Changes and Possible Risk Factors in the Prevalence of Allergic Rhinitis among Children in Ulaanbaatar, Mongolia from 2009 to 2021

獨協医科大学博士（医学）令和5年度doctoral thesi

Subsurface structure identification at the blind prediction site of ESG6 based on the earthquake-to-microtremor ratio method and diffuse field concept for earthquakes

We participated in the blind prediction exercise organized by the committee of the blind prediction experiment during the 6th International Symposium on Effects of Surface Geology on Seismic Motion (CBP-ESG6). In response to the committee's request, we identified the ground velocity structure from microtremors observed at a target site as the first step of the exercise. First, we calculated the horizontal-to-vertical spectral ratio of microtremors (MHVR) at the target site from the distributed microtremor data collected in the vicinity of the target site in Kumamoto Prefecture. Then, we converted the MHVR into a pseudo horizontal-to-vertical spectral ratio of earthquake (pEHVR) using the previously proposed and validated earthquake-to-microtremor ratio (EMR) method, where an empirically obtained EMR is used to convert MHVR into pEHVR. Next, we inverted the S-wave and P-wave velocity structures based on the pEHVR and the diffuse field concept for earthquakes. The theoretical EHVR calculated from the identified velocity structure reproduced the pEHVR quite well in the frequency range of 0.1-22 Hz. After the collection of the blind prediction results by all the participants, the CBP-ESG6 released the observed earthquake records, a preferred model based on the P-S logging data from the in-situ borehole measurement combined with the generic deeper structure, and the average of all the predicted structures by the participants. Notably, our inverted structure was found to be close to the preferred model and the averaged one of all the blind prediction participants, despite some minor differences in the horizontal site amplification factor around the maximum peak frequency at 0.8-1 Hz

Isolating along-strike variations in the depth extent of shallow creep and fault locking on the northern Great Sumatran Fault

The Great Sumatran Fault system in Indonesia is a major right-lateral trench-parallel system that can be divided into several segments, most of which have ruptured within the last century. This study focuses on the northern portion of the fault system which contains a 200-km-long segment that has not experienced a major earthquake in at least 170 years. In 2005, we established the Aceh GPS Network for the Sumatran Fault System (AGNeSS) across this segment. AGNeSS observes large displacements which include significant postseismic deformation from recent large megathrust earthquakes as well as interseismic deformation due to continued elastic loading of both the megathrust and the strike slip system. We parameterize the displacements due to afterslip on the megathrust using a model based on a rate- and state-dependent friction formalism. Using this approach, we are able to separate afterslip from other contributions. We remove predicted deformation due to afterslip from the observations, and use these corrected time series to infer the depth of shallow aseismic creep and deeper locked segments for the Great Sumatran Fault. In the northern portion of this fault segment, we infer aseismic creep down to 7.3 ± 4.8 km depth at a rate of 2.0 ± 0.6 cm/year. In the southwestern portion of the segment, we estimate a locking depth of 14.8 ± 3.4 km with a downdip slip rate of 1.6 ± 0.6 cm/year. This portion of the fault is capable of producing a magnitude 7.0 earthquake

C‐Glycosyltransferases catalyzing the formation of di‐C‐glucosyl flavonoids in citrus plants

Citrus plants accumulate many kinds of flavonoids, including di‐C‐glucosyl flavonoids, which have attracted considerable attention due to their health benefits. However, the biosynthesis of di‐C‐glucosyl flavonoids has not been elucidated at the molecular level. Here, we identified the C‐glycosyltransferases (CGTs) FcCGT (UGT708G1) and CuCGT (UGT708G2) as the primary enzymes involved in the biosynthesis of di‐C‐glucosyl flavonoids in the citrus plants kumquat (Fortunella crassifolia) and satsuma mandarin (Citrus unshiu), respectively. The amino acid sequences of these CGTs were 98% identical, indicating that CGT genes are highly conserved in the citrus family. The recombinant enzymes FcCGT and CuCGT utilized 2‐hydroxyflavanones, dihydrochalcone, and their mono‐C‐glucosides as sugar acceptors and produced corresponding di‐C‐glucosides. The Km and kcat values of FcCGT toward phloretin were <0.5 μm and 12.0 sec−1, and those toward nothofagin (3ʹ‐C‐glucosylphloretin) were 14.4 μm and 5.3 sec−1, respectively; these values are comparable with those of other glycosyltransferases reported to date. Transcripts of both CGT genes were found to concentrate in various plant organs, and particularly in leaves. Our results suggest that di‐C‐glucosyl flavonoid biosynthesis proceeds via a single enzyme using either 2‐hydroxyflavanones or phloretin as a substrate in citrus plants. In addition, Escherichia coli cells expressing CGT genes were found to be capable of producing di‐C‐glucosyl flavonoids, which is promising for commercial production of these valuable compounds.ArticlePlant Journal.91(2):187-198(2017)journal articl

Changes and Possible Risk Factors in the Prevalence of Allergic Rhinitis among Children in Ulaanbaatar, Mongolia from 2009 to 2021

Background: The WHO Collaborating Center at Dokkyo Medical University conducted a survey in Ulaanbaatar in 2009 on the prevalence of pediatric asthma and allergic rhinitis (AR). We report on a follow-up survey done in 2021 to measure changes since 2009 and identify risk factors. Methods: Questionnaire based on International Study of Asthma and Allergies in Childhood with modifications was used in 2009 and 2021. The parent (s) of 200 boys and 200 girls, 6-7 years old, were randomly selected from and interviewed at the 10 clinic areas used in 2009. 50% were city districts and 50% were urban districts. Statistical data was analyzed using odds ratios analysis and chi-square testing. Results: Comparing 2009 and 2021, prevalence of AR decreased by 13.6%. In houses where there was exposure to tobacco smoke, AR decreased by 21.3% from 64.0% to 42.7%. In children with asthma, AR decreased by 9.8% from 25.8% to 16.0%. In children with respiratory infection when <1 year old, AR decreased by 7.9% from 41.8% to 33.9%. Conclusion: In comparing 2009 and 2021, the significance was greater between children with than without AR, with P < 0.001 for those exposed to tobacco smoke, and P < 0.005 for those with asthma. There was no significance for children with a history of respiratory infection when <1 year old. There was significance of exposure to tobacco smoke and having asthma as risk factors for AR but not for children with a history of respiratory infection when <1 year old.journal articl

Overexpression of the human MNB/DYRK1A gene induces formation of multinucleate cells through overduplication of the centrosome

BACKGROUND: Previously we cloned the human MNB/DYRK1A gene from the "Down syndrome critical region" on chromosome 21. This gene encodes a dual specificity protein kinase that catalyzes its autophosphorylation on serine/threonine and tyrosine residues. But, the functions of the MNB/DYRK1A gene in cellular processes are unknown. RESULTS: In this study, we examined HeLa cells transfected with cDNA encoding a green fluorescent protein (GFP)-MNB/DYRK1A fusion protein and found 2 patterns of expression: In one group of transfected cells, GFP-MNB/DYRK1A was localized as dots within the nucleus; and in the other group, it was overexpressed and had accumulated all over the nucleus. In the cells overexpressing GFP-MNB/DYRK1A, multinucleation was clearly observed; whereas in those with the nuclear dots, such aberrant nuclei were not found. Furthermore, in the latter cells, essential processes such as mitosis and cytokinesis occurred normally. Multinucleation was dependent on the kinase activity of MNB/DYRK1A, because it was not observed in cells overexpressing kinase activity-negative mutants, GFP-MNB/DYRK1A (K179R) and GFP-MNB/DYRK1A (Y310F/Y312F). Immunostaining of GFP-MNB/DYRK1A-overexpressing cells with specific antibodies against α- and γ-tubulin revealed that multiple copies of centrosomes and aberrant multipolar spindles were generated in these cells. CONCLUSIONS: These results indicate that overexpression of MNB/DYRK1A induces multinucleation in HeLa cells through overduplication of the centrosome during interphase and production of aberrant spindles and missegregation of chromosomes during mitosis

Comparative analysis of two glyceraldehyde-3-phosphate dehydrogenases from a thermoacidophilic archaeon, Sulfolobus tokodaii

AbstractSulfolobus tokodaii, a thermoacidophilic archaeon, possesses two structurally and functionally different enzymes that catalyze the oxidation of glyceraldehyde-3-phosphate (GAP): non-phosphorylating GAP dehydrogenase (St-GAPN) and phosphorylating GAP dehydrogenase (St-GAPDH). In contrast to previously characterized GAPN from Sulfolobus solfataricus, which exhibits V-type allosterism, St-GAPN showed K-type allosterism in which the positive cooperativity was abolished with concomitant activation by glucose 1-phosphate (G1P). St-GAPDH catalyzed the reversible oxidation of GAP to 1,3-bisphosphoglycerate (1,3-BPG) with high gluconeogenic activity, which was specific for NADPH, while both NAD+ and NADP+ were utilized in the glycolytic direction.Structured summary of protein interactionsGAPDH and GAPDH bind by molecular sieving (View interaction) GAPN and GAPN bind by 2.2molecular sieving (View interaction)