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481.
Hoehle SI Pfeiffer E Sólyom AM Metzler M 《Journal of agricultural and food chemistry》2006,54(3):756-764
Curcumin and its natural congeners are of current interest because of their putative anti-inflammatory and anticarcinogenic activities, but knowledge about their metabolic fate is scant. In the present study conducted with precision-cut liver slices from male and female Sprague-Dawley rats, five reductive but no oxidative metabolites of curcumin and its demethoxy and bis-demethoxy analogues were observed and identified by HPLC and GC-MS analysis, mostly by comparison with authentic reference compounds. The major reductive metabolites were the hexahydrocurcuminoids in both male and female rat liver slices, whereas male rats formed more octahydro than tetrahydro metabolites and female rats more tetrahydro- than octahydrocurcuminoids. Tetrahydro, hexahydro, and octahydro metabolites were predominantly present as glucuronides, but a significant proportion of sulfate conjugates was also observed. The lack of formation of oxidative metabolites of curcumin and the ready generation of reductive metabolites were confirmed using rat liver microsomes and cytosol, respectively. Results of enzymatic hydrolysis studies conducted under various conditions revealed that curcumin and demethoxycurcumin are chemically less stable than bis-demethoxycurcumin, whereas the reductive metabolites of all three curcuminoids are stable compounds. This is the first report on the metabolism of demethoxycurcumin and bis-demethoxycurcumin. In view of the chemical instability of the parent curcuminoids, it is proposed to use their major phase I metabolites, that is, the stable hexahydro products, as biomarkers for exposure in clinical studies. 相似文献
482.
Bischofberger AS Ringer SK Geyer H Imboden I Ueltschi G Lischer CJ 《American journal of veterinary research》2006,67(4):577-582
OBJECTIVE: To determine via histologic examination and scintigraphy the effect of focused extracorporeal shock wave therapy (ESWT) on normal bone and the bone-ligament interface in horses. ANIMALS: 6 horses without lameness. PROCEDURE: Origins of the suspensory ligament at the metacarpus (35-mm probe depth) and fourth metatarsal bone (5-mm probe depth) were treated twice (days 0 and 16) with 2,000 shocks (energy flux density, 0.15 mJ/mm2). One forelimb and 1 hind limb were randomly treated, and the contralateral limbs served as nontreated controls. Bone scans were performed on days -1 (before ESWT), 3, 16, and 19. Histomorphologic studies of control and treated tissues were performed on day 30. RESULTS: ESWT significantly increased the number of osteoblasts but caused no damage to associated soft tissue structures and did not induce cortical microfractures. A significant correlation between osteoblast numbers and radiopharmaceutical uptake was noticed on lateral views of the hind limb on days 3 and 16 and on caudal views of the forelimb on day 3. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that ESWT has the potential to increase osteoblast numbers in horses. The correlation between increased osteoblast numbers and radio-pharmaceutical uptake 3 days and 16 days after the first ESWT suggested that stimulation of osteogenesis occurred soon after ESWT. No damage to bone or the bone-ligament interface should occur at the settings used in this study, and ESWT can therefore be administered safely in horses. 相似文献
483.
Changes in antioxidant content of tomato fruits in response to cultivar and nutrient solution composition 总被引:1,自引:0,他引:1
Fanasca S Colla G Maiani G Venneria E Rouphael Y Azzini E Saccardo F 《Journal of agricultural and food chemistry》2006,54(12):4319-4325
The aim of this study was to investigate the effect of cationic proportions (K/Ca/Mg) in the nutrient solution on fruit quality (quality attributes and antioxidant content) using a high-pigment, 'Lunarossa', tomato cultivar and a standard tomato cultivar ('Corfù') grown in soilless culture. Treatments were defined by a factorial combination of three nutrient solutions having different cationic proportions and two indeterminately growing round tomato cultivars. A high proportion of K in the nutrient solution increased the quality attributes (fruit dry matter, total soluble solids content) and the lycopene content of tomato fruit, whereas a high proportion of Ca improved tomato fruit yield and reduced the incidence of blossom-end rot (BER). The highest total antioxidant activity was observed in the treatment with a high proportion of Mg in the Lunarossa cultivar. The high-pigment hybrid has provided a higher antioxidant content (lycopene and alpha-tocopherol content) than the commercial hybrid, but it was more susceptible to BER and consequently less productive. 相似文献
484.
Ligianne Din Shirahigue Ingridy Simone Ribeiro Lia Ferraz de Arruda Sucasas Lika Anbe Paulo Vaz-Pires Marília Oetterer 《Journal Of Aquatic Food Product Technology》2018,27(6):712-721
This study investigated the efficacy of the aqueous fraction obtained after fractionating silage of tilapia (Oreochromis niloticus) and cobia (Rachycentron canadum) in supporting the growth of Escherichia coli and Staphylococcus aureus. The silages were prepared using combinations of citric, formic, and propionic acids. The aqueous fractions, used as test peptones, contained lower levels of total protein. The concentrations of 18 amino acids in all the samples were observed to be lower than those in the commercial peptone. Glutamic acid, lysine, glycine, and aspartic acid were present in higher concentrations than other amino acids, for both types of silage. Biomass production from E. coli culture ranged from 38.4 to 65.9 mg 100 mL?1 for all the tested treatments, while that for S. aureus was from 26.3 to 53.7 mg 100 mL?1. This indicated that products from fish silage were effective for bacterial growth in terms of biomass, by providing the main sources of nitrogen and carbon to facilitate their growth. The tested silages yielded similar efficiency to the commercial peptone. The findings revealed that it is feasible for the fish processing industry to incorporate freeze-dried by-products obtained after fractioning waste silage from the processing of tilapia and cobia. 相似文献
485.
486.
Neurological manifestations in dogs naturally infected by Leishmania infantum: descriptions of 10 cases and a review of the literature
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A. P. Giannuzzi M. Ricciardi A. De Simone F. Gernone 《The Journal of small animal practice》2017,58(3):125-138
In order to evaluate possible nervous system involvement in canine leishmaniasis, retrospective evaluation of all medical records of leishmaniotic dogs exhibiting neurological signs referred to our hospital over a 5‐year period was performed. The records of 10 dogs were reviewed. Depending on the neuroanatomical localisation, the dogs underwent advanced diagnostic imaging, cerebrospinal fluid analysis, electrodiagnostic testing and histopathologic evaluations. The final neurological diagnosis was: meningoencephalitis (n=2), brain haemorrhagic stroke (n=1), haemorrhagic choroiditis (n=1), meningomyelitis (n=2), ischaemic myelopathy (n=1), polymyositis (n=2) and peripheral neuropathy (n=1). This study confirms that both central and peripheral nervous systems can be affected by leishmaniasis and provides an overview on the possible etiopathogenetic mechanisms. In addition, clinical and diagnostic findings, therapy and follow‐up of affected dogs are described. 相似文献
487.
488.
Sara Carpi Egeria Scoditti Beatrice Polini Simone Brogi Vincenzo Calderone Peter Proksch Sherif S. Ebada Paola Nieri 《Marine drugs》2022,20(7)
The natural environment represents an important source of drugs that originates from the terrestrial and, in minority, marine organisms. Indeed, the marine environment represents a largely untapped source in the process of drug discovery. Among all marine organisms, sponges with algae represent the richest source of compounds showing anticancer activity. In this study, the two secondary metabolites pelorol (PEL) and 5-epi-ilimaquinone (EPI), purified from Dactylospongia elegans were investigated for their anti-melanoma activity. PEL and EPI induced cell growth repression of 501Mel melanoma cells in a concentration- and time-dependent manner. A cell cycle block in the G1 phase by PEL and EPI was also observed. Furthermore, PEL and EPI induced significant accumulation of DNA histone fragments in the cytoplasmic fraction, indicating a pro-apoptotic effect of both compounds. At the molecular level, PEL and EPI induced apoptosis through the increase in pro-apoptotic BAX expression, confirmed by the decrease in its silencing miR-214-3p and the decrease in the anti-apoptotic BCL-2, MCL1, and BIRC-5 mRNA expression, attested by the increase in their silencing miRNAs, i.e., miR-193a-3p and miR-16-5p. In conclusion, our data indicate that PEL and EPI exert cytotoxicity activity against 501Mel melanoma cells promoting apoptotic signaling and inducing changes in miRNA expression and their downstream effectors. For these reasons could represent promising lead compounds in the anti-melanoma drug research. 相似文献
489.
Lenise Freitas Mueller Júlio Csar Carvalho Balieiro Adrielle Matias Ferrinho Taiane da Silva Martins Rosana Ruegger Pereira da Silva Corte Tamyres Rodrigues de Amorim Joyce de Jesus Mangini Furlan Fernando Baldi Anglica Simone Cravo Pereira 《Animal Science Journal》2019,90(8):1078-1089
The study evaluated the effect of gender status on carcass and meat quality of feedlot Angus × Nellore cattle. A total of 176 cattle, 20 months old, were confined for 190‐days and assigned to four treatments: bulls, immunocastrated, steers, and heifers. Bulls had greater rib eye area and HCW (p = 0.0001). Heifers had increased fat thickness (p = 0.0001). Steers and heifers had higher marbling scores (p = 0.0001). There was interaction between gender and aging time for Warner‐Bratzler Shear Force (p = 0.0002), L* (p = 0.0118), and b* (p = 0.0113) values of beef. The sensory panel results showed that beef from bulls had the lowest consumer overall acceptance (p = 0.0278). Especially, regardless tenderness, steers and immunocastrated beef were considered tender, independent of aging time. Beef produced by heifers, steers, and immunocastrated is considered to be of higher quality than bulls. Thus, it is may be an interesting alternative to produce high‐quality beef than bulls, to attend the consumer demand for high‐quality products. Additionally, the low fatty acids n6 levels and low n6:n3 ratio, high levels of CLA, MUFAs, and oleic acid suggests that the heifer meat is favorable for human health. 相似文献
490.
Simone Savoia Andrea Albera Alberto Brugiapaglia Liliana Di Stasio Alessio Cecchinato Giovanni Bittante 《畜牧与生物技术杂志(英文版)》2021,(3):1214-1225
Background:The possibility of assessing meat quality traits over the meat chain is strongly limited, especially in the context of selective breeding which requi... 相似文献