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1.
Mol Psychiatry ; 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38664492

ABSTRACT

With advances in our understanding regarding the neurochemical underpinnings of neurological and psychiatric diseases, there is an increased demand for advanced computational methods for neurochemical analysis. Despite having a variety of techniques for measuring tonic extracellular concentrations of neurotransmitters, including voltammetry, enzyme-based sensors, amperometry, and in vivo microdialysis, there is currently no means to resolve concentrations of structurally similar neurotransmitters from mixtures in the in vivo environment with high spatiotemporal resolution and limited tissue damage. Since a variety of research and clinical investigations involve brain regions containing electrochemically similar monoamines, such as dopamine and norepinephrine, developing a model to resolve the respective contributions of these neurotransmitters is of vital importance. Here we have developed a deep learning network, DiscrimNet, a convolutional autoencoder capable of accurately predicting individual tonic concentrations of dopamine, norepinephrine, and serotonin from both in vitro mixtures and the in vivo environment in anesthetized rats, measured using voltammetry. The architecture of DiscrimNet is described, and its ability to accurately predict in vitro and unseen in vivo concentrations is shown to vastly outperform a variety of shallow learning algorithms previously used for neurotransmitter discrimination. DiscrimNet is shown to generalize well to data captured from electrodes unseen during model training, eliminating the need to retrain the model for each new electrode. DiscrimNet is also shown to accurately predict the expected changes in dopamine and serotonin after cocaine and oxycodone administration in anesthetized rats in vivo. DiscrimNet therefore offers an exciting new method for real-time resolution of in vivo voltammetric signals into component neurotransmitters.

2.
Circulation ; 148(3): 229-240, 2023 07 18.
Article in English | MEDLINE | ID: mdl-37459415

ABSTRACT

BACKGROUND: Systems of care have been developed across the United States to standardize care processes and improve outcomes in patients with ST-segment-elevation myocardial infarction (STEMI). The effect of contemporary STEMI systems of care on racial and ethnic disparities in achievement of time-to-treatment goals and mortality in STEMI is uncertain. METHODS: We analyzed 178 062 patients with STEMI (52 293 women and 125 769 men) enrolled in the American Heart Association Get With The Guidelines-Coronary Artery Disease registry between January 1, 2015, and December 31, 2021. Patients were stratified into and outcomes compared among 3 racial and ethnic groups: non-Hispanic White, Hispanic White, and Black. The primary outcomes were the proportions of patients achieving the following STEMI process metrics: prehospital ECG obtained by emergency medical services; hospital arrival to ECG obtained within 10 minutes for patients not transported by emergency medical services; arrival-to-percutaneous coronary intervention time within 90 minutes; and first medical contact-to-device time within 90 minutes. A secondary outcome was in-hospital mortality. Analyses were performed separately in women and men, and all outcomes were adjusted for age, comorbidities, acuity of presentation, insurance status, and socioeconomic status measured by social vulnerability index based on patients' county of residence. RESULTS: Compared with non-Hispanic White patients with STEMI, Hispanic White patients and Black patients had lower odds of receiving a prehospital ECG and achieving targets for door-to-ECG, door-to-device, and first medical contact-to-device times. These racial disparities in treatment goals were observed in both women and men, and persisted in most cases after multivariable adjustment. Compared with non-Hispanic White women, Hispanic White women had higher adjusted in-hospital mortality (odds ratio, 1.39 [95% CI, 1.12-1.72]), whereas Black women did not (odds ratio, 0.88 [95% CI, 0.74-1.03]). Compared with non-Hispanic White men, adjusted in-hospital mortality was similar in Hispanic White men (odds ratio, 0.99 [95% CI, 0.82-1.18]) and Black men (odds ratio, 0.96 [95% CI, 0.85-1.09]). CONCLUSIONS: Race- or ethnicity-based disparities persist in STEMI process metrics in both women and men, and mortality differences are observed in Hispanic White compared with non-Hispanic White women. Further research is essential to evolve systems of care to mitigate racial differences in STEMI outcomes.


Subject(s)
Coronary Artery Disease , Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Male , Humans , Female , United States/epidemiology , ST Elevation Myocardial Infarction/diagnosis , ST Elevation Myocardial Infarction/therapy , ST Elevation Myocardial Infarction/etiology , Coronary Artery Disease/etiology , American Heart Association , Percutaneous Coronary Intervention/adverse effects , Hospital Mortality , Registries
3.
Brain ; 146(10): 4174-4190, 2023 10 03.
Article in English | MEDLINE | ID: mdl-37141283

ABSTRACT

Tourette syndrome is a childhood-onset neuropsychiatric disorder characterized by intrusive motor and vocal tics that can lead to self-injury and deleterious mental health complications. While dysfunction in striatal dopamine neurotransmission has been proposed to underlie tic behaviour, evidence is scarce and inconclusive. Deep brain stimulation (DBS) of the thalamic centromedian parafascicular complex (CMPf), an approved surgical interventive treatment for medical refractory Tourette syndrome, may reduce tics by affecting striatal dopamine release. Here, we use electrophysiology, electrochemistry, optogenetics, pharmacological treatments and behavioural measurements to mechanistically examine how thalamic DBS modulates synaptic and tonic dopamine activity in the dorsomedial striatum. Previous studies demonstrated focal disruption of GABAergic transmission in the dorsolateral striatum of rats led to repetitive motor tics recapitulating the major symptom of Tourette syndrome. We employed this model under light anaesthesia and found CMPf DBS evoked synaptic dopamine release and elevated tonic dopamine levels via striatal cholinergic interneurons while concomitantly reducing motor tic behaviour. The improvement in tic behaviour was found to be mediated by D2 receptor activation as blocking this receptor prevented the therapeutic response. Our results demonstrate that release of striatal dopamine mediates the therapeutic effects of CMPf DBS and points to striatal dopamine dysfunction as a driver for motor tics in the pathoneurophysiology of Tourette syndrome.


Subject(s)
Deep Brain Stimulation , Tics , Tourette Syndrome , Humans , Rats , Animals , Child , Tics/therapy , Tourette Syndrome/therapy , Dopamine , Deep Brain Stimulation/methods , Thalamus
4.
J Neurophysiol ; 127(3): 714-724, 2022 03 01.
Article in English | MEDLINE | ID: mdl-34986049

ABSTRACT

Although dopamine is the most implicated neurotransmitter in the mediation of the pathophysiology of addiction, animal studies show serotonin also plays a vital role. Cocaine is one of the most common illicit drugs globally, but the role of serotonin in its mechanism of action is insufficiently characterized. Consequently, we investigated the acute effects of the psychomotor stimulant cocaine on electrical stimulation-evoked serotonin (phasic) release in the nucleus accumbens core (NAcc) of urethane-anesthetized (1.5 g/kg ip) male Sprague-Dawley rats using N-shaped fast-scan cyclic voltammetry (N-FSCV). A single carbon fiber microelectrode was first implanted in the NAcc. Stimulation was applied to the medial forebrain bundle using 60 Hz, 2 ms, 0.2 mA, 2-s biphasic pulses before and after cocaine (2 mg/kg iv) was administered. Stimulation-evoked serotonin release significantly increased 5 min after cocaine injection compared with baseline (153 ± 21 nM vs. 257 ± 12 nM; P = 0.0042; n = 5) but was unaffected by saline injection (1 mL/kg iv; n = 5). N-FSCV's selective measurement of serotonin release in vivo was confirmed pharmacologically via administration of the selective serotonin reuptake inhibitor escitalopram (10 mg/kg ip) that effectively increased the signal in a separate group of rats (n = 5). Selectivity to serotonin was further confirmed in vitro in which dopamine was minimally detected by N-FSCV with a serotonin to dopamine response ratio of 1:0.04 (200 nM of serotonin:1 µM dopamine ratio; P = 0.0048; n = 5 electrodes). This study demonstrates a noteworthy influence of cocaine on serotonin dynamics, and confirms that N-FSCV can effectively and selectively measure phasic serotonin release in the NAcc.NEW & NOTEWORTHY Serotonin plays a vital role in drug addiction. Here, using N-shaped fast-scan cyclic voltammetry, we demonstrated the effect of cocaine on the phasic release of serotonin at the nucleus accumbens core. To the best of our knowledge, this has not previously been elucidated. Our results not only reinforce the role of serotonin in the mechanism of action of cocaine but also help to fill a gap in our knowledge and provide a baseline for future studies in cocaine addiction.


Subject(s)
Cocaine , Nucleus Accumbens , Animals , Cocaine/pharmacology , Dopamine/pharmacology , Electric Stimulation , Male , Rats , Rats, Sprague-Dawley , Serotonin/pharmacology
5.
J Clin Microbiol ; 60(11): e0119622, 2022 Nov 16.
Article in English | MEDLINE | ID: mdl-36214584

ABSTRACT

Serratia marcescens can cause a range of severe infections and contributes to nosocomial outbreaks. Although whole-genome sequencing (WGS)-based typing is the standard method for molecular surveillance and outbreak investigation, there is no standardized analytic scheme for S. marcescens core genome multilocus sequence typing (cgMLST). Here, the development and evaluation of a S. marcescens cgMLST scheme is reported with the goal of enabling a standardized methodology and typing nomenclature. Four hundred ninety-one high-quality S. marcescens WGS data sets were extracted from public databases and-using the genomic sequence of NCBI reference strain S. marcescens Db11 (NZ_HG326223.1) as a starting point-all Db11 genes present in ≥97% data sets used to create a cgMLST scheme. The novel scheme was evaluated using WGS data from 24 outbreak investigations (n = 175 isolates) distributed over three continents. Analysis of Db11 genes within the 491 data sets identified 2,692 target genes present in ≥97% of genomes (mean, 99.1%; median, 99.9%). These genes formed the novel cgMLST scheme, covering 47.8% of nucleotides in the Db11 genome. Analyzing 175 isolates from 24 outbreaks using the novel scheme gave comparable results to previous typing efforts for both general groupings and allelic distances within clusters. In summary, a novel cgMLST scheme for S. marcescens was developed and evaluated. The scheme and its associated nomenclature will improve standardization of typing efforts for molecular surveillance and outbreak investigation, allowing better understanding of S. marcescens genomic epidemiology and facilitating interlaboratory comparisons.


Subject(s)
Genome, Bacterial , Serratia marcescens , Humans , Multilocus Sequence Typing/methods , Serratia marcescens/genetics , Genome, Bacterial/genetics , Disease Outbreaks , Whole Genome Sequencing/methods
6.
Am Heart J ; 249: 34-44, 2022 07.
Article in English | MEDLINE | ID: mdl-35339451

ABSTRACT

BACKGROUND: Little is known about the prevalence and prognostic impact of preexisting frailty on acute care and in-hospital outcomes in older adults in the setting of acute myocardial infarction (AMI). METHODS: Preexisting frailty was assessed at baseline in consecutive AMI patients ≥65 years of age treated at 778 hospitals participating in the NCDR ACTION Registry between January 1, 2015 to December 31, 2016. Three domains of preexisting frailty (cognition, ambulation, and functional independence) were abstracted from chart review and summed in 2 ways: an ACTION Frailty Scale based on responses to 6 groups adapted from the Canadian Study of Health and Aging Clinical Frailty Scale and an ACTION Frailty Score derived by summing a rank score of 0-2 assigned for each grade (total ranged between 0 to 6). Multivariable logistic regression examined the association between assigned frailty by score or scale and in-hospital mortality. RESULTS: Among 143,722 older AMI patients, 108,059 (75.2%) were fit and/or well and 6,484 (4.5%) were vulnerable to frailty, while 7,527 (5.2%) had mild, 3,913 (2.7%) had moderate, 2,715 had (1.9%) severe, and 632 (0.4%) had very severe frailty according to the ACTION Frailty Scale, while 14,392 (10.0%) could not be categorized due to incomplete ascertainment. Frail patients were older, more frequently female, of non-white race and/or ethnicity, and less likely to be treated with guideline-recommended therapies. Increasing severity of frailty by this scale was associated with a step-wise higher risk for in-hospital mortality (P-trend < .001). Patient categories of the ACTION Frailty Score provided similar results. After adjustment, each 1-unit increase in Frailty Score was associated with a 12% higher mortality risk (OR 1.12, 95% CI 1.10-1.15). CONCLUSIONS: Among older patients with acute myocardial infarction, frailty is common and independently associated with in-hospital mortality. These findings show the importance of pragmatic evaluation of frailty in hospital-level quality scores, guideline recommendations, and incorporation into other registry data collection efforts.


Subject(s)
Frailty , Myocardial Infarction , Aged , Canada/epidemiology , Female , Frail Elderly , Frailty/complications , Frailty/epidemiology , Hospital Mortality , Humans , Myocardial Infarction/complications , Myocardial Infarction/epidemiology , Registries
7.
Int J Obes (Lond) ; 46(12): 2163-2167, 2022 12.
Article in English | MEDLINE | ID: mdl-36008680

ABSTRACT

Despite its cardiometabolic benefits, bariatric surgery has historically been underused in patients with obesity and diabetes, but contemporary data are lacking. Among 1,520,182 patients evaluated from 2013 to 2019 within a multicenter, longitudinal, US registry of outpatients with diabetes, we found that 462,033 (30%) met eligibility for bariatric surgery. After a median follow-up of 854 days, 6310/384,859 patients (1.6%) underwent primary bariatric surgery, with a slight increase over time (0.38% per year [2013] to 0.68% per year [2018]). Patients who underwent bariatric surgery were more likely to be female (63% vs. 56%), white (87% vs. 82%), have higher body mass indices (42.1 ± 6.9 vs. 40.6 ± 5.9 kg/m2), and depression (23% vs. 14%; p < 0.001 for all). Over a median (IQR) follow-up after surgery of 722 days (364-993), patients who underwent bariatric surgery had lost an average of 11.8 ± 18.5 kg (23% of excess body weight), 10.2% were on fewer glucose-lowering medications, and 8.4% were on fewer antihypertensives. Despite bariatric surgery being safer and more accessible over the past two decades, less than one in fifty eligible patients with diabetes receive this therapy.


Subject(s)
Bariatric Surgery , Diabetes Mellitus, Type 2 , Diabetes Mellitus , Obesity, Morbid , Humans , Female , Male , Weight Loss , Bariatric Surgery/adverse effects , Obesity/complications , Obesity/epidemiology , Obesity/surgery , Registries , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/surgery , Obesity, Morbid/complications , Obesity, Morbid/epidemiology , Obesity, Morbid/surgery , Retrospective Studies
8.
JAMA ; 328(20): 2033-2040, 2022 11 22.
Article in English | MEDLINE | ID: mdl-36335474

ABSTRACT

Importance: Recognizing the association between timely treatment and less myocardial injury for patients with ST-segment elevation myocardial infarction (STEMI), US national guidelines recommend specific treatment-time goals. Objective: To describe these process measures and outcomes for a recent cohort of patients. Design, Setting, and Participants: Cross-sectional study of a diagnosis-based registry between the second quarter of 2018 and the third quarter of 2021 for 114 871 patients with STEMI treated at 648 hospitals in the Get With The Guidelines-Coronary Artery Disease registry. Exposures: STEMI or STEMI equivalent. Main Outcomes and Measures: Treatment times, in-hospital mortality, and adherence to system goals (75% treated ≤90 minutes of first medical contact if the first hospital is percutaneous coronary intervention [PCI]-capable and ≤120 minutes if patients require transfer to a PCI-capable hospital). Results: In the study population, median age was 63 (IQR, 54-72) years, 71% were men, and 29% were women. Median time from symptom onset to PCI was 148 minutes (IQR, 111-226) for patients presenting to PCI-capable hospitals by emergency medical service, 195 minutes (IQR, 127-349) for patients walking in, and 240 minutes (IQR, 166-402) for patients transferred from another hospital. Adjusted in-hospital mortality was lower for those treated within target times vs beyond time goals for patients transported via emergency medical services (first medical contact to laboratory activation ≤20 minutes [in-hospital mortality, 3.6 vs 9.2] adjusted OR, 0.54 [95% CI, 0.48-0.60], and first medical contact to device ≤90 minutes [in-hospital mortality, 3.3 vs 12.1] adjusted OR, 0.40 [95% CI, 0.36-0.44]), walk-in patients (hospital arrival to device ≤90 minutes [in-hospital mortality, 1.8 vs 4.7] adjusted OR, 0.47 [95% CI, 0.40-0.55]), and transferred patients (door-in to door-out time <30 minutes [in-hospital mortality, 2.9 vs 6.4] adjusted OR, 0.51 [95% CI, 0.32-0.78], and first hospital arrival to device ≤120 minutes [in-hospital mortality, 4.3 vs 14.2] adjusted OR, 0.44 [95% CI, 0.26-0.71]). Regardless of mode of presentation, system goals were not met in most quarters, with the most delayed system performance among patients requiring interhospital transfer (17% treated ≤120 minutes). Conclusions and Relevance: This study of patients with STEMI included in a US national registry provides information on changes in process and outcomes between 2018 and 2021.


Subject(s)
Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Male , Humans , Female , Middle Aged , ST Elevation Myocardial Infarction/therapy , Percutaneous Coronary Intervention/adverse effects , Hospital Mortality , Time-to-Treatment , Cross-Sectional Studies , Patient Transfer , Time Factors
9.
Anal Chem ; 93(51): 16987-16994, 2021 12 28.
Article in English | MEDLINE | ID: mdl-34855368

ABSTRACT

Here, we present the development of a novel voltammetric technique, N-shaped multiple cyclic square wave voltammetry (N-MCSWV) and its application in vivo. It allows quantitative measurements of tonic extracellular levels of serotonin in vivo with mitigated fouling effects. N-MCSWV enriches the electrochemical information by generating high dimensional voltammograms, which enables high sensitivity and selectivity against 5-hydroindoleacetic acid (5-HIAA), dopamine, 3,4-dihydroxyphenylacetic acid (DOPAC), histamine, ascorbic acid, norepinephrine, adenosine, and pH. Using N-MCSWV, in combination with PEDOT:Nafion-coated carbon fiber microelectrodes, a tonic serotonin concentration of 52 ± 5.8 nM (n = 20 rats, ±SEM) was determined in the substantia nigra pars reticulata of urethane-anesthetized rats. Pharmacological challenges with dopaminergic, noradrenergic, and serotonergic synaptic reuptake inhibitors supported the ability of N-MCSWV to selectively detect tonic serotonin levels in vivo. Overall, N-MCSWV is a novel voltammetric technique for analytical quantification of serotonin. It offers continuous monitoring of changes in tonic serotonin concentrations in the brain to further our understanding of the role of serotonin in normal behaviors and psychiatric disorders.


Subject(s)
Dopamine , Serotonin , Animals , Brain Chemistry , Microelectrodes , Rats , Rats, Sprague-Dawley , Serotonin/metabolism
10.
Cardiovasc Diabetol ; 19(1): 212, 2020 12 12.
Article in English | MEDLINE | ID: mdl-33308233

ABSTRACT

BACKGROUND: Heart failure is a common and devastating complication of type 2 diabetes (T2D). Prompt recognition of heart failure may avert hospitalization, facilitate use of guideline-directed therapies, and impact choice of T2D medications. We sought to determine the rate and factors associated with heart failure documentation in T2D patients with evidence of volume overload requiring loop diuretics. METHODS: DCR is an on-going, prospective US registry of outpatient T2D patients from > 5000 cardiology, endocrinology, and primary care clinicians (current analysis used data from 2013-2019). Among T2D patients receiving loop diuretics, we examined the rate of chart documentation of heart failure. We used a 3-level hierarchical logistic regression model (patients nested within physician within practice) to examine factors associated with heart failure diagnosis. RESULTS: Among 1,322,640 adults with T2D, 225,125 (17.0%) were receiving a loop diuretic, of whom 91,969 (40.9%) had documentation of heart failure. Male sex, lower body mass index, atrial fibrillation, chronic kidney disease, and coronary artery disease were associated with greater odds of heart failure diagnosis. After accounting for patient factors, patients seen by cardiologists were the most likely to have HF documented followed by PCPs and then endocrinologists. CONCLUSIONS: Among US outpatients with T2D, 17% of patients had evidence of volume overload-defined by loop diuretic prescription-of whom fewer than half had a clinical diagnosis of heart failure. While there may be non-heart failure indications for loop diuretics, our data suggest that a substantial proportion of T2D patients may have unrecognized heart failure and therefore could be missing opportunities for targeted therapies that could alter the clinical course of heart failure.


Subject(s)
Cardiac Output , Diabetes Mellitus, Type 2/diagnosis , Documentation , Heart Failure/diagnosis , Outpatients , Aged , Aged, 80 and over , Cardiac Output/drug effects , Diabetes Mellitus, Type 2/epidemiology , Electronic Health Records , Female , Heart Failure/drug therapy , Heart Failure/epidemiology , Heart Failure/physiopathology , Humans , Male , Middle Aged , Prognosis , Quality Indicators, Health Care , Registries , Risk Assessment , Risk Factors , Sodium Potassium Chloride Symporter Inhibitors/therapeutic use , United States/epidemiology
11.
Clin Transplant ; 34(12): e14083, 2020 12.
Article in English | MEDLINE | ID: mdl-32946629

ABSTRACT

INTRODUCTION: Chronic kidney disease is an independent risk factor for cardiovascular disease. Despite careful preoperative evaluation, there is a risk of acute coronary syndromes after kidney transplant. METHODS: The National Inpatient Sample for the years 2004-2013 was used for this retrospective cohort study. All adult patients undergoing kidney transplantation were identified using the appropriate ICD-9-CM codes. Multivariate logistic regression was used to identify predictors of acute coronary syndromes in the peri-operative period after kidney transplantation. RESULTS: A total of 147 431 kidney transplants were performed from 2004 through 2013 in the United States. The average peri-operative in-hospital mortality was 0.5%. Acute coronary syndrome occurred in 1.3% patients in the peri-operative period. Half of patients with acute coronary syndromes had pre-existing coronary artery disease. The strongest predictors of acute coronary syndromes included older age: 45-64 years. OR 3.28 95% CI (1.85-5.83), ≥65 years. OR 4.84 (2.59-9.05), race: African American, OR 0.66 (0.47-0.93) and pre-existing coronary artery disease OR 3.83 (2.84-5.15). The case fatality rates were 16.9% and 5.3% for STEMI and NSTEMI, respectively. The overall mortality for any ACS event was 7.1%. CONCLUSION: Acute coronary syndrome in the immediate peri-operative period after kidney transplantation is rare but is associated with high rates of mortality.


Subject(s)
Acute Coronary Syndrome , Kidney Transplantation , Non-ST Elevated Myocardial Infarction , Acute Coronary Syndrome/epidemiology , Acute Coronary Syndrome/etiology , Adult , Aged , Hospital Mortality , Humans , Kidney Transplantation/adverse effects , Retrospective Studies , Risk Factors , Time Factors , United States/epidemiology
12.
Neurosurg Focus ; 49(1): E8, 2020 07.
Article in English | MEDLINE | ID: mdl-32610293

ABSTRACT

The thalamic ventral intermediate nucleus (VIM) can be targeted for treatment of tremor by several procedures, including deep brain stimulation (DBS) and, more recently, MR-guided focused ultrasound (MRgFUS). To date, such targeting has relied predominantly on coordinate-based or atlas-based techniques rather than directly targeting the VIM based on imaging features. While general regional differences of features within the thalamus and some related white matter tracts can be distinguished with conventional imaging techniques, internal nuclei such as the VIM are not discretely visualized. Advanced imaging methods such as quantitative susceptibility mapping (QSM) and fast gray matter acquisition T1 inversion recovery (FGATIR) MRI and high-field MRI pulse sequences that improve the ability to image the VIM region are emerging but have not yet been shown to have reliability and accuracy to serve as the primary method of VIM targeting. Currently, the most promising imaging approach to directly identify the VIM region for clinical purposes is MR diffusion tractography.In this review and update, the capabilities and limitations of conventional and emerging advanced methods for evaluation of internal thalamic anatomy are briefly reviewed. The basic principles of tractography most relevant to VIM targeting are provided for familiarization. Next, the key literature to date addressing applications of DTI and tractography for DBS and MRgFUS is summarized, emphasizing use of direct targeting. This literature includes 1-tract (dentatorubrothalamic tract [DRT]), 2-tract (pyramidal and somatosensory), and 3-tract (DRT, pyramidal, and somatosensory) approaches to VIM region localization through tractography.The authors introduce a 3-tract technique used at their institution, illustrating the oblique curved course of the DRT within the inferior thalamus as well as the orientation and relationship of the white matter tracts in the axial plane. The utility of this 3-tract tractography approach to facilitate VIM localization is illustrated with case examples of variable VIM location, targeting superior to the anterior commissure-posterior commissure plane, and treatment in the setting of pathologic derangement of thalamic anatomy. Finally, concepts demonstrated with these case examples and from the prior literature are synthesized to highlight several potential advantages of tractography for VIM region targeting.


Subject(s)
Deep Brain Stimulation , Essential Tremor/therapy , Parkinson Disease/therapy , Ultrasonography , Deep Brain Stimulation/methods , Diffusion Tensor Imaging/methods , Gray Matter/physiopathology , Humans , Magnetic Resonance Imaging/methods , Reproducibility of Results , Thalamus/diagnostic imaging , Ultrasonography/methods , White Matter/physiopathology
13.
Rev Anal Chem ; 39(1): 188-199, 2020.
Article in English | MEDLINE | ID: mdl-33883813

ABSTRACT

Neurochemical recording techniques have expanded our understanding of the pathophysiology of neurological disorders, as well as the mechanisms of action of treatment modalities like deep brain stimulation (DBS). DBS is used to treat diseases such as Parkinson's disease, Tourette syndrome, and obsessive-compulsive disorder, among others. Although DBS is effective at alleviating symptoms related to these diseases and improving the quality of life of these patients, the mechanism of action of DBS is currently not fully understood. A leading hypothesis is that DBS modulates the electrical field potential by modifying neuronal firing frequencies to non-pathological rates thus providing therapeutic relief. To address this gap in knowledge, recent advances in electrochemical sensing techniques have given insight into the importance of neurotransmitters, such as dopamine, serotonin, glutamate, and adenosine, in disease pathophysiology. These studies have also highlighted their potential use in tandem with electrophysiology to serve as biomarkers in disease diagnosis and progression monitoring, as well as characterize response to treatment. Here, we provide an overview of disease-relevant neurotransmitters and their roles and implications as biomarkers, as well as innovations to the biosensors used to record these biomarkers. Furthermore, we discuss currently available neurochemical and electrophysiological recording devices, and discuss their viability to be implemented into the development of a closed-loop DBS system.

14.
J Neurosci ; 38(19): 4471-4481, 2018 05 09.
Article in English | MEDLINE | ID: mdl-29636396

ABSTRACT

The medial temporal lobe (MTL) is widely implicated in supporting episodic memory and navigation, but its precise functional role in organizing memory across time and space remains elusive. Here we examine the specific cognitive processes implemented by MTL structures (hippocampus and entorhinal cortex) to organize memory by using electrical brain stimulation, leveraging its ability to establish causal links between brain regions and features of behavior. We studied neurosurgical patients of both sexes who performed spatial-navigation and verbal-episodic memory tasks while brain stimulation was applied in various regions during learning. During the verbal memory task, stimulation in the MTL disrupted the temporal organization of encoded memories such that items learned with stimulation tended to be recalled in a more randomized order. During the spatial task, MTL stimulation impaired subjects' abilities to remember items located far away from boundaries. These stimulation effects were specific to the MTL. Our findings thus provide the first causal demonstration in humans of the specific memory processes that are performed by the MTL to encode when and where events occurred.SIGNIFICANCE STATEMENT Numerous studies have implicated the medial temporal lobe (MTL) in encoding spatial and temporal memories, but they have not been able to causally demonstrate the nature of the cognitive processes by which this occurs in real-time. Electrical brain stimulation is able to demonstrate causal links between a brain region and a given function with high temporal precision. By examining behavior in a memory task as subjects received MTL stimulation, we provide the first causal evidence demonstrating the role of the MTL in organizing the spatial and temporal aspects of episodic memory.


Subject(s)
Entorhinal Cortex/physiology , Hippocampus/physiology , Memory/physiology , Spatial Memory/physiology , Time Perception/physiology , Brain Mapping , Computer Simulation , Electric Stimulation , Electrodes, Implanted , Epilepsy/surgery , Female , Humans , Magnetic Resonance Imaging , Male , Memory, Episodic , Mental Recall/physiology , Temporal Lobe/physiology
15.
Diabetes Obes Metab ; 21(2): 393-396, 2019 02.
Article in English | MEDLINE | ID: mdl-30136353

ABSTRACT

The 1245.29 Trial recently showed that empaglifozin improved both blood pressure and glucose control in African American (AA) patients with type 2 diabetes (T2D) and hypertension. Using the Diabetes Collaborative Registry, a large-scale US registry of outpatients with diabetes recruited from primary care, cardiology and endocrinology practices, we sought to understand the potential impact of these observations in routine clinical practice. Among 74 290 AA patients with T2D from 368 US clinics, 60.4% had hypertension, of whom 34.5% had systolic blood pressure ≥ 140 mm Hg (20.8% of the total AA T2D population). Only 1.7% of this eligible population had been prescribed a sodium-glucose co-transporter two inhibitor. The mean estimated 5-year risk of cardiovascular death was 7.7%, which could be reduced to 6.2% when modelling the antihypertensive effect of empagliflozin across the eligible population (based on an 8-mm Hg blood pressure reduction). These findings may represent a potential opportunity for better management of cardiovascular risk factors and improved outcomes in this vulnerable cohort.


Subject(s)
Benzhydryl Compounds/therapeutic use , Black or African American , Diabetes Mellitus, Type 2/drug therapy , Glucosides/therapeutic use , Hypertension/drug therapy , Practice Patterns, Physicians'/statistics & numerical data , Black or African American/statistics & numerical data , Aged , Blood Pressure/drug effects , Blood Pressure Determination , Diabetes Complications/drug therapy , Diabetes Complications/ethnology , Diabetes Mellitus, Type 2/complications , Diabetes Mellitus, Type 2/physiopathology , Female , Humans , Hypertension/complications , Hypertension/ethnology , Intersectoral Collaboration , Male , Middle Aged , Multicenter Studies as Topic , Randomized Controlled Trials as Topic , Registries , Translational Research, Biomedical , Treatment Outcome , United States/epidemiology
16.
Am Heart J ; 206: 131-133, 2018 12.
Article in English | MEDLINE | ID: mdl-30528916

ABSTRACT

Contemporary utilization patterns for targeted temperature management (TTM) among patients with acute myocardial infarction (MI) and out-of-hospital cardiac arrest (OHCA) have not been well characterized in the United States. In this nationwide evaluation of MI patients with OHCA (01/2015-03/2016; 691 hospitals), 34.1% (1792/5260) of OHCA patients received TTM. Patients who were treated with TTM had higher risk clinical features. A wide inter-hospital variation (ranging from 0% to 82%) in TTM use observed despite few differences in case mix.


Subject(s)
Cardiopulmonary Resuscitation/methods , Hypothermia, Induced/methods , Myocardial Infarction/therapy , Out-of-Hospital Cardiac Arrest/therapy , Registries , Female , Humans , Male , Middle Aged , Myocardial Infarction/complications , Out-of-Hospital Cardiac Arrest/etiology , United States
17.
Am Heart J ; 203: 25-29, 2018 09.
Article in English | MEDLINE | ID: mdl-30015065

ABSTRACT

BACKGROUND: Optimal glucose-lowering strategies in patients with both heart failure (HF) and type 2 diabetes mellitus (T2D) are not well defined, particularly as novel medication classes emerge.We sought to evaluate current patterns of glucose-lowering medication use in adults with T2D with and without HF. METHODS: The DCR is a US-based outpatient registry of adults with diabetes; currently includes 3074 providers in 203 practices. We used hierarchical, modified Poisson regression models to examine the relationship between concomitant HF with use of each glucose-lowering medication class, adjusting for other factors that could impact selection of one medication class over another: age, chronic kidney disease (CKD), coronary artery disease (CAD), number of glucose-lowering medications, and insurance. RESULTS: Among 456,106 adults with T2D, 125,161 (27%) had a diagnosis of HF (30% HFrEF, 15%HFmrEF, 55% HFpEF). Patients with T2D and HF were more likely to be older and male, and to have CAD, atrial fibrillation, and CKD. In the multivariable models, HF was associated with a greater use of insulin (RR 1.39, 95% CI 1.36-1.42) and lower use of thiazolidinediones (RR 0.79, 95% CI 0.74-0.83), SGLT2 inhibitors (RR 0.83, 95% CI 0.79-0.89), and metformin (RR 0.84, 95% CI 0.82-0.86). Among the subgroup of patients with HF, thiazolidinediones, GLP-1 receptor agonists, and SGLT2 inhibitors were used even less often in patients with lower ejection fraction, indicating that both the diagnosis of clinical HF and ejection fraction may influence the choice of glucose-lowering medications. CONCLUSION: In a large US-based outpatient registry, we found that a quarter of adults with T2D had a diagnosis of HF, which was predominantly HFpEF. Although certain T2D medication use in patients with HF appeared consistent with evidence (less use of thiazolidinediones), others appeared contrary to evidence (less use of metformin and SGLT2 inhibitors).


Subject(s)
Blood Glucose/metabolism , Diabetes Mellitus, Type 2/drug therapy , Heart Failure/drug therapy , Hypoglycemic Agents/therapeutic use , Registries , Aged , Diabetes Mellitus, Type 2/blood , Diabetes Mellitus, Type 2/complications , Female , Follow-Up Studies , Heart Failure/blood , Heart Failure/complications , Humans , Male , Outpatients/statistics & numerical data , Retrospective Studies , Treatment Outcome
18.
Crit Care Med ; 46(8): 1230-1237, 2018 08.
Article in English | MEDLINE | ID: mdl-29727364

ABSTRACT

OBJECTIVES: Patients requiring mechanical ventilation have high morbidity and mortality. Providing palliative care services has been suggested as a way to improve comprehensive management of critically ill patients. We examined the trend in the utilization of palliative care among adults who require prolonged mechanical ventilation. Primary objectives were to determine the trend in palliative care utilization over time, predictors for palliative care utilization, and palliative care impact on hospital length of stay. DESIGN: Retrospective, cross-sectional study. SETTING: The National Inpatient Sample data between 2009 and 2013 was used for this study. PATIENTS: Adults (age ≥ 18 yr) who underwent prolonged mechanical ventilation (≥ 96 consecutive hr) were studied. MEASUREMENTS AND MAIN RESULTS: Palliative care and mechanical ventilation were identified using the corresponding International Classification of Diseases, 9th revision, Clinical Modification, codes. A total of 1,751,870 hospitalizations with prolonged mechanical ventilation were identified between 2009 and 2013. The utilization of palliative care increased yearly from 6.5% in 2009 to 13.1% in 2013 (p < 0.001). Among the mechanically ventilated patients who died, palliative care increased from 15.9% in 2009 to 33.3% in 2013 (p < 0.001). Median hospital length of stay for patients with and without palliative care was 13 and 17 days, respectively (p < 0.001). Patients discharged to either short- or long-term care facilities had a shorter length of stay if palliative care was provided (15 vs 19 d; p < 0.001). The factors associated with a higher palliative care utilization included older age, malignancy, larger hospitals in urban areas, and teaching hospitals. Non-Caucasian race was associated with lower palliative care utilization. CONCLUSIONS: Among patients who undergo prolonged mechanical ventilation, palliative care utilization is increasing, particularly in patients who die during hospitalization. Using palliative care for mechanically ventilated patients who are discharged to either short- or long-term care facilities is associated with a shorter hospital length of stay.


Subject(s)
Critical Illness/mortality , Palliative Care/trends , Respiration, Artificial/mortality , Age Factors , Aged , Aged, 80 and over , Cross-Sectional Studies , Female , Humans , Length of Stay/statistics & numerical data , Male , Middle Aged , Residence Characteristics/statistics & numerical data , Retrospective Studies , Socioeconomic Factors , Time Factors , United States/epidemiology
19.
J Nucl Cardiol ; 24(6): 1966-1975, 2017 12.
Article in English | MEDLINE | ID: mdl-27659457

ABSTRACT

BACKGROUND: A drop in blood pressure (BP) or blunted BP response is an established high-risk marker during exercise myocardial perfusion imaging (MPI); however, data are sparse regarding the prognostic value of BP response in patients undergoing vasodilator stress rubidium-82 (Rb-82) Positron Emission Tomography (PET) MPI. METHODS AND RESULTS: From the PET Prognosis Multicenter Registry, a cohort of 3413 patients underwent vasodilator stress Rb-82 PET MPI with dipyridamole or adenosine. We used multivariable Cox proportional hazard regression to analyze the association with mortality of four BP variables: stress minus rest systolic BP (∆SBP), stress minus rest diastolic BP (∆DBP), resting systolic BP (rSBP), and resting diastolic BP (rDBP). Covariates that had univariate P values <.10 were entered into the multivariable model. After median 1.7 years follow-up, 270 patients died. In univariate analyses, ∆SBP (P = .082), rSBP (P = .008), and rDBP (P < .001) were of potential prognostic value (P < .10), but ∆DBP was not (P = .96). After adjustment for other clinical and MPI variables, ∆SBP no longer independently predicted mortality (P = .082); only lower rSBP (P = .026) and lower rDBP (P = .045) remained independently prognostic. CONCLUSIONS: In patients undergoing vasodilator stress MPI, only lower resting BP is an independent predictor of mortality along with other clinical and MPI variables; BP response does not appear to add to risk stratification in these patients.


Subject(s)
Blood Pressure/drug effects , Myocardial Perfusion Imaging/methods , Positron-Emission Tomography/methods , Rubidium Radioisotopes , Vasodilator Agents/pharmacology , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Prognosis , Proportional Hazards Models , Registries
20.
Europace ; 19(12): 1994-2000, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28065887

ABSTRACT

AIMS: End-stage renal disease (ESRD) increases the risk of implantable cardioverter-defibrillator (ICD) infection. We sought to define outcomes of lead extraction in patients with ESRD. METHODS AND RESULTS: Implantable cardioverter-defibrillator lead extractions at our institution from January 2006 to March 2014 were stratified by absence (Control-Ex, n = 465) or presence (ESRD-Ex, n = 43) of ESRD. Procedural outcomes and survival were determined by medical records review. Survival in the ESRD-Ex group was compared with a contemporaneous cohort with ESRD undergoing ICD lead implantation (ESRD-I, n = 127). Among extraction patients, those with ESRD were more likely to be extracted for infection (74.4% vs. 28.6%, P < 0.001). Extraction procedure success (Control-Ex: 97% vs. ESRD-Ex: 93%, P = 0.17) and procedural deaths (Control-Ex: 1.1% vs. ESRD-Ex: 2.3%, P = 0.413) were similar. Survival 1 year following extraction was worse in the ESRD-Ex group compared with the Control-Ex, with a survival rate of 65.6% vs. 92.6% (P < 0.001); these curves continued to diverge through year 3. One-year survival in the ESRD-Ex group was worse than among ESRD patients undergoing ICD implant (ESRD-I), but these curves converged and survival was similar by year 3. CONCLUSIONS: Implantable cardioverter-defibrillator lead extraction can be performed safely and effectively in patients with ESRD. However, despite high rates of procedural success, long-term mortality following extraction in ESRD patients is substantial. Much of the long-term mortality risk appears to be accounted for by the presence of ESRD and an indication for an ICD.


Subject(s)
Defibrillators, Implantable/adverse effects , Device Removal/methods , Electric Countershock/adverse effects , Electric Countershock/instrumentation , Kidney Failure, Chronic/complications , Prosthesis Failure , Prosthesis-Related Infections/surgery , Adult , Aged , Device Removal/adverse effects , Device Removal/mortality , Electric Countershock/mortality , Female , Georgia , Humans , Kaplan-Meier Estimate , Kidney Failure, Chronic/diagnosis , Kidney Failure, Chronic/mortality , Male , Middle Aged , Prosthesis-Related Infections/diagnosis , Prosthesis-Related Infections/mortality , Retrospective Studies , Risk Assessment , Risk Factors , Time Factors , Treatment Outcome
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