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La incidencia de la sepsis continúa aumentando. Se define como la disfunción orgánica potencialmente mortal, secundaria a la respuesta anómala ante una infección.

Las alteraciones del metabolismo del potasio son muy frecuentes en la práctica clínica, con un espectro de presentación que varía desde leve hipopotasemia asintomática secundaria al uso de diuréticos a hiperpotasemia grave con riesgo de arritmias graves o parada cardiaca. Tanto la hipopotasemia como la hiperpotasemia ocasionan una alteración de la polarización de la membrana celular, dando lugar a una alteración en la excitabilidad del corazón, tejido nervioso y del musculo liso y esquelético. Por tanto, es esencial tanto el conocimiento de la homeostasis para poder evitar sus efectos deletéreos, como el reconocimiento precoz de este trastorno electrolítico para poder instaurar rápidamente un tratamiento eficaz.

La acidosis metabólica es un trastorno ácido base que tiende a producir acidemia (descenso en el pH) por cambios primarios en la concentración de bicarbonato. Se clasifica en normoclorémica o hiperclorémica según el valor del anión gap (AG) del plasma; parámetro que representa la diferencia entre las principales cargas positivas (cationes) y negativas (aniones). La causa de la acidosis metabólica debe valorarse según la anamnesis y el contexto clínico del paciente, pero toda valoración de acidosis debe incluir gasometría, determinación de electrolitos, medición de la respuesta compensatoria respiratoria, del AG y del cociente ΔAG/ΔHCO.

Las alteraciones del equilibrio ácido base pueden suceder con carácter primario pero, en general, derivan de la complicación de una enfermedad preexistente. Por ello, no es raro que una caracterización correcta del equilibrio ácido base sea la pista fundamental para identificar un proceso causal insospechado hasta entonces. La frecuencia de estas anomalías es elevada, especialmente en pacientes hospitalizados, y su aparición tiene claras implicaciones pronósticas.

HAART has increased the life expectancy of patients with HIV. However, as their life expectancy increases, it becomes increasingly important to focus on the management of concurrent illnesses such as chronic HBV and HCV infections which have the potential to increase mid to long term morbidity and mortality. Shared epidemiological risks have resulted in the HIV infected population having a higher incidence of both HBV and HCV than those uninfected with HIV. Co-infection with HIV modifies the natural history of HBV infection, increasing the rate of viral replication, risk of carriage and chronic hepatitis but without increasing liver necroinflammatory processes. In chronic HCV infection, the presence of HIV enhances the risk of severe liver disease. There is no evidence as yet that HBV directly impacts on HIV disease progression but HCV infection increases the risk of death or an AIDS defining illness and impairs CD4+ T cell recovery during antiretroviral therapy. Treatment of either hepatitis virus is complex because of pharmacokinetic interactions with components of HAART regimens. Copyright © 2001 John Wiley & Sons, Ltd.

Tungstates and molybdates of Ca, Sr and Cd have been prepared by precipitation. X-ray diffractograms prove them to be stoichiometric compounds with scheelite structure. The surface of the products and its evolution with thermal treatment have been studied by thermogravimetry and scanning electron microscopy. Finally, BET specific surface areas have been determined as well as pore volume distribution by adsorption-desorption of nitrogen and mercury porosimetry.

Water pollution by pesticides used in agriculture is currently a major concern both in Spain and in Europe as a whole, prompting the need to evaluate water quality and ecological risk in areas of intensive agriculture. This study involved monitoring pesticide residues and certain degradation products in surface and ground waters of the Denomination of Origin (DO) Jumilla vineyard area in Spain. Sixty‐nine pesticides were selected and evaluated at twenty‐one sampling points using a multi‐residue analytical method, based on solid‐phase extraction (SPE) and analysis by liquid chromatography coupled with mass spectrometry (LC‐MS), providing reliable results. Twenty‐six compounds from those selected were detected in the samples analyzed (eleven insecticides including one degradation product, nine herbicides, and six fungicides) and fifteen of them were found in concentrations over 0.1 μg L−1 (upper threshold established by the EU for pesticides detected in waters for human consumption). Indoxacarb was present in more than 70% of the samples, being the most frequently detected compound in water samples. Some pesticides were ubiquitous in all the water samples. Ecotoxicological risk indicators, toxic units (TUs) and risk quotients (RQs), for algae, Daphnia magna and fish were calculated to estimate the environmental risk of the presence of pesticides in waters. The compounds with the highest risk were the herbicides pendimethalin, with RQ values > 1 for the three aquatic organisms, and diflufenican, posing a high risk for algae and fish, and the insecticide chlorpyrifos, with a high risk for Daphnia magna and fish. The ΣTUi determined for water at each sampling point posed only a high risk for the three aquatic organisms in a sample. These results are important for considering the selection of pesticides with less environmental risk in intensive agricultural areas. [ABSTRACT FROM AUTHOR]