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排序方式: 共有678条查询结果,搜索用时 15 毫秒
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AIM: To compare magnetic resonance imaging (MRI) with clinical examination for the detection of muscle abnormality in patients with muscular dystrophy. METHODS: Muscle power in 20 patients with a variety of forms of muscular dystrophy was examined clinically using the Medical Research Council (MRC) grading scale, and patients were subsequently imaged with MRI. MRI and clinical examination for the detection of muscle normality and abnormality were compared using a McNemar chi-squared test to examine differences between the two methods. RESULTS: MRI demonstrated radiological evidence of muscle abnormality more often than clinical examination; 50% of movements assessed as normal on clinical examination were associated with muscle abnormalities on MRI, including a significant proportion where there was severe radiological abnormality, indicating that focally advanced disease may be undetectable clinically. CONCLUSION: The combination of clinical examination and MRI could improve the accuracy of phenotypic characterization of patients with muscular dystrophy, and this in turn could allow a more focussed molecular analysis through muscle biopsy or genetic investigation. This may also be very helpful in the assessment of the degree of muscle compromise not only in the early phases of the disease but especially during follow-up and can be used in therapeutic trials. 相似文献
674.
CR de Andrade PF Leite AC Montezano DA Casolari A Yogi RC Tostes R Haddad MN Eberlin FRM Laurindo HP de Souza FMA Corr��a AM de Oliveira 《British journal of pharmacology》2009,157(4):568-580
Background and purpose:
There are interactions between endothelin-1 (ET-1) and endothelial vascular injury in hyperhomocysteinemia (HHcy), but the underlying mechanisms are poorly understood. Here we evaluated the effects of HHcy on the endothelin system in rat carotid arteries.Experimental approach:
Vascular reactivity to ET-1 and ETA and ETB receptor antagonists was assessed in rings of carotid arteries from normal rats and those with HHcy. ETA and ETB receptor expression was assessed by mRNA (RT-PCR), immunohistochemistry and binding of [125I]-ET-1.Key results:
HHcy enhanced ET-1-induced contractions of carotid rings with intact endothelium. Selective antagonism of ETA or ETB receptors produced concentration-dependent rightward displacements of ET-1 concentration response curves. Antagonism of ETA but not of ETB receptors abolished enhancement in HHcy tissues. ETA and ETB receptor gene expressions were not up-regulated. ETA receptor expression in the arterial media was higher in HHcy arteries. Contractions to big ET-1 served as indicators of endothelin-converting enzyme activity, which was decreased by HHcy, without reduction of ET-1 levels. ET-1-induced Rho-kinase activity, calcium release and influx were increased by HHcy. Pre-treatment with indomethacin reversed enhanced responses to ET-1 in HHcy tissues, which were reduced also by a thromboxane A2 receptor antagonist. Induced relaxation was reduced by BQ788, absent in endothelium-denuded arteries and was decreased in HHcy due to reduced bioavailability of NO.Conclusions and implications:
Increased ETA receptor density plays a fundamental role in endothelial injury induced by HHcy. ET-1 activation of ETA receptors in HHcy changed the balance between endothelium-derived relaxing and contracting factors, favouring enhanced contractility.British Journal of Pharmacology (2009) 157, 568–580; doi:10.1111/j.1476-5381.2009.00165.x; published online 9 April 2009This article is part of a themed section on Endothelium in Pharmacology. For a list of all articles in this section see the end of this paper, or visit: http://www3.interscience.wiley.com/journal/121548564/issueyear?year=2009 相似文献675.
Treves S Vukcevic M Jeannet PY Levano S Girard T Urwyler A Fischer D Voit T Jungbluth H Lillis S Muntoni F Quinlivan R Sarkozy A Bushby K Zorzato F 《Human molecular genetics》2011,20(3):589-600
Prolonged depolarization of skeletal muscle cells induces entry of extracellular calcium into muscle cells, an event referred to as excitation-coupled calcium entry. Skeletal muscle excitation-coupled calcium entry relies on the interaction between the 1,4-dihydropyridine receptor on the sarcolemma and the ryanodine receptor on the sarcoplasmic reticulum membrane. In this study, we directly measured excitation-coupled calcium entry by total internal reflection fluorescence microscopy in human skeletal muscle myotubes harbouring mutations in the RYR1 gene linked to malignant hyperthermia (MH) and central core disease (CCD). We found that excitation-coupled calcium entry is strongly enhanced in cells from patients with CCD compared with individuals with MH and controls. Furthermore, excitation-coupled calcium entry induces generation of reactive nitrogen species and enhances nuclear localization of NFATc1, which in turn may be responsible for the increased IL-6 released by myotubes from patients with CCD. 相似文献
676.
Wood AJ Müller JS Jepson CD Laval SH Lochmüller H Bushby K Barresi R Straub V 《Human molecular genetics》2011,20(24):4879-4890
Fukutin and fukutin-related protein (FKRP) are involved in the glycosylation of α-dystroglycan, a key receptor for basement membrane proteins. Aberrant α-dystroglycan glycosylation leads to a broad spectrum of disorders, ranging from limb girdle muscular dystrophy to Walker-Warburg syndrome. This is the first study investigating a role of fukutin and FKRP-mediated glycosylation in angiogenesis. Transgenic zebrafish expressing enhanced green fluorescent protein in blood vessels were treated with morpholino antisense oligonucleotides that blocked the expression of fukutin, FKRP and dystroglycan. All morphant fish showed muscle damage and vascular abnormalities at day 1 post-fertilization. Intersegmental vessels of somites failed to reach the dorsal longitudinal anastomosis and in more severe phenotypes retracted further or were in some cases even completely missing. In contrast, the eye vasculature was distorted in both fukutin and FKRP morphants, but not in dystroglycan morphants or control fish. The eye size was also smaller in the fukutin and FKRP morphants when compared with dystroglycan knockdown fish and controls. In general, the fukutin morphant fish had the most severe skeletal muscle and eye phenotype. Our findings suggest that fukutin and FKRP have functions that affect ocular development in zebrafish independently of dystroglycan. Despite anecdotal reports about vascular abnormalities in patients affected by dystroglycanopathies, the clinical relevance of such lesions remains unclear and should be subject to further review and investigations. 相似文献
677.
The increasing knowledge about limb girdle muscular dystrophy (LGMD) has clarified many aspects of this extensive group of neuromuscular conditions and has moreover proven their wide clinical and genetic heterogeneity. For these reasons, achieving a precise diagnosis of a particular type of LGMD may be still difficult and requires a comprehensive approach, which includes epidemiology, medical history, clinical examination, laboratory and genetic tests. All of the LGMDs are individually rare and their population frequency is highly variable. The prevalence of the different forms of LGMD in different populations has to be considered for the differential diagnosis. Some characteristic clinical features may help to distinguish subtypes of LGMD however protein analysis on muscle biopsy and genetic testing still represent the gold standard in the diagnosis of these muscular dystrophies. Reaching a precise diagnosis in all patients is important to allow genetic counseling to be properly applied and to direct appropriate medical management with a potential positive impact on the length and quality of life. Moreover, new specific therapeutic approaches, including limited local gene therapy, have been emerging over the last few years and require a precise genetic definition of the conditions. This article will concentrate on the diagnostic process by which these disorders can be defined and the implications of making these diagnoses. 相似文献
678.
A Marceline Tutu van Furth Martijn van der Kuip Anne L van Els Lydia CR Fievez Gini GC van Rijckevorsel Anton van den Ouden Marcel Jonges Matthijs RA Welkers 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(29)
Since May 2022, an international monkeypox (MPX) outbreak has been ongoing in more than 50 countries. While most cases are men who have sex with men, transmission is not restricted to this population. In this report, we describe the case of a male child younger than 10 years with MPX in the Netherlands. Despite thorough source tracing, a likely source of infection has not been identified. No secondary cases were identified in close contacts. 相似文献