268 resultados para likelihood profile function
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Background: Hexamerins are hemocyanin-derived proteins that have lost the ability to bind copper ions and transport oxygen; instead, they became storage proteins. The current study aimed to broaden our knowledge on the hexamerin genes found in the honey bee genome by exploring their structural characteristics, expression profiles, evolution, and functions in the life cycle of workers, drones and queens. Results: The hexamerin genes of the honey bee (hex 70a, hex 70b, hex 70c and hex 110) diverge considerably in structure, so that the overall amino acid identity shared among their deduced protein subunits varies from 30 to 42%. Bioinformatics search for motifs in the respective upstream control regions (UCRs) revealed six overrepresented motifs including a potential binding site for Ultraspiracle (Usp), a target of juvenile hormone (JH). The expression of these genes was induced by topical application of JH on worker larvae. The four genes are highly transcribed by the larval fat body, although with significant differences in transcript levels, but only hex 110 and hex 70a are re-induced in the adult fat body in a caste-and sex-specific fashion, workers showing the highest expression. Transcripts for hex 110, hex 70a and hex70b were detected in developing ovaries and testes, and hex 110 was highly transcribed in the ovaries of egg-laying queens. A phylogenetic analysis revealed that HEX 110 is located at the most basal position among the holometabola hexamerins, and like HEX 70a and HEX 70c, it shares potential orthology relationship with hexamerins from other hymenopteran species. Conclusions: Striking differences were found in the structure and developmental expression of the four hexamerin genes in the honey bee. The presence of a potential binding site for Usp in the respective 5' UCRs, and the results of experiments on JH level manipulation in vivo support the hypothesis of regulation by JH. Transcript levels and patterns in the fat body and gonads suggest that, in addition to their primary role in supplying amino acids for metamorphosis, hexamerins serve as storage proteins for gonad development, egg production, and to support foraging activity. A phylogenetic analysis including the four deduced hexamerins and related proteins revealed a complex pattern of evolution, with independent radiation in insect orders.
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Background and Purpose: Carbon dioxide pneumoperitoneum is associated with significant hypercarbia and acidosis. The aim of this study is to evaluate the effects of carbon dioxide and helium pneumoperitoneum on renal function. Materials and Methods: Thirty adult dogs were put randomly into one of three groups ( n = 10 animals each): group A - pneumoperitoneum not performed; group B - CO2 pneumoperitoneum; and group C - helium pneumoperitoneum. The groups were analyzed with consideration given to body weight, hematologic values, hemodynamic parameters ( heart rate, mean arterial pressure, central venous pressure, cardiac output, stroke volume, systemic vascular resistance, pulmonary vascular resistance, left cardiac work index, cardiac index, mean pulmonary artery pressure, and pulmonary capillary wedge pressure), and renal function ( plasma renin activity, urinary output, creatinine clearance, and sodium excretory fraction). Results: An accentuated decrease in urinary output was observed during pneumoperitoneum in groups B and C compared to the control group. In groups B and C, creatinine clearance declined significantly during pneumoperitoneum in comparison to group A, but after deflation a faster recovery of glomerular filtration was noticed for group C, and a significant increase in sodium excretory fraction was seen for group B. On the other hand, in comparison to the control group, group B had a significant increase in plasma renin activity, with late recovery of glomerular function. Conclusion: Helium ameliorates renal alterations when used for pneumoperitoneum, and it might be used for patients with compromised renal function who have to undergo laparoscopic surgery.
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Background Peripheral muscle strength and endurance are decreased in patients with chronic pulmonary diseases and seem to contribute to patients' exercise intolerance. However, the authors are not aware of any studies evaluating peripheral muscle function in children with asthma. It seems to be implied that children with asthma have lower aerobic fitness, but there are limited studies comparing the aerobic capacity of children with and without asthma. The present study aimed to evaluate muscle strength and endurance in children with persistent asthma and their association with aerobic capacity and inhaled corticosteroid consumption. Methods Forty children with mild persistent asthma (MPA) or severe persistent asthma (SPA) (N=20 each) and 20 children without asthma (control group) were evaluated. Upper (pectoralis and latissimus dorsi) and lower (quadriceps) muscle strength and endurance were assessed, and cardiopulmonary exercise testing was performed. Inhaled corticosteroid consumption during the last 6 and 24 months was also quantified. Results Children with SPA presented a reduction in peak oxygen consumption (VO(2)) (28.2 +/- 8.1 vs 34.7 +/- 6.9 ml/kg/min; p<0.01) and quadriceps endurance (43.1 +/- 6.7 vs 80.9 +/- 11.9 repetitions; p<0.05) compared with the control group, but not the MPA group (31.5 +/- 6.1 ml/kg/min and 56.7 +/- 47.7 repetitions respectively; p>0.05). Maximal upper and lower muscle strength was preserved in children with both mild and severe asthma (p>0.05). Finally, the authors observed that lower muscle endurance weakness was not associated with reductions in either peak VO(2) (r=0.22, p>0.05) or corticosteroid consumption (r=-0.31, p>0.05) in children with asthma. Conclusion The findings suggest that cardiopulmonary exercise and lower limb muscle endurance should be a priority during physical training programs for children with severe asthma.
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The action of the parasympathetic nerves on the heart is made through a group of neurons located on the surface of the atria. This study evaluated the effect of a chronic training protocol on the number and sizes of the cardiac neurons of Wistar rats. Whole mount preparations of the atria of 12-month old male sedentary and trained rats (40 weeks of running on a treadmill 3 times a week, 16 m/min) were assessed for number and size (maximal cellular profile area) of the cardiac neurons. The cardiac neurons were ascertained by using the NADH-diaphorase technique that stains the cell bodies of the neurons in dark blue. The, number of cardiac neurons in the trained rats (P>0.05) did not change significantly. In the sedentary group there were small, medium sized and large neurons. However there was a notable increase in the percentage of small neurons in the rats submitted to the training compared to the sedentary group (P<0.05). Previous studies have shown that electrophysiologically, the small neurons are more easily excitable than the large neurons. It is possible that the results of the present work reflect an adaptation mechanism of the cardiac neurons presumably with the objective of increasing the excitability of the neurons for the vagal action and resulting facilitation of the sinusal bradycardia observed at rest and in the exercise. We concluded that the training affects significantly the size of the cardiac neurons in Wistar rats. (Biol.Sport 26.245-254, 2009)
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Background: Cardiac remodeling is generally an adverse sign and is associated with heart failure (HF) progression. NFkB, an important transcription factor involved in many cell survival pathways, has been implicated in the remodeling process, but its role in the heart is still controversial. Recently, a promoter polymorphism associated with a lesser activation of the NFKB1 gene was also associated with Dilated Cardiomyopathy. The purpose of this study was to evaluate the association of this polymorphism with clinical and functional characteristics of heart failure patients of different etiologies. Methods: A total of 493 patients with HF and 916 individuals from a cohort of individuals from the general population were investigated. The NFKB1-94 insertion/deletion ATTG polymorphism was genotyped by High Resolution Melt discrimination. Allele and genotype frequencies were compared between groups. In addition, frequencies or mean values of different phenotypes associated with cardiovascular disease were compared between genotype groups. Finally, patients were prospectively followed-up for death incidence and genotypes for the polymorphism were compared regarding disease onset and mortality incidence in HF patients. Results: We did not find differences in genotype and allelic frequencies between cases and controls. Interestingly, we found an association between the ATTG(1)/ATTG(1) genotype with right ventricle diameter (P = 0.001), left ventricle diastolic diameter (P = 0.04), and ejection fraction (EF) (P = 0.016), being the genotype ATTG(1)/ATTG(1) more frequent in patients with EF lower than 50% (P = 0.01). Finally, we observed a significantly earlier disease onset in ATTG(1)/ATTG(1) carriers. Conclusion: There is no genotype or allelic association between the studied polymorphism and the occurrence of HF in the tested population. However, our data suggest that a diminished activation of NFKB1, previously associated with the ATTG(1)/ATTG(1) genotype, may act modulating on the onset of disease and, once the individual has HF, the genotype may modulate disease severity by increasing cardiac remodeling and function deterioration.
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Background: Cell therapy approaches for biologic cardiac repair hold great promises, although basic fundamental issues remain poorly understood. In the present study we examined the effects of timing and routes of administration of bone marrow cells (BMC) post-myocardial infarction (MI) and the efficacy of an injectable biopolymer scaffold to improve cardiac cell retention and function. Methodology/Principal Findings: (99m)Tc-labeled BMC (6x10(6) cells) were injected by 4 different routes in adult rats: intravenous (IV), left ventricular cavity (LV), left ventricular cavity with temporal aorta occlusion (LV(+)) to mimic coronary injection, and intramyocardial (IM). The injections were performed 1, 2, 3, or 7 days post-MI and cell retention was estimated by gamma-emission counting of the organs excised 24 hs after cell injection. IM injection improved cell retention and attenuated cardiac dysfunction, whereas IV, LV or LV* routes were somewhat inefficient (< 1%). Cardiac BMC retention was not influenced by timing except for the IM injection that showed greater cell retention at 7 (16%) vs. 1, 2 or 3 (average of 7%) days post-MI. Cardiac cell retention was further improved by an injectable fibrin scaffold at day 3 post-MI (17 vs. 7%), even though morphometric and function parameters evaluated 4 weeks later displayed similar improvements. Conclusions/Significance: These results show that cells injected post-MI display comparable tissue distribution profile regardless of the route of injection and that there is no time effect for cardiac cell accumulation for injections performed 1 to 3 days post-MI. As expected the IM injection is the most efficient for cardiac cell retention, it can be further improved by co-injection with a fibrin scaffold and it significantly attenuates cardiac dysfunction evaluated 4 weeks post myocardial infarction. These pharmacokinetic data obtained under similar experimental conditions are essential for further development of these novel approaches.
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Background: The MASS IV-DM Trial is a large project from a single institution, the Heart Institute (InCor), University of Sao Paulo Medical School, Brazil to study ventricular function and coronary arteries in patients with type 2 diabetes mellitus. Methods/Design: The study will enroll 600 patients with type 2 diabetes who have angiographically normal ventricular function and coronary arteries. The goal of the MASS IV-DM Trial is to achieve a long-term evaluation of the development of coronary atherosclerosis by using angiograms and coronary-artery calcium scan by electron-beam computed tomography at baseline and after 5 years of follow-up. In addition, the incidence of major cardiovascular events, the dysfunction of various organs involved in this disease, particularly microalbuminuria and renal function, will be analyzed through clinical evaluation. In addition, an effort will be made to investigate in depth the presence of major cardiovascular risk factors, especially the biochemical profile, metabolic syndrome inflammatory activity, oxidative stress, endothelial function, prothrombotic factors, and profibrinolytic and platelet activity. An evaluation will be made of the polymorphism as a determinant of disease and its possible role in the genesis of micro- and macrovascular damage. Discussion: The MASS IV-DM trial is designed to include diabetic patients with clinically suspected myocardial ischemia in whom conventional angiography shows angiographically normal coronary arteries. The result of extensive investigation including angiographic follow-up by several methods, vascular reactivity, pro-thrombotic mechanisms, genetic and biochemical studies may facilitate the understanding of so-called micro- and macrovascular disease of DM.
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Background: Celery (Apium graveolens) represents a relevant allergen source that can elicit severe reactions in the adult population. To investigate the sensitization prevalence and cross-reactivity of Api g 2 from celery stalks in a Mediterranean population and in a mouse model. Methodology: 786 non-randomized subjects from Italy were screened for IgE reactivity to rApi g 2, rArt v 3 (mugwort pollen LTP) and nPru p 3 (peach LTP) using an allergen microarray. Clinical data of 32 selected patients with reactivity to LTP under investigation were evaluated. Specific IgE titers and cross-inhibitions were performed in ELISA and allergen microarray. Balb/c mice were immunized with purified LTPs; IgG titers were determined in ELISA and mediator release was examined using RBL-2H3 cells. Simulated endolysosomal digestion was performed using microsomes obtained from human DCs. Results: IgE testing showed a sensitization prevalence of 25.6% to Api g 2, 18.6% to Art v 3, and 28.6% to Pru p 3 and frequent co-sensitization and correlating IgE-reactivity was observed. 10/32 patients suffering from LTP-related allergy reported symptoms upon consumption of celery stalks which mainly presented as OAS. Considerable IgE cross-reactivity was observed between Api g 2, Art v 3, and Pru p 3 with varying inhibition degrees of individual patients' sera. Simulating LTP mono-sensitization in a mouse model showed development of more congruent antibody specificities between Api g 2 and Art v 3. Notably, biologically relevant murine IgE cross-reactivity was restricted to the latter and diverse from Pru p 3 epitopes. Endolysosomal processing of LTP showed generation of similar clusters, which presumably represent T-cell peptides. Conclusions: Api g 2 represents a relevant celery stalk allergen in the LTP-sensitized population. The molecule displays common B cell epitopes and endolysosomal peptides that encompass T cell epitopes with pollen and plant-food derived LTP.
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The molecular pathogenesis of myelodysplastic syndromes (MDS) is poorly understood. In order to expand our knowledge of genetic defects in MDS, we determined the overall profile of genes expressed in bone marrow from patients with refractory anemia with excess blasts ( RAEB) by serial analysis of gene expression ( SAGE). The present report describes a partial transcriptome of RAEB bone marrow derived from 56,694 sequenced tags that provides information about expressed gene products. This is the first attempt to determine an overall profile of gene expression specifically in RAEB at diagnosis using SAGE, which should be useful in the understanding of the physiopathology of MDS and in identifying the genes involved.
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Chagas disease, caused by infection with Trypanosoma cruzi, is an important cause of cardiovascular disease. It is increasingly clear that parasite-derived prostaglandins potently modulate host response and disease progression. Here, we report that treatment of experimental T. cruzi infection (Brazil strain) beginning 5 days post infection (dpi) with aspirin (ASA) increased mortality (2-fold) and parasitemia (12-fold). However, there were no differences regarding histopathology or cardiac structure or function. Delayed treatment with ASA (20 mg/kg) beginning 60 dpi did not increase parasitemia or mortality but improved ejection fraction. ASA treatment diminished the profile of parasite-and host-derived circulating prostaglandins in infected mice. To distinguish the effects of ASA on the parasite and host bio-synthetic pathways we infected cyclooxygenase-1 (COX-1) null mice with the Brazil-strain of T. cruzi. Infected COX-1 null mice displayed a reduction in circulating levels of thromboxane (TX)A(2) and prostaglandin (PG)F(2 alpha). Parasitemia was increased in COX-1 null mice compared with parasitemia and mortality in ASA-treated infected mice indicating the effects of ASA on mortality potentially had little to do with inhibition of prostaglandin metabolism. Expression of SOCS-2 was enhanced, and TRAF6 and TNF alpha reduced, in the spleens of infected ASA-treated mice. Ablation of the initial innate response to infection may cause the increased mortality in ASA-treated mice as the host likely succumbs more quickly without the initiation of the ""cytokine storm'' during acute infection. We conclude that ASA, through both COX inhibition and other ""off-target'' effects, modulates the progression of acute and chronic Chagas disease. Thus, eicosanoids present during acute infection may act as immunomodulators aiding the transition to and maintenance of the chronic phase of the disease. A deeper understanding of the mechanism of ASA action may provide clues to the differences between host response in the acute and chronic T. cruzi infection.
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Objective: To analyze anteroposterior soft tissue facial parameters for a sample of white Brazilian adults and to compare these measurements with the values proposed for white North American adults. Materials and Methods: Facial profile photographs were taken of 59 white Brazilians (30 men and 29 women) with normal occlusions and balanced faces with ages ranging from 18 to 30 years. The independent Student's t-test (P < .05) was used to compare the soft tissue parameters of the Brazilians with those of the North Americans. Results: White Brazilian women presented a less protruded face compared with white American women except for the glabella region. White Brazilian women showed a smaller nasal projection, less protruded upper and lower lips, a more obtuse nasolabial angle, and a smaller projection of the B' point and chin than white American women. Conversely, the two male groups demonstrated less evident soft tissue profile differences, with the exception of the nose projection, which was smaller in white Brazilian men than in white American men. Conclusions: A universal standard of facial esthetic is not applicable to diverse white populations. Differences regarding the soft tissue profile features were found between white Brazilians and white Americans. These differences should be considered in the orthodontic/orthognathic surgery diagnosis and treatment plan for white Brazilians together with the patient's individual opinion and perception of beauty.
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It is shown that, for accretion disks, the height scale is a constant whenever hydrostatic equilibrium and the subsonic turbulence regime hold in the disk. In order to have a variable height scale, processes are needed that contribute an extra term to the continuity equation. This contribution makes the viscosity parameter much greater in the outer region and much smaller in the inner region. Under these circumstances, turbulence is the presumable source of viscosity in the disk.
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We discuss the dynamics of the Universe within the framework of the massive graviton cold dark matter scenario (MGCDM) in which gravitons are geometrically treated as massive particles. In this modified gravity theory, the main effect of the gravitons is to alter the density evolution of the cold dark matter component in such a way that the Universe evolves to an accelerating expanding regime, as presently observed. Tight constraints on the main cosmological parameters of the MGCDM model are derived by performing a joint likelihood analysis involving the recent supernovae type Ia data, the cosmic microwave background shift parameter, and the baryonic acoustic oscillations as traced by the Sloan Digital Sky Survey red luminous galaxies. The linear evolution of small density fluctuations is also analyzed in detail. It is found that the growth factor of the MGCDM model is slightly different (similar to 1-4%) from the one provided by the conventional flat Lambda CDM cosmology. The growth rate of clustering predicted by MGCDM and Lambda CDM models are confronted to the observations and the corresponding best fit values of the growth index (gamma) are also determined. By using the expectations of realistic future x-ray and Sunyaev-Zeldovich cluster surveys we derive the dark matter halo mass function and the corresponding redshift distribution of cluster-size halos for the MGCDM model. Finally, we also show that the Hubble flow differences between the MGCDM and the Lambda CDM models provide a halo redshift distribution departing significantly from the those predicted by other dark energy models. These results suggest that the MGCDM model can observationally be distinguished from Lambda CDM and also from a large number of dark energy models recently proposed in the literature.
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Aims. This work investigates the properties (metallicity and kinematics) and interfaces of the Galactic thick disc as a function of height above the Galactic plane. The main aim is to study the thick disc in a place where it is the main component of the sample. Methods. We take advantage of former astrometric work in two fields of several square degrees in which accurate proper motions were measured down to V-magnitudes of 18.5 in two directions, one near the north galactic pole and the other at a galactic latitude of 46 degrees and galactic longitude near 0 degrees. Spectroscopic observations have been acquired in these two fields for a total of about 400 stars down to magnitude 18.0, at spectral resolutions of 3.5 to 6.25 angstrom. The spectra have been analysed with the code ETOILE, comparing the target stellar spectra with a grid of 1400 reference stellar spectra. This comparison allowed us to derive the parameters effective temperature, gravity, [Fe/H] and absolute magnitude for each target star. Results. The Metallicity Distribution Function (MDF) of the thin-thick-disc-halo system is derived for several height intervals between 0 and 5 kpc above the Galactic plane. The MDFs show a decrease of the ratio of the thin to thick disc stars between the first and second kilo-parsec. This is consistent with the classical modelling of the vertical density profile of the disc with 2 populations with different scale heights. A vertical metallicity gradient, partial derivative[Fe/H]/partial derivative z = -0.068 +/- 0.009 dex kpc(-1), is observed in the thick disc. It is discussed in terms of scenarios of formation of the thick disc.
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Aims. An analytical solution for the discrepancy between observed core-like profiles and predicted cusp profiles in dark matter halos is studied. Methods. We calculate the distribution function for Navarro-Frenk-White halos and extract energy from the distribution, taking into account the effects of baryonic physics processes. Results. We show with a simple argument that we can reproduce the evolution of a cusp to a flat density profile by a decrease of the initial potential energy.