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31.
Wilson disease: novel mutations in the ATP7B gene and clinical correlation in Brazilian patients 总被引:1,自引:0,他引:1
Deguti MM Genschel J Cancado EL Barbosa ER Bochow B Mucenic M Porta G Lochs H Carrilho FJ Schmidt HH 《Human mutation》2004,23(4):398
Wilson disease (WD) is a rare inherited autosomal recessive disorder caused by a defect in a metal transporting P-type ATPase, resulting in copper overload in various tissues and cells. The aim was to assess both the phenotype in Brazilian WD patients and the corresponding ATP7B genotype. Sixty subjects belonging to 46 pedigrees diagnosed as WD were included in this study. Direct sequencing of all 21 exons within ATP7B and their flanking introns was performed. Demographic, clinical, laboratory and histopathological data at the time of diagnosis were obtained. We identified twenty-five mutations, twelve of them reported for the first time. The c.3402delC mutation had the highest allelic frequency (30.8%), followed by the c.2123T>C (p.L708P) (16.7%). Exons 8 and 15 were the site of 62.5% of the mutations. The common European mutation c.3207C>A (p.H1069Q) was not present at all. Phenotype varied greatly among individuals with the same ATP7B genotype. Our data confirm the heterogeneity of ATP7B genotype in Brazilian WD patients. The mutational spectrum is compatible with the Brazilian history of Mediterranean immigration; however, new mutations, and different frequencies and phenotype associated with the previously known mutations characterize this population. Exons 8 and 15 should be preferentially screened in WD cases from Brazil. Phenotype variation among subjects with the same ATP7B genotype suggests that modifying factors play an additional role in the pathogenesis of WD. 相似文献
32.
A Serda Kantarcio?lu Teun Boekhout G Sybren De Hoog Bart Theelen Ayhan Yücel Tuba R Ekmekci Bettina C Fries Reiko Ikeda Adem Koslu Kemal Altas 《Medical mycology》2007,45(2):173-181
Environmental fungi, in particular primary pathogens and Cryptococcus spp. can be responsible for skin lesions mimicking sporotrichosis. In this paper, we report a case of subcutaneous cryptococcosis in an apparently healthy, young male patient due to a non-C. neoformans Cryptococcus species, C. diffluens. The isolate showed in vitro phenotypic switching that may affect virulence and host inflammatory and immune responses, and in vitro resistance to amphotericin B and 5-flucytosin. This species shares several phenotypic traits with C. neoformans, and, therefore, decisive diagnosis should be based on biopsy and culturing results followed by molecular identification. 相似文献
33.
To investigate the mechanism underlying tactile spatial attention, reaction times (RTs) and event-related potentials (ERPs) were recorded in response to mechanical stimuli delivered to the hands. At the start of each trial cues indicated either the correct (valid) or incorrect (invalid) tactile stimulus location or were uninformative (neutral). RT costs (suppression of invalid compared to neutral trials) were found to be larger than benefits (enhancement of valid compared to neutral trials). ERPs showed that costs and benefits contribute equally to attentional modulations of the somatosensory N140 component, whereas these were largely due to costs at longer latencies. These results differ from the pattern of attentional ERP modulations previously found for vision and audition, where costs precede benefits, and therefore suggest that the mechanisms of attentional selectivity in touch might be different from attentional processes in other modalities. 相似文献
34.
Site-independent prognostic value of chromosome 9q loss in primary gastrointestinal stromal tumours 总被引:5,自引:0,他引:5
Gunawan B Schulten HJ von Heydebreck A Schmidt B Enders C Höer J Langer C Schüler P Schindler CG Kuhlgatz J Füzesi L 《The Journal of pathology》2004,202(4):421-429
Although the significance of tumour site for estimating malignant potential in gastrointestinal stromal tumours (GISTs) has recently been recognized, site-specific genetic patterns have not to date been defined. This study examined 52 c-kit-positive primary GISTs (with a mean follow-up of 42.3 months in 51 cases) from three different locations (35 gastric, 12 small intestinal, and five colorectal) using comparative genomic hybridization (CGH). In general, tumour site correlated with key prognostic factors, including tumour size, mitotic rate, proliferative activity, and probable malignant potential. Furthermore, several DNA copy number changes showed a site-dependent pattern. These included losses at 14q (gastric 83%, intestinal 35%; p = 0.001), losses at 22q (gastric 46%, intestinal 82%; p = 0.02), losses at 1p (gastric 23%, intestinal 88%; p = 1 x 10(-5)), losses at 15q (gastric 14%, intestinal 59%; p = 0.002), losses at 9q (gastric 14%, intestinal 53%; p = 0.006), and gains at 5p (gastric 11%, intestinal 53%; p = 0.002). These data demonstrate strong site-dependent genetic heterogeneity in GISTs that may form a basis for subclassification. Prognostic evaluation of DNA copy number changes identified losses at 9q as a site-independent prognostic marker associated with shorter disease-free survival (p = 0.03) and overall survival (p = 0.002). Furthermore, 9q loss also appeared to carry prognostic value in predicting overall survival for patients with advanced or progressive GISTs (p = 0.003). 相似文献
35.
Foulet-Rogé A Josselin N Guyetant S Gardet JJ Besancon A Saint-André JP Fabiani B 《Endocrine pathology》2002,13(3):227-233
We report a case of a 42-yr-old woman with Langerhans cell histiocytosis (LCH) confined to the thyroid and associated with
lymphocytic thyroiditis and a papillary microcarcinoma. This patient remains free of symptoms 14 mo after surgery. Thyroid
LCH is rare. In children, it usually occurs as part of a multisystemic disease, whereas it is usually exclusive in adults.
Isolated thyroid LCH is frequently associated with another thyroid disease, especially lymphocytic thyroiditis, suggesting
that it is a reactive process rather than a neoplastic proliferation. The prognosis of isolated thyroid LCH is good. However,
because it can rarely precede or reveal a multisystemic disease, additional investigations as well as a prolonged follow-up
are justified. 相似文献
36.
Update on Pneumocystis carinii f. sp. hominis Typing Based on Nucleotide Sequence Variations in Internal Transcribed Spacer Regions of rRNA Genes 总被引:6,自引:0,他引:6
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Chao-Hung Lee Jannik Helweg-Larsen Xing Tang Shaoling Jin Baozheng Li Marilyn S. Bartlett Jang-Jih Lu Bettina Lundgren Jens D. Lundgren Mats Olsson Sebastian B. Lucas Patricia Roux Antonietta Cargnel Chiara Atzori Olga Matos James W. Smith 《Journal of clinical microbiology》1998,36(3):734-741
Pneumocystis carinii f. sp. hominis isolates from 207 clinical specimens from nine countries were typed based on nucleotide sequence variations in the internal transcribed spacer regions I and II (ITS1 and ITS2, respectively) of rRNA genes. The number of ITS1 nucleotides has been revised from the previously reported 157 bp to 161 bp. Likewise, the number of ITS2 nucleotides has been changed from 177 to 192 bp. The number of ITS1 sequence types has increased from 2 to 15, and that of ITS2 has increased from 3 to 14. The 15 ITS1 sequence types are designated types A through O, and the 14 ITS2 types are named types a through n. A total of 59 types of P. carinii f. sp. hominis were found in this study. 相似文献
37.
Vrolijk JM Kaul A Hansen BE Lohmann V Haagmans BL Schalm SW Bartenschlager R 《Journal of virological methods》2003,110(2):201-209
Overall treatment results of chronic hepatitis C have improved markedly with the introduction of pegylated interferon-alpha (PEG–IFN-) and ribavirin combination therapy. However, cure rates in the most common genotype 1 infection are still unsatisfactory. IFN- dose–response studies on viral kinetics suggest that inadequate dosing might be a key factor but drug levels have hardly been tested, which is in part due to difficulties in measuring this cytokine in patient samples. We have shown recently that hepatitis C virus (HCV) replicons are highly sensitive to IFN-. In this report we tested whether the replicon system could be used as a sensitive bioassay to determine the amount of biologically active IFN- in serum or heparinized plasma of patients under therapy. To facilitate the measurements, a stably replicating subgenomic HCV RNA was developed that carries the gene encoding the firefly luciferase. Dose response studies with IFN- demonstrate that the amount of expressed luciferase directly correlates with the level of HCV replication. By using this cell-based assay, serum samples of HCV patients treated with different types and doses of IFN- were analyzed in parallel to IFN- standards made by serial dilutions of the same type of IFN- the patient was treated with. Based on nonlinear logistic models serum concentrations corresponding to 1.3–19 U/ml were determined in patients under standard or high dose IFN- therapy, and from 3.8 to 4.1 ng/ml in patients treated with PEG IFN-. In conclusion, the HCV-replicon based bioassay allows determining the levels of biologically active IFN- in serum and heparinized plasma of patients under treatment. 相似文献
38.
Hamzei F Dettmers C Rijntjes M Glauche V Kiebel S Weber B Weiller C 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,146(3):273-281
The aim of this functional magnetic resonance imaging study was to investigate differences in visuomotor control with increasing task complexity. Twelve right-handed volunteers were asked to perform their signature under different degrees of visual control: internally generated movement with closed eyes, signing with open eyes, tracking the line of the projected signature forwards, and tracking the line of the projected signature backwards. There was a gradual onset and disappearance of activation within a distributed network. Parietal, lateral and medial frontal brain areas were activated during all conditions, confirming the involvement of a parieto-frontal system. The weight of activation shifted with increasing task complexity. Internally generated movements activated predominantly the inferior parietal lobule and the ventral premotor cortex, as well as the rostral cingulate area, pre-supplementary motor area (pre-SMA) and SMA proper. Opening the eyes reduced SMA and cingulate activation and activated increasingly the occipito-parietal areas with higher task complexity. Visually guided movements produced an activation predominantly in the superior parietal lobule and dorsal premotor cortex. This study bridges human activation studies with the results of neurophysiological studies with monkeys. It confirms a gradual transition of visuomotor control with increasing task complexity within a distributed parieto-frontal network. 相似文献
39.
C. Seidl V. Brixner T. Müller-Kuller W. Sireis P. Costello Z. Cermakova F. Delaney A. M. Douglas M. Nightingale J. P. Van Galen M. O’Connell W. Siegel L. Sobaga J. De Wit E. Seifried 《ISBT科学丛刊》2008,3(1):54-62
The European blood legislation has defined several key quality elements to achieve Good Manufacturing Practice (GMP) in the field of blood transfusion. During the recent years, the blood legislation is in the process of implementation throughout its member states. Following the Directive 2002/98/EC, Directive 2005/62/EC has given further requirements for quality-management systems to be fulfilled by blood establishments. In addition, GMP/Good Laboratory Practice (GLP) and ISO standards are used inter alia by blood establishments. In order to support the implementation of the blood legislation, the European Public Health Work Plan (2005/2007) has cofunded two projects, led by the German Red Cross and supported by the European Blood Alliance, delivering a common European Standard Operating Procedure (SOP) methodology (EU-Q-Blood-SOP) and criteria and standards for the inspection of blood establishments (EUBIS). The EU-SOP manual will assist blood establishments in preparing for the inspection of their services related to the implementation of quality relevant elements required by the EU Directive 2002/98/EC and its technical annexes. The standards and criteria for inspection of blood establishments will cross-reference existing quality standards to the directive requirements and define requirements for the structure of quality-management systems based on the directive 2002/98/EC and its technical annexes. Based on these requirements, inspection standards and criteria are developed to assist in the independent assessment of quality systems established by individual blood establishments. These assessments are done in relation to the requirements defined by the European Union legislation on blood, in order to safeguard the quality of blood and to achieve continuous improvement of its quality throughout Europe. 相似文献
40.
The distribution of glutamate receptors in transverse hippocampal sections has been well investigated. However, in spite of the known septotemporal gradients of hippocampal connectivity no systematic studies exist about the distribution of glutamate receptors along the septotemporal (longitudinal) hippocampal axis. Therefore, in the present study this issue was investigated using receptor autoradiography for the [3H]MK-801, [3H]AMPA and [3H]Kainate binding sites. Hippocampi from 30-day-old rats were sectioned perpendicularly to their longitudinal axis, yielding a total of 25–30 equidistantly spaced autoradiographs for each hippocampus. For each section layer-specific concentrations of binding sites were calculated by the aid of a computerized image analysing system. The dependency of concentrations of binding sites on the septotemporal position was evaluated by regression analysis. Gradients of binding were confined to distinct hippocampal layers. Significant septotemporal gradients of [3H]MK-801 binding were observed in selected layers of CA1 and the dentate gyrus, a septal to temporal decrease of binding in the oriens and radiatum layers of CA1 being most prominent. For [3H]AMPA, significant septotemporal gradients of binding were restricted to layers of CA3, CA4 and the dentate gyrus, with values generally increasing from septal to temporal levels. The observed septotemporal gradients possibly reflect functional segregations along the longitudinal hippocampal axis and could be important for the comparability of ligand binding studies using transverse hippocampal sections or hippocampal slice cultures. 相似文献