256 research outputs found

    Pathophysiological Mechanisms In Gaseous Therapies For Severe Malaria

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    Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Over 200 million people worldwide suffer from malaria every year, a disease that causes 584,000 deaths annually. In recent years, significant improvements have been achieved on the treatment of severe malaria, with intravenous artesunate proving superior to quinine. However, mortality remains high, at 8% in children and 15% in adults in clinical trials, and even worse in the case of cerebral malaria (18% and 30%, respectively). Moreover, some individuals who do not succumb to severe malaria present long-term cognitive deficits. These observations indicate that strategies focused only on parasite killing fail to prevent neurological complications and deaths associated with severe malaria, possibly because clinical complications are associated in part with a cerebrovascular dysfunction. Consequently, different adjunctive therapies aimed at modulating malaria pathophysiological processes are currently being tested. However, none of these therapies has shown unequivocal evidence in improving patient clinical status. Recently, key studies have shown that gaseous therapies based mainly on nitric oxide (NO), carbon monoxide (CO), and hyperbaric (pressurized) oxygen (HBO) alter vascular endothelium dysfunction and modulate the host immune response to infection. Considering gaseous administration as a promising adjunctive treatment against severe malaria cases, we review here the pathophysiological mechanisms and the immunological aspects of such therapies.844874882HHS \ National Institutes of Health (NIH) [AI118302-02]MCTI \ Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)Fabio Trindade Maranhao Costa [2012/16525-2]Fundacao de Amparo a Pesquisa do Estado do Rio de Janeiro (FAPERJ)Carvalho through a Cientista do Nosso Estado fellowshipConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

    Pathophysiological Mechanisms In Gaseous Therapies For Severe Malaria.

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    Over 200 million people worldwide suffer from malaria every year, a disease that causes 584,000 deaths annually. In recent years, significant improvements have been achieved on the treatment of severe malaria, with intravenous artesunate proving superior to quinine. However, mortality remains high at 8% in children and 15% in adults in clinical trials, and even worse in the case of cerebral malaria (18% and 30%, respectively). Moreover, some individuals who do not succumb to severe malaria present long-term cognitive deficits. These observations indicate that strategies focused only on parasite killing fail to prevent neurological complications and deaths associated with severe malaria, possibly because clinical complications are associated in part with a cerebrovascular dysfunction. Consequently, different adjunctive therapies aimed at modulating malaria pathophysiological processes are currently being tested. However, none of these therapies has shown unequivocal evidence in improving patients' clinical status. Recently, key studies have shown that gaseous therapies based mainly on nitric oxide (NO), carbon monoxide (CO) and hyperbaric (pressurized) oxygen (HBO) alter vascular endothelium dysfunction and modulate host immune response to infection. Considering gaseous administration as a promising adjunctive treatment against severe malaria cases, we review here the pathophysiological mechanisms and the immunological aspects of such therapies.8

    Circulating adrenomedullin in cirrhosis: relationship to hyperdynamic circulation

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    BACKGROUND/AIMS: Peripheral arterial vasodilation may be the key factor in the sodium and water retention of cirrhosis. The mechanism responsible for this vasodilation remains to be fully elucidated. Adrenomedullin is a novel peptide, highly expressed in cardiovascular tissues, with potent and long-lasting vasodilating activity. METHODS: The possible implication of adrenomedullin in the hemodynamic changes of cirrhosis has been investigated. We measured the plasma concentration of adrenomedullin in 20 cirrhotic patients and 11 healthy subjects. In addition, systemic, portal and renal hemodynamics, hormonal factors and renal function parameters were evaluated in the same patients. RESULTS: Circulating adrenomedullin was significantly higher in the group of patients with cirrhosis (72.1; 46-100 vs 21.6; 11-34 fmol/dl, respectively; p<0.02) and was directly correlated with the Pugh score (r: 0.6; p: 0.01), inversely correlated with the creatinine clearance (r: -0.6; p<0.01) and tended to inversely correlate with systemic vascular resistance index (r: -0.46; p: 0.07). There were no portal-peripheral differences in adrenomedullin levels. Transjugular intrahepatic portosystemic shunt insertion did not induce changes in the peripheral concentration of adrenomedullin, but baseline values of this hormone predicted the degree of hyperdynamic circulation after TIPS. CONCLUSIONS: Circulating adrenomedullin is increased in cirrhosis. These levels increase with the severity of the disease, especially in patients with hepatorenal syndrome. This peptide may contribute to vasodilation of cirrhosis

    Wound-up phase turbulence in the Complex Ginzburg-Landau equation

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    We consider phase turbulent regimes with nonzero winding number in the one-dimensional Complex Ginzburg-Landau equation. We find that phase turbulent states with winding number larger than a critical one are only transients and decay to states within a range of allowed winding numbers. The analogy with the Eckhaus instability for non-turbulent waves is stressed. The transition from phase to defect turbulence is interpreted as an ergodicity breaking transition which occurs when the range of allowed winding numbers vanishes. We explain the states reached at long times in terms of three basic states, namely quasiperiodic states, frozen turbulence states, and riding turbulence states. Justification and some insight into them is obtained from an analysis of a phase equation for nonzero winding number: rigidly moving solutions of this equation, which correspond to quasiperiodic and frozen turbulence states, are understood in terms of periodic and chaotic solutions of an associated system of ordinary differential equations. A short report of some of our results has been published in [Montagne et al., Phys. Rev. Lett. 77, 267 (1996)].Comment: 22 pages, 15 figures included. Uses subfigure.sty (included) and epsf.tex (not included). Related research in http://www.imedea.uib.es/Nonlinea

    Yet Another Ranking Function for Automatic Multiword Term Extraction

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    International audienceTerm extraction is an essential task in domain knowledge acquisition. We propose two new measures to extract multiword terms from a domain-specific text. The first measure is both linguistic and statistical based. The second measure is graph-based, allowing assessment of the importance of a multiword term of a domain. Existing measures often solve some problems related (but not completely) to term extraction, e.g., noise, silence, low frequency, large-corpora, complexity of the multiword term extraction process. Instead, we focus on managing the entire set of problems, e.g., detecting rare terms and overcoming the low frequency issue. We show that the two proposed measures outperform precision results previously reported for automatic multiword extraction by comparing them with the state-of-the-art reference measures

    Stillbirth at term: Does size really matter?

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    Placental dysfunction has a deleterious influence on fetal size and is associated with higher rates of perinatal morbidity and mortality. This association underpins the strategy of fetal size evaluation as a mechanism to identify placental dysfunction and prevent stillbirth. The optimal method of routine detection of small for gestational age (SGA) remains to be clarified with choices between estimation of symphyseal-fundal height versus routine third-trimester ultrasound, various formulae for fetal weight estimation by ultrasound, and the variable use of national, customized, or international fetal growth references. In addition to these controversies, the strategy for detecting SGA is further undermined by data demonstrating that the relationship between fetal size and adverse outcome weakens significantly with advancing gestation such that near term, the majority of stillbirths and adverse perinatal outcomes occur in normally sized fetuses. The use of maternal serum biochemical and Doppler parameters near term appears to be superior to fetal size in the identification of fetuses compromised by placental dysfunction and at increased risk of damage or demise. Multiparameter models and predictive algorithms using maternal risk factors, and biochemical and Doppler parameters have been developed, but need to be prospectively validated to demonstrate their effectiveness

    Identificación de términos a partir de enumeraciones sintagmáticas nominales: una aplicación al dominio médico

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    Partiendo de la hipótesis de que las enumeraciones sintagmáticas nominales (ESN) que se encuentran en los textos médicos se componen de términos específicos del dominio, presentamos un método de reconocimiento de dichas enumeraciones con el objetivo de contribuir a la extracción automática. La metodología se conforma de tres etapas: (i) reconocimiento de enumeraciones sintagmáticas nominales, aquí se utiliza exclusivamente información lingüística, a partir de la cual se elaboran reglas de análisis sintáctico; (ii) extracción automática de los candidatos a términos que se correspondían con unigramas y bigramas, y (iii) evaluación de los candidatos extraídos con el asesoramiento de expertos del área médica. Los experimentos fueron realizados en el corpus IULA, conformado por textos médicos en español. Los resultados obtenidos fueron alentadores, ya que se logró un 67% y 68% de precisión en las enumeraciones detectadas para unigramas y bigramas respectivamente.Sociedad Argentina de Informática e Investigación Operativ
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