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The aim of this study was to determine the biodistribution and tumor targeting ability of (14)C-labeled 3-bromopyruvate ([(14)C]3-BrPA) after i.a. and i.v. delivery in the VX2 rabbit model. In addition, we evaluated the effects of [(14)C]3-BrPA on tumor and healthy tissue glucose metabolism by determining (18)F-deoxyglucose (FDG) uptake. Last, we determined the survival benefit of i.a. administered 3-BrPA. In total, 60 rabbits with VX2 liver tumor received either 1.75 mM [(14)C]3-BrPA i.a., 1.75 mM [(14)C]3-BrPA i.v., 20 mM [(14)C]3-BrPA i.v., or 25 ml of phosphate-buffered saline (PBS). All rabbits (with the exception of the 20 mM i.v. group) received FDG 1 h before sacrifice. Next, we compared survival of animals treated with i.a. administered 1.75 mM [(14)C]3-BrPA in 25 ml of PBS (n = 22) with controls (n = 10). After i.a. infusion, tumor uptake of [(14)C]3-BrPA was 1.8 +/- 0.2% percentage of injected dose per gram of tissue (%ID/g), whereas other tissues showed minimal uptake. After i.v. infusion (1.75 mM), tumor uptake of [(14)C]3-BrPA was 0.03 +/- 0.01% ID/g. After i.a. administration of [(14)C]3-BrPA, tumor uptake of FDG was 26 times lower than in controls. After i.v. administration of [(14)C]3-BrPA, there was no significant difference in tumor FDG uptake. Survival analysis showed that rabbits treated with 1.75 mM 3-BrPA survived longer (55 days) than controls (18.6 days). Intra-arterially delivered 3-BrPA has a favorable biodistribution profile, combining a high tumor uptake resulting in blockage of FDG uptake with no effects on healthy tissue. The local control of the liver tumor by 3-BrPA resulted in a significant survival benefit.  相似文献   
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Modification of a biomedical-grade stainless steel 316LS surface by electrochemical cyclic potentiodynamic passivation (CPP) and the response of fibrinogen (Fg), platelets, endothelial cells (ECs) and smooth muscles cells (SMCs) to this surface was investigated. Polarization modulation infrared reflection absorption spectroscopy revealed a significant difference between the secondary structure of Fg adsorbed on the unmodified and CPP surface, the latter being closer to that of native Fg. This was postulated as the origin of the significantly lower surface density of attached platelets on the CPP surface. The competitive interaction of ECs and SMCs with the surface showed that the ECs/SMCs surface density ratio is significantly higher on the CPP surface over the first 2 h of attachment, suggesting faster initial attachment kinetics of ECs on the CPP surface. The presented results thus clearly demonstrate an increase in biocompatibility of the CPP 316LS surface.  相似文献   
64.

Aim  

F-18 fluor choline-positron emission tomography/computed tomography (FCH-PET/CT) has emerged as a new diagnostic tool for the imaging of prostate cancer. In this study, we have evaluated the potential role of FCH-PET/CT for the assessment of bone metastases in patients with prostate cancer. Furthermore, we assessed the pattern of metabolic uptake by FCH in relation to morphologic changes on CT.  相似文献   
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OBJETIVE: To study the analgesia, hemodynamic stability and inflammatory response in patients undergoing carotid endarterectomy under different types of general anesthesia. MATERIALS AND METHODS: A comparison of 80 patients randomized to 4 groups: group 1, maintenance with sevoflurane at a minimum alveolar concentration (MAC) of 1; group 2, sevoflurane at MAC 1.5; group 3, remifentanil; group 4, propofol. Variables studied were hemodynamic alterations during and after surgery, level of postoperative analgesia, differential white cell counts, levels of interleukin-6 (IL-6), and clinical signs and symptoms of systemic inflammatory response syndrome in the first 24 hours after surgery. RESULTS: The incidences of episodes of intraoperative hypertension were 60% in group 1, 65% in group 2, 50% in group 3, and 60% in group 4. The incidences of episodes of intraoperative hypotension were 85% in group 1, 80% in group 2, 80% in group 3, and 75% in group 4. Patients in groups 3 and 4 had higher incidences of systemic inflammatory response syndrome (p<0.05) in the first 24 hours after surgery and higher levels of IL-6 (p<0.05). Postoperative analgesia was similar in all 4 groups. CONCLUSIONS: Increased levels of IL-6 in peripheral blood and of systemic inflammatory response syndrome were found in the early postoperative period in groups that did not receive halogenated gases. Hemodynamic stability and analgesia were similar in all groups, however.  相似文献   
68.
Squamous cell carcinoma of the head and neck is the most common epithelial neoplasm of the upper aerodigestive tract and represents a major health concern in the United States and worldwide. Invasive squamous cell carcinoma is the end result of a multiyear, multistep process of accumulation of genetic and phenotypic damage. Chemoprevention is defined as the use of pharmacologic or natural agents that inhibit the development of invasive cancer whether by blocking the DNA damage that initiates carcinogenesis or by arresting or reversing the progression of premalignant cells in which such damage has already occurred. Chemoprevention is widely recognized as an important area of research in head and neck cancer. This article reviews the field of chemoprevention and recent advances in molecular epidemiology and genetics. Current clinical trials are described.  相似文献   
69.
This article reviews the history of legal steps which led to conflicting regulatory approaches to the use of asbestos between the EU, the US and the rest of the world. Particular attention is paid to the EU ruling out the use of all types of asbestos. The author criticizes how the Scientific Committee on Toxicity, Ecotoxicity and the Environment of the European Commission altered their own opinion within as short a time as seven months, and points out the weaknesses of the scientific justification for the EU ban. With equal criticism the author addresses the weak scientific rationale on which Collegium Ramazzini founds its call for an immediate and total international ban of the mining and use of all types of asbestos.  相似文献   
70.
Microbial coinfections can increase the morbidity and mortality rates of viral respiratory diseases. Therefore, this study aimed to determine the pooled prevalence of fungal coinfections in coronavirus disease 2019 (COVID-19) patients. Web of Science, Medline, Scopus, and Embase were searched without language restrictions to identify the related research on COVID-19 patients with fungal coinfections from December 1, 2019, to December 30, 2020. A random-effects model was used for analysis. The sample size included 2,246 patients from 8 studies. The pooled prevalence of fungal coinfections was 12.60%. The frequency of fungal subtype coinfections was 3.71% for Aspergillus, 2.39% for Candida, and 0.39% for other. The World Health Organization’s Regional Office for Europe and Regional Office for Southeast Asia had the highest (23.28%) and lowest (4.53%) estimated prevalence of fungal coinfection, respectively. Our findings showed a high prevalence of fungal coinfections in COVID-19 cases, which is a likely contributor to mortality in COVID-19 patients. Early identification of fungal pathogens in the laboratory for COVID-19 patients can lead to timely treatment and prevention of further damage by this hidden infection.  相似文献   
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