ABSTRACT
This review systematically explores the application of transformer-based models in EEG signal processing and brain-computer interface (BCI) development, with a distinct focus on ensuring methodological rigour and adhering to empirical validations within the existing literature. By examining various transformer architectures, such as the Temporal Spatial Transformer Network (TSTN) and EEG Conformer, this review delineates their capabilities in mitigating challenges intrinsic to EEG data, such as noise and artifacts, and their subsequent implications on decoding and classification accuracies across disparate mental tasks. The analytical scope extends to a meticulous examination of attention mechanisms within transformer models, delineating their role in illuminating critical temporal and spatial EEG features and facilitating interpretability in model decision-making processes. The discourse additionally encapsulates emerging works that substantiate the efficacy of transformer models in noise reduction of EEG signals and diversifying applications beyond the conventional motor imagery paradigm. Furthermore, this review elucidates evident gaps and propounds exploratory avenues in the applications of pre-trained transformers in EEG analysis and the potential expansion into real-time and multi-task BCI applications. Collectively, this review distils extant knowledge, navigates through the empirical findings, and puts forward a structured synthesis, thereby serving as a conduit for informed future research endeavours in transformer-enhanced, EEG-based BCI systems.
Subject(s)
Brain-Computer Interfaces , Electroencephalography , Signal Processing, Computer-Assisted , Humans , Electroencephalography/methods , Brain/physiologyABSTRACT
Objective: This article describes a case of polymicrobial Arcanobacterium haemolyticum pharyngitis and sinusitis complicated by intracranial complications and reviews similar cases in the literature. Case summary: A 21-year-old immunocompetent male presented with symptoms of sore throat, rhinorrhoea, lethargy, headache, and rash. Imaging demonstrated sinusitis, pre-septal sinusitis, peritonsillar abscess formation, subdural empyema and cerebritis. He was managed with endoscopic sinus surgery, craniotomy for evacuation of subdural empyema and antibiotics. Microbiological samples demonstrated growth of A. haemolyticum, strep. anginosus, and fusobacterium necrophorum. He subsequently developed a cerebral abscess requiring stereotactic needle drainage. After a prolonged course of antibiotics, the patient was discharge and made a good recovery. Discussion: A. haemolyticum is an uncommon cause of non-streptococcal pharyngitis that may occur alongside other microorganisms and is rarely associated with severe intracranial complications. This organism and its antibiotic susceptibility patterns should be considered in complicated upper respiratory tract infections in immunocompetent hosts. Penicillins and macrolide antibiotics form the mainstay of therapy for A. haemolyticum.
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BACKGROUND: Jugular foramen dural arteriovenous fistulas (DAVFs) are rare and challenging lesions. Described methods of treatment include embolization and microsurgical disconnection through a far lateral transcondylar approach. The authors present the case of a Borden type III jugular foramen DAVF, which was treated with a novel, less invasive retrosigmoid approach with intradural skeletonization and packing of the sigmoid sinus. OBSERVATIONS: The patient presented with headache and visual field deficit. Neuroimaging demonstrated a right temporal intracerebral hematoma with mass effect. This was due to a Borden type III jugular foramen DAVF with cortical venous reflux into the vein of Labbe secondary to recanalization of a previously thrombosed sigmoid sinus. Microsurgical disconnection was performed via a retrosigmoid approach, in which the sigmoid sinus was identified intradurally at the jugular foramen. The sigmoid sinus was isolated by drilling at the pre- and retrosigmoid spaces to permit packing and clip ligation. Postoperative angiography revealed complete occlusion of the DAVF. LESSONS: Jugular foramen DAVFs are rare entities, which have been traditionally treated through a far lateral transcondylar approach. An intradural retrosigmoid approach is a safe, less invasive alternative, which involves less soft tissue and bony dissection and does not have the associated morbidity of craniocervical instability and hypoglossal neuropathy.
ABSTRACT
The Brain Computer Interface (BCI) is the communication between the human brain and the computer. Electroencephalogram (EEG) is one of the biomedical signals which can be obtained by attaching electrodes to the scalp. Some EEG related applications can be developed to help disabled people, such as EEG based wheelchair or robotic arm. A hybrid BCI real-time control system is proposed to control a multi-tasks BCI robot. In this system, a sliding window based online data segmentation strategy is proposed to segment training data, which enable the system to learn the dynamic features when the subject's brain state transfer from a rest state to a task execution state. The features help the system achieve real-time control and ensure the continuity of executing actions. In addition, Common Spatial Pattern (CSP) can better extract the spatial features of these continuous actions from the dynamic data to ensure that multiple control commands are accurately classified. In the experiment, three subjects' EEG data is collected, trained and tested the performance and reliability of the proposed control system. The system records the robot's spending time, moving distance, and the number of objects pushing down. Experimental results are given to show the feasibility of the real-time control system. Compared to real-time remote controller, the proposed system can achieve similar performance. Thus, the proposed hybrid BCI real-time control system is able to control the robot in the real-time environment and can be used to develop robot-aided arm training methods based on neurological rehabilitation principles for stroke and brain injury patients.
Subject(s)
Brain-Computer Interfaces , Robotic Surgical Procedures , Robotics , Humans , Reproducibility of Results , Electroencephalography/methodsABSTRACT
Mesenchymal stem cells (MSCs) used for clinical applications require in vitro expansion to achieve therapeutically relevant numbers. However, conventional planar cell expansion approaches using tissue culture vessels are inefficient, costly, and can trigger MSC phenotypic and functional decline. Here we present a one-step dry plasma process to modify the internal surfaces of three-dimensional (3D) printed, high surface area to volume ratio (high-SA:V) porous scaffolds as platforms for stem cell expansion. To address the long-lasting challenge of uniform plasma treatment within the micrometre-sized pores of scaffolds, we developed a packed bed plasma immersion ion implantation (PBPI3) technology by which plasma is ignited inside porous materials for homogeneous surface activation. COMSOL Multiphysics simulations support our experimental data and provide insights into the role of electrical field and pressure distribution in plasma ignition. Spatial surface characterisation inside scaffolds demonstrates the homogeneity of PBPI3 activation. The PBPI3 treatment induces radical-containing chemical structures that enable the covalent attachment of biomolecules via a simple, non-toxic, single-step incubation process. We showed that PBPI3-treated scaffolds biofunctionalised with fibroblast growth factor 2 (FGF2) significantly promoted the expansion of MSCs, preserved cell phenotypic expression, and multipotency, while reducing the usage of costly growth factor supplements. This breakthrough PBPI3 technology can be applied to a wide range of 3D polymeric porous scaffolds, paving the way towards developing new biomimetic interfaces for tissue engineering and regenerative medicine.
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Research has advanced considerably since the first clinical trial of human mesenchymal stem cells (MSCs) in the early 1990s. During this period, our understanding of MSC biology and our ability to expand and manipulate these cells have provided hope for the repair of damaged tissues due to illness or injury. MSCs have conventionally been injected systemically or locally into target tissue; however, inconsistent cell homing and engraftment efficiencies represent a major bottleneck that has led to mixed results in clinical studies. To overcome these issues, MSCs have been pre-conditioned with biomolecules, genetically altered, or surface engineered to enhance their homing and engraftment capabilities. In parallel, a variety of cell-encapsulating materials have been designed to improve cell delivery and post-transplantation survival and function. In this review, we discuss the current strategies that have been employed on cultured MSCs to improve targeted cell delivery and retention for tissue repair. We also discuss the advances in injectable and implantable biomaterial technologies that drive the success of MSC-based therapies in regenerative medicine. Multi-faceted approaches combining cellular modification and cell-instructive material design can pave the way for efficient and robust stem cell transplantation for superior therapeutic outcomes.
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Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Humans , Mesenchymal Stem Cell Transplantation/methods , Biocompatible Materials/metabolism , Regenerative Medicine/methodsABSTRACT
Dual antiplatelet therapy (DAPT) is standard treatment for endoluminal stent insertion, and complete resistance to DAPT is rare. A case of in-stent thrombosis occurring 3 hours after stent-assisted coiling of internal carotid artery aneurysm is presented despite compliance with DAPT. Platelet function tests (PFTs) revealed complete clopidogrel and prasugrel resistance.
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The malfunctioning of the heating, ventilating, and air conditioning (HVAC) system is considered to be one of the main challenges in modern buildings. Due to the complexity of the building management system (BMS) with operational data input from a large number of sensors used in HVAC system, the faults can be very difficult to detect in the early stage. While numerous fault detection and diagnosis (FDD) methods with the use of statistical modeling and machine learning have revealed prominent results in recent years, early detection remains a challenging task since many current approaches are unfeasible for diagnosing some HVAC faults and have accuracy performance issues. In view of this, this study presents a novel hybrid FDD approach by combining random forest (RF) and support vector machine (SVM) classifiers for the application of FDD for the HVAC system. Experimental results demonstrate that our proposed hybrid random forest-support vector machine (HRF-SVM) outperforms other methods with higher prediction accuracy (98%), despite that the fault symptoms were insignificant. Furthermore, the proposed framework can reduce the significant number of sensors required and work well with the small number of faulty training data samples available in real-world applications.
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Air Conditioning , Support Vector Machine , Heating , Machine Learning , Models, StatisticalABSTRACT
Cells can sense mechanical signals through cytoskeleton reorganization. We previously discovered the formation of omni-directional actin protrusions upon compression loading, namely compression-induced actin protrusions (CAPs), in human mesenchymal stem cells (MSCs) in 3D micro-tissues. Here, the regulatory roles of three RhoGTPases (CDC42, Rac1 and RhoA) in the formation of CAPs were investigated. Upon compression loading, extensive formation of CAPs was found, significantly associated with an upregulated mRNA expression of Rac1 only, but not CDC42, nor RhoA. Upon chemical inhibition of these RhoGTPase activity during compression, only Rac1 activity was significantly suppressed, associating with the reduced CAP formation. Silencing the upstream regulators of these RhoGTPase pathways including Rac1 by specific siRNA dramatically disrupted actin cytoskeleton, distorted cell morphology and aborted CAP formation. Silencing cortactin (CTTN), a downstream effector of the Rac1 pathway, induced a compensatory upregulation of Rac1, enabling the MSCs to respond to the compression loading stimulus in terms of CAP formation, although at a reduced number. The importance of Rac1 signalling in CAP formation and the corresponding upregulation of lamellipodial markers also suggest that these CAPs are lamellipodia in nature. This study delineates the mechanism of compression-induced cytoskeleton reorganization, contributing to rationalizing mechanical loading regimes for functional tissue engineering.
Subject(s)
Actins , Mesenchymal Stem Cells , Actins/metabolism , Collagen , Humans , Mesenchymal Stem Cells/metabolism , cdc42 GTP-Binding Protein/metabolism , rac1 GTP-Binding Protein/metabolismABSTRACT
Carotid artery pseudoaneurysm is a rare complication of transsphenoidal surgery, usually diagnosed within 90 days post procedure. Sequelae of pseudoaneurysm rupture, such as severe epistaxis or carotid cavernous fistula (CCF), have significant morbidity and mortality. A case of epistaxis from pseudoaneurysm rupture over a decade after transsphenoidal surgery is presented, with staged treatment using coiling, endonasal mucosal flap repair and interval flow-diverting stent insertion. This case illustrates that pseudoaneurysm rupture occurs regardless of time course after transsphenoidal surgery, and treatment strategies using combined endovascular and endonasal techniques are reviewed.
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Carotid Artery, Internal, Dissection/etiology , Carotid-Cavernous Sinus Fistula/etiology , Epistaxis/etiology , Neurosurgical Procedures/adverse effects , Postoperative Complications/etiology , Humans , Male , Time FactorsABSTRACT
Coronavirus disease 2019 (COVID-19) infection has now reached a pandemic state, affecting more than a million patients worldwide. Predictors of disease outcomes in these patients need to be urgently assessed to decrease morbidity and societal burden. Lactate dehydrogenase (LDH) has been associated with worse outcomes in patients with viral infections. In this pooled analysis of 9 published studies (n = 1532 COVID-19 patients), we evaluated the association between elevated LDH levels measured at earliest time point in hospitalization and disease outcomes in patients with COVID-19. Elevated LDH levels were associated with a ~6-fold increase in odds of developing severe disease and a ~16-fold increase in odds of mortality in patients with COVID-19. Larger studies are needed to confirm these findings.
Subject(s)
Betacoronavirus , Coronavirus Infections/enzymology , L-Lactate Dehydrogenase/blood , Pandemics , Pneumonia, Viral/enzymology , Biomarkers/blood , C-Reactive Protein/metabolism , COVID-19 , Coronavirus Infections/epidemiology , Global Health , Humans , Pneumonia, Viral/epidemiology , SARS-CoV-2 , Severity of Illness Index , Survival Rate/trendsSubject(s)
Coronavirus Infections/mortality , Demography , Pneumonia, Viral/mortality , Betacoronavirus , Brazil , COVID-19 , China , Comorbidity , Female , Humans , Italy , Male , Middle Aged , Pandemics , SARS-CoV-2Subject(s)
Female , Humans , Male , Middle Aged , Pneumonia, Viral/mortality , Demography , Coronavirus Infections/mortality , Brazil , Comorbidity , China , Pandemics , Betacoronavirus , SARS-CoV-2 , COVID-19 , ItalyABSTRACT
Observational studies have reported an association between underlying cardiovascular diseases (CVD) and worse prognosis in COVID-19 patients, but this still remains unclear. We conducted a meta-analysis of recent studies that reported the association of CVD with worse prognosis and increased mortality in COVID-19 patients. Literature search through PubMed, the Cochrane Library, and Embase was completed by 2 reviewers from November 1, 2019 to April 20, 2020. Inclusion criteria were observational case-control or cohort studies on COVID-19 patients with a history of CVD included, which reported outcomes of COVID-19 infection severity, clearly outlined the definition of "severe disease" and with sample size >10. Data were abstracted independently by 2 authors. Studies were divided into 2 separate cohorts for analysis: severity (severe vs nonsevere) and mortality (nonsurvivors vs survivors). Data was pooled into a meta-analysis to estimate pooled odds ratio (OR) with 95% confidence interval (95% CI) for each outcome. A total of 18 studies (nâ¯=â¯4858 patients) were included. Sixteen studies were from China, while 2 were from the United States. Pre-existing CVD was associated with a significantly increased risk of a severe form of COVID-19 (ORâ¯=â¯3.14; 95% CI 2.32-4.24; I2â¯=â¯0%; Qâ¯=â¯8.68, P= 0.73) and overall risk of COVID-19 all-cause mortality (ORâ¯=â¯11.08; 95% CI: 2.59-47.32; I2â¯=â¯55%; Pâ¯=â¯0.11). However, this study did not find a significant association between previous history of CVD and mortality in severe COVID-19 disease (ORâ¯=â¯1.72; 95% CI: 0.97-3.06, I2â¯=â¯0%, Pâ¯=â¯0.46). Pre-existing CVD is associated with worse outcomes among patients with COVID-19. Clinicians and policymakers need to take account of these findings in implementing risk stratification models.
Subject(s)
Cardiovascular Diseases , Coronavirus Infections , Mortality , Pandemics , Pneumonia, Viral , Risk Assessment/methods , Severity of Illness Index , Betacoronavirus/isolation & purification , COVID-19 , Cardiovascular Diseases/diagnosis , Cardiovascular Diseases/epidemiology , Comorbidity , Coronavirus Infections/diagnosis , Coronavirus Infections/epidemiology , Humans , Observational Studies as Topic , Pneumonia, Viral/diagnosis , Pneumonia, Viral/epidemiology , Prognosis , SARS-CoV-2ABSTRACT
BACKGROUND: Up to 30% of thyroid nodules undergoing fine needle aspiration (FNA) yield an indeterminate result. Recent research efforts have suggested that nuclear morphometry and morphology may enhance the diagnostic accuracy of FNA as an objective adjunct. We applied nuclear morphometric analysis on a diverse cohort of patients to evaluate the association between nuclear morphometry and malignancy. METHODS: Forty-five randomly selected patients, who underwent thyroid surgery after an indeterminate FNA result (Bethesda III & IV) between 2012-2015, were reviewed. One hundred representative nuclei per FNA of a thyroid nodule were analyzed using ImageJ. Seven validated morphometric parameters were collected: nuclear area, perimeter, circularity, aspect ratio, roundness, and maximum/minimum Feret's diameter. L/S ratio was subsequently calculated. All 8 nuclear parameters were reported as averages with standard errors of the mean (SEM). A Student's t-test was used to assess the association of nuclear parameters with final surgical pathology. RESULTS: The mean age of all patients was 56.31±15.39 years, with female patients comprising 68.9% of the cohort. Twenty-two patients had malignant thyroid nodules. The mean perimeter of nuclei for the cohort was 18.48±0.45 µm, the mean area was 22.19±0.93 µm, and the mean maximum Feret's diameter was 6.67±0.13 µm. No significant differences in the 8 nuclear parameters were observed between the malignant and non-malignant groups. CONCLUSIONS: In the population examined, our results suggest that nuclear morphometry is not yet a tool of reliable diagnostic value in accessing malignant and non-malignant thyroid nodules. Further investigation is necessary to identify objective parameters that will enhance diagnostic accuracy of indeterminate FNA cytology to minimize the number of diagnostic thyroid surgery.
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INTRODUCTION: As the outbreak of coronavirus disease 2019 (COVID19) was recognized, the clinical predictors of severe or fatal course of the disease should be identified to enable risk stratification and to allocate limited resources optimally. Hypertension has been widely reported to be associated with increased disease severity; however, some studies reported different findings. OBJECTIVES: The study aimed to evaluate the association between hypertension and severe and fatal COVID19. PATIENTS AND METHODS: The Scopus, Medline, and Web of Science databases were searched to identify studies reporting the rate of hypertensive patients in the population diagnosed with severe or nonsevere COVID19 or in COVID-19 survivors and nonsurvivors. The obtained data were pooled into a metaanalysis to calculate odds ratios (ORs) with 95% CIs. RESULTS: Hypertension was associated with a nearly 2.5fold increased risk of severe COVID19 (OR, 2.49; 95% CI, 1.98-3.12; I2 = 24%), as well as with a similarly significant higher mortality risk (OR, 2.42; 95% CI, 1.51-3.90; I2 = 0%). In a metaregression analysis, a correlation was observed between an increase in the mean age of patients with severe COVID19 and an increased log OR of hypertension and COVID-19 severity (P = 0.03). CONCLUSIONS: This pooled analysis of the current literature would suggest that hypertension may be associated with an up to 2.5fold higher risk of severe or fatal COVID19, especially in older individuals.
Subject(s)
Coronavirus Infections , Hypertension , Pandemics , Pneumonia, Viral , Aged , Betacoronavirus , COVID-19 , Coronavirus Infections/complications , Coronavirus Infections/mortality , Humans , Hypertension/complications , Mortality/trends , Pneumonia, Viral/complications , Pneumonia, Viral/mortality , Prognosis , Risk Factors , SARS-CoV-2 , Severity of Illness IndexABSTRACT
The ubiquitous occurrences of microplastics in the environment have raised much concern and resulted in voluminous studies related to microplastics. Studies on microplastics pollution of the marine environment have received significantly higher attention compared to those of the freshwater and terrestrial environments. With the impetus to better understand microplastics in the freshwater and terrestrial environments, this review elucidates the findings of >100 articles related to the prevalence, fates and impacts of microplastics therein and the sustainable solutions, mostly in the past 10 years. This review shows the interconnection between terrestrial and freshwater microplastics with wastewater and sewage treatment plants as the most significant contributors of environmental microplastics via sludge and effluent discharges. Microplastics in both ecosystems comprise the primary and secondary forms with the latter resulted from weathering of the former. Besides retaining in soil and infiltrating with rainwater underground, terrestrial microplastics also enter the freshwater environment. The environmental microplastics interact with the biotic and abiotic components resulting in entrainment, settlement, biofouling, degradation, fragmentation and entry into the food chain, with subsequent transfer across the food chain. The abundance of environmental microplastics is attributed to population density and urbanization though tidal cycle, storms, floods and human activities can affect their distribution. The leaching of additives from microplastics poses major health concern and sustainable solutions target at reduction of plastics use and disposal, substitution with bioplastics and wastewater treatment innovations. Further studies on classification, detection, characterization and toxicity of microplastics are necessary to permit more effective formulation of solutions.
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BACKGROUND: Capillary hemangiomas of the skin and soft tissue are a common entity, while capillary hemangiomas of the central nervous system are an extremely rare pathology. There are less than 20 published cases of intradural lesions involving the cauda equina. CASE PRESENTATION: Herein, we describe a young patient with a capillary hemangioma of the cauda equina that underwent successful surgical resection. CONCLUSION: Natural history and post-operative follow-up for patients with spinal intradural capillary hemangioma are uncertain. This is the sole case to have not recurred at 12 months which underwent gross total resection and had a high proliferative index.
Subject(s)
Cauda Equina/pathology , Hemangioma, Capillary/pathology , Neoplasm Recurrence, Local/pathology , Peripheral Nervous System Neoplasms/pathology , Adult , Diagnosis, Differential , Hemangioma, Capillary/diagnosis , Humans , Magnetic Resonance Imaging , Male , Neoplasm Recurrence, Local/diagnosis , Peripheral Nervous System Neoplasms/diagnosisABSTRACT
BACKGROUND: Symptoms of Temporomandibular Disorders (TMD) could affect oral health-related quality of life (OHRQoL) and psychological distress. OBJECTIVE: This study aims to determine the prevalence of TMD symptoms, and impact of type and number of TMD symptoms on OHRQoL and psychological states among Asian military personnel. METHOD: The study was conducted across 12 military dental centres using self-administered questionnaire comprising demographical data, DC/TMD symptom questionnaire, OHIP-14 and DASS-21. A total of 3028 personnel, aged between 18-65 years old, were invited to participate with an acceptance rate of 90.5%. Data analysis was done using non-parametric tests, regression analysis and Spearman correlation (P < 0.05). RESULTS: Out of 2043 subjects (1998 males; 45 females, mean age 24.18 ± 7.18 years), 36.32% (n = 742) reported at least one TMD symptom. Significant differences in summary OHIP-14, depression, anxiety and stress scores were observed between subjects with and without TMD symptoms. Significant differences in OHIP-14 and DASS-21 scores were observed between dissimilar type and number of TMD symptoms in the TMD group. Those with headaches and 2-3 symptoms have substantially poorer OHRQoL and greater psychological distress. Associations between number of TMD symptoms, quality of life, depression, anxiety and stress were significant but weak (r = 0.19-0.40). CONCLUSIONS: Symptoms of Temporomandibular Disorders were prevalent among Asian military population. Significant differences in OHRQoL and psychological states were observed between subjects with and without TMD symptoms. Specific type and number of TMD symptoms impacted OHRQoL and psychological states differently. Associations between number of TMD symptoms and quality of life, depression, anxiety and stress were significant but weak.