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111.
Imaging techniques have been introduced to assess the efficacy and toxicity of developing pharmaceuticals. The purpose of this study was to perform a comprehensive characterization of collagen-induced arthritis (CIA) in rats using micro-computed tomography (micro-CT) and to compare the results with data from conventional pathological examination. Arthritis was induced by collagen in 24 female Wistar rats. Micro-CT and pathological analyses were performed to assess arthritis progression. Micro-CT analysis showed marked joint destruction occurring in a time-dependent manner following collagen administration. Bone volume was significantly decreased in the tibia at weeks 3 and 4 compared to week 0 (p < 0.05 and p < 0.01, respectively). Additionally, percent bone volume was significantly reduced in the tibia at week 4 compared to week 0 (p < 0.05). In contrast, bone surface/bone volume and trabecular separation were significantly increased in the tibia of the animals at week 4 compared to week 0 (p < 0.05). Severe joint destruction with extensive inflammation, erosion of cartilage and bone, and infiltration of inflammatory cells were observed in the knee joints of the collagen-treated rats. Taken together, micro-CT made it possible to quantify CIA lesions and should be performed with pathological examination in rats. 相似文献
112.
Ah Young Kim Hye-Sun Kim Ji-Houn Kang Mhan-Pyo Yang 《Journal of veterinary science (Suw?n-si, Korea)》2015,16(3):333-340
This study was conducted to determine whether serum adipokine concentrations differed between healthy dogs and dogs with diabetes mellitus (DM). To accomplish this, 19 dogs with newly diagnosed DM were compared to 20 otherwise healthy dogs. The serum concentrations of visfatin, leptin, IL-1β, IL-6, IL-18, and TNF-α were significantly higher in diabetic dogs than in healthy dogs, whereas the serum adiponectin concentrations were lower in diabetic dogs. However, there were no significant differences in the IL-10 and resistin levels between groups. The serum leptin concentrations in diabetic dogs with and without concurrent disorders differed significantly. Treatment with insulin induced a significant decrease in IL-6 in diabetic dogs without concurrent disorders. These results show that the clinical diabetic state of dogs could modulate the circulating visfatin and adiponectin concentrations directly, while upregulation of leptin was probably a result of concurrent disorders rather than an effect of persistent hyperglycemia as a result of DM. 相似文献
113.
Rodents are recognized reservoir hosts for many human zoonotic pathogens. The current trends resulting from anthropocene defaunation suggest that in the future they, along with other small mammals, are likely to become the dominant mammals in almost all human‐modified environments. Recent intricate studies on bat‐borne emerging diseases have highlighted that many gaps exist in our understanding of the zoonotic transmission of rodent‐borne pathogens. This has emphasized the need for scientists interested in rodent‐borne diseases to integrate rodent ecology into their analysis of rodent‐borne pathogen transmission in order to identify in more detail the mechanisms of spillover and chains of transmission. Further studies are required to better understand the true impact of rodent abundance and the importance of pathogen sharing and circulation in multi‐host– multi‐pathogen communities. We also need to explore in more depth the roles of generalist and abundant species as the potential links between pathogen‐sharing, co‐infections and disease transmission. 相似文献
114.
115.
Fourier transform mid-infrared (FT-IR) spectroscopy was investigated as a method of analysis for trans fatty acid content of cereal products without the need for prior oil extraction. Spectra were obtained, with an FT-IR spectrometer equipped with an attenuated total reflectance (ATR) device, of ground samples pressed onto the diamond ATR surface, and trans fatty acids were measured by a modification of AOAC Method 996.01. Partial least-squares (PLS) models were developed for the prediction of trans fatty acids in ground samples using several wavenumber selections on the basis of bands related to lipids. The models (n = 79) predicted trans fatty acids in ground samples with standard error of cross-validation (SECV) of 1.10-1.25 (range 0-12.4) % and R2 of 0.85-0.88 and in validation samples (n = 26) with standard error of performance (SEP) of 0.96-1.12 (range 0-12.2) % and r2 of 0.89-0.92, indicating sufficient accuracy for screening. Sample trans fatty acid % was predicted as accurately with the fingerprint region (1500-900 cm(-1)) as with the entire range (4000-650 cm(-1)) indicating, in concert with the regression coefficients, the importance of the isolated trans double bonds at 966 cm(-1) in development of the model. Data is also presented on prediction of trans fatty acids using the spectra of residual oil films on the ATR surface after removing the solid portion of the sample. 相似文献
116.
Choi SW Lee SK Kim EO Oh JH Yoon KS Parris N Hicks KB Moreau RA 《Journal of agricultural and food chemistry》2007,55(10):3920-3925
The antioxidant activity of three major polyamine conjugates, N,N'-dicoumaroyl-putrescine (DCP), N-p-coumaroyl-N'-feruloylputrescine (CFP), and N,N'-diferuloyl-putrescine (DFP) isolated from corn bran, and their related hydroxycinnamic acids, p-coumaric acid and ferulic acid, were evaluated by three antioxidant in vitro assay systems, including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and superoxide and hydroxyl radicals generated by enzymatic and nonenzymatic reactions. Additionally, five phenolic compounds were evaluated for melanogenesis inhibitory activity using mushroom tyrosinase and B16 melanoma cells. Most of the phenolic compounds significantly scavenged DPPH, superoxide, and hydroxyl radicals in a dose-dependent manner. Particularly, DFP showed potent DPPH (IC50 = 38.46 microM) and superoxide (IC50 = 291.62 microM) radical scavenging activities, while DCP exhibited the strongest hydroxyl radical scavenging activity (IC50 = 120.55 microM). CFP also exerted moderate DPPH, superoxide, and hydroxyl radical scavenging activities. Meanwhile, DCP (IC50 = 181.73 microM) showed potent tyrosinase inhibitory activity toward l-tyrosine as the substrate, whereas DFP (IC50 = 733.64 microM) significantly inhibited melanin synthesis in B16 melanoma cells. These current results indicate that these three polyamine conjugates from corn bran may be useful potential sources of natural antioxidants and skin-whitening agents. 相似文献
117.
The acaricidal activity of materials derived from rhizome of Atractylodes ovata (Atractylodes macrocephala) toward adult Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using fabric-circle residual contact and vapor-phase toxicity bioassays. Results were compared with those of the currently used acaricides: benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (Deet). The active principles of A. ovata rhizome were identified as the sesquiterpenoids, atractylenolide III (1) and atractylon (2), by spectroscopic analysis. In fabric-circle residual contact bioassays with adult D. farinae, atractylenolide III (LD50, 103.3 mg/m2) and atractylon (136.2 mg/m2) were five and four times more toxic than Deet and 1.7- and 1.3-fold more active than dibutyl phthalate, respectively, based on 24 h LD50 values. These compounds were less toxic than benzyl benzoate (LD50, 45.8 mg/m2). Against adult D. pteronyssinus, atractylenolide III (LD50, 73.8 mg/m2) and atractylon (72.1 mg/m2) were eight times more active than Deet and 2.5-fold more toxic than dibutyl phthalate. These compounds were slightly less effective than benzyl benzoate (LD50, 46.0 mg/m2). In vapor-phase toxicity tests with both mite species, atractylenolide III and atractylon were effective in closed but not in open containers. These results indicate that the effect of these sesquiterpenoids was largely a result of action in the vapor phase. Naturally occurring atractylenolide III and atractylon merit further study as potential house dust mite control agents or leads because of their great activity as a fumigant. 相似文献
118.
Yoo HH Lee M Chung HJ Lee SK Kim DH 《Journal of agricultural and food chemistry》2007,55(18):7620-7625
The effects of citrus flavonoids on P-glycoprotein (P-gp)-mediated drug efflux were examined in human intestinal Caco-2 cells. The cellular accumulation of rhodamine-123 was measured using 10 citrus flavonoids for preliminary screening. Among the flavonoids tested, diosmin significantly increased the accumulation of rhodamine-123 in Caco-2 cells. In the bidirectional transport of digoxin, diosmin increased the apical-to-basal (A-to-B) transport but decreased the basal-to-apical (B-to-A) transport in both concentration- and time-dependent manners. The digoxin transport ratio (B-A/A-B) was estimated to be 2.3 at a concentration of 50 microM of diosmin, which was significantly lower than the 15.2 found in the control. The apparent Ki values for P(app,A-B) and P(app,B-A) were 16.1 and 5.7 microM, respectively. These results demonstrated that diosmin effectively inhibited the P-gp-mediated efflux in Caco-2 cells. Diosmin is one of the main components in citrus fruits, and the intake of food supplements containing this compound may potentially increase the absorption of drugs able to act as P-gp substrates. The clinical relevance of this interaction should be further evaluated using in vivo experiments. 相似文献
119.
Abdel-Farid IB Kim HK Choi YH Verpoorte R 《Journal of agricultural and food chemistry》2007,55(19):7936-7943
The Brassica has been intensively studied due to the nutritional and beneficial effects. However, many species, varieties, and cultivars of this genus and the resulting large metabolic variation have been obstacles for systematic research of the plant. In order to overcome the problems posed by the biological variation, the metabolomic analysis of various cultivars of Brassica rapa was performed by NMR spectroscopy combined with multivariate data analysis. Discriminating metabolites in different cultivars and development stages were elucidated by diverse 2D-NMR techniques after sorting out different significant signals using (1)H NMR measurements and principal component analysis. Among the elucidated metabolites, several organic and amino acids, carbohydrates, adenine, indole acetic acid (IAA), phenylpropanoids, flavonoids, and glucosinolates were found to be the metabolites contributing to the differentiation between cultivars and age of Brassica rapa. On the basis of these results, the distribution of plant metabolites among different cultivars and development stages of B. rapa is discussed. 相似文献
120.
Kim HY Kang KS Yamabe N Nagai R Yokozawa T 《Journal of agricultural and food chemistry》2007,55(21):8491-8497
We investigated the effects of American ginseng (AG) and heat-processed American ginseng (H-AG) on diabetic renal damage using streptozotocin (STZ)-induced diabetic rats in this study. The diabetic rats showed a loss of body weight gain, and increases in kidney weight, food intake, water intake, and urine volume, whereas the oral administration of H-AG at a dose of 100 mg/kg of body weight per day for 20 days attenuated these diabetes-induced physiological abnormalities. Among the renal function parameters, the elevated urinary protein levels in diabetic control rats were significantly decreased by the AG or H-AG administrations, and the decreased creatinine clearance level was significantly increased in H-AG-administered rats. In addition, the markedly high serum levels of glucose and glycosylated protein in diabetic control rats were significantly decreased by the administration of H-AG, implying that H-AG might prevent the pathogenesis of diabetic complications caused by impaired glucose metabolism and glycosylation of serum proteins. Although no significant ameliorations were shown in overexpressed protein expressions related to diabetic oxidative stress by the AG or H-AG administrations, the accumulation of N (epsilon)-(carboxymethyl)lysine and receptors for advanced glycation endproduct (AGE) expressions were significantly reduced by the administration of H-AG. On the basis of these results, we found that AG and H-AG inhibit AGE accumulation in diabetic rat kidney by their hypoglycemic and renal function ameliorating effects, and this effect was stronger in the H-AG-administered group than in the AG-administered group. These findings indicate that H-AG may have beneficial effect on pathological conditions associated with diabetic nephropathy. 相似文献