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1.
Ear Hear ; 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38783420

RESUMEN

OBJECTIVES: The study compared the utility of two approaches for collecting real-world listening experiences to predict hearing-aid preference: a retrospective questionnaire (Speech, Spatial, and Qualities of Hearing Scale [SSQ]) and in-situ Ecological Momentary Assessment (EMA). The rationale being that each approach likely provides different and yet complementary information. In addition, it was examined how self-reported listening activity and hearing-aid data-logging can augment EMAs for individualized and contextualized hearing outcome assessments. DESIGN: Experienced hearing-aid users (N = 40) with mild-to-moderate symmetrical sensorineural hearing loss completed the SSQ questionnaire and gave repeated EMAs for two wear periods of 2-weeks each with two different hearing-aid models that differed mainly in their noise reduction technology. The EMAs were linked to a self-reported listening activity and sound environment parameters (from hearing-aid data-logging) recorded at the time of EMA completion. Wear order was randomized by hearing-aid model. Linear mixed-effects models and Random Forest models with five-fold cross-validation were used to assess the statistical associations between listening experiences and end-of-trial preferences, and to evaluate how accurately EMAs predicted preference within individuals. RESULTS: Only 6 of the 49 SSQ items significantly discriminated between responses made for the end-of-trial preferred versus nonpreferred hearing-aid model. For the EMAs, questions related to perception of the sound from the hearing aids were all significantly associated with preference, and these associations were strongest in EMAs completed in sound environments with predominantly low SNR and listening activities related to television, people talking, nonspecific listening, and music listening. Mean differences in listening experiences from SSQ and EMA correctly predicted preference in 71.8% and 72.5% of included participants, respectively. However, a prognostic classification of single EMAs into end-of-trial preference with a Random Forest model achieved a 93.8% accuracy when contextual information was included. CONCLUSIONS: SSQ and EMA predicted preference equally well when considering mean differences, however, EMAs had a high prognostic classifications accuracy due to the repeated-measures nature, which make them ideal for individualized hearing outcome investigations, especially when responses are combined with contextual information about the sound environment.

2.
Physiol Rep ; 11(24): e15899, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38129113

RESUMEN

In-depth understanding of intra- and postdialytic phosphate kinetics is important to adjust treatment regimens in hemodialysis. We aimed to modify and validate a three-compartment phosphate kinetic model to individual patient data and assess the temporal robustness. Intradialytic phosphate samples were collected from the plasma and dialysate of 12 patients during two treatments (HD1 and HD2). 2-h postdialytic plasma samples were collected in four of the patients. First, the model was fitted to HD1 samples from each patient to estimate the mass transfer coefficients. Second, the best fitted model in each patient case was validated on HD2 samples. The best model fits were determined from the coefficient of determination (R2 ) values. When fitted to intradialytic samples only, the median (interquartile range) R2 values were 0.985 (0.959-0.997) and 0.992 (0.984-0.994) for HD1 and HD2, respectively. When fitted to both intra- and postdialytic samples, the results were 0.882 (0.838-0.929) and 0.963 (0.951-0.976) for HD1 and HD2, respectively. Eight patients demonstrated a higher R2 value for HD2 than for HD1. The model seems promising to predict individual plasma phosphate in hemodialysis patients. The results also show good temporal robustness of the model. Further modifications and validation on a larger sample are needed.


Asunto(s)
Fosfatos , Diálisis Renal , Humanos , Diálisis Renal/métodos , Cinética
3.
Front Public Health ; 11: 1091706, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37905241

RESUMEN

Introduction: This study aimed to investigate the daily sound exposure of hearing aid (HA) users during the COVID-19 pandemic, with a specific focus on the impact of different governance intervention levels. Methods: Modern HA technology was employed to measure and compare the sound exposure of HA users in three distinct periods: pre-pandemic, and two 14-day periods during the pandemic, corresponding to varying levels of governance interventions. The study sample comprised a total of 386 HA users in Europe during the pandemic, with daily sound exposure data collected as part of the main dataset. Results: The results revealed that, during the pandemic, the equivalent continuous sound pressure level (SPL) experienced by HA users decreased, while the signal-to-noise ratio (SNR) increased compared to the pre-pandemic period. Notably, this impact was found to be more pronounced (p < 0.05) when individuals were subjected to stronger governance intervention levels, characterized by lower SPL and higher SNR. Discussion: This study highlights the changes in daily sound exposure experienced by HA users during the COVID-19 pandemic, particularly influenced by the extent of governance interventions that restricted social activities. These findings emphasize the importance of considering the effects of pandemic-related governance measures on the sound environments of HA users and have implications for audiological interventions and support strategies during similar crises.


Asunto(s)
COVID-19 , Audífonos , Pérdida Auditiva , Humanos , Pandemias , COVID-19/epidemiología , Sonido , Europa (Continente)/epidemiología
4.
Exp Physiol ; 108(10): 1325-1336, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37566800

RESUMEN

A coagulation component should be considered in phosphate kinetics modelling because intradialytic coagulation of the extracorporeal circuit and dialyser might reduce phosphate removal in haemodialysis. Thus, the objective of this study was to add and evaluate coagulation as an individual linear clearance reduction component to a promising three-compartment model assuming progressive intradialytic clotting. The model was modified and validated on intradialytic plasma and dialysate phosphate samples from 12 haemodialysis patients collected during two treatments (HD1 and HD2) at a Danish hospital ward. The most suitable clearance reduction in each treatment was identified by minimizing the root mean square error (RMSE). The model simulations with and without clearance reduction were compared based on RMSE and coefficient of determination (R2 ) values. Improvements were found for 17 of the 24 model simulations when clearance reduction was added to the model. The slopes of the clearance reduction were in the range of 0.011-0.632/h. Three improvements were found to be statistically significant (|observed z value| > 1.96). A very significant correlation (R2  = 0.708) between the slopes for HD1 and HD2 was found. Adding the clearance reduction component to the model seems promising in phosphate kinetics modelling and might be explained, at least in part, by intradialytic coagulation. In future studies, the model might be developed further to serve as a potentially useful tool for the quantitative detection of clotting problems in haemodialysis. NEW FINDINGS: What is the central question of this study? The aim was to add an intradialytic coagulation component to a modified version of a promising three-compartment phosphate kinetics model. The hypothesis was that circuit and dialyser clotting can be modelled by an individual linear phosphate clearance reduction component during haemodialysis treatment. What is the main finding and its importance? Improvements were found for 17 of 24 model simulations when clearance reduction was added to the model. Thus, the kinetics model seems promising and could be a useful tool for the quantitative detection of clotting problems in haemodialysis patients.


Asunto(s)
Fosfatos , Diálisis Renal , Humanos , Coagulación Sanguínea
5.
Hemodial Int ; 26(2): 191-201, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34964538

RESUMEN

INTRODUCTION: Severe infection is a major problem in hemodialysis patients. Multiplex proteomics might reveal novel insights into disease mechanisms increasing the risk of infection and might also be used as a risk prediction tool. The aims of this study were (1) to evaluate associations between 92 proteins assessed by a proximity extension assay and the development of severe infection in patients on hemodialysis and (2) to develop a risk prediction model for severe infection using prespecified clinical variables and proteomics. METHODS: Prospective, observational multicenter cohort study with 5-year follow-up. Patients receiving in-center hemodialysis in five facilities in Denmark were included. The primary composite endpoint was death caused by infection, bacteremia, and infections requiring hospitalization of at least 2 days or prolonging a hospital stay. FINDINGS: Of 331 patients included 210 patients reached the primary endpoint during follow-up. In adjusted Cox regression analyses, 14 plasma proteins were associated with severe infection. Correcting for multiple testing revealed only cathepsin-L1 and interleukin-6 significantly associated with the primary outcome. Cathepsin-L1-hazard ratio: 1.64 (95% confidence interval [CI] 1.24-2.17) and interleukin-6-hazard ratio: 1.16 (95% CI 1.05-1.29). Apparent C-statistics of the risk prediction model using clinical variables was 0.605, addition of cathepsin-L1 and interleukin-6 to the model improved discrimination slightly: C = 0.625. DISCUSSION: Proteomic profiling identified cathepsin-L1 and interleukin-6 as markers for infectious risk in hemodialysis patients. Further studies are needed to replicate the results and to examine possible causality. The developed risk prediction models need considerable improvement before implementation in clinical practice is meaningful.


Asunto(s)
Proteómica , Diálisis Renal , Biomarcadores , Estudios de Cohortes , Humanos , Estudios Prospectivos , Diálisis Renal/efectos adversos , Factores de Riesgo
6.
R Soc Open Sci ; 8(2): 201345, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33972852

RESUMEN

We investigate the short-term association between multidimensional acoustic characteristics of everyday ambient sound and continuous mean heart rate. We used in-market data from hearing aid users who logged ambient acoustics via smartphone-connected hearing aids and continuous mean heart rate in 5 min intervals from their own wearables. We find that acoustic characteristics explain approximately 4% of the fluctuation in mean heart rate throughout the day. Specifically, increases in ambient sound pressure intensity are significantly related to increases in mean heart rate, corroborating prior laboratory and short-term real-world data. In addition, increases in ambient sound quality-that is, more favourable signal to noise ratios-are associated with decreases in mean heart rate. Our findings document a previously unrecognized mixed influence of everyday sounds on cardiovascular stress, and that the relationship is more complex than is seen from an examination of sound intensity alone. Thus, our findings highlight the relevance of ambient environmental sound in models of human ecophysiology.

7.
Br J Nutr ; 126(8): 1194-1202, 2021 10 28.
Artículo en Inglés | MEDLINE | ID: mdl-33536096

RESUMEN

Long-chain n-3 PUFA (n-3 LCPUFA) are known to reduce blood pressure (BP), heart rate and vagal tone, but potential stress-mitigating effects of n-3 LCPUFA are not well investigated. We explored the effects of oily fish consumption on long-term stress and the stress response in schoolchildren. Healthy 8-9-year-old children were randomised to receive about 300 g/week of oily fish or poultry for 12 weeks (199 randomised, 197 completing). At baseline and endpoint, we measured erythrocyte n-3 LCPUFA, hair cortisol and the response to a 1-min cold pressor test (CPT) on saliva cortisol, BP and continuous electrocardiogram recordings. Post-intervention hair cortisol did not differ between the groups, but sex-specificity was indicated (Psex × group = 0·074, boys: -0·9 (95 % CI -2·9, 1·0) ng/g, girls: 0·7 (95 % CI -0·2, 1·6) ng/g). Children in the fish group tended to be less prone to terminate CPT prematurely (OR 0·20 (95 % CI 0·02, 1·04)). Mean heart beat interval during CPT was 18·2 (95 % CI 0·3, 36·6) ms longer and high frequency power increased (159 (95 % CI 29, 289) ms2) in the fish v. poultry group. The cardiac autonomic response in the 10 min following CPT was characterised by a sympathetic peak followed by a parasympathetic peak, which was most pronounced in the fish group. This exploratory study does not support a strong effect of oily fish consumption on stress but indicates that oily fish consumption may increase vagal cardiac tone during the physiological response to CPT. These results warrant further investigation.


Asunto(s)
Ácidos Grasos Omega-3 , Hidrocortisona , Alimentos Marinos , Estrés Fisiológico , Animales , Sistema Nervioso Autónomo , Niño , Femenino , Peces , Estado de Salud , Humanos , Masculino
8.
Ear Hear ; 41(5): 1057-1063, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31985536

RESUMEN

Ideally, public health policies are formulated from scientific data; however, policy-specific data are often unavailable. Big data can generate ecologically-valid, high-quality scientific evidence, and therefore has the potential to change how public health policies are formulated. Here, we discuss the use of big data for developing evidence-based hearing health policies, using data collected and analyzed with a research prototype of a data repository known as EVOTION (EVidence-based management of hearing impairments: public health pOlicy-making based on fusing big data analytics and simulaTION), to illustrate our points. Data in the repository consist of audiometric clinical data, prospective real-world data collected from hearing aids and an app, and responses to questionnaires collected for research purposes. To date, we have used the platform and a synthetic dataset to model the estimated risk of noise-induced hearing loss and have shown novel evidence of ways in which external factors influence hearing aid usage patterns. We contend that this research prototype data repository illustrates the value of using big data for policy-making by providing high-quality evidence that could be used to formulate and evaluate the impact of hearing health care policies.


Asunto(s)
Macrodatos , Formulación de Políticas , Política de Salud , Audición , Humanos , Estudios Prospectivos
9.
Am J Clin Nutr ; 110(6): 1296-1305, 2019 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-31595295

RESUMEN

BACKGROUND: Fish oil improves cardiometabolic markers in adults, but results in children are inconsistent. Few children meet the recommended fish intake and no randomized trials have investigated how fish intake per se affects children's cardiometabolic profile. OBJECTIVE: We investigated whether oily fish consumption modulated serum triacylglycerol and diastolic blood pressure (coprimary outcomes) and other cardiometabolic markers in healthy Danish children and whether effects were sex-specific. METHODS: In a randomized controlled 12-wk trial, 199 children (aged 8-9 y) received ∼300 g/wk of oily fish or poultry (control). We measured blood pressure, heart rate, and heart rate variability (HRV) via 3-h continuous electrocardiograms and collected fasting blood samples for analysis of erythrocyte EPA [20:5n-3 (ω-3)] + DHA (22:6n-3) and serum triacylglycerol, LDL and HDL cholesterol, glucose, and insulin. RESULTS: One hundred and ninety-seven children (99%) completed the trial. The fish group consumed a median (IQR) of 375 (325-426) g oily fish/wk and the poultry group consumed 400 (359-452) g poultry/wk, which resulted in 2.25 (95% CI: 1.88, 2.62) fatty acid percentage-point higher erythrocyte EPA + DHA in the fish group (P < 0.001). In the fish group, serum triacylglycerol decreased by 0.05 mmol/L (95% CI: 0.00, 0.11 mmol/L) (P = 0.04) and HDL cholesterol increased by 0.07 mmol/L (95% CI: 0.01, 0.13 mmol/L) (P = 0.02); the triacylglycerol effect showed dose-dependency with erythrocyte EPA + DHA (r = -0.15, P = 0.04), whereas HDL showed a tendency for such an association(r = 0.13, P = 0.08). Additional analyses indicated sex-specificity (Pdiet*sex < 0.10), because triacylglycerol was reduced by 0.09 mmol/L (95% CI: 0.02, 0.16 mmol/L) in boys only (girls: -0.00; 95% CI: -0.07, 0.07 mmol/L) and heart rate was reduced by 3.4 bpm (95% CI: 0.2, 6.6 bpm) in girls only (boys: 0.6; 95% CI: -2.6, 3.8 bpm). Blood pressure, HRV, and glucose homeostasis were unaffected. CONCLUSIONS: Oily fish intake improved serum triacylglycerol and HDL cholesterol in a dose-dependent manner in 8- to 9-y-old children, but had no effect on blood pressure, HRV, or glucose homeostasis. This supports recommendations for fish intake in children and underlines the importance of initiatives to increase children's intake of oily fish. This trial was registered at clinicaltrials.gov as NCT02809508.


Asunto(s)
Biomarcadores/sangre , Peces/metabolismo , Animales , Presión Sanguínea , Niño , HDL-Colesterol/sangre , LDL-Colesterol/sangre , Ácidos Docosahexaenoicos/sangre , Ácido Eicosapentaenoico/sangre , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Triglicéridos/sangre
11.
PLoS One ; 14(7): e0220502, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31344126

RESUMEN

[This corrects the article DOI: 10.1371/journal.pone.0212141.].

12.
PLoS One ; 14(2): e0212141, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30742680

RESUMEN

Orientation and position of small image segments are considered to be two fundamental low-level attributes in early visual processing, yet their encoding in complex natural stimuli is underexplored. By measuring the just-noticeable differences in noise perturbation, we investigated how orientation and position information of a large number of local elements (Gabors) were encoded separately or jointly. Importantly, the Gabors composed various classes of naturalistic stimuli that were equated by all low-level attributes and differed only in their higher-order configural complexity and familiarity. Although unable to consciously tell apart the type of perturbation, observers detected orientation and position noise significantly differently. Furthermore, when the Gabors were perturbed by both types of noise simultaneously, performance adhered to a reliability-based optimal probabilistic combination of individual attribute noises. Our results suggest that orientation and position are independently coded and probabilistically combined for naturalistic stimuli at the earliest stage of visual processing.

13.
Clin Nephrol ; 91(4): 246-253, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30614439

RESUMEN

AIMS: Iron deficiency is common in patients with chronic kidney disease (CKD). Appropriate iron substitution is critical and intravenous iron is an established therapy for these patients. The objective of this study was to assess treatment routine, -effectiveness, and safety of iron isomaltoside (Monofer®, Pharma-cosmos A/S, Holbaek, Denmark) in CKD patients in clinical practice. MATERIALS AND METHODS: This was a prospective observational study conducted in predialysis CKD patients treated with iron isomaltoside according to the product label and to routine clinical care. RESULTS: The study included 108 patients with predialysis CKD: 22 were in stage 2 - 3, 41 in stage 4, and 45 in stage 5. The mean (standard deviation) age was 67 (15) years, and 55% of patients were male. The majority of patients (65%) received one iron isomaltoside treatment. In patients with a baseline Hb < 10 g/dL, the mean dose of iron isomaltoside in the study was lower than the estimated total iron requirement (567 mg versus 921 mg). A treatment response of Hb ≥ 1 g/dL was achieved in 16/28 (57%) of patients, and the mean post-treatment Hb level was 10.5 g/dL. The probability of retreatment did not correlate with dose, but no dose administered was > 1,000 mg. There were no serious adverse drug reactions. One non-serious adverse drug reaction - injection site discoloration - was reported, and the patient had an uneventful recovery. CONCLUSION: Iron isomaltoside shows a good effectiveness and safety profile in predialysis CKD patients. However, some patients did not receive adequate iron doses to allow for optimal correction of their iron deficiency anemia.


Asunto(s)
Anemia Ferropénica/tratamiento farmacológico , Disacáridos/uso terapéutico , Compuestos Férricos/uso terapéutico , Hematínicos/uso terapéutico , Insuficiencia Renal Crónica/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Anemia Ferropénica/sangre , Anemia Ferropénica/complicaciones , Disacáridos/efectos adversos , Femenino , Compuestos Férricos/efectos adversos , Hematínicos/efectos adversos , Hemoglobinas/metabolismo , Humanos , Hierro , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Países Escandinavos y Nórdicos , Resultado del Tratamiento
14.
Kidney Med ; 1(5): 263-270, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32734206

RESUMEN

RATIONALE & OBJECTIVE: Arteriovenous fistulas are the preferred access type for hemodialysis. The buttonhole needling technique has become an alternative to stepladder or area puncture. However, an increased risk for infection has been described. The present study examined the risk for infectious complications with different needling techniques. STUDY DESIGN: Prospective multicenter observational cohort study with 5 years of follow-up. SETTING & PARTICIPANTS: In-center hemodialysis patients from 5 hemodialysis units in Denmark, dialyzed on a native arteriovenous fistula. 286 patients were included; 144 cannulated with the buttonhole technique. EXPOSURE: The buttonhole cannulation technique was compared to the stepladder or area puncture technique. OUTCOMES: Primary end points: event rates of access-related Staphylococcus aureus bacteremia and the HR for first access-related S aureus bacteremia. Secondary end points: local infections and access-related S aureus bacteremia-related metastatic infections and mortality. ANALYTICAL APPROACH: Time-to-event analysis using Cox proportional hazards regression to estimate the HR of access-related S aureus bacteremia in buttonhole cannulation compared to stepladder/area puncture. Poisson regression was used for incidence rate ratio calculations. RESULTS: S aureus caused 48 access-related bacteremias; 43 (90%) in the buttonhole group compared with 5 (10%) in the stepladder/area group. The HR for first access-related S aureus bacteremia was significantly higher for buttonhole cannulation compared to stepladder/area needling (unadjusted, 6.8 [95% CI, 2.4-19.1]; adjusted, 8.4 [95% CI, 2.9-24.2]). The incidence rate ratio for access-related S aureus bacteremia was 6.8 (95% CI, 2.9-16.1), and the incidence rate ratio of local cannulation-site infection without access-related S aureus bacteremia was 3.8 (95% CI, 1.3-15.4) for buttonhole cannulation compared to stepladder/area needling. LIMITATIONS: Nonrandomized observational design, prevalent hemodialysis patients. CONCLUSIONS: Access-related S aureus bacteremia rates were very high for buttonhole cannulation compared to stepladder/area needling, questioning the use of buttonhole cannulation in routine clinical practice. A restrictive approach to buttonhole use is recommended, with buttonhole cannulation only being used as a second alternative to area technique when stepladder cannulation is not feasible.

15.
Nutrients ; 10(9)2018 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-30227610

RESUMEN

Marine n-3 polyunsaturated fatty acids (PUFA) may improve autonomic dysfunction, as indicated by an increase in heart rate variability (HRV) and reduce the risk of sudden cardiac death. Hence, the aim of this study was to investigate the effects of marine n-3 PUFA on 24-h HRV in patients on chronic dialysis, who have a high risk of sudden cardiac death. Between June 2014 and March 2016, 112 patients on chronic dialysis from Denmark were allocated to a daily supplement of 2 g marine n-3 PUFA or control for three months in a randomized, double-blinded, controlled trial. A 48-h Holter monitoring was performed and mean 24-h HRV indices for the two days were available in 85 patients. The mean age was 62.3 years (SD: 14.3) and median dialysis vintage was 1.7 years (IQR: 0.5, 6.4). Within-group and between-group changes in outcome were evaluated by a paired and two sample t-test, respectively. Marine n-3 PUFA did not change the primary endpoint SDNN (SD of all RR-intervals) reflecting overall HRV, but other HRV indices increased and the mean RR-interval increased significantly, corresponding to a decrease in heart rate by 2.5 beats per minute (p = 0.04). In conclusion, marine n-3 PUFA did not change SDNN, but the mean heart rate was significantly reduced and changes in other HRV-indices were also observed, indicating an increase in vagal modulation that might be protective against malignant ventricular arrhythmias.


Asunto(s)
Sistema Nervioso Autónomo/fisiopatología , Muerte Súbita Cardíaca/prevención & control , Suplementos Dietéticos , Ácidos Docosahexaenoicos/administración & dosificación , Ácido Eicosapentaenoico/administración & dosificación , Frecuencia Cardíaca , Corazón/inervación , Diálisis Renal , Insuficiencia Renal Crónica/terapia , Anciano , Dinamarca , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Diálisis Renal/efectos adversos , Diálisis Renal/mortalidad , Insuficiencia Renal Crónica/diagnóstico , Insuficiencia Renal Crónica/mortalidad , Insuficiencia Renal Crónica/fisiopatología , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
16.
J Exp Psychol Hum Percept Perform ; 44(9): 1383-1398, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29708375

RESUMEN

A physiologically based nonhomogeneous Poisson counter model of visual identification is presented. The model was developed in the framework of a Theory of Visual Attention (Bundesen, 1990; Kyllingsbæk, Markussen, & Bundesen, 2012) and meant for modeling visual identification of objects that are mutually confusable and hard to see. The model assumes that the visual system's initial sensory response consists in tentative visual categorizations, which are accumulated by leaky integration of both transient and sustained components comparable with those found in spike density patterns of early sensory neurons. The sensory response (tentative categorizations) feeds independent Poisson counters, each of which accumulates tentative object categorizations of a particular type to guide overt identification performance. We tested the model's ability to predict the effect of stimulus duration on observed distributions of responses in a nonspeeded (pure accuracy) identification task with eight response alternatives. The time courses of correct and erroneous categorizations were well accounted for when the event-rates of competing Poisson counters were allowed to vary independently over time in a way that mimicked the dynamics of receptive field selectivity as found in neurophysiological studies. Furthermore, the initial sensory response yielded theoretical hazard rate functions that closely resembled empirically estimated ones. Finally, supplied with a Naka-Rushton type contrast gain control, the model provided an explanation for Bloch's law. (PsycINFO Database Record


Asunto(s)
Atención/fisiología , Toma de Decisiones/fisiología , Modelos Teóricos , Reconocimiento Visual de Modelos/fisiología , Adulto , Femenino , Humanos , Masculino , Distribución de Poisson , Adulto Joven
17.
Br J Nutr ; 120(3): 317-325, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29779501

RESUMEN

Marine n-3 PUFA may improve autonomic dysfunction by an increase in heart rate variability (HRV) and may reduce the risk of malignant ventricular arrhythmias. Only a few smaller studies have examined such effects in patients on chronic dialysis, who often have autonomic dysfunction and a high risk of sudden cardiac death, which accounts for almost 30 % of all deaths. This cross-sectional study investigated the association between the plasma phospholipid content of n-3 PUFA and 24-h HRV or ventricular arrhythmias in patients on chronic dialysis. A 48-h Holter monitoring was performed on 169 patients on in-centre dialysis (83 %), home haemodialysis (10 %) or peritoneal dialysis (7 %) obtaining data on arrhythmias (n 152) and 24-h HRV (n 135). The mean overall HRV (standard deviation of normal intervals (SDNN)) was low and 71 % had a reduced overall HRV (SDNN<100 ms) indicating autonomic dysfunction. No significant associations between plasma phospholipid content of total marine n-3 PUFA, EPA (22 : 5n-3) or DHA (22 : 6n-3) and time-domain or frequency-domain HRV were detected in crude or adjusted linear regression analysis. However, a higher plasma phospholipid content of DHA was associated with a significantly lower proportion of patients with ventricular tachycardia (higher DHA-tertile: 9 % v. lower DHA-tertile: 28 %, P=0·02). In conclusion, the content of marine n-3 PUFA in plasma phospholipids was not associated with 24-h HRV, but a higher plasma phospholipid content of DHA was associated with a lower occurrence of ventricular tachycardia suggesting an antiarrhythmic effect of marine n-3 PUFA in patients on chronic dialysis.


Asunto(s)
Arritmias Cardíacas/complicaciones , Ácidos Grasos Insaturados/sangre , Frecuencia Cardíaca/efectos de los fármacos , Fallo Renal Crónico/complicaciones , Fallo Renal Crónico/terapia , Fosfolípidos/sangre , Adulto , Anciano , Antropometría , Comorbilidad , Estudios Transversales , Dinamarca , Electrocardiografía Ambulatoria , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Diálisis Peritoneal , Análisis de Regresión , Diálisis Renal , Riesgo , Adulto Joven
18.
J Ren Nutr ; 28(2): 118-124, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29146138

RESUMEN

OBJECTIVE(S): We assessed associations between plasma levels of polyunsaturated fatty acids (PUFAs) and degree of inflammation and interstitial fibrosis in transplanted kidneys. DESIGN: The design of the study was single center cohort study. SUBJECTS: A study population of 156 patients who received a kidney transplant at Oslo University Hospital during 2010. MAIN OUTCOME MEASURE: Kidney transplant biopsies were obtained at 2 months and 1 year after transplantation. Degree of inflammation and interstitial fibrosis in the cortex of transplanted kidneys were estimated semi-quantitatively. Plasma phospholipid fatty acids levels were measured in a stable phase 2 months posttransplant. We used multivariate linear regression to assess associations between plasma levels of PUFAs and degree of inflammation and interstitial fibrosis at 2 months and 1 year postoperatively and change in degree of interstitial fibrosis during the first year after transplantation, adjusting for inflammation and fibrosis risk factors. RESULTS: Higher plasma marine n-3 PUFA levels were associated with less development of interstitial fibrosis in the kidney transplant (unstandardized ß-coefficient -1.12, standardized ß-coefficient -0.18, P = .03) during the first year after transplantation. Plasma levels of alpha linoleic acid, linoleic acid, and arachidonic acid were not associated with development of interstitial fibrosis. No associations were found between plasma levels of PUFAs and inflammation inside fibrotic areas or outside fibrotic areas in the kidney transplant at neither 2 months nor 1 year postoperatively. Linolenic acid levels in plasma were positively associated with change in renal function during the first year after transplantation. CONCLUSION: The inverse association between plasma marine n-3 PUFA levels and development of interstitial fibrosis during the first year after kidney transplantation suggests that marine fatty acid consumption might halt progression of fibrosis.


Asunto(s)
Ácidos Grasos Insaturados/sangre , Trasplante de Riñón/efectos adversos , Riñón/patología , Adulto , Anciano , Biopsia , Estudios de Cohortes , Ácidos Grasos Omega-3/sangre , Femenino , Fibrosis , Tasa de Filtración Glomerular/fisiología , Humanos , Inflamación/sangre , Riñón/fisiopatología , Ácidos Linolénicos/sangre , Masculino , Persona de Mediana Edad , Noruega
19.
Nutr Res ; 38: 71-78, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28291551

RESUMEN

Marine long-chained n-3 polyunsaturated fatty acids (PUFA) are recognized for their cardio-protective effects, including potential lowering of blood pressure. We hypothesized that higher habitual fish intake and n-3 PUFA plasma levels were associated with lower blood pressure and being less likely to receive antihypertensive medication after one-year follow-up. In this prospective study of 115 patients, we assessed 24 h ambulatory and central blood pressure, plasma phospholipid fatty acid composition using gas chromatography and participants completed a food frequency questionnaire, including fish-eating habits. All measurements were repeated at one-year follow-up. At baseline, patients consuming fish ≥2 times per month for dinner had significantly higher plasma levels of total marine n-3 PUFA, docosahexaenoic acid and eicosapentaenoic acid as well as significantly lower central blood pressure and a trend towards lower peripheral blood pressure. At follow-up, 21 patients (18%) without antihypertensive medication had significantly higher plasma levels of n-3 PUFA, docosahexaenoic acid and eicosapentaenoic acid as well as a higher, but still acceptable 24 h ambulatory blood pressure (137/85 mmHg) compared to subjects receiving antihypertensive medication. The untreated group was more prone to take fish oil capsules and increased their plasma levels of n-3 PUFA compared to baseline. In patients with newly diagnosed, untreated hypertension, regular fish consumption was accompanied by lower blood pressure. After one year, patients without antihypertensive medication were characterized by a significant increase and higher plasma levels of n-3 PUFA. This supports a blood pressure-lowering effect and suggests an increase in marine n-3 PUFA intake as part of non-pharmacological treatment of hypertension.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Dieta , Ácidos Grasos Omega-3/uso terapéutico , Conducta Alimentaria , Hipertensión/tratamiento farmacológico , Adulto , Anciano , Animales , Antihipertensivos/farmacología , Antihipertensivos/uso terapéutico , Ácidos Docosahexaenoicos/farmacología , Ácidos Docosahexaenoicos/uso terapéutico , Ácido Eicosapentaenoico/farmacología , Ácido Eicosapentaenoico/uso terapéutico , Ácidos Grasos Omega-3/farmacología , Ácidos Grasos Insaturados/farmacología , Femenino , Aceites de Pescado/farmacología , Peces , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Fosfolípidos/metabolismo , Estudios Prospectivos
20.
J Ren Nutr ; 27(3): 161-168, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-27838193

RESUMEN

OBJECTIVE: Marine n-3 polyunsaturated fatty acids (PUFAs) exert potential anti-inflammatory effects and might improve long-term outcomes after renal transplantation. We assessed associations between plasma phospholipid levels of marine n-3 PUFAs and plasma inflammatory biomarkers 10 weeks after renal transplantation. DESIGN: Cross-sectional single-center study. SUBJECTS: A study population of 861 renal transplant recipients transplanted at Oslo University Hospital between 2007 and 2011. METHODS AND MAIN OUTCOME MEASURE: Plasma phospholipid fatty acids were determined by gas chromatography. Marine n-3 PUFA levels were defined as the sum of eicosapentaenoic acid, docosahexaenoic acid, and docosapentaenoic acid levels in weight percentage of total plasma phospholipid fatty acids. Plasma inflammatory biomarkers were measured by enzyme immunoassays. We used multivariable linear regression analysis to assess associations between levels of marine n-3 PUFAs and inflammatory biomarkers in plasma. RESULTS: Plasma marine n-3 PUFA levels were inversely associated with plasma levels of proinflammatory biomarkers soluble tumor necrosis factor receptor 1 (standardized regression coefficient -0.11, P < .001) and interleukin-6 (standardized regression coefficient -0.09, P = .01). In contrast, there was no association between plasma levels of marine n-3 PUFAs and the anti-inflammatory mediator interleukin-10. CONCLUSIONS: In this renal transplant cohort, inverse associations between plasma levels of marine n-3 PUFAs and markers of inflammation were demonstrated.


Asunto(s)
Ácidos Grasos Omega-3/sangre , Interleucina-6/sangre , Trasplante de Riñón , Receptores Tipo I de Factores de Necrosis Tumoral/sangre , Adolescente , Adulto , Biomarcadores/sangre , Estudios Transversales , Ácido Eicosapentaenoico/sangre , Ácidos Grasos Insaturados/sangre , Femenino , Humanos , Interleucina-10/sangre , Modelos Lineales , Masculino , Persona de Mediana Edad , Análisis Multivariante , Fosfolípidos/sangre , Receptores de Trasplantes , Adulto Joven
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