bluuebunny/crossref_metadata_2025 huggingface dataset:
Diastereoselective Synthesis of β‐Amino‐α‐(trifluoromethyl) Alcohols from Homochiral α‐Dibenzylamino Aldehydes
Authors: Andrés José M. , Pedrosa Rafael , Pérez‐Encabo Alfonso
Published: March 2004

Homochiral α‐dibenzylamino aldehydes, prepared from the corresponding α‐amino acids, react with trimethyl(trifluoromethyl)silane in THF at 0 °C to afford, in good yields and dr, β‐amino‐α‐(trifluoromethyl) alcohols; anti diastereomers were formed as major products in the trifluoromethylation reaction whereas syn diastereomers were obtained as single isomers in a two‐step procedure. Swern oxidation of the mixtures formed in the trifluoromethylation leads to the corresponding α‐dibenzylamino trifluoromethyl ketones which undergo diastereoselective reduction with sodium borohydride. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Computational Study on the Effects of Substituents and Functional Groups in the Isomerization of 1‐ and 2‐Substituted Propenes, Acetaldimines, and Aldehydes
Authors: Chuang Chi‐Hsiang , Lien Min‐Hsiung
Published: March 2004

We have performed ab initio molecular orbital calculations on 1‐ and 2‐substituted propenes, acetaldimines, and aldehydes — H3CC(X)=Y and XCH2CH=Y (Y = CH2, NH, O; X = H, CH3, NH2, OH, F) — to investigate the effects that substituents and functional groups have on their isoelectronic (except X = H) tautomerism. Structures for all stationary points (keto forms, enol forms, and transitions states) were optimized at the HF/6−31G**, MP2(full)/6−31G*, and B3LYP/6−31G** levels of theory and were characterized by frequency calculations. We performed intrinsic reaction coordinate (IRC) calculations at the HF/6−31G** level of theory to connect the transition structures with their local minima along the reaction path. In the transition structures, the migrating H4 atom is slightly out of plane, with a dihedral angle H4−C2−C1−Y3 (d4) of < 12°. In the keto−enol and imine−enamine series, the keto forms are thermodynamically more stable than their counterparts by ca. 30 kcal·mol−1 regardless of the site of substitution. In the 2‐substituted propene (Y = CH2) series, the enol forms are lower in energy than the keto forms by ca. 3−10 kcal·mol−1. There is a very good linear correlation between the relative energies and the electronegativity (Pauling scale) of the non‐hydrogen atom in Y of the functional group C=Y; the coefficient of the linear regression ranges from 0.98624 to 0.99963 for the six tautomeric series at the G2 level of theory. We explain the effects that the substituents have on the relative energies in terms of the changes in bond dissociation energies (by means of isodesmic reactions) and the dispersion of the charge through resonance effects (NBO analysis). These “enolization” processes all have rather high activation energies of 56−78 kcal·mol−1 at the G2 levels of theory. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
A Study of the Conjugate Addition of Thionucleophiles to 2(5H)‐Furanones
Authors: Busqué Felix , de March Pedro , Figueredo Marta , Font Josep , González Lluïsa
Published: March 2004

Several new 4‐thio‐4,5‐dihydro‐2(3H)‐furanones were prepared by the conjugate addition reactions of different thioacids, dithioacids, xanthates and dithiocarbamates to 2(5H)‐furanones. When 5‐methyl‐2(5H)‐furanone was used as the electrophilic substrate, the reaction was diastereoselective affording exclusively thecis‐α,β‐disubstituted butanolides. Some adducts were selectively hydrolysed to deliver a free thiol functionality. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
First Evidence for Wheland Intermediates in Azo‐Coupling Reactions − Reactions between 1,3,5‐Tris(dialkylamino)benzene and Arenediazonium Salts
Authors: Boga Carla , Del Vecchio Erminia , Forlani Luciano
Published: March 2004

We have investigated reactions between 1,3,5‐tris(1‐piperidyl)benzene and 1,3,5‐tris(4‐morpholinyl)benzene and 4‐substituted arenediazonium tetrafluoroborate salts, mainly by NMR spectroscopic measurements. The main products are σ complexes (Wheland‐like intermediates) which are formed in almost quantitative yields and are moderately stable compounds. From these covalent complexes, products of the azo‐coupling reaction may be obtained as salts or as free bases. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Efficient FeIII‐Catalyzed Synthesis of Bis(indolyl)methanes in Ionic Liquids
Authors: Ji Shun‐Jun , Zhou Min‐Feng , Gu Da‐Gong , Jiang Zhao‐Qin , Loh Teck‐Peng
Published: March 2004

An efficient synthesis of bis(indolyl)methanes through FeIII‐catalyzed electrophilic substitution reactions of indoles with various aldehydes in ionic liquid is described. It was found that the ionic liquids involving FeCl3·6H2O were the most efficient catalytic systems, and could be simply recycled without significant loss of activity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Synthesis of α‐Hederin, δ‐Hederin, and Related Triterpenoid Saponins
Authors: Plé Karen , Chwalek Martin , Voutquenne‐Nazabadioko Laurence
Published: March 2004

The synthesis of α‐hederin (3‐O‐[α‐L‐rhamnopyranosyl‐(1⇄2)‐α‐L‐arabinopyranosyl]hederagenin, 1), δ‐hederin (3‐O‐(α‐L‐arabinopyranosyl)hederagenin, 3), and three related triterpenoid saponins is described as part of a study of the structure−activity relationships between triterpenoid saponins and hemolytic activity. 4‐Methoxybenzyl α‐L‐arabinopyranoside (11) was synthesized first and then used to prepare the different arabinose acceptors. Glycosylation between the acceptors and 2,3,4‐tri‐O‐benzoyl‐α‐L‐rhamnopyranosyl trichloroacetimidate (20) was performed in excellent yield to give the desired disaccharides. Coupling of the trichloroacetimidate derivatives of the disaccharides to allyl‐ or methylhederagenin gave the protected saponosides in high yields. The saponins and their corresponding methyl esters were then obtained in good to moderate yields after deprotection. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004)
Video compression for multicast environments using spatial scalability and simulcast coding
Authors: Wan Wade K. , Chen Xuemin , Luthra Ajay
Published: March 2004

A common problem with many video transmission applications is the wide range of available bandwidths between the server and different clients. These environments require efficient multicast video service, the capability to transmit and receive the same video sequence at different resolutions. Two approaches to achieve multicast service are scalable coding (dependent bitstream coding) and simulcast coding (independent bitstream coding). One would expect scalable coding to have higher coding efficiency because a scalable coded bitstream can exploit similar information in another bitstream. This reasoning would suggest that multicast implementations should only use scalable coding for maximum coding efficiency. However, this article shows results where simulcast coding has been found to outperform spatial scalability (one type of scalable coding). In this article, methods are described to select between simulcast coding and spatial scalability for multicast video transmission. These techniques can be used to determine the proper multicast coding approach for providing service to clients with different communication links. The methodology described can also be used to construct decision regions to guide more general scenarios or adaptively switch between the two coding approaches. A number of important results were obtained that may be directly applicable to commercial multicast systems. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 331–340, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10065
Macroblock‐based progressive fine granularity scalable video coding
Authors: Wu Feng , Li Shipeng , Sun Xiaoyan , Zeng Bing , Zhang Ya‐Qin
Published: March 2004

A novel highly efficient macroblock‐based progressive fine granularity scalable (MBPFGS) video coding scheme that can optimally balance drifting errors and coding efficiency is proposed in this article. In order to improve coding efficiency, the existing PFGS video coding scheme uses a set of high‐quality references to predict the enhancement layers. However, potential drifting errors may arise because high‐quality references may not always be available at the decoder when channel bandwidth fluctuates. To solve this problem, we first analyze when drifting errors occur and how they will propagate. Then, an iterative model is established to estimate the drifting errors at the encoder. Meanwhile, three new INTER modes are proposed for the coding of macroblocks at the enhancement layers. One of these modes provides an effective and flexible method to reduce the drifting errors at low enhancement bit rates. Furthermore, we present a decision‐making mechanism to select the proper coding mode for each macroblock at the enhancement layers. Experimental results show that the proposed techniques can dramatically reduce drifting errors at low enhancement bit rates, while significantly improving coding efficiency, up to 2.3 dB in average PSNR, compared with MPEG‐4 FGS at moderate or high bit rates. © 2004 Wiley Periodicals, Inc. Int J Imaging Syst Technol 13, 297–307, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ima.10071
Combinatorial problems motivated by comma‐free codes
Authors: Levenshtein Vladimir I.
Published: March 2004

In the paper some combinatorial problems motivated by comma‐free codes are considered. We describe these problems, give the most significant known results and methods used, present some new results and formulate open problems. © 2004 Wiley Periodicals, Inc.
Regulation of the voltage gated K+ channel Kv1.3 by the ubiquitin ligase Nedd4‐2 and the serum and glucocorticoid inducible kinase SGK1
Authors: Henke G. , Maier G. , Wallisch S. , Boehmer C. , Lang F.
Published: March 2004

The stimulation of cell proliferation by insulin like growth factor IGF‐1 has previously been shown to depend on activation of voltage gated K+ channels. The signaling involved in activation of voltage gated K+ channel Kv1.3 includes the phosphatidylinositol‐3 (PI3) protein kinase, 3‐phosphoinositide dependent protein kinase PDK1 and the serum and glucocorticoid inducible kinase SGK1. However, nothing is known about mechanisms mediating the stimulation of Kv1.3 by SGK1. Most recently, SGK1 has been shown to phosphorylate and thus inactivate the ubiquitin ligase Nedd4‐2. The present study has been performed to explore whether the regulation of Kv1.3 involves Nedd4‐2. To this end Kv1.3 has been expressed in Xenopus oocytes with or without coexpression of Nedd4‐2 and/or constitutively active S422DSGK1. In oocytes expressing Kv1.3 but not in water injected oocytes, depolarization from a holding potential of −80 mV to +20 mV triggers rapidly inactivating currents typical for Kv1.3. Coexpression of Nedd4‐2 decreases, coexpression of S422DSGK1 enhances the currents significantly. The effects of either Nedd4‐2 or of SGK1 are abrogated by destruction of the respective catalytic subunits (C938SNedd4‐2 or K127NSGK1). Further experiments revealed that wild type SGK1 and SGK3 and to a lesser extent SGK2 are similarly effective in stimulating Kv1.3 in both, presence and absence of Nedd4‐2. It is concluded that Kv1.3 is downregulated by Nedd4‐2 and stimulates by SGK1, SGK2, and SGK3. The data thus disclose a novel mechanism of Kv1.3 channel regulation. J. Cell. Physiol. 199: 194–199, 2004© 2003 Wiley‐Liss, Inc.
Epidermal growth factor inhibits 14C‐α‐methyl‐d‐glucopyranoside uptake in renal proximal tubule cells: Involvement of PLC/PKC, p44/42 MAPK, and cPLA2
Authors: Jae Han Ho , Yeong Park Ji , Jung Lee Yun , Taub Mary
Published: March 2004

The effect of EGF on 14C‐α‐methyl‐d‐glucopyranoside (α‐MG) uptake and its related signaling pathways were examined in primary cultured rabbit renal proximal tubule cells (PTCs). Epidermal growth factor (EGF) (50 ng/ml) was found to inhibit α‐MG uptake, a distinctive proximal tubule marker. The EGF effect was blocked by AG1478 (an EGF receptor antagonist) or genistein and herbimycin (tyrosine kinase inhibitors), respectively. In addition, the EGF‐induced inhibition of α‐MG uptake was blocked by neomycin and U73122 (phospholipase C inhibitors) as well as staurosporine, H‐7, and bisindolylmaleimide I (protein kinase C inhibitors). EGF was also observed to increase inositol phosphate formation. Furthermore, both the EGF‐induced inhibition of α‐MG uptake and increase of arachidonic acid (AA) release were blocked by AACOCF3 (a cytosolic phospholipase A2 inhibitor), indomethacin (a cyclooxygenase inhibitor), and econazole (a cytochrome P‐450 epoxygenase inhibitor). We examined the involvement of mitogen‐activated protein kinases (MAPKs) in mediating the effect of EGF on α‐MG uptake. Indeed, EGF increased phosphorylation of p44/p42 MAPK and the EGF‐induced inhibition of α‐MG uptake as well as the stimulatory effect of EGF on AA release was blocked by PD 98059 (a p44/42 MAPK inhibitor), suggesting a causal relationship. However, inhibitors of PKC also prevented the EGF‐induced increase of AA release. In conclusion, EGF partially inhibited α‐MG uptake via PLC/PKC, p44/42 MAPK, and PLA2 signaling pathways. J. Cell. Physiol. 199: 206–216, 2004© 2003 Wiley‐Liss, Inc.
CXCL12 chemokine up‐regulates bone resorption and MMP‐9 release by human osteoclasts: CXCL12 levels are increased in synovial and bone tissue of rheumatoid arthritis patients
Authors: Grassi Francesco , Cristino Sandra , Toneguzzi Stefania , Piacentini Anna , Facchini Andrea , Lisignoli Gina
Published: March 2004

Chemokines are involved in a number of inflammatory pathologies and some of them show a pivotal role in the modulation of osteoclast development. Therefore, we evaluated the role of CXCL12 chemokine on osteoclast differentiation and function and we analyzed its expression on synovial and bone tissue biopsies from rheumatoid arthritis (RA) patients. Osteoclasts were obtained by 7 days in vitro differentiation with RANKL and M‐CSF of CD11b positive cells in the presence or absence of CXCL12. The total number of osteoclast was analyzed by Tartrate‐resistant acid phosphatase (TRAP)‐staining and bone‐resorbing activity was assessed by pit assay. MMP‐9 and TIMP‐1 release was evaluated by ELISA assay. CXCL12 expression on biopsies from RA patients was analyzed by immunohistochemistry. Osteoclasts obtained in the presence of CXCL12 at 10 nM concentration displayed a highly significant increase in bone‐resorbing activity as measured by pit resorption assay, while the total number of mature osteoclasts was not affected. The increased resorption is associated with overexpression of MMP‐9. Immunostaining for CXCL12 on synovial and bone tissue biopsies from both rheumatoid arthritis (RA) and osteoarthritis (OA) samples revealed a strong increase in the expression levels under inflammatory conditions. CXCL12 chemokine showed a clear activating role on mature osteoclast by inducing bone‐resorbing activity and specific MMP‐9 enzymatic release. Moreover, since bone and synovial biopsies from RA patients showed an elevated CXCL12 expression, these findings may provide useful tools for achieving a full elucidation of the complex network that regulates osteoclast function in course of inflammatory diseases. J. Cell. Physiol. 199: 244–251, 2004© 2003 Wiley‐Liss, Inc.
SHP‐2 regulates the phosphatidylinositide 3′‐kinase/Akt pathway and suppresses caspase 3‐mediated apoptosis
Authors: Ivins Zito Christina , Kontaridis Maria I. , Fornaro Mara , Feng Geng‐Shen , Bennett Anton M.
Published: March 2004

The Src homology domain 2 (SH2)‐containing tyrosine phosphatase SHP‐2 has been implicated in the regulation of the phosphatidylinositol 3′‐kinase (PI3K)/Akt pathway. The ability of SHP‐2 to regulate the PI3K/Akt pathway is suggested to result in the positive effect of SHP‐2 on cell survival. Whether SHP‐2 regulates insulin‐like growth factor‐1 (IGF‐1)‐dependent activation of Akt at the level of PI3K has yet to be established. Furthermore, the identification of the down‐stream apoptotic target engaged by SHP‐2 in cell survival also has yet to be determined. Here, we show that overexpression of a catalytically inactive mutant of SHP‐2 inhibited insulin‐like growth factor‐1 (IGF‐1)‐dependent PI3K and Akt activation. Consistent with the observation that SHP‐2 participates in pro‐survival signaling fibroblasts expressing a deletion within exon 3 of SHP‐2, which results in a truncation of the amino‐terminus SH2 domain (SHP‐2Ex3−/−), were hypersensitive to etoposide‐induced cell death. SHP‐2Ex3−/− fibroblasts exhibited enhanced levels of etoposide‐induced caspase 3 activity as compared to wild‐type fibroblasts and the enhanced level of caspase 3 activity was suppressed by a caspase 3‐specific inhibitor. Re‐introduction of wild‐type SHP‐2 into the SHP‐2Ex3−/− fibroblasts rescued the hypersensitivity to etoposide‐induced caspase 3 activation. The effects of abrogating SHP‐2 function on cell survival were not specific to the loss of the amino‐terminus SH2 domain of SHP‐2 since RNAi‐mediated knock‐down of SHP‐2 also reduced cell survival. Taken together, these data indicate that the catalytic activity of SHP‐2 is required to regulate the PI3K/Akt pathway and thus likely participates in anti‐apoptotic signaling by suppressing caspase 3‐mediated apoptosis. J. Cell. Physiol. 199: 227–236, 2004© 2003 Wiley‐Liss, Inc.
Genetic characterization of Pompeii and Herculaneum Equidae buried by Vesuvius in 79 AD
Authors: Di Bernardo G. , Galderisi U. , Del Gaudio S. , D'Aniello A. , Lanave C. , De Robertis M.T. , Cascino Antonino , Cipollaro M.
Published: March 2004

DNA extracted from the skeletons of five equids discovered in a Pompeii stable and of a horse found in Herculaneum was investigated. Amino acid racemization level was consistent with the presence of DNA. Post‐mortem base modifications were excluded by sequencing a 146 bp fragment of the 16S rRNA mitochondrial gene. Sequencing of a 370 bp fragment of mitochondrial (mt)DNA control region allowed the construction of a phylogenetic tree that, along with sequencing of nuclear genes (epsilon globin, gamma interferon, and p53) fragments, gave us the possibility to address some questions puzzling archaeologists. What animals—donkeys, horses, or crossbreeds—were they? And, given they had been evidently assigned to one specific job, were they all akin or were they animals with different mitochondrial haplotypes? The conclusions provided by molecular analysis show that the Pompeii remains are those of horses and mules. Furthermore one of the equids (CAV5) seems to belong to a haplotype, which is either not yet documented in the GenBank or has since disappeared. As its characteristics closely recall those of donkeys, which is the out group chosen to construct the tree, that appears to have evolved within the Equidae family much earlier than horses, this assumption seems to be nearer the truth. J. Cell. Physiol. 199: 200–205, 2004© 2003 Wiley‐Liss, Inc.
Requirement of TGF‐β receptor‐dependent activation of c‐Jun N‐terminal kinases (JNKs)/stress‐activated protein kinases (Sapks) for TGF‐β up‐regulation of the urokinase‐type plasminogen activator receptor
Authors: Yue Jianbo , Sun Baodong , Liu Guangming , Mulder Kathleen M.
Published: March 2004

We have previously demonstrated that activation of the Ras/Mapk pathways is required for transforming growth factor β (TGF‐β) induction of TGF‐β1 expression. Here we examined the role of the Ras/Mapk pathways in TGF‐β induction of urokinase‐type plasminogen activator receptor (uPAR) expression in untransformed intestinal epithelial cells (IECs). TGF‐β activated the stress‐activated protein kinases (Sapk)/c‐Jun N‐terminal kinases (JNKs) within 5–10 min, an effect that preceeded TGF‐β induction of uPAR expression in these cells. TGF‐β induction of both JNK1 activity and JunD phosphorylation was blocked by expression of a dominant‐negative mutant of the type II TGF‐β receptor (DN TβRII), a dominant‐negative mutant of MKK4 (DN MKK4), or a dominant‐negative mutant of Ras (RasN17), or by the addition of the JNK inhibitor SP600125. TGF‐β also induced AP‐1 complex formation at the distal AP‐1 site (−184 to −178) of the uPAR promoter within 2 h of TGF‐β addition, consistent with the time‐dependent up‐regulation of uPAR expression. The primary components present in the TGF‐β‐stimulated AP‐1 complex bound to the uPAR promoter were Jun D and Fra‐2. Moreover, addition of SP600125, or expression of DN MKK4 or DN TβRII, blocked TGF‐β up‐regulation of uPAR in IECs. Accordingly, our results indicate that TGF‐β activates the Ras/MKK4/JNK1 signaling cascade, leading to induction of AP‐1 activity, which, in turn, up‐regulates uPAR expression. Our results also indicate that the type II TGF‐β receptor (RII) is required for TGF‐β activation of JNK1 and the resulting up‐regulation of uPAR expression. J. Cell. Physiol. 199: 284–292, 2004© 2003 Wiley‐Liss, Inc.
Meeting report on 3rd National Congress of the Italian society of virology (SIV)
Authors: Salata Cristiano , Palù Giorgio
Published: March 2004

J. Cell. Physiol. 199: 171–173, 2004© 2004 Wiley‐Liss, Inc.
Preparation of sorbitol from D‐glucose hydrogenation in gas–liquid–solid three‐phase flow airlift loop reactor
Authors: Wen Jian‐Ping , Wang Chang‐Lin , Liu Yan‐Xin
Published: March 2004

A new process for D‐glucose hydrogenation in 50 wt% aqueous solution, into sorbitol in a 1.5 m3 gas–liquid–solid three‐phase flow airlift loop reactor (ALR) over Raney Nickel catalysts has been developed. Five main factors affecting the reaction time and molar yield to sorbitol, including reaction temperature (TR), reaction pressure (PR), pH, hydrogen gas flowrate (Qg) and content of active hydrogen, were investigated and optimized. The average reaction time and molar yield were 70 min and 98.6% under the optimum operating conditions, respectively. The efficiencies of preparation of sorbitol between the gas–liquid–solid three‐phase flow ALR and stirred tank reactor (STR) under the same operating conditions were compared. Copyright © 2004 Society of Chemical Industry
Photocatalytic degradation of chlorobenzene using solar and artificial UV radiation
Authors: Bhatkhande Dhananjay S , Sawant Sudhir B , Schouten Jaap C , Pangarkar Vishwas G
Published: March 2004

In this work photocatalytic degradation of chlorobenzene has been studied using solar and artificial UV radiations. The effect of pH and the presence of different anions on the degradation of chlorobenzene has been studied for both cases. Chlorobenzene has been found to be a strongly adsorbing and hence rapidly degrading species when subjected to photocatalysis. The effect of pH in the range of 3–10 and the presence of different anions at a concentration of 0.1 mol dm−3 on the adsorption was studied. Both pH and the presence of anions affect adsorption and the degradation but the overall effect is negligible (<5%). Copyright © 2004 Society of Chemical Industry
Characteristics of aqueous microenvironments in non‐ionic surfactant reverse micelles and their use for enzyme reactions in non‐aqueous media
Authors: Sawada K , Ueda M
Published: March 2004

The polarity of water solubilized in the interior of non‐ionic surfactant reverse micellar systems has been investigated using optical probes. Small amounts of water incorporated on the inside of various reverse micellar systems, polyoxyethylene sorbitan trioleate (Tween‐85)/isopropyl alcohol/n‐hexane mixture and polyoxyethylene tert‐octylphenyl ether (TX‐100)/cyclohexane, were found to have low polarity compared with bulk water. The polarity of water in both Tween‐85 and TX‐100 reverse micellar systems corresponded to that of methanol. The activity of the proteases α‐chymotrypsin and subtilisin in Tween‐85 and TX‐100 reverse micellar systems has also been investigated. It was found that the amounts of water in the reverse micellar system have a significant influence on the activity of enzymes. In the TX‐100 reverse micellar system, neither enzymes showed any activity. In contrast, the activity of enzymes in the Tween‐85 reverse micellar system was similar to that in the aqueous system and followed standard Michaelis–Menten kinetics. Copyright © 2004 Society of Chemical Industry
Enzyme processing of wool fabrics in a non‐ionic surfactant reverse micellar system
Authors: Sawada K , Ueda M
Published: March 2004

Modification of wool fabrics with an enzyme in a reverse micellar system has been investigated using polyoxyethylene sorbitan trioleate as a surfactant. The protease, Bioprase 30L, used in this study was satisfactorily solubilized in the reverse micellar system and maintained its activity even in an organic media. Modification of wool fabrics with Bioprase 30L was evaluated by the fabric's weight loss, measurement of tear strength, scanning electron microscopy, and measurement of shrinkage. Effective modification of wool fabrics with enzymatic hydrolysis can be attained without causing serious loss of fiber strength. Copyright © 2004 Society of Chemical Industry
Synthesis of 1,1‐diethoxyethane using a continuous flow reactor: catalyst deactivation and effect of feed purity and of solvent addition
Authors: Gomez Manuel F , Arrúa Luis A , Abello Ma Cristina
Published: March 2004

The synthesis of 1,1‐diethoxyethane from ethanol and acetaldehyde was studied in a continuous flow reactor using Amberlyst 15 as catalyst. The resin underwent an important activity loss with both analytical quality reagents and industrial raw materials. The deactivation was related to a deterioration in acidity as a consequence of sulfonic group hydration mainly promoted by water from reaction. A higher ethanol conversion and a lower deactivation rate at long time on‐stream were observed when n‐hexane was added to the feed. Copyright © 2004 Society of Chemical Industry
Extraction of zinc from blast‐furnace dust using ammonium sulfate
Authors: Saleh Hesham I , Hassan Kamaleldin M
Published: March 2004

The reaction between roasted zinc blast‐furnace dust (BFD) and ammonium sulfate was studied in the temperature range 250–450 °C using different molar ratios to determine the maximum extraction of zinc. The reaction products are characterized. The composition of the untreated and roasted BFD, and reaction products was investigated by chemical, thermal, X‐ray diffraction and fluorescence analyses. The decomposition of ammonium sulfate leads to the formation of (NH4)2S2O7, NH4HSO4 and (NH4)3H(SO4)3. The main zinc reaction products are ZnSO4, ZnSO3, (NH4)2Zn(SO4)2, (NH4)2Zn2(SO4)3 and (NH4)2Zn4(SO4)5. The reaction mechanisms of these formations are discussed in detail. The identity of these products depends essentially on the temperature as well as the molar ratios of the reactants. The optimum conditions for the formation of soluble zinc compounds are molar ratio 1:8 of roasted zinc dust (ZnO) and (NH4)2SO4 at 350 °C. Under these conditions, up to 95% of zinc was leached with 0.5 M sulfuric acid. Copyright © 2004 Society of Chemical Industry
Efficient production of hydrogen from wastewater sludge
Authors: Wang CC , Chang CW , Chu CP , Lee DJ , Chang Bea‐Ven , Liao CS
Published: March 2004

Efficient production of hydrogen, approximately ten times greater than reported in the literature, could be achieved using Clostridium bifermentans isolated from waste water sludge as inoculum. Copyright © 2004 Society of Chemical Industry
Differential effects of prenyl pyrophosphates on the phosphatase activity of phosphotyrosyl protein phosphatase
Authors: Chen Huei‐chen , Chen Chau‐Huei , chuang Nin‐nin
Published: March 2004

Phosphotyrosyl protein phosphatase (PTPase) 1B was purified from human placenta. Immunoprecipitation analysis revealed that the isolated PTPase 1B appears as a complex with the receptor for protein kinase C (RACK1) and protein kinase C (PKC)δ. The abilities of PTPase 1B and PKCδ to associate with RACK1 were reconfirmed by an in vitro reconstitution experiment. The E. coli expressed and biotinylated mice‐RACK1–encoded fusion protein was capable of recruiting PTPase 1B and PKCδ in the antibiotin immunoprecipitate as a complex of PTPase 1B/RACK1/PKCδ. Thus PTPase 1B enzyme preparation was subjected to further purification by selective binding of PTPase 1B onto PEPTaxol affinity column in the absence of ATP. The purified PTPase 1B enzyme exihibited dose‐dependent phosphatase activity towards [γ–32P]‐ATP labeled mice β‐tubulin‐encoded fusion protein. The dephosphorylation reaction with PTPase 1B was enhanced with geranylgeranyl pyrophosphate, but not with farnesyl pyrophosphate. Interestingly, additional incubation of the purified PTPase 1B enzyme preparation with RACK1, geranylgeranyl pyrophosphate failed to modulate the dephosphorylation activity of PTPase 1B. In contrast, the enhancement effect of farnesyl pyrophosphate on the kinase activity of PKCδ was sustained in the presence of RACK1. That is, farnesyl pyrophosphate may function as a signal to induce the kinase activity of PKCδ in PTPase 1B/RACK1/PKCδ complex but geranylgeranyl pyrophosphate may not for PTPase 1B. J. Exp. Zool. 301A:307–316, 2004. © 2004 Wiley‐Liss, Inc.
Analysis of cerebro‐spinal fluid protein composition in early developmental stages in chick embryos
Authors: Gato A. , Martín P. , Alonso M.I. , Martín C. , Pulgar M.A. , Moro J.A.
Published: March 2004

Foetal cerebro‐spinal fluid (CSF) has a very high protein concentration when compared to adult CSF, and in many species five major protein fractions have been described. However, the protein concentration and composition in CSF during early developmental stages remains largely unknown. Our results show that in the earliest stages (18 to 30 H.H.) of chick development there is a progressive increase in CSF protein concentration until foetal values are attained. In addition, by performing electrophoretic separation and high‐sensitivity silver staining, we were able to identify a total of 21 different protein fractions in the chick embryo CSF. In accordance with the developmental pattern of their concentration, these can be classified as follows: A: high‐concentration fractions which corresponded with the ones described in foetal CSF by other authors; B: low‐concentration fractions which remained stable throughout the period studied; C: low‐concentration fractions which show changes during this period. The evolution and molecular weight of the latter group suggest the possibility of an important biological role. Our data demonstrate that all the CSF protein fractions are present in embryonic serum; this could mean that the specific transport mechanisms in neuroepithelial cells described in the foetal period evolve in very early stages of development. In conclusion, this paper offers an accurate study of the protein composition of chick embryonic CSF, which will help the understanding of the influences on neuroepithelial stem cells during development and, as a result, the appropriate conditions for the in vitro study of embryonic/foetal nervous tissue cells. J. Exp. Zool. 301A:280–289, 2004. © 2004 Wiley‐Liss, Inc.
Traced studies on metabolism of astaxanthin in Atlantic salmon (salmo salar)
Authors: Xu Youqing , Ding Zhaokun
Published: March 2004

The present studies were performed to investigate the metabolism of astaxanthin (Ax) in Atlantic salmon, especially in the liver of salmon. The investigations were undertaken in vivo salmon that were fed a diet containing 60 ppm 15, 15′ 14C‐labelled Ax prior to sacrifice. The samples of blood, bile, liver, gastrointestinal tract and contents, muscle, skin, remaining carcass and feces were taken for scintillation counting. The highest radioactivity (71.36%) of 14C‐labelled Ax was found in the gastrointestinal contents and feces, 7.13% in the bile and 10.68% in the samples of liver, muscle, and skin at the end of the experiments. The metabolites of 14C‐labelled Ax were extracted from the bile of the salmon and analyzed using thin‐layer chromatography (TLC) and high performance liquid chromatography (HPLC). Predominant 14C‐labelled Ax and its cis‐isomers were found and no conjugation of 14C‐labelled Ax was observed. These results indicate that 14C‐labelled Ax was not conjugated into larger colorless compound in Atlantic salmon liver. J. Exp. Zool. 301A: 317–323, 2004. © 2004 Wiley‐Liss, Inc.
Technical aspects of the piezo, laser‐assisted, and conventional methods for nuclear transfer of mouse oocytes and their efficiency and efficacy: Piezo minimizes damage of the ooplasmic membrane at injection
Authors: Chen Shee‐Uan , Chao Kuang‐Han , Chang Chia‐Yi , Hsieh Fon‐Jou , Ho Hong‐Nerng , Yang Yu‐Shih
Published: March 2004

Assessment of the advantages and disadvantages of the piezo, laser, and conventional methods for nuclear transfer has remained elusive. Furthermore, although the piezo method had been used by some investigators for research of sperm injection and nuclear transfer for several years, many researchers have failed to operate the technique smoothly and achieve reproducible results. The procedures of nuclear transfer using piezo were ascertained and described in detail. Mouse oocytes were enucleated, and injected with cumulus cells using the piezo, laser, or conventional methods. We investigated the time needed and survival of nuclear transfer. Development was compared among the three methods and parthenogenetic control specimens. The average time of nuclear transfer for each oocyte was significantly shorter using the piezo (118±9 s) and laser methods (120±11 s) than using the conventional method (170±11 s). The damage rate was smaller for the piezo group (10%) than the laser (37%) and conventional (40%) groups. The percentages of blastocyst formation (14%, 12%, and 11%) and the number of nuclei of blastocysts (54±13, 51±11, and 52±12) were similar among the piezo, laser, and conventional groups, but significantly lower than for the control group (83%, 105±14). The piezo technique is more efficient than the conventional method for nuclear transfer. The laser method is easy to operate, but the equipment is expensive. In addition, piezo induced fewer traumas while breaking the membrane than the aspiration techniques used in the laser and conventional methods. J. Exp. Zool. 301A:344–351, 2004. © 2004 Wiley‐Liss, Inc.
Function of TGF‐β2 in the growth of chicken primordial germ cells and germinal ridge stroma cells during embryonic development
Authors: Fujioka Tsuyoshi , Soh Tomoki , Fujihara Noboru , Hattori Masa‐Aki
Published: March 2004

The development of chicken embryonic gonads is locally regulated by the systematic action of growth factors. Recently, we used suppressive subtraction cloning to identify transforming growth factor β2 (TGF‐β2) as a growth factor gene preferentially expressed in chicken embryonic ovaries and testes during the early periods of development (Hattori et al. 2002a. Prominent expression of transforming growth factor β2 gene in the chicken embryonic gonad as revealed by suppressive subtraction cloning. Gen Comp Endocrinol 125:311–316). In the present study, the function of TGF‐β2 in chicken embryonic gonads was investigated using a serum‐free culture system in the presence of several growth factors, which may behave as mitogenic or survival factors of primordial germ cells (PGCs). Chicken germinal ridges containing PGCs and germinal ridge stroma cells (GRSCs) were collected from six‐day embryos. Addition of TGF‐β2 caused a dose‐dependent inhibition of the number of co‐cultured PGCs and GRSCs in the presence of these growth factors. However, there was no obvious difference between embryonic ovaries and testes in the effects of TGF‐β2. Immunocytochemical analysis using anti‐SSEA–1 antibody revealed that TGF‐β2 induced fragmentation of PGCs. Expression of the TGF‐β2 gene was estimated in the co‐cultured PGCs and GRSCs by semi‐quantitative RT‐PCR. The mRNA level of TGF‐β2 was significantly suppressed in the presence of the growth factors. These results suggest that TGF‐β2 is a gonadal regulator preferentially expressed at the early stages of chicken embryonic development and reduces the growth of PGCs and GRSCs by suppressing proliferation. However, expression of TGF‐β2 may be controlled by mitogenic or survival factors of PGCs. J. Exp. Zool. 301A:290‐296, 2004. © 2004 Wiley‐Liss, Inc.
Effects of peritoneal injection of NH4HCO3 on nitrogen excretion and metabolism in the swamp eel monopterus albus— increased ammonia excretion with an induction of glutamine synthetase activity
Authors: Lim Chiat Koo , Chew Shit Fun , Tay Angeline Su Ling , Ip Yuen Kwong
Published: March 2004

Monopterus albus has to deal with high environmental ammonia concentrations during dry seasons and agricultural fertilization in rice fields. In this study, NH4HCO3 (10 μmol per g fish) was injected into the peritoneal cavity of M. albus, raising the level of ammonia in the body, in order to elucidate the strategies involved in defense against the toxicity of exogenous ammonia. During the subsequent 24 h after NH4HCO3 injection, there was a significant increase in the ammonia excretion rate, which indicates that the main strategy adopted by M. albus was to remove the majority of the exogenous ammonia through enhanced ammonia excretion. Exogenous ammonia was not detoxified into urea for excretion or accumulation. Six hours post‐injection of NH4HCO3, ammonia content in the tissues built up significantly, especially in the brain, which suggests that M. albus had high tolerance of ammonia toxicity at the cellular and sub‐cellular levels. By hour 12 post‐injection, there were significant increases in the activities of glutamine synthetase in the muscle, liver, and gut, accompanied by significant increases in glutamine contents in the muscle and the liver. There was also a significant increase in the glutamine content in the brain at hour 6 post‐injection of NH4HCO3. These results confirm the capability of M. albus to detoxify ammonia through glutamine synthesis. Overall, injection of NH4HCO3 had only minor effects on the contents of FAAs, other than glutamine, in tissues of M. albus because the majority (70%) of the injected ammonia was excreted within the 24–h period. J. Exp. Zool. 301A:324–333, 2004. © 2004 Wiley‐Liss, Inc.
Seasonal concentrations of reproductive steroids in the gonads of the atlantic hagfish, Myxine glutinosa
Authors: Powell Mickle L. , Kavanaugh Scott I. , Sower Stacia A.
Published: March 2004

Changes in gonadal morphology, gonadal estradiol, and progesterone were examined in Atlantic hagfish, Myxine glutinosa, during a period of 17 months, beginning in April, 2001. Atlantic hagfish were captured from the ocean on a monthly basis. A total of 60 hagfish were divided into three different size classes of twenty hagfish each (small 20–35 cm, medium 35–45 cm, large 45–55+cm) and transported to the University of New Hampshire for sampling. Overall, in the medium and large size hagfish, estradiol and progesterone had significantly elevated peaks in January, 2001. There were significant increases in estradiol concentrations in January, with relatively low fluctuations in levels for the rest of the sampling period. Progesterone concentrations increased significantly in January, 2002, in medium and large hagfish, and remained elevated until June and April, 2002, for the two size classes respectively. The majority of hagfish sampled were females or hermaphrodites; few true males were identified in any of the samples. The number of females with large eggs increased following the estradiol peak in January and hermaphrodites with mature sperm were identified in the July, 2002, sample. These data represent the first evidence for a seasonal reproductive cycle in M. glutinosa and only the second seasonal reproductive cycle identified in any hagfish species. J. Exp. Zool. 301A: 352‐360, 2004. © 2004 Wiley‐Liss, Inc.
Localization of vitellogenin mRNA expression and vitellogenin uptake during ovarian maturation in the giant freshwater prawn Macrobrachium rosenbergii
Authors: Jasmani Safiah , Ohira Tsuyoshi , Jayasankar Vidya , Tsutsui Naoaki , Aida Katsumi , Wilder Marcy N.
Published: March 2004

In situ hybridization and immunohistochemical techniques were used to investigate the dynamics of vitellogenin (Vg) mRNA expression and Vg uptake during ovarian maturation in the hepatopancreas and ovary at differing stages of ovarian maturation in both intact and eyestalk ablated female Macrobrachium rosenbergii. In the hepatopancreas of intact animals, Vg mRNA expression was detected faintly two days after ecdysis, and signals showed a gradual increase as the molt cycle advanced to the premolt stages, but decreased at the late premolt stage. Vg mRNA was detected in the R‐cells of the hepatopancreas, indicating that these cells are responsible for synthesizing Vg. No Vg mRNA expression was observed in the ovary. Immunohistochemistry results for the hepatopancreas showed a pattern of staining intensity similar to that of in situ hybridization. Increases in the accumulation of yolk protein in the oocytes occurred concomitantly with increasing Vg mRNA expression. In eyestalk ablated animals, Vg mRNA expression and Vg uptake showed similar but accelerated patterns to those of intact animals. This study has confirmed on the cellular level previous results that Vg synthesis is intrinsically correlated to ovarian maturation and the molt cycle in M. rosenbergii. J. Exp. Zool. 301A:334‐343, 2004. © 2004 Wiley‐Liss, Inc.
Novel probes for imaging amyloid‐β: F‐18 and C‐11 labeling of 2‐(4‐aminostyryl)benzoxazole derivatives
Authors: Shimadzu Hiroshi , Suemoto Takahiro , Suzuki Masako , Shiomitsu Tsuyoshi , Okamura Nobuyuki , Kudo Yukitsuka , Sawada Tohru
Published: March 2004

2‐(4‐Methylaminostyryl)‐6‐(2‐[18F]fluoroethoxy)benzoxazole ([18F]BF‐168) was prepared and found to be a potential probe for imaging amyloid‐β. The precursor, a 6‐(2‐tosyloxyethoxy)benzoxazole derivative, was fluorinated with [18F]KF and Kryptofix 222 in acetonitrile, and the crude product purified by semi‐preparative HPLC to give [18F]BF‐168. The radiochemical purity was >95% and the maximum specific activity was 106 TBq/mmol at the end of synthesis. The synthesis time was 110 min from the end of bombardment.

2‐(4‐[N‐methyl‐11C]methylaminostyryl)‐5‐fluorobenzoxazole ([11C]BF‐145) was also prepared from 2‐(4‐aminostyryl)‐5‐fluorobenzoxazole, [11C]MeI and 5 N NaOH in DMSO, and purified by semi‐preparative HPLC. The radiochemical purity was >95% and the specific activity was 40–70 TBq/mmol at the end of synthesis. The synthesis time was 45 min from the end of bombardment. Copyright © 2004 John Wiley & Sons, Ltd.
Synthesis, radio‐LC‐MS analysis and biological evaluation of 99mTc‐techmazenil
Authors: Kieffer Davy , Cleynhens Bernard , Verbeke Kristin , Vanbilloen Hubert , de Groot Tjibbe , Terwinghe Christelle , Verbruggen Alfons , Bormans Guy
Published: March 2004

A 99mTc‐labelled compound with the biological characteristics of flumazenil would be useful for determination of neuronal viability after the onset of a stroke. Therefore, we have derivatized Ro‐15‐3890 (a flumazenil metabolite bearing a carboxylic acid group instead of an ethyl ester) by coupling it with a bisamino bisthiol tetraligand bearing a 3‐hydroxypropyl side chain (3‐hydroxypropyl‐BAT) to enable labelling with technetium‐99m. After purification by RP‐HPLC, the ligand was deprotected and labelled in a ‘one pot’ reaction, yielding a 99mTc‐BAT‐propylester of Ro‐15‐3890 (99mTc‐techmazenil). Radio‐LC‐MS analysis of the isolated main peak showed the molecular ion mass (608.0618) of the expected 99mTc‐techmazenil. The biodistribution of 99mTc‐techmazenil was investigated in normal mice and indicated that the tracer is cleared from plasma mainly by the hepatobiliary system and shows a very low uptake in brain. In vitro binding studies on mice brain slices indicated that techmazenil does not bind to benzodiazepine receptors. Copyright © 2004 John Wiley & Sons, Ltd.
Mumps epididymo‐orchitis with prolonged detection of virus in semen and the development of anti‐sperm antibodies
Authors: Jalal H. , Bahadur G. , Knowles W. , Jin L. , Brink N.
Published: March 2004

Epididymo‐orchitis is the most common complication of mumps in post‐pubertal men. A case of MMR vaccine failure, in whom mumps and mumps‐associated unilateral epididymo‐orchitis developed, is presented in this article. Mumps virus was isolated from the semen 14 days after onset and mumps RNA was detected in semen for up to 40 days using RT‐PCR. Epididymo‐orchitis was associated with transient but significant reduction in sperm count and severe abnormalities in sperm morphology. It also led to the appearance of anti‐sperm antibodies, which may have potential long‐term adverse effects on the patient's fertility. Sequencing of the SH gene of the virus showed this to be a new mumps genotype distinct from the virus circulating currently in the UK. J. Med. Virol. 73:147–150, 2004. © 2004 Wiley‐Liss, Inc.
LightCycler consensus PCR for rapid and differential detection of human erythrovirus B19 and V9 isolates
Authors: Schalasta Gunnar , Schmid Michael , Lachmund Tessa , Enders Gisela
Published: March 2004

Until recently, B19 virus was considered to be the only human pathogen of the genus erythrovirus. However, other non‐B19 virus strains, such as V9, have now been isolated and are thought to cause infections clinically and serologically indistinguishable from those caused by B19 virus. Whereas B19 virus related isolates have a low genetic diversity of only 1–2%, nucleotide disparity of up to 12% was found for the new isolates, suggesting that non‐B19 virus isolates may not be detectable using B19 virus specific PCR methods. To overcome this problem, we designed consensus primers and probes to enable the simultaneous detection of both B19 and non‐B19 virus and subsequent discrimination of the two lineages by melting temperature (Tm) analysis. A total of 196 clinical specimens, from 185 patients with a history of or an anamnesis resembling B19 virus infection, were analyzed using the consensus PCR test. Erythrovirus DNA was detected in 37 of these samples and was found to be B19 virus specific in each case, confirming previous results using B19 virus specific PCR. Although no non‐B19 virus DNA was detected in any of the clinical samples tested in this study, more extensive studies are warranted. The routine use of erythrovirus consensus PCR in the diagnosis of B19 virus infection should provide valuable information on the epidemiology and clinical role of non‐B19 virus isolates; its use in screening would increase the safety of blood products. J. Med. Virol. 73:54–59, 2004. © 2004 Wiley‐Liss, Inc.