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The purpose of this study was to quantify the metabolic equivalents (METs) of resistance exercise in obese patients with type 2 diabetes (T2DM) and healthy young subjects and to evaluate whether there were differences between sessions executed at low- versus high-intensity resistance exercise. Twenty obese patients with T2DM (62.9±6.1 years) and 22 young subjects (22.6±1.9 years) performed two training sessions: one at vigorous intensity (80% of 1-repetition maximum (1RM)) and one at moderate intensity (60% of 1RM). Both groups carried out three strength exercises with a 2-day recovery between sessions. Oxygen consumption was continuously measured 15 min before, during and after each training session. Obese T2DM patients showed lower METs values compared with young healthy participants at the baseline phase (F= 2043.86; P<0.01), during training (F=1140.59; P<0.01) and in the post-exercise phase (F=1012.71; P<0.01). No effects were detected in the group x intensity analysis of covariance. In this study, at both light-moderate and vigorous resistance exercise intensities, the METs value that best represented both sessions was 3 METs for the obese elderly T2DM patients and 5 METs for young subjects. [ABSTRACT FROM AUTHOR]

The purpose of this study was to quantify the metabolic equivalents (METs) of resistance exercise in obese patients with type 2 diabetes (T2DM) and healthy young subjects and to evaluate whether there were differences between sessions executed at low- versus high-intensity resistance exercise. Twenty obese patients with T2DM (62.9±6.1 years) and 22 young subjects (22.6±1.9 years) performed two training sessions: one at vigorous intensity (80% of 1-repetition maximum (1RM)) and one at moderate intensity (60% of 1RM). Both groups carried out three strength exercises with a 2-day recovery between sessions. Oxygen consumption was continuously measured 15 min before, during and after each training session. Obese T2DM patients showed lower METs values compared with young healthy participants at the baseline phase (F= 2043.86; P<0.01), during training (F=1140.59; P<0.01) and in the post-exercise phase (F=1012.71; P<0.01). No effects were detected in the group x intensity analysis of covariance. In this study, at both light-moderate and vigorous resistance exercise intensities, the METs value that best represented both sessions was 3 METs for the obese elderly T2DM patients and 5 METs for young subjects. [ABSTRACT FROM AUTHOR]

Abstract: Background and aims: Apart from late motor nerve dysfunction, factors affecting muscle strength in diabetes are largely unknown. This study was aimed at assessing muscle strength correlates in diabetic subjects encompassing a wide range of peripheral nerve function and various degrees of micro and macrovascular complications. Methods and results: Four-hundred consecutive patients with type 1 and 2 diabetes (aged 46.4 ± 13.9 and 65.8 ± 10.3 years, respectively) from the Study on the Assessment of Determinants of Muscle and Bone Strength Abnormalities in Diabetes (SAMBA) were examined for upper and lower body muscle isometric maximal voluntary contraction by dynamometry. Univariate and multivariate regression analyses were applied to identify strength correlates. Isometric force at both the upper and lower limbs was significantly lower in subjects with than in those without any complication. At univariate analysis, it was strongly associated with age, diabetes duration, physical activity (PA) level, cardio-respiratory fitness, anthropometric parameters, surrogate measures of complications, and parameters of sensory and autonomic, but not motor (except amplitude) neuropathy. Multivariate analysis revealed that upper and lower body strength correlated independently with male gender and, inversely, with age, autonomic neuropathy score (or individual autonomic function abnormalities), and vibration perception threshold, but not sensory-motor neuropathy score. Diabetes duration and PA level were excluded from the model. Conclusions: Both upper and lower body muscle strength correlate with measures of diabetic complications and particularly with parameters of sensory and especially autonomic nerve function, independently of diabetes duration and PA level, thus suggesting the involvement of mechanisms other than manifest motor nerve impairment. Trial Registration number and date: NCT01600924; 05.06.2012. [Copyright &y& Elsevier]

Purpose Statistical process control (SPC) is a tool widely used in industrial engineering to monitor and improve processes, allowing early detection and prevention of problems. We retrospectively applied SPC methods on daily Tomotherapy output check in order to assess the possibility to use it as predictive maintenance tool. Methods and materials From January 2014 to September 2017 a total of 1916 daily output check have been performed in static (958) and dynamic (958) modality, using the "cheese" phantom and a ionization chamber inserted into it. In the first case, a static field of 5 cm × 40 cm has been used, while an optimized IMRT plan was considered in the second case. All collected data have been organized per year, and for each year in subgroup of 30 data, representing approximately a month of output checks. Individual (I) and exponentially weighted moving average (EWMA) charts have been used to monitoring the long and short term data variability, respectively. The process performance was evaluated by means of capability indices using the Chan method. Results For each year considered in the study, the I- and EWMA-charts have shown the presence of out of control situation referable to specialist interventions. In particular, as reported in the figure below, the EWMA-charts have shown the presence of out of control situations before the interventions. Even if the tolerance suggested by AAPM TG 148 have been respected in the considered period of time, the process performance were in agreement with the scenario considered: the higher the interventions, the worst the results. Conclusion SPC methods are able to effectively detect variation in Tomotherapy output checks. Further investigation will consider on-line daily results. [ABSTRACT FROM AUTHOR]

Purpose Radiometabolic treatment with 177Lu-PSMA (prostate-specific membrane-antigen) have shown to be a promising option for progressive prostate cancer patients with metastatic disease. Main organ toxicity limiting maximum injectable activity were kidneys(KDs), parotid glands(PGs) and red marrow(RM). We evaluated the delivered dose to healthy tissues(KDs, PGs, RM) for177Lu-PSMA treatments in combination with mannitol intra-venous infusion and iron mineral glutamate oral administration(via candy) combined with ice external application in order to reduce KDs and PGs uptake, respectively. Methods and materials Six patients were enrolled (Table 1). Post injection whole body(WB) planar scans and blood samples were acquired at different timing (1 h, 16–24 h, 36–48 h, 120 h post-injection). ROIs for whole body, KDs and PGs were contoured on the first image and transferred to all others(Xeleris software,GE). KDs and PGs mean counts were normalized to initial whole body activity and (corrected for background, scatter, physical decay and patient's thickness) used to generate biological time-activity curves. Blood samples measurements (High-Purity Germanium detector) were used for RM uptake activity and biological time-activity curve estimation. Dose calculations in terms of mGy/MBq were performed following MIRD formalism(OLINDA/EXM software). Obtained results were compared to previous studies [1,2] with unpaired T-test. Results No statistically significant difference was found for whole body (median[range]:0.04[0.02–0.05] vs 0.05[0.01–0.10] mGy/MBq, p-value = 0.37) or RM (0.04[0.001–0.08] vs 0.03[0.01–0.06], p-value = 0.85) absorbed dose (Figure1). Absorbed dose to kidneys was lower for our patient cohort (0.20[0.11–0.31]) compared to data[1,2](0.86[0.20–1.90]), with statistically significance (p-value = 0.001). Parotid glands absorbed dose was not statistically significant different considering all patients(0.79[0.33–1.24] vs 1.73[0.30–9.50], p-value = 0.24), but the difference increased considering only patients that received iron mineral candy administration (0.40[.33–0.47] vs 1.73[0.30–9.50], p-value = 0.09). Conclusions The possibility to reduce kidneys and parotid gland absorbed dose in 177Lu-PMSA treatments with the administration of combined therapies was shown. The increased of therapeutic index (i.e. same injected activity vs lower dose to main limiting healthy tissues) may provide the possibility to perform injected activity escalation of 177Lu-radioisotope linked to PSMA, compared to previous ligand. [ABSTRACT FROM AUTHOR]

Purpose Air monitoring systems are mandatory in all areas potentially contaminated with airborne radioactivity, such as hot laboratories, treatment rooms, and radioactive waste storage areas. The calibration of such systems may be practically complicated or require the application of correction factors, obtained by means of approximated analytical calculations. Monte Carlo techniques provide an effective way to check the calibration and the impact of the approximations used in the calculation. Methods The present work compares two different systems: a continuous air monitoring system, composed by a NaI detector located inside a chimney, and an air pumping system that measures the sample activity in a Marinelli beaker geometry, equipped with NaI detector. This setup allows to calibrate the continuous air monitoring system using the measurements provided by the Marinelli beaker system. A self-absorption correction factor, applied in the calibration of the Marinelli beaker system, is derived for gamma and beta+ radiation and compared with approximated analytical calculation available for gamma [1]. The cross-calibration of the two systems is complicated by the presence of F18 that sticks to the duct's walls, producing a background that continuously increases during the air flow, therefore the calibration constants are checked using an approximate analytical calculation and a Geant4 simulation. Results Calibration factors are computed for ducts of different sizes and lengths, and validated using the IRST monitoring system. These coefficients represent a useful estimate in the calibration of continuous air monitoring systems in all cases where the cross-calibration of two systems is not possible. Conclusions Monte Carlo techniques help in overcome challenging aspects in the calibration of air monitoring systems, providing reliable results that can be used to cross-check the calibration constants of the system in case of large experimental uncertainties. [ABSTRACT FROM AUTHOR]

Purpose To present our results regarding the commissioning of the RayStation TPS and to compare its dosimetric accuracy with the clinical Pinnacle TPS. Methods A 6 MV beam quality of an Elekta Synergy was considered for modeling in RayStation. The dose calculation accuracy was tested in several situations. Firstly, measured PDD and profiles were compared with calculations using the 1D-gamma analysis. Secondly, using the test fields from the ESTRO booklet No. 7, absolute point doses were measured in a water phantom and compared with calculated values. Then, IMRT and VMAT techniques were tested performing pre-treatment verifications with the PTW-Octavius4D system. For this purpose, the AAPM TG-119 test cases as well as 20 clinical patients with various treatment sites were considered. The agreement between measurements and calculations was assessed with 3D-gamma analysis. Finally, 10 VMAT clinical cases optimized with Pinnacle were recalculated in RayStation. Dose distributions from both TPSs were compared with measurements. Results maximum values of 1D-gamma confidence-level were 0.6 for PDDs (2%-2 mm, local normalization, Table 1) and 0.75 for profiles (3%-2 mm, local normalization). Absolute point dose measurements agreed with calculated values within 1.5%. 3D-gamma pass-rates for the TG-119 cases and patient-specific verifications were within the ranges [97.2%-99.7%] and [89.0%-97.5%] for 3%-3 mm global and local normalization, espectively. Absolute differences between average gamma pass-rates of patient-specific verifications were 0.1% (3%-3 mm, global normalization) and 1.1% (3%-3 mm, local normalization). These differences were not statistically significant (minimum p-value for a Wilcoxon-signed-rank test was 0.51, Fig. 1). Conclusions RayStation was commissioned for a 6 MV beam quality of an Elekta Synergy. The dosimetric accuracy was tested in several situations, including standard international protocols. The agreement between measurements and calculations was clinically acceptable. Furthermore, RayStation accuracy was comparable with the clinically established Pinnacle TPS. [ABSTRACT FROM AUTHOR]

Focused ultrasound are recently introduced as alternative therapy for pain palliation caused by bone metastases. The heat absorption and propagation in the soft tissues and in the bones strongly depends on the correct focalization of the ultrasonic beam through the interfaces. The real-time thermal map provided by the MRI gives to the interventional radiologist the feedback for the online treatment planning. The present work is focused on the verification of planning therapy system of a MRgFUs system giving a verification of the propagation and the accumulation of the temperature in bones in particular for the pelvic bone. In this work it has been studied the Philips Sonalleve HIFU installed on Ingenia 3T. The thermal maps has been studied on a multi-interface phantom with albumin-agarose gel volumetric detector. The planned volume ablation temperature has been compared with the T2 imaging modification on the phantom. A dedicated software has been developed for the extraction of the thermal image maps from the system and for the evaluation of the cumulative thermal dose. A first approach has been proposed for the evaluation of the plan in term of DVH (dose/volume histogram). High impedance interfaces create local depositions of energy along the sonicated surfaces. The plan cumulative dose verification gives constraints to the physicians on sonication cells positioning. The MRgFUs feedback planning gives partial information of the heat deposition. The bone phantom is used to evaluate the real cells volume. The de-focalization created by bones demonstrate the needs of preplanning system dedicated to bones treatments. [ABSTRACT FROM AUTHOR]