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171.
Friedrich W. Keppeler Eduardo R. Cunha Kirk O. Winemiller 《Zeitschrift fur angewandte Ichthyologie》2020,36(1):121-124
Fin clips have been proposed as a non-lethal and non-invasive alternative to dorsal muscle samples in stable isotope analysis. However, potential differences in elemental composition and turnover rates can bias inferences when different tissues are combined. Here, we tested the average difference and correlation of the isotopic signature of δ13C and δ15N between muscle and fin samples in two arge-bodied fishes: Longnose Gar (Lepisosteus osseus) and Smallmouth Buffalo (Ictiobus bubalus). We found that δ15N signatures of muscle and fin tissues were strongly and positively correlated for both species, although the muscle tissue for Smallmouth Buffalo was slightly more enriched in δ15N. δ13C signatures of both tissues were significatively different and not strongly correlated for Longnose Gar, but similar and strongly correlated for Smallmouth Buffalo. Our results suggest that fin and muscle tissue can be combined for analyses of δ15N, but correction for higher enrichment of muscle tissue may be necessary for Smallmouth Buffalo. Conversely, combining fin and muscle tissue for analysis of δ13C requires more caution due to their weaker correlation and dependence of species identity. 相似文献
172.
Hydrobiologia - The littoral zones of many Central European lakes are severely altered by lake-side retaining walls. These are suspected to impair littoral biota due to the reflection of incoming... 相似文献
173.
Margret Rave-Fränk Ihtzaz Ahmed Malik Hans Christiansen Naila Naz Sadaf Sultan Ahmad Amanzada Martina Blaschke Silke Cameron Shakil Ahmad Clemens Friedrich Hess Giuliano Ramadori Federico Moriconi 《Radiation and environmental biophysics》2013,52(3):321-338
The liver is considered a radiosensitive organ. However, in rats, high single-dose irradiation (HDI) showed only mild effects. Consequences of fractionated irradiation (FI) in such an animal model have not been studied so far. Rats were exposed to selective liver FI (total dose 60 Gy, 2 Gy/day) or HDI (25 Gy) and were killed three months after the end of irradiation. To study acute effects, HDI-treated rats were additionally killed at several time points between 1 and 48 h. Three months after irradiation, no differences between FI and HDI treatment were found for macroscopically detectable small “scars” on the liver surface and for an increased number of neutrophil granulocytes distributed in the portal fields and through the liver parenchyma. As well, no changes in HE-stained tissues or clear signs of fibrosis were found around the portal vessels. Differences were seen for the number of bile ducts being increased in FI- but not in HDI-treated livers. Serum levels indicative of liver damage were determined for alkaline phosphatase (AP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyltransferase (γGT) and lactate dehydrogenase (LDH). A significant increase of AP was detected only after FI while HDI led to the significant increases of AST and LDH serum levels. By performing RT-PCR, we detected up-regulation of matrix metalloproteinases, MMP-2, MMP-9, MMP-14, and of their inhibitors, TIMP-1, TIMP-2 and TIMP-3, shortly after HDI, but not at 3 month after FI or HDI. Overall, we saw punctual differences after FI and HDI, and a diffuse formation of small scars at the liver surface. Lack of “provisional clot”-formation and absence of recruitment of mononuclear phagocytes could be one explanation for scar formation as incomplete repair response to irradiation. 相似文献
174.
Fen-Long Li Friedrich J. Zeller Kai-Feng Huang Tao-Xiong Shi Qing-Fu Chen 《Plant Systematics and Evolution》2013,299(9):1679-1691
Fluorescent chromosome in situ PCR method plays an important role in many fields of biology and can be used for determining physical maps, chromosomal structures and phylogeny. In the present study, improvements are made to fluorescent chromosome in situ PCR protocol by incorporating the use of SYBR Green I. All the complex procedures in this method have been removed, including the fixing of PCR products, the linkage step of antigen and antibody and the necessary detection the fluorescence signal. This new method is useful for the types of studies mentioned above. As an example, this improved technique was performed using primers for the 16S rDNA, 4.5S rDNA and psbA chloroplast DNA (cpDNA) genes to investigate the phylogeny of buckwheat, the introgression of cpDNA genes into nuclear genome and the chromosomal location of these genes for the construction of a physical map. The results showed that the 16S rDNA, 4.5S rDNA and psbA cpDNA genetic markers were found with different abundances and physical distributions in the nuclear genomes of the seven buckwheat species (10 accessions in total) under investigation. These data were used to confirm the phylogeny of these buckwheat species by constructing a phylogenetic tree. 相似文献
175.
176.
Chandramohan Chitraju Martin Tr?tzmüller Jürgen Hartler Heimo Wolinski Gerhard G. Thallinger Guenter Haemmerle Rudolf Zechner Robert Zimmermann Harald C. K?feler Friedrich Spener 《Journal of lipid research》2013,54(8):2185-2194
We showed earlier that nutritional stress like starvation or high-fat diet resulted in phenotypic changes in the lipidomes of hepatocyte lipid droplets (LDs), representative for the pathophysiological status of the mouse model. Here we extend our former study by adding genetic stress due to knockout (KO) of adipocyte triglyceride lipase (ATGL), the rate limiting enzyme in LD lipolysis. An intervention trial for 6 weeks with male wild-type (WT) and ATGL-KO mice was carried out; both genotypes were fed lab chow or were exposed to short-time starvation. Isolated LDs were analyzed by LC-MS/MS. Triacylglycerol, diacylglycerol, and phosphatidylcholine lipidomes, in that order, provided the best phenotypic signatures characteristic for respective stresses applied to the animals. This was evidenced at lipid species level by principal component analysis, calculation of average values for chain-lengths and numbers of double bonds, and by visualization in heat maps. Structural backgrounds for analyses and metabolic relationships were elaborated at lipid molecular species level. Relating our lipidomic data to nonalcoholic fatty liver diseases of nutritional and genetic etiologies with or without accompanying insulin resistance, phenotypic distinction in hepatocyte LDs dependent on insulin status emerged. Taken together, lipidomes of hepatocyte LDs are sensitive responders to nutritional and genetic stress. 相似文献
177.
Ismail Hassan Ismail Darin McDonald Hilmar Strickfaden Zhizhong Xu Michael J. Hendzel 《The Journal of biological chemistry》2013,288(37):26944-26954
Polycomb-repressive complex 1 (PRC1)-mediated histone ubiquitylation plays an important role in aberrant gene silencing in human cancers and is a potential target for cancer therapy. Here we show that 2-pyridine-3-yl-methylene-indan-1,3-dione (PRT4165) is a potent inhibitor of PRC1-mediated H2A ubiquitylation in vivo and in vitro. The drug also inhibits the accumulation of all detectable ubiquitin at sites of DNA double-strand breaks (DSBs), the retention of several DNA damage response proteins in foci that form around DSBs, and the repair of the DSBs. In vitro E3 ubiquitin ligase activity assays revealed that PRT4165 inhibits both RNF2 and RING 1A, which are partially redundant paralogues that together account for the E3 ubiquitin ligase activity found in PRC1 complexes, but not RNF8 nor RNF168. Because ubiquitylation is completely inhibited despite the efficient recruitment of RNF8 to DSBs, our results suggest that PRC1-mediated monoubiquitylation is required for subsequent RNF8- and/or RNF168-mediated polyubiquitylation. Our results demonstrate the unique feature of PRT4165 as a novel chromatin-remodeling compound and provide a new tool for the inhibition of ubiquitylation signaling at DNA double-strand breaks. 相似文献
178.
Justin M. Greene Jennifer J. Lhost Paul J. Hines Matthew Scarlotta Max Harris Benjamin J. Burwitz Melisa L. Budde Dawn M. Dudley Ngoc Pham Brian Cain Caitlin E. Mac Nair Madelyn K. Weiker Shelby L. O'Connor Thomas C. Friedrich David H. O'Connor 《Journal of virology》2013,87(13):7382-7392
The live attenuated simian immunodeficiency virus (SIV) SIVmac239Δnef is the most effective SIV/human immunodeficiency virus (HIV) vaccine in preclinical testing. An understanding of the mechanisms responsible for protection may provide important insights for the development of HIV vaccines. Leveraging the uniquely restricted genetic diversity of Mauritian cynomolgus macaques, we performed adoptive transfers between major histocompatibility complex (MHC)-matched animals to assess the role of cellular immunity in SIVmac239Δnef protection. We vaccinated and mock vaccinated donor macaques and then harvested between 1.25 × 109 and 3.0 × 109 mononuclear cells from multiple tissues for transfer into 12 naive recipients, followed by challenge with pathogenic SIVmac239. Fluorescently labeled donor cells were detectable for at least 7 days posttransfer and trafficked to multiple tissues, including lung, lymph nodes, and other mucosal tissues. There was no difference between recipient macaques'' peak or postpeak plasma viral loads. A very modest difference in viral loads during the chronic phase between vaccinated animal cell recipients and mock-vaccinated animal cell recipients did not reach significance (P = 0.12). Interestingly, the SIVmac239 challenge virus accumulated escape mutations more rapidly in animals that received cells from vaccinated donors. These results may suggest that adoptive transfers influenced the course of infection despite the lack of significant differences in the viral loads among animals that received cells from vaccinated and mock-vaccinated donor animals. 相似文献
179.
David M. Poitz Friedrich Stölzel Laleh Arabanian Jens Friedrichs Denitsa Docheva Matthias Schieker Fernando A. Fierro Uwe Platzbecker Rainer Ordemann Carsten Werner Martin Bornhäuser Ruth H. Strasser Gerhard Ehninger Thomas Illmer 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2013,1833(12):3396-3404
180.
Martin Pabst Richard M. Fischl Lothar Brecker Willy Morelle Alexander Fauland Harald Köfeler Friedrich Altmann Renaud Léonard 《The Plant journal : for cell and molecular biology》2013,76(1):61-72
A paradigm regarding rhamnogalacturonans II (RGII) is their strictly conserved structure within a given plant. We developed and employed a fast structural characterization method based on chromatography and mass spectrometry, allowing analysis of RGII side chains from microgram amounts of cell wall. We found that RGII structures are much more diverse than so far described. In chain A of wild‐type plants, up to 45% of the l –fucose is substituted by l –galactose, a state that is seemingly uncorrelated with RGII dimerization capacity. This led us to completely reinvestigate RGII structures of the Arabidopsis thaliana fucose‐deficient mutant mur1, which provided insights into RGII chain A biosynthesis, and suggested that chain A truncation, rather than l –fucose to l –galactose substitution, is responsible for the mur1 dwarf phenotype. Mass spectrometry data for chain A coupled with NMR analysis revealed a high degree of methyl esterification of its glucuronic acid, providing a plausible explanation for the puzzling RGII antibody recognition. The β–galacturonic acid of chain A exhibits up to two methyl etherifications in an organ‐specific manner. Combined with variation in the length of side chain B, this gives rise to a family of RGII structures instead of the unique structure described up to now. These findings pave the way for studies on the physiological roles of modulation of RGII composition. 相似文献