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51.
ABSTRACT

We evaluated a blend of medium-chain fatty acids (MCFA), organic acids, and a polyphenol antioxidant on gut integrity. Eighty Ross Broilers were exposed to 20–22°C (control – normothermic) or to 35–39.5°C (heat stress) for eight hours a day for a period of 1 or 5 days. Birds were fed a standard diet, or a diet supplemented with the test blend. Thereafter, birds were euthanized, and intestinal sections were excised for morphological, morphometric and gene expression analyses. Blood samples were collected for glucose-6-phosphate dehydrogenase (G6PD), glutathione peroxidase (GSH-Px) activity and trolox equivalent antioxidant capacity (TEAC) determination. Heart and liver tissues were used to quantify the expression of heat shock proteins 60 and 70 (HSP60 and HSP70, respectively) and inhibitor of kappa light chain gene enhancer in B cells alpha (IKBA). The jejunum was the most sensitive intestinal section, where heat stress modulated the expression of HSP70, of the inflammatory markers IKBA, interleukin 8 (IL-8), interferon gamma (IFNγ), and toll-like receptor 4 (TLR4). Moreover, expression of tight junctions (CLDN1, ZO1 and ZO2) and nutrient transporters (PEPT1 and EAAT3) was modulated especially in the jejunum. In conclusion, the feed additive blend protected intestines during heat stress from the decrease in villus height and crypt depth, and from the increase in villus width. Especially in the jejunum, heat stress played an important role by modulating oxidative stress and inflammation, impairing gut integrity and nutrient transport, and such deleterious effects were alleviated by the feed additive blend.

RESEARCH HIGHLIGHTS
  • Jejunum is the most sensitive intestinal segment during heat stress.

  • Heat stress affects the expression of tight junctions and nutrient transporters.

  • Feed management helps to alleviate the disturbances caused by heat stress.

  • A blend of MCFA, organic acids and a polyphenol protects broilers under heat stress.

  相似文献   
52.
The phytochemical contents and medicinal values of Dacroydes edulis and Raphia hookeri exudates were investigated. Phytochemical screening of the plant showed that they contain the presence of bioactive compounds comprising saponins (2.08–3.98mg 100g−1), alkaloids (0.28–0.49 mg 100g−1), tannins (0.47–0.72 mg 100g−1), flavonoids (0.26–0.39 mg 100g−1), and phenolic compounds (0.01–0.05 mg 100g−1). The carbohydrates, lipids and protein content were 77.42–78.90%, 2.02–4.185% and 16.63–18.38% respectively. The exudates are a good source of water soluble vitamins; ascorbic acid (7.04–26.40 mg 100g−1), niacin (3.12–4.00 mg 100g−1), riboflavin (0.14–0.54 mg 100g−1) and thiamine (0.15–0.22 mg 100g−1),). Both plants exudates are good sources of minerals such as Ca, Mg, P, Fe, Zn, Cu and Mn while Cr and Co were trace. These results indicate that exudates can be potential sources of feedstock for the pharmaceutical industry.  相似文献   
53.
Mg^2+对离体灌流内皮素的大鼠心脏功能的影响   总被引:1,自引:0,他引:1  
本实验在离体大鼠心脏灌流模型上,观察到10~(-9)mol/L内皮素灌流引起心肌挛缩,心功能降低,冠脉灌流量减少,以及心肌Ca~(2 )聚积,Mg~(2 )丧失等表现。灌流液含低镁(0.12mmol/L)时内皮素对心脏的上述作用显著增强,而在含高镁(4.8mmol/L)时明显减弱。Mg~(2 )影响内皮素对心脏作用的机制可能与其抑制心肌Ca~(2 )内流有关。实验结果提示避免缺镁,适当补充Mg~(2 )对于防治伴有循环内皮素水平增加的疾病或病理过程中的心脏损伤可能具有临床意义。  相似文献   
54.
Microdissected pancreatic islets of noninbredob/ob-mice were used to study ionic effects on the lanthanum-nondisplaceable45Ca2+ uptake by islet cells. Omission of Mg2+ from the incubation medium had no effect, but the45Ca2+ uptake was increased by omission of Na+ and decreased by omission of K+. Excess Mg2+ (1.2–15 mM) inhibited and excess K+ (4.7–25 mM) stimulated the45Ca2+ uptake in a concentration-dependent manner. Stimulation of45Ca2+ uptake in Na+-deficient islets was associated with an enhancement of the basal insulin release. Total abolishment of glucose-stimulated45Ca2+ uptake in K+-deficient islets did not preclude a significant secretory response to glucose. It is concluded that the lanthanum-nondisplaceable45Ca2+ uptake shows a partial correlation to insulin release.  相似文献   
55.
Summary 42 patients with advanced stage III and IV squamous cell carcinoma of the head and neck were treated with initial cisplatin and bleomycin chemotherapy and subsequent radiotherapy. 39 were evaluable for results, and 3 for toxicity only. 8 patients suffered from stage III and 31 from stage IV tumors, of these 10 with distant metastases. 5 patients underwent later a rescue operation. 27 were previously untreated (= group A) including 2 cases with localized relapses beyond the margins of surgical and/or radiotherapeutic treatment fields. 12 patients had a recurrence within pretreated areas (= group B). The induction chemotherapy alone showed the following results: In group A 4 (15%) CR, 10 (37%) PR, 7 (26%) MR; in group B 3 (25%) PR, 2 (17%) MR. The subsequent radiotherapy mostly consisted of a 65 Gy tumor dose given in 61/2 weeks. The results after completion of the combined modality therapy were: In group A 44% CR, 28% PR; in group B 10% CR and 30% PR. No patient resistant to the initial chemotherapy responded to the radiotherapy. The median survival time of stage III patients was 20 months but only 7 months in stage IV patients. 4 of all live with NED now between 30+ and 41+ months; 1 patient is alive with relapse. All the others are dead after a survival time of max. 32 months, included the 5 with rescue operation. In general, hematologic and renal toxicities were not severe, but nausea and vomiting were the worst tolerated side effects. 1 patient died from septic myocarditis having a WBC nadir of 2000/µl, probably due to additional immunologic deficiency because of inactive liver cirrhosis. The poor results concerning NED survival are discussed. We conclude, that an initial chemotherapy with CDDP and BLM gives good remission effects but its combination with radiotherapy at present fails to produce a NED survival benefit. Further efforts are necessary to improve the CR and the long time survivor rates.
Die Autoren danken folgenden Kollegen für ihre Mitarbeit: Drs. Garbea (HNO), B. Bienko, M. Danker, N. Birke, M. Klessing, K. Lottner, W. Palm  相似文献   
56.
小鼠在纺织噪声104dB(A)环境下,每天暴露8小时,连续2周,脑皮层5-HT,间脑和脑干DA、血浆皮质酮含量都有较明显降低的趋势(0.1>P>0.05),而噪声刺激下服人参复方组小鼠,上述指标均保持在正常范围。上述两组间脑和脑干NA含量变化不明显。  相似文献   
57.
Summary An increased frequency of kidney stone formation is reported in patients with inflammatory bowel disease. In order to investigate its pathogenesis, the concentrations of factors known to enhance calcium oxalate stone formation (oxalate, calcium, uric acid) as well as of inhibitory factors for nephrolithiasis (magnesium, citrate) were determined in the urine of 86 patients with Crohn's disease and compared with those of 53 metabolically healthy controls. Six patients with Crohn's disease already had experienced calcium oxalate nephrolithiasis. Patients with Crohn's disease had significantly higher urinary oxalate and lower magnesium and citrate concentrations. Among all patients magnesium and citrate were significantly lower in those with a positive history of kidney stones. Our results demonstrate that the increased propensity for renal stone formation in patients with Crohn's disease is a result not only of increased urinary oxalate, but also of decreased urinary magnesium and citrate concentrations.Abbreviations CDAI Crohn's disease activity index Dedicated to Professor Dr. N. Zöllner on the occasion of his 65th birthday  相似文献   
58.
不同胎龄母婴间血清前白蛋白与锌、钙、镁水平测定   总被引:1,自引:0,他引:1  
目的 为检测不同孕周母婴间血清前白蛋白 (PA)与锌、钙、镁的水平及它们之间的关系。方法 采用免疫单项扩散法及原子吸收分光光度计火焰法检测了 4 0对早产与 14 8对健康足月母婴血清前白蛋白及锌钙镁的含量。结果  4 0对早产与 14 8对健康足月母亲血清PA均显著高于新生儿脐血PA(P <0 0 0 1) ,血清锌显著低于新生儿 (P <0 0 0 1) ,血清钙早产母亲显著高于早产儿 ,足月母亲则显著低于足月儿。血清镁早产及足月母亲均略低于新生儿 (P >0 0 5 )。各孕周母婴间PA、镁无相关性 ,锌、钙呈正相关。 (相关系数分别为早产 0 39、0 33,足月 0 4 1、0 35 ,(P <0 0 1) ,早产儿脐血血清PA显著低于足月儿 (P <0 0 0 1) ,脐血血清锌低于足月儿 (P <0 0 1) ,脐血血清钙低于足月儿 (P >0 0 5 )。各孕周新生儿脐血PA与自身锌、钙、镁相关分析无相关性。结论 检测各孕周母婴PA、锌、钙、镁的含量 ,可以综合评价早产儿、足月儿的营养状况。  相似文献   
59.
60.
The effect of extracellular magnesium concentration (Mgo) on the upstroke of the action potential was studied in guinea pig ventricular muscle under various K+ concentrations (2.7–19mM). Increased Mgo shifted the steady state inactivation curve of the fast Na channel in the depolarizing direction and this effect was concentration-dependent (0–20mM). Such an effect could explain the Mg-induced increase in maximum rate of rise of the action potential which Späh and Fleckenstein (1979) proposed to be due to a Mg channel.  相似文献   
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