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1.
Braz J Med Biol Res ; 54(5): e10693, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33729393

RESUMEN

The present study compared the effects of a footwear designed to enhance energy return (thermoplastic polyurethane, TPU) vs minimalist shoes on running economy (RE) and endurance performance. In this counterbalanced and crossover design study, 11 recreational male runners performed two submaximal constant-speed running tests and two 3-km time-trials with the two shoe models. Oxygen uptake was measured during submaximal constant-speed running tests in order to determine the RE at 12 km/h and oxygen cost of running (CTO2) at individual average speed sustained during the 3-km running time-trials wearing either of the two shoes. Our results revealed that RE was improved (2.4%) with TPU shoes compared with minimalist shoes (P=0.01). However, there was no significant difference for CTO2 (P=0.61) and running performance (P=0.52) comparing the TPU (710±60 s) and the minimalist (718±63 s) shoe models. These novel findings demonstrate that shoes with enhanced mechanical energy return (i.e. TPU) produced a lower energy cost of running at low (i.e., 12 km/h) but not at high speeds (i.e., average speed sustained during the 3-km running time-trial, ∼15 km/h), ultimately resulting in similar running performance compared to the minimalist shoe.


Asunto(s)
Carrera , Fenómenos Biomecánicos , Estudios Cruzados , Masculino , Consumo de Oxígeno , Zapatos
2.
Anaesthesia ; 76 Suppl 4: 56-62, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33682094

RESUMEN

Anaemia is common, particularly in women and the commonest underlying cause, iron deficiency, is often overlooked. Anaemia is associated with increased morbidity and mortality in patients undergoing anaesthesia; however, women are defined as being anaemic at a lower haemoglobin level than men. In this narrative review, we present the history of iron deficiency anaemia and how women's health has often been overlooked. Iron deficiency was first described as 'chlorosis' and a cause of 'hysteria' in women and initial treatment was by iron filings in cold wine. We present data of population screening demonstrating how common iron deficiency is, affecting 12-18% of apparently 'fit and healthy' women, with the most common cause being heavy menstrual bleeding; both conditions being often unrecognised. We describe a range of symptoms reported by women, that vary from fatigue to brain fog, hair loss and eating ice. We also describe experiments exploring the physical impact of iron deficiency, showing that reduced exercise performance is related to iron deficiency independent of haemoglobin concentration, as well as the impact of iron supplementation in women improving oxygen consumption and fitness. Overall, we demonstrate the need to single out women and investigate iron deficiency rather than accept the dogma of normality and differential treatment; this is to say, the need to change the current standard of care for women undergoing anaesthesia.


Asunto(s)
Anemia Ferropénica/patología , Anemia Ferropénica/complicaciones , Anemia Ferropénica/tratamiento farmacológico , Metabolismo Energético , Fatiga/etiología , Femenino , Hemoglobinas/análisis , Humanos , Hierro/administración & dosificación , Hierro/metabolismo , Consumo de Oxígeno , Rendimiento Físico Funcional
3.
Undersea Hyperb Med ; 48(1): 1-12, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33648028

RESUMEN

The SARS-Cov-2 (COVID-19) pandemic remains a major worldwide public health issue. Initially, improved supportive and anti-inflammatory intervention, often employing known drugs or technologies, provided measurable improvement in management. We have recently seen advances in specific therapeutic interventions and in vaccines. Nevertheless, it will be months before most of the world's population can be vaccinated to achieve herd immunity. In the interim, hyperbaric oxygen (HBO2) treatment offers several potentially beneficial therapeutic effects. Three small published series, one with a propensity-score-matched control group, have demonstrated safety and initial efficacy. Additional anecdotal reports are consistent with these publications. HBO2 delivers oxygen in extreme conditions of hypoxemia and tissue hypoxia, even in the presence of lung pathology. It provides anti-inflammatory and anti-proinflammatory effects likely to ameliorate the overexuberant immune response common to COVID-19. Unlike steroids, it exerts these effects without immune suppression. One study suggests HBO2 may reduce the hypercoagulability seen in COVID patients. Also, hyperbaric oxygen offers a likely successful intervention to address the oxygen debt expected to arise from a prolonged period of hypoxemia and tissue hypoxia. To date, 11 studies designed to investigate the impact of HBO2 on patients infected with SARS-Cov-2 have been posted on clinicaltrials.gov. This paper describes the promising physiologic and biochemical effects of hyperbaric oxygen in COVID-19 and potentially in other disorders with similar pathologic mechanisms.


Asunto(s)
/terapia , Oxigenación Hiperbárica/métodos , /sangre , /inmunología , Hipoxia de la Célula , Síndrome de Liberación de Citoquinas/inmunología , Citocinas/sangre , Humanos , Hipoxia/terapia , Inflamación/terapia , Células Madre Mesenquimatosas , Oxígeno/envenenamiento , Consumo de Oxígeno , Trombofilia/etiología , Trombofilia/terapia
4.
Physiol Rep ; 9(3): e14726, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33523608

RESUMEN

Corona virus disease 2019 (COVID-19) causes symptoms from multiple organs after infection by severe acute respiratory syndrome corona virus 2 (SARS CoV-2). They range from early, low blood oxygen levels (hypoxemia) without breathlessness ("silent hypoxia"), delirium, rashes, and loss of smell (anosmia), to persisting chest pain, muscle weakness and -pain, fatigue, confusion, memory problems and difficulty to concentrate ("brain fog"), mood changes, and unexpected onset of hypertension or diabetes. SARS CoV-2 affects the microcirculation, causing endothelial cell swelling and damage (endotheliitis), microscopic blood clots (microthrombosis), capillary congestion, and damage to pericytes that are integral to capillary integrity and barrier function, tissue repair (angiogenesis), and scar formation. Similar to other instances of critical illness, COVID-19 is also associated with elevated cytokine levels in the systemic circulation. This review examines how capillary damage and inflammation may contribute to these acute and persisting COVID-19 symptoms by interfering with blood and tissue oxygenation and with brain function. Undetectable by current diagnostic methods, capillary flow disturbances limit oxygen diffusion exchange in lungs and tissue and may therefore cause hypoxemia and tissue hypoxia. The review analyzes the combined effects of COVID-19-related capillary damage, pre-existing microvascular changes, and upstream vascular tone on tissue oxygenation in key organs. It identifies a vicious cycle, as infection- and hypoxia-related inflammation cause capillary function to deteriorate, which in turn accelerates hypoxia-related inflammation and tissue damage. Finally, the review addresses the effects of low oxygen and high cytokine levels in brain tissue on neurotransmitter synthesis and mood. Methods to assess capillary functions in human organs and therapeutic means to protect capillary functions and stimulate capillary bed repair may prove important for the individualized management of COVID-19 patients and targeted rehabilitation strategies.


Asunto(s)
/complicaciones , Microvasos/patología , Consumo de Oxígeno , Oxígeno/metabolismo , Animales , /patología , Humanos , Inflamación , Microvasos/metabolismo , Microvasos/virología , Oxígeno/sangre , /patogenicidad
5.
Nat Metab ; 3(2): 196-210, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33619377

RESUMEN

Ketone bodies are generated in the liver and allow for the maintenance of systemic caloric and energy homeostasis during fasting and caloric restriction. It has previously been demonstrated that neonatal ketogenesis is activated independently of starvation. However, the role of ketogenesis during the perinatal period remains unclear. Here, we show that neonatal ketogenesis plays a protective role in mitochondrial function. We generated a mouse model of insufficient ketogenesis by disrupting the rate-limiting hydroxymethylglutaryl-CoA synthase 2 enzyme gene (Hmgcs2). Hmgcs2 knockout (KO) neonates develop microvesicular steatosis within a few days of birth. Electron microscopic analysis and metabolite profiling indicate a restricted energy production capacity and accumulation of acetyl-CoA in Hmgcs2 KO mice. Furthermore, acetylome analysis of Hmgcs2 KO cells revealed enhanced acetylation of mitochondrial proteins. These findings suggest that neonatal ketogenesis protects the energy-producing capacity of mitochondria by preventing the hyperacetylation of mitochondrial proteins.


Asunto(s)
Metabolismo Energético/fisiología , Cuerpos Cetónicos/biosíntesis , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Ácido 3-Hidroxibutírico/metabolismo , Acetilación , Animales , Animales Recién Nacidos , Hidroximetilglutaril-CoA Sintasa/genética , Hidroximetilglutaril-CoA Sintasa/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Ratones Noqueados , Microvasos/fisiología , Consumo de Oxígeno
6.
Nat Commun ; 12(1): 843, 2021 02 16.
Artículo en Inglés | MEDLINE | ID: mdl-33594062

RESUMEN

Adaptive thermogenesis is essential for survival, and therefore is tightly regulated by a central neural circuit. Here, we show that microRNA (miR)-33 in the brain is indispensable for adaptive thermogenesis. Cold stress increases miR-33 levels in the hypothalamus and miR-33-/- mice are unable to maintain body temperature in cold environments due to reduced sympathetic nerve activity and impaired brown adipose tissue (BAT) thermogenesis. Analysis of miR-33f/f dopamine-ß-hydroxylase (DBH)-Cre mice indicates the importance of miR-33 in Dbh-positive cells. Mechanistically, miR-33 deficiency upregulates gamma-aminobutyric acid (GABA)A receptor subunit genes such as Gabrb2 and Gabra4. Knock-down of these genes in Dbh-positive neurons rescues the impaired cold-induced thermogenesis in miR-33f/f DBH-Cre mice. Conversely, increased gene dosage of miR-33 in mice enhances thermogenesis. Thus, miR-33 in the brain contributes to maintenance of BAT thermogenesis and whole-body metabolism via enhanced sympathetic nerve tone through suppressing GABAergic inhibitory neurotransmission. This miR-33-mediated neural mechanism may serve as a physiological adaptive defense mechanism for several stresses including cold stress.


Asunto(s)
MicroARNs/metabolismo , Sistema Nervioso Simpático/fisiología , Termogénesis/genética , Tejido Adiposo Pardo/fisiología , Animales , Temperatura Corporal/fisiología , Peso Corporal , Encéfalo/metabolismo , Línea Celular , Frío , Dieta Alta en Grasa , Estrés del Retículo Endoplásmico , Humanos , Integrasas/metabolismo , Masculino , Ratones , Ratones Obesos , MicroARNs/genética , Consumo de Oxígeno/fisiología , Fenotipo , Subunidades de Proteína/genética , Subunidades de Proteína/metabolismo , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo
7.
Nat Commun ; 12(1): 1209, 2021 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-33619282

RESUMEN

Fructose intake has increased substantially throughout the developed world and is associated with obesity, type 2 diabetes and non-alcoholic fatty liver disease. Currently, our understanding of the metabolic and mechanistic implications for immune cells, such as monocytes and macrophages, exposed to elevated levels of dietary fructose is limited. Here, we show that fructose reprograms cellular metabolic pathways to favour glutaminolysis and oxidative metabolism, which are required to support increased inflammatory cytokine production in both LPS-treated human monocytes and mouse macrophages. A fructose-dependent increase in mTORC1 activity drives translation of pro-inflammatory cytokines in response to LPS. LPS-stimulated monocytes treated with fructose rely heavily on oxidative metabolism and have reduced flexibility in response to both glycolytic and mitochondrial inhibition, suggesting glycolysis and oxidative metabolism are inextricably coupled in these cells. The physiological implications of fructose exposure are demonstrated in a model of LPS-induced systemic inflammation, with mice exposed to fructose having increased levels of circulating IL-1ß after LPS challenge. Taken together, our work underpins a pro-inflammatory role for dietary fructose in LPS-stimulated mononuclear phagocytes which occurs at the expense of metabolic flexibility.


Asunto(s)
Fructosa/farmacología , Glutamina/metabolismo , Inflamación/metabolismo , Inflamación/patología , Lipopolisacáridos/toxicidad , Ácidos/metabolismo , Animales , Ciclo del Ácido Cítrico/efectos de los fármacos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Glucosa/farmacología , Glucólisis/efectos de los fármacos , Marcaje Isotópico , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Análisis de Flujos Metabólicos , Ratones Endogámicos C57BL , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Oxidación-Reducción , Fosforilación Oxidativa/efectos de los fármacos , Consumo de Oxígeno/efectos de los fármacos , Fenotipo , Linfocitos T/efectos de los fármacos , Linfocitos T/metabolismo
8.
Int J Nanomedicine ; 16: 1005-1019, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33603365

RESUMEN

Purpose: Development of hyaluronic acid conjugated metformin-phospholipid sonocomplexes (HA-MPS), a biphasic complexation product compiled for enhancing both the lipophilicity and targeting potential of Metformin (MET) to CD44 receptors on pancreatic cancer. Methods: MET was chemically conjugated to hyaluronic acid (HA) via amide coupling reaction. Then, the HA conjugated MET was physically conjugated to Lipoid™S100 via ultrasound irradiation. A combined D-optimal design was implemented to statistically optimize formulation variables. The HA-MPS were characterized through solubility studies, partition coefficient, drug content uniformity, particle size and zeta potential. The optimized HA-MPS was tested via proton nuclear magnetic resonance, infrared spectroscopy to elucidate the nature of physicochemical interactions in the complex which was further scrutinized on molecular level via molecular docking and dynamic simulation. Results: The solubility and partition studies showed a lipophilicity enhancement up to 67 folds as they adopted inverted micelles configuration based on the packing parameter hypothesis. The optimized HA-MPS showed 11.5 folds lower IC50, extra 25% reduction in oxygen consumption rate, better reduction in hypoxia-inducible factor and reactive oxygen species in MiaPaCa-2 cells. Conclusion: These results proved better internalization of MET which was reflected by abolishing hypoxic tumour microenvironment, a mainstay toward a normoxic and less resistant pancreatic cancer.


Asunto(s)
Ácido Hialurónico/química , Metformina/farmacología , Fosfolípidos/química , Sonicación , Hipoxia Tumoral/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , 1-Octanol/química , Animales , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Glucosa/farmacología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Concentración 50 Inhibidora , Micelas , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Consumo de Oxígeno/efectos de los fármacos , Neoplasias Pancreáticas/patología , Tamaño de la Partícula , Espectroscopía de Protones por Resonancia Magnética , Especies Reactivas de Oxígeno/metabolismo , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Agua/química
9.
JAMA ; 325(6): 542-551, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33560320

RESUMEN

Importance: Endurance exercise is effective in improving peak oxygen consumption (peak V̇o2) in patients with heart failure with preserved ejection fraction (HFpEF). However, it remains unknown whether differing modes of exercise have different effects. Objective: To determine whether high-intensity interval training, moderate continuous training, and guideline-based advice on physical activity have different effects on change in peak V̇o2 in patients with HFpEF. Design, Setting, and Participants: Randomized clinical trial at 5 sites (Berlin, Leipzig, and Munich, Germany; Antwerp, Belgium; and Trondheim, Norway) from July 2014 to September 2018. From 532 screened patients, 180 sedentary patients with chronic, stable HFpEF were enrolled. Outcomes were analyzed by core laboratories blinded to treatment groups; however, the patients and staff conducting the evaluations were not blinded. Interventions: Patients were randomly assigned (1:1:1; n = 60 per group) to high-intensity interval training (3 × 38 minutes/week), moderate continuous training (5 × 40 minutes/week), or guideline control (1-time advice on physical activity according to guidelines) for 12 months (3 months in clinic followed by 9 months telemedically supervised home-based exercise). Main Outcomes and Measures: Primary end point was change in peak V̇o2 after 3 months, with the minimal clinically important difference set at 2.5 mL/kg/min. Secondary end points included changes in metrics of cardiorespiratory fitness, diastolic function, and natriuretic peptides after 3 and 12 months. Results: Among 180 patients who were randomized (mean age, 70 years; 120 women [67%]), 166 (92%) and 154 (86%) completed evaluation at 3 and 12 months, respectively. Change in peak V̇o2 over 3 months for high-intensity interval training vs guideline control was 1.1 vs -0.6 mL/kg/min (difference, 1.5 [95% CI, 0.4 to 2.7]); for moderate continuous training vs guideline control, 1.6 vs -0.6 mL/kg/min (difference, 2.0 [95% CI, 0.9 to 3.1]); and for high-intensity interval training vs moderate continuous training, 1.1 vs 1.6 mL/kg/min (difference, -0.4 [95% CI, -1.4 to 0.6]). No comparisons were statistically significant after 12 months. There were no significant changes in diastolic function or natriuretic peptides. Acute coronary syndrome was recorded in 4 high-intensity interval training patients (7%), 3 moderate continuous training patients (5%), and 5 guideline control patients (8%). Conclusions and Relevance: Among patients with HFpEF, there was no statistically significant difference in change in peak V̇o2 at 3 months between those assigned to high-intensity interval vs moderate continuous training, and neither group met the prespecified minimal clinically important difference compared with the guideline control. These findings do not support either high-intensity interval training or moderate continuous training compared with guideline-based physical activity for patients with HFpEF. Trial Registration: ClinicalTrials.gov Identifier: NCT02078947.


Asunto(s)
Terapia por Ejercicio/métodos , Ejercicio Físico , Insuficiencia Cardíaca/metabolismo , Entrenamiento de Intervalos de Alta Intensidad , Consumo de Oxígeno , Anciano , Medicina Basada en la Evidencia , Tolerancia al Ejercicio , Femenino , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Guías de Práctica Clínica como Asunto , Volumen Sistólico
12.
Respir Med ; 179: 106312, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33636568

RESUMEN

INTRODUCTION: Efforts to meet increased oxygen demands in COVID-19 patients are a priority in averting mechanical ventilation (MV), associated with high mortality approaching 76.4-97.2%. Novel methods of oxygen delivery could mitigate that risk. Oxygen hoods/helmets may improve: O2-saturation (SaO2), reduce in-hospital mechanical ventilation and mortality rates, and reduce length of hospitalization in hypoxic Covid-19 patients failing on conventional high-flow oxygen delivery systems. METHODS: DesignProspective Controlled Cohort Study. SettingSingle Center. ParticipantsAll patients admitted with a diagnosis of COVID-19 were reviewed and 136/347 patients met inclusion criteria. Study period3/6/2020 to 5/1/2020. 136 participants completed the study with known status for all outcome measures. Intervention or exposureOxygen hoods/helmets as compared to conventional high-flow oxygen delivery systems. MAIN OUTCOME(S) AND MEASURE(S): 1) Pre and post change in oxygen saturation (SaO2). 2) In-hospital Mechanical Ventilation (MV). 3) In-hospital Mortality. 4) Length of hospitalization. RESULTS: 136 patients including 58-intervention and 78-control patients were studied. Age, gender, and other demographics/prognostic indicators were comparable between cohorts. Oxygen hoods averted imminent or immediate intubation/MV in all 58 COVID-19 patients failing on conventional high-flow oxygen delivery systems with a mean improvement in SaO2 of 8.8%, p < 0.001. MV rates were observed to be higher in the control 37/78 (47.4%) as compared to the intervention cohort 23/58 (39.7%), a difference of 7.7%, a 27% risk reduction, not statistically significant, OR 95%CI 0.73 (0.37-1.5). Mortality rates were observed higher in the control 54/78 (69.2%) as compared to the intervention cohort 36/58 (62.1%), a difference of 7.1%, a 27% risk reduction, not statistically significant OR 95%CI 0.73 (0.36-1.5). CONCLUSION: Oxygen hoods demonstrate improvement in SaO2 for patients failing on conventional high-flow oxygen-delivery systems and prevented imminent mechanical ventilation. In-hospital mechanical ventilation and mortality rates were reduced with the use of oxygen hoods but not found to be statistically significant. The oxygen hood is a safe, effective oxygen-delivery system which may reduce intubation/MV and mortality rates. Their use should be considered in treating hypoxic COVID-19 patients. Further research is warranted. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04407260.


Asunto(s)
/complicaciones , Hipoxia/terapia , Consumo de Oxígeno/fisiología , Terapia por Inhalación de Oxígeno/instrumentación , Respiración Artificial/instrumentación , Adulto , Anciano , Anciano de 80 o más Años , Falla de Equipo , Femenino , Humanos , Hipoxia/etiología , Hipoxia/mortalidad , Masculino , Persona de Mediana Edad , Pandemias , Pronóstico , Estudios Prospectivos , Tasa de Supervivencia/tendencias , Insuficiencia del Tratamiento , Estados Unidos/epidemiología
13.
Medicine (Baltimore) ; 100(5): e23971, 2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33592851

RESUMEN

BACKGROUND: The purpose of this study is to explore the association between extravascular lung water (EVLW) and prognosis of sepsis (PS). METHODS: We will carry out comprehensive literature search in electronic databases (PUBMED/MEDLINE, EMBASE, CENTRAL, WorldSciNet, PsycINFO, Allied and Complementary Medicine Database, CBM, and CNKI) and additional sources. All electronic databases will be searched from their initial to the present without language restrictions. Case-controlled studies reporting the association between EVLW and PS will be evaluated for inclusion. Outcomes of interest will include mortality rate, extravascular lung water index, pulmonary vascular permeability index, blood lactate clearance, oxygenation index, blood gas analysis, PaO2/FiO2, cardiac output index, global end diastolic volume index, intrathoracic blood volume index, systemic resistance index, acute physiology and chronic health scoring system II, and infection-related organ failure scoring system. Study quality will be evaluated using Newcastle-Ottawa Tool, and statistical analysis will be performed utilizing RevMan 5.4 software. RESULTS: This study will summarize the most recent evidence to investigate the association between EVLW and PS. CONCLUSIONS: The results of this study will provide an exhaustive view of the association between EVLW and PS. STUDY REGISTRATION OSF: osf.io/vhnxw.


Asunto(s)
Agua Pulmonar Extravascular/metabolismo , Sepsis/mortalidad , Sepsis/fisiopatología , APACHE , Análisis de los Gases de la Sangre , Presión Sanguínea , Permeabilidad Capilar , Gasto Cardíaco , Estudios de Casos y Controles , Humanos , Ácido Láctico/sangre , Puntuaciones en la Disfunción de Órganos , Consumo de Oxígeno , Pronóstico , Circulación Pulmonar , Proyectos de Investigación , Medición de Riesgo , Factores de Riesgo , Revisiones Sistemáticas como Asunto
14.
Pediatr Cardiol ; 42(3): 554-559, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33394120

RESUMEN

The COVID-19 pandemic has had devastating direct consequences on the health of affected patients. It has also had a significant impact on the ability of unaffected children to be physically active. We evaluated the effect of deconditioning from social distancing and school shutdowns implemented during the COVID-19 pandemic on the cardiovascular fitness of healthy unaffected children. This is a single-center, retrospective case-control study performed in an urban tertiary referral center. A cohort of 10 healthy children that underwent cardiopulmonary exercise testing after COVID-19 hospital restrictions were lifted was compared to a matched cohort before COVID-19-related shutdowns on school and after-school activities. Comparisons of oxygen uptake (VO2) max and VO2 at anaerobic threshold between the pre- and post-COVID-19 cohorts were done. The VO2 max in the post-COVID cohort was significantly lower than in the pre-COVID cohort (39.1 vs. 44.7, p = 0.031). Only one out of ten patients had a higher VO2 max when compared to their matched pre-COVID control and was also the only patient with a documented history of participation in varsity-type athletics. The percentile of predicted VO2 was significantly lower in the post-COVID cohort (95% vs. 105%, p = 0.042). This study for the first time documented a significant measurable decline in physical fitness of healthy children as a result of the COVID-19 pandemic and its associated restrictions. Measures need to be identified that encourage and facilitate regular exercise in children in a way that are not solely dependent on school and organized after-school activities.


Asunto(s)
/epidemiología , Ejercicio Físico/fisiología , Estado de Salud , Consumo de Oxígeno/fisiología , Pandemias , Aptitud Física/fisiología , Instituciones Académicas , Adolescente , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Masculino , New York/epidemiología , Estudios Retrospectivos
15.
Sensors (Basel) ; 21(2)2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-33467511

RESUMEN

Wearable technology has allowed for the real-time assessment of mechanical work employed in several sporting activities. Through novel power metrics, Functional Threshold Power have shown a reliable indicator of training intensities. This study aims to determine the relationship between mean power output (MPO) values obtained during three submaximal running time trials (i.e., 10 min, 20 min, and 30 min) and the functional threshold power (FTP). Twenty-two recreationally trained male endurance runners completed four submaximal running time trials of 10, 20, 30, and 60 min, trying to cover the longest possible distance on a motorized treadmill. Absolute MPO (W), normalized MPO (W/kg) and standard deviation (SD) were calculated for each time trial with a power meter device attached to the shoelaces. All simplified FTP trials analyzed (i.e., FTP10, FTP20, and FTP30) showed a significant association with the calculated FTP (p < 0.001) for both MPO and normalized MPO, whereas stronger correlations were found with longer time trials. Individual correction factors (ICF% = FTP60/FTPn) of ~90% for FTP10, ~94% for FTP20, and ~96% for FTP30 were obtained. The present study procures important practical applications for coaches and athletes as it provides a more accurate estimation of FTP in endurance running through less fatiguing, reproducible tests.


Asunto(s)
Carrera , Dispositivos Electrónicos Vestibles , Animales , Atletas , Prueba de Esfuerzo , Fatiga , Humanos , Masculino , Consumo de Oxígeno , Resistencia Física
16.
Methods Mol Biol ; 2216: 57-73, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33475994

RESUMEN

Renal tissue hypoperfusion and hypoxia are early key elements in the pathophysiology of acute kidney injury of various origins, and may also promote progression from acute injury to chronic kidney disease. Here we describe test interventions that are used to study the control of renal hemodynamics and oxygenation in experimental animals in the context of kidney-specific control of hemodynamics and oxygenation. The rationale behind the use of the individual tests, the physiological responses of renal hemodynamics and oxygenation, the use in preclinical studies, and the possible application in humans are discussed.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers.


Asunto(s)
Biomarcadores/análisis , Procesamiento de Imagen Asistido por Computador/métodos , Riñón/fisiopatología , Imagen por Resonancia Magnética/métodos , Monitoreo Fisiológico/métodos , Oxígeno/metabolismo , Circulación Renal , Animales , Progresión de la Enfermedad , Hemodinámica , Humanos , Ratones , Consumo de Oxígeno , Ratas , Programas Informáticos
17.
Methods Mol Biol ; 2216: 89-107, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33475996

RESUMEN

Renal tissue hypoperfusion and hypoxia are early key elements in the pathophysiology of acute kidney injury of various origins, and may also promote progression from acute injury to chronic kidney disease. Here we describe basic principles of methodology to quantify renal hemodynamics and tissue oxygenation by means of invasive probes in experimental animals. Advantages and disadvantages of the various methods are discussed in the context of the heterogeneity of renal tissue perfusion and oxygenation.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by a separate chapter describing the experimental procedure and data analysis.


Asunto(s)
Biomarcadores/análisis , Hemodinámica , Riñón/fisiología , Monitoreo Fisiológico/métodos , Oxígeno/análisis , Circulación Renal , Animales , Electrodos , Rayos Láser , Consumo de Oxígeno , Perfusión , Programas Informáticos
18.
Methods Mol Biol ; 2216: 171-185, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33476000

RESUMEN

The role of hypoxia in renal disease and injury has long been suggested but much work still remains, especially as it relates to human translation. Invasive pO2 probes are feasible in animal models but not for human use. In addition, they only provide localized measurements. Histological methods can identify hypoxic tissue and provide a spatial distribution, but are invasive and allow only one-time point. Blood oxygenation level dependent (BOLD) MRI is a noninvasive method that can monitor relative oxygen availability across the kidney. It is based on the inherent differences in magnetic properties of oxygenated vs. deoxygenated hemoglobin. Presence of deoxyhemoglobin enhances the spin-spin relaxation rate measured using a gradient echo sequence, known as R2* (= 1/T2*). While the key interest of BOLD MRI is in the application to humans, use in preclinical models is necessary primarily to validate the measurement against invasive methods, to better understand physiology and pathophysiology, and to evaluate novel interventions. Application of MRI acquisitions in preclinical settings involves several challenges both in terms of logistics and data acquisition. This section will introduce the concept of BOLD MRI and provide some illustrative applications. The following sections will discuss the technical issues associated with data acquisition and analysis.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.


Asunto(s)
Biomarcadores/análisis , Procesamiento de Imagen Asistido por Computador/métodos , Riñón/fisiología , Imagen por Resonancia Magnética/métodos , Monitoreo Fisiológico/métodos , Consumo de Oxígeno , Oxígeno/sangre , Animales , Análisis de los Gases de la Sangre , Humanos , Programas Informáticos
19.
Methods Mol Biol ; 2216: 327-347, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33476009

RESUMEN

Renal tissue hypoperfusion and hypoxia are early key elements in the pathophysiology of acute kidney injury of various origins, and may also promote progression from acute injury to chronic kidney disease. Here we describe methods to study control of renal hemodynamics and tissue oxygenation by means of invasive probes in anesthetized rats. Step-by-step protocols are provided for two setups, one for experiments in laboratories for integrative physiology and the other for experiments within small-animal magnetic resonance scanners.This publication is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by a separate chapter describing the basic concepts of quantitatively assessing renal perfusion and oxygenation with invasive probes.


Asunto(s)
Hemodinámica , Procesamiento de Imagen Asistido por Computador/métodos , Riñón/fisiología , Imagen por Resonancia Magnética/métodos , Monitoreo Fisiológico/métodos , Oxígeno/metabolismo , Animales , Riñón/cirugía , Masculino , Consumo de Oxígeno , Ratas , Ratas Wistar , Programas Informáticos
20.
Methods Mol Biol ; 2216: 403-417, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33476013

RESUMEN

Renal hypoxia is generally accepted as a key pathophysiologic event in acute kidney injury of various origins, and has also been suggested to play a role in the development of chronic kidney disease. Here we describe a step-by-step experimental protocol for indirect monitoring of renal blood oxygenation in rodents via the deoxyhemoglobin sensitive MR parameters T2* and T2-a contrast mechanism known as the blood oxygenation level dependent (BOLD) effect. Since an absolute quantification of renal oxygenation from T2*/T2 remains challenging, the effects of controlled and standardized variations in the fraction of inspired oxygen are used for bench marking. This MRI method may be useful for investigating renal blood oxygenation of small rodents in vivo under various experimental (patho)physiological conditions.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by two separate chapters describing the basic concept and data analysis.


Asunto(s)
Procesamiento de Imagen Asistido por Computador/métodos , Riñón/fisiología , Imagen por Resonancia Magnética/métodos , Monitoreo Fisiológico/métodos , Oxígeno/sangre , Animales , Consumo de Oxígeno , Ratas , Ratas Endogámicas Lew , Ratas Sprague-Dawley , Ratas Wistar , Programas Informáticos
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