311 research outputs found
Construction of a [15]Annulenone-[15]annulenyl Ion Cycle
Previously, we have reported the synthesis of furanoid
[15]annulenones and their protonated species. With the benefits of
FT NMR spectroscopy, some of experiments have now been reinvestigated.
The annulenone may undergo dynamic conformational changes
to provide an interesting cycle, which can be driven by protonation-
deprotonation sequence
Construction of a [15]Annulenone-[15]annulenyl Ion Cycle
Previously, we have reported the synthesis of furanoid
[15]annulenones and their protonated species. With the benefits of
FT NMR spectroscopy, some of experiments have now been reinvestigated.
The annulenone may undergo dynamic conformational changes
to provide an interesting cycle, which can be driven by protonation-
deprotonation sequence
マウスの神経細胞において、Ischemic postconditioningはmitochondrial permeability transition poreとKATPチャネルの開口を介してNMDA受容体電流を低下させる。
Ischemic postconditioning (PostC) is known to reduce cerebral ischemia/reperfusion (I/R) injury; however, whether the opening of mitochondrial ATP-dependent potassium (mito-KATP) channels and mitochondrial permeability transition pore (mPTP) cause the depolarization of the mitochondrial membrane that remains unknown. We examined the involvement of the mito-KATP channel and the mPTP in the PostC mechanism. Ischemic PostC consisted of three cycles of 15 s reperfusion and 15 s re-ischemia, and was started 30 s after the 7.5 min ischemic load. We recorded N-methyl-D-aspartate receptors (NMDAR)-mediated currents and measured cytosolic Ca²⁺ concentrations, and mitochondrial membrane potentials in mouse hippocampal pyramidal neurons. Both ischemic PostC and the application of a mito-KATP channel opener, diazoxide, reduced NMDAR-mediated currents, and suppressed cytosolic Ca2+ elevations during the early reperfusion period. An mPTP blocker, cyclosporine A, abolished the reducing effect of PostC on NMDAR currents. Furthermore, both ischemic PostC and the application of diazoxide potentiated the depolarization of the mitochondrial membrane potential. These results indicate that ischemic PostC suppresses Ca²⁺ influx into the cytoplasm by reducing NMDAR-mediated currents through mPTP opening. The present study suggests that depolarization of the mitochondrial membrane potential by opening of the mito-KATP channel is essential to the mechanism of PostC in neuroprotection against anoxic injury.博士(医学)・甲第781号・令和3年3月15日© Springer Science+Business Media, LLC, part of Springer Nature 2020This is a post-peer-review, pre-copyedit version of an article published in Cellular and molecular neurobiology. The final authenticated version is available online at: http://dx.doi.org/10.1007/s10571-020-00996-y
Wind- and Operation-Induced Vibration Measurements of the Main Reflector of the Nobeyama 45 m Radio Telescope
As deformations of the main reflector of a radio telescope directly affect
the observations, the evaluation of the deformation is extremely important.
Dynamic characteristics of the main reflector of the Nobeyama 45 m radio
telescope, Japan, are measured under two conditions: The first is when the
pointing observation is in operation, and the second is when the reflector is
stationary and is subjected to wind loads when the observation is out of
operation. Dynamic characteristics of the main reflector are measured using
piezoelectric accelerometers. When the telescope is in operation, a vibration
mode with one nodal line horizontally or vertically on the reflector is
induced, depending on whether the reflector is moving in the azimuthal or
elevational planes, whereas under windy conditions, vibration modes that have
two to four nodal lines are simultaneously induced. The predominant mode is
dependent on the direction of wind loads.Comment: Accepted for publication in Journal of Vibration Engineering &
Technologie
Development of an appropriate simple suspension method for valganciclovir medication
Background
Valganciclovir (VGC) is essential for preventing cytomegalovirus infections after transplants in adult and pediatric patients. In pediatric patients, VGC tablets have to be pulverized so that they can be delivered via nasogastric tubes. The “simple suspension method” is usually used to suspend tablets in hot water in Japan. However, the optimal suspension conditions and metering methods for preparing VGC suspensions using the simple suspension method are unclear. The purpose of this study was to clarify these issues.
Methods
VGC tablets were suspended in water (initial water temperature: 25 °C or 55 °C) using the simple suspension method. The residual rate of VGC after it had been suspended in hot water was determined using HPLC. In addition, the suspended solution was passed through 6, 8, and 12 Fr. gavage tubes. The VGC concentrations of suspensions produced using different preparation methods were also determined using HPLC.
Results
Cracking the surfaces of VGC tablets and suspending them in water at an initial temperature of 55 °C was effective at dissolving the tablets. The VGC concentration of the suspension remained stable for at least 80 min. Furthermore, the VGC concentration remained stable for 48 h during cold dark storage. Cracking the surfaces of VGC tablets could be a more effective metering method than preparing powder from VGC tablets. In addition, little VGC remained in 6, 8, or 12 Fr. gavage tubes after VGC solution was passed through them.
Conclusion
The amount of VGC should be measured carefully when preparing VGC solutions using the simple suspension method
Refinement of Conditions of Point-Contact Current Imaging Atomic Force Microscopy for Molecular-Scale Conduction Measurements
Change of CD20 Expression in Diffuse Large B-Cell Lymphoma Treated with Rituximab, an Anti-CD20 Monoclonal Antibody: A Study of the Osaka Lymphoma Study Group
Change of CD20 expression was examined in cases of diffuse large B-cell lymphoma (DLBCL). CD20 expression after treatment with anti-CD20 antibody (rituximab, Rx) for DLBCL was examined in 23 cases who received serial biopsy by immunohistochemistry (IHC) and flow cytometry (FCM). CD20– by IHC and/or FCM was defined as CD20–. Four cases were CD20– at initial biopsy but became CD20+ after chemotherapy with Rx (CH-R) (group A). Recurrent tumors in three group A cases became resistant to CH-R. Initial and recurrent tumors were CD20+ before and after CH-R in 17 cases (group B). Tumors before CH-R were CD20– in two cases (group C) and continued to be CD20– in one and turned CD20+ in the other with survival time after the relapse of 8 and 23 months, respectively. Evaluation of CD20 expression with immunohistochemical and flow cytometric methods is used for the prediction of responsiveness of relapsed DLBCL for CH-R
A subtype of olfactory bulb interneurons is required for odor detection and discrimination behaviors
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