250 research outputs found
False-Positive Uptake on Radioiodine Whole-Body Scan Due to Bronchiectasis
info:eu-repo/semantics/publishedVersio
Leucodistrofia com Envolvimento do Tronco Cerebral e Medula Espinhal e Aumento de Lactato - Caso Clnico
Stable isotopes as ecological tracers: an efficient method for assessing the contribution of multiple sources to mixtures
Stable isotopes are increasingly being used as
tracers of ecological processes potentially providing relevant
information to environmental management issues. An application
of the methodology consists in relating the stable
isotopic composition of a sample mixture to that of sources.
The number of stable isotopes, however, is usually lower
than that of potential sources existing in an ecosystem, which
creates mathematical difficulties in correctly tracing sources.
We discuss a linear programming model which efficiently
derives information on the contribution of sources to mixtures
for any number of stable isotopes and any number of
sources by addressing multiple sources simultaneously. The
model identifies which sources are present in all, present in
a subset of the samples or absent from all samples simultaneously
and calculates minimum and maximum values of
each source in the mixtures. We illustrate the model using a
data set consisting of the isotopic signatures of different plant
sources ingested by primary consumers in tropical riverine
habitat in Asia. The model discussed may contribute to extend
the scope of stable isotopes methodology to a range
of new problems dealing with multiple sources and multiple
tracers. For instance, in food web studies, if particular
organic matter sources disappear or decrease in availability
(e.g. climate change scenarios) the model allows simulation
of alternative diets of the consumers providing potentially
relevant information for managers and decision makers
Global optimal eBURST analysis of multilocus typing data using a graphic matroid approach
<p>Abstract</p> <p>Background</p> <p>Multilocus Sequence Typing (MLST) is a frequently used typing method for the analysis of the clonal relationships among strains of several clinically relevant microbial species. MLST is based on the sequence of housekeeping genes that result in each strain having a distinct numerical allelic profile, which is abbreviated to a unique identifier: the sequence type (ST). The relatedness between two strains can then be inferred by the differences between allelic profiles. For a more comprehensive analysis of the possible patterns of evolutionary descent, a set of rules were proposed and implemented in the eBURST algorithm. These rules allow the division of a data set into several clusters of related strains, dubbed clonal complexes, by implementing a simple model of clonal expansion and diversification. Within each clonal complex, the rules identify which links between STs correspond to the most probable pattern of descent. However, the eBURST algorithm is not globally optimized, which can result in links, within the clonal complexes, that violate the rules proposed.</p> <p>Results</p> <p>Here, we present a globally optimized implementation of the eBURST algorithm – goeBURST. The search for a global optimal solution led to the formalization of the problem as a graphic matroid, for which greedy algorithms that provide an optimal solution exist. Several public data sets of MLST data were tested and differences between the two implementations were found and are discussed for five bacterial species: <it>Enterococcus faecium</it>, <it>Streptococcus pneumoniae</it>, <it>Burkholderia pseudomallei</it>, <it>Campylobacter jejuni </it>and <it>Neisseria spp.</it>. A novel feature implemented in goeBURST is the representation of the level of tiebreak rule reached before deciding if a link should be drawn, which can used to visually evaluate the reliability of the represented hypothetical pattern of descent.</p> <p>Conclusion</p> <p>goeBURST is a globally optimized implementation of the eBURST algorithm, that identifies alternative patterns of descent for several bacterial species. Furthermore, the algorithm can be applied to any multilocus typing data based on the number of differences between numeric profiles. A software implementation is available at <url>http://goeBURST.phyloviz.net</url>.</p
Psychosis Assessment in Early-Stage Parkinson's Disease: Comparing Parkinson's Psychosis Questionnaire with the Brief Psychiatric Rating Scale in a Portuguese Sample
Psychotic symptoms in Parkinson's disease (PD) are frequent, disabling, and an important prognostic factor. Thus, screening instruments for detecting psychosis in PD are needed. For this purpose, we applied the Parkinson's Psychosis Questionnaire (PPQ), a short structured questionnaire, which requires no specific training, along with the Brief Psychiatric Rating Scale, expanded version (BPRS-E), for rating general psychopathology, including psychotic symptoms.
We evaluated, in a cross-sectional study, a Portuguese sample of 36 early-stage PD patients (mean age of 73 years; mean duration of illness of 3.2 years). The PPQ total score correlated with the BPRS-E total score (0.359; P = 0.032) and with the BPRS-E-positive symptoms score (0.469; P = 0.004). The prevalence of psychosis (41.7%) was higher than expected. Sampling bias and detection of minor psychotic phenomena may have contributed to this result.
These findings suggest that the PPQ should be further evaluated as a feasible assessment for psychotic symptoms in PD
Assessment of a Large-Scale Unbiased Malignant Pleural Effusion Proteomics Study of a Real-Life Cohort
Background: Pleural effusion (PE) is common in advanced-stage lung cancer patients
and is related to poor prognosis. Identification of cancer cells is the standard method for the
diagnosis of a malignant PE (MPE). However, it only has moderate sensitivity. Thus, more sensitive
diagnostic tools are urgently needed. Methods: The present study aimed to discover potential protein
targets to distinguish malignant pleural effusion (MPE) from other non-malignant pathologies. We
have collected PE from 97 patients to explore PE proteomes by applying state-of-the-art liquid
chromatography-mass spectrometry (LC-MS) to identify potential biomarkers that correlate with
immunohistochemistry assessment of tumor biopsy or with survival data. Functional analyses
were performed to elucidate functional differences in PE proteins in malignant and benign samples.
Results were integrated into a clinical risk prediction model to identify likely malignant cases.
Sensitivity, specificity, and negative predictive value were calculated. Results: In total, 1689 individual
proteins were identified by MS-based proteomics analysis of the 97 PE samples, of which 35 were
diagnosed as malignant. A comparison between MPE and benign PE (BPE) identified 58 differential
regulated proteins after correction of the p-values for multiple testing. Furthermore, functional
analysis revealed an up-regulation of matrix intermediate filaments and cellular movement-related
proteins. Additionally, gene ontology analysis identified the involvement of metabolic pathways
such as glycolysis/gluconeogenesis, pyruvate metabolism and cysteine and methionine metabolism.
Conclusion: This study demonstrated a partial least squares regression model with an area under the
curve of 98 and an accuracy of 0.92 when evaluated on the holdout test data set. Furthermore, highly
significant survival markers were identified (e.g., PSME1 with a log-rank of 1.68 × 10−6
).info:eu-repo/semantics/publishedVersio
a consensus statement from the Portuguese Pulmonology Society
Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by a novel SARS-CoV-2 pathogen. Its capacity for human-to-human transmission through respiratory droplets, coupled with a high-level of population mobility, has resulted in a rapid dissemination worldwide. Healthcare workers have been particularly exposed to the risk of infection and represent a significant proportion of COVID-19 cases in the worst affected regions of Europe. Like other open airway procedures or aerosol-generating procedures, bronchoscopy poses a significant risk of spreading contaminated droplets, and medical workers must adapt the procedures to ensure safety of both patients and staff. Several recommendation documents were published at the beginning of the pandemic, but as the situation evolves, our thoughts should not only focus on the present, but should also reflect on how we are going to deal with the presence of the virus in the community until there is a vaccine or specific treatment available. It is in this sense that this document aims to guide interventional pulmonology throughout this period, providing a set of recommendations on how to perform bronchoscopy or pleural procedures safely and efficiently.proofpublishe
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