Blood Oxygen Level Research Articles

Abstract 4143256: Non-invasive, Radiation-free, Non-contrast Myocardial Volume Oxygen Consumption Quantification Using Free-breathing MR Blood Oximetry

Background: Myocardial oxygen consumption (MVO 2 ) is a central marker in measuring cardiac energetics. Current methods to quantify MVO 2 are inaccessible due to the requirement of invasive procedures or PET agents that require onsite cyclotrons. Hypothesis A free-breathing, non-ECG-gated, motion-resolved Cardiac MR blood oximetry technique can noninvasively quantify MVO 2 in standard clinical MRI scanners without using ionizing radiation and contrast agents. Method: The developed free-breathing CMR imaging technique was prescribed in a 3T clinical scanner to the mid left ventricle (LV) and the cross-section of the coronary sinus(CS) slices of the heart to obtain the corresponding blood oxygenation (SbO 2 ) and the hematocrit (Hct) in heart chambers. 2D phase contrast CMR was performed in the CS to quantify the myocardial blood flow (MBF). The MVO 2 was quantified with Fick’s law (MVO 2 =arterio-venous oxygen difference x MBF). We examined the developed method in healthy pigs (N=7) under rest and adenosine stress and validated it against invasive blood sampling. In addition, we tested the method’s clinical feasibility in healthy human volunteers (N=4). Results: Comparable blood oxygenation levels (SbO 2 ) and MVO 2 were measured and compared between the non-invasive CMR and invasive ground truth (Fig. 1). Significantly increased coronary sinus SbO 2 is observed in both methods during adenosine infusion. It is accompanied by decreased MVO 2 and rate pressure product (RPP) (Rest: CMR=10.2±2.7ml/min, Inv.=10.8±6.9 ml/min, RPP=7956.9±620.9 mmHg/min; Stress: CMR=5.3±1.9 ml/min, Inv=6.3±3.6 ml/min, RPP=5338.2±618.3 mmHg/min). In Fig. 2, the healthy human volunteers' MVO 2 estimations(14.1±6.7ml/min) shows no statistical difference compared to the previous invasive measurements(16.5±4.8 ml/min, Ganz, et al. circulation 1971). Conclusions: The proposed noninvasive CMR technique can quantify MVO 2 in standard MRI scanners without using a needle. It has the potential to provide an accessible, risk-free assessment of myocardial metabolism for patients with potential metabolism impairments.

NIMG-26. GLIOBLASTOMA TISSUE INVASION MAPPING WITH NOVEL HYPOXIA-TARGETED BLOOD OXYGENATION-LEVEL DEPENDENT MRI

Abstract BACKGROUND Glioblastoma is a devastating incurable malignant primary brain tumor exhibiting an erratic growth pattern and brain tissue invasion exceeding the typically depicted contrast-enhancing lesion on MRI. This behaviour is strongly associated with the presence of aberrant vasculature. Advanced clinical neuroimaging techniques, however, have not provided convincing imaging markers to determine glioblastoma tissue infiltration and monitor treatment effects. We investigated a new imaging technique based on blood oxygenation-level dependent (BOLD) MRI contrast with precise hypoxic respiratory targeting in order to better determine tumor tissue invasion not restricted to the typically depicted focal glioblastoma lesion on contrast-enhanced MRI. METHODS A computer-controlled gas blender was used to induce transient and standardized hypoxic stimulus in isocapnic conditions during echo-planar-imaging acquisition in patients with brain tumors.8,9 Data were preprocessed using SPM and in-house written MATLAB scripts. The induced BOLD signal changes were used to calculate %BOLD signal change during hypoxic stimulus with respect to the baseline, contrast to noise (CNR) ratio and goodness-of-fit (Rsquared) for each voxel in the whole-brain and automatically segmented region of interest (contrast-enhancement, necrosis, edema) and overlayed using color-maps onto anatomical high resolution T1. RESULTS Hypoxic targeting during gas modulation could be performed with high reproducibility, caused no discomfort in patients with brain tumors and was able to induce strong signal change during hypoxic stimulus with high contrast-noise ratio and Rsquared. In particular, when compared with other tumors, BOLD hypoxia glioblastoma tissue invasion maps show very distinct hypoxic signal responses in some cases extending beyond the focal -contrast-enhancing- glioblastoma lesion. CONCLUSION The ability to map at voxel level BOLD hypoxia signal patterns may determine a novel therapeutic imaging marker based on structural vascular alterations in the tumour tissue infiltration zone before these become appreciable with standard neuroimaging. This may support a refinement and tailoring of tumor resection and improve follow-up after resection and during treatment i.e. chemoradiotherapy.

Advances in Brain-Computer Interface Technology for Depression Diagnosis: A Focus on EEG, MEG, and fNIRS

Abstract. With the acceleration of the pace of modern social life, the psychological pressure on individuals has also increased. Consequently, a series of problems brought about by depression are increasingly recognized, such as its impact on mental health, social functioning, and overall quality of life, and the demand for accurate depression diagnosis has gradually increased. This has led to the exploration of innovative Brain-Computer Interface (BCI)-based diagnostic methods that leverage brain-machine interface technology. The application of related technologies for depression diagnosis is introduced from the aspects of Electroencephalography (EEG), Magnetoencephalography (MEG), and Near-infrared (NIR) imaging technology. These three technologies represent emerging approaches in depression diagnosis, adopting concepts that differ from traditional diagnostic methods. During the diagnostic process, they rely on electrocardiac and brain magnetic field patterns to provide important information related to brain activity. These methods enable non-invasive monitoring of cerebral blood oxygen levels, which is crucial for understanding the physiological underpinnings of depressive symptoms.

Predicting analog intrusions from neural correlates of immediate and lasting effects of cognitive reappraisal.

Emotional dysregulation is considered as an etiologically relevant factor for posttraumatic stress disorder. The relevance of immediate and lasting effects of cognitive reappraisal, a prominent emotion regulation strategy, and its habitual use for the development of posttraumatic stress symptoms in response to an experimental trauma are therefore investigated in our study. Eighty-five healthy women participated in a functional magnetic resonance imaging study, which included an emotion regulation paradigm prior to the conduction of the trauma film paradigm, which was used to assess the development of analog intrusions. During the first phase of the emotion regulation paradigm, participants were instructed to use two reappraisal tactics (reinterpretation and distancing) to reduce negative feelings toward aversive pictures or to passively watch aversive and neutral pictures. One week later, these pictures were presented again during a passive reexposure phase. Ratings of negative feelings and blood oxygen level dependent responses in regions of interest served as main outcome variables. The habitual use of cognitive reappraisal was assessed by questionnaire. Reduced habitual use and stronger lasting effects of cognitive reappraisal, as indicated by reduced insula activation during reexposure to pictures previously reinterpreted and distanced from, predicted the development of long-term analog intrusions. Stronger lasting effects of both reappraisal tactics for women with long-term analog intrusions seem to result from stronger emotional reactivity processes. Women with long-term analog intrusions in response to an experimental trauma seem to benefit to a greater extent from a cognitive reappraisal training than women without long-term intrusions. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Efficacy of Cytoreg in the treatment of diabetic foot disease.

Complications from diabetic foot wounds, including bacterial infection, ulceration and gangrene, are major causes of hospitalisation and are responsible for 85% of amputations in patients with diabetes. Given that orally administered investigational therapeutic Cytoreg (Cytorex de Venezuela SA, Venezuela), a defined aqueous mixture of hydrofluoric, hydrochloric, sulfuric, phosphoric, citric and oxalic acids, has been shown to increase levels of arterial blood oxygen in a Wistar rat model, oral and oral+topical Cytoreg were tested on patients with diabetic foot ulcers (DFUs) under a humanitarian, compassionate-use protocol. All patients received oral Cytoreg (5.0 ml concentrate in fruit juice) for 30 days; half also received weekly wound washing with Cytoreg concentrate in isotonic saline (1:50 volume/volume) (oral+topical group). In addition to standard clinical observations, wounds were monitored against the Saint Elian checklist system for the diabetic foot. A total of 10 patients took part in the study. Complete wound closure was observed in 4/5 patients in the oral+topical group; in the remaining patient, necrotic and fibrin tissues on the wound edges were eliminated. Half (2/4) of the patients receiving oral-only Cytoreg experienced complete wound closure; one patient in this group was removed prematurely because of an unrelated illness and was not replaced. During the study, no significant differences were observed between groups in either the oxygen saturation of the affected tissues or in insulin and glycaemia levels (p<0.05). Significant increases in arterial haemoglobin and arterial oxygen partial pressure (p<0.05) were observed, and significant decreases were measured in the levels of glycosylated haemoglobin, aspartate aminotransferase, glutamic-pyruvic transaminase, creatine and urea (p<0.05). The results of this study justify an expanded clinical study for the treatment of DFUs with Cytoreg.

Prefrontal cortex engagement during an fMRI task of emotion regulation as a potential predictor of treatment response in borderline personality disorder.

Borderline personality disorder (BPD) is a severe mental illness, with high rates of co-morbid depression and suicidality. Despite the importance of optimizing treatment in BPD, little is known about how neural processes relate to individual treatment response. This study examines how baseline regional brain blood oxygen level dependent (BOLD) activation during a functional magnetic resonance imaging (fMRI) task of emotion regulation is related to treatment response following a six-month randomized clinical trial of Dialectical Behavior Therapy (DBT) or Selective Serotonin Reuptake Inhibitor (SSRI) treatment. Unmedicated females with BPD (N = 37), with recent suicidal behavior or self-injury, underwent an fMRI task in which negative personal memories were presented and they were asked to distance (i.e., downregulate their emotional response) or immerse (i.e., experience emotions freely). Patients were then randomized to DBT (N = 16) or SSRI (N = 21) treatment, with baseline and post-treatment depression and BPD severity assessed. BOLD activity in prefrontal cortex, anterior cingulate, and insula was associated with distancing. Baseline BOLD during distancing in dorsolateral, ventrolateral, and orbital prefrontal cortex (dlPFC, vlPFC, OFC) differentially predicted depression response across treatment groups, with higher activity predicting better response in the SSRI group, and lower activity predicting better response in the DBT group. All female samples. Findings indicate that greater prefrontal engagement during emotion regulation may predict more antidepressant benefit from SSRIs, whereas lower engagement may predict better response to DBT. These results suggest different mechanisms of action for SSRI and DBT treatment, and this may allow fMRI to guide individualized treatment selection.

A comparative analysis of the sensitivity and BOLD contamination of the VASO response at 3 Tesla: ME-DEPICTING vs. ME-EPI readouts

Abstract ‘Non-BOLD fMRI’ data acquired at non-zero echo time (TE) suffer from contamination by the Blood Oxygenation Level Dependent (BOLD) signal due to the unavoidable signal decay caused by transverse relaxation. This contamination further reduces their already low inherent functional sensitivities and makes their correction essential. The Slice-Saturation Slab-Inversion Vascular Space Occupancy (SS-SI–VASO), for instance, cancels out BOLD contributions from VASO data, reflecting cerebral blood volume (CBV) changes, via a dynamic division approach. Alternatively, multi-echo (ME) data provide the possibility of extrapolating to TE=0. Acquisitions at very short TE would minimize the need for such corrections. The center-out EPI variant (‘DEPICTING’) is one such readout which allows for short TE. The ME 2D DEPICTING was compared here against a traditional ME 2D EPI for its sensitivity to functional changes in the VASO signal. The two BOLD-correction schemes were also evaluated. Clear differences in functional sensitivity were observed for the uncorrected VASO data obtained from the first echo, TE1, of the two readouts. VASO data corrected by ME extrapolation were, however, found to be almost identical in their sensitivity for detecting CBV changes for both readouts. An excessively high increase in VASO signal sensitivity observed with the dynamic division correction for both readouts revealed a near-perfect linear dependence on TE of VASO signal changes. This could be attributed to the substantial intravascular BOLD contributions at 3 T. In the present data, extravascular ΔR2* fraction was found to be around ~50–60%. ME extrapolation is, hence, recommended to avoid overestimation of functional CBV changes at commonly used TEs.

Pharmacological manipulation of neurotransmitter activity induces disparate effects on cerebral blood flow and resting-state fluctuations

Abstract Functional MRI methods can assess aspects of drug-induced brain response. Resting blood oxygenation level dependent (BOLD) fMRI and arterial spin labeling (ASL) perfusion MRI indirectly measure brain function through the coupling of activity to cerebral blood flow (CBF) and oxygenation but their relative sensitivity has not been directly compared. We assessed changes in resting measures of BOLD and ASL MRI in response to two neurotransmitter modulators: citalopram, a selective serotonin reuptake inhibitor, and alprazolam, a positive allosteric modulator of GABA type A receptor. Thirty healthy subjects were imaged in a placebo-controlled study, with N=20 subjects receiving each treatment as part of an incomplete block design. Time-averaged CBF images from ASL and measures of resting-state fluctuations of BOLD and ASL images were assessed for significant effects. Following acute citalopram administration, analysis of the ASL data showed a reduction in time-averaged regional CBF in regions associated with high levels of 5-HT1A receptor density. In contrast, following alprazolam administration, BOLD amplitude of low frequency fluctuations showed a highly significant and cortically widespread increase, consistent with the distribution of GABA-A receptors. Only a marginal decrease in ASL CBF was detected after alprazolam intake. BOLD and ASL are each sensitive to drugs targeting neurotransmitter systems, but appear to reflect different aspects of neural metabolism and the balance between excitatory and inhibitory activity. Accordingly, their combination may best capture the effects of neurotransmitter modulations, and thus be advantageous for pharmacological MRI studies.

Racial and ethnic and sex differences in at-home estimates of sleep-disordered breathing parameters among Mexican American, Black, and Non-Hispanic White adults.

Background Racial and ethnic and sex differences in sleep may exist, but there are limited data directly comparing objective estimates of sleep-disordered breathing (SDB), particularly in rapid eye movement (REM) versus non-rapid eye movement (NREM) sleep, among Black, Mexican American (MA) and non-Hispanic White (NHW) men and women. Our goal is to investigate health disparities in SDB in a new, diverse cohort of older adults. Research Question Do SDB parameters during REM and NREM sleep differ by race and ethnicity or sex in community-dwelling older adults?. Methods The Dormir Study conducted a comprehensive sleep examination among eligible participants enrolled in the ongoing community-based Health and Aging Brain Study-Health Disparities (HABS-HD) cohort (2020-4), among Black, MA, and NHW adults aged 50 years and older. Here we characterize racial and ethnic and sex differences in SDB indices assessed by an FDA-approved Peripheral Arterial Tonometry (PAT)-based home sleep testing system. Results We examined 821 participants, including 543 (66.1%) women, and 284 (34.6%) MA and 174 (21.2%) Black individuals, with a mean age of 66.6±8.5 years. Around half (50.5%) of the participants had moderate to severe SDB as defined by the respiratory event index (REI based on 3% desaturations) of ≥15/ hour, 72.7% with moderate to severe REM SDB (REM-REI ≥ 15/hour) and 39.5% with moderate to severe NREM SDB (NREM-REI ≥15/hour). The prevalence of SDB did not differ by race or sex. However, significant racial and ethnic and sex differences were observed for REM-specific SDB metrics. Overall, Black women had the highest REM REI, and NHW men had the lowest REM REI and REM ODI. After controlling for age, sex, education, income, employment status, cognitive status, BMI, history of hypertension, diabetes, stroke, and coronary heart disease, and sleep medication use, Black participants had a REM-REI that was 3 events per hour higher than that of NHW adults, while NREM-REI were similar. MA individuals had similar REM or NREM SDB parameters compared to NHW adults but exhibited higher average blood oxygen levels. Conclusions In this community-based cohort of middle- to older-aged NHW, MA, and Black adults, PAT-based measures of in-home sleep indicate a higher prevalence of REM SDB in Black adults, particularly Black women, compared to their NHW counterparts; this contrasts with the similar NREM parameters observed across racial and ethnic groups. Given the close link between REM SDB and adverse health outcomes, clinicians should pay more attention to this sleep apnea phenotype, especially in minoritized populations.

Childhood neglect is associated with alterations in neural prediction error signaling and the response to novelty.

One in eight children experience early life stress (ELS), which increases risk for psychopathology. ELS, particularly neglect, has been associated with reduced responsivity to reward. However, little work has investigated the computational specifics of this disrupted reward response - particularly with respect to the neural response to Reward Prediction Errors (RPE) - a critical signal for successful instrumental learning - and the extent to which they are augmented to novel stimuli. The goal of the current study was to investigate the associations of abuse and neglect, and neural representation of RPE to novel and non-novel stimuli. One hundred and seventy-eight participants (aged 10-18, M = 14.9, s.d. = 2.38) engaged in the Novelty task while undergoing functional magnetic resonance imaging. In this task, participants learn to choose novel or non-novel stimuli to win monetary rewards varying from $0 to $0.30 per trial. Levels of abuse and neglect were measured using the Childhood Trauma Questionnaire. Adolescents exposed to high levels of neglect showed reduced RPE-modulated blood oxygenation level dependent response within medial and lateral frontal cortices particularly when exploring novel stimuli (p < 0.05, corrected for multiple comparisons) relative to adolescents exposed to lower levels of neglect. These data expand on previous work by indicating that neglect, but not abuse, is associated with impairments in neural RPE representation within medial and lateral frontal cortices. However, there was no association between neglect and behavioral impairments on the Novelty task, suggesting that these neural differences do not necessarily translate into behavioral differences within the context of the Novelty task.

Exploring the influence of music on cognitive performance in female assembly line workers at a medical device manufacturing unit.

The significance of enhancing working conditions for the physical health and performance of workers, particularly female workers, underscores the need for research in this domain and the examination of interventions such as music. Previous studies have yielded diverse outcomes regarding the influence of music on individuals' performance; hence, further research in this area appears imperative. The aim of this study is to explore the impact of music on the cognitive and task performance of female assembly operation operators. This study is an interventional (quasi-experimental) study that involved 81 participants from the female workforce of the medical equipment assembly unit in Isfahan, Iran. The evaluation encompassed task performance, working memory using N-Back test, sustained attention using continues performance test (CPT), degree of sleepiness, and mental fatigue using Flicker Fusion test, along with physiological parameters such as heart rate and blood oxygen level. Participants underwent testing both in the presence of classical music and in a condition without music playback. The provision of background music enhanced the workers' sustained attention and working memory. It led to improved task performance and a reduction in drowsiness. Concerning physiological parameters, it resulted in a slight decrease in heart rate at the end of the work shift and a marginal increase in participants' blood oxygen levels. Background music enhanced working memory (p-value = 0.001), sustained attention (p-value = 0.001), and improved the task performance of workers(p-value = 0.005). Additionally, likely due to increased relaxation, it led to a decrease in heart rate (p-value = 0.001) and an increase in blood oxygen levels (p-value = 0.016). Music also played a role in reducing participants' sleepiness (p-value = 0.001).

An IoT Healthcare System With Deep Learning Functionality for Patient Monitoring

ABSTRACTCurrently, healthcare systems operate under conventional management practices and entail storing and processing substantial medical data. Integrating the Internet of Things (IoT) and wireless sensor networks (WSNs) technologies has facilitated the development of IoT‐enabled healthcare, which possesses advanced data processing capabilities and extensive data storage. This paper proposes a WSN and IoT framework for patient monitoring in high‐speed 5G communications. Based on an artificial neural network (ANN), an intelligent health monitoring system was developed using IoT technology to monitor a person's blood pressure, heart rate, oxygen level, and temperature. Furthermore, the system helps the elderly being in critical cases in their homes to communicate and update their medical condition with the hospital, especially in critical cases, to be treated as soon as possible, especially in remote areas. The experimental results showed the superiority and effectiveness of the proposed system. Moreover, relying on ANNs to extract the basic features, the accuracy reached 96%. The proposed system was implemented practically, and the results were displayed in real time and compared with commercial medical devices. Maximum relative errors are heart rate (2.19), body temperature (2.94), systolic blood pressure (3.4), diastolic blood pressure (2.89), and SpO2 (1.05). On the other hand, the proposed system is much faster than other wireless communication methods, regardless of the detection quality.

Neuroimaging Findings for the Overnight Consolidation of Learned Non-native Speech Sounds

Abstract Research over the past two decades has documented the importance of sleep to language learning. Sleep has been suggested to play a role in establishing new speech representations as well; however, the neural mechanisms corresponding to sleep-mediated effects on speech perception behavior are unknown. In this study, we trained monolingual English-speaking adults to perceive differences between the Hindi dental vs. retroflex speech contrast in the evening. We examined the blood oxygen level dependent signal using functional magnetic resonance imaging during perceptual tasks on both the trained talker and on an untrained talker shortly after training, and again the next morning. We also employed diffusion tensor imaging to determine if individual differences in white matter structure could predict variability in overnight consolidation. We found greater activity in cortical regions associated with language processing (e.g., left insula) on the second day. Fractional anisotropy values in the anterior thalamic radiation and the uncinate fasciculus was associated with the magnitude of overnight change in perceptual behavior on the generalization (untrained) talker, after controlling for differences in sleep duration and initial learning. Our findings suggest that speech-perceptual information is subject to an overnight transfer of information to the cortex. Moreover, neural structure appears to be linked to individual differences in efficiency of overnight consolidation.

Photobiomodulation therapy on puncture-associated pain: A controlled randomized double-blind clinical trial.

Dental fear and phobia are prevalent worldwide, with local anesthesia being the most feared procedure. This study aimed to determine whether photobiomodulation therapy (PBMT), used as a pre-anesthetic, could modulate puncture pain and enhance the effectiveness of local anesthesia. In this controlled, randomized, double-blind study, 49 participants were divided into an experimental group (n = 24), which received infrared laser therapy (100 mW, at 808 nm, 8 J, 80 s at a single point) immediately before standard anesthesia; and control group (n = 25), which received the standard anesthetic technique and sham laser. Pain levels were measured using the visual analog scale, and anesthetic efficacy was assessed through electrical tests (latency), percentage of failures, and cartridge usage. Anxiety levels were evaluated using the Beck Anxiety Inventory. Cardiovascular parameters were evaluated through blood pressure, oxygen levels, and heart rate. This randomized, double-blind study found no difference between groups in these experimental conditions. The bias toward a positive PBMT result was sufficiently removed. Autonomic responses of the PBMT group were maintained stable during the procedure.

Highfield imaging of the subgenual anterior cingulate cortex in uni- and bipolar depression.

The subgenual Anterior Cingulate Cortex (sgACC), as a part of the Anterior Cingulate Cortex and the limbic system plays a crucial role in mood regulation. Previous structural and functional brain imaging studies of the sgACC have revealed alterations of Gray Matter (GM) volumes and Blood Oxygenation Level Dependent signals (BOLD) in patients with Major Depressive Disorder (MDD) and Bipolar Disorder (BD), suggesting potential biomarker traits for affective disorders. In this study we investigated the gray matter volume of the sgACC in 3 different patient groups: 40 MDD patients, of which 20 were medicated (MDDm) and 20 were unmedicated (MDDu), and 21 medicated BD patients, and compared them with 23 healthy volunteers. We examined GM volume alteration using high-resolution 7T Magnetic Resonance Imaging (MRI) which produced quantitative maps of the spin-lattice relaxation time (T1). T1 maps provide high contrast between gray and white matter, and at 7 Tesla voxels with submillimeter resolution can be acquired in a reasonable scan time. We developed a semi-automatic segmentation protocol based on refined landmarks derived from previous volumetric studies using quantitative T1 maps as raw input data for automatic tissue segmentation of GM, WM and CSF (cerebrospinal fluid) tissue. The sgACC ROI was then superimposed on these tissue probability maps and traced manually by two independent raters (F.B., M.M.) following our semi-automatic segmentation protocol. Interrater reliability was calculated on a subset of 10 brain scans for each hemisphere, showing an Intra-Class Correlation coefficient (ICC) r = 0.96 for left sgACC and r = 0.84 for right sgACC respectively. In summary, we have developed a reproducible and reliable semi-automatic segmentation protocol to measure gray matter volume in the sgACC. Based on previous findings from meta-analyses on morphometric studies of the sgACC, we hypothesized that patients with MDD would have lower gray matter sgACC volumes compared to healthy subjects. Post-hoc analysis revealed smaller subgenual volumes for the left hemisphere in both the medicated (MDDm) and non-medicated (MDDu) group versus healthy controls (p = .001, p = .008) respectively. For the right hemisphere, the (MDDu) and BD group exhibited significantly lower subgenual volumes than healthy controls (p < .001, p = .004) respectively. To our knowledge, this is the first morphometric MRI study using T1 maps obtained in high-resolution 7 Tesla MRI to compare MDD and BD patients with healthy controls.

A Survey on Data-Driven Approaches for Reliability, Robustness, and Energy Efficiency in Wireless Body Area Networks

Wireless Body Area Networks (WBANs) are pivotal in health care and wearable technologies, enabling seamless communication between miniature sensors and devices on or within the human body. These biosensors capture critical physiological parameters, ranging from body temperature and blood oxygen levels to real-time electrocardiogram readings. However, WBANs face significant challenges during and after deployment, including energy conservation, security, reliability, and failure vulnerability. Sensor nodes, which are often battery-operated, expend considerable energy during sensing and transmission due to inherent spatiotemporal patterns in biomedical data streams. This paper provides a comprehensive survey of data-driven approaches that address these challenges, focusing on device placement and routing, sampling rate calibration, and the application of machine learning (ML) and statistical learning techniques to enhance network performance. Additionally, we validate three existing models (statistical, ML, and coding-based models) using two real datasets, namely the MIMIC clinical database and biomarkers collected from six subjects with a prototype biosensing device developed by our team. Our findings offer insights into strategies for optimizing energy efficiency while ensuring security and reliability in WBANs. We conclude by outlining future directions to leverage approaches to meet the evolving demands of healthcare applications.

Cardiovascular and vasomotor pulsations in the brain and periphery during awake and NREM sleep in a multimodal fMRI study.

The cerebrospinal fluid dynamics in the human brain are driven by physiological pulsations, including cardiovascular pulses and very low-frequency (< 0.1 Hz) vasomotor waves. Ultrafast functional magnetic resonance imaging (fMRI) facilitates the simultaneous measurement of these signals from venous and arterial compartments independently with both classical venous blood oxygenation level dependent (BOLD) and faster arterial spin-phase contrast. In this study, we compared the interaction of these two pulsations in awake and sleep using fMRI and peripheral fingertip photoplethysmography in both arterial and venous signals in 10 healthy subjects (5 female). Sleep increased the power of brain cardiovascular pulsations, decreased peripheral pulsation, and desynchronized them. However, vasomotor waves increase power and synchronicity in both brain and peripheral signals during sleep. Peculiarly, lag between brain and peripheral vasomotor signals reversed in sleep within the default mode network. Finally, sleep synchronized cerebral arterial vasomotor waves with venous BOLD waves within distinct parasagittal brain tissue. These changes in power and pulsation synchrony may reflect systemic sleep-related changes in vascular control between the periphery and brain vasculature, while the increased synchrony of arterial and venous compartments may reflect increased convection of regional neurofluids in parasagittal areas in sleep.

The Effect of the Severity of Chronic Obstructive Pulmonary Disease on the Pituitary Gonadal Axis

This study aims to investigate the levels of anabolic hormone implicated in specific clinical symptoms of chronic obstructive pulmonary disease (COPD) in relation to disease severity. Sixty-four male patients with COPD for at least two years were included. COPD diagnosed was based on pulmonary function tests, with severity classified using the CAT score and mMRC breathlessness scale. Levels of various hormones including TSH T3 T4, FSH, LH, testesterone, prolactin, progesterone and CRP were measured. Arterial blood gases were also analyzed. Patients were categorized according to GOLD stages. LH, FSH levels decreased during exacerbation, with a significant positive correlation between LH and low arterial oxygen levels. lower testosterone levels were statistically significant in severe COPD patients with FEV1 &lt; 50%. A decrease in LH, testosterone FSH, TSH, progesterone and prolactin was observed with low blood oxygen levels, indicating dysfunction in the hypothalamic-pituitary-gonadal axis. However,stastistical significance varied.In conclusion, hormonal changes occur in male COPD patients, particulary related to disease severity. Testesterone levels correlate significantly with COPD severity. LH decrease during pronounced hypoxemia period was notable. Further research is necessary to evaluate the safety and efficacy of testosterone supplementation in COPD patients.

A TECHNIQUE TO SECURE DATA TRANSMISSION IN WIRELESS BODY AREA NETWORKS

The wireless body area networks have contributed to the changes in healthcare sector by enabling continuous monitoring of biomedical parameters remotely on the patient body and offering real time data transmission. Upon collection of the vital signs, they are transmitted to the gateway node which then forwards them to the remote hospital medical servers. Here, these physiological data items are analyzed and necessary action is taken. Such physiological data include electrocardiograms (ECGs), blood pressure, body temperature, blood oxygen levels, respiratory rate, Electroencephalogram (EEG), Electromyogram (EMG), glucose levels, physical activity and Electrodermal Activity (EDA). In this paper, we develop a technique for securely transmitting this sensitive data from the body sensor unit (BSU) to the remote hospital medical server (HMS). KEYWORDS: Sensors, BSU, WBAN, security, privacy

Comprehensive Investigation of Demographic, Clinical, and Paraclinical Findings in Hospitalized Children with COVID-19

Background: Given the differing characteristics of COVID-19 in children compared to adults, there is a need for comprehensive investigations of associated factors in hospitalized children. Objectives: Therefore, we aimed to assess demographic, clinical, and paraclinical findings in hospitalized children with COVID-19. Methods: This study divided hospitalized patients aged three months to 18 years with a positive polymerase chain reaction (PCR) test into two groups: Severe and mild cases. Risk factors, including age, sex, weight, place of residence, clinical symptoms, lung involvement in chest X-rays, and laboratory parameters, were compared between these two groups (mild and severe). Results: The study included 375 hospitalized patients (75 severe and 300 mild cases). The mean age was 7.50 ± 5.57 months. Among the patients, 215 males (58%) were enrolled. Severe cases exhibited a higher frequency of sleepiness (40%) and shortness of breath (41.3%). Clinical signs such as respiratory rate (35 breaths/min) and heart rate (120 bpm) were higher in severe cases, while blood oxygen levels (92%) were lower. Severe cases also showed higher lung involvement in radiographs (85.7%). Among laboratory factors, white blood cell count (8650), neutrophils (6762), and lymphocytes (2090) were higher in severe cases, while alkaline phosphatase (320.5) was lower. Conclusions: Our results highlighted key findings regarding demographic, clinical, and paraclinical features in hospitalized children with COVID-19, offering valuable insights into this novel phenomenon. The study recommends close monitoring of patients with symptoms such as shortness of breath and sleepiness to prevent disease progression to a severe state.