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881.
882.
B Falkiewicz W Wisniowski A S Kolodziejczyk K Wisniewski L Lankiewicz 《Nucleic acids symposium series》1999,(42):29-30
PNAs are DNA analogues in which the nucleic acid's backbone is replaced by a chiral or achiral pseudopeptide backbone and nucleobases are attached to the backbone by methylene carbonyl linkers. The easy to modify PNA structure gives the possibility to obtain monomers, and subsequently oligomers, with improved properties. We have synthesised several new PNA monomers, starting from a series of 2'-substituted methyl N-(2-Boc-aminoethyl)glycinates. The pseudodipeptides were obtained using modified Kosynkina's method, based on the reductive amination of N-Boc-protected alpha-amino aldehydes [glycinal, isoleucinal, valinal, tryptophanal, serinal(Bzl), prolinal] with methyl glycinate. The compounds were then acylated with nucleic acid base derivatives by simplified procedure, and the purification was limited to the last step of the synthesis. The applied procedure is useful in synthesis of various chiral PNA monomers. 相似文献
883.
884.
Anne E. Thessen Paul Bogdan David J. Patterson Theresa M. Casey Csar Hinojo-Hinojo Orlando de Lange Melissa A. Haendel 《PLoS biology》2021,19(3)
Decades of reductionist approaches in biology have achieved spectacular progress, but the proliferation of subdisciplines, each with its own technical and social practices regarding data, impedes the growth of the multidisciplinary and interdisciplinary approaches now needed to address pressing societal challenges. Data integration is key to a reintegrated biology able to address global issues such as climate change, biodiversity loss, and sustainable ecosystem management. We identify major challenges to data integration and present a vision for a “Data as a Service”-oriented architecture to promote reuse of data for discovery. The proposed architecture includes standards development, new tools and services, and strategies for career-development and sustainability.Data integration is key to the reintegration of biology and the pursuit of global issues such as climate change, biodiversity loss, and sustainable ecosystem management. This Essay defines the primary challenges in data integration and presents a vision for a "Data as a Service" (DaaS) oriented architecture that enables frictionless data reuse, hypothesis testing, and discovery. 相似文献
885.
886.
Maria Żaak Paweł Migula Dominika Stygar Bogdan Doleżych Katarzyna Michalczyk 《Comptes rendus biologies》2012,335(10-11):645-656
Cameraria ohridella is an invasive leaf miner, a severe pest of horse chestnut trees. Chemical control needs recognition of intrinsic metabolic capability to cope with external stressing factors. Our tasks were to check annual effects of generation, and host tree age on detoxifying abilities of the last larval stage. Activities of CAT, SOD, GSTPX, GST CarE and AChE were assayed in the midgut of larvae from two localities during 3 years and three generations, annually. Activities of GSTPX and GST were high, but CAT and SOD were low in relation to other lepidopteran larvae. In general, the second generation larvae had the highest activity, indicating an effective defence against allelochemicals produced by the host. Effects of host tree age were significant for SOD, GSTPX and CarE activities. Significant annual differences on enzyme profiles of CAT, SOD, CarE and AChE reflected differences of temperature and precipitation between consecutive years. 相似文献
887.
Gy?rgy Fejer Lisa Drechsel Jan Liese Ulrike Schleicher Zsolt Ruzsics Nicola Imelli Urs F. Greber Simone Keck Bernd Hildenbrand Anne Krug Christian Bogdan Marina A. Freudenberg 《PLoS pathogens》2008,4(11)
The early systemic production of interferon (IFN)-αβ is an essential component of the antiviral host defense mechanisms, but is also thought to contribute to the toxic side effects accompanying gene therapy with adenoviral vectors. Here we investigated the IFN-αβ response to human adenoviruses (Ads) in mice. By comparing the responses of normal, myeloid (m)DC- and plasmacytoid (p)DC-depleted mice and by measuring IFN-αβ mRNA expression in different organs and cells types, we show that in vivo, Ads elicit strong and rapid IFN-αβ production, almost exclusively in splenic mDCs. Using knockout mice, various strains of Ads (wild type, mutant and UV-inactivated) and MAP kinase inhibitors, we demonstrate that the Ad-induced IFN-αβ response does not require Toll-like receptors (TLR), known cytosolic sensors of RNA (RIG-I/MDA-5) and DNA (DAI) recognition and interferon regulatory factor (IRF)-3, but is dependent on viral endosomal escape, signaling via the MAP kinase SAPK/JNK and IRF-7. Furthermore, we show that Ads induce IFN-αβ and IL-6 in vivo by distinct pathways and confirm that IFN-αβ positively regulates the IL-6 response. Finally, by measuring TNF-α responses to LPS in Ad-infected wild type and IFN-αβR−/− mice, we show that IFN-αβ is the key mediator of Ad-induced hypersensitivity to LPS. These findings indicate that, like endosomal TLR signaling in pDCs, TLR-independent virus recognition in splenic mDCs can also produce a robust early IFN-αβ response, which is responsible for the bulk of IFN-αβ production induced by adenovirus in vivo. The signaling requirements are different from known TLR-dependent or cytosolic IFN-αβ induction mechanisms and suggest a novel cytosolic viral induction pathway. The hypersensitivity to components of the microbial flora and invading pathogens may in part explain the toxic side effects of adenoviral gene therapy and contribute to the pathogenesis of adenoviral disease. 相似文献
888.
The environmental changes induced by projects occurring in an area are evaluated by cumulative impact assessments (CIA), which
consider the consequences of multiple projects, each insignificant on its own, yet important when evaluated collectively.
When future human activities are of interest, the proposed activities are included in CIA using an analytical platform that
can supply precise predictions but with asymptotically null accuracy. To compensate for the lack of accuracy we propose a
shift in the paradigm governing CIA. The paradigm shift advocates a change in the focus of CIA investigations from the detailed
analysis of one unlikely future to the identification of patterns describing the future changes in the environment. To illustrate
the paradigm shift, a set of 144 possible and equally likely futures were developed and used to identify the potential impacts
of forest harvesting and petroleum drilling on the habitat of moose and marten. The univariate and multivariate analysis of
two measures of habitat, namely average habitat suitability index (HSI) and surface of the stands with HSI >0.5, revealed
at least three distinct periods in the next 100 years. Multivariate analysis also showed that habitat quality is of immediate
importance and marten is sensitive during the first third of the century. Our findings indicate that the spatial and temporal
arrangement of the human disturbances could be more important than the magnitude of the disturbance. The attributes associated
with significant environmental changes are harvesting age and the investigated environmental elements of an ecosystem, in
this case the species habitat. 相似文献
889.
Peroxidase activity of red raspberry canes was dependent on the cultivar and influenced the subsequent lignification. After
inoculation with Didymella applanata, responsible for the spur blight cane disease, the activity of soluble cytoplasmic enzyme increased in the moderately resistant
‘Latham’ and susceptible ‘Malling Promise’, similarly for syringaldazine and guaiacol as hydrogen donors. Systemic induction
found in ‘Latham’ was recognized as a symptom of defence mechanism responsible for fungal restriction. Locally enhanced peroxidase
activity in the ‘M.Promise’ tissues was related to the local lignification and/or may be associated with the loss of cell
integrity caused by pathogen penetration. Pathogen-induced changes of cell wall peroxidases were similar in both cultivars
mentioned above. No influence of the infection was found in the high susceptible Zeva cultivar.
Using native-PAGE analysis and horizontal starch electrophoresis of soluble fraction five constitutive acidic isoperoxidases
were detected in ‘Latham’ and three in ‘M. Promise’. The infection process was accompanied by the appearance of two new anodic
isoforms. 相似文献
890.