836 research outputs found

    Metal-Containing Poly(ionic liquid) Exhibiting Photogeneration of Coordination Network: Reversible Control of Viscoelasticity and Ionic Conductivity

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    The control of physical properties of soft matters via external stimuli is useful for various applications. Poly(ionic liquid)s are versatile liquid polymers exhibiting ionic conductivity, though the development of photoresponsive poly(ionic liquid)s is still limited. Here, we report the synthesis and properties of a photoreactive poly(ionic liquid) 1a consisting of a Ru sandwich complex [Ru(C5H5){C6H3(OC6H12CN)3}]+ and a polymeric anion -[-CH2–CH(SO2N–SO2CF3)-]n-. Upon UV photoirradiation, the liquid transformed into a rubbery elastomer 2a through the photochemical reaction of the cations. The resultant elastomer is a unique hybrid coordination polymer comprising a cationic coordination network and anionic covalent chains. The elastomer returned to 1a upon heating. The application of light and heat resulted in a coordination structure transformation that caused reversible changes in viscoelasticity and ionic conductivity. The liquid 1a was synthesized by polymerization of ionic liquid 1b containing an H2C═CHSO2N–SO2CF3 anion. UV photoirradiation transformed 1b into a viscous elastomer 2b consisting of a coordination network, though the elastomer changed into 1a upon heating via polymerization of the anion

    Vascular changes in the rat brain during chronic hypoxia in the presence and absence of hypercapnia.

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    Changes in brain vascularity in adult rats during adaptation to chronic normobaric hypoxia with or without elevated CO(2) were morphometrically investigated. Immunohistochemistry with anti-rat endothelial cell antigen (RECA-1) antibody was carried out for the vascular analysis. After the rats were subjected to hypoxia for 2 to 8 weeks (wks)(10 percent O(2) in N(2)), the total area of blood vessels was measured in 6 brain regions. After 2 wks of hypoxia, the blood vessel area was found to be significantly increased in the frontal cortex, striatum, hippocampus, thalamus, cerebellum, and medulla oblongata, by 44% , 96% , 65% , 50% , 102% and 97% , respectively. The ratio of large vessels with an area &#62; 500 micro m(2) was also increased in all brain regions. Hypoxic adaptation in brain vascularity did not change during 8 wks of hypoxia, and the hypoxia-induced levels measured in the vasculature returned to control levels 2 wks after the termination of hypoxia in areas of the brain other than the cortex and thalamus. In addition, hypoxia-induced changes in terms of the total vascular area and vessel size distribution were significantly inhibited by the elevation in CO(2), whereas chronic hypercapnia without hypoxia had no effect on brain vascularity. These findings suggested that adaptations in brain vascularity in response to hypoxia are rapidly induced, and there are regional differences in the reversibility of such vascular changes. Carbon dioxide is a potent suppressor of hypoxia-induced vascular changes, and may play an important role in vascular remodeling during the process of adaptation to chronic hypoxia.</p

    BPSD and care burden

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    Purpose : We investigated the cognitive function, behavioral and psychological symptoms of dementia (BPSD), and activities of daily living (ADLs) of elderly individuals admitted in care facilities. Moreover, the factors affecting the care burden experienced by facility staffs were examined. Method : 24 care facilities for elderly individuals participated in the study. The Revised Hasegawa Dementia Scale (HDS-R), Japanese version of the Neuropsychiatric Inventory (NPI), and Crichton Geriatric Behavioral Rating Scale (CGBRS) were used to evaluate cognitive function, BPSD, and ADL, respectively. The short Japanese version of the Zarit Burden Interview was used to assess the care burden. A multiple regression analysis was conducted with data obtained from 464 elderly individuals who fulfilled all the scales. Results : The care burden was correlated to the scores of HDS-R, but not with those of dysphoria/depression and disinhibition of NPI, restlessness of CGBRS, and subjective mood of CGBRS (R2 = 0.309, p < 0.005). Conclusion : Dysphoria/depression, disinhibition, restlessness, and subjective mood, but not cognitive decline, have an effect on the care burden experienced by facility staffs who manage elderly individuals. These results indicated that the appropriate diagnosis and treatment of BPSD are important in reducing the burden of facility staffs

    ニンチショウ ト エイヨウ

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    Japan has rapidly been becoming an aged society. Most of people are eager to grow older healthily. One of the most important things for aged people is how to prevent risks for dementia. It is well known that hypertention, hyperlipemia and diabetes are risk factors for vasucular dementia. Moreover recently it comes to be clear that diabetes increase the risk not only for vasucular dementia but also for Alzheimer’s disease. Mediterranean diet is well-known to prevent Alzheimer disease. A number of prospective epidemiologic studies have found association between nutrition and dementia. For example, n‐3fatty acid, vitamins and polyphenol may be associated with decrease of the risk for dementia. It may also be useful to prevent metabolic syndrome before aging. It is necessary for all to mind the relationship between diet and dementia

    Glucocorticoid Generates ROS to Induce Oxidative Injury in the Hippocampus, Leading to Impairment of Cognitive Function of Rats

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    The present study attempted to clarify whether over-secretion of glucocorticoids in the serum caused by increased hypothalamus-pituitary-adrenal activity induces oxidative stress in the rat brain, and how the stress causes the emergence of cognitive deficits. When rats were subcutaneously injected with corticosterone, lipid hydroperoxides and protein carbonyls increased markedly in the hippocampus in association with a decrease in activity of antioxidative enzymes, such as superoxide dismutase, catalase and glutathione peroxidase. These results suggest that high-level corticosterone in the serum induces reactive oxygen species (ROS), leading to oxidative damage in the hippocampus. After administration of corticosterone to rats, glucose and superoxide levels in the serum increased markedly. Furthermore, pyramidal cell apoptosis was observed to accompany the loss of glucocorticoid receptors at the cornus ammonis 1 region of the hippocampus. Rats injected with corticosterone showed marked deficits in memory function. The present results imply that ROS generated from the glycation reaction of increased glucose levels caused by gluconeogenesis activation through glucocorticoid with proteins in the serum attack the hippocampus to induce neurodegeneration, resulting in cognitive deficits in rats

    NIRS during cognitive tasks might predict drug response in OCD

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    Objective: We investigated oxyhemoglobin change in the prefrontal cortex (PFC) of patients with obsessive–compulsive disorder (OCD) who showed different responses to pharmacotherapy during neuropsychological tasks with near-infrared spectroscopy. Subjects and methods: A total of 42 patients with OCD (mean age: 35.6±9.6 years, 14 men, 28 women) and healthy control subjects (mean age: 35.4±9.7 years, 13 men, 29 women) were selected. Patients with OCD were divided into three groups (responders to selective serotonin-reuptake inhibitors (SSRIs), responders to SSRIs with antipsychotics, and nonresponders to SSRIs and SSRIs with antipsychotics) based on pharmacological response. We investigated oxyhemoglobin change in the PFC of subjects during Stroop tasks and a verbal fluency test with near-infrared spectroscopy. Results: Responders to SSRIs showed smaller activation compared to control subjects during the Stroop incongruent task and verbal fluency test, but not during the Stroop congruent task. In contrast, responders to SSRIs with antipsychotics showed smaller activation compared to control subjects during all three tasks. Conclusion: Our results suggest that activation of the PFC during Stroop tasks might predict responses to pharmacotherapy of patients with OCD
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