Development of the Sensing Platform for Protein Tyrosine Kinase Activity.

A miniature tyrosinase-based electrochemical sensing platform for label-free detection of protein tyrosine kinase activity was developed in this study. The developed miniature sensing platform can detect the substrate peptides for tyrosine kinases, such as c-Src, Hck and Her2, in a low sample volume (1-2 μL). The developed sensing platform exhibited a high reproducibility for repetitive measurement with an RSD (relative standard deviation) of 6.

Development of flexible electrochemical impedance spectroscopy-based biosensing platform for rapid screening of SARS-CoV-2 inhibitors.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) enters the cells through the binding of its spike protein (S-protein) to the cell surface-expressing angiotensin-converting enzyme 2 (ACE2). Thus, inhibition of S-protein-ACE2 binding may impede SARS-CoV-2 cell entry and attenuate the progression of Coronavirus disease 2019 (COVID-19). In this study, an electrochemical impedance spectroscopy-based biosensing platform consisting of a recombinant ACE2-coated palladium nano-thin-film electrode as the core sensing element was fabricated for the screening of potential inhibitors against S-protein-ACE2 binding.

The Development of CMOS Amperometric Sensing Chip with a Novel 3-Dimensional TiN Nano-Electrode Array.

An electrochemical sensing chip with an 8 × 8 array of titanium nitride three-dimensional nano-electrodes (TiN 3D-NEA) was designed and fabricated via a standard integrated complementary metal oxide semiconductor process. Each nano-electrode in 3D-NEA exhibited a pole-like structure with a radius of 100 nm and a height of 35 nm. The numeric simulation showed that the nano-electrode with a radius of around 100 nm exhibited a more uniformly distributed electric field and a much higher electric field magnitude compared to that of the microelectrode.

Development of CpG-oligodeoxynucleotides for effective activation of rabbit TLR9 mediated immune responses.

CpG-oligodeoxynucleotides (CpG-ODN) are potent immune stimuli being developed for use as adjuvants in different species. Toll-like receptor 9 (TLR9) is the cellular receptor for CpG-ODN in mammalian cells. The CpG-ODN with 18-24 deoxynucleotides that are in current use for human and mouse cells, however, have low activity with rabbit TLR9.

A general strategy to achieve ultra-high gene transfection efficiency using lipid-nanoparticle composites.

Gene therapy provides a new hope for previously "incurable" diseases. Low gene transfection efficiency, however, is the bottle-neck to the success of gene therapy. It is very challenging to develop non-viral nanocarriers to achieve ultra-high gene transfection efficiencies.

Programmable redox state of the nickel ion chain in DNA.

DNA is a nanowire in nature which chelates Ni ions and forms a conducting chain in its base-pairs (Ni-DNA). Each Ni ion in Ni-DNA exhibits low (Ni(2+)) or high (Ni(3+)) oxidation state and can be switched sequentially by applying bias voltage with different polarities and writing times. The ratio of low and high oxidation states of Ni ions in Ni-DNA represents a programmable multistate memory system with an added capacitive component, in which multistate information can be written, read, and erased.

The APE1 Asp/Asp genotype and the combination of APE1 Asp/Asp and hOGG1-Cys variants are associated with increased p53 mutation in non-small cell lung cancer.

Background: The hOGG1 Ser326Cys polymorphism is associated with lung cancer risk, but there are limited data regarding an association between the APE1 Asp148Glu polymorphism and lung cancer. Biological evidence shows that the hOGG1-Cys allele results in less DNA repair activity; however, this is not associated with p53 mutation in lung cancer. Therefore, we investigated whether an interaction between hOGG1 and APE1 is associated with the frequency of p53 mutation in lung cancer.

Activation of rabbit TLR9 by different CpG-ODN optimized for mouse and human TLR9.

Synthetic CpG-oligodeoxynucleotides (CpG-ODN) are potent adjuvants that accelerate and boost antigen-specific immune responses. Toll-like receptor 9 (TLR9) is the cellular receptor for these CpG-ODN. Previous studies have shown species-specific activation of mouse TLR9 (mTLR9) and human TLR9 (hTLR9) by their optimized CpG-ODN.

Reusable amperometric biosensor for measuring protein tyrosine kinase activity.

This work presents a simple, low-cost and reusable label-free method for detecting protein tyrosine kinase activity using a tyrosinase-based amperometric biosensor (tyrosine kinase biosensor). This method is based on the observation that phosphorylation can block the tyrosinase-catalyzed oxidation of tyrosine or tyrosyl residue in peptides. Therefore, the activity of p60c-src protein tyrosine kinase (Src) on the developed tyrosine kinase biosensor could be quickly determined when its specific peptide substrate, p60c-src substrate I, was used.

Development of single-vector Tet-on inducible systems with high sensitivity to doxycycline.

Single-vector Tet-on systems were developed to enable the tight regulation of transgenes in mammalian cells with a low dosage of doxycycline. Both the regulatory and the responsive units were integrated in a single vector and separated by a short DNA segment (214 bp). In the developed single-vector Tet-on systems, a high level of expression of the transgene can be induced by doxycycline at a concentration of as low as 1 ng/ml, which is 500-1,000 times lower than that usually utilized in other Tet-on systems.

Mammalian Ste20-like protein kinase 3 plays a role in hypoxia-induced apoptosis of trophoblast cell line 3A-sub-E.

Mammalian Ste20-like protein kinase 3 (Mst3) is a key player in inducing apoptosis in a variety of cell types and has recently been shown to participate in the signaling pathway of hypoxia-induced apoptosis of human trophoblast cell line 3A-sub-E (3A). It is believed that oxidative stress may occur during hypoxia and induce the expression of Mst3 in 3A cells via the activation of c-Jun N-terminal protein kinase 1 (JNK1). This hypothesis was demonstrated by the suppressive effect of dl-α-lipoic acid, a reactive oxygen species scavenger, in hypoxia-induced responses of 3A cells such as Mst3 expression, nitrotyrosine formation, JNK1 activation and apoptosis.

Fabrication of a carbon fiber paper as the electrode and its application toward developing a sensitive unmediated amperometric biosensor.

Carbon fiber paper (CFP), a material frequently used as the diffusion layer in fuel cells, was found recently to exhibit a potential as an electrode for the development of sensitive, unmediated biosensors. After nitrogen plasma treatment, the CFP exhibited a quasi-reversible behavior to the redox couple (e.g.

Neutron capture nuclei-containing carbon nanoparticles for destruction of cancer cells.

HeLa cells were incubated with neutron capture nuclei (boron-10 and gadolinium)-containing carbon nanoparticles, followed by irradiation of slow thermal neutron beam. Under a neutron flux of 6 x 10(11) n/cm(2) (or 10 min irradiation at a neutron flux of 1 x 10(9) n/cm(2) s), the percentages of acute cell death at 8 h after irradiation are 52, 55, and 28% for HeLa cells fed with BCo@CNPs, GdCo@CNPs, and Co@CNPs, respectively. The proliferation capability of the survived HeLa cells was also found to be significantly suppressed.

Improving the detection of hydrogen peroxide of screen-printed carbon paste electrodes by modifying with nonionic surfactants.

Nonionic surfactants, such as Triton X-100 and Tween-20, were shown in this study to improve the electrocatalytic activity of screen-printed carbon paste electrodes (SPCE). The electrochemical response of SPCE to hydrogen peroxide increased 8-10-fold with the modification of nonionic surfactants. In addition, the glucose biosensors fabricated from nonionic surfactant-modified SPCE exhibited 6.

Mammalian Ste20-like protein kinase 3 induces a caspase-independent apoptotic pathway.

In this study, it was shown that the mammalian sterile 20-like serine/threonine protein kinase 3 (Mst3) plays an essential role in the staurosporine-induced apoptosis of HeLa cells. The staurosporine-induced apoptosis was reduced by around 65% by the selective knockdown of Mst3 in stable clones, HeLa(siMst3). Although caspases were shown to be involved in the Mst3-mediated apoptosis, only 15-20% of staurosporine-induced apoptosis was suppressed by the caspase inhibitor, z-DEVD-fmk.

Biosignaling of mammalian Ste20-related kinases.

Sterile 20 (ste20) protein is an upstream ser/thr kinase in yeast, and several mammalian Ste20-like (MST) kinases have been identified. This review focuses on the signal transduction, interacting proteins, and potential biological function of MST1, 2, 3, and 4 kinases, since several novel signal pathways of these kinases have been characterized recently. MST1 and MST2 kinases play an important role in cell growth and apoptosis, and the signal pathways involves many important molecules including RAS, AKT, and FOXO3.

Mammalian Ste20-like protein kinase 3 mediates trophoblast apoptosis in spontaneous delivery.

The placenta is essential in transferring gases and nutrients from the mother to the developing fetus. Trophoblast apoptosis may cause labor or other pregnancy-related disorders. This study demonstrated the essential role of Mst3, a human Ste20-like protein kinase, in the oxidative stress-induced apoptosis of trophoblasts of term placenta in normal spontaneous delivery.

Application of SiO2-poly(dimethylsiloxane) hybrid material in the fabrication of amperometric biosensor.

Silica xerogel was widely used in the development of biosensors by coupling the desired biological components to various transducers. Unfortunately, the application of xerogels is limited due to their poor mechanical properties and poor structural maintenance of entrapped biomaterials. In this study, the availability of poly(dimethylsiloxane) (PDMS)-modified silica sol-gel (TEOS/PDMS Ormosil) glass in the immobilization of enzymes and its application in the fabrication of amperometric biosensor was investigated.

Fabrication of a miniature CMOS-based optical biosensor.

This work presents a novel, miniature optical biosensor by immobilizing horseradish peroxidase (HRP) or the HRP/glucose oxidase (GOx) coupled enzyme pair on a CMOS photosensing chip with a detection area of 0.5 mm x 0.5 mm.

Comparison of amperometric biosensors fabricated by palladium sputtering, palladium electrodeposition and Nafion/carbon nanotube casting on screen-printed carbon electrodes.

Different strategies, including palladium electrodeposition (Pd(CV)), Pd sputtering (Pd(S)) and Nafion-solubilized carbon nanotube casting (Nafion/CNT), were used to modify screen-printed carbon electrodes (SPCEs) for the fabrication of amperometric enzyme biosensors. The electrochemical properties of the bare and modified SPCEs and the optimal conditions for surface modification were determined. The electrochemical response of the bare SPCE to H(2)O(2) under the potential of 0.

Series quartz crystal sensor for remote bacteria population monitoring in raw milk via the Internet.

A remote monitoring system based on a piezoelectric quartz crystal (SPQC) sensor was developed for the determination of the bacteria population in raw milk. The system employs the Windows XP server operating system, and its programs for data acquisition, display and transmission were developed using the LabVIEW 7.1 programming language.

Zinc ion acts as a cofactor for serine/threonine kinase MST3 and has a distinct role in autophosphorylation of MST3.

We examined the metal ion cofactor preference for MST3 (mammalian Ste20-like kinase 3) of the Ste20 serine/threonine kinase family. Four metal ions (Mg(+2), Mn(+2), Zn(2+), and Co(2+)) activate endogenous, exogenous, and baculovirus-expressed recombinant MST3 within the physiological concentration range. In contrast, Fe(+2) and Ca(+2) do not function as MST3 cofactors.

Identification of V23RalA-Ser194 as a critical mediator for Aurora-A-induced cellular motility and transformation by small pool expression screening.

Human Aurora kinases have three gene family members: Aurora-A, Aurora-B, and Aurora-C. It is not yet established what the specificity of these kinases are and what signals relayed by their reactions. Therefore, we employed small pool expression screening to search for downstream substrates of Aurora-A.

Identification and characterization of the nuclear import and export signals of the mammalian Ste20-like protein kinase 3.

Mst3, a human Ste20-like protein kinase, has been recently demonstrated to undergo a caspase-mediated cleavage during apoptosis. The proteolytic cleavage of the C-terminus of Mst3 caused nuclear translocation of its kinase domain. This work provides evidence that Mst3 may contain a bipartite-like nuclear localization sequence (NLS) at the C-terminus of its kinase domain (residues 278-292).

Detection of serum uric acid using the optical polymeric enzyme biochip system.

An optical polymeric biochip system based on the complementary metal oxide semiconductor (CMOS) photo array sensor and polymeric enzyme biochip for rapidly quantitating uric acid in a one-step procedure was developed. The CMOS sensor was designed with N(+)/P-well structure and manufactured using a standard 0.5 microm CMOS process.