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241.
Background
Cross-modal plasticity is characterized as the hypersensitivity of remaining modalities after a sensory function is lost in rodents, which ensures their awareness to environmental changes. Cellular and molecular mechanisms underlying cross-modal sensory plasticity remain unclear. We aim to study the role of different types of neurons in cross-modal plasticity.Methodology/Principal Findings
In addition to behavioral tasks in mice, whole-cell recordings at the excitatory and inhibitory neurons, and their two-photon imaging, were conducted in piriform cortex. We produced a mouse model of cross-modal sensory plasticity that olfactory function was upregulated by trimming whiskers to deprive their sensory inputs. In the meantime of olfactory hypersensitivity, pyramidal neurons and excitatory synapses were functionally upregulated, as well as GABAergic cells and inhibitory synapses were downregulated in piriform cortex from the mice of cross-modal sensory plasticity, compared with controls. A crosswire connection between barrel cortex and piriform cortex was established in cross-modal plasticity.Conclusion/Significance
An upregulation of pyramidal neurons and a downregulation of GABAergic neurons strengthen the activities of neuronal networks in piriform cortex, which may be responsible for olfactory hypersensitivity after a loss of whisker tactile input. This finding provides the clues for developing therapeutic strategies to promote sensory recovery and substitution. 相似文献242.
Although attention-deficit/hyperactivity disorder (ADHD) has been recognized as a disorder affecting individuals across the life cycle since the end of the nineties, there is still considerable debate on how to conceptualize the disorder in adults, and on the best way to operationalize diagnostic criteria for this age range. In this comprehensive non-systematic review of the literature, we provide data about prevalence and presentation of ADHD in adulthood as well as discuss major problems in applying criteria developed for children in assessing adults (clinical utility, threshold of symptoms for diagnosis, full ADHD diagnosis in childhood, information source, and additional dimensions for diagnosis-executive functioning impairment and emotional impulsivity). In addition, we provide some recommendations for improving ADHD diagnostic criteria in adulthood. 相似文献
243.
Dihydrodipicolinate synthase is a key enzyme in the lysine biosynthesis pathway that catalyzes the condensation of pyruvate and aspartate semi-aldehyde. A series of phenolic ketoacid derivatives that mimic the proposed enzymatic intermediate were designed as potential inhibitors of this enzyme and were synthesized from simple precursors. The ketoacid derivatives were shown to act as slow and slow-tight binding inhibitors. Mass spectrometric experiments provided further evidence to support the proposed model of inhibition, demonstrating either an encounter complex or a condensation product for the slow and slow-tight binding inhibitors, respectively. 相似文献
244.
Amphoterin-induced gene and ORF (AMIGO) is a brain-enriched transmembrane immunoglobulin (Ig) superfamily protein with six extracellular leucine-rich repeats (LRR) and a single immunoglobulin-like (Ig) domain. We report here that AMIGO is a glycosylated protein widely expressed in the central nervous system (CNS), and can be found in neurons, astrocytes as well as oligodendrocytes. In morphologically mature primary neurons, endogenous AMIGO, and transfected full length AMIGO (AMIGO-FL) are largely dendritic, while AMIGO with its LRR domain deleted (AMIGO-Ig) is predominantly axonal. In line with AMIGO's dendritic localization, siRNA-mediated silencing of AMIGO resulted in reduced dendritic growth of cortical neurons in culture. SH-SY5Y cells stably over-expressing AMIGO are more resistant to apoptosis induced by staurosporine and H(2) O(2) compared to vector controls. AMIGO therefore likely plays important roles in dendritic outgrowth during development, and could modulate the survival of developing and adult neurons. 相似文献
245.
Since the beginning of the new millennium, many conservation biologists and forest managers have been discussing the future of European forests. Historical evidence shows that the diversity of saproxylic beetles, a key measure of forest biodiversity, has declined at a frightening pace. Most of the data regarding species-rich forests were collected during a period when most European forests were managed using traditional management practices. We present extinction and genesis of relictual distribution of Cucujus haematodes, one of the three most endangered saproxylic beetles in the EU. We also analyse and compare threats to its presence and extinction according to forest history, management and current conditions in European forests. Our review showed that one of the main aims of conservation efforts relating to saproxylic beetles should focus on the refinement of the profound effects of commercial forestry and on respect for forest history and traditional forest management. Traditional management practices and their principles present one solution to the problem of decreasing forest biodiversity. We believe that our review can help stop the decrease of forest biodiversity in an era when people and large institutions are increasingly concerned about nature and the environment. 相似文献
246.
对水稻和拟南芥等模式植物的研究表明,NPR1(nonexpressor of pathogenesis-related genes 1)是依赖于SA通路的防御反应调节基因,但在辣椒和烟草等茄科作物中该蛋白的功能还鲜有报道。研究从辣椒cDNA文库中分离获得一个NPR1的类似物全长cDNA(CaNPR1),并获得了其超表达的转基因烟草T1代株系。研究结果表明,这些株系与其野生型植株没有明显表型差异,但却表现出较野生型植株更高的抗青枯菌侵染活性。同时,研究还发现CaNPR1的超表达还显著提高了防御相关基因的表达,表明NPR1在不同植物间具有较强的功能保守性。 相似文献
247.
Cucujus tulliaesp. n. is described as a new member of genus Cucujus Fabricius, 1775 (Coleoptera, Cucujidae), which enumerates at present eleven species distributed in Eurasia and northern America. This saproxylic beetle is the first Cucujus species known only from Mediterranean and it is probably endemic to Calabria (Italy). The species was found especially in old-growth mountain forests of high conservation value (i.e. national parks) dominated by Calabrian pine (Pinus laricio calabrica). We hypothesize that Cucujus tulliae sp. n. probably evolved from isolated populations of Cucujus haematodes Erichson, 1845. The species is thus relictual and of high conservation value, corresponding at least to endangered (EN) category with respect to recent IUCN criterion. Cucujus tulliae sp. n. is here compared with two species native to Europe - Cucujus haematodes and Cucujus cinnaberinus (Scopoli, 1763) and with the Caucasian Cucujus haematodes caucasicus Motschulsky, 1845, which is confirmed as a valid subspecies. The male genitalia of this Caucasian form have been examined and illustrated for the first time. A comprehensive key to adults and larvae of European species is provided. 相似文献
248.
Iva Smykalová Ji?í Horá?ek Michaela Kubo?iová Prokop ?mirous Jr Ale? Soukup Nikol Gasmanová Miroslav Griga 《In vitro cellular & developmental biology. Plant》2012,48(1):30-39
Plant regeneration was obtained from cultured anthers and hypocotyl segments of caraway (Carum carvi L.). Microspore- and somatic tissue-derived embryos were compared by observation of the regeneration process under identical
induction conditions. Fluorescent microscopy with DAPI staining showed initiation of cell divisions and formation of embryogenic
callus and somatic embryos from anther sacs, with production of embryos of both microspore and somatic origin. Induction of
somatic embryos from hypocotyl-derived callus was also demonstrated. Isozyme native polyacrylamide gel electrophoresis was
used to identify haploids and doubled haploids, and to determine the frequency of spontaneous diploidization of regenerated
plants of microspore origin. Donor plants (2n = 20) and their anther-derived derivative plants (n = 10, 2n = 20, 4n = 40) in callus stage or leafy rosette stage were compared. The esterase (EST) band patterns of regenerated plants differed
from the heterozygous parental material, suggesting that the regenerated plants were microspore-derived haploid/doubled haploid
plants. The similar profile of EST bands between the diploid anther-derived plants and a sample of the donor plants corresponded
to a somatic regeneration pathway. Although the selected induction conditions revealed no preference for induction of microspore
embryogenesis, the anther culture protocol established for caraway utilizing isozyme segregating EST loci markers is suitable
for DH production. 相似文献
249.
Interaction of cis-dichlorodiammineplatinum (II) with DNA 总被引:5,自引:0,他引:5
250.