Orthogonally-tunable and ER-targeting fluorophores detect avian influenza virus early infection.

Cell-based assays can monitor virus infection at a single-cell level with high sensitivity and cost-efficiency. For this purpose, it is crucial to develop molecular probes that respond selectively to physiological changes in live cells. We report stimuli-responsive light-emitters built on a T-shaped benzimidazole platform, and consecutive borylation reactions to produce a library of homologs displaying systematic changes in fluorescence quantum yield and environmental sensitivity.

A Near-Infrared Probe Tracks and Treats Lung Tumor Initiating Cells by Targeting HMOX2.

Tumor initiating cells (TIC) are resistant to conventional anticancer therapy and associated with metastasis and relapse in cancer. Although various TIC markers and their antibodies have been proposed, it is limited to the use of antibodies for in vivo imaging or treatment of TIC. In this study, we discovered heme oxygenase 2 (HMOX2) as a novel biomarker for TIC and developed a selective small molecule probe TiNIR (tumor initiating cell probe with near infrared).

Reinvestigation of an O-Salicylaldehyde Ester Functional Group in Aqueous Buffer and Discovery of a Coumarin Scaffold Probe for Selective N-Terminal Cysteine Labeling.

Many intracellular proteins are metabolically unstable, and their half-life was known to be controlled by the "N-end rule," that is, the N-terminal residue controlled protein stability. To visualize or measure the cellular stability of a protein, depending on the N-terminal residues, attention is being paid to the development of selective labeling methods for individual N-terminal amino acids. However, there are only a limited number of functional groups available for specific N-terminal amino acid labeling in a biological environment.

Discrimination of Avian Influenza Virus Subtypes using Host-Cell Infection Fingerprinting by a Sulfinate-based Fluorescence Superoxide Probe.

The current gold-standard diagnosis method for avian influenza (AI) is an embryonic egg-based hemagglutination assay followed by immunoblotting or PCR sequencing to confirm subtypes. It requires, however, specialized facilities to handle egg inoculation and incubation, and the subtyping methods relied on costly reagents. Now, the first differential sensing approach to distinguish AI subtypes is demonstrated using series of cell lines and a fluorescent sensor.

Chloro-Functionalized Photo-crosslinking BODIPY for Glutathione Sensing and Subcellular Trafficking.

Glutathione (GSH) is one of major antioxidants inside cells that regulates oxidoreduction homeostasis. Recently, there have been extensive efforts to visualize GSH in live cells, but most of the probes available today are simple detection sensors and do not provide details of cellular localization. A new fluorescent probe (pcBD2-Cl), which is cell permeable and selectively reacts with GSH in situ, has been developed.

Bulk Aggregation Based Fluorescence Turn-On Sensors for Selective Detection of Progesterone in Aqueous Solution.

Steroids are polycyclic compounds that share tetracyclic ring as core scaffold, and selective detection of a steroid is challenging owing to their structural similarities. The discovery of chemosensors that recognize progesterone by alteration of self-aggregation state is described, and these show significant fluorescence turn-on. A self-aggregated 48-membered dansyl library was screened against a series of metabolites in aqueous buffer and discovered two compounds (PG-1, PG-2) exhibited exceptional selectivity for progesterone.

Photo-affinity labeling (PAL) in chemical proteomics: a handy tool to investigate protein-protein interactions (PPIs).

Protein-protein interactions (PPIs) trigger a wide range of biological signaling pathways that are crucial for biomedical research and drug discovery. Various techniques have been used to study specific proteins, including affinity chromatography, activity-based probes, affinity-based probes and photo-affinity labeling (PAL). PAL has become one of the most powerful strategies to study PPIs.

Combinatorial Dansyl Library and its Applications to pH-Responsive Probes.

Herein, we report the first 48-membered, dansyl-based, combinatorial fluorescent library. From the electronic and structural properties of the probes, we analyzed their optical properties and chemical yields, with an average of 49 %. The molecules were examined for their pH responses, and DS-2 and DS-45 showed blue-shifts, whereas DS-7 and DS-40 showed red-shifts in wavelength with increasing pH.

Magnetic-assembly mechanism of superparamagneto-plasmonic nanoparticles on a charged surface.

One-dimensional magnetoplasmonic nanochains (MPNCs) were self-assembled using Au-coated Fe3O4 core-shell superparamagnetic nanoparticles (Fe3O4@Au NPs) by applying an external static magnetic field. The assembly mechanism of the Fe3O4@Au NPs was investigated thoroughly, revealing that substrate-particle interactions, van der Waals forces, and magnetic forces play important roles in the formation and control of the MPNCs. Magnetic force microscopy (MFM) and vibrating sample magnetometry (VSM) were used to study the magnetic properties of the MPNCs, which were compared with those of Fe3O4 nanochains.

Rational design of a photo-crosslinking BODIPY for in situ protein labeling.

Photo-crosslinking agents have emerged as critical tools to investigate protein-protein interactions in complex proteomes, but there are few photocrosslinkers available at the moment. Here, we report the first rational design of a photo-crosslinking BODIPY fluorophore (pcBD) and its biological application for biomolecule labeling. As a photosensitizing functional motif, an aryl ketone group was incorporated into the BODIPY fluorophore, and a series of proteins were labeled by pcBD compounds upon UV irradiation.

Lower urinary tract symptoms and erectile dysfunction in men with type 2 diabetes mellitus.

Purpose: To assess the prevalence of lower urinary tract symptoms (LUTS) and erectile dysfunction (ED) and the relationships between LUTS, ED, depression, and other factors in Korean men with type 2 diabetes mellitus (T2DM).

Methods: This cross-sectional study included 124 male patients with T2DM who attended a university hospital diabetes clinic between October 2010 and April 2012. Data were collected using structured interviews and chart reviews.

Difference between Toxicities of Iron Oxide Magnetic Nanoparticles with Various Surface-Functional Groups against Human Normal Fibroblasts and Fibrosarcoma Cells.

Recently, many nanomedical studies have been focused on magnetic nanoparticles (MNPs) because MNPs possess attractive properties for potential uses in imaging, drug delivery, and theranostics. MNPs must have optimized size as well as functionalized surface for such applications. However, careful cytotoxicity and genotoxicity assessments to ensure the biocompatibility and biosafety of MNPs are essential.

Subtle cytotoxicity and genotoxicity differences in superparamagnetic iron oxide nanoparticles coated with various functional groups.

Superparamagnetic iron oxide nanoparticles (SPIONs) have been widely utilized for the diagnosis and therapy of specific diseases, as magnetic resonance imaging (MRI) contrast agents and drug-delivery carriers, due to their easy transportation to targeted areas by an external magnetic field. For such biomedical applications, SPIONs must have multifunctional characteristics, including optimized size and modified surface. However, the biofunctionality and biocompatibility of SPIONs with various surface functional groups of different sizes have yet to be elucidated clearly.

Fabrication of uniform au-carbon nanofiber by two-step low temperature decomposition.

This paper presents a facile and efficient way to prepare carbon nanofibers ornamented with Au nanoparticles (Au/CNFs). Gold nanoparticles were first deposited in the channels of an anodized aluminum oxide (AAO) membrane by thermal decomposition of HAuCl4and then carbon nanofibers were produced in the same channels loaded with the Au nanoparticles by decomposition of sucrose at 230 °C. An electron microscopy study revealed that the carbon nanofibers, ~10 nm thick and 6 μm long, were decorated with Au nanoparticles with a diameter of 10 nm.