Cytoskeletal elements in an acoelomorph worm, Praesagittifera naikaiensis

Acoel flatworms can move in a variety of ways such as muscular and ciliary movements via cytoskeletal elements and their neural regulations. However, those locomotive mechanisms have not yet been fully elucidated. In this study, we examined the distribution of cytoskeletal elements including filamentous actin (F-actin) and tubulin, and the neuroanatomical organization in an acoelomorph worm, Praesagittifera naikaiensis (P. naikaiensis). Video microscopy revealed the elongation/contraction and the bending/rotation processes, and the ciliary gliding movement of P. naikaiensis. Histochemical and morphological analysis demonstrated that F-actin networks of inner longitudinal and outer circular muscle fibers were positioned along the entire surface of the body, and that the average distance between the circular muscle fibers in the contracted organism was decreased in the anterior region compared with that in the elongated organism. Electron microscopy showed dense bodies on the muscle cells of P. naikaiensis, which indicates that those muscle cells have the appearance of vertebrate smooth muscle cells. Immunohistochemical analysis revealed that -tubulin-positive signals on the ciliary microtubules had close contact with the F-actin network, and that neurite bundles labelled with anti dSap47 antibody as a neuronal marker run along the anterior-posterior body axis. These results indicate that the well-organized cytoskeletal elements and their neural control systems are preserved in P. naikaiensis, and that their mechanisms involved in those regulation systems are similar to those vertebrate systems. Further studies are needed to clarify the physiological mechanisms underlying the muscular and ciliary movements in P. naikaiensis

The dilemma of nurses in the field of lifesaving：Literature review

The purpose of this study was to clarify the dilemmas that nurses have in the field of lifesaving through a literature review in Japan. As a result of analysis and discussion, it was found that there are four aspects to the dilemma that nurses have: “dilemma of giving priority to lifesaving,” “dilemma of performing the role as a nurse in a team,” “dilemma of the difficulty of practicing nursing under severe conditions,” and “dilemma of confronting oneself. It was inferred that these four aspects were related to each other. In addition, these dilemmas have two characteristics: social conflicts felt in the organization and intra-individual conflicts felt in oneself. Dilemmas are not necessarily harmful, even moderate dilemmas have positive aspects of functioning. By examining and managing dilemmas embraced by nurses, it is suggested that dilemmas can lead to their technical and spiritual growth, their improvement in the quality of nursing, and ultimately their organizational development

Identification of candidate molecular targets of the novel antineoplastic antimitotic NP-10

We previously reported the identification of a novel antimitotic agent with carbazole and benzohydrazide structures: N′-[(9-ethyl-9H-carbazol-3-yl)methylene]-2-iodobenzohydrazide (code number NP-10). However, the mechanism(s) underlying the cancer cell-selective inhibition of mitotic progression by NP-10 remains unclear. Here, we identified NP-10-interacting proteins by affinity purification from HeLa cell lysates using NP-10-immobilized beads followed by mass spectrometry. The results showed that several mitosis-associated factors specifically bind to active NP-10, but not to an inactive NP-10 derivative. Among them, NUP155 and importin β may be involved in NP-10-mediated mitotic arrest. Because NP-10 did not show antitumor activity in vivo in a previous study, we synthesized 19 NP-10 derivatives to identify more effective NP-10-related compounds. HMI83-2, an NP-10-related compound with a Cl moiety, inhibited HCT116 cell tumor formation in nude mice without significant loss of body weight, suggesting that HMI83-2 is a promising lead compound for the development of novel antimitotic agents

Sphingosine-1-phosphate receptor 1 expression in angiosarcoma : Possible role in metastasis and a potential therapeutic target

Sphingosine-1-phosphate (S1P) is a potent lipid mediator that has been implicated in the migration of lymphocytes and endothelial cells through S1P receptors. S1PR1 is strongly expressed in angiosarcoma, a malignant tumor of endothelial cell origin that has a high propensity for metastasis and poor prognosis; however, the pathological significance of S1PR1 expression is not clear. In this study, we investigated the effect of S1PR1 modulation on cell migration, and examined its potential role as a therapeutic target against metastatic dissemination of angiosarcoma. S1PR1 expression in the human angiosarcoma cell line MO-LAS was assessed by immunocytochemical examination and Western blotting. Effects of S1PR1- specific small interfering RNA (siRNA) and that of FTY720-P (a functional S1PR1-antagonist) on MO-LAS cell chemotactic migration towards sphingosine-1-phosphate (S1P) or 10% fetal bovine serum (FBS) were assessed by Transwell migration assay; wound healing assays for random cell migration were performed using a live cell analyzer. Immunostaining revealed high expression of S1PR1 on the MO-LAS cell membrane. Transwell and wound-healing assays showed that S1P enhanced chemotactic and random migration of MO-LAS cells, respectively. Inhibition of S1PR1 expression with siRNA significantly attenuated chemotaxis of cells towards S1P and 10% FBS. Further, FTY720-P strongly induced the internalization and degradation of S1PR1 even in the presence of serum containing S1P. It attenuated chemotactic cell migration of MO-LAS towards both S1P and serum, as well as the random motility of cells at nanomolar concentrations. These results suggest that the S1P/S1PR1 axis may be a potential therapeutic target for inhibition of angiosarcoma metastasis by controlling its cell motility

Contrast-enhanced Computed Tomography-Guided Percutaneous Cryoablation of Renal Cell Carcinoma in a Renal Allograft: First Case in Asia

Nephron-sparing treatment should be offered whenever possible to avoid dialysis in allograph cases. Cryoablation is a new treatment option for treating small-sized renal cell cancer (RCCs). We report a case of RCC arising in a kidney allograft treated by cryoablation. To our knowledge, this is the first case in Asia of RCC in a renal allograft treated using cryoablation. Contrast-enhanced CT-guided percutaneous renal needle biopsy and cryoablation were used to identify the RCC, which could not be identified by other techniques. The postoperative course was uneventful. Contrast-enhanced CT also showed no recurrence or metastases at the 6-month follow-up

赤芽球癆を合併したT-cell large granular lymphocyte leukemia の一例

T-cell large granular lymphocyte leukemia は長期(6か月以上)にわたる末梢血中の著明な大顆粒リンパ球(large granular lymphocyte;以下,LGL)のモノクローナルな増加によって特徴づけられる疾患で,しばしば赤芽球癆を伴うことが知られている.今回,我々はHCV陽性肝硬変患者に赤芽球癆を合併したT-LGLの1例を経験した.末梢血および骨髄塗抹標本では細胞質内に微細なアズール顆粒を有し,核異型を示すリンパ球の増加がみられ,末梢血および骨髄のフローサイトメトリーおよび骨髄吸引クロット標本の免疫組織化学で,CD3,CD8,CD57陽性リンパ球の増加が確認された.骨髄細胞のPCRではTCRβの再構成を認めず,TCRγおよびTCRδの再構成がみられた.またプレドニゾロン治療にてCD57陽性リンパ球の減少および赤芽球造血の回復が確認されたことから,赤芽球癆を合併したγδT-LGLと診断した.最近,T-LGLにはSTAT3あるいはSTAT5bのSHドメインの遺伝子変異が高頻度にみられることが報告されているが,本症例においては,これらの遺伝子変異は確認できなかった.T-cell large granular lymphocytic leukemia (T-LGL) is characterized by marked increase of monoclonal large granular lymphocytes (LGL) in the peripheral blood over the long term (6 months or more). It has been reported about 20% cases of T-LGL cases are associated with pure red cell aplasia (PRCA). Here, we describe a case of T-LGL associated with PRCA. This case was characterized by increase in the number of CD3+,CD8+,CD57+, and granzyme B-positive lymphocytes with fine azurophilic cytoplasmic granules and nuclear atypia in peripheral blood and bone marrow. The patient was diagnosed havingγδT-LGL because T-cell receptor (TCR)γ and TCRδ gene but not TCRβ gene rearrangement was detected by the PCR of the bone marrow cells. Prednisolone administration decreased in number of the LGL cells, accompanying recover of erythropoiesis. Although somatic mutations in the Src homology 2 domain of STAT3 or STAT5b gene are reported in 70% percent of the T-LGL with PRCA, such STAT mutations could not be detected in this case

Mature Myotubes Generated From Human-Induced Pluripotent Stem Cells Without Forced Gene Expression

遺伝子操作を加えずヒトiPS細胞から成熟骨格筋細胞を作製する技術を発明. 京都大学プレスリリース. 2022-05-30.Invention of technology to create mature skeletal muscle cells from iPS cells without genetic manipulation. 京都大学プレスリリース. 2022-05-30.Human-induced pluripotent stem cells (hiPSCs) are a promising tool for disease modeling and drug screening. To apply them to skeletal muscle disorders, it is necessary to establish mature myotubes because the onset of many skeletal muscle disorders is after birth. However, to make mature myotubes, the forced expression of specific genes should be avoided, as otherwise dysregulation of the intracellular networks may occur. Here, we achieved this goal by purifying hiPSC-derived muscle stem cells (iMuSC) by Pax7-fluorescence monitoring and antibody sorting. The resulting myotubes displayed spontaneous self-contraction, aligned sarcomeres, and a triad structure. Notably, the phenotype of sodium channels was changed to the mature type in the course of the differentiation, and a characteristic current pattern was observed. Moreover, the protocol resulted in highly efficient differentiation and high homogeneity and is applicable to drug screening