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Emergent centrality in rank-based supplanting process
Get PDFapplication/pdfWe propose a stochastic process of interacting many agents, which is inspired by rank-based supplanting dynamics commonly observed in a group of Japanese macaques. In order to characterize the breaking of permutation symmetry with respect to agents' rank in the stochastic process, we introduce a rank-dependent quantity, overlap centrality, which quantifies how often a given agent overlaps with the other agents. We give a sufficient condition in a wide class of the models such that overlap centrality shows perfect correlation in terms of the agents' rank in the zero-supplanting limit. We also discuss a singularity of the correlation in the case of interaction induced by a Potts energy.journal articl
Discovery and evaluating new drugs for babesiosis treatment
Get PDF帯広畜産大学博士（獣医学）2022application/pdf博士学位論文
大学院畜産学研究科 獣医学専攻
Doctoral Program of Veterinary Sciencedoctoral thesi
Lactose or milk oligosaccharide: which is significant among mammals?
Get PDFapplication/pdfImplications
・ α-Lactalbumin, a milk protein, had evolved from c-type lysozyme, and it can associate with β4-galactosyltransferase 1 within the mammary epithelial cells. The acceptor specificity of this enzyme had changed by result of the association of two proteins to biosynthesize lactose.
・ Milk oligosaccharides are biosynthesized in addition to lactose, as lactose is the preferred acceptor for several glycosyltransferases present within the cells.
・ Milk oligosaccharides can be utilized as significant energy sources for the suckling neonates of monotremes and marsupials even though the small intestinal mucosa of these neonates lacks a lactase.
・ Lactose has become a predominant saccharide in the milk of most eutherians, resulting from a hypothetical increase in the expression level of α-lactalbumin. It has become to be utilized as a significant energy source for the suckling neonates, as a result of the acquisition of lactase in the microvilli of small intestinal cells.
・ Human milk contains the oligosaccharides at significant concentrations along with lactose among eutherians, which should be advantageous for symbiosis with beneficial colonic bifidobacteria.journal articl
Glucocorticoid production and action in bovine luteinized granulosa cells
Get PDF帯広畜産大学Doctor of Agriculture博士（農学）2023application/pdfProgesterone (P4) and cortisol production and expression of luteinizing markers: pentraxin 3 (PTX3), regulators of G-protein signaling 2 (RGS2), and vanin 2 (VNN2), increase in luteinized granulosa cells (LGCs), but their relationship is not well established. Therefore, this study investigated the effects of P4 and cortisol on each other’s production and their effects on the expression of the above genes in cultured bovine LGCs. In chapter 3, the functional and morphological changes associated with luteinization of granulosa cells (GCs) and the mechanism of cortisol production were investigated. GCs were collected from follicles of 2–5 mm diameter and cultured in DMEM/F-12 supplemented with 10% fetal calf serum (FCS) for up to 14 Days. P4 production and expression of steroidogenic acute regulatory protein (STAR), cholesterol side-chain cleavage enzyme (CYP11A1), and 3β-hydroxysteroid dehydrogenase type 1 (HSD3B1) rapidly increased until Day 10 and stayed high thereafter. The expression of 21-hydroxylase (CYP21A2), one of the two enzymes required in the conversion of P4 into cortisol, was low and decreased further after 4 Days, whereas the expression of 11β-hydroxylase (CYP11B1), which is responsible for the final stage of cortisol production, was not detectable. Moreover, cortisol production from P4 was not detected, although high P4 production was observed during the culture period. On the other hand, the expression of 11β-hydroxysteroid dehydrogenase type 1 (HSD11B1), which converts cortisone to cortisol, dramatically increased on Day 2, decreased until Day 8, and stayed relatively constant thereafter. Cortisol production was only observed when cortisone, a substrate for HSD11B1, was added to the culture medium. Because the LGCs expressed receptors for adrenocorticotrophin hormone (ACTH) and angiotensin II (Ang II), which are major factors that stimulate cortisol in the adrenal cortex, the effects of these factors on cortisol production by the LGCs were investigated on Day 6 of culture. A 24-h treatment with ACTH or Ang II downregulated P4 production by the LGCs but did not affect the expression of CYP21A2, CYP11B1,or HSD11B1, and cortisol production was undetected. In Chapter 4, the effects of P4 on cortisol production and the expression of factors related to luteinization were investigated. LGCs were treated with trilostane (a P4 synthesis inhibitor), nomegestrol acetate (NA, a synthetic progestogen), or P4 for 24 h on Days 6 and 12 of the culture. Trilostane suppressed P4 production and STAR expression while elevating HSD11B1 and HSD3B1, PTX3, RGS2, and VNN2 expression and cortisol production. Concomitant treatments with NA or P4 dosedependently decreased cortisol production, HSD11B1, HSD3B1, PTX3, RGS2, and VNN2 expression but xii elevated STAR and HSD11B2 expression in both Day 6 and Day 12 LGCs. In Chapter 5, the effect of cortisol on P4 production and the expression of factors related to luteinization were examined. Cortisol increased HSD11B1, HSD3B1, PTX3, RGS2, and VNN2 expression while decreasing STAR and HSD11B2 without influencing P4 production. Altogether, these results indicate that: 1) bovine LGCs cannot produce cortisol using the locally produced P4 as a substrate but produce cortisol via the HSD11B1 pathway using the adrenal-sourced cortisone as a substrate; 2) progestogens suppress cortisol production by regulating HSD11B1 expression; and 3) progestogens and cortisol differentially regulate STAR, HSD3B1, HSD11B1, HSD11B2, PTX3, RGS2, and VNN2 expression in bovine LGCs. This suggests that both P4 and cortisol are produced by GCs during luteinization and that they regulate luteal function in an autocrine manner.⻩体化顆粒層細胞（LGC）においてprogesterone（P4）とcortisol，および⻩体化の指標であるpentraxin 3（PTX3），regulator of G protein signaling 2（RGS2）とvanin 2（VNN2）の発現はともに上昇するが，それらの関係性についてはよく分かっていない。そこで本研究ではP4 とcortisolが互いの⽣産に及ぼす影響と，これらのステロイドが上記の遺伝⼦発現に与える影響をウシLGCの培養系を⽤いて調べた。Chapter 3 ではウシ顆粒層細胞の⻩体化に伴う機能的，形態的変化とcortisol⽣産機序について調べた。直径2-5 mmの卵胞から吸引採取した顆粒層細胞を10%ウシ胎児⾎清を含むDMEM/F-12培養液で14⽇まで培養した。P4⽣産とそれに関与するsteroidogenic acute regulatory protein （STAR），cholesterol side-chain cleavage enzyme （CYP11A1），および 3β-hydroxysteroid dehydrogenase type 1 （HSD3B1）の発現は培養開始後10⽇まで増加し，その後⾼いレベルで推移した。P4 からcortisol への変換を仲介する２つの酵素のうち21-hydroxylase（CYP21A2）の発現は低く，4 ⽇以降にさらに低下した。Cortisol ⽣産の最終段階を担う11β -hydroxylase（CYP11B1）の発現は認められなかった。また培養期間中に⾼いP4 の⽣産が認められたにも関わらず，P4 からのcortisol ⽣産は認められなかった。⼀⽅でcortisone からcortisol への変換を仲介する11β-hydroxysteroid dehydrogenase type 1 （HSD11B1）の発現は2⽇⽬に顕著に増加した後，8⽇⽬にかけて減少し，その後はほぼ⼀定に保たれた。Cortisol⽣産はHSD11B1の基質であるcortisoneを培地中に加えた時のみに認められた。LGCで副腎⽪質においてcortisol合成を刺激する主要な因⼦であるACTH とangiotensin II（Ang II）の受容体の発現が認められたことから，これらの因⼦がLGC のcortisol ⽣産に与える影響を6 ⽇⽬のLGC を⽤いて調べた。ACTH，もしくはAng IIによる24時間の処置はLGCのP4⽣産を抑制したが，cortisol⽣産に関与するCYP21A2，CYP11B1，HSD11B1 のいずれの発現にも影響を与えなかった。Chapter 4 ではP4 がcortisol の⽣産および⻩体化関連因⼦発現に与える影響を調べた。6 ⽇⽬，もしくは12 ⽇⽬のLGC をtrilostane（P4合成阻害剤），nomegestrol acetate （NA，合成プロジェスタージェン），もしくはP4の存在下で24 時間培養した。Trilostane によりP4 ⽣産 阻害された結果HSD11B1，HSD3B1，PTX3，RGS2，および VNN2 の発現とcortisol の⽣産の増加が認められた ⼀⽅，STAR 発現の低下が認められた。NA もしくはP4 の同時添加は容量依存的にtrilostane の効果を低減させ，HSD11B1，HSD3B1，PTX3，RGS2，および VNN2 の発現とcortisol の⽣産を低下させ，STAR とHSD11B2の発現を増加させた。Chapter 5 ではcortisol がP4 の⽣産および⻩体化関連因⼦発現に与える影響を調べた。cortisol は容量依存的にHSD11B1，HSD3B1，PTX3， RGS2，および VNN2 の発現を増加させ，STAR とHSD11B2 の発現を低下させたが，P4 合成には影響を与えなかった。以上のことから，１）ウシLGC は局所で⽣産されるP4 を基質としたcortisol ⽣産は⾏えないが，副腎⽪質由来のcortisone を基質としたHSD11B1 によるcortisol ⽣産を⾏っていること，２）プロジェスタージェンはHSD11B1 の発現を抑えることで局所的なcortisolの⽣産を抑制すること，３）プロジェスタージェンとcortisolはSTAR，HSD3B1，HSD11B1，HSD11B2, PTX3，RGS2，および VNN2の発現を異なる⽅向に調節することが明らかになった。このことは⻩体化の過程でP4 とcortisol が共に顆粒層細胞で⽣産され、⾃⼰分泌的に⻩体機能の調節を⾏っていることを⽰唆するものである。博士学位論文大学院畜産学研究科 畜産科学専攻Doctoral Program of Animal Science and Agriculturedoctoral thesi
Tick-borne pathogens in camels: A systematic review and meta-analysis of the prevalence in dromedaries
Get PDFapplication/pdfPublished data on tick-borne pathogens (TBPs) in camels worldwide have been collected to provide an overview of the global prevalence and species diversity of camelid TBPs. Several TBPs have been detected in dromedary camels, raising concerns regarding their role as natural or maintenance hosts for tick-borne pathogens. Insubstantial evidence exists regarding the natural infection of camels with Babesia spp., Theileria spp., Anaplasma spp., and Ehrlichia spp., particularly because most of the camels were considered healthy at the time of sampling. Based on polymerase chain reaction (PCR) testing, a pooled prevalence of 35.3% (95% CI: 22.6–48.1%) was estimated for Anaplasma, which was the most frequently tested TBP in dromedaries, and DNA of Anaplasma marginale, Anaplasma centrale, Anaplasma ovis, Anaplasma platys, and A. platys-like were isolated, of which ruminants and dogs are reservoirs. Similarly, the estimated pooled prevalence for the two piroplasmid genera; Babesia and Theileria was approximately equal (10–12%) regardless of the detection method (microscopy or PCR testing). Nevertheless, Babesia caballi, Theileria equi, and Theileria annulata DNA have frequently been detected in camels but they have not yet been proven to be natural hosts. Scarce data detected Babesia microti, Anaplasma phagocytophilum, and Borrelia burgdorferi sensu lato (s.l.) DNA in blood of dromedaries, although ticks of the genus Ixodes are distributed in limited areas where dromedaries are raised. Interestingly, a pooled seroprevalence of 47.7% (26.3–69.2%) was estimated for Crimean–Congo hemorrhagic fever virus, and viral RNA was detected in dromedary blood; however, their contribution to maintain the viral transmission cycles requires further experimental investigation. The substantially low incidence and scarcity of data on Rickettsia and Ehrlichia species could imply that camels were accidentally infected. In contrast, camels may play a role in the spread of Coxiella burnetii, which is primarily transmitted through the inhalation of aerosols emitted by diseased animals and contaminated environments. Bactrian camels showed no symptoms due to the examined TBPs, meanwhile, clinical disease was seen in alpacas infected with A. phagocytophilum. Similar to dromedaries, accidental tick bites may be the cause of TBP DNA found in the blood of Bactrian camels. © 2023journal articl
Differences in daily milk production during early pregnancy alter placental characteristics and neonatal metabolic amino acid levels in dairy cows
Get PDFapplication/pdfWe investigated the effects of differences in milk production during early pregnancy on placental characteristics at full term, calf birth weights, and their metabolic status. Thirty-four Holstein cows were categorized into three groups (Low, n = 9; Middle, n = 16; High, n = 9) based on the quartile of average daily 4% fat-corrected milk production during early pregnancy. The High group showed higher milk component production than the other groups (P < 0.05) during early and mid-pregnancy. Although most placental characteristics did not differ significantly among the groups, cows in the High group had larger individual cotyledons and fewer medium-sized cotyledons than those in the Low group (P < 0.05). Plasma amino acid concentrations of calves in the Low and High groups were significantly higher than those of calves in the Middle group, although calf birth weights were similar among the groups. Furthermore, cows in the Low group had longer dry periods than those in the High (P = 0.004) and Middle (P = 0.058) groups. This suggests that cows in the Low group may have provided more amino acids to the fetus because of low lactation and long dry periods. Conversely, cows in the High group required more energy for lactation during early pregnancy, which can reduce nutrient availability to the placenta and fetus; however, increasing individual cotyledonary sizes during late pregnancy may ensure that the same amounts of amino acids as those in cows in the Low group are supplied to the fetus, recovering the birth weights. © 2023 by the Society for Reproduction and Development.journal articl
Campylobacter contamination of chicken meat in Japan : Geographical and Seasonal variations
Get PDFapplication/pdfChicken is a potent source of human Campylobacter infections. Hence, we investigated the prevalence and antimicrobial resistance of Campylobacter in 440 vacuum-packed chicken breast products during April–December 2021. Campylobacter was isolated from 174 samples (39.5%), in which the mean concentration of Campylobacter was 1.42 ± 0.65 log10 CFU/g, and 19.0% of the positive samples contained > 2.0 log10 CFU/g of Campylobacter. Campylobacter prevalence was significantly (P < 0.01) higher in Western Japan (64.2%) than in Eastern Japan (26.6%). The highest prevalence of Campylobacter in Western and Eastern Japan was observed in August (74.1%) and October (47.8%), respectively. A total of 149 Campylobacter jejuni and 37 C. coli isolates were obtained. C. coli was more frequent among Campylobacter isolated from Western Japan (29.1%) than those obtained from Eastern Japan (6.6%). Among all C. coli isolates, 73.0% and 37.8% were ciprofloxacin- and erythromycin-resistant, respectively. All C. jejuni isolates were susceptible to erythromycin. However, 42.3% of them were ciprofloxacin-resistant. Ciprofloxacin-resistant C. jejuni was significantly (P < 0.01) more frequently in isolates collected from Western Japan than in isolates obtained from Eastern Japan. This study revealed the geographical and seasonal variations in the prevalence of Campylobacter in chicken products. Chicken meat becomes contaminated with Campylobacter while slaughtering Campylobacter-infected broiler flocks in processing plants. Therefore, the development of efficient strategies for decreasing Campylobacter infection in broiler flocks in Western Japan should be prioritized to reduce human Campylobacter infections.journal articl
Prototheca 属４種を用いたマウス乳房炎モデルの病理学的解析
Get PDFapplication/pdfPrototheca 属は、クロレラ科の１属であり、植物表面、動物の消化管内、土壌、湖沼、汚水中などの湿潤環境に広く分布している。Prototheca 属は牛乳房炎の原因菌でもあり、P. bovis, P. ciferrii, P. blaschkeae を原因する乳房炎では乳房の腫脹、硬結、乳汁中の著しい凝塊、乳量低下などの症状がみられる。1990 年代以降Prototheca 属による牛乳房炎の報告は増加傾向にあり、日本を含む世界各国で確認されている。本研究では、異なるPrototheca 属４種の病原性に関する知見を得るために、免疫不全モデルマウスや健常な授乳期マウスの乳腺組織に各Prototheca 属を実験的に感染させて病理学的比較検討を行った。P.ciferrii とP. bovis、P. blaschkeae、P. vistulensis を実験に用いた。まず、未経産のSCID マウスに尾静脈から接種することで、血流感染におけるPrototheca 属の病原性と各臓器への親和性を病理学的に検討した。次に、授乳期のBALB/c マウス乳腺にPrototheca 属菌を乳頭口接種し、乳房での感染成立および乳飲みマウスへの経口的感染の有無を病理学的に検討した。SCID マウスへの感染実験の結果、P. bovis のみがマウスヘ感染性を示し、脳と腎組織に病変を形成した。乳腺組織へのP. bovis の血行性移行は認められなかった。授乳期BALB/c マウスに対する乳頭口接種では、P. bovis を接種した乳腺で肉眼的に褪色、腫脹、硬結感が認められ、組織学的に乳腺上皮細胞の消失と乳腺腔内で著しい増殖がみられた。P. ciferrii およびP. blaschkeae 接種乳腺では、肉眼的に乳腺組織の褪色が認められ、組織学的には菌の軽度増殖を伴う巣状の炎症がみられた。P. bovis、P. ciferrii およびP. blaschkeae はBALB/c マウスの泌乳期乳腺へ上行感染し、乳腺炎を引き起こした。牛乳房炎の原因菌としての報告が少ないことから病原性が不明であったP. ciferrii とP. blaschkeae は、少なくともマウス泌乳期乳腺組織に中等度炎症を引き起こすことがわかった。The genus Prototheca is a member of the family Chlorellaceae, and is widely distributed in moist environments such as the surfaces of plants, the digestive tracts of animals, soil, lakes, and sewage. Prototheca spp. is known to be a causative agent of bovine mastitis. Bovine mastitis affected by P. bovis, P. ciferrii and P. blaschkeae reveals swelling of the breast, induration, secretion of milk containing white flakes, and reduction in milk production. Since the 1990s, bovine mastitis caused by Prototheca spp. have been increasing, and is distributed in worldwide, including Japan. We experimentally infected immunocompromised mice and the mammary gland of healthy lactating mice with each Prototheca spp. to obtain knowledge on the pathogenicity of four different Prototheca spp. In this study, we used four different Prototheca spp., P. ciferrii, P. bovis, P. blaschkeae and P. vistulensis. Initially, the pathogenicity and organ tropism of Prototheca spp. in bloodstream infection were pathologically investigated by inoculating the SCID mice via the tail vein. Next, we inoculated the mammary glands of lactating BALB/c mice with Prototheca spp.by the teat orifice and examined pathologically for the establishment of the infection in the udder and oral transmission to the suckling mice. As a result of the experimental infection to SCID mice, only P. bovis showed infectivity in mice, and the pathological changes were observed in the brain and kidney. No blood-borne transfer of P. bovis to mammary tissue was observed. The mammary gland of lactating BALB/c mice, inoculated with P. bovis showed macroscopically discoloration, swelling, and hardening. Histopathology revealed loss of mammary gland epithelial cells and marked proliferation of organisms in the acinus. Mammary glands inoculated with P. ciferrii and P. blaschkeae showed macroscopically discoloration of mammary tissue and histologically focal inflammatory cell accumulations with mild organism proliferation. P. bovis, P. ciferrii and P. blaschkeae infected ascendingly in the lactating mammary glands of BALB/c mice. P. ciferrii and P. blaschkeae, whose virulency were unknown due to the few case reports of bovine mastitis, were found to infect the mammary gland of mice.departmental bulletin pape
鳥居龍蔵のセデック語語彙集（1901）への注釈
Get PDFapplication/pdf鳥居龍蔵は「台湾埔里社霧社蕃の言語（東部有黥面蕃語）」と題した論文を『東京人類学会雑誌』に三度寄稿し、セデック語パラン方言の語彙集を著した。そのうちの第一篇と第二篇は1900 年に出版されたものであり、これらにおけるセデック語の語彙についてはOchiai（2018）によって現代セデック語との比較の上で、注釈と分析がなされた。鳥居による第三篇は1901 年に出版されたものである。その内容は単語よりも句や節レベルの表現を中心にしている。それら表現は現代セデック語との隔たりが大きいため、Ochiai（2018）では考察の対象から外れた。ただし、本稿は第三篇も資料としての価値は第一篇・第二篇に劣らないと考える。そのため本稿では、現代セデック語とかけ離れた句や節の統語構造を扱うのではなく、それらを構成する単語レベルにおける注釈をOchiai（2018）に模して現代セデック語との比較の上で示し、Ochiai（2018）の正誤表も付す。departmental bulletin pape
