Purpose: To assess the feasibility, image quality, and radiation dose of computed tomography (CT) renal perfusion imaging in the adaptive 4-dimensional (4D)-spiral mode in patients with renal cell carcinoma (RCC), and to compare quantitative measurements between 2-dimensional regions-of-interest (2D-ROI) and 3-dimensional volumes-of-interest (3D-VOI).
Materials And Methods: Twenty-one patients (13 male; age, 67.4 ± 9.
This is a review of minimally invasive therapy options for liver tumors, such as highly focused ultrasound, microwave ablation, and irreversible electroporation, as well as new aspects of radiofrequency ablation. Radiofrequency ablation is recommended for patients with early-stage HCC with up to 3 lesions with a tumor diameter within 3 cm and for patients with non-resectable liver metastasis. Indications and contraindications to treatment are designated, and different modalities for image-based therapy guidance are compared.
View Article and Find Full Text PDFPurpose: To evaluate long-term effectiveness of magnetic resonance (MR)-guided radiofrequency (RF) ablation of hepatocellular carcinoma (HCC).
Materials And Methods: This prospective study was approved by the institutional review board. In 20 patients, 28 HCCs (mean diameter, 28.
Due to their adjuvant effect and their ability to chaperone tumor-associated peptides, heat shock proteins constitute a potent alarm signal for the immune system and can lead to activation of anti-tumor T-cell immunity. Radiofrequency ablation has been reported to induce heat shock protein expression especially that of heat shock protein 70 in sublethally damaged tumor cells. In this study, we evaluated the release of heat shock protein 70 into the serum of cancer-bearing patients directly after radiofrequency ablation.
View Article and Find Full Text PDFObjective: The aim of this pilot study was to test and demonstrate the feasibility of simultaneous positron emission tomography (PET) and magnetic resonance imaging (MRI) of the head and upper neck area using a new hybrid PET/MRI system.
Methods: Eight patients with malignant head and neck tumours were included in the pilot study. Directly after routine PET/CT imaging with a whole-body system using the glucose derivative 2-[¹⁸F]fluoro-2deoxy-D-glucose (FDG) as a radiotracer additional measurements were performed with a prototype PET/MRI system for simultaneous PET and MR imaging.
Int J Radiat Oncol Biol Phys
September 2011
Purpose: To evaluate intensity-modulated radiotherapy (IMRT) treatment planning based on simultaneous positron-emission tomography and magnetic resonance imaging (PET/MRI) of meningioma.
Methods And Materials: A meningioma patient was examined prior to radiotherapy with dedicated planning computed tomography (CT), MRI, PET/CT with gallium-68-labeled DOTATOC (68Ga-DOTATOC), and simultaneous 68Ga-DOTATOC-PET/MRI. The first gross target volume (GTV) was defined based on a combination of separate MR and 68Ga-DOTATOC-PET/CT imaging (GTVPET/CT+MR).
Background & Aims: High protein diets have been shown to improve hepatic steatosis in rodent models and in high-fat fed humans. We therefore evaluated the effects of a protein supplementation on intrahepatocellular lipids (IHCL), and fasting plasma triglycerides in obese non diabetic women.
Methods: Eleven obese women received a 60 g/day whey protein supplement (WPS) for 4-weeks, while otherwise nourished on a spontaneous diet, IHCL concentrations, visceral body fat, total liver volume (MR), fasting total-triglyceride and cholesterol concentrations, glucose tolerance (standard 75 g OGTT), insulin sensitivity (HOMA IS index), creatinine clearance, blood pressure and body composition (bio-impedance analysis) were assessed before and after 4-week WPS.
In an era when healthcare organizations are beset by intense competition, lawsuits, and increased administrative costs, it is essential that employees perform their jobs efficiently and without distraction. Deviant workplace behavior among healthcare employees is especially threatening to organizational effectiveness, and healthcare managers must understand the antecedents of such behavior to minimize its prevalence. Deviant employee behavior has been categorized into two major types, individual and organizational, according to the intended target of the behavior.
View Article and Find Full Text PDFUsing Hollander's (1958) idiosyncrasy credit theory of leadership as the theoretical backdrop, we examined when and why organizational leaders escape punitive evaluation for their organizational transgressions. In a sample of 162 full-time employees, we found that leaders who were perceived to be more able and inspirationally motivating were less punitively evaluated by employees for leader transgressions. These effects were mediated by the leaders' LMX (leader-member exchange) with their employees.
View Article and Find Full Text PDFBackground: Determination of glomerular filtration rate (GFR) using plasma disappearance curves requires the injection of a filtration marker and repeated timed blood collections. Gadolinium-containing contrast media are excreted exclusively by glomerular filtration and could provide a novel approach to quantifying GFR using magnetic resonance (MR) imaging. The aim of this study was to demonstrate the feasibility of measuring GFR by the clearance of gadolinium-containing contrast medium in patients with chronic kidney disease (CKD).
View Article and Find Full Text PDFObjective: Intramyocellular acetylcarnitine (IMAC) is involved in exercise-related fuel metabolism. It is not known whether levels of systemic glucose influence IMAC levels in type 1 diabetes.
Research Design And Methods: Seven male individuals with type 1 diabetes performed 120 min of aerobic exercise at 55-60% of Vo(2max) randomly on two occasions (glucose clamped to 5 or 11 mmol/l, identical insulinemia).
Objective: The purpose of this essay is to provide a practical review of the spectrum of morphologic and functional MRI findings in psoriatic arthritis of the hand joints.
Conclusion: The MRI findings of psoriatic arthritis include enthesitis, bone marrow edema, and periostitis accompanying articular or flexor tendon sheath synovitis in the early stage accompanied by destructive and proliferative bony changes, subluxation, and ankylosis in the late stage.
Biopharm Drug Dispos
October 2010
The clinical assessment of new formulations of human insulin is problematic due to the inability to distinguish between endogenous insulin and exogenously administered insulin. The usual methods to surmount the problem of distinguishing between endogenous and exogenous human insulin include evaluation in subjects with no or little endogenous insulin, hyper-insulinemic clamp studies or the administration of somatostatin to suppress endogenous insulin secretion. All of these methods have significant drawbacks.
View Article and Find Full Text PDFRadiofrequency (RF) ablation is a minimally invasive technique routinely applied for the treatment of primary and secondary liver tumors. It induces cell death by thermal coagulative necrosis of tumor tissues, whereas cellular metabolism can still take place in a transition zone surrounding the necrotic area. An increase in heat shock protein expression occurs shortly after treatment, suggesting that the induction of activating signals may stimulate the host immune system.
View Article and Find Full Text PDFUnlabelled: Simultaneous PET and MRI using new hybrid PET/MRI systems promises optimal spatial and temporal coregistration of structural, functional, and molecular image data. In a pilot study of 10 patients with intracranial masses, the feasibility of tumor assessment using a PET/MRI system comprising lutetium oxyorthosilicate scintillators coupled to avalanche photodiodes was evaluated, and quantification accuracy was compared with conventional PET/CT datasets.
Methods: All measurements were performed with a hybrid PET/MRI scanner consisting of a conventional 3-T MRI scanner in combination with an inserted MRI-compatible PET system.
Background: Insulin therapy is often a delayed strategy in patients with type 2 diabetes mellitus because it is associated with weight gain, hypoglycaemia, and the need for subcutaneous injections. We aimed to assess the efficacy and safety of prandial Technosphere inhaled insulin compared with twice daily biaspart insulin.
Methods: In this randomised, open-label, parallel-group study, adult patients with type 2 diabetes mellitus and poor glycaemic control despite insulin therapy, with or without oral antidiabetes drugs, were enrolled from ten countries between Feb 23, 2006, and Aug 8, 2007.
MKC253 is glucagon-like peptide 1 (GLP-1, 7-36 amide) adsorbed onto Technosphere microparticles for oral inhalation. The pharmacokinetics of inhaled GLP-1 and the pharmacokinetic-pharmacodynamic (PK-PD) relationship between inhaled GLP-1 and insulin were analyzed in two trials, one in healthy normal volunteers and the other in patients with type 2 diabetes. Inhaled GLP-1 was absorbed quickly, with peak concentrations occurring within 5 min, and levels returned to baseline within 30 min.
View Article and Find Full Text PDFIntroduction of high-field-strength whole-body MR scanners to clinical routine made abdominal magnetic resonance (MR) imaging widely available. Higher field strength provides improved signal yield, but other issues such as shorter wavelength and increased power deposition of radiofrequency in tissue must also be taken into account. This review describes current problems and future opportunities of abdominal MR imaging at 3.
View Article and Find Full Text PDFPurpose: Principles of magnetic resonance imaging techniques providing perfusion-related contrast weighting without administration of contrast media are reported and analysed systematically. Especially common approaches to arterial spin labelling (ASL) perfusion imaging allowing quantitative assessment of specific perfusion rates are described in detail. The potential of ASL for perfusion imaging was tested in several types of tissue.
View Article and Find Full Text PDFPurpose: The aim of this study was to test and demonstrate the feasibility of diffusion tensor imaging (DTI) with a hybrid positron emission tomography (PET)/magnetic resonance imaging system for simultaneous PET and magnetic resonance (MR) data acquisition.
Materials And Methods: All measurements were performed with a prototype hybrid PET/MR scanner dedicated for brain and head imaging. The PET scanner, which is inserted into a conventional 3.
Purpose: To provide a longer follow-up after strabismus surgery for secondary sensory strabismus.
Patients And Methods: We investigated the follow up of 26 patients operated on for secondary strabismus: 7 convergent (SSC), 19 divergent (SSD). Inclusion criteria were fellow eye without any morphological disorder, and exclusion criteria were possible motility disorders or mechanical restriction: The mean follow-up time after surgery was 5 years 8 months +/- 4 years (1 year 8 months to 12 years 8 months) for SSC and 5 years 10 months +/- 3 years, 8 months (7 months to 13 years 3 months) for SSD, with p = 0.
Background: Evaluation of potential kidney donors requires the assessment of both kidney anatomy and function. In this prospective study, we sought to expand the diagnostic yield of magnetic resonance (MR) by adding functional measurements of glomerular filtration rate (GFR) and split renal function.
Methods: Between 2007 and 2009, all potential kidney donors presenting to our facility underwent a comprehensive single-stop MR study that included an assessment of anatomy, angiography and functional measurements.
The Kepler mission was designed to determine the frequency of Earth-sized planets in and near the habitable zone of Sun-like stars. The habitable zone is the region where planetary temperatures are suitable for water to exist on a planet's surface. During the first 6 weeks of observations, Kepler monitored 156,000 stars, and five new exoplanets with sizes between 0.
View Article and Find Full Text PDFEndurance training improves exercise performance and insulin sensitivity, and these effects may be in part mediated by an enhanced fat oxidation. Since n-3 and n-9 unsaturated fatty acids may also increase fat oxidation, we hypothesised that a diet enriched in these fatty acids may enhance the effects of endurance training on exercise performance, insulin sensitivity and fat oxidation. To assess this hypothesis, sixteen normal-weight sedentary male subjects were randomly assigned to an isoenergetic diet enriched with fish and olive oils (unsaturated fatty acid group (UFA): 52 % carbohydrates, 34 % fat (12 % SFA, 12 % MUFA, 5 % PUFA), 14 % protein), or a control diet (control group (CON): 62 % carbohydrates, 24 % fat (12 % SFA, 6 % MUFA, 2 % PUFA), 14 % protein) and underwent a 10 d gradual endurance training protocol.
View Article and Find Full Text PDFA recent report of the feasibility of simultaneous PET/MR imaging of the healthy human brain has sparked excitement in the field of neuroimaging because of its potential influence and utility in clinical neuroscience research. The aim of this communication is to discuss the benefits and current drawbacks of the hybrid imaging system and to highlight some perspectives of the new technique for brain neoplasms.
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