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BACKGROUND: Data on the physiological impact of tracheal intubation and positive end-expiratory pressure (PEEP) on respiratory mechanics in anesthetized children are scarce. We aimed to evaluate the mechanical effects of intubation and PEEP in children without lung pathology under general anesthesia. METHODS: Prospective physiologic experimental crossover study, in children under 15 years scheduled for elective surgery. After anesthesia induction and neuromuscular blockade, volume-controlled ventilation was initiated. Respiratory mechanics were assessed before (mask ventilation) and after tracheal intubation, at PEEP 0 and 5 cmH2O. Measured variables included peak inspiratory (PIP), plateau (PPLAT), and total expiratory pressures (tPEEP). Calculated parameters were compliance (Crs), driving pressure (ΔP), and mechanical power (MP). A mixed linear regression model was used. RESULTS: 60 patients were included. Median age 58.0 (18.0-84.0) months. Intubation increased PIP-PPLAT + 23.9% (p < 0.001), Raw +16.4% (p = 0.011), and ΔP + 20.4% (p < 0.001); and decreased Crs -14% (p = 0.001). PEEP during mask ventilation reduced ΔP 29.1% (p < 0.001) and increased Crs 46.7% (p < 0.001). Combined intubation and PEEP reduced ΔP (-7.9%, p = 0.002) and increased Crs (+19.6%, p < 0.001). PEEP raised MP both during mask ventilation (+50%) and after intubation (+83.3%, both p < 0.001). Children under 2 years showed higher Raw than older children across all conditions (p < 0.001), but similar behavior in ΔP and Crs. CONCLUSION: PEEP and intubation induce changes in respiratory mechanics. While tracheal intubation increases PIP and ΔP, and decreases Crs, the addition of PEEP partially mitigates these effects on airway pressures, but not on MP. These results suggest a deterioration of both the resistive and elastic components during MV. TRIAL REGISTRATION: This project was registered and approved for implementation by the Pediatric Hospital Center Pereira Rossell Institutional Review Board and registered in the Ministry of Public Health (#7647719). Informed and signed consent was obtained from all the children's parents or responsible guardians. All procedures in this study were performed in accordance with the Declaration of Helsinki.
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Anestesia Geral , Intubação Intratraqueal , Respiração com Pressão Positiva , Mecânica Respiratória , Humanos , Respiração com Pressão Positiva/métodos , Criança , Pré-Escolar , Masculino , Feminino , Estudos Prospectivos , Intubação Intratraqueal/métodos , Mecânica Respiratória/fisiologia , Estudos Cross-Over , Lactente , AdolescenteRESUMO
OBJECTIVE: To determine whether inflating high-volume, low-pressure (HVLP) endotracheal tube (ETT) cuffs to 30 cmH2O prevents significant gas leakage (>5 mL) during intermittent positive-pressure ventilation (IPPV) in rigid in vitro and ex vivo porcine tracheal models, and whether ETT cuff lubrication reduces the pressure needed for an effective airway seal. STUDY DESIGN: Prospective, randomised, crossover design. ANIMALS: A group of 20 porcine excised tracheae. METHODS: Phase 1: In a rigid in vitro tracheal model (PVC tube, 22 mm inner diameter, 30 ° incline) connected to a 1 L test lung delivering IPPV (peak inspiratory pressure 10 cmH2O, 12 breaths minute-1, inspiratory:expiratory ratio 1:3), randomly selected HVLP ETTs (five per size, 7.0-10.0 mm inner diameter) were inserted and cuffs inflated to 30 cmH2O. Gas leakage during IPPV, determined as inspiratory-expiratory volume difference (ΔI-E), was measured 12 times per ETT, before and after water-soluble gel lubrication. Phase 2 replicated the experiments using 20 ex vivo porcine tracheae [20 mm ± 2 mm inner diameter (mean ± standard deviation)]. Finally, minimum cuff pressures required to achieve negligible leakage (≤5 mL) were determined before and after lubrication. Statistical analyses included t-tests, Wilcoxon signed-rank, and Kruskal-Wallis tests, with Conover-Iman post hoc and Bonferroni corrections. RESULTS: In vitro, median ΔI-E before lubrication was 155 mL (7.0 mm), 77 mL (8.0 mm), 27 mL (9.0 mm), and 20 mL (10.0 mm). Lubrication reduced leakage (p < 0.0001) and cuff pressures by 8.7 ± 10.4 to 22 ± 4.2 cmH2O. Ex vivo, median ΔI-E before lubrication was 22 mL (7.0 mm), 20 mL (8.0 mm), 19 mL (9.0 mm), and 12 mL (10.0 mm). Lubrication reduced leakage (p < 0.0001) and cuff pressures by 3.4 ± 1.5 to 12 ± 9.5 cmH2O. Leakage differed significantly between sizes before and after lubrication (p < 0.0001). CONCLUSIONS: Inflating HVLP ETT cuffs to 30 cmH2O alone did not reliably prevent gas leakage, but lubrication significantly reduced leakage and the cuff pressure required for an effective airway seal, particularly in smaller ETTs.
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Intubação Intratraqueal , Animais , Intubação Intratraqueal/veterinária , Intubação Intratraqueal/instrumentação , Suínos , Lubrificação , Géis , Estudos Cross-Over , Respiração com Pressão Positiva/veterinária , Traqueia , Gases , Estudos ProspectivosRESUMO
OBJECTIVE: To assess how chronotherapy influences recovery after bilateral third molar extraction when Dexketoprofen is administered as an anti-inflammatory agent. MATERIAL AND METHODS: A randomized cross-over controlled trial with 10 patients with bilateral impacted third molar extraction was enrolled. For 7 days after the surgery, the chronotherapy group was prescribed one dose of Dexketoprofen (25 mg) limited to daytime, while the control group were given two doses per day (every 12 h). Pain intensity was recorded at baseline, 24, 48, and 72 h, while facial swelling parameters were evaluated at baseline, 24, 72, and 168 h (Day 7) postoperatively. Also, the inflammatory profile was analyzed for each patient by blood samples at baseline, 72 and 168 h. The concentrations of IL-1ß, IL-1a, IL-2, IL-4, IL-6, IL-7, IL-10, and IL-13 were measured using high-sensitivity multiplex map human immunoassays. RESULTS: No significant differences in postoperative VAS pain, swelling, and mouth opening (trismus) measures were observed between the two groups. However, the chronotherapy group had reduced overall postoperative complications compared to the control group. Regarding postoperative recovery, pain intensity scores in the chronotherapy group at 24, 48, and 72 h indicated a faster recovery than the control group. Blood samples analysis showed no statistical differences between the different inflammatory markers studied at 72 h or Day 7 in both groups. CONCLUSIONS: Daytime administration of NSAIDs might be sufficient to manage postoperative pain after third molar extraction, and complications were similar between both groups. CLINICAL TRIAL REGISTRATION: clinicaltrials. gov, Identifier database: NCT05176158.
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Anti-Inflamatórios não Esteroides , Cetoprofeno , Dente Serotino , Dor Pós-Operatória , Extração Dentária , Dente Impactado , Trometamina , Humanos , Dente Serotino/cirurgia , Extração Dentária/efeitos adversos , Estudos Cross-Over , Feminino , Anti-Inflamatórios não Esteroides/administração & dosagem , Cetoprofeno/análogos & derivados , Cetoprofeno/administração & dosagem , Projetos Piloto , Dor Pós-Operatória/tratamento farmacológico , Dor Pós-Operatória/prevenção & controle , Adulto , Masculino , Adulto Jovem , Trometamina/administração & dosagem , Fatores de Tempo , Esquema de Medicação , Dente Impactado/cirurgia , Medição da DorRESUMO
BACKGROUND: Hypoglycaemia stimulates growth hormone (GH) secretion, whereas hyperglycaemia suppresses it. However, the underlying mechanisms are not fully understood, particularly the potential role of gut-derived hormones released in response to oral glucose. AIM: To investigate whether GH suppression is modulated by the route of glucose administration. METHODS: A two-day intervention study in healthy volunteers. GH, insulin, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP) responses during a 2-h oral glucose tolerance test (OGTT) were compared with those during a 2-h isoglycaemic intravenous (IV) glucose infusion. GH levels were analyzed using paired t-test of GH concentrations at every blood sample time point. The effect of intervention on all measured hormones were also assessed by paired t-test of Area Under the Curve (AUC). RESULTS: 12 healthy volunteers (6 females, mean age 47.9 ± 5.4 years) were included. In 9 of the 12 subjects, IV glucose induced an early peak in plasma-GH followed by a decrease. At 20 min after glucose intake GH levels increased by 46% during IV glucose compared to a decrease of 17% during oral glucose. The biggest numerically difference in GH between oral vs IV glucose was seen at 45 min (median [range], 0.30 [0.05-1.13] vs. 0.46 [0.05-9.82] µg/l, p = 0.072). There was no difference between AUC of GH levels (p = 0.381). During IV glucose, two subjects did not reach the threshold for excluding acromegaly. Oral glucose showed significant increases compared to IV glucose for insulin (p < 0.001), GLP-1 (p = 0.002) and GIP (p < 0.001) when using paired t-test of AUC. CONCLUSIONS: Route of glucose exposure might influence the suppressive effect of glucose on GH secretion. This finding suggests that stimulation of other hormone systems may play a contributing role on the regulation of GH. The potential mechanism behind remains elusive but changes in gut-derived hormones might be of importance.
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Glucose , Hormônio do Crescimento Humano , Humanos , Feminino , Masculino , Hormônio do Crescimento Humano/sangue , Estudos Cross-Over , Glucose/administração & dosagem , Administração Oral , Adulto , Pessoa de Meia-Idade , Voluntários Saudáveis , Teste de Tolerância a Glucose , Glicemia/metabolismo , Insulina/sangue , Peptídeo 1 Semelhante ao Glucagon/sangue , Polipeptídeo Inibidor Gástrico/sangue , Administração IntravenosaRESUMO
The deployment of 5G networks utilizing millimeter-wave frequencies such as 26 GHz has raised concerns about potential neurophysiological effects. However, no controlled studies have investigated the impact of 26 GHz exposure on human brain electrical activity. We conducted a randomized, triple-blind crossover study in 31 healthy young adults (18 men, 14 women, mean age 26.1 ± 5.2 years). Participants underwent two sessions (real and sham exposure) separated by one week, with 26.5-min exposure to 26 GHz electromagnetic fields at 2 V/m. EEG activity was recorded before, during, and after exposure. Power spectral density was computed for delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), and beta (12-35 Hz) frequency bands. Statistical analysis employed mixed-effects models with baseline correction, examining exposure effects across temporal phases and electrode clusters. No significant modulation of EEG frequency bands was observed during eyes-closed conditions following 26 GHz exposure. Mixed-effects modeling revealed no significant main effects or interactions for exposure conditions across all frequency bands and electrode clusters. This first controlled investigation of 26 GHz 5G effects on human EEG activity found no detectable alterations in brain electrical activity under regulatory-compliant exposure conditions. These findings contribute important preliminary safety data for 5G millimeter-wave technology deployment, though further research across diverse populations and exposure scenarios remains warranted.
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Encéfalo , Campos Eletromagnéticos , Humanos , Masculino , Feminino , Campos Eletromagnéticos/efeitos adversos , Adulto , Encéfalo/efeitos da radiação , Encéfalo/fisiologia , Estudos Cross-Over , Eletroencefalografia , Adulto JovemRESUMO
AIMS: The incretin hormones glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide 1 (GLP-1) influence metabolism through strong effects on pancreatic hormone secretion but also in a pancreas-independent manner. Here, we investigated the isolated extrapancreatic effects of endogenous GIP and GLP-1 by applying hormone receptor antagonists in totally pancreatectomized individuals. METHODS: Twelve totally pancreatectomized individuals each underwent four 270-min liquid mixed meal tests (480 kcal) in a randomized study design with infusions of the GIP receptor antagonist GIP(3-30)NH2 (800 pmol/kg/min), the GLP-1 receptor antagonist exendin(9-39)NH2 (450 pmol/kg/min), GIP(3-30)NH2 + exendin(9-39)NH2, and saline (placebo), respectively. Blood samples, appetite-related measures, heart rate, blood pressure, and ad libitum food intake data were collected. Participants continued their basal insulin but omitted bolus insulin in the morning of the experiment. RESULTS: Infusions of GIP(3-30)NH2 and GIP(3-30)NH2 + exendin(9-39)NH2 attenuated meal-induced inhibition of bone resorption (carboxy-terminal collagen crosslinks) (nadir [mean ± SD] to 84 ± 9% and to 85 ± 8% of baseline, compared to placebo (64 ± 15%) (ps <0.05)). During exendin(9-39)NH2 and exendin(9-39)NH2 + GIP(3-30)NH2 co-infusion, GLP-1 plasma responses increased (ps <0.05). Infusion of GIP(3-30)NH2 or exendin(9-39)NH2 did not affect other measurements. CONCLUSION: Endogenous GIP contributes to the regulation of postprandial bone resorption independently of pancreatic factors. In contrast, GIP receptor and/or GLP-1 receptor antagonism had no measurable effects on glucose metabolism, gastric emptying, appetite, food intake, triglycerides, or haemodynamics, supporting a pancreatic contribution to some of these effects of the endogenous hormones, although the surgical reconstruction may have influenced the sensitivity of the targets.
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Polipeptídeo Inibidor Gástrico , Receptor do Peptídeo Semelhante ao Glucagon 1 , Pancreatectomia , Fragmentos de Peptídeos , Receptores dos Hormônios Gastrointestinais , Humanos , Polipeptídeo Inibidor Gástrico/farmacologia , Polipeptídeo Inibidor Gástrico/administração & dosagem , Masculino , Feminino , Método Duplo-Cego , Receptores dos Hormônios Gastrointestinais/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Fragmentos de Peptídeos/administração & dosagem , Receptor do Peptídeo Semelhante ao Glucagon 1/antagonistas & inibidores , Estudos Cross-Over , Pessoa de Meia-Idade , Adulto , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Apetite/efeitos dos fármacos , Período Pós-Prandial/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon , Frequência Cardíaca/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , InsulinaRESUMO
Oral nicotine pouches (NPs), although addictive and not risk-free, have potential application for a tobacco harm reduction approach. This study aims to further characterize their ability to deliver nicotine effectively. This randomized seven-way crossover PK study in healthy oral pouch consumers evaluated 11 and 20 mg NPs used for 10, 20, and 30 min, and for 30 min with expulsion of saliva. Used pouches were analyzed for extracted nicotine, flavor components, and sweeteners. The Cmax and AUC0-4 h increased with nicotine strength and usage time (18.9-21.6 and 26.7-33.6 ng/mL; 24.6-43.0 and 36.4 to 65.6 h ng/mL for the 11 and 20 mg NPs, respectively). Extracted nicotine was greater for the 11-mg than for the 20-mg NP, (10 min, 28.0% vs. 22.4%; 20 min, 35.8% vs. 29.6%; 30 min, 43.7% vs. 36.9%, respectively). Only 1.8% of the nicotine measured in the reference NPs was detected in saliva collected over the 30 min use period. Use of 20-mg NP for 30 min resulted in the extraction of 30.1% flavor components and 17.3% sweeteners, but only 0.16% and 3.4% of the amount measured in the reference NPs were detected in saliva, respectively. Thus, very little nicotine, flavor components, and sweeteners were swallowed during NP use. This study shows NPs can deliver nicotine effectively to satisfy smokers' nicotine desire. Nicotine delivery to the consumer increases with the duration of use. Our findings suggest that smokers who switch completely to an NP can obtain their accustomed amount of nicotine during normal product use. International Standard Registered Clinical Trial number: ISRCTN12265853.
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Nicotina , Humanos , Estudos Cross-Over , Masculino , Nicotina/farmacocinética , Nicotina/administração & dosagem , Nicotina/sangue , Adulto , Feminino , Adulto Jovem , Saliva/metabolismo , Saliva/química , Administração Oral , Pessoa de Meia-Idade , Área Sob a Curva , Voluntários SaudáveisRESUMO
INTRODUCTION: The purpose of this quality improvement project (QIP) was to identify factors contributing to mental and physical fatigue in major abdominal surgery and to attempt to mitigate the same by incorporating mini hydration breaks with targeted muscle stretches at regular intervals. METHODS: This prospective QIP was conducted in the Peritoneal Malignancy Unit of a national referral centre for peritoneal malignancy-related diseases between February and April 2022. Only procedures lasting longer than four hours were included and all theatre personnel were invited to participate. A baseline survey was conducted to ascertain the impact of mental and physical fatigue. Subsequently, a cross-over study design was utilised; for the first four weeks the procedure was performed with no breaks. This was followed with four weeks of intervention (hydration breaks and muscle stretches). Validated questionnaires (pain scores, occupational fatigue inventory and surgical task load measurement) were used to measure perceived physical and mental fatigue. RESULTS: Over half (58%) of the 34 participants felt that surgical discomfort affected their stamina, posture and ability to concentrate. Work-life balance was affected in 44%, and 17% felt that it affected their sleep pattern with a minority considering shortening their careers. A reduction in the mean pain score at the end of the day in the group who had breaks (2.61 vs 2.16) was noted. There was global improvement in situational stress, distractibility, temporal and mental demands in the group who had regular breaks, amounting to improvements in self-perceived fatigue levels. CONCLUSIONS: Theatre personnel involved in major surgery experience mental and physical stress that adversely affects work-life balance. Regular, short hydration breaks with muscle stretches can help improve mental and physical wellbeing of theatre personnel involved in major abdominal surgery.
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Abdome , Fadiga , Fadiga Mental , Doenças Profissionais , Humanos , Fadiga/prevenção & controle , Fadiga/etiologia , Estudos Prospectivos , Masculino , Feminino , Fadiga Mental/prevenção & controle , Fadiga Mental/etiologia , Abdome/cirurgia , Pessoa de Meia-Idade , Estudos Cross-Over , Adulto , Melhoria de Qualidade , Inquéritos e Questionários , Doenças Profissionais/prevenção & controleRESUMO
BACKGROUND: Dialytic sodium removal (DSR) is an important parameter of peritoneal dialysis (PD) adequacy. The aim of this study was to report the DSR of children with acute kidney injury (AKI) on a standard acute PD prescription and to compare it to that of children on continuous flow peritoneal dialysis (CFPD). METHODS: A secondary analysis of prospectively collected data was performed from a published randomized controlled crossover trial comparing children on conventional PD and CFPD. The conventional PD prescription used: fill volume 20 mL/kg, glucose 2.5%, dwell time 45-60 min. In this study, we described and compared DSR in 15 children with AKI receiving PD and CFPD. Relative ultrafiltration through small pore (UFSP) was also described and compared. RESULTS: The median (range) weight and age of patients were 5.8 (2.3-14.0) kg and 6 (0.2-14) months. Approximately 8 h of dialysis was received per patient per modality. Results were then extrapolated and expressed per day. The mean ± SD DSR on conventional PD and CFPD were 2.7 ± 6 and 8.4 ± 10 mmol /kg/day, respectively (P = 0.02). The mean ± SD sodium dialysate to plasma (D/P) ratio on conventional PD and CFPD were 0.94 ± 0.03 and 0.94 ± 0.04 mmol/mmol (P = 1.0). Mean ± SD UFSP to total UF ratios on conventional PD and CFPD were 0.82 ± 0.39 and 0.66 ± 0.51 mL/mL (P = 0.14). CONCLUSIONS: This study adds to the limited data on DSR in children on PD for AKI. CFPD removes more salt compared to conventional PD because of increased ultrafiltration (UF). A high percentage of UF was through small pores in both modalities.
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Injúria Renal Aguda , Soluções para Diálise , Diálise Peritoneal , Sódio , Humanos , Diálise Peritoneal/métodos , Injúria Renal Aguda/terapia , Injúria Renal Aguda/sangue , Masculino , Feminino , Sódio/sangue , Pré-Escolar , Lactente , Estudos Cross-Over , Criança , Soluções para Diálise/química , Estudos Prospectivos , Resultado do TratamentoRESUMO
BACKGROUND AND OBJECTIVE: Post-induction hypotension (PIH), primarily resulting from the vasodilatory effects and reduced cardiac output induced by anesthetic agents, is widespread among patients with pre-existing cardiovascular conditions or those who have experienced suboptimal fluid management. This condition can lead to inadequate perfusion of critical organs such as the brain and heart, increasing the risk of lengthy postoperative recovery, complications, and mortality. Therefore, early identification and prediction of PIH are crucial for improving postoperative management and patient outcomes. METHODS: This study utilized data from 440 elderly patients experiencing elective surgery under general anesthesia at the Ningbo University Affiliated People's Hospital. Patients were categorized into PIH and non-PIH groups based on their mean arterial pressure at the time of induction. To predict PIH, the study developed a machine-learning model named bECRIME-SVM. The model employed an exemplar learning strategy enhanced by a crossover restart strategy within the rime optimization algorithm (ECRIME) to select optimal feature subsets. These subsets were then evaluated using a support vector machine (SVM) to assess their predictive efficacy for PIH. RESULTS: The bECRIME-SVM model demonstrated strong performance on the PIH dataset, achieving a prediction accuracy of 84.100 % and a specificity of 85.287 %. Comparative analysis with other models from the CEC 2017 benchmark functions confirmed the superior optimization capability and convergence accuracy of the ECRIME algorithm. The model also identified several key predictive features, including diabetes, drinking history, atropine, ß-blockers, total cholesterol, and pre-induction systolic blood pressure. CONCLUSIONS: The bECRIME-SVM model provides a valuable tool for the clinical prediction of PIH, with high accuracy and specificity. Identifying significant predictive features offers essential insights for the early detection and management of PIH, ultimately contributing to improved postoperative outcomes for patients undergoing general anesthesia.
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Hipotensão , Aprendizado de Máquina , Humanos , Idoso , Hipotensão/diagnóstico , Hipotensão/etiologia , Feminino , Masculino , Máquina de Vetores de Suporte , Algoritmos , Anestesia Geral/efeitos adversos , Estudos Cross-Over , Idoso de 80 Anos ou maisRESUMO
OBJECTIVE: The evidence of the effects of non-nutritive sweeteners (NNS) on glucose-regulating hormones is heterogeneous. We aimed to evaluate the acute effects of three types of soft drinks sweetened with sucrose and/or NNS on glucose and hormone responses. METHODS: We conducted a randomized crossover clinical trial involving 20 adults. Participants ingested 355 mL of carbonated water (CON) and three beverages sweetened with aspartame/acesulfame K (AAK), sucrose/stevia (SUC/STE), and sucrose (SUC), with a 7-day washout period between each trial. Glucose, insulin, glucagon, glucose-dependent insulinotropic peptide (GIP), pancreatic polypeptide (PP), leptin, and ghrelin levels were measured at 0, 30, 60, 90, and 120 minutes, in addition to the area under the curve (AUC). RESULTS: The SUC beverage elicited the highest glucose and insulin responses, with significant increases at 30 minutes (P < 0.001). In contrast, SUC/STE resulted in a glucose-lowering effect at 60 minutes (-12.5 mg/dL, P < 0.05) and a sustained increase in PP levels, which peaked at 120 minutes (+73.4 pg/mL, P < 0.05). AAK and CON showed no significant differences in glucose or hormone levels. CONCLUSION: This study highlights the differential effects of sucrose- and NNS-sweetened beverages on glucose metabolism and hormonal responses. The glucose-lowering and PP-stimulating effects of SUC/STE suggest potential benefits for glycemic control and satiety. These findings provide insights into the metabolic impact of NNS and their potential role in dietary recommendations for health promotion.
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Glicemia , Bebidas Gaseificadas , Hormônios Gastrointestinais , Adoçantes não Calóricos , Sacarose , Edulcorantes , Humanos , Estudos Cross-Over , Masculino , Adulto , Feminino , Adoçantes não Calóricos/farmacologia , Adoçantes não Calóricos/administração & dosagem , Sacarose/farmacologia , Sacarose/administração & dosagem , Insulina/sangue , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Grelina/sangue , Glucagon/sangue , Adulto Jovem , Leptina/sangue , Stevia , Polipeptídeo Inibidor Gástrico/sangue , Aspartame/farmacologia , Polipeptídeo Pancreático/sangue , Edulcorantes/farmacologia , Hormônios Gastrointestinais/sangue , TiazinasRESUMO
Research shows that mental fatigue (MF) can negatively impact physical performance. However, the effects of MF during football match-play are not well understood, particularly in women, and its impact on psychological factors is less known (e.g., attentional focus). This study explored the physical and psychological effects of MF in women's football during 7 vs. 7 small-sided games (SSGs). 14 Women's National League players (M age = 25.9 ± 5.9 years) participated. A counterbalanced cross-over design was implemented involving a MF (30-min social media use), and a control condition (30-min sitting with teammates with no phone access) prior to 3 × 7-min SSGs, interspersed with 2-min rest. GPS was used to monitor work output. Participants had microphones attached and were asked to 'think aloud' (TA) during SSGs; content analysis was used to examine players' attentional focus and communication. MF (visual analogue scale) and fatigue (BRUMS) increased pre-to post-MF (+1.95 ± 1.45, p < .001; +2.57 ± 3.33, p = .038) but in control (p = 1.00), and happiness (BRUMS) was lower in MF vs. control (-1.96 ±0 .68, p = .013). No differences were found between conditions for work output or RPE (ps > 0.05). Total TA was lower (p = .046) and there was less positive performance-related TA (p = .022) in MF (22.53 ± 13.11; 0.15 ± 0.38) vs. control (30.00 ± 17.84; 1.54 ± 2.11). There was more negative non-performance related communication (p = .031), and less joking with teammates (p = .020) with MF (0.85 ± 1.07; 1.69 ± 1.80) vs. control (0.08 ± 0.28; 4.39 ± 3.78). In sum, 30-min social media use was associated with reduced happiness, vigour and heightened perceptions of fatigue, and effected how able participants were to engage in TA, how positive their thoughts were, and how they communicated with teammates. Avoiding phone use prior to training and match-play may be worth considering. Further team-sport research could incorporate TA methods which the present study showed to be feasible, to understand more on players' cognitive processing in match-play.
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Desempenho Atlético , Fadiga Mental , Futebol , Humanos , Fadiga Mental/psicologia , Feminino , Adulto , Desempenho Atlético/psicologia , Futebol/psicologia , Atenção , Estudos Cross-Over , Adulto Jovem , FelicidadeRESUMO
Dietary nitrate ([Formula: see text]), a source of nitric oxide (NO), enhances muscle contractility in numerous populations, but it is still unclear whether young women also benefit. The efficacy of [Formula: see text] supplementation might vary with menstrual cycle phase, due to lower endogenous NO bioavailability when estradiol (E2) is low. Using a double-blind, placebo-controlled, crossover design, we determined the effects of acute ingestion of 200 µmol/kg of [Formula: see text] (from concentrated beetroot juice) or placebo on muscle function in 12 normally menstruating women during the early follicular (EF) and late follicular (LF) phases of their cycle. Muscle function was determined through maximal knee extensions on an isokinetic dynamometer and electrical stimulation of the quadriceps, with menstrual phase confirmed through plasma hormone measurement. E2 concentrations were significantly lower in EF versus LF (220 ± 90 vs. 583 ± 260 pM; P < 0.001), whereas progesterone levels did not differ. Despite this, dietary [Formula: see text] had no effect on maximal muscle power or velocity during either phase. Dietary [Formula: see text] also had no effect on unpotentiated or potentiated peak twitch torque, rate of torque development (RTD), rate of relaxation (RR), or the torque frequency relationship during either phase. However, the RTD was 2%-8% greater in the LF versus EF phase, especially in the unpotentiated state (P < 0.01). The RR was also 9% slower in the LF versus EF phase (P < 0.05). Variations in E2 during the menstrual cycle seem to subtly influence muscle contractile function. Acute [Formula: see text] supplementation, on the contrary, has no apparent effect on muscle contractility in young women.NEW & NOTEWORTHY We determined the effects of dietary [Formula: see text] on muscle contractile function during the early follicular (EF) and late follicular (LF) phases of the menstrual cycle. Although [Formula: see text] supplementation had no impact on muscle contractility, during electrically evoked twitches, the rate of torque development was greater, and the rate of relaxation was slower, in the LF phase. These findings enhance our understanding of how dietary [Formula: see text] and female sex hormones impact muscle contractile function.
Assuntos
Ciclo Menstrual , Contração Muscular , Nitratos , Humanos , Feminino , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Método Duplo-Cego , Ciclo Menstrual/fisiologia , Ciclo Menstrual/efeitos dos fármacos , Adulto Jovem , Adulto , Nitratos/administração & dosagem , Nitratos/farmacologia , Estradiol/sangue , Estradiol/metabolismo , Estudos Cross-Over , Progesterona/sangue , Suplementos Nutricionais , Torque , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/fisiologia , Força Muscular/efeitos dos fármacos , Força Muscular/fisiologia , Fase Folicular/fisiologia , Óxido Nítrico/metabolismo , Estimulação ElétricaRESUMO
BACKGROUND: Dairy products are important sources of macro/micronutrients and contain bioactive components with anti-inflammatory, antioxidant, and musculoskeletal supporting properties. Few studies have assessed the short-term effect of consuming a variety of wholefood dairy products (as opposed to single foods/nutrients) on a range of interrelated inflammatory, metabolic, antioxidant and vascular outcomes. OBJECTIVES: To compare these physiological outcomes after 6 wks of a high mixed-dairy diet compared with 6 wks of a low dairy diet. METHODS: Using a randomly assigned crossover design, 30 adults (18 females/12 males) with overweight/obesity (OW/OB) (BMI: 32.0 ± 4.5 kg/m2] and pre-existing cardiometabolic disease risk factors completed two 6-wk dietary intervention conditions in random order (separated by a ≥4-wk washout); 1) a high-dairy (HD) diet (3 servings/d of a mix of low-fat milk, Skyr yogurt, full-fat cheddar cheese) and 2) their habitually low-dairy (LD) diet (≤1 serving/d). At baseline and then 6 wks later, fasted blood samples were collected, body composition was assessed, and vascular measurements were taken. RESULTS: After controlling for age, BMI, sequence and period, there were no condition∗time interactions for interleukin-6 (IL-6; primary endpoint); however, there were condition∗time interactions for tumor necrosis factor-alpha (TNF-α; P = 0.042), and IL-4 (P = 0.026) such that they decreased and increased, respectively, on the HD diet compared with the LD diet. No other condition∗time interactions were observed for the other outcomes but we did observe sex∗condition interactions for IL-6 (P = 0.011), TNF-α (P < 0.001), triglycerides (P = 0.014), and diastolic blood pressure (P = 0.045), which were higher during the HD condition in males. CONCLUSIONS: Increasing mixed dairy product intake for 6 wks favorably modulated some cytokines in the absence of metabolic, vascular, body weight, or fat changes. Differences in biomarker concentrations in relation to dairy intake and/or exercise may also be influenced by sex; however, this should be further explored. Overall, increased dairy intake may help ameliorate inflammation in individuals with OW/OB and cardiometabolic dysfunction. This trial was registered at clinicaltrials.gov as NCT04902417.
Assuntos
Citocinas , Laticínios , Inflamação , Obesidade , Sobrepeso , Humanos , Masculino , Feminino , Estudos Cross-Over , Obesidade/sangue , Sobrepeso/sangue , Adulto , Pessoa de Meia-Idade , Citocinas/sangue , Inflamação/sangue , DietaRESUMO
BACKGROUND: Cannabis has shown mixed results in its association with alcohol urge, which may be explained by individual differences. One such factor, working memory capacity (WMC) is associated with drug-related cue reactivity and implicated in alcohol use and problems. In the current study, we examined whether WMC moderates the acute effect of cannabis on alcohol urge in a randomized placebo-controlled crossover trial. METHODS: Participants aged 21 to 44 (N = 125, 32 % female) reporting heavy alcohol use and cannabis use ≥ twice weekly completed a laboratory protocol across three days where they smoked a placebo, 3.1 % delta-9 tetrahydrocannabinol (THC), and 7.2 % THC cannabis cigarette. Participants were asked to rate their alcohol urge pre and post smoking. Prior to the experimental sessions, participants completed WMC measures including the n-back and the complex span tasks, operation span (OS) and symmetry span (SS). RESULTS: Those with higher WMC, as assessed via the SS task, reported significantly lower alcohol urge after smoking the 7.2 %, but not the 3.1 %, THC dose, relative to placebo. Performance on the OS task was not associated with alcohol urge. Lower WMC as determined via n-back scores was associated with higher alcohol urge overall, but n-back scores did not moderate the impact of cannabis on alcohol urge. CONCLUSION: Findings suggest individuals with higher but not lower working memory experience lower alcohol urge under acute effects of cannabis. Although cannabis is increasingly perceived as a substitute for alcohol, individuals with lower working memory may be less likely to experience such benefits when attempting to reduce their drinking.
Assuntos
Consumo de Bebidas Alcoólicas , Fissura , Dronabinol , Fumar Maconha , Memória de Curto Prazo , Humanos , Memória de Curto Prazo/efeitos dos fármacos , Feminino , Masculino , Adulto , Dronabinol/farmacologia , Estudos Cross-Over , Adulto Jovem , Fissura/efeitos dos fármacos , Método Duplo-Cego , Fumar Maconha/psicologia , Consumo de Bebidas Alcoólicas/psicologiaRESUMO
Heroin use disorder (HUD) presents significant global health challenges, with cravings, emotional dysregulation, and cognitive impairments being key barriers to successful recovery. This study explores the acute effects of aerobic and resistance exercise on craving, emotional state, attentional bias, and executive functions in individuals with HUD. A crossover design was employed with 30 male participants diagnosed with HUD, each completing three interventions: high-intensity aerobic exercise (AEC), resistance exercise (REC), and a sedentary control condition (SCC). Assessments were conducted at 10 and 50 minutes post-intervention using a VAS for cravings, a Mood Adjective Checklist for emotional state, a dot-probe task for attentional bias, and Stroop, n-back, and More-Odd Switching tasks for executive functions. Results revealed that both AEC and REC significantly reduced craving and initial attentional bias toward drug-related cues. Both exercise conditions also improved emotional states, inhibitory control, and working memory. No significant differences were observed between the two exercise conditions, and neither exercise significantly influenced sustained attentional bias or cognitive flexibility. These findings suggest that both aerobic and resistance exercises are effective in reducing cravings, enhancing mood, and improving executive functions in HUD patients. The results provide support for incorporating structured exercise programs into addiction recovery frameworks to mitigate relapse risks.
Assuntos
Viés de Atenção , Fissura , Função Executiva , Terapia por Exercício , Exercício Físico , Dependência de Heroína , Treinamento Resistido , Humanos , Masculino , Fissura/fisiologia , Adulto , Dependência de Heroína/reabilitação , Dependência de Heroína/terapia , Dependência de Heroína/psicologia , Função Executiva/fisiologia , Estudos Cross-Over , Exercício Físico/fisiologia , Exercício Físico/psicologia , Pessoa de Meia-Idade , Viés de Atenção/fisiologia , Terapia por Exercício/métodos , CogniçãoRESUMO
Estradiol (E2) positively influences memory facilitation effects in older women and rodent models by targeting key memory-related brain regions. However, the impacts of E2 on emotional memory processes in younger women are less clear. As women are twice as likely as men to develop trauma related disorders such as posttraumatic stress disorder (PTSD), it is important to understand how hormones like E2 might impact threat memory mechanisms. Using a randomized, double-blinded, cross-over design, we administered transdermal E2 or placebo to 45 naturally-cycling, Black women (18-35 years) with a range of trauma-related symptoms during the early luteal (low endogenous E2) phase of their cycles. The following day, participants underwent a categorical threat conditioning paradigm during fMRI recording and completed a post-scan recognition test of images seen during the scanning session. The next month, participants repeated experimental procedures under the opposite patch condition. Blood samples taken day of scan showed a mean 80â¯pg/mL increase in serum E2 levels under E2 supplementation. While all participants showed an enhancement of threat on memory, such that threat-associated (CS+) images were later recognized better than neutral (CS-) pictures, neither E2 patch nor PTSD symptom severity predicted recognition performance. However, under placebo, greater bilateral entorhinal cortex (ERC) response during threat vs safety learning (CS+>CS-) was associated with greater post-scan recognition for CS+â¯compared to the CS- category, indicating greater ERC facilitation of episodic encoding and threat bias in the low E2 condition. We also found that the combination of high E2 and progesterone (P4) was associated with reduced ERC CS+â¯>CS- activity, potentially explaining why E2 supplementation did not facilitate CS+â¯>CS- recognition and suggesting an antagonistic role for P4 with E2 in memory facilitation. E2 produced an increase in ERC functional connectivity to the superior temporal gyrus during CS- encoding, which may suggest a shift in ERC engagement away from episodic encoding. These findings indicate that the post-ovulation drop in E2 and potential interactions with P4 facilitate the episodic encoding of safety and threat cues in women, given that exogenous E2 blocked these effects. This study provides novel causal evidence on the role of cyclical fluctuation in E2 in determining episodic components of memory for learned threat and safety.
Assuntos
Córtex Entorrinal , Estradiol , Medo , Memória Episódica , Humanos , Feminino , Estradiol/farmacologia , Estradiol/administração & dosagem , Estradiol/metabolismo , Estradiol/sangue , Adulto , Córtex Entorrinal/efeitos dos fármacos , Córtex Entorrinal/metabolismo , Córtex Entorrinal/fisiologia , Imageamento por Ressonância Magnética/métodos , Método Duplo-Cego , Adulto Jovem , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adolescente , Estudos Cross-Over , Medo/efeitos dos fármacos , Medo/fisiologia , Condicionamento Clássico/efeitos dos fármacosRESUMO
OBJECTIVE: While supplemental O2 corrects hypoxemia and promotes respiratory stability during sleep, its effect on post-anesthesia ventilation is unknown. Using home sleep apnea testing (HSAT) equipment, we previously found that hyperoxia improved obstructed breathing in post-anesthesia patients by primarily reducing desaturation-based hypopnea events. This trial tested the hypothesis that hyperoxia will improve disordered breathing during recovery from anesthesia, independent of oxygenation-based scoring criteria. DESIGN: Single-blinded, non-randomized-controlled, crossover trial. SETTING: University hospital. PATIENTS: 10 patients undergoing robotic-assisted laparoscopic nephrectomy. MEASUREMENTS: All patients underwent a HSAT recording during two 40-min-long interventions when inhalation of an O2/air mixture targeted an SpO2 > 96 % (Liberal O2), or an SpO2 90-94 % (Conservative O2). Continuous transcutaneous (TcPCO2) and intermittent arterial (PaCO2) measurements of CO2 were performed. Apnea/hypopnea index (AHIflow) was measured using standard criteria, except hypopneas were defined solely by standard airflow reduction without requiring associated desaturation or arousal. StanpumpR was utilized to simulate analgesic effect of administered opioids, expressed as percentage of minimum effective analgesic concentration (MEAC), which was then used to adjust the comparison between the two interventions. MAIN RESULTS: AHIflow decreased significantly from 36 ± 23 (mean ± Std) events per hour during Conservative O2, to 25 ± 17 in the Liberal O2 session (paired t-test, P = 0.0069 adjusted for the area under the MEAC-time curve). Pairwise comparisons did not show any significant difference in the TcPCO2 or PaCO2 levels between the two treatment sessions, while the percentage of time spent with TcPCO2 > 45 mmHg was also comparable between the two interventions. CONCLUSIONS: Oxygenation-independent assessment showed that hyperoxia improved disordered breathing immediately following anesthesia, primarily by decreasing the number of hypopneas. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05922020.
Assuntos
Período de Recuperação da Anestesia , Anestesia Geral , Hiperóxia , Oxigenoterapia , Síndromes da Apneia do Sono , Humanos , Estudos Cross-Over , Feminino , Masculino , Método Simples-Cego , Anestesia Geral/efeitos adversos , Anestesia Geral/métodos , Pessoa de Meia-Idade , Síndromes da Apneia do Sono/terapia , Síndromes da Apneia do Sono/etiologia , Oxigenoterapia/métodos , Idoso , Oxigênio/administração & dosagem , Oxigênio/sangue , Adulto , Procedimentos Cirúrgicos Robóticos/efeitos adversos , Procedimentos Cirúrgicos Robóticos/métodos , Laparoscopia/efeitos adversos , Laparoscopia/métodos , Saturação de OxigênioRESUMO
PURPOSE: To evaluate whether advanced footwear technology (AFT) reduces the rise in oxygen uptake (VËO2) and neuromuscular fatigue during extended submaximal running compared with traditional running shoes. METHODS: Fifteen trained distance runners (7 women, 8 men; 23.2 [1.6] y; 65.5 [7.8] kg) completed two 60-minute treadmill runs at â¼75% of critical speed, wearing either control shoes (Saucony Kinvara) or AFT (Saucony Endorphin Pro 3) in a randomized crossover design. VËO2 was measured continuously using a portable metabolic system, and ground-reaction forces were sampled at minutes 15, 30, 45, and 60. Linear regression was used to quantify VËO2 drift. Neuromuscular fatigue was assessed via changes in vertical impulse during prerun and postrun vertical jumps. RESULTS: VËO2 drift was significantly lower with AFT (0.00056 [0.00060] mL·kg-1·min-1) than with control shoes (0.00088 [0.00071] mL·kg-1·min-1; P = .018). Postrun vertical impulse decreased by only 0.2% in AFT versus 4.9% in control (P = .016), indicating reduced neuromuscular fatigue. No significant differences were found in peak force, stance time, or stride rate between conditions. CONCLUSIONS: AFT reduces the progressive increase in VËO2 and attenuates neuromuscular fatigue during extended running. These cumulative benefits may enhance endurance performance over time and highlight the importance of evaluating footwear over sustained efforts.
Assuntos
Fadiga Muscular , Consumo de Oxigênio , Corrida , Sapatos , Humanos , Fadiga Muscular/fisiologia , Corrida/fisiologia , Masculino , Consumo de Oxigênio/fisiologia , Feminino , Estudos Cross-Over , Adulto Jovem , Adulto , Teste de EsforçoRESUMO
CONTEXT: High-flow nasal therapy (HFNT) may relieve severe dyspnea, but its role compared to other treatment options in palliative care remains unclear. OBJECTIVES: Assess the effect and feasibility of HFNT with air compared to fan therapy in relieving dyspnea among nonhypoxemic patients with incurable cancer. METHODS: This prospective, randomized, controlled, crossover trial compared airflow delivered by HFNT and fan. The duration of both interventions was 30 minutes. Change in dyspnea was measured using a numeric rating scale (NRS) from 0 to 10. The overall benefits and adverse events of the interventions were assessed. (Trial identifier, NCT05257850). RESULTS: Thirty-six patients with dyspnea on NRS ≥3, and oxygen saturation ≥88% were enrolled, and 28 patients completed the trial. The median NRS for dyspnea decreased from 5.0 (interquartile range [IQR] 4.0-6.5) to 3.5 (IQR 2.0-5.8, P = 0.001) with HFNT with air and from 5.0 (IQR 4.0-7.0) to 2.5 (IQR 1.0-7.0, P = 0.012) with fan. The median change in dyspnea on NRS was -1.0 (IQR 0.0 to -2.8) for both HFNT with air and fan, with no significant difference between the therapies (P = 0.935). Over half of the patients reported that both therapies relieved their dyspnea and that they adapted well to them. CONCLUSION: The effect of airflow through HFNT or fan on dyspnea did not differ in nonhypoxemic patients with advanced cancer. Both therapies seemed to give slight relief on dyspnea without significant adverse events. Thus, the choice between HFNT with air or fan should be made according to the patient´s preferences.