bluuebunny/crossref_metadata_2025 huggingface dataset:
PKC expression is regulated by dietary K intake and mediates internalization of SK channels in the CCD
Authors: Sterling Hyacinth , Lin Dao-Hong , Chen Yu-Jung , Wei Yuan , Wang Zhi-Jian , Lai Jian , Wang Wen-Hui
Published: May 2004

We have used Western blot analysis and immunocytochemistry to determine the effect of dietary K intake on the expression of protein kinase C (PKC) isoforms in the kidney. Western blot has demonstrated that conventional PKC isoforms (α and β), novel PKC isoforms (δ, ε, and η), and atypical PKC isoforms (ζ) are expressed in the renal cortex and outer medulla. Moreover, a low K intake significantly increases the expression of PKC-ε in the renal cortex and outer medulla but does not change the expression of PKC-α, PKC-β, PKC-δ, PKC-η, and PKC-ζ. Also, immunocytochemistry shows that PKC-ε isoform is expressed in the cortical collecting duct (CCD) and outer medullary collecting duct (OMCD) and that the intensity of PKC-ε staining is higher in the kidney from rats on a K-deficient diet than those on a control diet. Also, we used the patch-clamp technique to study the role of PKC in mediating internalization of ROMK (Kir 1.1)-like small-conductance K (SK) channels induced by phenylarsine oxide (PAO), an agent that inhibits protein tyrosine phosphatase and has been shown to stimulate the internalization of the SK channel in the CCD (Sterling H, Lin DH, Qu RM, Dong K, Herbert SC, and Wang WH. J Biol Chem 277: 4317–4323, 2002). Inhibition of PKC with calphostin C and GF-109203x had no significant effect on channel activity but abolished the inhibitory effect of PAO on SK channels. In conclusion, a low K intake increases the expression of PKC-ε isoform in the renal cortex and outer medulla, and PKC is involved in mediating the internalization of SK channels in the CCD induced by stimulation of protein tyrosine kinase activity.
The pathophysiology of cancer-induced bone pain: current understanding
Authors: Urch Catherine
Published: May 2004

Cancer-induced bone pain (CIBP) is a common clinical problem. Although treatment has been revolutionised in the past 10 years with the introduction of bisphosphonates, pain arising spontaneously or from movement, remains a leading cause of unresolved pain in many patients. Until recently little was understood about the peripheral and central mechanisms of bone pain. Insight into the mechanisms of osteoblast and osteoclast activation, via receptor activator for nuclear factor kB (RANK) dependent and independent mechanisms and a re-evaluation of primary afferent terminals within bone have led to a suggestion that CIBP may be a mixture of inflammatory and neuropathic stimuli. The recently published animal model of localised but progressive bone destruction has allowed greater insight into the peripheral and dorsal horn pathophysiology, which hitherto was precluded. Immunocytochemical markers of neurotransmitters and receptors indicate that CIBP has unique characteristics, unlike neuropathy or inflammation. Evidence for an increased excitability within the dorsal horn, and especially Lamina I, and possible mechanisms underlying this unique pain state will be discussed.
Removing the boundaries: palliative care for patients with heart failure
Authors: Horne Gillian , Payne Sheila
Published: May 2004

Aim: This study aimed to explore the experiences of patients with severe heart failure and identify their needs for palliative care. Method: A qualitative design was chosen. Semistructured interviews were used for data collection and patients were interviewed in their homes. The sample consisted of 20 patients with a confirmed diagnosis of heart failure. Patients were between 60 and 83 years. Results: Patients reported difficulties in walking, extreme fatigue and problems managing daily activities. Having to rely on family, friends and neighbours was common, causing feelings of being a burden, loneliness and isolation. Patients talked about dying as well as their fears and frustrations in living with heart failure. Barriers to accessing information and social services were identified. None of these patients had been referred to specialist palliative care services. Conclusions: Patients' experiences were similar to those of patients living with advanced cancer and yet they received little support. Comprehensive routine assessment of the palliative care needs of patients living with severe heart failure is recommended.
Estimation of Downtime-Related Revenue Losses in Seaports following Scenario Earthquakes
Authors: Pachakis Dimitris , Kiremidjian Anne S.
Published: May 2004

Seaports are critical nodes in regional transportation networks and can have important impact to the local economy. During recent earthquakes, seaports have demonstrated that they can be highly vulnerable to seismic motion and associated ground failures, and their poor seismic performance has resulted in billions of dollars of losses. In order to make informed decisions concerning the design, expansion, and retrofit of port facilities, it is important to forecast the economic and operational outcome after such events. In this paper, the authors present a methodology to assess probabilistically the operational losses in multiterminal container ports after scenario earthquakes via simulation. For this purpose, a port operations simulation model is developed and is applied to various single and multiterminal examples. It is shown that parameters like the total downtime and the correlation between the damage states in different structures can significantly affect the losses. It is also shown that proper post-earthquake operation strategies can minimize the total operational loss.
Seismic Behavior of Wood-framed Structures with Viscous Fluid Dampers
Authors: Symans Michael D. , Cofer William F. , Du Ying , Fridley Kenneth J.
Published: May 2004

The suitability of viscous fluid dampers for seismic protection of light-framed wood buildings is investigated in this paper. Nonlinear finite-element models of wood building components (shear wall) and systems (three-dimensional buildings) are developed and numerical analyses are performed to evaluate their response to seismic loading. For both the single wall and the building system, seismic protection is provided by installing viscous fluid dampers within the wall cavities. The results of the numerical analyses demonstrate the ability of fluid dampers to dissipate a significant portion of seismic input energy, reducing the inelastic strain energy demand on the wood framing system. In addition, the study revealed some important practical issues associated with implementation of fluid dampers within light wood-framed buildings.
Unsymmetrical shear loading and its influence on the frictional shakedown of incomplete contacts
Authors: Dini D , Hills D A
Published: May 2004

Although incomplete contacts can never shake down to a completely adhered state, the self-development of residual frictional shearing tractions can reduce significantly the size of the slip zone. This phenomenon is demonstrated using the Hertz-Cattaneo contact.
Thermomechanical modelling and force analysis of friction stir welding by the finite element method
Authors: Chen C , Kovacevic R
Published: May 2004

Friction stir welding (FSW) is a solid-state jointing technology, in which the butted plates are heated, plasticized and jointed locally by the plunged probe and shoulder moving along the joint line. The residual stresses due to the thermomechanical performance of the material and the constraint of the welded plates by the fixture are one of main concerns for this process. A prediction of the clamping force applied on the plates during FSW is expected to be helpful in controlling the residual stresses and weld quality. Furthermore, the prediction of the force history in FSW will be beneficial to understand the mechanics of the process and to provide valid models for controlling the process, especially in the case of robotic FSW. In this paper, a three-dimensional model based on a finite element method is proposed to study the thermal history and stress distribution in the weld and, subsequently, to compute mechanical forces in the longitudinal, lateral and vertical directions. The proposed model includes a coupled thermomechanical modelling. The parametric investigation of the effects of the tool rotational and longitudinal speed on the longitudinal, lateral and vertical forces is also conducted in order to compute the appropriate clamping force applied on the plates. Measurements by the load cells in the longitudinal, lateral and vertical directions are presented and reveal a reasonable agreement between the experimental results and the numerical calculations.
Modelling and simulation of residual stress and warpage in injection moulding
Authors: Li D , Zhou H
Published: May 2004

Nowadays, moulders and customers pay increasing attention to parts warpage, which becomes a determining quality criterion for parts acceptance. The accurate prediction of warpage of injection-moulded parts is an important and challenging task for numerical simulation of injection moulding. In this paper, the numerical analysis of warpage in injection-moulded parts was carried out in consideration of the residual stresses produced during both the packing and the cooling stages. For residual stress analysis, a thermorheologically simple viscoelastic material model was introduced to consider the stress relaxation effect and to describe the mechanical behaviour according to the temperature change. The deformation of injection-moulded parts induced by the residual stress was calculated on the basis of the theory of shells, represented as an assembly of flat elements formed by combining the constant strain and the discrete Kirchhoff triangular element. Experimental research on a flat plate was also performed to study the effect of mould structure and processing parameters on warpage. The simulation results were also compared with the experimental data for verification of the developed programme. It was found that the predictions were in agreement with experimental data, especially in qualitative analysis.
The development of temperature fields and powder flow during laser direct metal deposition wall growth
Authors: Pinkerton A J , Li L
Published: May 2004

The additive manufacturing technique of laser direct metal deposition (DMD) has had an impact in rapid prototyping, tooling and small-volume manufacturing applications. Components are built from metallic materials that are deposited by the continuous injection of powder into a moving melt pool, created by a defocused laser beam. The size of the melt pool, the temperature distributions around it and the powder flux are critical in determining process characteristics such as deposition rate. In this paper, the effects that changes in the distance between the laser deposition head and the melt pool have on these factors as a part is built using a coaxial powder feeding system are considered via a two-part analytical model. A heat flow model considers three-dimensional temperature distributions due to a moving Gaussian heat source in a finite volume and a simple mass-flow model considers changes in powder concentration with distance from the deposition head. The model demonstrates the effect of adjusting the melt pool standoff in different ways on melt pool and powder flow characteristics as a DMD structure is built, and hence allows the effect on build rate to be predicted. Its validity is verified by comparison with a series of 316L stainless steel walls, built using different standoff adjustment methods. The model is found to be able to explain the dimensional characteristics found.
Dominant Factors of Preventing Rhodamine 6G from Dimer Formation in Aqueous Solutions
Authors: Igarashi Kaoru , Maeda Mitsuo , Takao Takayuki , Oki Yuji , Kusama Hideaki
Published: May 2004

Rhodamine 6G/water/alcohol or carboxylic acid systems were studied. Rhodamine 6G molecules, which tend to associate into nonfluorescent dimers in aqueous solution, were prevented from dimerization by mixing them with organic compounds. It was found that additives with smaller dielectric constants prevented the dye molecules from associating to effectively form dimers. It was found that 2-butanol and isobutyric acid were the most effective additives for dissolving Rhodamine 6G dimer and that the amount demanded to obtain the necessary concentration of monomer in aqueous solution was less than 10%.
Analysis of Reactions between Crown Ethers and Alkali or Alkaline Earth Metal Cations in Aqueous Solutions by Capillary Zone Electrophoresis
Authors: Manege Ludovick C , Takayanagi Toshio , Oshima Mitsuko , Iwachido Tadashi , Motomizu Shoji
Published: May 2004

Complex formation constants of six crown ethers, benzo-12-crown-4, benzo-15-crown-5, benzo-18-crown-6, dibenzo-18-crown-6, dibenzo-21-crown-7, and dibenzo-24-crown-8 (B12C4, B15C5, B18C6, DB18C6, DB21C7, and DB24C8, respectively) with alkali and alkaline earth metal cations have been measured in aqueous solutions by capillary zone electrophoresis. The procedure involved the measurement of change in the electrophoretic mobility of the ligands upon increasing the metal ion concentration in the carrier electrolyte solution. A substantial increase in apparent electrophoretic mobility was observed for the crown ethers with increasing concentrations of the metal ions. The variations in increased electrophoretic mobility were attributed to the different stability of the complexes formed between the cations and the crown ether. The complex formation constants obtained with alkali metal cations were in the orders of: K+ > Na+ > Rb+ > Cs+ (B18C6), K+ > Na+ > Rb+ > Cs+ (DB18C6), Rb+ > Cs+ > K+ (DB21C7), and Rb+ > Cs+ (DB24C8); while with alkaline earth metal cations it was: Ba2+ > Sr2+ > Ca2+ (B18C6) and Ba2+ > Sr2+ (DB18C6). All the ligands examined showed no change in their apparent electrophoretic mobility upon changing Li+ and Mg2+ concentrations, indicating less reactivity with the cations. From the results obtained in this study, the electrophoretic method was proved to be preferable for analyzing the reactivity of the crown ethers and the selectivity toward metal cations.
Dimensiosolvatic Effects. VI. Rates of Ionization of 2-Fluoro-4,4,5,5-tetramethyl-1,3-dioxolane: Dimensiosolvatic vs. Hydrogen-Bond Effects
Authors: Oki Michinori , Ikeda Hiroshi , Toyota Shinji
Published: May 2004

The title compound was prepared by treating 4,4,5,5-tetramethyl-1,3-dioxolan-2-yl acetate with cesium fluoride. Rates of ionization of this compound were determined in various solvents by the dynamic NMR technique. While effects due to polarity as well as solvent molecular size were observed in many solvents examined, the rates in solutions of which the solvent is capable of being an acceptor in hydrogen-bond formation with the substrate were unusually small, and this effect is diminished in bulky solvents. Such results are attributed to stabilization of the original state due to hydrogen-bond formation with the acidic C(2) – H group of the substrate in those solvents. The hydrogen-bond formation is hindered by the steric effects in bulkier solvents than in smaller solvents. The rates of contact ion pair and solvent-separated ion pair formations should be independently determined in 2-fluoro-4,4,5,5-tetramethyl-1,3-dioxolane, but so far no clear example which shows that the rate-limiting step is the solvent intervention has been found, even though various bulky solvents were examined.
A Novel Catalysis of [{IrCl(cod)}2] Complex in Organic Syntheses
Authors: Ishii Yasutaka , Sakaguchi Satoshi
Published: May 2004

We have found that the [{IrCl(cod)}2] complex catalyzes several reactions involving three-component couplings, hydrogen migration, vinyl ethers synthesis, and α-alkylation of ketones with alcohols, etc. Thus, the reaction of aldehydes, amines, and alkynes under the influence of a catalytic amount of [{IrCl(cod)}2] complex led to three-component coupling products through a new type of C–H bond activation adjacent to the nitrogen atom of imines. Aziridines were also synthesized by three-component couplings of aldehydes, amines, and ethyl diazoacetate in the presence of a catalytic amount of [{IrCl(cod)}2]. An innovation in the synthesis of vinyl ethers, which are very useful monomer materials in polymer syntheses but have been difficult to synthesize so far, was made by a simple exchange reaction of alcohols with vinyl acetates through a catalytic process using [{IrCl(cod)}2]. A unique α-alkylation of ketones with alcohols was successfully achieved under the influence of [{IrCl(cod)}2] and KOH without any solvents, leading to saturated ketones that elongated the carbon chain. Allyl homoallyl and diallyl ethers were converted by [{IrCl(cod)}2] into γ,δ-unsaturated aldehydes via a Claisen rearrangement of in situ-generated allyl vinyl ethers. These reactions provide a novel synthetic tool for important chemicals like vinyl ethers and ketones, which are practically synthesized in the chemical industry.
Study of ODE Reaction over Binary Rare Earth Oxyfluoride Sm2O3-LaF3 Catalysts
Authors: Luo J Z , Wan H L
Published: May 2004

The oxidative dehydrogenation of ethane (ODE) reaction has been investigated over Sm2O3-LaF3 and BaF2 promoted Sm2O3-LaF3 catalysts. Over Sm2O3-LaF3(molar ratio=1:1) and 16.7 mol% BaF2/Sm2O3-LaF3(molar ratio=1:1) high C2H4 selectivities of 89.7% and 83.9% were achieved respectively. XRD and XPS characterizations show the electron donating ability of the catalysts are stronger that corresponding rare earth oxide and fluoride. The addition of BaF2 can increase the number of the structure defects that may enhance the electron donating ability and increase the surface adsorbed oxygen concentration, thus should be favorable to improving the catalytic performance. However, the higher concentration of surface adsorbed oxygen is unfavorable for the ethene formation.
Molybdenum- and Tungsten-Catalyzed Allylation of Aromatic Compounds with Allylic Esters and Alcohols
Authors: Shimizu Isao , Sakamoto Toshiaki , Kawaragi Saeko , Maruyama Yooichiro , Yamamoto Akio
Published: May 2004

A novel method to substitute aromatic compounds with allylic groups using oxygen-containing allylic compounds in the presence of molybdenum or tungsten carbonyls under neutral conditions has been developed. The method is applicable to one step synthesis of methyl eugenol.
Modification of TiO2 Microporous Electrode with Quantum-Sized FeS2 Particles
Authors: Fang Jing Huai , Wu Jing Wen , Su Lian Yong , Zhang Xiang Yang , Lu Zu Hong
Published: May 2004

Ultrafine FeS2 particles were coated on a TiO2 electrode by low temperature chemical reaction of iron pentacarbonyl with sulfur in xylene. The coating extends both the optical absorption spectrum and the photocurrent action spectrum of TiO2 into visible region by sensitization mechanism. A blue shift observed in both the absorption and photocurrent action spectrum of the FeS2/TiO2 electrode is explained in terms of quantum size effect.
Cleavage Mode of Benzyltributylstannane Radical Cations Produced in Photoinduced Electron Transfer
Authors: Fukuzumi Shunichi , Yasui Kiyomi , Itoh Shinobu
Published: May 2004

Cleavage of metal-carbon bond of benzyltributylstannane radical cation produced in photoinduced electron transfer from benzyltributylstannane to 10-methylacridinium ion occurs to give benzyl radical rather than benzyl cation, resulting in formation of 9-benzyl-10-methyl-9,10-dihydroacridine selectively in dehydrated acetonitrile. In the presence of water, however, 10-methyl-9,10-dihydroacridine is also formed via electron transfer from benzyl radical to the dihydroacridine radical cation produced by protonation of acridinyl radical following the initial photoinduced electron transfer.
The Effect of Chromenone Receptors on the Selectivity of the Reaction between Pyrrolidine and 5-Hydroxymethyl-2-(5H)-furanone
Authors: Raposo César , Almaraz Marta , Martín Mercedes , Alcázar Victoria , Caballero Ma Cruz , Morán Joaquín R
Published: May 2004

Several chromenone-based receptors have been prepared. Despite the self-association of these hosts in CDCl3 they are able to bind hydroxymethylfuranones with a Kass of around 1000 M−1.

These compounds are able to accelerate the rate of the reaction of butenolide with pyrrolidine together with the increase of the selectivity.
Photochemical Behavior of Indane-1,2,3-trione in Degassed Alcoholic Solutions: Formation of 3-Substituted Phthalides
Authors: Tatsugi Jiro , Hara Tomoaki , Izawa Yasuji
Published: May 2004

Irradiation of indane-1,2,3-trione in degassed alcoholic solutions affords 3-alkoxycarbonylphthalides as the major product together with 3-alkoxyphthalides. 3-Alkoxycarbonylphthalides may be derived from the reaction between alcohols and the spirooxiranone intermediate, generated photochemically by cleavage of the bond between two carbonyl groups of indane-1,2,3-trione via a cyclobutenone biradical derivative.
Superior Dehydration of CH3OH over Double Layer Bed of Solid Acid Catalysts —A Novel Approach for Dimethyl Ether (DME) Synthesis
Authors: Roh Hyun-Seog , Jun Ki-Won , Kim Jae-Woo , Vishwanathan Venkataraman
Published: May 2004

A novel catalyst bed packed with two layers of γ-Al2O3 and Na-H-ZSM-5 showed an outstanding CH3OH dehydration activity, total selectivity to DME and longer stability during the reaction time. The TPD of NH3 confirmed that appropriate amounts of Na-impregnation on H-ZSM-5 drastically reduced the strong acid-sites resulting in 100% selectivity to DME.
First‐perspective alignment effects in a computer‐simulated environment
Authors: Wilson Paul N. , Wildbur Diane J.
Published: May 2004

In Experiment 1, participants explored two desktop, virtual environments (VEs), each comprising three city streets connected at right angles; for each participant one VE was open and one was enclosed. Following the first VE exploration, orientation estimates to remembered test locations were most accurate when participants imagined themselves aligned, rather than 90° misaligned or 180° or contra‐aligned, with the first part of the route. In the second VE, the effect was attenuated and the data pattern conformed to that anticipated from an orientation‐free memory. Experiment 2 followed the procedure of Experiment 1, but omitted the alignment tests after the first VE; following the second VE exploration, orientation estimates presented a similar pattern to those in first test of Experiment 1. These data are discussed in terms of cognitive load.
Tinker, Tailor, Soldier, Sailor: The Economies of Archaic Eleutherna, Crete
Authors: Perlman Paula
Published: May 2004

AbstractAs with other aspects of post-Minoan Crete studies there has been a tendency to accept a pan-Cretan economic model. A Dorian aristocracy, served by pre-Dorian serfs and their descendants, depended upon the produce of their private kleroi for membership in an andreion and citizen status. The elite preserved their political, social, and economic position by discouraging the development of a market economy on Crete in favor of a subsistence economy based upon agriculture, animal husbandry, and hunting. Discouraged were production of coinage, elite display, and manufacture for export (both within and beyond the island). Specialist craftsmen and other kinds of wage earners were either foreigners or members of a dependent population.
Selectivity and promiscuity in the interaction network mediated by protein recognition modules
Authors: Castagnoli Luisa , Costantini Anna , Dall'Armi Claudia , Gonfloni Stefania , Montecchi-Palazzi Luisa , Panni Simona , Paoluzi Serena , Santonico Elena , Cesareni Gianni
Published: May 2004

A substantial fraction of protein interactions in the cell is mediated by families of protein modules binding to relatively short linear peptides. Many of these interactions have a high dissociation constant and are therefore suitable for supporting the formation of dynamic complexes that are assembled and disassembled during signal transduction. Extensive work in the past decade has shown that, although member domains within a family have some degree of intrinsic peptide recognition specificity, the derived interaction networks display substantial promiscuity. We review here recent advances in the methods for deriving the portion of the protein network mediated by these domain families and discuss how specific biological outputs could emerge in vivo despite the observed promiscuity in peptide recognition in vitro.
Activation of big MAP kinase 1 (BMK1/ERK5) inhibits cardiac injury after myocardial ischemia and reperfusion
Authors: Cameron Scott J. , Itoh Seigo , Baines Christopher P. , Zhang Changxi , Ohta Shinsuke , Che Wenyi , Glassman Michael , Lee Jiing-Dwan , Yan Chen , Yang Jay , Abe Jun-ichi
Published: May 2004

Big MAP kinase 1 (BMK1/ERK5) plays a critical role in pre‐natal development of the cardiovascular system and post‐natal eccentric hypertrophy of the heart. Of the two isoforms upstream of MAPK‐kinase 5 (MEK5) known to exist, only the longer MEK5α isoform potently activates BMK1. We generated cardiac‐specific constitutively active form of the MEK5α (CA‐MEK5α transgenic (Tg) mice), and observed a 3 to 4‐fold increase in endogenous BMK1 activation and hyperphosphorylation of connexin 43 in the ventricles of the Tg compared to wild‐type mice. The CA‐MEK5α‐Tg‐mice demonstrated a profoundly accelerated recovery of left ventricular developed pressure after ischemia/reperfusion. We propose a novel role for BMK1 in protecting the heart from ischemia/reperfusion‐induced cardiac injury.
Progesterone receptor gene inactivation and CpG island hypermethylation in human leukemia cancer cells
Authors: Liu Ze-Jun , Zhang Xiao-Bing , Zhang Yun , Yang Xin
Published: May 2004

Previous studies showed that progesterone receptor (PR), one of the hormone receptor superfamily, was only connected with the sex‐correlated cancers such as breast cancer, endometrial cancer, prostate cancer, etc. This article deals with the PR gene in leukemia. We investigated the methylation status and the expression of the two different PR isoforms, PRA and PRB, in three leukemia cancer cell lines using methylation‐specific polymerase chain reaction (MSP‐PCR) and reverse transcription‐PCR. The correlation of PR methylation and expression together with DNA methyltransferase (DNMT1) was further studied. We found that DNMT1 is required to maintain CpG methylation and aberrant gene silencing of PR gene in human leukemia cancer cells. The activity of 5‐aza‐2′‐deoxycytidine in demethylation and gene reactivation may be through depleting cellular DNMT1 levels. In addition, extensive methylation of PRA and PRB was also observed in leukemia samples. Our results suggest that PR CpG island aberrant hypermethylation could be one molecular and genetic alteration in leukemia.
Oxidation of thioredoxin reductase in HeLa cells stimulated with tumor necrosis factor‐α
Authors: Kim Jae-Ryong , Lee Seon-Min , Cho Seung-Hyun , Kim Jung-Hyun , Kim Byung-Hak , Kwon Jaeyul , Choi Cheol Yong , Kim Yeong-Dae , Lee Seung-Rock
Published: May 2004

Stimulation of cells with tumor necrosis factor‐α (TNF‐α) results in the increase in generation of H2O2 in mitochondria that leads to apoptosis. The effect of H2O2 produced by TNF‐α on the redox status of selenocysteine (SeCys) residue essential for mitochondrial thioredoxin reductase (TrxR2) was investigated in HeLa cells. TNF‐α caused accumulation of oxidized TrxR2 with a thioselenide bond. The conditional induction of SeCys‐deficient TrxR2 resulted in the increased production of H2O2 and apoptosis. These results suggest that the SeCys residue of TrxR2 plays a critical role in cell survival by serving as an electron donor for Trx‐II and subsequent peroxiredoxin‐III, which is a primary line of defense against H2O2 in mitochondria.
Molecular cloning and characterization of a glucosyltransferase catalyzing glucosylation of curcumin in cultured Catharanthus roseus cells
Authors: Kaminaga Yasuhisa , Sahin F.Pinar , Mizukami Hajime
Published: May 2004

Catharanthus roseus cell suspension cultures are capable of converting exogenously supplied curcumin to various glucosides. The glucosylation efficiency is enhanced by addition of methyl jasmonate (MJ) to the cultures prior to curcumin administration. Two cDNAs encoding UDP‐glucosyltransferases (CaUGT1 and CaUGT2) were isolated from a cDNA library of cultured C. roseus cells, using a PCR method directed at the conserved UDP‐binding domain of plant glycosyltransferases. The sequence identity between their deduced amino acid sequences was 27%. The expression of both genes was up‐regulated by addition of MJ to the cell cultures although the mRNA level of CaUGT1 was much lower than that of CaUGT2. The corresponding cDNAs were expressed in Escherichia coli as fusion proteins with maltose‐binding protein. The recombinant CaUGT1 exhibited no glucosylation activity with either curcumin or curcumin monoglucoside as substrate, whereas the recombinant CaUGT2 catalyzed the formation of curcumin monoglucoside from curcumin and also conversion of curcumin monoglucoside to curcumin diglucoside. The use of the recombinant CaUGT2 may provide a useful new route for the production of curcumin glucosides.
Alternatives to telomerase: keeping linear chromosomes via telomeric circles
Authors: Tomaska Lubomir , McEachern Michael J. , Nosek Jozef
Published: May 2004

Recombination is often capable of lengthening telomeres in situations where telomerase is absent. This recombinational telomere maintenance is often accompanied by telomeric instability including the accumulation of extrachromosomal telomeric circles (t‐circles). Recent results of in vivo and in vitro experiments have suggested that t‐circles can lead to the production of extended stretches of telomeric DNA by serving as templates for rolling‐circle synthesis. This implies that t‐circles can provide an efficient means of telomere elongation. The existence of t‐circles in both nuclear and mitochondrial compartments of distantly related species suggests that they may be important contributors to an evolutionary conserved telomerase‐independent mechanism of maintenance of telomeric tandem arrays.
Participation of endoplasmic reticulum and mitochondrial calcium handling in apoptosis: more than just neighborhood?
Authors: Szabadkai György , Rizzuto Rosario
Published: May 2004

Over the past few years, extensive progress has been made in elucidating the role of calcium in the signaling of apoptosis. This has led to the characterization of calcium's role in the induction of apoptosis and in the regulation of effector proteases. In this review, we attempt to summarize the current knowledge regarding a segment of these studies, the interaction between the endoplasmic reticulum (ER) and mitochondria. This interface has been shown to play a crucial role in transferring agonist induced Ca2+signals to mitochondria during physiological processes. Recent evidence, however, extended the role of this Ca2+transfer to apoptotic pathways, showing that modulation of mitochondrial Ca2+uptake from the ER side has a prominent role in modulating cellular fate.
Inhibition of motility and invasiveness of renal cell carcinoma induced by short interfering RNA transfection of β1,4GalNAc transferase
Authors: Aoki Hiroshi , Satoh Makoto , Mitsuzuka Koji , Ito Akihiro , Saito Seiichi , Funato Tadao , Endoh Mareyuki , Takahashi Toshiko , Arai Yoichi
Published: May 2004

Human renal cell carcinoma (RCC) has been characterized by remarkable changes in ganglioside composition. TOS1 cells, typical of metastatic RCC, are characterized by predominance of GM2 as monosialoganglioside, and β1,4GalNAc disialyl‐Lc4 (RM2 antigen) as disialoganglioside [J. Biol. Chem. 276 (2001) 16695]. In order to observe the functional role of gangliosides in RCC malignancy, TOS1 cells were transfected with short interfering RNA (siRNA) based on open reading frame sequence of β1,4GalNAc transferase (β1,4GalNAc‐T), and its disordered sequence of siRNA (dsiRNA) as control. In siRNA transfectant, β1,4GalNAc‐T mRNA level and GM2 expression were greatly reduced, whereby GM3 expression appeared. In contrast, RM2 antigen level was unchanged, even though it has the same β1,4GalNAc epitope at the terminus. dsiRNA transfectant showed no change of β1,4GalNAc‐T mRNA and did not express GM3. Concomitant with reduction of GM2 and appearance of GM3, siRNA transfectant showed greatly reduced motility and invasiveness, although growth rate was unaltered. Both transfectants with siRNA and dsiRNA expressed the same level of tetraspanin CD9. Since CD9/GM3 complex is known to reduce integrin‐dependent motility and invasiveness [Biochemistry 40 (2001) 6414], it is plausible that motility and invasiveness of siRNA transfectant of TOS1 cells may be reduced by enhanced formation of such complex.
Exocytic pathway‐independent plasma membrane targeting of heterotrimeric G proteins
Authors: Takida Satoshi , Wedegaertner Philip B.
Published: May 2004

Heterotrimeric G proteins are lipid‐modified, peripheral membrane proteins that function at the inner surface of the plasma membrane (PM) to relay signals from cell‐surface receptors to downstream effectors. Cellular trafficking pathways that direct nascent G proteins to the PM are poorly defined. In this report, we test the proposal that G proteins utilize the classical exocytic pathway for PM targeting. PM localization of the G protein heterotrimers αsβ1γ2 and αqβ1γ2 occurred independently of treatment of cells with Brefeldin A, which disrupts the Golgi, or expression of Sar1 mutants, which prevent the formation of endoplasmic reticulum to Golgi transport vesicles. Moreover, the palmitoylation of αq was unaffected by Brefeldin A treatment, even though the palmitoylation of SNAP25 was blocked by Brefeldin A. Non‐palmitoylated mutants of αs and αq failed to stably bind to βγ and displayed a dispersed cytoplasmic localization when co‐expressed with βγ. These findings support a refined model of the PM trafficking pathway of G proteins, involving assembly of the heterotrimer at the endoplasmic reticulum and transport to the PM independently of the Golgi.
Activation of phospholipase D by osmotic cell swelling
Authors: Tomassen Sebastian F.B. , van der Wijk Thea , de Jonge Hugo R. , Tilly Ben C.
Published: May 2004

In response to osmotic cell swelling, Intestine 407 cells react with a rapid and transient activation of phospholipase D (PLD). To investigate the role of PLD during the regulatory volume decrease, cells were treated with 1‐butanol resulting in a depletion of PLD substrates. Activation of volume‐regulated anion channels, but not the cell swelling‐induced release of taurine, was largely inhibited in the presence of low concentrations of 1‐butanol. In addition, hypotonicity‐induced exocytosis, ATP release and subsequent endocytosis were found to be largely abrogated. The results support a model of cell volume regulation in which PLD plays an essential role in the cell swelling‐induced vesicle cycling and in the activation of volume‐sensitive anion channels.
The large subunit determines catalytic specificity of barley sucrose:fructan 6‐fructosyltransferase and fescue sucrose:sucrose 1‐fructosyltransferase
Authors: Altenbach Denise , Nüesch Eveline , Meyer Alain D. , Boller Thomas , Wiemken Andres
Published: May 2004

Plant fructosyltransferases are highly homologous in primary sequence and typically consist of two subunits but catalyze widely different reactions. Using functional expression in the yeast Pichia pastoris, we show that the substrate specificity of festuca sucrose:sucrose 1‐β‐d‐fructosyltransferase (1‐SST) and barley sucrose:fructan 6‐β‐d‐fructosyltransferase (6‐SFT) is entirely determined by the large subunit. Chimeric enzymes with the large subunit of festuca 1‐SST (LSuB) and the small subunit of barley 6‐SFT have the same catalytic specificity as the native festuca 1‐SST and vice versa. If the LSuB is expressed alone, it does not yield a functionally active enzyme, indicating that the small subunit is nevertheless essential.
Gestational treatment with cocaine and fluoxetine alters oxytocin receptor number and binding affinity in lactating rat dams
Authors: Johns Josephine M. , Lubin Deborah A. , Walker Cheryl H. , Joyner Paul , Middleton Christopher , Hofler Vivian , McMurray Matthew
Published: May 2004

Cocaine administered chronically throughout gestation has been correlated with deficits in maternal behavior, increased maternal aggressive behavior and decreased oxytocin levels in rats. In addition to its effects on oxytocin levels, cocaine is a potent serotonergic, dopaminergic and noradrenergic reuptake inhibitor. Alterations in the dopaminergic and serotonergic systems have been suggested as possibly having a role in cocaine‐induced maternal aggression. This study was in part, an attempt to understand some of the mechanisms by which cocaine increases postpartum aggression, particularly as they relate to changes in the oxytocin system.

Oxytocin receptor number and binding affinity in the medial preoptic area of the hypothalamus, ventral tegmental area, hippocampus and amygdala were determined for lactating rat dams on postpartum day 6 (PPD 6) that were gestationally treated with cocaine, fluoxetine, saline or an amfonelic acid/fluoxetine drug combination. Cocaine and fluoxetine treatment both resulted in a significant up‐regulation of oxytocin receptor number and lower receptor affinity in the amygdala of lactating rat dams compared to saline controls and the amfonelic acid/fluoxetine combination treatment group. Cocaine treatment also resulted in a significant down‐regulation of oxytocin receptors in the medial preoptic area and both cocaine and fluoxetine treated dams had the highest affinity for oxytocin receptors in this brain region. Results of the present study support previous data indicating that alterations in oxytocinergic and perhaps serotonergic system dynamics in the amygdala may play a role in cocaine‐induced postpartum aggression.
Growth factor pre‐treatment differentially regulates phosphoinositide turnover downstream of lysophospholipid receptor and metabotropic glutamate receptors in cultured rat cerebrocortical astrocytes
Authors: Rao Tadimeti S. , Lariosa‐Willingham Karen D. , Lin Fen‐Fen , Yu Naichen , Tham Chui‐Se , Chun Jerold , Webb Michael
Published: May 2004

Reactive gliosis is an aspect of neural plasticity and growth factor (GF) stimulation of astrocytes in vitro is widely regarded as a model system to study astrocyte plasticity. Astrocytes express receptors for several ligands including lysophosphatidic acid (LPA) and sphingosine‐1‐phosphate (S1P), agonists for the G‐protein‐coupled lysophospholipid receptors (lpRs). Activation of lpRs by LPA or S1P leads to multiple pharmacological effects including the influx of calcium, phosphoinositide (PI) hydrolysis, phosphorylation of extracellular receptor regulated kinase (ERK), release of arachidonic acid, and induces mitogenesis. Treatment of astrocytes in vitro with a growth factor cocktail (containing epidermal growth factor [EGF], basic fibroblast growth factor [bFGF] and insulin) led to a marked attenuation of lpR‐induced PI hydrolysis. In contrast, under identical conditions, GF treatment led to marked potentiation of PI hydrolysis downstream of activation of another abundantly expressed G‐protein coupled receptor, mGluR5. Quantitative gene expression analysis of GF‐treated or control astrocytes by TaqMan RT‐PCR indicated that GF treatment did not change gene expression of lpa1 and s1p1, but increased gene expression of s1p5 which is expressed at very low levels in basal conditions. These results suggest that GF differentially affected PLC activation downstream of mGluR5 versus lpR activation and that the changes in mRNA levels of lpRs do not account for marked attenuation of agonist‐induced phosphoinositide turnover.
Shoulder prostheses treating cuff tear arthropathy: A comparative biomechanical study
Authors: De Wilde L. F. , Audenaert E. A. , Berghs B. M.
Published: May 2004

Painful cuff tear arthropathy (CTA) affects the independence of the elderly. Surgical treatment often consists of joint replacement, the functional outcome of which remains variable. Knowledge of the biomechanical properties of the different prosthetic designs can guide the orthopaedic surgeon in the choice of implant to predict its clinical result. A 3‐D computer model of the glenohumeral joint is used to analyse the moment of the deltoid muscle in the scapular plane.

A geometrical 3‐D ball‐and‐socket model of the shoulder joint was used to calculate (1) the angle–force relationships, (2) the moment arm of the deltoid muscle and (3) the moment of the deltoid muscle components, for increasing degrees of arm elevation in the scapular plane. In this 3‐D model, a clinical thoraco‐scapular rhythm analysis was implemented, based on measurements in normal subjects, patients treated with an anatomical prosthesis and patients treated with an inversed delta III prosthesis®. These data were compared for 10 different prosthetic treatment options.

Results. Muscle angle–force curves show a favourable slope in non‐anatomical prosthetic designs, where the centre of rotation of the glenohumeral joint is medialized, the deltoid muscle is elongated and the humeral shaft is lateralized. On the contrary, anatomical prosthetic designs do not perform well in this computer analysis.

Conclusions. From a biomechanical point of view, a shoulder prosthesis which medializes the centre of rotation, lengthens the deltoid muscle and increases the deltoid lever arm, results in a significantly more powerful abduction of the shoulder, despite complete loss of rotator cuff function.

Relevance. This study explains why a successful functional outcome can be expected in CTA with a reversed prosthesis. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
Viable osteoblastic potential of cortical reamings from intramedullary nailing
Authors: Frölke Jan Paul M. , Nulend Jenneke Klein , Semeins Cor M. , Bakker Fred C. , Patka Peter , Haarman Henk J. Th. M.
Published: May 2004

To analyze the effect of intramedullary reaming on fracture healing, we investigated whether or not cortical reamings contain viable bone cells. There are several tissue components contained in medullary reamings including blood, bone marrow and cortical bone. This study is focused on the cortical reamings, which are produced during reaming of the medullary cavity. They may stimulate fracture healing but it is still unclear if they contain vital bone cells. We tested the hypothesis that these cortical reamings are a source of viable bone cells and compared cell cultures with cultivated cells from iliac crest biopsies. Responses of protein content and ALP activity to vitD stimulation in the cells were considered as properties of viability. Ten in tact living sheep femora were fully reamed and the cortical reamings were cultivated in a standard manner and compared with cultivated cells from ipsilateral iliac crest biopsies from the same animals. Cells started to grow from the reamings as well as the iliac crest within 2–5 days, and covered the entire culture flask within 9–13 days. Protein content and ALP activity in cells from both reamings and iliac crest were significantly responsive to vitD stimulation. Cortical reamings from intramedullary nailing have osteoblastic potential and contain living bone cells similar to bone cells from the iliac crest. These findings may further explain the superior healing of fractures, treated with reamed nailing. © 2004 Orthopaedic Research Society. Published y Elsevier Ltd. All rights reserved.
Effects of rotation on measurement of lower limb alignment for knee osteotomy
Authors: Kawakami Hideo , Sugano Nobuhiko , Yonenobu Kazuo , Yoshikawa Hideki , Ochi Takahiro , Hattori Asaki , Suzuki Naoki
Published: May 2004

The purposes of this study were to clarify the effects of rotation on two‐dimensional measurement of lower limb alignment for knee osteotomy using a three‐dimensional method and to determine whether this 3‐D simulation method could help with planning of knee osteotomy. We developed computer software to calculate femorotibial angle (FTA) and hip–knee–ankle angle (HKA) and simulate knee osteotomy from a CT‐based 3‐D bone model of the lower limb. Lower limb rotation on anteroposterior long‐standing radiographs was measured by superimposing the 3‐D bone models. Changes in alignment with limb rotation were calculated using the software. FTA after virtual closed‐wedged osteotomy was measured for a hypothetical case of a rotation error of the osteotomy plane in reattaching the proximal cutting surface to the distal cutting surface. For 31 varus knees in 20 patients with medial compartment arthritis, the mean rotation angle, relative to the epicondylar axis, with variable limb position was 7.4 ± 3.9° of internal rotation (mean ± SD), ranging from 8° of external rotation to 14° of internal rotation; the mean changes in FTA and HKA were 3.5 ± 2.2° (range, 0.4–8.6) and 1.6 ± 1.3° (range, 0.2–4.9), respectively. The FTA “flexion angle” (lateral view alignment from neutral AP) and the absolute HKA “flexion angle” correlated with the change in FTA and HKA with limb rotation, respectively (FTA, R = 0.999; HKA, R = 0.993). The mean change in FTA after virtual closed‐wedged osteotomy was 3.2° for internal and external 10° rotation errors in reattaching the osteotomy plane. Rotation may affect measurement of lower limb alignment for knee osteotomy, and 3‐D methods are preferable for surgical planning. © 2004 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.
9000 years of salmon fishing on the Columbia River, North America
Authors: Butler Virginia L , O'Connor Jim E
Published: May 2004

A large assemblage of salmon bones excavated 50 yr ago from an ∼10,000-yr-old archaeological site near The Dalles, Oregon, USA, has been the primary evidence that early native people along the Columbia River subsisted on salmon. Recent debate about the human role in creating the deposit prompted excavation of additional deposits and analysis of archaeologic, geologic, and hydrologic conditions at the site. Results indicate an anthropogenic source for most of the salmonid remains, which have associated radiocarbon dates indicating that the site was occupied as long ago as 9300 cal yr B.P. The abundance of salmon bone indicates that salmon was a major food item and suggests that migratory salmonids had well-established spawning populations in some parts of the Columbia Basin by 9300–8200 yr ago.
Women's Experiences of Unexpected Ultrasound Findings
Authors: Mitchell Lisa M.
Published: May 2004

Ultrasound imaging is an important screening and diagnostic tool in prenatal care, but for many couples in Canada and the United States, it is primarily a meaningful social ritual of seeing and meeting their baby. This article examines how women perceive ultrasound when they receive unexpected abnormal ultrasound findings. Drawing from qualitative analysis of semistructured interviews with 42 Canadian women, the article discusses women's reactions to receiving unexpected findings, and their perspectives on disclosure of results and on seeing the impaired fetus. Implications are discussed for practitioners regarding prescan counseling, informed choice, and disclosure of abnormal ultrasound findings.
Ethics in Nursing: The Caring Relationship, 3rd ed
Authors: Van Hoover Cheri , Thompson Joyce Beebe
Published: May 2004

By Verena Tschudin. Edinburgh: Butterworth Heinemann imprint of Elsevier Science Limited, 2003. 218 pages. Paperback.
Practice Guidelines for Obstetrics & Gynecology, 2nd ed
Authors: Van Hoover Cheri , Camune Barbara
Published: May 2004

By Geri Morgan and Carole Hamilton. Philadelphia: Lippincott, Williams & Wilkins, 2003. $42.95, softcover (spiral).
The Manner Born: Birth Rites in Cross‐Cultural Perspective
Authors: Van Hoover Cheri , Hunter Lauren P.
Published: May 2004

Edited by Lauren Dundes. Walnut Creek (CA): Altamira Press, 2003. 239 pages. $27.95, paperback, $75.00, hardback.