bluuebunny/crossref_metadata_2025 huggingface dataset:
Radiation therapy for hepatocellular carcinoma
Authors: Hawkins Maria A. , Dawson Laura A.
Published: March 2006

Technologic advances have provided the means to deliver tumoricidal doses of radiation therapy (RT) to patients with unresectable hepatocellular carcinoma (HCC) while avoiding critical normal tissues, providing the opportunity to use RT for curative intent treatment of HCC. For the current report, the expanded role of external beam RT in the setting of HCC from palliation to cure was reviewed. A systematic literature search was undertaken using the MEDLINE data base and secondary references to identify peer‐reviewed, English‐language articles that reported clinical outcomes after external beam RT alone or in combination with other treatments for HCC. Abstracts from the 2005 American Society of Clinical Oncology, American Society for Therapeutic Radiology and Oncology, American Gastrointestinal Association, and Society of Surgical Oncology Gastrointestinal Cancer Symposium also were included in the search. More than 60 articles reporting on clinical outcomes among patients who received RT for HCC have been published since 1990, including 20 articles that described unique sets of at least 15 patients. RT was used for palliation, to improve local control, and with curative intent in a wide spectrum of patients who most often were unsuitable for surgery and other treatments. Pain reduction following RT was noted in approximately 75% of patients with bone metastases from HCC who received RT. For patients with liver‐confined disease treated with conformal RT, proton beam RT, and/or image guided RT with or without transarterial chemoembolization (TACE), local control response rates ranged from 40% to 90%, and the median survival ranges from 10 months to 25 months. For patients with HCC who had portal vein thrombus, the median survival after RT to treat the thrombus and/or the hepatic tumor with or without TACE ranged from 5.3 months to 9.7 months. Although outcomes after high‐dose conformal RT for liver‐confined HCC were excellent, the potential survival benefit of RT should be tested in randomized controlled trials that require international collaboration. Cancer 2006. © 2006 American Cancer Society.
Localization of retinaldehyde dehydrogenases and retinoid binding proteins to sustentacular cells, glia, Bowman's gland cells, and stroma: Potential sites of retinoic acid synthesis in the postnatal rat olfactory organ
Authors: Asson‐Batres Mary Ann , Smith W. Bradford
Published: March 2006

Work from our laboratory suggests that retinoic acid (RA) influences neuron development in the postnatal olfactory epithelium (OE). The studies reported here were carried out to identify and localize retinaldehyde dehydrogenase (RALDH) expression in postnatal rat OE to gain a better understanding of potential in vivo RA synthesis sites in this continuously regenerating tissue. RALDH 1, 2, and 3 mRNAs were detected in postnatal rat olfactory tissue by RT‐PCR analysis, but RALDH 1 and 2 transcripts were predominant. RALDH 1 immunoreactivity was localized to sustentacular cells in the OE and to Bowman's gland cells, and GFAP+/p75− olfactory ensheathing cells (OECs) in the underlying lamina propria (LP). RALDH 2 did not colocalize with RALDH 1, but appeared to be expressed in GFAP−/RALDH 1− OECs as well as in unidentified structures in the LP. Cellular RA binding protein (CRABP II) colocalized with RALDH 1. Cellular retinol/retinaldehyde binding protein (CRBP I) was localized to RALDH 1+ sites in the OE and LP and RALDH 2+ sites, primarily surrounding nerve fiber bundles in the LP. Vitamin A deficiency altered RALDH 1, but not RALDH 2 protein expression. The isozymes and binding proteins exhibited random variability in levels and areas of expression both within and between animals. These findings support the hypothesis that RA is synthesized in the postnatal OE (catalyzed by RALDH 1) and underlying LP (differentially catalyzed by RALDH 1 and RALDH 2) at sites that could influence the development, maturation, targeting, and/or turnover of olfactory receptor neurons throughout the olfactory organ. J. Comp. Neurol. 496:149–171, 2006. © 2006 Wiley‐Liss, Inc.
Selective spread of neurotropic herpesviruses in the rat hippocampus
Authors: Sík Attila , Coté Amélie , Boldogkõi Zsolt
Published: March 2006

Transsynaptically spreading viruses are widely used for tracing neuronal circuits in both the central and peripheral nervous systems. However, viruses are capricious tools with selective spreading properties that can produce false‐negative results. Using herpes simplex virus type 1 and two pseudorabies virus strains, we aimed at mapping quantitatively neuronal connections in the rat hippocampus. We found that none of the tested viruses infected CA3 pyramidal neurons across synapses following inoculation into the CA1 area. Combined injections of the viruses with the retrograde tracer cholera toxin B (CTB) resulted in CTB, but not virus labeling of CA3 pyramidal neurons. In contrast, other brain regions known to send inputs to the CA1 (the entorhinal cortex, medial septum and diagonal band of Broca, raphe nuclei) were transsynaptically infected. Our results indicate that Schaffer collaterals of CA3 pyramidal cells lack the appropriate cellular machinery for successful neurotropic herpesvirus infection. After injections of viruses into the dentate gyrus/CA3 area, we found labeling in commissurally projecting mossy cells and their afferent granule cells but not in contralateral CA3 pyramidal cells. Using this unique spreading property, we estimated that single mossy cells receive input from a compact cluster of 30–40 granule cells. J. Comp. Neurol. 496:229–243, 2006. © 2006 Wiley‐Liss, Inc.
Site‐specific estrogen and progestin regulation of orphanin FQ/nociceptin and nociceptin opioid receptor mRNA expression in the female rat limbic hypothalamic system
Authors: Sinchak Kevin , Romeo Horacio E. , Micevych Paul E
Published: March 2006

The distributions of orphanin FQ (OFQ/N; also known as nociceptin) and its cognate receptor, opioid receptor‐like receptor‐1 (NOP), overlap steroid‐responsive regions throughout reproductive circuits of the limbic system and hypothalamus. For example, in the ventromedial nucleus of the hypothalamus (VMH), OFQ/N facilitates lordosis in female rats through estrogen and progesterone regulation of nociceptin activity. We studied estrogen and progesterone regulation of OFQ/N and NOP mRNA expression in limbic‐hypothalamic reproductive circuits. Ovariectomized rats were treated with 17β‐estradiol‐benzoate (2 μg) and 26 hours later with oil or progesterone (500 μg) and were killed 30 hours after initial treatment. Alternate brain sections were processed for OFQ/N or NOP mRNA in situ hybridization. High levels of hybridization for NOP and OFQ/N and overlapping distributions were observed throughout the limbic hypothalamic reproductive circuits; however, in VMH, only NOP expression was observed. Estrogen treatment increased NOP mRNA expression in anteroventral periventricular nucleus (AVPV), median preoptic nucleus, and VMH. Subsequent progesterone treatment did not alter estrogen‐induced expression of NOP mRNA in VMH or median preoptic nucleus but reduced expression in the AVPV. OFQ/N mRNA levels were also regulated by steroids. In the caudal part of the posterodorsal medial amygdala, estrogen increased OFQ/N mRNA levels, and progesterone did not alter this increase, whereas, in the medial part of the medial preoptic nucleus, estrogen and progesterone were needed to increase OFQ/N mRNA levels. Steroid regulation of OFQ/N and NOP in the medial preoptic nucleus and VMH is consistent with emerging data indicating that this opioid system regulates female reproduction. J. Comp. Neurol. 496:252–268, 2006. © 2006 Wiley‐Liss, Inc.
Coordination Chemistry and Diphenylacetylene Hydrogenation Catalysis of Planar Chiral Ferrocenylphosphane‐Thioether Ligands with Cyclooctadieneiridium(I)
Authors: Malacea Raluca , Manoury Eric , Routaboul Lucie , Daran Jean‐Claude , Poli Rinaldo , Dunne John P. , Withwood Adrian C. , Godard Cyril , Duckett Simon B.
Published: March 2006

The reaction of the P,S ligands CpFe{1,2‐C5H3(PPh2)(CH2SR)},(1‐R; R = Et, Ph, tBu), with 0.5 equivalents of [Ir(COD)Cl]2 (metal/ligand = 1:1) furnishes the stable mononuclear adducts [Ir(COD)Cl(1‐R)], 2‐R, in high yields. The molecular structures of the three complexes 2‐R have been determined by single‐crystal X‐ray diffraction. Compounds 2‐Et and 2‐Ph have similar five‐coordinate molecular structures, with an intermediate coordination geometry between a distorted trigonal‐bipyramid and a distorted square‐pyramid. In the solid state, the sulfur atom chirality (R group exo, lone pair endo and parallel to the Cp‐Fe axis) as well as the iridium chirality (Cl atom exo relative to the ferrocene group) is controlled by the ligand planar chirality. In solution, only one diastereoisomer is observed in both cases, indicating that the geometries observed in the solid state are maintained in solution, or that the different species are in rapid exchange on the NMR time scale. Complex 2‐tBu, on the other hand, shows a four‐coordinate square‐planar molecular structure with a dangling thioether moiety, probably for steric reasons. For metal/ligandratios greater than 1, the compounds [Ir(COD){κ2‐P:S‐(1‐R)}]+[Ir(COD)Cl2]– (3‐R) are obtained, resulting from the chloride abstraction by the excess iridium metal on complex 2‐R. The structure of 3‐Ph was confirmed by single‐crystal X‐ray diffraction. A rapid equilibration between 2‐R and 3‐R gives rise to only one set of NMR signals for each metal/ligand ratio. For the ligand 1‐tBu, a similar equilibration between 2‐tBu and 3‐tBu is again observed, in addition to a slower equilibration with a third product, [Ir(COD)Cl](μ‐1‐R)[Ir(COD)Cl] (4‐tBu), which is proposed to contain a bridging P,S ligand spanning two Ir centres. Complex 2‐Ph reacts with [Rh(COD)Cl]2 to give only the heterometallic ionic pair [Ir(COD){κ2‐P:S‐(1‐Ph)}][Rh(COD)Cl2] without transfer of ligand 1‐Ph from Ir to Rh. Furthermore, the rhodium complex RhCl(COD)(1‐Ph) reacts quantitatively with [Ir(COD)Cl]2 at room temp. to yield 2‐Ph and [Rh(COD)Cl]2, thereby illustrating the much stronger affinity of ligands 1‐Ph for iridium compared to rhodium. Finally, the complexes 2‐tBu and 2‐Ph were found to be efficient catalysts for the diphenylacetylene hydrogenation, affording a mixture of monohydrogenation [both (E)‐ and (Z)‐stilbene] and dihydrogenation (1,2‐diphenylethane) products. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Self‐Aggregation of Synthetic Zinc Chlorins Possessing a 13‐Ester‐Carbonyl Group as Chlorosomal Chlorophyll Models
Authors: Kunieda Michio , Tamiaki Hitoshi
Published: March 2006

We have synthesized zinc 31‐hydroxychlorins 1–4 possessing a methoxycarbonyl group at the 13‐position by modifying naturally occurring chlorophyll‐a. Synthetic zinc chlorins 1–4 have three specific substituents, namely 31‐OH, central Zn and 13‐C=O moieties, along the Qy axis, and 1–3 self‐aggregate in an aqueous medium containing Triton X‐100, as do natural bacteriochlorophylls in the main light‐harvesting antennas (chlorosome) of green photosynthetic bacteria. The 13‐methoxycarbonyl group in 1–3 is a prerequisite for such self‐aggregation, while the other methoxycarbonyl groups at the 151‐ and/or 172‐positions are not. This indicates that such a linear situation of these substituents is significant for chlorosomal self‐aggregation of chlorophyllous pigments and also that the 13‐methoxycarbonyl group is an alternative to the 13‐keto‐carbonyl group in natural pigments. Furthermore, the resulting oligomers of 1–3 have fluorescence emission peaks at less than 700 nm, which are considerably more blue‐shifted than previously prepared self‐aggregates of chlorins possessing the 13‐keto‐carbonyl group fixed onto an exo five‐membered ring, and are a new class of artificial light‐harvesting systems. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
CuI/DABCO‐Catalyzed Cross‐Coupling Reactions of Aryl Halides with Arylboronic Acids
Authors: Li Jin‐Heng , Wang De‐Ping
Published: March 2006

CuI combined with DABCO (1,4‐diaza‐bicyclo[2.2.2]octane) was developed as an inexpensive and efficient catalytic system for the Suzuki–Miyaura cross‐coupling of aryl halides with arylboronic acids. The couplings between aryl iodides and arylboronic acids catalyzed by catalytic amounts of CuI and DABCO proceeded smoothly in moderate to excellent yields. However, the CuI/DABCO system was less efficient in the reactions of aryl bromides, and a higher reaction temperature was required to improve the yield. For the less activated aryl bromides, a stoichiometric amount of CuI together with TBAB was necessary to obtain satisfactory yields. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2006)
Comparison of GMRES and ORTHOMIN for the black oil model on unstructured grids
Authors: Li Wenjun , Chen Zhangxin , Huan Guanren , Sun Xiuzhen
Published: March 2006

This paper addresses an application of ORTHOMIN and GMRES to petroleum reservoir simulation using the black oil model on unstructured grids. Comparisons between these two algorithms are presented in terms of storage and total flops per restart step. Numerical results indicate that GMRES is faster than ORTHOMIN for all tested petroleum reservoir problems, particularly for large scale problems. The control volume function approximation method is utilized in the discretization of the governing equations of the black oil model. This method can accurately approximate both the pressure and velocity in the simulation of multiphase flow in porous media, effectively reduce grid orientation effects, and be easily applied to arbitrarily shaped control volumes. It is particularly suitable for hybrid grid reservoir simulation. Copyright © 2006 John Wiley & Sons, Ltd.
Possible involvement of increase in spinal fibronectin following peripheral nerve injury in upregulation of microglial P2X4, a key molecule for mechanical allodynia
Authors: Nasu‐Tada Kaoru , Koizumi Schuichi , Tsuda Makoto , Kunifusa Emiko , Inoue Kazuhide
Published: March 2006

We have recently demonstrated that the P2X4receptor, an ATP‐gated cation channel, in spinal microglia is a key molecule that mediates the mechanical allodynia induced by peripheral nerve injury. Although microglial P2X4receptor expression is increased after peripheral nerve injury, the molecular mechanism(s) underlying its upregulation remains largely unknown. Fibronectin is a member of the extracellular matrix molecules and is actively produced in response to injury and diseases in the CNS. Here, we describe the influence of fibronectin on P2X4receptor expression in microglia and the upregulation of fibronectin after peripheral nerve injury. Microglia that were cultured on fibronectin‐coated dishes showed a marked increase in P2X4receptor expression, both at the mRNA and protein levels, as compared to those cultured on control dishes. Fibronectin also enhanced the microglial Ca2+responses mediated by P2X4receptors. Moreover, Western blot examination of the spinal cord from a rat with spinal nerve injury indicated that fibronectin was upregulated on the ipsilateral side. Interestingly, intrathecal injection of ATP‐stimulated microglia to the rat lumber spinal cord revealed that microglia cultured on fibronectin‐coated dishes was more effective in the induction of allodynia than microglia cultured on control dishes. Taken together, our results suggest that spinal fibronectin is elevated after the peripheral nerve injury and it may be involved in the upregulation of the P2X4receptor in microglia, which leads to the induction of neuropathic pain. © 2006 Wiley‐Liss, Inc.
Computational study of ground‐state chiral induction in small peptides: Comparison of the relative stability of selected amino acid dimers and oligomers in homochiral and heterochiral combinations
Authors: Zhou Yu , Oostenbrink Chris , Jongejan Aldo , Van Gunsteren Wilfred F. , Hagen Wilfred R. , De Leeuw Simon W. , Jongejan Jaap A.
Published: March 2006

The relative stabilities of homochiral and heterochiral forms of selected dipeptides, AA, AS, AC, AV, AF, AD, AK, tripeptides, AAA, AVA, and an acetylpentapeptide, AcGLSFA, have been calculated using thermodynamic integration protocols and the GROMOS 53A6 force field. Integration pathways have been designed that produce minimal disturbance to the system, including the use of soft atoms, low‐energy intermediates, and chiral inversion of the smaller amino acid in the peptide. Comparison of the results obtained by thermodynamic integration between the diastereomeric forms (in explicit water, at 300 K) and from exhaustive global minimum‐energy searches for the individual dipeptides (implicit water, ε = 78, 0 K) suggests that entropic contributions to the relative stability of the chiral forms are important. This conclusion is supported by the results of explicit calculation of the effect of temperature on the relative stability of alanylvalylalanine diastereomers. The Gibbs free energy calculations predict that at ambient temperature and pressure homochiral dipeptides with small side chains or polar groups in the vicinity of the peptide backbone, AA, AS, and AD, are more stable than their heterochiral counterparts by fractions of a kJ/mol. For bigger side chains, AC, AV, AF, and AK, the heterochiral diastereomers appear to be more stable. Predicted relative stabilities are in line with observations reported in the literature for AE and YY. Excellent agreement is found for the calculated and experimentally determined relative stabilities of the diastereomers of the dipeptide AA and of all‐L AcGLSFA and its diastereomer containing D‐serine in the central position. Addition of counterions to the solvent box has no significant effects on charged and neutral forms. From the present findings it would appear unlikely that the intrinsic stability difference between homo‐ and heterochiral dipeptides has been a driving force in a primordial selection process leading to the incorporation of amino acids with a single enantiomeric configuration in natural proteins. © 2006 Wiley Periodicals, Inc. J Comput Chem 27: 857–867, 2006
Immune responses to AAV in a phase I study for Canavan disease
Authors: McPhee S. W. J. , Janson C. G. , Li C. , Samulski R. J. , Camp A. S. , Francis J. , Shera D. , Lioutermann L. , Feely M. , Freese A. , Leone P.
Published: March 2006

Background

Canavan disease is a rare leukodystrophy with no current treatment. rAAV‐ASPA has been developed for gene delivery to the central nervous system (CNS) for Canavan disease. This study represents the first use of a viral vector in an attempt to ameliorate a neurodegenerative disorder.

Methods

Subjects received intracranial infusions via six cranial burr holes. Adeno‐associated virus, serotype 2 (AAV2), mediated intraparenchymal delivery of the human aspartoacylase cDNA at a maximum dose of 1 × 1012 vector genomes per subject. The immune response and safety profiles were monitored in the follow‐up of ten subjects.

Results

Following rAAV2 administration, we found no evidence of AAV2 neutralizing antibody titers in serum for the majority of subjects tested (7/10). In a subset (3/10) of subjects, low to moderately high levels of AAV2 neutralizing antibody with respect to baseline were detected. In all subjects, there were minimal systemic signs of inflammation or immune stimulation. In subjects with catheter access to the brain lateral ventricle, cerebrospinal fluid was examined and there was a complete absence of neutralizing antibody titers with no overt signs of brain inflammation.

Conclusions

rAAV2 vector administration to the human CNS appears well tolerated. The low levels of immune response to AAV2 detected in 3/10 subjects in this study suggest at this dose and with intraparenchymal administration this approach is relatively safe. Long‐term monitoring of subjects and expansion to phase II/III will be necessary in order to make definitive statements on safety and efficacy. Copyright © 2006 John Wiley & Sons, Ltd.
Simultaneous determination of spironolactone and its active metabolite canrenone in human plasma by HPLC‐APCI‐MS
Authors: Dong Haijuan , Xu Fengguo , Zhang Zunjian , Tian Yuan , Chen Yun
Published: March 2006

A sensitive and specific liquid chromatography‐atmospheric pressure chemical ionization‐mass spectrometry (LC‐APCI‐MS) method for the simultaneous determination of spironolactone and its active metabolite canrenone in human plasma has been developed and validated. After the addition of estazolam as the internal standard (IS), plasma samples were extracted with methylene chloride : ethyl acetate mixture (20 : 80, v/v) and separated by high‐performance liquid chromatography (HPLC) on a reversed‐phase C18 column with a mobile phase of methanol–water (57 : 43, v/v). Analytes were determined in a single quadrupole mass spectrometer using an atmospheric pressure chemical ionization (APCI) source. LC‐APCI‐MS was performed in the selected‐ion monitoring (SIM) mode using target ions at m/z 341.25 for spironolactone and canrenone, m/z 295.05 for estazolam. The method was proved to be sensitive and specific by testing six different plasma batches. Calibration curves of spironolactone and canrenone were linear over the range 2–300 ng/ml. The within‐ and between‐batch precisions (relative standard deviation (RSD)%) were lower than 10% and the accuracy ranged from 85 to 115%. The lower limit of quantification (LLOQ) was identifiable and reproducible at 2 ng/ml. The proposed method was successfully applied to study the pharmacokinetics of spironolactone and its major metabolite in healthy male Chinese volunteers. Copyright © 2006 John Wiley & Sons, Ltd.
Derivatisation of arginine residues with malondialdehyde for the analysis of peptides and protein digests by LC‐ESI‐MS/MS
Authors: Foettinger Alexandra , Leitner Alexander , Lindner Wolfgang
Published: March 2006

In this study a selective tagging strategy for the derivatisation of arginine residues in peptides is presented. It is based on the reaction of the guanidine group of the arginine side‐chain with malondialdehyde (MDA) under strongly acidic conditions, in which a stable pyrimidine ring is formed. The reaction conditions have been optimised so that quantitative modification can be achieved for a variety of peptides.

The label has a strong influence on the polarity and basicity of the arginine side‐chain and thus on the chromatographic and mass spectrometric properties of arginine‐containing peptides. For example, retention, particularly of small and polar peptides as well as arginine‐rich peptides, is significantly increased by derivatisation, and therefore sensitivity is also enhanced in liquid chromatography‐mass spectrometry (LC‐MS). The arginine side‐chain also has a strong impact on the fragmentation behaviour of peptides in tandem mass spectrometry. This has been investigated for standard peptides for which, in some cases, significantly more fragment ions were formed after derivatisation. Finally, the method was tested for tryptic digests of standard proteins to demonstrate how the tagging strategy can give improved or complementary information for protein identification. Copyright © 2006 John Wiley & Sons, Ltd.
Absolute quantification of Atlantic salmon and rainbow trout vitellogenin by the ‘signature peptide’ approach using electrospray ionization QqToF tandem mass spectrometry
Authors: Cohen Alejandro M. , Mansour Atef A. H. , Banoub Joseph H.
Published: March 2006

In this work, we present a simple method for absolute quantification of plasma vitellogenin from both rainbow trout and Atlantic salmon. Plasma samples obtained from control and β‐estradiol induced fish were digested with trypsin. A characteristic ‘signature peptide’ was selected and analyzed by high performance liquid chromatography (HPLC) coupled to an electrospray quadrupole‐time‐of‐flight tandem mass spectrometer, using a deuterated homolog peptide as an internal standard. The hybrid tandem mass spectrometer was operated in a ‘pseudo’ selected reaction‐monitoring mode in which three diagnostic product ions were monitored for identification and quantification purposes. The reproducibility (coefficient of variation ∼5%) and sensitivity (limit of quantification (LOQ) of 0.009 mg/ml) achieved by this simple assay allow it to be considered as an alternative to immunological assays. Copyright © 2006 John Wiley & Sons, Ltd.
Toll‐like receptors in central nervous system glial inflammation and homeostasis
Authors: Kielian Tammy
Published: March 2006

Toll‐like receptors (TLRs) are a family of pattern‐recognition receptors expressed on cells of the innate immune system that allow for the recognition of conserved structural motifs on a wide array of pathogens, referred to as pathogen‐associated molecular patterns, as well as some endogenous molecules. The recent emergence of studies examining TLRs in the central nervous system (CNS) indicates that these receptors not only play a role in innate immunity in response to infectious diseases but may also participate in CNS autoimmunity, neurodegeneration, and tissue injury. This review summarizes the experimental evidence demonstrating a role for TLRs in the context of CNS inflammation in both infectious and noninfectious conditions. © 2006 Wiley‐Liss, Inc.
Comprehensive two‐dimensional HPLC to study the interaction of multiple components in Rheum palmatum L. with HSA by coupling a silica‐bonded HSA column to a silica monolithic ODS column
Authors: Hu Lianghai , Li Xin , Feng Shun , Kong Liang , Su Xingye , Chen Xueguo , Qin Feng , Ye Mingliang , Zou Hanfa
Published: March 2006

A mode of comprehensive 2‐D LC was developed by coupling a silica‐bonded HSA column to a silica monolithic ODS column. This system combined the affinity property of the HSA column and the high‐speed separation ability of the monolithic ODS column. The affinity chromatography with HSA‐immobilized stationary phase was applied to study the interaction of multiple components in traditional Chinese medicines (TCMs) with HSA according to their affinity to protein in the first dimension. Then the unresolved components retained on the HSA column were further separated on the silica monolithic ODS column in the second dimension. By hyphenating the 2‐D separation system to diode array detector and MS detectors, the UV and molecular weight information of the separated compounds can also be obtained. The developed separation system was applied to analysis of the extract of Rheum palmatum L., a number of low‐abundant components can be separated on a single peak from the HSA column after normalization of peak heights. Six compounds were preliminarily identified according to their UV and MS spectra. It showed that this system was very useful for biological fingerprinting analysis of the components in TCMs and natural products.
Random and Sequential Copolypeptides Containing O‐Phospho‐L‐Threonine and L‐Aspartic Acid; Roles in CaCO3 Biomineralization
Authors: Hayashi Shinya , Ohkawa Kousaku , Yamamoto Hiroyuki
Published: March 2006

Summary: The present study describes the synthesis of novel polypeptides containing O‐phospho‐L‐threonine [Thr(PO3H2)] and L‐aspartic acid. Random copolypeptides copoly[Thr(PO3H2)XAspY] (X:Y = 25:75, 50:50, 75:25), were conventionally prepared by copolymerization of Thr(PO3Ph2) N‐carboxyanhydride (NCA) and Asp(OBzl) NCA followed by deprotection of the phenyl and benzyl groups by catalytic hydrogenolysis over PtO2. Polycondensation of the protected peptide p‐nitrophenyl esters [Thr(PO3Ph2)]Z‐Asp(OBzl)‐ONp and subsequent deprotection yielded the sequential polypeptides poly[Thr(PO3H2)Z‐Asp] (Z = 1–4). By using the synthetic polypeptides, their effects on the growth of CaCO3 crystals were examined. In the poly[Thr(PO3H2)Z‐Asp]/CaCO3 systems, brushlike calcite and spherical vaterite were formed, with the former being found at [Ca2+]/[Res] ratios of ≥180, ≥140, ≥120, and ≥100 for Z = 1, 2, 3, and 4, respectively. These results indicate that an increase of Thr(PO3H2) residues in the repetitive unit induces the characteristic brushlike calcite, a fact indicating that Thr(PO3H2) residues can modify the CaCO3 crystal morphology.

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Synthesis of Highly Hydrophilic Polyaniline Nanowires and Sub‐Micro/Nanostructured Dendrites on Poly(propylene) Film Surfaces
Authors: Zhong Wenbin , Chen Xianhong , Liu Shoumei , Wang Yongxin , Yang Wantai
Published: March 2006

Summary: Polyaniline (PANI) nanowires and sub‐micro/nanostructured dendrites are synthesized and immobilized on PP‐g‐PAA film surfaces via routine oxidative polymerization of aniline under different conditions, where grafting poly(acrylic acid) (PAA) served as a template and dopant, and SDS as a surfactant. The immobilized PANI enhances the surface hydrophilicity of the poly(propylene) (PP) films, and a superhydrophilic surface is obtained in this way. The mechanism of forming different morphologies of PANI and of correspondingly obtaining a superhydrophilic surface are briefly discussed.

FESEM image shows the PANI sub‐micro/nanostructured dendrites immobilized on the surfaces of PP films. The modified surface is highly hydrophilic with a water contact angle of 3°.

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FESEM image shows the PANI sub‐micro/nanostructured dendrites immobilized on the surfaces of PP films. The modified surface is highly hydrophilic with a water contact angle of 3°.
Computational Studies of RAFT Polymerization–Mechanistic Insights and Practical Applications
Authors: Coote Michelle L. , Krenske Elizabeth H. , Izgorodina Ekaterina I.
Published: March 2006

Summary: Computational chemistry is a valuable complement to experiments in the study of polymerization processes. This article reviews the contribution of computational chemistry to understanding the kinetics and mechanism of reversible addition fragmentation chain transfer (RAFT) polymerization. Current computational techniques are appraised, showing that barriers and enthalpies can now be calculated with kcal accuracy. The utility of computational data is then demonstrated by showing how the calculated barriers and enthalpies enable appropriate kinetic models to be chosen for RAFT. Further insights are provided by a systematic analysis of structure‐reactivity trends. The development of the first computer‐designed RAFT agent illustrates the practical utility of these investigations.

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Patterning Layered Polymeric Multilayer Films by Room‐Temperature Nanoimprint Lithography
Authors: Lu Yingxi , Hu Wei , Ma Ying , Zhang Lianbin , Sun Junqi , Lu Nan , Shen Jiacong
Published: March 2006

Summary: Polyelectrolyte multilayer films of poly(acrylic acid) (PAA)/poly(allylamine hydrochloride) (PAH) and PAH/poly(sodium 4‐styrenesulfonate) (PSS) based on electrostatic interactions as a driving force are patterned by room‐temperature nanoimprint lithography (RT‐NIL). Under an imprinting pressure of 40 bar for 8 min, well‐defined pattern structures with a line width of ≈330 nm and a separation of ≈413 nm are achieved. Meanwhile, hydrogen‐bonding‐directed multilayer films of poly(vinyl pyrrolidone) (PVPON)/poly(methyl acrylic acid) (PMAA) and poly(4‐vinylpyridine)/PAA can also be patterned in a similar way by RT‐NIL. The successful imprinting of these films originates from the high compressibility and fluidity of the layered polymeric films under high pressure.

SEM image of an imprinted (PAH/PAA)*20 film on silicon wafer.

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SEM image of an imprinted (PAH/PAA)*20 film on silicon wafer.
Nanofibrous Membranes Containing Carbon Nanotubes: Electrospun for Redox Enzyme Immobilization
Authors: Wang Zhen‐Gang , Xu Zhi‐Kang , Wan Ling‐Shu , Wu Jian , Innocent Christophe , Seta Patrick
Published: March 2006

Summary: Nanofibrous membranes that possess reactive groups are fabricated by the electrospinning process from PANCAA solutions that contain MWCNTs. Field emission scanning electron microscopy is used to evaluate the morphology and diameter of the nanofibers. Potentials for applying these nanofibrous membranes to immobilize redox enzymes by covalent bonding are explored. It is envisaged that the electrospun nanofibrous membranes could provide a large specific area and the MWCNTs could donate/accept electrons for the immobilized redox enzymes. Results indicate that, after blending with MWCNTs, the diameter of the PANCAA nanofiber increases slightly. The PANCAA/MWCNT nanofibrous membranes immobilize more enzymes than that without MWCNTs. Moreover, as the concentration of the MWCNTs increases, the activity of the immobilized catalase is enhanced by about 42%, which is mainly attributed to the promoted electron transfer through charge‐transfer complexes and the π system of MWCNTs.

The covalent immobilization of redox enzymes, such as catalase, on a PANCAA/MWCNTs nanofiber.

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The covalent immobilization of redox enzymes, such as catalase, on a PANCAA/MWCNTs nanofiber.
Field Effect Devices Based on SrTiO3 Gate Dielectrics for the Investigation of Charge Carrier Mobility in Macromolecular Films
Authors: Cassinese Antonio , Barra Mario , Biasiucci Mariano , D'Angelo Pasquale
Published: March 2006

Field effect devices (FET) allow an exhaustive investigation of the electronic transport properties of innovative semiconductors of interest for new applications in modern electronics. In this contribution, we report on the fabrication and characterization of FET devices where SrTiO3 (STO) single crystals and organic macromolecular compounds, such as doped and undoped polythiophenes, or poly(N‐vinylcarbazole) (PVK), are used as insulating and semiconducting layers, respectively. STO, with εr of about 300, offers the possibility to strongly modulate the charge carrier density in the organic films, thus overcoming the limitations related to the use of more conventional oxides.
Morphology Evolution During Polymer Crystallization Simultaneous Calorimetric and Optical Measurements
Authors: De Santis Felice , Vietri Anna Rosa , Pantani Roberto
Published: March 2006

The crystallization of the isotactic poly(propylene) (I‐PP) has been studied carrying out measurements by means of a special calorimeter connected to a microscope and a digital acquisition system of images. To authors' knowledge, this is the first time that simultaneous calorimetric and optical measurements are carried out on polymers. The analysis of Polarized Optical Microscopy images has allowed the appraisal of nucleation density and growth rate in isothermal and non isothermal conditions. The results obtained in isothermal conditions have been analyzed through the Kolmogoroff model and the crystallinity calculated from the model has been compared with that obtained from the calorimetric measurements.
Nano‐composite Fibers Based on Poly(p‐benzamide)‐Montmorillonite
Authors: Marsano Enrico , Azzurri Francesco , Corsini Paola
Published: March 2006

Nano‐composites fibers made of poly(p‐benzamide) (PBA), a rigid liquid crystalline polymer, and an inorganic nano‐filler, montmorrilonite (MMT), were prepared by a wet spin process. Dimethylacetamide‐3% (w/w) LiCl was used as a solvent. Polymer concentration, Cp = 6.5% (w/w), was maintained as high as possible, but lower than the critical concentration for the appearance of a liquid crystalline phase, Cp′ = 6.7%. MMT dispersed in PBA solution was 2.6–5.0% (w/w) with respect to PBA. The Polymer‐MMT solutions show a liquid crystalline phase at polymeric concentration above 6.7% and they show by a high metastability and a slow phase separation. The PBA‐MMT solutions show good spinnability and fibers are characterized by a significant increasing in modulus and breaking strength. WAXD and TEM analyses suggest that partially intercalated PBA/MMT nano‐composite fibers have been obtained.
Optically Active Methacrylic Polymers Bearing in the Side Chain the (S)‐3‐Hydroxypyrrolidinyl Group Linked totrans‐bisazoaromatic Chromophore: Synthesis and Characterization
Authors: Angiolini Luigi , Benelli Tiziana , Giorgini Loris , Mauriello Francesco , Salatelli Elisabetta
Published: March 2006

The synthesis by radical homopolymerization of a novel optically active methacrylic polymer containing a side‐chain chiral moiety linked to a photochromic bisazoaromatic chromophore has been carried out starting from the related monomer (S)‐3‐methacryloyloxy‐1‐[4′‐phenylazo‐(4‐azobenzene)]‐pyrrolidine [(S)‐MPAAP]. The polymeric derivate has been fully characterized and its spectroscopic properties compared to those of the monomer and of the corresponding homopolymer bearing only one azoaromatic chromophore in the side chain. The optical activity displayed by the bisazo polymer is discussed in terms of extent of chiral conformation assumed by the macromolecules as a consequence of dipole‐dipole interactions between the bisazoaromatic chromophores.
Synthesis of Polymers Containing Second Order NLO‐Active Thiophene and Thiazole Based Chromophores
Authors: Caruso Ugo , Diana Rosita , Fort Alain , Panunzi Barbara , Roviello Antonio
Published: March 2006

Grounding on the evidence that thiophene or thiazole rings in donor‐acceptor chromophoric systems promote enhancement of charge transfer and nonlinear optical responses, in this work NLO properties have been investigated of organic polymers containing azoic chromophores based on dinitrothiophene or nitrothiazole moieties. It has been carried out the azo coupling reaction directly between a series of copolymers and diazonium salts containing the etherocyclic group at different grafting percentages.
Thermal Expansion Coefficients of the Axes of the Unit Cell of Syndiotactic 1,2‐Poly(1,3‐Butadiene)
Authors: Napolitano Roberto , Pirozzi Beniamino , Esposito Simona
Published: March 2006

Samples of syndiotactic 1,2‐poly(1,3‐butadiene) subjected to different thermal and mechanical treatments have been characterized by DSC and X‐ray. The treatments induce changes in the crystallinity, crystal size and size of the unit cell, but do not evidence polymorphism. Values of the thermal expansion coefficients of the axes of the unit cell have been determined by X‐ray measurements at various temperatures.
iPP Based Nanocomposites Filled with Calcium Carbonate Nanoparticles: Structure/Properties Relationships
Authors: Avella Maurizio , Cosco Simona , Lorenzo Maria Laura Di , Pace Emilia Di , Errico Maria Emanuela , Gentile Gennaro
Published: March 2006

Isotactic polypropylene (iPP) based nanocomposites filled with calcium carbonate nanoparticles (CaCO3) were prepared by melt mixing and structure‐properties relationships of the nanomaterials were studied. Elongated CaCO3 nanopowders coated with two different coating agents, polypropylene‐maleic anhydride graft copolymer (iPP‐g‐MA) and fatty acids (FA), were tested as nanoreinforced phases. The influence of surface treatment of the nanoparticles on the polymer/nanofillers interfacial adhesion and on the final materials properties was investigated. Morphological analysis showed that the selected coating agents induce different iPP/nanofiller adhesion degrees. Young's modulus increases as a function of the nanoparticles content and the coating agent nature. Finally, all the prepared nanocomposites showed a significant improvement of iPP barrier properties either to oxygen or to carbon dioxide.
The Crystallization and Melting Processes of Poly(L‐lactic acid)
Authors: Di Lorenzo Maria Laura
Published: March 2006

A throughout investigation of crystallization and melting behavior of poly(L‐lactic acid) is detailed in this contribution. Crystallization analyses, conducted in both isothermal and non‐isothermal conditions, revealed the occurrence of a sudden acceleration in phase transition rate in the temperature range between 100 and 118 °C. This unusual increase, due to very high rates of spherulite growth, seems not related to morphological changes of PLLA spherulites, nor to unexpected variations in nucleation rate. DSC analyses disclosed multiple melting behavior of PLLA, depending on crystallization temperature. At low temperatures the very high crystallization rates lead to the achievement of low values of crystalline degree, with formation of small and/or defective crystals, which have a large tendency to reorganize into more stable structures during the heating scan that leads to complete fusion. The multiple melting process of PLLA was also analyzed at different heating rates.
Predictors of weight loss in Parkinson's disease
Authors: Uc Ergun Y. , Struck Lynn K. , Rodnitzky Robert L. , Zimmerman Bridget , Dobson Judith , Evans William J.
Published: March 2006

The objective of this study was to examine the change of body weight (BW) among Parkinson's disease (PD) patients and controls over years and determine the predictors of weight loss among PD patients. Studies on weight loss in PD studies are cross‐sectional, have a short follow‐up, or lack in clinical detail. We examined the percentage of BW change over years among 49 PD patients and 78 controls. The controls were from another study on longitudinal evolution of BW and body composition in the elderly. We determined the BW, Hoehn and Yahr (HY) stage, and dyskinesia status of 49 consecutive nondemented PD patients with symptom duration of 6.1 ± 0.7 years (mean ± SEM) and ascertained their BW at the time of diagnosis and 2.4 ± 0.2 years before the diagnosis from medical records. We collected data again 7.2 ± 0.5 years after the first visit. The PD group lost 7.7% ± 1.5% of BW over the entire symptomatic period (13.1 ± 0.8 years), while the control group lost only 0.2% ± 0.7% of BW over 9.9 ± 0.1 years; weight loss was clinically significant (>5%) in 55.6% of PD patients vs. 20.5% of the controls (both P values < 0.001, adjusted for sex, baseline age, and observation period duration). PD patients lost weight in both the early and advanced phases. While worsening of parkinsonism was the most important factor, age at diagnosis, emergence of visual hallucinations, and possibly dementia were also associated with weight loss. We demonstrated significant weight loss in PD patients compared to controls over approximately 1 decade. Neurodegeneration involving both motor and nonmotor systems may be associated with weight loss in PD. © 2006 Movement Disorder Society
New global a priori estimates for the third‐grade fluid equations
Authors: Steinhauer Mark , Urbano José Miguel , Videman Juha
Published: March 2006

This note bridges the gap between the existence and regularity classes for the third‐grade Rivlin–Ericksen fluid equations. We obtain a new global a priori estimate, which conveys the precise regularity conditions that lead to the existence of a global in time regular solution. Copyright © 2006 John Wiley & Sons, Ltd.
The differential role of prostaglandin E2 receptors EP3 and EP4 in regulation of fever
Authors: Lazarus Michael
Published: March 2006

The innate immune system of mammals is able to detect bacteria when they infect local tissue or enter the blood stream, and initiate an immediate immune response. Prostaglandin (PG) E2 is considered as the most important link between the peripheral immune system and the brain. Due to four PGE2 receptors (EP receptors) and their differential expression in various areas of the hypothalamus and brain stem, PGE2 mediates different components of the acute phase reaction. A fever model is discussed in which the preoptic area contains the mechanisms for both hyperthermic and hypothermic responses and EP receptors in the median preoptic area (MnPO) modulate the thermogenic system. The neuron‐specific modulation of EP receptors in the MnPO can be critically tested by using Cre‐recombinase‐mediated DNA recombination in genetically engineered mice. A concept for mice with conditional expression of EP3R and EP4R to investigate the different roles of those receptors in lipopolysaccharide (LPS)‐induced fever is presented.
Estrogens modulate the gene expression of Wnt‐7a in cultured endometrial adenocarcinoma cells
Authors: Wagner Jörg , Lehmann Leane
Published: March 2006

The glycoprotein Wnt‐7a participates in a signaling pathway that transmits information among uterine cell types. Disruption of this pathway by the transplacentally acting carcinogen diethylstilbestrol (DES) is associated with morphological abnormalities of the female reproductive tract (FRT). This raises the question whether estrogens in the diet might also interfere with this pathway. Therefore, this study investigated the influence of the steroid hormone 17β‐estradiol (E2), the mycotoxin zearalenone (ZEN), the soy phytoestrogen genistein (GEN), and DES on the expression of Wnt‐7a in an endometrial adenocarcinoma cell line (Ishikawa cells) by reverse transcription/competitive PCR. In addition, the enzymatic activity of alkaline phosphatase (ALP) was determined, which is estrogen receptor (ER)‐dependently regulated in Ishikawa cells. After treatment of Ishikawa cells with E2, ZEN, GEN, and DES, a decrease in the gene expression of Wnt‐7a was observed. Maximum effect (50% reduction) was observed after treatment with concentrations that induced maximum expression of the ALP. Experiments in the presence of the ER antagonist (ICI 182,780) suggested that the ER is involved in the regulation of Wnt‐7a in Ishikawa cells. In conclusion, interference with the expression of Wnt genes in the FRT might be a novel mechanism by which estrogens disrupt the function of the FRT.
Stage‐dependent Dishevelled‐1 expression during mouse spermatogenesis suggests a role in regulating spermatid morphological changes
Authors: Ma Pengpeng , Wang Huizhen , Guo Rui , Ma Quanhong , Yu Zuoren , Jiang Yi , Ge Yehua , Ma Jing , Xue Shepu , Han Daishu
Published: March 2006

Dishevelled (Dsh in Drosophila or DVL in mice) is a member of the highly conserved Wg/Wnt signaling pathway, which regulates important processes such as cell proliferation, polarity, and specification of cell fate. Three orthologous genes of Dishevelled (Dvl‐1, Dvl‐2, and Dvl‐3) have been found in both humans and mice. They play pivotal roles in regulating cell morphology and a variety of changes in cell behaviors. In the present study, we show that the expression of Dvl‐1 is stage‐dependent during mouse spermatogenesis, although Dvl‐2 and Dvl‐3 show relative consistent expression. The expression of Dvl‐1 mRNA first appears in pachytene spermatocytes, increases in round and elongating spermatids, and then turns to an undetectable level in mature sperm cells. Analyses of immunohistochemistry and immunofluorescence staining show that DVL‐1 is present diffusely in the cytoplasm of pachytene spermatocytes and exhibits mainly a vesicular pattern and perinuclear distribution and a weak diffusely cytoplasmic signal in round and elongating spermatids. The vesicular pattern of DVL‐1 has been observed by previous studies in somatic cells, and suggested to play roles in signal transduction. Immunoprecipitation experiments show that DVL‐1 coimmunprecipitates with spermatogenic cells β‐actin rather than α‐tubulin. These results indicate that DVL‐1 may be involved in spermatid morphological changes during mouse spermiogenesis through mediating signal transduction and/or regulating actin cytoskeleton organization. Mol. Reprod. Dev. © 2006 Wiley‐Liss, Inc.
Priority and dynamic scheduling in a make‐to‐stock queue with hyperexponential demand
Authors: Jain Apurva
Published: March 2006

We consider the scheduling problem in a make‐to‐stock queue with two demand classes that can be differentiated based on their variability. One class experiences Poisson arrivals and the other class experiences hyperexponential renewal arrivals. We provide an exact analysis of the case where the demand class with higher variability is given non‐preemptive priority. The results are then used to compare the inventory cost performance of three scheduling disciplines, first‐come first‐serve and priority to either class. We then build on an existing dynamic scheduling heuristic to propose a modification that works well for our system. Extensions of the heuristic to more than two classes and to the case where demand state is known are also discussed. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006.