26 research outputs found

    Label-free single-cell separation and imaging of cancer cells using an integrated microfluidic system

    Get PDF
    The incidence of cancer is increasing worldwide and metastatic disease, through the spread of circulating tumor cells (CTCs), is responsible for the majority of the cancer deaths. Accurate monitoring of CTC levels in blood provides clinical information supporting therapeutic decision making, and improved methods for CTC enumeration are asked for. Microfluidics has been extensively used for this purpose but most methods require several post-separation processing steps including concentration of the sample before analysis. This induces a high risk of sample loss of the collected rare cells. Here, an integrated system is presented that efficiently eliminates this risk by integrating label-free separation with single cell arraying of the target cell population, enabling direct on-chip tumor cell identification and enumeration. Prostate cancer cells (DU145) spiked into a sample with whole blood concentration of the peripheral blood mononuclear cell (PBMC) fraction were efficiently separated and trapped at a recovery of 76.2 ± 5.9% of the cancer cells and a minute contamination of 0.12 ± 0.04% PBMCs while simultaneously enabling a 20x volumetric concentration. This constitutes a first step towards a fully integrated system for rapid label-free separation and on-chip phenotypic characterization of circulating tumor cells from peripheral venous blood in clinical practice

    Pressure-induced structural phase transition and new superconducting phase in UTe2

    Full text link
    We report on the crystal structure and electronic properties of the heavy fermion superconductor UTe2 at high pressure up to 11 GPa, as investigated by X-ray diffraction and electrical resistivity experiments. The X-ray diffraction measurements under high pressure using a synchrotron light source reveal anisotropic linear compressibility of the unit cell up to 3.5 GPa, while a pressure-induced structural phase transition is observed above 3.5-4GPa at room temperature, where the body-centered orthorhombic crystal structure with the space group Immm changes into a body-centered tetragonal structure with the space group I4/mmm. The molar volume drops abruptly at the critical pressure, while the distance between the first-nearest neighbor of U atoms increases, implying a switch from the heavy electronic states to the weakly correlated electronic states. Surprisingly, a new superconducting phase at pressures higher than 7 GPa was detected at Tsc above 2K with a relatively low upper-critical field, Hc2(0). The resistivity above 3.5GPa, thus, in the high-pressure tetragonal phase, shows a large drop below 230 K, which may also be related to a considerable change from the heavy electronic states to the weakly correlated electronic states.Comment: 11 pages, 9 figure

    miR2118-dependent U-rich phasiRNA production in rice anther wall development

    Get PDF
    Reproduction-specific small RNAs are vital regulators of germline development in animals and plants. MicroRNA2118 (miR2118) is conserved in plants and induces the production of phased small interfering RNAs (phasiRNAs). To reveal the biological functions of miR2118, we describe here rice mutants with large deletions of the miR2118 cluster. Our results demonstrate that the loss of miR2118 causes severe male and female sterility in rice, associated with marked morphological and developmental abnormalities in somatic anther wall cells. Small RNA profiling reveals that miR2118-dependent 21-nucleotide (nt) phasiRNAs in the anther wall are U-rich, distinct from the phasiRNAs in germ cells. Furthermore, the miR2118-dependent biogenesis of 21-nt phasiRNAs may involve the Argonaute proteins OsAGO1b/OsAGO1d, which are abundant in anther wall cell layers. Our study highlights the site-specific differences of phasiRNAs between somatic anther wall and germ cells, and demonstrates the significance of miR2118/U-phasiRNA functions in anther wall development and rice reproduction

    The CCR4–NOT deadenylase complex safeguards thymic positive selection by down-regulating aberrant pro-apoptotic gene expression

    Get PDF
    A repertoire of T cells with diverse antigen receptors is selected in the thymus. However, detailed mechanisms underlying this thymic positive selection are not clear. Here we show that the CCR4-NOT complex limits expression of specific genes through deadenylation of mRNA poly(A) tails, enabling positive selection. Specifically, the CCR4-NOT complex is up-regulated in thymocytes before initiation of positive selection, where in turn, it inhibits up-regulation of pro-apoptotic Bbc3 and Dab2ip. Elimination of the CCR4-NOT complex permits up-regulation of Bbc3 during a later stage of positive selection, inducing thymocyte apoptosis. In addition, CCR4-NOT elimination up-regulates Dab2ip at an early stage of positive selection. Thus, CCR4-NOT might control thymocyte survival during two-distinct stages of positive selection by suppressing expression levels of pro-apoptotic molecules. Taken together, we propose a link between CCR4-NOT-mediated mRNA decay and T cell selection in the thymus

    Middle Ear Carcinoid Tumor : Case Report and Literature Review

    Get PDF
    We herein report a rare case of a carcinoid tumor observed in the middle ear. The 51-year-old female patient presented to our hospital with an 8-year history of mild deafness and sensation of obstruction within the left ear. Otoscopic examination revealed a pinkish mass in the hypotympanum, which was visible through an intact tympanic membrane. Computed tomography (CT) of the temporal bone showed a well-circumscribed mass of soft tissue density filling the left hypotympanum. The provisional clinical diagnosis was cholesteatoma or another type of tumor (e.g. glomus jugulare tumor or facial nerve neurilemmoma). Transcanal tympanotomy was performed under general anesthesia to explore the lesion. At surgery, a well-delineated, encapsulated pinkish mass was found in the hypotympanum. It was not adherent to the tympanic membrane or ossicles. The mass arose, via a narrow pedicle, from the lining epithelium at the promontory. Complete resection of the mass was performed with careful clearance around the ossicles and epithelium at the promontory. Histological examination showed a carcinoid tumor composed of islands, cords, and nests of tumor cells in a fibrous stroma. Immunohistochemistry revealed granular cytoplasmic positivity for chromogranin A. No general symptoms of carcinoid syndrome were observed in this patient. Endoscopic examination revealed no evidence of other carcinoid tumors in the gastrointestinal and respiratory tracts. Eight years postoperatively, no evidence of recurrence or metastatic disease has been observed

    Feasibility of a cryopreservation of cultured human corneal endothelial cells.

    No full text
    Transparency of the cornea is essential for vision and is maintained by the corneal endothelium. Consequently, corneal endothelial decompensation arising from irreversible damage to the corneal endothelium causes severe vision impairment. Until recently, transplantation of donor corneas was the only therapeutic choice for treatment of endothelial decompensation. In 2013, we initiated clinical research into cell-based therapy involving injection of a suspension of cultured human corneal endothelial cells (HCECs), in combination with Rho kinase inhibitor, into the anterior chamber. The aim of the present study was to establish a protocol for cryopreservation of HCECs to allow large-scale commercial manufacturing of these cells. This study focused on the effects of various cryopreservation reagents on HCEC viability. Screening of several commercially available cryopreservation reagents identified Bambanker hRM as an effective agent that maintained a cell viability of 89.4% after 14 days of cryopreservation, equivalent to the cell viability of 89.2% for non-cryopreserved control cells. The use of Bambanker hRM and HCECs at a similar grade to that used clinically for cell based therapy (passage 3-5 and a cell density higher than 2000 cells/mm2) gave a similar cell density for cryopreserved HCECs to that of non-preserved control HCECs after 28 days of cultivation (2099 cells/mm2 and 2111 cells/mm2, respectively). HCECs preserved using Bambanker hRM grew in a similar fashion to non-preserved control HCECs and formed a monolayer sheet-like structure. Cryopreservation of HCECs has multiple advantages including the ability to accumulate stocks of master cells, to transport HCEC stocks, and to manufacture HCECs on demand for use in cell-based treatment of endothelial decompensation

    The Effects of Anxiety on the Recognition of Multisensory Emotional Cues with Different Cultural Familiarity

    No full text
    Anxious individuals have been shown to interpret others' facial expressions negatively. However, whether this negative interpretation bias depends on the modality and familiarity of emotional cues remains largely unknown. We examined whether trait-anxiety affects recognition of multisensory emotional cues (ie, face and voice), which were expressed by actors from either the same or different cultural background as the participants (ie, familiar in-group and unfamiliar out-group). The dynamic face and voice cues of the same actors were synchronized, and conveyed either congruent (eg, happy face and voice) or incongruent emotions (eg, happy face and angry voice). Participants were to indicate the perceived emotion in one of the cues, while ignoring the other. The results showed that when recognizing emotions of in-group actors, highly anxious individuals, compared with low anxious ones, were more likely to interpret others' emotions in a negative manner, putting more weight on the to-be-ignored angry cues. This interpretation bias was found regardless of the cue modality. However, when recognizing emotions of out-group actors, low and high anxious individuals showed no difference in the interpretation of emotions irrespective of modality. These results suggest that trait-anxiety affects recognition of emotional expressions in a modality independent yet cultural familiarity dependent manner

    Coenzyme-A-Independent Transacylation System; Possible Involvement of Phospholipase A2 in Transacylation

    No full text
    The coenzyme A (CoA)-independent transacylation system catalyzes fatty acid transfer from phospholipids to lysophospholipids in the absence of cofactors such as CoA. It prefers to use C20 and C22 polyunsaturated fatty acids such as arachidonic acid, which are esterified in the glycerophospholipid at the sn-2 position. This system can also acylate alkyl ether-linked lysophospholipids, is involved in the enrichment of arachidonic acid in alkyl ether-linked glycerophospholipids, and is critical for the metabolism of eicosanoids and platelet-activating factor. Despite their importance, the enzymes responsible for these reactions have yet to be identified. In this review, we describe the features of the Ca2+-independent, membrane-bound CoA-independent transacylation system and its selectivity for arachidonic acid. We also speculate on the involvement of phospholipase A2 in the CoA-independent transacylation reaction
    corecore