1,720,971 research outputs found
Personalization of radioiodine treatment for Graves' disease: a prospective, randomized study with a novel method for calculating the optimal 131I-iodide activity based on target reduction of thyroid mass.
No full text
Mesolimbic dopaminergic dysfunction in Parkinson's disease depression: evidence from a 123I-FP-CIT SPECT investigation.
No full textAbstract We investigated the striatal and extrastriatal
DAT availability (SPM8) by [123I]FP-CIT-SPECT in 15
PD patients with depression and 35 PD patients without
depression. A cluster with significant (p\0.05) lower
tracer binding in PD with depression was found in left
cingulate cortex, persistent after correction for age, disease
severity and duration, and inversely correlated with
depression scores (r -0.336, p\0.05). Our data indicate a
significant association between PD depression and cingulate
dopaminergic denervation supporting the dopaminergic
hypothesis of PD depression
Metastasis of renal cell carcinoma to the parathyroid gland 16 years after radical nephrectomy: A case report
No full textRenal cell carcinoma (RCC) has a high metastatic potential, and most commonly metastasizes via the bloodstream, although lymphatic metastases also occur. RCC is well-known for its propensity to metastasize to unusual sites, and late metastasis, even after a number of years, is common. The occurrence of RCC metastasis to the head and neck region is uncommon, and occurs primarily in the thyroid gland and in patients with widespread dissemination. Involvement of the parathyroid gland in metastatic carcinoma is extremely rare. In the present report, a case of metastasis confined to the parathyroid gland is described, likely with intrathyroidal localization, arising from a RCC that occurred 16 years after nephrectomy. A 66-year-old man was referred to the Department of Surgery of the University Hospital of Pisa (Pisa, Italy) with a preoperative fineneedle aspiration diagnosis of a follicular lesion in the context of nodular goiter of the thyroid gland. The previous medical history of the patient included a right nephrectomy for the treatment of clear cell RCC in February 1997. No other distant metastases were identified as of the latest followup in March 2014. At the time of thyroid surgery, the thyroid and parathyroid function tests were normal. The gross appearance of the surgical specimen was a multinodular goiter with a solid nodule measuring 33 mm on the left lobe of the thyroid gland. Microscopic examination revealed a completely encapsulated lesion consisting of clear cells arranged in a solid pattern and intermixed with fragments of parathyroid tissue. Following immunohistochemical examination, the clear cell lesion was negative for thyroid transcription factor-1 and thyroglobulin and strongly positive for epithelial membrane antigen, cluster of differentiation 10 and vimentin. To the best of our knowledge,this is the second case of metastasis to the parathyroid gland from a RCC reported in the literature
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
La Radioembolizzazione nel Colangiocarcinoma Intraepatico non operabile: studio dosimetrico e valutazione della risposta terapeutica
No full textIl colangiocarcinoma intraepaticoepatico (ICC) è il secondo tumore epatico primario più comune e, sebbene raro, sta registrando una crescente incidenza nel Nord America e in Europa. L’ICC ha una prognosi molto infausta con una mediana sopravvivenza se non trattato da 3 a 8 mesi; se trattato con terapie locali la sopravvivenza arriva anche fino a 15 mesi, mentre è di circa 12 mesi se trattato con terapie sistemiche. La radioembolizzazione epatica per via intrarteriosa (TARE) con Ittrio-90 fa parte delle terapie loco regionali per il trattamento dei ICC, indicato in pazienti non operabili (Stadio III e Stadio IV) e con malattia confinata all’organo. E’ una procedura in cui vengono iniettate tramite un accesso percutaneo, per via intra-arteriosa, particelle embolizzanti marcate con un radioisotopo. Le microsfere marcate con Ittrio-90 che è un Beta emittente puro, vanno a localizzarsi preferenzialmente a livello del microcircolo tumorale, dove esplicano la loro azione terapeutica.
Scopo: scopo di questa tesi è stato di valutare tutti i trattamenti TARE eseguiti presso AOUP in pazienti con ICC dal 2012 a oggi, e valutare l’efficacia del trattamento mediante l’utilizzo dei modelli radiobiologici di riferimento (il modello lineare-quadratico).
Materiali e metodi: sono stati trattati 26 pazienti con ICC inoperabile per un totale di 33 procedure. Sette dei ventisei pazienti (26.9%) avevano ricevuto come primo trattamento quello di TARE i restanti 19 pazienti erano stati sottoposti ad altri trattamenti locali e sistemici. Il calcolo dell’attività di microsfere di Ittrio-90 da somministrare per il trattamento è stato effettuato in tutti i pazienti con il metodo così detto della BSA. E’ stata eseguita una dosimetria 3d utilizzando le immagini PET/TC post trattamento con Ittrio-90 per calcolare la dose media assorbita dal tumore. La risposta in termini di riduzione volumetrica del tumore è stata valutata mediante TC dopo 1 mese dal trattamento e successivamente ad intervalli di 3 mesi. Abbiamo utilizzato il modello lineare quadratico semplificato per stimare il parametro radiobiologico Alpha attraverso il quale abbiamo potuto valutare teoricamente l’efficacia del trattamento a livello locale.
Risultati: Sulla base del metodo della BSA per il calcolo dell’attività da iniettare, nei 33 trattamenti TARE effettuati sono stati somministrati 969±330 MBq (media±DS) di microsfere di Ittrio-90. La valutazione della risposta al trattamento è stata effettuata su tutte le lesioni incluse nel trattamento utilizzando i criteri RECIST 1.1 basati sulla TC con mdc. La migliore risposta in termini di riduzione volumetrica del tumore è avvenuta in un intervallo temporale medio di 128±90 giorni dal trattamento TARE . Sono stati osservati 7 casi (21.2%) di risposta parziale, 17 casi (51.5%) di stabilità di malattia e 9 (casi 27%) di progressione tumorale. Il volume del tumore è risultato significativamente (t-test p <0,05) ridotto dopo il trattamento TARE (94 ±117 cc). La durata media del follow-up è stata di 12,5 ±7,9 mesi(mediana 12,9 mesi). Durante il follow-up 19 pazienti hanno presentato progressione della malattia epatica e 21 hanno messo in evidenza progressione della malattia a livello extra-epatico. All’ultimo follow-up (30 maggio 2018), sono stati registrati 13 decessi (50 %),mentre i restanti 13 pazienti (50%) sono tuttora in follow-up. La mediana di sopravvivenza è risultata di 20,2 mesi (IC 95% 14,7-50,8 mesi) dal trattamento TARE. Sebbene non sia stata osservata una differenza statisticamente significativa, la mediana di sopravvivenza dei pazienti che presentavano una PD al momento del controllo TC a un mese dal trattamento TARE risultava di 15,6 (IC 95% 2,5-20,2 mesi) mesi, a fronte di una sopravvivenza media dei pazienti con SD e PR di 20,2 (IC 95% 11,1 - ∞ mesi) e 28,2 mesi (IC 95% 8,1-28,2 mesi), rispettivamente. Abbiamo provato a valutare l’efficacia del trattamento mediante l’utilizzo dei modelli radiobiologici di riferimento (il modello lineare-quadratico). Utilizzando i dati a nostra disposizione (massa iniziale del tumore, massa finale del tumore, dose assorbita dal tumore) abbiamo stimato il parametro radiobiologico Alpha (che rappresenta la risposta del tessuto tumorale alle radiazioni ionizzanti). In tal modo abbiamo osservato come il Tumor Control Probability (TCP) sia molto bassa, ipotizzando quindi che la dose assorbita dal tessuto tumorale non sia sufficiente per controllare localmente la malattia.
Conclusioni: La nostra esperienza preliminare, in accordo con i dati della letteratura, conferma la sicurezza del trattamento di radioembolizzazione epatica in pazienti con ICC. Può rappresentare pertanto una valida opzione terapeutica in pazienti in stadio avanzato di malattia. Inoltre questo studio dimostra come l’attività somministrata secondo il metodo del BSA sottostima la dose assorbita dal tumore necessaria per controllare la malattia locale. Studi futuri devono essere eseguiti in tal senso per confermare questo dati preliminari
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Performance of Whole-Body Integrated 18F-FDG PET/MR in Comparison to PET/CT in Patients with Head and Neck Squamous Cell Carcinoma.
No full textAim of this study was to evaluate the performance of PET/MR in patients with Head and Neck Cancer including in the evaluation an acquisition protocol which we composed for this new modalities and a comparison of the quantification ability of the new device in terms of standardized uptake value (SUV) and its diagnostic outcome with that of PET/CT. The study population comprised 28 patients with head and neck cancer who underwent a single-injection dual imaging protocol with PET/CT and subsequent PET/MR. PET/CT scans were performed applying standard clinical protocols. Subsequently PET/MR was performed using whole-body Dixon MR-sequence for attenuation correction and a dedicated protocol for the neck. Artifacts and image quality, Intensity of [18F] FDG uptake, delineation, lesion characterization of all primary or recurrent tumours and cervical lymph nodes detected in PET/CT and PET/MR were analyzed and compared. Further SUVs for suspicious lesions in the head and neck and normal cervical muscles calculated in the two different modalities were compared. Histopathology, imaging and clinical follow-up data were used as reference standards for the final lesions' classification.
Artifacts and image quality was better for PET/MR than for PET/CT with statistically significant difference (p=0.004). Mean delineation of primary/recurrent and lymph nodes concerning intensity of FDG uptake was similar for PET/MR and PET/CT, while PET/MR allowed statistically higher delineation of primary/recurrent and metastatic lymph nodes than PET/CT.
PET/MR characterization of primary/recurrent tumour resulted in 100% sensitivity and 75% specificity while sensitivity and specificity of PET/CT was 90.9% and 75% respectively. No substantial differences in sensitivity and specificity between PET/MR and PET/CT were observed concerning characterization of cervical lymph nodes.
Quantitative analysis revealed highly significant correlations between maximum and mean SUVs of all lesions evaluated at PET/CT and PET/MR.
SUVmean and SUVmax were significantly higher in PET/MR than PET/CT for tumour lesions, while were significantly lower in PET/MR than PET/CT for cervical normal muscles.
Conclusion: Simultaneous PET/MR acquisition was feasible and delivered in a reasonable acquisition time high quality, diagnostically sufficient PET and MR data. In particular, our data indicate that the combination of MR and PET was beneficial especially for assessment of the primary or recurrent tumour. Moreover, results of the quantitative analysis show that SUVs derived from [18F] FDG-positive lesions on PET/MR and in normal cervical muscles correlated well with those derived from PET/CT
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