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  • 文章类型: Journal Article
    背景:TARDNA结合蛋白43(TDP-43)病理包涵体是数十种神经退行性病变的显着特征,包括边缘占优势的年龄相关的TDP-43脑病神经病理变化(LATE-NC)。先前的研究确定了血管相关的TDP-43阳性微病变,被称为“林的尸体,位于某些患有LATE-NC的人的脑毛细血管上或附近。本研究旨在探讨LATE-NC中Lin体和胶质细胞的积累与铁蛋白的潜在共定位之间的关系。一种与铁储存有关的蛋白质。使用多重免疫组织化学和数字病理学工具,我们进行了病理学分析,以研究Lin体与神经胶质标志物之间的关系(星形胶质细胞的GFAP,IBA1表示小胶质细胞)和铁蛋白。对从病理证实为阿尔茨海默病神经病理学改变(ADNC)和LATE-NC的个体收集的死后脑组织进行分析。
    结果:如前所述,Lin体与GFAP阳性星形胶质细胞过程之间存在显著关联.此外,我们还观察到Lin身体经常与铁蛋白共同定位,提示血管完整性受损的潜在联系。随后的分析表明,与没有林体的血管相比,林体阳性血管附近的星形细胞增多,特别是在ADNC的情况下。这些结果表明,林体的积累可能会引起神经胶质反应增加,特别是在星形胶质细胞中,可能与血管完整性受损有关。
    结论:Lin体与局部反应性神经胶质反应有关。Lin体与铁蛋白的强烈关联表明血管完整性的丧失可能是pTDP-43病理的原因或结果。受影响血管周围的反应性神经胶质可能进一步损害血管功能。
    BACKGROUND: TAR DNA-Binding Protein 43 (TDP-43) pathological inclusions are a distinctive feature in dozens of neurodegenerative pathologies, including limbic-predominant age-related TDP-43 encephalopathy neuropathologic change (LATE-NC). Prior investigations identified vascular-associated TDP-43-positive micro-lesions, known as \"Lin bodies,\" located on or near the brain capillaries of some individuals with LATE-NC. This study aimed to investigate the relationship between the accumulation of Lin bodies and glial cells in LATE-NC and the potential co-localization with ferritin, a protein associated with iron storage. Using multiplexed immunohistochemistry and digital pathology tools, we conducted pathological analyses to investigate the relationship between Lin bodies and glial markers (GFAP for astrocytes, IBA1 for microglia) and ferritin. Analyses were conducted on post-mortem brain tissues collected from individuals with pathologically confirmed Alzheimer\'s disease neuropathological changes (ADNC) and LATE-NC.
    RESULTS: As shown previously, there was a robust association between Lin bodies and GFAP-positive astrocyte processes. Moreover, we also observed Lin bodies frequently co-localizing with ferritin, suggesting a potential link to compromised vascular integrity. Subsequent analyses demonstrated increased astrocytosis near Lin body-positive vessels compared to those without Lin bodies, particularly in ADNC cases. These results suggest that the accumulation of Lin bodies may elicit an increased glial response, particularly among astrocytes, possibly related to impaired vascular integrity.
    CONCLUSIONS: Lin bodies are associated with a local reactive glial response. The strong association of Lin bodies with ferritin suggests that the loss of vascular integrity may be either a cause or a consequence of the pTDP-43 pathology. The reactive glia surrounding the affected vessels could further compromise vascular function.
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  • 文章类型: Journal Article
    Ferroptosis,一种新兴的程序性细胞死亡,由铁依赖性和过量的ROS介导的脂质过氧化引发,最终导致质膜破裂和细胞死亡。许多典型的信号传导途径和生物过程参与铁死亡。此外,由于ROS的高负荷和独特的代谢特征,癌细胞更容易发生铁死亡,包括铁的要求。最近的研究表明,铁性凋亡在肿瘤的进展中起着至关重要的作用,尤其是HCC。具体来说,铁凋亡的诱导不仅可以抑制肝癌细胞的生长,从而逆转肿瘤发生,而且还提高了免疫疗法的疗效并增强了抗肿瘤免疫反应。因此,触发铁性凋亡已成为癌症治疗的一种新的治疗策略。在这次审查中,我们根据其在HCC中的潜在机制和作用总结了铁死亡的特征,并提供了可能的治疗应用。
    Ferroptosis, an emerging type of programmed cell death, is initiated by iron-dependent and excessive ROS-mediated lipid peroxidation, which eventually leads to plasma membrane rupture and cell death. Many canonical signalling pathways and biological processes are involved in ferroptosis. Furthermore, cancer cells are more susceptible to ferroptosis due to the high load of ROS and unique metabolic characteristics, including iron requirements. Recent investigations have revealed that ferroptosis plays a crucial role in the progression of tumours, especially HCC. Specifically, the induction of ferroptosis can not only inhibit the growth of hepatoma cells, thereby reversing tumorigenesis, but also improves the efficacy of immunotherapy and enhances the antitumour immune response. Therefore, triggering ferroptosis has become a new therapeutic strategy for cancer therapy. In this review, we summarize the characteristics of ferroptosis based on its underlying mechanism and role in HCC and provide possible therapeutic applications.
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  • 文章类型: Journal Article
    线粒体铁蛋白(FtMt)是一种新型的铁蛋白,可螯合铁并对氧化应激起保护作用。FtMt与H-铁蛋白具有高度同源性,但仅在大脑中表达,心,和睾丸。在中脑,在黑质中观察到FtMt表达。FtMt在帕金森病等神经退行性疾病的病理学中起神经保护作用。过量的铁诱导氧化应激,导致细胞死亡。在这里,我们研究了蛛网膜下腔出血(SAH)患者大脑中的FtMt免疫反应性。在对照组和SAH病例中,酪氨酸羟化酶(TH)和FtMt的双重免疫荧光标记在黑质致密部(SNc)中显示出高度的共定位。然而,在SAH病例中,在一些TH阴性神经元中观察到FtMt免疫反应性。神经胶质细胞标记和FtMt的双重免疫荧光标记显示没有明显的共定位。对照组和SAH组之间FtMt阳性但TH阴性神经元的数量和比例显着不同。SAH病例中的普鲁士蓝染色显示在较宽的表面范围和黑质上呈阳性铁染色。因此,FtMt可能与蛛网膜下腔出血后黑质中的铁动力学有关。
    Mitochondrial ferritin (FtMt) is a novel ferritin that sequesters iron and plays a protective role against oxidative stress. FtMt shares a high homology with H-ferritin but is expressed only in the brain, heart, and testis. In the midbrain, FtMt expression is observed in the substantia nigra. FtMt plays a neuroprotective role in the pathology of neurodegenerative diseases such as Parkinson\'s disease, where excessive iron induces oxidative stress, causing cell death. Herein, we investigated FtMt immunoreactivity in the brains of patients with subarachnoid hemorrhage (SAH). Double immunofluorescence labeling of tyrosine hydroxylase (TH) and FtMt showed high colocalization in the substantia nigra pars compacta (SNc) in control and SAH cases. However, in SAH cases, FtMt immunoreactivity was observed in some TH-negative neurons. Double immunofluorescence labeling of glial cell markers and FtMt showed no apparent colocalization. The number and ratio of FtMt-positive but TH-negative neurons significantly differed between the control and SAH groups. Prussian blue staining in SAH cases showed positive iron staining over a wide surface range and the substantia nigra. Thus, FtMt may be related to iron dynamics in the substantia nigra following subarachnoid hemorrhage.
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  • 文章类型: Journal Article
    我们的研究旨在验证在诊断为非贫血至轻度贫血缺铁和疲劳的成年受试者中,与不同补铁相比,血红蛋白胶囊的安全性和有效性。招募了302名被诊断为非贫血至轻度贫血缺铁和疲劳的参与者。A组(n=147)接受血红蛋白,B组(n=146)接受标准护理[HaemUpGems胶囊(富马酸亚铁)或Fericip片剂(抗坏血酸亚铁)]。293名受试者在第30、60和90天完成随访研究。血红蛋白治疗在90天内将血红蛋白水平从平均12.43g/dl显着增加到13.24g/dl。与标准护理的256.67%相比,铁蛋白水平显著提高了442.87%。疲劳量表得分降低47.51%,所有提出的健康投诉都得到了完全解决。两组观察到的胃肠道症状相似。两组均表现出中等的治疗依从性。疼痛和一般健康领域的生活质量得到改善,表现出良好的耐受性。不良事件与研究产品无关。血红蛋白作为一个有效的治疗替代改善血红蛋白,铁蛋白,与标准护理相比,低剂量减少疲劳。然而,低剂量的长期影响需要在不同的目标人群中进一步研究.
    Our study aims to validate safety and efficacy of Feroglobin capsule compared with different iron supplementations in adult subjects diagnosed with non-anemic to mild anemic iron deficiency and fatigue. Enrolled 302 participants diagnosed with non-anemic to mild anemic iron deficiency and fatigue. Group A (n = 147) received Feroglobin, Group B (n = 146) received standard of care [Haem Up Gems capsules (Ferrous fumarate) or Fericip tablets (Ferrous ascorbate)]. 293 subjects completed the study with follow-up visits on days 30, 60, and 90. Feroglobin treatment significantly increased hemoglobin levels from mean 12.43 g/dl to 13.24 g/dl in 90 days. Ferritin levels improved significantly by 442.87% compared to the standard care\'s 256.67%. Fatigue scale scores reduced by 47.51%, and all presenting health complaints resolved completely. Gastrointestinal symptoms observed were similar in both the groups. Both groups exhibited moderate treatment adherence. Quality of life improved in pain and general health domains, exhibiting a good tolerability. Adverse events were unrelated to the investigational products. Feroglobin serves as an efficacious therapeutic alternative for improving hemoglobin, ferritin, and reducing fatigue with low doses compared to standard of care. However, longer-term effects of low-dose require further investigations in different target groups.
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  • 文章类型: Journal Article
    背景:本研究的目的是探索不同血清铁状态之间的因果关系(铁蛋白,转铁蛋白,转铁蛋白饱和度,和血清铁)以及雌激素受体(ER)阳性或ER阴性乳腺癌的发生。
    方法:血清铁状态暴露的汇总数据来自IEUOpenGWAS项目,英国生物银行,和其他数据库。同时,ER+和ER-乳腺癌的汇总数据来自乳腺癌协会联盟(BCAC).通过检查铁状态和乳腺癌之间的因果关系,我们部署了五种不同的孟德尔随机化(MR)算法,即MR-Egger,逆方差加权(IVW),加权中位数,简单模式,MR-PRESSO为了评估异质性和水平多效性,应用了Cochran的Q和MR-Egger算法,分别。
    结果:铁蛋白水平升高与ER阴性乳腺癌风险增加相关(OR(IVW)=1.042,95%CI(1.005,1.081),p=0.025;OR(加权中位数)=1.050,95%CI(1.001,1.102),p=0.046;OR(MR-PRESSO)=1.042,95%CI(1.005,1.081),p=0.039)。相反,血清铁水平的升高与ER阴性乳腺癌的风险降低有关(OR(IVW)=0.791,95%CI(0.649,0.962),p=0.019;OR(MR-PRESSO)=0.791,95%CI(0.649,0.962),p=0.028)。然而,没有证据表明转铁蛋白之间存在因果关系,转铁蛋白饱和度,和ER阴性乳腺癌。对于ER阳性乳腺癌,四种不同的铁状态均无因果关系.
    结论:铁蛋白与ER阴性乳腺癌呈正相关,而血清铁与ER阴性乳腺癌呈负相关。然而,四种铁状态与ER阳性乳腺癌之间没有因果关系.
    BACKGROUND: The aim of this study was to explore the causal relationship between different serum iron statuses (ferritin, transferrin, transferrin saturation, and serum iron) and the occurrence of estrogen receptor (ER)-positive or ER-negative breast cancer.
    METHODS: The summary data on serum iron status exposure were gathered from the IEU OpenGWAS Project, the UK Biobank, and other databases. Concurrently, the summary data for ER+ and ER- breast cancer are sourced from the Breast Cancer Association Consortium (BCAC). By examining the causal link between iron status and breast cancer, we deployed five distinct Mendelian randomization (MR) algorithms, namely MR-Egger, inverse variance weighted (IVW), weighted median, simple mode, and MR-PRESSO. To assess heterogeneity and horizontal pleiotropy, Cochran\'s Q and MR-Egger algorithms were applied, respectively.
    RESULTS: Elevated ferritin levels are associated with an increased risk of ER-negative breast cancer (OR(IVW) = 1.042, 95% CI (1.005, 1.081), p = 0.025; OR (weighted median) = 1.050, 95% CI (1.001, 1.102), p = 0.046; and OR (MR-PRESSO) = 1.042, 95% CI (1.005, 1.081), p = 0.039). Conversely, an increase in the serum iron level is linked to a reduced risk of ER-negative breast cancer (OR (IVW) = 0.791, 95% CI (0.649, 0.962), p = 0.019; and OR (MR-PRESSO) = 0.791, 95% CI (0.649, 0.962), p = 0.028). However, there is no evidence of a causal relationship between transferrin, transferrin saturation, and ER-negative breast cancer. For ER-positive breast cancer, none of the four different iron statuses demonstrated a causal relationship.
    CONCLUSIONS: Ferritin is positively correlated with ER-negative breast cancer, while serum iron is negatively associated with ER-negative breast cancer. However, there is no causal relationship between the four iron statuses and ER-positive breast cancer.
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  • DOI:
    文章类型: Journal Article
    目标-绝经后妇女(PMW)经历了缺乏或不足的女性性激素的生理阶段,导致一些后果,包括血液学缺陷。本研究旨在研究使用简单的实验室工具检测绝经后妇女的贫血。在对2014-2022年期间收集的患者数据的回顾性分析中。从PMW记录中检索的数据收集并分析了4年。与正常范围相比,PMW的数据显示血红蛋白水平降低,细胞体积,平均红细胞体积,和平均红细胞血红蛋白。PMW还显示红细胞分布宽度和血清铁水平升高。与正常范围相比,红细胞计数没有变化,平均红细胞血红蛋白浓度,不饱和或总铁结合能力,转铁蛋白饱和度,血清铁蛋白,白细胞计数,和血小板。进行深入的调查,我们根据参与者的年龄将他们分为三组:45-55岁,56-65岁,66-80岁。年龄越大,更多的参数被改变。该研究强调了绝经后激素改变对血液学参数的潜在影响,并且常规实验室工具可用于评估血液参数的这种改变。
    Objectives - postmenopausal women (PMW) undergo a physiological phase of lack or insufficient female sex hormones resulting in some consequences including hematological deficits. The present study aimed to investigate the detection of anemia in postmenopausal women using easy laboratory tools. In this retrospective analysis of patient data collected during the period between 2014-2022. Data retrieved from PMW records were collected over 4 years and analyzed. In comparison to normal ranges, data of PMW has shown reduced levels of hemoglobin, packed cell volume, mean corpuscular volume, and mean corpuscular hemoglobin. PMW has also shown elevated levels of red cell distribution width and levels of serum iron. Compared to normal ranges, no changes have been seen regarding red blood cell count, Mean corpuscular hemoglobin concentration, unsaturated or total iron binding capacity, transferrin saturation, serum ferritin, white blood cells count, and platelets. To provide in-depth investigation, we divide our participants into three groups according to their ages: 45-55 years, 56-65 years, and 66-80 years. The older the age, the more parameters are altered. The study highlighted the potential impact of postmenopausal hormone alteration on hematological parameters and the routine laboratory tools could be used to assess such alteration in blood parameters.
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  • 文章类型: Journal Article
    目的:研究婴儿配方奶粉中降低的铁含量和添加的牛乳铁蛋白如何影响常规免疫后的抗体反应。
    方法:在这项随机对照试验中,收到180名瑞典配方奶粉喂养的婴儿,从6周到6个月大,含(n=72)或不含(n=72)牛乳铁蛋白的2mg/L铁配方,或具有8mg/L铁且无乳铁蛋白的对照配方(n=36)。另外72名婴儿被招募作为母乳喂养的参考。血清免疫球蛋白G(IgG)水平对b型流感嗜血杆菌(Hib),四时评估白喉和破伤风,6个月和12个月大。
    结果:性别分布平等,包括180+72名足月儿,平均年龄为7.0±0.7周。12个月时,与对照配方奶粉婴儿(0.67μg/mL[0.42-1.07])相比,低铁配方奶粉喂养的婴儿显示出显著更高的几何平均HibIgG(1.40μg/mL[1.07-1.83]).对于所有三种疫苗,母乳喂养的婴儿在6个月和12个月时IgG水平显著降低.
    结论:除了低铁配方喂养的婴儿在12个月时HibIgG水平较高,干预措施未影响疫苗IgG应答.出乎意料的是,母乳喂养婴儿的疫苗IgG水平显著低于配方喂养婴儿.
    OBJECTIVE: To examine how reduced iron content and added bovine lactoferrin in infant formula affect the antibody response following routine immunisation.
    METHODS: In this randomised controlled trial, 180 Swedish formula-fed infants received, from 6 weeks to 6 months of age, a 2 mg/L iron formula with (n = 72) or without (n = 72) bovine lactoferrin, or a control formula with 8 mg/L iron and no lactoferrin (n = 36). Another 72 infants were recruited as a breastfed reference. Serum immunoglobulin G (IgG) levels against Haemophilus influenzae type b (Hib), diphtheria and tetanus were assessed at four, six and 12 months of age.
    RESULTS: With an equal gender distribution, 180 + 72 term infants were included with a mean age of 7.0 ± 0.7 weeks. At 12 months, infants fed low iron formula showed a significantly higher geometric mean Hib IgG (1.40 μg/mL [1.07-1.83]) compared to the control formula infants (0.67 μg/mL [0.42-1.07]). For all three vaccines, breastfed infants had significantly lower IgG levels at six and 12 months of age.
    CONCLUSIONS: Except for higher Hib IgG levels at 12 months in infants fed low iron formula, the interventions did not affect vaccine IgG response. Unexpectedly, breastfed infants had significantly lower vaccine IgG levels compared to formula-fed infants.
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  • 文章类型: Journal Article
    背景:以前的研究,包括孟德尔随机化(MR),已经证明2型糖尿病(T2D)和血糖特征与代谢功能障碍相关的脂肪变性肝病(MASLD)的风险增加有关。然而,很少有研究探索潜在的途径,如铁稳态的作用。
    方法:我们使用两步MR方法来调查T2D的遗传易感性的关联,血糖性状,铁生物标志物,和肝脏疾病。我们分析了T2D的各种全基因组关联研究的汇总统计数据(n=933,970),血糖性状(n≤209,605),铁生物标志物(n≤246,139),MASLD(n≤972,707),和相关的生物标志物(丙氨酸氨基转移酶(ALT)和质子密度脂肪分数(PDFF))。我们的主要分析是基于方差逆加权,其次是一些敏感性分析。我们还进行了中介分析,并探讨了肝铁在事后分析中的作用。
    结果:T2D的遗传倾向和空腹胰岛素(FI)升高可能会增加肝脏脂肪变性的风险(对T2D的倾向:患病率每增加一倍1.14,95%CI:1.10,1.19;ORFI:3.31/logpmol/l,95%CI:1.92,5.72)和相关生物标志物。T2D的责任也可能增加发展为肝硬化的风险。基因升高的铁蛋白,血清铁,和肝脏铁与肝脏脂肪变性的高风险相关(ORferritin:1.25/SD,95%CI1.07,1.46;奥利弗铁:每SD1.15,95%CI:1.05,1.26)和肝硬化(OR血清铁:1.31,95%CI:1.06,1.63;ORliver铁:1.34,95%CI:1.07,1.68)。铁蛋白部分介导FI和肝脏脂肪变性之间的关联(介导的比例:7%,95%CI:2-12%)。
    结论:我们的研究为T2D和胰岛素升高在肝脏脂肪变性和肝硬化风险中的因果作用提供了可靠的证据,并表明铁蛋白可能在这种关联中起中介作用。
    BACKGROUND: Previous studies, including Mendelian randomization (MR), have demonstrated type 2 diabetes (T2D) and glycemic traits are associated with increased risk of metabolic dysfunction-associated steatotic liver disease (MASLD). However, few studies have explored the underlying pathway, such as the role of iron homeostasis.
    METHODS: We used a two-step MR approach to investigate the associations of genetic liability to T2D, glycemic traits, iron biomarkers, and liver diseases. We analyzed summary statistics from various genome-wide association studies of T2D (n = 933,970), glycemic traits (n ≤ 209,605), iron biomarkers (n ≤ 246,139), MASLD (n ≤ 972,707), and related biomarkers (alanine aminotransferase (ALT) and proton density fat fraction (PDFF)). Our primary analysis was based on inverse-variance weighting, followed by several sensitivity analyses. We also conducted mediation analyses and explored the role of liver iron in post hoc analysis.
    RESULTS: Genetic liability to T2D and elevated fasting insulin (FI) likely increased risk of liver steatosis (ORliability to T2D: 1.14 per doubling in the prevalence, 95% CI: 1.10, 1.19; ORFI: 3.31 per log pmol/l, 95% CI: 1.92, 5.72) and related biomarkers. Liability to T2D also likely increased the risk of developing liver cirrhosis. Genetically elevated ferritin, serum iron, and liver iron were associated with higher risk of liver steatosis (ORferritin: 1.25 per SD, 95% CI 1.07, 1.46; ORliver iron: 1.15 per SD, 95% CI: 1.05, 1.26) and liver cirrhosis (ORserum iron: 1.31, 95% CI: 1.06, 1.63; ORliver iron: 1.34, 95% CI: 1.07, 1.68). Ferritin partially mediated the association between FI and liver steatosis (proportion mediated: 7%, 95% CI: 2-12%).
    CONCLUSIONS: Our study provides credible evidence on the causal role of T2D and elevated insulin in liver steatosis and cirrhosis risk and indicates ferritin may play a mediating role in this association.
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  • 文章类型: Journal Article
    固着的植物暴露于不同的环境挑战和随之而来的与之相关的压力。以矿物质为生长和发育的前提,他们协调从土壤到根部的动员。磷(P)和铁(Fe)是大量和微量营养素;P是生物大分子的重要组成部分,除了驱动主要的细胞过程,包括光合作用和呼吸作用,和Fe执行作为重要代谢途径的酶的辅因子的功能。这些矿物质通过改变pH值帮助保持植物活力,营养成分,在根表面释放分泌物,根微生物种群的变化动态,和氧化还原酶活性的调节。尽管如此,它们的低溶解度和在土壤中的相对固定使它们无法被植物利用。此外,植物已经进化出不同的机制来应对这些胁迫,并共同调节矿物质的水平(Fe,P,等。)朝着维持体内平衡的方向发展。本研究旨在研究铁和磷的吸收机制,以及它们的易位,storage,以及在植物中执行不同细胞过程的作用。它还总结了这些矿物质对发芽的影响的毒理学方面,营养吸收,植物与水的关系,和总产量。被认为是可持续农业不可或缺的重要组成部分,单独的部分涵盖了有关Fe和P之间串扰的当前知识,并整合了它们对植物激素水平的影响的完整和平衡的信息。
    Plants being sessile are exposed to different environmental challenges and consequent stresses associated with them. With the prerequisite of minerals for growth and development, they coordinate their mobilization from the soil through their roots. Phosphorus (P) and iron (Fe) are macro- and micronutrient; P serves as an important component of biological macromolecules, besides driving major cellular processes, including photosynthesis and respiration, and Fe performs the function as a cofactor for enzymes of vital metabolic pathways. These minerals help in maintaining plant vigor via alterations in the pH, nutrient content, release of exudates at the root surface, changing dynamics of root microbial population, and modulation of the activity of redox enzymes. Despite this, their low solubility and relative immobilization in soil make them inaccessible for utilization by plants. Moreover, plants have evolved distinct mechanisms to cope with these stresses and coregulate the levels of minerals (Fe, P, etc.) toward the maintenance of homeostasis. The present study aims at examining the uptake mechanisms of Fe and P, and their translocation, storage, and role in executing different cellular processes in plants. It also summarizes the toxicological aspects of these minerals in terms of their effects on germination, nutrient uptake, plant-water relationship, and overall yield. Considered as an important and indispensable component of sustainable agriculture, a separate section covers the current knowledge on the cross-talk between Fe and P and integrates complete and balanced information of their effect on plant hormone levels.
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  • 文章类型: Journal Article
    经过持续42年的长期植入,研究了AISI304不锈钢螺钉与颅骨之间的界面。使用最先进的分析技术分析包含界面区域的样品,包括二次离子质量,傅里叶变换红外,拉曼,和X射线光电子能谱。使用聚焦离子束技术从界面区域切割用于扫描透射电子显微镜的局部样品。以涵盖微米和纳米级分辨率的长度尺度记录了整个界面的化学成分,并且在植入物周围和远端颅骨之间发现了相关差异,表明种植体周围区域通常较年轻的骨组织。此外,能量色散光谱显示出80nm厚的富含氧的钢表面层,表明AISI304材料经历了腐蚀攻击。攻击与金属离子的运输有关,即,亚铁和三价铁,进入邻近植入物的骨层。结果符合释放的铁离子和破骨细胞增殖之间的预期相互作用。相互作用产生自催化过程,其中铁离子刺激破骨细胞活性,而新鲜骨吸收位点的形成通过酸性破骨细胞细胞外区室与植入物表面之间的相互作用促进腐蚀过程。因此,自催化过程可导致种植体周围骨的加速周转。
    Interfaces between AISI 304 stainless steel screws and cranial bone were investigated after long-term implantation lasting for 42 years. Samples containing the interface regions were analyzed using state-of-the-art analytical techniques including secondary ion mass, Fourier-transform infrared, Raman, and X-ray photoelectron spectroscopies. Local samples for scanning transmission electron microscopy were cut from the interface regions using the focused ion beam technique. A chemical composition across the interface was recorded in length scales covering micrometric and nanometric resolutions and relevant differences were found between peri-implant and the distant cranial bone, indicating generally younger bone tissue in the peri-implant area. Furthermore, the energy dispersive spectroscopy revealed an 80 nm thick steel surface layer enriched by oxygen suggesting that the AISI 304 material undergoes a corrosion attack. The attack is associated with transport of metallic ions, namely, ferrous and ferric iron, into the bone layer adjacent to the implant. The results comply with an anticipated interplay between released iron ions and osteoclast proliferation. The interplay gives rise to an autocatalytic process in which the iron ions stimulate the osteoclast activity while a formation of fresh bone resorption sites boosts the corrosion process through interactions between acidic osteoclast extracellular compartments and the implant surface. The autocatalytic process thus may account for an accelerated turnover of the peri-implant bone.
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