bluuebunny/crossref_metadata_2025 huggingface dataset:
Tracking the origin of an invasive species: Drosophila subobscura in Argentina
Authors: FERNÁNDEZ IRIARTE P. J. , BALANYÀ J. , PASCUAL M. , MESTRES F. , HASSON E. R. , FONTDEVILA A. , SERRA L.
Published: December 2008

Biological invasions are excellent opportunities to study the evolutionary forces leading to the adaptation of a species to a new habitat. Knowledge of the introduction history of colonizing species helps tracking colonizing routes and assists in defining management strategies for invasive species. The Palearctic species Drosophila subobscura is a good model organism for tracking colonizations since it was detected in Chile and western North America three decades ago and later on in the Atlantic coast of Argentina. To unravel the origin of the Argentinean colonizers two populations have been analysed with several genetic markers. Chromosomal arrangements and microsatellite alleles found in Argentina are almost similar to those observed in Chile and USA. The lethal allelism test demonstrates that the lethal gene associated with the O5 inversions in Argentina is identical to that found in Chile and USA, strongly supporting the hypothesis that all the American colonizing populations originated from the same colonization event. A secondary bottleneck is detected in the Argentinean populations and the genetic markers suggest that these populations originated from the invasion of 80–150 founding individuals from Chile.
Selective nectar robbing in a gynodioecious plant (Glechoma longituba) enhances female advantage
Authors: ZHANG Y.‐W. , YANG C.‐F. , ZHAO J.‐M. , GUO Y.‐H.
Published: December 2008

Nectar robbing not only affects the reproductive fitness of the plant but it may also potentially affect the pollination dynamics of the associated coflowering individuals. In this study, we established that the nectar robber Xylocopa sinensis robs nectar only from the hermaphrodite ramets of the gynodioecious plant Glechoma longituba but not from the female ramets. In populations with high rates of nectar robbing, this results in hermaphrodite ramets having reduced seed set whereas the female ramets have a slightly increased seed set. We hypothesize that selective nectar robbing confers an advantage to female individuals and thus ensures their maintenance in gynodioecious populations. Results of controlled experiments indicated that the reduction in the amounts of nectar available occasioned by nectar robbing resulted in some legitimate pollinators switching to visiting flowers on female rather than hermaphrodite ramets. This resulted in lower pollination rates and seed set for hermaphrodites and higher pollination rates and seed set for females. This study presents a previously unreported mechanism causing female advantage in gynodioecious plants.
Divergence along a steep ecological gradient in lake whitefish (Coregonussp.)
Authors: VONLANTHEN P. , ROY D. , HUDSON A. G. , LARGIADÈR C. R. , BITTNER D. , SEEHAUSEN O.
Published: December 2008

To understand mechanisms structuring diversity in young adaptive radiations, quantitative and unbiased information about genetic and phenotypic diversity is much needed. Here, we present the first in‐depth investigation of whitefish diversity in a Swiss lake, with continuous spawning habitat sampling in both time and space. Our results show a clear cline like pattern in genetics and morphology of populations sampled along an ecological depth gradient in Lake Neuchâtel. Divergent natural selection appears to be involved in shaping this cline given that trait specificPST‐values are significantly higher thanFST‐values when comparing populations caught at different depths. These differences also tend to increase with increasing differences in depth, indicating adaptive divergence along a depth gradient, which persists despite considerable gene flow between adjacent demes. It however remains unclear, whether the observed pattern is a result of currently stable selection‐gene flow balance, incipient speciation, or reverse speciation due to anthropogenic habitat alteration causing two formerly divergent species to collapse into a single gene pool.
Differentiation and Genetic Structure of Sclerophoma pythiophila Strains on Pinus sylvestris in Poland
Authors: Kraj Wojciech
Published: December 2008

Between 1996 and 2006, 97 strains of Sclerophoma pythiophila were isolated from 3 to 10‐year‐old trees of Pinus sylvestris from three regions of Poland differing by climatic conditions and geographic location. On the basis of 56 random amplified microsatellites (RAMS) markers obtained with the use of five primers, very high level of genetic variability of strains (mean Jaccard’s coefficient 0.56) was ascertained. Among the analysed markers only one was completely monomorphic, whereas six were monomorphic in 90%. Greater genetic similarity was ascertained for strains in southern Poland (0.58) in comparison with strains deriving from northern Poland (0.52). Correlation between the percentage share of polymorphic loci and the average annual temperature of places of strain isolation (r = 0.62) were shown, as well as the number of days with snow cover (r = 0.79). On the basis of the amova analysis, it was ascertained that 11.6% of genetic variability was located between regions of the strains origin and 88.4% within the regions.
Economic development lessons from and for North American Indian economies*
Authors: Anderson Terry L. , Parker Dominic P.
Published: December 2008

This paper reviews the literature on economic development as it relates to indigenous people in the United States and Canada, and focuses on how institutions affect economic development of reservation and reserve economies. Evidence shows that strong property rights to reservation and reserve land and natural resources, whether communal or individual, are and always have been important determinants of productivity. Political and legal institutions that are perceived as stable and predictable to tribal members and to non‐Natives also improve economic opportunities for indigenous people living on reservations and reserves. Research reviewed here also shows that culture and acculturation are important in the development process. Although our emphasis is on North America, the findings are applicable to indigenous people in other parts of the world and shed light on growth questions that loom large for developing countries around the world.
Encumbering harvest rights to protect marine environments: a model of marine conservation easements*
Authors: Deacon Robert T. , Parker Dominic P.
Published: December 2008

We adapt the concept of a conservation easement to a marine environment and explore its use to achieve conservation goals. Although marine environments generally are not owned, those who use them for commercial fishing often are regulated. These regulations grant harvesters rights to use marine environments in specified ways, and the possibility of encumbering these rights to achieve conservation goals creates a potential role for marine easements. We examine this potential under alternative fishery management regimes and find, generally, that marine easements tend to be most effective when harvest rights are delineated most fully. Our analysis suggests ways that marine easements can have flexibility and transactions cost advantages over other approaches to achieve marine conservation goals. We also propose ways in which the design of laws allowing marine easements should follow, or depart from, the design of laws authorising conservation easements on land.
Ideas and Growth
Authors: LUCAS ROBERT E.
Published: December 2008

This paper introduces and partially develops a new model of endogenous technological change, viewed as the product of a class of problem‐solving producers. The model, based on earlier work by Eaton and Kortum, is built up from the premise that all knowledge resides in the head of some individual person and the knowledge of a firm, or economy, or any group of people is simply the knowledge of the individuals that comprise it. The model is applied to an economy with a cohort structure. A calibration of the model using cross‐section earnings data, in addition to aggregate GDP growth, is considered.
Clinical features of convulsive status epilepticus: a study of 220 cases in western China
Authors: Chen L. , Zhou B. , Li J. M. , Zhu Y. , Wang J. H. , Sander J. W. , Stefan H. , Zhou D.
Published: December 2008

Background and purpose:  Convulsive status epilepticus (CSE) is the most common and life‐threatening form of status epilepticus (SE). The aim of this study was to describe the clinical features of CSE in western China.

Methods:  Convulsive status epilepticus patients hospitalized from January 1996 to October 2007 were prospectively observed. Logistic regression was used to identify predictors of prognosis.

Results:  The average age of CSE patients (n = 220) was 37.5 years (SD 20.31), 50% of the patients had a history of epilepsy. The primary cause of CSE was central nervous system infection (32.7%), followed by discontinuation or reduction of antiepileptic drugs (AEDs; 15.5%). The median duration of CSE was 5 h and median duration of seizures before treatment was 2 h; both were longer in rural patients than in urban patients (P < 0.05). The fatality rate on discharge was 15.9%. Logistic regression analysis showed the duration of CSE [odds ratio (OR) 1.05, 95% confidence interval (CI) 1.03–1.07], a history of epilepsy (OR 0.35, 95% CI 0.14–0.89), and respiratory depression (OR 5.96, 95% CI 2.49–14.24) were independent predictors of CSE prognosis.

Discussion:  Central nervous system infection and AEDs withdrawal in epilepsy patients were the most important causes of CSE. There is a large gap between antiepileptic therapy in China and European Status Epilepticus guidelines.
Electrophysiological correlates of decreasing and increasing emotional responses to unpleasant pictures
Authors: Moser Jason S. , Krompinger Jason W. , Dietz Jenna , Simons Robert F.
Published: December 2008

We examined event‐related brain potential (ERP) modulations during the anticipation and processing of unpleasant pictures under instructions to cognitively decrease and increase negative emotion. Instructions to decrease and increase negative emotion modulated the ERP response to unpleasant pictures in the direction of emotional intensity beginning around 400 ms and lasting several seconds. Decrease, but not increase, instructions also elicited enhanced frontal negativity associated with orienting and preparation prior to unpleasant picture onset. Last, ERP modulation by unpleasant pictures began around 300 ms, just prior to regulation effects, suggesting that appraisal of emotion occurs before emotion regulation. Together, the current findings underscore the utility of ERPs in illuminating the time course of emotion modulation and regulation that may help to refine extant theoretical models.
ERP correlates of transposed‐letter priming effects: The role of vowels versus consonants
Authors: Carreiras Manuel , Vergara Marta , Perea Manuel
Published: December 2008

One key issue for any computational model of visual‐word recognition is the choice of an input coding scheme for assigning letter position. Recent research has shown that pseudowords created by transposing two letters are very effective at activating the lexical representation of their base words (e.g., relovution activates REVOLUTION). We report a masked priming lexical decision experiment in which the pseudoword primes were created by transposing/replacing two consonants or two vowels while event‐related potentials were recorded. The results showed a modulation of the amplitude at an early window (150–250 ms) and at the N400 component for vowels but not for consonant transpositions. In addition, the peak latencies were faster for transposed than replaced consonants. These results suggest that consonants and vowels play a different role during the process of visual word recognition. We examine the implications for the choice of an input coding scheme in models of visual‐word recognition.
Expertise, language competencies and the L2 user
Authors: Vickers Caroline H.
Published: December 2008

The purpose of this paper is to demonstrate the relationship between embodied experience in the world and language competence. Primary data consists of audio and video recorded team meetings among NS and NNS engineering students in an English‐speaking American university and ethnographic fieldwork. Based a micro‐interactional analysis of the primary data and a consideration of how this analysis is embedded within the macro‐social context, findings demonstrate how the L2 user is locally constructed as legitimate and as expert relative to the L1 user in terms of engineering competence and language competence. In the end, these two engineers co‐construct a unique way of engaging in engineering teamwork that follows from an acceptance of positionalities that allows opportunities for learning.
Tissue‐Engineered Skin Containing Mesenchymal Stem Cells Improves Burn Wounds
Authors: Liu Peng , Deng Zhihong , Han Shufang , Liu Tao , Wen Ning , Lu Wei , Geng Xianhui , Huang Sha , Jin Yan
Published: December 2008

There is increasing evidence showing that adult stem cells are useful for tissue regeneration. Bone marrow mesenchymal stem cells (MSCs) are self‐renewing and are potent in differentiating into multiple cells and tissues. To investigate the practicability of repairing burn wounds with tissue‐engineered (TE) skin combined with bone MSCs, we established a burn wound model in the porcine skin. With a controlling temperature and time of the burning device to obtain different degrees of burn wounds, a deep dermal partial thickness burn was introduced to the porcine skin using a heated‐brass contact injury at 100°C for 20 s. Collagen‐GAG scaffolds were utilized as the matrix; MSCs separated from pigs were seeded on them to form the skin equivalent. When grafted to the burn wounds, the TE skin containing MSCs showed better healing and keratinization, less wound contraction, and more vascularization. Grafts proliferated well and contributed to the neo‐tissues. These data suggest that TE skin containing MSCs in a burn defect can accelerate wound healing and receive satisfactory effects.
Changes in Atrial Natriuretic Peptide Levels During Cardiac Bypass in the Fetal Goat
Authors: Zhou Chengbin , Zhuang Jian , Zhang Xiaohua , Zhang Jinfang
Published: December 2008

The aim of this study is to evaluate the effect of fetal cardiac bypass on the production and secretion of fetal atrial natriuretic peptide (ANP) in the goat. Eighteen pregnant goats, at days 120 to 140 of gestation, were randomly divided into control (n = 8) and bypass (n = 10) groups. The control group underwent a sham procedure involving fetal sternotomy and cannulation. The bypass group underwent fetal cardiac bypass using a centrifugal pump for 30 min. Fetuses in the bypass group exhibited hypoxia, hypercapnia, and acidosis during and after cardiac bypass. The pulse index (PI) of the umbilical artery in the bypass group increased significantly after cardiac bypass compared with the control group. Tei indices of the left and right ventricles in the bypass group increased remarkably after cardiac bypass. Plasma troponin I levels in the bypass group increased significantly compared with that of the control group. Plasma ANP levels increased markedly in the bypass group after cardiac bypass, and the difference between two groups was significant. Transcriptional levels of ANP mRNA in the fetal heart elevated remarkably in the bypass group compared with the control group at 2 h after the bypass. A significant positive correlation between plasma ANP levels and Tei indices of the ventricles, plasma troponin I was observed (left ventricular Tei index, r =  0.606, P < 0.01; right ventricular Tei index, r = 0.581, P <  0.01; plasma troponin I, r = 0.275, P < 0.05). In conclusion, fetal cardiac bypass promoted the production and secretion of ANP and was associated with fetal cardiac dysfunction.
The prevalence of abnormal results of conventional coagulation tests on admission to a trauma center
Authors: Hess John R. , Lindell Allison L. , Stansbury Lynn G. , Dutton Richard P. , Scalea Thomas M.
Published: December 2008

BACKGROUND: Several groups have reported that a fraction of severely injured patients have abnormal coagulation tests at presentation to trauma centers, even in the absence of significant crystalloid resuscitation. These patients have high mortality, but their prevalence in trauma populations is not clear from the reports.

STUDY DESIGN AND METHODS: Records of all patients admitted to a large urban trauma center during 2000 through 2006 were searched for early measures of common coagulation tests and in‐hospital mortality.

RESULTS: Abnormal coagulation tests were increasingly frequent with increasing injury severity, ranging from 5 to 43 percent for the prothrombin time as the injury severity scores (ISSs) increased from 5 to more than 45 and 4 to 18 percent for platelet counts of less than 150 × 109 per L. Abnormal coagulation tests were associated with excess mortality even below conventional transfusion triggers and this was especially true for the partial thromboplastin time.

CONCLUSIONS: Abnormal coagulation tests are common in severely injured patients. Even in the moderately injured, they are associated with higher mortality.
Permanent Pacemaker Implantation Following Cardiac Surgery: Indications and Long‐Term Follow‐Up
Authors: MERIN OFER , ILAN MICHAEL , OREN AVRAHAM , FINK DANIEL , DEEB MAHER , BITRAN DANI , SILBERMAN SHULI
Published: December 2008

Background: Conduction disturbances requiring permanent pacemaker implantation after heart surgery occur in about 1.5% of patients. Early pacemaker implantation may reduce morbidity and postoperative hospital stay. We reviewed our experience with patients undergoing surgery to try and identify predictors for pacemaker requirements and patients who will remain pacemaker dependent.

Methods: We performed a retrospective review of 4,999 patients undergoing surgery between the years 1993 and 2005. Patient age was 64 ± 12 years, and 71% were males. Coronary bypass was performed in 4,071 (81%), aortic valve replacement in 675 (14%), and mitral valve replacement in 968 (18%) patients.

Results: Seventy‐two patients (1.4%) required implantation of a permanent pacemaker after surgery. Indications for pacemaker implantation included complete atrioventricular block in 59, symptomatic bradycardia/slow atrial fibrillation in nine, second‐degree atrioventricular block in two, and other conduction disturbances in two patients. Predictors for pacemaker requirement by multivariate analysis were left bundle branch block and aortic valve replacement (P < 0.001). Late follow‐up was available in 58 patients, at 72 ± 32 months. Thirty‐seven (63%) were pacemaker dependent. Predictors for late pacemaker dependency were third‐degree atrioventricular block after surgery and preoperative left bundle branch block (P < 0.001).

Conclusions: Patients at high risk for pacemaker implantation after heart surgery include those with preexisting conduction disturbances, and those undergoing aortic valve replacement. Of those receiving a pacemaker, about one‐third will recover at late follow‐up. For patients in the high‐risk group who are pacemaker dependent after surgery, we recommend implanting a permanent pacemaker at 5 days after surgery, thus enabling early mobilization and early discharge.
Clustering of Poor Device Acceptance and Type D Personality is Associated with Increased Distress in Danish Cardioverter‐Defibrillator Patients
Authors: PEDERSEN SUSANNE S. , SPINDLER HELLE , JOHANSEN JENS B. , MORTENSEN PETER T.
Published: December 2008

Background: Psychosocial risk factors tend to cluster together within individuals, likely enhancing the risk of adverse health outcomes. We examined (1) the influence of clustering of poor device acceptance and Type D personality on anxiety and depressive symptoms, and (2) the demographic and clinical determinants of patients with clustering, in a large cohort of Danish implantable cardioverter defibrillator (ICD) patients.

Methods: Patients (N = 557; 81.9% male; mean age = 61.9 ± 14.3 years) implanted with an ICD between 1989 and 2006 were asked to complete a set of standardized and validated questionnaires and were divided into four risk groups: (1) No risk factors (neither poor device acceptance nor Type D), (2) Poor device acceptance only, (3) Type D only, (4) Clustering (both poor device acceptance and Type D).

Results: The prevalence of anxiety was significantly higher in patients with clustering of risk factors (54.2%) compared to patients with poor device acceptance (30.0%), Type D personality (26.5%), or no risk factors (7.6%) (χ2= 88.472; df = 3; P < 0.001). Similarly, the prevalence of depression was higher in the clustering group (47.2%) compared to patients with poor device acceptance (19.1%), Type D personality (23.5%), or no risk factors (1.8%) (Fisher's exact = 112.874; df = 3; P < 0.001). Patients with the clustering of poor device acceptance and Type D had the highest mean scores of anxiety (P < 0.001) and depression (<0.001), also when adjusting for demographic and clinical baseline characteristics including shocks. Shocks (P = 0.006) were associated with increased anxiety but not with depression (P = 0.31).

Conclusion: Patients with poor device acceptance and Type D personality should be identified and monitored in clinical practice, as they may benefit from adjunctive intervention in order to experience the same quality of life benefits following implantation as other patients. Given the cross‐sectional nature of the study, these findings should be confirmed using a prospective study design.
Epsilon Wave in Arrhythmogenic Right Ventricular Dysplasia/Cardiomyopathy
Authors: WU SHULIN , WANG PEINING , HOU YUESHUANG , YANG PINGZHEN , XIAO YANPING , ZHAN XIANZHANG
Published: December 2008

Background: Epsilon wave is a major criteria for arrhythmogenic right ventricular (RV) dysplasia/cardiomyopathy (ARVD/C). We sought to study systematically characteristics of Epsilon wave in ARVD/C patients from the southern Chinese population.

Methods: The population included 49 patients with ARVD/C meeting the diagnostic criteria. They were analyzed for the value of different electrocardiogram (ECG) criteria including Epsilon wave, the ones of 24‐hour Holter recording, signal‐averaged ECG, and echocardiography to learn the correlation between Epsilon wave and other variability with the use of nonparametric test. A probability value of ≤0.05 was considered significantly different.

Results: It shown that the detection rate of Epsilon wave was significantly higher in probands (65%) than involved family members (22%), P = 0.03. In the conventional as well as Fontaine leads, its detection rate were 18 (37%) and 28 (57%), respectively. The prevalence of diffuse right ventricle involvement, T‐wave inversion and signal‐averaged ECG are significantly different between the ARVD/C patients with Epsilon wave and without Epsilon wave.

Conclusion: It is significantly correlated between Epsilon wave and the progressive ARVD/C.
QT Interval Variability and Adaptation to Heart Rate Changes in Patients with Long QT Syndrome
Authors: NĚMEC JAN , BUNCOVÁ MARIE , SHUSTERMAN VLADIMIR , WINTER BRUCE , SHEN WIN‐KUANG , ACKERMAN MICHAEL J.
Published: December 2008

Background: Increased QT variability (QTV) has been reported in conditions associated with ventricular arrhythmias. Data on QTV in patients with congenital long QT syndrome (LQTS) are limited.

Methods: Ambulatory electrocardiogram recordings were analyzed in 23 genotyped LQTS patients and in 16 healthy subjects (C). Short‐term QTV was compared between C and LQTS. The dependence of QT duration on heart rate was evaluated with three different linear models, based either on the RR interval preceding the QT interval (RR0), the RR interval preceding RR0 (RR‐1), or the average RR interval in the 60‐second period before QT interval (mRR).

Results: Short‐term QTV was significantly higher in LQTS than in C subjects (14.94 ± 9.33 vs 7.31 ± 1.29 ms; P < 0.001). It was also higher in the non‐LQT1 than in LQT1 patients (23.00 ± 9.05 vs 8.74 ± 1.56 ms; P < 0.001) and correlated positively with QTc in LQTS (r = 0.623, P < 0.002). In the C subjects, the linear model based on mRR predicted QT duration significantly better than models based on RR0 and RR‐1. It also provided better fit than any nonlinear model based on RR0. This was also true for LQT1 patients. For non‐LQT1 patients, all models provided poor prediction of QT interval.

Conclusions: QTV is elevated in LQTS patients and is correlated with QTc in LQTS. Significant differences with respect to QTV exist among different genotypes. QT interval duration is strongly affected by noninstantaneous heart rate in both C and LQT1 subjects. These findings could improve formulas for QT interval correction and provide insight on cellular mechanisms of QT adaptation.
Ventricular Proarrhythmic Effects of Atrial Fibrillation are Modulated by Depolarization and Repolarization Anomalies in Patients with Left Ventricular Dysfunction
Authors: LEMOLA KRISTINA , KHAN RAZI , NATTEL STANLEY , TALAJIC MARIO , ROY DENIS , GUERRA PETER G. , LEMOLA SAKARI , DUBUC MARC , THIBAULT BERNARD , MACLE LAURENT , KHAIRY PAUL
Published: December 2008

Background: Atrial fibrillation (AF) may have a ventricular proarrhythmic effect, particularly in the setting of heart failure. We assessed whether AF predicts appropriate implantable cardioverter‐defibrillator (ICD) shocks in patients with left ventricular dysfunction and explored modulators of risk.

Methods and Results: A retrospective cohort study was conducted on 215 consecutive patients with ICDs for primary prevention having a left ventricular ejection fraction ≤ 35%. Mean age at ICD implantation was 61.0 ± 9.7 years and 17% were women. Overall, 22 patients (10.2%) experienced appropriate ICD shocks over a follow‐up of 1.3 ± 0.7 years, corresponding to an actuarial event‐rate of 5.8% per year. In univariate analysis, AF was associated with a 3.6‐fold increased risk of appropriate shocks (P = 0.0037). Annual rates of appropriate ICD shocks in patients with and without AF were 12.9% and 3.5%, respectively (P = 0.0200). In multivariate stepwise Cox regression analyses controlling for baseline imbalances, demographic parameters, underlying heart disease, and therapy, history of AF independently predicted appropriate shocks (hazard ratio 2.7, P = 0.0278). Prolonged QRS duration (>130 ms) and QTc (>440 ms) modulated the effect of AF on appropriate shocks. Patients with both AF and QRS > 130 ms were more than five times more likely to receive an appropriate ICD shock (hazard ratio 5.4, P = 0.0396). Patients with AF and QTc > 440 ms experienced a greater than 12‐fold increased risk of appropriate shocks (hazard ratio 12.7, P = 0.0177).

Conclusion: In prophylactic ICD recipients with left ventricular dysfunction, AF is associated with increased risk for ventricular tachyarrhythmias, particularly when combined with conduction and/or repolarization abnormalities.
Drug Therapy for Atrial Fibrillation: What Will Its Role Be in the Era of Increasing Use of Catheter Ablation?
Authors: MORROW JOHN P. , REIFFEL JAMES A.
Published: December 2008

Atrial fibrillation (AF) is an increasingly important disorder. In most patients the treatment of AF usually employs anti‐arrhythmic drugs (AADs). Despite the widespread utilization of AADs for the conversion of atrial fibrillation and maintenance of normal sinus rhythm, their use is limited by modest efficacy, frequent intolerance, and the potential for serious ventricular proarrhythmia and organ toxicity. In addition to AADs, ablations for AF have come into vogue. If ablation techniques improve, one might ask whether there will still be a role for AADs, and, if so, what will it be and what agents will be used. This manuscript will attempt to answer these questions.
Strategy to Eliminate Inappropriate Shocks Secondary to T‐Wave Oversensing in a Biventricular ICD
Authors: SILVER JONATHAN S. , GRAY MARY ELLEN , JOHN ROY M.
Published: December 2008

T‐wave oversensing represents a common cause of inappropriate shocks in patients with implanted cardiac defibrillators. This case report demonstrates a strategy of device programming using V‐V pace delay (sequential rather than simultaneous biventricular pacing) to eliminate T‐wave oversensing without decreasing sensitivity to detect true tachyarrhythmia.
Is Flecainide Dangerous in Long QT‐3 Patients?
Authors: BEINART ROY , MICHAILIDIS ATHANASIOS , GUREVITZ OSNAT T. , GLIKSON MICHAEL
Published: December 2008

Mutations of the cardiac sodium channel gene, SCN5A, are present in both long‐QT and Brugada syndromes. Flecainide is used as a provocative test to unmask the electrocardiogram (ECG) phenotype of the Brugada syndrome, as well as long‐term treatment for long QT‐3 syndrome, since it shortens the QT interval. We report a case where oral flecainide induced syncope with a Brugada ECG pattern in a patient with known long QT‐3 syndrome.
The benefits of being in a bad neighbourhood: plant community composition influences red deer foraging decisions
Authors: Bee Jennie N. , Tanentzap Andrew J. , Lee William G. , Lavers Roger B. , Mark Alan F. , Mills James A. , Coomes David A.
Published: December 2008

Diet selection by mammalian herbivores is often influenced by plant community composition, and numerous studies have focused on the relationships between herbivore foraging decisions and food/plant species abundance. However, few have examined the role of neighbour palatability in affecting foraging of a target plant by large mammalian herbivores. We used a large‐scale field dataset on diet selection by red deer Cervus elaphus in Fiordland National Park, New Zealand to: (1) estimate the palatability of native forest plant species to introduced deer from observed patterns of browse damage; and (2) examine whether intraspecific variation in browsing of plants can be related to variation in the local abundance of alternative forage species. Overall, 21 of the 53 forest species in our dataset were never browsed by deer. At a community level, plants were more likely to be browsed if they were in a patch of vegetation of high forage quality, containing high abundances of highly palatable species and/or low abundances of less‐palatable species. Our findings suggest that deer make foraging decisions at both a coarse‐grain level, selecting vegetation patches within a landscape based on the overall patch quality, and at a fine‐grain level by choosing among individual plants of different species.
The dynamics of climate‐induced range shifting; perspectives from simulation modelling
Authors: Mustin Karen , Benton Tim G. , Dytham Calvin , Travis Justin M. J.
Published: December 2008

Predicted future climate change will alter species’ distributions as they attempt to track the most suitable ‘climate window’. Climate envelope models indicate the direction of likely range changes but do not incorporate population dynamics, therefore observed responses may differ greatly from these projections. We use simulation modelling to explore the consequences of a period of environmental change for a species structured across an environmental gradient. Results indicate that a species’ range may lag behind its climate envelope and demonstrate that the rate of movement of a range can accelerate during a period of climate change. We conclude that the inclusion of both population dynamics and spatial environmental variability is vital to develop models that can both predict, and be used to manage, the impact of changing climate on species’ biogeography.
MORPHOLOGY OF THE CAUDAL FOSSA IN CAVALIER KING CHARLES SPANIELS
Authors: CERDA‐GONZALEZ SOFIA , OLBY NATASHA J. , McCULLOUGH SUSAN , PEASE ANTHONY P. , BROADSTONE RICHARD , OSBORNE JASON A.
Published: December 2008

Chiari malformations and syringohydromyelia are an important disease complex in Cavalier King Charles Spaniels. Although abnormalities in caudal fossa morphology are considered major contributors to the development of this disease, limited information exists on the range of morphologies in Cavalier King Charles Spaniels and on the relationship of these to clinically evident disease. Sixty‐four Cavalier King Charles Spaniels were studied. Each underwent a neurologic examination and magnetic resonance imaging of the cervical spine and brain. T2‐weighted sagittal images were used to determine both the morphologic characteristics and volume of the caudal fossa in each dog. This volume was also analyzed as a percentage of total cranial cavity volume. Each attribute was correlated with neurological grade and presence of syringohydromyelia. Fifteen dogs had neurologic signs, and 59 had morphologic abnormalities of the craniocervical junction. While 27 dogs had syringohydromyelia, 13 of these were clinically normal. Cerebellar herniation and occipital dysplasia were common findings but were not associated with syringohydromyelia. Dorsal compressive lesions were noted at the first and second cervical vertebral junction. Factors associated with the presence of neurologic signs included syringohydromyelia and the ratio of caudal fossa/total cranial cavity volume; dogs with signs had significantly larger syringohydromyelia than asymptomatic dogs. Caudal fossa size was not associated with syringohydromyelia. A positive association was identified between foramen magnum size and length of cerebellar herniation. The prevalence of craniocervical junction abnormalities is high in Cavalier King Charles Spaniels. While several factors are associated with neurologic signs, occipital hypoplasia appears to be the most important factor.
QUANTITATIVE CONTRAST‐ENHANCED ULTRASONOGRAPHY OF CANINE SPLEEN
Authors: NAKAMURA KENSUKE , SASAKI NOBORU , YOSHIKAWA MUNEYOSHI , OHTA HIROSHI , HWANG SHIANG‐JYI , MIMURA TAKAHIRO , YAMASAKI MASAHIRO , TAKIGUCHI MITSUYOSHI
Published: December 2008

Contrast‐enhanced ultrasonography has an important role in the detection of tumors in humans. The second‐generation contrast agent Sonazoid has the ability of real‐time contrast imaging along with parenchymal imaging. The purposes of this study were to determine the effect and duration of Sonazoid on the changes in gray‐scale enhancement of canine spleen and to establish an appropriate protocol for contrast‐enhanced ultrasonography of canine spleen. Six healthy beagles were injected with an intravenous bolus of Sonazoid. In the spleen parenchyma, the enhancement was maintained up to 30 min after injection. Moreover, for 5–22 s after injection, gray‐scale enhancement of splenic arteries afforded arterial imaging. Perfusion of the kidney may be investigated from 3.6 s to 3.5 min after injection of Sonazoid. These results suggest that Sonazoid is applicable to canine spleen parenchymal imaging and that the optimal time for the parenchymal imaging is 7–30 min after injection. The findings of this quantitative study should prove useful in the evaluation of diffuse or focal splenic and renal diseases in dogs.
Importance of Baseline Potency Rate Assessment of Men Diagnosed with Clinically Localized Prostate Cancer Prior to Radical Prostatectomy
Authors: Salomon Georg , Isbarn Hendrik , Budaeus Lars , Schlomm Thorsten , Briganti Alberto , Steuber Thomas , Heinzer Hans , Haese Alexander , Graefen Markus , Karakiewicz Pierre I , Huland Hartwig , Chun Felix
Published: December 2008

Introduction

Erectile dysfunction (ED) is a common, and multifactorial medical problem with significant impact on quality of life. Knowledge about baseline potency is highly important in men undergoing treatment for prostate cancer (PCa) as it might influence judgments about impact of treatment and thereby treatment decisions.

Aims

To analyze the baseline potency rate of men with clinically localized PCa prior to radical prostatectomy (RP). Furthermore, it was of interest to identify comorbid factors of preoperative ED.

Main Outcome Measure

Preavalence of preoperative ED and association between comorbidities and ED in men prior to RP in bi- and multivariable logistic regression analyses.

Methods

Retrospective analysis of a large single center cohort of 1,330 evaluable PCa patients who were preoperatively assessed with the abridged 5-item version of the International Index of Erectile Function (IIEF) also described as Sexual Health Inventory for Men. Baseline potency and comorbidity rates, and their distribution were described. The risk of baseline ED associated with age, body mass index (BMI), the presence of hyperlipoproteinemia (HLP), non-insulin-dependent diabetes mellitus (NIDDM), hypertension, and depression were analyzed in bi- and multivariable logistic regression analyses.

Results

Using the IIEF-5 cutoff value of 21, 48% demonstrated some degree of ED. Severe, moderate, mild to moderate, mild, and no ED was observed in 9.2, 4.0, 10.2, 24.7, and 52% respectively. In univariable analyses, ED significantly increased according to increasing age, BMI, presence of HLP, hypertension, NIDDM, and depression (P ≤ 0.045). In multivariable analysis, age, BMI, NIDDM, and depression represented independent risk factors of baseline ED (all P ≤ 0.005).

Conclusions

It is important to note that one in two men diagnosed with a clinically localized PCa experiences some degree of baseline ED of which 23.4% are moderate to severe prior to local therapy. Age, BMI, NIDDM, and presence of depression represent important independent risk factors of baseline ED.
The Genetics and Epidemiology of Female Sexual Dysfunction: A Review
Authors: Burri Andrea V. , Cherkas Lynn M. , Spector Tim D.
Published: December 2008

Introduction

Female sexual dysfunction (FSD) is an often underestimated and common problem with serious effects on women’s quality of life. Despite a high overall prevalence in the female population—exceeding that of male sexual dysfunction—until recently, little research has focused on this area. In contrast to the successful advances of genetic research in a wide variety of human diseases, genetic exploration in FSD lags far behind.

Aim

The aim of this review is to acquaint the reader with the current behavioral and molecular genetic research in the field of FSD.

Methods

Because of the heterogeneity of the included studies, we are providing a nonsystematic review.

Results

Recent epidemiological and candidate gene studies have suggested a strong genetic influence on female sexual functioning. While these findings provide a clear rationale for more genetic research in the field, they need to be replicated on a much larger scale to be definitive.

Conclusions

Successful identification of biomarkers and novel genes underlying FSD should improve the diagnosis, identification, and treatment of different subgroups. Future pharmacotherapeutic approaches to FSD will benefit from novel targets and the concept that individual variations have a genetic component may help destigmatize our views of sexual problems.
An Exploration of the Relationship Between Depressive Symptoms and Cortisol Rhythms in Colorado Ranchers
Authors: Schulze Emily , Laudenslager Mark , Coussons‐Read Mary
Published: December 2008

ABSTRACT: 
Context: Although the effects of stress on health have been studied in numerous urban‐dwelling populations, fewer studies have addressed these effects in rural populations, such as farmers and ranchers. Purpose: The present study focuses on seasonal levels of depressed affect and perceived stress in Western Colorado ranchers, and how those phenomena related to their levels of cortisol. Methods: Twenty‐one (21) ranchers, who were permittees on the Colorado Grand Mesa, completed the study. Participants identified 2‐week time periods during the year representing relative high, medium, and low stress. During each period, participants took saliva samples, rated stress levels, and completed a daily health diary. In addition, the Beck Depression Inventory (BDI‐II), the perceived stress scale (PSS), and a life events scale (LES) were administered. Results: Results showed a strong relationship between BDI‐II and PSS scores (r = 0.748, P < .01). The decreased daytime cortisol decline supports the notion that the hypothalamic‐pituitary‐adrenal (HPA) axis negative feedback loop is disrupted in chronic stress and depression, thus resulting in chronically elevated cortisol levels. Conclusion: This study supports the relationship between stress, depression, and HPA dysregulation in ranchers.
Malpractice Burden, Rural Location, and Discontinuation of Obstetric Care: A Study of Obstetric Providers in Michigan
Authors: Xu Xiao , Siefert Kristine A. , Jacobson Peter D. , Lori Jody R. , Gueorguieva Iana , Ransom Scott B.
Published: December 2008

ABSTRACT: 
Context: It has long been a concern that professional liability problems disproportionately affect the delivery of obstetrical services to women living in rural areas. Michigan, a state with a large number of rural communities, is considered to be at risk for a medical liability crisis. Purpose: This study examined whether higher malpractice burden on obstetric providers was associated with an increased likelihood of discontinuing obstetric care and whether there were rural‐urban differences in the relationship. Methods: Data on 500 obstetrician‐gynecologists and family physicians who had provided obstetric care at some point in their career (either currently or previously) were obtained from a statewide survey in Michigan. Statistical tests and multivariate regression analyses were performed to examine the interrelationship among malpractice burden, rural location, and discontinuation of obstetric care. Findings: After adjusting for other factors that might influence a physician's decision about whether to stop obstetric care, our results showed no significant impact of malpractice burden on physicians’ likelihood to discontinue obstetric care. Rural‐urban location of the practice did not modify the nature of this relationship. However, family physicians in rural Michigan had a nearly 4‐fold higher likelihood of withdrawing obstetric care when compared with urban family physicians. Conclusions: The higher likelihood of rural family physicians to discontinue obstetric care should be carefully weighed in future interventions to preserve obstetric care supply. More research is needed to better understand the practice environment of rural family physicians and the reasons for their withdrawal from obstetric care.
Predisposing and Enabling Factors Associated with Mammography Use Among Hispanic and Non‐Hispanic White Women Living in a Rural Area
Authors: Tejeda Silvia , Thompson Beti , Coronado Gloria D. , Martin Diane P. , Heagerty Patrick J.
Published: December 2008

ABSTRACT: 
Context: Women who do not receive regular mammograms are more likely than others to have breast cancer diagnosed at an advanced stage. Purpose: To examine predisposing and enabling factors associated with mammography use among Hispanic and non‐Hispanic White women. Methods: Baseline data were used from a larger study on cancer prevention in rural Washington state. In a sample of 20 communities, 537 women formed the sample for this study. The main outcomes were ever having had a mammogram and having had a mammogram within the past 2 years. Findings: Reporting ever having had a mammogram was inversely associated with lack of health insurance (OR = 0.37, 95% CI: 0.16‐0.84), ages under 50 years (OR = 0.23, 95% CI: 0.12‐0.45), high cost of exams (OR = 0.48, 95% CI: 0.27‐0.87), and lack of mammography knowledge (OR = 0.16, 95% CI: 0.07‐0.37), while increasing education levels were positively associated (OR = 1.72, 95% CI: 1.09‐2.70). Reporting mammography use within the past 2 years was inversely associated with ages under 50 years (OR = 0.49, 95% CI: 0.27‐0.88) and over 70 years (OR = 0.47, 95% CI: 0.24‐0.94), lack of health insurance (OR = 0.23, 95% CI: 0.10‐0.50), and high cost of exams (OR = 0.55, 95% CI: 0.35‐0.87). Conclusions: Continued resources and programs for cancer screening are needed to improve mammography participation among women without health insurance or low levels of education.
Driving standards in tracheostomy care: a preliminary communication of the St Mary’s ENT‐led multi disciplinary team approach
Authors: Arora A. , Hettige R. , Ifeacho S. , Narula A.
Published: December 2008

Objectives:  To assess tracheostomy care and improve standards following the introduction of an ENT‐led multidisciplinary tracheostomy ward round service.

Design:  Prospective third cycle audit.

Setting:  Tertiary academic London hospital serving an inner city population of multi‐ethnic background (St Mary’s Hospital, Paddington, London).

Participants:  Patients with a tracheostomy discharged from ITU to general wards.

Implemented actions:  • Establishment of an ENT‐led Tracheostomy Multidisciplinary Team (TMDT).

• Weekly TMDT ward round to manage patients with a tracheostomy.

• ENT‐led educational and training sessions for allied healthcare professionals.

Main outcome measures:  Compliance with local tracheostomy care guidelines (St Mary’s tracheostomy care bundle) and time to tracheostomy tube decannulation.

Results:  Preliminary results of 10 patients show improved compliance with tracheostomy care guidelines, established in 2004, rising to 94%. Average time to decannulation was significantly reduced from 21 to 5 days (P‐value = 0.0005, Mann Whitney Wilcoxon Test). The mean total tracheostomy time was reduced from 34 to 24 days although this was not statistically significant (P‐value = 0.13, Mann Whitney Wilcoxon Test).

Conclusions:  The introduction of regular ENT‐led multidisciplinary input for patients with a tracheostomy significantly improved compliance with nursing care standards. There was also a reduction in the total length of time tracheostomy tubes remain in situ, with time to decannulation significantly reduced.
The effect of hand dominance on recurrent idiopathic paediatric epistaxis1
Authors: Joice P. , Ross P. , Robertson G. , White P.
Published: December 2008

Objectives:  No published data exists to support the belief that nose picking contributes to recurrent idiopathic paediatric epistaxis. If nose picking is implicated then there may be a higher incidence of epistaxis on the side of the dominant hand. The objective of the study was to determine whether nose picking has a significant role in paediatric epistaxis by comparing hand dominance and side of epistaxis.

Design and setting:  A prospective, consecutive cohort of new epistaxis referrals to a tertiary paediatric centre over a 14‐month period were assessed for hand dominance and reported side of the epistaxis. The presence of septal excoriation, crusting and prominent blood vessels was also recorded.

Participants:  One hundred and forty‐eight new epistaxis referrals.

Main outcome measures:  Dominant hand, side of epistaxis history and side of positive examination findings.

Results:  No statistically significant association between hand dominance and either epistaxis history or examination findings was identified. A statistically significant association between epistaxis history and examination findings was identified P < 0.001, K = 0.614, SE 0.571.

Conclusions:  The study does not provide evidence to support the belief that paediatric epistaxis is influenced by nose picking. The study provides evidence that patients’ epistaxis history and positive examination findings are a consistent marker of previous epistaxis.