bluuebunny/crossref_metadata_2025_split huggingface dataset:
Scanning electron microscopic observation of microvasculature in periodontium
Authors: Matsuo Masato , Takahashi Kazuto 
Published: August 2002

AbstractIn this study, vascular resin cast models in the periodontium of beagle dogs were prepared and three‐dimensional observation of the relationship between the gingiva and periodontal ligament (PDL) vascular network was performed. After the perfusion of Ringer's solution and fixative, synthetic resin was injected from the inferior alveolar arteries. Soft tissue was digested by proteinase solution and specimens were examined under scanning electron microscope (SEM). The gingival vascular network (GVN) in the region facing the teeth consisted of sulcular and junctional epithelium. The vascular network of the sulcular epithelium (SE) had a renal glomerulus‐like form and the junctional epithelium (JE) consisted of squamous mesh. The gingival sulcular fluid exudated from the vascular network directly beneath the JE, and leukocytes permeated from the vascular network beneath the epithelium. Thus, we considered that the GVN performs an important function in the protection against the inflammation. Periodontal ligament had a polygonal mesh vascular network that was anastomosed to the venous plexus of alveolar bone through Volkmann's canals (VC). When occlusal force was applied, the blood in the periodontal vessels flowed out through VC into the bone marrow, and when the force was removed, it flowed backward into the PDL. This blood transfer acted as an absorber against occlusal force. Our findings suggest that the blood vessels of the gingiva perform an important function in defending against inflammation, while the blood vessels of the PDL play a key role in absorbing occlusal force. Microsc. Res. Tech. 56:3–14, 2002. © 2002 Wiley‐Liss, Inc.
Oocyte growth and follicular hierarchy may be locally controlled by an inhibin‐like protein in the lizard Podarcis sicula
Authors: Limatola Ermelinda , Manzo Clotilde , Manzo Sonia , Monti Maria Gaia , Rosanova Patrizia , Romano Maurizio 
Published: August 2002

AbstractThe lizard Podarcis shows an ovarian annual cycle with three to four ovulatory waves between April and July (reproductive period). In August to September, a refractory stage occurs, followed by a nonreproductive period (October to March), during which the oocytes undergo slow growth and prepare themselves for vitellogenesis and ovulation. In the reproductive period, only a certain number of oocytes start growing, giving rise to a follicular hierarchy, which is controlled by still unknown mechanisms. In the present paper, immunoreactive inhibin was detected in previtellogenetic follicles of the reproductive period, and in particular, in the pyriform cells of the follicular epithelium. As the follicle grew and the pyriform cells disappeared, immunostaining shifted to the oocyte cytoplasm. The smaller follicles did not show any immunoreactivity. In the nonreproductive period, no follicles were labeled. We conclude that in the reproductive period, inhibin characterizes the follicles destined to ovulation and might be one of the main factors controlling follicular hierarchy. J. Exp. Zool. 292:96–102, 2002. © 2002 Wiley‐Liss, Inc.
Knowledge facts, knowledge fiction: the role of ICTs in knowledge management for development
Authors: Van Der Velden Maja 
Published: August 2002

AbstractWhat happens when corporate knowledge management monoculture meets the diverse international development sector? This paper finds that development agencies have too readily adopted approaches from the Northern corporate sector that are inappropriate to development needs. These approaches treat knowledge as a rootless commodity, and information and communications technology as a key knowledge tool. Alternative approaches are required, that focus on the knower and on the context for creating and sharing knowledge. ICT tools need to support this approach, helping people develop appropriate or alternative scenarios and improving the accessibility of information and knowledge for people with different cultural, social, or educational backgrounds. Copyright © 2002 John Wiley & Sons, Ltd.
Cyclopentadienyl technetium (99mTc) tricarbonyl piperidine conjugates: biodistribution and imaging studies
Authors: Saidi Mouldi , Kothari K. , Pillai M. R. A. , Hassan Amri , Sarma H. D. , Chaudhari P. R. , Unnikrishnan T. P. , Korde A. , Azzouz Zohra 
Published: August 2002

AbstractSynthesis of organometallic complexes of 99mTc using the precursor ligands N‐methylpiperidino‐4[(bispentahaptocyclopentadienyl)iron] carboxylate and N‐(isopropyl)‐piperidino‐4[(bispentahaptocyclopentadienyl)iron]carboxylate is described. The labelling method involved reaction of the ligands with 99mTcO in the presence of Mn(CO)5Br in dimethyl formamide at 150°C for 1 h in an oil bath. The purification of the complexes was carried out by preparative TLC using ethery/n‐butyl methyl amine (95:5) solvent system. The purified complexes were characterized by HPLC using acetonitrile:water (80:20) solvent system in a PRP‐1 column in which both the complexes were eluted as single peaks. Biodistribution studies carried out in rats showed 2.4±0.14 and 1.1±0.42% of the injected activity in the brain tissue 5 min p.i. for cytectrene I and II, respectively. The brain to blood activity ratio was >15:1 for both the complexes at 5 min p.i. Scintigraphic studies in rabbits showed significant uptake of the activity in the brain with fast clearance from blood. The complexes warrant further investigation as agents for brain imaging. Copyright © 2001 John Wiley & Sons, Ltd.
Effect of IL‐1β‐induced macromolecular depletion on residual quadrupolar interaction in articular cartilage
Authors: Borthakur Arijitt , Shapiro Erik M. , Beers Jennifer , Kudchodkar Sagar , Kneeland J. Bruce , Reddy Ravinder 
Published: August 2002

AbstractPurposeSodium multiple‐quantum filtered (MQF) NMR spectroscopy may potentially be used to measure proteoglycan (PG) depletion in cartilage caused by osteoarthritis (OA). The purpose of this work was to quantify the effect of interleukin‐1 (IL‐1β)‐induced macromolecule depletion on the residual quadrupolar interaction (RQI) of sodium in bovine cartilage plugs.Materials and MethodsFifteen 8‐mm‐diameter cartilage plug specimens were cored from the articular surface of fresh bovine patellae. All plugs were kept in culture media and nine of the plugs were subjected to interleukin‐1 (IL‐1β)‐induced degeneration of cartilage for 4, 6, and 7 days. Sodium NMR spectra were obtained from each sample with a 1‐cm‐diameter solenoid coil in a 2T whole‐body magnet interfaced to a custom‐built spectrometer. We employed a previously described theoretical model to analyze triple‐quantum filtered (TQF) and double‐quantum filtered magic angle (DQFMA) spectra obtained from normal cartilage and cartilage treated with IL‐1β. The model assumes a static Gaussian distribution of the RQI frequency, ωQ, in the sample. TQF and DQFMA spectra from each sample were fitted with the appropriate signal expressions to determine σ (the root mean square (RMS) ωQ), T2f, and T2s. An inversion‐recovery sequence was used to determine T1 of each plug. A spectrophotometric assay was used to determine the amount of PG depleted from each plug. Histology was performed to visualize the PG loss in cartilage plugs. We defined σ as the measure of changes in macroscopic order in the tissue.ResultsSimulated spectra from the theoretical model were in excellent agreement with the experimental data. We were able to determine the relaxation times as well as σ of each specimen from their corresponding fits. T2f ranged between
2.26–3.50 msec, decreasing with increased PG loss. Over the range of PG depletion investigated, T2s increased from 12.3 msec to 14.9 msec, and T1 increased from 16 msec to 21 msec, while σ decreased from 180 Hz to 120 Hz. The order of macromolecules in the cartilage tissue decreased substantially with PG loss. Histology sections clearly showed qualitative visualization of the PG loss in cartilage following treatment with IL‐1β.ConclusionWe demonstrated that IL‐β‐induced macromolecule depletion in cartilage not only changes the relaxation characteristics of sodium but also changes RQI of the tissue. Using MQF sodium spectroscopy we quantified the changes in σ and showed that loss of macromolecules reduces the degree of order in the tissue. J. Magn. Reson. Imaging 2002;15:315–323. © 2002 Wiley‐Liss, Inc.
Comparison of fat suppression strategies in 3D spiral coronary magnetic resonance angiography
Authors: Börnert Peter , Stuber Matthias , Botnar René M. , Kissinger Kraig V. , Manning Warren J. 
Published: August 2002

AbstractPurposeIn the present study, the impact of the two different fat suppression techniques was investigated for free breathing 3D spiral coronary magnetic resonance angiography (MRA). As the coronary arteries are embedded in epicardial fat and are adjacent to myocardial tissue, magnetization preparation such as T2‐preparation and fat suppression is essential for coronary discrimination.Material and MethodsFat‐signal suppression in three‐dimensional (3D) thin‐ slab coronary MRA based on a spiral k‐space data acquisition can either be achieved by signal pre‐saturation using a spectrally selective inversion recovery pre‐pulse or by spectral‐spatial excitation. In the present study, the performance of the two different approaches was studied in healthy subjects.ResultsNo significant objective or subjective difference was found between the two fat suppression approaches.ConclusionSpectral pre‐saturation seems preferred for coronary MRA applications due to the ease of implementation and the shorter cardiac acquisition window. J. Magn. Reson. Imaging 2002;15:462–466. © 2002 Wiley‐Liss, Inc.
MR pattern of hyperacute cerebral hemorrhage
Authors: Wintermark Max , Maeder Philippe , Reichhart Marc , Schnyder Pierre , Bogousslavsky Julien , Meuli Reto 
Published: August 2002

AbstractMagnetic resonance (MR) pattern of cerebral hemorrhage relates mainly to the relaxation and susceptibility effects of iron‐containing hemoglobin degradation products, as well as to their intra‐ or extracellular location. The purpose of this article is to report two acute stroke patients who underwent thrombolytic therapy and developed hyperacute cerebral hemorrhage during their admission cerebral MR survey. They constitute the earliest MR appearance of hyperacute intracerebral bleeding reported in the literature, featuring increased diffusion properties and persistent susceptibility effect on perfusion‐weighted imaging (PWI)‐series. J. Magn. Reson. Imaging 2002;15:705–709. © 2002 Wiley‐Liss, Inc.
The introduction of MR in the nordic countries with special reference to Norway: Central control versus local initiatives
Authors: Smith Hans‐Jørgen 
Published: August 2002

AbstractThe introduction of MR technology in Norway differed from that in Denmark, Finland and Sweden. In the latter countries, decisions were made at county or local level while in Norway the process was steered by the government and the national health authorities. For several reasons the steering was not very successful, and the intention of buying one MR unit ended with the purchase of five units. As a counter‐reaction, for seven years only university hospitals were allowed to purchase MR equipment. In 1993, the strict regulations were abolished, and during the succeeding years all four Nordic countries experienced similar exponential growth in the number of MR units. J. Magn. Reson. Imaging 2001;13:639–644. © 2001 Wiley‐Liss, Inc.
Improved mapping of pharmacologically induced neuronal activation using the IRON technique with superparamagnetic blood pool agents
Authors: Chen Yin‐Ching I. , Mandeville Joseph B. , Nguyen Tuong V. , Talele Anjali , Cavagna Friedrich , Jenkins Bruce G. 
Published: August 2002

AbstractThe use of functional magnetic resonance imaging (fMRI) techniques for evaluation of pharmacologic stimuli has great potential for understanding neurotransmitter dynamics for a number of brain disorders, such as drug abuse, schizophrenia, epilepsy, or neurodegeneration. Unfortunately, blood oxygenation level‐dependent (BOLD) imaging at common fields strengths, such as 1.5 or 3 T, has very low sensitivity and contrast‐to‐noise ratios (CNRs). We demonstrate here the utility of using an intravascular superparamagnetic iron oxide contrast agent with a long plasma half‐life for evaluation of hemodynamic changes related to dopaminergic stimuli using amphetamine or the cocaine analog 2β‐carbomethoxy‐3β‐(4‐fluorophenyl)tropane (CFT). We refer to this technique as increased relaxation with iron oxide nanoparticles (IRON). Results obtained here show that even at field strengths as high as 4.7 T, one can obtain increases in CNR by factors of 2–3 over BOLD imaging that lead to greater than an order of magnitude increase in statistical power with greatly increased sensitivity to hemodynamic changes in brain regions difficult to observe using BOLD imaging. Furthermore, use of the intravascular contrast agent allows for a meaningful physiologic parameter to be measured (relative cerebral blood volume (rCBV)), compared to conventional BOLD imaging. J. Magn. Reson. Imaging 2001;14:517–524. © 2001 Wiley‐Liss, Inc.
Cross‐checking of nanoelectrospray ionization mass spectrometry and computer simulation for the evaluation of the interaction strength of non‐covalently bound enkephalins in solution
Authors: Ishikawa Keiichiro , Nakamura Takako , Koga Yoshinori 
Published: August 2002

AbstractNanoelectrospray ionization mass spectrometry (nanoESI‐MS) and computer simulation were applied to the characterization of non‐covalent interactions of [Leu5]‐enkephalin (LE) and its optical isomers, [D‐Tyr1, Leu5]‐enkephalin (Y‐LE), [D‐Phe4, Leu5]‐enkephalin (F‐LE) and [D‐Tyr1, D‐Phe4, Leu5]‐enkephalin (YF‐LE). The dimer formation tendencies of the optical isomers of LE were evaluated by nanoESI‐MS using quadruply deuterated LE (H2N‐Tyr‐(2,2‐d2)Gly‐(2,2‐d2)Gly‐Phe‐Leu‐COOH, d4‐LE) as an internal standard. The relative interaction strengths of the optical isomers of LE were estimated to be Y‐LE < F‐LE < LE < YF‐LE. Geometry optimization calculations were performed for interactions in vacuo and in water using a semi‐empirical SCF method (PM3). The initial coordinate of the dimer structure of LE was taken from that obtained from single‐crystalline x‐ray diffraction analysis. Estimates of the interaction strengths of the dimer complexes were based on the heats of formation of a dimer complex (Hd) and the corresponding monomers (Hm) using the equation ΔH = Hd − 2Hm. The values of ΔH obtained from the calculations for interactions in water decreased in the order Y‐LE > F‐LE > LE > YF‐LE. Since the smaller values of ΔH correspond to stronger interactions between peptides, the results from computer simulations were qualitatively consistent with those obtained from the nanoESI experiments. The possibility of cross‐checking these independent techniques was demonstrated using medium‐sized molecules of biological importance. The agreement of the results from the two techniques suggested that nanoESI experiments, at least qualitatively, reflected the relative interaction strengths of non‐covalently bound enkephalins in aqueous solution. Copyright © 2001 John Wiley & Sons, Ltd.
Tuning compounds for electrospray ionization/in‐source collision‐induced dissociation and mass spectra library searching
Authors: Weinmann Wolfgang , Stoertzel Mylène , Vogt Susanne , Svoboda Michal , Schreiber André 
Published: August 2002

AbstractTuning compounds for positive and negative electrospray ionization (ESI) were tested for the tuning of in‐source collision‐induced dissociation (ESI/CID) with three types of SCIEX API instruments (API 365, 2000 and 3000) in the single‐quadrupole mode. The vacuum interfaces of these instruments differ slightly in geometry, but the principles of ionization and solvent evaporation by nebulizer and curtain gases, orifice and skimmer are identical. For comparison of in‐source CID, breakdown curves of haloperidol, paracetamol, metronidazole and metamizole were acquired by increasing the orifice voltages. The API 2000 and 3000 required higher orifice voltages than did the API 365 to induce a similar degree of fragmentation of the protonated or deprotonated molecules to characteristic fragment ions. This increase of orifice voltage could be demonstrated with each of the four compounds tested by a shift of the maxima of the breakdown curves to higher orifice voltages. A procedure with three collision energy (CE) levels for drug identification with a mass spectra library set up with an API 365 therefore required an adjustment of the orifice voltages to higher values when being transferred to an API 2000 or API 3000. The corresponding orifice voltages for the three instruments were 20/50/80 V (API 365), 30/90/130 V (API 2000) and 40/80/120 V (API 3000). However, a change in orifice voltage of ±10 V (with the API 2000 and 3000) hardly influenced the fit values of a library search for each single CE level. For adjusting orifice voltages with different instruments, a tuning procedure with haloperidol and paracetamol is presented. With this tuning procedure an ESI/CID mass spectra library set up for API 365 and API 150 could also be used for drug identification with an API 2000 and an API 3000 with good library search results. Copyright © 2001 John Wiley & Sons, Ltd.
Enterovirus sequences resembling coxsackievirus A2 detected in stool and spleen from a girl with fatal myocarditis
Authors: Bendig Justin W.A. , O'Brien Patrick S. , Muir Peter , Porter Helen J. , Caul E. Owen 
Published: August 2002

AbstractA 10‐year‐old girl who died suddenly was found at post mortem to have myocarditis. Virus could not be cultured from post‐mortem stool, spleen or heart but enterovirus RNA was detected in stool and spleen by PCR, and the stool caused flaccid paralysis in newborn suckling mice. A 654 base pair (bp) sequence from the capsid‐coding region of the viral genome was amplified from an affected mouse and sequenced. Using this sequence, strain‐specific nested primers were designed and used to amplify viral sequences directly from stool and spleen. These sequences were identical to each other and to that obtained from the infected mouse, and most closely resembled Coxsackievirus A2, an uncommon serotype rarely associated with myocarditis. Testing spleen tissue may be useful in etiological investigation of suspected viral myocarditis. PCR proved more sensitive than suckling mouse inoculation in detecting this Coxsackievirus, but a combination of both methods was required for genotypic characterization. J. Med. Virol. 64:482–486, 2001. © 2001 Wiley‐Liss, Inc.
Pyramidal and extrapyramidal involvement in experimental infection of cynomolgus monkeys with enterovirus 71
Authors: Nagata Noriyo , Shimizu Hiroyuki , Ami Yasushi , Tano Yoshio , Harashima Ayako , Suzaki Yuriko , Sato Yuko , Miyamura Tatsuo , Sata Tetsutaro , Iwasaki Takuya 
Published: August 2002

AbstractAmong the enteroviruses, polioviruses and enterovirus 71 (EV71) are two major neurotropic viruses causing serious neurological manifestations. While polioviruses are being eradicated globally by vaccination, EV71 still has the potential to cause a large outbreak such as that in Taiwan in 1998, in which there were many fatalities. In this study, we determined the neurovirulence of EV71 by neuropathological analysis of cynomolgus monkeys after experimental infection with five EV71 strains, which were isolated from individual patients with fatal encephalitis; meningitis; and hand, foot, and mouth disease. After intraspinal inoculation, the monkeys developed neurological manifestations within 1–6 days post‐inoculation, irrespective of the inoculated strains. These manifestations included not only pyramidal tract signs such as flaccid paralysis, but also extrapyramidal tract signs such as tremor and ataxia. Histological and viral examinations confirmed virus replication in the spinal cord, brainstem, cerebellar cortex, and dentate nuclei, and cerebrum. The strains isolated during the 1970s and 1990s showed no particular differences with respect to neurotropism. Thus, it is clear that EV71 has a wider neurotropism than that of polioviruses. J. Med. Virol. 67:207–216, 2002. © 2002 Wiley‐Liss, Inc.
Nitric oxide‐induced programmed cell death in human neuroblastoma cells is accompanied by the synthesis of Egr‐1, a zinc finger transcription factor
Authors: Cibelli Giuseppe , Policastro Vincenza , Rössler Oliver G. , Thiel Gerald 
Published: August 2002

AbstractNitric oxide (NO) is cytotoxic for human SH‐SY5Y neuroblastoma cells. While nuclear condensation was visible in cells treated with nitric oxide donors, we observed that the plasma membrane remained intact, indicating that NO induced apoptotic cell death. We analyzed the NO‐induced apoptotic signaling cascade in SH‐SY5Y cells and observed a striking increase in early growth response (Egr)‐1 promoter activity as a result of NO‐induced cell death. Likewise, we detected an activation of the transcriptional activation potential of the ternary complex factor Elk1, a key transcriptional regulator of serum response element‐driven gene transcription. Egr‐1 is a zinc finger transcription factor that couples extracellular signals to long‐term responses by altering expression of Egr‐1 target genes. The Egr‐1 5′‐flanking region contains five serum response elements (SRE) that function as genetic elements for stimulus‐transcription coupling. Moreover, these SREs are binding sites for Elk1, suggesting that NO activated Egr‐1 gene transcription via activation of Elk1. The NO‐induced biosynthesis of Egr‐1 was confirmed by Western blot analysis and an NO‐dependent increase in the transcriptional activation potential of Egr‐1 was observed. The fact that NO‐induced neuronal cell death is accompanied by the biosynthesis of Egr‐1 suggests that Egr‐1 may be an integral part of the NO triggered apoptotic signaling cascade. © 2002 Wiley‐Liss, Inc.
Trafficking of axonal K+ channels: Potential role of Hsc70
Authors: Clay John R. , Kuzirian Alan 
Published: August 2002

AbstractVoltage‐gated potassium ion channels in axons underlie the repolarization phase of the membrane action potential and help to set the resting potential. In addition to being present in the axolemma, they are also found in axoplasm in small vesicles, 30–50 nm in diameter, which may serve as a reserve pool of K+ channel protein (Clay and Kuzirian [2000] J Neurobiol 45:172–184). We have developed a novel technique for extracting these vesicles from axoplasm, which relies on the ability of Texas red to bind to them, thereby reducing their buoyancy so that they are amenable to pelleting by ultracentrifugation (Clay and Kuzirian [2000] J Neurobiol 45:172–184). The mechanism underlying this process may be binding of Texas red to Hsc70, which is primarily a cytosolic protein. However, a small portion of it is located on the surface of vesicles. Kinesin is also on the vesicle surface. This protein is membrane bound in our in vitro vesicle preparation when solutions that do not contain MgATP are added to extruded axoplasm. The addition of MgATP to the solution appears to release a significant amount of kinesin from the vesicles, possibly by the Hsc70‐MgATP catalysis mechanism recently proposed by Tsai et al. Published 2002 Wiley‐Liss, Inc.