bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effects of Market Network Heterogeneity on Innovation Diffusion: An Agent‐Based Modeling Approach
Authors: Bohlmann Jonathan D. , Calantone Roger J. , Zhao Meng
Published: July 2010

Innovations usually have an initial impact on very few people. The period of learning or early evaluation precedes the diffusion of the technology into the wider addressed population. More than a transfer, this is best characterized as communication of benefits, costs, and compatibility with earlier technologies and a relative assessment of the new state of the art. Innovation development by an organization or individual creates not just a device (i.e., process or tacit knowledge) but concomitantly a capacity on the part of other organizations or persons to use, adopt, replicate, enhance, or modify the technology, skills, or knowledge for their own purposes. How innovations actually diffuse is to understand the communication of progress, and this framing helps one to design innovations and also design the marketing and testing programs to ready innovations for market and launch them efficiently. Diffusion theory's main focus is on the flow of information within a social system, such as via mass media and word‐of‐mouth communications. This theory presents often in the form of mathematical models of innovation and imitation. Distinct from classical diffusion models, however, consumers are not all identical in how they connect to others within a market or how they respond to information. We examine the effects of various network structures and relational heterogeneity on innovation diffusion within market networks. Specifically, network topology (the structure of how individuals in the market are connected) and the strength of communication links between innovator and follower market segments (a form of relational heterogeneity) are studied. Several research questions concerning network heterogeneity are addressed with an agent‐based modeling approach. The present study's findings are based on simulation results that show important effects of network structure on the diffusion process. The ability to speed diffusion varies significantly according to within‐ and cross‐segment communications within a heterogeneous network structure. The implications of the present approach for new product diffusion are discussed, and future research directions are suggested that may add useful insights into the complex social networks inherent to diffusion. A simple summary is that discovery of significant prime communicator nodes in a network allows innovation development practices to be better calibrated to realistically multiple market segments.
Syndication in Venture Capital Financing
Authors: Deli Daniel N. , Santhanakrishnan Mukunthan
Published: July 2010

We examine syndication in venture capital (VC) investments between 1980 and 2005. We argue that VC firms syndicate investments to mitigate human capital and financial constraints within individual VC firms and to reduce uncertainty about firm value. Our results are consistent with those arguments. We find that syndication is more likely for firms in the earliest stage of development and firms in the last stage of development as private firms (when human capital investments are greatest), for firms requiring the largest amounts of financial capital, and for firms with greater growth opportunities (those that are most difficult to value).
Bond Market Access, Credit Quality, and Capital Structure: Canadian Evidence
Authors: Mittoo Usha R. , Zhang Zhou
Published: July 2010

We examine the impact of bond market access (measured by having a credit rating) on leverage for Canadian high credit quality (HQ) and low credit quality (LQ) firms, and find that the leverage impact is more pronounced for LQ firms. The results are similar for U.S. firms. Our results are confirmed when we control for the firm's credit quality, examine the change in leverage around rating initiation, and account for the issue size effect. A similar leverage impact for Canadian and U.S. LQ firms suggests that the Canada‐U.S. bond market integration has mitigated the financial constraints for Canadian LQ firms.
Debt Maturity, Credit Risk, and Information Asymmetry: The Case of Municipal Bonds
Authors: Daniels Kenneth , Diro Ejara Demissew , Vijayakumar Jayaraman
Published: July 2010

Using a system of equations approach, this paper empirically tests the impact of credit quality, asset maturity, and other issuer and issue characteristics on the maturity of municipal bonds. We find that under conditions of lower information asymmetry that prevails in the municipal sector, higher‐rated bonds have longer maturities than low‐rated bonds. This result differs from that observed in the corporate sector. Overall, our results support the asset maturity hypothesis. In addition, our analysis finds that fundamentals matter. Issue features that provide additional protection or convenience to the investor tend to increase debt maturity.
Earnings Management Surrounding New Debt Issues
Authors: Liu Yixin , Ning Yixi , Davidson III Wallace N.
Published: July 2010

We examine whether firms manage earnings before issuing bonds to achieve a lower cost of borrowing. We find significant income‐increasing earnings management prior to bond offerings. We also find that firms that manage earnings upward issue debt at a lower cost, after controlling for various bond issuer and issue characteristics. Our results are consistent with studies that report earnings management around equity issuance. The results indicate that, like equity holders, bondholders fail to see through the inflated earnings numbers in pricing new debt.
SEO Cycles
Authors: Howe John S. , Zhang Shaorong
Published: July 2010

Public equity offerings by seasoned firms (SEOs) exhibit similar but less volatile cycles than initial public offerings (IPOs) of newly public firms. Our paper provides a comprehensive examination of the factors that cause variation in the number of firms issuing SEOs. Specifically, we use four factors from studies of IPOs as potential determinants of SEO cycles. We find that whether tested separately or collectively, only the demand for capital and market timing hypotheses receive strong empirical support in explaining SEO volume. Investor sentiment is not an important factor in explaining SEO volume, nor is information asymmetry.
Corporate Hedging Policy and Equity Mispricing
Authors: Lin J. Barry , Pantzalis Christos , Park Jung Chul
Published: July 2010

We show that firms’ use of derivatives is negatively associated with stock mispricing. This result is consistent with the notion that hedging improves the transparency and predictability of firms’ cash flows resulting in less misvaluation. Furthermore, we show that the negative relationship between mispricing and hedging is particularly strong when market value is below fundamental value, which is consistent with prior evidence that hedging has a positive impact on firm valuation. Finally, we provide evidence that a “spread‐out” hedging policy that entails the use of a variety of derivative contracts can be more effective in reducing mispricing.
Restructuring Using Operating Asset Exchanges: Issues and Evidence
Authors: Campbell Kaysia , Owers James E.
Published: July 2010

This study examines restructuring in which a firm divests an operating asset in exchange for another operating asset. Since liquidity, capital structure, and distributional issues are not immediately associated with tax‐free asset‐for‐asset exchanges, they are well suited for examining the competing hypotheses related to divestitures. We find that the abnormal returns associated with asset exchanges are generally smaller than those associated with other divestiture restructurings except when indications of value are provided. Our analysis identifies positive valuation effects for firms undertaking focus‐enhancing exchanges, but a dominating consideration is whether the value of the units traded is indicated.
What are the Capital Structure Determinants for Tax‐Exempt Organizations?
Authors: Peter Smith Geoffrey
Published: July 2010

I study the determinants of capital structure in the absence of tax incentives. I find that debt use is positively related to asset tangibility, growth, and size, and negatively related to age, liquidity, and profitability. Tax‐exempt sector‐specific findings indicate that debt is also positively related to the efficacy of state laws against the misuse of assets and to the percentage of decision makers that are paid and negatively related to decision‐maker compensation and to charitable contributions. Religious organizations most commonly borrow from internal sources, those in education use tax‐exempt bonds, while human services organizations use mortgages and notes payable.
Political Risk and Purchases of Privatized State‐Owned Enterprises
Authors: Glambosky Mina C. , Gleason Kimberly C. , Madura Jeff
Published: July 2010

We assess the valuation effects and risk for acquirers of privatized state‐owned enterprises (SOEs). The valuation effects of purchasers are positive and significant; they increase for purchasers that have recent high performance, better access to capital, and have engaged in larger acquisitions. The acquirer valuation effects are lower when the selling government is more corrupt, more bureaucratic, and a weaker financial performer. Acquirer's total and unsystematic risk increases, indicating that purchasers of SOEs realize diversification benefits. Systematic risk increases for purchasers when the government is characterized by high political risk.
Atypical Electrocardiographic Features of Cavotricuspid Isthmus‐Dependent Atrial Flutter Occurring during Left Atrial Fibrillation Ablation
Authors: Chyou Janice Y. , Hickey Kathleen , Diamond Laurence , Whang William , Dizon Jose , Garan Hasan , Biviano Angelo
Published: July 2010

Background: Patients who have undergone percutaneous catheter ablation for atrial fibrillation (AF) may develop cavotricuspid isthmus (CTI)‐dependent atrial flutter (AFL), which can occur either spontaneously during left atrial (LA) ablation for AF or by induction from sinus rhythm during the procedure. The electrocardiographic (ECG) characteristics of CTI‐dependent AFL occurring during LA ablation have not been described. The purpose of this study was to describe the ECG features of CTI‐dependent AFL occurring during percutaneous LA catheter ablation for AF.

Methods and Results: Of 223 patients presenting for first AF ablation at our institution between May 2004 and February 2008, 20 patients (9%) developed CTI‐dependent AFL during LA ablation for AF. CTI‐dependent AFL developed spontaneously in 4 patients (20%) and was induced in 16 patients (80%). Among these 20 patients, 3 (15%) had typical ECG patterns and 17 (85%) had atypical ECG patterns. Flutter waves in the inferior leads were biphasic in 10 patients (50%), downward in 3 patients (15%), positive in 3 patients (15%), and not fitting the above classifications in 4 patients (20%). There was no statistically significant association between AFL pattern and LA size, left ventricular ejection fraction, total ablation time, duration of prior AF, or type of prior AF.

Conclusion: A majority of patients with CTI‐dependent AFL occurring during LA ablation have atypical ECG patterns. Biphasic flutter waves in the inferior leads are common ECG features, occurring in one‐half of patients. Right atrial CTI‐dependent AFL should be suspected even if the ECG appearance is atypical.

Ann Noninvasive Electrocardiol 2010;15(3):200–208
Is Rhythm‐Control Superior to Rate‐Control in Patients with Atrial Fibrillation and Diastolic Heart Failure?
Authors: Kong Melissa H. , Shaw Linda K. , O’Connor Christopher , Califf Robert M. , Blazing Michael A. , Al‐Khatib Sana M.
Published: July 2010

Background: Although no clinical trial data exist on the optimal management of atrial fibrillation (AF) in patients with diastolic heart failure, it has been hypothesized that rhythm‐control is more advantageous than rate‐control due to the dependence of these patients’ left ventricular filling on atrial contraction. We aimed to determine whether patients with AF and heart failure with preserved ejection fraction (EF) survive longer with rhythm versus rate‐control strategy.

Methods: The Duke Cardiovascular Disease Database was queried to identify patients with EF > 50%, heart failure symptoms and AF between January 1,1995 and June 30, 2005. We compared baseline characteristics and survival of patients managed with rate‐ versus rhythm‐control strategies. Using a 60‐day landmark view, Kaplan‐Meier curves were generated and results were adjusted for baseline differences using Cox proportional hazards modeling.

Results: Three hundred eighty‐two patients met the inclusion criteria (285 treated with rate‐control and 97 treated with rhythm‐control). The 1‐, 3‐, and 5‐year survival rates were 93.2%, 69.3%, and 56.8%, respectively in rate‐controlled patients and 94.8%, 78.0%, and 59.9%, respectively in rhythm‐controlled patients (P > 0.10). After adjustments for baseline differences, no significant difference in mortality was detected (hazard ratio for rhythm‐control vs rate‐control = 0.696, 95% CI 0.453–1.07, P = 0.098).

Conclusions: Based on our observational data, rhythm‐control seems to offer no survival advantage over rate‐control in patients with heart failure and preserved EF. Randomized clinical trials are needed to verify these findings and examine the effect of each strategy on stroke risk, heart failure decompensation, and quality of life.

Ann Noninvasive Electrocardiol 2010;15(3):209–217
A Bizarre Electrocardiographic Pattern Due to Chronic Lithium Therapy
Authors: Kayrak Mehmet , Duman Cetin , Gul Enes Elvin , Sonmez Osman , Kaya Zeynettin , Arı Hatem
Published: July 2010

Cardiotoxicity that results from lithium overdose is uncommon and electrocardiographic (ECG) changes are rarely reported. However, some authors have specifically reported the occurrence of ischemic ECG changes due to a lithium overdose. This article describes a case that is demonstrating ECG changes that mimic inferior myocardial infarction during the course of chronic lithium treatment and showing QTc prolongation in this patient. The patients’ ECG changes were partially recovered after hemodialysis.

Ann Noninvasive Electrocardiol 2010;15(3):289–292
Repeatability of Sleep Apnea Detection in 48‐Hour Holter ECG Monitoring
Authors: Uznańska Barbara , Trzos Ewa , Rechciński Tomasz , Kasprzak Jarosław D. , Kurpesa Małgorzata
Published: July 2010

Background: There is a significant relationship between obstructive sleep apnea (OSA) and cardiovascular diseases. Reliability of new methods evaluating apnea in Holter ECG monitoring is still the matter of investigators’ studies.

Methods: In 48‐hour Holter ECG monitoring recordings of 63 patients, we assessed repeatability, comparing the results from both sleep periods.

Results: We found good repeatability in evaluation of apnea‐hypopnea index value. There was moderate agreement in three categories, that is, normal or bordeline or apneic assignment. Assignment to “healthy” (normal and borderline) or apneic subgroup during consecutive sleep periods showed high repeatability.

Conclusions: Holter ECG monitoring is a repetitive method of preliminary diagnosis in patients evaluated for sleep apnea syndrome.

Ann Noninvasive Electrocardiol 2010;15(3):218–222
Heart Rate Turbulence for Prediction of Heart Transplantation and Mortality in Chronic Heart Failure
Authors: Sredniawa Beata , Cebula Sylwia , Kowalczyk Jacek , Batchvarov Velislav N. , Musialik‐Lydka Agata , Sliwinska Anna , Wozniak Aleksandra , Zakliczynski Michal , Zembala Marian , Kalarus Zbigniew
Published: July 2010

Background: Previous studies have shown conflicting results about the value of heart rate turbulence (HRT) for risk stratification of patients (pts) with chronic heart failure (CHF). We prospectively evaluated the relation between HRT and progression toward end‐stage heart failure or all‐cause mortality in patients with CHF.

Methods: HRT was assessed from 24‐hour Holter recordings in 110 pts with CHF (54 in NYHA class II, 56 in class III–IV; left ventricular ejection fraction (LVEF) 30%± 10%) on optimal pharmacotherapy and quantified as turbulence onset (TO,%), turbulence slope (TS, ms/RR interval), and turbulence timing (beginning of RR sequence for calculation of TS, TT). TO ≥ 0%, TS ≤ 2.5 ms/RR, and TT >10 were considered abnormal. End point was development of end‐stage CHF requiring heart transplantation (OHT) or all‐cause mortality.

Results: During a follow‐up of 5.8 ± 1.3 years, 24 pts died and 10 required OHT. TO, TS, TT, and both (TO and TS) were abnormal in 35%, 50%, 30%, and 25% of all patients, respectively. Patients with at least one relatively preserved HRT parameter (TO, TS, or TT) (n = 98) had 5‐year event‐free rate of 83% compared to 33% of those in whom all three parameters were abnormal (n = 12). In multivariate Cox regression analysis, the most powerful predictor of end point events was heart rate variability (SDNN < 70 ms, hazard ratio (HR) 9.41, P < 0.001), followed by LVEF ≤ 35% (HR 6.23), TT ≥ 10 (HR 3.14), and TO ≥ 0 (HR 2.54, P < 0.05).

Conclusion: In patients with CHF on optimal pharmacotherapy, HRT can help to predict those at risk for progression toward OHT or death of all causes.

Ann Noninvasive Electrocardiol 2010;15(3):230–237
Effects of Head‐Up Tilt‐Table Test on the QT Interval
Authors: Findler Michael , Birger Amir , Diamant Shmuel , Viskin Sami
Published: July 2010

Background. The QT interval shortens in response to sympathetic stimulation and its response to epinephrine infusion (in healthy individuals and patients with long QT syndrome) has been thoroughly studied. Head‐up tilt‐table (HUT) testing is an easy way to achieve brisk sympathetic stimulation. Yet, little is known about the response of the QT interval to HUT.

Methods. We reviewed the electrocardiograms of HUT tests performed at our institution and compare the heart rate, QT, and QTc obtained immediately after HUT with the rest values.

Results. The study group consisted of 41 patients (27 females and 14 males) aged 23.9 ± 8.4 years. Head‐up tilting led to a significant shortening of the RR interval (from 825 ± 128 msec at rest phase to 712 ± 130 msec in the upward tilt phase, P < 0.001) but only to a moderate shortening of the QT interval (from 363.7 ± 27.9 msec during rest to 355 ± 30.3 msec during upward tilt, P = 0.001). Since the RR interval shortened more than the QT interval, the QTc actually increased (from 403 ± 21.5 msec during rest phase to 423.2 ± 27.4 msec during upward tilt, P < 0.001). The QTc value measured for the upward tilt position was longer than the resting QTc value in 33 of 41 patients. Of those, 4 male patients and 2 female patients developed upward‐tilt QTc values above what would be considered abnormal at rest.

Conclusions. During HUT the QT shortens less than the RR interval. Consequently, the QTc increases during head‐up tilt.

Ann Noninvasive Electrocardiol 2010;15(3):245–249
Predictors of Long‐Term Risk for Heart Failure Hospitalization after Acute Myocardial Infarction
Authors: Perkiömäki Juha S. , Hämekoski Sari , Junttila M. Juhani , Jokinen Vesa , Tapanainen Jari , Huikuri Heikki V.
Published: July 2010

Background: Data on the value of baseline brain natriuretic peptide (BNP) and autonomic markers in predicting heart failure (HF) hospitalization after an acute myocardial infarction (AMI) are limited.

Methods: A consecutive series of patients with AMI without a previous history of HF (n = 569) were followed up for 8 years. At baseline, the patients had a blood sample for determination of BNP, a 24‐hour Holter recording for evaluating heart rate variability (HRV) and heart rate turbulence (HRT), and an assessment of baroreflex sensitivity (BRS) using phenylephrine test.

Results: During the follow‐up, 79 (14%) patients were hospitalized due to HF. Increased baseline BNP, decreased HRV, HRT, and BRS had a significant association with HF hospitalization in univariate comparisons (P < 0.001 for all). After adjusting with all the relevant clinical parameters, BNP, HRV, and HRT still significantly predicted HF hospitalization (P < 0.001 for BNP and for the short‐term scaling exponent α1, P < 0.01 for turbulence slope). In the receiver operator characteristics curve analysis, the area under the curve for BNP was 0.77, for the short‐term scaling exponent α1 0.69, for turbulence slope 0.71, and for BNP/standard deviation of all N‐N intervals ratio 0.80.

Conclusion: Baseline increased BNP and impaired autonomic function after AMI yield significant information on the long‐term risk for HF hospitalization.

Ann Noninvasive Electrocardiol 2010;15(3):250–258
Dynamics and Rate‐Dependence of the Spatial Angle between Ventricular Depolarization and Repolarization Wave Fronts during Exercise ECG
Authors: Kenttä Tuomas , Karsikas Mari , Kiviniemi Antti , Tulppo Mikko , Seppänen Tapio , Huikuri Heikki V.
Published: July 2010

Background: QRS/T angle and the cosine of the angle between QRS and T‐wave vectors (TCRT), measured from standard 12‐lead electrocardiogram (ECG), have been used in risk stratification of patients. This study assessed the possible rate dependence of these variables during exercise ECG in healthy subjects.

Methods: Forty healthy volunteers, 20 men and 20 women, aged 34.6 ± 3.4, underwent an exercise ECG testing. Twelve‐lead ECG was recorded from each test subject and the spatial QRS/T angle and TCRT were automatically analyzed in a beat‐to‐beat manner with custom‐made software. The individual TCRT/RR and QRST/RR patterns were fitted with seven different regression models, including a linear model and six nonlinear models.

Results: TCRT and QRS/T angle showed a significant rate dependence, with decreased values at higher heart rates (HR). In individual subjects, the second‐degree polynomic model was the best regression model for TCRT/RR and QRST/RR slopes. It provided the best fit for both exercise and recovery. The overall TCRT/RR and QRST/RR slopes were similar between men and women during exercise and recovery. However, women had predominantly higher TCRT and QRS/T values. With respect to time, the dynamics of TCRT differed significantly between men and women; with a steeper exercise slope in women (women, −0.04/min vs −0.02/min in men, P < 0.0001). In addition, evident hysteresis was observed in the TCRT/RR slopes; with higher TCRT values during exercise.

Conclusions: The individual patterns of TCRT and QRS/T angle are affected by HR and gender. Delayed rate adaptation creates hysteresis in the TCRT/RR slopes.

Ann Noninvasive Electrocardiol 2010;15(3):264–275
Determination of formaldehyde in formaldehyde‐releaser patch test preparations
Authors: Emeis Detlef , De Groot Anton C. , Brinkmann Jürgen
Published: July 2010

Background: Positive patch test reactions to formaldehyde‐releasers in patients co‐reacting to formaldehyde are often ascribed to formaldehyde allergy. However, the formaldehyde content of patch test materials has not been investigated.

Objectives: To demonstrate and quantify free formaldehyde in commercial patch test materials and in prepared aqueous solutions of formaldehyde releasers.

Materials: Free formaldehyde was measured by 13C NMR Spectroscopy in (i) all formaldehyde‐releasers in water available from Chemotechnique® and Brial®, (ii) 5 releasers in petrolatum, (iii) 12 prepared aqueous solutions of formaldehyde‐releasers and (iv) water that had been in contact with petrolatum test samples.

Results: In none of the five petrolatum test substances was free formaldehyde found. In all nine commercial aqueous patch test substances and 9 of the 12 prepared solutions, free formaldehyde was demonstrated with concentrations ranging from 0.019% to 0.37% (detection limit 0.01%). Contact of the petrolatum test samples with water resulted in the release of formaldehyde.

Conclusions: Most aqueous solutions of formaldehyde‐releasers contain free formaldehyde. Petrolatum‐based patch test materials with formaldehyde‐releasers do not contain free formaldehyde, but probably start releasing it upon contact with water. Therefore, in future studies, determination of free and releasable formaldehyde may be preferable.
Patch test reactivity to metal allergens following regulatory interventions: a 33‐year retrospective study
Authors: Thyssen Jacob Pontoppidan , Ross‐Hansen Katrine , Menné Torkil , Johansen Jeanne Duus
Published: July 2010

Background: Contact allergy epidemics to chromate and nickel were addressed in Denmark in 1983 and 1990 by regulatory interventions.

Objectives: To evaluate whether regulatory interventions on nickel and chromate exposure have reduced the proportion of strong patch test reactions.

Methods: 22 506 patients with dermatitis aged 4–99 years were patch tested with nickel sulfate, potassium dichromate, or cobalt chloride between 1977 and 2009.

Results: The proportion of 3+ reactions to nickel sulfate was reduced and almost disappeared after the mid‐ and late 1980s (P‐trend = 0.001). Today, 1+ and 2+ nickel reactions occur equally frequent. Cobalt chloride patch test reactivity reflected the nickel development to some degree. The proportion of 3+ reactions to potassium dichromate was reduced during the 1980s (P‐trend = 0.13), whereas the proportion of 2+ reactions to potassium dichromate have increased in recent years.

Conclusions: The decrease in nickel sulfate and cobalt chloride 3+ patch test reactivity began long before the Danish nickel regulation came into effect. This could be because of research activity at the time as well as political attention in Northern Europe. The chromate content in cement regulation may have changed the epidemiology of patch test reactivity; however, in recent years, 2+ reactions to chromate have increased markedly, a development that should be carefully followed.
WT1 peptide vaccine induces reduction in minimal residual disease in an Imatinib‐treated CML patient
Authors: Oji Yusuke , Oka Yoshihiro , Nishida Sumiyuki , Tsuboi Akihiro , Kawakami Manabu , Shirakata Toshiaki , Takahashi Kazuko , Murao Ayako , Nakajima Hiroko , Narita Miwako , Takahashi Masuhiro , Morita Satoshi , Sakamoto Junichi , Tanaka Toshio , Kawase Ichiro , Hosen Naoki , Sugiyama Haruo
Published: July 2010

How to treat CML patients who are resistant to inhibitors of BCR‐ABL tyrosine kinase such as Imatinib is a very important and urgent issue in clinical hematology. Here, we report a case of Imatinib‐treated CML in which intradermally administered WT1 peptide vaccine elicited WT1‐specific immune responses and the resultant reduction in the persistent residual disease in co‐administration of Imatinib. BCR‐ABL mRNA levels were being maintained under the detection limit for 8 months since week 77 of vaccination. No adverse effects except local erythema at the injection sites were observed. The tetramer assay revealed that the decrease in BCR‐ABL mRNA levels was associated with the increase in frequency of WT1‐specific cytotoxic T lymphocytes, notably effector‐memory type of that, in the patient’s peripheral blood. The case presented here indicates that WT1 peptide vaccine may become a safe and cure‐oriented therapy for CML patients who have residual disease regardless of the treatment with Imatinib.
Oral potentially malignant lesions: first‐level micro‐histological diagnosis from tissue fragments sampled in liquid‐based diagnostic cytology
Authors: Navone Roberto , Pentenero Monica , Rostan Isabella , Burlo Paola , Marsico Andrea , Broccoletti Roberto , Scully Crispian , Gandolfo Sergio
Published: July 2010

Background:  Scalpel biopsy may under‐diagnose oral dysplasia/carcinoma in potentially malignant lesions (PMLs) because samples represent only one or a few sites. It is possible that small tissue specimens obtained from over the whole area of PMLs, by scraping with a dermatological curette, could be treated histologically and used as ‘micro’ biopsies. This study values the accuracy of micro‐biopsies in the detection of dysplasia/carcinoma in oral PMLs.

Methods:  A prospective study was carried out on 164 patients with PMLs, with both scalpel and micro‐biopsies, for the presence of dysplasia/carcinoma. The most severe diagnosis (obtained by either method) was used as the reference standard. The presence/absence of the basement membrane zone (BMZ) in the micro‐biopsy specimens correlated with the site, the clinical features of the PMLs and the operator.

Results:  Micro‐biopsy gave six of 164 (3.66%) inadequate specimens. Of 158 of 164 adequate samples, dysplasia/carcinoma was diagnosed in 85 of 158 cases; micro‐biopsy diagnosis was in agreement with scalpel biopsy in 144 of 158 (91.14%) cases and showed a better sensitivity than did scalpel biopsy (97.65% vs. 85.88%), corresponding to two of 158 false‐negative cases by micro‐biopsy vs. 12 of 158 by scalpel biopsy. The BMZ was observed in 110 of 158 (69.62%) of all micro‐biopsies and had no relationship with the sampling site, the clinical features of the PMLs or the operator.

Conclusions:  The negative predictive value (97.33%) suggests that micro‐biopsy may well be an effective first‐level diagnostic procedure for PMLs (especially in follow‐ups and multiple lesions); moreover, in carcinoma (17% of cases) a definitive diagnosis could be made without further investigation.
Mechanism of action of tin‐containing fluoride solutions as anti‐erosive agents in dentine – an in vitro tin‐uptake, tissue loss, and scanning electron microscopy study
Authors: Ganss Carolina , Hardt Martin , Lussi Adrian , Cocks Ann‐Kristin , Klimek Joachim , Schlueter Nadine
Published: July 2010

Ganss C, Hardt M, Lussi A, Cocks A‐K, Klimek J, Schlueter N. Mechanism of action of tin‐containing fluoride solutions as anti‐erosive agents in dentine – an in vitro tin‐uptake, tissue loss, and scanning electron microscopy study. Eur J Oral Sci 2010; 118: 376–384. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci

Solutions containing tin and fluoride exhibit remarkable anti‐erosive properties with tin ions as a major agent. To elucidate its mechanism of action in dentine, the tin uptake on and in the tissue was investigated and related to histological findings and substance loss. Samples were treated twice daily, each treatment lasting for 2 min, with fluoride solutions [pH 4.5; 1,500 parts per million (p.p.m.) F] containing 2,100, 1,400, or 400 p.p.m. Sn as SnCl2. In experiments 1 and 2, samples were eroded with citric acid (pH 2.3) six times each day, each treatment lasting for 5 min; in experiment 2, the demineralized organic matrix was continuously digested by collagenase; in experiment 3, no erosive challenges were performed. Sample surfaces and cross‐sections were investigated using energy dispersive X‐ray spectroscopy, scanning electron microscopy, and profilometry. Surface retention of tin was found in almost all treatment groups and was highest in experiment 2. On cross‐sections, tin was retained within the organic matrix; in mineralized areas, tin was found mainly within a depth of 10 μm. Test solutions inhibited substance loss significantly; in experiment 2, the effect was dose‐dependent. Erosion inhibition seemed to depend mainly on the incorporation of tin in the mineralized dentine when the organic portion was preserved, but on surface precipitation when the organic portion was continuously digested.
Influence of light‐curing protocols on polymerization shrinkage and shrinkage force of a dual‐cured core build‐up resin composite
Authors: Tauböck Tobias T. , Bortolotto Tissiana , Buchalla Wolfgang , Attin Thomas , Krejci Ivo
Published: July 2010

Tauböck TT, Bortolotto T, Buchalla W, Attin T, Krejci I. Influence of light‐curing protocols on polymerization shrinkage and shrinkage force of a dual‐cured core build‐up resin composite. Eur J Oral Sci 2010; 118: 423–429. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci

This study investigated the influence of time delay and duration of photo‐activation on linear polymerization shrinkage, shrinkage force, and hardening of a dual‐cured core build‐up resin composite. The test material (Rebilda DC) was light‐cured for 20 or 60 s either early (2 min) or late (7 min) after the start of mixing. Non‐irradiated self‐cured specimens served as controls. Linear shrinkage and shrinkage force were measured for 60 min using custom‐made devices. Knoop hardness was determined at the end of the observation period. Self‐cured controls, showing a linear shrinkage similar to that of specimens early light‐cured for 20 s generated the lowest shrinkage force and hardness. A shorter light exposure time (20 s vs. 60 s) reduced linear shrinkage, shrinkage force, and hardness when early light‐curing was performed, but did not affect the three properties in specimens light‐cured late after the start of mixing. Late photo‐activation increased linear shrinkage, irrespective of irradiation time, and resulted in a higher shrinkage force and hardness for short light exposure time. A moderate correlation was found between the two shrinkage properties studied (r2 = 0.65). In conclusion, improvements in shrinkage behavior of the tested core build‐up material were associated with inferior hardening, making it important to adapt curing protocols to the clinical situation.
Nuclear and cytoplasmic expression of Met in oral squamous cell carcinoma and in an organotypic oral cancer model
Authors: Brusevold Ingvild J. , Søland Tine M. , Khuu Cuong , Christoffersen Thoralf , Bryne Magne
Published: July 2010

Brusevold IJ, Søland TM, Khuu C, Christoffersen T, Bryne M. Nuclear and cytoplasmic expression of Met in oral squamous cell carcinoma and in an organotypic oral cancer model. Eur J Oral Sci 2010; 118: 342–349. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci

Met, the hepatocyte growth factor receptor, is important in transducing signals for tumour growth and metastasis. The aim of this study was to examine the pattern of Met expression and its value as a prognostic factor in oral squamous cell carcinomas (OSCCs). The material consisted of 53 OSCCs and five healthy controls from normal oral mucosa supplied with cell lines, 10 organotypic models supplied with oral cancer cells, and three organotypic models supplied with normal keratinocytes. Met protein expression was assessed by immunohistochemistry and western blotting. Met expression was scarce and limited to the basal layer in normal oral mucosa, but was more extensive in the tumours. Cytoplasmic expression of Met was found in the majority of the tumours, and nuclear expression was found in 72%, including a high fraction of the cells located at the invasive front. Organotypic models with normal or malignant oral cells yielded principally similar results as in the mucosa and the cancers, respectively. A smaller amount of Met immunoreactivity was detected, by western blotting, in the nuclear fraction of cultured oral cancer cells. In conclusion, Met was upregulated in OSCCs and was also found in the nucleus. However, Met was not a marker for prognosis in this study.
The effect of initial treatment of periodontitis on systemic markers of inflammation and cardiovascular risk: a randomized controlled trial
Authors: Taylor Barbara , Tofler Geoffrey , Morel‐Kopp Marie‐Christine , Carey Helen , Carter Torren , Elliott Margaret , Dailey Colette , Villata Luke , Ward Christopher , Woodward Mark , Schenck Karl
Published: July 2010

Taylor B, Tofler G, Morel‐Kopp M‐C, Carey H, Carter T, Elliott M, Dailey C, Villata L, Ward C, Woodward M, Schenck K. The effect of initial treatment of periodontitis on systemic markers of inflammation and cardiovascular risk: a randomized controlled trial. Eur J Oral Sci 2010; 118: 350–356. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci

Observational studies indicate that chronic periodontal disease is associated with adverse cardiovascular outcomes. The aim of this study was to determine whether initial periodontal treatment has a beneficial effect on systemic markers of inflammation and cardiovascular risk. One hundred and thirty‐six adults with chronic periodontitis were allocated to either intervention or control groups in a 3‐month randomized controlled intervention study. The intervention group received initial periodontal treatment, whereas the control group did not receive that treatment until after the study. Blood levels of cardiovascular risk factors, and of hematological, inflammatory, and metabolic markers, were measured at the beginning and the end of the study, and differences were calculated. Fibrinogen level was the primary outcome measure. Data for 61 persons in the intervention group and for 64 persons in the control group were available for statistical analysis. Compared with the control group, the intervention group showed a non‐significant trend for a lower fibrinogen level. Significant increases in hemoglobin and hematocrit were seen after treatment, showing that initial periodontal treatment, a relatively simple and cost‐effective intervention, has systemic effects.
Microbiota around teeth and dental implants in periodontally healthy, partially edentulous patients: is pre‐implant microbiological testing relevant?
Authors: Meijndert Leo , Van Der Reijden Wil A. , Raghoebar Gerry M. , Meijer Henny J. A. , Vissink Arjan
Published: July 2010

Meijndert L, van der Reijden WA, Raghoebar GM, Meijer HJA, Vissink A. Microbiota around teeth and dental implants in periodontally healthy, partially edentulous patients: is pre‐implant microbiological testing relevant? Eur J Oral Sci 2010; 118: 357–363. © 2010 The Authors. Journal compilation © 2010 Eur J Oral Sci

This study aimed to assess the prevalence of seven periodontal marker pathogens, before implant placement and 1 yr after loading, in periodontally healthy individuals and to assess the long‐term effectiveness of pre‐implant reduction of pathogens to below threshold levels. In 93 individuals needing single tooth replacement, pooled subgingival microbiological samples from standard sites were cultured and analyzed before implant treatment and 1 yr after loading. Threshold levels commonly used in periodontology to predict periodontal breakdown were applied. Subjects with levels of pathogens above these thresholds received initial periodontal treatment including systemic antibiotics when indicated. At baseline, 49.5% of periodontally healthy subjects harboured one or more marker pathogens above threshold levels. Periodontal treatment reduced the pathogen levels below threshold values in 78.3% of these initially colonized subjects. In all cases Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis were reduced to below threshold. At 1 yr after loading, periodontal pathogens were present above threshold levels in 74.1% of all subjects. It is concluded that in almost half of periodontal healthy individuals the subgingival biofilm harbours periodontal pathogens above threshold values. Long‐term effectiveness of pre‐implant reduction of the selected marker pathogens appeared limited in our patient population, making pre‐implant reduction unpredictive for post‐implant levels of these pathogens. Thus, considering the applied microbiological criteria, generalized pre‐implant microbiological testing is not contributory in periodontally healthy subjects.
Stroke power consistency and 2000 m rowing performance in varsity rowers
Authors: Shimoda M. , Fukunaga T. , Higuchi M. , Kawakami Y.
Published: July 2010

We studied the relationship between stroke power consistency and 2000 m rowing time besides determining maximal oxygen uptake (VO2max) and leg extension power. The subjects (n=16, male varsity rowers) carried out an incremental test to volitional exhaustion on a rowing ergometer, and the VO2 at each stage was determined. The stroke power consistency was assessed by the coefficient of variation of power (CVPhigh) at the highest workload at which each subject could maintain power. Besides the incremental test, 2000 m all‐out rowing was performed on the ergometer and leg extension power was measured. Stepwise multiple regression analysis indicated that the 2000 m rowing time could be predicted by VO2max, leg extension power and CVPhigh in order of strength of standardized partial correlation coefficients as explanatory variables. The CVPhigh correlated with the residual of the regression between 2000 m rowing time and VO2max. The findings suggest that the stroke power consistency contributes to maintenance of the power during ergometer rowing.
A haplotype of glycogen synthase kinase 3β is associated with early onset of unipolar major depression
Authors: Saus E. , Soria V. , Escaramís G. , Crespo J. M. , Valero J. , Gutiérrez‐Zotes A. , Martorell L. , Vilella E. , Menchón J. M. , Estivill X. , Gratacòs M. , Urretavizcaya M.
Published: July 2010

Recent findings suggest that glycogen synthase kinase 3β (GSK3β) may play a role in the pathophysiology and treatment of mood disorders. Various genetic studies have shown the association of GSK3β polymorphisms with different mood disorder phenotypes. We hypothesized that genetic variants in the GSK3β gene could partially underlie the susceptibility to mood disorders. We performed a genetic case–control study of 440 psychiatrically screened control subjects and 445 mood disorder patients [256 unipolar major depressive disorder (MDD) and 189 bipolar disorder (BD)]. We genotyped a set of 11 single nucleotide polymorphisms (SNPs) and determined the relative frequency of a known copy number variant (CNV) overlapping the GSK3β by quantitative real‐time polymerase chain reaction (PCR). We found no evidence of association with MDD or BD diagnosis, and we further investigated the age at onset (AAO) of the disorder and severity of depressive index episode. We found that rs334555, located in intron 1 of GSK3β, was nominally associated with an earlier AAO of the disease in MDD (P = 0.001). We also identified a haplotype containing three SNPs (rs334555, rs119258668 and rs11927974) associated with AAO of the disorder (permutated P = 0.0025). We detected variability for the CNV, but we could not detect differences between patients and controls for any of the explored phenotypes. This study presents further evidence of the contribution of GSK3β to mood disorders, implicating a specific SNP and a haplotype with an earlier onset of the disorder in a group of well‐characterized patients with unipolar MDD. Further replication studies in patients with the same phenotypic characteristics should confirm the results reported here.
ΔFosB in the nucleus accumbens is critical for reinforcing effects of sexual reward
Authors: Pitchers K. K. , Frohmader K. S. , Vialou V. , Mouzon E. , Nestler E. J. , Lehman M. N. , Coolen L. M.
Published: July 2010

Sexual behavior in male rats is rewarding and reinforcing. However, little is known about the specific cellular and molecular mechanisms mediating sexual reward or the reinforcing effects of reward on subsequent expression of sexual behavior. This study tests the hypothesis that ΔFosB, the stably expressed truncated form of FosB, plays a critical role in the reinforcement of sexual behavior and experience‐induced facilitation of sexual motivation and performance. Sexual experience was shown to cause ΔFosB accumulation in several limbic brain regions including the nucleus accumbens (NAc), medial prefrontal cortex, ventral tegmental area and caudate putamen but not the medial preoptic nucleus. Next, the induction of c‐Fos, a downstream (repressed) target of ΔFosB, was measured in sexually experienced and naïve animals. The number of mating‐induced c‐Fos‐immunoreactive cells was significantly decreased in sexually experienced animals compared with sexually naïve controls. Finally, ΔFosB levels and its activity in the NAc were manipulated using viral‐mediated gene transfer to study its potential role in mediating sexual experience and experience‐induced facilitation of sexual performance. Animals with ΔFosB overexpression displayed enhanced facilitation of sexual performance with sexual experience relative to controls. In contrast, the expression of ΔJunD, a dominant negative binding partner of ΔFosB, attenuated sexual experience‐induced facilitation of sexual performance and stunted long‐term maintenance of facilitation compared to green fluorescence protein and ΔFosB overexpressing groups. Together, these findings support a critical role for ΔFosB expression in the NAc for the reinforcing effects of sexual behavior and sexual experience‐induced facilitation of sexual performance.
Modelling the impact of modifying lifestyle risk factors on dementia prevalence in Australian population aged 45 years and over, 2006–2051
Authors: Nepal Binod , Brown Laurie , Ranmuthugala Geetha
Published: July 2010

Aim:  To model impact of modifiable risk behaviour on dementia prevalence among the Australian population aged 45 years and over.

Methods:  A group‐based computer model was constructed to estimate the impact of modifying risk behaviour on dementia prevalence.

Results:  Based on population ageing, the number of people aged 45 years and over living with dementia is expected to triple from 187 000 in 2006 to 650 000 by 2051. A drop in proportion ever smokers by 5% every 5 years would lower population with dementia by 2% in 2051. If obesity rate drops by 5%, dementia prevalence would be lower by 6%. A decline in physical inactivity rate by 5% would reduce dementia by 11%. Persistence of the growing trend in obesity and physical inactivity would result in a larger than expected dementia epidemic.

Conclusion:  Improving the risk behaviours has potential to make a substantial reduction in the number of people with dementia.
Minimising harm to older Victorians from heatwaves: A qualitative study of the role of community‐based health profession and carer organisations
Authors: McInnes Judith A , Ibrahim Joseph E
Published: July 2010

Aim:  To investigate the role of community‐based health profession and carer organisations in Victoria in minimising harm to older people from heatwaves.

Methods:  A qualitative study based on semistructured interviews was conducted in Victoria, Australia. Twelve people were interviewed, representing four professional groups that support the health of older Victorians who reside at home.

Results:  None of the health profession and carer organisations studied had formalised heatwave strategies; however, their staff conduct a range of activities before and during heatwaves that may reduce harm to older clients. Interviewees discussed roles their organisations could play in a heatwave response plan, including coordination, identification of high‐risk individuals and education. All saw a need for extra resources and training if responses to heatwaves were required more frequently.

Conclusion:  It may be feasible to utilise the existing services and infrastructure of community‐based health profession and carer organisations operating in Victoria within a State‐wide Heatwave Response plan; however, this will require extra resources, training and coordination.