bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth and characterization of bulk AlN substrates grown by PVT
Authors: Bickermann M. , Epelbaum B. M. , Kazan M. , Herro Z. , Masri P. , Winnacker A.
Published: February 2005

We have grown bulk AlN boules by PVT at different growth temperatures. The grown material is single‐phase wurtzite AlN containing about 100 ppm wt of oxygen; transition metals are present only in the sub‐ppm range. Vibrational spectroscopy shows that structural quality of the single‐crystalline areas is high. In FT‐IR reflectivity, an additional maximum showing up in the 900–1000 cm–1 range is attributed to a probably distorted Al2O3 surface layer. In cathodoluminescence performed at 8 K, the samples show a broad luminescence band having its maximum varying between 3.45 eV and 3.85 eV as well as excitonic emission with transition energies of 6.03 eV, 5.93 eV and 5.82 eV. Remarkable variation in peak maximum and width of the broad band even within the same single‐crystalline area is probably caused by local inhomogeneities originating from fluctuations in impurity, e.g. oxygen, or defects concentration. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis and optical properties of Pb‐doped ZnO nanowires
Authors: Zhou Shao‐Min , Zhang Xiao‐Hong , Meng Xiang‐Min , Wu Shi‐Kang , Lee Shuit‐Tong
Published: February 2005

ZnO nanowires and related materials are promising structures for new electronic and optical applications and devices. In the present article featured as Editor's Choice [1], ZnPbO nanowires have been synthesized and studied by structural and photoluminescence investigations.

The cover picture shows in the lower left part a typical transmission electron microscopy (TEM) image of a 7.26% Pb‐doped ZnO nanowire with a diameter of about 70 nm and the corresponding selected area electron diffraction pattern. The upper right figure is a high‐resolution TEM image of an individual nanowire, where the growth direction 〈001〉 is indicated by a white arrow, and a lattice spacing of about 0.26 nm is found.

The corresponding author, Xiaohong Zhang, works on semiconducting materials and nanomaterials synthesis, functionalization of nanomaterials, photochemistry and photophysics, and device characterization. He is Associate Director of the Nano‐Organic Photoelectronic Laboratory in the Technical Institute of Physics and Chemistry of the Chinese Academy of Sciences.
Modeling the free radical polymerization of acrylates
Authors: Günaydin Hakan , Salman Seyhan , Tüzün Nurcan Şenyurt , Avci Duygu , Avi̇yente Vi̇ktorya
Published: February 2005

Acrylates have gained importance because of their ease of conversion to high‐molecular‐weight polymers and their broad industrial use. Methyl methacrylate (MMA) is a well‐known monomer for free radical polymerization, but its α‐methyl substituent restricts the chemical modification of the monomer and therefore the properties of the resulting polymer. The presence of a heteroatom in the methyl group is known to increase the polymerizability of MMA. Methyl α‐hydroxymethylacrylate (MHMA), methyl α‐methoxymethylacrylate (MC1MA), methyl α‐acetoxymethylacrylate (MAcMA) show even better conversions to high‐molecular‐weight polymers than MMA. In contrast, the polymerization rate is known to decrease as the methyl group is replaced by ethyl in ethyl α‐hydroxymethylacrylate (EHMA) and t‐butyl in t‐butyl α‐hydroxymethylacrylate (TBHMA). In this study, quantum mechanical tools (B3LYP/6‐31G*) have been used in order to understand the mechanistic behavior of the free radical polymerization reactions of acrylates. The polymerization rates of MMA, MHMA, MC1MA, MAcMA, EHMA, TBHMA, MC1AN (α‐methoxymethyl acrylonitrile), and MC1AA (α‐methoxymethyl acrylic acid) have been evaluated and rationalized. Simple monomers such as allyl alcohol (AA) and allyl chloride (AC) have also been modeled for comparative purposes. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Effect of magnetic exchange, double exchange, vibronic coupling, and asymmetry on magnetic properties in d2–d3 mixed‐valence dimers
Authors: Yang Xiaohua , Hu Haiquan , Chen Zhida
Published: February 2005

The effect of magnetic exchange, double exchange, vibronic coupling, and asymmetry on magnetic properties of d2–d3 systems is discussed. The temperature‐dependent magnetic moment was calculated with the semiclassical adiabatic approach. The results show that the vibronic coupling from the out‐of‐phase breathing vibration on the metal sites (Piepho, Krausz, and Schatz [PKS] model) and the vibronic coupling from the stretching vibration between the metal sites (P model) favor the localization and delocalization of the “extra” electron in mixed‐valence dimers, respectively. The magnetic properties are determined by the interplay among magnetic exchange, double exchange, and vibronic coupling. The results obtained by analyzing d2–d3 systems can be generalized to other full delocalized dinuclear mixed valence systems with a unique transferable electron. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Theoretical study of two C50H40 isomers with three dodecahedrane cages sharing two pentagons
Authors: Liu Feng‐Ling , Peng Ling , Zhao Jian‐Xia , Wang Shou‐Qing
Published: February 2005

Structures, energies, and vibrational frequencies have been calculated for two C50H40 isomers with three dodecahedrane cages sharing two pentagons at the B3LYP/6‐31G* level of theory. Thus, two C50H40 isomers have the form of coplanar tri‐dodecahedrane‐cage molecules. The symmetry of one isomer is D5d and that of another is C2V. Heats of formation and vertical ionization energies for two C50H40 isomers have been estimated in this study. Heats of formation as well as vibrational analysis indicate that two C50H40 isomers enjoy sufficient stability to allow for its experimental preparation. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Solid sampling technique for direct detection of condensed tannins in bark by matrix‐assisted laser desorption/ionization mass spectrometry
Authors: Ishida Yasuyuki , Kitagawa Kuniyuki , Goto Kuniyoshi , Ohtani Hajime
Published: February 2005

A novel method for the direct analysis of condensed tannin components in bark was developed on the basis of matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) combined with a simple solid sampling technique. The MALDI mass spectra obtained from the wood (bark) powder sample clearly showed a series of peaks corresponding to the sodium ion adducts of condensed tannin oligomers up to around m/z 3000. The results indicate that the condensed tannins in the bark sample used in this work mostly consist of combinations of flavan‐3‐ol units such as profisetinidin (PF), prorobinetinidin (PR) and prodelphinidin (PD), at least up to 10‐mers (m/z ≈3000). Copyright © 2005 John Wiley & Sons, Ltd.
Analysis of the 13C natural abundance of CO2 gas from sparkling drinks by gas chromatography/combustion/isotope ratio mass spectrometry
Authors: Calderone Giovanni , Naulet Norbert , Guillou Claude , Reniero Fabiano , Cortes Ana Isabel Blanch
Published: February 2005

A simple and rapid method to measure naturally occurring δ13C values of headspace CO2 of sparkling drinks has been set up, using direct injections on a gas chromatograph coupled to an isotope ratio mass spectrometer, through a combustion interface (GC/C/IRMS). We tested the method on CO2 gas from several origins. No significant isotopic fractionation was observed nor influences by secondary compounds eventually present in the gas phase. Standard deviation for these measurements was found to be <0.1‰. Copyright © 2005 John Wiley & Sons, Ltd.
Development of a liquid chromatography/tandem mass spectrometry assay for the quantification of PM00104, a novel antineoplastic agent, in mouse, rat, dog, and human plasma
Authors: Yin Jianming , Aviles Pablo , Lee William , Ly Carl , Guillen Maria Jose , Munt Simon , Cuevas Carmen , Faircloth Glynn
Published: February 2005

A rapid and sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) assay was developed and validated to quantify a novel antineoplastic agent, PM00104, in mouse, rat, dog, and human plasma. The method was validated to demonstrate the specificity, limit of quantification (LOQ), accuracy, and precision of measurements. The calibration range for PM00104 was established using PM00104 standards from 0.01–5.0 ng/mL in blank plasma. The selected reaction monitoring (SRM), based on the m/z 692.2 → 218.2 transition, was specific for PM00104, and that based on the m/z 697.2 → 218.2 transition was specific for PM00104 (13C2,2H3) (the internal standard, IS); no endogenous materials interfered with the analysis of PM00104 and IS from blank plasma. The assay was linear over the concentration range 0.01–5.0 ng/mL. The correlation coefficients for the calibration curves ranged from 0.9981–0.9999. The mean intra‐day and inter‐day accuracies for all calibration standards (n = 8) ranged from 97–105% (≤5% bias) in human plasma, and the mean inter‐day precision for all calibration standards was less than 8.5%. The mean intra‐ and inter‐day assay accuracy for all quality control (QC) replicates in human plasma (n = 9), determined at each QC level throughout the validated runs, ranged from 96–112% (≤12% bias) and from 102–105% (≤5% bias), respectively. The mean intra‐ and inter‐day assay precision was less than 15.0 and 11.8% for all QC levels, respectively. For the QC samples prepared in animal species plasma, the %CV values of the assays ranged from 1.8–8.8% in mouse plasma, from 3.7–13.8% in rat plasma, and from 3.0–7.2% in dog plasma. The assay accuracies ranged from 92–102% (≤8% bias) for all QC levels prepared in mouse plasma; ranged from 93–106% (≤7% bias) in rat plasma; and ranged from 95–114% (≤14% bias) in dog plasma. The assay has been used to support preclinical pharmacokinetic and toxicokinetic studies and is currently used to measure PM00104 plasma concentrations to support clinical trials. Copyright © 2005 John Wiley & Sons, Ltd.
Inhibition of protein N-glycosylation has no effect on the binding of acetyl LDL to J774 cells
Authors: Armstrong David P. , White David A.
Published: February 2005

Acetyl-LDL (Ac-LDL) bound to transformed mouse macrophage J774 cells in a high affinity, saturable and specific manner. When cells were cultured for 24h in the presence of tunicamycin such that incorporation of N-linked sugars into protein but not protein synthesis itself was inhibited significantly, the binding characteristics of Ac-LDL to the cells were unaltered. In this respect the Ac-LDL receptor of J774 cells is similar to the asialoglycoprotein receptor of HepG2 cells.
Changes in alanine and glutamine transport during rat red blood cell maturation
Authors: Felipe Antonio , Viñas Octavi , Remesar Xavier
Published: February 2005

Alanine and glutamine transport have been studied during red blood cell maturation in the rat. Kinetic parameters of Na+-dependent L-alanine transport were: Km 0.43 and 1.88 mM and Vmax 158 and 45 nmoles/ml ICW/min for reticulocytes and erythrocytes, respectively. During red cell maturation in the rat there is a loss of capacity and affinity of the system ASC for L-alanine transport. The values for Na+-dependent L-glutamine transport in reticulocytes were Km 0.51 mM and Vmax 157 nmoles/ml ICW/min. On the other hand, a total loss of L-glutamine transport mediated by both N and ASC systems is demonstrated in mature red cells. This seems to indicate that during rat red cell maturation the system N disappears. Furthermore, the system ASC specificity in mature cells changes, and glutamine enters the red cell by non-mediated diffusion processes.
Surface heterogeneity of rat sperm during maturation
Authors: Cartwright Elizabeth J. , Harrington Pauline , Norbury Louise , Leeming Gareth , Sharpe Paul T.
Published: February 2005

Rat sperm isolated from the caput and caudal epididymis and the vas deferens were subjected to multiple partition in aqueous two-phase systems. The technique was used to reveal heterogeneity of a sperm population with respect to particular surface properties. Sperm from all three regions gave broad distributions indicative of heterogeneous cell populations. Greatest heterogeneity was observed for cauda sperm with caput and was sperm producing similar distributions.

Following multiple partition sperm from different regions of the distribution profiles were immunostained with three antibodies known to recognise maturation antigens. The results show that some antigens are acquired during epididymal transit whilst others are present throughout.

The partition (surface heterogeneity) seen cannot therefore be explained solely by the distribution of the antigens recognised by 2D6, 6B2 and 3D5.
Gene conversion in avian mesotocin and vasotocin genes: A recurrent mechanism linking two neurohypophysial precursor lineages?
Authors: Lévy Brigitte , Michel Gilles , Chauvet Jacqueline , Chauvet Marie-Thérèse , Acher Roger
Published: February 2005

Amino acid sequences of the first half of MSEL- and VLDV-neurophysins from goose and chicken have been determined. Identical substitutions in positions 17, 18, 35, 36 and 41 of both neurophysins of a given species when compared with their mammalian counterparts suggest a gene conversion between vasotocin—MSEL-neurophysin and mesotocin—VLDV-neurophysin genes. This event, which has already been observed for three mammalian species, seems recurrent and would link the evolution of the two neurohypophysial hormone precursors.
Methylation of c-myc gene changes in human lymphoproliferative diseases
Authors: Deguchi Yasahiro , Negoro Shigeru , Kishimoto Susumu
Published: February 2005

The degree of methylation at the c-myc proto-oncogene was found to change in human lymphoproliferative diseases, when examined using a methylation-sensitive restriction enzyme. In peripheral blood mononuclear cells (PBMC) c-myc DNA showed hypomethylation in human lymphoproliferative diseases, in comparison to normal subjects matched in age and sex. In cases of chronic lymphocytic leukemia (CLL), the change was amplified in the crisis. When the DNA was examined at the actin gene, no significant change was observed. The results suggest that the change in c-myc proto-oncogene methylation might become an important clue in understanding the relationship between levels of gene expression and methylation in human lymphoproliferative diseases.
Glynn and the conceptual development of the chemiosmotic theory: A retrospective and prospective view
Authors: Weber Bruce H.
Published: February 2005

The origin and evolution of the chemiosmotic theory is described particularly in relation to Peter Mitchell's application of it to model oxidative phosphorylation. Much of the deployment, development and evaluation of the theory occurred at the independent laboratory of the Glynn Research Foundation; the value and future of such an institution is discussed. The role of models mediating between theories and phenomena is analyzed with regard to the growth of knowledge of chemiosmotic systems.
ADP-ribosyl transferase, rearrangement of DNA, and cell differentiation
Authors: Williams Gwyn T. , Johnstone Alan P.
Published: February 2005

Cell differentiation is the process by which genetic information is selectively expressed to produce cells with various morphologies and functions. The integrated changes necessary for this fundamentally important process have recently been the subject of intense study. This review will summarize data from several laboratories correlating differentiation with the activity of the enzyme ADP-ribosyl transferase and with changes in single-strand DNA breaks in various diverse eukaryotic systems. We will then discuss the implications of these observations for differentiation in general, including the possibility that rearrangement of geneticmaterialisa widespread mechanism for controlling gene expression.
Distinction between cofactor-dependent and-independent phosphoglycerate mutases by chromatography on Cibacron Blue-Sepharose
Authors: Price Nicholas C. , Stevens Evelyn
Published: February 2005

The binding of phosphoglycerate mutases from a variety of sources to Cibacron Blue-Sepharose has been examined. Those enzymes which are dependent on 2,3-bisphosphoglycerate (BPG) for activity bind to the immobilized dye and can be eluted by BPG. Those enzymes which are independent of BPG do not bind to the immobilized dye. The possible structural signifi-cance of this distinction is discussed.
Potent and specific blockade by AH 22216 of histamine-H2-receptor-mediated acid secretion in isolated rabbit gastric cells
Authors: Gespach Christian , Menez Isabelle , Emami Shahin
Published: February 2005

AH 22216 is a new histamine-H2-receptor antagonist which possesses a triazole ring. When compared to cimetidine, AH 22216 is about 100 times more potent (Ki = 0.21×10−8 M) in inhibiting histamine-stimulated acid secretion in isolated rabbit gastric cells. These two antihistamines have no effect on carbachol-stimulated acid secretion in the system. The data indicate that AH 22216 interacts directly and specifically on the gastric H2-receptor of the parietal cell and are consistent with the reported pharmacological potencies of AH 22216 and cimetidine on histamine-induced gastric-acid secretion in vivo. AH 22216 could thus be a useful therapeutic agent in patients with peptic ulcers.
A significant pool of amino acids is adsorbed on blood cell membranes
Authors: Picó C. , Pons A. , Palou A.
Published: February 2005

It is well known that the amino acids in the blood are distributed between the plasma and inside the cells. This study was conducted to determine whether amino acids can be located adsorbed on blood cell membranes. The amino acid concentration in the deproteinized haemolysed blood was higher than that in the fraction of blood after removal of the blood cell membranes by centrifugation. These results showed that a pool of amino acids representing 21.1% of the whole blood cell amino acids was adsorbed on the blood cell membranes of adult Wistar rats. The non-polar amino acids showed high adsorption on the membrane, whereas out of the polar amino acid group, only the non-ionic amino acids did adsorb.
Delayed aggregation of proteoglycans in adult human articular cartilage
Authors: Bayliss Michael T. , Ridgway George D. , Ali S. Yousuf
Published: February 2005

The biosynthesis and macromolecular organization of proteoglycans was studied in explants of adult human articular cartilage. In a series of pulse-chase experiments, labelling with (35S)sulphate, it was shown that the proteoglycan monomer is synthesized as a precursor that has a low affinity for hyaluronic acid. These findings suggest a possible mechanism by which the rate of incorporation of proteoglycans into the extraceHular matrix may be controlled.
Sequence analysis of a PM2-DNA anti-Z-IgG-binding region
Authors: Miller F. D. , Winkfein R. J. , Rattner J. B. , Van de Sande J. H.
Published: February 2005

An anti-Z-antibody-binding region between PM2-DNA map units 0.05 and 0.18, containing approx. 25% of the bound PM2 antibody molecules (1,2) has been sequenced. Analysis of this PM2 DNA sequence from map units 0.00 to 0.175 demonstrates that alternating purine/pyrimidine tracts capable of adopting the left-handed conformation are present within this antibody-binding region. Longer (GC)n-rich tracts are clustered together and comprise seven alternating purine/pyrimidine-rich areas (48%–84%) ranging from 19 to 142 nucleotides in length. The DNA located between these alternating purine/pyrimidine-rich areas exhibit a low level (0%–19%) of this sequence arrangement. There is a very strong correlation between the alternating purine/pyrimidine-rich areas and the anti-Z-DNA-IgG-binding sites. Nucleotides 1461–1583 of the PM2-DNA genome encode the bacteriophage capsid protein IV. One of the PM2 left-handed sites is located within this protein-coding sequence; a B-to-Z transition within this site may be involved in protein-IV gene regulation in vivo.
Involvement of ribonucleotide reductase in cellular differentiation
Authors: Creasey David C. , Wright Jim A.
Published: February 2005

L6 and L8 rat myoblast cell lines have been selected for resistance to hydroxyurea, an antineoplastic agent whose intracellular target is the rate-limiting enzyme activity of DNA synthesis, ribonucleotide reductase. In contrast to the differentiation-competent parental lines from which they were selected, the drug-resistant lines exhibit a grossly altered or absent myogenic capacity. Independent selections have revealed a strong correlation between changes in ribonucleotide reductase, as determined by velocity levels and product pool analyses, and altered myogenic potential. These results provide the first indication that alterations in this key enzyme activity and its accompanying deoxyribonucleoside triphosphate pools can affect cellular differentiation.
Isolation of two ATPase inhibitor proteins from mitochondria of rat skeletal muscle
Authors: Yamada Esther W. , Huzel Norman J.
Published: February 2005

An ATPase inhibitor protein was isolated from mitochondria of rat skeletal muscle by alkaline extraction and then was purified, It differed in definitive ways from the ATPase inhibitor protein isolated previously by Ca2+-stripping of submitochondrial particles of rat skeletal muscle. The two ATPase inhibitor proteins were shown to be present together in intact mitochondria.
Structural alterations of the human erythrocyte membrane upon influenza virus attachment
Authors: Herrmann Andreas , Groth Thomas , Lassmann Günter , Ladhoff Axel-M. , Hillebrecht Bärbel
Published: February 2005

Molecular events on the human erythrocyte membrane subsequent to influence virus binding were investigated by electron spin resonance (ESR) measurements after spin labeling of the cell membrane at different positions. Virus binding affected the glycocalyx structure as well as the physical state of the cytoskeleton at the inner leaflet, but not the lipid phase. A lateral reorganization of spin-labeled glycophorin was not indicated after virus attachment.
Efficient degradation in vitro of all intermediate filament subunit proteins by the Ca2+-activated neutral thiol proteinase from Ehrlich ascites tumor cells and porcine kidney
Authors: Vorgias Constantin E. , Traub Peter
Published: February 2005

Vimentin, desmin, glial fibrillary acidic protein, neurofilament triplet proteins, and a mixture of cytokeratins were digested with Ca2+-activated neutral thiol proteinase isolated from Ehrlich ascites tumor (EAT) cells and porcine kidney. All intermediate filament proteins were degraded by the proteinase, although with different rates and Ca2+ optima. These results are in part at variance with our previous statement that the Ca2+-activated proteinase from EAT cells is specific for vimentin and desmin.
Deficiency of erythrocyte C3b receptor (CR1) in AIDS and AIDS-related syndromes
Authors: Tausk Francisco A. , McCutchan J. Allen , Schreiber Robert D. , Spechko Phyllis , Gigli Irma
Published: February 2005

The expression of C3b receptors (CR1) on erythrocytes of gay men at various levels of risk for AIDS was studied. Fourty-nine heterosexual male controls had a mean (X) ± standard deviation of 516 ± 136 CR1 per erythrocyte (CR1-3); 17 asymptomatic gay men had X = 423 ± 156, 16 gay men with one AIDS-related complex (ARC) symptom or sign had X = 342 ± 154, 9 patients with ARC had X = 252 ± 76, and 14 gay men with AIDS had X = 173 ± 76 CR1-E. The patients with ARC and AIDS had a highly significant decrease in CR1-E when compared with normal individuals (p = <0.001) and studies of families of 4 AIDS patients suggest that this defect is acquired.
Cystine-glutamate transport interactions in rat renal cortical tubules, brushborder vesicles, and cultured renal tubule cells
Authors: Foreman John W. , McNamara Pamela D. , Bowring Margaret Ann , Lee Judithann , Rea Claire , Segal Stanton
Published: February 2005

Glutamate had no significant effect on the uptake of 0.025 mM cystine by isolated rat renal cortical tubules and brushborder membrane vesicles in contrast to lysine which significantly inhibits cystine transport. Glutamate, however, markedly inhibited cystine uptake by rat renal tubule cells grown in a serum-free, hormonally defined media for 5 days. Lysine also inhibited cystine transport in these cultured renal tubule cells.
Detection of Atherosis in Preeclamptic Placentas: Comparison of Two Gross Sampling Protocols
Authors: Walford Norman , Htun Kyaw , Akhilesh Meenakshi
Published: February 2005

Two standardized gross sampling protocols were compared with the intention of maximizing the histologic detection rate of atherosis in at-risk (i.e., preeclamptic) placentas. The first, 4-block, protocol was designed to be broadly representative of good current practice (central, edge, en face shave, and membrane roll blocks). A second, 5-block, protocol incorporated all of protocol 1 with the addition of a block composed of multiple flat membrane leaves stacked and sectioned 5 times at 200-μm intervals. Data were available on the first protocol from 80 consecutive accessioned cases of singleton preeclamptic placentas and on the second protocol from 40 cases. Criteria for diagnosis for atherosis were relatively rigorous and excluded “burnt-out” fibrinoid lesions in which foam cells were not positively identified. With the first protocol, atherosis was detected in 30 of 80 (37.5%) of placentas studied. With the second protocol, atherosis was detected in 25 of 40 (62.5%) of placentas studied. This increase was related to a high detection rate of 50% in the flat membrane stack block. Evaluation of the more traditional forms of block produced atherosis detection rates of 2.5% for central full-thickness blocks, 14% for edge blocks, 10% for en face shave blocks, and 25% for membrane rolls. The flat membrane stack was found to be the single most sensitive block for detection of atherosis. When used in conjunction with traditional blocking techniques, it offers significantly increased reliability for detection of atherosis in placentas when maternal vascular compromise is suspected.
Synovial Pathology in Camptodactyly-Arthropathy-Coxa Vara-Pericarditis Syndrome
Authors: Shayan Katayoon , Ho Michael , Edwards Vernon , Laxer Ronald , Thorner Paul S.
Published: February 2005

At least 25 families with camptodactyly-arthropathy-coxa vara-pericarditis (CACP syndrome) have been reported, with descriptions of a distinctive synovial pathology based largely on light microscopy. Although described as “proliferative,” with numerous multinucleated giant cells, the natures of proliferating cells and giant cells have not been determined. To clarify the pathogenesis of this disorder, we studied 3 patients who had CACP syndrome and underwent synovial biopsy. Cells in the biopsies were studied by immunohistochemistry and electron microscopy. Giant cells were identified as macrophage in origin based on CD68 expression and electron microscopic features of macrophages. Most cells in the synovium were CD68 positive, in keeping with macrophages. The degree of proliferation in synovial biopsies was estimated by MIB1 immunostaining, which showed that up to 30% of cells were cycling compared with fewer than 10% in control synovial biopsies. None of the giant cells was cycling. By double immunostaining, proliferating cells were determined to be fibroblastic synoviocytes rather than macrophages. Thus the proliferative synovitis in this CACP syndrome can be more accurately thought of as hypercellularity by infiltrating macrophages with a contribution by proliferating fibroblastic synoviocytes. The synoviocyte proliferation is likely a response to the underlying genetic mutations involving the proteogly-can-4 (or CACP) gene. The encoded protein normally acts as a lubricant and possibly controls cell proliferation. Loss of one or another of these functions may be a possible mechanism that leads to synoviocyte proliferation in this disease, but the exact pathophysiology leading to this change requires further study.
Vitamin D status in patients affected by Smith‐Lemli‐Opitz syndrome
Authors: Rossi M. , Federico G. , Corso G. , Parenti G. , Battagliese A. , Frascogna A. R. , della Casa R. , Dello Russo A. , Strisciuglio P. , Saggese G. , Andria G.
Published: February 2005

Smith‐Lemli‐Opitz syndrome (SLOS) is an inborn error of cholesterol biosynthesis characterized by developmental delay and multiple malformations.Some of the patients have skin photosensitivity and therefore tend to avoid direct exposure to sunlight.SLOS patients typically have low concentrations of cholesterol and abnormally high concentrations of its precursor 7‐dehydrocholesterol (7‐DHC) in biological fluids and tissues. 7‐DHC is also a precursor in the cutaneous synthesis of vitamin D. Sunlight exposure plays a major role in this pathway and reactions transforming 7‐DHC into vitamin D and then into 25‐hydroxyvitamin D are known not to be specifically regulated. The aim of this study was to evaluate vitamin D status in SLOS patients. We measured 25‐hydroxyvitamin D and 1,25‐dihydroxyvitamin D serum concentrations and markers of calcium metabolism in five SLOS patients.Despite abnormally high concentrations of 7‐DHC, circulating concentrations of vitamin D metabolites were not significantly different from appropriate controls matched for sex, age and season of blood collection. The analysis of historical serum samples stored in our laboratory from the same cases plus 10 other SLOS patients further supported these findings. Our data suggest that SLOS patients have a peculiar vitamin D metabolism that protects them from vitamin D intoxication.This appears to be due in most cases to decreased transformation of 7‐DHC into 25‐hydroxyvitamin D, perhaps depending on reduced sunlight exposure as a consequence of photosensitivity. Possible alternative mechanisms are discussed.
Promotion of oxidative stress by 3‐hydroxyglutaric acid in rat striatum
Authors: Latini A. , Scussiato K. , Leipnitz G. , Dutra‐Filho C. S. , Wajner M.
Published: February 2005

The pathophysiology of the striatum degeneration characteristic of patients affected by the inherited neurometabolic disorder glutaryl‐CoA dehydrogenase deficiency (GDD), also known as glutaric aciduria type I, is still in debate. We have previously reported that 3‐hydroxyglutaric acid (3‐OH‐GA) considered the main neurotoxin in this disorder, induces oxidative stress in rat cerebral cotex. In the present work, we extended these studies by investigating the in vitro effect of 3‐OH‐GA, at concentrations ranging from 0.01 to 1.0 mmol/L on the brain antioxidant defences by measuring total radical‐trapping antioxidant potential (TRAP), total antioxidant reactivity (TAR) and glutathione (GSH) levels, and on the production of hydrogen peroxide (H2O2), nitric oxide (NO) and malondialdehyde in striatum homogenates from young rats. We observed that TRAP, TAR and GSH levels were markedly reduced (by up to 50%) when striatum homogenates were treated with 3‐OH‐GA. In contrast, H2O2 (up to 44%), NO (up to 95%) and malondialdehyde levels (up to 28%) were significantly increased by 3‐OH‐GA. These data indicate that total nonenzymatic antioxidant defences (TRAP) and the tissue capacity to handle an increase of reactive species (TAR) were reduced by 3‐OH‐GA in the striatum. Furthermore, the results also reflect an increase of lipid peroxidation, probably secondary to 3‐OH‐GA‐induced free radical production. Thus, it may be presumed that oxidative stress is involved in the neuropathology in GDD.
Glutathione deficiency in patients with mitochondrial disease: Implications for pathogenesis and treatment
Authors: Hargreaves I. P. , Sheena Y. , Land J. M. , Heales S. J. R.
Published: February 2005

Glutathione (GSH) is a key intracellular antioxidant. With regard to mitochondrial function, loss of GSH is associated with impairment of the electron transport chain (ETC). Since GSH biosynthesis is an energy‐dependent process, we postulated that in patients with ETC defects GSH status becomes compromised, leading to further loss of ETC activity. We performed electrochemical HPLC analysis to determine the GSH concentration of 24 skeletal muscle biopsies from patients with defined ETC defects compared to 15 age‐matched disease controls. Comparison of these groups revealed a significant (p <0.001) decrease in GSH concentration in the ETC‐deficient group: 7.7 ± 0.9 vs 12.3 ± 0.6 nmol/mg protein in the control group. Further analysis of the data revealed that patients with multiple defects of the ETC had the most marked GSH deficiency: 4.1 ± 0.9 nmol/mg protein (n = 4, p < 0.05) when compared to the control group. These findings suggest that a deficiency in skeletal muscle GSH concentration is associated with an ETC defect, possibly as a consequence of diminished ATP availability or increased oxidative stress. The decreased ability to combat oxidative stress could therefore cause further loss of ETC activity and hence be a contributing factor in the progressive nature of this group of disorders. Furthermore, restoration of cellular GSH status could prove to be of therapeutic benefit in patients with a GSH deficiency associated with their ETC defects.
On the existence of blowing-up solutions for a mean field equation
Authors: Pistoia Angela , Esposito Pierpaolo , Grossi Massimo
Published: February 2005

In this paper we construct single and multiple blowing-up solutions to the mean field equation:;

\begin{cases} −\mathrm{\Delta }u = \lambda \frac{V(x)\:\mathrm{e}^{u}}{\int _{\Omega }V(x)\:\mathrm{e}^{u}} & \text{in }\Omega \text{,} \\ u = 0 & \text{on }\partial \Omega \text{,}
\end{cases}

where

Ω

is a smooth bounded domain in

\mathbb{R}^{2}

,

V

is a smooth function positive somewhere in

Ω

and

λ

is a positive parameter.

Dans ce papier nous construisons des solutions qui explosent pour l'équation de champ moyen :

\begin{cases}
−\mathrm{\Delta }u = \lambda \frac{V(x)\:\mathrm{e}^{u}}{\int _{\Omega }V(x)e^{u}} & \text{in }\Omega \text{,} \\ u = 0 & \text{on }\partial \Omega \text{,}
\end{cases}

où

Ω

est un domaine borné dans

\mathbb{R}^{2}

,

V

est une fonction positive dans

Ω

et

λ

est un paramètre positif.
Cell death induced by Pteris semipinnata L. is associated with p53 and oxidant stress in gastric cancer cells
Authors: Liu Zhimin , Ng Enders K.W. , Liang Nian-Ci , Deng Yi-feng , Leung Billy C.S. , Chen George G.
Published: February 2005

In this study, we demonstrated that Ent‐11α‐hydroxy‐15‐oxo‐kaur‐16‐en‐19‐oic‐acid (5F) had stronger cytotoxicity against MKN‐45, a gastric cancer cell line bearing wild‐type p53 than MKN‐28, another gastric cancer cell line containing missense mutation in p53. The rapid increase of ROS level was involved in the mechanism of cytotoxicity. Classical features of apoptosis induced by 5F were observed in MKN‐45 cells only or more significant in MKN‐45 cells than MKN‐28 cells. Translocation of Bax from cytosol to mitochondria, reduction of Δψm and DNA fragmentation were induced by 5F in the p53‐dependent manner. We conclude that the expression of Bax and its downstream molecules requires the presentation of a wild‐type p53 in the cells treated by 5F.
When kinases meet mathematics: the systems biology of MAPK signalling
Authors: Kolch Walter , Calder Muffy , Gilbert David
Published: February 2005

The mitogen activated protein kinase/extracellular signal regulated kinase pathway regulates fundamental cellular function such as cell proliferation, survival, differentiation and motility, raising the question how these diverse functions are specified and coordinated. They are encoded through the activation kinetics of the pathway, a multitude of feedback loops, scaffold proteins, subcellular compartmentalisation, and crosstalk with other pathways. These regulatory motifs alone or in combination can generate a multitude of complex behaviour. Systems biology tries to decode this complexity through mathematical modelling and prediction in order to gain a deeper insight into the inner works of signalling networks.
Schwetzingen: Adriana Hölszky's ‘Der gute Gott von Manhattan’
Authors: Dunnett Roderic
Published: February 2005

Adriana Hölszky – Romanian-born, but Stuttgart-based since 1976 – scored a deserved, significant hit when her first opera, Bremer Freiheit, based on Rainer Maria Faessbinder, was staged at the 1988 Munich Biennale. Two other operas – one based on Jean Genet – had their premières in Vienna and Bonn, before Stuttgart's ever-pioneering Württembergisches Landestheater commissioned Giuseppe e Silvia, based on Hans Neuenfels, in 2000. A sheaf of chamber and orchestral works have seen premières at festivals such as Styria and Vienna, and (even more aptly) at Donaueschingen.
Lucerne Festival 2004: Harrison Birtwistle
Authors: Burton Anthony
Published: February 2005

Among major European festivals, the Lucerne Festival is outstanding in the attention it pays to contemporary music. The latest manifestation of this is the founding of an annual Lucerne Festival Academy for young professional players, specializing in the music of the 20th and 21st centuries, under the leadership of Ensemble Intercontemporain and the indefatigable Pierre Boulez. Nor is this is on the modest scale of a ‘young Sinfonietta’: its final concert, conducted by Boulez, began with Harrison Birtwistle's massive Earth Dances.
Presteigne Festival 2004
Authors: Conway Paul
Published: February 2005

The Presteigne Festival in the 21st century is in many ways the natural successor to the post-war years of the Cheltenham Festival, not just in its enlightened choice of first-rate contemporary British music, but in its cultivation of ‘house composers’ who can be spotted browsing in local shops as well as providing the focus of several informal pre-concert talks. In fact, the music of three composers who received their first big commissions from the Cheltenham Festival – William Mathias, Alun Hoddinott and John McCabe – were all celebrated at the 2004 Presteigne Festival.
Proms 2004: Adams, Corigliano, Saariaho
Authors: Stein Robert
Published: February 2005

Like its predecessors Nixon in China and The Death of Klinghoffer, the third opera in John Adams's trilogy, Doctor Atomic, seems set fair to juxtapose modern political forces, personalities and moral debate. Here admiration for Robert Oppenheimer and his fellow geniuses who created the atomic bomb is contrasted with the enormity of destruction wreaked on Hiroshima. With over a year to go to the opera's world première by San Francisco Opera, the composer himself conducted Easter Eve 1945, the opening of Act 2, at the Albert Hall on 22 August with the BBC Symphony Orchestra and Audra McDonald as soloist.
Popov's First Symphony
Authors: MacDonald Calum
Published: February 2005

POPOV: Symphony No. 1, op. 7. SHOSTAKOVICH: Theme and Variations, op.3. London Symphony Orchestra c. Leon Botstein. Telarc CD-80642.
Round Barrows and Dykes as Landscape Metaphors
Authors: Tilley Christopher
Published: February 2005

This article outlines the results of phenomenological research on the significance of landscape features, in particular ridges and coombe (dry valley) systems, in relation to the locations of Bronze Age round barrows and late Bronze Age/early Iron Age crossridge and spur dykes constructed along a chalk ridge in central southern England. It considers the locations of these monuments in a holistic manner and argues that together the round barrows, and then subsequently the dykes, network or draw together very different aspects of the topography in narratives about life and death. The round barrows differentially reference the significance of these places metaphorically through a combination of their specific locations. By contrast, the monumental courses of the dykes physically impose themselves on, or objectify the significance of, the same landscape features, but in a radically different manner indicating both continuity and difference in the historical significance of place.
New Evidence for the Expansion of an Upper Pleistocene Population out of East Africa, from the Site of Station One, Northern Sudan
Authors: Rose Jeffrey I.
Published: February 2005

Evidence for a hunter-gatherer range-expansion is indicated by the site of Station One in the northern Sudan, a surface scatter of chipped stone debris systematically collected almost 40 years ago, though not studied until present. Based on technological and typological correlates in East Africa, the predominant use of quartz pebbles for raw material, and the production of small bifacial tools, the site can be classified as Middle Stone Age. While often appearing in East African assemblages, quartz was rarely used in Nubia, where ferrocrete sandstone and Nile pebble were predominantly used by all other Middle Palaeolithic/Middle Stone Age populations. Additionally, façonnage reduction is characteristic of lithic technology in East Africa in the late Middle Stone Age, while Middle Palaeolithic industries in the Nile Valley display only core reduction. It is proposed this assemblage represents a range-expansion of Middle Stone Age hunter-gatherers from East Africa during an Upper Pleistocene pluvial.
Neolithic Houses and Chambered Tombs of Western France
Authors: Laporte Luc , Tinévez Jean-Yves
Published: February 2005

The Neolithic tombs of northern Europe have often been presented as built in the image of the hous e of the dead. We wish to discuss here the different terms of this proposition in the light of recent discoveries concerning the domestic habitat in western France, whence we draw most of the architectural examples — both funerary and domestic.
Accuracy, standardization, and interlaboratory calibration standards for foraminiferal Mg/Ca thermometry
Authors: Greaves Mervyn , Barker Stephen , Daunt Caroline , Elderfield Henry
Published: February 2005

The use of liquid and solid standards for foraminiferal Mg/Ca and Sr/Ca determinations and interlaboratory calibration has been investigated. Preparation of single element standard solutions from primary solid standard material enables the preparation of mixed standard solutions with Mg/Ca and Sr/Ca ratios of known accuracy to better than 0.1%. We also investigated commercial reference materials to determine whether existing carbonate standards could be used as reference material for Mg/Ca determinations in foraminiferal calcite. We propose that, in the absence of a pure calcium carbonate standard certified for Mg/Ca, ECRM 752‐1, a limestone CRM containing Mg/Ca within the range of typical foraminifera, is a suitable solid standard for interlaboratory calibration. Replicate Mg/Ca determinations showed that, provided silicate phases are removed by centrifugation, this material is homogenous within the precision of daily instrumental Mg/Ca determinations over a range of sample weights from 10 to 1000 mg, taken from two separate bottles of ECRM 752‐1. Results gave an average value of Mg/Ca = 3.75 mmol/mol (0.015 s.d., 0.41% r.s.d.) on 118 determinations from the two bottles.
Stability of the seismic source during effusive and explosive activity at Stromboli Volcano
Authors: Marchetti Emanuele , Ripepe Maurizio
Published: February 2005

In December 2002 Stromboli Volcano erupted triggering a sector collapse and a tsunami. During the 7 month‐long effusive eruption, the typical persistent and moderate explosive activity of Stromboli ceased. However, very long period (VLP) seismic events, typically associated with the explosions at Stromboli, were recorded during the effusive eruption. These were clustered mainly in two groups with stable waveforms. This suggests that strombolian activity never ceased but was confined deep within the magma conduit. A location method, based on the seismic directivity recorded with an asynchronous seismic deployment, positioned the two clusters ∼60 m apart from each other at ∼510 m a.s.l. and ∼180 m NW from the summit craters. However, seismic polarization reveals a ∼50 m upward migration of the VLP source at the end of the eruption when volcanic activity moved from the effusive style to more typical strombolian activity.
Constitutive activity modulation of human metabotropic glutamate 5a receptors in HEK293 cells: a role for key amino‐terminal cysteine residues
Authors: Mühlemann Andreas , Diener Catherine , Fischer Christophe , Piussi Jenny , Stucki Andy , Porter Richard H
Published: February 2005

Several combinations of cysteine to serine mutations at positions 57, 93, 99 and 129 in the extracellular N‐terminal domain of human metabotropic 5a (hmGlu5a) receptors were produced and expressed in HEK293 cells. Quisqualic acid‐induced intracellular calcium ([Ca2+]i) mobilization and inositol phosphates (IP) accumulation revealed an apparent increased efficacy and decreased potency for hmGlu5a mutants C57S, C99S and C57/99S, as well as a total loss of function for the mutant C57/93/99/129S.

[3H]Quisqualate saturation analysis revealed mutants C57S, C99S, C57/99S and the tetramutant C57/93/99/129S to have unchanged KD but reduced Bmax values. [3H]MPEP saturation analysis on the same membrane preparations revealed no difference in KD for any mutant, but a decrease in Bmax value for the C57/93/99/129S receptor.

Inverse agonism of MPEP at hmGlu5a receptors was partially reduced by mutation C57S, significantly reduced by C99S and C57/99S mutations and totally abolished in the tetramutant.

We confirmed the surface expression of all the mutated receptors using [3H]MPEP binding analysis on whole cells. However, Bmax values were increased for mutant C57S, C99S, and C57/99S but decreased in the C57/93/99/129S receptor.

The 24 h preincubation of cells expressing hmGlu5a receptors with 1 μM MPEP followed by extensive washing dramatically increased the wild‐type receptor efficacy to quisqualate, to the same levels seen with C57/99S receptors. MPEP preincubation did not affect C57/99S function.

We conclude that cysteines 57 and 99 are key residues necessary for modulating hmGlu5a receptor function.

British Journal of Pharmacology (2005) 144, 1118–1125. doi:10.1038/sj.bjp.0706152
Chondroitinase ABC I from Proteus vulgaris: cloning, recombinant expression and active site identification
Authors: PRABHAKAR Vikas , CAPILA Ishan , BOSQUES Carlos J. , POJASEK Kevin , SASISEKHARAN Ram
Published: February 2005

GalAGs (galactosaminoglycans) are one subset of the GAG (glycosaminoglycan) family of chemically heterogeneous polysaccharides that are involved in a wide range of biological processes. These complex biomacromolecules are believed to be responsible for the inhibition of nerve regeneration following injury to the central nervous system. The enzymic degradation of GAG chains in damaged nervous tissue by cABC I (chondroitinase ABC I), a broad-specificity lyase that degrades GalAGs, promotes neural recovery. In the present paper, we report the subcloning of cABC I from Proteus vulgaris, and discuss a simple methodology for the recombinant expression and purification of this enzyme. The originally expressed cABC I clone resulted in an enzyme with negligible activity against a variety of GalAG substrates. Sequencing of the cABC I clone revealed four point mutations at issue with the electron-density data of the cABC I crystal structure. Site-directed mutagenesis produced a clone with restored GalAG-degrading function. We have characterized this enzyme biochemically, including an analysis of its substrate specificity. By coupling structural inspections of cABC I and an evaluation of sequence homology against other GAG-degrading lyases, a set of amino acids was chosen for further study. Mutagenesis studies of these residues resulted in the first experimental evidence of cABC I's active site. This work will facilitate the structure–function characterization of biomedically relevant GalAGs and further the development of therapeutics for nerve regeneration.