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11.
Xiaojing Meng Lingxiao Yue An Liu Wenjuan Tao Li Shi Wan Zhao Zhongmin Wu Zhi Zhang Liecheng Wang Xulai Zhang Wenjie Zhou 《The Journal of biological chemistry》2022,298(8)
Pain is a multidimensional perception that includes unpleasant somatosensory and affective experiences; however, the underlying neural circuits that mediate different components of pain remain elusive. Although hyperactivity of basolateral amygdala glutamatergic (BLAGlu) neurons is required for the somatosensory and emotional processing of pain, the precise excitatory inputs to BLAGlu neurons and their roles in mediating different aspects of pain are unclear. Here, we identified two discrete glutamatergic neuronal circuits in male mice: a projection from the insular cortex glutamatergic (ICGlu) to BLAGlu neurons, which modulates both the somatosensory and affective components of pain, and a projection from the mediodorsal thalamic nucleus (MDGlu) to BLAGlu neurons, which modulates only the aversive-affective component of pain. Using whole-cell recording and fiber photometry, we found that neurons within the IC→BLA and MD→BLA pathways were activated in mice upon inflammatory pain induced by injection of complete Freund’s adjuvant (CFA) into their paws. Optical inhibition of the ICGlu→BLA pathway increased the nociceptive threshold and induced behavioral place preference in CFA mice. In contrast, optical inhibition of the MDGlu→BLA pathway did not affect the nociceptive threshold but still induced place preference in CFA mice. In normal mice, optical activation of the ICGlu→BLA pathway decreased the nociceptive threshold and induced place aversion, while optical activation of the MDGlu→BLA pathway only evoked aversion. Taken together, our results demonstrate that discrete ICGlu→BLA and MDGlu→BLA pathways are involved in modulating different components of pain, provide insights into its circuit basis, and better our understanding of pain perception. 相似文献
12.
砷是一种致癌物,是心血管、外周血管疾病、神经疾病、糖尿病和各种癌症的致病因素。目的:利用GO数据库和KEGG数据库等生物信息学方法对GEO数据库数据中的差异表达基因进行评价。利用生物信息学分析软件对差异基因进行功能富集、功能注释分析和生存分析。利用Cytoscape上的蛋白-蛋白相互作用网络(Protein-protein interaction network, PPI)软件对179个差异基因进行筛选和分析。结果发现126个基因作用于蛋白靶点,其中有10个基因为关键基因分别为:PSMB3、HSP701、HSPE1、STIP1、HSPD1、HSP70、DNAJB1B、HSP90AA1.1、HSPA9H和TCP1。核心基因主要作用于内质网中的蛋白质加工通路。这可能会为砷对肝脏损伤的潜在生物标志物和生物学机制提供新的思路。 相似文献
13.
It was well known that beta-amyloid (Abeta) and tau protein play an important role in pathological procedure of Alzheimer's disease (AD), a senile dementia. The growth inhibitory factor (GIF, also named metallothionein-3, MT-3) had been demonstrated to inhibit the outgrowth of cortex neurons in the medium with extract of the AD patient brain. In our experiments, it was found that the neurons of cortex and the PC12 (pheochromocytoma) cells could be protected from the cytotoxicity of beta-amyloid 25-35 in presence of GIF and its domains. Additionally, GIF can scavenge the hydroxyl radical efficiently in CytC-VitC radical producing system and its alpha-domain shown more effective potentials than its beta-domain. The electron paramagnetic resonance spectra also show that the alpha-domain has more potential ability for eliminating reactive oxygen free radicals than its beta-domain. The results suggest that GIF could act as an efficient scavenger against free radicals in vitro and the alpha-domain in GIF molecule shows more potential in protecting against reactive oxygen species injury than the beta-domain. 相似文献
14.
Sporopollenin layers in the cell wall of coccal green algae are responsible for the resistance of cell walls to destructive processes during fossilization as well as during chemical preparation of samples for pollen-analysis. Pollen slides of samples from limnic sediments thus also contain some algal cell walls. Although some pollen-analysts tried to stress this fact, the finds of algae in pollen slides have not been paid systematic attention yet, despite their potential use for a more accurate palaeoecological reconstruction. The article summarizes the results of palaeoecological studies showing how the algae can be used in palaeoecological reconstruction of past environments. The possibility of utilizing the indicative value of algal finds is demonstrated on examples of algal communities from fossil, subrecent and recent sediments from different longitudes, latitudes, and altitudes. The identification and indicative values of species and varieties ofPediastrum are included in a special review (Komárek &; Jankovská, Biblioth. Phycol., in press). The contemporary knowledge of ecological requirements of the given taxa, completed by information from their fossil finds, makes possible the reconstruction of trophic and temperature conditions and of the purity of the water environment of the past water biotopes. 相似文献
15.
So Eun Park Jong Cheol Kim Se Jin Lee Mi Rong Lee Sihyeon Kim Dongwei Li Sehyeon Baek Ji Hee Han Jeong Jun Kim Kyung Bon Koo Tae Young Shin Jae Su Kim 《Journal of Asia》2018,21(4):1102-1109
Entomopathogenic fungi have great potential to control agricultural and horticultural insect pests, however optimizing conidial production systems to demonstrate high productivity and stability still needs additional efforts for successful field application and industrialization. Although many virulent entomopathogenic fungal isolates have been viewed as potential candidates in a laboratory environment, very few of the isolates are being used in practice for application in agricultural fields as commercial products. I. javanicus is an entomopathogenic fungus that is parasitic to various diverse coleopteran and lepidopteran insects and thought good candidate as biopesticdes. In this work, the basic characteristics of two entomopathogenic fungi, I. javanica FG340 and Pf04, were investigated in morphological examinations, genetic identification, and virulence against Thrips palmi, and then the feasibility of various grains substrates for conidial production was assessed, particularly focusing on conidial productivity and thermotolerance. Isaria javanica FG340 and Pf04 conidia were solid-cultured on 12 grains for 14?days in a Petri dish. Of the tested Italian millet, perilla seed, millet and barley-based cultures showed high conidial production. The four-grain media yielded >1?×?109 conidia/g of I. javanica FG340 and Pf04. Pf04 strain had enhanced thermotolerance up to 45?°C when cultured on Italian millet. In application, it was easy to make a conidial suspension using the cultured grains, and several surfactants were tested to release the conidia. This work suggests several possible inexpensive grain substrates by which to promote conidial production combined with enhanced stability against exposure to high temperature. 相似文献
16.
17.
Dimorphic and yeast-like mutants of the genusCephalosporium Cda 总被引:1,自引:0,他引:1
E. Jičínská 《Folia microbiologica》1974,19(1):1-4
A series of mutants, in which the mycelial type of growth gradually changes to the dimorphic and permanent yeast-like forms,
were isolated from cultures ofCephalosporium sp. subjected to UV radiation. The intermediate stage between the mycelial and dimorphic strains (mutants 2/29 and 2/R) is
characterized by the absence of aerial hyphae, ability to form conidiophores inside agar and by polymorphism of conidia. The
Y-M transformation of two dimorphic mutants obtained from the 2/R mutant depends on temperature. Another mutant isolated from
the 2/29 strain was found to form the mycelial phase only when osmolarity of the medium increased. At 22°C the transformation
of all three dimorphic strains was influenced by the carbon source: the Y phase predominated in glucose-containing media,
the M phase predominated in media with amino acids or citrate serving as carbon sources. Another mutant (2/7R) was found to
grow permanently in the Y phase and was not influenced by temperature, osmolarity of the medium and by the carbon source.
It is assumed that the dimorphism of the mutants is caused by a conformational mutation inhibiting the apical growth. This
mutation can be phenotypically reversed by some factors of the environment. 相似文献
18.
Soluble microbial products (SMPs) are considered as the main organic components in wastewater treatment plant effluent from
biological wastewater treatment systems. To investigate and explore SMP metabolism pathway for further treatment and control,
two innovative mechanistically based activated sludge models were developed by extension of activated sludge model no.3 (ASM3).
One was the model by combining SMP formation and degradation (ASM3-SMP model) processes with ASM3, and the other by combining
both SMP and simultaneous substrate storage and growth (SSSG) mechanisms with ASM3 (SSSG-ASM3-SMP model). The detailed schematic
modification and process supplements were introduced for comprehensively understanding all the mechanisms involved in the
activated sludge process. The evaluations of these two models were demonstrated by a laboratory-scale sequencing batch reactor
(SBR) operated under aerated/non-aerated conditions. The simulated and measured results indicated that SMP comprised about
83% of total soluble chemical oxygen demand (SCOD) in which biomass-associated products (BAPs) were predominant compared with
utilization-associated products (UAPs). It also elucidated that there should be a minimum SMP value as the reactive time increases
continuously and this conclusion could be used to optimize effluent SCOD in activated sludge processes. The comparative results
among ASM3, ASM3-SMP and SSSG-ASM3-SMP models and the experimental measurements (SCOD, ammonia and nitrate nitrogen) showed
clearly the best agreement with SSSG-ASM3-SMP simulation values (R = 0.993), strongly suggesting that both SMP formation and degradation and SSSG mechanisms are necessary in biologically activated
sludge modeling for municipal wastewater treatment. 相似文献
19.
艾滋病是本世纪80年代初发现的一种烈性传染病,5年病死率为100%,致病因子为人免疫缺陷病毒,该病毒的蛋白酶在病毒复制和成熟中具有决定性的意义。由于目前国内外尚未获得艾滋病病毒蛋白酶的高效表达的重组子及活性检测系统,限制了它的研究与应用。本文利用PCR技术修饰了艾滋病病毒蛋白酶的基因,使其具有便于克隆及表达用的限制酶切位点及转录终止码,井在其C末端设置了一个可用于检验该酶活性的特殊序列。DNA序列分析揭示上述突变策略成功,将修饰后的艾滋病病毒蛋白酶基因克隆入大肠杆菌表达系统,并获得高效表达(>30%),Western-Bolt鉴定结果表明所表达的蛋白为艾滋病病毒所特有,并具有较好的生物活性。 相似文献
20.
云南红豆杉紫杉烷2α-O-苯甲酰转运酶基因的克隆及定性 总被引:1,自引:0,他引:1
通过RACE技术,克隆了云南红豆杉紫杉烷2α-O-苯甲酰转运酶基因(TyTBT),该酶催化2-去苯甲酰-7,13-二乙酰巴卡亭Ⅲ生成7,13-二乙酰巴卡亭Ⅲ,是紫杉醇合成途径中的关键酶之一.TyTBT基因cDNA全长1481 bp,含有1 320 bp的开放读码框,编码440个氨基酸的多肽,分子量为50 050 Da,等电点为6.17.氨基酸序列比对表明TyTBT同植物酰化酶家族的其它成员有较高的相似性,超过67%,同东北红豆杉和曼地亚红豆杉的紫杉烷2α-O-苯甲酰转运酶氨基酸序列的一致性和相似性达到最高,分别为95%和96%.广泛地比对分析证明这种较高的相似性在红豆杉属的其它酶家族中具有普遍性,进化树分析表明同东北红豆杉和曼地亚红豆杉的紫杉烷2α-O-苯甲酰转运酶(TBT)的相似性高于紫杉醇合成途径中的其它酰化酶. 相似文献