Potentiometric Multichannel Cytometer Microchip for High-throughput Microdispersion Analysis

The parallelization of microfluidic cytometry is expected to lead to considerably enhanced throughput enabling point-of-care diagnosis. In this article, the development of a microfluidic potentiometric multichannel cytometer is presented. Parallelized microfluidic channels sharing a fluid path inevitably suffer from interchannel signal crosstalk that results from electrical coupling within the microfluidic channel network. By employing three planar electrodes within a single detection channel, we electrically decoupled each channel unit, thereby enabling parallel analysis by using a single cytometer microchip with multiple microfluidic channels. The triple-electrode configuration is validated by analyzing the size and concentration of polystyrene microbeads (diameters: 1.99, 2.58, 3, and 3.68 μm; concentration range: ∼2 × 10⁵ mL^–1 to ∼1 × 10⁷ mL^–1) and bacterial microdispersion samples (<i>Bacillus subtilis</i>, concentration range: ∼4 × 10⁵ CFU mL^–1 to ∼3 × 10⁶ CFU mL^–1). Crosstalk-free parallelized analysis is then demonstrated using a 16-channel potentiometric cytometer (maximum cross-correlation coefficients |<i>r</i>|: < 0.13 in all channel combinations). A detection throughput of ∼48 000 s^–1 was achieved; the throughout can be easily increased with the degree of parallelism of a single microchip without additional technical complexities. Therefore, this methodology should enable high-throughput and low-cost cytometry

Magnetic Assembly of Nonmagnetic Particles into Photonic Crystal Structures

We report the rapid formation of photonic crystal structures by assembly of uniform nonmagnetic colloidal particles in ferrofluids using external magnetic fields. Magnetic manipulation of nonmagnetic particles with size down to a few hundred nanometers, suitable building blocks for producing photonic crystals with band gaps located in the visible regime, has been difficult due to their weak magnetic dipole moment. Increasing the dipole moment of magnetic holes has been limited by the instability of ferrofluids toward aggregation at high concentration or under strong magnetic field. By taking advantage of the superior stability of highly surface-charged magnetite nanocrystal-based ferrofluids, in this paper we have been able to successfully assemble 185 nm nonmagnetic polymer beads into photonic crystal structures, from 1D chains to 3D assemblies as determined by the interplay of magnetic dipole force and packing force. In a strong magnetic field with large field gradient, 3D photonic crystals with high reflectance (83%) in the visible range can be rapidly produced within several minutes, making this general strategy promising for fast creation of large-area photonic crystals using nonmagnetic particles as building blocks

Three-Dimensional Assembly of Nanoparticles from Charged Aerosols

The capability of assembling nanoparticles into a desired ordered pattern is a key to realize novel devices which are based not only on the unique properties of nanoparticles but also on the arrangements of nanoparticles. While two-dimensional arrays of nanoparticles have been successfully demonstrated by various techniques, a controlled way of building ordered arrays of three-dimensional (3D) nanoparticle structures remains challenging. We report that a variety of 3D nanoparticle structures can be formed in a controlled way based on the ion-induced focusing, electrical scaffold, and antenna effects from charged aerosols. Particle trajectory calculations successfully predict the whole process of 3D assembly. New surface enhanced Raman scattering substrates based on our 3D assembly were constructed as an example showing the viability of the present approach. This report extends the current capability of positioning nanoparticles on surface to another spatial dimension, which can serve as the foundation of future optical, magnetic, and electronic devices taking the advantage of multidimensions

Additional file 1 of The importance of critically short telomere in myelodysplastic syndrome

Additional file 1

Summary of bone marrow examinations of the three patients with refractory cytopenia of childhood (RCC).

BM, bone marrow; MDS, myelodysplastic syndromes; BM, bone marrow; MDS-EB2, myelodysplastic syndromes with excess blasts-2.</p

Clinical information and bone marrow findings of G-banding/FISH and targeted multigene sequencing in the three patients with myelodysplastic syndrome.

Clinical information and bone marrow findings of G-banding/FISH and targeted multigene sequencing in the three patients with myelodysplastic syndrome.</p

Heatmap showing gene variants of three MDS-EB2 patients with refractory cytopenia of childhood.

Of all variants filtered out by targeted multigene sequencing performed on three patients, only those observed in the myeloid malignancy predisposition genes, inherited thrombocytopenia predisposition genes, and somatic variants of myeloid malignancy-related genes are represented. A frameshift variant in THPO and a missense variant in NHP2 were observed in patient 1. A missense variant in DDX41 was observed in patient 2. A missense variant in FANCM and a splicing variant in BCOR were observed in patient 3. Inherited thrombocytopenia predisposition genes were identified based on guidelines in Bury et al. [1]. Myeloid malignancy predisposition genes were identified based on the WHO criteria and NCCN guidelines. The somatic variant was identified based on the NCCN guidelines and reported in the COSMIC database. MDS-EB2, myelodysplastic syndromes with excess blasts-2; WHO criteria, World Health Organization classification of tumors of hematopoietic and lymphoid tissues; NCCN, The National Comprehensive Cancer Network; COSMIC, Catalog Of Somatic Mutations In Cancer.</p

Three-Dimensional Assembly of Nanoparticles from Charged Aerosols

The capability of assembling nanoparticles into a desired ordered pattern is a key to realize novel devices which are based not only on the unique properties of nanoparticles but also on the arrangements of nanoparticles. While two-dimensional arrays of nanoparticles have been successfully demonstrated by various techniques, a controlled way of building ordered arrays of three-dimensional (3D) nanoparticle structures remains challenging. We report that a variety of 3D nanoparticle structures can be formed in a controlled way based on the ion-induced focusing, electrical scaffold, and antenna effects from charged aerosols. Particle trajectory calculations successfully predict the whole process of 3D assembly. New surface enhanced Raman scattering substrates based on our 3D assembly were constructed as an example showing the viability of the present approach. This report extends the current capability of positioning nanoparticles on surface to another spatial dimension, which can serve as the foundation of future optical, magnetic, and electronic devices taking the advantage of multidimensions

Three-Dimensional Assembly of Nanoparticles from Charged Aerosols

The capability of assembling nanoparticles into a desired ordered pattern is a key to realize novel devices which are based not only on the unique properties of nanoparticles but also on the arrangements of nanoparticles. While two-dimensional arrays of nanoparticles have been successfully demonstrated by various techniques, a controlled way of building ordered arrays of three-dimensional (3D) nanoparticle structures remains challenging. We report that a variety of 3D nanoparticle structures can be formed in a controlled way based on the ion-induced focusing, electrical scaffold, and antenna effects from charged aerosols. Particle trajectory calculations successfully predict the whole process of 3D assembly. New surface enhanced Raman scattering substrates based on our 3D assembly were constructed as an example showing the viability of the present approach. This report extends the current capability of positioning nanoparticles on surface to another spatial dimension, which can serve as the foundation of future optical, magnetic, and electronic devices taking the advantage of multidimensions

Three-Dimensional Assembly of Nanoparticles from Charged Aerosols

The capability of assembling nanoparticles into a desired ordered pattern is a key to realize novel devices which are based not only on the unique properties of nanoparticles but also on the arrangements of nanoparticles. While two-dimensional arrays of nanoparticles have been successfully demonstrated by various techniques, a controlled way of building ordered arrays of three-dimensional (3D) nanoparticle structures remains challenging. We report that a variety of 3D nanoparticle structures can be formed in a controlled way based on the ion-induced focusing, electrical scaffold, and antenna effects from charged aerosols. Particle trajectory calculations successfully predict the whole process of 3D assembly. New surface enhanced Raman scattering substrates based on our 3D assembly were constructed as an example showing the viability of the present approach. This report extends the current capability of positioning nanoparticles on surface to another spatial dimension, which can serve as the foundation of future optical, magnetic, and electronic devices taking the advantage of multidimensions