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41.

Background

Many dogs suffering from inflammatory bowel disease (IBD) are presented to veterinary clinics. These patients are diagnosed based on a history of chronic gastrointestinal signs and biopsy‐confirmed histopathologic intestinal inflammation. Intestinal intraepithelial lymphocytes (IEL) are part of the first line of defense in the gastrointestinal immune system. Alterations in IEL subsets may play a role in the pathogenesis of IBD.

Hypothesis

The aim of this study was to characterize the phenotypes of IEL in dogs with IBD compared with healthy control dogs.

Animals

Intestinal intraepithelial lymphocytes subpopulations of control dogs (n = 5) obtained from endoscopic biopsies (EB) were compared to those obtained from full thickness biopsies (FTB) on the same day. In addition, the phenotypes of IEL from FTB of control dogs (n = 10) were compared with EB of IBD dogs (n = 10). Each participant was scored clinically using the canine inflammatory bowel disease activity index (CIBDAI), and all samples were graded histopathologically. Three‐color flow cytometry of isolated IEL was performed using monoclonal antibodies against T‐ and B‐lymphocyte subpopulations.

Results

No significant differences in the composition of IEL subpopulations were found in control dogs based on method of biopsy. The IBD dogs had significantly higher CIBDAI and histopathologic scores compared with control dogs and their IEL contained a significantly higher frequency TCRγδ T‐cells.

Conclusions and Clinical Importance

Endoscopic biopsies provide suitable samples for 3‐color flow cytometry when studying canine intestinal IEL and IBD patients show significant changes of major T‐cell subsets compared to healthy control dogs.  相似文献   
42.
Y. M. Yan    S. L. K. Hsam    J. Z. Yu    Y. Jiang  F. J. Zeller 《Plant Breeding》2003,122(2):120-124
Gliadin variation at Gli‐Dt1 and Gli‐Dt2 loci in 198 Aegilops tauschii accessions was studied by acid polyacrylamide gel electrophoresis (A‐PAGE) and capillary electrophoresis (CE). High genetic polymorphisms were found at both gliadin coding loci, revealing a total of 184 and 169 gliadin variants at the Gli‐Dt1 and Gli‐Dt2 loci, respectively. In particular, 12 gliadin blocks encoded by different alleles were apparently expressed and readily identified in six synthetic hexaploids produced by hybridization between Triticum durum and Ae. tauschii accessions. Compared with Ae. tauschii ssp. eusquarrosa, the gliadin profile of the D genome in Ae. tauschii ssp. strangulata more resembles that of T. aestivum, supporting the view that the subspecies strangulata is the most likely progenitor of bread wheat. Capillary electrophoresis analysis showed that the method is capable of separating and characterizing gliadins with speed, in high resolution using small sample amounts, and is well‐suited to detect protein alleles and to identify desirable genotypes in wheat quality improvement.  相似文献   
43.
The wheat-Aegilops speltoides translocation line L501 exhibits a disease response pattern distinctive from that of documented powdery mildew genes after inoculation with differential Blumeria graminis tritici isolates. Results based on cytological C-bandings and monosomic analyses reveal that a dominant resistance gene derived from Ae. speltoides is located on a T1BL·1SS chromosome translocation in this line. The new gene is designated Pm32. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
44.
J. Lutz    E. Limpert    P. Barto&#;  F. J. Zeller 《Plant Breeding》1992,108(1):33-39
Major genes for resistance to powdery mildew were analysed in 24 Czechoslovakian wheat cultivars and, in part, in their parents. For this purpose individual isolates of the pathogen, able to differentiate host lines with known resistance genes, were selected. Eight of nineteen winter wheat cultivars do not possess any major resistance gene. Three cultivars have one and seven have two genes. One cultivar carries a combination of three genes (Pm2, Pm4b, Pm8). The most common resistance genes are Pm4b, Pm5 and Pm8. Pm2 is once combined with Pm6. Only one of five spring cultivars lacked a major resistance gene. Mlk is once present alone and twice combined with Pm5. There is one spring cultivar with a novel combination of three genes: Pm1, Pm5 and another gene needing further characterization. The observations are discussed with additional results of parent lines and further information on pedigrees.  相似文献   
45.
The aim of the present study was to define whether elevated rumen-undegradable protein (RUP) and tannin-rich peanut skin (PS) supplementation would affect animal growth performance, average daily gain (ADG), blood metabolites, carcass traits associated with lipogenic and immune-related gene expressions in meat goats grazing winter wheat (WW). Thirty-six Kiko-crossbreed male goats at approximately 6 months of age were blocked by body weight (BW; 25.6 ± 1.1 kg) and randomly assigned to one of the four treatments with two replicates based on a 2 × 2 factorial design. Diets contained PS replacing alfalfa meal (ALM), without or with RUP supplementation. Both PS and ALM were incorporated into grain mix portion of the diet and pelletized, with remaining diets fed ad libitum of WW forage for a period of 51 days. Lipogenic genes examined included SCD, ACLY, YWHAZ, PPIA and FABP4, while immune-related genes examined included ACTB (as a control gene), H3F3A, PPIA, IRF3, STAT2, HERC3 and IFIT3 antibody genes. The meat goats on PS-pellet-supplemented group with or without RUP supplementation grew 38.5% faster ADG (p < .001) when compared to control-supplemented group. When goats received PS diet, empty body weight, hot carcass, cold carcass, shoulder, hind shank, rack, loin and fat thickness were greater (p < .05) than control diet. Animals on PS-pellet had higher ACLY, YWHAZ, PPIA and FABP4 gene expression (p < .05) when compared to ALM-pellet control, with RUP by PS-pellet interactions (p < .01). Goats receiving additional RUP supplementation had increased (p < .05) STAT2 gene expression, whereas goats receiving PS-pellet supplementation showed increased STAT2 (p < .05) and a tendency to increase IRF3 (p = .07) gene expressions. In conclusion, the addition of PS-pellet or RUP supplementation has the potential to improve ADG and altered selected lipogenic and immune-related gene expressions.  相似文献   
46.

• Introduction   

Atmospheric deposition is an important input of major nutrients into forest ecosystems. The long-term goal of this work was to apply stable isotope methodology to assess atmospheric nutrient deposition in forest systems.  相似文献   
47.
Summary High and low molecular weight glutenin subunit (HMW-GS and LMW-GS) compositions of 270 European spelts, 15 Iranian spelts and 25 bread wheat cultivars were analyzed by one- and two-dimensional gel electrophoresis. The results revealed a total of 22 HMW-GS alleles (4 at Glu-A1, 11 at Glu-B1 and 7 at Glu-D1) and 32 allele combinations among the three Glu-1 loci. Two major genotypes of HMW-GS: 1, 13+16, 2+12 and 1, 6.1+22.1, 2+12 were found to occur in Central European spelt wheat cultivars and landraces at higher frequencies of 35 and 28%, respectively. The Glu-B1 locus displayed the greatest variation and genetic diversity index (H) was 0.69 whereas Glu-A1 and Glu-D1 showed H index values of 0.26 and 0.19, respectively. The dendrogram constructed by HMW and LMW glutenin subunit bands revealed that European spelts form a separated cluster from common wheat suggesting that spelt and common wheat form distinct groups. In addition, all 15 Iranian spelt land variety accessions differed from European spelts and possessed similar HMW-GS alleles to common wheat. Because of a wider polymorphism Central European spelt wheats are an important genetic reserviour for improving common wheat quality. Both authors contributed equally to this work  相似文献   
48.
Summary A total of 59 diploid Aegilops tauschii Coss. (syn. Aegilops sguarrosa auct. non L.) and 39 synthetic hexaploid wheat accessions were evaluated for reaction to Pyrenophora tritici-repentis (Died.) Drechs. in a controlled environment, and classified using a disease rating system based on lesion type. 27 Ae. tauschii and 20 synthetic wheats were found to be resistant to tan spot disease. The overall mean disease ratings of Ae. tauschii and the synthetic wheat lines scored on a scale of 1 (resistant) to 5 (susceptible) were 1.80 and 2.38, respectively. Synthetic wheats generally showed a decrease in resistance, although several lines of synthetic wheat expressed a higher resistance than the diploid parents. Five synthetic wheat lines exhibited higher resistance than the standard resistant common wheat cultivar Red Chief.  相似文献   
49.
50.
The Fagopyrum cymosum complex is a group of wild perennial buckwheats which includes the diploid species F. megaspartanium Q. F. Chen and F. pilus Q. F. Chen as well as the allotetraploid species F. cymosum (Trev.) Meisn. The flavonoid content in leaves and inflorescences of the accessions of the F. cymosum complex native to Guizhou, Yunnan, Sichuan, Hunan, Hubei, and Tibet has been studied by means of the spectrophotometry and high-performance liquid chromatography. The results showed that there are significant differences of flavonoid content among different species, different accessions and different plants. The average flavonoid content of leaves of F. megaspartanium is higher than that of F. pilus and of F. cymosum. The average flavonoid content of inflorescences of F. megaspartanium is higher than that of F. pilus. The results also showed that the flavonoid content in inflorescences was significantly higher than that in leaves, and that they have positive relationships to each other. There is a significant difference of rutin content between leaves and inflorescences, but there is no significant relationship to each other. There is also no significant relationship between leaf rutin contents and leaf flavonoid contents, but significant positive relationship between inflorescence rutin contents and inflorescence flavonoid contents.  相似文献   
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