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991.
Septo-optic dysplasia (SOD), also called De Morsier’s syndrome, is a highly heterogeneous condition comprising a spectrum of central nervous system malformations that involves in various degrees the optic nerves, the hypothalamic–pituitary axis, and other midline structures such as the septum pellucidum and the corpus callosum. In a discrete number of cases, schizencephaly, agenesis of the corpus callosum or other cortical malformations are associated (SOD-plus). The authors present a 6-year-old boy with dyskinetic cerebral palsy (athetoid-dystonic subtype) associated with SOD-plus. Cranial magnetic resonance imaging (cMRI) revealed the total absence of septum pellucidum, optic nerve hypoplasia, hypoplasia of the corpus callosum and right occipital cortical dysplasia. The patient was diagnosed with septo-optic dysplasia-plus syndrome based on the cMRI findings. To the best of our knowledge, this is the first reported case in which defects of midline brain structures, like in SOD-plus, are associated with a significant hyperkinetic movement disorder such as dyskinesia.  相似文献   
992.
We evaluated the influence of iNOS-derived NO on the mechanics, inflammatory, and remodeling process in peripheral lung parenchyma of guinea pigs with chronic pulmonary allergic inflammation. Animals treated or not with 1400 W were submitted to seven exposures of ovalbumin in increasing doses. Seventy-two hours after the 7th inhalation, lung strips were suspended in a Krebs organ bath, and tissue resistance and elastance measured at baseline and after ovalbumin challenge. The strips were submitted to histopathological measurements. The ovalbumin-exposed animals showed increased maximal responses of resistance and elastance (p < 0.05), eosinophils counting (p < 0.001), iNOS-positive cells (p < 0.001), collagen and elastic fiber deposition (p < 0.05), actin density (p < 0.05) and 8-iso-PGF2α expression (p < 0.001) in alveolar septa compared to saline-exposed ones. Ovalbumin-exposed animals treated with 1400 W had a significant reduction in lung functional and histopathological findings (p < 0.05). We showed that iNOS-specific inhibition attenuates lung parenchyma constriction, inflammation, and remodeling, suggesting NO-participation in the modulation of the oxidative stress pathway.  相似文献   
993.
A 40-year-old male developed swallowing difficulties, loss of strength, and imbalance. On admission, the patient exhibited bifacial, extremity weakness, ataxia, impaired sensation, and areflexia. Electrophysiology and nerve biopsy suggested demyelination. Spinal fluid revealed increased protein content. Plasmapheresis showed benefit, but neuropathy relapsed. At second recurrence, urine analysis showed heavy proteinuria. Renal biopsy revealed focal segmental glomerulosclerosis (FSGS). Methylprednisolone and oral cyclophosphamide were given. Long-term steroids and immunoglobulin showed steady benefit. Concurrence of chronic inflammatory demyelinating polyneuropathy and FSGS suggests synergistic cellular and humoral autoimmune mechanisms related to either cross-reactivity within antigenic targets or mimicry between neural and renal epitopes.  相似文献   
994.
Quantitative magnetization transfer imaging provides in vivo estimates of liquid and semisolid constituents of tissue, while estimates of the liquid subpopulations, including myelin water, can be obtained from multicomponent T2 analysis. Both methods have been suggested to provide improved myelin specificity compared to conventional MRI. The goal of this study was to investigate the sensitivity of each technique to the progression of acute, gadolinium‐enhancing regions of multiple sclerosis. Magnetization transfer and T2 relaxometry data were acquired longitudinally over the course of 1 year in five relapsing‐remitting multiple sclerosis patients and in five healthy controls. Parametric maps were analyzed in enhancing lesions and normal‐appearing white matter regions. Quantitative magnetization transfer parameters in lesions were most abnormal at the time of enhancement and followed a pattern of recovery over subsequent months. Lesion myelin water fraction was abnormal but did not show a significant trend over time. Quantitative magnetization transfer was able to track the degree and timing of the partial recovery in enhancing multiple sclerosis lesions in a small group of patients, while the recovery was not detected in myelin water estimates, possibly due to their large variability. Our data suggest the recovery is characterized by quick resolution of inflammation and a slower remyelination process. Magn Reson Med, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
995.
Hormesis is a biphasic dose-response relationship, occurring when low concentrations of toxic agents elicit apparent improvements. In this work, the ability of sub-inhibitory concentrations of Tetracycline to induce hormetic response in a model organism was investigated. To this aim a reference strain of Escherichia coli, MG1655, was exposed to six decreasing doses of Tetracycline (between 0.12 and 0.00375 μg/ml), much lower than the Minimal Inhibitory Concentration (4 μg/ml). An hormetic increase was observed at the intermediate concentrations (0.015-0.03 μg/ml) of the tested range. The Colony Forming Unit number, indeed, rose up to 141% and 121% as compared to the control. At the highest (0.12 μg/ml) and lowest (0.00375 μg/ml) concentrations a slight decrease in CFU number was found. Results demonstrated that, in Escherichia coli, low concentrations of Tetracycline bias the bacterial numerical increase through a hormetic response; the dose-response curve describing this numerical increase is an U-inverted curve. Furthermore, these data confirm that hormesis is common to many - if not all - living systems, including bacteria; they underline the relevance of a deepened knowledge of both the effects and the possible consequences of exposure to low doses of contaminants.  相似文献   
996.
Collagenases are critical reagents determining yield and quality of isolated human pancreatic islets and may affect islet transplantation outcome. Some islet transplantation centers have compared 2 or more collagenase blends; however, the results regarding differences in quantity and quality of islets are conflicting. Thus, for the first time, a mixed treatment comparison (MTC) meta-analysis was carried out to compile data about the effect of different collagenases used for human pancreas digestion on islet yield, purity, viability and stimulation index (SI). Pubmed, Embase and Cochrane libraries were searched. Of 755 articles retrieved, a total of 15 articles fulfilled the eligibility criteria and were included in the MTC meta-analysis. Our results revealed that Vitacyte and Liberase MTF were associated with a small increase in islet yield (islet equivalent number/g pancreas) when compared with Sevac enzyme [standardized mean difference (95% credible interval – CrI) = −2.19 (−4.25 to −0.21) and −2.28 (−4.49 to −0.23), respectively]. However, all other enzyme comparisons did not show any significant difference regarding islet yield. Purity and viability percentages were not significantly different among any of the analyzed digestion enzymes. Interestingly, Vitacyte and Serva NB1 were associated with increased SI when compared with Liberase MTF enzyme [unstandardized weighted mean difference (95% CrI) = −1.69 (−2.87 to −0.51) and −1.07 (−1.79 to −0.39), respectively]. In conclusion, our MTC meta-analysis suggests that the digestion enzymes currently being used for islet isolation works with similar efficiency regarding islet yield, purity and viability; however, Vitacyte and Serva NB1 enzymes seem to be associated with an improved SI as compared with Liberase MTF.  相似文献   
997.
998.
ObjectiveThe effects of a cafeteria diet on the small intestine were investigated in adult Wistar rats under sedentary conditions and after physical training.MethodsParameters including morphometry, enzyme activities, and total myenteric populations in the jejunum were evaluated.ResultsThe cafeteria diet, characterized as hyperlipidic, produced obese rats, corroborated by increases in the Lee index and the weights of the periepididymal and retroperitoneal adipose tissues (P < 0.01). Obesity caused increases in the length of the small intestine, villi height, crypt depth, whole-wall thickness (P < 0.05), and the enzymatic activities of alkaline phosphatase, lipase, and sucrase (P < 0.01), in addition to a reduction in the number of goblet cells (P < 0.05). With reference to the jejunal intrinsic innervations, the total number and area of myenteric neurons was unchanged regardless of the group. Physical training promoted 1) a reduction of the weight in the retroperitoneal and periepididymal adipose tissues (P < 0.05) and 2) an increase in the thickness of the muscular layer (P < 0.05).ConclusionThe cafeteria diet promoted obesity in rodents, leading to alterations in morphometry and enzymatic intestinal parameters, which were partily attenuated by physical training.  相似文献   
999.
This paper analyses the implementation level of a breast-feeding incentive program at Government healthcare facilities in Recife, Pernambuco State, Brazil, through a normative assessment conducted through 84 Family Health Teams and at 42 Health Centers in January 2002. A tool containing structured questions was used, related to rules and routines for promoting breast-feeding. The Family Health Teams performed better, with the actions implemented in 7.1% of these Teams and at none of the Health Centers; they were rated as 'not implemented' for 1.2% of the Family Health Teams and 47.6% of the Health Centers. This leads to the conclusion that implementation levels are not satisfactory, reflecting difficulties in breaking away from clinical practice and individual habits in order to introduce universal and all-round health promotion measures.  相似文献   
1000.
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