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排序方式: 共有402条查询结果,搜索用时 15 毫秒
1.
Highly resolving two-dimensional gels for protein sequencing.   总被引:6,自引:3,他引:3       下载免费PDF全文
Two-dimensional (2D) PAGE, using carrier ampholytes for the first-dimension separation, has provided a tool for the simultaneous analysis of cellular proteins. To extend the utility of 2D PAGE to the preparative level, we have investigated the use of immobilized pH gradients (IPG) for the first-dimension separation. The results we have obtained indicate that as much as 1 mg of cellular protein can be loaded onto a single IPG gel without loss of resolution. Mutant polypeptides previously detected in carrier ampholyte-based 2D gels were equally detectable in IPG-based 2D gels. With IPG gels several hundred cellular polypeptides can be isolated, from as few as 10 gels, in sufficient amount for sequencing with current sequencing technology. We therefore conclude that IPG greatly enhances the prospects for the large-scale sequencing of cellular proteins for the development of 2D gel-related protein data bases and for the identification of new polypeptide gene products, with the attendant implications for a genome sequencing effort.  相似文献   
2.
Cardiovascular disease (CVD) remains a major problem for people with type 2 diabetes (T2DM), and the leading cause of death worldwide. We aimed to determine cardiovascular benefits of weight loss with or without remission of diabetes, and to assess utility of plasma biomarkers. 29 people with T2DM were studied at baseline and after dietary weight loss. Change in plasma adipokines and lipid related markers was examined in relation to weight loss, diabetes remission, 10-year cardiovascular risk (QRISK), and duration of diabetes. QRISK decreased markedly after weight loss (18.9 ± 2.2 to 11.2 ± 1.6%, p < 0.0001) in both responders and non-responders, but non-responders remained at higher risk (15.0 ± 2.0 vs. 5.8 ± 1.6%, p < 0.0001). At baseline, plasma GDF-15 was higher in longer diabetes duration (1.19 ± 0.14 vs. 0.82 ± 0.09 ng/mL, p = 0.034), as was the QRISK (22.8 ± 2.6 vs. 15.3 ± 3.4%, p = 0.031). Leptin, GDF-15 and FGF-21 decreased whereases adiponectin increased after weight loss in responders and non-responders. However, the level of FGF-21 remained higher in non-responders (0.58 [0.28–0.71] vs. 0.25 [0.15–0.42] ng/mL, p = 0.007). QRISK change correlated with change in plasma VLDL1-TG (r = 0.489, p = 0.007). There was a positive correlation between rise in HDL cholesterol and the decrease in leptin (r = 0.57, p = 0.001), or rise in adiponectin (r = 0.58, p = 0.001) levels. In conclusion, weight loss markedly decreases cardiometabolic risk particularly when remission of diabetes is achieved. Leptin, adiponectin, GDF-15 and FGF-21 changes were related to weight loss not remission of diabetes. Normalization of 10-year cardiovascular risk and heart age is possible after substantial dietary weight loss and remission of T2DM.  相似文献   
3.
Magnetic resonance contrast enhancement depends on the relative timing of image acquisition. Limited human trials have demonstrated efficacy of intra-arterial gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) in delineating vascular anatomy with X-rays. The present study assessed the ability of dynamic MR during intra-arterial Gd-DTPA administration to demonstrate vascular anatomy compared to conventional angiography as the gold standard. As interventional MR techniques using dedicated magnets proliferate, the ability to perform invasive MR angiography with a conventional magnet would be of great utility at established sites. Four subjects referred for different types of angiography underwent dynamic MR studies, including one with iliac artery stenting (Palmaz P204, Johnson and Johnson). All were examined with conventional angiography, and again after dynamic intra-arterial (IA) Gd-DTPA infusion. Coronal MRI images of the body were acquired using a 1.5-T superconducting magnet (three with a GE Signa, one with Philips NT), fast spoiled gradient echo (FSPGR); echo time (TE) = 4.2 msec, repetition time (TR) = 68-150 msec, flip = 75 degrees, 0-600 s after dilute Gd-DTPA IA bolus injection during sequential breath-hold acquisitions of 13-32 s each. All arteries were detected with dynamic MR. The FSPGR MRI with IA Gd-DTPA administration can provide adequate time and spatial resolution to demonstrate arterial anatomy and arterial stent patency.  相似文献   
4.
Contrast-bolus tracking in the carotid bifurcation was accomplished using an MR angiographic technique with a 3D turbo field-echo readout (TR/TE = 6/3, flip angle = 50 degrees) modified by a keyhole scheme. Optimal visibility of the contrast bolus was achieved by digital subtraction from a reference volume. This technique reliably time-resolves the carotid arteries from the jugular veins.  相似文献   
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6.
The nuclear factor-B (NF-B) path-way has been implicated in tumor B-cell survival, growth, and resistance to therapy. Because tumor cells overcome single-agent antitumor activity, we hypothesized that combination of agents that target differentially NF-B pathway will induce significant cytotoxicity. Therapeutic agents that target proteasome and Akt pathways should induce significant activity in B-cell malignancies as both pathways impact NF-B activity. We demonstrated that perifosine and bortezomib both targeted NF-B through its recruitment to the promoter of its target gene IB using chromatin immunoprecipitation assay. This combination led to synergistic cytotoxicity in Waldenstrom macroglobulinemia (WM) cells that was mediated through a combined reduction of the PI3K/Akt and ERK signaling pathways, found to be critical for survival of WM cells. Moreover, a combination of these drugs with the CD20 monoclonal antibody rituximab further increased their cytotoxic activity. Thus, effective WM therapy may require combination regimens targeting the NF-B pathway.   相似文献   
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Proteomic analysis of mantle-cell lymphoma by protein microarray   总被引:8,自引:3,他引:8       下载免费PDF全文
Mantle-cell lymphoma (MCL) is a unique subtype of B-cell non-Hodgkin lymphoma (NHL) that behaves aggressively and remains incurable. In order to understand the pathogenesis of MCL and design new therapies, it is important to accurately analyze molecular changes in pathways dysregulated in MCL. We used antibody microarrays to compare patterns of protein expression between CD19(+) purified B lymphocytes from normal tonsil and 7 cases of histologically confirmed MCL. Protein overexpression was defined as a higher than 1.3-fold or 2-fold increase in at least 67% of tumor samples compared with normal B-cell control. Of the polypeptides, 77 were overexpressed using the higher than 1.3-fold cutoff, and 13 were overexpressed using the 2-fold cutoff. These included cell cycle regulators (regulator of chromosome condensation 1 [RCC1], murine double minute 2 [MDM2]), a kinase (citron Rho-interacting kinase [CRIK]), chaperone proteins (heat shock 90-kDa protein [Hsp90], Hsp10), and phosphatase regulators (A-kinase anchor protein 1 [AKAP149], protein phosphatase 5 [PP5], and inhibitor 2). The elevated expression of some of these polypeptides was confirmed by immunoblotting and immunohistochemistry, whereas elevated expression of others could not be confirmed, illustrating the importance of confirmatory studies. This study describes a novel technique that identifies proteins dysregulated in MCL.  相似文献   
9.
Arteriovenous malformations (AVM) of the uterus can cause life‐threatening hemorrhage. Unexplained, heavy vaginal bleeding in a reproductive age woman should raise suspicion for an AVM. Here a 37‐year‐old woman had increasingly severe vaginal bleeding for 15 days. Serum β‐hCG was elevated. Two‐dimensional transvaginal ultrasound suggested retained products of conception. Before dilation and curettage (D&C), color Doppler and three‐dimensional (3D) power Doppler demonstrated findings indicative of uterine AVM. A bilateral uterine artery embolization was performed without complications. Three months after uterine artery embolization, 3D power Doppler ultrasonography found complete resolution of the AVM. This case illustrates the importance of assessing both gray‐scale and 3D power Doppler, and the ability of postprocedure Doppler to assess resolution. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43:327–334, 2015  相似文献   
10.
Our previous studies indicate that prolonged caffeine consumption exacerbates renal failure in nephropathy associated with the metabolic syndrome. Reduced activity of the antioxidant defense system and beneficial effects of antioxidant therapy have been reported in diabetic rats and humans. The purpose of this study was to examine the early renal effects of caffeine consumption and the effects of concomitant antioxidant therapy in young obese, diabetic ZSF1 rats. Eleven-week-old male ZSF1 rats were randomized to drink tap water, caffeine (0.1%), tempol (1 mmol/L), or a solution containing caffeine and tempol for nine weeks. Caffeine significantly reduced body weight and glycosuria (weeks 2–9), improved glucose tolerance (week 9), had no effect on elevated plasma triglycerides, plasma cholesterol (week 9) and blood pressure (week 9), and significantly increased plasma cholesterol level (weeks 5 and 9). Yet, as early as after two weeks, caffeine greatly augmented proteinuria and increased renal vascular resistance (RVR) and heart rate (HR: week 9). Tempol had no effects on metabolic status and development of proteinuria, did not alter caffeine-induced metabolic changes and early proteinuria, and attenuated caffeine-induced increase in HR and RVR. Immunohistochemical analysis revealed significant glomerular and interstitial inflammation, proliferation, and fibrosis in control animals. Caffeine augmented the influx of glomerular and interstitial macrophages (ED1+ cells) influx, glomerular and tubular proliferative response, and glomerular collagen IV content. Tempol abolished the exacerbation of renal inflammation, proliferation, and fibrosis induced by caffeine. In conclusion, in nephropathy associated with the metabolic syndrome, caffeine—most likely through the interaction with adenosine receptors and interference with anti-inflammatory and/or glomerular hemodynamic effects of adenosine—augments proteinuria and stimulates some of the key proliferative mechanisms involved in glomerular remodeling and sclerosis. Tempol does not prevent early renal injury (i.e., proteinuria) induced by caffeine, yet abolishes late renal inflammatory, proliferative, and fibrotic change induced by chronic caffeine consumption in obese ZSF1 rats.  相似文献   
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