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Cancers (Basel) ; 11(1)2019 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-30626171


Colorectal cancer (CRC) is the second most common cause of cancer-related death worldwide. Detecting and enumerating circulating tumor cells (CTCs) in patients with colorectal cancer emerged as an important prognostic tool which provides a direct estimate of metastatic potential. Improving the turnaround time and decreasing sample volume is critical for incorporating this liquid biopsy tool into routine practice. The objective of the current study was to validate the clinical feasibility of a self-assembled cell array (SACA) chip, a CTC counting platform with less than 4 h turnaround time, in patients with newly diagnosed colorectal cancers. In total, 179 patients with newly diagnosed colorectal cancers from a single institute were enrolled. Epithelial cell adhesion molecule positive (EpCAM(+)), cluster of differentiation 45 negative (CD45(-)) cells were isolated and enumerated from 2 mL of peripheral vein blood (PB) and inferior mesenteric vein blood (IMV) samples obtained during surgery. We found that the CTC count in PB but not IMV correlates with disease stages. Neoadjuvant chemotherapy did not lead to decreased CTC count in both types of blood samples. With cutoffs of four CTCs per 2 mL of blood, and serum carcinoembryonic antigen (CEA) level of 5 ng/mL, patients with non-metastatic disease were more likely to experience recurrence if they had high PB CTC count and high serum CEA concentration (odds ratio, 8.9). Our study demonstrates the feasibility of enumerating CTCs with a SACA chip in patients with colorectal cancer.

Micromachines (Basel) ; 9(5)2018 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-30424161


Transmembrane pressure across the glomerular filter barrier may underlie renal failure. However, studies of renal failure have been difficult owing to a lack of in vitro models to capture the transmembrane pressure in a controlled approach. Here we report a microfluidic platform of podocyte culture to investigate transmembrane pressure induced glomerular leakage. Podocytes, the glomerular epithelial cells essential for filtration function, were cultivated on a porous membrane supplied with transmembrane pressure ΔP. An anodic aluminum oxide membrane with collagen coating was used as the porous membrane, and the filtration function was evaluated using dextrans of different sizes. The results show that dextran in 20 kDa and 70 kDa can penetrate the podocyte membrane, whereas dextran in 500 kDa was blocked until ΔP ≥ 60 mmHg, which resembles the filtration function when ΔP was in the range of a healthy kidney (ΔP < 60 mmHg) as well as the hypertension-induced glomerular leakage (ΔP ≥ 60 mmHg). Additionally, analysis showed that synaptopodin and actin were also downregulated when ΔP > 30 mmHg, indicating that the dysfunction of renal filtration is correlated with the reduction of synaptopodin expression and disorganized actin cytoskeleton. Taking together, our microfluidic platform enables the investigation of transmembrane pressure in glomerular filter membrane, with potential implications for drug development in the future.

Sci Rep ; 8(1): 8503, 2018 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844339


A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.

Sci Rep ; 7(1): 11385, 2017 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-28900219


The conventional techniques to detect circulating tumour cells (CTCs) are lengthy and the use of centrifugal forces in this technique may cause cell mortality. As the number of CTCs in patients is quite low, the present study aims towards a gentler diagnostic procedure so as not to lose too many CTCs during the sample preparation process. Hence, a Three-Dimensional Microwell dialysis (3D-µDialysis) chip was designed in this study to perform gentle fluorescence-removal process by using dialysis-type flow processes without centrifuging. This leads to a minimum manual handling of CTCs obtained in our study without any contamination. In addition, a rapid staining process which necessitates only about half the time of conventional techniques (35 minutes instead of 90 minutes) is being illustrated by the employment of dialysis process (by dynamically removing water and waste at once) instead of only static diffusion (by statically removing only waste by diffusion). Staining efficiency of our technique is improved over conventional staining because of the flow rate in 3D-µDialysis staining. Moreover, the staining process has been validated with clinical whole blood samples from three TNM stage IV colon cancer patients. The current technique may be termed as "miniature rapid staining and dialysing system".

Dispositivos Lab-On-A-Chip , Microdiálise/métodos , Técnicas Analíticas Microfluídicas , Células Neoplásicas Circulantes/metabolismo , Células Neoplásicas Circulantes/patologia , Linhagem Celular Tumoral , Desenho de Equipamento , Humanos , Microdiálise/instrumentação , Coloração e Rotulagem
Sci Rep ; 6: 38171, 2016 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-27910861


Here, we discuss the development of a paper-based diagnostic device that is inexpensive, portable, easy-to-use, robust, and capable of running simultaneous tests to monitor a relevant inflammatory protein for clinical diagnoses i.e. C-reactive protein (CRP). In this study, we first attempted to make a paper-based diagnostic device via the wax printing method, a process that was used in previous studies. This device has two distinct advantages: 1) reduced manufacturing and assay costs and operation duration via using wax printing method to define hydrophobic boundaries (for fluidic devices or general POC devices); and, 2) the hydrophilicity of filter paper, which is used to purify and chromatographically correct interference caused by whole blood components with a tiny amount of blood sample (only 5 µL). Diagnosis was based on serum stain length retained inside the paper channels of our device. This is a balanced function between surface tension and chromatographic force following immune reactions (CRP assays) with a paper-embedded biomarker.

Glycobiology ; 22(5): 649-61, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22223757


Hepatoma-derived growth factor (HDGF) recognizes cell surface heparan sulfate to promote its internalization though binding to its N-terminal HATH (homologous to amino terminus of HDGF) domain. HDGF-related proteins (HRPs) all have the HATH domain in their N terminus. In this study, we report on the commonality of heparin binding in all HRPs with a broad range of heparin-binding affinity: HRP-4 is the strongest binder, and the lens epithelium-derived growth factor shows a relatively weak binding, with binding affinities (K(D)) showing 30-fold difference in magnitude. With the HDGF HATH domain used as a model, residue K19 was the most critical basic residue in molecular recognition and protein internalization, and with its proximal proline-tryptophan-tryptophan-proline motif, coordinated a conformational change when binding to the heparin fragment. Other basic residues, K21, K61, K70, K72 and R79, confer added contribution in binding that the total ionic interaction from these residues represents more than 70% of the binding energy. Because the positive-charged residues are conserved in all HRP HATH domains, heparin binding outside of cells might be of equal importance for all HRPs in mediating downstream signaling; however, distinct effects and/or distribution might be associated with the varying affinities to heparin.

Heparina/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Sequência de Aminoácidos , Animais , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Espectroscopia de Ressonância Magnética , Camundongos , Dados de Sequência Molecular , Ligação Proteica , Homologia de Sequência de Aminoácidos , Ressonância de Plasmônio de Superfície