bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of bioresorbable, unsintered hydroxyapatite/poly‐L‐lactide composite films on spinal cord, nerve roots, and epidural space
Authors: Matsumoto Masanori , Chosa Etsuo , Nabeshima Kazuki , Shikinami Yasuo , Tajima Naoya 
Published: August 2002

AbstractThe effect of forged unsintered hydroxyapatite/poly‐L‐lactide (u‐HA/PLLA) composite films on spinal cord and nerve roots and its degradation behavior and osteoconductivity in epidural space were compared with those of calcined HA (c‐HA)/PLLA and unfilled PLLA films. Partial laminectomy was performed on 20 rabbits, and u‐HA/PLLA and PLLA films were implanted in the intervertebral space. Total laminectomy was performed on 30 rabbits to implant u‐HA/PLLA, c‐HA/PLLA, and PLLA films in both epidural and subcutaneous spaces. For up to 50 weeks, there were no histological changes in the spinal cord or nerve root, and no inflammatory cell infiltration into the epidural space around the films. The rate of decrease in viscosity average molecular weight of both composite films was initially higher than that of PLLA but eventually became lower, although there was no difference in the degradation behavior of the three films in either the epidural or subcutaneous spaces after 50 weeks. Scanning electron microscopic and energy‐dispersive X‐ray analysis indicated calcium phosphate deposits on the surface of composite films with new bone formation from 4 weeks. The u‐HA/PLLA composite film therefore has good biocompatibility, osteoconductivity, and fast primary degradation rate, which may prove compatible with application to spinal surgery. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 60: 101–109, 2002
Macrophages take up triacylglycerol‐rich emulsions at a faster rate upon co‐incubation with native and modified LDL: An investigation on the role of natural chylomicrons in atherosclerosis
Authors: Carvalho Márcia D.T. , Harada Lila M. , Gidlund Magnus , Ketelhuth Daniel F.J. , Boschcov Paulo , Quintão Eder C.R. 
Published: August 2002

AbstractChylomicrons play a role in atherosclerosis, however, because the mechanisms involved in the cell uptake of these particles are not fully understood, investigations were carried out using a radioactively labeled protein‐free triacylglycerol‐rich emulsion incubated with peritoneal macrophages obtained from normal and apoE‐knockout mice. Experiments were done in the presence of substances that inhibit several endocytic processes: EDTA for low density lipoprotein receptor, fucoidan for scavenger receptor, cytochalasin B for phagocytosis, and a lipopolysaccharide for lipoprotein lipase. In addition, triacylglycerol‐rich emulsions were also prepared in the presence of native or modified radioactively labeled low density lipoprotein particles that are known to accumulate in the arterial intima. Probucol was also used to prevent the possible role played by an antioxidant in triacylglycerol‐rich emulsion uptake. We have shown that triacylglycerol‐rich emulsion alone is taken up by a coated‐pit‐dependent mechanism, mediated by macrophage secretion of apolipoprotein E. Furthermore, native, aggregated, acetylated, and moderately macrophage‐oxidized low density lipoprotein stimulate the uptake of a triacylglycerol‐rich emulsion through several mechanisms such as an actin‐dependent pathway, scavenger receptors, and lipolysis mediated by lipoprotein lipase. On the other hand, in spite of the interaction of low density lipoprotein forms with a triacylglycerol‐rich emulsion, the cellular triacylglycerol‐rich emulsion uptake is impaired by copper‐oxidized low density lipoprotein, possibly due to its diminished affinity towards lipoprotein lipase. We have also shown that macrophages take up aggregated low density lipoprotein better than the acetylated or oxidized forms of low density lipoprotein. J. Cell. Biochem. 84: 309–323, 2002. © 2001 Wiley‐Liss, Inc.
Endogenous regucalcin suppresses the enhancement of protein phosphatase activity in the cytosol and nucleus of kidney cortex in calcium‐administered rats
Authors: Morooka Yoshiko , Yamaguchi Masayoshi 
Published: August 2002

AbstractThe suppressive role of endogenous regucalcin (RC), which is a regulatory protein of calcium signaling, in the enhancement of protein phosphatase activity (PPA) in the cytosol and nucleus of kidney cortex in calcium‐administered rats was investigated. Calcium content in the kidney cortex was significantly increased at 0.5–5 h after a single intraperitoneal administration of calcium chloride solution (10 mg Ca/100 g body weight) to rats. The analysis with Western blotting of RC protein showed that RC levels in the cytosol and nucleus were significantly increased 0.5–5 h after the administration of calcium (10 mg/100 g). PPA toward phosphotyrosine, phosphoserine, and phosphothreonine was found in the cytosol and nucleus of kidney cortex. PPA toward three phosphoamino acids in the cytosol and nucleus was significantly increased by the administration of calcium (10 mg/100 g). The presence of anti‐RC monoclonal antibody (25 ng/ml) in the enzyme reaction caused a significant increase in PPA toward phosphotyrosine, phosphoserine, and phosphothreonine in the cytosol and nucleus of kidney cortex in normal rats. The effect of anti‐RC monoclonal antibody (25 ng/ml) in increasing PPA toward three phosphoamino acids in the cytosol and nucleus was significantly enhanced in calcium‐administered rats. The effect of anti‐RC monoclonal antibody (25 ng/ml) in increasing PPA in the cytosol and nucleus of normal rats and calcium‐administered rats was completely abolished by the addition of RC (10− 6 M) in the enzyme reaction mixture. The present study suggests that endogenous RC suppresses the enhancement of PPA in the cytosol and nucleus of kidney cortex in calcium‐administered rats. J. Cell. Biochem. 85: 553–560, 2002. © 2002 Wiley‐Liss, Inc.
Differential sensitivity to apoptosis between the human small and large intestinal mucosae: Linkage with segment‐specific regulation of Bcl‐2 homologs and involvement of signaling pathways*
Authors: Gauthier Rémy , Laprise Patrick , Cardin Éric , Harnois Charlène , Plourde Annie , Reed John C. , Vézina Anne , Vachon Pierre H. 
Published: August 2002

AbstractThe small and large intestines differ in their expression profiles of Bcl‐2 homologs. Intestinal segment‐specific Bcl‐2 homolog expression profiles are acquired as early as by mid‐gestation (18–20 weeks) in man. In the present study, we examined the question whether such distinctions underlie segment‐specific control mechanisms of intestinal cell survival. Using mid‐gestation human jejunum and colon organotypic cultures, we analyzed the impact of growth factors (namely insulin; 10 μg/ml) and pharmacological compounds that inhibit signal transduction molecules/pathways (namely tyrosine kinases, Fak, PI3‐K/Akt, and MEK/Erk) on cell survival and Bcl‐2 homolog expression (anti‐apoptotic: Bcl‐2, Bcl‐XL, Mcl‐1; pro‐apoptotic: Bax, Bak, Bad). The relative activation levels of p125Fak, p42Erk‐2, and p57Akt were analyzed as well. Herein, we report that (1) the inhibition of signal transduction molecules/pathways revealed striking differences in their impact on cell survival in the jejunum and colon (e.g., the inhibition of p125Fak induced apoptosis with a significantly greater extent in the jejunum [∼43%] than in the colon [∼24%]); (2) sharp distinctions between the two segments were noted in the modulatory effects of the various treatments on Bcl‐2 homolog steady‐state levels (e.g., inhibition of tyrosine kinase activities in the jejunum down‐regulated all anti‐apoptotics analyzed while increasing Bax, whereas the same treatment in the colon down‐regulated Bcl‐XL only and increased all pro‐apoptotics); and (3) in addition to their differential impact on cell survival and Bcl‐2 homolog expression, the MEK/Erk and PI3‐K/Akt pathways were found to be distinctively regulated in the jejunum and colon mucosae (e.g., insulin in the jejunum increased p42Erk‐2 activation without affecting that of p57Akt, whereas the same treatment in the colon decreased p42Erk‐2 activation while increasing that of p57Akt). Altogether, these data show that intestinal cell survival is characterized by segment‐specific susceptibilities to apoptosis, which are in turn linked with segmental distinctions in the involvement of signaling pathways and the regulation of Bcl‐2 homolog steady‐state levels. Therefore, these indicate that cell survival is subject to segment‐specific control mechanisms along the proximal‐distal axis of the intestine. J. Cell. Biochem. 82: 339–355, 2001. © 2001 Wiley‐Liss, Inc.
Intensity‐carrying modes important for vibrational polarizabilities and hyperpolarizabilities of molecules: Derivation from the algebraic properties of formulas and applications
Authors: Torii Hajime 
Published: August 2002

AbstractThe intensity‐carrying mode (ICM) theory is developed for analyzing the vibrational motions that mainly contribute to vibrational polarizabilities and hyperpolarizabilities, which are important for describing intermolecular electrostatic interactions and nonlinear optical properties of molecules. The ICMs are derived from dipole derivatives, polarizability derivatives, and first hyperpolarizability derivatives by using algebraic properties of intensity formulas. The way to obtain explicit forms of ICMs, including the optimization method of the basis of the ICM vector space, is discussed in detail. One‐ and two‐dimensional models are constructed on the basis of the ICMs. The theory is applied to three molecules (a push–pull type polyene, a streptocyanine dye cation, and a symmetric neutral polyene) taken as typical examples. It is shown that the ICM theory provides a reasonable picture on the vibrational polarization properties of these molecules. On the basis of this result, the validity of the valence‐bond charge transfer (VB‐CT) model, which is a one‐dimensional model and is widely used to describe the electronic and vibrational properties of dye molecules, is also discussed. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 997–1006, 2002
Calculation of sequence‐dependent free energies of hydration of dipeptides formed by alanine and glycine
Authors: Loeffler Hannes H. , Sotriffer Christoph A. , Winger Rudolf H. , Liedl Klaus R. , Rode Bernd M. 
Published: August 2002

AbstractThe relative free energies of hydration of the dipeptides glycylalanine and alanyl‐glycine in their naturally occurring form have been calculated both for the zwitterionic and protonated species. Emphasis was laid on comparisons between the conventional cutoff method and the Particle Mesh Ewald method to account for possible differences in electrostatic contributions to the free energy. Furthermore, the convergence behavior of the total free energy and its individual contributions were examined. The results, obtained by means of the thermodynamic integration technique as implemented in the free energy module of the AMBER program suite, suggest that in aqueous solution glycylalanine is more stable than alanylglycine by 2.7 kcal/mol in the zwitterionic form and by 3.5 kcal/mol in the protonated form. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 846–860, 2001
Correspondence between GTO and STO molecular basis sets
Authors: Fernández Rico J. , López R. , Ramírez G. , Ema I. 
Published: August 2002

AbstractWe present a method for the characterization of the distance between two spaces: one generated by a Gaussian basis set, and another by a Slater basis set. The method is an extension of one previously developed for atoms that has been modified to cover molecular problems. The current version enables us to obtain Slater basis sets capable of reproducing the results (multielectronic wave functions and orbitals) obtained with Gaussian basis sets. The interest of this result arises from the fact that we will be able to profit from the effort invested in the optimization of high‐quality Gaussian basis sets. © 2001 John Wiley & Sons, Inc. J Comput Chem 22: 1655–1665, 2001
Theoretical study on the mechanism of the gas‐phase reaction of diborane(3) anion with carbon disulfide
Authors: Qu Zheng‐wang , Zhu Hui , Li Ze‐sheng , Zhang Qi‐yuan 
Published: August 2002

AbstractThe complex potential energy surface of the gas‐phase reaction of HB(H)BH− with CS2 to give three low‐lying products [B2H3S]−+CS, [BH2CS]−+HBS, and [BH3CS]+BS−, involving nine [B2H3CS2]− isomers and 12 transition states, has been investigated at the CCSD(T)/6‐311++G(d,p)//B3LYP/6‐311++G(d,p) level. Our calculations are in harmony with the recent experimental and theoretical results, and reveal some new bonding and kinetic features of this reaction system. Our theoretical results may help the further identification of the products [BH2CS]−+HBS and [BH3CS]+BS− and may provide useful information on the chemical behaviors of other electron‐deficient boron hydride anions. © 2002 Wiley Periodicals, Inc. J Comput Chem 23: 414–419, 2002
Mechanisms of P2 receptor‐evoked DNA synthesis in thyroid FRTL‐5 cells
Authors: Ekokoski Elina , Webb Tania E. , Simon Joseph , Törnquist Kid 
Published: August 2002

AbstractThe expression of the P2 receptors and their functional responses were studied in rat thyroid FRTL‐5 cells. RT‐PCR analysis revealed transcripts for the G protein‐coupled P2Y2, P2Y4 and P2Y6 receptors, and for the transmitter‐gated ion channel P2X3, P2X4 and P2X5 subunits. In Fura‐2‐loaded cells, UTP, ATP, ATPγS or UDP increased [Ca2+]i, and behaved as potent full agonists, while 2‐Methylthio‐ATP (2‐MeSATP), α,β‐methylene‐ATP (α,β‐meATP) and pure ADP were weak agonists. The agonist‐mediated [Ca2+ ]i increases were diminished in Ca2+ ‐free buffer, and by pertussis toxin (PTX) or suramin treatments. ATP, UTP, UDP and ATPγS increased 3H‐thymidine incorporation into DNA and expression of the protooncogenes c‐Fos and c‐Jun, while 2‐MeSATP was ineffective, and α,β‐meATP gave a response only at 100‐μM dose. The ATP‐stimulated expression of c‐Fos and c‐Jun was dependent on Ca2+, and protein kinase C, but not on calmodulin or Ca2+/calmodulin‐dependent protein kinase II. Extracellular signal‐regulated kinases (ERK1 and ERK2) are also involved as the MEK inhibitor, PD98059, reduced both ATP‐evoked 3H‐thymidine incorporation and c‐Fos and c‐Jun expression. These results indicate that multiple P2Y receptor subtypes and at least the P2X5 subtype are functionally expressed in FRTL‐5 cells, and that nucleotides acting via P2 receptors are involved in the regulation of DNA‐synthesis. © 2001 Wiley‐Liss, Inc.
Reduction of c‐myc expression by an antisense approach under Cre/loxp switching induces apoptosis in human liver cancer cells
Authors: Ebinuma Hirotoshi , Saito Hidetsugu , Kosuga Motomichi , Wakabayashi Kanji , Saito Yoshimasa , Takagi Tamako , Nakamoto Nobuhiro , Okuyama Torayuki , Ishii Hiromasa 
Published: August 2002

Abstractc‐Myc has been documented to be both a positive and a negative signal for the induction of apoptosis. It is well known that overexpression of the c‐myc gene induces apoptosis of normal cells, but the result of a reduction in its expression is not fully understood. We examined whether a reduction in c‐myc expression would induce apoptosis in human liver cancer cells. Specifically, antisense and sense oligodeoxynucleotides (oligos) against the human c‐myc mRNA were synthesized, mixed with a liposome reagent at various ratios, and were applied to the liver cancer‐derived cell lines, HCC‐T, HepG2, and PLC/PRF/5. To exclude effects resulting from using oligos, plasmid vectors expressing the full‐length c‐myc cDNA in both sense and antisense orientations under the control of the Cre/loxP system were generated. Monoclonal cell lines including these plasmid vectors were produced and Cre was supplied by adenovirus infection. Apoptosis was determined morphologically and c‐Myc and Bcl‐2 expression was examined by Western blotting. The antisense myc significantly inhibited the proliferation of the cells within two days, while neither the liposome reagent alone nor sense myc did so. Most of the cells were rounded up by the antisense‐treatment and nuclear fragmentation and DNA ladder formation were detected after two days in antisense c‐myc‐treated cells. Antisense c‐myc largely reduced c‐Myc and partially Bcl‐2 expression; overexpression of Bcl‐2 partially rescued from apoptosis in HCC‐T and HepG2 cells. These results suggest that the massive reduction in c‐myc mRNA induces apoptosis in liver cancer cell lines and consequent decrease in Bcl‐2 enhances the cell death. c‐Myc reduction under the Cre/loxP switching system may be a useful tool for the clarification of c‐myc‐related cellular mechanisms in differentiation and proliferation. © 2001 Wiley‐Liss, Inc.
Pyrolysis of tetra pack in municipal solid waste
Authors: Wu Chao‐Hsiung , Chang Hwa‐Shan 
Published: August 2002

AbstractThe pyrolysis of tetra pack in nitrogen was investigated with a thermogravimetric analysis (TGA) reaction system. The pyrolysis kinetics experiments for the tetra pack and its main components (kraft paper and low‐density poly(ethene) (LDPE)) were carried out at heating rates (β) of 5.2, 12.8, 21.8 K min−1. The results indicated that the one‐reaction model and two‐reaction model could be used to describe the pyrolysis of LDPE and kraft paper respectively. The total reaction rate of tetra pack can be expressed by the summation of the individual class of LDPE and kraft paper by multiplying the weighting factors. The pyrolysis products experiments were carried out at a constant heating rate of 5.2 K min−1. The gaseous products were collected at room temperature (298 K) and analyzed by gas chromatography (GC). The residues were collected at some significant pyrolysis reaction temperatures and analyzed by an elemental analyzer (EA) and X‐ray powdered diffraction (XRPD). The accumulated masses and the instantaneous concentrations of gaseous products were obtained under the experimental conditions. The major gaseous products included non‐hydrocarbons (CO2, CO, and H2O) and hydrocarbons (C1–5). In the XRPD analysis, the results indicated that pure aluminum foil could be obtained from the final residues. The proposed model may be supported by the pyrolysis mechanisms with product distribution.© 2001 Society of Chemical Industry
Selective copper–iron dissolution from a molybdenite concentrate using bacterial leaching
Authors: Romano Patricia , Blázquez María Luisa , Ballester Antonio , González Felisa , Alguacil Francisco José 
Published: August 2002

AbstractThe present research reports on the selective dissolution of copper and iron from a Chilean molybdenite concentrate using mesophilic, moderate and extreme thermophilic culture bacteria. From the results obtained it is deduced that molybdenite is not attacked by any of the above mentioned microorganisms, whereas the attack of the copper–iron species is dependent on various experimental conditions: pH, potential, pulp density, or addition of silver as catalyst. Optimal copper–iron dissolution is obtained using extreme thermophilic microorganisms and low pulp density (2% w/v). Total selective dissolution of chalcopyrite is achieved which leads to a pure molybdenite concentrate being obtained.© 2001 Society of Chemical Industry
Study of perovskite‐type oxides and their supported Ag derivatives for catalytic oxidation of diesel soot
Authors: Liu Zhiming , Hao Zhengping , Zhang Huiping , Zhuang Yahui 
Published: August 2002

AbstractA series of perovskite‐type oxides and derived Ag catalysts were prepared, and characterized by N2‐adsorption, X‐ray diffraction and X‐ray photoelectron spectroscopy. The influences of pretreatment and Ag loading on catalytic activity for diesel soot oxidation were also investigated. Prereduction resulted in a decrease in catalytic activity. An increase in activity with Ag addition was observed, especially with more than 5% Ag loading. This catalyst could be a promising candidate for the catalytic elimination of diesel soot.© 2002 Society of Chemical Industry
Three‐dimensional wall structure and the innervation of dental pulp blood vessels
Authors: Iijima Tadahiko , Zhang Jing‐Qi 
Published: August 2002

AbstractThe involvement of neural components in plasma extravasation and blood flow in the dental pulp has been established by pharmacological and physiological studies. We review here the segmental constitution of pulp vessels and the possible involvement of neural components in both the contractility and permeability of the pulp vessels from a morphological viewpoint. Six vascular segments can be identified based on the morphology of peri‐endothelial cells, such as smooth muscle cells and pericytes. These are: muscular arterioles, terminal arterioles, precapillary arterioles, capillaries, postcapillary venules, and collecting or muscular venules. The perivascular nerve forms a mesh with numerous terminal varicosities, some of which attach directly to arteriolar smooth muscle cells. This mesh can be seen by scanning electron microscopy, and indicates the important role of neural components in regulating the pulpal circulation. After administering norepinephrine (0.2 mg/kg/dog), the surface texture of the smooth muscle cells of pulp arterioles reveals marked irregularities, which are correlated with arteriolar contraction. The pericytes in larger postcapillary venules (diameter 20 μm or larger) also show irregularities, whereas no changes are seen in the pericytes of either smaller postcapillary venules or capillaries. The intercellular spaces of pericytes in the postcapillary venules are wide enough for leukocytes to pass through, and the occasional extravasation of leukocytes through venule walls can be seen under electron microscopy. The microvessels of healthy human dental pulp react weakly to selectins, indicating that apparently healthy dental pulp may be weakly inflamed. In rat dental pulp, CGRP‐immunoreactive nerves and nerve terminals containing many granular vesicles supply the postcapillary venules more densely than the arterioles, which suggests the involvement of postcapillary venules in neurogenic inflammation in the dental pulp. Microsc. Res. Tech. 56:32–41, 2002. © 2002 Wiley‐Liss, Inc.
Histochemical and ultrahistochemical localization of heavy metals in calf organs
Authors: Horký D. , Illek J. , Pechová A. 
Published: August 2002

AbstractCadmium, zinc, selenium, and copper were administered, singly or in combination, orally or subcutaneously. Experiment I included 32 calves of both sexes; six received Cd (two groups), Zn, Cd, and Zn, and Cd and Se (two groups) and one group was a control. In Experiment II (21 bulls), three were given Cd, Cd, and Cu, and Cd and Zn, respectively, and one group was a control. For light microscopy, in Experiment I the highest amounts of silver granules were present in the samples of liver, small intestine, and vesicular gland of all the exposed groups; in Experiment II the most affected organs were liver, kidney, and small intestine. For electron microscopy, in Experiment I, after administration of Cd and Zn, the highest amounts of granules were seen in the cytoplasm of hepatocytes and cells of the proximal and distal renal tubules and the lowest amounts were found in glandular cells of the pancreas. Administration of Cd and Se resulted in the presence of large numbers of granules in the nuclei and nucleoli of spermatogonies. In Experiment II, ingestion of Cd and Zn in feed led to the appearance of highest amounts of granules in the nucleoli, nuclei, and cytoplasm of cells in testes, kidneys, and pancreas. Following Cd intake, the highest accumulation of granules was observed in the nucleoli of hepatocytes and cells of the proximal and distal renal tubules. Combined Cd and Cu produced the highest number of granules in cells of the proximal and distal renal tubules and in the nucleoli and nuclei of germinal epithelium. Microsc. Res. Tech. 56:435–450, 2002.