Total oxidant scavenging capacity of Euterpe oleracea Mart. (açaí) seeds and identification of their polyphenolic compounds     

Rodrigues RB  Lichtenthäler R  Zimmermann BF  Papagiannopoulos M  Fabricius H  Marx F  Maia JG  Almeida O 《Journal of agricultural and food chemistry》2006,54(12):4162-4167

The antioxidant capacity of methanol and ethanol seed extracts from Euterpe oleracea Mart. (a?aí) against the reactive oxygen species (ROS) peroxyl radicals, peroxynitrite, and hydroxyl radicals was studied with the total oxidant scavenging capacity (TOSC) assay in a modified and automated version. Cold methanol digestion was the most efficient extraction method with respect to the antioxidant capacity. The extracts exhibit good antioxidant capacity against peroxyl radicals, similar to the capacity of the pulp. The antioxidant capacity against peroxynitrite and hydroxyl radicals is even higher. The main antioxidants identified by HPLC-MS and HPLC-CEAD are five different procyanidins (di- through pentamers); furthermore, protocatechuic acid and epicatechin were identified as minor compounds. Determination of TOSC values of HPLC seed extract fractions indicates that the procyanidins contribute substantially to the overall antioxidant capacity. In addition, however, other compounds that have not yet been identified are responsible for a large part of the observed antioxidant capacity.  相似文献   

c‐Kit Mutation and Localization Status as Response Predictors in Mast Cell Tumors in Dogs Treated with Prednisone and Toceranib or Vinblastine          下载免费PDF全文

K.M. Weishaar  E.J. Ehrhart  A.C. Avery  J.B. Charles  R.E. Elmslie  D.M. Vail  C.A. London  C.A. Clifford  J.C. Eickhoff  D.H. Thamm 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):394-405

Background

KIT inhibitors, such as toceranib (TOC), and vinblastine (VBL) have not been prospectively compared in the treatment of macroscopic mast cell tumors (MCTs). Also, it is unknown whether VBL or TOC is superior for treating MCT without c‐kit mutations.

Hypothesis/Objectives

To determine the value of KIT genotyping and localization in treatment decisions for dogs with macroscopic MCT. We hypothesized that c‐kit mutated MCT would have a better response to TOC than VBL.

Animals

Eighty‐eight client‐owned dogs with macroscopic MCT.

Methods

Prospective, randomized trial. Dogs were randomized to TOC (2.75 mg/kg EOD) or VBL (2.5 mg/m² weekly × 4 then EOW) by KIT localization and c‐kit mutation status using an adaptive randomization scheme.

Results

Sixty dogs were allocated to TOC and 28 to VBL. Of the dogs receiving TOC, 20% had c‐kit mutations, compared to 30% receiving VBL (P = 0.74). Overall response rates were 46% (TOC) and 30% (VBL) (odds ratio = 1.56 [0.62–3.92]; P = 0.28). Median progression‐free survival (PFS) for dogs receiving VBL was 78 days (7–1,521) and for TOC 95.5 (14–990); hazard ratio (HR) = 1.34 [0.72–2.50]; P = 0.36. Median overall survival (OS) was 241.5 days (10–1,521) for the VBL group and 159 (20–990) for the TOC group; HR = 0.80 ([0.45–1.41]; P = 0.44).

Conclusions and Clinical Importance

Neither PFS nor OS was significantly different between treatment groups. As the proportion of dogs with c‐kit mutations was not different between treatment groups in this population of dogs, c‐kit mutation status did not predict treatment response.  相似文献   

Investigation of Host Responses of Different Potato Genotypes at Tissue, Cellular and Subcellular Levels After Infection with Phytophthora infestans     

Qingmei Han  Ramona Thieme  Xiaoning Gao  Zhensheng Kang  Lili Huang 《American Journal of Potato Research》2013,90(6):524-532

In histological and cytological investigations, the infection process of Phytophthora infestans, the late blight pathogen, was comparatively studied in several potato cultivars and somatic hybrid genotypes and their parents using fluorescence microscopy and electron microscopy methods. The results showed that germination of zoospores of P. infestans and frequency of invading by infection hyphae did not differ among the cultivar-pathogen interactions, but, extension of hyphae in host cells markedly differed among these genotypes. In the susceptible genotypes the pathogen grew rapidly inter- and intracellularly, 12 h after inoculation (hai), and some digital like haustoria were formed and the cytoplasm of the host cells became disorganized. In the resistance genotypes, the pathogen was restricted to the site of initial penetration, although some hyphae could penetrate the epidermal cell, however, the host cells produced resistance responses, such as formed wall appositions when in contact with hyphae, and no haustoria like structures were found. In the somatic hybride genotypes, the host response was different according to their parents as shown by transmission electron microscopy. In the hybrid genotype 1508/2, like in the wild species S. bulbocastanum, no hyphae were found in host cells. In the other genotypes, hyphae of P. infestans spread intercellularly and formed haustoria, but the cytoplasm of hyphae and haustoria was disorganized and host cell resistant responses often appeared, such as, host cells were disorganized and necrotic and cell wall apposition were observed.  相似文献   

Gas chromatography/electron-capture negative ion mass spectrometry for the quantitative determination of 2- and 3-hydroxy fatty acids in bovine milk fat     

Jenske R  Vetter W 《Journal of agricultural and food chemistry》2008,56(14):5500-5505

2- and 3-hydroxy fatty acids (2- and 3-OH-FAs) are bioactive substances reported in sphingolipids and bacteria. Little is known of their occurrence in food. For this reason, a method suitable for the determination of OH-FAs at trace levels in bovine milk fat was developed. OH-FAs (and conventional fatty acids in samples) were converted into methyl esters and the hydroxyl group was derivatized with pentafluorobenzoyl (PFBO) chloride to give PFBO- O-FA methyl esters. These derivatives with strong electron affinity were determined by gas chromatography interfaced to mass spectrometry using electron-capture negative ion in the selected ion monitoring mode (GC/ECNI-MS-SIM). This method proved to be highly sensitive and selective for PFBO-O-FA methyl esters. For the analysis of samples, two internal standards were used. For this purpose, 9,10-dideutero-2-OH-18:0 methyl ester (ISTD-1) from 2-OH-18:1(9 c) methyl ester as well as the ethyl ester of 3-PFBO-O-12:0 (ISTD-2) was synthesized. ISTD-1 served as a recovery standard whereas ISTD-2 was used for GC/MS measurements. The whole-sample cleanup consisted of accelerated solvent extraction of dry bovine milk, addition of ISTD 1, saponification, conversion of fatty acids into methyl esters by use of boron trifluoride, separation of the methyl esters of OH-FAs from nonsubstituted FAs on activated silica, conversion of OH-FAs methyl esters into PFBO-O-FA methyl esters, addition of ISTD-2, and measurement by GC/ECNI-MS-SIM. By this method, ten OH-FAs were quantified in bovine milk fat with high precision in the range from 0.02 +/- 0.00 to 4.49 +/- 0.29 mg/100 g of milk fat.  相似文献   

Grain cadmium and zinc concentrations in wheat as affected by genotypic variation and potassium chloride fertilization   总被引：1，自引：0，他引：1  

Xiaopeng Gao  Ramona M. Mohr  Debra L. McLaren  Cynthia A. Grant 《Field Crops Research》2011,122(2):125-103

Thirteen bread wheat (Triticum aestivum L.) and two durum wheat (Triticum turgidum L. var. durum) cultivars were grown over six site-years to identify differences in grain Cd and Zn concentrations, as affected by genotypic variation and soil application of potassium chloride (KCl) fertilizer. Application of KCl fertilizer did not consistently affect grain Cd concentration of wheat cultivars, but increased average grain yield and decreased average grain Zn in 4 of 6 site-years. However, soil type and year had significant effects on grain Cd and Zn, indicating a strong environmental effect on grain quality. Grain concentrations of Cd and Zn were generally lower for the clay loam (CL) than the fine sandy loam (FSL) soils. The wheat cultivars showed significant genotypic differences in grain concentrations of Cd and Zn, suggesting the potential of breeding to reduce Cd and increase Zn concentrations in grain. The two durum cultivars contained high concentrations of Cd but not Zn compared to the bread wheat. The interaction between cultivars and site-years was significant for grain Zn, but not for grain Cd, suggesting that grain Cd is a more stable trait than grain Zn across environments. Grain Zn and Cd were not related to each other but they both correlated negatively with grain yield. The lack of relationship between Zn and Cd suggests that breeding for enhanced Zn concentration can be attained without necessarily affecting grain Cd concentration. The negative relationship between Cd and Zn concentration and dry matter yield was likely the result of biological dilution, suggesting that genetic improvement leading to increased yield may concurrently decrease mineral concentration. Results of this study are useful to improve the mineral composition of wheat used for human consumption through the development of cultivars and use of agronomic management practices that increase Zn and/or reduce Cd concentrations in wheat grain.  相似文献   

Somaklonale Variation des Krautes,der Vegetationslänge und des Ertrages bei Kartoffeln     

Ramona Thieme  Helmut Griess 《Potato Research》1996,39(3):355-365

Zusammenfassung In vergleichenden Untersuchungen unterschiedlicher Züchtungsstrategien wurden in 5 Zyklen insgesamt ca. 13000 aus Kallus regenerierte Somaklone von 14 sehr unterschiedlichen Spendern (Sorten und Zuchtst?mmen) getopft und unter mehrstufiger Merzung auf wirtschaftlich bedeutsame Merkmale: Krautwachstum, Vegetationsl?nge und Knollenertrag geprüft. Ein Netz von Kontrollparzellen erm?glichte es, der Auswertung ein Zweipopulationsproblem zugrunde zu legen. Neben den Prozents?tzen signifikanter Abweicher werden Ausbeutequoten, d.h. der Anteil von positiven Abweichern bzw. Invarianten in % der als Regenerate getopften Somaklone ausgewiesen. Starke Krautanomalien traten selten auf. Die Vegetationsl?nge variierte um eine Reifegruppe. Der Anteil negativer Abweicher in Kraut und Ertrag überwog eindeutig. Es konnte über zwei bis drei Feldgenerationen ein kleiner, aber züchterisch relevanter Anteil signifikant positiver (Ausbeutequote=max. zehntel Prozent) bzw. dem Spender gleichender Somaklone nachgewiesen werden. Die Spenderklone reagierten unterschiedlich. So zeigte die Sorte Astilla und Dorisa N viele wüchsige Klone mit h?heren Ertr?gen, w?hrend die Sorte Lipsi N vergleichsweise eine geringere Variabilit?t aufwies.  相似文献   

The Effect of Substituent,Degree of Acetylation and Positioning of the Cationic Charge on the Antibacterial Activity of Quaternary Chitosan Derivatives     

Priyanka Sahariah  Vivek S. Gaware  Ramona Lieder  Sigríeur Jónsdóttir  Martha á. Hjálmarsdóttir  Olafur E. Sigurjonsson  Már Másson 《Marine drugs》2014,12(8):4635-4658

A series of water-soluble cationic chitosan derivatives were prepared by chemoselective functionalization at the amino group of five different parent chitosans having varying degrees of acetylation and molecular weight. The quaternary moieties were introduced at different alkyl spacer lengths from the polymer backbone (C-0, C-2 and C-6) with the aid of 3,6-di-O-tert-butyldimethylsilyl protection of the chitosan backbone, thus allowing full (100%) substitution of the free amino groups. All of the derivatives were characterized using ¹H-NMR, ¹H-¹H COSY and FT-IR spectroscopy, while molecular weight was determined by GPC. Antibacterial activity was investigated against Gram positive S. aureus and Gram negative E. coli. The relationship between structure and activity/toxicity was defined, considering the effect of the cationic group’s structure and its distance from the polymer backbone, as well as the degree of acetylation within a molecular weight range of 7–23 kDa for the final compounds. The N,N,N-trimethyl chitosan with 100% quaternization showed the highest antibacterial activity with moderate cytotoxicity, while increasing the spacer length reduced the activity. Trimethylammoniumyl quaternary ammonium moieties contributed more to activity than 1-pyridiniumyl moieties. In general, no trend in the antibacterial activity of the compounds with increasing molecular weight or degree of acetylation up to 34% was observed.  相似文献   

Activation of endothelial cell protease activated receptor 1 by the protein C pathway   总被引：1，自引：0，他引：1  

Riewald M  Petrovan RJ  Donner A  Mueller BM  Ruf W 《Science (New York, N.Y.)》2002,296(5574):1880-1882

The coagulant and inflammatory exacerbation in sepsis is counterbalanced by the protective protein C (PC) pathway. Activated PC (APC) was shown to use the endothelial cell PC receptor (EPCR) as a coreceptor for cleavage of protease activated receptor 1 (PAR1) on endothelial cells. Gene profiling demonstrated that PAR1 signaling could account for all APC-induced protective genes, including the immunomodulatory monocyte chemoattractant protein-1 (MCP-1), which was selectively induced by activation of PAR1, but not PAR2. Thus, the prototypical thrombin receptor is the target for EPCR-dependent APC signaling, suggesting a role for this receptor cascade in protection from sepsis.  相似文献   

High yield of PVY-free potato plants from axillary bud cultures after application of lysolecithin analogues and aminoadamantane     

B. Pett  S. Kluge  Ramona Thieme  P. Nuhn  H. -P. Kertscher 《Potato Research》1986,29(1):169-172

Summary Lysolecithin analogues and aminoadamantane were tested in vitro for their antiphytoviral effect on axillary bud cultures of potato infected with potato virus Y (PVY). Ethyllecithin added to the medium (700 mg/l) gave the best therapeutic effect on axenic axillary buds that were 1.67 mm long. Applying that compound, explant size may be increased and lead to virus elimination without thermal treatment. Thus viruses can be eliminated more effectively than with conventional methods.  相似文献