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991.
Lin JS Anaclet C Sergeeva OA Haas HL 《Cellular and molecular life sciences : CMLS》2011,68(15):2499-2512
Wakefulness and consciousness depend on perturbation of the cortical soliloquy. Ascending activation of the cerebral cortex
is characteristic for both waking and paradoxical (REM) sleep. These evolutionary conserved activating systems build a network
in the brainstem, midbrain, and diencephalon that contains the neurotransmitters and neuromodulators glutamate, histamine,
acetylcholine, the catecholamines, serotonin, and some neuropeptides orchestrating the different behavioral states. Inhibition
of these waking systems by GABAergic neurons allows sleep. Over the past decades, a prominent role became evident for the
histaminergic and the orexinergic neurons as a hypothalamic waking center. 相似文献
992.
993.
Vonk WI de Bie P Wichers CG van den Berghe PV van der Plaats R Berger R Wijmenga C Klomp LW van de Sluis B 《Cellular and molecular life sciences : CMLS》2012,69(1):149-163
Menkes disease (MD) is an X-linked recessive disorder characterized by copper deficiency resulting in a diminished function
of copper-dependent enzymes. Most MD patients die in early childhood, although mild forms of MD have also been described.
A diversity of mutations in the gene encoding of the Golgi-resident copper-transporting P1B-type ATPase ATP7A underlies MD. To elucidate the molecular consequences of the ATP7A mutations, various mutations in ATP7A associated with distinct phenotypes of MD (L873R, C1000R, N1304S, and A1362D) were analyzed in detail. All mutants studied
displayed changes in protein expression and intracellular localization parallel to a dramatic decline in their copper-transporting
capacity compared to ATP7A the wild-type. We restored these observed defects in ATP7A mutant proteins by culturing the cells
at 30°C, which improves the quality of protein folding, similar to that which as has recently has been demonstrated for misfolded
ATP7B, a copper transporter homologous to ATP7A. Further, the effect of the canine copper toxicosis protein COMMD1 on ATP7A
function was examined as COMMD1 has been shown to regulate the proteolysis of ATP7B proteins. Interestingly, in addition to
adjusted growth temperature, binding of COMMD1 partially restored the expression, subcellular localization, and copper-exporting
activities of the ATP7A mutants. However, no effect of pharmacological chaperones was observed. Together, the presented data
might provide a new direction for developing therapies to improve the residual exporting activity of unstable ATP7A mutant
proteins, and suggests a potential role for COMMD1 in this process. 相似文献
994.
995.
996.
Andréa Andrade Vilela 《Journal of Natural History》2018,52(7-8):415-428
Ants commonly participate simultaneously in mutualisms with honeydew-producing hemipterans and extrafloral nectar-bearing host plants. These interactions are based on the exchange of resources (honeydew and extrafloral nectar) for ant protection against natural enemies. The benefits may vary according to the species of ant interacting, and the outcomes for the host plant and hemipteran will depend on the results of the ant-plant-hemipteran relationship as a whole. We studied a plant-mealybug association with Camponotus crassus Mayr (Formicinae) and Ectatomma tuberculatum Olivier (Ectatomminae) in a Brazilian tropical savanna. We aimed to elucidate whether the frequency of visitation by different species of ants can be affected by neighbouring colonies of mealybugs, and whether these ant species influence the number of hemipterans in a different way. Furthermore, we intended to find out whether the interaction between ant and hemipteran has any effect on the proportion of fruit production or on the abundance of trophobiont and non-trophobiont herbivores, also influenced by the ant species. Our results show that neighbouring aggregations of mealybugs influenced the frequency of ant visitation and the ants affected the number of nymphs over time, with both positive results only for C. crassus. We also detected an indirect negative effect on proportion of fruit production and an increase in abundance of trophobiont and non-trophobiont herbivores in the presence of C. crassus-mealybug interaction. Thus, we provide further evidence that colonies of hemipterans interacting with ants can be beneficial for these herbivorous insects, but they are quite harmful to the host plant. Nevertheless, the outcomes can be highly conditional in relation to ant species. 相似文献
997.
Denilson Costa Martins Patrícia Maia Correia de Albuquerque Francinaldo Soares Silva José Manuel Macário Rebêlo 《Journal of Natural History》2018,52(11-12):627-644
There is a general lack of information concerning the diversity of bees belonging to the Euglossini tribe in Cerrado areas closest to the Brazilian Amazon. The state of Maranhão is situated in the northeast Brazilian Cerrado and has become the agricultural frontier of the country due to the advancement of monoculture and cattle farming. These activities have suppressed animal and plant populations in large areas of the Cerrado remnants, for which we have not yet obtained adequate scientific knowledge of local species. The objective of this study was to conduct a survey of Euglossini fauna in the northeast Cerrado. We evaluated the variation in species richness, composition and abundance between two distinct vegetation types: Cerrado sensu stricto (s.s.) and gallery forest. Male bees were captured from 7:00 a.m. to 5:00 p.m. over two consecutive days. Captures were carried out once per month from July 2012 to December 2013, using a combination of passive and active collection techniques, including baited traps, as well as a collector with an entomological net to collect bees near traps. We collected a total of 766 Euglossini males belonging to 24 species and five genera. The most abundant species were Eulaema bombiformis, Eulaema nigrita and Eulaema cingulata for the gallery forest site, whereas Eulaema nigrita, Euglossa melanotricha and Euglossa cordata were more abundant in the Cerrado s.s. The gallery forest yielded a higher number of male Euglossini (n = 503, 21 species) compared with the Cerrado s.s. (n = 263, 16 species). The presence of seven exclusive species in the gallery forest and three in the Cerrado s.s. indicated that both environments are important for the maintenance of Euglossini species in this region and highlight the increasing need for conservation programmes for the protection of Cerrado environments. 相似文献
998.
From axon–glial signalling to myelination: the integrating role of oligodendroglial Fyn kinase 总被引:1,自引:1,他引:0
Central nervous system myelination requires recognition and signalling processes between neuronal axons and oligodendrocytes.
Complex cellular rearrangements occur in myelination-competent oligodendrocytes requiring spatio-temporal control mechanisms.
Although the molecular repertoire is becoming increasingly transparent, the signalling mechanisms governing myelination initiation
are only poorly understood. The non-receptor tyrosine kinase Fyn has been implicated in axon–glial signal transduction and
in several cellular processes required for oligodendrocyte maturation and myelination. Here, we review oligodendroglial Fyn
signalling and discuss the role of Fyn in axon–glia interaction mediating myelination. 相似文献
999.
高浓度亚硫酸铵氧化反应过程研究 总被引:9,自引:0,他引:9
通过填料塔对亚硫酸铵氧化过程各影响因素进行了全面的研究。反应温度 30°C~ 75°C,氧气体积分数 φO2 =0 .2 1~ 1 ,亚硫酸根浓度 0 .3mol/L~ 5.0 mol/L,初始硫酸根浓度 0~ 1 .5mol/L,催化剂有铜、铁、钴、锌、锰的硫酸盐。实验结果表明 :在高浓度 ( [SO2 -3 ]>0 .5mol/L)下 ,亚硫酸铵的氧化速率随亚硫酸根浓度的增加而降低 ,硫酸根浓度的增加也使亚硫酸铵的氧化速率下降。因此 ,高浓度的亚硫酸铵不能被迅速完全地直接氧化成硫铵 ,要在较低浓度下氧化后再浓缩 ,该工艺过程的操作费用较高 相似文献
1000.