排序方式: 共有14条查询结果,搜索用时 15 毫秒
1.
Dietary polyamines promote the growth of azoxymethane-induced aberrant crypt foci in rat colon 总被引:1,自引:1,他引:1
We have examined whether dietary polyamines influence the formation and
initial growth of azoxymethane (AOM)-induced aberrant crypt foci (ACF) in
rat colon. Effects of a combination of dietary polyamines at three dose
levels (putrescine: 50, 280, 740 nmol/g; spermidine: 10, 261, 763 nmol/g;
spermine: 1, 31, 91 nmol/g) in the polyamine-poor AIN-76A diet were studied
in animals in two different experimental situations: animals treated with
AOM alone and animals treated with AOM + difluoromethylornithine (DFMO), a
specific inhibitor of endogenous polyamine synthesis. In both experimental
situations, dietary polyamines enhanced the growth of ACF, expressed as the
number of large ACF (foci with three or more aberrant crypts, ACF > or =
3), whereas the formation of ACF, expressed as the number of ACF, was
apparently not altered. In animals treated with AOM alone, maximal growth
enhancing effect on ACF was nearly obtained with the median level of
dietary polyamine. In rats fed a low polyamine diet, basic AIN-76A, DFMO
reduced the growth of AOM-induced ACF by 83%. This inhibitory effect of
DFMO was counteracted by dietary polyamines in a dose- dependent manner,
and it was abolished at the highest level of polyamines. In conclusion, it
was demonstrated that dietary polyamines are able to enhance the growth of
AOM-induced ACF. Further, dietary polyamines reversed the DFMO-caused
inhibition of ACF growth, probably by compensating for the DFMO-reduced
endogenous polyamine synthesis.
相似文献
2.
3.
I. VANČOVÁ V. HAJNICKÁ M. SLOVÁK P. KOCÁKOVÁ G. C. PAESEN P. A. NUTTALL 《Parasite immunology》2010,32(6):460-463
Ticks exploit many evasion mechanisms to circumvent the immune control of their hosts including subversion of the communication language between cells of the immune system provided by chemokines and other cytokines. One subversive molecule secreted in the saliva of Rhipicephalus sanguineus is Evasin‐3, a structurally unique 7 kDa protein that selectively binds the neutrophil chemoattractants, CXCL8 and (with lower affinity) CXCL1. We compared anti‐human CXCL8 and anti‐mouse CXCL1/KC activities in salivary gland extracts prepared from adult Amblyomma variegatum, Rhipicephalus appendiculatus and Dermacentor reticulatus ticks during blood‐feeding. Both anti‐CXCL8 activity and anti‐CXCL1 activity were detected in all species and in both adult females and males, with consistently higher activity levels against CXCL8. These results suggest that Evasin‐3‐like activity is common amongst metastriate ixodid tick species, and provide further evidence of the importance to ticks in controlling neutrophils during blood‐feeding. As such, Evasin‐3 offers a new target for anti‐tick vaccine development. 相似文献
4.
Olga V Ochenashko Yurii V Nikitchenko Nataliya A Volkova Svetlana P Mazur Alexander Y Somov Barry J Fuller Alexander Y Petrenko 《Journal of gastroenterology and hepatology》2008,23(7PT2):e275-e282
Background and Aim: Chronic liver failure results in the decrease of the number of functioning hepatocytes. It dictates the necessity of using exogenous viable cells or/and agents that can stimulate hepatic regenerative processes. Fetal liver contains both hepatic and hematopoietic stem cells with high proliferative potential, which may replace damaged cells. Also, immature cells produce fetal-specific factors which may support the injured liver. Our aim was to test the ability of human fetal liver cells and cell-free fetal-specific factors of non-hepatic origin to stimulate recovery processes in an experimental model of carbon tetrachloride–induced cirrhosis in rats.
Methods: Cirrhotic rats were intrasplenically injected with fetal liver cells (1 × 107 cells/0.3 mL medium) or cell-free fetal-specific factors (0.3 mL/1 mg protein). Control groups received medium alone. Serum indexes, hepatic functions, and morphology were evaluated for 15 days.
Result: Human fetal liver cell transplantation was shown to abrogate the mortality of cirrhotic animals, to improve serum markers, and to restore liver mitochondrial function and detoxification. Morphological patterns of liver recovery were observed by histology. In comparison, an injection of fetal-specific factors produced similar functional recovery, whilst a more limited liver regeneration was observed by histology.
Conclusions: The positive effects of fetal liver cell and cell-free fetal-specific factors in experimental cirrhosis may result from the presence of stage-specific factors activating hepatocellular repair. 相似文献
Methods: Cirrhotic rats were intrasplenically injected with fetal liver cells (1 × 10
Result: Human fetal liver cell transplantation was shown to abrogate the mortality of cirrhotic animals, to improve serum markers, and to restore liver mitochondrial function and detoxification. Morphological patterns of liver recovery were observed by histology. In comparison, an injection of fetal-specific factors produced similar functional recovery, whilst a more limited liver regeneration was observed by histology.
Conclusions: The positive effects of fetal liver cell and cell-free fetal-specific factors in experimental cirrhosis may result from the presence of stage-specific factors activating hepatocellular repair. 相似文献
5.
6.
7.
目的了解β地中海贫血(地贫)CD41-42(-TCTT)杂合子(β41-42杂合子)复合缺失型α地贫双重杂合子在本地区β41-42杂合子个体中的检出情况及其临床血液学表现.方法分别采用单管多重PCR与反向点杂交法检测缺失型α地贫与β地贫基因,常规进行血细胞分析及其它地贫筛查试验.结果 144例β41-42杂合子有8例同时复合缺失型α地贫杂合子,其中7例(4.9%)携带有α地贫1基因(αα/--SEA),1例(0.69%)携带有缺失型HbH基因(-α3.7/--SEA).7例复合α地贫1患者的MCV均都高于另外136例单纯的β41-42杂合子的MCV平均值(63.53fl); 而对携带有HbH基因的样本进行pH8.6与6.5的血红蛋白电泳时都无法找到HbH区带.结论诊断β41-42杂合子复合α地贫双重杂合子的患者时,如只依赖其临床表现和常规的实验室检查结果作为筛查诊断的指标,容易会出现有病患的α或β地贫基因漏诊的情况. 相似文献
8.
Index
SOFFCO, Montpellier 31 mai–2 juin 2012 Index des auteurs 相似文献9.
10.
V. I. Grishchenko Yu. V. Nikitchenko O. V. Ochenashko A. Yu. Petrenko V. V. Bondar' V. N. Dzyuba 《Bulletin of experimental biology and medicine》2001,132(4):950-952
We studied the effect of transplantation of fetal liver cells and postnuclear cytoplasmic fraction from human fetal soft tissues on the prooxidant-antioxidant equilibrium in the liver and blood of rats after partial hepatectomy. The preparations increased antioxidant activity and decreased the intensity of lipid peroxidation, which probably contributes to their therapeutic effects. 相似文献