bluuebunny/crossref_metadata_2025_split huggingface dataset:
Serious psychological distress among persons with epilepsy based on the 2005 California Health Interview Survey
Authors: Layne Moore J. , Elliott John O. , Lu Bo , Klatte Emily T. , Charyton Christine 
Published: February 2009

SummaryPurpose:  To compare the prevalence of self‐reported serious psychological distress using the Kessler 6 (K6) in persons with a history of epilepsy (PWE) to those without epilepsy from a population‐based survey.Methods:  Data were analyzed from adults aged ≥18 years (n = 43,020) who participated in the 2005 California Health Interview Survey (CHIS).Results:  California adults with a history of epilepsy, after controlling for demographics and comorbidities, reported higher rates of feeling nervous [odds ratio (OR) 2.22], feeling hopeless (OR 1.35), feeling restless (OR 2.07), feeling depressed (OR 3.14), and feeling worthless (OR 2.57), and reported that everything has been an effort (OR 2.28) in the last 30 days. The K6 score showed that serious psychological distress is more common in PWE (OR 2.24). After adjusting for demographics, comorbidities, and serious psychological distress, PWE are more likely to report having 14 or more physical, mental, and general unhealthy days in the last 30 days.Discussion:  PWE have significantly higher rates of serious psychological distress and poor health‐related quality of life after controlling for demographics, comorbidities. These comorbid conditions need to be factored into any comprehensive treatment strategy for managing PWE to achieve optimum quality of life.
Excellent Long‐Term Reproducibility of the Electrophysiologic Efficacy of Quinidine in Patients with Idiopathic Ventricular Fibrillation and Brugada Syndrome
Authors: BELHASSEN BERNARD , GLICK AHARON , VISKIN SAMI 
Published: February 2009

Background: Quinidine is very effective in preventing the reinduction of sustained ventricular fibrillation (VF) during electrophysiologic study (EPS) in patients with idiopathic VF and Brugada syndrome. However, there are no data on the long‐term reproducibility of this EP efficacy.
Methods and Results: Nine patients (seven males and two females, aged 21–72 years), who suffered from aborted cardiac arrest (n = 8) or recurrent syncope (n = 1) due to Brugada syndrome (n = 5) or idiopathic VF (n = 4), comprised the study. All patients had inducible sustained VF at baseline that was prevented by quinidine therapy and underwent another EPS on medication after 1.7–23.6 (9.8 ± 6.8) years (>5 years in eight patients). Two patients underwent two late EPS on quinidine. The goal of repeat EPS on quinidine was to ensure persistent long‐term drug efficacy (n = 6) or to elucidate the reason of syncopal episodes during therapy (n = 3). The EPS protocol significantly evolved over the years as it became more aggressive (more pacing sites and/or more ventricular extrastimuli). All nine patients tolerated the medication well and had no recurrent documented arrhythmic events during long‐term follow‐up (mean 15 ± 7 years). No sustained ventricular tachyarrhythmias could be induced in any patient during repeat late EPS. In six patients, a more aggressive stimulation protocol could be tested at repeat EPS.
Conclusion: The long‐term reproducibility of the EP efficacy of quinidine in patients with idiopathic VF and Brugada syndrome is excellent. EP‐guided quinidine therapy represents a valuable long‐term alternative to ICD therapy in these patients.
Noninvasive Evidence of Shortened Atrial Refractoriness during Sinus Rhythm in Patients with Paroxysmal Atrial Fibrillation
Authors: HOLMQVIST FREDRIK , CARLSON JONAS , WAKTARE JOHAN E.P. , PLATONOV PYOTR G. 
Published: February 2009

Background: Shortening of the atrial refractory period is the key feature of atrial electrical remodeling during atrial fibrillation (AF). During sinus rhythm (SR), assessment of the atrial refractoriness is hampered by the fact that the atrial repolarization wave (Ta wave) is largely obscured by the following QRST complex. The purpose of this study was to study the Ta wave in subjects with paroxysmal AF during SR with third‐degree atrioventricular (AV) block, and in matched controls.
Methods: Fifteen patients (mean age 70 ± 10 years, five males) with paroxysmal AF undergoing AV‐nodal ablation were studied. Fifteen age‐ and gender‐matched subjects (mean age 71 ± 9 years, five males) with third‐degree AV block, without a history of heart disease, were used as controls. Standard 12‐lead electrocardiograms (ECGs) were recorded and transformed to orthogonal leads and studied using P‐wave signal averaging technique.
Results: The P to Ta interval was shorter (408 ± 47 ms vs 451 ± 53 ms, P = 0.017) and in Lead Y the Ta peak location was earlier (156 ± 31 ms vs 187 ± 34 ms, P = 0.002) in subjects with paroxysmal AF than in the controls. The P‐wave duration (126 ± 15 ms vs 129 ± 17 ms, P = 0.59) and morphology was similar in AF patients and controls.
Conclusions: In this study, the ECG signs of shorter atrial refractoriness associated with a history of AF are visualized for the first time during SR. The finding of the earlier location of the PTa peak in AF subjects implies that a possible indicator of increased arrhythmia susceptibility may be visible already in the unprocessed ECG.
The Characteristics and Distribution of the Scar Tissue Predict Ventricular Tachycardia in Patients with Advanced Heart Failure
Authors: YOKOKAWA MIKI , TADA HIROSHI , KOYAMA KEIKO , INO TOSHIHIKO , HIRAMATSU SHIGEKI , KASENO KENICHI , NAITO SHIGETO , OSHIMA SHIGERU , TANIGUCHI KOICHI 
Published: February 2009

Background: Contrast‐enhanced magnetic resonance imaging (CMR) identifies scar tissue as hyperenhanced areas. We sought to clarify the relationship between the scar characteristics and occurrence of sustained ventricular tachycardia (VT) in patients with advanced heart failure.
Methods: CMR was performed in 29 patients with dilated cardiomyopathy (DCM group) and 18 patients with ischemic cardiomyopathy (ICM group). The characteristics, volume, and distribution of the hyperenhanced areas were analyzed by CMR. The CMR parameters and clinical arrhythmic events were compared between the two groups.
Results: In the DCM group, almost all hyperenhanced areas were nontransmural, and presented frequently in the midwall layer. The volume of the hyperenhanced areas and total number of hyperenhanced segments were greater in patients with sustained VT than in those without. On the other hand, in the ICM group, transmural or subendocardial hyperenhanced areas were detected in the territory of the coronary arteries. The volume of the hyperenhanced areas and total number of transmural hyperenhanced segments in patients with sustained VT were unexpectedly smaller than in those without. However, the percentage of nontransmural hyperenhanced segments was greater in patients with sustained VT than in those without.
Conclusions: The presence and magnitude of the nontransmural scar tissue may predict sustained VT in patients with advanced heart failure. There was the possibility that a recruitment bias was responsible for the finding of the smaller scars in the ICM patients with sustained VT.
Stretch‐Activated Receptors Mediate Cardiac Memory
Authors: KOOSHKABADI MOHAMMAD , WHALEN PATRICK , YOO DALE , LANGBERG JONATHAN 
Published: February 2009

Background: Cardiac memory refers to long‐lasting T‐wave changes that follow an episode of altered ventricular activation sequence. Memory‐induced alterations in repolarizing ion channel activity have been characterized. However, the mechanism by which changes in activation sequence produce these effects is unknown. We hypothesized that cardiac memory is mediated by the response of stretch‐activated receptors (SARs) to a change in mechanical activation sequence.
Methods: In anesthetized, closed‐chest dogs, coronary sinus leads were used to pace the posterolateral left ventricle (LV) continuously for 1 hour at a rate of 120 bpm. The surface vectorcardiogram was used to quantify cardiac memory by measuring T‐wave displacement after pacing. Streptomycin, which has been shown to block SARs, was given at a dose of 4 g intramuscularly 1 hour before experimental LV pacing sessions. T‐wave displacement after control sessions of LV pacing in the absence of drug (n = 12) was compared to that produced by pacing after streptomycin administration (n = 10 sessions).
Results: There was a distinct and consistent cardiac memory seen after 1 hour of LV pacing under control conditions, with T‐wave displacement of 1.28 ± 0.43 mV (P < 0.001 vs baseline). Pretreatment with streptomycin had no direct effect on the electrocardiogram or hemodynamics, but decreased pacing‐induced T‐wave displacement to 0.50 ± 0.28 mV (P < 0.001 vs control sessions).
Conclusions: Streptomycin, a SAR blocker, dramatically attenuated the development of cardiac memory following epicardial pacing. These data suggest that SARs are a critical link between mechanical sequence of activation and regional modulation of action potential duration that is responsible for cardiac memory.
Automatic Management of Left Ventricular Stimulation: Hints for Technologic Improvement
Authors: BIFFI MAURO , BERTINI MATTEO , SAPORITO DAVIDE , ZIACCHI MATTEO , STABELLINI SILVIA , VALSECCHI SERGIO , RICCI VALERIA , BORIANI GIUSEPPE 
Published: February 2009

Background: We used a cardiac resynchronization therapy defibrillator device with an algorithm for automatic verification of left ventricular (LV) stimulation to understand LV threshold variability, such as to provide hints to program the algorithm features. We also evaluated the algorithm performance over long term, and tested a stimulation setting to achieve 99% effective stimulation while maximizing device longevity.
Methods: The LV output was programmed as threshold + 0.5 V; the upper limit of LV output adjustment was 6 V at programmed pulse width. The algorithm is insensitive to the strength of the pacing pulse, thus pulse width was conveniently programmed to minimize the use of voltage multipliers in all the patients. Follow‐ups occurred at 1 month, then every 3 months, for clinical assessment and manual threshold verification. The efficacy of this programming at long term was also evaluated by Holter validation of LV stimulation.
Results: Twenty patients were followed for 14 ± 5 months (6–21). LV threshold showed no changes in 97% of consecutive days, whereas a 0.5‐V and 1‐V increase occurred, respectively, in 2.3% and 0.6%. Maximum variability of LV threshold was ≤0.5 V during 90% of the follow‐up period. Our programming of LV output provided 99–100% effective stimulation in 18 of 20 patients, and 90% efficacy in two patients because of missed threshold measurements. A 25% increase of device longevity can be expected by this programming.
Conclusions: LV threshold variability is truly modest. Daily update of LV threshold should be improved to ensure 100% LV stimulation by a threshold + 0.5 V safety margin. Device longevity is maximized when LV stimulation occurs below battery voltage.
Multiple Shocks Affect Thoracic Electrical Impedance During External Cardioversion of Atrial Fibrillation
Authors: FUMAGALLI STEFANO , TARANTINI FRANCESCA , CALDI FRANCESCA , MAKHANIAN YASMINE , PADELETTI MARGHERITA , BONCINELLI LORENZO , VALOTI PAOLO , DI SERIO CLAUDIA , PELLERITO SILVIA , PADELETTI LUIGI , BAROLD S. SERGE , MARCHIONNI NICCOLÒ 
Published: February 2009

Background: Thoracic impedance (TI) influences the success of external cardioversion (ECV) or defibrillation because current intensity traversing the heart is inversely related to TI. Experimental data suggest that TI decreases after multiple shocks. We undertook a clinical study to determine changes of TI values in patients with atrial fibrillation or flutter requiring ECV.
Methods: We enrolled 222 consecutive patients (age 73 ± 11 years; males 67%; body weight 75 ± 13 kg) who underwent ECV between January 2004 and February 2007. Biphasic shocks were delivered through adhesive pads placed in the anteroposterior position. The initial energy was set at 1 J/kg, with progressive increases up to a maximum of 180 J in case of failure. In the last 39 elective patients, plasma concentration of interleukin‐6 (IL‐6) and tumor necrosis factor (TNF)‐α were determined before and 6 hours after ECV.
Results: Sinus rhythm was restored in 202 patients (91.0%). Of these, 155 (69.8%) required more than one shock (on average, 2.5 ± 1.5 shocks/patient). Final values of energy and peak current intensity were 136 ± 47 J and 50 ± 14 A, respectively. TI decreased significantly by 6.2% from baseline after ≥2 shocks (P < 0.001). The absolute reduction was correlated with baseline TI, number of delivered shocks, and hemoglobin oxygen saturation. IL‐6 and TNF‐α increased with ECV (P < 0.001 and P = 0.014, respectively).
Conclusions: TI decreases significantly after multiple shocks, possibly by activation of acute inflammation.
Postoperative Low‐Molecular‐Weight Heparin Bridging Is Associated with an Increase in Wound Hematoma Following Surgery for Pacemakers and Implantable Defibrillators
Authors: ROBINSON MARLENE , HEALEY JEFF S. , EIKELBOOM JOHN , SCHULMAN SAM , MORILLO CARLOS A. , NAIR GIRISH M. , BARANCHUK ADRIAN , RIBAS SEBASTIAN , EVANS GEOFF , CONNOLLY STUART J. , TURPIE ALEXANDER G. 
Published: February 2009

Background: The perioperative management of patients receiving oral anticoagulation therapy (OAC) who undergo pacemaker (PM) and defibrillator (ICD) surgery remains controversial. Low‐molecular‐weight heparin (LMWH) is often used; however, wound hematoma is a common complication.
Methods: At a single academic Canadian center, between July 2003 and June 2005, details of perioperative OAC bridging and the rate of wound hematoma requiring reoperation or interruption of OAC were reviewed for all patients receiving LMWH bridging for PM or ICD surgery.
Results: A total of 148 PM/ICD patients underwent perioperative bridging with LMWH. A significant hematoma occurred in 23 patients, requiring reoperation in three patients. No patient died, developed infection, or stroke. The initial bridging regimen included LMWH (enoxaparin 1 mg/kg BID) given until evening prior to surgery, and reinitiated on postoperative day 3. In response to high rates of postoperative hematoma, subsequent protocols omitted the LMWH on the evening before surgery, all postoperative LMWH, or both. The use of LMWH the night before surgery had no effect on hematoma rates (12% vs 17%, P = 0.62); however, the use of any postoperative LMWH increased hematoma rates (23% vs 8%, P = 0.01). Hematoma rates were not increased in patients receiving acetylsalicylic acid (19% vs 16%, P = 0.62) or clopidogrel (25% vs 17%, P = 0.54). In a multivariate analysis, independent predictors of significant wound hematoma included postoperative LMWH (P = 0.001), a higher international normalized ratio on the day of surgery (P = 0.03), and male sex (P = 0.05).
Conclusion: Elimination of postoperative LMWH was associated with a substantial reduction in hematoma rates following PM and ICD surgery.
Progress of multiple cutaneous and subcutaneous melanoma metastases of the face during imiquimod treatment
Authors: Kowalzick Lutz , Eickenscheidt Lena 
Published: February 2009

SummaryA 68‐year‐old man developed a local recurrence with multiple cutaneous and subcutaneous nodules three months after excision of a primary malignant melanoma of the temple. Despite extensive surgery and adjuvant irradiation, another local recurrence occurred. Following further local progression during dacarbazine chemotherapy, topical treatment with imiquimod was begun and the chemotherapy was changed to fotemustine. During this treatment further local progression occurred and two months later regional lymph node and distant metastasis were detected. The patient died from his tumor disease eighteen months after the first diagnosis of malignant melanoma.
Changes in plant communities over three decades on two disturbed bogs in southeastern Québec
Authors: Pellerin S. , Mercure M. , Desaulniers A.S. , Lavoie C. 
Published: February 2009

AbstractQuestions: Have the natural plant communities of two mined bogs experienced changes in composition and richness over a three‐decade period, and are these changes associated with anthropogenic disturbances?Location: Bas‐Saint‐Laurent region, southeastern Québec, Canada.Methods: We monitored three decades of floristic changes in two disturbed bogs by revisiting 57 plots in 1998, which were previously sampled in 1965 and 1966. Changes in species richness and composition were evaluated using Wilcoxon signed rank tests, principal component analysis and partial redundancy analyses (pRDA). We also used pRDA and an indicator species analysis to determine which species had undergone the greatest changes over time. Variation partitioning was used to evaluate the relative influence of human disturbance in compositional change.Results: The main changes in the vegetation of the two bogs were 1) a decrease of overall species diversity, 2) an increase in the percent cover of trees and of species tolerant of shade or drought, and 3) a decrease in the cover of heliophilous species. Picea mariana, Sphagnum fuscum and Pleurozium schreberi increased in percent cover while Chamaedaphne calyculata and Sphagnum rubellum decreased in percent cover. Variation partitioning suggested that human activities had a significant impact on vegetation composition.Conclusion: The results indicated that substantial changes occurred in the vegetation of the natural fragments of these severely disturbed bogs. Although human activities were partially responsible for the changes, our study suggested that the drying of the peat surface due to drought during the 1960s and 1980s may have contributed to the vegetation changes.
Niche breadth rather than reproductive traits explains the response of wetland monocotyledons to land‐cover change
Authors: Pino Joan , Vilà Montserrat , Álvarez Nora , Seguí Josep Maria , Guerrero Charo 
Published: February 2009

AbstractQuestion: We hypothesised that, even within the same plant functional group, there are specific distributions in land‐cover classes and with land‐cover change that are associated with niche breadth rather than reproductive strategy, and that the broader the niche of the species the better they cope with different land‐cover classes and changes over time.Location: The Llobregat Delta (Barcelona, Spain).Methods: We analysed the distribution pattern of eight coexisting wetland perennial monocotyledons within human disturbance classes (obtained from the classification of land‐cover categories in relation to their level of human disturbance) and changes in such classes from 1956 to 1999. We then compared species regional abundance and distribution patterns with seed dispersal type (wind dispersed versus non‐wind dispersed species), vegetative spread (tussock versus caespitose‐running species), and niche breadth (the number of phytosociological alliances in which each species is found).Results: Regional abundance of the species was positively related to niche breadth, but was independent of reproductive traits. Similarly, distribution in human disturbance classes and their changes were associated with niche breadth rather than reproductive traits. In general, the more specialist the species, (i) the more they are concentrated in natural habitats, (ii) the less land‐cover changes they are able to cope with, and (iii) the more they are restricted to stable change types, particularly to longstanding natural areas.Conclusions: Ecological plasticity rather than dispersal capacity of dominant perennial monocotyledons determines their regional abundance and their ability to cope with recent and future land‐cover changes in Mediterranean wetlands. As habitat specialists are less resistant to landscape change than generalists, floristic homogenisation may progress in these habitats with the likely scenario of increasing land‐cover turnover.
Savanna dynamics in central Texas: just succession?
Authors: Fowler Norma L. , Simmons Mark T. 
Published: February 2009

AbstractQuestion: What is the best way to model savanna dynamics? Specifically, under what conditions is a traditional succession model, i.e., a model of ordered, uni‐directional change in the plant community, better than a state‐and‐transition model?Location: Central Texas savannas.Methods: We describe three examples of successional processes in central Texas savannas: (a) woody plant encroachment, (b) invasion by a non‐native grass, and (c) establishment of different grass species in highly disturbed sites.Results and Conclusions: Savanna dynamics are now commonly conceptualized with state‐and‐transition models. However, in some situations a traditional succession model may be more appropriate or more useful. Succession models may better fit current ecological reality, as found in central Texas. Succession models emphasize transient dynamics rather than an (often unknown) endpoint, and direct us towards relevant literature from non‐savanna ecosystems. Succession models may be particularly useful for land management and restoration, and where woody plant encroachment and/or invasions by non‐native species control vegetation dynamics.
Soil fertility, heterogeneity, and microbes: towards an integrated understanding of grassland structure and dynamics
Authors: Reynolds Heather L. , Haubensak Karen A. 
Published: February 2009

AbstractObjective: To highlight the need and the potential for an integrated understanding of three key soil‐based drivers of plant community structure and dynamics – soil fertility, soil heterogeneity, and microbes.Location: European and North American grasslands.Methods: Review and discussion of conceptual models and empirical literature, including examples of observational and manipulative studies from both natural and restored grassland communities.Results and Conclusions: In general, the results of empirical studies on soil fertility, soil heterogeneity, and soil microbes in grassland communities do not support expectations of common conceptual models. Ecological theory assumes a unimodal relationship between soil fertility and plant community diversity, yet empirical relationships from grassland communities are variable, the mechanisms underlying these variable patterns are not yet well understood, and there is mixed success at manipulating soil fertility to facilitate restorations. While theory predicts that increased soil heterogeneity will lead to increased plant community diversity, results of experimental manipulations of soil heterogeneity often show the opposite. Of two major conceptual models proposed for how microbes structure plant communities, there is little support for the hypothesis of microbially mediated niche partitioning. Plant‐microbe feedbacks do have significant empirical support to date and there is increasing application of positive feedback dynamics in restoration, yet field tests of feedback dynamics remain limited. We suggest that an understanding of interactions between these soil drivers may help to resolve discrepancies between conceptual models and empirical results, improving our understanding of grasslands and our ability to restore them.