Renal vascular control during normothermia and passive heat stress does not differ between healthy younger men and women.

Men are likely at greater risk for heat-induced acute kidney injury compared with women, possibly due to differences in vascular control. We tested the hypothesis that the renal vasoconstrictor and vasodilator responses will be greater in younger women compared with men during passive heat stress. Twenty-five healthy adults [12 women (early follicular phase) and 13 men] completed two experimental visits, heat stress or normothermic time-control, assigned in a block-randomized crossover design. During heat stress, participants wore a water-perfused suit perfused with 50°C water. Core temperature was increased by ∼0.8°C in the first hour before commencing a 2-min cold pressor test (CPT). Core temperature remained clamped and at 1-h post-CPT, subjects ingested a whey protein shake (1.2 g of protein/kg body wt), and measurements were taken pre-, 75 min, and 150 min post-protein. Beat-to-beat blood pressure (Penaz method) was measured and segmental artery vascular resistance (VR, Doppler ultrasound) was calculated as segmental artery blood velocity ÷ mean arterial pressure. CPT-induced increases in segmental artery VR did not differ between trials (trial effect: P = 0.142) nor between men (heat stress: 1.5 ± 1.0 mmHg/cm/s, normothermia: 1.4 ± 1.0 mmHg/cm/s) and women (heat stress: 1.4 ± 1.2 mmHg/cm/s, normothermia: 2.1 ± 1.1 mmHg/cm/s) (group effect: P = 0.429). Reductions in segmental artery VR following oral protein loading did not differ between trials (trial effect: P = 0.080) nor between men (heat stress: -0.6 ± 0.8 mmHg/cm/s, normothermia: -0.6 ± 0.6 mmHg/cm/s) and women (heat stress: -0.5 ± 0.5 mmHg/cm/s, normothermia: -1.1 ± 0.6 mmHg/cm/s) (group effect: P = 0.204). Renal vasoconstrictor responses to the cold pressor test and vasodilator responses following an oral protein load during heat stress or normothermia do not differ between younger men and younger women in the early follicular phase of the menstrual cycle.NEW & NOTEWORTHY The mechanisms underlying greater heat-induced acute kidney injury risk in men versus women remain unknown. This study examined renal vascular control, including both vasodilatory (oral protein load) and vasoconstrictor (cold presser test) responses, during normothermia and heat stress and compared these responses between men and women. The results indicated that in both conditions neither renal vasodilatory nor vasoconstrictor responses differ between younger men and younger women.

Activation of cardiac parasympathetic and sympathetic activity occurs at different skin temperatures during face cooling.

Sufficiently cold-water temperatures (<7°C) are needed to elicit the sympathetic response to the cold pressor test using the hand. However, it is not known if stimulating the trigeminal nerve via face cooling, which increases both sympathetic and cardiac parasympathetic activity, also has a threshold temperature. We tested the hypothesis that peak autonomic activation during a progressive face cooling challenge would be achieved when the stimulus temperature is ≤7°C. Twelve healthy participants (age: 25 ± 3 yr, four women) completed our study. Six pliable bags, each containing water or an ice slurry (34°C, 28°C, 21°C, 14°C, 7°C, and 0°C) were applied sequentially to participants' forehead, eyes, and cheeks for 5 min each. Mean arterial pressure (photoplethysmography; index of sympathetic activity) and heart rhythm (3-lead ECG) were averaged in 1-min increments at the end of baseline and throughout each temperature condition. Heart rate variability in the time [(root mean square of successive differences (RMSSD)] and frequency [high-frequency (HF) power] domains was used to estimate cardiac parasympathetic activity. Data are presented as the increase from baseline ± SD. Mean arterial pressure only increased from baseline in the 7°C (13.1 ± 10.3 mmHg; P = 0.018) and 0°C (25.2 ± 7.8 mmHg; P < 0.001) conditions. Only the 0°C condition increased RMSSD (160.6 ± 208.9 ms; P = 0.009) and HF power (11,450 ± 14,555 ms2; P = 0.014) from baseline. Our data indicate that peak increases in sympathetic activity during face cooling are initiated at a higher forehead skin temperature than peak increases in cardiac parasympathetic activity.

Acute exposure to carbon monoxide inhalation and/or hot water immersion transiently increases erythropoietin in females but not in males.

The use of acute carbon monoxide inhalation (COi) and hot water immersion (HWI) are of growing interest as interventions to stimulate erythropoietin (EPO) production. However, whether EPO production is further augmented when combining these stressors and whether there are sex differences in this response are poorly understood. Therefore, we measured circulating EPO concentration in response to acute COi and HWI independently and in combination and determined whether the responses were altered by sex. Participants completed three study visits-COi, HWI, and combined COi and HWI-separated by 1 week in a randomized, balanced, crossover design. Renal blood velocity was measured during all interventions, and carboxyhaemoglobin was measured during and after COi. Serum samples were analysed every hour for 6 h post-intervention for EPO concentration. HWI decreased renal blood velocity (46.2 cm/s to 36.2 cm/s) (P < 0.0001), and COi increased carboxyhaemoglobin (1.5%-12.8%) (P < 0.0001) without changing renal blood velocity (46.4-45.2 cm/s) (P = 0.4456). All three interventions increased peak EPO concentration from baseline (COi: 6.02-9.74 mIU/mL; HWI: 6.80-11.10 mIU/mL; COi + HWI: 6.71-10.91 mIU/mL) (P = 0.0048) and to the same extent (P = 0.3505). On average, females increased EPO while males did not in response to COi (females: 6.17 mIU/mL; males: 1.27 mIU/mL) (P = 0.0010), HWI (females: 6.47 mIU/mL; males: 2.14 mIU/mL) (P = 0.0104), and COi and HWI (females: 6.65 mIU/mL; males: 1.76 mIU/mL) (P = 0.0256). These data emphasize that combining these interventions does not augment EPO secretion and that these interventions may work better in females.

Boosting efficiency in the endoscopy suite: integrating team workflows improves productivity and minimizes cost.

BACKGROUND AND AIMS: Inefficiencies in the endoscopy suite cause frustration for physicians, hospital administrators, staff, and patients. Turnover time (TOT), the time between one case ending and another beginning, is subjectively disproportionate between various team members. We aimed to define perceptions of TOT and target steps within the process to improve efficiency. METHODS: This was a prospective cohort study at a tertiary center outpatient endoscopy unit. Phase I aimed to identify the TOT process components based on time stamps in the electronic medical record (N = 686). We defined gastroenterologist perceived TOT (pTOT), anesthesia pTOT, and standard TOT (sTOT). TOT length was calculated for each subgroup. Patient transport was identified as an intervenable target. In Phase II, the task of patient transport moved from the anesthesiology team to endoscopy nurses. Mean TOT and proportion of cases with sTOT <15 minutes' preintervention (n = 2192) and postintervention (n = 292) were compared. RESULTS: Seven key TOT components were identified that explain variations in pTOT. Average anesthesia pTOT was 15 minutes, whereas average gastroenterologist pTOT was 34 minutes (25.9% vs 57.2% of case length; P = .0007). In Phase II, mean sTOT improved from 18.51 to 14.25 minutes (P < .0001), and proportion of sTOT within 15 minutes improved from 41.79% to 58.90% (P < .0001). This intervention saved 45 minutes per room per day, allowing for a revenue potential of more than $300,000 per year per procedure room. CONCLUSIONS: This study defines variations in TOT and shows that finding imbalances and sharing the workload significantly cuts costs and improves the overall efficiency of the different subgroups in the turnover process.

American Society for Gastrointestinal Endoscopy-European Society of Gastrointestinal Endoscopy guideline on primary endoscopic bariatric and metabolic therapies for adults with obesity.

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥ 30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

American Society for Gastrointestinal Endoscopy-European Society of Gastrointestinal Endoscopy guideline on primary endoscopic bariatric and metabolic therapies for adults with obesity.

This joint ASGE-ESGE guideline provides an evidence-based summary and recommendations regarding the role of endoscopic bariatric and metabolic therapies (EBMTs) in the management of obesity. The document was developed using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) framework. It evaluates the efficacy and safety of EBMT devices and procedures that currently have CE mark or FDA-clearance/approval, or that had been approved within five years of document development. The guideline suggests the use of EBMTs plus lifestyle modification in patients with a BMI of ≥30 kg/m2, or with a BMI of 27.0-29.9 kg/m2 with at least 1 obesity-related comorbidity. Furthermore, it suggests the utilization of intragastric balloons and devices for endoscopic gastric remodeling (EGR) in conjunction with lifestyle modification for this patient population.

Diagnostic accuracy of thermal, hydration, and heart rate assessments in discriminating positive acute kidney injury risk following physical work in the heat.

Occupational heat stress increases the risk of acute kidney injury (AKI). This study presents a secondary analysis to generate novel hypotheses for future studies by investigating the diagnostic accuracy of thermal, hydration, and heart rate assessments in discriminating positive AKI risk following physical work in the heat in unacclimatized individuals. Unacclimatized participants (n = 13, 3 women, age: ∼23 years) completed four trials involving 2 h of exercise in a 39.7 ± 0.6 °C, 32 ± 3% relative humidity environment that differed by experimental manipulation of hyperthermia (i.e., cooling intervention) and dehydration (i.e., water drinking). Diagnostic accuracy was assessed via receiver operating characteristic curve analysis. Positive AKI risk was identified when the product of concentrations insulin-like growth factor binding protein 7 and tissue inhibitor of metalloproteinase-2 [IGFBP7∙TIMP-2] exceeded 0.3 (ng∙mL-1)2∙1000-1. Peak absolute core temperature had the acceptable discriminatory ability (AUC = 0.71, p = 0.009), but a relatively large variance (AUC 95% CI: 0.57-0.86). Mean body temperature, urine specific gravity, urine osmolality, peak heart rate, and the peak percent of both maximum heart rate and heart rate reserve had poor discrimination (AUC = 0.66-0.69, p ≤ 0.051). Mean skin temperature, percent change in body mass and plasma volume, and serum sodium and osmolality had no discrimination (p ≥ 0.072). A peak increase in mean skin temperature of >4.7 °C had a positive likelihood ratio of 11.0 which suggests clinical significance. These data suggest that the absolute value of peak core temperature and the increase in mean skin temperature may be valuable to pursue in future studies as a biomarker for AKI risk in unacclimatized workers.

East Australian Current velocity, temperature and salinity data products.

The East Australian Current (EAC) is the complex, highly energetic western boundary current that flows along the east coast of Australia. The EAC and its associated turbulent eddies dominate the marine climate of the Coral and Tasman Seas and the eastern Australian continental shelf. Here we present a series of consistent EAC data products that combines in situ temperature, salinity and velocity observations from the Australian Integrated Marine Observing System (IMOS) and Commonwealth Scientific and Industrial Research Organisation (CSIRO) EAC mooring array and North Stradbroke Island reference site. The EAC data products are produced from over 1000 individual instrument files collected during six 18-month deployments in the East Australian Current (EAC) off Brisbane, Australia at 27 °S between 2012-2022. The mooring individual instrument files are combined, interpolated onto a common vertical, temporal (hourly and daily) and spatial grid. The ITCOMPSOM method is used to fill missing data in the time series. These data product can be used to investigate intra- and interannual EAC variability and boundary current dynamics.

The 300 Marines: characterizing the US Marines with perfect scores on their physical and combat fitness tests.

Few US Marines earn perfect 300 scores on both their Physical Fitness Test (PFT) and Combat Fitness Test (CFT). The number 300 invokes the legendary 300 Spartans that fought at the Battle of Thermopylae, which inspired high physical fitness capabilities for elite ground forces ever since. Purpose: Determine distinguishing characteristics of the "300 Marines" (perfect PFT and CFT scores) that may provide insights into the physical and physiological requirements associated with this capability. These tests have been refined over time to reflect physical capabilities associated with Marine Corps basic rifleman performance. Materials and methods: Data were analyzed from US Marines, including 497 women (age, 29 ± 7 years; height 1.63 ± 0.07 m; body mass, 67.4 ± 8.4 kg) and 1,224 men (30 ± 8 years; 1.77 ± 0.07 m; 86.1 ± 11.1 kg). Marines were grouped by whether they earned perfect 300 scores on both the PFT and CFT (300 Marines) or not. We analyzed group differences in individual fitness test events and body composition (dual-energy x-ray absorptiometry). Results: Only 2.5% (n = 43) of this sample earned perfect PFT and CFT scores (n = 21 women; n = 22 men). Compared to sex-matched peers, 300 Marines performed more pull-ups, with faster three-mile run, maneuver-under-fire, and movement-to-contact times (each p < 0.001); 300 Marines of both sexes had lower fat mass, body mass index, and percent body fat (each p < 0.001). The lower percent body fat was explained by greater lean mass (p = 0.041) but similar body mass (p = 0.085) in women, whereas men had similar lean mass (p = 0.618), but lower total body mass (p = 0.025). Conclusion: Marines earning perfect PFT and CFT scores are most distinguished from their peers by their maneuverability, suggesting speed and agility capabilities. While both sexes had considerably lower percent body fat than their peers, 300 Marine women were relatively more muscular while men were lighter.

Polymer Bioelectronics: A Solution for Both Stimulating and Recording Electrodes.

The advent of closed-loop bionics has created a demand for electrode materials that are ideal for both stimulating and recording applications. The growing complexity and diminishing size of implantable devices for neural interfaces have moved beyond what can be achieved with conventional metallic electrode materials. Polymeric electrode materials are a recent development based on polymer composites of organic conductors such as conductive polymers. These materials present exciting new opportunities in the design and fabrication of next-generation electrode arrays which can overcome the electrochemical and mechanical limitations of conventional electrode materials. This review will examine the recent developments in polymeric electrode materials, their application as stimulating and recording electrodes in bionic devices, and their impact on the development of soft, conformal, and high-density neural interfaces.

Rahnella Aquatilis Endophthalmitis after Intravitreal Injection in an Immunocompetent Patient.

PURPOSE: To present a novel case of exogenous Rahnella aquatilis endophthalmitis following an intravitreal injection. METHODS: Case report. RESULTS: A 74-year-old male presented with acute progressive vision loss and pain in the left eye, 5 days after an intravitreal injection for diabetic macular edema. The patient was diagnosed with exogenous endophthalmitis and empirically treated with intravitreal injections of vancomycin and ceftazidime as well as topical and oral ciprofloxacin. In follow up two days later, the patient was treated with preoperative povidone-iodine followed by prompt vitrectomy with additional vancomycin and ceftazidime due to pharmacy sterile hood issues that delayed antibiotic availability. Microbiological cultures and two mass spectrometry identification tests confirmed the diagnosis of exogenous Rahnella aquatilis endophthalmitis. Despite the presence of scattered retinal hemorrhagic infarcts involving the macula and subsequent full-thickness atrophic macular holes seen in follow up, the patient achieved a favorable anatomical and functional outcome of BCVA 20/80 at 1 year of follow-up. CONCLUSION: This case highlights the occurrence of exogenous Rahnella aquatilis endophthalmitis following an intravitreal injection for diabetic macular edema. Prompt diagnosis and treatment produced a favorable outcome relative to other typical Gram-negative Enterobacteriaceae organisms.

Day-to-day reliability of basal heart rate and short-term and ultra short-term heart rate variability assessment by the Equivital eq02+ LifeMonitor in US Army soldiers.

INTRODUCTION: The present study determined the (1) day-to-day reliability of basal heart rate (HR) and HR variability (HRV) measured by the Equivital eq02+ LifeMonitor and (2) agreement of ultra short-term HRV compared with short-term HRV. METHODS: Twenty-three active-duty US Army Soldiers (5 females, 18 males) completed two experimental visits separated by >48 hours with restrictions consistent with basal monitoring (eg, exercise, dietary), with measurements after supine rest at minutes 20-21 (ultra short-term) and minutes 20-25 (short-term). HRV was assessed as the SD of R-R intervals (SDNN) and the square root of the mean squared differences between consecutive R-R intervals (RMSSD). RESULTS: The day-to-day reliability (intraclass correlation coefficient (ICC)) using linear-mixed model approach was good for HR (0.849, 95% CI: 0.689 to 0.933) and RMSSD (ICC: 0.823, 95% CI: 0.623 to 0.920). SDNN had moderate day-to-day reliability with greater variation (ICC: 0.689, 95% CI: 0.428 to 0.858). The reliability of RMSSD was slightly improved when considering the effect of respiration (ICC: 0.821, 95% CI: 0.672 to 0.944). There was no bias for HR measured for 1 min versus 5 min (p=0.511). For 1 min measurements versus 5 min, there was a very modest mean bias of -4 ms for SDNN and -1 ms for RMSSD (p≤0.023). CONCLUSION: When preceded by a 20 min stabilisation period using restrictions consistent with basal monitoring and measuring respiration, military personnel can rely on the eq02+ for basal HR and RMSSD monitoring but should be more cautious using SDNN. These data also support using ultra short-term measurements when following these procedures.

Hypohydration attenuates increases in creatinine clearance to oral protein loading and the renal hemodynamic response to exercise pressor reflex.

Insufficient hydration is prevalent among free living adults. This study investigated whether hypohydration alters 1) renal functional reserve, 2) the renal hemodynamic response to the exercise pressor reflex, and 3) urine-concentrating ability during oral protein loading. In a block-randomized crossover design, 22 healthy young adults (11 females and 11 males) underwent 24-h fluid deprivation (Hypohydrated) or 24-h normal fluid consumption (Euhydrated). Renal functional reserve was assessed by oral protein loading. Renal hemodynamics during the exercise pressor reflex were assessed via Doppler ultrasound. Urine-concentrating ability was assessed via free water clearance. Creatinine clearance did not differ at 150 min postprotein consumption between conditions [Hypohydrated: 246 mL/min, 95% confidence interval (CI): 212-280; Euhydrated: 231 mL/min, 95% CI: 196-265, P = 0.2691] despite an elevated baseline in Hypohydrated (261 mL/min, 95% CI: 218-303 vs. 143 mL/min, 95% CI: 118-168, P < 0.0001). Renal artery vascular resistance was not different at baseline (P = 0.9290), but increases were attenuated in Hypohydrated versus Euhydrated at the end of handgrip (0.5 mmHg/cm/s, 95% CI: 0.4-0.7 vs. 0.8 mmHg/cm/s 95% CI: 0.6-1.1, P = 0.0203) and end occlusion (0.2 mmHg/cm/s, 95% CI: 0.1-0.3 vs. 0.4 mmHg/cm/s 95% CI: 0.3-0.6, P = 0.0127). There were no differences between conditions in free water clearance at 150 min postprotein (P = 0.3489). These data indicate that hypohydration 1) engages renal functional reserve and attenuates the ability to further increase creatinine clearance, 2) attenuates increases in renal artery vascular resistance to the exercise pressor reflex, and 3) does not further enhance nor impair urine-concentrating ability during oral protein loading.NEW & NOTEWORTHY Insufficient hydration is prevalent among free living adults. This study found that hypohydration induced by 24-h fluid deprivation engaged renal functional reserve and that oral protein loading did not further increase creatinine clearance. Hypohydration also attenuated the ability to increase renal vascular resistance during the exercise pressor reflex. In addition, hypohydration neither enhanced nor impaired urine-concentrating ability during oral protein loading. These data support the importance of mitigating hypohydration in free living adults.

Controlled electroactive release from solid-state conductive elastomer electrodes.

This work highlights the development of a conductive elastomer (CE) based electrophoretic platform that enables the transfer of charged molecules from a solid-state CE electrode directly to targeted tissues. Using an elastomer-based electrode containing poly (3,4-ethylenedioxythiophene) nanowires, controlled electrophoretic delivery of methylene blue (MB) and fluorescein (FLSC) was achieved with applied voltage. Electroactive release of positively charged MB and negatively charged FLSC achieved 33.19 ± 6.47 µg release of MB and 22.36 ± 3.05 µg release of FLSC, a 24 and 20-fold increase in comparison to inhibitory voltages over 1 h. Additionally, selective, and sequential release of the two oppositely charged molecules from a single CE device was demonstrated, showing the potential of this device to be used in multi-drug treatments.