bluuebunny/crossref_metadata_2025 huggingface dataset:
Separation of fluorescein isothiocyanate‐labeled amines by microchip electrophoresis in uncoated and polyvinyl alcohol‐coated glass chips using water and dimethyl sulfoxide as solvents of background electrolyte
Authors: Varjo Sami J. O. , Ludwig Martin , Belder Detlev , Riekkola Marja‐Liisa
Published: June 2004

On‐chip capillary electrophoresis with uncoated and polyvinyl alcohol‐coated glass channels in aqueous and nonaqueous dimethyl sulfoxide (DMSO) background electrolyte (BGE) solutions was applied in the separation of five amines derivatized with fluorescein‐5‐isothiocyanate. In aqueous BGE at pH 9.2, baseline separation of the analytes was not achieved on uncoated glass chips, but the separation was clearly improved when the chip channels were coated with polyvinyl alcohol (PVA). Separation was successful in nonaqueous DMSO electrolyte solution containing ammonium acetate and sodium methoxide, on both uncoated and PVA‐coated glass microchips. The differences in the pKa values of analytes were probably amplified in DMSO, and all five analytes were at least partly dissociated and were separated. Because the viscosity of DMSO is higher than that of water, the migration times were longer in DMSO.
Determination of protein‐ligand affinity constants from direct migration time in capillary electrophoresis
Authors: Nilsson Mikael , Harang Valerie , Bergström Maria , Ohlson Sten , Isaksson Roland , Johansson Gunnar
Published: June 2004

A simple method to calculate dissociation constants for protein‐ligand interactions by partial‐filling capillary electrophoresis is demonstrated. The method uses raw migration time data for the ligand and needs only additional information about capillary inner radius and the absolute amount of protein loaded. A theoretical study supported by experimental data also demonstrates that the retention of analyte in affinity capillary electrophoresis (ACE) using the partial‐filling technique depends linearly on the absolute amount of selector added but is independent of both selector zone length and selector mobility. Factors such as field strength and electroosmotic flow are also cancelled out if they are kept constant. The theory is confirmed and the usefulness of the method is demonstrated by enantioseparations using α‐acid glycoprotein (AGP) and cellulase (Cel 7A) as chiral selectors.
Separation of flavonoids and phenolic acids from propolis by capillary zone electrophoresis
Authors: Volpi Nicola
Published: June 2004

The simultaneous determination of twelve different flavonoids, pinocembrin, acacetin, chrysin, rutin, catechin, naringenin, galangin, luteolin, kaempferol, apigenin, myricetin, and quercetin, two phenolic acids, cinnamic acid and caffeic acid, and one stilbene derivative, resveratrol, in propolis extracts used in medicine has been investigated by capillary zone electrophoresis (CZE). With a buffer constituted by sodium tetraborate 30 mM, pH 9.0, and 15 kV applied voltage, the 15 polyphenols were separated on an uncoated fused‐silica capillary within 40 min using normal polarity. Under the experimental conditions used, a linear relationship was calculated between the CZE migration times and the molecular weight of polyphenols' expression of the increasing amount of their hydroxyl groups and polarity. Regression equations revealed a linear relationship (correlation coefficients > 0.97) between the peak area of each polyphenol species and their concentration, from 6 to 120 ng. The levels of analytes in three different propolis extracts, ethanolic, aqueous‐ethanolic and aqueous‐glycolic, used to prepare various commercial medicinal products, were determined. The aqueous‐ethanolic propolis extract showed a great percentage of caffeic acid, galangin, quercetin, and chrysin, whilst the ethanolic preparation was composed of a great amount of resveratrol, chrysin, and caffeic acid. On the contrary, the aqueous‐glycolic propolis preparation was composed of approx. 11% of caffeic acid and a low amount of the other identified flavonoids due to the presence of approx. 85% of nonidentified compounds. CZE represents a valuable method for the qualitative and quantitative assay of the most relevant polyphenol components of propolis, representing an alternative to obtain typical fingerprints of propolis and a reliable identification of a large number of propolis polyphenolic species.
Three‐dimensional flow modelling and sediment transport in the River Klarälven
Authors: Dargahi Bijan
Published: June 2004

A three‐dimensional ﬂow model that uses the RNG k‐ε turbulence model and a non‐equilibrium wall function was applied to the River Klarälven in the southwest part of Sweden. The objectives were to study the nature of the ﬂow in the river bifurcation and to investigate the short‐term sediment transport patterns in the river. The effectiveness of three‐dimensional ﬂow models depends upon: (1) how well the river geometry and it surface roughness are modelled; and (2) the choice of the closure model. Improvements were obtained by modelling the river in two parts: the entire river reach, and a selected part. Composite Manning coefﬁcients were used to account for roughness properties. The method requires a calibration process that ensures the water surface proﬁles match the ﬁeld data. The k‐ε model under‐predicted both the extent of ﬂow separation zones and the number of secondary ﬂow regions having a spiral motion, in comparison with the RNG k‐ε model. The 3‐D model could predict with good accuracy both the general and secondary ﬂow ﬁelds in the river. The results agreed well with the 3‐D velocity measurements using an acoustic Doppler current proﬁler. A conceptual model was developed that accounts for the development of secondary ﬂows in a river bifurcation having two bends. The main ﬂow feature in the river cross‐sections was the existence of multiple counter‐rotating spiral motions. The number of spiral motions increased as the river bends were approached. The river bends also caused vorticity intensiﬁcation and increased the vertical velocities. The application of the 3‐D ﬂow model was extended by solving the sediment continuity equation. The sediment transport patterns were related to the secondary ﬂow ﬁelds in the river. The sediment transport patterns at the river bifurcations are characterized by the growth of a sandbank. Copyright © 2004 John Wiley & Sons, Ltd.
Electrochemical detection of ascorbic acid (vitamin C) using a glassy carbon electrode
Authors: Ly Suw Young , Chae Jung Ik , Jung Young Sam , Jung Woon Won , Lee Hye Jeong , Lee Seong Ho
Published: June 2004

A method for the detection of ascorbic acid (AA) was developed using square wave anodic stripping voltammetric (SWASV) analysis with a glassy carbon electrode (GCE). The results indicated a sensitive oxidation peak current of AA on the GCE. A linear curve was obtained within a concentration range of 1–130.0 μg/L with a preconcentration time of 270 s. The relative standard deviation of 30.0 μg/L observed was 0.1016% (n = 12) under optimum conditions. The low detection limit (S/N) was pegged at 0.30 μg/L. Results showed that the method developed can be used to assay biological and pharmaceutical samples, and food samples, as well as other materials requiring AA analyses.
A study on the lipid fraction of Adriatic sardine filets (Sardina pilchardus)
Authors: De Leonardis Antonella , Macciola Vincenzo
Published: June 2004

Sardine (Sardina pilchardus Walb.) is an important Mediterranean commercial fish species. In this study, the lipids of sardine filets, fished in the Adriatic Sea at different times, were examined. In function of their total lipid (TL) content, sardine filet samples were grouped into lean (TL < 4%) and fat (TL > 4%). It was demonstrated that the differences of TL were exclusively due to a seasonal cyclical increase of neutral lipids. In fact, during moderate‐hot months, sardines accumulated reserve fat that was metabolised during the winter months. The fatty acid composition was similar in both sardine sample groups and the fatty acid profile was equally distributed among saturated fatty acids, on average 38.3%, 31.2% monounsaturated, and 30.4% polyunsaturated. The polyunsaturated fatty acid n3 (PUFA‐n3) represented on average 20.9%, always higher than PUFA‐n6. C20 : 5n3 eicosapentaenoic acid, (EPA) and C22 : 6n3 docosahexaenoic acid (DHA) were the must abundant PUFA‐n3. Under nutritional aspects, the lipids of 100 g of fat‐sardines provided PUFA‐n3 quantities, in particular EPA and DHA, significantly higher than human daily requirements. In lean‐sardines, the PUFA‐n3 input drastically decreased and was estimated that EPA and DHA inputs in 100 g of sardines covered around 17% and 50% of daily requirements, respectively. Finally, cholesterol was equal to 93 mg/100 g of sardines, ranging from 67 to 131 and it did not increase in relation to the total lipid content. In conclusion, this study has highlighted that, under nutritional aspects, regarding EPA and DHA inputs, it is preferable to consume sardines with at least 4% total lipids.
Chemical, technological, and nutritional characteristics of two lines of “farro” (Triticum turgidum ssp. dicoccum)
Authors: Acquistucci Rita , Aureli Gabriella , Codianni Pasquale , Colonna Michaela , Galterio Giovanni
Published: June 2004

In recent years, the renewed interest for foods with a natural image has increased the demand for dry pasta produced from “hulled” wheat such as the Triticum turgidum ssp. dicoccum, also known as “farro”. In order to contribute to the general knowledge, two lines of farro were considered in this study. To have a comparison, an old cultivar of Triticum turgidum ssp. durum (Senatore Cappelli) in addition to a commercial semolina were also examined. All semolina samples were used to produce pasta samples. Results showed some differences among pasta samples that seem to be due not to the presence of specific protein subunits but especially to the quantitative ratio between the different subunits. Results also reconfirmed the role played by the drying technology that is able to affect the sensory characteristics of pasta products.
Purification and physicochemical characterization of ovine β‐lactoglobulin and α‐lactalbumin
Authors: El‐Zahar Khaled , Sitohy Mahmoud , Dalgalarrondo Michèle , Choiset Yvan , Métro François , Haertlé Thomas , Chobert Jean‐Marc
Published: June 2004

Ovine whey proteins were fractionated and studied by using different analytical techniques. Anion‐exchange chromatography and reversed‐phase high‐performance liquid chromatography (HPLC) showed the presence of two fractions of β‐lactoglobulin but only one of α‐lactalbumin. Gel permeation and sodium dodecyl sulfate (SDS)‐polyacrylamide gel electrophoresis allowed the calculation of the apparent molecular mass of each component, while HPLC coupled to electrospray ionisation‐mass spectrometry (ESI‐MS) technique, giving the exact molecular masses, demonstrated the presence of two variants A and B of ovine β‐lactoglobulin. Amino acid compositions of the two variants of β‐lactoglobulin differed only in their His and Tyr contents. Circular dichroism spectroscopy profiles showed pH conformation changes of each component. The thermograms of the different whey protein components showed a higher heat resistance of β‐lactoglobulin A compared to β‐lactoglobulin B at pH 2, and indicated high instability of ovine α‐lactalbumin at this pH.
Spontaneously immortalized human T lymphocytes develop gain of chromosomal region 2p13–24 as an early and common genetic event
Authors: Siwicki Jan Konrad , Berglund Mattias , Rygier Jolanta , Pienkowska‐Grela Barbara , Grygalewicz Beata , Degerman Sofie , Golovleva Irina , Chrzanowska Krystyna H. , Lagercrantz Svetlana , Blennow Elisabeth , Roos Göran , Larsson Catharina
Published: June 2004

To gain further insight into the molecular events responsible for the extended life span and immortalization of human lymphoid cells, we analyzed a series of spontaneously immortalized, IL2‐dependent human T‐cell lines using molecular cytogenetic techniques. Two of the cell lines were derived from normal spleen and three from patients with Nijmegen breakage syndrome (NBS), a recessive disorder characterized by a high incidence of lymphoid malignancies. Here we show that spontaneous immortalization of the five T‐cell lines was associated with the acquisition of copy number gains involving chromosomal region 2p13–24 as common early alterations. In addition, we found an amplification of 8q21–24 after prolonged propagations in all three NBS‐derived cell lines as well as early development of near‐tetraploidy in two of these lines. Gains involving the short arm of chromosome 2 recently were found in several lymphoid malignancies. Therefore, the cell lines described here can be used for identification and characterization of genes involved in the pathogenesis of lymphoid neoplasms and would also provide a useful tool for better understanding the mechanisms responsible for cell immortalization. © 2004 Wiley‐Liss, Inc.
Mapping of a translocation breakpoint in a Peutz–Jeghers hamartoma to the putative PJS locus at 19q13.4 and mutation analysis of candidate genes in polyp and STK11‐negative PJS cases
Authors: Hearle Nicholas , Lucassen Anneke , Wang Rubin , Lim Wendy , Ross Fiona , Wheeler Robert , Moore Isabella , Shipley Janet , Houlston Richard
Published: June 2004

Germ‐line mutations in the serine‐threonine kinase gene STK11 (LKB1) cause Peutz–Jeghers syndrome (PJS), a rare autosomal dominantly inherited disease, characterized by hamartomatous polyposis and mucocutaneous pigmentation. STK11 mutations only account for about half of PJS cases, and a second disease locus has been proposed at chromosome segment 19q13.4 on the basis of genetic linkage analysis in one family. We identified a t(11;19)(q13;q13.4) in a PJS polyp arising from the small bowel in a female infant age 6 days. Because the breakpoint in 19q13.4 may disrupt the putative PJS disease gene mapping to this region, we mapped the breakpoint and analyzed DNA from the case and a series of STK11‐negative PJS cases. Using two‐color interphase fluorescence in situ hybridization, the breakpoint region was refined to a 0.5‐Mb region within 19q13.4. Eight candidate genes mapping to the breakpoint region—U2AF2, EPN1, NALP4, NALP11, NALP5, ZNF444, PTPRH, and KIAA1811—were screened for mutations in germ‐line and polyp DNA from the case and from 15 PJS cases that did not harbor germ‐line STK11 mutations. No pathogenic mutations in the candidate genes were identified. This report provides further evidence of the existence of a second PJS disease locus at 19q13.4 and excludes involvement of eight candidate genes. © 2004 Wiley‐Liss, Inc.
Computational constraints between retrieving the past and predicting the future, and the CA3‐CA1 differentiation
Authors: Treves Alessandro
Published: June 2004

The differentiation between the CA3 and CA1 fields of the mammalian hippocampus is one of the salient traits that set it apart from the organization of the homologue medial wall in reptiles and birds. CA3 is widely thought to function as an autoassociator, but what do we need CA1 for? Based on evidence for a specific role of CA1 in temporal processing, I have explored the hypothesis that the differentiation between CA3 and CA1 may help solve a computational conflict. The conflict is between pattern completion, or integrating current sensory information on the basis of memory, and prediction, or moving from one pattern to the next in a stored sequence. CA3 would take care of the former, while CA1 would concentrate on the latter. I have found the hypothesis to be only weakly supported by neural network simulations. The conflict indeed exists, but two mechanisms that would relate more directly to a functional CA3‐CA1 differentiation were found unable to produce genuine prediction. Instead, a simple mechanism based on firing frequency adaptation in pyramidal cells was found to be sufficient for prediction, with the degree of adaptation as the crucial parameter balancing retrieval with prediction. The differentiation between the architectures of CA3 and CA1 has a minor but significant, and positive, effect on this balance. In particular, for a fixed anticipatory interval in the model, it increases significantly the information content of hippocampal outputs. There may therefore be just a simple quantitative advantage in differentiating the connectivity of the two fields. Moreover, different degrees of adaptation in CA3 and CA1 cells were not found to lead to better performance, further undermining the notion of a functional dissociation. © 2004 Wiley‐Liss, Inc.
Coherent structures in a fully developed stage of a non‐isothermal round jet
Authors: Suto Hitoshi , Matsubara Koji , Kobayashi Mutsuo , Watanabe Hidehito , Matsudaira Yusaku
Published: June 2004

Direct numerical simulation (DNS) was performed for a non‐isothermal air jet with a Reynolds number of 1200 in order to reveal coherent structures of the developed jet. A fourth‐order central finite difference was applied to the simulation. An effort was also made to enable experimental visualization (dye mixing and PTV) to support the validity of the instantaneous structures by DNS. Computational results for two types of inlet profiles suggested that nozzle conditions scarcely affect the turbulence statistics and the coherent structures in a jet‐established stage. Two‐point correlations of velocity and temperature show that similar distributions denoting the temperature can be used as an indicator of a vortex. A conceptual model of a hairpin‐shaped vortex was proposed and validated by two‐point correlations and PDF analysis for vortex alignment. The hairpin‐shaped vortex stands with legs inclined downstream. The inclination angle and the tilting angle between the two legs are −45° and 40°, respectively. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(5): 342–356, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20014
Simulation of coherent structures in turbulent boundary layer using Gao–Yong equations of turbulence
Authors: Liu Bo , Gao Ge , Yong Yan
Published: June 2004

The equations of incompressible turbulent flow developed by the Gao–Yong turbulence model have two important features. First, they do not contain any empirical coefficients or wall functions. Second, the series representation of turbulence energy equation reflects multi‐scale structures of the nonlinearity of turbulence, and, therefore, is capable of describing both statistical mean flows and the coherent structures. This paper presents some simulation results of a two‐dimensional turbulent boundary layer with zero pressure gradient based on Gao–Yong equations of turbulence. With a staggered grid arrangement, an incompressible SIMPLE code was used in the simulations. The simulated coherent structures have verified the adaptability of the newly derived equations to real intermittent turbulent flows. The effect of the orders of the energy equation and computational grid scales on the detection of coherent structures is also investigated. © 2004 Wiley Periodicals, Inc. Heat Trans Asian Res, 33(5): 287–298, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj.20019
Downregulation of the antiapoptotic MCL‐1 protein and apoptosis in MA‐11 breast cancer cells induced by an anti‐epidermal growth factor receptor–Pseudomonas exotoxin a immunotoxin
Authors: Andersson Yvonne , Juell Siri , Fodstad Øystein
Published: June 2004

Pseudomonas exotoxin (PE)–containing immunotoxins (ITs) act by arresting protein synthesis and promoting apoptosis, but the mechanisms of the induced apoptosis and the relationship to protein synthesis inhibition is not well elucidated. We studied these effects in MA‐11 human breast cancer cells treated with 425.3PE, an unmodified PE covalently linked to the 425.3 antibody, which targets the EGF receptor. This IT induced efficient inhibition of protein synthesis with simultaneous induction of apoptosis. Thus, treatment of cells with 10 ng/ml of IT for 5 hr caused 85% inhibition of protein synthesis in parallel with caspase‐3, ‐8 and ‐9 activation and PARP inactivation. Even after 72 hr of IT treatment, preincubation with the broad‐spectrum caspase inhibitor z‐VAD‐FMK caused a significant increase in cell survival without affecting IT‐induced protein synthesis inhibition. Interestingly, a combination of z‐VAD‐FMK and the cathepsin B/L inhibitor z‐FA‐FMK prevented completely IT‐induced cell death in MA‐11 cells after 24 hr, indicating that cathepsin activation may be important for optimal induction of IT‐induced cell death. IT treatment caused after 2.5 hr a significant decrease in the level of the antiapoptotic protein Mcl‐1 but not of Bcl‐2 and Bcl‐XL. Furthermore, Mcl‐1 expression was not sensitive to caspase inhibitors but was totally prevented by the lactacystin proteasome inhibitor, suggesting that IT‐induced apoptosis may be triggered by a reduction in the Mcl‐1 level. Mitochondrial membrane potential (ΔΨ mito) decreased concurrently with caspase activation, showing the involvement of ΔΨ mito as a regulator of IT‐induced apoptosis. Our results demonstrate that 425.3PE‐mediated cell death involves simultaneous induction of apoptosis and protein synthesis inhibition in MA‐11 cells, thus contributing to an understanding of the mechanisms involved in IT‐induced apoptosis. © 2004 Wiley‐Liss, Inc.
Perineal talc exposure and epithelial ovarian cancer risk in the Central Valley of California
Authors: Mills Paul K. , Riordan Deborah G. , Cress Rosemary D. , Young Heather A.
Published: June 2004

Perineal talc use has been suggested as a possible risk factor for ovarian cancer based on its structural similarity to asbestos, a known human carcinogen. A population‐based epidemiologic case‐control study of epithelial ovarian cancer (EOC) was conducted in 22 counties of Central California that comprise the reporting area for 2 regional cancer registries. Telephone interviews were conducted with 256 cases diagnosed in the years 2000–2001 and 1,122 controls frequency‐matched on age and ethnicity. The interview obtained information on demographic factors, menstrual and reproductive experience, exogenous hormone use, surgical history and family history of cancer. Questions on perineal talc use included frequency of use, duration of use and specific years when talc was used. Multivariate‐adjusted odds ratio (OR) and 95% confidence intervals (CI) were derived from unconditional logistic regression. The OR for ever use of talc was 1.37 (CI = 1.02–1.85) compared to never users. However, no dose response association was found. Tubal ligation (TL) modified the effect of talc on EOC such that women with TL had an OR of 0.88 (CI = 0.46–1.68) associated with perineal talc use, whereas women with no TL had an OR of 1.54 (CI = 1.10–2.16). Talc use and EOC risk was highest in women with serous invasive tumors (OR = 1.77; CI = 1.12–2.81). This study provides some support for the hypothesis that perineal talc use is associated with an increased risk of EOC. © 2004 Wiley‐Liss, Inc.
Lipid phosphate phosphatases and related proteins: Signaling functions in development, cell division, and cancer
Authors: Brindley David N.
Published: June 2004

Lipid phosphates initiate key signaling cascades in cell activation. Lysophosphatidate (LPA) and sphingosine 1‐phosphate (S1P) are produced by activated platelets. LPA is also formed from circulating lysophosphatidylcholine by autotaxin, a protein involved tumor progression and metastasis. Extracellular LPA and S1P stimulate families of G‐protein coupled receptors that elicit diverse responses. LPA is involved in wound repair and tumor growth. Exogenous S1P is a potent stimulator of angiogenesis, a process vital in development, tissue repair and the growth of aggressive tumors. Inside the cell, phosphatidate (PA), ceramide 1‐phosphate (C1P), LPA, and S1P act as signaling molecules with distinct functions including the stimulation of cell division, cytoskeletal rearrangement, Ca2+ transients, and membrane movement. These observations imply that phosphatases that degrade lipid phosphates on the cell surface, or inside the cell, regulate cell signaling under physiological and pathological conditions. This occurs through attenuation of signaling by the lipid phosphates and by the production of bioactive products (diacylglycerol, ceramide, and sphingosine). Three lipid phosphate phosphatases (LPPs) and a splice variant dephosphorylate LPA, PA, CIP, and S1P. Two S1P phosphatases (SPPs) act specifically on S1P. In addition, there is family of four LPP‐related proteins (LPRs, or plasticity‐related genes, PRGs). PRG‐1 expression in neurons has been reported to increase extracellular LPA breakdown and attenuate LPA‐induced axonal retraction. It is unclear whether the LRPs dephosphorylate LPA directly, stimulate LPP activity, or bind LPA and S1P. Also, the importance of extra‐ versus intra‐cellular actions of the LPPs and SPPs, and the individual roles of different isoforms is not firmly established. Understanding the functions and regulation of the LPPs, SPPs and related proteins will hopefully contribute to interventions to correct dysfunctions in conditions such as wound repair, inflammation, angiogenesis, tumor growth, and metastasis. © 2004 Wiley‐Liss, Inc.
Ime2p and Cdc28p: Co‐pilots driving meiotic development
Authors: Honigberg Saul M.
Published: June 2004

Meiosis can be considered an elaboration of the cell division cycle in the sense that meiosis combines cell‐cycle processes with programs specific to meiosis. Each phase of the cell division cycle is driven forward by cell‐cycle kinases (Cdk) and coordinated with other phases of the cycle through checkpoint functions (Hartwell and Weinert [1989]: Science. 246:629–634). Meiotic differentiation is also controlled by these two types of regulation (Murakami and Nurse [2000]: Biochem J. 349:1–12; Roeder and Bailis [2000]: Trends Genet. 16:395–403); however, recent study in the budding yeast S. cerevisiae indicates that progression of meiosis is also controlled by a master regulator specific to meiosis, namely the Ime2p kinase (Benjamin et al. [2003]: Genes Dev. 17:1–16; Schindler et al. [2003]: Mol Cell Biol 23:8718–8728). Below, I describe the overlapping roles of Ime2p and Cdk during meiosis in yeast and speculate on how these two kinases cooperate to drive the progression of meiosis. © 2004 Wiley‐Liss, Inc.
Post‐transcriptional control of expression of sFlt‐1, an endogenous inhibitor of vascular endothelial growth factor
Authors: Huckle William R. , Roche Rebecca I.
Published: June 2004

Vascular endothelial growth factor (VEGF) is a major modulator of angiogenesis. Biological effects of VEGF are mediated by endothelial cell‐surface receptors, KDR and Flt‐1. Alternative Flt‐1 RNA processing, involving retention of intron 13 and the use of intronic cleavage‐polyadenylation signals, produces a secreted form of Flt‐1, “sFlt‐1,” that binds VEGF with high affinity and can inhibit VEGF signaling. To probe mechanisms controlling sFlt‐1 expression, we have cloned and sequenced Flt‐1 intron 13 from a mouse genomic library and located RNA processing signals potentially involved in sFlt‐1 mRNA formation. A minigene construct containing Flt‐1 intron 13 directed the expression of both secreted (i.e., cleaved/polyadenylated) and transmembrane (i.e., spliced) forms of Flt‐1 mRNA and protein. Using rapid amplification of 3′ cDNA ends (3′‐RACE) and quantitative PCR (QPCR) analysis to test the activity of intronic cleavage‐polyadenylation signals, we observed that multiple sites were utilized for sFlt‐1 mRNA processing in both native tissues and Flt‐1 minigene transfectants. In transfectants, the most distal signal was utilized preferentially. The potential for interaction between pathways leading to sFlt‐1 or full‐length Flt‐1 was evaluated using QPCR to measure relevant mRNAs after transfection with signal mutants. Decreased expression of sFlt‐1 mRNA in cleavage‐polyadenylation mutants was accompanied by reciprocal increases in full‐length Flt‐1 mRNA. Multiple sFlt‐1 mRNA species are formed that differ by up to 3.9 kb in their 3′‐untranslated regions (UTRs), which contain sites of potential regulatory importance. The reciprocity between sFlt‐1 and Flt‐1 mRNA expression suggests a novel post‐transcriptional mechanism by which sFlt‐1 protein production and, thereby, responsiveness to VEGF, may be modulated. © 2004 Wiley‐Liss, Inc.
Synthesis, separation and biodistribution of 99mTc‐CO‐MIBI complex
Authors: Hao Gui Yang , Zang Jian Ying , Zhu Lin , Guo Yu Zhi , Liu Bo Li
Published: June 2004

99mTc‐CO‐MIBI was prepared by a two‐step procedure involving the convenient preparation of the [99mTc(CO)3(OH2)3]+ precursor and followed by the substitution of the water molecules by the MIBI (2‐methoxyisobutylisonitrile) ligands. In a second step, the reaction solution was adjusted to different pH values, and then the product, 99mTc‐CO‐MIBI, was confirmed to be a mixture of two complexes: complex A and complex B, whose labeling yields could be over 90%. The ratio of complex B to the sum of A and B could increase gradually from 0 to 1 when pH was shifted from 3.0 to 9.0. These changes were monitored by thin layer chromatography (TLC) and high performance liquid chromatography (HPLC). The two complexes were stable within 8 h at room temperature in vitro. The partition coefficient of the two complexes indicated that there was distinct difference between them. Biodistribution in mice demonstrated that complex B showed better myocardial imaging properties than that of complex A. The heart/liver ratios of complex A, the mixture, and complex B were 1.57, 1.93, and 2.33, respectively, for 30 min post‐injection. The discovery of chemical and biological properties of 99mTc‐CO‐MIBI would certainly promote the research on a new promising myocardial perfusion‐imaging agent. Copyright © 2004 John Wiley & Sons, Ltd.
Profiling of sulfoconjugates in urine by using precursor ion and neutral loss scans in tandem mass spectrometry. Application to the investigation of heavy metal toxicity in rats
Authors: Lafaye Alexandra , Junot Christophe , Ramounet‐Le Gall Béatrice , Fritsch Paul , Ezan Eric , Tabet Jean‐Claude
Published: June 2004

This paper reports a liquid chromatographic/electrospray ionization mass spectrometric (LC/ESI‐MS) method for profiling a wide range of structurally different sulfoconjugated compounds in urine and its application to the characterization of biomarkers for heavy metal toxicity in rat urine. Sulfoconjugates were first isolated by solid‐phase extraction and the LC separation was performed on a reversed‐phase column. Sulfoconjugates were detected in a triple‐quadrupole mass spectrometer by simultaneously monitoring constant losses of 80 u (or 80 Th for doubly charged ions), precursors of m/z 80 (SO3−•) and precursors of m/z 97 $(\hbox{HSO}_{4}^{-})$. The ESI‐MS detection conditions were optimized on dehydroepiandrosterone sulfate and estradiol sulfate and tested on other sulfoconjugates. The analysis of urine samples from humans and rats by using the developed method allowed the detection of about 15 peaks in each mode of detection. It was then applied to the investigation of heavy metal toxicity in rats. Comparative analysis of the chromatographic fingerprints of urine from control and uranium‐ and cadmium‐treated rats showed several variations in the chromatographic pattern of the sulfoconjugates. Diagnostic m/z ratios were confirmed by analyzing individual urine samples and one of the observed variations seemed to be specific to uranium toxicity. The ion responsible for this variation has been identified as 4‐ethylphenol sulfate by comparison of its chromatographic retention time and collision‐induced dissociation mass spectra (MS2 and MS3 performed on a quadrupole ion trap instrument) with those of the synthesized compound. Copyright © 2004 John Wiley & Sons, Ltd.
Gas‐phase ion chemistry of the allene–phosphine and silane–allene–phosphine systems
Authors: Operti Lorenza , Rabezzana Roberto , Turco Francesca , Vaglio Gian Angelo
Published: June 2004

The gas‐phase ion chemistry of allene–phosphine and silane–allene–phosphine mixtures was studied by ion trap mass spectrometry. Rate constants of the main processes were measured and compared with the collisional rate constants to determine the reaction efficiencies. For the binary mixture, the highest yield of C‐ and P‐containing ions is obtained with a 1 : 1 partial pressure ratio among the reagents. In the ternary mixture, formation of ion species containing Si, C and P together is mainly achieved in reactions of Si/P ions with allene, with a lower contribution from reactions of Si/C and C/P ions with phosphine and silane, respectively. The formation of ternary ion clusters is related to their possible role as precursors of amorphous silicon carbides doped with phosphorus, obtained by deposition from properly activated silane–allene–phosphine mixtures. Copyright © 2004 John Wiley & Sons, Ltd.
Gas‐phase ion chemistry in the ternary silane–propyne–phosphine system
Authors: Operti Lorenza , Rabezzana Roberto , Turco Francesca , Vaglio Gian Angelo
Published: June 2004

The gas‐phase ion chemistry of propyne–phosphine and silane–propyne–phosphine mixtures was studied by ion trap mass spectrometry. For the binary mixture, the effect of different partial pressures of the reagents on the yield of C and P‐containing ions was evaluated. Reaction sequences and rate constants were determined and reaction efficiencies were calculated from comparison of experimental and collisional rate constants. In the ternary silane–propyne–phosphine systems, the reaction pathways leading to formation of SimCnPpHq+ ions were determined and the rate constants of the most important steps were measured. For some ion species, selected by double isolation procedures (MS/MS), the low ion abundances prevented determination of the reaction rate constants. Si, C and P‐containing ions are mainly produced in reactions of SimPpHq+ ions with propyne, while the reactivity of the SimCnHq+ ions towards PH3 and of the CnPpHq+ ions towards SiH4 is very low. The formation of hydrogenated SiCP ions is interesting for their possible role as precursors of amorphous silicon carbides doped with phosphorus, obtained in a single step, by deposition from properly activated silane–propyne–phosphine mixtures. Copyright © 2004 John Wiley & Sons, Ltd.
Oligosaccharide sequences in Quillaja saponins by electrospray ionization ion trap multiple‐stage mass spectrometry
Authors: Broberg Susanna , Nord Lars I. , Kenne Lennart
Published: June 2004

Ten different samples with 13 previously identified saponin structures from Quillaja saponaria Molina were investigated by electrospray ionization ion trap multiple‐stage mass spectrometry (ESI‐ITMSn) in positive and negative ion modes. Both positive and negative ion mode MS1–MS4 spectra were analyzed, showing that structural information on the two oligosaccharide parts in the saponin can be obtained from positive ion mode spectra whereas negative ion mode spectra mainly gave information on one of the oligosaccharide parts. Analysis of MS1–MS4 spectra identified useful key fragment ions important for the structural elucidation of Quillaja saponins. A flowchart involving a stepwise procedure based on key fragments from MS1–MS3 spectra was constructed for the identification of structural elements in the saponin. Peak intensity ratios in MS3 spectra were found to be correlated with structural features of the investigated saponins and are therefore of value for the identification of terminal monosaccharide residues. Copyright © 2004 John Wiley & Sons, Ltd.
Impact of γ‐irradiation and thermal processing on the antigenicity of almond, cashew nut and walnut proteins
Authors: Su Mengna , Venkatachalam Mahesh , Teuber Suzanne S , Roux Kenneth H , Sathe Shridhar K
Published: June 2004

Whole unprocessed almonds, cashew nuts and walnuts were each subjected to γ‐irradiation (1, 5, 10 and 25 kGy) followed by heat processing including autoclaving (121 °C, 15 psi for 15 and 30 min), dry roasting (138 and 160 °C for 30 min each, 168 and 177 °C for 12 min each), blanching (100 °C for 5 and 10 min), oil roasting (191 °C, 1 min) and microwave heating (500 W for 1 and 3 min). Rabbit polyclonal antibodies were raised against each major protein isolated from defatted, but not subjected to γ‐irradiation and/or any thermal processing, almond, cashew nut and walnut flours. Immunoreactivity of almond, cashew nut and walnut proteins soluble in borate saline buffer, normalised to 1 mg protein ml−1for all samples, was determined by inhibition enzyme‐linked immunosorbent assay (ELISA) and Western blotting. ELISAs and Western blotting experiments indicated that almond, cashew nut and walnut proteins exposed to γ‐irradiation alone or followed by various thermal treatments remained antigenically stable. Copyright © 2004 Society of Chemical Industry
Hydrophilic Polymer Drug from a Derivative of Salicylic Acid: Synthesis, Controlled Release Studies and Biological Behavior
Authors: Rodríguez Gema , Gallardo Alberto , Fernández Mar , Rebuelta Mercedes , Buján Julia , Bellón Juan M , Honduvilla Natalio G , Escudero Cristina , San Román Julio
Published: June 2004

Summary: Hydrophilic polymeric drugs bearing “Triflusal” (4‐trifluoromethylsalicylic acid), a drug widely used as antithrombogenic agent (Disgren®), have been prepared by free radical copolymerization of methacryloyloxyethyl [2‐(acetyloxy)‐4‐(trifluoromethyl)] benzoate (HTRF) and N,N′‐dimethylacrylamide (DMA). The reactivity ratios of both monomers have been determined by 1H NMR spectra by applying non‐linear least square treatments to the copolymerization equation (terminal model), and the kinetic parameters obtained indicated that the microstructure of copolymer chains is homogeneous, with a random distribution of the active HTRF units along the copolymer chains. That means that for the copolymer system THDMA22 used in this work, HTRF units are mainly isolated in relatively long DMA sequences. Therefore, in this structure the intramolecular interactions between adjacent HTRF units are negligible. Release of Triflusal from THDMA22 has been studied in vitro using buffered solutions at pH = 2, 7.4 and 10 and 37 °C. The system showed an interesting pseudo‐zero order release profile at pH = 7.4 during several months. It has been also evaluated the pharmacological activity and the behavior of the system in contact with biological media. In this sense, we have carried out some in vitro studies about the antiaggregant properties and biocompatibility of THDMA22. Results demonstrate that this copolymer inhibits platelet aggregation in its macromolecular form and presents a good biocompatibility with Human Osteoblastic Cells (HOS).

The Figure shows the drug release from THDMA22 at pH = 2 (⋄), 7.4 (□) and 10 (▵).

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The Figure shows the drug release from THDMA22 at pH = 2 (⋄), 7.4 (□) and 10 (▵).
Helical Polymer Carrying Helical Grafts from Peptide‐Based Acetylene Macromonomers: Synthesis
Authors: Sanda Fumio , Gao Guangzheng , Masuda Toshio
Published: June 2004

Summary: N‐Propargylamide‐terminated peptide‐based macromonomers with a degree of polymerization ranging from 4 to 40 were synthesized by the polymerization of γ‐benzyl and γ‐stearyl‐L‐glutamate‐N‐carboxy anhydrides initiated with propargylamine. The macromonomers took an α‐helical structure, which was confirmed by signals at 208 and 220 nm in CD spectra. The macromonomers were subjected to polymerization and copolymerization with an alanine‐derived N‐propargylamide [N‐(tert‐butoxycarbonyl)‐L‐alanine‐N′‐propargylamide] catalyzed with (2,5‐norbornadiene)Rh+[η6‐C6H5B−(C6H5)3]. It was confirmed through a CD spectroscopic study that the copolymer obtained from the copolymerization of the γ‐stearyl‐L‐glutamate‐based macromonomer with the alanine‐derived N‐propargylamide had a helical polyacetylene main chain and helical polypeptide side chains.

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Synthesis of AB Diblock Copolymers by Atom‐Transfer Radical Polymerization (ATRP) and Living Polymerization of α‐Amino Acid‐N‐Carboxyanhydrides
Authors: Brzezinska Krystyna R. , Deming Timothy J.
Published: June 2004

Summary: The synthesis of poly(methyl acrylate)‐block‐poly(γ‐benzyl‐L‐glutamate) (PMA‐b‐PBLG) diblock copolymers, using atom‐transfer radical polymerization (ATRP) of methyl acrylate and living polymerization of γ‐benzyl‐L‐glutamate‐N‐carboxyanhydride (Glu‐NCA) is described. Amido‐amidate nickelacycle end groups were incorporated onto amino‐terminated poly(methyl acrylates), and the resulting complexes were successfully used as macroinitiators for the growth of polypeptide segments. This method allows the controlled preparation of polypeptide‐block‐poly(methyl acrylate) diblock architectures with control over polypeptide chain length and without the formation of homopolypeptide contaminants.

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Applying evolutionary psychology in understanding the representation of women in advertisements
Authors: Saad Gad
Published: June 2004

One of the most ubiquitous creative copy decisions in advertising is to use young attractive women in decorative roles. Contrary to the mantra chanted by some staunch feminists, advertisers are not involved in a patriarchal white‐male‐dominated conspiracy to derogate, exploit, subjugate, and dominate women. Advertisers are concerned with providing messages that are maximally effective to their relevant target audience. Accordingly, they are well aware that in certain situations the use of decorative female models will appeal to a particular group of their constituency. Using evolutionary psychology as the explicative framework, it is argued that the greater use of young and attractive women in decorative roles in advertising is steeped in the differential mating strategies of the two sexes. An analysis of several content‐analytic studies demonstrates that the more frequent use of women as young and attractive decorative models is longitudinally stable and culturally invariant further attesting to the Darwinian roots of this phenomenon. © 2004 Wiley Periodicals, Inc.
Safety of entacapone and apomorphine coadministration in levodopa‐treated Parkinson's disease patients: Pharmacokinetic and pharmacodynamic results of a multicenter, double‐blind, placebo‐controlled, cross‐over study
Authors: Zijlmans Jan C.M. , Debilly Berengere , Rascol Olivier , Lees Andrew J. , Durif Franck
Published: June 2004

We investigated whether administration of the catechol‐O‐methyl transferase (COMT) inhibitor entacapone, at doses of 200 mg and 400 mg, alters the pharmacokinetics of apomorphine in Parkinson's disease patients experiencing severe motor fluctuations. In addition, the pharmacodynamics and safety of entacapone and apomorphine coadministration in these patients were examined. The study followed a three‐sequence, three‐period, crossover design. Patients were randomly assigned to one of three sequences that included single oral doses of entacapone 200 mg, entacapone 400 mg, and placebo in a predefined order. On 3 separate test days, study treatment was administered before apomorphine. The study evaluations (pharmacokinetics, tapping test, and dyskinesia evaluation [Abnormal Involuntary Movements Scale ‐ AIMS]) were performed on these days. Furthermore, Unified Parkinson Disease Rating Scale (UPDRS) scores were evaluated at baseline and study end. Pharmacokinetic parameters for apomorphine (Cmax, AUC, tmax, t1/2) were unchanged by the administration of entacapone, and changes in both the tapping test and AIMS score were similar with all treatments (entacapone 200 mg, entacapone 400 mg, and placebo). There was no significant difference in mean total UPDRS scores between baseline and study end. The administration of entacapone did not change the pharmacokinetic or pharmacodynamic effects of apomorphine in these patients or prolong the clinical effect of apomorphine. Thus, apomorphine may be safely administered to patients receiving therapy with levodopa and entacapone, providing a useful addition to treatment for patients with advanced Parkinson's disease. © 2004 Movement Disorder Society
Impairment of individual finger movements in patients with hand dystonia
Authors: Currà Antonio , Agostino Rocco , Dinapoli Loredana , Bagnato Sergio , Manfredi Mario , Berardelli Alfredo
Published: June 2004

We investigated finger movements in patients with hand dystonia to compare the kinematics of repetitive individual and non‐individual finger oppositions. We used an optoelectronic motion analysis system to record movements in 3‐D space, and recorded three 5‐second trials for each task, counting how many finger oppositions subjects carried out during each trial, and measured the duration and amplitude of flexions, extensions, and pauses. During tasks, normal subjects and patients carried out finger flexions faster than extensions, and invariably they paused longer before extension than before flexion. Patients were slower and paused longer than controls during both individual and non‐individual oppositions. During individual finger movements, patients were disproportionately slow during extension and pause before extension. Patients with hand dystonia perform finger movements abnormally; they are affected predominantly during individual oppositions. This finding reflects the finer cortical control needed to promote and sustain this highly fractionated type of motor output, and points toward underactivity of the primary motor cortex in dystonia. © 2004 Movement Disorder Society
Task‐specific dystonia in tabla players
Authors: Ragothaman Mona , Sarangmath Nagaraja , Jayaram Sachi , Swaminath Pazhayannur V. , Muthane Uday
Published: June 2004

Task‐specific dystonia significantly impairs the performance of approximately 8% of musicians [Lederman RJ. Muscle Nerve 2003;27:549–561]. We describe hand dystonia in two professional musicians experienced while playing tabla, a percussion instrument. © 2004 Movement Disorder Society
Ten‐Hertz stimulation of subthalamic nucleus deteriorates motor symptoms in Parkinson's disease
Authors: Timmermann Lars , Wojtecki Lars , Gross Joachim , Lehrke Ralph , Voges Jürgen , Maarouf Mohammed , Treuer Harald , Sturm Volker , Schnitzler Alfons
Published: June 2004

Recently, a pathological oscillatory network at 10 Hz including several motor areas was described in patients with idiopathic Parkinson's disease (PD). In 7 PD patients, we tested the clinical effect of subthalamic nucleus (STN) stimulation at varying frequencies 1 to 3 years after implantation of electrodes. STN stimulation at 10 Hz induced significant worsening of motor symptoms, especially akinesia, compared with no stimulation and therapeutic stimulation (≥130 Hz). This finding indicates the clinical relevance of pathological 10 Hz synchronization in PD. © 2004 Movement Disorder Society
An integration by parts formula in submanifolds of positive codimension
Authors: Mitrea Marius , Muether Mathew
Published: June 2004

We prove a general integration by parts formula for first‐order differential operators on submanifolds of arbitrary codimension of a given Riemannian manifold. The differential operators in question are assumed to satisfy a suitable tangentiality condition. Several particular cases, particularly relevant to applications to PDE arising in mathematical physics are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Measurement of complex permittivity of thin substrates using the TE01nresonant cavity
Authors: Chen Ming‐Yan , Yu Jian‐Ping , Xu De‐Ming
Published: June 2004

An improved TE01nresonant‐cavity method for measuring the complex permittivity of thin substrates is presented. The theory and the experimental results are described in this paper. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 42: 274–277, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20276