Contrasting prefrontal cortex contributions to episodic memory dysfunction in behavioural variant frontotemporal dementia and alzheimer's disease

Recent evidence has questioned the integrity of episodic memory in behavioural variant frontotemporal dementia (bvFTD), where recall performance is impaired to the same extent as in Alzheimer's disease (AD). While these deficits appear to be mediated by divergent patterns of brain atrophy, there is evidence to suggest that certain prefrontal regions are implicated across both patient groups. In this study we sought to further elucidate the dorsolateral (DLPFC) and ventromedial (VMPFC) prefrontal contributions to episodic memory impairment in bvFTD and AD. Performance on episodic memory tasks and neuropsychological measures typically tapping into either DLPFC or VMPFC functions was assessed in 22 bvFTD, 32 AD patients and 35 age- and education-matched controls. Behaviourally, patient groups did not differ on measures of episodic memory recall or DLPFC-mediated executive functions. BvFTD patients were significantly more impaired on measures of VMPFC-mediated executive functions. Composite measures of the recall, DLPFC and VMPFC task scores were covaried against the T1 MRI scans of all participants to identify regions of atrophy correlating with performance on these tasks. Imaging analysis showed that impaired recall performance is associated with divergent patterns of PFC atrophy in bvFTD and AD. Whereas in bvFTD, PFC atrophy covariates for recall encompassed both DLPFC and VMPFC regions, only the DLPFC was implicated in AD. Our results suggest that episodic memory deficits in bvFTD and AD are underpinned by divergent prefrontal mechanisms. Moreover, we argue that these differences are not adequately captured by existing neuropsychological measures

Dysplasia of the Upper Aerodigestive Tract Squamous Epithelium

Dysplasia of the oral, laryngeal and oropharyngeal stratified squamous epithelia is a microscopically defined change that may occur in clinically identifiable lesions including erythroplakia, leukoplakia and erythroleukoplakia, lesions that convey a heightened risk for carcinomatous progression. Dysplastic lesions have been classified microscopically according to degree of cytologic atypia and changes in architectural patterns, usually on a three part or four part gradation scale. Vocal cord epithelial lesions are graded according to either the Ljubljana or the World Health Organization (WHO) system whereas oral dysplasias are generally classified according to WHO criteria. Cytologically atypical cells are considered to represent precancerous changes predicting an increase risk for carcinomatous transformation. Inter- and intra-rater reliability studies among pathologists have disclosed low correlation coefficients for four part grading systems, whereas improved agreement is achieved (kappa correlation values) using the Ljubljana systems. Evidence forwarded by some studies supports the prognostic value of progressively severe dysplastic changes for carcinomatous transformation; however, some studies indicate that the presence of a clinically defined lesion without microscopic evidence of dysplasia also connotes increased risk for carcinomatous transformation. Loss of heterozygosity (LOH) at 3p and 9p microsatellite domains, DNA ploidy analysis and nuclear image analyses may have predictive value as molecular and histomorphological biomarkers

Circumstellar disks and planets. Science cases for next-generation optical/infrared long-baseline interferometers

We present a review of the interplay between the evolution of circumstellar disks and the formation of planets, both from the perspective of theoretical models and dedicated observations. Based on this, we identify and discuss fundamental questions concerning the formation and evolution of circumstellar disks and planets which can be addressed in the near future with optical and infrared long-baseline interferometers. Furthermore, the importance of complementary observations with long-baseline (sub)millimeter interferometers and high-sensitivity infrared observatories is outlined.Comment: 83 pages; Accepted for publication in "Astronomy and Astrophysics Review"; The final publication is available at http://www.springerlink.co

Comparison of hemodynamic and nutritional parameters between older persons practicing regular physical activity, nonsmokers and ex-smokers

<p>Abstract</p> <p>Background</p> <p>Sedentary lifestyle combined with smoking, contributes to the development of a set of chronic diseases and to accelerating the course of aging. The aim of the study was to compare the hemodynamic and nutritional parameters between elderly persons practicing regular physical activity, nonsmokers and ex-smokers.</p> <p>Methods</p> <p>The sample was comprised of 40 elderly people practicing regular physical activity for 12 months, divided into a Nonsmoker Group and an Ex-smoker Group. During a year four trimestrial evaluations were performed, in which the hemodynamic (blood pressure, heart rate- HR and VO₂) and nutritional status (measured by body mass index) data were collected. The paired t-test and t-test for independent samples were applied in the intragroup and intergroup analysis, respectively.</p> <p>Results</p> <p>The mean age of the groups was 68.35 years, with the majority of individuals in the Nonsmoker Group being women (n = 15) and the Ex-smoker Group composed of men (n = 11). In both groups the variables studied were within the limits of normality for the age. HR was diminished in the Nonsmoker Group in comparison with the Ex-smoker Group (p = 0.045) between the first and last evaluation. In the intragroup analysis it was verified that after one year of exercise, there was significant reduction in the HR in the Nonsmoker Group (p = 0.002) and a significant increase in VO₂for the Ex-smoker Group (p = 0.010). There are no significant differences between the hemodynamic and nutritional conditions in both groups.</p> <p>Conclusion</p> <p>In elderly persons practicing regular physical activity, it was observed that the studied variables were maintained over the course of a year, and there was no association with the history of smoking, except for HR and VO₂.</p

The Evolution of Compact Binary Star Systems

We review the formation and evolution of compact binary stars consisting of white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and BHs are thought to be the primary astrophysical sources of gravitational waves (GWs) within the frequency band of ground-based detectors, while compact binaries of WDs are important sources of GWs at lower frequencies to be covered by space interferometers (LISA). Major uncertainties in the current understanding of properties of NSs and BHs most relevant to the GW studies are discussed, including the treatment of the natal kicks which compact stellar remnants acquire during the core collapse of massive stars and the common envelope phase of binary evolution. We discuss the coalescence rates of binary NSs and BHs and prospects for their detections, the formation and evolution of binary WDs and their observational manifestations. Special attention is given to AM CVn-stars -- compact binaries in which the Roche lobe is filled by another WD or a low-mass partially degenerate helium-star, as these stars are thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure

The Impact of Long-Term Exposure to Space Environment on Adult Mammalian Organisms: A Study on Mouse Thyroid and Testis

Hormonal changes in humans during spaceflight have been demonstrated but the underlying mechanisms are still unknown. To clarify this point thyroid and testis/epididymis, both regulated by anterior pituitary gland, have been analyzed on long-term space-exposed male C57BL/10 mice, either wild type or pleiotrophin transgenic, overexpressing osteoblast stimulating factor-1. Glands were submitted to morphological and functional analysis

Sialyl Lewis X Expression and Lymphatic Microvessel Density in Primary Tumors of Node-negative Colorectal Cancer Patients Predict Disease Recurrence

Up to 30% of curatively resected colorectal cancer patients with tumor-negative lymph nodes, show disease recurrence. We assessed whether these high-risk patients can be identified by examining primary tumors for the following blood and lymphatic vasculature markers: A) sialyl Lewis X (sLeX), vascular endothelial growth factor (VEGF)-C and VEGF-D expression; B) blood and lymphatic microvessel density (BMVD/LMVD); and C) the presence of blood and lymphatic vessel invasion. Thirty-six cases (disease recurrence within 5 years) and 72 controls (no disease recurrence for at least 5 years) were selected in a case-control design. Tumor sections were stained by antibodies CSLEX1 (sLeX), anti-VEGF-C, anti-VEGF-D, anti-CD31 (BMVD) or D2–40 (LMVD) to determine the parameters as mentioned above. A multivariate analysis showed sLeX expression and high LMVD (odds ratio 5.1, 95% confidence interval 1.3–20.0 and odds ratio 3.1, 95% confidence interval 1.0–10.0, respectively) to be independent factors predicting disease recurrence. Expression of sLeX correlated with liver metastases (P = 0.015). A high LMVD was related to regional intra-abdominal or intrapelvic metastases in lymph nodes and distant metastases other than in the liver and lungs such as peritoneum, bones, brain and adrenal glands (P = 0.004). A high BMVD in the invasive front correlated with lung metastases (P = 0.018). We show that high-risk node-negative colorectal cancer patients can be identified by primary tumor assessment for sLeX expression and LMVD. Our results are consistent with the notion that both lymphatic and hematogenous metastasis play a role in colorectal cancer

Compressed representation of a partially defined integer function over multiple arguments

In OLAP (OnLine Analitical Processing) data are analysed in an n-dimensional cube. The cube may be represented as a partially defined function over n arguments. Considering that often the function is not defined everywhere, we ask: is there a known way of representing the function or the points in which it is defined, in a more compact manner than the trivial one

Search for new phenomena in final states with an energetic jet and large missing transverse momentum in pp collisions at √ s = 8 TeV with the ATLAS detector

Results of a search for new phenomena in final states with an energetic jet and large missing transverse momentum are reported. The search uses 20.3 fb−1 of √ s = 8 TeV data collected in 2012 with the ATLAS detector at the LHC. Events are required to have at least one jet with pT > 120 GeV and no leptons. Nine signal regions are considered with increasing missing transverse momentum requirements between Emiss T > 150 GeV and Emiss T > 700 GeV. Good agreement is observed between the number of events in data and Standard Model expectations. The results are translated into exclusion limits on models with either large extra spatial dimensions, pair production of weakly interacting dark matter candidates, or production of very light gravitinos in a gauge-mediated supersymmetric model. In addition, limits on the production of an invisibly decaying Higgs-like boson leading to similar topologies in the final state are presente

Skeletal Muscle Phenotypically Converts and Selectively Inhibits Metastatic Cells in Mice

Skeletal muscle is rarely a site of malignant metastasis; the molecular and cellular basis for this rarity is not understood. We report that myogenic cells exert pronounced effects upon co-culture with metastatic melanoma (B16-F10) or carcinoma (LLC1) cells including conversion to the myogenic lineage in vitro and in vivo, as well as inhibition of melanin production in melanoma cells coupled with cytotoxic and cytostatic effects. No effect is seen with non-tumorigenic cells. Tumor suppression assays reveal that the muscle-mediated tumor suppressor effects do not generate resistant clones but function through the down-regulation of the transcription factor MiTF, a master regulator of melanocyte development and a melanoma oncogene. Our findings point to skeletal muscle as a source of therapeutic agents in the treatment of metastatic cancers