Interaction of neuron-specific K+-Cl− cotransporter, KCC2, with brain-type creatine kinase

Abstractγ-Aminobutyric acid, a major inhibitory neurotransmitter within the adult central nervous system, is also known to be excitatory at early developmental stages due to the elevated intracellular Cl− concentration. This functional change is primarily attributable to a K+-Cl− cotransporter, KCC2, the expression of which is developmentally regulated in neurons. However, little detail information is available concerning the intracellular regulation of KCC2 function. Here, we identify an interaction between KCC2 and brain-type creatine kinase by means of yeast two-hybrid screening. This interaction, which was also detected in cultured cells and brain extracts, might contribute to KCC2-mediated modulation of Cl− homeostasis

Investigation of a Plasma Gurney Flap for Lift Enhancement

RÉSUMÉ Des essais en soufflerie à des nombres de Reynolds (Re) entre 1,0 x 105 et 1,8 x 105 ont été faits avec une pale NACA 4424 sur laquelle étaient installés des volets Gurney de 2 % et 4 %. Quatre positions (à 85 %, 90 %, 95 % et 100 % de la corde) étaient testées afin de déterminer l’effet de l’emplacement du volet sur l’augmentation de la portance; une position plus près du bord d’attaque permettant d’entreposer des volets qui seraient déployables. L’effet de leur hauteur a aussi été analysé et, conformément à la théorie, un plus grand volet induit une plus grande augmentation de portance. Cela a été observé pour toutes les positions étudiées, tout comme une extension de la plage d’opération en comparaison à l’aile sans volet. Aussi, pour un angle d’attaque constant et pour une hauteur de volet donnée, tous les emplacements en amont du bord de fuite ont présenté des accroissements de portance plus importants qu’à 100 % de la corde. Pour un volet de 2 % de hauteur, la localisation optimale pour obtenir la plus grande augmentation de portance (ΔCL) est 85 % de la corde, alors que pour le contrôle du décrochage et la plage d’opération, il s’agit plutôt de 95 % de la corde. Un volet Gurney utilisant des actionneurs plasma a été conçu et testé à des Re variant de 1,2 x 105 à 1,8 x 105. Le « volet Gurney plasma » vise à éliminer la structure du volet Gurney conventionnel. Lors des essais, il était installé sur une pale NACA 4424 de 260 mm de corde et de 400 mm d’envergure. Les deux actionneurs plasma le composant étaient installés sur l’extrados et l’intrados du bord de fuite. Ils étaient activés de façon indépendante et les tests ont révélé que pris individuellement, ils contribuent de façon approximativement égale à l’augmentation de portance. Cette dernière est donc deux fois supérieure à celle qui serait obtenue avec une configuration à un seul actionneur. Alors que ΔCL avec un volet Gurney standard est surtout causé par le retardement de l’écoulement sous l’intrados, celui-ci est plutôt dû à l’accélération de l’air au-dessus de l’extrados dans le cas du « volet Gurney plasma ». Cela contribue à étendre encore plus la plage d’opération pour de basses vitesses d’écoulement. Tandis qu’une pale sans volet ou avec un volet de 1 % de hauteur décrochait à une vitesse de 4,6 m/s, le volet Gurney de 2 % de haut et le « volet Gurney plasma » demeuraient dans les limites d’opération stable. Tout dépendant de la vitesse de l’air et de la puissance appliquée aux actionneurs, ΔCL variait entre 0,02 et 0,18 pour le « volet Gurney plasma ». Puisque cette configuration présente deux actionneurs qui contribuent de façon égale à ΔCL, elle est environ deux fois meilleure que tout autre système à un seul actionneur plasma.----------Abstract Wind tunnel tests for 2% and 4% Gurney flaps on a NACA 4424 wing were conducted at Reynolds numbers ranging from 1.0 x 105 to 1.8 x 105. Four different flap locations, 85%, 90%, 95% and 100%, were tested to investigate flap location effect for lift improvement since an upstream location is feasible to store deployable flaps. In the flap height study, as reported in the literature, higher flaps provided larger lift. This trend was observed for all flap locations in this study. In the location study, all Gurney flap configurations showed a wider wing operational range than the baseline wing. All upstream flaps showed higher lift than the 100% location flap for a given angle of attack and flap height. The optimal location of a 2% Gurney flap in the study was the 85% location in terms improvement, ΔCL, and the 95% location in terms of stall control and wider operational range. A newly developed plasma “Gurney flap” was tested at Reynolds numbers ranging from 1.2 x 105 to 1.8 x 105. The plasma Gurney flap was intended to eliminate the physical structure of the Gurney flap and was installed on a 260 mm chord length and 400 mm wing span NACA 4424 airfoil. The Two SDBD plasma actuators comprising the plasma Gurney flap were installed individually on the suction side and the pressure side of the trailing edge. These two actuators were independently activated as well as the combined activation of the plasma Gurney flap. The tests revealed that each actuator individually contributes to the lift enhancement for nearly equal proportions, thus the combination of the two actuators performed twice as well as a single actuator. While the lift improvement by the physical Gurney flaps is mainly due to flow retardation on the pressures side, the lift enhancement of the plasma Gurney flap was mainly caused by the suction side flow acceleration. Because of these characteristics, the plasma Gurney flap is able to contribute wing operational range extension in the lower freestream velocity region. While the original and a 1% Gurney flap had stalled at 4.6 m/s freestream velocity, a 2% Gurney flap and the plasma Gurney flap wings remained within the wing operational ranges. The measured ΔCL ranged from 0.02 to 0.18, depending on the freestream velocity and the power applied to the plasma actuators. Because the actuator configuration allows the installation of two plasma actuators nearly equal contribution to lift improvement, the setup can generate approximately twice the effect of any other single plasma actuator configuration

Measuring effective orifice area of bileaflet mechanical valves in patients after aortic valve replacement using phase-contrast cine MR imaging

POSTER PRESENTATION2011 SCMR/Euro CMR Joint Scientific Sessions / Nice, France / 3-6 February 201

Aging and CMV Infection Affect Pre-existing SARS-CoV-2-Reactive CD8⁺ T Cells in Unexposed Individuals

加齢やサイトメガロウイルス感染が新型コロナウイルス反応性キラーT細胞に与える影響. 京都大学プレスリリース. 2021-08-23.Severe COVID-19 symptoms in the elderly are consistent with a weaker immune system. 京都大学プレスリリース. 2021-08-23.Age is a major risk factor for COVID-19 severity, and T cells play a central role in anti-SARS-CoV-2 immunity. Because SARS-CoV-2-cross-reactive T cells have been detected in unexposed individuals, we investigated the age-related differences in pre-existing SARS-CoV-2-reactive T cells. SARS-CoV-2-reactive CD4⁺ T cells from young and elderly individuals were mainly detected in the central memory fraction and exhibited similar functionalities and numbers. Naïve-phenotype SARS-CoV-2-reactive CD8⁺ T cell populations decreased markedly in the elderly, while those with terminally differentiated and senescent phenotypes increased. Furthermore, senescent SARS-CoV-2-reactive CD8⁺ T cell populations were higher in cytomegalovirus seropositive young individuals compared to seronegative ones. Our findings suggest that age-related differences in pre-existing SARS-CoV-2-reactive CD8+ T cells may explain the poor outcomes in elderly patients and that cytomegalovirus infection is a potential factor affecting CD8⁺ T cell immunity against SARS-CoV-2. Thus, this study provides insights for developing effective therapeutic and vaccination strategies for the elderly

Phenotypes of pain behavior in phospholipase C-related but catalytically inactive protein type 1 knockout mice

Phospholipase C-related inactive protein (PRIP) plays important roles in trafficking to the plasma membrane of GABAA receptor, which is involved in the dominant inhibitory neurotransmission in the spinal cord and plays an important role in nociceptive transmission. However, the role of PRIP in pain sensation remains unknown. In this study, we investigated the phenotypes of pain behaviors in PRIP type 1 knockout (PRIP-1 -/- ) mice. The mutant mice showed hyperalgesic responses in the second phase of the formalin test and the von Frey test as compared with those in wild-type mice. In situ hybridization studies of GABAA receptors revealed significantly decreased expression of γ2 subunit mRNA in the dorsal and ventral horns of the spinal cord in PRIP-1 -/- mice, but no difference in α1 subunit mRNA expression. β2 subunit mRNA expression was significantly higher in PRIP-1 -/- mice than in wild-type mice in all areas of the spinal cord. On the other hand, the slow decay time constant for the spontaneous inhibitory current was significantly increased by treatment with diazepam in wild-type mice, but not in PRIP-1 -/- mice. These results suggest that PRIP-1 -/- mice exhibit the changes of the function and subunits expression of GABAA receptor in the spinal cord, which may be responsible for abnormal pain sensation in these mice

The Identification of a Small Molecule Compound That Reduces HIV-1 Nef-Mediated Viral Infectivity Enhancement

Nef is a multifunctional HIV-1 protein that accelerates progression to AIDS, and enhances the infectivity of progeny viruses through a mechanism that is not yet understood. Here, we show that the small molecule compound 2c reduces Nef-mediated viral infectivity enhancement. When added to viral producer cells, 2c did not affect the efficiency of viral production itself. However, the infectivity of the viruses produced in the presence of 2c was significantly lower than that of control viruses. Importantly, an inhibitory effect was observed with Nef+ wild-type viruses, but not with viruses produced in the absence of Nef or in the presence of proline-rich PxxP motif-disrupted Nef, both of which displayed significantly reduced intrinsic infectivity. Meanwhile, the overexpression of the SH3 domain of the tyrosine kinase Hck, which binds to a PxxP motif in Nef, also reduced viral infectivity. Importantly, 2c inhibited Hck SH3-Nef binding, which was more marked when Nef was pre-incubated with 2c prior to its incubation with Hck, indicating that both Hck SH3 and 2c directly bind to Nef and that their binding sites overlap. These results imply that both 2c and the Hck SH3 domain inhibit the interaction of Nef with an unidentified host protein and thereby reduce Nef-mediated infectivity enhancement. The first inhibitory compound 2c is therefore a valuable chemical probe for revealing the underlying molecular mechanism by which Nef enhances the infectivity of HIV-1

A validation of the Japanese adaptation of the Big Five Inventory-2

The purpose of this study was to adapt a Japanese version of the Big Five Inventory-2 (BFI-2-J) to examine its factor structure, reliability, validity, and measurement invariance. The BFI-2-J assesses five domains and 15 facets of the Big Five personality traits. We analyzed two datasets: 487 Japanese undergraduates and 500 Japanese adults. The results of the principal component analysis and confirmatory factor analysis revealed that the domain-facet structure of the BFI-2-J was similar to that of other language versions. The reliability of the BFI-2-J is sufficient. The correlation coefficients between the BFI-2-J and the other Big Five and self-esteem measures supported convergent and discriminant validity. Moreover, we confirmed measurement invariance across age and sex groups in domain-level and facet-level models. The results suggest that the BFI-2-J is a good instrument for measuring the Big Five personality traits and their facets in Japan. The BFI-2-J is expected to be useful in Japanese personality research and international comparative research

Case report: A case of unilateral combined central retinal vein occlusion, incomplete central retinal artery occlusion, and papillitis following a third dose of COVID-19 vaccination

PurposeThe aim of this study was to present a case of severe visual loss due to retinal arteriovenous occlusion and papillitis in one eye following vaccination against coronavirus disease (COVID-19).MethodsA 45-year-old man undergoing treatment for hypertension had severely reduced visual acuity in the right eye 1 day after receiving a third dose of a COVID-19 vaccine manufactured by Moderna. Clinical examination showed that the best-corrected visual acuity in the right eye was counting fingers. Other findings included circumferential retinal hemorrhage, perimacular ischemic color, severe macular edema, and severe optic disc swelling, indicating the presence of central retinal vein occlusion, incomplete central retinal artery occlusion, and papillitis. Based on the possibility of post-vaccination inflammation and/or abnormal immune response, three courses of steroid pulse therapy were administered, and the visual acuity slightly improved to 20/1,000.ResultsThree months after the onset of symptoms, macular edema disappeared; conversely, retinal thinning of the macula and extensive non-perfusion areas mainly on the nasal side were noted.ConclusionThe findings in this case suggest that inflammation and abnormal immune response after receiving a COVID-19 vaccination may lead to combined retinal arteriovenous occlusion and papillitis

CDK8/19 inhibition plays an important role in pancreatic β-cell induction from human iPSCs

サイクリン依存性キナーゼCDK8/19阻害はヒトiPS細胞からの膵島様細胞への分化誘導において重要な役割を果たす. 京都大学プレスリリース. 2023-02-27.A safer method of generating pancreatic islet-like cells from human iPS cells by inhibiting cyclin-dependent kinase CDK8/19. 京都大学プレスリリース. 2023-03-08.[Background] Transplantation of differentiated cells from human-induced pluripotent stem cells (hiPSCs) holds great promise for clinical treatments. Eliminating the risk factor of malignant cell transformation is essential for ensuring the safety of such cells. This study was aimed at assessing and mitigating mutagenicity that may arise during the cell culture process in the protocol of pancreatic islet cell (iPIC) differentiation from hiPSCs. [Methods] We evaluated the mutagenicity of differentiation factors used for hiPSC-derived pancreatic islet-like cells (iPICs). We employed Ames mutagenicity assay, flow cytometry analysis, immunostaining, time-resolved fluorescence resonance energy transfer-based (TR-FRET) cell-free dose–response assays, single-cell RNA-sequencing and in vivo efficacy study. [Results] We observed a mutagenic effect of activin receptor-like kinase 5 inhibitor II (ALK5iII). ALK5iII is a widely used β-cell inducer but no other tested ALK5 inhibitors induced β-cells. We obtained kinase inhibition profiles and found that only ALK5iII inhibited cyclin-dependent kinases 8 and 19 (CDK8/19) among all ALK5 inhibitors tested. Consistently, CDK8/19 inhibitors efficiently induced β-cells in the absence of ALK5iII. A combination treatment with non-mutagenic ALK5 inhibitor SB431542 and CDK8/19 inhibitor senexin B afforded generation of iPICs with in vitro cellular composition and in vivo efficacy comparable to those observed with ALK5iII. [Conclusion] Our findings suggest a new risk mitigation approach for cell therapy and advance our understanding of the β-cell differentiation mechanism