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121.
Rafiquzzaman Muhammad Svenkerud Rolf Strande Anders Hange Jens G. 《Acta veterinaria Scandinavica》1976,17(2):196-209
Four cases of a generalized form of glycogenosis occurring in German Shepherd dogs, all females, are described. Symptoms could be noticed as early as the age of two months and progressed slowly for months. They appeared as dizziness, muscular weakness, and in two of the cases as poor nutritional state. The abdomen became gradually distended. The main lesion seen at postmortem was a greatly increased liver size with some moderate liver fibrosis. Heavy deposits of a granular substance behaving as glycogen in histochemical tests and at electron microscopy were found in the hepatic cells, muscle fibres of the heart, skeletal and smooth muscles, and in nerve and glial cells of the central nervous system. The substance was lying freely dispersed in the cell cytoplasm without any indication of lysosomal storage. The disease of dogs does not seem to be fully comparable with any of the types observed in man, but is probably much related to Type III or Cori's Disease. Structure analysis of the deposits and enzyme investigations have been done and are published (Čeh et al. 1976). 相似文献
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Joran Martijn Anders E. Lind Max E. Schön Ian Spiertz Lina Juzokaite Ignas Bunikis Olga V. Pettersson Thijs J. G. Ettema 《Environmental microbiology》2019,21(7):2485-2498
Amplicon sequencing of the 16S rRNA gene is the predominant method to quantify microbial compositions and to discover novel lineages. However, traditional short amplicons often do not contain enough information to confidently resolve their phylogeny. Here we present a cost-effective protocol that amplifies a large part of the rRNA operon and sequences the amplicons with PacBio technology. We tested our method on a mock community and developed a read-curation pipeline that reduces the overall read error rate to 0.18%. Applying our method on four environmental samples, we captured near full-length rRNA operon amplicons from a large diversity of prokaryotes. The method operated at moderately high-throughput (22286–37,850 raw ccs reads) and generated a large amount of putative novel archaeal 23S rRNA gene sequences compared to the archaeal SILVA database. These long amplicons allowed for higher resolution during taxonomic classification by means of long (∼1000 bp) 16S rRNA gene fragments and for substantially more confident phylogenies by means of combined near full-length 16S and 23S rRNA gene sequences, compared to shorter traditional amplicons (250 bp of the 16S rRNA gene). We recommend our method to those who wish to cost-effectively and confidently estimate the phylogenetic diversity of prokaryotes in environmental samples at high throughput. 相似文献
125.
J Vielkind H Haas-Andela U Vielkind F Anders 《Molecular & general genetics : MGG》1982,185(3):379-389
Summary We report genetic transformation in an intact higher organism, i.e., in xiphophorine fish. The gene to be transferred (Tu) is responsible for the formation of T-melanophores in the platyfish and is involved in the formation of melanomas in platyfish-swordtail hybrids. After injection of Tu-donor DNA into the neural crest region of embryos from Tu-free fish, some of the recipients developed T-melanophores. In a few cases, one or two single T-melanophores were formed during late embryogenesis. In most cases, many T-melanophores developed in young fish and were arranged in several colonies or in a pattern. DNase-degraded Tu-donor DNA, Tu-free fish DNA, as well as DNA from E. coli and adenovirus-2, did not induce T-melanophores. When using DNA from different strains of Tu-donor fish which differed in a regulating gene linked to Tu, the percentages of fish showing T-melanophores paralleled the degree of phenotypic expression of the Tu gene in the DNA donor. The results suggest that the Tu gene has been successfully transferred together with the linked regulating gene.Part of this work has been done by H.H. for her doctoral thesis 相似文献
126.
Marcus Wallgren Martin Lidman Anders Pedersen Kristoffer Br?nnstr?m B. G?ran Karlsson Gerhard Gr?bner 《PloS one》2013,8(4)
The anti-apoptotic B-cell CLL/lymphoma-2 (Bcl-2) protein and its counterpart, the pro-apoptotic Bcl-2-associated X protein (Bax), are key players in the regulation of the mitochondrial pathway of apoptosis. However, how they interact at the mitochondrial outer membrane (MOM) and there determine whether the cell will live or be sentenced to death remains unknown. Competing models have been presented that describe how Bcl-2 inhibits the cell-killing activity of Bax, which is common in treatment-resistant tumors where Bcl-2 is overexpressed. Some studies suggest that Bcl-2 binds directly to and sequesters Bax, while others suggest an indirect process whereby Bcl-2 blocks BH3-only proteins and prevents them from activating Bax. Here we present the results of a biophysical study in which we investigated the putative interaction of solubilized full-length human Bcl-2 with Bax and the scope for incorporating the former into a native-like lipid environment. Far-UV circular dichroism (CD) spectroscopy was used to detect direct Bcl-2-Bax-interactions in the presence of polyoxyethylene-(23)-lauryl-ether (Brij-35) detergent at a level below its critical micelle concentration (CMC). Additional surface plasmon resonance (SPR) measurements confirmed this observation and revealed a high affinity between the Bax and Bcl-2 proteins. Upon formation of this protein-protein complex, Bax also prevented the binding of antimycin A2 (a known inhibitory ligand of Bcl-2) to the Bcl-2 protein, as fluorescence spectroscopy experiments showed. In addition, Bcl-2 was able to form mixed micelles with Triton X-100 solubilized neutral phospholipids in the presence of high concentrations of Brij-35 (above its CMC). Following detergent removal, the integral membrane protein was found to have been fully reconstituted into a native-like membrane environment, as confirmed by ultracentrifugation and subsequent SDS-PAGE experiments. 相似文献
127.
Anders Brunmark 《Luminescence》1989,4(1):219-225
The reaction between p-benzoquinone and H2O2 in slightly alkaline solutions yields three major quinoid products that accumulate in the reaction mixture: (a) 2,3-epoxy-p-benzoquinone, (b) 2-hydroxy-p-benzoquinone and (c) p-benzohydroquinone. The reaction is accompanied by photoemission, probably originating from excited triplet 2-hydroxy-p-benzoquinone. These products originate from hydrogen peroxide and hydroxide nucleophilic addition to the C2?C3 double bond, as well as secondary redox interactions. The hydroxy substituent and the epoxide ring exert a substantial influence on the electronic distribution in the p-benzoquinone molecule leading to a decrease in the half-wave potential, as compared to the parent p-benzoquinone. The generation of electronically excited states is the result of reactions secondary to the nucleophilic additions involving 2-hydroxy-p-benzosemiquinone, H2O2 and hydroxyl radical. The process involves the primary oxidation of 2-hydroxy-p-benzosemiquinone by hydrogen peroxide, followed by oxidation of the semiquinone by hydroxyl radical leading to the formation of the electronically excited quinone. The decay of the excited triplet to the ground state is accompanied by photoemission with maximal intensity at 485–530 nm. Thermodynamic calculations along with an observed increase of photoemission intensity in anaerobiosis point to the triplet (n, π*) multiplicity of the excited state. The efficiency of chemiluminescence could be calculated as 10?8 photons/2-hydroxy-p-benzoquinone molecule formed. Photoemission arising from the p-benzoquinone/H2O2 reaction was inhibited efficiently by addition of GSH to the reaction mixture. This may be due to deactivation of the triplet quinone by a 2-glutathionyl-p-benzohydroquinone adduct, involving thioether α-hydrogen atom-transfer to the triplet ketone. 相似文献
128.
R.L. Merriman A. Swanson M.W. Anders N.E. Sladek 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1978,146(1):85-90
A micromethod for the quantitative analysis of caffeine present in small quantities (100 μl) of whole blood is described. It is based on the gas chromatographic—mass spectrometric analysis of chloroform extracts of biological samples. The method is relatively simple, rapid, specific and sensitive, as little as 20 ng of caffeine can be measured. 相似文献
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Milberg Per Bergman Karl-Olof Glimskär Anders Nilsson Sigrid Tälle Malin 《Plant Ecology》2020,221(7):577-594
Plant Ecology - Management of semi-natural grasslands is essential to retain the characteristic diversity of flora and fauna found in these habitats. To maintain, restore or recreate favourable... 相似文献