bluuebunny/crossref_metadata_2025 huggingface dataset:
Geographies of the financial crisis
Authors: Aalbers Manuel
Published: January 2009

Real estate is, by definition, local as it is spatially fixed. Mortgage lending, however, has developed from a local to a national market and is increasingly a global market today. An understanding of the financial crisis is ultimately a spatialised understanding of the linkages between local and global. This article looks at the geographies of the mortgage crisis and credit crunch and asks the question: how are different places affected by the crisis? The article looks at different states, different cities, different neighbourhoods and different financial centres. Investors in many places had invested in residential mortgage backed securities and have seen their value drop. Housing bubbles, faltering economies and regulation together have shaped the geography of the financial crisis on the state and city level in the US. Subprime and predatory lending have affected low‐income and minority communities more than others and we therefore not only see a concentration of foreclosures in certain cities, but also in certain neighbourhoods. On an international level, the long‐term economical and political consequences of this are still mostly unknown, but it is clear that some financial centres in Asia (including the Middle East) will become more important now that globalisation is coming full circle. This article does not present new empirical research, but brings together work from different literatures that all in some way have a specific angle on the financial crisis. The aim of this article is to make the geographical dimensions of the financial crisis understandable to geographers that are not specialists in all – or even any – of these literatures, so that they can comprehend the spatialisation of this crisis.
Intrinsic Toxicity of Hemoglobin: How to Counteract It
Authors: Simoni Jan , Simoni Grace , Moeller John F.
Published: January 2009

The development of safe and effective blood substitutes is of great importance in both civilian and military medicine. The currently tested hemoglobin (Hb)‐based oxygen carriers, however, have toxicity and efficacy problems. A number of unwanted effects have been observed in human trials, creating doubts about their clinical usefulness. In some subjects, vasoconstriction and decreased blood flow to the vital organs, heart attack, stroke, systemic inflammation, organ damage, and even death, have been attributed to the transfusion of these experimental products. Hb is a well‐known pressor agent and strong oxidant, although the full understanding of its intrinsic toxicity is yet to be uncovered. In particular, the complete mechanism of Hb‐induced vasoconstriction needs full elucidation. Knowledge of the biological events that trigger the induction of genes upon treatment with redox‐active Hb, as well as its catabolism, is still incomplete. It seems that our limited knowledge of free Hb effects in vivo is the main reason for not yet having a viable substitute of human blood. The future for universal red cell substitutes is in the new‐generation products that address all of Hb's intrinsic toxicity issues.
Radical Producing and Consuming Reactions of Hemoglobin: How Can We Limit Toxicity?
Authors: Cooper Chris E.
Published: January 2009

Hemoglobin has a range of enzymatic activities that can affect its putative pharmacological role as an extracellular oxygen carrier. In the presence of peroxides, deoxyhemoglobin and methemoglobin can produce free radicals and induce lipid peroxidation. Oxyhemoglobin can oxidize the free radical nitric oxide to nitrate, yet deoxyhemoglobin can produce nitric oxide from nitrite. These enzymatic reactions can induce or diminish toxic side reactions when hemoglobin is added in vivo. For example the removal of the free radical vasodilator nitric oxide, or the addition of the lipid‐derived vasoconstrictor F2‐isoprostane, will both alter blood flow and blood pressure. In order to determine the dominant effects it is necessary to design molecules with differing radical reactivities. Molecules have been designed with these modifications and this article will review their role in determining mechanism as well as their possible functionality as blood substitutes.
Liposome‐Encapsulated Hemoglobin Alleviates Brain Edema After Permanent Occlusion of the Middle Cerebral Artery in Rats
Authors: Kawaguchi Akira T. , Kurita Daisaku , Furuya Hiroyuki , Yamano Mariko , Ogata Yoshitaka , Haida Munetaka
Published: January 2009

Liposome‐encapsulated hemoglobin (LEH) was proven to be protective in cerebral ischemia/reperfusion injury. The present study evaluated LEH in a rat model of permanent middle cerebral artery (MCA) occlusion to clarify its effect during ischemia and reperfusion. Five minutes after thread occlusion of the MCA, rats were infused with 10 mL/kg of LEH (LEH, n = 13), and compared with normal controls (n = 11). Additional animals received the same MCA occlusion with no treatment (CT, n = 11), saline (saline, n = 10), empty liposome solution (EL, n = 13), or washed red blood cells (RBC, n = 7). Severity of brain edema was determined 24 h later by signal strength in T2‐weighted magnetic resonance imaging of the cortex, striatum, hippocampus, and pyriform lobe. The results showed that brain edema/infarction observed in any vehicle‐infused control was significantly more severe than in LEH‐treated rats. There was a tendency toward aggravated edema in rats receiving ELs. LEH infusion at a dose of 10 mL/kg significantly reduced edema formation as compared to other treatments in a wide area of the brain 24 h after permanent occlusion of the MCA. Low oncotic pressure of EL and LEH solution (vehicle solution) appeared to cause nonsignificant aggravation of edema and reduced protective effects of LEH.
Novel Controlling Mechanism of the Oxygen Affinity in Myoglobin With Isomeric Porphyrins
Authors: Neya Saburo , Suzuki Masaaki , Hoshino Tyuji
Published: January 2009

The biological function of the core modified porphyrin isomers such as porphycene, corrphycene, and hemiporphycene was examined. The iron complexes stoichiometrically coupled with apomyoglobin to afford stable holoproteins. The oxygen affinity of the reconstituted myoglobins (Mbs) changed over a 60 000‐fold range depending on the molecular structure of the prosthetic groups. For instance, a corrphycene with electronegative substituents to the bipyrrole part reduced the oxygen affinity of Mb to P50 = 300 mm Hg while the porphycene‐substituted Mb exhibited a P50 = 0.005 mm Hg. A notable increase in the oxygen delivery capacity of the corrphycene‐substituted Mb was explained on the basis of the trapezoidal corrphycene shape that stabilizes the iron displacement from the macrocycle plane toward the proximal histidine. The above observations demonstrate that the core modified heme isomers serve as novel molecular tools to regulate the oxygen affinity of Mb.
The Nursing Home Minimum Data Set for Vision and Its Association with Visual Acuity and Contrast Sensitivity
Authors: Swanson Mark W. , McGwin, Jr. Gerald , Elliott Amanda F. , Owsley Cynthia
Published: January 2009

OBJECTIVES: To evaluate the association between the Minimum Data Set's (MDS) Vision Patterns section and near and distance visual acuity and contrast sensitivity in nursing home residents.

DESIGN: Cross‐sectional study.

SETTING: Seventeen nursing homes in the Birmingham, Alabama, area.

PARTICIPANTS: Three hundred seventy‐one nursing home residents aged 55 and older with Mini‐Mental State Examination scores of 13 or greater.

MEASUREMENTS: The MDS 2.0 assessment for vision from the date closest to acuity and contrast sensitivity assessment were obtained from the resident's medical record. Acuity and contrast sensitivity were measured using the ETDRS chart and Pelli‐Robson chart, respectively.

RESULTS: The MDS rating of visual status was associated with distance and near visual acuity and contrast sensitivity. The MDS performed poorly in distinguishing residents with mild visual impairment from those with moderate visual impairment. For residents who were rated on the MDS as having adequate vision, 45.9% had distance acuity worse than 20/40 in the better eye, 72.8% had near acuity worse than 20/40 in the better eye, and 85.8% had contrast sensitivity less than 1.50.

CONCLUSION: The MDS 2.0 assessment for vision in nursing home residents is positively associated with visual acuity and contrast sensitivity but does not adequately distinguish between individuals with mild and moderate visual impairment and classifies many as having adequate vision who have visual impairment. The validity of the MDS 2.0 as a mechanism for triggering comprehensive eye care for nursing home residents is questionable.
Long‐Term Effect on Mortality of a Home Intervention that Reduces Functional Difficulties in Older Adults: Results from a Randomized Trial
Authors: Gitlin Laura N. , Hauck Walter W. , Dennis Marie P. , Winter Laraine , Hodgson Nancy , Schinfeld Sandy
Published: January 2009

OBJECTIVES: To evaluate the long‐term mortality effect of a home‐based intervention previously shown to reduce functional difficulties and whether survivorship benefits differ according to initial mortality risk level.

DESIGN: Two‐group randomized trial with survivorship followed up to 4 years from study entry.

SETTING: Homes of urban community‐living elderly people.

PARTICIPANTS: Three hundred nineteen adults aged 70 and older with difficulties performing daily activities.

INTERVENTION: Occupational and physical therapy sessions to instruct participants in compensatory strategies, home modifications, home safety, fall recovery techniques, and balance and muscle strength exercises.

MEASUREMENTS: Survival time was number of days between baseline interview and date of death, as determined using data from the National Death Index or December 31, 2005. Participants were stratified according to baseline mortality risk (low, moderate, high) using a prognostic indicator.

RESULTS: At 2 years, intervention participants (n=160) had a 5.6% mortality rate (n=9 deaths) and controls (n=159) a 13.2% rate (n=21 deaths; P=.02). Mortality rates remained lower for intervention participants up to 3.5 years from study entry. At 2 years, intervention participants with moderate mortality risk had a 16.7% mortality rate (n=16 deaths/96), compared with 28.2% for equivalent control group participants (n=24 deaths/85; P=.02). By 3 years, mortality rates were not statistically significantly different between the experimental and control groups.

CONCLUSIONS: The intervention extended survivorship up to 3.5 years and maintained statistically significant differences for 2 years. Subjects at moderate mortality risk derived the most intervention benefit. Findings suggest that the intervention could be a low‐cost clinical tool to delay functional decline and mortality.
Respiratory Syncytial Virus Outbreak in a Long‐Term Care Facility Detected Using Reverse Transcriptase Polymerase Chain Reaction: An Argument for Real‐Time Detection Methods
Authors: Caram L. Brett , Chen Jodi , Taggart E. William , Hillyard David R. , She Rosemary , Polage Christopher R. , Twersky Jack , Schmader Kenneth , Petti Cathy A. , Woods Christopher W.
Published: January 2009

OBJECTIVES: To report an outbreak of respiratory synctyial virus (RSV) in a long‐term care facility (LTCF) during ongoing routine respiratory illness surveillance.

DESIGN: Rapid antigen testing, viral culture, direct fluorescent antibody (DFA) testing, and reverse transcriptase polymerase chain reaction (RT‐PCR) testing for up to 15 viruses in symptomatic residents and chart review.

SETTING: A 120‐bed LTCF.

MEASUREMENTS: Comparison of rapid antigen testing, respiratory viral cultures, and DFA testing and RT‐PCR in residents with symptoms of a respiratory tract infection.

RESULTS: Twenty‐two of 52 residents developed symptoms of a respiratory tract infection between January 29, 2008, and February 26, 2008. RSV was detected using RT‐PCR in seven (32%) of the 22 cases. None of the seven cases had positive RSV rapid antigen testing, and only two had positive culture or DFA results. This outbreak occurred during a time when state wide RSV rates were rapidly declining. One patient was admitted to the hospital during the infection and subsequently died.

CONCLUSION: RSV may cause outbreaks in LTCFs that traditional diagnostic methods do not detect. RT‐PCR can provide a more timely and accurate diagnosis of outbreaks, which allows for early symptomatic treatment, rational use of antibiotics, and improved infection control.
Matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry for genotyping of human platelet‐specific antigens
Authors: Garritsen Henk S.P. , Fan Alex Xiu‐Cheng , Bosse Nicole , Hannig Horst , Kelsch Reinhard , Kroll Hartmut , Holzgreve Wolfgang , Zhong Xiao Yan
Published: January 2009

BACKGROUND: Genotyping of single‐nucleotide polymorphisms (SNPs) using matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry (MALDI‐TOF MS) is an emerging technique, where finally tools for end users have become available to design primers and analyze SNPs of their own interest. This study investigated the potential of this technique in platelet (PLT) genotyping and developed a validated method for genotyping of clinical relevant human PLT antigens (HPAs).

STUDY DESIGN AND METHODS: A multiplex assay using MALDI‐TOF MS to analyze six HPA loci (HPA‐1, HPA‐2, HPA‐3, HPA‐4, HPA‐5, and HPA‐15) simultaneously in a single reaction was applied for the genotyping of 100 DNA samples from a cohort of plateletpheresis donors and a patient population (n = 20) enriched for rare alleles. The genotyping results using MALDI‐TOF MS were validated by the comparison with the results from typing by polymerase chain reaction with sequence‐specific primers and conventional DNA sequencing.

RESULTS: Both homozygous and heterozygous genotypes of HPA‐1 to ‐5 and ‐15 of the 120 individuals were easily identified by a six‐plexed assay on MALDI‐TOF MS. The three approaches achieved a 100 percent concordance for the genotyping results of the six HPA loci.

CONCLUSION: Compared to conventional methods, the MALDI‐TOF MS showed several advantages, such as a high velocity, the ability to perform multiplexed assays in a single reaction, and automated high‐throughput analysis of samples. This enables cost‐efficient large‐scale PLT genotyping for clinical applications.
Human platelets as a substrate source for the in vitro amplification of the abnormal prion protein (PrPSc) associated with variant Creutzfeldt‐Jakob disease
Authors: Jones Michael , Peden Alexander H. , Yull Helen , Wight Darren , Bishop Matthew T. , Prowse Chris V. , Turner Marc L. , Ironside James W. , MacGregor Ian R. , Head Mark W.
Published: January 2009

BACKGROUND: Four recent cases of transfusion‐related transmission of variant Creutzfeldt‐Jakob disease (vCJD) highlight the need to develop a highly sensitive and specific screening test to detect infectivity in the blood of asymptomatic infected individuals. Protein misfolding cyclic amplification (PMCA), a method for the amplification of minute amounts of disease‐associated abnormal prion protein (PrPSc) to readily detectable levels, could be incorporated into such a test provided that a suitable substrate source for routine use in human PMCA reactions can be found.

STUDY DESIGN AND METHODS: With the use of seed sources from individuals with variant and sporadic CJD, the use of human platelets (PLTs) as a PMCA substrate source was evaluated. The effects of seed/substrate prion protein gene (PRNP) codon 129 genotype compatibility on amplification efficiency and freeze‐thaw on a substrate's ability to support amplification and the degree of amplification achieved by serial PMCA (sPMCA) were investigated.

RESULTS: Seed/substrate PRNP codon 129 compatibility was found to have a major influence on PrPSc amplification efficiency. Individual substrates, of the same PRNP codon 129 genotype, could be pooled and stored frozen for use in subsequent PMCA reactions. A consistent 10‐fold increase in PrPSc detection sensitivity was achieved after each round of sPMCA, resulting in a 10,000‐fold increase in detection sensitivity after four rounds, with no evidence of de novo PrPSc production detected in the unseeded PLT substrate.

CONCLUSIONS: Providing issues of seed/substrate PRNP codon 129 compatibility are taken into consideration human PLTs are a suitable, readily available, renewable substrate source for use in human PMCA applications.
Transfusion‐induced serum sickness
Authors: Saegeman Veroniek , Wynendaele Wim , Kerre Stefan , Dedeurwaerdere Franceska , Van den Driessche Marleen , Moerman Jan
Published: January 2009

BACKGROUND: Transfusion‐induced serum sickness reactions are rarely reported in the literature. The Type III hypersensitivity reaction to heterologous proteins involves deposition of complement and immune complexes in small vessel walls resulting in a leukocytoclastic vasculitis. A case of a multiply transfused patient with several episodes of serum sickness reactions is presented.

CASE REPORT: A 61‐year‐old man with myelodysplastic syndrome type refractory anemia presented with fever, rash, and polyarthralgia 5 days after transfusion of red blood cells (RBCs). By transfusing plasma‐free “washed” RBCs, similar serum sickness reactions were avoided.

RESULTS: Laboratory investigation showed an increase of serum creatinine, hematuria, and proteinuria. Levels of circulating immune complexes immunoglobulin G and immunoglobulin M were increased. Hypocomplementemia could not be demonstrated. Histopathologic examination of the skin showed leukocytoclastic vasculitis, compatible with serum sickness.

CONCLUSION: The importance of early recognition of transfusion‐induced serum sickness reactions is emphasized, because this can reduce unnecessary morbidity from this unusual complication of transfusion. To prevent this type of transfusion reaction, patients who experienced serum sickness–like reactions after transfusion should only receive plasma‐free washed RBCs.
Inclusion of Dietary Evaluation in Cardiovascular Disease Risk Prediction Models Increases Accuracy and Reduces Bias of the Estimations
Authors: Panagiotakos Demosthenes B. , Pitsavos Christos , Stefanadis Christodoulos
Published: January 2009

In the past few years, the prediction of CVD risk has received special attention; however, some investigators assert that risk models have so far not been very successful. Thus, we examined whether the inclusion of dietary evaluation in a risk prediction model that already contained the classical CVD risk factors increases the accuracy and reduces the bias in estimating future CVD events. The database of the ATTICA study (which included information from 1,514 men and 1,528 women) was used. At baseline, the HellenicSCORE values (based on age, gender, smoking, systolic blood pressure, and total cholesterol) were calculated, while overall assessment of dietary habits was based on the Mediterranean diet score (MDS) that evaluates adherence to this traditional diet. In 2006, a five‐year follow‐up was performed in 2,101 participants and development of CVD (coronary heart disease, acute coronary syndromes, stroke, or other CVD) was defined according to WHO‐ICD‐10 criteria. The MDS and the HellenicSCORE were significant predictors of CVD events, even after adjusting for various potential confounders (p < 0.05). However, estimating bias (i.e., misclassification of cases) of the model that included HellenicSCORE and other potential confounders was 8.7%. The MDS was associated with the estimating bias of the outcome (p < 0.001) and explained 5.5% of this bias. Other baseline factors associated with bias were increased body mass index, low education status, and increased energy intake/BMR ratio. The inclusion of dietary evaluation, as well as other Sociodemographic and anthropometric characteristics, increases the accuracy and reduces estimating bias of CVD risk prediction models.
The Impact of Joint Responses of Devices in an Airport Security System
Authors: Nie Xiaofeng , Batta Rajan , Drury Colin G. , Lin Li
Published: January 2009

In this article, we consider a model for an airport security system in which the declaration of a threat is based on the joint responses of inspection devices. This is in contrast to the typical system in which each check station independently declares a passenger as having a threat or not having a threat. In our framework the declaration of threat/no‐threat is based upon the passenger scores at the check stations he/she goes through. To do this we use concepts from classification theory in the field of multivariate statistics analysis and focus on the main objective of minimizing the expected cost of misclassification. The corresponding correct classification and misclassification probabilities can be obtained by using a simulation‐based method. After computing the overall false alarm and false clear probabilities, we compare our joint response system with two other independently operated systems. A model that groups passengers in a manner that minimizes the false alarm probability while maintaining the false clear probability within specifications set by a security authority is considered. We also analyze the staffing needs at each check station for such an inspection scheme. An illustrative example is provided along with sensitivity analysis on key model parameters. A discussion is provided on some implementation issues, on the various assumptions made in the analysis, and on potential drawbacks of the approach.
A Comprehensive Network Security Risk Model for Process Control Networks
Authors: Henry Matthew H. , Haimes Yacov Y.
Published: January 2009

The risk of cyber attacks on process control networks (PCN) is receiving significant attention due to the potentially catastrophic extent to which PCN failures can damage the infrastructures and commodity flows that they support. Risk management addresses the coupled problems of (1) reducing the likelihood that cyber attacks would succeed in disrupting PCN operation and (2) reducing the severity of consequences in the event of PCN failure or manipulation. The Network Security Risk Model (NSRM) developed in this article provides a means of evaluating the efficacy of candidate risk management policies by modeling the baseline risk and assessing expectations of risk after the implementation of candidate measures. Where existing risk models fall short of providing adequate insight into the efficacy of candidate risk management policies due to shortcomings in their structure or formulation, the NSRM provides model structure and an associated modeling methodology that captures the relevant dynamics of cyber attacks on PCN for risk analysis. This article develops the NSRM in detail in the context of an illustrative example.
It's SHO Time! Short‐Sale Price Tests and Market Quality
Authors: DIETHER KARL B. , LEE KUAN‐HUI , WERNER INGRID M.
Published: January 2009

We examine the effects of the Securities and Exchange Commission (SEC)‐mandated temporary suspension of short‐sale price tests for a set of Pilot securities. While short‐selling activity increases both for NYSE‐ and Nasdaq‐listed Pilot stocks, returns and volatility at the daily level are unaffected. NYSE‐listed Pilot stocks experience more symmetric trading patterns and a slight increase in spreads and intraday volatility after the suspension while there is a smaller effect on market quality for Nasdaq‐listed Pilot stocks. The results suggest that the effect of the price tests on market quality can largely be attributed to distortions in order flow created by the price tests themselves.
Should Investors Bet on the Jockey or the Horse? Evidence from the Evolution of Firms from Early Business Plans to Public Companies
Authors: KAPLAN STEVEN N. , SENSOY BERK A. , STRÖMBERG PER
Published: January 2009

We study how firm characteristics evolve from early business plan to initial public offering (IPO) to public company for 50 venture capital (VC)‐financed companies. Firm business lines remain remarkably stable while management turnover is substantial. Management turnover is positively related to alienable asset formation. We obtain similar results using all 2004 IPOs, suggesting that our main results are not specific to VC‐backed firms or the time period. The results suggest that, at the margin, investors in start‐ups should place more weight on the business (“the horse”) than on the management team (“the jockey”). The results also inform theories of the firm.
Entrepreneurial Shareholder Activism: Hedge Funds and Other Private Investors
Authors: KLEIN APRIL , ZUR EMANUEL
Published: January 2009

We examine recent confrontational activism campaigns by hedge funds and other private investors. The main parallels between the groups are a significantly positive market reaction for the target firm around the initial Schedule 13D filing date, significantly positive returns over the subsequent year, and the activist's high success rate in achieving its original objective. Further, both activists frequently gain board representation through real or threatened proxy solicitations. Two major differences are that hedge funds target more profitable firms than other activists, and hedge funds address cash flow agency costs whereas other private investors change the target's investment strategies.
Labor and Corporate Governance: International Evidence from Restructuring Decisions
Authors: ATANASSOV JULIAN , KIM E. HAN
Published: January 2009

Our results highlight the importance of interaction among management, labor, and investors in shaping corporate governance. We find that strong union laws protect not only workers but also underperforming managers. Weak investor protection combined with strong union laws are conducive to worker–management alliances, wherein poorly performing firms sell assets to prevent large‐scale layoffs, garnering worker support to retain management. Asset sales in weak investor protection countries lead to further deteriorating performance, whereas in strong investor protection countries they improve performance and lead to more layoffs. Strong union laws are less effective in preventing layoffs when financial leverage is high.
Are Liquidity and Information Risks Priced in the Treasury Bond Market?
Authors: LI HAITAO , WANG JUNBO , WU CHUNCHI , HE YAN
Published: January 2009

We provide a comprehensive empirical analysis of the effects of liquidity and information risks on expected returns of Treasury bonds. We focus on the systematic liquidity risk of Pastor and Stambaugh as opposed to the traditional microstructure‐based measures of liquidity. Information risk is measured by the probability of information‐based trading (PIN). We document a strong positive relation between expected Treasury returns and liquidity and information risks, controlling for the effects of other systematic risk factors and bond characteristics. This relation is robust to many empirical specifications and a wide variety of traditional liquidity and informed trading proxies.
Public Information, IPO Price Formation, and Long‐Run Returns: Japanese Evidence
Authors: KUTSUNA KENJI , SMITH JANET KIHOLM , SMITH RICHARD L.
Published: January 2009

The price formation process of JASDAQ IPOs is more transparent than in the United States. The transparency facilitates analysis of important issues in the IPO literature—why offer prices only partially adjust to public information and adjust more fully to negative information, and why adjustments are related to initial returns. The evidence indicates that early price information conveys the underwriter's commitment to compensate investors for acquiring and/or disclosing information. Offer prices reflect pre‐IPO market values of public companies and implicit agreements between underwriters and issuers that originate well before the offering. Underadjustment of offer prices is substantially reversed in the aftermarket.
Does ICD Indication Affect Quality of Life and Levels of Distress?
Authors: PEDERSEN SUSANNE S. , SEARS SAMUEL F. , BURG MATTHEW M. , VAN DEN BROEK KRISTA C.
Published: January 2009

The implantable cardioverter defibrillator (ICD) is the treatment of choice for life‐threatening arrhythmias, with ICD indications having recently been extended to include primary prophylaxis. Despite the medical benefits of the ICD, there is an ongoing debate as to the impact of the ICD on patients’ lives, particularly whether primary prophylaxis implantation may impact adversely on patient‐centered outcomes such as quality of life (QoL) and distress. We examined the evidence for a role of ICD indication on these patient‐centered outcomes. A literature search was conducted on PubMed and Web of Science from 2002 to present, focusing on indication for ICD therapy and patient‐centered outcomes (i.e., anxiety, depression, disease‐specific, or general QoL). We identified five studies (seven articles) concerning the impact of indication on patient‐centered outcomes. Sample sizes varied from 91–426 patients across studies, five of seven articles used a prospective design, and follow‐up ranged from 2–12 months. No study reported an effect for indication on patient‐centered outcomes. There is no evidence to suggest that patients receiving an ICD for primary prophylaxis have subsequent poorer QoL and greater distress than patients receiving an ICD for secondary prophylaxis. This knowledge may help cardiologists in the clinical management of patients, in particular when discussing ICD implantation with patients.
Performance of Dedicated Versus Integrated Bipolar Defibrillator Leads with CRT‐Defibrillators: Results from a Prospective Multicenter Study
Authors: FREEDMAN ROGER A. , PETRAKIAN ALEX , BOYCE KER , HAFFAJEE CHARLES , VAL‐MEJIAS JESUS E. , OZA ASHISH L.
Published: January 2009

Introduction: Right ventricular (RV) anodal stimulation may occur in cardiac resynchronization therapy defibrillators (CRT‐D) when left ventricular (LV) pacing is configured between the LV lead and an electrode on the RV defibrillator lead. RV defibrillator leads can have a dedicated proximal pacing ring electrode (dedicated bipolar) or utilize the distal shocking coil as the proximal pacing electrode (integrated bipolar). This study compares the performance of integrated versus dedicated leads with respect to anodal stimulation incidence, sensing, and inappropriate ventricular tachyarrhythmia detection in patients implanted with CRT‐D.

Methods: Two hundred ninety‐two patients were randomly assigned to receive dedicated or integrated bipolar RV leads at the time of CRT‐D implantation. Patients were followed for 6 months.

Results: Patients with dedicated bipolar RV leads exhibited markedly higher rates of anodal stimulation than did patients with integrated leads. The incidence of anodal stimulation was 64% at implant for dedicated bipolar RV leads compared to 1% for integrated bipolar RV leads. The likelihood of anodal stimulation in patients with dedicated leads fell progressively during the 6‐month follow‐up (51.5%), but always exceeded the incidence of anodal stimulation in patients with integrated leads (5%). Clinically detectable undersensing and oversensing were very unusual and did not differ significantly between lead designs. There were no inappropriate ventricular tachyarrhythmia detections for either lead type.

Conclusion: Integrated bipolar RV defibrillator leads had a significantly lower incidence of RV anodal stimulation when compared to dedicated bipolar RV defibrillation leads, with no clinically detectable oversensing or undersensing, and with no inappropriate ventricular tachyarrhythmia detections for either lead type.
Increased Anxiety in Partners of Patients with a Cardioverter‐Defibrillator: The Role of Indication for ICD Therapy, Shocks, and Personality
Authors: PEDERSEN SUSANNE S. , VAN DEN BERG MARTHA , ERDMAN RUUD A.M. , VAN SON JENNY , JORDAENS LUC , THEUNS DOMINIC A.M.J.
Published: January 2009

Background: The partner of the implantable cardioverter‐defibrillator (ICD) patient serves as an important source of support for the patient, which may be hampered if the partner experiences increased distress. We examined (1) potential differences in anxiety and depressive symptoms in ICD patients compared to their partners, and (2) the extent to which the partner's personality is a more important determinant of partner distress than patient clinical characteristics, using a prospective design.

Methods: Consecutively implanted ICD patients (n = 196) and their partners (n = 196) completed a set of psychological questionnaires at baseline and 6 months after implantation.

Results: Analysis of variance with repeated measures showed that partners had significantly higher levels of anxiety compared to patients (F(1,390) = 16.431; P < 0.001) but not depressive symptoms (F(1,390) = 0.186; P = 0.67). There was a significant overall reduction in anxiety (F(1,390) = 79.552; P < 0.001) and depressive symptoms (F(1,390) = 39.868; P < 0.001) over 6 months, with group (i.e., patient vs partner) exerting a stable effect on anxiety (F(1,390) = 0.966; P = 0.33) and depressive symptoms (F(1,390) = 0.025; P = 0.87). These results remained in adjusted analysis. Determinants of anxiety and depressive symptoms in partners included secondary prophylaxis in patients (Ps < 0.001–0.002), Type D personality of the partner (Ps < 0.001–0.001), secondary prophylaxis by shock interaction (P = 0.002; anxiety only), and secondary prophylaxis by Type D interaction (Ps = 0.001–0.003).

Conclusions: Partners had higher levels of anxiety but not depression than ICD patients. Partner distress could be attributed not only to the partner's personality, but also to patient clinical characteristics, primarily secondary prophylaxis for ICD therapy. These results indicate that information on the clinical characteristics of the patient in addition to partner characteristics may help identify partners at risk of distress.
New or Aggravated Heart Failure during Long‐Term Right Ventricular Pacing after AV Junctional Catheter Ablation
Authors: POÇI DRITAN , BACKMAN LOTTA , KARLSSON THOMAS , EDVARDSSON NILS
Published: January 2009

Background: Atrioventricular junctional ablation (AVJA) improves symptoms and quality of life in patients with pharmacologically resistant atrial fibrillation (AF). However, long‐term right ventricular stimulation has also been reported to lead to deterioration of the left ventricular function. We retrospectively analyzed the incidence of new or aggravated heart failure (HF) during long‐term right ventricular stimulation following AVJA.

Methods: Two hundred thirteen patients (110F:103M), 73 ± 10 years old, were followed for a period of 6 ± 3 years after AVJA. Forty‐nine patients (23%) were known to have HF before AVJA. New HF was diagnosed if at least two of the following criteria were present: NYHA class >2, an LVEF <45%, and medication for HF. Aggravated HF was defined as an increase in the functional class and/or new prescription of medication for HF. All‐cause death was a secondary endpoint.

Results: During follow‐up, 26% of the patients with known HF showed an aggravation of HF, while 13% developed new symptoms of HF. High age and low EF were independent predictors of new or aggravated HF and of new HF, while none of the tested variables predicted aggravation of known HF. The all‐cause mortality was 16%, where high age and coronary artery disease were found to be independent predictors.

Conclusion: AVJA followed by right ventricular pacing was associated with aggravated HF in 23% of patients with known HF, while development of new symptoms of HF occurred much less often during follow‐up (13%). The majority of patients who underwent AVJA continued to do well during long‐term follow‐up.
Outcomes in Adolescents with Postural Orthostatic Tachycardia Syndrome Treated with Midodrine and β‐Blockers
Authors: LAI CINDY C. , FISCHER PHILIP R. , BRANDS CHAD K. , FISHER JENNIFER L. , PORTER CO‐BURN J. , DRISCOLL SHERILYN W. , GRANER KEVIN K.
Published: January 2009

Background: Postural orthostatic tachycardia syndrome (POTS) is associated with debilitating fatigue, dizziness, and discomfort in previously healthy adolescents. The effects of medical therapy have not been well studied in this patient population. This study assessed the relative efficacy and impact of drug therapy on the functioning and quality of life in adolescents with POTS.

Methods: A retrospective, single center, chart review analysis with a follow‐up written survey was conducted on a group of 121 adolescents who had undergone autonomic reflex screening at the Mayo Clinic from 2002 to 2005 as part of an evaluation for possible POTS.

Results: Of 121 surveys sent, 47 adolescents returned a completed survey. In this cohort of patients, the two most commonly prescribed drug therapies were midodrine (n = 13) and β‐blockers (n = 14). Patients in the midodrine group were comparable to patients in the β‐blocker group in gender, age, pretreatment postural heart rate changes, and months from initial evaluation to survey completion. More patients treated with a β‐blocker reported improvement after visiting Mayo Clinic (100% vs 62%, P = 0.016) and more attributed their progress to medication (63.6% vs 36.4%, P = 0.011) than did those treated with midodrine.

Conclusion: Treatment with both midodrine and β‐blockers was associated with overall improvement in POTS patients’ general health; however, adolescents taking β‐blockers were more likely than those taking midodrine to credit the role of medications in their improvement.
Strategies to Minimize the Risk of Esophageal Injury durings Catheter Ablation for Atrial Fibrillation
Authors: BAHNSON TRISTRAM D.
Published: January 2009

Esophageal injury is a rare but serious complication of catheter ablation for atrial fibrillation using radiofrequency energy. Recent studies have begun to identify variables that may determine heat transfer to and thermal injury of the esophagus. There is significant variability in the relationship between the esophagus and left atrium among individuals. New imaging techniques can facilitate assessment of esophagus position relative to intended ablation targets. Strategies to minimize the risk of esophageal injury include avoidance of ablation near the esophagus, titration of RF energy delivery at the posterior left atrial endocardium, and the use of alternative ablation methods.
Coexisting Idiopathic Left Ventricular Tachycardia and Atrioventricular Reentrant Tachycardia in a Patient with Wolff‐Parkinson‐White Syndrome
Authors: LIM HONG EUY , PAK HUI‐NAM , KIM YOUNG‐HOON
Published: January 2009

We report a patient with Wolff‐Parkinson‐White syndrome who presented with two distinct tachycardias that represented atrioventricular reentrant tachycardia utilizing left lateral accessory pathway (AP) and idiopathic left ventricular tachycardia (ILVT). Two tachycardias with a complete separate mechanism occurred spontaneously as well as following atrial or ventricular pacing. Successful ablation of the left AP and ILVT resulted in a cure of the double tachycardia.
The Characteristics of an Abnormal Electrogram on the Atrialized Right Ventricle in a Patient with Ebstein's Anomaly
Authors: SHINOHARA TETSUJI , TSUCHIYA TAKESHI , TAKAHASHI NAOHIKO , SAIKAWA TETSUNORI , YOSHIMATSU HIRONOBU
Published: January 2009

Catheter ablation with the use of radiofrequency energy has been used as a treatment for atrioventricular reciprocating tachycardia in patients with Ebstein's anomaly. However, the success rate in these patients is generally low. We experienced a case in which the decision regarding precise accessory pathway (AP) localization was impaired by the presence of an abnormal electrogram in the atrialized right ventricle (ARV) in a patient with Ebstein's anomaly. After the AP conduction was abolished, the abnormal electrogram was observed behind the ventricular wave in the ARV during sinus rhythm. Furthermore, the interval between ventricular potential and the abnormal electrogram observed in the proximal ARV was longer than that in the distal ARV. We suggest that the abnormal electrogram might represent delayed local ventricular activation, and that the potential conduction might be impaired in the ARV.
Left Atrial Substrate Ablation in Addition to Pulmonary Vein Isolation in Paroxysmal Atrial Fibrillation Using a Large 28‐mm Cryoballoon
Authors: OSWALD HANNO , GARDIWAL AJMAL , LÜSEBRINK ULRICH , KLEIN GUNNAR
Published: January 2009

We report a case of successful isolation of all pulmonary veins (PV) for symptomatic paroxysmal atrial fibrillation using a 23‐mm cryoballoon with continued paroxysmal atrial fibrillation during a 3‐month follow‐up. Left atrial‐to‐PV‐junction ablation was then performed 3 months after the first procedure using a larger 28‐mm balloon despite unrecovered isolation of all four PV, thereby curing symptomatic atrial fibrillation in this case.
Improved Detection of Differentially Expressed Genes Through Incorporation of Gene Locations
Authors: Xiao Guanghua , Reilly Cavan , Khodursky Arkady B.
Published: January 2009

SummaryIn determining differential expression in cDNA microarray experiments, the expression level of an individual gene is usually assumed to be independent of the expression levels of other genes, but many recent studies have shown that a gene's expression level tends to be similar to that of its neighbors on a chromosome, and differentially expressed (DE) genes are likely to form clusters of similar transcriptional activity along the chromosome. When modeled as a one‐dimensional spatial series, the expression level of genes on the same chromosome frequently exhibit significant spatial correlation, reflecting spatial patterns in transcription. By modeling these spatial correlations, we can obtain improved estimates of transcript levels. Here, we demonstrate the existence of spatial correlations in transcriptional activity in the Escherichia coli (E. coli) chromosome across more than 50 experimental conditions. Based on this finding, we propose a hierarchical Bayesian model that borrows information from neighboring genes to improve the estimation of the expression level of a given gene and hence the detection of DE genes. Furthermore, we extend the model to account for the circular structure of E. coli chromosome and the intergenetic distance between gene neighbors. The simulation studies and analysis of real data examples in E. coli and yeast Saccharomyces cerevisiae show that the proposed method outperforms the commonly used significant analysis of microarray (SAM) t‐statistic in detecting DE genes.
Bayesian Hierarchical Functional Data Analysis Via Contaminated Informative Priors
Authors: Scarpa Bruno , Dunson David B.
Published: January 2009

Summary A variety of flexible approaches have been proposed for functional data analysis, allowing both the mean curve and the distribution about the mean to be unknown. Such methods are most useful when there is limited prior information. Motivated by applications to modeling of temperature curves in the menstrual cycle, this article proposes a flexible approach for incorporating prior information in semiparametric Bayesian analyses of hierarchical functional data. The proposed approach is based on specifying the distribution of functions as a mixture of a parametric hierarchical model and a nonparametric contamination. The parametric component is chosen based on prior knowledge, while the contamination is characterized as a functional Dirichlet process. In the motivating application, the contamination component allows unanticipated curve shapes in unhealthy menstrual cycles. Methods are developed for posterior computation, and the approach is applied to data from a European fecundability study.
Estimation in Semiparametric Transition Measurement Error Models for Longitudinal Data
Authors: Pan Wenqin , Zeng Donglin , Lin Xihong
Published: January 2009

SummaryWe consider semiparametric transition measurement error models for longitudinal data, where one of the covariates is measured with error in transition models, and no distributional assumption is made for the underlying unobserved covariate. An estimating equation approach based on the pseudo conditional score method is proposed. We show the resulting estimators of the regression coefficients are consistent and asymptotically normal. We also discuss the issue of efficiency loss. Simulation studies are conducted to examine the finite‐sample performance of our estimators. The longitudinal AIDS Costs and Services Utilization Survey data are analyzed for illustration.
The influence of comorbidity on the risk of access‐related bacteremia in chronic hemodialysis patients
Authors: MAZONAKIS Emmanouil , STIRLING Catherine , BOOTH Karen L. , McCLENAHAN Jenny , HERON Neil , GEDDES Colin C.
Published: January 2009

Access‐related bacteremia is an important cause of morbidity in chronic hemodialysis patients. The incidence of bacteremia is higher in patients dialyzing through a tunneled central venous catheter (TCVC) compared with an arteriovenous fistula (AVF). Our aim was to explore if this is explained by patient comorbidity. Two groups of chronic hemodialysis outpatients were compared: all patients who dialyzed through a TCVC at any time during 2003 and were fit enough to subsequently have a functioning AVF or renal transplant even if it was after 2003 (Group 1; n=93); and all patients who dialyzed through a TCVC in 2003 and were not fit enough to have a functioning AVF or renal transplant (Group 2; n=119). Episodes of bacteremia (n=71) were identified and those not related to access were excluded. Patients in Group 1 were younger than Group 2 (57.5 years vs. 64.8 years; P=0.001). The incidences of bacteremia in Groups 1 and 2 were, respectively, 0.31 and 0.44 episodes per 1000 patient days while dialyzing through an AVF (P=0.77), and 2.21 and 2.27 per 1000 days while dialyzing through a TCVC (P=0.91). The 3‐year actual survival from January 1, 2003 to January 1, 2006 was significantly higher in Group 1 than in Group 2 (80.6% vs. 26.1%; P<0.0001) confirming the higher comorbidity of the patients in Group 2. Patients dialyzing through a TCVC (compared with an AVF) have a significantly higher risk of access‐related bacteremia, irrespective of comorbidity.
Quality of life is not related with liver disease severity but with anemia, malnutrition, and depression in HCV‐infected hemodialysis patients
Authors: AFSAR Baris , OZDEMIR Nurhan Fatma , SEZER Siren , HABERAL Mehmet
Published: January 2009

Hepatitis C virus (HCV) infection may deteriorate quality of life. The relationship between HCV infection and quality of life in hemodialysis (HD) patients is unknown. The demographic characteristics, comorbidities, biochemical parameters, and Malnutrition‐Inflammation Score (MIS) were recorded. Child‐Pugh classification, Beck Depression Inventory, and SF‐36 were performed. Liver histopathology was examined. Thirty‐two patients (21 Child‐Pugh‐A, 11 Child‐Pugh‐B) were included. There was high‐grade portal necroinflammatory activity in 14, high‐grade lobular necroinflammatory activity in 26, and hepatic fibrosis in 19 patients. Three patients had cirrhosis. Patients with a high stage of liver fibrosis had lower social functioning scores than patient with a low stage of fibrosis (P= 0.011). The only correlation was between aspartate aminotransferase and the physical function subscale (r=−0.395, P= 0.025). None of the SF‐36 scores differed between Child‐Pugh A and B patients. Instead, most of the SF‐36 subscale and summary scores were related with hemoglobin, albumin, MIS and Beck Depression Score. Quality of life in HCV‐infected HD patients was independent of liver disease severity anchors, but was correlated with anemia, malnutrition, and depression.