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41.
Régis Moreau Sadasivam J. Kaushik Konrad Dabrowski 《Fish physiology and biochemistry》1996,15(5):431-438
A study was conducted to evaluate tissue storage and mobilisation of L-ascorbic acid (AA) in the Siberian sturgeon (Acipenser baeri) fed three different experimental diets. The three treatments consisted of a diet devoid of vitamin C (diet A0) and two diets supplemented with equivalent of 300 mg AA kg–1 in the form of either silicone-coated ascorbic acid (diet SC) or of ascorbyl-2-polyphosphate (diet AP). During the first phase (4 months) of the trial, six batches of 130 Siberian sturgeon (initial body weight: 25.5±0.5 g) each were fed one of the three diets in duplicate. During the second phase (3 months), fish from groups SC and AP were switched to diet A0 and those fed diet A0 during the first phase were switched to diet SC. Irrespective of the dietary treatment, growth rates were not significantly different from each other. At the end of phase I, in all tissues studied, total ascorbic acid (TAA) concentrations were higher in Siberian sturgeon fed diet AP than in the other two groups. During phase II, tissue ascorbate depletion was also higher in the AP group than in the other two groups. Transfer of the AA-free diet fed group onto a diet supplemented with 300 mg AA kg–1 (diet SC) led to a slight increase in the TAA concentrations in all tissues. Blood plasma tyrosine concentrations were not significantly different between the three groups. Whole-body collagen levels were affected by dietary AA levels or forms at the end of phase I; the differences were not significant at the end of phase II. Muscle collagen levels were slightly affected. L-Gulonolactone oxidase activity was found in the kidney of Siberian sturgeon, but not in the liver. The ascorbyl-2-polyphosphate appears to be either better utilised by Siberian sturgeon, like in many other teleosts, or more stable than the silicone-coated AA during food processing and storage. Presence of L-gulonolactone oxidase activity in Siberian sturgeon kidney combined with the absence of gross scorbutic signs in AA-free diet fed groups expressing very good growth rates suggested no need of dietary AA byA. baeri. 相似文献
42.
43.
Grain composition of Virginia winter barley and implications for use in feed,food, and biofuels production 总被引:1,自引:0,他引:1
Carl Griffey Wynse Brooks Michael Kurantz Wade Thomason Frank Taylor Don Obert Robert Moreau Rolando Flores Miryeong Sohn Kevin Hicks 《Journal of Cereal Science》2010
Grain compositional components impacting barley (Hordeum vulgare L.) use in food, feed and fuel products, must be combined with improved agronomic traits to produce a commercially viable barley cultivar. Little current information is available on grain composition and variability among winter barley genotypes. This study was conducted to determine the variability among modern hulled and hulless winter barley genotypes in grain composition. Barley types varied significantly in grain and kernel weight, starch, beta-glucan, oil and ash content, but not in protein concentration. Hulless barley had significantly higher grain test weight and starch concentration than hulled and malting types, and significantly higher beta-glucan than malting barley. Hulless barley had significantly lower kernel weights, oil, and ash concentrations than hulled and malting types. Higher starch and lower fiber and ash in grain of hulless barley versus hulled feed or malting type barley are characteristics that increase hulless barley desirability. Selection for high starch concentration among all barley types is feasible and will facilitate development of barley cultivars better suited for use in feed, malt, and ethanol production. 相似文献
44.
Brigitte Moreau J Christophe Vié Philippe Cotellon Ingrund De Thoisy Annie Motard Christian P Raccurt 《Journal of zoo and wildlife medicine》2003,34(2):159-162
Individuals of two porcupine species (Coendou prehensilis and Coendou melanurus) were translocated during the flooding of a forest at a hydroelectric dam site in French Guiana. Blood samples were collected for 11 mo to determine hematologic and serum chemistry reference mean values and ranges and to look for blood parasites. Male C. prehensilis had significantly higher hemoglobin levels, packed cell volumes, and creatinine and potassium values than did females of the same species. Coendou prehensilis had significantly lower amylase levels but higher creatinine, calcium, lactate dehydrogenase, and gamma glutamyl transferase levels than C. melanurus. 相似文献
45.
Maxim E. Zhidkov Moritz Kaune Alexey V. Kantemirov Polina A. Smirnova Pavel V. Spirin Maria A. Sidorova Sergey A. Stadnik Elena Y. Shyrokova Dmitry N. Kaluzhny Oleg A. Tryapkin Tobias Busenbender Jessica Hauschild Tina Rohlfing Vladimir S. Prassolov Carsten Bokemeyer Markus Graefen Gunhild von Amsberg Sergey A. Dyshlovoy 《Marine drugs》2022,20(3)
Marine alkaloid fascaplysin and its derivatives are known to exhibit promising anticancer properties in vitro and in vivo. However, toxicity of these molecules to non-cancer cells was identified as a main limitation for their clinical use. Here, for the very first time, we synthesized a library of fascaplysin derivatives covering all possible substituent introduction sites, i.e., cycles A, C and E of the 12H-pyrido[1-2-a:3,4-b’]diindole system. Their selectivity towards human prostate cancer versus non-cancer cells, as well as the effects on cellular metabolism, membrane integrity, cell cycle progression, apoptosis induction and their ability to intercalate into DNA were investigated. A pronounced selectivity for cancer cells was observed for the family of di- and trisubstituted halogen derivatives (modification of cycles A and E), while a modification of cycle C resulted in a stronger activity in therapy-resistant PC-3 cells. Among others, 3,10-dibromofascaplysin exhibited the highest selectivity, presumably due to the cytostatic effects executed via the targeting of cellular metabolism. Moreover, an introduction of radical substituents at C-9, C-10 or C-10 plus C-3 resulted in a notable reduction in DNA intercalating activity and improved selectivity. Taken together, our research contributes to understanding the structure–activity relationships of fascaplysin alkaloids and defines further directions of the structural optimization. 相似文献
46.
刘璨 Maxim Lobovikov Daniel Murdiyarso Hiroyasu Oka Yeo-Chang Youn Keith Barney Makoto Inoue Hariadi Kartodihardjo Pia Katila Tetsuya Saito Bintang Simangunsong Yasuhiro Yokota 吕金芝 林海燕 《绿色中国(A版)》2005,52(22):33-36
在过去的20年里,亚洲林业经历了引人注目的转型,包括从计划经济到市场经济的转变,从天然林供给木材到人工林供给木材的转变,木材替代品与非木质林产品的增加,地方分权与当地群众的参与,生态时代的发展与生态系统管理。在促进亚洲可持续森林资源管理中,市场工具、社区参与和环境服务都得到了应用。亚洲林业的转型表现出多样化,其森林、社会与环境之间的联系是丰富多彩的。 相似文献
47.
D.Nandris R.Moreau F.Pellegrin H.Chrestin 《热带农业科技》2005,28(3):1-9,F0003
橡胶树排胶障碍是制约全球橡胶种植园发展的主要因素,它是由以下两个不同病症导致的:(1)割面干涸(TPD)-过度割胶引起的可逆生理反应,(2)割面树皮坏死(BN)-由橡胶树根颈韧皮部扩展的不可逆病变。树皮坏死(BN)目前危害了世界大部分胶园,胶园受害严重度取决于橡胶品种、树龄、种植地和种植地区。橡胶树树皮病的多态性一直是一个有争议的问题,通过对许多胶园的调研,该问题最近得到了解决。虽然前期和最近的病原分析不具决定性,但是环境因素却显示出同树皮坏死有联系。在对近期开割的胶园进行流行病调查,发现早期患病胶树地点呈非随机性。这些易发病区主要靠近沼泽地、路旁、风干行、原推土机过道、树林树桩残余地和斜坡缓冲地段的附近区域。在树皮坏死发生区,虽然没有发现与土壤化学因素有明显的关系,但是,土壤物理分析(如透度法)却表明,土壤的较高紧实度常同患病胶树的根系生长较弱有关联。另外,通常在芽接点接合处可以很好地观察到树皮坏死早期症状。通过PMS压力室获得的大量可比生态生理的测量数据显示,患病胶树呈现水分协迫特征,意味着病树树干同其根系存在着一种非理想的维管关系。因此,同土壤紧实度相关的土壤缺水状况、旱季不能满足胶树水分需求的脆弱根系、被扰乱的树液流动和土壤排水等因素的共同作用,被怀疑是诱导树干接芽区树皮坏死(坏死向上扩展到割面) 生理的一个主要外部诱因。在这些协迫的作用下,细胞与分子研究显示,橡胶树生理失调是导致树皮坏死迅速扩展的原因。在这些协迫的作用下,在胶树芽接部位的细胞破裂,释放极具扩散性的高浓度氰化物。在患病胶树的韧皮部生氰和解氰活动的极不协调,以及氰化物的释放,导致其周围的细胞受到毒害。最后, 这样一种多学科的研究方法为由协迫诱导的多因素生理病害研究提供了一个完整的新模式。 相似文献
48.
We present a large-scale molecular phylogeny of the ants (Hymenoptera: Formicidae), based on 4.5 kilobases of sequence data from six gene regions extracted from 139 of the 288 described extant genera, representing 19 of the 20 subfamilies. All but two subfamilies are recovered as monophyletic. Divergence time estimates calibrated by minimum age constraints from 43 fossils indicate that most of the subfamilies representing extant ants arose much earlier than previously proposed but only began to diversify during the Late Cretaceous to Early Eocene. This period also witnessed the rise of angiosperms and most herbivorous insects. 相似文献
49.
Zhang WY Moreau E Yang BZ Li ZQ Hope JC Howard CJ Huang WY Chauvin A 《Research in veterinary science》2006,80(3):299-307
Humoral and cellular immune responses to Fasciola gigantica experimental infection in buffaloes were studied. The results showed that 33.4+/-9.1% of the infection dose was recovered as adult flukes from infected animals at necropsy. Significant differences of weight gain between infected and non-infected buffaloes was observed at 4 MPI (months post-infection). Anti F. gigantica excretory-secretory products (FgESP)-IgG levels increased significantly from 3 WPI (weeks post-infection) and displayed a peak at 13 WPI. Western blot indicated that in FgESP six major bands of 11.5, 19.0, 23.4, 29.8, 47.5 and 53.2kDa were recognized by F. gigantica-infected buffaloes sera after 0 WPI. Eosinophil numbers increased significantly from 3 WPI in F. gigantica-infected buffaloes and displayed a peak at 8 WPI. Peripheral blood mononuclear cells (PBMC) proliferation induced by FgESP increased from 2 WPI with a peak at 5 WPI. IFNgamma secretion by FgESP-stimulated PBMC appeared early from 1 WPI with three peaks at 2, 5 and 8 WPI, respectively. IL-10 production was observed from 2 WPI with two peaks at 4 and 9 WPI, respectively. Our results suggested that buffaloes were highly susceptible to F. gigantica infection, and this susceptibility could be associated with the late and weak cellular immune response in the early phase of infection and the Th0-like response throughout the infection. 相似文献
50.
Bakulin AA Rao A Pavelyev VG van Loosdrecht PH Pshenichnikov MS Niedzialek D Cornil J Beljonne D Friend RH 《Science (New York, N.Y.)》2012,335(6074):1340-1344
The electron-hole pair created via photon absorption in organic photoconversion systems must overcome the Coulomb attraction to achieve long-range charge separation. We show that this process is facilitated through the formation of excited, delocalized band states. In our experiments on organic photovoltaic cells, these states were accessed for a short time (<1 picosecond) via infrared (IR) optical excitation of electron-hole pairs bound at the heterojunction. Atomistic modeling showed that the IR photons promote bound charge pairs to delocalized band states, similar to those formed just after singlet exciton dissociation, which indicates that such states act as the gateway for charge separation. Our results suggest that charge separation in efficient organic photoconversion systems occurs through hot-state charge delocalization rather than energy-gradient-driven intermolecular hopping. 相似文献