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关键词： L-rhamnose   Propionate   Pdu operon   Glycyl radical enzyme   Food biopreservation  

摘要： Lactobacillaceae have a long history as natural or starter cultures in food and produce antimicrobial short-chain carboxylic acids (SCCA) during fermentation. Recently, Loigolactobacillus coryniformis was shown to metabolize the deoxyhexose L-rhamnose to the antifungal SCCA propionate with 1,2-propanediol (1,2-PD) as an intermediate. This study aimed to investigate whether deoxyhexose metabolism is more widespread among food-related Lactobacillaceae. We tested nine Lactobacillaceae species (one strain each) for their ability to produce propionate combining genome analysis with anaerobic cultivation in Hungate tubes. Substrate utilization included ¹³C-labeled L-rhamnose. Bioreactor runs were performed for 72 h at 30 °C and pH 6.5 under aerobic and anaerobic conditions and expression of key genes was monitored. Seven out of nine strains including four Liquorilactobacillus species harbored deoxyhexose metabolism-related genes and produced 1,2-PD. In addition, Latilactobacillus fuchuensis that possessed the pdu operon encoding glycerol/diol dehydratase, and Liquorilactobacillus ghanensis with a gene encoding a glycyl radical enzyme (GRE) formed propionate, which was confirmed by ¹³C-stable isotope probing. In bioreactors, L. ghanensis gre expression and propionate formation were regulated by the presence of oxygen. This study identified new strains that were able to use deoxyhexoses and uncovered a new deoxyhexose utilization pathway in L. ghanensis. Propionate-producing Lactobacillaceae have potential to produce antifungal fermentates for food biopreservation.

摘要： The Global Positioning System (GPS) constellation operates at altitudes that are strongly affected by Earth’s 2:1 gravitational resonance. Unlike the 1:1 resonance, the 2:1 resonance is driven by three dominant harmonic terms of comparable magnitude, which gives rise to more intricate nonlinear dynamics than in the 1:1 resonance. The dynamical models adopted in this work incorporate $J_2$, the three dominant terms of 2:1 resonance, Poynting–Robertson drag, and lunisolar secular perturbations. Based on these models, the resonance width, the equilibrium semi-major axis, and Fast Lyapunov Indicator maps in the resonant angle and semi-major axis phase plane are computed as functions of the initial orbital elements. These indicators reveal the domains of influence of the three dominant terms of 2:1 resonance, as well as the shapes of the resonance islands. The Poynting–Robertson drag, in turn, drives a slow but secular decay of the semi-major axis, causing orbits to drift quasi-statically across the resonant region. As a result, space debris initially above the resonant region is gradually brought into the 2:1 resonance zone, where it may undergo long-term resonant capture, or experience resonant jumps. For space debris located near GPS altitudes with high area-to-mass ratios, the combined action of the 2:1 resonance and the lunisolar secular resonances leads to simultaneous capture into the 2:1 resonance and the lunisolar secular resonance. These results characterize the resonant features of the 2:1 resonance, quantify how resonant capture and resonant jumps depend on the initial orbital elements, and provide new insights into the potential role of the 2:1 resonance in debris mitigation and orbit maintenance strategies in the GPS altitude region.

关键词： TANK结合激酶1(TBK1)   核因子κB激活激酶   CiteSpace   Web of Science   文献计量学   可视化   共被引   研究热点   前沿  

摘要： 背景:肿瘤双向调控因子核因子κB激活激酶的研究成果逐年增多,但是却没有相关文献计量学分析。目的:通过文献计量学分析肿瘤逃避因子核因子κB激活激酶的研究现状、热点及趋势。方法:基于Web of Science核心合集中的SCIE数据库筛选近10年来核因子κB激活激酶相关研究文献,导入Cite Space 6.3.R1软件中分别以国家(地区)、作者、机构、参考文献和关键词5个选项进行文献计量及可视化分析,并运用Origin 2021软件绘制相关统计图。结果与结论:核因子κB激活激酶的发文量、文献共被引次数呈现上升的趋势,Chen,Dan-Dan、Gui,Jian-Fang、Qin,Qiwei和Li,Shun 4位作者发文量最多(11篇),中国科学院、中国科学院大学、浙江大学、中国农业科学院、武汉大学的发文量较大(>50篇)。近10年来关于核因子κB激活激酶的研究热点主要集中在innate immunity、c GAS-STING pathway、NF-κB、inflammation、optineurin、expression、cancer等模块。结果表明,近年来各国学者在相关领域进行了持续且深入的研究,核因子κB激活激酶在自身免疫系统、信号通路、基因表达、肿瘤防治等方面显示出巨大的科研潜力。但是学者之间、机构之间的学术合作并不紧密,今后学者应加强合作与交流,把握核因子κB激活激酶的研究热点与趋势,拓展在疾病领域中的研究范围,为进一步阐明疾病的药效机制和病理变化提供更多证据。

关键词： Immune checkpoint blockade   Immunogenic cell death   Ferroptosis   Calcium overload   Metal-polyphenol network   Thyroid cancer  

摘要：

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  An innovative PEI "electrostatic bridge" strategy enables robust HA coating on negatively charged MPNs, overcoming interfacial repulsion for enhanced tumor targeting and lysosomal escape.
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  The CaO₂@MPN-HA nanoreactor degrades in the TME, enabling self-supplied H₂O₂, Fe²⁺/Fe³ ⁺ cycling, and Ca²⁺ burst to synergistically amplify oxidative stress via ferroptosis and calcium overload.

关键词： Engeletin   Hepatic fibrosis   Inflammation   Oxidative injury   Risperidone  

摘要： Risperidone (RIS) is a potent atypical antipsychotic drug that has gained widespread attention owing to its toxic effects on the body organs such as liver. The current research experiment was executed to elucidate the alleviative efficacy of engeletin (ENG) against risperidone (RIS) induced hepatic dysfunction. Thirty-six Sprague Dawley rats were divided into four groups including control, RIS (2 mg/kg), RIS (2 mg/kg) + ENG (10 mg/kg), and ENG (10 mg/kg) alone administered group for 10 weeks orally. RIS intoxication induced hepatic fibrosis as well as inflammation via upregulating the gene expression of transforming growth factor beta receptor 2 (TGFBR2), transforming growth factor beta receptor 1 (TGFBR1), nuclear factor- kappa B (NF-κB), transforming growth factor beta-1 (TGF-β1), collagen type I alpha 1 (COL1A1), tumor necrosis factor-alpha (TNF-α), SMAD3, cyclooxygenase-2 (COX-2), interleukin-6 (IL-6), SMAD4 & interleukin-1beta (IL-1β). The administration of RIS promoted the levels of ROS and MDA while diminishing the activities of HO-1, GPx, SOD, GSR, CAT and GST. RIS intakes abruptly uplifted levels of gamma-glutamyl transferase (GGT), alanine aminotransferase (ALT), aspartate aminotransferase (AST), & alkaline phosphatase (ALP) while lowering the concentrations of albumin & total proteins in hepatic tissues. RIS exposure promoted the levels of Caspase-3, Bax & Caspase-9 while demolishing levels of Bcl-2. RIS intoxication dysregulated the normal architecture of hepatic tissues. Nonetheless, ENG therapy ameliorated hepatic dysregulations owing to its antioxidative, anti-inflammatory, anti-fibrotic as well as anti-apoptotic properties. In addition, advanced molecular docking analysis demonstrated strong binding affinity of engeletin with the key regulatory proteins SMAD3 (−9.3 kcal/mol) and NF-κB p65 (−9.1 kcal/mol), providing strong evidence that ENG can directly interact with the central regulators of the TGF-β1/Smad and NF-κB signaling pathway

关键词： MIRI   MARCHF6   Ferroptosis   Ubiquitination   ADAMTS4   SDC-1  

摘要：

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  Reports indicate that MARCHF6 can regulate ferroptosis.
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  The high expression of MARCHF6 alleviates myocardial ischemia-reperfusion injury.
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  Elevated MARCHF6 expression inhibits ferroptosis in CMECs.
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  MARCHF6 regulates ferroptosis through the ADAMTS4/SDC-1 pathway.
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  MARCHF6 is a promising therapeutic target for MIRI.

摘要： The present paper reports investigation of elastic, mechanical, thermal, and ultrasonic features of B4 ternary alloy Ga_xAl_1-xN (0≤ x ≤ 1.0) at T = 300K. The second- and third-order elastic constants (SOECs and TOECs) were enumerated using the Lennard-Jones potential to judge the elastic stability of the selected alloys at 300 K. Pugh's ratio and Poisson's ratio show that all alloys display brittleness. The reducing trend of ultrasonic wave velocity with rising gallium concentration provides an indication of progressive lattice softening. The Debye characteristic temperature, thermal conductivity and relaxation time were assessed from elastic constants and ultrasonic velocities to explore the ultrasonic attenuation of the selected alloys. The semiconducting nature of the selected alloys has been confirmed by 10⁻¹¹ s order of the relaxation time. The machine learning algorithms, namely Random Forest and XGBoost have been utilized for comparative performance analysis across various statistical metrices. It is clear from the observed trends that XGBoost performs stable and better conditions in maximum situations, as manifest from the lower fault values and smoother differences.The scatter plot investigation provides information about the strong pact between forecasted and observed values. The theoretical results are in consistent with the existing computational and experimental data, validating the applied theoretical model.

关键词： Tributyltin   Histopathology   Ultrastructural adrenal structure   HMGB1/Beclin-1/NF-κB signals   Rats  

摘要：

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  TBT induces reversible adrenocortical toxicity via occurrence of hormonal disturbance in rats.
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  TBT results in oxidative stress, HMGB-1/ NF-κB signaling, and autophagy, with incomplete recovery after 4 weeks.
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  TBT results in histopathological, ultrastructural, and immunohistochemical alterations.
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  A 4-week recovery period partially reversed these changes.

关键词： Keggin-型杂多阴离子   质子化结构   光谱性质   密度泛函理论   遗传算法  

摘要： Keggin-型杂多酸作为高效光催化剂在能源催化转换领域扮演重要角色.虽然在实验上利用它们较为容易实现光催化反应,然而要对相关的光催化反应机理进行原子水平细节研究仍然困难重重,在其中获得一个相对合理的催化剂团簇模型至关重要.本文利用自建的遗传算法程序并结合密度泛函理论探究Keggin-型铌杂多阴离子完全质子化团簇(H_(n+3)[PMo_(12-n)Nb_(n)O_(40)],n=1~4)的稳定几何结构与光谱性质.通过观察铌作为杂原子取代团簇表面上的钼以及质子占据对体系几何结构和光谱性质的影响,我们期望能够为基于该类团簇的光催化剂分子设计以及光催化反应机理探究提供有用信息.基于计算数据,我们发现:在优化团簇几何结构中,随着杂Nb原子数目的增多,它们在团簇骨架上的分布能展现一定的规律(倾向于离散分布或者共用O桥而成等边三角形),并且质子均倾向于与杂Nb原子(或其邻居)相联的端基O成单键.团簇体系的偶极矩从最大值出发降到最低值而后逐渐增大.这可以被归功于杂原子铌与被取代原子钼之间相对较小的电负性差异以及取代位置模式的不同.研究体系的红外(或拉曼)吸收主要分布在两个波数区间(0~1500 cm^(-1))以及(3600~4000 cm^(-1)).前者对应于团簇骨架上重原子间(桥基O-Mo,O-Nb等)或者骨架局部关联的振动模式,后者对应于端基的O-H单键的振动模式.同时,它们在1200~1500cm^(-1)波数区间展现可区分的红外吸收分布,在高波数区间Raman吸收可展现强度差异.

关键词： 1,4-butanediol   Cu catalysts   Dehydrocyclization   Spinel structure   γ-butyrolactone  

摘要： Gas-phase dehydrocyclization of 1,4-butanediol (BDO) is an environmentally benign and sustainable route for γ-butyrolactone (GBL) production. In this work, a series of Cu-M (M = Zn, Cr) catalysts was synthesized via coprecipitation and evaluated in a fixed-bed reactor for GBL yield. Under the reaction conditions of 240 °C, 0.1 MPa, and a weight hourly space velocity (WHSV) of 2 mL∙g⁻¹∙h⁻¹, 99.62% of BDO conversion, 99.72% of GBL selectivity, and 2.22 mol_GBL·g_catalyst^-1·h⁻¹ of CBL formation rate were achieved over CuZnCr-600 catalyst, which is higher than reported studies. Long-term test proved that this catalyst could operate over 100 h without any deactivation. Combined microscopic and spectroscopic analysis showed that the calcination conditions affected the surface acidity-basicity of catalysts by changing the CuO content and the strength of the Cr-O bond. The Cu-M compositions significantly influenced the morphology and the electronic properties of Cu species. The incorporation of Cr led to the formation of CuCr₂O₄ spinel structure, which not only enhanced Cu dispersion but also improved the catalysts’ resistance to sintering. The presence of Zn restrained the phase-transformation of CuCr₂O₄ from cubic to tetragonal, which ensured the reducible property of CuCr₂O₄ even under high-temperature calcination. Furthermore, modulating the calcination temperature and the Cu-M compositions maintained an optimal Cu⁺/Cu⁰ ratio under reaction conditions. All these issues contributed to the high yield of GBL and the prolonged lifetime of catalysts.