519 research outputs found

    Test‐retest reliability of amygdala response to emotional faces

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    In the current study, we evaluated the test‐retest reliability of amygdala response using an emotional face‐matching task that has been widely used to examine pathophysiology and treatment mechanisms in psychiatric populations. Activation within the fusiform face area ( FFA ) was also examined. Twenty‐seven healthy volunteers completed a variation of the face‐matching paradigm developed by Hariri et al. (2000) at two time points approximately 90 days apart. Estimates of test‐retest reliability of amygdala response to fearful faces were moderate, whereas angry and happy faces showed poor reliability. Test‐retest reliability of the FFA was moderate to strong, regardless of facial affect. Collectively, these findings indicate that the reliability of the BOLD MR signal in the amygdala varies substantially by facial affect. Efforts to improve measurement precision, enlarge sample sizes, or increase the number of assessment occasions seem warranted.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/100342/1/psyp12129.pd

    Reward dysfunction in major depression: Multimodal neuroimaging evidence for refining the melancholic phenotype

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    Reward dysfunction is thought to play a core role in the pathophysiology of major depressive disorder (MDD). Event-related potential (ERP) and functional magnetic resonance imaging (fMRI) studies have identified reward processing deficits in MDD, but these methods have yet to be applied together in a single MDD sample. We utilized multimodal neuroimaging evidence to examine reward dysfunction in MDD. Further, we explored how neurobiological reward dysfunction would map onto subtypes of MDD. The feedback negativity (FN), an ERP index of reward evaluation, was recorded in 34 unmedicated depressed individuals and 42 never-depressed controls during a laboratory gambling task. Ventral striatal (VS) activation to reward was recorded in a separate fMRI session, using an identical task, among a subgroup of 24 depressed individuals and a comparison group of 18 non-depressed controls. FN amplitude was blunted in MDD. This effect was driven by a MDD subgroup characterized by impaired mood reactivity to positive events, a core feature of melancholic MDD. A similar pattern was observed for VS activation, which was also blunted among the MDD subgroup with impaired mood reactivity. Neither FN amplitude nor VS activation were related to the full, DSM-defined melancholic or atypical MDD subtypes. Across the MDD sample, FN amplitude and VS activation were correlated, indicating convergence across methods. These results indicate that not all MDD is characterized by reward dysfunction, and that there is meaningful heterogeneity in reward processing within MDD. The current study offers neurobiological evidence that impaired mood reactivity is a key phenotypic distinction for subtyping MDD, and further suggests that the existing melancholic phenotype may require further refinement

    Treatment of breast cancer: Imo State Nigeria versus Indiana, USA women -- comparative analytic study

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    BACKGROUND: Women with breast cancer undergo multimodal treatment for best outcome. This study seeks to identify the treatment challenges for such women in Imo State, Nigeria vis-Ă -vis similar women in Indiana USA. We compared the treatment modalities of both groups; noting predictors of compliance for subsequent action. SETTING: Federal Medical Centre, Owerri; Imo State, Imo State University, Orlu, Nigeria and Indiana University Hospital, Indiana, USA. DESIGN: A retrospective study. METHODOLOGY: From 2000-2013, 100 randomly pulled charts of patients treated for pathologically confirmed breast cancer in Imo, Nigeria Federal Medical Centre Owerri, Imo State University Hospital; and Indiana University Hospital U.S. respectively were reviewed. The demographics, clinical and pathological data of the patients with confirmed breast cancer were obtained. The data were formatted and analyzed with SPSS version 16.0. The clinical features, management options, outcomes and specific features were compared for both groups using Wilcoxon Rank Sum tests (age, parity) and chi-square tests for all other variables. A 5% significance level was used for all tests. RESULTS: One hundred patients were included for each group. The mean/minimum ages; Imo, Nigeria 41.7/21 (SD/SE 15.3/1.5) vs. Indiana, U.S.56.4/29 (SD 12.4/SE 1.2) p<0.0001. Histology for Indiana USA women was predominantly ductal carcinoma in situ (DCIS) P<0.0001 while that of Imo, Nigeria was invasive ductal carcinoma inflammatory cancer P<0.0326. Women in both locations received chemotherapy and surgery. Imo women received less radiotherapy. Toxicity from chemotherapy remained constant features for both groups, P<0.0001. In Indiana USA, the 5year survival exceeded 85%; In Imo Nigeria it was 10%. This study showed that Women on both locations who were likely to be compliant were those receiving mastectomy; Imo, Nigeria 44(56%) <0.013 vs. Indiana, U.S. 74(80%) p<0.0186; women with cosmesis given; Imo, Nigeria 41(42%) vs. Indiana, U.S. 91 (94%) p<0.0001. Sample sizes were inadequate to perform multivariable models. CONCLUSION: The multimodal treatment regimen implied that there was need for an algorithm protocol for breast cancer women. Thus the need to improve the quality of treatment particularly in Nigeria by improved treatment documentation to overcome key barriers involving information exchange

    Intestinal fibrosis is reduced by early elimination of inflammation in a mouse model of IBD: Impact of a “Top‐Down” approach to intestinal fibrosis in mice

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    Background: The natural history of Crohn's disease follows a path of progression from an inflammatory to a fibrostenosing disease, with most patients requiring surgical resection of fibrotic strictures. Potent antiinflammatory therapies reduce inflammation but do not appear to alter the natural history of intestinal fibrosis. The aim of this study was to determine the relationship between intestinal inflammation and fibrogenesis and the impact of a very early “top‐down” interventional approach on fibrosis in vivo. Methods: In this study we removed the inflammatory stimulus from the Salmonella typhimurium mouse model of intestinal fibrosis by eradicating the S. typhimurium infection with levofloxacin at sequential timepoints during the infection. We evaluated the effect of this elimination of the inflammatory stimulus on the natural history of inflammation and fibrosis as determined by gross pathology, histopathology, mRNA expression, and protein expression. Results: Fibrogenesis is preceded by inflammation. Delayed eradication of the inflammatory stimulus by antibiotic treatment represses inflammation without preventing fibrosis. Early intervention significantly ameliorates but does not completely prevent subsequent fibrosis. Conclusions: This study demonstrates that intestinal fibrosis develops despite removal of an inflammatory stimulus and elimination of inflammation. Early intervention ameliorates but does not abolish subsequent fibrosis, suggesting that fibrosis, once initiated, is self‐propagating, suggesting that a very early top‐down interventional approach may have the most impact on fibrostenosing disease. (Inflamm Bowel Dis 2012;)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/90367/1/21812_ftp.pd

    Articles Occupancy Modeling of Woodpeckers: Maximizing Detections for Multiple Species with 3 Multiple Spatial Scales 4 5

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    Abstract 10 Numerous forest birds benefit from woodpecker presence or have similar habitat requirements. 11 Monitoring populations of forest woodpeckers can be useful for management decisions regarding 12 these and other forest species. Usefulness of monitoring efforts depends on methods employed 13 and the quality of resulting parameter estimates. Estimating the proportion of area occupied by a 14 species can be an attractive and affordable alternative to abundance or survival estimates. The 15 purpose of this study was to assess the distribution and area of occupancy for pileated 16 woodpeckers (Drycopus pileatus) and American three-toed woodpeckers (Picoides dorsalis) in 17 north-central Idaho, and to compare occupancy estimates using silent point counts, playback 18 surveys, and playback surveys that incorporated estimates of detection probability (p). We used 19 a hierarchical multi-scale framework that allowed estimation of occupancy at two spatial scales 20 and applied a removal design such that repeat visits to sampling stations was not necessary to 21 estimate p. The initial naĂŻve estimate of occupancy (using presence-absence data) for pileate

    Prior Helicobacter pylori infection ameliorates Salmonella typhimurium-induced colitis: Mucosal crosstalk between stomach and distal intestine

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    Background: Helicobacter pylori infection is associated with a lower risk of chronic autoimmune diseases including inflammatory bowel disease (IBD). H. pylori modulates the gastric immune response, decreasing the local inflammatory response to itself. In mice, chronic Salmonella typhimurium infection induces colitis similar to Crohn's disease, characterized by inflammation, which progresses toward fibrosis. The aim of this study was to determine whether prior H. pylori infection acts at a distance to modulate the immune response of S. typhimurium -induced colitis. Methods: Mice were infected with the mouse-adapted strain of H. pylori (SS1), followed by infection with S. typhimurium . The effect of H. pylori on colitis was determined by gross pathology, histopathology, cytokine response, and development of fibrosis in the cecum. Gastritis and systemic immune response was measured in response to infection. Results: H. pylori suppresses the Th17 response to S. typhimurium infection in the mouse cecum, but does not alter the Th2 or T-regulatory response or the development of fibrosis. H. pylori infection induces IL-10 in the mesenteric lymph nodes, suggesting an extragastric mechanism for immunomodulation. H. pylori / S. typhimurium coinfection decreases inflammation in both the cecum and the stomach. Conclusions: This study demonstrates a potential mechanism for the negative association between H. pylori and IBD in humans. H. pylori represses the lower gastrointestinal tract Th17 response to bacterially induced colitis via extragastric immunomodulatory effects, illustrating immunological crosstalk between the upper and lower gastrointestinal tract. (Inflamm Bowel Dis 2011;)Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/84386/1/21489_ftp.pd

    Iron Smelting in Sudan: Experimental Archaeology at The Royal City of Meroe

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    The Royal City of Meroe,ca.200 km north of Khartoum in the modern-day Republic of the Sudan, was an ancient capital of the Kingdom of Kush. From the 3rd century B.C. to the 4th century A.D., Kushite rulers controlledsigniïŹcantterritoryfromthebanksoftheNileatMeroe,inpartthroughtheirabilitytoensure the production of signiïŹcant quantities of iron. The extensive archaeological remains of Meroitic iron production have been investigated over decades, and recently a series of experimental iron smelts in a replica Meroitic furnace has shed new light on the archaeometallurgical evidence. The data generated during the smelting campaigns has provided an understanding of the type of iron ore used, the construction and operating parameters of the furnace, and the workshop space created by the ancient iron smelters during the later and post-Meroitic times.Qatar Sudan Archaeology Project Grant 037 UCL Qatar core fun

    On the role of in-plane damage mechanisms on the macroscopic behavior of SiC/SiC composites from complementary 2D and 3D in-situ investigations

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    International audienceThe mechanical behavior of architectured SiC/SiC composites is driven by different damage mechanisms whose understanding is required for building micromechanics-based models able to reproduce and predict its complexity. The kinematics of the surface, precisely analyzed using DIC at the textile pattern scale, exhibit a fiber realignment unexplained by the cracks observed at the surface. The missing mechanism, tracked by tomography in-situ testing (SOLEIL synchrotron), appears to be in-plane microcracking which does not emerge at the free surface of the composite

    The adaptation of a youth diabetes prevention program for Aboriginal children in Central Australia: community perspectives

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    This study reports on integrating community perspectives to adapt a family-focused, culturally appropriate behavioural intervention program to prevent diabetes among Aboriginal children (6-11 years) in Central Australia. A participatory action research approach was used to engage a range of service providers, cultural advisors, and family groups. Appropriateness, acceptability, content, and delivery of a prevention program within the Central Australian context were discussed through a series of workshops with twenty-five service providers and seven family groups separately. The data obtained were deductively coded for thematic analysis. Main findings included: (i) the strong need for a diabetes prevention program that is community owned, (ii) a flexible and culturally appropriate program delivered by upskilling community members as program facilitators, and (iii) consideration of social and environmental factors when implementing the program. It is recommended that a trial of the adapted prevention program for effectiveness and implementation is led by an Aboriginal community-controlled health service.Athira Rohit, Leisa McCarthy, Shiree Mack, Bronwyn Silver, Sabella Turner, Louise A. Baur, Karla Canuto, John Boffa, Dana Dabelea, Katherine A. Sauder, Louise Maple-Brown, and Renae Kirkha
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