296 research outputs found
Electron impact spectroscopy of some substituted oxiranes
Call number: LD2668 .T4 1962 W3
Effects of Murphy number on quadrupedal running gait based on a simple model
The 11th International Symposium on Adaptive Motion of Animals and Machines. Kobe University, Japan. 2023-06-06/09. Adaptive Motion of Animals and Machines Organizing Committee.Poster Session P4
Metallothionein contributes to neuropathic pain in partial sciatic nerve ligated rats
Neuropathic pain is a chronic pain state caused by nerve injury or diseases. The symptoms involve spontaneous pain, hyperalgesia and allodynia. Neuropathic pain develops by the mechanisms both central nervous system and peripheral nervous system. Moreover,both neuronal cells and glia cells are involved in the development of neuropathic pain. However, the pathogenic mechanism of neuropathic pain is not clearly understood. We previously reported that metallothionein lacked in peripheral nerve from patients of complex regional pain syndrome by proteomic approach. In this report, we examined whether the level of metallothionein (MT) is changed in partial sciatic nerve ligation (PSL) rats as the model animal of neuropathic pain and the administration of metallothionein affects behavior against physical and thermal stimulus to PSL rats. MT-I/II expression was gradually decreased in the distal region of the injury site. At day 28, MT-I/II expression was markedly decreased in both proximal and distal region at the same level. The administration of MT signifi cantly improved allodynia and thermal hyperalgesia comparing to the administration of PBS. Moreover,GAP43, a marker protein of nerve regeneration, increased in the distal region and g lial fibrillar acidic protein, a marker protein of infl ammation, decreased in the proximal region of the injury site. These results suggest that metallothionein is deeply related to occurrence of neuropathic pain and regeneration of the injured nerve in PSL rats.departmental bulletin pape
Production of anti-Candida antibodies in mice with gut colonization of Candida albicans.
BACKGROUND: Production of antibodies that are specific for allergens is an important pathological process in inflammatory allergic diseases. These contain the antibodies against antigens of Candida albicans, one of the normal microbial flora in an intestinal tract. We studied the effects of the prednisolone administration on the production of anti-Candida antibodies in the gastrointestinally C. albicans-colonized mice. METHODS AND MATERIALS: BALB/c mice, treated with antibacterial antibiotics to decontaminate indigenous intestinal bacterial flora, were inoculated intragastrically with C. albicans. The mice, in which C. albicans grows intestinally, were administered prednisolone to induce temporary immunosuppression. The Candida growth in their intestinal tract and their antibody response to Candida were examined. RESULTS: Antibiotic treatment allowed establishment of C. albicans gastrointestinal colonization, but did not cause subsequent systemic dissemination of C. albicans in all the animals. When these animals received an additional treatment with prednisolone, they showed a significantly higher population of C. albicans in their feces than those of animals treated with antibiotics alone, and the organisms were recovered even from their kidney. This systemic dissemination by C. albicans appeared to be temporal, because all the mice survived without any symptoms for more than 2 months. Examination of the serum titers of total immunoglobulin (Ig)E antibodies and specific IgE and IgG antibodies against Candida antigens demonstrated that titers of total IgE increased, partially by day 14 and clearly at day 27, in prednisolone-treated Candida-colonized mice. Without prednisolone treatment, an increment of the serum titer was scarcely observed. By day 27, corresponding to the increase of total IgE, the anti-Candida IgE and IgG titer increased in mice of the prednisolone-treated group. CONCLUSION: Administration of prednisolone to Candida-colonized mice can induce production of the IgG, IgE antibodies against Candida antigens, perhaps through temporal systemic dissemination of Candida from the intestinal tract
Zinc-dependent and independent actions of hydroxyhydroquinone
Coffee contains hydroxyhydroquinone (HHQ). HHQ is one of by-products released during bean roasting. Therefore, it is important to elucidate the bioactivity of HHQ to predict its beneficial or adverse effects on humans. We studied zinc-dependent and independent actions of commercially-procured synthetic HHQ in rat thymocytes using flow cytometric techniques with propidium iodide, FluoZin-3-AM, 5-chloromethylfluorescein diacetate, and annexin V-FITC. HHQ at 1050 μM elevated intracellular Zn2+ levels by releasing intracellular Zn2+. HHQ at 10 μM increased cellular thiol content in a Zinc-dependent manner. However, HHQ at 30–50 μM reduced cellular thiol content. Although the latter actions of HHQ (30–50 μM) were suggested to increase cell vulnerability to oxidative stress, HHQ at 0.3–100 μM significantly protected cells against oxidative stress induced by H2O2. The process of cell death induced by H2O2 was delayed by HHQ, although both H2O2 and HHQ increased the population of annexin V-positive living cells. However, HHQ at 10–30 μM promoted cell death induced by A23187, a calcium ionophore. HHQ at 10–30 μM exerted contrasting effects on cell death caused by oxidative stress and Ca2+ overload. Because HHQ is considered to possess diverse cellular actions, coffee with reduced amount of HHQ may be preferable to avoid potential adverse effects
Initial Stage of Molecular Adsorption on Si(100) and H-terminated Si(100) Investigated by UHV-STM(STM-Si(001))
We have investigated the initial stage of adsorption of a conjugated aromatic compound, 1, 4-bis[β-pyridyl-(2)-vinyl]benzene (P2VB), on the clean Si(100)-2×1 surface and the hydrogen terminated Si(100)-2×1-H surface by ultra-high-vacuum (UHV) scanning tunneling microscopy (STM). We found adsorbed molecules cannot migrate on the chemically active Si(100)-2×1 surface, while they can migrate on the chemically inactive hydrogen terminated Si(100)-2×1-H surface until they are trapped to hydrogen-missing dangling bonds. On the clean Si(100)-2×1, we observed four different adsorption directions. An individual molecule appears as two or three bright spots, the brightness and distance between bright spots varying for different cases. Through structural analysis and bias-voltage-dependent STM images, we conclude that the electronic states of Si dimers modulated by the adsorbed molecules are observed instead of the molecules themselves. A simple estimation by considering only the molecular size and shape reproduces the distribution of four different kinds of adsorption structures we observed
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