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ABSTRACTThe fillers inside a polymer matrix should typically be self-assembled in both the horizontal and vertical directions to obtain 3-dimentional (3D) percolation pathways, whereby the fields of application can be expanded and the properties of organic-inorganic composite films improved. Conventional dielectrophoresis techniques can typically only drive fillers to self-assemble in only one direction. We have devised a one-step dielectrophoresis-driven approach that effectively induces fillers self-assembly along two orthogonal axes, which results in the formation of 3D interconnected T-shaped iron microstructures (3D-T CIP) inside a polymer matrix. This approach to carbonyl iron powder (CIP) embedded in a polymer matrix results in a linear structure along the thickness direction and a network structure on the top surface of the film. The fillers in the polymer were controlled to achieve orthogonal bidirectional self-assembly using an external alternating current (AC) electric field and a non-contact technique that did not lead to electrical breakdown. The process of 3D-T CIP formation was observed in real time using in situ observation methods with optical microscopy, and the quantity and quality of self-assembly were characterized using statistical and fractal analysis. The process of fillers self-assembly along the direction perpendicular to the electric field was explained by finite element analogue simulations, and the results indicated that the insulating polyethylene terephthalate (PET) film between the electrode and the CIP/prepolymer suspension was the key to the formation of the 3D-T CIP. In contrast to the traditional two-step method of fabricating sandwich-structured film, the fabricated 3D-T CIP film with 3D electrically conductive pathways can be applied as magnetic field sensor.

Introduction: Cell therapeutic clinical trials using fetal mesencephalic tissue provided a proof-of-concept for regenerative therapy in patients with Parkinson's disease. Postmortem studies of patients with fetal grafts revealed that α-synuclein+ Lewy body (LB)-like inclusions emerged in long-term transplantation and might worsen clinical outcomes even if the grafts survived and innervated in the recipients. Various studies aimed at addressing whether host-derived α-synuclein could be transferred to the grafted neurons to assess α-synuclein+ inclusion appearance in the grafts. However, determining whether α-synuclein in the grafted neurons has been propagated from the host is difficult due to the intrinsic α-synuclein expression. Methods: We induced midbrain dopaminergic (mDA) neurons from human induced pluripotent stem cells (hiPSCs) and transplanted them into the striatum of immunodeficient rats. The recombinant human α-synuclein preformed fibrils (PFFs) were inoculated into the cerebral cortex after transplantation of SNCA−/− hiPSC-derived mDA neural progenitors into the striatum of immunodeficient rats to evaluate the host-to-graft propagation of human α-synuclein PFFs. Additionally, we examined the incorporation of human α-synuclein PFFs into SNCA−/− hiPSC-derived mDA neurons using in vitro culture system. Results: We detected human α-synuclein-immunoreactivity in SNCA−/− hiPSC-derived mDA neurons that lacked endogenous α-synuclein expression in vitro. Additionally, we observed host-to-graft α-synuclein propagation into the grafted SNCA−/− hiPSC-derived mDA neurons. Conclusion: We have successfully proven that intracerebral inoculated α-synuclein PFFs are propagated and incorporated from the host into grafted SNCA−/− hiPSC-derived mDA neurons. Our results contribute toward the basic understanding of the molecular mechanisms related to LB-like α-synuclein deposit formation in grafted mDA neurons.

Abstract Amphipathic arginine-rich peptide, A2-17, exhibits moderate perturbation of lipid membranes and the highest cell penetration among its structural isomers. We investigated the direct cell-membrane penetration mechanism of the A2-17 peptide while focusing on structural flexibility. We designed conformationally constrained versions of A2-17, stapled (StpA2-17) and stitched (StchA2-17), whose α-helical conformations were stabilized by chemical crosslinking. Circular dichroism confirmed that StpA2-17 and StchA2-17 had higher α-helix content than A2-17 in aqueous solution. Upon liposome binding, only A2-17 exhibited a coil-to-helix transition. Confocal microscopy revealed that A2-17 had higher cell penetration efficiency than StpA2-17, whereas StchA2-17 remained on the cell membrane without cell penetration. Although the tryptophan fluorescence analysis suggested that A2-17 and its analogs had similar membrane-insertion positions between the interface and hydrophobic core, StchA2-17 exhibited a higher membrane affinity than A2-17 or StpA2-17. Atomic force microscopy demonstrated that A2-17 reduced the mechanical rigidity of liposomes to a greater extent than StpA2-17 and StchA2-17. Finally, electrophysiological analysis showed that A2-17 induced a higher charge influx through transient pores in a planer lipid bilayer than StpA2-17 and StchA2-17. These findings indicate that structural flexibility, which enables diverse conformations of A2-17, leads to a membrane perturbation mode that contributes to cell membrane penetration.

Abstract The N-terminal fragment of apolipoprotein A-I (apoA-I), comprising residues 1–83, contains three segments prone to aggregation: residues 14–22, 53–58, and 67–72. We previously demonstrated that residues 14–22 are critical in apoA-I fibril formation while residues 53–58 entropically drove the nucleation process. Here, we investigated the impact of amyloidogenic mutations (Δ60–71/VT, Δ70–72, and F71Y) located around residues 67–72 on fibril formation by the apoA-I 1–83 fragment. Thioflavin T fluorescence assay demonstrated that the Δ60–71/VT mutation significantly enhances both nucleation and fibril elongation rates, whereas the Δ70–72 and F71Y mutations had minimal effects. Circular dichroism measurements and microscopic observations revealed that all variant fragments formed straight fibrils, transitioning from random coils to β-sheet structures. Kinetic analysis demonstrated that primary nucleation is the dominant step in fibril formation, with fibril elongation reaching saturation at high protein concentrations. Thermodynamically, both nucleation and fibril elongation were enthalpically and entropically unfavorable in all apoA-I 1–83 variants, in which the entropic barrier of nucleation was almost eliminated for the Δ60–71/VT variant. Taken together, our results suggest the presence of new aggregation-prone segment in the Δ60–71/VT variant that promotes nucleation through entropic effects.

Abstract Background During the fifth wave of the coronavirus disease 2019 (COVID-19) pandemic in Japan, which took place between June and September 2021, a significant number of COVID-19 cases with deterioration occurred in unvaccinated individuals

Abstract Regulation of α-synuclein (αS) fibril formation is a potent therapeutic strategy for αS-related neurodegenerative disorders. αS, an intrinsically disordered 140-residue intraneural protein, comprises positively charged N-terminal, hydrophobic non-amyloid β component (NAC), and negatively charged C-terminal regions. Although mouse and human αS share 95% sequence identity, mouse αS forms amyloid fibrils faster than human αS. To evaluate the kinetic regulation of αS fibrillation, we examined the effects of mismatched residues in human and mouse αS on fibril formation and intramolecular interactions. Thioflavin T fluorescence assay using domain-swapped or C-terminal-truncated αS variants revealed that mouse αS exhibited higher nucleation and fibril elongation than human αS. In mouse αS, S87N substitution in the NAC region rather than A53T substitution is dominant for enhanced fibril formation. Fӧrester resonance energy transfer analysis demonstrated that the intramolecular interaction of the C-terminal region with the N-terminal and NAC regions observed in human αS is perturbed in mouse αS. In mouse αS, S87N substitution is responsible for the perturbed interaction. These results indicate that the interaction of the C-terminal region with the N-terminal and NAC regions suppresses αS fibril formation and that the human-to-mouse S87N substitution in the NAC region accelerates αS fibril formation by perturbing intramolecular interaction.

Deposition and accumulation of amyloid fibrils is a hallmark of a group of diseases called amyloidosis and neurodegenerative disorders. Although polypeptides potentially have a fibril-forming propensity, native proteins have evolved into proper functional conformations to avoid aggregation and fibril formation. Understanding the mechanism for regulation of fibril formation of native proteins provides clues for the rational design of molecules for inhibiting fibril formation. Although fibril formation is a complex multistep reaction, experimentally obtained fibril formation curves can be fitted with the Finke-Watzky (F-W) two-step model for homogeneous nucleation followed by autocatalytic fibril growth. The resultant F-W rate constants for nucleation and fibril formation provide information on the chemical kinetics of fibril formation. Using the F-W two-step model analysis, we investigated the physicochemical mechanisms of fibril formation of a Parkinson’s disease protein α-synuclein (αS) and a systemic amyloidosis protein apolipoprotein A-I (apoA-I). The results indicate that the C-terminal region of αS enthalpically and entropically suppresses nucleation through the intramolecular interaction with the N-terminal region and the intermolecular interaction with existing fibrils. In contrast, the nucleation of the N-terminal fragment of apoA-I is entropically driven likely due to dehydration of large hydrophobic segments in the molecule. Based on our recent findings, we discuss the similarity and difference of the fibril formation mechanisms of αS and the N-terminal fragment of apoA-I from the physicochemical viewpoints.

Exercise training has the potential for inducing enhancements in peripheral circulation, which can play important preventive and therapeutic roles in peripheral circulatory diseases. However, the relevant published studies show conflicting and inconclusive results. Furthermore, useful or optimum ambient temperature for this purpose has not yet been established. Therefore, we investigated the acute responses in peripheral circulation from exposure of healthy subjects to treadmill exercise under different ambient temperatures; A total of 12 young adult volunteers (males 6, females 6) randomly underwent three sessions of treadmill exercise for 30 min under three different ambient temperatures (10°C, 20°C, and 30°C), at a predetermined exercise intensity. Before and after the intervention, leg skin blood flow (SBF) was measured by laser Speckle flowgraphy and hand skin temperature (ST), by digital thermometry; After the cessation of treadmill exercise, compared to the corresponding baseline values, a significant increase in SBF was observed under all ambient temperature conditions (P [ J Adv Biotechnol Exp Ther 2023; 6(1.000): 222-230]

Simple ascending aortic replacement is the gold standard for emergency surgery in patients with type A acute aortic dissection (TA-AAD). Some patients require a second intervention because of the aortic arch expansion. Zone 0 thoracic endovascular aneurysm repair (TEVAR) is one such treatment alternative. Herein, we present a case with aortic valve replacement and regrafting of the ascending aorta after emergency ascending aortic replacement and elective zone 0 TEVAR for TA-AAD owing to acute heart failure caused by worsening aortic regurgitation. Because the proximal site of the endograft was detected outside the clamp site of the ascending aortic graft and was critically fractured, the entire ascending aortic graft was planned to be replaced with the reconstruction of the proximal portion of the stent. The proximal site of the stent graft was turned over after removing the frame and sutured at the proximal arch, which was finally anastomosed with a new ascending aortic graft to avoid endoleaks. The patient's post-operative course was uneventful, and computed tomography revealed no endoleak of the residual stent graft.

Abstract Aggregation of α-synuclein (α-syn) into amyloid fibrils is closely associated with Parkinson’s disease (PD). Familial mutations or posttranslational truncations in α-syn are known as risk factor for PD. Here, we examined the effects of the PD-related A30P or A53T point mutation and C-terminal 123–140 or 104–140 truncation on the aggregating property of α-syn based on the kinetic and thermodynamic analyses. Thioflavin T fluorescence measurements indicated that A53T, Δ123‒140, and Δ104–140 variants aggregated faster than WT α-syn, in which the A53T mutation markedly increases nucleation rate whereas the Δ123‒140 or Δ104‒140 truncation significantly increases both nucleation and fibril elongation rates. Ultracentrifugation and western blotting analyses demonstrated that these mutations or truncations promote the conversion of monomer to aggregated forms of α-syn. Analysis of the dependence of aggregation reaction of α-syn variants on the monomer concentration suggested that the A53T mutation enhances conversion of monomers to amyloid nuclei whereas the C-terminal truncations, especially the Δ104–140, enhance autocatalytic aggregation on existing fibrils. In addition, thermodynamic analysis of the kinetics of nucleation and fibril elongation of α-syn variants indicated that both nucleation and fibril elongation of WT α-syn are enthalpically and entropically unfavorable. Interestingly, the unfavorable activation enthalpy of nucleation greatly decreases for the A53T and becomes reversed in sign for the C-terminally truncated variants. Taken together, our results indicate that the A53T mutation and the C-terminal truncation enhance α-syn aggregation by reducing unfavorable activation enthalpy of nucleation, and the C-terminal truncation further triggers the autocatalytic fibril elongation on the fibril surfaces.

Abstract We previously developed an amphipathic arginine-rich peptide, A2-17, which has high ability to directly penetrate across cell membranes. To understand the mechanism of the efficient cell-penetrating ability of the A2-17 peptide, we designed three structural isomers of A2-17 having different values of the hydrophobic moment and compared their membrane interaction and direct cell penetration. Confocal fluorescence microscopy revealed that cell penetration efficiency of peptides tends to increase with their hydrophobic moment, in which A2-17 L14R/R15L, an A2-17 isomer with the highest hydrophobic moment, predominantly remains on plasma cell membranes. Consistently, Trp fluorescence analysis indicated the deepest insertion of A2-17 L14R/R15L into lipid membranes among all A2-17 isomers. Electrophysiological analysis showed that the duration and charge flux of peptide-induced pores in lipid membranes were prominent for A2-17 L14R/R15L, indicating the formation of stable membrane pores. Indeed, the A2-17 L14R/R15L peptide exhibited the strongest membrane damage to CHO-K1 cells. Atomic force microscopy quantitatively defined the peptide-induced membrane perturbation as the decrease in the stiffness of lipid vesicles, which was correlated with the hydrophobic moment of all A2-17 isomers. These results indicate that optimal membrane perturbation by amphipathic A2-17 peptide is critical for its efficient penetration into cells without inducing stabilized membrane pores.

In Japan, major mumps outbreaks still occur every 4–5 years because of low mumps vaccine coverage (30–40%) owing to the voluntary immunization program. Herein, to prepare for a regular immunization program, we aimed to reveal the nationwide and long-term molecular epidemiological trends of the mumps virus (MuV) in Japan. Additionally, we performed whole-genome sequencing (WGS) using next-generation sequencing to assess results from conventional genotyping using MuV sequences of the small-hydrophobic (SH) gene. We analyzed 1,064 SH gene sequences from mumps clinical samples and MuV isolates collected from 25 prefectures from 1986 to 2017. The results showed that six genotypes, namely B (110), F (1), G (900), H (3), J (41), and L (9) were identified, and the dominant genotypes changed every decade in Japan since the 1980s. Genotype G has been exclusively circulating since the early 2000s. Seven clades were identified for genotype G using SH sequence-based classification. To verify the results, we performed WGS on 77 representative isolates of genotype G using NGS and phylogenetically analyzed them. Five clades were identified with high bootstrap values and designated as Japanese clade (JPC)-1, -2, -3, -4, -5. JPC-1 and -3 accounted for over 80% of the total genotype G isolates (68.3 and 13.8%, respectively). Of these, JPC-2 and -5, were newly identified clades in Japan through this study. This is the first report describing the nationwide and long-term molecular epidemiology of MuV in Japan. The results provide information about Japanese domestic genotypes, which is essential for evaluating the mumps elimination progress in Japan after the forthcoming introduction of the mumps vaccine into Japan’s regular immunization program. Furthermore, the study shows that WGS analysis using NGS is more accurate than results obtained from conventional SH sequence-based classification and is a powerful tool for accurate molecular epidemiology studies.

The number of complaints regarding offensive odors from service industries, such as restaurants and garages, has recently increased. In this study, we aimed to develop an adsorbent for hydrogen sulfide gas derived from domestic wastewater and reveal the mechanisms of its removal. The adsorbent used for hydrogen sulfide gas removal was prepared by mixing coal fly ash and blast furnace cement with a mixing ratio of 87:13 by mass percentage. The optimum calcination temperature of the adsorbent was 700 °C to achieve a high removal performance for both dry and humid hydrogen sulfide gas. The X-ray absorption fine structure analysis revealed that hydrogen sulfide was removed on the adsorbent by oxidizing to sulfate. A pilot-scale experiment was conducted to evaluate the removal performance of hydrogen sulfide gas derived from domestic wastewater using the developed adsorbent. For a week, the average removal percentage of hydrogen sulfide gas derived from domestic wastewater remained at 99.1%. Therefore, the developed adsorbent for hydrogen sulfide gas is promising and cost-effective for promoting the recycling of coal fly ash. HIGHLIGHTS Adsorbent for H2S gas was prepared by mixing coal fly ash and blast furnace cement.; Adsorbent could remove both dry and humid H2S gas.; H2S was oxidized to sulfate and removed from the adsorbent.; Average removal percentage of H2S gas remained at 99.1%.; This study contributes to sustainable development goals in terms of coal fly ash recycling.;

We assessed concentration-dependent effects of halothane or isoflurane inhalation on the electrocardiographic and hemodynamic variables using a cross-over design in intact beagle dogs (n = 4). Elevation of inhaled halothane from 1.0% to 2.0% or isoflurane from 1.5% to 2.5% decreased the mean blood pressure and prolonged the QRS width without significantly altering the heart rate, PR interval or QT interval. However, the observed changes disappeared after regressions of both anesthetic conditions to their initial settings. These results indicate that hypotension-induced, reflex-mediated increase of sympathetic tone may have counterbalanced the direct negative chronotropic, dromotropic and repolarization slowing effects of the anesthetics.

We compared dl-sotalol-induced electrocardiographic responses in intact dogs using a repeated-measures design among 1% halothane anesthesia, 1.5% isoflurane anesthesia with nitrous oxide (N2O), and conscious state to clarify influences of the anesthetics (n = 4). Basal PR interval was longer in halothane than either in isoflurane with N2O or in conscious state, reflecting sympathetic nerve suppression for the atrioventricular node by halothane. Both anesthetics exhibited longer basal QRS width than conscious state, suggesting their ventricular INa inhibition. Also, both anesthetics showed longer basal QT interval, QTcF and Tpeak-Tend than conscious state, indicating their ventricular IKr inhibition. Meanwhile, dl-sotalol prolonged PR interval similarly in isoflurane with N2O and in conscious state, which was less great in halothane, suggesting further sympathetic nerve suppression for the atrioventricular node might be limited in halothane. dl-Sotalol prolonged QT interval and QTcF >3 times greater in either of the anesthetics than in conscious state; moreover, dl-sotalol prolonged Tpeak-Tend similarly in both anesthetics, but hardly altered it in conscious state; indicating isoflurane with N2O as well as halothane may have reduced the repolarization reserve to increase the sensitivity of ventricle toward IKr suppression. Thus, isoflurane with nitrous oxide could be useful for in vivo IKr assay like halothane.

Amyloid fibrils represent a special type of protein aggregates that are currently receiving enormous attention due to their strong implication in molecular etiology of a wide range of human disorders. Amyloid fibrils represent highly ordered self-assemblies sharing a core cross-β-sheet structure. Such organization of the fibrils is responsible for amyloid insolubility and exceptional mechanical properties. The remarkable rigidity of the protein fibrillar aggregates is due to intra- and interstrand hydrogen bonds which stabilize the β-strand scaffold of amyloid fibrils. Increasing evidence indicates that physical properties of amyloid assemblies, especially their mechanical characteristics, play essential role in determining their cytotoxic action. This highlights the necessity of deciphering the correlation between the elastic properties of amyloid aggregates and their cytotoxicity. In the present paper we utilized the atomic force microscopy (AFM) to visualize and analyze the amyloid fibrils of G26R/W@8 mutant of N-terminal fragment of human apolipoprotein A-I (apoA-I). The examination of AFM images revealed the existence of two polymorphic forms of apoA-I fibrils – twisted ribbon and helical ribbon. The quantitative analysis of apoA-I elastic properties was performed within the framework of worm-like model of polymer chain using the Easyworm software. The Easyworm package analyzes the images of individual polymer chains obtained by the atomic force microscopy and allows calculation of the persistent length of a chain in three regimes depending on the ratio between the contour and persistent lengths of the polymer. The set of evaluated parameters included the Young’s modulus, persistent length, bending rigidity and the second moment of inertia. All parameters calculated for the helical ribbon conformation were higher than those of the twisted ribbon. These findings suggest that helical ribbon represents a more rigid and mechanically stable configuration. The results obtained may prove of importance for a deeper understanding the mechanics-driven pathological activities of amyloid fibrils.

The long-term safety of geological disposal of radioactive waste is studied through several simulations. Before underground disposal, radioactive waste is stored for 30 to 50 years at facilities near nuclear power plants to cool it down to around 100 degrees Celsius. It is then placed in steel canisters surrounded by artificial materials such as bentonite and concrete. To determine the long-term safety and stability of this disposal method, we’ve studied the corrosion rate of the steel canisters under different conditions using electro-chemical impedance spectroscopy (EIS). This paper describes the corrosion of the carbon steel and elucidates the corroded condition using EIS measurement. EIS was adopted to estimate the corrosion condition from the impedance frequency characteristic. In our experiment, samples of bentonite and carbon steel were Kunigel V1 compacted to 1.37 Mg/m3 dry density with several different water contents, and SM400 as a low carbon steel. An electric heater was set inside the steel canister to maintain the temperature at 100 degrees Celsius. This model was made to a scale of around 1/120 as a current concept of a vertical disposal plan and reproduced the enclosed situation after underground emplacement of the radioactive waste. During heating, we conducted EIS measurements and set this data result as an equivalent circuit. We noted some different trends of impedance frequency characteristic depending on the bentonite’s water content and the heating time. From this result, we estimated the corrosion condition to analyze the corrosion products.

We devised a reverse genetics system to generate an infectious human sapovirus (HuSaV) GII.3 virus. Capped/uncapped full-length RNAs derived from HuSaV GII.3 AK11 strain generated by in vitro transcription were used to transfect HuTu80 human duodenum carcinoma cells; infectious viruses were recovered from the capped RNA-transfected cells and passaged in the cells. Genome-wide analyses indicated no nucleotide sequence change in the virus genomes in the cell-culture supernatants recovered from the transfection or those from the subsequent infection. No virus growth was detected in the uncapped RNA-transfected cells, suggesting that the 5′-cap structure is essential for the virus’ generation and replication. Two types of virus particles were purified from the cell-culture supernatant. The complete particles were 39.2-nm-dia., at 1.350 g/cm3 density; the empty particles were 42.2-nm-dia. at 1.286 g/cm3. Two proteins (58-kDa p58 and 17-kDa p17) were detected from the purified particles; their molecular weight were similar to those of VP1 (~60-kDa) and VP2 (~16-kDa) of AK11 strain deduced from their amino acids (aa) sequences. Protein p58 interacted with HuSaV GII.3-VP1-specific antiserum, suggesting that p58 is HuSaV VP1. A total of 94 (57%) aa of p17 were identified by mass spectrometry; the sequences were identical to those of VP2, indicating that the p17 is the VP2 of AK11. Our new method produced infectious HuSaVs and demonstrated that VP2 is the minor protein of the virion, suggested to be involved in the HuSaV assembly.

The mutants of the tumor suppressor protein p53 form protein aggregates. It has been proposed that these aggregates propagate like prions, albeit the detailed mechanism of the propagation is unclear. Our recent study revealed that sulfated glycosaminoglycans, especially highly sulfated domains of heparan sulfate (heparan sulfate S-domains), participate in cancer pathology by mediating transcellular propagation of p53 aggregates.

Understanding the effect of uncertainties of Core Disruptive Accident (CDA) scenarios on debris bed coolability on a core catcher is required for decision making on design options to mitigate a CDA consequence. For the understanding, a huge number of calculations are required but are extremely difficult to perform because a huge number of calculations require much calculation time to solve non-steady equations in the coolability calculation model. Thus, we applied Artificial Neural Network (ANN), which is one of models for machine learning, to debris bed coolability calculations. The application of ANN is expected to exponentially improve the calculation speed of debris bed coolability because ANN provides results from experimental rules learned through training without solving non-steady equations. The application is in three steps. Firstly, we created many data for training ANN and validating the trained ANN through coolability calculations parameterizing main dominant inputs (particle diameter of debris bed, porosity of debris bed, etc.) by using Latin hypercube sampling. Secondly, ANN was trained and validated with the created data. The accuracy rate of the results by the ANN to the validation data exceeded 99%. In addition, the calculation time using ANN was micro seconds order. Finally, through demonstration calculations, it was confirmed that we can easily understand the effect of uncertainties of CDA scenarios on debris bed coolability owing to results visualization based on a huge number of parametric calculations using ANN. Thus, the application of ANN to debris bed coolability calculations should contribute to the decision making on design options to mitigate a CDA consequence.

Abstract Apolipoprotein A-I (apoA-I) undergoes a large conformational reorganization during remodeling of high-density lipoprotein (HDL) particles. To detect structural transition of apoA-I upon HDL formation, we developed novel monoclonal antibodies (mAbs). Splenocytes from BALB/c mice immunized with a recombinant human apoA-I, with or without conjugation with keyhole limpet hemocyanin, were fused with P3/NS1/1-Ag4-1 myeloma cells. After the HAT-selection and cloning, we established nine hybridoma clones secreting anti-apoA-I mAbs in which four mAbs recognize epitopes on the N-terminal half of apoA-I while the other five mAbs recognize the central region. ELISA and bio-layer interferometry measurements demonstrated that mAbs whose epitopes are within residues 1–43 or 44–65 obviously discriminate discoidal and spherical reconstituted HDL particles despite their great reactivities to lipid-free apoA-I and plasma HDL, suggesting the possibility of these mAbs to detect structural transition of apoA-I on HDL. Importantly, a helix-disrupting mutation of W50R into residues 44–65 restored the immunoreactivity of mAbs whose epitope being within residues 44–65 against reconstituted HDL particles, indicating that these mAbs specifically recognize the epitope region in a random coil state. These results encourage us to develop mAbs targeting epitopes in the N-terminal residues of apoA-I as useful probes for monitoring formation and remodeling of HDL particles.

Genotyping evidence that supports the interruption of endemic measles virus (MV) transmission is one of the essential criteria to be verified in achieving measles elimination. In Japan since 2014, MV genotype analyses have been performed for most of the measles cases in prefectural public health institutes nationwide. With this strong molecular epidemiological data, Japan was verified to have eliminated measles in March, 2015. However, even in the postelimination era, sporadic cases and small outbreaks of measles have been detected repeatedly in Japan. This study investigated the nationwide molecular epidemiology of MV between 2008 and 2017. The 891 strains in the total period between 2008 and 2017 belonged to seven genotypes (D5, D4, D9, H1, G3, B3, and D8) and 124 different MV sequence variants, based on the 450-nucleotide sequence region of the N gene (N450). The 311 MV strains in the postelimination era between 2015 and 2017 were classified into 1, 7, 8, and 32 different N450 sequence variants in D9, H1, B3, and D8 genotypes, respectively. Analysis of the detection period of the individual N450 sequence variants showed that the majority of MV strains were detected only for a short period. However, MV strains, MVs/Osaka.JPN/29.15/ [D8] and MVi/Hulu Langat.MYS/26.11/ [D8], which are named strains designated by World Health Organization (WHO), have been detected in many cases over 2 or 3 years between 2015 and 2017. The WHO-named strains have circulated worldwide, causing outbreaks in many countries. Epidemiological investigation revealed repeated importation of these WHO-named strains into Japan. To demonstrate the elimination status (interruption of endemic transmission) in situations with repeated importation of the same strains is challenging. Nevertheless, the detailed sequence analysis of individual MV strains and chronological analysis of these strains provided sufficient evidence to show that Japan has still maintained its measles elimination status in 2017.

Undifferentiated carcinoma of the pancreas (UDC) is rare and has a dismal prognosis. Here, we report a case of 6-year disease-free survival with a mixed type of UDC and UDC with osteoclast-like giant cells, with a high mitotic index as well as perineural, lymphatic, vessel, and diaphragmatic invasion. The patient underwent radical distal pancreatectomy and was subsequently treated with adjuvant chemotherapy using gemcitabine plus S-1 followed by maintenance chemotherapy with oral tegafur-uracil. The patient has been doing well with no evidence of recurrence for more than 6 years after surgery.

A 64-year-old man was found to have a nodule in his right lung. He also complained of nausea and abdominal pain during the clinical course. Esophagogastroduodenoscopy revealed a duodenal ulcer associated with severe stenosis and a suspicion of malignancy. However, three subsequent biopsies revealed no evidence of malignancy. The fourth biopsy showed scattered large eosinophilic cells with an eccentric nucleus, leading to a diagnosis of Russell body duodenitis (RBD). RBD is an extremely rare disease, and little is known about its etiology and clinical course. The pathogenesis of RBD is discussed based on our experience with this case.

An intelligent shRNA expression device (iRed) contains the minimum essential components needed for shRNA production in cells, and could be a novel tool to regulate target genes. However, general delivery carriers consisting of cationic polymers/lipids could impede function of a newly generated shRNA via electrostatic interaction in the cytoplasm. Recently, we found that faint electric treatment (fET) of cells enhanced delivery of siRNA and functional nucleic acids into the cytoplasm in the absence of delivery carriers. Here, we examined fET of cells stably expressing luciferase in the presence of iRed encoding anti-luciferase shRNA. Transfection of lipofectamine 2000 (LFN)/iRed lipoplexes showed an RNAi effect, but fET-mediated iRed transfection did not, likely because of the endosomal localization of iRed after delivery. However, fET in the presence of lysosomotropic agent chloroquine significantly improved the RNAi effect of iRed/fET to levels that were higher than those for the LFN/iRed lipoplexes. Furthermore, the amount of lipid droplets in adipocytes significantly decreased following fET with iRed against resistin in the presence of chloroquine. Thus, iRed could be a useful tool to regulate target genes following fET-mediated cytoplasmic delivery with endosomal escape devices.