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Fabrication of a 3D in vitro model that mimics the artery takes an important role in understanding pathological cell behaviors and mechanisms of vascular diseases by proposing an advanced model that can recapitulate a native vessel condition in a controlled manner. Because a model geometry and the structure of cells are significant for the recapitulation of the hemodynamics of arterial and cell functions, it is necessary to mimic geometries and to induce the proper morphology and orientation of the cells when fabricating a model. In this study, smooth muscle cells (SMCs) and endothelial cells (ECs), which were the main elements in the arterial wall, were cocultured in a multichannel device connected with polydimethylsiloxane (PDMS) fluidic chamber modules to parallelly fabricate a pefusable 3D in vitro human artery-mimicking multichannel system. In the coculture model, a circular PDMS channel with a wrinkled-surface guided directionality and contractile morphology to SMCs, and media perfusion induced directionality to a confluent EC layer as in vivo. Protein markers of cells and synthesized extracellular matrices were demonstrated. Because multichannels were connected to a microfluidic module in a device, it was possible to easily control the microenvironmental conditions and to fabricate coculture models in parallel with a single flow system. Coculture models that can be tuned in designs such as diameter, wall shear stress, and geometry of artery disease were constructed by 3D-printed molds to recapitulate various cellular microenvironments and to model vessels effectively. Finally, the effect of wall shear stress on cells was compared using a device with four different degrees of stenosis channels and investigated in parallel.

We present a multiplexed microfluidic immunohistochemistry (IHC) technology that enables high-throughput analysis of tissue microarrays (TMAs) using the patterns of biomarker barcodes, which consist of a series of expressed linear patterns of specific biomarkers. A multichannel poly(dimethylsiloxane) microfluidic device was reversibly assembled by the pressure of simple equipment for multiplexed IHC on each core of TMA or cell microarray (CMA) section slides. By injecting primary antibodies from different biomarkers independently into each channel, multiplexed immunostaining can be performed on each core of TMA. We confirmed the equal immunostaining quality regardless of the channel orders and core positions in the slide. Four different biomarkers (ER, PR, HER2, and Ki67) were used for the demonstration of distinctive expression patterns on CMAs which consist of six different breast cancer cell lines, and it was confirmed that these bar-like signals could be a biomarker barcode for the TMA core. A biomarker barcode of breast cancer patient-derived TMA was quickly scanned by a slide scanner and compared to the conventional method for breast cancer diagnosis. This “barcode-IHC” concept, which has been verified by performing multiplexed microfluidic IHC on CMA and TMA samples, provides high reproducibility and the potential of high-throughput screening with molecular diagnostic capability.

We investigated the relations among theory of mind (ToM), mental state talk, and discourse comprehension. Specifically, we examined the frequency of mental state talk in children’s oral recall of narrative texts and informational texts as well as relations among ToM, mental state talk (inclusion of mental state words in the recall of narrative and informational texts), and narrative and informational text comprehension. Results from children in Grade 4 (N = 132; Mage = 10.39 years) revealed that a greater number of mental state talk instances appeared in children’s recall of narrative texts than in their recall of informational texts, but the mean number also differed across texts within a genre. ToM skill predicted the extent of mental state talk in narrative texts and informational texts, and the relation was stronger for narrative texts than for informational texts, after accounting for vocabulary, grammatical knowledge, working memory, and attentional control. Mental state talk in narrative texts was extremely strongly related to narrative comprehension, whereas mental state talk in informational texts was weakly related to informational text comprehension. Results suggest that ToM skill relates to mental state talk in the recall of texts, and both ToM and mental state talk play greater roles in comprehension of narrative texts than in comprehension of informational texts.

Surface electromyogram (sEMG) is often used by to objectively measure muscular activity during rehabilitation exercises. sEMG is accurate, but it is unsuitable for uses outside the clinic, and patients can benefit from an unobtrusive device which can be readily used to ubiquitously measure abdominal muscle activation. In this study, we present a pressure sensor system which can be latched onto a belt to measure abdominal muscle activation. sEMG and pressure sensor output were measured in 15 healthy young males during isometric trunk flexion exercise (public trials registration number, KCT0002351), and the results were highly correlated (median R > 0.939). As initial contact force can change the pressure sensor sensitivity, the experiment was performed at two different levels of belt tightness, but the correlations did not significantly improve after tightening the belt, suggesting that the system can be used to ubiquitously and unobtrusively monitor abdominal muscle activity with minimal discomfort.

Considering rarity of circulating tumor cells (CTCs) in human blood, the development of highly sensitive detection techniques for cancer cells is crucial for prediction, diagnosis, and prognosis of cancers. In this study, we propose an advanced cellular detection method by combining a biobarcode assay and microcapillary electrophoresis (μCE) technology. While the DNA biobarcode assay can provide ultrasensitive and multiplex detection platforms, the μCE chip can analyze barcode DNAs with high speed and accuracy according to the DNA size. We designed the barcode DNA size as 20 bp for indicating the expression of epithelial cell adhesion molecules (EpCAM) biomarkers and 30 bp for assigning CDX2 expression which is specific for colorectal cancer cells with addition to two bracket ladders (15 and 45 bp). Using MCF-7 (breast cancer) and SW620 (colorectal cancer) as models, we conducted a biobarcode assay and analyzed the resultant biobarcode DNA on the μCE chip. We could detect the 20 bp CE peak in the electropherogram even with ten MCF-7 and SW620 cells in a volume of 200 μL, thereby demonstrating the highly sensitive detection of cancer cells. We furthermore identified the type of colorectal cancer by observing two positive peaks (20 bp for EpCAM and 30 bp for CDX2) in the μCE analysis.

Early diagnosis of biological agents is of paramount importance to prevent the casualties and fatal disease in human during bioterrorism or biological warfare. In this study, we reported an efficient and sensitive multiplex biological agent detection method based on the DNA biobarcode assay and the micro-capillary electrophoresis (μCE) technology. Monoplex as well as multiplex pathogen identification was performed using five targets including Bacillus anthracis , Francisella tularensis , Yersinia pestis , Vaccinia virus and Botulinum toxin A. Through the DNA biobarcode assay process, the magnetic microparticle–pathogen–polystyrene microbead complexes were formed, and the FAM labeled single stranded barcode DNA could be released from the complexes upon denaturation. Different lengths of a barcode DNA were designed to designate each pathogen, so that the specific peak elution time in the capillary electrophoresis on a chip allows us to distinguish the target with high accuracy within 3 min. We improved the assignment accuracy of the peak in the electropherogram by adding two bracket ladders. Owing to the abundant amount of barcode DNAs, the presence of B. anthracis , F. tularensis , Y. pestis , Vaccinia virus was confirmed with a limit of detection of 50 CFU/mL, while Botulinum toxin A was analyzed even at a concentration of 12.5 ag/mL. Multiple pathogen detection was also successfully conducted in a phosphate buffered saline (PBS) as well as a serum medium with background of other pathogens. Thus, our analytical platform based on the biobarcode assay and on-chip CE analysis provides rapid, sensitive, multiplex, and accurate biological agent identification.