bluuebunny/crossref_metadata_2025 huggingface dataset:
IRT Modeling of Tutor Performance to Predict End-of-Year Exam Scores
Authors: Ayers Elizabeth , Junker Brian
Published: May 2008

Interest in end-of-year accountability exams has increased dramatically since the passing of the No Child Left Behind Act in 2001. With this increased interest comes a desire to use student data collected throughout the year to estimate student proficiency and predict how well they will perform on end-of-year exams. This article uses student performance on the Assistment System, an online mathematics tutor, to show that replacing percentage correct with an Item Response Theory estimate of student proficiency leads to better fitting prediction models. In addition, it uses other tutor performance metrics to further increase prediction accuracy. Prediction error bounds are also calculated to attain an absolute measure to which the models can be compared.
Approximate Sample Size Formulas for Testing Group Mean Differences When Variances Are Unequal in One-Way ANOVA
Authors: Guo Jiin-Huarng , Luh Wei-Ming
Published: May 2008

This study proposes an approach for determining appropriate sample size for Welch's F test when unequal variances are expected. Given a certain maximum deviation in population means and using the quantile of F and t distributions, there is no need to specify a noncentrality parameter and it is easy to estimate the approximate sample size needed for heterogeneous one-way ANOVA. The theoretical results are validated by a comparison to the results from a Monte Carlo simulation. Simulation results for the empirical power indicate that the sample size needed by the proposed formulas can almost always achieve the desired power level when Welch's F test is applied to data that are conditionally nonnormal and heterogeneous. Two illustrative examples of the use of the proposed procedure are given to calculate balanced and optimal sample sizes, respectively. Moreover, three sample size tables for two-, four-, and six-group problems are provided, respectively, for practitioners.
Configural, Metric, and Scalar Invariance of the Modified Achievement Goal Questionnaire Across African American and White University Students
Authors: Campbell Hilary L. , Barry Carol L. , Joe Jilliam N. , Finney Sara J.
Published: May 2008

There has been growing interest in comparing achievement goal orientations across ethnic groups. Such comparisons, however, cannot be made until validity evidence has been collected to support the use of an achievement goal orientation instrument for that purpose. Therefore, this study investigates the measurement invariance of a particular measure of achievement goal orientation, the modified Achievement Goal Questionnaire (AGQ-M), across African American and White university students. Confirmatory factor analyses support measurement invariance across the two groups. These findings provide additional validity evidence for the newly conceptualized 2 × 2 framework of achievement goal orientation and for the equivalence of functioning of the AGQ-M across these distinct groups. Because this level of invariance is established, researchers can make more valid inferences about differences in the AGQ-M scores across African American and White students.
A Confirmatory Factor Analysis of Cross Racial Identity Scale (CRIS) Scores
Authors: Worrell Frank C. , Watson Stevie
Published: May 2008

In this study, the authors tested the viability of the expanded nigrescence (NT-E) model as operationalized by Cross Racial Identity Scale (CRIS) scores using confirmatory factor analyses. Participants were 594 Black college students from the Southeastern United States. Results indicated a good fit for NT-E's proposed six-factor structure. One-factor and two-factor higher-order models also yielded good fit indices, although several coefficients in the one-factor higher-order model were not salient or statistically significant. In sum, the results provide strong support for the CRIS as an operationalization of NT-E. The authors suggest that CRIS scores can be used in studies concerned with drawing inferences about the effects of racial identity attitudes.
Discrete Event Modeling and Simulation of Wireless Sensor Network Performance
Authors: Antoine-Santoni T. , Santucci J.F. , De Gentili E. , Costa B.
Published: May 2008

The wireless distributed microsensor networks have profited from recent technological advances and it seems essential to precisely understand these systems. Modeling and simulation appear to be an essential aspect of predicting the Wireless Sensor Network (WSN) specific behavior under different conditions. We want to provide a new method of modeling, simulation and visualization of WSN using a discrete-event approach. Described by Zeigler in the 1970's, the Discrete Event System Specification is ideal for describing the asynchronous nature of the events occuring in WSN. We have provided a basic model for the analysis of WSN performance, including routing management, energy consumption and relative CPU activity. Our approach uses a detailed definition of node-oriented components and aims to introduce methods of visualizing the network at a different level of abstraction.
A Secure and Energy-Efficient Scheme for Group-Based Routing in Heterogeneous Ad Hoc Sensor Networks and Its Simulation Analysis
Authors: Ramachandran Chandrasekar , Obaidat Mohammad S. , Misra Sudip , Peña-Mora Feniosky
Published: May 2008

We present Fuzzy Group-Based Routing Algorithm (FGRA), a secure, energy-efficient scheme for routing in sensor networks. In this scheme, we consider the formation of multipaths for routing. Using fuzzy logic for generating decisions of forwarding or withholding packets, we show that our scheme is robust, efficient and scalable for a large number of nodes. In our scheme, routing takes place with the help of groups of nodes, which includes situations when the nodes are disconnected. We incorporate security in the design of our routing algorithm by using a mobile-agents-based approach. Our scheme is data-centric where named data packets are considered as the focal point of the system, and in this way it can be adapted for any application. We perform some simulations in NS2, and demonstrate that our scheme shows good performance results with scope for additional research.
What Is Family Diversity? Objective and Interpretive Approaches
Authors: Harris Scott R.
Published: May 2008

This article differentiates two ways of understanding family diversity— objectively and interpretively. The search for objective diversity is rooted in the assumption that there are many different kinds of families in the United States and around the world; the search for interpretive diversity is rooted in the assumption that any given “family” may be described in different, often contradictory ways. These divergent assumptions can lead relatively objective or interpretive scholars to produce divergent analyses, even as they use seemingly identical concepts to address similar explanatory concerns. Recognizing the difference between objective and interpretive family diversity can help illuminate the distinctive contributions of existing scholarship and open up potential avenues for future research.
The role of sensitizing experiences in music performance anxiety in adolescent musicians
Authors: Osborne Margaret S. , Kenny Dianna T.
Published: May 2008

Aversive performance incidents play a role in the development of some anxiety disorders. The role of sensitizing experiences in the development of music performance anxiety (MPA) in adolescent music students has not yet been explored. Two-hundred-and-ninety-eight music students were asked to provide written descriptions of their worst performance, what happened and how they felt, specifying their age at the time, audience members, and any events that occurred subsequent to the performance. Descriptions were scored according to six domains: situational and behavioural factors, affective, cognitive and somatic symptoms of anxiety, and outcome. Scores were summed to provide a linear scale that was compared with self-reported MPA and standardized trait anxiety scores. MPA was best predicted by trait anxiety and gender. The presence of negative cognitions in the worst experience descriptions improved the prediction of MPA over trait anxiety and gender alone. None of the other factors added to the prediction. Females reported more emotional distress than males and had significantly higher total scores. These findings confirm patterns found in adult performers and across other forms of performance anxiety in children (e.g., test anxiety). This study highlights cognitions as an important element to address in the treatment of MPA in young musicians.
Music genre as cognitive schema: extramusical associations with country and hip-hop music
Authors: Shevy Mark
Published: May 2008

Popular music genre can be considered as a culturally shared cognitive schema consisting of associations between the sound of the music and extramusical concepts. Understanding the similarities and differences in concepts associated with various genres may improve the efficiency with which music is used for communication. Two online experiments presented brief portions of instrumental country or hip-hop music to 284 participants at a large midwestern US university. The first experiment tested for differences between concepts associated with country and hip-hop music. The second experiment examined the ability of the same music genres to influence person perception in regard to those same concepts. Significant differences were found not only in concepts typically used to define the genres, such as ethnicity, rural—urban classification and age, but also in other concepts that play an important role in communication research and persuasion, such as trustworthiness, friendliness and political ideology.
The Effect of Sexual Priming Cues on Emotional Recognition in Nonviolent Child Sexual Abusers
Authors: Oliver Caroline J. , Watson Derrick G. , Gannon Theresa A. , Beech Anthony R.
Published: May 2008

This article describes a study that used a computer-based task to investigate the emotional recognition skills of child sexual abusers. The experiment consisted of two phases (prime and probe) and measured both response time and error rates to facial expressions. The priming phase of the experiment consisted of the presentation of short phrases via computer of either sexual or neutral content. The probe phase of the experiment consisted of the presentation of adult facial expressions depicting either the emotion fear or surprise . Results showed child sexual abusers to be slightly less accurate overall. Furthermore, contrary to prediction, the effect of sexual priming appeared to make child sexual abusers actually better at recognizing fearful faces ( p = .055). This result is discussed in relation to current victim empathy theory and treatment implications for sexual offenders.
Hezekiah's Alleged Cultic Centralization*
Authors: Edelman Diana
Published: May 2008

The recent article in this journal by I. Finkelstein and N. Silberman ( JSOT 30 [2006]: 259-85), in which the authors attempted to establish the historicity of Hezekiah's religious centralization by linking it with archaeological evidence for the closing of shrines at Arad, Beersheba, and Lachish, highlights the need for historians to reconsider this issue. Finkelstein and Silberman's article lacks the mandatory critical evaluation of the biblical text and inappropriately dates selected archaeological evidence to the reign of a specific king. A re-examination of the highly charged issue of cult centralization in the late eighth century BCE is overdue, and this study offers some needed corrections to the analysis of Finkelstein and Silberman and proposes what is considered to be a more cogent understanding of the reality underlying the biblical claim of a cultic centralization undertaken by Hezekiah. This study does not deal with the separate issue of Hezekiah's alleged cultic reform.
Different Historical Trajectories and Family Diversity Among Chinese, Japanese, and Koreans in the United States
Authors: Jeong Yu-Jin , You Hyun-Kyung
Published: May 2008

Chinese, Japanese, and Korean American families in the United States share several similarities, but they should not be interpreted as the sameness. Each group has gone through different immigration trajectories, and family members in a group have had different experiences. To get further knowledge of different family experiences in contemporary U.S. society, the trajectories of the family relationships among different Asian ethnic groups are examined. We specifically look at the time from arrival to World War II, from World War II to the 1960s, and after the 1960s.
Determinants of Divorce in Nineteenth-Century Flanders
Authors: Matthijs Koen , Baerts Anneleen , Van de Putte Bart
Published: May 2008

In 1830, the year Belgium became independent, there were four divorces in Belgium. From about 1870 to 1910, there were about one hundred divorces per year, and since 1910, there have been about 1,000. The aim of this research is to investigate the factors that played a role in the increase in the number of divorces in Belgium in the course of the nineteenth century. The research relates to information from four Flemish municipalities for the period 1800-1913. Results indicate that an explanation of the rising divorce rate can be sought in the psychological and social consequences of the more pronounced shift in marriage, gender, and family expectations. Increasing numbers of women threw themselves more and more into their gender-specific expressive gender role, whereas the objective opportunities and attainability of this role did not increase commensurately. The result was role strain: high marriage and family expectations soon come up against intrinsic limitations. As a result of this, both individual and general frustration increased, and this was an ideal social substratum for facilitating divorce.
Family Caregivers' Future Planning for Younger and Older Adults With Serious Mental Illness (SMI)
Authors: Corsentino Elizabeth A. , Molinari Victor , Gum Amber M. , Roscoe Lori A. , Mills Whitney L.
Published: May 2008

This study examines plans for future caregiving made by family members of younger ( n = 59) and older adults ( n = 16) with serious mental illness (SMI). An online survey was advertised through a newsletter of the National Alliance on Mental Illness. Qualitative analyses yielded four areas of caregiver concern: health of the care recipient over time, ability of caregivers to sustain support, social support available for the care recipient, and financial burden of care. Despite these concerns, few caregivers reported completed plans for future caregiving. One fourth of the caregivers had made no plans, nor had they discussed future caregiving with others. Although most would prefer other relatives to assume care in the event they could not sustain support, these expectations may not be communicated openly. Generating discussion on this pertinent topic has implications for the aging society regarding how best to care for those with SMI and their caregivers.
Are We There Yet? Are We There Yet?
Authors: Conrad Charles , Malphurs Ryan
Published: May 2008

Operating from a perspective suggested by Kenneth Burke's analyses of “scope and reduction,” in this response essay the authors begin by reconsidering the Aristotelian and Burkean rhetorical traditions that dominate contemporary organizational rhetoric research. They argue that both traditions can be applied in ways that reduce rhetoric to technique or to discourse. Both reductions slight the complex dialectical relationships among action, agency, and structure that define rhetorical action. Using this framework, the authors examine the core essays in this special issue, concluding that although they largely avoid problems related to discoursism, they are less successful in avoiding the other form of reductionism, treating rhetoric as technique and rhetor as magician. In a coda, the authors return to the assumptions of the Platonic/Aristotelian tradition, find that it contains ethical assumptions that are problematic in a world dominated by corporate power, and suggest an alternative approach.
Developing the Political Perspective on Technological Change Through Rhetorical Analysis
Authors: Symon Gillian
Published: May 2008

Rhetorical analysis provides a means through which a political perspective on technological change can be developed at a micro-discursive level. Through the analysis of managers' arguments and counterarguments, this article identifies three rhetorical strategies that negotiate the relationship between the technical and the social: attributing the effects of technology; claiming convergent and divergent interests; and constructing identities for self, groups, and the technology. It argues that a rhetorical approach maintains space for agency on the behalf of employees (through the witcraft of argument) and analytical skepticism concerning the reality of technology properties and effects (through counterargument). In addition, it proposes the concept of the argumentative context as a means of bridging the gap between individual and organizational rhetoric.
The Testament of Moses
Authors: Grierson Fiona
Published: May 2008

The Moses fragment discovered by Ceriani in 1861 is the only extant copy of a pseudepigraphon containing Moses' farewell to Joshua and anticipating the end of Moses' life. It is assumed that the end of the manuscript contained Moses' death and burial. This article builds upon Bauckham's reconstructions of the Testament of Moses and Assumption of Moses and Davila's recent methodological probes to discuss which title, if any, can be assigned to the fragment. It also evaluates suggestions of authorship and composition dates, based on the fragment's ideals and references to historical events. Due to the fact that the end of the Moses fragment is no longer in existence, many of these suggestions, while plausible, are almost impossible to verify.
Intersectional Race and Gender Analyses: Why Legal Processes Just Don't Get It
Authors: Marchetti Elena
Published: May 2008

Legal processes, particularly those relating to criminal justice, have frequently been criticized for their inability to accommodate the experiences of racialized women. Recognizing categories of difference is difficult for processes that are framed within an ideology that emphasizes objectivity and universalism. The Australian Royal Commission into Aboriginal Deaths in Custody (RCIADIC) was a quasi-legal entity that investigated 99 Indigenous deaths in custody, as well as the underlying social, cultural and legal issues that may have had a bearing on those deaths. The RCIADIC, like many other legal processes, appears to have been unable to take an intersectional race and gender approach in its analysis. This article uses the RCIADIC inquiry to identify, describe and critically analyse the ways in which the dominant liberal ideology can, at times, operate to exclude racialized women. The reasons identified are based on the opinions and information collected from 48 interviews of people who either worked for the RCIADIC or were in some other way associated with the RCIADIC. The critical analysis presented in this article provides insights into how legal processes remain patriarchal in focus even when embarking on an inquiry about race.
Patterns of Adaptation of Chinese Postgraduate Students in the United Kingdom
Authors: Zhou Yuefang , Todman John
Published: May 2008

International students coming to the United Kingdom have to adapt to academic cultural differences as well as general cultural differences. Questionnaires were administered to 257 Chinese postgraduate students on anticipated and actually experienced difficulties and on perceived differences between Chinese and U.K. academic cultures before departure, soon after arrival, and about 6 months after arrival. Some participants ( n = 45) responded to questionnaires at three stages; others responded at just one or two stages. A sample of the 45 students ( n = 28) were interviewed about their pre-departure expectations and post-arrival experiences. Patterns of adaptation over time differed in relation to general life, social life, and study life. A major finding was the different patterns of specifically academic adaptation of students who came in groups and those who came individually.
The Index of Attitudes Toward Homosexuals 30 Years Later: A Psychometric Study
Authors: Siebert Darcy Clay , Chonody Jill , Rutledge Scott Edward , Killian Michael
Published: May 2008

Objective: The authors report a validation study of the Index of Attitudes toward Homosexuals (IAH) to examine its ongoing usefulness. Method: Students (n = 331) completed surveys anonymously. Exploratory factor analyses were conducted and group differences analyzed. Results: Content validity was established conceptually, and preliminary discriminant validity was established statistically. Factor analyses suggest a shortened 19-item measure (α = .92) with two subscales. Convergent validity was established by comparing the scores on the IAH and another measure of antigay bias. Groups differed on sex, age, religiosity, parenthood, race, and childhood urbanicity. Conclusion: The revised IAH demonstrates sound psychometric properties. It can be useful to evaluate antigay bias, it can prompt discussion, and it can be used as an outcome measure in intervention studies.
Economic Violence To Women and Girls
Authors: Fawole Olufunmilayo I.
Published: May 2008

Most studies on gender-based violence (GBV) have focused on its physical, sexual, and psychological manifestations. This paper seeks to draw attention to the types of economic violence experienced by women, and describes its consequences on health and development. Economic violence experienced included limited access to funds and credit; controlling access to health care, employment, education, including agricultural resources; excluding from financial decision making; and discriminatory traditional laws on inheritance, property rights, and use of communal land. At work women experienced receiving unequal remuneration for work done equal in value to the men's, were overworked and underpaid, and used for unpaid work outside the contractual agreement. Some experienced fraud and theft from some men, illegal confiscation of goods for sale, and unlawful closing down of worksites. At home, some were barred from working by partners; while other men totally abandoned family maintenance to the women. Unfortunately, economic violence results in deepening poverty and compromises educational attainment and developmental opportunities for women. It leads to physical violence, promotes sexual exploitation and the risk of contracting HIV infection, maternal morbidity and mortality, and trafficking of women and girls. Economic abuse may continue even after the woman has left the abusive relationship. There is need for further large-scale studies on economic violence to women. Multi-strategy interventions that promote equity between women and men, provide economic opportunities for women, inform them of their rights, reach out to men and change societal beliefs and attitudes that permit exploitative behavior are urgently required.
Intervention Validity of Social Behavior Rating Scales
Authors: Elliott Stephen N. , Gresham Frank M. , Frank Jennifer L. , Beddow Peter A.
Published: May 2008

The term intervention validity refers to the extent to which assessment results can be used to guide the selection of interventions and evaluation of outcomes. In this article, the authors review the defining attributes of rating scales that distinguish them from other assessment tools, assumptions regarding the use of rating scales to measure children's social behaviors, and features of scale design that promote intervention validity. They argue that integration of a pragmatic theory for problem solution, assessment of socially valid content, and utilization of a reporting framework aligned to known and effective intervention options are essential to promoting intervention validity of rating scale measures. To illustrate, they describe the combined theoretical and empirical approach used to develop the Social Skills Rating System and its recent revision, the Social Skills Improvement System. Ongoing challenges in the integration and monitoring of social skills interventions are discussed, and possible strategies for linking assessment to intervention are described.
Conflicting Epistemologies
Authors: Robbins Rockey R. , Hill Jill , McWhirter Paula T.
Published: May 2008

This case study contributes to the development of a flexible and coherent theory of American Indian psychology. It focuses on mental health psychology in the context of therapy with a 63-year-old traditional Southeastern Woodland woman (Selu). Theoretical constructs of American Indian therapeutic perspectives and needs are postulated, based on the client's and psychologist's interactions over the course of about one hundred counseling sessions over a 2-year period. One of the strengths of this model is that it emerges from a clinical perspective. Different therapeutic techniques are experimented with, used, abandoned, and merged. Hopefully, the following reflections will help therapists to critically consider psychological perspectives and approaches they may use with traditional American Indians or other nonmajority clients.
Temperature dependence of mechanical properties of zinc and Zircaloy measured using miniaturised disc tests
Authors: Hughes G. M. , Flewitt P. E. J.
Published: May 2008

A miniaturised, small punch disc test method has been used to measure the load–displacement curves for a pure polycrystalline zinc and a Zircaloy 4 zirconium based alloy. The latter has a more complex microstructure than the zinc, comprising α phase (hcp) precipitates in a β phase (bcc) matrix. The load–displacement curves have been measured over a range of temperature that spans the ductile to brittle transition, with both yield stress and fracture energy measured from these data. The temperature dependence of the yield strength for each material has been compared with the corresponding bulk value. The temperature dependence of the total fracture energy obtained from the disc specimens provides a measure of the ductile to brittle transition temperature. Values obtained using Charpy impact test energies have been compared with these data empirically. The results demonstrate the benefits of undertaking tests on small specimens to evaluate yield strength, fracture energy, the ductile to brittle transition temperature and to characterise the variation of fracture mode with temperature.
Inactivating Icmt ameliorates K-RAS–induced myeloproliferative disease
Authors: Wahlstrom Annika M. , Cutts Briony A. , Liu Meng , Lindskog Annika , Karlsson Christin , Sjogren Anna-Karin M. , Andersson Karin M. E. , Young Stephen G. , Bergo Martin O.
Published: May 2008

Hyperactive signaling through the RAS proteins is involved in the pathogenesis of many forms of cancer. The RAS proteins and many other intracellular signaling proteins are either farnesylated or geranylgeranylated at a carboxyl-terminal cysteine. That isoprenylcysteine is then carboxyl methylated by isoprenylcysteine carboxyl methyltransferase (ICMT). We previously showed that inactivation of Icmt mislocalizes the RAS proteins away from the plasma membrane and blocks RAS transformation of mouse fibroblasts, suggesting that ICMT could be a therapeutic target. However, nothing is known about the impact of inhibiting ICMT on the development of malignancies in vivo. In the current study, we tested the hypothesis that inactivation of Icmt would inhibit the development or progression of a K-RAS–induced myeloproliferative disease in mice. We found that inactivating Icmt reduced splenomegaly, the number of immature myeloid cells in peripheral blood, and tissue infiltration by myeloid cells. Moreover, in the absence of Icmt, the ability of K-RAS–expressing hematopoietic cells to form colonies in methylcellulose without exogenous growth factors was reduced dramatically. Finally, inactivating Icmt reduced lung tumor development and myeloproliferation phenotypes in a mouse model of K-RAS–induced cancer. We conclude that inactivation of Icmt ameliorates phenotypes of K-RAS–induced malignancies in vivo.
Rituximab blocks binding of radiolabeled anti-CD20 antibodies (Ab) but not radiolabeled anti-CD45 Ab
Authors: Gopal Ajay K. , Press Oliver W. , Wilbur Shani M. , Maloney David G. , Pagel John M.
Published: May 2008

Rituximab therapy is associated with a long in vivo persistence, yet little is known about the effect of circulating rituximab on B-cell non-Hodgkin lymphoma (B-NHL) targeting by the other available anti-CD20 monoclonal antibodies (MoAbs) 131iodine-tositumomab and 90yttrium-ibritumomab tiuxetan. Therefore we assessed the impact of preexisting rituximab on the binding and efficacy of second anti-CD20 MoAbs to B-NHL and determined whether targeting an alternative lymphoma-associated antigen, CD45, could circumvent this effect. We demonstrated that rituximab concentrations as low as 5 μg/mL nearly completely blocked the binding of a second anti-CD20 MoAbs (P < .001), but had no impact on CD45 targeting (P = .89). Serum from patients with distant exposures to rituximab also blocked binding of anti-CD20 MoAbs to patient-derived rituximab-naive B-NHL at concentrations at low as 7 μg/mL, but did not affect CD45 ligation. A mouse xenograft model (Granta, FL-18, Ramos cell lines) showed that rituximab pretreatment significantly reduced B-NHL targeting and tumor control by CD20-directed radioimmunotherapy (RIT), but had no impact on targeting CD45. These findings suggest that circulating rituximab impairs the clinical efficacy of CD20-directed RIT, imply that novel anti-CD20 MoAbs could also face this same limitation, and indicate that CD45 may represent an alternative target for RIT in B-NHL.
Nonclassical anti-C2 domain antibodies are present in patients with factor VIII inhibitors
Authors: Meeks Shannon L. , Healey John F. , Parker Ernest T. , Barrow Rachel T. , Lollar Pete
Published: May 2008

The antihuman factor VIII (fVIII) C2 domain immune response in hemophilia A mice consists of antibodies that can be divided into 5 groups of structural epitopes and 2 groups of functional epitopes. Groups A, AB, and B consist of classical C2 antibodies that inhibit the binding of fVIII to phospholipid and von Willebrand factor. Groups BC and C contain nonclassical C2 antibodies that block the activation of fVIII by thrombin or factor Xa. Group BC antibodies are the most common and display high specific inhibitory activity and type II kinetics. The C2 epitope groups recognized by 26 polyclonal human anti-fVIII inhibitor plasmas were identified by a novel competition enzyme-linked immunosorbent assay using group-specific murine monoclonal antibodies. Most of the anti-C2 inhibitor plasmas inhibited the binding of both classical and nonclassical antibodies. These results suggest that nonclassical anti-C2 antibodies contribute significantly to the pathogenicity of fVIII inhibitors.
Human leukocyte antigens A23, A24, and A32 but not A25 are ligands for KIR3DL1
Authors: Stern Martin , Ruggeri Loredana , Capanni Marusca , Mancusi Antonella , Velardi Andrea
Published: May 2008

Inhibitory killer cell immunoglobulin receptors (KIR) bind to major histocompatibility complex antigens. Concise knowledge of KIR ligands allows prediction of natural killer (NK)–cell alloreactivity after hematopoietic stem cell transplantation. KIR3DL1 binds to the Bw4 epitope on HLA-B antigens. Although the same epitope is also found on 4 HLA-A antigens (HLA-A23/24/25/32), these are not currently regarded as KIR3DL1 ligands. We show that expression of HLA A*2301, A*2402, or A*3201 but not HLA A*2501 protects target cells from lysis by KIR3DL1+ NK cells. KIR3DL1+ NK cells from donors expressing the Bw4 epitope on an HLA-A antigen only are fully functional and capable of lysing Bw4− target cells. HLA A25 differs at amino acid 90, close to the serologic Bw4 epitope, from A23/24/32 and from Bw4+ HLA-B antigens. These data suggest that HLA-A antigens should be taken into consideration when assessing the potential for NK alloreactivity after hematopoietic stem cell transplantation.
DNA vaccination induces WT1-specific T-cell responses with potential clinical relevance
Authors: Chaise Coralie , Buchan Sarah L. , Rice Jason , Marquet Jeanine , Rouard Hélène , Kuentz Mathieu , Vittes Gisella E. , Molinier-Frenkel Valérie , Farcet Jean-Pierre , Stauss Hans J. , Delfau-Larue Marie-Hélène , Stevenson Freda K.
Published: May 2008

The Wilms tumor antigen, WT1, is associated with several human cancers, including leukemia. We evaluated WT1 as an immunotherapeutic target using our proven DNA fusion vaccine design, p.DOM-peptide, encoding a minimal tumor-derived major histocompatibility complex (MHC) class I–binding epitope downstream of a foreign sequence of tetanus toxin. Three p.DOM-peptide vaccines, each encoding a different WT1-derived, HLA-A2–restricted epitope, induced cytotoxic T lymphocytes (CTLs) in humanized transgenic mice expressing chimeric HLA-A2, without affecting hematopoietic stem cells. Mouse CTLs killed human leukemia cells in vitro, indicating peptide processing/presentation. Low numbers of T cells specific for these epitopes have been described in cancer patients. Expanded human T cells specific for each epitope were lytic in vitro. Focusing on human WT137–45–specific cells, the most avid of the murine responses, we demonstrated lysis of primary leukemias, underscoring their clinical relevance. Finally, we showed that these human CTL kill target cells transfected with the relevant p.DOM-peptide DNA vaccine, confirming that WT1-derived epitopes are presented to T cells similarly by tumors and following DNA vaccination. Together, these data link mouse and human studies to suggest that rationally designed DNA vaccines encoding WT1-derived epitopes, particularly WT137–45, have the potential to induce/expand functional tumor-specific cytotoxic responses in cancer patients.
First thalidomide clinical trial in multiple myeloma: a decade
Authors: van Rhee Frits , Dhodapkar Madhav , Shaughnessy John D. , Anaissie Elias , Siegel David , Hoering Antje , Zeldis Jerome , Jenkins Bonnie , Singhal Seema , Mehta Jayesh , Crowley John , Jagannath Sundar , Barlogie Bart
Published: May 2008

The clinical outcomes of 169 patients enrolled in the first clinical trial of thalidomide for advanced or refractory myeloma are updated. Seventeen patients remain alive and 10 are event-free, with a median follow-up of 9.2 years. According to multivariate analysis of pretreatment variables, cytogenetic abnormalities, present in 47% of patients within 3 months of enrollment, and λ light chain isotype both affected overall survival and event-free survival adversely. Forty percent of the 58 patients lacking these 2 unfavorable features, one-half of whom had no disease recurrence, survived at least 6 years, in contrast to fewer than 5% among those with 1 or 2 risk features (P < .001). Patients who had received cumulative thalidomide doses in excess of 42 g in the first 3 months enjoyed superior overall and event-free survival. The poor outcome associated with λ-type myeloma may relate to its overrepresentation in molecularly defined high-risk disease gleaned from studies in newly diagnosed myeloma.
Cyproheptadine displays preclinical activity in myeloma and leukemia
Authors: Mao Xinliang , Liang Sheng-ben , Hurren Rose , Gronda Marcela , Chow Sue , Xu G. Wei , Wang Xiaoming , Zavareh Reza Beheshti , Jamal Nazir , Messner Hans , Hedley David W. , Datti Alessandro , Wrana Jeff L. , Zhu Yuanxiao , Shi Chang-xin , Lee Kyle , Tiedemann Rodger , Trudel Suzanne , Stewart A. Keith , Schimmer Aaron D.
Published: May 2008

D-cyclins are regulators of cell division that act in a complex with cyclin-dependent kinases to commit cells to a program of DNA replication. D-cyclins are overexpressed in many tumors, including multiple myeloma and leukemia, and contribute to disease progression and chemoresistance. To better understand the role and impact of D-cyclins in hematologic malignancies, we conducted a high throughput screen for inhibitors of the cyclin D2 promoter and identified the drug cyproheptadine. In myeloma and leukemia cells, cyproheptadine decreased expression of cyclins D1, D2, and D3 and arrested these cells in the G0/G1 phase. After D-cyclin suppression, cyproheptadine induced apoptosis in myeloma and leukemia cell lines and primary patient samples preferentially over normal hematopoietic cells. In mouse models of myeloma and leukemia, cyproheptadine inhibited tumor growth without significant toxicity. Cyproheptadine-induced apoptosis was preceded by activation of the mitochondrial pathway of caspase activation and was independent of the drug's known activity as an H1 histamine and serotonin receptor antagonist. Thus, cyproheptadine represents a lead for a novel therapeutic agent for the treatment of malignancy. Because the drug is well tolerated and already approved in multiple countries for clinical use as an antihistamine and appetite stimulant, it could be moved directly into clinical trials for cancer.
Evolutionary origin of regulatory regions of retrogenes in Drosophila
Authors: Bai Yongsheng , Casola Claudio , Betrán Esther
Published: May 2008

Background

Retrogenes are processed copies of other genes. This duplication mechanism produces a copy of the parental gene that should not contain introns, and usually does not contain cis-regulatory regions. Here, we computationally address the evolutionary origin of promoter and other cis-regulatory regions in retrogenes using a total of 94 Drosophila retroposition events we recently identified. Previous tissue expression data has revealed that a large fraction of these retrogenes are specifically and/or highly expressed in adult testes of Drosophila.

Results

In this work, we infer that retrogenes do not generally carry regulatory regions from aberrant upstream or normal transcripts of their parental genes, and that expression patterns of neighboring genes are not consistently shared by retrogenes. Additionally, transposable elements do not appear to substantially provide regulatory regions to retrogenes. Interestingly, we find that there is an excess of retrogenes in male testis neighborhoods that is not explained by insertional biases of the retroelement machinery used for retroposition.

Conclusion

We conclude that retrogenes' regulatory regions mostly do not represent a random set of existing regulatory regions. On the contrary, our conclusion is that selection is likely to have played an important role in the persistence of autosomal testis biased retrogenes. Selection in favor of retrogenes inserted in male testis neighborhoods and at the sequence level to produce testis expression is postulated to have occurred.
Pectic homogalacturonan masks abundant sets of xyloglucan epitopes in plant cell walls
Authors: Marcus Susan E , Verhertbruggen Yves , Hervé Cécile , Ordaz-Ortiz José J , Farkas Vladimir , Pedersen Henriette L , Willats William GT , Knox J Paul
Published: May 2008

Background

Molecular probes are required to detect cell wall polymers in-situ to aid understanding of their cell biology and several studies have shown that cell wall epitopes have restricted occurrences across sections of plant organs indicating that cell wall structure is highly developmentally regulated. Xyloglucan is the major hemicellulose or cross-linking glycan of the primary cell walls of dicotyledons although little is known of its occurrence or functions in relation to cell development and cell wall microstructure.

Results

Using a neoglycoprotein approach, in which a XXXG heptasaccharide of tamarind seed xyloglucan was coupled to BSA to produce an immunogen, we have generated a rat monoclonal antibody (designated LM15) to the XXXG structural motif of xyloglucans. The specificity of LM15 has been confirmed by the analysis of LM15 binding using glycan microarrays and oligosaccharide hapten inhibition of binding studies. The use of LM15 for the analysis of xyloglucan in the cell walls of tamarind and nasturtium seeds, in which xyloglucan occurs as a storage polysaccharide, indicated that the LM15 xyloglucan epitope occurs throughout the thickened cell walls of the tamarind seed and in the outer regions, adjacent to middle lamellae, of the thickened cell walls of the nasturtium seed. Immunofluorescence analysis of LM15 binding to sections of tobacco and pea stem internodes indicated that the xyloglucan epitope was restricted to a few cell types in these organs. Enzymatic removal of pectic homogalacturonan from equivalent sections resulted in the abundant detection of distinct patterns of the LM15 xyloglucan epitope across these organs and a diversity of occurrences in relation to the cell wall microstructure of a range of cell types.

Conclusion

These observations support ideas that xyloglucan is associated with pectin in plant cell walls. They also indicate that documented patterns of cell wall epitopes in relation to cell development and cell differentiation may need to be re-considered in relation to the potential masking of cell wall epitopes by other cell wall components.
Surgeons' beliefs and perceptions about removal of orthopaedic implants
Authors: Hanson Beate , van der Werken Chris , Stengel Dirk
Published: May 2008

Background

The routine removal of orthopaedic fixation devices after fracture healing remains an issue of debate. There are no evidence-based guidelines on this matter, and little is known on surgeons' practice and perceived effectiveness of implant removal in different clinical settings.

Methods

A 41-item questionnaire was distributed to 730 attendees of the AO Principles and Masters Courses of Operative Fracture Treatment in Davos, Switzerland, to assess their attitudes towards removal of different types of implants, and perceived benefits and risks with this common procedure.

Results

The response rate was 655/730 (89.7%), representing 54.6% of all 1199 course attendees. Surgeons from 65 countries (571 males and 84 females, mean age 39 ± SD 9 years) took part in the survey. Fifty-eight percent of the participants did not agree that routine implant removal is necessary, and 49% and 58% did not agree that indwelling implants pose an excess risk for fractures or general adverse effects. Forty-eight percent felt that removal is riskier than leaving the implant in situ. Implant removal in symptomatic patients was rated to be moderately effective (mean rating on a 10-point-scale, 5.8, 95% confidence interval 5.7–6.0). Eighty-five percent of all participants agreed that implant removal poses a burden to hospital resources. Surgeons were undetermined whether implant removal is adequately reimbursed by payers of health care services (44% "I-don't-know"-answers).

Conclusion

Many surgeons refuse a routine implant removal policy, and do not believe in clinically significant adverse effects of retained metal implants. Given the frequency of the procedure in orthopaedic departments worldwide, there is an urgent need for a large randomized trial to determine the efficacy and effectiveness of implant removal with regard to patient-centred outcomes.
Factors affecting medical students in formulating their specialty preferences in Jordan
Authors: Khader Yousef , Al-Zoubi Dema , Amarin Zouhair , Alkafagei Ahmad , Khasawneh Mohammad , Burgan Samar , El Salem Khalid , Omari Mousa
Published: May 2008

Background

In recent years there has been a growing appreciation of the issues of career preference in medicine as it may affect student learning and academic performance. However, no such studies have been undertaken in medical schools in Jordan. Therefore, we carried out this study to investigate the career preferences of medical students at Jordan University of Science and Technology and determine factors that might influence their career decisions.

Methods

A cross-sectional questionnaire-based survey was carried out among second, fourth and sixth year medical students at the Jordan University of Science and Technology, Irbid, Jordan during the academic year 2006/2007. A total of 440 students answered the questionnaire which covered demographic characteristics, specialty preferences, and the factors that influenced these career preferences. Possible influences were selected on the basis of a literature review and discussions with groups of medical students and physicians. Students were asked to consider 14 specialty options and select the most preferred career preference.

Results

The most preferred specialty expressed by male students was surgery, followed by internal medicine and orthopaedics, while the specialty most preferred by female students was obstetrics and gynaecology, followed by pediatrics and surgery. Students showed little interest in orthopedics, ophthalmology, and dermatology. While 3.1% of females expressed interest in anesthesiology, no male students did. Other specialties were less attractive to most students.

Intellectual content of the specialty and the individual's competencies were the most influential on their preference of specialty. Other influential factors were the "reputation of the specialty", "anticipated income", and "focus on urgent care".

Conclusion

Surgery, internal medicine, pediatrics, and obstetrics and gynaecology were the most preferred specialty preferences of medical students at Jordan University of Science and Technology.
Myeloid cell differentiation in response to calcitriol for expressionCD11bandCD14is regulated by myeloid zinc finger-1 protein downstream of phosphatidylinositol 3-kinase
Authors: Moeenrezakhanlou Alireza , Shephard Lindsay , Lam Lucia , Reiner Neil E
Published: May 2008

Immature cells of the mononuclear phagocyte series differentiate in response to calcitriol. This is accompanied by increased expression of both CD11b and CD14 and has been shown to be phosphatidylinositol 3-kinase (PI3K) dependent. The events downstream of PI3K that regulate mononuclear phagocyte gene expression, however, remain to be fully understood. In the present study, we show that incubation of THP-1 cells with calcitriol brings about activation of the myeloid zinc finger-1 (MZF-1) transcription factor dependent upon PI3K. In addition, we show that the proximal promoter regions of both CD11b and CD14 contain functional MZF-1 binding sites that are calcitriol responsive. Site-directed mutagenesis of the putative MZF-1 elements abolished MZF-1 binding to the promoters of both CD11b and CD14. Not only did calcitriol treatment increase MZF-1 DNA binding activity to these sites, but it also up-regulated cellular levels of MZF-1. Silencing of MZF-1 resulted in a markedly blunted response to calcitriol for induction of both CD11b and CD14 mRNA transcript levels. Cell surface expression of CD11b and CD14 was also reduced, but to a lesser extent. Taken together, these results show that MZF-1 is involved downstream of PI3K in a calcitriol-induced signaling pathway leading to myeloid cell differentiation and activation of CD11b and CD14.