bluuebunny/crossref_metadata_2025_split huggingface dataset:
Topical Application of Drugs Influencing Cytoskeleton and Cell Contractility Affects Alveolar Bone Loss in Rats
Authors: Yaffe Avinoam , Bahar Hila , Binderman Itzhak 
Published: May 2006

Background: Several studies have shown that sectioning bundles of collagen fibers in the marginal gingiva during surgical procedures in animals is a distinct stimulus for alveolar bone resorption. Normally, gingival and periodontal fibroblasts, which reside on these collagen fibers, create physiological traction forces generated by the cytoskeleton. By splitting the fibers, traction forces are released, inducing changes in the cytoskeleton and cell shape. In this study, four drugs were selected, including cytochalasin D, EDTA, sodium orthovanadate, and H‐7, all influencing the cytoskeleton‐integrin‐extracellular matrix (ECM) pathway, for their ability to reduce alveolar bone loss by local application.Methods: The drugs were applied locally only once at the site of mucoperiosteal flap surgery in a rat model. Cytochalasin D (1 μl/μl), EDTA (0.24 mg/μl), sodium orthovanadate (0.02 mg/μl), and H‐7 (0.10 μl/ μl), each separately, were carried by a protective paste and placed immediately after elevating the flap. The analysis of alveolar bone loss was performed 3 weeks after surgery by scanning the microradiographic films of the mandible cross‐sections. The percentages of cross sections with no, moderate, or severe bone loss in treated in comparison to non‐treated rats are presented.Results: EDTA, sodium orthovanadate, and H‐7 were significantly effective in reducing alveolar bone loss. They were effective in reducing the amount of severe bone loss by 53%, 20%, and 58% while increasing the number of sections with no bone loss by 25%, 23%, and 35%, respectively. Cytochalasin D reduced alveolar bone loss insignificantly.Conclusion: EDTA, sodium orthovanadate, and H‐7 are effective in reducing alveolar bone loss in rats following mucoperiosteum surgery.
Promotion of Functioning of Human Periodontal Ligament Cells and Human Endothelial Cells by Nerve Growth Factor
Authors: Xu Wan‐Peng , Mizuno Noriyoshi , Shiba Hideki , Takeda Katsuhiro , Hasegawa Naohiko , Yoshimatsu Shinitiro , Inui Takafumi , Ozeki Yoshitaka , Niitani Miyuki , Kawaguchi Hiroyuki , Tsuji Koichiro , Kato Yukio , Kurihara Hidemi 
Published: May 2006

Background: We have previously shown that cultured human periodontal ligament (HPL) cells produce nerve growth factor (NGF) and express mRNA of tyrosine kinase receptor (trkA), a high‐affinity receptor of NGF. These findings suggest that NGF modulates the differentiation and proliferation of the periodontal ligament cells by paracrine and autocrine functions in vivo. Endothelial cells also express NGF and trkA. Therefore, NGF may regulate functions of periodontal ligament cells and endothelial cells during periodontal tissue regeneration.Methods: Effects of NGF on expressions of bone/cementum‐related proteins (osteocalcin [OC], bone sialoprotein [BSP], bone morphogenetic protein [BMP‐7], core binding factor alpha [Cbfa‐1], and type I collagen), calcification in HPL cells, and proliferation and mRNA expression of vascular endothelial growth factor (VEGF), an endothelial cell mitogen, in human microvascular endothelial cells (HMVECs) were examined.Results: NGF elevated mRNA levels of OC, BSP, BMP‐7, Cbfa‐1, and type I collagen and enhanced mineral deposition in cultures of HPL cells. Furthermore, NGF stimulated mRNA expressions of VEGF‐A and VEGF‐B and cell proliferation in HMVEC.Conclusion: These findings suggest that the functional regulation of periodontal ligament cells and endothelial cells by NGF might result in the acceleration of periodontal tissue regeneration in vivo.
Cyclosporin‐Induced Downregulation of the Expression of E‐Cadherin During Proliferation of Edentulous Gingival Epithelium in Rats
Authors: Tu Hsiao‐Pei , Chen Yen‐Teen , Shieh Yi‐Shing , Huang Ren‐Yeong , Chin Yu‐Tang , Yang Shih‐Fang , Gau Ching‐Hwa , Fu Earl 
Published: May 2006

Background: To examine the role of E‐cadherin in epithelial hyperplasia of cyclosporin A (CsA)‐induced gingival enlargement, mRNA and protein levels of E‐cadherin, β‐catenin, proliferating cell nuclear antigen (PCNA), and Cyclin D1 were examined in the edentulous gingiva of rats following CsA treatment.Methods: Three weeks after the extraction of all maxillary molars, 20 male Sprague‐Dawley rats were assigned to a CsA‐fed group (30 mg/kg daily) or a control group. Five rats per group were sacrificed at weeks 1 and 4. Edentulous ridge specimens were taken, and the expression levels of E‐cadherin, β‐catenin, Cyclin D1, and PCNA mRNAs were estimated by reverse transcription‐polymerase chain reaction (RT‐PCR). Tissue specimens of the week 4 groups were examined using immunohistochemical (IHC) staining for proteins.Results: The mRNA expression of E‐cadherin was significantly weaker in the CsA‐treated group than the control group at both times. Using IHC staining, a weaker level of membrane‐bonded E‐cadherin was also observed in the gingival epithelial cells in the CsA group than in controls. By contrast, significantly stronger β‐catenin and Cyclin D1 mRNA expressions and protein levels were found in CsA‐treated rats than controls by RT‐PCR and immunohistochemistry at week 4, whereas PCNA production was stronger at both times.Conclusions: CsA treatment reduced the production of E‐cadherin but increased the production of β‐catenin, Cyclin D1, and PCNA. Thus, CsA may downregulate E‐cadherin gene expression, leading to the epithelial cell proliferation of gingival overgrowth.
Fast‐scale bifurcation in power‐factor‐correction buck‐boost converters and effects of incompatible periodicities
Authors: Zou Jianlong , Ma Xikui , Tse Chi K. , Dai Dong 
Published: May 2006

AbstractIn this paper, we derive the discrete‐time model for the power‐factor‐correction (PFC) buck‐boost converter in terms of a stroboscopic switching map. Fast‐scale instability is analysed through a fold diagram, which exposes the periodicity of the operation as well as the locations of the critical phase angles of the line voltage at which instability begins to occur along a half‐line cycle. The asymmetrical locations of the critical phase angles along a half‐line cycle is explained in terms of ‘under‐developed’ bifurcation. Border collision bifurcations are observed and analysed in detail. Copyright © 2006 John Wiley & Sons, Ltd.
Iminodiacetic acid derivatized porous silicon as a matrix support for sample pretreatment and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry analysis
Authors: Xu Songyun , Zhou Houjiang , Pan Chensong , Fu Yu , Zhang Yu , Li Xin , Ye Mingliang , Zou Hanfa 
Published: May 2006

AbstractIminodiacetic acid (IDA)‐1,2‐epoxy‐9‐decene has been synthesized and covalently linked to the surface of porous silicon wafer through a photochemical reaction. The negatively charged carboxylic acid groups on the porous silicon wafer are capable of binding oppositely charged species from sample solutions through electrostatic interactions. This allows the removal of contaminants prior to matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) by simply washing the porous silicon surface. The carboxylic acid end groups on porous silicon can be used to selectively bind and concentrate target species in sample solutions. Furthermore, Fe3+‐IDA‐derivatized porous silicon was prepared to specifically and effectively concentrate phosphopeptides from the tryptic digests of phosphoproteins, followed by MALDI‐MS analysis. Copyright © 2006 John Wiley & Sons, Ltd.
Chemical study of triterpenoid resinous materials in archaeological findings by means of direct exposure electron ionisation mass spectrometry and gas chromatography/mass spectrometry
Authors: Modugno Francesca , Ribechini Erika , Colombini Maria Perla 
Published: May 2006

AbstractA systematic study of standard triterpenes (α‐amyrine, oleanolic acid, betulin, lupeol, betulinic acid and lupenone) and of raw resinous materials (frankincense resin, mastic resin and birch bark pitch) was performed using direct exposure electron ionisation mass spectrometry (DE‐MS) and gas chromatography/mass spectrometry (GC/MS). DE‐MS provides a mass spectral fingerprint of organic materials in a few minutes which highlights the compounds that are the main components in the sample. The application of principal component analysis (PCA) on DE‐MS data in the mass ranges m/z 181–260 and m/z 331–500, corresponding to the fragmentation of triterpenoid molecules, enabled us to distinguish between different triterpenoid materials such as mastic resin, frankincense resin and birch bark pitch, and to graphically plot the resinous substances in three separate clusters, retaining 89% of the total variance. GC/MS analysis of the same materials has permitted us to elucidate in detail the molecular composition and to identify minor components and species that act as markers of the degradation undergone by the materials. The paper also reports the results for the organic residues contained in an Egyptian censer (5th–7th century AD) which was recovered in the excavation of the Necropolis of Antinoe (Egypt), and for the hafting material found on a Palaeolithic tool recovered at the site of Campitello (Arezzo, Tuscany), dating back to the Mid‐Pleistocene period. Although DE‐MS was found to be a fast analytical tool, it failed to give any information on the presence of less abundant compounds when applied to mixtures of different materials: only mastic resin was found in the residues from the Roman censer, whereas GC/MS analysis identified the presence of a vegetable oil from Brassicaceae seeds and Pinaceae resin. Birch bark pitch as a pure material was identified in the sample from the Palaeolithic flint flake using both procedures. Copyright © 2006 John Wiley & Sons, Ltd.
Mass spectrometry of proton adducts of fucosylated N‐glycans: fucose transfer between antennae gives rise to misleading fragments
Authors: Wuhrer Manfred , Koeleman Carolien A. M. , Hokke Cornelis H. , Deelder André M. 
Published: May 2006

AbstractFragmentation behavior of fucosylated N‐glycans in both protonated and sodiated form was studied by low‐energy collision‐induced dissociation with an ion trap mass spectrometer as well as by laser‐induced dissociation with matrix‐assisted laser desorption/ionization tandem time‐of‐flight mass spectrometry (MALDI‐TOF/TOF‐MS). Diantennary, core‐(α1–6)‐fucosylated N‐glycans with Lewis X (Gal(β1–4)[Fuc(α1–3)]GlcNAcβ1‐) and/or fucosylated LacdiNAc antennae (GalNAc(β1–4)[Fuc(α1–3)]GlcNAcβ1‐) were obtained from the human parasite Schistosoma mansoni and used as model substances, after labeling with 2‐aminobenzamide, or as native reducing glycans. While fragment spectra of sodiated as well as protonated species obtained in both mass spectrometers resulted in B‐ and Y‐type ions, fragmentation of proton adducts additionally gave rise to various fragment ions which had acquired fucose residues from other parts of the molecule. In particular, fucose was transferred efficiently to the Lewis X antennae suggesting the occurrence of difucosylated antennae, which could erroneously be interpreted as Lewis Y epitopes. By studying two additional model substances, this fucose gain was shown to occur by transfer of fucose between the antennae, but not by transfer of a core‐(α1–6)‐fucose. Despite the drastically different lifetimes of the ions, protonated species analyzed on the ion trap (millisecond range) and by MALDI‐TOF/TOF‐MS (microsecond range) showed similar rearrangement patterns, suggesting that the fucose mobility goes hand in hand with decomposition. Notably, permethylation of the model N‐glycans seemed to completely preclude fucose migration. This study indicates that caution should be applied with the interpretation of tandem mass spectrometric (MS/MS) data of protonated glycoconjugates, including glycopeptides, because of the potential occurrence of fucose rearrangements. Copyright © 2006 John Wiley & Sons, Ltd.
The Larynxane ST® intralaryngeal endoprosthesis for laryngotracheal pathologies
Authors: Chambres O , Schultz P , Debry C 
Published: May 2006

Objectives: The authors present their experience of a new intralaryngeal silicone prosthesis used to manage laryngotracheal pathologies associated with severe deglutition and respiratory disorders.Study design: This retrospective study, conducted in the head and neck surgery department of the Strasbourg University Hospital, France, included 10 patients (12 prostheses inserted) and was conducted from November 2000 to November 2003.Methods: A pre-operative clinical examination and a computed tomography and/or magnetic resonance scan assessed patients' laryngeal function. Two different semirigid laryngotracheal prostheses were used, inserted under general anaesthetic into the region from the supraglottic area to the first tracheal cartilages including the vocal folds and the ventricles. In group one (n = 5), patients presented with laryngeal stenosis with preserved deglutition function, and patent prostheses were used to restore laryngeal patency. In group two (n = 5), patients suffered from severe deglutition disorders and were in poor general condition and so required a cuffed tracheostomy tube, therefore obstructed prostheses were inserted to stop aspirations and to suppress the cuff of the tracheostomy tube. The study was performed under the authorization of the Biomedical Research Patients' Protection Committee of Alsace I, France.Results: The mean implantation duration was six months. The prosthesis used in the first group restored laryngeal patency without further complications such as aspiration or prosthesis (mucous) obstruction. The prosthesis used in group two prevented aspiration and allowed to change a cuff by an uncuffed tracheostomy tube.Conclusions: The intralaryngeal prosthesis used in group one constituted a reversible and effective method of treating laryngotracheal stenoses. The intralaryngeal prosthesis used in group two constituted an alternative to classical larynx exclusion techniques. The insertion is performed in few minutes under general anaesthetic through an endoscopic procedure. This reversible technique aimed to treat patients rapidly to reduce complications and post-operative morbidity.
Changes in expression of p53, proliferating cell nuclear antigen and bcl-2 in recurrent laryngeal cancer after radiotherapy
Authors: Lee B-J , Wang S-G , Roh H-J , Goh E-K , Chon K-M , Park D-Y 
Published: May 2006

The biological changes in recurrent laryngeal cancer following radiotherapy are not fully understood. The authors investigated differences in the expression of p53, proliferating cell nuclear antigen (PCNA) and bcl-2 in laryngeal cancer specimens before radiotherapy and in recurrent laryngeal cancer specimens following radiotherapy in the same patients. The authors investigated the expression of p53, PCNA and bcl-2 by immunohistochemical stain in 30 specimens from 15 patients with primary laryngeal cancer and recurrent laryngeal cancer after radiotherapy.The expression of p53 protein was significantly different in laryngeal cancer before radiotherapy (4/15, 26.7 per cent) compared with recurrent laryngeal cancer after radiotherapy (8/15, 53.3 per cent) (p < 0.05). The PCNA index was also significantly different in laryngeal cancer specimens before radiotherapy (mean, 11.9 per cent) compared with recurrent laryngeal cancer after radiotherapy (mean, 18.0 per cent) (p < 0.05). However, there was no statistically significant alteration of bcl-2 expression in primary compared with recurrent laryngeal cancer. The expression of p53 and PCNA increased in recurrent laryngeal cancers after radiotherapy, compared with that in laryngeal cancers before radiotherapy. Recurrent laryngeal cancers arising following radiotherapy became biologically aggressive.
Characteristics of primiparous women who are not reached by parental education classes after childbirth in Sweden
Authors: Fabian Helena M. , Rådestad Ingela J. , Waldenström Ulla 
Published: May 2006

Abstract Background: Parental education classes are part of the national child health promotion programme of the Swedish Child Health Clinics (CHC). Aim: To investigate attendance at parental education classes during the infant's first year, and to identify factors associated with non‐attendance in primiparous women. Methods: Swedish‐speaking women were recruited from 97% of all antenatal clinics in Sweden during 3 wk, evenly spread over 1 y from 1999 to 2000. Questionnaires were mailed in early pregnancy, and at 2 mo and 1 y after the birth. Two thousand, four hundred and forty women answered the main outcome question about class attendance asked in the third questionnaire, and 1076 of these were first‐time mothers. Results: Seventy‐eight per cent of the primiparas attended classes and 31% of the multiparas. Factors associated with non‐attendance in primiparas were: native language other than Swedish, a low level of education, smoking during pregnancy, inconvenient timing of pregnancy, feelings of loneliness and isolation, maternal hospital admission, and infant health problems. Three per cent of the primiparas did not attend classes either during pregnancy or after the birth, and this group seemed to constitute an even less privileged group. Conclusion: Parental education classes organized by the CHCs did not reach women who were more disadvantaged in terms of socio‐demographic background, maternal and infant health, and social network.
Glu257 in GroEL is a sensor involved in coupling polypeptide substrate binding to stimulation of ATP hydrolysis
Authors: Danziger Oded , Shimon Liat , Horovitz Amnon 
Published: May 2006

AbstractThe ATPase activity of many types of molecular chaperones is stimulated by polypeptide substrate binding via molecular mechanisms that are, for the most part, unknown. Here, we report that such stimulation of the ATPase activity of GroEL is abolished when its conserved apical domain residue Glu257 is replaced by alanine. This mutation is also found to convert the ATPase profile of GroEL, a group I chaperonin, into one that is characteristic of group II chaperonins. Steady‐state and transient kinetic analysis indicate that both effects are due, at least in part, to a reduction of the affinity of GroEL for ADP. This finding indicates that nonfolded proteins stimulate ATP hydrolysis by accelerating the off‐rate of the ADP formed, thereby allowing more rapid cycles of ATP binding and hydrolysis.
Identification of a new allele, HLA‐DRB5*0113, through three different molecular biology techniques†
Authors: Garino E. , Berrino M. , Bertinetto F. , Caropreso P. , Chidichimo R. , Dametto E. , Fasano M. E. , Frisaldi E. , Mazzola G. , Tondat F. , Boccadoro M. , Bruno B. , Amoroso A. 
Published: May 2006

AbstractA new HLA‐DRB5 allele, HLA‐DRB5*0113, has been identified in an Italian patient during routine HLA typing in order to activate a bone marrow donor search. HLA typing was performed by different molecular biology techniques, and the results showed that the HLA‐DRB5*0113 allele differs from HLA‐DRB5*010101 allele for three nucleotide substitutions at codons 57 (GAC→GAT; Asp) and 58 (GCT→GAG; Ala→Glu) of exon 2.
Blockade of the translocation and activation of mitogen‐activated protein kinase kinase 4 (MKK4) signaling attenuates neuronal damage during later ischemia–reperfusion
Authors: Zhang Qing‐Xiu , Pei Dong‐Sheng , Guan Qiu‐Hua , Sun Ya‐Feng , Liu Xiao‐Mei , Zhang Guang‐Yi 
Published: May 2006

AbstractMitogen‐activated protein kinase kinase 4 (MKK4), as an upstream activator of c‐Jun NH2‐terminal kinase (JNK), plays a critical role in response to cellular stresses and pro‐inflammatory cytokines. In this study, we investigated the subcellular localization and activation of MKK4 in response to global cerebral ischemia. Our results indicated that MKK4 had two activation peaks in both the cytosol and the nucleus, and translocated from the cytosol to the nucleus at 30 min and 6 h of reperfusion. We also detected the interaction of JNK‐interacting protein 3 (JIP3) and MKK4, which reached a maximum at 6 h of reperfusion. To elucidate the mechanism of translocation and activation, we administered N‐acetylcysteine, an antioxidant reagent, and a glutamate receptor 6 C‐terminus‐containing peptide (Tat‐GluR6‐9c) to rats. The data showed that N‐acetylcysteine limited the translocation and activation at 30 min of reperfusion; however, the peptide perturbed the subcellular localization and activation at 6 h of reperfusion, and subsequently provided a protective role against delayed neuronal cell death. Taken together, these results demonstrate that the translocation and activation of MKK4 during early reperfusion are closely associated with reactive oxygen species, whereas, at late reperfusion, MKK4 activation may be involved in brain ischemic injury.
Two‐stage metamorphic evolution of the Bemarivo Belt of northern Madagascar: constraints from reaction textures and in situ monazite dating
Authors: JÖNS N. , SCHENK V. , APPEL P. , RAZAKAMANANA T. 
Published: May 2006

AbstractNew results on the pressure–temperature–time evolution, deduced from conventional geothermobarometry and in situ U‐Th‐total Pb dating of monazite, are presented for the Bemarivo Belt in northern Madagascar. The belt is subdivided into a northern part consisting of low‐grade metamorphic epicontinental series and a southern part made up of granulite facies metapelites. The prograde metamorphic stage of the latter unit is preserved by kyanite inclusions in garnet, which is in agreement with results of the garnet (core)‐alumosilicate‐quartz‐plagioclase (inclusions in garnet; GASP) equilibrium. The peak metamorphic stage is characterized by ultrahigh temperatures of ∼900–950 °C and pressures of ∼9 kbar, deduced from GASP equilibria and feldspar thermometry. In proximity to charnockite bodies, garnet‐sillimanite‐bearing metapelites contain aluminous orthopyroxene (max. 8.0 wt% Al2O3) pointing to even higher temperatures of ∼970 °C. Peak metamorphism is followed by near‐isothermal decompression to pressures of 5–7 kbar and subsequent near‐isobaric cooling, which is demonstrated by the extensive late‐stage formation of cordierite around garnet. Internal textures and differences in chemistry of metapelitic monazite point to a polyphasic growth history. Monazite with magmatically zoned cores is rarely preserved, and gives an age of c. 737 ± 19 Ma, interpreted as the maximum age of sedimentation. Two metamorphic stages are dated: M1 monazite cores range from 563 ± 28 Ma to 532 ± 23 Ma, representing the collisional event, and M2 monazite rims (521 ± 25 Ma to 513 ± 14 Ma), interpreted as grown during peak metamorphic temperatures. These are among the youngest ages reported for high‐grade metamorphism in Madagascar, and are supposed to reflect the Pan‐African attachment of the Bemarivo Belt to the Gondwana supercontinent during its final amalgamation stage. In the course of this, the southern Bemarivo Belt was buried to a depth of >25 km. Approximately 25–30 Myr later, the rocks underwent heating, interpreted to be due to magmatic underplating, and uplift. Presumably, the northern part of the belt was also affected by this tectonism, but buried to a lower depth, and therefore metamorphosed to lower grades.