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101.
Hemophilia B (factor IX deficiency) with concomitant factor XII degradation in a male crossbreed cat
Lutze G Kutschmann K Fürst K Schneppenheim R 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(5-6):255-260
A male cat suffered from a severe haemorrhagic disorder manifesting as deep, partly infected cutaneous haematomas, enhanced and prolonged bleeding after injuries and subsequent lameness at several occasions. Bleeding resulted in severe anaemia with haematocrit falling to as low as 0.10 L/L. Haemophilia B was diagnosed based on factor IX deficiency with a functional residual activity of 5% and factor IX antigen of 8%, respectively. Additionally, factor XII activity was reduced to 32% of normal. The mutation 31217G==>A in exon 8 of the factor IX gene, predicting the amino acid exchange G366R was identified as the cause of moderate factor IX deficiency. This is the first mutation identified in cats with haemophilia B. Treatment was limited to local therapy and palliation, insufficient to prevent lethal outcome due to severe anaemia. 相似文献
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Medium- and long-chain dialkyl 3,3'-thiodipropionate antioxidants such as dioctyl 3,3'-thiodipropionate, didodecyl 3,3'-thiodipropionate, dihexadecyl 3,3'-thiodipropionate, and di-(cis-9-octadecenyl) 3,3'-thiodipropionate were prepared in high yield by lipase-catalyzed esterification and transesterification of 3,3'-thiodipropionic acid and its dimethyl ester, respectively, with the corresponding medium- or long-chain 1-alkanols, i.e., 1-octanol, 1-dodecanol, 1-hexadecanol, and cis-9-octadecen-1-ol, in vacuo (80 kPa) at moderate temperatures (60-80 degrees C) without solvents. Immobilized lipase B from Candida antarctica (Novozym 435) was the most active biocatalyst for the preparation of medium- and long-chain dialkyl 3,3'-thiodipropionates showing enzyme activities up to 1489 units/g, whereas the immobilized lipases from Rhizomucor miehei (Lipozyme RM IM) and Thermomyces lanuginosus (Lipozyme TL IM) were by far less active ( approximately 10 enzyme units/g). Maximum conversions to dialkyl 3,3'-thiodipropionates were as high as 92-98% after 4 h of reaction time. Similarly, dihexadecyl 2,2'-thiodiacetate was prepared in high yield using 2,2'-thiodiacetic acid or diethyl 2,2'-thiodiacetate and 1-hexadecanol as the starting materials and Novozym 435 as the biocatalyst. 相似文献
105.
Andersen CB Ballut L Johansen JS Chamieh H Nielsen KH Oliveira CL Pedersen JS Séraphin B Le Hir H Andersen GR 《Science (New York, N.Y.)》2006,313(5795):1968-1972
In higher eukaryotes, a multiprotein exon junction complex is deposited on spliced messenger RNAs. The complex is organized around a stable core, which serves as a binding platform for numerous factors that influence messenger RNA function. Here, we present the crystal structure of a tetrameric exon junction core complex containing the DEAD-box adenosine triphosphatase (ATPase) eukaryotic initiation factor 4AIII (eIF4AIII) bound to an ATP analog, MAGOH, Y14, a fragment of MLN51, and a polyuracil mRNA mimic. eIF4AIII interacts with the phosphate-ribose backbone of six consecutive nucleotides and prevents part of the bound RNA from being double stranded. The MAGOH and Y14 subunits lock eIF4AIII in a prehydrolysis state, and activation of the ATPase probably requires only modest conformational changes in eIF4AIII motif I. 相似文献
106.
Jhoo JW Freeman JP Heinze TM Moody JD Schnackenberg LK Beger RD Dragull K Tang CS Ang CY 《Journal of agricultural and food chemistry》2006,54(8):3157-3162
Kava (Piper methysticum), a perennial shrub native to the South Pacific islands, has been used to relieve anxiety. Recently, several cases of severe hepatotoxicity have been reported from the consumption of dietary supplements containing kava. It is unclear whether the kava constituents, kavalactones, are responsible for the associated hepatotoxicity. To investigate the key components responsible for the liver toxicity, bioassay-guided fractionation was carried out in this study. Kava roots, leaves, and stem peelings were extracted with methanol, and the resulting residues were subjected to partition with a different polarity of solvents (hexane, ethyl acetate, n-butanol, and water) for evaluation of their cytotoxicity on HepG2 cells based on the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and lactate dehydrogenase and aspartate aminotransferase enzyme leakage assays. Organic solvent fractions displayed a much stronger cytotoxicity than water fractions for all parts of kava. The hexane fraction of the root exhibited stronger cytotoxic effects than fractions of root extracted with other solvents or extracts from the other parts of kava. Further investigations using bioassay-directed isolation and analysis of the hexane fraction indicated that the compound responsible for the cytotoxicity was flavokavain B. The identity of the compound was confirmed by (1)H and (13) C NMR and MS techniques. 相似文献
107.
Kristin Nerlich Frieder Seidl Klaus Mastel Simone Graeff-H?nninger Wilhelm Claupein 《Gesunde Pflanzen》2012,64(3):129-139
The increasing cultivation of energy crops in the last few years may have an impact on changes in the environment, biodiversity and the landscape. Due to a longer rest of soil and reduced application of pesticides, perennial crops such as short rotation coppice (SRC) offer benefits that can have a positive effect on the biodiversity. However, to assess the overall impact of SRC on biodiversity, information on the quality of SRC as a habitat for animals and plants, depending on the woody species over several years and the management is required. In the years 2010 and 2011, the diversity of ground beetles of willow and poplar in SRC were examined using pitfall traps at three sites in southwestern Germany. It was distinguished between species, variety and age of the SRC. At all sites ground beetle diversity was significantly higher in the studied poplar stands than in those of the willows. In addition, significant differences between the varieties could be observed depending on the location and the year of examination. The older stands of the SRC showed in general a higher level of diversity. Due to the different variety preference of ground beetles it is recommended to plant a mixture of varieties. Furthermore, SRC of different ages should be established side by side, as with increasing tree age species of the open area decrease and forest species settle. Overall, SRC offer the potential to increase biodiversity in natural landscapes. 相似文献
108.
Kraemer C Nikseresht N Piatek JO Tsyrulin N Dalla Piazza B Kiefer K Klemke B Rosenbaum TF Aeppli G Gannarelli C Prokes K Podlesnyak A Strässle T Keller L Zaharko O Krämer KW Rønnow HM 《Science (New York, N.Y.)》2012,336(6087):1416-1419
Magnetism has been predicted to occur in systems in which dipolar interactions dominate exchange. We present neutron scattering, specific heat, and magnetic susceptibility data for LiErF(4), establishing it as a model dipolar-coupled antiferromagnet with planar spin-anisotropy and a quantum phase transition in applied field H(c|| = 4.0 ± 0.1 kilo-oersteds. We discovered non-mean-field critical scaling for the classical phase transition at the antiferromagnetic transition temperature that is consistent with the two-dimensional XY/h(4) universality class; in accord with this, the quantum phase transition at H(c) exhibits three-dimensional classical behavior. The effective dimensional reduction may be a consequence of the intrinsic frustrated nature of the dipolar interaction, which strengthens the role of fluctuations. 相似文献
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110.
The European Commission intends to change its animal disease control strategy following the slogan "Prevention is better than cure". Vaccination and diagnostics should play a major role in emergency situations. A policy paper regarding the use of vaccines has been discussed with all Member States and the main aspects were evaluated in a questionnaire. In principle, the majority of Member States are in favour of a future strategy in which vaccination is replacing culling. However, questions regarding the pathogen freedom and the trade of vaccinated animals and animal products from vaccinated animals still remain open. 相似文献