First electrochemical immunosensor for the rapid detection of mustard seeds in plant food extracts.

This paper describes the first biosensor reported to date for the determination of mustard seed traces. The biosensor consists of an amperometric immunosensing platform able to sensitively and selectively determine Sin a 1 content, the major allergen of yellow mustard and the most abundant protein of these seeds. The immunosensing platform exploits the coupling of magnetic microbeads (MBs) modified with sandwich-type immune complexes, comprising polyclonal and monoclonal antibodies, selective to the target protein for its capturing and detection, respectively. In addition, a HRP-conjugated secondary antibody was used for enzymatic labelling of the monoclonal antibody, and amperometric transduction was made at screen-printed carbon electrodes (SPCEs) using the hydroquinone (HQ)/H2O2 system. The electrochemical immunosensor allows the simple and fast detection (a single 1-h incubation step) of Sin a 1 with a limit of detection of 0.82 ng mL-1 (20.5 pg of protein in 25 µL of sample) with high selectivity against structurally similar non-target allergenic proteins (such as Pin p 1 from pine nut). The developed immunoplatform was successfully used for the analysis of peanut, rapeseed, cashew, pine nut and yellow mustard extracts, giving only positive response for the yellow mustard extract with a Sin a 1 content, in full agreement with that provided by conventional ELISA methodology.

Resección de la primera fila del carpo en pacientes mayores de 50 años: 3 a 16 años de seguimiento / Proximal row carpectomy in patients older than 50 years: 3 to 16 years of follow-up

Objetivo: Conocer los resultados a largo plazo y el pronóstico de los pacientes que han sido intervenidos de resección de la primera fila del carpo (RPFC) en nuestro centro. Material y método: Realizamos un estudio retrospectivo de 14 pacientes intervenidos de RPFC con un seguimiento de 3 a 16 años. Se evaluaron la movilidad, la capacidad funcional mediante el cuestionario Patient-Rated Wrist Evaluation (PRWE) y la capacidad para realizar las actividades de la vida diaria tras la intervención. Resultados: El balance articular fue satisfactorio. La puntuación media en la escala PRWE fue de 20,9+/-17,2 para la subescala de dolor y de 39+/-35,5 para la subescala de funcionalidad. Ningún paciente había precisado reintervención ni han desarrollado complicaciones. El 80% de los pacientes estuvieron satisfechos o muy satisfechos. El 90% de los pacientes volvería a operarse. Discusión: El rango de movimiento de la muñeca es similar con las diferentes técnicas de preservación de la movilidad. Los cambios artrósicos en la articulación radio-hueso grande secundarios a esta intervención no producen necesariamente dolor. Algunos autores han descrito que el grado de satisfacción de la RPFC es comparable con el de otros procedimientos, como la artrodesis en 4 esquinas con placa circular o artrodesis mediocarpiana con agujas. Conclusión: La RPFC tiene alta tasa de satisfacción entre los pacientes con alivio del dolor, buena movilidad y funcionalidad postoperatoria de la muñeca. Además, presenta escasas complicaciones

Objective: To analyze the long-term results and the prognosis of patients who have undergone proximal row carpectomy (PRC) in our hospital. Material and method: This is a retrospective study of 14 patients undergoing PRC with a follow-up of 3 to 16 years. The ability to perform daily activities, mobility and functional capacity after the surgery were assessed using the Patient-Rated Wrist Evaluation questionnaire (PRWE). Results: The range of movement was satisfactory. The mean score on the PRWE scale was 20.9+/-17.2 for the pain subscale and 39+/-35.5 for the functional capacity subscale. None of the patients required revision surgery or developed complications. Eighty percent of the patients were satisfied or very satisfied. Ninety percent of the patients would undergo surgery again. Discussion: The wrist's range of movement achieved with this technique is similar to that obtained with other mobility preservation techniques. Secondary arthritic changes in the radio-capitate joint do not necessarily produce pain. Some authors have described that the degree of satisfaction after PRC is equivalent to that of other procedures such as arthrodesis in 4 corners with circular plate arthrodesis or middle-carpal arthrodesis. Conclusion: PRC achieved high satisfaction rates among the patients providing pain relief, good mobility and post-operative functionality of the wrist. In addition, it presented few complications

Proximal row carpectomy in patients older than 50 years: 3 to 16 years of follow-up. / Resección de la primera fila del carpo en pacientes mayores de 50 años: 3 a 16 años de seguimiento.

OBJECTIVE: To analyze the long-term results and the prognosis of patients who have undergone proximal row carpectomy (PRC) in our hospital. MATERIAL AND METHOD: This is a retrospective study of 14 patients undergoing PRC with a follow-up of 3 to 16 years. The ability to perform daily activities, mobility and functional capacity after the surgery were assessed using the Patient-Rated Wrist Evaluation questionnaire (PRWE). RESULTS: The range of movement was satisfactory. The mean score on the PRWE scale was 20.9±17.2 for the pain subscale and 39±35.5 for the functional capacity subscale. None of the patients required revision surgery or developed complications. Eighty percent of the patients were satisfied or very satisfied. Ninety percent of the patients would undergo surgery again. DISCUSSION: The wrist's range of movement achieved with this technique is similar to that obtained with other mobility preservation techniques. Secondary arthritic changes in the radio-capitate joint do not necessarily produce pain. Some authors have described that the degree of satisfaction after PRC is equivalent to that of other procedures such as arthrodesis in 4 corners with circular plate arthrodesis or middle-carpal arthrodesis. CONCLUSION: PRC achieved high satisfaction rates among the patients providing pain relief, good mobility and post-operative functionality of the wrist. In addition, it presented few complications.

Medial and lateral exostoses of the distal phalanx of the hallux: A potentially painful bunion-like structure. Part 1: Incidence and clinical application.

BACKGROUND: Exostoses at the base of the distal phalanx of the great toe are usually asymptomatic. The literature has not generally considered them as the origin of a possible problem resulting from a pressure conflict between hallux and shoe (medial aspect) or second toe (lateral aspect) nor a potential complication of surgical correction of hallux valgus deformity. No studies, to our knowledge, have evaluated its possible correlation with other foot disorders. When one of these neglected exostoses became painful after surgical correction of hallux valgus, we decided to start a study to determine their possible origin, prevalence in daily practice and histo-pathological morphology. METHODS: Two hundred and fifty-four feet of patients (average age 41.7y.) were enrolled in the study from January 2007 to June 2009. Dorsoplantar weight-bearing radiographs were used to analyze the presence of exostoses and their correlation with the distal phalanx morphology, metatarsal formula (or transverse plane orientation of the metatarsal heads parabola) and hallux valgus angles. Patients were classified according to their age and main symptom for consultation. Four exostoses removed from cadaver feet were also analyzed microscopically. RESULTS: Osseous excrescences arising on the medial or lateral aspect at the proximal part of the terminal phalanx of the hallux were observed in 132 feet (51.9%). Thirty-five feet out of these 132 (13.7%) had exostoses on both sides of the phalanx.A statistically significant positive correlation was found between the presence of a medial exostosis of the phalanx and the severity of HVA. Patients with higher IPH and asymmetry angles have a lower prevalence of medial exostoses (p<0.05). Amongst the different morphologies of the second phalanx, exostoses were most likely found in the standard form. CONCLUSIONS: Prevalence of exostoses at the base of the distal phalanx is high (51.9% of the studied feet). Histological findings would suggest that these exostoses could be considered a mechanical reactive process, produced by a chronic irritation by shoes. We encourage surgeons to be aware of its potential clinical implications. Direct resection is very simple and the most appropriate treatment for symptomatic cases.

Sensitive electrochemical determination of miRNAs based on a sandwich assay onto magnetic microcarriers and hybridization chain reaction amplification.

A novel electrochemical approach for determination of miRNAs involving a sandwich hybridization assay onto streptavidin-magnetic beads (Strep-MBs), hybridization chain reaction (HCR) amplification and amperometric detection at disposable screen-printed carbon electrodes is reported. Using miRNA-21 as the target analyte, a dynamic linear range from 0.2 to 5.0nM with a 60pM (1.5fmol in 25µL) detection limit was obtained. The achieved sensitivity is 24-fold higher than a non-HCR amplification approach involving conventional sandwich type assay onto MBs. Moreover, the whole assay time lasted 1h 45min which is remarkably shorter than other reported methodologies. The methodology exhibited full selectivity against other non-complementary miRNAs as well as an acceptable discrimination between homologous miRNA family members. The applicability of this novel approach was demonstrated by determining mature miRNA-21 in total RNA (RNAt) extracted from tumor cells and human tissues.

Automatic bionalyzer using an integrated amperometric biosensor for the determination of L-malic acid in wines.

A new automatic bioanalyzer for L-malic acid using an integrated amperometric biosensor as detector is reported for the first time in this work. The biosensor is constructed by gold film sputtering deposition on a stainless steel disk electrode and co-immobilization of the enzymes malate dehydrogenase (MDH) and diaphorase (DP) together with the redox mediator tetrathiafulvalene (TTF) by means of dialysis membrane. The analytical performance of the biosensor was evaluated when it was used as amperometric detector in three different analytical methodologies: stirred solutions, semiautomatic FIA system and automatic bioanalyzer. The bienzyme biosensor exhibited great analytical performance in terms of sensitivity, selectivity and reproducibility of the measurements and its usefulness was demonstrated by analyzing wine reference materials with certified content of L-malic acid. The attractive analytical and operational characteristics demonstrated by the automatic bioanalyzer make it a promising simple, rapid and field-based tool for routine wine and fruit control.

Electrochemical bioplatforms for the simultaneous determination of interleukin (IL)-8 mRNA and IL-8 protein oral cancer biomarkers in raw saliva.

The development of electrochemical magnetobiosensors for the simultaneous determination of two biomarkers associated with salivary oral cancer, protein IL-8 and its messenger RNA (IL-8 mRNA) associated, in undiluted human saliva samples is reported in this work. The implemented methodology involves the use of functionalized magnetic beads, specific antibodies against IL-8 protein, a specific hairpin DNA sequence for IL-8 mRNA and amperometric detection at disposable dual screen printed carbon electrodes. This methodology exhibits high sensitivity and selectivity for the target analytes providing detection limits of 0.21 nM for IL-8 mRNA and 72.4 pgmL(-1) (far below the clinical established cut-off of 600 pgmL(-1)) for IL-8 protein in undiluted saliva samples. The dual amperometric magnetobiosensor was applied to the direct determination of both biomarkers in spiked raw saliva samples and to determine the endogenous content of IL-8 protein in saliva samples from 7 healthy individuals. The obtained results were statistically in agreement with those provided by a commercial ELISA kit.

Sensitive and selective magnetoimmunosensing platform for determination of the food allergen Ara h 1.

A highly sensitive disposable amperometric immunosensor based on the use of magnetic beads (MBs) is described for determination of Ara h 1, the major peanut allergen, in only 2h. The approach uses a sandwich configuration involving selective capture and biotinylated detector antibodies and carboxylic acid-modified MBs (HOOC-MBs). The MBs bearing the immunoconjugates are captured by a magnet placed under the surface of a disposable screen-printed carbon electrode (SPCE) and the affinity reactions are monitored amperometrically at -0.20 V (vs a Ag pseudo-reference electrode) in the presence of hydroquinone (HQ) as electron transfer mediator and upon addition of H2O2 as the enzyme substrate. The developed immunosensor exhibits a wide range of linearity between 20.8 and 1000.0 ng mL(-1) Ara h 1, a detection limit of 6.3 ng mL(-1), a great selectivity, a good reproducibility with a RSD of 6.3% for six different immunosensors and a useful lifetime of 25 days. The usefulness of the immunosensor was demonstrated by determining Ara h 1 in different matrices (food extracts and saliva). The results correlated properly with those provided by a commercial ELISA method offering a reliable and promising analytical screening tool in the development of user-friendly devices for on-site determination of Ara h 1.

Electrochemical magnetoimmunosensing platform for determination of the milk allergen ß-lactoglobulin.

A very sensitive magnetoimmunosensor for the determination of ß-lactoglobulin (ß-LG) is reported in this work. A sandwich configuration involving covalent immobilization of the capture antibody (antiß-LG) onto activated carboxylic-modified magnetic beads (HOOC-MBs) and incubation of the modified MBs with a horseradish peroxidase labeled antibody (HRP-antiß-LG), is used. The resulting modified MBs are captured by a magnet placed under the surface of a disposable carbon screen-printed electrode (SPCE) and the amperometric responses are measured at -0.20 V (vs. Ag pseudo-reference electrode), upon addition of hydroquinone (HQ) as electron transfer mediator and H2O2 as the enzyme substrate. The ß-LG magnetoimmunosensor exhibited a wide range of linearity (2.8-100 ng mL(-1)) and a low detection limit of 0.8 ng mL(-1) (20 pg in 25 µL sample). The magnetoimmunosensing platform was successfully applied for the detection of ß-LG in different types of milk without any matrix effect after just a sample dilution. The results correlated properly with those provided by a commercial ELISA method offering a truthful analytical screening tool. These features make the developed methodology a promising alternative in the development of user-friendly devices for on-site determination of ß-LG in dairy products.

Simultaneous detection of two breast cancer-related miRNAs in tumor tissues using p19-based disposable amperometric magnetobiosensing platforms.

A novel magnetobiosensing approach for the rapid and simultaneous detection of two breast cancer-related miRs (miR-21 and miR-205) is reported. It involves the use of antimiR-21 and antimiR-205 specific probes, chitin-modified magnetic beads (Chitin-MBs), the p19 viral protein as capture bioreceptor and amperometric detection with the H2O2/hydroquinone (HQ) system at dual screen-printed carbon electrodes (SPdCEs). The use of SPdCEs allows the simultaneous independent amperometric readout for each target miR to be measured. The magnetosensor exhibited sensitive and selective detection with dynamic ranges from 2.0 to 10.0nM and detection limits of 0.6nM (6fmol) for both target miRs without any amplification step in less than 2h. The usefulness of the approach was evaluated by detecting the endogenous levels of both target miRs in total RNA (RNAt) extracted from metastatic breast cancer cell lines and human tissues.

Rapid screening of multiple antibiotic residues in milk using disposable amperometric magnetosensors.

Disposable amperometric magnetosensors, involving a mixture of modified-magnetic beads (MBs), for the multiplex screening of cephalosporins (CPHs), sulfonamides (SAs) and tetracyclines (TCs) antibiotic residues in milk are reported for the first time in this work. The multiplexed detection relies on the use of a mixture of target specific modified magnetic beads (MBs) and application of direct competitive assays using horseradish peroxidase (HRP)-labeled tracers. The amperometric responses measured at -0.20 V vs. the Ag pseudo-reference electrode of screen-printed carbon electrodes (SPCE) upon the addition of H2O2 in the presence of hydroquinone (HQ) as redox mediator, were used to monitor the extent of the different affinity reactions. The developed methodology, involving a simple and short pretreatment, allowed discrimination between no contaminated UHT and raw milk samples and samples containing antibiotic residues at the maximum residue limits (MRLs). The usefulness of the multiplexed magnetosensor was demonstrated by analyzing spiked milk samples in only 5 min. The results demonstrated that a clear discrimination of milk samples contaminated with antibiotics at their MRL level or their mixtures, allowing the identification of milk not complying with current legislation. These features make the developed methodology a promising alternative in the development of user-friendly devices for on-site analysis to ensure quality control for dairy products.

Genetic deletion of aquaporin-1 results in microcardia and low blood pressure in mouse with intact nitric oxide-dependent relaxation, but enhanced prostanoids-dependent relaxation.

The water channels, aquaporins (AQPs) are key mediators of transcellular fluid transport. However, their expression and role in cardiac tissue is poorly characterized. Particularly, AQP1 was suggested to transport other molecules (nitric oxide (NO), hydrogen peroxide (H2O2)) with potential major bearing on cardiovascular physiology. We therefore examined the expression of all AQPs and the phenotype of AQP1 knockout mice (vs. wild-type littermates) under implanted telemetry in vivo, as well as endothelium-dependent relaxation in isolated aortas and resistance vessels ex vivo. Four aquaporins were expressed in wild-type heart tissue (AQP1, AQP7, AQP4, AQP8) and two aquaporins in aortic and mesenteric vessels (AQP1-AQP7). AQP1 was expressed in endothelial as well as cardiac and vascular muscle cells and co-segregated with caveolin-1. AQP1 knockout (KO) mice exhibited a prominent microcardia and decreased myocyte transverse dimensions despite no change in capillary density. Both male and female AQP1 KO mice had lower mean BP, which was not attributable to altered water balance or autonomic dysfunction (from baroreflex and frequency analysis of BP and HR variability). NO-dependent BP variability was unperturbed. Accordingly, endothelium-derived hyperpolarizing factor (EDH(F)) or NO-dependent relaxation were unchanged in aorta or resistance vessels ex vivo. However, AQP1 KO mesenteric vessels exhibited an increase in endothelial prostanoids-dependent relaxation, together with increased expression of COX-2. This enhanced relaxation was abrogated by COX inhibition. We conclude that AQP1 does not regulate the endothelial EDH or NO-dependent relaxation ex vivo or in vivo, but its deletion decreases baseline BP together with increased prostanoids-dependent relaxation in resistance vessels. Strikingly, this was associated with microcardia, unrelated to perturbed angiogenesis. This may raise interest for new inhibitors of AQP1 and their use to treat hypertrophic cardiac remodeling.

About an unusual systemic disorder: report of a cryptic miliary tuberculosis.

We report here the case of a young Chinese woman with cryptic miliary tuberculosis associated with acute hepatitis, pancytopenia, biological disseminated intravascular coagulation (DIC), and hyponatremia. Following the introduction of a classic tuberculostatic treatment, her general status quickly improved. After an extensive review of the literature, this is, to the best of our knowledge, the first case of cryptogenic miliary tuberculosis with all its cumulative complications.

Influence of chloride ion on electrochemical degradation of phenol in alkaline medium using bismuth doped and pure PbO2 anodes.

Electrochemical method at laboratory scale for the treatment of biorefractory solutions with high phenol content--1000 ppm is described. Total degradation of phenol was obtained at alkaline pH when NaCl was present using Bi-doped and pure lead dioxide electrodes. A filter press cell of 63 cm2 geometric area was used for this purpose. Measurements of chemical oxygen demand (COD), phenol, carbon monoxide, carbon dioxide, and volatile organic compounds (VOCs) have been used to characterise the electrochemical process for phenol elimination. It is worth noting that in the absence of NaCl, the charge efficiency of COD removal was independent of the current density in the range studied (50-100 mA cm(-2)) Moreover, when NaCl was present, the current efficiency for COD and phenol removal increase as the chloride concentration increases. Chloroform was the only halocompound detected at the end of reaction. For both electrodes, Bi-doped and pure lead dioxide, the chloroform concentration at the end of the electrolysis decreases, working at low current densities and for low chloride concentrations.