bluuebunny/crossref_metadata_2025 huggingface dataset:
Antiangiogenic property of pigment epithelium-derived factor in hepatocellular carcinoma
Authors: Matsumoto Kojiro , Ishikawa Hiroki , Nishimura Daisuke , Hamasaki Keisuke , Nakao Kazuhiko , Eguchi Katsumi
Published: July 2004

Pigment epithelium-derived factor (PEDF) is one of the most powerful endogenous antiangiogenic reagents discovered to date. Its antiangiogenic potential in neoplastic disease remains unclear. In this study, we investigated antiangiogenic property of PEDF in hepatocellular carcinoma (HCC), a typical hypervascular tumor. In HCC cell lines, constitutive messenger RNA and protein expression of PEDF varied. Genomic DNA encoding the PEDF gene was the same in the cell lines examined by Southern blotting. In chemically induced hypoxic conditions, secreted PEDF protein was suppressed in contrast to elevation of vascular endothelial growth factor protein. When PEDF was overexpressed by gene transfer, proliferation and migration of endothelial cells were inhibited in conditioned media derived from all HCC cell lines. However, the serum concentration of PEDF, as measured by enzyme-linked immunosorbent assay, was decreased in patients with cirrhosis or HCC complicated by cirrhosis compared to healthy volunteers and patients with chronic hepatitis. According to the endothelial cell proliferation assay, the serum PEDF of patients with HCC had antiangiogenic activity. Moreover, intratumoral injection of a PEDF-expressing plasmid in athymic mouse models caused significant inhibition of preestablished tumor growth. In conclusion, PEDF plays a role in the angiogenic properties of HCC. Reduction of serum PEDF concentration associated with the development of chronic liver diseases may contribute to the progression of HCC. In addition, gene therapy using PEDF may provide an efficient treatment for HCC. (Hepatology 2004;40:252-259.)
S-adenosylmethionine and its metabolite induce apoptosis in HepG2 cells: Role of protein phosphatase 1 and Bcl-xS
Authors: Yang Heping , Sadda Mamatha R. , Li Mei , Zeng Ying , Chen Lixin , Bae Wanjun , Ou Xiaopeng , Runnegar Maria T. , Mato José M. , Lu Shelly C.
Published: July 2004

S-adenosylmethionine (SAMe) and its metabolite 5′-methylthioadenosine (MTA) are proapoptotic in HepG2 cells. In microarray studies, we found SAMe treatment induced Bcl-x expression. Bcl-x is alternatively spliced to produce two distinct mRNAs and proteins, Bcl-xL and Bcl-xS. Bcl-xL is antiapoptotic, while Bcl-xS is proapoptotic. In this study we showed that SAMe and MTA selectively induced Bcl-xS in a time- and dose-dependent manner in HepG2 cells. There are three transcription start sites in the human Bcl-x gene which yield only Bcl-xL in control HepG2 cells. SAMe and MTA treatment did not affect promoter usage, but while one promoter yielded only Bcl-xL, the other two yielded both Bcl-xL and Bcl-xS, with Bcl-xS as the predominant messenger RNA (mRNA) species. Trichostatin A, 3-deaza-adenosine, cycloleucine, and okadaic acid had no effect on Bcl-xS induction by SAMe or MTA. Calyculin A and tautomycin, on the other hand, blocked SAMe and MTA-mediated Bcl-xS induction and apoptosis in a dose-dependent manner. SAMe and MTA increased protein phosphatase 1 (PP1) catalytic subunit mRNA and protein levels and dephosphorylation of serine-arginine proteins, with the latter blocked by calyculin A. The effects of SAMe and MTA on Bcl-xS, PP1 expression, and apoptosis were also seen in 293 cells, but not in primary hepatocytes. Induction of Bcl-xS by ceramide in HepG2 cells also resulted in apoptosis. In conclusion, we have uncovered a highly novel action of SAMe and MTA, namely the ability to affect the cellular phosphorylation state and alternative splicing of genes, in this case resulting in the induction of Bcl-xS leading to apoptosis. Supplementary material for this article can be found on the Hepatology website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (Hepatology 2004;40:221-231.)
A prospective controlled study of interferon-based therapy of chronic hepatitis C in patients on methadone maintenance
Authors: Mauss Stefan , Berger Florian , Goelz Joerg , Jacob Bernhard , Schmutz Günther
Published: July 2004

We examined the feasibility of hepatitis C treatment in patients on opioid maintenance. One hundred patients with chronic hepatitis C, 50 on methadone maintenance, and 50 with no intravenous drug use or opioid maintenance for at least 5 years were prospectively matched for sex, age, hepatitis C virus (HCV) genotype and HCV RNA. The primary end point was undetectable HCV RNA at 24 weeks posttreatment. Treatment with peginterferon alfa-2b (1.5 μg/kg per week) and ribavirin (1000-1200 mg /day) was initiated for 24 weeks (HCV genotype 2, 3) or 48 weeks (HCV genotype 1, 4). Within the first 8 weeks of therapy, discontinuation due to noncompliance or patient request was observed in 22% (11/50) in the methadone group versus 4% (2/50) in the control group (P = .02). After 8 weeks, there was no significant difference in discontinuation due to noncompliance or patient request (4/39 [10%] vs. 4/48 [8%]). There was no difference in discontinuation of therapy because of viral failure or adverse events (10/50 methadone vs. 6/50 control, P = .41). At the end of treatment, 50% (25/50) in the methadone group and 76% (38/50) in the control group had undetectable HCV RNA (P = .01). Sustained viral response was 42% (21/50) in the methadone group and 56% (28/50) in the control group (P = .16). No serious psychiatric event occurred in either group. In conclusion, peginterferon and ribavirin seem reasonably safe and sufficiently effective in patients on methadone maintenance. Patients discontinuing therapy due to noncompliance or request did so early, thereby limiting the cost of an unsuccessful approach to treatment. (Hepatology 2004;40:120-124.)
Hypertonic preconditioning prevents hepatocellular injury following ischemia/reperfusion in mice: A role for interleukin 10
Authors: Oreopoulos George D. , Wu Heshui , Szaszi Kati , Fan Jie , Marshall John C. , Khadaroo Rachel G. , He Ruijan , Kapus Andras , Rotstein Ori D.
Published: July 2004

Ischemia/reperfusion (I/R) of the liver occurs in many clinical scenarios including trauma, elective surgery, and transplantation. Events initiated by this process can lead to inflammation in the liver, culminating in local injury as well as distant organ dysfunction. Recent studies have suggested that hypertonic saline exerts anti-inflammatory effects, which may be beneficial in preventing organ injury. In the present study, we examine the effect of hypertonic saline on the development of liver inflammation following I/R in both rat and mouse models. Hypertonic pretreatment was shown to prevent liver enzyme release concomitant with a reduction in liver neutrophil sequestration. Hypertonic saline appeared to exert this effect by inhibiting liver tumor necrosis factor α (TNF-α) generation, an effect that culminated in reduced liver adhesion molecule expression. Hypertonic saline pretreatment was shown to augment liver interleukin 10 (IL-10) expression following I/R, as a potential mechanism underlying its anti-inflammatory effect. To examine the role of IL-10 in the protective effect of hypertonic saline on liver I/R injury, we used a murine model of I/R. In wild type mice, hypertonic pretreatment similarly prevented liver injury induced by I/R. However, in IL-10 knockout animals, hypertonic pretreatment was unable to prevent the liver enzyme release, TNF-α generation, or neutrophil sequestration induced by I/R. In conclusion, these findings define a novel mechanism responsible for the anti-inflammatory effects of hypertonic saline and also suggest a potential clinical role for hyperosmolar solutions in the prevention of liver injury associated with I/R. Supplementary material for this article can be found on the Hepatology website (http://interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (Hepatology 2004;40:211-220.)
Free fatty acids promote hepatic lipotoxicity by stimulating TNF-α expression via a lysosomal pathway
Authors: Feldstein Ariel E. , Werneburg Nathan W. , Canbay Ali , Guicciardi Maria Eugenia , Bronk Steven F. , Rydzewski Robert , Burgart Laurence J. , Gores Gregory J.
Published: July 2004

Nonalcoholic fatty liver disease (NAFLD) is a serious health problem. Although NAFLD represents a form of lipotoxicity, its pathogenesis remains poorly understood. The aim of this study was to examine the cellular mechanisms involved in free fatty acid (FFA)-mediated hepatic lipotoxicity. FFA treatment of liver cells resulted in Bax translocation to lysosomes and lysosomal destabilization with release of cathepsin B (ctsb), a lysosomal cysteine protease, into the cytosol. This process was also partially dependent on ctsb. Lysosomal destabilization resulted in nuclear factor κB-dependent tumor necrosis factor α expression. Release of ctsb into the cytoplasm was also observed in humans with NAFLD and correlated with disease severity. In a dietary murine model of NAFLD, either genetic or pharmacological inactivation of ctsb protected against development of hepatic steatosis, liver injury, and insulin resistance with its associated “dysmetabolic syndrome.” In conclusion, these data support a lipotoxic model of FFA-mediated lysosomal destabilization. Supplemental material for this article can be found on the Hepatology website (http://www.interscience.wiley.com/jpages/0270-9139/suppmat/index.html). (Hepatology 2004;40:185-194.)
Liposome-mediated extracellular superoxide dismutase gene delivery protects against acute liver injury in mice†
Authors: Wu Jian , Liu Li , Yen Roy D. , Catana Andreea , Nantz Michael H. , Zern Mark A.
Published: July 2004

Our previous study demonstrated that polycationic liposomes are highly stable in the bloodstream and represent an effective agent for liver gene delivery. We report here that liposome-mediated extracellular superoxide dismutase (EC-SOD) gene delivery successfully prevented acute liver injury in mice. The therapeutic efficacy of EC-SOD gene delivery by polycationic liposomes was determined against the toxicity of superoxide anions and hydroxyethyl radicals in HepG2 cells and in a mouse model of acute liver injury caused by D-galactosamine and lipopolysaccharide intoxication. Transfection of HepG2 cells with an EC-SOD plasmid led to a striking increase in superoxide dismutase activity in the medium. The transfected cells had much less cell death after reactive oxygen species exposure compared with untransfected or control plasmid-transfected cells. In a model of acute liver injury, serum alanine aminotransferase levels in mice receiving portal vein injections of EC-SOD lipoplexes were much lower than in those receiving normal saline, liposomes alone, or control lipoplexes. Liver histology confirmed that there was less cell death in the EC-SOD lipoplex-treated group. Quantitative reverse transcriptase polymerase chain reaction showed a 55-fold increase in human EC-SOD gene expression in the liver of mice injected with EC-SOD lipoplexes. Serum superoxide dismutase activity in EC-SOD lipoplex-treated mice was higher than in the control groups; this was associated with higher liver glutathione levels and reduced lipid peroxidation. In conclusion, polycationic liposome-mediated EC-SOD gene delivery protects against reactive oxygen species toxicity in vitro and against lipopolysaccharide-induced acute liver injury in D-galactosamine-sensitized mice. (Hepatology 2004;40:195-204.)
Effect of biphasic calcium phosphates on drug release and biological and mechanical properties of poly(ϵ‐caprolactone) composite membranes
Authors: Kim Hae‐Won , Knowles Jonathan C. , Kim Hyoun‐Ee
Published: July 2004

Poly(ϵ‐caprolactone) (PCL) and biphasic calcium phosphate (CaP) composite membranes were prepared for use in tissue regeneration by a novel solvent casting‐pressing method. An antibiotic drug, tetracycline hydrochloride (TCH), was entrapped within the membranes to investigate the efficacy of the material as a drug delivery system. The CaP powders were varied in amount (0–50 wt %) and in powder characteristics by heat treating at different temperatures, and their effects on the mechanical and biological properties and drug release of the membranes were examined. With CaP addition up to 30 wt %, the elastic modulus of the membranes was enhanced much due to the rigidity of CaP. While the tensile strength and elongation rate decreased gradually with CaP addition because the CaP powders acted as a failure source. The osteoblast‐like cells cultured on the CaP‐PCL composite membranes exhibited significant improvements in proliferation and alkaline phosphatase (ALP) activity compared to pure PCL and culture plastic control, indicating excellent cell viability and functional activity. The TCH drugs were released from the PCL and CaP‐PCL membranes in a similar fashion; an initial burst followed by a reduced release rate. The initial burst effect diminished much by the addition of CaP powders. The CaP addition increased the drug release rate after an initial period, and this was attributed to the high water uptake capacity and dissolution of the CaP containing membranes. Compared to the composite membranes containing heat‐treated CaP powders, those with as‐precipitated ones had higher dissolution and drug releases. These observations on mechanical properties and cellular responses as well as on drug release profiles suggested that the CaP‐PCL composite membranes are potentially applicable to tissue regeneration and drug delivery system. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 467–479, 2004
p‐Aminophenol‐induced hepatotoxicity in hamsters: Role of glutathione
Authors: Fu Xin , Chen Theresa S. , Ray Mukunda B. , Nagasawa Herbert T. , Williams Walter M.
Published: July 2004

p‐Aminophenol (PAP) is a widely used industrial chemical and a known nephrotoxin. Recently, it was found to also cause hepatotoxicity and glutathione (GSH) depletion in mice. The exact mechanism of liver toxicity is not known. The aims of this study were to determine whether PAP can cause acute hepatotoxicity in hamsters and to further investigate the role of GSH in PAP‐induced toxicity. PAP was administered ip to hamsters in doses of 200–800 mg/kg. Liver damage at 24 h after PAP administration was assessed by elevations in plasma enzyme activities and histopathologic examination. GSH and cysteine (Cys) levels in liver at 4 h were determined by HPLC. PAP decreased hepatic GSH concentration to 8% and Cys to 30% of vehicle control values. It increased plasma glutamic pyruvic transaminase (GPT) activity by 47‐fold and sorbitol dehydrogenase (SDH) activity by 113‐fold. PAP also caused severe centrilobular hepatocellular necrosis. 2(RS)‐n‐Propylthiazolidine‐4(R)‐carboxylic acid (PTCA), a Cys precursor, attenuated the PAP‐induced decreases in hepatic sulfhydryl levels; GSH and Cys were 39% and 78% of vehicle controls, respectively. PTCA also attenuated the PAP‐induced elevations in plasma enzyme activities and hepatic necrosis. It was concluded that PAP hepatotoxicity is associated with depletion of hepatic GSH and can be prevented by PTCA. © 2004 Wiley Periodicals, Inc. 18:154–161, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/jbt.20021
Structural characterization of corrosion products on archaeological iron: an integrated analytical approach to establish corrosion forms
Authors: Neff Delphine , Reguer Solenn , Bellot‐Gurlet Ludovic , Dillmann Philippe , Bertholon Régis
Published: July 2004

The description and identification of corrosion products formed on archaeological iron artefacts need various approaches at different observation scales. For this study, samples from five sites were prepared using two techniques. The first consists in cutting cross‐sections perpendicular to corrosion layers. This allows local observations and analysis of the corrosion layer stratigraphy at different levels. The second consists in performing manual grinding or abrading of the corrosion layers starting from the current surface of the excavated artefact to the metal core. It allows the description of the successive layers and is well adapted for the analysis on a larger scale. In addition to these two observation scales, the identification of the iron oxides formed needs the coupling of several complementary techniques. Elementary compositions were determined by scanning electron microscopy–energy‐dispersive x‐ray (SEM–EDX) analysis and electron probe microanalysis (EPMA). Structural identification was performed by x‐ray micro‐diffraction under synchrotron radiation (µXRD) and micro‐Raman spectroscopy. These analyses were performed on the same samples with both x‐ray diffraction and Raman spectroscopy in order to ensure a reliable characterization. In some cases there are some ambiguities or overlapping between signatures of different phases by µXRD (such as maghaemite–magnetite) or Raman spectroscopy (such as goethite–magnetite) which can be overcome by the association of the two methods. The final aim is to set up an analytical methodology that will be optimal for the study of ancient iron corrosion products. It is the first step in the study of long‐term mechanisms of iron in soil. Copyright © 2004 John Wiley & Sons, Ltd.
Raspite and studtite: Raman spectra of two unique minerals
Authors: Bastians Simon , Crump Gregory , Griffith William P. , Withnall Robert
Published: July 2004

The Raman and IR spectra of monoclinic naturally occurring raspite, α‐PbWO4 (space group P21/a) were measured; it is irreversibly transformed to the tetragonal stolzite, β‐PbWO4, by heating to 450°C, and this process was followed by Raman spectroscopy. Assignments of fundamental modes are proposed. New data are also presented on single crystals of stolzite (space group I41/a), and it is shown that raspite and stolzite can easily be distinguished by their Raman spectra. We also present Raman and IR spectroscopic data on natural and synthetic studtite, UO4·4H2O, and its synthetic dehydration product metastudtite, UO4·2H2O, the only two naturally occurring peroxide‐containing minerals, and on partially deuterated synthetic forms of these materials. Assignments of fundamental modes are proposed and both TGA and DSC data are presented for studtite. Copyright © 2004 John Wiley & Sons, Ltd.
Raman spectroscopy and UV pulsed laser: an excellent symbiosis?
Authors: Ruiz‐Moreno Sergio , López‐Gil Alejandro , Gabaldón Amador , Sandalinas Carmen
Published: July 2004

The fundamental idea of the present work concerns photon technology performance. On the one hand, in order to improve the Raman spectral quality when pigment analysis is carried out, we use UV pulsed laser radiation (266 nm) and its non‐thermal photoablation‐induced effect. In this way, the unwanted superficial layers (old varnishes, for example, in easel paintings) can be locally removed and so a reduction of the total fluorescence in the spectrum of the analyzed zone is achieved. On the other hand, for the purpose of analyzing the quality of the process, we employ Raman spectroscopy to obtain molecular information about the previous and later compositions of the surface irradiated with UV pulses. The fluorescence reduction of the Raman spectra and its consequent spectral quality improvement are quantified by a proposed figure of merit (signal‐to‐noise ratio) which is calculated in a suitable spectral range. The UV pulses are obtained starting an Nd:YAG pulsed laser (1064 nm) in combination with non‐linear optical crystals, and the Raman system used in the analytical measurements is a Jobin Yvon Induram with optical fiber technology and an HeNe continuous laser (632.8 nm). A Haas shutter guarantees the spatial focusing of the optical pulses over a concrete point of the irradiated sample. Based on the experimental results, two conclusions can be established: first, non‐thermal photoablation is very effective at removing small areas of the superficial varnished layers; second, Raman spectroscopy and the proposed figure of merit are very useful for measuring the resulting improvement in spectral quality. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of nineteenth century blue and green pigments by in situ x‐ray fluorescence and micro‐Raman spectroscopy
Authors: Rosi F. , Miliani C. , Borgia I. , Brunetti B. , Sgamellotti A.
Published: July 2004

A mural painting by the innovative Italian miniaturist Napoleone Verga (1833–1918) was studied by a model protocol that combines an in situ non‐destructive technique with laboratory micro‐destructive vibrational investigations. The experimental procedure allowed us to acquire detailed information not only on Verga's palette and painting technique but also on undocumented retouches, using a very restricted number of samples. Copyright © 2004 John Wiley & Sons, Ltd.
Raman micro‐spectroscopy of western Mediterranean obsidian glass: one step towards provenance studies?
Authors: Bellot‐Gurlet Ludovic , Bourdonnec François‐Xavier Le , Poupeau Gérard , Dubernet Stephan
Published: July 2004

This paper presents the first results of the Raman characterization of obsidians from the western Mediterranean. About 40 geological samples, from the islands of Lipari, Palmarola, Pantelleria and Sardinia, representative of the seven archaeologically significant obsidian sources, were analysed. Apart from the general shape of the spectra, which characterize three islands, a detailed treatment of the stretching massif part was performed to obtain quantitative discriminating parameters. The combination of these factors seems to provide a complete discrimination of all archaeologically significant western Mediterranean sources. These sources have provided raw material of Meso‐ and Neolithic artefacts distributed around the Tyrrhenian basin and nowadays provide key evidence of ancient exchange networks. Because some alternatives to classical geochemical fingerprinting are currently being sought, Raman spectroscopy could be a complementary or even alternative technique in provenance studies of archaeological obsidians. Copyright © 2004 John Wiley & Sons, Ltd.
The use of micro‐Raman spectroscopy in architectural paint analysis
Authors: Kendix E. , Nielsen O. F. , Christensen M. C.
Published: July 2004

Architectural paint analysis is an important technique for establishing the palette of historical paint colours, and reconstructing how a room or a facade might have looked at an earlier time. In its simplest form, it has often been achieved by using paint scrapes, which involves revealing a stepped sequence of layers of paint using a blade or solvents. Cross‐sections are used as an alternative to, or in combination with, scrapes. Mounted cross‐sections can be examined by optical microscopy. Accumulated layers of paint, wallpaper or other applied decorative finishes can be defined from their textures and colours. Knowledge of the identity of the components in paint layers can be used to reconstruct a certain paint and also to date the paint layers. It is demonstrated that micro‐Raman spectroscopy combined with optical microscopy and low‐vacuum scanning electron microscopy–energy‐dispersive spectrometry are versatile tools for the characterization of pigments and fillers in cross‐sections from architectural decorations. The paper gives an example of the examination of an interior decoration from a historical building. Copyright © 2004 John Wiley & Sons, Ltd.
Bronze Age painted plaster in Mycenaean Greece: a pilot study on the testing and application of micro‐Raman spectroscopy
Authors: Brysbaert Ann , Vandenabeele Peter
Published: July 2004

Since the first discoveries of Minoan and Mycenaean painted plaster around the end of the 19th and early 20th centuries, iconographic and, to a lesser extent, technological studies have gone hand in hand in order to understand how these prehistoric societies were able to produce some of the earliest and most significant works of art in Bronze Age Europe and the eastern Mediterranean. These paintings claim to be among the first to be executed in the buon fresco technique. Past technological studies employed wet chemical methods, x‐ray diffraction (XRD), optical emission spectroscopy and a range of microscopic techniques based on cross‐sections of samples in order to investigate these fragmentary paintings. Most of these methods required destructive sampling and this is now, rightly so, very much restricted. Consequently, other non‐micro‐destructive approaches are being tested at present. Micro‐Raman spectroscopy (MRS) has proven more than once its potential for non‐destructive analysis of works of art and in archaeology in the recent past. Its application to this early fragmentary material is presented here for the first time. Interesting results were the identification of both organic (indigo) and non‐crystalline materials (limonite), which complements the knowledge obtained from traditionally used techniques. Although not without problems (high fluorescence prevented identification of Egyptian Blue), non‐destructive MRS yielded results comparable to XRD and provided the first identification of indigo blue on this medium, and can hence be considered very useful in future sample‐reducing strategies considering these scarce materials. Copyright © 2004 John Wiley & Sons, Ltd.
Raman investigation of ceramics from 16th and 17th century Portuguese shipwrecks
Authors: de Waal Danita
Published: July 2004

Raman spectra were recorded of the various components of a series of about 20 ceramic shards from nine Portuguese ships that were wrecked around the South African coast between 1550 and 1650. α‐Quartz was a typical component of the porcelain body. The blue pigment could be identified as CoAl2O4, or cobalt blue, and the glaze covering the ceramic surface presented a series of broad Raman bands typical of amorphous silicates. One shard from the Santa Maria Madre de Deus, which looked different form the other shards, was shown not to be a porcelain owing to the various components (CaCO3, CaSO4 · 2H2O or gypsum, amorphous carbon, anatase) which could be identified in the ceramic. This is an indication that this one piece is unlikely to be of the same Chinese origin as the Ming porcelain shards. Copyright © 2004 John Wiley & Sons, Ltd.
Comparison between analytical methods and biological assays for the assessment of tannin‐related antinutritive effects in some Spanish browse species
Authors: Ammar Hajer , López Secundino , González Jesús S , Ranilla María J
Published: July 2004

Twenty‐two samples of leaves and flowers of six Mediterranean browse species (Erica australis, Quercus pyrenaica, Cistus laurifolius, Cytisus scoparius, Genista florida and Rosa canina) were analysed for total extractable phenols (TP), extractable tannins (ET) and condensed tannins (CTb (butanol/HCl assay) and CTv (vanillin assay)). The biological activity of the phenolic compounds was assessed as the increases in in vitro dry matter digestibility and gas production after in vitro incubation in rumen fluid following the addition of polyethylene glycol 6000 (PEG). The concentrations of phenolics and tannins varied with species, sampling time and part of the plant (leaves or flowers). There were also large differences in the values determined by different analytical methods. The highest correlation coefficients (P < 0.001) were found between TP and ET (r = 0.973) and between CTb and CTv (r = 0.758). However, only low correlations were observed between TP and CTb or CTv. Positive and significant (P < 0.01) correlations were observed between tannins and their biological activity determined as the effect of PEG on gas production. It is concluded that, although further research is required to develop methods for the accurate quantification of biologically active tannins, the effect of PEG on in vitro gas production seems to have promising potential for the assessment of phenolic‐related antinutritive effects in browse plants. This technique, coupled with other tannin assays, could provide a better understanding of the nutritional and physiological significance of tannins. Copyright © 2004 Society of Chemical Industry
Evaluation and optimisation of five different extraction methods for soy DNA in chocolate and biscuits. Extraction of DNA as a first step in GMO analysis
Authors: Gryson Nicolas , Messens Kathy , Dewettinck Koen
Published: July 2004

A method is described to discriminate between genetically modified (GM) and non‐modified foodstuffs by detecting the presence of newly introduced genes at the protein or DNA level. Currently available methods operate almost exclusively at the DNA level and are based on the polymerase chain reaction (PCR). The first and most crucial step in this process is the isolation of DNA. In this study, five different methods for the isolation of DNA from chocolate and biscuits were evaluated, using four commercially available extraction kits and a non‐commercial method for amplification of the soybean‐specific lectin gene. The latter method involves the use of hot‐start Taq polymerase, to prevent the formation of non‐specific amplification products, and an increase in the number of cycles from 35 to 41. The performance of the non‐commercial cetyl trimethylammonium bromide (CTAB)‐based method was the best, taking into consideration the adaptations of the extraction procedure, although this method was more time‐consuming than the others. Chocolate (white, milk and dark) and several biscuits generated positive amplification results using this PCR approach. Copyright © 2004 Society of Chemical Industry
Influence of lipase and/or emulsifier addition on the ileal and faecal nutrient digestibility in growing pigs fed diets containing 4% animal fat
Authors: Dierick NA , Decuypere JA
Published: July 2004

Information on the addition of lipase and/or emulsifiers to less digestible or saturated fat sources, such as tallow or other animal fats, used in swine feeding is very limited. Therefore, in a 4 × 4 Latin square design, the effects of adding lipase (0.05% L5, microbial source) and/or an emulsifier (0.3% Lysoforte) on the apparent ileal (AID) and faecal (AFD) digestibility of the main nutrients and fatty acids in particular were studied with four ileal‐cannulated growing pigs (female, initial live weight 20 kg) fed diets containing barley/soybean meal supplemented with 4% animal fat. The fat source contained 35% saturated (S) and 65% unsaturated (U) fatty acids. All diets were free of antibacterial substances (antibiotics, copper sulphate or zinc oxide beyond requirements), in order to avoid interactions between the parameters studied and the gut flora. Lipase addition did not affect the AID or AFD of fat. However, the digestibility of minor fatty acids (C6:0, C14:0) was significantly improved by lipase at both ileal and faecal level. On the other hand, lipase supplementation (P < 0.05) improved the AID of dry matter (DM) and energy as well as the AFD of DM, organic matter (OM), crude protein (CP), ash and energy. Addition of an emulsifier did not have any significant influence on the AID or AFD of fat, while the AID values of DM, OM, CP and energy as well as the AFD values of DM, OM, CP and ash were significantly (P < 0.05) improved. Adding lipase in combination with an emulsifier to the diets decreased (P < 0.05) the AID and AFD of fat, with minor effects on the AID and AFD of the non‐fat components of the diet. The lack of improvement in the digestion of fat by exogenous lipase and/or emulsifier may be related to the rather high U/S ratio (0.65:0.35) of the animal fat source used and to the mode of incorporation of the emulsifier (no pre‐dispersion in the fat source). Furthermore, during the trial the diets, stored at room temperature, showed a steady increase in their content of free fatty acids (to more than 700 g kg−1 fat), due to endogenous lipase activity, leaving less room for upgrading the digestion of animal fat by exogenous lipase and/or emulsifier. Copyright © 2004 Society of Chemical Industry
Elevated carbon dioxide affects fruit flavor in field‐grown strawberries (Fragaria×ananassaDuch)
Authors: Wang SY , Bunce JA
Published: July 2004

The effect of elevated carbon dioxide on fruit quality and aroma volatile composition in field‐grown strawberries (Fragaria×ananassaDuch) was studied. Elevating the ambient CO2concentration (ambient + 300, and ambient +600 µmol mol−1CO2) resulted in high fruit dry matter, fructose, glucose and total sugar contents and low citric and malic acid contents. High CO2growing conditions significantly enhanced the fruit content of ethyl hexanoate, ethyl butanoate, methyl hexanoate, methyl butanonate, hexyl acetate, hexyl hexanoate, furaneol, linalool and methyl octanoate. Thus, the total amounts of these compounds were higher in berries grown in CO2‐enriched conditions than those grown in ambient conditions. The highest CO2enrichment (600 µmol mol−1) condition yielded fruit with the highest levels of these aroma compounds. Copyright © 2004 Society of Chemical Industry
Gilthead seabream (Sparus aurata): suitability for freezing and commercial alternatives
Authors: Huidobro Almudena , Tejada Margarita
Published: July 2004

The quality of portion‐size farmed gilthead seabream (Sparus aurata) during frozen storage and the influence of post‐mortem treatments were studied in order to find new ways of marketing this species. Portion‐sized gilthead seabream, fasted for 48 h prior to slaughter, were frozen and stored at −20 °C for up to one year. Whole fish were frozen immediately after rigor mortis; gutted fish were frozen immediately after rigor and after 5 days of storage in ice. All lots were stored at −20 °C for up to one year. The myofibrillar protein of this species was very stable and a slight decrease of solubility in salt solutions was found only after one year of frozen storage. A slight decrease in water‐holding capacity and a slight increase in shear strength were observed, but these were lower than in other species. These changes were reflected as increased toughness and reduced juiciness in sensory analysis of the cooked fillets after one year. The main changes in the cooked fillets were observed in odour and flavour. No significant detrimental effect due to the guts was detected during frozen storage. Storage in ice prior to freezing was reflected in sensory assessment of the raw fish, mainly in terms of initial higher demerit points for fishy odour, gills and eyes; however, no effect was observed in the cooked fillets. Copyright © 2004 Society of Chemical Industry
Effects of endogenous flour lipids on the quality of short‐dough biscuits
Authors: Papantoniou Eleni , Hammond Eugene W , Scriven Fiona , Gordon Michael H , Schofield J David
Published: July 2004

Fractionation and reconstitution techniques were used to study the contribution of endogenous flour lipids to the quality of short‐dough (shortcake type) biscuits. Biscuit flour was defatted with chloroform and baked with bakery fat, but without endogenous lipid. Short‐dough biscuits baked from defatted flour had smaller diameters, and were flatter, denser and harder than control biscuits. Defatted flour shortcake doughs exhibited different rheological behaviour from the control samples, showing higher storage and loss moduli (G′ and G″ values), ie higher viscoelasticity. Functionality was restored when total non‐starch flour lipids were added back to defatted flour. The polar lipid fraction had a positive effect in restoring flour quality whereas the non‐polar lipid fraction had no effect. Both fractions were needed for complete restoration of both biscuit quality and dough rheological characteristics. A study of the microstructure of defatted biscuits revealed that their gluten protein was more hydrated and developed than the gluten of the control biscuits. This conclusion was supported by the higher water absorption of the defatted gluten. Copyright © 2004 Society of Chemical Industry
Application of different forms of calcium to tea soil to prevent aluminium and fluorine accumulation
Authors: Fung KF , Wong MH
Published: July 2004

Tea Camellia sinensis (L), is a well‐known accumulator of aluminium and fluorine from acidic soil. A reduction is desirable as aluminium and fluorine absorbed will leach into the tea liquor through infusion, thus posing a serious threat to the health of consumers. The present study aims to investigate the effects of adding different forms of calcium on Al and F uptake by tea plants, in order to reduce the concentrations of these elements contained in the plants. All true lime materials increased the soil pH and decreased soil extractable Al and F concentrations. There were no (p < 0.05) changes in pH values when CaCl2 was added, and a slight decrease in Al and F concentrations was observed in the treatments with CaSO4. Tea seedlings under the addition of CaSO4 were the tallest and healthiest, followed by CaCl2, CaCO3, Ca(OH)2 and CaO. Seedlings under large doses of Ca(OH)2 and CaO were dead. Relative growth rates decreased significantly with the increase of calcium compounds except in CaSO4 treatment. The highest Al concentration was also found in the treatment of 4000 mg CaSO4 kg−1; it then decreased gradually from 3364 to 933 mg Al kg−1 in leaves. For all treatments in both varieties, F concentrations in leaves were lower than the control (374 mg kg−1). Calcium chloride was a suitable agent for reduction of Al and F uptake by tea plants while maintaining a high growth rate of the seedlings. Copyright © 2004 Society of Chemical Industry
The Ring Opening Metathesis Polymerisation Toolbox
Authors: Slugovc Christian
Published: July 2004

Summary: The success of metathesis chemistry techniques has sparked a tremendous interest in polymer and material chemistry. This contribution provides an overview of the state of the art in ring opening metathesis polymerisation (ROMP). It is intended to provide the reader with useful information on the interplay of initiators, monomers, and reaction conditions, thus aiding polymer chemists to utilise the ROMP toolbox. Prominent and illustrative examples from current research are given in the article.

The “ROMP toolbox”.

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The “ROMP toolbox”.
Unusual Crystallization Behavior in Nylon‐6 and Nylon‐6/Montmorillonite Nanocomposite Films
Authors: Zhao Zhudi , Zheng Weitao , Yu Wenxue , Tian Hongwei , Li Hujie
Published: July 2004

Summary: The crystallization behavior of nylon‐6 and nylon‐6/montmorillonite nanocomposite films with different heat histories was investigated by wide‐angle X‐ray diffraction (WAXD). For nylon‐6 films isothermally crystallized above 170 °C or annealed at 200 °C and then quenched in ice water, a crystalline peak appeared at 2θ = 28.5°. This crystalline peak was strong in intensity for the former and weak for the latter. However, for nylon‐6 films cooled in air after isothermal crystallization or annealing, no crystalline peak at 2θ = 28.5° was observed in the WAXD patterns. For nylon‐6/montmorillonite nanocomposite films annealed above 140 °C, a crystalline double peak was observed between the α1 and α2 peaks. The possible origins of the peak at 2θ = 28.5° and the crystalline double peak are discussed.

WAXD patterns of isothermally crystallized nylon‐6/montmorillonite nanocomposite films.

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WAXD patterns of isothermally crystallized nylon‐6/montmorillonite nanocomposite films.
Pruning of motor neuron branches establishes the DLM innervation pattern in Drosophila
Authors: Hebbar Sarita , Fernandes Joyce J.
Published: July 2004

During the Drosophila life‐cycle two sets of neuromuscular junctions are generated: the embryonic/larval NMJs develop during the first half, followed by the period of metamorphosis during which the adult counterpart is generated. Development of the adult innervation pattern is preceded by a withdrawal of larval NMJs, which occurs at the onset of metamorphosis, and is followed by adult‐specific motor neuron outgrowth to innervate the newly developing adult fibers. Establishment of the adult innervation pattern occurs in the context of a broader restructuring of the nervous system, which results in the development of neural circuits that are necessary to carry out behaviors specific to the adult. In this article, we follow development of the dorsal longitudinal muscle (DLM) innervation pattern through metamorphosis. We find that the initial period of motor neuron elaboration is followed by a phase of extensive pruning resulting in a threefold reduction of neuromuscular contacts. This event establishes the adult pattern of second order branching. Subsequent higher order branching from the second order “contact” points generates the characteristic multiterminal innervation pattern of the DLMs. Boutons begin to appear after the pruning phase, and are much smaller than their larval counterparts. Additionally, we demonstrate that the DLM innervation is altered in the hyperexcitable double mutant, ether a go‐go Shaker, and that the phenotype is suppressed by the hypoexcitable mutant, napts1. Our results demonstrate that electrical activity regulates the patterning of DLM innervation during metamorphosis. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 499–516, 2004
In vivo analysis reveals different apoptotic pathways in pre‐ and postmigratory cerebellar granule cells of rabbit
Authors: Lossi Laura , Gambino Graziana , Mioletti Silvia , Merighi Adalberto
Published: July 2004

Naturally occurring neuronal death (NOND) has been described in the postnatal cerebellum of several species, mainly affecting the cerebellar granule cells (CGCs) by an apoptotic mechanism. However, little is known about the cellular pathway(s) of CGC apoptosis in vivo. By immunocytochemistry, in situ detection of fragmented DNA, electron microscopy, and Western blotting, we demonstrate here the existence of two different molecular mechanisms of apoptosis in the rabbit postnatal cerebellum. These two mechanisms affect CGCs at different stages of their maturation and migration. In the external granular layer, premigratory CGCs undergo apoptosis upon phosphorylation of checkpoint kinase 1 (Chk1), and hyperphosphorylation of retinoblastoma protein. In postmigratory CGCs within the internal granular layer, caspase 3 and to a lesser extent 7 and 9 are activated, eventually leading to poly‐ADP‐ribose polymerase‐1 (PARP‐1) cleavage and programmed cell death. We conclude that NOND of premigratory CGCs is linked to activation of DNA checkpoint and alteration of normal cell cycle, whereas in postmigratory CGCs apoptosis is, more classically, dependent upon caspase 3 activation. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 437–452, 2004
Background sodium current stabilizes bursting in respiratory pacemaker neurons
Authors: Tryba Andrew K. , Ramirez Jan‐Marino
Published: July 2004

Endogenous pacemaker properties have been proposed to generate rhythmic activity underlying many behaviors including respiration. For pacemakers to generate regenerative bursting, background currents maintain their membrane potential (Vm) within a range where bi‐stable properties are expressed, thereby stabilizing rhythmogenesis. We previously found that the baseline Vm of respiratory pacemakers is stabilized against hyperpolarizing shifts in their Vm. In response to prolonged hyperpolarizing current injection synaptically isolated respiratory pacemakers steadily depolarize and resume bursting, suggesting a stabilizing background current is involved. What is the ionic basis of this background current in respiratory pacemakers? Here we demonstrate that in low‐[Na+]o ACSF, synaptically isolated respiratory pacemakers hyperpolarized and remained outside the bursting window, but could burst upon depolarizing current injection. These data suggest that pacemakers possess a background sodium current that is necessary to bring their Vm into a bursting range. Low‐[Na+]o ACSF also abolished the depolarizing shift evoked during prolonged hyperpolarizing current injection, and bursting did not resume. This depolarizing shift persisted in the presence of Ih‐current blockers, but was abolished in tetrodotoxin. Although, under control conditions, the Vm of synaptically isolated respiratory pacemaker neurons was not significantly affected when [K+]o was changed from 3 to 8 mM, the Vm is altered when [K+]o was raised in low‐[Na+]o ACSF. Thus, current‐clamp studies suggest that respiratory pacemaker neurons possess a background sodium current that maintains their membrane potential within a range where they express bursting, thereby stabilizing rhythmogenesis. © 2004 Wiley Periodicals, Inc. J Neurobiol 60: 481–489, 2004
A spectral‐element method for modelling cavitation in transient fluid–structure interaction
Authors: Sprague M. A. , Geers T. L.
Published: July 2004

In an underwater‐shock environment, cavitation (boiling) occurs as a result of reflection of the shock wave from the free surface and/or wetted structure causing the pressure in the water to fall below its vapour pressure. If the explosion is sufficiently distant from the structure, the motion of the fluid surrounding the structure may be assumed small, which allows linearization of the governing fluid equations. In 1984, Felippa and DeRuntz developed the cavitating acoustic finite‐element (CAFE) method for modelling this phenomenon. While their approach is robust, it is too expensive for realistic 3D simulations. In the work reported here, the efficiency and flexibility of the CAFE approach has been substantially improved by: (i) separating the total field into equilibrium, incident, and scattered components, (ii) replacing the bilinear CAFE basis functions with high‐order Legendre‐polynomial basis functions, which produces a cavitating acoustic spectral element (CASE) formulation, (iii) employing a simple, non‐conformal coupling method for the structure and fluid finite‐element models, and (iv) introducing structure–fluid time‐step subcycling. Field separation provides flexibility, as it admits non‐acoustic incident fields that propagate without numerical dispersion. The use of CASE affords a significant reduction in the number of fluid degrees of freedom required to reach a given level of accuracy. The combined use of subcycling and non‐conformal coupling affords order‐of‐magnitude savings in computational effort. These benefits are illustrated with 1D and 3D canonical underwatershock problems. Copyright © 2004 John Wiley & Sons, Ltd.
Local modal reduction in explicit dynamics with domain decomposition. Part 1: extension to subdomains undergoing finite rigid rotations
Authors: Faucher Vincent , Combescure Alain
Published: July 2004

We present an extension of the dual Schur multidomain method with local linear modal reduction previously introduced by Gravouil, Combescure, Herry and Faucher to the case of modal reduction on geometrically non‐linear vibrating subdomains. This first part of a two‐part paper describes a new formalism, based on an original set of parameters, to represent a subdomain's finite rigid‐body motion. Special attention is paid to the stability issues with time integration using the central difference scheme. The method is validated on an academic example and its efficiency is demonstrated on a large‐scale example. Copyright © 2004 John Wiley & Sons, Ltd.