954 resultados para PET Scan


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Gemcitabine is a chemotherapy agent that may cause unpredictable side effects. In this report, we describe a fatal gemcitabine-induced pulmonary toxicity in a patient with gallbladder metastatic adenocarcinoma. A 72-year-old patient was submitted to an elective laparoscopic cholecystectomy, and a tubular adenocarcinoma in the gallbladder was incidentally diagnosed. CT scan and ultrasound before the surgery did not show any tumor. After the surgery a Pet scan was positive for a hot-spot in the left colon. The colonic lesion was conveniently removed and the histology evaluation confirmed the diagnosis of adenocarcinoma tubular. The patient was then submitted to three sections of 1,600 mg/m(2) of gemcitabine with intervals of 1 week. Three weeks later he developed severe respiratory distress. A helicoidal CT scan showed diffuse and severe interstitial pneumonitis, and lung biopsy confirmed accelerated usual interstitial pneumonia consistent with drug-induced toxicity. The patient presented unfavorable evolution with progressive worsening of respiratory function, hypotension, and renal failure. He died 1 month later in spite of methylprednisolone pulse therapy, large spectrum antimicrobial therapy, and full support of respiratory, hemodynamic and renal systems. Gemcitabine-induced pulmonary toxicity is usually a dramatic condition. Physicians should suspect pulmonary toxicity in patients with respiratory distress after gemcitabine chemotherapy, mainly in elderly patients.

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RESUME Objectif : Les lymphomes épiduraux primaires représentent moins de 10% des tumeurs épidurales et de 0,1 à 3,3% de tous les lymphomes. Le but de cette étude a été d'évaluer le profil clinique de cette maladie rare, son traitement, ses résultats ainsi que ses facteurs de pronostic. Matériel et méthode : Entre 1982 et 2002, 52 patients présentant un lymphome épidural primaire ont été traités dans neuf institutions membres du Rare Cancer Network. Les critères d'inclusion comprenaient : une biopsie confirmant le lymphome non-hodgkinien, un stade IE et IIE selon la classification de Ann Arbor, un traitement à visée curative de radiothérapie combinée ou non à une chimiothérapie et un suivi d'au moins six mois. Selon la Working Formulation, 12 patients (23%) présentaient un lymphome de bas grade, 28 (54%) un grade intermédiaire et 12 (23%) un haut grade. Les hommes étaient atteints 1.9 fois plus fréquemment que les femmes. L'âge moyen était de 61 ans (intervalle : 21 à 96). Le bilan incluait un Ct-scan spinal (98%), une IRM (52%), un CT-scan thoraco-abdominal (77%) et une aspiration ou biopsie de moelle osseuse (96%). Les symptômes les plus fréquents comprenaient des douleurs dorsales (79% des patients), une faiblesse musculaire (92%) et des déficits sensoriels (71 %). Quarante-huit patients ont subi une laminectomie de décompression avec résection partielle ou complète (42% et 13% des cas respectivement), tous ont reçu une radiothérapie seule (20 patients) ou en combinaison avec une chimiothérapie (32 patients). La dose médiane totale était de 36 Gy (intervalle 6-50 Gy) avec une moyenne de 20 Gy par fraction (intervalle : 1-25). Le suivi moyen était de 71 mois (intervalle : 22-165 mois). Résultats : Suite au traitement, une progression locale a été observée chez 6 patients après un temps de latence moyen de 6 mois. Le taux de rechute systémique a été de 42% (22 patients) le plus souvent dans les ganglions lymphatiques (n=9) après un intervalle de temps moyen de 20 mois. Lors du dernier contrôle, 28 patients étaient vivants et 24 patients étaient décédés. Le taux de survie à 5 ans, le taux de survie sans maladie et le contrôle local étaient de 69%, 57% et 88% respectivement. En analyse univariée, les facteurs pronostics favorables statistiquement significatifs concernant la survie sans maladie étaient un âge inférieur à 63 ans, ainsi qu'une réponse neurologique complète. Pour la survie à 5 ans, les facteurs favorables étaient un âge inférieur à 63 ans. En analyse multivariée, les facteurs pronostics favorables pour la survie globale à 5 ans étaient une réponse neurologique complète, un traitement combiné, un volume de radiothérapie plus que focal, une dose totale de radiothérapie supérieure à 36 Gy et une résection partielle ou complète de la tumeur. En ce qui concerne la survie sans maladie, les facteurs pronostics favorables étáient un âge inférieur à 63 ans et un traitement combiné. Conclusion : Ce qui ressort de cette analyse est que le bilan diagnostic devrait inclure une IRM ou un CT-scan, un échantillon de tissu pour poser le diagnostic pathologique définitif de la lésion, une histoire médicale et un examen physique complet, une chimie sanguine, un CTscan thoraco-abdominal et une biopsie de la moelle osseuse, un PET-scan devrait également faire partie du bilan. Le traitement devrait consister, dans la phase aiguë, en une chirurgie de décompression avec ou sans résection, suivie d'une radiothérapie d'au moins 36Gy en 2 Gy par fraction et d'une chimiothérapie. Tous les patients présentant un lymphome de haut grade ou de grade intermédiaire devraient pouvoir bénéficier d'un traitement combiné.

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Résumé : Objectif: Analyse d'un traitement de chimiothérapie à base de cisplatine de type néoadjuvant en comparaison à un traitement de radio-chimiothérapie suivi de la résection chirurgicale chez des patients présentant un carcinome pulmonaire non à petites cellules de stade Ill (N2) prouvé histologiquement par médiastinoscopie. Evaluation de la morbidité postopératoire, du down-staging ganglionnaire, des taux de survie globale et sans récidive ainsi que du site de récidive. Matériel et méthodes : 82 patients ont été inclus dans l'étude entre Janvier 1994 et Juin 2003, parmi eux 36 ont été traités avec une chimiothérapie néoadjuvante à base de cisplatine et doxétacel (groupe l). Les autres 46 patients ont été soumis à une radio-chimiothérapie néoadjuvante avec administration de 44 Gy (groupe II), soit de façon séquentielle (25 cas) soit concomitante (21 cas). Dans tous les cas des métastases à distance ont été exclues par une évaluation préopératoire comprenant une scintigraphie osseuse, un Ct scan thoraco-abdominal, ou un examen PET scan ainsi qu'une IRM cérébrale. La médiastinoscopie effectuée avant le traitement d'induction chez la totalité des patients, de même que la résection chirurgicale de la tumeur pulmonaire et la lymphadenectomie médiastinale ont été effectuées par le même chirurgien. Résultats : La tumeur pulmonaire était de stade Ti à T2 dans respectivement 47% et 28% des patients des groupes (e II, T3 dans 45% et 41% et T4 dans 8% et 31% des cas. Le type de résection effectué (lobectomie, lobectomie en manchon, pneumonectomie) était comparable dans les deux collectifs (p=0.03) Le taux de mortalité postopératoire à 90 jours était de respectivement 3% et 4 "Vo (p=0.6). Une résection complète (RO) a pu être obtenue dans 92% et 94% des cas (p=0.6) avec un downstaging ganglionnaire médiastinal dans 61% et 78% des patients respectivement (p<0.001). Les taux de survie globale à 5 ans et de survie sans récidive à 5 ans s'élevaient à 40% et à 36% respectivement, sans différence significative entre des tumeurs de stade Ti à T3 et T4. Le taux de survie globale n'était pas significativement différent entre les deux modalités de traitement d'induction, toutefois après radio-chimiothérapie on observait une plus longue survie sans récidive (p.0.04). Il n'y avait par ailleurs pas de différence significative, en termes de morbidité post-opératoire, résecabilité, downstaging ganglionnaire, survie globale et sans récidive, entre les patients traités par radio-chimiothérapie séquentielle ou concomitante. Conclusions : En cas de carcinome pulmonaire non à petites cellules de stade III (N2) un traitement d'induction par radio chimiothérapie suivi de la résection chirurgicale est associé avec un meilleur downstaqing médiastinal ainsi qu'une plus longue survie sans récidive en comparaison au traitement d'induction par chimiothérapie seule. Abstract : Objective: Comparison of prospectively treated patients with neoadjuvant cisplatin-based chemotherapy vs radiochemotherapy followed by resection for mediastinoscopically proven stage III NZ non-small cell lung cancer with respect to postoperative morbidity, pathological nodal downstaging, overall and disease-free survival, and site of recurrence. Methods: Eighty-two patients were enrolled between January 1994 to June 2003, 36 had cisplatin and doxetacel-based chemotherapy (group I) and 46 cisplatin-based radiochemotherapy up to 44 Gy (group II), either as sequential (25 patients) or concomitant (21 patients) treatment. All patients had evaluation of absence of distant metastases by bone scintigraphy, thoracoabdominal CT scan or PET scan, and brain MRI, and all underwent pre-induction mediastinoscopy, resection and mediastinal lymph node dissection by the same surgeon. Results: Group I and II comprised T1/2 tumors in 47 and 28%, 13 tumors in 45 and 41%, and 14 tumors in 8 and 31% of the patients, respectively (P=0.03). There was a similar distribution of the extent of resection (lobectomy, sleeve lobectomy, left and right pneumonectomy) in both groups (P=0.9). Group I and II revealed a postoperative 90-d mortality of 3 and 4% (P=0.6), a RO-resection rate of 92 and 94% (P=0.9), and a pathological mediastinal downstaging in 61 and 78% of the patients (P<0.01), respectively. 5y-overall survival and disease-free survival of all patients were 40 and 36%, respectively, without significant difference between T1-3 and T4 tumors. There was no significant difference in overall survival rate in either induction regimens, however, radiochemotherapy was associated with a longer disease-free survival than chemotherapy (P=0.04). There was no significant difference between concurrent vs sequential radiochemotherapy with respect to postoperative morbidity, resectability, pathological nodal downstaging, survival and disease-free survival. Conclusions: Neoadjuvant cisplatin-based radiochemotherapy was associated with a similar postoperative mortality, an increased pathological nodal downstaging and a better disease-free survival as compared to cisplatin doxetacel-based chemotherapy in patients with stage III (N2) NSCLC although a higher number of 14 tumors were admitted to radiochemotherapy.

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BackgroundPulmonary Langerhans cell histiocytosis (PLCH) is a rare disorder characterised by granulomatous proliferation of CD1a-positive histiocytes forming granulomas within lung parenchyma, in strong association with tobacco smoking, and which may result in chronic respiratory failure. Smoking cessation is considered to be critical in management, but has variable effects on outcome. No drug therapy has been validated. Cladribine (chlorodeoxyadenosine, 2-CDA) down-regulates histiocyte proliferation and has been successful in curbing multi-system Langerhans cell histiocytosis and isolated PLCH.Methods and patientsWe retrospectively studied 5 patients (aged 37¿55 years, 3 females) with PLCH who received 3 to 4 courses of cladribine therapy as a single agent (0.1 mg/kg per day for 5 consecutive days at monthly intervals). One patient was treated twice because of relapse at 1 year. Progressive pulmonary disease with obstructive ventilatory pattern despite smoking cessation and/or corticosteroid therapy were indications for treatment. Patients were administered oral trimethoprim/sulfamethoxazole and valaciclovir to prevent opportunistic infections. They gave written consent to receive off-label cladribine in the absence of validated treatment.ResultsFunctional class dyspnea improved with cladribine therapy in 4 out of 5 cases, and forced expiratory volume in 1 second (FEV1) increased in all cases by a mean of 387 ml (100¿920 ml), contrasting with a steady decline prior to treatment. Chest high-resolution computed tomography (HRCT) features improved with cladribine therapy in 4 patients. Hemodynamic improvement was observed in 1 patient with pre-capillary pulmonary hypertension. The results suggested a greater treatment effect in subjects with nodular lung lesions and/or thick-walled cysts on chest HRCT, with diffuse hypermetabolism of lung lesions on positron emission tomography (PET)-scan, and with progressive disease despite smoking cessation. Infectious pneumonia developed in 1 patient, with later grade 4 neutrocytopenia but without infection.DiscussionData interpretation was limited by the retrospective, uncontrolled study design and small sample size.ConclusionCladribine as a single agent may be effective therapy in patients with progressive PLCH.

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OBJECTIVE: Comparison of prospectively treated patients with neoadjuvant cisplatin-based chemotherapy vs radiochemotherapy followed by resection for mediastinoscopically proven stage III N2 non-small cell lung cancer with respect to postoperative morbidity, pathological nodal downstaging, overall and disease-free survival, and site of recurrence. METHODS: Eighty-two patients were enrolled between January 1994 to June 2003, 36 had cisplatin and doxetacel-based chemotherapy (group I) and 46 cisplatin-based radiochemotherapy up to 44 Gy (group II), either as sequential (25 patients) or concomitant (21 patients) treatment. All patients had evaluation of absence of distant metastases by bone scintigraphy, thoracoabdominal CT scan or PET scan, and brain MRI, and all underwent pre-induction mediastinoscopy, resection and mediastinal lymph node dissection by the same surgeon. RESULTS: Group I and II comprised T1/2 tumors in 47 and 28%, T3 tumors in 45 and 41%, and T4 tumors in 8 and 31% of the patients, respectively (P=0.03). There was a similar distribution of the extent of resection (lobectomy, sleeve lobectomy, left and right pneumonectomy) in both groups (P=0.9). Group I and II revealed a postoperative 90-d mortality of 3 and 4% (P=0.6), a R0-resection rate of 92 and 94% (P=0.9), and a pathological mediastinal downstaging in 61 and 78% of the patients (P<0.01), respectively. 5y-overall survival and disease-free survival of all patients were 40 and 36%, respectively, without significant difference between T1-3 and T4 tumors. There was no significant difference in overall survival rate in either induction regimens, however, radiochemotherapy was associated with a longer disease-free survival than chemotherapy (P=0.04). There was no significant difference between concurrent vs sequential radiochemotherapy with respect to postoperative morbidity, resectability, pathological nodal downstaging, survival and disease-free survival. CONCLUSIONS: Neoadjuvant cisplatin-based radiochemotherapy was associated with a similar postoperative mortality, an increased pathological nodal downstaging and a better disease-free survival as compared to cisplatin doxetacel-based chemotherapy in patients with stage III (N2) NSCLC although a higher number of T4 tumors were admitted to radiochemotherapy.

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Purpose: Cardiac 18F-FDG PET is considered as the gold standard to assess myocardial metabolism and infarct size. The myocardial demand for glucose can be influenced by fasting and/or following pharmacological preparation. In the rat, it has been previously shown that fasting combined with preconditioning with acipimox, a nicotinic acid derivate and lipidlowering agent, increased dramatically 18F-FDG uptake in the myocardium. Strategies aimed at reducing infarct scar are evaluated in a variety of mouse models. PET would particularly useful for assessing cardiac viability in the mouse. However, prior knowledge of the best preparation protocol is a prerequisite for accurate measurement of glucose uptake in mice. Therefore, we studied the effect of different protocols on 18F-FDG uptake in the mouse heart.Methods: Mice (n = 15) were separated into three treatment groups according to preconditioning and underwent a 18FDG PET scan. Group 1: No preconditioning (n = 3); Group 2: Overnight fasting (n = 8); and Group 3: Overnight fasting and acipimox (25mg/kg SC) (n = 4). MicroPET images were processed with PMOD to determine 18F-FDG mean standard uptake value (SUV) at 30 min for the whole left ventricle (LV) and for each region of the 17-segments AHA model. For comparisons, we used Mann-Whitney test and multilevel mixed-effects linear regression (Stata 11.0).Results: In total, 27 microPET were performed successfully in 15 animals. Overnight fasting led to a dramatic increase in LV-SUV compared to mice without preconditioning (8.6±0.7g/mL vs. 3.7±1.1g/mL, P<0.001). In addition, LV-SUV was slightly but not significantly higher in animals treated with acipimox compared to animals with overnight fasting alone (10.2±0.5 g/mL, P = 0.06). Fastening increased segmental SUV by 5.1±0.5g/mL as compared to free-feeding mice (from 3.7±0.8g/mL to 8.8±0.4g/mL, P<0.001); segmental-SUV also significantly increased after administration of acipimox (from 8.8±0.4g/mL to 10.1±0.4g/mL, P<0.001).Conclusion: Overnight fasting led to myocardial glucose deprivation and increases 18F-FDG myocardial uptake. Additional administration of acipimox enhances myocardial 18F-FDG uptake, at least at the segmental level. Thus, preconditioning with acipimox may provide better image quality that may help for assessing segmental myocardial metabolism.

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Background: Cetuximab significantly enhances efficacy of radiotherapy and chemotherapy in head and neck cancer. We investigated the safety and feasibility of adding cetuximab to neoadjuvant chemoradiation of locally advanced esophageal cancer. Methods: Pts with resectable, locally advanced squamous cell carcinoma (SCC) or adenocarcinoma (AC) of the thoracic esophagus or gastroesophageal junction (staged by EUS, CT and PET scan) were treated with 2 cycles of induction chemotherapy (docetaxel 75mg/m2, cisplatin 75mg/m2 q3w and weekly cetuximab 250mg/m2), followed by concomitant chemo- immuno-radiation therapy (CIRT: docetaxel 20mg/m2, cisplatin 25mg/m2 and cetuximab 250mg/m2 weekly five times concomitant with 45 Gy radiotherapy in 25 fractions); followed by surgery 4-8 weeks later. The phase I part consisted of 2 cohorts of 7 patients each, without and with docetaxel during CIRT, respectively. Interpatient dose-escalation (adding docetaxel during CIRT) was possible if < 2 out of 7 pts of the 1st cohort experienced limiting toxicity. Having finished the phase 1 part, 13 additional patients were treated with docetaxel-containing CIRT in a phase II part. Pathological response was evaluated according to the Mandard classification. Results: 27 pts from 12 institutions were included. As of today, results from 20 pts are available (cohort 1: 7, cohort 2: 7, phase ll : 6). Median age was 64yrs (range 47-71). 11 AC; 9 SCC. 19 pts (95%) completed CIRT (1 pt stopped treatment during induction therapy due to sepsis). 17 pts underwent resection (no surgery: 1pt for PD, 1pt for cardiac reasons). Grade 3 toxicities during CIRT included anorexia 15%, dysphagia/esophagitis 15%, fatigue 10%, nausea 10%, pruritus 5%, dehydration 5%, nail changes 5% and rash 5% .1 pt suffered from pulmonary embolism. 13 pts (65%, intention-to-treat) showed a complete or near complete pathological remission (cohort 1: 5, cohort 2: 4, phase II: 4). Conclusions: Adding cetuximab to preoperative chemoradiation for esophageal cancer is safe and feasible in a community-based multicenter setting. Antineoplastic activity is encouraging with 65% pathological responders.

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T cell lymphoma of γδ T cell origin is a rare disease that mainly involves extranodal sites and shows aggressive clinical behavior. Here, we report a case of primary γδ T cell lymphoma of the lungs with epitheliotropism in the respiratory epithelium, a feature somewhat reminiscent of what is observed in enteropathy-associated T cell lymphoma. A 63-year-old man presented with chest pain and dyspnea on exertion, weight loss, and general weakness. On a positron emission tomography (PET) scan, multiple hypermetabolic lesions were found in both lungs. Microscopic examination of the wedge lung biopsy revealed nodular infiltration of monomorphic, medium- to large-sized atypical lymphocytes with round nuclei, coarse chromatin, and a variable amount of clear to eosinophilic cytoplasm. Of note, intraepithelial lymphocytosis by atypical lymphoid cells was observed in the respiratory epithelium within and around the nodule. Immunohistochemically, the tumor cells were CD3+, TCRβF1-, TCRγ+, CD5-, CD7+, CD20-, CD79a-, CD30-, CD4-, CD8-, CD10-, BCL6-, CD21-, CD56+, CD57-, and CD138-, and expressed cytotoxic molecules. Epstein-Barr virus (EBV) was not detected by an in situ hybridization assay for EBV-encoded RNA. Interestingly, CD103 was expressed by a subset of tumor cells, especially those infiltrating the epithelium. T cell clonality was detected by multiplex PCR analysis of TRG and TRD gene rearrangements. After 2 months of systemic chemotherapy, PET scan showed regression of the size and metabolic activity of the lesions. This case represents a unique γδ T cell lymphoma of the lungs showing epitheliotropism by CD103+ γδ T cells that is suggestive of tissue-resident γδ T cells as the cell of origin.

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AIM: To describe a large family with autosomal dominant parkinsonism. BACKGROUND: Seven genes are directly implicated in autosomally inherited parkinsonism. However, there are several multigenerational large families known with no identifiable mutation. MATERIAL AND METHODS: Family members were evaluated clinically, by history and chart review. Genetic investigation included SCA2, SCA3, UCHL1, SNCA, LRRK2, PINK1, PRKN, PGRN, FMR1 premutation, and MAPT. The proband underwent brain fluorodopa PET (FD-PET) scan, and one autopsy was available. RESULTS: Eleven patients had a diagnosis of Parkinson's disease (PD), nine women. Mean age of onset was 52 with tremor-predominant dopa-responsive parkinsonism. Disease progression was slow but severe motor fluctuations occurred. One patient required subthalamic nucleus deep-brain stimulation with a good motor outcome. One patient had mental retardation, schizophrenia and became demented, and another patient was demented. Three patients and also two unaffected subjects had mild learning difficulties. All genetic tests yielded negative results. FD-PET showed marked asymmetric striatal tracer uptake deficiency, consistent with PD. Pathological examination demonstrated no Lewy bodies and immunostaining was negative for alpha-synuclein. CONCLUSION: Apart from a younger age of onset and a female predominance, the phenotype was indistinguishable from sporadic tremor-predominant PD, including FD-PET scan results. As known genetic causes of autosomal dominant PD were excluded, this family harbors a novel genetic defect.

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BACKGROUND: Prominent visual symptoms can present in the visual variant of Alzheimer's disease (VVAD). Ophthalmologists have a significant role to play in the early diagnosis of VVAD. METHODS: We retrospectively reviewed the files of ten consecutive patients diagnosed with VVAD. All patients had a full neuro-ophthalmologic examination, a formal neurological and neuro-psychological testing, and cerebral MRI to confirm diagnosis. In addition, functional neuroimaging was obtained in seven patients. RESULTS: The common primary symptom at presentation with all patients was difficulty with near vision (reading difficulty n = 8, "visual blur" in near vision n = 2), and difficulty writing (n = 3). Following assessment, impaired reading and writing skills were evident in 9/10 and 8/10 patients respectively. Median distance visual acuity was 20/25 and at near the median visual acuity was J6. Partial homonymous visual field defect was detected in 80 % (8/10) of the patients. Color vision was impaired in all patients when tested with Ishihara pseudoisochromatic plates, but simple color naming was normal in 8/9 tested patients. Simultanagnosia was present in 8/10 patients. Vision dysfunction corresponded with cerebral MRI findings where parieto-occipital cortical atrophy was observed in all patients. PET scan (5 patients) or SPECT (2 patients) revealed parieto-occipital dysfunction (hypometabolism or hypoperfusion) in all 7 tested patients CONCLUSIONS: Visual difficulties are prominent in VVAD. Dyslexia, incomplete homonymous hemianopia, preserved color identification with abnormal color vision on Ishihara, and simultanagnosia were all symptoms observed frequently in this patient series. Ophthalmologists should be aware of the possibility of neurodegenerative disorders such as VVAD in patients with unexplained visual complaints, in particular reading difficulties.

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La consolidation est le processus qui transforme une nouvelle trace mnésique labile en ‎une autre plus stable et plus solide. Une des tâches utilisées en laboratoire pour ‎l’exploration de la consolidation motrice dans ses dimensions comportementale et ‎cérébrale est la tâche d’apprentissage de séquences motrices. Celle-ci consiste à ‎reproduire une même série de mouvements des doigts, apprise de manière implicite ou ‎explicite, tout en mesurant l’amélioration dans l’exécution. Les études récentes ont ‎montré que, dans le cas de l’apprentissage explicite de cette tâche, la consolidation de la ‎trace mnésique associée à cette nouvelle habileté dépendrait du sommeil, et plus ‎particulièrement des fuseaux en sommeil lent. Et bien que deux types de fuseaux aient ‎été décrits (lents et rapides), le rôle de chacun d’eux dans la consolidation d’une ‎séquence motrice est encore mal exploré. En effet, seule une étude s’est intéressée à ce ‎rôle, montrant alors une implication des fuseaux rapides dans ce processus mnésique ‎suite à une nuit artificiellement altérée. D’autre part, les études utilisant l’imagerie ‎fonctionnelle (IRMf et PET scan) menées par différentes équipes dont la notre, ont ‎montré des changements au niveau de l’activité du système cortico-striatal suite à la ‎consolidation motrice. Cependant, aucune corrélation n’a été faite à ce jour entre ces ‎changements et les caractéristiques des fuseaux du sommeil survenant au cours de la nuit ‎suivant un apprentissage moteur. Les objectifs de cette thèse étaient donc: 1) de ‎déterminer, à travers des enregistrements polysomnographiques et des analyses ‎corrélationnelles, les caractéristiques des deux types de fuseaux (i.e. lents et rapides) ‎associées à la consolidation d’une séquence motrice suite à une nuit de sommeil non ‎altérée, et 2) d’explorer, à travers des analyses corrélationnelles entre les données ‎polysomnographiques et le signal BOLD (« Blood Oxygenated Level Dependent »), ‎acquis à l’aide de l’imagerie par résonance magnétique fonctionnelle (IRMf), ‎l’association entre les fuseaux du sommeil et les activations cérébrales suite à la ‎consolidation de la séquence motrice. Les résultats de notre première étude ont montré ‎une implication des fuseaux rapides, et non des fuseaux lents, dans la consolidation ‎d’une séquence motrice apprise de manière explicite après une nuit de sommeil non ‎altérée, corroborant ainsi les résultats des études antérieures utilisant des nuits de ‎sommeil altérées. En effet, les analyses statistiques ont mis en évidence une ‎augmentation significative de la densité des fuseaux rapides durant la nuit suivant ‎l’apprentissage moteur par comparaison à la nuit contrôle. De plus, cette augmentation ‎corrélait avec les gains spontanés de performance suivant la nuit. Par ailleurs, les ‎résultats de notre seconde étude ont mis en évidence des corrélations significatives entre ‎l’amplitude des fuseaux de la nuit expérimentale d’une part et les gains spontanés de ‎performance ainsi que les changements du signal BOLD au niveau du système cortico-‎striatal d’autre part. Nos résultats suggèrent donc un lien fonctionnel entre les fuseaux ‎du sommeil, les gains de performance ainsi que les changements neuronaux au niveau ‎du système cortico-striatal liés à la consolidation d’une séquence motrice explicite. Par ‎ailleurs, ils supportent l’implication des fuseaux rapides dans ce type de consolidation ; ‎ceux-ci aideraient à l’activation des circuits neuronaux impliqués dans ce processus ‎mnésique et amélioreraient par la même occasion la consolidation motrice liée au ‎sommeil.‎

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The goal of this study was to investigate the specific patterns of memory breakdown in patients suffering from early-onset Alzheimer’s disease (EOAD) and late-onset Alzheimer’s disease (LOAD). Twenty EOAD patients, twenty LOAD patients, twenty matched younger controls, and twenty matched older controls participated in this study. All participants underwent a detailed neuropsychological assessment, an MRI scan, an FDG-PET scan, and AD patients had biomarkers as supporting evidence of both amyloïdopathy and neuronal injury. Results of the neuropsychological assessment showed that both EOAD and LOAD groups were impaired in the domains of memory, executive functions, language, praxis, and visuoconstructional abilities, when compared to their respective control groups. EOAD and LOAD groups, however, showed distinct patterns of memory impairment. Even though both groups were similarly affected on measures of episodic, short term and working memory, in contrast semantic memory was significantly more impaired in LOAD than in EOAD patients. The EOAD group was not more affected than the LOAD group in any memory domain. EOAD patients, however, showed significantly poorer performance in other cognitive domains including executive functions and visuoconstructional abilities. A more detailed analysis of the pattern of semantic memory performance among patient groups revealed that the LOAD was more profoundly impaired, in tasks of both spontaneous recall and semantic recognition. Voxel-Based Morphometry (VBM) analyses showed that impaired semantic performance in patients was associated with reduced gray matter volume in the anterior temporal lobe region, while PET-FDG analyses revealed that poorer semantic performance was associated with greater hypometabolism in the left temporoparietal region, both areas reflecting key regions of the semantic network. Results of this study indicate that EOAD and LOAD patients present with distinct patterns of memory impairment, and that a genuine semantic impairment may represent one of the clinical hallmarks of LOAD.

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Recent reports showed that early-interim PET-scan is the only tool predicting treatment outcome in advanced-stage classical Hodgkin lymphoma (asCHL). We evaluated the prognostic impact of a series of immunohistochemical markers, mentioned in literature as prognostic factors, on tissue microarrays assembled from biopsies of 220 patients: STAT1, SAP, TOP2A, PCNA and CD20, both in neoplastic (HRSC) and microenvironment cells (MC); RRM2, MAD2, CDC2, BCL2, P53, BCL11A and EBER in HRSC; ALDH1A1, TIA-1, granzyme B, perforin, FOXP3, and PD-1 in MC. All patients had been treated with standard ABVD ± Rx therapy. Interim-PET after 2 ABVD courses was evaluated according to the criteria indicated by Gallamini in his study (Journal of Clinical Oncology, 2007). The survival analysis has been performed in a subset of 138 patients whose complete clinical information were available: the mean age was 33.3 years (14-79), the stage III-IVB in 98 and IIB in 40, and the mean follow-up 38.1 months (7.6-71.9). Histopathology review showed: NS-I 75, NS-II 22, MC 20, DL 3, and CHL/nos 18 cases. Interim-PET was positive in 30 patients, while treatment failure was recorded in 32. In univariate analysis the factors related to treatment outcome were BCL2 on HRSC (cut-off value 50%), STAT1/SAP on MC, and PET (Log-rank 6.9, 7.9 and 93.9 respectively). The combined expression of STAT1 and SAP was scored in three levels depending on the architectural pattern: score 0 for expression of both with a diffuse/rosetting pattern; score 1 for discordant combination of diffuse/rosetting and scattered patterns; score 2 for both markers with a scattered pattern; the 3y-PFS were 87.4%, 69.9% and 61.9% respectively. In multivariate analysis PET, BCL2 and STAT1/SAP remained significant (HR: 24.8, 4.6, 7.5 and 5.6, respectively; p<.01). The proposed model is able to predict treatment response in AsCHL, even if with a lower efficacy than PET. However, unlike PET, it can be applied upfront therapy.

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We describe a 61-year-old patient with clinical evidence of limbic encephalitis who improved with anticonvulsant treatment only, that is, without the use of immunosuppressive agents. Three years following occurrence of anosmia, increasing memory deficits, and emotional disturbances, he presented with new-onset temporal lobe epilepsy, with antibodies binding to neuronal voltage-gated potassium channels and bitemporal hypometabolism on FDG-PET scan; the MRI scan was normal. This is most likely a case of spontaneous remission, illustrating that immunosuppressive therapy might be suspended in milder courses of limbic encephalitis. It remains open whether treatment with anticonvulsant drugs played an additional beneficiary role through the direct suppression of seizures or, additionally, through indirect immunomodulatory side effects.