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991.
RM Quinlivan M RCP SA Robb MD C. Sewry PhD V. Dubowitz MD F. Piccolo MD JC Kaplan MD 《Developmental medicine and child neurology》1997,39(11):770-774
An 11-year-old white female presented with progressive proximal muscle weakness and marked calf hypertrophy. Muscle biopsy showed severe dystrophy with normal expression of dystrophin. There was complete absence of the 50kDa dystrophin-associated glycoprotein (alpha-sarcoglycan). DNA analysis showed novel point mutations (one missense and one splicing) in the alpha-sarcoglycan gene at chromosomal location 17q21, confirming the diagnosis of limb-girdle muscular dystrophy type 2D (LGMD-2D). We believe this is one of the first confirmed white cases of primary alpha-sarcoglycanopathy identified in the UK. This case supports the assumption of a wide geographic prevalence of severe childhood onset autosomal recessive muscular dystrophy and genetic heterogeneity. In the future, with improved diagnostic accuracy it is likely that more cases demonstrating primary or secondary deficiency of alpha-sarcoglycan will be identified. We would recommend staining for dystrophin-associated glycoproteins (sarcoglycans) in all new cases of muscular dystrophy with normal dystrophin, and confirmation with DNA analysis where possible. 相似文献
992.
993.
Subcellular localization of the Huntington's disease gene product in cell lines by immunofluorescence and biochemical subcellular fractionation 总被引:7,自引:7,他引:0
De Rooij KE; Dorsman JC; Smoor MA; Den Dunnen JT; Van Ommen GJ 《Human molecular genetics》1996,5(8):1093-1099
Huntington's disease is a progressive neurodegenerative disorder, which is
caused by expansion of a polymorphic (CAG)n repeat in the coding region of
the Huntington's disease gene. The function of huntingtin has not been
elucidated so far. Accordingly, detailed subcellular localization studies
remain useful. In an immunohistochemical study, we have reported huntingtin
to be present in the cytoplasm of cells in the majority of the tissues
studied. In addition, we detected a signal in the nucleus of cells in some
tissues, including neuronal cells. We have further extended these studies
in various mammalian cell lines, using a panel of (affinity-purified)
polyclonal huntingtin antibodies in immunofluorescence, confocal laser
scanning microscopy and biochemical subcellular fractionation studies. In
mouse embryonic fibroblasts, human skin fibroblasts and in mouse
neuroblastoma cells huntingtin was present in the cytoplasm. All five
antibodies, directed against different parts of huntingtin, also showed a
signal in the nucleus. This signal could be competed by the original
antigen. The localization of huntingtin in both cytoplasm and nucleus, was
confirmed by biochemical subcellular fractionation studies. However, in
most other studies, a nuclear location for huntingtin has not been found.
Our results suggest, however, that besides its function(s) in the
cytoplasm, a nuclear function of huntingtin at some stages of
differentiation or in some phases of the cell cycle may not be excluded.
相似文献
994.
Integrin function in chronic lymphocytic leukemia 总被引:2,自引:2,他引:0
Integrins are central to many aspects of the tissue localization of normal and malignant lymphocytes. We examined how integrin function, rather than simple expression, might determine disease behavior in chronic lymphocyte leukemia (CLL). Using fluorescence-activated cell sorting (FACS) and immunoprecipitation, we first established the precise integrin heterodimer expression of a representative group of CLL patients (beta1 consistently present, with variable alpha 3, alpha 4, and alpha 5; alpha 4 beta 7 often expressed; alpha L beta 2 high; alpha V beta 3 absent). Regarding function, we initially examined the ability of CLL cells to interact with endothelium, because such interaction is the initial event determining the entry of CLL lymphocytes into tissues. The abnormal lymphocytes were shown to bind at low levels to unstimulated endothelium via beta 2/intercellular adhesion molecule (ICAM). However, when the endothelium was stimulated, markedly enhanced interaction with endothelium was observed in approximately half the cases; in these patients, the neoplastic population expressed alpha 4 beta 1, which conferred the ability to adhere strongly to stimulated endothelium via the alpha 4 beta 1 ligand, vascular cellular adhesion molecule-1 (VCAM-1). In relation to the migration of CLL cells within tissues, the abnormal lymphocytes showed differential binding to various adhesive proteins; they did not attach to basement membrane components, but displayed variable adhesion to fibronectin (FN). Finally, we examined the role of cell activation in these processes, and showed that activated CLL lymphocyte populations showed an increased capacity to adhere to both endothelium and matrix. Moreover, ex vivo CLL cells showed no capacity to migrate through endothelium/stroma, but were able to do so after cytokine stimulation. These studies show how the constitutive integrin expression/function, the intrinsic activation state of the cell, and the capacity of cytokines to modify integrin-mediated function all combine to determine the different patterns of clinical disease observed in CLL. 相似文献
995.
van Deutekom JC; Bakker E; Lemmers RJ; van der Wielen MJ; Bik E; Hofker MH; Padberg GW; Frants RR 《Human molecular genetics》1996,5(12):1997-2003
Facioscapulohumeral muscular dystrophy (FSHD) is an autosomal dominant
myopathy, clinically characterized by asymmetric weakness of muscles in the
face, shoulder girdle and upper arm. Deletion of an integral number of 3.3
kb repeated units within a highly polymorphic EcoRI fragment at chromosome
4q35, generating a relatively short EcoRI fragment (< 35 kb), has been
shown to cause FSHD1. Probe p13E-11 detects these short fragments in FSHD1
patients, and has therefore been used for diagnostic DNA analysis. However,
the reliability of this analysis has been hampered by cross-hybridization
of p13E-11 to chromosome 10q26-linked EcoRI fragments of comparable size,
which also contain a variable number of 3.3 kb repeated units. Recently, a
BinI restriction site was identified within each of the repeated units
derived from chromosome 10q26, which enables differentiation of the two
polymorphic p13E-11 loci in most cases without haplotype analysis.
Remarkably, applying the differential analysis to screen DNA of 160 Dutch
cases referred to us for FSHD1 diagnosis, we obtained evidence for
subtelomeric exchange of 3.3 kb repeated units between chromosomes 4q35 and
10q26 in affected and unaffected individuals. Subsequently, analysis of 50
unrelated control samples indicated such exchange between chromosomes 4q35
and 10q26 in at least 20% of the population. These subtelomeric
rearrangements have generated a novel interchromosomal polymorphism, which
has implications for the specificity and sensitivity of the differential
restriction analysis for diagnostic purposes. Moreover, the high frequency
of the interchromosomal exchanges of 3.3 kb repeated units suggests that
they probably do not contain (part of) the FSHD1 gene, and supports
position effect variegation as the most likely mechanism for FSHD1.
相似文献
996.
The potential for improved pulmonary nodule detection with scanning equalization radiography (SER) was evaluated by means of observer performance testing during the interpretation of posteroanterior conventional radiographs and SER images of an anthropomorphic chest phantom with simulated nodules. A test set of 200 conventional and 200 SER radiographs of phantoms containing either one nodule or none was interpreted by four radiologists attempting to detect a nodule and indicate a confidence value. Their ability to detect nodules positioned over the lung was slightly improved with SER compared with conventional radiography (sensitivity, .56 vs .70); for nodules over the mediastinum or diaphragmatic areas, it was much improved (sensitivity, .29 vs .64). The results were also analyzed with receiver-operating characteristic methods, which revealed a significant improvement in lesion detect-ability over the thicker body parts with SER images. The capability of equalized chest radiographs to provide improved lesion detectability suggests that SER may set a new standard for film-based chest radiography and have a large clinical application. 相似文献
997.
C. Campana A. Gavazzi R. Marioni A. D'Armini N. Pederzolli C. Larizza C. Berzuini L. Martinelli M. Vigano C. Montemartini 《Transplant international》1992,5(Z1):S221-S223
The prevalence of right ventricular failure after orthotopic heart transplantation, evaluated in 196 patients, was 11.7%, as assessed by the presence during the first postoperative month of right atrial pressure > 10 mm Hg. Two deaths, related to refractory right ventricular failure, were observed within the first month, both in subjects with preoperative pulmonary arteriolar resistances > 5 Wood Units. The haemodynamic profile after heart transplantation showed a significant decrease (P < 0.01) and an early normalization of pulmonary arterial pressure, pulmonary wedge pressure and pulmonary arteriolar resistances, while right atrial pressure slowly decreased until the third month. In a long-term analysis of survival (death within 1 year) the probability of death was significantly related to the values of right atrial pressure and cardiac index during the first month after heart transplantation. Otherwise, the presence of elevated values of right atrial pressure did not show a significant correlation with the echocardiographic right ventricular end-diastolic diameter nor with the presence of right bundle branch block. The careful selection of patients referred for the cardiac transplantation (mean value of pulmonary arteriolar resistances in the evaluated subjects was 2.5 ± 1.5 Wood Units) improves the probability of avoiding the appearance of severe right ventricular failure in the post-operative period in most cases. The best predictor of right ventricular failure remains to be clearly identified. 相似文献
998.
Fetal hyaloid artery: timing of regression with US 总被引:2,自引:0,他引:2
Large-aperture, dynamically focused ultrasonic imaging permits noninvasive, anatomic study of the eye at the millimeter level in the second and third trimesters of pregnancy. The authors report their observations of the hyaloid artery in 210 of 219 fetuses examined with this technique. This vessel is seen in fetuses of 20 weeks gestational age or less and regresses spontaneously at the start of the third trimester. The 210 subjects included 100 who were examined at gestational ages of 16-32 weeks or more and 85 healthy fetuses and 25 with pathologic findings at birth who were examined at 34 weeks gestational age to term. The presence of the hyaloid artery in the mid third trimester was uncommon in healthy subjects (less than 1%) and was not seen in any beyond 29.9 weeks gestational age. However, in nine of the 25 fetuses with abnormalities (five with trisomy syndromes), the vessel was seen at 30.8-36.8 weeks gestational age. The temporarily delayed regression of the hyaloid artery may occur with trisomy 21 syndrome and other forms of retarded brain development. 相似文献
999.
1000.
C A Gidycz S J Lynn C L Rich N L Marioni C Loh L M Blackwell J Stafford R Fite J Pashdag 《Journal of consulting and clinical psychology》2001,69(6):1073-1078
This article summarizes the results of the Ohio University Sexual Assault Risk Reduction Project, which is a program designed to reduce college women's risk for sexual assault. The program was evaluated at 2 separate universities with 762 women. Participants were randomly assigned either to the program or to the no-treatment comparison group, and they completed measures that assessed sexual victimization, dating behaviors, sexual communication, and rape empathy at the pretest and at the 2-month and 6-month follow-ups. At the 2-month follow-up, there were no differences between the groups on any of the outcome measures. However, those women who were moderately victimized during the 2-month follow-up were significantly less likely to be revictimized during the 6-month follow-up period if they participated in the program. 相似文献