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181.
182.
Karuntarat Teeravirote Sukanya Luang Sakda Waraasawapati Patcharee Boonsiri Chaisiri Wongkham Sopit Wongkham Atit Silsirivanit 《Molecules (Basel, Switzerland)》2021,26(9)
Plant lectins are widely used in medical glycosciences and glycotechnology. Many lectin-based techniques have been applied for the detection of disease-associated glycans and glycoconjugates. In this study, Butea monosperma agglutinin (BMA), a lectin purified from seeds of the medicinal plant Butea monosperma, was used for the detection of cholangiocarcinoma (CCA)-associated glycans. Expression of BMA-binding N-acetyl galactosamine/galactose (GalNAc/Gal)-associated glycan (BMAG) in CCA tissues was determined using BMA lectin histochemistry; the results showed that BMAG was undetectable in normal bile ducts and drastically increased in preneoplastic bile ducts and CCA. The study in hamsters showed that an increase of BMAG was associated with carcinogenesis of CCA. Using an in-house double BMA sandwich enzyme-linked lectin assay, BMAG was highly detected in the sera of CCA patients. The level of serum BMAG in CCA patients (N = 83) was significantly higher than non-CCA controls (N = 287) and it was applicable for diagnosis of CCA with 55.4% sensitivity, 81.9% specificity, and 76.0% accuracy. A high level of serum BMAG (≥82.5 AU/mL) was associated with unfavorable survival of CCA patients; this information suggested the potential of serum BMAG as a poor prognostic indicator of CCA. In summary, BMAG was aberrantly expressed in preneoplastic bile ducts and CCA, it was also highly detected in patient serum which potentially used as a marker for diagnosis and prognostic prediction of CCA. 相似文献
183.
Xiaoyun Wei Keke Chen Zixiang Wang Ben Huang Yuan Wang Mingxia Yu Wei Liu Shi‐shang Guo Xing‐Zhong Zhao 《Particle & Particle Systems Characterization》2019,36(6)
Detection of rare circulating tumor cells (CTCs) from patients has an important effect on clinical cancer diagnosis and prognosis. Here, an integrated microfluidic chip for efficient isolation and downstream analysis of CTCs is developed. This new designed platform, gelatin nanoparticle (GNP) integrated microchip, combines a series of curved herringbone structures, which generate enhanced interactions between CTCs and the immunomodified channel surface, with multifunctional GNP based nanostructured surface, which not only provide more binding sites for antibodies and targets and avoid nonspecific absorption of blood cells due to its electronegative surface charge, but also enable viable cell release under a mild enzymatic treatment. The chip allows cell isolation with ≈85% capture yield and ≈90% release efficiency using spiked cell samples. Results demonstrate that the released cancer cells maintain good viability and proliferation ability. Furthermore, the microchip is successfully applied to capture noninvasive release and genetically analyze CTCs from clinical cancer patients. The proposed platform may provide a potential in clinics. 相似文献
184.
185.
Inside Back Cover: Selective Targeting of Tumor and Stromal Cells By a Nanocarrier System Displaying Lipidated Cathepsin B Inhibitor (Angew. Chem. Int. Ed. 38/2014) 下载免费PDF全文
186.
Circulating tumor cells (CTCs) present in the bloodstream are strongly linked to the invasive behavior of cancer; therefore, their detection holds great significance for monitoring disease progression. Currently available CTC isolation tools are often based on tumor-specific antigen or cell size approaches. However, these techniques are limited due to the lack of a unique and universal marker for CTCs, and the overlapping size between CTCs and regular blood cells. Dielectrophoresis (DEP), governed by the intrinsic dielectric properties of the particles, is a promising marker-free, accurate, fast, and low-cost technique that enables the isolation of CTCs from blood cells. This study presents a continuous flow, antibody-free DEP-based microfluidic device to concentrate MCF7 breast cancer cells, a well-established CTC model, in the presence of leukocytes extracted from human blood samples. The enrichment strategy was determined according to the DEP responses of the corresponding cells, obtained in our previously reported DEP spectrum study. It was based on the positive-DEP integrated with hydrodynamic focusing under continuous flow. In the proposed device, the parylene microchannel with two inlets and outlets was built on top of rectangular and equally spaced isolated planar electrodes rotated certain degree relative to the main flow (13°). The recovery of MCF7 cells mixed with leukocytes was 74%–98% at a frequency of 1 MHz and a magnitude of 10–12 Vpp. Overall, the results revealed that the presented system successfully concentrates MCF7 cancer cells from leukocytes, ultimately verifying our DEP spectrum study, in which the enrichment frequency and separation strategy of the microfluidic system were determined. 相似文献
187.
癌症的发生和发展伴随着一系列复杂的分子病理学变化, 具有极大的个体差异性. 因此, 实现肿瘤的精准诊断, 尤其是分子病理学的诊断尤为重要. 在临床检测中, 传统影像学检查可以反映肿瘤的位置和解剖学结构, 却难以对其分子病理做出判定; 而病理活检虽然可以获取肿瘤的分子学特征, 但需通过创伤性手段获取样本, 且具有时空局限性. 相比之下, 借助于特异性探针成像的肿瘤分子影像学, 直接以肿瘤病理分子标志物作为成像对比度的来源, 旨在从分子层面对肿瘤进展中的病理学特征进行在体定量化分析, 在肿瘤的精准诊断中具备独特的优势. 近年来, 纳米材料由于优越的理化性质, 已经成为构建高灵敏肿瘤分子影像探针的重要信号载体之一. 基于此, 本综述从基本的纳米靶向探针, 到光、磁学智能响应型纳米探针, 系统总结归纳了基于纳米材料的分子影像技术对肿瘤病理在体可视化的研究进展, 并对未来临床环境中实施该纳米探针技术进行了展望. 相似文献
188.
本研究探讨腹部彩超联合糖类抗原125(CA125)诊断卵巢浆液性肿瘤的价值。选取卵巢浆液性肿瘤患者80例,其中卵巢浆液性囊腺瘤患者23例,浆液性交界性肿瘤患者30例,浆液性癌患者27例,比较各组超声特征及血清CA125差异。浆液性交界性肿瘤、浆液性癌患者囊实性回声、有血流分布、腹水比例明显高于卵巢浆液性囊腺瘤患者(P<0.05),形态规则、边界清晰比例明显低于卵巢浆液性囊腺瘤患者(P<0.05);浆液性癌患者血清CA125为(301.45±104.42)U/mL,明显高于浆液性交界性肿瘤和卵巢浆液性囊腺瘤患者(P<0.05);浆液性交界性肿瘤患者血清CA125为(210.10±98.28)U/mL,明显高于卵巢浆液性囊腺瘤患者(P<0.05);超声联合血清CA125诊断浆液性癌的特异性、准确率和阳性预测值分别为90.57%、87.50%和81.48%,明显高于超声检查(P<0.05)。腹部彩超联合CA125鉴别诊断卵巢浆液性肿瘤有较好的价值。 相似文献
189.
Qualitative analysis of a time‐delayed free boundary problem for tumor growth under the action of external inhibitors 下载免费PDF全文
In this paper, a time‐delayed free boundary problem for tumor growth under the action of external inhibitors is studied. It is assumed that the process of proliferation is delayed compared with apoptosis. By Lp theory of parabolic equations, the Banach fixed point theorem and the continuation theorem, the existence and uniqueness of a global solution is proved. The asymptotic behavior of the solution is also studied. The proof uses the comparison principle and the iteration method. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
190.
Review: Aptamers in microfluidic chips 总被引:1,自引:0,他引:1
This review, covering reports published from 2002 to August 2010, shows how aptamers have made significant contributions in the improvements of microfluidic chips for affinity extraction, separations and detections. Furthermore, microfluidic chip methods for studying aptamer-target interactions and performing aptamer selections have also been summarized. Accordingly, research vacancies and future development trends in these areas are discussed. 相似文献