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71.
We describe an 18-month-old boy with Costello syndrome (CS) with proven partial growth hormone (GH) deficiency and hypoglycemic episodes. The hypoglycemia is deemed to be due to cortisol deficiency. This report represents the second published case of cortisol deficiency in the CS. A brief review of the endocrine disturbances in the syndrome is provided. We highlight the need for careful endocrinological evaluation of individuals with CS. 相似文献
72.
Clustering patterns of LOD scores for asthma-related phenotypes revealed by a genome-wide screen in 295 French EGEA families 总被引:3,自引:0,他引:3
Bouzigon E Dizier MH Krähenbühl C Lemainque A Annesi-Maesano I Betard C Bousquet J Charpin D Gormand F Guilloud-Bataille M Just J Le Moual N Maccario J Matran R Neukirch F Oryszczyn MP Paty E Pin I Rosenberg-Bourgin M Vervloet D Kauffmann F Lathrop M Demenais F 《Human molecular genetics》2004,13(24):3103-3113
A genome-wide scan for asthma phenotypes was conducted in the whole sample of 295 EGEA families selected through at least one asthmatic subject. In addition to asthma, seven phenotypes involved in the main asthma physiopathological pathways were considered: SPT (positive skin prick test response to at least one of 11 allergens), SPTQ score being the number of positive skin test responses to 11 allergens, Phadiatop (positive specific IgE response to a mixture of allergens), total IgE levels, eosinophils, bronchial responsiveness (BR) to methacholine challenge and %predicted FEV(1). Four regions showed evidence for linkage (P=0.001): 6q14 for %FEV(1), 12p13 for IgE, 17q22-q24 for SPT and 21q21 for both SPTQ and %FEV(1). Nine other regions indicated smaller linkage signals (0.001
相似文献
73.
Kemp S Valianpour F Denis S Ofman R Sanders RJ Mooyer P Barth PG Wanders RJ 《Molecular genetics and metabolism》2005,84(2):144-151
X-linked adrenoleukodystrophy (X-ALD) is a progressive neurodegenerative disorder characterized by the accumulation of saturated and mono-unsaturated very long-chain fatty acids (VLCFA) and reduced peroxisomal VLCFA beta-oxidation activity. In this study, we investigated the role of VLCFA biosynthesis in X-ALD fibroblasts. Our data demonstrate that elongation of both saturated and mono-unsaturated VLCFAs is enhanced in fibroblasts from patients with peroxisomal beta-oxidation defects including X-ALD, and peroxisome biogenesis disorders. These data indicate that enhanced VLCFA elongation is a general phenomenon associated with an impairment in peroxisomal beta-oxidation, and not specific for X-ALD alone. Analysis of plasma samples from patients with X-ALD and different peroxisomal beta-oxidation deficiencies revealed increased concentrations of VLCFAs up to 32 carbons. We infer that enhanced elongation does not result from impaired peroxisomal beta-oxidation alone, but is due to the additional effect of unchecked chain elongation. We demonstrate that elongated VLCFAs are incorporated into complex lipids. The role of chain elongation was also studied retrospectively in samples from patients with X-ALD previously treated with "Lorenzo's oil." We found that the decrease in plasma C26:0 previously found is offset by the increase of mono-unsaturated VLCFAs, not measured previously during the trial. We conclude that evaluation of treatment protocols for disorders of peroxisomal beta-oxidation making use of plasma samples should include the measurement of saturated and unsaturated VLCFAs of chain lengths above 26 carbon atoms. We also conclude that chain elongation offers an interesting target to be studied as a possible mode of treatment for X-ALD and other peroxisomal beta-oxidation disorders. 相似文献
74.
Bruce R. Thorley Julie Milland Dale Christiansen Marc B. Lanteri Beth McInnes Ingrid Moeller Pierre Rivailler Branka Horvat Chantal Rabourdin-Combe Denis Gerlier Ian F. C. McKenzie Bruc. E. E. Loveland 《European journal of immunology》1997,27(3):726-734
CD46 (membrane cofactor protein) is a human cell-surface regulator of activated complement and a receptor for the measles virus. A CD46 transgenic mouse line with an expression pattern similar to that of human tissues has been produced, to develop an animal model of (i) the control of complement activation by complement regulators in hyperacute rejection of xenografts, and (ii) measles virus infection. The mouse line was made using a CD46 minigene that includes promoter sequence and the first two introns of genomic CD46, which was coinjected into mouse ova with chicken lysozyme matrix attachment region DNA. A high level of CD46 expression in homozygotic transgenic mice was obtained with spleen cells having approximately 75% of the level found on human peripheral blood mononuclear cells. CD46 was detected in all tissues examined by immunohistochemistry, radioimmunoassay and Western blotting, showing that these mice were suitable for transplantation and measles virus infection studies. It also indicated that the transgene included the important regulatory elements of the CD46 promoter. Transgenic spleen cells were significantly protected in vitro from human complement activated by either the classical or alternative pathways and from alternative pathway rat complement. Furthermore, transgenic mouse hearts transplanted to rats regulated complement deposition in an in vivo model of antibody-dependent hyperacute xenograft rejection. Similar to human lymphocytes, transgenic lymphoblasts could be infected in vitro with measles virus; infected cells expressed viral proteins and produced infectious viral particles. The data demonstrate the suitability of this minigene for obtaining high-level CD46 expression sufficient for enhanced resistance of transgenic cells to complement attack and for obtaining wide tissue distribution of CD46, analogous to human tissues and, therefore, useful for comparative studies. 相似文献
75.
The genome of equine arteritis virus (EAV) produces a 3 coterminal-nested set of six subgenomic (sg) viral RNAs during virus replication cycle, and each set possesses a common leader sequence of 206 nucleotides (nt) in length derived from the 5 end of the viral genome. Given the presence of the leader region within both genomic and sg mRNAs, it is likely to contain cis-acting signals that may interact with cellular or viral proteins for RNA synthesis. Gel mobility shift assays indicated that proteins in Vero cell cytoplasmic extracts formed complexes with the positive (+) and negative (-) strands of the EAV leader RNA. Several cell proteins with molecular masses ranging from 74 to 31 kDa and 58 to 32 kDa were detected in UV-induced cross-linking assays with the EAV leader RNA (+) and (-) strands, respectively. In both cases, intense bands were observed at the 58–52 kDa molecular weight markers. Results from competition gel mobility shift assays using overlapping cold RNA probes spanning the leader RNA (+) strand indicated that nt 140–206 are not necessary for binding to cell proteins. 相似文献
76.
Prevalence of fragilysin gene in Bacteroides fragilis isolates from blood and other extraintestinal samples 总被引:1,自引:0,他引:1 下载免费PDF全文
Foulon I Piérard D Muyldermans G Vandoorslaer K Soetens O Rosseel P Lauwers S 《Journal of clinical microbiology》2003,41(9):4428-4430
Of 166 Bacteroides fragilis isolates, 26.2% of 103 isolates from blood and 20.6% of 63 extraintestinal isolates harbored the fragilysin gene (difference not statistically significant). Clinical characteristics and evolution were comparable in patients with B. fragilis bacteremia with or without this enterotoxin. Fragilysin seems not to be an important virulence factor in B. fragilis disease. 相似文献
77.
In chronic beryllium disease (CBD), a granulomatous lung disease characterized by hypersensitivity to beryllium salts (BE), BE challenge of bronchoalveolar lavage cells induces IFNgamma. Although nitric oxide (NO) is elevated in CBD airways, the effects of NO on CBD IFNgamma responses are unknown. Here we report that BE-stimulated IFNgamma production in CBD lavage cells was markedly reduced (74%) by the NO generator DETA NONOate. Investigation of IFNgamma-stimulatory cytokine involvement indicated that lavage cell IL-18 was significantly increased (fourfold) by BE and reduced (64%) by DETA NONOate but IL-12 was undetectable. IL-18 production was caspase-1-dependent but caspase 1 inhibition reduced IFNgamma only partially (43%). Specific antibody depletion of lavage cell IL-18 yielded marginal reduction (19%) of IFNgamma. Data are the first to show that: (1) BE stimulates IL-18 as well as IFNgamma in CBD; (2) BE cytokine responses are NO-sensitive; and (3) NO down-regulation of IFNgamma involves other sites in addition to IL-18. 相似文献
78.
Martin Bilodeau A. Bertrand Arsenault Denis Gravel Daniel Bourbonnais 《European journal of applied physiology》1991,63(1):24-28
Summary The goal of the present study was to compare electromyogram (EMG) power spectra obtained from step (constant force level) and ramp (progressive increase in the force level) isometric contractions. Data windows of different durations were also analysed for the step contractions, in order to evaluate the stability of EMG power spectrum statistics. Fourteen normal subjects performed (1) five ramp elbow extensions ranging from 0 to 100% of the maximum voluntary contraction (MVC) and (2) three stepwise elbow extensions maintained at five different levels of MVC. Spectral analysis of surface EMG signals obtained from triceps brachii and anconeus was performed. The mean power frequency (MPF) and the median frequency (MF) of each power spectrum were obtained from 256-ms windows taken at 10, 20, 40, 60 and 80% MVC for each type of contraction and in addition on 512-, 1024-and 2048-ms windows for the step contractions. No significant differences (P>0.05) were found in the values of both spectral statistics between the different window lengths. Even though no significant differences (P>0.05) were found between the ramp and the step contractions, significant interactions (P<0.05) between these two types of contraction and the force level were found for both the MPF and the MF data. These interactions point out the existence of different behaviours for both the MPF and the MF across force levels between the two types of contraction. 相似文献
79.
Dominique Bonneau Isabelle Winter-Fuseau Marie-No?lle Loiseau Patrizia Amati Michel Berthier Denis Oriot Carole Beaumont 《Journal of medical genetics》1995,32(10):778-779
This paper reports the cosegregation in a three generation pedigree of dominantly inherited cataract with an abnormally high level of serum ferritin. In this family, circulating L ferritin was raised in all subjects affected by cataract independently of iron overload. We suggest that a disorder of ferritin metabolism could be a new genetic disorder leading to lens opacity. Cataract-hyperferritaemia syndrome could also be a new contiguous gene syndrome involving the L ferritin gene and the gene coding for the lens membrane protein (MP19), which both map to the same region of chromosome 19q. 相似文献
80.
A 1463 gene cattle-human comparative map with anchor points defined by human genome sequence coordinates 总被引:5,自引:0,他引:5 下载免费PDF全文
Everts-van der Wind A Kata SR Band MR Rebeiz M Larkin DM Everts RE Green CA Liu L Natarajan S Goldammer T Lee JH McKay S Womack JE Lewin HA 《Genome research》2004,14(7):1424-1437
A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes. 相似文献