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991.
For cardiac regenerative therapy intramyocardial catheter guided cell transplantations are targeted to the infarct border zone (IBZ) i.e. the closest region of viable myocardium in the vicinity of the infarct area. For optimal therapeutic effect this area should be accurately identified. However late gadolinium enhanced magnetic resonance imaging (LGE-MRI) is the gold standard technique to determine the infarct size and location, electromechanical mapping (EMM) is used to guide percutaneous intramyocardial injections to the IBZ. Since EMM has a low spatial resolution, we aim to develop a practical and accurate technique to fuse EMM with LGE-MRI to guide intramyocardial injections. LGE-MRI and EMM were obtained in 17 pigs with chronic myocardial infarction created by balloon occlusion of LCX and LAD coronary arteries. LGE-MRI and EMM datasets were registered using our in-house developed 3D CartBox image registration software toolbox to assess: (1) the feasibility of the 3D CartBox toolbox, (2) the EMM values measured in the areas with a distinct infarct transmurality (IT), and (3) the highest sensitivity and specificity of the EMM to assess IT and define the IBZ. Registration of LGE-MRI and EMM resulted in a mean error of 3.01 ± 1.94 mm between the LGE-MRI mesh and EMM points. The highest sensitivity and specificity were found for UV <9.4 mV and bipolar voltage <1.2 mV to respectively identify IT of ≥5 and ≥97.5 %. The 3D CartBox image registration toolbox enables registration of EMM data on pre-acquired MRI during the EMM guided procedure and allows physicians to easily guide injections to the most optimal injection location for cardiac regenerative therapy and harness the full therapeutic effect of the therapy.  相似文献   
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Over the past decade, treatment options for patients with multiple myeloma (MM) have improved substantially, resulting in better response rates and prolonged overall survival (OS). Nevertheless, MM remains a challenging disease, especially if renal insufficiency (RI) or extensive pre-treatment aggravates the assignment of the optimal treatment schedule. In this retrospective study, we analyzed the outcome of lenalidomide plus dexamethasone in 167 patients with relapsed or refractory MM with focus on RI. The baseline creatinine clearance (CLCr) was normal in 94 patients (CLCr ≥ 80 ml/min), while RI was observed in 73 patients, including 40 patients with mild RI (50 ≤ CLCr < 80 ml/min) and 33 patients with moderate or severe RI (CLCr < 50 ml/min). Response rates declined depending on the severity of RI, being 67% among patients with normal kidney function, 60% among patients with mild RI and 49% among patients with moderate or severe RI. Time to progression (TTP) was significantly reduced in patients with severe RI and in case of >2 previous treatment lines. OS was not significantly different between patients with normal and impaired renal function. In contrast, the number of previous treatment lines (2 vs. <2) and the use of novel agents like bortezomib or thalidomide prior to lenalidomide plus dexamethasone therapy had a more adverse effect on OS. In conclusion, lenalidomide plus dexamethasone is an effective regimen for relapsed or refractory patients with MM complicated by RI with manageable toxicity.  相似文献   
995.
Angiogenesis has been associated with the growth, dissemination and metastasis and has been shown to be a prognostic. Although there are some data suggesting that angiogenesis may have a role in the pathophysiology of leukemia, its role in patient prognosis is yet to be defined. We analyzed the expression level of vascular endothelial growth factor (VEGF), an angiogenesis promoter and its possible- prognostic value in bone marrow samples at the time of diagnosis and remission of acute childhood leukemia patients. Besides 46 patients diagnosed as ALL or AML, 16 children were also included as a control group in the study. Our data have demonstrated that VEGF levels of AML patients were found higher than the control group statistically (P = 0.022). However we could not find any significant difference between VEGF levels of diagnosis and remission in both AML and ALL groups by blastic VEGF expression (P > 0.05). In this study the higher levels of VEGF in AML patients is one of the main findings although we were not able to assess any role of VEGF in predicting prognosis in pediatric leukemia patients by evaluating blastic cell VEGF expression. These results have demonstrated that the relationship between angiogenesis or angiogenesis promoters and hematological malignancies is not clear and simple as different methods or different cells beside different angiogenesis promotors are involved to these studies. So that not only tumor cells and their cytokines but also surrounding cells and their cytokines must be taken into consideration with the standardized study methods in the further studies to obtain a promising treatment approach.  相似文献   
996.
We report on a boy with a sudden onset of unilateral skin lesions following tonsillar infection with fever 2 weeks before. The lesions consisted of erythematous macules with scaling affecting trunk, axillar, as well as inguinal region. CRP, blood differential, serum IgG and IgM antibodies (coxsackievirus, cytomegalovirus, parvovirus, herpes virus, varicella zoster virus, human herpesvirus-6/-7), and lesional swabs (bacteria, dermatophytes, yeasts) were uneventful.  相似文献   
997.
PEGylation is a modification commonly used to increase the half-life of therapeutic proteins. The strategy for immunogenicity testing of these compounds should include methods to detect both anti-protein and anti-PEG antibodies. We previously reported a method for the detection of anti-PEG antibodies using ProterixBio’s (formerly BioScale) acoustic membrane microparticle (AMMP) technology. Our initial method development work showed the assay was capable of detecting antibodies in human serum with a sensitivity of 1 μg/mL with good reproducibility (CV?<?7%). Since the publication of this initial paper, additional experimentation was performed in an effort to validate the assay for support of clinical sample analysis. This additional data indicate that the method has high variability (CV%?>?20) and is unsuitable to support clinical sample analysis.  相似文献   
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Obstructive Sleep apnea can be caused by fluid shift from the legs to the neck that narrows the upper airway (UA) and contributes to changes in tracheal sound. Tracheal sound is generated from the turbulent airflow in the pharynx and respiratory airways and it has recently been used to estimate increases in neck fluid volume (NFV). However, tracheal sound is also highly variable among people, especially across the sexes. In this paper, a novel method is proposed to select tracheal sound features towards estimating NFV in men and women separately. To validate this method, it was applied to the tracheal sound data of 28 healthy individuals. Our proposed feature selection algorithm is based on sparse representations and incorporates NFV to maximize the relevance of selected features. This feature selection eliminates the dependence of the previous methods on calibrating the model for every individual. Two models, regression and Kalman filters, are then used to estimate NFV from selected features. Kalman filter obtains the highest performance, estimating NFV with more than 90% accuracy in both men and women. This algorithm can be used to develop non-invasive acoustic technologies to investigate the effects of fluid on UA anatomy in general applications. These results could be used to develop convenient devices to monitor the neck edema and its contribution to sleep apnea severity in fluid retaining patients such as heart or renal failure.  相似文献   
1000.
Chimerism occurs naturaly throughout gestation and can also occur as a consequence of transfusion and transplantation therapy. It consists of the acquisition and long-term persistence of a genetically distinct population of allogenic cells inside another organism. Previous reports have suggested that feto-maternal microchimerism could exert a beneficial effect on the treatment of hematological and solid tumors in patients treated by PBSCT. In this review we report the mechanism of transplacental fetal stem cell trafficking during pregnancy and the effect of their long-term persistence on autoimmunity, GVHD, PBSCT, cancer and stem cell treatment.  相似文献   
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