From secondary school to university: associations between sport participation and total and domain-specific sedentary behaviours in Spanish students.

Effective ways to reduce sedentary behaviour in adolescents are needed to mitigate the risk of chronic disease and poor mental health. Organised sport participation is the most practiced physical activity during adolescence. However, the influence sport participation has on sedentary behaviours remains unclear. This study investigated the associations between sport participation, total and domain-specific sedentary behaviour and physical activity during the transition from secondary school to university. A 3-year longitudinal survey followed Spanish secondary school students (n = 113) to their first year of university. Generalized linear models, adjusted by gender and year, assessed the relationships between sport participation, total and domain-specific sedentary behaviour and physical activity. Compared with non-sport participants, teenagers who played individual sports from baseline during secondary school spent significantly less total time sitting (- 110.5 min/day at weekends), watching television (- 18.7 min/day at weekends) or using the computer for leisure (- 37.4 min/day weekdays). Those who played team sports from baseline at secondary school spent less time sitting (- 126.4 min/day at weekends) or socialising (- 37 min/day at weekends)Conclusion: From secondary school to university, sport participation-based interventions might be an effective strategy to reduce sitting time spent on some domain-specific behaviours. Promoting sports could reduce the rise of sedentary behaviour during adolescence, a stage where sedentary behaviour evolves. What is Known: • Sitting too much and for too long is an important risk factor during adolescence. • Replacing adolescent's sedentary time with moderate-to-vigorous physical activity has been associated with a better quality of life. What is New: • Playing sport is associated with spending less time in total SB on the transition from high school to college. • Not all SB domains are linked to sport participation with associations differing from whether participants played individual or team sports.

Applicability of the SPAN-100 index in a prospective and contemporary cohort of patients treated with intravenous rtPA in Catalonia. / Aplicabilidad del índice SPAN-100 en una cohorte prospectiva y contemporánea de pacientes tratados con rtPA por vía intravenosa en Cataluña.

BACKGROUND: Prognostic scales can be helpful for selecting patients for reperfusion treatment. This study aims to assess the prognostic ability of the recently published SPAN-100 index in a large cohort of stroke patients treated with intravenous thrombolysis (IV rtPA). METHODS: Using data from the prospective registery of all reperfusion treatments administered in Catalonia, we selected patients treated with IV rtPA alone between 2011 and 2012. The SPAN-100 index was calculated as the sum of age (years) and NIHSS score, and patients in the cohort were classified as SPAN-100 positive [≥ 100] or SPAN-100 negative [< 100]. We measured raw and adjusted rates of symptomatic intracerebral haemorrhage (SICH), mortality, and 3-month functional outcome (mRS 0-2) for each SPAN-100 category. Area under the ROC curve was calculated to predict the main outcome measures. RESULTS: We studied 1685 rtPA-treated patients, of whom 1405 (83%) were SPAN-100 negative. The SICH rates adjusted for sex, pre-stroke mRS, hypertension, diabetes, dyslipidaemia, ischaemic heart disease, heart failure, atrial fibrillation, prior TIA/stroke and time to thrombolysis did not differ between groups, but likelihood of functional independence (mRS 0-2) at 3 months was nearly 8 times higher in the SPAN-100 negative group than in the positive group. Furthermore, the 3-month mortality rate was 5 times higher in the SPAN-100 positive group. ROC curve analysis showed high specificities for predicting both functional independence and 3-month mortality for a cut-off point of 100. CONCLUSION: The SPAN-100 index is a simple and straightforward method that may be useful for selecting candidates for rtPA treatment in doubtful cases, and for informing patients and their relatives about likely outcomes.

pigk Mutation underlies macho behavior and affects Rohon-Beard cell excitability.

The study of touch-evoked behavior allows investigation of both the cells and circuits that generate a response to tactile stimulation. We investigate a touch-insensitive zebrafish mutant, macho (maco), previously shown to have reduced sodium current amplitude and lack of action potential firing in sensory neurons. In the genomes of mutant but not wild-type embryos, we identify a mutation in the pigk gene. The encoded protein, PigK, functions in attachment of glycophosphatidylinositol anchors to precursor proteins. In wild-type embryos, pigk mRNA is present at times when mutant embryos display behavioral phenotypes. Consistent with the predicted loss of function induced by the mutation, knock-down of PigK phenocopies maco touch insensitivity and leads to reduced sodium current (INa) amplitudes in sensory neurons. We further test whether the genetic defect in pigk underlies the maco phenotype by overexpressing wild-type pigk in mutant embryos. We find that ubiquitous expression of wild-type pigk rescues the touch response in maco mutants. In addition, for maco mutants, expression of wild-type pigk restricted to sensory neurons rescues sodium current amplitudes and action potential firing in sensory neurons. However, expression of wild-type pigk limited to sensory cells of mutant embryos does not allow rescue of the behavioral touch response. Our results demonstrate an essential role for pigk in generation of the touch response beyond that required for maintenance of proper INa density and action potential firing in sensory neurons.

Listeria monocytogenes meningoencephalitis in adults: analysis of factors related to unfavourable outcome.

PURPOSE: To analyse the short-term outcome in patients with Listeria monocytogenes meningoencephalitis (LMME) to improve management and outcome. METHODS: Observational study with adult patients with LMME between 1977 and 2009 at a tertiary hospital in Barcelona, Spain. Parameters that predicted outcome were assessed with univariate and logistic regression analysis. RESULTS: Of 59 cases of LMME, 28 occurred in the last decade. Since 1987, a new protocol has been used and 29/45 patients (64%) treated since then received adjuvant dexamethasone. In patients who received this treatment there was a trend towards fewer neurological sequelae (5 vs 33%; p = 0.052). Antiseizure prophylaxis with phenytoin was administered in 13/45 (28%) patients. Seizures occurred in 7/45 (16%) patients, all in the group who did not receive phenytoin. Hydrocephalus presented in 8/59 (14%). It was never present at admission and five patients needed neurosurgical procedures. Sequelae after 3 months were present in 8/45 (18%), mostly cranial nerve palsy. Rhombencephalitis (RE) was related to the presence of neurologic sequelae (OR: 20.4, 95% CI: 1.76-236). Overall mortality was 14/59 (24%), 9/59 (15%) due to neurological causes related to hydrocephalus or seizures. Mortality was defined as early in 36% and late in 64%. In the multivariate analysis, independent risk factors for mortality were presence of hydrocephalus (OR: 17.8, 95% CI: 2.753-114) and inappropriate empirical antibiotic therapy (OR: 6.5, 95% CI: 1.201-35). CONCLUSIONS: Outcome of LMME may be improved by appropriate empirical antibiotic therapy, suspicion and careful management of hydrocephalus. Use of adjuvant dexamethasone or phenytoin in a subgroup of these patients might have a benefit.

Illustrating the processability of magnetic layered double hydroxides: layer-by-layer assembly of magnetic ultrathin films.

We report the preparation of single-layer layered double hydroxide (LDH) two-dimensional (2D) nanosheets by exfoliation of highly crystalline NiAl-NO3 LDH. Next, these unilamellar moieties have been incorporated layer-by-layer (LbL) into a poly(sodium 4-styrenesulfonate)/LDH nanosheet multilayer ultrathin film (UTF). Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible light (UV-vis), and X-ray diffraction (XRD) profiles have been used to follow the uniform growth of the UTF. The use of a magnetic LDH as the cationic component of the multilayered architecture enables study of the resulting magnetic properties of the UTFs. Our magnetic data show the appearance of spontaneous magnetization at ∼5 K, thus confirming the effective transfer of the magnetic properties of the bulk LDH to the self-assembled film that displays glassy-like ferromagnetic behavior. The high number of bilayers accessible-more than 80-opens the door for the preparation of more-complex hybrid multifunctional materials that combine magnetism with the physical properties provided by other exfoliable layered inorganic hosts.

Arthritis related to systemic meningococcal disease: 34 years' experience.

The purpose of this investigation was to assess the clinical characteristics, therapeutic aspects, and outcome of arthritis related to invasive meningococcal disease (IMD). All episodes of bacterial meningitis and IMD are recorded systematically. We selected all episodes of IMD, with or without meningitis, that presented arthritis. From 1977 to 2010, 522 episodes of IMD were treated. Thirty-nine of these (7.5 %, 26 women, mean age 33 years) presented arthritis. Of these 39, 37 (95 %) presented skin lesions and 31 (79 %) had meningitis. Twenty (51 %) had positive blood cultures and six (15 %) had shock. No differences were found in skin lesions, shock, or bacteremia compared to cases without arthritis. In contrast to other septic forms, arthritis related to IMD was cured with short antibiotic therapy and without surgical drainage. There was no mortality. All patients recovered and none presented joint sequelae; however, 13 adult patients (33 %) required long-term treatment with steroids due to persistent symptoms. Arthritis related to IMD most frequently affects the knees and ankles, and may be a cause of fever relapse. Short antibiotic therapy is enough in all cases and surgical drainage is not needed. In some adult patients, especially those over 50 years of age, evolution is torpid and steroid therapy may be required in order to achieve recovery.

[Chronic rheumatic manifestations following chikungunya virus infection: clinical description and therapeutic considerations]. / Manifestations chroniques rhumatologiques post-infection a virus chikungunya: description clinique et orientations thérapeutiques.

The chikungunya virus epidemic that occurred on Reunion Island from May 2005 to the end of 2006 affected 30% of the population (more than 250 000 people). As a result of its major clinical impact, this outbreak allowed better documentation of the acute phase of the disease. The disease generally has a slowly self-limiting course over a period of several months with rheumatic manifestations. For practitioners, these symptoms raise numerous questions at several levels, i.e., i) role of the virus in pain, ii) most appropriate treatment, and iii) prevention of development of chronic symptoms. This study in two patient cohorts on Reunion Island was carried out in an attempt to improve understanding and management of chronic rheumatic manifestations following chikungunya virus infection. Findings in 360 patients presenting painful manifestations following chikungunya virus infection showed that the risk of developing inflammatory polyarthritis was higher if the initial acute phase lasted longer than 3 weeks. Based on this observation, it is recommended that these patients undergo rheumatologic evaluation at 3 months to assess the need for possible immunosuppressor treatment (methotrexate).

Trends in healthcare resource use and expenditure before and after ischaemic stroke. A population-based study.

INTRODUCTION: Despite improved survival rates, stroke represents an increasing healthcare and socioeconomic burden. We describe the main characteristics of patients with ischaemic stroke and resource use and associated expenditure one year before and 3 years after stroke, using a population-based dataset. METHODS: The information technology systems of the Catalan Health Service were used to identify patients with ischaemic strokes occurring between January 2012 and December 2016. For each patient, information from one year before the stroke and up to 3 years thereafter was linked across databases. We describe annual and monthly resource use and healthcare expenditure per patient. RESULTS: We identified 36 044 patients with ischaemic stroke (mean age, 74.7 ± 13.3 years). The survival rate at 3 years was 63%. Average expenditure per patient was €3230 the year before stroke, €11 060 for year 1 after stroke, €4104 for year 2, and €3878 for year 3. The greatest determinants of cost in year 1 were hospitalisation (including initial hospitalisation), representing 45% of the difference in expenditure compared to the previous year, and convalescence and rehabilitation services, representing 33% of this difference. After year one, the increase in expenditure was mainly determined by additional hospital admissions and drug treatment. CONCLUSION: After ischaemic stroke, healthcare expenditure increases primarily because of initial hospitalisation. After year one, the expenditure decreases but remains above baseline values. Information from population-based datasets is useful for improving the planning of stroke services.

Patient-related features associated with a delay in seeking care after stroke.

BACKGROUND: Different factors may weight on time from stroke onset to hospital arrival, and patients' alert certainly contributes to it. We sought to identify clinical and sociodemographic factors associated with a delayed alert and to delineate the profile of the potential latecomer in Catalonia (Spain). METHODS: We used data from the Stroke Code (SC) registry that prospectively recruited consecutive patients with acute stroke, in whom SC was activated (SCA) or not (SCNA), admitted to all Catalan hospitals. Additionally, SCNA patients underwent a structured interview to explore additional beliefs and attitudes related to a delayed alert. We applied a 6-h cut-off to define alert delay according to the time limit for SC activation in Catalonia. We determined independent predictors of delay amongst clinical and sociodemographic data by multivariate logistic regression and applied sample weighting because of different study periods in the SCA and SCNA arms. RESULTS: Of the patients, 37.2% delayed alert beyond 6 h. Compared to non-delayers, latecomers were more likely diabetics, illiterates, belonged to an unfavored social class, and were living alone. Fewer had concomitant atrial fibrillation and alerted through emergency medical service (EMS)/112 whilst suffering a mild or moderate stroke. Amongst patients interviewed, being unaware of stroke's vascular nature and erroneously self-perceiving stroke as a reversible or irrelevant condition independently predicted a longer delay. CONCLUSIONS: Delaying alert after stroke shows a multifactorial background with implication of pre-stroke health status, socioeconomic factors, stroke-related features and patients' beliefs and attitudes toward the disease. In planning future educational campaigns, all these features should be considered.

[Grade of consistency existing in the grade of hepatic fibrosis calculated with the APRI and FORNS biochemistry indexes and transient elastography (Fibroscan in patients coinfected with HIV-HCV]. / Estudio de concordancia en el grado de fibrosis hepáticaestimada mediante los índices bioquímicos APRI y FORNS, y la elastografía de transición (Fibroscan((R))) en pacientes coinfectados por VIH-VHC.

INTRODUCTION: There are non-invasive diagnostic methods of liver fibrosis that are based on biochemical measurements (such as APRI or Forns) or on transient elastography. This study aims to compare the consistency between them in patients coinfected by the human immunodeficiency virus and the hepatitis C virus. PATIENTS AND METHODS: An elastography, APRI and Forns were performed for 331 patients to evaluate the consistency between the advanced and low grades of fibrosis. The grades of consistency existing between them were calculated with the kappa coefficient. RESULTS: The grades of fibrosis calculated by APRI and by Forns provided intermediate results (51.1% and 54.7%, respectively), and these patients were not enrolled in the study. The consistency of the elastography in the advanced grade versus the APRI index was 65% and 75% for the Forns index. When the elastography obtained low grade calculations of fibrosis, the consistency with APRI was 80% and 82.2% with Forns Global consistency was 85.5% and with at least one biochemistry index of 72.1%. CONCLUSION: In the HIV and HCV coinfected patients, the use of the APRI and Forns biochemistry indexes to calculate grade of liver fibrosis does not successfully classify at least half of the patients. However, in the patients classified as having high or low fibrosis, the consistency between the calculations obtained by elastography and those derived from the APRI and Forns indexes is moderate to high.

Trends in healthcare resource use and expenditure before and after ischaemic stroke. A population-based study. / Evolución del gasto en servicios sanitarios antes y después del ictus isquémico: análisis de base poblacional.

INTRODUCTION: Despite improved survival rates, stroke represents an increasing healthcare and socioeconomic burden. We describe the main characteristics of patients with ischaemic stroke and resource use and associated expenditure one year before and 3 years after stroke, using a population-based dataset. METHODS: The information technology systems of the Catalan Health Service were used to identify patients with ischaemic strokes occurring between January 2012 and December 2016. For each patient, information from one year before the stroke and up to 3 years thereafter was linked across databases. We describe annual and monthly resource use and healthcare expenditure per patient. RESULTS: We identified 36,044 patients with ischaemic stroke (mean age, 74.7±13.3 years). The survival rate at 3 years was 63%. Average expenditure per patient was €3,230 the year before stroke, €11,060 for year one after stroke, €4,104 for year 2, and €3,878 for year 3. The greatest determinants of cost in year one were hospitalisation (including initial hospitalisation), representing 45% of the difference in expenditure compared to the previous year, and convalescence and rehabilitation services, representing 33% of this difference. After year one, the increase in expenditure was mainly determined by additional hospital admissions and drug treatment. CONCLUSION: After ischaemic stroke, healthcare expenditure increases primarily because of initial hospitalisation. After year one, the expenditure decreases but remains above baseline values. Information from population-based datasets is useful for improving the planning of stroke services.

A potassium channel gene is expressed at neural induction.

Voltage-dependent potassium currents exhibit specific time tables of functional differentiation and regulate the development of action potentials in amphibian spinal neurons. A Xenopus nucleotide sequence (XSha2) encoding a potassium current has been isolated by homology screening with the Drosophila Shaker gene. Functional expression in oocytes identifies it as a delayed rectifier. Southern analysis suggests that XSha2 is a member of a family of highly related genes. XSha2 is expressed in the nervous system but is not detectable in skeletal muscle. Transcripts are apparent at the neural fold stage, and subsequent levels parallel those of the neural marker N-CAM. Thus molecular events required for the establishment of electrical excitability in the vertebrate embryo occur early during neurogenesis.

A critical period of transcription required for differentiation of the action potential of spinal neurons.

The early development of excitability of amphibian spinal neurons is characterized by a change from a long Ca2(+)-dependent action potential to a brief Na(+)-dependent impulse. The delayed rectifier K+ current plays a major role in this cell autonomous differentiation. Here we show that the maturation of the delayed rectifier current, and hence the action potential, involves a critical period of mRNA synthesis. It is blocked by inhibition of transcription during an early period of development in culture and fails to develop following removal of the inhibitor and resumption of RNA synthesis. However, the development of an inactivating K+ A-current recovers in these neurons, indicating that some programs of neuronal development are affected during this critical period, while others are spared.

False extended-spectrum beta-lactamase detection in Acinetobacter spp. due to intrinsic susceptibility to clavulanic acid.

BACKGROUND: There are some reports showing the susceptibility of some strains of Acinetobacter baumannii to the beta-lactamase inhibitor clavulanic acid. To address this issue, we determined the MIC of clavulanic acid for a broad collection of Acinetobacter spp. isolates collected in a multicentre study. In addition, we showed the consequences of this susceptibility to yield false extended-spectrum beta-lactamase (ESBL) detection in this genus. METHODS: The strains used were 244 isolates of Acinetobacter (226 A. baumannii, 15 Acinetobacter genomic species 3 and 3 unidentified Acinetobacter spp.) and several A. baumannii as positive controls. The isolates were subjected to molecular typing. One isolate of each genotype was subjected to clavulanic acid MIC analysis. As no breakpoints for clavulanic acid are available, we arbitrarily established three categories of susceptibility: < or = 16, 32-128 and > or = 256 mg/L. The presence of ESBL in Acinetobacter spp. was analysed by using microdilution, double disc diffusion, combined discs, Etest and isoelectric focusing. RESULTS: A total of 100 different genotypes were detected. Among them, 44, 26 and 30 genotypes were inhibited by < or = 16, 32-128 and > or = 256 mg/L clavulanic acid, respectively. Representative isolates of each group were tested for ESBL production. Only those with the lower clavulanic acid MICs yielded a false-positive ESBL test with all methods tested with the exception of the double disc diffusion assay. CONCLUSIONS: Forty-four per cent of the genotypes tested were inhibited by < or = 16 mg/L clavulanic acid and these Acinetobacter isolates yielded a false ESBL-positive test. These results may have implications for susceptibility testing in routine microbiology laboratories.

Synaptic activity modulates presynaptic excitability.

Synaptic activity modulates synaptic efficacy and is important in learning and development. Here we show that development of excitability in presynaptic motor neurons required synaptic activation of postsynaptic muscle cells. Synaptic blockade broadened action potentials and decreased repetitive firing of presynaptic neurons. Consistent with these findings, synaptic blockade also decreased potassium-current density in the presynaptic cell. Application of neurotrophin-3, but not related neurotrophins, prevented these changes. Recordings from patches of somatic membrane indicated that modifications of presynaptic potassium and sodium currents occurred in a remote, nonsynaptic compartment. Thus, activity-dependent postsynaptic signals modulated presynaptic excitability, potentially regulating transmission at all synapses of the presynaptic cell.

Impact of Staphylococcus aureus phenotype and genotype on the clinical characteristics and outcome of infective endocarditis. A multicentre, longitudinal, prospective, observational study.

OBJECTIVE: We aimed to evaluate the impact of Staphylococcus aureus phenotype (vancomycin MIC) and genotype (agr group, clonal complex CC) on the prognosis and clinical characteristics of infective endocarditis (IE). METHODS: We performed a multicentre, longitudinal, prospective, observational study (June 2013 to March 2016) in 15 Spanish hospitals. Two hundred and thirteen consecutive adults (≥18 years) with a definite diagnosis of S. aureus IE were included. Primary outcome was death during hospital stay. Main secondary end points were persistent bacteraemia, sepsis/septic shock, peripheral embolism and osteoarticular involvement. RESULTS: Overall in-hospital mortality was 37% (n = 72). Independent risk factors for death were age-adjusted Charlson co-morbidity index (OR 1.20; 95% CI 1.08-1.34), congestive heart failure (OR 3.60; 95% CI 1.72-7.50), symptomatic central nervous system complication (OR 3.17; 95% CI 1.41-7.11) and severe sepsis/septic shock (OR 4.41; 95% CI 2.18-8.96). In the subgroup of methicillin-susceptible S. aureus IE (n = 173), independent risk factors for death were the age-adjusted Charlson co-morbidity index (OR 1.17; 95% CI 1.03-1.31), congestive heart failure (OR 3.39; 95% CI 1.51-7.64), new conduction abnormality (OR 4.42; 95% CI 1.27-15.34), severe sepsis/septic shock (OR 5.76; 95% CI 2.57-12.89) and agr group III (OR 0.27; 0.10-0.75). Vancomycin MIC ≥1.5 mg/L was not independently associated with death during hospital nor was it related to secondary end points. No other genotype variables were independently associated with in-hospital death. CONCLUSIONS: This is the first prospective study to assess the impact of S. aureus phenotype and genotype. Phenotype and genotype provided no additional predictive value beyond conventional clinical characteristics. No evidence was found to justify therapeutic decisions based on vancomycin MIC for either methicillin-resistant or methicillin-susceptible S. aureus.

A pragmatic approach for mortality prediction after surgery in infective endocarditis: optimizing and refining EuroSCORE.

OBJECTIVE: To simplify and optimize the ability of EuroSCORE I and II to predict early mortality after surgery for infective endocarditis (IE). METHODS: Multicentre retrospective study (n = 775). Simplified scores, eliminating irrelevant variables, and new specific scores, adding specific IE variables, were created. The performance of the original, recalibrated and specific EuroSCOREs was assessed by Brier score, C-statistic and calibration plot in bootstrap samples. The Net Reclassification Index was quantified. RESULTS: Recalibrated scores including age, previous cardiac surgery, critical preoperative state, New York Heart Association >I, and emergent surgery (EuroSCORE I and II); renal failure and pulmonary hypertension (EuroSCORE I); and urgent surgery (EuroSCORE II) performed better than the original EuroSCOREs (Brier original and recalibrated: EuroSCORE I: 0.1770 and 0.1667; EuroSCORE II: 0.2307 and 0.1680). Performance improved with the addition of fistula, staphylococci and mitral location (EuroSCORE I and II) (Brier specific: EuroSCORE I 0.1587, EuroSCORE II 0.1592). Discrimination improved in specific models (C-statistic original, recalibrated and specific: EuroSCORE I: 0.7340, 0.7471 and 0.7728; EuroSCORE II: 0.7442, 0.7423 and 0.7700). Calibration improved in both EuroSCORE I models (intercept 0.295, slope 0.829 (original); intercept -0.094, slope 0.888 (recalibrated); intercept -0.059, slope 0.925 (specific)) but only in specific EuroSCORE II model (intercept 2.554, slope 1.114 (original); intercept -0.260, slope 0.703 (recalibrated); intercept -0.053, slope 0.930 (specific)). Net Reclassification Index was 5.1% and 20.3% for the specific EuroSCORE I and II. CONCLUSIONS: The use of simplified EuroSCORE I and EuroSCORE II models in IE with the addition of specific variables may lead to simpler and more accurate models.

Hybrid magnetite-gold nanoparticles as bifunctional magnetic-plasmonic systems: three representative cases.

Hybrid systems based on magnetite and gold nanoparticles have been extensively used as bifunctional materials for bio- and nano-technology. The properties of these composites are assumed to be closely related to the magnetite to gold mass ratio and to the geometry of the resulting hetero-structures. To illustrate this, we compare and analyze the optical and magnetic properties of core-shell, dumbbell-like dimers and chemical cross-linked pairs of magnetite and gold nanoparticles in detail. We explore how the combination of gold with magnetite can lead to an improvement of the optical properties of these systems, such as tunability, light scattering enhancement or an increase of the local electric field at the interface between magnetic and plasmonic constituents. We also show that although the presence of gold might affect the magnetic response of these hybrid systems, they still show good performance for magnetic applications; indeed the resulting magnetic properties are more dependent on the NP size dispersion. Finally, we identify technological constraints and discuss prospective routes for the development of further magnetic-plasmonic materials.

Fe3O4@Au@mSiO2 as an enhancing nanoplatform for Rose Bengal photodynamic activity.

A novel nanoplatform composed of three types of materials with different functionalities, specifically core-shell Fe3O4@Au nanoparticles encapsulated near the outer surface of mesoporous silica (mSiO2) nanoparticles, has been successfully synthesised and used to enhance the efficiency of a photosensitiser, namely Rose Bengal, in singlet oxygen generation. Fe3O4 is responsible for the unusual location of the Fe3O4@Au nanoparticle, while the plasmonic shell acts as an optical antenna. In addition, the mesoporous silica matrix firmly encapsulates Rose Bengal by chemical bonding inside the pores, thus guaranteeing its photostability, and in turn making the nanosystem biocompatible. Moreover, the silica surface of the nanoplatform ensures further functionalisation on demand.

Time trends in the aetiology of prosthetic joint infections: a multicentre cohort study.

It is important to know the spectrum of the microbial aetiology of prosthetic joint infections (PJIs) to guide empiric treatment and establish antimicrobial prophylaxis in joint replacements. There are no available data based on large contemporary patient cohorts. We sought to characterize the causative pathogens of PJIs and to evaluate trends in the microbial aetiology. We hypothesized that the frequency of antimicrobial-resistant organisms in PJIs has increased in the recent years. We performed a cohort study in 19 hospitals in Spain, from 2003 to 2012. For each 2-year period (2003-2004 to 2011-2012), the incidence of microorganisms causing PJIs and multidrug-resistant bacteria was assessed. Temporal trends over the study period were evaluated. We included 2524 consecutive adult patients with a diagnosis of PJI. A microbiological diagnosis was obtained for 2288 cases (90.6%). Staphylococci were the most common cause of infection (1492, 65.2%). However, a statistically significant rising linear trend was observed for the proportion of infections caused by Gram-negative bacilli, mainly due to the increase in the last 2-year period (25% in 2003-2004, 33.3% in 2011-2012; p 0.024 for trend). No particular species contributed disproportionally to this overall increase. The percentage of multidrug-resistant bacteria PJIs increased from 9.3% in 2003-2004 to 15.8% in 2011-2012 (p 0.008), mainly because of the significant rise in multidrug-resistant Gram-negative bacilli (from 5.3% in 2003-2004 to 8.2% in 2011-2012; p 0.032). The observed trends have important implications for the management of PJIs and prophylaxis in joint replacements.