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11.
Marcy E. MacDonald Hamish S. Scott William L. Whaley Thomas Pohl John J. Wasmuth Hans Lehrach C. Phillip Morris Anne-Marie Frischauf John J. Hopwood James F. Gusella 《Somatic Cell and Molecular Genetics》1991,17(4):421-425
-l-Iduronidase (IDUA) has been intensively studied due to its causative role in mucopolysaccharidosis type I (Hurler, Scheie and Hurler/Scheie syndromes). The recent cloning of a human IDUA cDNA has resulted in a reevaluation of the chromosomal location of this gene. Previously assigned to chromosome 22, IDUA now has been localized to 4p16.3, the region of chromosome 4 associated with Huntington's disease (HD). The existence of a battery of cloned DNA, physical map information, and genetic polymorphism data for this region has allowed the rapid fine mapping of IDUA within the terminal cytogenetic band of 4p. IDUA was found to be coincident with D4S111, an anonymous locus displaying a highly informative multiallele DNA polymorphism. This map location, 1.1×106 bp from the telomere, makes IDUA the most distal cloned gene assigned to 4p. However, it falls within a segment of 4p16.3 that has been eliminated from the HD candidate region, excluding a role for IDUA in this disorder. 相似文献
12.
13.
Hausfater P Fillet AM Rozenberg F Arthaud M Trystram D Huraux JM Lebon P Riou B 《Journal of medical virology》2004,73(1):137-146
Aseptic meningitis is a frequent diagnosis in emergency departments. Nevertheless, viral investigations are not carried out currently and the viral etiology in adult population has not been studied extensively. We conducted a prospective study including all consecutive patients undergoing lumbar puncture during a 15 months period in an adult emergency department. Bloody and purulent cerebrospinal fluid (CSF) were excluded. The main tests undertaken were: CSF genomic amplification by the polymerase chain reaction (PCR) for neurotropic viruses and serum and CSF interferon-alpha (IFN-alpha) measurements. Among 194 patients included, 45 had and 149 did not have aseptic meningitis. Of 45 patients with aseptic meningitis, 10 had alternative non-virological final diagnosis, and 35/45 were presumed to have neurological disorders of viral origin. Patients (27/35) completed virological analysis: 21/27 (78%) had either positive viral PCR (enterovirus: 8 patients, Varicella zoster virus (VZV): 5, Epstein-Barr virus (EBV): 2, herpes simplex virus (HSV): 1, human herpes virus 6: 1) or only raised serum or CSF IFN-alpha (4 patients). Overall, 59% of patients with a positive viral PCR had either CSF or serum raised IFN-alpha. Twentyone patients without meningitis had either positive viral PCR (enterovirus: 3 patients) or only high serum IFN-alpha level (18 patients). In the setting of aseptic meningitis diagnosed in an adult emergency department, viruses are the most common agents encountered, with enterovirus and VZV as the two main etiological agents. Current CSF viral genome amplification and IFN-alpha measurement are informative and could be useful to confirm the viral origin of various neurological disorders, although the sensitivity and specificity of IFN-alpha measurement for the diagnosis of viral infection need further confirmation. 相似文献
14.
Honecker F Kersemaekers AM Molier M Van Weeren PC Stoop H De Krijger RR Wolffenbuttel KP Oosterhuis W Bokemeyer C Looijenga LH 《The Journal of pathology》2004,204(2):167-174
Intercellular contacts, mediated by E-cadherin, are essential for germ cell migration and maturation. Furthermore, it has been suggested that decrease or loss of E-cadherin correlates with tumour progression and invasive behaviour. beta-catenin is involved in a number of different processes, including cell--cell interaction when bound to cadherins, and determination of cell fate in pluripotent cells when activated via the Wnt signal-transduction pathway. To shed more light on the role of these factors in normal fetal germ cell development and the pathogenesis of germ cell tumours (GCTs), the present study investigated the presence and localization of E-cadherin and beta-catenin by immunohistochemistry. E-cadherin was only weakly expressed in or absent from fetal germ cells of the second and third trimesters, and was not expressed in carcinoma in situ/intratubular germ cell neoplasia unclassified (CIS/ITGCNU) and gonadoblastoma, the precursor of an invasive GCT in dysgenetic gonads. In GCTs, it was generally not expressed in seminoma and dysgerminoma, but was found in the vast majority of non-seminoma cells. beta-catenin was found in the cytoplasm of fetal germ cells at all gestational ages and in spermatogenesis in post-pubertal testes. It was also present in CIS/ITGCNU and gonadoblastoma. Whereas seminomas and dysgerminoma were negative, non-seminoma cells were frequently found to express beta-catenin. Expression of both factors therefore reflects the degree of differentiation of these tumours. No differences for either E-cadherin or beta-catenin were observed between samples of tumours resistant or sensitive to chemotherapy, and E-cadherin expression did not correlate with vascular invasion. E-cadherin and beta-catenin therefore play a role in both normal and malignant germ cell development and differentiation that warrants further investigation, but they seem to be of limited value as predictive or prognostic factors in GCTs. 相似文献
15.
Gerdes T Kirchhoff M Lind AM Larsen GV Schwartz M Lundsteen C 《European journal of human genetics : EJHG》2005,13(2):171-175
In routine prenatal diagnostics we used a commercial multiplex ligation-dependent probe amplification (MLPA) kit for aneuploidy screening for chromosomes 13, 18, 21, X and Y. We present the results of 1593 consecutive prenatal samples analysed and diagnosed prior to knowledge of the G-banding analysis during 8-month routine use of computer-assisted MLPA aneuploidy screening. In total, 27 aneuploidies were detected. There were no false positive results while two false negative results could be explained by a placental mosaicism and a partial monosomy, respectively. In total, 3.2% of the samples were inconclusive. We conclude that automatic computer assisted MLPA is a rapid, simple and reliable method for detection of aneuploidies in prenatal diagnostics. 相似文献
16.
Tobin AM Kirby B 《BioDrugs : clinical immunotherapeutics, biopharmaceuticals and gene therapy》2005,19(1):47-57
Psoriasis is a chronic inflammatory skin disease that can lead to significant physical and psychologic distress for patients. Psoriatic arthritis (PsA), originally thought to be quite a mild disorder, is now recognized as a progressive and destructive arthritis. To date, therapies for both these conditions have been non-specific and unable to maintain long-lasting remission. In addition, many of the current therapies have significant adverse effects, limiting their usefulness. However, elucidation of the pathogenesis of psoriasis and PsA at a molecular level and the development of selective biologic agents have led to an enormous expansion of the armamentarium available to psoriasis patients. Two agents (infliximab and etanercept) selectively block the role of the cytokine tumor necrosis factor (TNF)-alpha and have proved effective in clinical trials in the treatment of both the skin and the joint manifestations of psoriasis. A third anti-TNF alpha agent (adalimumab Humira) is licensed for the treatment of rheumatoid arthritis; however, no studies have been published to date on its use in PsA or psoriasis. It is known that TNF alpha is elevated in both the skin and synovium of psoriatic patients and the effectiveness of its blockade by these two agents in psoriasis and PsA confirms its role in their pathogenesis. Randomized, double-blind, placebo-controlled trials have been performed with both agents in the treatment of psoriasis and PsA; in the case of etanercept these have been to support US FDA approval for use in psoriatic arthropathy. These studies are supported by smaller cohorts in open-label studies and anecdotal reports in the literature. Anti-TNF alpha therapy has proved to have disease-reducing activity in PsA and psoriasis and appears to be well tolerated. These studies have generally featured small numbers of patients and, until a larger cohort of treated patients is available, vigilance must be exercised. A considerable body of post-marketing safety data exists on the use of infliximab in rheumatoid arthritis and Crohn disease and for etanercept in rheumatoid arthritis and PsA. Certain issues, particularly the risk of infection, have emerged as features of the use of these agents. It remains to be seen whether effects seen in other disease entities may be extrapolated to psoriatic patients. More long-term data and experience are needed to define the role of anti-TNF alpha agents in the management of psoriasis and PsA. In particular, more studies are required to elucidate the finer points of co-medication; in some studies both agents have been used with other medications but there have been no formal trials of various possible combinations. 相似文献
17.
Kerttula AM Lyytikäinen O Vuopio-Varkila J Ibrahem S Agthe N Broas M Jägerroos H Virolainen A 《Journal of clinical microbiology》2005,43(12):6161-6163
Our point-prevalence survey followed an outbreak of methicillin-resistant Staphylococcus aureus (MRSA) in a long-term care facility and identified five MRSA strains, of which two possessed an outbreak genotype not encountered previously and three had another profile. All of them possessed SCCmec type V. Six methicillin-sensitive S. aureus strains were genotypically related to the epidemic strains. 相似文献
18.
Montandon G Kinkead R Lomenech AM Bairam A Guénard H 《Respiratory physiology & neurobiology》2005,147(1):117-122
Cerebral blood flow is strictly regulated during hypoxic stress. Because of the preponderant role of the brainstem in cardiorespiratory controls, blood flow response to hypoxia is stronger in this region than in the cortex. However, the brainstem is made up of various regions which differ in their responsiveness to chemical stimuli. The objective of this study was to evaluate the distribution of blood flow during hypoxia using microsphere deposition methods in three brainstem regions containing key structures in cardiorespiratory controls: the nucleus tractus solitarus (NTS), the ventral respiratory groups (VRG) and the pontine respiratory groups (PRG). Microsphere injections were made during normoxia (FIO2=0.21) and after 15 min of hypoxia (FIO2=0.21). Based on this index, blood flow increase during hypoxia was higher in the VRG than in the dorsal part of the brainstem, containing the NTS and the PRG (P=0.002, n=10). These results suggest that blood flow response to hypoxia favours O(2) delivery in brainstem regions involved in respiratory rhythm generation. 相似文献
19.
Daniel Courteix Philippe Obert Anne-Marie Lecoq Patrick Guenon Günter Koch 《European journal of applied physiology》1997,76(3):264-269
The aim of the present study was to analyse the effect of 1 year of intensive swimming training on lung volumes, airway resistance and on the flow-volume relationship in prepubertal girls. Five girls [9.3 (0.5) years old] performing vigorous swimming training for 12?h a week were compared with a control group of 11 girls [9.3 (0.5) years old] who participated in various sport activities for 2 h per week. Static lung volumes, maximal expiratory flows (MEF) at 75, 50 and 25% of vital capacity, 1-s forced expiratory volume (FEV1.0) and airway resistance (R aw) were measured by means of conventional body plethysmograph techniques. Prior to the training period there were no significant differences between the two groups for any of the parameters studied. Moreover, for both groups, all parameters were within the normal range for children of the corresponding age. After 1 year of training, vital capacity (VC), total lung capacity (TLC) and functional residual capacity (FRC) were larger (P<0.05) in the girl swimmers than in the control group, while physical development in terms of height and weight was similar. FEV1.0 (P<0.01), MEF25, MEF50 (P<0.05) and MEF75 as well as the ratio MEF50 / TLC (P<0.05) had increased in the girl swimmers but were unchanged in the control group. R aw tended to be lower in the girl swimmers and higher in the control group. The results indicate that intensive swimming training prepuberty enhances static and dynamic lung volumes and improves the conductive properties of both the large and the small airways. As to the causative mechanism, it can be speculated that at prepuberty intensive swimming training promotes isotropic lung growth by harmonizing the development of the airways and of alveolar lung spaces. 相似文献
20.
Identification of iduronate sulfatase gene alterations in 70 unrelated Hunter patients 总被引:4,自引:0,他引:4
Roseline Froissart Irène Maire Gilles Millat Stéphane Cudry Anne-Marie Birot Véronique Bonnet Olivier Bouton Dominique Bozon 《Clinical genetics》1998,53(5):362-368
We studied 70 unrelated Hunter patients and found a gene alteration in every patient. The molecular heterogeneity was very important. Large gene rearrangements were identified in 14 patients. Forty-three different mutations were identified in the 56 other patients and 31 were not previously described. Deletions and insertions, splice site mutations were associated with a severe phenotype as nonsense mutations except Q531X. Only a few mutations were present in several patients making difficult genotype-phenotype correlations. Mutation identification allows accurate carrier detection improving prenatal diagnosis. The mother was not found to be a carrier in five cases among the 44 sporadic cases. Haplotype analysis demonstrated a higher frequency of mutations in male meiosis. 相似文献