Novel microarrays for simultaneous serodiagnosis of multiple antiviral antibodies.

We developed an automated diagnostic system for the detection of virus-specific immunoglobulin Gs (IgGs) that was based on a microarray platform. We compared efficacies of our automated system with conventional enzyme immunoassays (EIAs). Viruses were immobilized to microarrays using a radical cross-linking reaction that was induced by photo-irradiation.

An automated multiplex specific IgE assay system using a photoimmobilized microarray.

An automated microarray diagnostic system for specific IgE using photoimmobilized allergen has been developed. Photoimmobilization is useful for preparing microarrays, where various types of biological components are covalently immobilized on a plate. Because the immobilization is based on a photo-induced radical cross-linking reaction, it does not require specific functional groups on the immobilized components.

Evaluation of prosthetic venous valves, fabricated by electrospinning, for percutaneous treatment of chronic venous insufficiency.

Chronic venous insufficiency (CVI) remains a major health problem worldwide. Direct venous valve surgical repair and venous segment transplantation are clinical options; however, they are highly invasive procedures. The objectives of this study were to fabricate prosthetic venous valves (PVVs) by electrospinning, for percutaneous treatment of CVI, and evaluate their hydrodynamic characteristics in vitro at the same locations and under the same flow conditions.

Analysis of gene expression changes associated with long-lasting synaptic enhancement in hippocampal slice cultures after repetitive exposures to glutamate.

We have previously shown that repetitive exposures to glutamate (100 muM, 3 min, three times at 24-hr intervals) induced a long-lasting synaptic enhancement accompanied by synaptogenesis in rat hippocampal slice cultures, a phenomenon termed RISE (for repetitive LTP-induced synaptic enhancement). To investigate the molecular mechanisms underlying RISE, we first analyzed the time course of gene expression changes between 4 hr and 12 days after repetitive stimulation using an original oligonucleotide microarray: "synaptoarray." The results demonstrated that changes in the expression of synapse-related genes were induced in two time phases, an early phase of 24-96 hr and a late phase of 6-12 days after the third stimulation.

miR-210 promotes osteoblastic differentiation through inhibition of AcvR1b.

Although microRNAs (miRNAs) are involved in many biological processes, the mechanisms whereby miRNAs regulate osteoblastic differentiation are poorly understood. Here, we found that BMP-4-induced osteoblastic differentiation of bone marrow-derived ST2 stromal cells was promoted and repressed after transfection of sense and antisense miR-210, respectively. A reporter assay demonstrated that the activin A receptor type 1B (AcvR1b) gene was a target for miR-210.

Improvement and analysis of a micro Raman probe.

A micro Raman probe (MRP) with a 600 microm diameter, which we previously reported as the narrowest achieved to date, was further improved by introducing high-quality optical filters and a collecting lens at the tip. We fabricated the MRP with a high collection efficiency, a wider collection wavelength, and a high signal-to-noise ratio. We compared two types of probes: one with a lens-tipped end and one with a flat tip.

miR-125b inhibits osteoblastic differentiation by down-regulation of cell proliferation.

Although various microRNAs regulate cell differentiation and proliferation, no miRNA has been reported so far to play an important role in the regulation of osteoblast differentiation. Here we describe the role of miR-125b in osteoblastic differentiation in mouse mesenchymal stem cells, ST2, by regulating cell proliferation. The expression of miR-125b was time-dependently increased in ST2 cells, and the increase in miR-125b expression was attenuated in osteoblastic-differentiated ST2 cells induced by BMP-4.

Narrow-band, widely electronically tuned frequency-shifted feedback laser.

The bandwidth of a frequency-shifted feedback Ti:sapphire laser is compressed through compensation for the shifted frequency inside the laser cavity by means of dual acousto-optic tunable filters (AOTFs) without the employment of an etalon. The laser wavelength can be tuned electronically in a 167-nm range by changes in the rf input to the two AOTFs. Wide-range tunability is achieved without mechanical adjustment or the addition of dispersive elements.

In vivo Raman study of the living rat esophagus and stomach using a micro-Raman probe under an endoscope.

A small endoscope system equipped with a micro Raman probe is developed for in vivo Raman measurements in living rats. The measurements are done under anesthesia and artificial respiration to minimize the impact on the rats. Raman spectra of living rat esophagus and stomach are successfully measured.

Development and validation of microarray-based assay for epidemiological study of MRSA.

We have developed a microarray-based assay for the genotyping of Staphylococcus aureus strains. A DNA microarray consisting of 221 genes with 390 oligonucleotide probes was designed to identify characteristic genes or gene alleles of S. aureus.

Retrospective evaluation of treatment outcome in Japanese children with complete unilateral cleft lip and palate. Part 1: Five-year-olds' index for dental arch relationships.

Objective: To evaluate the dental arch relationships of Japanese children with complete unilateral cleft lip and palate (UCLP) and to examine the 5-year-olds' index for its validity.

Design: Retrospective study and comparison with previous reports.

Subjects: One hundred thirty-six children with complete UCLP who received primary cheiloplasty and palatoplasty in the Kyushu University Hospital from 1966 to 1999.

Identification of synaptic activity-dependent genes by exposure of cultured cortical neurons to tetrodotoxin followed by its withdrawal.

Activity-dependent gene expression is one of the key mechanisms of synaptic plasticity that form the basis of higher order functions such as learning and memory. In the present study, we surveyed for activity-dependent genes by analyzing gene expression changes accompanying reversible inhibition of synaptic activity by tetrodotoxin (TTX) using two types of DNA microarrays; our focused oligo DNA microarray "Synaptoarray" and the commercially available high-density array. Cerebral cortical cells from E18 rat embryos were cultured for 14 days to ensure synaptogenesis, then treated with 1 muM TTX for 48 hr without detectable effect on cell viability.

Photo-cross-linked small-molecule microarrays as chemical genomic tools for dissecting protein-ligand interactions.

We have developed a unique photo-cross-linking approach for immobilizing a variety of small molecules in a functional-group-independent manner. Our approach depends on the reactivity of the carbene species generated from trifluoromethylaryldiazirine upon UV irradiation. It was demonstrated in model experiments that the photogenerated carbenes were able to react with every small molecule tested, and they produced multiple conjugates in most cases.

Detection of cRNA hybridized on a DNA chip using a tetrakis-acridinyl peptide cassette, consisting of TAP and partially self-complementary oligonucleotide, d[A18(TA)51].

A tetrakis-acridinyl peptide (TAP) cassette, consisting of a double-stranded region of alternating AT sequence bound to TAP and a single stranded overhanging sequence of continuous dA, was prepared by mixing TAP with d[A18(TA)51]. A TAP cassette could be applied to the fluorometric detection of hybridized DNA on the DNA chip, which was prepared by stamping a 45-meric DNA probe onto a gold-coated plastic chip using a high-precision spotter developed at RIKEN. Spots on the DNA chip were imaged by a CCD camera after hybridization with 65-meric target single-stranded DNAs carrying a continuous dA20 sequence (dA tail) on the DNA chip after treatment with a TAP cassette.

Efficient characterization for protein crystals using confocal Raman spectroscopy.

Confocal Raman spectroscopy was applied to the characterization of various states emerging in the screening of protein crystallization. Four main characterized states, namely single crystals, microcrystals, precipitates, and clear drops without solid materials, appear in a droplet for crystallization; the first three states should be critically distinguished and characterized because of the limitations of visual observation under an optical microscope. Using lysozyme and other proteins, crystallization was performed by the hanging drop vapor diffusion technique and was monitored through an automated confocal Raman system.

Intravascular Raman spectroscopic catheter for molecular diagnosis of atherosclerotic coronary disease.

An intravascular catheter for Raman spectroscopic detection and analysis of coronary atherosclerotic disease has been developed. The catheter, having an outer diameter of 2 mm, consisted of a side-view-type micro-Raman probe, an imaging fiber bundle, a working channel (injection drain), and a balloon. By inflating the balloon, the probe was brought close to the inner wall of a modeled blood flow system and detected a phantom target buried in the wall.

Fluorescence-suppressed Raman technique for quantitative analysis of protein solution using a micro-Raman probe, the shifted excitation method, and partial least squares regression analysis.

A practical Raman analyzing technique with suppression of the strong fluorescent background in order to obtain quantitative information is proposed in the present study. The technique is based on the shifted excitation method and partial least squares regression (PLSR) analysis. The Raman system consists of a single Raman spectrometer, a background-free electrically tunable Ti:Sapphire laser (BF-ETL), and a micro-Raman probe (MRP).

Automatic continuous scanning and random-access switching of mid-infrared waves generated by difference-frequency mixing.

We report the rapid tuning of mid-infrared waves beyond 5 microm emitted in difference-frequency mixing with an electronically tuned dual-wavelength Ti:Al2O3 laser used as a pumping source. Simultaneous rapid tuning of the dual wavelengths, which satisfy phase matching in AgGaS2, allows rapid random access switching and continuous tuning of mid-infrared wavelengths. In random-access switching, the mid-infrared wavelength is tuned every pulse shot at a repetition rate of 1 kHz.

Flexural rigidity of individual microtubules measured by a buckling force with optical traps.

We used direct buckling force measurements with optical traps to determine the flexural rigidity of individual microtubules bound to polystyrene beads. To optimize the accuracy of the measurement, we used two optical traps and antibody-coated beads to manipulate each microtubule. We then applied a new analytical model assuming nonaxial buckling.

Raman probe using a single hollow waveguide.

A simple Raman probe was realized using a single flexible hollow waveguide (HW). A HW coated with a silver film, which had reasonable transmission and little optical background noise, was used as a bidirectional transmission fiber for both the excitation and collection of Raman scattered light. The HW itself generated no Raman scattering or fluorescence noise during transmission.

Micro-optical fiber probe for use in an intravascular Raman endoscope.

We believe that we have developed the narrowest optical-fiber Raman probe ever reported, 600 microm in total diameter, that can be inserted into coronary arteries. The selection of suitable optical fibers, filters, and a processing method is discussed. Custom-made filters attached to the front end of a probe eliminate the background Raman signals of the optical fiber itself.

Monitoring synaptogenesis in the developing mouse cerebellum with an original oligonucleotide microarray.

Use of DNA microarrays in neuroscience have been limited to rough screening purposes, mainly because the reliability and sensitivity of available arrays are not high enough. Because only a few hundred to one thousand genes are usually found to change expression levels in most experiments, we attempted to develop a more quantitative array by the following strategies: 1) limit the genes to those relevant to the experimental system, 2) design oligonucleotide probes of specified molecular properties so that more stringent hybridization conditions can be employed, 3) place six spots per probe on one slide and use multiple normalization genes, and 4) use a new type of gold-coated slide with higher S/N ratio. Genes involved in the construction and functioning of the synapse were selected from the literature as well as experimentally by comparing cerebella from hypothyroid and control mice at postnatal day 15 (P15).

Excitation wavelength dependent surface-enhanced Raman spectra of a dipping film of azobenzene-containing long-chain fatty acid on a silver mirror.

Surface-enhanced Raman scattering (SERS) of dipping films of azobenzene-containing long-chain fatty acids, nAmH (n=8, 12, m=3, 5), on silver mirrors measured with a wide range of excitation wavelengths in the 457.9-1064 nm region is reported. The obtained Raman spectra show great SERS effect even with the 1064 nm excitation, and the excitation with 457.