bluuebunny/crossref_metadata_2025 huggingface dataset:
Divinyl sulfide and its selenium and tellurium analogs as starting materials for the preparation of polyfunctional alkyl, aromatic, and heteroaromatic vinyl chalcogenides
Authors: Gavrilova Galina M. , Amosova Svetlana V.
Published: September 2006

Divinyl sulfide and its selenium and tellurium analogs have been used as starting materials for the introduction of vinylchalcogeno groups by reaction of halogenoalkanes, epichlorohydrin, polybromoorganyl sulfides or sulfoxides, perfluoro(chloro)benzenes, and dihalogenopyridines with sodium vinylchalcogenate. This approach has enabled the preparation of polyfunctional vinylsulfanyl derivatives of perfluoro(chloro)benzenes, which are applied for the synthesis of N‐, O‐, and S‐containing heterocyclic systems. The structures of the new compounds have been confirmed by IR and 1H, 13C, 19F NMR spectroscopy. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:491–498, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20270
Polyvalent iodine in organic chemistry: Recent developments, 2002–2005
Authors: Matveeva E. D. , Proskurnina M. V. , Zefirov N. S.
Published: September 2006

In the last three years, great strides were achieved in the field of organic chemistry of polyvalent iodine compounds. This paper includes the published works on this field from 2002–2005 (Zhdankin, V. V.; Stang, P. J Chem Rev 2002, 102, 2523–2584; Stang, P. J. J Org Chem 2003, 68, 2997–3008; Wirth, T.; Hirt, U. H. Synthesis 1999, 1271–1287; Morales‐Rojas, H.; Moss, R. A. Chem Rev 2002, 102, 2497–2521). It focuses on eight areas: (1) hypervalent iodine reagents as mild oxidants, (2) the addition of hypervalent iodine compounds to alkenes, (3) fluorination of organic compounds by hypervalent iodine compounds, (4) some new reactions of nucleophilic substitution of hypervalent iodine moiety, (5) iodine(III) compounds as a source of nitrene and carbene moiety, (6) novel and new iodine(III) compounds and methods of their preparation, (7) polyvalent iodine compounds in synthesis of natural compounds, and (8) miscellaneous. The published works focus on some hypervalent iodine reagents that have received a widespread practical application in organic chemistry. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:595–617, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20273
Transformation of copper(I) thiophosphite complexes into copper(I) clusters bridged by diisopropyldisulfides and diethyldisulfides
Authors: Kursheva Lidiya I. , Kataeva Olga N. , Krivolapov Dmitry B. , Batyeva Elvira S. , Sinyashin O. G.
Published: September 2006

The cleavage of coordination bonds in copper(I) halide thiophosphite complexes with the following transformation of the PS containing ligands in metal coordination sphere results in new cluster compounds bridged by disulfides. Thus, polymeric and tetrameric complexes of Cu(I) halides with thiophosphite ligands (triethyltrithiophosphites and triisopropyltrithiophosphites) were found to be transformed at the storage or upon recrystallization in polar solvents (CHCl3, CH3CN) into polymeric copper(I) clusters with Cu···Cu short contacts: [Cu2X2·L]n (where L = (EtS)2, (i‐PrS)2; X = Cl, Br). A completely different new polymeric complex was obtained by direct interaction of copper bromide with diethyl disulfide. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:542–546, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20274
Quantitative analysis of bonding in P4 clusters
Authors: Tsirelson V. G. , Tarasova N. P. , Bobrov M. F. , Smetannikov Yu. V.
Published: September 2006

Quantum‐topological analysis based on the nonempirical quantum‐chemical calculations of P4 clusters in the different electronic states has been done. Changes in the geometric parameters for the different electronic states of the equilibrium phosphorus clusters and structures with the breaking bonds are traced. The PP bonds are quantitatively described. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:572–578, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20279
Fluorinated benzazoles and benzazines
Authors: Nosova E. V. , Mochul'skaya N. N. , Kotovskaya S. K. , Lipunova G. N. , Charushin V. N.
Published: September 2006

The review surveys the recently obtained data on the synthesis of fluorinated benzazoles and benzazines. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:579–594, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20281
Desmoid tumor of the head and neck
Authors: Wang Cheng‐Ping , Chang Yih‐Leong , Ko Jenq‐Yuh , Cheng Chia‐Hsien , Yeh Chun‐Fong , Lou Pei‐Jen
Published: September 2006

Backgroud:

Desmoid tumors are rare benign tumors but have a tendency toward local recurrence after resection because of their infiltrative growth and frequent entrapment of vital structures in the head and neck region. We report 24 desmoid tumors of the head and neck and propose a reasonable approach in the management of such cases.

Methods:

Twenty‐four patients (9 male and 15 female; median age, 33 years; range, 0–66 years) with a desmoid tumor of the head and neck (neck, 15 patients; head, 9 patients) treated from 1990 to 2004 were retrospectively analyzed. The size ranged from 0.5 to 13 cm in diameter (mean, 3.6 cm). In the neck, 8 tumors were around the superficial layer of deep cervical fascia, whereas 4 tumors of the neck involved the prevertebral fascia and 2 involved brachial plexus.

Results:

Twenty patients received complete resection of the tumor, but the section margin was positive in 8 patients, of which 6 patients remained free of disease in a period of 13 to 105 months. Three patients, including 2 with positive section margin and 1 with negative margin, developed recurrences, which were successfully removed again. Two patients underwent partial resection of the tumor because of brachial plexus involvement. One of them achieved regression after postoperative radiotherapy and the other had spontaneous regression. The hypopharygneal tumor in a newborn had spontaneously complete regression, and tracheostomy was closed at the age of 6 years. One patient remained with stable disease for 14 months after biopsy of the tumor without excision.

Conclusion:

The overall prognosis is still good despite frequent incomplete resection. Surgical resection of the tumor with close observation is suggested even if the section margin is positive. If a desmoid tumor cannot be removed grossly, regression or arrested growth of the remaining tumor is expected. Radiotherapy might be reserved for a growing tumor. © 2006 Wiley Periodicals, Inc. Head Neck, 2006
Direct fluorescence visualization of clinically occult high‐risk oral premalignant disease using a simple hand‐held device
Authors: Poh Catherine F. , Ng Samson P. , Williams P. Michele , Zhang Lewei , Laronde Denise M. , Lane Pierre , MacAulay Calum , Rosin Miriam P.
Published: September 2006

Background

A considerable proportion of oral cancer and precancer is not clinically apparent and could contribute significantly to the late diagnosis and high mortality of oral cancer. A simple method to identify such occult change is needed.

Methods

Patients in the Oral Dysplasia Clinics at British Columbia are currently being examined with a simple hand‐held device that permits the direct visualization of alterations to autofluorescence in the oral cavity. Tissue showing loss of autofluorescence is biopsied.

Results

We present 3 representative cases in which occult lesions were identified with fluorescence visualization during longitudinal follow‐up, resulting in the diagnosis of a primary dysplasia in case 1, a second primary cancer in case 2, and cancer recurrence in case 3.

Conclusions

This is the first report of the diagnosis of occult oral disease using a simple noninvasive device. These early examples indicate the potential value of this technology to guide the management of patients with oral lesions, facilitating the detection of high‐risk changes not apparent with white‐light visualization. © 2006 Wiley Periodicals, Inc. Head Neck, 2006
Management of complicated head and neck wounds with vacuum‐assisted closure system
Authors: Andrews Brian T. , Smith Russell B. , Goldstein David P. , Funk Gerry F.
Published: September 2006

Background

The vacuum‐assisted closure system (V.A.C.), or negative pressure dressings, has been successfully used to manage complex wounds of the torso and extremities, but its role in the head and neck region has not been frequently described.

Methods

A retrospective study was performed. The V.A.C. system (Kinetic Concepts Inc., San Antonio, TX) was used at the University of Iowa Hospitals and Clinics for management of complicated head and neck wounds.

Results

The V.A.C. system was utilized at 13 sites for 12 patients. Nine subjects had exposed calvarium (4 had failed pedicled reconstructive flaps, 3 had ablative or Moh's defects, and 2 had traumatic scalping injuries) necessitating bony coverage. Three subjects had the V.A.C. system used as a bolster dressing placed over split‐thickness skin grafts (STSGs) used to reconstruct large defects of the face and skull, and 1 patient had a large soft tissue neck defect after radical surgical resection for necrotizing fascitis. One subject used the V.A.C. system for the management of 2 distinct wounds. All patients had successful healing of their wounds with the V.A.C. system without complication. All STSGs had 100% viability after 5 to 7 days of the V.A.C. system use as a bolster dressing.

Conclusion

This study demonstrates the V.A.C. system is a valuable tool in the management of complicated head and neck wounds. © 2006 Wiley Periodicals, Inc. Head Neck, 2006
Implication of “Down syndrome cell adhesion molecule” in the hippocampal neurogenesis of ischemic monkeys
Authors: Yamashima Tetsumori , Popivanova Boryana K. , Guo Jianzhong , Kotani Susumu , Wakayama Tomohiko , Iseki Shoichi , Sawamoto Kazunobu , Okano Hideyuki , Fujii Chifumi , Mukaida Naofumi , Tonchev Anton B.
Published: September 2006

Molecular signals regulating adult neurogenesis in primates are largely unknown. Here the authors used differential display to analyze gene expression changes that occur in dentate gyrus of adult monkeys after transient global cerebral ischemia. Among 14 genes upregulated, the authors focused on Down syndrome cell adhesion molecule (DSCAM) known to play crucial role during neuronal development, and characterized its expression pattern at the protein level. In contrast with approximately threefold upregulation of Dscam gene on days 5 and 7, immunoblotting and immunofluorescence analyses using specific antibodies showed a gradual decrease of DSCAM after ischemia until day 9 followed by recovery on day 15. In the control, immunofluorescence reactivity of DSCAM was detected in dentate gyrus granule cells and CA4 neurons but decreased after ischemia, being compatible with the immunoblotting data. However, in the subgranular zone, cerebral ischemia led to a marked increase of DSCAM‐positive cells on days 9 and 15. DSCAM upregulation was seen in two cell types: one is immature neurons positive for polysialylated neural cell adhesion molecule or βIII‐tubulin, while another is astrocytes positive for S100β. Young astrocytes were in intimate contact with newly generated neurons in the subgranular zone. These data suggest implication of DSCAM in the adult neurogenesis of primate hippocampus upregulated after ischemia. © 2006 Wiley‐Liss, Inc.
Investigating the in vivo activity of the DeaD protein using protein–protein interactions and the translational activity of structured chloramphenicol acetyltransferase mRNAs
Authors: Butland Gareth , Krogan Nevan J. , Xu Jianhua , Yang Wen‐Hong , Aoki Hiroyuki , Li Joyce S. , Krogan Naden , Menendez Javier , Cagney Gerard , Kiani Gholam C. , Jessulat Mathew G. , Datta Nira , Ivanov Ivan , AbouHaidar Mounir G. , Emili Andrew , Greenblatt Jack , Ganoza M. Clelia , Golshani Ashkan
Published: September 2006

Here, we report the use of an in vivo protein–protein interaction detection approach together with focused follow‐up experiments to study the function of the DeaD protein in Escherichia coli. In this method, functions are assigned to proteins based on the interactions they make with others in the living cell. The assigned functions are further confirmed using follow‐up experiments. The DeaD protein has been characterized in vitro as a putative prokaryotic factor required for the formation of translation initiation complexes on structured mRNAs. Although the RNA helicase activity of DeaD has been demonstrated in vitro, its in vivo activity remains controversial. Here, using a method called sequential peptide affinity (SPA) tagging, we show that DeaD interacts with certain ribosomal proteins as well as a series of other nucleic acid binding proteins. Focused follow‐up experiments provide evidence for the mRNA helicase activity of the DeaD protein complex during translation initiation. DeaD overexpression compensates for the reduction of the translation activity caused by a structure placed at the initiation region of a chloramphenicol acetyltransferase gene (cat) used as a reporter. Deletion of the deaD gene, encoding DeaD, abolishes the translation activity of the mRNA with an inhibitory structure at its initiation region. Increasing the growth temperature disrupts RNA secondary structures and bypasses the DeaD requirement. These observations suggest that DeaD is involved in destabilizing mRNA structures during translation initiation. This study also provides further confirmation that large‐scale protein–protein interaction data can be suitable to study protein functions in E. coli. J. Cell. Biochem. 100: 642–652, 2007. © 2006 Wiley‐Liss, Inc.
An iterative knowledge‐based scoring function to predict protein–ligand interactions: II. Validation of the scoring function
Authors: Huang Sheng‐You , Zou Xiaoqin
Published: September 2006

We have developed an iterative knowledge‐based scoring function (ITScore) to describe protein–ligand interactions. Here, we assess ITScore through extensive tests on native structure identification, binding affinity prediction, and virtual database screening. Specifically, ITScore was first applied to a test set of 100 protein–ligand complexes constructed by Wang et al. (J Med Chem 2003, 46, 2287), and compared with 14 other scoring functions. The results show that ITScore yielded a high success rate of 82% on identifying native‐like binding modes under the criterion of rmsd ≤2 Å for each top‐ranked ligand conformation. The success rate increased to 98% if the top five conformations were considered for each ligand. In the case of binding affinity prediction, ITScore also obtained a good correlation for this test set (R = 0.65). Next, ITScore was used to predict binding affinities of a second diverse test set of 77 protein–ligand complexes prepared by Muegge and Martin (J Med Chem 1999, 42, 791), and compared with four other widely used knowledge‐based scoring functions. ITScore yielded a high correlation of R2 = 0.65 (or R = 0.81) in the affinity prediction. Finally, enrichment tests were performed with ITScore against four target proteins using the compound databases constructed by Jacobsson et al. (J Med Chem 2003, 46, 5781). The results were compared with those of eight other scoring functions. ITScore yielded high enrichments in all four database screening tests. ITScore can be easily combined with the existing docking programs for the use of structure‐based drug design. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
Control of delocalization and structural changes by means of an electric field
Authors: Karafiloglou Padeleimon
Published: September 2006

The strength and, mainly, the direction of a static electric field can be used to control delocalization effects occurring in a non‐polar π‐system. The delocalization energy, the weights, and the probabilities of some local electronic structures, the behavior of electron pairs, and the electronic fluctuations are considered and examined in cis‐butadiene, used as model system. The effects of the electric field are detected and evaluated in the basis of natural orbital spaces appropriate to investigate the behavior of one‐ and poly‐electron distributions. The consequences of modifying the delocalization effects on structural changes are also investigated. Full geometry optimizations in both Hartree–Fock and MP2 levels show that the changes in bond lengths, guided by the changes of the behavior of the electronic assembly, can be controlled by means of the electric field. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
QM/QM study of the coverage effects on the adsorption of amino‐cyclopentene at the Si(100) surface
Authors: Santos Hugo R. R. , Ujaque Gregori , Ramos Maria J. , Gomes José A. N. F.
Published: September 2006

In this work, we have tested 30 different adsorption situations in several coverage scenarios for the 1‐amino‐3‐cyclopentene (ACP) molecule on the Si(100) surface. We have used a five‐spot testing zone inserted in the high‐level part of a quantum‐mechanical/quantum‐mechanical study performed in a big cluster. By defining several different scenarios, each one with a typical adsorption energy, we were able to understand in detail the process of surface functionalization. We are able to justify why the functionalization of this silicon surface achieves only a coverage of ˜0.5ML (half monolayer) and why the completely covered surface should be thermodynamically impossible to obtain. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
Analysis of the segmented contraction of basis functions using density matrix theory
Authors: Custodio Rogério , Gomes André Severo Pereira , Sensato Fabrício Ronil , Trevas Júlio Murilo dos Santos
Published: September 2006

A particular formulation based on density matrix (DM) theory at the Hartree‐Fock level of theory and the description of the atomic orbitals as integral transforms is introduced. This formulation leads to a continuous representation of the density matrices as functions of a generator coordinate and to the possibility of plotting either the continuous or discrete density matrices as functions of the exponents of primitive Gaussian basis functions. The analysis of these diagrams provides useful information allowing: (a) the determination of the most important primitives for a given orbital, (b) the core‐valence separation, and (c) support for the development of contracted basis sets by the segmented method. © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006
Spatial and acoustic pressure dependence of microbubble‐mediated gene delivery targeted using focused ultrasound
Authors: Rahim Ahad A. , Taylor Sarah L. , Bush Nigel L. , ter Haar Gail R. , Bamber Jeffrey C. , Porter Colin D.
Published: September 2006

Background

Ultrasound/microbubble‐mediated gene delivery has the potential to be targeted to tissue deep in the body by directing the ultrasound beam following vector administration. Application of this technology would be minimally invasive and benefit from the widespread clinical experience of using ultrasound and microbubble contrast agents. In this study we evaluate the targeting ability and spatial distribution of gene delivery using focused ultrasound.

Methods

Using a custom‐built exposure tank, Chinese hamster ovary cells in the presence of SonoVue® microbubbles and plasmid encoding β‐galactosidase were exposed to ultrasound in the focal plane of a 1 MHz transducer. Gene delivery and cell viability were subsequently assessed. Characterisation of the acoustic field and high‐resolution spatial analysis of transfection were used to examine the relationship between gene delivery efficiency and acoustic pressure.

Results

In contrast to that seen in the homogeneous field close to the transducer face, gene delivery in the focal plane was concentrated on the ultrasound beam axis. Above a minimum peak‐to‐peak value of 0.1 MPa, transfection efficiency increased as acoustic pressure increased towards the focus, reaching a maximum above 1 MPa. Delivery was microbubble‐dependent and cell viability was maintained.

Conclusions

Gene delivery can be targeted using focused ultrasound and microbubbles. Since delivery is dependent on acoustic pressure, the degree of targeting can be determined by appropriate transducer design to modify the ultrasound field. In contrast to other physical gene delivery approaches, the non‐invasive targeting ability of ultrasound makes this technology an attractive option for clinical gene therapy. Copyright © 2006 John Wiley & Sons, Ltd.
A peptide‐based immunoassay for antibodies against botulinum neurotoxin A
Authors: Atassi M. Zouhair , Dolimbek Behzod Z. , Deitiker Philip , Jankovic Joseph , Aoki K. Roger
Published: September 2006

Cervical dystonia (CD) is due to neck‐muscle spasms that cause pain and involuntary contractions resulting in abnormal neck movements and posture. Symptoms can be relieved by injecting the affected muscle with a botulinum neurotoxin (BoNT, usually type A or type B). The therapeutic benefits are impermanent and toxin injections need to be repeated every 3–6 months. In a very small percentage of patients (less with BoNT/A than with BoNT/B) the treatment elicits blocking anti‐toxin antibodies (Abs), which reduce or terminate the patient's responsiveness to further treatment. We have recently mapped (Dolimbek et al., 2006) the CD sera Ab‐binding profile using a panel of 60, 19‐residue peptides that encompassed the entire H chain sequence 449–1296 and overlapped consecutively by 5 residues. Abs in CD sera bound to one or more of the peptides N25, C10, C15, C20, and C31. This suggested the possibility that binding to these peptides could be used for assay of Abs in CD sera. Data analysis reported here found that Ab binding to these regions showed very significant deviations from the control responses. Of these four peptides, C10 showed the most significant level of separation between patient and control groups (p = 5 × 10−7) and the theoretical resolution (i.e., ability to distinguish CD patients from control, see full definition under ‘Statistical analysis’ in Methods), 84%, was about 4% higher than the least resolved response, C31 (p = 6 × 10−6, resolution 80%). Since the amounts of Abs bound to a given peptide varied with the patient and not all the patients necessarily recognized all four peptides, there was the possibility that binding to combinations of two or more peptides might give a better discriminatory capability. Using two peptides, C10 plus C31, the resolution improved to 87% (p = 4 × 10−8). These two peptides appeared to compliment each other and negate the lower resolution of C31. Combination of three peptides gave resolutions that ranged from 85 (N25 + C15 + C31; p = 2 × 10−7) to 88% (C10 + C15 + C31; p = 1 × 10−8). Finally, using the data of all four peptides, N25 + C10 + C15 + C31, gave a resolution of 86% (p = 1 × 10−7). Although these levels of resolution are somewhat lower than that obtained with whole BoNT/A (resolution 97%; p = 6 × 10−12), it may be concluded that the two‐peptide combination C10 + C31, or the three‐peptide combination C10 + C15 + C31 (affording resolutions of 87 and 88%, respectively) provide a good diagnostic, toxin‐free procedure for assay of total specific anti‐toxin Abs in BoNT/A‐treated CD patients. Copyright © 2006 John Wiley & Sons, Ltd.
Quantitative analysis of EO9 (apaziquone) and its metabolite EO5a in human plasma by high‐performance liquid chromatography under basic conditions coupled to electrospray tandem mass spectrometry
Authors: Vainchtein Liia D. , Rosing Hilde , Mirejovsky Dorla , Huynh Van , Lenaz Luigi , Hillebrand Michel J. X. , Schellens Jan H. M. , Beijnen Jos H.
Published: September 2006

A sensitive and specific LC‐MS/MS assay for the quantitative determination of EO9 and its metabolite EO5a is presented. A 200‐µl human plasma aliquot was spiked with a mixture of deuterated internal standards EO9‐d3 and EO5a‐d4 and extracted with 1.25 ml ethyl acetate. Dried extracts were reconstituted in 0.1 M ammonium acetate—methanol (7 : 3, v/v) and 25 µl‐volumes were injected into the HPLC system. Separation was achieved on a 150 × 2.1 mm C18 column using an alkaline eluent (1 mM ammonium hydroxide—methanol (gradient system)). Detection was performed by positive ion electrospray followed by tandem mass spectrometry. The assay quantifies a range from 5 to 2500 ng/ml for EO9 and from 10 to 2500 ng/ml EO5a using 200 µl of human plasma samples. Validation results demonstrate that EO9 and EO5a concentrations can be accurately and precisely quantified in human plasma. This assay will be used to support clinical pharmacologic studies with EO9. Copyright © 2006 John Wiley & Sons, Ltd.
Striatal specificity of gene expression dysregulation in Huntington's disease
Authors: Thomas Elizabeth A.
Published: September 2006

Huntington's disease (HD) is a progressive neurodegenerative disorder caused by an expanded CAG repeat region in exon 1 of the HD gene. This mutation results in the presence of an abnormally long polyglutamine tract in the encoded protein, huntingtin (htt). A major question in this field is how the mutant htt protein, which is expressed ubiquitously throughout the brain and body, causes severe neuropathologic changes predominantly in the striatum. The mechanisms accounting for this specificity are unknown. The role of transcriptional dysregulation in the pathophysiology of HD has gained much attention in recent years, however, this theory has been unable to explain the specificity of dysfunction and degeneration in HD. Microarray studies have showed hundreds of gene expression changes in mouse models of HD and in post‐mortem brain samples from HD subjects. Among the genes whose expression levels are preferentially altered are those that exhibit enriched expression in the striatum, which we have argued are the most relevant to disease pathology. These “striatal‐enriched” genes are associated with several systems previously implicated in HD pathology, especially disturbances in transcriptional processes and calcium homeostasis. Large‐scale changes in striatal gene expression in this manner would likely have particularly devastating effects to normal striatal function and could explain the specificity of striatal dysfunction and ultimate neurodegeneration observed in HD. © 2006 Wiley‐Liss, Inc.
Phosphorylation of glutamate receptors: A potential mechanism for the regulation of receptor function and psychostimulant action
Authors: Wang John Q. , Liu Xianyu , Zhang Guochi , Parelkar Nikhil K. , Arora Anish , Haines Michelle , Fibuch Eugene E. , Mao Limin
Published: September 2006

Ionotropic glutamate receptors,N‐methyl‐d‐aspartate receptors (NMDARs) and α‐amino‐3‐hydroxy‐5‐methylisoxazole‐4‐propionic acid receptors (AMPARs), are densely distributed in the mammalian brain and actively regulate a variety of cellular activities. Expression and function of these receptors are also under a tight regulation by many molecular mechanisms. Protein phosphorylation represents one of the important mechanisms for the posttranslational modulation of these receptors. Constitutive and regulatory phosphorylation occurs at distinct sites (serine, threonine, or tyrosine) on the intracellular C‐terminal domain of almost all subunits capable of assembling a functional channel. Several key protein kinases, such as protein kinase A, protein kinase C, Ca2+/calmodulin‐dependent protein kinases, and tyrosine kinases are involved in the site‐specific catalyzation and regulation of NMDAR and AMPAR phosphorylation. Through the phosphorylation mechanism, these protein kinases as well as protein phosphatases control biochemi cal properties (biosynthesis, delivery, and subunit assembling), subcellular distribution, and interactions of these receptors with various synaptic proteins, which ultimately modify the efficacy and strength of excitatory synapses containing NMDARs and AMPARs and many forms of synaptic plasticity. Emerging evidence shows that psychostimulants (cocaine and amphetamine) are among effective agents that profoundly alter the phosphorylation status of both receptors in striatal neurons in vivo. Thus, psychostimulants may modulate NMDAR and AMPAR function through the phosphorylation mechanism to shape the excitatory synaptic plasticity related to additive properties of drugs of abuse. © 2006 Wiley‐Liss, Inc.
Brain‐derived neurotrophic factor regulation of N‐methyl‐D‐aspartate receptor‐mediated synaptic currents in suprachiasmatic nucleus neurons
Authors: Kim Y.I. , Choi H.‐J. , Colwell C.S.
Published: September 2006

Light information reaches the suprachiasmatic nucleus (SCN) through a subpopulation of retinal ganglion cells. Previous work raises the possibility that brain‐derived neurotrophic factor (BDNF) and its high‐affinity receptor TrkB may be important as modulators of this excitatory input into the SCN. To test this possibility, we used whole‐cell patch‐clamp methods to measure excitatory currents in rat SCN neurons. These currents were evoked by electrical stimulation of the optic nerve. We found that the amplitude of the N‐methyl‐D‐aspartate (NMDA) component of the evoked excitatory postsynaptic currents (NMDA‐EPSC) was increased by application of BDNF. The neurotrophin also increased the magnitude of NMDA‐evoked currents in SCN neurons. The BDNF enhancement of the NMDA‐EPSC was blocked by treatment with the neurotrophin receptor antagonist K252a as well as treatment with the soluble form of the TrkB receptor engineered as an immunoadhesin (TrkB IgG). Finally, the BDNF enhancement was lost in brain slices treated with the NR2B antagonist ifenprodil. The results demonstrate that BDNF and TrkB receptors are important regulators of retinal glutamatergic synaptic transmission within the SCN. © 2006 Wiley‐Liss, Inc.
Effect of short‐term anaerobic conditions on the production of volatiles, activity of alcohol acetyltransferase and other quality traits of ripened bananas. Sumithra K Wendakoon. Yoshinori Ueda. Yoshihiro Imahori. Megumi Ishimaru. Journal of the Science of Food and Agriculture, 2006; 86: 1475–1480
Authors: Wendakoon Sumithra K , Ueda Yoshinori , Imahori Yoshihiro , Ishimaru Megumi
Published: September 2006

The original article to which this Erratum refers was published in Journal of the Science of Food and Agriculture, 2006; 86: 1475–1480.
A pilot investigation comparing low‐energy, double pass 1,450 nm laser treatment of acne to conventional single‐pass, high‐energy treatment
Authors: Bernstein Eric F.
Published: September 2006

Background and Objectives

Laser treatment using a 1,450 nm diode laser has been shown to improve acne and acne scarring. Its widespread adoption in younger populations has been significantly limited by discomfort.

Study Design/Materials and Methods

Six subjects with active papular acne were treated in a pilot study to determine parameters for a split‐face, double‐pass, low‐energy protocol of 1,450 nm laser treatment. Sides of the face were randomized to receive single‐pass, high‐energy treatment (13–14 J/cm2), or double‐pass, low energy treatment (8–11 J/cm2), for a total of four treatments delivered at monthly intervals. Acne counts and standardized, digital photograph were performed 2 months following the final treatment, and compared to pre‐treatment counts and photographs.

Results

Improvement was evaluated comparing pre‐ and post‐treatment photos and averaged 2.5 for the high‐energy, single‐pass side and 2.3 for the low‐energy, double‐pass side, using a 0 (worse) to 4 (max improvement) scale. Acne counts were reduced 78% on the high‐energy, single‐pass side and 67% on the low‐energy, double‐pass side. Pain ratings on a 1 (min) to 10 (max) scale averaged 5.6 (range 1–9) for the high‐energy, single‐pass side and 1.3 (range 1–2) for the low‐energy, double‐pass side.

Conclusions

Low‐energy, double‐pass 1,450 nm laser treatment effectively reduces acne counts 2 months post‐treatment, and dramatically reduces the pain associated with treatment. The treatment parameters used in this study have eliminated the need for anesthetic cream in daily practice. Lasers Surg. Med. 39:193–198, 2007. © 2007 Wiley‐Liss, Inc.
Erosion Behavior of Ionically Crosslinked Polyampholyte Gels Under DC Electric Fields
Authors: Zhao Yanbing , Chen Wanyu , Xia Jianjun , Liu Wei , Yang Yajiang , Xu Huibi , Yang Xiangliang
Published: September 2006

Summary: An ionic complex of anionic and cationic monomers was obtained when (N,N‐diethylamino)ethylmethacrylate (DEAEM) was protonated with acrylic acid (AAc). Through the free radical copolymerization of the ionic complex and acrylamide (AAm) in aqueous solution, a novel ionically crosslinked polyampholyte gel (poly(AAc‐DEAEM‐AAm), designated PADA) was prepared without chemical crosslinker. An investigation of swelling behavior indicated that PADA gels exhibited peculiar erosion phenomena under contact and non‐contact DC electric fields. Under contact DC electric fields, PADA gels of swollen equilibrium experienced a dual response to DC fields, i.e., swelling first and then erosion. This phenomenon has not been described elsewhere. In contrast to with the contact DC electric fields, PADA gels did not undergo a swelling process, but eroded completely within 20 min under non‐contact DC fields. The NaCl concentration in electrolyte solutions greatly influenced the swelling/eroding behavior of PADA gels because the ionic crosslinkages of PADA gels could be weakened and screened by salt ions. The combined effects of higher NaCl concentration and local pH change near the electrode under DC electric fields resulted in crosslinkages quickly dissociating into cationic and anionic groups. In this case, PADA gels did not experience the swelling process, but directly eroded. Moreover, the erosion rate of PADA gels was related to the voltage of the electric field. The swelling/eroding rate for the gels in contact with the cathode was faster than that for the gels in contact with the anode. This difference can be attributed to varying local pH near different electrodes.

The erosion process of PADA gels under non‐contact DC fields.

magnified image

The erosion process of PADA gels under non‐contact DC fields.
(Co)polymerisation Behaviour of Supported Metallocene Catalysts: Carrier Effect
Authors: Białek Marzena , Czaja Krystyna
Published: September 2006

Summary: The polymerisation and copolymerisation of ethylene with 1‐hexene over metallocene catalysts L2ZrCl2/MAO (L = Cp, n‐BuCp, t‐BuCp, i‐PrCp, Me5Cp) supported on different types of carriers (MgCl2(MeOH)6 or silica with CH3 surface groups obtained in the sol‐gel process) were studied. It was demonstrated that both the metallocene structure and the type of inorganic support affected catalyst activity and polymer properties such as melting point, molecular weight and molecular weight distribution. The metallocene structure also determined comonomer incorporation, both for homogeneous and supported catalytic systems. When a catalyst is anchored on a support, it becomes less effective at incorporating a comonomer into the polyethylene chain, and the type of the support material has no influence on that process. The type of carrier used does, however, have an influence on the molecular weight and molecular weight distribution of the product obtained. Most polymers and copolymers obtained with catalysts supported on an oxide carrier have higher molecular weights and broader molecular weight distributions than those produced by catalysts anchored on a magnesium compound.

Melting curves (obtained using the SSA method) of ethylene/1‐hexene copolymers synthesised with Cp2ZrCl2/MAO (A) and with the same catalyst supported on various carriers (B,C,D).

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Melting curves (obtained using the SSA method) of ethylene/1‐hexene copolymers synthesised with Cp2ZrCl2/MAO (A) and with the same catalyst supported on various carriers (B,C,D).
Fractionation and Characterisation of Propylene‐Ethylene Random Copolymers: Effect of the Comonomer on Crystallisation of Poly(propylene) in the γ‐Phase
Authors: Harding Gareth W. , van Reenen Albert J.
Published: September 2006

Summary: Three propylene‐ethylene random copolymers, of varying ethylene content, were fractionated using preparative TREF. The TREF fractions were subsequently analysed offline by CRYSTAF, DSC, 13C NMR spectroscopy, HT‐GPC, and WAXD. The effect of the ethylene comonomer on the crystallisability of the propylene was investigated, along with the effect of the comonomer on the type of crystal phase formed during the crystallisation. The results show that the comonomer inhibits the crystallisation of the copolymer and that as the ethylene content increases, the crystallisation and melting points decrease. It was also shown that the higher the ethylene content, the more of the γ‐phase crystal type is formed. The inter‐molecular distribution of the ethylene comonomer and stereo errors vary between the samples analysed, and this accounts for the relative differences in crystallisation behaviour of the samples.

13C NMR of propylene‐ethylene random copolymer.

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13C NMR of propylene‐ethylene random copolymer.
Enthalpy and Entropy Contributions to Solvent Quality and Inversions of Heat Effects with Polymer Concentration
Authors: Bercea Maria , Wolf Bernhard A.
Published: September 2006

Summary: Vapor pressures above the solutions of polystyrene in either cyclohexane (32–60 °C) or toluene (10–70 °C) have been measured by a combination of head space sampling and gas chromatography as a function of the volume fraction φ of the polymer. The thus obtained Flory‐Huggins interaction parameters χ (φ; T) were complemented by data for three other systems (tert‐butyl acetate/polystyrene, cyclohexane/poly(vinyl methyl ether), 2‐propanol/poly(butyl methacrylate)) reported in the literature and analyzed in terms of their enthalpy and entropy parts χH and χS. Furthermore these experimental findings were modeled by means of an approach splitting the mixing process conceptually into two parts and leading to the expression χ = χfc + χcr. The first step takes place at fixed conformation of the components and yields χfc; equilibrium is reached in the second step, during the conformational relaxation, contributing χcr. The results demonstrate that mixing can either be driven enthalpically or entropically. By contrast the conformational response acts in all cases towards homogeneous mixing. The inversion of heat effects observed for two of the five systems can be well modeled in terms of the composition dependence of the enthalpy parts of χfc and χcr.

Composition dependence of the enthalpy part, χH, of the Flory‐Huggins interaction parameter, and of the heat effects associated with the dilution in two steps.

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Composition dependence of the enthalpy part, χH, of the Flory‐Huggins interaction parameter, and of the heat effects associated with the dilution in two steps.
Phenolic Resin and Derived Carbon Hollow Spheres
Authors: Yang Mu , Ma Jin , Ding Shujiang , Meng Zhaokai , Liu Jinge , Zhao Tong , Mao Lanqun , Shi Yi , Jin Xigao , Lu Yunfeng , Yang Zhenzhong
Published: September 2006

Summary: Phenolic formaldehyde (PF) resins are attractive due to their excellent performances such as high temperature resistance, thermal abrasion, and high yield of carbon conversion. In this communication, PF resin‐based composite hollow spheres were fabricated by in situ favorable absorption and catalytic crosslinking of PF resin within sulfonated polystyrene gel layers of the hollow sphere templates at low temperature. The composite hollow spheres were achieved in one step, avoiding traditional removal of template cores. The intact shell was tuned from double‐layered to single‐layered. Carbon hollow spheres with porous shell were derived by carbonization of the PF composite hollow spheres. Metal/carbon composite hollow spheres were further synthesized by the incorporation of metal within the porous shell, which would be a promising material for catalysis.

TEM image of carbon double‐shelled hollow spheres after the PF composite spheres are calcined at 800 °C for 2 h in nitrogen.

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TEM image of carbon double‐shelled hollow spheres after the PF composite spheres are calcined at 800 °C for 2 h in nitrogen.
Novel Anionic Photoacid Generators (PAGs) and Corresponding PAG Bound Polymers
Authors: Wang Mingxing , Gonsalves Kenneth E. , Yueh Wang , Roberts Jeanette M.
Published: September 2006

Summary: A new series of functionalized anionic photoacid generators (PAGs), and corresponding polymers were prepared in moderate to good yield and characterized. The thermostability of PAG bound polymers was superior to PAG blend polymers. The fluorine‐free PAG bound or blend polymers exhibited higher stability than fluorine‐substituted PAG bound or blend polymers. Although the acid generating efficiency of PAG blend polymers was higher than that of PAG bound polymers, yet it is anticipated that PAG incorporated into the polymer main chain may improve acid diffusion compared with the PAG blend polymers. This was demonstrated by preliminary electron beam lithography (EBL) results: the fluorine PAG bound polymer resist HE‐F4‐MBS‐TPS gave 35 nm 1:1 L/S and showed better resolution than the blend sample HE Blend F4‐IBBS‐TPS. The PAG bound resist showed the capability for higher resolution, since 30 nm 2:1 L/S patterned. Based on these preliminary EBL results, the PAG bound polymer samples are anticipated to have a resolution capability for the 32 nm node for EUVL.

Design of microstructures for EUV lithography.

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Design of microstructures for EUV lithography.
Crystallization of Poly(ε‐caprolactone)/Poly(vinyl chloride) Miscible Blends Under Strain: The Role of Molecular Weight
Authors: Zhang Yubao , Prud'homme Robert E.
Published: September 2006

Summary: The effect of poly(ε‐caprolactone) (PCL) molecular weight on the orientation of crystalline PCL in miscible poly(ε‐caprolactone)/poly(vinyl chloride) (PCL/PVC) blends, melt crystallized under strain, has been studied by a combination of wide angle X‐ray diffraction (WAXD) and small angle X‐ray scattering (SAXS) studies. An unusual crystal orientation with the b‐axis parallel to the stretching direction was observed in miscible PCL/PVC blends with PCL of high molecular weight (>21 000). SAXS showed the presence of nanosize confined PCL in the PCL/PVC blends, which could be preserved at temperatures higher than the Tm of PCL but lower than the Tg of PVC. A mechanism based on the confinement of PCL crystal growth was proposed, which can explain the formation of b‐axis orientation in PCL/PVC blends crystallized under strain.

SAXS pattern of stretched PCL/PVC blend after annealing at 90 °C for 5 min.

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SAXS pattern of stretched PCL/PVC blend after annealing at 90 °C for 5 min.
Scale‐up of Microwave‐Assisted Polymerizations in Batch Mode: The Cationic Ring‐Opening Polymerization of 2‐Ethyl‐2‐oxazoline
Authors: Hoogenboom Richard , Paulus Renzo M. , Pilotti Åke , Schubert Ulrich S.
Published: September 2006

Summary: The use of microwave heating in polymer science is a rapidly growing field of research leading to faster and cleaner polymerization procedures. However, the majority of the investigations are performed at small scales (≈1 mL), which is far away from potential commercial applications of microwave‐assisted polymerizations. In addition, it has been shown in organic chemistry that microwave‐assisted reaction protocols can be directly scaled without the need for process optimization. In this contribution, we have investigated the direct scaling of microwave‐assisted polymerization procedures under pressure conditions using the cationic ring‐opening polymerization of 2‐ethyl‐2‐oxazoline as the model system. This polymerization was performed at scales ranging from 4.0 mmol (1 mL) to 1.0 mol (250 mL) in different microwave synthesizers covering both monomode and multimode devices.

Scale‐up of microwave‐assisted polymerizations in batch mode: the cationic ring‐opening polymerization of 2 ethyl‐2‐oxazoline.

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Scale‐up of microwave‐assisted polymerizations in batch mode: the cationic ring‐opening polymerization of 2 ethyl‐2‐oxazoline.
Effects of Annealing on the Migration Behavior of PA6/Clay Nanocomposites
Authors: Tang Yong , Lewin Menachem , Pearce Eli M.
Published: September 2006

Summary: Migration of clay to the surface of nylon 6‐organically modified clay is investigated. The effect of annealing time and temperature on the migration of the clay is reported. Attenuated total reflectance FT‐IR spectrometry, X‐ray diffraction, and high‐resolution electronic microscopy are used in this study. The results obtained indicate that migration occurs predominantly in the samples with exfoliated structure. Migration increases in the temperature range of 250–275 °C. A further increase in temperature decreases the extent of migration. Migration increases with time at 250 °C. Annealing in the presence of oxygen decreases migration. It is suggested that the extent of migration depends on the concentration of the surfactant and the polymer in the exfoliated particles.

High‐resolution electronic microscopy image of an exfoliated nylon‐6/clay sample in which migration has occurred.

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High‐resolution electronic microscopy image of an exfoliated nylon‐6/clay sample in which migration has occurred.
Mechanical Properties of the Nanometer Scale Precrystalline Order of a Poly(ethylene terephthalate)/Poly(ethylene naphthalate) Blend
Authors: Tranchida Davide , Kiflie Zebene , Piccarolo Stefano
Published: September 2006

Summary: Nanometer scale morphological order of macroscopically amorphous polyesters, obtained from the melt at moderate cooling rates, was observed in the past. The effect of such order on mechanical properties of a PET/PEN blend, evaluated by AFM nanoindentations, is reported in this study. Results show that nanoindentations conducted at relatively high load, with penetration depths of the order of 100 nm, confirm the information obtained from mechanical tests at micrometer scale, i.e., microhardness. On the other hand, true nanometer scale indentations (<40 nm) are seen to discriminate between the mechanical properties of the nanophases formed during solidification.

Statistical distribution of elastic moduli observed after 60 nanoindentations performed at 1 µN on each sample solidified at the cooling rates reported in the legend.

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Statistical distribution of elastic moduli observed after 60 nanoindentations performed at 1 µN on each sample solidified at the cooling rates reported in the legend.
99: are retailers best responding to rational consumers? Experimental evidence
Authors: Ruffle Bradley J. , Shtudiner Ze'ev
Published: September 2006

There exist numerous theories that attempt to explain the ubiquitous 99‐cent price ending. Most of these theories either do not hold up to inspection or posit irrational consumers who serve as a money pump for firms. We offer an experimental test of Basu's (Econ. Lett. 1997; 54:41–44) rational expectations equilibrium model in which consumers are fully rational. We find partial support for Basu's model. Convergence to the 99‐cent equilibrium is faster and more widespread when firms are able to observe the previous pricing decisions of others. By imitating the optimal 99‐cent price endings of rational firms, less rational firms display an ‘as if’ rationality. Copyright © 2006 John Wiley & Sons, Ltd.
Option pricing by students and professional traders: a behavioural investigation
Authors: Abbink Klaus , Rockenbach Bettina
Published: September 2006

We compare behaviour of students and professional traders from an influential German bank in an option pricing experiment. The arbitrage free price is independent of the probability distribution of the underlying asset. Students show a probability‐dependent option valuation, but learn to exploit more arbitrage with experience. The professional traders exhibit a less probability sensitive valuation, but their performance is lower than the students'. We explain this with a more intuitive and less analytic approach used by the professional traders, despite their superior knowledge of financial markets, due to the lack of known probability distributions in real markets. Copyright © 2006 John Wiley & Sons, Ltd.