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71.
为全面了解毛竹中扩展蛋白的分子特征和表达模式,本研究利用生物信息学方法在毛竹基因组中共鉴定出43个扩展蛋白基因家族成员,属于4个亚家族(EXPA、EXPB、EXLA和EXLB),分别包含18、17、7和1个成员,分布在37个Scaffold上。除PeEXPA1没有内含子和PeEXLB1含有11个内含子外,其它毛竹扩展蛋白基因的内含子为1~5个。毛竹扩展蛋白基因编码蛋白长度为91~508个氨基酸,所有的氨基酸都具有高频密码子,大部分蛋白为碱性亲水性蛋白。大部分毛竹扩展蛋白二级结构中β转角占比例最少,而β折叠占比例最大,各亚家族多数成员具有类似的三级结构。qRT-PCR结果表明,18个EXPA亚家族成员在不同组织表达存在明显差异,除PeEXPA2、PeEXPA6外其它基因表达的最高值均出现在叶片中,表明它们可能在叶片生长过程中发挥着重要作用。 相似文献
72.
Patrick Gérardin Sylvain Sampériz Duksha Ramful Brahim Boumahni Marc Bintner Jean-Luc Alessandri Magali Carbonnier Isabelle Tiran-Rajaoefera Gilles Beullier Irénée Boya Tahir Noormahomed Jocelyn Oko? Olivier Rollot Liliane Cotte Marie-Christine Jaffar-Bandjee Alain Michault Fran?ois Favier Monique Kaminski Alain Fourmaintraux Xavier Fritel 《PLoS neglected tropical diseases》2014,8(7)
Background
Little is known about the neurocognitive outcome in children exposed to perinatal mother-to-child Chikungunya virus (p-CHIKV) infection.Methods
The CHIMERE ambispective cohort study compared the neurocognitive function of 33 p-CHIKV-infected children (all but one enrolled retrospectively) at around two years of age with 135 uninfected peers (all enrolled prospectively). Psychomotor development was assessed using the revised Brunet-Lezine scale, examiners blinded to infectious status. Development quotients (DQ) with subscores covering movement/posture, coordination, language, sociability skills were calculated. Predictors of global neurodevelopmental delay (GND, DQ≤85), were investigated using multivariate Poisson regression modeling. Neuroradiologic follow-up using magnetic resonance imaging (MRI) scans was proposed for most of the children with severe forms.Results
The mean DQ score was 86.3 (95%CI: 81.0–91.5) in infected children compared to 100.2 (95%CI: 98.0–102.5) in uninfected peers (P<0.001). Fifty-one percent (n = 17) of infected children had a GND compared to 15% (n = 21) of uninfected children (P<0.001). Specific neurocognitive delays in p-CHIKV-infected children were as follows: coordination and language (57%), sociability (36%), movement/posture (27%). After adjustment for maternal social situation, small for gestational age, and head circumference, p-CHIKV infection was found associated with GND (incidence rate ratio: 2.79, 95%CI: 1.45–5.34). Further adjustments on gestational age or breastfeeding did not change the independent effect of CHIKV infection on neurocognitive outcome. The mean DQ of p-CHIKV-infected children was lower in severe encephalopathic children than in non-severe children (77.6 versus 91.2, P<0.001). Of the 12 cases of CHIKV neonatal encephalopathy, five developed a microcephaly (head circumference <−2 standard deviations) and four matched the definition of cerebral palsy. MRI scans showed severe restrictions of white matter areas, predominant in the frontal lobes in these children.Conclusions
The neurocognitive outcome of children exposed to perinatal mother-to-child CHIKV infection is poor. Severe CHIKV neonatal encephalopathy is associated with an even poorer outcome. 相似文献73.
In recent years autophagy modulation has been shown to reduce or increase neuronal cell death in several models of neurodegeneration. How autophagy exerts these dual effects is currently unknown. Here we review recent evidence from our laboratory demonstrating that autophagy can protect the cell soma after axonal traumatic injury. Damage in the optic nerve induces retinal ganglion cell (RGC) death in glaucoma and other retinal diseases and is often modeled by axotomy of the optic nerve in laboratory animals. Using this well-known model of RGC degeneration we show that autophagy is strongly upregulated following the insult and before cell death. Enhancement of autophagy by pharmacological treatment with rapamycin decreases the number of degenerating neurons. Conversely, axotomy in Atg4B (-/-) mice increases the number of dying cells in the retinal ganglion cell layer. Similar findings were observed in Atg5 (flox/flox) mice following specific downregulation of the autophagy regulator ATG5 in RGCs, by intravitreal injection of a cre-expressing vector. Taken together, these findings point to a cytoprotective role of autophagy following axonal damage in vivo. 相似文献
74.
75.
J Boya 《Acta anatomica》1975,92(3):364-375
The author studied the ultrastructural characteristics of the microglial cell in the cerebral cortex of the adult rat and rabbit, admitting the identity and independence of this glial type in relation to the other cells of the nervous tissue. He also discussed the microglial nature of the pericytes ("pericytial microglia"). 相似文献
76.
Boya Wang Zhiwen Deng Yuting Xia Jiaxuan Hu Hongju Li Hao Wu Qiaobao Zhang Yun Zhang Huakun Liu Shixue Dou 《Liver Transplantation》2020,10(1)
Finding suitable electrode materials for alkali‐metal‐ion storage is vital to the next‐generation energy‐storage technologies. Polyantimonic acid (PAA, H2Sb2O6 · nH2O), having pentavalent antimony species and an interconnected tunnel‐like pyrochlore crystal framework, is a promising high‐capacity energy‐storage material. Fabricating electrochemically reversible PAA electrode materials for alkali‐metal‐ion storage is a challenge and has never been reported due to the extremely poor intrinsic electronic conductivity of PAA associated with the highest oxidation state Sb(V). Combining nanostructure engineering with a conductive‐network construction strategy, here is reported a facile one‐pot synthesis protocol for crafting uniform internal‐void‐containing PAA nano‐octahedra in a composite with nitrogen‐doped reduced graphene oxide nanosheets (PAA?N‐RGO), and for the first time, realizing the reversible storage of both Li+ and K+ ions in PAA?N‐RGO. Such an architecture, as validated by theoretical calculations and ex/in situ experiments, not only fully takes advantage of the large‐sized tunnel transport pathways (0.37 nm2) of PAA for fast solid‐phase ionic diffusion but also leads to exponentially increased electrical conductivity (3.3 S cm?1 in PAA?N‐RGO vs 4.8 × 10?10 S cm?1 in bare‐PAA) and yields an inside‐out buffer function for accommodating volume expansion. Compared to electrochemically irreversible bare‐PAA, PAA?N‐RGO manifests reversible conversion‐alloying of Sb(V) toward fast and durable Li+‐ and K+‐ion storage. 相似文献
77.
The immunohistochemical detection of bromodeoxyuridine (BrdU) was used to study the time of origin of the cells in the pineal gland of the rat. A study was made involving 17 groups of 4 rats each, administered with a single dose of bromodeoxyuridine (BrdU, 25 mg/kg) in 7 phases of the embryonic period (E15 to E21) and in 10 postnatal phases (between P0 and P30), followed by determination in each rat of the number of visible immune-labeled cells in the pineal gland 60 days after birth. The results show that approximately 60% of the pineal cells underwent the last division(s) prior to differentiation in the prenatal period between E18 and E21. The rest of the pineal cells originated after birth, particularly in the first 5 postnatal days. 相似文献
78.
Ischemia results in increased phosphorylation of NMDA receptors. To investigate the possible role of lipid rafts in this increase, lipid rafts and post-synaptic densities (PSDs) were isolated by the extraction of rat brain synaptosomes with Triton X-100 followed by sucrose density gradient centrifugation. Lipid rafts accounted for the majority of PSD-95, whereas SAP102 was predominantly located in PSDs. Between 50 and 60% of NMDA receptors were associated with lipid rafts. Greater than 85-90% of Src and Fyn were present in lipid rafts, whereas Pyk2 was mainly associated with PSDs. Lipid rafts and PSDs were isolated from animals subjected to 15 min of global ischemia followed by 6 h of recovery. Ischemia did not affect the yield, density, flotillin-1 or cholesterol content of lipid rafts. Following ischemia, the phosphorylation of NR1 by protein kinase C and tyrosine phosphorylation of NR2A and NR2B was increased in both lipid rafts and PSDs, with a greater increase in tyrosine phosphorylation occurring in the raft fraction. Following ischemia, NR1, NR2A and NR2B levels were elevated in PSDs and reduced in lipid rafts. The findings are consistent with a model involving close interaction between lipid rafts and PSDs and a role for lipid rafts in ischemia-induced signaling pathways. 相似文献
79.
Sex allocation theory predicts that: (1) resources allocated to androecium should decrease with an increase in selfing, (2) a decrease in androecium biomass should be accompanied by an increase in the biomass of pistils, and (3) a decrease in androecium biomass should be coupled with a decrease in flower size, specifically corolla biomass. Another predicted change in reproductive traits associated with variation in selfing concerns seed to ovule ratios, but does not directly stem from sex allocation theory. It has been postulated that seed to ovule ratios should be positively correlated with the amount of selfing. These predictions were tested for six accessions of pigeonpea,Cajanus cajan L., that differed in selfing rates. The results were remarkably in accordance with the predictions. We conclude that sex allocation theory provides a powerful tool to understand the evolution of many reproductive traits in plants. 相似文献
80.