bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Cloning and Characterization of a cDNA Encoding a Transferrin Homolog from Bombyx mori
Authors: Yun Eun Young , Kang Seok Woo , Hwang Jae Sam , Goo Tae Won , Kim Sang Hyun , Jin Byung Rae , Kwon O-Yu , Kim Keun Young
Published: October 2004

We isolated a cDNA representing a message that was strongly induced by injection withE. coliinBombyx mori. The 2160 bp cDNA has an open reading frame of 644 amino acids and the deduced product a predicted molecular mass of 71 kDa. The cDNA sequence shared high homology with the transferrins known so far, and its deduced peptide had unique features of transferrins, that is, sites of cystein residues and iron binding. We suggest that theB. moritransferrin plays an important role in the self-defense system.
Osteopontin Modulates Prostate Carcinoma Invasive Capacity through RGD-Dependent Upregulation of Plasminogen Activators
Authors: Angelucci Adriano , Festuccia Claudio , DAndrea Gabriele , Teti Anna , Bologna Mauro
Published: October 2004

Osteopontin, a noncollageneous bone matrix protein,
is produced in several human tumors but its role
in cancer progression has been only partially elucidated.
In this study we investigated the potential role
of osteopontin in the malignancy of prostate cancer
cells. Chemotaxis and chemoinvasion analyses revealed
a dosedependent increase in PC3 cell movement
induced by osteopontin and a strict dependence
of cell invasion on αvβ3 integrin function. The
pattern of protease expression was modified by osteopontin
and was characterized by an upregulation
of plasminogen activators. Our findings suggest that
osteopontin may confer selective malignant potential
to prostate cancer cells through the enhancement of
their invasive and proteolytic capability.
TCF: Lady Justice Casting the Final Verdict on the Outcome of Wnt Signalling
Authors: Brantjes H. , Barker N. , Es J. van , Clevers H.
Published: October 2004

The Wnt signalling cascade plays an important role during embryonic patterning and cell fate determination and is highly conserved throughout evolution. Factors of the TCF/LEF HMG domain family (Tcfs) are the downstream effectors of this signal transduction pathway. Upon Wnt signalling, a cascade is initiated that results in the translocation of βcatenin to the nucleus, where it interacts with Tcf to generate a transcriptionally active complex. This bipartite transcription factor is targeted to the upstream regulatory regions of Tcf target genes. In the absence of Wnt signals, βcatenin is degraded in the cytoplasm via the ubiquitinproteasome pathway. Several proteins are instrumental in achieving this tight regulation of βcatenin levels in the cell, including adenomatous polyposis coli (APC), GSK3 β, and Axin/Conductin. Deregulation of the Wnt signalling pathway is implicated in several forms of cancer, such as colon carcinoma and melanoma. This deregulation is achieved via mutation of APC, βcatenin or Axin, resulting in elevated βcatenin levels and the presence of constitutively active Tcfβcatenin complexes in the nucleus. The accompanying inappropriate activation of target genes is considered to be a critical, early event in this carcinogenesis. In addition to regulating βcatenin levels, normal healthy cells have evolved a second level of regulation, by manipulating the activity of the Tcf proteins themselves. In the absence of Wnt signalling, Tcf complexes with several transcriptional repressor proteins ensuring active repression of Tcf target genes. In this review the dual role of Tcf proteins in the Wnt signalling cascade will be discussed.
Functional Analysis of the Escherichia coli Molybdopterin Cofactor Biosynthesis Protein MoeA by Site-Directed Mutagenesis
Authors: Sandu C. , Brandsch R.
Published: October 2004

Five moeA mutants were generated by replacing some conserved amino acids of MoeA by sitedirected mutagenesis. The mutants were assayed for the ability to restore in vivo nitrate reductase activity of the moeA mutant Escherichia coli JRG97 and in vitro Neurospora crassa nit-1 nitrate reductase activity. The replacements Asp59AlaGly60Ala, Asp259Ala, Pro298AlaPro301Ala abolished the function of MoeA in Momolybdopterin formation and stabilization, reflected in the inability to restore nitrate reductase activity. The replacements Gly251AlaGly252Ala reduced, and that of Pro283Ala had no effect, on nitrate reductase activity. E. coli JRG97 cells transformed with mutants that failed to restore nitrate reductase activity showed by HPLC analysis a decreased level of molybdopterinderived dephospho FormA as compared to bacteria transformed with wildtype moeA. The effects of the amino acid replacements on MoeA function may be explained in correlation with the MoeA crystal structure.
(6R)-5,6,7,8-Tetrahydro-L-Monapterin from Escherichia coli, a Novel Natural Unconjugated Tetrahydropterin
Authors: Ikemoto K. , Sugimoto T. , Murata S. , Tazawa M. , Nomura T. , Ichinose H. , Nagatsu T.
Published: October 2004

The structure of the major tetrahydropterin in Escherichia coli was determined as (6R)-5,6,7,8-tetrahydroLmonapterin, i. e. (6R)-2-amino-5,6,7,8-tetrahydro 6-[(1S,2S)-1,2,3-trihydroxypropyl]pteridin-4(3H)one. Although the stereochemical structure of the trihydroxypropyl side chain has been determined previously by fluorescence detected circular dichroism analysis on its aromatic derivative, the most important configuration at C(6) has not been clarified. The major difficulties for the determination of the chirality were instability toward air oxidation and very low concentration of the tetrahydropterin derivative. In the present study, the C(6)configuration was determined as R by comparing its stable hexaacetyl derivative with authentic (6R) and (6S)hexaacetyl-5,6,7,8- tetrahydroLmonapterins by high performance liquid chromatography (HPLC) and HPLCmass spectrometry (LCMS). (6R)-5,6,7,8-TetrahydroLmonapterin is a new unconjugated tetrahydropterin from natural sources.
Non-Antioxidant Properties of Carotenoids
Authors: Stahl W. , Ale-Agha N. , Polidori M.C.
Published: October 2004

Dietary antioxidants such as carotenoids, tocopherols, vitamin C or flavonoids exhibit biological activities that are not directly related to their antioxidant properties. The parent compounds and/or their metabolites have impact on cellular signaling pathways, influence the expression of certain genes or act as inhibitors of regulatory enzymes. Thus, they reveal additional biological effects which might be of importance in context with the prevention of degenerative diseases related to the consumption of a diet rich in antioxidants. This review focuses on known nonantioxidant properties of carotenoids, including retinoiddependent signaling, stimulation of gap junctional communications, impact on the regulation of cell growth and induction of detoxifying enzymes, such as cytochrome P450-dependent monooxygenases.
The Specificity of Lipoxygenase-Catalyzed Lipid Peroxidation and the Effects of Radical- Scavenging Antioxidants
Authors: Noguchi N. , Yamashita H. , Hamahara J. , Nakamura A. , Kühn H. , Niki E.
Published: October 2004

The oxidation of low density lipoprotein (LDL) by lipoxygenase has been implicated in the pathogenesis of atherosclerosis. It has been known that lipoxygenasemediated lipid peroxidation proceeds in general via regio, stereo and enantiospecific mechanisms, but that it is sometimes accompanied by a share of random hydroperoxides as side reaction products. In this study we investigated the oxidation of various substrates (linoleic acid, methyl linoleate, phosphatidylcholine, isolated LDL, and human plasma) by the arachidonate 15-lipoxygenases from rabbit reticulocytes and soybeans aiming at elucidating the effects of substrate, lipoxygenase and reaction milieu on the contribution and mechanism of random oxidation and also the effect of antioxidant. The specific character of the rabbit 15-lipoxygenase reaction was confirmed under all conditions employed here. However, the specificity by soybean lipoxygenase was markedly dependent on the conditions. When phosphatidylcholine liposomes and LDL were oxygenated by soybean lipoxygenase, the product pattern was found to be exclusively regio, stereo, and enantiorandom. When free linoleic acid was incorporated into PC liposomes and oxidized by soybean lipoxygenase, the free acid was specifically oxygenated, whereas esterified linoleate gave random oxidation products exclusively. Radicalscavenging antioxidants such as αtocopherol, ascorbic acid and 2-carboxy-2,5,7,8-tetramethyl-6-chromanol selectively inhibited the random oxidation but did not influence specific product formation. It is assumed that the random reaction products originate from free radical intermediates, which have escaped the active site of the enzyme and thus may be accessible to radical scavengers. These data indicate that the specificity of lipoxygenasecatalyzed lipid oxidation and the inhibitory effects of antioxidants depend on the physicochemical state of the substrate and type of lipoxygenase and that they may change completely depending on the conditions.
Calpain Function in the Differentiation of Mesenchymal Stem Cells
Authors: Yajima Yukiko , Kawashima Seiichi
Published: October 2004

Calpain is a calciumactivated non lysosomal neutral thiol protease (EC 3.4.22.17) present in a wide variety of eukaryotic cells. Calpain is usually present as an inactive form and is activated by calcium ions and phospholipids. The ability of calpain to alter, by limited proteolysis, the activity or function of numerous cytoskeletal proteins, enzymes, and receptors suggests its involvement in various Ca2+ regulated cellular functions. In this review we focus on the differentiation of mesenchymal stem cells, such as the myoblastic, osteoblastic, chondrocytic, and adipocytic lineages, and the biological significance of calpain in its regulation. Calpain has been implicated in the differentiation of myoblasts through the turnover of glycoproteins. In preosteoblastic cells, calpain is important in mediating the proliferative and prodifferentiating effects of parathyroid hormone and bone morphogenetic proteins. For the differentiation of chondrocytes, calpain is involved in cartilagematrix mineralization. Furthermore, calpain is required for the differentiation of 3T3-L1 preadipocytes into adipocytes, involving the transcriptional activation of the C/EBPα gene and the degradation of the cyclindependent kinase inhibitor p27 during the mitotic clonal expansion phase of adipocyte differentiation. We summarize these regulatory effects of calpain on the differentiation of mesenchymal stem cells and speculate on the function and location of calpain in the differentiation processes.
Selective Release of Calpain Produced αII-Spectrin (α-Fodrin) Breakdown Products by Acute Neuronal Cell Death
Authors: Dutta Satavisha , Chiu Yuk Chun , Probert Albert W. , Wang Kevin K.W.
Published: October 2004

Activation of calpain results in the breakdown of α II spectrin (αfodrin), a neuronal cytoskeleton protein, which has previously been detected in various in vitro and in vivo neuronal injury models. In this study, a 150 kDa spectrin breakdown product (SBDP150) was found to be released into the cellconditioned media from SHSY5Y cells treated with the calcium channel opener maitotoxin (MTX). SBDP150 release can be readily quantified on immunoblot using an SBDP150- specific polyclonal antibody. Increase of SBDP150 also correlated with cell death in a timedependent manner. MDL28170, a selective calpain inhibitor, was the only protease inhibitor tested that significantly reduced MTXinduced SBDP150 release. The cellconditioned media of cerebellar granule neurons challenged with excitotoxins (NMDA and kainate) also exhibited a significant increase of SBDP150 that was attenuated by pretreatment with an NMDA receptor antagonist, R()-3-(2-carbopiperazine-4-yl)propyl-1- phosphonic acid (CPP), and MDL28170. In addition, hypoxic/hypoglycemic challenge of cerebrocortical cultures also resulted in SBDP150 liberation into the media. These results support the theory that an antibody based detection of SBDP150 in the cellconditioned media can be utilized to quantify injury to neural cells. Furthermore, SBDP150 may potentially be used as a surrogate biomarker for acute neuronal injury in clinical settings.
Effect of Cysteine Proteinase Inhibitors on Murine B16 Melanoma Cell Invasion in vitro
Authors: Sever Natasa , Filipic Metka , Brzin Joze , Lah Tamara T.
Published: October 2004

Various types of proteinases are implicated in the malignant progression of human and animal tumors. Proteinase inhibitors may therefore be useful as therapeutic agents in antiinvasive and antimetastatic treatment. The aims of this study were (1) to estimate the relative importance of proteinases in B16 cell invasion in vitro using synthetic, classspecific proteinase inhibitors and (2) to assess the inhibitory effect of some naturally occurring cysteine proteinase inhibitors. Serine proteinase inhibitor reduced invasiveness by up to 24%, whereas inhibition of aspartic proteinases reduced invasion by 11%. Synthetic inhibitors of cysteine proteinases markedly impaired invasion: cathepsin B inhibitors, particularly Ca 074Me, inhibited invasion from 20 40%, whereas cathepsin L inhibitor Clik 148 reduced invasion by 11%. The potato cysteine proteinase inhibitor PCPI 8.7 inhibited invasion by 21%, whereas another potato inhibitor, PCPI 6.6, and the mushroom cysteine proteinase inhibitor clitocypin had no effects. As the inhibitors that inhibited cathepsin B were in general more efficient at impairing the invasiveness, we conclude that of the two cysteine proteinases, cathepsin B plays a more important role than cathepsin L in murine melanoma cell invasion.
Design of Inhibitors for Human Tissue Kallikrein Using Non-Natural Aromatic and Basic Amino Acids
Authors: Pimenta Daniel C. , Melo Robson L. , Caliendo Giuseppe , Santagada Vincenzo , Fiorino Ferdinando , Severino Beatrice , Nucci Gilberto de , Juliano Luiz , Juliano Maria A.
Published: October 2004

We explored the unique substrate specificity of the primary S1 subsite of human urinary kallikrein (hK1), which accepts both Phe or Arg synthesizing and assaying peptides derived from PhenylacetylPheSer ArgEDDnp, a previously described inhibitor with analgesic and antiinflammatory activities [Emim et al., Br. J. Pharmacol. 130 (2000), 1099 1107]. Phe was substituted by amino acids containing larger aliphatic or aromatic side chains as well as by nonnatural basic amino acids, which were designed to combine a large hydrophobic and/or aromatic group with a positivelycharged group at their side chains. In general, all peptides with basic amino acids represented better inhibitors than those with hydrophobic amino acids. Furthermore, the S1 subsite specificity proved to be much more selective than the mere distinction between Phe and Arg, for minor differences in the side chains of the nonnatural amino acids resulted in major differences in the Ki values. Finally, we present a series of peptides that were assayed as competitive inhibitors for human tissue kallikrein that may lead to the development of novel peptides, which are both more potent and selective.
Novel Secretory Vesicle Serpins, Endopin 1 and Endopin 2: Endogenous Protease Inhibitors with Distinct Target Protease Specificities
Authors: Hook V. Y. H. , Hwang S.-R.
Published: October 2004

Secretory vesicles of neuroendocrine cells possess multiple proteases for proteolytic processing of proteins into biologically active peptide components, such as peptide hormones and neurotransmitters. The importance of proteases within secretory vesicles predicts the presence of endogenous protease inhibitors in this subcellular compartment. Notably, serpins represent a diverse class of endogenous protease inhibitors that possess selective target protease specificities, defined by the reactive site loop domains (RSL). In the search for endogenous serpins in model secretory vesicles of neuroendocrine chromaffin cells, the presence of serpins related to α1-antichymotrypsin (ACT) was detected by Western blots with antiACT. Molecular cloning revealed the primary structures of two unique serpins, endopin 1 and endopin 2, that possess homology to ACT. Of particular interest was the observation that distinct RSL domains of these new serpins predicted that endopin 1 would inhibit trypsinlike serine proteases cleaving at basic residues, and endopin 2 would inhibit both elastase and papain that represent serine and cysteine proteases, respectively. Endopin 1 showed selective inhibition of trypsin, but did not inhibit chymotrypsin, elastase, or subtilisin. Endopin 2 demonstrated crossclass inhibition of the cysteine protease papain and the serine protease elastase. Endopin 2 did not inhibit chymotrypsin, trypsin, plasmin, thrombin, furin, or cathepsin B. Endopin 1 and endopin 2 each formed SDSstable complexes with target proteases, a characteristic property of serpins. In neuroendocrine chromaffin cells from adrenal medulla, endopin 1 and endopin 2 were both localized to secretory vesicles. Moreover, the inhibitory activity of endopin 2 was optimized under reducing conditions, which required reduced Cys-374; this property is consistent with the presence of endogenous reducing agents in secretory vesicles in vivo. These new findings demonstrate the presence of unique secretory vesicle serpins, endopin 1 and endopin 2, which possess distinct target protease selectivities. Endopin 1 inhibits trypsinlike proteases; endopin 2 possesses crossclass inhibition for inhibition of papainlike cysteine proteases and elastaselike serine proteases. It will be of interest in future studies to define the endogenous protease targets of these two novel secretory vesicle serpins.
Cathepsin B Stability, But Not Activity, Is Affected in Cysteine:Cystine Redox Buffers
Authors: Pillay C. S. , Dennison C.
Published: October 2004

In order to test the hypothesis that the lysosomal cysteine protease cathepsin B may be redox regulated in vivo, cathepsin B activity and stability were measured in cysteine and/or cystinecontaining buffers. Cathepsin B activity in cysteinecontaining buffers was similar at pH 6.0 and pH 7.0, over all thiol concentrations tested. In contrast, the stability of the enzyme was greater at pH 6.0 than at pH 7.0. This suggests that the enzymes operational pH in vivo may be < pH 7.0. The activity of the enzyme was depressed in glutathionecontaining buffers. When assessed in cysteine:cystine redox buffers (pH 6.0 7.0) cathepsin B was active over a broad redox potential range, suggesting that cathepsin B activity may not be redox regulated. However, at pH 7.0, the stability of cathepsin B decreased with increasing reduction potential and ambient cystine concentration. This suggests that the stability of the enzyme at neutral pH is dependent on redox potential, and on the presence of oxidising agents.
Reverse Genetic Analysis of the Caenorhabditis elegans 26S Proteasome Subunits by RNA Interference
Authors: Takahashi M. , Iwasaki H. , Inoue H. , Takahashi K.
Published: October 2004

Reverse genetic analysis was performed on the Caenorhabditis elegans 26S proteasome subunit genes by doublestranded RNAmediated interference (RNAi). Embryonic and postembryonic lethality was caused by interference of all of the eight tested 20S core subunits and all of the 19S regulatory particle subunits except for CeRpn9, CeRpn10, and Ce Rpn12, where RNAi caused no abnormality. However, synthetic suppression of CeRpn10 and CeRpn12 was lethal, whereas neither the combination of Ce Rpn9 with CeRpn10 nor with CeRpn12 resulted in abnormalities in RNAi. These results indicate that the 26S proteasome is indispensable for embryogenesis and postembryonic development, although Ce Rpn9, CeRpn10, and CeRpn12 are not essential, at least under the conditions used. CeRpn10 and Ce Rpn12 are considered to compensate for the suppression of each other.
Functional Consequences of Cathepsin L Deficiency in Human Lung Epithelial Cells
Authors: Wille A. , Heimburg A. , Gerber A. , Reisenauer A. , Welte T. , Bühling F.
Published: October 2004

Cathepsin L is a cysteine protease of the papain family. Lung epithelial cells play an important role in host defence. The aim of the present study was to investigate the functional role of cathepsin L in the human lung carcinoma cell line A549. Cathepsin Ldeficient A549 clones were generated. They showed a significant lower proliferation and secreted 5- to 8-fold more IL-8 than the control cells. The production of IL 6, IL-18, and TGFβ1/2 was not affected significantly. It was shown that the cells upregulate IL-8 transcription and that IL-8 in the culture supernatant is necessary for the containment of cellular proliferation. In conclusion, the data show that suppression of cathepsin L expression in A549 cells leads to a growth inhibition which is partially compensated by an upregulation of IL-8 production.
Kaposis Sarcoma and Human Chorionic Gonadotropin: Mechanisms, Moieties and Mysteries
Authors: Bisacchi D. , Noonan D. M. , Carlone S. , Albini A. , Pfeffer U.
Published: October 2004

Kaposis Sarcoma (KS) is a highly angiogenic neoplasm associated with infection by the human γherpesvirus, HHV-8 or Kaposis sarcoma herpes virus (KSHV). When in 1872 the Hungarian scientist Moritz Kaposi described the sarcoma, which was later named after him, he was dealing with a rare dermatologic disease. Today, KS is a more common pathology due to its high incidence in AIDS, in immunosuppressed transplantation patients and, in its endemic form, in Africa. The introduction of highly active antiretroviral therapy (HAART) has led to a drastic reduction of KS incidence in HIVinfected patients, but in some cases KS resists the treatment. KS is more common in men than in women. The observation of spontaneous remissions during pregnancy stimulated investigations into the potential antiKS activity of the pregnancy hormone human chorionic gonadotropin (hCG). The variable effect in clinical trials using urinary preparations of the hormone (uhCG) has led to the hypothesis that contaminating moieties present in these preparations may account for the antiKS effect observed in vitro. While the discrepancy between laboratory tests and clinical trials remains a mystery, little is known about potential antiKS mechanisms of the hormone itself and/or other active moieties present in uhCG.
Lipid Rafts in Protein Sorting and Cell Polarity in Budding Yeast Saccharomyces cerevisiae
Authors: Bagnat M. , Simons K.
Published: October 2004

Cellular membranes contain many types and species of lipids. One of the most important functional consequences of this heterogeneity is the existence of microdomains within the plane of the membrane. Sphingolipid acyl chains have the ability of forming tightly packed platforms together with sterols. These platforms or lipid rafts constitute segregation and sorting devices into which proteins specifically associate. In budding yeast, Saccharomyces cerevisiae, lipid rafts serve as sorting platforms for proteins destined to the cell surface. The segregation capacity of rafts also provides the basis for the polarization of proteins at the cell surface during mating. Here we discuss some recent findings that stress the role of lipid rafts as key players in yeast protein sorting and cell polarity.
Protein Transduction: A Novel Tool for Tissue Regeneration
Authors: Cardoso M. C. , Leonhardt H.
Published: October 2004

Tissue regeneration in humans is limited and excludes vitals organs like heart and brain. Transformation experiments with oncogenes like T antigen have shown that retrodifferentiation of the respective cells is possible but hard to control. To bypass the risk of cancer formation a protein therapy approach has been developed. The transient delivery of proteins rather than genes could still induce terminallydifferentiated cells to reenter the cell cycle. This approach takes advantage of proteintransducing domains that mediate the transfer of cargo proteins into cells. The goal of this brief review is to outline the basics of protein transduction and to discuss potential applications for tissue regeneration.
Processing and Activation of Lysosomal Proteinases
Authors: Ishidoh K. , Kominami E.
Published: October 2004

Lysosomal proteinases are translated as preproenzymes, transferred through the Golgi apparatus as proenzymes, and localized in lysosomes as the mature enzymes. Pulsechase analyses and the immunoisolation of proenzymes or recombinant proenzymes are useful tools for analyzing this process, but the processing proteinases that participate in this pathway are largely unknown. Recently, we developed a new method for analyzing processing proteinases using Bafilomycin A1 and proteinase inhibitors. Here we summarize the recent progress including our results obtained using this method.
The Promoter Context Determines Mutual Repression or Synergism between NF-κB and the Glucocorticoid Receptor
Authors: Hofmann T.G. , Schmitz M.L.
Published: October 2004

While the biochemical mechanisms mediating repression
of NFκB activity by glucocorticoids (GCs)
are relatively well studied, the role of promoter architecture
for the effects of GCs on NFκB remains poorly
characterized. Therefore we constructed a set of
synthetic promoter reporter constructs containing
various numbers of GCresponsive elements (GREs)
in distinct distances to NFκB binding sites. TNFαinduced
activity of a synthetic promoter controlled by
three NFκB binding sites was repressed by dexamethasone.
The presence of only one GRE in the vicinity
of the κB sites abolished this repression and allowed
synergistic transcriptional activation by NFκB
and the glucocorticoid receptor (GR). The synergism
identified here was not affected by the number of
GREs, but strictly depends on the spacing between
GREs and κB sites. These experiments reveal that the
functional interplay between NFκB and the GR also
involves dependent on the promoter context synergistic
stimulation of transcription.
The Chemical Nature of Kiln Brown Stain in Radiata Pine
Authors: McDonald Armando G. , Fernandez Marc , Kreber Bernhard , Laytner Frank
Published: October 2004

This paper presents results of a study on the chemical nature of kiln brown stain (KBS) that develops in
kiln dried radiata pine (Pinus radiata D. Don) sapwood. KBS is a chocolate brown discolouration which
develops approximately 0.5 mm under the timber surface. Stain free radiata pine was achieved during
drying trials on “green” radiata pine sapwood which had been treated to extensive cold and hot water
extraction. Differences in chemical composition between the sap and hot water extract were observed.
Chemical analyses (of the water-soluble extracts) by a combination of chromatographic and spectroscopic
techniques, demonstrated that carbohydrates, cyclitols, amino acids, protein, and phenolics were
the main compound classes present. The presence of reducing sugars (glucose and fructose) and amino
acids (glutamic acid) in the sap and hot water extracts support the theory that Amadori-Maillard type
reactions significantly contribute to the formation of colour in KBS. Furthermore, lignin was also detected
and is suspected to contribute to KBS formation. The relative contributions of colour formation to
KBS intensity from either phenolics or Maillard-Amadori mechanisms is unknown.
X-Ray Diffraction as an Analytical Method in Wood Preservatives
Authors: Zhang J. , Kamdem D. P.
Published: October 2004

X-ray diffraction (XRD) technique was used to analyze qualitatively and semi-quantitatively solid crystal
deposits in wood treated with some preservatives. Chromated copper arsenate type-C (CCA), copper
ethanolamine (Cu-EA), copper naphthenate (Cu-N), copper dimethyldithiocarbamate (CDDC) and boric
acid treated southern pine was investigated. The solid deposit in post-treatment steamed Cu-N and Cu-EA treated wood samples was identified as cuprous oxide (Cu2O) by using XRD. The presence of CDDC
crystals was observed in CDDC treated wood samples. The XRD pattern of boric acid treated wood
shows that crystalline boric acid is present in the treated wood. After washing boric acid treated wood
with distilled water, the crystalline signal of boric acid disappeared. An XRD technique was also developed
to semi-quantify the amount of solid crystals in post-treatment steamed Cu-N treated and CDDC
treated samples. It was estimated that about 50% of cupric copper was converted to cuprous oxide
(Cu2O) in Cu-N treated wood after post treatment steaming whereas no cuprous oxide was found in non
post-treatment steamed Cu-N treated samples. The CDDC content determined by XRD was consistently
10–20% lower than the value calculated from the copper content using atomic absorption spectroscopy
(AAS) analysis.
Preparation of Wood with Thermoplastic Properties, Part 2. Simplified Technologies
Authors: Timar Maria Cristina , Maher Kevin , Irle Mark , Mihai Maria Daniela
Published: October 2004

Aspen wood (Populus tremula) as sawdust was chemically modified through a two-step procedure: esterification with maleic anhydride and subsequent oligoesterification with glycidyl methacrylate and maleic anhydride. Simplified techniques consisting of impregnation by immersion followed by thermal treatment using conventional or microwave heating were employed. Chemical analyses and infra-red spectroscopy showed some differences in the chemical composition and structure of the resulting oligoesterified wood depending on the synthesis technique. However, the thermoplastic properties, clearly revealed by thermomechanical analysis, were quite similar and comparable to those exhibited by the oligoesterified wood resultingviaclassical synthesis. Moreover, similar degrees of chemical modification were obtained for a significantly shorter duration of the process when microwave heating was employed instead of conventional heating.
The Effect of Hydrostatic Pressure on Physical Properties and Microstructure of Spruce and Cherry
Authors: Bucur Voichita , Garros Simone , Barlow Claire Y.
Published: October 2004

The effect of hydrostatic pressure on the density, the ultrasonic velocities and the microstructure of
spruce and cherry wood has been studied. Generally speaking, under hydrostatic pressure wood becomes
less heterogeneous and less anisotropic than natural wood. In spruce, crushing and buckling of the thin-walled
cells in the earlywood takes place. This also has the effect of disrupting the medullary rays, which
assume a zig-zag path through the structure. Cherry has a much more homogeneous structure, and the
main effect of the hydrostatic pressure is compaction of the vessels by buckling of the walls. The fibres
are scarcely affected by the treatment. The width of the earlywood zone decreased after the application
of pressure by 26% in spruce, and by 11% in cherry. The average density was increased by the hydrostatic
pressure by 26% for spruce and by 46% for cherry. The densitometric profile of spruce demonstrates
significant changes following the pressure treatment, with the minimum density DMin increasing
and the maximum density DMax decreasing. For cherry, the densitometric profile is shifted rather uniformly
towards higher densities, and the annual ring profile is spatially slightly compacted but otherwise
similar to that of untreated wood. The anisotropy of wood (expressed by the ratio of acoustic invariants)
decreased by 56% for spruce and by 33% for cherry. The structural damage in spruce is predominantly
found in the radial (R) direction, and this corresponds to a reduction of 73% in the velocity of the longitudinal
ultrasonic waves in the radial direction, VRR. In cherry, the structural damage is mainly in the
transverse, T direction. The velocity of the longitudinal ultrasonic waves in the transverse direction, VTT
is reduced by 44%. The medullary rays in cherry seem to be the most important anatomical feature influencing
the propagation of ultrasonic waves.
Application of Liquefied Wood to a New Resin System—Synthesis and Properties of Liquefied Wood/Epoxy Resins
Authors: Kobayashi Masahiko , Tukamoto Kyoko , Tomita Bunichiro
Published: October 2004

A new resin system was developed by reacting liquefied wood with various epoxy compounds. Examination
of the optimum conditions for the synthesis of the resins, and the behavior of liquefied wood in
the cured resins were undertaken. Generally, the compatibility and film forming performance of liquefied
wood/epoxy resins became better as the wood content increased. The presence of only one broad
dispersion peak, due to the glass transition, was observed during dynamic mechanical measurement of
resin films suggesting that the different components of the resin were compatible. The glass transition
temperature of the cured resins could be modified by changing the kinds of epoxy compounds and the
wood contents of liquefied wood. The presence of rubber elasticity at higher temperatures suggests that
the resin systems consisted of cross-linking polymer networks.
FTIR Characterization of Copper Ethanolamine—Wood Interaction for Wood Preservation
Authors: Zhang Jun , Kamdem D. Pascal
Published: October 2004

The interaction of copper ethanolamine (Cu-EA) preservative and wood components was studied by
using Fourier transform infrared spectroscopy (FTIR). In Cu-EA treated wood, significant reduction was
noticed on the band attributed to carbonyl vibration from carboxylic groups at 1735 ± 5 cm−1 and an
increase in band intensity was obtained from carbonyl in carboxylate at 1595 ± 5 cm−1. The same observation
was made in Cu-EA treated holocellulose. Cu-EA treated lignin resulted in a reduction in the aromatic
ester band at 1710 ± 5 cm−1 and an increase in carbonyl from carboxylate at 1595 ± 5 cm−1. Bands
at 1370 cm−1 and 1221 cm−1, assigned to phenolic hydroxyl groups, exhibited a decrease in intensity after
the treatment. From these data, it is concluded that Cu-EA interacts with carboxylic groups, phenolic
hydroxyl groups and ester groups from lignin to form copper carboxylate and phenolate complexes.
Cation Exchange Capacity Tests on Some Lignocellulosic Materials Highlight Some Aspects of the Use of Copper as Wood Preservative
Authors: Staccioli Giuseppe , Sturaro Alberto , Rella Rocco
Published: October 2004

The stoichiometric validity of copper(II) salts in the assessing the cation exchange capacity of lignocellulosic
materials with respect to sodium salts is determined on some materials like Populus euramericana,
Pinus pinea, flax, hemp, cotton, and some of their derivatives.

Copper exhibits the usual stoichiometry (bivalence) with saponified woods and Norman & Jenkins
holocelluloses whereas it is present as bivalent and/or apparent monovalent ions in the other materials.
The major groups responsible for cation exchange are the carboxyls of polyoses while hydroxyls seem
inert at this reaction. Cation exchange of wood and raw fibers is, on the contrary, influenced by the structure
of lignin. In fact, when it forms ester bonds with polyoses it causes the rising of copper apparently
working as monovalent species. Lacking these bonds, lignin does not provoke any chemical interactions
except for some isolated lignins. These data show that copper interacts mainly with polyoses, secondly
with lignin if bonded to polyoses whereas cellulose seems to be weakly involved in these interactions.

To improve the assumption of copper from preservative formulations mild saponification of woods is
suggested since such treatment enhances the number of sites of exchange in polyoses.
Biological, Chemical and Mechanical Characteristics of "Wulstholz" as a Response to Mechanical Stress in Living Trees of Picea abies [L.] Karst
Authors: Koch G. , Bauch J. , Puls J. , Schwab E.
Published: October 2004

In the present study, the biological, chemical and mechanical wood properties of “Wulstholz” as a
response to mechanical stress of spruce trees (Picea abies [L.] Karst.) were investigated. “Wulstholz” is
formed locally on the compression side of overstressed tree trunks after slip planes were initiated. It is
characterized by an increased xylem production leading to bulges. The S2-layers of “Wulstholz”-tracheids
are thicker than the corresponding cell wall layers in normal wood, and the cell lumen diameter
is significantly reduced. The tracheid length decreases gradually from an average of 4 mm to 2.5 mm
compared to normal wood, and the tracheids conspicuously are shifted against each other longitudinally.
“Wulstholz” contains a higher concentration of lignin than normal wood, whereas the concentration
of glucose in the hydrolysates is reduced. The hemicelluloses-concentration, particularly the mannose-content,
is significantly higher compared to normal wood. The compression strength and the modulus of
elasticity, despite a higher density, are significantly reduced in “Wulstholz” in comparison to normal
wood. But due to the specific anatomical and chemical properties, “Wulstholz”-tracheids can be
deformed and compressed considerably without fracturing. The investigations demonstrate that “Wulstholz”
can restabilize wind-exposed trees.
Kinetic Studies on Oxidation of Veratryl Alcohol by Laccase-Mediator System. Part 2. The Kinetics of Dioxygen Uptake
Authors: Balakshin Mikhail Yu. , Chen Chen-Loung , Gratzl Josef S. , Kirkman Adrianna G. , Jakob Harald
Published: October 2004

The kinetics of dioxygen uptake in the laccase-catalyzed oxidation of veratryl alcohol with dioxygen in the presence of ABTS, the mediator, was studied. The kinetics of dioxygen uptake consists of two phases: (1) the initial phase up to a reaction time of one hour, and (2) the second phase, after a reaction time of one hour. In the initial phase, ABTS is mainly oxidized to the corresponding cation radical. The kinetics of dioxygen uptake follows apseudo-zero order rate law. The dioxygen uptake under the reaction condition correlates with the initial ABTS concentration according to the stoichiometric relationship of 0.25 moles dioxygen per mole ABTS. In the second phase, veratryl alcohol is mainly oxidized to veratraldehyde. The kinetics of the dioxygen uptake follows apseudo-first order rate law. The dioxygen uptake correlates linearly with the yield of veratraldehyde. The stoichiometric ratio between the formation of veratraldehyde and the consumption of dioxygen differs slightly at different M/S ratios. On average, however, it is 0.42 moles of dioxygen per one mole of veratraldehyde formed. The reaction mechanism is discussed on the basis of the kinetic data.
A New Air Dehydration Process for Wood Dryers. Part I. Kinetic and Quality of Drying
Authors: Chrusciel L. , Mougel E. , Zoulalian A.
Published: October 2004

In conventional wood dryers, air is dehumidified by condensation or by its partial remove. A new air
dehydration process is proposed for low temperature convective wood drying. This process consists in
using an absorber working with an organic absorbent, the triethylene glycol (TEG) that is pulverised in
a venturi type of device. The adaptation of this process well known for hydrocarbon gas dehydration and
its interest for wood drying operations are discussed. The prototype installation is presented and the
impact of the absorption on the evolution on drying cycles are investigated. The performances of the
absorber are evaluated quantitatively and qualitatively. The average drying kinetic is quantified with a
global mass transfer coefficient and the drying quality is characterised through the measurements of
defects generated during drying.
A New Method of Sample Preparation for Kenaf Bast Fiber Length Analysis with Automated Fiber Length Analyzer
Authors: Cheng Zhou , Fujiwara Shinji , Ohtani Yoshito , Sameshima Kazuhiko
Published: October 2004

Kenaf bast fiber bundles alternate radially in layers accompanied by sieve elements and phloem
parenchyma cells. Fiber bundles are about 20 % in the area of a cross section of kenaf bast. Four sample
preparation methods for kenaf bast fiber length analysis with an automated fiber length analyzer were
compared and a new sample preparation method including three steps was proven to be accurate. Fiber
bundles were obtained by acidified sodium chlorite treatment and an additional ammonium oxalate
treatment. Following a 1% sodium hydroxide treatment, fiber bundles were completely separated into
single fibers with no damage. Fiber length values of this method were more accurate and reliable than
other three sample preparation methods and manual measurement with optical microscope.
The Effects on Place Cells of Local Scopolamine Dialysis Are Mimicked by a Mixture of Two Specific Muscarinic Antagonists
Authors: Brazhnik Elena , Borgnis Ramie , Muller Robert U. , Fox Steven E.
Published: October 2004

Using a dialysis probe near CA1 hippocampal recording electrodes, we infused nonspecific (scopolamine) and specific (methoctramine, pirenzepine) antagonists of muscarinic cholinergic transmission to determine their effects on the positional firing properties of place cells. Both low (0.5 mm) and high (2.0 or 3.0 mm) scopolamine significantly decreased in-field firing rate, increased the ratio of out-of-field to in-field rate, and reduced the smoothness of rate maps, while tending to increase out-of-field rate. Thus, local nonspecific muscarinic blockade mimicked the effects seen with intracerebroventricular application, suggesting that blockade of receptors local to the recorded cells plays an essential role. Unexpectedly, dialysis of scopolamine reduced locomotor activity, again duplicating the effects of intracerebroventricular administration. Most effects of methoctramine (1.0 mm), which blocks presynaptic m2and m4receptors, were initially strong but then diminished over hours. Methoctramine produced a significant increase only in out/in ratio and out-of-field rate, whereas it tended to increase in-field rate and monotonically decrease smoothness. Pirenzepine (3.0 mm), which blocks postsynaptic m1receptors, produced a significant increase only in out/in ratio, whereas it tended to increase out-of-field rate and decrease in-field rate; all these effects were monotonic with respect to time. A mixture of methoctramine plus pirenzepine recapitulated the place-cell effects of scopolamine, although neither the mixture nor its separate components affected behavior. We conclude that the effects of scopolamine on place cells likely result from a combination of blockade of postsynaptic m1receptors, leading to reduced excitability, with blockade of presynaptic m2and m4receptors, leading to increased out-of-field firing.
Cranial Afferent Glutamate Heterosynaptically Modulates GABA Release onto Second-Order Neurons via Distinctly Segregated Metabotropic Glutamate Receptors
Authors: Jin Young-Ho , Bailey Timothy W. , Andresen Michael C.
Published: October 2004

The balance between excitation and inhibition dictates central integration. Glutamatergic and GABAergic neurotransmission dominate this process. Cranial primary afferents enter the brainstem to release glutamate (Glu) onto second-order neurons within the caudal nucleus tractus solitarius (NTS) to initiate autonomic reflexes. The simplest pathways for these reflexes contain as few as two central neurons, but display robust frequency-dependent behavior. Within NTS, multiple metabotropic Glu receptors (mGluRs) are present, but their roles are poorly understood. Using synaptically discriminated second-order NTS neurons in brainstem slices and mechanically dissociated NTS neurons with intact boutons, we show that Glu differentially controls GABA release via distinct presynaptic mGluRs. In second-order NTS neurons recorded in slices, activation of primary afferents at frequencies as low as 10 shocks per second released sufficient Glu to alter rates of spontaneous IPSCs (sIPSCs). In both approaches, group I mGluRs increased GABA release in some neurons, but, on different neurons, group II and group III mGluRs decreased the sIPSC rate. mGluR actions were remarkably rapid, with onset and reversal beginning within 100 msec. In all cases, mGluR actions were exclusively presynaptic, and mGluRs did not alter postsynaptic properties in second-order neurons in either slices or isolated neurons. Tests with capsaicin and αβ-methylene ATP suggest that myelinated and unmyelinated afferent pathways engage both mGluR-GABA mechanisms. Afferent Glu spillover provides heterosynaptic cross talk with GABAergic inhibition in NTS. This process may critically shape the dynamic character and use dependence for cranial afferent transmission at the first stage of autonomic reflexes.
Astrocyte-Associated Fibronectin Is Critical for Axonal Regeneration in Adult White Matter
Authors: Tom Veronica J. , Doller Catherine M. , Malouf Alfred T. , Silver Jerry
Published: October 2004

Although it has been suggested that astroglia guide pioneering axons during development, the cellular and molecular substrates that direct axon regeneration in adult white matter have not been elucidated. We show that although adult cortical neurons were only able to elaborate very short, highly branched, dendritic-like processes when seeded onto organotypic slice cultures of postnatal day 35 (P35) rat brain containing the corpus callosum, adult dorsal root ganglion (DRG) neurons were able to regenerate lengthy axons within the reactive glial environment of this degenerating white matter tract. The callosum in both P35 slices and adult rat brain was rich in fibronectin, but not laminin. Furthermore, the fibronectin was intimately associated with the intratract astrocytes. Blockade of fibronectin functionin situwith an anti-fibronectin antibody dramatically decreased outgrowth of DRG neurites, suggesting that fibronectin plays an important role in axon regeneration in mature white matter. The critical interaction between regrowing axons and astroglial-associated fibronectin in white matter may be an additional factor to consider when trying to understand regeneration failure and devising strategies to promote regeneration.
Dynamic Sound Localization during Rapid Eye-Head Gaze Shifts
Authors: Vliegen Joyce , Van Grootel Tom J. , Van Opstal A. John
Published: October 2004

Human sound localization relies on implicit head-centered acoustic cues. However, to create a stable and accurate representation of sounds despite intervening head movements, the acoustic input should be continuously combined with feedback signals about changes in head orientation. Alternatively, the auditory target coordinates could be updated in advance by using either the preprogrammed gaze-motor command or the sensory target coordinates to which the intervening gaze shift is made (“predictive remapping”). So far, previous experiments cannot dissociate these alternatives. Here, we study whether the auditory system compensates for ongoing saccadic eye and head movements in two dimensions that occur during target presentation. In this case, the system has to deal with dynamic changes of the acoustic cues as well as with rapid changes in relative eye and head orientation that cannot be preprogrammed by the audiomotor system. We performed visual-auditory double-step experiments in two dimensions in which a brief sound burst was presented while subjects made a saccadic eye-head gaze shift toward a previously flashed visual target. Our results show that localization responses under these dynamic conditions remain accurate. Multiple linear regression analysis revealed that the intervening eye and head movements are fully accounted for. Moreover, elevation response components were more accurate for longer-duration sounds (50 msec) than for extremely brief sounds (3 msec), for all localization conditions. Taken together, these results cannot be explained by a predictive remapping scheme. Rather, we conclude that the human auditory system adequately processes dynamically varying acoustic cues that result from self-initiated rapid head movements to construct a stable representation of the target in world coordinates. This signal is subsequently used to program accurate eye and head localization responses.