bluuebunny/crossref_metadata_2025_split huggingface dataset:
Presence of human herpes virus 6 DNA exclusively in temporal lobe epilepsy brain tissue of patients with history of encephalitis
Authors: Niehusmann Pitt , Mittelstaedt Tobias , Bien Christian G. , Drexler Jan F. , Grote Alexander , Schoch Susanne , Becker Albert J. 
Published: October 2010

SummaryTemporal lobe epilepsy (TLE) is frequently associated with mesial temporal sclerosis (MTS). Many etiologic aspects of TLE are still unresolved. Here, we aimed to analyze the presence of human herpes virus 6 (HHV‐6) DNA in distinct TLE pathologies. Nested polymerase chain reaction (PCR) in surgical tissue from 38 pharmacoresistant TLE patients and 10 autopsy controls revealed HHV‐6 DNA in 55.6% of the TLE patients with a history of encephalitis, involving MTS and gliotic hippocampi without substantial neurodegeneration, but not in lesion‐associated TLE or nonlesional MTS with or without a history of complex febrile seizures (CFS). HHV‐6 protein was present in only one patient’s tissue. Our data argue against HHV‐6 as a major local pathogenetic factor in MTS hippocampi after CFS. The high detection rate of HHV‐6 DNA suggests a potential pathogenetic role of HHV‐6 in TLE patients with a history of encephalitis.
Spontaneous and evoked high‐frequency oscillations in the tetanus toxin model of epilepsy
Authors: Rolston John D. , Laxpati Nealen G. , Gutekunst Claire‐Anne , Potter Steve M. , Gross Robert E. 
Published: October 2010

SummaryPurpose:  High‐frequency oscillations (HFOs) are an emerging biomarker for epileptic tissue. Yet the mechanism by which HFOs are produced is unknown, and their rarity makes them difficult to study. Our objective was to examine the occurrence of HFOs in relation to action potentials (APs) and the effect of microstimulation in the tetanus toxin (TT) model of epilepsy, a nonlesional model with a short latency to spontaneous seizures.Methods:  Rats were injected with TT into dorsal hippocampus and implanted with a 16‐channel (8 × 2) multielectrode array, one row each in CA3 and CA1. After onset of spontaneous seizures (3–9 days), recordings were begun of APs and local field potentials, analyzed for the occurrence of interictal spikes and HFOs. Recordings were made during microstimulation of each electrode using customized, open‐source software.Results:  Population bursts of APs during interictal spikes were phase‐locked with HFOs, which were observable almost exclusively with high‐amplitude interictal spikes. Furthermore, HFOs could reliably be produced by microstimulation of the hippocampus, providing evidence that these oscillations can be controlled temporally by external means.Discussion:  We show for the first time the occurrence of HFOs in the TT epilepsy model, an attractive preparation for their experimental investigation and, importantly, one with a different etiology than that of status models, providing further evidence of the generality of HFOs. The ability to provoke HFOs with microstimulation may prove useful for better understanding of HFOs by directly evoking them in the lab, and designing high‐throughput techniques for presurgical localization of the epileptic focus.
Pubertal Development, Sleep Problems, and Alcohol Use: A Commentary
Authors: Wong Maria M. 
Published: October 2010

Background:  This commentary discussed the study conducted by Pieters et al. (2010 Alcohol Clin Exp Res in press) on the relationships among puberty dependent, sleep regulation, and alcohol use in adolescents. The goal of this commentary is to underscore the significance of the study and discuss some of the unaddressed questions in the area.Methods:  The significance of the study and unaddressed questions are discussed.Results:  Pieters et al. (2010 Alcohol Clin Exp Res in press) provided valuable data to understanding the relationships among puberty, sleep problems, and alcohol use. Questions regarding the relationship between puberty and sleep problems, the possible reciprocal relationships among circadian phase preference, sleep problems and alcohol use, mediators and moderators of such relationships, as well as potential gender differences on these relationships were discussed.Conclusions:  To understand the relationships among pubertal development, sleep problems, and alcohol use, researchers need to be aware of the physiological changes that take place in puberty, as well as the psychosocial factors that are associated with such changes. Important mediators and moderators of the relationships among these constructs also need to be identified. Longitudinal design may be useful in this regard.
Pregnenolone and Ganaxolone Reduce Operant Ethanol Self‐Administration in Alcohol‐Preferring P Rats
Authors: Besheer Joyce , Lindsay Tessa G. , O’Buckley Todd K. , Hodge Clyde W. , Morrow A. Leslie 
Published: October 2010

Background: Neuroactive steroids modulate ethanol intake in several self‐administration models with variable effects. The purpose of this work was to examine the effects of the long‐acting synthetic GABAergic neurosteroid ganaxolone and the endogenous neurosteroid pregnenolone, a precursor of all GABAergic neuroactive steroids, on the maintenance of ethanol self‐administration in an animal model of elevated drinking—the alcohol‐preferring (P) rats.Methods: P rats were trained to self‐administer ethanol (15% v/v) versus water on a concurrent schedule of reinforcement, and the effects of ganaxolone (0 to 30 mg/kg, subcutaneous [SC]) and pregnenolone (0 to 75 mg/kg, intraperitoneal [IP]) were evaluated on the maintenance of ethanol self‐administration. After completion of self‐administration testing, doses of the neuroactive steroids that altered ethanol self‐administration were assessed on spontaneous locomotor activity. Finally, the effect of pregnenolone administration on cerebral cortical levels of the GABAergic neuroactive steroid (3α,5α)‐3‐hydroxypregnan‐20‐one (allopregnanolone, 3α,5α‐THP) was determined in both ethanol‐experienced and ethanol‐inexperienced P rats because pregnenolone is a precursor of these steroids.Results: Ganaxolone produced a dose‐dependent biphasic effect on ethanol reinforcement, as the lowest dose (1 mg/kg) increased and the highest dose (30 mg/kg) decreased ethanol‐reinforced responding. However, the highest ganaxolone dose also produced a nonspecific reduction in locomotor activity. Pregnenolone treatment significantly reduced ethanol self‐administration (50 and 75 mg/kg), without altering locomotor activity. Pregnenolone (50 mg/kg) produced a significant increase in cerebral cortical allopregnanolone levels. This increase was observed in the self‐administration trained animals, but not in ethanol‐naïve P rats.Conclusions: These results indicate that pregnenolone dose‐dependently reduces operant ethanol self‐administration in P rats without locomotor impairment, suggesting that it may have potential as a novel therapeutic for reducing chronic alcohol drinking in individuals that abuse alcohol.
The Nicotinic Acetylcholine Receptor Partial Agonist Varenicline Increases the Ataxic and Sedative‐Hypnotic Effects of Acute Ethanol Administration in C57BL/6J Mice
Authors: Kamens Helen M. , Andersen Jimena , Picciotto Marina R. 
Published: October 2010

Background: The costs associated with alcohol abuse are staggering, therefore much effort has been put into developing new pharmacologic strategies to decrease alcohol abuse. Recently, the nicotinic acetylcholine receptor (nAChR) partial agonist varenicline has been shown to decrease ethanol consumption in both humans and animal models.Methods: We examined the effects of varenicline on the ataxic and sedative‐hypnotic effects of ethanol. First, varenicline was administered prior to placement in a locomotor activity chamber to determine whether varenicline influenced baseline locomotor activity. To determine the effect of nicotinic modulation on ethanol‐induced motor incoordination, varenicline was administered 30 minutes prior to an acute ethanol injection and then mice were tested on the balance beam, dowel test, or fixed‐speed rotarod. To examine ethanol’s sedative‐hypnotic effects, varenicline was administered 30 minutes prior to 4 g/kg ethanol and the duration of loss of righting reflex (LORR) was measured.Results: Varenicline markedly reduced baseline locomotor activity in C57BL/6J mice. Varenicline increased ethanol‐induced ataxia when measured on the balance beam and dowel test but had no effect when measured on the fixed‐speed rotarod. Pretreatment with varenicline increased the duration of LORR.Conclusions: These data provide evidence that nAChRs may be involved in the ataxic and sedative effects of ethanol. It is possible that one mechanism that could contribute to the ability of varenicline to decrease ethanol consumption may be through increasing negative behavioral effects of alcohol.
Emotional Distress in Partners of Patients with an Implantable Cardioverter Defibrillator: A Systematic Review and Recommendations for Future Research
Authors: VAN DEN BROEK KRISTA C. , HABIBOVIĆ MIRELA , PEDERSEN SUSANNE S. 
Published: October 2010

Both patients with an implantable cardioverter defibrillator (ICD) and their partners face challenges when adapting to the ICD. Distress is a burden on its own for partners but may also affect well being and health of patients. This review provides a systematic overview of the literature on psychological distress in partners of ICD patients and recommendations for future research. PubMed and PsycInfo were searched in March 2010 using a priori defined search terms. This search and the additional hand search resulted in 22 studies, of which 13 were quantitative and eight qualitative. Sample sizes in quantitative studies varied considerably from 10 to 196 partners, with only six of 13 studies including >50 partners. Partner levels of distress were at least on par with patient levels. The majority of large‐scale studies suggested that partner distress levels decrease in the first year postimplantation. Most studies reported no impact of ICD shocks on distress levels or quality of life in partners. ICD indication as well as comorbid conditions, age, and the psychological profile of the partner were related to distress and quality of life. Domains of concern emerging from qualitative studies were related to care of the ICD patient, helplessness and uncertainties related to shocks, role changes, sexual activities, overprotectiveness, and driving. Partner levels of distress may be as high as that of ICD patients. Research with large samples is needed to further investigate the course and determinants of partner distress and the influence that partner distress may have on patient health outcomes. (PACE 2010; 33:1442–1450)
Spironolactone Therapy is Associated with Reduced Ventricular Tachycardia Rate in Patients with Cardiomyopathy
Authors: DIMAS VASSILIS , AYERS COLBY , DANIELS JAMES , JOGLAR JOSE A. , HILL JOSEPH A. , NASEEM R. HARIS 
Published: October 2010

Introduction: Multiple pharmacological therapies currently in prevalent clinical use for cardiac diseases have antifibrotic properties. Spironolactone, a potent antifibrotic agent, is currently used for advanced heart failure. Therapies such as HMG‐CoA reductase inhibitors (statins) and angiotensin‐converting enzyme inhibitors (ACEi) also have antifibrotic properties. However, the effect of these medications on the ventricular arrhythmia phenotype is currently unknown. Therefore, we set out to define the ventricular arrhythmia rates in patients actively treated with such therapies.
Methods and Results: We retrospectively evaluated the ventricular tachycardia (VT) rates in patients with structural heart disease actively treated with therapies with antifibrotic properties. VT rates were significantly diminished in patients treated with spironolactone (158 ± 26 beats per minute [bpm], n = 21) compared to patients on no medications (205 ± 22 bpm, n = 13) or those who were on similar heart‐failure therapies but not on spironolactone (186 ± 32 bpm, n = 82). In addition, we observed that VT rates showed a significant trend toward lower rates in patients receiving either statins or ACEi, compared to patients on no medical therapy. In multivariate analysis, spironolactone therapy was identified as the single most significant variable for reduced VT rate.
Conclusion: Use of spironolactone in patients with heart failure is associated with reduced VT rate. Similar but less‐significant reductions in VT rates were observed with use of other pharmacological agents with antifibrotic properties, such as statins and ACEi. Our findings, at least in part, could account for reduction in sudden cardiac death rates documented with use of these therapies. (PACE 2011; 34:309–314))
Increased Heterogenity of Ventricular Repolarization in Obese Nonhypertensive Children
Authors: NIGRO GERARDO , RUSSO VINCENZO , DI SALVO GIOVANNI , DE CRESCENZO ILARIA , RAGO ANNA , PERRONE LAURA , GOLINO PAOLO , RUSSO MARIA GIOVANNA , CALABRÒ RAFFAELE 
Published: October 2010

Objective: Obese children, without arterial hypertension, may be a unique clinical opportunity to evaluate the effect of obesity, per se, on ventricular repolarization, excluding the influence of possible comorbidities. The QTc dispersion (QTc‐d), JTc dispersion (JTc‐d), and transmural dispersion of repolarization (TDR) have been suggested to be electrocardiographic indexes reflecting the physiological variability of regional ventricular repolarization. The aim of our study is to define the effects of obesity on the ventricular repolarization in obese children who have no other clinically appreciable cause of heart disease.
Methods: The study involved 70 subjects (48 male, 22 female), with a mean age (± standard deviation) of 13 ± 2 years. A total of 35 individuals were obese (Group A: 24 male, 11 female, mean body mass index [BMI] of 38.2 ± 5.8 kg/m2), and 35 participants were healthy lean children (Group C: 24 male, 11 female, mean BMI of 22.3 ± 0.3 kg/m2). Heart rate; QRS duration; maximum and minimum QT interval; and QTc‐d, JTc‐d, and TDR measurement were performed.
Results: Compared with the healthy control group, obese children presented increased values of the QTc‐d, JTc‐d, and TDR (31.1 ± 10.6 vs 46.2 ± 15.3 ms, P < 0.003; 29.8 ± 8.5 vs 40.1 ± 10.3 ms, P < 0.04; 83.2 ± 13.5 vs 100.7 ± 16.3 ms, P < 0.05). A statistically significant correlation was found between the values of QTc‐d, insulin serum concentration (r = 0.46, P = 0.04), and homeostasis model assessment of insulin resistance (r = 0.34, P = 0.03).
Conclusions: Our data suggest that obese nonhypertensive children have an increased ventricular repolarization heterogeneity in relation to controls. (PACE 2010; 33:1533–1539)
Trends of Temporary Pacemaker Implant and Underlying Disease Substrate
Authors: JOU YU‐LAN , HSU HONG‐PIN , TUAN TA‐CHUAN , WANG KANG‐LING , LIN YENN‐JIANG , LO LI‐WEI , HU YU‐FENG , KONG CHI‐WOON , CHANG SHIH‐LIN , CHEN SHIH‐ANN 
Published: October 2010

Background: To evaluate contemporary trends of clinical characteristics, etiologies, and underlying diseases, and their relationship between different bradyarrhythmias in patients undergoing temporary pacemakers (TPMs).
Methods: This study included 509 patients (77 ± 11 year, 74% males) with symptomatic bradyarrhythmias requiring TPMs between 2002 and 2008. Demographics, electrocardiographic indications, etiologies, underlying diseases, and the outcome of permanent pacemaker (PPM) implants within 30 days were analyzed.
Results: Atrioventricular conduction dysfunction (AVCD) (64.0%) dominated in all bradyarrhythmias, with idiopathic degeneration (61%) as its major etiology. Antiarrhythmic drug (38%) was the leading cause in sinoatrial node dysfunction (SAND). There was an increasing trend in AVCD, while a decreasing trend in SAND. Regarding etiologies for TPM, an increasing trend was found in idiopathic degeneration, whereas a decreasing trend in acute coronary syndrome (ACS). Idiopathic degeneration had an odds ratio (OR) of 1.9 for AVCD (P = 0.001), whereas electrolyte/acid‐base disturbances (OR = 3.7, P = 0.001), β‐blockers (OR = 2.4, P = 0.002), and chronic renal disease (OR = 1.9, P = 0.01) were associated with SAND. Patients with intrinsic etiologies for TPM had a high incidence of PPM implantation within 30 days than those with extrinsic causes (67.5% vs 3.8%, P < 0.0001)
Conclusion: Increasing trends in patients requiring TPMs were observed in the elderly patients and those with AVCD and idiopathic degeneration, while decreasing trends were observed in those with SAND and ACS. Idiopathic degeneration was associated with AVCD, whereas extrinsic etiologies were related to SAND. Patients with intrinsic etiologies had a higher incidence of PPM implantation than those with extrinsic factors for TPM. (PACE 2010; 33:1475–1484)
Predictors of Mortality in Patients with Chagas’ Cardiomyopathy and Ventricular Tachycardia Not Treated with Implantable Cardioverter‐Defibrillators
Authors: SARABANDA ALVARO VALENTIM LIMA , MARIN‐NETO JOSÉ ANTÔNIO 
Published: October 2010

Background: The natural history of the arrhythmogenic form of Chagas’ heart disease is not fully understood.
Methods: We assessed the outcome of 56 patients with Chagas’ cardiomyopathy ([31 men]; mean age of 55 years; mean left ventricular ejection fraction [LVEF] 42%) presenting with either sustained ventricular tachycardia (VT) or nonsustained VT (NSVT), before therapy with implantable cardioverter‐defibrillator was available at our center.
Results: Over a mean follow‐up of 38 ± 16 months (range, 1–61 months), 16 patients (29%) died, 11 due to sudden cardiac death (SCD), and five from progressive heart failure. Survivors and nonsurvivors had comparable baseline characteristics, except for a lower LVEF (46 ± 7% vs 31 ± 9%, P < 0.001) and a higher New York Heart Association class (P = 0.003) in those who died during follow‐up. Receiver‐operator characteristic curve analysis showed that an LVEF cutoff value of 38% had the best accuracy for predicting all‐cause mortality and an LVEF cutoff value of 40% had the best accuracy for prediction of SCD. Using the multivariate Cox regression analysis, LVEF < 40% was the only predictor of all‐cause mortality (hazard ratio [HR] 12.22, 95% confidence interval [CI] 3.46–43.17, P = 0.0001) and SCD (HR 6.58, 95% CI 1.74–24.88, P = 0.005).
Conclusions: Patients with Chagas’ cardiomyopathy presenting with either sustained VT or NSVT run a major risk for mortality when had concomitant severe or even moderate LV systolic dysfunction. (PACE 2011; 54–62)
Clinical Predictors of Conduction Disease Progression in Type I Myotonic Muscular Dystrophy
Authors: NAZARIAN SAMAN , WAGNER KATHRYN R. , CAFFO BRIAN S. , TOMASELLI GORDON F. 
Published: October 2010

Background: Patients with type I myotonic muscular dystrophy (DM1) are at risk for sudden death due to atrioventricular conduction block. We sought to characterize the trends and predictors of time‐dependent electrocardiographic (ECG) variations in patients with DM1.
Methods: Seventy patients with DM1 underwent standard electrocardiography at first evaluation and routine and symptom prompted follow‐up. Individual variations in ECG conduction intervals were assessed using spaghetti plots. Clinical predictors of conduction disease progression were assessed using multivariate random effects regression models of panel data clustered by patient and adjusted for heart rate.
Results: Substantial individual variability was noted in time‐dependent changes in PR, QRS, and QTc intervals of patients with DM1
. Changes in the QTc interval were closely associated with prolongation of the QRS interval. Age, the presence of paroxysmal atrial flutter or fibrillation, and the number of cytosine‐thymine‐guanine (CTG) repeats were independent positive predictors of time‐dependent PR and QRS prolongation during long‐term follow‐up. Female sex was negatively associated with PR prolongation but positively associated with QTc prolongation. Lower left ventricular ejection fraction was associated with greater QRS interval progression during long‐term follow‐up but was not predictive of PR interval progression.
Conclusions: Patients with DM1 can develop rapid changes in cardiac conduction intervals. Paroxysmal atrial flutter or fibrillation, older age, and larger CTG expansions predict greater time‐dependent PR and QRS interval prolongation and warrant particular attention in the arrhythmic evaluation of this high risk patient subset. (PACE 2011; 34:171–176)
Effect of Substance Abuse on Defibrillation Threshold in Patients with Implantable Cardioverter‐Defibrillator
Authors: PERRINE SHANE A. , NAYAK RAGHAVENDRA , BHARADWAJ ADITYA S. , MCKELVEY GEORGE , MOHAMAD TAMAM , JACOB SONY 
Published: October 2010

Background:
The use of recreational drugs has been observed to have deleterious effects on the heart. The aim of our study was to evaluate the effect of substance abuse on the defibrillation threshold (DFT) in patients with implantable cardioverter‐defibrillators (ICDs).
Methods:
A retrospective analysis was conducted on patients who had undergone ICD placement at a tertiary university medical center in Detroit, Michigan. Subjects were identified based on self‐reported drug use and placed into one of the three groups: controls, cocaine, and other illicit drugs. Due to a disparity in race among groups, the main analysis on DFT value was conducted on African‐American patients only. Furthermore, exploratory analyses were conducted to investigate the effects of marijuana use and race on DFT values.
Results:
A history of cocaine use (n = 17) significantly increases DFT among African Americans (17.3 ± 8 Joule [J] vs 12.5 ± 5 J in cases vs controls, P < 0.05), while previous use of marijuana does not significantly influence DFT. African‐American patients with a history of illicit drug use had indications for ICD implantation at an earlier age and that within the control (nondrug using) group; African Americans (n = 73) had higher DFT compared to Caucasians (n = 32), (14.5 ± 0.5 J vs 9.7 ± 0.6 J, P < 0.05).
Conclusions:
A history of cocaine use in African Americans with ICD is a risk factor for high DFT and race itself (being African American) may be a risk for high DFT. Use of high‐energy ICDs and other DFT lowering techniques may be considered for patients who have used or continue to use cocaine or in whom DFT testing cannot be performed at the time of implantation. (PACE 2011; 34:193–199)