The association between the weight of schoolbags and low back pain among schoolchildren: A systematic review, meta‐analysis and individual patient data meta‐analysis

[EN] Background The objective of this study was to determine whether carrying a heavy schoolbag is associated to a higher prevalence of low back pain (LBP). Methods A systematic review and meta-analysis was conducted (PROSPERO, CRD42018077839). Observational studies analysing the relationship between schoolbag weight and LBP, were searched for in 20 electronic databases and 12 specialized journals until February 28th, 2019, without date or language restrictions. All studies which included ≥ 50 subjects aged 9 to 16, were reviewed. Methodological quality was assessed by two reviewers separately, using validated tools. A meta-analysis and an individual patient data (IPD) meta-analysis were conducted to examine the relationship between schoolbag weight and LBP. Certainty of evidence was assessed using an adapted GRADE methodology. Results 5,524 citations were screened, 21 studies (18,296 subjects) were reviewed and 11 studies (9,188 subjects) were included in the meta-analysis. The IPD meta-analysis included 9,188 subjects from seven studies. Among the 21 studies reviewed, the mean score for methodological quality was 78.3 of 100. Only one study suggested an association between heavier schoolbags and LBP. Neither the meta-analysis nor the IPD meta-analysis found an association between carrying schoolbags weighing > 10% of bodyweight, and LBP. No differences based on age, gender or sport activity were found. Discussion Available evidence does not support that schoolbags weighing > 10% of bodyweight are associated with a higher prevalence of LBP among schoolchildren aged 9–16. The certainty of evidence is low. Further research is required on the relationship between schoolbag weight and LBP. Significance This systematic review, with a meta-analysis and an IPD meta-analysis, failed to find a link between schoolbags weighing ≥ 10% of body weight and LBP among schoolchildren aged 9 to 16. Further longitudinal studies, with large samples, long follow-up periods, and rigorous methods taking into account duration of carry and the physical capacity of each subject, are required in this field.S

Altered Plasma and Brain Disposition and Pharmacodynamics of Methadone in Abstinent Rats

The pharmacokinetics and pharmacodynamics of methadone were investigated in control and abstinent rats. Minipumps filled with saline (control group) or saline-morphine (abstinent group) solutions were used to induce physical dependence. Solutions were delivered continuously by minipumps for 6 days. The physical dependence was evaluated 12 h after minipump removal by measuring specific withdrawal signs. Animals from the abstinent group showed clear withdrawal signs such as hostility on handling and weight loss. Plasma and brain disposition and pharmacodynamics of methadone were evaluated after a 0.35 mg/kg i.v. bolus dose administered 12 h after minipump removal. Plasma clearance, distribution clearance, and volume of distribution at steady-state were significantly decreased (P < 0.05) in the abstinent group. Plasma levels of alpha1-acid glycoprotein and plasma protein binding were significantly increased (P < 0.05) in the abstinent group. The estimates of pharmacokinetic parameters based on unbound plasma concentrations did not differ between groups, with the sole exception of the unbound apparent volume of distribution. The access of methadone to the brain was significantly faster (P < 0.05) in the abstinent group, although the extent of distribution in the brain was diminished in comparison with the control group. Analgesia recorded with tail-flick was used as the pharmacodynamic endpoint. Analgesic response and effect compartment concentrations of methadone were related by the sigmoidal Emax model. Estimates of C50 [steady-state plasma concentrations eliciting half of maximum effect (Emax)]] based on unbound concentrations did not differ between groups. On the other hand, the estimate of Emax had decreased by 65% in the abstinent group

Serum PCB levels in a representative sample of the Spanish adult population: the BIOAMBIENT.ES project

This manuscript presents the levels of six indicator polychlorinated biphenyl (PCB) congeners (IUPAC nos. 28, 52, 101, 138, 153 and 180) in the serum of 1880 individuals from a representative sample of the Spanish working population recruited between March 2009 and July 2010. Three out of the six PCBs studied (180, 153 and 138) were quantified in more than 99% of participants. PCB 180 was the highest contributor, followed by PCBs 153 and 138, with relative abundances of 42.6%, 33.2% and 24.2%, respectively. In contrast, PCBs 28 and 52 were detected in only 1% of samples, whereas PCB 101 was detectable in 6% of samples. The geometric mean (GM) for ΣPCBs138/153/180 was 135.4 ng/g lipid (95% CI: 121.3-151.2 ng/g lipid) and the 95th percentile was 482.2 ng/g lipid. Men had higher PCB blood concentrations than women (GMs 138.9 and 129.9 ng/g lipid respectively). As expected, serum PCB levels increased with age and frequency of fish consumption, particularly in those participants younger than 30 years of age. The highest levels we found were for participants from the Basque Country, whereas the lowest concentrations were found for those from the Canary Islands. The Spanish population studied herein had similar levels to those found previously in Greece and southern Italy, lower levels than those in France and central Europe, and higher PCB levels than those in the USA, Canada and New Zealand. This paper provides the first baseline information regarding PCB exposure in the Spanish adult population on a national scale. The results will allow us to establish reference levels, follow temporal trends and identify high-exposure groups, as well as monitor implementation of the Stockholm Convention in Spain.This work was funded as part of a research agreement between the Spanish Ministry of Agriculture, Food and the Environment n° EG042007 and the Institute of Health Carlos III (project nos. SEG 1251/07 and 1210/10). The authors would like to thank S. González for the technical assistance, F. Cutanda for the helpful advice, and Silvia Gómez; the volunteers of BIOAMBIENT.ES and healthcare staff from the Societies for Prevention of IBERMUTUAMUR, MUTUALIA, MCPREVENCIÓN, MUGATRA, UNIMAT PREVENCIÓN, and PREVIMAC

Polarització, espectacularització, tertúlies i periodisme. Una visió comunicativa del procés català

Obra col·lectiva biennal, creada per l'Institut de la Comunicació de la Universitat Autònoma de Barcelona (InCom-UAB), l'any 2000. La desena edició, corresponent al bienni 2017-2018, va comptar amb el suport de la Generalitat de Catalunya; el patrocini de Naturgy; la col·laboració de l'Ajuntament de Barcelona; la subscripció institucional de la Societat Catalana de Comunicació (filial de l'Institut d'Estudis Catalans); i la col·laboració científica de Comscore, Estudio General de Medios (EGM)/Asociación para la Investigación de Medios de Comunicación (AIMC), l'Observatori de la Comunicació a Catalunya, i el Portal de la Comunicació (InCom-UAB).En el marc del Grup Internacional d'Estudis sobre Comunicació i Cultura (InCom-UAB), reconegut com a Grup Consolidat de Recerca de la Generalitat de Catalunya per al període 2017-2020 (Referència de concessió 2017 SGR 00760).La polarització discursiva, la mediatització i l'espectacularització de la política, el paper dels gèneres opinatius en la construcció de l'opinió pública catalana -amb especial rellevància el de la tertúlia o la crisi de legitimitat del sistema mediàtic del territori són algunes qüestions que han condicionat el context polític i social si posem el focus en els aspectes comunicatius del procés català. També cal destacar la crisi generada en la relació entre periodistes, polítics i ciutadania. Aquesta crisi ha trencat el sempre precari equilibri entre tres actors bàsics de la deliberació pública i ha intensificat, seguint una tendència global, una lluita per la legitimitat i la consolidació de la professió periodística com a pilar central de la salut del nostre sistema democràtic. El reforç i reconeixement a la tasca dels periodistes seran especialment necessaris davant d'estratègies evidents per fer-se amb el control i la difusió de la informació política en el conflicte català

Recerca en comunicació i procés català

Obra col·lectiva biennal, creada per l'Institut de la Comunicació de la Universitat Autònoma de Barcelona (InCom-UAB), l'any 2000. La desena edició, corresponent al bienni 2017-2018, va comptar amb el suport de la Generalitat de Catalunya; el patrocini de Naturgy; la col·laboració de l'Ajuntament de Barcelona; la subscripció institucional de la Societat Catalana de Comunicació (filial de l'Institut d'Estudis Catalans); i la col·laboració científica de Comscore, Estudio General de Medios (EGM)/Asociación para la Investigación de Medios de Comunicación (AIMC), l'Observatori de la Comunicació a Catalunya, i el Portal de la Comunicació (InCom-UAB).En el marc del Grup Internacional d'Estudis sobre Comunicació i Cultura (InCom-UAB), reconegut com a Grup Consolidat de Recerca de la Generalitat de Catalunya per al període 2017-2020 (Referència de concessió 2017 SGR 00760).Al present capítol es fa una revisió de la recerca en comunicació elaborada durant aquests anys convulsos, on el procés o conflicte català ha esdevingut un mirall excepcional per copsar dinàmiques discursives; relacions entre periodistes, mitjans de comunicació, polítics i ciutadania; característiques i mutacions del sistema mediàtic; l'impacte de les xarxes socials en l'articulació del conflicte; el rol de la premsa estrangera en la construcció mediàtica de la crisi, o la tendència a l'espectacularització de la política i les seves implicacions en termes de salut democràtica

Pharmacokinetic-pharmacodynamic modeling of the antinociceptive effects of main active metabolites of tramadol, (+)-O-desmethyltramadol and (-)-O-desmethyltramadol, in rats.

The pharmacokinetics and pharmacodynamics of the two main metabolites of tramadol, (+)-O-desmethyltramadol and (-)-O-desmethyltramadol, were studied in rats. Pharmacodynamic endpoints evaluated were respiratory depression, measured as the change in arterial blood pCO(2), pO(2), and pH levels; and antinociception, measured by the tail-flick technique. The administration of 10 mg/kg (+)-O-desmethyltramadol in a 10-min i.v. infusion significantly altered pCO(2), pO(2), and pH values in comparison with baseline and lower-dose groups (P <.05). However, 2 mg/kg administered in a 10-min i.v. infusion was enough to achieve 100% antinociception without respiratory depression. Moreover, the beta-funaltrexamine pretreatment completely eliminated the antinociception of the 2-mg/kg dose, suggesting that such an effect is due to mu-opioid receptor activation. To describe and adequately characterize the in vivo antinociceptive effect of the drug, (+)-O-desmethyltramadol was given at different infusion rates of varying lengths (10-300 min). Pharmacokinetics was best described by a two-compartmental model. The time course of response was described using an effect compartment associated with a linear pharmacodynamic model. The estimates of the slope of the effect versus concentration relationship were significantly decreased (P <. 05) as the length of infusion was increased, suggesting the development of tolerance. Doses of up to 8 mg/kg (-)-O-desmethyltramadol given in 10-min i.v. infusion did not elicit either antinociception in the tail-flick test or respiratory effects. These in vivo results are in accordance with the opiate and nonopiate properties reported for these compounds in several in vitro studies

Recent advances in the particle finite element method. Towards more complex fluid flow applications

One of the main drawbacks of the explicit integration using Eulerian formulations is the restricted stability of the solution with the time steps and with the spatial discretization. For the case of the Navier-Stokes equations, it is well known that the time step to be used in the solution is stable only for time step smaller than two critical values: the Courant- Friedrichs-Lewy (CFL) number and the Fourier number. The first one is concerning with the convective terms and the second one with the diffusive ones. Both numbers must be less than one to have stable algorithms. For convection dominant problems like high Reynolds number flows, the condition CFL<1 becomes crucial and limit the use of explicit method or outdistance it to be efficient. On the other hand, implicit solutions using Eulerian formulations is restricted in the time step size due to the lack of convergence of the convective non-linear terms. Both time integrations, explicit or implicit are, in most cases, limited to CFL no much larger than one. The possibility to perform parallel processing and the recent upcoming of new processors like GPU and GPGPU increase the possibilities of the explicit integration in time due to the facility to parallelize explicit methods having results with speedup closed to one. Although the incompressible condition cannot be solved explicitly, the solution of the momentum conservation equations with an explicit integration of the convective terms together with a parallel processing reduces considerably the computing time to solve the whole problem provided that a large time-step may be preserved independently to the discretization in space. Only to remember the new Particle Finite Element Method, called PFEM 2nd generation (PFEM-2) uses a Lagrangian formulation with an explicit time integrator without the CFL<1 restriction for the convective terms. This allows large timesteps, independent of the spatial discretization, having equal or better precision that an implicit integration. Moreover, PFEM-2 has two versions, one for moving mesh with permanent remeshing and one for fixed mesh [1]. In this lecture we will present some recent advances in the Particle Finite Element Method (PFEM) to solve the incompressible Navier- Stokes equations coupled with another fields like in multiphysics exploiting some nice features found in the fixed version. On the other hand we will also present the moving mesh version applied to multifluids using a parallel remeshing that makes this efficient in terms of cpu time. This updated proposal will be tested numerically and compared in terms of accuracy as in computing cpu time with other more standard Eulerian formulations

Modeling of the In Vivo Antinociceptive Interaction between an Opioid Agonist, (+)-O-Desmethyltramadol, and a Monoamine Reuptake Inhibitor, (—)-O-Desmethyltramadol, in Rats

The pharmacokinetic-pharmacodynamic (pk-pd) characterization of the in vivo antinociceptive interaction between (+)-O-desmethyltramadol [(+)-M1] and (-)-O-desmethyltramadol [(-)-M1], main metabolites of tramadol, was studied in three groups of rats. (+)-M1 and (-)-M1, both with different pd properties, were studied under steady-state and nonsteady-state conditions, depending on the group. Plasma drug concentration and antinociception were simultaneously measured in each animal by using an enantioselective analytical assay and the tail-flick test, respectively. Respiratory depression also was evaluated in another series of experiments according to the same experimental conditions. The pk behavior was similar for both enantiomers and no significant (P >.05) interaction between two compounds was found at this level. However, a significant (P .05) respiratory effects were seen during or after (+)-M1 and (-)-M1 administration

Influence of a gel emulsion containing microalgal oil and a blackthorn (Prunus spinosa L.) branch extract on the antioxidant capacity and acceptability of reduced fat beef patties

The addition of a blackthorn branch extract (Prunus spinosa L.) to a gel emulsion system containing microalgal oil was examined in order to obtain a functional ingredient (APG), for use as fat replacer in beef patties. Chromatographic analysis indicated that catechins were the major polyphenols present in the Prunus spinosa L. extract. The antioxidant capacity increased as a result of the extract addition, as shown by the comparison of the gel emulsions, with and without it (APG and AG, respectively). Beef patties containing APG as fat replacer (modified patties) had a lower fat content (5.3% versus 10.75%), doubled the antioxidant activity and the DHA content, and improved the stability against oxidation by reducing the peroxide content more than two fold when compared to control patties. In addition, instrumental color measured by the CIE L*a*b* system showed no significant difference between control and modified raw patties. Moreover, the sensory acceptability of the new formulation was confirmed by a like/dislike hedonic test

Toward Telemonitoring in Immune-Mediated Inflammatory Diseases: Protocol for a Mixed Attention Model Study

Mixed attention model; Rheumatic musculoskeletal diseases; TelemonitoringModelo de atención mixta; Enfermedades musculoesqueléticas reumáticas; TelevigilanciaModel d'atenció mixta; Malalties musculoesquelètiques reumàtiques; TelevigilànciaBackground: Rheumatic and musculoskeletal diseases (RMDs) are chronic diseases that may alternate between asymptomatic periods and flares. These conditions require complex treatments and close monitoring by rheumatologists to mitigate their effects and improve the patient’s quality of life. Often, delays in outpatient consultations or the patient’s difficulties in keeping appointments make such close follow-up challenging. For this reason, it is very important to have open communication between patients and health professionals. In this context, implementing telemonitoring in the field of rheumatology has great potential, as it can facilitate the close monitoring of patients with RMDs. The use of these tools helps patients self-manage certain aspects of their disease. This could result in fewer visits to emergency departments and consultations, as well as enable better therapeutic compliance and identification of issues that would otherwise go unnoticed. Objective: The main objective of this study is to evaluate the implementation of a hybrid care model called the mixed attention model (MAM) in clinical practice and determine whether its implementation improves clinical outcomes compared to conventional follow-up. Methods: This is a multicenter prospective observational study involving 360 patients with rheumatoid arthritis (RA) and spondylarthritis (SpA) from 5 Spanish hospitals. The patients will be followed up by the MAM protocol, which is a care model that incorporates a digital tool consisting of a mobile app that patients can use at home and professionals can review asynchronously to detect incidents and follow patients' clinical evolution between face-to-face visits. Another group of patients, whose follow-up will be conducted in accordance with a traditional face-to-face care model, will be assessed as the control group. Sociodemographic characteristics, treatments, laboratory parameters, assessment of tender and swollen joints, visual analog scale for pain, and electronic patient-reported outcome (ePRO) reports will be collected for all participants. In the MAM group, these items will be self-assessed via both the mobile app and during face-to-face visits with the rheumatologist, who will do the same for patients included in the traditional care model. The patients will be able to report any incidence related to their disease or treatment through the mobile app. Results: Participant recruitment began in March 2024 and will continue until December 2024. The follow-up period will be extended by 12 months for all patients. Data collection and analysis are scheduled for completion in December 2025. Conclusions: This paper aims to provide a detailed description of the development and implementation of a digital solution, specifically an MAM. The goal is to achieve significant economic and psychosocial impact within our health care system by enhancing control over RMDs.This work was supported by: Fondo para la Investigación Sanitaria, Instituto de Salud Carlos III (PI22/00777)