bluuebunny/crossref_metadata_2025 huggingface dataset:
Usefulness of Transesophageal Echocardiography in the Isolation of Pulmonary Veins in the Treatment of Atrial Fibrillation
Authors: CHAMPAGNE JEAN , ECHAHIDI NAJMEDDINE , PHILIPPON FRANÇOIS , ST‐PIERRE ANDRÉ , MOLIN FRANCK , BLIER LOUIS , GILBERT MARCEL , VILLENEUVE JACQUES , MOHTY DANIA , O'HARA GILLES
Published: January 2007

Background: New imaging strategies for atrial fibrillation (AF) ablation should enhance the safety of this technique. The role of transesophageal echocardiography (TEE) in this setting has not been prospectively evaluated.

Methods: Under general anesthesia, 85 patients underwent TEE‐guided AF ablation. A hybrid technique was performed with circular pulmonary veins (PV) lesions and antrum and ostial electrical isolation guided by TEE. TEE excluded left atrial (LA) thrombus, guided transseptal puncture and catheter positioning, and helped to identify PV ostia and their velocities. The TEE probe localized the esophagus, its temperature (T°) and micro bubbles formation.

Results: Overall, one patient had a LA clot. The esophagus was located close to left PV in 38%, the right PV in 28%, midline in 17% and with an oblique course in 17% of patients. Right and left superior PV velocities were detected in 100%, left inferior PV in 88% and right inferior PV in 82% of patients. Microbubbles were detected in 9 patients (11%). Elevation of TEE T° occurred in 14 patients (16%) and was regularly observed when lesions were applied over the TEE probe shadow, in close proximity to the posterior wall. Two major complications (1 tamponade, 1 PV laceration) occurred and were detected early by TEE.

Conclusions: TEE offers advantages compared to a map‐guided only approach. It is a reliable tool to assess esophagus T° and localization, guide transseptal puncture, delineate the PV ostia, and monitor complications.
Incidence and Characteristics of Appropriate and Inappropriate Therapies in Recipients of ICD Implanted for Primary Prevention of Sudden Cardiac Death
Authors: KREUZ JENS , BALTA OSMAN , LILIEGREN NORA , MELLERT FRITZ , ESMAILZADEH BAHMAN , NICKENIG GEORG , SCHWAB JÖRG OTTO
Published: January 2007

Background: We evaluated the number of appropriate and inappropriate therapies for ventricular tachyarrhythmias and trigger mechanisms in 55 MADIT II (MII)‐like (group 1) and 86 SCD‐HeFT‐like (group 2) patients.

Methods and Results: We analyzed 399 appropriate episodes in 31 patients with implantable cardioverter defibrillators (ICD) implanted according to the MII trial indications, and 502 appropriate episodes in 47 patients matching the SCD‐HeFT trial criteria (mean follow‐up in both groups = 33 ± 19 months). In group 1, 39 treated episodes were inappropriate (9% of all episodes), while in group 2, 76 episodes were treated inappropriately (15% of all episodes). At least one episode of inappropriate ICD therapy was recorded in 18% of patients in group 1 (n = 10) and in 22% of patients in group 2 (n = 19).

Conclusions: Our study supports the implantation of ICD as primary prevention in patients who are at risk of sudden cardiac death, although the proportion of inappropriate ICD interventions remains high.
Prevention of Inappropriate Shocks in ICD Recipients: A Review of 10,000 Tachycardia Episodes
Authors: ANSELME FRÉDÉRIC , MLETZKO RALPH , BOWES ROBERT , MABO PHILIPPE , SADOUL NICOLAS , SCHOELS WOLFGANG , SEIDL KARLHEINZ , SCHWAB JOERG , ISCOLO NICOLAS , NITZSCHÉ RÉMI
Published: January 2007

Background: The efficacy of dual‐chamber ICD arrhythmia classification algorithms is crucial to prevent inappropriate shocks. We report our experience from a meta‐analysis of five prospective clinical studies with inclusion phases ranging between 1997 and 2003.

Methods: Dual‐chamber ICD using standard dual‐chamber arrhythmia classification algorithms were implanted in 802 patients (mean age = 64 ± 11 years, 88% men) in 74 medical centers. The ICD indication was secondary prevention in 95% of patients. Supraventricular tachyarrhythmias (SVT) were previously documented in 26% of patients. All spontaneous tachyarrhythmic events documented by the device memories were analyzed by a adjudicating committee. The episodes lasting >12 seconds and/or treated by the ICD were analyzed.

Results: Over a mean follow‐up of 302 ± 113 days, 9,690 events were reported. Mean heart rate at the time of events was 131 ± 45 bpm (100–430). Events were classified as oversensing in 1.4%, sinus tachycardia (ST) in 66%, SVT in 13%, slow (<150 bpm) ventricular tachycardia (VT) in 8.7%, and VT or ventricular fibrillation (VF) in 10.3%. The sensitivity of slow VT detection was 94%, and of VT/VF detection 99.3%. The specificity of sinus rhythm/ST/SVT recognition was 94%, positive predictive value 79.3%, and negative predictive value 99.2%. A total of 1,918 episodes were treated in 330 patients: 1,472 appropriately in 213, and 446 inappropriately in 117 (15% of the overall population) patients. Only 62 episodes were inappropriately treated by shocks in 40 patients, representing 5% of the overall population.

Conclusions: In this conventional ICD population, the overall specificity of standard dual‐chamber arrhythmia detection settings reached 94%. This feature allows efficient detection of fast as well as slow VT events with a very low rate of inappropriate shocks.
Outcomes of Elderly Recipients of Implantable Cardioverter Defibrillators
Authors: GRIMM WOLFRAM , STULA ASTRID , SHARKOVA JULIA , ALTER PETER , MAISCH BERNHARD
Published: January 2007

Aims of the Study: To examine the patterns of use, complication rates, and survival in elderly recipients of implantable cardioverter defibrillators (ICD).

Methods and Results: We followed 500 consecutive patients included in the Marburg Defibrillator database for 48±39 months. There were 40 patients (8%) ≥75 and 460 (92%) <75 years of age at the time of implant. The 5‐year Kaplan‐Meier estimate for appropriate treatment of VT or VF by ICD was 49% among patients <75‐ versus 57% among patients ≥75‐years‐old (P = 0.17). The 5‐year sudden death rate was similarly low in both groups of patients (2% versus 3%). The 5‐year overall mortality rate was significantly higher in patients ≥75 than in patients <75 years of age (55% versus 21%, P = 0.001), due to a higher mortality from heart failure (HF). All procedure‐related, lead‐related, and pulse generator‐related complications were similar in both patient groups (23% versus 25%).

Conclusions: ICD therapy was equally effective in patients ≥75 and patients <75 years of age in the prevention of sudden cardiac death. While the complication rates were similar in both age groups, the long‐term mortality was considerably higher in elderly patients, due to a higher mortality from HF. The current ICD therapy guidelines appear applicable to elderly patients who are otherwise medically stable and without advanced HF.
“Tuned” Defibrillation Waveforms Outperform 50/50% Tilt Defibrillation Waveforms: A Randomized Multi‐Center Study
Authors: NATARAJAN SENTHIL , HENTHORN RICHARD , BURROUGHS JEFFERSON , ESBERG DOUGLAS , ZWEIBEL STEVEN , ROSS TERENCE , KROLL MARK , GIANOLA DON , OZA ASHISH
Published: January 2007

Introduction: A superior performance of a tuned waveform based on duration using an assumed cardiac membrane time constant of 3.5 ms and of a 50/50% tilt waveform over a standard 65/65% tilt waveform has been documented before. However, there has been no direct comparison of the tuned versus the 50/50% tilt waveforms.

Methods: In 34 patients, defibrillation thresholds (DFTs) for tuned versus 50/50% tilt waveforms in a random order were measured by using the optimized binary search method. High voltage lead impedance was measured and used to select the pulse widths for tuned and 50/50% tilt defibrillation waveforms.

Results: Delivered energy (7.3 ± 4.6 J vs 8.7 ± 5.3 J, P = 0.01), stored energy (8.2 ± 5.1 J vs 9.7 ± 5.6 J, P = 0.01), and delivered voltage (405.9 ± 121.7 V vs 445.0 ± 122.6 V, P = 0.008) were significantly lower for the tuned than for the 50/50% tilt waveform. In four patients with DFT ≥15 J, the tuned waveform lowered the mean energy DFT by 2.8 J and mean voltage DFT by 45 V. For all patients, the mean peak delivered energy DFT was reduced from 29 J to 22 J (24% decrease). Multiple regression analysis showed that a left ventricular ejection fraction <20% is a significant predictor of this advantage.

Conclusion: Energy and voltage DFTs are lowered with an implantable cardioverter defibrillator that uses a tuned waveform compared to a standard 50% tilt biphasic waveform.
Noninvasive Classification of Ventricular Preexcitation with Unshielded Magnetocardiography and Transesophageal Atrial Pacing and Follow‐Up
Authors: BRISINDA DONATELLA , FENICI RICCARDO
Published: January 2007

Background: Ventricular preexcitation (VPx) is usually localized noninvasively by means of electrocardiogram (ECG) algorithms, which vary in their concordance levels. Contactless magnetocardiography (MCG) has been used as an alternate 3‐dimensional (3D) method of accessory pathways (AP) localization. The sensitivity of MCG can be increased for preoperative evaluations and planning of ablation procedures by combining it with transesophageal pacing (TEP) and electrophysiological (EP) studies. This study compared the accuracy of VPx localization with MCG with ECG algorithms, and examined the increment in diagnostic accuracy achievable with TEP.

Methods: Multisite mapping from the anterior chest wall was performed with a 36‐channel MCG system. TEP allowed the evaluation of anterograde conduction properties and inducibility of arrhythmias. The reproducibility of the test and follow‐up was examined in 88 patients with Wolff–Parkinson–White (WPW) syndrome. The accuracy of MCG localization was reevaluated during pacing‐induced maximal VPx in 36 patients in whom, during MCG, the degree of VPx was highest during TEP. The gold standard for validation was effective ablation of the AP.

Results: The MCG classification of VPx was accurate in 94% of AP, versus 64% and 67% with ECG, during sinus rhythm and during pacing‐induced maximal VPx, respectively. In 4.5% of cases with unclear ECG localization, MCG suggested a complex septal VPx. In all patients with successful ablations, the 3D MCG localization of the AP corresponded to the ablation site.

Conclusions: MCG was more accurate than ECG for the classification of VPx and provided additional information in the non‐invasive EP assessment of patients with WPW syndrome.
High Prevalence of False Chordae Tendinae in Patients Without Left Ventricular Tachycardia
Authors: GUALANO SARAH K. , BOLLING STEVEN F. , GORDON DAVID , WILSON ALLECIA , BACH DAVID S.
Published: January 2007

Background: Left ventricular (LV) false chordae tendinae (false chords) have been implicated as a source of idiopathic left (IL) ventricular tachycardia (VT). However, it is unknown whether pretest bias contributes to an apparent association with disease. The purpose of this study was to determine the prevalence of false chords on direct inspection of the LV endocardium.

Methods: In a prospective series, 75 hearts were examined to identify and characterize false chords, including 20 specimens examined at autopsy and 55 consecutive patients undergoing mitral valve surgery. Medical records were reviewed for history of VT, including ILVT.

Results: Of 75 patients whose hearts were studied, none had a history of ILVT and only 5 had a history of any VT. False chords were present in 34 of 75 (45%) hearts, including 13 of 20 (65%) at postmortem and 21 of 55 (38%) examined at surgery (P = 0.07). The prevalence of false chords was not different among patients with (3 of 5 [60%]) versus those without (31 of 70 [44% p = 0.65]) a history of VT (P = 0.65).

Conclusions: In this prospective anatomic series, the prevalence of LV false chords on autopsy and surgical inspection was approximately 45% among patients without ILVT. Previously reported associations of false chords with ILVT likely underestimated the prevalence of false chords in a normal population.
Low Doses of Intracoronary Enalaprilat Suppress Reperfusion‐Associated Ventricular Arrhythmias after Primary Percutaneous Coronary Interventions for Acute Myocardial Infarction
Authors: BONNEMEIER HENDRIK , SCHÄFER ULRICH , ORTAK JASMIN , KURZ THOMAS , KATUS HUGO A. , RICHARDT GERT , SCHUNKERT HERIBERT
Published: January 2007

Background: In the era of early reperfusion therapy, life‐threatening ventricular arrhythmias (VA) remain common after recanalization of an occluded coronary artery. Experimental studies reported that angiotensin‐converting (ACE) inhibitors suppress reperfusion‐induced VA. However, whether ACE inhibitors lower the incidence of reperfusion clinical VA is unknown. We examined the effects of low doses of intracoronary (i.c.) enalaprilat (EN) as an adjunct to direct percutaneous coronary interventions (PCI) on reperfusion VA in the acute phase of myocardial infarction (MI).

Methods: We randomly assigned 22 patients with a first acute MI, who underwent successful direct PCI, to EN, 50 μg, i.c., or placebo (PL), administered immediately after reperfusion. VA were manually edited and counted from 24‐hour Holter recordings begun upon hospital admission.

Results: There were no significant between‐groups differences in clinical characteristics. Mean RR interval before and after PCI, and the incidence of VA before PCI were similar in both groups. After PCI the incidence of reperfusion‐induced VA was significantly lower in the EN‐treated group (VPB/h: PL 29.9 ± 12 vs EN 43.2 ± 42, P < 0.05; couplets/h: EN 0.9 ± 0.7 vs PL 4.1 ± 5.0, P < 0.01; triplets/h: EN 0.3 ± 0.2 vs PL 1.2 ± 1.5, P < 0.05; ventricular tachycardia/h: EN 0.3 ± 0.1 vs PL 0.8 ± 0.5, P < 0.01).

Conclusions: Compared with PL, i.c. EN significantly lowered the incidence of reperfusion‐associated VA. This previously unrecognized antiarrhythmic effect might be an important therapeutic benefit conferred by ACE inhibitors, beyond limitation of infarct size.
Microvolt T‐Wave Alternans During Atrial and Ventricular Pacing
Authors: SHALABY ALAA A. , VOIGT ANDREW , EL‐SAED AIMAN , MAINS MARTIN , SHUSTERMAN VLADIMIR
Published: January 2007

Introduction: Assessment of microvolt T‐wave alternans (MTWA) by the spectral analysis (SA) method requires the heart rate to be stable within a certain range. This can be achieved by ventricular pacing (VP). We compared MTWA during short‐term VP versus atrial pacing (AP).

Methods: Patients presenting for evaluation of risk of sudden cardiac death underwent an invasive electrophysiologic study. The concordance of results of MTWA‐VP with MTWA‐AP was evaluated, as well as the specificity, sensitivity, negative, and positive predictive values of MTWA‐VP versus MTWA‐AP. The maximum recorded amplitude of MTWA (MValt) in concordant positive results, as well as noise levels in all, were compared in both pacing modes.

Results: We studied 42 consecutive patients, of whom 31 completed both tests (32 by AP, 40 by VP). Compared to AP, VP—MTWA SA had a sensitivity of 93%, specificity of 71%, negative predictive value of 92%, and positive predictive value of 72%. The results were concordant in 25 patients (80%, κ= 0.62, P < 0.001). The noise level was significantly higher during VP than AP (1.4 ± 0.8 vs 1± 0.8, P< 0.01), and there was a trend toward a higher amplitude of TWA by VP (10.7 ± 5.3 vs 7.8 ± 3.9, P = 0.058).

Conclusions: MTWA SA is more likely to be completed during VP than AP. Overall there was concordance between both tests. VP generates higher amplitudes and noise, and a higher percentage of nonnegative results.
Impact of Diabetes on QT Dynamicity in Patients With and Without Myocardial Infarction: The KORA Family Heart Study
Authors: LIEB WOLFGANG , VOSS CHRISTIAN , ORTAK JASMIN , BARANTKE MELANIE , HENGSTENBERG CHRISTIAN , LOEWEL HANNELORE , HOLMER STEPHAN , ERDMANN JEANETTE , SCHUNKERT HERIBERT , BONNEMEIER HENDRIK
Published: January 2007

Introduction: Patients with diabetes mellitus (DM) have an unfavorable prognosis after myocardial infarction (MI), partially due to a higher risk of sudden cardiac death (SCD). QT dynamicity is an independent predictor of SCD in post‐MI patients. However, the effects of diabetes on QT dynamicity in patients with MI have not been described.

Methods: We studied 468 survivors of MI (67 with DM) from the population‐based MONICA registry (KORA Family Heart Study), Augsburg, Germany, by standardized questionnaire, anthropometry, electrocardiogram (ECG), 30‐minute‐Holter‐ECG‐recordings and echocardiography. In addition, 422 siblings without prior MI (22 with DM) were studied by the same protocol.

Results: Among post‐MI patients, the QT/RR slope was significantly steeper in diabetics than in nondiabetics (0.096 ± 0.057 vs 0.077 ± 0.045; P = 0.002). Likewise, among siblings without MI, the QT/RR slope was steeper in diabetics than in nondiabetics (0.104 ± 0.053 vs 0.080 ± 0.042; P = 0.008). The association of DM with steeper QT/RR slope remained significant in multivariate models in post‐MI patients (β: −0.14; P = 0.004) as well as in individuals without MI (β: −0.10; P = 0.047).

Conclusions: In a large population of survivors of MI and unaffected siblings, patients and siblings presenting with DM exhibited an abnormal QT rate‐dependence, compared with individuals without DM in both groups. Thus, diabetes itself may be a major determinant of ventricular arrhythmias, independently of a previous MI. These observations might in part explain the higher incidence of sudden cardiac death and ventricular arrhythmias in patients with DM.
Abnormal Nocturnal Heart Rate Variability and QT Dynamics in Patients with Brugada Syndrome
Authors: PIERRE BERTRAND , BABUTY DOMINIQUE , PORET PHILIPPE , GIRAUDEAU CEDRIC , MARIE OLIVIER , COSNAY PIERRE , FAUCHIER LAURENT
Published: January 2007

Background: In Brugada syndrome (BSY), most of the ventricular arrhythmic events are nocturnal, suggesting an influence of the autonomic nervous system.

Methods: In 46 patients (mean age = 41 ± 14 years, 43 men) with electrocardiograms (ECG) consistent with BSY and structurally normal hearts, we measured heart rate variability (HRV) and QT dynamics (QT/RR slopes) on 24‐hour ambulatory ECG. Type 1 BSY‐ECG was spontaneous in 23 (50%) and induced in 23 patients.

Results: History of syncope was present in 23 patients (50%). Programmed ventricular stimulation induced ventricular tachyarrhythmias (VTA) in 13 patients (28%). A single patient developed ventricular tachycardia during a mean follow‐up of 34 months. Compared to a control group matched for age and sex, HRV was decreased over 24 hours and during nighttime in patients with BSY (SDNN 122 ± 44 vs 93 ± 36 ms, P = 0.0008 and SDANN 88 ± 39 vs 54 ± 24 ms, P < 0.0001). QTend /RR slopes were decreased over 24 hours in patients with BSY (0.159 ± 0.05 vs 0.127 ± 0.05, P = 0.003) and particularly at night (0.123 ± 0.04 vs 0.089 ± 0.04, P = 0.0001). QTend /RR slopes were significantly decreased during nighttime in patients with spontaneous versus provoked BSY‐ECG patterns. By contrast, HRV and QT/RR slopes were similar in symptomatic and asymptomatic patients, whether VTA were induced or not.

Conclusions: Patients with a BSY‐ECG pattern had lower HRV and QT/RR slopes than control subjects during nighttime. High‐risk patients with spontaneous BSY‐ECG patterns had the lowest nocturnal QTend/RR slopes. These unique repolarization dynamics might be related to the frequent nocturnal occurrence of VTA in BSY.
Effects of Atrial Tachypacing on Symptoms and Blood Pressure in Severe Orthostatic Hypotension
Authors: KOHNO RITSUKO , ABE HARUHIKO , OGINOSAWA YASUSHI , NAGATOMO TOSHIHISA , OTSUJI YUTAKA
Published: January 2007

The treatment of severe orthostatic hypotension (OH) is currently unsatisfactory and usually includes various pharmaceuticals to expand the blood volume and promote peripheral vasoconstriction. This study examined the short‐ and intermediate‐term effects of atrial tachypacing (ATP) in patients with severe OH. We implanted dual chamber pacemakers in five patients (mean age 64 ± 7 years; four men), presenting with drug refractory, recurrent syncope, and OH due to panautonomic failure with severe chronotropic incompetence and absence of rate acceleration upon assuming the upright posture. The blood pressure (BP) was measured in the supine and passive upright postures, during sinus rhythm, and during atrial pacing at 90, 100, and 110 ppm, at 1 week and at discharge and/or 3 months after pacemaker implantation. Alleviation of symptoms and a delay in the fall in upright BP were observed in a single patient at 1 week, while at discharge and/or 3 months, all patients were markedly improved. The mean fall in systolic/diastolic BP between supine and upright position decreased from 73 ± 17/46 ± 13 mmHg before, to 56 ± 27/41 ± 30 mmHg during ATP. Although these changes did not reach statistical significance, the time required for the fall in BP lengthened significantly from 2.1 ± 0.2 minutes during sinus rhythm to 9.3 ± 1.5 minutes during ATP (P < 0.001).

Conclusions: At discharge and/or 3 months of follow‐up, ATP conferred beneficial effects on orthostatic BP and alleviated symptoms in patients with severe OH. The short‐term effects of ATP did not reflect its longer‐term effects in four of the five patients.
Difference in Autonomic Nervous Control between Ventricular Septal Defect and Atrial Septal Defect Based on Heart Rate Variability
Authors: HATA TADAYOSHI , MANO SEIKO , KUSUKI MASAFUMI , MATSUURA HIDEAKI , MIYATA MASAFUMI , YAMAZAKI TOSHIO , NAGAOKA SYUNJI
Published: January 2007

Background: We hypothesized that patients with atrial (ASD) and ventricular septal defects (VSD) have similarly reduced heart rate variability (HRV) since both defects cause similar increases in pulmonary blood flow and right ventricular filling pressure. We examined the correlation between HRV and respiratory frequency (RSA) characteristics and left‐to‐right shunt ratio (Qp/Qs) measured by Doppler echocardiography.

Methods: The study included 83 patients with diagnoses of ASD (n = 43) or VSD (n = 40). The electrocardiogram and respiratory waves were recorded during Doppler echocardiography test, and HRV was measured to calculate the low frequency (LF), high frequency (HF), total frequency (TF), and RSA components, and the LF/HF, RSA/TF, and LF/RSA ratios. Qp/Qs was calculated from Doppler echocardiography and its relationship with HRV parameters was examined by multivariate analysis.

Results: There was a positive correlation between Qp/Qs and LF/RSA in the ASD group, and a negative correlation in the VSD group. In contrast, Qp/Qs correlated negatively with RSA/TF in the ASD group, and positively in the VSD group.

Conclusion: Different effects of respiratory vagal activity on HRV were observed in patients with ASD versus VSD.
Diffusion and spillover of new technology: a heterogeneous‐agent model for cassava in West Africa
Authors: Johnson Michael E. , Masters William A. , Preckel Paul V.
Published: January 2007

Understanding what determines the geographic spread of innovations can help guide the funding and implementation of research and extension programs. Our approach uses household survey data as model parameters, to simulate behavior across the entire surveyed population and avoid the aggregation bias associated with representative‐farm models. Such a “heterogeneous agent” approach allows us to infer the distribution of a technology's impacts across one set of households, and predict the potential for spreading to another set that shares similar characteristics with respect to natural resource endowments and farming systems. We apply the technique to new cassava varieties in West Africa, finding a strongly poverty‐alleviating impact, with substantial spillover potential from Nigeria to neighboring countries.
Incorporating nutrients into meat demand analysis using household budgets data
Authors: Angulo Ana María , Gil José María
Published: January 2007

The objective of this article is to analyze the Spanish demand for meat, taking into account the consumer's concern about the relationship between food diet and health. This concern is forcing food demand analysts to assume that consumer utility is a function of nutrients instead of simply the food products themselves. Nevertheless, these utility function arguments are not produced in the marketplace but rather at home. As a consequence, in this article household production theory is followed in order to analyze Spanish demand for meat using the Quarterly National Expenditure Survey for 1999. Demands for several meat products (the input in the model) are derived from the translog cost function. Censored regression models are used in the estimation process, since many zero responses are reported. Five broad categories, eight nutrients, and the most relevant socioeconomic variables are considered. Finally, a set of elasticities is calculated with respect to all the variables included in the analysis.
Effective dimensionality and factors affecting crop‐livestock integration in West African savannas: a combination of principal component analysis and Tobit approaches
Authors: Manyong V. M. , Okike I. , Williams T. O.
Published: January 2007

Crop‐livestock integration (CLI) to improve natural resource management for increased productivity is evolving in Nigeria and West Africa. Processes in the evolution and factors that influence it still need to be well understood. This article proposes and tests a new framework for measuring the multiple dimensionality of CLI. The framework derives a CLI index using the principal components of its most common single measures; it develops geographic information systems (GIS)‐based village‐level ecological and market factors; and it estimates parameters of factors affecting CLI using the derived index as the dependent variable in a Tobit model. The framework is tested using empirical data from 634 farm households in 11 geo‐referenced villages in the Sudan savanna (SS) and northern Guinea savanna (NGS), Nigeria. Along a north–south (SS to NGS) axis, CLI initially increases, peaking around 11.2°N, and then declines. This latitude probably identifies the boundary below which disease challenge constrains traditional livestock production and CLI. This polynomial pattern of CLI is contrary to an expected linear increase along lines of perceived potentials for rain‐fed crop production. Household resources, GIS‐derived village‐level market factors, and institutional factors also significantly affect CLI. Ecological and institutional factors have most impact on the probability of adoption and use intensities of CLI. The incorporation of GIS‐derived market factors with household and institutional variables in an econometric model offers new opportunities for assessing patterns of evolution of CLI, comparing results across sites, and targeting recommendation domains objectively. A comparison with results from more common methods of running independent models for individual indicators of CLI shows that this new framework is an effective way of reducing the multiple dimensionality of CLI to gain quicker, well‐focused knowledge of the processes of agricultural intensification.
Demand for rural tourism: the effects of quality and information
Authors: Skuras Dimitris , Petrou Anastasia , Clark Gordon
Published: January 2007

The development of rural tourism is regarded as a promising diversification strategy especially for lagging and mountainous areas of the European Union. Research concerning the demand and/or supply of rural tourism services has been limited within the agricultural economics domain despite the significance attached to rural tourism by various rural development policy measures and initiatives. The article examines the expenditure behavior of rural tourists within a framework of demand for composite (heterogeneous) goods. The proposed framework captures the quality of the tourism experience as the commodity's unit value, a quantifiable economic variable, examines its effects on expenditures and allows for the estimation of elasticity in prices regarding expenditure and quantity. Empirical analysis is facilitated by a survey recording the expenditure behavior of 465 tourists in two rural and lagging areas of Greece. The quality of the tourism experience is significantly and positively affected by the income, the source from which information about the trip is retrieved (Internet, newspapers as well as general press and special travel press) and by the amount of information sought by the consumer prior to the trip. In turn, the quality of the tourism experience is the major endogenous factor that positively influences expenditures for rural tourism. Further research is needed before evidence provided in this work can be used to draw policy conclusions and recommendations.
A model of shifting cultivation: can soil conservation reduce deforestation?
Authors: Takasaki Yoshito
Published: January 2007

Shifting cultivators manage soil not only by adjusting soil use on already‐cleared lands, as in continuous cultivation, but also by clearing forests to obtain new fertile soils. This study examines the crucial link between on‐farm soil conservation and deforestation in shifting cultivation by modeling forest clearing as an investment in soil for a private farmer. More generally, by doing so the study attempts to integrate deforestation and soil conservation models which have been separately developed in the literature. Our policy goal is to arrest tropical deforestation—as destruction of global commons—caused by land degradation in shifting cultivation while improving the well‐being of poor shifting cultivators. Our integrated approach enables joint policy analyses of deforestation and land degradation. Three welfare‐enhancing policies are considered. The first is agricultural and nonagricultural subsidies affecting farm and nonfarm income opportunities. The second is fiscal and tenure policies affecting discount rates. Our question is whether the link between forest clearing and soil fertility alters the outcomes of these two standard macroeconomic policies commonly found in the literature. The third policy (or program) is various soil conservation measures affecting soil regeneration and erosivity on already‐cleared lands. This article examines a very important question which has received little attention in previous theoretical works: can soil conservation reduce deforestation? This study confirms anti‐deforestation effects of the promotion of nonfarming activities—a common and often emphasized finding in previous works—among shifting cultivators. More importantly, it also demonstrates that improving various soil conservation measures not only discourages forest clearing among shifting cultivators but also tends to have greater effects on forest protection than promoting nonfarming activities. Contrarily, agricultural price subsidy or technological progress gives rise to the opposite outcome, and lowering the farmer's discount rate or improving tenure security encourages him/her to clear more forests just to accumulate soil.
Allergic contact dermatitis to hydrolyzed wheat protein in a cosmetic cream
Authors: Hann Samantha , Hughes Meirion , Stone Natalie
Published: January 2007

Hydrolyzed wheat protein is used as an additive in several cosmetic products. We present a case of contact allergy to hydrolyzed wheat protein found in a cosmetic cream and highlight this additive is a potential allergen.
Patch test results in patients with scalp dermatitis: analysis of data of the Information Network of Departments of Dermatology*
Authors: Hillen Uwe , Grabbe Stephan , Uter Wolfgang
Published: January 2007

Background:  Contact dermatitis of the scalp may develop primarily due to exposure to cosmetic products or secondarily due to application of topical medicaments on affected skin.

Objectives:  To illustrate the current spectrum of allergens in scalp dermatitis.

Patients/methods:  Data of 1320 patients recorded by the Information Network of Departments of Dermatology (IVDK) between 1993 and 2003, who were patch tested to confirm or rule out (secondary) allergic contact dermatitis of the scalp, were analysed.

Results:  Sensitization to p‐phenylenediamine, tolune‐2,5‐diamine, p‐aminophenol, 3‐aminophenol, p‐aminoazobenzene, cocamidopropyl betaine and pyrogallol was significantly more common than in the remaining IVDK patients. In 690 patients, altogether 4070 patients’ own products were patch tested. Medical products, hair tints and bleaches (HTB) and hair‐cleansing products together caused nearly 2/3 of positive patch test reactions. Among these categories, HTB showed the highest percentage of positive patch test reactions; 24 of 29 HTB‐positive patients had no positive reaction to any of the commercially available allergens.

Conclusions:  In our subgroup of patients with scalp dermatitis, constituents of hair‐colouring products were the most important allergens. As some ingredients of hair dyes are not contained in patch test series, testing of patients’ own products is an important part of diagnostic workup, as otherwise sensitizations may be missed.
Standard patch test results in patients with contact dermatitis in Israel: age and sex differences
Authors: Freireich‐Astman Michal , David Michael , Trattner Akiva
Published: January 2007

Previous studies have shown that the prevalence of specific allergens varies by geographic area, population, age and sex. The objective of the present study was to determine the relative frequency of positive reactions to different sensitizers in Israeli patients with clinically suspected contact dermatitis (CD) and to identify possible sex and age differences. A total of 943 consecutive patients were tested for CD using the European standard patch test series. The most frequent allergen was nickel sulfate followed by potassium dichromate and fragrance mix. Positive reactions to nickel sulfate were more common among women, especially those in the younger age group (younger than 40 years). Positive reactions to balsam of Peru were more common among men, especially those in the older age group (40 years or older). This study presents the result of the standard patch test in Israel with stratification according to age and sex. The findings of the present study, combined with reports on geographic/population differences in the prevalence of specific allergens in CD, indicate the need for further investigations to identify prominent local allergens for better adaptation of the standard patch test to local needs.
Contact sensitivity and atopic dermatitis: association with prognosis, a follow‐up study in 801 atopic patients
Authors: Mäkelä Leeni , Lammintausta Kaija , Kalimo Kirsti
Published: January 2007

The influence of contact sensitivities on the course of atopic dermatitis (AD) is not known. The objective of the study is to find the course of AD in atopic patients with and without contact sensitivities. A total of 801 atopic patients were studied and patch tested in 1983/84. A questionnaire focusing on the occurrence of dermatitis was sent to these patients 16 years later. During the follow up the number of symptom‐free patients increased from 36.7% to 40.7%. In patients with positive patch‐test reactions, 30.1% were symptom free in 1983/84 and 38.3% at the follow up (P= 0.001). Among those with positive patch‐test reactions to fragrance mix and/or balsam of Peru, the number of symptom‐free patients had increased the most: from 26.9% to 42.6% (P= 0.0095), and a similar tendency was seen among those with nickel allergy. The occurrence of dermatitis did not change among patients without contact sensitivities. Thus, the study concluded that contact allergy does not impair the prognosis of dermatitis in atopic patients.
Actual versus optimal utilization of radiotherapy in lung cancer: Where is the shortfall?
Authors: VINOD Shalini K , BARTON Michael B
Published: January 2007

Background:  Estimates of ideal radiotherapy utilization in lung cancer range from 61% to 74%. Actual utilization rates are lower than this. The aim of the present study was to identify those groups where there was the greatest discrepancy between actual and ideal utilization.

Methods:  The study population consisted of South‐Western Sydney Area Health Service residents who were diagnosed with lung cancer in 1993 or 1996. A clinical audit of medical records was performed to collect details on patient demographics, tumor factors, treatment details and outcome.

Results:  There were 527 patients diagnosed with lung cancer. Treatment data were available for 499 (95%) patients of which 279 (56%) received radiotherapy. Radiotherapy utilization declined with increasing age and decreasing performance status. When comparing actual with ideal utilization, the greatest shortfall in radiotherapy was seen in small cell lung cancer (55%vs 79%) followed by stage I (35%vs 50%) and IV non‐small cell lung cancer (65%vs 83%). There was under‐utilization of chest radiotherapy (79%vs 88%) and definitive radiotherapy (14%vs 50%).

Conclusions:  Definitive chest radiotherapy is underutilized in lung cancer, particularly in patients with limited stage small cell lung cancer and stage I non‐small cell lung cancer. This is partly due to non‐referral of patients but also a palliative approach by radiation oncologists. These factors have to be addressed in order to optimize survival and quality of life for lung cancer patients.
Multicenter phase II study of combination chemotherapy with capecitabine and intravenous vinorelbine in patients with pretreated metastatic breast cancer
Authors: DAVIS Alison J , BREW Sue , GEBSKI Val J , LEWIS Craig R , MOYLAN Eugene , PARNIS Francis X , ACKLAND Stephen P
Published: January 2007

Background:  Capecitabine and i.v. vinorelbine are both active in metastatic breast cancer with non‐overlapping toxicities. This study examined the efficacy and safety of the combination of these agents in patients with pretreated metastatic breast cancer.

Methods:  Patients previously treated for breast cancer, maximum of one prior metastatic regimen, received capecitabine 1000 mg/m2 b.d. for days 1–14 and vinorelbine 25 mg/m2 i.v. days 1 and 8 every 21 days. All patients had measurable disease and adequate baseline organ function. The primary endpoint was response and secondary endpoints time to progression, duration of response, survival and safety.

Results:  Twenty‐two patients (median age 56 years) received a median of six cycles. All patients had received anthracyclines and 64% taxanes. Objective responses were seen in 7/21 (33%, 95% confidence interval [CI] 18–57%), with two complete responses; stable disease was seen in 5/21 (24%, 95% CI 8–42%). Median duration of response was 6.9 months (95% CI 4.7–13.1), time to progression was 5.8 months (95% CI 2.8–6.8) and survival was 13.5 months (95% CI 6.9–19.9). The median dose intensity of vinorelbine was 75% of the intended dose and of capecitabine 85% of intended dose. The main toxicity was myelosuppression including 16 episodes of G3–4 neutropenia in 11 patients (50%). Other toxicities were generally mild to moderate.

Conclusion:  The combination of capecitabine and i.v. vinorelbine is active and well tolerated in patients with pretreated metastatic breast cancer. The recent availability of oral vinorelbine provides an opportunity to explore a fully oral combination.
Associations of Spiders of the GenusPeucetia(Oxyopidae) with Plants Bearing Glandular Hairs
Authors: Vasconcellos‐Neto João , Romero Gustavo Q. , Santos Adalberto J. , Dippenaar‐Schoeman Ansie S.
Published: January 2007

Two common South American species of lynx spiders,Peucetia rubrolineataandP. flava(Oxyopidae), were surveyed on three localities in southeastern Brazil to determine plant choice. Both species were found to be associated with plants bearing glandular trichomes. A literature review and complementary data show that tenPeucetiaspecies are associated with up to 55 plant species bearing glandular trichomes in at least 20 distinct vegetation types (phytophysiognomies) in more than 36 localities in the Neotropical, Neartic, Afrotropical, and Paleartic regions. The main plant families used by the spiders were Solanaceae, Asteraceae, and Melastomataceae. The specialization of thePeucetiaspecies for plants bearing glandular trichomes may have evolved because insects adhered to these sticky structures may be used as prey by the spiders.
Evidence for Exploitative Competition: Comparative Foraging Behavior and Roosting Ecology of Short‐Tailed Fruit Bats (Phyllostomidae)
Authors: Bonaccorso Frank J. , Winkelmann John R. , Shin Danny , Agrawal Caroline I. , Aslami Nadia , Bonney Caitlin , Hsu Andrea , Jekielek Phoebe E. , Knox Allison K. , Kopach Stephen J. , Jennings Tara D. , Lasky Jesse R. , Menesale Sarah A. , Richards Jeannine H. , Rutland Jessica A. , Sessa Anna K. , Zhaurova Luba , Kunz Thomas H.
Published: January 2007

Chestnut short‐tailed bats, Carollia castanea, and Seba's short‐tailed bats, C. perspicillata (Phyllostomidae), were radio‐tracked (N= 1593 positions) in lowland rain forest at Tiputini Biodiversity Station, Orellana Province, Ecuador. For 11 C. castanea, mean home range was 6.8 ± 2.2 ha, mean core‐use area was 1.7 ± 0.8 ha, and mean long axis across home range was 438 ± 106 m. For three C. perspicillata, mean home range was 5.5 ± 1.7 ha, mean core‐use area was 1.3 ± 0.6 ha, and mean long axis was 493 ± 172 m. Groups of less than five C. castanea occupied day‐roosts in earthen cavities that undercut banks the Tiputini River. Carollia perspicillata used tree hollows and buildings as day‐roosts. Interspecific and intraspecific overlap among short‐tailed bats occurred in core‐use areas associated with clumps of fruiting Piper hispidum (peppers) and Cecropia sciadophylla. Piper hispidum seeds were present in 80 percent of the fecal samples from C. castanea and 56 percent of samples from C. perspicillata. Carollia perspicillata handled pepper fruits significantly faster than C. castanea; however, C. castanea commenced foraging before C. perspicillata emerged from day‐roosts. Evidence for exploitative competition between C. castanea and C. perspicillata is suggested by our observations that 95 percent of ripe P. hispidum fruits available at sunset disappear before sunrise (N= 74 marked fruits). Piper hispidum plants produced zero to 12 ripe infructescences per plant each night during peak production. Few ripe infructescences of P. hispidum were available during the dry season; however, ripe infructescences of C. sciadophylla, remained abundant.
Female Fecundity Is Dependent on Substrate, Rather Than Male Abundance, in the Wind‐Pollinated, Dioecious Understory Palm Chamaedorea radicalis
Authors: Berry Eric J. , Gorchov David L.
Published: January 2007

We examined the impact of substrate, population density, and sexual composition on female reproductive success in harvested populations of the tropical understory palm Chamaedorea radicalis. Leaf harvest for the international floral greenery trade does not kill palms, but has been shown to reduce flowering frequency and has been projected to reduce population growth. Because C. radicalis is dioecious and wind‐pollinated, a reduction in flowering density from leaf harvest or other anthropogenic factors may lower pollen movement between flowering conspecifics and lower fruit production. Such reduced fecundity in harvested populations can contribute to an Allee effect, where the per capita rate of population growth declines at low density. We tested for these effects by sampling C. radicalis along transects in ten populations, spanning a range of densities, during May (flowering peak) and August (fruiting peak) 2002. We applied path analysis using structural equation modeling (SEM) to test a set of hypothesized relationships between substrate, female size, several population parameters, and female fecundity. SEM models revealed that female fecundity was not dependent on any measure of population density or sexual composition, providing no evidence for an Allee effect. The strongest model (R2= 92.9%) related C. radicalis reproductive output only to substrate, female size, flower number, and proportional fruit set. This model revealed that palms on rock outcrops were larger, produced more flowers, and had higher proportional fruit set than palms on the forest floor. This finding suggests that protection of females on outcrops should enhance population growth and viability.
Vascular Epiphyte Communities in the Inner‐Crown of Hyeronima alchorneoides and Lecythis ampla at La Selva Biological Station, Costa Rica
Authors: Cardelús Catherine L.
Published: January 2007

The community composition and percent cover of vascular epiphytes were examined in relation to photosynthetic photon flux density (PFD), temperature, vapor pressure, and tree characteristics in the inner‐crown of two emergent tree species, Hyeronima alchorneoides and Lecythis ampla, at La Selva Biological Station, Costa Rica. A total of 53 species were found in a total sampled branch area of 32 m2 in eight trees—four trees per species. Community composition varied both among individuals of the same tree species and between tree species. However, percent cover patterns of vascular epiphytes were significantly different between the two tree species; Hyeronima had a significantly greater percent cover of epiphytes than Lecythis. The higher percent light transmittance as well as lower humidity in Lecythis are likely causes of its lower percent cover of epiphytes.
Stabilimenta of Philoponella vicina (Araneae: Uloboridae) and Gasteracantha cancriformis (Araneae: Araneidae): Evidence Against a Prey Attractant Function
Authors: Eberhard William G.
Published: January 2007

Both the uloborid Philoponella vicina and the araneid Gasteracantha cancriformis spiders sometimes placed silk stabilimenta on non‐orb “resting webs” that consisted of only one or a few lines. These webs completely lacked sticky silk, so their stabilimenta could not function to attract prey. Some non‐orbs were built by spiders when their orb webs are damaged. These observations contradict the prey attraction camouflage hypothesis for stabilimentum function, but are compatible with the spider camouflage and web advertisement to avoid web destruction hypotheses.
GROWTH OF EUROTIUM CHEVALIERI IN MILK JAM: INFLUENCE OF PH, POTASSIUM SORBATE AND WATER ACTIVITY
Authors: CHAR CIELO D. , GUERRERO SANDRA N. , ALZAMORA STELLA M.
Published: January 2007

Milk jam (dulce de leche) is a typical Argentine sweet spread prepared by milk evaporation to about 70% w/w total solids at atmospheric pressure with added sucrose, glucose and vanillin. Growth of xerophilic molds represents a severe problem in this type of intermediate moisture product. This study evaluated the growth response of Eurotium chevalieri in milk jam with different potassium sorbate (KS) concentrations (0, 500, 1,000, 1,500 and 2,000 ppm) at selected water activity (aw) values (≅0.80 and 0.85) and two pH levels (≅5.5 and 6.0) stored at room temperature (25C) for 90 days. Growth curves were characterized by the modified Gompertz model, and the effect of the independent variables on the estimated parameters (maximum specific growth rate, vm, and lag time, λ) was analyzed through polynomial equations. Growth of E. chevalieri was prevented for at least 90 days when the addition of 1,000 ppm KS was combined with a decrease in aw to 0.80 and ph 5.5. The boundary between growth and nongrowth of E. chevalieri as a function of aw, pH, KS and storage time was also predicted by means of the probabilistic model using logistic regression, which provided a wide range of formulation possibilities depending on the targeted shelf life.