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Biological Psychology Jul 2022This paper reviews the many functions of the vagus nerve, to understand how they interact in daily life and what might be accomplished by therapeutical electrical... (Review)
Review
This paper reviews the many functions of the vagus nerve, to understand how they interact in daily life and what might be accomplished by therapeutical electrical stimulation. A short historical introduction on the discovery and name-giving of the cranial nerves numbers 9-12 is followed by an overview of the functions that are under lower brain stem control: heart (rate, contractility), intestine (swallowing, peristalsis and glands secretions, feeling of satiety), lungs (bronchoconstriction, lung-irritant and stretch receptor signaling), blood pressure (by vascular wall stress sensing) and blood gases by specialized receptors. Key in the review is the physiology behind beat-by-beat heart rate variations, how everyday life is reflected in its variability, from exciting moments to quiet sleep, with the 'common faint' or vasovagal collapse as extreme example. Next, the recently proposed role of the vagus nerve in limiting inflammation is discussed. This has led to adoption of an earlier developed technique for epilepsy treatment, i.e., electrical stimulation of one vagus nerve bundle in the neck, but now for immune diseases like rheumatoid arthritis and the scope is even widening to depression and cluster headache. However, the problem in application of whole vagus nerve stimulation is the lack of specificity: there is no way to titrate the stimulation to an observable effect variable. All nerves in the bundle, incoming and outgoing, can be 'hit', leading to side-effects which limit the intended application.
Topics: Blood Pressure; Electric Stimulation; Heart Rate; Humans; Vagus Nerve; Vagus Nerve Stimulation
PubMed: 35688294
DOI: 10.1016/j.biopsycho.2022.108378 -
Bulletin of Emergency and Trauma Apr 2022To review the research dimensions of trauma registry data on health policy making. (Review)
Review
OBJECTIVE
To review the research dimensions of trauma registry data on health policy making.
METHODS
PubMed and EMBASE were searched until July 2020. Keywords were used on the search process included Trauma, Injury, Registry and Research, which were searched by using appropriate search strategies. The included articles had to: 1. be extracted from data related to trauma registries; 2- be written in English; 3- define a time period and a patient population; 4- preferably have more details and policy recommendations; and 5- preferably have a discussion on how to improve diagnosis and treatment. The results obtained from the included studies were qualitatively analyzed using thematic synthesis and comparative tables.
RESULTS
In the primary round of search, 19559 studies were retrieved. According to PRISMA statement and also performing quality appraisal process, 30 studies were included in the final phase of analysis. In the final papers' synthesis, 14 main research domains were extracted and classified in terms of the policy implication and research priority. The domains with the highest frequency were "The relationship between trauma registry data and hospital care protocols for trauma patients" and "The causes of Disability Adjusted Life Years (DALYs) due to trauma".
CONCLUSION
Using trauma registry data as a tool for policy-making could be helpful in several ways, namely increasing the quality of patient care, preventing injuries and decreasing their number, figuring out the details of socioeconomic status effects, and improving the quality of researches in practical ways. Also, follow-up of patients after trauma surgery as one of the positive effects of the trauma registry can be the focus of attention of policy-making bodies.
PubMed: 35434165
DOI: 10.30476/BEAT.2021.91755.1286 -
Experimental Brain Research Sep 2021Nowadays a popular technique to improve mood and cognition is auditory beat stimulation (ABS), which is thought to induce a frequency-following response of brainwaves....
Nowadays a popular technique to improve mood and cognition is auditory beat stimulation (ABS), which is thought to induce a frequency-following response of brainwaves. The main types of ABS are monaural beats (MB) and binaural beats (BB). BB involves the presentation of a specific frequency to one ear and another frequency to the other ear which may induce neural entrainment. A difference between the frequencies of 40 Hz is assumed to improve cognition. The present study examined the effect of 40 Hz binaural beats (BB) and monaural beats (MB) on attention and electroencephalography (EEG). A total of 25 first-year psychology students (11 males, 14 females) performed a Flanker task while EEG was recorded during the 5 min-presentation of pink noise (PN), MB and BB. With respect to attention, as measured by the Flanker task, the number of false responses in the BB condition was smaller than that in the PN condition while the number of false responses in the MB condition was larger as compared to the PN condition. As there was no association of BB with a consistent increase in absolute 40 or 45 Hz power compared to PN or MB, EEG recordings could not confirm the hypothesized neural entrainment in the brain. Overall, the current findings show that listening to 40 Hz BB improves attention but do not show the occurrence of neural entrainment. Future research is recommended to include a larger sample, to use a broader cognitive test battery and to present auditory beats with a longer duration.
Topics: Acoustic Stimulation; Attention; Auditory Perception; Brain Waves; Electroencephalography; Female; Humans; Male
PubMed: 34245340
DOI: 10.1007/s00221-021-06155-z -
Nutrients Sep 2022Easier recognition and enhanced visibility of healthy options supposedly increase healthy choices, but real-world evidence remains scarce. Addressing this knowledge gap,...
Easier recognition and enhanced visibility of healthy options supposedly increase healthy choices, but real-world evidence remains scarce. Addressing this knowledge gap, we promoted nutritionally favourable foods in a workplace cafeteria with three choice-architectural strategies-priming posters, point-of-choice nutrition labels, and improved product placement-and assessed their effects on visual attention, food choices, and food consumption. Additionally, we developed a method for analysing real-world eye-tracking data. The study followed a pretest-posttest design whereby control and intervention condition lasted five days each. We monitored visual attention (i.e., total number and duration of fixations) and food choices with eye tracking, interviewed customers about perceived influences on food choices, and measured cafeteria-level food consumption (g). Individual-level data represents 22 control and 19 intervention participants recruited at the cafeteria entrance. Cafeteria-level data represents food consumption during the trial (556/589 meals sold). Results indicated that the posters and labels captured participants' visual attention (~13% of fixations on defined areas of interest before food choices), but the intervention had insignificant effects on visual attention to foods, on food choices, and on food consumption. Interviews revealed 17 perceived influences on food choices, the most common being sensory appeal, healthiness, and familiarity. To conclude, the intervention appeared capable of attracting visual attention, yet ineffective in increasing healthier eating. The developed method enabled a rigorous analysis of visual attention and food choices in a natural choice setting. We discuss ways to boost the impact of the intervention on behaviour, considering target groups' motives. The work contributes with a unique, mixed-methods approach and a real-world setting that enabled a multi-dimensional effects evaluation with high external validity.
Topics: Choice Behavior; Food Preferences; Food Services; Humans; Meals; Workplace
PubMed: 36145107
DOI: 10.3390/nu14183731 -
Folia Medica Cracoviensia Sep 2022Autonomic dysfunction, impaired baroreflex sensitivity (BRS), and deranged circulatory homeostasis have been observed in chronic hyperglycemia and found to be associated...
BACKGROUND
Autonomic dysfunction, impaired baroreflex sensitivity (BRS), and deranged circulatory homeostasis have been observed in chronic hyperglycemia and found to be associated with increased cardiovascular morbidity and mortality. However, the acute effects of hyperglycemia in healthy subjects have been rarely studied. The present study explores the effect of acute hyperglycemia on conventional and unconventional parameters of BRS in healthy young adults.
METHODS
For the estimation of BRS beat-to-beat blood pressure (BP) and electrocardiogram were recorded in forty-two young, healthy subjects during fasting and at 1hr of the oral glucose load. Analysis of BRS was carried out by sequence and spectral method. Number of UP-, DOWN- and ALL-sequences between ramps of BP and RR-interval were calculated as an unconventional measure of BRS along with the other conventional parameters.
RESULTS
We observed significant alteration of unconventional parameters of autonomic functions [the number of sequences of UP- (p = 0.0039) and ALL-sequences (p = 0.0233) of systolic BP and RR interval; and, UP- (p = 0.0380), DOWN- (p = 0.0417) and ALL-sequences (p = 0.0313) of mean BP and RR- interval] during acute hyperglycemia as compared to the fasting state. However, no significant changes were observed in any of the conventional parameters of BRS during acute hyperglycemia as compared to the fasting state.
CONCLUSIONS
Present study concludes that the unconventional parameters of BRS - the number of sequences between the ramp of BP and RR-interval - change significantly during acute hyperglycemia. However, the conventional parameters do not show significant changes during acute hyperglycemia. We may hypothesize that the relatively constant BRS is maintained at the expense of increased oscillations in the ramp of BP and RR-interval.
Topics: Young Adult; Humans; Baroreflex; Heart Rate; Blood Pressure; Hyperglycemia; Electrocardiography; Acute Disease
PubMed: 36309836
DOI: 10.24425/fmc.2022.142374 -
International Journal of Molecular... May 2023Adipose tissue (AT) can be classified into two different types: (i) white adipose tissue (WAT), which represents the largest amount of total AT, and has the main... (Review)
Review
Adipose tissue (AT) can be classified into two different types: (i) white adipose tissue (WAT), which represents the largest amount of total AT, and has the main function of storing fatty acids for energy needs and (ii) brown adipose tissue (BAT), rich in mitochondria and specialized in thermogenesis. Many exogenous stimuli, e.g., cold, exercise or pharmacological/nutraceutical tools, promote the phenotypic change of WAT to a beige phenotype (BeAT), with intermediate characteristics between BAT and WAT; this process is called "browning". The modulation of AT differentiation towards WAT or BAT, and the phenotypic switch to BeAT, seem to be crucial steps to limit weight gain. Polyphenols are emerging as compounds able to induce browning and thermogenesis processes, potentially via activation of sirtuins. SIRT1 (the most investigated sirtuin) activates a factor involved in mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α), which, through peroxisome proliferator-activated receptor γ (PPAR-γ) modulation, induces typical genes of BAT and inhibits genes of WAT during the transdifferentiation process in white adipocytes. This review article aims to summarize the current evidence, from pre-clinical studies to clinical trials, on the ability of polyphenols to promote the browning process, with a specific focus on the potential role of sirtuins in the pharmacological/nutraceutical effects of natural compounds.
Topics: Humans; Sirtuins; Polyphenols; PPAR gamma; Obesity; Adipose Tissue, White; Adipose Tissue, Brown; Thermogenesis
PubMed: 37298226
DOI: 10.3390/ijms24119276 -
Nature Communications Oct 2021The axonemal central pair (CP) are non-centrosomal microtubules critical for planar ciliary beat. How they form, however, is poorly understood. Here, we show that...
The axonemal central pair (CP) are non-centrosomal microtubules critical for planar ciliary beat. How they form, however, is poorly understood. Here, we show that mammalian CP formation requires Wdr47, Camsaps, and microtubule-severing activity of Katanin. Katanin severs peripheral microtubules to produce central microtubule seeds in nascent cilia. Camsaps stabilize minus ends of the seeds to facilitate microtubule outgrowth, whereas Wdr47 concentrates Camsaps into the axonemal central lumen to properly position central microtubules. Wdr47 deficiency in mouse multicilia results in complete loss of CP, rotatory beat, and primary ciliary dyskinesia. Overexpression of Camsaps or their microtubule-binding regions induces central microtubules in Wdr47 ependymal cells but at the expense of low efficiency, abnormal numbers, and wrong location. Katanin levels and activity also impact the central microtubule number. We propose that Wdr47, Camsaps, and Katanin function together for the generation of non-centrosomal microtubule arrays in polarized subcellular compartments.
Topics: Animals; Axoneme; Cilia; Ciliary Motility Disorders; Gene Expression; Katanin; Mice; Microtubule-Associated Proteins; Microtubules; Nerve Tissue Proteins
PubMed: 34608154
DOI: 10.1038/s41467-021-26058-5 -
The European Physical Journal. E, Soft... Apr 2021We present a multi-scale modeling and simulation framework for low-Reynolds number hydrodynamics of shape-changing immersed objects, e.g., biological microswimmers and...
We present a multi-scale modeling and simulation framework for low-Reynolds number hydrodynamics of shape-changing immersed objects, e.g., biological microswimmers and active surfaces. The key idea is to consider principal shape changes as generalized coordinates and define conjugate generalized hydrodynamic friction forces. Conveniently, the corresponding generalized friction coefficients can be pre-computed and subsequently reused to solve dynamic equations of motion fast. This framework extends Lagrangian mechanics of dissipative systems to active surfaces and active microswimmers, whose shape dynamics is driven by internal forces. As an application case, we predict in-phase and anti-phase synchronization in pairs of cilia for an experimentally measured cilia beat pattern.
PubMed: 33834308
DOI: 10.1140/epje/s10189-021-00016-x -
Proceedings of the National Academy of... Jan 2021Unicellular flagellated protists are a key element in aquatic microbial food webs. They all use flagella to swim and to generate feeding currents to encounter prey and...
Unicellular flagellated protists are a key element in aquatic microbial food webs. They all use flagella to swim and to generate feeding currents to encounter prey and enhance nutrient uptake. At the same time, the beating flagella create flow disturbances that attract flow-sensing predators. Protists have highly diverse flagellar arrangements in terms of number of flagella and their position, beat pattern, and kinematics, but it is unclear how the various arrangements optimize the fundamental trade-off between resource acquisition and predation risk. Here we describe the near-cell flow fields produced by 15 species and demonstrate consistent relationships between flagellar arrangement and swimming speed and between flagellar arrangement and flow architecture, and a trade-off between resource acquisition and predation risk. The flow fields fall in categories that are qualitatively described by simple point force models that include the drag force of the moving cell body and the propulsive forces of the flagella. The trade-off between resource acquisition and predation risk varies characteristically between flow architectures: Flagellates with multiple flagella have higher predation risk relative to their clearance rate compared to species with only one active flagellum, with the exception of the highly successful dinoflagellates that have simultaneously achieved high clearance rates and stealth behavior due to a unique flagellar arrangement. Microbial communities are shaped by trade-offs and environmental constraints, and a mechanistic explanation of foraging trade-offs is a vital part of understanding the eukaryotic communities that form the basis of pelagic food webs.
Topics: Animals; Dinoflagellida; Feeding Behavior; Flagella; Food Chain; Models, Biological; Movement; Plankton; Predatory Behavior
PubMed: 33431666
DOI: 10.1073/pnas.2009930118 -
Heart (British Cardiac Society) Jun 2021To improve the echocardiographic assessment of heart failure in patients with atrial fibrillation (AF) by comparing conventional averaging of consecutive beats with an...
OBJECTIVE
To improve the echocardiographic assessment of heart failure in patients with atrial fibrillation (AF) by comparing conventional averaging of consecutive beats with an index-beat approach, whereby measurements are taken after two cycles with similar R-R interval.
METHODS
Transthoracic echocardiography was performed using a standardised and blinded protocol in patients enrolled in the RATE-AF (RAte control Therapy Evaluation in permanent Atrial Fibrillation) randomised trial. We compared reproducibility of the index-beat and conventional consecutive-beat methods to calculate left ventricular ejection fraction (LVEF), global longitudinal strain (GLS) and E/e' (mitral E wave max/average diastolic tissue Doppler velocity), and assessed intraoperator/interoperator variability, time efficiency and validity against natriuretic peptides.
RESULTS
160 patients were included, 46% of whom were women, with a median age of 75 years (IQR 69-82) and a median heart rate of 100 beats per minute (IQR 86-112). The index-beat had the lowest within-beat coefficient of variation for LVEF (32%, vs 51% for 5 consecutive beats and 53% for 10 consecutive beats), GLS (26%, vs 43% and 42%) and E/e' (25%, vs 41% and 41%). Intraoperator (n=50) and interoperator (n=18) reproducibility were both superior for index-beats and this method was quicker to perform (p<0.001): 35.4 s to measure E/e' (95% CI 33.1 to 37.8) compared with 44.7 s for 5-beat (95% CI 41.8 to 47.5) and 98.1 s for 10-beat (95% CI 91.7 to 104.4) analyses. Using a single index-beat did not compromise the association of LVEF, GLS or E/e' with natriuretic peptide levels.
CONCLUSIONS
Compared with averaging of multiple beats in patients with AF, the index-beat approach improves reproducibility and saves time without a negative impact on validity, potentially improving the diagnosis and classification of heart failure in patients with AF.
Topics: Aged; Aged, 80 and over; Atrial Fibrillation; Biomarkers; Diastole; Echocardiography, Doppler, Pulsed; Female; Heart Failure; Humans; Male; Natriuretic Peptide, Brain; Peptide Fragments; Reproducibility of Results; Stroke Volume; Systole; Ventricular Function, Left
PubMed: 33692093
DOI: 10.1136/heartjnl-2020-318557