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BACKGROUND: Prostaglandin E1 (PGE1) has been shown to play a regulatory role in vasodilatation, inflammation, and leukocyte migration and adhesion, but its effects on spinal cord microcirculation after traumatic spinal cord injury (SCI) remain poorly understood. OBJECTIVE: To investigate the mechanism underlying the protective effects of PGE1 administered during the acute phase of traumatic SCI in rats on the regulation of vascular-related factors and microcirculatory function. METHODS: Seventy-two female Sprague-Dawley rats were divided into three groups (n=24 per group): control group, SCI group, and PGE1 group. An in vivo SCI model was established using Allen’s blow method. Rats in the PGE1 group were injected with PGE1 (10 μg/kg) via the tail vein immediately after SCI. Spinal cord microcirculatory blood flow and oxygen saturation, spinal cord microvessel diameter and area, spinal cord water content, vascular function regulators (von Willebrand factor, thromboxane A2, prostacyclin, endothelin-1), and inflammatory factors (tumor necrosis factor-α, interleukin-1β) were measured at 2 and 24 hours after SCI. RESULTS AND CONCLUSION: At 2 hours after SCI, the diameter and area of spinal cord microvessels, spinal cord microcirculatory blood flow, and oxygen saturation in the PGE1 group were higher than those in the SCI group (P < 0.05), the water content of the spinal cord was lower than that in the SCI group (P < 0.05), and the level of plasma von Willebrand Factor, the ratio of thromboxane A2/prostacyclin of the spinal cord and the level of endothelin-1 were lower than those in the SCI group (P < 0.05). At 24 hours after SCI, the spinal cord microvessel area, blood flow, and oxygen saturation of rats in the PGE1 group were higher than those in the SCI group (P < 0.05), the spinal cord water content was lower than that in the SCI group (P < 0.05), and the levels of plasma von Willebrand factor, spinal cord tissue thromboxane A2/prostacyclin ratio and the levels of endothelin-1, tumor necrosis factor-α and interleukin-1β were lower than those in the SCI group (P < 0.05). The diameter and area of spinal cord microvessels, spinal cord microcirculatory blood flow and blood oxygen saturation of rats in the SCI group were higher than those in the SCI group at 24 hours post-injury (P < 0.05), and the levels of plasma von Willebrand factor, spinal tissue thromboxane A2/prostacyclin ratio, tumor necrosis factor-α and interleukin-1β were higher than those at 2 hours post-injury (P < 0.05), but the level of endothelin-1 in spinal cord tissue was lower than that at 2 hours (P < 0.05). The blood flow and oxygen saturation of spinal cord microcirculation in the PGE1 group rats at 24 hours post-injury were lower than those at 2 hours post-injury (P < 0.05), and the diameter and area of spinal cord microvessels and water content of the spinal cord were higher than those at 2 hours post-injury (P < 0.05). The above results indicate that intravenous administration of PGE1 in SCI rats immediately after injury can regulate vascular function regulators, inflammatory factors and improve microcirculation of the spinal cord after SCI, which provides a potential basis for the search of drugs for the treatment of acute SCI. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) poisoning is one of the most common causes of injury and death from poisoning. The primary objective of therapy is to eliminate CO from the patient as quickly as possible to prevent acute and long-term effects. The ideal treatment is hyperbaric oxygen in a pressure chamber. However, pressure chambers are scarce, and therefore, the most common treatment is normobaric oxygen (NBO), which, however, has limited efficacy. Here, we present a full-scale batch system for extracorporeal hyperoxygenation therapy (EHT), which facilitates CO elimination extracorporeally by increasing the dissolved oxygen concentration in the blood. The EHT was characterized in vitro, resulting in a minimum carboxyhemoglobin half-life of 3.26 ± 0.11 min. In large animal trials the EHT reduced the median carboxyhemoglobin half-life by 42% (29.77 min EHT vs. 70.8 min control (NBO)). However, the EHT also induced oscillations in hemodynamic pressures due to changes in the animals' circulatory volume during operation. After optimization, the EHT could be a promising option for treating CO poisoning. [ABSTRACT FROM AUTHOR]

Background: The efficacy of high-flow nasal oxygenation (HFNO) in improving oxygenation is influenced by several factors, and its effectiveness is not always guaranteed. Therefore, we aimed to compare the effects of HFNO and standard low-flow nasal oxygenation during rigid bronchoscopy in the apneic patients. Methods: All patients were administered general anesthesia with full muscle relaxation and were randomly assigned to receive either HFNO (HFNO group) or standard low-flow oxygenation (Standard group). The study endpoints included the lowest peripheral oxygen saturation (SpO2), hypoxemia-related surgical interruptions (SpO2 ≤ 94%), and changes in arterial oxygen tension (PaO2) and carbon dioxide tension (PaCO2) during the apnea period for rigid bronchoscopy. Results: A total of 53 patients completed the study. No significant differences were found between the HFNO and the Standard groups in the lowest SpO2 levels (median [Q1, Q3]; 99 [98, 100]% vs. 98 [94, 100]%, P = 0.059) and in the increase rate of PaCO2 (mean ± standard deviation [SD]; 1.6 ± 0.7 mmHg/min vs. 2.0 ± 0.8 mmHg/min, P = 0.064). However, the HFNO group had fewer patients with hypoxemia-related surgical interruptions than the Standard group (1 [3.8%] vs. 8 [29.6%], P = 0.024) and exhibited an attenuated decline rate in PaO2 (median [Q1, Q3]: 4.6 [0.0, 7.9] mmHg/min vs. 10.5 [6.4, 12.9] mmHg/min, P = 0.005). Conclusions: While HFNO did not enhance the lowest SpO2 levels in comparison with standard low-flow oxygenation, it did reduce hypoxemia-related surgical interruptions with an attenuated decline in PaO2. Therefore, HFNO has considerable clinical efficacy for rigid bronchoscopy. [ABSTRACT FROM AUTHOR]

The Oyashio region east of northern Japan has experienced frequent marine heatwaves (MHWs) since 2010, and in the summer and fall of 2022, sea surface temperature hit a record high as of that year. This study examined the impact of the 2022/23 MHW on dissolved oxygen (DO) by analyzing observations from a vessel and biogeochemical Argo floats. It was found that warm saline water from the Kuroshio Current intruded at ~ 42°N in July. DO anomalies from the climatology above a depth of 200 m were negatively correlated with the temperature anomalies at the same depth, while the opposite was true for deeper depths. In the density coordinate, DO and temperature anomalies exhibited a strong negative correlation when the potential density (σθ) was less than ~ 27.0 kg m−3. Thus, it was demonstrated that subsurface DO anomalies could be statistically predicted from temperature and salinity fields using this relationship. Notably, DO anomalies could be divided into components related to isopycnal mixing and density-surface heaving. This decomposition revealed a dynamical process, whereby the intrusion of the Kuroshio water, which is lighter than the Oyashio water, pushed down the density surfaces, causing oxygenation. Meanwhile, isopycnal mixing tended to mitigate the increase of DO concentration since DO concentration was smaller in the south than in the north on an isopycnal surface of σθ < 27.0 kg m−3. This study clarified that, during the 2022/23 MHW, deoxygenation occurred near the surface owing the warming, whereas the DO concentration increased in the subsurface layer. [ABSTRACT FROM AUTHOR]

Functional magnetic resonance imaging (fMRI) has dramatically advanced non-invasive human brain mapping and decoding. Functional near-infrared spectroscopy (fNIRS) and high-density diffuse optical tomography (HD-DOT) non-invasively measure blood oxygen fluctuations related to brain activity, like fMRI, at the brain surface, using more-lightweight equipment that circumvents ergonomic and logistical limitations of fMRI. HD-DOT grids have smaller inter-optode spacing (~ 13 mm) than sparse fNIRS (~ 30 mm) and therefore provide higher image quality, with spatial resolution ~ 1/2 that of fMRI, when using the several source-detector distances (13–40 mm) afforded by the HD-DOT grid. Herein, simulations indicated reducing inter-optode spacing to 6.5 mm, creating a higher-density grid with more source-detector distances, would further improve image quality and noise-resolution tradeoff, with diminishing returns below 6.5 mm. We then constructed an ultra-high-density DOT system (6.5-mm spacing) with 140 dB dynamic range that imaged stimulus-evoked activations with 30–50% higher spatial resolution and repeatable multi-focal activity with excellent agreement with participant-matched fMRI. Further, this system decoded visual stimulus position with 19–35% lower error than previous HD-DOT, throughout occipital cortex. [ABSTRACT FROM AUTHOR]

Background: Early and continuous exposure to painful stimuli in premature infants leads to short-and long-term complications. Listening to white noise is an accessible and inexpensive non-invasive method that can be used as a safe nursing intervention in hospitals. This study aimed to assess white noise's effect on premature Infants' physiological parameters during peripheral intravenous catheter insertion. Methods: The present experimental study was conducted on 40 premature Infants. From 5 min before Indwelling catheters to 10 min after, white noise was played through headphones to infants at a controlled volume in the test group. Using a monitor, physiological parameters were recorded from 10 min before to 30 min after the Indwelling catheter. Statistical analysis was done through the SPSS version 27 software program. Results: Regarding respiratory rate, there was no statistically significant difference between the two groups in the first, second, and sixth stages (p < 0.05). However, in the third, fourth, and fifth stages, RR in the control group was significantly higher than the test group (p ≤ 0.05). In terms of mean arterial blood pressure, there was no statistically significant difference between the two groups in any of the stages (p < 0.05). In terms of heart rate, there was no statistically significant difference between the two groups in the first, second, and sixth stages (p < 0.05). However, in the third, fourth, and fifth stages, HR in the control group was significantly higher than the test group (p ≤ 0.05). Regarding oxygen saturation percentage, there was no statistically significant difference between the two groups in the first, second, third, and sixth stages (p < 0.05). In contrast, in the fourth and fifth stages, the oxygen saturation percentage in the test group was significantly higher than in the control group (p < 0.05). Conclusions: Although in both groups the painful procedure led to an increase in physiological variables (respiratory rate, heart rate, mean arterial blood pressure) and a decrease in blood oxygen saturation, in the test group these variables approached their initial state more quickly within half an hour after exposure to white noise. This confirms that the effect of white noise on the improvement of physiological variables is gradual. Clinical trial number: Not applicable. [ABSTRACT FROM AUTHOR]

Restoration of independent walking ability is the primary objective of stroke rehabilitation; however, not all patients achieve this goal due to diverse impairments in the paretic lower limb and compensatory mechanisms that lead to an asymmetrical and mechanically inefficient gait. This investigation aimed to examine alterations in cortical activation in post-stroke patients while walking with a wearable two-channel functional electrical stimulation (FES) in comparison to walking without FES. This observational study was conducted to discern distinct activation patterns in 19 stroke patients during sessions with and without FES, while using functional near-infrared spectroscopy (fNIRS) to monitor changes in blood oxygen levels. Our findings revealed only a significant reduction in ΔOxy-Hb in the contralesional pre-motor cortex (z = −2.803, p = 0.005) during the FES-on walking sessions compared to the FES-off sessions. Furthermore, all regions in the FES-on session exhibited lower ΔOxy-Hb. Conversely, no significant differences were observed in ΔDeoxy-Hb. Moreover, a significant correlation was found between decrease in cPMC and the reduced cost time of walking under FES-on condition. The fNIRS analysis revealed diminished activation in the contralesional pre-motor cortex when walking with FES, implying that FES may facilitate a more automatic gait pattern while reducing a patient's reliance on contralesional cortical resources. The findings of this study lay the groundwork for long-term neural rehabilitation. [ABSTRACT FROM AUTHOR]

Introduction: Tumor tissues exhibit significantly lower oxygen partial pressure compared to normal tissues, leading to hypoxia in the tumor microenvironment and result in resistance to tumor treatments. Strategies to mitigate hypoxia include enhancing blood perfusion and oxygen supply, for example,by decomposing hydrogen peroxide within the tumor. Improving hypoxia in the tumor microenvironment could potentially improve the efficacy of cancer treatments. Previous studies have demonstrated that ultrasound of appropriate intensity when combined with microbubbles, can improve tumor blood perfusion. However, its effects on tumor hypoxia remain unclear. This study aimed to assess the effects of low-frequency non-focused ultrasound combined with microbubbles at different intensities on tumor microenvironment hypoxia and to identify the optimal ultrasound parameters for alleviating tumor hypoxia. Method: Rabbits with VX2 tumors received ultrasound and microbubble treatments at different acoustic pressures and pulse repetition frequencies. The changes in tumor tissue blood perfusion before and after treatment were observed by contrast enhanced ultrasound (CEUS). The changes in tumor tissue hypoxia before and after treatment were observed by measuring oxygen partial pressure directly with in tumor tissue and immunohistochemical staining for hypoxia-inducible factor-1α (HIF-1α). Results: Results indicated that low frequency, non-focused ultrasound at 0.5 MPa/20 Hz and 0.5 MPa/40 Hz, when combined with microbubbles, could increase tumor tissue blood perfusion and improve the hypoxia in tumor tissues. Discussion: This study provides a new method for improving hypoxia in the tumor microenvironment (TME) which could potentially improve the cancer treatments resistance. [ABSTRACT FROM AUTHOR]

Background: Pulse oximetry has not been thoroughly evaluated for assessment of oxygenation in conscious foals. Compared with invasive arterial blood sampling, it is a painless and non-invasive method for real-time monitoring of blood oxygen saturation. The aim of this prospective clinical study was to evaluate the usability, validity, and reliability of pulse oximetry at two measuring sites (lip and caudal abdominal skin fold) for blood oxygen saturation measurement in conscious foals with and without respiratory compromise. Thirty-two foals under one month of age were used. Nineteen foals had normal respiratory and cardiovascular function, and 13 had pneumonia. Pulse oximetry with a transmittance sensor was performed in triplicate on each foal's lip (n = 196 measurements) and/or skin fold (n = 338 measurements), and arterial blood sample was collected. The oxygen saturation values measured by pulse oximetry from the lip and skin fold were compared with each other (n = 58 measurement pairs) and with the calculated arterial oxygen saturation based on arterial blood samples (n = 93 measurement pairs). Furthermore, repeatability of the pulse oximetry measurements was assessed. Results: Measured blood oxygen saturation was clearly associated with the calculated saturation, but on average (± SD) it was 1.8 (± 3.3) percentage units higher from the lip and 5.7 (± 4.3) percentage units higher from the skin fold than the calculated saturation. In concurrent lip and skin fold measurements within a foal, the skin fold measurements were 2.4 (± 2.4) percentage units higher than the lip measurements. The repeatability of three pulse oximetry saturation measurement results was moderate to good and significantly improved when the measurement furthest from the middle-measured value was excluded. The most deviating measurement was often obtained first. Pulse oximetry in general was well tolerated and easy to perform, but as expected in conscious foals, movement and contact problems generated occasional technical difficulties in some individuals. Conclusions: In conscious foals, pulse oximetry with a transmittance sensor attached to the lip (but not to the skin fold) is a clinically applicable and valid method for arterial blood oxygen saturation determination. Several measurements should be obtained and outliers discarded to obtain a reliable result. [ABSTRACT FROM AUTHOR]

Background: Despite the fact that an increasing number of studies have focused on developing therapies for acute lung injury, managing acute respiratory distress syndrome (ARDS) remains a challenge in intensive care medicine. Whether the pathology of animal models with acute lung injury in prior studies differed from clinical symptoms of ARDS, resulting in questionable management for human ARDS. To evaluate precisely the therapeutic effect of transplanted stem cells or medications on acute lung injury, we developed an animal model of severe ARDS with lower lung function, capable of keeping the experimental animals survive with consistent reproducibility. Establishing this animal model could help develop the treatment of ARDS with higher efficiency. Results: In this approach, we intratracheally delivered bleomycin (BLM, 5 mg/rat) into rats' left trachea via a needle connected with polyethylene tube, and simultaneously rotated the rats to the left side by 60 degrees. Within seven days after the injury, we found that arterial blood oxygen saturation (SpO2) significantly decreased to 83.7%, partial pressure of arterial oxygen (PaO2) markedly reduced to 65.3 mmHg, partial pressure of arterial carbon dioxide (PaCO2) amplified to 49.2 mmHg, and the respiratory rate increased over time. Morphologically, the surface of the left lung appeared uneven on Day 1, the alveoli of the left lung disappeared on Day 2, and the left lung shrank on Day 7. A histological examination revealed that considerable cell infiltration began on Day 1 and lasted until Day 7, with a larger area of cell infiltration. Serum levels of IL-5, IL-6, IFN-γ, MCP-1, MIP-2, G-CSF, and TNF-α substantially rose on Day 7. Conclusions: This modified approach for BLM-induced lung injury provided a severe, stable, and one-sided (left-lobe) ARDS animal model with consistent reproducibility. The physiological symptoms observed in this severe ARDS animal model are entirely consistent with the characteristics of clinical ARDS. The establishment of this ARDS animal model could help develop treatment for ARDS. [ABSTRACT FROM AUTHOR]

Islet transplantation and more recently stem cell-derived islets were shown to successfully re-establish glycemic control in people with type 1 diabetes under immunosuppression. These results were achieved through intraportal infusion which leads to early graft losses and limits the capacity to contain and retrieve implanted cells in case of adverse events. Extra-hepatic sites and encapsulation devices have been developed to address these challenges and potentially create an immunoprotective or immune-privileged environment. Many strategies have achieved reversal of hyperglycemia in diabetic rodents. So far, the results have been less promising when transitioning to humans and larger animal models due to challenges in oxygenation and insulin delivery. We propose a versatile in vitro perfusion system to culture and experimentally study the function of centimeter-scale tissues and devices for insulin-secreting cell delivery. The system accommodates various tissue geometries, experimental readouts, and oxygenation tensions reflective of potential transplantation sites. We highlight the system's applications by using case studies to explore three prominent bioartificial endocrine pancreas (BAP) configurations: (I) with internal flow, (II) with internal flow and microvascularized, and (III) without internal flow. Oxygen concentration profiles modeled computationally were analogous to viability gradients observed experimentally through live/dead endpoint measurements and in case I, time-lapse fluorescence imaging was used to monitor the viability of GFP-expressing cells in real time. Intervascular BAPs were cultured under flow for up to 3 days and BAPs without internal flow for up to 7 days, showing glucose-responsive insulin secretion quantified through at-line non-disruptive sampling. This system can complement other preclinical platforms to de-risk and optimize BAPs and other artificial tissue designs prior to clinical studies. [ABSTRACT FROM AUTHOR]

The creation of innovative ultrasound contrast agents (UCAs) with the ability to monitor oxygen levels in real-time holds immense potential for advancing early diagnosis of various medical conditions such as hypoxic/reperfusion injury. In this study, we propose the development of oxygen sensitive UCAs using microbubbles composed of hemoglobin (HbMBs), which can function as sensors for blood oxygen levels. Previously, we performed a study highlighting the initial proof-of-concept efficacy of air-filled HbMBs in detecting oxygenation changes in vitro, offering a promising tool for clinically detecting tissue hypoxia. Nevertheless, a significant drawback of this approach is the potential for immune reactions and toxicity when hemoglobin is outside its natural red blood cell environment. Moreover, in vitro, HbMBs had low stability, with more than 90% decrease in their concentration after 120 minutes. Therefore, careful consideration of the surface properties and the gas core of HbMBs is crucial. Here, we formulated PEGylated HbMBs (PHbMBs), and investigated their stability, immunogenicity, and their acoustic response in oxygenated and deoxygenated media in vitro. We optimized PEGylated HbMBs (PHbMBs), showing a 42% reduction in immunogenicity and significantly improved stability in vitro, while maintaining their oxygen-binding and acoustic response. In vivo, PHbMBs demonstrated similar contrast enhancement to that of non-PEGylated MBs, demonstrating that PEGylation does not decrease HbMBs' acoustic signaling. Finally, changing the gas core from air to PFB increased PHbMBs' mean circulation time more than 11-fold, without diminishing their responsiveness to oxygen. Overall, the proposed oxygen sensitive PHbMBs offer a promising avenue for real-time acoustic detection of blood oxygen levels, paving the way for potential clinical applications in monitoring critically ill patients. This research explores the emergent field of Acoustic Oxygen Imaging in vivo using hemoglobin-based microbubbles. This innovative contrast agent approach involves imaging using crosslinked biomaterial comprised of the hemoglobin protein, aiming to transform the way we monitor blood oxygen levels with ultrasound. This work fundamentally addresses central concerns of improving bubble stability and circulation life for eventual clinical use, while minimizing toxicity. Importantly, we demonstrate that PEGylation of hemoglobin microbubbles enhances their stability, reduces immunogenicity, and maintains acoustic responsiveness. The incorporation of perfluorobutane into the bubble core increases the longevity of these microbubbles in circulation, while sustaining their oxygen sensitivity. Favorable in vivo results highlight the potential of this technology in real-time acoustic detection of blood oxygen levels. [Display omitted] [ABSTRACT FROM AUTHOR]

The use of submillimeter resolution functional magnetic resonance imaging (fMRI) is increasing in popularity due to the prospect of studying human brain activation non-invasively at the scale of cortical layers and columns. This method, known as laminar fMRI, is inherently signal-to-noise ratio (SNR)-limited, especially at lower field strengths, with the dominant noise source being of thermal origin. Furthermore, laminar fMRI is challenged with signal displacements due to draining vein effects in conventional gradient-echo blood oxygen level-dependent (BOLD) imaging contrasts. fMRI contrasts such as cerebral blood volume (CBV)-sensitive vascular space occupancy (VASO) sequences have the potential to mitigate draining vein effects. However, VASO comes along with another reduction in detection sensitivity. NOise Reduction with DIstribution Corrected (NORDIC) PCA (principal component analysis) is a denoising technique specifically aimed at suppressing thermal noise, which has proven useful for increasing the SNR of high-resolution functional data. While NORDIC has been examined for BOLD acquisitions, its application to VASO data has been limited, which was the focus of the present study. We present a preliminary analysis to evaluate NORDIC's capability to suppress thermal noise while preserving the VASO signal across a wide parameter space at 3T. For the data presented here, with a proper set of parameters, NORDIC reduced thermal noise with minimal bias on the underlying signal and preserved spatial resolution. Denoising performance was found to vary with different implementation strategies and parameter choices, for which we provide recommendations. We conclude that when applied properly, NORDIC has the potential to overcome the sensitivity limitations of laminar-specific VASO fMRI. Since very few groups currently have 3T VASO data, by sharing our analysis and code, we can compile and compare the effects of NORDIC across a broader range of acquisition parameters and study designs. Such a communal effort will help develop robust recommendations that will increase the utility of laminar fMRI at lower field strengths. [ABSTRACT FROM AUTHOR]

High-resolution awake mouse functional magnetic resonance imaging (fMRI) remains challenging despite extensive efforts to address motion-induced artifacts and stress. This study introduces an implantable radio frequency (RF) surface coil design that minimizes image distortion caused by the air/tissue interface of mouse brains while simultaneously serving as a headpost for fixation during scanning. Furthermore, this study provides a thorough acclimation method used to accustom animals to the MRI environment minimizing motion-induced artifacts. Using a 14 T scanner, high-resolution fMRI enabled brain-wide functional mapping of visual and vibrissa stimulation at 100 μm×100 μm×200 μm resolution with a 2 s per frame sampling rate. Besides activated ascending visual and vibrissa pathways, robust blood oxygen level-dependent (BOLD) responses were detected in the anterior cingulate cortex upon visual stimulation and spread through the ventral retrosplenial area (VRA) with vibrissa air-puff stimulation, demonstrating higher-order sensory processing in association cortices of awake mice. In particular, the rapid hemodynamic responses in VRA upon vibrissa stimulation showed a strong correlation with the hippocampus, thalamus, and prefrontal cortical areas. Cross-correlation analysis with designated VRA responses revealed early positive BOLD signals at the contralateral barrel cortex (BC) occurring 2 s prior to the air-puff in awake mice with repetitive stimulation, which was not detected using a randomized stimulation paradigm. This early BC activation indicated a learned anticipation through the vibrissa system and association cortices in awake mice under continuous exposure of repetitive air-puff stimulation. This work establishes a high-resolution awake mouse fMRI platform, enabling brain-wide functional mapping of sensory signal processing in higher association cortical areas. [ABSTRACT FROM AUTHOR]

With over 14 million people living above 3,500 m, the study of acclimatization and adaptation to high altitude in human populations is of increasing importance, where exposure to high altitude (HA) imposes a blood oxygenation and acid-base challenge. A sustained and augmented hypoxic ventilatory response protects oxygenation through ventilatory acclimatization, but elicits hypocapnia and respiratory alkalosis. A subsequent renally mediated compensatory metabolic acidosis corrects pH toward baseline values, with a high degree of interindividual variability. Differential renal compensation between acclimatizing lowlanders (LL) and Tibetan highlanders (TH; Sherpa) with ascent was previously unknown. We assessed ventilatory and renal acclimatization between unacclimatized LL and TH during incremental ascent from 1,400 m to 4,300 m in age-and sex-matched groups of 15-LL (8F) and 14-TH (7F) of confirmed Tibetan ancestry. We compared respiratory and renally mediated blood acid-base acclimatization (PCO2, [HCO3-], pH) in both groups before (1,400 m) and following day 8 to 9 of incremental ascent to 4,300 m. We found that following ascent to 4,300 m, LL had significantly lower PCO2 (P <0.0001) and [HCO3 -] (P <0.0001), and higher pH (P = 0.0037) than 1,400 m, suggesting respiratory alkalosis and only partial renal compensation. Conversely, TH had significantly lower PCO2 (P < 0.0001) and [HCO3 -] (P < 0.0001), but unchanged pH (P=0.1), suggesting full renal compensation, with significantly lower PCO2 (P = 0.01), [HCO3 -] (P < 0.0001) and pH (P=0.005) than LL at 4,300 m. This demonstration of differential integrative respiratory-renal responses between acclimatizing LL and TH may indicate selective pressure on TH, and highlights the important role of the kidneys in acclimatization. [ABSTRACT FROM AUTHOR]

Purpose: The selection and intensity of respiratory support for ARDS are guided by PaO2/FiO2. However, ventilator-induced lung injury (VILI) is linked to respiratory mechanics and ventilator settings. We explored whether the VILI risk is related to ARDS severity based on oxygenation. Methods: We analysed data on 228 ARDS subjects with PaO2/FiO2 < 200 mmHg, categorized into three severity groups: one based on PaO2/FiO2 ratio, and the others based on tertiles of predictors of VILI: mechanical power ratio (MPR) and driving pressure (DP). In each group of oxygenation-based ARDS severity and MPR and DP tertiles, we measured CT anatomy, gas exchange, respiratory mechanics, VILI prerequisites (lung elastance and lung gas volume), and VILI determinants (tidal volume, PEEP, airway pressures). Results: Predictors of VILI, such as MPR and DP, were similar across ARDS severity groups based on PaO2/FiO2 ratio, while oxygenation remained comparable across different levels of VILI risk defined by MPR and DP. Oxygenation impairment was associated with increased lung weight, recruitability, and reduced well-inflated tissue. In contrast, MPR and DP tertiles affected variables associated with the baby lung size, such as lung gas volume and well-inflated tissue. Mechanical ventilation intensity increased progressively across MPR and DP tertiles, but remained similar across PaO2/FiO2 severity groups. Conclusions: ARDS severity based on oxygenation impairment does not reflect the prerequisites and determinants of VILI. This should prompt a reconsideration of recommending respiratory support based on oxygenation impairment, rather than VILI determinants. [ABSTRACT FROM AUTHOR]

Blood pressure measurement is important in monitoring hypertension. However, blood pressure does not provide much information about renal condition in treated hypertension. This study aimed to evaluate renal oxygenation in hypertensive patients using T2* mapping. Subgroup analysis explored whether R2* values can guide adjustments in antihypertensive treatment. A total of 140 consecutive subjects were recruited: 87 hypertensive subjects and 53 normotensive subjects. Hypertensive subjects were classified into non-medication (non-med), angiotensin II receptor blocker (ARB), and non-ARB-treated groups. Each group was divided into good and poor control subgroups based on blood pressure at enrollment. T2* mapping was utilized to assess renal cortical and medullary R2* values. After a 2-year follow-up, subjects were categorized into stable and unstable based on the need for treatment modifications. The unstable subgroup had higher medullary R2* values than the stable subgroup in all followed patients (p < 0.05). Additionally, the unstable merged non-med with ARB subgroup had higher medullary R2* values overall (p < 0.05) and within the good control subgroup (p < 0.05). Patients with stable hypertension, especially those with good control managed through lifestyle modifications or ARBs, exhibited lower renal medullary R2* values, suggesting higher renal oxygenation. [ABSTRACT FROM AUTHOR]

Shrinkage, a heat-induced process, reorganizes collagen fibers, thereby reducing wound surface area. This technique, commonly applied in surgeries like periareolar mastopexy and skin grafting, is well-established. Despite its widespread use, modern imaging has recently enabled detailed observation of shrinkage's effects on tissue temperature and oxygenation. The aim of this study is to investigate the effects of shrinkage on histological level, temperature, and tissue oxygenation. Skin flaps were collected, marked, and subjected to shrinkage in vitro, with wound dimensions recorded before and after shrinkage. Biopsy samples were analyzed histologically. In our clinical set up, Snapshot NIR® and FLIR thermography were used to assess tissue oxygenation and temperature changes before and after shrinkage. Shrinkage significantly reduced wound area by almost 47% ± 8.5%, with a 16.5% ± 6.0% reduction in length and a 36.5% ± 7.7% reduction in width. Tissue temperature rose by an average of 38.3 °C post-shrinkage, reaching approximately 65 °C. A slight decrease in oxygen saturation was observed following shrinkage. Histological analyses reveal collagen fiber denaturation and structural reorganization. Thermal shrinkage is an effective method for reducing wound size and tension, demonstrating potential for facilitating larger full-thickness skin grafts. Although minor decreases in oxygenation were observed, shrinkage may enhance wound healing by reducing tension at wound edges. Further studies are needed to quantify its impact on functional and cosmetic outcomes. [ABSTRACT FROM AUTHOR]

Neonatal hypoxic-ischemic encephalopathy (HIE) is a critical condition resulting from impaired oxygen and blood flow to the brain during birth, leading to neuroinflammation, neuronal apoptosis, and long-term neurological deficits. Despite the use of therapeutic hypothermia, current treatments remain inadequate in fully preventing brain damage. Recent advances in mesenchymal stem cell-derived extracellular vesicles (MSC-EVs) offer a novel, cell-free therapeutic approach, as these EVs can cross the blood-brain barrier (BBB) and deliver functional microRNAs (miRNAs) to modulate key pathways involved in inflammation and neuroprotection. This review examines how specific miRNAs encapsulated in MSC-EVs—including miR-21, miR-124, miR-146, and the miR-17-92 cluster—target the complex inflammatory responses that drive HIE pathology. By modulating pathways such as NF-κB, STAT3, and PI3K/Akt, these miRNAs influence neuroinflammatory processes, reduce neuronal apoptosis, and promote tissue repair. The aim is to assess the therapeutic potential of miRNA-loaded MSC-EVs in mitigating inflammation and neuronal damage, thus addressing the limitations of current therapies like therapeutic hypothermia. [ABSTRACT FROM AUTHOR]

Introduction: As wearable technology becomes increasingly popular and sophisticated, independent validation is needed to determine its accuracy and potential applications. Therefore, the purpose of this study was to evaluate the accuracy (validity) of VO2max estimates and blood oxygen saturation measured via pulse oximetry using the Garmin fēnix 6 with a general population participant pool. Methods: We recruited apparently healthy individuals (both active and sedentary) for VO2max (n = 19) and pulse oximetry testing (n = 22). VO2max was assessed through a graded exercise test and an outdoor run, comparing results from the Garmin fēnix 6 to a criterion measurement obtained from a metabolic system. Pulse oximetry involved comparing fēnix 6 readings under normoxic and hypoxic conditions against a medical-grade pulse oximeter. Data analysis included descriptive statistics, error analysis, correlation analysis, equivalence testing, and bias assessment, with the validation criteria set at a concordance correlation coefficient (CCC) > 0.7 and a mean absolute percentage error (MAPE) < 10%. Results: The Garmin fēnix 6 provided accurate VO2max estimates, closely aligning with the 15 s and 30 s averaged laboratory data (MAPE for 30 s avg = 7.05%; Lin's concordance correlation coefficient for 30 s avg = 0.73). However, it failed to accurately measure blood oxygen saturation (BOS) under any condition or combined analysis (MAPE for combined conditions BOS = 4.29%; Lin's concordance correlation coefficient for combined conditions BOS = 0.10). Conclusion: While the Garmin fēnix 6 shows promise for estimating the VO2max, reflecting its utility for both individuals and researchers, it falls short in accurately measuring BOS, limiting its application for monitoring acclimatization and managing pulmonary diseases. This research underscores the importance of validating wearable technology to leverage its full potential in enhancing personal health and advancing public health research. [ABSTRACT FROM AUTHOR]

The delayed eukaryote evolution during the mid-Proterozoic may have been linked to prolonged low oxygen levels during this period. Two short oxygenation events have recently been identified at ca. 1.57 Ga and ca. 1.4 Ga, but the redox conditions during the intervening interval remain poorly constrained. In this study, we conducted mineralogical and geochemical investigations on three sections of the Wumishan Formation (ca. 1.52-1.47 Ga) that were deposited between the two oxygenation events in the Yanliao basin. The results revealed two distinct changes in carbonate mineralogy and precipitation style associated with concurrent changes in carbonate I/(Ca + Mg): a transition from intervals with positive I/(Ca + Mg) anomalies and abundant watercolumn carbonate mud to intervals with no I/(Ca + Mg) anomalies and abundant seafloor precipitates, suggesting a shift from suboxic to anoxic conditions in shallow seawater. In both of the suboxic intervals, I/(Ca + Mg) values reached 0.5-2.6 µmol/mol, with negative Ce anomalies (Ce/Ce*(SN) = 0.69; data from literature) occurring in the later interval (ca. 1.48 Ga). The results suggest significant redox fluctuations in the shallow seawater during the Mesoproterozoic. However, these pulsed oxygenation episodes may not have been sufficient to sustain the continuous evolution of early eukaryotes. [ABSTRACT FROM AUTHOR]

Purpose: Ischemic pre-conditioning (IPC) offers protection against future ischemic events and may improve sports performance due to several mechanisms at local and systemic levels. This study investigates the local effects on muscle contractility in electrically induced muscle contractions, thus effectively excluding any uncontrolled change in the motor drive. Methods: Twenty-one subjects were divided into two groups: 12 subjects in the IPC group (3 × 5/5 min right arm ischemia/reperfusion; cuff pressure 250 mmHg) and 9 subjects in the SHAM group (same treatment at 20 mmHg). The adductor pollicis was contracted by supramaximal stimulation of the ulnar nerve with single pulses, trains of stimuli (5, 8, 10 and 12 Hz, 1-s duration) and bursts (4 pulses, 25 Hz), all separated by 5-s intervals. The stimulation sequence was delivered before and 15 and 30 min after IPC/SHAM treatment. The isometric contraction force, the superficial electromyographic signal, and tissue oxygenation were continuously monitored. Results: A significant force decrease in time was observed at 8, 10 (p < 0.01) and 12 Hz (p < 0.05) along with a decrease in half-relaxation time in single twitches and bursts (p = 0.01), regardless of treatment. This general time-related weakening was more marked in IPC than SHAM at 5-Hz stimulation. No effects were observed on the magnitude of the superficial electromyographic signal. Conclusion: Data indicate that IPC does not increase muscle force during electrically stimulated contractions, supporting the idea that IPC's ergogenic effects are not due to increased muscle contractility. [ABSTRACT FROM AUTHOR]

The decline in sleep quality induced by hypoxia is the main environmental exposure risk affecting the physiological health of high-altitude residents. The long-term effects of oxygen therapy on the sleep quality and health of highlanders remain unclear. This study aims to evaluate the impact of chronic oxygen therapy on sleep and health, providing a scientific basis for the establishment of regional centralized oxygen supply and the implementation of health regulations to improve sleep quality and health in plateau areas. Conducted over a span of three years at an altitude of 3255 m in the Tibetan Plateau, this study included 317 participants and meticulously recorded sleep data for 1398 nights. The generalized estimation equation was used to analyze the impact of oxygen supply on sleep quality, physiological parameters, and indoor environment. The research found that long-term oxygen therapy significantly reduced the pulse rate of highland residents, increased their blood oxygen saturation, and consequently decreased their risk of cardiovascular disease. Oxygen-enriched environments improved the sleep quality of highland dwellers, significantly increasing their sleep efficiency, duration of rapid eye movement sleep and deep sleep, and subjective sleep quality evaluation, while also significantly reducing central sleep apnea-induced nighttime awakening events. Long-term chronic oxygen therapy is beneficial to highland residents in terms of sleep respiratory rhythm, sleep quality, and cardiovascular function. It is imperative for both the local inhabitants of high-altitude areas and the local health authorities to be aware of the risks of hypoxia and the health benefits of oxygen therapy. [Display omitted] • Central respiratory-induced arousal is the primary sleep issue in highlanders. • Oxygen-enriched environment improves sleep quality in highlanders. • Long-term oxygen therapy reduces cardiovascular disease risk in highlanders. [ABSTRACT FROM AUTHOR]

Introduction Hypoxia presents a physiological challenge to the Warfighters during military aviation and subterranean warfare operations by decreasing the supply of oxygen to the brain, which results in a reduced cognitive function depending on the magnitude and duration of hypoxic exposure. Moderate hypoxic exposures, fractions of inspired oxygen (FiO2) of 0.11 to 0.14, show no effects on simple tasks, but complex tasks like working memory may be hindered. Unfortunately, people often cannot recognize their own symptoms of hypoxemia, which are individualistic at moderate hypoxic exposure. Thus, screening tools, like gamified cognitive assessments, during moderate hypoxia may provide personnel objective feedback to initiate safety protocols before a possible accident. However, whether gamified assessments of working memory are sensitive to moderate hypoxia is unknown. Therefore, we tested the hypothesis which moderate normobaric hypoxia decreases gamified working memory performance when accounting for the individualistic responses of arterial blood oxygen saturations. Materials and methods Following 3 consecutive days of 2 practice sessions per day, 30 healthy adults (25 ± 5 years, 10 women) completed three 1-min rounds of the tablet-based working memory game (Backtracker, Statespace Labs, Inc.) at baseline and 60 and 90 min after exposure to FiO2 (= 0.138 ± 0.002 [hypoxia] and 0.201± 0.004 [normoxia] oxygen). Both conditions were completed on the same day and administered in a single-blind, block randomized manner. Arterial oxyhemoglobin saturation was estimated via forehead pulse oximetry (SpO2). Data were analyzed using linear mixed effects modeling. Results Compared to normoxia (99 ± 1%), SpO2 was lower (P  < .001) at 60 (90 ± 2%) and 90 (90 ± 2%) min of hypoxia. A decrease in SpO2 was associated with a statistically significant decrease in the proportion of both tiles with the correct location (P  < .02; −0.016) and correct order of appearance recalled (P  < .01; −0.016). A decrease in SpO2 was associated with a statistically significant decrease in median time to first tap (P  < .01; −0.041 s) and median time between taps (P  < .01; −0.030 s). A significant interaction effect between the SpO2 decrease and baseline performance was found for proportion of tiles with the correct location recalled (P  < .05; −0.014), median time to first tap (P < .01; −0.070 s), and median time between taps (P  < .01; −0.037 s). A significant interaction effect between the SpO2 decrease and the path length was found for the proportion of tiles with the correct location recalled (P  < .01; +0.021), median time to first tap (P  < .01; −0.036 s), and median time between taps (P  < .01; −0.043 s). Conclusions These findings indicate that greater decreases in SpO2 during moderate hypoxic exposure hinder performance on a gamified assessment of working memory as measured by the proportion of correctly identified order and location of tiles. Considering the statistically significant decrease in both median time to first tap and median time between taps associated with the decrease in SpO2, participants are taking less time to plan or execute movements, which may compound or independently contribute to spatial and temporal memory mistakes. [ABSTRACT FROM AUTHOR]

Developmental dyslexia (DD) is one of the most common learning disorders, affecting millions of children and adults worldwide. To date, scientific research has attempted to explain DD primarily based on pathophysiological alterations in the cerebral cortex. In contrast, several decades ago, pioneering research on five post-mortem human brains suggested that a core characteristic of DD might be morphological alterations in a specific subdivision of the visual thalamus—the magnocellular lateral geniculate nucleus (M-LGN). However, due to considerable technical challenges in investigating LGN subdivisions non-invasively in humans, this finding was never confirmed in vivo , and its relevance for DD pathology remained highly controversial. Here, we leveraged recent advances in high resolution MRI at high field strength (7 T) to investigate the M-LGN in DD in vivo. Using a case-control design, we acquired data from a large sample of young adults with DD (n = 26; age 28 ± 7 years; 13 females) and matched control participants (n = 28; age 27 ± 6 years; 15 females). Each participant completed a comprehensive diagnostic behavioural test battery and participated in two MRI sessions, including three functional MRI experiments and one structural MRI acquisition. We measured blood oxygen level-dependent responses and longitudinal relaxation rates to compare both groups on LGN subdivision function and myelination. Based on previous research, we hypothesized that the M-LGN is altered in DD and that these alterations are associated with a key DD diagnostic score, i.e. rapid letter and number naming. The results showed aberrant responses of the M-LGN in DD compared to controls, which was reflected in a different functional lateralization of this subdivision between groups. These alterations were associated with rapid letter and number naming performance, specifically in male DD. We also found lateralization differences in the longitudinal relaxation rates of the M-LGN in DD relative to controls. Conversely, the other main subdivision of the LGN, the parvocellular LGN (P-LGN), showed comparable blood oxygen level-dependent responses and longitudinal relaxation rates between groups. The present study is the first to unequivocally show that M-LGN alterations are a hallmark of DD, affecting both the function and microstructure of this subdivision. It further provides a first functional interpretation of M-LGN alterations and a basis for a better understanding of sex-specific differences in DD with implications for prospective diagnostic and treatment strategies. [ABSTRACT FROM AUTHOR]

Rather than a passive reflection of nociception, pain is shaped by the interplay between one's experiences, current cognitive-affective states, and expectations. The placebo response, a paradoxical yet reliable phenomenon, is postulated to reduce pain by engaging mechanisms shared with active therapies. It has been assumed that mindfulness meditation, practiced by sustaining nonjudgmental awareness of arising sensory events, merely reflects mechanisms evoked by placebo. Recently, brain-based multivariate pattern analysis has been validated to successfully disentangle nociceptive-specific, negative affective, and placebo-based dimensions of the subjective pain experience. To determine whether mindfulness meditation engages distinct brain mechanisms from placebo and sham mindfulness to reduce pain, multivariate pattern analysis pain signatures were applied across 2 randomized clinical trials that employed overlapping psychophysical pain testing procedures (49 °C noxious heat; visual analog pain scales) and distinct functional magnetic resonance imaging techniques (blood oxygen level–dependent; perfusion based). After baseline pain testing, 115 healthy participants were randomized into a 4-session mindfulness meditation (n = 37), placebo-cream conditioning (n = 19), sham mindfulness meditation (n = 20), or book-listening control (n = 39) intervention. After each intervention, noxious heat was administered during functional magnetic resonance imaging and each manipulation. A double dissociation in the multivariate pattern analysis signatures supporting pain regulation was revealed by mindfulness meditation compared with placebo cream. Mindfulness meditation produced significantly greater reductions in pain intensity and pain unpleasantness ratings and nociceptive-specific and negative affective pain signatures than placebo cream, sham mindfulness meditation, and control interventions. The placebo-cream group significantly lowered the placebo-based signature. Mindfulness meditation and placebo engaged distinct and granular neural pain signatures to reduce pain. [ABSTRACT FROM AUTHOR]

Power Doppler ultrasonography is used to measure blood flow within a given muscle, otherwise known as intramuscular blood flow. However, it is not fully understood how intramuscular blood flow and muscle oxygenation change with repetitive muscle contraction. The present study was conducted to assess changes in intramuscular blood flow and muscle oxygenation of the vastus lateralis (VL) during intermittent and incremental contractions. Fifteen healthy male subjects (21.7 ± 2.6 years) performed intermittent (5 s contraction, 5 s relaxation) and incremental isometric knee extensions at 30%, 40%, 50%, 60% and 70% of maximal voluntary contraction (MVC) until task failure. Intramuscular blood flow and muscle oxygen saturation (StO2${{S}_{{\mathrm{t}}{{{\mathrm{O}}}_2}}}$) were simultaneously measured using power Doppler ultrasonography and near‐infrared spectroscopy, respectively, from the right VL of the mid‐thigh. Intramuscular blood flow was increased from 0.5 ± 0.5% at rest to 13.9 ± 9.5% at task failure. Intramuscular blood flow significantly increased from rest to 30% and 40% MVC (P = 0.001), and StO2${{S}_{{\mathrm{t}}{{{\mathrm{O}}}_2}}}$ significantly decreased from 30% to 70% MVC (P = 0.004). These results indicate that intramuscular blood flow and StO2${{S}_{{\mathrm{t}}{{{\mathrm{O}}}_2}}}$ show different patterns of change, suggesting that the contribution of intramuscular blood flow to oxygen supply decreases within the VL at moderate and higher exercise intensities. What is the central question of this study?How do intramuscular blood flow and muscle oxygenation change with intermittent and incremental muscle contractions?What is the main finding and its importance?Intramuscular blood flow reached a plateau above moderate exercise intensities, but muscle oxygen saturation continued to decrease. These results indicate that the contribution of intramuscular blood flow to oxygen supply varies with exercise intensity. [ABSTRACT FROM AUTHOR]

People with peripheral arterial disease (PAD) and intermittent claudication (IC) experience impaired walking due to an imbalance between muscle oxygen supply and demand during exercise. Studies with near-infrared spectroscopy (NIRS) during treadmill tests reveal notable tissue deoxygenation with slow recovery. This cross-sectional study aimed to compare behavior of calf muscle oxygenation during the incremental shuttle walking test (ISWT) with a continuous treadmill test (3.2 km/h, 10% incline) and to correlate NIRS results between tests in PAD patients. Sixty individuals with IC, 37 men (61.7%), mean age 66.25 ± 10.35 years participated in the study. Both tests were performed on the same day with a 30-minute rest, in randomized order. NIRS-derived calf muscle tissue oxygenation variables were measured at rest and during exercise. Typical PAD tissue oxygenation patterns were observed in both tests, with significant differences (p < 0.05) in oxygenation values during exercise for the variables delta of tissue oxygen saturation (ΔStO2) and reoxygenation rates. All tissue oxygenation variables analyzed, except reoxygenation rate, showed a significant and directly proportional correlation between the two tests. These results suggest that NIRS during ISWT could be a viable method for assessing tissue oxygenation in PAD. [ABSTRACT FROM AUTHOR]

In this article, we explored 18 studies showing the impact of the intraoperative recruitment maneuver on patients with obesity undergoing laparoscopic surgery. A recruiting maneuver accompanied by a more significant positive end-expiratory pressure enhances intraoperative oxygenation and respiratory mechanics in obese patients undergoing surgery. They are safe and do not have unfavorable hemodynamic consequences. [ABSTRACT FROM AUTHOR]

Acute, intermittent exposure to mild hypoxia increases sympathetic nervous system activity, decreases arterial shear rate, and increases blood pressure (BP) in young men. Given that the BP-raising effects of intermittent hypoxia (IH) are less evident in young women, we sought to examine the influence of sex on macro- and microvascular function following IH. BP, macrovascular function [brachial artery flow-mediated dilation (FMD)], microvascular function [reactive hyperemia area under the curve (RHAUC)], and brachial artery shear rate [shear rate area under the curve (SRAUC)] were measured before and following 30 min of IH in 18 young adults (8 women, 23 ± 5 yr). IH elicited an average nadir blood oxygen saturation (S p O 2 ) of 92 ± 3% (P < 0.0001 vs. baseline). In men, brachial systolic (bSBP; 116 ± 6 to 122 ± 7 mmHg, P = 0.001) and diastolic (bDBP; 116 ± 6 to 122 ± 7 mmHg, P = 0.001) BPs increased from baseline following IH. bSBP (110 ± 8 to 111 ± 7 mmHg, P = 0.67) and bDBP (64 ± 7 to 68 ± 7 mmHg, P = 0.12) were unchanged in women after IH. Men maintained macrovascular function after IH (ΔFMD: 0.75 ± 2.44%), whereas women exhibited a decline (ΔFMD: −3.09 ± 2.64%, P = 0.006 vs. men). Microvascular function and shear rate declined following IH independent of sex (RHAUC: 597 ± 306 to 467 ± 205 mL/min, P = 0.049; SRAUC: 1772 ± 907 to 1439 ± 596 s−1, P = 0.040). Acute mild IH increases BP in healthy men but not women. In women, both micro- and macrovascular functions are lower following acute mild IH; in contrast, only microvascular function is lower in men. The sex-specific effects of IH on BP and macrovascular function may have important implications for the potential beneficial effects of IH. NEW & NOTEWORTHY: The present study aimed to investigate the influence of sex on vascular responses to 30 min of acute, mild intermittent hypoxia. Men and women exhibited similar decreases in arterial shear rate and microvascular function after intermittent hypoxia. Although men exhibited increases in blood pressure but no changes in macrovascular function, women exhibited significant decreases in macrovascular function despite no changes in blood pressure. Sex may influence the potential hormetic effects of intermittent hypoxia. [ABSTRACT FROM AUTHOR]

Myopia, a major public health problem, involves axial elongation and thinning of all layers of the eye, including sclera, choroid and retina, which defocuses incoming light and thereby blurs vision. How the various populations of glia in the retina are involved in the disorder is unclear. Astrocytes and Müller cells provide structural support to the retina. Astrogliosis in myopia may influence blood oxygen supply, neuronal function, and axon diameter, which in turn may affect signal conduction. Müller cells act as a sensor of mechanical stretching in myopia and trigger downstream molecular responses. Microglia, for their part, may exhibit a reactive morphology and elevated response to inflammation in myopia. This review assesses current knowledge about how myopia may involve retinal glia, and it explores directions for future research into that question. Summary diagram of the potential mechanism of retinal glial cells implicated in myopia. The figure shows the anatomical relationship of the three retinal glial cells including astrocyte, microglia, and Müller cells to other neurons, and summarizes the potential mechanisms by which glial cells respond to myopia. [ABSTRACT FROM AUTHOR]

Red blood cells (RBCs) are a vital component of the body's oxygen supply system. In addition to being pro-oxidants, they are also essential components of the body's antioxidant defense mechanism. RBCs are susceptible to both endogenous and exogenous sources of oxidants. Oxyhemoglobin autoxidation is the primary source of endogenous RBC oxidant production, which produces superoxide radicals and hydrogen peroxide. Potent exogenous oxidants from other blood cells and the surrounding endothelium can also enter RBCs. Both enzymatic (like glutathione peroxidase) and non-enzymatic (like glutathione) mechanisms can neutralize oxidants. These systems are generally referred to as oxidant scavengers or antioxidants, and they work to neutralize these harmful molecules (i.e., oxidants). While their antioxidative capabilities are essential to their physiological functions and delivering oxygen to tissues, their pro-oxidant behavior plays a part in several human pathologies. The redox-related changes in RBCs can have an impact on their function and fate. The balance between pro-oxidants and antioxidants determines the oxidative status of cells, which affects signal transduction, differentiation, and proliferation. When pro-oxidant activity exceeds antioxidative capacity, oxidative stress occurs, leading to cytotoxicity. This type of stress has been linked to various pathologies, including hemolytic anemia. This review compiles the most recent literature investigating the connections between RBC redox biochemistry, antioxidants, and diverse disorders. [ABSTRACT FROM AUTHOR]

Background/Aim: Tumors exhibit impaired blood flow and hypoxic areas, which can reduce the effectiveness of treatments. Characterizing these tumor features can inform treatment decisions, including the use of vasculature modulation therapies. Imaging provides insight into these characteristics, with techniques varying between clinical and preclinical settings. Materials and Methods: To investigate changes in different tumor regions over time, R2* values from blood oxygen-level dependent MRI (BOLD-MRI), blood flow from power Doppler ultrasound, and oxygen saturation from photoacoustic ultrasound were analyzed and compared to CD31+ and pimonidazole tissue staining. To aid in preclinical translation, the fluorescence of a hypoxia probe was also compared to ultrasound techniques. Results: The imaging techniques detected tumor heterogeneity and an overall decrease in blood flow and oxygen levels over time. The analysis found varying correlations between regions, indicating an indirect relationship between imaging outcomes, which is influenced by external factors. Regional analysis allowed for more accurate results, as areas less affected by various factors were examined separately from highly impacted regions, aiding in their identification. Conclusion: Examining tumor regions with multiple imaging techniques allowed for better understanding and identification of modality-specific limitations, as certain techniques may incorrectly suggest that tumors are more vascularized and less hypoxic than they are. [ABSTRACT FROM AUTHOR]

Cerebral glucose and oxygen metabolism and blood perfusion play key roles in neuroenergetics and oxidative phosphorylation to produce adenosine triphosphate (ATP) energy molecules in supporting cellular activity and brain function. Their impairments have been linked to numerous brain disorders. This study aimed to develop an in vivo magnetic resonance spectroscopy (MRS) method capable of simultaneously assessing and quantifying the major cerebral metabolic rates of glucose (CMRGlc) and oxygen (CMRO2) consumption, lactate formation (CMRLac), and tricarboxylic acid (TCA) cycle (VTCA); cerebral blood flow (CBF); and oxygen extraction fraction (OEF) via a single dynamic MRS measurement using an interleaved deuterium (2H) and oxygen‐17 (17O) MRS approach. We introduced a single‐loop multifrequency radio‐frequency (RF) surface coil that can be used to acquire proton (1H) magnetic resonance imaging (MRI) or interleaved low‐γ X‐nuclei 2H and 17O MRS. By combining this RF coil with a modified MRS pulse sequence, 17O‐isotope‐labeled oxygen gas inhalation, and intravenous 2H‐isotope‐labeled glucose administration, we demonstrate for the first time the feasibility of simultaneously and quantitatively measuring six important physiological parameters, CMRGlc, CMRO2, CMRLac, VTCA, CBF, and OEF, in rat brains at 16.4 T. The interleaved 2H–17O MRS technique should be readily adapted to image and study cerebral energy metabolism and perfusion in healthy and diseased brains. [ABSTRACT FROM AUTHOR]

Spin‐lock (SL) pulses have been proposed to directly detect neuronal activity otherwise inaccessible through standard functional magnetic resonance imaging. However, the practical limits of this technique remain unexplored. Key challenges in SL‐based detection include ultra‐weak signal variations, sensitivity to magnetic field inhomogeneities, and potential contamination from blood oxygen level‐dependent effects, all of which hinder the reliable isolation of neuronal signals. This pilot study evaluates the performance of the stimulus‐induced rotary saturation (SIRS) technique to map visual stimulation response in the human cortex. A rotary echo spin‐lock (RESL) preparation followed by a 2D echo planar imaging readout was used to investigate 12 healthy subjects at rest and during continuous exposure to 8 Hz flickering light. The SL amplitude was fixed to the target neuroelectric oscillations at that frequency. The signal variance was used as contrast metric, and two alternative post‐processing pipelines (regression‐filtering‐rectification and normalized subtraction) were statistically evaluated. Higher variance in the SL signal was detected in four of the 12 subjects. Although group‐level analysis indicated activation in the occipital pole, analysis of variance revealed that this difference was not statistically significant, highlighting the need for comparable control measures and more robust preparations. Further optimization in sensitivity and robustness is required to noninvasively detect physiological neuroelectric activity in the human brain. [ABSTRACT FROM AUTHOR]

Proper oxygen delivery through the microvasculature to injury site is essential to ensure the metabolic cascade during wound healing. Adaptation of vascular structure and oxygenation is key to unravel the regulation of blood perfusion, oxygen distribution and new tissue formation. Yet, visualizing micrometabolic responses at large scale in unperturbed living tissue remains challenging. We studied full-thickness excisional wounds in the mouse dorsal skin in vivo using ultrasound-aided spectroscopic large-scale optoacoustic microscopy. Skin layer-specific vascularization is visualized at capillary resolution over centimeter-scale field-of-view in a non-invasive, label-free manner. Different vascular parameters, including oxygenation, diameter and its irregularity, tortuosity and angular alignment, show distinct spatial and temporal variations. Elevated oxygenation is manifested close to the wound at day 4 with the trend accompanied by reduction in diameter over time. Angular alignment increases over time, indicating a more directed blood supply towards the wound. Our observations indicate that wound angiogenesis initiates as capillary sprouting with enlarged newborn vessels and elevated oxygenation around the wound, with the vessels normalizing in size and oxygenation during remodeling. Our study provides insight into micrometabolic profiles surrounding the healing wound, setting the stage for preclinical studies on oxygen delivery mechanisms in pathological skin conditions and during pharmacological interventions. Ultrasound-aided spectroscopic large-scale optoacoustic microscopy reveals layer-specific spatiotemporal dynamics of microvascular oxygenation during dorsal skin wound healing in mice. [ABSTRACT FROM AUTHOR]

Background: Attention deficit hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder characterized by inattention, impulsivity, and hyperactivity. With the continuous development of neuromodulation technology, Repetitive Transcranial Magnetic Stimulation (rTMS) has emerged as a potential non-invasive treatment for ADHD. However, there is a lack of research on the mechanism of rTMS for ADHD. Functional near infrared spectroscopy (fNIRS) is an optical imaging technique that reflects the brain function by measuring changes in blood oxygen concentration in brain tissue. Consequently, this research utilized fNIRS to examine the impact of rTMS on the core symptoms and prefrontal cortex activation in children with ADHD, which provides a reference for the clinical application of rTMS in the treatment of ADHD. Methods: Forty children with ADHD were chosen as research subjects and randomly assigned to two groups: a treatment group (20 subjects) and a control group (20 subjects). The control group received non-pharmacological interventions, whereas the treatment group was administered rTMS in conjunction with non-pharmacological interventions. Clinical symptom improvement was evaluated using SNAP-IV scale scores both before and after treatment. Additionally, fNIRS was utilized to monitor alterations in the relative concentrations of oxyhemoglobin (HbO2) and deoxyhemoglobin (HbR) in the prefrontal cortex during resting state and during the Go/no-go task state, both pre- and post-treatment. Results: In conclusion, the study comprised 17 participants in the treatment group and 18 in the control group. Initially, the SNAP-scale scores were comparable between the groups, with no significant differences observed (p > 0.05). Post-treatment, a notable reduction in SNAP-scale scores was evident (p < 0.05), with the treatment group exhibiting a more pronounced decrease (p < 0.05). Following the intervention, both groups demonstrated enhanced Resting-state functional connectivity (RSFC) in the prefrontal cortex, as indicated by a significant increase compared to pre-treatment levels (p < 0.05). Specifically, the treatment group showed superior RSFC in the left dorsolateral prefrontal cortex, right dorsolateral prefrontal cortex, left medial prefrontal cortex, and right medial prefrontal cortex compared to the control group (p < 0.05). However, no significant differences were noted in RSFC of the left and right temporal lobes between the two groups (p > 0.05). In the Go/no-go task, the treatment group recorded higher mean HbO2 concentrations in the aforementioned prefrontal cortical regions compared to the control group (p < 0.05). Conversely, no statistically significant disparities were observed in the left and right temporal lobes of both groups. Conclusion: rTMS shows promise as a treatment for ADHD by modulating prefrontal cortical activation. fNIRS provides a valuable method for assessing these effects, offering insights into the neurobiological mechanisms underlying rTMS therapy. [ABSTRACT FROM AUTHOR]

Background: Guidelines advocate pulmonary function testing (PFT) in preoperative evaluation before lung resection. Although forced expiratory volume in 1 s (FEV1) and diffusing capacity of the lungs for carbon monoxide (DLCO) are recommended, they are often poor predictors of complications. Objectives: Determine if PFT testing results other than FEV1 and DLCO are associated with post-operative complications. We hypothesized that other PFT test results may improve the prediction of post-operative complications. Design: Retrospective cohort study of a single institution. Methods: We analyzed patients who underwent anatomic lung resections from 1/2007 to 1/2017. Percent predicted post-operative (ppo) PFT values were calculated for each test result. Outcome of interest was any post-operative complication. Wilcoxon rank-sum and multivariable regression were used to determine the relationship of PFT results to post-operative complications. Results: We analyzed 922 patients who underwent anatomic lung resections. Complications occurred in 240 (26.0%) patients, and mortality occurred in 12 (1.3%) patients. In univariate analysis, predicted and percent predicted post-operative (ppo) forced vital capacity (FVC), FEV1, FEF2575, DLCO, DLCO/VA, and VC values were predictors of post-operative complications. Multivariable logistic regression found no independent relationship of test results to post-operative complications, likely reflecting the collinearity of PFT results. Conclusion: Our findings suggest that non-traditional PFTs, such as FVC, may enhance risk stratification for post-operative complications following anatomic lung resection. Notably, traditional parameters like FEV1 and DLCO were not independently predictive, highlighting the need to reconsider their role in isolation. These findings highlight the need to reconsider how PFT are used in surgical risk stratification given high levels of collinearity. Plain language summary: Using less common lung tests to predict complications after lung surgery When doctors plan lung surgery, they use tests to check how well the lungs work. Two common tests are FEV1, which measures how much air you can blow out in one second, and DLCO, which checks how well your lungs move oxygen into your blood. But sometimes these tests don't do a good job of predicting if a patient will have problems after surgery. In our study, we looked at other lung tests to see if they could help doctors better predict who might have trouble after surgery. We studied 922 patients who had lung surgery at our hospital over 10 years. We used the usual tests (FEV1 and DLCO), and we also looked at other tests like forced vital capacity (FVC), which measures how much air a person can blow out after taking a deep breath. We found that these extra tests can help give a better picture of a patient's lung health and risk of complications. For example, FVC was helpful in predicting problems after surgery. But when we looked at all the test results together, their usefulness decreased because some of the tests measure similar things. Our study shows that while the usual lung tests are helpful, adding other lung tests could make it easier to predict problems before surgery. This might help doctors decide which patients are good candidates for surgery and which patients need different types of care. [ABSTRACT FROM AUTHOR]

The recent advances in flexible and wearable electronics, along with ubiquitous biosensing technologies have enabled the continuous monitoring of health conditions outside of medical facilities. Health‐monitoring tools based on wearable sensors must be more user‐friendly, informative, and cost‐effective for daily applications owing to the increased prevalence of chronic diseases and mental illnesses. In this study, a flexible and multifunctional skin patch and a custom‐designed application for wirelessly monitoring the wearer's physical and mental health conditions are proposed. The optimized design and soft‐covering materials of the skin patch enable long‐term attachment to the body without causing discomfort or irritation to the wearer. Onboard processing of the signals enables real‐time monitoring and signal acquisition of multiple biomarkers, including the blood oxygen saturation level (SpO2), pulse rate (PR), pulse rate variability (PRV), perfusion index (PI), body movement, and temperature during daily activities. The photoplethysmography (PPG)‐based biomarkers acquired from various body sites are compared and calibrated to verify its performance. Demonstrated pilot trial shows the potential application of the skin patch for clinical decision support in psychiatric assessments that can be implemented as an assistive mental illness monitoring system for psychiatrists and researchers. [ABSTRACT FROM AUTHOR]

Background Methods Results Conclusions Preclinical and clinical studies have demonstrated the advantages of oxygenated hypothermic machine perfusion (HMPO2) during kidney preservation. However, the optimal oxygenation levels during HMPO2 remain undetermined. The aim of this study was to compare different levels of oxygenation (0%, 21%, 50%, and 100%) during 22 h of active oxygenated HMP (HMPO2) using oxygen preloading by bubbling oxygenation in the preservation solution and continuous surface oxygenation during MP in a porcine DCD model.After 60 min of warm ischemia time, both kidneys of an 80 kg pig were procured and randomized to one of the following groups: (1) 22‐h static cold storage (n = 6), (2) 22‐h HMP without active oxygenation (n = 6), (3) 22‐h HMPO2 21% O2 (n = 6), (4) 22‐h HMPO2 50% O2 (n = 6), and (5) 22‐h HMPO2 100% O2 (n = 6). The primary outcome measure was to compare the different oxygen levels among the different groups assessed by cortex kidney tissue oxygen partial pressures (tpO2).Continuous HMPO2 resulted in a significant modification of cortex kidney tpO2. In addition, tpO2 was dependent on the percentage of oxygenation. One hundred percent oxygen resulted in a significantly higher tpO2 compared to all other study groups. In line with that, ATP resynthesis was significantly higher in the HMPO2 100% group.This study demonstrates that continuous HMPO2 results in a significant modification of tpO2 compared with SCS, and the degree of tpO2 is positively correlated with the percentage of active oxygenation during HMP. Metabolic profile analyses (ATP resynthesis) suggest that the aerobic mechanism is better supported with higher oxygen levels (50% and 100% oxygenation). [ABSTRACT FROM AUTHOR]

Background: To investigate the accuracy of quantitative blood oxygen level-dependent (qBOLD) magnetic resonance imaging (MRI) in identifying hypoxia within glioblastoma and explore dynamic changes in oxygenation status of glioblastoma with and without metformin administration. Methods: Three healthy and seven C6-bearing rats underwent 7-T qBOLD MRI. Oxygen extraction fraction (OEF) and cerebral metabolism rate of O2 (CMRO2) were calculated from qBOLD data. Tumor tissues were stained using hypoxia-inducible factor-1 α (HIF-1 α ) and pimonidazole. The correlation between the hypoxia markers and corresponding qBOLD-based parameters was analyzed. Six C6-bearing rats were divided into metformin-treated and control groups for a longitudinal study of qBOLD imaging changes, with scans conducted on the 12th, 15th, and 18th day post-tumor implantation. Results: In healthy rats, gray matter showed higher values than white matter in T2, T2*, cerebral blood volume (CBV), and cerebral blood flow (CBF), whereas OEF was lower. Glioblastoma tissues exhibited elevated T2, T2*, CBV, and CBF but decreased OEF and CMRO2 relative to normal-appearing white matter. No significant correlation was found between staining scores from HIF-1 α and pimonidazole. T2* and T2 values were negatively correlated with pimonidazole scores in tumor regions. As the tumor progressed, OEF values increased with intra-tissue variations, whereas CMRO2 decreased. Metformin delayed the reduction of T2 and T2* values, with significant differences in OEF and CMRO2 values compared to controls on day 18. Conclusion: T2* and T2 values were significantly associated with the hypoxia status in glioma. Metformin could potentially mitigate the progression of hypoxia in glioblastoma, which can be tracked by qBOLD parameters. Relevance statement: This study demonstrates the potential of qBOLD parameters in assessing glioma dynamic oxygen metabolism and the efficacy of metformin as an anti-hypoxic agent, providing insights into improving glioblastoma treatment strategies. Key Points: The study investigated qBOLD imaging's accuracy in identifying hypoxia status within glioblastoma. qBOLD effectively assesses hypoxia and its dynamic evolution in glioblastoma. qBOLD parameters assist in identifying a suitable patient demographic for metformin treatment. [ABSTRACT FROM AUTHOR]

The management of composting home bio-waste at the place of their formation leads to several benefits. Among them are: minimising the amount of waste sent to landfills, decreasing the costs associated with transporting them to disposal sites, and reducing the need for new facilities dedicated to this purpose. A further advantage of home composting is the better segregation of waste compared to industrial composting, there is less accidental contamination by plastic, glass, or metal waste, which is a key requirement for a proper biodegradation process. However, despite to many benefits of home composting, the method is still controversial. The first part of the paper briefly characterises the key parameters for an effective home composting process, i.e.: temperature, air porosity, oxygenation, and moisture content. It is also widely considered and discussed the problem of reasons why home composters do not reach the temperature values considered necessary for the sterilisation of waste. Potential needs to reach the same high temperatures in home composting as in industrial composting are also discussed. The next part of the paper presents some technical solutions currently used in home composters to improve the process of biodegradation of waste and to make them easier to use. The final section addresses the quality of home compost and the issues around correctly assessing its maturity and stability. [ABSTRACT FROM AUTHOR]

Liver ischemia‐reperfusion (I/R) injury is a common cause of organ failure, developed by a sudden block in the blood and oxygen supply and subsequent restoration. I/R damage is responsible for acute and chronic rejection after organ transplantation, accounting for 10% of early graft failure. The study investigated the therapeutic properties of fangchinoline in liver injury‐induced rats. The rats were divided into three groups: Sham, I/R without pretreatment, and I/R + 10 mg/kg fangchinoline pretreatment. Blood and liver samples were collected for assays, and an in silico docking analysis was conducted to determine fangchinoline's inhibitory effect. The pretreatment with 10 mg/kg of fangchinoline effectively reduced hepatic marker enzymes such as AST, LDH, and ALT in the serum of rats with liver I/R damage. Fangchinoline treatment significantly reduced interleukin‐8 (IL‐8), IL‐6, and tumor necrosis factor‐α (TNF‐α) in I/R‐induced rats, boosting antioxidants and decreasing MDA. Histopathological studies showed liver injury protection, and fangchinoline inhibited TNF‐α and IL‐6 with improved binding affinity. Fangchinoline has hepatoprotective properties by reducing inflammation in rats with liver I/R damage, as demonstrated in the current study. Hence, it can be an effective salutary agent in preventing liver damage caused by I/R. [ABSTRACT FROM AUTHOR]

Within-individual blood oxygen level-dependent (BOLD) signal variability, intrinsic moment-to-moment signal fluctuations within a single individual in specific voxels across a given time course, is a relatively new metric recognized in the neuroimaging literature. Within-individual BOLD signal variability has been postulated to provide information beyond that provided by mean-based analysis. Synthesis of the literature using within-individual BOLD signal variability methodology to examine various cognitive domains is needed to understand how intrinsic signal fluctuations contribute to optimal performance. This systematic review summarizes and integrates this literature to assess task-based cognitive performance in healthy groups and few clinical groups. Included papers were published through October 17, 2022. Searches were conducted on PubMed and APA PsycInfo. Studies eligible for inclusion used within-individual BOLD signal variability methodology to examine BOLD signal fluctuations during task-based functional magnetic resonance imaging (fMRI) and/or examined relationships between task-based BOLD signal variability and out-of-scanner behavioral measure performance, were in English, and were empirical research studies. Data from each of the included 19 studies were extracted and study quality was systematically assessed. Results suggest that variability patterns for different cognitive domains across the lifespan (ages 7–85) may depend on task demands, measures, variability quantification method used, and age. As neuroimaging methods explore individual-level contributions to cognition, within-individual BOLD signal variability may be a meaningful metric that can inform understanding of neurocognitive performance. Further research in understudied domains/populations, and with consistent quantification methods/cognitive measures, will help conceptualize how intrinsic BOLD variability impacts cognitive abilities in healthy and clinical groups. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the effect of repeated sprint in hypoxia (RSH) training in mask vs. tent system on the physiological parameters associated with the cyclist's performance. Sixteen well-trained cyclists (VO2max 66 ± 5.9 mL/kg/min) participated in a randomised and two parallel groups design. Participants were assigned to different hypoxia methods [RSHMask (n = 8) vs RSHTent (n = 8)]. The sprint number and power output were measured during a repeated sprint test to failure before and after the effect of eight sessions of RSH. In addition, the following physiological parameters were evaluated: oxygen consumption (VO2), heart rate (HR), arterial oxygen saturation (SpO2), muscle oxygen saturation (SmO2), lactate and core temperature (CoreT°). Linear mixed models were used for repeated measures (p value < 0.05), and the effect size (ES) between groups was reported. An inter-individual analysis of participants was also reported. There was an increase in sprint numbers in both groups (ES = 0.167, p = 0.023) and an increase in power output (∑w) in the RSHMask group (ES = 0.095, p = 0.038). The RSHMask group showed improvement in VO2 recovery (ES = 0.096, p = 0.031) and SmO2 desaturation % (ES = 0.112, p = 0.042) compared to the RSHTent group. Likewise, 50% of the participants in RSHTent showed adaptations to withstand higher T°Core (+ 0.45°), and eight participants showed lactate decreases between 2.9 and 3.1 mmol/L (−24%) after RSH in both groups. Generally, RSH improves the cyclist's performance, whether the mask or tent method is used. However, RSHTent has the advantage of causing adaptations in T°Core, whilst RSHMask improves anaerobic performance in the oxygenation of peripheral muscles. [ABSTRACT FROM AUTHOR]

Purpose: Post-exercise passive heating has been reported to augment adaptations associated with endurance training. The current study evaluated the effect of a 4-week remotely administered, post-exercise passive leg heating protocol, using an electrically heated layering ensemble, on determinants of endurance performance. Methods: Thirty recreationally trained participants were randomly allocated to either a post-exercise passive leg heating (PAH, n = 16) or unsupervised training only control group (CON, n = 14). The PAH group wore the passive heating ensemble for 90–120 min/day, completing a total of 20 (16 post-exercise and 4 stand-alone leg heating) sessions across 4 weeks. Whole-body (peak oxygen uptake, gas exchange threshold, gross efficiency and pulmonary oxygen uptake kinetics), single-leg exercise (critical torque and NIRS-derived muscle oxygenation), resting vascular characteristics (flow-mediated dilation) and angiogenic blood measures (nitrate, vascular endothelial growth factor and hypoxia inducible factor 1−α) were recorded to characterize the endurance phenotype. All measures were assessed before (PRE), at 2 weeks (MID) and after (POST) the intervention. Results: There was no effect of the intervention on test of whole-body endurance capacity, vascular function or blood markers (p > 0.05). However, oxygen kinetics were adversely affected by PAH, denoted by a slowing of the phase II time constant; τ (p = 0.02). Furthermore, critical torque–deoxygenation ratio was improved in CON relative to PAH (p = 0.03). Conclusion: We have demonstrated that PAH had no ergogenic benefit but instead elicited some unfavourable effects on sub-maximal exercise characteristics in recreationally trained individuals. [ABSTRACT FROM AUTHOR]

The underlying mechanism for the association between sleep restriction (SR) and unfavorable cognitive outcomes in children and adolescents remains unclear. This study aimed to understand the effect of 5-night experimental SR on magnetic resonance imaging (MRI) measurements of cerebrovascular reactivity (CVR) and cognitive function in adolescents. This randomized crossover study compared two sleep conditions, SR and Control Sleep (CS) in a home setting. Healthy adolescents aged 15–18 years were recruited. The protocol began with two nights of baseline sleep to record participants' habitual sleep duration, followed by the two sleep conditions in the randomly allocated sequence, either SR (6 h in bed for 5 nights) followed by CS (9 h in bed for 5 nights), or the reverse sequence. Their sleep-wake pattern was monitored by an accelerometer and a sleep diary throughout the study period. Cerebral hemodynamics were assessed by hypercapnic challenge blood oxygen level-dependent (BOLD) MRI of CVR. Cognitive function was evaluated by NIH Toolbox Cognitive Battery on the day immediately after each sleep condition. A total of 27 participants (8 males; mean age: 16.8 ± 0.7 years, range 15–18 years) were included in the study. The average sleep duration was significantly reduced in the SR condition compared to the CS condition (320 ± 34 min vs. 426 ± 45 min, p < 0.001). The CVR in the temporal occipital fusiform cortex [adjusted β (95 % CI) = −0.091(-0.010 to −0.172), p = 0.032] and occipital lobe [adjusted β (95 % CI) = −0.087 (−0.002 to −0.172), p = 0.045] was significantly lower following the SR condition when compared to the CS condition. Participants also had lower performance scores in the inhibitory control [adjusted β (95 % CI) = −6.0(−0.9 to −11.0), p = 0.019] and cognitive flexibility [adjusted β (95 % CI) = −6.6 (−1.7 to −11.6), p = 0.008] domains after the SR condition when compared to the CS condition. Short-term SR is associated with poorer cognitive function possibly through reduced cerebral vasodilatory capacity in specific cognitive regions. • Five nights of sleep restriction is linked to decreased cerebrovascular reactivity in adolescents. • Temporal occipital fusiform cortex and occipital lobe are the most affected brain regions. • Inhibitory control and cognitive flexibility were reduced after short-term sleep restriction. • Sleep restriction may reduce cognitive function by impairing cerebrovascular function in specific brain regions. [ABSTRACT FROM AUTHOR]

Objective: This study examines the therapeutic potential of monotropein (Mon) in a rat model of acute pulmonary embolism (APE), aiming to elucidate its mechanistic role and provide new insights for APE treatment. Methods: Thirty Sprague Dawley (SD) rats were randomly assigned to five groups (n = 6 per group): sham, Mon (40 mg/kg), APE, APE + 20 mg/kg Mon, and APE + 40 mg/kg Mon. APE was induced via autologous thrombus infusion in all groups except sham and Mon-only groups. We assessed blood gas parameters, lung wet/dry weight (W/D) ratio, and oxidative stress markers. Additionally, excised lung tissues underwent evaluation for serum inflammatory factors via ELISA, apoptotic cells via TUNEL assay, and protein expression via Western blot. Results: Compared to the sham group, APE-induced rats exhibited significantly elevated blood oxygen levels and increased pro-inflammatory factors, including interleukin (IL)-1β, IL-6, tumor necrosis factor (TNF)-α, and IL-8. Mon treatment effectively mitigated these APE-induced changes, reducing blood oxygen concentration and downregulating IL-1β and TNF-α levels. Furthermore, Mon demonstrated anti-apoptotic effects by decreasing cleaved caspase-3 and Bax protein levels while upregulating Bcl-2 expression. Mon also suppressed nuclear factor-κB (NF-κB) activation by inhibiting the phosphorylation levels of p65/RelA and IκBα proteins, while the total protein level of IκBα was increased with Mon treatment. Conclusion: Mon effectively ameliorated lung tissue injury in APE rats by inhibiting apoptosis, attenuating inflammatory responses, and alleviating oxidative stress. These beneficial effects appear to be mediated through modulation of the NF-κB pathway, suggesting Mon as a promising therapeutic candidate for APE treatment. [ABSTRACT FROM AUTHOR]