Fukushima University

The egg coat including mammalian zona pellucida (ZP) and the avian equivalent, i.e., inner- perivitelline layer (IPVL), is a specialized extracellular matrix being composed of the ZP gly- coproteins and surrounds both pre-ovulatory oocytes and ovulated egg cells in vertebrates. The egg coat is well known for its potential importance in both the reproduction and early development, although the underlying molecular mechanisms remain to be fully elucidated. Interestingly, ZP3, one of the ZP-glycoprotein family members forming scaffolds of the egg- coat matrices with other ZP glycoproteins, exhibits extreme but distinctive microheterogene- ity to form a large number of isoelectric-point isoforms at least in the chicken IPVL. In the present study, we performed three-dimensional confocal imaging and two-dimensional poly- acrylamide-gel electrophoresis (2D-PAGE) of chicken IPVLs that were isolated from the ovarian follicles at different growth stages before ovulation. The results suggest that the rel- ative proportions of the ZP3 isoforms are differentially altered during the structural matura- tion of the egg-coat matrices. Furthermore, tandem mass spectrometry (MS/MS) analyses and ZP1 binding assays against separated ZP3 isoforms demonstrated that each ZP3 iso- form contains characteristic modifications, and there are large differences among ZP3 iso- forms in the ZP1 binding affinities. These results suggest that the microheterogeneity of chicken ZP3 might be regulated to be associated with the formation of egg-coat matrices during the structural maturation of chicken IPVL. Our findings may provide new insights into molecular mechanisms of egg-coat assembly processes.

Although thermal ionization mass spectrometry (TIMS) has been employed for the high-precision analysis of isotope ratios, direct quantification of artificial mono-nuclide in the environment is difficult by even using isotope dilution (ID) due to the coexistence of the great magnitude of natural stable nuclides or isobars. In traditional TIMS and ID-TIMS, a sufficient amount of stable Sr doped on a filament is required to realize a stable and adequate ion-beam intensity (i.e., thermally ionized beams). However, the background noise (BGN) at m/z 90, detected by an electron multiplier, disturbs 90Sr analysis at low concentration levels due to peak tailing of a significant 88Sr ion beam dependent on the 88Sr-doping amount. Here, TIMS assisted by quadruple energy filtering was successfully employed for the direct quantification of attogram levels of an artificial monoisotopic radionuclide strontium-90 (90Sr) in microscale biosamples. Direct quantification was achieved by integrating the ID quantification of natural Sr and simultaneous 90Sr/86Sr isotope ratio analysis. Additionally, the measurement amount calculated by the combination of the ID and intercalibration was corrected for the net result amount of 90Sr by subtracting dark noise and the detected amount derived from the survived 88Sr, which are equivalent with the BGN intensity at m/z 90. Background correction revealed that the detection limits were in the range of 6.15 × 10-2-3.90 × 10-1 ag (0.31-1.95 μBq), depending on the concentration of natural Sr in a 1 μL sample, and the quantification of 0.98 ag (5.0 μBq) of 90Sr in 0-300 mg/L of natural Sr was successful. This method could analyze small sample quantities (1 μL), and the quantitative results were verified against authorized radiometric analysis techniques. Furthermore, the amount of 90Sr in actual teeth was successfully quantified. This method will be a powerful tool for measuring 90Sr in the measurement of micro-samples, which are required to assess and understand the degree of internal radiation exposure.

The purpose of this study is to discuss the actual condition of supply of the Fukushima Revitalization Rental Housing and current life state of residents in municipalities where evacuation orders were issued or cancelled. Residents of the Fukushima Revitalization Rental Housing are dissatisfied with their living environment and think that the communication environment should be improved although the Fukushima Revitalization Rental Housing plays an important role in the return of evacuees and the migration of new residents. This study points out that it is necessary to enrich support measures based on living conditions of returnees and migrants and to improve the living environment of residents as future issues.

The purpose of this study is to clarify the actual situation and their future issues of agricultural corporations in the 12 municipalities affected by Fukushima nuclear power plant accident. This study reveals that many agricultural corporations and local governments in the 12 municipalities recognize that securing and training human resources are important issues based on the results of a questionnaire survey targeting them. It points out that agricultural corporations need to establish the system to hire permanent and full-time employees, they need to improve their business conditions, and that they should consider to use the Local Vitalization Cooperator system.

The purpose of this study is to clarify the current situation and issues of local vitalization cooperators in 12 municipalities affected by Fukushima nuclear power plant accident. We conducted a questionnaire survey to local vitalization cooperators and local government officials in the 12 municipalities. Based on the results, we pointed out that it is necessary to improve the living environment, to provide learning opportunities to local vitalization cooperators and to provide support for business commencement and housing procurement.

The purpose of this study is to grasp the current situation and issues of local government officers in the areas affected by the nuclear disaster. Through this study, it became clear that the number of non-regular officers has increased after the nuclear accident and that only 30% of the regular officers had administrative experience before the accident. In addition, it also became clear that many of local government officers have still suffered from the damage caused by the accident, such as long-distance commuting and separation from their family members, and that they felt they had a lot of work to do. This study points out that it is necessary to enrich support for local government officers because local government officers were administrative subjects of revitalization as an issue.

The purpose of this study is to clarify the actual state and issues of non-profit private reconstruction support organizations in 12 municipalities affected by Fukushima nuclear accident, and to obtain knowledge on the ideal form of non-profit private reconstruction support organizations to promote revitalization from the nuclear disaster. Through a questionary survey targeted non-profit private reconstruction support organizations, it became clear that there were two problems: securing financial resources and human resources. In order to solve these two problems, it is necessary to consider measures to secure human resources by utilizing local vitalization cooperators system and to establish intermediate support organizations for non-profit private reconstruction support organizations of the 12 municipalities affected by Fukushima nuclear accident and Futaba County.

The purpose of this research is to clarify the actual situations and issues of the community development companies of eight municipalities of Futaba District of Fukushima Prefecture, and to present the issues to be resolved for revitalization of the areas affected by the nuclear disaster. Based on the results of a questionnaire survey conducted targeting the community development companies and municipalities of Futaba District, it is necessary for the community development companies and local governments to discuss and coordinate to solve the issues, and it is important for the community development companies to expand profitable businesses that contribute to securing independent financial resources.

In a convex grid drawing of a plane graph, all edges are drawn as straight-line segments without any edge-intersection, all vertices are put on grid points and all facial cycles are drawn as convex polygons. A plane graph G has a convex drawing if and only if G is internally triconnected, and an internally triconnected plane graph G has a convex grid drawing on an (n - 1) × (n - 1) grid if either G is triconnected or the triconnected component decomposition tree T (G) of G has two or three leaves, where n is the number of vertices in G. An internally triconnected plane graph G has a convex grid drawing on a 2n × 2n grid if T (G) has exactly four leaves. Furthermore, an internally triconnected plane graph G has a convex grid drawing on a 20n × 16n grid if T (G) has exactly five leaves. In this paper, we show that an internally triconnected plane graph G has a convex grid drawing on a 10n × 5n grid if T (G) has exactly five leaves. We also present a linear-time algorithm to find such a drawing.

Background Current therapeutic agents, including nifurtimox and benznidazole, are not sufficiently effective in the chronic phase of Trypanosoma cruzi infection and are accompanied by various side effects. In this study, 120 kinds of extracts from medicinal herbs used for Kampo formulations and 94 kinds of compounds isolated from medicinal herbs for Kampo formulations were screened for anti- T. cruzi activity in vitro and in vivo. Methods As an experimental method, a recombinant protozoan cloned strain expressing luciferase, namely Luc2-Tulahuen, was used in the experiments. The in vitro anti- T. cruzi activity on epimastigote, trypomastigote, and amastigote forms was assessed by measuring luminescence intensity after treatment with the Kampo extracts or compounds. In addition, the cytotoxicity of compounds was tested using mouse and human feeder cell lines. The in vivo anti- T. cruzi activity was measured by a murine acute infection model using intraperitoneal injection of trypomastigotes followed by live bioluminescence imaging. Results As a result, three protoberberine-type alkaloids, namely coptisine chloride, dehydrocorydaline nitrate, and palmatine chloride, showed strong anti- T. cruzi activities with low cytotoxicity. The IC 50 values of these compounds differed depending on the side chain, and the most effective compound, coptisine chloride, showed a significant effect in the acute infection model. Conclusions For these reasons, coptisine chloride is a hit compound that can be a potential candidate for anti-Chagas disease drugs. In addition, it was expected that there would be room for further improvement by modifying the side chains of the basic skeleton.

We experienced a case of tracheal adenoid cystic carcinoma that occupied approximately 90％ of the tracheal lumen. After a biopsy confirmed adenoid cystic carcinoma, tracheal ring resection and one-stage end-to-end anastomosis were performed. Laryngeal function was preserved, and the patient has not had a recurrence in the two years since the surgery. Although it depends on the conditions, tracheal ring resection and one-stage end-to-end anastomosis may be useful for simultaneously preserving laryngeal function and curing the disease.

Studies on the microorganisms used in food production are of interest because microbial genotypes are reflected in food qualities such as taste, flavor, and yield. However, several microbes are nonmodel organisms, and their analysis is often limited by the lack of genetic tools. Tetragenococcus halophilus, a halophilic lactic acid bacterium used in soy sauce fermentation starter culture, is one such microorganism. The lack of DNA transformation techniques for T. halophilus makes gene complementation and disruption assays difficult. Here, we report that the endogenous insertion sequence ISTeha4, belonging to the IS4 family, is translocated at an extremely high frequency in T. halophilus and causes insertional mutations at various loci. We developed a method named targeting spontaneous insertional mutations in genomes (TIMING), which combines high-frequency insertional mutations and efficient PCR screening, enabling the isolation of gene mutants of interest from a library. The method provides a reverse genetics and strain improvement tool, does not require the introduction of exogenous DNA constructs, and enables the analysis of nonmodel microorganisms lacking DNA transformation techniques. Our results highlight the important role of insertion sequences as a source of spontaneous mutagenesis and genetic diversity in bacteria. IMPORTANCE Genetic and strain improvement tools to manipulate a gene of interest are required for the nontransformable lactic acid bacterium Tetragenococcus halophilus. Here, we demonstrate that an endogenous transposable element, ISTeha4, is transposed into the host genome at an extremely high frequency. A genotype-based and non-genetically engineered screening system was constructed to isolate knockout mutants using this transposable element. The method described enables a better understanding of the genotype-phenotype relationship and serves as a tool to develop food-grade-appropriate mutants of T. halophilus.

Many irrigation ponds in Fukushima Prefecture were decontaminated due to the contamination of radiocesium released from Fukushima Daiichi Nuclear Power Plant. To evaluate the impact of decontamination on 137Cs dynamics in an urban pond in Koriyama City, Fukushima Prefecture, Japan, temporal changes in 137Cs concentrations in bottom sediments and pond water were investigated before and after bottom-sediment removal. Post-decontamination, 137Cs inventories in bottom sediments decreased by 46–89%. 137Cs inventories in bottom sediments were relatively high in fine sediments before decontamination, and were also high at points near the water inlet after decontamination. Following decontamination, the mean 137Cs concentration in suspended solids (SS) and the mean dissolved 137Cs concentration in pond water decreased by 52% and 5%, respectively. Even after decontamination, the normalized 137Cs concentrations in SS and in water, which were calculated by dividing the 137Cs concentrations by the mean 137Cs inventories in each area, were higher than those in rivers, dam reservoirs, and ponds elsewhere in Fukushima. The positive correlations between δ15N values, an indicator of the source contribution to bottom sediments, and 137Cs concentrations in the upper 5 cm of bottom sediments after decontamination implied that SS from urban areas gradually increased the 137Cs inventories in the pond. The results underline the importance of secondary inputs of 137Cs from highly urbanized catchments.

Red crown rot (RCR) is a soil-borne disease that damages soybean growth and decreases yield. Infected plants show earlier defoliation and pencil-like roots, sometimes resulting in mortality. This disease became common relatively recently, and information about its field-scale appearance is insufficient. Insufficient data is a major constraint when planning countermeasures. In this study, unmanned aerial vehicle (UAV)-acquired images were used to visualize the spatial and time series variation in the area damaged by RCR in the same farmer fields in 2018 and 2020. Field investigation showed that RCR severely damaged soybean production. The reductions of yield were estimated at 17.5% and 12.7% in 2018 and 2020, respectively. The visualized damage clarified the difference in the increasing rate and patterns of RCR between the 2 years. In 2018, the damaged area expanded along the planting row to the whole field, but in 2020, the expansion along the planting row was not great, and half of the fields remained sparsely damage. This difference implies that various factors are associated with damage occurrence and pathogen distribution. The method applied in this study is effective in visualizing RCR damage, but further improvement is required in the evaluation of intermediate damage and the generalization of the evaluation procedure.

Each element on the periodic table has its own unique peak spectrum in LIBS analysis. Therefore, the chemical composition of a sample can be determined by identifying the wavelength of each peak from the analyzed sample. This has been a common sample identification method. However, due to various measurement conditions and environments, this peak search with database reference is a very tedious task. In this study, we propose a new method of analyzing LIBS spectra using only standard samples and no database reference or peak wavelength search, based on a machine learning method.

The pyHomogeneity package is a pure python package for performing homogeneity tests. The homogeneity test is applied to detect one (or more) change-point/breakpoint in the time series or sequential data. It is one of the essential tests for time series data (e.g. financial time series, hydrology, climate study, etc.). However, till now, there is no Python package available for the homogeneity test. This is where the pyHomogeneity package comes in. Currently, Pettitt’s Test, four variants of Buishand’s Test, and SNHT Test can be performed using this package. The package is freely available for public use.

Zygentoma is an order of wingless insects, representing the sister group of Pterygota and constituting Dicondylia together with Pterygota. Contrasting views exist regarding midgut epithelium formation in Zygentoma. According to some reports, in Zygentoma, the midgut epithelium is entirely derived from yolk cells as in other wingless orders; however, according to other reports, the midgut epithelium is of dual origin in Zygentoma, similar to that in Palaeoptera of Pterygota, i.e., the anterior and posterior midgut epithelia are stomodaeal and proctodaeal respectively, whereas the middle part of the midgut originates from yolk cells. Aiming to provide a sound basis to evaluate the true image of midgut epithelium formation in Zygentoma, we examined the formation of the midgut epithelium in detail in Thermobia domestica, and concluded that the midgut epithelium is exclusively derived from yolk cells in Zygentoma, without the stomodaeal and proctodaeal elements involved in its formation. The participation of the anlagen differentiated at or around the stomodaeal and proctodaeal extremities in the formation of the midgut epithelium (bipolar formation) may be regarded as having first appeared not in Dicondylia but in Pterygota, of which the major part is represented by Neoptera with the midgut epithelium formed through bipolar formation.

As the determinants of yield products, rice panicle traits are important targets for breeding. Despite their importance in grain filling and subsequent yield productivity, knowledge on the organ distribution pattern in rice panicles is limited owing to the lack of objective evaluation methods. In this study, we developed a method for quantifying rice panicle organ distribution patterns. To validate our method for practical application in biology, we integrated this method into a quantitative trait locus (QTL) analysis and identified QTLs for panicle organ distribution patterns in rice. Interestingly, Grain number 1 ( Gn1 ), a major QTL of organ number, was not identified as a QTL for distribution pattern, indicating that the number and distribution of panicle organs are independently controlled. This study provides insight into rice panicle organ distribution patterns that will help improve breeding targeting rice panicle architecture.

The Fukushima Daiichi nuclear power plant accident happened after the devastating earthquake in the Pacific coastal area of Japan on 11 March 2011. After the accident, radioactive materials spread out over a wide area in Japan. Radioactive materials were retained on soil surfaces, causing environmental problems. Among the radioactive materials, cesium (137Cs) has a long half-life of 30.2 years, and it remains near the surface soil; therefore, it is necessary to remove soil contaminated by 137Cs. The contaminated soil layer of inhabited areas in Fukushima was already removed before April 2020. However, the remediation method of Cs with other radioactive materials needs further study, as the large quantity of contaminated soil is not easy to preserve. Electrokinetic (EK) treatment is one of the soil remediation technologies that utilizes EK phenomena at the interface between contaminated soils by transferring ions from the soil. We have developed a new type of EK method in which a cathode is placed on the surface of the soil and an anode is place inside the soil. By applying DC voltage in between the electrodes, the Cs ions can be removed from the contaminated soil. The removed Cs ions are gathered near to the cathode, and if the cathode can adsorb the Cs ions, then only the cathode needs to be preserved, solving the problem of storing a large amount of soil. We have been working to prepare a new type of cathode that can be effective in adsorbing Cs ions and at the same time easier to store and handle. We used natural zeolite and rice husk charcoal (kuntan) to prepare this electrode, which showed good potential for adsorbing Cs ions. The electrode showed flexibility, which is helpful for storing it in the same way as pasture rolls. However, the experiments were conducted in the laboratory with non-radioactive Cs; field experiments and observations are needed for practical applications of this method, as well as the new electrodes.