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In the last decade, the development of new radiopharmaceuticals for the imaging and therapy of prostate cancer has been a highly active and important area of research, especially focusing on the prostate-specific membrane antigen (PSMA), an antigen which is upregulated in prostate, as well as in other tumor cells. A large variety of PSMA ligands have been radiolabeled, to date. Among the various derivatives, PSMA-617 resulted to be one of the most interesting in terms of interaction with the antigen and clinical properties, and its lutetium-177 labeled version has recently been approved by regulatory agencies for therapeutic purposes. For this reasons, the radiolabeling with fluorine-18 of a PSMA-617 derivative might be of interest. Beside other methodologies to radiolabel macromolecules with fluorine-18, the “click-chemistry” approach resulted to be very useful, and the copper-catalyzed azide-alkyne cycloaddition (CuAAC) is considered one of most efficient and reliable. This paper proposes the synthesis of a suitable precursor for the radiolabeling with fluorine-18 of a new PSMA-617 derivative. The whole radiosynthetic procedure has been fully automated, and the final product, which proved to be stable in plasma, has been obtained with radiochemical yield and purity suitable for subsequent preclinical studies.  相似文献   
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AIDS and Behavior - People living with chronic disease (PLWCD) are the frailest category, both for the risk of severe COVID-19 illness and for the impact on the care continuum. Aim of this study...  相似文献   
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Zumel-Marne  Angela  Kundi  Michael  Castaño-Vinyals  Gemma  Alguacil  Juan  Petridou  Eleni Th  Georgakis  Marios K.  Morales-Suárez-Varela  Maria  Sadetzki  Siegal  Piro  Sara  Nagrani  Rajini  Filippini  Graziella  Hutter  Hans-Peter  Dikshit  Rajesh  Woehrer  Adelheid  Maule  Milena  Weinmann  Tobias  Krewski  Daniel  ′t Mannetje  Andrea  Momoli  Franco  Lacour  Brigitte  Mattioli  Stefano  Spinelli  John J.  Ritvo  Paul  Remen  Thomas  Kojimahara  Noriko  Eng  Amanda  Thurston  Angela  Lim  Hyungryul  Ha  Mina  Yamaguchi  Naohito  Mohipp  Charmaine  Bouka  Evdoxia  Eastman  Chelsea  Vermeulen  Roel  Kromhout  Hans  Cardis  Elisabeth 《Journal of neuro-oncology》2020,147(2):427-440
Journal of Neuro-Oncology - We used data from MOBI-Kids, a 14-country international collaborative case–control study of brain tumors (BTs), to study clinical characteristics of the tumors in...  相似文献   
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ObjectiveAcute food protein-induced enterocolitis syndrome (FPIES) is characterized by delayed repetitive vomiting after ingestion of a trigger food, and severe reactions may lead to dehydration, hypotension, and shock. We provide recommendations on management of FPIES emergencies in a medical facility and at home.Data SourcesThis review summarizes the literature on clinical context, pathophysiology, presentation, and treatment of FPIES emergencies.Study SelectionsWe referred to the 2017 International Consensus Guidelines for the Diagnosis and Management of FPIES and performed a literature search identifying relevant recent primary articles and review articles on clinical management.ResultsManagement of FPIES emergencies in a medical facility is based on severity of symptoms and involves rehydration, ondansetron, and corticosteroids. A proactive approach for reactions occurring at home involves prescribing oral ondansetron and providing an individualized treatment plan based on the evolution of symptoms and severity of past reactions. A better understanding of the pathophysiology of FPIES and randomized trials on ondansedron and cocorticosteroid use could lead to more targeted treatments.ConclusionChildren with FPIES are at risk for severe symptoms constituting a medical emergency. Management of FPIES emergencies is largely supportive, with treatment tailored to the symptoms, severity of the patient’s condition, location of reaction, and reaction history.  相似文献   
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The development of patient‐specific induced pluripotent stem cells (iPSCs) offered interesting insights in modeling the pathogenesis of Charcot‐Marie‐Tooth (CMT) disease and thus we decided to explore the phenotypes of iPSCs derived from a single CMT patient carrying a mutant ATP1A1 allele (p.Pro600Ala). iPSCs clones generated from CMT and control fibroblasts, were induced to differentiate into neural precursors and then into post‐mitotic neurons. Control iPSCs differentiated into neuronal precursors and then into post‐mitotic neurons within 6‐8 days. On the contrary, the differentiation of CMT iPSCs was clearly defective. Electrophysiological properties confirmed that post‐mitotic neurons were less mature compared to the normal counterpart. The impairment of in vitro differentiation of CMT iPSCs only concerned with the neuronal pathway, because they were able to differentiate into mesendodermal cells and other ectodermal derivatives. ATP1A1 was undetectable in the few neuronal cells derived from CMT iPSCs. ATP1A1 gene mutation (p.Pro600Ala), responsible for a form of axonal CMT disease, is associated in vitro with a dramatic alteration of the differentiation of patient‐derived iPSCs into post‐mitotic neurons. Thus, the defect in neuronal cell development might lead in vivo to a decreased number of mature neurons in ATP1A1‐CMT disease.  相似文献   
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BackgroundThe present analysis aims to compare the impact of 18F-fluorocholine (18F-choline) and gallium-68 prostate-specific membrane antigen (68Ga-PSMA) positron emission tomography (PET)-computed tomography (CT)–guided metastases-directed therapies (MDTs) in patients with castration-sensitive oligorecurrent prostate cancer (PC).Materials and MethodsInclusion criteria were: (1) histologically proven prostate adenocarcinoma; (2) evidence of biochemical relapse after primary tumor treatment; (3) ≤ 3 hypermetabolic oligorecurrent lesions detected by 18F-choline or 68Ga-PSMA PET-CT; (4) PET-CT imaging performed in a single nuclear medicine department; (5) patients treated with upfront stereotactic body radiotherapy (SBRT) without hormone therapy; and (6) SBRT delivered with a dose per fraction ≥ 5 Gy. In the case of oligoprogression (≤ 3 lesions outside the previous RT field) after MTD, a further course of SBRT was proposed; otherwise, androgen deprivation therapy (ADT) was administered.ResultsA total of 118 lesions in 88 patients were analyzed. Forty-four (50%) patients underwent 68Ga-PSMA PET-guided SBRT, and the remaining underwent choline PET-based SBRT. The median follow-up was 25 months (range, 5-87 months) for the entire cohort. Overall survival and local control were both 100%. Distant progression occurred in 48 (54.5%) patients, for a median distant progression-free survival of 22.8 months (range, 14.4-28.8 months). The median pre-SBRT prostate-specific antigen was 2.04 ng/mL in the choline PET cohort and 0.58 ng/mL in the PSMA-PET arm. Disease-free survival rates were 63.6% and 34%, respectively, in the 68Ga-PSMA and choline PET group (P = .06). The ADT administration rate was higher after choline-PET–guided SBRT (P = .00) owing to the higher incidence of polymetastatic disease after first-course SBRT compared with 68Ga-PSMA-based SBRT.ConclusionIn the setting of oligorecurrent castration-sensitive PC, PSMA-PET-guided SBRT produced a higher rate of ADT-free patients when compared with the 18F-choline-PET cohort. Randomized trials are advocated.  相似文献   
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BACKGROUND Coronavirus disease 2019(COVID-19) significantly affected endoscopy practice,as gastrointestinal endoscopy is considered a risky procedure for transmission of infection to patients and personnel of endoscopy units(PEU).AIM To assess the impact of COVID-19 on endoscopy during the first European lockdown(March-May 2020).METHODS Patients undergoing endoscopy in nine endoscopy units across six European countries during the period of the first European lockdown for COVID-19(MarchMay 2020) were included. Prior to the endoscopy procedure, participants were stratified as low-or high-risk for potential COVID-19 infection according to the European Society of Gastrointestinal Endoscopy(ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates(ESGENA) joint statement, and contacted 7-14 d later to assess COVID-19 infection status. PEU were questioned regarding COVID-19 symptoms and/or infection via questionnaire, while information regarding hospitalizations, intensive care unitadmissions and COVID-19-related deaths were collected. The number of weekly endoscopies at each center during the lockdown period was also recorded.RESULTS A total of 1267 endoscopies were performed in 1222 individuals across nine European endoscopy departments in six countries. Eighty-seven(7%) were excluded because of initial positive testing. Of the 1135 pre-endoscopy low risk or polymerase chain reaction negative for COVID-19, 254(22.4%) were tested post endoscopy and 8 were eventually found positive, resulting in an infection rate of 0.7% [(95%CI: 0.2-0.12]. The majority(6 of the 8 patients, 75%) had undergone esophagogastroduodenoscopy. Of the 163 PEU, 5 [3%;(95%CI: 0.4-5.7)] tested positive during the study period. A decrease of 68.7%(95%CI: 64.8-72.7) in the number of weekly endoscopies was recorded in all centers after March 2020. All centers implemented appropriate personal protective measures(PPM) from the initial phases of the lockdown.CONCLUSION COVID-19 transmission in endoscopy units is highly unlikely in a lockdown setting, provided endoscopies are restricted to emergency cases and PPM are implemented.  相似文献   
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