Proteoglycans

蛋白聚糖
  • 文章类型: Journal Article
    目的:本研究的目的是研究成年人静脉注射免疫球蛋白(IVIG)引起的血清(1-3)-β-D-葡聚糖(BDG)的动态变化。
    方法:本研究包括2021年10月至2022年10月住院期间接受IVIG输注的患者。我们随机检查了每位患者的两个IVIG样品。在九个时间点收集血清样品:前(Tpre),立即(T1-0),第一天后6h(T1-1)和12h(T1-2);在IVIG输注期间,第二天立即(T2-0)和六小时后(T2-1),和IVIG输注后三天内(分别为Ta1,Ta2和Ta3)。采用Friedman检验进行统计分析。
    结果:共有来自19例患者的159份血清BDG纳入分析。IVIG的BDG含量范围为249μg/ml至4812μg/ml。患者在T1-0时血清BDG显着升高(176(113,291)pg/ml,p=0.002)和Ta1(310(199,470)pg/ml,p<0.001),与Tpre(41(38,65)pg/ml)相比。血清BDG(ΔBDG)的增量与IVIG的BDG浓度相关(Spearmanr=0.59,p=0.02)。肾功能指标异常的患者在Ta1(403(207,484)pg/ml)时血清ΔBDG值高于肾功能正常的患者(172(85,316)pg/ml,p=0.036)。
    结论:接受IVIG治疗的患者血清BDG值明显增高。BDG水平升高与IVIG的BDG含量和肾功能指标异常相关。
    OBJECTIVE: The purpose of this study was to investigate the dynamic changes in serum (1-3)-β-D-glucan (BDG) caused by intravenous immunoglobulins (IVIG) infusion in adults.
    METHODS: This study included patients who received IVIG infusion from October 2021 to October 2022 during hospitalization. We randomly examined two IVIG samples for every patient. Serum samples were collected at nine time points: before (Tpre), immediately (T1-0), 6h (T1-1) and 12h (T1-2) later on the first day; immediately (T2-0) and six hours later (T2-1) on the second day during IVIG infusion, and within three days after IVIG infusion (Ta1, Ta2, and Ta3, respectively). The Friedman test was used for statistical analysis.
    RESULTS: A total of 159 serum BDG from 19 patients were included in the analysis. The BDG content of IVIG ranged from 249 pg/ml to 4812 pg/ml. Patients had significantly elevated serum BDG on T1-0 (176 (113, 291) pg/ml, p = 0.002) and Ta1 (310 (199, 470) pg/ml, p < 0.001), compared with Tpre (41 (38, 65) pg/ml). The increments of serum BDG (ΔBDG) were associated with BDG concentration of IVIG (Spearman r = 0.59, p = 0.02). Individuals with abnormal renal function indexes showed higher serum ΔBDG values at Ta1 (403 (207, 484) pg/ml) than patients with normal renal function (172 (85, 316) pg/ml, p = 0.036).
    CONCLUSIONS: Patients who received IVIG had significantly higher serum BDG values. Elevated BDG levels correlate with BDG content of IVIG and abnormal renal function indexes.
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  • 文章类型: Journal Article
    基于细胞的牙髓再生过程中的新生血管形成过程难以研究。在这里,我们开发了一种模拟根管空间的管模型,并允许在体外直接可视化血管化过程。内皮样细胞(ECs)来源于引导人牙髓干细胞(DPSC)表达内皮细胞标志物CD144,vWF,使用VEGFR1和VEGFR2。人微血管内皮细胞(hMVEC)用作阳性对照。DPSC-EC在基质胶上形成类似于hMVEC的小管。将细胞在纤维蛋白原/凝血酶或小鼠血液中混合,并接种到96孔板的孔中或注射到锥形塑料管(长度为14mm,尖端开口的直径为1或2mm)中,其中较大的末端用MTA密封以模拟根管空间。将孔或管中的细胞/凝胶在体外孵育不同时间,并在显微镜下观察形态学变化。然后将样品固定并处理用于组织学分析以确定血管形成。细胞接种后1至3d,在培养物中观察到血管样网络。将96孔板中的细胞/凝胶维持长达25天。96孔板或试管中的hMVEC和DPSC-EC均显示细胞内液泡形成。一些细胞显示合并的大液泡,表明管腔形成。还观察到类似血管的管状结构。除了冠状部分中的一些样品(顶端直径Imm)之外,细胞在整个管中看起来是健康的。组织学分析还显示整个具有血管样结构的管样品中的浆状软组织。hMVEC比DPSC-EC形成更大的血管腔尺寸,而后者倾向于具有更多的腔和管状结构计数。我们得出结论,DPSC-EC可以形成血管结构,并在体外维持在3维纤维蛋白凝胶系统中。管模型似乎是模拟根管空间的适当且简单的系统,用于血管形成和牙髓再生研究。
    The process of neovascularization during cell-based pulp regeneration is difficult to study. Here we developed a tube model that simulates root canal space and allows direct visualization of the vascularization process in vitro. Endothelial-like cells (ECs) derived from guiding human dental pulp stem cells (DPSCs) into expressing endothelial cell markers CD144, vWF, VEGFR1, and VEGFR2 were used. Human microvascular endothelial cells (hMVECs) were used as a positive control. DPSC-ECs formed tubules on Matrigel similar to hMVECs. Cells were mixed in fibrinogen/thrombin or mouse blood and seeded into wells of 96-well plates or injected into a tapered plastic tube (14 mm in length and 1 or 2 mm diameter of the apex opening) with the larger end sealed with MTA to simulate root canal space. Cells/gels in wells or tubes were incubated for various times in vitro and observed under the microscope for morphological changes. Samples were then fixed and processed for histological analysis to determine vessel formation. Vessel-like networks were observed in culture from 1 to 3 d after cell seeding. Cells/gels in 96-well plates were maintained up to 25 d. Histologically, both hMVECs and DPSC-ECs in 96-well plates or tubes showed intracellular vacuole formation. Some cells showed merged large vacuoles indicating the lumenization. Tubular structures were also observed resembling blood vessels. Cells appeared healthy throughout the tube except some samples (1 mm apical diameter) in the coronal third. Histological analysis also showed pulp-like soft tissue throughout the tube samples with vascular-like structures. hMVECs formed larger vascular lumen size than DPSC-ECs while the latter tended to have more lumen and tubular structure counts. We conclude that DPSC-ECs can form vascular structures and sustained in the 3-dimensional fibrin gel system in vitro. The tube model appears to be a proper and simple system simulating the root canal space for vascular formation and pulp regeneration studies.
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  • 文章类型: Journal Article
    与成年半月板不同,胎儿半月板具有强大的愈合能力。成年半月板的致密而坚硬的基质为细胞迁移提供了生物物理屏障,胎儿半月板中不存在。受发育特征的启发,将成年半月板的基质改造成胎儿状,松散和柔软的微环境有机会促进修复,尤其是在无血管区。
    将成年半月板的致密而坚硬的基质修改为胎儿状,松散和柔软的微环境可以增强细胞迁移到泪液界面和随后强大的愈合能力。
    对照实验室研究。
    用透明质酸酶或胶原酶处理新鲜的猪半月板。评估胶原纤维的密度和排列。通过组织学评估蛋白聚糖和胶原蛋白的降解。检查半月板内的细胞迁移或外源细胞向半月板的浸润。具有相对大孔的树枝状二氧化硅纳米颗粒用于包封透明质酸酶以快速释放。具有相对小的孔的介孔二氧化硅纳米颗粒用于包封转化生长因子-β3(TGF-β3)以用于缓慢释放。总共包括24只成熟的雄性兔。在内侧半月板的无血管区中制备纵向垂直撕裂(长度为0.5cm)。用缝线修复了撕裂,除了空白二氧化硅纳米颗粒外,用缝合线修复,或除了释放透明质酸酶和TGF-β3的二氧化硅纳米颗粒外,用缝合线修复。在术后12个月处死动物。通过宏观和组织学评估半月板修复。
    透明质酸酶处理后胶原蛋白束之间的间隙增加,而胶原酶处理导致胶原破坏。透明质酸酶处理后蛋白聚糖以剂量依赖性方式降解,但胶原蛋白的完整性得以维持。透明质酸酶处理增强了半月板组织内细胞的迁移和浸润。最后,在原位纵向垂直撕裂模型中,纤维蛋白凝胶和包裹透明质酸酶和TGF-β3的二氧化硅纳米颗粒递送系统的应用增强了半月板修复反应。
    透明质酸酶和TGF-β3的梯度释放消除了细胞迁移的生物物理障碍,创造一个像胎儿一样的,宽松和软的微环境,增强了修复细胞的纤维软骨表型,促进基质的合成和组织的整合。
    将成年基质修改为胎儿状,通过透明质酸酶和TGF-β3的局部梯度释放,松软的微环境增强了半月板的愈合能力。
    Unlike the adult meniscus, the fetal meniscus possesses robust healing capacity. The dense and stiff matrix of the adult meniscus provides a biophysical barrier for cell migration, which is not present in the fetal meniscus. Inspired by developmental characteristics, modifying the matrix of the adult meniscus into a fetal-like, loose and soft microenvironment holds opportunity to facilitate repair, especially in the avascular zone.
    Modifying the dense and stiff matrix of the adult meniscus into a fetal-like, loose and soft microenvironment could enhance cell migration to the tear interface and subsequent robust healing capacity.
    Controlled laboratory study.
    Fresh porcine menisci were treated with hyaluronidase or collagenase. The density and arrangement of collagen fibers were assessed. The degradation of proteoglycans and collagen was evaluated histologically. Cell migration within the meniscus or the infiltration of exogenous cells into the meniscus was examined. Dendritic silica nanoparticles with relatively large pores were used to encapsulate hyaluronidase for rapid release. Mesoporous silica nanoparticles with relatively small pores were used to encapsulate transforming growth factor-beta 3 (TGF-β3) for slow release. A total of 24 mature male rabbits were included. A longitudinal vertical tear (0.5 cm in length) was prepared in the avascular zone of the medial meniscus. The tear was repaired with suture, repaired with suture in addition to blank silica nanoparticles, or repaired with suture in addition to silica nanoparticles releasing hyaluronidase and TGF-β3. Animals were sacrificed at 12 months postoperatively. Meniscal repair was evaluated macroscopically and histologically.
    The gaps between collagen bundles increased after hyaluronidase treatment, while collagenase treatment resulted in collagen disruption. Proteoglycans degraded after hyaluronidase treatment in a dose-dependent manner, but collagen integrity was maintained. Hyaluronidase treatment enhanced the migration and infiltration of cells within meniscal tissue. Last, the application of fibrin gel and the delivery system of silica nanoparticles encapsulating hyaluronidase and TGF-β3 enhanced meniscal repair responses in an orthotopic longitudinal vertical tear model.
    The gradient release of hyaluronidase and TGF-β3 removed biophysical barriers for cell migration, creating a fetal-like, loose and soft microenvironment, and enhanced the fibrochondrogenic phenotype of reparative cells, facilitating the synthesis of matrix and tissue integration.
    Modifying the adult matrix into a fetal-like, loose and soft microenvironment via the local gradient release of hyaluronidase and TGF-β3 enhanced the healing capacity of the meniscus.
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  • 文章类型: Journal Article
    与蛋白聚糖交织的高度组织化的胶原纤维形成角膜的关键结构并促进其透明度。意外伤害造成的角膜疤痕,手术,或者感染改变了这个高度组织化的组织,造成严重后果,包括失明。没有有效和安全地治疗过度角膜瘢痕的药物或手术方法。因此,我们测试了合理设计的抗胶原抗体(ACA)的抗角膜瘢痕作用,该抗体的抗纤维化作用已在非眼模型中得到证实.利用带有切口角膜伤口的兔子模型,我们分析了ACA对瘢痕新生组织中富含胶原和蛋白聚糖的细胞外基质形成的影响。我们使用显微镜和光谱技术来量化这些成分,并测量表征胶原纤维结构和组织的关键参数。此外,我们分析了正常角膜和愈合角膜中胶原蛋白和蛋白聚糖的空间分布。我们的研究表明,在瘢痕新组织中合成的分析分子的质量和数量发生了显着变化。结果表明,这些变化超出了切口边缘。它还显示了ACA对定义适当角膜结构的一些关键参数的积极影响。这项初步研究为将来针对角膜细胞外瘢痕基质组装的治疗方法的测试提供了垫脚石。
    Highly organized collagen fibrils interlacing with proteoglycans form the crucial architecture of the cornea and facilitate its transparency. Corneal scarring from accidental injury, surgery, or infection alters this highly organized tissue, causing severe consequences, including blindness. There are no pharmacological or surgical methods to effectively and safely treat excessive corneal scarring. Thus, we tested the anticorneal scarring utility of a rationally designed anticollagen antibody (ACA) whose antifibrotic effects have already been demonstrated in nonocular models. Utilizing a rabbit model with an incisional corneal wound, we analyzed ACA\'s effects on forming collagen and proteoglycan-rich extracellular matrices in scar neotissue. We used microscopic and spectroscopic techniques to quantify these components and measure crucial parameters characterizing the structure and organization of collagen fibrils. Moreover, we analyzed the spatial distribution of collagen and proteoglycans in normal and healing corneas. Our study demonstrated significant changes in the quality and quantity of the analyzed molecules synthesized in scar neotissue. It showed that these changes extend beyond incision margins. It also showed ACA\'s positive impact on some crucial parameters defining proper cornea structure. This pilot study provides a stepping stone for future tests of therapeutic approaches that target corneal extracellular scar matrix assembly.
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  • 文章类型: Observational Study
    背景:与脓毒症相关的肺微血管内皮糖萼(EGCX)的破坏会产生脆弱的内皮表面,导致急性呼吸窘迫综合征(ARDS)的发展。EGCX的成分流入流通,糖胺聚糖和蛋白聚糖,可以作为内皮功能障碍的生物标志物。我们试图确定脓毒症相关小儿ARDS(PARDS)患儿血浆EGCX降解产物的模式,并测试它们与临床结果的关联。
    方法:我们回顾性分析了一项前瞻性队列(2018-2020年)接受有创机械通气治疗急性呼吸衰竭≥72h的儿童(≥1个月至<18岁)。从父母队列中选择有和无败血症相关PARDS的儿童并进行比较。在登记时收集血液。血浆糖胺聚糖二糖类(硫酸乙酰肝素,硫酸软骨素,和透明质酸)和硫酸化亚型(硫酸乙酰肝素和硫酸软骨素)使用液相色谱串联质谱法进行定量。通过免疫测定法测量血浆蛋白聚糖(syndecan-1)。
    结果:在39名机械通气儿童(29名和10名无败血症相关PARDS)中,脓毒症相关PARDS患者的硫酸乙酰肝素水平较高(中位数639ng/mL[四分位距,IQR421-902]vs311[IQR228-461])和syndecan-1(中位数146ng/mL[IQR32-315]vs8[IQR8-50]),两者p=0.01。硫酸乙酰肝素亚型分析显示,脓毒症相关PARDS患儿中N-硫酸化二糖水平的比例更高(p=0.01)。通过四分位数增加N-硫酸化二糖水平与严重PARDS(n=9/29)相关,四分位数最高,包括>60%的严重PARDS患者(趋势测试,p=0.04)。在脓毒症相关的PARDS患儿中,较高的总硫酸乙酰肝素和N-硫酸二糖水平与较少的28天无呼吸机天数独立相关(均p<0.05)。
    结论:脓毒症相关PARDS患儿血浆中硫酸乙酰肝素二糖和syndecan-1水平较高,提示EGCX降解生物标志物可提供对内皮功能障碍和PARDS病理生物学的认识。
    BACKGROUND: Sepsis-associated destruction of the pulmonary microvascular endothelial glycocalyx (EGCX) creates a vulnerable endothelial surface, contributing to the development of acute respiratory distress syndrome (ARDS). Constituents of the EGCX shed into circulation, glycosaminoglycans and proteoglycans, may serve as biomarkers of endothelial dysfunction. We sought to define the patterns of plasma EGCX degradation products in children with sepsis-associated pediatric ARDS (PARDS), and test their association with clinical outcomes.
    METHODS: We retrospectively analyzed a prospective cohort (2018-2020) of children (≥1 month to <18 years of age) receiving invasive mechanical ventilation for acute respiratory failure for ≥72 h. Children with and without sepsis-associated PARDS were selected from the parent cohort and compared. Blood was collected at time of enrollment. Plasma glycosaminoglycan disaccharide class (heparan sulfate, chondroitin sulfate, and hyaluronan) and sulfation subtypes (heparan sulfate and chondroitin sulfate) were quantified using liquid chromatography tandem mass spectrometry. Plasma proteoglycans (syndecan-1) were measured through an immunoassay.
    RESULTS: Among the 39 mechanically ventilated children (29 with and 10 without sepsis-associated PARDS), sepsis-associated PARDS patients demonstrated higher levels of heparan sulfate (median 639 ng/mL [interquartile range, IQR 421-902] vs 311 [IQR 228-461]) and syndecan-1 (median 146 ng/mL [IQR 32-315] vs 8 [IQR 8-50]), both p = 0.01. Heparan sulfate subtype analysis demonstrated greater proportions of N-sulfated disaccharide levels among children with sepsis-associated PARDS (p = 0.01). Increasing N-sulfated disaccharide levels by quartile were associated with severe PARDS (n = 9/29) with the highest quartile including >60% of the severe PARDS patients (test for trend, p = 0.04). Higher total heparan sulfate and N-sulfated disaccharide levels were independently associated with fewer 28-day ventilator-free days in children with sepsis-associated PARDS (all p < 0.05).
    CONCLUSIONS: Children with sepsis-associated PARDS exhibited higher plasma levels of heparan sulfate disaccharides and syndecan-1, suggesting that EGCX degradation biomarkers may provide insights into endothelial dysfunction and PARDS pathobiology.
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  • 文章类型: Journal Article
    背景:人类口腔粘膜的组织学与功能和解剖位置密切相关,正确表征人类咀嚼口腔粘膜可能对牙周病理学非常有用。
    目的:在目前的工作中,我们进行了一项全面的研究,以确定使用光学和电子显微镜检查的偏角化(POM)和正交化(OOM)咀嚼人口腔粘膜的主要组织学特征。
    方法:要执行此操作,我们使用了几种组织学,组织化学和免疫组织化学方法来检测上皮的主要市场,基底膜和结缔组织水平。
    结果:我们的结果表明POM和OOM具有许多组织学相似性,如预期。然而,在POM的上皮层观察到重要的差异,明显比OOM中的上皮层厚,特别是由于棘层的细胞数量较多。与POM相比,CK10和聚丝蛋白的表达模式揭示了OOM中强烈的信号表达。OOM基质中的胶原蛋白和蛋白聚糖比POM中的更丰富。血管和基底膜没有发现差异。
    结论:这些结果可能有助于更好地了解影响人类咀嚼性口腔粘膜的病理状况。此外,这些发现可能有助于通过组织工程技术产生不同类型的口腔粘膜。
    人咀嚼性口腔黏膜的显微镜特征显示出两者的重要差异,上皮和基质水平。假性咀嚼人口腔粘膜发挥较厚的上皮层,尤其是,与角化的人口腔粘膜相比,在棘层。与角化咀嚼人类口腔粘膜相比,细胞角蛋白10和聚丝团蛋白人类上皮标志物在正交咀嚼人类口腔粘膜中强烈表达。在基质层面,正交咀嚼的人口腔黏膜比半咀嚼的口腔黏膜表现出更高的胶原蛋白和蛋白聚糖水平。对咀嚼性口腔黏膜组织学特征的深入了解可以使人们更好地了解口腔黏膜病理和晚期治疗方法。
    BACKGROUND: Histology of human oral mucosa is closely related with its function and anatomical location, and a proper characterization of the human masticatory oral mucosa could be very useful in periodontal pathology.
    OBJECTIVE: In the present work, we have carried out a comprehensive study in order to determine the main histological features of parakeratinized (POM) and orthokeratinized (OOM) masticatory human oral mucosa using light and electron microscopy.
    METHODS: To perform this, we have used several histological, histochemical and immunohistochemical methods to detect key markets at the epithelial, basement membrane and connective tissue levels.
    RESULTS: Our results demonstrated that POM and OOM share many histological similarities, as expected. However, important differences were observed at the epithelial layer of POM, that was significantly thicker than the epithelial layer found in OOM, especially due to a higher number of cells at the stratum spinosum. The expression pattern of CK10 and filaggrin revealed intense signal expression in OOM as compared to POM. Collagen and proteoglycans were more abundant in OOM stroma than in POM. No differences were found for blood vessels and basement membrane.
    CONCLUSIONS: These results may contribute to a better understanding of the pathological conditions affecting the human masticatory oral mucosa. In addition, these findings could be useful for the generation of different types of oral mucosa by tissue engineering techniques.
    UNASSIGNED: Microscopical features of parakeratinized and orthokeratinized masticatory human oral mucosa showed important differences at both, epithelial and stromal levels. Parakeratinized masticatory human oral mucosa exert thicker epithelial layer, especially, at the stratum spinosum in comparison to orthokeratinized human oral mucosa. Cytokeratin 10 and filaggrin human epithelial markers were intensively expressed in orthokeratinized masticatory human oral mucosa in comparison to parakeratinized masticatory human oral mucosa. At the stromal level, orthokeratinized masticatory human oral mucosa exhibit higher levels of collagen and proteoglycans than parakeratinized masticatory oral mucosa. The deep knowledge of histological features of masticatory oral mucosa could lead to a better understanding of oral mucosa pathology and advanced treatments.
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  • 文章类型: Journal Article
    目的:用傅立叶变换红外(FITR)光谱成像检查大鼠下颌髁突软骨(MCC),以研究衰老的影响,雌激素水平和饮食负荷对MCC结构的影响。
    方法:将5和14月龄的Sprague-Dawley大鼠(n=96)按年龄分为12个亚组,雌激素状态(卵巢切除[OVX],非卵巢切除[非OVX)])和饮食(硬,正常,软)。用FTIR光谱成像检查MCC的样本以量化胶原蛋白和蛋白聚糖的分布。MCC矢状分为三段:前段,最上和后。从每个片段中,采用N路方差分析(ANOVA)对各组不同软骨深度的胶原和蛋白聚糖含量进行统计学比较.
    结果:在MCC的前段深层和后段中间层,胶原蛋白含量的量与年龄显着相关。在最高级的深层,胶原蛋白含量也随着年龄的增长而增加。当膳食负荷增加时,蛋白聚糖含量显著增加,MCC最上段深层雌激素水平下降。
    结论:老龄化,雌激素水平和饮食负荷的改变对大鼠MCC的胶原蛋白和蛋白聚糖的位置和含量有显着影响。老化显著增加上段和后段胶原含量,在老年软饮食大鼠中最高。雌激素水平的降低和饮食负荷的增加增加了蛋白聚糖的含量。
    OBJECTIVE: Mandibular condylar cartilage (MCC) of the rat was examined with the Fourier-transform infrared (FITR) spectroscopic imaging to study the effects of ageing, oestrogen level and altered dietary loading on the structure of MCC.
    METHODS: The Sprague-Dawley rats (n = 96) aged 5 and 14 months were divided into 12 subgroups according to age, oestrogen status (ovariectomized [OVX], non-ovariectomized [non-OVX)]) and diet (hard, normal, soft). Specimens of the MCC were examined with FTIR spectroscopic imaging to quantify the distribution of collagens and proteoglycans. MCC was divided sagittally into three segments: anterior, most superior and posterior. From each segment, the collagen and proteoglycan contents at different depths of cartilage were statistically compared between the groups using an N-way analysis of variance (ANOVA).
    RESULTS: The amount of collagen content was significantly associated with old age in the deep layer of the anterior segment and in the middle layer of the posterior segment of MCC. In the deep layer of the most superior segment, the collagen content also increased with ageing. The amount of proteoglycan content increased significantly when dietary loading increased, and the oestrogen level decreased in the deep layer of the most superior segment of MCC.
    CONCLUSIONS: Ageing, oestrogen level and altered dietary loading have a significant effect on the location and content of collagens and proteoglycans of rat MCC. Ageing significantly increased the amount of collagen content in the superior and posterior segments, being highest in the older soft-diet rats. Decreased oestrogen levels and increased dietary loading increased the amount of proteoglycan content.
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  • 文章类型: Journal Article
    目的:β-D-葡聚糖(BDG)检测已被建议用于支持念珠菌血症和侵袭性念珠菌病的诊断。到目前为止,重症监护病房(ICU)中危重高危患者的实际收益尚未得到证实。
    方法:在接受疑似侵袭性念珠菌病(IC)的经验性棘白菌素治疗的ICU患者中,使用富士胶片Wakoβ-葡聚糖测试进行系列BDG测试,从施用棘白菌素的第一天开始,之后每24-48小时。使用一系列截止值确定单次测试和连续测试策略的诊断准确性。此外,我们比较了这些测试策略在将结果作为额外预测因子引入多变量逻辑回归模型以控制已确定的IC危险因素时的附加值.
    结果:总共174名ICU患者,其中46例(25.7%)被归类为IC病例,包括在我们的研究中。初始BDG测试显示中等灵敏度(74%,95CI59-86%)和特异性差(45%,95%CI36-54%)的IC,通过后续测试很难得到改善。虽然原始BDG值或以非常高的阈值获得的测试结果改善了我们用于IC的多变量逻辑回归模型的预测性能,制造商提出的低水平截止的单一或系列测试均未显示出实质性的好处。
    结论:在我们对念珠菌菌血症或侵袭性念珠菌病高风险的危重重症监护患者的研究中,BDG检测的诊断准确性不足以为治疗决策提供依据.仅对于具有非常高的BDG值的病例实现了改进的分类。
    OBJECTIVE: Beta-D-Glucan (BDG) testing has been suggested to support the diagnosis of candidemia and invasive candidiasis. The actual benefit in critically ill high-risk patients in intensive care units (ICU) has not been verified so far.
    METHODS: In ICU patients receiving empirical echinocandin treatment for suspected invasive candidiasis (IC), serial BDG testing using the Fujifilm Wako Beta-Glucan Test was performed, starting on the first day of echinocandin administration and every 24-48 h afterwards. Diagnostic accuracy was determined for single testing and serial testing strategies using a range of cut-off values. In addition, we compared the added value of these testing strategies when their results were introduced as additional predictors into a multivariable logistic regression model controlling for established risk factors of IC.
    RESULTS: A total of 174 ICU patients, forty-six of which (25.7%) classified as cases of IC, were included in our study. Initial BDG testing showed moderate sensitivity (74%, 95%CI 59-86%) and poor specificity (45%, 95% CI 36-54%) for IC which could hardly be improved by follow-up testing. While raw BDG values or test results obtained with very high thresholds improved the predictive performance of our multivariable logistic regression model for IC, neither single nor serial testing with the manufacturer-proposed low-level cut-off showed substantial benefit.
    CONCLUSIONS: In our study of critically ill intensive care patients at high risk for candidemia or invasive candidiasis, diagnostic accuracy of BDG testing was insufficient to inform treatment decisions. Improved classification was only achieved for cases with very high BDG values.
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  • 文章类型: Journal Article
    目的:目前的实验方法无法阐明骨关节炎(OA)变性过程中适应不良变化对主要软骨成分的影响。在硅方法中,然而,允许创建“虚拟敲除”案例,以特定于成分的方式阐明这些影响。我们使用这种方法来研究与以下OA病因相关的不同机械负荷下软骨退化的主要机制:(i)退化软骨的生理负荷,(ii)健康完整软骨的损伤负荷和(iii)具有局灶性缺损的软骨的生理负荷。
    方法:我们使用最近开发的软骨自适应复位退变(CARED)框架来模拟与原发性和继发性OA相关的软骨退变(OA病例(i)-(iii))。CARED结合了OA中组织水平软骨退变机制的数值描述,即,胶原蛋白降解,胶原蛋白重新定向,固定电荷密度损失和组织水化增加后的机械负荷。我们通过在三个OA案例中的每个案例中一次一个地停用这些退化过程来创建“虚拟敲除”场景。
    结果:在退化软骨的完整和生理负荷的有害负荷中,胶原蛋白降解通过固定电荷密度损失和组织水化上升驱动退行性变化。相比之下,后两种机制在局灶性缺损软骨模型中更为突出。
    结论:虚拟敲除模型显示,完整软骨的损伤负荷和退化软骨的生理负荷可引起胶原网络的初始退行性变化,然而,在存在局灶性软骨缺损的情况下,机械加载最初会导致PG耗尽,在胶原蛋白原纤维网络发生变化之前。
    Current experimental approaches cannot elucidate the effect of maladaptive changes on the main cartilage constituents during the degeneration process in osteoarthritis (OA). In silico approaches, however, allow creating \'virtual knock-out\' cases to elucidate these effects in a constituent-specific manner. We used such an approach to study the main mechanisms of cartilage degeneration in different mechanical loadings associated with the following OA etiologies: (1) physiological loading of degenerated cartilage, (2) injurious loading of healthy intact cartilage and (3) physiological loading of cartilage with a focal defect.
    We used the recently developed Cartilage Adaptive REorientation Degeneration (CARED) framework to simulate cartilage degeneration associated with primary and secondary OA (OA cases (1)-(3)). CARED incorporates numerical description of tissue-level cartilage degeneration mechanisms in OA, namely, collagen degradation, collagen reorientation, fixed charged density loss and tissue hydration increase following mechanical loading. We created \'virtual knock-out\' scenarios by deactivating these degenerative processes one at a time in each of the three OA cases.
    In the injurious loading of intact and physiological loading of degenerated cartilage, collagen degradation drives degenerative changes through fixed charge density loss and tissue hydration rise. In contrast, the two later mechanisms were more prominent in the focal defect cartilage model.
    The virtual knock-out models reveal that injurious loading to intact cartilage and physiological loading to degenerated cartilage induce initial degenerative changes in the collagen network, whereas, in the presence of a focal cartilage defect, mechanical loading initially causes proteoglycans (PG) depletion, before changes in the collagen fibril network occur.
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  • 文章类型: Journal Article
    亚细胞分级分离是设计用于研究细胞内成分的各种实验方法的介绍性步骤。像膜和细胞器系统。已分离出富含哺乳动物细胞高尔基体膜的亚细胞部分,以解决蛋白质的定位和活性,包括酶,为了研究细胞内膜运输机制,并重建与高尔基体相关的体外细胞过程。这里,我描述了通过亚细胞分馏纯化高尔基膜的方法,为了测定高尔基体囊泡对核苷酸硫酸盐(PAPS)的摄取,并测量硫酸盐掺入到体外合成的糖胺聚糖中。
    Subcellular fractionation is an introductory step in a variety of experimental approaches designed to study intracellular components, like membranes and organelle systems. Subcellular fractions enriched in membranes of the Golgi apparatus of mammalian cells have been isolated to address localization and activity of proteins, including enzymes, to study intracellular membrane transport mechanisms, and to reconstitute in vitro cellular processes associated with the Golgi apparatus. Here, I describe methods to purify Golgi membranes by subcellular fractionation, to assay nucleotide sulfate (PAPS) uptake into Golgi vesicles, and to measure sulfate incorporation into in vitro synthesized glycosaminoglycans.
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