Evaluating the relationship between ocular blood flow and systemic organ blood flow in hemorrhagic shock using a rabbit model.

This study aimed to investigate the feasibility of utilizing noninvasive ocular blood flow measurements as potential indicators of systemic circulation in rabbits experiencing hemorrhagic shock. Using Laser speckle flowgraphy, ocular blood flow indices, relative flow volume (RFV), and mean blur rate in the choroidal area (MBR-CH) were assessed in New Zealand White rabbits (n = 10) subjected to controlled blood removal and return. Hemodynamic parameters and biochemical markers were monitored alongside ocular circulation during blood removal and return phases. Additionally, correlations between ocular parameters and systemic indices were examined. The results indicated that RFV and MBR-CH exhibited significant correlations with renal and intestinal blood flows, with stronger correlations observed during blood removal. Additionally, ocular blood flow changes closely mirrored systemic dynamics, suggesting their potential as real-time indicators of shock progression and recovery. These findings indicate that ocular blood flow measurements may serve as real-time indicators of the systemic circulation status during hemorrhagic shock, offering potential insights into shock management and guiding tailored interventions. Thus, noninvasive ocular blood flow evaluation holds promise as an innovative tool for assessing systemic circulation dynamics during hemorrhagic shock.

Quantitative Analysis of Lumbar Disc Bulging in Patients with Lumbar Spinal Stenosis: Implication for Surgical Outcomes of Decompression Surgery.

This study aimed to quantitatively assess disc bulging using computed tomography (CT) in patients with lumbar spinal stenosis (LSS) and to examine whether disc bulging affects the surgical outcomes of patients with LSS after posterior decompression surgery. Sixty-three patients who underwent posterior decompression surgery for LSS were included. The extent of disc bulging was evaluated as the percentage of the extended area of the disc against the endplate area (%EAD) on axial CT images. The participants completed the following clinical outcome assessments (COAs) preoperatively and 12 months postoperatively: the JOA Back Pain Evaluation Questionnaire (JOABPEQ), Oswestry Disability Index (ODI), and Roland-Morris Disability Questionnaire (RDQ). The mean %EAD of 315 intervertebral discs was 18.9 ± 8.0. The %EAD was highest at L4/L5, followed by L3/L4, L2/L3, L1/L2, and L5/S1. The %EAD of the surgical level showed no significant correlation with all the preoperative COAs, but it had significant correlation with lumbar function, walking ability, social function domains of the JOABPEQ, ODI score, and RDQ score 12 months postoperatively. %EAD was significantly associated with the postoperative score in the walking ability domain of the JOABPEQ. %EAD affects postoperative clinical outcomes, including low back pain-related quality of life after decompression surgery.

Does locomotive syndrome severity predict future fragility fractures in community-dwelling women with osteoporosis?

OBJECTIVES: We investigated whether the locomotive syndrome (LS) severity affects future fragility fractures in osteoporosis patients. METHODS: In this retrospective cohort study, 315 women with osteoporosis (mean follow-up period, 2.8 years) were reviewed, of whom 244 were included in the analysis. At baseline, we obtained medical information, bone mineral density of the lumbar spine and femoral neck, and sagittal vertical axis. Additionally, LS risk was assessed using the two-step test, stand-up test, and 25-question geriatric locomotive function scale scores. The LS risk test results were used to classify LS severity, which was rated on a 4-point scale from stage 0 (robust) to 3 (worsening). Cox proportional hazards regression analysis was used to determine the association of the severity with future fragility fracture. RESULTS: Fragility fractures occurred in 37 of 315 participants (11.8%). This study showed that sagittal vertical axis (hazard ratio = 1.014; 95% confidence interval, 1.005-1.023; p value = 0.003) and LS severity (hazard ratio =1.748; 95% confidence interval, 1.133-2.699; p = 0.012) were independent risk factors for incidence of fragility fracture. CONCLUSIONS: This study revealed the LS severity to predicted fragility fractures. We suggested that the progression of LS associated with osteoporosis increases the fracture risk.

Preseason Prognostic Factors for Injuries and Match Loss in Collision Sports: A Systematic Review.

This study aimed to identify which preseason factors had strong evidence of risks for physical injury during the season of collision sports including rugby, American football, and Australian rules football using qualitative synthesis. Pubmed, EMBASE, MEDLINE, SPORTDiscus, Scopus, and the Cochrane Library were reviewed. Eligibility criteria for selecting studies were: studies involving the collision sports; prospective cohort studies; and studies with outcomes of relative risks, odds ratios, and correlations between players' preseason conditions and injury during the season. The risk of bias based on the Scottish Intercollegiate Guidelines Network quality checklists for cohort studies was assessed in 57 studies. The current study identified strong evidence that 1) anthropometric characteristics (body mass index and estimated mass moment of inertia of the body around a horizontal axis through the ankle), which are calculated with weight and height; 2) physical function, in particular for the trunk and lower limb (trunk-flexion hold and wall-sit hold); and 3) Oswestry Disability Index disability, which is a patient-reported outcome measure for disability due to low back pain, were positive prognostic factors for injury during the collision sports season, regardless of playing experience.

Validation of Wearable Device Consisting of a Smart Shirt with Built-In Bioelectrodes and a Wireless Transmitter for Heart Rate Monitoring in Light to Moderate Physical Work.

Real-time monitoring of heart rate is useful for monitoring workers. Wearable heart rate monitors worn on the upper body are less susceptible to artefacts caused by arm and wrist movements than popular wristband-type sensors using the photoplethysmography method. Therefore, they are considered suitable for stable and accurate measurement for various movements. In this study, we conducted an experiment to verify the accuracy of our developed and commercially available wearable heart rate monitor consisting of a smart shirt with bioelectrodes and a transmitter, assuming a real-world work environment with physical loads. An exercise protocol was designed to light to moderate intensity according to international standards because no standard exercise protocol for the validation simulating these works has been reported. This protocol includes worker-specific movements such as applying external vibration and lifting and lowering loads. In the experiment, we simultaneously measured the instantaneous heart rate with the above wearable device and a Holter monitor as a reference to evaluate mean absolute percentage error (MAPE). The MAPE was 0.92% or less for all exercise protocols conducted. This value indicates that the accuracy of the wearable device is high enough for use in real-world cases of physical load in light to moderate intensity tasks such as those in our experimental protocol. In addition, the experimental protocol and measurement data devised in this study can be used as a benchmark for other wearable heart rate monitors for use for similar purposes.

Stress-dependent cell stiffening by tardigrade tolerance proteins that reversibly form a filamentous network and gel.

Tardigrades are able to tolerate almost complete dehydration by entering a reversible ametabolic state called anhydrobiosis and resume their animation upon rehydration. Dehydrated tardigrades are exceptionally stable and withstand various physical extremes. Although trehalose and late embryogenesis abundant (LEA) proteins have been extensively studied as potent protectants against dehydration in other anhydrobiotic organisms, tardigrades produce high amounts of tardigrade-unique protective proteins. Cytoplasmic-abundant heat-soluble (CAHS) proteins are uniquely invented in the lineage of eutardigrades, a major class of the phylum Tardigrada and are essential for their anhydrobiotic survival. However, the precise mechanisms of their action in this protective role are not fully understood. In the present study, we first postulated the presence of tolerance proteins that form protective condensates via phase separation in a stress-dependent manner and searched for tardigrade proteins that reversibly form condensates upon dehydration-like stress. Through a comprehensive search using a desolvating agent, trifluoroethanol (TFE), we identified 336 proteins, collectively dubbed "TFE-Dependent ReversiblY condensing Proteins (T-DRYPs)." Unexpectedly, we rediscovered CAHS proteins as highly enriched in T-DRYPs, 3 of which were major components of T-DRYPs. We revealed that these CAHS proteins reversibly polymerize into many cytoskeleton-like filaments depending on hyperosmotic stress in cultured cells and undergo reversible gel-transition in vitro. Furthermore, CAHS proteins increased cell stiffness in a hyperosmotic stress-dependent manner and counteract the cell shrinkage caused by osmotic pressure, and even improved the survival against hyperosmotic stress. The conserved putative helical C-terminal region is necessary and sufficient for filament formation by CAHS proteins, and mutations disrupting the secondary structure of this region impaired both the filament formation and the gel transition. On the basis of these results, we propose that CAHS proteins are novel cytoskeleton-like proteins that form filamentous networks and undergo gel-transition in a stress-dependent manner to provide on-demand physical stabilization of cell integrity against deformative forces during dehydration and could contribute to the exceptional physical stability in a dehydrated state.

Association between postextubation dysphagia and physical function in survivors of critical illness: A retrospective study.

BACKGROUND & AIMS: Dysphagia following endotracheal intubation, also known as postextubation dysphagia (PED), is generally observed in survivors of critical illness. However, its association with physical function remains relatively unexplored. This study aimed to investigate the association between PED and physical function in patients after intensive care. METHODS: This is a single-center retrospective observational study. Medical records of adult patients who required emergency admission and were intubated and mechanically ventilated were retrospectively reviewed. Swallowing and physical function were assessed using the Food Intake Level Scale (FILS) and functional status score for the intensive care unit (FSS-ICU) at discharge, respectively. Multivariable linear and logistic regression analyses were used to analyze the association between dysphagia and physical dysfunction at discharge. RESULTS: A total of 103 patients (63 men and 40 women) with a mean age of 67.3 years were enrolled. PED was observed in 20 patients (19.4%) at hospital discharge. The FILS score at hospital discharge was significantly and independently associated with the FSS-ICU (ß = 0.458, p < 0.001); however, the FILS score was not an independent risk factor for non-home discharge (95% confidence interval, 0.547-1.160). CONCLUSIONS: PED is significantly associated with physical dysfunction at discharge in survivors of critical illness. PED should be considered as a component of post-intensive care syndrome, and early intervention to prevent and improve swallowing dysfunction may be necessary.

Real-Time Evaluation of Regional Arterial Stiffening, Resistance, and Ocular Circulation During Systemic Administration of Adrenaline in White Rabbits.

Purpose: To evaluate continuous variations of ocular microcirculation by laser speckle flowgraphy and those of regional stiffening by pulse wave velocity (PWV) and vascular resistance under systemic adrenaline administration in rabbits. Methods: Six 16-week-old male rabbits were evaluated. The mean blur rates in the retinal vessel (MBR-RV) and choroid (MBR-CH) were measured. We assessed blood pressure (BP), femoral and carotid vascular resistance, and the heart-ankle (ha)-PWV, heart-femoral (hf)-PWV, and femoral-ankle (fa)-PWV. Adrenaline (100, 300, and 1000 ng/kg) was intravenously administered over a 10-minute period during which the parameters were measured simultaneously every 2 minutes. Results: The MBR-RV and MBR-CH values were dose-dependently increased by the adrenaline in parallel with increased BP. At the load of 100 ng/kg adrenaline, the ΔMBR-RV and ΔMBR-CH showed positive correlations with the variation rate in mean arterial blood pressure. Also, the variation rate in carotid vascular resistance and the Δfa-PWV and Δhf-PWV were significantly positively correlated with both the ΔMBR-RV and ΔMBR-CH. At the 300-ng/kg phase, the correlations between the Δha-PWV and both ΔMBR-RV and ΔMBR-CH were canceled; instead, the Δhf-PWV showed a significant negative correlation with the ΔMBR-RV and ΔMBR-CH. At the 1000-ng/kg phase, Δha-PWV again showed significant positive correlations with the ΔMBR-RV and ΔMBR-CH. Conclusions: These results indicate the possibility that under a systemic administration of adrenaline in rabbits, not only the BP value but also the vascular resistance and arterial function are related to the variation in ocular microcirculation. Translational Relevance: A real-time evaluation system of systemic regional arterial function and ocular microcirculation in rabbits was developed.

Microtubule inhibitors identified through nonbiased screening enhance DNA transfection efficiency by delaying p62-dependent ubiquitin recruitment.

Ectopic gene expression is an indispensable tool in biology and medicine, but is often limited by the low efficiency of DNA transfection. We previously reported that depletion of the autophagy receptor p62/SQSTM1 enhances DNA transfection efficiency by preventing the degradation of transfected DNA. Therefore, p62 is a potential target for drugs to increase transfection efficiency. To identify such drugs, a nonbiased high-throughput screening was applied to over 4,000 compounds from the Osaka University compound library, and their p62 dependency was evaluated. The top-scoring drugs were mostly microtubule inhibitors, such as colchicine and vinblastine, and all of them showed positive effects only in the presence of p62. To understand the p62-dependent mechanisms, the time required for p62-dependent ubiquitination, which is required for autophagosome formation, was examined using polystyrene beads that were introduced into cells as materials that mimicked transfected DNA. Microtubule inhibitors caused a delay in ubiquitination. Furthermore, the level of phosphorylated p62 at S405 was markedly decreased in the drug-treated cells. These results suggest that microtubule inhibitors inhibit p62-dependent autophagosome formation. Our findings demonstrate for the first time that microtubule inhibitors suppress p62 activation as a mechanism for increasing DNA transfection efficiency and provide solutions to increase efficiency.

The influence of hemorrhagic shock on ocular microcirculation by obtained by laser speckle flowgraphy in a white rabbit model.

PURPOSE: To clarify the continuous changes in the retinal vessels' and choroid's microcirculation during hemorrhagic shock and resuscitation in a rabbit model. METHODS: Hemorrhagic shock by the removal of blood (30 mL) and resuscitation by a blood-return technique was induced in anesthetized male New Zealand White rabbits (n = 10). We evaluated the retinal vessel blood flow (relative flow volume: RFV) and choroidal blood flow (mean blur rate in the choroid area: MBR-CH) by laser speckle flowgraphy (LSFG), with simultaneous measurements of systemic hemodynamics and laboratory parameters. RESULTS: RFV and MBR-CH showed significant decreases immediately after the initiation of blood removal and recovered by blood return. The lactate concentration tended to increase from baseline by the blood-removal operation, and it was significantly higher at the end of observation period. The %RFV and %MBR-CH each showed a significant positive correlation with mean arterial blood pressure, cardiac output, carotid blood flow, and central venous pressure. %RFV showed a significant positive correlation with %central venous oxygen saturation and negatively correlated with %lactate. The %hemoglobin did not show a significant correlation with %RFV or %MBR-CH. CONCLUSION: This rabbit hemorrhagic shock model confirmed that ocular microcirculation measurements by LSFG feasibly reflect variations in systemic hemodynamics during hemorrhagic shock and recovery.

Stand-up test predicts occurrence of non-traumatic vertebral fracture in outpatient women with osteoporosis.

INTRODUCTION: The purpose of this retrospective study was to clarify the incidence of non-traumatic vertebral fracture among outpatient women with osteoporosis and to determine whether the stand-up test predicted the occurrence of non-traumatic vertebral fracture. MATERIALS AND METHODS: A total of 242 postmenopausal women over 60 years of age who received outpatient osteoporosis treatment at our hospital between November 2013 and July 2020 were longitudinally evaluated in this study. We obtained medical information and radiographic parameters, including sagittal vertical axis, thoracic kyphosis, pelvic incidence, lumbar lordosis, pelvic tilt, and sacral slope at baseline. Additionally, we measured physical parameters, including height, weight, body mass index, lumbar bone mineral density, visual analog scale score for pain, and the stand-up test. RESULTS: Vertebral fractures occurred in 20 of 242 participants (8.3%), and accounted for 48.8% the 41 total fractures in the study group. Among vertebral fractures, eight (40.0%) were traumatic, resulting from falls, and 12 (60.0%) were non-traumatic. Cox multivariate logistic regression analysis adjusted for age, body mass index, lumbar bone mineral density, and the time to non-traumatic vertebral fracture showed that the sagittal vertical axis (HR = 1.013, 95% CI 1.001-1.026), stand-up test score (HR = 3.977, 95% CI 1.156-13.683), and presence of difficulty with standing from a 20-cm-high seat using both legs (HR = 3.329, 95% CI 1.625-6.82) were independent risk factors for the occurrence of non-traumatic vertebral fracture. CONCLUSION: The stand-up test may be useful as a simple screening tool for non-traumatic vertebral fracture in patients with osteoporosis.

The effects of trunk endurance training on running kinematics and its variability in novice female runners.

The functional importance of trunk muscle strength for running movement is widely recognised, but the kinematic effects of undertaking specific training are unclear. This study investigated the change in joint angle and its variability during running following trunk muscle training. Eighteen young female and novice runners participated. Using Plug-in-gait model with infrared markers attached to the body surface, the lower limb and lumber angles during running were measured, and the variability was examined by calculating the coefficient variation and Lyapunov exponent. Measurements of trunk endurance were also performed. Over four weeks of training, the subjects performed trunk muscle endurance trainings three times a week. Following this intervention, trunk endurance was found to have significantly increased. The Lyapunov exponent of lumbar flexion-extension angle also significantly increased. Moreover, a decreased range of the ankle angle and increased range of the hip angle were observed following the training. These results demonstrate that the trunk training promoted adjustments to lumbar movement and altered the movement patterns of the participants' lower limbs during running.

Low-Noise Photoplethysmography Sensor Using Correlated Double Sampling for Heartbeat Interval Acquisition.

This study designs a low-power photoplethysmography (PPG) sensor based on the error compensation method for heartbeat interval acquisition. To perform heartbeat monitoring in daily life, it is necessary to obtain long-term and accurate heartbeat interval data with low power consumption, because of the limited size and battery capacity of the PPG sensor. Effective reduction in the power consumption of the sensor requires the duty-cycled LEDs and lowering pulse repetition frequency (PRF), i.e., decreasing the sampling rate. However, these methods reduce the accuracy of the heartbeat interval measurement because of signal-to-noise ratio (SNR) degradation and sampling errors. We propose an algorithm for heartbeat interval error compensation and incorporate a low-noise readout circuit to improve SNR. The readout circuit uses current integration to achieve low duty-cycle LED driving. A correlated double sampling (CDS) is introduced to minimize the random noise arising from the switching operation of the integration circuit. An error compensation method based on the PPG waveform similarity is also introduced using the autocorrelation and linear interpolation. The measurement results obtained from nine subjects show that a total current consumption of 28.2 µA is achieved with a 20-Hz PRF and 0.3% LED duty cycle. The proposed design effectively reduces the mean absolute error (MAE) of the heartbeat interval to an average of 6.2 ms.

Angiotensin II acutely increases arterial stiffness as monitored by cardio-ankle vascular index (CAVI) in anesthetized rabbits.

The cardio-ankle vascular index (CAVI) has been established as a stiffness indicator from thoracic aorta to tibial arteries. To better understand physiological regulatory factors for the arterial stiffness, we assessed effects of angiotensin II and adrenaline on the CAVI in anesthetized rabbits. A hypertensive dose of angiotensin II (300 ng/kg, i.v.) increased the CAVI as well as the heart-ankle pulse wave velocity (haPWV). On the other hand, although a hypertensive dose of adrenaline (1000 ng/kg, i.v.) increased the haPWV, it did not affect the CAVI. These results suggest that angiotensin II may act as a regulatory factor for arterial stiffness.

A 5-ms Error, 22-µA Photoplethysmography Sensor using Current Integration Circuit and Correlated Double Sampling.

This paper presents a low-power Photoplethysmography (PPG) sensing method. The PPG is commonly used in recent wearable devices to detect cardiovascular information including heartbeat. The heartbeat is useful for physical activity and stress monitoring. However, the PPG circuit consumes large power because it consists of LED and photodiode. To reduce its power consumption without accuracy degradation, a cooperative design of circuits and algorithms is proposed in this work. A straightforward way to reduce the power is intermittent driving of LED, but there is a disadvantage that the signal is contaminated by a noise while circuit switching. To overcome this problem, we introduce correlated double sampling (CDS) method, which samples an integration circuit output twice with short intervals after the LED turns on and uses the difference of these voltage. Furthermore, an up-conversion method using linear interpolation, and an error correction using autocorrelation are introduced. The proposed PPG sensor, which consists of the LED, the photodiode, the current integration circuit, a CMOS switch, an A/D converter, and an MCU, is prototyped. It is evaluated by actual measurement with 22-year-old subject. The measurement results show that 22-µA total current consumption is achieved with 5-ms mean absolute error.

Anti-de Sitter Space from Optimization of Path Integrals in Conformal Field Theories.

We introduce a new optimization procedure for Euclidean path integrals, which compute wave functionals in conformal field theories (CFTs). We optimize the background metric in the space on which the path integration is performed. Equivalently, this is interpreted as a position-dependent UV cutoff. For two-dimensional CFT vacua, we find the optimized metric is given by that of a hyperbolic space, and we interpret this as a continuous limit of the conjectured relation between tensor networks and Anti-de Sitter (AdS)/conformal field theory (CFT) correspondence. We confirm our procedure for excited states, the thermofield double state, the Sachdev-Ye-Kitaev model, and discuss its extension to higher-dimensional CFTs. We also show that when applied to reduced density matrices, it reproduces entanglement wedges and holographic entanglement entropy. We suggest that our optimization prescription is analogous to the estimation of computational complexity.

Thermal Molding of Organic Thin-Film Transistor Arrays on Curved Surfaces.

In this work, a thermal molding technique is proposed for the fabrication of plastic electronics on curved surfaces, enabling the preparation of plastic films with freely designed shapes. The induced strain distribution observed in poly(ethylene naphthalate) films when planar sheets were deformed into hemispherical surfaces clearly indicated that natural thermal contraction played an important role in the formation of the curved surface. A fingertip-shaped organic thin-film transistor array molded from a real human finger was fabricated, and slight deformation induced by touching an object was detected from the drain current response. This type of device will lead to the development of robot fingers equipped with a sensitive tactile sense for precision work such as palpation or surgery.

Continuous Multiscale Entanglement Renormalization Ansatz as Holographic Surface-State Correspondence.

We present how the surface-state correspondence, conjectured by Miyaji and Takayanagi, works in the setup of AdS(3)/CFT(2) by generalizing the formulation of a continuous multiscale entanglement renormalization group ansatz. The boundary states in conformal field theories play a crucial role in our formulation and the bulk diffeomorphism is naturally taken into account. We give an identification of bulk local operators which reproduces correct scalar field solutions on AdS(3) and bulk scalar propagators. We also calculate the information metric for a locally excited state and show that it reproduces the time slice of AdS(3).

Distance between Quantum States and Gauge-Gravity Duality.

We study a quantum information metric (or fidelity susceptibility) in conformal field theories with respect to a small perturbation by a primary operator. We argue that its gravity dual is approximately given by a volume of maximal time slice in an anti-de Sitter spacetime when the perturbation is exactly marginal. We confirm our claim in several examples.

Cross-sectional laser Doppler velocimetry with nonmechanical scanning of points spatially encoded by multichannel serrodyne frequency shifting.

A laser Doppler velocimeter (LDV) using nonmechanical scanning of multiple points spatially encoded by multichannel serrodyne frequency shifting is proposed for cross-sectional velocity distribution measurement. In the proposed LDV, nonmechanical scanning using wavelength change and simultaneous multipoint measurement using spatial encoding are combined. The use of a LiNbO3 phase-shifter array for multichannel serrodyne modulation makes it possible to simplify the generation of a spatially encoded beam array. An experiment was performed using a sensor probe setup with a six-channel beam array. The results indicate that two-dimensional velocity distribution measurement was successfully demonstrated.