Multienzymatic system immobilization in sol-gel slides: fluorescent superoxide biosensors development.

One of the potential areas of research in the development of biosensors is the production of analytical devices based on the use of immobilized multienzymatic systems. In this work, we report the development of three analytical systems for superoxide radical detection using sol-gel technology to immobilize enzyme systems. These systems are based on the connected reactions of three enzymes (xanthine oxidase, superoxide dismutase and horseradish peroxidase) coupled to the probe Amplex red. The difference between these three systems lies in the immobilization of two or three enzymes into a single or in different sol-gel slides. We check the potential use of each designed systems to quantify superoxide radical and potential evaluation of radical scavenging properties of several antioxidant compounds.

Development of a dual-analyte fluorescent sensor for the determination of bioactive nitrite and selenite in water samples.

Nitrite and selenium are two bioactive compounds found in the environment which show beneficial effects for health at low levels but have toxic effects at higher doses. Consequently, quantification of both analytes in water samples results of great interest in areas such as biomedicine, food technology and environmental analysis. In a recent paper, we immobilized the inclusion complex formed between 2,3-diaminonaphthalene (DAN) and 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD) in a sol-gel matrix, in order to prepare a highly sensitive reagentless fluorescence-based sensor for the specific measurement of nitrite. Here we have explored the possibility of using the sol-gel immobilized complex to quantify selenite (Se (IV)), the more toxic form of selenium, as well as to act as a dual-analyte chemical sensor for simultaneous quantification of both nitrite and selenite in aqueous samples. Results show that (a) inclusion of DAN in HP-beta-CD and its subsequent immobilization in a sol-gel matrix do not modify the reactivity of DAN against selenite, (b) the reaction product formed (4,5-benzopiazselenol) remains into the cyclodextrin increasing considerably its fluorescence quantum yield and avoiding, therefore, its extraction into organic solvents, (c) the developed sensor can detect selenite concentrations at submicromolar level with a minimum detection limit of 13 nM, (d) the immobilized system is able to simultaneously quantify nitrite and selenite at submicromolar concentrations in natural water samples with no further sample pre-treatment.

Immobilization and characterization of 2,3-diaminonaphthalene/cyclodextrin complexes in a sol-gel matrix: a new fluorimetric sensor for nitrite.

The aromatic diamino compound 2,3-diaminonaphthalene (DAN) has been extensively used to detect and quantify nitrite ions in biological and environmental samples. We have immobilized the DAN reagent in a porous silicate glass matrix, via previous incorporation of the dye in HP-beta-CD. Changes in fluorescence intensity were used to characterize the inclusion complexes and determine the association constant and stoichiometry of the process. Fluorescence spectrum of these complexes was also used to monitor their immobilization within the sol-gel matrix. Reactivity of the immobilized complexes was evaluated with increasing concentrations of nitrite up to 10 microM (with a detection limit around 20 nM). Results show that sol-gel immobilization does not modify the reactivity of the dye against nitrite and serves to prepare a highly sensitive ready to use fluorescence-based sensor for the specific measurement of nitrite at submicromolar concentrations with no further sample pretreatment.

[Headache, does it cause a health care overload in primary health care? Urban area vs rural area medical visit]. / Cefalea, ¿una sobrecarga asistencial en atención primaria? Consulta urbana frente a consulta rural.

OBJECTIVES: Headache causes an overload and a problem to out-patient neurology. There are few studies that quantify the overload that the headache causes in a primary health care out-patient clinic visit. The aim of the present study is to identify and quantify the real load that this disease supposes in two primary health care consultations, one located in a rural area and another in an urban area. MATERIAL AND METHODS: A 6 month long observational and descritive study. The total number of patients seen, the number of patients seen for headache and their diagnostic classification were recorded. RESULTS: A total of 6,014 visits were counted. Only 46 patients consulted due to headache (0,76%). Tensional headache was the most frequently diagnosed headache (43.48%) followed by migraine (23.91%). CONCLUSIONS: Our study verifies that published by other authors and determines that, on the contrary to that which occurs in the neurology out-patient clinic, headache does not cause a daily work overload for the general practitioner. The scarce number of consultations for headache, with the diagnosis and management involved in this disease, makes it necessary to consider a multidisciplinary health care problem such as headache differently according to the health care level involved.

Cefalea, ¿una sobrecarga asistencial en atención primaria? Consulta urbana frente a consulta rural / Headache, does it cause a health care overload in Primary Health Care? Urban area vs rural area medical visit

El dolor de cabeza supone una sobrecargay unun problema asistencial en cualquier consulta ambulatoriade neurología. Existen pocos estudios que cuantifiquen lasobrecarga que supone el dolor de cabeza en una consultade atención primaria. El objetivo del presente estudio esidentificar y cuantificar realmente la carga que esta patologíasupone en dos consultas de atención primaria, una localizadaen un ámbito rural y otra en un ámbito urbano.Material y métodos. Estudio observacional y descriptivode 6 meses de duración. Se registra el total de pacientesatendidos, el número de pacientes asistidos por dolor de cabezay su clasificación diagnóstica.Resultados. Se contabilizó un total de 6.014 consultas.Sólo 46 pacientes consultan por cefalea (0,76%). La cefaleatensional es el dolor de cabeza diagnosticado con más frecuencia(el 43,48%), seguido de la migraña (el 23,91%).Conclusiones. Nuestro estudio certifica lo publicadopor otros autores y determina que, contrariamente a lo quesucede en la neurología ambulatoria, la cefalea no suponeuna carga en el trabajo diario de un médico de familia. Elescaso número de consultas por cefalea, con los problemasde diagnóstico y manejo que rodea a esta patología, originanque un problema de atención multidisciplinar como lacefalea se afronte de diferente manera según el nivel asistencialdonde uno se encuentre (AU)

Objectives. Headache causes an overload and a problemto out-patient neurology. There are few studies that quantify the overload that the headache causes in a PrimaryHealth Care out-patient clinic visit. The aim of thepresent study is to identify and quantify the real loadthat this disease supposes in two Primary Health Careconsultations, one located in a rural area and another inan urban area.Material and methods. A 6 month long observationaland descritive study. The total number of patients seen,the number of patients seen for headache and theirdiagnostic classification were recorded.Results. A total of 6,014 visits were counted. Only46 patients consulted due to headache (0,76%). Tensionalheadache was the most frequently diagnosed headache(43.48%) followed by migraine (23.91%).Conclusions. Our study verifies that published byother authors and determines that, on the contrary tothat which occcurs in the neurology out-patient clinic,headache does not cause a daily work overload for thegeneral practitioner. The scarce number of consultationsfor headache, with the diagnosis and management involvedin this disease, makes it necessary to consider a multidisciplinaryhealth care problem such as headache differentlyaccording to the health care level involved (AU)