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旨在为植物油脱臭馏出物（DD 油）相关标准的制定以及产品的开发提供参考，收集了全球35个不同工厂来源大宗油料的DD油，对其理化指标、不皂化物和危害因子进行分析。结果表明：35个DD油样品的酸值（KOH）为68.1～191.3 mg/g，过氧化值为0.043～0.149 g/100 g，水分及挥发物含量为0.18%～1.98%，灰分含量均小于0.3 g/100 g，皂化值（KOH）为125.0～205.8 mg/g，不皂化物含量为2.80%～35.71%；DD油样品的植物甾醇含量为0.81%～18.23%，维生素E含量为0.13%～9.23%，角鲨烯含量为0.09%～2.56%；DD油样品中PAH4总含量为6.74～61.98 μg/kg，6种邻苯二甲酸酯（DEP、DMP、DIBP、DBP、BBP、DEHP）总含量为1.12～17.57 mg/kg。不同DD油理化指标、维生素E和植物甾醇含量存在较大差异，且样品中多环芳烃和塑化剂的污染水平较高，在DD油相关标准的制定及产品开发的过程中应给予必要的关注。In order to provide reference for the formulation of relevant standards and product development of vegetable oil deodorizer distillate (DD oil), DD oil from 35 different factories around the world was collected and its physicochemical properties, unsaponifiable matter and hazard factors were analyzed. The results showed that the acid value of DD oil samples was 68.1-191.3 mgKOH/g, the peroxide value was 0.043-0.149 g/100 g, the moisture and volatile matter content was 0.18%-1.98%, the ash content was less than 0.3 g/100 g, the saponification value was 125.0-205.8 mgKOH/g, and the unsaponifible matter content was 2.80%-35.71%. The contents of phytosterol and squalene, vitamin E and squalene were 0.81%-18.23%, 0.13%-9.23% and 0.09%-2.56%, respectively. In addition, the total content of PAH4 in DD oil samples was 6.74-61.98 μg/kg, and the total content of six phthalates (DEP, DMP, DIBP, DBP, BBP, DEHP) was 1.12-17.57 mg/kg. The physicochemical properties, vitamin E and phytosterol contents of different DD oil are quite different, and the pollution level of polycycilic aromatic hydrocarbons and plasticizers in the samples is high. Therefore, necessary attention should be paid to the formulation of DD oil related standards and product development.

为了改善天然磷脂的理化性质以及拓宽其应用范围，以辛酸和大豆磷脂为底物，采用酶法对大豆磷脂进行改性。筛选了改性大豆磷脂的脂肪酶，考察了反应温度、反应时间、脂肪酶用量、底物质量比对辛酸结构大豆磷脂改性工艺的影响，在此基础上，采用正交试验优化大豆磷脂的酶法改性工艺条件，并考察了脂肪酶的重复利用性。结果表明：Novozym 435脂肪酶的催化效果优于Lipozyme RM IM和Lipozyme TL IM；大豆磷脂酶法改性的最优条件为反应温度55 ℃、Novozym 435用量25%、底物质量比（辛酸与大豆磷脂质量比）7∶ 1、反应时间36 h，在此条件下辛酸结合率可达（78.79±0.81）%；Novozym 435经过4次重复利用后，辛酸结合率仍能达到（63.67±150）%。综上，Novozym 435可作为催化磷脂改性的优选脂肪酶。In order to improve the physicochemical properties of natural phospholipids as well as to expand their applications, soybean phospholipids were modified by an enzymatic method using octanoic acid and soybean phospholipids as substrates. Lipases for modifying soybean phospholipids were screened, and the effects of reaction temperature, reaction time, lipase dosage and substrate mass ratio on the modification process of octanoic acid-structured soybean phospholipids were investigated. On this basis, orthogonal tests were used to optimize the process conditions of the enzyme-catalyzed modification of soybean phospholipids, and the reusability of the lipases was determined. The results showed that the catalytic effect of Novozym 435 was stronger than that of Lipozyme RM IM and Lipozyme TL IM. The optimal conditions for the enzyme-catalyzed modification of soybean phospholipids were reaction temperature 55 ℃, Novozym 435 dosage 25%, mass ratio of octanoic acid to soybean phospholipids 7∶ 1, and reaction time 36 h. The octanoic acid binding rate was (78.79±0.81)% under the optimal conditions, and the octanoic acid binding rate still reached (63.67±1.50)% after four times of reuse of Novozym 435. In conclusion, Novozym 435 can be used as a preferred lipase to catalyze the modification of phospholipids.

为提高牡丹籽油乳液的氧化稳定性，将叔丁基对苯二酚（TBHQ）与天然抗氧化剂（生育酚、抗坏血酸）进行复配，测定不同抗氧化剂对牡丹籽油乳液的抗氧化作用，并分析了不同复配抗氧化剂的相互作用机制。结果表明：在贮藏30 d时，添加和未添加抗氧化剂牡丹籽油乳液的粒径相较于0 d 均略有增加，200 mg/kg TBHQ与800 mg/kg抗坏血酸复配时乳液的Zeta电位绝对值最大，且抗氧化作用最强；TBHQ与抗坏血酸表现出较好的协同抗氧化作用，与生育酚表现出拮抗作用；TBHQ与生育酚之间拮抗作用的原因主要是TBHQ减少了生育酚在牡丹籽油乳液中油水界面的含量，而TBHQ与抗坏血酸之间协同作用主要是由于抗坏血酸增加了TBHQ在牡丹籽油乳液中油水界面的含量。综上，TBHQ与抗坏血酸复配能提高牡丹籽油乳液的氧化稳定性。In order to improve the oxidative stability of peony seed oil emulsion, tert-butylhydroquinone (TBHQ) was complexed with natural antioxidants (tocopherol and ascorbic acid), and the antioxidant effects of different antioxidants on the peony seed oil emulsion were determined and the mechanism of interaction between the different complexed antioxidants was analyzed. The results showed that the particle size of peony seed oil emulsion with and without antioxidants increased slightly at the 30 d of storage compared with that at the 0 d of storage. The absolute value of the Zeta potential of the emulsion added with 200 mg/kg TBHQ and 800 mg/kg ascorbic acid was the largest and the antioxidant effect was the strongest. TBHQ showed better synergistic antioxidant effect with ascorbic acid, and antagonistic effect with tocopherol. The antagonistic effect between TBHQ and tocopherol was mainly due to the fact that TBHQ reduced the content of tocopherol in the oil-water interface in peony seed oil emulsion, while the synergistic effect between TBHQ and ascorbic acid was mainly due to the fact that ascorbic acid increased the content of TBHQ in the oil-water interface in peony seed oil emulsion. In conclusion, the combination of TBHQ and ascorbic acid can effectively improve the oxidation stability of peony seed oil emulsion.

为给黄油中复配天然抗氧化剂的开发提供思路，通过DPPH法测定DPPH自由基清除率和Rancimat法测定氧化诱导时间，研究单一和复配添加α-生育酚、γ-谷维素和植物甾醇3种天然抗氧化剂对黄油氧化稳定性的影响。结果表明：3种天然抗氧化剂均能提高黄油的氧化稳定性；不同复配组合对黄油氧化稳定性的影响有差异，其中α-生育酚和γ-谷维素（125 mg/kg和1 250 mg/kg）、α-生育酚和植物甾醇（125 mg/kg和1 250 mg/kg）、γ-谷维素和植物甾醇（均为800 mg/kg）3种复配组合对黄油氧化稳定性的提升较大，特别是α-生育酚和γ-谷维素（125 mg/kg和1 250 mg/kg）组合的氧化诱导时间可提升3.70 h，DPPH自由基清除率达80.4%，氧化稳定性能优于其他复配组合。综上，将复配天然抗氧化剂添加到黄油中可提高其氧化稳定性。 To provide ideas for the development of compounded natural antioxidants in butter, DPPH radical scavenging rate was evaluated by DPPH method and oxidation induction time was analyzed by Rancimat method. The effects of single or compound addition of three natural antioxidants, α-tocopherol, γ-oryzanol and phytosterol on oxidative stability of butter were investigated. The results showed that all three natural antioxidants could enhance oxidative stability of butter, and different combinations had different effects on oxidative stability of butter. With the three combinations of α-tocopherol and γ-oryzanol (125 mg/kg and 1 250 mg/kg), α-tocopherol and phytosterol (125 mg/kg and 1 250 mg/kg), and γ-oryzanol and phytosterol (both 800 mg/kg) showed greater improvement in the oxidative stability of butter. In particular, the oxidation induction time of group α-tocopherol and γ-oryzanol (125 mg/kg and 1 250 mg/kg) could be increased by 3.70 h, and the DPPH radical scavenging rate reached 80.4%, and the oxidative stability was better than other combinations. In conclusion, the addition of the compounded natural antioxidants to butter can improve its oxidative stability.

为解决慢性疾病人群适宜摄入脂肪酸比例要求特殊的问题，采用气相色谱法和液质联用法分析结合查阅文献构建17种原料油脂肪酸组成、MCT含量及价格信息数据库，总结某种慢性疾病患者营养要求，建立了一种简便实用的营养调和油数学模型，并基于 MATLAB软件开发易于掌握的求解及评价方法。结果表明：通过运行该程序得到40种符合条件的适宜某种慢性疾病患者食用的营养调和油配方；通过排序优选出10种营养调和油配方。该模型设计合理,可快速准确地计算出各原料油的比例并对配方综合打分评价，实现多种营养调和油配方的生成和排序。 In order to solve the problem of suitable fatty acid intake proportion for chronic patients, a database of fatty acid composition, MCT content and price of 17 kinds of raw oil was established by gas chromatography analysis, LC-MS analysis combined with literature review. The nutritional requirements of patients with certain chronic diseases were summarized, then a simple and practical mathematical model of nutritional blend oil was established, and an easy to master solution and evaluation method was developed based on MATLAB software. The results showed that by running the program, 40 kinds of nutritional blend oil formulas suitable for patients with certain chronic diseases were obtained and 10 kinds of nutritional blend oil formulas were optimized by sequencing. The model is reasonably designed, which can quickly and accurately calculate the proportion of each raw oil and comprehensively score, then evaluate the formulas, so as to realize the generation and sequencing of the formulas of a variety of nutritional blend oils.

Cholesterol 25‐hydroxylase (CH25H), an enzyme involved in cholesterol metabolism, regulates inflammatory responses and lipid metabolism. However, its role in kidney disease is not known. The author found that CH25H transcript is expressed mostly in glomerular and peritubular endothelial cells and that its expression increased in human and mouse diabetic kidneys. Global deletion of Ch25h in Leprdb/db mice aggravated diabetic kidney disease (DKD), which is associated with increased endothelial cell apoptosis. Treatment of 25‐hydroxycholesterol (25‐HC), the product of CH25H, alleviated kidney injury in Leprdb/db mice. Mechanistically, 25‐HC binds to GTP‐binding protein ADP‐ribosylation factor 4 (ARF4), an essential protein required for maintaining protein transport in the Golgi apparatus. Interestingly, ARF4's GTPase‐activating protein ASAP1 is also predominantly expressed in endothelial cells and its expression increased in DKD. Suppression of ARF4 activity by deleting ARF4 or overexpressing ASAP1 results in endothelial cell death. These results indicate that 25‐HC binds ARF4 to inhibit its interaction with ASAP1, and thereby resulting in enhanced ARF4 activity to confer renoprotection. Therefore, treatment of 25‐HC improves kidney injury in DKD in part by restoring ARF4 activity to maintain endothelial cell survival. This study provides a novel mechanism and a potential new therapy for DKD. [ABSTRACT FROM AUTHOR]

N4-acetylcytidine (ac4C) is a modification found in ribonucleic acid (RNA) related to diseases. Expensive and labor-intensive methods hindered the exploration of ac4C mechanisms and the development of specific anti-ac4C drugs. Therefore, an advanced prediction model for ac4C in RNA is urgently needed. Despite the construction of various prediction models, several limitations exist: (1) insufficient resolution at base level for ac4C sites; (2) lack of information on species other than Homo sapiens ; (3) lack of information on RNA other than mRNA; and (4) lack of interpretation for each prediction. In light of these limitations, we have reconstructed the previous benchmark dataset and introduced a new dataset including balanced RNA sequences from multiple species and RNA types, while also providing base-level resolution for ac4C sites. Additionally, we have proposed a novel transformer-based architecture and pipeline for predicting ac4C sites, allowing for highly accurate predictions, visually interpretable results and no restrictions on the length of input RNA sequences. Statistically, our work has improved the accuracy of predicting specific ac4C sites in multiple species from less than 40% to around 85%, achieving a high AUC > 0.9. These results significantly surpass the performance of all existing models. [ABSTRACT FROM AUTHOR]

In order to solve the problem that bearing vibration signal fault feature is difficult to extract effectively under noise, a fault diagnosis method based on Variational Mode Decomposition (VMD) optimized by Cuckoo Search (CS) and Particle Swarm Optimization (PSO) is proposed. The effect of VMD is affected by the number of modes and the penalty parameter. The Levy flight strategy and elimination mechanism of the CS algorithm is added to PSO algorithm and the position updating process is optimized. According to the correlation coefficient and envelope entropy of the Intrinsic Mode Function (IMF), the objective function is constructed to search for the optimal combination of VMD mode number and penalty parameter. The bearing fault type is determined by analyzing the IMF envelope spectrum of the optimal objective function. The fault diagnosis classification task upon the bearing sample data from Case Western Reserve University demonstrates that the proposed CS-PSO algorithm improves the model's classification performance by 5%, which is on average 7.3% higher than other state-of-the-art models. This model can provide an important reference for the accuracy of bearing fault diagnosis. [ABSTRACT FROM AUTHOR]

β(2) adrenergic receptor (β(2)AR) is a prototypical G-protein coupled receptor that stimulates the classic cAMP-protein kinase A (PKA) signaling pathway. Recent studies indicate that the cAMP-PKA activities are spatiotemporally regulated in part due to dynamic association of β(2)AR with phosphodiesterase 4D (PDE4D), a group of cAMP degradation enzymes. Here, we demonstrate that in cardiomyocytes, palmitoylation of β(2)AR, the covalent acylation of cysteine residue 341, plays a critical role in shaping subcellular cAMP-PKA activities in cardiomyocytes via regulating β(2)AR association with arrestin/PDE4D. Replacing cysteine 341 on β(2)AR with alanine (C341A) leads to an impaired binding to β arrestin 2. Surprisingly, the C341A mutant is able to internalize via an arrestin-independent pathway at saturated concentration of agonist stimulation; the internalization becomes caveolae-dependent and requires dynamin GTPase. However, the impaired binding to β arrestin 2 also leads to an impaired recruitment of PDE4D to the C341A mutant. Thus, the mutant C341A β(2)AR is transported alone from the plasma membrane to the endosome without recruiting PDE4D. This alteration leads to an enhanced cytoplasmic cAMP signal for PKA activation under β(2)AR stimulation. Functionally, Mutation of the C341 residue or inhibition of palmitoylation modification of β(2)AR enhances the receptor-induced PKA activities in the cytoplasm and increases in myocyte contraction rate. Our data reveal a novel function of palmitoylation in shaping subcellular cAMP-PKA signaling in cardiomyocytes via modulating the recruitment of β arrestin 2-PDE4D complexes to the agonist-stimulated β(2)AR.

Proteins perform most cellular functions in macromolecular complexes. The same protein often participates in different complexes to exhibit diverse functionality. Current ensemble approaches of identifying cellular protein interactions cannot reveal physiological permutations of these interactions. Here we describe a single-molecule pull-down (SiMPull) assay that combines the principles of a conventional pull-down assay with single-molecule fluorescence microscopy and enables direct visualization of individual cellular protein complexes. SiMPull can reveal how many proteins and of which kinds are present in the in vivo complex, as we show using protein kinase A. We then demonstrate a wide applicability to various signalling proteins found in the cytosol, membrane and cellular organelles, and to endogenous protein complexes from animal tissue extracts. The pulled-down proteins are functional and are used, without further processing, for single-molecule biochemical studies. SiMPull should provide a rapid, sensitive and robust platform for analysing protein assemblies in biological pathways.