bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular characterization of a cDNA encoding vitellogenin in the coonstriped shrimp, Pandalus hypsinotus and site of vitellogenin mRNA expression
Authors: Tsutsui Naoaki , Saido‐Sakanaka Hisako , Yang Wei‐Jun , Jayasankar Vidya , Jasmani Safiah , Okuno Atsuro , Ohira Tsuyoshi , Okumura Takuji , Aida Katsumi , Wilder Marcy N.
Published: September 2004

In order to determine the primary structure of vitellogenin in a protandric species, the coonstriped shrimp Pandalus hypsinotus, we previously purified four vitellin components (designated as VnA, VnB, VnC, and VnD, respectively), and chemically analyzed their partial amino acid sequences. In this study, we subsequently cloned a cDNA encoding vitellogenin in this species based on the N‐terminal and internal amino acid sequences of VnA, as well as the N‐terminal sequence of VnC. The open reading frame of this cDNA encoded a pro‐vitellogenin in which vitellins were arranged as follows: NH2–VnA–VnB–VnC/D–COOH. The deduced amino acid sequence possessed a single consensus cleavage sequence, R–X–K/R–R, along the lines of vitellogenins reported in other crustaceans and insects, and the N‐terminal sequence of VnB was immediately preceded by this sequence. The comparison of primary structures revealed the existence of a basic and characteristic structure for the vitellogenin molecule in decapod crustacean species, and phylogenetic analysis reflected the current taxonomic classifications of Crustacea. An approximately 8 kb‐long transcript of the vitellogenin gene was detected in the hepatopancreas of female shrimps having a gonadosomatic index higher than 1.0 by Northern blot analysis, but was not observed in the hepatopancreas and gonads of male shrimps and the hepatopancreas of female shrimps having a gonadosomatic index lower than 1.0. These results indicate that the hepatopancreas is responsible for vitellogenin synthesis. J. Exp. Zool. 301A:802–814, 2004. © 2004 Wiley‐Liss, Inc.
Application of RNA interference to chicken embryos using small interfering RNA
Authors: Sato Fuminori , Nakagawa Tetsuto , Ito Makoto , Kitagawa Yasuo , Hattori Masa‐aki
Published: September 2004

Gene silencing using small interfering RNA (siRNA) is not established in avian species. The present study was performed to evaluate RNA interference (RNAi) in the chicken embryo by using a dual fluorescence reporter assay, a plasmid encoding green fluorescent protein (GFP) and a plasmid encoding red fluorescent protein (RFP). The siRNA targeting the GFP mRNA sequence (GFP‐siRNA) with both plasmids was introduced into cultured cells and whole embryos by lipofection and microelectroporation, respectively. GFP‐ and RFP‐expressed cells and embryos were observed under fluorescent microscopy and analyzed by flow cytometer, and their mRNAs were analyzed by reverse transcription‐PCR (RT‐PCR). The strong fluorescence was observed by introducing both plasmids into cells. The intensity of the green fluorescence generated by GFP was greatly suppressed by introducing GFP‐siRNA. RT‐PCR analysis showed that introducing GFP‐siRNA also decreased GFP mRNA levels. In contrast to GFP, the intensity of the red fluorescence generated by RFP and the RFP mRNA levels remained unchanged. In whole embryos, also, introducing GFP‐siRNA specifically suppressed GFP expression, and the suppression was maintained for at least 72 h. Consequently, it was concluded that the gene silencing using siRNA is applicable to analyzing the function of genes of interest during avian embryogenesis. J. Exp. Zool. 301A:820–827, 2004. © 2004 Wiley‐Liss, Inc.
Histopathologic changes induced by the microtubule‐stabilizing agent Taxol in the rat hippocampus in vivo
Authors: Mercado‐Gómez Octavio , Ferrera Patricia , Arias Clorinda
Published: September 2004

Microtubules and their associated proteins play a prominent role in neuronal morphology, axonal transport, neuronal plasticity, and neuronal degeneration. It has been proposed that microtubule damage is sufficient to induce neuronal death. In this regard, the microtubule‐stabilizing agent Taxol could be a useful tool to reproduce some aspects of neurodegenerative diseases associated with disturbances of the cytoskeleton and alterations in axonal transport. Although differential effects of Taxol on neuronal viability have been found in vitro, Taxol toxicity in the central nervous system remains to be addressed. We studied the effects of Taxol on neuronal morphology and viability as well as changes in microtubule‐associated proteins MAP2 and tau in rat hippocampus. Our results show that Taxol induces dose‐dependent neuronal death accompanied by the loss of MAP2 and the presence of dystrophic neurites. Interestingly paired helical filament (PHF)‐1 immunoreactivity, which is associated with a phosphorylated epitope of tau proteins, was induced in the damaged hippocampus. Our results suggest that microtubule dynamics have a role in maintenance of neuronal morphology and survival in vivo, and that modifications in microtubule dynamics, may alter the content and neuronal distribution of MAP2 and promote alterations in the phosphorylation state of tau. © 2004 Wiley‐Liss, Inc.
Structure determination of ramosine, a guaianolide, by NMR spectroscopy
Authors: Khan Sher Bahadar , Afza Nighat , Malik Abdul , ul Haq Azhar , Ahmed Zaheer
Published: September 2004

Ramosine, a new sesquiterpene lactone, was isolated from the chloroform fraction of Amberboa ramosa and the structure was assigned as 4β‐(hydroxymethyl)‐3β,4α‐dihydroxy‐8α‐[(S)‐3‐hydroxy‐2‐ethylenepropionyloxy]‐1αH, 5αH,6βH,7αH,11βH,11α‐methylguaia‐10(14)‐en‐6, 12‐olide by extensive NMR studies. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis and NMR spectroscopic studies of allylsulfanyl‐N1‐alkyl‐N4‐phenyl‐1,4‐phenylenediamines and their cyclization products, 2,3‐dihydro‐1‐benzothiophenes and thiochromans
Authors: Katritzky Alan R. , Akhmedov Novruz G. , Wang Mingyi , Rostek Charles J. , Steel Peter J.
Published: September 2004

Regioselective addition of allylthiol at the C‐3 position adjacent to the nitrogen carrying the phenyl group of the 1,4‐phenylenediamine moiety of compounds 1–4 was rigorously confirmed by 1D NOE difference in combination with gHMBC experiments. The structures of 1,4‐phenylenediamines 1–4, allylsulfanyl‐N1‐alkyl‐N4‐phenyl‐1,4‐phenylenediamines 5–8 and cyclization products 9–14 were completely analyzed in both CDCl3 and DMSO‐d6 solutions. The 1H and 13C NMR spectra of 10 and 11, which contain two chiral centers, exhibit duplication for several signals, indicating the existence of two diastereomeric forms. The full structures of 5 and 9 were unambiguously confirmed by x‐ray crystallography. The 1H and 13C NMR spectra of all compounds were assigned using one‐ and two‐dimensional NMR techniques (APT, DEPT, 1D NOE difference, COSY, NOESY, HETCOR, gHMQC and gHMBC). Copyright © 2004 John Wiley & Sons, Ltd.
51V magic angle spinning NMR in VOPO4 phases
Authors: Siegel Renée , Dupré Nicolas , Quarton Michel , Hirschinger Jérôme
Published: September 2004

51V magic angle spinning NMR was applied to the αII, β and γ phases of VOPO4 at three magnetic field strengths (4.7, 7.1, and 11.7 T). The 51V quadrupole and chemical shift tensors were determined by iterative fitting of the NMR lineshapes at the three magnetic field strengths. The applicability of the method is illustrated by comparison with literature data. Although determined chemical shift tensors are completely axially symmetric and of the same magnitude, all studied phases can clearly be distinguished by their quadrupole coupling tensor. Relationships between the 51V NMR data and structural characteristics such as crystal symmetries are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
High‐resolution solid‐state 73Ge NMR spectra of hexacoordinated germanium compounds
Authors: Takeuchi Yoshito , Nishikawa Miki , Yamamoto Hiroshi
Published: September 2004

High‐resolution solid‐state magic angle spinning 73Ge NMR spectra of hexavalent germanium compounds, i.e. diiodogermylene (1a) and bis(1‐pyrrolyl)(meso‐tetraphenylporphyrinato)germanium (3a), were determined. To the best of our knowledge, this is the first example of high‐resolution solid‐state 73Ge NMR spectra of hexacoordinated germanium nuclei. The symmetry requirement for observation of high‐resolution solid‐state 73Ge NMR spectra is discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Creatinine and creatininium cation in DMSO‐d6 solution. Structure and restricted internal rotation of NH2 group
Authors: Kotsyubynskyy Dmytro , Molchanov Sergey , Gryff‐Keller Adam
Published: September 2004

Investigation of 15N NMR spectra of isotopically enriched creatinine has unequivocally shown that in DMSO‐d6 solution it exists as amino tautomer (2‐amino‐1‐methylimidazoline‐4‐one), which in the presence of acid is protonated at N‐3. Free energies of activation of the amino group rotation in creatinine and its cation have been determined to be 56 kJ/mol and 60 kJ/mol, respectively, at 298 K, by performing the simultaneous analysis of the lineshapes of NH2 proton signals in the whole set of 1H NMR spectra recorded at various temperatures and magnetic fields. These results have been theoretically reproduced by the calculations of molecular structures and energies of creatinine and creatininium cation in their ground states and transition states of the amino group rotation, using DFT (B3LYP) method, involving the influence of the solvent. Copyright © 2004 John Wiley & Sons, Ltd.
1H chemical shifts in NMR. Part 21—Prediction of the 1H chemical shifts of molecules containing the ester group: a modelling and ab initio investigation
Authors: Abraham Raymond J. , Bardsley Ben , Mobli Mehdi , Smith Richard J.
Published: September 2004

The 1H NMR spectra of 24 compounds containing the ester group are given and assigned. These data were used to investigate the effect of the ester group on the 1H chemical shifts in these molecules. These effects were analysed using the CHARGE model, which incorporates the electric field, magnetic anisotropy and steric effects of the functional group for long‐range protons together with functions for the calculation of the two‐ and three‐bond effects. The effect of the ester electric field was given by considering the partial atomic charges on the three atoms of the ester group. The anisotropy of the carbonyl group was reproduced with an asymmetric magnetic anisotropy acting at the midpoint of the carbonyl bond with values of Δχparl and Δχperp of 10.1 × 10−30 and −17.1 × 10−30 cm3 molecule−1. An aromatic ring current (=0.3 times the benzene ring current) was found to be necessary for pyrone but none for maleic anhydride. This result was confirmed by GIAO calculations. The observed 1H chemical shifts in the above compounds were compared with those calculated by CHARGE and the ab initio GIAO method (B3LYP/6–31G**). For the 24 compounds investigated with 150 1H chemical shifts spanning a range of ca 10 ppm, the CHARGE model gave an excellent r.m.s. error (obs − calc) of <0.1 ppm. The GIAO calculations gave a very reasonable r.m.s. error of ca 0.2 ppm although larger deviations of ca 0.5 ppm were observed for protons near to the electronegative atoms. The accurate predictions of the 1H chemical shifts given by the CHARGE model were used in the conformational analysis of the vinyl esters methyl acrylate and methyl crotonate. An illustration of the use of the CHARGE model in the prediction of the 1H spectrum of a complex organic molecule (benzochromen‐6‐one) is also given. Copyright © 2004 John Wiley & Sons, Ltd.
Towards the automatic analysis of 1H NMR spectra: Part 4—Additional requirements of flow‐NMR
Authors: Griffiths Lee , Horton Rob
Published: September 2004

Flow‐NMR allows more rapid and convenient acquisition of NMR spectra. Its main application area has therefore been in multiple parallel synthesis or combinatorial chemistry. At the same time, there is a significant need to automate the analysis of the resultant spectra. However, flow‐NMR brings spectral imperfections, which compromise attempts to automate this analysis. This study proposes experimental and computational expedients to accommodate the effects of residual solvent peaks, 13C satellites, finite signal‐to‐noise ratio, impurities, presaturation on integral calculations, the ‘silent’ region and how multiplet areas can be scaled to numbers of protons in this environment. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of proteins regulated by interferon‐α in resistant and sensitive malignant melanoma cell lines
Authors: Craven Rachel A. , Stanley Anthea J. , Hanrahan Sarah , Totty Nick , Jackson David P. , Popescu Razvan , Taylor Allen , Frey Jürgen , Selby Peter J. , Patel Poulam M. , Banks Rosamonde E.
Published: September 2004

Treatment of patients with malignant melanoma with interferon‐α achieves a response in a small but significant subset of patients. Currently, although much is known about interferon biology, little is known about either the particular mechanisms of interferon‐α activity that are crucial for response or why only some patients respond to interferon‐α therapy. Two melanoma cell lines (MeWo and MM418) that are known to differ in their response to the antiproliferative activity of interferon‐α, have been used as a model system to investigate interferon‐α action. Using a proteomics approach based on two‐dimensional polyacrylamide gel electrophoresis and mass spectrometry, several proteins induced in response to interferon‐α have been identified. These include a number of gene products previously known to be type I interferon responsive (tryptophanyl tRNA synthetase, leucine aminopeptidase, ubiquitin cross‐reactive protein, gelsolin, FUSE binding protein 2 and hPNPase) as well as a number of proteins not previously reported to be induced by type I interferon (cathepsin B, proteasomal activator 28α and α‐SNAP). Although the proteins upregulated by interferon‐α were common between the cell lines when examined at the level of Western blotting, the disparity in the basal level of cathepsin B was striking, raising the possibility that the higher level in MM418 may contribute to the sensitivity of this cell line to interferon‐α treatment.
Comparative proteome analysis of differentially expressed proteins induced by K+ deficiency in Arabidopsis thaliana
Authors: Kang Jeong Gu , Pyo Young Jae , Cho Jin Won , Cho Myeon Haeng
Published: September 2004

Mineral nutrient deficiencies constitute major limitations for plant growth on agricultural soils around the world. To identify genes that possibly play roles in plant K+ nutrition, we employed the comparative proteome analysis for proteins isolated from Arabidopsis seedlings treated with K+ deficiency for 3 h and 7 d. We identified genes including those encoding putative transcription factors, protein kinases, and phosphatases, proteins involved in phytohormone biosynthesis or signaling, proteins involved in carbon and energy metabolism, and other proteins possibly involved in signal transduction pathway such as 14‐3‐3 proteins and small G‐protein. Our results suggest that those proteins may play roles in signal transduction pathways linking changes in extracellular K+ status to alterations in gene expression facilitating K+ homeostasis. These results yield a comprehensive picture of the post‐transcriptional response for deprivation of K+ and serve as a basic platform for further characterization of gene function and regulation in plant mineral nutrition.
A simple pattern classification method for alcohol‐responsive proteins that are differentially expressed in mouse brain
Authors: Park Bokyung , Jeong Seul‐Ki , Lee Won‐Suk , Seong Je Kyung , Paik Young‐Ki
Published: September 2004

Proteomic analysis of brain tissues obtained from two inbred mice, C57BL/6J (B6, an alcohol‐preferring strain) and DBA/2J (D2, an alcohol‐avoiding strain), that were orally administered 1.5 g/kg ethanol, was performed to investigate alcohol‐responsive proteins. To analyze relationships of alcohol‐responsive protein spots between B6 and D2 mice, we have developed a simple spot classification method (SCM) for the fully matched spot data sets produced by the Melanie 4 analysis software using the paired two‐dimensional (2‐D) gels of two strains over time. By applying SCM, 55 protein spots that were differentially expressed in brain tissue were classified into 16 patterns as mirror images (2×8 patterns), and additionally in an ordered fashion such as ‘fast turn over’ and ‘slow turn over’ forms, depending on the frequency of repetition and rate of changed expression profile in 2‐D gels over time. Searching for any interaction proteins through databases of interacting proteins using the classified data set has led to the construction of a linkage map, which reveals the interrelationship of the alcohol‐responsive proteins between different species. Thus, it is suggested that the different responses for alcohol between B6 and D2 may come from differences of the response rates and interactions of different variants of the alcohol‐responsive protein family.
Differential expression profiling of the proteomes and their mRNAs in porcine white and red skeletal muscles
Authors: Kim Nam‐Kuk , Joh Joong‐Ho , Park Hye‐Ran , Kim Oun‐Hyun , Park Beom‐Young , Lee Chang‐Soo
Published: September 2004

Skeletal muscle is an heterogeneous tissue with various biochemical and physical properties of several fiber types. In this study, we carried out the comparative study of protein expression patterns in white and red muscles using two‐dimensional gel electrophoresis (2‐DE). From more than 500 protein spots detected on each 2‐DE gel, we screened five proteins that were differentially expressed between white and red muscles. Using peptide mass fingerprint and tandem mass spectrometry analysis these proteins were identified as myoglobin, two slow‐twitch isoforms of myosin light chain and two small heat shock proteins (HSP20 and HSP27). The protein levels of myoglobin, myosin light chain and HSP20 were higher in red muscle, whereas HSP27 was higher in white muscle. In addition, genes of the identified proteins were cloned and their mRNAs were examined. Positive correlations between protein content and their mRNA levels were observed in white and red muscle. These results may provide us with valuable information to understand the different expression profiling between white and red muscle at the protein level.
Regiocontrolled synthesis of poly(3‐alkylthiophene)s by Grignard metathesis
Authors: Mao Yuxia , Wang Yu , Lucht Brett L.
Published: September 2004

Poly(3‐octadecylthiophene)s (P3OTs) were prepared via Grignard metathesis polymerization of 2,5‐dibromo‐3‐octadecylthiophene in the presence of palladium and nickel catalysts. The effect of catalyst structure and reaction temperature on the regioregularity of P3OTs was investigated. Nickel catalysts provided P3OTs with higher regioregularity, while palladium catalysts gave lower regioregularity. Surprisingly, the regioregularity of P3OTs increased when the polymerization was conducted at higher temperature. The catalyst and temperature dependence of the regioregularity is consistent with two competing mechanisms. Polymerizations at higher temperature with nickel catalysts occur primarily via chain‐growth reactions, while polymerizations at lower temperature with palladium catalysts have competing step‐growth and chain growth reactions. P3OTs with higher regioregularity have longer wavelength visible absorptions, while P3OTs with lower regioregularity have shorter wavelength absorptions. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5538–5547, 2004
Kinetic analysis of styrene atom transfer radical polymerization: Extraction of radical‐radical termination rate coefficients
Authors: Shipp Devon A. , Yu Xiang
Published: September 2004

Kinetic studies of the atom transfer radical polymerization (ATRP) of styrene are reported, with the particular aim of determining radical‐radical termination rate coefficients (). The reactions are analyzed using the persistent radical effect (PRE) model. Using this model, average radical‐radical termination rate coefficients are evaluated. Under appropriate ATRP catalyst concentrations,  values of approximately 2 × 108 L mol−1 s−1 at 110 °C in 50 vol % anisole were determined. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5548–5558, 2004
Synthesis and thermal crosslinking of benzophenone‐modified poly(dimethylsiloxane)s
Authors: Mabry Joseph M. , Weber William P.
Published: September 2004

Dihydridocarbonyltris(triphenylphosphine)ruthenium catalyzes the regiospecific anti‐Markovnikov addition of an ortho CH bond of benzophenone across the CC double bonds of α,ω‐bis(trimethylsilyloxy)copoly(dimethylsiloxane/vinylmethylsiloxane) (99:1), α,ω‐bis(vinyldimethylsilyloxy)poly(dimethylsiloxane), and 1,3‐divinyltetramethyldisiloxane to yield α,ω‐bis(trimethylsilyloxy)copoly[dimethylsiloxane/2‐(2′‐benzophenonyl)ethylmethylsiloxane]), α,ω‐bis[2‐(2′‐benzophenonyl)ethyldimethylsilyloxy]poly(dimethylsiloxane), and 1,3‐bis[2‐(2′‐benzophenonyl)ethyl]tetramethyldisiloxane, respectively. These materials have been characterized with 1H, 13C, and 29Si NMR and IR spectroscopy. Their molecular weight distributions have been determined by gel permeation chromatography. The thermal stability of the polymers has been measured by thermogravimetric analysis, and their glass‐transition temperatures (Tg's) have been determined by differential scanning calorimetry. The molecular weight distribution, thermal stability, and Tg's of the modified polysiloxanes are similar to those of the precursor polymers. The molecular weights of these materials can be significantly increased via heating to 300 °C for 1 h. This may be due to crosslinking, by pyrocondensation, of pendant anthracene groups, which are produced by the pyrolysis of the attached ortho‐alkyl benzophenones. UV spectroscopy of the pyrolysate of 1,3‐bis[2‐(2′‐benzophenonyl)ethyl]tetramethyldisiloxane has confirmed the presence of pendant anthracene groups. Thermal crosslinking by the pyrocondensation of pendant anthracene groups has been verified by the pyrolysis of α,ω‐bis(trimethylsilyloxy)copoly[dimethylsiloxane/2‐(9′‐anthracenyl)ethylmethylsiloxane] (97:3). © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5514–5522, 2004
Synthesis and thermal and spectroscopic properties of macrocyclic vinyl aromatic polymers
Authors: Chen Rong , Nossarev Gennadi G. , Hogen‐Esch Thieo E.
Published: September 2004

Well‐defined and narrow molecular weight distribution macrocyclic poly(2‐vinylnaphthalene) (P2VN) and poly(2‐vinyl‐9,9‐dimethylfluorene) (PDMVF) containing a single 1,4‐benzylidene or 9,10‐anthracenylidene unit have been synthesized via the potassium naphthalide initiated polymerization of the monomers followed by the end‐to‐end coupling of the resulting P2VN dianions under high‐dilution conditions with 1,4‐bis(bromomethyl)benzene or 9,10‐bis(chloromethyl)anthracene. Molecular characterization has been carried out by size exclusion chromatography, nuclear magnetic resonance, differential scanning calorimetry, ultraviolet–visible spectroscopy, and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. The thermal properties show distinct differences between the cyclic and matching linear polymers, with the macrocycles showing much higher glass‐transition and decomposition temperatures. The absorption bands are both hyperchromic and hypochromic with respect to the model aromatic compounds, and this is consistent with intensity borrowing. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 5488–5503, 2004
Reaction‐induced phase separation in epoxy/polysulfone/poly(ether imide) systems. II. Generated morphologies
Authors: Giannotti M. I. , Mondragon I. , Galante M. J. , Oyanguren P. A.
Published: September 2004

Epoxy–aromatic diamine formulations are simultaneously modified with two immiscible thermoplastics (TPs), poly(ether imide) (PEI) and polysulfone (PSF), in concentrations ranging from 5 to 15 wt %. The epoxy monomer is based on diglycidyl ether of bisphenol A and the aromatic diamines (ADs) are either 4,4′‐diaminodiphenylsulfone (DDS) or 4,4′‐methylenebis(3‐chloro 2,6‐diethylaniline) (MCDEA). Using phase diagrams developed in Part I of this series, thermal cycles are selected to generate different morphologies. It is found that, whatever the AD employed, a particulate morphology is obtained when curing blends that are initially homogeneous. In the case of DDS‐cured blends, a unimodal particle size distribution of PSF and PEI dispersed in a continuous epoxy‐rich phase is observed. By contrast, the MCDEA‐cured blends show a bimodal particle size distribution for all PSF/PEI relations that are analyzed. A completely different morphology, characterized by a distribution of irregular TP‐rich domains dispersed in an epoxy‐rich phase (double phase morphology), is obtained when curing blends that are initially immiscible. An X‐ray analysis of the different phases makes it possible to determine their qualitative composition. The dynamic mechanical behavior of fully cured blends is also discussed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3964–3975, 2004
Fully exfoliated layered silicate epoxy nanocomposites
Authors: Chen Chenggang , Tolle Tia Benson
Published: September 2004

Fully exfoliated layered silicate epoxy nanocomposites are reported in this article. The processing route that resulted in these fully exfoliated layered silicate epoxies is based on a combination of high‐shear mixing in the presence of acetone and ultrasonication. Homomogeneous and random dispersion of the individual silicate nanolayers in the epoxy is confirmed through transmission electron microscopy images spanning low to high magnification as well as by X‐ray diffraction. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3981–3986, 2004
Diffusion constants of polymers in mixed solvents
Authors: Negadi A. , Benmouna M. , Vilgis T.A.
Published: September 2004

Dynamics of polymers in mixed solvents are investigated on the basis of linear response theory and mean field arguments. Particular attention is given to the coupling between polymer and fluid fluctuations. This coupling is enhanced by polymer–solvent interaction asymmetry and mixed solvent incompatibility. Cooperative and fluid diffusion constants are analyzed in terms of the interactions in the medium and some predictions for light scattering experiments are made. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3976–3980, 2004
The role of age at the onset of cancer in relation to survivors' long‐term adjustment: A controlled comparison over an eight‐year period
Authors: Schroevers Maya J. , Ranchor Adelita V. , Sanderman Robbert
Published: September 2004

The goal of the study was to explore the role of age in survivors' long‐term adjustment to cancer (n=155). Data, both quantitative and qualitative, was assessed at 3 months, 15 months, and 8 years after diagnosis. A reference group from the general population (n=120) was included to be able to distinguish the effects of cancer from those of aging. The findings showed that, in the first year after diagnosis, survivors' physical functioning (especially in those aged 45–65 years) was strongly affected by cancer. In the long term, their physical functioning was more affected by aging. Regarding psychological functioning, survivors younger than 65 years reported more depressive symptoms than similar‐aged references, but only at 3 months after diagnosis. In the long term, younger survivors reported more cancer‐related thoughts and a greater search for meaning in the cancer experience than older survivors. Overall, the findings provide an intriguing description of the complex and interwoven processes of age and aging in the process of adjustment to cancer. Copyright © 2004 John Wiley & Sons, Ltd.
Fertility issues for young adult survivors of childhood cancer
Authors: Zebrack Brad J. , Casillas Jacqueline , Nohr Lindsay , Adams Heidi , Zeltzer Lonnie K.
Published: September 2004

Background. The effects of cancer and its treatment on reproduction and fertility are well‐documented, yet knowledge of the psychosocial and behavioral ramifications of these outcomes for young adult survivors of childhood cancer is limited. As a qualitative exploratory study, this work identifies concerns, attitudes, and behaviors that may be associated with childhood cancer survivors' reproductive capacity.

Procedure. As part of a semi‐structured interview assessing the impact of cancer on long‐term survivors' quality of life, a convenience sample of 32 childhood cancer survivors between the ages of 19–37 and at least five years beyond diagnosis were asked if they had physical limitations as a result of their cancer or treatment, and if having cancer has affected their ability to have children.

Results. These data are organized around two major themes: (1) survivors' reproductive capacity and (2) their attitudes, experiences and concerns about children and parenting. Fifty‐nine percent of survivors reported that they are uncertain about their fertility status, and half recall a parent or health care provider ever mentioning potential reproductive problems associated with their past cancer treatment.

Conclusions. While some survivors profess to know nothing about their risks for infertility, others possess and recall information that influences their personal relationships, their beliefs about having children, and possibly subsequent decisions and behaviors with regard to having children. Copyright © 2004 John Wiley & Sons, Ltd.
Effect of binary combination of some plant‐derived molluscicides with MGK‐264 or piperonyl butoxide on the reproduction of the snail Lymnaea acuminata
Authors: Singh Priyamvada , Singh Vinay K , Singh Dinesh K
Published: September 2004

The effects of sub‐lethal treatments (20 and 60% of 24‐h LC50) with plant‐derived molluscicides Annona squamosa, acetogenins, Argemone mexicana seed and protopine, in combination (1 + 5) with MGK‐264 (ENT 8184) or piperonyl butoxide on the reproduction of Lymnaea acuminata has been studied. The plant‐derived molluscicides and their active molluscicidal components, protopine and acetogenins, in combination with ENT 8184 or piperonyl butoxide caused a significant reduction in the fecundity, hatchability and survival of young snails. Combination of A squamosa seed powder with piperonyl butoxide was very effective as it caused a complete arrest of snail fecundity within 24 h of treatment. Removal of the snails to fresh water after the 96‐h treatments caused a significant recovery in the fecundity of L acuminata. Copyright © 2004 Society of Chemical Industry
Movement and biological activity of drip‐applied 1,3‐dichloropropene and chloropicrin in raised mulched beds in the southeastern USA
Authors: Desaeger Johan AJ , Eger Joe E , Csinos Alex S , Gilreath James P , Olson Steve M , Webster Theodore M
Published: September 2004

Movement and biological activity of 1,3‐dichloropropene (1,3‐D) and chloropicrin applied through drip irrigation in raised beds was investigated at three locations in the southeastern USA. Tests were conducted in fields with dense populations of nutsedge (Cyperus spp), with one location also having a high level of soil nematodes, both of which served as biological indicators of the distribution of effective concentrations of 1,3‐D and chloropicrin. Objectives were (1) to gain a better understanding of 1,3‐D and chloropicrin movement and the extent of biological activity outside of the wetted bed area, and (2) to examine the effect of application rate, application concentration and subsequent irrigation events on movement and activity of 1,3‐D and chloropicrin. InLine®, an emulsifiable concentrate containing 60.8% w/w 1,3‐D and 33.3% w/w chloropicrin, was injected into polyethylene mulched beds through the drip tubes and water movement in the beds was visualized by adding a blue dye to the injection system. Gas concentrations of 1,3‐D and chloropicrin in soil were measured using Gastec® detection tubes at different positions relative to the drip tube at 1–4 days after InLine application. After one week, mulch was removed and nutsedge survival evaluated at different positions in the bed. High concentrations of 1,3‐D and chloropicrin were measured at the bed center and midway between the bed center and the shoulder, but concentrations were low at the bed shoulder. Width of nutsedge control was significantly greater than width of water movement. Plant‐parasitic nematodes were controlled over the entire bed width, but nutsedge re‐emerged at the bed shoulders regardless of treatment. Higher application rates and concentrations of 1,3‐D + chloropicrin resulted in higher fumigant concentrations in soil air. Irrigations subsequent to application reduced soil air concentrations of 1,3‐D and chloropicrin and increased water movement, as did the use of two drip tubes instead of one. The data show that the pesticidal activity of 1,3‐D + chloropicrin extends beyond the waterfront and indicate a significant degree of fumigant activity of emulsifiable 1,3‐D + chloropicrin. However, unlike plant‐parasitic nematodes, nutsedge could not be controlled over the entire bed width, regardless of rate, concentration and volume of water applied. Copyright © 2004 Society of Chemical Industry
Degradation of atrazine and isoproturon in surface and sub‐surface soil materials undergoing different moisture and aeration conditions
Authors: Issa Salah , Wood Martin
Published: September 2004

The influence of different moisture and aeration conditions on the degradation of atrazine and isoproturon was investigated in environmental samples aseptically collected from surface and sub‐surface zones of agricultural land. The materials were maintained at two moisture contents corresponding to just above field capacity or 90% of field capacity. Another two groups of samples were adjusted with water to above field capacity, and, at zero time, exposed to drying–rewetting cycles. Atrazine was more persistent (t1/2 = 22–35 days) than isoproturon (t1/2 = 5–17 days) in samples maintained at constant moisture conditions. The rate of degradation for both herbicides was higher in samples maintained at a moisture content of 90% of field capacity than in samples with higher moisture contents. The reduction in moisture content in samples undergoing desiccation from above field capacity to much lower than field capacity enhanced the degradation of isoproturon (t1/2 = 9–12 days) but reduced the rate of atrazine degradation (t1/2 = 23–35 days). This demonstrates the variability between different micro‐organisms in their susceptibility to desiccation. Under anaerobic conditions generated in anaerobic jars, atrazine degraded much more rapidly than isoproturon in materials taken from three soil profiles (0–250 cm depth). It is suggested that some specific micro‐organisms are able to survive and degrade herbicide under severe conditions of desiccation. Copyright © 2004 Society of Chemical Industry
Experimental study on the toxicity of imidacloprid given in syrup to honey bee (Apis mellifera) colonies
Authors: Faucon Jean‐Paul , Aurières Clément , Drajnudel Patrick , Mathieu Laeticia , Ribière Magali , Martel Anne‐Claire , Zeggane Sarah , Chauzat Marie‐Pierre , Aubert Michel FA
Published: September 2004

Two groups of eight honey bee colonies were fed with two different concentrations of imidacloprid in saccharose syrup during summer (each colony was given 1 litre of saccharose syrup containing 0.5 µg litre−1 or 5 µg litre−1 of imidacloprid on 13 occasions). Their development and survival were followed in parallel with control hives (unfed or fed with saccharose syrup) until the end of the following winter. The parameters followed were: adult bee activity (number of bee entering the hive and pollen carrying activity), adult bee population level, capped brood area, frequency of parasitic and other diseases, mortality, number of frames with brood after wintering and a global score of colonies after wintering. The only parameters linked to feeding with imidacloprid‐supplemented saccharose syrup when compared with feeding with non‐supplemented syrup were: a statistically non‐significant higher activity index of adult bees, a significantly higher frequency of pollen carrying during the feeding period and a larger number of capped brood cells. When imidacloprid was no longer applied, activity and pollen carrying were re‐established at a similar level for all groups. Repeated feeding with syrup supplemented with imidacloprid did not provoke any immediate or any delayed mortality before, during or following the next winter, whereas such severe effects are described by several French bee keepers as a consequence of imidacloprid use for seed dressing in neighbouring cultures. In any case, during the whole study, mortality was very low in all groups, with no difference between imidacloprid‐fed and control colonies. Further research should now address several hypotheses: the troubles described by bee keepers have causes other than imidacloprid; if such troubles are really due to this insecticide, they may only be observed either when bees consume contaminated pollen, when no other sources of food are available, in the presence of synergic factors (that still need to be identified), with some particular races of bees or when colonies are not strong and healthy. Copyright © 2004 Society of Chemical Industry
Parametric accelerated failure time models with random effects and an application to kidney transplant survival
Authors: Lambert Philippe , Collett Dave , Kimber Alan , Johnson Rachel
Published: September 2004

Accelerated failure time models with a shared random component are described, and are used to evaluate the effect of explanatory factors and different transplant centres on survival times following kidney transplantation. Different combinations of the distribution of the random effects and baseline hazard function are considered and the fit of such models to the transplant data is critically assessed. A mixture model that combines short‐ and long‐term components of a hazard function is then developed, which provides a more flexible model for the hazard function. The model can incorporate different explanatory variables and random effects in each component. The model is straightforward to fit using standard statistical software, and is shown to be a good fit to the transplant data. Copyright © 2004 John Wiley & Sons, Ltd.
Post‐transcriptional regulation of the psbA gene family in the cyanobacterium Synechococcus sp. PCC 7942
Authors: Tyystjärvi Taina , Sirpiö Sari , Aro Eva-Mari
Published: September 2004

In the cyanobacterium Synechococcus sp. PCC 7942, the photosystem II reaction center protein D1 is encoded by three psbA genes. The psbAI gene encodes the D1:1 protein that is the prevailing form under steady state conditions, whereas the expression of the psbAII and psbAIII genes, encoding the D1:2 protein, is enhanced under many stress conditions. Here, we show that in addition to transcriptional control, the synthesis of D1 protein forms is regulated at the levels of membrane targeting of psbA mRNA ribosome complexes and translation elongation, whereas the formation of translation initiation complexes does not have a significant regulatory role.
Effect of lipids with different spontaneous curvature on the channel activity of colicin E1: evidence in favor of a toroidal pore
Authors: Sobko Alexander A. , Kotova Elena A. , Antonenko Yuri N. , Zakharov Stanislav D. , Cramer William A.
Published: September 2004

The channel activity of colicin E1 was studied in planar lipid bilayers and liposomes. Colicin E1 pore‐forming activity was found to depend on the curvature of the lipid bilayer, as judged by the effect on channel activity of curvature‐modulating agents. In particular, the colicin‐induced trans‐membrane current was augmented by lysophosphatidylcholine and reduced by oleic acid, agents promoting positive and negative membrane curvature, respectively. The data obtained imply direct involvement of lipids in the formation of colicin E1‐induced pore walls. It is inferred that the toroidal pore model previously validated for small antimicrobial peptides is applicable to colicin E1, a large protein that contains ten α‐helices in its pore‐forming domain.
A modified mammalian tandem affinity purification procedure to prepare functional polycystin‐2 channel
Authors: Li Qiang , Dai Xiao-Qing , Shen Patrick Y. , Cantiello Horacio F. , Karpinski Edward , Chen Xing-Zhen
Published: September 2004

The tandem affinity purification (TAP) procedure was initially developed as a tool for rapid purification of native protein complexes expressed at their natural levels in yeast cells. This purification procedure was also applied to study interactions between soluble proteins in mammalian cells. In order to apply this procedure to mammalian membrane proteins, we created a modified TAP tag expression vector and fused with the PKD2 gene, encoding a membrane cation channel protein, polycystin‐2, mutated in 15% of autosomal dominant polycystic kidney disease. We generated epithelial Madin–Darby canine kidney cell line stably expressing TAP‐tagged polycystin‐2, improved the subsequent steps for membrane protein release and stability, and succeeded in purifying this protein. Using patch clamp electrophysiology, we detected specific polycystin‐2 channel activities when the purified protein was reconstituted into a lipid bilayer system. Thus, this modified TAP procedure provides a powerful alternative to functionally characterize membrane proteins, such as ion channels, transporters and receptors, using cell‐free system derived from mammalian cells.
Production of maltodextrin 1‐Phosphate byFibrobacter succinogenesS85
Authors: Nouaille Régis , Matulova Maria , Delort Anne-Marie , Forano Evelyne
Published: September 2004

We show for the first time the occurrence of maltodextrin‐1‐Phosphate (MD‐1P) (DP ⩾ 2) inF. succinogenesS85, a rumen bacterium specialized in cellulolysis which is not able to use maltose and starch. MD‐1Pwere found in intra and extracellular medium of resting cells incubated with glucose. We used 2D1H NMR technique and TLC to identify their structure and quantify their production with time. It was also shown that these phosphorylated oligosaccharides originated both from exogenous glucose and endogenous glycogen.
Potential bias in estimates of the size of maturity of crabs derived from trap samples
Authors: Smith Kim D. , Hall Norman G. , de Lestang Simon , Potter Ian C.
Published: September 2004

The size at the onset of sexual maturity (SOM) of female crustaceans is typically estimated using logistic regression analysis of the proportions of mature females in sequential size classes. The validity of this approach depends on the composition of the samples reflecting accurately that present in the environment. However, catches obtained by traps, a passive fishing method, typically contain disproportionately greater numbers of large crabs, whereas those obtained using active fishing methods, such as seine-netting and otter trawling, will presumably represent far better the size composition of the population. Moreover, we demonstrate that samples of female Portunus pelagicus caught by trapping were predominantly mature, whereas those collected by seining and trawling contained numerous immature as well as mature females. Therefore, the samples of females collected by trap are clearly biased towards mature crabs. Consequently, for any size class, it would be predicted that the proportion of mature females in trap catches will be overestimated, so shifting the logistic curve fitted to the proportions of mature crabs in each size class to the left, and yielding an underestimate of the SOM. This conclusion is substantiated by the fact that the carapace width of female Portunus pelagicus, at which 50% of individuals reach maturity (SOM50), was estimated to be markedly greater when using the proportion of mature females obtained by seine-netting and otter trawling, i.e. 101.1 mm, than by trapping, i.e. 86.1 mm. Data on the size and maturity status of the deep-sea crabs Hypothalassia acerba and Chaceon bicolor are available only from trap catches. From the above data for P. pelagicus, it is considered likely that, through a greater vulnerability of mature females of these species to capture by traps, the respective SOM50s derived for female H. acerba and C. bicolor from trap samples (carapace lengths of 69.7 and 90.5 mm) will be considerable underestimates of the true values.
Cesarean section intraoperative blood loss and mode of placental separation
Authors: Ramadani H.
Published: September 2004

Objective

To investigate whether manual removal of the placenta is associated with significant blood loss compared with spontaneous separation of the placenta during cesarean delivery.

Design

A randomized prospective study of 400 women with normal pregnancies undergoing cesarean delivery at King Abdulaziz University Hospital, Jeddah, Saudi Arabia. Patients were randomly assigned to the study group, (manual placental removal, n=200) or the control group (spontaneous placental separation, n=200). Operative blood loss was assessed by the volumetric and gravimetric methods. Hemoglobin levels were evaluated the third postoperative day and patient's postoperative complications were recorded.

Results

The mean±S.D. amount of blood loss associated with manual and spontaneous removal of the placenta was 713±240 and 669±253 ml, respectively. This difference was statistically significant (P=0.04). There was a postoperative decrease in hemoglobin levels in both groups. Preoperative hemoglobin levels were 11.6±3 g/dl in the study group and 11.2±1.1 g/dl in the control group, and the difference was statistically significant (P=0.006). The postoperative hemoglobin levels at day 3 were 9.0±1.2 g/dl in the study group and 9.9±1.2 g/dl in the control group (P=0.003), also a statistically significant difference. The incidence of endometritis, wound infection, and need for blood transfusion was similar in the two groups.

Conclusion

Manual delivery of the placenta was significantly associated with greater operative blood loss and greater decrease in postoperative hemoglobin levels, but with shorter operative time compared with spontaneous placental separation. No difference in postoperative complications was noted between the groups.