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Purpose: This study investigated the use of high spatial resolution solid‐state detectors (DUO and Octa) combined with an inclinometer for machine‐based quality assurance (QA) of Volumetric Modulated Arc Therapy (VMAT) with flattened and flattening filter‐free beams. Method: The proposed system was inserted in the accessory tray of the gantry head of a Varian 21iX Clinac and a Truebeam linear accelerator. Mutual dependence of the dose rate (DR) and gantry speed (GS) was assessed using the standard Varian customer acceptance plan (CAP). The multi‐leaf collimator (MLC) leaf speed was evaluated under static gantry conditions in directions parallel and orthogonal to gravity as well as under dynamic gantry conditions. Measurements were compared to machine log files. Results: DR and GS as a function of gantry angle were reconstructed using the DUO/inclinometer and in agreement to within 1% with the machine log files in the sectors of constant DR and GS. The MLC leaf speeds agreed with the nominal speeds and those extracted from the machine log files to within 0.03 cm s−1. The effect of gravity on the leaf motion was only observed when the leaves traveled faster than the nominal maximum velocity stated by the vendor. Under dynamic gantry conditions, MLC leaf speeds ranging between 0.33 and 1.42 cm s−1 were evaluated. Comparing the average MLC leaf speeds with the machine log files found differences between 0.9% and 5.7%, with the largest discrepancy occurring under conditions of fastest leaf velocity, lowest DR and lowest detector signal. Conclusions: The investigation on the use of solid‐state detectors in combination with an inclinometer has demonstrated the capability to provide efficient and independent verification of DR, GS, and MLC leaf speed during dynamic VMAT delivery. Good agreement with machine log files suggests the detector/inclinometer system is a useful tool for machine‐specific VMAT QA. [ABSTRACT FROM AUTHOR]

Microdosimetry is a particularly powerful method to estimate the relative biological effectiveness (RBE) of any mixed radiation field. This is particularly convenient for therapeutic heavy ion therapy (HIT) beams, referring to ions larger than protons, where the RBE of the beam can vary significantly along the Bragg curve. Additionally, due to the sharp dose gradients at the end of the Bragg peak (BP), or spread out BP, to make accurate measurements and estimations of the biological properties of a beam a high spatial resolution is required, less than a millimetre. This requirement makes silicon microdosimetry particularly attractive due to the thicknesses of the sensitive volumes commonly being ∼10 m or less. Monte Carlo (MC) codes are widely used to study the complex mixed HIT radiation field as well as to model the response of novel microdosimeter detectors when irradiated with HIT beams. Therefore it is essential to validate MC codes against experimental measurements. This work compares measurements performed with a silicon microdosimeter in mono-energetic , and ion beams of therapeutic energies, against simulation results calculated with the Geant4 toolkit. Experimental and simulation results were compared in terms of microdosimetric spectra (dose lineal energy,), the dose mean lineal energy, y D and the RBE10, as estimated by the microdosimetric kinetic model (MKM). Overall Geant4 showed reasonable agreement with experimental measurements. Before the distal edge of the BP, simulation and experiment agreed within ∼10% for y D and ∼2% for RBE10. Downstream of the BP less agreement was observed between simulation and experiment, particularly for the and beams. Simulation results downstream of the BP had lower values of y D and RBE10 compared to the experiment due to a higher contribution from lighter fragments compared to heavier fragments. [ABSTRACT FROM AUTHOR]

Purpose Flattening filter free (FFF) beams are increasingly being considered for stereotactic radiotherapy (SRT). For the first time, the performance of a monolithic silicon array detector under 6 and 10 MV FFF beams was evaluated. The dosimeter, named “Octa” and designed by the Centre for Medical Radiation Physics (CMRP), was tested also under flattened beams for comparison. Methods Output factors (OFs), percentage depth-dose (PDD), dose profiles (DPs) and dose per pulse (DPP) dependence were investigated. Results were benchmarked against commercially available detectors for small field dosimetry. Results The dosimeter was shown to be a ‘correction-free’ silicon array detector for OFs and PDD measurements for all the beam qualities investigated. Measured OFs were accurate within 3% and PDD values within 2% compared against the benchmarks. Cross-plane, in-plane and diagonal DPs were measured simultaneously with high spatial resolution (0.3 mm) and real time read-out. A DPP dependence (24% at 0.021 mGy/pulse relative to 0.278 mGy/pulse) was found and could be easily corrected for in the case of machine specific quality assurance applications. Conclusions Results were consistent with those for monolithic silicon array detectors designed by the CMRP and previously characterized under flattened beams only, supporting the robustness of this technology for relative dosimetry for a wide range of beam qualities and dose per pulses. In contrast to its predecessors, the design of the Octa offers an exhaustive high-resolution 2D dose map characterization, making it a unique real-time radiation detector for small field dosimetry for field sizes up to 3 cm side. [ABSTRACT FROM AUTHOR]

X-ray fluorescence (XRF) analyses are affected by many matrix and geometrical factors that, generally, are possible to handle in laboratory conditions. However, when in situ analyses are considered, constraints in the measurement conditions make more difficult to handle some factors, such as moisture, affecting the measurement accuracy. Efforts have been made to correct some of the effects by inserting some steps in the sample preparation process. The problem is that each step added in this process, aiming a better precision and accuracy, makes the in situ measurement harder and longer to accomplish, influencing negatively the intrinsic advantages of the in situ measurement. In this work, we propose a method to correct the effect of soil moisture on in situ XRF analysis using low-energy background. The method demands a simple calibration, after which a long drying procedure is not necessary before measuring the samples. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objective: Gastrointestinal toxicity is the most important adverse effect of treatment with nonsteroidal anti-inflammatory drugs (NSAIDs). The present meta-analysis was undertaken to systematically review available data from randomised clinical trials on the tolerability of amtolmetin guacil (amtolmetin guacyl), a novel, effective NSAID. Design: Eighteen studies comparing the clinical efficacy and tolerability of amtolmetin guacil versus other NSAIDs were identified. The predefined end-points of the meta-analysis were the incidence of adverse effects at the gastrointestinal level (either requiring or not requiring drug withdrawal) and discontinuing treatment because of adverse effects, together with the occurrence of mild/severe lesions (or of severe lesions only), evaluated in three studies by the use of endoscopy. Results: In all the studies, the frequency of adverse events and early cessation of treatment was lower in patients treated with amtolmetin guacil than with other NSAIDs. The overall odds ratio of adverse effects for amtolmetin guacil versus all the other drugs considered together was 0.2 [95% confidence interval (CI) 0.1 to 0.3]. The frequency and severity of gastric mucosal lesions at endoscopic evaluation was lower for amtolmetin guacil in comparison with other NSAIDs: the typical odds ratio for severe lesions was 0.3 (95% CI 0.1 to 0.7), and for mild and severe lesions was 0.1 (95% CI 0.1 to 0.4). Conclusion: This meta-analysis indicated that the gastric tolerability of amtolmetin guacil was higher than that of established NSAIDs. The clinical implications of these findings should be prospectively tested in large long-term treatment trials. [ABSTRACT FROM AUTHOR]

Previous work on mice neonatally injected with Moloney-murine leukaemia virus (M-MuLV) had shown that T cell lymphoma development correlates with virus infection of lymphoreticular cells (T and B lymphocytes and macrophages) as well as with a lack of generation of virus-specific cytotoxic T lymphocytes (CTL) due to clonal deletion of CTL precursors. In the present report, viral antigen expression and T cell response in mice injected as adults with M-MuLV intrathymus (i.t.) was investigated. Only thymic and splenic T lymphocytes from these mice express virus-induced antigens since they were lysed by virus-specific CTL, and stained by anti-M-MuLV fluorescent serum. In addition, the percentage of M-MuLV-infected T cells increased with increasing post-inoculation times. However, these mice could mount a strong cellular immune response against M-MuLV-infected cells, as detected by massive mixed leucocyte tumour cell culture and by evaluation of virus-specific CTL precursor frequency. Finally, i.t. injected mice were not viraemic and did not develop lymphomas during an observation period of 12-15 months. These data, in contrast with the recent hypothesis that T cell lymphoma development depends on a chronic stimulation of virus-specific T lymphocytes, indicate that the cellular immune response is sufficient for prevention of neoplastic transformation, despite a persistent viral infection of the thymus and peripheral T lymphocytes. [ABSTRACT FROM AUTHOR]

Plasma lipids and lipoproteins, glucose, uric acid, and haemocoagulative parameters were studied in a group of 22 elderly hospitalized patients with arteriosclerotic dementia, and compared with those of a control group of a similar age. No significant differences were found in lipids, lipoproteins, glucose, or uric acid but the fibrinogen level was significantly raised in the group with arteriosclerotic dementia. A comparison of the metabolic parameters of the dementia patients with those of a group of subjects with peripheral occlusive arteriosclerosis showed, on the other hand, that this latter group had significantly raised plasma triglycerides as well as a significantly higher incidence of the Fredrickson phenotypes of hyperlipoproteinaemia. These findings indicate that the common laboratory parameters used to evaluate arteriosclerosis are not adequate to point out any pathogenic mechanism for arteriosclerotic dementia, and research should therefore be focused in other directions. [ABSTRACT FROM PUBLISHER]

This article presents information on a study that examined carotid stenting (CS) procedures performed by different specialists with different techniques. The article lists the variety of specialists involved in the study. Information is presented on the number of CS procedures performed. The technical success rate is discussed, as well as the ipsilateral stroke and neurologic death rate.

A sedimentary sequence that was highly sensitive to fault rupture-driven changes in water level and sediment supply has been used to extract a continuous record of 22 large earthquakes on the Alpine fault, the fastest-slipping fault in New Zealand. At Hokuri Creek, in South Westland, an 18 m thickness of Holocene sediments accumulated against the Alpine fault scarp from ca. A.D. 800 to 6000 B.C. We used geomorphological mapping, sedimentology, and paleoenvironmental reconstruction to investigate the relationship between these sediments and Alpine fault rupture. We found that repeated fault rupture is the most convincing mechanism for explaining all the features of the alternating peat and silt sedimentary sequence. Climate has contributed to sedimentation but is unlikely to be the driver of these cyclical changes in sediment type and paleoenvironment. Other nontectonic causes for the sedimentary alternations do not produce the incremental increase in basin accommodation space necessary to maintain the shallow-water environment for 6800 yr. Our detailed documentation of this near-fault sedimentary basin sequence highlights the advantages of extracting paleoearthquake records from such sites--the continuity of sedimentation, abundance of dateable material, and pristine preservation of older events. [ABSTRACT FROM AUTHOR]

Background: Geographic origin may represent a variable capable of influencing health status. This study aims to investigate the presence of differences of disease severity in Italian patients with fibromyalgia from different macro-regions., Methods: This retrospective, cross-sectional study involved patients included in the Italian Fibromyalgia Registry. Three geographical macro-regions were identified, comprising patients from Northern Italy, Central Italy and Southern Italy. Clinical differences (evaluated through PolySymptomatic Distress Scale [PSD], revised Fibromyalgia Impact Questionnaire [FIQR] and modified Fibromyalgia Assessment Status [FASmod]) among the geographical macro-regions were studied using one-way analysis of variance (ANOVA) and the Scheffé's test., Results: A total of 6095 patients (5719 females and 376 males) were included, with 1957 from Northern Italy, 2979 from Central Italy and 1159 from Southern Italy. All studied clinical indices showed a trend indicative of greater disease severity in Southern Italy, followed by Northern Italy and then Central Italy (mean values for PSD: 19.97 ± 6.20 in Northern Italy, 18.61 ± 7.12 in Central Italy, 23.01 ± 5.66 in Souther Italy). These differences were statistically significant for the overall scores of all studied indices, evaluated with ANOVA (all p < 0.001) and in the head to head comparisons, evaluted with Scheffé's test., Conclusions: Geographic background is significantly associated with variations in the severity of fibromyalgia in Italian patients., Significance Statement: This is the first study to demonstrate geographical origin-dependent intra-national differences in the severity of fibromyalgia. The results confirm the necessity of considering fibromyalgia within the context of the biopsychosocial model and of implementing healthcare policies targeted towards the most underserved regions., (© 2024 The Author(s). European Journal of Pain published by John Wiley & Sons Ltd on behalf of European Pain Federation ‐ EFIC ®.)

Introduction: Since the initial identification of Miller Fisher syndrome (MFS) and Bickerstaff brainstem encephalitis (BBE),significant milestones have been achieved in understanding these diseases.Discoveries of common serum antibodies (IgG anti-GQ1b), antecedent infections, neurophysiological data, andneuroimaging suggested a shared autoimmune pathogenetic mechanism rather than distinct pathogenesis, leadingto the hypothesis that both diseases are part of a unified syndrome, termed "Fisher-Bickerstaff syndrome". The subsequent identification of atypical anti-GQ1b-positive forms expanded the classification to a broader condition known as "Anti-GQ1b-Antibody syndrome"., Methods: An exhaustive literature review was conducted, analyzing a substantial body of research spanning from the initialdescriptions of the syndrome's components to recent developments in diagnostic classification and researchperspectives., Results: Anti-GQ1b syndrome encompasses a continuous spectrum of conditions defined by a common serological profilewith varying degrees of peripheral (PNS) and central nervous system (CNS) involvement. MFS and BBE represent theopposite ends of this spectrum, with MFS primarily affecting the PNS and BBE predominantly involving the CNS.Recently identified atypical forms, such as acute ophthalmoparesis, acute ataxic neuropathy withoutophthalmoparesis, Guillain-Barré syndrome (GBS) with ophthalmoparesis, MFS-GBS and BBE-GBS overlap syndromes,have broadened this spectrum., Conclusion: This work aims to provide an extensive, detailed, and updated overview of all aspects of the anti-GQ1b syndromewith the intention of serving as a stepping stone for further shaping thereof. Special attention was given to therecently identified atypical forms, underscoring their significance in redefining the boundaries of the syndrome., (© 2024. Fondazione Società Italiana di Neurologia.)

Blastic Plasmacytoid Dendritic Cell Neoplasms (BPDCNs) are a rare, highly aggressive hematological malignant neoplasm that primarily involve the skin, bone marrow, lymph nodes and even extra-nodal sites. The rarity and relative poor description of cases in the literature make it necessary to review and further studies that deeply investigate this entity not only in a histopathological but also molecular field. In August-September 2023, we searched MEDLINE, PubMed and Scopus for randomized controlled trials (RCTs), narrative and systematic reviews, meta-analyses, observational studies (either longitudinal or retrospective), and case series published in English in the last 25 years using the keywords BPDCN, PDCs, Blastic NK-cell lymphoma, agranular CD4+ NK leukemia/lymphoma, agranular CD4+ CD56+ hematodermic neoplasm/tumor. Despite the progress made in recent years in the diagnosis and biological understanding of the disease, until 2018 there was no clear consensus regarding its treatment and the main therapeutic schemes used were based on chemotherapy regimens already used in the treatment of lymphomas, acute lymphoblastic leukemia (ALL) and/or acute myeloid leukemia (AML). In this narrative review, we address the definition and epidemiological features of BPDCN, provide the different theories on the etiopathogenesis with particular attention to the presumed cell of origin, discuss the main clinical manifestations that provide a sign of its presence, summarize the main histopathological and immunophenotypic characteristics with special attention to the most important markers, and finally, we provide some of the most effective information on the therapeutic treatment modalities of BPDCN.