bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk factors for coronary heart disease in women with systemic lupus erythematosus: The Toronto Risk Factor Study
Authors: Bruce Ian N. , Urowitz Murray B. , Gladman Dafna D. , Ibañez Dominique , Steiner George
Published: November 2003

Objective

Because women with systemic lupus erythematosus (SLE) are 5–8 times more likely to develop coronary heart disease (CHD) than are women in the general population, we assessed the prevalence of classic risk factors for CHD in women with SLE.

Methods

Consecutive female patients with SLE who were without evidence of CHD and were attending a large lupus clinic in Toronto were studied. The control population was recruited from among age‐matched subjects attending a family practice unit for an annual physical examination. The prevalence of classic CHD risk factors and the 10‐year risk of a CHD‐related event were determined using the Framingham risk assessment formula. Lipid subfractions, other metabolic risk factors, lifestyle variables, and demographic characteristics were also compared between the 2 groups.

Results

We studied 250 SLE patients and 250 controls whose mean ± SD age was 44.8 ± 12 years and 44.3 ± 15 years, respectively. Hypertension and diabetes were significantly more common among the SLE patients. Although the SLE patients had a higher mean number of CHD risk factors per patient, the 10‐year risk of a CHD‐related event, using the Framingham multiple risk factor assessment, was the same in SLE patients and controls (3.2%). Compared with controls, SLE patients had higher levels of very low‐density lipoprotein cholesterol and total triglycerides, and had higher levels of homocysteine despite having higher folate levels. Premature menopause, sedentary lifestyle, and an at‐risk body habitus were also more prevalent in SLE patients.

Conclusion

Women with SLE have a range of detectable coronary risk factors that are not fully reflected in the Framingham risk factor formula. These factors are likely to contribute to the loss of protection from CHD that has been observed in SLE.
Articular, monoclonal γ3 heavy‐chain deposition disease: Characterization of a partially deleted heavy‐chain gene and its protein product synthesized in vivo and in vitro
Authors: Thompson Keith M. , Sletten Knut , Brandtzaeg Per , Källberg Eva , Wien Tale Norbye , Husby Gunnar
Published: November 2003

Objective

A patient presented with heavy‐chain deposition disease (HCDD), exhibiting severe erosive polyarthropathy caused by synovial deposits of abnormal monoclonal, heavily deleted free γ3 heavy chains lacking the VH and CH1 domains. The absence of VH was surprising, since it is considered important for pathogenic tissue deposition. This study was undertaken to analyze the genetic structure of the heavy chain, the protein product synthesized in vitro, and that deposited in the synovium in comparison with the serum and urinary proteins.

Methods

Hybridomas were made by fusion of blood and bone marrow mononuclear cells with mouse myeloma cells. Cloned B cell hybridomas secreting γ3 were selected and analyzed by polymerase chain reaction. Purified hybridoma Ig was sequenced by Edman degradation. Antiserum raised to a peptide corresponding to residues 2–15 of the truncated VH was used in Western blots of synovial tissue.

Results

The hybridomas secreted free γ3 chains consisting of a VH4 gene truncated 21 nucleotides into the first complementarity‐determining region and then reading straight into the hinge region. The amino acid sequence confirmed the presence of residues 1–32 of the VH4 gene. Immunoblotting of synovial tissue showed the presence of Ig with truncated VH.

Conclusion

The γ3 heavy chain had a deletion of VH from codon 33 and of the entire CH1. In vivo, the 32 VH amino acids were proteolytically degraded. In the joint, however, the 32 residues of VH remained intact, consistent with a pathogenic role of VH for tissue deposition. To our knowledge, this is the first reported case of γHCDD causing an erosive, polyarticular arthropathy as the dominating clinical feature.
Generation and characterization of LymphoStat‐B, a human monoclonal antibody that antagonizes the bioactivities of B lymphocyte stimulator
Authors: Baker Kevin P. , Edwards Bryan M. , Main Sarah H. , Choi Gil H. , Wager Ruth E. , Halpern Wendy G. , Lappin Patrick B. , Riccobene Todd , Abramian Donara , Sekut Les , Sturm Bonnie , Poortman Carol , Minter Ralph R. , Dobson Claire L. , Williams Elizabeth , Carmen Sara , Smith Rodger , Roschke Viktor , Hilbert David M. , Vaughan Tristan J. , Albert Vivian R.
Published: November 2003

Objective

To identify and characterize a fully human antibody directed against B lymphocyte stimulator (BLyS), a tumor necrosis factor–related cytokine that plays a critical role in the regulation of B cell maturation and development. Elevated levels of BLyS have been implicated in the pathogenesis of autoimmune diseases.

Methods

A human phage display library was screened for antibodies against human BLyS. A human monoclonal antibody, LymphoStat‐B, specific for human BLyS was obtained from the library screening and subsequent affinity optimization mutagenesis. The antibody was tested for inhibition of human BLyS in vitro and in an in vivo murine model. Additionally, the consequences of BLyS inhibition were tested in vivo by administration of LymphoStat‐B to cynomolgus monkeys.

Results

LymphoStat‐B bound with high affinity to human BLyS and inhibited the binding of BLyS to its 3 receptors, TACI, BCMA, and BLyS receptor 3/BAFF‐R. LymphoStat‐B potently inhibited BLyS‐induced proliferation of B cells in vitro, and administration of LymphoStat‐B to mice prevented human BLyS‐induced increases in splenic B cell numbers and IgA titers. In cynomolgus monkeys, administration of LymphoStat‐B resulted in decreased B cell representation in both spleen and mesenteric lymph nodes.

Conclusion

A fully human monoclonal antibody has been isolated that binds to BLyS with high affinity and neutralizes human BLyS bioactivity in vitro and in vivo. Administration of this antibody to cynomolgus monkeys resulted in B cell depletion in spleen and lymph node. This antibody may prove therapeutically useful in the treatment of autoimmune diseases in humans.
The −174G allele of the interleukin‐6 gene confers susceptibility to systemic arthritis in children: A multicenter study using simplex and multiplex juvenile idiopathic arthritis families
Authors: Ogilvie Emma M. , Fife Mark S. , Thompson Susan D. , Twine Natalie , Tsoras Monica , Moroldo Marta , Fisher Sheila A. , Lewis Cathryn M. , Prieur Anne‐Marie , Glass David N. , Woo Patricia
Published: November 2003

Objective

Levels of interleukin‐6 (IL‐6) have been shown to correlate with the fever and disease activity of systemic juvenile idiopathic arthritis (JIA). In a previous case–control study, a significant association between the IL‐6 −174 nucleotide variant and systemic JIA was noted, and HeLa cell transfection assays show functional differences in levels of transcription of the IL‐6 −174 alleles. The present study was undertaken to confirm the previous findings and to assess possible association with variations of the AnTn tract in the promoter.

Methods

We studied a cohort of JIA families from 3 countries, using transmission disequilibrium testing. Genotyping of the −174 nucleotide variant was done by restriction fragment length polymorphism, heteroduplex analysis, or allelic discrimination. The AnTn tract at −392 to −373 was typed using DNA sequencing. Statistical analysis was performed using the programs Transmit and EHplus.

Results

There was a significant excess transmission of the −174G allele in the systemic JIA families (P = 0.041). The excess transmission was only to systemic JIA patients with age at onset >5 years (P = 0.007). No significant association with the other subtypes was found. No AnTn alleles or −174/AnTn haplotypes were significantly associated with systemic JIA.

Conclusion

This study confirms that the IL‐6 –174 nucleotide variant is significantly associated with systemic JIA. The significant excess transmission to patients with age at onset >5 years but not to those with age at onset ≤5 years suggests that there may be genetic heterogeneity between the 2 groups.
Evidence for a key role of leptin in osteoarthritis
Authors: Dumond Hélène , Presle Nathalie , Terlain Bernard , Mainard Didier , Loeuille Damien , Netter Patrick , Pottie Pascale
Published: November 2003

Objective

To evaluate the contribution of leptin (an adipose tissue–derived hormone) to the pathophysiology of osteoarthritis (OA), by determining the level of leptin in both synovial fluid (SF) and cartilage specimens obtained from human joints. We also investigated the effect of leptin on cartilage, using intraarticular injections of leptin in rats.

Methods

Leptin levels in SF samples obtained from OA patients undergoing either knee replacement surgery or knee arthroscopy were measured by enzyme‐linked immunosorbent assay. In addition, histologic sections of articular cartilage and osteophytes obtained during surgery for total knee replacement were graded using the Mankin score, and were immunostained using antibodies to leptin, transforming growth factor β (TGFβ), and insulin‐like growth factor 1 (IGF‐1). For experimental studies, various doses of leptin (10, 30, 100, and 300 μg) were injected into the knee joints of rats. Tibial plateaus were collected and processed for proteoglycan synthesis by radiolabeled sulfate incorporation, and for expression of leptin, its receptor (Ob‐Rb), and growth factors by reverse transcriptase–polymerase chain reaction and immunohistochemical analysis.

Results

Leptin was observed in SF obtained from human OA–affected joints, and leptin concentrations correlated with the body mass index. Marked expression of the protein was observed in OA cartilage and in osteophytes, while in normal cartilage, few chondrocytes produced leptin. Furthermore, the pattern and level of leptin expression were related to the grade of cartilage destruction and paralleled those of growth factors (IGF‐1 and TGFβ1). Animal studies showed that leptin strongly stimulated anabolic functions of chondrocytes and induced the synthesis of IGF‐1 and TGFβ1 in cartilage at both the messenger RNA and the protein levels.

Conclusion

These findings suggest a new peripheral function of leptin as a key regulator of chondrocyte metabolism, and indicate that leptin may play an important role in the pathophysiology of OA.
Cyclic tensile stretch loaded on bovine chondrocytes causes depolymerization of hyaluronan: Involvement of reactive oxygen species
Authors: Yamazaki K. , Fukuda K. , Matsukawa M. , Hara F. , Matsushita T. , Yamamoto N. , Yoshida K. , Munakata H. , Hamanishi C.
Published: November 2003

Objective

We have previously demonstrated that reactive oxygen species (ROS) are involved in cartilage degradation. Decreased size of hyaluronan (HA), the major macromolecule in synovial fluid, to which it imparts viscosity, is reported in patients with arthritis. The purpose of this study was to determine the alteration in the molecular weight range of HA as a result of mechanical deformation loaded on the chondrocytes, as well as the involvement of ROS in this action.

Methods

ROS were generated via the oxidation of hypoxanthine by xanthine oxidase. Cyclic tensile stretch was loaded using a vacuum‐operated instrument. Levels of HA were measured using a sandwich enzyme‐binding assay. Superoxide dismutase (SOD) activity and ROS were measured using water‐soluble tetrazolium and a chemiluminescent probe, respectively.

Results

ROS depolymerized HA molecules. Cyclic tensile stretch depolymerized HA and induced ROS. SOD inhibited not only ROS induction but also HA depolymerization caused by the mechanical stress.

Conclusion

ROS play an important role in mechanical stress–induced HA depolymerization.
Coffee consumption and risk of rheumatoid arthritis
Authors: Karlson Elizabeth W. , Mandl Lisa A. , Aweh Gideon N. , Grodstein Francine
Published: November 2003

Objective

Recent reports have suggested an association between consumption of coffee or decaffeinated coffee and the risk of rheumatoid arthritis (RA), although data are sparse and somewhat inconsistent. Furthermore, existing studies measured dietary exposures and potential confounders only at baseline and did not consider possible changes in diet or lifestyle over the followup period. We studied whether coffee, decaffeinated coffee, total coffee, tea, or overall caffeine consumption was associated with the risk of RA, using the Nurses' Health Study, a longitudinal cohort study of 121,701 women.

Methods

Information on beverage consumption was assessed with a food frequency questionnaire (FFQ) that was completed every 4 years, from baseline in 1980 through 1998. Among the 83,124 women who completed the FFQ at baseline, the diagnosis of incident RA (between 1980 and 2000) was confirmed in 480 women by a connective tissue disease screening questionnaire and medical record review for American College of Rheumatology criteria. Relationships between intake of various beverages and the risk of RA were assessed in age‐adjusted models and in multivariate Cox proportional hazards models including the cumulative average intake of each beverage during the followup period, adjusted for numerous potential confounders. In addition, for direct comparisons with prior reports, multivariate analyses were repeated using only baseline beverage information.

Results

We did not find a significant association between decaffeinated coffee consumption of ≥4 cups/day (compared with no decaffeinated coffee consumption) and subsequent risk of incident RA, in either an adjusted multivariate model (relative risk [RR] 1.1, 95% confidence interval [95% CI] 0.5–2.2) or a multivariate model using only baseline reports of decaffeinated coffee consumption (RR 1.0, 95% CI 0.6–1.7). Similarly, there was no relationship between cumulative caffeinated coffee consumption and RA risk (RR 1.1, 95% CI 0.8–1.6 for ≥4 cups per day versus none) or between tea consumption and RA risk (RR 1.1, 95% CI 0.7–1.8 for >3 cups/day versus none). Total coffee and total caffeine consumption were also not associated with the risk of RA.

Conclusion

In this large, prospective study, we find little evidence of an association between coffee, decaffeinated coffee, or tea consumption and the risk of RA among women.
Cellular basis of ectopic germinal center formation and autoantibody production in the target organ of patients with Sjögren's syndrome
Authors: Salomonsson Stina , Jonsson Malin V. , Skarstein Kathrine , Brokstad Karl A. , Hjelmström Peter , Wahren‐Herlenius Marie , Jonsson Roland
Published: November 2003

Objective

To investigate functional properties of the germinal center (GC)–like structures observed in salivary glands of patients with Sjögren's syndrome (SS) and to determine the frequency with which such structures develop.

Methods

Hematoxylin and eosin–stained sections from 165 minor salivary gland biopsy samples were screened for GC‐like structures. Expression of markers for GCs (CD3, CD20, Ki‐67, CD35, CD31), adhesion molecules (intercellular adhesion molecule 1, lymphocyte function–associated antigen 1, vascular cell adhesion molecule 1, very late activation antigen 4), chemokines (CXCL13, CCL21, CXCL12), and production of autoantibodies (anti‐Ro/SSA and anti‐La/SSB) was investigated by immunohistochemistry. Apoptosis was investigated by TUNEL staining.

Results

GC‐like structures were observed in 28 of 165 patients (17%). When GCs were defined as T and B cell aggregates with proliferating cells with a network of follicular dendritic cells and activated endothelial cells, such microenvironments were found in all patients in whom structures with GC‐like morphology were observed. The defined microenvironments were not found in patients without apparent GC‐like structures. The GCs formed within the target tissue showed functional features with production of autoantibodies (anti‐Ro/SSA and anti‐La/SSB) and apoptotic events (by TUNEL staining), and the local production of anti‐Ro/SSA and anti‐La/SSB autoantibodies was significantly increased (P = 0.04) in patients with GC development.

Conclusion

Lymphoid neogenesis and functional ectopic GC formation take place in salivary glands of a subset of patients with SS. Our data suggest that the ectopic secondary lymphoid follicles contain all elements needed for driving the autoimmune response. Our findings underscore a key role for the target organ in recruitment of inflammatory cells and propagation of the disease process.
A novel polymorphism in the Fcγ receptor IIB (CD32B) transmembrane region alters receptor signaling
Authors: Li Xiaoli , Wu Jianming , Carter Robert H. , Edberg Jeffrey C. , Su Kaihong , Cooper Glinda S. , Kimberly Robert P.
Published: November 2003

Objective

The low‐affinity receptor Fcγ receptor IIb (FcγRIIb), with an immunoreceptor tyrosine‐based inhibitory motif (ITIM) in the cytoplasmic domain, down‐regulates humoral immune responses and modulates the risk of autoimmunity in animal models. The transmembrane domain of FcγRIIb may also contribute to receptor signaling. Therefore, we investigated the biologic significance of single‐nucleotide polymorphisms (SNPs) throughout the coding region.

Methods

Discovery of SNPs in FCGR2B was performed by direct cycle sequencing of complementary DNA samples derived by reverse transcriptase–polymerase chain reaction. To assess the biologic significance of the nonsynonymous transmembrane SNP, we studied 3 functions influenced by the FcγRIIb transmembrane domain: tyrosine dephosphorylation of CD19, inhibition of B cell receptor (BCR)–induced calcium response, and modulation of BCR‐ or anti‐Fas–induced apoptosis.

Results

The nonsynonymous C‐to‐T transition in the first cytoplasmic exon, originally reported in the Raji cell line, was not found in either the African‐American or the Caucasian population, but a nonsynonymous T‐to‐C transition at nucleotide 775 in exon 4 of FCGR2B, which changes isoleucine to threonine at residue 187 in the transmembrane domain, was significantly more common in African Americans. Using the FcγRIIb‐negative mouse B cell line IIA1.6, we expressed both allelic forms as both full‐length and truncated cytoplasmic domain constructs. The FCGR2B‐187T allele mediated a higher level of CD19 dephosphorylation (P = 0.029) and a greater degree of inhibition of the calcium response (P = 0.003) when co‐engaged with BCR than did FCGR2B‐187I, independent of the presence of the ITIM. In contrast, FcγRIIb modulation of BCR‐induced and anti‐Fas antibody–induced cell death rates were similar in IIA1.6 cells expressing either the 187I or the 187T allelic form.

Conclusion

The differential activity of FCGR2B alleles suggests a novel mechanism of FcγRIIb regulation that may influence the risk of autoimmune disease.
Inflammation and bone resorption as independent factors of accelerated arterial wall thickening in patients with rheumatoid arthritis
Authors: Nagata‐Sakurai Mayumi , Inaba Masaaki , Goto Hitoshi , Kumeda Yasuro , Furumitsu Yutaka , Inui Kentaro , Koyama Hidenori , Emoto Masanori , Ishimura Eiji , Shoji Tetsuo , Nishizawa Yoshiki
Published: November 2003

Objective

We recently reported that rheumatoid arthritis (RA) patients had increased intima‐media thickness (IMT) of the common carotid artery (CCA). The present longitudinal study was performed to determine whether the change in arterial thickness was accelerated in RA patients and to determine which factor was important in the progression of arterial wall changes.

Methods

We studied 62 female RA patients with stable disease activity and 63 healthy female controls. IMT of the CCA was measured twice by high‐resolution B‐mode ultrasonography. The second examination was performed 18–36 months after the first, and changes were expressed as millimeters of increase per year. Baseline examinations included blood markers of inflammation and urinary calcium excretion (expressed as the calcium‐to‐creatinine ratio).

Results

RA patients showed a significantly greater increase in IMT of the CCA compared with controls. In univariate analyses of the RA patient data, the C‐reactive protein (CRP) level correlated with the increase in CCA IMT. Other markers of inflammation (the erythrocyte sedimentation rate and white blood cell and platelet counts) also showed significant positive associations with the annual increase in CCA IMT in multiple regression models when adjusted for age, smoking status, blood pressure, and serum cholesterol level. The urinary calcium‐to‐creatinine ratio was also significantly associated with an increase in CCA IMT. Moreover, both the CRP level and the urinary calcium‐to‐creatinine ratio were significantly and independently associated with the increase in IMT of the CCA.

Conclusion

Patients with RA have a higher rate of increase in thickening of the arterial wall. Inflammation and calcium mobilization are factors closely associated with the accelerated arterial wall changes.
Turnover of type II collagen and aggrecan in cartilage matrix at the onset of inflammatory arthritis in humans: Relationship to mediators of systemic and local inflammation
Authors: Fraser Alexander , Fearon Ursula , Billinghurst R. Clark , Ionescu Mirela , Reece Richard , Barwick Thomas , Emery Paul , Poole A. Robin , Veale Douglas J.
Published: November 2003

Objective

To determine in vivo the extent of damage to, and changes in turnover of, articular cartilage type II collagen (CII) and the proteoglycan aggrecan following the onset of inflammatory arthritis in humans, and to examine the hypothesis that there are direct relationships between cartilage biomarkers of damage/turnover and clinical, histologic, and molecular markers of inflammation.

Methods

Synovial fluid (SF) and synovial membrane (SM) were obtained by arthroscopy, and a synovitis score was determined, in 32 patients with rheumatoid arthritis (RA) (13 with early untreated disease, 19 with established disease), 18 with psoriatic arthritis (PsA), and 10 with osteoarthritis (OA). Systemic disease activity markers were recorded, and SM CD3+ T cells, CD4+ T cells, CD68+ macrophages, and lining layer hyperplasia were quantified. SF levels of tumor necrosis factor α (TNFα), interleukin‐10 (IL‐10), matrix metalloproteinase 1 (MMP‐1), MMP‐3, Col2‐3/4CLong mono neoepitope (C2C) (reflecting collagenase cleavage of cartilage CII), C‐propeptide of type II procollagen (PIICP) (a biosynthesis marker), keratan sulfate (KS), and the 846 epitope of aggrecan (turnover) were measured by enzyme‐linked immunosorbent assay or radioimmunoassay.

Results

Levels of cartilage degradation products in early RA or early PsA were not elevated above levels in OA, although in early inflammatory arthritis, TNFα and MMP‐1 levels were similar to those observed in late inflammatory disease and higher than those in OA. PIICP was reduced in early RA. Correlations were observed between the SF C2C neoepitope level and the Health Assessment Questionnaire score, C‐reactive protein level, plasma viscosity, synovitis score, and SF TNFα and MMP‐1 levels. KS epitope content was reduced in direct relation to SM macrophage infiltration in the sublining and lining layers and in the presence of elevated SF MMP‐3. Both SF MMP‐1 and SF MMP‐3 levels correlated with CD4+ T cell infiltration and lining layer hyperplasia in the SM, and MMP‐1 levels correlated with lining layer CD68 levels, but TNFα and IL‐10 levels did not.

Conclusion

Except for CII synthesis, there were no significant changes in extracellular matrix turnover of aggrecan or CII in the early stages of human inflammatory arthritis. However, the direct correlation between the increases in TNFα and MMP‐1 production and collagen degradation suggests that collagenase cleavage of cartilage collagen is related to the activities of TNFα and MMP‐1. The reduction in CII synthesis in early RA may contribute to the developing pathology, since a lack of synthesis of this molecule would inhibit maintenance of cartilage matrix.
Inhibition of the thrombogenic and inflammatory properties of antiphospholipid antibodies by fluvastatin in an in vivo animal model
Authors: Ferrara Dardo E. , Liu Xiaowei , Espinola Ricardo G. , Meroni Pier Luigi , Abukhalaf Imad , Harris E. Nigel , Pierangeli Silvia S.
Published: November 2003

Objective

Antiphospholipid antibodies (aPL) have thrombogenic properties in vivo, through their interactions with soluble coagulation factors and their ability to modulate the functions of cells involved in coagulation homeostasis. These antibodies have also been shown to enhance the adhesion of leukocytes to endothelial cells (ECs) in vivo. New lipophilic statins such as fluvastatin have antiinflammatory and antithrombogenic effects. This study uses an in vivo mouse model to investigate whether fluvastatin has an effect on decreasing both the adhesion of leukocytes to ECs and the thrombus formation induced by aPL.

Methods

Two groups of CD‐1 male mice, each comprising ∼18 mice, were fed either normal saline solution or 15 mg/kg fluvastatin for 15 days. Each of the 2 groups was further subdivided to receive either purified IgG from patients with the antiphospholipid syndrome (IgG‐APS) or normal IgG from healthy subjects. Analysis of thrombus dynamics was performed in treated and control mice, using a standardized thrombogenic injury procedure, and the area (size) of the thrombus was measured. Adhesion of leukocytes to ECs was analyzed with a microcirculation model of exposed cremaster muscle. Baseline and posttreatment soluble intercellular adhesion molecule 1 (sICAM‐1) levels were determined by enzyme‐linked immunosorbent assay.

Results

IgG‐APS mice treated with fluvastatin showed significantly smaller thrombi, a reduced number of adherent leukocytes, and decreased levels of sICAM‐1 compared with IgG‐APS animals treated with placebo.

Conclusion

These findings indicate that fluvastatin significantly diminishes aPL‐mediated thrombosis and EC activation in vivo. These results may have important implications for the design of new treatment strategies aimed at preventing recurrent thrombosis in patients with APS.
Inspirations and aspirations of exemplarian action research
Authors: Coenen Harry , Khonraad Sjaak
Published: November 2003

As a methodology aimed to focus social scientific theorizing on actual social problems and examine new directions and guidelines for emancipation and empowerment, action research is based on a joint learning process of researchers and researched. The model of exemplarian action research tries to capture how this learning process can develop in practice. Before describing this model and its emancipatory aspirations, the authors sketch the theoretical inspirations of the model of exemplarian action research. They then go on to focus on the relationship between researcher and the researched party, particularly on the principles of reciprocal adequacy and explicitness which are necessary both from an epistemologically and critical point of view. The article concludes by outlining some aspects in which exemplarian action research can be distinguished from pragmatic action research and by emphasizing that it does not stand for a post‐modern position, but for a reflexive attitude that hopes to contribute to bringing us beyond a half‐modern society. Copyright © 2003 John Wiley & Sons, Ltd.
The development of an individual, demand driven approach in a long‐lasting exemplarian action research
Authors: Valkenburg Ben
Published: November 2003

In this contribution, the author aims to elucidate the core aspects of the individual, demand driven approach and the way this approach has been developed in action research projects spanning more than 15 years. First the authors describe the developments towards more client centred approaches of labour‐market policies and care, which formed the background against which the individual, demand driven approach took shape. Then the authors sketch the main characteristics of the action research programme they have been involved in. As an example one of the projects of this programme will be elaborated further. In the fourth section of this contribution the authors give an overview of the four most distinctive aspects of the individual, demand driven approach. Then closes of with a few evaluative remarks. Copyright © 2003 John Wiley & Sons, Ltd.
Emancipatory design choices for action research practitioners
Authors: Roberts Gerry , Dick Bob
Published: November 2003

The process choices made in action research can determine how emancipatory an experience it is for participants. Some choices promote an experience of emancipation. Other choices can reduce it. There can be tensions between choices that encourage emancipation and those that pursue other advantages at the expense of emancipation. Here we consider six such tensions.

For each choice we suggest how to frame the tension to deliver an experience of emancipation. The suggestions involve practitioners and participants choosing the driving force for the work, acquiring and applying skills for empowerment, mixing action and research to suit the context, choosing an appropriate simplicity of methodology, planning participation, and engaging with the different beliefs of practitioners and participants. We use practitioner and researcher interchangeably. Copyright © 2003 John Wiley & Sons, Ltd.
Helping others: project or research?
Authors: De Zeeuw Gerard
Published: November 2003

Helping shows itself as most difficult—as in the exemplary query whether to help by providing the fish or the fishing‐rod. Action research and similar approaches were developed to answer the question what helps the helper. Each provides structure—project‐like, partly starting from science, partly from emancipatory ideology—structure to stimulate personal resources, structure to test, structure to give voice to helpees.

This article identifies ways to improve on this structure by the construction of collectives that help increase competences (enable), at the same time providing a method to test whether this succeeds. Such self‐correcting collectives constitute knowledge systems for users to participate in. Emancipation appears directly linked to the number of such systems ([knowledges]) in which people are able to participate simultaneously, each helping to maintain a stable view point. Copyright © 2003 John Wiley & Sons, Ltd.
Stabilisation of RNA Bulges by Oligonucleotide Complements Containing an Adenosine Analogue
Authors: Madder Annemieke , Ehrl Robert , Strömberg Roger
Published: November 2003

Incorporation of 2′‐deoxy‐2′‐β‐(1‐naphthylmethyl)tubercidin into an oligodeoxyribonucleotide mostly has little or a slightly negative effect on the Tm values of complexes with DNA complements. With the same naphthylmethyl‐substituted nucleoside at the 3′‐end of a 2′‐O‐methyloligoribonucleotide, however, a stabilisation of 1–2 °C in the corresponding complexes with both DNA and RNA is observed. When the target sequence is an RNA fragment forming a two‐ or three‐nucleotide bulge, complexes with (naphthylmethyl)tubercidin‐modified oligodeoxyribonucleotides, as well as with the corresponding 2′‐O‐methyloligoribonucleotides, give stabilisations of 1–2 °C for the three‐nucleotide bulge and of almost 4 °C for the two‐nucleotide bulge. This stabilisation is specific to RNA, since the corresponding complexes with the DNA fragments do not display this effect. Thus, the (naphthylmethyl)tubercidin‐containing oligonucleotides are the first reported oligonucleotide modifications that specifically stabilise bulged RNA.
New Light on a Long‐Known Protein Family
Authors: Andersen Olav M. , Petersen Helle H.
Published: November 2003

A family affair: The view of the LDLR family has shifted from a family of endocytosis receptors towards a class of membrane proteins participating in complex signaling pathways. The receptors play essential roles in several physiological processes but are also involved in many pathological events, such as atherosclerosis and Alzheimer's disease; this makes them attractive drug targets.
Evidence for the Combined Participation of a C10 and a C15 Precursor in the Biosynthesis of Moenocinol, the Lipid Part of the Moenomycin Antibiotics
Authors: Neundorf Ines , Köhler Christian , Hennig Lothar , Findeisen Matthias , Arigoni Duilio , Welzel Peter
Published: November 2003

Upon feeding of [2‐13C,4‐2H]‐1‐deoxy‐D‐xylulose to Streptomyces ghanaensis, the deuterium label was retained exclusively at positions C‐7 and C‐17 in the moenocinol part of the moenomycin antibiotics. This result vindicates the hypothesis that the C25 structure of moenocinol is assembled from a C10 and a C15 precursor, each of which requires for its formation the involvement of a dimethylallyl diphosphate starter unit.
A Cyclic CCK8 Analogue Selective for the Cholecystokinin Type A Receptor: Design, Synthesis, NMR Structure and Binding Measurements
Authors: De Luca Stefania , Ragone Raffaele , Bracco Chiara , Digilio Giuseppe , Aloj Luigi , Tesauro Diego , Saviano Michele , Pedone Carlo , Morelli Giancarlo
Published: November 2003

A cyclic CCK8 analogue, cyclo29,34[Dpr29,Lys34]‐CCK8 (Dpr=L‐2,3‐diaminopropionic acid), has been designed on the basis of the NMR structure of the bimolecular complex between the N‐terminal fragment of the CCKA receptor and its natural ligand CCK8. The conformational features of cyclo29,34[Dpr29,Lys34]‐CCK8 have been determined by NMR spectroscopy in aqueous solution and in water containing DPC‐d38 micelles (DPC=dodecylphosphocholine). The structure of the cyclic peptide in aqueous solution is found to be in a relaxed conformation, with the backbone and Dpr29 side chain atoms making a planar ring and the N‐terminal tripeptide extending approximately along the plane of this ring. In DPC/water, the cyclic peptide adopts a “boat‐shaped” conformation, which is more compact than that found in aqueous solution. The cyclic constraint between the Dpr29 side chain and the CCK8 carboxyl terminus (Lys34) introduces a restriction in the backbone conformational freedom. However, the interaction of cyclo29,34[Dpr29,Lys34]‐CCK8 with the micelles still plays an important role in the stabilisation of the bioactive conformation. A careful comparison of the NMR structure of the cyclic peptide in a DPC micelle aqueous solution with the structure of the rationally designed model underlines that the turn‐like conformation in the Trp30–Met31 region is preserved, such that the Trp30 and Met31 side chains can adopt the proper spatial orientation to interact with the CCKA receptor. The binding properties of cyclo29,34[Dpr29,Lys34]‐CCK8 to the N‐terminal receptor fragment have been investigated by fluorescence spectroscopy in a micellar environment. Estimates of the apparent dissociation constant, Kd, were in the range of 70–150 nM, with a mean value of 120±27 nM. Preliminary nuclear medicine studies on cell lines transfected with the CCKA receptor indicate that the sulfated‐Tyr derivative of cyclo29,34[Dpr29,Lys34]‐CCK8 displaces the natural ligand with an IC50 value of 15 μM.
NMR Structure of the (+)‐CPI‐indole/d(GACTAATTGAC)‐d(GTCAATTAGTC) Covalent Complex
Authors: Bassarello Carla , Cimino Paola , Bifulco Giuseppe , Boger Dale L. , Smith Jarrod A. , Chazin Walter J. , Gomez‐Paloma Luigi
Published: November 2003

We report the NMR solution structure of (+)‐CPI‐indole (CPI, 1,2,8,8a‐tetrahydrocyclopropa[c]pyrrolo[3,2‐e]indol‐4(5H)‐one), an agent belonging to the CC‐1065/duocarmycin family of antitumor compounds. This (+)‐CPI‐indole structure is covalently bound to d(G1ACTAATTGTC11)‐d(G12TCAATTAGTC22), a synthetic DNA duplex containing a high‐affinity binding site. The three‐dimensional structure has been determined by several cycles of restrained molecular dynamics calculations with a total of 563 NMR‐derived constraints, both in vacuo and by using the generalized Born solvent continuum model. In‐depth analysis of the structure of this ligand–DNA complex led to a detailed knowledge of the bound state conformation of the CPI‐indole, the most simplified agent related to CC‐1065 and duocarmycins, the parent members of a family of extremely potent antitumor compounds. Comparison of the CPI‐indole bound conformation with those previously found for (+)‐duocarmycin SA (DSA), its unnatural enantiomer (−)‐DSA, and the demethoxylated analogue (+)‐DSI in their DNA complexes provided additional evidence of the tight correlation between the catalytic effect exerted by DNA on the alkylation reaction and the extent of angular twist between the two planar heteroaromatic subunits of these agents. Additionally, comparison of the structural features of the DNA‐bound state of a “naked” ligand, such as CPI‐indole, with those of various other duocarmycin agents provided useful information for the interpretation of the observed effects on chemical reactivity of the different substitution patterns at the hemispheres of these types of complex.
Induction of Cell Death of Gastric Cancer Cells by a Modified Compound of the Annonaceous Acetogenin Family
Authors: Huang Guo‐Rui , Jiang Sheng , Wu Yu‐Lin , Jin Yan , Yao Zhu‐Jun , Wu Jia‐Rui
Published: November 2003

Annonaceous acetogenins are a family of natural products with antitumor activities. The polyether mimic AA005 has been synthesized. The cytotoxic mechanism of AA005 was investigated. It was found that AA005 can induce the cell death of gastric tumor cells. Most AA005‐induced cell death is due to necrosis but partial and p53‐independent apoptosis is also detected. An expanded study with gastric tumor cells and a cell‐free system indicates that AA005 affects NADH:ubiquinone oxidoreductase (complex I; NADH=nicotinamide adenine dinucleotide, reduced form) in the mitochondrial electron transport system. These results show for the first time that the polyether mimic AA005 acts on the same biological target as the natural annonaceous acetogenins.
Cover Picture: A Cyclic CCK8 Analogue Selective for the Cholecystokinin Type A Receptor: Design, Synthesis, NMR Structure and Binding Measurements (ChemBioChem 11/2003)
Authors: De Luca Stefania , Ragone Raffaele , Bracco Chiara , Digilio Giuseppe , Aloj Luigi , Tesauro Diego , Saviano Michele , Pedone Carlo , Morelli Giancarlo
Published: November 2003

The cover picture shows a molecular model of the interaction between the new CCK8 analogue, Cycle29,34[Dpr29,Lys34]‐CCK8 (shown as a CPK model) and the receptor fragment CCKA‐R(1–47) (represented by a pink ribbon). The introduction of the cyclic constraint between the Dpr29 sidechain and the CCK8 C terminus (Lys34) decreases the flexibility of the molecule to stabilize the bioactive conformation of Cycle29,34[Dpr29,Lys34]‐CCK8. The Trp30 and Met31 side chains are in favorable orientations for interaction with the CCKA receptor. Expansions of the aromatic/amide regions of the 1H NMR spectra of Cycle29,34[Dpr29,Lys34]‐CCK8 in aqueous solution (top) and in presence of dodecylphosphocholine‐d38 micelles (bottom) are shown in the inset. Further details can be found in the article by Morelli and co‐workers on p. 1176 ff.
Mechanism of Hydroxyl Radical‐Induced Breakdown of the Herbicide 2,4‐Dichlorophenoxyacetic Acid (2,4‐D)
Authors: Peller Julie , Wiest Olaf , Kamat Prashant V.
Published: November 2003

Oxidative transformations by the hydroxyl radical are significant in advanced oxidation processes for the breakdown of organic pollutants, yet mechanistic details of the reactions are lacking. A combination of experimental and computational methods has been employed in this study to elucidate the reactivity of the hydroxyl radical with the widely used herbicide 2,4‐D (2,4‐dichlorophenoxyacetic acid). The experimental data on the reactivity of the hydroxyl radical in the degradation of the herbicide 2,4‐D were obtained from γ‐radiolysis experiments with both 18O‐labeled and unlabeled water. These were complemented by computational studies of the .OH attack on 2,4‐D and 2,4‐DCP (2,4‐dichlorophenol) in the gas phase and in solution. These studies firmly established the kinetically controlled attack ipso to the ether functionality as the main reaction pathway of .OH and 2,4‐D, followed by homolytic elimination of the ether side chain. In addition, the majority of the early intermediates in the reaction between the hydroxyl radical and 2,4‐DCP, the major intermediate, were identified experimentally. While the hydroxyl radical attacks 2,4‐D by .OH‐addition/elimination on the aromatic ring, the oxidative breakdown of 2,4‐DCP occurs through .OH addition followed by either elimination of chlorine or formation of the ensuing dichlorophenoxyl radical.
Investigation of the Origin of Selectivity in Cavitand‐Based Supramolecular Sensors
Authors: Paolesse Roberto , Di Natale Corrado , Nardis Sara , Macagnano Antonella , D'Amico Arnaldo , Pinalli Roberta , Dalcanale Enrico
Published: November 2003

The sensing properties of functionalized cavitands have been studied by thin‐film coating TMSR chemical sensors and by measuring their responses towards model analytes. We studied the relationship between the sensor performance, in terms of sensitivity and selectivity, and the molecular recognition properties of the cavitands. The Langmuir‐like shape of the adsorption isotherm, obtained in the case of short‐chain alcohols, demonstrated that selective binding can be achieved by the synergistic interactions of the cavity and the bridging POin groups. In the absence of these substituents, the peripheral alkyl chains necessary for the formation of highly permeable thin films attenuate the cavity effect because of nonspecific dispersion interactions. This completely overrides the response originating from molecular recognition. The same effect is observed when the PO groups are oriented outward from the cavity. The use of multivariate chemometrics and the study of the correlations between sensors sensitivity and analyte properties provided further evidence of molecular recognition phenomena, whose intensity is enhanced by the permanent free volume created by the rigid cavity surrounding the POin group.
Intrinsically Stable Secondary Structure Elements of Proteins: A Comprehensive Study of Folding Units of Proteins by Computation and by Analysis of Data Determined by X‐ray Crystallography
Authors: Perczel András , Jákli Imre , Csizmadia Imre G.
Published: November 2003

Different protein architectures show strong similarities regardless of their amino acid composition: the backbone folds of the different secondary structural elements exhibit nearly identical geometries. To investigate the principles of folding and stability properties, oligopeptide models (that is, HCO‐(NH‐L‐CHR‐CO)n‐NH2) have been studied. Previously, ab initio structure determinations have provided a small amount of information on the conformational building units of di‐ and tripeptides. A maximum of nine differently folded backbone types is available for any natural α‐amino acid residue, with the exception of proline. All of these conformers have different relative energies. The present study compiles an ab inito database of optimized HCO‐(L‐Xxx)n‐NH2 structures, where 1≤n≤8 and Xxx=Ala or Gly. All homoconformers (α helix, β sheet, collagen helix, etc.) of the different backbone folds were optimized, along with additional β‐turn‐type heteroconformers. The comprehensive analysis of more than 150 fully optimized polyalanine and polyglycine structures reveals the same energy‐preference profile of major secondary structures as is found in globular proteins. The analysis of relative energies at three different levels of theory (RHF/3‐21G, RHF/6‐311++G(d,p)//RHF/3‐21G, and RHF/6‐311++G(d,p)) for the above‐mentioned achiral (Xxx=Gly) and chiral (Xxx=Ala) molecular structures shows how these common secondary structure elements gradually become more and more stable folds in the oligopeptides as the length of the peptide chain increases. This indicates that stability (local energy preference) of conformational building units seems to be a major driving force in peptide and protein folding. Furthermore, the preferred conformers of the gas phase are rather similar to those observed in proteins crystallized from aqueous media. Indeed, the relative energies for the different computed conformers show remarkable agreement with the frequency of occurrence of the same structural motifs retrieved from a nonhomologous X‐ray crystallography database.
Synthesis and Characterization of Carboxylate Complexes of SnIV Porphyrin Monomers and Oligomers
Authors: Hawley Joanne C. , Bampos Nick , Sanders Jeremy K. M.
Published: November 2003

Most of the porphyrin‐recognition chemistry we have investigated previously has centred on kinetically labile metal–ligand interactions, such as ZnN and RuN. Our interest in the broader scope of molecular recognition required a metal with the ability to specifically recognise non‐nitrogen‐based ligands, with a significantly different binding interaction to distinguish it from nitrogen‐based analogues. In this report we describe interactions of SnIV porphyrins that bind oxygen‐based ligands and for which the SnIVO bond is in slow exchange on the NMR timescale. A series of carboxylate complexes is employed to highlight the structural/geometric features of porphyrin monomers and cyclic oligomers. Where more than one porphyrin unit is present in a molecular scaffold, we report the effect of carboxylate binding on the complex when the two porphyrins contain different metals (typically SnIV and ZnII). The unexpected spectroscopic and structural properties of the Sn2(9‐anthroic acid)porphyrin dimer are also reported.
Addition Reaction of Vinylic Reagents, Derived from α‐Chloroenones, to Carbonyl Compounds Promoted by Samarium Diiodide
Authors: Concellón José M. , Bernad Pablo L. , Huerta Mónica , García‐Granda Santiago , Díaz M. Rosario
Published: November 2003

A new samarium diiodide‐promoted addition reaction of vinylsamarium reagents, derived from (Z)‐α‐chloro‐α,β‐unsaturated phenones 1, to both ketones (in THF) and aldehydes (in acetonitrile) led to (Z)‐2‐(1‐hydroxyalkyl)‐2,3‐unsaturated ketones in good yield. These transformations took place with total or very high inversion of the stereochemistry of the CC double bond of the starting chloroenone, producing the Z diastereoisomer. A new methodology to prepare SmI2 in acetonitrile by sonic treatment of 1,2‐diiodoethane with Sm powder is also described. A mechanism to explain this transformation is proposed.
Effect of Chirality on the Structural Behaviour of Hydrogen‐Bonded n‐Alkylammonium Pyroglutamates in the Crystalline and Smectic State
Authors: Tsiourvas Dimitris , Paleos Constantinos M. , Skoulios Antoine
Published: November 2003

A set of optically active and racemic n‐alkylammonium pyroglutamates from dodecyl to octadecyl were synthesized and characterised. Their thermotropic polymorphism was investigated by polarizing optical microscopy, differential scanning calorimetry and dilatometry. Their structure in the crystalline and smectic state was analysed by X‐ray diffraction. The hydrogen bonding of the molecules in the crystalline and smectic layers was examined by infrared spectroscopy. The chirality control over the supramolecular self‐assembly of the molecules along with the homochiral and heterochiral architecture of the self‐assembled dimers are briefly discussed.