187 resultados para Shareholder Value


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Intraoperative ultrasound (IOUS) has been described to be useful during central corpectomy for compressive cervical myelopathy. This study aimed at documenting the utility of IOUS in oblique cervical corpectomy (OCC). Prospective data from 24 patients undergoing OCC for cervical spondylotic myelopathy and ossified posterior longitudinal ligament (OPLL) were collected. Patients had a preoperative cervical spine magnetic resonance (MR) image, IOUS and a postoperative cervical CT scan. Retrospective data from 16 historical controls that underwent OCC without IOUS were analysed to compare the incidence of residual compression between the two groups. IOUS identified the vertebral artery in all cases, detected residual cord compression in six (27%) and missed compression in two cases (9%). In another two cases with OPLL, IOUS was sub-optimal due to shadowing. IOUS measurement of the corpectomy width correlated well with these measurements on the postoperative CT. The extent of cord expansion noted on IOUS after decompression showed no correlation with immediate or 6-month postoperative neurological recovery. No significant difference in residual compression was noted in the retrospective and prospective groups of the study. Craniocaudal spinal cord motion was noted after the completion of the corpectomy. IOUS is an inexpensive and simple real-time imaging modality that may be used during OCC for cervical spondylotic myelopathy. It is helpful in identifying the vertebral artery and determining the trajectory of approach, however, it has limited utility in patients with OPLL due to artifacts from residual ossification.

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The aim of this study was to compare the diagnostic value of post-mortem computed tomography angiography (PMCTA) to conventional, ante-mortem computed tomography (CT)-scan, CT-angiography (CTA) and digital subtraction angiography (DSA) in the detection and localization of the source of bleeding in cases of acute hemorrhage with fatal outcomes. The medical records and imaging scans of nine individuals who underwent a conventional, ante-mortem CT-scan, CTA or DSA and later died in the hospital as a result of an acute hemorrhage were reviewed. Post-mortem computed tomography angiography, using multi-phase post-mortem CTA, as well as medico-legal autopsies were performed. Localization accuracy of the bleeding was assessed by comparing the diagnostic findings of the different techniques. The results revealed that data from ante-mortem and post-mortem radiological examinations were similar, though the PMCTA showed a higher sensitivity for detecting the hemorrhage source than did ante-mortem radiological investigations. By comparing the results of PMCTA and conventional autopsy, much higher sensitivity was noted in PMCTA in identifying the source of the bleeding. In fact, the vessels involved were identified in eight out of nine cases using PMCTA and only in three cases through conventional autopsy. Our study showed that PMCTA, similar to clinical radiological investigations, is able to precisely identify lesions of arterial and/or venous vessels and thus determine the source of bleeding in cases of acute hemorrhages with fatal outcomes.

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Introduction: la biopsie du ganglion sentinelle (GS) est une procédure reconnue et fiable pour établir le stade ganglionnaire du mélanome cutané. Le GS est le facteur pronostique le plus puissant pour la survie des patients atteints d'un mélanome à risque intermédiaire, cliniquement localisé. Celui-ci est métastatique dans environ 15-30% des cas. Lorsque le GS est positif, un curage de l'aire ganglionnaire concernée est généralement entrepris. Néanmoins, seuls 20-25% de ces patients présentent des ganglions non-sentinelles (GNS) métastatiques. Ces données suggèrent que le curage, et les risques opératoires qui y sont associés, n'est peut-être pas nécessaire chez le trois-quarts de ces patients. Un autre aspect est que l'impact sur la survie des curages basé sur le résultat du GS n'est pas clairement démontré. La nécessité de ce curage d'emblé est actuellement en cours d'évaluation par un protocole international (Multicenter Selective Lymphadenectomy Trial II : MSLT II). Plusieurs auteurs ont essayé de classifier la charge tumorale du GS afin d'évaluer s'il était possible d'épargner le curage à certains patients et de mieux affiner ce facteur pronostic sans succès. En 2009, le Groupe Mélanome de l'EORTC (European Organisation for Research and Treatment of Cancer) a recommandé un protocole d'évaluation anatomopathologique du GS-positif en trois items: (1) la localisation micro-anatomique des métastases à l'intérieur du ganglion selon Dewar (A = sous-capsulaire, B = combinée sous-capsulaire and parenchymateuse, C = parenchymateuse, D = multifocale, and'E = extensive) ; (2) la mesure de la taille tumorale dans le ganglion selon les critères de Rotterdam pour le diamètre maximal. Le diamètre de la plus grande métastase est exprimé en nombre absolu et (3) la taille tumorale stratifiée par catégories : <0.1mm, 0.1-1.0mm et >1.0 mm. Le but de cette étude rétrospective d'une cohorte de patients, était d'investiguer les résultats des GS-positifs et d'analyser les facteurs pronostiques de la survie à la lumière des recommandations de l'EORTC. Ainsi que de comparer les sous-groupes du GS-positif avec une invasion minimale (taille tumorale <0.1mm et/ou atteinte sous-capsulaire) avec le GS-négatif. Les facteurs pouvant prédire la présence de GNS- positif ont également été analysés. Matériel et méthode : une étude des dossiers a été réalisée pour les 499 patients consécutifs entre 1997 et 2008 qui ont eu une biopsie du GS dans notre institution. Le dégrée d'envahissement du GS-positif a été entièrement revue par l'équipe référente de l'Institut de Pathologie (Dresse E. Saiji et Dresse H. Bouzourène) selon les recommandations de l'EORTC. Des analyses univariées et multivariées des potentiels facteuis pronostics ont été réalisées. Des analyses de survie ont également été effectuées avec des courbes d'estimation de Kaplan-Meier combinées à une régression de Cox. Le protocole a été accepté par la Commission d'Ethique. Résultats: un GS-positif a été trouvé chez 123 (25%) patients panni les 499 qui ont bénéficié d'une biopsie. Avec un suivi médian de 52 mois, la survie à 5 ans sans récidive (SSR), spécifique à la maladie (SS) et globale (SG) étaient de 88%, 94%, et 90% respectivement pour les patients avec GS-négatif. Concernant les GS avec invasion minimale, 21 patients étaient dans le sous-groupe <0.1 mm selon les critères de Rotterdam et 52 patients dans le sous-groupe sous-capsulaire selon Dewar. La survie dans ces deux sous-groupes était de 80% et 57% pour la SSR, 87% et 70% pour la SS, 87% et 68% pour la SG, respectivement. L'analyse multivariée des GS-positifs a montré que les facteuis suivants influençaient significativement la survie (SSR, SS et SG): l'épaisseur selon Breslow de la tumeur primaire (p=0.002, 0.006, 0.004), la taille tumorale du GS-positif >0.1 mm (p= 0.01, 0.04, 0.03), le genre masculin (p=0.06, 0.005, 0.002) et l'ulcération de la tumeur primaire (p=0.05, 0.03, 0.007). L'analyse des sous-groupes avec invasion minimale n'a pas permis d'établir de facteur pour prédire la négativité des GNSs. Conclusion: La classification du GS-positif par la taille tumorale selon les critères de Rotterdam est un facteur pronostique simple et utile pour évaluer la survie des patients atteints de mélanome. Nous avons observé une tendance (non statistiquement significative) d'une survie diminuée pour le sous-groupe des patients avec GS-positif et une taille de la métastase <0.1 mm comparée à celle des patients avec GS-négatif. Ceci nous incite à conclure que ce sous-groupe de patients ne devrait pas être assimilé et traité comme ceux qui ont un GS-négatif. D'autre part nos résultats montrent que la localisation micro-anatomique selon Dewar n'est pas un outil pronostique utile pour évaluer la survie, ni pour prédire le status des GNSs.

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PURPOSE: To evaluate the prognostic and predictive value of Ki-67 labeling index (LI) in a trial comparing letrozole (Let) with tamoxifen (Tam) as adjuvant therapy in postmenopausal women with early breast cancer. PATIENTS AND METHODS: Breast International Group (BIG) trial 1-98 randomly assigned 8,010 patients to four treatment arms comparing Let and Tam with sequences of each agent. Of 4,922 patients randomly assigned to receive 5 years of monotherapy with either agent, 2,685 had primary tumor material available for central pathology assessment of Ki-67 LI by immunohistochemistry and had tumors confirmed to express estrogen receptors after central review. The prognostic and predictive value of centrally measured Ki-67 LI on disease-free survival (DFS) were assessed among these patients using proportional hazards modeling, with Ki-67 LI values dichotomized at the median value of 11%. RESULTS: Higher values of Ki-67 LI were associated with adverse prognostic factors and with worse DFS (hazard ratio [HR; high:low] = 1.8; 95% CI, 1.4 to 2.3). The magnitude of the treatment benefit for Let versus Tam was greater among patients with high tumor Ki-67 LI (HR [Let:Tam] = 0.53; 95% CI, 0.39 to 0.72) than among patients with low tumor Ki-67 LI (HR [Let:Tam] = 0.81; 95% CI, 0.57 to 1.15; interaction P = .09). CONCLUSION: Ki-67 LI is confirmed as a prognostic factor in this study. High Ki-67 LI levels may identify a patient group that particularly benefits from initial Let adjuvant therapy.

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Do our brains implicitly track the energetic content of the foods we see? Using electrical neuroimaging of visual evoked potentials (VEPs) we show that the human brain can rapidly discern food's energetic value, vis à vis its fat content, solely from its visual presentation. Responses to images of high-energy and low-energy food differed over two distinct time periods. The first period, starting at approximately 165 ms post-stimulus onset, followed from modulations in VEP topography and by extension in the configuration of the underlying brain network. Statistical comparison of source estimations identified differences distributed across a wide network including both posterior occipital regions and temporo-parietal cortices typically associated with object processing, and also inferior frontal cortices typically associated with decision-making. During a successive processing stage (starting at approximately 300 ms), responses differed both topographically and in terms of strength, with source estimations differing predominantly within prefrontal cortical regions implicated in reward assessment and decision-making. These effects occur orthogonally to the task that is actually being performed and suggest that reward properties such as a food's energetic content are treated rapidly and in parallel by a distributed network of brain regions involved in object categorization, reward assessment, and decision-making.

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Background: Visual analog scales (VAS) are used to assess readiness to changeconstructs, which are often considered critical for change.Objective: We studied whether 3 constructs -readiness to change, importance of changing and confidence inability to change- predict risk status 6 months later in 20 year-old men with either orboth of two behaviors: risky drinking and smoking. Methods: 577 participants in abrief intervention randomized trial were assessed at baseline and 6 months later onalcohol and tobacco consumption and with three 1-10 VAS (readiness, importance,confidence) for each behavior. For each behavior, we used one regression model foreach constructs. Models controlled for receipt of a brief intervention and used thelowest level (1-4) in each construct as the reference group (vs medium (5-7) and high(8-10) levels).Results: Among the 475 risky drinkers, mean (SD) readiness, importance and confidence to change drinking were 4.0 (3.1), 2.8 (2.2) and 7.2 (3.0).Readiness was not associated with being alcohol-risk free 6 months later (OR 1.3[0.7; 2.2] and 1.4 [0.8; 2.6] for medium and high readiness). High importance andhigh confidence were associated with being risk free (OR 0.9 [0.5; 1.8] and 2.9 [1.2;7.5] for medium and high importance; 2.1 [1.0;4.8] and 2.8 [1.5;5.6] for medium andhigh confidence). Among the 320 smokers, mean readiness, importance andconfidence to change smoking were 4.6 (2.6), 5.3 (2.6) and 5.9 (2.6). Neitherreadiness nor importance were associated with being smoking free (OR 2.1 [0.9; 4.7]and 2.1 [0.8; 5.8] for medium and high readiness; 1.4 [0.6; 3.4] and 2.1 [0.8; 5.4] formedium and high importance). High confidence was associated with being smokingfree (OR 2.2 [0.8;6.6] and 3.4 [1.2;9.8] for medium and high confidence).Conclusions: For drinking and smoking, high confidence in ability to change wasassociated -with similar magnitude- with a favorable outcome. This points to thevalue of confidence as an important predictor of successful change.

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The prognostic significance of magnetic resonance imaging (MRI) in the neonatal period was studied prospectively in 43 term infants with perinatal asphyxia. MRI was performed between 1 and 14 days after birth with a high field system (2.35 Tesla). Neurodevelopmental outcome was assessed by a standardized neurological examination and the Griffiths developmental test at a mean age of 18.9 months. The predictive value of the various MRI patterns was as follows: Severe diffuse brain injury (pattern AII+III; n = 7) and lesions of thalamus and basal ganglia (pattern C; n = 5) were strongly associated with poor outcome and greatly reduced head growth. Mild diffuse brain injury (pattern AI; n = 7), parasagittal lesions (B; n = 7), periventricular hyperintensity (D; n = 2), focal brain necrosis and hemorrhage (E; n = 3) and periventricular hypointense stripes (on T2-weighted images; F; n = 3) led in one third of the infants to minor neurological disturbances and mild developmental delay. Infants with normal MRI findings (G; n = 9) developed normally with the exception of one infant who was mildly delayed at 18 months. The results indicate that MRI examination during the first two weeks of life is of prognostic significance in term infants suffering from perinatal asphyxia. Severe hypoxic-ischemic brain lesions were associated highly significantly with poor neuro-developmental outcome, whereas infants with inconspicuous MRI developed normally.

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The O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation status is a predictive parameter for the response of malignant gliomas to alkylating agents such as temozolomide. First clinical trials with temozolomide plus bevacizumab therapy in metastatic melanoma patients are ongoing, although the predictive value of the MGMT promoter methylation status in this setting remains unclear. We assessed MGMT promoter methylation in formalin-fixed, primary tumor tissue of metastatic melanoma patients treated with first-line temozolomide and bevacizumab from the trial SAKK 50/07 by methylation-specific polymerase chain reaction. In addition, the MGMT expression levels were also analyzed by MGMT immunohistochemistry. Eleven of 42 primary melanomas (26%) revealed a methylated MGMT promoter. Promoter methylation was significantly associated with response rates CR + PR versus SD + PD according to RECIST (response evaluation criteria in solid tumors) (p<0.05) with a trend to prolonged median progression-free survival (8.1 versus 3.4 months, p>0.05). Immunohistochemically different protein expression patterns with heterogeneous and homogeneous nuclear MGMT expression were identified. Negative MGMT expression levels were associated with overall disease stabilization CR + PR + SD versus PD (p=0.05). There was only a poor correlation between MGMT methylation and lack of MGMT expression. A significant proportion of melanomas have a methylated MGMT promoter. The MGMT promoter methylation status may be a promising predictive marker for temozolomide therapy in metastatic melanoma patients. Larger sample sizes may help to validate significant differences in survival type endpoints.

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Forensic scientists face increasingly complex inference problems for evaluating likelihood ratios (LRs) for an appropriate pair of propositions. Up to now, scientists and statisticians have derived LR formulae using an algebraic approach. However, this approach reaches its limits when addressing cases with an increasing number of variables and dependence relationships between these variables. In this study, we suggest using a graphical approach, based on the construction of Bayesian networks (BNs). We first construct a BN that captures the problem, and then deduce the expression for calculating the LR from this model to compare it with existing LR formulae. We illustrate this idea by applying it to the evaluation of an activity level LR in the context of the two-trace transfer problem. Our approach allows us to relax assumptions made in previous LR developments, produce a new LR formula for the two-trace transfer problem and generalize this scenario to n traces.

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Status signals function in a number of species to communicate competitive ability to conspecific rivals during competition for resources. In the paper wasp Polistes dominulus, variable black clypeal patterns are thought to be important in mediating competition among females. Results of previous behavioral experiments in the lab indicate that P dominulus clypeal patterns provide information about an individual's competitive ability to rivals during agonistic interactions. To date, however, there has been no detailed examination of the adaptive value of clypeal patterns in the wild. To address this, we looked for correlations between clypeal patterning and various fitness measures, including reproductive success, hierarchical rank, and survival, in a large, free-living population of P. dominulus in southern Spain. Reproductive success over the nesting season was not correlated with clypeal patterning. Furthermore, there was no relationship between a female's clypeal patterning and the rank she achieved within the hierarchy or her survival during nest founding. Overall, we found no evidence that P dominulus clypeal patterns are related to competitive ability or other aspects of quality in our population. This result is consistent with geographical variation in the adaptive value of clypeal patterns between P. dominulus populations; however, data on the relationship between patterning and fitness from other populations are required to test this hypothesis.