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11.
Sven Rossel Patricia Kaiser Maya Bode-Dalby Jasmin Renz Silke Laakmann Holger Auel Wilhelm Hagen Pedro Martínez Arbizu Janna Peters 《Molecular ecology resources》2023,23(2):382-395
Species identification is pivotal in biodiversity assessments and proteomic fingerprinting by MALDI-TOF mass spectrometry has already been shown to reliably identify calanoid copepods to species level. However, MALDI-TOF data may contain more information beyond mere species identification. In this study, we investigated different ontogenetic stages (copepodids C1–C6 females) of three co-occurring Calanus species from the Arctic Fram Strait, which cannot be identified to species level based on morphological characters alone. Differentiation of the three species based on mass spectrometry data was without any error. In addition, a clear stage-specific signal was detected in all species, supported by clustering approaches as well as machine learning using Random Forest. More complex mass spectra in later ontogenetic stages as well as relative intensities of certain mass peaks were found as the main drivers of stage distinction in these species. Through a dilution series, we were able to show that this did not result from the higher amount of biomass that was used in tissue processing of the larger stages. Finally, the data were tested in a simulation for application in a real biodiversity assessment by using Random Forest for stage classification of specimens absent from the training data. This resulted in a successful stage-identification rate of almost 90%, making proteomic fingerprinting a promising tool to investigate polewards shifts of Atlantic Calanus species and, in general, to assess stage compositions in biodiversity assessments of Calanoida, which can be notoriously difficult using conventional identification methods. 相似文献
12.
Ferdinand Bohlmann Pahup Singh Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(2):371-374
An investigation of the aerial parts of Chromolaena chasleae afforded a prostaglandin-like acid, whose structure followed from the 1H NMR spectral data and from the reaction with periodate, which afforded a hemiacetal. From a new Chromolaena species, three novel cadinene derivatives were isolated, which were closely related to those isolated previously from this genus. 相似文献
13.
Ferdinand Bohlmann Wolfgang Kramp Jasmin Jakupovic Harold Robinson Robert M. King 《Phytochemistry》1982,21(2):399-403
The aerial parts of Baccharis minutiflora afforded in addition to known compounds eight new ent-kaurane derivatives, one being a homo kaurane, while the aerial parts of B. alatemoides gave two pairs of epimeric clerodane derivatives, which, however, had to be modified chemically before they could be separated. The stereochemistry of these diterpenes could not be elucidated with certainty. 相似文献
14.
Ferdinand Bohlmann Maniruddin Ahmed Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(3):691-694
An investigation of Brickellia diffusa afforded three new dehydronerolidol derivatives and five new labdane derivatives, all highly oxygenated. The structures were elucidated by spectroscopic methods and a few chemical transformations. The compounds isolated showed close relationships to those isolated from Brickellia sp. 相似文献
15.
Ferdinand Bohlmann Alfons Adler Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(6):1349-1355
The investigation of two Mikania species, both previously placed in the genus Kanimia, afforded in addition to known compounds several new germ 相似文献
16.
Ferdinand Bohlmann Naleen Borthakur Jasmin Jakupovic Joachim Pickard 《Phytochemistry》1982,21(6):1357-1360
An investigation of Ursinia saxatilis afforded in addition to known compounds a new eudesmanolide derived from ursialpinolide, a germacranolide rel 相似文献
17.
Ferdinand Bohlmann Nezhun Ates Jasmin Jakupovic Robert M. King Harold Robinson 《Phytochemistry》1982,21(11):2691-2697
Artemisia douglasiana afforded, in addition to known compounds, two new C14-acetylenes, five longipinene derivatives, three nerolidol derivatives, a lactone and a ketone with a new carbon skeleton and lavendulol-2-methylbutyrate. The structures were elucidated by spectroscopic methods and some chemical transformations. The configurations of several oxo longipinene-7, 9-di- and 7, 8, 9-triesters isolated previously were corrected. The biogenesis of the new lactones is discussed briefly. 相似文献
18.
Fischer rat protective antiserum (F-2x) prepared from Schistosoma mansoni-infected rats was used to screen an adult worm cDNA library constructed in a lambda gt11 bacteriophage expression vector. This led to the isolation of several clones yielding proteins reactive with antibodies in the infection serum. Counter-screening of these clones with Wistar-Furth rat nonprotective antiserum (W-2x) enabled identification of clones either uniquely or preferentially reacting with F-2x, in addition to clones of nearly equal reactivity with both antisera. Six clones were further characterized. Five expressed beta-galactosidase/S. mansoni fusion proteins which migrated more slowly in sodium dodecyl sulfate-polyacrylamide gel electrophoresis than beta-galactosidase and all were reactive in a Western immunoblot assay. The cDNA insert sizes in the clones ranged from 150 to 900 base pairs. Rabbit antibodies prepared against fusion proteins from three of the clones recognized biosynthetically radio-labeled 4-week worm proteins of sizes 20, 38, and 70 kDa, respectively. The 20- and 38-kDa proteins were among the protein antigens uniquely recognized by the F-2x protective antiserum. These proteins are therefore candidates for protective vaccine antigens and the recombinant lambda clones are now serving as useful reagents for obtaining the corresponding nucleotide gene sequences. 相似文献
19.
F. Smadja-Joffe M. C. Le Bousse-Kerdiles B. Klein E. P. Malaise C. Jasmin V. Degiorgis 《Cell proliferation》1982,15(2):169-178
Abstract. Cell proliferation kinetics of the sarcoma induced by Moloney virus was studied in newborn Swiss OFl mice.
After in vivo injection of tritiated thymidine, followed by autoradiography, it was shown that the majority of cells were actively proliferating (labelling index; 31%, growth fraction 78%). The mean cell cycle was 16 hr and cell loss was relatively low (cell loss factor 48%). The study of tumour specific activity with time after a single [ in vivo ] injection of [3 H]dR or [125 I]UdR did not demonstrate the same degree of cell loss as that calculated by autoradiography. This result is consistent with a massive reutilization of radioactivity released by normal tissues. 相似文献
After in vivo injection of tritiated thymidine, followed by autoradiography, it was shown that the majority of cells were actively proliferating (labelling index; 31%, growth fraction 78%). The mean cell cycle was 16 hr and cell loss was relatively low (cell loss factor 48%). The study of tumour specific activity with time after a single [ in vivo ] injection of [
20.
Inheritance of susceptibility to the myeloproliferative sarcoma virus: effect of the Fv-2 locus and evidence for a myeloproliferative sarcoma virus resistance locus. 总被引:5,自引:2,他引:3
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Myeloproliferative sarcoma virus (MPSV) causes a generalized stem cell leukemia with erythroid and myeloid hyperplasia in adult mice. MPSV also transforms fibroblasts. Mice congenic for the Fv-2 locus showed marked differences in susceptibility to MPSV according to the Fv-2 genotype. MPSV was injected into C57BL/6 Fvs and C57BL/6 Fv-2r mice congenic except for the Fv-2 locus. C57BL/6 mice with the Fvs genotype were much more susceptible to MPSV than were those with the Fvr genotype. Both DDD Fv-2r mice congenic with DDD Fv-2s mice except for the Fv-2 locus and DDD Fv-2s mice, however, were sensitive to spleen focus formation by MPSV. These data indicate that at least one additional resistance locus to MPSV is present in C57BL/6 mice but not in DDD mice. Both the Fv-2 locus and the putative MSPV resistance locus (loci) Mpsvr appear to be epistatic to either of the sensitivity loci. Fibroblast focus formation by MPSV was obtained well in C57BL/6 Fv-2r and C57BL/6 Fvs fibroblasts, indicating that the genes for MPSV resistance (Fv-2r and Mpsvr) were not operating in fibroblast cells. A model is proposed which may account for the differences in response of genetically different mice to MPSV and Friend spleen focus-forming virus. 相似文献