bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of predictive retention–activity models of butyrophenones by biopartitioning micellar chromatography
Authors: Martín‐Biosca Y. , Molero‐Monfort M. , Sagrado S. , Villanueva‐Camañas R. M. , Medina‐Hernández M. J.
Published: January 2005

The predictive and interpretative capability of quantitative chromatographic retention‐biological activity models is supported by the fact that in adequate experimental conditions the solute partitioning into the chromatographic system can emulate the solute partitioning into lipid bilayers of biological membranes, which is the basis of drug and metabolite uptake, passive transport across membranes and bioaccumulation. The use of retention data obtained in biopartitioning micellar chromatography (BMC) has been demonstrated to be helpful in describing the biological behaviour of different kinds of drugs. In this chromatographic system, polioxyethylene 23 lauryl ether Brij35 micellar mobile phases and C18 reversed stationary phase in adequate experimental conditions are used. The RP‐HPLC capacity factors of butyrophenones were determined using different Brij35 concentrations as micellar mobile phases. Relationships between seven biological activities of butyrophenones reported in bibliography and retention data were established and their predictive and interpretative ability evaluated. These relationships were significant between preclinical pharmacology and therapeutic efficacy parameters and the retention factors of butyrophenones (0.89 < R2 < 0.98). The results indicate that the retention of compounds in BMC is capable of describing and predicting in vitro the biological activities of butyrophenones. This approach can be very useful in the development of new neuroleptic drugs, avoiding the use of experimental animals. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

BMC

biopartitioning micellar chromatography

MLR

multiple linear regression

QRAR

quantitative retention–activity relationships

QSAR

quantitative structure–activity relationships

RMSEC

root mean square error of calibration

RMSECV

root mean square error of cross‐validation.
Amino acid sequence and D/L‐configuration determination methods for D‐amino acid‐containing peptides in living organisms
Authors: Iida Takayuki , Santa Tomofumi , Toriba Akira , Imai Kazuhiro
Published: January 2005

D‐amino acid‐containing peptides with biological activities have been isolated from invertebrates and amphibians, and partial racemization of amino acid residues in mammalian peptides associated with aging and diseases have been discussed. Here, we review the amino acid configuration determination methods in these peptides and recent progress of simultaneous determination method for sequence and configuration of amino acid residues. The applicability of C‐terminus sequence analysis and mass spectrometry to configuration determination of amino acids is also discussed. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

ATZ

aniliaothiazolinone

7beta;‐CD

β‐cylodextrin

FLEC

(+)‐1‐(9‐fluorenyl) ethyl chloroformate

NAC

N‐acetyl‐L‐cystein

OPA

O‐phthaldialdehyde

PITC

phenylisohydantoin

PTH

phenylthiohydantoin

TC

thiocarbamoyl

TH

thiohydantoin

TZ

thiazdinone.
Separation and quantification of paraquat and diquat in serum and urine by capillary electrophoresis
Authors: Vinner E. , Stievenart M. , Humbert L. , Mathieu D. , Lhermitte M.
Published: January 2005

The use of capillary electrophoresis (CE) for simultaneous qualitative and quantitative detection of paraquat (PQ) and diquat (DQ) in both serum and urine was investigated. The two herbicides were extracted from biological fluids with liquefied phenol. Serum required a deproteinization with chloroform and ammonium sulfate as pretreatment. The extracts were hydrodynamically injected and the complete separation was carried out in 10 min, using a capillary tube (75 µm i.d., 500 mm) of fused silica containing 50 mM phosphate buffer (pH 2.50) as the carrier. UV absorbance detection at 200 nm was performed by an on‐column detector. The analytes were characterized by their respective migration times. Analytical recoveries were 52.6% for PQ and 62.6% for DQ in serum, and 71.4% and 59.3%, respectively, in urine. The linearity was studied up to 4 mg/L and the limits of detection (LODs) were better than 5 pg/mL in serum or urine. The CE method described was applied to the characterization of two lethal poisonings and results were related. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

DQ

diquat

LOD

limit of detection

LOQ

limit of quantification

PQ

paraquat.
Separation of strength and selectivity of mobile phase by spectral mapping technique
Authors: Forgács Esther , Cserháti Tibor , Balogh Sándor , Kaliszan Roman , Haber Peter , Nasal Anton
Published: January 2005

The retention behaviour of seven monotetrazolium and nine ditetrazolium salts was studied in seven different mobile phases on alumina and impregnated alumina stationary phases. The strength and selectivity of the components of mobile phases were separately calculated by the spectral mapping technique. It was established that tetrahydrofuran (THF) has the highest solvent strength while the differences among ethanol, 1‐propanol, 2‐propanol and dioxane were relatively low. The selectivity of THF was also considerably different from those of other solvents. Hydrophobicity and electronic parameters were equally involved in the retention strength and selectivity of tetrazolium salts, indicating the mixed character of their interaction with the alumina stationary phase. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

SPM

spectral mapping technique

THF

tetrahydrofuran
Sensitive determination of bisphenol A and alkylphenols by high performance liquid chromatography with pre‐column derivatization with 2‐(4‐carboxyphenyl)‐5,6‐dimethylbenzimidazole
Authors: Katayama Masatoki , Sasaki Tadahiro , Matsuda Yoshifumi , Kaneko Satoru , Iwamoto Teruaki , Tanaka Masami
Published: January 2005

A new and sensitive high‐performance chromatographic method for the determination of bisphenol A and 8 alkylphenols with fluorescence detection is reported. Each phenol was derivatized by reaction with 2‐(4‐carboxyphenyl)‐5,6‐dimethylbenzimidazole at 40°C for 60 min. The fluorescence derivatives were separated on a Wakosil 5C18 column (4.0 i.d. × 300 mm, 5 µm) with methanol:water (10:90) as mobile phase (detection wavelength: λex 336 nm, λem 440 nm). The detection limits were in the range of 0.1–10.0 pg/mL in serum. The calibration graphs were linear to 1.0 µg/mL. The relative standard deviations were 7.2–8.9%, respectively. The proposed method was applied to the determination of bisphenol A in mother and infant rat serum. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

CDB

2‐(4‐carboxyphenyl)‐5,6‐dimethylbenzimidazole

ED

endocrine discriptor

IDC

1‐isopropyl‐3‐(3‐dimethylaminopropyl) carbodiimide perchlorate.
Immunoaffinity isolation of CEACAM1 on hydrazide‐derivatized cellulose with immobilized monoclonal anti‐CEA antibody
Authors: Muchová L. , Jirsa M. , Kuroki M. , Dudková L. , Beneš M. J. , Mareček Z. , Šmíd F.
Published: January 2005

Carcinoembryonic cell adhesion molecule 1 (CEACAM1) is a human membrane glycoprotein belonging to the carcinoembryonic antigen (CEA) family and to the immunoglobulin superfamily. It is expressed in apical membranes of many epithelial cells in gastrointestinal and urogenital tract and also in granulocytes and lymphocytes, and its biological effect in human tissues has recently been discussed in literature. The purpose of this study was to isolate CEACAM1 glycoprotein from bile and characterize its purity and recovery which has not been described before. Affinity chromatography of CEACAM1 on hydrazide‐activated cellulose with immobilized monoclonal anti‐CEA F34‐187 antibody is described. The immunoglobulin carbohydrate moiety was oxidized by periodate and then bound to hydrazide‐activated matrix. Crude protein fraction from bile was applied on the affinity column and after extensive washing of non‐bound proteins CEACAM1 was eluted with 6 M guanidine–HCl. A single immunopositive 85 kDa band was detected on Western blots with anti‐CEA antibody after SDS–PAGE. We found out that CEACAM1 was not stainable with any common method of protein staining and the only non‐specific method which could detect the 85 kDa band was a lectin staining. Copyright © 2001 John Wiley & Sons, Ltd.

Abbreviations used:

BGP1

biliary glycoprotein 1

CEA

carcinoembryonic antigen

CEACAM1

carcinoembryonic cell adhesion molecule 1

PBS

phosphate buffered saline
Determination of amphetamine and its metabolite p‐hydroxyamphetamine in rat urine by reversed‐phase high‐performance liquid chromatography after dabsyl derivatization
Authors: Soares Maria Elisa , Carvalho Félix , de Lourdes Bastos Maria
Published: January 2005

The consumption of amphetamine is illicit and controlled due to both the elicited behavioural deviations and the toxicity effects reported in abusers. Thus, amphetamine levels in biological samples must be monitored in several clinical and forensic circumstances. In spite of the interspecies differences in the preferred route of biotransformation, benzylmethylketone, benzoic acid and 4‐hydroxyamphetamine are the principal metabolites of amphetamine. However, the clinical and forensic studies are focused in the parent compound and in 4‐hydroxyamphetamine since benzylmethylketone is a minor metabolite in human and benzoic acid is also an endogenous compound. In the present study amphetamine and its metabolite, 4‐hydroxyamphetamine, are quantified in urine by HPLC after derivatization with 4‐dimethylaminoazobenzene‐4′‐sulfonyl chloride (dabsyl chloride). This derivatization procedure transforms amphetamine and its hydroxylated metabolite in compounds with similar lipofilicity, enabling their quantitative and simultaneous extraction with an organic solvent. The precision of the HPLC technique was 7.3 and 10.0% for amphetamine and 4‐hydroxyamphetamine derivatives, respectively. For the overall procedure, including enzymatic hydrolysis, derivatization and extraction of the derivatives, the obtained values were 9.3 and 6.2%. Recoveries obtained from spiked urines for amphetamine and 4‐hydroxyamphetamine were better than 97% and 94% (mean value), respectively. The detection limits of the method was 10 ng for both compounds. The principal advantages of the present proposed method are the stability of the dabsyl derivatives at room temperature and the detection carried out in the visible region, reducing the interferences detected. Copyright © 2001 John Wiley & Sons, Ltd.
Assessment of “juvenile psychopathy” and its association with violence: a critical review*
Authors: Edens John F. , Skeem Jennifer L. , Cruise Keith R. , Cauffman Elizabeth
Published: January 2005

Interest in the construct of psychopathy as it applies to children and adolescents has become an area of considerable research interest in the past 5–10 years, in part due to the clinical utility of psychopathy as a predictor of violence among adult offenders. Despite interest in “juvenile psychopathy” in general and its relationship to violence in particular, relatively few studies specifically have examined whether operationalizations of this construct among children and adolescents predict various forms of aggression. This article critically reviews this literature, as well as controversies regarding the assessment of adult psychopathic “traits” among juveniles. Existing evidence indicates a moderate association between measures of psychopathy and various forms of aggression, suggesting that this construct may be relevant for purposes of short‐term risk appraisal and management among juveniles. However, due to the enormous developmental changes that occur during adolescence and the absence of longitudinal research on the stability of this construct (and its association with violence), we conclude that reliance on psychopathy measures to make decisions regarding long‐term placements for juveniles is contraindicated at this time. Copyright © 2001 John Wiley & Sons, Ltd.
Residential mental health assessment within Dutch criminal cases: a discussion
Authors: van der Leij Jan Bas J. , Jackson Janet L. , Malsch Marijke , Nijboer Johannes F.
Published: January 2005

In Dutch criminal cases in which doubts arise about the defendant's mental health, a forensic assessment will be requested. This is provided either by the multidisciplinary staff of residential clinics who conduct forensic evaluations for the court, or by mental health professionals contracted on a part‐time basis by district courts. This article discusses the procedures applied in such cases as well as the relevant legal provisions. It focuses particularly on the clinical observation, evaluation, and reporting that is carried out over a number of weeks in the residential setting of the Pieter Baan Centrum. Specific attention is paid to procedures applied in this clinic. It is suggested that Dutch procedures for the use of mental health expertise can best be characterized by three aspects: multidisciplinary observation and reporting, the use of a sliding scale for indicating degree of responsibility, and, finally, the involvement and payment of experts by the state as such, rather than by the prosecution and/or the defense. Copyright © 2001 John Wiley & Sons, Ltd.
Shifted factor analysis—Part I: Models and properties
Authors: Harshman Richard A. , Hong Sungjin , Lundy Margaret E.
Published: January 2005

The factor model is modified to deal with the problem of factor shifts. This problem arises with sequential data (e.g. time series, spectra, digitized images) if the profiles of the latent factors shift position up or down the sequence of measurements: such shifts disturb multilinearity and so standard factor/component models no longer apply. To deal with this, we modify the model(s) to include explicit mathematical representation of any factor shifts present in a data set; in this way the model can both adjust for the shifts and describe/recover their patterns. Shifted factor versions of both two‐ and three (or higher)‐way factor models are developed. The results of applying them to synthetic data support the theoretical argument that these models have stronger uniqueness properties; they can provide unique solutions in both two‐way and three‐way cases where equivalent non‐shifted versions are under‐identified. For uniqueness to hold, however, the factors must shift independently; two or more factors that show the same pattern of shifts will not be uniquely resolved if not already uniquely determined. Another important restriction is that the models, in their current form, do not work well when the shifts are accompanied by substantial changes in factor profile shape. Three‐way factor models such as Parafac, and shifted factor models such as described here, may be just two of many ways that factor analysis can incorporate additional information to make the parameters identifiable. Copyright © 2003 John Wiley & Sons, Ltd.
Multivariate calibration of analytical signals by WILMA (wavelet interface to linear modelling analysis)
Authors: Cocchi Marina , Seeber Renato , Ulrici Alessandro
Published: January 2005

A novel algorithm based on coupling of the fast wavelet transform (FWT) with MLR and PLS regression techniques for the selection of optimal regression models between matrices of signals and response variables is presented: wavelet interface to linear modelling analysis (WILMA). The algorithm decomposes each signal into the FWT domain and then, by means of proper criteria, selects the wavelet coefficients that give the best regression models, as evaluated by the leave‐one‐out cross‐validation criterion. The predictive ability of the regression model is then checked by means of external test sets. Moreover, the signals are reconstructed back in the original domain using only the selected wavelet coefficients, to allow for chemical interpretation of the results. The algorithm was tested on different literature data sets: two near‐infrared data sets from Kalivas, on which the performances of many calibration algorithms have already been tested, and a data set consisting of lead and thallium mixtures measured by differential pulse anodic stripping voltammetry and giving seriously overlapped responses. Good results were obtained for all the studied data sets; in particular, for the data sets from Kalivas the WILMA models showed improved predictive capability. Copyright © 2003 John Wiley & Sons, Ltd.
Photoreaction of [Ru(hat)2phen]2+ with Guanosine‐5′‐Monophosphate and DNA: Formation of New Types of Photoadducts
Authors: Blasius Romain , Nierengarten Hélène , Luhmer Michel , Constant Jean‐François , Defrancq Eric , Dumy Pascal , van Dorsselaer Alain , Moucheron Cécile , Kirsch‐DeMesmaeker Andrée
Published: January 2005

[Ru(hat)2phen]2+ (HAT=1,4,5,8,9,12‐hexaazatriphenylene, phen=1,10‐phenanthroline) interacts with a good affinity with polynucleotides and DNA by intercalation, despite the presence of a second voluminous ancillary HAT ligand. It photoreacts with guanosine‐5′‐monophosphate (GMP). From HPLC, ESMS and NMR analyses, it can be concluded that this complex forms photoadducts with GMP. In contrast to the photoadducts isolated with Ru–TAP complexes (TAP=1,4,5,8‐tetraazaphenanthrene), the photoadducts with [Ru(hat)2phen]2+ contain a covalent link between the oxygen atom of the guanine unit and a HAT ligand. Formation of oxidised photoadducts and compounds resulting from the addition of two GMP entities to the complex are also detected as side products. In the presence of oligo‐ and polynucleotides, [Ru(hat)2phen]2+ yields photoadducts when guanine bases are present.
Aldol Additions of Dihydroxyacetone Phosphate to N‐Cbz‐Amino Aldehydes Catalyzed by L‐Fuculose‐1‐Phosphate Aldolase in Emulsion Systems: Inversion of Stereoselectivity as a Function of the Acceptor Aldehyde
Authors: Espelt Laia , Bujons Jordi , Parella Teodor , Calveras Jordi , Joglar Jesús , Delgado Antonio , Clapés Pere
Published: January 2005

The potential of L‐fuculose‐1‐phosphate aldolase (FucA) as a catalyst for the asymmetric aldol addition of dihydroxyacetone phosphate (DHAP) to N‐protected amino aldehydes has been investigated. First, the reaction was studied in both emulsion systems and conventional dimethylformamide (DMF)/H2O (1:4 v/v) mixtures. At 100 mM DHAP, compared with the reactions in the DMF/H2O (1:4) mixture, the use of emulsion systems led to two‐ to three‐fold improvements in the conversions of the FucA‐catalyzed reactions. The N‐protected aminopolyols thus obtained were converted to iminocyclitols by reductive amination with Pd/C. This reaction was highly diastereoselective with the exception of the reaction of the aldol adduct formed from (S)‐N‐Cbz‐alaninal, which gave a 55:45 mixture of both epimers. From the stereochemical analysis of the resulting iminocyclitols, it was concluded that the stereoselectivity of the FucA‐catalyzed reaction depended upon the structure of the N‐Cbz‐amino aldehyde acceptor. Whereas the enzymatic aldol reaction with both enantiomers of N‐Cbz‐alaninal exclusively gave the expected 3R,4R configuration, the stereochemistry at the C‐4 position of the major aldol adducts produced in the reactions with N‐Cbz‐glycinal and N‐Cbz‐3‐aminopropanal was inverted to the 3R,4S configuration. The study of the FucA‐catalyzed addition of DHAP to phenylacetaldehyde and benzyloxyacetaldehyde revealed that the 4R product was kinetically favored, but rapidly disappeared in favor of the 4S diastereoisomer. Computational models were generated for the situations before and after CC bond formation in the active site of FucA. Moreover, the lowest‐energy conformations of each pair of the resulting epimeric adducts were determined. The data show that the products with a 3R,4S configuration were thermodynamically more stable and, therefore, the major products formed, in agreement with the experimental results.
α‐Helical Polypeptide Microcapsules Formed by Emulsion‐Templated Self‐Assembly
Authors: Morikawa Masa‐aki , Yoshihara Masakuni , Endo Takeshi , Kimizuka Nobuo
Published: January 2005

α‐Helical peptide microcapsules were prepared by the emulsion‐templated self‐assembly of amphiphilic poly(γ‐benzyl L‐glutamate)s (PBLG) 1. By mixing solutions of 1 in dichloromethane (in the form of a sodium salt) with water, oil‐in‐water emulsions were obtained. Spontaneous stripping of the dichloromethane phase caused a decrease in the diameter of the microdroplets and finally stable microcapsules formed. The microcapsules contain an inner aqueous phase as observed by confocal laser scanning microscopy (CLSM). Binding of hydrophobic pyrene molecules to the polypeptide shell was also demonstrated. The present polypeptide microcapsules are stable even after drying in air and they would serve as supramolecular vehicles for both hydrophobic and water‐soluble molecules.
Contrasting Behavior in Azide Pyrolyses: An Investigation of the Thermal Decompositions of Methyl Azidoformate, Ethyl Azidoformate and 2‐Azido‐N, N‐dimethylacetamide by Ultraviolet Photoelectron Spectroscopy and Matrix Isolation Infrared Spectroscopy
Authors: Dyke John M. , Levita Giacomo , Morris Alan , Ogden J. Steven , Dias Antonio A. , Algarra Manolo , Santos Jose P. , Costa Maria L. , Rodrigues Paula , Andrade Marta M. , Barros M. Teresa
Published: January 2005

The thermal decompositions of methyl azidoformate (N3COOMe), ethyl azidoformate (N3COOEt) and 2‐azido‐N,N‐dimethylacetamide (N3CH2CONMe2) have been studied by matrix isolation infrared spectroscopy and real‐time ultraviolet photoelectron spectroscopy. N2 appears as an initial pyrolysis product in all systems, and the principal interest lies in the fate of the accompanying organic fragment. For methyl azidoformate, four accompanying products were observed: HNCO, H2CO, CH2NH and CO2, and these are believed to arise as a result of two competing decomposition routes of a four‐membered cyclic intermediate. Ethyl azidoformate pyrolysis yields four corresponding products: HNCO, MeCHO, MeCHNH and CO2, together with the five‐membered‐ring compound 2‐oxazolidone. In contrast, the initial pyrolysis of 2‐azido‐N,N‐dimethyl acetamide, yields the novel imine intermediate Me2NCOCHNH, which subsequently decomposes into dimethyl formamide (HCONMe2), CO, Me2NH and HCN. This intermediate was detected by matrix isolation IR spectroscopy, and its identity confirmed both by a molecular orbital calculation of its IR spectrum, and by the temperature dependence and distribution of products in the PES and IR studies. Mechanisms are proposed for the formation and decomposition of all the products observed in these three systems, based on the experimental evidence and the results of supporting molecular orbital calculations.
High Surface Area, Mesoporous, Glassy Alumina with a Controllable Pore Size by Nanocasting from Carbon Aerogels
Authors: Li Wen‐Cui , Lu An‐Hui , Schmidt Wolfgang , Schüth Ferdi
Published: January 2005

A strategy to synthesize amorphous, mesoporous alumina by nanocasting has been developed, involving carbon aerogel as a hard template and aluminum nitrate solution as an alumina precursor. The alumina generated exhibits small, transparent granules with a 3–6 mm diameter and has inherited the three‐dimensional network structure of the carbon template. The mesopore surface area of the alumina can be as high as 365 m2 g−1, and the pore volume reaches 1.55 cm3 g−1 after calcination at 600 °C in air for 8 h. The pore parameters can be varied within a certain range by variation of the carbon aerogel template and the loading amount of the alumina precursor. At high loadings, the obtained glassy alumina clearly has a bimodal pore size distribution in the mesopore range.
Structure Determination of Homoleptic AuI, AgI, and CuI Aryl/Alkylethynyl Coordination Polymers by X‐ray Powder Diffraction
Authors: Chui Stephen S. Y. , Ng Miro F. Y. , Che Chi‐Ming
Published: January 2005

This article describes the structure determination of five homoleptic d10 metal–aryl/alkylacetylides [RCCM] (M=Cu, R=tBu 1, nPr 2, Ph 3; R=Ph, M=Ag 4; Au 5) by using X‐ray single‐crystal and powder diffraction. Complex 1⋅C6H6 reveals an unusual Cu20 catenane cluster structure that has various types of tBuCC→Cu coordination modes. By using this single‐crystal structure as a starting model for subsequent Rietveld refinement of X‐ray powder diffraction data, the structure of the powder synthesized from CuI and tBuCCH was found to have the same structure as 1. Complex 2 has an extended sheet structure consisting of discrete zig‐zag Cu4 subunits connected through bridging nPrCC groups. Complex 3 forms an infinite chain structure with extended CuCu ladders (CuCu=2.49(4)–2.83(2) Å). The silver(I) congener 4 is iso‐structural to 3 (average AgAg distance 3.11 Å), whereas the gold(I) analogue 5 forms a Au⋅⋅⋅Au honeycomb network with PhCC pillars (AuAu=2.98(1)–3.26(1) Å). Solid‐state properties including photoluminescence, ν(CC) stretching frequencies and thermal stability of these polymeric systems are discussed in the context of the determined structures.
Room‐Temperature Phosphorescence and Energy Transfer in Luminescent Multinuclear Platinum(II) Complexes of Branched Alkynyls
Authors: Tao Chi‐Hang , Zhu Nianyong , Yam Vivian Wing‐Wah
Published: January 2005

A series of luminescent branched platinum(II) alkynyl complexes, [1,3,5‐{RCC(PEt3)2PtCCC6H4CC}3C6H3] (R=C6H5, C6H4OMe, C6H4Me, C6H4CF3, C5H4N, C6H4SAc, 1‐napthyl (Np), 1‐pyrenyl (Pyr), 1‐anthryl‐8‐ethynyl (HCCAn)), [1,3‐{PyrCC(PEt3)2PtCCC6H4CC}2‐5‐{(iPr)3SiCC}C6H3], and [1,3‐{PyrCC(PEt3)2PtCCC6H4CC}2‐5‐(HCC)C6H3], was successfully synthesized by using the precursors [1,3,5‐{Cl(PEt3)2PtCCC6H4CC}3C6H3] or [1,3‐{Cl(PEt3)2PtCCC6H4CC}2‐5‐{(iPr)3SiCC}C6H3]. The X‐ray crystal structures of [1,3,5‐{MeOC6H4CC(PEt3)2PtCCC6H4CC}3C6H3] and [1,8‐{Cl(PEt3)2PtCC}2An] have been determined. These complexes were found to show long‐lived emission in both solution and solid‐state phases at room temperature. The emission origin of the branched complexes [1,3,5‐ {RCC(PEt3)2PtCCC6H4CC}3C6H3] with R=C6H5, C6H4OMe, C6H4Me, C6H4CF3, C5H4N, and C6H4SAc was tentatively assigned to be derived from triplet states of predominantly intraligand (IL) character with some mixing of metal‐to‐ligand charge‐transfer (MLCT) (dπ(Pt)→π*(CCR)) character, while the emission origin of the branched complexes with polyaromatic alkynyl ligands, [1,3,5‐{RCC(PEt3)2PtCCC6H4CC}3C6H3] with R=Np, Pyr, or HCCAn, [1,3‐{PyrCC(PEt3)2PtCCC6H4CC}2‐5‐{(iPr)3SiCC}C6H3], [1,3‐{PyrCC(PEt3)2PtCCC6H4CC}2‐5‐(HCC)C6H3], and [1,8‐{Cl(PEt3)2PtCC}2An], was tentatively assigned to be derived from the predominantly 3IL states of the respective polyaromatic alkynyl ligands, mixed with some 3MLCT (dπ(Pt)→π*(CCR)) character. By incorporating different alkynyl ligands into the periphery of these branched complexes, one could readily tune the nature of the lowest energy emissive state and the direction of the excitation energy transfer.
Preferred Conformations of Peptides Containing tert‐Leucine, a Sterically Demanding, Lipophilic α‐Amino Acid with a Quaternary Side‐Chain Cβ Atom
Authors: Formaggio Fernando , Baldini Chiara , Moretto Vittorio , Crisma Marco , Kaptein Bernard , Broxterman Quirinus B. , Toniolo Claudio
Published: January 2005

Terminally protected homopeptides of tert‐leucine, from the dimer to the hexamer, co‐oligopeptides of tert‐leucine in combination with α‐aminoisobutyric acid or glycine residues up to the hexamer level, and simple dipeptides representing known scaffolds for catalysts in asymmetric organic reactions were prepared by solution methods and fully characterized. The results of conformation analysis, performed by use of FT‐IR absorption, NMR, CD, and X‐ray diffraction techniques, indicate that this hydrophobic α‐amino acid with tetrasubstitution at the Cβ atom is structurally versatile. We show that it prefers extended or semiextended conformations, but can also be accommodated in folded structures, provided that these are biased by the presence of helicogenic residues. The current large‐scale production of Tle, combined with its conformational preferences unravelled in this work, should make this bulky, hydrophobic, Cα‐trisubstituted α‐amino acid a regular building block of any strategy seeking to tailor peptides with improved catalytic and pharmacological properties.
Stereoselective Syntheses of Dihydroxerulin and Xerulinic Acid, Anti‐Hypocholesterolemic Dyes from the Fungus Xerula melanotricha
Authors: Sorg Achim , Siegel Konrad , Brückner Reinhard
Published: January 2005

The title compounds 2 and 3, which are inhibitors of the biosynthesis of cholesterol, were synthesized in a convergent and perfectly stereoselective manner. In the key step, bromobutenolide 6 (obtained from levulinic acid in two steps) was coupled with either of the novel bis(stannanes) trans,cis,trans‐35 or trans,trans,trans‐35 [each accessible from 3‐(tributylstannyl)allyl alcohol (17) in four steps], giving γ‐alkylidenebutenolide trans,trans,trans‐32. This compound was coupled with iododiyne 42 or the bromoenediynoate 44 leading to dihydroxerulin (2) and to the (trimethylsilylethyl)ester 45 of xerulinic acid, respectively. Deprotection of the latter provided totally synthetic xerulinic acid (3) for the first time.
Structures and Magnetic Properties of Tetranuclear Nickel(II) Complexes with Unusual μ3‐1,1,3 Azido Bridges
Authors: Meyer Franc , Demeshko Serhiy , Leibeling Guido , Kersting Berthold , Kaifer Elisabeth , Pritzkow Hans
Published: January 2005

Pyrazolate‐based dinucleating ligands with thioether‐containing chelate arms have been used for the synthesis of a family of novel tetranuclear nickel(II) complexes [L2Ni4(N3)3(O2CR)](ClO4)2 that incorporate three azido bridges and one carboxylate (R = Me, Ph). Molecular structures have been elucidated by X‐ray crystallography in four cases, revealing Ni4 cores with a unique topology in which two of the azido ligands adopt an unusual μ3‐1,1,3 bridging mode. The compounds were further characterized by mass spectrometry, IR spectroscopy, and variable‐temperature magnetic susceptibility measurements. Magnetic data analyses indicate a combination of significant intramolecular ferromagnetic and antiferromagnetic exchange interactions that give rise to an overall ST = 0 ground state. The sign and the magnitude of the individual couplings have been rationalized in the framework of the common magnetostructural correlations for end‐to‐end and end‐on azido linkages, suggesting that these correlations also remain valid for the respective fragments of multiply bridging μ3‐1,1,3 azido ligands.
The Clusters [Ma(ECp*)b] (M=Pd, Pt; E=Al, Ga, In): Structures, Fluxionality, and Ligand Exchange Reactions
Authors: Steinke Tobias , Gemel Christian , Winter Manuela , Fischer Roland A.
Published: January 2005

The synthesis and structural characterization of the novel homoleptic cluster complexes [Pd2(GaCp*)2(μ2‐GaCp*)3] (1 c), [Pd3(GaCp*)4(μ2‐GaCp*)4] (2 b) and [Pd3(AlCp*)2(μ2‐AlCp*)2(μ3‐AlCp*)2] (3) (Cp*=C5Me5) are presented. Furthermore, ligand exchange reactions of these cluster complexes are explored. In contrast to the electronically and sterically saturated complexes [M(ECp*)4] (M=Ni, Pd, Pt), the new unsaturated analogues [Ma(ER)b] (E=Al, Ga, In) react with a variety of typical ligands (Cp*Al, CO, phosphines, isonitriles) to give new di‐ and tri‐substituted compounds like [Pt2(GaCp*)2(μ2‐AlCp*)3] (1 d), [PdPt(GaCp*)(PPh3)(μ2‐GaCp*)3] (4 b), or [Pd3(PPh3)3(μ2‐InCp*)(μ3‐InCp*)2] (8). The trends of the reactivity of [Ma(ER)b] as well as their fluxional behavior in solution has been elucidated by NMR spectroscopy, resulting in a mechanistic rationale for the ligand exchange reactions as well as the fluxional processes.
Metal Phosphonates Applied to Biotechnologies: A Novel Approach to Oligonucleotide Microarrays
Authors: Bujoli Bruno , Lane Sarah M. , Nonglaton Guillaume , Pipelier Muriel , Léger Jean , Talham Daniel R. , Tellier Charles
Published: January 2005

A new process for preparing oligonucleotide arrays is described that uses surface grafting chemistry which is fundamentally different from the electrostatic adsorption and organic covalent binding methods normally employed. Solid supports are modified with a mixed organic/inorganic zirconium phosphonate monolayer film providing a stable, well‐defined interface. Oligonucleotide probes terminated with phosphate are spotted directly on to the zirconated surface forming a covalent linkage. Specific binding of terminal phosphate groups with minimal binding of the internal phosphate diesters has been demonstrated. The mixed organic/inorganic thin films have also been extended for use arraying DNA duplex probes, and therefore represent a viable general approach to DNA‐based bioarrays. Ideas for interfacing mixed organic/inorganic interfaces to other bioapplications are also discussed.
Direct asymmetric aldol reactions catalyzed by (4R)‐4‐(β‐Naphthalenyl)methoxy‐(S)‐proline
Authors: Shen Zongxuan , Chen Wuhong , Jiang Hong , Ding Yi , Luo Xiaoqing , Zhang Yawen
Published: January 2005

A novel proline derivative, (4R)‐4‐(β‐Naphthalenyl)methoxy‐(S)‐proline, was conveniently prepared from the naturally occurring (4S)‐hydroxy‐(S)‐proline; 5 mol % of this compound efficiently catalyzes the asymmetric aldol reactions of various benzaldehydes with acetone in excess of acetone as the solvent, giving the aldol adducts in good yields with ee up to 89.8%. Chirality 17:119–120, 2005. © 2005 Wiley‐Liss, Inc.
The association of body mass index and prostate‐specific antigen in a population‐based study
Authors: Baillargeon Jacques , Pollock Brad H. , Kristal Alan R. , Bradshaw Patrick , Hernandez Javier , Basler Joseph , Higgins Betsy , Lynch Steve , Rozanski Thomas , Troyer Dean , Thompson Ian
Published: January 2005

BACKGROUND

Recent studies of men with prostate carcinoma suggest that obesity may be associated with more advanced‐stage disease and lower overall survival rates. One possible link between body mass index (BMI) and prostate carcinoma prognosis may be disease ascertainment. Prostate‐specific antigen (PSA) is widely used to screen for prostate carcinoma.

METHODS

The authors examined the association between BMI and PSA in a population‐based study of 2779 men without prostate carcinoma. Between 2001 and 2004, these men were enrolled in a study sponsored by the San Antonio Center of Biomarkers of Risk, a clinical and epidemiologic center of the Early Detection Research Network of the National Cancer Institute.

RESULTS

The mean PSA value decreased in a linear fashion with an increase in BMI category, from 1.01 ng/mL in normal weight men to 0.69 ng/mL in obese (Class III) men, after adjusting for race/ethnicity and age.

CONCLUSIONS

Lower levels of PSA in obese and overweight men could mask biologically consequential prostate carcinoma. Cancer 2005. Published 2005 by the American Cancer Society.
Prospective evaluation of major vascular events in patients with nonsmall cell lung carcinoma treated with cisplatin and gemcitabine
Authors: Numico Gianmauro , Garrone Ornella , Dongiovanni Vincenzo , Silvestris Nicola , Colantonio Ida , Di Costanzo Gianna , Granetto Cristina , Occelli Marcella , Fea Elena , Heouaine Abdelamid , Gasco Milena , Merlano Marco
Published: January 2005

BACKGROUND

Cancer and cisplatin‐based chemotherapy both are well recognized risk factors for coagulation disorders and thrombosis. However, vascular events (VEs) seldom are considered adverse effects of treatment and may not even be taken into account in reports of chemotherapy trials.

METHODS

VEs were recorded prospectively in a population of patients with nonsmall‐cell lung carcinoma (NSCLC) who were treated consecutively with cisplatin and gemcitabine using a diagnostic flow chart based on a thorough clinical examination, hematologic and coagulative parameters, and imaging assessments when appropriate.

RESULTS

From January, 2000 to January 2003, 108 patients with Stage III–IV NSCLC underwent chemotherapy and were evaluated. Overall, 22 VEs occurred in 19 patients (17.6%; 95% confidence interval [95% CI], 10.3–24.8%), including 10 arterial VEs (2 myocardial infarctions, 7 lower limb arterial thrombosis, and 1 ischemic stroke) and 12 venous VEs (3 catheter‐related upper limb VEs, 6 venous thrombosis of the lower limb, and 3 pulmonary embolisms). The cumulative proportion of VEs at 1 year after the start of chemotherapy was 22.0% (95% CI, 12.7–31.3%). Four patients died due to the VE (overall mortality, 3.7%), and 3 patients needed surgical revascularization. In the other patients, conservative medical treatment was effective. Baseline patient‐related and disease‐related characteristics of the patients with VEs did not differ significantly from the characteristics of patients without VE; liver and brain metastases were more frequent in patients with VE, although the difference did not reach statistical significance. Response rates were similar in the two groups. A double VE was detected in three patients who were given further chemotherapy after resolution of the first event.

CONCLUSIONS

VEs were a common finding in chemotherapy‐treated NSCLC patients. Chemotherapy itself seem to be a powerful risk factor for VE. Strategies to predict the occurrence of VEs should be developed to spare this life‐threatening toxicity. Cancer 2005. © 2005 American Cancer Society.
Differential expression of Eph receptors and ephrins in the cochlear ganglion and eighth cranial nerve of the chick embryo
Authors: Siddiqui Shazia A. , Cramer Karina S.
Published: January 2005

The cochleovestibular ganglion of the chick differentiates at early embryonic stages as VIIIth nerve axons enter the brainstem. The tonotopic organization of the auditory portion of the VIIIth nerve can be discerned at the time axons initially reach their brainstem targets. The mechanisms underlying this early organization are not known. Eph receptor tyrosine kinases and their ligands, the ephrins, have a demonstrated role in guiding axons to topographically appropriate locations in other areas of the nervous system. In order to begin to test whether Eph proteins have a similar role in the auditory system, we investigated the tonotopic expression of several Eph receptors and ephrins in the VIIIth nerve during embryonic ages corresponding to the initial innervation of the auditory brainstem. Expression patterns of EphA4, EphB2, EphB5, ephrin‐A2, and ephrin‐B1 were evaluated immunohistochemically at embryonic days 4 through 10. Protein expression was observed in the cochlear ganglion and VIIIth nerve axons at these ages. EphB5, ephrin‐A2, and ephrin‐B1 were expressed throughout the nerve. EphA4 and EphB2 had complementary expression patterns within the nerve, with EphA4 expression higher in the dorsolateral part of the nerve and EphB2 expression higher in the ventromedial part of the nerve. These regions may correspond to auditory and vestibular components, respectively. Moreover, EphA4 expression was higher toward the low‐frequency region of both the centrally and peripherally projecting branches of cochlear ganglion cells. Regional variation of Eph protein expression may influence the target selection and topography of developing VIIIth nerve projections. J. Comp. Neurol. 482:309–319, 2005. © 2005 Wiley‐Liss, Inc.
Distribution of L1cam mRNA in the adult mouse brain: In situ hybridization and Northern blot analyses
Authors: Horinouchi Kazuhiro , Nakamura Yukiko , Yamanaka Hiroki , Watabe Takashi , Shiosaka Sadao
Published: January 2005

Previous immunohistochemical analysis revealed a wide distribution of L1cam‐positive neural and nonneural structures in adult mouse brain. Although there were numerous punctate immunoreactive nerve terminals, only a few immunoreactive neuronal cell somata were present (Munakata et al. [2003] BMC Neurosci. 4:7). To explore the distribution of L1cam mRNA‐containing cells, which are interpreted to be L1cam‐producing cells, we performed in situ hybridization histochemistry with an antisense L1cam cRNA probe. L1cam mRNA was distributed widely from the olfactory bulb to the upper cervical cord with an uneven localization pattern in adult brain. All positive cell somata with silver grains after emulsion autoradiography were neuronal, and no grains were detected on nonneural cells in the present study. A high density of signals for neuronal L1cam mRNA was found in the thalamus, mammillary body, and hippocampus. In addition, strong hybridization signals were localized in various nuclei: main and accessory olfactory bulb, compact part of the substantia nigra, pontine gray matter, tegmental reticular nucleus, Edinger‐Westphal nucleus, trigeminal motor nucleus, locus coeruleus, mesencephalic trigeminal nucleus, raphe nuclei, facial nucleus, ambiguus nucleus, dorsal motor vagal nucleus, and inferior olivary nucleus. Some long projection neurons such as the pyramidal, mitral, principal neurons of several cranial nuclei, and presumably monoaminergic cells containing noradrenalin, dopamine, and serotonin, expressed high levels of L1cam. J. Comp. Neurol. 482:386–404, 2005. © 2005 Wiley‐Liss, Inc.
Acoustic stria: Anatomy of physiologically characterized cells and their axonal projection patterns
Authors: Smith Philip H. , Massie Ann , Joris Philip X.
Published: January 2005

The mammalian cochlear nucleus (CN) has been a model structure to study the relationship between physiological and morphological cell classes. Several issues remain, in particular with regard to the projection patterns and physiology of neurons that exit the CN dorsally via the dorsal (DAS), intermediate (IAS), and commissural stria. We studied these neurons physiologically and anatomically using the intra‐axonal labeling method. Multipolar cells with onset chopper (OC) responses innervated the ipsilateral ventral and dorsal CN before exiting the CN via the commissural stria. Upon reaching the midline they turned caudally to innervate the opposite CN. No collaterals were seen innervating any olivary complex nuclei. Octopus cells typically showed onset responses with little or no sustained activity. The main axon used the IAS and followed one of two routes occasionally giving off olivary complex collaterals on their way to the contralateral ventral nucleus of the lateral lemniscus (VNLL). Here they can have elaborate terminal arbors that surround VNLL cells. Fusiform and giant cells have overlapping but not identical physiology. Fusiform but not giant cells typically show pauser or buildup responses. Axons of both cells exit via the DAS and take the same course to reach the contralateral IC without giving off any collaterals en route. J. Comp. Neurol. 482:349–371, 2005. © 2005 Wiley‐Liss, Inc.
Comparative analysis ofCorazonin‐encoding genes (Crz's) inDrosophilaspecies and functional insights intoCrz‐expressing neurons
Authors: Choi Youn J. , Lee Gyunghee , Hall Jeffrey C. , Park Jae H.
Published: January 2005

To gain insight into regulatory mechanisms of tissue‐specificCorazonin(Crz) gene expression and its functions inDrosophila, we cloned theCrzgenes from fourDrosophilaspecies (D. melanogaster, D. simulans, D. erecta, andD. virilis) and performed comparative analyses ofCrzgene sequences and expression patterns using in situ hybridization and immunohistochemistry. AlthoughCrzgene sequences showed a great deal of diversity, its expression patterns in the CNS were highly conserved in theDrosophilaspecies examined here. InD. melanogasterlarva,Crzexpression was found in four pairs of neurons per cerebral lobe and in eight pairs of bilateral neurons in the ventral nerve cord; in adult, the number ofCrz‐producing neurons increased to 6–8 in the pars lateralis of each brain lobe, whereas neurons in the ventral nerve cord were no longer detectable.Crztranscripts were also found in the optic lobes; however, these mRNAs do not seem to be translated. Such adult‐likeCrzexpression patterns were established within 48 hours after pupation. Somata ofCrz‐neurons in the pars lateralis are located in the vicinity of terminals emanating from PDF‐containing pacemaking neurons, indicating a functional connection between the two peptidergic nervous systems. A subset ofCrzneurons coexpressed theperiodclock gene; however, normalCrztranscription was unaffected by central clockworks. Two pairs of ectopicCrzcells were detected in the adult brains of behaviorally arrhythmicClockJrkorcycle02mutants, suggesting that CLOCK and CYCLE proteins negatively regulateCrztranscription in a cell‐specific manner. J. Comp. Neurol. 482:372–385, 2005. © 2005 Wiley‐Liss, Inc.
Erratum: Corrêa SAL, 2004. Re‐evaluation of the afferent connections of the pituitary in the weakly electric fish Apteronotus leptorhyncus: an in vitro tract‐tracing study. J Comp Neurol 470:39‐49.
Authors: Corrêa Sônia A.L. , Zupanc Günther K.H.
Published: January 2005

The original article to which this Erratum refers was published in The Journal of Comparative Neurology (2004) 482: 39–49.
Comparison between the dynamic behaviour of Chua–Yang and full‐range cellular neural networks
Authors: Corinto F. , Gilli M.
Published: January 2005

The mathematical model of a cellular neural network (CNN) consists of a large set of coupled non‐linear differential equations that has been mainly studied through numerical simulations; the knowledge of the dynamic behaviour is essential for developing rigorous design methods and for establishing new applications. This manuscript is devoted to a comparison of the dynamic behaviours of two CNN models: the original Chua–Yang model and the full‐range model that was exploited for VLSI implementations. It is shown that, even if the two models exhibit similar properties, they are not topologically equivalent, i.e. there exist sets of identical parameters for which they present a qualitatively different dynamic behaviour. Copyright © 2003 John Wiley & Sons, Ltd.
On the simultaneous amplitude and phase approximations of wave digital lattice filters
Authors: Yaseen M.
Published: January 2005

The paper presents new solution for the problem of simultaneously approximating the amplitude and phase functions of wave digital lattice filters. The approximation is relying on translating the amplitude and phase specifications into corresponding specifications for the difference and sum phase functions of the two branch polynomials. As a consequence, the phase specifications for each of the two branch polynomials is determined. Accordingly, these two polynomials are generated such that the amplitude and phase functions are approximated alternatively. This means that while one of these functions is approximated, the other is fixed. By iterating this alternative process, the two functions converge to their optimal response. Copyright © 2003 John Wiley & Sons, Ltd.
A novel compact piecewise‐linear representation
Authors: Wen Chengtao , Wang Shuning , Zhang Hao , Khan Muhammad Junaid
Published: January 2005

A new compact MAX representation for 2‐D continuous piecewise‐linear (PWL) functions is developed in this paper. The representation is promising since it can be easily generalized into higher dimensions. We also establish the explicit functional form of basis function and demonstrate that the proposed basis function is the elementary ‘building block’ from which a fully general 2‐D PWL function can be constructed. In addition, we reveal the relationship of basis function with minimal degenerate intersection and Hinging Hyperplane, which shows that the MAX model can unify Chua's canonical expression, Li's representation, lattice PWL function and Bremann's Hinging Finding Algorithm into one common theoretical framework. Copyright © 2005 John Wiley & Sons, Ltd.