bluuebunny/crossref_metadata_2025 huggingface dataset:
New Oxadiazole Derivatives Showing partly Antiplatelet, Antithrombotic and Serotonin Antagonistic Properties
Authors: Bethge Katrin , Pertz Heinz H. , Rehse Klaus
Published: February 2005

Ten new 1, 2, 4‐oxadiazole‐ and six new 1, 3, 4‐oxadiazole‐carboxamides containing different lipophilic moieties (i.e. 4‐biphenyl‐, 1‐naphthyl, phenylpropyl‐ and n‐hexyl substituents) and additional basic groups which are mainly alkyl‐ and dialkylaminoalkyl residues have been synthesized and tested for antiplatelet effects in vitro (Born‐test) and antithrombotic properties in vivo (laser thrombosis model). If the platelet aggregation was induced by collagen, the inhibitory effects (IC50) were between 58 μM and 300 μM. Using serotonin (5‐HT) as an inducer, compound 6a (N‐(3‐dimethylaminopropyl‐5‐(biphenyl‐4‐yl)‐1, 3, 4‐oxadiazole‐2‐carboxamide) had an IC50 = 1 μM (12e: (N‐3‐Dimethylaminopropyl)‐3‐(1‐naphthyl)‐1, 2, 4‐oxadiazole‐5‐carboxamide, 6.7 μM). In an in vitro rat tail artery assay 6a and 12e behaved as a competitive 5‐HT2A receptor antagonist (6a: pKB = 6.86 ± 0.04; 12e: pKB = 6.66 ± 0.05). The antithrombotic effects of some compounds were small but significant (7–10 % inhibition of thrombus formation).
Evaluation of Some Pyrazoloquinolines as Inhibitors of Herpes Simplex Virus Type 1 Replication
Authors: Bekhit Adnan A. , El‐Sayed Ola A. , Aboul‐Enein Hassan Y. , Siddiqui Yunus M. , Al‐Ahdal Mohammed N.
Published: February 2005

Three structurally related aminopyrazoloquinoline derivatives were evaluated for their antiviral activity against Herpes Simplex virus type 1. These compounds were examined for their in vitro antiviral activity by two different bioassays, namely; crystal violet staining and tetrazolium dye (MTS) measurement. The antiviral role of these compounds was confirmed by enumerating the infectious particles with plaque assay. The acute toxicity values of the biologically active compounds were determined prior to their screening as antiviral agents.
FT‐IR spectrometry analysis of plasma fatty acyl moieties selective mobilization during endurance exercise
Authors: Petibois Cyril , Déléris Gérard
Published: February 2005

This study was designed to describe changes in plasma fatty acyl moieties during a 2‐h endurance exercise. Sixteen endurance‐trained subjects cycled 2 h at 55% of maximal power output and capillary blood was sampled every 15 min. Fourier‐transform infrared (FT‐IR) spectrometry was used to determine correlated changes between plasma fatty acyl moieties (FAM) structural characteristics and metabolic parameters (oxygen consumption, respiratory exchange ratio, glucose, lactate, TG, glycerol, and albumin). Opposite changes were found between carbohydrate and fatty acid metabolism during the second hour of exercise, i.e., a decrease of glucose and lactate concentrations while albumin, FAM, and TG increased. For fatty acid metabolism, FAM and TG did not showed the same pattern of changes at the end of exercise, i.e., TG remained constant after 90 min while FAM continued to increase. This late FAM concentration increase was correlated to the changes in albumin concentration and the ν CCH/νas CH3 and νas CH2/νas CH3 ratios. These ratios clearly showed that FAM unsaturation increased while chain length decreased. It was hypothesized that PUFA from TG adipose lipolysis ketone bodies (β‐hydroxybutyric acid) from liver may have been released in higher amounts as glycogen stores became depleted after 90 min of exercise. © 2005 Wiley Periodicals, Inc. Biopolymers 77: 345–353, 2005
Insights from ab initio quantum chemical calculations into the preferred tautomeric forms and binding affinities to CDK2 of substituted pyrazolopyridines
Authors: Duca José S. , Madison Vincent S.
Published: February 2005

Ab initio calculations were employed to compute pKa values and tautomer properties of a series of substituted pyrazolopyridines. The results show that the neutral 1H tautomer predominates, but upon protonation this proton migrates to give the preferred charged [2H,7H] tautomer. The basicity of the pyrazolopyridines is correlated with the electron donating capability of the 4‐substituent. Ab initio free energy calculations were also used to identify determinants of binding affinity for some recently published pyrazolopyridine inhibitors of CDK2. Hydrogen‐bonding affinity may be one important component of binding strength. © 2005 Wiley Periodicals Inc. Biopolymers (Pept Sci), 2005
Treatment of peritoneal dissemination from gastric cancer by peritonectomy and chemohyperthermic peritoneal perfusion
Authors: Yonemura Y , Kawamura T , Bandou E , Takahashi S , Sawa T , Matsuki N
Published: February 2005

Background

There is no standard treatment for peritoneal dissemination from gastric cancer. A novel treatment consisting of peritonectomy and intraoperative chemohyperthermic peritoneal perfusion (CHPP) was compared with conventional surgery and CHPP.

Methods

Records of all patients who underwent CHPP after cytoreductive surgery between 1992 and 2002 were reviewed.

Results

Data for 107 patients with peritoneal dissemination were available. Complete cytoreduction was achieved in 47 (43·9 per cent) of the 107 patients: 18 of 65 who underwent conventional surgery and 29 of 42 who had peritonectomy. Twenty-three patients (21·5 per cent) suffered from complications. The overall operative mortality rate was 2·8 per cent. Seventeen patients (15·9 per cent) were disease free and 87 subsequent deaths were related to disease progression. The median survival for all patients was 11·5 months, with a 5-year survival rate of 6·7 per cent. Median survival after complete cytoreduction was 15·5 months and that after incomplete cytoreduction was 7·9 months, with 5-year survival rates of 13 and 2 per cent respectively. Completeness of cytoreduction and peritonectomy were independent prognostic factors. The 5-year survival rate after complete cytoreduction by peritonectomy with CHPP was 27 per cent.

Conclusion

Complete cytoreduction after peritonectomy and CHPP may improve the survival of patients with peritoneal dissemination from gastric cancer.
Radioimmunotherapy and colorectal cancer
Authors: Koppe M J , Bleichrodt R P , Oyen W J G , Boerman O C
Published: February 2005

Background

Despite the success of radioimmunotherapy (RIT) using radiolabelled monoclonal antibodies (Mabs) directed against tumour-associated antigens in the treatment of non-Hodgkin's lymphoma, therapeutic success in solid tumours has been modest. In the past decade, a dozen Mabs have been investigated clinically for their potential usefulness in RIT of colorectal cancer.

Methods

The application of radiolabelled Mabs for the treatment of solid cancers is discussed, and clinical trials investigating RIT for colorectal cancer listed in the Medline and Embase databases are reviewed.

Results

Uptake of radiolabelled Mabs in tumour and, consequently, the therapeutic efficacy of RIT is inversely correlated with tumour size. The bone marrow is the most important dose-limiting organ. Twenty-three phase I/II studies were found that investigated the feasibility and efficacy of RIT using five radionuclides and 15 Mabs against carcinoembryonic antigen, tumour-associated glycoprotein 72, epithelial cellular adhesion molecule, A33 or colon-specific antigen p, mainly in patients with advanced colorectal cancer. A few responses were recorded but no particular antibody construct seemed superior.

Conclusion

RIT might be an effective adjuvant treatment modality in colorectal cancer. Future studies should focus on its application in patients with small-volume or minimal residual disease.
Effects of a selective cyclo-oxygenase 2 inhibitor on colonic anastomotic and skin wound integrity (Br J Surg 2004; 91: 1613-1618)
Authors: Guy R J , Watkins P E
Published: February 2005

The Editors welcome topical correspondence from readers relating to articles published in the Journal. Responses can be sent electronically via the BJS website (www.bjs.co.uk) or by post. All letters will be reviewed and, if approved, appear on the website. A selection of these will be edited and published in the Journal. Letters must be no more than 250 words in length. Letters submitted by post should be typed on A4-sized paper in double spacing and should be accompanied by a disk.
Binding Cooperativity of Two Different Lewis Acid Groups at the Edge of Ferrocene
Authors: Boshra Ramez , Sundararaman Anand , Zakharov Lev N. , Incarvito Christopher D. , Rheingold Arnold L. , Jäkle Frieder
Published: February 2005

The binding properties of heteronuclear bidentate Lewis acids, in which an organoboron and an organotin moiety are attached adjacent to each other at one of the Cp rings of ferrocene, have been studied. Treatment of [1,2‐fc(SnMe2Cl)(BClMe)] (1‐Cl) (fc = ferrocenediyl) with one equivalent of pyridine or 4‐dimethylaminopyridine (DMAP) resulted in diastereoselective complexation of boron. Adducts 2 and 3 have been studied by multinuclear NMR, and the stereoselectivity of complexation was further confirmed by single crystal X‐ray diffraction of 2. The importance of cooperative effects that involve an intramolecular B‐Cl⋅⋅⋅Sn interaction on the diastereoselectivity is evident from comparison with binding studies on the phenyl‐substituted analogue [1,2‐fc(SnMe2Cl)(BPhMe)] (1‐Ph). Complexation of 1‐Ph led to diastereomeric mixtures of adducts 4 and 5, respectively, which were identified by multinuclear NMR including NOESY experiments. The solid‐state structure of one of the diastereomers of 5 was confirmed by X‐ray crystallography. Facile isomerization was found in solution and the barrier of activation was determined by VT NMR studies (4: Δ${G{{\,{\ne}\hfill \atop 298\hfill}}}$ = 54.9±0.4 kJ mol−1; 5: Δ${G{{\,{\ne}\hfill \atop 298\hfill}}}$ = 70.3±0.1 kJ mol−1). Competitive binding of pyridine to 1‐Cl and [FcB(Cl)Me] (Fc = ferrocenyl) showed that cooperative effects between tin and boron lead to significant Lewis acidity enhancement. Binding of a second nucleophile in the presence of excess of base occurred also at boron. The novel zwitterionic complexes [1,2‐fc(BMe(py)2)(SnMe2Cl2)] (6) and [1,2‐fc(BMe(dmap)2)(SnMe2Cl2)] (7) formed, which consist of boronium cation and stannate anion moieties. The structure of 7 in the solid‐state was confirmed by X‐ray crystallography. Multinuclear NMR data and competition experiments indicate weak binding of chloride to tin in 7 and partial dissociation in solution.
A Study of [Co2(alkyne)(binap)(CO)4] Complexes (BINAP=(1,1′‐Binaphthalene)‐2,2′‐diylbis(diphenylphosphine))
Authors: Gibson Susan E. , Kaufmann Karina A. C. , Loch Jennifer A. , Steed Jonathan W. , White Andrew J. P.
Published: February 2005

Understanding the interaction of chiral ligands, alkynes, and alkenes with cobaltcarbonyl sources is critical to learning more about the mechanism of the catalytic, asymmetric Pauson–Khand reaction. We have successfully characterized complexes of the type [Co2(alkyne)(binap)(CO)4] (BINAP=(1,1′‐binaphthalene)‐2,2′‐diylbis(diphenylphosphine)) and shown that diastereomer interconversion occurs under Pauson–Khand reaction conditions when alkyne=HCCCO2Me. Attempts to isolate [Co2(alkyne)(binap)(CO)x] complexes with coordinated alkenes led to the formation of cobaltacyclopentadiene species.
Metastasis–An alternative hypothesis
Authors: Freireich Emil J , Kurzrock Razelle , Estrov Zeev
Published: February 2005

The currently accepted models of metastasis are inconsistent with many clinical observations of the natural history of cancer and its response to therapy. Specifically, the authors suggest that it is time for a “paradigm shift.” It is time to reject the “local, regional, systemic hypothesis” of cancer and replace it with a hypothesis more consistent with the clinical facts, specifically, that cancer exists in many different forms (i.e. localized disease arising from locally acting carcinogens, which can spread locally and should be treated locally, and cancer that arises as localized disease but evolves to more malignant invasive disease [the current model of metastasis]). The other forms of cancer are systemic disease, which is induced by systemic carcinogens, and cancer arising in multiple cells and multiple sites, giving rise to a picture described as metastatic cancer. The importance of this paradigm shift is that more attention would be focused on identifying systemically acting carcinogens as they relate to etiology and to molecular abnormalities in the neoplastic cells that might be targeted clinically. Recent advances in cancer treatment have demonstrated that molecules that target cancer cell molecular abnormalities (rather than tissue of origin, lymph node, or metastasis) such as bcr‐abl or mutations in a cellular receptor such as c‐kit or epidermal growth factor possess curative potential. In addition, more attention should be devoted to distinguishing between local tumors and systemic disease, using sophisticated molecular biologic techniques. Perhaps most important, there is a need to devise therapeutic strategies that would treat cancer as a systemic illness and hopefully have a substantial impact on overall cancer mortality. Cancer 2005. © 2005 American Cancer Society.
Anaplastic thyroid carcinoma
Authors: Kebebew Electron , Greenspan Francis S. , Clark Orlo H. , Woeber Kenneth A. , McMillan Alex
Published: February 2005

BACKGROUND

Anaplastic thyroid carcinoma (ATC) is rare but is one of the most aggressive human malignancies. Several prognostic factors have been observed in patients with ATC, and some experts advocate aggressive multimodal therapy in selected patients. However, it is unclear whether such an approach significantly improves survival. The authors analyzed prognostic factors and treatment outcomes in patients with ATC reported in the National Cancer Institute's Surveillance, Epidemiology, and End Results data base.

METHODS

The cohort consisted of 516 patients with ATC reported to 12 population‐based cancer registries between 1973 and 2000. Demographic, pathologic, and treatment data were used for univariate and multivariate survival analyses.

RESULTS

The mean patient age at diagnosis was 71.3 years, and there were 171 men and 345 women. Eight percent of patients had intrathyroidal tumors, 38% had extrathyroidal tumors and/or lymph node invasion, and 43% of patients had distant metastasis. The average tumor size was 6.4 cm (range, 1–15 cm). Sixty‐four percent of patients underwent surgical resection of their primary tumor, and 63% received external beam radiotherapy. The overall cause‐specific mortality rate was 68.4% at 6 months and 80.7% at 12 months. Univariate analysis showed that age < 60 years, female gender, intrathyroidal tumor, external beam radiotherapy, surgical resection, and combined surgical resection of tumor and radiotherapy were associated with a lower cause‐specific mortality. On multivariate analysis, only age < 60 years, an intrathyroidal tumor, and the combined use of surgical and external beam radiation therapy were identified as independent predictors of lower cause‐specific mortality.

CONCLUSIONS

Although most patients with ATC had an extremely poor prognosis, patients < 60 years old with intrathyroidal tumors survived longer. Surgical resection with external beam radiotherapy for ATC was associated with lower cause‐specific mortality. Cancer 2005. © 2005 American Cancer Society.
Geranylgeranylacetone inhibits lysophosphatidic acid‐induced invasion of human ovarian carcinoma cells in vitro
Authors: Hashimoto Kae , Morishige Ken‐ichirou , Sawada Kenjiro , Tahara Masahiro , Shimizu Shoko , Sakata Masahiro , Tasaka Keiichi , Murata Yuji
Published: February 2005

BACKGROUND

Lysophosphatidic acid (LPA) induced a dose‐dependent increase of cancer cell invasion by promoting Rho/Rho‐associated kinase signaling. Prenylation of Rho is essential for regulating cell growth, motility, and invasion. Geranylgeranylacetone (GGA), an isoprenoid compound, is used clinically as an antiulcer drug. Recent findings suggested that GGA might inhibit the small GTPase activation by suppressing prenylation. The authors hypothesized that the anticancer effects of GGA result from the inhibition of Rho activation.

METHODS

The authors examined the effect of GGA using an in vitro invasion assay in human ovarian carcinoma cells, and analyzed the mechanism of the GGA effect on Rho activation, stress fiber formation and focal adhesion assembly, which are essential processes for cell invasion.

RESULTS

The induction of ovarian carcinoma cell invasion by LPA was inhibited by the addition of GGA in a dose‐dependent manner. Treatment of cancer cells with GGA resulted in inactivation of Rho, changes in cell morphology, loss of stress fiber formation and focal adhesion assembly, and the suppression of tyrosine phosphorylation of focal adhesion proteins. The effect of GGA on cancer cells was partially prevented by the addition of geranylgeraniol, which is an intermediate of geranylgeranyl pyrophosphate and compensates geranylgeranylation of Rho.

CONCLUSIONS

The inhibition of LPA‐induced invasion by GGA was, at least in part, derived from suppressed Rho activation by preventing geranylgeranylation. Cancer 2005. © 2005 American Cancer Society.
A multicenter Phase II study of bortezomib in recurrent or metastatic sarcomas
Authors: Maki Robert G. , Kraft Andrew S. , Scheu Kelly , Yamada Jennifer , Wadler Scott , Antonescu Cristina R. , Wright John J. , Schwartz Gary K.
Published: February 2005

BACKGROUND

Based on evidence of activity in preclinical and Phase I studies, the authors undertook a study of bortezomib, a reversible proteasome inhibitor, for patients with metastatic sarcomas.

METHODS

Two arms were opened, each using a Simon two‐stage design. Arm A included patients with osteogenic sarcoma, Ewing sarcoma, and rhabdomyosarcoma. Arm B accrued patients with other types of soft tissue sarcomas. Patients were not allowed to have received previous chemotherapy for metastatic disease. The initial dose of bortezomib was a 1.5 mg/m2 intravenous push twice weekly followed by a rest week. The dose was escalated to 1.7 mg/m2 if patients tolerated Cycle 1 well. The dose escalation was eliminated due to toxicity observed in the first six patients.

RESULTS

Painful neuropathy, myalgias, and asthenia were the most significant observed toxicities. The most frequent toxicities included fatigue, diarrhea, constipation, and nausea. Pharmacodynamic data from 18 patients with complete data collection did not show consistent differences between patients with or without Grade 2 or Grade 3 neuropathy (toxicity graded according the National Cancer Institute Common Toxicity Criteria). Arm A had low accrual and was closed. One confirmed partial response among 21 evaluable patients was observed on Arm B in a patient with leiomyosarcoma. Due to the inactivity of this agent, the study was closed after the first stage of accrual.

CONCLUSIONS

Bortezomib has minimal activity in soft tissue sarcoma as a single agent. If studied further in sarcomas, bortezomib should be investigated in combination with agents with demonstrated preclinical synergy. Cancer 2005. © 2005 American Cancer Society.
Retinoic acid generated by Raldh2 in mesoderm is required for mouse dorsal endodermal pancreas development
Authors: Molotkov Andrei , Molotkova Natalia , Duester Gregg
Published: February 2005

Studies on nonmammalian vertebrate embryos have indicated that retinoic acid (RA) is required for pancreas development. We have analyzed mouse embryos carrying a null mutation of the gene encoding retinaldehyde dehydrogenase 2 (Raldh2), which controls RA synthesis. Raldh2−/− embryos specifically lack expression of Pdx1 (a homeobox gene required for pancreas development) and Prox1 in dorsal endodermal but not ventral endodermal pancreatic precursor tissues. Ventral endodermal expression of Hex is not affected in Raldh2−/− embryos, indicating that liver specification is not dependent upon RA. Also, expression of Foxa2 across the dorsoventral axis of the endoderm is not affected in Raldh2−/− embryos, indicating that a lack of RA does not cause a general defect in foregut endoderm development. Comparison of wild‐type and Raldh2−/− embryos carrying an RA‐reporter transgene demonstrates that RA activity is normally present throughout the endoderm except in the ventral‐most region but is totally missing in endoderm of Raldh2−/− embryos. Thus, Raldh2 expressed in adjacent splanchnic lateral plate mesoderm provides an RA signal to dorsal endoderm. Dorsal Pdx1 expression is rescued in Raldh2−/− embryos by low‐dose maternal administration of RA, which preferentially restores RA‐reporter expression in the dorsal endoderm. Our findings demonstrate a specific role for RA in mouse embryos as a mesodermally synthesized signal needed for dorsal endodermal expression of Pdx1 during development of the dorsal pancreatic lineage. Developmental Dynamics 232:950–957, 2005. © 2005 Wiley‐Liss, Inc.
JNK and ROKα function in the noncanonical Wnt/RhoA signaling pathway to regulate Xenopus convergent extension movements
Authors: Kim Gun‐Hwa , Han Jin‐Kwan
Published: February 2005

The Wnt/planar cell polarity (PCP) pathway plays a critical role in wing, eye, and sensory bristle development of Drosophila and in convergent extension (CE) movements during vertebrate gastrulation. In Drosophila, Jun N‐terminal kinase (JNK) and Rho‐associated kinase (ROK) participate in RhoA‐mediated PCP pathway during eye and wing development. In mammalian cells, Rac1 and Cdc42 but not RhoA are required for JNK activation by Wnt/PCP signals. However, there has been no evidence that Rho GTPases regulate JNK activation in Wnt/PCP pathway during Xenopus CE movements. Here, we report that Xenopus RhoA (XRhoA), but not Xenopus Cdc42 (XCdc42), is essential for JNK activation downstream of the Wnt/PCP pathway during Xenopus CE movements, and the phenotypic effect of loss of XRhoA function was rescued by Xenopus JNK1 (XeJNK1). In addition, XRhoA rescues the inhibition of CE movements by the DEP domain deletion mutant of Xenopus Dsh (Xdsh‐ΔDEP), which has dominant negative (DN) effects on JNK activation, and the PDZ domain deletion mutant of Xdsh (Xdsh‐ΔPDZ). Moreover, we demonstrate that Xenopus Rho‐associated kinase α (xROKα), which is expressed mainly in mesoderm and ectoderm that undergo extensive cell rearrangements, regulates CE movements without affecting gene expression, and injection of xROKα rescued the inhibition of CE movements caused by DN XRhoA. Finally, we show that ROKα and JNK synergistically rescued embryos overexpressing DN XRhoA, which exhibit gastrulation defects, although ROKα is not required for JNK activation. Together, these data suggest that JNK and ROKα function in the noncanonical Wnt/RhoA pathway to regulate Xenopus CE movements. Developmental Dynamics 232:958–968, 2005. © 2005 Wiley‐Liss, Inc.
her9 promotes floor plate development in zebrafish
Authors: Latimer Andrew J. , Shin Jimann , Appel Bruce
Published: February 2005

Notochord, floor plate, and in anamniotes hypochord, are vertebrate embryonic midline structures that are the sources of molecules that pattern the nervous system, somites, and dorsal aorta. Midline precursor cells arise from the dorsal organizer during gastrulation, and Notch signaling is an important regulator of midline cell fate specification. To understand fully how Notch signaling regulates midline development, we investigated the role of potential Notch target genes. We show here that midline precursors express her9, a member of the hairy/Enhancer of split gene family. Although her9 inhibits notochord development and promotes floor plate specification, her9 expression in floor plate cells appears not to require Notch signaling. We show that, instead, her9 is a downstream effector of Nodal signaling for floor plate specification. Developmental Dynamics 232:1098–1104, 2005. © 2005 Wiley‐Liss, Inc.
Foxn1 is required for tissue assembly and desmosomal cadherin expression in the hair shaft
Authors: Johns Sarah A. , Soullier Stephan , Rashbass Penny , Cunliffe Vincent T.
Published: February 2005

The mouse nude mutation inactivates the gene encoding the Foxn1 transcription factor, causing defective hair morphogenesis. Here, we show for the first time that Foxn1 is required for proper assembly of the hair medulla, and we identify Foxn1‐regulated genes by transcript profiling. One such gene encodes the desmosomal cadherin, Dsc2. Significantly, Foxn1‐dependent Dsc2 expression is restricted to the hair medulla, and within these cells, Dsc2 protein is predominantly localized to specialized adhesion junctions between the cortex and the medulla. Our results reveal Foxn1 as an essential regulator of tissue assembly in the growing hair shaft and implicate Dsc2 as a downstream effector of this activity. Developmental Dynamics 232:1062–1068, 2005. © 2005 Wiley‐Liss, Inc.
Integrin repertoire on myogenic cells changes during the course of primary myogenesis in the mouse
Authors: Cachaço Ana Sofia , Pereira Carlos Silva , Pardal Rita G. , Bajanca Fernanda , Thorsteinsdóttir Sólveig
Published: February 2005

Cells interact with the extracellular matrix through receptors, most commonly of the integrin family. We (Cachaço et al. [2003] Development 130:1659–1671) and others (Schwander et al. [2003] Dev. Cell 4:673–685) have demonstrated a role for β1 integrins in mouse primary myogenesis. However, it is unclear what α subunits pair with β1 during this process in vivo. Here, we determined α subunit expression patterns at embryonic day (E) 11.5–E14.5. Differentiated myotomal myocytes express all α subunits studied. As the muscle masses form both in trunk (E12.5) and limbs (E11.5–E12.5), laminin receptors α6β1 and α7β1 are undetectable, and an assembled laminin matrix is absent. Instead α1β1, α4β1, α5β1, and an αv‐containing integrin are expressed and unassembled laminin and fibronectin are abundant around myogenic cells. At E13.5–E14.5, α6β1 and α7β1 are expressed, and a laminin matrix forms around individual myotubes. Thus, myogenic cells change their integrin expression pattern during the course of primary myogenesis in the mouse, suggesting different roles for fibronectin‐ and laminin‐containing matrices in this process. Developmental Dynamics 232:1069–1078, 2005. © 2005 Wiley‐Liss, Inc.
Human alpha rhythms during visual delayed choice reaction time tasks: A magnetoencephalography study, Human Brain Mapping 2005;24(3):184–192
Authors: Babiloni Claudio , Babiloni Fabio , Carducci Filippo , Cincotti Febo , Del Percio Claudio , Della Penna Stefania , Franciotti Raffaella , Pignotti Sandro , Pizzella Vittorio , Rossini Paolo Maria , Sabatini Elisabetta , Torquati Kathya , Romani Gian Luca
Published: February 2005

The original article to which this Erratum refers was published in the March 2005 issue of Human Brain Mapping Human Brain Mapping (2005) 24(3) 184–192.
Accuracy and efficiency of atomic basis set methods versus plane wave calculations with ultrasoft pseudopotentials for DNA base molecules
Authors: Pulay Peter , Saebo Svein , Malagoli Massimo , Baker Jon
Published: February 2005

Recent results from Preuss et al. (J Comput Chem 2004, 25, 112) on DNA base molecules, obtained by plane wave density functional calculations using ultrasoft pseudopotentials, are compared with calculations using Gaussian basis sets. Bond lengths and angles agree closely, but dihedral angles and vibrational frequencies show significant differences. The Gaussian basis calculations are at least an order of magnitude more efficient than the plane wave/ultrasoft pseudopotential calculations at a similar level of accuracy; the advantage is even larger if the Fourier Transform Coulomb method is used. To obtain definite benchmark values, the geometries of the four DNA bases were optimized at the MP2 level with large basis sets, up to cc‐pVQZ and aug‐cc‐pVTZ. © 2005 Wiley Periodicals, Inc. J Comput Chem 26: 599–605, 2005
Simultaneous determination of noradrenaline and dopamine in Portulaca oleracea L. by capillary zone electrophoresis
Authors: Yue Mei‐E , Jiang Ting‐Fu , Shi Yan‐Ping
Published: February 2005

A simple and rapid capillary electrophoretic method was developed for the simultaneous determination of noradrenaline (NA) and dopamine (DA) in Portulaca oleracea L. The buffer solution used in this method was 40 mM tris (hydroxymethyl) aminomethane (Tris)‐H3PO4 at pH 2.00 containing 15% methanol. The effects of pH value, organic modifier, and applied voltage were investigated. The linear ranges of NA and DA were 0.5–100 μg/mL (r = 0.9952) and 6.25–200 μg/mL (r = 0.9992), respectively. The relative standard deviations of the corrected peak area were 6.73% and 4.26%, respectively. NA and DA in Portulaca oleracea L. were simultaneous determined successfully within 5.6 min. In this way, the contents of NA and DA in different parts (stem, leaves, and seeds) of P. oleracea L. and in different extracts of leaves with different solvents (distilled water, 50% methanol, and methanol) were studied.
Quantitative determination of antalarmin, a novel corticotropin‐releasing hormone receptor‐1 antagonist, in canine plasma by HPLC‐MS
Authors: Fox Stephen D. , Roman John M. , Cizza Giovanni , Veenstra Timothy D. , Issaq Haleem J.
Published: February 2005

A simple and rapid method was developed for the quantitation of antalarmin from plasma using high performance liquid chromatography coupled with electrospray ionization mass spectrometry (ESI/MS). Separation of antalarmin from interfering compounds was achieved using reversed phase chromatography on a C‐8 micro‐column with an isocratic mobile phase comprised of 80% acetonitrile, 20% water, and 5 mM triethylamine. Detection by ESI/MS was accomplished in positive ion mode using single ion monitoring of the protonated molecular ions of antalarmin and its 13C2‐isotopimer. The area ratio of the integrated peaks of interest in the extracted ion chromatogram was used for quantitation. The lower limit of detection was 1 picogram (pg) and the quantitation showed a linear response up to 4 nanograms loaded on column. To achieve acceptable accuracy at or around the limit of quantitation of 20 pg, a 1/x weighting was applied to the calibration data. Accuracy and precision variation for intra and inter‐day validation were below the acceptable limit (15%) for pharmacokinetic studies.
The full evaporation technique: A promising alternative for residual solvents analysis in solid samples
Authors: Brault Audrey , Agasse Valérie , Cardinael Pascal , Combret Jean‐Claude
Published: February 2005

The static headspace technique is the most common approach to residual solvent analysis in pharmaceutical and environmental matrices. This paper presents an alternative tool where the volatile impurities are released from the matrix by working directly on a small amount of sample at a high equilibration temperature: the so‐called Full Evaporation Technique (FET). The capability of this method was evaluated on a mixture of nine solvents, which belong to Class 3 in the classification of the European Pharmacopoeia Agency for residual solvents, at various levels of concentration: ethanol, acetone, 2‐propanol, methyl acetate, 2‐butanone, ethyl acetate, tetrahydrofuran, 2‐methyl‐1‐propanol, 1‐butanol. Data on linearity, accuracy, precision and sensitivity are reported. Use of an internal standard proved to be necessary when using such a method. The method is then successfully applied to the analysis of solvent traces in permethylated β‐cyclodextrin.
Influence of the pore structure on the properties of silica based reversed phase packings for LC
Authors: Szabó Zoltan , Ohmacht Robert , Huck Christian W. , Stöggl Wolfgang M. , Bonn Günther K.
Published: February 2005

This paper describes the preparation and investigation of new, highly loaded, monomeric, silica based, reversed phase C18 and C30 packings. The influence of pore structure and endcapping on the properties of C18 and C30 packings is described. Using hydrothermal procedures, silicas with predictable pore size (9.3–25.5 nm) and surface area have been prepared. Silylation with long chain silanes substantially alters the pore structure of the silica: pore size and pore volume decrease. A new parameter, the volumetric surface coverage [mm3×m–2] has been introduced. This parameter – calculated from on‐column measured porosity data – indicates the pore volume portion occupied by the hydrocarbon chains. Endcapping does not significantly change the pore structure of the bonded phases. The reduced retentions (reduced with respect to unit area: [k/m2]) – a good measure for comparing the retention behaviour of packings with different surface areas – are similar for most of the phases, demonstrating good accessibility of the pores for the solutes. Slightly lower retentions were found on the endcapped than on the non‐endcapped phases for probes with dense π‐electron system (e. g. polyaromatic hydrocarbons) demonstrating the contribution of silanophilic interactions to the retention. The phases had been successfully used for various demanding separations, e. g. for the separation of flavonoids, carotenoids, resveratrol, and tocopherol isomers, fullerenes, and anions.
Nanoscale Blends between Immiscible Polymers via Simultaneous Non‐Interfering Polymerisation
Authors: Zinck Philippe , Brachais Claire‐Hélène , Finot Eric , Barbier‐Baudry Denise
Published: February 2005

Summary: An important topic in polymer science seeks to improve the performances of polymer blends using nanoscale phase segregation. Here, blends between polystyrene and polycaprolactone are realised by a chemical route. The non‐interfering character of the radical polymerisation of styrene and the lanthanide halide initiated ring‐opening polymerisation of caprolactone is assessed. The molecular weights range from 2 000 to 3 500 for polycaprolactone and up to 140 000 for polystyrene, with reasonable polydispersity indexes. From calorimetry measurements, it is shown that polystyrene and low molecular weight polycaprolactone are immiscible. The morphology of the blends between the two immiscible polymers studied by atomic force microscopy is consistent with nanometer‐scale phase segregation.

AFM surface image of a nanoscale blend.

magnified image

AFM surface image of a nanoscale blend.
Synthesis and Optical Properties of a New Series of Side‐Chain Poly(amic acid)s With p‐π Conjugation
Authors: Li Najun , Lu Jianmei , Yao Shechun
Published: February 2005

Summary: After the condensation polymerization of benzoguanamine (BGA) and pyromellitic dianhydride (PMDA) under microwave irradiation, the resulting p‐π conjugate poly(amic acid) was grafted via the azo coupling reaction. The obtained side‐chain polymers were further grafted with TDI‐aliphatic alcohol derivatives and TDI‐aniline derivatives. The third‐order NLO coefficient and response time of PAA and graft polymers were measured by degenerated four wave mixing (DFWM) technique and their fluorescent properties were also investigated. All of the graft polymers have larger NLO coefficients and film‐formability than PAA. Their fluorescent properties were also changed by the different electronic effect of the side‐chains. The influences of the introduction of side‐chains, the side‐chain length and the electronic effect of the substituting groups on the azobenzol side‐chain to both optical properties of the polymers by varying the conjugation degree were investigated.

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Cationic Copolymerization Behavior of Glycidyl Phenyl Ether with Seven‐Membered Cyclic Carbonate
Authors: Morikawa Hiroshi , Sudo Atsushi , Nishida Haruo , Endo Takeshi
Published: February 2005

Summary: To clarify the cationic copolymerization behavior of epoxide and cyclic carbonate, the copolymerization behavior of glycidyl phenyl ether (GPE) with seven‐membered cyclic carbonate (7CC) was carried out using methyl trifluoromethanesulfonate (MeOTf) as a cationic initiator. The addition of 7CC accelerated the consumption rate of GPE, and the resulting copolymers were richer in 7CC‐derived unit compared to the feed ratio of 7CC. During the copolymerization, a large amount of five‐membered cyclic carbonate having a phenoxymethyl group (PM‐5CC) was produced as a by‐product, which suggests the corresponding spiroorthocarbonate was formed as an intermediate and that residual oxytetramethylene (OTM) unit was incorporated into the copolymer sequence. From 1H NMR analysis, it was found that the copolymers had a statistically random sequence consisting of GPE, 7CC, and OTM units.

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Atom Transfer Radical Polymerization of Solketal Acrylate Using Cyclohexanone as the Solvent
Authors: Zhen Yuee , Wan Shourong , Liu Yuanqin , Yan Husheng , Shi Rongfu , Wang Chunhong
Published: February 2005

Summary: Solketal acrylate (SA) was homopolymerized by atom transfer radical polymerization (ATRP) using CuBr/N,N,N′,N″,N″‐pentamethyldiethylenetriamine as the catalyst and cyclohexanone as the solvent with controlled molecular weights and low polydispersities. The prepared bromine‐terminated homopolymers, PSA, were used as macroinitiators to initiate polymerization of tert‐butyl acrylate (tBA) under similar ATRP conditions to produce diblock copolymers, PSA‐b‐PtBA, with controlled molecular weights and low polydispersities. ATRP of SA using bromine‐terminated PtBA as the macroinitiator was also carried out and diblock copolymers, PtBA‐b‐PSA, were obtained. The PSA block was selectively hydrolyzed by stirring for 3 h in 6 N HCl/THF (1/9, v/v) at room temperature to form a poly(glycerol monoacrylate) block. Both blocks of PSA and PtBA were hydrolyzed by stirring in anhydrous trifluoroacetic acid (TFA)/dichloromethane for 4 h, then adding water to the system and stirring for another 3 h to form corresponding diblock copolymers of glycerol monoacrylate and acrylic acid.

Kinetic plot for the atom transfer radical polymerization of solketal acrylate at 90 °C.

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Kinetic plot for the atom transfer radical polymerization of solketal acrylate at 90 °C.
Interpolymer Complexes between Hydroxypropylcellulose and Copolymers of Maleic Acid: A Comparative Study
Authors: Bumbu Gina‐Gabriela , Vasile Cornelia , Chitanu Gabrielle Charlotte , Staikos Georgios
Published: February 2005

Summary: The formation of interpolymer complexes (IPCs) between hydroxypropylcellulose (HPC) and copolymers of maleic acid with vinyl acetate (MAc‐VA), acrylic acid (MAc‐AA) and styrene (MAc‐S) in aqueous solution has been investigated by turbidimetry, viscometry and fluorescence measurements. The viscosity data indicated a compact structure for the IPCs between HPC and maleic acid copolymers. Besides H‐bonding, strong hydrophobic forces materialize between HPC and MAc‐S, strengthening this IPC. The strength of the interpolymer interactions was estimated to increase in the order: HPC:MAc‐VA < HPC:MAc‐AA < HPC:MAc‐S. The IPCs of HPC with MAc‐VA or MAc‐AA were water‐soluble at pH values higher than 3, while the IPC between HPC and MAc‐S was water‐soluble at pH values above 4.5.

Cloud point temperature of different interpolymer complexes as a function of copolymer concentration.

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Cloud point temperature of different interpolymer complexes as a function of copolymer concentration.
Cover Picture: Macromol. Chem. Phys. 5/2005
Authors: Bumbu Gina‐Gabriela , Vasile Cornelia , Chitanu Gabrielle Charlotte , Staikos Georgios
Published: February 2005

Cover: The formation and stability of interpolymer complexes (IPCs) of hydoxypropylcellulose with different copolymers of maleic acid depend on the hydrophobic/hydrophilic balance of the copolymers. The solubility of the IPCs decreases by lowering the pH.

Further details can be found in the Full Paper by G.‐G. Bumbu,* C. Vasile, G. C. Chitanu, and G. Staikos on page 540.
Ciprofloxacin‐induced chorea
Authors: Azar Susan , Ramjiani Amisha , Van Gerpen Jay A.
Published: February 2005

A reply to this letter has been published in Movement DisordersMov Disord (2005) 20 (4) 514.
Enabling location‐based services in wireless LAN hotspots
Authors: Chen Yen‐Cheng , Chan Yao‐Jung , She Cheung‐Wo
Published: February 2005

The wide deployment of IEEE 802.11 Wireless LAN (WLAN) makes possible application services developed in WLAN hotspots. Owing to the small cell size in WLAN hotspots, it is practical to develop location‐based services with the awareness of the WLAN access points (APs) that mobile devices currently access. In this paper, we propose an effective location determination technique using the inherent SNMP support in WLAN APs. It is shown that the current location of a mobile device can be determined from the SNMP traps sent by APs. Since the SNMP‐based approach doesn't need any particular software or hardware in mobile devices, location‐based services can be widely deployed, especially in public WLAN hotspots. To further enable location‐based services through the WWW, this paper also considers the location determination of a mobile device from its IP address, retrieved in a WWW environment. In addition, we propose a web service framework for location‐based services in WLAN hotspots. Thus, location‐based services can be developed in a standard way. Copyright © 2005 John Wiley & Sons, Ltd.
Efficient authenticated key agreement protocols resistant to a denial‐of‐service attack
Authors: Tseng Yuh‐Min
Published: February 2005

Malicious intruders may launch as many invalid requests as possible without establishing a server connection to bring server service to a standstill. This is called a denial‐of‐service (DoS) or distributed DoS (DDoS) attack. Until now, there has been no complete solution to resisting a DoS/DDoS attack. Therefore, it is an important network security issue to reduce the impact of a DoS/DDoS attack. A resource‐exhaustion attack on a server is one kind of denial‐of‐service attack. In this article we address the resource‐exhaustion problem in authentication and key agreement protocols. The resource‐exhaustion attack consists of both the CPU‐exhaustion attack and the storage‐exhaustion attack. In 2001, Hirose and Matsuura proposed an authenticated key agreement protocol (AKAP) that was the first protocol simultaneously resistant to both the CPU‐exhaustion attack and the storage‐exhaustion attack. However, their protocol is time‐consuming for legal users in order to withstand the DoS attack. Therefore, in this paper, we propose a slight modification to the Hirose–Matsuura protocol to reduce the computation cost. Both the Hirose–Matsuura and the modified protocols provide implicit key confirmation. Also, we propose another authenticated key agreement protocol with explicit key confirmation. The new protocol requires less computation cost. Because DoS/DDoS attacks come in a variety of forms, the proposed protocols cannot fully disallow a DoS/DDoS attack. However, they reduce the effect of such an attack and thus make it more difficult for the attack to succeed. Copyright © 2005 John Wiley & Sons, Ltd.
Preparation and characterization of novel conducting polyaniline–perlite composites
Authors: Arsalani Nasser , Hayatifar Mohammad
Published: February 2005

The development of composites displaying electrical conductivity has attracted significant research attention over the last decade due to the possibility of new applications. For the first time, we describe the preparation of composites in which perlite particles have been combined with the well‐known conducting polyaniline (PAni). Such composites have been prepared by the in situ deposition of a thin coating of chemically synthesized polyaniline onto perlite particles (diameter <250 µm). These composite materials have been characterized by FT‐IR spectroscopy, scanning electron microscopy, thermogravimetric analysis and four‐point probe conductivity measurements. In addition, the effects of reaction time, perlite particle size and type of protonic acid medium on the conductivities of the composites have been investigated. Their conductivities were also compared to those of mechanical blends of polyaniline and perlite. Copyright © 2005 Society of Chemical Industry
Comparative structural analysis of TonB‐dependent outer membrane transporters: Implications for the transport cycle
Authors: Chimento David P. , Kadner Robert J. , Wiener Michael C.
Published: February 2005

TonB‐dependent outer membrane transporters (TBDTs) transport organometallic substrates across the outer membranes of Gram‐negative bacteria. Currently, structures of four different TBDTs have been determined by X‐ray crystallography. TBDT structures consist of a 22‐stranded β‐barrel enclosing a hatch domain. Structure‐based sequence alignment of these four TBDTs indicates the presence of highly conserved motifs in both the hatch and barrel domains. The conserved motifs of the two domains are always in close proximity to each other and interact. We analyzed the very large interfaces between the barrel and hatch domains of TBDTs and compared their properties to those of other protein–protein interfaces. These interfaces are extensively hydrated. Most of the interfacial waters form hydrogen bonds to either the barrel or the hatch domain, with the remainder functioning as bridging waters in the interface. The hatch/barrel interfacial properties most resemble those of obligate transient protein complexes, suggesting that the interface is conducive to conformational change and/or movement of the hatch within the barrel. These results indicate that TBDTs can readily accommodate substantial conformational change and movement of their hatch domains during the active transport cycle. Also, these structural changes may require only modest forces exerted by the energy‐coupling TonB protein upon the transporter. Proteins 2005. © 2005 Wiley‐Liss, Inc.
Optical and electrical properties of oriented thin films of oligomer containing betaine‐type moiety in side chain
Authors: Muzikante I. , Fonavs E. , Tokmakov A. , Cepite D. , Stiller B. , Brehmer L. , Neilands† O.
Published: February 2005

Non‐linear optical and electrical properties of polymer films obtained by dipole orientation of active units are reported. Novel polar oligomer with N‐(indan‐1,3‐dion‐2‐yl)pyridinium betaine (IPB) as a side group is studied. Orientation of polar groups in oligomer thin films causes an increase of the photo‐induced change of surface potential on irradiation in the region of photo‐induced electron transfer (PIET) where the IPB group exhibits a reversible change of the value and sign of the dipole moment. At longer wavelengths, the value of the surface potential of the oligomer may be determined by transport of photo‐generated charge carriers. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ethyl anion preferred conformation
Authors: Goodman Lionel , Sauers Ronald R.
Published: February 2005

Ab initio architecture and torsional barrier for ethyl anion, C2Hare analyzed using natural bond orbital methodology. The B3LYP/6‐311++G(3df,2p) 2‐kcal/mol torsional barrier between the preferred staggered and higher‐energy eclipsed conformer is calculated to be one‐third lower than for ethane. This decrease is largely attributed to reduced hyperconjugative stabilization of the equilibrium anion conformer compared to that for ethane. Proton removal is also predicted to cause opening of the ethane central CCH angle by 7°, attributed to decreased steric repulsion and to increased hyperconjugative stabilization accompanying angle widening in the ion. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005