bluuebunny/crossref_metadata_2025 huggingface dataset:
Guidelines for Managing Life‐Threatening Food Allergies in Massachusetts Schools
Authors: Sheetz Anne H. , Goldman Patricia G. , Millett Kathleen , Franks Jane C. , Mclntyre C. Lynne , Carroll Constance R. , Gorak Diane , Harrison Christanne Smith , Carrick Michele Abu
Published: October 2009

ABSTRACT: During the past decade, prevalence of food allergies among children increased. Caring for children with life‐threatening food allergies has become a major challenge for school personnel. Prior to 2002, Massachusetts did not provide clear guidelines to assist schools in providing a safe environment for these children and preparing for an emergency response to unintended allergic reactions. In 2001, the Asthma and Allergy Foundation of America/New England Chapter, Massachusetts Department of Education, Massachusetts Department of Public Health, Massachusetts School Nurse Organization, parents, and other professional organizations forged a successful collaboration to develop guidelines for managing life‐ threatening food allergies in schools. The guidelines assist schools by providing information on food allergies and anaphylaxis, emphasizing the need for team planning and development of an individualized health care plan, giving guidance on strategies to prevent accidental exposure to specific allergens in school settings, and offering information on emergency responses should unintended exposures occur. The collaborative process for developing the guidelines, which continued during the distribution and implementation phases, set a tone for successful multidisciplinary teamwork in local schools.
Adolescent and Parent Assessments of Diabetes Mellitus Management at School
Authors: Hayes‐Bohn Rachel , Neumark‐Sztainer Dianne , Mellin Alison , Patterson Joan
Published: October 2009

ABSTRACT: This study explored opinions, concerns, and recommendations regarding care of Type 1 diabetes in schools. Thirty adolescent females and their parents participated in semi‐ structured, individual interviews that were audiotaped, transcribed, coded, and qualitatively analyzed. Responses emerged in three categories: knowledge/training of school staff; foods offered/available at school; and school rules. Participants expressed concerns that school personnel, particularly classroom teachers, possess limited knowledge of diabetes; that healthy food/beverage options are limited in the cafeteria, vending machines, and classrooms; and that school rules impede self‐care of diabetes. Implications for enhancing diabetes management at school are noted. (J Sch Health. 2004;74(5): 166–169)
Attempted Suicide and Associated Health Risk Behaviors Among Native American High School Students
Authors: Shaughnessy Lana , Doshi Sonal R. , Jones Sherry Everett
Published: October 2009

ABSTRACT: Suicide represents the second‐leading cause of death among American Indian/Alaska Native (Al/AN) youth aged 15–24 years. Data from the 2001 Bureau of Indian Affairs (BIA) Youth Risk Behavior Survey were used to examine the association between attempted suicide among high school students and unintentional injury and violence behaviors, sexual risk behaviors, tobacco use, and alcohol and other drug use. The study included students in BIA‐funded high schools with 10 or more students enrolled in grades 9–12. Overall, 16% of BIA high school students attempted suicide one or more times in the 12 months preceding the survey. Females and males who attempted suicide were more likely than females and males who did not attempt suicide to engage in every risk behavior analyzed: unintentional injury and violence behaviors, sexual risk behaviors, tobacco use, and alcohol and other drug use. These data enable educators, school health professionals, and others who work with this population to better identify American Indian youth at risk for attempting suicide bv recognizing the number and variety of health risk behaviors associated with attempted suicide.
Building a Partnership to Evaluate School‐Linked Health Services: The Cincinnati School Health Demonstration Project
Authors: Rose Barbara L. , Mansour Mona , Kohake Kelli
Published: October 2009

ABSTRACT: The Cincinnati School Health Demonstration Project was a 3‐year collaboration that evaluated school‐linked health services in 6 urban elementary (kindergarten to eighth grade) schools. Partners from the Cincinnati Health Department, Cincinnati Public Schools, Cincinnati Children's Hospital Medical Center, and The Health Foundation of Greater Cincinnati wanted to determine if levels of school‐linked care made a difference in student quality of life, school connectedness, attendance, emergency department use, and volume of referrals to health care specialists. School nurses, principals and school staff, parents and students, upper‐level managers, and health service researchers worked together over a 2.5‐year period to learn about and use new technology to collect information on student health, well‐being, and outcome measures. Varying levels of school health care intervention models were instituted and evaluated. A standard model of care was compared with 2 models of enhanced care and service. The information collected from students, parents, nurses, and the school system provided a rich database on the health of urban children. School facilities, staffing, and computer technology, relationship building among stakeholders, extensive communication, and high student mobility were factors that influenced success and findings of the project. Funding for district‐wide computerization and addition of school health staff was not secured by the end of the demonstration project; however, relationships among the partners endured and paved the way for future collaborations designed to better serve urban school children in Cincinnati.
Preferences for Third‐Party Help in Workplace Conflict: A Cross‐Cultural Comparison of Chinese and Dutch Employees
Authors: Giebels Ellen , Yang Huadong
Published: October 2009

This study examines conflict parties’ preferences for different types of third‐party help and how this may be influenced by cultural differences in terms of individualism/collectivism. We focus our analysis on process‐related nonsubstantive help and identify three types of third‐party help in interpersonal conflict situations: relational help, procedural help, and emotional help. In a pilot study with Chinese and Dutch students (N = 93), we first developed and validated three new scales to measure preferences for the three types of third‐party help. To further test specific hypotheses we used another sample of Dutch and Hong Kong Chinese bank employees (N = 71). In line with our expectations, Chinese employees report a higher preference for relational help, while Dutch employees report a higher preference for emotional help. In terms of procedural help, there was no significant difference between Dutch and Chinese employees. Furthermore, additional analyses revealed a gender effect on the preference for emotional help, showing that—regardless of their cultural background—females prefer this type of third‐party help more, presumably because they experience more conflict stress.
Quantifying the Quality of Mediation Agreements
Authors: Poitras Jean , Le Tareau Aurélia
Published: October 2009

For workplace mediation programs, success is most often measured by assessing the agreement rate. However, it is unlikely that all signed agreements are of equal quality. Starting with the principle that the “success” of a mediation program cannot be limited to its agreement rate, we designed a study to assess the quality of mediation agreements. This article uses a questionnaire based on a five‐dimension framework (mediator’s usefulness, procedural justice, satisfaction with agreement, confidence in agreement, and reconciliation between parties) to conduct a cluster analysis of a sample of agreements from a governmental mediation program. Three types of agreement are identified: disappointing, satisfactory, and value‐added agreements. The study’s theoretical contributions as well as its practical implications for mediators and mediation programs are discussed.
Reducing urban demand for wild animals in Vietnam: examining the potential of wildlife farming as a conservation tool
Authors: Drury Rebecca
Published: October 2009

Vietnam is an established thoroughfare for illegal trade in wildlife and growing urban prosperity is believed to be increasing domestic demand for wild animal products and for wild meat in particular. While the debate about the potential for wildlife farming to reduce incentives to hunt and trade continues, the findings of this study (based on data collected through semistructured interviews with the central Hanoi population) demonstrate that farming is not an effective tool in reducing demand for illegal wildlife products and may in fact stimulate greater demand for wild‐caught products. In this context, conservation policy should seek to prevent listed species being farmed for consumption as wild meat; to reduce consumer demand for wild meat through marketing campaigns developed by social marketing experts and based on an in‐depth understanding of the drivers of consumer demand garnered using appropriate social science research methods; and to continue strengthening regulation and enforcement actions preventing illegal trade in wild species.
Microsecond Simulations of Spontaneous Methane Hydrate Nucleation and Growth
Authors: Walsh Matthew R. , Koh Carolyn A. , Sloan E. Dendy , Sum Amadeu K. , Wu David T.
Published: October 2009

Methane's Path to Captivity

The mutual repulsion of oil and water is well known. It is thus somewhat baffling that in arctic regions and in marine sediments, enormous quantities of methane lie trapped under pressure in surrounding cages of ice.

Walsh
et al.

(p.
1095
, published online 8 October; see the Perspective by

Debenedetti and Sarupria

) undertook extended simulations to probe the steps that guide these two normally incompatible molecules along convergent, rather than divergent, paths. Computed 2- and 5-microsecond trajectories trace the process of methane capture as ice crystals nucleate and ultimately assemble into a cage network.
Detection of an Infectious Retrovirus, XMRV, in Blood Cells of Patients with Chronic Fatigue Syndrome
Authors: Lombardi Vincent C. , Ruscetti Francis W. , Das Gupta Jaydip , Pfost Max A. , Hagen Kathryn S. , Peterson Daniel L. , Ruscetti Sandra K. , Bagni Rachel K. , Petrow-Sadowski Cari , Gold Bert , Dean Michael , Silverman Robert H. , Mikovits Judy A.
Published: October 2009

Viral Link to Chronic Fatigue

Chronic fatigue syndrome (CFS) is a complex and debilitating disorder that is often linked to immune system dysfunction but whose cause(s) remain mysterious.

Lombardi
et al.

(p.
585
, published online 8 October; see the Perspective by

Coffin and Stoye

) now present a tantalizing new lead. In blood samples from 101 patients with well-documented CFS, over two-thirds (68) contained DNA from a recently described human gammaretrovirus, xenotropic murine leukemia virus–related virus (XMRV), which possesses sequence similarity to a murine leukemia virus. Cell culture assays confirmed that XMRV derived from CFS patient plasma and from T and B lymphocytes was infectious. Although the correlation with CFS is striking, whether the virus plays a causal role in the disorder remains to be determined. Interestingly, nearly 4% of the 218 healthy donors tested were positive for XMRV, which suggests that this virus—whose pathogenic potential is unknown—may be present in a significant proportion of the general population.
A New Virus for Old Diseases?
Authors: Coffin John M. , Stoye Jonathan P.
Published: October 2009

A retrovirus associated with cancer is linked to chronic fatigue syndrome.
BOUNCING UNIVERSE WITH THE NON-MINIMALLY COUPLED SCALAR FIELD AND ITS RECONSTRUCTION
Authors: SADEGHI J. , MILANI F. , AMANI A. R.
Published: October 2009

In this paper we consider a non-minimally coupled scalar field, and show that its equation of state parameter can cross over -1, ω→-1, and bouncing condition. Also we obtain the stability conditions and consider reconstructing for our model.
THE EFFECTS OF THE FOURTH GENERATION IN Bd→ϕKS DECAY
Authors: WANG SHUAI-WEI , LIU YAO-BEI
Published: October 2009

We study the effects of the fourth quark generation model in Bd→ϕKS decay. With the up-to-date experimental data of Br (Bd → ϕKS), SϕKS and AϕKS, we derive the new bound of the new weak phase ϕsb, which is much more stringent than the existing one. At the same time, the theoretical predictions within the SM for Br (Bd → ϕKS), SϕKS and AϕKS agree with the current experimental data within errors.
S AND T PARAMETERS IN THE FERMION CONDENSATE MODEL
Authors: CYNOLTER G. , LENDVAI E. , PÓCSIK G.
Published: October 2009

We calculate the oblique electroweak corrections and confront them with the experiments in a composite Higgs version of the standard model. A vector-like weak doublet and a singlet fermion are added to the standard model without elementary Higgs. Due to quartic coupling, there is a mixing between the components of the new fields triggering electroweak symmetry breaking. The Peskin–Takeuchi S and T electroweak parameters are presented. The new sector of vector-like fermions is slightly constrained, T gives an upper bound on the mixing angle of the new fermions, which is already constrained by self-consistent gap-equations. S gives no constraints on the masses. This extension can give a positive contribution to T, allowing for a heavy Higgs boson in electroweak precision tests of the Standard Model.
INTERNET ICT USE IN AGRICULTURE: MICRO-ENTERPRISES AND SMEs
Authors: BURKE KELLY
Published: October 2009

To date, relatively few studies have examined information and communication technologies (ICT) use in the subset of SMEs known as micro-enterprises. Even fewer have looked at agricultural micro firms. The study presented here compares ICT use among micro-enterprises and SMEs in the agricultural sector. Results indicate extensive use of computers and the Internet, especially for basic ICT functions like email, online purchasing and online business-related research, regardless of firm size. Website ownership is less widespread; larger SMEs are more likely than micro-enterprises to have a website. A number of other ICTs are used similarly by both groups. Among different sized micro-enterprise firms, larger micro-enterprises are more likely than smaller ones to have a website and to conduct financial activities online. However, growth does not result in different adoption rates among micro-enterprises for most internet ICTs. The study also investigates micro-enterprise use of emerging social technologies such as instant messaging, chat, blogging, etc. Perceptions of ICT benefits are also discussed.
Unsupervised models for morpheme segmentation and morphology learning
Authors: Creutz Mathias , Lagus Krista
Published: October 2009

We present a model family called Morfessor for the unsupervised induction of a simple morphology from raw text data. The model is formulated in a probabilistic maximum a posteriori framework. Morfessor can handle highly inflecting and compounding languages where words can consist of lengthy sequences of morphemes. A lexicon of word segments, called
morphs
, is induced from the data. The lexicon stores information about both the usage and form of the morphs. Several instances of the model are evaluated quantitatively in a morpheme segmentation task on different sized sets of Finnish as well as English data. Morfessor is shown to perform very well compared to a widely known benchmark algorithm, in particular on Finnish data.
Impact of intercluster communication mechanisms on ILP in clustered VLIW architectures
Authors: Gangwar Anup , Balakrishnan M. , Kumar Anshul
Published: October 2009

VLIW processors have started gaining acceptance in the embedded systems domain. However, monolithic register file VLIW processors with a large number of functional units are not viable. This is because of the need for a large number of ports to support FU requirements, which makes them expensive and extremely slow. A simple solution is to break the register file into a number of smaller register files with a subset of FUs connected to it. These architectures are termed
clustered VLIW processors
.

In this article, we first build a case for clustered VLIW processors with four or more clusters by showing that the achievable ILP in most of the media applications for a 16 ALU and 8 LD/ST VLIW processor is around 20. We then provide a classification of the intercluster interconnection design space, and show that a large part of this design space is currently unexplored. Next, using our performance evaluation methodology, we evaluate a subset of this design space and show that the most commonly used type of interconnection, RF-to-RF, fails to meet achievable performance by a large factor, while certain other types of interconnections can lower this gap considerably. We also establish that this behavior is heavily application dependent, emphasizing the importance of application-specific architecture exploration. We also present results about the statistical behavior of these different architectures by varying the number of clusters in our framework from 4 to 16. These results clearly show the advantages of one specific architecture over others. Finally, based on our results, we propose a new interconnection network, which should lower this performance gap.
Scan-BIST based on cluster analysis and the encoding of repeating sequences
Authors: Li Lei , Wang Zhanglei , Chakrabarty Krishnendu
Published: October 2009

We present a built-in self-test (BIST) approach for full-scan designs that extracts the most frequently occurring sequences from deterministic test patterns. The extracted sequences are stored on-chip, and are used during test application. Three sets of test patterns are applied to the circuit under test during a BIST test session; these include pseudorandom patterns, semirandom patterns, and deterministic patterns. The semirandom patterns are generated based on the stored sequences and they are more likely to detect hard-to-detect faults than pseudorandom patterns. The deterministic patterns are encoded using either the stored sequences or the LFSR reseeding technique to reduce test data volume. We use the cluster analysis technique for sequence extraction to reduce the amount of data to be stored. Experimental results for the ISCAS-89 benchmark circuits show that the proposed approach often requires less on-chip storage and test data volume than other recent BIST methods.
Workload-ahead-driven online energy minimization techniques for battery-powered embedded systems with time-constraints
Authors: Cai Yuan , Schmitz Marcus T. , Al-Hashimi Bashir M. , Reddy Sudhakar M.
Published: October 2009

This article proposes a new online voltage scaling (VS) technique for battery-powered embedded systems with real-time constraints. The VS technique takes into account the execution times and discharge currents of tasks to further reduce the battery charge consumption when compared to the recently reported slack forwarding technique [Ahmed and Chakrabarti 2004], while maintaining low online complexity of
O
(1). Furthermore, we investigate the impact of online rescheduling and remapping on the battery charge consumption for tasks with data dependency which has not been explicitly addressed in the literature and propose a novel rescheduling/remapping technique. Finally, we take leakage power into consideration and extend the proposed online techniques to include adaptive body biasing (ABB) which is used to reduce the leakage power. We demonstrate and compare the efficiency of the presented techniques using seven real-life benchmarks and numerous automatically generated examples.
Instruction set synthesis with efficient instruction encoding for configurable processors
Authors: Lee Jong-Eun , Choi Kiyoung , Dutt Nikil D.
Published: October 2009

Application-specific instructions can significantly improve the performance, energy-efficiency, and code size of configurable processors. While generating new instructions from application-specific operation patterns has been a common way to improve the instruction set (IS) of a configurable processor, automating the design of ISs for given applications poses new challenges---how to create as well as utilize new instructions in a systematic manner, and how to choose the best set of application-specific instructions considering the various effects the new instructions may have on the data path and the compilation? To address these problems, we present a novel IS synthesis framework that optimizes the IS through an efficient instruction encoding for the given application as well as for the given data path architecture. We first build a library of new instructions created with various encoding alternatives taking into account the data path architecture constraints, and then select the best set of instructions while satisfying the instruction bitwidth constraint. We formulate the problem using integer linear programming and also present an effective heuristic algorithm. Experimental results using our technique generate ISs that show improvements of up to about 40% over the native IS for several application benchmarks running on typical embedded RISC processors.
Conceptual data model-based software size estimation for information systems
Authors: Tan Hee Beng Kuan , Zhao Yuan , Zhang Hongyu
Published: October 2009

Size estimation plays a key role in effort estimation that has a crucial impact on software projects in the software industry. Some information required by existing software sizing methods is difficult to predict in the early stage of software development. A conceptual data model is widely used in the early stage of requirements analysis for information systems. Lines of code (LOC) is a commonly used software size measure. This article proposes a novel LOC estimation method for information systems from their conceptual data models through using a multiple linear regression model. We have validated the proposed method using samples from both the software industry and open-source systems.
Amoeba
Authors: Desai Nirmit , Chopra Amit K. , Singh Munindar P.
Published: October 2009

Business service engagements involve processes that extend across two or more autonomous organizations. Because of regulatory and competitive reasons, requirements for cross-organizational business processes often evolve in subtle ways. The changes may concern the business transactions supported by a process, the organizational structure of the parties participating in the process, or the contextual policies that apply to the process. Current business process modeling approaches handle such changes in an ad hoc manner, and lack a principled means for determining what needs to be changed and where. Cross-organizational settings exacerbate the shortcomings of traditional approaches because changes in one organization can potentially affect the workings of another.

This article describes Amoeba, a methodology for business processes that is based on
business protocols
. Protocols capture the business meaning of interactions among autonomous parties via commitments. Amoeba includes guidelines for (1) specifying cross-organizational processes using business protocols, and (2) handling the evolution of requirements via a novel application of protocol composition. This article evaluates Amoeba using enhancements of a real-life business scenario of auto-insurance claim processing, and an aerospace case study.
Fast XML document filtering by sequencing twig patterns
Authors: Kwon Joonho , Rao Praveen , Moon Bongki , Lee Sukho
Published: October 2009

XML-enabled publish-subscribe (pub-sub) systems have emerged as an increasingly important tool for e-commerce and Internet applications. In a typical pub-sub system, subscribed users specify their interests in a profile expressed in the XPath language. Each new data content is then matched against the user profiles so that the content is delivered only to the interested subscribers. As the number of subscribed users and their profiles can grow very large, the scalability of the service is critical to the success of pub-sub systems. In this article, we propose a novel scalable filtering system called iFiST that transforms user profiles of a twig pattern expressed in XPath into sequences using the Prüfer's method. Consequently, instead of breaking a twig pattern into multiple linear paths and matching them separately, FiST performs
holistic matching
of twig patterns with each incoming document in a
bottom-up
fashion. FiST organizes the sequences into a dynamic hash-based index for efficient filtering, and exploits the commonality among user profiles to enable shared processing during the filtering phase. We demonstrate that the holistic matching approach reduces filtering cost and memory consumption, thereby improving the scalability of FiST.
Detection of corrupted schema mappings in XML data integration systems
Authors: Colazzo Dario , Sartiani Carlo
Published: October 2009

In modern data integration scenarios, many remote data sources are located on the Web and are accessible only through forms or Web services, and no guarantee is given about their stability. In these contexts the detection of corrupted mappings, as a consequence of a change in the source or in the target schema, is a key problem. A corrupted mapping fails in matching the target or the source schema, hence it is not able to transform data conforming to a schema S into data conforming to a schema T, nor it can be used for effective query reformulation.

This article describes a novel technique for maintaining schema mappings in XML data integration systems, based on a notion of mapping correctness relying on the denotational semantics of mappings.
Controlling entity state updates to maintain remote consistency within a distributed interactive application
Authors: Kenny Alan , Mcloone Séamus , Ward Tomás
Published: October 2009

One of the ongoing challenges for Distributed Interactive Applications (DIAs) is balancing the quality of service delivered to the end user with the operational costs involved. In particular the resultant network traffic should be minimized without affecting the end user experience where possible. This article proposes the use of remote feedback as a method of maintaining a desired consistency level within a peer-to-peer DIA. Though many existing techniques attempt to maintain consistency within a DIA, they operate in an open-loop manner and do not take error introduced into the system due to transmission delay into consideration. The goal of the work presented in this article is to transform this open-loop scheme into a closed-loop control system utilizing feedback from the remote users. By incorporating remote error into the systems update paradigm, the Protocol Data Unit (PDU) transmission rate can be dynamically altered to reflect changing network conditions. The performance of the resultant closed-loop control system is presented within.
Extrinsic summarization evaluation
Authors: Murray Gabriel , Kleinbauer Thomas , Poller Peter , Becker Tilman , Renals Steve , Kilgour Jonathan
Published: October 2009

In this work we describe a large-scale extrinsic evaluation of automatic speech summarization technologies for meeting speech. The particular task is a decision audit, wherein a user must satisfy a complex information need, navigating several meetings in order to gain an understanding of how and why a given decision was made. We compare the usefulness of extractive and abstractive technologies in satisfying this information need, and assess the impact of automatic speech recognition (ASR) errors on user performance. We employ several evaluation methods for participant performance, including post-questionnaire data, human subjective and objective judgments, and a detailed analysis of participant browsing behavior. We find that while ASR errors affect user satisfaction on an information retrieval task, users can adapt their browsing behavior to complete the task satisfactorily. Results also indicate that users consider extractive summaries to be intuitive and useful tools for browsing multimodal meeting data. We discuss areas in which automatic summarization techniques can be improved in comparison with gold-standard meeting abstracts.
Hepatic phenotype of liver fatty acid binding protein gene-ablated mice
Authors: Martin Gregory G. , Atshaves Barbara P. , Huang Huan , McIntosh Avery L. , Williams Brad J. , Pai Pei-Jing , Russell David H. , Kier Ann B. , Schroeder Friedhelm
Published: October 2009

Although the function of liver fatty acid binding protein in hepatic fatty acid metabolism has been extensively studied, its potential role in hepatic cholesterol homeostasis is less clear. Although hepatic cholesterol accumulation was initially reported in L-FABP-null female mice, that study was performed with early N2 backcross generation mice. To resolve whether the hepatic cholesterol phenotype in these L-FABP−/−mice was attributable to genetic inhomogeneity, these L-FABP−/−mice were further backcrossed to C57Bl/6 mice up to the N10 (99.9% homogeneity) generation. Hepatic total cholesterol accumulation was observed in female, but not male, L-FABP−/−mice at all (N2, N4, N6, N10) backcross generations examined. The greater total cholesterol was due to increased hepatic levels of both unesterified (free) cholesterol and esterified cholesterol. Altered hepatic cholesterol accumulation correlated directly with L-FABP's ability to bind cholesterol with high affinity as shown by direct L-FABP binding of fluorescent cholesterol analogs (NBD-cholesterol, dansyl-cholesterol), a photoactivatable cholesterol analog [free cholesterol benzophenone (FCBP)], and free cholesterol (circular dichroism, isothermal titration microcalorimetry). One mole of fluorescent sterol was bound per mole of L-FABP. This was confirmed by photo-cross-linking studies with the photoactivatable cholesterol analog FCBP and by isothermal titration calorimetry with free cholesterol, which showed that L-FABP bound only one sterol molecule per L-FABP molecule. In contrast, the hepatic phenotype of male, but not female, L-FABP−/−mice was characterized by decreased hepatic triacylglycerol levels at all backcross generations examined. Taken together, these data support the hypothesis that L-FABP plays a role in physiological regulation of not only hepatic fatty acid metabolism, but also that of hepatic cholesterol.
Cholecystokinin-58 and cholecystokinin-8 exhibit similar actions on calcium signaling, zymogen secretion, and cell fate in murine pancreatic acinar cells
Authors: Criddle David N. , Booth David M. , Mukherjee Rajarshi , McLaughlin Euan , Green Gary M. , Sutton Robert , Petersen Ole H. , Reeve Joseph R.
Published: October 2009

The gastrointestinal hormone CCK exists in various molecular forms, with differences in bioactivity between the well-characterized CCK-8 and larger CCK-58 previously reported. We have compared the effects of these peptides on cytosolic calcium concentration ([Ca2+]c), mitochondrial metabolism, enzyme secretion, and cell fate in murine isolated pancreatic acinar cells using fluorescence confocal microscopy and patch-clamp electrophysiology. CCK-58 (1–10 pM) induced transient, oscillatory increases of [Ca2+]c, which showed apical to basolateral progression and were associated with a rise of mitochondrial NAD(P)H. CCK-58 (10 pM) induced zymogen exocytosis in isolated cells and amylase secretion from isolated cells and whole tissues. Hyperstimulation with supraphysiological CCK-58 (5 nM) induced a single large increase of [Ca2+]cthat declined to a plateau, which remained above the basal level 20 min after application and was dependent on external Ca2+entry. In cells dispersed from the same tissues, CCK-8 induced similar patterns of responses to those of CCK-58, with oscillatory increases of [Ca2+]cat lower (pM) concentrations and sustained responses at 5 nM. CCK-58 and CCK-8 exhibited similar profiles of action on cell death, with increases in necrosis at high CCK-58 and CCK-8 (10 nM) that were not significantly different between peptides. The present experiments indicate that CCK-8 and CCK-58 have essentially identical actions on the acinar cell at high and low agonist concentrations, suggesting an action via the same receptor and that the differences observed in an intact rat model may result from indirect effects of the peptides. Our data strengthen the argument that CCK-58 is an important physiological form of this gastrointestinal hormone.
Hedgehog pathway activation and epithelial-to-mesenchymal transitions during myofibroblastic transformation of rat hepatic cells in culture and cirrhosis
Authors: Choi Steve S. , Omenetti Alessia , Witek Rafal P. , Moylan Cynthia A. , Syn Wing-Kin , Jung Youngmi , Yang Liu , Sudan Debra L. , Sicklick Jason K. , Michelotti Gregory A. , Rojkind Marcos , Diehl Anna Mae
Published: October 2009

Myofibroblastic hepatic stellate cells (MF-HSC) are derived from quiescent hepatic stellate cells (Q-HSC). Q-HSC express certain epithelial cell markers and have been reported to form junctional complexes similar to epithelial cells. We have shown that Hedgehog (Hh) signaling plays a key role in HSC growth. Because Hh ligands regulate epithelial-to-mesenchymal transition (EMT), we determined whether Q-HSC express EMT markers and then assessed whether these markers change as Q-HSC transition into MF-HSC and whether the process is modulated by Hh signaling. Q-HSC were isolated from healthy livers and cultured to promote myofibroblastic transition. Changes in mRNA and protein expression of epithelial and mesenchymal markers, Hh ligands, and target genes were monitored in HSC treated with and without cyclopamine (an Hh inhibitor). Studies were repeated in primary human HSC and clonally derived HSC from a cirrhotic rat. Q-HSC activation in vitro (culture) and in vivo (CCl4-induced cirrhosis) resulted in decreased expression of Hh-interacting protein (Hhip, an Hh antagonist), the EMT inhibitors bone morphogenic protein (BMP-7) and inhibitor of differentiation (Id2), the adherens junction component E-cadherin, and epithelial keratins 7 and 19 and increased expression of Gli2 (an Hh target gene) and mesenchymal markers, including the mesenchyme-associated transcription factors Lhx2 and Msx2, the myofibroblast marker α-smooth muscle actin, and matrix molecules such as collagen. Cyclopamine reverted myofibroblastic transition, reducing mesenchymal gene expression while increasing epithelial markers in rodent and human HSC. We conclude that Hh signaling plays a key role in transition of Q-HSC into MF-HSC. Our findings suggest that Q-HSC are capable of transitioning between epithelial and mesenchymal fates.
Effect of global ischemia and reperfusion during ventricular fibrillation in myopathic human hearts
Authors: Massé Stéphane , Farid Talha , Dorian Paul , Umapathy Karthikeyan , Nair Krishnakumar , Asta John , Ross Heather , Rao Vivek , Sevaptsidis Elias , Nanthakumar Kumaraswamy
Published: October 2009

The effect of lack of global coronary perfusion on myocardial activation rate, wavebreak, and its temporal progression during human ventricular fibrillation (VF) is not known. We tested the hypothesis that global myocardial ischemia decreases activation rate and spatiotemporal organization during VF in myopathic human hearts, while increasing wavebreak, and that a short duration of reperfusion can restore these spatiotemporal changes to baseline levels. The electrograms were acquired during VF in a human Langendorff model using global mapping consisting of two 112-electrode arrays placed on the epicardium and endocardium simultaneously. We found that global myocardial ischemia results in slowing of the global activation rate (combined endo and epi), from 4.89 ± 0.04 Hz. to 3.60 ± 0.04 Hz. during the 200 s of global ischemia (no coronary flow) ( P < 0.01) in eight myopathic hearts. Two minutes of reperfusion contributed to reversal of the slowing with activation rate value increasing close to VF onset (4.72 ± 0.04 Hz). In addition, during the period of ischemia, an activation rate gradient between the endocardium (3.76 ± 0.06 Hz) and epicardium (3.45 ± 0.06 Hz) was observed ( P < 0.01). There was a concomitant difference in wavebreak index (that provides a normalized parameterization of phase singularities) between the epicardium (11.29 ± 2.7) and endocardium (3.25 ± 2.7) during the 200 s of ischemia ( P = 0.02). The activation rate, gradient, and wavebreak changes were reversed by short duration (2 min) of reperfusion. Global myocardial ischemia of 3 min leads to complex spatiotemporal changes during VF in myopathic human hearts; these changes can be reversed by a short duration of reperfusion.
Estrogen replacement therapy in diabetic ovariectomized female rats potentiates postischemic leukocyte adhesion in cerebral venules via a RAGE-related process
Authors: Xu Hao-Liang , Vetri Francesco , Lee Hae-Kyung , Ye Shuhua , Paisansathan Chanannait , Mao Lizhen , Tan Fulong , Pelligrino Dale A.
Published: October 2009

In this study, we tested the hypothesis that the documented transformation of 17β-estradiol (E2) from a counterinflammatory hormone in nondiabetic (ND) rats to a proinflammatory agent in rats with diabetes mellitus (DM) is due to an enhanced contribution from the receptor for advanced glycation end products (RAGE). Rhodamine 6G-labeled leukocytes were observed through a closed cranial window in rats. In vivo pial venular leukocyte adherence and infiltration were measured over 10 h reperfusion after transient forebrain ischemia in DM (streptozotocin) versus ND intact, ovariectomized (OVX), and E2-replaced (for 7–10 days) OVX (OVE) females. The role of RAGE was examined in two ways: 1) RAGE knockdown via topical application of RAGE antisense versus missense oligodeoxynucleotide or 2) intracerebroventricular injection of the RAGE decoy inhibitor, soluble RAGE. Among diabetic rats, the lowest levels of cortical RAGE mRNA and immunoreactivity of the RAGE ligand, AGE, were seen in OVX females, with significantly higher levels exhibited in intact and OVE females. However, results from the analysis of cortical RAGE protein only partially tracked those findings. When comparing ND to DM rats, cortical AGE immunoreactivity was significantly lower in OVE and intact females but similar in OVX rats. In DM rats, the level of postischemic leukocyte adhesion and infiltration (highest to lowest) was OVE > intact >> untreated OVX. In NDs, adhesion was highest in the untreated OVX group. Leukocyte extravasation was observed at >6 h postischemia but only in diabetic OVE and intact females and in ND OVX (untreated) rats. Pretreatment with RAGE antisense-oligodeoxynucleotide or soluble RAGE attenuated postischemic leukocyte adhesion and prevented infiltration but only in the diabetic OVE and intact groups. These results indicate that the exacerbation of postischemic leukocyte adhesion by chronic E2 replacement therapy in diabetic OVX females involves a RAGE-related mechanism. Targeting RAGE may restore the neuroprotective effect of E2 replacement therapy in diabetic females.
Rate-dependent AV nodal refractoriness: a new functional framework based on concurrent effects of basic and pretest cycle length
Authors: Tadros Rafik , Billette Jacques
Published: October 2009

The atrioventricular (AV) node filters atrial impulses. Underlying rate-dependent refractory properties are assessed with the effective (ERPN; longest nonconducted atrial cycle length) and functional (FRPN; shortest His bundle cycle) refractory period determined with premature protocols at different basic rates. Fast rates prolong ERPN and shorten FRPN, but these effects vary with subjects, age, and species. We propose that these opposite and variable effects reflect the net sum of concurrent cumulative and noncumulative effects associated with basic (BCL) and pretest cycle length (PTCL), respectively. To test this hypothesis, we assessed selective and combined effects of five BCL (S1S1) and six PTCL (S1S2) on ERPN, FRPN, and their subintervals (ERPN = A2H2 + H2A3 and FRPN = H2A3 + A3H3, where A is atrium and H is His bundle) with S1S2S3 protocols in six rabbit heart preparations. At control BCL, PTCL shortenings prolonged ERPN (113 ± 12 vs. 101 ± 14 ms, P < 0.01) as a net result of prolonged A2H2 and curtailed H2A3. At control PTCL, BCL shortenings increased ERPN (127 ± 20 vs. 101 ± 14 ms, P < 0.01) by prolonging A2H2. FRPN did not vary with BCL but decreased (163 ± 6 vs. 175 ± 10 ms, P < 0.01) with PTCL that curtailed H2A3. Equal BCL and PTCL shortenings as in standard protocols prolonged ERPN but left FRPN unchanged. Notably, ERPN and FRPN significantly correlated through their H2A3 subinterval. In conclusion, BCL and PTCL are both important determinants of AV nodal refractoriness and together account for rate-induced changes in ERPN and FRPN observed during standard premature protocols. ERPN and FRPN are related variables. Similar functional rules may govern nodal refractory behavior during supraventricular tachyarrhythmias.
High-Density Lipoprotein–Based Contrast Agents for Multimodal Imaging of Atherosclerosis
Authors: Skajaa Torjus , Cormode David P. , Falk Erling , Mulder Willem J.M. , Fisher Edward A. , Fayad Zahi A.
Published: October 2009

Lipoproteins, natural nanoparticles, have a well-recognized biological role and are highly suitable as a platform for delivering imaging agents. The ease with which both the exterior and interior of the particles can be modified permits the creation of multifunctional nanoparticles for imaging as well as the delivery of therapeutics. Importantly, their endogenous nature may make them biocompatible and biodegradable and allows them to avoid the recognition of the reticuloendothelial system. In particular, high-density lipoproteins (HDL) are of interest, because of their small size they can easily cross the endothelium and penetrate the underlying tissue. We summarize here the progress in establishing HDL as a vector for delivering a variety of diagnostically active materials to vulnerable atherosclerotic plaques in mouse models of atherosclerosis. By loading various types of image-enhancing compounds into either the core or surface of HDL, they can be visualized by different imaging modalities (MRI, CT, optical). By rerouting of HDL away from plaque macrophages, imaging of biological processes in diseases besides atherosclerosis may also be achieved.
Effects of Cigarette Smoke Exposure on Clot Dynamics and Fibrin Structure
Authors: Barua Rajat S. , Sy Fridolin , Srikanth Sundararajan , Huang Grace , Javed Usman , Buhari Cyrus , Margosan Dennis , Ambrose John A.
Published: October 2009

Objectives—

The purpose of this study was to examine the effect of cigarette smoke exposure (CSE) on clot dynamics and fibrin architecture and to isolate the relative contribution of platelets and fibrinogen to clot dynamics.

Methods and Results—

From young healthy males smokers (n=34) and nonsmokers (n=34) a baseline blood was drawn, and smokers had another blood draw after smoking 2 regular cigarettes. Using thromboelastography (TEG) the degree of platelet-fibrin interaction was measured. In additional experiments, abciximab (20 μg/mL) was added to the smokers samples (n=27) to reduce the effects of platelet function from the TEG parameters. The maximum clot strength (G) obtained with abciximab measured mainly the contribution of fibrinogen to clot strength (GF). By subtracting GF from G, the contribution of platelets to clot strength (GP) was presumed. A significant difference was found for all TEG parameters between nonsmokers versus postsmoking and pre- versus postsmoking samples. Postsmoking both GF and GP were significantly higher as compared to presmoking. On electron microscopy and turbidity analysis, postsmoking fibrin clots were significantly different compared to presmoking and nonsmoking samples.

Conclusions—

Acute CSE changes clot dynamics and alters fibrin architecture. Both functional changes in fibrinogen and platelets appear to contribute to heightened thrombogenicity after acute CSE.
Progenitor Cells From the Explanted Heart Generate Immunocompatible Myocardium Within the Transplanted Donor Heart
Authors: D'Alessandro David A. , Kajstura Jan , Hosoda Toru , Gatti Alessandro , Bello Ricardo , Mosna Federico , Bardelli Silvana , Zheng Hanqiao , D'Amario Domenico , Padin-Iruegas M. Elena , Carvalho Adriana Bastos , Rota Marcello , Zembala Michael O. , Stern David , Rimoldi Ornella , Urbanek Konrad , Michler Robert E. , Leri Annarosa , Anversa Piero
Published: October 2009

RETRACTION

This article has been retracted:

(
Circ Res
. 2018;123:e00. DOI: 10.1161/RES.0000000000000245.)
Substantial Observer Variability in the Differentiation Between Primary Intracerebral Hemorrhage and Hemorrhagic Transformation of Infarction on CT Brain Imaging
Authors: Lovelock Caroline E. , Anslow Philip , Molyneux Andrew J. , Byrne James V. , Kuker Wilhelm , Pretorius Pieter M. , Coull Andrew , Rothwell Peter M.
Published: October 2009

Background and Purpose—

CT remains the most commonly used imaging technique in acute stroke but is often delayed after minor stroke. Interobserver reliability in distinguishing hemorrhagic transformation of infarction from intracerebral hemorrhage may depend on delays to CT but has not been reported previously despite the clinical importance of this distinction.

Methods—

Initial CT scans with intraparenchymal hematoma from the first 1000 patients with stroke in the Oxford Vascular Study were independently categorized as intracerebral hemorrhage or hemorrhagic transformation of infarction by 5 neuroradiologists, both blinded and unblinded to clinical history. Thirty scans were reviewed twice. Agreement was quantified by the κ statistic.

Results—

Seventy-eight scans showed intraparenchymal hematoma. Blinded pairwise interrater agreements for a diagnosis of intracerebral hemorrhage ranged from κ=0.15 to 0.48 with poor overall agreement (κ=0.35; 95% CI, 0.15 to 0.54) even after unblinding (κ=0.41; 0.21 to 0.60). Blinded intrarater agreements ranged from κ=0.21 to 0.92. Lack of consensus after unblinding was greatest in patients scanned ≥24 hours after stroke onset (67% versus 25%,
P
=0.001) and in minor stroke (National Institutes of Health Stroke Scale ≤5: 56% versus 29%,
P
=0.04) with disagreement in 75% of patients scanned ≥24 hours after minor stroke and in 48% of all 30-day stroke survivors in whom reliable diagnosis would be expected to influence long-term management.

Conclusion—

Reliability of diagnosis of intraparenchymal hematoma on CT brain scan in minor stroke is poor, particularly if scanning is delayed. Immediate brain imaging is justified in patients with minor stroke.