Human α defensins promote the expression of the inflammatory cytokine interleukin‐8 under high‐glucose conditions: Novel insights into the poor healing of diabetic foot ulcers

Sustained infection and chronic inflammation are the most common features and complex mechanisms of diabetic foot disease. In this study, we examined the expression and functional roles of human endogenous α defensins in diabetic foot ulcer. The expression levels of human α defensins HNP1, HNP3, and HNP4 were significantly higher in the wound center than the edge of diabetic foot ulcers. And the inflammatory cytokine interleukin IL‐8 (IL‐8) was also highly expressed in wound exudates. In human foreskin fibroblasts, these human α defensins were found only slightly to affect IL‐8 expression directly. hemoglobin A1C (HbA1c) is the main clinical indicator of diabetic foot disease. Advanced glycation end products of bovine serum albumin (AGE‐BSA), as HbA1c analogue, was found to promote IL‐8 expression. Human α defensins, in the presence of AGE‐BSA, further significantly promoted IL‐8 expression. These findings showed that human α defensins aggravated the inflammatory response in diabetic foot ulcers patients, providing new insights in to the poor healing of diabetic foot ulcers.     

Autophagy–virus interplay in plants: from antiviral recognition to proviral manipulation

Autophagy is a conserved self-cleaning and renewal system required for cellular homeostasis and stress tolerance. Autophagic processes are also implicated in the response to ‘non-self’ such as viral pathogens, yet the functions and mechanisms of autophagy during plant virus infection have only recently started to be revealed. Compelling evidence now indicates that autophagy is an integral part of antiviral immunity in plants. It can promote the hypersensitive cell death response upon incompatible viral infections or mediate the selective elimination of entire particles and individual proteins from compatible viruses in a pathway similar to xenophagy in animals. Several viruses, however, have evolved measures to antagonize xenophagic degradation or utilize autophagy to suppress disease-associated cell death and other defence pathways like RNA silencing. Here, we highlight the current advances and gaps in our understanding of the complex autophagy–virus interplay and its consequences for host immunity and viral pathogenesis in plants.     

肠道菌群失衡对乙型肝炎相关慢加急性肝衰竭患者 血浆降钙素原升高的影响

目的探讨肠道菌群失衡对乙型肝炎相关慢加急性肝衰竭(hepatitis B virus-related acute-on-chronic liver failure,HBV-ACLF)患者血浆降钙素原(procalcitonin,PCT)水平升高的影响。方法检测29例HBV-ACLF(肝衰组)、14例慢性乙型肝炎(乙肝组)患者入院时的血浆PCT、内毒素(endotoxin,LPS)水平,收集患者新鲜尾便并通过高通量测序检测肠道菌群状况,统计分析两组患者间肠道菌群、B/E值、PCT和LPS水平的差异,以及肝衰组患者PCT、LPS、B/E值三者间的相关性。结果与乙肝组患者比较,肝衰组厚壁菌门、放线菌门、双歧杆菌属、乳杆菌属等肠道细菌显著减少,而拟杆菌门、变形菌门、埃希菌属等肠道细菌过度生长,两组患者间各菌群比较差异均具有统计学意义(t=-4.84,Z=-2.84,Z=-2.57,Z=-4.39,t=3.59,t=2.64,t=2.19,P0.01、0.01、=0.01、0.01、0.01、=0.01、=0.04);肝衰组PCT[0.50(0.96)]ng/mL、LPS(0.46±0.10)EU/mL、B/E值(0.04±0.01),乙肝组PCT(0.08±0.02)ng/mL、LPS(0.05±0.02)EU/mL、B/E值(1.62±0.31),各指标两组间比较差异均具有统计学意义(Z=-3.17,t=5.88,t=16.18,P0.01、0.01、0.01);肝衰组B/E值与LPS水平呈负相关关系(r=-0.81,P0.01),B/E值与PCT水平呈负相关关系(r=-0.79,P0.01),且PCT水平与LPS呈正相关关系(r=0.76,P0.01)。结论 HBV-ACLF患者肠道菌群失衡导致肠源性LPS生成增多,而肠源性LPS促使PCT产生增多。     

儿童乙型流感病毒感染特点及防治的研究进展

乙型流感病毒是引起流行性感冒(简称流感)发生和流行的主要病原体之一,近年来流感高发的季节感染率呈上升趋势,儿童是乙型流感病毒感染的易感、高危群体。乙型流感病毒虽然抗原变异性较弱,但仍可引起暴发流行,严重威胁患儿的健康,因此对于儿童乙型流感病毒感染的防治至关重要。本文综合近年来国内外相关文献,从流行病学特征、临床表现、实验室检查、乙型流感病毒感染的药物治疗、免疫疗法等角度出发对乙型流感病毒感染特点及治疗进展予以综述,对乙型流感病毒进行长期有效的监测,了解儿童乙型流感病毒的感染特点,为儿童乙型流感的预防及临床诊断与防治提供理论参考。     

黔产昆明山海棠化学成分及其抑菌活性研究

该研究采用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、半制备型高效液相色谱和重结晶等方法分离纯化,从黔产昆明山海棠乙醇提取物中分离得到11个化合物,并采用96孔板微量稀释法对化合物进行抑菌活性测定。结果表明:利用NMR,MS等现代波谱技术以及化合物的理化性质并结合参考文献分别鉴定为3-O-乙酰基齐墩果酸(1),雷酚萜(2),3-氧代齐墩果酸(3),β-谷甾醇(4),木栓酮(5),β-谷甾醇棕榈酸酯(6),雷公藤红素(7),大黄素(8),雷公藤内酯甲(9),雷藤二萜醌B(10),ent-kauran-16β,19-diol(11)。抑菌活性结果显示,化合物3、7和8具有较好的抑菌作用,MIC值为2~16μg·mL-1。其中,化合物6、11为首次从该植物中分离得到,化合物11为首次从雷公藤属植物中分离得到,且首次发现了化合物3、7对绿脓杆菌和青枯菌具有明显的抑制作用。     

NEK5 regulates cell cycle progression during mouse oocyte maturation and preimplantation embryonic development

NEK5, a member of never in mitosis‐gene A‐related protein kinase, is involved in the regulation of centrosome integrity and centrosome cohesion at mitosis in somatic cells. In this study, we investigated the expression and function of NEK5 during mouse oocyte maturation and preimplantation embryonic development. The results showed that NEK5 was expressed from germinal vesicle (GV) to metaphase II (MII) stages during oocyte maturation with the highest level of expression at the GV stage. It was shown that NEK5 localized in the cytoplasm of oocytes at GV stage, concentrated around chromosomes at germinal vesicle breakdown (GVBD) stage, and localized to the entire spindle at prometaphase I, MI and MII stages. The small interfering RNA‐mediated depletion of Nek5 significantly increased the phosphorylation level of cyclin‐dependent kinase 1 in oocytes, resulting in a decrease of maturation‐promoting factor activity, and severely impaired GVBD. The failure of meiotic resumption caused by Nek5 depletion could be rescued by the depletion of Wee1B. We found that Nek5 depletion did not affect CDC25B translocation into the GV. We also found that NEK5 was expressed from 1‐cell to blastocyst stages with the highest expression at the blastocyst stage, and Nek5 depletion severely impaired preimplantation embryonic development. This study demonstrated for the first time that NEK5 plays important roles during meiotic G2/M transition and preimplantation embryonic development.     

南极假丝酵母脂肪酶B在离子液体/超临界流体体系中的稳定性模拟

脂肪酶在离子液体/超临界流体体系中的结构稳定性是影响其活性的重要因素。本文采用分子动力学方法分别研究了南极假丝酵母脂肪酶B(CALB)在离子液体CYPHOS IL-201/极性超临界流体CHF_3两相体系和离子液体CYPHOS IL-201/非极性超临界流体CO_2两相体系中的结构稳定性,揭示影响CALB结构稳定性的因素。研究结果表明,在超临界CHF_3中,CHF_3破坏蛋白维持α螺旋结构的氢键是蛋白结构不稳定的主要原因;在超临界CO_2中,CALB蛋白的结构紧密性降低,有序二级结构发生了变化,导致稳定性下降。离子液体和两种超临界流体均形成了两相体系,蛋白处于离子液体相中,离子液体不溶于超临界流体,但超临界流体部分进入离子液体相,降低了离子液体相的黏度。其中,相比于CYPHOS IL-201/CO_2体系,CYPHOS IL-201/CHF_3体系的黏度降低多。在离子液体CYPHOS IL-201与超临界流体(CHF_3、CO_2)形成的两相体系中,离子液体CYPHOS IL-201具有保护蛋白结构的作用,使CALB蛋白结构更加稳定。     

荧光物质(MFA、MFB)的分离、结构鉴定及金华地区高产菌株的筛选

采用硅胶柱层析及制备型液相色谱仪对红曲米中两种荧光物质进行分离纯化,使用高效液相色谱法(HPLC)检测荧光物质纯度,然后使用高分辨质谱(ESI-HRMS)对两种荧光物质进行分析,得到两种荧光物质的分子量分别为356和384,ESI-MS/MS二级质谱把两者鉴定为monasfluore A (MFA)和monasfluore B (MFB);从金华地区红曲米中分离得到10株红曲菌株,经固态发酵采用HPLC法分析,筛选获得1株高产MFA、MFB的菌株WZWZ,该菌株发酵制得红曲米中MFA含量为3.63 g/kg,MFB含量为7.29 g/kg,对WZWZ菌株进行外观形态学及显微观察、ITS基因序列测定与分析,最终将菌株WZWZ鉴定为紫色红曲霉(Monascus purpureus)。     

A Persistence Detector for Metabolic Network Rewiring in an Animal

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