440 research outputs found
Some arachnidan peptides with potential medical application
The search for new active drugs that can alleviate or cure different diseases is a constant challenge to researchers in the biological area and to the pharmaceutical industry. Historically, research has focused on the study of substances from plants. More recently, however, animal venoms have been attracting attention and studies have been successful in addressing treatment of accidents. Furthermore, venoms and their toxins have been considered good tools for prospecting for new active drugs or models for new therapeutic drugs. In this review, we discuss some possibilities of using different toxins, especially those from arachnid venoms, which have shown some potential application in diseases involving pain, hypertension, epilepsy and erectile dysfunction. A new generation of drugs is likely to emerge from peptides, including those found in animal venoms
Nutritional status and growth of indigenous Xavante children, Central Brazil
<p>Abstract</p> <p>Background</p> <p>The aim of this study was to characterize the nutritional status of Xavante Indian children less than 10 years of age in Central Brazil and to evaluate the hypothesis of an association between child nutrition and socioeconomic differentiation in this population.</p> <p>Methods</p> <p>A cross-sectional study was conducted in July 2006 that included all children under the age of 10 from the Xavante village Pimentel Barbosa in Mato Grosso, Brazil. The data collected included weight, height, and sociodemographic information. Sociodemographic data were used to generate two indices ("income" and "wealth") and to determine the proportion of adults in each household. Descriptive analyses were performed for weight-for-age (W/A), height-for-age (H/A), and weight-for-height (W/H) using the NCHS and the WHO growth references. Univariate and multivariate analyses were conducted using H/A and W/A as a response variables.</p> <p>Results</p> <p>Of a total of 246 children under the age of ten residing in the village, 232 (94.3%) were evaluated. Following the NCHS reference, 5.6% of children under the age of ten presented low W/A and 14.7% presented low H/A. Among children under the age of five, deficit percentages for weight and height were 4.5% and 29.9%, respectively, following the WHO curves. Among children < 2 years of age, H/A index variability was found to be directly related to child's age and inversely related to the proportion of adults in the household. Maternal BMI was positively associated with growth for children from 2 to 4 years of age, explaining 11.5% of the z-score variability for the H/A index. For children 5 years of age and older, the wealth index and maternal height were positively associated with H/A. No significant associations were found using W/A as the dependent variable.</p> <p>Conclusion</p> <p>This study demonstrated that undernutrition, in particular linear growth deficit, is a notable health issue for Xavante children. These findings contrast with the nutritional profile observed among Brazilian children nationally, which is characterized by a sharp decline in child undernutrition in recent decades, even in the poorest regions of the country. This discrepancy calls attention to the persistent health disparities that exist between indigenous and non-indigenous people in Brazil.</p
Planck intermediate results. XLI. A map of lensing-induced B-modes
The secondary cosmic microwave background (CMB) -modes stem from the
post-decoupling distortion of the polarization -modes due to the
gravitational lensing effect of large-scale structures. These lensing-induced
-modes constitute both a valuable probe of the dark matter distribution and
an important contaminant for the extraction of the primary CMB -modes from
inflation. Planck provides accurate nearly all-sky measurements of both the
polarization -modes and the integrated mass distribution via the
reconstruction of the CMB lensing potential. By combining these two data
products, we have produced an all-sky template map of the lensing-induced
-modes using a real-space algorithm that minimizes the impact of sky masks.
The cross-correlation of this template with an observed (primordial and
secondary) -mode map can be used to measure the lensing -mode power
spectrum at multipoles up to . In particular, when cross-correlating with
the -mode contribution directly derived from the Planck polarization maps,
we obtain lensing-induced -mode power spectrum measurement at a significance
level of , which agrees with the theoretical expectation derived
from the Planck best-fit CDM model. This unique nearly all-sky
secondary -mode template, which includes the lensing-induced information
from intermediate to small () angular scales, is
delivered as part of the Planck 2015 public data release. It will be
particularly useful for experiments searching for primordial -modes, such as
BICEP2/Keck Array or LiteBIRD, since it will enable an estimate to be made of
the lensing-induced contribution to the measured total CMB -modes.Comment: 20 pages, 12 figures; Accepted for publication in A&A; The B-mode map
is part of the PR2-2015 Cosmology Products; available as Lensing Products in
the Planck Legacy Archive http://pla.esac.esa.int/pla/#cosmology; and
described in the 'Explanatory Supplement'
https://wiki.cosmos.esa.int/planckpla2015/index.php/Specially_processed_maps#2015_Lensing-induced_B-mode_ma
Integrating chromosomal aberrations and gene expression profiles to dissect rectal tumorigenesis
<p>Abstract</p> <p>Background</p> <p>Accurate staging of rectal tumors is essential for making the correct treatment choice. In a previous study, we found that loss of 17p, 18q and gain of 8q, 13q and 20q could distinguish adenoma from carcinoma tissue and that gain of 1q was related to lymph node metastasis. In order to find markers for tumor staging, we searched for candidate genes on these specific chromosomes.</p> <p>Methods</p> <p>We performed gene expression microarray analysis on 79 rectal tumors and integrated these data with genomic data from the same sample series. We performed supervised analysis to find candidate genes on affected chromosomes and validated the results with qRT-PCR and immunohistochemistry.</p> <p>Results</p> <p>Integration of gene expression and chromosomal instability data revealed similarity between these two data types. Supervised analysis identified up-regulation of <it>EFNA1 </it>in cases with 1q gain, and <it>EFNA1 </it>expression was correlated with the expression of a target gene (<it>VEGF</it>). The <it>BOP1 </it>gene, involved in ribosome biogenesis and related to chromosomal instability, was over-expressed in cases with 8q gain. <it>SMAD2 </it>was the most down-regulated gene on 18q, and on 20q, <it>STMN3 </it>and <it>TGIF2 </it>were highly up-regulated. Immunohistochemistry for SMAD4 correlated with <it>SMAD2 </it>gene expression and 18q loss.</p> <p>Conclusion</p> <p>On basis of integrative analysis this study identified one well known CRC gene (<it>SMAD2</it>) and several other genes (<it>EFNA1, BOP1, TGIF2 </it>and <it>STMN3</it>) that possibly could be used for rectal cancer characterization.</p
Planck 2015 results: I. Overview of products and scientific results
The European Space Agency's Planck satellite, which is dedicated to studying the early Universe and its subsequent evolution, was launched on 14 May 2009. It scanned the microwave and submillimetre sky continuously between 12 August 2009 and 23 October 2013. In February 2015, ESA and the Planck Collaboration released the second set of cosmology products based ondata from the entire Planck mission, including both temperature and polarization, along with a set of scientific and technical papers and a web-based explanatory supplement. This paper gives an overview of the main characteristics of the data and the data products in the release, as well as the associated cosmological and astrophysical science results and papers. The data products include maps of the cosmic microwave background (CMB), the thermal Sunyaev-Zeldovich effect, diffuse foregrounds in temperature and polarization, catalogues of compact Galactic and extragalactic sources (including separate catalogues of Sunyaev-Zeldovich clusters and Galactic cold clumps), and extensive simulations of signals and noise used in assessing uncertainties and the performance of the analysis methods. The likelihood code used to assess cosmological models against the Planck data is described, along with a CMB lensing likelihood. Scientific results include cosmological parameters derived from CMB power spectra, gravitational lensing, and cluster counts, as well as constraints on inflation, non-Gaussianity, primordial magnetic fields, dark energy, and modified gravity, and new results on low-frequency Galactic foregrounds
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Planck intermediate results: LI. Features in the cosmic microwave background temperature power spectrum and shifts in cosmological parameters
The six parameters of the standard ΛCDM model have best-fit values derived from the Planck temperature power spectrum that are shifted somewhat from the best-fit values derived from WMAP data. These shifts are driven by features in the Planck temperature power spectrum at angular scales that had never before been measured to cosmic-variance level precision. We have investigated these shifts to determine whether they are within the range of expectation and to understand their origin in the data. Taking our parameter set to be the optical depth of the reionized intergalactic medium, the baryon density ω b , the matter density ω m , the angular size of the sound horizon the spectral index of the primordial power spectrum, n s , and A s e -2τ (where A s is the amplitude of the primordial power spectrum), we have examined the change in best-fit values between a WMAP-like large angular-scale data set (with multipole moment 800, or splitting at a different multipole, yields similar results. We examined the 800 power spectrum data and find that the features there that drive these shifts are a set of oscillations across a broad range of angular scales. Although they partly appear similar to the effects of enhanced gravitational lensing, the shifts in ΛCDM parameters that arise in response to these features correspond to model spectrum changes that are predominantly due to non-lensing effects; the only exception is, which, at fixed A s e -2τ , affects the > 800 temperature power spectrum solely through the associated change in A s and the impact of that on the lensing potential power spectrum. We also ask, "what is it about the power spectrum at < 800 that leads to somewhat different best-fit parameters than come from the full range?" We find that if we discard the data at < 30, where there is a roughly 2σ downward fluctuation in power relative to the model that best fits the full range, the < 800 best-fit parameters shift significantly towards the < 2500 best-fit parameters. In contrast, including < 30, this previously noted "low-deficit" drives n s up and impacts parameters correlated with n s , such as ω m and H 0 . As expected, the < 30 data have a much greater impact on the < 800 best fit than on the < 2500 best fit. So although the shifts are not very significant, we find that they can be understood through the combined effects of an oscillatory-like set of high-residuals and the deficit in low-power, excursions consistent with sample variance that happen to map onto changes in cosmological parameters. Finally, we examine agreement between PlanckTT data and two other CMB data sets, namely the Planck lensing reconstruction and the TT power spectrum measured by the South Pole Telescope, again finding a lack of convincing evidence of any significant deviations in parameters, suggesting that current CMB data sets give an internally consistent picture of the ΛCDM model
A comparative study between mixed-type tumours from human salivary and canine mammary glands
<p>Abstract</p> <p>Background</p> <p>In comparative pathology, canine mammary tumours have special interest because of their similarities with human breast cancer. Mixed tumours are uncommon lesions in the human breast, but they are found most frequently in the mammary gland of the female dogs and in the human salivary glands. The aim of the study was to compare clinical, morphological and immunohistochemical features of human salivary and canine mammary gland mixed tumours, in order to evaluate the latter as an experimental model for salivary gland tumours.</p> <p>Methods</p> <p>Ten examples of each mixed tumour type (human pleomorphic adenoma and carcinomas ex-pleomorphic adenomas and canine mixed tumour and metaplastic carcinoma) were evaluated. First, clinical and morphologic aspects of benign and malignant variants were compared between the species. Then, streptavidin-biotin-peroxidase immunohistochemistry was performed to detect the expression of cytokeratins, vimentin, p63 protein, estrogen receptor, β-catenin, and E-cadherin.</p> <p>Results</p> <p>After standardization, similar age and site distributions were observed in human and canine tumours. Histological similarities were identified in the comparison of the benign lesions as well. Metaplastic carcinomas also resembled general aspects of carcinomas ex-pleomorphic adenomas in morphological evaluation. Additionally, immunohistochemical staining further presented similar antigenic expression between lesions.</p> <p>Conclusion</p> <p>There are many similar features between human salivary and canine mammary gland mixed tumours. This observation is of great relevance for those interested in the study and management of salivary gland tumours, since canine lesions may constitute useful comparative models for their investigations.</p
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Planck intermediate results: XLVI. Reduction of large-scale systematic effects in HFI polarization maps and estimation of the reionization optical depth
© 2016 ESO. This paper describes the identification, modelling, and removal of previously unexplained systematic effects in the polarization data of the Planck High Frequency Instrument (HFI) on large angular scales, including new mapmaking and calibration procedures, new and more complete end-to-end simulations, and a set of robust internal consistency checks on the resulting maps. These maps, at 100, 143, 217, and 353 GHz, are early versions of those that will be released in final form later in 2016. The improvements allow us to determine the cosmic reionization optical depth τ using, for the first time, the low-multipole EE data from HFI, reducing significantly the central value and uncertainty, and hence the upper limit. Two different likelihood procedures are used to constrain τ from two estimators of the CMB E-and B-mode angular power spectra at 100 and 143 GHz, after debiasing the spectra from a small remaining systematic contamination. These all give fully consistent results. A further consistency test is performed using cross-correlations derived from the Low Frequency Instrument maps of the Planck 2015 data release and the new HFI data. For this purpose, end-to-end analyses of systematic effects from the two instruments are used to demonstrate the near independence of their dominant systematic error residuals. The tightest result comes from the HFI-based τ posterior distribution using the maximum likelihood power spectrum estimator from EE data only, giving a value 0.055 ± 0.009. In a companion paper these results are discussed in the context of the best-fit PlanckΛCDM cosmological model and recent models of reionization
Tumor immunosurveillance in human cancers
Until now, the anatomic extent of tumor (TNM classification) has been by far the most important factor to predict the prognosis of colorectal cancer patients. However, in recent years, data collected from large cohorts of human cancers demonstrated that the immune contexture of the primary tumors is an essential prognostic factor for patients’ disease-free and overall survival. Tumoral and immunological markers predicted by systems biology methods are involved in the shaping of an efficient immune reaction and can serve as targets for novel therapeutic approaches. Global analysis of tumor microenvironment showed that the nature, the functional orientation, the density, and the location of adaptive immune cells within distinct tumor regions influence the risk of relapse events. The density and the immune cell location within the tumor have a prognostic value that is superior to the TNM classification, and tumor invasion is statistically dependent on the host-immune reaction. Thus, the strength of the immune reaction could advance our understanding of cancer evolution and have important consequences in clinical practice
Relative Burden of Large CNVs on a Range of Neurodevelopmental Phenotypes
While numerous studies have implicated copy number variants (CNVs) in a range of neurological phenotypes, the impact relative to disease severity has been difficult to ascertain due to small sample sizes, lack of phenotypic details, and heterogeneity in platforms used for discovery. Using a customized microarray enriched for genomic hotspots, we assayed for large CNVs among 1,227 individuals with various neurological deficits including dyslexia (376), sporadic autism (350), and intellectual disability (ID) (501), as well as 337 controls. We show that the frequency of large CNVs (>1 Mbp) is significantly greater for ID–associated phenotypes compared to autism (p = 9.58×10−11, odds ratio = 4.59), dyslexia (p = 3.81×10−18, odds ratio = 14.45), or controls (p = 2.75×10−17, odds ratio = 13.71). There is a striking difference in the frequency of rare CNVs (>50 kbp) in autism (10%, p = 2.4×10−6, odds ratio = 6) or ID (16%, p = 3.55×10−12, odds ratio = 10) compared to dyslexia (2%) with essentially no difference in large CNV burden among dyslexia patients compared to controls. Rare CNVs were more likely to arise de novo (64%) in ID when compared to autism (40%) or dyslexia (0%). We observed a significantly increased large CNV burden in individuals with ID and multiple congenital anomalies (MCA) compared to ID alone (p = 0.001, odds ratio = 2.54). Our data suggest that large CNV burden positively correlates with the severity of childhood disability: ID with MCA being most severely affected and dyslexics being indistinguishable from controls. When autism without ID was considered separately, the increase in CNV burden was modest compared to controls (p = 0.07, odds ratio = 2.33)
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