Evaluation of the drug sensitivity and expression of 16 drug resistance-related genes in canine histiocytic sarcoma cell lines     

Hajime ASADA  Hirotaka TOMIYASU  Yuko GOTO-KOSHINO  Yasuhito FUJINO  Koichi OHNO  Hajime TSUJIMOTO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(6):677-684

Canine histiocytic sarcoma (HS) is an aggressive tumor type originating from histiocytic cell lineages. This disease is characterized by poor response to chemotherapy and short survival time. Therefore, it is of critical importance to identify and develop effective antitumor drugs against HS. The objectives of this study were to examine the drug sensitivities of 10 antitumor drugs. Using a real-time RT-PCR system, the mRNA expression levels of 16 genes related to drug resistance in 4 canine HS cell lines established from dogs with disseminated HS were determined and compared to 2 canine lymphoma cell lines (B-cell and T-cell). These 4 canine HS cell lines showed sensitivities toward microtubule inhibitors (vincristine, vinblastine and paclitaxel), comparable to those in the canine B-cell lymphoma cell line. Moreover, it was shown that P-gp in the HS cell lines used in this study did not have enough function to efflux its substrate. Sensitivities to melphalan, nimustine, methotrexate, cytarabine, doxorubicin and etoposide were lower in the 4 HS cell lines than in the 2 canine lymphoma cell lines. The data obtained in this study using cultured cell lines could prove helpful in the developing of advanced and effective chemotherapies for treating dogs that are suffering from HS.  相似文献   

Dietary lipid level affects fatty acid composition and hydrolase activities of intestinal brush border membrane in seabass   总被引：2，自引：0，他引：2  

C.L. Cahu  J.L. Zambonino Infante  G. Corraze  D. Coves 《Fish physiology and biochemistry》2000,23(2):165-172

Triplicate groups of juvenile seabass (initial weight of 241 g) were fed during 13 weeks three isonitrogenous experimental diets containing different lipid levels, 12% (LL group), 21% (ML group) and 30% (HL group). At the end of the experiment, fish weight gain was similar among the 3 dietary groups. Intestinal brush border membranes were purified for each dietary group; one part of the brush border fraction was dedicated to enzyme assays, the remaining fraction being used for lipid extraction followed by fatty acid analysis. The fatty acid composition of the brush border membrane differed among the 3 groups, although the 3 experimental diets had the same fatty acid composition. The increase in dietary lipid level resulted in a lowering in (n-3) polyunsaturated fatty acid (PUFA) paralleled with an increase in monounsaturated fatty acid. A significant reduction in the brush border enzyme activities, namely alkaline phosphatase, aminopeptidase N, -glutamyl transpeptidase and maltase, was also observed with the elevation of the dietary lipid level. The change in activity of intestinal digestive enzymes, which are membrane-bound proteins, could be attributed to the modification of fatty acid composition and fluidity of the brush border membranes (BBM). Such lowering in PUFA and increase in monounsaturated fatty acid in BBM, concomitant with a decline in membrane enzymatic activity, has been described as a malnutrition indicator in mammals. It raises the question of possible disorders of gut functions in fish fed increasing lipid levels.  相似文献   

Effects of aromatase inhibitors on reproduction in male three-spined sticklebacks, Gasterosteus aculeatus, exposed to long and short photoperiods     

C. Bornestaf  E. Antonopoulou  I. Mayer  B. Borg 《Fish physiology and biochemistry》1997,16(5):419-423

Three-spined stickleback Gasterosteus aculeatus, males were implanted with Silastic capsules filled with different aromatase inhibitors; 1,4,6-androstatriene-3,17-dione or the non-steroidal CGS16949 A, 4-(5,6,7,8-tetrahydrimidazol [1,5-a]pyridin-5-yl) benzonitrile monohydrochloride or empty capsules. The fish were then exposed to long or short photoperiod. Under the long photoperiod most fish in all treatments displayed a hypertrophied kidney (a secondary sexual character in sticklebacks) and completed, quiescent spermatogenesis, similar as in the natural spawning period. Under the short photoperiod the controls had unstimulated kidneys and an active spermatogenesis, whereas the males implanted with both aromatase inhibitors had stimulated kidneys, though not to the extent as in the long photoperiod, and completed, quiescent spermatogenesis. These findings suggest that aromatization is of importance for the inhibitory effects of short photoperiod on reproduction in the stickleback. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Breaking seasonal limitation: year-round sporogenesis in the brown alga Laminaria saccharina by blocking the transport of putative sporulation inhibitors     

Shao Jun Pang  Klaus Lüning   《Aquaculture (Amsterdam, Netherlands)》2004,240(1-4):531-541

Year-round induction of sporogenesis of Laminaria saccharina was performed by mechanically blocking the transport of the putative sporulation inhibitors produced by the blade meristem and culturing the plants in constant short days. Sporogenesis was successfully induced by removal of the blade meristem, either by cultivating distal blade fragments or by performing a transverse cut in the frond. The earliest sorus formation after artificial induction was 10 days. The age of the sporophytes used for induction was 6–11 months or 2 years in tank-grown or field-collected sporophytes, respectively. Zoospores were successfully released in all cases. Thus, by year-round artificial induction of sporogenesis, (1) sporeling production of L. saccharina and thereafter sporophyte cultivation could be achieved without seasonal limitation, and (2) the life cycle of L. saccharina (from spore to spore) could be completed within 8 months under controlled conditions.  相似文献   

Effect of idazoxan on permeability of inflammatory blood-brain barrier model in vitro     

WANG Xin-shi  ZHU Pan  ZHU Zhen-guo  XIA Nian-ge  LI Jia  ZHENG Rong-yuan 《园艺学报》2015,31(4):669-674

AIM: To study the effect of idazoxan on the permeability of inflammatory blood-brain barrier (BBB) model in vitro and the expression of tight junction protein ZO-1.METHODS: In vitro BBB model was established by murine brain endothelial cell line bEnd.3 incubated for 7 d. The cells were treated with TNF-α (10 nmol/L) for additional 24 h to establish the inflammatory BBB model, which was pretreated with IDA at doses of 50, 100 and 200 μmol/L, respectively. The permeability was measured using fluorescein isothiocyanate-conjugated dextran (FD-40, MW 40,000), the expression of ZO-1 was detected by Western blot analysis, the distribution of ZO-1 was observed by immunofluorescence, and the mRNA expression of MMP-9/TIMP-1 was measured by RT-PCR.RESULTS: After incubated for 7 d, b.End3 cells converged to be confluent monolayer with low permeability. The inflammatory BBB model induced by TNF-α treatment displayed much higher permeability with decreased expression of tight junction protein ZO-1, destroyed distribution of ZO-1 and increased mRNA expression of MMP-9. When pretreated with IDA, the permeability was greatly decreased, the expression of ZO-1 was greatly increased, the abnormal distribution of ZO-1 was greatly ameliorated and the mRNA expression of MMP-9 was obviously reduced. The effect was most significant in IDA (200 μmol/L)-pretreated group (P<0.01).CONCLUSION: IDA directly acts on brain endothelial cells to reduce the expression of MMP-9, increase the expression of tight junction protein ZO-1 and ameliorate the destroyed distribution of ZO-1 in the inflammatory BBB, thus reversing the abnormally elevated permeability in a inflammatory BBB model in vitro induced by TNF-α.  相似文献   

Introduction of new traits into cotton through genetic engineering: insect resistance as example   总被引：1，自引：0，他引：1  

C. Pannetier  M. Giband  P. Couzi  V. Le Tan  M. Mazier  J. Tourneur  B. Hau 《Euphytica》1997,96(1):163-166

The main goal of gene transfer into cotton is the development of insect-resistant varieties. The stakes are important since cotton protection against insects uses almost 24% of the world's chemical insecticides market, which is not without consequences on the environment. The first approach was to introduce and express in the cotton genome, genes from the bacterium Bacillus thuringiensis (B.t.) which produces entomopathogenic toxins. The development of an efficient Agrobacterium tumefaciens mediated transformation system was the first step. The expression of B.t. genes was studied and synthetic genes more adapted to a plant genome have been constructed. Studies on their expression in cotton is underway. The second focus was to develop strategies that would minimize the risks of inducing insect resistance. The main approach is to associate several genes coding for entomopathogenic proteins with different modes of action. Genes encoding protease inhibitors were chosen. One possibility is to associate a B.t. gene and a gene encoding a protease inhibitor. Several protease inhibitors were tested in artificial diets on major pests of cotton. The corresponding genes have been introduced into the cotton genome. These various orientations of the research program will be presented. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

Effective nitrification inhibitors may improve fertilizer recovery in irrigated cotton   总被引：6，自引：0，他引：6  

I. Rochester  G. Constable  P. Saffigna 《Biology and Fertility of Soils》1996,23(1):1-6

N fertilizer is often poorly recovered in irrigated cotton production, due to N loss through denitrification. We researched the ability of inhibitors to delay nitrition and reduce the availability of NO₃ ^- to denitrifying microorganisms and thus improve N fertilizer recovery, 2-Ethynylpyridine, etridiazole, and nitrapyrin proved highly effective nitrification inhibitors, although nitrification was evident several weeks after their application. CaC₂ was relatively ineffective, even when wax-coated to prolong the evolution of C₂H₂. Phenylacetylene and ethynylcyclohexanol were also ineffective, despite having a chemical structure similar to 2-ethynylpyridine. A strong association was identified between each compound's ability to inhibit nitrification and its capacity to improve N fertilizer recovery. In one experiment, N fertilizer recovery was increased by 50% with 2-ethynylpyridine, etridiazole, or nitrapyrin application, from 33% without inhibitors. The inhibitors had little effect on fertilizer recovery where N losses were relatively small. 3-Methyl pyrazole significantly increased N uptake and lint yield, but the nitrification inhibitors had no significant effect on N uptake or on yield in two of the three of the cotton crops. A laboratory study confirmed that nitrification inhibitor effectiveness declined in the order 2-ethynylpyridine>etridiazole>nitrapyrin>3-methyl pyrazole>phenylacetylene>CaC₂>ethynylcyclohexanolThis research was conducted at Australian Cotton Research Institute, CSIRO Division of Plant Industry, Locked Bag 59, Narrabri, NSW 2390, Australia  相似文献   

Soil microbial functional diversity response following nematocide and biocide amendments in a desert ecosystem     

Tamar Kaffe-Abramovich 《Soil biology & biochemistry》2006,38(7):1966-1976

The aim of the current study was to gain a better understanding of the changes that occur in soil microbial community and in its functional diversity as a result of the use of nematocide and biocide inhibitors in natural ecosystems. Both inhibitors are known to have a great effect on the nematode community and total biota, playing an important role in soil food web and biota interactions. The experiment was set up in the Negev Desert using sixteen 1×1 m soil plots, to which two chemical inhibitors were applied: (a) a biocide, to eliminate the whole biotic community; and (b) a nematocide, to eliminate the nematode community in soil. In addition, water treatment was applied to the same soil plots, while untreated soil plots were used as control. Microbial functional diversity, together with abiotic parameters such as soil moisture and total organic carbon, was tested monthly in soil samples collected from the 0-10 and 10-20 cm soil layers. The results of the abiotic parameters showed similar patterns in the two soil layers regardless of the inhibitor treatments. An increase in soil water content followed rainfall patterns. Total organic carbon was low during the wet season and increased during the dry seasons. The Shannon-Weaver index value for microbial functional diversity was found to increase in spring after the wet season in both soil layers. In the upper soil layer, an increase was observed both in the inhibitor and water treatments. However, the increase in the water treatment lasted longer compared to the increase observed in the inhibitor-treated soil plots. In the 10-20 cm soil layer, a different pattern was observed: an increase in microbial functional diversity was observed in the inhibitor-treated soil plots, while an increase in the water-treated soil plots was seen at a later stage. Principal Component Analysis was also conducted, revealing different patterns between inhibitors and water treatments on both a temporal scale, when changes from a homogeneous to heterogeneous consumption pattern were observed, and in the nature of communities that proliferate in the soil. Differences were also observed in the microbial community between the upper 0-10 and the lower 10-20 cm soil layers, where an opposite pattern of substrate consumption was observed. This study emphasizes the important role the biotic component plays in the soil of an arid climate, studying the long-term effects of key species elimination on the microbial community in desert soil.  相似文献   

Measurement of coupled nitrification-denitrification in paddy fields affected by Terrazole,a nitrification inhibitor   总被引：2，自引：0，他引：2  

David?CarrascoEmail author  Eduardo?Fernández-Valiente  Yoanna?Ariosa  Antonio?Quesada 《Biology and Fertility of Soils》2004,39(3):186-192

Coupled nitrification-denitrification and potential denitrification were measured as ¹⁵N₂O and ¹⁵N₂ evolution rates in ammonium sulphate-treated rice soils with or without Terrazole [5-ethoxy-3 (trichloromethyl) 1,2,3 Thiadizole] under laboratory and field conditions. The greatest coupled nitrification-denitrification activity was found after drying and rewetting the soil, with maximum values of 322 ng N cm^–2 h^–1 in the laboratory and 90.8 ng N cm^–2 h^–1 in the field. These ¹⁵N₂O + ¹⁵N₂ evolution rates were about 10 times lower than potential denitrification in these soils. These results and the observed decrease in ¹⁵N₂O + ¹⁵N₂ evolution rate in soils treated with Terrazole (60% under laboratory conditions and 52% under field conditions) indicate that denitrification was limited by coupled nitrification-denitrification activity. Oxygen and previous addition of ammonium sulphate appear to control the rate of ¹⁵N₂O + ¹⁵N₂ evolution in ammonium sulphate-fertilised soils.  相似文献   

反刍动物脲酶抑制剂的研究进展   总被引：5，自引：0，他引：5  

李杰  葛蔚 《东北农业大学学报》2004,35(1):119-122

尿素作为非蛋白氮饲料直接饲喂动物 ,在瘤胃中分解速度快于微生物利用速度 ,这不仅降低尿素利用效率 ,而且容易造成氨中毒。脲酶抑制剂可以降低尿素的分解速度 ,提高尿素利用效率。文章就目前国内外各种瘤胃脲酶抑制剂对动物瘤胃尿素分解速度、氨浓度、营养物质利用及对动物生产性能的影响进行了综述。  相似文献