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Heterometallic Pd(II)-Ni(II) complexes with meso-substituted dibenzotetraaza[14]annulene: double C-H bond activation and formation of a rectangular tetradibenzotetraaza[14]annulene

Khaledi H, Olmstead MM, Fukuda T, Ali HM

Inorg Chem, 2014 Nov 3;53(21):11348-50.
PMID: 25320842 DOI: 10.1021/ic5019828

Three isomeric 2[Pd(II)-Ni(II)] metal complexes, derived from indoleninyl meso-substituted dibenzotetraaza[14]annulene, were synthesized. The resulting dimers feature Ni···Ni or, alternatively, Ni···π interactions in staggered or slipped cofacial structures. A remarkable insertion of palladium into two different C-H bonds yielded a 4[Pd(II)-Ni(II)] rectangular complex with dimensions of 8.73 × 10.38 Å.
Nanofork for single cells adhesion measurement via ESEM-nanomanipulator system

Ahmad MR, Nakajima M, Kojima M, Kojima S, Homma M, Fukuda T

IEEE Trans Nanobioscience, 2012 Mar;11(1):70-8.
PMID: 22275723 DOI: 10.1109/TNB.2011.2179809

In this paper, single cells adhesion force was measured using a nanofork. The nanofork was used to pick up a single cell on a line array substrate inside an environmental scanning electron microscope (ESEM). The line array substrate was used to provide small gaps between the single cells and the substrate. Therefore, the nanofork could be inserted through these gaps in order to successfully pick up a single cell. Adhesion force was measured during the cell pick-up process from the deflection of the cantilever beam. The nanofork was fabricated using focused ion beam (FIB) etching process while the line array substrate was fabricated using nanoimprinting technology. As to investigate the effect of contact area on the strength of the adhesion force, two sizes of gap distance of line array substrate were used, i.e., 1 μm and 2 μm. Results showed that cells attached on the 1 μm gap line array substrate required more force to be released as compared to the cells attached on the 1 μm gap line array substrate.
Fulltext Application of Environmental Scanning Electron Microscope-Nanomanipulation System on Spheroplast Yeast Cells Surface Observation

Rad MA, Ahmad MR, Nakajima M, Kojima S, Homma M, Fukuda T

Scanning, 2017;2017:8393578.
PMID: 29109826 DOI: 10.1155/2017/8393578

The preparation and observations of spheroplast W303 cells are described with Environmental Scanning Electron Microscope (ESEM). The spheroplasting conversion was successfully confirmed qualitatively, by the evaluation of the morphological change between the normal W303 cells and the spheroplast W303 cells, and quantitatively, by determining the spheroplast conversion percentage based on the OD800 absorbance data. From the optical microscope observations as expected, the normal cells had an oval shape whereas spheroplast cells resemble a spherical shape. This was also confirmed under four different mediums, that is, yeast peptone-dextrose (YPD), sterile water, sorbitol-EDTA-sodium citrate buffer (SCE), and sorbitol-Tris-Hcl-CaCl2 (CaS). It was also observed that the SCE and CaS mediums had a higher number of spheroplast cells as compared to the YPD and sterile water mediums. The OD800 absorbance data also showed that the whole W303 cells were fully converted to the spheroplast cells after about 15 minutes. The observations of the normal and the spheroplast W303 cells were then performed under an environmental scanning electron microscope (ESEM). The normal cells showed a smooth cell surface whereas the spheroplast cells had a bleb-like surface after the loss of its integrity when removing the cell wall.
Identification of de novo CSNK2A1 and CSNK2B variants in cases of global developmental delay with seizures

Nakashima M, Tohyama J, Nakagawa E, Watanabe Y, Siew CG, Kwong CS, et al.

J Hum Genet, 2019 Apr;64(4):313-322.
PMID: 30655572 DOI: 10.1038/s10038-018-0559-z

Casein kinase 2 (CK2) is a serine threonine kinase ubiquitously expressed in eukaryotic cells and involved in various cellular processes. In recent studies, de novo variants in CSNK2A1 and CSNK2B, which encode the subunits of CK2, have been identified in individuals with intellectual disability syndrome. In this study, we describe four patients with neurodevelopmental disorders possessing de novo variants in CSNK2A1 or CSNK2B. Using whole-exome sequencing, we detected two de novo variants in CSNK2A1 in two unrelated Japanese patients, a novel variant c.571C>T, p.(Arg191*) and a recurrent variant c.593A>G, p.(Lys198Arg), and two novel de novo variants in CSNK2B in Japanese and Malaysian patients, c.494A>G, p.(His165Arg) and c.533_534insGT, p.(Pro179Tyrfs*49), respectively. All four patients showed mild to profound intellectual disabilities, developmental delays, and various types of seizures. This and previous studies have found a total of 20 CSNK2A1 variants in 28 individuals with syndromic intellectual disability. The hotspot variant c.593A>G, p.(Lys198Arg) was found in eight of 28 patients. Meanwhile, only five CSNK2B variants were identified in five individuals with neurodevelopmental disorders. We reviewed the previous literature to verify the phenotypic spectrum of CSNK2A1- and CSNK2B-related syndromes.
Fulltext Albumin domain mutants with enhanced Aβ binding capacity identified by phage display analysis for application in various peripheral Aβ elimination approaches of Alzheimer's disease treatment

Ishima Y, Mimono A, Tuan Giam Chuang V, Fukuda T, Kusumoto K, Okuhira K, et al.

IUBMB Life, 2020 04;72(4):641-651.
PMID: 31794135 DOI: 10.1002/iub.2203

Deposition of amyloid protein, particularly Aβ1-42 , is a major contributor to the onset of Alzheimer's disease (AD). However, almost no deposition of Aβ in the peripheral tissues could be found. Human serum albumin (HSA), the most abundant protein in the blood, has been reported to inhibit amyloid formation through binding Aβ, which is believed to play an important role in the peripheral clearance of Aβ. We identified the Aβ binding site on HSA and developed HSA mutants with high binding capacities for Aβ using a phage display method. HSA fragment 187-385 (Domain II) was found to exhibit the highest binding capacity for Aβ compared with the other two HSA fragments. To elucidate the sequence that forms the binding site for Aβ on Domain II, a random screening of Domain II display phage biopanning was constructed. A number of mutants with higher Aβ binding capacities than the wild type were identified. These mutants exhibited stronger scavenging abilities than the wild type, as revealed via in vitro equilibrium dialysis of Aβ experiments. These findings provide useful basic data for developing a safer alternative therapy than Aβ vaccines and for application in plasma exchange as well as extracorporeal dialysis.
Developing a New Region-Specific Preference-Based Measure in East and Southeast Asia

Shiroiwa T, Murata T, Ahn J, Li X, Nakamura R, Teerawattananon Y, et al.

Value Health Reg Issues, 2022 Nov;32:62-69.
PMID: 36099801 DOI: 10.1016/j.vhri.2022.07.002

OBJECTIVES: Almost all preference-based measures (PBMs) have been developed in Western countries, with none having been formulated in Asian countries. In this study, we construct a new generic PBM based on concept elicitation using interview surveys in East and Southeast Asian countries and qualitative analysis.
METHODS: This cross-sectional study included 225 adults recruited from 9 East and Southeast Asian countries or regions (Indonesia, Japan, Korea, mainland China, Malaysia, the Philippines, Singapore, Taiwan, and Thailand). Trained interviewers conducted semistructured interviews with 25 participants from the general population of each country/region. Qualitative data were analyzed using a content analysis approach. The selection of items was determined based on interview surveys and team member discussions. The description of items was considered based on a detailed qualitative analysis of the interview survey.
RESULTS: A new region-specific PBM-the Asia PBM 7 dimensions instrument-was designed. It reflects East and Southeast Asian values and comprises 7 items: pain, mental health, energy, mobility, work/school, interpersonal interactions, and burden to others.
CONCLUSIONS: The new region-specific instrument is one of the first PBMs developed in the context of non-Western countries. The Asia PBM 7 dimensions contains 7 items that address the core concepts of health-related quality of life that are deemed important based on East and Southeast Asian health concepts.