bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation and characteristics of a water‐soluble chitosan–heparin complex
Authors: Kweon Dong‐Keon , Lim Seung‐Taik
Published: January 2003

To improve the wound‐healing ability of chitosan, heparin, known to be effective in wound healing, was complexed with water‐soluble chitosan (WSC) by chemical reaction. The chemical structure of the water‐soluble chitosan–heparin (CH) complex was analyzed, and CH complex formation was confirmed with an FTIR spectrometer. The mechanical and thermal properties of the CH complex were measured by a tensile tester and thermal analyzers (DSC and TGA). Within the heparin content up to ≈470 IU/g in the aqueous CH complex solution, the intrinsic viscosity and tensile strength of the water‐soluble CH complex gradually increased, but thermal stability slightly decreased by introducing the heparin into the WSC. When the heparin content was greater than these values (470 IU/g), the water‐insoluble CH complex, which is supposed to have a multisubstituted or crosslinked structure, precipitated in the aqueous water‐soluble CH complex solution. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1784–1789, 2003
Synthesis of isopropenylbenzyl‐terminated macromonomers and preparation of polymer brushes by anionic homopolymerization
Authors: Ishizu Koji , Satoh Junichiro
Published: January 2003

Isopropenylbenzyl‐terminated polystyrene (PS) macromonomers were synthesized by anionic addition in a two‐stage process using styrene and 1,4‐diisopropenylbenzene (DIPB) in benzene. The reaction products of polystyryl anions with DIPB provided PS macromonomer possessing less than two isopropenylbenzyl groups at the propagating end under the condition of being in hydrocarbon solvent at 25°C (ceiling temperature) because of the anionic equilibrium nature. Subsequently, anionic homopolymerization of such macromonomers was carried out in tetrahydrofuran (THF) at −78°C using anionic initiators to prepare the polymer brushes. The conversion of polymer brushes was very low (ca. 5%). Moreover, the degree of polymerization (DP) was less than 50. The low concentration of propagating chain ends seemed to affect the formation of polymer brushes. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87:1790–1793,2003
Influence of polyvinylpyrrolidone on the hydrophobic properties of partially porous poly(styrene–divinylbenzene) particles for biological applications
Authors: Kao Chen‐Yu , Lo Tzu‐Chiang , Lee Wen‐Chien
Published: January 2003

For the preparation of polymer particles by free radical, stabilizers are usually present in the reaction mixture to maintain the separation of particles from each other. Polyvinylpyrrolidone (PVP) is one the hydrophilic polymers that has been extensively used as the stabilizer in the polymerization system employing a polar solvent or solvent mixture as the continuous phase. As shown in the present study, the presence of PVP in the later steps could significantly influence the hydrophobic property of partially porous poly(styrene–divinylbenzene) (PS–DVB) particles, prepared by the method of multistep swelling and polymerization involving the use of polymeric porogens. The association of PVP molecules on the particle surface reduced the hydrophobicity and consequently the capability of particles for biological applications. For the reversed‐phase liquid chromatography of penicillin G and its enzymatic hydrolysis product, particles prepared without PVP led to an enhancement in both retention and resolution, compared with particles resulting from the use of PVP. Results from lipase immobilization on these particles also showed that the presence of PVP could shield the hydrophobic groups on the particle surface and then reduce the efficiency of enzyme immobilization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1818–1824, 2003
Preparation of liquefied bark‐based resol resin and its application to particle board
Authors: Lee Wen‐Jau , Liu Cheng‐Tzu
Published: January 2003

Barks of Taiwan acacia (Acacia confusa) and China fir (Cunninghamia lanceolata) were liquefied in the presence of phenol with sulfuric acid (H2SO4) and hydrochloric acid (HCl) as catalyst. The properties of resins prepared from liquefied bark and the feasibility of liquefied bark‐based resol resins in particle board manufacturing were investigated. The viscosity and thermosetting property of liquefied bark‐based resol resins were affected by the kind of bark species and the catalyst used. Liquefied bark‐based resol resins using China fir bark as raw material had higher viscosity than the ones using Taiwan acacia bark. In the course of thermosetting, liquefied bark‐based resol resins using Taiwan acacia bark as raw material had a higher maximum temperature of exothermic peak and onset temperature as well as a larger quantity of exothermic heat than those using China fir bark. Resol resins prepared from bark liquefied with H2SO4 as catalyst had higher viscosity, while resins with HCl as catalyst had a higher maximum temperature and height of exothermic peak and a larger quantity of exothermic heat at thermosetting. Particle board made with A‐S adhesive that was prepared from liquefied Taiwan acacia bark with H2SO4 as catalyst had the best particle board properties than those made with other adhesives. For the particle board made with A‐S adhesive, its static bending strength and internal bonding strength would be increased as the hot‐pressing time extended. The particle board made with hot‐pressing temperature of 150°C and hot‐pressing time of 10 min had the maximum normal and wet static bending strength and internal bonding strength. Its normal static bending strength was 170.8 kgf/cm2 and the particle board showed satisfactory wet static bending strength and internal bonding strength. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1837–1841, 2003
Enhancement of in vitro and in vivo microdialysis recovery of SB‐265123 using Intralipid® and Encapsin® as perfusates
Authors: Ward Keith W. , Medina Sarah J. , Portelli Samm T. , Mahar Doan Kelly M. , Spengler Michael D. , Ben Michael M. , Lundberg David , Levy Mark A. , Chen Emile P.
Published: January 2003

This study was conducted to compare the ability of two potential microdialysis perfusates to enhance the recovery of SB‐265123, a lipophilic, highly protein‐bound compound, both in vitro and in vivo. Initial in vitro experiments established that the recovery of SB‐265123 by microdialysis using normal saline as a perfusate was poor (1.7%). Different concentrations of Intralipid® and Encapsin® also were evaluated in an identical in vitro setting, to determine enhancement of recovery. In vitro recovery was enhanced to approximately 24 and 65% with 5 and 20% Intralipid®, and to approximately 59 and 62% with 5 and 20% Encapsin®, respectively. A rat in vivo study was conducted with 20% Encapsin® to confirm the in vitro observations. In the in vivo study, 75–80% recovery of free SB‐265123 was achieved using 20% Encapsin® as a perfusate. The results from this study indicate that for SB‐265123, a lipophilic, highly protein‐bound molecule, Encapsin® is an efficient recovery enhancer in vitro. The results from this investigation further demonstrate that a recovery enhancer may be useful for in vivo applications, even with a compound that is highly bound to plasma protein. Copyright © 2002 John Wiley & Sons, Ltd.
Pharmacokinetics and pharmacodynamics of intravenous trasemide in mutant nagase aalbuminemic rats
Authors: Kim Eun J. , Lee Myung G.
Published: January 2003

The importance of plasma protein binding of intravenous furosemide in circulating blood for its urinary excretion and hence its diuretic effects in mutant Nagase analbuminemic rats (NARs, an animal model for human familial analbuminemia) was reported. Based on the furosemide report, the diuretic effects of another loop diuretic, torasemide, could be expected in NARs if plasma protein binding of torasemide is considerable in the rats. This was proven by this study. After intravenous administration of torasemide, 10 mg/kg, to NARs, the plasma protein binding of torasemide was 23.3% in the rats due to binding to α‐ and β‐globulins (this value, 23.3%, was greater than only 12% for furosemide), and hence the percentages of intravenous dose of torasemide excreted in 8‐h urine as unchanged drug was 14.9% in the rat (this value was considerably greater than only 7% for furosemide). After intravenous administration of torasemide to NARs, the AUC (301 versus 2680 µg/min/ml) was significantly smaller [due to significantly faster both Clr (4.81 versus 0.386 ml/min/kg) and Clnr (28.3 versus 3.33 ml/min/kg)], terminal half‐life (18.3 versus 73.5 min) and mean residence time (6.97 versus 61.8 min) were significantly shorter (due to faster Cl, 33.2 versus 3.74 ml/min/kg), and amount of 8‐h urinary excretion of unchanged torasemide (446 versus 323 µg, due to increase in intrinsic renal excretion) was significantly greater than those in control rats. The 8‐h urine output and 8‐h urinary excretions of sodium and chloride were comparable between two groups of rats although the 8‐h urinary excretion of torasemide was significantly greater in NARs. This could be explained by the following. The amount of urinary excretion of torasemide was significantly greater in NARs than that in control rats only between 0 and 30 min urine collection. In both groups of rats, the urinary excretion rate of torasemide during 0–30 min reached an upper plateau with respect to urine flow rate as well urinary excretion rates of sodium and chloride. Therefore, the diuretic effects (8‐h urine output and 8‐h urinary excretions of sodium and chloride) were not significantly different between the two groups of rats. Copyright © 2002 John Wiley & Sons, Ltd.
Solid‐phase micro‐extraction—comprehensive two‐dimensional gas chromatography of ginger (Zingiber officinale) volatiles
Authors: Shao Yajing , Marriott Philip , Shellie Robert , Hügel Helmut
Published: January 2003

Ginger (Zingiber officinale) headspace has been studied by using solid‐phase microextraction (SPME), combined with comprehensive two‐dimensional (2D) gas chromatography (GC × GC). A 100 µm PDMS fibre proved to be the most useful in the present study. SPME–GC–MS analysis was also performed to identify the components extracted from the volatile fraction. The ease of SPME makes it a useful tool for qualitative comparison of samples, and here fresh ginger was contrasted with a crystallized ginger sweet. The latter sample had fewer of the more volatile components, but the heavier components appeared to compare well in the two samples. The use of SPME as a sample introduction method for GC × GC was investigated, using the two different ginger samples. The correspondence of retention times in the 2D separation space was found to be excellent, and should allow reliable identification of the compounds if adequate standards or comparative retentions of known components are available. Copyright © 2002 John Wiley & Sons, Ltd.
Essential oil composition of Acorus calamus L. from the lower region of the Himalayas
Authors: Raina V. K. , Srivastava S. K. , Syamasunder K. V.
Published: January 2003

The rhizomes and leaf oils of Acorus calamus L. were analysed by GC and GC–MS; 29 and 30 constituents were identified from the rhizome and leaf oils, respectively, comprising 99.7% of each of the oils β‐Asarone (83.2%) and α‐asarone (9.7%) were the major constituents in the rhizome oil, while β‐asarone (85.6%) and linalool (4.7%) were the major constituents in the leaf oil. Copyright © 2002 John Wiley & Sons, Ltd.
Production of rose absolute from rose concrete
Authors: Aydinli Meltem , Tutaş Mehmet
Published: January 2003

Rose absolute was produced from rose concrete at two temperatures (−25°C, −20°C) using two concentrations (96%, 80%) of ethanol as solvent. Chemical composition of the absolute was determined by GC and GC–MS and then some properties of it such as refractive index and density were examined. It was found that the absolute mainly consists of phenylethyl alcohol, citronellol, geraniol, nerol, 1‐nonadecene, methyl eugenol, eugenol, nonadecane, benzyl alcohol. The amounts of these compounds were found to depend largely upon the conditions of production of absolute and the concentration of the ethanol used. The yields of absolute were found to be in the range of 58–64%. Copyright © 2002 John Wiley & Sons, Ltd.
Composition of the steam volatiles of six Euphorbia spp. from Greece
Authors: Fokialakis N. , Melliou E. , Magiatis P. , Harvala C. , Mitaku S.
Published: January 2003

The chemical composition of the steam volatiles obtained from the inflorescences of six Euphorbia spp., E. acanthothamnos, E. apios, E. characias, E. dendroides, E. helioscopia and E. rigida, were analysed by GC and GC‐MS. Sixty‐nine components, representing 82–94% of the total composition for the six oils, were identified. The major components were found to be nonanal, germacrene, phytol, β‐caryophyllene, heneicosane and heptacosane. Copyright © 2002 John Wiley & Sons, Ltd.
Composition of the essential oil of Cotinus coggygria Scop. from Turkey
Authors: Demirci B. , Demirci F. , Başer K. H. C.
Published: January 2003

The oil from leaves of Cotinus coggygria Scop. (Anacardiaceae) obtained by hydrodistillation was analysed by GC–MS. Forty‐two components were characterized, representing 99.6% of the total components detected. The major constituents were identified as limonene (48.5%), (Z)‐β‐ocimene (27.9%) and (E)‐β‐ocimene (9.7%). Copyright © 2002 John Wiley & Sons, Ltd.
Acorenone in the essential oil of flowering aerial parts of Seseli tortuosum L.
Authors: Bader Ammar , Caponi Chiara , Cioni Pier Luigi , Flamini Guido , Morelli Ivano
Published: January 2003

The essential oil composition of a population of Seseli tortuosum, collected on the coasts of Marina di Vecchiano (Pisa) Italy, was studied for the first time. The essence, obtained from leaves and flowering tops of the plant, was characterized mainly by the presence of myrcene (29.2%), α‐pinene (18.6%), β‐pinene (13.2%) and limonene (10.6%). Among sesquiterpenes, only acorenone is quantitatively represented (6.3%). This is a rare sesquiterpene, isolated for the first time in Acorus calamus, quite uncommon in essential oils. Copyright © 2002 John Wiley & Sons, Ltd.
Components of Turnera diffusa Willd. var. afrodisiaca (Ward) Urb. Essential Oil
Authors: Bicchi Carlo , Rubiolo Patrizia , Saranz Camargo Ely Eduardo , Vilegas Wagner , de Souza Gracioso Juliano , Monteiro Souza Brito Alba Regina
Published: January 2003

Turnera diffusa Willd. var. afrodisiaca (Ward) Urb. (syn. T. aphrodisiaca) (Turneraceae) is a common aromatic plant growing wild in the subtropical regions of America and Africa. Its essential oil was studied by GC and GC–MS. Fifty‐four components were characterized and identified, the most abundant being 1,8‐cineol (11.4%), opoplenone (10.3%) cadalene (5.1%) and epi‐cubenol (4.1%). Copyright © 2002 John Wiley & Sons, Ltd.
Studies on essential oils. Part 35: chemical and biocidal investigations on Tagetes erecta leaf volatile oil
Authors: Singh Gurdip , Singh Om Prakash , De Lampasona M. P. , Catalán César A. N.
Published: January 2003

Chemical investigations on the leaf essential oil of Tagetes erecta, performed by HPLC, GC and GC–MS techniques, showed the presence of 26 components, accounting for 89% of the total oil. The major constituents were (Z)‐β‐ocimene (42.2%), dihydrotagetone (14.3%), (Z)‐tagetone (8.3%), limonene (7.3%), (E)‐ocimenone (6.1%) and (Z)‐ocimenone (5.3%). The biocidal investigations showed that the oil possessed a significant but limited and dose‐related antifungal and insecticidal activity. The oil showed 100% mortality of white termite (Odontotermes obesus Rhamb.) at a dose of 6 µl/Petri‐plate after 24 h of exposure, while at lower doses and shorter exposures it showed diminished mortality rates. The oil only partially affected the mycelial growth of any of the tested fungi. Thus, the leaf oil of this plant, which is rich in (Z)‐β‐ocimene, has a statistically significant antifungal and insecticidal activity. Copyright © 2002 John Wiley & Sons, Ltd.
Analyses of orange spirit flavour by direct‐injection gas chromatography–mass spectrometry and headspace solid‐phase microextraction/GC–MC
Authors: Da Porto Carla , Pizzale Lorena , Bravin Michela , Conte Lanfranco S.
Published: January 2003

Orange spirit, a novel fruit distillate, was analysed by direct injection gas chromatography–mass spectrometry and headspace solid‐phase microextraction (SPME) coupled to GC–MS. Different commercial SPME fibre types have been tested for the analysis of orange spirit. The divinylbenzene/carboxen on poly(dimethylsiloxane) fibre was chosen because it gave the best repeatability of the method. Headspace SPME–GC–MS selectivity was found to be comparable to GC direct injection for most orange spirit volatile compounds. The divinylbenzene/carboxen/poly(dimethylsiloxane) fibre had very high affinity for non‐polar and less polar compounds, especially for some components of orange peel oil, which could be considered the impact compounds of orange spirit. In this way, good sensitiveness was ensured for these compounds. Conversely, the GC analysis was more sensitive for polar compounds, especially for molecules such as methanol, isobutanol, n‐butanol and iso‐amyl alcohols. SPME was a useful tool for quickly screening orange flavour compounds and can be considered as complementary to GC direct injection analysis, which should be used when an accurate quantitative determination of analytes is required. Copyright © 2002 John Wiley & Sons, Ltd.
A new second‐moment closure approach for turbulent swirling confined flows
Authors: Lu Pisi , Semião Viriato
Published: January 2003

An improved anisotropic model for the dissipation rate—ε—of the turbulent kinetic energy (k), to be used together with a non‐linear pressure‐strain correlations model, is proposed. Experimental data from the open literature for two confined turbulent swirling flows are used to assess the performance of the proposed model in comparison to the standard ε transport equation and to a linear approach to model the pressure‐strain term that appears in the exact equations for the Reynolds‐stress tensor. For the less strongly swirling flow the predictions show much more sensitivity to the εtransport equation than to the pressure‐strain model. In opposition, for the more strongly swirling flow, the results show that the predictions are much sensitive to the pressure‐strain model. Nevertheless, the improved εtransport equation together with the non‐linear pressure strain model yield predictions in good agreement with experiments in both studied cases. Copyright © 2003 John Wiley & Sons, Ltd.
Dynamic analysis of baffled fuel‐storage tanks using the ALE finite element method
Authors: Cho J. R. , Lee S. Y.
Published: January 2003

This paper is concerned with the parametric investigation on the structural dynamic response of moving fuel‐storage tanks with baffles. Since the structural dynamic behaviour is strongly coupled with interior liquid motion, the design of a fuel‐storage tank securing the structural stability becomes the appropriate suppression of the flow motion, which is in turn related to the baffle design. In order to numerically investigate the parametric dynamic characteristics of moving tanks, we employ the arbitrary Lagrangian–Eulerian (ALE) finite element method that is widely being used to deal with the problems with free surface, moving boundary, large deformation and interface contact. Following the theoretical and numerical formulations of fluid‐structure interaction problems, we present parametric numerical results of a cylindrical fuel‐storage tank moving with uniform vertical acceleration, with respect to the baffle number and location, and the inner‐hole diameter. Copyright © 2003 John Wiley & Sons, Ltd.
Approximate simulation of stratospheric flow from aircraft data
Authors: Humi Mayer
Published: January 2003

We show how stratospheric data collected by an aircraft along its flight path can be used to initialize steady state approximate simulations of the stratospheric flow. To this end we reformulate the initial value problem for Boussinesq equations as a large system of stiff ordinary differential equations (using the method of lines). Initial conditions for this system are derived from the aircraft data. As a result we are able to compute the Brunt–Vaisala frequency, Richardson number and the vorticity in the vicinity of the flight path. Copyright © 2003 John Wiley & Sons, Ltd.
The entorhinal cortex of the mouse: Organization of the projection to the hippocampal formation
Authors: van Groen Thomas , Miettinen Pasi , Kadish Inga
Published: January 2003

The origin and the terminations of the projections from the entorhinal cortex to the hippocampal formation of the mouse (C57BL/6J strain) have been studied using anterogradely and retrogradely transported tracers. The entorhinal cortex is principally divided into two areas, the lateral entorhinal area (LEA) and the medial entorhinal area (MEA). LEA is the origin of the lateral perforant path that terminates in the outer one‐third of the molecular layer of the dentate gyrus, and MEA is the origin of the medial perforant path that ends in the middle one‐third of the molecular layer of the dentate gyrus. This projection is mostly to the ispsilateral dentate gyrus; only a few labeled axons and terminals are found in the contralateral dentate gyrus. The projection to the dentate gyrus originates predominantly from neurons in layer II of the entorhinal cortex. The entorhinal cortex also projects to CA3 and CA1 and to subiculum; in both CA3 and CA1, the terminals are present in stratum lacunosum‐moleculare, whereas in the subiculum the terminals are in the outer part of the molecular layer. The projection from the entorhinal cortex to CA3, CA1, and subiculum is bilateral, and it originates predominantly from neurons in layer III, but a small number of neurons in the deeper layers of the entorhinal cortex contributes to this projection. The projection of entorhinal cortex to the hippocampus is topographically organized, neurons in the lateral part of both LEA and MEA project to the dorsal part (i.e., septal pole) of the hippocampus, whereas the projection to the ventral (i.e., temporal pole) hippocampus originates from neurons in medial parts of the entorhinal cortex. Hippocampus 2003;13:133–149. © 2003 Wiley‐Liss, Inc.
Distribution and morphology of serotonin‐immunoreactive axons in the hippocampal region of the New Zealand white rabbit. I. Area dentata and hippocampus
Authors: Bjarkam Carsten R. , Sørensen Jens Christian , Geneser Finn A.
Published: January 2003

This study provides a detailed light microscopic description of the morphology and distribution of immunohistochemically stained serotonergic axons in the hippocampal region of the New Zealand white rabbit. The serotonergic axons were segregated morphologically into three types: beaded fibers, fine fibers, and stem‐axons, respectively. Beaded fibers were thin serotonergic axons with large varicosities, whereas thin axons with small fusiform or granular varicosities were called fine fibers. Finally, thick straight non‐varicose axons were called stem‐axons. Beaded fibers often formed large conglomerates with numerous boutons (pericellular arrays) in close apposition to the cell‐rich layers in the hippocampal region, e.g., the granular and hilar cell layers of the dentate area and the pyramidal cell layer ventrally in CA3. The pericellular arrays in these layers were often encountered in relation to small calbindin‐D28K‐positive cells, as shown by immunohistochemical double staining for serotonin and calbindin‐D28K. The beaded and fine serotonergic fibers displayed a specific innervation pattern in the hippocampal region and were encountered predominantly within the terminal field of the perforant path, e.g., the stratum moleculare hippocampi and the outer two‐thirds of the dentate molecular layer. These fibers were also frequently seen in the deep part of the stratum oriens and the alveus, forming a dense plexus in relation to large multipolar calbindin‐D28K‐positive cells and their basal extensions. Stem‐axons were primarily seen in the fimbria and alveus. This innervation pattern was present throughout the entire hippocampal formation, but there were considerable septotemporal differences in the density of the serotonergic innervation. A high density of innervation prevailed in the ventral/temporal part of the hippocampal formation, whereas the dorsal/septal part received only a moderate to weak serotonergic innervation. These results suggest that the serotonergic system could modulate the internal hippocampal circuitry by way of its innervation in the terminal field of the perforant path, the hilus fasciae dentatae, and ventrally in the zone closely apposed to the mossy fiber layer and the pyramidal cells of CA3. This modulation could be of a dual nature, mediated directly by single serotonergic fibers traversing the hippocampal layers or indirectly by the pericellular arrays and their close relation to the calbindin‐D28K‐positive cells. The marked septotemporal differences in innervation density point toward a difference between the ventral and dorsal parts of the hippocampal formation with respect to serotonergic function and need for serotonergic modulation. Hippocampus 2003;13:21–37. © 2003 Wiley‐Liss, Inc.
Encoding of novel picture pairs activates the perirhinal cortex: An fMRI study
Authors: Pihlajamäki Maija , Tanila Heikki , Hänninen Tuomo , Könönen Mervi , Mikkonen Mia , Jalkanen Ville , Partanen Kaarina , Aronen Hannu J. , Soininen Hilkka
Published: January 2003

It is well established in nonhuman primates that the medial temporal lobe (MTL) structures, the hippocampus and the entorhinal and perirhinal cortices, are necessary for declarative memory encoding. In humans, the neuropathological and neuropsychological changes in early Alzheimer's disease (AD) further support a role for the rhinal cortex in the consolidation of new events into long‐term memory. Little is known, however, regarding the function of the rhinal cortex in humans in vivo. To examine the participation of the interconnected MTL structures as well as the whole‐brain network of activated brain areas in visual associative long‐term memory, functional magnetic resonance imaging (fMRI) was used to determine the brain regions that are activated during encoding and retrieval of paired pictures in 12 young control subjects. The most striking finding in the MTL activation pattern was the consistent activation of the perirhinal cortex in the encoding‐baseline and encoding‐retrieval comparisons with a strict statistical threshold (P < 0.00001). In contrast, no perirhinal cortex activation was detected in the retrieval‐baseline or retrieval‐encoding comparisons even with a low statistical threshold (P < 0.05). The location of the perirhinal activation area was in the transentorhinal part of the perirhinal cortex, in the medial bank of the collateral sulcus. The hippocampus and the more posterior parahippocampal gyrus were activated in both encoding and retrieval conditions. During the encoding processing, MTL activations were more consistent and the hippocampal activation area located more anteriorly than during retrieval. The frontal, parietal, temporal, and occipital association cortices were also activated in the encoding‐baseline and retrieval‐baseline comparisons. The data suggest that encoding, but not retrieval, of novel picture pairs activates the perirhinal cortex. To our knowledge, this is the first fMRI study reporting encoding activation in this transentorhinal part of the perirhinal cortex, the site of the very earliest neuropathological changes in AD. Hippocampus 2003;13:67–80. © 2003 Wiley‐Liss, Inc.
Selective impairment of fornix‐transected rats on a new nonspatial, odor‐guided task
Authors: Hudon C. , Doré F.Y. , Goulet S.
Published: January 2003

In the present experiment, sham‐operated (SH) and fornix‐transected (FX) rats were trained on a new nonspatial, odor‐guided task. On each session, eight odor pairs were presented twice. On the first occurrence of a pair, rats were reinforced for pushing the container (go response) in which the olfactory stimuli were placed. On the second occurrence, they were not reinforced and had to refrain from responding (no‐go response) to be scored as success. Rats were first trained to criterion on odor pairs made of replicates of the same odor (S pairs). Then they were trained to criterion on pairs made of different odors, each member of the pair overlapping with that of another pair (O pairs) and finally, on pairs of different odors with no overlap (NO pairs). The results showed that the number of sessions to reach criterion was significantly higher in FX than in SH rats during training on O pairs, but not during training on S or on NO pairs. These findings are consistent with the configural (Rudy and Sutherland, 1995: Hippocampus 5:375–389) or relational (Eichenbaum et al., 1994: Behav Brain Sci 17:449–518) account of the hippocampal memory function. Hippocampus 2003;13:48–52. © 2003 Wiley‐Liss, Inc.
Regional analysis of hippocampal activation during memory encoding and retrieval: fMRI study
Authors: Greicius Michael D. , Krasnow Ben , Boyett‐Anderson Jesse M. , Eliez Stephan , Schatzberg Alan F. , Reiss Allan L. , Menon Vinod
Published: January 2003

Investigators have recently begun to examine the differential role of subregions of the hippocampus in episodic memory. Two distinct models have gained prominence in the field. One model, outlined by Moser and Moser (Hippocampus 1998;8:608–619), based mainly on animal studies, has proposed that episodic memory is subserved by the posterior two‐thirds of the hippocampus alone. A second model, derived by Lepage et al. (Hippocampus 1998;8:313–322) from their review of 52 PET studies, has suggested that the anterior hippocampus is activated by memory encoding while the posterior hippocampus is activated by memory retrieval. Functional magnetic resonance imaging (fMRI) studies have tended to show limited activation in the anteriormost regions of the hippocampus, providing support for the Moser and Moser model. A potential confounding factor in these fMRI studies, however, is that susceptibility artifact may differentially reduce signal in the anterior versus the posterior hippocampus. In the present study, we examined activation differences between hippocampal subregions during encoding and retrieval of words and interpreted our findings within the context of these two models. We also examined the extent to which susceptibility artifact affects the analysis and interpretation of hippocampal activation by demonstrating its differential effect on the anterior versus the posterior hippocampus. Both voxel‐by‐voxel and region‐of‐interest analyses were conducted, allowing us to quantify differences between the anterior and posterior aspects of the hippocampus. We detected significant hippocampal activation in both the encoding and retrieval conditions. Our data do not provide evidence for regional anatomic differences in activation between encoding and retrieval. The data do suggest that, even after accounting for susceptibility artifact, both encoding and retrieval of verbal stimuli activate the middle and posterior hippocampus more strongly than the anterior hippocampus. Finally, this study is the first to quantify the effects of susceptibility‐induced signal loss on hippocampal activation and suggests that this artifact has significantly biased the interpretation of earlier fMRI studies. Hippocampus 2003;13:164–174. © 2003 Wiley‐Liss, Inc.
Cellular mechanisms underlying the rhythmic bursts induced by NMDA microiontophoresis at the apical dendrites of CA1 pyramidal neurons
Authors: Bonansco Christian , Buño Washington
Published: January 2003

This article reports the cellular mechanisms underlying a form of intracellular “theta‐like” (θ‐like) rhythm evoked in vitro by microiontophoresis of N‐methyl‐D‐aspartate (NMDA) at the apical dendrites of CA1 pyramidal neurons. Rhythmic membrane potential (Vm) oscillations and action potential (AP) bursts (≈6 Hz; ≈20 mV; ≈2–5 APs) were evoked in all cells. The response lasted ≈2 s, and the initial oscillations were usually small (<20 mV) and below AP threshold. Rhythmic bursts were never evoked by imposed depolarization in the absence of NMDA. Block of Na+ conductance with tetrodotoxin (TTX) (1.5 μM), of non‐NMDA receptors with 6‐cyano‐7‐nitroquinoxaline‐2,3‐dione (CNQX) (20 μM) and of synaptic inhibition by bicuculline (50 μM) and picrotoxin (50 μM) did not prevent NMDA oscillation. Inhibition of the voltage dependence of the NMDA conductance in Mg2+‐free Ringer's solution blocked oscillations. Preventing Ca2+ influx with Ca2+‐free and Co2+ (2‐mM) solutions and block of the slow Ca2+‐dependent afterhyperpolarization (sAHP) by carbamilcholine (5 μM), isoproterenol (10 μM), and intracellular BAPTA blocked NMDA oscillations. Inhibition of L‐type Ca2+ conductance with nifedipine (30 μM) reduced oscillation amplitude. Block of tetraethylammonium (TEA) (10 mM) and 4AP (10 mM)‐sensitive K+ conductance increased the duration and amplitude, but not the frequency, of oscillations. In conclusion, θ‐like bursts relied on the voltage dependence of the NMDA conductance and on high‐threshold Ca2+ spikes to initiate and boost the depolarizing phase of oscillations. The repolarization is initiated by TEA‐sensitive K+ conductance and is controlled by the sAHP. These results suggest a role of interactions between NMDA conductance and intrinsic membrane properties in generating the CA1 θ‐rhythm. Hippocampus 2003;13:10067. © 2003 Wiley‐Liss, Inc.
Early life risk factors in cancer: The relation of birth weight to adult obesity
Authors: Leong Nicole M. , Mignone Laura I. , Newcomb Polly A. , Titus‐Ernstoff Linda , Baron John A. , Trentham‐Dietz Amy , Stampfer Meir J. , Willett Walter C. , Egan Kathleen M.
Published: January 2003

The intrauterine environment appears to play a role in the development of adult diseases, including several prominent cancers. Our study aims to characterize the relationship between birth weight, a measure of the intrauterine environment, and adult obesity. A population‐based sample of women aged 50–79, living in the states of Massachusetts, New Hampshire or Wisconsin, were randomly selected from lists of licensed drivers and Medicare beneficiaries to participate as controls in a case‐control study of breast cancer. Information on birth weight, adult height and adult weight were collected through structured telephone interviews from 1992–1995. Our analysis was based on 1,850 interviews. A U‐shaped relationship between birth weight and adult BMI was observed. Median adult BMI for the birth weight categories (in kilograms) <2.3, 2.3<2.5, 2.5<3.2, 3.2<3.9, 3.9<4.5 and ≥4.5 were 26.6, 24.4, 25.1, 25.5, 25.4 and 26.6 kg/m respectively. Compared to women 2.5<3.2 kg at birth, women in highest birth weight category (≥4.5 kg) had an odds ratio of 1.99 (95% CI 1.13–3.48) of being obese (≥30 kg/m2) as adults. The odds ratio for women in the <2.3 kg birth weight category was 1.67 (95% CI 1.01–2.76). These data suggest that both low and high birth weights are associated with higher adult BMI and support the hypothesis that fetal experience may influence adult obesity with potential consequences for risk of several major cancers. © 2002 Wiley‐Liss, Inc.
Does skin fibroblast radiosensitivity predict squamous cancer cell radiosensitivity of the same individual?
Authors: Haikonen Johanna , Rantanen Virpi , Pekkola Kirsi , Kulmala Jarmo , Grénman Reidar
Published: January 2003

Individualization of radiation doses is presumed to result in better radiotherapy outcome. Success rate in measuring radiosensitivity is probably the most limiting factor for present radiosensitivity assays to be introduced into clinical routine. To find a simpler predictive parameter, we compared the radiosensitivity of dermal fibroblasts and head and neck squamous cell carcinoma (SCC) cell lines established from the same individuals. The radiosensitivity was tested using the clonogenic 96‐well plate assay. The surviving fraction at 2.0 Gy (SF2) was determined, as well as the mean inactivation dose (AUC) of cancer cells. SF2 of SCC cell lines and skin fibroblasts were 0.25–0.44 and 0.11–0.43, respectively. AUC of SCC cells was 1.4–2.1 Gy. Dermal fibroblasts were more radiosensitive than SCC cells in 14 of 15 cases. In 1 patient (UT‐SCC‐8), cancer cells were found to be more radiosensitive than corresponding dermal fibroblasts. There was a clear tendency to a correlation between radiosensitivities of these 2 cell types, but statistical significance was reached only when the data of UT‐SCC‐8 was excluded. In our material, the intrinsic radiosensitivity of head and neck SCC cells could in most cases be predicted from the intrinsic radiosensitivity of dermal fibroblasts established from the same individual. © 2002 Wiley‐Liss, Inc.
Expression of the coxsackie and adenovirus receptor in human astrocytic tumors and xenografts
Authors: Fuxe Jonas , Liu Lu , Malin Stephen , Philipson Lennart , Collins V. Peter , Pettersson Ralf F.
Published: January 2003

The sensitivity of human tissues and tumors to infection with type C adenoviruses correlates with the expression of the human coxsackie B‐ and adenovirus receptor, hCAR. HCAR is heterogeneously expressed in various tissues and types of human cancer cells, which has implications for the use of adenoviruses as vectors in cancer gene therapy. Using immunoblotting, real‐time PCR, FACS‐analysis and sensitivity to infection with adenovirus‐lacZ, we analyzed the expression level of hCAR in glioma Grade IV cell lines. With real‐time PCR, we also analyzed hCAR expression in primary human astrocytomas of different malignancy grades, as well as in their xenograft derivatives. Analysis of a set of 10 cell lines showed great variation in hCAR expression. Susceptibility to Ad5lacZ correlated well with hCAR expression, whereas no correlation was observed with the expression of αvβ3/αvβ5 integrins, proposed to function as co‐receptors for adenoviruses. A great variation of CAR expression was also observed in primary astrocytomas of different malignancy grades. The mean value of CAR expression was significantly lower in 22 Grade IV tumors as compared to the values for 6 Grade II (p = 0.01) and 6 Grade III (p = 0.01) tumors. When the hCAR expression in 11 xenografts derived from Grade IV gliomas were compared to the levels detected in the original parental tumors, a mean 12‐fold higher expression was seen in the xenografts (P = 0.01). Two xenografts with low hCAR expression grew considerably faster than the hCAR‐expressing cells. Our results have relevance for the use of adenoviruses in gene therapy against astrocytomas. © 2002 Wiley‐Liss, Inc.
Ectopic p21sdi1 gene transfer induces retinoic acid receptor β expression and sensitizes human cancer cells to retinoid treatment
Authors: Teraishi Fuminori , Kadowaki Yoshihiko , Tango Yasuhisa , Kawashima Takeshi , Umeoka Tatsuo , Kagawa Shunsuke , Tanaka Noriaki , Fujiwara Toshiyoshi
Published: January 2003

The biological effects of retinoic acid (RA) are mediated by nuclear retinoic acid receptors (RARs) that function as ligand‐activated transcriptional factors. The response of human cancer cells to RA is known to be associated with the expression of RARβ. Recent studies have demonstrated that the loss of RARβ expression is involved in the development of a variety of human malignancies. We show that recombinant adenovirus‐mediated p21sdi1 gene transfer enhances RARβ mRNA expression as well as protein expression and induces the sensitivity to all‐trans RA (ATRA) in human cancer cells. Semi‐quantitative reverse transcription‐polymerase chain reaction analysis demonstrated that infection with adenovirus carrying human p21sdi1 gene (Ad5CMV‐p21), which encodes a cyclin‐dependent kinase inhibitor, induced RARβ mRNA and protein expression in H1299 human non‐small cell lung cancer cells and DLD‐1 human colorectal cancer cells. We also found that exogenous introduction of the p21sdi1 gene transcriptionally activated the upstream promoter function of the RARβ gene. Treatment with 1 μM of ATRA showed no significant inhibitory effects on the growth of H1299 and DLD‐1 cells; after Ad5CMV‐p21 infection, however, cells underwent apoptosis with ATRA treatment at the same concentration, suggesting that p21sdi1 gene transfer sensitized H1299 and DLD‐1 cells, presumably, through RARβ upregulation. We also demonstrated the efficacy of intratumoral injection of Ad5CMV‐p21 in combination with systemic administration of ATRA in a nude mice xenograft model. Our results indicate that recombinant adenovirus‐mediated p21sdi1 gene transfer could be potentially useful for the local induction of RA sensitivity in human premalignant and malignant lesions lacking appropriate RARβ expression. © 2002 Wiley‐Liss, Inc.
Characterization of the human Ly‐6 antigens, the newly annotated member Ly‐6K included, as molecular markers for head‐and‐neck squamous cell carcinoma
Authors: de Nooij‐van Dalen Arnolda G. , van Dongen Guus A.M.S. , Smeets Serge J. , Nieuwenhuis Eline J.C. , Stigter‐van Walsum Marijke , Snow Gordon B. , Brakenhoff Ruud H.
Published: January 2003

The E48 antigen is a successfully explored molecular marker for the diagnosis and therapy of HNSCC. The applicability of E48 as an HNSCC‐associated antigen, however, is restricted due to its heterogeneous expression in 30% of tumors; and identification of additional target antigens is therefore desired. E48 belongs to the Ly‐6 antigen family, comprising a group of highly homologous, low m.w., GPI‐anchored surface proteins, of which some show tissue‐restricted expression patterns. To identify novel human HNSCC‐associated Ly‐6 members with squamous cell‐associated expression patterns, we performed comprehensive gene‐screening consisting of BLAST searches within GenBank databases, followed by expression analysis. Using this approach, the Ly‐6K gene could be annotated as a novel member of the human Ly‐6 family. Expression of the human Ly‐6 genes E48, Ly‐6K, PSCA, GML,
RIG‐E, G6C and Ly‐6H was prescreened by qualitative RT‐PCR and subsequently analyzed by quantitative RT‐PCR in normal keratinocytes, HNSCC cell lines, normal mucosa, HNSCC tumors as well as normal peripheral blood and bone marrow cells. PSCA was highly expressed in normal mucosa, but 100‐fold decreased expression was seen in HNSCC. For Ly‐6H, GML and G6C, no or very low expression was observed in keratinocytes and HNSCC. Expression of RIG‐E was high in normal and malignant squamous cells and in peripheral blood and bone marrow cells, thus limiting its applicability as an HNSCC‐associated marker. In contrast, besides the E48 gene, the Ly‐6K gene also appeared to be selectively expressed in HNSCC and normal squamous cells. Moreover, expression of Ly‐6K was shown in HNSCC cell lines, in which no E48 expression could be detected. These data justify further evaluation of Ly‐6K as potential target antigen for the diagnosis and therapy of HNSCC. © 2002 Wiley‐Liss, Inc.
Effect of processing variables on texture development in a mica‐based glass–ceramic
Authors: Denry I. L. , Baranta G. , Holloway J. A. , Gupta P. K.
Published: January 2003

The purpose of this study was primarily to determine the feasibility of heat‐pressing a mica‐based glass–ceramic with the use of commercially available dental equipment, and secondly to evaluate the effect of various processing variables on the degree of crystal alignment in the pressed glass–ceramic. The hypotheses were that the mica‐based glass–ceramic could be successfully heat‐pressed and that some degree of crystal orientation would be obtained, depending on the processing variables. The glass composition was melted at 1400 °C for 2 h and cast into 12 × 60‐mm rods. Ingots (10 × 12 mm) were cut from the glass rods, heat treated, and heat‐pressed under various conditions. The microstructure of the pressed specimens was investigated by SEM and compared to that of heat‐treated controls. The length of Vickers‐induced cracks was measured on heat‐pressed specimens and heat‐treated controls. The results showed that mica‐based glass‐ceramics could be successfully pressed with the use of commercially available dental equipment. The resulting degree of crystal alignment (texture) along the direction of pressing varied between 35 ± 6 and 79 ± 6. There was a linear relationship between the degree of texture and the apparent aspect ratio of the mica platelets. A significant decrease in the length of the Vickers‐induced cracks in the direction perpendicular to pressing was observed, associated with an increase in length in the direction of pressing. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 64B: 70–77, 2002
In vitro corrosion testing of modular hip tapers
Authors: Goldberg Jay R. , Gilbert Jeremy L.
Published: January 2003

The in vivo fretting behavior of modular hip prostheses was simulated to determine the effects of material combination and a unique TiN/AlN coating on fretting and corrosion at the taper interface. Fretting current, open‐circuit potential (OCP), and quantities of soluble debris were measured to determine the role of mechanically assisted crevice corrosion on fretting and corrosion of modular hip tapers. Test groups consisting of similar‐alloy (Co‐Cr‐Mo head/Co‐Cr‐Mo neck), mixed‐alloy (Co‐Cr‐Mo head/Ti‐6Al‐4V neck), and TiN/AlN‐coated mixed‐alloy modular hip taper couples were used. Loads required to initiate fretting were similar for all test groups and were well below loads produced by walking and other physical activities. Decreases in OCP and increases in fretting current observed during long‐term cyclic loading were indicative of fretting and corrosion. Current measured after cessation of cyclic loading suggests that once the conditions for crevice corrosion are established, corrosion can continue in the absence of loading. The chemical, mechanical, and electrochemical measurements, along with microscopic inspections of the taper surfaces indicate that the fretting and corrosion behavior of similar‐ and mixed‐alloy taper couples are similar and that the coated samples are more resistant to fretting and corrosion. The results of this study clearly indicate the role of mechanical loading in the corrosion process, and support the hypothesis of mechanically assisted crevice corrosion. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 64B: 78–93, 2003
Porous titanium‐nickel for intervertebral fusion in a sheep model: Part 2. Surface analysis and nickel release assessment
Authors: Assad M. , Chernyshov A. V. , Jarzem P. , Leroux M. A. , Coillard C. , Charette S. , Rivard C. H.
Published: January 2003

Porous titanium‐nickel (PTN) devices represent an alternative to traditional cage implants. PTN materials possess an interconnecting network of pores with capillarity properties that may promote bone ingrowth, long‐term fixation, and intervertebral fusion without the need for bone grafting. However, their considerable surface area and nickel content may elicit concerns over sensitization potential. Therefore, PTN surface corrosion and nickel release resistance must be carefully studied. To evaluate this possibility, a PTN interbody fusion device (IFD) was compared to a conventional nonporous cage made of TiAlV, a well‐known biocompatible biomaterial, in a sheep model. PTN and TiAlV IFDs were inserted at two non‐contiguous lumbar sites for 3, 6, and 12 months postsurgery. Their surface was then evaluated by scanning electron microscopy (SEM) combined with backscattered electron analysis (BSE). No evidence of surface corrosion was observed either pre‐ or postimplantation, regardless of device type. Dosage of nickel ions was also performed with the use of inductively coupled plasma–mass spectrometry (ICP‐MS). Blood nickel levels were observed to be within acceptable levels at all postinstrumentation times. Nickel content in PTN‐adjacent tissue, as well as in detoxification and remote organs, was equivalent both in PTN‐treated and control sheep. Therefore, porous titanium‐nickel demonstrated resistance to both in vivo surface corrosion and nickel ion release and compared very well with a conventional titanium implant in the course of a 12‐month sheep study. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 64B: 121–129, 2003