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BACKGROUND: The consumption of high-caloric diets strongly contributes to the development of non-communicable diseases (NCDs), including cardiovascular disease, the leading cause of mortality worldwide. Exercise (along with diet intervention) is one of the primary non-pharmacological approaches to promote a healthier lifestyle and counteract the rampant prevalence of NCDs. The present study evaluated the effects of exercise cessation after a short period training on the cardiac metabolic and mitochondrial function of female rats. METHODS: Seven-week-old female Sprague-Dawley rats were fed a control or a high-fat, high-sugar (HFHS) diet and, after 7 weeks, the animals were kept on a sedentary lifestyle or submitted to endurance exercise for 3 weeks (6 days per week, 20-60 min/day). The cardiac samples were analysed 8 weeks after exercise cessation. RESULTS: The consumption of the HFHS diet triggered impaired glucose tolerance, whereas the HFHS diet and physical exercise resulted in different responses in plasma adiponectin and leptin levels. Cardiac mitochondrial respiration efficiency was decreased by the HFHS diet consumption, which led to reduced ATP and increased NAD(P)H mitochondrial levels, which remained prevented by exercise 8 weeks after cessation. Exercise training-induced cardiac adaptations in redox balance, namely increased relative expression of Nrf2 and downstream antioxidant enzymes persist after an eight-week exercise cessation period. CONCLUSIONS: Endurance exercise modulated cardiac redox balance and mitochondrial efficiency in female rats fed a HFHS diet. These findings suggest that exercise may elicit cardiac adaptations crucial for its role as a non-pharmacological intervention for individuals at risk of developing NCDs.
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BACKGROUND: To determine the percentage of patients who have silicone droplets in the vitreous after treatment with different anti-Vascular Endothelial Growth Factor (anti-VEGF) intravitreal injections (IVI) and how symptomatic they are. METHODS: One hundred fifty-two eyes of 140 patients who had at least received an IVI were recruited for this study. Data collection included the number and type of IVI (aflibercept, ranibizumab and bevacizumab) and the follow-up time. A complete ophthalmologic examination was carried out and patients were classified in four groups according to the amount of silicone droplets found in dilated fundoscopy (nonexistent, scarce, moderate and abundant). Measurement of intraocular pressure (IOP) was also carried out. An interview was conducted to report the presence and intensity of the symptomatology. RESULTS: Silicone oil droplets were reported in 109 eyes (71.7%). A positive correlation was found between the number of IVIs received and the quantity of droplets found, especially when aflibercept was used. Posterior vitreous detachment (PVD) was present in 65.8% of the patients, showing a positive correlation with the number of bubbles. Regarding the symptomatology, 60 eyes (39.5%) had floaters and the disturbance was reported to be 4 out of 10. The group with a moderate amount of silicone droplets had the highest percentage of floaters (60%). No statistical differences in the IOP were found between groups, although the group with abundant droplets had a higher mean IOP. CONCLUSION: A high prevalence of silicone droplets in vitreous of patients who undergo IVI treatment was found. It appears to have little impact on symptomatology and rise of IOP.
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Glaucoma , Óleos de Silicone , Inibidores da Angiogênese/uso terapêutico , Bevacizumab , Glaucoma/tratamento farmacológico , Humanos , Pressão Intraocular , Injeções Intravítreas , Prevalência , Ranibizumab , Silicones , Fator A de Crescimento do Endotélio VascularRESUMO
AIMS/HYPOTHESIS: Increased levels of branched-chain amino acids (BCAAs) are associated with type 2 diabetes pathogenesis. However, most metabolomic studies are limited to an analysis of plasma metabolites under fasting conditions, rather than the dynamic shift in response to a metabolic challenge. Moreover, metabolomic profiles of peripheral tissues involved in glucose homeostasis are scarce and the transcriptomic regulation of genes involved in BCAA catabolism is partially unknown. This study aimed to identify differences in circulating and skeletal muscle BCAA levels in response to an OGTT in individuals with normal glucose tolerance (NGT) or type 2 diabetes. Additionally, transcription factors involved in the regulation of the BCAA gene set were identified. METHODS: Plasma and vastus lateralis muscle biopsies were obtained from individuals with NGT or type 2 diabetes before and after an OGTT. Plasma and quadriceps muscles were harvested from skeletal muscle-specific Ppargc1a knockout and transgenic mice. BCAA-related metabolites and genes were assessed by LC-MS/MS and quantitative RT-PCR, respectively. Small interfering RNA and adenovirus-mediated overexpression techniques were used in primary human skeletal muscle cells to study the role of PPARGC1A and ESRRA in the expression of the BCAA gene set. Radiolabelled leucine was used to analyse the impact of oestrogen-related receptor α (ERRα) knockdown on leucine oxidation. RESULTS: Impairments in BCAA catabolism in people with type 2 diabetes under fasting conditions were exacerbated after a glucose load. Branched-chain keto acids were reduced 37-56% after an OGTT in the NGT group, whereas no changes were detected in individuals with type 2 diabetes. These changes were concomitant with a stronger correlation with glucose homeostasis biomarkers and downregulated expression of branched-chain amino acid transaminase 2, branched-chain keto acid dehydrogenase complex subunits and 69% of downstream BCAA-related genes in skeletal muscle. In primary human myotubes overexpressing peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α, encoded by PPARGC1A), 61% of the analysed BCAA genes were upregulated, while 67% were downregulated in the quadriceps of skeletal muscle-specific Ppargc1a knockout mice. ESRRA (encoding ERRα) silencing completely abrogated the PGC-1α-induced upregulation of BCAA-related genes in primary human myotubes. CONCLUSIONS/INTERPRETATION: Metabolic inflexibility in type 2 diabetes impacts BCAA homeostasis and attenuates the decrease in circulating and skeletal muscle BCAA-related metabolites after a glucose challenge. Transcriptional regulation of BCAA genes in primary human myotubes via PGC-1α is ERRα-dependent.
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Diabetes Mellitus Tipo 2 , Aminoácidos de Cadeia Ramificada/metabolismo , Animais , Cromatografia Líquida , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Humanos , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptores de Estrogênio , Espectrometria de Massas em Tandem , Receptor ERRalfa Relacionado ao EstrogênioRESUMO
Optical amplifiers in all ranges of the electromagnetic spectrum exhibit an essential characteristic, namely the input signal during the propagation in the amplifier medium is multiplied by the avalanche effect of the stimulated emission to produce exponential growth. We perform a theoretical study motivated and supported by experimental data on a He gas amplifier driven by intense 30-fs-long laser pulses and seeded with attosecond pulse trains generated in a separated Ne gas jet. We demonstrate that the strong-field theory in the frame of high harmonic generation fully supports the appearance of the avalanche effect in the amplification of extreme ultraviolet attosecond pulse trains. We theoretically separate and identify different physical processes taking part in the interaction and we demonstrate that X-ray parametric amplification dominates over others. In particular, we identify strong-field mediated intrapulse X-ray parametric processes as decisive for amplification at the single-atom level. We confirm that the amplification takes place at photon energies where the amplifier is seeded and when the seed pulses are perfectly synchronized with the driving strong field in the amplifier. Furthermore, propagation effects, phase matching and seed synchronization can be exploited to tune the amplified spectral range within the seed bandwidth.
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BACKGROUND: The adult skeletal muscle is a plastic tissue with a remarkable ability to adapt to different levels of activity by altering its excitability, its contractile and metabolic phenotype and its mass. We previously reported on the potential of adult zebrafish as a tractable experimental model for exercise physiology, established its optimal swimming speed and showed that swimming-induced contractile activity potentiated somatic growth. Given that the underlying exercise-induced transcriptional mechanisms regulating muscle mass in vertebrates are not fully understood, here we investigated the cellular and molecular adaptive mechanisms taking place in fast skeletal muscle of adult zebrafish in response to swimming. RESULTS: Fish were trained at low swimming speed (0.1 m/s; non-exercised) or at their optimal swimming speed (0.4 m/s; exercised). A significant increase in fibre cross-sectional area (1.290±88 vs. 1.665±106 µm2) and vascularization (298±23 vs. 458±38 capillaries/mm2) was found in exercised over non-exercised fish. Gene expression profiling by microarray analysis evidenced the activation of a series of complex transcriptional networks of extracellular and intracellular signaling molecules and pathways involved in the regulation of muscle mass (e.g. IGF-1/PI3K/mTOR, BMP, MSTN), myogenesis and satellite cell activation (e.g. PAX3, FGF, Notch, Wnt, MEF2, Hh, EphrinB2) and angiogenesis (e.g. VEGF, HIF, Notch, EphrinB2, KLF2), some of which had not been previously associated with exercise-induced contractile activity. CONCLUSIONS: The results from the present study show that exercise-induced contractile activity in adult zebrafish promotes a coordinated adaptive response in fast muscle that leads to increased muscle mass by hypertrophy and increased vascularization by angiogenesis. We propose that these phenotypic adaptations are the result of extensive transcriptional changes induced by exercise. Analysis of the transcriptional networks that are activated in response to exercise in the adult zebrafish fast muscle resulted in the identification of key signaling pathways and factors for the regulation of skeletal muscle mass, myogenesis and angiogenesis that have been remarkably conserved during evolution from fish to mammals. These results further support the validity of the adult zebrafish as an exercise model to decipher the complex molecular and cellular mechanisms governing skeletal muscle mass and function in vertebrates.
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Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Neovascularização Fisiológica/genética , Condicionamento Físico Animal , Ativação Transcricional , Animais , Biologia Computacional , Perfilação da Expressão Gênica , Anotação de Sequência Molecular , Contração Muscular/genética , Transcriptoma , Peixe-ZebraRESUMO
BACKGROUND: Several strategies have been developed to counteract liver injury as a consequence of nonsteroid anti-inflammatory drugs toxicity. Here, we aimed to determine whether physical exercise results in liver mitochondrial protection against in vitro diclofenac toxicity. MATERIAL AND METHODS: Male adult Sprague-Dawley rats were divided into sedentary, 12-week endurance training (ET) and voluntary activity (VPA). In vitro liver mitochondrial function as assessed by oxygen consumption, transmembrane electric potential (ΔΨ) and susceptibility to the mitochondrial permeability transition pore (MPTP) was evaluated in the absence and presence of diclofenac. Mitochondrial oxidative stress markers [MnSOD, aconitase, -SH and MDA, SIRT3, p66shc(Ser36)/p66shc ratio] and apoptotic signalling (caspases 3, 8 and 9, Bax, Bcl-2 and CypD) were assessed. Content of OXPHOS components and qualitative liver morphological evaluation were assessed. RESULTS: Despite no effects of ET and VPA on basal liver mitochondrial oxygen consumption or ΔΨ endpoints, exercised animals showed lower susceptibility to MPTP. Diclofenac-induced decrease in ΔΨ, increased state 4 respiration and susceptibility to MPTP opening were all prevented by exercise. Under untreated conditions, VPA group showed higher aconitase activity, while ET decreased MDA and increased Bax content. VPA decreased p66shc(Ser36), complex III and V OXPHOS subunits. Both ET and VPA increased complex IV OXPHOS subunit, and SIRT3 and Bcl-2 content and decreased caspase 9 activity. Unexpectedly, ET and VPA decreased ANT. CONCLUSIONS: Both chronic physical exercise models augmented the resistance to in vitro diclofenac-induced mitochondrial alterations, including increased MPTP susceptibility, possibly by modulating oxidative stress and MPTP regulators.
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Anti-Inflamatórios não Esteroides/toxicidade , Diclofenaco/toxicidade , Mitocôndrias Hepáticas/fisiologia , Doenças Mitocondriais/prevenção & controle , Condicionamento Físico Animal/fisiologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Biomarcadores/metabolismo , Masculino , Potenciais da Membrana/fisiologia , Microscopia Eletrônica de Transmissão , Mitocôndrias Hepáticas/efeitos dos fármacos , Doenças Mitocondriais/induzido quimicamente , Doenças Mitocondriais/fisiopatologia , Neurotoxinas/farmacologia , Estresse Oxidativo/fisiologia , Consumo de Oxigênio/fisiologia , Ratos Sprague-Dawley , RespiraçãoRESUMO
PURPOSE: Uveitis can lead to secondary glaucoma, a condition with challenging management that can carry irreversible visual loss. Filtering surgery has demonstrated a higher failure rate, increased incidence of postoperative complications and reinterventions in uveitic patients. There is no consensus on the optimal surgical approach for uveitic glaucoma (UG) due to limited data comparing various intraocular pressure (IOP)-lowering surgeries. This retrospective cohort aims to assess the clinical outcomes of trabeculectomy (TBT), non-penetrating deep sclerectomy (NPDS), Ex-PRESS shunt and Ahmed glaucoma valve, providing additional insights into the long-term IOP control and safety of filtering surgeries in UG. METHODS: The filtering surgery was performed on 32 eyes of 27 UG patients. Complete success was defined as IOP ≤ 18 mmHg or a 30% reduction. Qualified success allowed topical hypotensive treatment. RESULTS: Complete success was 40.63% (13/32) at 12 months and 36.67% (11/30) at 36 months. Qualified success was 84.38% (27/32) at 12 months and 63.33% (19/30) at 36 months. In the survival analysis, both NPDS and Ex-PRESS demonstrated decreased failure rates compared to TBT (NPDS vs TBT: HR = 0.20, p = 0.049; Ex-PRESS vs TBT: HR = 0.28, p = 0.13). One or more reinterventions were required in 34.38% (11/32) of the eyes. NPDS had the lowest incidence of hypotony. Secondary cataract was a common complication in all groups. CONCLUSION: Various filtering surgeries are safe and effective procedures for lowering IOP and reducing the requirement of topical antihypertensives in UG at 36 months. However, one-third of the patients will require another IOP-lowering procedure.
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Implantes para Drenagem de Glaucoma , Glaucoma , Pressão Intraocular , Esclerostomia , Trabeculectomia , Uveíte , Acuidade Visual , Humanos , Feminino , Masculino , Estudos Retrospectivos , Pressão Intraocular/fisiologia , Seguimentos , Adulto , Pessoa de Meia-Idade , Uveíte/cirurgia , Uveíte/complicações , Uveíte/fisiopatologia , Trabeculectomia/métodos , Esclerostomia/métodos , Glaucoma/cirurgia , Glaucoma/fisiopatologia , Acuidade Visual/fisiologia , Resultado do Tratamento , Idoso , Adulto Jovem , Adolescente , Fatores de Tempo , Tonometria OcularRESUMO
Increased plasma creatine concentrations are associated with the risk of type 2 diabetes, but whether this alteration is associated with or causal for impairments in metabolism remains unexplored. Because skeletal muscle is the main disposal site of both creatine and glucose, we investigated the role of intramuscular creatine metabolism in the pathophysiology of insulin resistance in type 2 diabetes. In men with type 2 diabetes, plasma creatine concentrations were increased, and intramuscular phosphocreatine content was reduced. These alterations were coupled to reduced expression of sarcomeric mitochondrial creatine kinase 2 (CKMT2). In C57BL/6 mice fed a high-fat diet, neither supplementation with creatine for 2 weeks nor treatment with the creatine analog ß-GPA for 1 week induced changes in glucose tolerance, suggesting that increased circulating creatine was associated with insulin resistance rather than causing it. In C2C12 myotubes, silencing Ckmt2 using small interfering RNA reduced mitochondrial respiration, membrane potential, and glucose oxidation. Electroporation-mediated overexpression of Ckmt2 in skeletal muscle of high-fat diet-fed male mice increased mitochondrial respiration, independent of creatine availability. Given that overexpression of Ckmt2 improved mitochondrial function, we explored whether exercise regulates CKMT2 expression. Analysis of public data revealed that CKMT2 content was up-regulated by exercise training in both humans and mice. We reveal a previously underappreciated role of CKMT2 in mitochondrial homeostasis beyond its function for creatine phosphorylation, independent of insulin action. Collectively, our data provide functional evidence for how CKMT2 mediates mitochondrial dysfunction associated with type 2 diabetes.
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Creatina Quinase Mitocondrial , Diabetes Mellitus Tipo 2 , Insulina , Músculo Esquelético , Animais , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Creatina/metabolismo , Creatina Quinase Mitocondrial/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Dieta Hiperlipídica , Glucose/metabolismo , Insulina/metabolismo , Resistência à Insulina , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismoRESUMO
Pregnancy may be a challenging period for the maternal systems and has been regarded as a stress test, as imperceptible/mild dysfunctions eventually present may be exacerbated during this period. The cardiovascular system is no exception, and several morphological and functional adaptations accompanying pregnancy have been described. However, long-term pregnancy-induced cardiac molecular alterations remain highly unexplored. The postpartum is marked by reverse remodeling of the pregnancy-induced cardiovascular adaptations, representing a possible critical period for assessing future maternal cardiovascular health. The current study explored the molecular and metabolic alterations in the cardiac tissue eight weeks after a physiological uncomplicated pregnancy. Female Sprague-Dawley rats were fed a chow diet through pregnancy, lactation, and weaning and compared to their non-pregnant counterparts. Eight weeks postpartum, increased levels of the phosphorylated form of AMPKα (Thr172) and its ratio to total AMPKα indicated possible alterations in cardiac metabolic flexibility, accompanied by increased Pparα and Hif1α transcripts levels. Additionally, postpartum hearts exhibited higher mitochondrial ATP and NADH levels without major changes in mitochondrial respiratory function. Elevated Nrf2 levels in the cardiac tissue suggested potential implications for cardiac redox balance, further supported by increased levels or activity of proteins directly regulated by Nrf2. The findings herein reported suggest that at eight weeks postpartum, molecular alterations induced by pregnancy, especially regarding redox balance, are still observed in the mothers' heart. These alterations present at late postpartum may open new avenues to understand the different risk for cardiovascular complications development after normal pregnancies.
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BACKGROUND: The maintenance of skeletal muscle plasticity upon changes in the environment, nutrient supply, and exercise depends on regulatory mechanisms that couple structural and metabolic adaptations. The mechanisms that interconnect both processes at the transcriptional level remain underexplored. Nr2f6, a nuclear receptor, regulates metabolism and cell differentiation in peripheral tissues. However, its role in the skeletal muscle is still elusive. Here, we aimed to investigate the effects of Nr2f6 modulation on muscle biology in vivo and in vitro. METHODS: Global RNA-seq was performed in Nr2f6 knockdown C2C12 myocytes (N = 4-5). Molecular and metabolic assays and proliferation experiments were performed using stable Nr2f6 knockdown and Nr2f6 overexpression C2C12 cell lines (N = 3-6). Nr2f6 content was evaluated in lipid overload models in vitro and in vivo (N = 3-6). In vivo experiments included Nr2f6 overexpression in mouse tibialis anterior muscle, followed by gene array transcriptomics and molecular assays (N = 4), ex vivo contractility experiments (N = 5), and histological analysis (N = 7). The conservation of Nr2f6 depletion effects was confirmed in primary skeletal muscle cells of humans and mice. RESULTS: Nr2f6 knockdown upregulated genes associated with muscle differentiation, metabolism, and contraction, while cell cycle-related genes were downregulated. In human skeletal muscle cells, Nr2f6 knockdown significantly increased the expression of myosin heavy chain genes (two-fold to three-fold) and siRNA-mediated depletion of Nr2f6 increased maximal C2C12 myocyte's lipid oxidative capacity by 75% and protected against lipid-induced cell death. Nr2f6 content decreased by 40% in lipid-overloaded myotubes and by 50% in the skeletal muscle of mice fed a high-fat diet. Nr2f6 overexpression in mice resulted in an atrophic and hypoplastic state, characterized by a significant reduction in muscle mass (15%) and myofibre content (18%), followed by an impairment (50%) in force production. These functional phenotypes were accompanied by the establishment of an inflammation-like molecular signature and a decrease in the expression of genes involved in muscle contractility and oxidative metabolism, which was associated with the repression of the uncoupling protein 3 (20%) and PGC-1α (30%) promoters activity following Nr2f6 overexpression in vitro. Additionally, Nr2f6 regulated core components of the cell division machinery, effectively decoupling muscle cell proliferation from differentiation. CONCLUSIONS: Our findings reveal a novel role for Nr2f6 as a molecular transducer that plays a crucial role in maintaining the balance between skeletal muscle contractile function and oxidative capacity. These results have significant implications for the development of potential therapeutic strategies for metabolic diseases and myopathies.
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Contração Muscular , Músculo Esquelético , Animais , Camundongos , Músculo Esquelético/metabolismo , Contração Muscular/fisiologia , Humanos , Linhagem Celular , MasculinoRESUMO
Glutamine and glutamate are interconverted by several enzymes and alterations in this metabolic cycle are linked to cardiometabolic traits. Herein, we show that obesity-associated insulin resistance is characterized by decreased plasma and white adipose tissue glutamine-to-glutamate ratios. We couple these stoichiometric changes to perturbed fat cell glutaminase and glutamine synthase messenger RNA and protein abundance, which together promote glutaminolysis. In human white adipocytes, reductions in glutaminase activity promote aerobic glycolysis and mitochondrial oxidative capacity via increases in hypoxia-inducible factor 1α abundance, lactate levels and p38 mitogen-activated protein kinase signalling. Systemic glutaminase inhibition in male and female mice, or genetically in adipocytes of male mice, triggers the activation of thermogenic gene programs in inguinal adipocytes. Consequently, the knockout mice display higher energy expenditure and improved glucose tolerance compared to control littermates, even under high-fat diet conditions. Altogether, our findings highlight white adipocyte glutamine turnover as an important determinant of energy expenditure and metabolic health.
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Adipócitos , Metabolismo Energético , Glutaminase , Camundongos Knockout , Animais , Glutaminase/metabolismo , Camundongos , Humanos , Masculino , Adipócitos/metabolismo , Feminino , Obesidade/metabolismo , Resistência à Insulina , Glutamina/metabolismo , Dieta Hiperlipídica , GlicóliseRESUMO
OBJECTIVES: To determine the risk factors for in-hospital mortality in patients with COVID-19 from a Peruvian national hospital. METHODS: Retrospective cohort study of medical records of patients with COVID-19 hospitalized at Hospital Nacional Hipólito Unanue (HNHU) during the months of April to August 2020. The dependent variable was in-hospital mortality. Independent variables included sociodemographic and clinical characteristics, physical examination findings, oxygen saturation (SaO2) at admission, treatment received during hospitalization and laboratory results at admission. A Cox regression model was used to evaluate the crude and adjusted hazard ratios for associated factors. RESULTS: We included 1418 patients. Median age was 58 years (IQR 47-68 years) and 944 (66.6%) were male. The median length of hospitalization was 7 (4-13) days, and the mortality rate was 46%. The most frequent comorbidities were type 2 diabetes mellitus, hypertension, and obesity. In the adjusted analysis, mortality was associated with age (HR 1.02; 95%CI 1.02-1.03), history of surgery (HR 1.89; 95%CI 1.31-2.74), lower oxygen saturation at admission (HR 4.08; CI95% 2.72-8.05 for SaO2<70% compared to SaO2>94%), the presence of poor general condition (HR 1.81; 95% CI 1.29-2.53), altered state of consciousness (HR 1.58; 95%CI 1.18-2.11) and leukocyte levels (HR 1.01; 95%CI 1.00-1. 02). Treatment with ivermectin (HR 1.44; 95%CI 1.18-1.76) and azithromycin (HR 1.25; 95%CI 1.03-1.52) were associated with higher mortality. Treatment with corticosteroids at low to moderate doses was associated with lower mortality (HR 0.56 95%CI 0. 37-0. 86) in comparison to no steroid use. CONCLUSION: A high mortality was found in our cohort. Low oxygen saturation at admission, age, and the presence of hematological and biochemical alterations were associated with higher mortality. The use of hydroxychloroquine, ivermectin or azithromycin was not useful and was probably associated with unfavorable outcomes. The use of corticosteroids at moderate doses was associated with lower mortality.
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COVID-19/mortalidade , Mortalidade Hospitalar , Adulto , Idoso , COVID-19/epidemiologia , COVID-19/patologia , COVID-19/terapia , Estudos de Coortes , Comorbidade , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Peru/epidemiologia , Encaminhamento e Consulta/estatística & dados numéricos , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2/fisiologiaRESUMO
(1) Background: half-marathon races are popular among recreational runners, with increases in participation among middle-aged and women. We aimed to determine the effects of two half-marathon training programs on hematological and biochemical markers in middle-aged female recreational runners; (2) Methods: ten women (40 ± 7 years) followed moderate intensity continuous training (MICT), based on running volume below 80% VËO2max, and another ten women followed high intensity interval training (HIIT) at 80%-100% VËO2max, with less volume, and combined with eccentric loading exercise. Hematology, plasma osmolality, and plasma markers of metabolic status, muscle damage, inflammatory, and oxidative stress were measured before (S1) and after (S2) training and 24 h after the half-marathon (S3); (3) Results: both training programs had similar moderate effects at S2. However, the acute response at S3 induced different alterations. There was a greater decrease in cholesterol and triglyceride levels in MICT and reductions in markers of damage and inflammation in HIIT. Greater variability in some plasma markers at S3 in MICT suggests that there is inter-individual variability in the response to training; (4) Conclusions: HIIT led to better adaptation to the competition maybe because of the repeated exposure to higher oxygen consumption and eccentric loading exercise.
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Treinamento Intervalado de Alta Intensidade , Adaptação Fisiológica , Exercício Físico , Feminino , Humanos , Corrida de Maratona , Pessoa de Meia-Idade , Consumo de OxigênioRESUMO
BACKGROUND: The Centres for Disease Control and Prevention (CDC) broadened the focus of surveillance from ventilator-associated pneumonia to ventilator-associated event (VAE) for quality purposes. No paediatric definition of VAE (PaedVAE) has been accurately validated. We aimed to analyse the incidence and impact on patient outcomes resulting from the application of the adult and two paediatric VAE (PaedVAE) criteria. SECONDARY OBJECTIVE: to evaluate VAE/PaedVAE as factors associated with increased duration of mechanical ventilation (MV) and Paediatric Intensive Care Unit (PICU) stay. METHODS: Multicentre observational prospective cohort study in 15 PICUs in Spain. VAEs were assessed using the 2013/2015 CDC classification. PaedVAE were assessed using the CDC definition based on mean airway pressure (MAP-PaedVAE) versus a paediatric definition based on positive end-expiratory pressure (PEEP-PaedVAE). Children who underwent MV ≥ 48 h were included. RESULTS: A total of 3626 ventilator-days in 391 patients were analysed. The incidence of VAE, MAP-PaedVAE and PEEP-PaedVAE was 8.55, 5.24 and 20.96 per 1000 ventilator-days, respectively. The median time [IQR] for VAE, MAP-PaedVAE and PEEP-PaedVAE development from the MV onset was 4 [3-12.5], 4 [3-14], and 5 [3-7.75] days, respectively. Among survivors, all three were associated with increased MV duration (> 7 days) and PICU stay (> 10 days) at univariate analysis. Multivariate analysis showed that PEEP-PaedVAE was the only definition independently associated with MV above 7 days [OR = 4.86, 95% CI (2.41-10.11)] and PICU stay [OR = 3.49, 95% CI (1.68-7.80)] above ten days, respectively. CONCLUSIONS: A VAE definition based on slight PEEP increases should be preferred for VAE surveillance in children.
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Pneumonia Associada à Ventilação Mecânica , Ventiladores Mecânicos , Adulto , Criança , Humanos , Unidades de Terapia Intensiva , Pneumonia Associada à Ventilação Mecânica/epidemiologia , Pneumonia Associada à Ventilação Mecânica/prevenção & controle , Estudos Prospectivos , Respiração Artificial/efeitos adversos , Espanha/epidemiologiaRESUMO
Dysregulation of skeletal muscle metabolism influences whole-body insulin sensitivity and glucose homeostasis. We hypothesized that type 2 diabetes-associated alterations in the plasma metabolome directly contribute to skeletal muscle immunometabolism and the subsequent development of insulin resistance. To this end, we analyzed the plasma and skeletal muscle metabolite profile and identified glutamine as a key amino acid that correlates inversely with BMI and insulin resistance index (HOMA-IR) in men with normal glucose tolerance or type 2 diabetes. Using an in vitro model of human myotubes and an in vivo model of diet-induced obesity and insulin resistance in male mice, we provide evidence that glutamine levels directly influence the inflammatory response of skeletal muscle and regulate the expression of the adaptor protein GRB10, an inhibitor of insulin signaling. Moreover, we demonstrate that a systemic increase in glutamine levels in a mouse model of obesity improves insulin sensitivity and restores glucose homeostasis. We conclude that glutamine supplementation may represent a potential therapeutic strategy to prevent or delay the onset of insulin resistance in obesity by reducing inflammatory markers and promoting skeletal muscle insulin sensitivity.
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Diabetes Mellitus Tipo 2 , Resistência à Insulina , Animais , Diabetes Mellitus Tipo 2/metabolismo , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Insulina/metabolismo , Resistência à Insulina/fisiologia , Masculino , Camundongos , Músculo Esquelético/metabolismo , Obesidade/metabolismoRESUMO
The mechanisms promoting disturbed white adipocyte function in obesity remain largely unclear. Herein, we integrate white adipose tissue (WAT) metabolomic and transcriptomic data from clinical cohorts and find that the WAT phosphocreatine/creatine ratio is increased and creatine kinase-B expression and activity is decreased in the obese state. In human in vitro and murine in vivo models, we demonstrate that decreased phosphocreatine metabolism in white adipocytes alters adenosine monophosphate-activated protein kinase activity via effects on adenosine triphosphate/adenosine diphosphate levels, independently of WAT beigeing. This disturbance promotes a pro-inflammatory profile characterized, in part, by increased chemokine (C-C motif) ligand 2 (CCL2) production. These data suggest that the phosphocreatine/creatine system links cellular energy shuttling with pro-inflammatory responses in human and murine white adipocytes. Our findings provide unexpected perspectives on the mechanisms driving WAT inflammation in obesity and may present avenues to target adipocyte dysfunction.
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Adipócitos Brancos , Creatina , Adipócitos Brancos/metabolismo , Animais , Humanos , Inflamação/metabolismo , Camundongos , Obesidade/metabolismo , FosfocreatinaRESUMO
Palytoxin (PTX) is produced by corals such as zoanthid corals. Here we present a case of bilateral PTX-induced keratoconjunctivitis. A 63-year-old man presented to the emergency department with symptoms of red eye, purulent discharge, and foreign body sensation in both eyes. On slit lamp examination, epithelial defects in both eyes with a ring-shaped corneal stromal infiltrate in the right eye and a marginal stromal infiltrate in the left eye were noted. High-resolution anterior segment optical coherence tomography (HR-AS-OCT) showed stromal hyperreflectivity and Descemet folds. Bacterial, fungal, and amoebic cultures were taken. Empirical treatment with topical dexamethasone as well as antibiotics and systemic doxycycline was started. The next day the patient stated that he had been handling zoanthid coral without gloves and had rubbed his eyes afterward. Bilateral PTX-induced keratoconjunctivitis was diagnosed. His eyes were irrigated abundantly with saline solution, and umbilical cord serum eye drops were added to the treatment. Treatment was tapered according to improvement of the corneal infiltrates and epithelial defects. After four months, the stromal infiltrates were resolved but corneal scars persisted in both eyes. HR-AS-OCT showed anterior stromal hyperreflectivity corresponding to corneal leucomas. PTX can cause ocular adverse effects such as keratolysis and corneal inflammation, and in some cases can lead to corneal perforation. It can also produce systemic adverse effects, hence the importance of the preventive measures when handling corals that can produce this toxin.
Assuntos
Venenos de Cnidários , Doenças da Córnea , Ceratoconjuntivite , Acrilamidas , Doenças da Córnea/induzido quimicamente , Doenças da Córnea/diagnóstico , Humanos , Ceratoconjuntivite/diagnóstico , Masculino , Pessoa de Meia-Idade , Tomografia de Coerência ÓpticaRESUMO
Physical exercise has proven to be beneficial to mitigate several deleterious effects associated with neurodegenerative diseases, including Alzheimer's Disease (AD). Here, we investigated the role of long-term exercise as a preventive and therapeutic tool against AD cognitive and behavioral impairments using a sporadic AD-like rat model, established through the administration of streptozotocin (STZ) inside both cerebral ventricles (icv). Six-weeks-old Wistar male rats (56) were divided into groups (either saline or STZ): sedentary (Sed), voluntary physical activity (VPA), VPAâ¯+â¯endurance treadmill training (VPAâ¯+â¯ET) and VPAâ¯+â¯ET only after the injection (VPAâ¯+â¯ET-post). Surgeries occurred at 16wks and the animals were sacrificed at 28 wks. VPA, VPAâ¯+â¯ET, and VPAâ¯+â¯ET-post had continuous access to the running wheels during the entire experimental protocol. VPAâ¯+â¯ET (entire protocol) and VPAâ¯+â¯ET-post (only after surgical procedure) ran 60â¯min/d, 25â¯m/min, 5d/wk in a treadmill. Both ET regimens led to significant improvements in the compromised spatial learning and long-term memory of STZ-infused animals that were not observed neither in the saline Sed nor in VPA STZ groups. General activity patterns and exploration habits were also ameliorated with chronic-exercise in STZ treated animals, while freezing patterns were decreased in these groups. these results were further. Positive alterations were seen in mitochondrial oxygen consumption endpoints (synaptosomal and non-synaptosomal brain mitochondria) that might underlie the neurobehavioral improvements observed. Data suggest that VPA alone was not able to counteract the AD-related deleterious consequences, although when accompanied by endurance training (either lifelong or later-life) may be able to prevent and reverse cognitive and phenotypic impairments associated with AD.
Assuntos
Doença de Alzheimer/terapia , Sintomas Comportamentais/terapia , Cérebro , Treino Aeróbico , Memória de Longo Prazo , Atividade Motora , Condicionamento Físico Animal , Aprendizagem Espacial , Doença de Alzheimer/complicações , Doença de Alzheimer/prevenção & controle , Animais , Sintomas Comportamentais/etiologia , Sintomas Comportamentais/prevenção & controle , Cérebro/metabolismo , Cérebro/fisiopatologia , Modelos Animais de Doenças , Masculino , Memória de Longo Prazo/fisiologia , Atividade Motora/fisiologia , Neurotoxinas/administração & dosagem , Condicionamento Físico Animal/fisiologia , Ratos , Ratos Wistar , Aprendizagem Espacial/fisiologia , Estreptozocina/administração & dosagemRESUMO
Free-running wheel (FRW) is an animal exercise model that relies on high-intensity interval moments interspersed with low-intensity or pauses apparently similar to those performed in high-intensity interval training (HIIT). Therefore, this study, conducted over a 12-weeks period, aimed to compare functional, thermographic, biochemical and morphological skeletal and cardiac muscle adaptations induced by FRW and HIIT. Twenty-four male Wistar rats were assigned into three groups: sedentary rats (SED), rats that voluntarily exercise in free wheels (FRW) and rats submitted to a daily HIIT. Functional tests revealed that compared to SED both FRW and HIIT increased the ability to perform maximal workload tests (MWT-cm/s) (45 ± 1 vs. 55 ± 2 and vs. 65 ± 2). Regarding thermographic assays, FRW and HIIT increased the ability to lose heat through the tail during MWT. Histochemical analyzes performed in tibialis anterior (TA) and soleus (SOL) muscles showed a general adaptation toward a more oxidative phenotype in both FRW and HIIT. Exercise increased the percentage of fast oxidative glycolytic (FOG) in medial fields of TA (29.7 ± 2.3 vs. 44.9 ± 4.4 and vs. 45.2 ± 5.3) and slow oxidative (SO) in SOL (73.4 ± 5.7 vs. 99.5 ± 0.5 and vs. 96.4 ± 1.2). HITT decreased fiber cross-sectional area (FCSA-µm2) of SO (4350 ± 286.9 vs. 4893 ± 325 and vs. 3621 ± 237.3) in SOL. Fast glycolytic fibers were bigger across all the TA muscle in FRW and HIIT groups. The FCSA decrease in FOG fibers was accompanied by a circularity decrease of SO from SOL fibers (0.840 ± 0.005 vs. 0.783 ± 0.016 and vs. 0.788 ± 0.010), and a fiber and global field capillarization increase in both FRW and HIIT protocols. Moreover, FRW and HIIT animals exhibited increased cardiac mitochondrial respiratory control ratio with complex I-driven substrates (3.89 ± 0.14 vs. 5.20 ± 0.25 and vs. 5.42 ± 0.37). Data suggest that FRW induces significant functional, physiological, and biochemical adaptations similar to those obtained under an intermittent forced exercise regimen, such as HIIT.
RESUMO
In this study, we propose a novel three-criteria performance score to semiquantitatively classify the running style, the degree of involvement and compliance and the validity of electric shock count for rats exercising on a treadmill. Each score criterion has several style-marks that are based on the observational registry of male Sprague-Dawley rats running for 4-7 weeks. Each mark was given a score value that was averaged throughout a session-registry and resulting in a session score for each criterion, ranging from "0" score for a hypothetical "worst runner", to score "1" for a hypothetical "perfect runner" rat. We found significant differences throughout a training program, thus providing evidence of sufficient sensitivity of this score to reflect the individual evolution of performance improvement in exercise capacity due to training. We hypothesize that this score could be correlated with other physiological or metabolic parameters, thus refining research results and further helping researchers to reduce the number of experimental subjects.