bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intrinsic Toxicity of Hemoglobin: How to Counteract It
Authors: Simoni Jan , Simoni Grace , Moeller John F. 
Published: January 2009

AbstractThe 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

AbstractHemoglobin 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

AbstractLiposome‐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

AbstractThe 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.
It's SHO Time! Short‐Sale Price Tests and Market Quality
Authors: DIETHER KARL B. , LEE KUAN‐HUI , WERNER INGRID M. 
Published: January 2009

ABSTRACTWe 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

ABSTRACTWe 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

ABSTRACTWe 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

ABSTRACTOur 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

ABSTRACTWe 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

ABSTRACTThe 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.
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.