A variety of methods have been reported using polymerase chain reaction (PCR)-based nucleic acid testing (NAT) because of its potential to be used in highly sensitive inspection systems. Among these NATs, fusion-PCR (also called as overlap-extension-PCR) has been focused on this study and adopted to generate the fused amplicon composed of plural marker gene fragments for detection. Generally, conventional agarose gel electrophoresis followed by gel staining is employed to check the PCR results.
View Article and Find Full Text PDFPlasma thrombopoietin (TPO) measurements help distinguish between different types of thrombocytopenia but are not feasible in routine clinical practice. We developed a fully automated quantitative chemiluminescent enzyme immunoassay (CLEIA) for measuring TPO (TPO-CLEIA), which is a one-step sandwich-type assay. This assay utilizes a mouse monoclonal capture antibody, which has the neutralizing epitope of the interaction between TPO and the TPO receptor, and a newly generated rabbit monoclonal detector antibody.
View Article and Find Full Text PDFSmall-angle X-ray scattering (SAXS) coupled with computed tomography (CT), denoted SAXS-CT, has enabled the spatial distribution of the characteristic parameters ( size, shape, surface, length) of nanoscale structures inside samples to be visualized. In this work, a new scheme with Tikhonov regularization was developed to remove the effects of artifacts caused by streak scattering originating from the reflection of the incident beam in the contour regions of the sample. The noise due to streak scattering was successfully removed from the sinogram image and hence the CT image could be reconstructed free from artifacts in the contour regions.
View Article and Find Full Text PDFGrazing-incidence small-angle X-ray scattering (GISAXS) coupled with computed tomography (CT) has enabled the visualization of the spatial distribution of nanostructures in thin films. 2D GISAXS images are obtained by scanning along the direction perpendicular to the X-ray beam at each rotation angle. Because the intensities at the positions contain nanostructural information, the reconstructed CT images individually represent the spatial distributions of this information ( size, shape, surface, characteristic length).
View Article and Find Full Text PDFThree-dimensional (3D) cell culture systems have been used to obtain multicellular spheroidal cell aggregates, or spheroids, from cancer cells. However, it is difficult to efficiently prepare large tumor-derived spheroids from cancer cells. To circumvent this problem, we here used a tool equipped with removal membrane, called Spheroid Catch, for the selection and enrichment of large-sized and/or size-matched spheroids from human squamous cell carcinoma (SAS cells) without loss of recovery.
View Article and Find Full Text PDFUsing grazing-incidence small-angle scattering (GISAXS) with computed tomography (CT), we have individually reconstructed the spatial distribution of a thin gold (Au) layer buried under a thin poly(styrene-b-2-vinylpyridine) (PS-b-P2VP) layer. Owing to the difference between total reflection angles of Au and PS-b-P2VP, the scattering profiles for Au nanoparticles and self-assembled nanostructures of PS-b-P2VP could be independently obtained by changing the X-ray angle of incidence. Reconstruction of scattering profiles allows one to separately characterize spatial distributions in Au and PS-b-P2VP nanostructures.
View Article and Find Full Text PDFCyclin G1 (CycG1) and Cyclin G2 (CycG2) play similar roles during the DNA damage response (DDR), but their detailed roles remain elusive. To investigate their distinct roles, we generated knockout mice deficient in CycG1 (G1KO) or CycG2 (G2KO), as well as double knockout mice (DKO) deficient in both proteins. All knockouts developed normally and were fertile.
View Article and Find Full Text PDFWithaferin A (WA), a major bioactive component of the Indian herb Withania somnifera, induces cell death (apoptosis/necrosis) in multiple types of tumor cells, but the molecular mechanism underlying this cytotoxicity remains elusive. We report here that 2 μM WA induced cell death selectively in androgen-insensitive PC-3 and DU-145 prostate adenocarcinoma cells, whereas its toxicity was less severe in androgen-sensitive LNCaP prostate adenocarcinoma cells and normal human fibroblasts (TIG-1 and KD). WA also killed PC-3 cells in spheroid-forming medium.
View Article and Find Full Text PDFNerve growth factor (NGF) is a well-known neurotrophic factor and the NGF signaling through the receptor, TrkA, plays important roles in regulating neuronal differentiation and survival. A recent study has demonstrated that the TrkAs expressed in undifferentiated PC12 cells were associated with caveolae, which were invaginated small pits on the plasma membrane. Caveolae are frequently seen in many cell types such as endothelial cells, fibroblasts and hepatocytes, but few in neurons.
View Article and Find Full Text PDFHighly crystallized GeO2 nanosheets were synthesized by hydrolysis and condensation reactions of germanium alkoxide using a 2-dimensional flat thin lamellar phase water layer containing surfactant molecules at the liquid-liquid interface as a confined reaction field.
View Article and Find Full Text PDFWe constructed chimeric proteins that consist of two green fluorescent protein variants, EBFP and EGFP, connected by flexible linkers, (GGGGS)n (n = 3 approximately 4), and helical linkers, (EAAAK)n (n = 2 approximately 5). The conformations of the chimeric proteins with the various linkers were evaluated using small-angle X-ray scattering (SAXS). The SAXS experiments showed that introducing the short helical linkers (n = 2 approximately 3) causes multimerization, while the longer linkers (n = 4 approximately 5) solvate monomeric chimeric proteins.
View Article and Find Full Text PDFWe examined the effects of the expansion of glutamine repeats on the early stage of protein fibrillization. Small-angle x-ray scattering (SAXS) and electron microscopic studies revealed that the elongation of polyglutamine from 35 to 50 repeats in protein induced a large assembly of the protein upon incubation at 37 degrees C and that its formation was completed in approximately 3 h. A bead modeling procedure based on SAXS spectra indicated that the largely assembled species of the protein, quasi-aggregate, is composed of 80 to approximately 90 monomers and a bowl-like structure with long and short axes of 400 and 190 A, respectively.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
February 2003
Structure self-assembling in the late stage spinodal decomposition of a polymer blend at its critical composition has been explored by laser-scanning confocal microscopy with particular emphasis on the effects of confinement (dimensionality) and preferential wetting of solid surface by one of the constituent polymers. A mixture of deuterated polybutadiene and polybutadiene (PB) with relatively narrow thickness (D congruent with 55 microm) was observed in three dimensions over the entire thickness. Formation of a wetting layer was clearly observed near the glass surface, while a bicontinuous structure evolved in the middle of the specimen.
View Article and Find Full Text PDFTo examine the effects of aggregation-inducing motifs related to neurodegenerative diseases on amyloid formation of host protein, we prepared several chimera myoglobins, in which various aggregation-inducing motifs were inserted. The focused aggregation-inducing motifs included five (R5) or two (R2) oligopeptide repeats in yeast Sup35p, five octapeptide repeats (OPR) in the human prion protein, a nonamyloid beta component (NAC) in alpha-synuclein, and tandem repeats of 50 glutamines (Q50). Circular dichroism and infrared spectroscopies suggested that the OPR, R5, and Q50 motifs formed an antiparallel beta sheet as well as a random coil, whereas the R2 and NAC motifs mainly formed random coils.
View Article and Find Full Text PDFA striated muscle fiber consists of thousands of myofibrils with crystalline hexagonal myofilament lattices. Because the lattices are randomly oriented, the fiber gives rise to an equatorial x-ray diffraction pattern, which is essentially a rotary-averaged "powder diffraction," carrying only information about the distance between the lattice planes. We were able to record an x-ray diffraction pattern from a single myofilament lattice, very likely originating from a single myofibril from the flight muscle of a bumblebee, by orienting the incident x-ray microbeam along the myofibrillar axis (end-on diffraction).
View Article and Find Full Text PDFTo investigate protein folding dynamics in terms of compactness, we developed a continuous-flow mixing device to make small-angle x-ray scattering measurements with the time resolution of 160 micros and characterized the radius of gyration (R(g)) of two folding intermediates of cytochrome c (cyt c). The early intermediate possesses approximately 20 A of R(g), which is smaller by approximately 4 A than that of the acid-unfolded state. The R(g) of the later intermediate is approximately 18 A, which is close to that of the molten globule state.
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