bluuebunny/crossref_metadata_2025 huggingface dataset:
Plant growth inhibitory activity of Lycoris radiata Herb. and the possible involvement of lycorine as an allelochemical
Authors: IQBAL ZAHIDA , NASIR HABIB , HIRADATE SYUNTARO , FUJII YOSHIHARU
Published: October 2006

Lycoris radiata Herb., a common medicinal plant of Far East Asia, was examined for its potential use in paddy weed control. The preliminary screening in greenhouse conditions indicated growth inhibitory activities. The emergence, root and shoot growth, and root dry weight of the bioassay species were reduced when grown in soil mixed with the leaves of L. radiata. Aqueous extracts of the fresh leaves at various concentrations inhibited the root and shoot growth of all tested plant species. To identify the active components, L. radiata ethanolic extract was subjected to bioassay‐guided fractionation, purification, and spectroscopic analysis. This process led to the isolation of lycorine as a potential allelochemical. The concentration of lycorine in the dry leaves of L. radiata is estimated to be 0.08%. It is possible that lycorine is exuded from the roots or leaches from the living or decomposing leaves, along with other numerous inhibitors, and inhibits the growth of neighboring or successional plants. These results suggest that L. radiata has the potential to inhibit plant growth and lycorine acts as one of the most important plant growth inhibitors. This plant can be grown as a ground cover plant and its dead leaves could be applied as cover mulch.
Characterization of aryl acylamidase activity from propanil‐resistant barnyardgrass (Echinochloa crus‐galli [L.] Beauv.)
Authors: HIRASE KANGETSU , HOAGLAND ROBERT E.
Published: October 2006

The enzyme, aryl acylamidase, was characterized in propanil‐susceptible and propanil‐resistant barnyardgrass with respect to kinetic parameters, the effects of inhibitors, and the levels of activity in dark‐ and light‐grown tissues. The enzyme reaction in the resistant tissue preparation proceeded linearly with time over a 5 h time course, while activity in the susceptible tissue preparation was 2‐ to 4‐fold lower and the activity tended to decrease after 2 h. The apparent Km values were 62.1 mmol L−1 and 3.1 mmol L−1 for the enzyme activity in the susceptible and resistant tissue preparations, respectively. Two herbicides (anilofos and piperophos), previously shown to synergize propanil injury against the resistant biotype, were found to be potent inhibitors of the in vitro aryl acylamidase activity.
Expression of chemokine receptors on peripheral blood mononuclear cells of patients with immune‐mediated neuropathies treated with intravenous immunoglobulins
Authors: Trebst C. , Brunhorn K. , Lindner M. , Windhagen A. , Stangel M.
Published: October 2006

Intravenous immunoglobulin (IVIg) is an efficacious treatment for immune‐mediated neuropathies like Guillain–Barré syndrome (GBS), chronic inflammatory demyelinating neuropathy (CIDP), and multifocal motor neuropathy (MMN). In the pathogenesis of immune‐mediated neuropathies chemokines and their receptors play a crucial role. Using flow cytometry we examined whether IVIg modulates chemokine expression repertoires of T cells and monocytes. The expression of inflammatory chemokine receptors CCR1, CCR2, CCR4, CCR5, CCR6 and CXCR3 was investigated on circulating T‐cell subsets, and CCR1, CCR2 and CCR5 on circulating monocytes before and after IVIg treatment in patients with immune‐mediated neuropathies (MMN, n = 7; GBS, n = 1; CIDP, n = 2). Furthermore, the homing potential of T cells was analyzed by the expression of CCR7, a chemokine receptor known to be utilized by mature T cells to recirculate into secondary lymphoid organs. In contrast to studies in chronic heart failure, no differences in expression patterns before and after IVIg treatment of any of the investigated chemokine receptors were found. Furthermore, the proportion of CD45RO‐positive CD4+ or CD8+ T‐cell subsets was not changed by IVIg treatment. Thus, we concluded that modulation of the expression of chemokine receptors on circulating leukocytes by IVIg is not a mode of action in immune‐mediated neuropathies.
The Category Cued Recall test in very mild Alzheimer's disease: discriminative validity and correlation with semantic memory functions
Authors: Vogel A. , Mortensen E. L. , Gade A. , Waldemar G.
Published: October 2006

Episodic memory tests that measure cued recall may be particularly effective in the diagnosis of early Alzheimer's disease (AD) because they examine both episodic and semantic memory functions. The Category Cued Recall (CCR) test provides superordinate semantic cues at encoding and retrieval, and high discriminative validity has been claimed for this test. The aim of this study was to investigate the discriminative validity for this test when compared with the 10‐word memory list from Alzheimer's Disease Assessment Scale (ADAS‐cog) that measures free recall. The clinical diagnosis of AD was taken as the standard. It was also investigated whether the two episodic memory tests correlated with measures of semantic memory. The tests were administered to 35 patients with very mild AD (Mini Mental State Examination score > 22) and 28 control subjects. Both tests had high sensitivity (>88%) with high specificity (>89%). One out of the five semantic memory tests was significantly correlated to performances on CCR, whereas delayed recall on the ADAS‐cog memory test was significantly correlated to two semantic tests. In conclusion, the discriminative validity of the CCR test and the ADAS‐cog memory test was equivalent in very mild AD. This may be because CCR did not tap more semantic processes, which are impaired in the earliest phases of AD, than a test of free recall.
Relevance of 10‐min delayed recall in dementia screening
Authors: De Rotrou J. , Battal‐Merlet L. , Wenisch E. , Chausson C. , Bizet E. , Dray F. , Lenoir H. , Rigaud A.‐S. , Hanon O.
Published: October 2006

Within the context of early diagnosis of Alzheimer's disease (AD), there is a growing interest in neuropsychological screening tests. Amongst these tests, we focused on the largely used Memory Impairment Screen (MIS). The objective of the present work was to show that adding a 10‐min delayed recall to the MIS, improves the test psychometric characteristics in order to detect dementia in the earliest stages. A prospective study was carried out on a cohort of 270 consecutive elderly ambulatory subjects attending the Broca Hospital Memory Clinic: normal controls (n = 67), mild cognitive impairment subjects (n = 98) and mildly demented patients [n = 105, Mini Mental State Examination (MMSE) = 23 ± 4]. This study consisted in testing the advantage of the 10‐min delayed recall entitled MIS‐D compared with the MIS. At a cut‐off score of 6, the MIS‐D revealed satisfying psychometric characteristics with a sensitivity of 81% and a specificity of 91%, whilst the MIS alone indicated a sensitivity of 60% and a specificity of 88% in detecting dementia. In demented patients with MMSE score ≥26, MIS‐D properties still remained satisfying (sensitivity: 75%, specificity: 92%). MIS‐D is a more relevant screening test than MIS alone at very early stages of dementia.
The influence of anaemia on stroke prognosis and its relation to N‐terminal pro‐brain natriuretic peptide
Authors: Nybo M. , Kristensen S. R. , Mickley H. , Jensen J. K.
Published: October 2006

Anaemia is a negative prognostic factor for patients with heart failure and impaired renal function, but its role in stroke patients is unknown. Furthermore, anaemia has been shown to influence the level of N‐terminal pro‐brain natriuretic peptide (NT‐proBNP), but this is only investigated in patients with heart failure, not in stroke patients. Two‐hundred‐and‐fifty consecutive, well‐defined ischemic stroke patients were investigated. Mortality was recorded at 6 months follow‐up. Anaemia was diagnosed in 37 patients (15%) in whom stroke severity was worse than in the non‐anaemic group, whilst the prevalence of renal affection, smoking and heart failure was lower. At 6 months follow‐up, 23 patients were dead, and anaemia had an odds ratio of 4.7 when adjusted for age, Scandinavian Stroke Scale and a combined variable of heart and/or renal failure and/or elevation of troponin T using logistic regression. The median NT‐proBNP level in the anaemic group was significantly higher than in the non‐anaemic group, and in a multivariate linear regression model, anaemia remained an independent predictor of NT‐proBNP. Conclusively, anaemia was found to be a negative prognostic factor for ischemic stroke patients. Furthermore, anaemia influenced the NT‐proBNP level in ischemic stroke patients, an important aspect when interpreting NT‐proBNP in these patients.
A Modified Bayes Information Criterion with Applications to the Analysis of Comparative Genomic Hybridization Data
Authors: Zhang Nancy R. , Siegmund David O.
Published: October 2006

SummaryIn the analysis of data generated by change‐point processes, one critical challenge is to determine the number of change‐points. The classic Bayes information criterion (BIC) statistic does not work well here because of irregularities in the likelihood function. By asymptotic approximation of the Bayes factor, we derive a modified BIC for the model of Brownian motion with changing drift. The modified BIC is similar to the classic BIC in the sense that the first term consists of the log likelihood, but it differs in the terms that penalize for model dimension. As an example of application, this new statistic is used to analyze array‐based comparative genomic hybridization (array‐CGH) data. Array‐CGH measures the number of chromosome copies at each genome location of a cell sample, and is useful for finding the regions of genome deletion and amplification in tumor cells. The modified BIC performs well compared to existing methods in accurately choosing the number of regions of changed copy number. Unlike existing methods, it does not rely on tuning parameters or intensive computing. Thus it is impartial and easier to understand and to use.
Assessing the Implications of Publication Bias for Two Popular Estimates of between‐Study Variance in Meta‐Analysis
Authors: Jackson Dan
Published: October 2006

Summary Perhaps the greatest threat to the validity of a meta‐analysis is the possibility of publication bias, where studies with interesting or statistically significant results are more likely to be published. This obviously impacts on inference concerning the treatment effect but also has implications for estimates of between‐study variance. Two popular and established estimation methods are considered and formulae for assessing the implications of the bias are provided in terms of a general process for selecting studies. Meta‐analysts, concerned that publication bias may be present, can use these as part of a sensitivity analysis to assess the robustness of their estimates of between‐study variance using any selection process that is likely to be used in practice. The procedure is illustrated using a meta‐analysis of clinical trials concerning the effectiveness of endoscopic sclerotherapy for preventing death in patients with cirrhosis and oesophagogastric varices.
ON THE HOPF STRUCTURE OF W2-ALGEBRA AND N = 1 SUPERCONFORMAL ALGEBRA IN THE OPE LANGUAGE
Authors: ÖZER H. T.
Published: October 2006

Hopf structure of the prototype realizations of the W2-algebra and also N = 1 superconformal algebra are obtained using the bosonic and also fermionic Feigin–Fuchs type of free massless scalar fields in the operator product expansion (OPE) language.
GEOMETRIC HAMILTON–JACOBI THEORY
Authors: CARIÑENA JOSÉ F. , GRÀCIA XAVIER , MARMO GIUSEPPE , MARTÍNEZ EDUARDO , MUÑOZ-LECANDA MIGUEL C. , ROMÁN-ROY NARCISO
Published: October 2006

The Hamilton–Jacobi problem is revisited bearing in mind the consequences arising from a possible bi-Hamiltonian structure. The problem is formulated on the tangent bundle for Lagrangian systems in order to avoid the bias of the existence of a natural symplectic structure on the cotangent bundle. First it is developed for systems described by regular Lagrangians and then extended to systems described by singular Lagrangians with no secondary constraints. We also consider the example of the free relativistic particle, the rigid body and the electron–monopole system.
The Drug Development Crisis: Efficiency and Safety
Authors: Caskey C. Thomas
Published: October 2006

Despite advancements in genetics, chemistry, and protein engineering, recent years have seen fewer approvals of new drugs, increases in development costs, and high-profile drug withdrawals. This article focuses on technologic methods for improving drug development efficiency. These technologies include high-content cell screening, expression profiling, mass spectroscopy, mouse models of disease, and a post-launch screening program that enables investigations of adverse drug effects. Implementation of these new technologies promises to improve performance in drug development and safety.
Phosphorylation Energy Hypothesis: Open Chemical Systems and Their Biological Functions
Authors: Qian Hong
Published: October 2006

Biochemical systems and processes in living cells generally operate far from equilibrium. This review presents an overview of a statistical thermodynamic treatment for such systems, with examples from several key components in cellular signal transduction. Open-system nonequilibrium steady-state (NESS) models are introduced. The models account quantitatively for the energetics and thermodynamics in phosphorylation-dephosphorylation switches, GTPase timers, and specificity amplification through kinetic proofreading. The chemical energy derived from ATP and GTP hydrolysis establishes the NESS of a cell and makes the cell—a mesoscopic–biochemical reaction system that consists of a collection of thermally driven fluctuating macromolecules—a genetically programmed chemical machine.
Timing and Computation in Inner Retinal Circuitry
Authors: Baccus Stephen A.
Published: October 2006

In the vertebrate inner retina, the second stage of the visual system, different components of the visual scene are transformed, discarded, or selected before visual information is transmitted through the optic nerve. This review discusses the connections between higher-level functions of visual processing, mathematical descriptions of the neural code, inner retinal circuitry, and visual computations. In the inner plexiform layer, bipolar cells deliver spatially and temporally filtered input to approximately ten anatomical strata. These layers receive a unique combination of excitation and inhibition, causing cells in different layers to respond with different kinetics to visual input. These distinct temporal channels interact through amacrine cells, a diverse class of inhibitory interneurons, which transmit signals within and between layers. In particular, wide-field amacrine cells transmit transient inhibition over long distances within a layer. These mechanisms and properties are combined into computations to detect the presence of differential motion and suppress the visual effects of eye movements.
Long-Term Outcomes of Bilateral Subthalamic Nucleus Stimulation in Patients with Advanced Parkinson’s Disease
Authors: Liang Grace S. , Chou Kelvin L. , Baltuch Gordon H. , Jaggi Jurg L. , Loveland-Jones Catherine , Leng Lewis , Maccarone Heather , Hurtig Howard I. , Colcher Amy , Stern Matthew B. , Kleiner-Fisman Galit , Simuni Tanya , Siderowf Andrew D.
Published: October 2006

Background: In patients with advanced Parkinson’s disease (PD), deep brain stimulation (DBS) of the subthalamic nucleus (STN) has been shown to improve motor function and decrease medication requirements in the short term. However, the long-term benefits of DBS are not yet established. Objective: It was the aim of this study to evaluate long-term outcomes of patients with PD treated with bilateral DBS of the STN. Design and Methods: Thirty-three subjects who had bilateral STN DBS were followed prospectively after surgery. We evaluated subjects, using the Unified Parkinson’s Disease Rating Scale (UPDRS), preoperatively, 12 months after surgery and at a long-term follow-up visit. Ratings were performed on and off dopaminergic medications. We compared postoperative UPDRS scores, dyskinesia ratings and medication dosages with preoperative values. Results: Twenty-seven subjects had evaluations beyond 18 months (median 33.7 months). Total UPDRS scores in the ‘medication-off’ state were improved by 37% (p < 0.001) at 12 months and 17.7% (p = 0.0051) at the long-term evaluation. Medication-off state UPDRS part III scores were significantly improved at both 1 year and at the last evaluation (37.6 and 29.3%; p < 0.001). Dopaminergic medication requirements were decreased by 35.3% (p < 0.001) during the first postoperative year and remained below preoperative levels at the long-term evaluation. Average duration of ‘off’ time remained decreased by about 40% at both 1 year and at the time of last evaluation. Subjects had a sustained reduction in dyskinesia severity (88.6% at 1 year and 68.8% at last evaluation). Conclusions: In this cohort of subjects with advanced PD, bilateral STN stimulation improved ‘off’ medication motor function, reduced time spent in the medication-off state and reduced medication requirements for up to 4 years after surgery. We conclude that STN DBS is an effective long-term therapy for selected patients with advanced PD.
Haplotypes of the plasminogen activator gene associated with ischemic stroke
Authors: Saito Kosuke , Sato Naoyuki , Morita Akihiko , Takahashi Teruyuki , Soma Masayoshi , Usami Ron , Nakayama Tomohiro
Published: October 2006

Ischemic stroke (IS) is thought to be a multifactorial disorder associated with genetic backgrounds and environmental factors. In the circulating plasma, tissue plasminogen activator (tPA) catalyzes the reaction from plasminogen to plasmin. If there is a functional disability of tPA, induction of thrombosis and infarction disorders can occur. The aim of this study was to performa haplotype-based case-control study using single nucleotide polymorphisms (SNPs) in the human tPA gene, and to assess the association between the tPA gene and IS. We genotyped 182 IS individuals and 403 controls for five SNPs in the human tPA gene, rs7007329, rs732612, rs8178750, rs2020922, and rs4471024. Using these five SNPs, a haplotype-based case control study was performed. There were seven SNP combinations that exhibited significant differences in the overall distribution between the IS and control groups. Linkage disequilibrium analysis showed that the combination of rs7007329 and rs8178750 was useful in identification of the susceptibility haplotype. The frequency of the G-T haplotype at rs7007329-rs8178750 was significantly higher in the IS group (1.2%) as compared to the control group (0.0%) (p=0.003).Diplotype analysis also showeda significant association of the diplotype with the G-T haplotype at rs7007329-rs8178750 (OR:11.4, 95%CI:1.32–97.9, p=0.013). These results suggest that the G-T haplotype at rs7007329-rs8178750 of the tPA gene isa genetic marker for IS, and that tPA ora neighboring gene isa susceptibility gene for IS.
Psychological impact of testing for thrombophilic alterations
Authors: Razzaboni Elisabetta , Gremigni Paola , Bitti Pio Enrico , Favaretto Elisabetta , Palareti Gualtiero , Legnani Cristina
Published: October 2006

We investigated the psychological impact of testing for the presence of thrombophilic alterations. The enrolled subjects received counseling from a physician before blood sampling and after receiving results, with a view to provide clear information about the aim of thrombophilia screening (TS). Participants were requested to completea pre-test questionnaire during this interview and a post-test questionnaire 20 days after receiving theTS results. One hundred ninety-seven subjects completed the pre-test questionnaire and 140/197 (71.1%) returned the post-test one. The TS results were altered in 36 (25.7%, R506Q mutation n=19; G20210A mutation n=9; antithrombin deficiency n=1; LAC phenomenon n=4; hyperhomocysteinemia n=3) and normal in 104 subjects. We assessed: perceived health status (PHS), state of anxiety, health fears, depressive reactions, moods, perceived well-being, and perceived daily-life stress. For both groups, both at pre- and post-test, none of the psychological variable scores showed significant worsening, regardless of whether TS resulted altered or normal. Anxiety significantly (p≤0.05) decreased at post-test in the altered group and a nonsignificant improvement in PHS after TS result communication was recorded in both groups. Age was an important factor in mediating psychological impact. In conclusion, diagnosis of thrombophilic alterations seems to be well accepted in the short term and TS should not be discouraged for potential adverse psychological effects. However, the psychological impact over a longer period of receiving altered results needs to be further investigated. The relationship between absence of adverse psychological reactions and quality of counseling program provided before and after TS should also be investigated.
Identification of a new truncated form and deamidation products of fibrinopeptide B released by thrombin from human fibrinogen
Authors: Cardinali Barbara , Damonte Gianluca , Melone Luca , Salis Annalisa , Tosetti Francesca , Rocco Mattia , Profumo Aldo
Published: October 2006

Quantification of fibrinopeptides release is widely used to investigate fibrinogen activation, and standard chromatographic or capillary electrophoretic procedures are readily available. However, in the analyses of fibrinopeptide mixtures derived from the action of thrombin on human fibrinogen, a few unidentified peaks are usually present. The composition of these peaks was studied by reverse-phase HPLC/MS, revealing a single major anomalous peptide having a molecular mass of 1384.4. A further MS/MS analysis allowed the identification of this form, as a Nterminally truncated fibrinopeptideB (fpB) lacking the first two residues (pyroglutamic acid and glycine). This previously unidentified, relatively low-abundance form (∼7%) has been found consistently in our fibrinopeptides preparations, and analysis of the parent Bβ-chain suggest that it is likely present in circulating fibrinogen. In addition, deamidated forms of all fpB species (including desArgB), resulting from the conversion of asparagine to aspartic acid, were also identified. Overall, these previously unreported forms constitute a substantial amount of fpB (up to ∼17% of the total), and should be taken into account for a reliable quantitative analysis of fpB release.
Amplified anticoagulant activity of tissue factor-targeted thrombomodulin
Authors: Wu Chenliang , Vincelette Jon , Martin-McNulty Baby , Alexander Serene , Larsen Brent , Light David , McLean Kirk , Wang Yi-Xin
Published: October 2006

Tissue factor (TF) exposure isa potent pro-thrombotic trigger that initiates activation of the coagulation cascade, while thrombomodulin (TM) is a potent anticoagulant protein that limits the extent of activation. Both TF neutralizing antibodies and soluble TM (sTM) are effective anticoagulants. We have developed a novel anticoagulant fusion protein, Ab(TF)-TM, by fusing a TF-neutralizing single-chain antibody, Ab(TF), to an active fragment of TM. Ab(TF)-TM is a novel anticoagulant targeting to sites of TF exposure with a dual mechanism of action. The Ab(TF) portion of the molecule inhibits TF/factor VIIa mediated activation of FIX and FX, and the TM portion of the molecule acts as a cofactor for activation of protein C. In-vitro coagulation assays show that Ab(TF)-TM more potently inhibits TF-initiated coagulation (prothrombin time) than can its individual components, Ab(TF) (20-fold) and sTM (80-fold) alone, or in combination (10-fold). In contrast, the potency of Ab(TF)-TM in the activated partial thromboplastin and thrombin clotting time assays was similar to sTM alone. Ina rat model of disseminated intravascular coagulation (DIC), intravenous injection of a human TF-containing thromboplastin reagent (0.5 ml/kg) resulted in an immediate death in ∼60% of the animals and a clinical score of ∼2.5. Pre-injection of Ab(TF)-TM or Ab(TF) and sTM, given alone or in combination, showed dose-dependent efficacy. At a dose of 0.7 nmol/kg, Ab(TF)-TM completely prevented death and reduced clinical scores by 79%, while neither Ab(TF) nor sTM, given alone or in combination, showed significant therapeutic effects. Calculated effective doses that reduced mortality by 50% relative to that in the control group (ED50, nmol/kg) were 0.21 for Ab(TF)-TM, 3.2 for an equimolar mixture of Ab(TF) and sTM, 4.3 for sTM and 20 for Ab(TF). Thus, Ab(TF)-TM presented 10– to 100-fold enhancement of the anticoagulant potency, relative to the ED50 in Ab(TF) and sTM given either alone or in combination, in a rat DIC model.
Folic acid administration and antibodies against homocysteinylated proteins in subjects with hyperhomocysteinemia
Authors: Undas Anetta , Stïpień Ewa , Glowacki Rafal , Tisończyk Joanna , Tracz Wieslawa , Jakubowski Hieronim
Published: October 2006

Growing evidence indicates that elevated total homocysteine (tHcy) levels can elicit autoimmune response in vivo. Antibodies against Nε-Hcy-proteins have been shown to be associated with stroke and premature myocardial infarction. The aim of the current study was to investigate the effect of treatment with folic acid on anti-Nε-Hcy-albumin and -hemoglobin antibodies. We recruited 20 apparently healthy men and 12 male patients with documented coronary artery disease (CAD). All participants had plasma fasting tHcy levels >15 µM. At baseline, and after three and six months of treatment with folic acid 1 mg daily, we determined tHcy, serum folate and vitamin B12 levels, along with serum anti-Nε-Hcy-albumin and -hemoglobin IgG antibodies using the home-made immunoenzymatic assays. Both groups did not differ with regard to age, tHcy, folate, lipid profile, and CRP. The only significant difference between healthy subjects and CAD patients was levels of antibodies against Nε-Hcy-albumin. As expected, folic acid administration led to significant decreases in tHcy and increases in folate levels in both groups. Levels of both anti-Nε-Hcy-albumin and -hemoglobin antibodies fell markedly following a three-month folic acid administration in healthy subjects, but not in CAD patients, without any changes at six months in either group. Folic acid administration resulted in a loss of significant correlations between tHcy and antibodies both following three and six months of the therapy in healthy subjects, in contrast to CAD patients. Carriers of the methylenetetrahydrofolate reductase (MTHFR) 677T allele with CAD had significantly higher levels of anti-Nε-Hcy-albumin before and during folic acid administration as compared to healthy subjects. In conclusion, our findings suggest that Hcy-related autoimmune response is resistant to folic acid administration in CAD patients, while in healthy subjects reduced tHcy levels are associated with suppressed production of antibodies against Nε-Hcyproteins. These observations might explain at least in part the failure of vitamin therapy to reduce the risk of cardiovascular events as recently reported.
Antibody profile and clinical course in primary antiphospholipid syndrome with pregnancy morbidity
Authors: Ruffatti Amelia , Tonello Marta , Del Ross Teresa , Cavazzana Anna , Grava Chiara , Noventa Franco , Tona Francesco , Iliceto Sabino , Pengo Vittorio
Published: October 2006

In women diagnosed as having category I primary obstetric antiphospholipid syndrome, clinical characteristics and the risk of subsequent thromboembolic events and further unsuccessful pregnancy has not been clearly documented. Women with unexplained obstetric complications and no definite autoimmune systemic diseases were tested for lupus anticoagulant (LA), IgG/ IgM anticardiolipin (aCL) and IgG/IgM anti-human β2-Glycoprotein I (aβ2GPI) antibodies and diagnosed as having primary antiphospholipid syndrome (APS) in classification category I on the basis of more than one laboratory criteria present in any combination. Characteristics at the time of diagnosis and risk factors for subsequent clinical events during a mean follow-up of 6.3 years were evaluated. Fifty-three of 600 women studied were found to fulfil obstetric criteria and had more than one positive laboratory test at the time of diagnosis. All the women were a CL and aβ2GPI positive, and 16 were also LA positive. This latter group (triple positivity) had distinct features and had more frequently experienced previous thromboembolism (OR= 122.5, 95% CI 16–957, p<0.001).They also had an increased rate of late pregnancy loss (OR=16.2, 95%CI 0.9–292, p=0.01), and a higher IgG aβ2GPI titer at diagnosis (median, 25th and 75th percentile were 118, 37–962, vs. 23, 18–32, respectively, p<0.0001). During follow-up, the rate of thromboembolic events was significantly higher in the group of women with triple positivity and/ or previous thromboembolism (OR=57.5, 95% CI 2.7–1160, p=0.0004) which were the only independent predictors of TE in the multivariate model. Recurrent pregnancy loss took place in seven out of 47 women who had a new pregnancy. Triple positivity and/or previous thromboembolism were again the only independent markers (OR=34.4, 95% CI 3.5–335.1, p=0.003) of an unsuccessful new pregnancy. In conclusion, in primary APS with pregnancy morbidity in classification category I, quite different groups of patients may be identified on the basis of laboratory tests. Triple positivity and/or a history of thromboembolism predict new TE events and new unsuccessful pregnancies.
Identification of functional polymorphisms of the thromboxane A2 receptor gene in healthy volunteers
Authors: Fontana Pierre , Gandrille Sophie , Remones Véronique , Dupont Annabelle , Reny Jean-Luc , Aiach Martine , Gaussem Pascale
Published: October 2006

Thromboxane A2 receptor (TP) is an important actor in vascular physiology and plays a crucial role in the platelet activation process. Genetic polymorphisms of the gene coding for the TP have been described, but their impacts on platelet function tests are unknown. The aim of this study was to investigate the relationship between genetic polymorphisms of the coding sequence of the TP gene and platelet function tests. We investigated 100 healthy volunteers twice, one week apart by performing platelet aggregation and secretion tests. We sequenced the coding region of the TP gene and confronted the genetic variants with the phenotypic results. We identified five single nucleotide polymorphisms (SNP); one of them, T1712C, replaces Leu by Pro at position 133 of the isoform β of the TP. Homozygosity for the minor allele of the C795T, C924T or the G1686A SNP was associated with a decreased expression of CD62P when platelets were stimulated with the TP agonist U46619. As C795T and C924T have been linked to clinical disorders in which TxA2 plays a key role, the possible role of the G1686A and T1712C SNP should also be examined in selected diseases.
Racial and gender differences in the incidence of recurrent venous thromboembolism
Authors: Dager William , Zhou Hong , Murin Susan , White Richard
Published: October 2006

Men have been reported to have a higher incidence of recurrent venous thromboembolism than women. However, it is not known if this gender effect holds among different racial/ethnic groups and for both venous thrombosis and pulmonary embolism. We conducteda retrospective analysis of 18-to 65-year-old Caucasian, African-American and Hispanic cases hospitalized in California with unprovoked venous thromboembolism. The principal outcome was recurrent venous thromboembolism 7–60 months after the index event. Among 11,514 cases that were followed for a mean of 3.0 years, men had a significantly higher rate (events/100 patient-years) of recurrent venous thromboembolism than women for both venous thrombosis [rate ratio (RR)=1.5, 95% confidence interval (CI):1.3–1.8] and pulmonary embolism [RR=1.3, 95%CI:1.0–1.6].Among men the recurrence rate did not vary significantly between the racial/ethnic groups (p>0.05). However, the recurrence rate among Hispanic women with venous thrombosis was significantly higher than in Caucasian women (p<0.001) and was comparable to the rate in men. Both Hispanic and African-American women with pulmonary embolism had a higher recurrence rate compared with Caucasian women (p<0.02) that was comparable to the rate in men. We conclude that women in California had a 40% lower risk of recurrent venous thromboembolism compared to men. Rates were comparable among men of different races, but there were significant inter-racial differences among women, which also varied with the type of initial event. The effect of gender on the risk of recurrent venous thromboembolism can not be generalized because it varies between racial/ethnic groups and with the type of index event.
Skills in Australia: Towards Workforce Development and Sustainable Skill Ecosystems
Authors: Hall Richard , Lansbury Russell D.
Published: October 2006

This article argues that there is a need to move beyond narrow ways of thinking about training to incorporate broader notions of ‘workforce development’ and ‘skill ecosystems’. A market-based approach to skills development is contrasted with a social consensus model, which takes a more integrated view of how skills are formed and sustained. However, following a review of Australia’s brief and ultimately unsuccessful attempt to develop something akin to a social consensus approach, we argue that there is much to be gained from a workforce development approach and an understanding of skill formation as occurring in the context of skill ecosystems. To be most effective this approach to skill formation requires the facilitation of networks and nurturing of partnerships among the different agents and agencies concerned with skill development. Recent initiatives in Australia that explicitly adopt a skill ecosystem and workforce development orientation demonstrate the potential of these approaches to overcome many of the problems associated with currently dominant market-based approaches and avoid the pitfalls of social consensus models.
From Grounded Skills to Sky Qualifications: A Study of Workers Creating and Recreating Qualifications, Identity and Gender at an Underground Iron Ore Mine in Sweden
Authors: Abrahamsson Lena , Johansson Jan
Published: October 2006

Over a period of 50 years at Kiruna iron ore mine in the far north of Sweden we can see a transformation of work from underground to remote control at surface level. What characterized the old underground workface was the close relation between man and the hard rock centred on arduous physical work under dangerous conditions. Today, the face miners are located ‘up in the sky’ on the seventh level of an office building close to the mine. The workers leave their job at the end of the shift just as clean as when they arrived. The contact with the hard rock is mediated by machines controlled by remote control technology. The modern technology has created a new type of work - new in terms of competencies and knowledge as well as workload. The purpose of this article is to reflect on the technical development of underground mining in Kiruna and to consider the implications it has had on qualifications, identity and gender. There is an emerging, and in many aspects already evident, knowledge transformation - from the old and obsolete physical and tacit knowledge and skills (for example the ability to ‘read the rock’) to something new which can be described as abstract knowledge. But the old culture still provides an important context for workplace learning and the construction of identity and gender. This is associated with a degree of ‘worker identity lag’ and to difficulties in adapting attitudes and norms to the demands and structures that result from the new technology and the new work tasks. The new forms of work in the mine have less need for the traditional mining competencies, attitudes and ideals. The traditional workplace culture and its ‘macho style’ have also been challenged. Workers have to find new ways to learn and to develop a workplace culture more attuned to a new type of worker identity and masculinity.
Customizing Technology Transfer: Lessons to be Learned from Comparative Cross Cultural Studies
Authors: Backlund Ann-Katrin
Published: October 2006

This article highlights the old wisdom that technology is socially constructed. By using examples from a study of how German machinery manu-facturing firms and North American user industries act and think while developing and implementing advanced technology, and reflecting on these examples to elucidate Swedish manufacturing culture, the study highlights how knowledge about industrial behaviour can only be made visible by comparative studies, since only in relief - in contrast with something different - can the ‘taken for granted’ behaviour be identified. It is argued that identifying the prevailing industrial behaviour in a region opens up the possibility not only of identifying different strategies in inter-firm contacts but also of mastering them. Engineering that could ‘customize’ not only technology but also the interaction with customers and differentiate the service for different markets would have a competitive advantage.
Naltrexone and buprenorphine combination in the treatment of opioid dependence
Authors: Gerra G. , Fantoma A. , Zaimovic A.
Published: October 2006

Naltrexone treatment has demonstrated some advantages for special populations of heroin addicted individuals, but patients' compliance seems to be very poor, with a low adherence and low retention rate. Kappa-opioid system overdrive seems to contribute to opioid protracted abstinence syndrome, with dysphoria and psychosomatic symptoms during naltrexone treatment. The objective of this observational study was to determine the effectiveness of a functional k antagonist in improving naltrexone treatment outcome. A partial mu agonist/kappa antagonist (buprenorphine) and a mu antagonist (naltrexone) were combined during a 12 weeks protocol, theoretically leaving k antagonism as the major medication effect. Sixty patients were submitted to outpatient rapid detoxification utilizing buprenorphine and opioid antagonists. Starting on the fifth day, 30 patients (group A) received naltrexone alone. Alternatively, 30 patients (group B) received naltrexone (50mg oral dose) plus buprenorphine (4mg sublingual) for the 12 weeks of the observational study. The endpoints of the study were: retention in treatment, negative urinalyses, changes in psychological symptoms (Symptom Checklist-90 Revised: SCL-90) and craving scores (visual analysis scale (VAS)). Thirty-four subjects (56.67%) completed the 12 weeks study. Twenty-one patients (35.0%) had all urine samples negative for opiates and cocaine. nine subjects (15.0%) had urine samples negative for cocaine and opiates for the last 4 weeks of the study. five subjects (8.3%) continued to use cocaine during the 12 weeks of the study. No significant change in pupillary diameter after buprenorphine administration was evidenced during clinical observations from baseline across the weekly measurements. Retention rates in group A (naltrexone) and group B (naltrexone+ buprenorphine) at week 12 were respectively 40% (12 patients) and 73.33% (22 patients), with a significant difference in favour of group B ( p= 0.018). Patients treated with naltrexone in combination with buprenorphine (B patients) showed a significantly lower rate of positive urines for morphine (4.45%) and cocaine metabolites (9.09%) than those treated with naltrexone alone (A) (25%, morphine; 33.33% cocaine) ( p< 0.05; p< 0.05). Irritability, depression, tiredness, psychosomatic symptoms and craving scores decreased significantly less in Group A patients than in group B patients. The dysfunction of opioid system with kappa receptors hyper-activation provoked by heroin exposure, probably underlying dysphoric and psychosomatic symptoms during naltrexone treatment, seems to be counteracted, at least in part, by buprenorphine. The combination of buprenorphine and naltrexone may significantly improve the outcome of opioid antagonists treatment in terms of retention, negative urinalyses, and reduced dysphoria, mood symptoms and craving.
A Simple Algorithm for Complete Motion Planning of Translating Polyhedral Robots
Authors: Varadhan Gokul , Krishnan Shankar , Sriram T. V.N. , Manocha Dinesh
Published: October 2006

We present a new sampling-based algorithm for complete motion planning. Our algorithm relies on computing a star-shaped roadmap of the free space. We partition the free space into star-shaped regions such that a single point, called the guard, can see every point in the star-shaped region. The resulting set of guards capture the intra-region connectivity—the connectivity between points belonging to the same star-shaped region. We capture the inter-region connectivity by computing connectors that link guards of adjacent regions. The guards and connectors are combined to obtain the star-shaped roadmap. We present an efficient algorithm to compute the roadmap in a deterministic manner without explicit computation of the free space. We show that the star-shaped roadmap captures the connectivity of the free space, thereby enabling us to perform complete motion planning. Our approach is relatively simple to implement. We apply our approach to perform motion planning of robots with translational and rotational degrees of freedom (dof). We highlight its performance in challenging scenarios with narrow passages or when there is no collision-free path for robots with low degrees of freedom.
Synchronous Tracking Control of Parallel Manipulators Using Cross-coupling Approach
Authors: Sun D. , Lu R. , Mills J. K. , Wang C.
Published: October 2006

This paper presents a cross-coupled control approach to the tracking control of parallel manipulators in a synchronous manner. Based on the synchronization goal, the position synchronization error is investigated by considering motion synchronization between each actuator joint and its adjacent ones. A decentralized trajectory tracking controller is then developed with feedback of both position and synchronization errors, formed with a combination of feedforward, feedback and a saturation control. It is proven that this tracking controller can asymptotically stabilize both position and synchronization errors of the system. The proposed controller does not require the explicit use of the system dynamic model. Experiments performed on a 3-DOF parallel manipulator demonstrate improved performance with the proposed synchronous control design.
Optimal Mass Distribution for Passivity-Based Bipedal Robots
Authors: Hass J. , Herrmann J. M. , Geisel T.
Published: October 2006

This paper reports how and to what extent the mass distribution of a passive dynamic walker can be tuned to maximize walking speed and stability. An exploration of the complete parameter space of a bipedal walker is performed by numerical optimization, and optimal manifolds are found in terms of speed, the form of which can be explained by a physical analysis of step periods. Stability, quantified by the minimal basin of attraction, is also shown to be high along these manifolds, but with a maximum at only moderate speeds. Furthermore, it is examined how speed and stability change on different ground slopes. The observed dependence of the stability measure on the slope is consistent with the interpretation of the walking cycle as a feedback loop, which also provides an explanation for the destabilization of the gait at higher slopes. Regarding speed, an unexpected decrease at higher slopes is observed. This effect reveals another important feature of passive dynamic walking, a swing-back phase of the swing leg near the end of a step, which decreases walking speed on the one hand, but seems to be crucial for the stability of the gait on the other hand. In conclusion, maximal robustness and highest walking speed are shown to be partly conflicting objectives of optimization.
Evaluation of Cell Adhesion and Proliferation on a Novel Tissue Engineering Scaffold Containing Chitosan and Hydroxyapatite
Authors: Tachaboonyakiat Wanpen , Ogomi Daisuke , Serizawa Takeshi , Akashi Mitsuru
Published: October 2006

Porous chitosan-hxdroxyapatite hybrids were developed by partial enzymatic degradation [14] of the chitin/chitosan surface using chitosanase and lysozyme. This article evaluates the influence of chitosan and hydroxyapatite components, substrate roughness, stability, as well as surface porosity produced by enzymatic hydrolysis to cell adhesion and proliferation. L929 mouse fibroblastic lung cells were cultured on enzymatic degraded porous chitosan-hydroxyapatite hybrids. The presence of hydroxyapatite and porosity produced by partial lysozyme hydrolysis enhance cell proliferation. Besides, cell adhesion and proliferation are primarily dependent on substrate roughness and stability.
Characterization of Protamine as a Transfection Accelerator for Gene Delivery
Authors: Tsuchiya Yuri , Ishii Tsuyoshi , Okahata Yoshio , Sato Toshinori
Published: October 2006

Protamine is an FDA-approved compound with a documented safety profile that facilitates efficient plasmid condensation for gene delivery by various types of cationic liposomes. It also improves adenoviral vector-mediated gene transfer as a transfection accelerator. However, there is no consensus as to the mechanism of protamine on gene delivery into cells. To analyze the uptake and subcellular distribution, plasmid and protamine were labeled with FITC and Texas-Red, respectively. Although the uptake of FITC-labeled plasmid/protamine complexes into the cells was the same as that of free FITC-labeled plasmid in HeLa, SOJ and A549 cells, they improved the transfection efficiency by several orders of magnitude. Moreover, we found that protamine derived from different sources (salmon, herring and trout sperm) had different transfection efficiencies; however, the gene transfer efficiency with protamine was lower than with optimized poly(L-lysine) and DEAE-Dextran. There were likely two main reasons: firstly, the uptake of plasmid mediated by protamine was complete within the first 10min because the particle size increased as time passed, and secondly, the plasmid/protamine complexes were not released from endosomal membrane. These results indicate that as a transfection accelerator from an appropriate protamine source, with controlled particle size and facile release from endosomes would lead to successful gene delivery with protamine.
Liposome Immobilization on Cross-linked Polymer Gel by In Situ Formation of Cleavable Covalent Bonds
Authors: Khaleque MD. Abdul , Okumura Y. , Mitani M.
Published: October 2006

Immobilization of liposomes onto chemically modified Sephacryl gel particles by in situreaction between liposome-incorporated thiols and mercapto moieties on the gel to form disulfide linkages was investigated. For the immobilization, both the mercapto moieties and the incorporated thiol were essential. The immobilization occurred upon coincubation of the modified liposomes with the modified gel for 48 hours. Once immobilized, no spontaneous detachment of the immobilized liposomes was observed. The degree of immobilization depended on both the thiol content and the ratio of the liposomes to the gel partilces. In a typical immobilization with 25mol% 1-octanethiol, 82% of the liposomal phosphatidylcholine in the system was found to be associated with the gel. By decreasing the ratio of the liposomes to gel it was possible to bring the immobilization close to quantitative one. Among the three different thiols examined (1-octanethiol, 1-hexadecanethiol and thiocholesterol), the extent of the immobilization was slightly higher with thiocholesterol than the alkanethiols. The immobilized liposomes were detached from the gel with dithiothreitol. Approximately 60% of the fluorescent dextran derivative encapsulated in the liposomes was retained throughout the immobilization-detachment process. The gel left after the detachment remained active for immobilizing a fresh batch of thiol-liposomes.