phospholipid

磷脂
  • 文章类型: Journal Article
    细菌接合是DNA从供体细胞单向转移至受体细胞的过程。它是抗生素抗性基因在细菌种群中传播的主要手段。它关键取决于细胞外附件的形成,称为“菌毛,“通过称为共轭的”IV型分泌系统的大型跨膜分泌系统。“在这里,我们介绍了由R388质粒编码的接合菌毛的结构。我们证明,与迄今为止用于低温电子显微镜(cryo-EM)结构测定的所有共轭菌毛相反,受体细胞的存在极大地刺激了R388质粒编码的接合菌毛。将其冷冻EM结构与现有的共轭菌毛结构进行比较,突出了R388菌毛结构与其同系物之间的许多重要差异,最突出的是其结合脂质的高度独特的构象。
    Bacterial conjugation is a process by which DNA is transferred unidirectionally from a donor cell to a recipient cell. It is the main means by which antibiotic resistance genes spread among bacterial populations. It is crucially dependent upon the elaboration of an extracellular appendage, termed \"pilus,\" by a large double-membrane-spanning secretion system termed conjugative \"type IV secretion system.\" Here we present the structure of the conjugative pilus encoded by the R388 plasmid. We demonstrate that, as opposed to all conjugative pili produced so far for cryoelectron microscopy (cryo-EM) structure determination, the conjugative pilus encoded by the R388 plasmid is greatly stimulated by the presence of recipient cells. Comparison of its cryo-EM structure with existing conjugative pilus structures highlights a number of important differences between the R388 pilus structure and that of its homologs, the most prominent being the highly distinctive conformation of its bound lipid.
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  • 文章类型: Journal Article
    癌症被列为全球死亡率最高的癌症之一,对其治疗提出了重大挑战,特别是当使用常规化疗方法时。相反,由于与当代医学策略相比,草药缺乏副作用,因此人们对使用草药作为癌症治疗的替代方法越来越感兴趣。由于纳米技术在治疗各种疾病方面的功效,将纳米技术纳入治疗引起了人们的关注。通过增强载体内的药物和纳米结构的特性以实现靶向药物递送,植物体在癌症的治疗中起着至关重要的作用。磷脂分子和植物生物活性化合物之间化学键的建立确保了植物体的稳定性,从而将它们确立为将植物衍生成分运输到特定区域的药物递送系统的创新机制。这个迷你概述讨论了潜在的植物体复合物,uses,缺点,专利,挑战,以及植物体在癌症治疗中的前景。因此,许多包含植物来源成分的植物体制剂已显示出有希望的抗癌特性,目前正在进行临床试验的几种配方。
    Cancer is classified as having one of the highest mortality rates on a global scale, presenting a significant challenge in its treatment, especially when conventional chemotherapy methodologies are used. Conversely, there is a growing interest in utilizing herbal medicine as an alternative to the treatment of cancer because of its lack of adverse effects compared to contemporary medical strategies. The incorporation of nanotechnology into therapy has attracted attention owing to its efficacy in the treatment of various illnesses. Phytosomes play a crucial role in the treatment of cancer by enhancing the characteristics of drugs and nanostructures within carriers to enable targeted drug delivery. The establishment of chemical bonds between phospholipid molecules and bioactive compounds from plants ensures the stability of phytosomes, thus establishing them as an innovative mechanism for drug delivery systems that transport plant-derived constituents to specific areas. This mini-overview discusses the potential phytosome complexes, uses, drawbacks, patents, challenges, and prospects of phytosomes in cancer treatment. Thus, numerous phytosomal formulations incorporating plant-derived components have exhibited promising anticancer properties, with several formulations currently undergoing clinical trials.
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  • 文章类型: Journal Article
    背景:;因子(F)V在促凝血和抗凝血机制中都至关重要。本报告描述了FV缺陷患者的新F5突变(FV:C6IU/dL,FV:Ag32IU/dL),并发复发性深静脉血栓。患者表现出活化的蛋白C抗性(APCR),具有由FV-Y1961C(FVKanazawa)和FV-1982_1983del组成的复合杂合突变。目的:阐明与这种FV异常相关的血栓形成机制。
    结果:在我们使用HEK293T细胞的表达实验中,FV-1982_1983del的水平低于检测灵敏度,分析是有针对性的,因此FV-Y1961C突变。基于APTT的凝血试验表明FV-Y1961C表现出APCR,并且FVa-Y1961C中APC敏感性的降低导致APC催化失活的显着抑制,在Arg506处延迟裂解,在Arg306处几乎没有裂解,有或没有蛋白质(P)S。FV-Y1961C在由FVIII中的Arg336裂解促进的APC催化的FVIIIa失活中的APC辅因子活性受损。在涉及APC/PS催化的失活和凝血酶原酶活性的反应中,FVa-Y1961C与磷脂膜的结合亲和力降低。此外,血浆中添加FVa-Y1961C未能抑制组织因子(TF)诱导的促凝血功能。这些特征类似于FV-W1920R(FVNara)和FV-A2086D(FVBesançon)。
    结论:;我们鉴定了复合杂合。C1结构域中的FV-Y1961C突变代表新的FV突变(FVKanazawa),不仅由于FVa易感性和FV辅因子对APC功能的活性受损而导致APCR,但TF诱导的促凝血功能抑制受损。这些与FV-Y1961C中FV相关的抗凝功能缺陷导致了血栓前状态。
    BACKGROUND: ; Factor (F)V is pivotal in both procoagulant and anticoagulant mechanisms. The present report describes a novel F5 mutation in a FV-deficient patient (FV:C 6 IU/dL, FV:Ag 32 IU/dL), complicated with recurrent deep vein thrombosis. The patient demonstrated activated protein C resistance (APCR) with compound heterozygous mutations consisting of FV-Y1961C (FVKanazawa) and FV-1982_1983del. AIM;: To clarify thrombotic mechanisms associated with this FV abnormality.
    RESULTS: Levels of FV-1982_1983del were below the detection sensitivity in our expression experiments using HEK293T cells, and analyses were targeted, therefore on the FV-Y1961C mutation. APTT-based clotting assays demonstrated that FV-Y1961C exhibited APCR, and that the reduced APC susceptibility in FVa-Y1961C resulted in a marked depression of APC-catalyzed inactivation with delayed cleavage at Arg506 and little cleavage at Arg306 with or without protein (P)S. The APC cofactor activity of FV-Y1961C in APC-catalyzed FVIIIa inactivation promoted by Arg336 cleavage in FVIII was impaired. The binding affinity of FVa-Y1961C to phospholipid membranes was reduced in reactions involving APC/PS-catalyzed inactivation and in prothrombinase activity. Furthermore, the addition of FVa-Y1961C to plasma failed to inhibit tissue factor (TF)-induced procoagulant function. These characteristics were similar to those of FV-W1920R (FVNara) and FV-A2086D (FVBesançon).
    CONCLUSIONS: ; We identified a compound heterozygous. FV-Y1961C mutation in the C1 domain representing a novel FV mutation (FVKanazawa) resulting in not only APCR due to impaired FVa susceptibility and FV cofactor activity for APC function, but impaired inhibition of TF-induced procoagulant function. These defects in anticoagulant function associated with FV in FV-Y1961C contributed to a prothrombotic state.
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  • 文章类型: Journal Article
    为了满足消费者的高需求,在过去的几年里,黄油的产量有所增加。因此,酪乳(BM)共同生产的卷需要新的增值方式,例如在奶酪制造中。然而,奶酪牛奶中的BM使用会对奶酪制作过程产生负面影响(例如,改变的凝固特性)和产品的最终质量(例如,高水分含量)。通过超滤(UF)浓缩BM可能会通过增加蛋白质含量同时保持乳盐平衡来促进其在奶酪生产中的使用。同时,对UFBM奶酪的消化知之甚少。因此,本研究旨在表征UFBM对奶酪生产的影响,其结构,及其在体外消化过程中的行为。将2倍UF浓缩的BM用于干酪制造(脱脂乳[SM]-对照)。组成,纹理,首先对奶酪进行了微观结构分析。第二步,将奶酪喂入胃和小肠的体外TNO胃肠道消化模型(TIM-1),并研究了蛋白质和磷脂(PL)的生物可及性。结果表明,UFBM干酪与SM干酪的成分明显不同,硬度(p<0.05)和微观结构。然而,在TIM-1中,UFBM和SM奶酪显示出类似的消化行为,占蛋白质和PL摄入量的百分比。尽管UFBM奶酪的回肠外排中相对较多的非消化和非吸收PL,与SM奶酪相比,最初较高的PL浓度有助于提高营养价值。据我们所知,这项研究是第一个比较UFBM和SM奶酪中蛋白质和PL的生物可及性的研究。
    To meet the high consumer demand, butter production has increased over the last few years. As a result, the buttermilk (BM) co-produced volumes require new ways of adding value, such as in cheese manufacturing. However, BM use in cheese milk negatively influences the cheesemaking process (e.g., altered coagulation properties) and the product\'s final quality (e.g., high moisture content). The concentration of BM by ultrafiltration (UF) could potentially facilitate its use in cheese manufacturing through an increased protein content while maintaining the milk salt balance. Simultaneously, little is known about the digestion of UF BM cheese. Therefore, this study aimed to characterize the impact of UF BM on cheese manufacture, its structure, and its behavior during in vitro digestion. A 2-fold UF concentrated BM was used for cheese manufacture (skim milk [SM] - control). Compositional, textural, and microstructural analyses of cheeses were first conducted. In a second step, the cheeses were fed into an in vitro TNO gastrointestinal digestion model (TIM-1) of the stomach and small intestine and protein and phospholipid (PL) bioaccessibility was studied. The results showed that UF BM cheese significantly differed from SM cheese regarding its composition, hardness (p < 0.05) and microstructure. However, in TIM-1, UF BM and SM cheeses showed similar digestion behavior as a percentage of protein and PL intake. Despite relatively more non-digested and non-absorbed PL in the ileum efflux of UF BM cheese, the initially higher PL concentration contributes to an enhanced nutritional value compared to SM cheese. To our knowledge, this study is the first to compare the bioaccessibility of proteins and PL from UF BM and SM cheeses.
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  • 文章类型: Journal Article
    我们重点介绍邱等人的最新作品。关于具有两个多不饱和脂肪酰尾巴的稀有磷脂(PL-PUFA2s)诱导铁死亡的核心机制,已在Cell上发表。长期以来,人们一直认为含有一个PUFA尾部的PL(PL-PUFA1s)在铁凋亡过程中作为磷脂过氧化的底物,由于它们对体内氧化和流行的敏感性。然而,作者指出,PL-PUFA2s,而不是PL-PUFA1s,代表参与促铁蛋白过程的关键脂质类别。外源性磷脂酰胆碱-PUFA2s在线粒体中积累,并在电子传递链中与复合物I结合,从而可能导致线粒体活性氧水平的升高。然后,这些线粒体过氧化物促使内质网内的过氧化物大量积累,最终导致铁中毒。这些发现揭示了膳食PL-PUFA2诱导铁凋亡的潜在分子机制,并为评估细胞铁死亡敏感性和癌症治疗提供了新的见解。本文将对论文进行更全面的阐述,并促进读者对潜在机制的理解。
    We highlight the latest work of Qiu et al. on the core mechanism of ferroptosis induced by rare phospholipids with two polyunsaturated fatty acyl tails (PL-PUFA2s), which has been published in Cell. It has long been acknowledged that PLs containing one PUFA tail (PL-PUFA1s) serve as substrates for phospholipid peroxidation during the process of ferroptosis, owing to their susceptibility to oxidation and prevalence in vivo. However, the authors note that PL-PUFA2s, rather than PL-PUFA1s, represent critical lipid classes involved in the pro-ferroptosis process. Exogenous phosphatidylcholine-PUFA2s accumulate in mitochondria and combine with Complex I within the electron transport chain, thereby potentially resulting in an elevation of mitochondrial reactive oxygen species levels. Then, these mitochondrial peroxides prompt the substantial accumulation of peroxides within the endoplasmic reticulum, ultimately culminating in ferroptosis. These findings shed light on the potential molecular mechanisms underlying the induction of ferroptosis by dietary PL-PUFA2s and offer novel insights for both the evaluation of cellular iron death sensitivity and the treatment of cancer. This article will provide a more comprehensive elucidation of the paper and facilitate an enhanced understanding of the underlying mechanisms for readers.
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  • 文章类型: Journal Article
    心磷脂(CL)是一种线粒体特异性磷脂,与膜形成蛋白形成异型相互作用,并调节线粒体的动态重塑和功能。然而,CL影响线粒体形态的确切机制尚不清楚。在这项研究中,采用分子动力学(MD)模拟,我们观察到CL位于线粒体融合蛋白视神经萎缩1(OPA1)的膜结合位点附近。为了通过实验验证这些发现,我们开发了溴标记的CL探针以增强冷冻EM对比度并表征与CL溴化脂质双层结合的OPA1组装体的结构。我们的图像提供了CL与OPA1的桨域(PD)内两个保守基序之间相互作用的直接证据,这些基序控制膜成形机制。我们进一步观察到,随着单氢心磷脂(MLCL)浓度的增加,脂质组合物中OPA1的膜重塑活性降低。建议用MLCL积累部分替代CL,如在他法津磷脂转酰酶的Barth综合征相关突变中观察到的,损害了蛋白质-膜相互作用的稳定性。我们的分析提供了有关生物膜如何调节线粒体稳态的机制的见解。
    这项研究揭示了CL如何调节OPA1的活性以及MLCL如何影响其控制线粒体功能的能力。
    Cardiolipin (CL) is a mitochondria-specific phospholipid that forms heterotypic interactions with membrane-shaping proteins and regulates the dynamic remodeling and function of mitochondria. However, the precise mechanisms through which CL influences mitochondrial morphology are not well understood. In this study, employing molecular dynamics (MD) simulations, we observed CL localize near the membrane-binding sites of the mitochondrial fusion protein Optic Atrophy 1 (OPA1). To validate these findings experimentally, we developed a bromine-labeled CL probe to enhance cryoEM contrast and characterize the structure of OPA1 assemblies bound to the CL-brominated lipid bilayers. Our images provide direct evidence of interactions between CL and two conserved motifs within the paddle domain (PD) of OPA1, which control membrane-shaping mechanisms. We further observed a decrease in membrane remodeling activity for OPA1 in lipid compositions with increasing concentrations of monolyso-cardiolipin (MLCL). Suggesting that the partial replacement of CL by MLCL accumulation, as observed in Barth syndrome-associated mutations of the tafazzin phospholipid transacylase, compromises the stability of protein-membrane interactions. Our analyses provide insights into how biological membranes regulate the mechanisms governing mitochondrial homeostasis.
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  • 文章类型: Journal Article
    Ethosome为常规药物递送系统所面临的挑战提供了独特的解决方案。与传统的脂质体和其他纳米载体相比,乙醇体表现出独特的改善药物吸收的能力,克服了经皮给药系统的主要限制。它们柔软灵活的纳米囊泡结构有助于更快的渗透,导致明显更高的透皮通量。这项科学研究有效地穿越了作为创新药物输送系统的醇体不断变化的格局。通过进行彻底的比较分析,我们发现了将它们与其他纳米载体区分开来的独特特征,提供对其独特优势的见解。该研究还包括对对绩效有复杂影响的变量的详细分析,阐明运输机制和解决先进的方面是精制药物输送策略的关键。这份全面的概述强调了乙醇体是医学的未来,为各种疾病的安全有效治疗提供了一个充满希望的未来,影响无数人的生活。
    Ethosome offers a unique solution to the challenges faced by conventional drug delivery systems. In comparison to traditional liposomes and other nanocarriers, ethosomes exhibit a unique ability to improve drug absorption, overcoming a major limitation in the Transdermal Drug Delivery System. Their soft and flexible nano-vesicular structure facilitates faster permeation, resulting in significantly higher transdermal flux. This scientific investigation effectively traverses the changing landscape of ethosomes as an innovative drug delivery system. By conducting a thorough comparative analysis, we uncover the distinct characteristics that set them apart from other nanocarriers, offering insights into their distinct advantages. The study also includes a detailed analysis of the variables that have a complex impact on performance, elucidating transport mechanisms and addressing advanced facets pivotal for refined drug delivery strategies. This comprehensive overview highlights ethosomes as a future of medicine, offering a promising future for the safe and effective treatment of diverse diseases, impacting numerous lives.
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  • 文章类型: Journal Article
    牛奶磷脂有多种健康益处,但是乳制品中详细磷脂谱的缺乏给乳制品磷脂的摄入量计算和功能评估带来了障碍。在目前的研究中,在207个牛奶中鉴定并定量了306个磷脂分子种类,酸奶和奶油产品使用HILIC-ESI-Q-TOFMS和HILIC-ESI-QQQMS。五种哺乳动物乳的磷脂谱表明骆驼乳含有最丰富的磷脂酰乙醇胺,磷脂酰丝氨酸和鞘磷脂;牛,牦牛和山羊奶有相似的磷脂体,而水牛奶中含有丰富的磷脂酰肌醇。在超高温(UHT)灭菌牛奶中发现了比巴氏杀菌牛奶更少的疟原虫,但更多的溶血甘油磷脂,在奶油和脱脂/半脱脂牛奶中观察到的溶血甘油磷脂/总磷脂比例高于全脂牛奶,表明UHT和撇脂过程改善了甘油磷脂的降解和磷脂营养损失。同时,更多的二酰基甘油磷脂和更少的降解产物使酸奶成为比全脂牛奶更好的磷脂资源。
    Milk phospholipids have multiple health benefits, but the deficiency of detailed phospholipid profiles in dairy products brings obstacles to intake calculation and function evaluation of dairy phospholipids. In present study, 306 phospholipid molecular species were identified and quantified among 207 milk, yogurt and cream products using a HILIC-ESI-Q-TOF MS and a HILIC-ESI-QQQ MS. The phospholipid profiles of five mammals\' milk show that camel milk contains the most abundant phosphatidylethanolamine, phosphatidylserine and sphingomyelin; cow, yak and goat milk have similar phospholipidomes, while buffalo milk contains abundant phosphatidylinositol. Fewer plasmalogens but more lyso-glycerolphospholipids were found in ultra-high-temperature (UHT) sterilized milk than in pasteurized milk, and higher proportions of lyso-glycerolphospholipid/total phospholipid were observed in both cream and skimmed/semi-skimmed milk than whole milk, indicating that UHT and skimming processes improve glycerolphospholipid degradation and phospholipid nutrition loss. Meanwhile, more diacyl-glycerolphospholipids and less of their degradation products make yogurt a better phospholipid resource than whole milk.
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  • 文章类型: Journal Article
    背景:根据肝活检的组织学发现,非酒精性脂肪性肝病分为单纯性脂肪变性(SS)和非酒精性脂肪性肝炎(NASH)。磷脂酰胆碱(PC),磷脂的主要成分在血清脂蛋白,容易被氧化成磷脂酰胆碱过氧化氢(PC-OOH)。尽管NASH患者的低密度脂蛋白(LDL)中的脂质成分可能异常,目前还不清楚。这里,为了更好地了解NASH和SS的LDL中的脂质特征,我们比较了LDL颗粒中PC和PC-OOH种类的组成(LDL-PC,LDL-PCOOH)来自这些患者,然后阐明这些脂质与NASH严重程度之间的关联.
    方法:NASH患者的血清样本(女性,n=9)和SS(女性,n=4;男性,n=2)用于分离LDL。从分离的LDL中提取总脂质,使用液相色谱-质谱/质谱法测量PC和PC-OOH的种类。
    结果:NASH中LDL-PC和LDL-PCOOH的总和明显高于SS。几个LDL-PC(PC32:0,32:1,32:2,34:3,36:2,具有饱和脂肪酰基链的PC总和和具有多不饱和脂肪酰基链的LDL-PC总和)和几个LDL-PCOOH(34:2,36:2,36:3和总计)随着纤维化评分的增加而显着增加。特别是,一系列LDL-PCOOH更能反映纤维化评分的严重程度.
    结论:LDL-PC和LDL-PCOOH物种与NASH的纤维化评分密切相关,这表明异常LDL参与肝纤维化的发展。
    BACKGROUND: Non-alcoholic fatty liver disease is classified into simple steatosis (SS) and non-alcoholic steatohepatitis (NASH) according to histological findings from liver biopsies. Phosphatidylcholine (PC), the main component of phospholipids in serum lipoproteins, is easily oxidized to phosphatidylcholine hydroperoxide (PC-OOH). Although a lipid composition in the low-density lipoproteins (LDL) from patients with NASH could be abnormal, it remains unclear. Here, to better understand the characteristics of lipids in the LDL from NASH and SS, we compared the composition of PC and PC-OOH species in LDL particles (LDL-PC, LDL-PCOOH) from these patients, then clarified the association between these lipids and NASH severity.
    METHODS: The serum samples from patients with NASH (female, n = 9) and SS (female, n = 4; male, n = 2) were used for isolation of LDL. Total lipids were extracted from isolated LDL, and the species of PC and PC-OOH were measured using liquid chromatography-mass spectrometry/mass spectrometry.
    RESULTS: The sum of LDL-PC and the sum of LDL-PCOOH were significantly higher in NASH than in SS. Several LDL-PC (PC 32:0, 32:1, 32:2, 34:3, 36:2, sum of PC with saturated fatty acyl chains and sum of LDL-PC with polyunsaturated fatty acyl chains) and several LDL-PCOOH (34:2, 36:2, 36:3 and total) were increased significantly with increasing fibrosis score. In particular, a series of LDL-PCOOH were more reflective of the severity of fibrosis score.
    CONCLUSIONS: LDL-PC and LDL-PCOOH species were strongly correlated with the fibrosis score in NASH, which suggests that abnormal LDL is involved in the development of liver fibrosis.
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  • 文章类型: Journal Article
    由于磷脂对大小有重要影响,脂质体的表面电势和硬度决定了它们吸入后的体内命运,本研究系统评价了磷脂对脂质体肺部给药的影响。在这项研究中,由中性饱和/不饱和磷脂组成的脂质体,构建了阴离子和阳离子磷脂,以研究表面电势和脂肪酸链的饱和度如何在体外和体内决定其粘液和上皮渗透性。我们的研究结果清楚地表明,由饱和中性和阴离子磷脂组成的脂质体具有很高的稳定性和渗透性,与由不饱和磷脂和阳离子磷脂组成的脂质体相比。此外,进行了荧光标记脂质体的体内成像和脂质体中包封的丹酚酸B(SAB)的生物分布,以评估磷脂对吸入脂质体的肺暴露和滞留的影响.最后,吸入SAB脂质体通过抑制炎症和调节凝血-纤溶系统,在博来霉素诱导的特发性肺纤维化小鼠模型中显示出增强的治疗效果.这些发现将有益于开发用于治疗呼吸道疾病的可吸入的基于脂质的纳米药物递送系统,其中吸入是优选的施用途径。
    Since phospholipids have an important effect on the size, surface potential and hardness of liposomes that decide their in vivo fate after inhalation, this research has systematically evaluated the effect of phospholipids on pulmonary drug delivery by liposomes. In this study, liposomes composed of neutral saturated/unsaturated phospholipids, anionic and cationic phospholipids were constructed to investigate how surface potential and the degree of saturation of fatty acid chains determined their mucus and epithelium permeability both in vitro and in vivo. Our results clearly indicated that liposomes composed of saturated neutral and anionic phospholipids possessed high stability and permeability, compared to that of liposomes composed of unsaturated phospholipids and cationic phospholipids. Furthermore, both in vivo imaging of fluorescence-labeled liposomes and biodistribution of salvianolic acid B (SAB) that encapsulated in liposomes were performed to estimate the effect of phospholipids on the lung exposure and retention of inhaled liposomes. Finally, inhaled SAB-loaded liposomes exhibited enhanced therapeutic effects in a bleomycin-induced idiopathic pulmonary fibrosis mice model via inhibition of inflammation and regulation on coagulation-fibrinolytic system. Such findings will be beneficial to the development of inhalable lipid-based nanodrug delivery systems for the treatment of respiratory diseases where inhalation is the preferred route of administration.
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