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101.
Shouhei Ueda Takatoshi Nakatani Masashi Fukumoto Kiyoshi Maruyama Tateo Itoh Shin‐ichi Usami 《Entomological Science》2020,23(2):216-226
The silver‐studded blue, Plebejus subsolanus, is widely distributed in the Russian Altai mountains, northeastern China, the Korean Peninsula, and the Japanese archipelago. In Japan, the species is distributed across wide elevation ranges from the lowlands of Hokkaido to the subalpine zone of Honshu. Current subspecies classification in Japan is as follows: ssp. iburiensis, occurring in lowland grasslands in Hokkaido; ssp. yaginus in lower mountain grasslands in Honshu; and ssp. yarigadakeanus in higher mountain grasslands in Honshu. The habitat of this species has been markedly reduced due to recent habitat destruction and land‐use changes. Here, we undertook phylogeographic analyses of two subspecies, ssp. yaginus and yarigadakeanus in the central mountainous regions of Japan, based on two mitochondrial gene sequences, in order to collect information for establishing effective conservation strategies. From 57 samples from the four mountain ranges, we obtained a haplotype network comprised of 12 haplotypes. Because of the haplotype network topology, the geographic distribution of haplotypes and the correspondence of haplotype divergence to subspecies taxonomy, we provisionally divided the haplotypes into three haplogroups: YR1 and YR2, which comprised ssp. yarigadakeanus, and YG, which comprised ssp. yaginus. Mitochondrial DNA genetic differentiation generally agreed with morphological subspecies classification. The haplotype network suggested that ssp. yarigadakeanus populations had multiple origins, and the subspecies character of “bright blue of the male's wings” was assumed to have evolved independently in each subalpine meadow. We found that P. subsolanus was genetically differentiated depending upon the elevation at each mountain region, suggesting that each haplogroup should be a conservation unit. 相似文献
102.
Takatoshi Itoh Yasuro Wada Takeo Nakanishi 《Bioscience, biotechnology, and biochemistry》2013,77(6):1083-1086
Differential thermal analysis (DTA) was used for study of milk protein denaturation. Protein solutions produced an endothermic peak of characteristic shape and temperature of peak minimum. The peak minimum is considered the coagulation temperature of the protein.The influence of pH and additives such as sugars and NaCl was clearly observed on the thermograms of β-lactoglobulin solution. Addition of κ-casein to β-lactoglobulin solution showed an inhibitory effect on the heat coagulation.Solid proteins produced two-stage exothermic peaks between 200°C and 400°C.DTA was a useful method in the study of heat denaturation and degradation of protein. 相似文献
103.
Takatoshi Kimura Chihiro Ishikawa Antonio Osorio-Lozada Karen T. Robins Makoto Hibi 《Bioscience, biotechnology, and biochemistry》2013,77(10):1772-1776
Rhodococcus rubropertinctus N82 possesses unique regiospecific hydroxylation activity in biotransformation of compounds. In this study, the ability of whole cells of the strain R. rubropertinctus N82 in biotransformation was studied. The hydroxylation activity resulted in transforming 6,7-dihydro-4H-thieno[3,2-c]-pyridine-5-carboxylic acid tert-butyl ester (LS1) into 2-hydroxy-6,7-dihydro-4H-thieno[3,2-c]-pyridine-5-carboxylic acid tert-butyl ester (LP1), a pharmaceutical intermediate. By optimizing conditions for the hydroxylating biotransformation using whole cells of R. rubropertinctus N82 as biocatalyst, 3.3?mM LP1 was successfully produced from 4?mM LS1 with a molar yield of 83%. Thus, effective method was newly developed to produce LP1, which is a synthetic intermediate of a platelet inhibitor active pharmaceutical ingredient drug, prasugrel. 相似文献
104.
A study has been made with the changes occurred in the milk casein during frozen storage. The flocculated protein formed during storage of frozen milk was resolved in 4 ~ 5 peaks in free-boundary electrophoretic pattern, using veronal buffer containing 7 m urea.The flocculated protein was mainly casein. It may be considered that portions of casein have undergone some modification or denaturation during the destabilization process.Significant increase has occurred in the relative proportion of β-casein in the casein remaining in supernatant after removal of flocculate, indicating that the partial fractionation of casein component occurred as a result of flocculation. 相似文献
105.
Takatoshi Ohkuri Tomonori Mishima Akira Monji Shigenobu Kanba Tadashi Ueda 《Protein science : a publication of the Protein Society》2013,22(4):467-474
Sugars, which function as osmolytes within cells, retard the amyloid fibril formation of the amyloidosis peptides and proteins. To examine the mechanism of this retardation in detail, we analyzed the effect of sugars (trehalose, sucrose, and glucose) on the polypeptide chains in 3Hmut Wil, which is formed by the mutation of three His residues in Wil mutant as a cause of amyloid light‐chain (AL) amyloidosis, at pH 2, a pH condition under which 3Hmut Wil was almost denatured. Sugars caused the folding of 3Hmut Wil so that its polypeptide chains adopted a native‐like rather than a denatured conformation, as suggested by tryptophan fluorescence, CD spectroscopy, and heteronuclear NMR. Furthermore, these sugars promoted the folding to a native‐like conformation according to the effect of preferential hydration rather than direct interaction. However, the type of sugar had no effect on the elongation of amyloid fibrils. Therefore, it was concluded that sugar affected the thermodynamic stability of 3Hmut Wil but not the elongation of amyloid fibrils. 相似文献
106.
Murase T Misawa K Minegishi Y Aoki M Ominami H Suzuki Y Shibuya Y Hase T 《American journal of physiology. Endocrinology and metabolism》2011,300(1):E122-E133
The prevalence of obesity is increasing globally, and obesity is a major risk factor for type 2 diabetes and cardiovascular disease. We investigated the effects of coffee polyphenols (CPP), which are abundant in coffee and consumed worldwide, on diet-induced body fat accumulation. C57BL/6J mice were fed either a control diet, a high-fat diet, or a high-fat diet supplemented with 0.5 to 1.0% CPP for 2-15 wk. Supplementation with CPP significantly reduced body weight gain, abdominal and liver fat accumulation, and infiltration of macrophages into adipose tissues. Energy expenditure evaluated by indirect calorimetry was significantly increased in CPP-fed mice. The mRNA levels of sterol regulatory element-binding protein (SREBP)-1c, acetyl-CoA carboxylase-1 and -2, stearoyl-CoA desaturase-1, and pyruvate dehydrogenase kinase-4 in the liver were significantly lower in CPP-fed mice than in high-fat control mice. Similarly, CPP suppressed the expression of these molecules in Hepa 1-6 cells, concomitant with an increase in microRNA-122. Structure-activity relationship studies of nine quinic acid derivatives isolated from CPP in Hepa 1-6 cells suggested that mono- or di-caffeoyl quinic acids (CQA) are active substances in the beneficial effects of CPP. Furthermore, CPP and 5-CQA decreased the nuclear active form of SREBP-1, acetyl-CoA carboxylase activity, and cellular malonyl-CoA levels. These findings indicate that CPP enhances energy metabolism and reduces lipogenesis by downregulating SREBP-1c and related molecules, which leads to the suppression of body fat accumulation. 相似文献
107.
Cytoskeleton dynamics during phototropin-dependent chloroplast photorelocation movement was analyzed in protonemal cells of
actin- and microtubule-visualized lines of Physcomitrella patens expressing GFP- or tdTomato-talin and GFP-tubulin. Using newly developed epi- and trans-microbeam irradiation systems that
permit fluorescence observation of the cell under blue microbeam irradiation inducing chloroplast relocation, it was revealed
that meshwork of actin filaments formed at the chloroplast-accumulating area both in the avoidance and accumulation movements.
The structure disappeared soon when blue microbeam was turned off, and it was not induced under red microbeam irradiation
that did not evoke chloroplast relocation movement. In contrast, no apparent change in microtubule organization was detected
during the movements. The actin meshwork was composed of short actin filaments distinct from the cytoplasmic long actin cables
and was present between the chloroplasts and plasma membrane. The short actin filaments emerged from around the chloroplast
periphery towards the center of chloroplast. Showing highly dynamic behavior, the chloroplast actin filaments (cp-actin filaments)
were rapidly organized into meshwork on the chloroplast surface facing plasma membrane. The actin filament configuration on
a chloroplast led to the formation of actin meshwork area in the cell as the chloroplasts arrived at and occupied the area.
After establishment of the meshwork, cp-actin filaments were still highly dynamic, showing appearance, disappearance, severing
and bundling of filaments. These results indicate that the cp-actin filaments have significant roles in the chloroplast movement
and positioning in the cell. 相似文献
108.
Selective expansion of foxp3-positive regulatory T cells and immunosuppression by suppressors of cytokine signaling 3-deficient dendritic cells 总被引:3,自引:0,他引:3
Matsumura Y Kobayashi T Ichiyama K Yoshida R Hashimoto M Takimoto T Tanaka K Chinen T Shichita T Wyss-Coray T Sato K Yoshimura A 《Journal of immunology (Baltimore, Md. : 1950)》2007,179(4):2170-2179
Dendritic cells (DCs) induce immunity and immunological tolerance as APCs. It has been shown that DCs secreting IL-10 induce IL-10(+) Tr1-type regulatory T (Treg) cells, whereas Foxp3-positive Treg cells are expanded from naive CD4(+) T cells by coculturing with mature DCs. However, the regulatory mechanism of expansion of Foxp3(+) Treg cells by DCs has not been clarified. In this study, we demonstrated that suppressors of cytokine signaling (SOCS)-3-deficient DCs have a strong potential as Foxp3(+) T cell-inducing tolerogenic DCs. SOCS3(-/-) DCs expressed lower levels of class II MHC, CD40, CD86, and IL-12 than wild-type (WT)-DCs both in vitro and in vivo, and showed constitutive activation of STAT3. Foxp3(-) effector T cells were predominantly expanded by the priming with WT-DCs, whereas Foxp3(+) Treg cells were selectively expanded by SOCS3(-/-) DCs. Adoptive transfer of SOCS3(-/-) DCs reduced the severity of experimental autoimmune encephalomyelitis. Foxp3(+) T cell expansion was blocked by anti-TGF-beta Ab, and SOCS3(-/-) DCs produced higher levels of TGF-beta than WT-DCs, suggesting that TGF-beta plays an essential role in the expansion of Foxp3(+) Treg cells. These results indicate an important role of SOCS3 in determining on immunity or tolerance by DCs. 相似文献
109.
Inagaki M Yokoyama TA Sawada K Duc VM Kanai G Lu J Kakuta T Saito A 《Journal of biotechnology》2007,132(1):57-64
A common approach to construct a bioartificial renal tubule system is to utilize renal tubular cells seeded in porous polymer membrane hollow fibers. We have reported that overgrowth of renal tubular cells was not beneficial for the transport and reabsorption functions of bioartificial tubules. Therefore, long-term maintenance of a confluent monolayer of cells in hollow fibers is essential and technically challenging. In this study, we examined whether MEK inhibitor, U0126, could maintain the monolayer of Lewis-lung cancer porcine kidney 1 (LLC-PK(1)) cells on polystyrene plates and in a dialysis module housing hollow fibers made of ethylene vinyl alcohol (EVAL). We also evaluated the leakage of urea nitrogen (UN) and creatinine (Cr) through the cell-lined hollow fibers, and reabsorption of glucose and sodium by the cells, comparing the U0126-treated cells with nontreated cells in the module. Treatment with 50micromol l(-1) U0126 prevented the overgrowth of cells cultured on polystyrene plates. Moreover, U0126-treatment reduced the leakage of UN, and increased the reabsorption of electrolytes in 65cm(2) modules. Scanning electron microscopy revealed that it also prevented the overconfluence of cells in modules. Therefore, application of U0126 is a potentially effective method to improve the performance of the device. 相似文献
110.