Fluorescein

荧光素
  • 文章类型: Journal Article
    目的:由连续的脑脊液(CSF)引起的复发性鼻漏,解剖学上分离的颅底缺损在文献中很少报道。管理和病因均未得到充分调查。我们在此提供一个说明性的案例和有关病因学的文献的系统综述,诊断,和管理这种罕见的现象。
    方法:进行了系统的文献检索,寻找报道有多个颅底缺损的连续脑脊液漏的文章。纳入文章的数据是描述性报道的,纳入研究的质量采用GRADE评估.
    结果:一位71岁的女性患者,在我们的机构中出现了由于岩骨左侧纵向骨折导致的外伤性鼻漏和左侧耳漏。在初次手术修复和十周无症状间隔后,脑脊液鼻漏复发。影像学检查显示,蝶窦外侧隐窝先前存在的对侧脑膜脑膨出,在最初的创伤性裂伤后很可能导致复发的CSF鼻漏。该缺陷已成功治疗。文献检索确定了366份报告,其中6例纳入系统审查,共10例。在8/10例中,质量被认为是好的。原发性和序贯性CSF渗漏最常见的位置是沿着蝶骨(4/10和5/10患者,分别)。除一篇出版物外,所有出版物都报道了脑膜(脑)细胞的存在是连续CSF泄漏的原因。
    结论:由于解剖学上分离的顺序颅底病变引起的复发性CSF鼻漏的发生仍然是一种罕见的尚未描述的现象。因此,应考虑重新评估影像学研究和结构化的诊断工作,以检测与原发性病变无关的连续CSF泄漏。
    OBJECTIVE: Recurrent cerebrospinal fluid (CSF) rhinorrhea caused by sequential, anatomically separated skull base defects are rarely reported in the literature. Neither management nor etiology are sufficiently investigated. We herein present an illustrative case and a systematic review of the literature regarding etiology, diagnostics, and management of this rare phenomenon.
    METHODS: A systematic literature search looking for articles reporting sequential CSF-leaks with multiple skull base defects was performed. Data from included articles was descriptively reported, the quality of the included studies was assessed with GRADE.
    RESULTS: A 71-year-old female patient with posttraumatic rhino- and left-sided otorrhea due to a left-sided longitudinal fracture of the petrous bone presented at our institution. After initial surgical repair and a ten-week symptom-free interval, CSF-rhinorrhea reoccurred. Imaging review revealed a pre-existing contralateral meningoencephalocele of the lateral sphenoid recess causing recurrent CSF-rhinorrhea most likely after initial traumatic laceration. The defect was successfully treated. Literature search identified 366 reports, six of which were included in the systematic review with a total of ten cases. Quality was deemed good in 8/10 cases. The most common location for primary and sequential CSF-leaks was along the sphenoid bone (4/10 and 5/10 patients, respectively). All publications except one reported the presence of a meningo(encephalo)cele as cause of the sequential CSF-leak.
    CONCLUSIONS: Occurrence of recurrent CSF-rhinorrhea due to an anatomically separated sequential skull base lesion remains a rare yet described phenomenon. Reassessment of imaging studies and a structured diagnostic work-up to detect sequential CSF-leaks independent of the primary lesion should therefore be considered.
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  • 文章类型: Journal Article
    目的:比较眼表疾病指数(OSDI)问卷与干眼症的客观测试。
    方法:一项前瞻性观察性研究。研究的地点和持续时间:眼科,NigdeOmerHalisdemir大学,Nigde,Turkiye,2022年6月9日至12月31日。
    方法:纳入临床诊断为干眼病(DED)的323只眼。通过角膜和结膜荧光素染色的牛津分类对受试者进行评估,Schirmer我测试,和荧光素撕裂破裂时间(TBUT)。用OSDI解释患者的症状,并分析症状和客观标志物的相关性。
    结果:任何客观体征之间都没有显着关联(SchirmerI,TBUT,和牛津),和OSDI(分别为p=0.26、0.52、0.18和)。SchirmerI评分与TBUT呈显著正相关(p<0.001,r=0.21),与牛津量表呈显著负相关(p<0.001,r=-0.19)。TBUT与Oxford量表之间存在统计学负相关(p<0.001,r=-0.37)。
    结论:除了Schirmer检验,TBUT和Oxford量表是诊断DED的有效工具。症状标记,例如OSDI在诊断DED和确定其严重程度方面可能具有较低的可靠性。诊断测试对于检测无症状或可忽略的较不严重的干眼症很重要。
    背景:干眼症,诊断,眼表疾病指数(OSDI),撕裂破裂时间(TBUT),牛津分级量表,我测试的Schirmer。
    OBJECTIVE: To compare the ocular surface disease index (OSDI) questionnaire with objective tests in dry eye disease.
    METHODS: A prospective observational study. Place and Duration of the Study: Department of Ophthalmology, Nigde Omer Halisdemir University, Nigde, Turkiye, from 9th June to 31st December 2022.
    METHODS: All clinically diagnosed 323 eyes of patients with dry eye disease (DED) were included. The subjects were evaluated by the Oxford classification of corneal and conjunctival fluorescein staining, Schirmer I test, and fluorescein tear breakup time (TBUT). Symptoms of the patients were interpreted with OSDI and correlations of symptoms and objective markers were analysed.
    RESULTS: There was no significant association between any objective signs (Schirmer I, TBUT, and Oxford), and OSDI (p = 0.26, 0.52, 0.18, and respectively). Schirmer I score showed a significant positive correlation with TBUT (p <0.001, r = 0.21) and a significant negative correlation with Oxford scale (p <0.001, r = -0.19). There was a statistically negative correlation between TBUT and Oxford scale (p <0.001, r = -0.37).
    CONCLUSIONS: Except for the Schirmer test, TBUT and Oxford scale are effective tools in the diagnosis of DED. Symptom markers, such as OSDI may have lower reliability in diagnosing DED and determining its severity. Diagnostic tests are important in the detection of asymptomatic or less severe dry eye disease that can be ignored.
    BACKGROUND: Dry eye disease, Diagnosis, Ocular surface disease index (OSDI), Tear breakup time (TBUT), Oxford grading scale, Schirmer I test.
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  • 文章类型: Journal Article
    为了建立施加在血迹上的热条件与增强技术的可视化效果之间的相关性,红外摄影和四种化学增强试剂用于可视化热暴露后的血迹。选择黑色瓷砖作为基板,以加强可视化挑战,锥形量热计作为标准化的加热源,以控制热条件。与标准摄影相比,红外摄影被证明是化学试剂的宝贵补充,在热暴露后可视化血迹方面显示出明显的优势。然而,值得注意的是,当显示的血迹升高时,红外图像达不到标准图像,压花形态或血迹在特定条件下几乎消失。发现增强效果与施加在血迹上的热条件密切相关,加热过程中血迹的形态演变也影响了化学增强效果,特别是当凸起形态形成时,并且观察到试剂在去除凸起的致密壳后更有效。在选定的四种化学增强试剂中,荧光素表现得非常好,即使在641°C加热10分钟的血迹也能保持其有效性。TMB显示了其在396°C加热5分钟和在310°C加热20分钟的血迹的可视化能力。之后跟随BLUESTAR®,而鲁米诺表现最差。施加在血迹上的热条件与增强技术的相应可视化效果之间的相关性为检测火灾场景中的血迹提供了重要参考。
    To establish the correlation between thermal conditions imposed on bloodstains and visualizing effect of enhancement techniques, infrared photography and four chemical enhancement reagents were used to visualize bloodstains following thermal exposure. A black tile was selected as the substrate to intensify the visualization challenge, with a Cone Calorimeter serving as the standardized heating source to control thermal conditions. Compared with standard photography, infrared photography is proven to be a valuable complement to chemical reagents, showing significant advantages in visualizing bloodstains after thermal exposure. However, it is worth noting that infrared image fell short of standard image when bloodstains displayed raised, embossed morphology or when bloodstains almost disappeared under specific conditions. The enhancement effectiveness was found to be strongly correlated with thermal conditions imposed on bloodstains, and the morphology evolution of bloodstains during heating affected the chemical enhancement effect additionally, especially when the bulge morphology was formed, and it was observed that reagents were more effective after removing the dense shell of the bulge. Among the four selected chemical enhancement reagents, fluorescein performed exceptionally well, maintaining its effectiveness even for bloodstains heated at 641°C for 10 min. TMB demonstrated its visualizing ability for bloodstains heated at 396°C for 5 min and heated at 310°C for 20 min. BLUESTAR® followed afterwards, while luminol performed worst. The correlation between thermal conditions imposed on bloodstains and the corresponding visualizing effectiveness of enhancement techniques provides important references for detecting bloodstains at fire scenes.
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  • 文章类型: Journal Article
    低分子量亲水性药物的控释,当地管理,允许在目标部位维持高浓度,减少全身副作用,并提高患者的依从性。可注射的水凝胶通常用作载体。然而,低分子量亲水性药物的缓释很难实现,主要是由于药物快速扩散出药物递送系统。在这里,我们提出了一种完全基于脂质体自组装的可注射和自修复水凝胶。脂质体的凝胶化,在不损害其结构完整性的情况下,通过改变胆固醇含量和表面电荷诱导。小的亲水分子,荧光素钠,将其装载在脂质体外空间内或包封到脂质体的水性核心中。这种封装策略能够实现受控和可调的释放曲线,取决于凝胶的机械强度。水凝胶具有高的机械强度,最小的肿胀,缓慢降解。脂质体基水凝胶具有延长的体内机械稳定性,且无局部不良反应。这项工作提出了一类新的可注射水凝胶,有望作为通用的药物递送系统。重要性声明:水凝胶的多孔性对递送小型亲水性药物提出了挑战,通常导致初始爆发释放并缩短释放持续时间。这个问题对于物理交联的水凝胶尤其明显,因为它们的基质可以迅速膨胀和消散,但即使在水凝胶中的聚合物是共价交联的情况下,小分子可以通过其多孔网快速释放。在这里,我们提出了一种完全基于脂质体自组装的可注射自修复水凝胶。小的亲水分子被截留在脂质体外空间内或加载到脂质体的水性核心中,允许控制和可调的释放配置文件。
    Controlled release of low molecular weight hydrophilic drugs, administered locally, allows maintenance of high concentrations at the target site, reduces systemic side effects, and improves patient compliance. Injectable hydrogels are commonly used as a vehicle. However, slow release of low molecular weight hydrophilic drugs is very difficult to achieve, mainly due to a rapid diffusion of the drug out of the drug delivery system. Here we present an injectable and self-healing hydrogel based entirely on the self-assembly of liposomes. Gelation of liposomes, without damaging their structural integrity, was induced by modifying the cholesterol content and surface charge. The small hydrophilic molecule, sodium fluorescein, was loaded either within the extra-liposomal space or encapsulated into the aqueous cores of the liposomes. This encapsulation strategy enabled the achievement of controlled and adjustable release profiles, dependent on the mechanical strength of the gel. The hydrogel had a high mechanical strength, minimal swelling, and slow degradation. The liposome-based hydrogel had prolonged mechanical stability in vivo with benign tissue reaction. This work presents a new class of injectable hydrogel that holds promise as a versatile drug delivery system. STATEMENT OF SIGNIFICANCE: The porous nature of hydrogels poses a challenge for delivering small hydrophilic drug, often resulting in initial burst release and shorten duration of release. This issue is particularly pronounced with physically crosslinked hydrogels, since their matrix can swell and dissipate rapidly, but even in cases where the polymers in the hydrogel are covalently cross-linked, small molecules can be rapidly released through its porous mesh. Here we present an injectable self-healing hydrogel based entirely on the self-assembly of liposomes. Small hydrophilic molecules were entrapped inside the extra-liposomal space or loaded into the aqueous cores of the liposomes, allowing controlled and tunable release profiles.
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  • 文章类型: Journal Article
    清醒开颅术(AC)可最大程度地切除雄辩的大脑区域的病变,同时保留功能。术中使用荧光素钠(NaFl)的肿瘤勾画有利于全切除。与AC一起使用时,它可能允许安全的切除,而不会增加术后神经功能缺损的风险。该研究调查了NaFl和AC的联合使用用于脑转移患者的最大安全切除的功效和安全性。
    2018年1月1日至2022年8月1日在乌卢达大学医学院神经外科因脑转移而接受AC的患者进行了回顾性分析。该研究包括2个患者组:普通AC(pAC)和NaFl引导的AC(NaFlg-AC)。与荧光强度相关的手术结果,切除程度,围手术期并发症,并对术后神经因素进行评估。
    pAC组包括16名患者(12名男性,4名女性),NaFlg-AC组由21人组成(13名男性,7名女性)。男性和女性的平均患者年龄分别为61.4岁(61.4±9.5岁)和60.4岁(60.6±12岁),分别。在pAC和NaFlg-AC组中,转移性病变的最常见起源是肺(n=12vs.分别为n=14)。NaFlg-AC组中85.7%的患者实现了总切除(GTR),而pAC组GTR率为68.7%。两组之间的GTR率没有显着差异(p=0.254)。NaFlg-AC组的平均切除时间明显缩短(45.95±7.00minvs.57.5±12.51分钟;p=0.002)。两组患者的Karnofsky表现状态(KPS)评分在随访6个月时与其术前基线评分相比均未达到统计学意义(p=0.374)。KPS在任何时间均未显示2组之间的显着差异。
    在AC中的荧光引导切除术用于感觉转移性肿瘤,电机,认知领域是可行的,安全,和方便的技术,显着提高GTR率和缩短手术时间相比,传统的白光手术没有荧光引导。它也不会增加术后并发症的发生率。随着AC和NaFl的结合使用,确保手术期间肿瘤边缘清晰可见,并实时控制患者的神经功能是可能的。
    UNASSIGNED: Awake craniotomy (AC) maximizes the resection of lesions in eloquent brain areas while preserving functionality. Tumor delineation with intraoperative use of sodium fluorescein (NaFl) facilitates total resection. When used with AC, it may allow for safe resection without increasing the risk of postoperative neurologic deficits. This study investigated the efficacy and safety of the combined use of NaFl and AC for maximum safe resection in patients with brain metastases.
    UNASSIGNED: Patients who underwent AC due to brain metastasis in the Department of Neurosurgery of Uludağ University\'s Faculty of Medicine between January 1, 2018 and August 1, 2022, were retrospectively analyzed. The study comprised 2 patient groups: plain AC (pAC) and NaFl-guided AC (NaFlg-AC). Surgical outcomes related to fluorescence intensity, degree of resection, perioperative complications, and postoperative neurological factors were evaluated.
    UNASSIGNED: The pAC group included 16 patients (12 males, 4 females), and the NaFlg-AC group comprised 21 (13 males, 7 females). The mean patient ages for males and females were 61.4 years (61.4 ± 9.5 years) and 60.4 years (60.6 ± 12 years), respectively. The most common origin of the metastatic lesion was the lung in both the pAC and NaFlg-AC groups (n = 12 vs. n = 14, respectively). Gross total resection (GTR) was achieved in 85.7% of the patients in the NaFlg-AC group, whereas the GTR rate was 68.7% in the pAC group. There was no significant difference in GTR rates between the 2 groups (p = 0.254). The mean duration of the resection time was significantly shorter in the NaFlg-AC group (45.95 ± 7.00 min vs. 57.5 ± 12.51 min; p = 0.002). The patients\' Karnofsky Performance Status (KPS) score did not reach statistical significance at 6-month follow-up in either group compared to their preoperative baseline scores (p = 0.374). KPS did not show a significant difference between the 2 groups at any time.
    UNASSIGNED: Fluorescence-guided resection in AC for metastatic tumors in sensory, motor, and cognitive areas is a feasible, safe, and convenient technique that significantly increases GTR rates and shortens operative time compared to conventional white light surgery without fluorescence guidance. It also does not increase the incidence of postoperative complications. With the combined use of AC and NaFl, ensuring clear and visible tumor margins during surgery and controlling patients\' neurological function in real-time are possible.
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  • 文章类型: Journal Article
    目的:雄辩和深部脑区的重要功能需要对位于这些区域的肿瘤进行精确治疗。荧光素引导手术(FGS)已广泛用于高级别神经胶质瘤(HGG)切除。然而,利用该技术切除位于雄辩和深层区域的脑肿瘤的安全性和有效性仍不确定.这项研究旨在评估在这些具有挑战性的肿瘤中使用荧光素切除HGs的安全性和程度,并探讨其对患者生存的影响。
    方法:对在2020年1月至2023年6月期间接受手术的67例雄辩性或深层HGG患者的临床和放射学数据进行了回顾性分析。Lacroix功能定位等级用于确定肿瘤的雄辩性。荧光引导手术组(FGS,n=32)和常规白光显微镜手术组(非FGS,n=35)包括对切除程度(EOR)的评估,总切除率(GTR,100%)和近乎完全切除(NTR,99至98%),神经肿瘤学术后神经系统评估(NANO)评分,总生存期(OS),和无进展生存期(PFS),评估荧光素引导技术在这些特定位置的肿瘤切除中的安全性和有效性。
    结果:人口统计基线,病变位置,两组间病理差异无统计学意义。FGS组的GTR高于非FGS组(84.4%vs.60.0%,OR3.60,95%CI1.18-10.28,p<0.05)。FGS组的GTR+NTR(EOR≥98%)也高于非FGS组(93.8%vs.65.7%,OR7.83,95%CI1.86-36.85,p<0.01)。FGS组中87.0%的雄辩性肿瘤(LacroixIII级)达到GTR+NTR,对照组52.2%(OR6.11,95%CI1.50-22.78,p<0.05)。对于深层肿瘤,两组GTR+NTR的发生率分别为91.7%和53.3%,分别为(OR9.62,95%CI1.05-116.50,p<0.05)。两组患者术前NANO评分差异无统计学意义。FGS组术后NANO评分明显低于非FGS组(2.56±1.29vs.3.43±1.63,p<0.05)。FGS组的中位OS比非FGS组长4.2个月,尽管没有统计学差异(18.2个月与14.0个月,HR0.63,95%CI0.36-1.11,p=0.112),而FGS患者的PSF明显长于非FGS组(11.2个月vs.7.7个月,HR0.59,95%CI0.35-0.99,p<0.05)。
    结论:荧光素钠引导手术治疗脑区和深部高级别胶质瘤可以实现更广泛的切除,同时保留神经功能并提高患者生存率。
    OBJECTIVE: The vital function of eloquent and deep brain areas necessitates precise treatment for tumors located in these regions. Fluorescein-guided surgery (FGS) has been widely used for high-grade gliomas (HGGs) resection. Nevertheless, the safety and efficacy of utilizing this technique for resecting brain tumors located in eloquent and deep-seated areas remain uncertain. This study aims to assess the safety and extent of resection of HGGs in these challenging tumors with fluorescein and explore its impact on patient survival.
    METHODS: A retrospective analysis was conducted on the clinical and radiological data of 67 consecutive patients with eloquent or deep-seated HGGs who underwent surgery between January 2020 and June 2023. Lacroix functional location grade was used to determine the eloquence of the tumors. The comparison between the fluorescence-guided surgery group (FGS, n = 32) and the conventional white-light microscopic surgery group (non-FGS, n = 35) included assessments of extent of resection (EOR), rates of gross total resection (GTR, 100%) and near-total resection (NTR, 99 to 98%), postoperative Neurologic Assessment in Neuro-Oncology (NANO) scores, overall survival (OS), and progression-free survival (PFS), to evaluate the safety and efficacy of fluorescein-guided technology in tumor resection at these specific locations.
    RESULTS: Baseline of demographics, lesion location, and pathology showed no significant difference between the two groups. GTR of the FGS group was higher than the non-FGS group (84.4% vs. 60.0%, OR 3.60, 95% CI 1.18-10.28, p < 0.05). The FGS group also showed higher GTR + NTR (EOR ≥ 98%) than the non-FGS group (93.8% vs. 65.7%, OR 7.83, 95% CI 1.86-36.85, p < 0.01). 87.0% of eloquent tumors (Lacroix grade III) in the FGS group achieved GTR + NTR, compared to 52.2% of control group (OR 6.11, 95% CI 1.50-22.78, p < 0.05). For deep-seated tumors, the rate of GTR + NTR in the two groups were 91.7% and 53.3%, respectively (OR 9.62, 95% CI 1.05-116.50, p < 0.05). No significant difference of the preoperative NANO score of the two groups was found. The postoperative NANO score of the FGS group was significantly lower than the non-FGS group (2.56 ± 1.29 vs. 3.43 ± 1.63, p < 0.05). Median OS of the FGS group was 4.2 months longer than the non-FGS group despite no statistical difference (18.2 months vs. 14.0 months, HR 0.63, 95% CI 0.36-1.11, p = 0.112), while PSF was found significantly longer in FGS patients than those of the non-FGS group (11.2 months vs. 7.7 months, HR 0.59, 95% CI 0.35-0.99, p < 0.05).
    CONCLUSIONS: Sodium fluorescein-guided surgery for high-grade gliomas in eloquent and deep-seated brain regions enables more extensive resection while preserving neurologic function and improve patient survival.
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  • 文章类型: Journal Article
    由平面偏振光激发荧光团引起的荧光具有不同的偏振,这取决于含荧光团试剂的大小及其旋转速率。基于这种效应,已经实施了许多分析系统,其中包含在样品中并且用荧光团(通常是荧光素)标记的分析物竞争结合抗体。用适体代替这种测定中的抗体,低成本和稳定的寡核苷酸受体,是复杂的,因为将荧光团结合到它们会导致发射极化的变化不太明显。这项工作提出并表征了反应介质的化合物,这些化合物可以改善分析物的结合并降低适体-荧光团复合物的迁移率,提供较高的分析信号和较低的检测限。本研究对黄曲霉毒素B1(AFB1)、一种无处不在的有毒物质,污染植物来源的食物。比较了8种具有相同结合位点和不同区域稳定其结构的AFB1特异性适体的亲和力,基于此选择具有38个核苷酸长度的适体。与寡核苷酸可逆相互作用的聚合物,如聚-L-赖氨酸和聚乙二醇,进行了测试。发现它们提供了所需的发射光的去极化减少以及高浓度的镁阳离子。在选定的最佳培养基中,AFB1检测达到1ng/mL的极限,比通常用于抗AFB1适体的tris缓冲液低12倍。测定时间为30分钟。此方法适用于根据AFB1污染的最大允许水平控制杏仁样品。所提出的方法可以应用于改进其他基于适体的分析系统。
    Fluorescence induced by the excitation of a fluorophore with plane-polarized light has a different polarization depending on the size of the fluorophore-containing reagent and the rate of its rotation. Based on this effect, many analytical systems have been implemented in which an analyte contained in a sample and labeled with a fluorophore (usually fluorescein) competes to bind to antibodies. Replacing antibodies in such assays with aptamers, low-cost and stable oligonucleotide receptors, is complicated because binding a fluorophore to them causes a less significant change in the polarization of emissions. This work proposes and characterizes the compounds of the reaction medium that improve analyte binding and reduce the mobility of the aptamer-fluorophore complex, providing a higher analytical signal and a lower detection limit. This study was conducted on aflatoxin B1 (AFB1), a ubiquitous toxicant contaminating foods of plant origins. Eight aptamers specific to AFB1 with the same binding site and different regions stabilizing their structures were compared for affinity, based on which the aptamer with 38 nucleotides in length was selected. The polymers that interact reversibly with oligonucleotides, such as poly-L-lysine and polyethylene glycol, were tested. It was found that they provide the desired reduction in the depolarization of emitted light as well as high concentrations of magnesium cations. In the selected optimal medium, AFB1 detection reached a limit of 1 ng/mL, which was 12 times lower than in the tris buffer commonly used for anti-AFB1 aptamers. The assay time was 30 min. This method is suitable for controlling almond samples according to the maximum permissible levels of their contamination by AFB1. The proposed approach could be applied to improve other aptamer-based analytical systems.
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  • 文章类型: Journal Article
    外泌体的分析为肿瘤的快速和非侵入性筛查提供了重要信息。然而,到目前为止,外泌体的灵敏和方便的检测在技术上仍然具有挑战性。在这里,基于FITC的光刺激氧化酶模拟活性,构建了一种比色传感器,用于检测卵巢癌(OC)外泌体。aptasensor包含EpCAM适体以捕获OC外来体。使用胆固醇和荧光素(FITC)修饰DNA的任一端(DNA锚)。DNA锚可以通过胆固醇和脂质膜之间的疏水反应与外泌体结合。FITC氧化3,3\',5,5'-四甲基联苯胺(TMB)在温和条件下以时间可控的方式在365nmLED光源下,导致溶液从无色变成蓝色,相应的UV-vis吸光度增加。基于这个原则,用肉眼观察外泌体的颜色变化进行定性分析。并行,也使用UV-vis分光光度法检测外泌体浓度。线性范围为2×105至100×105个颗粒/mL,检出限为1.77×105个颗粒/mL。开发的aptasensor还表现出良好的选择性,可以区分OC细胞和正常细胞的外泌体。此外,受试者工作特征(ROC)曲线表明,使用外泌体作为生物标志物,可以区分OC患者和健康供体(HDs).我们的技术可以扩展基于DNA的检测方法启用的OC诊断工具的应用。
    Analysis of exosomes provides important information for rapid and non-invasive screening of tumors. However, sensitive and convenient detection of exosomes remains technically challenging to date. Herein, a colorimetric aptasensor based on the light-stimulated oxidase-mimicking activity of FITC was constructed for detecting ovarian cancer (OC) exosomes. The aptasensor contained an EpCAM aptamer to capture OC exosomes. Cholesterol and fluorescein (FITC) were used to modify either end of the DNA (DNA anchor). The DNA anchor could combine with exosomes through a hydrophobic reaction between cholesterol and the lipid membrane. FITC oxidized 3,3\',5,5\'-tetramethylbenzidine (TMB) under a 365 nm LED light source in a temporally controllable manner under mild conditions, causing the solution to change from colorless to blue, and the corresponding UV-vis absorbance increased. Based on this principle, the exosomes were qualitatively analyzed by observing the color change with the naked eye. In parallel, the exosome concentration was also detected using UV-vis spectrophotometry. The linear range was from 2 × 105 to 100 × 105 particles per mL with a limit of detection of 1.77 × 105 particles per mL. The developed aptasensor also exhibited favorable selectivity and could discriminate the exosomes from OC cells and normal cells. Besides, the receiver operating characteristic (ROC) curve demonstrates that it is possible to distinguish between patients with OC and healthy donors (HDs) using exosomes as the biomarker. Our technology may expand the applications of DNA-based detection method-enabled OC diagnostic tools.
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  • 文章类型: Journal Article
    据报道,无定形二氧化硅颗粒(ASP)具有生物活性,并成为生物陶瓷的关注焦点。然而,它们与活生物体中蛋白质的相互作用仍有待理解,需要进行研究,以实现更广泛的应用。我们的研究小组发现,含氯(Cl)的ASP可用于蛋白质固定。光功能染料(荧光素(FS-),以羧基和氨基为主要官能团的亚甲基蓝(MB))通过机械化学方法作为模型分子固定在含Cl的ASP上,并使用其光谱性质研究和讨论有机/无机界面键合状态。在FS-,分子中羧基的氧原子通过氢键与ASPs表面上的硅烷醇基团固定,表明作为单体状态存在用于固定的最佳Cl含量。在MB+的情况下,随着ASP中Cl浓度的增加,通过ASPs中的Cl与末端二甲基氨基之间的静电相互作用进行固定,并且MB杂环的N原子与颗粒硅烷醇基之间的氢键增强。这些结果主要表明,蛋白质吸附系统通过蛋白质的羧基与颗粒上的硅烷醇基团之间的氢键键合以及蛋白质的氨基与解离的硅烷醇基团和颗粒上所含的Cl之间的静电相互作用而发生。因此,使用染料作为探针的光谱表征有望预测蛋白质与无定形二氧化硅颗粒的相互作用。
    Amorphous silica particles (ASPs) have been reported to exhibit bioactive properties and are becoming the focus of attention as bioceramics. However, their interactions with proteins in living organisms remain to be understood and need to be investigated in order to achieve wider applications. Our research group found that chlorine (Cl)-containing ASPs are useful for protein immobilization. Photofunctional dyes (fluorescein (FS-), methylene blue (MB+)) that have the carboxy and amino groups as the main functional groups were immobilized on the Cl-containing ASPs via the mechanochemical method as the model molecule and their spectral properties were used to investigate and discuss the organic/inorganic interfacial bonding states. In FS-, the oxygen atoms of the carboxy groups in the molecule were immobilized by the hydrogen bonds with the silanol groups on the ASPs surfaces, indicating that there is an optimum Cl content for the immobilization as the monomer state. In the case of MB+, as the Cl concentration in the ASPs increases, the immobilization via the electrostatic interactions between the Cl in the ASPs and the terminal dimethylamino group, and the hydrogen bonding between the N atoms of the MB+ hetero ring and the particle silanol group were enhanced. These results mainly suggest that the protein adsorption system occurs through the hydrogen bonding between the carboxy groups of the protein and the silanol groups on the particles and via electrostatic interactions between the amino groups of the protein and the dissociated silanol groups and the contained Cl at the particles. Thus, the spectral characterization using dyes as probes is expected to predict the protein interactions with the amorphous silica particles.
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  • 文章类型: Journal Article
    铁载体-抗生素缀合物的设计是克服阴性细菌耐药性的有希望的策略。然而,越来越多的研究表明,只有那些作用于细胞壁或细胞膜的抗生素,当与铁载体结合时,才能繁殖它们的抗菌作用,而作用于细菌细胞质中靶标的抗生素与铁载体结合时,其抗菌作用并未显着增强。为了探究这种现象的原因,我们使用3-羟基吡啶-4(1H)-酮作为铁载体,并用5-羧基荧光素(5-FAM)或孔雀石绿(MG)货物代替抗生素货物,合成了几种偶联探针。通过监测细菌中FAM缀合物20的荧光强度变化,证实了缀合物穿过革兰氏阴性病原体的外膜的易位。Further,使用荧光原激活蛋白(FAP)/MG系统表明,3-羟基吡啶-4(1H)-one-MG缀合物26最终主要分布在周质中,而不是转移到大肠杆菌和铜绿假单胞菌PAO1的胞质溶胶中。其他机理研究表明,缀合物的摄取涉及铁载体依赖性铁转运途径和3-羟基吡啶-4(1H)-酮铁载体受体依赖性机制。同时,我们证明了3-羟基吡啶-4(1H)-酮与荧光素5-FAM的缀合可以减少缀合物通过被动扩散穿过哺乳动物Vero细胞膜层的可能性,以及与三-3-羟基吡啶-4(1H)-酮相比,单-3-羟基吡啶-4(1H)-酮作为缀合物设计中的递送载体的优势。总的来说,这项工作揭示了3-羟基吡啶-4(1H)-酮作为铁载体将货物运送到革兰氏阴性细菌中的定位规则。为后续铁载体-抗生素偶联物的设计提供了理论依据,特别是基于3-羟基吡啶-4(1H)-酮作为铁载体。
    The design of siderophore-antibiotic conjugates is a promising strategy to overcome drug resistance in negative bacteria. However, accumulating studies have shown that only those antibiotics acting on the cell wall or cell membrane multiply their antibacterial effects when coupled with siderophores, while antibiotics acting on targets in the cytoplasm of bacteria do not show an obvious enhancement of their antibacterial effects when coupled with siderophores. To explore the causes of this phenomenon, we synthesized several conjugate probes using 3-hydroxypyridin-4(1H)-ones as siderophores and replacing the antibiotic cargo with 5-carboxyfluorescein (5-FAM) or malachite green (MG) cargo. By monitoring changes in the fluorescence intensity of FAM conjugate 20 in bacteria, the translocation of the conjugate across the outer membranes of Gram-negative pathogens was confirmed. Further, the use of the fluorogen activating protein(FAP)/MG system revealed that 3-hydroxypyridin-4(1H)-one-MG conjugate 26 was ultimately distributed mainly in the periplasm rather than being translocated into the cytosol of Escherichia coli and Pseudomonas aeruginosa PAO1. Additional mechanistic studies suggested that the uptake of the conjugate involved the siderophore-dependent iron transport pathway and the 3-hydroxypyridin-4(1H)-ones siderophore receptor-dependent mechanism. Meanwhile, we demonstrated that the conjugation of 3-hydroxypyridin-4(1H)-ones to the fluorescein 5-FAM can reduce the possibility of the conjugates crossing the membrane layers of mammalian Vero cells by passive diffusion, and the advantages of the mono-3-hydroxypyridin-4(1H)-ones as a delivery vehicle in the design of conjugates compared to the tri-3-hydroxypyridin-4(1H)-ones. Overall, this work reveals the localization rules of 3-hydroxypyridin-4(1H)-ones as siderophores to deliver the cargo into Gram-negative bacteria. It provides a theoretical basis for the subsequent design of siderophore-antibiotic conjugates, especially based on 3-hydroxypyridin-4(1H)-ones as siderophores.
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