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  1. Article ; Online: Is Increased Caloric Intake a Feature of NAFLD Regardless of the Presence of Obesity.

    Szilagyi, Andrew

    Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association

    2023  

    Language English
    Publishing date 2023-09-13
    Publishing country United States
    Document type Letter
    ZDB-ID 2119789-1
    ISSN 1542-7714 ; 1542-3565
    ISSN (online) 1542-7714
    ISSN 1542-3565
    DOI 10.1016/j.cgh.2023.08.032
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Stochastic parabolic growth promotes coexistence and a relaxed error threshold in RNA-like replicator populations.

    Paczkó, Mátyás / Szathmáry, Eörs / Szilágyi, András

    eLife

    2024  Volume 13

    Abstract: The RNA world hypothesis proposes that during the early evolution of life, primordial genomes of the first self-propagating evolutionary units existed in the form of RNA-like polymers. Autonomous, non-enzymatic, and sustained replication of such ... ...

    Abstract The RNA world hypothesis proposes that during the early evolution of life, primordial genomes of the first self-propagating evolutionary units existed in the form of RNA-like polymers. Autonomous, non-enzymatic, and sustained replication of such information carriers presents a problem, because product formation and hybridization between template and copy strands reduces replication speed. Kinetics of growth is then parabolic with the benefit of entailing competitive coexistence, thereby maintaining diversity. Here, we test the information-maintaining ability of parabolic growth in stochastic multispecies population models under the constraints of constant total population size and chemostat conditions. We find that large population sizes and small differences in the replication rates favor the stable coexistence of the vast majority of replicator species ('genes'), while the error threshold problem is alleviated relative to exponential amplification. In addition, sequence properties (GC content) and the strength of resource competition mediated by the rate of resource inflow determine the number of coexisting variants, suggesting that fluctuations in building block availability favored repeated cycles of exploration and exploitation. Stochastic parabolic growth could thus have played a pivotal role in preserving viable sequences generated by random abiotic synthesis and providing diverse genetic raw material to the early evolution of functional ribozymes.
    MeSH term(s) RNA/genetics ; RNA/metabolism ; Stochastic Processes ; Evolution, Molecular
    Chemical Substances RNA (63231-63-0)
    Language English
    Publishing date 2024-04-26
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2687154-3
    ISSN 2050-084X ; 2050-084X
    ISSN (online) 2050-084X
    ISSN 2050-084X
    DOI 10.7554/eLife.93208
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Machine Learning on Prediction of Relative Physical Activity Intensity Using Medical Radar Sensor and 3D Accelerometer.

    Biró, Attila / Szilágyi, Sándor Miklós / Szilágyi, László / Martín-Martín, Jaime / Cuesta-Vargas, Antonio Ignacio

    Sensors (Basel, Switzerland)

    2023  Volume 23, Issue 7

    Abstract: Background: One of the most critical topics in sports safety today is the reduction in injury risks through controlled fatigue using non-invasive athlete monitoring. Due to the risk of injuries, it is prohibited to use accelerometer-based smart trackers, ...

    Abstract Background: One of the most critical topics in sports safety today is the reduction in injury risks through controlled fatigue using non-invasive athlete monitoring. Due to the risk of injuries, it is prohibited to use accelerometer-based smart trackers, activity measurement bracelets, and smart watches for recording health parameters during performance sports activities. This study analyzes the synergy feasibility of medical radar sensors and tri-axial acceleration sensor data to predict physical activity key performance indexes in performance sports by using machine learning (ML). The novelty of this method is that it uses a 24 GHz Doppler radar sensor to detect vital signs such as the heartbeat and breathing without touching the person and to predict the intensity of physical activity, combined with the acceleration data from 3D accelerometers.
    Methods: This study is based on the data collected from professional athletes and freely available datasets created for research purposes. A combination of sensor data management was used: a medical radar sensor with no-contact remote sensing to measure the heart rate (HR) and 3D acceleration to measure the velocity of the activity. Various advanced ML methods and models were employed on the top of sensors to analyze the vital parameters and predict the health activity key performance indexes. three-axial acceleration, heart rate data, age, as well as activity level variances.
    Results: The ML models recognized the physical activity intensity and estimated the energy expenditure on a realistic level. Leave-one-out (LOO) cross-validation (CV), as well as out-of-sample testing (OST) methods, have been used to evaluate the level of accuracy in activity intensity prediction. The energy expenditure prediction with three-axial accelerometer sensors by using linear regression provided 97-99% accuracy on selected sports (cycling, running, and soccer). The ML-based RPE results using medical radar sensors on a time-series heart rate (HR) dataset varied between 90 and 96% accuracy. The expected level of accuracy was examined with different models. The average accuracy for all the models (RPE and METs) and setups was higher than 90%.
    Conclusions: The ML models that classify the rating of the perceived exertion and the metabolic equivalent of tasks perform consistently.
    MeSH term(s) Humans ; Radar ; Exercise/physiology ; Machine Learning ; Running ; Accelerometry/methods
    Language English
    Publishing date 2023-03-30
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s23073595
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: AI-Assisted Fatigue and Stamina Control for Performance Sports on IMU-Generated Multivariate Times Series Datasets.

    Biró, Attila / Cuesta-Vargas, Antonio Ignacio / Szilágyi, László

    Sensors (Basel, Switzerland)

    2023  Volume 24, Issue 1

    Abstract: Background: Optimal sports performance requires a balance between intensive training and adequate rest. IMUs provide objective, quantifiable data to analyze performance dynamics, despite the challenges in quantifying athlete training loads. The ability ... ...

    Abstract Background: Optimal sports performance requires a balance between intensive training and adequate rest. IMUs provide objective, quantifiable data to analyze performance dynamics, despite the challenges in quantifying athlete training loads. The ability of AI to analyze complex datasets brings innovation to the monitoring and optimization of athlete training cycles. Traditional techniques rely on subjective assessments to prevent overtraining, which can lead to injury and underperformance. IMUs provide objective, quantitative data on athletes' physical status during action. AI and machine learning can turn these data into useful insights, enabling data-driven athlete performance management. With IMU-generated multivariate time series data, this paper uses AI to construct a robust model for predicting fatigue and stamina.
    Materials and methods: IMUs linked to 19 athletes recorded triaxial acceleration, angular velocity, and magnetic orientation throughout repeated sessions. Standardized training included steady-pace runs and fatigue-inducing techniques. The raw time series data were used to train a supervised ML model based on frequency and time-domain characteristics. The performances of Random Forest, Gradient Boosting Machines, and LSTM networks were compared. A feedback loop adjusted the model in real time based on prediction error and bias estimation.
    Results: The AI model demonstrated high predictive accuracy for fatigue, showing significant correlations between predicted fatigue levels and observed declines in performance. Stamina predictions enabled individualized training adjustments that were in sync with athletes' physiological thresholds. Bias correction mechanisms proved effective in minimizing systematic prediction errors. Moreover, real-time adaptations of the model led to enhanced training periodization strategies, reducing the risk of overtraining and improving overall athletic performance.
    Conclusions: In sports performance analytics, the AI-assisted model using IMU multivariate time series data is effective. Training can be tailored and constantly altered because the model accurately predicts fatigue and stamina. AI models can effectively forecast the beginning of weariness before any physical symptoms appear. This allows for timely interventions to prevent overtraining and potential accidents. The model shows an exceptional ability to customize training programs according to the physiological reactions of each athlete and enhance the overall training effectiveness. In addition, the study demonstrated the model's efficacy in real-time monitoring performance, improving the decision-making abilities of both coaches and athletes. The approach enables ongoing and thorough data analysis, supporting strategic planning for training and competition, resulting in optimized performance outcomes. These findings highlight the revolutionary capability of AI in sports science, offering a future where data-driven methods greatly enhance athlete training and performance management.
    MeSH term(s) Humans ; Time Factors ; Athletic Performance ; Acceleration ; Fatigue ; Machine Learning
    Language English
    Publishing date 2023-12-26
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2052857-7
    ISSN 1424-8220 ; 1424-8220
    ISSN (online) 1424-8220
    ISSN 1424-8220
    DOI 10.3390/s24010132
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: Assessing the Spontaneous Spread of Climate-Adapted Woody Plants in an Extensively Maintained Collection Garden.

    Szabó, Krisztina / Gergely, Attila / Tóth, Barnabás / Szilágyi, Kinga

    Plants (Basel, Switzerland)

    2023  Volume 12, Issue 10

    Abstract: Climate change may strongly modify the habitat conditions for many woody plant species. Some species could disappear from their natural habitats and become endangered, while others could adapt well to the changed environmental conditions and continue to ... ...

    Abstract Climate change may strongly modify the habitat conditions for many woody plant species. Some species could disappear from their natural habitats and become endangered, while others could adapt well to the changed environmental conditions and continue to survive successfully or even proliferate more easily. A similar process can occur within the artificial urban environment as the hitherto popularly planted urban trees may suffer from the extremities of the urban climate. However, among the planted taxa, there are species that spread spontaneously and appear as weeds in extensively managed gardens. In our study, we evaluated the native and non-native species involved in spontaneous spreading in the institutional garden of Buda Arboretum (Budapest) during the COVID-19 period in 2020-2021 when entry was prohibited, and maintenance went on in a restricted, minimal level. We investigated the correlation between spontaneously settling and planted individuals, and then performed multivariate analyses for native and non-native spreading plants for spatial and quantitative data. During our studies, we observed the spontaneous spreading of 114 woody species, of which 38 are native and 76 are non-native. Taking the total number of individuals into account, we found that, in addition to the 2653 woody species planted, a further 7087 spontaneously emerged weeds developed, which creates an additional task in the maintenance.
    Language English
    Publishing date 2023-05-15
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2704341-1
    ISSN 2223-7747
    ISSN 2223-7747
    DOI 10.3390/plants12101989
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: A Kinetic Transition Network Model Reveals the Diversity of Protein Dimer Formation Mechanisms.

    Györffy, Dániel / Závodszky, Péter / Szilágyi, András

    Biomolecules

    2023  Volume 13, Issue 12

    Abstract: Protein homodimers have been classified as three-state or two-state dimers depending on whether a folded monomer forms before association, but the details of the folding-binding mechanisms are poorly understood. Kinetic transition networks of ... ...

    Abstract Protein homodimers have been classified as three-state or two-state dimers depending on whether a folded monomer forms before association, but the details of the folding-binding mechanisms are poorly understood. Kinetic transition networks of conformational states have provided insight into the folding mechanisms of monomeric proteins, but extending such a network to two protein chains is challenging as all the relative positions and orientations of the chains need to be included, greatly increasing the number of degrees of freedom. Here, we present a simplification of the problem by grouping all states of the two chains into two layers: a dissociated and an associated layer. We combined our two-layer approach with the Wako-Saito-Muñoz-Eaton method and used Transition Path Theory to investigate the dimer formation kinetics of eight homodimers. The analysis reveals a remarkable diversity of dimer formation mechanisms. Induced folding, conformational selection, and rigid docking are often simultaneously at work, and their contribution depends on the protein concentration. Pre-folded structural elements are always present at the moment of association, and asymmetric binding mechanisms are common. Our two-layer network approach can be combined with various methods that generate discrete states, yielding new insights into the kinetics and pathways of flexible binding processes.
    MeSH term(s) Protein Folding ; Proteins/chemistry ; Molecular Conformation ; Protein Biosynthesis ; Kinetics ; Thermodynamics
    Chemical Substances Proteins
    Language English
    Publishing date 2023-11-26
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2701262-1
    ISSN 2218-273X ; 2218-273X
    ISSN (online) 2218-273X
    ISSN 2218-273X
    DOI 10.3390/biom13121708
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Directional selection coupled with kin selection favors the establishment of senescence.

    Szilágyi, András / Czárán, Tamás / Santos, Mauro / Szathmáry, Eörs

    BMC biology

    2023  Volume 21, Issue 1, Page(s) 230

    Abstract: Background: Conventional wisdom in evolutionary theory considers aging as a non-selected byproduct of natural selection. Based on this, conviction aging was regarded as an inevitable phenomenon. It was also thought that in the wild organisms tend to die ...

    Abstract Background: Conventional wisdom in evolutionary theory considers aging as a non-selected byproduct of natural selection. Based on this, conviction aging was regarded as an inevitable phenomenon. It was also thought that in the wild organisms tend to die from diseases, predation and other accidents before they could reach the time when senescence takes its course. Evidence has accumulated, however, that aging is not inevitable and there are organisms that show negative aging even. Furthermore, old age does play a role in the deaths of many different organisms in the wild also. The hypothesis of programmed aging posits that a limited lifespan can evolve as an adaptation (i.e., positively selected for) in its own right, partly because it can enhance evolvability by eliminating "outdated" genotypes. A major shortcoming of this idea is that non-aging sexual individuals that fail to pay the demographic cost of aging would be able to steal good genes by recombination from aging ones.
    Results: Here, we show by a spatially explicit, individual-based simulation model that aging can positively be selected for if a sufficient degree of kin selection complements directional selection. Under such conditions, senescence enhances evolvability because the rate of aging and the rate of recombination play complementary roles. The selected aging rate is highest at zero recombination (clonal reproduction). In our model, increasing extrinsic mortality favors evolved aging by making up free space, thereby decreasing competition and increasing drift, even when selection is stabilizing and the level of aging is set by mutation-selection balance. Importantly, higher extrinsic mortality is not a substitute for evolved aging under directional selection either. Reduction of relatedness decreases the evolved level of aging; chance relatedness favors non-aging genotypes. The applicability of our results depends on empirical values of directional and kin selection in the wild.
    Conclusions: We found that aging can positively be selected for in a spatially explicit population model when sufficiently strong directional and kin selection prevail, even if reproduction is sexual. The view that there is a conceptual link between giving up clonal reproduction and evolving an aging genotype is supported by computational results.
    MeSH term(s) Humans ; Aging/genetics ; Longevity ; Mutation ; Reproduction ; Biological Evolution ; Selection, Genetic
    Language English
    Publishing date 2023-10-23
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2133020-7
    ISSN 1741-7007 ; 1741-7007
    ISSN (online) 1741-7007
    ISSN 1741-7007
    DOI 10.1186/s12915-023-01716-w
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Coevolutionary stability of host-symbiont systems with mixed-mode transmission.

    Krishnan, Nandakishor / Rózsa, Lajos / Szilágyi, András / Garay, József

    Journal of theoretical biology

    2023  Volume 576, Page(s) 111620

    Abstract: The coevolution of hosts and symbionts based on virulence and mode of transmission is a complex and diverse biological phenomenon. We introduced a conceptual model to study the stable coexistence and coevolution of an obligate symbiont (mutualist or ... ...

    Abstract The coevolution of hosts and symbionts based on virulence and mode of transmission is a complex and diverse biological phenomenon. We introduced a conceptual model to study the stable coexistence and coevolution of an obligate symbiont (mutualist or parasite) with mixed-mode transmission and its host. Using an age-structured Leslie model for the host, we demonstrated how the obligate symbiont could modify the host's life history traits (survival and fecundity) and the long-term growth rate of the infected lineage. When the symbiont is vertically transmitted, we found that the host and its symbiont could maximize the infected lineage's evolutionary success (multi-level selection). Our model showed that symbionts' effect on host longevity and reproduction might differ, even be opposing, and their net effect might often be counterintuitive. The evolutionary stability of the ecologically stable coexistence was analyzed in the framework of coevolutionary dynamics. Moreover, we found conditions for the ecological and evolutionary stability of the resident host-symbiont pair, which does not allow invasion by rare mutants (each mutant dies out by ecological selection). We concluded that, within the context of our simplified model conditions, a host-symbiont system with mixed-mode transmission is evolutionarily stable unconditionally only if the host can maximize the Malthusian parameters of the infected and non-infected lineages using the same strategy. Finally, we performed a game-theoretical analysis of our selection situation and compared two stability definitions.
    MeSH term(s) Biological Evolution ; Symbiosis ; Reproduction ; Fertility ; Longevity
    Language English
    Publishing date 2023-09-13
    Publishing country England
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2972-5
    ISSN 1095-8541 ; 0022-5193
    ISSN (online) 1095-8541
    ISSN 0022-5193
    DOI 10.1016/j.jtbi.2023.111620
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Book ; Online ; E-Book: Childhood trauma and resilience

    Forkey, Heather C. / Griffin, Jessica L. / Szilagyi, Moira A.

    a practical guide

    2021  

    Author's details Heather C. Forkey, Jessica L. Griffin, Moira Szilagyi
    Language English
    Size 1 Online-Ressource (xi, 224 Seiten), Illustrationen, Diagramme
    Publisher American Academy of Pediatrics
    Publishing place Itasca, IL
    Publishing country United States
    Document type Book ; Online ; E-Book
    Remark Zugriff für angemeldete ZB MED-Nutzerinnen und -Nutzer
    HBZ-ID HT021271680
    ISBN 978-1-61002-507-2 ; 9781610025065 ; 1-61002-507-5 ; 1610025067
    Database ZB MED Catalogue: Medicine, Health, Nutrition, Environment, Agriculture

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  10. Article ; Online: Colorectalis adenocarcinoma implantációs áttéte végbélsipolyban.

    Barcsák, Gábor / Szilágyi, Anna / Jaskó, Róbert / Szigeti, Mikolt / Altorjay, Áron

    Orvosi hetilap

    2023  Volume 164, Issue 3, Page(s) 110–113

    Abstract: In our case report, we describe a rare form of metastatic colorectal carcinoma, in which tumor cells spread intraluminally and metastasis occurs with implantation mechanism far from the primary tumor. A 43-year-old male patient developed perianal abscess. ...

    Title translation Implantation metastasis of colorectal adenocarcinoma in an anal fistula.
    Abstract In our case report, we describe a rare form of metastatic colorectal carcinoma, in which tumor cells spread intraluminally and metastasis occurs with implantation mechanism far from the primary tumor. A 43-year-old male patient developed perianal abscess. After surgical intervention a fistula-in-ano appeared at the site of the abscess. Fistulotomy was performed in another hospital. A few months later, we admitted him to our department with an abnormal tissue proliferation appearing in the surgical area. Histology confirmed adenocarcinoma. Colonoscopy detected tissue proliferation in the sigmoid colon, causing a subtotal stenosis. Laparoscopic rectosigmoid resection and per anum tumor excision were performed. Detailed histological examination confirmed the same mucinous adenocarcinoma in the colon and the anorectal malformation. In this case, implantation mechanism is likely in the development of a synchronous tumor at the site of the fistula-in-ano. Implantation metastasis is considered rare, only a few cases have been reported in the international literature so far. We are not aware of any similar case reported from Hungary. Orv Hetil. 2023; 164(3): 110-113.
    MeSH term(s) Humans ; Male ; Adult ; Anus Neoplasms/etiology ; Anus Neoplasms/pathology ; Anus Neoplasms/surgery ; Abscess/complications ; Adenocarcinoma/pathology ; Rectal Neoplasms/surgery ; Rectal Fistula/surgery ; Rectal Fistula/complications ; Rectal Fistula/pathology
    Language Hungarian
    Publishing date 2023-01-22
    Publishing country Hungary
    Document type Case Reports ; English Abstract ; Journal Article
    ZDB-ID 123879-6
    ISSN 1788-6120 ; 0030-6002
    ISSN (online) 1788-6120
    ISSN 0030-6002
    DOI 10.1556/650.2023.32665
    Database MEDical Literature Analysis and Retrieval System OnLINE

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