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21.
Anthocyanins are potent antioxidants and may be chemoprotective. However, the structure-function relationships are not well understood. The objectives of this study were to compare the chemoprotective properties of anthocyanin-rich extracts (AREs) with variable anthocyanin profiles to understand the relationship between anthocyanin chemical structure and chemoprotective activity, measured as inhibition of colon cancer cell proliferation. Additionally, the chemoprotective interaction of anthocyanins and other phenolics was investigated. AREs with different anthocyanin profiles from purple corn, chokeberry, bilberry, purple carrot, grape, radish, and elderberry were tested for growth inhibition (GI 50) using a human colorectal adenocarcinoma (HT29) cell line. All AREs suppressed HT29 cell growth to various degrees as follows: purple corn (GI 50 approximately 14 microg of cy-3-glu equiv/mL) > chokeberry and bilberry > purple carrot and grape > radish and elderberry (GI 50 > 100 microg of cy-3-glu equiv/mL). Anthocyanins played a major role in AREs' chemoprotection and exerted an additive interaction with the other phenolics present. Statistical analyses suggested that anthocyanin chemical structure affected chemoprotection, with nonacylated monoglycosylated anthocyanins having greater inhibitory effect on HT-29 cell proliferation, whereas anthocyanins with pelargonidin, triglycoside, and/or acylation with cinnamic acid exerted the least effect. These findings should be considered for crop selection and the development of anthocyanin-rich functional foods.  相似文献   
22.
We report three cases of eosinophilic meningitis in young male Rottweiler type dogs in New Zealand. No cause for the disease was identified. There were variable clinical signs referable to central nervous system dysfunction, and a variable response to treatment.  相似文献   
23.
The in vitro and in vivo effects of corticosteroids on peripheral blood lymphocytes (PBL) from ponies were studied. Prednisolone inhibited lymphocyte stimulation by phytohemagglutin (PHA) in a dose-dependent manner, without inducing lysis even at large doses. The PBL from horses heterozygous for the combined immunodeficiency trait responded to corticosteroid treatment the same as did PBL from normal ponies. Removal of the corticosteroid after incubation with PBL from normal ponies partially restored responsiveness of these cells to PHA. Chronic in vivo treatment of ponies with corticosteroids caused a marked decrease in the absolute numbers of circulating lymphocytes. Most remaining lymphocytes had detectable surface immunoglobulin and C3 receptors, suggesting a greater decrease in the T-lymphocyte population. In spite of this, there was little change in the in vitro PHA- or keyhole limpet hemocyanin-sensitized ponies. In general, the corticosteroid effects of lysis, as well as the mitogenic and antigenic responses of PBL from ponies, were similar to those previously reported for human lymphocytes.  相似文献   
24.
Commercially prepared grape (Vitis vinifera), bilberry (Vaccinium myrtillus L.), and chokeberry (Aronia meloncarpa E.) anthocyanin-rich extracts (AREs) were investigated for their potential chemopreventive activity against colon cancer. The growth of colon-cancer-derived HT-29 and nontumorigenic colonic NCM460 cells exposed to semipurified AREs (10-75 microg of monomeric anthocyanin/mL) was monitored for up to 72 h using a sulforhodamine B assay. All extracts inhibited the growth of HT-29 cells, with chokeberry ARE being the most potent inhibitor. HT-29 cell growth was inhibited approximately 50% after 48 h of exposure to 25 microg/mL chokeberry ARE. Most importantly, the growth of NCM460 cells was not inhibited at lower concentrations of all three AREs, illustrating greater growth inhibition of colon cancer, as compared to nontumorigenic colon cells. Extracts were semipurified and characterized by high-pressure liquid chromatography, spectrophotometry, and colorimetry. Grape anthocyanins were the glucosylated derivatives of five different anthocyanidin molecules, with or without p-coumaric acid acylation. Bilberry contained five different anthocyanidins glycosylated with galactose, glucose, and arabinose. Chokeberry anthocyanins were cyanidin derivatives, monoglycosylated mostly with galactose and arabinose. The varying compositions and degrees of growth inhibition suggest that the anthocyanin chemical structure may play an important role in the growth inhibitory activity of commercially available AREs.  相似文献   
25.
A polysaccharide was extracted by warm aqueous phenol from the F-38 strain of mycoplasma which causes contagious caprine pleuropneumonia (CCPP). After acid hydrolysis, the polysaccharide was found to be composed of the neutral sugars glucose, galactose, mannose and fucose and the amino sugars galactosamine and glucosamine. All the sugars were present in approximately equal quantities. Unmodified goat erythrocytes bound the polysaccharide readily and the sensitised cells reacted with antibodies in sera from goats with experimental or natural CCPP. The unique composition of the F-38 polysaccharide and the specific reactivity of polysaccharide-sensitised red cells with antibodies from CCPP infected animals suggests that the polysaccharide should be useful for identification of F-38 organisms and diagnosis of the disease.  相似文献   
26.
Response     
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27.
Effective non-bicarbonate buffering capacity (or buffer value) was measured in white muscle of yellow perch (Perca flavescens) by titrations with mineral acid and base in a carbon-dioxide free, closed system. Yellow perch were collected at three month intervals throughout 1983 from an acidic lake (pH 4.6) and two alkaline lakes (pH 7.8) in northern Wisconsin. Buffering capacity was also determined for white muscle of perch kept in the laboratory under different regimes of temperature and ration. The mean buffering capacity of white muscle from yellow perch taken directly from natural environments ranged from 40.7 ± 3.1 (SD) slykes in March of 1983 to 53.7 ± 2.8 (SD) slykes in July of that year. These changes in buffering capacity were strongly correlated with water temperature. Egg production and thirty-day laboratory starvation produced significant decreases in buffering capacity and increases in the water content of yellow perch muscle. Fed perch in the laboratory had a temperature dependent buffering capacity similar to field caught fish. Buffering capacity of white muscle did not differ between yellow perch from acidic and alkaline lakes. Investigators using buffering capacity as a gauge of species differences in metabolic potential, should be wary of seasonal and reproductive factors that might alter their conclusions.  相似文献   
28.
The osteopontin gene may influence the fertility of water buffaloes because it is a protein present in sperm. The aim of this work was to identify polymorphisms in this gene and associate them with fertility parameters of animals kept under extensive grazing. A total of 306 male buffaloes older than 18 months, from two farms, one in the state of Amapá and the other in the state of Pará, Brazil were used in the study. Seven SNPs were identified in the regions studied. The polymorphisms were in gene positions 1478, 1513 and 1611 in the region 5′upstrem and positions 6690, 6737, 6925 and 6952 in the region amplified in intron 5. The SNPs were associated with the traits, namely scrotal circumference, scrotal volume, sperm motility, sperm concentration and sperm pathology. There were significant SNPs (p < 0.05) for all the traits. The SNP 6690 was significant for scrotal circumference, sperm concentration, sperm motility and sperm pathology and the SNP 6737 for scrotal volume. The genotype AA of SNP 6690 presented the highest averages for scrotal circumference, sperm concentration and motility and the lowest total number of sperm pathologies. For the scrotal volume trait, the animals with the largest volume were correlated with the presence of the genotype GG of SNP 6737. These results indicate a significance of the osteopontin gene as it seems to exert a substantial influence on the semen production traits of male buffaloes.  相似文献   
29.
The cDNA clone of bovine pim-1 has been isolated from phorbol-12-myristate-13-acetate (PMA) and concanavalin A (ConA)-activated peripheral blood lymphocytes (PBLs). The full-length cDNA contains a 411bp 5' untranslated region (5'-UTR), followed by a 939bp coding region and a 3' untranslated region (3'-UTR) that contains 1403bp. Comparison of the bovine pim-1 coding sequence with the human, rat, mouse, frog and zebrafish counterparts reveals 94, 90, 89, 67 and 40% homology at the nucleotide level, respectively. The predicted amino acid sequence of bovine Pim-1 shares 98.7, 97.1, 93.3, 68.8, and 52.4% similarity with the sequences of human, rat, mouse, frog, and zebrafish, respectively. The 5'-UTR of bovine pim-1 shares high sequence similarity to the human and mouse counterparts and is G/C-rich (75%) which may promote a high degree of secondary structure. The 3'-UTR of bovine pim-1 contains two potential polyadenylation sites and an A/T-rich motif which has been shown to decrease the stability of polyA mRNA molecules. Southern blot results indicate that a single copy of the gene exists in the bovine genome. Northern blot results show that PMA stimulation of PBLs increases the expression of the pim-1 mRNA. In addition, examination of Pim-1 protein expression in PBLs stimulated with a variety of mitogens including ConA, PMA, anti-CD3 and purified protein derivative (PPD) from Mycobacterium tuberculosis, reveals two different types of expression patterns during the course of a 24h period of stimulation. ConA and PPD gave a biphasic pattern of expression while PMA and anti-CD3 gave single transient pattern of expression suggesting that expression is controlled by more than one signaling pathway.  相似文献   
30.
The objective of this study was to use a new subtyping technique to determine the identity of five Streptococcus equi isolates from four outbreaks of strangles in Colorado during 2005−2006. All five of the isolates from the four strangles outbreaks in Colorado contained SeM allele 28. This SeM allele is typical of American isolates of S. equi and has previously been linked with strangles outbreaks in Minnesota in 1994 and Kentucky in 1995. Use of the new S. equi strain subtyping method allowed for characterization of recent S. equi isolates associated with outbreaks of strangles in Colorado. To our knowledge, this is the first report of typing of more recent isolates from North America. This approach, however, has been used in situations in the United Kingdom to differentiate the vaccine strain of S. equi from that of the wild type of the bacteria.  相似文献   
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