530 research outputs found
Brain mapping in cognitive disorders: a multidisciplinary approach to learning the tools and applications of functional neuroimaging
<p>Abstract</p> <p>Background</p> <p>With rapid advances in functional imaging methods, human studies that feature functional neuroimaging techniques are increasing exponentially and have opened a vast arena of new possibilities for understanding brain function and improving the care of patients with cognitive disorders in the clinical setting. There is a growing need for medical centers to offer clinically relevant functional neuroimaging courses that emphasize the multifaceted and multidisciplinary nature of this field. In this paper, we describe the implementation of a functional neuroimaging course focusing on cognitive disorders that might serve as a model for other medical centers. We identify key components of an active learning course design that impact student learning gains in methods and issues pertaining to functional neuroimaging that deserve consideration when optimizing the medical neuroimaging curriculum.</p> <p>Methods</p> <p>Learning gains associated with the course were assessed using polychoric correlation analysis of responses to the SALG (Student Assessment of Learning Gains) instrument.</p> <p>Results</p> <p>Student gains in the functional neuroimaging of cognition as assessed by the SALG instrument were strongly associated with several aspects of the course design.</p> <p>Conclusion</p> <p>Our implementation of a multidisciplinary and active learning functional neuroimaging course produced positive learning outcomes. Inquiry-based learning activities and an online learning environment contributed positively to reported gains. This functional neuroimaging course design may serve as a useful model for other medical centers.</p
Predictors of latent tuberculosis treatment initiation and completion at a U.S. public health clinic: a prospective cohort study
Background Treatment of latent tuberculosis infection (LTBI) is a key component in U.S. tuberculosis control, assisted by recent improvements in LTBI diagnostics and therapeutic regimens. Effectiveness of LTBI therapy, however, is limited by patientsâ willingness to both initiate and complete treatment. We aimed to evaluate the demographic, medical, behavioral, attitude-based, and geographic factors associated with LTBI treatment initiation and completion of persons presenting with LTBI to a public health tuberculosis clinic. Methods Data for this prospective cohort study were collected from structured patient interviews, self-administered questionnaires, clinic intake forms, and U.S. census data. All adults (>17âyears) who met CDC guidelines for LTBI treatment between January 11, 2008 and May 6, 2009 at Wake County Health and Human Services Tuberculosis Clinic in Raleigh, North Carolina were included in the study. In addition to traditional social and behavioral factors, a three-level medical risk variable (low, moderate, high), based on risk factors for both progression to and transmission of active tuberculosis, was included for analysis. Clinic distance and neighborhood poverty level, based on percent residents living below poverty level in a personâs zip code, were also analyzed. Variables with a significance level <0.10 by univariate analysis were included in log binomial models with backward elimination. Models were used to estimate risk ratios for two primary outcomes: (1) LTBI therapy initiation (picking up one monthâs medication) and (2) therapy completion (picking up nine months INH therapy or four months rifampin monthly). Results 496 persons completed medical interviews and questionnaires addressing social factors and attitudes toward LTBI treatment. 26% persons initiated LTBI therapy and 53% of those initiating completed therapy. Treatment initiation predictors included: a non-employment reason for screening (RR 1.6, 95% CI 1.0-2.5), close contact to an infectious TB case (RR 2.5, 95% CI 1.8-3.6), regular primary care(RR 1.4, 95% CI 1.0-2.0), and history of incarceration (RR 1.7, 95% CI 1.0-2.8). Persons in the âhighâ risk category for progression/transmission of TB disease had higher likelihood of treatment initiation (pâ<â0.01), but not completion, than those with lower risk. Conclusions Investment in social support and access to regular primary care may lead to increased LTBI therapy adherence in high-risk populations
Non-standard interactions versus non-unitary lepton flavor mixing at a neutrino factory
The impact of heavy mediators on neutrino oscillations is typically described
by non-standard four-fermion interactions (NSIs) or non-unitarity (NU). We
focus on leptonic dimension-six effective operators which do not produce
charged lepton flavor violation. These operators lead to particular
correlations among neutrino production, propagation, and detection non-standard
effects. We point out that these NSIs and NU phenomenologically lead, in fact,
to very similar effects for a neutrino factory, for completely different
fundamental reasons. We discuss how the parameters and probabilities are
related in this case, and compare the sensitivities. We demonstrate that the
NSIs and NU can, in principle, be distinguished for large enough effects at the
example of non-standard effects in the --sector, which basically
corresponds to differentiating between scalars and fermions as heavy mediators
as leading order effect. However, we find that a near detector at superbeams
could provide very synergistic information, since the correlation between
source and matter NSIs is broken for hadronic neutrino production, while NU is
a fundamental effect present at any experiment.Comment: 32 pages, 5 figures. Final version published in JHEP. v3: Typo in Eq.
(27) correcte
Feasibility and willingness-to-pay for integrated community-based tuberculosis testing
BACKGROUND: Community-based screening for TB, combined with HIV and syphilis testing, faces a number of barriers. One significant barrier is the value that target communities place on such screening. METHODS: Integrated testing for TB, HIV, and syphilis was performed in neighborhoods identified using geographic information systems-based disease mapping. TB testing included skin testing and interferon gamma release assays. Subjects completed a survey describing disease risk factors, healthcare access, healthcare utilization, and willingness to pay for integrated testing. RESULTS: Behavioral and social risk factors among the 113 subjects were prevalent (71% prior incarceration, 27% prior or current crack cocaine use, 35% homelessness), and only 38% had a regular healthcare provider. The initial 24 subjects reported that they would be willing to pay a median 10 (IQR: 0-100) for TB testing when the question was asked in an open-ended fashion, but when the question was changed to a multiple-choice format, the next 89 subjects reported that they would pay a median 5 to get tested for TB, HIV, or syphilis. Among persons who received tuberculin skin testing, only 14/78 (18%) participants returned to have their skin tests read. Only 14/109 (13%) persons who underwent HIV testing returned to receive their HIV results. CONCLUSION: The relatively high-risk persons screened in this community outreach study placed low value on testing. Reported willingness to pay for such testing, while low, likely overestimated the true willingness to pay. Successful TB, HIV, and syphilis integrated testing programs in high risk populations will likely require one-visit diagnostic testing and incentives
Regional differentiation of felid vertebral column evolution: a study of 3D shape trajectories
Recent advances in geometric morphometrics provide improved techniques for extraction of biological information from shape and have greatly contributed to the study of ecomorphology and morphological evolution. However, the vertebral column remains an under-studied structure due in part to a concentration on skull and limb research, but most importantly because of the difficulties in analysing the shape of a structure composed of multiple articulating discrete units (i.e. vertebrae). Here, we have applied a variety of geometric morphometric analyses to three-dimensional landmarks collected on 19 presacral vertebrae to investigate the influence of potential ecological and functional drivers, such as size, locomotion and prey size specialisation, on regional morphology of the vertebral column in the mammalian family Felidae. In particular, we have here provided a novel application of a methodâphenotypic trajectory analysis (PTA)âthat allows for shape analysis of a contiguous sequence of vertebrae as functionally linked osteological structures. Our results showed that ecological factors influence the shape of the vertebral column heterogeneously and that distinct vertebral sections may be under different selection pressures. While anterior presacral vertebrae may either have evolved under stronger phylogenetic constraints or are ecologically conservative, posterior presacral vertebrae, specifically in the post-T10 region, show significant differentiation among ecomorphs. Additionally, our PTA results demonstrated that functional vertebral regions differ among felid ecomorphs mainly in the relative covariation of vertebral shape variables (i.e. direction of trajectories, rather than in trajectory size) and, therefore, that ecological divergence among felid species is reflected by morphological changes in vertebral column shape
Mena deficiency delays tumor progression and decreases metastasis in polyoma middle-T transgenic mouse mammary tumors
Introduction
The actin binding protein Mammalian enabled (Mena), has been implicated in the metastatic progression of solid tumors in humans. Mena expression level in primary tumors is correlated with metastasis in breast, cervical, colorectal and pancreatic cancers. Cells expressing high Mena levels are part of the tumor microenvironment for metastasis (TMEM), an anatomical structure that is predictive for risk of breast cancer metastasis. Previously we have shown that forced expression of Mena adenocarcinoma cells enhances invasion and metastasis in xenograft mice. Whether Mena is required for tumor progression is still unknown. Here we report the effects of Mena deficiency on tumor progression, metastasis and on normal mammary gland development. Methods
To investigate the role of Mena in tumor progression and metastasis, Mena deficient mice were intercrossed with mice carrying a transgene expressing the polyoma middle T oncoprotein, driven by the mouse mammary tumor virus. The progeny were investigated for the effects of Mena deficiency on tumor progression via staging of primary mammary tumors and by evaluation of morbidity. Stages of metastatic progression were investigated using an in vivo invasion assay, intravital multiphoton microscopy, circulating tumor cell burden, and lung metastases. Mammary gland development was studied in whole mount mammary glands of wild type and Mena deficient mice. Results
Mena deficiency decreased morbidity and metastatic dissemination. Loss of Mena increased mammary tumor latency but had no affect on mammary tumor burden or histologic progression to carcinoma. Elimination of Mena also significantly decreased epidermal growth factor (EGF) induced in vivo invasion, in vivo motility, intravasation and metastasis. Non-tumor bearing mice deficient for Mena also showed defects in mammary gland terminal end bud formation and branching. Conclusions
Deficiency of Mena decreases metastasis by slowing tumor progression and reducing tumor cell invasion and intravasation. Mena deficiency during development causes defects in invasive processes involved in mammary gland development. These findings suggest that functional intervention targeting Mena in breast cancer patients may provide a valuable treatment option to delay tumor progression and decrease invasion and metastatic spread leading to an improved prognostic outcome.National Cancer Institute (U.S.). Integrative Cancer Biology Program (grant U54 CA112967)Virginia and D.K. Ludwig Fund for Cancer Researc
A basal lithostrotian titanosaur (Dinosauria: Sauropoda) with a complete skull: Implications for the evolution and paleobiology of titanosauria
We describe Sarmientosaurus musacchioi gen. et sp. nov., a titanosaurian sauropod dinosaur from the Upper Cretaceous (Cenomanian - Turonian) Lower Member of the Bajo Barreal Formation of southern Chubut Province in central Patagonia, Argentina. The holotypic and only known specimen consists of an articulated, virtually complete skull and part of the cranial and middle cervical series. Sarmientosaurus exhibits the following distinctive features that we interpret as autapomorphies: (1) maximum diameter of orbit nearly 40% rostrocaudal length of cranium; (2) complex maxilla - lacrimal articulation, in which the lacrimal clasps the ascending ramus of the maxilla; (3) medial edge of caudal sector of maxillary ascending ramus bordering bony nasal aperture with low but distinct ridge; (4) ÂŽtongue-likeÂŽ ventral process of quadratojugal that overlaps quadrate caudally; (5) separate foramina for all three branches of the trigeminal nerve; (6) absence of median venous canal connecting infundibular region to ventral part of brainstem; (7) subvertical premaxillary, procumbent maxillary, and recumbent dentary teeth; (8) cervical vertebrae with ÂŽstrut-likeÂŽ centroprezygapophyseal laminae; (9) extremely elongate and slender ossified tendon positioned ventrolateral to cervical vertebrae and ribs. The cranial endocast of Sarmientosaurus preserves some of the most complete information obtained to date regarding the brain and sensory systems of sauropods. Phylogenetic analysis recovers the new taxon as a basal member of Lithostrotia, as the most plesiomorphic titanosaurian to be preserved with a complete skull. Sarmientosaurus provides a wealth of new cranial evidence that reaffirms the close relationship of titanosaurs to Brachiosauridae. Moreover, the presence of the relatively derived lithostrotian Tapuiasaurus in Aptian deposits indicates that the new Patagonian genus represents a ÂŽghost lineageÂŽ with a comparatively plesiomorphic craniodental form, the evolutionary history of which is missing for at least 13 million years of the Cretaceous. The skull anatomy of Sarmientosaurus suggests that multiple titanosaurian species with dissimilar cranial structures coexisted in the early Late Cretaceous of southern South America. Furthermore, the new taxon possesses a number of distinctive morphologies - such as the ossified cervical tendon, extremely pneumatized cervical vertebrae, and a habitually downward- facing snout - that have rarely, if ever, been documented in other titanosaurs, thus broadening our understanding of the anatomical diversity of this remarkable sauropod clade. The latter two features were convergently acquired by at least one penecontemporaneous diplodocoid, and may represent mutual specializations for consuming low-growing vegetation.Fil: MartĂnez, RubĂ©n DarĂo. Universidad Nacional de la Patagonia; ArgentinaFil: Lamanna, Matthew C.. Carnegie Museum Of Natural History; Estados UnidosFil: Novas, Fernando Emilio. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Oficina de CoordinaciĂłn Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "bernardino Rivadavia"; ArgentinaFil: Ridgely, Ryan C.. Ohio University College Of Osteopathic Medicine; Estados UnidosFil: Casal, Gabriel. Universidad Nacional de la Patagonia; ArgentinaFil: MartĂnez, Javier E.. Hospital Regional de Comodoro Rivadavia; ArgentinaFil: Vita, Javier R.. Resonancia MagnĂ©tica Borelli; ArgentinaFil: Witmer, Lawrence M.. Ohio University College Of Osteopathic Medicine; Estados Unido
Genome-Wide Linkage in a Highly Consanguineous Pedigree Reveals Two Novel Loci on Chromosome 7 for Non-Syndromic Familial Premature Ovarian Failure
BACKGROUND: The human condition known as Premature Ovarian Failure (POF) is characterized by loss of ovarian function before the age of 40. A majority of POF cases are sporadic, but 10-15% are familial, suggesting a genetic origin of the disease. Although several causal mutations have been identified, the etiology of POF is still unknown for about 90% of the patients.ŠMETHODOLOGY/PRINCIPAL FINDINGS: We report a genome-wide linkage and homozygosity analysis in one large consanguineous Middle-Eastern POF-affected family presenting an autosomal recessive pattern of inheritance. We identified two regions with a LOD(max) of 3.26 on chromosome 7p21.1-15.3 and 7q21.3-22.2, which are supported as candidate regions by homozygosity mapping. Sequencing of the coding exons and known regulatory sequences of three candidate genes (DLX5, DLX6 and DSS1) included within the largest region did not reveal any causal mutations.ŠCONCLUSIONS/SIGNIFICANCE: We detect two novel POF-associated loci on human chromosome 7, opening the way to the identification of new genes involved in the control of ovarian development and function
Varespladib and cardiovascular events in patients with an acute coronary syndrome: the VISTA-16 randomized clinical trial
IMPORTANCE: Secretory phospholipase A2(sPLA2) generates bioactive phospholipid products implicated in atherosclerosis. The sPLA2inhibitor varespladib has favorable effects on lipid and inflammatory markers; however, its effect on cardiovascular outcomes is unknown. OBJECTIVE: To determine the effects of sPLA2inhibition with varespladib on cardiovascular outcomes. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, randomized, multicenter trial at 362 academic and community hospitals in Europe, Australia, New Zealand, India, and North America of 5145 patients randomized within 96 hours of presentation of an acute coronary syndrome (ACS) to either varespladib (n = 2572) or placebo (n = 2573) with enrollment between June 1, 2010, and March 7, 2012 (study termination on March 9, 2012). INTERVENTIONS: Participants were randomized to receive varespladib (500 mg) or placebo daily for 16 weeks, in addition to atorvastatin and other established therapies. MAIN OUTCOMES AND MEASURES: The primary efficacy measurewas a composite of cardiovascular mortality, nonfatal myocardial infarction (MI), nonfatal stroke, or unstable angina with evidence of ischemia requiring hospitalization at 16 weeks. Six-month survival status was also evaluated. RESULTS: At a prespecified interim analysis, including 212 primary end point events, the independent data and safety monitoring board recommended termination of the trial for futility and possible harm. The primary end point occurred in 136 patients (6.1%) treated with varespladib compared with 109 patients (5.1%) treated with placebo (hazard ratio [HR], 1.25; 95%CI, 0.97-1.61; log-rank P = .08). Varespladib was associated with a greater risk of MI (78 [3.4%] vs 47 [2.2%]; HR, 1.66; 95%CI, 1.16-2.39; log-rank P = .005). The composite secondary end point of cardiovascular mortality, MI, and stroke was observed in 107 patients (4.6%) in the varespladib group and 79 patients (3.8%) in the placebo group (HR, 1.36; 95% CI, 1.02-1.82; P = .04). CONCLUSIONS AND RELEVANCE: In patients with recent ACS, varespladib did not reduce the risk of recurrent cardiovascular events and significantly increased the risk of MI. The sPLA2inhibition with varespladib may be harmful and is not a useful strategy to reduce adverse cardiovascular outcomes after ACS. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01130246. Copyright 2014 American Medical Association. All rights reserved
Open data and digital morphology
Over the past two decades, the development of methods for visualizing and analysing specimens digitally, in three and even four dimensions, has transformed the study of living and fossil organisms. However, the initial promise, that the widespread application of such methods would facilitate access to the underlying digital data, has not been fully achieved. The underlying datasets for many published studies are not readily or freely available, introducing a barrier to verification and reproducibility, and the reuse of data. There is no current agreement or policy on the amount and type of data that should be made available alongside studies that use, and in some cases are wholly reliant on, digital morphology. Here, we propose a set of recommendations for minimum standards and additional best practice for 3D digital data publication, and review the issues around data storage, management and accessibility
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