Dynamic and Reversible Aggregation of the Human CAP Superfamily Member GAPR-1 in Protein Inclusions in Saccharomyces cerevisiae

Many proteins that can assemble into higher order structures termed amyloids can also concentrate into cytoplasmic inclusions via liquid–liquid phase separation. Here, we study the assembly of human Golgi-Associated plant Pathogenesis Related protein 1 (GAPR-1), an amyloidogenic protein of the Cysteine-rich secretory proteins, Antigen 5, and Pathogenesis-related 1 proteins (CAP) protein superfamily, into cytosolic inclusions in Saccharomyces cerevisiae. Overexpression of GAPR-1-GFP results in the formation GAPR-1 oligomers and fluorescent inclusions in yeast cytosol. These cytosolic inclusions are dynamic and reversible organelles that gradually increase during time of overexpression and decrease after promoter shut-off. Inclusion formation is, however, a regulated process that is influenced by factors other than protein expression levels. We identified N-myristoylation of GAPR-1 as an important determinant at early stages of inclusion formation. In addition, mutations in the conserved metal-binding site (His54 and His103) enhanced inclusion formation, suggesting that these residues prevent uncontrolled protein sequestration. In agreement with this, we find that addition of Zn²⁺ metal ions enhances inclusion formation. Furthermore, Zn²⁺ reduces GAPR-1 protein degradation, which indicates stabilization of GAPR-1 in inclusions. We propose that the properties underlying both the amyloidogenic properties and the reversible sequestration of GAPR-1 into inclusions play a role in the biological function of GAPR-1 and other CAP family members.     

炎症因子相关基因在创伤失血性休克中的研究进展

近年来研究认为在创伤失血性休克的发生发展及液体复苏、缺血再关注过程中均伴随着炎症因子的变化,现将与炎症因子密切相关基因环氧化酶-2(COX-2)、核因子κB(NF-κB)、诱导型一氧化氮合酶(iNOS)、高迁移率族蛋白1(HMGB1)、低氧诱导因子1α(HIF1α)、血红素氧合酶-1(HO-1)、寒冷诱导的RNA结合蛋白(CIRBP)在创伤失血性休克中的作用机制方面的研究及进展作一综述,为创伤失血性休克临床救治提供思路。     

Stem cells: Insights into the secretome

Stem cells have been considered as possible therapeutic vehicles for different health related problems such as cardiovascular and neurodegenerative diseases and cancer. Secreted molecules are key mediators in cell–cell interactions and influence the cross talk with the surrounding tissues. There is strong evidence supporting that crucial cellular functions such as proliferation, differentiation, communication and migration are strictly regulated from the cell secretome. The investigation of stem cell secretome is accumulating continuously increasing interest given the potential use of these cells in regenerative medicine. The scope of the review is to report the main findings from the investigation of stem cell secretome by the use of contemporary proteomics methods and discuss the current status of research in the field. This article is part of a Special Issue entitled: An Updated Secretome.     

Lack of SMALL ACIDIC PROTEIN 1 (SMAP1) causes increased sensitivity to an inhibitor of RUB/NEDD8-activating enzyme in Arabidopsis seedlings

SMALL ACIDIC PROTEIN 1 (SMAP1) functions upstream of the degradation of AUX/IAA-proteins in the response to 2,4-dichlorophenoxyacetic acid and physically interacts with the COP9 SIGNALOSOME (CSN). Also, its function is linked to RELATED TO UBIQUITIN (RUB) modification. To further investigate the relationship between SMAP1 and the RUB modification system, we examined the effect of MLN4924, an inhibitor of RUB/NEDD8-activating E1 enzyme, on the growth of Arabidopsis thaliana. We found that the anti-auxin resistant 1 mutants, which lack SMAP1, are more sensitive to MLN4924 than wild type and that SMAP1 is responsible for this hypersensitivity. This new evidence supports our previous speculation that SMAP1 acts in Cullin-RING ubiquitin E3 ligase regulated signaling processes via its interaction with components associated with the RUB modification system.     

带状疱疹并发神经痛患者危险因素的相关研究

目的:探讨带状疱疹患者并发神经痛患者的相关危险因素.方法:采用回顾性分析的方法,对我院100例合并带状疱疹后神经痛(PHN)患者年龄、性别、患病后初诊日、急性期发作频度、急性期疼痛程度、疱疹部位、疼痛的性质等进行统计,并进行多因素Logistic相关分析.结果:不同年龄、性别、及疼痛评分间PHN患病率间差异有统计学意义(P＜0.05或P＜0.01).而患病后初诊日及急性期发作频度、不同疱疹部位的PHN患病率、不同疼痛性质的PHN患病率差异无统计学意义(P＞0.05).Logistic相关分析显示,年龄、性别、不同疼痛程度与PHN患病率存在一定的相关性,相关P值分别为0.003、0.002、0.005,均P＜0.01.结论:年龄、性别、不同疼痛程度可影响PHN的发生.针对急性期PHN患者,应早发现,早治疗,提高患者生活质量.     

Characterization of the C584R variant in the mtDNA depletion syndrome gene FBXL4, reveals a novel role for FBXL4 as a regulator of mitochondrial fusion

Mutations in FBXL4 (F-Box and Leucine rich repeat protein 4), a nuclear-encoded mitochondrial protein with an unknown function, cause mitochondrial DNA depletion syndrome. We report two siblings, from consanguineous parents, harbouring a previously uncharacterized homozygous variant in FBXL4 (c.1750 T > C; p.Cys584Arg). Both patients presented with encephalomyopathy, lactic acidosis and cardiac hypertrophy, which are reported features of FBXL4 impairment. Remarkably, dichloroacetate (DCA) administration to the younger sibling improved metabolic acidosis and reversed cardiac hypertrophy. Characterization of FBXL4 patient fibroblasts revealed severe bioenergetic defects, mtDNA depletion, fragmentation of mitochondrial networks, and abnormalities in mtDNA nucleoids. These phenotypes, observed with other pathogenic FBXL4 variants, confirm the pathogenicity of the p.Cys584Arg variant. Although treating FBXL4 fibroblasts with DCA improved extracellular acidification, in line with reduced lactate levels in patients, DCA treatment did not improve any of the other mitochondrial functions. Nonetheless, we highlight DCA as a potentially effective drug for the management of elevated lactate and cardiomyopathy in patients with pathogenic FBXL4 variants. Finally, as the exact mechanism through which FBXL4 mutations lead to mtDNA depletion was unknown, we tested the hypothesis that FBXL4 promotes mitochondrial fusion. Using a photo-activatable GFP fusion assay, we found reduced mitochondrial fusion rates in cells harbouring a pathogenic FBXL4 variant. Meanwhile, overexpression of wildtype FBXL4, but not the p.Cys584Arg variant, promoted mitochondrial hyperfusion. Thus, we have uncovered a novel function for FBXL4 in promoting mitochondrial fusion, providing important mechanistic insights into the pathogenic mechanism underlying FBXL4 dysfunction.     

液体负平衡对腹部外伤患者血流动力学指标变化与炎症因子浓度的影响及其相关因素分析

目的:探讨液体负平衡对腹部外伤患者血流动力学指标变化与炎症因子浓度的影响并分析其相关因素。方法:选取2015年10月-2018年9月期间在我院接受治疗的腹部外伤患者120例,以随机数字表法分为对照组(n=60)和研究组(n=60)。对照组患者采用常规的抗感染的治疗方法,研究组患者在对照组患者的基础上保持该组患者的液体负平衡,比较两组患者炎症因子水平、血流动力学指标、体内氧合情况及呼吸机机械通气状况,多因素Logistic回归分析研究组患者的生存率的影响因素。结果:两组患者治疗后白介素-6(IL-6)、动脉血氧分压差[P(A-a)O2]均降低,且研究组低于对照组(P0.05),动脉血氧分压(PaO2)升高,且研究组高于对照组(P0.05)。两组患者脱机时平台压(Pplat)、呼气末正压(PEEP)、吸氧浓度(Fi O2)均降低,且研究组低于对照组(P0.05)。两组患者治疗后血管外肺水(EVLWI)降低,且研究组低于对照组(P0.05),心输出量(CO)、心指数(CI)与治疗前比较无差异(P0.05)。单因素分析结果显示,研究组患者生存率与患者的年龄、腹部创伤严重度评分(ISS)、手术前体温和碱剩余(BE)绝对值、ICU入室体温有关(P0.05),而与手术时间无关(P0.05)。Logistic回归分析结果显示,年龄、ISS、手术前BE绝对值、ICU入室体温均是研究组患者生存率的影响因素。结论:液体负平衡对腹部外伤患者的心肺功能具有一定的改善作用,可降低患者体内炎症因子的水平。年龄、ISS、ICU入室体温以及手术前BE绝对值均会影响腹部外伤患者的生存率。     

双嘧达莫联合头孢呋辛对川崎病患儿WBC、PLT、ESR水平的影响

摘要 目的：研究双嘧达莫联合头孢呋辛对川崎病患儿白细胞（white blood cell,WBC）、血小板（blood platelet,PLT）、红细胞沉降率(erythrocyte sedimentation rate,ESR)水平的影响。方法：选择2015年1月～2019年12月我院（西安交通大学附属儿童医院）收治的71例川崎病患儿,随机分为两组。对照组服用头孢呋辛治疗,每次10 mg／kg,每天2次,持续给药14 d或直至患儿退热后7 d为止。观察组在头孢呋辛的基础上,加服双嘧达莫,剂量为每天3～5 mg/kg,分成3次服用,持续给药两个月。检测两组治疗前后的抗血小板聚集相关因子和血清炎症因子的变化。结果：观察组川崎病患儿的有效率明显高于对照组(P<0.05);治疗后,两组患儿的WBC、PLT和ESR水平均明显降低(P<0.05),且观察组患儿的WBC、PLT和ESR水平明显低于对照组(P<0.05);观察组川崎病患儿颈淋巴结肿胀、发热、黏膜弥漫性充血、结膜充血、躯干红斑等症状的缓解时间均明显短于对照组(P<0.05);治疗后,两组患儿的血清H血清高迁移率族蛋白B1（High mobility group protein B1,HMGB1）、肿瘤坏死因子（Tumor necrosis factor,TNF）-α、巨噬细胞移动抑制因子（Macrophage migration inhibitory factor,MIF）和白介素-6（Interleukin -6,IL-6）水平均明显降低(P<0.05),且观察组患儿的血清HMGB1、TNF-α、MIF和IL-6水平明显低于对照组(P<0.05)。结论：双嘧达莫联合头孢呋辛能有效抑制川崎病患儿的血小板聚集,提高治疗有效率,降低炎性因子水平,减轻临床症状,值得推广。