Multi-tasking Schiff base ligand: a new concept of AuNPs synthesis.

Multi-tasking 3,4-dihydroxysalophen Schiff base tetradentate ligand (3,4-DHS) as reductant, stabilizer, and catalyst in a new concept of gold nanoparticles (AuNPs) synthesis is demonstrated. 3,4-DHS is able to reduce HAuCl4 in water, acting also as capping agent for the generation of stable colloidal suspensions of Schiff base ligand-AuNPs assemblies of controlled size by providing a robust coating to AuNPs, within a unique reaction step. Once deposited on carbon electrodes, 3,4-DHS-AuNPs assemblies show a potent electrocatalytic effect towards hydrazine oxidation and hydrogen peroxide oxidation/reduction.

Immunosensing platform based on gallium nanoparticle arrays on silicon substrates.

Gallium nanoparticles (GaNPs) of different sizes are deposited on Si(100) substrates by thermal evaporation. Through ellipsometric analysis, it is possible to investigate the plasmonic effects in the GaNPs and exploit them to develop biosensors. The excitation of the resonant modes for certain incidence angles leads to negative values of the imaginary part of the pseudodielectric function (<εi>) obtained in ellipsometry. Furthermore, there is an abrupt sign change when the difference between the phase shifts of p- and s-polarization components reaches 180° at an energy of around 3.15 eV. At that energy, reversal of the polarization handedness (RPH) occurs for an elliptically-polarized input beam. The energy of the RPH condition reduces as the evaporation time increases. The slope of <εi> at the RPH condition is extremely sensitive to changes in the surrounding medium of the NP surface and prompts the use of the GaNP/Si system as sensor platform. Fourier transformed infrared spectroscopy (FTIR) is used before and after functionalization with 3,3'-dithiodipropionic acid di(N-succinimidyl ester) and a glutathione-specific antibody to confirm the chemical modification of the sample surface. The developed immunosensor is exposed to different concentrations of glutathione (GSH) showing a linear relationship between the slope of the pseudodielectric function at the RPH condition and the GSH concentration. The immunosensor shows a limit of detection of 10nM enabling its use for the detection of low GSH levels in different medical conditions.

[Comorbidity as a predictor of health services utilization and mortality in patients with diabetes]. / Comorbilidad como predictor de utilización de servicios sanitarios y mortalidad en pacientes con diabetes.

OBJECTIVE: Chronic diseases are the main cause of mortality worldwide. Study of the most prevalent diseases is essential, as well as the development of indicators of health services' utilization and mortality in these patients. The objective of this study was to identify which comorbidity measure best predicts health services' utilization and mortality in patients with diabetes mellitus in our environment. METHODS: A longitudinal study was carried out in a cohort of diabetes mellitus patients diagnosed in 2006 in Zaragoza and followed up to 2010. Logistic regression predictive models were developed. The number of diagnosis, the number of ambulatory diagnostic groups (ADG), and the number of major ambulatory diagnostic groups (MADG) from the Ambulatory Care Groups system were used as comorbidity measures. The validity measure consisted of the improvement in the model's explanatory capacity (c-statistic). RESULTS: The prevalence of diabetes mellitus was 8.8%. Both the number of diagnoses and comorbidity were associated with health services' utilization and mortality. For mortality, the best indicator of comorbidity was the number of MADGs (c=0.763). The model adjusted by sex, age, number of MADGs, and number of hospitalizations had the highest explanatory capacity (c=0.818). CONCLUSIONS: The ACG system allows resource consumption and mortality to be predicted in people with diabetes mellitus in our environment. This study confirms the substantial healthcare burden generated by patients with diabetes mellitus and the need to tackle this situation.

The quality of outpatient antimicrobial prescribing: a comparison between two areas of northern and southern Europe.

PURPOSE: The aim of the study was to analyse and compare the quality of outpatient antimicrobial prescribing in Denmark and Aragón (in northeastern Spain), with the objective of assessing inappropriate prescribing. METHODS: Outpatient antimicrobial prescription data were obtained from the National Institute for Health Data and Disease Control in Denmark, and from the Aragón Information System of Drug Consumption. The number of Defined Daily Doses (DDD) of the different substances were calculated, and the quality of the antimicrobial prescription was analysed using the 'Drug Utilization 90 %' method and the European Surveillance of Antimicrobial Consumption (ESAC) quality indicators for outpatient antimicrobial use. RESULTS: The majority of the prescriptions (90 % of total DDD) were comprised of 14 (of 39) different antimicrobials in Denmark, based mainly on narrow spectrum penicillin, and 11 (of 59) antimicrobials in Aragón, principally broad spectrum penicillins. The quality indicators described an elevated consumption of antimicrobials and an important seasonal variation in Aragón. In Denmark, the values obtained reflected a more moderate use with minor seasonal variation. CONCLUSIONS: The results showed important differences between the two study areas in relation to quantity and quality of outpatient antimicrobial prescription. The data indicate an overuse (and/or misuse) of antimicrobials in the Spanish region, despite national and local guidelines. The pattern of prescription in Denmark reflects a better adherence to recommendations.

[Public hospital utilization by the foreign population in Aragon, Spain (2004-2007)]. / Utilización de los hospitales públicos por la población extranjera en Aragón (2004-2007).

OBJECTIVES: To describe hospitalization rates and hospital morbidity among the foreign population residing in Aragon (Spain) by country of birth, between 2004 and 2007, and to compare these rates with those in the autochthonous population. METHODS: A retrospective longitudinal study was carried out of hospital discharges of the foreign population in public hospitals in Aragon. Utilization rates were estimated by sex, age, country of birth and main diagnosis. Poisson regression was used to estimate the utilization rate ratios and their 95% confidence intervals. RESULTS: Hospitalization rates were lower in the foreign population (adjusted RR: 0.52; 95% CI: 0.51-0.56), except in women aged between 15 and 24 years (RR: 2.9; 95% CI: 2.8-3.0) and among those born in the Maghreb (RR: 1.8; 95% CI: 1.7; 1.9), sub-Saharan Africa (RR: 2.0; 95% CI: 1.9-2.1) and Asia (RR=1.4; 95% CI: 1.3-1.6). When hospital discharges related to obstetrics and gynecology were excluded, only women born in sub-Saharan Africa continued to have adjusted RR greater than 1. These women had higher hospitalization rates in groups of infectious and parasitic diseases (RR: 2.5) and blood and blood-forming organs (RR: 2.8). CONCLUSIONS: In Aragon (Spain), public hospital utilization is lower in foreigners than in the autochthonous population. The diseases treated varied by country of birth. The diseases prevalent in these countries, together with hereditary diseases, can increase hospital utilization rates.

Interactions of Schiff-base ligands with gold nanoparticles: structural, optical and electrocatalytic studies.

A study on optical and electrochemical properties resulting upon interaction of Schiff base ligands with gold nanoparticles is presented. The measurements of the optical absorption and fluorescence properties have provided important information about structure-properties dependence. We show that in function of the isomer structure and its attachment orientation with respect to the metal nanoparticle, their optical properties can be modulated. Nanoparticle assemblies mediated by 3,4-DHS were also obtained based on a control of the interparticle interactions and their electrocatalytic activity toward NADH oxidation was investigated.

[Is it pertinent to investigate the relations between physicians and the drug industry]. / Es pertinente investigar las relaciones entre médicos e industria farmacéutica?

OBJECTIVE: To analyse the opinions of physicians on the appropriateness of research into the relationships between doctors and pharmaceutical industry, and to evaluate the usefulness of email survey in this research. MATERIAL AND METHODS: Survey via email of 373 authors of papers published in Spanish medical journals in 2007. The relationships between doctors and the industry was measured by asking doctors what they had received from industry during last year, the value in euro, and the number of visits from industry representatives. RESULTS: The response rate was 28.2%. Most physicians (90.5%) considered the study appropriate. Only 3.2% of doctors refused to take part in the study due to disagreeing with methodology. A total of 92.8% received something from industry during last year (62% cost associated with professional meetings, 60% material for continuing medical education). Mean value of gifts received was 900 euro (60-12,000 euro). By sex, women apparently received more drug samples, and men more payments for consulting or enrolling patients in trials. Doctors practicing in hospitals seemed to receive more gifts than primary care doctors, particularly trips or lunch. Number of visits of industry representatives (from 5 to 10 weekly) was associated with more gifts to doctors. CONCLUSIONS: The vast majority of doctors agree with the appropriateness of researching into the relationships between doctors and the pharmaceutical industry. Relationships between physicians and industry appear to be intensive, as seen in other studies. Response rate was low, but the simplicity and speed of the method are valuable advantages.

Synthesis of cobalt ferrite core/metallic shell nanoparticles for the development of a specific PNA/DNA biosensor.

Controlled synthesis of cobalt ferrite superparamagnetic nanoparticles covered with a gold shell has been achieved by an affinity and trap strategy. Magnetic nanoparticles are functionalized with a mixture of amino and thiol groups that facilitate the electrostatic attraction and further chemisorption of gold nanoparticles, respectively. Using these nanoparticles as seeds, a complete coating shell is achieved by gold salt-iterative reduction leading to monodisperse water-soluble gold-covered magnetic nanoparticles, with an average diameter ranging from 21 to 29 nm. These constitute a versatile platform for immobilization of biomolecules via thiol chemistry, which is exemplified by the immobilization of peptide nucleic acid (PNA) oligomers that specifically hybridize with complementary DNA molecules in solution. Hybridation with DNA probes has been measured using Rhodamine 6G fluorescence marker and the detection of a single nucleotide mutation has been achieved. These results suggest the PNA-nanoparticles application as a biosensor for DNA genotyping avoiding commonly time-consuming procedures employed.

[Dependency levels and health care services' utilization in psychiatric hospitals in Aragon (Spain)]. / Niveles de dependencia y utilización de servicios en los hospitales psiquiátricos de Aragón.

OBJECTIVES: To determine the characteristics of patients living in psychiatric hospitals in Aragon, to assess their dependency levels, and to analyze health care services' utilization by these patients. METHODS: We performed a cross-sectional study between July 1 and November 31. The questionnaire used was the Resident Assessment Instrument- Mental Health (RAI-MH). The sample consisted of 437 patients living in public psychiatric hospitals in Aragon. These hospitals provide care to chronically mentally ill patients and to patients undergoing rehabilitation. The Resource Utilization Group (RUG-I) system was used to classify patients by their dependency levels for activities of daily life (ADL). RESULTS: Of the 437 patients, 259 (59.3%) were men with a mean age of 62.2 years. A total of 82.1% of the patients were classified as RUG-I group 1. Patients in groups 1 and 2 required more formal health care services. At least one visit by a psychiatrist was required by 25.3% of patients in group 1 and by 15.2% of those in group 2 compared with no visits by the other groups. Nursing interventions were more frequently required by patients in the more dependent groups. All of the of patients in groups 2 to 8 needed daily physical assistance for ADL vs. 26.3% of those in group 1. In the multivariate analysis, predictive variables were the hospital and type of unit. CONCLUSIONS: There is wide variation in health care services' utilization by patients living in psychiatric hospitals, which is related to dependency levels. Many psychiatric patients do not need formal psychiatric care. Health care professionals should assess the real needs of patients to provide each of them with appropriate care.