90022-4","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90022-4","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 2","pages":"Page 169"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90022-4","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91651486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In vitro antioxidant properties of potential biotransformaton products of salicylate, sulphasalazine and aminodypyrine","authors":"W.H. Betts ,&nbsp;M.W. Whitehouse ,&nbsp;L.G. Cleland ,&nbsp;B. Vernon-Roberts","doi":"10.1016/0748-5514(85)90131-X","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90131-X","url":null,"abstract":"<div><p>2,3- and 2,5-dihydroxybenzonate (formed from salicylate by nonenzymatic or enzymatic hydroxylation), and 5-aminosalicylate (a prime metabolite of sulphasalazine) are highly effecient quenchers of the chemiluminescence (CL) produced by an oxyl radical flux. Monohydric phenols (including salicylate) and <em>meta</em>-dihydric phenols are virtually inactive. These findings suggest that the <em>para</em>- o3 <em>ortho</em>-configuration of hydroxy/amino groups is important for this activity. These differences in activity between 2,3- and 2,5-dihydroxybenzonate, 5-aminosaalicylate and monohydric phenols/2,4-, 2,6-dihydroxybenzoate were not seen in assays monitoring hydroxyl radicals. 4-aminophenazone (an oxidation product of both amidopyrine/aminopyrine and isopyrine), 4-hydroxyphenazone and some dietary catechols (and ascorbate), are also potent quenchers of oxy radical-associated CL.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 4","pages":"Pages 273-280"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90131-X","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72241743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Announcements and calendar","authors":"","doi":"10.1016/0748-5514(85)90143-6","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90143-6","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 4","pages":"Pages 335-336"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90143-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136549182","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Free radicals in biology and medicine","authors":"Barry Halliwell,&nbsp;John M.C. Gutteridge","doi":"10.1016/0748-5514(85)90140-0","DOIUrl":"https://doi.org/10.1016/0748-5514(85)90140-0","url":null,"abstract":"","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 4","pages":"Pages 331-332"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90140-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136549184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Oxygen toxicity: Loss of lung macrophage function without metabolite depletion","authors":"Mark W. Sutherland ,&nbsp;Mitchell Glass ,&nbsp;June Nelson ,&nbsp;Yuen Lyen ,&nbsp;Henry Jay Forman","doi":"10.1016/0748-5514(85)90120-5","DOIUrl":"10.1016/0748-5514(85)90120-5","url":null,"abstract":"<div><p>Hyperoxia inhibited concanavalin A stimulated O⁻₂ release (respiratory burst) of alveolar macrophages obtained by bronchoalveolar lavage from rats. After 36 h of normobaric 100% O₂, a partial reversal (48%) of the inhibition was produced by addition of glucose. Since oxidant-induced, reversible NADPH depletion correlates with reversible inhibition of the respiratory burst, intracellular NADPH was assayed to determine whether irreversible inhibition of the respiratory burst was related to persistent changes in this metabolite. The cellular concentrations of ATP, glutathione, and ascorbate were also measured. After 36 h of hyperoxia, NADPH concentration in alveolar macrophages rose slightly while ATP and glutathione content remained at control levels. Ascorbate levels fell significantly but were not responsible for respiratory burst inhibition. Thus, irreversible loss of cellular function in hyperoxia is not due to persistent alterations in these metabolites. Significant amounts of both glutathione and ascorbate were found in extracellular of lung washings, indicating high concentrations in the aqueous subphase in the lung fluid lining. There was no change in total content of these extracellular antioxidants following O₂ exposure.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 3","pages":"Pages 209-214"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90120-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14146556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ethylene production from α-keto-4-thiomethylbutyric acid by isolated rat liver cells, suspension medium, and perfusates in the absence and presence of iron","authors":"Dennis E. Feierman,&nbsp;Arthur I. Cederbaum","doi":"10.1016/0748-5514(85)90020-0","DOIUrl":"10.1016/0748-5514(85)90020-0","url":null,"abstract":"<div><p>Experiments were carried out to evaluate the production of hydroxyl radical-like species by intact rat liver cells by assaying for the production of ethylene from α-keto-4-thiomethylbutyric acid in the absence and presence of added iron. In the absence of iron, a low rate of ethylene production, which was not sensitive to superoxide dismutase, catalase, or competitive scavengers was observed. Ethylene was produced when KMBA was incubated with perfusates of rat liver or the suspension medium obtained after incubating liver cells for varying periods of time, followed by removal of the liver cells. Boiling the perfusate or suspension medium had no effect on ethylene production. This ethylene production does not appear to reflect an oxygen radical-mediated event. The addition of ferric-EDTA, but not ferric-desferrioxamine, increased ethylene production by the hepatocyte suspensions in a reaction sensitive to inhibition by catalase, ascorbate oxidase, and competitive scavengers, but not superoxide dismutase. The sensitivity to externally added catalase and ascorbate oxidase suggested that the ethylene production reflected an extracellular oxygen radical generating system. Ferric alone and several ferric chelates, for example, ferric-ATP, ADP, AMP, histidine, and citrate stimulated ethylene production using perfusates of liver or suspension medium after removal of the hepatocytes. The sensitivity of the added iron system to ascorbate oxidase suggested that during perfusion or incubation of liver cells, efflux of ascorbate occurs, follwed by reduction of the iron and subsequently, extracellular production of oxygen radicals. Indeed, a strong correlation was observed between rates of ethylene production in the presence of iron and levels of ascorbate in the perfusates. Thus, the use of KMBA plus iron is not suitable to detect intracellular production of hydroxyl radical-like species in cells such as hepatocytes, which leak ascorbate.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 2","pages":"Pages 155-162"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90020-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14146655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficiency of chelated iron compounds as catalysts for the Haber-Weiss reaction","authors":"Harry C. Sutton","doi":"10.1016/0748-5514(85)90118-7","DOIUrl":"10.1016/0748-5514(85)90118-7","url":null,"abstract":"<div><p>The oxidation of formate to CO₂ has been used to quantify ·OH yields produced in oxygenated solutions by chelated iron salts reacting either directly with H₂O₂ in the Fenton reaction, or as catalysts in the Haber-Weiss reaction between H₂O₂ and radiolytically generated superoxide. This system involves a chain sequence since ·OH regenerates <span><math><mtext>O</mtext><msup><mi></mi><mn>⨪</mn></msup><msub><mi></mi><mn>2</mn></msub></math></span> when producing CO₂. Kinetic studies have been employed to show that catalysis by FE-EDTA occurs by reduction of Fe³⁺-EDTA by <span><math><mtext>O</mtext><msup><mi></mi><mn>⨪</mn></msup><msub><mi></mi><mn>2</mn></msub></math></span>. followed by its reaoxidation by H₂O₂, and to show how <span><math><mtext>O</mtext><msup><mi></mi><mn>⨪</mn></msup><msub><mi></mi><mn>2</mn></msub></math></span> is ultimately consumed. At pH 7.3 more than 50 ·OH radicals can be produced per molecule of Fe-EDTA and CO₂ yields can exceed five per molecule of radiolytically generated <span><math><mtext>O</mtext><msup><mi></mi><mn>⨪</mn></msup><msub><mi></mi><mn>2</mn></msub></math></span>. Iron chelated with pyrophosphate, DTPA, citrate, ATP or ADP in phosphate or Tris buffer at pH 7.3 has less than 7% of the catalytic ability of Fe-EDTA (considerably less in most cases) even though all these ferrous chelates give appreciable yields of ·OH in the Fenton reaction. Unchelated iron has no catalytic ability. Catalysis of the Haber-Weiss reaction in homogenous solution by iron salts, either free or chelated with nucleotides or citrate, is evidently a very inefficient process, and its possible role in superoxide toxicity must be viewed with these reservations.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 3","pages":"Pages 195-202"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90118-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14146656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Conservation of vitamin C by uric acid in blood","authors":"Alex Sevanian ,&nbsp;Kelvin J.A. Davies ,&nbsp;Paul Hochstein","doi":"10.1016/0748-5514(85)90015-7","DOIUrl":"10.1016/0748-5514(85)90015-7","url":null,"abstract":"<div><p>Urate at physiological concentrations increased the stability of ascorbate in human serum approximately fivefold. These measurements were made by depleting human serum of urate with uricase. In model experiments (using phosphate buffer instead of serum), urate protected against iron-induced ascorbate oxidation and, to a lesser extent, pH-induced ascorbate oxidation. In both human serum and in phosphate buffer, urate exerted its protective effect without itself undergoing measurable oxidation as determined by spectrophotometric and high pressure liquid chromatography (HPLC) techniques. These experiments suggest an important physiological role for urate in preserving ascorbate in blood and other biological fluids.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 2","pages":"Pages 117-124"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90015-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14951594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gas chromatography-mass spectrometry method for determination of phospholipid peroxides; II. Transesterification to form pentafluorobenzyl esters and detection with picogram sensitivity","authors":"Frederik J.G.M. van Kuijk ,&nbsp;David W. Thomas ,&nbsp;Robert J. Stephens ,&nbsp;Edward A. Dratz","doi":"10.1016/0748-5514(85)90151-5","DOIUrl":"10.1016/0748-5514(85)90151-5","url":null,"abstract":"<div><p>The purpose of this study is to develop a higher sensitivity method to detect phospholipid peroxides in tissues to more effectively investigate the role of lipid peroxidation in pathology. We recently presented a gas chromatography-mass spectrometry (GC-MS) method for identification and measurement of phospholipid peroxides at the 10 ng level (van Kuijk, et al. <em>J. Free Rad. Biol. Med.</em>, <strong>1</strong>: 215–225, 1985) based on transesterification to form fatty acid methyl ester derivatives. While this method is quite usefule under some circumstances, more sensitivity was desirable to analyse trace amounts of lipid peroxidation products in small samples of various tissues. We present a method to prepare pentalfluorobenzyl esters of fatty acids and hydroxy fatty acids directly from phospholipids by transesterification at room temperature or from triglycerides at 60%C. Oxidized lipids are extracted into dichloromethane and peroxide functions are reduced with sodium borohydride. Transesterification of phospholipids is carried out in dichloromethane with 20% (v/v) pentafluorobenzyl alcohol, 1% (w/v) potassium tertbutoxide and 0.2 N (m-trifluoromethyl phenyl) trimethyl ammonium hydroxide at room temperature for 30 min. Pentafluorobenzyl esters are purified on open silica columns. O-trimethyl silyl derivatives of the alcohol functions are formed, and GC-MS is carried out with negative ion chemical ionization detection. The single or double oxidation products of oleate, linoleate, arachidonate, and docosahexaenoate were detected with 10 pg sensitivity in oxidized rat retina phospholipids or synthetic phospholipids by negative ion chemical ionization with specific ion monitoring of carboxylate anions.</p></div>","PeriodicalId":77737,"journal":{"name":"Journal of free radicals in biology & medicine","volume":"1 5","pages":"Pages 387-393"},"PeriodicalIF":0.0,"publicationDate":"1985-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0748-5514(85)90151-5","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"14955086","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}