307 research outputs found
Magnetron High Power System Design
This paper describes the design of an X-Band Magnetron to Linear Accelerator (LINAC) High Power Transfer System consisting in an 8 resonant cavities Magnetron connected to a dedicated vacuum Dielectric Window (DW). A main analytical design of devices is shown with compact formulas and is followed by numerical optimization. Electromagnetic and Thermomechanical coupling between these devices is described, particular attention has been given to the Magnetron power coupling and DW matching. A Multiphysics modeling is proposed to consider thermal-structural effects due to the cathode heating for the Magnetron and the Joule effect for the DW. Thermal induced degradation of the device performances are estimated and proper
materials and shapes are chosen in order to ensure the desired behavior of the system in operative conditions. The proposed study provided the evaluation of the Magnetron Working Points and DW Scattering parameters in Thermo-mechanical operative conditions. Technological strategies for device coupling are shown
Depuration Capacity of Mussels (Mytilus galloprovincialis) in Presence of Marteilia Spp. Parasites
Bivalve molluscs are filter-feeding organisms present in the water column: during their activity, they could retain
micro-organisms that are potentially dangerous to human health. For this reason, EU Regulations may require that
a purification treatment be performed prior to bivalve trade. The length of the purification process could be affected
by stress factors, such as parasitic infections. The purpose of this study was to determine if the presence of Marteilia
spp. parasite in shellfish could modify time and efficacy of their microbiological purification treatment, in order to
set up specific protocols. Lysosomal membrane stability, phagocytosis capacity, granulocyte/hyalinocyte rate and
neutral lipid accumulation are biomarkers used to evaluate shellfish physiological state. These biomarkers were
used to exclude any differences caused by stressor factors that could affect the purification results. Mussels were
sampled from two different production areas. The presence or absence of parasites was confirmed by cytological test.
Both groups of parasitized and non-parasitized mussels were contaminated with E.coli: they were then sampled for
microbiological analyses and tested for biomarkers for up to 70 hours of purification. Parasitized and non-parasitized
molluscs did not show any differences in levels of E. coli after 12, 24, 36, 48 and 70 hours of depuration. In relation
to biomarkers, mussels seem to react to Lysosomal membrane stability in presence of Marteilia. The present study
shows that the presence of Marteilia spp. does not affect the purification rate of mussels
Onset and Progression of Precancerous Lesions on Gastric Mucosa of Patients Treated for Gastric Lymphoma.
Background and Aims: Patients with primary gastric lymphoma are at an increased risk of developing gastric cancer. Data on gastric precancerous lesions development in these patients are scanty. We assessed gastric precancerous lesions in a cohort of patients with primary lymphoma.
Methods: Data of patients with primary gastric lymphoma [mucosa-associated lymphoid tissue (MALT)- lymphoma or diffuse large B-cell lymphoma (DLBCL)] were analysed. Multiple (>10) biopsies were performed on gastric mucosa at each endoscopic control, beyond macroscopic lesions. Presence and distribution of intestinal metaplasia (IM) at baseline, the onset at follow-up, and progression through the stomach or transformation in the incomplete IM type were assessed. The onset of neoplastic lesions was recorded.
Results: Data of 50 patients (mean age of 63.6 ± 10.7 years; M/F: 25/25), including 40 with MALT-lymphoma and 10 with DLBCL, with median follow-up of 30.5 months (range: 9-108) and a median of 6 endoscopic controls (range: 3-14) were evaluated. At entry, IM was present in 12 (24%), and it developed in other 22 (57.9%) patients at a median follow-up of 6 (range: 3-40) months. Overall, progression of IM was observed in 7 (21.2%) cases, including extension in the stomach (n=5) or transformation into the incomplete type (n=2). Low-grade dysplasia was detected in 4, and indefinite dysplasia in other 7 patients. In one patient, low-grade dysplasia had progressed to high-grade and gastric adenocarcinoma of the fundus.
Conclusions: Our data found a frequent onset and rapid progression of precancerous lesions on gastric mucosa of lymphoma patients. This observation could explain the increased incidence of metachronous gastric cancer in these patients
Complications of extraperitoneal robot-assisted radical prostatectomy in high-risk prostate cancer: A single high-volume center experience
IntroductionThe role of robot-assisted radical prostatectomy (RARP) in high-risk prostate cancer (PCa) has been debated over the years, but it appears safe and effective in selected patients. While the outcomes of transperitoneal RARP for high-risk PCa have been already widely investigated, data on the extraperitoneal approach are scarcely available. The primary aim of this study is to evaluate intra- and postoperative complications in a series of patients with high-risk PCa treated by extraperitoneal RARP (eRARP) and pelvic lymph node dissection. The secondary aim is to report oncological and functional outcomes.MethodsData of patients who underwent eRARP for high-risk PCa were prospectively collected from January 2013 to September 2021. Intraoperative and postoperative complications were recorded, as also perioperative, functional, and oncological outcomes. Intraoperative and postoperative complications were classified by employing Intraoperative Adverse Incident Classification by the European Association of Urology and the Clavien–Dindo classification, respectively. Univariate and multivariate analyses were performed to evaluate a potential association between clinical and pathological features and the risk of complications.ResultsA total of 108 patients were included. The mean operative time and estimated blood loss were 183.5 ± 44 min and 115.2 ± 72.4 mL, respectively. Only two intraoperative complications were recorded, both grade 3. Early complications were recorded in 15 patients, of which 14 were of minor grade, and 1 was grade IIIa. Late complications were diagnosed in four patients, all of grade III. Body mass index (BMI) > 30 kg/m2, Prostate-Specific Antigen (PSA) > 20 ng/mL, PSA density >0.15 ng/mL2, and pN1 significantly correlated with a higher rate of overall postoperative complications. Moreover, BMI >30 kg/m2, PSA >20 ng/mL, and pN1 significantly correlated with a higher rate of early complications, while PSA >20 ng/mL, prostate volume <30 mL, and pT3 were significantly associated with a higher risk of late complications. In multivariate regression analysis, PSA >20 ng/mL significantly correlated with overall postoperative complications, while PSA > 20 and pN1 correlated with early complications. Urinary continence and sexual potency were restored in 49.1%, 66.7%, and 79.6% of patients and in 19.1%, 29.9%, and 36.2% of patients at 3, 6, and 12 months, respectively.ConclusionseRARP with pelvic lymph node dissection in patients with high-risk PCa is a feasible and safe technique, resulting in only a few intra- and postoperative complications, mostly of low grade
Clinical recommendations for diagnosis and treatment according to current updated knowledge on BIA-ALCL
Shared strategies and correct information are essential to guide physicians in the management of such an uncommon disease as Breast Implant-Associated Anaplastic Large Cell Lymphoma (BIA-ALCL). A systematic review of the literature was performed to collect the most relevant evidence on BIA-ALCL reported cases. A panel of multidisciplinary experts discussed the scientific evidence on BIA-ALCL, and updated consensus recommendations were developed through the Delphi process. The lastest reported Italian incidence of BIA-ALCL is 3.5 per 100.000 implanted patients (95% CI, 1.36 to 5.78), and the disease counts over 1216 cases worldwide as of June 2022. The most common presentation symptom is a late onset seroma followed by a palpable breast mass. In the event of a suspicious case, ultrasound-guided fine-needle aspiration should be the first step in evaluation, followed by cytologic and immunohistochemical examination. In patients with confirmed diagnosis of BIA-ALCL confined to the capsule, the en-bloc capsulectomy should be performed, followed by immediate autologous reconstruction, while delayed reconstruction applies for disseminate disease or radically unresectable tumor. Nevertheless, a multidisciplinary team approach is essential for the correct management of this pathology
Selection, affinity maturation, and characterization of a human scFv antibody against CEA protein
BACKGROUND: CEA is a tumor-associated antigen abundantly expressed on several cancer types, including those naturally refractory to chemotherapy. The selection and characterization of human anti-CEA single-chain antibody fragments (scFv) is a first step toward the construction of new anticancer monoclonal antibodies designed for optimal blood clearance and tumor penetration. METHODS: The human MA39 scFv, selected for its ability to recognize a CEA epitope expressed on human colon carcinomas, was first isolated from a large semi-synthetic ETH-2 antibody phage library, panned on human purified CEA protein. Subsequently, by in vitro mutagenesis of a gene encoding for the scFv MA39, a new library was established, and new scFv antibodies with improved affinity towards the CEA cognate epitope were selected and characterized. RESULTS: The scFv MA39 antibody was affinity-maturated by in vitro mutagenesis and the new scFv clone, E8, was isolated, typed for CEA family member recognition and its CEACAM1, 3 and 5 shared epitope characterized for expression in a large panel of human normal and tumor tissues and cells. CONCLUSION: The binding affinity of the scFv E8 is in a range for efficient, in vivo, antigen capture in tumor cells expressing a shared epitope of the CEACAM1, 3 and 5 proteins. This new immunoreagent meets all criteria for a potential anticancer compound: it is human, hence poorly or not at all immunogenic, and it binds selectively and with good affinity to the CEA epitope expressed by metastatic melanoma and colon and lung carcinomas. Furthermore, its small molecular size should provide for efficient tissue penetration, yet give rapid plasma clearance
FLASH radiotherapy with electrons: issues related to the production, monitoring, and dosimetric characterization of the beam
Various in vivo experimental works carried out on different animals and organs have shown that it is possible to reduce the damage caused to healthy tissue still preserving the therapeutic efficacy on the tumor tissue, by drastically reducing the total time of dose delivery (<200 ms). This effect, called the FLASH effect, immediately attracted considerable attention within the radiotherapy community, due to the possibility of widening the therapeutic window and treating effectively tumors which appear radioresistant to conventional techniques. Despite the experimental evidence, the radiobiological mechanisms underlying the FLASH effect and the beam parameters contributing to its optimization are not yet known in details. In order to fully understand the FLASH effect, it might be worthy to investigate some alternatives which can further improve the tools adopted so far, in terms of both linac technology and dosimetric systems. This work investigates the problems and solutions concerning the realization of an electron accelerator dedicated to FLASH therapy and optimized for in vivo experiments. Moreover, the work discusses the saturation problems of the most common radiotherapy dosimeters when used in the very high dose-per-pulse FLASH conditions and provides some preliminary experimental data on their behavior
Corrigendum: FLASH Radiotherapy With Electrons: Issues Related to the Production, Monitoring, and Dosimetric Characterization of the Beam
In the original article, the following authors were missing: Luigi Faillace, Lucia Giuliano, Mauro Migliorati, Luigi Palumbo. The corrected Author Contributions statement appears below. Affiliation 3, ‘Sapienza University of Rome, Rome, Italy’, is also added for authors LF, LG, MM, and LP. The authors apologize for these errors and state that this does not change the scientific conclusions of the article in any way. The original article has been updated
WHO standards-based tools to measure service providers' and service users' views on the quality of hospital child care: development and validation in Italy
Objectives Evidence showed that, even in high-income countries, children and adolescents may not receive high quality of care (QOC). We describe the development and initial validation, in Italy, of two WHO standards-based questionnaires to conduct an assessment of QOC for children and young adolescents at inpatient level, based on the provider and user perspectives. Design Multiphase, mixed-methods study. Setting, participants and methods The two questionnaires were developed in four phases equally conducted for each tool. Phase 1 which included the prioritisation of the WHO Quality Measures according to predefined criteria and the development of the draft questionnaires. In phase 2 content face validation of the draft questionnaires was assessed among both experts and end-users. In phase 3 the optimised questionnaires were field tested to assess acceptability, perceived utility and comprehensiveness (N=163 end-users). In phase 4 intrarater reliability and internal consistency were evaluated (N=170 and N=301 end-users, respectively). Results The final questionnaires included 150 WHO Quality Measures. Observed face validity was excellent (kappa value of 1). The field test resulted in response rates of 98% and 76% for service users and health providers, respectively. Among respondents, 96.9% service users and 90.4% providers rated the questionnaires as useful, and 86.9% and 93.9%, respectively rated them as comprehensive. Intrarater reliability was good, with Cohen's kappa values exceeding 0.70. Cronbach alpha values ranged from 0.83 to 0.95, indicating excellent internal consistency. Conclusions Study findings suggest these tools developed have good content and face validity, high acceptability and perceived utility, and good intrarater reliability and internal consistency, and therefore could be used in health facilities in Italy and similar contexts. Priority areas for future research include how tools measuring paediatric QOC can be more effectively used to help health professionals provide the best possible care
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