bluuebunny/crossref_metadata_2025 huggingface dataset:
Matched block bootstrap for resampling multiseason hydrologic time series
Authors: Srinivas V. V. , Srinivasan K.
Published: May 2005

A nonparametric method for resampling multiseason hydrologic time series is presented. It is based on the idea of rank matching, for simulating univariate time series with strong and/or long‐range dependence. The rank matching rule suggests concatenating with higher likelihood those blocks that match at their ends. In the proposed method, termed ‘multiseason matched block bootstrap’, nonoverlapping within‐year blocks of hydrologic data (formed from the observed time series) are conditionally resampled using the rank matching rule. The effectiveness of the method in recovering various statistical attributes, including the dependence structure from finite samples generated from a known population, is demonstrated through a two‐level hypothetical Monte Carlo simulation experiment. The method offers enough flexibility to the modeller and is shown to be appropriate for modelling hydrologic data that display strong dependence, nonlinearity and/or multimodality in the time series depicting the hydrologic process. The method is shown to be more efficient than the nonparametric ‘k‐nearest neighbor bootstrap’ method in simulating the monthly streamflows that exhibit a complex dependence structure and bimodal marginal probability density. Even with short block sizes, this bootstrap method is able to predict the drought characteristics reasonably accurately. Copyright © 2005 John Wiley & Sons, Ltd.
Thermotolerance induced at a mild temperature of 40°C protects cells against heat shock‐induced apoptosis
Authors: Bettaieb Ahmed , Averill‐Bates Diana A.
Published: May 2005

Apoptosis constitutes a response of organisms to various physiological or pathological stimuli, and to different stresses. The ability of thermotolerance induced at a mild temperature of 40°C to protect against activation of the apoptotic cascade by heat shock was investigated. When Chinese hamster ovary and human adenocarcinoma cervical cells were pretreated at 40°C for 3 h, they were resistant to subsequent lethal heat shock at 43°C. Induction of thermotolerance at 40°C led to increased expresssion of heat shock proteins 27, 32, 72, and 90. Heat shock induced apoptotic events at the mitochondrial level, involving a decrease in membrane potential, translocation of Bax to mitochondria, and liberation of cytochrome c into the cytosol. These events were diminished in thermotolerant cells. Heat shock (42–45°C) caused activation of initiator caspase‐9 and effector caspases‐3, ‐6, and ‐7, relative to controls at 37°C. Activation of caspases was decreased in thermotolerant cells. Heat shock caused fragmentation of the caspase substrate, inhibitor of caspase‐activated DNase. Fragmentation was diminished in thermotolerant cells. Thermotolerance afforded protection against heat shock‐induced nuclear chromatin condensation, but not against necrosis. © 2005 Wiley‐Liss, Inc.
Developmental control via GATA factor interplay at chromatin domains
Authors: Bresnick Emery H. , Martowicz Melissa L. , Pal Saumen , Johnson Kirby D.
Published: May 2005

Despite the extraordinary task of packaging mammalian DNA within the constraints of a cell nucleus, individual genes assemble into cell type‐specific chromatin structures with high fidelity. This chromatin architecture is a crucial determinant of gene expression signatures that distinguish specific cell types. Whereas extensive progress has been made on defining biochemical and molecular mechanisms of chromatin modification and remodeling, many questions remain unanswered about how cell type‐specific chromatin domains assemble and are regulated. This mini‐review will discuss emerging studies on how interplay among members of the GATA family of transcription factors establishes and regulates chromatin domains. Dissecting mechanisms underlying the function of hematopoietic GATA factors has revealed fundamental insights into the control of blood cell development from hematopoietic stem cells and the etiology of pathological states in which hematopoiesis is perturbed. © 2005 Wiley‐Liss, Inc.
Curcumin prevents methylglyoxal‐induced oxidative stress and apoptosis in mouse embryonic stem cells and blastocysts
Authors: Hsuuw Yan‐Der , Chang Chen‐Kang , Chan Wen‐Hsiung , Yu Jau‐Song
Published: May 2005

Methylglyoxal (MG) is a reactive dicarbonyl compound endogenously produced mainly from glycolytic intermediates. Elevated MG levels in diabetes patients are believed to contribute to diabetic complications. MG is cytotoxic through induction of apoptosis. Curcumin, the yellow pigment of Curcuma longa, is known to have antioxidant and anti‐inflammatory properties. In the present study, we examined the effect of curcumin on apoptotic biochemical events caused by incubation of ESC‐B5 cells with MG. Curcumin inhibited the MG‐induced DNA fragmentation, caspase‐3 activation, cleavage of PARP, mitochondrial cytochrome c release, and JNK activation. Importantly, curcumin also inhibited the MG‐stimulated increase of reactive oxygen species (ROS) in these cells. In addition, we demonstrated that curcumin prevented the MG‐induced apoptosis of mouse blastocysts isolated from pregnant mice. Moreover, curcumin significantly reduced the MG‐mediated impairment of blastocyst development from mouse morulas. The results support the hypothesis that curcumin inhibits MG‐induced apoptosis in mouse ESC‐B5 cells and blastocysts by blocking ROS formation and subsequent apoptotic biochemical events. © 2005 Wiley‐Liss, Inc.
Inhibitory effects of digoxin and ouabain on aldosterone synthesis in human adrenocortical NCI‐H295 cells
Authors: Kau Mei‐Mei , Kan Shu‐Fen , Wang Jiing‐Rong , Wang Paulus S.
Published: May 2005

The present study was to investigate the effects and action mechanisms of digoxin and ouabain on steroidogenesis in human adrenocortical NCI‐H295 cells. Administration of digoxin or ouabain for 24 h decreased the basal and angiotensin II (Ang II)‐stimulated release of aldosterone by NCI‐H295 cells. The conversions of corticosterone (substrate of cytochrome P450 aldosterone synthase, P450c11AS) to aldosterone or deoxycortisol (substrate of cytochrome P450 11β‐hydroxylase, P450c11β) to cortisol were reduced by digoxin or ouabain. The basal and 22‐hydroxy‐cholesterol (a membrane‐permeable cholesterol, substrate of cytochrome P450 side‐chain cleavage enzyme, P450scc)‐stimulated pregnenolone release in mitochondria was inhibited by digoxin or ouabain. Digoxin or ouabain suppressed the basal and Ang II‐stimulated protein expression of steroidogenic acute regulatory (StAR) protein and P450scc. Incubation of digoxin or ouabain for 24 h reduced P450c11AS mRNA expression in NCI‐H295 cells. Digoxin or ouabain (10−6 M, 24 h)‐treated cells showed a lower resting intracellular Ca2+ concentration ([Ca2+]i) and an attenuated response of [Ca2+]i to Ang II. Since no significant cytotoxicity was observed at 10−6 M digoxin or ouabain, the digoxin‐ or ouabain‐induced decrease of aldosterone or cortisol release was not associated with cytotoxicity. These results demonstrate that digoxin or ouabain inhibits the aldosterone or cortisol release via reduction of P450c11AS or P450c11β and P450scc activities, inhibition of StAR and P450scc protein expression, suppression of P450c11AS mRNA expression, and attenuation of Ca2+ mobilization in NCI‐H295 cells. © 2005 Wiley‐Liss, Inc.
Interplay between NFBP and NF‐κB modulates tat activation of the LTR
Authors: Sweet Thersa , Sawaya Bassel E. , Khalili Kamel , Amini Shohreh
Published: May 2005

Interplay of the HIV‐1 regulatory protein, Tat, with several cellular factors plays an important role in transcriptional regulation of the viral promoter, the long terminal repeat (LTR). Special attention has been paid to NF‐κB, a family of inducible transcription factors, which interact with a specific DNA motif within the LTR. Here, we report on the physical and functional interaction of NFBP, a recently identified protein that interacts with the P65 subunit of NF‐κB, with HIV‐1 Tat. NFBP colocalizes with Tat in the nucleus and nucleoli, recognizes the amino acid residues 37 to 48 of Tat, and its interaction is modulated by RNA molecules. The interaction of NFBP with Tat modulates the synergism between Tat and P65 in activating LTR transcription. In the absence of the κB‐binding sites, NFBP augments the TAR‐dependent activation by Tat, yet it interferes with the synergistic effect of P65 and Tat on LTR transcription. © 2005 Wiley‐Liss, Inc.
Androgen receptor regulates Cdc6 in synchronized LNCaP cells progressing from G1 to S phase
Authors: Bai V. Uma , Cifuentes Eugenia , Menon Mani , Barrack Evelyn R. , Reddy G. Prem‐Veer
Published: May 2005

We have shown previously that androgen receptor (AR) activity is required for the progression of cells from G1 to S phase. In an attempt to elucidate the mechanism of androgen‐ and androgen‐receptor‐mediated proliferation of prostate cancer cells, we studied the effect of anti‐androgen bicalutamide (Casodex) on the expression of cell‐cycle regulatory genes in synchronized LNCaP cells progressing from G1 to S phase. LNCaP cells were synchronized by isoleucine‐deprivation. Expression of cell‐cycle regulatory genes in S phase control cells versus Casodex‐treated cells that fail to enter S phase was studied using a microarray containing cDNA probes for 111 cell‐cycle specific genes. RT‐PCR and Western‐blots were used to validate microarray data. Casodex blocked synchronized LNCaP cells from entering S phase. Microarrays revealed downregulation of eight genes in cells prevented from entering into S phase by Casodex. Of these eight genes, only Cdc6, cyclin A, and cyclin B were downregulated at both the mRNA and protein level in Casodex treated cells as compared to control cells. The mRNA and protein levels of Cdc6 increased as synchronized LNCaP cells progressed from G1 to S phase, and were attenuated in Casodex‐treated cells failed to enter S phase. Cyclins A and B were detected when cells entered S phase, but not when they were in G1 phase. Like Cdc6, the levels of both cyclins A and B were attenuated in Casodex‐treated cells. AR may play an important role in the onset of DNA synthesis in prostate cancer cells by regulating the expression and stability of Cdc6, which is critically required for the assembly of the pre‐replication complex(pre‐RC). © 2005 Wiley‐Liss, Inc.
Comparable evaluation of various commercially available aluminium‐based coagulants for the treatment of surface water and for the post‐treatment of urban wastewater
Authors: Zouboulis Anastasios I , Traskas Georgios
Published: May 2005

In this study the efficiency of various commercially‐available coagulants, ie alum and poly‐aluminium chlorides (PACls), for the treatment of surface (river) water, or for the post‐treatment of biologically pretreated urban wastewater were investigated. The different coagulants were comparatively evaluated, considering the removal of suspended solids (SS), natural organic matter (NOM), as well as the residual aluminium concentration, and the removal of phosphates (inorganic phosphorus), in the case of urban wastewater treatment. The dynamics of flocculation were also studied using a Photometric Dispersion Analyser (PDA) in order to compare the flocculation rates and the strength of different coagulant flocs. Finally, the optimum operational conditions, ie coagulant dosage, pH, temperature, duration and intensity of (initial) rapid‐mixing rate, were determined for the examined cases. It can be generally supported that PACl coagulants were superior to alum, as they presented higher SS and NOM removal, stronger and larger flocs, higher flocculation rates and lower residual aluminium concentration, which is a very important factor, especially for the treatment of surface water destinated for potable use. Copyright © 2005 Society of Chemical Industry
The synthesis of oxime reagents from natural and semi‐synthetic phenolic lipid and alkanoic acid resources for the solvent recovery of copper(II)
Authors: Tyman John HP , Iddenten Simon JA
Published: May 2005

In a study of the relationship between structure and efficiency towards recovery of copper(II) by chelation/solvent extraction, a series of homologous aldoximes has been synthesised from natural phenolic lipidic, and fatty lipidic renewable sources, for comparison with commercial reagents prepared from petrochemical sources. From cardanol, in technical cashew nut‐shell liquid, isoanacardic aldoxime, [2‐hydroxy‐4‐pentadec(en)yl]aldoxime, and from the natural phenolic lipid, anacardic acid, the isomer, 2‐hydoxy‐6‐pentadec(en)ylaldoxime, have been synthesised. A C11 analogue of anacardic aldoxime from Anacardium giganteum has been prepared. The isomeric n‐octyl aldoximes have been synthesised, the o‐ and p‐isomers from the readily available fatty acid n‐octanoic acid and the m‐isomer from cardanol. Related m‐aldoximes have been prepared from the ketonic intermediates methyl isoamyl and methyl amyl ketones. The solvent extraction properties for copper(II) of the synthesised aldoximes have been compared with those of a current commercial reagent, 2‐hydroxy‐5‐t‐nonylbenzaldoxime (Acorga 5100, Cytec), and two former extractants, 2‐hydroxy‐5‐t‐nonylacetophenone ketoxime (SME 529, Shell) and 2‐hydroxy‐5‐t‐nonylbenzophenone ketoxime (LIX 65N, Henkel). All the aldoximes possessed useful properties in extraction efficiency, notably the isoanacardic and the C8 aldoximes with the C8o‐isomer, 2‐hydroxy‐3‐n‐octylbenzaldoxime, exhibited optimal extraction, stripping and phase separation characteristics. Copyright © 2005 Society of Chemical Industry
Removal of tannins and polyhydroxy phenols by electro‐chemical techniques
Authors: Murugananthan M , Bhaskar Raju G , Prabhakar S
Published: May 2005

The removal of tannins and their basic molecules such as catechol, pyrogallol, phloroglucinol and resorcinol was studied by electro‐flotation and electro‐oxidation techniques. Iron rods and triple oxide (TaO2/RuO2/IrO2) coated titanium rods were used as electrodes for electro‐flotation and electro‐oxidation respectively. Interaction of tannins and polyhydroxy phenols with iron oxy‐hydroxide formed by anodic dissolution of iron was studied by UV‐Visible, FT‐IR and zeta‐potential measurements. GC–MS was used to identify the intermediate compounds formed during electro‐oxidation. Catechol, pyrogallol, phloroglucinol and resorcinol were found to be mineralized in the presence of triple oxide (TaO2/RuO2/IrO2) coated titanium electrodes. Catechol and pyrogallol were found to form insoluble organo‐metal complexes while resorcinol and phloroglucinol were found to adsorb on iron oxy‐hydroxide. The sludge thus formed was simultaneously separated from the aqueous phase by hydrogen bubbles. It was observed that the power consumption is relatively high for electro‐oxidation compared with electro‐flotation. The effects of pH and reaction time on their removal were also studied and the results are discussed. Copyright © 2005 Society of Chemical Industry
Evolvability of cell specification mechanisms
Authors: Félix Marie‐Anne , Barrière Antoine
Published: May 2005

The architecture of gene action during development is relevant to phenotypic evolution as it links genotype to morphological phenotype. Analysis of development at the level of cell fate specification mechanisms illuminates some of the properties of developmental evolution. In this article, we first review examples of evolutionary change in mechanisms of cell fate specification, with an emphasis on evolution in the dependence on inductive signaling and on evolution of the mechanisms that result in spatial asymmetries. We then focus on properties of development that bias possible phenotypic change and present how the distribution of phenotypes that are available by mutational change of the starting genotype can be experimentally tested by systematic mutagenesis. We finally discuss ways in which selection pressures on phenotypes can be inferred from a comparison of the phenotypic spectrum found on mutation with that found in the wild. J. Exp. Zool. (Mol. Dev. Evol.) 304B, 2005. © 2005 Wiley‐Liss, Inc.
Convenient synthesis of D‐threo‐[dichloroacetyl 1–14C] chloramphenicol
Authors: Sontakke C. V. , Patil S. P. , Unny V. K. P. , Sivaprasad N.
Published: May 2005

A convenient synthesis of chloramphenicol labelled with carbon‐14 in the dichloroacetyl group at the 1 position is described. It was prepared as part of a 4‐step sequence from [1‐14C] glycine and the product was purified by preparative HPLC. A radiochemical yield of 47% was obtained based on [1‐14C] glycine and the product had a specific activity of 0.47 mCi/mmol. The procedure can be employed for the synthesis of high specific activity [14C] chloramphenicol, labelled at 1, 2 or both the positions of dichloroacetyl group. Copyright © 2005 John Wiley & Sons, Ltd.
Radiosynthesis and in vivo study of [18F]1‐(2‐fluoroethyl)‐4‐[(4‐cyanophenoxy)methyl]piperidine: a promising new sigma‐1 receptor ligand
Authors: Zhao Jun , Chang Raymond , Carambot Patty , Waterhouse Rikki N.
Published: May 2005

The novel sigma‐1 receptor PET radiotracer [18F]1‐(2‐fluoroethyl)‐4‐[(4‐cyanophenoxy)methyl]piperidine ([18F]WLS1.002, [18F]‐2) was synthesized (n=6) by heating the corresponding N‐ethylmesylate precursor in an anhydrous acetonitrile solution containing [18F]fluoride, Kryptofix K222 and potassium carbonate for 15 min. Purification was accomplished by reverse‐phase HPLC methods, providing [18F]‐2 in 59±8% radiochemical yield (EOB), with specific activity of 2.89±0.80 Ci/µmol (EOS) and radiochemical purity of 98.3±2.1%. Rat biodistribution studies revealed relatively high uptake in many organs known to contain sigma‐1 receptors, including the lungs, kidney, heart, spleen, and brain. Good clearance from normal tissues was observed over time. Blocking studies (60 min) demonstrated high (>80%) specific binding of [18F]‐2 in the brain, with reduction also noted in other organs known to express these sites. Copyright © 2005 John Wiley & Sons, Ltd.
Improved synthesis of [18F]fluoromethyl tosylate, a convenient reagent for radiofluoromethylations
Authors: Neal Timothy R. , Apana Scott , Berridge Marc S.
Published: May 2005

The utility of [18F]fluoromethyl tosylate as an [18F]fluoromethylation reagent has been reexamined. The preparation of this potentially useful compound from the reaction of bis(tosyloxy) methane with 18F‐ was reported several years ago, but it had not found use as a labeling reagent. When the reported reaction of bis(tosyloxy) methane with 18F‐ was carried out, [18F]fluoromethyl tosylate was formed along with [18F]tosyl fluoride. The product ratio depended upon reaction conditions, with the yield of [18F]fluoromethyl tosylate usually in the range of 25–40%. Addition of a small amount of water to the reaction mixture resulted in a significant increase in the yield of [18F]fluoromethyl tosylate. Reaction conditions were defined that produced a yield of 71±6% of [18F]fluoromethyl tosylate (decay corrected). The product was conveniently purified by alumina chromatography. Reaction of [18F]fluoromethyl tosylate with the (des‐fluoromethyl) fluticasone propionate thioacid precursor produced [18F]fluticasone propionate in improved yield (16%, from fluoride in production‐scale runs) over other synthesis methods. Similarly, formation of [18F]choline, [18F]fluoromethionine and N‐([18F]fluoromethyl)spiperone from the reaction of [18F]fluoromethyl tosylate with corresponding precursors was examined. Copyright © 2005 John Wiley & Sons, Ltd.
Fast and efficient tritium labelling of the nonsteroidal anti‐inflammatory drugs naproxen, tolmetin, and zomepirac
Authors: Johansen Steen K. , Sørensen Lone , Martiny Lars
Published: May 2005

Fast and efficient tritium labelling of the nonsteroidal anti‐inflammatory drugs naproxen, tolmetin and zomepirac is reported. Naproxen along with its (R)‐enantiomer were labelled by catalytic tritium–halogen exchange of the corresponding 5‐bromo derivatives providing [3H]naproxen with a specific activity of 25.4 Ci/mmol. Tolmetin and zomepirac were labelled by the hydrogen isotope exchange reaction using Crabtree's catalyst. This provided [3H]tolmetin and [3H]zomepirac with specific activities of 80.8 and 64.3 Ci/mmol, respectively. All compounds were obtained in high radiochemical purity (>98%). Copyright © 2005 John Wiley & Sons, Ltd.
Synthesis of 1,1′ [11C]‐methylene‐di‐(2‐naphthol) ([11C]ST1859) for PET studies in humans
Authors: Langer Oliver , Krcal Andreas , Schmid Alexander , Abrahim Aiman , Minetti Patrizia , Celona Diana , Roeda Dirk , Dollé Frédéric , Kletter Kurt , Müller Markus
Published: May 2005

1,1′‐Methylene‐di‐(2‐naphthol) (ST1859), a candidate drug for the treatment of Alzheimer's disease, was radiolabelled with carbon‐11 with the aim to perform PET microdosing studies in humans. The radiosynthesis was automated in a commercial synthesis module (Nuclear Interface PET tracer synthesizer) and proceeded via reaction of [11C]formaldehyde with 2‐naphthol. [11C]formaldehyde was prepared by catalytic dehydrogenation of [11C]methanol (conversion yield: 48±11% (n = 19)) employing a recently developed silver‐containing ceramic catalyst. Starting from 69±3 GBq of [11C]carbon dioxide (n = 19), 4±1 GBq of [11C]ST1859 (decay‐corrected to the end of bombardment), readily formulated for intravenous administration, could be obtained in an average synthesis time of 38 min. The specific radioactivity of [11C]ST1859 at the end of synthesis exceeded 32 GBq/µmol. Copyright © 2005 John Wiley & Sons, Ltd.
Cockroach homologs of praying mantis peripheral auditory system components
Authors: Yager David D.
Published: May 2005

This study identifies the cuticular metathoracic structures in earless cockroaches that are the homologs to the peripheral auditory components in their sister taxon, praying mantids, and defines the nature of the cuticular transition from earless to eared in the Dictyoptera. The single, midline ear of mantids comprises an auditory chamber with complex walls that contain the tympana and chordotonal transduction elements. The corresponding area in cockroaches, between the furcasternum and coxae, has many socketed hairs arranged in discrete fields and the Nerve 7 chordotonal organ, the homolog of the mantis tympanal organ. The Nerve 7 chordotonal organ attaches at the apex of the lateral ventropleurite (LVp), which has the same shape and general structure as an auditory chamber wall. High‐speed video shows that when the coxa moves toward the midline, the LVp rotates medially to stimulate socketed hairs, and also moves like a triangular hinge giving the chordotonal organ maximal in–out stimulation. Formation of the mantis auditory chamber from the LVp and adjacent structures would involve only enlargement, a shift toward the midline, and a mild rotation. Almost all proprioceptive function would be lost, which may constitute the major cost of building and maintaining the mantis ear. Isolation from leg movement dictates the position of the mantis ear in the midline and the rigid frame, formed by the cuticular knobs, which protects the chordotonal organs. J. Morphol. © 2005 Wiley‐Liss, Inc.
Perioperative adjunctive treatment in the management of operable gastric cancer
Authors: Silberman Howard
Published: May 2005

Outcome in the management of clinically resectable gastric carcinoma has been disappointing, at least in Western populations, despite increasingly radical surgery and extensive experience with adjunctive perioperative treatment with innumerable single and combined modality regimens. The United States Intergroup Study, a prospective, randomized, controlled trial of adjuvant chemoradiation, demonstrated significant improvement in disease‐free and overall survival. Consequently, this regimen of postoperative fluoruracil plus leucovorin and locoregional radiation has been incorporated into current clinical practice. In hopes of further improving cure rates, many other regimens are under investigation, including the efficacy of neoadjuvant therapy alone, combined neoadjuvant and adjuvant therapy, and adjuvant therapy alone. In these clinical trials, therapeutic agents are prescribed alone or in multimodal regimens and include systemic chemotherapy, intraperitoneal (IP) chemotherapy with or without hyperthermia, intraoperative radiotherapy (IORT), and postoperative external beam irradiation. Several molecular markers have been identified, which seem to predict that a given tumor may be effective or resistant to a drug, raising the possibility of customized chemotherapy regimens. Preclinical studies suggest potential efficacy of angiogenesis inhibitors, monoclonal antibodies, and antisense agents. J. Surg. Oncol. 2005;90:174–186. © 2005 Wiley‐Liss, Inc.
Block Copolymers Under Shear Flow
Authors: Rychkov Igor
Published: May 2005

Summary:Microphase separation transition in block copolymer melts and solutions in equilibrium and under shear flow is reviewed. The non‐equilibrium molecular dynamics (NEMD) computer simulation methodology is presented in detail including the derivation of the SLLOD equations of motion, Gaussian thermostat, and operator‐splitting symplectic integrators. Results of our recent NEMD computer simulation studies of diblock copolymers in a selective solvent under shear flow are presented. Shear‐dependent structural, rheological, and microscopical properties are described. New phase transitions are discovered. The parallel‐perpendicular orientational transition in a weak‐strong flow is revealed. Theoretical approaches are reviewed including the Edwards Hamiltonian, Landau‐Ginzburg model, self‐consistent mean field theory, field‐theoretic simulation, as well as the time‐dependent Landau‐Ginzburg framework and its application to the studies of complex fluids.

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Efficient Simulations of Charged Colloidal Dispersions: A Density Functional Approach
Authors: Kim Kang , Yamamoto Ryoichi
Published: May 2005

Summary: A numerical method is presented for simulating charged colloidal dispersions in electrolyte solutions. Utilizing a smoothed profile for colloid‐solvent boundaries, efficient mesoscopic simulations are enabled for modeling dispersions of many colloidal particles exhibiting many‐body electrostatic interactions. The validity of the method was examined for simple colloid geometries, and the efficiency was demonstrated by calculating stable structures of two‐dimensional dispersions, which resulted in the formation of colloidal crystals.

Formation of a charged colloidal crystal.

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Formation of a charged colloidal crystal.
Transient Behavior and Gelation of Free Radical Polymerizations in Continuous Stirred Tank Reactors
Authors: Dias Rolando C. S. , Costa Mário Rui P. F. N.
Published: May 2005

Summary: Using the authors' previously developed method for the general kinetic analysis of non‐linear irreversible polymerizations, the simulation of free radical homogeneous polymerization systems with terminal branching and chain transfer to polymer has been carried out for continuous stirred tank reactors. Its improved accuracy on the numerical evaluation of generating functions has been exploited in order to perform their numerical inversion and chain length distributions could also be estimated with or without the presence of gel. A comparison with alternative techniques emphasizing the effect of their simplifying assumptions on the accuracy of calculations is also presented.

Predicted CLD before gelation (t = 1 h), after gelation (t = 15 h, steady state), and close to gel point for a free radical polymerization with transfer to polymer in a CSTR with τ = 60 min.

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Predicted CLD before gelation (t = 1 h), after gelation (t = 15 h, steady state), and close to gel point for a free radical polymerization with transfer to polymer in a CSTR with τ = 60 min.
Morphology of ABCD Tetrablock Copolymers Predicted by Self‐Consistent Field Theory
Authors: Wang Rong , Hu Jinglei , Jiang Zhibin , Zhou Dongshan
Published: May 2005

Summary: We studied the two‐dimensional (2D) microphase‐separated morphology of linear ABCD tetrablock copolymers by self‐consistent field theory. By varying the interaction parameters and the compositions, we found at least twelve structures, two of which – “four‐color” lamellae and “three‐color” core‐shell hexagonal phase – prove the existing experimental observations. These morphologies were discussed in correlation with the volume fraction of the components and the interaction parameters. A specific behavior of symmetrical tetrablock copolymers, i.e., fA = fD and fB = fC, is that the stable phases are lamellae, which is different from symmetrical ABC triblock copolymer having order‐to‐order transition. These results are helpful for the design of new block copolymer‐based nanomaterials.

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Kinetic Modeling of Thiol‐Ene Reactions with Both Step and Chain Growth Aspects
Authors: Okay Oguz , Bowman Christopher N.
Published: May 2005

Summary: A kinetic model is presented for thiol‐ene cross‐linking photopolymerizations including the allowance for chain growth reaction of the ene, i.e., homopolymerization. The kinetic model is based on a description of the average chain lengths derived from differential equations of the type of Smoluchowski coagulation equations. The method of moments was applied to obtain average properties of thiol‐ene reaction systems. The model predicts the molecular weight distribution of active and inactive species in the pre‐gel regime of thiol‐enes, as well as the gel points depending on the synthesis parameters. It is shown that, when no homopolymerization is allowed, the average molecular weights and the gel point conversion are given by the typical equations valid for the step‐growth polymerization. Increasing the extent of homopolymerization also increases the average molecular weights and shifts the gel point toward lower conversions and shorter reaction times. It is also shown that the ratio of thiyl radical propagation to the chain transfer kinetic parameter (kp1/ktr) affects the gelation time, tcr. Gelation occurs earlier as the kp1/ktr ratio is increased due to the predominant attack of thiyl radicals on the vinyl groups and formation of more stable carbon radicals. The gel point in thiol‐ene reactions is also found to be very sensitive to the extent of cyclization, particularly, if the monomer functionalities are low.

Number‐average chain length of carbon radicals $\bar X_1 \bullet$ (solid curves) and thiyl radicals $\bar X'_1 \bullet$ (dashed curves) plotted against the vinyl group conversion, xM, during thiol‐ene polymerization. Calculations were for six different kp/ktr ratios.

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Number‐average chain length of carbon radicals $\bar X_1 \bullet$ (solid curves) and thiyl radicals $\bar X'_1 \bullet$ (dashed curves) plotted against the vinyl group conversion, xM, during thiol‐ene polymerization. Calculations were for six different kp/ktr ratios.
Alpha‐synuclein and Parkinson's disease: Implications from the screening of more than 1,900 patients
Authors: Berg Daniela , Niwar Marc , Maass Sylvia , Zimprich Alexander , Möller J. Carsten , Wuellner Ullrich , Schmitz‐Hübsch Tanja , Klein Christine , Tan Eng‐King , Schöls Ludger , Marsh Laura , Dawson Ted M. , Janetzky Bernd , Müller Thomas , Woitalla Dirk , Kostic Vladimir , Pramstaller Peter P. , Oertel Wolfgang H. , Bauer Peter , Krueger Rejko , Gasser Thomas , Riess Olaf
Published: May 2005

Data on the frequency of α‐synuclein mutations in Parkinson's disease (PD) are limited. Screening the entire coding region in 1,921 PD patients with denaturing high performance liquid chromatography and subsequent sequencing we only detected silent mutations (g.2654A>G, g.10151G>A, and g.15986A>T) and the c.209G>A substitution corresponding to the p.A53T mutation. These results demonstrate that mutations in the α‐synuclein gene are rare and suggest that other factors contribute to α‐synuclein aggregation in the majority of PD patients. © 2005 Movement Disorder Society
Effect of repetitive TMS and fluoxetine on cognitive function in patients with Parkinson's disease and concurrent depression
Authors: Boggio Paulo S. , Fregni Felipe , Bermpohl Felix , Mansur Carlos G. , Rosa Moacyr , Rumi Demetrio O. , Barbosa Egberto R. , Odebrecht Rosa Marina , Pascual‐Leone Alvaro , Rigonatti Sérgio Paulo , Marcolin Marco A. , Araujo Silva Maria Teresa
Published: May 2005

Previous studies show that cognitive functions are more impaired in patients with Parkinson's disease (PD) and depression than in nondepressed PD patients. We compared the cognitive effects of two types of antidepressant treatments in PD patients: fluoxetine (20 mg/day) versus repetitive transcranial magnetic stimulation (rTMS, 15 Hz, 110% above motor threshold, 10 daily sessions) of the left dorsolateral prefrontal cortex. Twenty‐five patients with PD and depression were randomly assigned either to Group 1 (active rTMS and placebo medication) or to Group 2 (sham rTMS and fluoxetine). A neuropsychological battery was assessed by a rater blind to treatment arm at baseline and 2 and 8 weeks after treatment. Patients in both groups had a significant improvement of Stroop (colored words and interference card) and Hooper and Wisconsin (perseverative errors) test performances after both treatments. Furthermore, there were no adverse effects after either rTMS or fluoxetine in any neuropsychological test of the cognitive test battery. The results show that rTMS could improve some aspects of cognition in PD patients similar to that of fluoxetine. The mechanisms for this cognitive improvement are unclear, but it is in the context of mood improvement. © 2005 Movement Disorder Society
Simultaneous determination of 1H–1H and 1H–13C residual dipolar couplings in a chiral liquid crystal solvent using a natural abundance HSQC experiment
Authors: Marathias Vasilios M. , Goljer Igor , Bach II Alvin C.
Published: May 2005

A high‐resolution, phase‐sensitive, natural abundance F2‐coupled 1H–13C HSQC (F2HSQC) NMR experiment was developed to measure simultaneously both nDHH and 1DCH residual dipolar couplings (RDCs) of small molecules present in a chiral polypeptide liquid crystal solvent system composed of poly‐γ‐benzyl‐L‐glutamate (PBLG) in CDCl3. Because this is an indirect‐detection NMR experiment, the relatively small amount of sample (7.5 mg in this study) and short acquisition times (5 h) that are required make this HSQC experiment well suited for samples that are either limited in solubility or in quantity or require short analysis times. The F2HSQC experiment can be performed without any specialized equipment or sample modification and can enhance our ability to measure RDCs accurately and rapidly in polypeptide liquid crystal solvents. Copyright © 2005 John Wiley & Sons, Ltd.
Evidence for a role for anti‐Müllerian hormone in the suppression of follicle activation in mouse ovaries and bovine ovarian cortex grafted beneath the chick chorioallantoic membrane
Authors: Gigli I. , Cushman R.A. , Wahl C.M. , Fortune J.E.
Published: May 2005

The first critical transition in follicular development, the activation of primordial follicles to leave the pool of resting follicles and begin growth, is poorly understood, but it appears that the balance between inhibitory and stimulatory factors is important in regulating the exodus of follicles from the resting pool. There is evidence that anti‐Müllerian hormone (AMH; also known as MIS) inhibits follicle activation in mice, but whether it plays a similar role in non rodent species is not known. When pieces of bovine ovarian cortex, rich in primordial follicles, are cultured in serum‐free medium, most follicles initiate growth, but when cortical pieces are grafted beneath the chorioallantoic membrane (CAM) of chick embryos, follicle activation does not occur. Since embryonic chick gonads of both sexes produce and secrete high levels of AMH, the hypothesis that the AMH in the chick circulation inhibits follicle activation was tested. In Experiment 1, whole newborn mouse ovaries were grafted beneath the CAM (placed “in ovo”) or cultured in vitro for 8 days. In vitro (or after 8 days in vivo) follicles activated and proceeded to the primary or secondary stage, but activation was suppressed in ovo. This inhibition was reversed if ovaries were removed from beneath the CAM and cultured in vitro. In contrast, when ovaries from mice null mutant for the AMH type II receptor were CAM‐grafted in Experiment 2, follicle activation occurred in a similar fashion to activation in vitro. This finding strongly implicates AMH as the inhibitor of follicle activation in ovo. Since chick embryonic gonads are the source of circulating AMH, chicks were gonadectomized in Experiment 3, prior to grafting of pieces of bovine ovarian cortex beneath their CAMs. Bovine primordial follicles activated in the gonadectomized chicks, similar to the results for mice lacking the AMH type II receptor. Taken together these experiments provide strong evidence that AMH is the inhibitor of mouse follicle activation present in the circulation of embryonic chicks and provide indirect, and hence more tentative, evidence for AMH as an inhibitor of bovine follicle activation. © 2005 Wiley‐Liss, Inc.
c‐Kit immunophenotyping and metalloproteinase expression profiles of mast cells in interstitial lung diseases
Authors: Edwards Samuel T , Cruz Anthony C , Donnelly Samantha , Dazin Paul F , Schulman Edward S , Jones Kirk D , Wolters Paul J , Hoopes Charles , Dolganov Gregory M , Fang Kenneth C
Published: May 2005

Diverse interstitial lung diseases (ILD) demonstrate mesenchymal infiltration by an abundance of activated mast cells whose role in parenchymal fibrogenesis remains unclear. Since mast cells differentiate in a dynamic, tissue‐specific manner via signals transduced by c‐Kit receptor, we examined the effect of ILD microenvironments on c‐Kit expression and metalloproteinase phenotypes of mesenchymal mast cell populations. Immunohistochemical and flow cytometric analyses characterized surface expression of c‐Kit on mast cells in tissues obtained from patients with idiopathic pulmonary fibrosis, systemic sclerosis, sarcoidosis, and lymphangioleiomyomatosis, thus identifying a unique immunophenotype not shared by normal lung mast cells. Isolation of c‐Kit+/FcεRI+/CD34− mast cells via immunocytometric sorting of heterogeneous cell populations from mechanically disaggregated lung tissues permitted analysis of gene expression patterns by two‐step real‐time polymerase chain reaction. Transcriptional profiling identified expression of c‐Kit and the neutral serine proteases, tryptase and chymase, establishing the identity of sorted populations as mature mast cells. Mast cells harvested from ILD tissues demonstrated characteristic metalloproteinase phenotypes which included expression of matrix metalloproteinase (MMP)‐1 and a disintegrin and metalloproteinase (ADAM)‐9, ‐10, and ‐17. Immunohistochemical co‐localization guided by gene profiling data confirmed expression of chymase, MMP‐1, and ADAM‐17 protein in subpopulations of mast cells in remodelling interstitium. Gene profiling of harvested mast cells also showed increased transcript copy numbers for TNFα and CC chemokine receptor 2, which play critical roles in lung injury. We conclude that ILD microenvironments induce unique c‐Kit receptor and metalloproteinase mast cell phenotypes. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
IgVH mutations in blastoid mantle cell lymphoma characterize a subgroup with a tendency to more favourable clinical outcome
Authors: Cogliatti Sergio B , Bertoni Francesco , Zimmermann Dieter R , Henz Samuel , Diss Tim C , Ghielmini Michele , Schmid Ulrico
Published: May 2005

Mantle cell lymphoma (MCL) is associated with a very unfavourable clinical course. This is particularly true for mantle cell lymphoma of the blastoid subtype (MCL‐b). In order to define prognostic factors, we analysed the impact of immunoglobulin heavy chain variable (IgVH) gene somatic hypermutations on clinical outcome in a series of 21 cases of morphologically, phenotypically, and genotypically well‐characterized MCL‐b. Testing and estimation were performed using log‐rank statistics and displayed on Kaplan–Meier graphs. Thirteen of 21 cases of MCL‐b revealed a homology rate of ≥99% compared to IgVH germ‐line sequences in the databases and were scored as non‐mutated. Eight of 21 cases (38%) of MCL‐b were mutated. In MCL‐b the mutation frequency was usually low and the mutation pattern was only rarely antigen‐selected, in contrast to a control group of 11 cases with morphologically almost identical, but phenotypically and genotypically clearly distinguishable, diffuse large B cell lymphoma, derived, most likely, from germinal centre B cells. In our series of 21 MCL‐b, positive IgVH mutational status, irrespective of varying homology thresholds, had no statistically significant prognostic impact on event‐free or overall survival. However, mutated MCL‐b tended to present more frequently at an earlier stage and without bone marrow involvement and to show lower rates of relapse and death, resulting in a more favourable clinical outcome. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
High numbers of tumour‐infiltrating activated cytotoxic T lymphocytes, and frequent loss of HLA class I and II expression, are features of aggressive B cell lymphomas of the brain and testis
Authors: Riemersma Sietske A , Oudejans Joost J , Vonk Marcel J , Dreef Enno J , Prins Frans A , Jansen Patty M , Vermeer Maarten H , Blok Paul , Kibbelaar Robbie E , Muris Jettie JF , Schuuring Ed MD , Kluin Philip M
Published: May 2005

Loss of both HLA class I and class II expression in B cell lymphomas is a mechanism of escape from a cytotoxic T lymphocyte (CTL) immune response and will therefore give a strong selective survival advantage in tumours expressing strong immunogenic antigens. We investigated loss of HLA expression using specific antibodies on tissue sections from 254 B cell lymphomas originating from nodal and different extranodal sites in relation to numbers of tumour‐infiltrating T cells. Complete loss of HLA class I and II was observed in a minority of the nodal, stomach, and skin lymphomas but in the majority of the lymphomas originating from the testis and the CNS. Interestingly, relatively high percentages of activated CTLs were detected in both primary testicular and CNS lymphomas compared to lymphomas at other sites, with highest percentages in the testis (p < 0.0001). We conclude that loss of both HLA class I and II expression occurs very frequently in lymphomas originating from the testis and the CNS as compared to nodal and some other extranodal sites. The presence of high percentages of activated CTLs in the testicular and CNS lymphomas suggests that loss of HLA expression provides a strong growth advantage for lymphoma cells in these immune‐privileged sites. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
The transactivating isoforms of p63 are overexpressed in high‐grade follicular lymphomas independent of the occurrence of p63 gene amplification
Authors: Pruneri Giancarlo , Fabris Sonia , Dell'Orto Patrizia , Biasi Maria Olivia , Valentini Stefano , Del Curto Barbara , Laszlo Daniele , Cattaneo Laura , Fasani Roberta , Rossini Laura , Manzotti Michela , Bertolini Francesco , Martinelli Giovanni , Neri Antonino , Viale Giuseppe
Published: May 2005

p63 is a p53‐related gene mapping to 3q28 that codes for multiple mRNA transcripts with (TA‐p63) or without (ΔN‐p63) transactivating effects on genes that promote cell differentiation and apoptosis. We analysed p63 alterations by immunohistochemistry, quantitative real‐time RT‐PCR and FISH in a series of 45 follicular lymphomas (FL). None of the tumours showed immunoreactivity for the p40 antibody, which recognizes only the truncated isoforms of p63, or ΔN‐p63 mRNA expression. Immunoreactivity for the 4A4 antibody, which recognizes both the transactivating and the truncated p63 isoforms, was found in 5 ± 5.5%, 6.85 ± 4.88% and 33.2 ± 22.31% of grade I, II and III FL cells, respectively (p < 0.0001). Quantitative RT‐PCR analysis showed that all cases but one had TA‐p63 mRNA levels higher than non‐neoplastic lymphocytes, and that TA‐p63 mRNA expression correlated significantly (r = 0.9194, p < 0.0001) with the prevalence of p63 immunoreactivity. FISH extra signals for the p63 gene were found in seven (23.3%) of the 30 cases analysed (0/6 grade I, 2/15 grade II and 5/9 grade III; p = 0.01937). Further hybridizations showed a pattern highly suggestive of chromosome 3 polysomy in six cases. One of these cases also bore extra copies of the p63 and bcl‐6 genes. Co‐localization of p63 and IgH signals was found in one case. No association between the prevalence of p63 immunoreactivity and extra p63 gene signals was detectable when the cases were dichotomized according to a p63 immunoreactivity threshold of 10%. Our data suggest that TA‐p63 is overexpressed in high‐grade FL, possibly independent of the occurrence of gene abnormalities, and that it may be involved in the highly complex mechanism of regulation of apoptosis of FL cells. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
A comparative study of endothelial cell markers expressed in chronically inflamed human tissues: MECA‐79, Duffy antigen receptor for chemokines, von Willebrand factor, CD31, CD34, CD105 and CD146
Authors: Middleton Jim , Americh Laure , Gayon Regis , Julien Denis , Mansat Michel , Mansat Pierre , Anract Philippe , Cantagrel Alain , Cattan Pierre , Reimund Jean‐Marie , Aguilar Luc , Amalric Francois , Girard Jean‐Philippe
Published: May 2005

Endothelial cells play a central role in chronic inflammation: for example, they express adhesion molecules and present chemokines leading to enhanced leukocyte recruitment into tissues. Numerous markers of endothelial cells have been reported but there has been a lack of comparative data on their specificity. The present study compared the specificity of seven endothelial cell markers in the rheumatoid synovium and the colon of patients with Crohn's disease. These markers were: the sulphated epitope MECA‐79, the Duffy antigen receptor for chemokines (DARC), von Willebrand factor, CD31 (PECAM‐1), CD34, CD105 (endoglin) and CD146. MECA‐79, DARC and von Willebrand factor showed a specific endothelial cell distribution. MECA‐79, which recognizes sulphated ligands for leukocyte adhesion receptor L‐selectin (CD62L), was selective for a subset of venules in highly inflamed tissue and was present in rheumatoid but not control osteoarthritic synovia. DARC was also specific for venules but had a more widespread distribution than MECA‐79, and was present in rheumatoid and control synovia. The other markers all labelled endothelial cells in venules, arterioles and capillaries. However, they also localized to other cell types. For example, CD34 stained fibroblasts, CD146 was expressed by the pericytes and smooth muscle cells of vessel walls and CD31 and CD105 labelled a broad range of cell types. Copyright © 2005 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.