Search results for "ISOTOPE"

Strontium90 for determination of time since death

1999

Strontium90 (Sr90) is an artificial nuclear fission product of the atmospheric a-bomb testing between 1945 and 1979. It was spread throughout the atmosphere in the following years. Sr90 is an analogue to calcium and therefore enriched in human bones. Several studies especially in the 1960s and 1970s were undertaken to investigate the Sr90 burden and the resulting incorporated radiation in humans, but present studies are missing. In this study nine bone samples, three from 1931/32 and six from 1989 to 1994 were examined by measuring the Sr90 radiation. The samples from 1931/32 did not show any Sr90 activity. All the samples from 1989 and later showed a Sr90 activity, but the intensity was ve…

Effect of radiosynoviorthesis on the progression of arthropathy and haemarthrosis reduction in haemophilic patients.

2017

IntroductionRepeated haemarthrosis is widely accepted as the triggering cause of synovitis and haemophilic arthropathy. A first-line treatment of chronic synovitis is radiosynoviorthesis (RS). The aim of this study was to evaluate the RS effects on the progression of arthropathy and on a reduction in bleeding in patients with haemophilia. MethodsAn observational-retrospective study was performed. Bleeding episodes in the 12months following and in the 12months preceding RS was compared. The arthropathy was clinically and radiologically analysed by age range, joint and subject, comparing those undergoing RS (Radiosynoviorthesis Group, RSG) against those not undergoing this treatment (Non-Radi…

Diagnostic radiological examinations and risk of intracranial tumours in adults—findings from the Interphone Study

2021

Abstract Background Exposure to high doses of ionizing radiation is among the few well-established brain tumour risk factors. We used data from the Interphone study to evaluate the effects of exposure to low-dose radiation from diagnostic radiological examinations on glioma, meningioma and acoustic neuroma risk. Methods Brain tumour cases (2644 gliomas, 2236 meningiomas, 1083 neuromas) diagnosed in 2000–02 were identified through hospitals in 13 countries, and 6068 controls (population-based controls in most centres) were included in the analysis. Participation across all centres was 64% for glioma cases, 78% for meningioma cases, 82% for acoustic neuroma cases and 53% for controls. Informa…

Fetal dose measurements and shielding efficiency assessment in a custom setup of (192)Ir brachytherapy for a pregnant woman with breast cancer.

2015

To assess the radiation dose to the fetus of a pregnant patient undergoing high-dose-rate (HDR) (192)Ir interstitial breast brachytherapy, and to design a new patient setup and lead shielding technique that minimizes the fetal dose.Radiochromic films were placed between the slices of an anthropomorphic phantom modeling the patient. The pregnant woman was seated in a chair with the breast over a table and inside a leaded box. Dose variation as a function of distance from the implant volume as well as dose homogeneity within a representative slice of the fetal position was evaluated without and with shielding.With shielding, the peripheral dose after a complete treatment ranged from 50 cGy at…

Constraints on mantle source and interactions due to He-Ar isotope variations in Marsili seamount and eastern Aeolian Volcanic Arc (Panarea and Strom…

2011

Gel Electrophoresis Coupled to Inductively Coupled Plasma−Mass Spectrometry Using Species-Specific Isotope Dilution for Iodide and Iodate Determinati…

2007

In this paper, we present an online coupling of gel electrophoresis (GE) and inductively coupled plasma-mass spectrometry (ICP-MS) for the determination of iodine species (iodide and iodate) in liquid (seawater) and aerosol samples. For the first time, this approach is applied to the analysis of small molecules, and initial systematic investigations revealed that the migration behavior as well as the detection sensitivity strongly depends on the matrix (e.g., high concentrations of chloride). These effects could consequently affect the accuracy of analytical results, so that they need to be considered for the analysis of real samples. The technique used for quantification is species-specifi…

Uran aus deutschen Nuklearprojekten der 1940er Jahre – eine nuklearforensische Untersuchung

2015

Wir berichten hier uber eine nuklearforensische Analyse verschiedener Uranmaterialien aus deutschen Nuklearprojekten der 1940er Jahre, bei denen Uranmetall in verschiedenen Geometrien verwendet wurde. Mithilfe des 230Th/234U-Isotopenverhaltnisses konnte fur das Metall ein Produktionszeitraum von 1940 bis 1943 bestimmt werden. Die geographische Herkunft des Urans wurde anhand des Spurengehalts an Seltenerdelementen und der Strontium-Isotopenverhaltnisse bestimmt. Die Ergebnisse zeigen, dass das bei den deutschen Nuklearprojekten verwendete Uran aus Minen in der Tschechischen Republik stammt. 236U und 239Pu wurden in Spuren nachgewiesen. Diese entsprechen in etwa der Haufigkeit dieser Isotope…

Reduced In Vivo Aortic Uptake of Radiolabeled Oxidation-Specific Antibodies Reflects Changes in Plaque Composition Consistent With Plaque Stabilizati…

2004

Objective— Labeled oxidation-specific antibodies (Ox-AB) detect, quantify, and noninvasively image lipid-rich atherosclerotic lesions. However, it is unknown whether Ox-AB detect plaque stabilization. Methods and Results— The aortic uptake of intravenously injected 125 I-MDA2 (Ox-AB to malondialdehyde [MDA]–low-density lipoprotein [LDL]) was quantitated in: (1) LDL receptor−/− mice with established atherosclerosis continued on Western diet (Progression) or switched to chow (Regression) or chow+vitamins E and C (Regression-VIT) for 6 months; and (2) Watanabe rabbits (3- to 57-months old) with naturally evolved atherosclerotic lesions. In mice, the Progression group had more extensive athero…

Influence of Duration of Experiment on Rate of Uptake of Radioactive Potassium in Smooth Muscle

1963

THE rates of uptake and loss of radioactive tracers by excitable tissues can often be described by a function involving one exponential term1–3, but over relatively long periods deviations have been observed from such a simple course4–7. The rates of exchange towards the end of such periods are commonly slower than would be predicted from the initial rates and two general causes for this behaviour have been suggested: either the rates are, in fact, diminishing during the course of an experiment or the tissue is not behaving uniformly. This latter possibility has been extensively investigated1,8–15, because biological material shows an obvious lack of uniformity, and because deviations from …

Opiate-induced dopamine release is modulated by severity of alcohol dependence: an [(18)F]fallypride positron emission tomography study.

2011

Background Preclinical data implicate the reinforcing effects of alcohol to be mediated by interaction between the opioid and dopamine systems of the brain. Specifically, alcohol-induced release of β-endorphins stimulates μ-opioid receptors (MORs), which is believed to cause dopamine release in the brain reward system. Individual differences in opioid or dopamine neurotransmission have been suggested to be responsible for enhanced liability to abuse alcohol. In the present study, a single dose of the MOR agonist remifentanil was administered in detoxified alcohol-dependent patients and healthy control subjects to mimic the β-endorphin-releasing properties of ethanol and to assess the effect…