Ventilator-Associated Pneumonia and PaO2/FIO2 Diagnostic Accuracy: Changing the Paradigm?

BACKGROUND: Ventilator-associated pneumonia (VAP) is associated to longer stay and poor outcomes. Lacking definitive diagnostic criteria, worsening gas exchange assessed by PaO2/FIO2 ≤ 240 in mmHg has been proposed as one of the diagnostic criteria for VAP. We aim to assess the adequacy of PaO2/FIO2 ≤ 240 to diagnose VAP. METHODS: Prospective observational study in 255 consecutive patients with suspected VAP, clustered according to PaO2/FIO2 ≤ 240 vs. > 240 at pneumonia onset. The primary analysis was the association between PaO2/FIO2 ≤ 240 and quantitative microbiologic confirmation of pneumonia, the most reliable diagnostic gold-standard. RESULTS: Mean PaO2/FIO2 at VAP onset was 195 ± 82; 171 (67%) cases had PaO2/FIO2 ≤ 240. Patients with PaO2/FIO2 ≤ 240 had a lower APACHE-II score at ICU admission; however, at pneumonia onset they had higher CPIS, SOFA score, acute respiratory distress syndrome criteria and incidence of shock, and less microbiological confirmation of pneumonia (117, 69% vs. 71, 85%, p = 0.008), compared to patients with PaO2/FIO2 > 240. In multivariate logistic regression, PaO2/FIO2 ≤ 240 was independently associated with less microbiological confirmation (adjusted odds-ratio 0.37, 95% confidence interval 0.15-0.89, p = 0.027). The association between PaO2/FIO2 and microbiological confirmation of VAP was poor, with an area under the ROC curve 0.645. Initial non-response to treatment and length of stay were similar between both groups, while hospital mortality was higher in patients with PaO2/FIO2 ≤ 240. CONCLUSION: Adding PaO2/FIO2 ratio ≤ 240 to the clinical and radiographic criteria does not help in the diagnosis of VAP. PaO2/FIO2 ratio > 240 does not exclude this infection. Using this threshold may underestimate the incidence of VAP.info:eu-repo/semantics/publishedVersio

Transition from endemic behavior to eradication of malaria due to combined drug therapies: an agent-model approach

We introduce an agent-based model describing a susceptible-infectious-susceptible (SIS) system of humans and mosquitoes to predict malaria epidemiological scenarios in realistic biological conditions. Emphasis is given to the transition from endemic behavior to eradication of malaria transmission induced by combined drug therapies acting on both the gametocytemia reduction and on the selective mosquito mortality during parasite development in the mosquito. Our mathematical framework enables to uncover the critical values of the parameters characterizing the effect of each drug therapy. Moreover, our results provide quantitative evidence of what is empirically known: interventions combining gametocytemia reduction through the use of gametocidal drugs, with the selective action of ivermectin during parasite development in the mosquito, may actively promote disease eradication in the long run. In the agent model, the main properties of human-mosquito interactions are implemented as parameters and the model is validated by comparing simulations with real data of malaria incidence collected in the endemic malaria region of Chimoio in Mozambique. Finally, we discuss our findings in light of current drug administration strategies for malaria prevention, that may interfere with human-to-mosquito transmission process.Comment: 12 pages, 6 figure

Kounis Syndrome Associated With Selective Anaphylaxis to Cefazolin.

info:eu-repo/semantics/publishedVersio

"Volatility Models of Currency Futures in Developed and Emerging Markets"

This paper examines volatility models of currency futures contracts for three developed markets and two emerging markets. For each contract, standard models of the Unbiased Expectations Hypothesis (UEH) and Cost-of-Carry hypothesis (COC) are extended to derive volatility models corresponding to each of the two standard approaches. Each volatility model is formulated as a system of individual equations for the conditional variances of futures returns, spot returns and the domestic risk-free interest rate. The empirical results suggest that the conditional volatility of futures return for emerging markets is significant in explaining the conditional volatility of returns in the underlying spot market. For developed markets, however, the conditional volatility of the spot returns is significant in explaining the conditional volatility of futures returns. Moreover, it is found that the domestic risk-free interest rate has little impact on the conditional variances of the futures, spot and domestic risk-free interest rates.

Improving analysis of meta-omics data with the MOSCA framework

Introduction: Meta-omics is an emergent field of research with many resources available in the form of databases and software. The information stored in databases is not always easily accessible, and software tools for meta-omics are often difficult to utilize. In this work, we present Meta-Omics Software for Community Analysis (MOSCA), a software framework that implements pipelines for the integrated analysis of metagenomics (MG), metatranscriptomics (MT) and metaproteomics (MP) data. This framework integrates tools allowing access to databases, handling of data and a complete workflow for meta-omics data analysis. Methodology and results: MOSCA was developed in Python 3, takes as input raw files obtained from Next-generation sequencing (in FastQ format), and from mass spectrometry (mass spectra in vendor or peak-picked formats), and integrates several tools for MG, MT and MP analysis. These tools are connected through their inputs/outputs by snakemake, in a fully automated workflow. MG analysis starts with preprocessing of sequencing reads, which automatically configures Trimmomatic to remove adapters and low-quality reads based on FastQC quality reports, and SortMeRNA for rRNA reads removal. Assembly can be performed with MetaSPAdes or Megahit and is followed by binning with MaxBin2 and CheckM for quality check. Genes are identified with FragGeneScan and are annotated with both UPIMAPI (homology-based annotation) and reCOGnizer (domain-based annotation), with reference to UniProt KB and eight databases included in the Conserved Domains Database, respectively. Bowtie2 is used to align reads to metagenomes. Protein identification and quantification can be performed with either SearchCLI coupled to PeptideShaker (performing peptide-to-spectrum matching and spectra count) or using MaxQuant (with quantification at the MS1 level). Differential gene expression analysis is performed with DESeq2, and heatmaps, volcano plots and PCA plots are generated. The expressed enzymes are plotted into hundreds of KEGG metabolic maps with the tool KEGGCharter, showing the metabolic functions that are differentially expressed and the taxonomic assignment. Tables, heatmaps and other representations obtained with MOSCA provide an interactive, accessible and comprehensive representation of the information obtained from MG, MT and MP analyses. Conclusions: MOSCA performs automatic analyses of MG, MT and MP datasets, integrating over 20 tools to obtain a comprehensive and easy to understand representation of microbial activity in different processes and conditions.info:eu-repo/semantics/publishedVersio

Bronquiolite: Avanços Recentes

A bronquiolite e a infecção respiratória aguda das vias aéreas inferiores mais frequente em criançascom idade inferior a 24 meses, responsável por morbimortalidade significativa, incluindo complicações frequentes na fase aguda e a longo prazo. A heterogeneidade da abordagem desta patologia e a dificuldade em reduzir o seu peso nos indices de saúde pública, vem motivando investigação contínua e legitimou a publicação recente (2006) pela Academia Americana de Pediatria (AAP) de normas de actuação, chamando-se a atenção para os resultados de uma metanálise realizada pela Cochrane Collaboration e para a existência de diversos fenotipos de apresentação c1ínica.Os autores abordam alguns aspectos epidemiológicos, c1ínicos (nomeadamente as complicações) e, sobretudo, de terapêutica, com base em estudos recentes, elaborando uma proposta concretade actuação

Incidence of ventilator associated pneumonia in tracheostomised and non tracheostomised patients

Background: Pneumonia is the most common hospital acquired infection in the intensive care unit. One of the causes for hospital acquired pneumonia is ventilator associated pneumonia. Tracheostomy is known to prevent occurrence of ventilator associated pneumonia as it decreases the respiratory dead space, assists in better clearance of secretions and prevents chances of aspiration. Generally, tracheostomy is done after 2 weeks of endotracheal intubation to prevent tracheal complications. The aim of this study is to identify the incidence of ventilator associated pneumonia in tracheostomised and non tracheostomised patients and to see if early tracheostomy can prevent development of ventilator associated pneumonia.Methods: The study was conducted at a tertiary care hospital during a period of four years. 100 patients who were on mechanical ventilation for more than 7 days where taken up for the study. APACHE 4 scoring system was used. The incidence of Ventilator associated pneumonia in tracheostomised and non tracheostomised patients was studied.Results: In our study the total incidence of VAP was 44 %. In our study out of the 42 patients who had undergone tracheostomy 13 (30.95%) patients had ventilator associated pneumonia. Among the non-tracheostomised patients 31 (53.44%) out of 58 patients developed ventilator associated pneumonia. In our study the incidence of ventilator associated pneumonia was much lesser (12%) in patients who underwent tracheostomy in the period 7 to 10 days after mechanical ventilation, whereas in those who underwent tracheostomy after 11 days incidence of ventilator associated pneumonia was much higher.Conclusions: Our study showed that the incidence of ventilator associated pneumonia was much higher among non tracheostomised patients compared to patients who underwent tracheostomy. Hence patients undergoing earlier tracheostomy had a clear advantage than those undergoing tracheostomy late or non tracheostomised patients in preventing ventilator associated pneumonia

Novedades nomenclaturales en el género "Holcus" (Poaceae).

Nomenclatural novelties in the genus Holcus (Poaceae)Palabras clave. Nomenclatura, Holcus, Poaceae.Key words. Nomenclature, Holcus, Poaceae

Cardiovascular changes in patients presenting with vertigo

Background: The term dizziness often used to refer to a host of complaints which present in a similar manner. Of these vertigo is the most common. A thorough knowledge of cardiovascular changes that occur in subjects presenting with peripheral vertigo will help the treating medical practioner to promptly identify the cause of symptoms and prevent any confusion that may alter the course of treatment. The aim of this study to identify the changes in cardiovascular parameters that occur in patients with vertigo.Methods: Study was conducted at a tertiary care hospital during a period of two years during which 100 subjects where studied. Of these 50 where healthy adults which was taken as control group. Remaining 50 subjects where those who were admitted to hospital with a diagnosis of peripheral vertigo and termed as case group. Cardiovascular parameters where accessed in terms of pulse rate, rhythm, blood pressure and ECG Recordings among both the groups taken in static position and with 30 degree head tilt backwards and 45 degree angulation on either sides as is done during Dix-Hallpike’s maneuver immediately, after 3 minutes and 10 minutes of positioning the patient.Results: The study showed that there is no significant change in cardiovascular parameters in patients with vertigo when compared with healthy individuals in static position. Immediately following change in position of head there is sudden fall in pulse as well as blood pressure which then gradually comes back to baseline levels in healthy individuals. When there is a labyrinthine dysfunction in those who have hyper active labyrinth the pulse rate and Blood pressure increases sharply immediately after change in position then gradually comes back to baseline level. In hypo active labyrinth the pulse rate and blood pressure falls marginally compared to normal individuals and in dead labyrinths there is a significant fall in pulse rate and blood pressure immediately following change in position which then gradually reverts back to normal.Conclusions: From our study it is quite clear that there are considerable changes in cardiac parameters in patients presenting vertigo which should be kept in mind while evaluating the patients to prevent misdiagnosis. The study also proves a close coordination between vestibular system and central cardiovascular regulatory mechanisms during positional changes to maintain hemodynamic stability.