排序方式: 共有183条查询结果,搜索用时 0 毫秒
1.
Nadezda Alexeyeva Leonard Matisen Agu Saar Päivi Laaksonen Kyösti Kontturi Kaido Tammeveski 《Journal of electroanalytical chemistry (Lausanne, Switzerland)》2010,642(1):6-12
In this paper, the electrochemical reduction of oxygen has been studied on gold nanoparticle/multi-walled carbon nanotube (AuNP/MWCNT) modified glassy carbon (GC) electrodes in 0.5 M H2SO4 using the rotating disk electrode (RDE) method. The AuNP/MWCNT catalysts were prepared by chemical deposition of AuNPs onto MWCNTs spontaneously grafted with 4-nitrophenyl groups. The composite electrode was characterised by transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and cyclic voltammetry (CV). The oxygen reduction behaviour of these electrodes was compared with that of a bulk gold electrode. The AuNP/MWCNT catalyst showed a pronounced electrocatalytic activity towards O2 reduction in acid media. The half-wave potential of O2 reduction on the AuNP/MWCNT catalyst shifted ca 80 mV to more positive potentials as compared to that of a polished Au electrode. The kinetic parameters of oxygen reduction were determined and the specific activity of the hybrid electrode was slightly higher than that of the bulk Au electrode. 相似文献
2.
Lusine Nazaryan Eunice G Stefanou Claus Hansen Nadezda Kosyakova Mads Bak Freddie H Sharkey Theodora Mantziou Anastasios D Papanastasiou Voula Velissariou Thomas Liehr Maria Syrrou Niels Tommerup 《European journal of human genetics : EJHG》2014,22(3):338-343
Next-generation mate-pair sequencing (MPS) has revealed that many constitutional complex chromosomal rearrangements (CCRs) are associated with local shattering of chromosomal regions (chromothripsis). Although MPS promises to identify the molecular basis of the abnormal phenotypes associated with many CCRs, none of the reported mate-pair sequenced complex rearrangements have been simultaneously studied with state-of-the art molecular cytogenetic techniques. Here, we studied chromothripsis-associated CCR involving chromosomes 2, 5 and 7, associated with global developmental and psychomotor delay and severe speech disorder. We identified three truncated genes: CDH12, DGKB and FOXP2, confirming the role of FOXP2 in severe speech disorder, and suggestive roles of CDH12 and/or DGKB for the global developmental and psychomotor delay. Our study confirmes the power of MPS for detecting breakpoints and truncated genes at near nucleotide resolution in chromothripsis. However, only by combining MPS data with conventional G-banding and extensive fluorescence in situ hybridizations could we delineate the precise structure of the derivative chromosomes. 相似文献
3.
4.
Fickelscher I Starke H Schulze E Ernst G Kosyakova N Mkrtchyan H MacDermont K Sebire N Liehr T 《Prenatal diagnosis》2007,27(8):783-785
A prenatally ascertained case with a de novo small supernumerary marker chromosome (sSMC) derived from chromosome 1 is reported. Due to a fetal heart defect the parents decided in favour of an induced abortion. Postmortem, a molecular cytogenetic study on eleven formalin fixed, paraffin-embedded tissues of the fetus was performed, to further characterize the levels of mosaicism of the sSMC(1). sSMC presence varied between 13 and 62% within different tissues of sSMC carriers. This finding is something common in sSMC carriers and could explain why up to the present no clinical correlations for sSMC mosaicism and clinical outcome in the corresponding carriers could be established. 相似文献
5.
6.
Non-T cell activation linker (NTAL): a transmembrane adaptor protein involved in immunoreceptor signaling 下载免费PDF全文
Brdicka T Imrich M Angelisová P Brdicková N Horváth O Spicka J Hilgert I Lusková P Dráber P Novák P Engels N Wienands J Simeoni L Osterreicher J Aguado E Malissen M Schraven B Horejsí V 《The Journal of experimental medicine》2002,196(12):1617-1626
A key molecule necessary for activation of T lymphocytes through their antigen-specific T cell receptor (TCR) is the transmembrane adaptor protein LAT (linker for activation of T cells). Upon TCR engagement, LAT becomes rapidly tyrosine phosphorylated and then serves as a scaffold organizing a multicomponent complex that is indispensable for induction of further downstream steps of the signaling cascade. Here we describe the identification and preliminary characterization of a novel transmembrane adaptor protein that is structurally and evolutionarily related to LAT and is expressed in B lymphocytes, natural killer (NK) cells, monocytes, and mast cells but not in resting T lymphocytes. This novel transmembrane adaptor protein, termed NTAL (non-T cell activation linker) is the product of a previously identified WBSCR5 gene of so far unknown function. NTAL becomes rapidly tyrosine-phosphorylated upon cross-linking of the B cell receptor (BCR) or of high-affinity Fcgamma- and Fc epsilon -receptors of myeloid cells and then associates with the cytoplasmic signaling molecules Grb2, Sos1, Gab1, and c-Cbl. NTAL expressed in the LAT-deficient T cell line J.CaM2.5 becomes tyrosine phosphorylated and rescues activation of Erk1/2 and minimal transient elevation of cytoplasmic calcium level upon TCR/CD3 cross-linking. Thus, NTAL appears to be a structural and possibly also functional homologue of LAT in non-T cells. 相似文献
7.
8.
9.
Marija D Zidverc-Trajković J Sternić N Trbojevik-Stanković J Marić I Milić M Stojimirović B 《Vojnosanitetski pregled. Military-medical and pharmaceutical review》2007,64(5):319-323
BACKGROUND/AIM: Hemodialysis (HD) is a therapeutic procedure used to partially correct homeostatic disorders and prevent complications of uremia to appear in the terminal stage of renal insufficiency. The aim of this study was to evaluate and analyze the incidence and features of haedaches in patients undergoing hemodialysis. METHODS: A total of 143 patients, 50 women and 93 men, undergoing hemodialysis, were questionned about their problems with headache using a questionnary designend according to the diagnostic criteria of the Intemational Headache Classification of Headache Disorders from 2004. The patients were separated into two groups: the patients without headache and the patients with repeated headaches. Afterwards, the patients with headaches were further divided into subgroups: the patients who had the headaches before the beginning of HD and patients who experienced repeated headaches with the beginning of HD headache (HDH). In the group of patients with headaches we analyzed characteristics of headache according to which diagnoses of headaches were made, as well as the effects of HD on headaches. We also analyzed features of HDH. The patients with headache were compared to the patients without haedache regarding sex, age, duration of HD, causes of end-stage renal disease, arterial diastolic and systolic blood pressure and serum concentration of hemoglobin, urea nitrogen, creatinine, sodium and potassium. The results were statistically compared. RESULTS: In the group of 143 patients examined, 27 (18.9%) patients had headaches. There were no statistically significant differences between the group of patients with headaches and those without headache regarding to sex, age, duration of HD, causes of end-stage renal disease, serum concentration of hemoglobin, urea nitrogen, creatinine, sodium and potassium. The patients with headaches showed significantlly higher mean values of systolic blood pressure during HD in comparison to the patients without headaches (p = 0.029). There was no statistically significant difference between the two groups regarding the mean values of diastolic blood pressure. Nineteen (13.3%) patients had had headache before starting HD. HD did not have any effect on the characteristics of headaches in more than a half of these patients. In 8 (5.6%) patients we diagnozed HDH using the diagnostic criteria of the International Headache Classification of Headache Disorders from 2004. HDH showed similar caracteristics in all the patients: it appeared mostly in men, during the 4th hour of HD, lasted less than four hours, it was localized bilaterally in the frontal parts of the head, strong in intensity, throbbing and without the associated symptoms. CONCLUSION: The results of our study clearly showed that HDH was a particular entity of headache, not only because of its connenction with HD, but because it had similar characteristics in all the patients in wich it had appeared. Finding out the pathophysiological mechanisms of their occurrence would significantly improve the quality of life style of patients on hemodialysis. 相似文献
10.
Annkathrin Koch Birte Jeiler Jens Roedig Sjoerd J.L. van Wijk Nadezda Dolgikh Simone Fulda 《Neoplasia (New York, N.Y.)》2021,23(5):539
Burkitt''s lymphoma (BL) is a highly aggressive form of B-cell non-Hodgkin''s lymphoma. The clinical outcome in children with BL has improved over the last years but the prognosis for adults is still poor, highlighting the need for novel treatment strategies. Here, we report that the combinational treatment with the Smac mimetic BV6 and TRAIL triggers necroptosis in BL when caspases are blocked by zVAD.fmk (TBZ treatment). The sensitivity of BL cells to TBZ correlates with MLKL expression. We demonstrate that necroptotic signaling critically depends on MLKL, since siRNA-induced knockdown and CRISPR/Cas9-mediated knockout of MLKL profoundly protect BL cells from TBZ-induced necroptosis. Conversely, MLKL overexpression in cell lines expressing low levels of MLKL leads to necroptosis induction, which can be rescued by pharmacological inhibitors, highlighting the important role of MLKL for necroptosis execution. Importantly, the methylation status analysis of the MLKL promoter reveals a correlation between methylation and MLKL expression. Thus, MLKL is epigenetically regulated in BL and might serve as a prognostic marker for treatment success of necroptosis-based therapies. These findings have crucial implications for the development of new treatment options for BL. 相似文献