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61.
The aim of the present study was to investigate the nature and prevalence of nonspecific somatic symptoms, pain and catastrophizing in children with Heritable Connective Tissue Disorders (HCTD), and to determine their association with disability. This observational, multicenter study included 127 children, aged 4–18 years, with Marfan syndrome (MFS) (59%), Loeys-Dietz syndrome (LDS) (8%), Ehlers-Danlos syndromes (EDS) (12%) and hypermobile Ehlers-Danlos syndrome (hEDS) (23%). The assessments included the Children's Somatization Inventory or parent proxy (CSI, PCSI), pain visual-analogue scale (VAS), SUPERKIDZ body diagram, Pain Catastrophizing Scale Child or parent proxy (PCS-C, PCS-P) and Childhood Health Assessment Questionnaire (CHAQ-30). Data from children aged ≥8 years were compared to normative data. In children ≥ 8 years (n = 90), pain was present in 59%, with a median of 4 (IQR = 3–9) pain areas. Compared to normative data, the HCTD group reported significantly higher on the CSI (p ≤ 0.001, d = 0.85), VAS pain intensity (p ≤ 0.001, d = 1.22) and CHAQ-30 (p ≤ 0.001, d = 1.16) and lower on the PCS-C (p = 0.017, d = −0.82) and PCS-P (p ≤ 0.001, d = −0.49). The intensity of nonspecific somatic symptoms and pain explained 45% of the variance in disability (r2 = 0.45 F(2,48) = 19.70, p ≤ 0.001). In children ≤ 7 years (n = 37), pain was present in 35% with a median of 5(IQR = 1–13) pain areas. The mean(SD) VAS scores for pain intensity was 1.5(2.9). Functional disability was moderately correlated to the number of pain areas (r = 0.56, p ≤ 0.001), intensity of nonspecific somatic symptoms (r = 0.63, p ≤ 0.001) and pain (r = 0.83, p ≤ 0.001). In conclusion, this study supports the need for comprehensive assessment of nonspecific somatic symptoms, pain, and disability in children with HCTD to allow tailored treatment.  相似文献   
62.
The effect of the surfactant dodecyl alkyl sulphate (C12AS) on the structure and function of lotic protistan assemblages was examined using the Experimental Stream Facility (ESF) operated by the Procter and Gamble Company. Population- and community-level responses to C12AS were monitored on introduced substrates placed in the channels 28 days prior to dosing (mature communities) as well as those placed in the channels on day 0 of dosing (immature communities), to allow for a broad assessment of the effect of the chemical on processes contributing both to community development and maintenance. C12AS appeared to elicit a subsidy response from the native protistan assemblage which may have resulted from both positive and negative responses at trophic levels above and below the assemblage. Protistan responses to the surfactant tended to occur more rapidly and be more sensitive than those documented for invertebrates and fish. C12AS elicited a modest response (i.e. a 20% change) from several reliable parameters including community respiration (reduced dissolved oxygen at 289 g per L), protozoan species richness (increased at 63 g per L) and protozoan community composition (increased dissimilarity at 1254 g per L). Responses to C12AS exceeded expected exposures in the real world by a factor of six or greater thereby indicating that the hazard of exposure to C12AS to stream communities is low. The results of this study support the use of mesocosms as decisive tools for evaluating the hazard posed by consumer product chemicals to natural communities and ecosystems  相似文献   
63.
Application of the small-fibre excitant and inflammatory irritant mustard oil or the excitatory amino-acid receptor agonist glutamate to the rat temporomandibular joint (TMJ) region evokes similar changes in jaw-muscle activity, suggesting that peripheral application of glutamate may be nociceptive. Application of mustard oil to the TMJ region is also inflammatory, but, it is not clear if application of glutamate is equally inflammatory. In this study the extent of plasma-protein extravasation and oedema induced by mustard oil application to the TMJ region was compared with that induced by glutamate. Application of mustard oil resulted in plasma-protein extravasation into the TMJ tissues and oedema of the TMJ region. In contrast, glutamate did not cause plasma-protein extravasation or oedema.  相似文献   
64.
Ischemic preconditioning has been shown to ameliorate injury due to subsequent ischemia in several organs. However, relatively little is known about preconditioning and the kidney. To address this, rats were randomized to control (C, N = 14), 2 min of ischemic preconditioning (P2 N = 10), 3 periods of 2 min of ischemia separated by 5 min periods of reflow (P2,3 N = 7), or three 5 min periods of ischemia separated by 5 min of reflow (P5,3 N = 6) prior to 45 min of bilateral renal ischemia followed by 24 hours of reperfusion. We observed a lower serum creatinine after 24 hours of reflow in P2, P2, 3 but not P5, 3 rats compared with C. Histology was examined in the C and P2, 3 groups and demonstrated less severe injury in the P2, 3 group. To gain insight into the mechanism by which preconditioning ameliorated ischemic injury, we performed near IR spectroscopy and 31P NMR spectroscopy. Based on near IR spectroscopy, the P2, 3 group had closer coupling of cytochrome aa3 redox state with that of hemoglobin during reflow. In the 31P NMR studies, the changes in ATP and pHi were similar during ischemia, but the P2, 3 group recovered ATP and pHi faster than C. These data suggest that ischemic preconditioning may ameliorate ischemic renal injury as assessed by functional, metabolic and morphological methods. The mechanism(s) by which this occurs requires additional study.  相似文献   
65.
Summary. The in vitro effects of piracetam treatment on the fluidity of membranes from the hippocampus of Alzheimer's Disease patients (AD) and non-demented controls were studied. Hippocampal membranes of AD patients showed a significant lower hydrocarbon core fluidity compared with membranes from elderly non-demented controls. Preincubation with piracetam enhanced the hydrocarbon core fluidity of hippocampal membranes from AD-patients as well as elderly controls in a concentration depending fashion, although the effect was more pronounced for the AD membranes. In the presence of piracetam, the difference of the membrane fluidity between AD and control membranes was not longer apparent. Received January 18, 1999; accepted April 13, 1999  相似文献   
66.
Impaired olfaction, hyposmia or anosmia are part of the clinical phenotype in neurodegenerative disorders including Alzheimer's disease (AD). It has been proposed that the most severely affected areas are interconnected with the central olfactory system in contrast to the relative sparing of other sensory areas which lack olfactory connections. The pathology of the first synaptic relay in the olfactory pathway, the olfactory bulb (OB), has been studied in AD, but the results have been inconsistent. In order to define more fully the pathology of the OB, we analysed 15 AD and 15 control cases, using amyloid and tau immunohistochemistry on serial sections. This study demonstrates for the first time that all layers of the OB are severely affected in AD and in normal ageing. The principal effector cells of the OB, the mitral cells, developed neurofibrillary tangles (NFTs) both in AD and in controls. All the cases, with the exception of two of the controls, contained NFTs. Amyloid immunoreactivity was detected in diffuse, primitive, classical and compact deposits in AD, while five control cases contained mainly diffuse deposits. We did not find a correlation between amyloid deposition and NFT formation. Among the control cases, two contained neither amyloid nor NFTs, eight had NFTs but no amyloid and only five had both NFTs and amyloid. All the AD cases had NFT and amyloid deposition. Our data suggest that the earlier pathology in the OB is NFT formation and more than ten NFTs/section is compatible with 93.3% diagnostic accuracy for AD.  相似文献   
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68.
Phospholipase A2 (PLA2) is a key enzyme in the metabolism of membrane phospholipids. PLA2 influences the processing and secretion of the amyloid precursor protein, which give rise to the -amyloid peptide, the major component of the amyloid plaque in Alzheimer's disease (AD). We investigated the PLA2 activity in two samples: in post-mortem brains from 23 patients with AD and 20 non-demented elderly controls, and platelets from 16 patients with a diagnosis of probable AD, 13 healthy controls and 14 elderly patients with a major depression. In AD brains PLA2 activity was significantly decreased in the parietal, and to a lesser degree in the frontal, cortex. Lower PLA2 activity correlated significantly with an earlier onset of the disease, an earlier age at death and higher counts of neurofibrillary tangles and senile plaques. In platelets PLA2 activity was also significantly reduced in the AD group as compared with healthy and depressed controls. The reduction of the enzyme activity in platelets correlated with an early disease onset and with the severity of cognitive impairment, indicating a relationship between abnormally low PLA2 activity and a more severe form of the illness. The present results provide new evidence for a disordered phospholipid metabolism in AD brains and suggest that reduced PLA2 activity may contribute to the production of amyloidogenic peptides in the disease. Further studies are needed to examine whether PLA2 activity in platelets may be useful as a peripheral marker for a subgroup of patients with AD.  相似文献   
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