Low‐density lipoprotein apheresis (LDL‐A) has been shown to reduce proteinuria in a subgroup of nephrotic syndrome patients refractory to immunosuppressive therapy. Factors influencing the efficacy of LDL‐A in nephrotic syndrome are completely unknown. Using a proteomics approach, we aimed to identify biological markers that predict the response to LDL‐A in patients with steroid‐resistant nephrotic syndrome (SRNS). Identification of plasma proteins bound to the dextran‐sulfate column at the first session of LDL‐A was determined by mass spectrometry. To investigate biological factors associated with the response to LDL‐A, we compared profiles of column‐bound proteins between responders (defined by more than 50% reduction of proteinuria after the treatment) and non‐responders by 2‐dimensional gel electrophoresis (2‐DE) coupled to mass spectrometry in seven patients with SRNS. Evaluation of proteins adsorbed to LDL‐A column in patients with SRNS revealed the identity of 62 proteins, which included apolipoproteins, complement components, and serum amyloid P‐component (SAP). Comparative analysis of the column‐bound proteins between responders and non‐responders by 2‐DE demonstrated that apolipoprotein E (APOE) and SAP levels were increased in non‐responders as compared with responders. These results were confirmed by western blotting. Moreover, serum levels of APOE and SAP were significantly higher in the non‐responder group than in the responder group by ELISA. Our data provide comprehensive analysis of proteins adsorbed by LDL‐A in SRNS, and demonstrate that the serum levels of APOE and SAP may be used to predict the response to LDL‐A in these patients. 相似文献
Mal de Meleda is a rare autosomal recessive genodermatosis caused by mutations in the ARS B (SLURP1) gene, with possible founder effects in the Mediterranean and Adriatic regions. We report an affected individual from Indonesia without known consanguinity in the family, suggesting that SLURP1 gene mutations are ubiquitous. Recognition of the phenotype can be confirmed by genetic testing, thus facilitating genetic counselling. 相似文献
The “default-mode” network is an ensemble of cortical regions, which are typically deactivated during demanding cognitive tasks in functional magnetic resonance imaging (fMRI) studies. Using functional connectivity, this network can be conceptualized and studied as a “stand-alone” function or system. Regardless of the task, independent component analysis (ICA) produces a picture of the “default-mode” function even when the subject is performing a simple sensori-motor task or just resting in the scanner. This has boosted the use of default-mode fMRI for non-invasive research in brain disorders. Here, we studied the effect of cognitive load modulation of fMRI responses on the ICA-based pictures of the default-mode function. In a standard graded working memory study based on the n-back task, we used group-level ICA to explore the variability of the default-mode network related to the engagement in the task, in 10 healthy volunteers.
The analysis of the default-mode components highlighted similarities and differences in the layout under three different cognitive loads. We found a load-related general increase of deactivation in the cortical network. Nonetheless, a variable recruitment of the cingulate regions was evident, with greater extension of the anterior and lesser extension of the posterior clusters when switching from lower to higher working memory loads. A co-activation of the hippocampus was only found under no working memory load.
As a generalization of our results, the variability of the default-mode pattern may link the default-mode system as a whole to cognition and may more directly support use of the ICA model for evaluating cognitive decline in brain disorders. 相似文献
It is becoming common to collect data from multiple functional magnetic resonance imaging (fMRI) paradigms on a single individual. The data from these experiments are typically analyzed separately and sometimes directly subtracted from one another on a voxel-by-voxel basis. These comparative approaches, although useful, do not directly attempt to examine potential commonalities between tasks and between voxels. To remedy this we propose a method to extract maximally spatially independent maps for each task that are "coupled" together by a shared loading parameter. We first compute an activation map for each task and each individual as "features," which are then used to perform joint independent component analysis (jICA) on the group data. We demonstrate our approach on a data set derived from healthy controls and schizophrenia patients, each of which carried out an auditory oddball task and a Sternberg working memory task. Our analysis approach revealed two interesting findings in the data that were missed with traditional analyses. First, consistent with our hypotheses, schizophrenia patients demonstrate "decreased" connectivity in a joint network including portions of regions implicated in two prevalent models of schizophrenia. A second finding is that for the voxels identified by the jICA analysis, the correlation between the two tasks was significantly higher in patients than in controls. This finding suggests that schizophrenia patients activate "more similarly" for both tasks than do controls. A possible synthesis of both findings is that patients are activating less, but also activating with a less-unique set of regions for these very different tasks. Both of the findings described support the claim that examination of joint activation across multiple tasks can enable new questions to be posed about fMRI data. Our approach can also be applied to data using more than two tasks. It thus provides a way to integrate and probe brain networks using a variety of tasks and may increase our understanding of coordinated brain networks and the impact of pathology upon them. 相似文献