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41.
In Lake Maggiore, the density of the invertebrate predator Bythotrepheslongimanus increased following lake re-oligotrophication inthe late 1980s. This "invasion" was followed by dramatic changesin the pelagic food web, consistent with those that followedthe establishment of B. longimanus in North American lakes whereit is not native. In this contribution, we explore the modernsuccess of B. longimanus in Lake Maggiore by investigating itsphenology and population density, and their correlations withabiotic and biotic factors during the period from 1981 to 2003.A 10-fold increase in the abundance of B. longimanus followedan earlier start and longer duration of annual population growth.Increased prey resources and decreased predation pressure werenot observed during the B. longimanus density increase. Instead,a rise in lake temperature may have altered the reproductivecycle of this species. Furthermore, the depth and duration ofa refuge from visually orienting fish predators increased duringthese 20 years, as a result of changes in the thermal stratificationregime of the lake. This case study provides a timely exampleof how climatic changes may interact with biotic drivers (e.g.fish predation) to influence the density and phenology of aninvertebrate predator. 相似文献
42.
Protein and peptide arrays: recent trends and new directions 总被引:3,自引:0,他引:3
Microarrays of proteins and peptides make it possible the screening of thousands of binding events in a parallel and high throughput fashion; therefore they are emerging as a powerful tool for proteomics and clinical assays. The complex nature of Proteome, the wide dynamic range of protein concentration in real samples and the critical role of immobilized protein orientation must be taken into account to maximize the utility of protein microarrays. Immobilization strategy and designing of an ideal local chemical environment on the solid surface are both essential for the success of a protein microarray experiment. This review article will focus on protein and peptide arrays highlighting their technical challenges and presenting new directions by means of a set of selected recent applications. 相似文献
43.
Burbaeva GSh Boksha IS Tereshkina EB Savushkina OK Starodubtseva LI Turishcheva MS Mukaetova-Ladinska E 《Neurochemical research》2007,32(9):1434-1444
We have used a systemic approach to establish a relationship between enzyme measures of glial glutamate and energy metabolism
(glutamine synthetase and glutamine synthetase-like protein, glutamate dehydrogenase isoenzymes, brain isoform creatine phosphokinase)
and two major glial proteins (glial fibrillary acidic protein and myelin basic protein) in autopsied brain samples taken from
patients with schizophrenia (SCH) and mentally healthy subjects (23 and 22 cases, respectively). These biochemical parameters
were measured in tissue extracts in three brain areas (prefrontal cortex, caudate nucleus, and cerebellum). Significant differences
in the level of at least one of the glutamate metabolizing enzymes were observed between two studied groups in all studied
brain areas. Different patterns of correlative links between the biochemical parameters were found in healthy and schizophrenic
brains. These findings give a new perspective to our understanding of the impaired regulation of enzyme levels in the brain
in SCH. 相似文献
44.
Pozzolini M Sturla L Cerrano C Bavestrello G Camardella L Parodi AM Raheli F Benatti U Müller WE Giovine M 《Marine biotechnology (New York, N.Y.)》2004,6(6):594-603
In some sponges peculiar proteins called silicateins catalyze silica polymerization in ordered structures, and their study is of high interest for possible biotechnological applications in the nanostructure industry. In this work we describe the isolation and the molecular characterization of silicatein from spicules of Petrosia ficiformis, a common Mediterranean sponge, and the development of a cellular model (primmorphs) suitable for in vitro studies of silicatein gene regulation. The spicule of P. ficiformis contains an axial filament composed of 2 insoluble proteins, of 30 and 23 kDa. The 23-kDa protein was characterized, and the full-length cDNA was cloned. The putative amino acid sequence has high homology with previously described silicateins from other sponge species and also is very similar to cathepsins, a cystein protease family. Finally, P. ficiformis primmorphs express the silicatein gene, suggesting that they should be a good model for biosilicification studies. 相似文献
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Marina Lozano Almudena Estalrrich Luca Bondioli Ivana Fiore José‐Maria Bermúdez de Castro Juan Luis Arsuaga Eudald Carbonell Antonio Rosas David W. Frayer 《Evolutionary anthropology》2017,26(6):313-324
Fossil hominids often processed material held between their upper and lower teeth. Pulling with one hand and cutting with the other, they occasionally left impact cut marks on the lip (labial) surface of their incisors and canines. From these actions, it possible to determine the dominant hand used. The frequency of these oblique striations in an array of fossil hominins documents the typically modern pattern of 9 right‐ to 1 left‐hander. This ratio among living Homo sapiens differs from that among chimpanzees and bonobos and more distant primate relatives. Together, all studies of living people affirm that dominant right‐handedness is a uniquely modern human trait. The same pattern extends deep into our past. Thus far, the majority of inferred right‐handed fossils come from Europe, but a single maxilla from a Homo habilis, OH‐65, shows a predominance of right oblique scratches, thus extending right‐handedness into the early Pleistocene of Africa. Other studies show right‐handedness in more recent African, Chinese, and Levantine fossils, but the sample compiled for non‐European fossil specimens remains small. Fossil specimens from Sima del los Huesos and a variety of European Neandertal sites are predominately right‐handed. We argue the 9:1 handedness ratio in Neandertals and the earlier inhabitants of Europe constitutes evidence for a modern pattern of handedness well before the appearance of modern Homo sapiens. 相似文献
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Summary Three patients with mental retardation and multiple congenital abnormalities are described.Although their clinical appearance was not suggestive of Down's syndrome, chromosome studies showed a non-disjunctional trisomy 21 in two of the patients. The third case had an unsuspected XXY karyotype. 相似文献
50.
Yann Cormerais Marina Pagnuzzi‐Boncompagni Sandra Schrtter Sandy Giuliano Eric Tambutt Hitoshi Endou Michael F. Wempe Gilles Pags Jacques Pouyssgur Vincent Picco 《Journal of cellular and molecular medicine》2019,23(4):2711-2718
Most cases of medulloblastoma (MB) occur in young children. While the overall survival rate can be relatively high, current treatments combining surgery, chemo‐ and radiotherapy are very destructive for patient development and quality of life. Moreover, aggressive forms and recurrences of MB cannot be controlled by classical therapies. Therefore, new therapeutic approaches yielding good efficacy and low toxicity for healthy tissues are required to improve patient outcome. Cancer cells sustain their proliferation by optimizing their nutrient uptake capacities. The L‐type amino acid transporter 1 (LAT1) is an essential amino acid carrier overexpressed in aggressive human cancers that was described as a potential therapeutic target. In this study, we investigated the therapeutic potential of JPH203, a LAT1‐specific pharmacological inhibitor, on two independent MB cell lines belonging to subgroups 3 (HD‐MB03) and Shh (DAOY). We show that while displaying low toxicity towards normal cerebral cells, JPH203 disrupts AA homeostasis, mTORC1 activity, proliferation and survival in MB cells. Moreover, we demonstrate that a long‐term treatment with JPH203 does not lead to resistance in MB cells. Therefore, this study suggests that targeting LAT1 with JPH203 is a promising therapeutic approach for MB treatment. 相似文献