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641.
Rossoni G Grande S Galli C Visioli F 《Journal of agricultural and food chemistry》2005,53(26):10291-10296
Endothelial dysfunction, which is more often observed in conduit arteries such as the aorta, carotid, femoral, and brachial arteries, is largely due to alterations in cellular signal transduction initiated by an escalating cycle of damage triggered by oxidative stress. This phenomenon is exacerbated in the elderly, where a progressive loss of vascular endothelial function and concurrent loss of vasomotor control is frequent. In a previous study, we demonstrated that the wild artichoke (Cynara cardunculus) is able to increase the production of the vasorelaxant factor nitric oxide by cultured aortic endothelial cells. We now extended that study to verify (1) the vasorelaxant potential of C. cardunculus on isolated rat aortic rings and (2) whether the vasomodulating properties of C. cardunculus are maintained in vivo, after administration to aged rats. The results demonstrate that the wild artichoke and its main components, namely, luteolin and apigenin, improve aortic relaxation when added to the incubation bath. Moreover, the feeding of wild artichoke [10 mg (kg of polyphenols)(-1) day(-1)] to aged rats significantly restores proper vasomotion, to a degree similar to that observed in young animals. This study provides further justification to the advice to consume wild greens as part of a balanced diet and suggests that close attention should be paid to the diet of the elderly, because it can effectively modulate important parameters of cardiovascular risk. 相似文献
642.
Fabiana Micieli Ludovica Chiavaccini Giuseppina Mennonna Giovanni Della Valle Francesco Prisco Leonardo Meomartino Giancarlo Vesce 《Veterinary anaesthesia and analgesia》2021,48(1):107-115
ObjectiveTo describe the gross and microscopic anatomy of the sciatic nerve paraneural sheath and to report an ultrasound (US)-guided subparaneural approach to the sciatic nerve in dogs, comparing two different volumes of injectate.Study designProspective, randomized, anatomical study.AnimalsA group of nine middle-sized adult Mongrel canine cadavers (18 limbs).MethodsThe sciatic nerves of three pelvic limbs of two canine cadavers were identified, exposed and isolated between the greater trochanter and the popliteal fossa for gross anatomical and microscopic examination. An additional three pelvic limbs were surgically dissected on the lateral surface of the limb; the sciatic nerves were isolated, and a 26 gauge over-the-needle catheter was inserted through the paraneural sheath under direct visualization. A methylene blue solution was then slowly injected into the subparaneural compartment through the catheter under US visualization using an 8–13 MHz linear-array transducer. Subsequently, 12 pelvic limbs (six cadavers) were randomly allocated to one of two groups; using US-guided percutaneous subparaneural approach, either 0.1 or 0.05 mL kg–1of a 1:1 solution of methylene blue and 0.5% bupivacaine was injected. The spread of the dye solution and the amount of nerve staining were macroscopically scored. The stained sciatic nerves with their sheaths were then harvested for microscopic examination.ResultsThe paraneural sciatic nerve sheath was easily identified distinct from the nerve trunk both macroscopically and with US visualization, and microscopically. Complete staining was achieved in five of six (83.3%) sciatic nerves in each group; no difference was found in the amount of staining between the two groups. Microscopically, no signs of sciatic nerve intraneural injection were observed.Conclusions and clinical relevanceThe US-guided subparaneural injection of 0.05 mL kg–1 of a dye injectate resulted in satisfactory nerve staining without evidence of sciatic nerve intraneural injection. 相似文献
643.
Bianca Conturba Chiara Maria Lo Feudo Luca Stucchi Giovanni Stancari Lara Olivieri Francesco Ferrucci 《Veterinary dermatology》2021,32(3):290-e78
The aim of the present work was to describe a case of recurrent capillary haemangioma at the coronary border of the left front limb in a 6-month-old thoroughbred filly successfully treated with diode laser ablation and adjunctive laser photocoagulation therapy. 相似文献
644.
There is a growing interest on the potential interplay between weather, habitat, and interspecific competition on population dynamics of wild herbivores. Favorable environmental conditions may buffer the negative effects of competition; conversely, competition may be expected to be stronger under harsh environmental conditions. We investigated relationships between competitor abundance, weather, and habitat cover on density and local distribution of a medium-sized herbivore, the roe deer Capreolus capreolus, as well as its spatial overlap with fallow deer Dama dama in a Mediterranean protected area. Over 11 years (2007–2017), roe deer density was not affected by spring–summer rainfall in the previous year and decreased with increasing density of fallow deer in the previous year. Hence, over the considered temporal scale, results supported a major role of competition over weather in influencing population trends of roe deer. At a finer spatial scale, roe deer occupancy was negatively affected by local abundance of fallow deer, especially in “poorer” habitats. We found a slight support for a positive effect of fallow deer density on interspecific spatial overlap. Moreover, fine-scale spatial overlap between deer species increased with decreasing rainfall in spring–summer. Fallow deer were introduced to our study area in historical times and their role as superior competitors over roe deer has been found also in other study areas. We suggest a potential role of harsh weather conditions during the growing season of vegetation (i.e. scarce rainfall) in triggering the potential for ecological overlap, emphasizing the negative effects of interspecific competition. 相似文献
645.
Mass spectrometry has been used to map chymosin from a fermentative source. The copresence of the two known genetic variants A (Asp(244)) and B (Gly(244)) was ascertained in bovine chymosin. By contrast, either the A or the B genetic variant occurred in the three commercial samples of recombinant calf chymosin (RCC). Specific biomarker proteins were searched to identify the enzyme source, in both bovine chymosin and RCC samples. Analyzing the derived tryptic peptides, evidence was provided that RCC and bovine chymosin are mainly formed by (1-323), (3-323), and (40p-323) (suffix "p" denotes residues in the pro-segment region of chymosin), whereas the minor components, (4-323), (5-323), and (6-323), were only detected in bovine chymosin. Additionally, the three commercial RCC samples contained the protein species (1-323), (38p-323), (39p-323), and (40p-323) and the shorter form (3-323). Differentiation of the natural and bioengineered enzyme is based upon the detection of these unique minor components by mass spectrometry. 相似文献
646.
Paola Cellini Legittimo Giovanni Piccardi Francesco Pantani 《Water, air, and soil pollution》1980,14(1):435-441
The parameters affecting the determination of some heavy metals in rainwater of Florence and its suburbs are investigated The maximum sensitivity for zinc determination by DPASV is obtained for a pulse amplitude of +50 mV. Samples of rainwater, collected in the center of Florence, show a metal concentration which is higher than samples collected in the suburb for the same meteorological event. Other sampling along the Tyrrenean seashore revealed a higher metal concentration in relation to the section of the coast that receives the polluted waters of the Arno river. In samples acidified to pH = 2, Cu and Zn are partially released in a very slow process. 相似文献
647.
Núñez Sellés AJ Vélez Castro HT Agüero-Agüero J González-González J Naddeo F De Simone F Rastrelli L 《Journal of agricultural and food chemistry》2002,50(4):762-766
An aqueous decoction of mango (Mangifera indica L.) stem bark has been developed in Cuba on an industrial scale to be used as a nutritional supplement, cosmetic, and phytomedicine. Previously we reported its antioxidant activity, and we concluded that the product could be useful to prevent the production of reactive oxygen species and oxidative tissue damage in vivo. A phytochemical investigation of mango stem bark extract has led to the isolation of seven phenolic constituents: gallic acid, 3,4-dihydroxy benzoic acid, gallic acid methyl ester, gallic acid propyl ester, mangiferin, (+)-catechin, (-)-epicatechin, and benzoic acid and benzoic acid propyl ester. All structures were elucidated by ES-MS and NMR spectroscopic methods. Quantitative analysis of the compounds has been performed by HPLC, and mangiferin was found to be the predominant component. Total polyphenols were assayed also by the Folin-Ciocalteu method. The free sugars and polyols content was also determined by GC-MS. 相似文献
648.
Benitez-Nelson CR Bidigare RR Dickey TD Landry MR Leonard CL Brown SL Nencioli F Rii YM Maiti K Becker JW Bibby TS Black W Cai WJ Carlson CA Chen F Kuwahara VS Mahaffey C McAndrew PM Quay PD Rappé MS Selph KE Simmons MP Yang EJ 《Science (New York, N.Y.)》2007,316(5827):1017-1021
Mesoscale eddies may play a critical role in ocean biogeochemistry by increasing nutrient supply, primary production, and efficiency of the biological pump, that is, the ratio of carbon export to primary production in otherwise nutrient-deficient waters. We examined a diatom bloom within a cold-core cyclonic eddy off Hawaii. Eddy primary production, community biomass, and size composition were markedly enhanced but had little effect on the carbon export ratio. Instead, the system functioned as a selective silica pump. Strong trophic coupling and inefficient organic export may be general characteristics of community perturbation responses in the warm waters of the Pacific Ocean. 相似文献
649.
Ruggeri L Capanni M Urbani E Perruccio K Shlomchik WD Tosti A Posati S Rogaia D Frassoni F Aversa F Martelli MF Velardi A 《Science (New York, N.Y.)》2002,295(5562):2097-2100
T cells that accompany allogeneic hematopoietic grafts for treating leukemia enhance engraftment and mediate the graft-versus-leukemia effect. Unfortunately, alloreactive T cells also cause graft-versus-host disease (GVHD). T cell depletion prevents GVHD but increases the risk of graft rejection and leukemic relapse. In human transplants, we show that donor-versus-recipient natural killer (NK)-cell alloreactivity could eliminate leukemia relapse and graft rejection and protect patients against GVHD. In mice, the pretransplant infusion of alloreactive NK cells obviated the need for high-intensity conditioning and reduced GVHD. NK cell alloreactivity may thus provide a powerful tool for enhancing the efficacy and safety of allogeneic hematopoietic transplantation. 相似文献
650.
Alessandra Marti Alberto Barbiroli Francesco Bonomi Andrea Brutti Stefania Iametti Mauro Marengo Matteo Miriani Maria Ambrogina Pagani 《Cereal Chemistry》2014,91(4):318-320
The ability of high hydrostatic pressure processing to promote changes in both the structural properties of fiber and the interaction of fiber with water were addressed. Both coarse and fine bran from milling of common wheat were considered. Treatment‐induced morphological changes were most pronounced in fine bran, whereas treatment of coarse bran resulted in the largest change in water‐holding capacity. The significance of the process‐induced changes is discussed in terms of their practical relevance in the production of fiber‐enriched foods. 相似文献