Data Augmentation Techniques for Accurate Action Classification in Stroke Patients with Hemiparesis.

Stroke survivors with hemiparesis require extensive home-based rehabilitation. Deep learning-based classifiers can detect actions and provide feedback based on patient data; however, this is difficult owing to data sparsity and heterogeneity. In this study, we investigate data augmentation and model training strategies to address this problem. Three transformations are tested with varying data volumes to analyze the changes in the classification performance of individual data. Moreover, the impact of transfer learning relative to a pre-trained one-dimensional convolutional neural network (Conv1D) and training with an advanced InceptionTime model are estimated with data augmentation. In Conv1D, the joint training data of non-disabled (ND) participants and double rotationally augmented data of stroke patients is observed to outperform the baseline in terms of F1-score (60.9% vs. 47.3%). Transfer learning pre-trained with ND data exhibits 60.3% accuracy, whereas joint training with InceptionTime exhibits 67.2% accuracy under the same conditions. Our results indicate that rotational augmentation is more effective for individual data with initially lower performance and subset data with smaller numbers of participants than other techniques, suggesting that joint training on rotationally augmented ND and stroke data enhances classification performance, particularly in cases with sparse data and lower initial performance.

Investigating Activity Recognition for Hemiparetic Stroke Patients Using Wearable Sensors: A Deep Learning Approach with Data Augmentation.

Measuring the daily use of an affected limb after hospital discharge is crucial for hemiparetic stroke rehabilitation. Classifying movements using non-intrusive wearable sensors provides context for arm use and is essential for the development of a home rehabilitation system. However, the movement classification of stroke patients poses unique challenges, including variability and sparsity. To address these challenges, we collected movement data from 15 hemiparetic stroke patients (Stroke group) and 29 non-disabled individuals (ND group). The participants performed two different tasks, the range of motion (14 movements) task and the activities of daily living (56 movements) task, wearing five inertial measurement units in a home setting. We trained a 1D convolutional neural network and evaluated its performance for different training groups: ND-only, Stroke-only, and ND and Stroke jointly. We further compared the model performance with data augmentation from axis rotation and investigated how the performance varied based on the asymmetry of movements. The joint training of ND + Stroke yielded an increased F1-score by a margin of 31.6% and 10.6% compared to ND-only training and Stroke-only training, respectively. Data augmentation further enhanced F1-scores across all conditions by an average of 11.3%. Finally, asymmetric movements decreased the F1-score by 25.9% compared to symmetric movements in the Stroke group, indicating the importance of asymmetry in movement classification.

Minimizing Precision-Weighted Sensory Prediction Errors via Memory Formation and Switching in Motor Adaptation.

Humans predict the sensory consequences of motor commands by learning internal models of the body and of environment perturbations. When facing a sensory prediction error, should we attribute this error to a change in our body, and update the body internal model, or to a change in the environment? In the latter case, should we update an existing perturbation model or create a new model? Here, we propose that a decision-making process compares the models' prediction errors, weighted by their precisions, to select and update either the body model or an existing perturbation model. When no model can predict a perturbation, a new perturbation model is created and selected. When a model is selected, both the prediction's mean estimate and uncertainty are updated to minimize future prediction errors and to increase the precision of the predictions. Results from computer simulations, which we verified in an arm visuomotor adaptation experiment with subjects of both sexes, account for short aftereffects and large savings after adaptation to large, but not small, perturbations. Results also clarify previous data in the absence of errors (error-clamp): motor memories show an initial lack of decay after a large perturbation, but gradual decay after a small perturbation. Finally, qualitative individual differences in adaptation were explained by subjects selecting and updating either the body model or a perturbation model. Our results suggest that motor adaptation belongs to a general class of learning according to which memories are created when no existing memories can predict sensory data accurately and precisely.SIGNIFICANCE STATEMENT When movements are followed by unexpected outcomes, such as following the introduction of a visuomotor or a force field perturbation, or the sudden removal of such perturbations, it is unclear whether the CNS updates existing memories or creates new memories. Here, we propose a novel model of adaptation, and investigate, via computer simulations and behavioral experiments, how the amplitude and schedule of the perturbation, as well as the characteristics of the learner, lead to the selection and update of existing memories or the creation of new memories. Our results provide insights into a number of puzzling and contradictory motor adaptation data, as well as into qualitative individual differences in adaptation.

Mathematical modeling and its analysis for instability of the immune system induced by chemotaxis.

In this paper, we study how chemotaxis affects the immune system by proposing a minimal mathematical model, a reaction-diffusion-advection system, describing a cross-talk between antigens and immune cells via chemokines. We analyze the stability and instability arising in our chemotaxis model and find their conditions for different chemotactic strengths by using energy estimates, spectral analysis, and bootstrap argument. Numerical simulations are also performed to the model, by using the finite volume method in order to deal with the chemotaxis term, and the fractional step methods are used to solve the whole system. From the analytical and numerical results for our model, we explain not only the effective attraction of immune cells toward the site of infection but also hypersensitivity when chemotactic strength is greater than some threshold.

Optimal Schedules in Multitask Motor Learning.

Although scheduling multiple tasks in motor learning to maximize long-term retention of performance is of great practical importance in sports training and motor rehabilitation after brain injury, it is unclear how to do so. We propose here a novel theoretical approach that uses optimal control theory and computational models of motor adaptation to determine schedules that maximize long-term retention predictively. Using Pontryagin's maximum principle, we derived a control law that determines the trial-by-trial task choice that maximizes overall delayed retention for all tasks, as predicted by the state-space model. Simulations of a single session of adaptation with two tasks show that when task interference is high, there exists a threshold in relative task difficulty below which the alternating schedule is optimal. Only for large differences in task difficulties do optimal schedules assign more trials to the harder task. However, over the parameter range tested, alternating schedules yield long-term retention performance that is only slightly inferior to performance given by the true optimal schedules. Our results thus predict that in a large number of learning situations wherein tasks interfere, intermixing tasks with an equal number of trials is an effective strategy in enhancing long-term retention.

Clinical Characteristics of the Suicide Attempters Who Refused to Participate in a Suicide Prevention Case Management Program.

Case management interventions for suicide attempters aimed at helping adjust their social life to prevent reattempts have high nonparticipation and dropout rates. We analyzed the clinical characteristics of the group who refused to participate in the suicide prevention program in Korea. A total of 489 patients with a suicide attempt who visited Uijeongbu St. Mary's Hospital, the Catholic University of Korea, from December 2009 to December 2013 were analyzed. All patients were divided into the participation group (n = 262) and the refusal group (n = 227) according to their participation in the case management program. Demographic and clinical characteristics of each group were examined. Results showed that the refusal group had low risks for suicide in terms of risk factors related with psychopathologies and presenting suicide behavior. That is, the refusal group had less patients with co-morbid medical illnesses and more patients with mild severity of depression compared to the participation group. However, the refusal group had more interpersonal conflict, more isolation of social integrity, and more impaired insight about suicide attempt. The results suggest that nonparticipation in the case management program may depend upon the patient's impaired insight about the riskiness of suicide and lack of social support.

Traumatic lumbar artery rupture after lumbar spinal fracture dislocation causing hypovolemic shock: An endovascular treatment.

Recently, we observed a case of lumbar artery injury after trauma, which was treated by endovascular embolization. A 67-year-old woman who was injured in a traffic accident was brought to the emergency room. She was conscious and her hemodynamic condition was stable, but she had paraplegia below L1 dermatome. Contrast-enhanced computed tomography scan of abdomen and pelvis revealed fracture dislocation of L3/4 along with retroperitoneal hematomas. However, there was no evidence of traumatic injury in both thoracic and abdominal cavity. At that time, her blood pressure suddenly decreased to 60/40 mmHg and her mental status deteriorated. Also, her hemoglobin level was 5.4 g/dl. While her hemodynamic condition stabilized with massive fluid resuscitation including blood transfusion, an angiography was immediately performed to look for and embolize site of retroperitoneal hemorrhage. On the angiographic images, there was an active extravasation from ruptured left 3rd lumbar artery, and we performed complete embolization with GELFOAM and coil. Lumbar artery injury after trauma is rare and endovascular treatment is useful in case of hemodynamic instability.

Eosinophilic pleuritis due to sparganum: a case report.

Sparganosis is a rare parasitic disease caused by migrating plerocercoid tapeworm larva of the genus Spirometra. Infection in humans is mainly caused by the ingestion of raw or inadequately cooked flesh of infected frogs, snakes, and chickens. Here, we report a rare case of a 45-year-old man who was admitted to our hospital with left lower chest pain. The chest radiograph and computed tomography (CT) scan revealed localized pleural effusion in the left lower lobe; further, peripheral blood eosinophilia and eosinophilic pleural effusion were present. Percutaneous catheter drainage was performed, which revealed long worm-shaped material that was identified as a sparganum by DNA sequencing. The patient showed clinical improvement after drainage of the sparganum. This study demonstrates the importance of considering parasitic diseases in the differential diagnosis of eosinophilic pleural effusion.

Proteomic evaluation to identify biomarkers for carpal tunnel syndrome: a comparative serum analysis.

Carpal tunnel syndrome (CTS) is the most common peripheral nerve entrapment, causing pain, impairment, and disability. To identify proteins of CTS comprehensively, a comparative serum analysis of CTS patients and normal control subjects was performed. The two-dimensional electrophoresis patterns of serum obtained from six CTS patients and six normal control subjects were compared. We found 10 proteins that were significantly altered in the serum of CTS patients, among which four were upregulated and six were downregulated. The upregulated spots were identified as Chain A, heat shock 70-kDa protein, 42-kDa ATPase N-terminal domain; glutathione-insulin transhydrogenase (216AA); cAMP-dependent protein kinase inhibitor alpha; and mutant ß-globin. The downregulated spots were identified as vitamin D-binding protein (VDBP), fibrinogen gamma chain, apolipoprotein A-IV (ApoA-IV), clusterin, heterogeneous nuclear ribonucleoprotein H1 (hnRNP H1), and one unidentified protein. The information obtained from this proteomic analysis will be very useful in understanding the pathophysiology of CTS and in finding suitable proteins that can serve as new diagnostic biomarkers of CTS.

Moyamoya syndrome following growth hormone-secreting pituitary adenoma.

We report a case of Moyamoya syndrome developing in association with growth hormone-secreting pituitary adenoma. A 31-year-old female presented with acromegalic features. Magnetic resonance imaging revealed a 1 × 2 cm tumor in the sella turcica and MR angiography demonstrated unremarkable findings. Blood growth hormone and insulin-like growth factor I levels were elevated to 74.1 ng/ml and over 1 575 ng/ml, respectively. The diagnosis was growth hormone-secreting pituitary adenoma, and the tumor was removed through a transsphenoidal approach. Four years after surgery, she visited the outpatient department due to left side weakness for 2 months. Magnetic resonance images showed acute and old infarcted lesions in the basal ganglia and subcortical area and residual small pituitary adenoma in the sellar area. MR angiography demonstrated stenosis of the bilateral distal internal carotid arteries with basal collateral vessels. Conventional cerebral angiography showed complete obstruction in the right internal carotid artery and severe stenosis of the left internal carotid artery, middle cerebral artery, and anterior cerebral artery with basal collateral vessels. Her blood growth hormone and insulin-like growth factor I levels were 15.3 ng/ml and 1 055 ng/ml, respectively. We believe that excess systemic exposures of growth hormone and insulin-like growth factor I may participate in the development of Moyamoya syndrome.

Traumatic lateral atlantoaxial dislocation combined with a type II odontoid fracture in a patient with ankylosing spondylitis: A case report.

RATIONALE: Traumatic lateral atlantoaxial dislocation (AAD) combined with an odontoid fracture is extremely rare. The standards applicable to management of the traumatic lateral AAD are still in flux due to the infrequency of this injury. PATIENT CONCERNS: We present a unique case of traumatic lateral AAD combined with a type II odontoid fracture in a patient with ankylosing spondylitis (AS). DIAGNOSIS: Spinal computed tomography showed ankylosis of the entire spine from the sacroiliac joint to the cervical spine. On the cervical X-ray the head was rotated to the right with anterior subluxation of the C1 and odontoid tip relative to C2. The coronal computed tomography (CT) scan also revealed left lateral dislocation of C1 on C2 with a horizontal translation of the odontoid tip. On the axial and sagittal CT scan, the left C1 lateral mass was displaced anteriorly and locked by C2 body. INTERVENTIONS: We performed occipito-cervical fusion (OCF) after successful manual reduction under general anesthesia. OUTCOMES: The patient's recovery from surgery was uneventful and without complication. At the 3 year follow-up the patient was asymptomatic and reportedly satisfied with the surgery. LESSONS: Traumatic AAD with an odontoid fracture is an exceedingly uncommon cervical spine injury. A lateral subluxation with a type II odontoid fracture in a patient with AS is rarer still, so much so that this type of subluxation was not classifiable using any of the previously developed classification systems. In this patient with AS, posterior OCF with internal fixation was necessary to avoid hardware failure, particularly in light of the intensive stress caused by AS.

Fabrication of conductive silver paste recovered from leaching of waste catalyst using hydrochloric acid.

Transition metal compounds based on silver (Ag) and palladium (Pd) are extensively used as catalysts in the petrochemical industries. The catalytic activities of Ag and Pd decrease over time and hence need to be discarded. The recovery of elements like Ag from waste catalyst is essential because of its limited availability and cost, and it is environmentally beneficial with regards to recycling. In this study, Pd and Ag were leached from waste catalyst providing an alternative source suitable for a Ag paste electrode. Through an efficient reduction process, AgCl particles were obtained which serve as a precursor to synthesize Ag using ammonia as the solvent. The obtained Ag was fabricated to Ag paste by using mixed dispersion and solvent. The electrical resistivity of the Ag paste was recorded as 6.14 µΩ cm at 417 °C in a hydrogen atmosphere.

Elderly suicide attempters by self-poisoning in Korea.

BACKGROUND: Suicide is a major public health concern. The elderly have the highest rate of suicide and they make more lethal suicide attempts and have fewer psychiatric interventions than young people. Furthermore, they have old-age specific psychosocial difficulties. The present study investigated psychosocial risk factors and characteristics of an index suicide attempt of the elderly suicide attempters. METHODS: Subjects included 388 patients who were admitted to the emergency room following self-poisoning. Two age groups were defined: younger patients (aged less than 65 years) and older patients (aged over 65 years). Data including demographic factors, suicidal risk factors and information about the current suicide attempt were obtained from a retrospective chart review. RESULTS: The number of suicide attempters over the age of 65 years old was 57, and their mean age was 73.5 ± 7.5 years. The elderly patients had more underlying medical illnesses than the under-65 group (p < 0.001). Depression was the most common psychiatric diagnosis. Psychotropics were the most commonly ingested drugs in both groups, but the use of pesticides was more notable in the elderly. The elderly suicide attempters had higher risk-rating scores (p < 0.001) and lower rescue-rating scores (p = 0.014) than the under-65 group. Male-to-female ratio of the elderly group was nearly 1:1 unlike the under-65 group (p = 0.004). CONCLUSION: Elderly suicide attempters had different psychosocial stressors such as physical illness and more lethal suicide attempts. Our study suggests the need for development of specific preventive strategies and management guidelines for the elderly suicide attempters.

The relationship between radiologic parameters and transverse atlantal ligament injury obtained from MRI scans in patients with an isolated atlas burst fracture: A retrospective observational study.

ABSTRACT: The treatment of an atlas burst fracture depends on whether transverse atlantal ligament (TAL) injury is present. We compared the radiologic parameters associated with the presence of a TAL injury as detected using magnetic resonance imaging (MRI), and verified whether the lateral mass displacement (LMD) criteria currently used to diagnose TAL injuries in atlas burst fractures are reliable or need revision.Thirty patients who presented with isolated atlas burst fractures were included in this retrospective observational study. We measured radiologic parameters, including LMD, atlanto-dental interval, basion-dens interval, internal lateral mass displacement, and external lateral mass displacement, in each patient at the time of initial presentation. The presence of TAL injury was evaluated using MRI. We compared the radiologic parameters and characteristics of patients who presented with TAL injury. We also determined the sensitivity and specificity of an LMD test to accurately diagnose TAL injury based on MRI. Finally, we compared the radiologic parameters according to the presence of surgical treatment and patient union status.Twenty patients presented with an intact TAL, while 10 patients had a TAL injury on MRI. LMD was significantly higher in patients with TAL injury (9.61 vs 3.73 mm, P < .001). In multivariable logistic regression analysis, LMD was also significantly higher in patients with TAL injury. The sensitivity and specificity of LMD for diagnosing TAL injury based on MRI in patients with isolated C1 fractures were 90% and 100%, respectively. The incidence of an LMD greater than 8.1 mm was statistically higher in patients than in those without TAL injury (90% vs 0%, P < .001).Nine patients underwent surgery for isolated atlas burst fractures, and 21 did not. LMD (9.56 vs 4.03 mm, P < .001) and fracture gap (7.96 vs 4.01 mm, P < .001) were significantly higher in patients who underwent surgery.Among the various radiologic parameters, LMD closely correlated with the presence of TAL injury, as patients with an LMD greater than 8.1 mm were more likely to have a TAL injury in the case of atlas burst fractures. LMD is a good method for predicting the presence of TAL injury if MRI is not available.

Posterior epidural migration of lumbar disc fragment: Case reports and literature review.

INTRODUCTION: Posterior epidural migration of lumbar disc fragment (PEMLDF) is a very rare condition that may lead to a serious neurological deficit such as cauda equina syndrome. Magnetic resonance imaging (MRI) findings can often result in cases of PEMLDF being misdiagnosed as extradural masses of other origin or epidural hematomas. In this study, we reported four additional cases of PEMLDF and reviewed the relevant literature. PATIENT CONCERNS: We present four patients with PEMLDF. The mean age of the patients was 53.5 years. Two patients suffered from cauda equine syndrome, and the other two patients complained of radiculopathy. DIAGNOSIS: The MRI findings in each case showed masses with slightly high signal intensity in T2-weighted images, as well as heterogenous and peripheral rim enhancement after contrast enhancement. In some patients there was a tract-like enhancement extending from the outer aspect of the disc to the posterolateral epidural space. A definitive diagnosis was made intraoperatively. INTERVENTIONS: We performed laminectomy and discectomy in all patients. OUTCOMES: The PEMLDF patients with radiculopathy had no complaints of weakness or pain after surgery. Both patients with cauda equine syndrome showed a total recovery post-surgery. CONCLUSIONS: Early diagnosis and treatment via laminectomy and discectomy is critical to achieving the best postoperative outcomes. Understanding the patient's history, recognizing the similar signal intensity of the mass and intervertebral disc on MRI scans, and looking for peripheral rim enhancement, are the keys to the correct diagnosis of PEMLDF.

Symptomatic perineural cyst after spontaneous subarachnoid hemorrhage: A case report.

RATIONALE: Tarlov or perineurial cysts are nerve root lesions often found in the sacral region. Most perineural cysts (PCs) remain asymptomatic throughout a patient's life. While their pathogenesis is still unclear, trauma resulting in hemorrhaging into subarachnoid space has been put forward as a possible cause of these cysts. Recently, we worked with a patient experiencing symptomatic PCs after spontaneous subarachnoid hemorrhage. PATIENT CONCERNS: A 45-year-old man had a coil embolization procedure performed after being diagnosed with a subarachnoid hemorrhage from a ruptured anterior communicating artery. His symptoms were relieved after the procedure, but 7 days later he reported worsening pain in the left perineal area. The pain was intermittent at its onset and exacerbated by sitting, walking, and coughing. DIAGNOSES: Two weeks after the embolization procedure, a lumbar spine MRI revealed 2 PCs at the S1 and S2 level affecting the left S2 root with high signal intensity in T2 and T1 images, suggestive of bleeding within the cyst. INTERVENTIONS: We operated using a posterior approach. Cyst fenestration was done after S1 laminectomy. We aspirated approximately 1 cc of old blood. OUTCOMES: His pain was relieved immediately after cyst removal and no neurologic deterioration occurred during the postoperative period. LESSONS: Subarachnoid hemorrhage can be the source of the development of pain from asymptomatic PCs, making them symptomatic. Surgical extirpation is 1 treatment option for these symptomatic PCs.

Endotracheal intubation using a GlideScope video laryngoscope by emergency physicians: a multicentre analysis of 345 attempts in adult patients.

OBJECTIVE: To investigate the use and success rates of the GlideScope (GVL) by emergency physicians (EPs) during the initial two years after its introduction. METHODS: We performed an observational study using registry data of five emergency departments. The success rates in adult patients were evaluated and compared with those of conventional laryngoscope (CL). RESULTS: The GVL was used in 345 (10.7%) of 3233 intubation attempts by EPs. The overall success rate of the GVL was not higher than a CL (79.1% vs 77.6%, p=0.538). The success rate for the patients with difficult airway was higher in the GVL than a CL (80.0% vs 50.4%, p<0.001). CONCLUSION: The GVL was not used frequently by EPs during the initial two years after its introduction. Although the GVL provides a better glottic view, the overall success rates were similar to a CL. The GVL may be useful in patients with difficult airway.

Nurse-Led Computerized Cognitive Training for Mild Cognitive Impairment: A Preliminary Study.

PURPOSE: This preliminary study aimed to compare the outcomes of an occupational therapist-led and a nurse-led computerized cognitive training (CCT) for mild cognitive impairment (MCI) in older adults. DESIGN: A single-blind randomized controlled trial was performed. METHODS: Participants 65 years of age and older with MCI were randomly assigned to a group led by an occupational therapist or by a nurse. Both groups received CCT for 4 weeks. FINDINGS: Six participants in the occupational therapist-led group and nine in the nurse-led group completed CCT. The nurse-led group showed significant improvement in scores on the Seoul Verbal Learning Test-Elderly's version immediate recall scores (p = .030) and the Korean-Boston Naming Test (p = .012). CONCLUSIONS: Nurse-led CCT demonstrated improvement in some language and memory areas in older adults with MCI. CLINICAL RELEVANCE: This study supports the idea of educating nurses to use a CCT program for treating older adults with MCI to improve their cognitive function.

A case report of aneurysmal bone cyst of the thoracic spine treated by serial anterior and posterior fusion.

RATIONALE: Aneurysmal bone cyst (ABC) is a benign, reactive, non-neoplastic, proliferative, highly vascular osseous lesion. Because of the rarity of aggressive ABC cases, diagnostic and treatment protocols remain controversial and problematic. Treatment of ABC includes surgery, radiotherapy, selective arterial embolization (SAE), and a combination of these modalities. Successful outcomes have been reported, but the technical requirements and complications of each modality are quite different. We report the clinical, radiological, and therapeutic aspects of ABC of the thoracic spine in an adolescent who was treated by circumferential fusion, and we review the published literature. PATIENT CONCERNS: An 18-year-old boy was transferred to our hospital complaining of a 2-month history of neck pain. DIAGNOSIS: ABC of the thoracic spine INTERVENTIONS:: Six days after SAE, T1 corpectomy was performed via an anterior approach. We performed the operation using the posterior approach 1 week after the anterior approach. Histopathological examination confirmed the diagnosis of ABC. OUTCOMES: No neurologic deterioration occurred during the postoperative period. Follow-up X-rays 2 year postoperative showed good bony fusion and alignment. LESSONS: Primary ABC of the spine is a benign lesion with a potential to be locally aggressive and a high rate of local recurrence. The optimal treatment of thoracic lesions is challenging due to their proximity to the spinal cord and nerve roots, and their frequent association with deformity. Surgical resection/curettage, SAE, and radiotherapy can be used alone or in combination. Complete exposure and resection is crucial to avoid the recurrence. Circumferential fusion and reconstruction of stability are also important for the treatment of thoracic ABC, especially in adolescent patient.

Sensory prediction errors, not performance errors, update memories in visuomotor adaptation.

Sensory prediction errors are thought to update memories in motor adaptation, but the role of performance errors is largely unknown. To dissociate these errors, we manipulated visual feedback during fast shooting movements under visuomotor rotation. Participants were instructed to strategically correct for performance errors by shooting to a neighboring target in one of four conditions: following the movement onset, the main target, the neighboring target, both targets, or none of the targets disappeared. Participants in all conditions experienced a drift away from the main target following the strategy. In conditions where the main target was shown, participants often tried to minimize performance errors caused by the drift by generating corrective movements. However, despite differences in performance during adaptation between conditions, memory decay in a delayed washout block was indistinguishable between conditions. Our results thus suggest that, in visuomotor adaptation, sensory predictions errors, but not performance errors, update the slow, temporally stable, component of motor memory.