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The conducting nanochannel is made up of poly(vinylidene fluoride) and its nanohybrid (NH) membrane through irradiation of high-energy (80 MeV) lithium ions followed by chemical etching. The NH is ...

The necessity to study the mechanisms of 90Sr behavior in ecosystems is conditioned by the radioactive contamination of the environment due to global fallout as a result of nuclear weapon tests, as well as incidents and accidents at radiation-hazardous facilities. The basic regularities of radionuclide behavior in soils and in the soil–agricultural plants system are described. The role of various factors affecting radionuclide migration in ecosystems is assessed. The key characteristics required for the parameterization of migration mathematical models used for predicting the radionuclide uptake by plants are presented.

Utility of 18F-FDG PET/CT in diagnosing infective endocarditis (IE) associated with cardiac implantable electronic devices (CIEDs) is not well established. Current ESC guidelines recommend the use of FDG-PET imaging in patients with CIEDs and positive blood cultures, but the number of studies evaluating the diagnostic performance of FDG-PET imaging in these patients remain limited. Our objective was to assess the diagnostic yield of 18F-FDG PET/CT in patients with suspected CIED infections, differentiating between pocket infection (PI) and lead infection (CIED-IE). From 2013 to 2018, all patients (n = 63) admitted to a hospital with suspected CIED infection were prospectively recruited, undergoing a diagnostic work-up including a PET/CT. Explanted devices and material from the pocket were cultured. 14 cases corresponded to isolated PI and 13 were categorized as CIED-IE. Considering radionuclide uptake in the intracardiac portion of the lead, sensitivity and specificity of PET/CT for CIED-IE were 38.5% and 98.0%, respectively. Positive (19.2) and negative (0.6) likelihood ratio values, suggest that a positive PET/CT is much more probable to correspond to a patient with CIED-IE, whereas it is not possible to exclude this diagnosis when negative. For PI, sensitivity and specificity were 72.2% and 95.6%, respectively. The yield of 18F-FDG PET/CT for suspected CIED infections differs depending on the site of infection. Due to very high specificity but poor sensitivity, negative studies must be interpreted with caution if the suspicion of CIED-IE is high.

Purpose. Technetium-99m diethylene triamine pentaacetic acid (Tc-99m DTPA) renal dynamic scintigraphy is a widely used imaging technique that evaluates renal function of patients with extrarenal abnormalities, but its clinical value in potentially offering us information on proliferation of liposarcoma has not yet been reported. Methods. We retrospectively reviewed 7 patients with histopathologically confirmed retroperitoneal liposarcoma who underwent Tc-99m DTPA renal dynamic scintigraphy. The clinical data, histopathological findings, Glomerular Filtration Rate (GFR), and Tc-99m DTPA uptake were recorded. Results. Dedifferentiated liposarcoma and well-differentiated liposarcoma showed dissimilar degrees of Tc-99m DTPA uptake, an observation that correlated with Ki-67 expression (p<0.01). 4 of the 7 patients were diagnosed with dedifferentiated liposarcoma, showing a moderate uptake of Tc-99m DTPA and greater than 20% Ki-67 expression on histological slides. Meanwhile, the remaining 3 patients, diagnosed with well-differentiated liposarcoma, showed no uptake of Tc-99m DTPA and Ki-67 expression of less than 5%. Conclusions. This study suggests that Tc-99m DTPA renal dynamic scintigraphy provides diagnostic value in patients with retroperitoneal liposarcoma, not only in evaluating renal function but also in visualizing lesion-related radionuclide uptake, which may potentially offer further clinical insights into tumor proliferation and provide prognostic value for clinical outcomes in patients with retroperitoneal liposarcoma.

Currently, the diagnosis of bone flap osteomyelitis (BFO) remains a challenge for medical imaging. The present study aimed to identify predictive scintigraphic patterns of BFO. This retrospective study reviewed planar bone scan of patients with suspected BFO between 2010, and 2016. A total of 15 patients were included. Final diagnosis of BFO was obtained by histological and bacteriological documentation. Eight scintigraphic signs potentially helpful were reviewed and correlated with the final diagnosis individually or in combination through Fischer exact test. Eight patients out of 15 (53.3%) were diagnosed with BFO. Radionuclide uptake inside the bone flap during blood-pool phase was predictive for BFO (p = 0.007) with 75.0% sensitivity 100% specificity, and 86.7% accuracy. In combination, radionuclide uptake inside the bone flap or a spreading wavefront between blood-pool and delayed phases was associated with BFO (p = 0.007). It did not improve diagnostic performance. Using well-defined and reproducible scintigraphic signs, bone scan is helpful for the diagnosis of BFO.

Nuclear scintigraphy can be beneficial in the investigation of equine lameness and poor performance. Images obtained through the sole allow for better identification of a region of increased radionuclide uptake in the foot. The presence of shoes or pads may affect these images. To determine the degree of radioactive attenuation different types of shoes and pads of different thickness and materials were evaluated by placing the material directly on the gamma camera detector acquiring flood images from a point source. The study compared five different types of shoes from 3 different shoeing materials, steel, aluminum, and polyurethane. This study also assessed 8 different types of pads that were selected based on the subjective densities and variable rigidity of the materials. All types of shoes/pads evaluated caused some degree of attenuation (P < 0.05). Steel shoes of all types cause the most attenuation (54%), followed by aluminum shoes (22%), and the shoes or pads composed primarily of a plastic polymer cause the least amount of attenuation (15%). The results of the study found that pads or shoes cause significant (p < 0.05) attenuation of gamma radiation. Composition, thickness and density characterized mass absorption coefficient, of the material affect the amount of gamma radiation attenuation. Because of the attenuation of gamma radiation, we recommend shoes and pads be removed prior to nuclear scintigraphic examination of the front foot if a solar image is desired, as this attenuation may affect image quality.

Gallium-68 (Ga)-PSMA and F-Choline are two radionuclides that have already shown high potential for the detection of prostate cancer. The comparison between these two radionuclides has several advantages in radiation protection. The aim of this prospective study was to identify which of these two radionuclides can help in predicting the equivalent dose using the maximum standard uptake value (SUVmax) of normal organs, the kidneys. Two groups of 40 patients (total n = 80) who underwent PET/CT using Ga or F for diagnosis of prostate cancer between April 2018 and December 2018 at the American University of Beirut Medical Center were included. First, the dose rates were measured after 1 h of radionuclide uptake at 1 m distance with background of 0.015 μSv h. Then, SUVmax for kidneys were determined from images obtained with PET/CT 1 h after injection of both radionuclides. The ratios of the equivalent doses to the SUVmax for kidneys were compared for both Ga-PSMA and F-Choline. There is a positive moderate relationship between the SUVmax for kidneys and the Ga dose rate after 1 h of injection at 1 m distance from the abdomen (p-value = 0.0230.05). This relationship is statistically significant. However, there is a very low negative relationship between the SUVmax kidney and F dose rate after 1 h of injection at 1 m distance from the abdomen (p-value = 0.930.05). This relationship is not statistically significant. This leads to the suggestion that we can predict the equivalent dose due to Ga by indicating the SUVmax from the PET/CT images.

The goal of this study is to shed more light on the influence of fertilisation on radionuclide transfer from soil to crops, which is a significant ecological issue in present-day agriculture due to the intensive use of soil amendments. Research on this subject has not been extensive, hence there are still numerous open questions that require an interdisciplinary approach involving agroecology and radioecology. Maize was chosen for our investigation because it has been used, in considerable quantities and worldwide, as both food and feed, which makes it part of numerous food chains with humans as final consumers. The agricultural part of the experiment was carried out on an acidic soil in northwestern Croatia, and it was based on seven treatments with different levels of NPK fertilisation. Radionuclide activity concentrations in sampled soil, stem, and grain were measured by means of high-resolution γ-ray spectrometry. We found that the radiological properties of the soil were not affected by the addition of the fertiliser. Soil-to-stem uptake for radionuclides of the whole 232Th decay chain was first suppressed by mild fertilisation, and then, at higher fertiliser concentrations, it stayed low and became independent of fertilisation level. The same effect was observed for the 238U decay chain before gaseous 222Rn. We present arguments in favour of the cause of the observed suppression being radionuclide complexation with constituents of the fertiliser. However, the concentration of 210Pb in stem did not depend on fertilisation, which was most probably a consequence of the decay of airborne 222Rn and the deposition of its progenies onto stem. Radionuclide translocation from stem to grain did not depend on fertilisation either, and it was appreciable only for 40K and 137Cs. In grain, radionuclide concentrations were lower than in stem. Overall, in our case, fertilisation had positive effects, reducing the presence of radionuclides in the maize while having no detectable impact on the radiological properties of the soil. This finding may have implications for future work, especially regarding concerns about the impact of soil amendments on food production.

The monitoring inspection of food after the Fukushima nuclear accident (2011) was essential for ensuring food safety in Japan and reducing the adverse health effects due to incorporation of inacceptable amounts of radionuclides, in particular radiocesium (134Cs and 137Cs). In this study, the mushroom fraction of the governmental data set of the first 5 years after the accident has been analyzed for contamination levels in mushrooms, in particular time trends and radioecological characteristics as well as associated health risks. The analyses show that mycorrhiza mushrooms are much more sensitive for radionuclide uptake than saprobiontic mushrooms (the latter of which include the very popular shiitake mushrooms (Lentinula edodes)). The maximum value reached 31,000 Bq/kg in a sample of apricot milkcaps in 2012. Analysis of the origin of the samples revealed that the origin (in terms of prefecture) of the mushrooms was a less determining factor for the contamination level than the type of mushrooms, as most exceedances in 2012 and thereafter were found outside Fukushima Prefecture. Several dose models were applied to the data to evaluate both worst case and realistic effective committed dose scenarios. The doses were generally rather low due to low consumption rates in the Japanese food basket. In any case, the analysis proved that the food monitoring campaign was highly effective in cutting doses to the public by more than a factor of 10 compared with a hypothetical scenario in which no monitoring had been conducted.

Purpose of review Congenital hypothyroidism is a common worldwide condition. Due in part to increasingly widespread newborn screening, the number of patients with this diagnosis is increasing. In this review, we discuss currently available imaging techniques and the benefits and limitations of these techniques in evaluating congenital hypothyroidism. Recent findings Recent work has demonstrated an increasing diagnosis of congenital hypothyroidism with normally located glands and mildly decreased thyroid function. Increasingly more genetic abnormalities have been recognized in the hormone synthesis pathways. These cases may have lower or shorter term treatment requirements than the more common severe forms of congenital hypothyroidism, and the ability to distinguish between these situations may become increasingly more important to management and counseling. Summary Imaging studies for congenital hypothyroidism may be unlikely to change immediate management in the majority of cases. The common modalities of imaging include thyroid ultrasound and radionuclide uptake scanning with either technetium or iodine. These can help establish an etiology for the condition, and in less-common causes of congenital hypothyroidism may have implications on treatment decisions, prognosis, and counseling.

Positron emission tomography (PET) is a diagnostic imaging modality in nuclear medicine. The most common radionuclide in PET is 18F fluoro deoxyglucose (FDG). In this study we used the information on radionuclide uptake from PET images and software to make an estimation of effective dose received by patients during 18F-FDG PET examination. We analysed data from 50 patients who performed positron emission tomography—computed tomography (PET-CT) examination. Uptake values were collected in bladder, bones, heart wall, kidneys, liver, brain and remainder. Using a simplified biokinetic model, residence time was calculated and used as an input parameter in OLINDA/EXM® software package. The conversion factor from administered activity to effective dose was found to be \( 0.016\frac{{{\text{mSv}}}}{{{\text{MBq}}}} \), which is only 15% less then value found in literature. The method described in the paper might be suitable in situations when standard calculation models are not adequate.

In the routine evaluation of the thyroid, imaging is often a useful modality, which gives anatomical and functional characteristics that can aid diagnosis. Thyroid ultrasonography is the principal imaging modality in this regard, whereas CT, MRI and PET scanning are much less frequently ordered for thyroid assessment through thyroid lesions are often discovered via such advanced imaging modalities as incidental findings.1 Unlike radiologists, most physicians tend to be unfamiliar with radiological features of thyroid disorders detected via these latter forms of scanning.2 A 25-year-old woman who was otherwise overtly healthy and asymptomatic without any history of medical illnesses or chronic medications had volunteered for a research study on brown fat. She underwent whole-body 18F-FDG PET/MR imaging according to a standard protocol. This unexpectedly revealed abnormally increased FDG uptake (SUVmax=6.84) over the anterior neck strangely reminiscent of typical radionuclide (99m Tc or 131I) thyroid scans of hyperthyroidism (figure …

Drinking Water Treatment Plants (DWTPs) can be optimised for removal of natural radionuclides, thus meeting EU legislation. Removed radionuclides (234,238U, 226Ra and 210Po) go into sludges. What would happen if these sludges were used in agriculture? Wheat plantlets were cultivated in original and sludge-amended soils under laboratory controlled conditions. Soil-to plant transfer was significantly increased in factors ranging 1.2–3.7, 2.0–5.6, and 1.6–2.4 for 234,238U, 226Ra and 210Po, respectively. The additional input was preferentially accumulated in roots.

Purpose: In addition to gamma radiation, 99mTc emits low-energy Auger electrons with path-lengths of nanometers to micrometers that cannot be utilized for diagnostic procedures; however, they have frequently been discussed for therapeutic applications. We compared radiotoxicity of three 99mTc-labeled radiopharmaceuticals with differences in the subcellular distribution.Materials and methods: The intracellular radionuclide uptake and subcellular distribution of [99mTc]-pertechnetate (99mTc-pertechnetate), [99mTc]Tc-hexamethyl-propylene-aminoxime (99mTc-HMPAO) and [99mTc]Tc-hexakis-2-methoxyisobutylisonitrile (99mTc-MIBI) were quantified in rat thyroid FRTL-5 cells. Radiotoxicity was compared using late phosphorylated histone H2AX (γH2AX) foci as a marker for unrepaired DNA double-strand breaks (DNA-DSB) and clonogenic cell survival.Results: 99mTc-HMPAO showed a substantially higher uptake into the nucleus and the membrane/organelles than 99mTc-pertechnetate or 99mTc-MIBI. The colony-forming assay s...

Background : Local ablave treatments play an important role for paents who cannot be treated surgically. Radiofrequency ablaon is a well-established alternave to surgical treatment of thyroid nodules, however it also has disadvantages. Microwave ablaon (MWA) is a new minimally invasive treatment promising several improvements. The aim of this retrospecve study was to evaluate the effects of microwave ablaon on thyroid nodules by 99m Tc-pertechnetate and 99m Tc-MIBI scingraphy. Materials and Methods : 30 paents with overall 40 nodules were treated. For the ablaon of thyroid nodules, a microwave generator working with frequencies from 902 to 928 MHz was used. The ablaonme ranged between 120 and 300 seconds per ablaon zone. The target temperatures ranged between 60-80 °C. Pre- and post- intervenonal, the radionuclide uptake was determined using a thyroid specific scinllaon camera. For 27 cold nodules 99m Tc-MIBI was used for evaluaon; 13 indifferent nodules were measured with 99m Tc-pertechnetate. Results: The relave change of uptake was detected as a quoent of pre- and post- therapeuc uptake. The stascal analysis of scingraphy data proved the e fficacy of microwave ablaon. 99m Tc-pertechnetate scingraphy showed an uptake reducon of 39% (range 9 to 85%). 99m Tc-MIBI imaging showed a median reducon of 40% (p

The results of the study on natural radionuclide content in 102 samples of the moss species randomly collected in 2008- 2013 at 30 locations of eastern Serbia are presented in the paper. The activity concentration values of 238U, 226Ra, 232Th, 40K, and 7Be determined by gamma spectrometry were within the intervals: 238U (1.1−50) Bq kg-1, 226Ra (1.1−41) Bq kg-1, 232Th (1.4−28) Bq kg-1, 40K (64−484) Bq kg-1 and 7Be (88−227) Bq kg-1, not standing out of the average data reported for this region. The distribution of the obtained data for 226Ra, 232Th, and 238U activity concentration in the analysed mosses has shown values up to 10 Bq kg-1 with frequencies 47.1 %, 54.9 % and 48.0 %, respectively. The obtained activity concentration values of primordial 40K and cosmogenic radionuclide 7Be were up to 500 Bq kg-1 and about 90 % of all the results for 7Be uptake by mosses were in the 200-250 Bq kg-1 concentration range.

Radionuclide uptake and contrast for positron emission tomography-computed tomography (PET-CT) images have been assessed in this study using NEMA image quality phantom filled with background activity concentration of 5.3 kBq/mL fluorodeoxyglucose (F-18 FDG). Spheres in the phantom were filled in turns with water to mimic cold lesions and FDG of higher activity concentrations to mimic tumor sites. Transaxial image slices were acquired on the PET-CT system and used for the evaluation of mean standard uptake value (SUV mean ) and contrasts for varying sphere sizes at different activity concentrations of 10.6 kBq/mL, 21.2 kBq/mL, and 42.4 kBq/mL. For spheres of same sizes, SUV mean increased with increase in activity concentration. SUV mean was increased by 80.6%, 83.5%, 63.2%, 87.4%, and 63.2% when activity concentrations of spheres with a diameter of 1.3 cm, 1.7 cm, 2.2 cm, 2.8 cm, and 3.7 cm, respectively, were increased from 10.6 kBq/mL to 42.4 kBq/mL. Average percentage contrast between cold spheres (cold lesions) and background activity concentration was estimated to be 89.96% for the spheres. Average contrast for the spheres containing 10.6 kBq/mL, 21.2 kBq/mL, and 42.4 kBq/mL were found to be 110.92%, 134.48%, and 150.52%, respectively. The average background contrast variability was estimated to be 2.97% at 95% confidence interval (P < 0.05).

Purpose: Hypoxic regions of tumors are less sensitive to radio- and chemotherapy, leading to poor prognosis of patients. One option to overcome the radioresistance is the irradiation of hypoxic tumors with high linear energy transfer (LET) α- or Auger electronemitters assuming their radiotoxicity would be less dependent on the cellular oxygenation status. Therefore, the aim of the present study was to determine whether irradiation with the intracellularly distributed Auger electron/γ-emitter 99mTc using the tracer [99mTc]TcHMPAO is a promising therapeutic option for the treatment of hypoxic tumor cells. Thus, the high LET α-particleemitter 223Ra ([223Ra]RaCl2) and the low LET β-emitter 188Re ([188Re]NaReO4) were studied in comparison to [99mTc]Tc-HMPAO. Materials and methods: A431 tumor cells were incubated with [99mTc]Tc-HMPAO (1–20 MBq/2 mL), [223Ra]RaCl2 (1.4–16.3 kBq/2 mL) or [188Re]NaReO4 (0.3–13.7 MBq/2 mL) under normoxic or hypoxic conditions. The degree of radiotoxicity was analyzed using the colony forming assay (CFA), and the intracellular radionuclide uptake of the radiotracers was quantified. Results: Hypoxic A431 cells are less radiosensitive to irradiation with [99mTc]Tc-HMPAO or [188Re]NaReO4 than normoxic ones. In contrast, the radiosensitivity of A431 cells is almost independent of the oxygen status when treated with the [223Ra]RaCl2. Conclusions: We demonstrate that the Auger electron/γ-emitter 99mTc ([99mTc]Tc-HMPAO), which does not bound directly to the DNA, is not a promising therapeutic option for hypoxic tumor cells. But the high LET α-particle-emitter 223Ra is more suitable for the treatment of hypoxic tumor cells than irradiation with [99mTc]Tc-HMPAO or the low LET bemitter 188Re. Zielsetzung: Hypoxische Tumorregionen sind bei Radio- und Chemotherapie weniger sensitiv als Tumorregionen mit ausreichender Sauerstoffversorgung. Dies verursacht eine schlechte Prognose fur Tumorpatienten. Eine Option die Radioresistenz zu uberwinden, stellt die Bestrahlung mit α-Partikel-Emittern oder Auger-Elektronen-Emittern mit einem hohen linearen Energietransfer (LET) dar. In dieser Studie soll untersucht werden, ob die Bestrahlung von hypoxischen Tumorzellen mit dem intrazellular aufgenommenen γ- sowie Auger-Elektronen-Emitter 99mTc unter Verwendung des Radiotracers [99mTc]Tc-HMPAO eine vielversprechende Therapieoption darstellen konnte. Vergleichend wurde der Hoch-LET α-Partikel-Emitter 223Ra ([223Ra]RaCl2) und der Niedrig-LET β-Emitter 188Re ([188Re]NaReO4) eingesetzt. Methoden: A431 Tumorzellen wurden unter normoxischen oder hypoxischen Kulturbedingungen mit [99mTc]Tc-HMPAO (1–20 MBq/2 ml), [223Ra]RaCl2 (1,4–16,3 kBq/2 ml) und [188Re]NaReO4 (0,3–13,7 MBq/2 ml) inkubiert. Zur Detektion der resultierenden strahlenbiologischen Wirkung wurde der Koloniebildungsassay angewendet. Zusatzlich wurde die intrazellulare Aufnahme der Radiotracer quantifiziert. Ergebnisse: Nach Inkubation von [99mTc]Tc-HMPAO sind hypoxische A431-Zellen weniger strahlensensitiv als normoxische Zellen. Im Gegensatz zur Behandlung mit [99mTc]Tc-HMPAO oder [188Re]NaReO4 wurde bei Behandlung mit [223Ra]RaCl2 ein geringerer Einfluss des Sauerstoffstatus auf die Radiosensitivitat von A431-Zellen gefunden. Schlussfolgerung: Damit konnte gezeigt werden, dass der nicht direkt an die DNA gebundene Auger-Elektronen-/ γ-Emitter 99mTc ([99mTc]Tc-HMPAO) die Radioresistenz von hypoxischen Tumorzellen nicht uberwinden kann. Jedoch stellt der Hoch-LET α-Partikel-Emitter 223Ra ([223Ra]RaCl2) eine bessere Behandlungsoption dar.

The purpose of the study is to quantify the level of uptake of administered radionuclide in primary bone tumors for patients undergoing bone scintigraphy. Retrospective study on 48 patient's scintigrams to quantify the uptake levels of administered radiopharmaceuticals was performed in a nuclear medicine unit in Ghana. Patients were administered with activity ranging between 0.555 and 1.110 MBq (15–30 mCi), and scanned on Siemens e.cam SPECT system. Analyses on scintigrams were performed with Image J software by drawing regions of interest (ROIs) over identified hot spots (pathologic sites). Nine skeletal parts namely cranium, neck, shoulder, sacrum, sternum, vertebra, femur, ribcage, and knee were considered in the study, which involved 96 identified primary tumors. Radionuclide uptakes were quantified in terms of the estimated counts of activity per patient for identified tumor sites. Average normalized counts of activity (nGMC) per patient ranged from 5.2759 ± 0.6590 cts/mm2/MBq in the case of cranium tumors to 72.7569 ± 17.8786 cts/mm2/MBq in the case of ribcage tumors. The differences in uptake levels could be attributed to different mechanisms of Tc-99m MDP uptake in different types of bones, which is directly related to blood flow and degree of osteoblastic activity. The overall normalized count of activity for the 96 identified tumors was estimated to be 23.0350 ± 19.5424 cts/mm2/MBq. The study revealed highest uptake of activity in ribcage and least uptake in cranium. Quantification of radionuclide uptakes in tumors is important and recommended in assessing patient's response to therapy, doses to critical organs and in diagnosing tumors.

// Sarah Urnauer 1 , Andrea M. Muller 1 , Christina Schug 1 , Kathrin A. Schmohl 1 , Mariella Tutter 1 , Nathalie Schwenk 1 , Wolfgang Rodl 2 , Stephan Morys 2 , Michael Ingrisch 3 , Jens Bertram 4 , Peter Bartenstein 5 , Dirk-Andre Clevert 3 , Ernst Wagner 2 and Christine Spitzweg 1 1 Department of Internal Medicine IV, University Hospital of Munich, LMU Munich, Munich, Germany 2 Department of Pharmacy, Center of Drug Research, Pharmaceutical Biotechnology, LMU Munich, Munich, Germany 3 Department of Clinical Radiology, University Hospital of Munich, LMU Munich, Munich, Germany 4 Department of Nuclear Medicine, Radiopharmacy, Klinikum rechts der Isar der Technischen Universitat Munchen, Munich, Germany 5 Department of Nuclear Medicine, University Hospital of Munich, LMU Munich, Munich, Germany Correspondence to: Christine Spitzweg, email: Christine.Spitzweg@med.uni-muenchen.de Keywords: sodium iodide symporter, gene therapy, theranostic application, nonviral EGFR-targeted gene transfer, colon cancer metastases Received: April 26, 2017 Accepted: August 04, 2017 Published: September 16, 2017 ABSTRACT Liver metastases present a serious problem in the therapy of advanced colorectal cancer (CRC), as more than 20% of patients have distant metastases at the time of diagnosis with less than 5% being cured. Consequently, new therapeutic approaches are of major need together with high-resolution imaging methods that allow highly specific detection of small metastases. The unique combination of reporter and therapy gene function of the sodium iodide symporter (NIS) may represent a promising theranostic strategy for CRC liver metastases allowing non-invasive imaging of functional NIS expression and therapeutic application of 131 I. For targeted NIS gene transfer polymers containing linear polyethylenimine (LPEI), polyethylene glycol (PEG) and the epidermal growth factor receptor (EGFR)-specific ligand GE11 were complexed with human NIS DNA (LPEI-PEG-GE11/NIS). Tumor specificity and transduction efficiency were examined in high EGFR-expressing LS174T metastases by non-invasive imaging using 18 F-tetrafluoroborate ( 18 F-TFB) as novel NIS PET tracer. Mice that were injected with LPEI-PEG-GE11/NIS 48 h before 18 F-TFB application showed high tumoral levels (4.8±0.6% of injected dose) of NIS-mediated radionuclide uptake in comparison to low levels detected in mice that received untargeted control polyplexes. Three cycles of intravenous injection of EGFR-targeted NIS polyplexes followed by therapeutic application of 55.5 MBq 131 I resulted in marked delay in metastases spread, which was associated with improved animal survival. In conclusion, these preclinical data confirm the enormous potential of EGFR-targeted synthetic polymers for systemic NIS gene delivery in an advanced multifocal CRC liver metastases model and open the exciting prospect of NIS-mediated radionuclide therapy in metastatic disease.

This study is based on evaluation of solidification methods for low-level radioactive liquid using natural zeolite. In classical method, LLW is decontaminated using zeolite and after the process spent zeolite becomes radioactive waste. After decontamination process, zeolite waste is solidified using cement, sand and water. In this method; liquid radioactive waste was used instead of water, natural zeolite was used instead of sand/aggregate and cement was used for binding the mixture in solidification process. In this study, leaching properties and strength of the solidified waste form were investigated for both techniques. Effect of temperature on the radionuclide adsorption of the zeolite was determined to optimize the waste solution temperature for the plant scale operations. In addition, the effect of pH on the radionuclide uptake of the zeolite was determined to optimize the waste solution’s pH for the plant scale operations. The advantages of this method used for the processing of LLW were discussed in this paper.

Study on 95 patients to compare radionuclide uptake levels in patients undergoing bone scintigraphy at a Nuclear Medicine Unit has been performed quantitatively using Image J software. Patients were administered with activity ranging from 0.555 to 1.110 MBq depending on their body weight, and their whole-body bone scans obtained with an installed e.cam single-photon emission computed tomography system. Matrix size of 256 × 1024 was used in acquiring the scintigrams. Quantitative analyses performed with installed Image J software revealed higher radionuclide uptake levels in metastatic tumors compared with primary tumors for all selected skeletal parts. Average normalized count of activity in metastatic tumors was 37.117 ± 27.740 cts/mm 2 /MBq and its corresponding uptake in primary tumors was 23.035 ± 19.542 cts/mm 2 /MBq. The relative higher uptake in metastatic tumors over primary tumors could be attributed to higher osteoblastic activity and blood flow in metastatic tumors.

Mandibular condylar hyperplasia (CH) is a complex developmental deformity resulting in asymmetries of the hyperplastic condyle. Bone scan SPECT is a sensitive and accurate method of detecting the growth activity of this disorder. This method can be used to quantitate the radionuclide uptake differences between the left and right condyles. Uptake differences of 10% or more between the left and right condyles, with increased uptake ipsilateral to the CH, are considered to be evidence of active growing CH. Quantitative assessment of CH is important to select an appropriate treatment course. Degenerative arthropathies of the temporomandibular joints may result in altered uptake, but this is mostly associated with the side contralateral to the CH. The CT portion of SPECT/CT is useful to assess the condylar dimensions and underlying bony changes.

Objective: To find out the value of correlating radiographic and scintigraphic imaging for defining the extent and nature of benign jaw lesions (BJL). Material and Methods: Twenty patients with histologically proven benign lesions of the jaws were investigated pre-operatively by panoramic radiography (PR) and bone scintigraphy (BS). To test the efficacy of combination of these two imaging modalities, their results were compared with intra-operative and histopathological findings. Result: Most of the benign lesions presented radiographically as well-defined bone destructions with fine sclerotic rims. Such lesions were found to be silent on scintigraphs and the extent of radionuclide uptake was same as radiographically visible extent of bone involvement. However, aggressive lesions showed ill-defined bone destructions without sclerotic rims on radiographs and their scintigraphic uptake correctly exceeded the radiographic extent of the bone involvement. Conclusion: The efficacy of combination of both complementary imagings is rewarding in defining the extent of the BJL, especially when radiographic margins are not so well defined. So, that surgical excisions will be complete and the possibility recurrences is reduced.

Modern nuclear medicine frequently needs to be supported by software for calculations. A self-designed free-accessible online tool named “Calculator” is presented. It can be used from the web-site www.nuk.bieganski.org, option “Calculator”. The programs offer: calculations of quantity of a radionuclide after a time (equation of simple radioactive decay), quantity of the second and third nuclide in the decay chain (successive radioactive decay, computation with Bateman equations and their limits), converting of activity units as well as of activity of a radioactive substance into its mass and vice versa, and calculations related to radionuclide therapy (radionuclide uptake, effective half time and activity needed for therapy). Mathematical and historical backgrounds of the algorithms used are shortly discussed in this work.

Summary This retrospective study summarises the case details, presenting signs, management and outcome in cases of temporohyoid osteoarthropathy (THO) and describes the findings of diagnostic imaging modalities. The condition appears to be relatively rare in Europe and the objective of this study is to make clinicians aware that THO can have a range of various neurological and clinical presentations. The records of 2 referral equine practices in England were reviewed and 7 horses with THO diagnosed on guttural pouch endoscopy indentified. The clinical and neurological signs, diagnostic procedures, treatment and outcomes were reviewed. Although small, this group is the largest case series of THO from Europe. One horse was a yearling, whereas THO is generally considered usually to affect middle aged and older horses. Computed tomography was used to confirm the diagnosis and demonstrated stylohyoid bone fractures in 2 cases while there was mild increased radionuclide uptake in one of 2 cases undergoing nuclear scintigraphy. Treatment is still controversial, although ceratohyoidectomy led to complete resolution of signs in 2 of 5 cases thus treated and improvement in the other 3. One horse with mild signs treated with antimicrobials and nonsteroidal anti-inflammatory drugs made a full recovery while another, presented with head shaking and managed with a phased exercise programme, improved but did not resolve completely.

Congenital hypothyroidism, occurring in 1:3000 newborns, is one of the most common preventable causes of mental retardation. Neurodevelopmental outcome is inversely related to the age of diagnosis and treatment. Infants detected through newborn screening programs and started on l-T4 in the first few weeks of life have a normal or near-normal neurodevelopmental outcome. The recommended starting dose of l-T4 (10–15 μg/kg · d) is higher on a weight basis than the dose for children and adults. Tailoring the starting l-T4 dose to the severity of the hypothyroidism will normalize serum T4 and TSH as rapidly as possible. It is important to obtain confirmatory serum thyroid function tests before treatment is started. Further diagnostic studies, such as radionuclide uptake and scan and ultrasonography, may be performed to determine the underlying cause of hypothyroidism. Because results from these tests generally do not alter the initial treatment decision, however, these diagnostic studies are rarely indicated. The developing brain has a critical dependence on thyroid hormone for the first 2–3 yr of life; thus, monitoring occurs at more frequent intervals than in older children and adults. Serum free T4 and TSH should be checked at intervals frequent enough to ensure timely adjustment of l-T4 dosing and to keep serum free T4 and TSH levels in target ranges. Given the success of early detection and treatment of neonates with congenital hypothyroidism, a public health mandate should be to develop similar programs for the 75% of babies worldwide who are born in areas without newborn screening programs.

The purpose of the study was to investigate natural radionuclide uptake and allocation by trees.Samples from six Scots pines (P. sylvestris), six Norway spruces (Picea abies) and one sycamore maple (Acer pseudoplatanus) tree, growing on the Boršt uranium mill tailings waste pile in Slovenia were collected. (238)U, (230)Th, (226)Ra and (210)Pb activity concentrations in wood, shoots and 1-year-old needles or leaves were determined. Particular radionuclides were separated from the samples by appropriate radiochemical procedures and their activity concentrations measured with an alpha spectrometry system. In addition, concentration ratios for different plant parts were calculated.Results showed that for all radionuclides, the highest activity concentrations were found in foliage, followed by shoots and wood. The activity concentrations in trees were from 0.01 to 5.4 Bq kg(-1) for (238)U, 0.03-11.3 Bq kg(-1) for (230)Th, 2.7-2,728 Bq kg(-1) for (226)Ra and 5.1-321 Bq kg(-1) for (210)Pb. All activity concentrations were calculated on dry weight basis. The calculated concentration ratios were from 1.05E-5 to 5.39E-3 for (238)U, 7.65E-6-2.88E-3 for (230)Th, 3.10E-4-3.16E-1 for (226)Ra and 6.70E-4-4.22E-2 for (210)Pb.

Radionuclide bone scanning was proven effective many years ago. Its main advantages are good sensitivity, limited radiation exposure, and noninvasiveness. However, increased radionuclide uptake by a lesion is not specific, and differentiating malignant from nonmalignant disorders may therefore be difficult. An additional structural imaging study is often needed to establish the final diagnosis. Furthermore, the limited resolution of radionuclide bone scanning images does not allow accurate localization of the lesions. Single-photon emission computed tomography (SPECT) combined with computed tomography (CT) provides both structural and functional information. SPECT/CT has been proven useful for interpreting radionuclide bone scan results in patients with bone malignancies, showing far better specificity than planar imaging or SPECT alone, most notably in the evaluation of spinal abnormalities. SPECT/CT provides an accurate evaluation of the site of the lesions and also supplies other information that can be useful in nonmalignant conditions such as injuries, infections, and degenerative disease. Nevertheless, there are only a few published studies on the usefulness of SPECT/CT in nonmalignant conditions. However, SPECT/CT is only starting to become available and may become a routine investigation for a number of rheumatic disorders.

This work is based on the describing a new approach in estimation of Concentration Factor (CF) for marine organisms radionuclides uptake. We considered the dependence of CF from the water salinity (determining the K + and Ca 2+ ions). The radionuclide uptake by the marine biota of Dnieper-Bug Estuary using the numerical compartment-model POSEIDON-R with latest modifications was applied. The levels of radionuclides in the different marine organisms, representing the various types of marine organisms in the different trophic levels of the foodweb, were calculated. The uptake model takes into account both the uptake of radionuclides via food consumption, by describing the predator-prey relations, and the direct uptake of radionuclides from the water via the gills. The influence of the K + and Ca 2+ ions, competitive ions against 137 Cs + , 90 Sr 2+ ions respectively, on the uptake rate was investigated.

Scaling factors, used to predict radionuclide uptake as a function of mass, have tremendous potential to provide a more transparent approach to risk assessment. Although the historical literature might seem to offer a wealth of data for the purposes of testing these scaling relationships, a more defensible alternative may be to conduct new site-specific data collection efforts. Trace element analysis was conducted on 16 plant species from a single location in Oregon. Results for ten elements and six species exhibit mass dependence on trace-element uptake. Transfer factors calculated for several elements spanned only an order of magnitude across all plant species. Conversely, radionuclide data taken from the open literature was inconclusive in the analysis for mass effects.

As revealed by previous theoretical studies, targeted radionuclide therapy (TRT) that relies on a single beta-emitting radioisotope is likely to be inappropriate for clinical scenarios such as disseminated malignancy. For a patient with a vast number of tumours and metastases of largely differing sizes a high level of therapeutical efficiency might be achieved only for a restricted range of tumour sizes. This is due to the limited range of beta-electrons in human tissue, essentially causing the therapeutical impact to vary tremendously with tumour size. The dependence of curability on the tumour dimension is expected to be significantly altered if a radionuclide cocktail, consisting of a long-range and a short-range beta-emitter, such as (32)P and (33)P, is involved in the treatment. In this study, a radiation transport simulation was performed, using the MCNP4c2 Monte Carlo code, in order to investigate the relationship between tumour control probability (TCP) and tumour size, associated with concurrent use of (32)P and (33)P. Two different models of intratumoural distribution of cumulated activity were taken into account. One simulated an ideal radionuclide uptake in tumour tissue and the other referred to a limited radiotracer penetration. The results were examined in comparison to tumours targeted with pure (32)P, (33)P and (131)I. For both uptake scenarios a considerable reduction of the overall variation of TCP and thus an increasing chance of achieving tumour cure was observed for tumour sizes ranging from microscopic dimensions up to macroscopic diameters, if the targeted radionuclide treatment relies on a (32)P/(33)P cocktail. It was revealed that particular attention has to be given to the ratio of the (32)P and (33)P specific cumulated activities (SCA) in the tumour, since this is a significant determinant of the resulting behaviour of tumour control probability as the tumour diameter varies. This study suggests that a 32P/33P approach is more applicable to diseases that involve a variety of tumours and metastases differing in size.

Positron emission tomography (PET) with fluorine 18 fluorodeoxyglucose (FDG) is used to diagnose, stage, and monitor breast cancer. FDG PET has the capability to depict abnormal metabolic activity before any anatomic change occurs; however, in the absence of identifiable anatomic structures on PET images, it may be impossible to identify the location of areas of increased radionuclide uptake. In such cases, the coregistration of PET images with images from computed tomography (CT) may help improve diagnostic accuracy and lead to better clinical management of patients with breast cancer. Although FDG PET/CT may have limited diagnostic value for detecting small primary breast tumors, well-differentiated breast cancer, or regional lymph node involvement, it is superior to conventional imaging modalities for detecting distant metastases and recurrences and for monitoring the response to therapy.

We report an inter-comparison of eight models designed to predict the radiological exposure of radionuclides in marine biota. The models were required to simulate dynamically the uptake and turnover of radionuclides by marine organisms. Model predictions of radionuclide uptake and turnover using kinetic calculations based on biological half-life (T-B1/2) and/or more complex metabolic modelling approaches were used to predict activity concentrations and, consequently, dose rates of Sr-90, I-131 and Cs-137 to fish, crustaceans, macroalgae and molluscs under circumstances where the water concentrations are changing with time. For comparison, the ERICA Tool, a model commonly used in environmental assessment, and which uses equilibrium concentration ratios, was also used. As input to the models we used hydrodynamic forecasts of water and sediment activity concentrations using a simulated scenario reflecting the Fukushima accident releases. Although model variability is important, the intercomparison gives logical results, in that the dynamic models predict consistently a pattern of delayed rise of activity concentration in biota and slow decline instead of the instantaneous equilibrium with the activity concentration in seawater predicted by the ERICA Tool. The differences between ERICA and the dynamic models increase the shorter the T-B1/2 becomes; however, there is significant variability between models, underpinned by parameter and methodological differences between them. The need to validate the dynamic models used in this intercomparison has been highlighted, particularly in regards to optimisation of the model biokinetic parameters. (C) 2015 Elsevier Ltd. All rights reserved.

Objective To evaluate different magnetic resonance (MR) imaging sequences in integrated positron emission tomography (PET)/MR concerning their ability to detect tumors and allocate increased radionuclide uptake on 18 F-fluorodeoxyglucose ( 18 F-FDG) PET in intraindividual comparison with computed tomography (CT) from PET/CT. Material and methods Sixty-one patients (34 female, 27 male, mean age 57.6y) who were examined with contrast-enhanced PET/CT and subsequent PET/MR (mean delay for PET/MR after injection: 147±43min) were included. A maximum of ten 18 F-FDG-avid lesions per patient were analyzed on CT from PET/CT and with the following MR sequences from PET/MR: T2, turbo inversion recovery magnitude (TIRM), non-enhanced T1, contrast-enhanced T1, and diffusion-weighted imaging (DWI). All lesions were rated using a four-point ordinal scale (scored from 0 to 3) concerning visual detectability of the lesion against the surrounding background and anatomical allocation of the PET finding. In each category (detectability and allocation), Wilcoxon rank sum tests were performed. Bonferroni–Holm correction was performed to prevent α-error accumulation. Results In 225 18 F-FDG-avid lesions (156 confirmed as malignant by radiological follow up, 69 by histopathology), visual detectability was comparably high on CT (mean: 2.5±0.9), TIRM (mean: 2.5±0.9), T2 (mean: 2.4±0.9), and DWI (mean: 2.5±1.0) and was significantly higher than on non-enhanced T1 (mean: 2.2±1.0). While anatomic allocation of the PET finding was comparable with CT (mean: 2.6±0.7), T2 (mean: 2.6±0.7), and TIRM (mean: 2.8±0.7), it was significantly higher compared to DWI (mean: 2.1±1.0) and non-enhanced T1 (mean: 2.4±0.8). Conclusion In conclusion, T2, TIRM, and contrast-enhanced T1 provide a high quality of lesion detectability and anatomical allocation of FDG-avid foci. Their performance is at least comparable to contrast-enhanced PET/CT. Non-enhanced T1 may be omitted and the necessity of DWI should be further investigated for specific questions, such as assessment of the liver.