198 research outputs found
Human myocardial protein pattern reveals cardiac diseases
Proteomic profiles of myocardial tissue in two different etiologies of heart failure were investigated using high performance liquid chromatography (HPLC)/Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Right atrial appendages from 10 patients with hemodynamically significant isolated aortic valve disease and from 10 patients with isolated symptomatic coronary heart disease were collected during elective cardiac surgery. As presented in an earlier study by our group (Baykut et al., 2006), both disease forms showed clearly different pattern distribution characteristics. Interesting enough, the classification patterns could be used for correctly sorting unknown test samples in their correct categories. However, in order to fully exploit and also validate these findings there is a definite need for unambiguous identification of the differences between different etiologies at molecular level. In this study, samples representative for the aortic valve disease and coronary heart disease were prepared, tryptically digested, and analyzed using an FT-ICR MS that allowed collision-induced dissociation (CID) of selected classifier masses. By using the fragment spectra, proteins were identified by database searches. For comparison and further validation, classifier masses were also fragmented and analyzed using HPLC-/Matrix-assisted laser desorption ionization (MALDI) time-of-flight/time-of-flight (TOF/TOF) mass spectrometry. Desmin and lumican precursor were examples of proteins found in aortic samples at higher abundances than in coronary samples. Similarly, adenylate kinase isoenzyme was found in coronary samples at a higher abundance. The described methodology could also be feasible in search for specific biomarkers in plasma or serum for diagnostic purposes
Mechanical ventilation worsens abdominal edema and inflammation in porcine endotoxemia
INTRODUCTION: We hypothesized that mechanical ventilation per se increases abdominal edema and inflammation in sepsis and tested this in experimental endotoxemia. METHODS: Thirty anesthetized piglets were allocated to one of five groups: healthy control pigs breathing spontaneously with continuous positive pressure of 5 cm H(2)O or mechanically ventilated with positive end-expiratory pressure of 5 cm H(2)O, and endotoxemic piglets during mechanical ventilation for 2.5 hours and then continued on mechanical ventilation with positive end-expiratory pressure of either 5 or 15 cm H(2)O or switched to spontaneous breathing with continuous positive pressure of 5 cm H(2)O for another 2.5 hours. Abdominal edema formation was estimated by isotope technique, and inflammatory markers were measured in liver, intestine, lung, and plasma. RESULTS: Healthy controls: 5 hours of spontaneous breathing did not increase abdominal fluid, whereas mechanical ventilation did (Normalized Index increased from 1.0 to 1.6; 1 to 3.3 (median and range, P < 0.05)). Endotoxemic animals: Normalized Index increased almost sixfold after 5 hours of mechanical ventilation (5.9; 4.9 to 6.9; P < 0.05) with twofold increase from 2.5 to 5 hours whether positive end-expiratory pressure was 5 or 15, but only by 40% with spontaneous breathing (P < 0.05 versus positive end-expiratory pressure of 5 or 15 cm H(2)O). Tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in intestine and liver were 2 to 3 times higher with mechanical ventilation than during spontaneous breathing (P < 0.05) but similar in plasma and lung. Abdominal edema formation and TNF-α in intestine correlated inversely with abdominal perfusion pressure. CONCLUSIONS: Mechanical ventilation with positive end-expiratory pressure increases abdominal edema and inflammation in intestine and liver in experimental endotoxemia by increasing systemic capillary leakage and impeding abdominal lymph drainage
Combining Actor Network Theory and Genre Theory to Understand the Evolution of Digital Genres
In this paper we argue that a combination of Actor-Network Theory (ANT) and Genre Theory can constitute a theoretical framework for understanding how digital genres evolve.Genre theory states that genres evolve over time through reciprocal interaction between institutionalized practices and individual action; that they develop from actors’ responses to recurrent situations, and are shaped around characteristics as content, form, functionality and purpose. Genres emerge out of practice and at the same time they shape that practice. While genre theory can describe the characteristics of a genre, it cannot handle the processof how a genre is formed and what powers and forces are involved in this shaping process. In order to address this problem, several authors have incorporated structuration theory into genre analysis. However, structuration theory can only catch these constitutional processes of genre in a very broad manner. As a genre is evolving and stabilizing over time in interplay with different actors, it goes beyond what is possible to explain only by means ofstructuration theory. Instead, ANT could work as a tool to capture the process of how a genre takes form in negotiations with different stakeholders. In this paper we discuss how genre theory and ANT can be combined in a framework for analyzing emerging genres. We applythis theoretical framework on an e-newspaper project that embodies a new genre in the making. We will here show how evolving genre characteristics are developed, formed andstabilized in a negotiation and struggle between the involved actors when they translate their interests in ways that finally are resulting in a new genre
Development and Evaluation of a Sensitive PCR-ELISA System for Detection of Schistosoma Infection in Feces
Schistosomiasis is a neglected disease caused by worms of the genus Schistosoma. The transmission cycle requires contamination of bodies of water by parasite eggs present in excreta, specific snails as intermediate hosts and human contact with water. Fortunately, relatively safe and easily administrable drugs are available and, as the outcome of repeated treatment, a reduction of severe clinical forms and a decrease in the number of infected persons has been reported in endemic areas. The routine method for diagnosis is the microscopic examination but it fails when there are few eggs in the feces, as usually occurs in treated but noncured persons or in areas with low levels of transmission. This study reports the development of the PCR-ELISA system for the detection of Schistosoma DNA in human feces as an alternative approach to diagnose light infections. The system permits the enzymatic amplification of a specific region of the DNA from minute amounts of parasite material. Using the proposed PCR-ELISA approach for the diagnosis of a population in an endemic area in Brazil, 30% were found to be infected, as compared with the 18% found by microscopic fecal examination. Although the technique requires a complex laboratory infrastructure and specific funding it may be used by control programs targeting the elimination of schistosomiasis
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