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1.
Cancers (Basel) ; 16(10)2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38791998

RESUMO

Cancer cachexia is a multifaceted syndrome that impacts individuals with advanced cancer. It causes numerous pathological changes in cancer patients, such as inflammation and metabolic dysfunction, which further diminish their quality of life. Unfortunately, cancer cachexia also increases the risk of mortality in affected individuals, making it an important area of focus for cancer research and treatment. Several potential nutritional therapies are being tested in preclinical and clinical models for their efficacy in improving muscle metabolism in cancer patients. Despite promising results, no special nutritional therapies have yet been validated in clinical practice. Multiple studies provide evidence of the benefits of increasing muscle protein synthesis through an increased intake of amino acids or protein. There is also increasing evidence that exercise can reduce muscle atrophy by modulating protein synthesis. Therefore, the combination of protein intake and exercise may be more effective in improving cancer cachexia. This review provides an overview of the preclinical and clinical approaches for the use of amino acids with and without exercise therapy to improve muscle metabolism in cachexia.

2.
Sci Rep ; 14(1): 7002, 2024 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523136

RESUMO

We analyze time-averaged experimental data from in vitro activities of neuronal networks. Through a Pairwise Maximum-Entropy method, we identify through an inverse binary Ising-like model the local fields and interaction couplings which best reproduce the average activities of each neuron as well as the statistical correlations between the activities of each pair of neurons in the system. The specific information about the type of neurons is mainly stored in the local fields, while a symmetric distribution of interaction constants seems generic. Our findings demonstrate that, despite not being directly incorporated into the inference approach, the experimentally observed correlations among groups of three neurons are accurately captured by the derived Ising-like model. Within the context of the thermodynamic analogy inherent to the Ising-like models developed in this study, our findings additionally indicate that these models demonstrate characteristics of second-order phase transitions between ferromagnetic and paramagnetic states at temperatures above, but close to, unity. Considering that the operating temperature utilized in the Maximum-Entropy method is T o = 1 , this observation further expands the thermodynamic conceptual parallelism postulated in this work for the manifestation of criticality in neuronal network behavior.


Assuntos
Neurônios , Neurônios/fisiologia , Termodinâmica , Entropia , Temperatura
3.
Rev Sci Instrum ; 94(4)2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38081277

RESUMO

High-energy γ rays generated from inertial confinement fusion (ICF) experiments have become an important signature for studying the dynamics of implosion processes. Due to their high-energy and penetrating nature, γ rays are the most unperturbed fusion products, which can preserve the original birth information of the fusion process. Fusion γ rays provide a direct measure of nuclear reaction rates (unlike x rays) without being compromised by Doppler spreading (unlike neutrons). However, unambiguous γ-ray measurements for ICF study further required a decade-long period of technological development, which included a deepening understanding of fusion γ-ray characteristics and innovations in instrument performance. This review article introduces the production mechanism of the prompt and secondary γ rays and various ICF performance parameters (e.g., bang time and burn width), which can be derived from γ-ray measurement. A technical overview will be followed by summarizing γ-ray detectors fielded or proposed, especially for high-yield ICF experiments at the Omega Laser Facility and National Ignition Facility. Over the past few years, γ-ray diagnostic technologies have been extended beyond ICF research. A few examples of non-ICF applications of γ-ray detectors are introduced at the end of this article.

4.
Cell Rep ; 42(10): 113162, 2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37777965

RESUMO

Alpha oscillations are a distinctive feature of the awake resting state of the human brain. However, their functional role in resting-state neuronal dynamics remains poorly understood. Here we show that, during resting wakefulness, alpha oscillations drive an alternation of attenuation and amplification bouts in neural activity. Our analysis indicates that inhibition is activated in pulses that last for a single alpha cycle and gradually suppress neural activity, while excitation is successively enhanced over a few alpha cycles to amplify neural activity. Furthermore, we show that long-term alpha amplitude fluctuations-the "waxing and waning" phenomenon-are an attenuation-amplification mechanism described by a power-law decay of the activity rate in the "waning" phase. Importantly, we do not observe such dynamics during non-rapid eye movement (NREM) sleep with marginal alpha oscillations. The results suggest that alpha oscillations modulate neural activity not only through pulses of inhibition (pulsed inhibition hypothesis) but also by timely enhancement of excitation (or disinhibition).


Assuntos
Descanso , Vigília , Humanos , Vigília/fisiologia , Descanso/fisiologia , Neurônios , Encéfalo/fisiologia , Eletroencefalografia/métodos
5.
Antioxidants (Basel) ; 12(10)2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37891926

RESUMO

Oxidative stress (OS) and inflammation are features of metabolic syndrome (MetS) that can contribute to the shortening of telomere length (TL), a marker of cellular ageing. Research indicates that exercise can positively influence MetS-associated conditions and TL. However, the effects of low-volume exercise types on TL are still unknown. We investigated the impact of very-low-volume high-intensity interval training (LV-HIIT), one-set resistance training (1-RT), and whole-body electromyostimulation (WB-EMS) on TL, inflammation, and cardiometabolic indices in 167 MetS patients. Data were derived from two randomized controlled trials where patients were allocated to an exercise group (2 sessions/week, for 12 weeks) or a control group. All groups received standard-care nutritional weight loss counselling. TL was determined as the T/S ratio (telomere to single-copy gene amount). All groups significantly reduced body weight (p < 0.05), but the T/S-ratio (p < 0.001) only increased with LV-HIIT. OS-related inflammatory markers (C-reactive protein, interleukin-6, and lipopolysaccharide-binding protein) only decreased (p < 0.05) following LV-HIIT. The MetS severity z-score improved with LV-HIIT (p < 0.001) and 1-RT (p = 0.014) but not with WB-EMS. In conclusion, very-low-volume exercise modalities have differential effects on telomeres, inflammation, and cardiometabolic health. Only LV-HIIT but not strength-based low-volume exercise increased TL in MetS patients, presumably due to superior effects on OS-related inflammatory markers.

6.
J Imaging ; 9(8)2023 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-37623689

RESUMO

Nano-computed tomography (nano-CT) based on scanning electron microscopy (SEM) is utilized for multimodal material characterization in one instrument. Since SEM-based CT uses geometrical magnification, X-ray targets can be adapted without any further changes to the system. This allows for designing targets with varying geometry and chemical composition to influence the X-ray focal spot, intensity and energy distribution with the aim to enhance the image quality. In this paper, three different target geometries with a varying volume are presented: bulk, foil and needle target. Based on the analyzed electron beam properties and X-ray beam path, the influence of the different target designs on X-ray imaging is investigated. With the obtained information, three targets for different applications are recommended. A platinum (Pt) bulk target tilted by 25° as an optimal combination of high photon flux and spatial resolution is used for fast CT scans and the investigation of high-absorbing or large sample volumes. To image low-absorbing materials, e.g., polymers or organic materials, a target material with a characteristic line energy right above the detector energy threshold is recommended. In the case of the observed system, we used a 30° tilted chromium (Cr) target, leading to a higher image contrast. To reach a maximum spatial resolution of about 100 nm, we recommend a tungsten (W) needle target with a tip diameter of about 100 nm.

7.
Nutrients ; 15(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513591

RESUMO

Malnutrition and cancer cachexia are highly prevalent comorbidities of cancer, limiting patients' quality of life and being relevant to prognosis. International and national clinical guidelines recommend supportive nutrition and exercise therapy for cancer patients. However, there is little current epidemiological evidence on the implementation of these guideline recommendations in clinical routine. To close this data gap, a national survey in Germany using an online questionnaire was conducted. There were 261 of a total of 5074 contacted hospitals and medical offices who participated in the survey (5.1% response rate). The data indicated that nutrition and exercise therapy for cancer patients is so far inadequately implemented, with 59% of the respondents reporting nutrition therapy as an integral part of oncological treatment, 66.7% having a nutrition specialist/team, and 65.1% routinely conducting a screening for nutritional status. Only half of the participants stated that there are defined goals in nutrition therapy. The majority of respondents (85.8%) generally recommend exercise therapy, but only a few of them provide specific offers at their own institution (19.6%) or at cooperation partners (31.7%). In order to implement the recommended combined nutrition and exercise therapy as part of regular care, there is a need for nationwide availability of multidisciplinary nutrition teams and targeted offers of individualized exercise therapy. Health policy support would be important to create the structural, financial, and staff conditions for appropriate guideline implementation in order to achieve the optimal treatment of cancer patients.


Assuntos
Desnutrição , Neoplasias , Humanos , Qualidade de Vida , Apoio Nutricional , Desnutrição/diagnóstico , Neoplasias/complicações , Neoplasias/terapia , Terapia por Exercício
8.
Sensors (Basel) ; 23(14)2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37514664

RESUMO

For high-performance thermoplastic materials, material behavior results from the degree of crystallization and the distribution of crystalline phases. Due to the less stiff amorphous and the stiffer and anisotropic crystalline phases, the microstructural properties are inhomogeneous. Thus, imaging of the microstructure is an important tool to characterize the process-induced morphology and the resulting properties. Using focusing ultrasonic transducers with high frequency (25 MHz nominal center frequency) enables the imaging of specimens with high lateral resolution, while wave propagation is related to the elastic modulus, density and damping of the medium. The present work shows experimental results of high-frequency ultrasonic spectroscopy (HF-US) applied to injection-molded polyether-ether-ketone (PEEK) tensile specimens with different process-related morphologies. This work presents different analysis procedures, e.g., backwall echo, time of flight and Fourier-transformed time signals, facilitating the mapping of gradual mechanical properties and assigning them to different crystalline content and morphological zones.

9.
Phys Rev E ; 107(6-1): 064307, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37464662

RESUMO

The relation between spontaneous and stimulated brain activity is a fundamental question in neuroscience which has received wide attention in experimental studies. Recently, it has been suggested that the evoked response to external stimuli can be predicted from temporal correlations of spontaneous activity. Previous theoretical results, confirmed by the comparison with magnetoencephalography data for human brains, were obtained for the Wilson-Cowan model in the condition of balance of excitation and inhibition, a signature of a healthy brain. Here we extend previous studies to imbalanced conditions by examining a region of parameter space around the balanced fixed point. Analytical results are compared to numerical simulations of Wilson-Cowan networks. We evidence that in imbalanced conditions the functional form of the time correlation and response functions can show several behaviors, exhibiting also an oscillating regime caused by the emergence of complex eigenvalues. The analytical predictions are fully in agreement with numerical simulations, validating the role of cross-correlations in the response function. Furthermore, we identify the leading role of inhibitory neurons in controlling the overall activity of the system, tuning the level of excitability and imbalance.


Assuntos
Encéfalo , Neurônios , Humanos , Neurônios/fisiologia , Encéfalo/fisiologia
10.
Virus Res ; 333: 199144, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37271420

RESUMO

A sentinel plot case study was carried out to identify and map the distribution of begomovirus-betasatellite complexes in sentinel plots and commercial cotton fields over a four-year period using molecular and high-throughput DNA 'discovery' sequencing approaches. Samples were collected from 15 study sites in the two major cotton-producing areas of Pakistan. Whitefly- and leafhopper-transmitted geminiviruses were detected in previously unreported host plant species and locations. The most prevalent begomovirus was cotton leaf curl Kokhran virus-Burewala (CLCuKoV-Bu). Unexpectedly, a recently recognized recombinant, cotton leaf curl Multan virus-Rajasthan (CLCuMuV-Ra) was prevalent in five of 15 sites. cotton leaf curl Alabad virus (CLCuAlV) and cotton leaf curl Kokhran virus-Kokhran, 'core' members of CLCuD-begomoviruses that co-occurred with CLCuMuV in the 'Multan' epidemic were detected in one of 15 sentinel plots. Also identified were chickpea chlorotic dwarf virus and 'non-core' CLCuD-begomoviruses, okra enation leaf curl virus, squash leaf curl virus, and tomato leaf curl New Delhi virus. Cotton leaf curl Multan betasatellite (CLCuMuB) was the most prevalent CLCuD-betasatellite, and less commonly, two 'non-core' betasatellites. Recombination analysis revealed previously uncharacterized recombinants among helper virus-betasatellite complexes consisting of CLCuKoV, CLCuMuV, CLCuAlV and CLCuMuB. Population analyses provided early evidence for CLCuMuV-Ra expansion and displacement of CLCuKoV-Bu in India and Pakistan from 2012-2017. Identification of 'core' and non-core CLCuD-species/strains in cotton and other potential reservoirs, and presence of the now predominant CLCuMuV-Ra strain are indicative of ongoing diversification. Investigating the phylodynamics of geminivirus emergence in cotton-vegetable cropping systems offers an opportunity to understand the driving forces underlying disease outbreaks and reconcile viral evolution with epidemiological relationships that also capture pathogen population shifts.


Assuntos
Surtos de Doenças , Paquistão/epidemiologia , Índia
11.
Healthcare (Basel) ; 11(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36900716

RESUMO

Exercise is an integral part of metabolic syndrome (MetS) treatment. Recently, low-volume high-intensity interval training (LOW-HIIT) has emerged as a time-efficient approach to improving cardiometabolic health. Intensity prescriptions for LOW-HIIT are typically based on maximum heart rate (HRmax) percentages. However, HRmax determination requires maximal effort during exercise testing, which may not always be feasible/safe for MetS patients. This trial compared the effects of a 12-week LOW-HIIT program based on: (a) HRmax (HIIT-HR), or (b) submaximal lactate threshold (HIIT-LT), on cardiometabolic health and quality of life (QoL) in MetS patients. Seventy-five patients were randomized to HIIT-HR (5 × 1 min at 80-95% HRmax), HIIT-LT (5 × 1 min at 95-105% LT) groups, both performed twice weekly on cycle ergometers, or a control group (CON). All patients received nutritional weight loss consultation. All groups reduced their body weight (HIIT-HR: -3.9 kg, p < 0.001; HTT-LT: -5.6 kg, p < 0.001; CON: -2.6 kg, p = 0.003). The HIIT-HR and HIIT-LT groups similarly, improved their maximal oxygen uptake (+3.6 and +3.7 mL/kg/min, p < 0.001), glycohemoglobin (-0.2%, p = 0.005, and -0.3%, p < 0.001), homeostasis model assessment index (-1.3 units, p = 0.005, and -1.0 units, p = 0.014), MetS z-score (-1.9 and -2.5 units, p < 0.001) and QoL (+10 points, p = 0.029, and +11 points, p = 0.002), while the CON did not experience changes in these variables. We conclude that HIIT-LT is a viable alternative to HIIT-HR for patients who are not able/willing to undergo maximal exercise testing.

13.
Artigo em Inglês | MEDLINE | ID: mdl-36231609

RESUMO

Initially, we aimed to investigate the impact of a one-year worksite low-volume, high-intensity interval training (LOW-HIIT) on cardiometabolic health in 114 sedentary office workers. Due to the COVID-19 pandemic outbreak, LOW-HIIT was discontinued after 6 months and participants were followed up for 6 months to analyze physical activity/exercise behavior and outcome changes during lockdown. Health examinations, including cardiopulmonary exercise testing and the assessment of cardiometabolic markers were performed baseline (T-1), after 6 months (T-2, termination of worksite LOW-HIIT) and 12 months (T-3, follow-up). Cycle ergometer LOW-HIIT (5 × 1 min at 85-95% HRmax) was performed 2×/week. For follow-up analyses, participants were classified into three groups: HIIT-group (continued home-based LOW-HIIT), EX-group (continued other home-based exercises), and NO-EX-group (discontinued LOW-HIIT/exercise). At T-2, VO2max (+1.5 mL/kg/min, p = 0.002), mean arterial blood pressure (MAB, -4 mmHg, p < 0.001), HbA1c (-0.2%, p = 0.005) and self-reported quality of life (QoL, +5 points, p < 0.001) were improved. At T-3, HIIT-group maintained VO2max and QoL and further improved MAB. EX-group maintained MAB and QoL but experienced a VO2max decrease. In NON-EX, VO2max, MAB and QoL deteriorated. We conclude that LOW-HIIT can be considered a promising option to improve cardiometabolic health in real-life conditions and to mitigate physical inactivity-related negative health impacts during lockdowns.


Assuntos
COVID-19 , Doenças Cardiovasculares , Treinamento Intervalado de Alta Intensidade , COVID-19/epidemiologia , Controle de Doenças Transmissíveis , Humanos , Pandemias/prevenção & controle , Qualidade de Vida , Comportamento Sedentário
14.
Clin Nutr ESPEN ; 51: 222-230, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36184208

RESUMO

BACKGROUND & AIMS: Teduglutide is a Glucagon-like peptide-2 (GLP-2) agonist indicated for the treatment of patients with parenteral support (PS) dependent short bowel syndrome (SBS) with chronic intestinal failure (cIF). Its application is accompanied by a structured nation-wide home-care service program in Germany. We investigated care characteristics and outcome parameters in a clinical real-world observational setting. METHODS: Data generated within a therapy-accompanying home-care service program for adult SBS-cIF patients were analyzed retrospectively for patients treated up to 1 year (data cut: April 2020). RESULTS: In total, 52 teduglutide-treated patients were included by 6 German cIF centers. At teduglutide administration start, 49/52 patients were on PS, 3 of them without macronutrients. The majority of patients received individualized parenteral nutrition (PN) (n = 32/46), while 13/46 were on commercial premixed bags. PS application was done by patients themselves (37%), home-care nurses (19%), relatives (8%) or by a combination of those (16%). In patients with PS dependency at baseline and available follow-up data (n = 40-44), teduglutide treatment resulted in significantly reduced PN days, caloric needs, infusion time, and infusion volume after 6 and 12 months. After 1 year, reduction of infusion time was positively correlated with a reduction of PN calories and volume; 30 patients (68%) were responders (PS-volume reduction ≥20%), and 6 patients (14%) were completely weaned off PS. Sleep disturbances per night were significantly reduced after 3 months of treatment and stool characteristics improved in consistency and significantly in frequency, while meal frequency remained stable. CONCLUSIONS: Teduglutide treatment associated reduction in PS volume and calories was accompanied by reduced infusion days, infusion times, sleep disturbances, stable oral intake surrogates, and improved stool characteristics, all of these potential parameters for improving quality of life. Furthermore, analyzed care characteristics reflect SBS-cIF treatment as a complex, resource-intensive and demanding task for both, healthcare system and patients.


Assuntos
Enteropatias , Insuficiência Intestinal , Síndrome do Intestino Curto , Adulto , Doença Crônica , Fármacos Gastrointestinais/uso terapêutico , Peptídeos Semelhantes ao Glucagon/uso terapêutico , Humanos , Enteropatias/tratamento farmacológico , Peptídeos , Qualidade de Vida , Estudos Retrospectivos , Síndrome do Intestino Curto/tratamento farmacológico
15.
Nutrients ; 14(19)2022 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-36235536

RESUMO

There is ample evidence that specific nutritional strategies can enhance adaptions to resistance and endurance training. However, it is still unclear whether post-session protein supplementation may increase the effects of low-volume high-intensity interval training (LOW-HIIT). We examined the impact of LOW-HIIT combined with protein vs. placebo supplementation on cardiometabolic health indices in sedentary healthy individuals. Forty-seven participants (31.1 ± 8.0 yrs) performed cycle ergometer LOW-HIIT (5−10x1 min at 80−95% maximum heart rate) for eight weeks and randomly received double-blinded 40 g of whey protein (PRO-HIIT, N = 24) or an isocaloric placebo (maltodextrin, PLA-HIIT, N = 23) after each session. The maximum oxygen uptake (VO2max, primary outcome) and several secondary cardiometabolic outcomes were determined pre-/post-intervention. VO2max increased in PRO-HIIT (+2.8 mL/kg/min, p = 0.003) and PLA-HIIT (+3.5 mL/kg/min, p < 0.001). Systolic and diastolic blood pressure decreased in PRO-HIIT (−7/3 mmHg, p < 0.05) and PLA-HIIT (−8/5 mmHg, p < 0.001). Gamma glutamyl transferase (−2 U/L, p = 0.003) decreased in PRO-HIIT and alanine aminotransferase (−3 U/L, p = 0.014) in PLA-HIIT. There were no significant between-group differences in any of the outcome changes. In conclusion, LOW-HIIT improved VO2max and other cardiometabolic markers irrespective of the supplementation condition. Post-session protein supplementation does not seem to provide any additional benefit to LOW-HIIT in improving cardiometabolic health in sedentary healthy individuals.


Assuntos
Doenças Cardiovasculares , Treinamento Intervalado de Alta Intensidade , Adulto , Alanina Transaminase , Suplementos Nutricionais , Humanos , Oxigênio , Consumo de Oxigênio/fisiologia , Poliésteres , Proteínas do Soro do Leite
16.
Phys Rev E ; 106(2-1): 024304, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36109993

RESUMO

Many systems in nature exhibit avalanche dynamics with scale-free features. A general scaling theory has been proposed for critical avalanche profiles in crackling noise, predicting the collapse onto a universal avalanche shape, as well as the scaling behavior of the activity power spectrum as Brown noise. Recently, much attention has been given to the profile of neuronal avalanches, measured in neuronal systems in vitro and in vivo. Although a universal profile was evidenced, confirming the validity of the general scaling theory, the parallel study of the power spectrum scaling under the same conditions was not performed. The puzzling observation is that in the majority of healthy neuronal systems the power spectrum exhibits a behavior close to 1/f, rather than Brown, noise. Here we perform a numerical study of the scaling behavior of the avalanche shape and the power spectrum for a model of integrate and fire neurons with a short-term plasticity parameter able to tune the system to criticality. We confirm that, at criticality, the average avalanche size and the avalanche profile fulfill the general avalanche scaling theory. However, the power spectrum consistently exhibits Brown noise behavior, for both fully excitatory networks and systems with 30% inhibitory networks. Conversely, a behavior closer to 1/f noise is observed in systems slightly off criticality. Results suggest that the power spectrum is a good indicator to determine how close neuronal activity is to criticality.

17.
Microsc Microanal ; : 1-6, 2022 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-36073058

RESUMO

Correlative microscopy approaches are attracting considerable interest in several research fields such as materials and battery research. Recent developments regarding X-ray computer tomography have made this technique available in a compact module for scanning electron microscopes (SEMs). Nano-computed tomography (nanoCT) allows morphological analysis of samples in a nondestructive way and to generate 2D and 3D overviews. However, morphological analysis alone is not sufficient for advanced studies, and to draw conclusions beyond morphology, chemical analysis is needed. While conventional SEM-based chemical analysis techniques such as energy-dispersive X-ray spectroscopy (EDS) are adequate in many cases, they are not well suited for the analysis of trace elements and low-Z elements such as hydrogen or lithium. Furthermore, the large information depth in typical SEM-EDS imaging conditions limits the lateral resolution to micrometer length scales. In contrast, secondary ion mass spectrometry (SIMS) can perform elemental mapping with good surface sensitivity, nanoscale lateral resolution, and the possibility to analyze even low-Z elements and isotopes. In this study, we demonstrate the feasibility and compatibility of a novel FIB-SEM-based correlative nanoCT-SIMS imaging approach to correlate morphological and chemical data of the exact same sample volume, using a cathode material of a commercial lithium battery as an example.

18.
Med Sci Sports Exerc ; 54(11): 1817-1830, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35868017

RESUMO

PURPOSE: High-intensity interval training (HIIT) has been shown to improve cardiorespiratory fitness (CRF) and health-related outcomes in various chronic diseases, including cancer. However, data on feasibility and efficacy of HIIT in advanced cancer patients are still sparse, presumably because of safety concerns, like suspected immunosuppression after vigorous exercise. This randomized, sham-intervention controlled study aimed to investigate feasibility, safety, and preliminary efficacy of very low-volume HIIT (LOW-HIIT) in advanced cancer patients. METHODS: Twenty-seven patients (55.4 ± 13.2 yr) with different advanced cancers (Union for International Cancer Control [UICC] III/IV) were randomly allocated to LOW-HIIT ( n = 13), consisting of 5 × 1 min cycle ergometer intervals (14 min per session total duration) at 80% to 95% HR peak (two sessions per week for 12 wk), or a sham intervention ( n = 14) performing light physical mobilization exercises (SHAM). Primary outcomes were attrition and attendance rates, with values of ≤25% and ≥80%, respectively, considered acceptable. Secondary outcomes were safety, protocol fidelity, physiological (including CRF measures) and patient-reported outcomes (including fatigue and quality of life). RESULTS: One of 13 patients (8%) receiving LOW-HIIT dropped out. Mean attendance rate was ~93%. The prescribed minimum exercise intensity was consistently reached by all patients. Low-volume HIIT was well tolerated and not associated with any serious adverse event nor with increased infection susceptibility. There were no biochemical signs of acute immunosuppression after LOW-HIIT. Contrarily, differentiation and degranulation of natural killer cells was acutely increased postexercise. Low-volume HIIT improved CRF measures including peak oxygen uptake, self-reported fatigue, physical, and social functioning. No significant changes occurred in the SHAM group. CONCLUSIONS: Low-volume HIIT can be regarded as feasible and safe in advanced cancer patients. Our preliminary data indicate favorable acute effects on NK-cells and beneficial chronic adaptations in CRF, fatigue, and aspects of quality of life.


Assuntos
Aptidão Cardiorrespiratória , Terapia por Exercício , Treinamento Intervalado de Alta Intensidade , Neoplasias , Desequilíbrio Hidroeletrolítico , Humanos , Aptidão Cardiorrespiratória/fisiologia , Fadiga/etiologia , Estudos de Viabilidade , Treinamento Intervalado de Alta Intensidade/métodos , Neoplasias/complicações , Neoplasias/terapia , Oxigênio , Qualidade de Vida
19.
Nutrients ; 14(10)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-35631137

RESUMO

Exercise is a cornerstone in metabolic syndrome (MetS) treatment. However, the effects of low-volume exercise modalities on MetS-associated low-grade inflammation are unclear. A total of 106 MetS patients (53.7 ± 11.4 years) were randomized to low-volume high-intensity interval training (LOW-HIIT, 14 min/session), single-set resistance training (1-RT, ~15 min/session), whole-body electromyostimulation (WB-EMS, 20 min/session), three-set resistance training (3-RT, ~50 min/session), each performed 2 ×/week for 12 weeks, or a control group (CON). All groups received nutritional counseling for weight loss. Inflammatory and cardiometabolic indices were analyzed pre- and post-intervention. All groups significantly reduced body weight by an average of 3.6%. Only LOW-HIIT reduced C-reactive protein (CRP) (−1.6 mg/L, p = 0.001) and interleukin-6 (−1.1 pg/mL, p = 0.020). High-sensitivity CRP and lipopolysaccharide-binding protein decreased following LOW-HIIT (−1.4 mg/L, p = 0.001 and −2.1 ng/mL, p = 0.004) and 3-RT (−0.6 mg/L, p = 0.044 and −2.0 ng/mL, p < 0.001). MetS severity score improved with LOW-HIIT (−1.8 units, p < 0.001), 1-RT (−1.6 units, p = 0.005), and 3-RT (−2.3 units, p < 0.001). Despite similar effects on body weight, low-volume exercise modalities have different impact on inflammatory and cardiometabolic outcomes in MetS patients. LOW-HIIT has superior efficacy for improving inflammation compared to 1-RT and WB-EMS. Resistance-based exercise appears to require a higher volume to promote beneficial impact on inflammation.


Assuntos
Doenças Cardiovasculares , Síndrome Metabólica , Treinamento Resistido , Restrição Calórica , Humanos , Inflamação , Síndrome Metabólica/terapia , Obesidade/complicações , Obesidade/terapia
20.
Materials (Basel) ; 15(9)2022 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-35591452

RESUMO

Generating polymer-metal structures by means of additive manufacturing offers huge potential for customized, sustainable and lightweight solutions. However, challenges exist, primarily with regard to reliability and reproducibility of the additively generated joints. In this study, the polymers ABS, PETG and PLA, which are common in material extrusion, were joined to grit-blasted aluminum substrates. Temperature dependence of polymer melt rheology, wetting and tensile single-lap-shear strength were examined in order to obtain appropriate thermal processing conditions. Joints with high adhesive strength in the fresh state were aged for up to 100 days in two different moderate environments. For the given conditions, PETG was most suitable for generating structural joints. Contrary to PETG, ABS-aluminum joints in the fresh state as well as PLA-aluminum joints in the aged state did not meet the demands of a structural joint. For the considered polymers and processing conditions, this study implies that the suitability of a polymer and a thermal processing condition to form a polymer-aluminum joint by material extrusion can be evaluated based on the polymer's rheological properties. Moreover, wetting experiments improved estimation of the resulting tensile single-lap-shear strength.

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