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Papers by Jonathan Tabares

Alcoholism-clinical and Experimental Research, 2005

Background: Neuropeptide Y (NPY) is a major endogenous regulator of anxiety-related behaviors and... more Background: Neuropeptide Y (NPY) is a major endogenous regulator of anxiety-related behaviors and emotionality. Transgenic work with NPY and null-mutant mice have implicated NPY in the control of alcohol consumption, suggesting that genetic variation of the prepro-NPY gene may also contribute to the heritability of alcoholism. The aim of this study was to examine whether polymorphic variants of the NPY gene are associated with the diagnosis of alcohol dependence.

Breast Cancer Research, 2005

Randomised controlled trials have shown that the policy of mammographic screening confers a subst... more Randomised controlled trials have shown that the policy of mammographic screening confers a substantial and significant reduction in breast cancer mortality. This has often been accompanied, however, by an increase in breast cancer incidence, particularly during the early years of a screening programme, which has led to concerns about overdiagnosis, that is to say, the diagnosis of disease that, if left undetected and therefore untreated, would not become symptomatic. We used incidence data from two randomised controlled trials of mammographic screening, the Swedish Two-county Trial and the Gothenburg Trial, to establish the timing and magnitude of any excess incidence of invasive disease and ductal carcinoma in situ (DCIS) in the study groups, to ascertain whether the excess incidence of DCIS reported early in a screening trial is balanced by a later deficit in invasive disease and provide explicit estimates of the rate of 'real' and non-progressive 'overdiagnosed' tumours from the study groups of the trials. We used a multistate model for overdiagnosis and used Markov Chain Monte Carlo methods to estimate the parameters. After taking into account the effect of lead time, we estimated that less than 5% of cases diagnosed at prevalence screen and less than 1% of cases diagnosed at incidence screens are being overdiagnosed. Overall, we estimate overdiagnosis to be around 1% of all cases diagnosed in screened populations. These estimates are, however, subject to considerable uncertainty. Our results suggest that overdiagnosis in mammography screening is a minor phenomenon, but further studies with very large numbers are required for more precise estimation.

Cancer Journal, 2003

Advertisement. Close Window. Close Window. Thank you for choosing to subscribe to the eTOC for Th... more Advertisement. Close Window. Close Window. Thank you for choosing to subscribe to the eTOC for The Cancer Journal. Enter your Email address: Wolters Kluwer Health may email you for journal alerts and information, but is ...

Statistics in Medicine, 2003

The mean sojourn time (the duration of the period during which a cancer is symptom free but poten... more The mean sojourn time (the duration of the period during which a cancer is symptom free but potentially detectable by screening) and the screening sensitivity (the probability that a screen applied to a cancer in the preclinical screen detectable period will result in a positive diagnosis) are two important features of a cancer screening programme. Little data from any single study are available on the potential effectiveness of mammographic screening for breast cancer in women with a family history of the disease, despite this being an important public health issue. We develop a method of estimation, from two separate studies, of the two parameters, assuming that transition from no disease to preclinical screen detectable disease, and from preclinical disease to clinical disease, are Poisson processes. Estimation is performed by a Markov chain Monte Carlo algorithm. The method is applied to the synthesis of two studies of mammographic screening in women with a family history of breast cancer, one in Manchester and one in Kopparberg, Sweden. Copyright © 2003 John Wiley & Sons, Ltd.

Nutrition and Cancer-an International Journal, 2009

Objectives-To investigate patterns of food and nutrient consumption in Golestan province, a highi... more Objectives-To investigate patterns of food and nutrient consumption in Golestan province, a highincidence area for esophageal cancer (EC) in northern Iran.

Gender Place and Culture, 2010

Drawing upon postcolonial theorizing on diasporic positionalities and Homi Bhabha's theorization ... more Drawing upon postcolonial theorizing on diasporic positionalities and Homi Bhabha's theorization on ‘third space’ and hybridity, this study shows how young American Muslim women engage in their own interpretations of Islam based on their individual needs and situations. Individual in-depth interviews were conducted with 26 respondents in Ohio and Texas in order to gain insights into the identities of American Muslim women with immigrant backgrounds. Respondents emphasized their own ‘research’ on Islam as an important foundation of their faith. The narratives of the American Muslim women showed that they subverted and transgressed dominant meanings, while negotiating new ones through their everyday lived experiences. However, without indulging in an uncritical celebration of interstitial spaces, this study also strives to highlight the power relations implicit in the performances of complex, hybrid identities in the post-9/11 American context.Basándose en teorías postcoloniales sobre las posicionalidades diaspóricas y sobre las teorías de Homi Bhabha sobre el ‘tercer espacio’ e hibridez, este estudio muestra cómo jóvenes mujeres musulmanas estadounidenses hacen sus propias interpretaciones del Islam, basándose en sus necesidades y situaciones individuales. Se llevaron a cabo entrevistas individuales profundas con 26 personas en Ohio y Texas con el objetivo de comprender mejor las identidades de las mujeres musulmanas estadounidenses con antecedentes de inmigración. Las entrevistadas enfatizaron su propia ‘investigación’ sobre el Islam como un fundamento importante de su fe. Las narrativas de las estadounidenses musulmanas mostraron que subvertían y transgredían los significados dominantes, mientras negociaban otros nuevos a través de sus experiencias cotidianas. Sin embargo, sin ser indulgente con una celebración acrítica de los espacios intersticiales, este estudio también se esfuerza por remarcar las relaciones de poder implícitas en la representación de identidades complejas e híbridas en el contexto estadounidense del post 11 de septiembre.

Stereotactic and Functional Neurosurgery, 1999

Although the correspondence between functional-magnetic resonance imaging (fMRI) representations ... more Although the correspondence between functional-magnetic resonance imaging (fMRI) representations of the sensorimotor cortex and intraoperative electrophysiology (including somatosensory evoked potential, SSEP, recordings and direct cortical stimulation) has been reported, a similar correspondence between fMRI and intraoperative localization of the language-sensitive cortex is not as well established. The aim of the present study was to evaluate the concordance between fMRI and intraoperative electrophysiology with respect to the localization of the language-sensitive and sensorimotor cortices. We present the results of 21 patients who underwent language and sensorimotor mapping by fMRI and intraoperative electrophysiology including SSEP recordings (n = 21), direct cortical stimulation of motor cortex (n = 15) and direct cortical stimulation of Broca's and Wernicke's area (n = 5). When responses were obtained with both methods, localization of function concurred in all cases. These observations suggest that fMRI represents a reliable preoperative tool for the identification of language-sensitive areas.

The aim of this study was to review the prognostic significance of pathologic and radiologic fact... more The aim of this study was to review the prognostic significance of pathologic and radiologic factors for screening-detected invasive breast cancers of any size. The patient group was a consecutive series of 470 screening-detected invasive breast cancers that were diagnosed between 1988 and 1998. Data regarding tumor type, grade, maximum invasive diameter, lymph node status, and the presence or absence of vascular invasion were recorded, as were the mammographic features of the lesion. Survival was ascertained from hospital records and a cancer registry. Differences in survival were assessed using Kaplan-Meier survival curves with a log-rank test for difference. The significance of any correlations was assessed using the chi-square test and the chi-square test for trend. Multivariate analysis used a Cox proportional hazards model. At univariate analysis, large invasive size, the presence of definite vascular invasion, high histologic grade, and nodal involvement were associated with poorer breast-cancer-specific survival. Mammographic spiculation (the presence of either a spiculated mass or distortion) was associated with more prolonged breast-cancer-specific survival. The presence or absence of mammographic comedo calcification did not influence breast-cancer-specific survival. In a Cox multivariate analysis that included those factors significant in univariate analysis, size, grade, nodal stage, and mammographic spiculation maintained their prognostic significance. Mammographic spiculation is an independent, good prognostic factor for screening-detected invasive breast cancer. The mechanism of how mammographic spiculation confers a beneficial prognostic effect is not clear.