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101.
BackgroundHeat shock protein 70 (HSP70) is a significant cellular stress response protein that has intrinsic and extrinsic pathways to protect cells against apoptosis. It is one of the most induced proteins in cancer cells. The aim of the present study is to investigate the significant role of the HSP70 expression in Egyptian patients with breast cancer (BC) and its potential to be as a diagnostic and prognostic marker.Materials and MethodsHSP70 was examined in 155 cases in this prospective study; patients were subdivided into 3 groups: 60 patients with malignant metastatic disease, 60 patients with malignant non-metastatic disease, and 35 patients with benign lesions as control. HSP70 expression was detected using enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC).ResultsMost cases of breast cancer expressed HSP70 in both serum (98.3%) and tumor tissue (90%). A strong positive correlation was found between HSP70 IHC and ELISA (r = 0.811). The mean HSP70 levels, as detected in both patients’ serum by ELISA and tumor tissue by IHC, was significantly higher in patients with BC than in benign cases (P = .001). HSP70 was significantly higher in patients with metastatic BC than in those with non-metastatic BC (P = .001). HSP70 showed positive correlation with tumor size (pT stage) and number of lymph node metastases (P ≤ .001).ConclusionHSP70 is over-expressed in patients with metastatic and non-metastatic BC than in benign cases. A high level of HSP70 either in patient’s serum or in tumor tissue correlated significantly with advanced disease in patients with BC. This present study suggests that HSP70 can serve as a BC biomarker for early screening, diagnosis, and follow-up.  相似文献   
102.
Journal of Neuro-Oncology - Glioblastoma (GBM) is the most fatal brain tumor in adults. Current survival rates of GBM remain below 2 years due to GBM’s aggressive cellular migration...  相似文献   
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Sixty percent of newly diagnosed cancers occur in older adults and more complex planning is required to sustain quality care for older populations. Individualized care incorporating geriatric assessment can predict early mortality and treatment toxicity for older cancer patients. We mapped and summarized the available evidence on the integration of geriatric assessment into clinical oncology practice, and ascertained which domains have been implemented. We systematically searched bibliographic databases and trial registries for reports of clinical studies, clinical practice guidelines, systematic and non-systematic reviews, and grey literature published in English. We gathered data on study characteristics, geriatric domains and strategies evaluated, and relevant study objectives and findings. From a total of 10,124 identified citations, 38 articles met our eligibility criteria, 3 of which were clinical practice guidelines. Nearly half of these articles came from the United States. Domains of the geriatric assessment implemented in studies ranged from 1 to 12, with varied combinations. We identified 27 studies on strategies for implementing geriatric assessment and 24 studies on feasibility of implementing geriatric assessment, into clinical oncology practice. We also identified 3 main geriatric assessment models: 2 from the United States and 1 from Australia. Furthermore, we identified 2 reviews that reported varied components of geriatric assessment models. There is increasingly robust evidence to implement formal geriatric assessment in oncology practice. There remains a great deal of variation in the tools recommended to address each of the domains in a geriatric assessment, with only 1 guideline (American Society of Clinical Oncology guideline) settling on a specific best practice.Protocol registration: Open Science Framework osf.io/mec93.  相似文献   
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PI has been rarely reported following pediatric live‐related liver transplantation. Such a disorder is characterized by accumulation of gas in the bowel wall. The cause of PI has not been yet established; however, it has been strongly linked with steroid therapy. In this report, we present a case of PI following pediatric live‐related liver transplantation that has been successfully managed conservatively.  相似文献   
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Background

The assessment of arterial stiffness is increasingly used for evaluating patients with different cardiovascular diseases as the mechanical properties of major arteries are often altered. Aortic stiffness can be noninvasively estimated by measuring pulse wave velocity (PWV). Several methods have been proposed for measuring PWV using velocity-encoded cardiovascular magnetic resonance (CMR), including transit-time (TT), flow-area (QA), and cross-correlation (XC) methods. However, assessment and comparison of these techniques at high field strength has not yet been performed. In this work, the TT, QA, and XC techniques were clinically tested at 3 Tesla and compared to each other.

Methods

Fifty cardiovascular patients and six volunteers were scanned to acquire the necessary images. The six volunteer scans were performed twice to test inter-scan reproducibility. Patient images were analyzed using the TT, XC, and QA methods to determine PWV. Two observers analyzed the images to determine inter-observer and intra-observer variabilities. The PWV measurements by the three methods were compared to each other to test inter-method variability. To illustrate the importance of PWV using CMR, the degree of aortic stiffness was assessed using PWV and related to LV dysfunction in five patients with diastolic heart failure patients and five matched volunteers.

Results

The inter-observer and intra-observer variability results showed no bias between the different techniques. The TT and XC results were more reproducible than the QA; the mean (SD) inter-observer/intra-observer PWV differences were -0.12(1.3)/-0.04(0.4) for TT, 0.2(1.3)/0.09(0.9) for XC, and 0.6(1.6)/0.2(1.4) m/s for QA methods, respectively. The correlation coefficients (r) for the inter-observer/intra-observer comparisons were 0.94/0.99, 0.88/0.94, and 0.83/0.92 for the TT, XC, and QA methods, respectively. The inter-scan reproducibility results showed low variability between the repeated scans (mean (SD) PWV difference = -0.02(0.4) m/s and r = 0.96). The inter-method variability results showed strong correlation between the TT and XC measurements, but less correlation with QA: r = 0.95, 0.87, and 0.89, and mean (SD) PWV differences = -0.12(1.0), 0.8(1.7), and 0.65(1.6) m/s for TT-XC, TT-QA, and XC-QA, respectively. Finally, in the group of diastolic heart failure patient, PWV was significantly higher (6.3 ± 1.9 m/s) than in volunteers (3.5 ± 1.4 m/s), and the degree of LV diastolic dysfunction showed good correlation with aortic PWV.

Conclusions

In conclusion, while each of the studied methods has its own advantages and disadvantages, at high field strength, the TT and XC methods result in closer and more reproducible aortic PWV measurements, and the associated image processing requires less user interaction, than in the QA method. The choice of the analysis technique depends on the vessel segment geometry and available image quality.  相似文献   
109.
Vascular endothelial growth factor (VEGF) is a potent growth factor that is indispensable for the development of blood vessels in the fetus and for wound healing in adults. VEGF likely plays a role in maintaining the blood vessels once they have been formed. It is not clear, however, whether a low tissue VEGF (caused either by disease or by systemic administration of VEGF antagonists) can cause abnormalities in preexisting blood vessels, especially of wound tissue that requires high local levels of VEGF for healing. The present study investigated the effect of VEGF antagonism on blood vessels of foreign-body granulomas (a model of wound-healing tissue). Granulomas were induced by implanting perforated polyvinyl tubes into the subcutaneous tissue of rats and allowed to develop for 14 days, at which time the implanted tubes were completely encapsulated by the subcutaneous tissue. The encapsulated granulomas consisted of 3 distinct histological layers, of which the middle layer was well perfused by a rich supply of microvessels. Morphologically, the granuloma remained "stable" after developing for 14 days. At 1 week, VEGF levels in the granuloma fluid, which is in equilibrium with the interstitial fluid, were 25 times higher than in the plasma. VEGF levels in the granuloma fluid continued to increase for up to 3 weeks, reflecting the high dependence of the wound tissue on ambient VEGF levels. After injection of the VEGF receptor antagonist in the fully formed granuloma, the preexisting blood vessels in the middle layer regressed and underwent apoptosis, accompanied by expansion of the extracellular matrix (predominately collagen I) into areas normally devoid of matrix. We conclude that wound tissue is sensitive to ambient VEGF levels, and that a low VEGF condition resulting from VEGF receptor antagonism can disrupt the healing of wound tissue.  相似文献   
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