496 research outputs found

    Moving from phenomenological to predictive modelling: Progress and pitfalls of modelling brain stimulation in-silico

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    Brain stimulation is an increasingly popular neuromodulatory tool used in both clinical and research settings; however, the effects of brain stimulation, particularly those of non-invasive stimulation, are variable. This variability can be partially explained by an incomplete mechanistic understanding, coupled with a combinatorial explosion of possible stimulation parameters. Computational models constitute a useful tool to explore the vast sea of stimulation parameters and characterise their effects on brain activity. Yet the utility of modelling stimulation in-silico relies on its biophysical relevance, which needs to account for the dynamics of large and diverse neural populations and how underlying networks shape those collective dynamics. The large number of parameters to consider when constructing a model is no less than those needed to consider when planning empirical studies. This piece is centred on the application of phenomenological and biophysical models in non-invasive brain stimulation. We first introduce common forms of brain stimulation and computational models, and provide typical construction choices made when building phenomenological and biophysical models. Through the lens of four case studies, we provide an account of the questions these models can address, commonalities, and limitations across studies. We conclude by proposing future directions to fully realise the potential of computational models of brain stimulation for the design of personalized, efficient, and effective stimulation strategies

    Development and validation of a Medication Adherence Universal Questionnaire: the MAUQ

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    Abstract Background Different questionnaires assess self-reported medication adherence and others quantify aspects of patients attitudes towards medication, but not together in a single instrument. Gathering these two aspects in a single instrument could reduce patients survey burden. Aim The aim of this study was to develop the Medication Adherence Universal Questionnaire (MAUQ) using the Maastricht Utrecht Adherence in Hypertension short version (MUAH-16) factorial structure as the hypothesized model. Method A multistep process started with the modification of the MUAH-16 to obtain the MAUQ. Patients using at least one antihypertensive medicine were recruited. The two questionnaires, the MUAH-16 and MAUQ, were applied. A confirmatory factor analysis (CFA) was performed using the initial MUAH-16 s-order 4-factor model. An additional bifactor model with four uncorrelated factors and an overall score was tested. The comparative fit index (CFI), root mean square error of approximation (RMSEA) with confidence intervals (CIs), and standardized root mean squared residual (SRMR) were used to assess both models. Results A sample of 300 hypertensive patients completed the instruments. The CFA with the second-order 4-factor solution resulted in similar results for the MUAH-16 and MAUQ: CFIs of 0.934 and 0.930, RMSEAs of 0.043 [CI 0.0300.056] and 0.045 [CI 0.0310.057] and SRMRs of 0.060 and 0.061, respectively. The CFA with the bifactor model showed slightly better results for both the MUAH-16 and MAUQ: CFIs of 0.974 and 0.976, RMSEAs of 0.030 [CI 0.0050.046] and 0.028 [CI 0.0010.044], and SRMRs of 0.043 and 0.044, respectively. Conclusion CFA demonstrated that the MAUQ presented a better fit to both models than the MUAH-16, obtaining a robust universal free instrument to assess medicine-taking behaviour and four medicine beliefs components. </jats:sec

    Tectonic and lithological controls on fluvial landscape development in Central-Eastern Portugal: Insights from long profile tributary stream analyses

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    This study examines the long profiles of tributaries of the Tagus and Zêzere rivers in Portugal (West Iberia) in order to provide new insights into patterns, timing, and controls on drainage development during the Quaternary incision stage. The studied streams are incised into a relict culminant fluvial surface, abandoned at the beginning of the incision stage. The streams flow through a landscape with bedrock variations in lithology (mainly granites and metasediments) and faulted blocks with distinct uplift rates. The long profiles of the analyzed streams record an older transitory knickpoint/knickzone separating (1) an upstream relict graded profile, with lower steepness and higher concavity, that reflects a long period of quasi-equilibrium conditions reached after the beginning of the incision stage, and (2) a downstream rejuvenated long profile, with steeper gradient and lower concavity, particularly for the final reach, which is often convex. The rejuvenated reaches testify to the upstream propagation of several incision waves, interpreted as the response of each stream to increasing crustal uplift and prolonged periods of base-level lowering by the trunk drainages, coeval with low sea level conditions. The morphological configurations of the long profiles enabled spatial and relative temporal patterns of incisions to be quantified. The incision values of streams flowing on the Portuguese Central Range (PCR; ca. 380–150 m) are variable but generally higher than the incision values of streams flowing on the adjacent South Portugal Planation Surface (SPPS; ca. 220–110 m), corroborating differential uplift of the PCR relative to the SPPS. Owing to the fact that the relict graded profiles can be correlated with the Tagus River T1 terrace (1.1–0.9 My) present in the study area, incision rates can be estimated (1) for the streams located in the PCR, 0.38–0.15 m/ky and (2) for the streams flowing on the SPPS, 0.22–0.12 m/ky. The differential uplift inferred in the study area supports the neotectonic activity of the bordering faults, as proposed in previous studies based upon other geological evidence

    Maternal smoking: a life course blood pressure determinant?

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    Introduction: Exposure to maternal smoking early in life may affect blood pressure (BP) control mechanisms. We examined the association between maternal smoking (before conception, during pregnancy, and 4 years after delivery) and BP in preschool children. Methods: We evaluated 4295 of Generation XXI children, recruited at birth in 2005–2006 and reevaluated at the age of 4. At birth, information was collected by face-to-face interview and additionally abstracted from clinical records. At 4-year follow-up, interviews were performed and children’s BP measured. Linear regression models were fitted to estimate the association between maternal smoking and children’s BP. Results: Children of smoking mothers presented significantly higher BP levels. After adjustment for maternal education, gestational hypertensive disorders, and child’s body mass index, children exposed during pregnancy to maternal smoking presented a higher systolic BP (SBP) z-score (β = 0.08, 95% confidence interval [CI] 0.04 to 0.14). In crude models, maternal smoking was associated with higher SBP z-score at every assessed period. However, after adjustment, an attenuation of the association estimates occurred (β = 0.08, 95% CI 0.03 to 0.13 before conception; β = 0.07, 95%CI 0.02 to 0.12; β = 0.04, 95%CI −0.02 to 0.10; and β = 0.06, 95%CI 0.00 to 0.13 for the first, second, and third pregnancy trimesters, respectively; and β = 0.07, 95%CI 0.02 to 0.12 for current maternal smoking). No significant association was observed for diastolic BP z-score levels. Conclusion: Maternal smoking before, during, and after pregnancy was independently associated with systolic BP z-score in preschool children. This study provides additional evidence to the public health relevance of maternal smoking cessation programs if early cardiovascular health of children is envisaged. Implications: Using observational longitudinal data from the birth cohort Generation XXI, this study showed that exposure to maternal smoking—before pregnancy, during pregnancy, and 4 years after delivery—was associated with a systolic BP-raising effect in children at the age of 4. The findings of this study add an important insight into the need to support maternal smoke-free environments in order to provide long-term cardiovascular benefit, starting as early as possible in life.Generation XXI has been funded by the Operational Health Programme XXI Health, Community support framework III (co-funded by Feder), Administração Regional de Saúde do Norte, Fundação Calouste Gulbenkian and Fundação para a Ciência e Tecnologia (SFRH/BSAB/113778/2015; PD/BD/105824/2014; PD/BD/105827/2014; F-COMP-01-0124-FEDER-011008; FCT—PTDC/SAU-ESA/105033/2008). Also, the Portuguese Foundation for Science and Technology funds the Epidemiology Research Unit of the Institute of Public Health of the University of Porto (UID/DTP/04750/2013). This article is a result of the project DOCnet (NORTE-01-0145-FEDER-000003), supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF)

    A Universal Pharmacological-Based List of Drugs with Anticholinergic Activity

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    Anticholinergic burden tools have relevant pharmacological gaps that may explain their limited predictive ability for clinical outcomes. The aim of this study was to provide a universal pharmacological-based list of drugs with their documented affinity for muscarinic receptors. A comprehensive literature review was performed to identify the anticholinergic burden tools. Drugs included in these instruments were searched in four pharmacological databases, and the investigation was supplemented with PubMed. The evidence regarding the potential antagonism of the five muscarinic receptors of each drug was assessed. The proportion of drugs included in the tools with an affinity for muscarinic receptors was evaluated. A universal list of drugs with anticholinergic activity was developed based on their documented affinity for the different subtypes of muscarinic receptors and their ability to cross the blood-brain barrier. A total of 23 tools were identified, including 304 different drugs. Only 48.68%, 47.70%, 48.03%, 43.75%, and 42.76% of the drugs had an affinity to the M1, M2, M3, M4, and M5 receptor, respectively, reported in any pharmacological database. The proportion of drugs with confirmed antagonism varied among the tools (36.8% to 100%). A universal pharmacological-based list of 133 drugs is presented. It should be further validated in different clinical settings. (c) 2023 by the authors

    Bone Densitometry Versus Bone Histomorphometry in Renal Transplanted Patients: A Cross‐Sectional Study

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    Bone loss leads to increase risk of fractures in renal transplantation. The aim of this study was to analyse the relationship between bone densitometry (DXA) findings, bone histomorphometry and bone-related molecules 1-year after renal transplantation. We performed a cross-sectional study of de novo renal transplanted patients that agreed to perform a bone biopsy and a DXA examination 1 year after transplantation. All patients underwent a laboratory evaluation, bone biopsy, DXA examination and cardiac CT 1 year after transplantation. 67 patients were included, 16 had a normal examination, and 18 patients were classified as having osteoporosis by DXA. Correlations between bone mineral density and T-scores of total femur and femoral neck were the ones that best correlated with bone volume assessed by a bone biopsy. The sensitivity of DXA for osteoporosis diagnosis was 47.0%, and the specificity was 81.2%. The positive predictive value was 50.0%, and the negative predictive value (NPV) was 80.0%. DXA parameters also correlated with klotho and sclerostin serum levels. In this population, a normal examination excluded the presence of osteoporosis, helping in identifying patients that would not benefit from therapy. Overall, densitometry in total femur and femoral neck correlated well with bone volume measured by bone biopsy.info:eu-repo/semantics/publishedVersio

    Contribution of Different Patient Information Sources to Create the Best Possible Medication History

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    Introduction: Obtaining the best possible medication history is the crucial step in medication reconciliation. Our aim was to evaluate the potential contributions of the main data sources available - patient/caregiver, hospital medical records, and shared electronic health records - to obtain an accurate 'best possible medication history'. Material and Methods: An observational cross-sectional study was conducted. Adult patients taking at least one medicine were included. Patient interview was performed upon admission and this information was reconciled with hospital medical records and shared electronic health records, assessed retrospectively. Concordance between sources was assessed. In the shared electronic health records, information was collected for four time-periods: the preceding three, six, nine and 12-months. The proportion of omitted data between time-periods was analysed. Results: A total of 148 patients were admitted, with a mean age of 54.6 +/- 16.3 years. A total of 1639 medicines were retrieved. Only 29% were collected simultaneously in the three sources of information, 40% were only obtained in shared electronic health records and only 5% were obtained exclusively from patients. The total number of medicines gathered in shared electronic health records considering the different time frames were 778 (three-months), 1397 (six-months), 1748 (nine-months), and 1933 (12-months). Discussion: The use of shared electronic health records provides data that were omitted in the other data sources available and retrieving the information at six months is the most efficient procedure to establish the basis of the best possible medication history. Conclusion: Shared electronic health records should be the preferred source of information to supplement the patient or caregiver interview in order to increase the accuracy of best possible medication history of the patient, particularly if collected within the prior six months

    The Role of Bone Volume, FGF23 and Sclerostin in Calcifications and Mortality; a Cohort Study in CKD Stage 5 Patients

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    Chronic kidney disease-mineral and bone disorder has been associated with increasing morbid-mortality. The aim of this study was to determine the prevalence and phenotype of bone disease before transplantation and to correlate FGF23 and sclerostin levels with bone histomorphometry, and study possible associations between FGF23, sclerostin, and bone histomorphometry with cardiovascular disease and mortality. We performed a cross-sectional cohort study of a sample of 84 patients submitted to renal transplant, which were prospectively followed for 12 months. Demographic, clinical, and echocardiographic data were collected, laboratory evaluation, bone biopsy, and X-ray of the pelvis and hands were performed. Patient and graft survival were recorded. We diagnosed low bone turnover in 16 patients (19.5%); high bone turnover in 22 patients (26.8%); osteomalacia in 1 patient (1.2%), and mixed renal osteodystrophy in 3 patients (3.7%). At the end of 12 months, 5 patients had graft failure (5.9%), 4 had a cardiovascular event (4.8%), and 4 died. Age was associated with low remodeling disease, whereas high BALP and phosphorus and low sclerostin with high turnover disease. Sclerostin was a risk factor for isolated low bone volume. High BALP, low phosphorus, and low FGF23 were risk factors for abnormal mineralization. FGF23 appears as an independent factor for severity of vascular calcifications and for cardiovascular events, whereas the presence of valve calcifications was associated with low volume and with turnover deviations. Sclerostin was associated a higher HR for death. Sclerostin and FGF23 seemed to provide higher cardiovascular risk, as well as low bone volume, which associated with extra-osseous calcifications.info:eu-repo/semantics/publishedVersio
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