Changes In Pressure Research Articles

Application of placing the anterior end of endotracheal tube at the glottis in laryngeal mask airway positive ventilation during general anesthesia: A prospective, randomized, controlled trial.

Glottic contraction and closure causes ventilation obstruction and laryngeal mask airway (LMA) leakage during positive pressure ventilation using LMA. This study aimed to assess the effect of placing the anterior end of the endotracheal tube (ET) at the glottis through the LMA ventilation conduit on treating LMA leakage following glottic contraction and closure. In this prospective, randomized, controlled trial, patients with non-minor surgery using LMA ventilation were randomly allocated to the i-gel group (group L) and the i-gel combined with ET group (group LE). The tip of ET was placed 2 cm under glottis guided by fiberoptic bronchoscope through i-gel ventilation conduit in group LE. The perioperative incidence of i-gel leakage, the changes of systolic blood pressure (SBP) and heart rate (HR) following artificial airway insertion, and adverse events were recorded. Perioperative i-gel leakage was observed in 7 of 48 patients (14.6%) in group L and 1 of 49 patients (2.0%) in group LE. There was significant difference in the incidence of leakage between the 2 groups (P = .031). SBP and HR after ET insertion in group LE increased significantly compared to those in group L (P < .05/5). The values of both SBP and HR after ET insertion did not exceed the basic values in group LE (P > .05/4). There were no significant differences in the incidence and severity of postoperative sore pain and hoarseness, cough during i-gel and ET removal between the 2 groups (P > .05). Placing the anterior end of ET at the glottis reduced LMA air leakage related to glottic contraction and closure in non-minor surgery. The ET placing had low stress response and did not significantly increase postoperative complications.

K2P2.1 channels modulate the pH- and mechanosensitivity of pancreatic stellate cells.

Pancreatic stellate cells (PSCs) are central in the development of acute pancreatitis and tumor fibrosis in pancreatic ductal adenocarcinoma (PDAC). Fibrosis and a unique pH landscape represent characteristic properties of the PDAC microenvironment. Mechanosensitive ion channels are involved in the activation of PSCs. Among these channels, K2P2.1 has not yet been studied in PSCs. K2P2.1 channels are pH- and mechanosensitive. We confirmed K2P2.1 expression in PSCs by RT-qPCR and immunofluorescence. PSCs from K2P2.1+/+ and K2P2.1-/- mice were studied under conditions mimicking properties of the PDAC microenvironment (acidic extracellular pH (pHe), ambient pressure elevated by + 100mmHg). Migration and the cell area were taken as surrogates for PSC activation and evaluated with live cell imaging. pHe-dependent changes of the membrane potential of PSCs were investigated with DiBAC4(3), a voltage-sensitive fluorescent dye. We observed a correlation between morphological activation and progressive hyperpolarization of the cells in response to changes in pHe and pressure. The effect was in part dependent on the expression of K2P2.1 channels because the membrane potential of K2P2.1+/+ PSCs was always more hyperpolarized than that of K2P2.1-/- PSCs. Cell migration velocity of K2P2.1+/+ cells decreased upon pressure application when cells were kept in an acidic medium (pHe 6.6). This was not the case in K2P2.1-/- PSCs. Taken together, our study highlights the critical role of K2P2.1 channels in the combined sensing of environmental pressure and pHe by PSCs and in coordinating cellular morphology with membrane potential dynamics. Thus, K2P2.1 channels are important mechano-sensors in murine PSCs.

Associations between Changes in Body Weight Status and High Blood Pressure among Lithuanian Children and Adolescents during the COVID-19 Pandemic: A Retrospective Cohort Study.

(1) Background: High blood pressure (HBP), overweight, and obesity are common, growing public health problems worldwide. The aim of this study was to evaluate associations between changes in body weight status and HBP among Lithuanian children and adolescents during the COVID-19 pandemic. (2) Methods: In this study, we analysed data on blood pressure and anthropometric measurements of 2430 children and adolescents aged 8-18 years, who participated in both the baseline study conducted before the COVID-19 pandemic (from November 2019 to March 2020) and the follow-up study during the COVID-19 pandemic (from November 2021 to April 2022). Multivariate logistic regression analysis was used to estimate the associations between changes in weight status categories and HBP. (3) Results: At baseline, 17.1% of the subjects had overweight, 5.9% had obesity, 5.6% had abdominal obesity, and 23.7% had HBP, whereas at the follow-up, these percentages increased to 20.1%, 8.2%, 6.8%, and 27.4%, respectively. Compared to schoolchildren who maintained normal weight from baseline to the follow-up period, subjects who newly developed overweight/obesity and those who remained with persistent overweight/obesity had increased odds of HBP, with adjusted odds ratios (aORs) of 1.95 (p < 0.001) and 2.58 (p < 0.001), respectively. In subjects who transitioned from overweight/obesity to normal weight, the odds of HBP were slightly increased, with an aOR of 1.14 (p = 0.598), but the change was not statistically significant (p > 0.05). (4) Conclusions: This study observed an increase in the prevalence of overweight, obesity, and HBP among schoolchildren during the COVID-19 pandemic. The study also suggested that changes from normal body weight status at baseline to overweight/obesity during follow-up, especially persistent overweight/obesity, were associated with higher odds of HBP in Lithuanian children and adolescents during the COVID-19 pandemic.

Cardiovascular Effects of Treatment with Atropine 0.01% Eyedrops to prevent the Progression of Childhood Myopia

The effectiveness of atropine eyedrops in preventing myopia progression in children has been confirmed, but cardiovascular effects have never been analysed. The objective of this study was to assess cardiovascular changes after treatment with atropine 0.01% eyedrops in 60 paediatric patients who were treated with atropine eyedrops due to myopic progression. Patients were analysed before treatment and 3 months after starting 1 drop daily. The parameters assessed were cardiovascular constants and electrocardiographic data. The average age was 10.2 years, with a higher women percentage. The average follow-up period was 3.5 months. No patients presented pathological electrocardiographic findings and one patient reported symptoms: palpitations. A statistically significant decrease in heart rate (79 vs. 75 bpm) was reported, but without clinical significance. No changes in blood pressure were observed. In conclusion, chronic therapy with low doses of atropine as a treatment for myopia progression does not result in pathological heart changes.

Effects of Physical Activity on Patients With Diabetes Type 2: A Systematic Review

The aim of the research was to collect and to examine the positive effects of various physical activity (PA) programs on individuals with type 2 diabetes mellitus (T2DM). This included a combination of aerobic exercises and resistance training, with varying intensities, in order to compare which approach yielded better outcomes for T2DM management; This systematic review was conducted in line with PRISMA guidelines, focusing on the period from 1991 to 2024. Studies included in this review involved both experimental procedures and questionnaire-based surveys to assess the impact of PA on T2DM patients. The primary outcome was the effect of PA on T2DM, with secondary outcomes including changes in blood pressure, cholesterol levels, and glycemic control; A total of 23 studies, encompassing 1752 participants (515 men, 546 women, and 691 unspecified), met the inclusion criteria. The studies highlighted the positive effects of exercise, such as improvements in glycemic control, insulin sensitivity, and lipid profiles. Most studies recommended a combination of aerobic and resistance exercises performed 3-4 times per week for 30-60 minutes per session; This systematic review confirms that regular PA is instrumental in managing T2DM. Health care providers should integrate PA programs into treatment plans for T2DM patients to optimize glycemic control and overall health outcomes.

Diagnosis of Abnormal Overcharge Internal Pressure in Lithium Battery Based on Physics‐Informed Neural Network's Residual Distribution

Changes in the internal pressure of lithium batteries often reflect the state of the batteries. Rapid diagnosis of abnormal internal pressure is importance for battery safety. This article proposes a battery overcharge internal pressure abnormality diagnosis method based on the detection of safety vent strain. First, this method establishes a multiphysical model between the strain of the battery's safety vent, surface temperature rise, and state of charge (SOC) under normal internal pressure. Second, a physics‐informed neural network is used to enhance the multiphysical model's accuracy. Third, the residual sequence generated from actual measurements and estimated values, along with an improved quartile range, is used to diagnose internal pressure abnormalities. Battery overcharge experiment results show that this method can diagnose internal pressure abnormalities within 260 s after overcharging and alarm. At this time, the battery has slight bulging, and the SOC is 102.1%. By conducting charging experiments under different conditions, the low false alarm rate of this method is only 0.575%. The proposed method can identify overcharging abnormalities before the lithium battery safety vent is opened, which greatly ensures the safe operation of the battery system.

In-silico characterization of a hypothetical protein of Sulfobacillus sp. hq2 for degradation of phthalate diesters

Phthalate plasticizers are hazardous compounds capable of causing endocrine disruption, cancers, and developmental disorders. Phthalate diesters are commonly used plasticizers in plastic products (PVC pipes) that leach out into the environment due to changes in temperature, pressure, and pH, posing harmful effects on different life forms. Bioremediation of phthalate diesters utilizing bacterial esterase has been recognized as an efficient approach but few effective esterases capable of degrading a wide range of phthalate diesters have been identified. Further, the thermostability of these esterases is a highly desirable property for their applications in diverse in-situ conditions. In this present in-silico study a hypothetical protein (POB10642.1) as a high-potential esterase from a thermostable strain of Sulfobacillus sp. hq2 has been characterized. Analysis revealed a significant sequence identity of 42.67 % and structural similarity (RMSD 0.557) with known phthalate diester degrading EstS1 esterase and a high Tm range of 55–66 °C. Structural analysis revealed the presence of two cavities on the surface mediating toward the catalytic site forming a catalytic tunnel. The enzyme POB10642.1 has significant molecular docking binding energies in the range of −5.4 to −7.5 kcal/mol with several phthalate diesters, including Diethyl phthalate, Dipropyl phthalate, Dibutyl phthalate, Dipentyl phthalate, Dihexyl phthalate, Benzyl butyl phthalate, Dicyclohexyl phthalate, and Bis(2-ethylhexyl) phthalate. High stability of binding during 100 ns molecular dynamics simulations revealed efficient and stable binding of the enzyme with a wide range of phthalate diesters at its active site, demonstrating the ability of the identified esterase to interact with and degrade diverse phthalate diesters. Therefore, POB10642.1 esterase can be an efficient candidate to be utilized in the development of enzyme-based bioremediation technologies to reduce the toxic levels of phthalate diesters.

Comparing E-Cigarettes and Traditional Cigarettes in Relation to Myocardial Infarction, Arrhythmias, and Sudden Cardiac Death: A Systematic Review and Meta-Analysis.

The use of electronic cigarettes (e-cigarettes) as a perceived safer alternative to traditional cigarettes has grown rapidly. However, the cardiovascular risks associated with e-cigarettes compared to regular cigarettes remain unclear. To systematically review and compare the cardiovascular outcomes of e-cigarette use versus traditional cigarette use, focusing on the risks of myocardial infarction, arrhythmias, and sudden death. A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Peer-reviewed studies published in English were included if they reported cardiovascular outcomes related to e-cigarette or traditional cigarette use. A total of 20 studies were included, covering observational and interventional studies focusing on heart rate variability, myocardial infarction, arrhythmias, and sudden cardiac events. The quality of the evidence was assessed using the GRADE criteria, and data were extracted and analyzed based on the PICOS (Population, Interventions, Comparisons, Outcomes, and Study designs) framework. The systematic review found that both e-cigarettes and traditional cigarettes pose significant cardiovascular risks, with traditional cigarettes linked to a higher incidence of myocardial infarction, arrhythmias, and sudden cardiac death. E-cigarette users also face increased risks of arrhythmias and myocardial infarction compared to non-smokers, primarily due to the constituents of aerosolized e-liquid, including nicotine and flavorings, which contribute to adverse cardiac effects. Regular e-cigarette use, particularly in combination with traditional cigarette use, was associated with a heightened risk of myocardial infarction. Studies also reported heart function abnormalities, such as systolic and diastolic dysfunction, and reduced ejection fractions. Additionally, changes in heart rate variability, heart rate, and blood pressure were observed, indicating both acute and chronic effects of e-cigarettes on cardiovascular autonomic regulation. While e-cigarettes may present a lower cardiovascular risk compared to traditional cigarettes, they are not without harm. Both products are linked to increased risks of myocardial infarction and arrhythmias, though traditional cigarettes pose a higher overall threat. Given the limitations in the current evidence base, particularly concerning the long-term effects of e-cigarette use, further research is needed to clarify these cardiovascular risks and inform public health guidelines.

Anterior Subtenon Triamcinolone Injection for Refractory Macular Edema: A Retrospective Case Series.

To evaluate the effectiveness of anterior subtenon triamcinolone (AST) injections in the management of refractory macular edema. This is a retrospective case series of consecutive eyes with refractory macular edema treated with AST at a single vitreoretinal surgeon's practice at Toronto Western Hospital, University of Toronto, Canada in 2018-2023. Refractory was defined as persistent macular edema with a central subfield thickness of 250μm or greater over a 24-week period, receiving at least four intravitreal anti-VEGF injections. Vision outcomes and optical coherence tomography features for all eyes were compared for three visits pre-AST treatment and two visits post-AST treatment. Ninety-three patients (119 eyes; diabetic macular edema (26%), and pseudophakic CME (74%), with a mean follow-up duration of 161 days were included. The presence of subretinal fluid (p=0.0013), central subfield macular thickness (p<0.0001), cube average thickness (p=0.0024) and macular cube volume (p= 0.0017) significantly improved from pre-AST to post-AST treatment. Visual acuity also significantly improved from pre-AST treatment to post-AST treatment (p<0.0001). There was no significant change in the intraocular pressures from pre-AST to post-AST (p=0.7920) and no complications were noted throughout the follow-up period. The findings from this study suggest that AST injections show modest improvement in anatomical and functional outcomes, and are safe for the treatment and management of refractory macular edema.

Hierarchical Porous Biowaste‐Based Dual Humidity/Pressure Sensor for Robotic Tactile Sensing, Sustainable Health, and Environmental Monitoring

A crucial tradeoff between material efficacy and environmental impact is often encountered in the development of high‐performance sensors. The use of rare‐earth elements or intricate fabrication techniques is sometimes needed for conventional sensing materials, posing concerns regarding sustainability. Exploring the potential of tomato peel (TP) as a dual‐purpose sensing dielectric layer for pressure and humidity monitoring is a paradigm shift, capitalizing on its porous structure and hygroscopic nature. TP‐based humidity sensor (TP‐HS) exhibits impressive results, with a wide humidity sensing range (5%–95%), fast response/recovery time (6.5/9 s), a high sensitivity (12 500 pF %RH−1), and a high stability (30 days). Additionally, TP‐based pressure sensor (TP‐PS) also shows excellent performance in accurately sensing pressure changes in a wide range (0–196 kPa). TP‐HS can easily distinguish between breathing rates (normal, fast, and slow) and moisture content present in different moisturizers (aloe vera and sanitizer) along with its successful use for proximity sensing. Alternatively, TP‐PS demonstrates weight measurement (490 and 980 N), grip recognition (measuring the pressure exerted by each finger), and gesture detection (by monitoring multiple bending angles 0°, 30°, 50°, and 80°). A wearable, biocompatible dual sensor based on a promising sustainable material for environmental, robotic, and health monitoring applications is successfully demonstrated.

Hydraulic impact of pressure transients from water conveyance tunnel on the complex hydrogeological system: A case study HPP Pirot, Serbia

Hydraulic tunnels, integral components of hydropower plant (HPP) systems, traversing diverse rock masses, pose challenges for long-term operation. The study’s main goal was to investigate how hydraulic transients originating from the headrace tunnel transfer through the concrete lining and manifest in surrounding aquifer systems. In this experimental study at the water pressure tunnel of HPP Pirot (Serbia), a novel monitoring approach was employed. The internal piezometers with highly sensitive probes are distributed strategically along the tunnel in different geological environments. This approach involved monitoring of water pressure in the surrounding rock masses and observing the impact of hydraulic transients generated by HPP operation. A comprehensive analysis of monitoring data, incorporating ordinal and partial correlations and considering geological features, provides a profound understanding of groundwater dynamics, pressure transient phenomena, and hydrogeological characterization during HPP operation. The study highlights the complex and spatially diverse hydrogeological environment, emphasizing the varying reactivity of pore pressure during HPP operation, particularly concerning Water Mass Oscillations (WMO). Reactive piezometers near the surge tank demonstrate significant pressure variations, while those located further away display synchronous pressure changes with reduced amplitudes. Schematic hydrogeological models have been created based on the hydraulic impacts of HPPs in different geological environments along the tunnel route. The water pressure response enabled aquifer characterization of (1) a thin-layered, low-fissured aquifer closely related to the reservoir, with low influence on WMO transients; (2) a low-fissured, compartment aquifer or non-aquifer with minimal to no influence on WMO transients; (3) a well-structured karst aquifer system influenced by WMO transients; (4) a fault-controlled zone of deep hypogene karst aquifer discharge highly influenced by WMO transients; and (5) an aquifer with a dominant development of the karst conduit system highly influenced by WMO transients. The study highlights the significance of monitoring water pressure within the rock mass as a fundamental element in analyzing the interaction between water pressure tunnels and the hydrogeological environment. Applying the presented instrumentation and methodology facilitates effective monitoring in research areas where pressure tunnels are constructed.

Intracranial pressure changes in traumatic brain injury patients undergoing unilateral decompressive craniectomy with dural expansion

BackgroundThe aim of this study is to assess the ICP changes induced by a unilateral fronto-temporo-parietal DC with dural expansion after moderate to severe TBI. The effect of different bone flap sizes on ICP and the neurological outcomes were also evaluated after the decompressive surgery. Methods52 TBI patients with clinical and radiological evidences of increased ICP were included in this prospective study. All patients received unilateral fronto-temporo-parietal DC with dural expansion and ventriculostomy at contralateral Kocher's point. Postoperatively, ICP values and the largest antero-posterior (AP) diameter of bone flap removed was measured, and the clinical outcomes were assessed using Extended Glasgow Outcome Scale (GOS-E) at discharge and 6 months after DC. ResultsThe median ICP significantly decreased with an average of 56.7 % reduction from the initial opening ICP. Similar ICP changes were observed in all groups. This study also found that the large bone flap group (AP diameter >15 cm) demonstrated better postoperative ICP control as compared to the small bone flap group (AP diameter 12–15 cm), although not statistically significant. The SDH and cerebral swelling groups did better in the GOS-E at 6 months after TBI compared with cerebral contusion group. ConclusionThe ICP reduction in moderate to severe TBI patients undergoing unilateral fronto-temporo-parietal DC with dural expansion occurred in accordance with decompressive steps, regardless of intracranial lesions and the surgical procedure should be performed with the bone flap size of at least 12 cm in AP diameter for adequate and sustained ICP control.

Enhanced water management in PEMFC cathode using streamlined baffles

This research investigates the impact of baffle configurations on water management within Polymer Electrolyte Membrane Fuel Cells (PEMFCs) using novel flow fields in configurations featuring staggered and parallel streamlined baffles. Utilizing the Volume of Fluid method, the two-phase flow is modeled within computational domains that encompass the flow field above the porous Catalyst and Gas Diffusion Layers. A key feature is the use of Dynamic Contact Angle model, accounting for surface tension and wall adhesion over time, which provides detailed insights into liquid water movement and pressure changes. Streamlined baffles significantly enhance water removal and reactant transport by creating circulations and increasing flow velocities. The parallel-baffle configuration demonstrated the highest water removal capability, reducing water content in flow channels by 20.08 % compared to straight channels and offering a more uniform distribution of reactants. Both baffled configurations improve performance by promoting reactant infiltration and water expulsion, but they also increase pressure drops. The parallel configuration experiences the highest pressure drop, about 4.5 times greater than the conventional straight channel, illustrating a trade-off between better water management and energy efficiency. This study provides important insights into how baffled flow field designs in PEMFCs influence flooding behavior and potentially overall performance.

Effects of field activities by age of 119 emergency response team on the blood pressure, pulse, respiration, and quality of cardiopulmonary resuscitation

This study analyzed the physical changes according to age and the quality of cardiopulmonary resuscitation through experiments by 119 EMT in transporting equipment at the first aid site and performing post-cardiopulmonary resuscitation. In all ages, cardiopulmonary resuscitation was performed without physical load and CPR was performed after moving the equipment, first, the pulse was significantly increased, and the average pulse was measured higher than in other higher age groups under the age of 30. Second, respiratory changes were significantly increased, and average breathing was measured higher than in other higher age groups when CPR was performed after wearing personal protective equipment and moving the equipment. Third, as for changes in blood pressure, all blood pressure rose, and the average blood pressure in the 40s and older was measured higher than that of the younger age. Fourth, in the quality change of cardiopulmonary resuscitation, the pressure rate was found to have a statistically significant difference in those under 30, 30 to 34, and 35 to 39 years of age, and it was measured that the speed was maintained without change in those over 40. Finally, there was a statistically significant difference in pressure depth between those under 30 and those under 35-39 years old, and the average depth was measured deeper than other higher age groups, so it is necessary to develop differentiated education and training methods at those under 30 years of relatively little experience.

Variations in Temperature and Pressure in the “Reservoir–Well” System Triggered by Blasting Recovery of Iron Ore at the Kursk Magnetic Anomaly

This paper presents the results of precise measurements of temperature and pore pressure in the “reservoir–well” system during the development of iron ore deposits of the Kursk Magnetic Anomaly (KMA) via blasting. For the observation period from October 2021 to June 2024, variations in compressibility, permeability and temperature in the upper Albian-Cenomanian confined aquifer, which is used for district water supply, were determined. The general trend in a decrease in water temperature was traced (from 12 °C to 11.4 °C). It was accompanied by an increase in the hydrostatic head (from 3.7 m to 7.4 m). Water temperature in the upper aquifer was measured for 9 industrial explosions in the mine and for 30 explosions in the quarry. For one explosion in the mine and five explosions in the quarry the coseismic changes in water temperature with amplitudes of 0.06–0.09 °C were established, while changes in pore pressure in the “reservoir–well” system were 0.4–2.2 kPa. Local changes in the permeability of the reservoir in the vicinity of the well (the skin effect) are considered to be the main factor that controls the coseismic response of temperature during industrial explosions. As the reservoir permeability increases, the water temperature in the “reservoir–well” system can decrease and vice versa. The same pattern was observed according to regime measurements performed in 2022–2023. The recorded coseismic responses of water temperature in the upper aquifer in the high-frequency range are similar to the effects observed during propagation of seismic waves originated from earthquakes in the low-frequency range at different sites all over the world for the seismic energy density of 0.05–0.45 J/m3. The observed variations in aquifer temperature in the “reservoir–well” system under episodic dynamic impacts are of particular interest from the point of view of activating hydrogeochemical processes that accompany the development of iron ore deposits.

Mechanism of barotaxis in marine zooplankton

Hydrostatic pressure is a dominant environmental cue for vertically migrating marine organisms but the physiological mechanisms of responding to pressure changes remain unclear. Here, we uncovered the cellular and circuit bases of a barokinetic response in the planktonic larva of the marine annelid Platynereis dumerilii. Increased pressure induced a rapid, graded, and adapting upward swimming response due to the faster beating of cilia in the head multiciliary band. By calcium imaging, we found that brain ciliary photoreceptors showed a graded response to pressure changes. The photoreceptors in animals mutant for ciliary opsin-1 had a smaller sensory compartment and mutant larvae showed diminished pressure responses. The ciliary photoreceptors synaptically connect to the head multiciliary band via serotonergic motoneurons. Genetic inhibition of the serotonergic cells blocked pressure-dependent increases in ciliary beating. We conclude that ciliary photoreceptors function as pressure sensors and activate ciliary beating through serotonergic signalling during barokinesis.

Mechanism of barotaxis in marine zooplankton.

Hydrostatic pressure is a dominant environmental cue for vertically migrating marine organisms but the physiological mechanisms of responding to pressure changes remain unclear. Here, we uncovered the cellular and circuit bases of a barokinetic response in the planktonic larva of the marine annelid Platynereis dumerilii. Increased pressure induced a rapid, graded, and adapting upward swimming response due to the faster beating of cilia in the head multiciliary band. By calcium imaging, we found that brain ciliary photoreceptors showed a graded response to pressure changes. The photoreceptors in animals mutant for ciliary opsin-1 had a smaller sensory compartment and mutant larvae showed diminished pressure responses. The ciliary photoreceptors synaptically connect to the head multiciliary band via serotonergic motoneurons. Genetic inhibition of the serotonergic cells blocked pressure-dependent increases in ciliary beating. We conclude that ciliary photoreceptors function as pressure sensors and activate ciliary beating through serotonergic signalling during barokinesis.

Responses to Valsalva's maneuver in spinal cord injury do not broadly relate to vasoconstrictor capacity.

A blood pressure stabilization during late phase II of Valsalva's maneuver may be utilized to confirm sympathetic vasoconstrictor control after a spinal cord injury. This study investigated whether Valsalva response was predictive of hemodynamics during tilt or isometric handgrip. Presence/absence of Valsalva response was compared to heart rate, mean arterial pressure, leg blood flow, and vascular resistance during head-up tilt and isometric handgrip to fatigue in 14 adults with spinal cord injury from C7 to T12 and 14 controls. Statistics were performed with two-way repeated measure analysis of variance (ANOVA), post hoc t-tests for between-group comparisons, and Mann-Whitney U tests for within-group. In total, six participants with spinal cord injury lacked a blood pressure stabilization for Valsalva's maneuver. However, this was not related to vasoconstrictor responses during the other tests. The groups had similar heart rate and blood pressure changes during tilt, though leg blood flow decreases and vascular resistance increases tended to be smaller at 20° tilt in those with spinal cord injury (p = 0.07 and p = 0.11, respectively). Participants with spinal cord injury had lower heart rates and markedly smaller blood pressure increases during handgrip (both p < 0.05). There were no group differences in leg blood flow, but those with spinal cord injury demonstrated a blunted vascular resistance increase by the final 10% of the handgrip (p < 0.01). Valsalva response was not consistent with hemodynamics during other stimuli, but some individuals evidence increases in sub-lesional vascular resistance to isometric handgrip comparable to controls, suggesting a sympathoexcitatory stimulus may be critical to provoke hemodynamic responses after spinal cord injury.

Bilateral adrenal artery embolization for the treatment of idiopathic hyperaldosteronism: A proof-of-principle single center study.

Unilateral adrenal artery embolization (AAE) has emerged as an alternative treatment for patients with primary aldosteronism due to aldosterone-producing adenomas or idiopathic hyperaldosteronism with bilateral adrenal hyperplasia. This study aimed to investigate the effectiveness and safety of bilateral AAE in idiopathic hyperaldosteronism. We enrolled a total of 58 patients with idiopathic hyperaldosteronism who underwent successful bilateral AAE, and 55 of them completed 6-month follow-up. Bilateral AAE significantly lowered blood pressure of patients with IHA at 1, 3, and 6 months (all P < 0.01). Six months after the procedure, office, home, and 24-hour ambulatory blood pressure decreased by 20.3/13.5, 18.4/12.6, and 13.7/9.9 mmHg, respectively. Among them, 92.7%, 90.9%, and 89.1% had significant or moderate improvement in blood pressure control at 1, 3, and 6 months after the procedure. Bilateral AAE substantially decreased plasma aldosterone levels, reversed plasma renin suppression, decreased aldosterone-to-renin ratio, and corrected hypokalemia. Importantly, the procedure did not significantly change serum cortisol and plasma adrenocorticotropic hormone (ACTH) levels, and the cortisol and ACTH circadian rhythms remained intact three months after the procedure. Additionally, 16 patients underwent ACTH stimulation tests three months post-procedure and all of them had normal results except for one with a decreased response due to exogenous steroid therapy. Flank pain was the most common side effect which happened in 96.4% of the patients and resolved within 48 h. There were no long-term side effects in the 6 months. The present study provides evidence that bilateral AAE is an effective and safe alternative treatment for patients with IHA. Changes in office and 24h ambulatory blood pressure at 1, 3, and 6 months after bilateral adrenal artery embolization in patients with idiopathic hyperaldosteronism.

A simple model incorporating foam rheology to quantify foam penetration behaviour in EPB shield tunnelling

Fulfilling the role of a soil conditioner, foam plays a pivotal role in Earth Pressure Balance (EPB) shield tunnelling by enhancing soil properties such as lowering permeability and increasing flowability. This study introduces a macro-model designed to quantify foam penetration behaviour in saturated sand, utilising rheological properties. To validate this model, experiments were conducted to replicate the foam penetration behaviour. Six sand beds characterised by varying particle sizes, along with foam having an expansion ratio of fifteen, were employed for penetration tests under different hydraulic conditions utilising a sand column device. The rheological profile of the foam is described by the power-law model, as also found by rheometer tests, although with different parameters. The flow behaviour of foam within the sand column conforms to the flow equation that governs power-law fluids in porous media. The developed model effectively predicts the foam penetration process under varying hydraulic conditions compared with the experimental results. Furthermore, the fitting results of the experimental data indicate that the flow behaviour index of the foam remains approximately 0.09 across all tests, regardless of the type of sand used. In contrast, the model-derived generalised permeability coefficient strongly correlates with the effective particle size (d10) of the sand bed. Overall, the model effectively quantifies the foam penetration behaviour, accounting for changes in infiltration velocity and pore water pressure, which is essential for understanding the transfer of support pressure in EPB shield tunnelling.