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Serum thyrotropin levels of natives in Sarawak, Borneo Island

Ogihara T, Yamamoto T, Fukuchi M, Oki K

J Clin Endocrinol Metab, 1972 Nov;35(5):711-5.
PMID: 5071341
Elucidation of Pyranonigrin Biosynthetic Pathway Reveals a Mode of Tetramic Acid, Fused γ-Pyrone, and exo-Methylene Formation

Yamamoto T, Tsunematsu Y, Noguchi H, Hotta K, Watanabe K

Org. Lett., 2015 Oct 16;17(20):4992-5.
PMID: 26414728 DOI: 10.1021/acs.orglett.5b02435

Successful activation of the pyranonigrin biosynthetic gene cluster and gene knockout in Aspergillus niger plus in vivo and in vitro assays led to isolation of six new products, including a spiro cyclobutane-containing dimeric compound, which served as the basis for the proposed comprehensive pyranonigrin biosynthetic pathway. Two redox enzymes are key to forming the characteristic fused γ-pyrone core, and a protease homologue performs the exo-methylene formation.
Fulltext Basics and recent advances of two dimensional- polyacrylamide gel electrophoresis

Magdeldin S, Enany S, Yoshida Y, Xu B, Zhang Y, Zureena Z, et al.

Clin Proteomics, 2014;11(1):16.
PMID: 24735559 DOI: 10.1186/1559-0275-11-16

Gel- based proteomics is one of the most versatile methods for fractionating protein complexes. Among these methods, two dimensional- polyacrylamide gel electrophoresis (2-DE) represents a mainstay orthogonal approach, which is popularly used to simultaneously fractionate, identify, and quantify proteins when coupled with mass spectrometric identification or other immunological tests. Although 2-DE was first introduced more than three decades ago, several challenges and limitations to its utility still exist. This review discusses the principles of 2-DE as well as both recent methodological advances and new applications.
Childhood cruelty to animals: a tri-national study

Mellor D, Yeow J, Mohd Hapidzal NF, Yamamoto T, Yokoyama A, Nobuzane Y

Child Psychiatry Hum Dev, 2009 Dec;40(4):527-41.
PMID: 19449100 DOI: 10.1007/s10578-009-0142-0

Childhood cruelty to animals is a symptom of conduct disorder that has been linked to the perpetration of violence in later life. Research has identified several factors associated with its etiology, including social factors. However, no cross-cultural studies on this phenomenon have been reported. This study investigated childhood cruelty to animals in Japan, Australia and Malaysia. Parents of 1,358 children between the ages of 5 and 13 years completed the Children's Attitudes and Behaviours towards Animals questionnaire (CABTA) which assesses Typical and Malicious Cruelty to animals. Analyses revealed no overall differences between children from these countries on either scale. However, younger boys were more likely to be cruel than younger girls in each country, and younger children in Australia and Japan were more likely to be cruel that older children in those countries. The findings are discussed in relation to previous research, and recommendations for future studies are suggested.
Fulltext Interstitial Axon Collaterals of Callosal Neurons Form Association Projections from the Primary Somatosensory to Motor Cortex in Mice

Oka Y, Doi M, Taniguchi M, Tiong SYX, Akiyama H, Yamamoto T, et al.

Cereb Cortex, 2021 10 01;31(11):5225-5238.
PMID: 34228058 DOI: 10.1093/cercor/bhab153

Association projections from cortical pyramidal neurons connect disparate intrahemispheric cortical areas, which are implicated in higher cortical functions. The underlying developmental processes of these association projections, especially the initial phase before reaching the target areas, remain unknown. To visualize developing axons of individual neurons with association projections in the mouse neocortex, we devised a sparse labeling method that combined in utero electroporation and confocal imaging of flattened and optically cleared cortices. Using the promoter of an established callosal neuron marker gene that was expressed in over 80% of L2/3 neurons in the primary somatosensory cortex (S1) that project to the primary motor cortex (M1), we found that an association projection of a single neuron was the longest among the interstitial collaterals that branched out in L5 from the earlier-extended callosal projection. Collaterals to M1 elongated primarily within the cortical gray matter with little branching before reaching the target. Our results suggest that dual-projection neurons in S1 make a significant fraction of the association projections to M1, supporting the directed guidance mechanism in long-range corticocortical circuit formation over random projections followed by specific pruning.
Fulltext Oxidative trans to cis Isomerization of Olefins in Polyketide Biosynthesis

Yamamoto T, Tsunematsu Y, Hara K, Suzuki T, Kishimoto S, Kawagishi H, et al.

Angew Chem Int Ed Engl, 2016 05 17;55(21):6207-10.
PMID: 27072782 DOI: 10.1002/anie.201600940

Geometric isomerization can expand the scope of biological activities of natural products. The observed chemical diversity among the pseurotin-type fungal secondary metabolites is in part generated by a trans to cis isomerization of an olefin. In vitro characterizations of pseurotin biosynthetic enzymes revealed that the glutathione S-transferase PsoE requires participation of the bifunctional C-methyltransferase/epoxidase PsoF to complete the trans to cis isomerization of the pathway intermediate presynerazol. The crystal structure of the PsoE/glutathione/presynerazol complex indicated stereospecific glutathione-presynerazol conjugate formation is the principal function of PsoE. Moreover, PsoF was identified to have an additional, unexpected oxidative isomerase activity, thus making it a trifunctional enzyme which is key to the complexity generation in pseurotin biosynthesis. Through the study, we identified a novel mechanism of accomplishing a seemingly simple trans to cis isomerization reaction.
Fulltext Acceptance and Preference for COVID-19 Vaccine among Japanese Residents at Early Stage of the Epidemic in Japan

Wu J, Cai G, Fan Y, Arima K, Lin Y, Wong L, et al.

Vaccines (Basel), 2023 Jan 11;11(1).
PMID: 36680002 DOI: 10.3390/vaccines11010157

Background: This study aimed to survey the attitudes toward COVID-19 vaccines and their acceptability among the Japanese public as soon as the United States Food and Drug Administration (FDA) authorized vaccines and their rollouts started around the world. Methods: An anonymous cross-sectional survey was conducted in Japan between 4 January and 5 March 2021. A questionnaire was administered to evaluate attitudes toward COVID-19 vaccines according to demographic characteristics, vaccine characteristics, and vaccine production. Results: A total of 1037 completed responses were received. More than half (63.5%) of the participants responded positively (extremely likely/likely) toward COVID-19 vaccines. The highest acceptance to be vaccinated was discovered among the youngest age group. As expected, participants who had never delayed acceptance or refused the vaccine in their history of vaccination had a significantly higher willingness to be vaccinated against COVID-19 (p < 0.001). Females (OR = 2.66, 95% CI: 1.99−3.58) and participants who had ever delayed acceptance or refuse the vaccine (OR = 3.49, 95% CI: 2.42−5.05) had higher odds of COVID-19 vaccine hesitancy. Participants with a postgraduate degree (OR = 0.64, 95% CI: 0.40−1.00) presented the highest willingness to be vaccinated against COVID-19. More than two-thirds (72.9%, 95% CI: 70.4%−75.8%) of the participants did not mind a booster dose required following primary vaccination. A total of 63.2% (95% CI: 60.0%−66.0%) of the participants only accepted a nearly 90% effective or above vaccine at preventing COVID-19. At the same, 86.4% (95% CI: 84.4%−88.4%) of the participants reported only accepting a vaccine with minor side effects. Conclusions: The moderate levels of COVID-19 vaccine acceptance found in the early phase of the pandemic demonstrate that it is important to improve the implementation of effective management for vaccine promotion and the acceptability of the vaccine to slow or delay transmission.
Fulltext Behavioural responses and anxiety symptoms during the coronavirus disease 2019 (COVID-19) pandemic in Japan: A large scale cross-sectional study

Cai G, Lin Y, Lu Y, He F, Morita K, Yamamoto T, et al.

J Psychiatr Res, 2021 Apr;136:296-305.
PMID: 33631655 DOI: 10.1016/j.jpsychires.2021.02.008

BACKGROUND: This study explored the behavioural responses and anxiety symptoms of the general adult population in Japan during the ongoing coronavirus disease 2019 (COVID-19) outbreak.
METHODS: A web-based cross-sectional survey was conducted between 12th and May 13, 2020. Quota sampling was used to attain equal gender and age distributions representative of the Japanese population.
RESULTS: A total of 4127 complete responses were analysed. Higher educational level (B = 0.045, p = 0.002) and household income (B = 0.04, p = 0.009) were associated with a higher increase in preventive measures when comparing before and after the state of emergency was declared. The highest reported social anxiety was a feeling of fear (65.6%), followed by embarrassment (43.8%), keeping infection a secret (41.3%), avoidance (41.3%), and stigma (25.5%). A total of 86.1% of the respondents reported moderate to severe anxiety. The partial least square-based structural equation modelling (PLS-SEM) revealed that being female has the greatest effect (B = 0.246, p
Fulltext Involvement of Lipocalin-like CghA in Decalin-Forming Stereoselective Intramolecular [4+2] Cycloaddition

Sato M, Yagishita F, Mino T, Uchiyama N, Patel A, Chooi YH, et al.

Chembiochem, 2015 Nov 2;16(16):2294-8.
PMID: 26360642 DOI: 10.1002/cbic.201500386

Understanding enzymatic Diels-Alder (DA) reactions that can form complex natural product scaffolds is of considerable interest. Sch 210972 1, a potential anti-HIV fungal natural product, contains a decalin core that is proposed to form through a DA reaction. We identified the gene cluster responsible for the biosynthesis of 1 and heterologously reconstituted the biosynthetic pathway in Aspergillus nidulans to characterize the enzymes involved. Most notably, deletion of cghA resulted in a loss of stereoselective decalin core formation, yielding both an endo (1) and a diastereomeric exo adduct of the proposed DA reaction. Complementation with cghA restored the sole formation of 1. Density functional theory computation of the proposed DA reaction provided a plausible explanation of the observed pattern of product formation. Based on our study, we propose that lipocalin-like CghA is responsible for the stereoselective intramolecular [4+2] cycloaddition that forms the decalin core of 1.
Fulltext Development and characterization of 27 microsatellite markers for the mangrove fern, Acrostichum aureum (Pteridaceae)

Yamamoto T, Tsuda Y, Mori GM, Cruz MV, Shinmura Y, Wee AK, et al.

Appl Plant Sci, 2016 Sep;4(9).
PMID: 27672519 DOI: 10.3732/apps.1600042

PREMISE OF THE STUDY: Twenty-seven nuclear microsatellite markers were developed for the mangrove fern, Acrostichum aureum (Pteridaceae), to investigate the genetic structure and demographic history of the only pantropical mangrove plant.
METHODS AND RESULTS: Fifty-six A. aureum individuals from three populations were sampled and genotyped to characterize the 27 loci. The number of alleles and expected heterozygosity ranged from one to 15 and 0.000 to 0.893, respectively. Across the 26 polymorphic loci, the Malaysian population showed much higher levels of polymorphism compared to the other two populations in Guam and Brazil. Cross-amplification tests in the other two species from the genus determined that seven and six loci were amplifiable in A. danaeifolium and A. speciosum, respectively.
CONCLUSIONS: The 26 polymorphic microsatellite markers will be useful for future studies investigating the genetic structure and demographic history of of A. aureum, which has the widest distributional range of all mangrove plants.