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1.
BMC Neurol ; 20(1): 106, 2020 Mar 21.
Article in English | MEDLINE | ID: mdl-32199449

ABSTRACT

BACKGROUND: Psoriasis is the most common chronic inflammatory condition involving the T helper cell system. Population studies have demonstrated that patients with psoriasis and/or psoriatic arthritis have an increased risk of developing vascular risk factors, including diabetes, hypertension, and obesity, and increased risk of adverse vascular events, including myocardial infarction and stroke. Population studies have generally investigated the individual contributions of psoriasis and psoriatic arthritis to development of vascular risk factors; fewer studies have investigated the additive contribution of comorbid inflammatory disorders. We present a case of a woman with psoriasis, psoriatic arthritis, and comorbid vascular risk factors. CASE PRESENTATION: A 49 year-old Caucasian woman with a history of severe psoriasis and psoriatic arthritis since adolescence presented with bilateral lower extremity weakness. She was found to have acute bilateral watershed infarcts and multifocal subacute infarcts. Her evaluation revealed vascular risk factors and elevated non-specific systemic inflammatory markers; serum and cerebral spinal fluid did not reveal underlying infection, hypercoagulable state, or vasculitis. Over the course of days, she exhibited precipitous clinical deterioration related to multiple large vessel occlusions, including the bilateral anterior cerebral arteries and the left middle cerebral artery. Autopsy revealed acute thrombi and diffuse, severe atherosclerosis. CONCLUSION: Patients with early onset inflammatory disease activity or comorbid inflammatory disorders may have an even higher risk of developing metabolic syndrome and adverse vascular events compared to patients with late-onset disease activity or with a single inflammatory condition. The described case illustrates the complex relationship between inflammatory disorders and vascular risk factors. The degree of systemic inflammation, as measured by severity of disease activity, has been shown to have a dose-response relationship with comorbid vascular risk factors and vascular events. Dysregulation of the Th1 and Th17 system has been implicated in the development of atherosclerosis and may explain the severe atherosclerosis seen in such chronic inflammatory conditions. Further research will help refine screening and management guidelines to account for comorbid inflammatory disorders and related disease severity.


Subject(s)
Arthritis, Psoriatic/complications , Psoriasis/complications , Stroke/epidemiology , Arthritis, Psoriatic/immunology , Atherosclerosis/epidemiology , Atherosclerosis/etiology , Comorbidity , Fatal Outcome , Female , Humans , Metabolic Syndrome/epidemiology , Metabolic Syndrome/etiology , Middle Aged , Psoriasis/immunology , Risk Factors
2.
IEEE J Biomed Health Inform ; 24(3): 649-657, 2020 03.
Article in English | MEDLINE | ID: mdl-30951482

ABSTRACT

Early detection of Atrial Fibrillation (AFib) is crucial to prevent stroke recurrence. New tools for monitoring cardiac rhythm are important for risk stratification and stroke prevention. As many of new approaches to long-term AFib detection are now based on photoplethysmogram (PPG) recordings from wearable devices, ensuring high PPG signal-to-noise ratios is a fundamental requirement for a robust detection of AFib episodes. Traditionally, signal quality assessment is often based on the evaluation of similarity between pulses to derive signal quality indices. There are limitations to using this approach for accurate assessment of PPG quality in the presence of arrhythmia, as in the case of AFib, mainly due to substantial changes in pulse morphology. In this paper, we first tested the performance of algorithms selected from a body of studies on PPG quality assessment using a dataset of PPG recordings from patients with AFib. We then propose machine learning approaches for PPG quality assessment in 30-s segments of PPG recording from 13 stroke patients admitted to the University of California San Francisco (UCSF) neuro intensive care unit and another dataset of 3764 patients from one of the five UCSF general intensive care units. We used data acquired from two systems, fingertip PPG (fPPG) from a bedside monitor system, and radial PPG (rPPG) measured using a wearable commercial wristband. We compared various supervised machine learning techniques including k-nearest neighbors, decisions trees, and a two-class support vector machine (SVM). SVM provided the best performance. fPPG signals were used to build the model and achieved 0.9477 accuracy when tested on the data from the fPPG exclusive to the test set, and 0.9589 accuracy when tested on the rPPG data.


Subject(s)
Photoplethysmography/methods , Photoplethysmography/standards , Signal Processing, Computer-Assisted , Supervised Machine Learning , Adult , Aged , Aged, 80 and over , Algorithms , Atrial Fibrillation/diagnosis , Humans , Middle Aged , Oximetry/instrumentation , Stroke , Support Vector Machine , Wearable Electronic Devices , Young Adult
3.
Physiol Meas ; 40(12): 125002, 2019 12 27.
Article in English | MEDLINE | ID: mdl-31766037

ABSTRACT

OBJECTIVE: Photoplethysmography (PPG) monitoring has been implemented in many portable and wearable devices we use daily for health and fitness tracking. Its simplicity and cost-effectiveness has enabled a variety of biomedical applications, such as continuous long-term monitoring of heart arrhythmias, fitness, and sleep tracking, and hydration monitoring. One major issue that can hinder PPG-based applications is movement artifacts, which can lead to false interpretations. In many implementations, noisy PPG signals are discarded. Misinterpreted or discarded PPG signals pose a problem in applications where the goal is to increase the yield of detecting physiological events, such as in the case of paroxysmal atrial fibrillation (AF)-a common episodic heart arrhythmia and a leading risk factor for stroke. In this work, we compared a traditional machine learning and deep learning approaches for PPG quality assessment in the presence of AF, in order to find the most robust method for PPG quality assessment. APPROACH: The training data set was composed of 78 278 30 s long PPG recordings from 3764 patients using bedside patient monitors. Two different representations of PPG signals were employed-a time-series based (1D) one and an image-based (2D) one. Trained models were tested on an independent set of 2683 30 s PPG signals from 13 stroke patients. MAIN RESULTS: ResNet18 showed a higher performance (0.985 accuracy, 0.979 specificity, and 0.988 sensitivity) than SVM and other deep learning approaches. 2D-based models were generally more accurate than 1D-based models. SIGNIFICANCE: 2D representation of PPG signal enhances the accuracy of PPG signal quality assessment.


Subject(s)
Atrial Fibrillation/diagnosis , Deep Learning , Plethysmography , Signal Processing, Computer-Assisted , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Support Vector Machine , Young Adult
4.
Interv Neurol ; 7(5): 256-264, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29765395

ABSTRACT

Intracranial dural arteriovenous fistulae (DAVF) within the deep cerebral vasculature are diagnostically challenging because of their variable clinical presentation and typical bilateral neuroimaging findings mimicking inflammatory, infectious, and metabolic processes. Increasingly, reports have emerged highlighting the diagnostic and treatment challenges of these lesions and their associated high morbidity and rapid clinical deterioration when untreated. We describe here a case series of 4 patients with deep cerebral DAVF who presented with impaired arousal or memory and behavioral changes. In all patients, the initial differential diagnosis included metabolic, inflammatory, infectious, or neoplastic disease, with an eventual correct diagnosis obtained after catheter angiography had demonstrated arterialization of the deep venous structures, including the vein of Galen. All patients were successfully treated with endovascular embolization, with 1 patient requiring additional surgical treatment. We review the contemporary diagnostic evaluation and management of DAVF within the deep cerebral vasculature. With rapid diagnosis and treatment, a favorable outcome is possible.

6.
J Neuroimaging ; 27(3): 300-305, 2017 05.
Article in English | MEDLINE | ID: mdl-28054736

ABSTRACT

With some regularity, we have encountered the unusual imaging abnormality of bilateral hippocampal restricted diffusion, either in isolation or in combination with other coincident abnormalities. In this retrospective case series, we examine clinical and imaging data to explore potential etiologies and clinical implications of this imaging finding. Sixteen cases with the imaging abnormality are presented, with etiologies including hypoxemia, hypoxemia-ischemia, and seizures.


Subject(s)
Hippocampus/diagnostic imaging , Hypoxia/diagnostic imaging , Ischemia/diagnostic imaging , Seizures/diagnostic imaging , Adult , Aged , Aged, 80 and over , Diffusion Magnetic Resonance Imaging/methods , Female , Hippocampus/blood supply , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , Retrospective Studies , Young Adult
10.
J Neurovirol ; 22(1): 125-8, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26306687

ABSTRACT

Chikungunya virus (CHIKV) is a mosquito-borne alphavirus that is endemic to parts of Africa, South and Southeast Asia, and more recently the Caribbean. Patients typically present with fever, rash, and arthralgias, though neurologic symptoms, primarily encephalitis, have been described. We report the case of a 47-year-old woman who was clinically diagnosed with CHIKV while traveling in the Dominican Republic and presented 10 days later with left lower extremity weakness, a corresponding enhancing thoracic spinal cord lesion, and positive CHIKV serologies. She initially responded to corticosteroids, followed by relapsing symptoms and gradual clinical improvement. The time lapse between acute CHIKV infection and the onset of myelopathic sequelae suggests an immune-mediated phenomenon rather than direct activity of the virus itself. Chikungunya virus should be considered in the differential diagnosis of myelopathy in endemic areas. The progression of symptoms despite corticosteroid administration suggests more aggressive immunomodulatory therapies may be warranted at disease onset.


Subject(s)
Chikungunya Fever/diagnosis , Neuralgia/diagnosis , Radiculopathy/diagnosis , Spinal Cord Diseases/diagnosis , Adrenal Cortex Hormones/therapeutic use , Chikungunya Fever/complications , Chikungunya Fever/drug therapy , Chikungunya Fever/physiopathology , Chikungunya virus/pathogenicity , Chikungunya virus/physiology , Dominican Republic , Female , Humans , Methylprednisolone/therapeutic use , Middle Aged , Neuralgia/complications , Neuralgia/drug therapy , Neuralgia/physiopathology , Radiculopathy/complications , Radiculopathy/drug therapy , Radiculopathy/physiopathology , Spinal Cord/drug effects , Spinal Cord/physiopathology , Spinal Cord/virology , Spinal Cord Diseases/complications , Spinal Cord Diseases/drug therapy , Spinal Cord Diseases/physiopathology , Travel , United States
11.
Neuroimage ; 59(1): 573-81, 2012 Jan 02.
Article in English | MEDLINE | ID: mdl-21840409

ABSTRACT

While the majority of individuals with multiple sclerosis (MS) develop significant clinical disability, a subset experiences a disease course with minimal impairment even in the presence of significant apparent tissue damage on magnetic resonance imaging (MRI). Functional magnetic resonance imaging (fMRI) in MS patients with low disability suggests that increased use of the cognitive control system may limit the clinical manifestation of the disease. The current fMRI studies tested the hypothesis that nondisabled MS patients show increased recruitment of cognitive control regions while performing sensory, motor and cognitive tasks. Twenty two patients with relapsing-remitting MS and an Expanded Disability Status Scale (EDSS) score of ≤1.5 and 23 matched healthy controls were recruited. Subjects underwent fMRI while observing flashing checkerboards, performing right or left hand movements, or executing the 2-back working memory task. Compared to control subjects, patients demonstrated increased activation of the right dorsolateral prefrontal cortex and anterior cingulate cortex during the performance of the working memory task. This pattern of functional recruitment also was observed during the performance of non-dominant hand movements. These results support the mounting evidence of increased functional recruitment of cognitive control regions in the working memory system of MS patients with low disability and provide new evidence for the role of increased cognitive control recruitment in the motor system.


Subject(s)
Brain Mapping , Brain/physiopathology , Multiple Sclerosis, Relapsing-Remitting/physiopathology , Adult , Female , Humans , Image Interpretation, Computer-Assisted , Magnetic Resonance Imaging , Male , Memory, Short-Term/physiology , Psychomotor Performance/physiology
12.
Brain Res ; 1343: 218-25, 2010 Jul 09.
Article in English | MEDLINE | ID: mdl-20470763

ABSTRACT

Antidepressants require adaptive brain changes before efficacy is achieved, and they may impact the affectively disordered brain differently than the normal brain. We previously demonstrated metabolic disturbances in limbic and cortical regions of the congenitally helpless rat, a model of susceptibility to affective disorder, and we wished to test whether administration of fluoxetine would normalize these metabolic differences. Fluoxetine was chosen because it has become a first-line drug for the treatment of affective disorders. We hypothesized that fluoxetine antidepressant effects may be mediated by decreasing metabolism in the habenula and increasing metabolism in the ventral tegmental area. We measured the effects of fluoxetine on forced swim behavior and regional brain cytochrome oxidase activity in congenitally helpless rats treated for 2 weeks with fluoxetine (5mg/kg, i.p., daily). Fluoxetine reduced immobility in the forced swim test as anticipated, but congenitally helpless rats responded in an atypical manner, i.e., increasing climbing without affecting swimming. As hypothesized, fluoxetine reduced metabolism in the habenula and increased metabolism in the ventral tegmental area. In addition, fluoxetine reduced the metabolism of the hippocampal dentate gyrus and dorsomedial prefrontal cortex. This study provided the first detailed mapping of the regional brain effects of an antidepressant drug in congenitally helpless rats. All of the effects were consistent with previous studies that have metabolically mapped the effects of serotonergic antidepressants in the normal rat brain, and were in the predicted direction of metabolic normalization of the congenitally helpless rat for all affected brain regions except the prefrontal cortex.


Subject(s)
Brain/drug effects , Brain/metabolism , Depressive Disorder/drug therapy , Depressive Disorder/metabolism , Energy Metabolism/drug effects , Fluoxetine/pharmacology , Animals , Antidepressive Agents, Second-Generation/pharmacology , Brain/physiopathology , Brain Mapping/methods , Depressive Disorder/genetics , Disease Models, Animal , Electron Transport Complex IV/metabolism , Energy Metabolism/physiology , Male , Rats , Rats, Inbred Strains , Selective Serotonin Reuptake Inhibitors/pharmacology , Swimming/psychology
13.
Dev Psychobiol ; 51(3): 277-88, 2009 Apr.
Article in English | MEDLINE | ID: mdl-19125421

ABSTRACT

We tested the hypothesis that adolescent Sprague-Dawley females may be more resistant than males to display impulsive behavior and lower prefrontal cortex thickness after mother-infant separation (MS). Starting at postnatal day 2 (P2), the MS group was separated 6 hr/day and the early handled (EH) group 15 min/day for 10 days, and another group was standard facility reared (SFR). Subjects were examined for novel open-field activity (P28), light-dark apparatus (P29), familiar open-field (P30) and frontal cortical thickness. This protocol resulted in impulsive behavior in MS rats relative to EH and SFR, but this effect was less pronounced in females than males. MS affected the two sexes differently in terms of decreased prefrontal cortex dorsoventral thickness, with this effect being significant in males but not females. Neuroanatomical and behavioral documentation that adolescent females are more resistant than males to ADHD-like effects of maternal separation have not been previously reported.


Subject(s)
Arousal/physiology , Impulsive Behavior/pathology , Maternal Deprivation , Prefrontal Cortex/pathology , Sex Characteristics , Animals , Fear/physiology , Female , Humans , Male , Motor Activity/physiology , Organ Size/physiology , Rats , Rats, Sprague-Dawley , Sexual Maturation/physiology , Social Environment
14.
Neurosci Lett ; 440(3): 255-9, 2008 Aug 08.
Article in English | MEDLINE | ID: mdl-18579304

ABSTRACT

The juvenile brain undergoes marked maturational changes accompanied by major sex hormone changes. In particular, sex differences in neural substrates could underlie male-specific dysfunction in behavioral responses related to the prefrontal cortex. Sex differences in regional metabolic capacity of the cerebral cortex were investigated in juvenile Sprague-Dawley rats. At 6 weeks of age the brains were processed for quantitative histochemistry of cytochrome oxidase, a rate-limiting enzyme in cellular respiration, which is an index of brain metabolic capacity. Quantitative image analysis revealed a main effect of sex with males displaying lower regional metabolic capacity than females in the dorsolateral and orbital prefrontal cortex and in the posterior parietal cortex. In addition, males separated for 6 h/day from their mothers as pups showed greater ambulatory behavior in the novel open field and higher metabolism in the posterior parietal cortex relative to males separated for 15 min/day. This is the first study to show sex differences in brain metabolic capacity in regions such as the prefrontal cortex that may be hypometabolic in juvenile males relative to females.


Subject(s)
Cerebral Cortex/growth & development , Cerebral Cortex/metabolism , Sex Characteristics , Age Factors , Animals , Animals, Newborn , Behavior, Animal/physiology , Cerebral Cortex/anatomy & histology , Electron Transport Complex IV/metabolism , Exploratory Behavior/physiology , Female , Male , Rats , Rats, Sprague-Dawley
16.
Behav Processes ; 71(1): 51-8, 2006 Jan 10.
Article in English | MEDLINE | ID: mdl-16242858

ABSTRACT

Effects of maternal separation in rats have been extensively investigated, but no studies have examined its effects in rat adolescence. We examined the effects of neonatal infant-mother separation (MS) for 6h/day and early handling (EH) for 10 days during the first 2 weeks of life by comparing MS and EH groups to standard facility reared (SFR) controls. At adolescence, the animals were evaluated in a novel and familiar open-field, the light-dark box, and the sucrose consumption test. Behavioral indices included orienting behavior (rearing frequency and duration), impulsive behavior (movement velocity and risk taking by entering the center of the open field or the light compartment of the light-dark box), hyperactivity (ambulatory distance and stereotypic movement), and reward-seeking behavior (sucrose drinking time). The prolonged MS during the first 2 weeks of life resulted in decreased orienting behavior and increased impulsive behavior in adolescence. Measures of ambulatory and stereotypic movements showed that MS rats were hyperactive in the novel environment whereas EH rats were less active overall. The impulsive/hyperactive phenotype produced by this MS protocol may provide a useful animal model to investigate the neurological basis for the similar behavioral phenotype found in attention deficit/hyperactivity disorder.


Subject(s)
Behavior, Animal/physiology , Impulsive Behavior/psychology , Maternal Behavior/physiology , Maternal Deprivation , Orientation/physiology , Space Perception/physiology , Age Factors , Animals , Animals, Newborn , Attention Deficit Disorder with Hyperactivity/psychology , Disease Models, Animal , Female , Rats , Rats, Sprague-Dawley
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