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991.
Seita Osawa Hisashi Kato Yuki Maeda Hisashi Takakura Junetsu Ogasawara Tetsuya Izawa 《International journal of molecular sciences》2021,22(2)
Controlling the differentiation potential of adipose-derived stem cells (ADSCs) is attracting attention as a new strategy for the prevention and treatment of obesity. Here, we aimed to observe the effect of exercise training (TR) and high-fat diet (HFD) on the metabolic profiles of ADSCs-derived adipocytes. The rats were divided into four groups: normal diet (ND)-fed control (ND-SED), ND-fed TR (ND-TR), HFD-fed control (HFD-SED), and HFD-fed TR (HFD-TR). After 9 weeks of intervention, ADSCs of epididymal and inguinal adipose tissues were differentiated into adipocytes. In the metabolome analysis of adipocytes after isoproterenol stimulation, 116 metabolites were detected. The principal component analysis demonstrated that ADSCs-derived adipocytes segregated into four clusters in each fat pad. Amino acid accumulation was greater in epididymal ADSCs-derived adipocytes of ND-TR and HFD-TR, but lower in inguinal ADSCs-derived adipocytes of ND-TR, than in the respective controls. HFD accumulated several metabolites including amino acids in inguinal ADSCs-derived adipocytes and more other metabolites in epididymal ones. Kyoto Encyclopedia of Genes and Genomes enrichment analysis revealed that TR mainly affected the pathways related to amino acid metabolism, except in inguinal ADSCs-derived adipocytes of HFD-TR rats. These findings provide a new way to understand the mechanisms underlying possible changes in the differentiation of ADSCs due to TR or HFD. 相似文献
992.
993.
Ryoma Goto Eisaku Nishida Shuichiro Kobayashi Makoto Aino Tasuku Ohno Yuki Iwamura Takeshi Kikuchi Jun-ichiro Hayashi Genta Yamamoto Masaki Asakura Akio Mitani 《International journal of molecular sciences》2021,22(4)
Gelatin methacryloyl (GelMA) is a versatile biomaterial that has been used in various biomedical fields. UV light is commonly used to photocrosslink such materials; however, its use has raised several biosafety concerns. We investigated the mechanical and biological properties of a visible-wavelength (VW)-light-crosslinked gelatin-based hydrogel to evaluate its viability as a scaffold for bone regeneration in bone-destructive disease treatment. Irgacure2959 or riboflavin was added as a photoinitiator to create GelMA solutions. GelMA solutions were poured into a mold and exposed to either UV or VW light. KUSA-A1 cell-laden GelMA hydrogels were crosslinked and then cultured. Mechanical characterization revealed that the stiffness range of GelMA–RF hydrogel was suitable for osteoblast differentiation. KUSA-A1 cells encapsulated in GelMA hydrogels photopolymerized with VW light displayed significantly higher cell viability than cells encapsulated in hydrogels photopolymerized with UV light. We also show that the expression of osteogenesis-related genes at a late stage of osteoblast differentiation in osteoblasts encapsulated in GelMA–RF hydrogel was markedly increased under osteoblast differentiation-inducing conditions. The GelMA–RF hydrogel served as an excellent scaffold for the encapsulation of osteoblasts. GelMA–RF hydrogel-encapsulated osteoblasts have the potential not only to help regenerate bone mass but also to treat complex bone defects associated with bone-destructive diseases such as periodontitis. 相似文献
994.
Norihisa Nishimura Kosuke Kaji Koh Kitagawa Yasuhiko Sawada Masanori Furukawa Takahiro Ozutsumi Yukihisa Fujinaga Yuki Tsuji Hiroaki Takaya Hideto Kawaratani Kei Moriya Tadashi Namisaki Takemi Akahane Hiroshi Fukui Hitoshi Yoshiji 《International journal of molecular sciences》2021,22(13)
Recent studies have suggested that an alteration in the gut microbiota and their products, particularly endotoxins derived from Gram-negative bacteria, may play a major role in the pathogenesis of liver diseases. Gut dysbiosis caused by a high-fat diet and alcohol consumption induces increased intestinal permeability, which means higher translocation of bacteria and their products and components, including endotoxins, the so-called “leaky gut”. Clinical studies have found that plasma endotoxin levels are elevated in patients with chronic liver diseases, including alcoholic liver disease and nonalcoholic liver disease. A decrease in commensal nonpathogenic bacteria including Ruminococaceae and Lactobacillus and an overgrowth of pathogenic bacteria such as Bacteroidaceae and Enterobacteriaceae are observed in cirrhotic patients. The decreased diversity of the gut microbiota in cirrhotic patients before liver transplantation is also related to a higher incidence of post-transplant infections and cognitive impairment. The exposure to endotoxins activates macrophages via Toll-like receptor 4 (TLR4), leading to a greater production of proinflammatory cytokines and chemokines including tumor necrosis factor-alpha, interleukin (IL)-6, and IL-8, which play key roles in the progression of liver diseases. TLR4 is a major receptor activated by the binding of endotoxins in macrophages, and its downstream signal induces proinflammatory cytokines. The expression of TLR4 is also observed in nonimmune cells in the liver, such as hepatic stellate cells, which play a crucial role in the progression of liver fibrosis that develops into hepatocarcinogenesis, suggesting the importance of the interaction between endotoxemia and TLR4 signaling as a target for preventing liver disease progression. In this review, we summarize the findings for the role of gut-derived endotoxemia underlying the progression of liver pathogenesis. 相似文献
995.
Takehito Sugasawa Seiko Ono Masato Yonamine Shin-ichiro Fujita Yuki Matsumoto Kai Aoki Takuro Nakano Shinsuke Tamai Yasuko Yoshida Yasushi Kawakami Kazuhiro Takekoshi 《International journal of molecular sciences》2021,22(11)
The prevalence of nonalcoholic fatty liver disease (NAFLD) has been rapidly increasing worldwide. A choline-deficient, L-amino acid-defined, high-fat diet (CDAHFD) has been used to create a mouse model of nonalcoholic steatohepatitis (NASH). There are some reports on the effects on mice of being fed a CDAHFD for long periods of 1 to 3 months. However, the effect of this diet over a short period is unknown. Therefore, we examined the effect of 1-week CDAHFD feeding on the mouse liver. Feeding a CDAHFD diet for only 1-week induced lipid droplet deposition in the liver with increasing activity of liver-derived enzymes in the plasma. On the other hand, it did not induce fibrosis or cirrhosis. Additionally, it was demonstrated that CDAHFD significantly impaired mitochondrial respiration with severe oxidative stress to the liver, which is associated with a decreasing mitochondrial DNA copy number and complex proteins. In the gene expression analysis of the liver, inflammatory and oxidative stress markers were significantly increased by CDAHFD. These results demonstrated that 1 week of feeding CDAHFD to mice induces steatohepatitis with mitochondrial dysfunction and severe oxidative stress, without fibrosis, which can partially mimic the early stage of NASH in humans. 相似文献
996.
Michael G. Appiah Eun Jeong Park Yuichi Akama Yuki Nakamori Eiji Kawamoto Arong Gaowa Motomu Shimaoka 《International journal of molecular sciences》2021,22(15)
Sepsis is a sustained systemic inflammatory condition involving multiple organ failures caused by dysregulated immune response to infections. Sepsis induces substantial changes in energy demands at the cellular level leading to metabolic reprogramming in immune cells and stromal cells. Although sepsis-associated organ dysfunction and mortality have been partly attributed to the initial acute hyperinflammation and immunosuppression precipitated by a dysfunction in innate and adaptive immune responses, the late mortality due to metabolic dysfunction and immune paralysis currently represent the major problem in clinics. It is becoming increasingly recognized that intertissue and/or intercellular metabolic crosstalk via endocrine factors modulates maintenance of homeostasis, and pathological events in sepsis and other inflammatory diseases. Exosomes have emerged as a novel means of intercellular communication in the regulation of cellular metabolism, owing to their capacity to transfer bioactive payloads such as proteins, lipids, and nucleic acids to their target cells. Recent evidence demonstrates transfer of intact metabolic intermediates from cancer-associated fibroblasts via exosomes to modify metabolic signaling in recipient cells and promote cancer progression. Here, we review the metabolic regulation of endothelial cells and immune cells in sepsis and highlight the role of exosomes as mediators of cellular metabolic signaling in sepsis. 相似文献
997.
Yuki Yagishita Mai Mihara Yoshiumi Kohno Masashi Shibata 《Journal of food science》2016,81(12):E2950-E2955
The photochromic properties of some naturally occurring 3‐deoxyanthocyanidin pigments were investigated in various nontoxic solvents. When luteolinidin, a representative 3‐deoxyanthocyanidin, was dissolved in a mixture of weakly acidic water and an organic solvent with a relative permittivity between 20 and 34, it was possible to repeatedly induce coloration via ultraviolet irradiation and decoloration under light‐shielded conditions. 1,3‐Butanediol and ethanol, which are approved for use in foods, cosmetics, and household goods, were found to be appropriate organic solvents for this process. In addition, we confirmed that other 3‐deoxyanthocyanidins, specifically apigeninidin and tricetinidin, which are commonly found in food grains and tea leaves, also exhibit photochromic properties. 相似文献
998.
Ryuichi Hodoshima Yoshikazu Ohura Yuki Nishiyama Akihiro Sakaki Soichiro Watanabe Shinya Kotosaka 《Advanced Robotics》2016,30(23):1467-1483
This paper reports the design of a new hexapod walking robot, ASURA I, inspired by the physical features of a harvestman’s behavior. ASURA I has a special mobile form with one compact body and much longer legs than conventional hexapod walking robots. This form enhances the walking performance of the robot on rocky or uneven terrain. Here, we present the design and analysis of the leg mechanism, body structure design, gait planning, and prototype development. The long legs (relative to the body) are managed by special parallel link mechanisms, which powerfully and effectively drive the leg joints. The leg mechanism is analyzed by its kinematics, singularity, and static characteristics. The leg length and weight of ASURA I is 1.3 m and 27 kg, respectively. The alternating tripod and wave gaits of ASURA I are successfully demonstrated in a series of walking experiments. 相似文献
999.
Flow cytometry can provide detailed information about protein expression on cell surface and is, therefore, widely used in clinical testing. However, owing to the limited sensitivity of fluorescence signals, detection of low-expression cell surface markers is challenging. The present report describes a DNA-mediated, on-membrane assembly of conjugated polymer nanoparticles (Pdots) that amplifies fluorescence signal from surface markers for sensitive detection via flow cytometry. Single-stranded DNA (ssDNA)-conjugated antibodies are first bound to cell surface markers, from which ssDNA-modified Pdots are sequentially assembled using DNA hybridization. The use of DNA as a linker enables the distance-controlled assembly of Pdots to prevent fluorescence quenching, whereas their on-membrane sequential assembly allows amplification of the fluorescence signal without reducing binding ability of antibodies. Thus, two rounds of Pdot assembly achieve 31-fold amplification of the fluorescence signal from CD19 on Nalm-6 cells, which is 125-fold brighter than that obtained using the conventional fluorescent dye-based method. Moreover, the sequential assembly of 22 nm Pdots shows 24-fold higher fluorescence than one-step labeling with 81 nm Pdots, suggesting the advantage of the sequential assembly strategy in avoiding steric hindrance. The proposed method is expected to contribute to the sensitive detection of low-expression surface markers for early and accurate diagnosis. 相似文献
1000.
Kimihiro Taguchi Yuki Ishino Tomoharu Tokunaga Takahisa Yamamoto 《Journal of the European Ceramic Society》2021,41(8):4567-4571
Rate-controlled sintering of 8 mol%Y2O3-doped ZrO2 (8YSZ) polycrystals was performed by rating the current limit of alternating current (AC) electric field during a flash event; this method promotes constant linear shrinkage of the green compact with respect to the sintering time. A power dissipation peak associated with the flash event was suppressed by setting the initial current limit at 100 mA; after AC current hits 100 mA, the current limit was rated to a maximum value of 1100?2000 mA to keep shrinkage rate constant. The power dissipation behavior during the current-rating process exhibited a characteristic inverted S-shaped curve as a function of time. 8YSZ polycrystal with a near-theoretical density of 5.97 g/cm3 and a grain size of approximately 3.4 μm was produced in AC electric field (150 V/cm at 1000 Hz) with a final maximum current limit of 1150 mA as a rectangular bulk style. 相似文献