Analysis of anti-angiogenic mechanism of HangAmDan-B (HAD-B), a Korean traditional medicine, using antibody microarray chip

방지영,김응윤,심태경,유화승,이연월,김용수,조종관,최용진,정현자,강인철 한국바이오칩학회 2010 BioChip Journal Vol.4 No.4

The inhibitory effects of the water extract of HangAmDan-B(WEHAD-B), which is a crude extract of eight Korean medicinal animals and plants on bFGF-induced neovascularization were investigated. WEHAD-B significantly prevented bFGF-induced HUVE cell proliferation, adhesion, migration, and capillary-like tubular network formation. Half-maximal inhibition of proliferation on the endothelial cells by WEHAD-B was observed at a concentration of approximately 250 μg/mL. Our antibody microarray-based ProteoChip data showed that WEHAD-B increased the expression of STAT1 and Rb2, which are involved in cell growth, apoptosis, and controlling the cell cycle in bFGF-induced HUVECs. These results indicate that the inhibition of bFGF-induced angiogenesis by WEHAD-B may be due to upregulation of cell signaling proteins, STAT1 and Rb2. The blood vessel formation in a chick chorioallantoic membrane (CAM) treated with WEHAD-B was markedly reduced in length compared with a PBS-treated control group. Taken together, these data suggest that antibody-arrayed ProteoChip technology may be an useful tool for determining molecular mechanism of natural products in biological samples.

Soft Lithography for Microfluidics: a Review

김필남,권건우,박민철,이성훈,김선민,서갑양 한국바이오칩학회 2008 BioChip Journal Vol.2 No.1

Soft lithography has provided a low-expertise route toward micro/nanofabrication and is playing an important role in microfluidics, ranging from simple channel abrication to the creation of micropatterns onto a surface or within a microfluidic channel. In this review, the materials, methods, and applications of soft lithography for microfluidics are briefly summarized with a particular emphasis on integrated microfluidic systems containing physical microstructures or a topographically patterned substrate. Relevant exemplary works based on the combination of various soft lithographic methods using microfluidics are introduced with some comments on their merits and weaknesses.

Understanding Confounding Effects of Blood Handling Strategies on RNA Quality and Transcriptomic Alteration Using RNA Sequencing

고은정,유소연,김승환,김승준,이은일,황승용 한국바이오칩학회 2021 BioChip Journal Vol.15 No.2

Whole blood is one of the most widely utilized human samples in biological research and is useful for analyzing the mechanisms of diverse bio-molecular phenomena. However, owing to its fluidic properties, whole blood is relatively unstable in the frozen state compared to other samples. Because RNA is structurally unstable, sample damage can severely affect RNA quality, thereby reducing its usability. This study aimed to assess the quality of RNA which was prepared from blood stored at different temperatures and times prior to freezing, as well as the effect of long-term freezing. The quality of the RNA derived from different blood samples was assessed by measuring the RNA integrity number (RIN) and RNA sequencing to identify differentially expressed genes (DEGs, |fold-change (FC)|> 1.5, p < 0.05, false discovery rate (FDR) < 0.05) between the differently prepared RNA samples. We found that improper sample handling critically influenced both RNA quality and gene expression patterns. By suggesting the consequences, this study emphasizes the importance of sample management to obtain reliable downstream application outcomes.

Development of an Improved Stationary Liquid-phase Lab-ona- chip for the Field Monitoring of Paralytic Shellfish Toxins

유은경,최석정 한국바이오칩학회 2017 BioChip Journal Vol.11 No.1

A stationary liquid-phase lab-on-a-chip (SLP-LOC), in which magnetic particles are used as a solid phase, has been previously reported as a novel platform for immunoassay methods. The SLP-LOC had a simple structure with two chambers connected by a narrow channel. The assay was performed by transporting the particles from one chamber to the next while the liquid phases were in a stationary state. However, each chamber was frequently contaminated by other chamber materials because of the small volume of the channel. Consequently, in this work, we have developed a three-chamber SLP-LOC (3C-LOC) featuring an additional chamber containing a buffered washing solution positioned between the existing two chambers and connected by channels. The dimensions of the 3C-LOC were optimized to fit into a standard spectrophotometer cuvette holder, allowing the direct measurement of absorbance. The 3C-LOC exhibited improved washing efficiency, reliability, and sensitivity in an assay of standard saxitoxin samples. Furthermore, the method was used to effectively determine whether paralytic shellfish toxin (PST) levels in shellfish samples exceeded regulatory limits. The results of this study indicate that the 3C-LOC could provide a simple and rapid method to monitor PSTs in the field.

Alteration of Gene Expression Profile by Melatonin in Endothelial Cells

손건우,박용식,김근동,양하나,박혜림 한국바이오칩학회 2014 BioChip Journal Vol.8 No.2

Melatonin is secreted by the pineal gland and gastrointestinal tract and plays a role in circadian rhythm synchronization. Melatonin is also reported to have various physiological effects on endothelial cells. Endothelial cells are responsible for physiologic homeostasis and maintaining blood vessel permeability in vivo. In this study, using gene expression profiling, we confirmed about 151 up-regulation and 1,023 downregulation expression genes, with an expression level difference of ¤1.5-fold, after exposure to 100 μM and 1 mM melatonin concentrations in endothelial cells. The genes were classified into 16 functional groups based on their functions, including cell adhesion, immune response, lipid metabolism, and response to stress. We analyzed the gene expression profiling data of melatonin- treated human umbilical vein endothelial cells(HUVECs), which indicated a broad spectrum of physiological functions, including anti-oxidative/anti-inflammatory effects and cell-to-cell junction maintenancerelated genes.

Prenatally Diagnosed TTN Mutation with Repeated Bilateral Club Foot by Whole Exome Sequencing

심소현,김지연,성세라,박지은,신윤정,심성한,차동현 한국바이오칩학회 2017 BioChip Journal Vol.11 No.3

With significant advances in genomic technologies over recent years, Next-generation sequencing (NGS) has become an important tool not only for gene discovery and research but also for clinical genetic diagnosis of rare disorders and single-gene-disorder analysis. Many hundreds of single-gene disorders have been described that can manifest prenatally and will comprise a large portion of undiagnosed, chromosomally normal cases but underlying cause of the abnormality still remains unknown for the large majority of cases with an abnormal ultrasound. However, there has been little experience and study in using trio whole exome sequencing (WES) for prenatal diagnosis. In this report the NGS method was applied for the prenatal genetic diagnosis of unidentified life-threatening phenotype in one family and confirmed the pattern of inheritance of titinopathy as well as two novel TTNgene variations. The report presented in these pages offers a unique and valuable perspective on relevance and feasibility of NGS in prenatal diagnosis field.

Sensitivity of Quartz Crystal Microbalance Precipitation Sensor for Paraoxon-ethyl

김동경,김남수 한국바이오칩학회 2008 BioChip Journal Vol.2 No.3

A quartz crystal microbalance biosensor which measured the inhibition in enzyme activity by an organophosphorus pesticide, paraoxon-ethyl, was developed. When inhibitor concentration increased, sensor response gradually decreased owing to the inhibition of the immobilized biocatalyst. The relationship between inhibitor concentration and percent inhibition (%I) was Y (%I)=12.48X (log10 paraoxon-ethyl)+ 122.30 (r=0.8477) at the paraoxon-ethyl concentrations of 3.63×10-10-3.63×10-6 M. The %I values found for newly prepared acetylcholinesterase-immobilized sensor chips in the presence of 3.63×10-7 M paraoxon-ethyl were determined and the coefficient of variability for six measurements was found as 5.46%. A quartz crystal microbalance biosensor which measured the inhibition in enzyme activity by an organophosphorus pesticide, paraoxon-ethyl, was developed. When inhibitor concentration increased, sensor response gradually decreased owing to the inhibition of the immobilized biocatalyst. The relationship between inhibitor concentration and percent inhibition (%I) was Y (%I)=12.48X (log10 paraoxon-ethyl)+ 122.30 (r=0.8477) at the paraoxon-ethyl concentrations of 3.63×10-10-3.63×10-6 M. The %I values found for newly prepared acetylcholinesterase-immobilized sensor chips in the presence of 3.63×10-7 M paraoxon-ethyl were determined and the coefficient of variability for six measurements was found as 5.46%.

Controlled Production of Monodisperse Polycaprolactone Microspheres Using Flow-focusing Microfluidic Device

권혁진,김수현,김성욱,김주희,임근배 한국바이오칩학회 2017 BioChip Journal Vol.11 No.3

These days, biodegradable microsphere polymers have been attracting increasing interest as a cosmetic injectable filler. Particularly, polycaprolactone (PCL) microspheres are well known for their safety and long degradation time. However, these microspheres are usually produced by the conventional stirring method, which has an inherent drawback related to the size control of the microspheres; accurate size control is critical for the use of these microspheres as a filler. Here, we demonstrate the fabrication of monodisperse PCL microspheres in the size range of 26.6- 161 μm using a flow-focusing microfluidic device. The acquired coefficient of variation of the solidified microspheres is approximately 4.5%; thus, these microspheres meet the requirement of being monodisperse. The study results show the feasibility of manufacturing PCL microspheres using a microfluidic device, and these microspheres have better morphological characteristics, thereby reducing pain and infection after their injection into the skin. Furthermore, the specific target size of the solidified microspheres is met. Therefore, undesired outcomes after microsphere injection through the dermis, such as phagocytosis and inflammatory reactions, are less likely to occur.

Detection of Bacillus Cereus Using Bioluminescence Assay with Cell Wall-binding Domain Conjugated Magnetic Nanoparticles

박찬용,공민석,이주훈,SANGRYEOLRYU,박성수 한국바이오칩학회 2018 BioChip Journal Vol.12 No.4

Bacillus cereus can cause blood infections (i.e., sepsis). Its early detection is very important for treating patients. However, an antibody with high binding affinity to B. cereus is not currently available. Bacteriophage cell wall-binding domain (CBD) has strong and specific binding affinity to B. cereus. Here, we report the improvement in the sensitivity of an ATP bioluminescence assay for B. cereus detection using CBD-conjugated magnetic nanoparticles (CBDMNPs). The assay was able to detect as few as 10 colony forming units (CFU) per mL and 103 CFU per mL in buffer and blood. CBD-MNPs did not show any cross-reactivity with other microorganisms. These results demonstrate the feasibility of the ATP assay for the detection of B. cereus.

Recent Developments in 3D Printing of Droplet-Based Microfluidics

Adedamola D. Aladese,정헌호 한국바이오칩학회 2021 BioChip Journal Vol.15 No.4

The advent of microfluidics, especially with the integration of droplet-based systems, has led to significant innovations and outstanding applications in many fields. While this field of study has grown increasingly over the years, the conventional method of fabricating these devices has discouraged their large-scale production, making their commercialization almost impossible. This is because traditional methods of producing droplet-based microfluidics are mostly time-consuming and labor-intensive and involve multiple processes. The emergence of 3D printing has found its application in microfluidics, providing an avenue for ease of fabrication with the aim of overcoming the limitations of conventional methods. While previous studies focused on studying the role of 3D printing in microfluidics, no study has categorically focused on the application of additive manufacturing to droplet-based microfluidics. This paper reviews the various 3D printing techniques associated with droplet-based microfluidics. Furthermore, we identify the salient features, limitations, and material properties of each printing technique while providing certain projections about their future application.