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Aalt Bast - One of the best experts on this subject based on the ideXlab platform.
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feruliC aCid from aleurone determines the antioxidant potenCy of wheat grain tritiCum aestivum l
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Nuria Mateo Anson, Aalt Bast, Robin Van Den Berg, Rob Havenaar, Guido R M M HaenenAbstract:Grain is an important sourCe of phytoChemiCals, whiCh have potent antioxidant CapaCity. They have been impliCated in the benefiCial health effeCt of whole grains in reduCing CardiovasCular disease and type 2 diabetes. The aim of the present study was to identify the most important antioxidant fraCtions of wheat grain. It was found that the aleurone Content of these fraCtions was highly Correlated with the antioxidant CapaCity of the fraCtions (r = 0.96, p < 0.0001). FeruliC aCid appeared to be the major Contributor to the antioxidant CapaCity in fraCtions with higher antioxidant CapaCity. The Contribution of protein was rather limited. It was ConCluded that the antioxidant potenCy of wheat grain fraCtions is predominantly determined by aleurone Content, whiCh Can be attributed to the presenCe of relatively large amounts of phenoliC Compounds, primarily feruliC aCid. © 2008 AmeriCan ChemiCal SoCiety. ChemiCals / CAS: CoumariC aCid, 25429-38-3; feruliC aCid, 1135-24-6, 24276-84-4; Trolox C, 56305-04-5; 6-hydroxy-2,5,7,8-tetramethylChroman-2-CarboxyliC aCid, 56305-04-5; Antioxidants; Chromans; CoumariC ACids; feruliC aCid, 1135-24-6; Plant ExtraCts
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appliCability of an improved Trolox equivalent antioxidant CapaCity teaC assay for evaluation of antioxidant CapaCity measurements of mixtures
Food Chemistry, 1999Co-Authors: R Van Den Berg, Guido R M M Haenen, H Van Den Berg, Aalt BastAbstract:The TEAC (Trolox equivalent antioxidant CapaCity) assay is based on sCavenging of 2,2'-azinobis-(3- ethylbenzothiazoline-6-sulfonate) radiCal anions (ABTS(.-)). In this report we desCribe a modifiCation based on pre-generation of the ABTS radiCal anions with a thermolabile azo Compound, 2,2'-azobis- (2-amidinopropane)HCl (ABAP). This modifiCation makes the assay less susCeptible to artefaCts, e.g. influenCe on the radiCal generation proCess. For most antioxidants tested, a biphasiC reaCtion pattern was seen, i.e. a fast and slow sCavenging rate. We evaluated appliCation of the assay with both lipophiliC and hydrophiliC Compounds with antioxidant CapaCity. Several organiC solvents, Compatible with water, were tested with α-toCopherol, querCetin and β-Carotene. It was found that the TEACs differed in various solvents. Under standardized Conditions additivity of TEACs obtained from individual antioxidants Could be demonstrated. This might enable appliCation of the assay for the identifiCation of 'unknown' antioxidants. Copyright (C) 1999 Elsevier SCienCe Ltd. ChemiCals/CAS: 2,2' azobis(2 amidinopropane), 13217-66-8; alpha toCopherol, 1406-18-4, 1406-70-8, 52225-20-4, 58-95-7, 59-02-9; asCorbiC aCid, 134-03-2, 15421-15-5, 50-81-7; aurantiin, 10236-47-2, 12619-61-3, 29658-83-1, 82350-96-7; beta Carotene, 7235-40-7; Cryptoxanthin, 472-70-8; dehydroasCorbiC aCid, 33124-69-5, 490-83-5; hesperidin, 520-26-3; lyCopene, 502-65-8; querCetin, 117-39-5; Trolox C, 56305-04-5; zeaxanthin, 144-68-3
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appliCability of an improved Trolox equivalent antioxidant CapaCity teaC assay for evaluation of antioxidant CapaCity measurements of mixtures
Food Chemistry, 1999Co-Authors: R Van Den Berg, Guido R M M Haenen, H Van Den Berg, Aalt BastAbstract:The TEAC (Trolox equivalent antioxidant CapaCity) assay is based on sCavenging of 2,2'-azinobis-(3- ethylbenzothiazoline-6-sulfonate) radiCal anions (ABTS(.-)). In this report we desCribe a modifiCation based on pre-generation of the ABTS radiCal anions with a thermolabile azo Compound, 2,2'-azobis- (2-amidinopropane)HCl (ABAP). This modifiCation makes the assay less susCeptible to artefaCts, e.g. influenCe on the radiCal generation proCess. For most antioxidants tested, a biphasiC reaCtion pattern was seen, i.e. a fast and slow sCavenging rate. We evaluated appliCation of the assay with both lipophiliC and hydrophiliC Compounds with antioxidant CapaCity. Several organiC solvents, Compatible with water, were tested with α-toCopherol, querCetin and β-Carotene. It was found that the TEACs differed in various solvents. Under standardized Conditions additivity of TEACs obtained from individual antioxidants Could be demonstrated. This might enable appliCation of the assay for the identifiCation of 'unknown' antioxidants. Copyright (C) 1999 Elsevier SCienCe Ltd. ChemiCals/CAS: 2,2' azobis(2 amidinopropane), 13217-66-8; alpha toCopherol, 1406-18-4, 1406-70-8, 52225-20-4, 58-95-7, 59-02-9; asCorbiC aCid, 134-03-2, 15421-15-5, 50-81-7; aurantiin, 10236-47-2, 12619-61-3, 29658-83-1, 82350-96-7; beta Carotene, 7235-40-7; Cryptoxanthin, 472-70-8; dehydroasCorbiC aCid, 33124-69-5, 490-83-5; hesperidin, 520-26-3; lyCopene, 502-65-8; querCetin, 117-39-5; Trolox C, 56305-04-5; zeaxanthin, 144-68-3
Guido R M M Haenen - One of the best experts on this subject based on the ideXlab platform.
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feruliC aCid from aleurone determines the antioxidant potenCy of wheat grain tritiCum aestivum l
Journal of Agricultural and Food Chemistry, 2008Co-Authors: Nuria Mateo Anson, Aalt Bast, Robin Van Den Berg, Rob Havenaar, Guido R M M HaenenAbstract:Grain is an important sourCe of phytoChemiCals, whiCh have potent antioxidant CapaCity. They have been impliCated in the benefiCial health effeCt of whole grains in reduCing CardiovasCular disease and type 2 diabetes. The aim of the present study was to identify the most important antioxidant fraCtions of wheat grain. It was found that the aleurone Content of these fraCtions was highly Correlated with the antioxidant CapaCity of the fraCtions (r = 0.96, p < 0.0001). FeruliC aCid appeared to be the major Contributor to the antioxidant CapaCity in fraCtions with higher antioxidant CapaCity. The Contribution of protein was rather limited. It was ConCluded that the antioxidant potenCy of wheat grain fraCtions is predominantly determined by aleurone Content, whiCh Can be attributed to the presenCe of relatively large amounts of phenoliC Compounds, primarily feruliC aCid. © 2008 AmeriCan ChemiCal SoCiety. ChemiCals / CAS: CoumariC aCid, 25429-38-3; feruliC aCid, 1135-24-6, 24276-84-4; Trolox C, 56305-04-5; 6-hydroxy-2,5,7,8-tetramethylChroman-2-CarboxyliC aCid, 56305-04-5; Antioxidants; Chromans; CoumariC ACids; feruliC aCid, 1135-24-6; Plant ExtraCts
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appliCability of an improved Trolox equivalent antioxidant CapaCity teaC assay for evaluation of antioxidant CapaCity measurements of mixtures
Food Chemistry, 1999Co-Authors: R Van Den Berg, Guido R M M Haenen, H Van Den Berg, Aalt BastAbstract:The TEAC (Trolox equivalent antioxidant CapaCity) assay is based on sCavenging of 2,2'-azinobis-(3- ethylbenzothiazoline-6-sulfonate) radiCal anions (ABTS(.-)). In this report we desCribe a modifiCation based on pre-generation of the ABTS radiCal anions with a thermolabile azo Compound, 2,2'-azobis- (2-amidinopropane)HCl (ABAP). This modifiCation makes the assay less susCeptible to artefaCts, e.g. influenCe on the radiCal generation proCess. For most antioxidants tested, a biphasiC reaCtion pattern was seen, i.e. a fast and slow sCavenging rate. We evaluated appliCation of the assay with both lipophiliC and hydrophiliC Compounds with antioxidant CapaCity. Several organiC solvents, Compatible with water, were tested with α-toCopherol, querCetin and β-Carotene. It was found that the TEACs differed in various solvents. Under standardized Conditions additivity of TEACs obtained from individual antioxidants Could be demonstrated. This might enable appliCation of the assay for the identifiCation of 'unknown' antioxidants. Copyright (C) 1999 Elsevier SCienCe Ltd. ChemiCals/CAS: 2,2' azobis(2 amidinopropane), 13217-66-8; alpha toCopherol, 1406-18-4, 1406-70-8, 52225-20-4, 58-95-7, 59-02-9; asCorbiC aCid, 134-03-2, 15421-15-5, 50-81-7; aurantiin, 10236-47-2, 12619-61-3, 29658-83-1, 82350-96-7; beta Carotene, 7235-40-7; Cryptoxanthin, 472-70-8; dehydroasCorbiC aCid, 33124-69-5, 490-83-5; hesperidin, 520-26-3; lyCopene, 502-65-8; querCetin, 117-39-5; Trolox C, 56305-04-5; zeaxanthin, 144-68-3
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appliCability of an improved Trolox equivalent antioxidant CapaCity teaC assay for evaluation of antioxidant CapaCity measurements of mixtures
Food Chemistry, 1999Co-Authors: R Van Den Berg, Guido R M M Haenen, H Van Den Berg, Aalt BastAbstract:The TEAC (Trolox equivalent antioxidant CapaCity) assay is based on sCavenging of 2,2'-azinobis-(3- ethylbenzothiazoline-6-sulfonate) radiCal anions (ABTS(.-)). In this report we desCribe a modifiCation based on pre-generation of the ABTS radiCal anions with a thermolabile azo Compound, 2,2'-azobis- (2-amidinopropane)HCl (ABAP). This modifiCation makes the assay less susCeptible to artefaCts, e.g. influenCe on the radiCal generation proCess. For most antioxidants tested, a biphasiC reaCtion pattern was seen, i.e. a fast and slow sCavenging rate. We evaluated appliCation of the assay with both lipophiliC and hydrophiliC Compounds with antioxidant CapaCity. Several organiC solvents, Compatible with water, were tested with α-toCopherol, querCetin and β-Carotene. It was found that the TEACs differed in various solvents. Under standardized Conditions additivity of TEACs obtained from individual antioxidants Could be demonstrated. This might enable appliCation of the assay for the identifiCation of 'unknown' antioxidants. Copyright (C) 1999 Elsevier SCienCe Ltd. ChemiCals/CAS: 2,2' azobis(2 amidinopropane), 13217-66-8; alpha toCopherol, 1406-18-4, 1406-70-8, 52225-20-4, 58-95-7, 59-02-9; asCorbiC aCid, 134-03-2, 15421-15-5, 50-81-7; aurantiin, 10236-47-2, 12619-61-3, 29658-83-1, 82350-96-7; beta Carotene, 7235-40-7; Cryptoxanthin, 472-70-8; dehydroasCorbiC aCid, 33124-69-5, 490-83-5; hesperidin, 520-26-3; lyCopene, 502-65-8; querCetin, 117-39-5; Trolox C, 56305-04-5; zeaxanthin, 144-68-3
Gary Williamson - One of the best experts on this subject based on the ideXlab platform.
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antioxidant properties of CateChins and proanthoCyanidins effeCt of polymerisation galloylation and glyCosylation
Free Radical Research, 1998Co-Authors: Geoffrey W Plumb, Véronique Cheynier, Sonia De Pascualteresa, Celestino Santosbuelga, Gary WilliamsonAbstract:A range of CateChins and oligomeriC proCyanidins was purified by high performanCe liquid Chromatography (HPLC) from grape seed, apple skin, lentil and almond flesh. CateChins, galloylated epiCateChin, glyCosylated CateChin, proCyanidin dimers, galloylated dimers, trimer, and tetramer speCies were all identified, purified and quantified by HPLC, LC-MS and NMR. The antioxidant properties of these Compounds were assessed using two methods: (a) inhibition of asCorbate/iron-induCed peroxidation of phosphatidylCholine liposomes; (b) sCavenging of the radiCal Cation of 2,2′-azinobis(3-ethyl-benzothiazoline-6-sulphonate) (ABTS) relative to the water-soluble vitamin E analogue Trolox C (expressed as Trolox C equivalent antioxidant CapaCity, TEAC). Antioxidant aCtivity in the lipid phase deCreased with polymerisation in Contrast with antioxidant aCtion in the aqueous phase whiCh inCreased from monomer to trimer and then deCreased from trimer to tetramer. Galloylation of CateChin and dimeriC proCyanidins deCreased l...
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antioxidant properties of CateChins and proanthoCyanidins effeCt of polymerisation galloylation and glyCosylation
Free Radical Research, 1998Co-Authors: Geoffrey W Plumb, Véronique Cheynier, Sonia De Pascualteresa, Celestino Santosbuelga, Gary WilliamsonAbstract:A range of CateChins and oligomeriC proCyanidins was purified by high performanCe liquid Chromatography (HPLC) from grape seed, apple skin, lentil and almond flesh. CateChins, galloylated epiCateChin, glyCosylated CateChin, proCyanidin dimers, galloylated dimers, trimer, and tetramer speCies were all identified, purified and quantified by HPLC, LC-MS and NMR. The antioxidant properties of these Compounds were assessed using two methods: (a) inhibition of asCorbate/iron-induCed peroxidation of phosphatidylCholine liposomes; (b) sCavenging of the radiCal Cation of 2,2′-azinobis(3-ethyl-benzothiazoline-6-sulphonate) (ABTS) relative to the water-soluble vitamin E analogue Trolox C (expressed as Trolox C equivalent antioxidant CapaCity, TEAC). Antioxidant aCtivity in the lipid phase deCreased with polymerisation in Contrast with antioxidant aCtion in the aqueous phase whiCh inCreased from monomer to trimer and then deCreased from trimer to tetramer. Galloylation of CateChin and dimeriC proCyanidins deCreased l...
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antioxidant properties of the major polyphenoliC Compounds in broCColi
Free Radical Research, 1997Co-Authors: Geoffrey W Plumb, Keith R Price, Michael J C Rhodes, Gary WilliamsonAbstract:We have examined the antioxidant aCtivity of the major phenoliC Compounds in BroCColi: two flavonol glyCosides (querCetin 3–O-sophoroside and kaemp-ferol 3-O-sophoroside) and four hydroxyCinnamiC aCid esters (1,2′-disinapoyl-2-feruloyl gentiobiose, 1-sinapoyl-2-feruloyl gentiobiose, 1,2,2′-trisinapoyl gentiobiose and 1,2-disinapoyl gentiobiose). The Trolox C equivalent antioxidant CapaCity (TEAC) and inhibition of iron/asCorbate-induCed lipid per-oxidation of phosphatidyl Choline vesiCles were measured. In the aqueous phase TEAC assay, the two flavonol glyCosides were less aCtive than their respeCtive aglyCones. TEAC values for the hydroxyCinnamiC aCid esters were less than the sum of their Constituent hydroxyCinnamiC aCids on a molar basis. QuerCetin 3-O-sophoroside was a potent inhibitor of lipid peroxidation, in Contrast to kaempferol 3-O-sophoroside. The hydroxyCinnamiC aCid esters were highly effeCtive at preventing lipid damage with the exCeption of 1,2,2′-trisinapoyl gentiobiose. The six Compounds ...
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dietary querCetin glyCosides antioxidant aCtivity and induCtion of the antiCarCinogeniC phase ii marker enzyme quinone reduCtase in hepalClC7 Cells
Carcinogenesis, 1996Co-Authors: Gary Williamson, Keith R Price, Geoff W Plumb, Yasushi Uda, Michael J C RhodesAbstract:It has reCently been shown by Hollman et al. (Am. J. Clin. Nutr., 62, 1276-1282) that flavonoid glyCosides are preferentially absorbed from dietary onions Compared to the flavonoid aglyCone. In the light of this, we have Compared the bioaCtivities of the two most abundant flavonoid glyCosides that we have purified from onions (querCetin-3,4'-digluCoside and querCetin-4'-gluCoside) to the querCetin aglyCone, and also to the more Commonly studied CommerCially-available flavonoid glyCosides, rutin (querCetin-3-rutinoside) and isoquerCitrin (querCetin-3-gluCoside). QuerCetin aglyCone was the most effeCtive induCer of the antiCarCinogeniC phase II marker enzyme, quinone reduCtase (QR), in mouse HepalClC7 Cells. Of the glyCosides, only querCetin-4'-gluCoside was able to induCe QR aCtivity in this assay. Inhibition of NADPH/iron- and asCorbate/iron-induCed lipid peroxidation of human liver miCrosomes, and the Trolox C-equivalent antioxidant CapaCity (TEAC), were also measured. The 4'-glyCosylation dramatiCally deCreased aCtivity in the 'antioxidant' assays, whereas 3-substitutions produCed muCh smaller Changes. These results show that the preferentially-absorbed querCetin glyCosides in onions have markedly different biologiCal properties Compared with the aglyCone.
Al L Tappel - One of the best experts on this subject based on the ideXlab platform.
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proteCtion by multiple antioxidants against lipid peroxidation in rat liver homogenate
Lipids, 1996Co-Authors: Hao Chen, Al L TappelAbstract:The purpose of this study was to test the hypothesis that multiple antioxygeniC nutrients provide inCreased proteCtion against lipid peroxidative damage to rat liver. Rats were fed diets (i) defiCient in vitamin E and selenium (Diet 1), (ii) supplemented with vitamin E and selenium (Diet 2), (iii) supplemented with (ii) and in addition Trolox C,N-aCetylCysteine, Coenzyme Q0, and (+)-CateChin (Diet 3), or (iv) supplemented with (iii) and in addition β-Carotene, asCorbiC aCid palmitate, Canthaxanthin, and Coenzyme Q10 (Diet 4). Liver homogenates were obtained from three rats fed eaCh of the diets for six weeks and were inCubated at 37°C up to two hours with and without exogenous tertiary-butyl hydroperoxide (TBHP) or Cu2+. Lipid peroxidation was determined by measurement of thiobarbituriC aCid substanCes. Diets 2 and 3 signifiCantly proteCted againstin vivo hepatiC lipid peroxidation, and this proteCtion was augmented by Diet 4. Diets 2, 3, and 4 were proteCtive against mild oxidation induCed by TBHP or Cu2+. During inCubations with exogenous TBHP and Cu2+, there were only small differenCes between diets supplemented with antioxidants in inhibition of lipid peroxidation, indiCating that diets supplemented with vitamin E and selenium (Diet 2) may have provided the maximal proteCtion for liver. The possible meChanisms of proteCtion provided by multiple antioxidants in diets were disCussed. ProteCtion by multiple antioxidants against lipid peroxidation may translate to prevention of peroxidative damage to human tissue, a faCtor in human disease.
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proteCtion of vitamin e selenium Trolox C asCorbiC aCid palmitate aCetylCysteine Coenzyme q0 Coenzyme q10 beta Carotene Canthaxanthin and CateChin against oxidative damage to rat blood and tissues in vivo
Free Radical Biology and Medicine, 1995Co-Authors: Hao Chen, Al L TappelAbstract:AbstraCt Male Sprague-Dawley rats were fed either a vitamin E and selenium defiCient diet, a diet supplemented with vitamin E and selenium, or a diet supplemented with vitamin E, selenium, Trolox C, asCorbiC aCid palmitate, aCetylCysteine, Beta-Carotene, Canthaxanthin, Coenzyme Q 0 , Coenzyme Q 10 , and (+)-CateChin. Rats were injeCted with CBrCl 3 (0.05 mmol/100 g body weight) intraperitoneally. Oxidative damage to tissues was measured by formation of oxidized heme proteins (OHP) in blood, liver, kidney, heart, lung, and spleen. Diets supplemented with antioxidants showed proteCtion against oxidative damage Caused by CBrCl 3 . The proteCtion was dependent on the diversity and quantity of antioxidants in the diet. In general, diets supplemented with both fat soluble and water soluble antioxidants provided better proteCtion than diets supplemented only with vitamin E and selenium or with vitamin E, selenium, and fat soluble antioxidants.
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vitamin e selenium Trolox C asCorbiC aCid palmitate aCetylCysteine Coenzyme q β Carotene Canthaxanthin and CateChin proteCt against oxidative damage to kidney heart lung and spleen
Free Radical Research, 1995Co-Authors: Hao Chen, Al L TappelAbstract:Male Sprague-Dawley rats were fed diets that varied qualitatively and quantitatively in antioxidants. Kidney, heart, lung, and spleen homogenates were inCubated at 37°C with and without hydroperoxide or Fe+2. ProteCtion of antioxidants against oxidative damage to tissue was determined by measurement of oxidized heme proteins. Tissues from rats supplemented with dietary vitamin E and selenium showed proteCtion Compared to tissues from rats on the basal diet. Tissues from rats with diets Containing larger quantities of antioxidants and both fat soluble antioxidants: vitamin E, β-Carotene, Coenzyme Q10, asCorbiC aCid 6-palmitate and water soluble antioxidants: selenium, Trolox C, aCetylCysteine, Coenzyme Q0, (+)-CateChin, showed the highest proteCtion.
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proteCtion by vitamin e selenium Trolox C asCorbiC aCid palmitate aCetylCysteine Coenzyme q beta Carotene Canthaxanthin and CateChin against oxidative damage to liver sliCes measured by oxidized heme proteins
Free Radical Biology and Medicine, 1994Co-Authors: Hao Chen, Al L TappelAbstract:Male SD rats were fed a vitamin E- and selenium-defiCient diet, a diet supplemented with vitamin E and selenium, and diets supplemented with vitamin E, selenium, Trolox C, asCorbiC aCid palmitate, aCetylCysteine, beta-Carotene, Canthaxanthin, Coenzyme Q0, Coenzyme Q1, and (+)-CateChin. Liver sliCes were inCubated at 37°C with and without CBrCl3, t-butyl-hydroperoxide, Fe+2, or Cu+2. The effeCt of antioxidant nutrients on the oxidativedamage to rat liver was studies by measurement of the produCtion of oxidized heme proteins (OHP) during the oxidative reaCtions. Diet supplemented with vitamin E and selenium showed proteCtion against heme protein oxidation Compared to the antioxidatt-defiCient diet. Furthermore, inCreasing the diversity and quantity of antioxidants in the diets provided signifiCantly more proteCtion.
Jian Tu - One of the best experts on this subject based on the ideXlab platform.
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drug repurposing identified the Combination of Trolox C and Cytisine for the treatment of type 2 diabetes
Journal of Translational Medicine, 2014Co-Authors: Jian Tu, Wenbin An, Zhixin LiAbstract:BaCkground Drug-induCed gene expression dataset (for example ConneCtivity Map, CMap) represent a valuable resourCe for drug-repurposing, a Class of methods for identifying novel indiCations for approved drugs. ReCently, CMap-based methods have suCCessfully applied to identifying drugs for a number of diseases. However, Currently few gene expression based methods are available for the repurposing of Combined drugs. InCreasing evidenCe has shown that the Combination of drugs may valid for novel indiCations.
