-
ArXiv Mar 2024Deep Brain Stimulation (DBS) stands as an effective intervention for alleviating the motor symptoms of Parkinson's disease (PD). Traditional commercial DBS devices are...
Deep Brain Stimulation (DBS) stands as an effective intervention for alleviating the motor symptoms of Parkinson's disease (PD). Traditional commercial DBS devices are only able to deliver fixed-frequency periodic pulses to the basal ganglia (BG) regions of the brain, i.e., continuous DBS (cDBS). However, they in general suffer from energy inefficiency and side effects, such as speech impairment. Recent research has focused on adaptive DBS (aDBS) to resolve the limitations of cDBS. Specifically, reinforcement learning (RL) based approaches have been developed to adapt the frequencies of the stimuli in order to achieve both energy efficiency and treatment efficacy. However, RL approaches in general require significant amount of training data and computational resources, making it intractable to integrate RL policies into real-time embedded systems as needed in aDBS. In contrast, contextual multi-armed bandits (CMAB) in general lead to better sample efficiency compared to RL. In this study, we propose a CMAB solution for aDBS. Specifically, we define the context as the signals capturing irregular neuronal firing activities in the BG regions (i.e., beta-band power spectral density), while each arm signifies the (discretized) pulse frequency of the stimulation. Moreover, an {\epsilon}-exploring strategy is introduced on top of the classic Thompson sampling method, leading to an algorithm called {\epsilon}-Neural Thompson sampling ({\epsilon}-NeuralTS), such that the learned CMAB policy can better balance exploration and exploitation of the BG environment. The {\epsilon}-NeuralTS algorithm is evaluated using a computation BG model that captures the neuronal activities in PD patients' brains. The results show that our method outperforms both existing cDBS methods and CMAB baselines.
PubMed: 38560737
DOI: No ID Found -
Cureus Jul 2023Cardiovascular disease has become a huge burden to human health. Artificial intelligence (AI)-enabled smartwatches continuously monitor the heart rate, which...
Cardiovascular disease has become a huge burden to human health. Artificial intelligence (AI)-enabled smartwatches continuously monitor the heart rate, which potentially helps to diagnose unwarranted rhythm and irregularity problems such as tachycardia, bradycardia, and fibrillation. Deep learning (DL), convolutional neural networks (CNN), and support vector machines are various modalities of AI adopted in the field of cardiology extensively, starting from a single echocardiogram to cardiac imaging. Yet, the efficacy and safety of machine learning in healthcare have always raised valid questions for the manufacturers of various healthcare devices. It is thus challenging and promising to see how AI in medicine will affect human lives in tackling various medical conditions along with global threats such as pandemics. A case report on idiopathic ventricular tachycardia (VT) detected by an AI-aided smartwatch is presented in this paper.
PubMed: 37602056
DOI: 10.7759/cureus.42054 -
Cancers May 2024This study aimed to predict stress in patients using artificial intelligence (AI) from biological signals and verify the effect of stress on respiratory irregularity. We...
This study aimed to predict stress in patients using artificial intelligence (AI) from biological signals and verify the effect of stress on respiratory irregularity. We measured 123 cases in 41 patients and calculated stress scores with seven stress-related features derived from heart-rate variability. The distribution and trends of stress scores across the treatment period were analyzed. Before-treatment information was used to predict the stress features during treatment. AI models included both non-pretrained (decision tree, random forest, support vector machine, long short-term memory (LSTM), and transformer) and pretrained (ChatGPT) models. Performance was evaluated using 10-fold cross-validation, exact match ratio, accuracy, recall, precision, and F1 score. Respiratory irregularities were calculated in phase and amplitude and analyzed for correlation with stress score. Over 90% of the patients experienced stress during radiation therapy. LSTM and prompt engineering GPT4.0 had the highest accuracy (feature classification, LSTM: 0.703, GPT4.0: 0.659; stress classification, LSTM: 0.846, GPT4.0: 0.769). A 10% increase in stress score was associated with a 0.286 higher phase irregularity ( < 0.025). Our research pioneers the use of AI and biological signals for stress prediction in patients undergoing radiation therapy, potentially identifying those needing psychological support and suggesting methods to improve radiotherapy effectiveness through stress management.
PubMed: 38893087
DOI: 10.3390/cancers16111964 -
Frontiers in Cardiovascular Medicine 2023The rising adoption of wearable technology increases the potential to identify arrhythmias. However, specificity of these notifications is poorly defined and may cause...
Evaluation of atrial fibrillation using wearable device signals and home blood pressure data in the Michigan Predictive Activity & Clinical Trajectories in Health (MIPACT) Study: A Subgroup Analysis (MIPACT-AFib).
BACKGROUND
The rising adoption of wearable technology increases the potential to identify arrhythmias. However, specificity of these notifications is poorly defined and may cause anxiety and unnecessary resource utilization. Herein, we report results of a follow-up screening protocol for incident atrial fibrillation/flutter (AF) within a large observational digital health study.
METHODS
The MIPACT Study enrolled 6,765 adult patients who were provided an Apple Watch and blood pressure (BP) monitors. From March to July 2019, participants were asked to contact the study team for any irregular heart rate (HR) notification. They were assessed using structured questionnaires and asked to provide 6 Apple Watch EKGs. Those with arrhythmias or non-diagnostic EKGs were sent 7-day monitors. The EHR was reviewed after 3 years to determine if participants developed arrhythmias.
RESULTS
86 participants received notifications and met inclusion criteria. Mean age was 50.5 (SD 16.9) years, and 46 (53.3%) were female. Of 76 participants assessed by the study team, 32 (42.1%) reported anxiety surrounding notifications. Of 59 participants who sent at least 1 EKG, 52 (88.1%) were in sinus rhythm, 3 (5.1%) AF, 2 (3.4%) indeterminate, and 2 (3.4%) sinus bradycardia. Cardiac monitor demonstrated AF in 2 of 3 participants with AF on Apple Watch EKGs. 2 contacted their PCPs and were diagnosed with AF. In total, 5 cases of AF were diagnosed with 1 additional case identified during EHR review.
CONCLUSION
Wearable devices produce alarms that can frequently be anxiety provoking. Research is needed to determine the implications of these alarms and appropriate follow-up.
PubMed: 38188255
DOI: 10.3389/fcvm.2023.1243574 -
Polymers Sep 2023Dual-pulsed (DPL) laser deposition using oyster shells as targets was studied in order to find out if this method can replace the use of high-power pulsed lasers....
Dual-pulsed (DPL) laser deposition using oyster shells as targets was studied in order to find out if this method can replace the use of high-power pulsed lasers. Aspects related to changes in the morphological structure of the thin layer but also to the chemical composition of the obtained thin layer were analyzed and compared with the target as well as with the thin layers obtained with a higher power pulsed laser in a single-pulsed (SPL) regime. Orthorhombic structures were noticed with Scanning Electron Microscopy for the thin film obtained in DPL mode compared to the irregular particles obtained in SPL mode. The deacetylation process during ablation was evidenced by Fourier Transform Infrared spectroscopy, resulting in chitosan-based thin films. The effect of the obtained thin films of chitosan on the cells of baker's yeast () was studied. Restoration of the yeast paste into initial yeast was noticed mainly when the hemp fabric was used as support for the coating with yeas which was after that coated with chitosan thin film produced by DPL method.
PubMed: 37836002
DOI: 10.3390/polym15193953 -
Skeletal Radiology May 2024To investigate the feasibility and application of a novel imaging technique, a three-dimensional dual adiabatic inversion recovery prepared ultrashort echo time (3D...
PURPOSE
To investigate the feasibility and application of a novel imaging technique, a three-dimensional dual adiabatic inversion recovery prepared ultrashort echo time (3D DIR-UTE) sequence, for high contrast assessment of cartilaginous endplate (CEP) imaging with head-to-head comparisons between other UTE imaging techniques.
METHOD
The DIR-UTE sequence employs two narrow-band adiabatic full passage (AFP) pulses to suppress signals from long T water (e.g., nucleus pulposus (NP)) and bone marrow fat (BMF) independently, followed by multispoke UTE acquisition to detect signals from the CEP with short T relaxation times. The DIR-UTE sequence, in addition to three other UTE sequences namely, an IR-prepared and fat-saturated UTE (IR-FS-UTE), a T-weighted and fat-saturated UTE sequence (T-FS-UTE), and a fat-saturated UTE (FS-UTE) was used for MR imaging on a 3 T scanner to image six asymptomatic volunteers, six patients with low back pain, as well as a human cadaveric specimen. The contrast-to-noise ratio of the CEP relative to the adjacent structures-specifically the NP and BMF-was then compared from the acquired images across the different UTE sequences.
RESULTS
For asymptomatic volunteers, the DIR-UTE sequence showed significantly higher contrast-to-noise ratio values between the CEP and BMF (CNR) (19.9 ± 3.0) and between the CEP and NP (CNR) (23.1 ± 1.7) compared to IR-FS-UTE (CNR: 17.3 ± 1.2 and CNR: 19.1 ± 1.8), T-FS-UTE (CNR: 9.0 ± 2.7 and CNR: 10.4 ± 3.5), and FS-UTE (CNR: 7.7 ± 2.2 and CNR: 5.8 ± 2.4) for asymptomatic volunteers (all P-values < 0.001). For the spine sample and patients with low back pain, the DIR-UTE technique detected abnormalities such as irregularities and focal defects in the CEP regions.
CONCLUSION
The 3D DIR-UTE sequence is able to provide high-contrast volumetric CEP imaging for human spines on a clinical 3 T scanner.
Topics: Humans; Low Back Pain; Bone and Bones; Magnetic Resonance Imaging; Cartilage; Phantoms, Imaging; Imaging, Three-Dimensional
PubMed: 37935923
DOI: 10.1007/s00256-023-04503-4 -
Journal of Hazardous Materials Mar 2024Poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride (PHMB) is a biocide with a broad spectrum of antibacterial activity. Its use as a disinfectant and...
Assessment of poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride-induced developmental neurotoxicity via oxidative stress mechanism: Integrative approaches with neuronal cells and zebrafish.
Poly(hexamethylenebicyanoguanide-hexamethylenediamine) hydrochloride (PHMB) is a biocide with a broad spectrum of antibacterial activity. Its use as a disinfectant and preservative in consumer products results in human exposure to PHMB. Toxicity studies on PHMB mainly focus on systemic toxicity or skin irritation; however, its effects on developmental neurotoxicity (DNT) and the underlying mechanisms are poorly understood. In this study, the DNT effects of PHMB were evaluated using IMR-32 and SH-SY5Y cell lines and zebrafish. In both cell lines, PHMB concentrations ≥ 10 µM reduced neurite outgrowth, and cytotoxicity was observed at concentrations up to 40 µM. PHMB regulated expression of neurodevelopmental genes and induced reactive oxygen species (ROS) production and mitochondrial dysfunction. Treatment with N-acetylcysteine reversed the toxic effects of PHMB. Toxicity tests on zebrafish embryos showed that PHMB reduced viability and heart rate and caused irregular hatching. PHMB concentrations of 1-4 µM reduced the width of the brain and spinal cord of transgenic zebrafish and attenuated myelination processes. Furthermore, PHMB modulated expression of neurodevelopmental genes in zebrafish and induced ROS accumulation. These results suggested that PHMB exerted DNT effects in vitro and in vivo through a ROS-dependent mechanism, highlighting the risk of PHMB exposure.
Topics: Animals; Humans; Reactive Oxygen Species; Zebrafish; Neuroblastoma; Oxidative Stress; Disinfectants; Embryo, Nonmammalian; Diamines
PubMed: 38064952
DOI: 10.1016/j.jhazmat.2023.133146 -
Pediatric Rheumatology Online Journal Nov 2023It has been reported that the complete heart block (CHB) in neonatal lupus (NL) cannot be reversed. This study reported a case of NL-CHB that was reversed by...
BACKGROUND
It has been reported that the complete heart block (CHB) in neonatal lupus (NL) cannot be reversed. This study reported a case of NL-CHB that was reversed by transcutaneous pacing and repeated plasmapheresis.
CASE PRESENTATION
A 35-week male preterm baby was transferred to the neonatal intensive care unit of the Army Medical Center in May 2020 for slight cyanosis around the lips and nose. Two days after birth, a sudden decrease in heart rate was observed during electrocardiogram (EGG) monitoring. Physical examination revealed a bluish-purple discoloration around the lips and an irregular heartbeat. EGG showed the presence of isolated P (142 bpm) and QRS (78 bpm) waves, ventricular escape beats, and a diagnosis of NL-CHB. To reverse the condition, transcutaneous pacing and five sessions of plasmapheresis were performed. At a 1.5-year follow-up, the baby exhibited well-developed cardiac structure and normal neurodevelopment.
CONCLUSIONS
Transcutaneous pacing and repeated plasmapheresis might be possible to reverse CHB in NL.
Topics: Infant, Newborn; Humans; Male; Heart Block; Electrocardiography; Plasmapheresis
PubMed: 37946215
DOI: 10.1186/s12969-023-00920-w -
PloS One 2023Deep-sea macrobenthic body fossils are scarce due to the lack of deep-sea sedimentary archives in onshore settings. Therefore, hypothesized migrations of shallow shelf...
Deep-sea macrobenthic body fossils are scarce due to the lack of deep-sea sedimentary archives in onshore settings. Therefore, hypothesized migrations of shallow shelf taxa into the deep-sea after phases of mass extinction (onshore-offshore pattern in the literature) due to anoxic events is not constrained by the fossil record. To resolve this conundrum, we investigated 1,475 deep-sea sediment samples from the Atlantic, Pacific and Southern oceans (water depth ranging from 200 to 4,700 m), providing 41,460 spine fragments of the crown group Atelostomata (Holasteroida, Spatangoida). We show that the scarce fossil record of deep-sea echinoids is in fact a methodological artefact because it is limited by the almost exclusive use of onshore fossil archives. Our data advocate for a continuous record of deep-sea Atelostomata back to at least 104 Ma (late early Cretaceous), and literature records suggest even an older age (115 Ma). A gradual increase of different spine tip morphologies from the Albian to the Maastrichtian is observed. A subsequent, abrupt reduction in spine size and the loss of morphological inventory in the lowermost Paleogene is interpreted to be an expression of the "Lilliput Effect", related to nourishment depletion on the sea floor in the course of the Cretaceous-Paleogene (K-Pg) Boundary Event. The recovery from this event lasted at least 5 Ma, and post-K-Pg Boundary Event assemblages progress-without any further morphological breaks-towards the assemblages observed in modern deep-sea environments. Because atelostomate spine morphology is often species-specific, the variations in spine tip morphology trough time would indicate species changes taking place in the deep-sea. This observation is, therefore, interpreted to result from in-situ evolution in the deep-sea and not from onshore-offshore migrations. The calculation of the "atelostomate spine accumulation rate" (ASAR) reveals low values in pre-Campanian times, possibly related to high remineralization rates of organic matter in the water column in the course of the mid-Cretaceous Thermal Maximum and its aftermath. A Maastrichtian cooling pulse marks the irreversible onset of fluctuating but generally higher atelostomate biomass that continues throughout the Cenozoic.
Topics: Fossils; Oceans and Seas; Extinction, Biological; Biomass; Water; Biological Evolution
PubMed: 37556403
DOI: 10.1371/journal.pone.0288046 -
Magnetic Resonance in Medical Sciences... Sep 2023Polarity-corrected inversion time preparation (PCTIP), a myocardial T1 mapping technique, is expected to reduce measurement underestimation in the modified Look-Locker...
Novel T1 Analysis Method to Address Reduced Measurement Accuracy Due to Irregular Heart Rate Variability in Myocardial T1 Mapping Using Polarity-corrected Inversion Time Preparation.
PURPOSE
Polarity-corrected inversion time preparation (PCTIP), a myocardial T1 mapping technique, is expected to reduce measurement underestimation in the modified Look-Locker inversion recover method. However, measurement precision is reduced, especially for heart rate variability. We devised an analysis using a recurrence formula to overcome this problem and showed that it improved the measurement accuracy, especially at high heart rates. Therefore, this study aimed to determine the effect of this analysis on the accuracy and precision of T1 measurements for irregular heart rate variability.
METHODS
A PCTIP scan using a 3T MRI scanner was performed in phantom experiment. We generated the simulated R-waves required for electrocardiogram (ECG)-gated acquisition using a signal generator set to 30 combinations. T1 map was generated using the signal train of the PCTIP images by nonlinear curve fitting using conventional and recurrence formulas. Accuracy against reference T1 and precision of heart rate variability were evaluated. To evaluate the fitting accuracy of both analyses, the relative fitting error was calculated.
RESULTS
For the longer T1, the fitting error was larger than the short T1, with the conventional analysis showing 10.1±2.0%. The recurrence formula analysis showed a small fitting error less than 1%, which was consistent for all heart rate variability patterns. In the conventional analysis, the accuracy, especially for longer T1, showed a large underestimation of the measurements and poor linearity. However, in the recurrence formula analysis, the accuracy improved at a long T1, and linearity also improved. The Bland-Altman plot showed that it varied greatly depending on the heart rate variability pattern for the longer T1 in the conventional analysis, whereas the recurrence formula analysis suppressed this variation.
CONCLUSION
T1 analysis of PCTIP using the recurrence formula analysis achieved accurate and precise T1 measurements, even for irregular heart rate variability.
PubMed: 37661369
DOI: 10.2463/mrms.mp.2023-0029