Changes In Blood Oxygen Saturation Research Articles

Assessing myocardial microvascular reactivity with a novel MRI imaging approach as an early biomarker of diabetic heart failure

Abstract Introduction Microvascular dysfunction (mvD), and more specifically coronary microvascular disease (CMD), has been implicated as the primary hallmark of diabetic cardiomyopathy and HFpEF, afflicting millions of people worldwide. The onset and progression of microvascular disease is driven by vascular inflammation and is characterized by vascular smooth muscle cell thickening and impaired vasomodulation, both of which ultimately reduce perfusion and damage tissue. To meet metabolic demands, the body recruits additional assistance from our microvascular reserve, which is diminished during stress, thus resulting in a dampened vasomodulatory response to stimuli. Diagnosing mvD in the myocardium, therefore, requires a non-invasive method to measure vasomodulation or, more precisely, changes in microvascular blood volume. Purpose Current clinical imaging platforms lack the ability to detect vasomodulation in a sensitive and specific manner. Because of this shortcoming, there is also no literature sex comparison of cardiac microvascular reactivity in response to stress in diabetics. This work aims to address this technology and knowledge gap by developing and demonstrating a novel MRI technique for the specific assessment of vasomodulation without confounding influences from changes in blood oxygen saturation, hematocrit, or flow. Methods Elevated CO2 is a safe and reliable vasodilatory stimulus and is effective in differentiating healthy from diseased vasculature. 10% CO2 was mixed with 21% oxygen and directed into an intubated rat. A blood-pool T1 contrast agent (Ablavar) was injected intravenously as a bolus (0.3mmol/kg) followed by a saline flush, to saturate the blood volume fraction, eliminating sensitivity to molecular oxygen and producing changes in T1 dominated by the blood volume fraction. The extended residency time of Ablavar, which stems from protein binding, allows a prolonged period of stable T1 signal enhancement (approx. 40 minutes). Results Exposure to 10% CO2, a known cardiac vasodilator, elicited conflicting results when compared across sexes. Young female rats demonstrated a strong vasodilatory response within 10 minutes of hypercapnic exposure, quantified through the drastic reduction in T1, while their male counterparts exhibited little to no change. When reverting to room air following 10 minutes of CO2, both male and female animals exhibited strong vasoconstriction. Young pre-diabetic female rats exhibited a blunted response when exposed to 10% CO2, losing their ability to vasodilate and constrict. Conclusion This work described a novel MRI diagnostic tool for highly specific assessment of microvascular vasomodulation and demonstrated a greater vasodilatory response to hypercapnic stimuli in healthy female rats compared to male, along with blunted response in diabetic females. This non-invasive technology will be valuable for early diagnosis of cardiac disease in patients predisposed to developing mvD.T1 myocardial microvascular reactivityBlunted pre-diabetic female stress-CMR

Design and Implementation of Health and Risk Level Assessment for Socially Disadvantaged Patients

The platform developed in this study provides users with mental and physical health status monitoring services. Recently, it has been difficult for people with various respiratory diseases and mental health conditions to receive regular examinations/observation from specialized medical institutions. Therefore, in this study, because the need for the continuous health status measurement/monitoring of subjects was recognized, a device for constantly monitoring trends and changes in blood oxygen saturation was developed to ensure safety. Oxygen saturation below 90 indicates an emergency. In addition, we conducted a hypothesis test for analyzing the relationship between sensor data and depression and anxiety. The sensor data used in the research were location, gyroscope metrics, touch, data usage, and sleep mode from a smartphone. Correlation analysis and multiple regression analysis were conducted to analyze the relationship between the collected sensor data and depression and anxiety. As a result of the research, it was found that among the general characteristics, income, location, sleep duration, and gyroscope were found to have a negative effect on depression and anxiety, whereas touch was shown to have a positive (+) effect. It was confirmed that sensor data measured over runtime can be used as information that can explain users’ depression and anxiety.

A mechanistic computational framework to investigate the hemodynamic fingerprint of the blood oxygenation level-dependent signal.

Blood oxygenation level-dependent (BOLD) functional magnetic resonance imaging (fMRI) is one of the most used imaging techniques to map brain activity or to obtain clinical information about human cortical vasculature, in both healthy and disease conditions. Nevertheless, BOLD fMRI is an indirect measurement of brain functioning triggered by neurovascular coupling. The origin of the BOLD signal is quite complex, and the signal formation thus depends, among other factors, on the topology of the cortical vasculature and the associated hemodynamic changes. To understand the hemodynamic evolution of the BOLD signal response in humans, it is beneficial to have a computational framework available that virtually resembles the human cortical vasculature, and simulates hemodynamic changes and corresponding MRI signal changes via interactions of intrinsic biophysical and magnetic properties of the tissues. To this end, we have developed a mechanistic computational framework that simulates the hemodynamic fingerprint of the BOLD signal based on a statistically defined, three-dimensional, vascular model that approaches the human cortical vascular architecture. The microvasculature is approximated through a Voronoi tessellation method and the macrovasculature is adapted from two-photon microscopy mice data. Using this computational framework, we simulated hemodynamic changes-cerebral blood flow, cerebral blood volume, and blood oxygen saturation-induced by virtual arterial dilation. Then we computed local magnetic field disturbances generated by the vascular topology and the corresponding blood oxygen saturation changes. This mechanistic computational framework also considers the intrinsic biophysical and magnetic properties of nearby tissue, such as water diffusion and relaxation properties, resulting in a dynamic BOLD signal response. The proposed mechanistic computational framework provides an integrated biophysical model that can offer better insights regarding the spatial and temporal properties of the BOLD signal changes.

The Effects of the Myobrace® System on Peripheral Blood Oxygen Saturation (SpO2) in Patients with Mixed Dentition with Oral Dysfunction.

Myobrace® is an orthodontic device that has the purpose of correcting oral dysfunctions, thus predisposing the physiological growth of the jaws, aligning teeth, and optimizing face development. This device is usually associated with Myobrace® Activities to reach this target. Considering the lack of studies in the literature about peripheral blood oxygen saturation (SpO2) and the use of preformed oral devices, the aim of this study is to quantify the change in blood oxygen saturation (SpO2) in patients treated with the Myobrace® System in mixed dentition. In this study, 23 children (11 females and 12 males) were involved, who were affected by different oral dysfunctions and were treated with a Myobrace®. Blood oxygen saturation measurements were taken at baseline and after every four months for a year. The SpO2 measurements were taken in the rest position and with a closed mouth for a total of 12 min-6 min with and 6 min without the Myobrace® oral device. All data points were anonymized and recorded on an Excel spreadsheet. A statistical analysis was carried out. Therapy with a Myobrace® in patients with mixed dentition resulted in a statistically significant increase in oxygen saturation. In particular, in patients with a closed mouth, a statistically significant increase in oxygen saturation was observed, bringing it from 97.66% to 99.00%, while in the rest position, the increase was from 98.03% to 99.07%. The use of Myobrace® devices in patients with mixed dentition could lead to a significant improvement in blood oxygen saturation.

Design and application of wrist restraint gloves suitable for patients with agitation

Patients in the intensive care unit (ICU) often need to have various catheters placed on their bodies due to their severe condition. In order to prevent the occurrence of unplanned extubation, patients' hands should be restrained appropriately. The current restraint gloves used in clinical practice have problems such as improper restraint, easy falling off of oxygen saturation monitoring probes, and pressure injury of hands. Therefore, department of critical care medicine, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine designed a wrist restraint glove suitable for restless patients, and obtained the national utility model patent (ZL 2020 2 1612453.7). The device is composed of restraint gloves and restraint rings, which can not only restrain patients, but also continuously monitor the changes of blood oxygen saturation in patients with restfulness. This device is convenient to use, low cost, comfortable to wear, and can prevent the occurrence of device-related pressure injuries, which is suitable for clinical application.

Sleep quality and polysomnographic changes in patients with chronic pain with and without central sensitization signs

BackgroundInsufficient sleep is common nowadays and it can be associated with chronic pain. ObjectiveTo describe the main polysomnographic findings in patients with chronic musculoskeletal pain and to estimate the association between sleep quality, polysomnography variables and chronic musculoskeletal pain. MethodsThis cross-sectional research analyzed a database from polysomnography type 1 exams results and then collected data via an electronic form from these patients. The form collected sociodemographic data and presented clinical questionnaires for measuring sleep quality, sleepiness, pain intensity and central sensitization signs. Pearson's correlation coefficient and odds ratio were used to estimate the associations. ResultsThe mean age of the respondents was 55.1 (SD 13.4) years. The mean score of the Central Sensitization Inventory showed signs of central sensitization (50.1; SD 13.4) in the participants. Most patients (86%) had 1 or more nocturnal awakenings, 90% had one or more episodes of sleep apnea, 47% had Rapid Eye Movement sleep phase latency greater than 70–120 min and the mean sleep efficiency among all participants was 81.6%. The Pittsburgh Sleep Quality Index score was correlated with the CSI score (r = 0.55; 95% CI: 0.45, 0.61). People with central sensitization signs have 2.6 times more chance to present sleep episodes of blood oxygen saturation below 90% (OR = 2.62; 95% CI:1.23, 6.47). ConclusionMost people with central sensitization signs had poor sleep quality, night waking episodes and specific disturbances in sleep phases. The findings showed association between central sensitization, sleep quality, nocturnal awakening, and changes in blood oxygen saturation during sleep.

APPswe /PS1ΔE9 mice exhibit low oxygen saturation and alterations of erythrocytes preceding the neuropathology and cognitive deficiency during Alzheimer's disease.

The molecular mechanism underlying Alzheimer's disease (AD) pathologies remains unclear. The brain is extremely sensitive to oxygen deprivation, and brief interruptions in oxygen supply may lead to permanent brain damage. The objective here was to access the red blood cell (RBC) physiological alterations and the changes in blood oxygen saturation of an AD model as well as to explore the possible mechanism underlying these pathologies. We used female APPswe /PS1ΔE9 mice as AD models. Data were collected at the age of 3, 6, and 9 months. In addition to examining classic features of AD, namely cognitive deficiency and Aβ depositions, 24 h blood oxygen saturation was monitored by Plus oximeters in real time. In addition, RBC physiological parameters were measured by blood cell counter using peripheral blood from the epicanthal veins. Furthermore, in the mechanism investigations, the expression of phosphorylated band 3 protein was examined by a series of Western blot analyses, and the levels of soluble Aβ40 and Aβ42 on the membrane of RBCs were determined by ELISA. Our results showed that the blood oxygen saturation in the AD mice was significantly reduced as early as at 3 months of age, preceding the neuropathological changes and cognitive impairments. Meanwhile, the expression of phosphorylated band 3 protein and levels of soluble Aβ40 and Aβ42 were all elevated in the erythrocytes of the AD mice. APPswe /PS1ΔE9 mice exhibited decreased oxygen saturation together with reduced RBC counts and hemoglobin concentrations at the early stage, which may aid in the development of predictive markers for AD diagnosis. The increased expression of band 3 protein and elevated Aβ40 and Aβ42 levels may contribute to the deformation of RBCs and, in turn, cause the subsequent AD development.

EFFECT OF MASSOTHERAPY ON THE FATIGUE RECOVERY USING THE SMART MASSAGE CHAIR: A RANDOMIZED CONTROLLED TRIAL

Objective: This study was envisaged to scientifically analyze the efficacy of the massage chair in reducing the fatigue using the heart rate variability (HRV) and fatigue self-assessment scale (FSAS) in a randomized clinical trial. Methods: 240 fatigue volunteers were divided into the massage chair intervention group and the control group using a completely randomized method. The kneading, pressing, tapping, and flapping techniques in the smart massage chair were used to intervene on the volunteers. The FSAS, HRV, and blood oxygen saturation changes were observed before and after the intervention, and the effect of massage in the smart massage chair to relieve fatigue was explored. Results: The overall exhaustion, mental fatigue, and physical fatigue scores of the FSAS were statistically significant (P < 0.05) before and after the intervention. After the intervention, the overall fatigue, mental fatigue, and physical fatigue scores of the experimental group were significantly lower than those of the control group. The HRVhf, HRVlf, and HRVlf/hf in HRV before and after the intervention between the two groups were statistically significant (P < 0.05), and the HRVhf values of the two groups were significantly increased after the intervention. The HRVlf value was significantly reduced, and the HRVlf value of the control group was increased. After the intervention, the HRVlf/hf value of the experimental group was significantly reduced, and the HRVlf/hf value of the control group increased. There were no significant differences in the HR and SpO2 values (P > 0.05). Conclusion: The massaging approach of the smart massage chair significantly reduced the tiredness scale score of the volunteers, reduced the sympathetic nerve excitability, and increased parasympathetic nerve excitability. The results indicate that the smart massage chair can be used as an effective method for short-term fatigue recovery.

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PREFACE

Potential benefits of Qi Gong meditation in quantifiable physiology: A five-year longitudinal observation

Qi Gong is a mind-and-body intervention to improve health and relieve disease conditions, which has been practiced for thousands of years. Lack of quantitative measures to monitor the quality and progress of Qi Gong practice has hindered the high-quality study to evaluate its health benefits. To develop such quantitative measures, vital sign changes in Qi Gong meditation practice of a single individual were monitored for 5 years by wearable devices. This retrospective and exploratory analysis revealed significant changes in blood oxygen saturation, pulse rate, respiration rate, and perfusion index in response to Qi Gong practice and physiological adaptation to its long-term training. Among the physiological changes in vital signs, a physiological state with a significant 2-fold increase in pulse-respiration rate ratio was detected during Qi Gong meditation while the ratios were maintained at 4 under resting, sleeping, and mild cycling conditions. This is an inaugural report of a five-year longitudinal observation of this kind. Once validated in a well-designed cohort study, these non-invasive and easily obtained vital signs may be used as biomarkers to assess the adherence to breathing control during Qi Gong practice and can be applied to quantify the quality of Qi Gong practice in clinical trials with Qi Gong intervention.

Abstract 5979: Evaluating therapeutic strategies against lung cancer using multispectral optoacoustic tomography

Abstract Tumor hypoxia is an important feature of the microenvironment in various types of tumors. The leaky and compressed vessels in the tumor lead to impaired blood flow and oxygen delivery and cause hypoxia. Significant tumor hypoxia exists in non-small cell lung cancer (NSCLC) and is closely associated with radiation-resistant and poor survival. Recently, we have identified a new class of antitumor drugs, cyclopamine tartrate (CycT) and heme-sequestering peptide 2 (HeSP2). They are heme-targeting agents that effectively inhibit NSCLC oxidative metabolism, oxygen consumption, and ATP generation, which lead to the suppression of tumor progression. By using multispectral optoacoustic tomography (MSOT), an advanced noninvasive imaging modality that monitors the changes in blood oxygen saturation and vascular function in real-time, we observed the effect of heme-targeting agents in normalizing tumor vasculature and alleviating tumor hypoxia. To investigate the impact of heme-targeting agent on mediating the lung cancer radiotherapy response, we characterized the vasculature and antigenic profile of NSCLC growth during the treatment of CycT in combination with radiotherapy by performing MSOT, together with other imaging approaches including bioluminescence imaging (BLI) and immunohistochemistry (IHC). We demonstrated that the heme-targeting agents increased tumor radiation sensitivity by regulating tumor vasculature and oxygenation. Our novel combination therapy can be a powerful strategy in improving the treatment of lung cancer and potentially other radiation-resistant cancers. Citation Format: Tianyuan Wang, Hashini Wanniarachchi, Lorena Arango, Li Zhang, Li Liu. Evaluating therapeutic strategies against lung cancer using multispectral optoacoustic tomography [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5979.

Changes and significance of retinal blood oxygen saturation and oxidative stress indexes in patients with diabetic retinopathy.

BACKGROUNDDiabetic retinopathy (DR) is a diabetic complication that can severely affect the patients’ vision, eventually leading to blindness. DR is the most important manifestation of diabetic micro-vasculopathy and is mainly related to the course of diabetes and the degree of blood glucose control, while the age of diabetes onset, sex, and type of diabetes have little influence on it. AIMTo explore the changes in blood oxygen saturation and oxidative stress indices of retinal vessels in patients with DR.METHODSIn total, 94 patients (94 eyes) with DR (DR group) diagnosed at Jianyang people’s Hospital between March 2019 and June 2020, and 100 volunteers (100 eyes) (control group) without eye diseases, were included in this study. Arterial and venous blood oxygen saturation, retinal arteriovenous vessel diameter, and serum oxidative stress indicators in the two groups were compared. Based on the stage of the disease, the DR group was divided into the simple DR and proliferative DR groups for stratified analysis. RESULTSThe oxygen saturation of the retinal vessels in the DR group was significantly higher than that in the control group (P < 0.05). The retinal vessel diameters between the DR and control groups were not significantly different. The serum malondialdehyde (MDA) and 8-hydroxydehydroguanosine (8-OHdG) levels in the DR group were significantly higher than those in the control group (P < 0.05). The serum superoxide dismutase (SOD) and reduced glutathione (GSH) levels in the DR group were significantly lower than those in the control group (P < 0.05). The oxygen saturation of the retinal vessels in the patients with proliferative DR was significantly higher than that in the patients with simple DR (P < 0.05). The retinal vessel diameter in patients with proliferative DR was not significantly different from that of patients with simple DR (P > 0.05). Serum MDA and 8-OHdG levels in patients with proliferative DR were significantly higher than those in patients with simple DR (P < 0.05). Serum SOD and GSH levels in patients with proliferative DR were significantly lower than those in patients with simple DR (P < 0.05).CONCLUSIONIncreased blood oxygen saturation of retinal arteries and veins and increased oxidative stress damage in patients with DR may be associated with decreased retinal capillary permeability and arterial oxygen dispersion, possibly reflecting the patient’s condition.

Effect of transfusion convalescent recovery plasma in patients with coronavirus disease 2019.

To evaluate curative effects of coronavirus disease 2019 (COVID-19) patients by the transfusion of other convalescent plasma. Retrospective analysis of the clinical data of 18 patients with severe and critical COVID-19, who were hospitalized in the ICU of Xianghu Branch of the First Affiliated Hospital of Nanchang University from February 1 to March 15, 2020. Patients were subdivided into an experimental group (n=6, who had transfused the plasma) and an observation group (n=12, who had no plasma transfusion). Basic clinical data and prognosis indexes of these two groups were compared. Moreover, for the experimental group, the dynamic changes of blood oxygen saturation before and after the transfusion, the changes of lymphocyte absolute value 48 hours after the transfusion, and the detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid were analyzed. There were no significant differences in age, gender, blood type and other basic clinical data between the two groups (all P>0.05).There were no significant differences in ventilator machine weaning time, extracorporeal membrane oxygenation (ECMO) weaning time, body temperature recovery to normal time, and hospitalization days between these two groups (all P>0.05). For the experimental group, before, during and after the convalescent plasma transfusion, the blood oxygen saturation of all 6 patients at all time (1, 6, 8, 12, 24, 36, and 48 h) was more than 90%, and there was no significant fluctuation. There were 3 patients whose absolute value of lymphocyte was increased 48 hours after the transfusion, and the remaining was decreased. There were 5 patients whose SARS-CoV-2 nucleic acid detection turned negative 48 hours after the transfusion, accounting for 83.3%. Transfusion of convalescent plasma will not affect outcomesof COVID-19 patients, which can neutralize SARS-CoV-2 in patients and reduce the loading capacity of SARS-CoV-2.

Multi-spectral laser speckle contrast images using a wavelength-swept laser.

.A multi-spectral laser speckle contrast imaging (MS-LSCI) system is proposed using only a single wavelength-swept laser, which provides both highly coherent and multi-spectral outputs to simultaneously generate laser speckle contrast images and multi-spectral images, respectively. Using a laser light swept from 770 to 821 nm at a repetition rate of 5 Hz and a CCD camera of 335 fps, 67 multi-spectral frame images are acquired in 0.76 nm wavebands over 51 nm spectral range. The spectral sub-windowing method of single wavelength-swept laser source is used to solve the lack of spectral information from a few individual light sources, which is a limitation of conventional MS-LSCI systems. In addition to the speckle flow index from the LSCI frames, the multi-spectrally encoded images can generate additional images of spectral absorbance. To further examine the performance of the MS-LSCI system, an in vivo cuff-induced ischemia experiment was conducted to show the real-time imaging of hemodynamic and blood oxygen saturation changes simultaneously over the entire field of view.

The study about the change of the blood oxygen saturation and pulse rate of the nursing staff under abrupt highland advancing.

Objective To evaluate the changes in blood oxygen saturation and pulse rate of the nurses under abrupt highland advancing and provide the fundamentals for those nurses under abrupt highland advancing to Tibet. Methods We selected 12 nursing staffs abruptly advanced to Lhasa at an altitude of 3 650 meters for Abrupt Advancing Group then chose 12 nursing staffs over there for Highland Group from November 2017 to December 2017. To assess whether there is a difference about the change of blood oxygen saturation and pulse rate between these two groups, we measured them in 24 nurses and 360 shifts before work and at 0.5, 1.0, 3.0, 6.0 h after work. Then, we compared the changes in blood oxygen saturation and pulse rate between different ages, sexes, shifts. Results No significant difference in blood oxygen saturation was observed between the two groups before starting work (P > 0.05). Blood oxygen saturation of Abrupt Advancing Group (0.5, 1.0, 3.0, 6.0 h) after work was respectively 0.91±0.01, 0.91±0.02, 0.91±0.02, 0.91±0.01. Meanwhile, the parameters of Highland Group was separately 0.94±0.02, 0.93±0.01, 0.94±0.01, 0.94±0.01. There was a significant difference between the two groups (t=5.153-8.151, P 0.05). A positive difference between the sexes could be found about the changes in the blood oxygen saturation of Abruptly Advancing Group at 0.5, 1.0, 3.0 and 6.0 h after work. What′s more, there was a significant difference in pulse rates before and after work (t=3.283-6.719, P < 0.05 or 0.01). Conclusions The nursing staff in the Abruptly Advancing Group shows decreased blood oxygen saturation and increased pulse rate compared to those in the Highland Group during working period. In addition, the changes show more significant in those working at night, but they adapted gradually. Gender and working time have a significant effect on the change in blood oxygen saturation and increased pulse rate of the nursing staff. Key words: Nurses; Abruptly highland advancing; Oxygen saturation

Hydrogen and Oxygen Mixture to Improve Cardiac Dysfunction and Myocardial Pathological Changes Induced by Intermittent Hypoxia in Rats.

Obstructive sleep apnea (OSA) can cause intermittent changes in blood oxygen saturation, resulting in the generation of many reactive oxygen species (ROS). To discover new antioxidants and clarify the endoplasmic reticulum (ER) stress involved in cardiac injury in OSA, we established a chronic intermittent hypoxia (CIH) rat model with a fraction of inspired O2 (FiO2) ranging from 21% to 9%, 20 times/h for 8 h/day, and the rats were treated with H2-O2 mixture (67% hydrogen and 33% oxygen) for 2 h/day for 35 days. Our results showed that H2-O2 mixture remarkably improved cardiac dysfunction and myocardial fibrosis. We found that H2-O2 mixture inhalation declined ER stress-induced apoptosis via three major response pathways: PERK-eIF2α-ATF4, IRE 1-XBP1, and ATF 6. Furthermore, we revealed that H2-O2 mixture blocked c-Jun N-terminal kinase- (JNK-) MAPK activation, increased the ratio of Bcl-2/Bax, and inhibited caspase 3 cleavage to protect against CIH-induced cardiac apoptosis. In addition, H2-O2 mixture considerably decreased ROS levels via upregulating superoxide dismutase (SOD) and glutathione (GSH) as well as downregulating NADPH oxidase (NOX 2) expression in the hearts of CIH rats. All the results demonstrated that H2-O2 mixture significantly reduced ER stress and apoptosis and that H2 might be an efficient antioxidant against the oxidative stress injury induced by CIH.

Noninvasive Anatomical and Functional Imaging of Orthotopic Glioblastoma Development and Therapy using Multispectral Optoacoustic Tomography

PURPOSE: Here we demonstrate the potential of multispectral optoacoustic tomography (MSOT), a new non-invasive structural and functional imaging modality, to track the growth and changes in blood oxygen saturation (sO2) in orthotopic glioblastoma (GBMs) and the surrounding brain tissues upon administration of a vascular disruptive agent (VDA). METHODS: Nude mice injected with U87MG tumor cells were longitudinally monitored for the development of orthotopic GBMs up to 15 days and observed for changes in sO2 upon administration of combretastatin A4 phosphate (CA4P, 30 mg/kg), an FDA approved VDA for treating solid tumors. We employed a newly-developed non-negative constrained approach for combined MSOT image reconstruction and unmixing in order to quantitatively map sO2 in whole mouse brains. RESULTS: Upon longitudinal monitoring, tumors could be detected in mouse brains using single-wavelength data as early as 6 days post tumor cell inoculation. Fifteen days post-inoculation, tumors had higher sO2 of 63 ± 11% (n = 5, P < .05) against 48 ± 7% in the corresponding contralateral brain, indicating their hyperoxic status. In a different set of animals, 42 days post-inoculation, tumors had lower sO2 of 42 ± 5% against 49 ± 4% (n = 3, P < .05) in the contralateral side, indicating their hypoxic status. Upon CA4P administration, sO2 in 15 days post-inoculation tumors dropped from 61 ± 9% to 36 ± 1% (n = 4, P < .01) within one hour, then reverted to pre CA4P treatment values (63 ± 6%) and remained constant until the last observation time point of 6 hours. CONCLUSION: With the help of advanced post processing algorithms, MSOT was capable of monitoring the tumor growth and assessing hemodynamic changes upon administration of VDAs in orthotopic GBMs.

Behavioral management using sequenced treatment paradigm and audiovisual distraction during dental treatment in children with attention deficit/hyperactivity disorder.

Objective:The present study aimed to assess behavioral management using sequenced treatment approach and audiovisual distraction (AVD) with/without video eyewear during dental procedure in children with attention deficit/hyperactivity disorder (ADHD).Materials and Methods:This clinical trial included 31 children (n = 21 boys; n = 10 girls), aged between 6.5 and 8.1 years, distributed into Group A (n = 17, children not on ADHD medication) and Group B (n = 14, children taking medication for ADHD symptoms). The study involved four sessions, 1 week apart. Sessions I and II included behavioral management assessment and dental screening, respectively, while participants watched cartoon movie using an AV distracter with/without a video eyewear. During Sessions III and IV, dental prophylaxis and sealants were placed on first permanent molars, respectively, for both upper and lower jaws in both the groups. During the procedure, children were distracted with AV distracter with/without a video eyewear, and the mean changes in blood oxygen saturation (SaO2) and pulse rate were recorded every 5 min. Independent samples t-test was used, assessing for significant changes in pulse rate and SaO2 during each visit in both groups.Results:Almost 95% (n = 113) of the first permanent molars showed signs of pit and fissure demineralization of varying severities, classified as the International Caries Detection and Assessment System-codes 1–3. During Session IV, there were significant differences (P ≤ 0.03 and P ≤ 0.05) in mean pulse rate in both groups of children, respectively, during fissure sealants or preventive resin restoration application on their permanent molars while being distracted using AVD with video eyewear.Conclusion:Our study recommends splitting of dental visits into multiple short sessions and video eyewear distraction for optimum behavioral management during dental procedures of children with ADHD.

Application and nursing care of fiberoptic bronchoscopy in mechanical ventilation of patients with acute respiratory distress syndrome

Objective To investigate the application and nursing of fiberoptic bronchoscopy in mechanical ventilation of patients with acute respiratory distress syndrome. Methods 63 patients with acute respiratory distress syndrome who were treated with mechanical ventilation were randomly divided into control group (n=32) and observation group (n=31). The patients in each group were treated with mechanical ventilation and western medicine.The control group was given routine nursing and suctioning.The observation group was treated with fiberoptic bronchoscopy and high quality nursing.The treatment period was 7 days.The changes of blood oxygen saturation (SpO2), arterial blood carbon dioxide partial pressure (PaCO2) and oxygenation index (PaO2/FiO2), the time of mechanical ventilation, the number of cases of ventilator-associated pneumonia (VAP), the number of successful cases of weaning, and the 28-day mortality were observed.The curative effect of the two groups was observed. Results Before treatment, the SpO2, PaCO2, PaO2/FiO2 between the two groups had no statistically significant differences(all P>0.05). After treatment, the SpO2 of the two groups increased [(94.7±3.4)% in the observation group, (90.5±3.0)% in the control group], and the PaCO2 reduced[the observation group (46.1±3.9)mmHg, the control group (52.2±3.4)mmHg], PaO2/FiO2 increased[observation group (222.9±13.6)mmHg, control group (182.2±16.7)mmHg], which of the observation group were better than the control group(t=5.203, 6.624, 10.587, all P<0.01). The time of mechanical ventilation, the number of VAP cases, the number of successful cases of weaning, 28-day mortality in the observation group were (10.2±2.9)d, 2 cases, 24 cases and 22.58%, which were better than those in the control group, the differences were statistically significant (t=6.325, χ2=4.057, 5.10, 4.089, all P<0.05). The total effective rate in the observation group was 77.42%, which was significantly higher than 53.13% in the control group (χ2=4.089, P<0.05). Conclusion Application of fiber bronchoscopy and quality care in the mechanical ventilation of patients with acute respiratory distress syndrome has good effect, it is worthy of clinical promotion. Key words: Bronchoscopy; Respiratory distress syndrome, adult; Ventilation, mechanical; Nursing care

The Dewey monitor: Pulse oximetry can independently detect hypoxia in a rebreather diver.

Rebreather diving has one of the highest fatality rates per man hour of any diving activity in the world. The leading cause of death is hypoxia, typically from equipment or procedural failures. Hypoxia causes very few symptoms prior to causing loss of consciousness. Additionally, since the electronics responsible for controlling oxygen levels in rebreathers often control their alarm systems, frequently divers do not receive any external warnings. This study investigated the use of a forehead pulse oximeter as an independent warning device in the event of rebreather failure. Ten test subjects (seven male, three female, median age 29, range 26-35) exercised at a targeted rate of 2 L/minute oxygen consumption while on a non-functional rebreather breathing loop (mean consumption achieved 2.09 ± 0.36 L/minute). Each subject was tested both at the surface and at pressurized depth of 77 fsw (starting pO₂=0.7 atm). The data show that a pulse oximeter could be used to provide an Mk 16 rebreather diver with a minimum mean of 49 seconds (± 17 seconds SD) of warning time after a noticeable change in blood oxygen saturation (SpO₂ ≤ 95%) but before any risk of loss of consciousness (calculated SpO₂ ≤ 80%), so that the diver may take mitigating actions. No statistical difference in warning time was found between the tests at surface and at 77 fsw (P=0.46).