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1.
Rev Cardiovasc Med ; 25(5): 185, 2024 May.
Article in English | MEDLINE | ID: mdl-39076488

ABSTRACT

Background: This study investigates the effects of a 12-week circuit exercise program on blood pressure, vascular function, and inflammatory cytokines in older obese women with sarcopenia. Methods: Twenty-eight older obese women with sarcopenia (mean age: 78.2 ± 3.7 years) were randomly divided into an exercise group (EG, n = 14) and a control group (CG, n = 14). The EG participated in a 12-week circuit exercise training regimen, conducted three times weekly, with each session lasting between 45 to 75 minutes (progressively increased over time). The CG was advised to maintain their regular daily routines throughout the intervention period. All dependent variables, including blood pressure, vascular function, and inflammation cytokines, were evaluated pre- and post-intervention. Results: Positive changes were observed in the EG in body composition (body fat mass; p < 0.001, body fat percentage; p < 0.01, free-fat mass; p < 0.01), blood pressure (heart rate; p < 0.05, rate pressure product; p < 0.01), vascular function (brachial-ankle pulse wave velocity; p < 0.05, flow-mediated dilation; p < 0.001), and inflammation cytokines (interleukin-6; p < 0.05). In the CG, there was an increase in body fat mass (p < 0.05) and body fat percentage (p < 0.05), while no changes were observed in other variables. Conclusions: The 12-week circuit exercise program significantly reduced blood pressure, improved vascular function, and decreased inflammatory cytokines in obese older women with sarcopenia. However, individual variations in response highlight the need for personalized exercise regimens.

2.
Neuroimage ; 297: 120737, 2024 Jul 14.
Article in English | MEDLINE | ID: mdl-39004409

ABSTRACT

Alzheimer's disease (AD) is heterogeneous, but existing methods for capturing this heterogeneity through dimensionality reduction and unsupervised clustering have limitations when it comes to extracting intricate atrophy patterns. In this study, we propose a deep learning based self-supervised framework that characterizes complex atrophy features using latent space representation. It integrates feature engineering, classification, and clustering to synergistically disentangle heterogeneity in Alzheimer's disease. Through this representation learning, we trained a clustered latent space with distinct atrophy patterns and clinical characteristics in AD, and replicated the findings in prodromal Alzheimer's disease. Moreover, we discovered that these clusters are not solely attributed to subtypes but also reflect disease progression in the latent space, representing the core dimensions of heterogeneity, namely progression and subtypes. Furthermore, longitudinal latent space analysis revealed two distinct disease progression pathways: medial temporal and parietotemporal pathways. The proposed approach enables effective latent representations that can be integrated with individual-level cognitive profiles, thereby facilitating a comprehensive understanding of AD heterogeneity.

3.
Healthcare (Basel) ; 12(13)2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38998775

ABSTRACT

Nitrate-rich beetroot juice (NRBRJ) can potentially enhance exercise performance and improve cardiovascular function, leading to an increased use of NRBRJ over the years. However, the combined effects of NRBRJ supplementation and exercise on cardiovascular function remain unclear. Therefore, this study compared cardiovascular function responses to submaximal exercise with either placebo (PLA) or NRBRJ supplementation in healthy men. Twelve healthy men (aged 25.2 ± 2.3 years) completed the 30-min submaximal cycle ergometer exercise trials corresponding to 70% maximal heart rate (HRmax) with either PLA or NRBRJ supplementation in a random order. The mean exercise load, heart rate (HR), stroke volume (SV), cardiac output (CO), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and total peripheral resistance (TPR) were measured during exercise. The brachial-ankle pulse wave velocity (baPWV) and flow-mediated dilation (FMD) were measured before and after exercise. NRBRJ supplementation was more effective than PLA in increasing the mean exercise load and decreasing DBP and MAP during submaximal exercise. Furthermore, baPWV decreased in the NRBRJ trial and was considerably lower after exercise in the NRBRJ-supplemented group than in the PLA-supplemented group. FMD significantly increased in the PLA and NRBRJ trials; however, NRBRJ supplementation demonstrated a significantly higher FMD before and after exercise than PLA supplementation. In conclusion, acute NRBRJ supplementation and exercise were more effective than PLA supplementation and exercise in improving aerobic exercise capacity and cardiovascular function in healthy men.

4.
Yonsei Med J ; 65(8): 434-447, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39048319

ABSTRACT

PURPOSE: Alzheimer's disease (AD) dementia may not be a single disease entity. Early-onset AD (EOAD) and late-onset AD (LOAD) have been united under the same eponym of AD until now, but disentangling the heterogeneity according to the age of sonset has been a major tenet in the field of AD research. MATERIALS AND METHODS: Ninety-nine patients with AD (EOAD, n=54; LOAD, n=45) and 66 cognitively normal controls completed both [18F]THK5351 and [18F]flutemetamol (FLUTE) positron emission tomography scans along with structural magnetic resonance imaging and detailed neuropsychological tests. RESULTS: EOAD patients had higher THK retention in the precuneus, parietal, and frontal lobe, while LOAD patients had higher THK retention in the medial temporal lobe. Intravoxel correlation analyses revealed that EOAD presented narrower territory of local FLUTE-THK correlation, while LOAD presented broader territory of correlation extending to overall parieto-occipito-temporal regions. EOAD patients had broader brain areas which showed significant negative correlations between cortical thickness and THK retention, whereas in LOAD, only limited brain areas showed significant correlation with THK retention. In EOAD, most of the cognitive test results were correlated with THK retention. However, a few cognitive test results were correlated with THK retention in LOAD. CONCLUSION: LOAD seemed to show gradual increase in tau and amyloid, and those two pathologies have association to each other. On the other hand, in EOAD, tau and amyloid may develop more abruptly and independently. These findings suggest LOAD and EOAD may have different courses of pathomechanism.


Subject(s)
Alzheimer Disease , Atrophy , Brain , Magnetic Resonance Imaging , Positron-Emission Tomography , tau Proteins , Humans , Alzheimer Disease/pathology , Alzheimer Disease/diagnostic imaging , Male , Female , tau Proteins/metabolism , Aged , Atrophy/pathology , Brain/pathology , Brain/diagnostic imaging , Middle Aged , Neuropsychological Tests , Aniline Compounds , Age of Onset , Amyloid/metabolism , Aged, 80 and over , Benzothiazoles , Aminopyridines , Quinolines
5.
Phys Act Nutr ; 28(1): 1-6, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38719460

ABSTRACT

PURPOSE: This study investigated the effects of exogenous lactate intake on energy metabolism during 1 h of rest after acute exercise. METHODS: Eight-week-old ICR mice were randomly divided into four groups: SED (no treatment), EXE (exercise only), LAC (post-exercise oral lactate administration), and SAL (post-exercise saline administration) (n=8 per group). The exercise intensity was at VO2max 80% at 25 m/min and 15° slope for 50 min. After acute exercise, the LAC and SAL groups ingested lactate and saline orally, respectively, and were allowed to rest in a chamber. Energy metabolism was measured for 1 h during the resting period. RESULTS: LAC and SAL group mice ingested lactate and saline, respectively, after exercise and the blood lactate concentration was measured 1 h later through tail blood sampling. Blood lactate concentration was not significantly different between the two groups. Energy metabolism measurements under stable conditions revealed that the respiratory exchange ratio in the LAC group was significantly lower than that in the SAL group. Additionally, carbohydrate oxidation in the LAC group was significantly lower than that in the SAL group at 10-25 min. No significant difference was observed in the fat oxidation level between the two groups. CONCLUSION: We found that post-exercise lactate intake modified the respiratory exchange ratio after 1 h of rest. In addition, acute lactate ingestion inhibits carbohydrate oxidation during the post-exercise recovery period.

6.
Phys Act Nutr ; 28(1): 31-36, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38719464

ABSTRACT

PURPOSE: Public transportation (PT) systems significantly shape urban mobility and have garnered attention owing to their potential impact on public health, particularly the promotion of physical activity. Beyond their transportation functions, PT systems also affect daily energy expenditure through non-exercise activity thermogenesis (NEAT). This mini-review surveys the existing literature to explore the effects of PT use on NEAT levels and subsequent health outcomes. METHODS: A comprehensive literature search was conducted using the electronic databases PubMed, Google Scholar, and Web of Science. Keywords including "public transportation," "non-exercise activity thermogenesis," "physical activity," "health promotion," and related terms were used to identify relevant studies. RESULTS: This review highlights the multifaceted relationship between PT use and health promotion, emphasizing the potential benefits and challenges of increasing NEAT through public transit utilization. Overall, the findings suggest that PT use contributes positively to NEAT levels, and thus improves health outcomes. However, the extent of this impact may vary depending on individual and contextual factors. CONCLUSION: Interventions promoting active transportation modes, including public transit, hold promise for addressing sedentary behavior and fostering healthier lifestyles at the population level.

7.
Metabolites ; 14(4)2024 Apr 13.
Article in English | MEDLINE | ID: mdl-38668348

ABSTRACT

We compared the effects of chronic exogenous lactate and exercise training, which influence energy substrate utilization and body composition improvements at rest and during exercise, and investigated the availability of lactate as a metabolic regulator. The mice were divided into four groups: CON (sedentary + saline), LAC (sedentary + lactate), EXE (exercise + saline), and EXLA (exercise + lactate). The total experimental period was set at 4 weeks, the training intensity was set at 60-70% VO2max, and each exercise group was administered a solution immediately after exercise. Changes in the energy substrate utilization at rest and during exercise, the protein levels related to energy substrate utilization in skeletal muscles, and the body composition were measured. Lactate intake and exercise increased carbohydrate oxidation as a substrate during exercise, leading to an increased energy expenditure and increased protein levels of citrate synthase and malate dehydrogenase 2, key factors in the TCA(tricarboxylic acid) cycle of skeletal muscle. Exercise, but not lactate intake, induced the upregulation of the skeletal muscle glucose transport factor 4 and a reduction in body fat. Hence, chronic lactate administration, as a metabolic regulator, influenced energy substrate utilization by the skeletal muscle and increased energy expenditure during exercise through the activation of carbohydrate metabolism-related factors. Therefore, exogenous lactate holds potential as a metabolic regulator.

8.
Dialogues Health ; 4: 100161, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38516218

ABSTRACT

This cross-sectional, descriptive study conducted on in June 2022 reviewed 100 TikTok videos using the hashtag #africansinukriane that depicted discrimination against Black people attempting to flee Ukraine at the onset of the war in February 2022. Two of the 16 themes were significant and present in over 50% of videos: raising awareness (67%) and racial discrimination (64%). Videos with elements of physical contact (N = 16, 76.2%), violence (N = 12, 75%), and dehumanization (N = 11, 68.8%) had higher shares than overall media shares. Less than 10% of the videos included dark humor (8%), sharing helpful resources (7%), and appreciation of countries that offered support (5%). Results indicate that videos that include raising awareness (p = .02), racial discrimination (p = .001), on-scene clips or war scenes (p = .007), physical contact (p = .006), and denied entry (p = .022). Their estimated differences in locations indicate that all of these themes were related to higher median shares of the videos. This study supports that TikTok is a place where marginalized groups can raise awareness about injustice and create counternarratives. This study exemplifies international anti-blackness with implications for health marketing and communication, human rights efforts, refugee health, and targeted mental health and policy support for those displaced by war.

9.
Article in English | MEDLINE | ID: mdl-38411502

ABSTRACT

Rotator cuff tear (RCT) is the most common cause of disability in the upper extremity. It results in 4.5 million physician visits in the United States every year and is the most common etiology of shoulder conditions evaluated by orthopedic surgeons. Over 460,000 RCT repair surgeries are performed in the United States annually. Rotator cuff (RC) retear and failure to heal remain significant postoperative complications. Literature suggests that the retear rates can range from 29.5% to as high as 94%. Weakened and irregular enthesis regeneration is a crucial factor in postsurgical failure. Although commercially available RC repair grafts have been introduced to augment RC enthesis repair, they have been associated with mixed clinical outcomes. These grafts lack appropriate biological cues such as stem cells and signaling molecules at the bone-tendon interface. In addition, they do little to prevent fibrovascular scar tissue formation, which causes the RC to be susceptible to retear. Advances in tissue engineering have demonstrated that mesenchymal stem cells (MSCs) and growth factors (GFs) enhance RC enthesis regeneration in animal models. These models show that delivering MSCs and GFs to the site of RCT enhances native enthesis repair and leads to greater mechanical strength. In addition, these models demonstrate that MSCs and GFs may be delivered through a variety of methods including direct injection, saturation of repair materials, and loaded microspheres. Grafts that incorporate MSCs and GFs enhance anti-inflammation, osteogenesis, angiogenesis, and chondrogenesis in the RC repair process. It is crucial that the techniques that have shown success in animal models are incorporated into the clinical setting. A gap currently exists between the promising biological factors that have been investigated in animal models and the RC repair grafts that can be used in the clinical setting. Future RC repair grafts must allow for stable implantation and fixation, be compatible with current arthroscopic techniques, and have the capability to deliver MSCs and/or GFs.

10.
Int J Mol Sci ; 25(2)2024 Jan 06.
Article in English | MEDLINE | ID: mdl-38255823

ABSTRACT

The implantation of good-quality embryos to the receptive endometrium is essential for successful live birth through in vitro fertilization (IVF). The higher the quality of embryos, the higher the live birth rate per cycle, and so efforts have been made to obtain as many high-quality embryos as possible after fertilization. In addition to an effective controlled ovarian stimulation process to obtain high-quality embryos, the composition of the embryo culture medium in direct contact with embryos in vitro is also important. During embryonic development, under the control of female sex hormones, the fallopian tubes and endometrium create a microenvironment that supplies the nutrients and substances necessary for embryos at each stage. During this process, the development of the embryo is finely regulated by signaling molecules, such as growth factors and cytokines secreted from the epithelial cells of the fallopian tube and uterine endometrium. The development of embryo culture media has continued since the first successful human birth through IVF in 1978. However, there are still limitations to mimicking a microenvironment similar to the reproductive organs of women suitable for embryo development in vitro. Efforts have been made to overcome the harsh in vitro culture environment and obtain high-quality embryos by adding various supplements, such as antioxidants and growth factors, to the embryo culture medium. Recently, there has been an increase in the number of studies on the effect of supplementation in different clinical situations such as old age, recurrent implantation failure (RIF), and unexplained infertility; in addition, anticipation of the potential benefits from individuation is rising. This article reviews the effects of representative supplements in culture media on embryo development.


Subject(s)
Granulocyte-Macrophage Colony-Stimulating Factor , Melatonin , Female , Humans , Pregnancy , Culture Media/chemistry , Culture Media/pharmacology , Cytokines , Insulin-Like Growth Factor I , Melatonin/pharmacology
11.
Adv Mater ; 36(16): e2311719, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38214475

ABSTRACT

The burgeoning demand for commercializing self-luminescing quantum dot (QD) light-emitting diodes (LEDs) has stimulated extensive research into environmentally friendly and efficient QD materials. Hydrofluoric acid (HF) additive improves photoluminescence (PL) properties of blue-emitting ZnSeTe QDs, ultimately reaching a remarkable quantum yield (QY) of 97% with an ultranarrow peak width of 14 nm after sufficient HF addition. The improvement in optical properties of the QDs is accompanied by a morphology change of the particles, forming cubic-shaped defect-free ZnSeTe QDs characterized by a zinc blende (ZB) crystal structure. This treatment improves the QD-emitting properties by facilitating facet-specific growth, selectively exposing stabilized (100) facets, and reducing the lattice disorders. The facet-specific growth process gives rise to defect-free monodispersed cubic dots that exhibit remarkably narrow and homogeneous PL spectra. Meticulous time-resolved spectroscopic studies allow an understanding of the correlation between ZnSeTe QDs' particle shape and performance following HF addition. These investigations shed light on the intricacies of the growth mechanism and the factors influencing the PL efficiency of the resulting QDs. The findings significantly contribute to understanding the role of HF treatment in tailoring the optical properties of ZnSeTe QDs, thereby bringing it closer to the realization of highly efficient and bright QD-LEDs for various practical applications.

12.
Phys Act Nutr ; 27(3): 36-43, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37946445

ABSTRACT

PURPOSE: This review aimed to investigate the effects of vitamin C and glutathione supplementation on exercise performance. METHODS: We conducted a literature search across the PubMed, Google Scholar, and Web of Science databases using the keywords vitamin C, glutathione, antioxidants, exercise, and oxidative stress. RESULTS: The effects of vitamin C supplementation on exercise performance and oxidative stress levels are inconsistent. Glutathione, with its diverse forms of supplementation and methods, presents mixed outcomes. Vitamin C and glutathione have deeply interconnected antioxidant functions and are mutually essential to each other. Research investigating the combined intake of these two substances, which are intricately linked biochemically, and their effects on exercise performance remain largely unexplored. CONCLUSION: Studies on the effects of vitamin C and glutathione intake on exercise have been conducted using diverse approaches; however, the results have not been consistent. Although an additive effect is anticipated with the combined intake of vitamin C and glutathione, research on this topic is currently insufficient, and further studies are required.

13.
Phys Act Nutr ; 27(3): 64-70, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37946448

ABSTRACT

PURPOSE: This study aimed to evaluate the effects of 12 weeks of non-face-to-face exercise intervention using mobile health (mHealth) on blood lipid levels and health-related physical fitness in obese women. METHODS: Thirty obese women (aged: 39.40 ± 11.07 years, percent body fat: 37.05 ± 5.15%) were enrolled, and all completed the study. Non-face-to-face exercises were performed for 12 weeks using a mHealth and smart tracker (Charge 4, Fitbit, USA). Participants were randomly assigned to an experimental (EXP) or control (CON) group. The 12-week exercise program using mHealth included resistance (twice a week for 60 min), aerobics (five times a week for 50 min), and flexibility (five times a week for 10 min). RESULTS: The results showed that high-density lipoprotein cholesterol (Post - Pre: 9.07 mg·dL-1, p < 0.001) and ratio of low-density to high-density lipoprotein cholesterol (Post - Pre: -0.71 mg·dL-1, p < 0.05) significantly changed during the intervention period in EXP. There were significant increases in sit-ups (Post - Pre: 7.73 numbers, p < 0.001), grip strength (Post - Pre: 2.92 kg, p < 0.001), and sit and reach (Post - Pre: 2.51 cm, p < 0.01) in EXP. CONCLUSION: Non-face-to-face exercise using mHealth for 12 weeks improved blood lipid levels and health-related physical fitness; therefore, it can help improve compliance through self-monitoring and lifestyle changes by increasing physical activity.

14.
Int J Mol Sci ; 24(21)2023 Oct 24.
Article in English | MEDLINE | ID: mdl-37958518

ABSTRACT

Pigs are susceptible to cold stress due to the absence of brown fat caused by the partial deletion of uncoupling protein 1 during their evolution. Some local pig breeds in China exhibit potential cold adaptability, but research has primarily focused on fat and intestinal tissues. Skeletal muscle plays a key role in adaptive thermogenesis in mammals, yet the molecular mechanism of cold adaptation in porcine skeletal muscle remains poorly understood. This study investigated the cold adaptability of two pig breeds, Mashen pigs (MS) and Large White pigs (LW), in a four-day cold (4 °C) or normal temperature (25 °C) environment. We recorded phenotypic changes and collected blood and longissimus dorsi muscle for transcriptome sequencing. Finally, the PRSS8 gene was randomly selected for functional exploration in porcine skeletal muscle satellite cells. A decrease in body temperature and body weight in both LW and MS pigs under cold stress, accompanied by increased shivering frequency and respiratory frequency, were observed. However, the MS pigs demonstrated stable physiological homeostasis, indicating a certain level of cold adaptability. The LW pigs primarily responded to cold stress by regulating their heat production and glycolipid energy metabolism. The MS pigs exhibited a distinct response to cold stress, involving the regulation of heat production, energy metabolism pathways, and robust mitochondrial activity, as well as a stronger immune response. Furthermore, the functional exploration of PRSS8 in porcine skeletal muscle satellite cells revealed that it affected cellular energy metabolism and thermogenesis by regulating ERK phosphorylation. These findings shed light on the diverse transcriptional responses of skeletal muscle in LW and MS pigs under cold stress, offering valuable insights into the molecular mechanisms underlying cold adaptation in pigs.


Subject(s)
Cold-Shock Response , Thermogenesis , Swine , Animals , Cold-Shock Response/genetics , Thermogenesis/genetics , Gene Expression Profiling , Body Weight , Muscle, Skeletal/metabolism , Mammals
15.
Healthcare (Basel) ; 11(20)2023 Oct 19.
Article in English | MEDLINE | ID: mdl-37893842

ABSTRACT

With the emergence of coronavirus disease 2019, individuals have been participating in online exercises to maintain their health while avoiding infection. Among these online exercises, Pilates intervention is a popular modality. This study aimed to examine the differences between online and face-to-face Pilates interventions in terms of various physiological parameters and included 30 middle-aged individuals (age 43.3 ± 5.5 years) with obesity. These individuals were randomly divided into a face-to-face Pilates group (FPG), an online Pilates group (OPG), and a control group (CG). The FPG and OPG performed a 60-min mat Pilates program with a Borg scale of 11-17, three times a week for 12 weeks. The participants in the CG maintained their daily routines. Body composition, mechanical muscle properties, cardiometabolic parameters, mental health, and physical fitness were assessed before and after 12 weeks of intervention. No significant differences in body composition or cardiometabolic parameters were observed between groups. However, the FPG and OPG showed greater improvements than the CG in terms of muscle mechanical properties, cardiometabolic parameters, mental health, and physical fitness. In addition, the FPG showed greater improvement than the OPG. In conclusion, face-to-face Pilates is a more effective modality than online Pilates, although both modalities improve health-related parameters.

16.
Artif Intell Med ; 144: 102654, 2023 10.
Article in English | MEDLINE | ID: mdl-37783547

ABSTRACT

Amyloid positivity is an early indicator of Alzheimer's disease and is necessary to determine the disease. In this study, a deep generative model is utilized to predict the amyloid positivity of cognitively normal individuals using proxy measures, such as structural MRI scans, demographic variables, and cognitive scores, instead of invasive direct measurements. Through its remarkable efficacy in handling imperfect datasets caused by missing data or labels, and imbalanced classes, the model outperforms previous studies and widely used machine learning approaches with an AUROC of 0.8609. Furthermore, this study illuminates the model's adaptability to diverse clinical scenarios, even when feature sets or diagnostic criteria differ from the training data. We identify the brain regions and variables that contribute most to classification, including the lateral occipital lobes, posterior temporal lobe, and APOE ϵ4 allele. Taking advantage of deep generative models, our approach can not only provide inexpensive, non-invasive, and accurate diagnostics for preclinical Alzheimer's disease, but also meet real-world requirements for clinical translation of a deep learning model, including transferability and interpretability.


Subject(s)
Alzheimer Disease , Cognitive Dysfunction , Humans , Alzheimer Disease/diagnostic imaging , Alzheimer Disease/genetics , Cognitive Dysfunction/diagnosis , Brain/diagnostic imaging , Magnetic Resonance Imaging , Machine Learning
17.
Sensors (Basel) ; 23(19)2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37836879

ABSTRACT

Issues of fairness and consistency in Taekwondo poomsae evaluation have often occurred due to the lack of an objective evaluation method. This study proposes a three-dimensional (3D) convolutional neural network-based action recognition model for an objective evaluation of Taekwondo poomsae. The model exhibits robust recognition performance regardless of variations in the viewpoints by reducing the discrepancy between the training and test images. It uses 3D skeletons of poomsae unit actions collected using a full-body motion-capture suit to generate synthesized two-dimensional (2D) skeletons from desired viewpoints. The 2D skeletons obtained from diverse viewpoints form the training dataset, on which the model is trained to ensure consistent recognition performance regardless of the viewpoint. The performance of the model was evaluated against various test datasets, including projected 2D skeletons and RGB images captured from diverse viewpoints. Comparison of the performance of the proposed model with those of previously reported action recognition models demonstrated the superiority of the proposed model, underscoring its effectiveness in recognizing and classifying Taekwondo poomsae actions.

18.
Phys Act Nutr ; 27(2): 13-18, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37583067

ABSTRACT

PURPOSE: The purpose of the study was to investigate the effects of 4 weeks of lactate intake immediately after endurance exercise on maximal oxygen uptake (VO2max) in exercise performance. METHODS: Seven-week-old mice from the Institute of Cancer Research (ICR) were randomly divided into four groups: vehicle intake (SE/CON), lactate intake (SE/LAC), endurance exercise with vehicle intake (EX/ CON), and lactate intake with endurance exercise (EX/ LAC). Mice were subjected to 60-70% VO2max endurance exercise with or without oral lactate intake 5 days/ week for 4 weeks. VO2max measurements (VO2max, time to exhaustion (TTE), respiratory exchange rate, fat oxidation, and carbohydrate oxidation) were recorded at the end of the study period. After 48 h of VO2max measurement, the mice were sacrificed, and three different abdominal fat samples (epididymal, perirenal, and mesenteric) were collected. RESULTS: Body weight and abdominal fat mass did not differ between the groups. When measuring VO2max, endurance exercise raised VO2max, and lactate intake after endurance exercise increased TTE. The change in energy substrate utilization during VO2max measurement demonstrated that although the respiratory exchange rate and fat oxidation were enhanced by lactate intake, there were no synergistic effects of lactate intake and endurance exercise. CONCLUSION: Lactate intake immediately after endurance exercises can improve exercise performance, indicating the benefit of long-term exogenous lactate intake as an exercise supplement.

19.
Nutrients ; 15(15)2023 Jul 26.
Article in English | MEDLINE | ID: mdl-37571262

ABSTRACT

This study investigated the acute effects of natural antioxidants, derived from yeast fermentation containing glutathione and dietary vitamin C supplementation, on metabolic function, skeletal muscle oxygenation, cardiac function, and antioxidant function during submaximal exercise in middle-aged triathlon athletes. Twelve participants (aged 49.42 ± 5.9 years) completed 90 min submaximal cycling trials corresponding to 70% maximal oxygen uptake with either vitamin C and glutathione (VitC+Glu), vitamin C (VitC), glutathione (Glu) supplementation, or placebo. Metabolic function (minute ventilation, oxygen uptake, carbon dioxide output [VCO2], respiratory exchange ratio [RER], oxygen pulse [O2pulse], carbohydrate oxidation, fat oxidation, and energy expenditure), skeletal muscle oxygenation (oxidized hemoglobin and myoglobin in skeletal muscle tissue, total hemoglobin and myoglobin in skeletal muscle tissue [tHb]), cardiac function (heart rate [HR], stroke volume [SV], cardiac output, end-diastolic volume, end-systolic volume, and ejection fraction), and antioxidant function parameters (blood lactate, superoxide dismutase, catalase, glutathione peroxidases, glutathione [GSH], diacron reactive oxygen metabolite [dROM], and biological antioxidant potential [BAP]) were measured during submaximal exercise and recovery. VCO2, RER, HR, blood lactate after exercise, and dROM were significantly lower, and O2pulse, tHb, and BAP were significantly higher for VitC+Glu than for the other trials (p < 0.05). In conclusion, combined vitamin C and glutathione supplementation was more effective in improving metabolic function, skeletal oxygenation, cardiac function, and antioxidant function during prolonged submaximal exercise in middle-aged triathletes.


Subject(s)
Antioxidants , Athletic Performance , Humans , Middle Aged , Antioxidants/pharmacology , Ascorbic Acid , Saccharomyces cerevisiae/metabolism , Cross-Over Studies , Fermentation , Myoglobin/metabolism , Vitamins/pharmacology , Glutathione/metabolism , Muscle, Skeletal/metabolism , Athletes , Oxygen/metabolism , Lactates/metabolism , Dietary Supplements
20.
Med Phys ; 50(11): 7203-7213, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37517077

ABSTRACT

BACKGROUND: Many studies have utilized optical camera systems with volumetric scintillators for quality assurances (QA) to estimate the proton beam range. However, previous analytically driven range estimation methods have the difficulty to derive the dose distributions from the scintillation images with quenching and optical effects. PURPOSE: In this study, a deep learning method utilized to QA was used to predict the beam range and spread-out Bragg peak (SOBP) for two-dimensional (2D) map conversion from the scintillation light distribution (LD) into the dose distribution in a water phantom. METHODS: The 2D residual U-net modeling for deep learning was used to predict the 2D water dose map from a 2D scintillation LD map. Monte Carlo simulations for dataset preparation were performed with varying monoenergetic proton beam energies, field sizes, and beam axis shifts. The LD was reconstructed using photons backpropagated from the aperture as a virtual lens. The SOBP samples were constructed based on monoenergetic dose distributions. The training set, including the validation set, consisted of 8659 image pairs of LD and water dose maps. After training, dose map prediction was performed using a 300 image pair test set generated under random conditions. The pairs of simulated and predicted dose maps were analyzed by Bragg peak fitting and gamma index maps to evaluate the model prediction. RESULT: The estimated beam range and SOBP width resolutions were 0.02 and 0.19 mm respectively for varying beam conditions, and the beam range and SOBP width deviations from the reference simulation result were less than 0.1 and 0.8 mm respectively. The simulated and predicted distributions showed good agreement in the gamma analysis, except for rare cases with failed gamma indices in the proximal and field-marginal regions. CONCLUSION: The deep learning conversion method using scintillation LDs in an optical camera system with a scintillator is feasible for estimating proton beam range and SOBP width with high accuracy.


Subject(s)
Deep Learning , Proton Therapy , Protons , Proton Therapy/methods , Computer Simulation , Monte Carlo Method , Water , Radiotherapy Dosage
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