bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissection of Nod factor signalling in legumes: cell biology, mutants and pharmacological approaches
Authors: Esseling J. J. , Emons A. M. C.
Published: April 2004

Nodulation factors (NFs) are lipochito‐oligosaccharide signal molecules excreted by soil‐living rhizobia. These molecules elicit a range of responses in the legume roots, with which the bacteria can live in symbiosis. In this review we focus on the genetic, pharmacological and cell biological approaches that have been, and are being, undertaken to decipher the signalling pathways that lead to the symbiotic responses in the plant.
Evaluation of spectral imaging for plant cell analysis
Authors: Berg R. H.
Published: April 2004

Fluorescence imaging at high spectral resolution is now a practical reality and has great promise in plant cell biology. Emission spectral curve data can be used computationally to distinguish spectrally similar fluorophores, or to remove autofluorescence, and to spectrally analyse autofluorescent molecules, which are especially abundant in plant tissues. Examples of these applications in plant cells are given, and a comparison is made between the current offerings in spectral imaging laser scanning confocal microscopes.
When Remembering Is Not Enough: Reflecting on Self‐Defining Memories in Late Adolescence
Authors: Thorne Avril , McLean Kate C. , Lawrence Amy M.
Published: April 2004

AbstractThis study examined which kinds of self‐defining memories show spontaneous references to larger meanings, and listener responses to two kinds of meaning—lessons and insights. Narratives of three self‐defining memories and episodes of telling the memories to others were collected from each of 168 late adolescents (Mage=19). Narratives were coded for event type (relationship, mortality, achievement, and leisure) and for references to tension and to meaning (lesson or insight). Narratives of memorable episodes of having told the memories to others were coded for listener response (positive or negative). References to meaning emerged in one‐fourth of the memory narratives, and meaning was more common for self‐defining memory narratives that contained references to tension. Memories that reportedly had not been told to others in the past showed the same proportion of meaning as did memories that had been told to others (23%), with insights more prevalent than lessons. For memories that had been told to others, insights were more likely to be accepted by listeners than lessons. Implications were discussed for understanding the development of meaning in self‐defining memories and the collaborative construction of identity.
Presence of human herpes virus‐8 in saliva and non‐lesional oral mucosa in HIV‐infected and oncologic immunocompromised patients
Authors: Triantos D. , Horefti E. , Paximadi E. , Kyriakopoulou Z. , Karakassiliotis G. , Papanastasiou K. , Lelekis M. , Panos G. , Donta‐Bakoyianni C. , Rapidis A. , Markoulatos P.
Published: April 2004

Background/Aim:  Human Herpes Virus‐8 (HHV‐8) is a recently identified virus etiologically associated with Kaposi's sarcoma. Studies regarding its presence in the oral cavity have given variable results. This study attempted to determine the oral presence of HHV‐8 in an area where classic Kaposi's sarcoma is primarily found such as Greece.

Methods:  Three groups of patients were studied: 10 immunocompromised with hematologic malignancies, 10 immunocompromised with HIV infection and 20 immunocompetent as controls. Whole unstimulated saliva and scrapes from the lingual and the buccal mucosa were collected and polymerase chain reaction was applied to amplify HHV‐8 DNA.

Results:  None of the patients in any group had oral lesions. In the control group, all samples tested negative (0/60). HHV‐8 DNA was detected in 5/30 (17%) of all samples from HIV‐positive patients (the mean value of their CD4+ T‐lymphocytes being 385/mm3) and in 13/30 (43%) of all samples from oncologic patients (mean CD4+ T‐lymphocytes 51/mm3). HHV‐8 DNA was found in 10% of saliva samples and 40% of lingual and buccal scrapes both of HIV‐infected and of oncologic patients.

Conclusion:  HHV‐8 is present in the saliva and the non‐lesional oral mucosa (not simultaneously) of patients with impaired immunity, with or without HIV co‐infection. The oral epithelium seems to represent an independent location of viral residency and may be of viral replication; the clinical implications need further clarification.
Studies on NADH oxidase and alkyl hydroperoxide reductase produced by Porphyromonas gingivalis
Authors: Diaz P. I. , Zilm P. S. , Wasinger V. , Corthals G. L. , Rogers A. H.
Published: April 2004

Enzymes that detoxify oxygen or oxygen radicals are important to anaerobic microorganisms that inhabit oxygenated environments. In previous studies we have determined that Porphyromonas gingivalis W50 cell extracts possess NADH oxidase‐like activity, which increases slightly under oxygenated conditions. The aim of this study was to characterize the protein responsible for this activity in order to establish whether it protects the microorganism from oxidative stress. Protein purification based on NADH oxidase activity did not isolate a conventional NADH oxidase. Instead, the NADH oxidase activity was found to be associated with a FAD‐dependent enzyme identified as 4‐hydroxybutyryl‐CoA dehydratase (AbfD). The biological significance of this activity with respect to protection against oxidative stress is not clear; hydrogen peroxide (H2O2) was present after completion of the NADH oxidase assay with the purified protein. Northern blot analysis, examining the expression of other proteins likely to function as NADH oxidases/peroxidases in P. gingivalis, revealed the transcription of a protein similar to alkyl‐hydroperoxide reductase (AhpF‐C), which could serve as an NADH oxidase and H2O2‐detoxification system. AhpF is transcribed in a polycystronic way with its neighboring gene, which encodes for the coupling protein AhpC. No transcript could be detected for the closest match to an NADH oxidase identified in the P. gingivalis genome sequence. In conclusion, P. gingivalis seems to lack a protective NADH oxidase but AhpF‐C could contribute to its moderate tolerance to reactive oxygen species by metabolizing H2O2.
Treponema denticola immunoinhibitory protein induces irreversible G1 arrest in activated human lymphocytes
Authors: Lee W. , Pankoski L. , Zekavat A. , Shenker B. J.
Published: April 2004

Oral spirochetes may contribute to the pathogenesis of a number of disorders including periodontal and periradicular diseases; however, the mechanism (s) by which these organisms act to cause disease is unknown. We have previously shown that extracts of the oral spirochete, Treponema denticola, contain an immunosuppressive protein (Sip) which impairs human lymphocyte proliferation. The objective of this study was to determine the mechanism by which Sip alters the proliferative response of lymphocytes. Human T‐cells were activated by PHA in the presence or absence of Sip and cell cycle progression was assessed by flow cytometry. Cell cycle distribution was based upon DNA, RNA and protein content as well as expression of the activation markers; CD69 and IL‐2R. Seventy‐two hours following activation with PHA, cells were found in the G0, G1, S and G2/M phases of the cell cycle. In contrast, pretreatment with Sip resulted in a significant reduction of cells in the S and G2/M phases and a concomitant increase in the G1 phase. Sip did not alter the expression of the early activation markers CD69 and CD25R. To determine if G1 arrest resulted in activation of the checkpoint and cell death, we also monitored Sip‐treated cells for apoptosis. Indeed, treatment with Sip resulted in both DNA fragmentation and caspase activation after 96 h. Our results indicate that Sip induces G1 arrest in human T‐cells and, furthermore, that the arrest is irreversible, culminating in activation of the apoptotic cascade. We propose that if cell cycle arrest occurs in vivo, it may result in local and/or systemic immunosuppression and thereby enhance the pathogenicity of spirochetes and/or that of other opportunistic organisms.
The microbial synergy of Peptostreptococcus micros and Prevotella intermedia in a murine abscess model
Authors: Araki H. , Kuriyama T. , Nakagawa K. , Karasawa T.
Published: April 2004

This study characterized the microbial interaction of Peptostreptococcus micros and Prevotella intermedia, the major pathogens of dentoalveolar infection, using a murine model. Subcutaneous injection of P. micros cells in the dorsum of the mouse together with living cells of P. intermedia resulted in a significantly larger abscess when compared with single injection of the organisms (P < 0.02). The abscess size was also significantly increased (P < 0.05) when the plate‐cultured cell suspension of P. micros was injected into mouse with the culture filtrate of P. intermedia. The heat‐treated culture filtrate of P. intermedia also enhanced the virulence of P. micros. P. micros culture filtrate did not affect the virulence of P. intermedia. Interestingly, the virulence of P. micros appeared to be enhanced even when the culture filtrate of P. intermedia was injected at separate sites in the mouse. These results suggest that a heat‐stable product or products of P. intermedia increase the virulence of P. micros indirectly by altering the host condition, whereas living cells of P. micros can directly enhance virulence of P. intermedia.
Expression of somatostatin mRNA and peptides in C‐cell tumours of the thyroid gland in Han Wistar rats
Authors: Pilling Andrew , Jones Stewart , Turton John
Published: April 2004

C‐cell tumours of the thyroid gland are among the most common spontaneous neoplasms of the laboratory rat. With the exception of calcitonin, little attention has been paid to the secretory peptides of C cells during the development of neoplasia. Of these peptides, somatostatin (SS) is of particular interest because it has been shown to have a direct anti‐secretory effect on both thyroid follicular and C cells in vitro. In the present study, in situ hybridization and immunohistochemistry were used to investigate the expression of SS mRNA and SS peptides, in normal C cells and a range of spontaneous proliferative C‐cell lesions in the Han Wistar rat. It was confirmed that a small minority of C cells in the normal rat thyroid gland produce and store SS peptides; however, approximately half of all C‐cell adenomas and C‐cell carcinomas stained positively for SS mRNA and peptides. SS expression was also observed in all metastatic deposits of carcinomas in drainage lymph nodes. From these observations, it appears that C‐cell tumours are more likely to develop from SS‐expressing stem cells, rather than from non‐SS‐expressing stem cells. In addition, a lack of differentiation of neoplastic C cells, or reversion to more primitive cell types, could account for increased number of cells expressing SS in C‐cell tumours relative to the normal C‐cell population. Finally, the mean percentage of cells that stained positively for SS mRNA and peptides appeared to be significantly higher in small C‐cell tumours, suggesting that SS may have exerted a growth‐controlling influence on these lesions.
Evidence of macrophage and lymphocyte, but not dendritic cell, infiltration in posterior uveal melanomas, whilst cultured uveal melanomas demonstrate pluripotency by expressing CD68 and CD163
Authors: Woodward Julia , Sisley Karen , Reeves Graham , Nichols Carmel , Parsons M. Andrew , Mudhar Hardeep , Rennie Ian
Published: April 2004

Although variation in the level of macrophage infiltration has been reported in uveal melanoma, little is known about the expression of other leucocyte markers. An immuno‐ histochemistry study of the levels of expression of macrophage and other leucocyte markers, in a series of 10 primary choroidal melanoma biopsies, was undertaken. Biopsies were either fixed immediately in formalin and embedded in paraffin wax or established as short‐term cultures. Using single‐ and double‐labelling immunohistochemistry, cultured cells and paraffin sections were analysed for a range of melanoma (HMB45, Melan A, S100 and tyrosinase) and immune cell (CD68, CD163, CD45 and CD1a) markers. All samples expressed at least two known melanoma markers. Infiltrating macrophages were present in the majority of sections. When cultured specimens were studied by double‐labelling immunofluorescence, uveal melanoma cells were seen to express macrophage markers or have cross‐reactivity with related proteins. Expression of the leucocyte antigen CD45 was observed in three tumours but was not present in any cultured cells, whilst the expression of the dendritic cell marker CD1a was absent from all samples.
Justice Expectations and Applicant Perceptions
Authors: Bell Bradford S. , Ryan Ann Marie , Wiechmann Darin
Published: April 2004

Expectations, which are beliefs about a future state of affairs, constitute a basic psychological mechanism that underlies virtually all human behavior. Although expectations serve as a central component in many theories of organizational behavior, they have received limited attention in the organizational justice literature. The goal of this paper is to introduce the concept of justice expectations and explore its implications for understanding applicant perceptions. To conceptualize justice expectations, we draw on research on expectations conducted in multiple disciplines. We discuss the three sources of expectations – direct experience, indirect influences, and other beliefs – and use this typology to identify the likely antecedents of justice expectations in selection contexts. We also discuss the impact of expectations on attitudes, cognitions, and behaviors, focusing specifically on outcomes tied to selection environments. Finally, we explore the theoretical implications of incorporating expectations into research on applicant perceptions and discuss the practical significance of justice expectations in selection contexts.
The Applicant Attribution‐Reaction Theory (AART): An Integrative Theory of Applicant Attributional Processing
Authors: Ployhart Robert E. , Harold Crystal M.
Published: April 2004

This article proposes a new theory called the Applicant Attribution‐Reaction Theory (AART) to better understand attributional processes in the formation of applicant reactions. The theory proposes that applicants' affective, behavioral, and cognitive reactions, such as fairness, test perceptions, test performance, and motivation, are fundamentally driven by an attributional process. A key implication of the theory is that perceptions such as fairness and test attitudes carry little explanatory power; instead they are consequences of attributional processing. We provide a brief review of dominant applicant reactions frameworks, review the social psychological literature on attributions, and present the theory. We then contrast the theory to existing conceptualizations, and finally describe its potential for better understanding several key topics in applicant reactions, including the justice judgment process, test performance, and racial subgroup differences. The theory has the potential to integrate many diverse perspectives on applicant reactions, and provides numerous directions for future research and practice.
Improving Participants' Evaluations while Maintaining Validity by a Work Sample‐ Intelligence Test Hybrid
Authors: Klingner Yvonne , Schuler Heinz
Published: April 2004

A type of selection measure is presented which combines the psychometric characteristics of an intelligence test with the surface and content validity characteristics of a work sample for clerical occupations. Consequently, this measure – AZUBI‐BK – is more positively evaluated by participants than a conventional measure of general mental ability (N=1375). Preferences for the work sample‐intelligence test hybrid applied for potential applicants from different school types, for job‐experienced as well as for inexperienced subjects and for members of the ethnic majority as well as for ethnic minorities. AZUBI‐BK showed high correlations with total scores (uncorrected r=.77 and .73) and corresponding factors of two intelligence tests, respectively. Criterion‐related validity was equal to the reference measure in predicting theoretical examinations (uncorrected r=.61) and higher in predicting supervisory ratings (uncorrected r=.43). In the latter case, the new instrument shows incremental validity over an intelligence test but not vice versa; in a regression equation, AZUBI‐BK can fully account for the variance in supervisory assessment. Adverse impact of AZUBI‐BK for ethnic minorities is small which, however, was also true for a conventional intelligence test.
Perceived Fairness in Personnel Selection: Determinants and Outcomes in Different Stages of the Assessment Procedure
Authors: Van Vianen Annelies E. M. , Taris Ruben , Scholten Eveline , Schinkel Sonja
Published: April 2004

This study addresses the determinants and outcomes of fairness perceptions in a real assessment procedure as performed by a selection agency. Fairness perceptions were investigated at three points in time: before the assessment, right after the assessment but before assessment feedback, and after assessment feedback. Using structural equation modeling, we tested how fairness perceptions develop throughout the assessment procedure. Applicants' openness to experiences affected their test beliefs before the actual test‐taking. These beliefs remained powerful in the subsequent stages of the assessment procedure in that they influenced applicants' perceptions of performance, feedback and fairness. In the context of selection by an external selection agency, post‐feedback fairness perceptions were not related to job attractiveness. Perceived feedback treatment and feedback content directly affected job attractiveness.
The Impact of Selection Encounters on Applicants: An Experimental Study into Feedback Effects after a Negative Selection Decision
Authors: Schinkel Sonja , Van Dierendonck Dirk , Anderson Neil
Published: April 2004

This study investigates the role of feedback in minimizing the psychological impact of a negative selection decision on job applicants. The method and findings of a laboratory experiment into subjects' reactions to rejection, combined with feedback on this decision as well as perceptions of procedural and distributive fairness, are discussed. Subjects participating in the experiment (N=119) were asked to complete two GMA tests and were told they had to belong to the 20% best performers to be invited for a selection interview. Upon completion, all subjects received a rejection message, supposedly based on their performance scores on the two tests. Subjects were randomly assigned to one of two feedback conditions: either a mere rejection message, or a rejection message including performance feedback. Analyses revealed that core self‐evaluations and affective well‐being of rejected subjects receiving performance feedback significantly decreased compared to that of subjects in the mere rejection message condition. Furthermore, it was found that procedural fairness perceptions interacted with feedback on subjects' core self‐evaluations, while distributive fairness perceptions interacted with feedback on affective well‐being. These findings raise the question whether performance feedback following a negative selection decision is as advantageous as generally assumed. Implications for giving feedback in rejection situations are discussed in the conclusion.
Effectiveness and pharmaceutical cost of sequential treatment for Helicobacter pylori in patients with non‐ulcer dyspepsia
Authors: De Francesco V. , Della Valle N. , Stoppino V. , Amoruso A. , Muscatiello N. , Panella C. , Ierardi E.
Published: April 2004

Background : A novel 10‐day sequential treatment regimen recently achieved a significantly higher eradication rate than standard 7‐day therapy in both peptic ulcer disease and non‐ulcer dyspepsia. Its higher performance has recently been confirmed using a halved clarithromycin dose in peptic ulcer disease.

Aims : To evaluate whether an acceptable eradication rate could also be obtained by halving the clarithromycin dose in dyspeptic patients and to assess the role of possible factors affecting the outcome of therapy.

Methods : In a prospective, open‐label study, 162 patients with non‐ulcer dyspepsia and Helicobacter pylori infection, assessed by rapid urease test and histology, were enrolled. Patients were randomized to receive either 10‐day sequential therapy, comprising rabeprazole 20 mg b.d. plus amoxicillin 1 g b.d. for the first 5 days, followed by rabeprazole 20 mg b.d., clarithromycin 250 mg b.d. and tinidazole 500 mg b.d. for the remaining 5 days (low‐dose therapy), or a similar schedule with clarithromycin 500 mg b.d. (high‐dose therapy). Four to six weeks after therapy, H. pylori eradication was assessed by endoscopy/histology.

Results : A similar H. pylori eradication rate was observed following low‐ and high‐dose regimens for both per protocol (94% vs. 95%; P = N.S.) and intention‐to‐treat (93% vs. 94%; P = N.S.) analyses. No major side‐effects were reported. Halving the clarithromycin dose leads to a per patient saving in pharmaceutical costs of 24.6 euros. None of the variables examined affected the effectiveness of eradication of the sequential regimen.

Conclusion : A reduction of the clarithromycin dose does not affect H. pylori eradication with the sequential regimen in non‐ulcer dyspepsia and affords lower costs.
Sirolimus‐induced hyperlipidaemia in liver transplant recipients is not dose‐dependent
Authors: Firpi R. J. , Tran T. T. , Flores P. , Nissen N. , Colquhoun S. , Shackleton C. , Martin P. , Vierling J. M. , Poordad F. F.
Published: April 2004

Background : Sirolimus is a potent immunosuppressive medication that acts by inhibiting T‐cell proliferation. It has been used in kidney transplantation because of its lack of nephrotoxicity. It is now being investigated in liver transplantation, but there are concerns about safety and long‐term side effects such as dyslipidaemia. Hypertriglyceridaemia is a common adverse event seen with sirolimus use, and often does not respond to dose reduction or anti‐lipemic drugs.

Method : We report six patients who have developed significant hyperlipidaemia while receiving sirolimus, in spite of therapeutic trough levels.

Conclusion : All six patients showed either resolution or improvement in lipid levels with discontinuation of sirolimus.
DNA vaccine encoding human immunodeficiency virus‐1 Gag, targeted to the major histocompatibility complex II compartment by lysosomal‐associated membrane protein, elicits enhanced long‐term memory response
Authors: De Arruda Luciana Barros , Chikhlikar Priya R. , August J. Thomas , Marques Ernesto T. A.
Published: April 2004

Antigen presentation by major histocompatibility complex type II (MHC II) molecules and activation of CD4+ helper T cells are critical for the generation of immunological memory. We previously described a DNA vaccine encoding human immunodeficiency virus‐1 p55Gag as a chimera with the lysosome‐associated membrane protein (LAMP/gag). The LAMP/gag chimera protein traffics to the MHC II compartment of transfected cells and elicits enhanced immune responses as compared to a DNA vaccine encoding native gag not targeted to the MHC II compartment. We have now investigated the long‐term responses of immunized mice and show that the LAMP/gag DNA vaccine promotes long‐lasting B cell‐ and CD4+ and CD8+ T‐cell memory responses and elicits a potent Gag‐specific CD8+ recall response to challenge with vaccinia virus encoding gag, even 11 months after immunization. In contrast, the immune responses induced by DNA encoding non‐targeted Gag decay rapidly and elicit very low or undetectable levels of Gag‐specific CD4+ and CD8+ memory cells. A single priming immunization with LAMP/gag DNA is sufficient to generate T‐cell memory. Following this initial priming immunization with LAMP/gag DNA, booster immunizations with native gag DNA or the LAMP/gag chimera are equally efficient in eliciting B‐ and T‐cell secondary responses, results in accordance with observations that secondary expansion of CD8+ cells in the boost phase does not require additional CD4+ help. These findings underscore the significance of targeting DNA‐encoded vaccine antigens to the MHC II processing compartments for induction of long‐term immunological memory.
Predicting and explaining plant invasions through analysis of source area floras: some critical considerations
Authors: Pyšek Petr , Richardson David M. , Williamson Mark
Published: April 2004

Comparing species that become invasive with others from the same regional species pool that do not invade raises several issues about the accuracy of analyses attempting to define the determinants of invasiveness. The delimitation of the source area and deciding which species group(s) to include are especially relevant in analyses focusing on species originating in Europe. Historical patterns of immigration of alien species into Europe must be considered since European floras comprise a complex mix of native species, historical introductions (archaeophytes) and relative newcomers (neophytes). We make three main points: (1) Archaeophytes (species introduced to Europe before the discovery of America) differ from natives in a number of traits and in historical association with people; it is misleading to lump archaeophytes with native taxa. (2) Taxa from climatically and geographically different regions, representing distinct floristic geoelements, need to be treated separately, and not as a homogenous pool of potential invaders. Restricting the source species pool to native taxa with comparable phytogeographical characteristics reduces the variation associated with chance of dispersal by humans from the source area. (3) For prediction, a clear distinction should be made between accuracy (the proportion of those found to be alien that were also predicted to be there) and reliability (or predictive value, the proportion of those predicted to become aliens that do so). Information accumulated over centuries by botanists in Central Europe provides an excellent opportunity to deal with these issues and avoid spurious results. To illustrate these issues, we revisit a recently published study of Central‐European plant species as invaders in two Argentinean provinces (Prinzing et al., 2002) to explore and demonstrate the implications of the above points. We hope that future studies will build on these points to achieve more reliable predictions.
Biodiversity patterns of vascular plant species in mountain vegetation in the Faroe Islands
Authors: Fosaa Anna Maria
Published: April 2004

Biodiversity patterns of vascular plant species were studied along altitudinal gradients in the Faroe Islands. Plants were sampled from five different mountains (150–856 m a.s.l.) at 50 m altitudinal intervals. Included in the study were 107 vascular plant species. In order to compare only altitudes with the same number of plots, three different analyses were carried out. One analysis included five mountains from 250 to 750 m a.s.l., one had three mountains from 150 to 750 m a.s.l., and the last one had two mountains from 750 to 850 m a.s.l. The patterns of biodiversity were evaluated on the basis of species richness as the total number of species at each altitudinal interval, as species turnover between altitudes and in relation to the Shannon‐Wiener index. Similar patterns were found for species richness in the three analyses, although richness was higher along the whole transect when five mountains were included. For the Shannon‐Wiener index, only small differences were found among the three analyses. A maximum was seen at 250 m a.s.l. and again at 500 m a.s.l. both in richness and in the Shannon‐Wiener index. Maximum species turnover was found at mid‐altitudes. Total vegetation cover followed the same pattern as richness. In addition to climate, the altitudinal variation of biodiversity may be affected by grazing.
Identification of Critical Stage for Disease Development and Biocontrol of Alternaria Blight of Indian Mustard (Brassica juncea)
Authors: Meena P. D. , Meena R. L. , Chattopadhyay C. , Kumar A.
Published: April 2004

Fungicides mancozeb and carbendazim caused 100% reduction in mycelial growth of Alternaria brassicae over control in vitro while 1% (w/v) aqueous bulb extract of Allium sativum and leaf extract of Acacia nilotica caused significant reductions. In dual culture, GR isolate of Trichoderma viride performed the best among the test isolates of Trichoderma, causing 81%, 82% reduction in mycelial growth of A. brassicae over control. Performance of isolates SI‐2, P and SI‐1 of T. viride were at par (P < 0.01) with that of GR isolate. Spraying of A. brassicae at different ages of the mustard host plant identified 75 days after sowing (d.a.s.) as the most critical age of the mustard plant for development of Alternaria blight severity on the crop with 45 d.a.s. being the next most important one. Mancozeb was the best among all the treatments, resulting in the lowest disease severity on leaves of mustard at both Sewar and Ludhavai as also the lowest A‐value (area under disease progress curve). Performance of bulb extract of A. sativum in checking the disease severity on leaves and pods was at par (P < 0.05) with mancozeb. The GR isolate of T. viride was at par with mancozeb in checking blight severity on mustard leaves at Sewar while performance of the bioagent was significantly (P < 0.05) inferior to the chemical fungicide at Ludhavai. Performance of the bioagent isolate GR of T. viride in checking the disease severity on pods was at par (P < 0.05) with mancozeb at both Sewar and Ludhavai, the treatment recording the lowest A‐value on pods. While application of bulb extract of A. sativum resulted in highest seed yield at Sewar in 2001–2002, the bioagent isolate GR of T. viride did so at Ludhavai, both the treatments being at par (P < 0.05) with mancozeb and significantly higher than control. Application of bulb extract of A. sativum at 45 and 75 d.a.s. resulted in lowest blight severity on leaves and pods as also in highest seed yield among the different single and combination of treatments. Although disease severity in the treatment was at par (P < 0.05) with that in mancozeb, application of the plant extract at the two stages of crop growth resulted in significantly higher seed yield compared with the two applications of the chemical fungicide. However, application of the treatments singly only at 75 d.a.s., GR isolate of T. viride at 45 and 75 d.a.s., A. sativum 45 d.a.s. + T. viride 75 d.a.s., and T. viride 45 d.a.s. + A. sativum 75 d.a.s. resulted in seed yield at par (P < 0.05) with application of bulb extract of A. sativum at 45 and 75 d.a.s.
Detection and Identification of Aster Yellows (16SrI) Phytoplasma in Peach Trees in Jordan by RFLP Analysis of PCR‐Amplified Products (16S rDNAs)
Authors: Anfoka G. H. , Fattash I.
Published: April 2004

Aster yellows phytoplasma were detected, for the first time, in peach trees in Al‐Jubiha and Homret Al‐Sahen area. Leaves of infected trees showed yellow or reddish, irregular water‐soaked blotches. Discoloured areas become dry and brittle and the dead tissues dropped out. Under severe infections, leaves fall down and fruits dropped prematurely. Phytoplasmas were detected from all symptomatic peach trees by polymerase chain reaction (PCR) using universal phytoplasmas primers P1/P7 followed by R16F2/R2. No amplification products were obtained from templates of asymptomatic peaches. PCR products (1.2 kb) used for restriction fragment length polymorphism analysis (RFLP) after digestion with endonuclease AluI, HpaII, KpnI and RsaI produced the same restriction profiles for all samples, and they were identical with those of American aster yellows (16SrI) phytoplasma strain. This paper is the first report on aster yellows phytoplasma affecting peach trees in Jordan.
Field Studies of Cross Protection with Cassava Mosaic Geminiviruses in Uganda
Authors: Owor B. , Legg J. P. , Okao‐Okuja G. , Obonyo R. , Kyamanywa S. , Ogenga‐Latigo M. W.
Published: April 2004

The effect of cassava mosaic virus disease (CMD) was compared on plants grown from cuttings that were initially virus‐free at planting and those infected with a mild strain of East African cassava mosaic virus‐Uganda (EACMV‐UG). All initially healthy plants developed CMD symptoms within 5 months of planting (MAP) at both trial sites in Uganda, although spread was more rapid at Kamuli than at Serere. Significantly (P < 0.001) higher symptom severity scores were recorded in initially healthy plants, which had average scores of 3.6 and 3.5 at Kamuli and Serere, respectively, compared with 2.8 for mildly diseased plants at each location. Severity scores of 4 and 5 were more frequent in initially healthy plants, accounting for 77 and 39% of the total infections recorded in comparison with 47 and 11% in mildly diseased plants at Kamuli and Serere, respectively. Mildly diseased plants were significantly taller than initially healthy plants 8 and 12 MAP at both locations. However, the converse was true 4 MAP although differences were significant at Serere but not at Kamuli. Mildly diseased plants yielded significantly more tuberous roots than initially healthy plants at Kamuli but not at Serere. Average total weights of tuberous roots per plant were 2.48 and 1.63 kg for mildly diseased and initially healthy plants at Kamuli and 4.46 and 4.61 kg at Serere, respectively. These results may help to explain the increased prevalence in recent years of mildly diseased plants of local CMD‐susceptible cultivars in eastern Uganda, from where these varieties virtually disappeared following the severe CMD epidemic in the 1990s. The results also provide the first field evidence of a cross protective effect of mild strains of a cassava mosaic geminivirus.
Tort, Insurance and Incoherence
Authors: Morgan Jonathan
Published: April 2004

Some commentators have doubted whether, as is generally believed, liability insurance has had a significant expansionary effect on the law of tort. This article contends that the common assumption is, indeed, correct, and the crucial influence of insurance is clearly seen in the recent cases of Vowles v Evans and Gwilliam v West Herts NHS Trust. Once this has been acknowledged, the consequent radical incoherence in the basis of tort law needs to be confronted. The argument here is that only through faithful adherence to principles of individual responsibility and corrective justice, inherent as these are within the structure of tort law, can we hope to preserve coherence in the law of tort.
The Continuing Conceptual Crisis in the Common Law of the Contract of Employment
Authors: Barmes Lizzie
Published: April 2004

The effects on the common law of the contract of employment of the decision of the House of Lords in Johnson v Unisys Ltd are considered. The focus is on liability rather than remedies. It is argued that the case created conceptual instability in the common law understanding of a breach of a contract of employment. The logical consequence of the majority reasoning is that in some cases the existence or not of a breach by an employer is contingent on an employee's reaction. Relevant case law history and developments since the Johnson decision inform a detailed critique of the arguments that underpinned it. A solution is suggested according to which, prima facie, contracts of employment would be required to be performed in accordance with terms that have been implied by law.
High incidence of defective high‐shear platelet function among platelet donors
Authors: Harrison Paul , Segal Helen , Furtado Charlene , Verjee Salim , Sukhu Kampta , Murphy Michael F.
Published: April 2004

BACKGROUND: Because single‐donor plateletpheresis concentrates now account for a large percentage of PLT concentrates, the PLT quality of individual donations is increasingly important. There has been little previous work on PLT function in blood donors.

STUDY DESIGN AND METHODS: The aim of this study was to investigate the prevalence of defective PLT function among 100 healthy UK PLT donors on 3 consecutive donation days. Citrated blood samples were taken before plateletpheresis. High‐shear PLT function testing was performed by a PLT function analyzer (PFA‐100, Dade Behring), within both collagen‐ADP (CADP) and collagen‐epinephrine (CEPI) cartridges.

RESULTS: Sixteen percent of PLT donors (mainly over the 3 donating days) had prolonged CEPI closure times (CTs) only, indicative of an aspirin‐like pattern; 9 percent had a severe defect with prolonged CEPI CTs between 200 and 300 seconds, and 4 percent had maximal CEPI CTs of greater than 300 seconds. The majority of prolonged CEPI CTs appeared transient in nature.

CONCLUSION: PLT dysfunction as detected by the PFA‐100 is surprisingly common within a voluntary PLT donor population. The majority of CEPI defects appeared transient in nature and are indicative of surreptitious intake of cyclooxygenase inhibitors (e.g., aspirin). Identification of defective PLT function within donors would provide a simple means to eradicate defective PLTs from being clinically utilized.
Supernatant from stored red blood cell primes inflammatory cells: influence of prestorage white cell reduction
Authors: Sparrow R.L. , Patton K.A.
Published: April 2004

BACKGROUND: The contribution of RBC transfusion to adverse patient outcomes is controversial. There is conflicting clinical data and limited biologic data that provide an underpinning biologic rationale for any adverse impacts from RBC transfusion. This study used in‐vitro measures of PMN stimulation to determine the ability of supernatant from RBCs to stimulate allogeneic WBCs and to determine the influence of residual donor WBCs and storage time on the proinflammatory potential of RBCs.

STUDY DESIGN AND METHODS: Three types of RBCs were assessed: standard non‐WBC‐reduced RBCs (S‐RBCs), buffy coat‐poor RBCs (BCP‐RBCs), and prestorage WBC‐filtered RBC (LF‐RBCs). Supernatant was collected weekly up to Day 42 of storage. PMN priming by supernatant from RBCs was determined by three methods: induction of CD11b expression on PMNs, induction of IL‐8 release from PMNs, and the chemotactic effect of supernatant on PMNs.

RESULTS: Supernatant from S‐RBCs induced the expression of CD11b on PMNs, primed PMNs to release IL‐8, and was chemotactic for PMNs. The magnitude of this PMN‐priming progressively amplified with storage time. In contrast, supernatant from BCP‐RBCs or LF‐RBCs did not significantly prime PMNs. The PMN‐priming effect of supernatant from RBCs correlated more closely with the level of MNCs in the RBCs than PMN content.

CONCLUSION: Supernatant from stored S‐RBCs prime unstimulated allogeneic PMNs in vitro. Prestorage buffy‐coat WBC reduction was as effective as WBC depletion in abrogating this proinflammatory response elicited by supernatants from RBCs. The clinical consequences, if any, of these findings for transfusion recipients are unknown.
Evolution of theOalleles of the human ABO blood group gene
Authors: Roubinet Francis , Despiau Stéphanie , Calafell Francesc , Jin Fen , Bertanpetit Jaume , Saitou Naruya , Blancher Antoine
Published: April 2004

BACKGROUND:To date, at least 40 different allelesOhave been characterized on the basis of exon 6 and exon 7 sequences but not always for intron 6.

STUDY DESIGN AND METHODS:Among 415 individuals, from four continents (Africa, Europe, South America, and Asia), studied for exon 6 and exon 7 sequences, we selected 46 individuals (of respective phenotypes O [39], AB [3], B [3], or A [1]) for sequencing 1800‐bp amplicons spanning exon 6, intron 6, and exon 7. The amplicons were characterized either by direct sequencing or after cloning when required.

RESULTS:We defined 14 new intron 6Oallele sequences,including four recombinant alleles. Based on sequence comparison, a phylogenetic network was constructed. It confirmed recombinant allele origins and that mostOalleles are derived by point mutations from the two worldwide distributed allelesO01andO02.

CONCLUSION:AlleleOphylogenetic analysis suggests that the most frequent silencing mutation (deletion of a G in exon 6) appeared once in human evolution in the ancientO02allele lineage and that alleleO01resulted from an interallele exchange betweenO02andA101. Assuming constancy of evolutionary rate, diversification of the representative alleles of the three humanABOlineages (A101,B101,andO02) was estimated at 4.5 to 6 million years ago.
The donor notification process from the donor's perspective
Authors: Kleinman Steven , Wang Baoguang , Wu Ying , Glynn Simone A. , Williams Alan , Nass Catharie , Ownby Helen , Busch Michael P. ,   Retrovirus Epidemiology Donor Study
Published: April 2004

BACKGROUND: Despite large numbers of blood donors being notified of abnormal infectious disease screening results, there has been little scientific study of the effects of this process.

STUDY DESIGN AND METHODS: With a 28‐item questionnaire, an anonymous mail survey was conducted of 4141 blood donors notified of 15 distinct categories of abnormal infectious disease screening and confirmatory test results.

RESULTS: The survey had a 42 percent response rate, and 10 percent of the respondents did not recall being notified of their results. Of the 1556 respondents who recalled being notified, 27 percent contacted the blood center for further information, 60 percent discussed their results with a health care provider, and 73 percent of permanently or indefinitely deferred donors correctly understood their deferral status. Confusion and emotional upset were reported in 81 and 75 percent of notified donors, respectively.

CONCLUSIONS: The notification process appears to achieve most of its aims in the majority of donors. Nevertheless, some donors did not understand that they were ineligible for future donation, and many donors were confused and upset. These data indicate that the adverse impact of notifying donors about abnormal test results needs to be considered when new blood donor screening tests and confirmatory algorithms are being licensed and implemented. Further studies of the effectiveness of newer revised donor notification materials are needed.
Evaluation of the sensitivity of red blood cell markers to detect photodynamic membrane damage
Authors: Wagner Stephen J. , Skripchenko Andrey , Thompson‐Montgomery Dedeene , Awatefe Helen
Published: April 2004

BACKGROUND: Photodynamic dyes have been used to investigate pathogen reduction methods in RBC suspen‐sions, but treatment with sensitizers and light can produce unwanted membrane damage during routine blood bank storage. This study compares the relative sensitivity of three assays for detecting RBC membrane damage.

STUDY DESIGN AND METHODS: RBCs were treated with dimethylmethylene blue and red light‐emitting diode light under four conditions differing in photodynamic stringency and subsequently stored under refrigerated conditions for up to 42 days. Hemolysis, potassium release, and the apoptosis marker annexin V binding were assayed immediately after phototreatment and following storage.

RESULTS: In terms of increasing sensitivity for detecting photodynamic RBC membrane damage was enhanced ion leakage >> hemolysis > annexin V binding.

CONCLUSION: Although very stringent photodynamic treatment conditions generate annexin V‐positive RBCs, the assay will not detect more subtle membrane damage that is readily detected by other well‐established methods. In addition, many RBCs destined for photo‐induced hemolysis later in storage are annexin V‐negative throughout the storage period, suggesting that the two measures are not directly related.
Performance of time‐series methods in forecasting the demand for red blood cell transfusion
Authors: Pereira Arturo
Published: April 2004

BACKGROUND: Planning the future blood collection efforts must be based on adequate forecasts of transfusion demand. In this study, univariate time‐series methods were investigated for their performance in forecasting the monthly demand for RBCs at one tertiary‐care, university hospital.

STUDY DESIGN AND METHODS: Three time‐series methods were investigated: autoregressive integrated moving average (ARIMA), the Holt‐Winters family of exponential smoothing models, and one neural‐network‐based method. The time series consisted of the monthly demand for RBCs from January 1988 to December 2002 and was divided into two segments: the older one was used to fit or train the models, and the younger to test for the accuracy of predictions. Performance was compared across forecasting methods by calculating goodness‐of‐fit statistics, the percentage of months in which forecast‐based supply would have met the RBC demand (coverage rate), and the outdate rate.

RESULTS: The RBC transfusion series was best fitted by a seasonal ARIMA(0,1,1)(0,1,1)12 model. Over 1‐year time horizons, forecasts generated by ARIMA or exponential smoothing laid within the ± 10 percent interval of the real RBC demand in 79 percent of months (62% in the case of neural networks). The coverage rate for the three methods was 89, 91, and 86 percent, respectively. Over 2‐year time horizons, exponential smoothing largely outperformed the other methods. Predictions by exponential smoothing laid within the ± 10 percent interval of real values in 75 percent of the 24 forecasted months, and the coverage rate was 87 percent.

CONCLUSION: Over 1‐year time horizons, predictions of RBC demand generated by ARIMA or exponential smoothing are accurate enough to be of help in the planning of blood collection efforts. For longer time horizons, exponential smoothing outperforms the other forecasting methods.
Recommendations for optimized settings of the Amicus Crescendo cell separator for the collection of CD34+ progenitor cells
Authors: Hartwig Dirk , Dorn Isabel , Kirchner Holger , Schlenke Peter
Published: April 2004

BACKGROUND: CD34+ PBPCs for autologous transplantation purposes are collected by leukapheresis procedures on automated cell separators. In this study, the influence of different parameters on collection efficiency (CE) of the Amicus Crescendo cell separator (Baxter) was investigated.

STUDY DESIGN AND METHODS: A total of 146 PBPC collections with Amicus cell separators were performed in 56 patients with either settings recommended by the manufacturer or modified settings to identify variables that have a significant and important impact on CE.

RESULTS: By use of a standard setting with a cycle volume of 1400 mL, CE significantly decreases when patients’ preapheresis peripheral blood WBC counts are between 25,000 and 35,000 per µL. CE can be improved if cycle volume is reduced to 1000 mL. If WBC concentrations exceed 55,000 per µL before apheresis, CE also significantly decreases despite of reduced cycle volume. Additionally, high flow rates greater than 60 mL per minute significantly reduce CE.

CONCLUSION: Parameters influencing the outcome of CD34+ PBPC collections were identified, such as patients’ WBC count, cycle volume, and whole blood flow rate. An optimized adjustment of these variables will further increase the CE of the device.
Virtual crack closure technique: History, approach, and applications
Authors: Krueger Ronald
Published: April 2004

An overview of the virtual crack closure technique is presented. The approach used is discussed, the history summarized, and insight into its applications provided. Equations for two-dimensional quadrilateral finite elements with linear and quadratic shape functions are given. Formulas for applying the technique in conjunction with three-dimensional solid elements as well as plate/shell elements are also provided. Necessary modifications for the use of the method with geometrically nonlinear finite element analysis and corrections required for elements at the crack tip with different lengths and widths are discussed. The problems associated with cracks or delaminations propagating between different materials are mentioned briefly, as well as a strategy to minimize these problems. Due to an increased interest in using a fracture mechanics–based approach to assess the damage tolerance of composite structures in the design phase and during certification, the engineering problems selected as examples and given as references focus on the application of the technique to components made of composite materials.