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A framework for delivering real-time, instrument-relative navigation in transoral robotic surgery.

Transoral robotic surgery (TORS) is a minimally invasive, inside-out technique that, compared with traditional open approaches, provides fewer post-operative complications, shorter hospital stays, and improved survival for early-stage head and neck cancer. However, TORS is limited by its steep learning curve and poor visualization of deep tumor margins. This randomized crossover study evaluated a surgical navigation system's potential to enhance accuracy and user experience with real-time, instrument-relative feedback. Seven Teflon beads (d = 2.381 mm) were embedded at the tongue base of a porcine pharynx-and-larynx model. Tongue blade compression and retraction were applied to the model to mimic intraoperative tissue deformation, reproducing the anatomical shifts that occur relative to preoperative imaging. Eight participants used the da Vinci Surgical system to localize the beads by placing pins under two conditions: (a) preoperative computed tomography with no navigation; (b) model-based visual navigation with quantitative instrument-to-target metrics. Surgical accuracy was determined by calculating the target localization error (TLE, pin-to-bead Euclidean distance) and the angular error (AE, pin axis trajectory to bead). Accounting for training level and bead depth, surgical navigation reduced TLE by 5.44 mm (95% CI, 4.02-6.86 mm; p = 2.00e-11) and AE by 8.47 degrees (95% CI, 6.21-10.72 degrees; p = 5.17e-11). Impressions of the system were generally favorable using a 5-point Likert survey and task duration (p = 0.26) or cognitive workload via the NASA-Task Load Index (p = 0.22) were not significantly affected. The navigation system demonstrated translational promise, offering improved target localization accuracy and more consistent performance across experience levels, two critical determinants of surgical quality in TORS.

Robotic Surgical Procedures

Effects of adjunctive bifrontal tDCS on depressive symptoms and cognitive performance in major depressive disorder: A randomized, double-blind, sham-controlled crossover pilot study.

BACKGROUND: Evidence for antidepressant effects of transcranial direct current stimulation (tDCS) in major depressive disorder (MDD) is heterogeneous, and cognitive effects remain uncertain. We compared depressive symptoms and DSST performance during active and sham bifrontal tDCS in medicated outpatients with MDD and baseline HAMD-17 &#x2265; 15. METHODS: In this randomized, double-blind, sham-controlled crossover pilot trial, adults with MDD and inadequate response to an adequate antidepressant trial were assigned to active&#x2192;sham or sham&#x2192;active tDCS sequences while continuing antidepressants. Each period comprised 10 sessions over 2 weeks. Active stimulation was delivered at 2 mA for 20 min (anode F3, cathode F4); sham used the same montage with brief ramping only. No washout interval was used. No washout interval was used. The primary outcome was HAMD-17; secondary outcomes were DSST and CGI ratings. RESULTS: Of 38 randomized participants, 32 completed both periods and were analyzed per protocol. HAMD-17 scores were lower during active than sham stimulation (mean difference -3.63, 95% CI -5.86 to -1.40; p = 0.002), but the condition-by-sequence interaction was significant (p = 0.026). No condition effect was observed for DSST (p = 0.261) or CGI-Severity (p = 1.000); CGI-Improvement was strongly sequence-dependent (p < 0.001). In an exploratory first-period analysis, adjusted T1 HAMD-17 scores were lower in the active-first group (adjusted difference -4.90, 95% CI -7.92 to -1.87; p = 0.003). Adverse effects were mild and transient. CONCLUSIONS: Active tDCS was associated with lower HAMD-17 scores, but the pooled contrast was order-dependent and cannot be interpreted as a definitive treatment effect. No DSST benefit was observed.

Humans

Developing low-carbon metered-dose inhalers: effects of propellant HFA-152a on mucociliary clearance and bronchoconstriction in two Phase 1 randomised trials.

BACKGROUND: To reduce the impact of respiratory care on climate change, metered-dose inhalers (MDIs) are being reformulated with low-global warming potential (GWP) propellants. Next-generation propellant hydrofluoroalkane (HFA)-152a has >90% lower GWP than HFA-134a. As part of the safety evaluation for HFA-152a, mucociliary clearance (MCC), bronchoconstriction and safety were compared with HFA-134a. METHODS: Two Phase 1, randomised, two-way crossover studies (NCT06506266/NCT06702462) were conducted. MCC study: healthy participants inhaled HFA-152a and HFA-134a in two 7-day sequences. MCC was quantified as area under radiolabelled particle retention time curve over 4&#x202f;h (AUC0-4h) after nebulised 99mTc sulphur colloid, following each propellant. Bronchoconstriction study: patients with mild asthma inhaled single doses of HFA-152a and HFA-134a. Non-inferiority of HFA-152a versus HFA-134a was defined as percent change in FEV1 (litres), 15&#x202f;min post dose (95% confidence intervals [CI]: lower limit >-10%, upper limit >0%). Both studies assessed safety. RESULTS: In 22 healthy participants, the impact on MCC did not differ between HFA-134a and HFA-152a (AUC0-4h geometric mean ratio [90% CI]: 1.00 [0.99,&#xa0;1.01]). In 19 patients with mild asthma, neither HFA-152a nor HFA-134a induced bronchoconstriction (percent change in FEV1 at 15&#x202f;min: -0.37% [HFA-152a] vs -0.60% [HFA-134a]); HFA-152a was non-inferior to HFA-134a (mean difference [95% CI]: 0.23% [-3.61,&#xa0;4.07]). Adverse event (AE) rates were low and similar for both propellants in both studies; all AEs were mild, with no serious AEs or deaths. CONCLUSION: HFA-152a and HFA-134a had almost identical effects on MCC, neither induced bronchoconstriction, supporting MDI reformulation with the low-GWP propellant HFA-152a.

Humans

The effect of drysuit diving in warm water on body temperature and post immersion orthostatic hypotension.

INTRODUCTION: Warm-water diving can limit heat dissipation, particularly when performed in fully encapsulating protective gear, leading to substantial thermal and cardiovascular strain that may impair diver safety. Following immersion, removal of hydrostatic support combined with heat-induced vasodilation may reduce central blood volume and increase susceptibility to orthostatic intolerance during egress and recovery. The extent to which this thermal strain impairs post-immersion orthostatic tolerance remains unknown. METHODS: Four randomised, crossover immersion trials were conducted at 28&#xb0;C, 33&#xb0;C, 38&#xb0;C without precooling (38&#xb0;C), and 38&#xb0;C with precooling (38&#xb0;C + Cool), with subjects wearing fully encapsulating dive gear. Subjects walked for up to 60 minutes at approximately 50% of O2max heart rate (HR) or until core temperature (Tc) reached 38.5&#xb0;C, or they voluntarily stopped. Tc, HR, and perceptual measures were recorded every 10 minutes. Orthostatic tolerance was assessed after immersion via a 70&#xb0; head-up tilt test. RESULTS: Eight healthy adults completed all aspects of the study. Tc and HR were higher during both 38&#xb0;C conditions compared with 28&#xb0;C and 33&#xb0;C (all P < 0.01) with no differences between 38&#xb0;C and 38&#xb0;C + Cool. Sweat loss exceeded 1.2 (SD 0.67) L&#x22c5;h-1 in both 38&#xb0;C conditions compared with &#x2264; 0.3 (0.32) L&#x22c5;h-1 at 28&#xb0;C and 33&#xb0;C (P < 0.01). Survival analysis showed orthostatic tolerance decreased with increasing thermal stress (log-rank P = 0.027; trend P = 0.003). Precooling did not reduce peak Tc or HR, nor did it improve tolerance time in 38&#xb0;C water. CONCLUSIONS: Encapsulated warm-water diving causes heat stress and cardiovascular strain that persists after immersion, impairing orthostatic tolerance. Precooling does not significantly reduce these outcomes.

Humans

Effects of carbohydrate mouth rinse on psychophysiological responses, kinematic variables and technical actions during small-sided soccer games.

BACKGROUND: This study investigated the effects of carbohydrate mouth rinsing (CHOMR) on various psychophysiological, kinematic, and technical actions during 4-a-side small-sided soccer games (SSGs). METHODS: In a randomized, crossover, double-blind design, 16 young male soccer players (age: 15&#x2009;&#xb1;&#x2009;1 years; height: 172.6&#x2009;&#xb1;&#x2009;7.0&#x2009;cm; body mass: 57.8&#x2009;&#xb1;&#x2009;7.9 kg) participated in two 4-a-side SSGs separated by one week following either CHOMR or placebo (PLA). During each SSGs, heart rate (HRmean, %HR, and HRmax), rating of perceived exertion (RPE), enjoyment, visual analogue scale (VAS) to perceived mental fatigue, mood states, total distance (TD), high-speed running distance (HSRD), average metabolic power (AMP), high metabolic load distance (HMLD), sprint distance (SD), acceleration (ACC), deceleration (DEC), and technical actions (e.g. passing, tackling, shooting, and interceptions) were assessed. RESULTS: Compared with PLA, CHOMR resulted in significantly higher RPE (p&#x2009;=&#x2009;0.025, g&#x2009;=&#x2009;0.86) and significantly lower VAS scores (p&#x2009;=&#x2009;0.010, g&#x2009;=&#x2009;-0.71). In addition, the CHOMR condition showed significantly higher values for interceptions, successful tackles, unsuccessful tackles, unsuccessful shots, and goals (p&#x2009;<&#x2009;0.05, g&#x2009;=&#x2009;0.96-2.02), whereas block values were significantly higher in the PLA condition. There were no statistically significant differences in HRmean, %HR, HRmax, enjoyment, TD, HSRD, AMP, HMLD, SD, ACC, DEC, successful passes, unsuccessful passes, successful shots, or mood states between the conditions (p&#x2009;>&#x2009;0.05). CONCLUSION: The current study findings suggest that CHOMR may enhance selected technical actions and lower VAS scores during 4-a-side SSGs, although it was also associated with higher RPE and did not alter the kinematic responses. In conclusion, CHOMR was associated with higher RPE, lower mental fatigue, and selective improvements in technical actions, with no significant effects on kinematic variables or HR.

Humans

A prospective crossover study comparing ICCS-recommended and Palmer-adjusted filling rates in children with spina bifida.

OBJECTIVE: This study aimed to investigate whether the maximal cystometric capacity (MCC) in children with spina bifida (SB) is indeed lower, as predicted by the Palmer formula, and to evaluate the impact of different bladder filling rates on urodynamic parameters. MATERIALS AND METHODS: This prospective, randomized, two-sequence crossover-controlled study included 70 children aged 3-18 years with spina bifida under regular follow-up. In Group 1, the first two bladder fillings were performed at the ICCS-recommended rate, and the third at 75% of that rate (Palmer formula). In Group 2, the sequence was reversed. Urodynamic parameters, including maximal cystometric capacity (MCC), bladder compliance, detrusor activity, filling pressures, and detrusor leak point pressure (DLPP), were analyzed across fillings. RESULTS: Cystometric bladder capacity was lower during fillings performed at the Palmer-adjusted rate compared with those at the ICCS-recommended rate. The proportion of reduced compliance significantly decreased in Group 1 (p = 0.046) but remained unchanged in Group 2. A significant positive correlation was observed between expected bladder capacity (EBC) and measured MCC in both groups (&#x3c1; &#x2248; 0.5-0.6). The highest correlation and agreement were found in Group 1 during the third filling at the Palmer rate (ICC = 0.606). No significant intra- or intergroup differences were observed in detrusor pressure, end-filling pressure, DLPP, or overactive bladder prevalence. CONCLUSION: Bladder filling rate was associated with differences in both cystometric capacity and bladder compliance in children with spina bifida. Fillings performed according to the Palmer formula (approximately 75% of the ICCS-recommended rate) were associated with capacities that more closely approximated age-expected values and with modest differences in bladder compliance. Conversely, faster filling rates did not produce similar benefits. These findings suggest that slower filling strategies may improve measurement consistency and agreement with expected bladder capacity estimates. However, the magnitude and direct clinical impact of these differences should be interpreted cautiously, particularly in light of the potential influence of sequence-related effects.

Humans

A New Highly Concentrated Insulin Aspart AT278 (500&#x2009;U/mL) Demonstrates Ultra-Rapid Pharmacokinetic and Pharmacodynamic Properties in Type 2 Diabetes Regardless of BMI.

AIMS: To evaluate the pharmacokinetics, pharmacodynamics, and safety of a novel U500 insulin aspart formulation (AT278 [500&#x2009;U/mL]; AT278-U500) compared with standard concentration insulin aspart (InsAsp [100&#x2009;U/mL]; InsAsp-U100) and U500 human regular insulin (HumIns [500&#x2009;IU/mL]; HumIns-U500). MATERIALS AND METHODS: This single-centre, randomised, double-blind crossover 12-h euglycaemic clamp study was conducted in 41 overweight and obese people with type 2 diabetes (BMI 25.0-38.7&#x2009;kg/m2) receiving a single subcutaneous dose (0.5&#x2009;U/kg) of AT278-U500 and InsAsp-U100. HumIns-U500 was consecutively studied open label in a 24-h clamp. RESULTS: AT278-U500 exhibited a significantly faster insulin absorption than InsAsp-U100 and HumIns-U500 (t Early50%Cmax: 9&#x2009;min vs. 35&#x2009;min vs. 55&#x2009;min), leading to a significantly higher glucose-lowering effect within the first hour (AUCGIR,0-60min) compared with both InsAsp-U100 (treatment ratio 2.02 [95% CI 1.64; 2.50]) and HumIns-U500 (3.91 [2.89; 5.27]). When divided by median BMI (29.7&#x2009;kg/m2), AUCGIR,0-60min was significantly higher with AT278-U500 in both the low-BMI and high-BMI subgroup compared to InsAsp-U100. Linear regression showed a significant inverse relationship between BMI and AUCGIR,0-60min for InsAsp-U100 (slope -0.142, p&#x2009;<&#x2009;0.0001), whereas AT278-U500 showed no such relationship. Overall insulin exposure was similar for AT278-U500 and InsAsp-U100, while overall glucose-lowering effect was comparable across all three treatments. CONCLUSIONS: AT278-U500 maintains its ultra-rapid onset characteristics independent of BMI, representing the first ultra-rapid U500 option for prandial dosing in insulin-resistant people with type 2 diabetes requiring high-dose therapy. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT05754424.

Humans

Technology choice, glycemic control and patient-reported outcome measures in adults with type 1 diabetes: A randomized crossover trial comparing a smart insulin pen with an automated insulin delivery system (EBIACE-1).

AIMS: To compare glycemic outcomes and patient-reported outcome measures (PROMs) between smart insulin pens (SIP) and an automated insulin delivery (AID) system in adults with type 1 diabetes (T1D), and to identify individuals able to maintain near-optimal glycemic control using SIP. METHODS: EBIACE-1 was a randomized, open-label, crossover trial including 31 adults with T1D. Participants received SIP (InPen&#x2122;) and AID (MiniMed&#x2122; 780G) for 6&#xa0;months each. Co-primary outcomes were time in range (TIR 70-180 mg/dL) and HbA1c. Treatment effects were assessed using longitudinal models in intention-to-treat (ITT) and per-protocol (PP) analyses. Predictors of near-optimal glycemic control with SIP were evaluated using multivariable logistic regression. RESULTS: AID improved glycemic control versus SIP, with higher TIR (81&#xa0;% vs 66&#xa0;%; +15&#xa0;%, 95&#xa0;% CI 10-19; P&#xa0;<&#xa0;0.001) and lower HbA1c (6.9&#xa0;% [52&#xa0;mmol/mol] vs 7.3&#xa0;% [56&#xa0;mmol/mol]; -0.4&#xa0;%, 95&#xa0;% CI&#xa0;-&#xa0;0.6 to&#xa0;-&#xa0;0.3; P&#xa0;<&#xa0;0.001). Near-optimal glycemic control with SIP was achieved by 12 of 26 participants (46&#xa0;%). In exploratory analyses, higher baseline diabetes-related life interference was associated with a lower probability of achieving this outcome. CONCLUSIONS: AID provides superior glycemic control, although nearly half of participants achieved near-optimal control with SIP, supporting a personalized approach to technology selection.

Adult

Responsiveness of muscle mass gain to different load intensities of resistance training in older women: A randomized crossover study.

BACKGROUND: Aging is associated with progressive declines in skeletal muscle mass (SMM) and substantial interindividual variability in adaptations to resistance training (RT). However, whether training load intensity influences hypertrophic responsiveness in older adults remains unclear. OBJECTIVE: To investigate the effects of two commonly prescribed RT loading schemes (15RM and 10RM) on estimated SMM adaptations and responsiveness in older women. METHODS: Twenty-seven older women (67.7&#xa0;&#xb1;&#xa0;4.9&#xa0;years; 65.7&#xa0;&#xb1;&#xa0;10.6&#xa0;kg; 154.5&#xa0;&#xb1;&#xa0;5.8&#xa0;cm) completed two 8-week RT interventions performed at 15RM and 10RM in a randomized crossover design, separated by a 12-week detraining period. Estimated SMM was assessed using dual-energy X-ray absorptiometry. Responsiveness was operationally defined using the standard error of measurement, and participants were classified as responders (RP) or non-responders (N-RP) according to changes in estimated SMM. RESULTS: Both loading schemes promoted significant and comparable increases in estimated SMM (15RM: +0.62&#xa0;&#xb1;&#xa0;0.4&#xa0;kg vs. 10RM: +0.43&#xa0;&#xb1;&#xa0;0.3&#xa0;kg). Overall, 61.1% of participants were classified as responders in at least one condition, whereas 38.9% were classified as non-responders. Responsiveness status was consistent across conditions for most participants, with 48.1% classified as responders under both loading schemes and 25.9% as non-responders under both conditions. Only seven participants (25.9%) changed responsiveness status between interventions. No clear pattern indicated a greater likelihood of responsiveness with either loading scheme. CONCLUSIONS: Results suggest that both the 10RM and 15RM RT protocols significantly increase estimated SMM in older women, with no significant differences between training conditions. Although substantial interindividual variability in adaptive responses exists, training load intensity does not appear to meaningfully influence responsiveness status in most individuals. These findings suggest that both loading schemes can be effectively prescribed to promote SMM gains in older women.

Aged

Comfort and Usability of Digital Versus Conventional Custom-Fit Mouthguards: A Randomized Clinical Trial.

BACKGROUND/OBJECTIVES: The use of mouthguards protects teeth and the supporting tissues against impacts. Digital impressions and 3D-printed models can reduce manufacturing steps and minimize discomfort. This study evaluated the fit, comfort, and usability of custom-made mouthguards, obtained by conventional and digital workflow, in amateur athletes. MATERIALS AND METHODS: Amateur athletes were recruited for this randomized, double-blind, crossover clinical study. Each participant received two 4-mm-thick custom-fit mouthguards made of ethylene vinyl acetate (EVA) sheets using two protocols: conventional impression using alginate to produce dental stone cast (CMP) and intraoral digital scanning to produce 3D-printed resin models (DMP). Each mouthguard was worn during all training and matches over 3&#x2009;months. The order of mouthguard use was randomly assigned. Patient satisfaction with the impression protocol and mouthguard use, model accuracy, and mouthguard fit were assessed. RESULTS: Overall, 46 participants completed the study. The DMP protocol required less execution time (p&#x2009;=&#x2009;0.023), caused less discomfort (p&#x2009;=&#x2009;0.018), anxiety (p&#x2009;=&#x2009;0.008), nausea (p&#x2009;=&#x2009;0.027), difficulty breathing (p&#x2009;<&#x2009;0.001), and unpleasant taste (p&#x2009;=&#x2009;0.006) compared to the CMP protocol. The pain (p&#x2009;=&#x2009;0.971) perceived by the participants was similar in both impression protocols. The CMP-mouthguards were considered to be better fitting by the majority of participants (p&#x2009;=&#x2009;0.027). Between-group comparisons revealed that DMP-mouthguard caused less discomfort immediately postadaptation (p&#x2009;=&#x2009;0.034), with no significant differences observed at 30 or 90&#x2009;days. CONCLUSIONS: The digital workflow demonstrated to be efficient in the fabrication of mouthguards. Digital impression was more comfortable, requiring less execution time, with more accurate printed models and produced mouthguards with reported comfort and fit levels similar to those manufactured conventionally.

Humans

The impact of acute sleep fragmentation on muscle blood flow responses to handgrip exercise.

Sleep fragmentation is reported to impair resting vascular function. The aim of this study was to test the hypothesis that acute sleep fragmentation would impair muscle blood flow during exercise. Twenty adults (10 females and 10 males) participated in a randomized crossover study that included one night of habitual sleep and one night of fragmented sleep. Sleep was assessed at home using wrist actigraphy. Arousals from sleep were increased by an audio alarm sounding every 30 min. The morning following each sleep condition, participants performed single handgrip contractions and rhythmic handgrip exercise at 15%, 30%, and 45% MVC. Forearm blood flow (FBF) was measured using Doppler ultrasound. Nightly awakenings and wake after sleep onset significantly increased by 18% and 43%, respectively, after fragmented sleep, leading to lower sleep duration (P < 0.001). Peak FBF and total hyperemic responses following single contractions were similar between sleep conditions (all P > 0.05). During rhythmic handgrip exercise, brachial artery dilation was reduced after fragmented sleep (main effect: 5.5 &#xb1; 4.8 vs. 3.3 &#xb1; 3.7%; P = 0.01), leading to a lower FBF response to rhythmic exercise (main effect: 122 &#xb1; 58 vs. 110 &#xb1; 56 mL/min; P = 0.04). Endothelial sensitivity to shear rate was similar between sleep conditions (habitual vs. fragmented: 0.039 &#xb1; 0.024 vs. 0.042 &#xb1; 0.031%/s-1; P = 0.77). In summary, acute sleep fragmentation decreases skeletal muscle blood flow during exercise. This finding suggests that blunted oxygen delivery may be a contributing factor for exercise performance deficits after disturbed sleep.NEW & NOTEWORTHY We demonstrate that one night of fragmented sleep decreases steady-state blood flow and vascular conductance during low- to moderate-intensity handgrip exercise. This impairment was not due to an impaired rapid vasodilation to single contractions nor altered endothelial sensitivity to shear rate as these variables were unchanged after acute sleep fragmentation. These results reveal a negative impact of disrupted sleep on the steady-state muscle vasodilatory response to rhythmic contractions.

Humans

A study on the differences in recovery effects of different types of nutritional supplements on competitive performance of esports athletes under mental fatigue.

BACKGROUND: To compare the effects of different nutritional supplements on the recovery of core competitive performance abilities in esports athletes following mental fatigue and to observe changes in the autonomic nervous system during recovery after nutritional supplementation by monitoring heart rate variability (HRV). METHODS: A randomized crossover within-subject controlled experimental design was adopted, including nutritional supplement type (caffeine, nitrate, Ginkgo biloba extract, catechins, placebo)&#x2009;&#xd7;&#x2009;mental fatigue state (initial, fatigued, post-supplementation). Twenty high-level first-person shooter (FPS) esports athletes were recruited. Mental fatigue was induced using a Stroop task. After ingesting the different supplements and resting for 60&#x2009;minutes, the participants completed assessments of shooting accuracy, shooting stability, spatial localization, and multitasking ability using the KovaaK's simulation trainer. HRV indices were also recorded to evaluate changes in autonomic regulation. RESULTS: For shooting accuracy, compared with the placebo condition, all four supplements significantly improved shooting accuracy scores following mental fatigue (all p&#x2009;<&#x2009;0.05); however, no significant differences were observed among the effects of the different supplements. For shooting stability, caffeine, nitrate, and catechins produced significant recovery effects on shooting stability (all p&#x2009; <&#x2009;0.05); however, no significant differences were observed among the effects of these three supplements. For spatial localization and multitasking ability, the improvements in these two abilities in the post-supplementation state may have resulted from natural recovery, and none of the four nutritional supplements demonstrated a significant recovery effect. The HRV results showed that indices including RMSSD and SDNN changed under some supplement conditions. CONCLUSIONS: Mental fatigue significantly reduced the competitive performance of esports athletes. Four types of nutritional supplements all promoted the recovery of shooting accuracy, while caffeine, nitrate, and catechins promoted the recovery of shooting stability. However, no additional recovery advantages of the nutritional supplements over placebo were identified for spatial localization or multitasking ability. Changes in HRV may reflect changes in autonomic regulation during recovery, but further research is still warranted.

Humans

Premeal insulin administration lowers postprandial blood glucose and increases myocardial microvascular blood flow in people with type 1 diabetes: a randomised, crossover clinical trial.

AIMS/HYPOTHESIS: We aimed to evaluate whether prandial insulin timing affects vascular function in people with type 1 diabetes. Our hypothesis was that premeal insulin administration would lead to greater myocardial microvascular blood flow (MBF) via blunting postprandial hyperglycaemia. METHODS: People with type 1 diabetes between 18 and 35 years of age with BMI <30 kg/m2 underwent two protocols with a 1:1 randomised crossover design wherein prandial insulin was injected either 15 min before or 15 min after meal intake began. To provide a physiological comparison, age-, sex- and BMI-matched control participants completed one study where they consumed the same meal but received no exogenous insulin. Glucose, insulin, vascular function (including ultrasound measures of myocardial and skeletal muscle microvascular perfusion, aortic stiffness, brachial artery endothelial function) and biomarkers of systemic inflammation and endothelial dysfunction were assessed at baseline and then 2 h after meal ingestion within each protocol. The primary outcome was change in myocardial MBF within each protocol. Study personnel assessing outcomes were masked to group assignment. RESULTS: Eighteen people with type 1 diabetes and 18 matched control participants were analysed within each protocol. Glucose area under the curve was significantly greater (p=0.015) in the postmeal insulin study compared with the premeal insulin study in participants with type 1 diabetes. Myocardial microvascular flow velocity significantly increased (p=0.031) with premeal insulin administration in people with type 1 diabetes and this consequently led to greater myocardial MBF (p=0.044). There were no changes in myocardial MBF within the other protocols. Changes in vital signs were similar between all protocols. CONCLUSIONS/INTERPRETATION: Appropriately timed premeal insulin led to lower postprandial blood glucose along with increased myocardial MBF in people with type 1 diabetes. Further work is needed to determine the underlying aetiology of these changes. TRIAL REGISTRATION: ClinicalTrials.gov NCT04730882.

Humans

Public health, public protest: The role of health burdens and healthcare access in protest mobilisation.

Health and politics are intertwined, yet few studies have examined the association between health and protest. This study examined whether population health burdens were associated with protest incidence and whether healthcare access modified these associations. Analysis was based on an unbalanced 2004-2023 country-year panel, combining protest counts from ACLED with rates for 22 GBD causes. Mixed-effects negative-binomial models estimated incidence-rate ratios (IRRs) with interactions for healthcare access (&#xb1;1 SD). Two-way fixed-effects Poisson models were estimated as a benchmark to distinguish cross-national associations from within-country dynamics. Health burdens were systematically, but heterogeneously, associated with protest. Rates for several non-communicable burdens were associated with protest, notably musculoskeletal disorders (IRR 1.72, 95% CI 1.37-2.15), neoplasms (1.24, 1.06-1.44), substance-use disorders (1.32, 1.12-1.56) and HIV/AIDS and other STIs (1.24, 1.12-1.38). Higher healthcare access generally attenuated health-protest associations. Fixed-effects models confirmed several associations (e.g. HIV/AIDS, neoplasms) but revealed that others (e.g. maternal/neonatal disorders, enteric infections) were driven primarily by cross-national differences. Population health burdens were associated with cross-national variation in protest mobilisation. Chronic, non-communicable burdens were associated with heightened protest, whereas poverty-linked and early-life burdens were associated with lower mobilisation. Healthcare access was associated with attenuation of these relationships.

Humans

An expanded breakfast buffet increases daily energy and protein intakes in hospitalised patients: A prospective crossover quality improvement study.

BACKGROUND & AIMS: Inadequate dietary intake remains common during hospitalisation. Ordinary hospital meals are central to nutritional intake, but their contribution depends on what is offered and what patients are able and willing to eat. We evaluated whether a preference-informed, limited expansion of the hospital breakfast buffet could increase total daily energy and protein intakes. METHODS: This prospectively structured, ward-based crossover quality-improvement study was conducted in seven inpatient wards at a tertiary university hospital. Each ward was observed for four consecutive days and randomly allocated to begin with standard or expanded breakfast, after which conditions alternated daily. The expanded buffet consisted of standard breakfast supplemented with familiar energy- and protein-rich foods selected from previous patient-choice data. Twenty-four-hour intake was registered using component-level weighed food records during the day and nursing registration overnight. Primary outcomes were total daily energy and protein intakes. Linear mixed-effects models adjusted for observation day and ward-level starting sequence and accounted for repeated patient observations and ward-level clustering. Analyses used data from patients who consumed breakfast and contributed analysable observations under both breakfast conditions. RESULTS: The primary crossover population included 71 patients contributing 188 analysable patient-days. Compared with standard breakfast, the expanded breakfast increased total daily energy intake by +198 kcal/day (95% CI 44 to 352) and protein intake by +6.8 g/day (95% CI 1.0 to 12.5), without a statistically significant increase in total food weight. Daily energy and protein adequacy increased by +8.7 and + 6.8 percentage points, respectively. The increase was driven mainly by breakfast intake, with no measurable reduction in non-breakfast intake. CONCLUSIONS: A limited expansion of the ordinary hospital breakfast buffet increased total daily energy and protein intakes in the primary crossover population of hospitalised adults who consumed breakfast. This increase occurred without a statistically significant increase in total food weight or a measurable reduction in non-breakfast intake. Small, preference-informed additions of familiar energy- and protein-rich foods at breakfast may improve daily intake by increasing the nutrient yield of foods patients are able or willing to eat.

Humans

Impact of PerioperAtive LidocAine Infusions on Enhanced Recovery After Noncardiac Surgery (IMPALA-ERAS) in an inpatient setting: rationale, design and protocol for a sequential, repeated crossover trial.

INTRODUCTION: Multimodal analgesic strategies designed to minimise perioperative opioid exposure are fundamental components of enhanced recovery after surgery (ERAS) pathways. Despite widespread implementation of ERAS protocols, the optimal analgesic regimen remains undefined, as the individual contributions of specific agents to overall analgesic efficacy and opioid-sparing effects are not fully elucidated. Intravenous lidocaine, a widely utilised local anaesthetic, possesses both analgesic and anti-inflammatory properties and has been associated with improved gastrointestinal recovery. This study seeks to pragmatically evaluate the impact of incorporating perioperative intravenous lidocaine infusion into established ERAS pathways on postoperative functional recovery. METHODS AND ANALYSIS: The Impact of PerioperAtive LidocAine Infusions (IMPALA) on ERAS trial is a single-centre, pragmatic, cluster-randomised, double-blinded, placebo-controlled study. A total of 2290 patients undergoing elective colorectal surgery, emergency general surgery, urology, ventral hernia repair, surgical oncology or spine surgery will be randomly assigned to receive either intraoperative and postoperative intravenous lidocaine infusions (administered for up to 48 hours) or placebo as part of a standardised multimodal analgesic regimen integrated into established ERAS pathways. The primary outcome is case mix index-adjusted resource length of stay, defined as the time interval from surgical initiation to hospital discharge adjusted for case mix index. The primary outcome is total inpatient opioid consumption within the first 72 hours, reported in oral morphine milligram equivalents. Secondary outcomes include various in-hospital clinical endpoints derived from the electronic health record. ETHICS AND DISSEMINATION: This protocol and accompanying statistical analysis plan outline the study design, primary and secondary endpoints and analytic methodology. The IMPALA-ERAS trial has received ethical approval from the Vanderbilt University Institutional Review Board (IRB: 250617). The findings will be disseminated via peer-reviewed publications and presentations at national conferences. Results from this trial are expected to inform evidence-based practices regarding perioperative lidocaine infusion and its potential contributions to enhanced postoperative recovery in surgical patients. TRIAL REGISTRATION NUMBER: NCT07224711.

Humans

Effects of an actuated ankle exoskeleton on walking stability in healthy adults: a controlled laboratory study.

BACKGROUND: Ankle exoskeletons are widely used to reduce the metabolic cost of walking, yet their effects on walking stability during unperturbed gait remain insufficiently understood. Walking stability can be characterized using complementary measures that capture stride-to-stride variability, global temporal organization, and local dynamic stability. Understanding how walking with an actuated ankle exoskeleton system influences these different aspects of gait stability is essential for the safe design and control of wearable robotic devices. METHODS: Eighteen healthy adults walked on a treadmill at a constant speed (1.1&#xa0;m/s) with and without an actuated bilateral ankle exoskeleton in a randomized crossover design. Spatiotemporal variability was quantified using coefficients of variation (CoV) of stride length, step width, and stance ratio. Global gait stability was assessed using detrended fluctuation analysis of stride time. Local dynamic stability was evaluated using maximum Lyapunov exponent calculated for the trunk, hip, upper leg, lower leg, and foot. Paired-samples two-sided t-tests were used to compare conditions. RESULTS: Walking with the ankle exoskeleton resulted in increased stride-to-stride spatiotemporal variability, reflected by higher CoV values for stride length (p&#x2009;<&#x2009;0.001) and stance ratio (p&#x2009;=&#x2009;0.005), while mean stride length and step width remained unchanged. Mean stance ratio was reduced in the exoskeleton condition (p&#x2009;<&#x2009;0.001). Global gait stability did not differ between conditions, indicating preserved long-range temporal gait organization. Local dynamic stability increased at the lower leg (p&#x2009;<&#x2009;0.001) and foot (p&#x2009;=&#x2009;0.019) when walking with the exoskeleton. CONCLUSIONS: Walking with the actuated ankle exoskeleton alters gait control across multiple levels during steady walking. While stride-to-stride variability in stride length and stance ratio increased, global gait stability remained unchanged. Local dynamic stability was increased at the lower leg and foot, suggesting segment-specific effects of ankle-level assistance close to the assisted joint. However, these findings should be interpreted as the combined effect of wearing the exoskeleton and receiving active assistance, rather than the isolated effect of plantarflexion assistance. These&#xa0;results provide insight for the design and control of ankle exoskeletons with respect to stability-related effects during walking.

Humans

Application of 13C MRS demonstrates carbohydrate feeding spares muscle but not liver glycogen utilization during high-intensity interval exercise.

We examined liver and muscle glycogen utilization during high-intensity interval cycling, and the impact of carbohydrate (CHO) feeding, using noninvasive 13C magnetic resonance spectroscopy (MRS). Following 24 h of standardized dietary intake, nine male cyclists completed 8 &#xd7; 5-min intervals (1-min recovery), ingesting either placebo (PLA), 60 g maltodextrin (CHO), or 60 g maltodextrin plus caffeine, taurine, l-theanine, l-citrulline, and citicoline (CHO+) in a randomized crossover design. 13C MRS and 1H imaging were performed pre- and postexercise to determine liver and muscle glycogen and liver volume, respectively. Liver glycogen utilization was not significantly different between trials (P = 0.101) despite lower postexercise plasma glucagon concentrations in CHO and CHO+ (P = 0.001). In contrast, muscle glycogen utilization was significantly lower (&#x223c;40%) with CHO feeding compared with PLA (P = 0.006), yet this sparing effect was not evident with CHO+ (P = 0.073) in accordance with a higher mean power output during the late intervals (+2.8%, P = 0.046). Plasma glucose was comparable between trials (P = 0.175), whereas plasma lactate was higher in CHO+ versus CHO (P = 0.003), alongside lower blood bicarbonate (P = 0.005), base excess (P < 0.001), and total CO2 (P = 0.004). These findings demonstrate preferential use of skeletal muscle glycogen during high-intensity interval training (HIIT), which is attenuated under conditions of CHO feeding. This sparing effect is, however, not evident with the coingestion of a caffeine-containing multi-ingredient blend, potentially due to an increased capacity to sustain higher power outputs resulting in greater glycogen utilization.NEW & NOTEWORTHY Using 13C MRS, we provide data demonstrating preferential use of skeletal muscle glycogen during HIIT. Furthermore, data show muscle glycogen utilization is attenuated with CHO feeding, yet sparing is not evident when coingesting a caffeine-containing formulation, potentially reflecting increased capacity to perform more total work rather than a direct metabolic effect of caffeine. In contrast, liver glycogen utilization was not significantly different with CHO feeding despite a modest reduction of &#x223c;5 g versus placebo.

Male