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71.
Noradrenergic deficits have been described in the hippocampus and the frontal cortex of Alzheimer's disease brains, which are secondary to locus coeruleus degeneration. Locus coeruleus is the brain stem nucleus responsible for synthesis of noradrenaline and from where all noradrenergic neurons project. In addition, it has been suggested that noradrenaline might play a role in modulating inflammatory responses in Alzheimer's disease. In this study we aimed to investigate the effect of various agonists and antagonists for adrenergic receptors on amyloid precursor protein processing. Among them, we found that prazosin, an α1-adrenoceptor antagonist, was able to reduce the generation of amyloid β in N2a cells. Treatment of transgenic APP23 mice with prazosin prevented memory deficits over time. Although prazosin did not influence amyloid plaque load, it induced astrocytic proliferation and increased the release of apolipoprotein E and anti-inflammatory cytokines. These findings suggest that chronic treatment with prazosin leads to an anti-inflammatory response with potential beneficial effects on cognitive performance.  相似文献   
72.
Purpose

There is consensus that Quality of Life (QOL) should be obtained through self-reports from people with intellectual Disability (ID). Thus far, there have been no attempts to collect self-reported QOL from people who are deaf and have ID.

Methods

Based on an established short measure for QOL (EUROHIS-QOL), an adapted easy-to-understand sign language interview was developed and applied in a population (n = 61) with severe-to-profound hearing loss and mild-to-profound ID. Self-reports were conducted at two time points (t1 and t2), 6 months apart. The Stark QOL, an established picture-based questionnaire, was also obtained at t2 and three Proxy ratings of QOL (from caregivers) were conducted for each participant at t1.

Results

Self-reported QOL was successfully administered at both time points for 44 individuals with mild and moderate ID (IQ reference age between 3.3 and 11.8 years).

The self-reports showed sufficient test–retest reliability and significant correlations with the Stark QOL. As anticipated, self-reported QOL was higher than proxy-reported QOL. Test–retest reliability and internal consistency were good for self-reported QOL.

Conclusion

Reliable and valid self-reports of QOL can be obtained from deaf adults with mild-moderate ID using standard inventories adapted to the linguistic and cognitive level of these individuals.

  相似文献   
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74.
Photoacoustic imaging (PAI) is a novel hybrid imaging technique that combines the advantages of optical and ultrasound imaging to produce hyperspectral images of the tissue. The feasibility of measuring oxygen saturation (sO2) with PAI has been demonstrated pre-clinically, but has limited use in humans under conditions of ischemia and reperfusion. As an important step towards making PAI clinically available, we present a study in which PAI was used to estimate the spatial distribution of sO2 in vivo during and after occlusion of the finger of eight healthy volunteers. The results were compared with a commercial oxygen saturation monitor based on diffuse reflectance spectroscopy. We here describe the capability of PAI to provide spatially resolved picture of the evolution of sO2 during ischemia following vascular occlusion of a finger, demonstrating the clinical viability of PAI as a non-invasive diagnostic tool for diseases indicated by impaired microvascularization.  相似文献   
75.
Ecotoxicology - The bottom sediments in catchment areas behind dams play a significant role in water ecosystems. On the other hand, the structure of sediments makes them a natural geosorbent, in...  相似文献   
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78.

Background

A complication of diabetes is neuropathy, a condition of sensory axon degeneration that originates in the epidermis. The mechanisms remain unknown but reactive oxygen species (ROS) have been implicated in this condition. In this study, we assessed the role of ROS and a candidate downstream target, MMP-13 in glucose-induced sensory axon degeneration in zebrafish and mice.

Methods

The effects of glucose on metabolism and sensory axon degeneration were assessed using qPCR and live imaging. ROS were analyzed using pentafluorobenzene-sulfonyl fluorescein and activation of the NF-κB stress response was determined using Tg(NF-κB:GFP) zebrafish. The role of MMP-13 and ROS in glucose-dependent axon degeneration was determined in zebrafish following treatment with the antioxidant, N-acetylcysteine and the MMP-13 inhibitor, DB04760. Neuropathic mice fed on a high-fat/high-sugar diet were treated with the MMP-13 inhibitor, CL-82198 to assess sensory recovery.

Results

Glucose treatment of zebrafish induced metabolic changes that resemble diabetes. Sensory axon degeneration was mediated by ROS-induced MMP-13 and prevented upon antioxidant treatment or MMP-13 inhibition. MMP-13 inhibition also reversed neuropathy in diabetic mice.

Conclusion

We demonstrate that zebrafish are suitable to study glucose-induced neurotoxicity. Given the effects in zebrafish and mice, MMP-13 inhibition may be beneficial in the treatment of human diabetic neuropathy.  相似文献   
79.
The frequent association of thyroid and parathyroid disorders has been reported. Most commonly, hyperthyroidism may coexist with hypercalcemia, but the latter is successfully treated when euthyroidism is achieved. However, the concomitant hyperthyroidism with primary hyperparathyroidism is of a rare occurrence. Moreover, it may frequently go unrecognized. In this paper we report a case of a patient with hypercalcemia due to PTH--secreting parathyroid adenoma associated with hyperthyroidism due to toxic nodular goiter. This case demonstrates the dramatic outcome of those two coexisting disorders. We point out that in patients with primary hyperparathyroidism thyroid function test should always be carried out. A proper, first-line treatment of hyperthyroidism will prevent the deterioration of primary hyperparathyroidism course, and thus surgical parathyroid treatment may safely be introduced.  相似文献   
80.
Amiodarone is a highly effective antiarrhythmic agent used in life-threatening ventricular and supraventricular arrhythmias. Its long-term use may however lead to several adverse effects, including corneal deposits, liver and thyroid gland dysfunction, lung lesions, bone marrow injury, skin lesions, or neurological abnormalities. The article presents the case of a 56-year-old man with a history of a stroke, who after a few days of amiodarone therapy for an episode of atrial fibrillation was diagnosed with amiodarone-induced hyperthyroidism and interstitial pulmonary lesions. Clinical and laboratory symptoms of hyperthyroidism and radiographic signs of pulmonary involvement did not occur until several weeks after discontinuation of amiodarone therapy. Differential diagnosis of causes of hyperthyroidism and diseases causing nodular pulmonary lesions did not demonstrate any other pathologies. Empirical antibiotic therapy and administration of thiamazole and high doses of propranolol failed to improve the patient's clinical status. It was not until thiamazole was given in combination with glucocorticosteroids, when a slow relief of hyperthyroidism symptoms and resolution of radiographic pulmonary signs were observed. Based on the presented case, the risk of appearance of 2 serious concomitant adverse effects was demonstrated, even following a short-term amiodarone therapy. This paper also contains an overview of adverse effects which may be encountered during or after therapy with this effective antiarrhythmic agent. It was emphasized how important it is to select patients appropriately, and to monitor potential adverse effects during amiodarone therapy.  相似文献   
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