bluuebunny/crossref_metadata_2025 huggingface dataset:
Early Cretaceous bivalves of the Neuquén Basin, west‐central Argentina: notes on taxonomy, palaeobiogeography and palaeoecology
Authors: Lazo Dario G.
Published: March 2007

This paper provides an updated taxonomic inventory of the bivalve fauna collected in the Pilmatué Member of the Agrio Formation of the Neuquén Basin, west‐central Argentina, places the fauna in its palaeobiogeographic setting, and addresses its palaeoecological significance. Thirty‐one Late Valanginian to Early Hauterivian bivalve species within 24 genera were identified. A large part (32%) of the identified bivalve species occur over a wide geographical area: from the Pacific coast of South America to Europe, North Africa, Central Asia and East and South Africa; some are also recorded in Japan. A relatively high degree of endemism (26%) is shown, suggesting that some of the bivalve species had barriers to their dispersal; larval strategy and length of larval development were probably important. A significant number (42%) of the bivalve taxa are left in open nomenclature as they are probably new species. Bivalve guilds are described to interpret palaeoecology, in particular the ecospace utilization. Guilds are based on tiering, life habit, and feeding category. Eight guilds are recognized: free‐lying epifaunal, cemented epifaunal, epibyssate, boring, endobyssate, shallow burrowing, deep burrowing and deep burrowing with symbiotic bacteria. The fauna is composed only of suspension‐feeders indicating that food resources were dominantly in suspension, in agreement with the predominantly shallow‐water aspect of the study deposits. The ecospace utilization in the shoreface is broader than in the offshore shelf, suggesting more favourable living conditions and/or a wider range of different habitat types represented. Copyright © 2007 John Wiley & Sons, Ltd.
Apolipoprotein E deficiency enhances the antigen‐presenting capacity of Schwann cells
Authors: Duan Rui‐Sheng , Jin Tao , Yang Xin , Mix Eilhard , Adem Abdu , Zhu Jie
Published: March 2007

Apolipoprotein E (apoE) has immunomodulatory properties and has been implicated in the pathogenic mechanism of autoimmune diseases. Previously, the authors found that apoE deficiency increased the susceptibility to experimental autoimmune neuritis (EAN), an animal model for human Guillain‐Barré syndrome. To further elucidate the mechanism behind apoE deficiency exacerbating EAN, the authors investigated the role of major target and important antigen‐presenting cells of the peripheral nerve system, Schwann cells (SCs), in apoE knockout mice. Treatment of apoE deficient SCs with recombinant mouse interferon‐γ and lipopolysaccharide resulted in higher MHC‐II and CD40 expression as compared with normal SCs derived from wild‐type mice. The increased MHC‐II and CD40 expression on SCs was accompanied by lower levels of intracellular IL‐6 production within SCs of apoE deficiency, which is confirmed by the neutralization with anti IL‐6 antibody. The increased antigen‐presenting capacity of apoE deficient SCs was further explored by enhancement of T cell proliferation co‐cultured with P0 peptide 180–199 specific T cells derived from EAN mice immunized with the P0 peptide. In conclusion, apoE may protect mice from EAN and probably also from chronic inflammatory demyelinating polyneuropathy by affecting the antigen‐presenting function of SCs via influence of IL‐6 production. © 2007 Wiley‐Liss, Inc.
Hypoosmotic swelling and ammonia increase oxidative stress by NADPH oxidase in cultured astrocytes and vital brain slices
Authors: Reinehr Roland , Görg Boris , Becker Stephan , Qvartskhava Natalia , Bidmon Hans J. , Selbach Oliver , Haas Helmut L. , Schliess Freimut , Häussinger Dieter
Published: March 2007

The role of NADPH oxidase (NOX) and the regulatory subunit p47phox for hypoosmotic ROS generation was studied in cultured rat astrocytes and brain slices of wilde type and p47phox knock‐out mice. Cultured rat astrocytes express mRNAs encoding for the regulatory subunit p47phox, NOX1, 2, and 4, and the dual oxidases (DUOX)1 and 2, but not NOX3. Hypoosmotic (205 mosmol/L) swelling of cultured astrocytes induced a rapid generation of ROS that was accompanied by serine phosphorylation of p47phox and prevented by the NADPH oxidase inhibitor apocynin. Apocynin also impaired the hypoosmotic tyrosine phosphorylation of Src. Both, hypoosmotic ROS generation and p47phox serine phosphorylation were sensitive to the acidic sphingomyelinase inhibitors AY9944 and desipramine, the protein kinase C (PKC)ζ‐inhibitory pseudosubstrate peptide, the NMDA receptor antagonist MK‐801 and the intracellular Ca2+ chelator BAPTA‐AM. Also hypoosmotic exposure of wilde type mouse cortical brain slices increased ROS generation, which was allocated in part to the astrocytes and which was absent in presence of apocynin and in cortical brain slices from p47phox knock‐out mice. Also ammonia induced a rapid ROS production in cultured astrocytes and brain slices, which was sensitive to apocynin. The data suggest that astrocyte swelling triggers a p47phox‐dependent NADPH oxidase‐catalyzed ROS production. The findings further support a close interrelation between osmotic and oxidative stress in astrocytes, which may be relevant to different brain pathologies including hepatic encephalopathy. © 2007 Wiley‐Liss, Inc.
A review of the therapeutic agents used in the management of polycythaemia vera
Authors: McMullin Mary Frances
Published: March 2007

The acquired clonal disorder Polycythaemia Vera leads to increased erythropoiesis, myelopoiesis and megakaryopoeisis. These anomalies result in an increased incidence of thromboembolic events, transformation to acute leukaemia and myelofibrosis. Treatments which aim to reduce the event rate may increase anaemia but may also affect the rate of complications. This paper reviews the evidence for the treatments which have been used in the management of the disorders over a 50 plus year period. Assessment of this evidence and its limitations form the basis for the current suggested management plans. Copyright © 2007 John Wiley & Sons, Ltd.
China's new law on enterprise bankruptcy: a story with a happy end?
Authors: Falke Mike
Published: March 2007

The Chinese National People's Congress has recently promulgated a new law on enterprise bankruptcy, which will come into force in June 2007. For the first time, the law intends to cover generally both private and state‐owned enterprises (SOEs). The law does widely comply with accepted international standards and provisions found in modern insolvency codes of other jurisdictions. However, it also contains several gaps, blurred provisions and legislative shortcomings, which have to be addressed promptly in order to assure a smooth implementation of the new law. Copyright © 2007 John Wiley & Sons, Ltd.
Identification of overexpressed genes in hepatocellular carcinoma, with special reference to ubiquitin‐conjugating enzyme E2C gene expression
Authors: Ieta Keisuke , Ojima Eiki , Tanaka Fumiaki , Nakamura Yoshito , Haraguchi Naotsugu , Mimori Koshi , Inoue Hiroshi , Kuwano Hiroyuki , Mori Masaki
Published: March 2007

This study consisted of 2 aims: (i) to determine genes associated with hepatocellular carcinoma (HCC) by microarray analysis; and (ii) to evaluate the clinicopathological significance of human ubiquitin‐conjugating enzyme E2C (Ube2c) found to be overexpressed in HCC from microarray analysis. Laser microdissection and cDNA‐microarray were performed to identify genes associated with HCC. We then focused on the Ube2c gene. Using real‐time quantitative reverse transcription‐polymerase chain reaction (RT‐PCR), Ube2c expression status and clinicopathological significance were studied in 65 clinical HCC samples. A number of genes upregulated in HCC cells compared to noncancerous liver cells were identified, one of which was the Ube2c gene. Ube2c gene expression in the cancer tissue was higher than in the corresponding noncancerous tissue in 62 of the 65 cases (95.4%, p < 0.01). Tumors with high Ube2c expression showed higher frequencies of tumor invasion to capsular formation (fc‐inf), invasion to portal vein (vp) and tumor de‐differentiation (p < 0.05). Patients with high Ube2c expression also showed significantly worse disease‐free survival rates than those with low Ube2c expression (p < 0.01). In addition, Ube2c expression was found to be an independent prognostic factor for disease‐free survival rate in multivariate analysis. We identified differentially expressed genes between HCC and normal liver tissues. Of those, the Ube2c gene appeared to be associated with HCC progression, and may be useful as a prognostic indicator for HCC patients. © 2007 Wiley‐Liss, Inc.
Risk of high‐grade cervical intra‐epithelial neoplasia based on cytology and high‐risk HPV testing at baseline and at 6‐months
Authors: Bulk Saskia , Bulkmans Nicole W.J. , Berkhof Johannes , Rozendaal Lawrence , P. Boeke A. Joan , Verheijen René H.M. , Snijders Peter J.F. , Meijer Chris J.L.M.
Published: March 2007

Adding a test for high‐risk human papillomavirus (hrHPV) to cytological screening enhances the detection of high‐grade cervical intraepithelial neoplasia (≥CIN2), but data are required that enable long‐term evaluation of screening. We investigated the ≥CIN2 risk for women participating in population‐based screening as a function of hrHPV and cytology testing results at baseline and at 6 months. We included 2,193 women aged 30–60 years participating in a population‐based screening trial who received colposcopy or a repeat testing advice at baseline. The main endpoint was histologically confirmed ≥CIN2 diagnosed within 36 months. hrHPV testing was more sensitive than cytology for ≥CIN2 (relative sensitivity 1.4, 95%CI: 1.3–1.5; absolute sensitivity 94.1 and 68.0%, respectively). The 18‐month ≥CIN2 risks in women with a hrHPV‐positive smear and in women with abnormal cytology were similar (relative risk 0.9, 95%CI: 0.8–1.1). Women with HPV16 and/or HPV18 had a higher ≥CIN2 risk than other hrHPV‐positive women irrespective of the cytological grade. Repeat testing showed that both cytological regression and viral clearance were strongly associated with a decrease in ≥CIN2 risk. Notably, women who had a double negative repeat test at 6 months had a ≥CIN2 risk of only 0.2% (95%CI: 0.0–1.1) and hrHPV‐negative women with baseline borderline or mild dyskaryosis and normal cytology at 6 months had a ≥CIN2 risk of 0% (95%CI: 0.0–0.8). Using hrHPV and/or cytology testing, risk of ≥CIN2 can be assessed more accurately by repeat testing than single visit testing. Hence, when hrHPV testing is implemented, patient management with repeat testing is a promising strategy to control the number of referrals for colposcopy. © 2007 Wiley‐Liss, Inc.
Treatment of implanted mammary tumors with recombinant vesicular stomatitis virus targeted to Her2/neu
Authors: Bergman Ira , Griffin Judith A. , Gao Yanhua , Whitaker‐Dowling Patricia
Published: March 2007

Vesicular stomatitis virus (VSV) is being developed for cancer therapy. We have created a recombinant replicating VSV (rrVSV) that targeted to Her2/neu expressing breast cancer cells and expresses mouse GM‐CSF. We now tested the efficacy of this rrVSV in the treatment of peritoneal tumor implants of D2F2/E2 cells, a BALB/c mouse mammary tumor cell line, which was stably transfected to express Her2/neu. Mice were treated 1 day following tumor implantation with either 2 × 108 infectious doses rrVSV or conditioned media (CM). All control animals developed massive peritoneal tumor with a median survival of 16 days. Nine of 10 rrVSV treated mice survived long term with no evidence of tumor. rrVSV had much less efficacy in treating implants of the parent D2F2 cells that did not express Her2/neu. The median survival was 13.5 days in mice treated with CM and 21 days in those treated with rrVSV. There was one long term survivor in the rrVSV treated group. None of the rrVSV treated animals showed evidence of viral toxicity. Three of 7 long term survivors did not develop tumor when rechallenged first with D2F2/E2 and then with D2F2 cells. Both successful therapy and resistance to rechallenge were T‐cell dependent. These studies demonstrate that targeted rrVSV eliminated peritoneal implants of Her2/neu expressing tumor and elicited an anti‐tumor T‐cell immunologic response. © 2007 Wiley‐Liss, Inc.
Erionite and asbestos differently cause transformation of human mesothelial cells
Authors: Bertino P. , Marconi A. , Palumbo L. , Bruni B. M. , Barbone D. , Germano S. , Dogan A.U. , Tassi G. F. , Porta C. , Mutti L. , Gaudino G.
Published: March 2007

Malignant mesothelioma (MM) is an aggressive tumor associated with environmental or occupational exposure to asbestos fibers. Erionite is a fibrous zeolite, morphologically similar to asbestos and it is assumed to be even more carcinogenic. Onset and progression of MM has been suggested as the result of the cooperation between asbestos and other cofactors, such as SV40 virus infection. Nevertheless, several cases of MM were associated with environmental exposure to erionite in Turkey, where SV40 was never isolated in MM specimens. We show here that erionite is poorly cytotoxic, induces proliferating signals and high growth rate in human mesothelial cells (HMC). Long term exposure to erionite, but not to asbestos fibers, transforms HMC in vitro, regardless of the presence of SV40 sequences, leading to foci formation in cultured monolayers. Cells derived from foci display constitutive activation of Akt, NF‐κB and Erk1/2, show prolonged survival and a deregulated cell cycle, involving cyclin D1 and E overexpression. Our results reveal that erionite is able per se to turn HMC into transformed highly proliferating cells and disclose the carcinogenic properties of erionite, prompting for a careful evaluation of environmental exposure to these fibers. The genetic predisposition to the effect of erionite is a separate subject for investigation. © 2007 Wiley‐Liss, Inc.
Sectoral adjustment of employment to shifts in outsourcing and trade: evidence from a dynamic fixed effects multinomial logit model
Authors: Egger Peter , Pfaffermayr Michael , Weber Andrea
Published: March 2007

This paper analyzes the effects of trade and outsourcing on the transition probabilities of employment between sectors, using a dynamic multinomial logit framework with fixed effects. The data cover a sample of individual Austrian male workers over the period 1988–2001. Our results strongly support the view that international economic forces are important determinants of labor market turnover. In particular, an increase in the outsourcing intensity negatively affects the probability of staying in or changing into the manufacturing sector, even more so for industries with a comparative disadvantage. Copyright © 2007 John Wiley & Sons, Ltd.
Money demand function estimation by nonlinear cointegration
Authors: Bae Youngsoo , de Jong Robert M.
Published: March 2007

Conventionally, the money demand function is estimated using a regression of the logarithm of money demand on either the interest rate or the logarithm of the interest rate. This equation is presumed to be a cointegrating regression. In this paper, we aim to combine the logarithmic specification, which models the liquidity trap better than a linear model, with the assumption that the interest rate itself is an integrated process. The proposed technique is robust to serial correlation in the errors. For the USA, our new technique results in larger coefficient estimates than previous research suggested, and produces superior out‐of‐sample prediction. Copyright © 2007 John Wiley & Sons, Ltd.
Assessing the performance of matching algorithms when selection into treatment is strong
Authors: Augurzky Boris , Kluve Jochen
Published: March 2007

This paper investigates the method of matching regarding two crucial implementation choices: the distance measure and the type of algorithm. We implement optimal full matching—a fully efficient algorithm—and present a framework for statistical inference. The implementation uses data from the NLSY79 to study the effect of college education on earnings. We find that decisions regarding the matching algorithm depend on the structure of the data: In the case of strong selection into treatment and treatment effect heterogeneity a full matching seems preferable. If heterogeneity is weak, pair matching suffices. Copyright © 2007 John Wiley & Sons, Ltd.
Codependence in cointegrated autoregressive models
Authors: Schleicher Christoph
Published: March 2007

This paper investigates codependent cycles, i.e., transitory components that react to common stimuli in a similar, although not necessarily synchronous fashion. Unlike previous studies, the methodology of this paper allows FIML estimation of the restricted VAR/VECM and therefore the extraction of the unobserved codependent cyclical components via a Beveridge‐Nelson decomposition. It is further shown that the number and order of cofeature combinations that yield the scalar component models associated with codependence is limited by the dimension of a finite‐order VAR system. Monte Carlo simulations indicate that LR tests based on FIML estimates have higher power than alternative GMM and canonical correlations tests, while maintaining good size properties. An empirical application investigates the presence of codependence in UK consumption data. Copyright © 2007 John Wiley & Sons, Ltd.
Transitional CpG methylation between promoters and retroelements of tissue‐specific genes during human mesenchymal cell differentiation
Authors: Kang Moo‐Il , Kim Hye‐Soo , Jung Yu‐Chae , Kim Young‐Ho , Hong Seung‐Jin , Kim Mi‐Kyoung , Baek Ki‐Hyun , Kim Chun–Choo , Rhyu Mun‐Gan
Published: March 2007

In general, methylation of the promoter regions is inversely correlated with gene expression. The transitional CpG area between the promoter‐associated CpG islands and the nearby retroelements is often methylated in a tissue‐specific manner. This study analyzed the relationship between gene expression and the methylation of the transitional CpGs in two human stromal cells derived from the bone marrow (BMSC) and adipose tissue (ATSC), both of which have a multilineage differentiation potential. The transitional CpGs of the osteoblast‐specific (RUNX2 and BGLAP), adipocyte‐specific (PPARγ2), housekeeping (CDKN2A and MLH1), and mesenchyme‐unrelated (RUNX3) genes were examined by methylation‐specific PCR. The expression of each gene was measured using reverse‐transcription PCR analysis. The RUNX2, BGLAP, and CDKN2A genes in the BMSC, and the PPARγ2 gene in the ATSC exhibited hypomethylation of the transitional CpGs along with the strong expression. The CpG island of RUNX3 gene not expressed in both BMSC and ATSC was hypermethylated. Transitional hypomethylation of the MLH1 gene was accompanied by the higher expression in the BMSC than in the ATSC. The weakly methylated CpGs of the PPARγ2 gene in the BMSC became hypomethylated along with the strong expression during the osteoblastic differentiation. There were no notable changes in the transitional methylation and expression of the genes other than PPARγ2 after the differentiation. Therefore, the transitional methylation and gene expression established in mesenchymal cells tend to be consistently preserved under the induction of differentiation. Weak transitional methylation of the PPARγ2 gene in the BMSC suggests a methylation‐dependent mechanism underlying the adiopogenesis of bone marrow. J. Cell. Biochem. 102: 224–239, 2007. © 2007 Wiley‐Liss, Inc.
Neutrophil‐activating protein‐2‐ and interleukin‐8‐mediated angiogenesis
Authors: Powell John A. , Mousa Shaker A.
Published: March 2007

In this study, we investigated the anti‐angiogenic potential of nitric oxide (NO) donors and anti‐integrin compounds against neutrophil‐activating protein‐2 (NAP‐2), interleukin‐8 (IL‐8), and basic fibroblast growth factor (FGF‐2)‐induced angiogenesis. In vivo, recombinant human NAP‐2 and FGF‐2 induce a potent and comparable angiogenic response in the chick embryo chorioallantoic membrane (CAM). We demonstrate that NO donors and anti‐integrin agents are capable of abrogating either NAP‐2‐ or FGF‐2‐induced angiogenesis in the CAM model. The NO donor, S‐nitroso N‐acetyl penicillamine (SNAP), blocked either NAP‐2‐ or FGF‐2‐mediated angiogenesis in the CAM. Similarly, angiogenesis stimulated with NAP‐2 or FGF‐2 was blocked by antagonist of the αvβ3 integrin in the CAM model. However, the inhibition of NAP‐2 and IL‐8 by the anti‐integrin compound is significantly less than the inhibition observed with FGF‐2 as the angiogenic stimulus. Similarly, the ability of these mechanisms to also inhibit endothelial cell differentiation was demonstrated. Taken together, these data illustrate the involvement of multiple pathways in the mechanisms of action for the α‐chemokine‐ and cytokine‐mediated angiogenesis. These approaches may be a useful tool for the inhibition of angiogenesis associated with human tumor growth or with neovascular, ocular, and inflammatory diseases where chemokines and cytokines are involved. J. Cell. Biochem. 102: 412–420, 2007. © 2007 Wiley‐Liss, Inc.
The role of the Cdk9/Cyclin T1 complex in T cell differentiation
Authors: Leucci Eleonora , De Falco Giulia , Onnis Anna , Cerino Giovanna , Cocco Mario , Luzzi Anna , Crupi Domenica , Tigli Chiara , Bellan Cristiana , Tosi Piero , Leoncini Lorenzo , Giordano Antonio
Published: March 2007

The Cdk9/Cyclin T1 complex is very important in controlling specific differentiative pathways of several cell types, including muscle cells and neurons. We recently demonstrated the involvement of this complex in B cell activation/differentiation. To check whether the Cdk9/Cyclin T1 complex is also involved in the T cell activation/differentiation process, we isolated different T cell populations by magnetic separation, based on their surface antigens. We observed that the expression level of Cdk9/Cyclin T1 increases in effector T cells (CD27+), as well as in activated T cells (CD25+) and memory T cells (CD45RA−), thus suggesting a specific upregulation of the Cdk9/Cyclin T1 complex following antigen encounter. We have previously demonstrated that in B cells, Cdk9 interacts in vivo with the E2A gene products E12/E47 (members of the basic helix‐loop‐helix family) which are involved in differentiation. In this article, we show that this interaction also occurs in T cells. This suggests an active role for the Cdk9/Cyclin T1 complex during lymphoid differentiation, through physical binding with E12 and E47. These preliminary results suggest that the Cdk9/Cyclin T1 complex may be important in the activation and differentiation program of lymphoid cells and that its upregulation, which is due to still unknown mechanisms, may contribute to malignant transformation. J. Cell. Physiol. 212: 411–415, 2007. © 2007 Wiley‐Liss, Inc.
Antenatal diagnosis of double outlet of right ventricle without extracardiac anomaly: A report of 4 cases
Authors: Tongsong Theera , Chanprapaph Pharuhas , Sittiwangkul Rekwan , Khunamornpong Surapan
Published: March 2007

Four fetuses were diagnosed antenatally with double outlet of right ventricle (DORV) at 17, 20, 26, and 28 weeks' gestation, respectively, using 2‐dimensional sonography. Chromosome study was normal in all 4 cases, and there were no extracardiac abnormalities. The sonographic diagnoses were based on the following findings: (1) arising of the 2 great vessels predominantly from the right ventricle; (2) the presence of bilateral coni; and (3) parallel direction of the 2 vessels rather than the normal perpendicular course. Two cases were terminated electively with postnatal autopsy confirmation; the other 2 cases were closely monitored throughout pregnancy and underwent normal vaginal delivery at term and subsequent surgical correction with good outcome. In conclusion, DORV can be readily diagnosed in utero by checking outflow tract even without 3‐dimensional sonography and in the absence of obvious risk for congenital heart defects. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Large mycotic aneurysm of the peroneal artery
Authors: Albayrak Ramazan , Saglam Hayrettin , Emmıler Mustafa , Degırmencı Bumin , Sahın Onder
Published: March 2007

We describe the case of a 37‐year‐old patient with mycotic aneurysm of the right peroneal artery associated with episodes of endocarditis. There are only 7 cases of mycotic aneurysms of the crural arteries reported in the literature. To the best of our knowledge, this is the first reported case of a mycotic aneurysm of the peroneal artery in an adult. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007.
Diffuse leukoencephalopathy: Unusual sonographic finding in an infant with mitochondrial disease
Authors: Hung Po‐Cheng , Wang Huei‐Shyong
Published: March 2007

Several mitochondrial diseases are known to occasionally involve the cerebral white matter, but in these cases the major findings are involved in the basal ganglia and brainstem. We report a case of diffuse white matter involvement in an infant with mitochondrial disease that was diagnosed via mitochondrial DNA analysis. Mitochondrial disease should be considered in the diagnosis of diffuse leukoencephalopathy in infancy. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007
Synthesis and in vivo evaluation in mice of [123I]‐(4‐fluorophenyl)[1‐(3‐iodophenethyl)piperidin‐4‐yl]methanone as a potential SPECT‐tracer for the serotonin 5‐HT2A receptor
Authors: Blanckaert P. , Burvenich I. , Devos F. , Slegers G.
Published: March 2007

This work reports the synthesis, radiolabelling and in vivo evaluation in NMRI mice of [123I]‐(4‐fluorophenyl)[1‐(3‐iodophenethyl)piperidin‐4‐yl]methanone ([123I]‐3‐I‐CO) as a potential SPECT tracer for the 5‐HT2A receptor. The tributylstannylprecursor was synthesized with a 15% overall yield. Radiolabelling was performed using an electrophilic iododestannylation with yields of 85%. Radiochemical purity was always >95%. Log P was determined to be 3.10±0.10. The tracer showed good uptake in mouse brain (6.3±1.3% ID/g tissue at 10 min p.i., 2±0.36% ID/g tissue at 1 h p.i.). These results warrant further research in larger animals to determine suitability of [123I]‐3‐I‐CO as a 5‐HT2A tracer. Copyright © 2007 John Wiley & Sons, Ltd.
Expedient synthesis of deuterium‐labelled amides within micro‐reactors
Authors: Hooper Julian , Watts Paul
Published: March 2007

The pharmaceutical industry relies heavily on the synthesis of small quantities (10–500 mg) of stable, isotopically labelled compounds in the evaluation of new drug candidates for metabolism studies. As a result of the phenomenal cost of labelled materials even the preparation of small quantities can be extremely expensive.

In this paper, for the first time, we report that micro‐reactor technology may be used to prepare stable deuterium‐labelled compounds by conducting all optimization experiments using unlabelled precursors and simply substituting the labelled derivatives once the optimization is complete. Here, we wish to present a simple, general procedure for the synthesis of amides containing isotopic labels demonstrated using [C‐2H3]acetyl chloride 1. The reaction is carried out within a micro‐reactor set‐up which we believe offers superiority over other reported methods viz requiring stoichiometric quantities of reagents, high containment of the system and generality of the technique, obtaining products in high yields. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and deuterium labelling of the pure selective estrogen receptor modulator (SERM) acolbifene glucuronides
Authors: Sancéau Jean‐Yves , Larouche Denis , Caron Brigitte , Bélanger Patrick , Coquet Agnès , Bélanger Alain , Labrie Fernand , Gauthier Sylvain
Published: March 2007

Acolbifene (EM‐652·HCl, SCH 57068·HCl), a highly potent and orally active selective estrogen receptor modulator (SERM), is at late stage clinical development for the treatment of estrogen‐sensitive breast cancer. Acolbifene‐7‐glucuronide 1 (major) and acolbifene‐4′‐glucuronide 2 (minor) were identified as metabolites of acolbifene in the human. The two monoglucuronides and a diglucuronide 3 as well as the corresponding 2H‐labelled derivatives 4–6 were synthesised for use as preclinical and clinical standards for LC–MS/MS analysis. All glucuronides were prepared by the Schmidt glycosylation of monoprotected acolbifene with a glucuronyl imidate at −10°C to prevent epimerisation at the C‐2 position. The two monoglucuronides 1 and 2 of acolbifene were separated by semi‐preparative HPLC. Incorporation of three deuteriums was achieved by alkylation of chromanone 15 with C2H3MgI followed by dehydration with C2H3CO2 2H/2H2O. After chemical resolution and salt neutralisation, [2H3]acolbifene 19 was obtained with 99.4% enantiomeric purity and >98% isotopic purity. Copyright © 2007 John Wiley & Sons, Ltd.
Relaxation and susceptibility MRI characteristics in Hallervorden‐Spatz syndrome
Authors: Vinod Desai Sunali , Bindu Parayil Shankaran , Ravishankar Shivasankar , Jayakumar Peruvumba Narayan , Pal Pramod Kumar
Published: March 2007

Purpose

To evaluate the imaging characteristics of the brain with respect to relaxation and susceptibility in Hallervorden‐Spatz syndrome (HSS), a rare inherited neurodegenerative disorder (also referred to as neurodegeneration with brain iron accumulation).

Materials and Methods

We reviewed 13 affected individuals who satisfied the inclusion criteria for HSS. Clinically, the patients were divided into two groups: early‐childhood onset (age of onset before 10 years) and late‐childhood onset (age of onset after 10 years). MRI was performed on 1.5T MR equipment. The imaging protocol included spin‐echo (SE) T1‐weighted (T1W), turbo spin‐echo (TSE) T2W, and fluid attenuated inversion recovery (FLAIR) sequences in all patients. Susceptibility‐weighted imaging (SWI) included a fast low‐angle shot (FLASH) sequence in 10 patients and a blood oxygen level‐dependent (BOLD) sequence in two patients.

Results

All of the patients showed hyperintensity on T1WI and hypointensity on T2WI in the globus pallidi (GPs) bilaterally. Central or anteromedial hyperintensity was found in all but one patient. FLASH showed augmented hypointensity in 10 patients, and BOLD showed bilateral striatonigral abnormal pigmentation in two patients. MR spectroscopy (MRS) showed normal spectra in four patients, and a reduced NAA/Cho ratio in two.

Conclusion

MRI showed prominent signal abnormalities in the GP bilaterally in HSS. T1WI showed hyperintensity in all cases of HSS in addition to the “eye‐of‐the‐tiger” sign on T2WI. SWI, FLASH, and BOLD demonstrated mineral deposition in the GP better than conventional imaging. Involvement of the striatonigral pathways was demonstrated for the first time on BOLD SWI. J. Magn. Reson. Imaging 2007. © 2007 Wiley‐Liss, Inc.
Comparing the MESFET and HEMT models for efficient circuit design
Authors: Touhami R. , Yagoub M. C. E. , Baudrand H.
Published: March 2007

In this paper, the relative advantages of several widely used MESFET and HEMT models have been compared. The nonlinear behaviours of the Curtice quadratic, Curtice cubic, Statz, Materka, Rodriguez, and Chalmers models were investigated through their current–voltage–temperature characteristics. To better fit such characteristics, neural‐based models of MESFET and HEMT were generated using a Levenberg–Marquardt back‐propagation algorithm. Close agreement was observed between simulated results and experimental data. Copyright © 2007 John Wiley & Sons, Ltd.
Raman scattering as a probe of intermediate phases in glassy networks
Authors: Boolchand P. , Jin Mingji , Novita D. I. , Chakravarty S.
Published: March 2007

Bulk glass formation occurs over a very small part of phase space, and ‘good’ glasses (which form even at low quench rates ∼10 K/sec) select an even smaller part of that accessible phase space. An axiomatic theory provides the physical basis of glass formation, and identifies these sweet spots of glass formation with existence of rigid but stress‐free networks for which experimental evidence is rapidly emerging. Recently, theory and experiment have come together to show that these sweet spots of glass formation occur over a range of chemical compositions identified as ‘intermediate phases’ (IPs). These ranges appear to be controlled by elements of local and medium‐range molecular structures that form isostatically rigid networks. IP glasses possess nonhysteretic glass transitions (Tg's) that do not age much. Raman scattering has played a pivotal role in elucidating the molecular structure of glasses in general, and in identifying domains of IPs. Experiments reveal that these phases possess sharp phase boundaries and are characterized by an optical elasticity that varies with network mean coordination number, r, as power law. In this review, we provide examples in chalcogenide and oxide glass systems in which these phases along with optical elasticity power laws have been established. IP glasses represent self‐organized nanostructured functional materials optimized by nature. Copyright © 2007 John Wiley & Sons, Ltd.
The European Nutrigenomics Organisation: linking genomics, nutrition and health research
Authors: Astley Siân B , Elliott Ruan M
Published: March 2007

The science of nutrigenomics allows us to consider not only the response of our genes, proteins and metabolism to diet but also life‐stage and lifestyle. Public health messages are failing to change people's behaviour and to counteract the flashy advertising promoting cheap nutritionally‐empty foods. Proponents suggest that using the information supplied by nutrigenomics to develop personalised diet and lifestyle regimens would enable consumers to make healthier choices for themselves. For some this will mean accessing new food products and genetic testing but for others it will mean better dietary advice that can be applied in their situation. Opponents argue that this approach merely panders to the worried‐wealthy‐well – those least in need of intervention because they are already diet and health conscious – and that nutrigenomics fails to address the real issues associated with diet‐related disease. Is nutrigenomics another over‐hyped science, which will ultimately disappoint, or is it an ideal tool for nutrition research? Copyright © 2007 Society of Chemical Industry
Parboiled rice: A study about attitude, consumer liking and consumption in São Paulo, Brazil
Authors: Behrens Jorge H , Heinemann Riana JB , Lanfer‐Marquez Ursula M
Published: March 2007

The consumption of parboiled rice in Brazil is low when compared to milled rice, despite alleged nutritional, convenience and technological benefits. Data collected through a survey with 186 consumers in the city of São Paulo, Brazil, were analysed with the aim of gaining a better understanding of local consumer attitudes towards parboiled rice. Six attitudinal items were assessed as giving a score on a five‐point Likert scale. Cluster analysis was used to identify three segments of respondents with different attitudinal patterns. Subsequently, correspondence analysis revealed associations among clusters and educational level and liking/consumption data. Most consumers did not show an established opinion about the main characteristics of parboiled which indicates a weakness of the product promotion. A positive attitude, as demonstrated by a higher intake of parboiled rice, was a reflection of habit and liking, while a negative attitude seemed to be due to previous negative experience and misconceptions about the product. Copyright © 2007 Society of Chemical Industry
Effect of calcium salts on the texture, structure and sensory acceptance of osmotically dehydrated guavas
Authors: Pereira Leila M , Carmello‐Guerreiro Sandra M , Bolini Helena MA , Cunha Rosiane L , Hubinger Miriam D
Published: March 2007

The effect of additives, calcium chloride and calcium lactate (5–25 g kg−1), on the osmotic dehydration of guavas with sucrose solutions was studied, aiming at the structural preservation of processed fruits. The osmotic process was evaluated from the reduction in weight of the guavas, water loss and solids gain, and the samples were analyzed with respect to calcium content, texture (stress and strain at failure, relaxation time and residual stress), structure by light microscopy and sensory acceptance. Calcium salts had a strong influence on the texture and structure of the processed guavas, resulting in the maintenance of tissue structure when calcium lactate was used at concentrations up to 15 g kg−1, and calcium chloride was used at 5 g kg−1. The sensory acceptability of guava was related to the structural and texture results. Calcium treatments did not improve guava's sensory acceptance. Guavas treated with calcium lactate showed good sensory acceptance, presenting slight inferior scores only at concentrations above 20g kg−1, while CaCl2 treated guavas showed average scores statistically equal to the sucrose and calcium lactate treated fruits only at 5 g kg−1. Copyright © 2007 Society of Chemical Industry
Hyperbranched Polyesters with Carboxylic or Sulfonic Acid Functional Groups for Crystallization Modification of Calcium Carbonate
Authors: Meng Qingwei , Chen Dongzhong , Yue Liwan , Fang Jianglin , Zhao Hui , Wang Lili
Published: March 2007

Hyperbranched aliphatic polyesters functionalized with carboxylic or sulfonic acid groups have been synthesized and employed as crystallization modifiers for calcium carbonate. The functionalized polyesters exhibit remarkable polymorph selectivity and morphology control. Stable spherical vaterite particles of diameter less than 10 µm with narrow size distribution were easy to produce on a large scale. With an increase in the concentration and monomer/core ratio of the polyester, the vaterite content increases accordingly with promoted morphology control to monodisperse spheres. The CaCO3 concentration and the initial pH can also influence the morphology and polymorphism of the produced calcium carbonate. Under certain conditions, well‐defined core‐shell structured vaterite spheres are obtained with obvious radial organization by nano‐aggregation of about 70 ± 10 nm crystallites, which may mediate and combine the nano‐aggregation and crystal growth formation mechanism of vaterite polymorph.

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Monomers for Adhesive Polymers, 7a
Authors: Moszner Norbert , Pavlinec Juraj , Angermann Jörg
Published: March 2007

Homopolymerization and copolymerization of N‐(2‐hydroxyethylmethyl)acrylamide (1) with N,N′‐diethyl‐1,3‐bis(acrylamido)propane (2) have been studied in ethanol/water solvents or in bulk. The polymerization rate exponent depends on the polymerization temperature and increased from 0.99 at 50 °C to 1.21 at 75 °C. The initial polymerization rate dependence on temperature between 50 and 75 °C in Arrhenius coordinates was linear. However, the slope increased with an increase in monomer concentration. The overall activation energy Ea varied from 64 kJ · mol−1 at 0.5 mol · L−1 to 76 kJ · mol−1 at 2.0 mol · L−1 monomer concentration. In addition, the reaction order with respect to the initiator AIBN deviated from the standard free radical polymerization kinetics. The exponent 0.42 indicated a significant participation of primary radicals in termination reactions. The polymerization reaction order declined from ideality as well, and the Ea and polymerization enthalpy changed with the batch composition variation, which could be explained through monomer/monomer, monomer/solvent, or monomer/polymer complexation. The chain transfer to polymer was considered as an origin for the polymer network formation in monomer 1 homopolymerization if its concentration in the batch was 1 mol · L−1 or higher. The more intensive polymerization acceleration with the monomer dilution and the greater heat released reduction with decrease in the monomer 1 to 2 ratios were evidenced in copolymerization. Nevertheless, the deviations from conventional reaction kinetics were not as pronounced as with acrylic or methacrylic acid polymerizations.

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Synthesis of Hydroxyl‐Terminated Poly(vinylcarbazole‐ran‐styrene) Copolymers by Nitroxide‐Mediated Polymerization
Authors: Morton Kaylyn , Graffe Andres , Marić Milan
Published: March 2007

A series of poly(vinylcarbazole‐ran‐styrene) copolymers with terminal hydroxyl groups were synthesized using nitroxide mediated polymerization (NMP) with the hydroxyl‐functional initiator VA‐086 and TEMPO as the mediator at 130 °C. Polymerizations were studied as a function of vinylcarbazole feed content, target molecular weight, and VA‐086/TEMPO ratio. The characterization of the copolymers was done by GPC and NMR. For feed concentrations of 40 mol‐% vinylcarbazole, copolymers with vinylcarbazole concentration up to 33 mol‐% could be obtained with narrow molecular weight distributions (PDI = 1.35) and exhibit pseudo‐“living” character up to conversions of about 20% if the target molecular weight was >100 kg · mol−1. 1H NMR indicated that the hydroxyl group was retained sufficiently with a functionality typically of about 0.7 hydroxyl groups per chain. Copolymers synthesized with higher vinylcarbazole feed content exhibited slower kinetics and were less controlled, resulting in much broader molecular weight distributions. The absence of control could be attributed to the absence of thermal initiation by vinylcarbazole which is advantageous toward controlling the radical concentration during the polymerization.

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Macromol. Chem. Phys. 5/2007
Authors: Meng Qingwei , Chen Dongzhong , Yue Liwan , Fang Jianglin , Zhao Hui , Wang Lili
Published: March 2007

Cover: The cover shows a SEM image of core/shell spherical vaterite particles produced in the presence of the schematically drawn hyperbranched polyesters with carboxylic acid functional groups. Further details can be found in the Full Paper by Q. Meng, D. Chen,* L. Yue, J. Fang, H. Zhao, and L. Wang on page 474.
A cross‐national study of the individual and national–cultural nomological network of consumer involvement
Authors: Broderick Amanda J.
Published: March 2007

The article theoretically proposes and empirically tests an individual and national–cultural nomological network of consumer involvement. A consumer survey in the United Kingdom, France, Germany, Spain, and Italy captures nomological network data. Findings are significant in three areas. First, the empirical study provides evidence for the cultural invariance of the measurement of consumer involvement. Second, results determine the mediating nature of individual‐level consumer involvement. The nomological network differentiates between the antecedent role of cognitive involvement and the subsequent affective involvement state with explanatory effect on brand commitment and brand experimentation. Third, the study identifies the moderating role that uncertainty avoidance and masculinity/femininity play on the involvement relationships. The article concludes by discussing the theoretical implications for the impact of individual and national–cultural variables on the activation and sources of consumer involvement. © 2007 Wiley Periodicals, Inc.
The Cutthroat Competition Between Termination and Transfer to Shape the Kinetics of Radical Polymerization
Authors: Smith Gregory B. , Russell Gregory T.
Published: March 2007

There is a fascinating interplay between termination and transfer that shapes the kinetics of radical polymerization (RP). In one limit all dead‐chain formation is by termination, in the other by transfer. Because of chain‐length‐dependent termination (CLDT), the rate law for RP takes a different form in each limit. However, common behavior is observed if one instead considers how the average termination rate coefficient varies with average degree of polymerization. Examples are given of using these principles to understand trends in actual RP data, and it is also demonstrated how to extract quantitative information on CLDT from simple steady‐state experiments.
The Importance of Chain‐Length Dependent Kinetics in Free‐Radical Polymerization: A Preliminary Guide
Authors: Heuts Johan P. A. , Russell Gregory T. , Smith Gregory B. , van Herk Alex M.
Published: March 2007

The effect of chain‐length dependent propagation at short chain lengths on the observed kinetics in low‐conversion free‐radical polymerization (frp) is investigated. It is shown that although the values of individual propagation rate coefficients quickly converge to the high chain length value (at chain lengths, i, of about 10), its effect on the average propagation rate coefficients, 〈kp〉, in conventional frp may be noticeable in systems with an average degree of polymerization (DPn) of up to 100. Furthermore it is shown that, unless the system is significantly retarded, the chain‐length dependence of the average termination rate coefficient, 〈kt〉, is not affected by the presence of chain‐length dependent propagation and that there exists a simple (fairly general) scaling law between 〈kt〉 and DPn. This latter scaling law is a good reflection of the dependence of the termination rate coefficient between two i‐meric radicals, k, on i. Although simple expressions seem to exist to describe the dependence of 〈kp〉 on DPn, the limited data available to date does not allow the generalization of these expressions.
Investigation of the Chain Length Dependence of kp: New Results Obtained with Homogeneous and Heterogeneous Polymerization
Authors: Schnöll‐Bitai Irene , Mader Christoph
Published: March 2007

New experimental results were collected for the free radical polymerization of styrene by pulsed laser polymerization in solution or in microemulsion. The location of the point of inflection (on the low molecular weight side) and the maximum of the first peak in the chromatograms (measured by size‐exclusion chromatography) was used to extract kp data. The extent of band broadening was determined with narrow polystyrene standards with an assumed Poisson chain length distribution. For a given experiment both kp values (obtained via the point of inflection and the maximum) were corrected and thus became identical in most cases. Even after the correction, the effect of chain length dependence persists to a higher chain length.
Studying the Fundamentals of Radical Polymerization Using ESR in Combination with Controlled Radical Polymerization Methods
Authors: Kajiwara Atsushi
Published: March 2007

Electron spin resonance (ESR) spectroscopy can contribute to understanding both the kinetics and mechanism of radical polymerizations. A series of oligo/poly(meth)acrylates were prepared by atom transfer radical polymerization (ATRP) and purified to provide well defined radical precursors. Model radicals, with given chain lengths, were generated by reaction of the terminal halogens with an organotin compound and the radicals were observed by ESR spectroscopy. This combination of ESR with ATRPs ability to prepare well defined radical precursors provided significant new information on the properties of radicals in radical polymerizations. ESR spectra of the model radicals generated from tert‐butyl methacrylate precursors, with various chain lengths, showed clear chain length dependent changes and a possibility of differentiating between the chain lengths of observed propagating radicals by ESR. The ESR spectrum of each dimeric, trimeric, tetrameric, and pentameric tert‐butyl acrylate model radicals, observed at various temperatures, provided clear experimental evidence of a 1,5‐hydrogen shift.