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1.?The present study was conducted to examine the effects of organic extracts from milk thistle (Silybum marianum), turmeric (Curcuma longa), reishi mushroom (Ganoderma lucidum), and shiitake mushroom (Lentinus edodes) on innate immunity and tumor cell viability.

2.?Innate immunity was measured by lymphocyte proliferation and nitric oxide production by macrophages, and the inhibitory effect on tumor cell growth was assessed using a non-radioactive assay. For measuring the cytokine levels in the HD11 macrophages which were treated with extracts of turmeric or shiitake mushroom, the levels of mRNAs for interferon-α (IFN- α), interleukin-1β (IL-1β), IL-6, IL-12, IL-15, IL-18, and tumor necrosis factor superfamily 15 (TNFSF15) were quantified by real time RT-PCR.

3.?In vitro culture of chicken spleen lymphocytes with extracts of milk thistle, turmeric, and shiitake and reishi mushrooms induced significantly higher cell proliferation compared with the untreated control cells. Stimulation of macrophages with extracts of milk thistle and shiitake and reishi mushrooms, but not turmeric, resulted in robust nitric oxide production to levels that were similar with those induced by recombinant chicken interferon-γ. All extracts uniformly inhibited the growth of chicken tumor cells in vitro at the concentration of 6·3 through 100 µg/ml. Finally, the levels of mRNAs encoding IL-1β, IL-6, IL-12, IL-18, and TNFSF15 were enhanced in macrophages that were treated with extracts of turmeric or shiitake mushroom compared with the untreated control.

4.?These results document the immunologically-based enhancement of innate immunity in chickens by extracts of plants and mushrooms with known medicinal properties in vitro. In vivo studies are being planned to delineate the cellular and molecular mechanisms responsible for their mechanism of action.  相似文献   

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马立克氏病病毒致瘤基因meq功能研究的概述   总被引:4,自引:0,他引:4  
马立克氏病病毒 (Marek’sDiseaseVirus,MDV)之众多已得到鉴定的基因中 ,目前有 3个基因即 132 bpr、pp38、meq被认为可能与致瘤相关。其中 ,meq与 132 bpr两个基因是MDV 1所特有 ,已证实 132 bpr的拷贝数与毒株的致弱程度有关 ,pp38则被证实可抑制机体的免疫应答。meq基因由于具有与致瘤基因jun/ fos家族类似的分子结构 ,因此 ,我们有理由认为meq基因在MDV致病、致瘤中可能发挥重要的作用。本课题在国家自然科学基金和广西自然科学基金的资助下 ,历经 5年由三个单位共同攻关…  相似文献   
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Abstract: An 18-month-old male Doberman Pinscher was referred to the Veterinary Medical Teaching Hospital of the College of Veterinary Medicine for an erythemic nodular mass on the right forelimb. The mass was diagnosed as cutaneous lymphoma, based on cytologic examination of a mass aspirate and histopathology. Using immunohistochemistry the neoplastic cells were positive for CD3 but negative for CD79a, E-cadherin, and pancytokeratin, confirming their origin as T lymphocytes. No tumor recurrence was noted 18 months after surgery. To our knowledge, this is the first report of a solitary nodular form of cutaneous lymphoma in a young dog.  相似文献   
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A total of 1002 Escherichia coli strains isolated from pre-weaned pigs with diarrhoea on 1114 swine farms were screened for the presence of the adhesin involved in diffuse adherence (AIDA) gene by polymerase chain reaction (PCR). Escherichia coli isolates that carried AIDA genes were also tested by PCR for the detection of five fimbriae (F4, F5, F6, F18 and F41), heat-stable (STa, STb) and heat-labile (LT) enterotoxin, enteroaggregative E. coli heat-stable enterotoxin 1 (EAST1), and Shiga toxin 2 oedema disease (Stx2e) genes. Twenty-three (2.3%) of the 1002 E. coli isolates carried the gene for AIDA. Among 23 isolates shown to carry genes for AIDA, three carried the AIDA gene as the only shown virulence factor. Other isolates carried other virulence factor genes in addition to AIDA. Four isolates carried genes for at least one of the fimbrial adhesins and enterotoxins. Sixteen isolates carried genes for enterotoxins only. The AIDA may represent an additional virulence determinant in pre-weaned pigs with diarrhoea.  相似文献   
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An experiment was conducted to determine how an E. coil challenge and dietary clays affect the intestinal barrier of pigs. Two groups of 32 pigs (initial BW: 6.9 ± 1.0 kg) were distributed in a 2 x 4 factorial arrangement of a randomized complete block design (2 challenge treatments: sham or E. coil, and 4 dietary treatments: control, 0.3% smectite A, 0.3% smectite B and 0.3% zeolite), with 8 replicates total. Diarrhea score, growth performance, goblet cell size and number, bacterial translocation from intestinal lumen to lymph nodes, intestinal morphology, and relative amounts of sulfo and sialo mucins were measured. The E. coli challenge reduced performance, increased goblet cell size and number in the ileum, increased bacterial translocation from the intestinal lumen to the lymph nodes, and increased ileal crypt depth. One of the clays (smectite A) tended to increase goblet cell size in ileum, which may indicate enhanced protection. In conclusion, E. coli infection degrades intestinal barrier integrity but smectite A may enhance it.  相似文献   
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