356 research outputs found

    Síndrome de Stevens-Johnson. Apresentação de Caso Clínico

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    Introdução: A Síndrome de Stevens-Johnson (SSJ) é uma doença mucocutânea rara e potencialmente fatal, mais frequente no sexo masculino, cuja incidência aumenta com a idade e em determinados grupos de risco. A SSJ e a Necrólise Tóxica Epidérmica (NET) são duas entidades da mesma doença, com severidade diferente. A etiologia não é clara, mas pensa-se que se deva maioritariamente a reacções adversas a fármacos. Caso clínico: Um jovem de 17 anos de idade, sem antecedentes pessoais relevantes, foi observado no Serviço de Urgência por surgimento de lesões maculopapulares, com 3 dias de evolução, dispersas pela face, cavidade oral, tronco e extremidades, com prostração e taquicardia. Foi internado com o diagnóstico de SSJ. Discussão e Conclusões: O SSJ e a NET têm grande morbilidade e considerável mortalidade. O rápido reconhecimento desta identidade, com a remoção do fármaco desencadeador é essencial. A perda da função de barreira da pele, com a consequente alteração da homeostasia, implica muitas vezes a manutenção da terapêutica de suporte em Unidades de Cuidados Intensivos ou de Queimados.info:eu-repo/semantics/publishedVersio

    The frequency of CD127low expressing CD4+CD25high T regulatory cells is inversely correlated with human T lymphotrophic virus type-1 (HTLV-1) proviral load in HTLV-1-infection and HTLV-1-associated myelopathy/tropical spastic paraparesis

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    <p>Abstract</p> <p>Background</p> <p>CD4<sup>+</sup>CD25<sup>high </sup>regulatory T (T<sub>Reg</sub>) cells modulate antigen-specific T cell responses, and can suppress anti-viral immunity. In HTLV-1 infection, a selective decrease in the function of T<sub>Reg </sub>cell mediated HTLV-1-tax inhibition of FOXP3 expression has been described. The purpose of this study was to assess the frequency and phenotype of T<sub>Reg </sub>cells in HTLV-1 asymptomatic carriers and in HTLV-1-associated neurological disease (HAM/TSP) patients, and to correlate with measures of T cell activation.</p> <p>Results</p> <p>We were able to confirm that HTLV-I drives activation, spontaneous IFNγ production, and proliferation of CD4+ T cells. We also observed a significantly lower proportion of CTLA-4<sup>+ </sup>T<sub>Reg </sub>cells (CD4<sup>+</sup>CD25<sup>high </sup>T cells) in subjects with HAM/TSP patients compared to healthy controls. Ki-67 expression was negatively correlated to the frequency of CTLA-4<sup>+ </sup>T<sub>Reg </sub>cells in HAM/TSP only, although Ki-67 expression was inversely correlated with the percentage of CD127<sup>low </sup>T<sub>Reg </sub>cells in healthy control subjects. Finally, the proportion of CD127<sup>low </sup>T<sub>Reg </sub>cells correlated inversely with HTLV-1 proviral load.</p> <p>Conclusion</p> <p>Taken together, the results suggest that T<sub>Reg </sub>cells may be subverted in HAM/TSP patients, which could explain the marked cellular activation, spontaneous cytokine production, and proliferation of CD4<sup>+ </sup>T cells, in particular those expressing the CD25<sup>high</sup>CD127<sup>low </sup>phenotype. T<sub>Reg </sub>cells represent a potential target for therapeutic intervention for patients with HTLV-1-related neurological diseases.</p

    Oldest Known Eucalyptus Macrofossils Are from South America

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    The evolutionary history of Eucalyptus and the eucalypts, the larger clade of seven genera including Eucalyptus that today have a natural distribution almost exclusively in Australasia, is poorly documented from the fossil record. Little physical evidence exists bearing on the ancient geographical distributions or morphologies of plants within the clade. Herein, we introduce fossil material of Eucalyptus from the early Eocene (ca. 51.9 Ma) Laguna del Hunco paleoflora of Chubut Province, Argentina; specimens include multiple leaves, infructescences, and dispersed capsules, several flower buds, and a single flower. Morphological similarities that relate the fossils to extant eucalypts include leaf shape, venation, and epidermal oil glands; infructescence structure; valvate capsulate fruits; and operculate flower buds. The presence of a staminophore scar on the fruits links them to Eucalyptus, and the presence of a transverse scar on the flower buds indicates a relationship to Eucalyptus subgenus Symphyomyrtus. Phylogenetic analyses of morphological data alone and combined with aligned sequence data from a prior study including 16 extant eucalypts, one outgroup, and a terminal representing the fossils indicate that the fossils are nested within Eucalyptus. These are the only illustrated Eucalyptus fossils that are definitively Eocene in age, and the only conclusively identified extant or fossil eucalypts naturally occurring outside of Australasia and adjacent Mindanao. Thus, these fossils indicate that the evolution of the eucalypt group is not constrained to a single region. Moreover, they strengthen the taxonomic connections between the Laguna del Hunco paleoflora and extant subtropical and tropical Australasia, one of the three major ecologic-geographic elements of the Laguna del Hunco paleoflora. The age and affinities of the fossils also indicate that Eucalyptus subgenus Symphyomyrtus is older than previously supposed. Paleoecological data indicate that the Patagonian Eucalyptus dominated volcanically disturbed areas adjacent to standing rainforest surrounding an Eocene caldera lake

    An experimental study of Quartets MaxCut and other supertree methods

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    <p>Abstract</p> <p>Background</p> <p>Supertree methods represent one of the major ways by which the Tree of Life can be estimated, but despite many recent algorithmic innovations, matrix representation with parsimony (MRP) remains the main algorithmic supertree method.</p> <p>Results</p> <p>We evaluated the performance of several supertree methods based upon the Quartets MaxCut (QMC) method of Snir and Rao and showed that two of these methods usually outperform MRP and five other supertree methods that we studied, under many realistic model conditions. However, the QMC-based methods have scalability issues that may limit their utility on large datasets. We also observed that taxon sampling impacted supertree accuracy, with poor results obtained when all of the source trees were only sparsely sampled. Finally, we showed that the popular optimality criterion of minimizing the total topological distance of the supertree to the source trees is only weakly correlated with supertree topological accuracy. Therefore evaluating supertree methods on biological datasets is problematic.</p> <p>Conclusions</p> <p>Our results show that supertree methods that improve upon MRP are possible, and that an effort should be made to produce scalable and robust implementations of the most accurate supertree methods. Also, because topological accuracy depends upon taxon sampling strategies, attempts to construct very large phylogenetic trees using supertree methods should consider the selection of source tree datasets, as well as supertree methods. Finally, since supertree topological error is only weakly correlated with the supertree's topological distance to its source trees, development and testing of supertree methods presents methodological challenges.</p

    Why media representations of corporations matter for public health policy : a scoping review

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    BACKGROUND: Media representations play a crucial role in informing public and policy opinions about the causes of, and solutions to, ill-health. This paper reviews studies analysing media coverage of non-communicable disease (NCD) debates, focusing on how the industries marketing commodities that increase NCD risk are represented. METHODS: A scoping review identified 61 studies providing information on media representations of NCD risks, NCD policies and tobacco, alcohol, processed food and soft drinks industries. The data were narratively synthesized to describe the sample, media depictions of industries, and corporate and public health attempts to frame the media debates. RESULTS: The findings indicate that: (i) the limited research that has been undertaken is dominated by a focus on tobacco; (ii) comparative research across industries/risk-factors is particularly lacking; and (iii) coverage tends to be dominated by two contrasting frames and focuses either on individual responsibilities ('market justice' frames, often promoted by commercial stakeholders) or on the need for population-level interventions ('social justice' frames, frequently advanced by public health advocates). CONCLUSIONS: Establishing the underlying frameworks is crucial for the analysis of media representation of corporations, as they reflect the strategies that respective actors use to influence public health debates and decision making. The potential utility of media research lies in the insights that it can provide for public health policy advocates about successful framing of public health messages and strategies to counter frames that undermine public health goals. A better understanding of current media debates is of paramount importance to improving global health

    A previously unidentified Chorioptes species infesting outer ear canals of moose (Alces alces): characterization of the mite and the pathology of infestation

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    <p>Abstract</p> <p>Background</p> <p>During the past decade, <it>Chorioptes </it>mites occupying the outer ear canals have been a common finding at routine necropsies of moose (<it>Alces alces</it>) in Sweden, but neither the taxonomy of the mites nor lesions from the infestation have been investigated. In this study, the mites are characterized by morphological and molecular techniques, and the histopathology of the skin of the outer ear canal is described.</p> <p>Methods</p> <p>External auditory meatuses from 53 necropsied moose were examined for the presence of <it>Chorioptes</it>, and samples from outer ear canals were taken for histopathological and microbiological examination. A proportion of the mites from each moose was identified to species. The DNA was extracted from mites from three moose, and their ITS-2 sequences were determined; these sequences were compared phylogenetically to sequences from other <it>Chorioptes </it>taxa.</p> <p>Results</p> <p><it>Chorioptes </it>mites were found in 43 (81%) of the 53 moose. The mites had morphological and genetic characteristics distinct from those of <it>C. texanus </it>and <it>C. bovis</it>, the two species generally accepted within the genus. Morphology also did not argue for a diagnosis as <it>C. crewei</it>, <it>C. mydaus </it>or <it>C. panda</it>. On histopathology, lesions were characterized by a hyperplastic perivascular to interstitial dermatitis with epidermal hyperkeratosis and crust formation. Dermal inflammatory infiltrates were composed of mixed T- and B-lymphocytes, plasma cells and macrophages, whereas eosinophils were notably uncommon. <it>Staphylococcus aureus </it>was grown from the infested epidermis of five of 14 examined moose.</p> <p>Conclusion</p> <p><it>Chorioptes </it>mite infestation was frequently detected in the outer ear canals of moose in Sweden. The mites were evidently pathogenic, being associated with inflammatory lesions of the external auditory meatus. Our studies indicate infestations with a previously undescribed <it>Chorioptes </it>species.</p

    A New Saurolophine Dinosaur from the Latest Cretaceous of Far Eastern Russia

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    Background: Four main dinosaur sites have been investigated in latest Cretaceous deposits from the Amur/Heilongjiang Region: Jiayin and Wulaga in China (Yuliangze Formation), Blagoveschensk and Kundur in Russia (Udurchukan Formation). More than 90% of the bones discovered in these localities belong to hollow-crested lambeosaurine saurolophids, but flat-headed saurolophines are also represented: Kerberosaurus manakini at Blagoveschensk and Wulagasaurus dongi at Wulaga. Methodology/Principal Findings: Herein we describe a new saurolophine dinosaur, Kundurosaurus nagornyi gen. et sp. nov. from the Udurchukan Formation (Maastrichtian) of Kundur, represented by disarticulated cranial and postcranial material. This new taxon is diagnosed by four autapomorphies. Conclusions/Significance: A phylogenetic analysis of saurolophines indicates that Kundurosaurus nagornyi is nested within a rather robust clade including Edmontosaurus spp. Saurolophus spp. and Prosaurolophus maximus, possibly as a sister-taxon for Kerberosaurus manakini also from the Udurchukan Formation of Far Eastern Russia. The high diversity and mosaic distribution of Maastrichtian hadrosaurid faunas in the Amur-Heilongjiang region are the result of a complex palaeogeographical history and imply that many independent hadrosaurid lineages dispersed without any problem between western America and eastern Asia at the end of the Cretaceous. © 2012 Godefroit et al.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

    Large-Scale Phylogenetic Analysis of Emerging Infectious Diseases

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    Microorganisms that cause infectious diseases present critical issues of national security, public health, and economic welfare.  For example, in recent years, highly pathogenic strains of avian influenza have emerged in Asia, spread through Eastern Europe and threaten to become pandemic. As demonstrated by the coordinated response to Severe Acute Respiratory Syndrome (SARS) and influenza, agents of infectious disease are being addressed via large-scale genomic sequencing.  The goal of genomic sequencing projects are to rapidly put large amounts of data in the public domain to accelerate research on disease surveillance, treatment, and prevention. However, our ability to derive information from large comparative genomic datasets lags far behind acquisition.  Here we review the computational challenges of comparative genomic analyses, specifically sequence alignment and reconstruction of phylogenetic trees.  We present novel analytical results on from two important infectious diseases, Severe Acute Respiratory Syndrome (SARS) and influenza.SARS and influenza have similarities and important differences both as biological and comparative genomic analysis problems.  Influenza viruses (Orthymxyoviridae) are RNA based.  Current evidence indicates that influenza viruses originate in aquatic birds from wild populations. Influenza has been studied for decades via well-coordinated international efforts.  These efforts center on surveillance via antibody characterization of the hemagglutinin (HA) and neuraminidase (N) proteins of the circulating strains to inform vaccine design. However we still do not have a clear understanding of: 1) various transmission pathways such as the role of intermediate hosts such as swine and domestic birds and 2) the key mutation and genomic recombination events that underlie periodic pandemics of influenza.  In the past 30 years, sequence data from HA and N loci has become an important data type. In the past year, full genomic data has become prominent.  These data present exciting opportunities to address unanswered questions in influenza pandemics.SARS is caused by a previously unrecognized lineage of coronavirus, SARS-CoV, which like influenza has an RNA based genome.  Although SARS-CoV is widely believed to have originated in animals there remains disagreement over the candidate animal source that lead to the original outbreak of SARS.  In contrast to the long history of the study of influenza, SARS was only recognized in late 2002 and the virus that causes SARS has been documented primarily by genomic sequencing.In the past, most studies of influenza were performed on a limited number of isolates and genes suited to a particular problem.  Major goals in science today are to understand emerging diseases in broad geographic, environmental, societal, biological, and genomic contexts. Synthesizing diverse information brought together by various researchers is important to find out what can be done to prevent future outbreaks {JON03}.  Thus comprehensive means to organize and analyze large amounts of diverse information are critical.  For example, the relationships of isolates and patterns of genomic change observed in large datasets might not be consistent with hypotheses formed on partial data.  Moreover when researchers rely on partial datasets, they restrict the range of possible discoveries.Phylogenetics is well suited to the complex task of understanding emerging infectious disease. Phylogenetic analyses can test many hypotheses by comparing diverse isolates collected from various hosts, environments, and points in time and organizing these data into various evolutionary scenarios.  The products of a phylogenetic analysis are a graphical tree of ancestor-descendent relationships and an inferred summary of mutations, recombination events, host shifts, geographic, and temporal spread of the viruses.  However, this synthesis comes at a price.  The cost of computation of phylogenetic analysis expands combinatorially as the number of isolates considered increases. Thus, large datasets like those currently produced are commonly considered intractable.  We address this problem with synergistic development of heuristics tree search strategies and parallel computing.Fil: Janies, D.. Ohio State University; Estados UnidosFil: Pol, Diego. Ohio State University; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

    Characterization of the "deqi" response in acupuncture

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    <p>Abstract</p> <p>Background</p> <p>Acupuncture stimulation elicits <it>deqi</it>, a composite of unique sensations that is essential for clinical efficacy according to traditional Chinese medicine (TCM). There is lack of adequate experimental data to indicate what sensations comprise <it>deqi</it>, their prevalence and intensity, their relationship to acupoints, how they compare with conventional somatosensory or noxious response. The objective of this study is to provide scientific evidence on these issues and to characterize the nature of the <it>deqi phenomenon </it>in terms of the prevalence of sensations as well as the uniqueness of the sensations underlying the <it>deqi </it>experience.</p> <p>Methods</p> <p>Manual acupuncture was performed at LI4, ST36 and LV3 on the extremities in randomized order during fMRI in 42 acupuncture naïve healthy adult volunteers. Non-invasive tactile stimulation was delivered to the acupoints by gentle tapping with a von Frey monofilament prior to acupuncture to serve as a sensory control. At the end of each procedure, the subject was asked if each of the sensations listed in a questionnaire or any other sensations occurred during stimulation, and if present to rate its intensity on a numerical scale of 1–10. Statistical analysis including paired t-test, analysis of variance, Spearman's correlation and Fisher's exact test were performed to compare responses between acupuncture and sensory stimulation.</p> <p>Results</p> <p>The <it>deqi </it>response was elicited in 71% of the acupuncture procedures compared with 24% for tactile stimulation when thresholded at a minimum total score of 3 for all the sensations. The frequency and intensity of individual sensations were significantly higher in acupuncture. Among the sensations typically associated with <it>deqi</it>, aching, soreness and pressure were most common, followed by tingling, numbness, dull pain, heaviness, warmth, fullness and coolness. Sharp pain of brief duration that occurred in occasional subjects was regarded as inadvertent noxious stimulation. The most significant differences in the <it>deqi </it>sensations between acupuncture and tactile stimulation control were observed with aching, soreness, pressure and dull pain. Consistent with its prominent role in TCM, LI4 showed the most prominent response, the largest number of sensations as well as the most marked difference in the frequency and intensity of aching, soreness and dull pain between acupuncture and tactile stimulation control. Interestingly, the dull pain generally preceded or occurred in the absence of sharp pain in contrast to reports in the pain literature. An approach to summarize a sensation profile, called the <it>deqi composite</it>, is proposed and applied to explain differences in <it>deqi </it>among acupoints.</p> <p>Conclusion</p> <p>The complex pattern of sensations in the <it>deqi </it>response suggests involvement of a wide spectrum of myelinated and unmyelinated nerve fibers, particularly the slower conducting fibers in the tendinomuscular layers. The study provides scientific data on the characteristics of the <it>'deqi' </it>response in acupuncture and its association with distinct nerve fibers. The findings are clinically relevant and consistent with modern concepts in neurophysiology. They can provide a foundation for future studies on the <it>deqi </it>phenomenon.</p

    Cryptic Speciation in Brazilian Epiperipatus (Onychophora: Peripatidae) Reveals an Underestimated Diversity among the Peripatid Velvet Worms

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    Taxonomical studies of the neotropical Peripatidae (Onychophora, velvet worms) have proven difficult, due to intraspecific variation and uniformity of morphological characters across this onychophoran subgroup. We therefore used molecular approaches, in addition to morphological methods, to explore the diversity of Epiperipatus from the Minas Gerais State of Brazil.Our analyses revealed three new species. While Epiperipatus diadenoproctussp. nov. can be distinguished from E. adenocryptussp. nov. and E. paurognostussp. nov. based on morphology and specific nucleotide positions in the mitochondrial cytochrome c oxidase subunit I (COI) and small ribosomal subunit RNA gene sequences (12S rRNA), anatomical differences between the two latter species are not evident. However, our phylogenetic analyses of molecular data suggest that they are cryptic species, with high Bayesian posterior probabilities and bootstrap and Bremer support values for each species clade. The sister group relationship of E. adenocryptussp. nov. and E. paurognostussp. nov. in our analyses correlates with the remarkable morphological similarity of these two species. To assess the species status of the new species, we performed a statistical parsimony network analysis based on 582 base pairs of the COI gene in our specimens, with the connection probability set to 95%. Our findings revealed no connections between groups of haplotypes, which have been recognized as allopatric lineages in our phylogenetic analyses, thus supporting our suggestion that they are separate species.Our findings suggest high cryptic species diversity and endemism among the neotropical Peripatidae and demonstrate that the combination of morphological and molecular approaches is helpful for clarifying the taxonomy and species diversity of this apparently large and diverse onychophoran group
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