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961.
Aparicio-Fernández X García-Gasca T Yousef GG Lila MA González de Mejia E Loarca-Pina G 《Journal of agricultural and food chemistry》2006,54(6):2116-2122
The antiproliferative effects of 100% methanol crude extract and of Toyopearl and silica gel fractions from the seed coats of black Jamapa beans (Phaseolus vulgaris L.) were evaluated using HeLa, human adenocarcinoma cells, and HaCaT, human premalignant keratinocytes. The 100% methanol crude extract [172.2 microM equiv of (+)-catechin] increased adhesion of HeLa cells; however, 3- and 5-fold higher concentrations decreased the number of cells attached as a function of the treatment time. The highest concentration tested diminished the cell adhesion until 40% (after 24 h) to almost 80% (after 72 h). The IC50 values showed that the 100% methanol crude extract was the most effective inhibitor of HeLa cell proliferation, even when it was dissolved in dimethylsulfoxide (DMSO) [34.5 microM equiv of (+)-catechin] or in medium [97.7 microM equiv of (+)-catechin]. The Toyopearl 5 (TP5) fraction and silica gel 2 (SG2) fraction inhibited 60% of the HeLa cell proliferation. The IC50 was 154 microM equiv of (+)-catechin of the 100% methanol crude extract on HaCaT cells. Toyopearl fractions TP4 and TP6 significantly inhibited HaCaT cell proliferation, but the silica gel fractions did not have a significant effect. The 100% methanol crude extract (35 microg of dry material/mL) decreased the number of HeLa cells in the G0/G1 phase from 68.9% (for control cells) to 51.4% (for treated cells) and increased apoptosis (2.9 and 21.2% for control and treated cells, respectively). The results indicated that black Jamapa beans could be a source of polyphenolic compounds, which have an inhibitory effect toward HeLa cancer cells but are less aggressive on HaCaT premalignant cells. 相似文献
962.
Gutiérrez A Rodríguez IM del Río JC 《Journal of agricultural and food chemistry》2006,54(6):2138-2144
The chemical composition of lignin and lipids of bast fibers from industrial hemp (Cannabis sativa) used for high-quality paper pulp production was studied. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) of fibers showed a lignin with a p-hydroxyphenyl:guaiacyl:syringyl unit (H:G:S) molar proportion of 13:53:34 (S/G ratio of 0.64). p-Hydroxycinnamic acids, namely, p-coumaric and ferulic acids, were found in only trace amounts. Among the lipids, the main compounds identified by GC/MS of the hemp fibers extracts were series of n-alkanes, free and esterified sterols and triterpenols, waxes, and long-chain n-fatty acids. Other compounds such as n-aldehydes, n-fatty alcohols, steroid hydrocarbons, and steroid and triterpenoid ketones as well as steryl glycosides were also found. 相似文献
963.
1. The effect of dietary formic acid on performance, digestibility, intestinal histomorphology and plasma metabolite levels of broiler chickens was studied. 2. An experiment with 120 Ross male broiler chickens was conducted from 1 to 42 d of age at the laboratory. There were 4 treatment groups: control (C), 10 mg/kg feed avilamycin (AV) and formic acid at two concentrations, 5 and 10 g/kg feed (FA5 and FA10, respectively). 3. No differences in weight gain, feed intake or feed conversion ratio were observed in male broiler chickens fed on the different diets. 4. An effect of the additives on ileal dry matter (DM) digestibility at 42 d of age was detected with the finisher diets; AV and 10 g/kg of feed formic acid slightly improved ileal DM digestibility compared to the other treatment groups. 5. Jejunum pH was not affected when 5 or 10 g/kg formic acid was added, and the results do not clearly show a positive effect of formic acid on the intestinal histomorphology. 6. No differences were noticed for blood metabolites in the different diets, and the levels of calcium and phosphorus in the plasma were not altered by formic acid addition. 7. In conclusion, when using broiler chickens under conditions of good hygiene, dietary formic acid did not have a clear positive effect on performance, intestinal histomorphology or plasma metabolite levels; however, there was a slight positive effect on the ileal digestibility of nutrients. 相似文献
964.
Castillo C Benedito JL Méndez J García-Partida P Vázquez P Pereira V López-Alonso M Hernández J 《Berliner und Münchener tier?rztliche Wochenschrift》2006,119(11-12):480-485
The aim of this study was to evaluate the effects of two dietary supplements (monensin and a live yeast culture) on acid-base balance in steers maintained in a commercial feedlot system, considering effects over the growing period (14 to 23 weeks of age). A 63-day feedlot study was performed using 42 double-muscled Belgian Blue steers. Steers were allotted randomly to one of the three study groups: (1) control group [no supplementation, C], (2) monensin supplementation [MON] at a concentration of 30 mg/kg (DM basis), and (3) live Saccharomyces cerevisiae strain supplementation [SACC] at a dose of 500 mg/kg (DM basis).Venous blood samples were collected for the measurement of acid-base parameters and L-lactate. Production parameters were also used as a complementary tool for understanding the internal changes associated with supplementation. Our results show that during the study period no statistical differences were observed between supplemented and control steers, although non-supplemented animals tended to gain more efficiently than those fed monensin or yeast. Nevertheless, taking into account blood parameters, these control animals showed a greater risk of acid overload due to a more marked decline in blood buffer levels over time in comparison with supplemented steers although no differences were observed between monensin or yeast supplemented animals. Additionally, significant effect of supplementation was observed in packed cell volume (PCV) values. 相似文献
965.
Martins EA Silva LC Baccarin RY 《The Canadian veterinary journal. La revue veterinaire canadienne》2006,47(5):471-474
The objective of this study was to evaluate, through ultrasonography, the effect of medial patellar desmotomy. Middle patellar desmitis, enthesophytes in the patella, and irregularities in the cartilage of the femoral trochlear groove were observed. Medial patellar desmotomy leads to lesions in the stifle, and restriction of movement does not prevent these lesions from occurring. 相似文献
966.
Savlík M Fimanová K Szotáková B Lamka J Skálová L 《Research in veterinary science》2006,80(3):267-274
Fenbendazole (FEN) and flubendazole (FLU) are benzimidazole anthelmintics often used in pig management for the control of nematodoses. The in vivo study presented here was designed to test the influence of FLU and FEN on cytochrome P4501A and other cytochrome P450 (CYP) isoforms, UDP-glucuronosyl transferase and several carbonyl reducing enzymes. The results indicated that FEN (in a single therapeutic dose as well as in repeated therapeutic doses) caused significant induction of pig CYP1A, while FLU did not show an inductive effect towards this isoform. Some of the other hepatic and intestinal biotransformation enzymes that were assayed were moderately influenced by FEN or FLU. Strong CYP1A induction following FEN therapy in pigs may negatively affect the efficacy and pharmacokinetics of FEN itself or other simultaneously or consecutively administered drugs. From the perspective of biotransformation enzyme modulation, FLU would appear to be a more convenient anthelmintic therapy of pigs than FEN. 相似文献
967.
Martínez J Segalés J Aduriz G Atxaerandio R Jaro P Ortega J Peris B Corpa JM 《Research in veterinary science》2006,81(1):92-98
Multifocal interstitial nephritis in pigs has been associated with several infectious agents. The objective of the present study was to investigate several different potential infectious agents associated with "white-spotted" kidneys in pigs suffering from wasting at slaughter (aged 6-8 months). Twenty-nine case kidneys (with a "white-spotted" gross appearance) classified into 3 macroscopic lesional grades, and 15 control kidneys (lacking gross lesions), were obtained from a pig abattoir. Laboratory analyses to detect potential associations with the aforementioned pathological condition with Leptospira spp., porcine circovirus type 2 (PCV2), porcine parvovirus (PPV), porcine reproductive and respiratory syndrome virus (PRRSV), and bacteria, were carried out. Microscopically, interstitial nephritis with a lymphofollicular inflammatory pattern (follicular nephritis) was observed in both case and control kidneys, with a higher frequency seen in the former ones. No leptospires were identified, although antibodies to the Pomona and Bratislava serovars were detected. Some pyogenic bacteria were also isolated from both case and control kidneys. PCV2 nucleic acid was only detected in 1 case kidney. PRRSV antigen was not found in any tested sample. Some pigs were tested positive for PPV by serology. Apparently, none of the studied agents were specifically associated as being the potential cause of the renal lesions in the studied wasted pigs. The fact that these chronic lesions may have been the consequence of a previous infection with one of these studied microorganisms, or more, and eventually with other non-tested infectious agents during the growing-finishing period, cannot be ruled out. 相似文献
968.
Argüelles D Carmona JU Pastor J Iborra A Viñals L Martínez P Bach E Prades M 《Research in veterinary science》2006,81(2):237-245
The aim of this study was to evaluate single and double centrifugation tube methods for concentrating equine platelets. Whole blood samples were collected from clinically normal horses and processed by use of single and double centrifugation tube methods to obtain four platelet concentrates (PCs): PC-A, PC-B, PC-C, and PC-D, which were analyzed using a flow cytometry hematology system for hemogram and additional platelet parameters (mean platelet volume, platelet distribution width, mean platelet component concentration, mean platelet component distribution width). Concentrations of transforming growth factor beta 1 (TGF-beta(1)) were determined in all the samples. Platelet concentrations for PC-A, PC-B, PC-C, and PC-D were 45%, 44%, 71%, and 21% higher, respectively, compared to the same values for citrated whole blood samples. TGF-beta(1) concentrations for PC-A, PC-B, PC-C, and PC-D were 38%, 44%, 44%, and 37% higher, respectively, compared to citrated whole blood sample values. In conclusion, the single and double centrifugation tube methods are reliable methods for concentrating equine platelets and for obtaining potentially therapeutic TGF-beta(1) levels. 相似文献
969.
Zafra-Gómez A Garballo A Morales JC García-Ayuso LE 《Journal of agricultural and food chemistry》2006,54(13):4531-4536
A fast, simple, and reliable method for the isolation and determination of the vitamins thiamin, riboflavin, niacin, pantothenic acid, pyridoxine, folic acid, cyanocobalamin, and ascorbic acid in food samples is proposed. The most relevant advantages of the proposed method are the simultaneous determination of the eight more common vitamins in enriched food products and a reduction of the time required for quantitative extraction, because the method consists merely of the addition of a precipitation solution and centrifugation of the sample. Furthermore, this method saves a substantial amount of reagents as compared with official methods, and minimal sample manipulation is achieved due to the few steps required. The chromatographic separation is carried out on a reverse phase C18 column, and the vitamins are detected at different wavelengths by either fluorescence or UV-visible detection. The proposed method was applied to the determination of water-soluble vitamins in supplemented milk, infant nutrition products, and milk powder certified reference material (CRM 421, BCR) with recoveries ranging from 90 to 100%. 相似文献
970.
Barrera-García VD Gougeon RD Voilley A Chassagne D 《Journal of agricultural and food chemistry》2006,54(11):3982-3989
The sorption in a model system of aroma compounds of enological interest (mixture of the eight derivatives from guaiacol, 4-ethylphenol, and whiskylactone) onto wood was investigated to assess the influence of wood on the concentration of these volatiles during the aging of wine. To evaluate the influence of the solubility of aroma compounds in sorption phenomena, this parameter was determined for each volatile compound in model wine at 10 and 25 degrees C. The solubility is significantly higher in the model wine than in water and remains constant in the range of temperatures studied, except for guaiacol and vanillin. Kinetic and equilibrium sorptions were investigated. Sorption kinetics showed that the sorption equilibrium for all aroma compounds was reached after 6-7 days. From the study of the individual sorption isotherms, two distinct kinds of sorption behavior were observed depending on the presence or not of an ethylenic para substituent conjugated to the phenyl ring. K(ww) partition coefficients between the wood and the model wine were determined, which exhibited an unusual positive variation with temperature. 相似文献