bluuebunny/crossref_metadata_2025_split huggingface dataset:
Increased HEXIM1 expression during erythroleukemia and neuroblastoma cell differentiation
Authors: Turano Mimmo , Napolitano Giuliana , Dulac Cyprien , Majello Barbara , Bensaude Olivier , Lania Luigi 
Published: October 2005

AbstractThe HEXIM1 protein, in association with 7SK snRNA, binds and inhibits the kinase activity of P‐TEFb (CDK9/cyclin T). P‐TEFb activity is crucial for efficient transcription elongation of viral and cellular genes. HEXIM1 was originally isolated as a protein up‐regulated by hexamethylene bisacetamide (HMBA), a prototypical inducer of differentiation. To determine the causative role of HEXIM1 during cell differentiation we analyzed the biochemical and functional consequences of HEXIM1 protein levels in several in vitro differentiation systems. We found that HEXIM1 mRNA and protein levels are up‐regulated during differentiation of murine erythroleukemia cells upon treatment with HMBA or DMSO. Stimulation of HEXIM1 is not restricted to hematopoietic cells, as induction of phenotypic differentiation of neuroblastoma cells by retinoic acid results in up‐regulation of HEXIM1. Moreover, ectopic expression of HEXIM1 causes growth inhibition and promotes neuronal differentiation. These findings highlight a crucial role of HEXIM1 protein during cell differentiation. © 2005 Wiley‐Liss, Inc.
p16INK4A and CDH13 hypermethylation in tumor and serum of non‐small cell lung cancer patients
Authors: Ulivi Paola , Zoli Wainer , Calistri Daniele , Fabbri Francesco , Tesei Anna , Rosetti Marco , Mengozzi Marta , Amadori Dino 
Published: October 2005

AbstractAberrant promoter hypermethylation of several known or putative tumor suppressor genes occurs frequently during the etiopathogenesis of lung cancer and is a promising tool for cancer detection. In the present study, promoter hypermethylation of p16INK4A and CDH13 genes was investigated in tumor tissue and in matched serum from 61 patients with histologically confirmed non‐small cell lung cancer. Using a fluorescence‐based method of methylation‐specific PCR (F‐MSP), methylation of p16INK4A and CDH13 was detected in 79% and 66% of tumors, respectively, and was not significantly related to conventional clinicopathological characteristics of patients or tumors. Methylation of both genes was observed in 52% of tumors and of at least one gene in 92% of lesions. In matched serum, hypermethylation of p16INK4A and CDH13 was observed in 26% and 23% of patients, respectively, but as they were not associated, the methylation of at least one gene was detected in 39% of patients. In conclusion, the frequency of p16INK4A or CDH13 hypermethylation in patient serum, together with evidence of their early occurrence in lung cancerogenesis and the total lack of methylation in serum from healthy individuals, offer a promising tool for non invasive early detection of lung cancer. © 2005 Wiley‐Liss, Inc.
Na+/K+/Cl− cotransporter activates MAP‐kinase cascade downstream to protein kinase C, and upstream to MEK
Authors: Panet Rivka , Eliash Michal , Atlan Henri 
Published: October 2005

AbstractIn this study, we demonstrated that the specific inhibitors of the Na+/K+/Cl− cotransporter (NKCC1), bumetanide and furosemide, inhibited extracellular regulated kinase (ERK) phosphorylation in Balb/c 3T3 fibroblasts, stimulated with a variety of mitogens. In addition to fibroblast growth factor (FGF) shown before, the various mitogens tested in the present study (endothelial growth factor (EGF), platelet‐derived growth factor (PDGF), insulin, thrombin, and the phorbol ester, 12‐O‐tetradecanoyl‐phorbol‐13‐acetate (TPA)). Enter, the Ras/Raf/MEK/ERK cascade via different growth factors receptors and through one of the two main routes. The results of the present study provide evidence that have led us to conclude that the target protein which is controlled by the Na+/K+/Cl− cotransporter, is downstream of tyrosine kinase receptors, as well as of the G‐protein‐coupled receptor (GPCR). Several additional lines of evidence supported the above conclusion: (i) furosemide inhibits phosphorylation of MAPK kinase (MEK) induced by receptor tyrosine kinase (RTK) ligands, such as PDGF, FGF, and EGF. (ii) Furosemide also inhibited ERK phosphorylation, induced by thrombin, a GPCR. (iii) Furosemide inhibited MEK and ERK phosphorylation even when ERK phosphorylation was induced by direct activation of protein kinase C (PKC) by TPA, which bypasses early steps of the mitogenic cascade. In addition, we found that furosemide did not affect PKC phosphorylation induced directly by TPA. Taken together, the results of the present study indicate that the signal transduction protein, controlled by the Na+/K+/Cl− cotransporter, must be downstream of the PKC, and at/or upstream to MEK in the Ras/Raf/MEK/ERK cascade. © 2005 Wiley‐Liss, Inc.
The N‐terminus of phosphoinositide 3‐kinase‐C2β regulates lipid kinase activity and binding to clathrin
Authors: Wheeler Matthew , Domin Jan 
Published: October 2005

AbstractThe class II phosphoinositide 3‐kinase (PI3K)‐C2β is recruited to polypeptide growth factor receptors following ligand stimulation. In contrast to the class I A p85/p110 heterodimers, this interaction is dependent upon proline residues present within the N‐terminal sequence of the 3‐phosphoinositide kinase. However, the mechanism by which PI3K‐C2β catalytic activity is regulated currently remains unknown. In many tumours, increased expression of ErbB receptors confers a poor prognosis. We demonstrate that increased expression of EGFR enhanced its association with PI3K‐C2β following stimulation with EGF. Deletion of the first proline rich region within the N‐terminus precluded recruitment of PI3K‐C2β to activated EGFR. Although deletion of the first proline rich motif also rendered the enzyme catalytically inactive, further deletions (residues 1–148 and 1–261) that removed the second and third proline rich motifs increased kinase activity. These data confirm a regulatory role for the N‐terminus of class II PI3K enzymes suggesting that catalytic activity is regulated by factors that associate with this region during recruitment to activated growth factor receptors. Using an N‐terminal PI3K‐C2β‐GST fusion protein, clathrin heavy chain was affinity purified from A431 cell lysates. Association of PI3K‐C2β with clathrin was confirmed by co‐immunoprecipitation from cell lysates while intracellular co‐localisation of PI3K‐C2β and clathrin was confirmed by confocal microscopy. Our findings demonstrate for the first time that the PI3K‐C2β isoform associates with clathrin and thus provides a link between receptor mediated intracellular signalling and clathrin coated vesicle transport. © 2005 Wiley‐Liss, Inc.
Proteasome subunit LMP2 is required for matrix metalloproteinase‐2 and ‐9 expression and activities in human invasive extravillous trophoblast cell line
Authors: Wang Hong‐Xing , Wang Hong‐Mei , Lin Hai‐Yan , Yang Qing , Zhang Heng , Tsang Benjamin K. , Zhu Cheng 
Published: October 2005

AbstractThe ubiquitin‐proteasome pathway (UPP) is involved in the degradation of the extracellular matrix (ECM) and trophoblastic invasion during early pregnancy. Our previous studies demonstrated that inhibition of UPP suppresses expression of matrix metalloproteinase (MMP)‐2 and ‐9. LMP2 is an important proteasome subunit that is critical for proteasome activity. This study investigated the regulatory mechanism of LMP2 on the expression and activities of MMP‐2 and MMP‐9. Our results showed that transfection of LMP2 siRNA plasmid into the human invasive extravillous trophoblast cell line (HTR8/Svneo) could significantly suppress expression of LMP2 mRNA and protein. The mRNA expression of MMP‐2 and MMP‐9 and their activities were markedly decreased in the LMP2‐inhibited cells. Inhibition of LMP2 could also reduce IκBα mRNA level, although the expression of phosphorylated IκBα was increased. In the LMP2‐inhibited cells, expression of mRNA encoding NF‐κB subunits p50 and p65 remained normal, but the p50 protein level was significantly decreased in the cytosolic and nuclear extracts, while p65 protein was markedly reduced only in the nuclear extract. We also demonstrated that blockage of the NF‐κB pathway by the NF‐κB translocation inhibitor SN50 markedly reduced the expression of MMP‐2 and MMP‐9 in HTR8/Svneo cells, a result that is fully consistent with the results from the LMP2‐inhibited HTR8/Svneo cells. These data suggest that LMP2 contributes to IκBα degradation and p50 generation, and that inhibition of LMP2 suppresses expression and activities of MMP‐2 and MMP‐9 by blocking the transfer of active NF‐κB heterodimers into the nucleus. © 2005 Wiley‐Liss, Inc.
Unique human CD133+ leukemia cell line and its modulation towards a mesenchymal phenotype by FGF2 and TGFβ1
Authors: Bodo Maria , Baroni Tiziano , Bellucci Catia , Lilli Cinzia , De Ioanni Maria , Bonifacio Elisabetta , Moretti Lorenzo , Becchetti Ennio , Bellocchio Silvia , Delfini Costante , Lumare Eleonora , Tabilio Antonio 
Published: October 2005

AbstractImmunological features of GM‐490 cells, a new blood cell line from a patient with acute lymphoblastic leukemia, included lack of CD34, CD38, CD45, CD14, HLA‐DR, and lymphoid and myeloid markers and expression of CD29, CD36, CD44, CD54, CD71, CD105, and CD133. Molecular analysis indicated CD45 gene expression was absent but CD34 mRNA was present. GM‐490 cells constitutively produced fibronectin (FN), type III and traces of type I collagen, collagenases, glycosaminoglycans (GAG) and biglycan and betaglycan proteoglycans (PG) as well as FGF2 and TGFβ1. When FGF2 and/or TGFβ1 were added to cells in vitro, they stimulated cell proliferation and differently modulated matrix production and growth factor receptor expression. Reverse transcription‐polymerase chain reaction (RT‐PCR) detection of transcripts encoding for osteocalcin and RUNX2 suggests GM‐490 cells differentiate towards the osteoblast pathway. GM‐490 cells expressed the low affinity nerve growth factor receptor (p75LNGFR), a somatic stem cell marker that is not detected in hematopoietic cells, leading to the hypothesis that GM‐490 has mesenchymal stem cell properties. The reciprocal modulating effects of FGF2 and TGFβ1 on each other's receptors make the GM‐490 cell line a new model for investigating the relationship between these growth factors and their receptors in autocrine loops which are believed to sustain the malignant clone in hematological diseases. © 2005 Wiley‐Liss, Inc.
Bulk versus surface contributions in nonlinear optics of isotropic centrosymmetric media
Authors: Cattaneo Stefano , Kauranen Martti 
Published: October 2005

AbstractThe relative importance of bulk and surface contributions to the second‐harmonic response of isotropic surfaces is addressed by studying the polarization properties of second‐harmonic signals generated by two noncollinear input beams. Measurements on an air‐glass interface reveal that the bulk contributions dominate in transmission but are negligible in reflection. Even when the nonlinear response has a bulk origin, it is strongly suppressed when the interaction volume is localized deep inside the bulk medium. Conversely, bulk contributions are maximized when the interaction volume is localized near the surface. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties of Si and Ge nanocrystals: Parameter‐free calculations
Authors: Ramos L. E. , Weissker H.‐Ch. , Furthmüller J. , Bechstedt F. 
Published: October 2005

AbstractAn overview is given on the electronic and optical properties of Si and Ge nanocrystals. We model free‐standing Si and Ge nanocrystals passivated with H, with up to 363 group‐IV atoms and 276 H and oxidized nanocrystals with additional silicon oxide shells, e.g. Si41(O60Si42)(O108Si64)H148. The results discussed are based on parameter‐free calculations for relaxed atomic structures. The electronic states and the many‐body effects are considered within the density‐functional theory and the supercell method. Energy gaps are described within the Kohn–Sham independent‐particle picture and within the independent‐quasiparticle picture, whereas electronic excitations are treated within the delta self‐consistent method by pair excitation energies. The projector‐augmented wave method allows the calculation of optical matrix elements, oscillator strengths, optical spectra, and radiative lifetimes. We discuss quantum confinement, structural relaxation, oxidation, and the role of defects in oxidized Si NCs. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Influence of quadratic contributions in magnetization‐induced second harmonic generation studies of magnetization reversal
Authors: Valev V. K. , Gruyters M. , Kirilyuk A. , Rasing Th. 
Published: October 2005

AbstractMagnetization‐induced optical Second Harmonic Generation (MSHG) from an exchange‐biased CoO/Fe multilayer produces an asymmetrical hysteresis loop that indicates different magnetization reversal behaviour between the interface and the bulk ferromagnet. A more careful analysis of the data demonstrates that this asymmetry is in fact due to a quadratic dependence on the magnetization of the MSHG intensity. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin–orbit effects on the optical anisotropy of semiconductor surfaces
Authors: Vázquez‐Nava R. A. , Mendoza B. S. , Arzate N. 
Published: October 2005

AbstractWe study the effects of spin–orbit (SO) coupling on the reflectance anisotropy spectroscopy of semiconductor surfaces. The sp3s* nearest‐neighbor tight‐binding model with allowance for SO interaction is used to obtain theoretical reflectance anisotropy spectra of clean (110)1 × 1 surfaces of III–V semiconductors. We compare our SO‐spectra with the experimental spectra and find good agreement between them. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Vascular Control during Hepatectomy: Review of Methods and Results
Authors: Smyrniotis Vassilios , Farantos Charalampos , Kostopanagiotou Georgia , Arkadopoulos Nikolaos 
Published: October 2005

AbstractThe various techniques of hepatic vascular control are presented, focusing on the indications and drawbacks of each. Retrospective and prospective clinical studies highlight aspects of the pathophysiology, indications, and morbidity of the various techniques of hepatic vascular control. Newer perspectives on the field emerge from the introduction of ischemic preconditioning and laparoscopic hepatectomy. A literature review based on computer searches in Index Medicus and PubMed focuses mainly on prospective studies comparing techniques and large retrospective ones. All methods of hepatic vascular control can be applied with minimal mortality by experienced surgeons and are effective for controlling bleeding. The Pringle maneuver is the oldest and simplest of these methods and is still favored by many surgeons. Intermittent application of the Pringle maneuver and hemihepatic occlusion or inflow occlusion with extraparenchymal control of major hepatic veins is particularly indicated for patients with abnormal parenchyma. Total hepatic vascular exclusion is associated with considerable morbidity and hemodynamic intolerance in 10% to 20% of patients. It is absolutely indicated only when extensive reconstruction of the inferior vena cava (IVC) is warranted. Major hepatic veins/ and limited IVC reconstruction has been also achieved under inflow occlusion with extraparenchymal control of major hepatic veins or even using the intermittent Pringle maneuver. Ischemic preconditioning is strongly recommended for patients younger than 60 years and those with steatotic livers. Each hepatic vascular control technique has its place in liver surgery, depending on tumor location, underlying liver disease, patient cardiovascular status, and, most important, the experience of the surgical and anesthesia team.
18F‐Fluorodeoxyglucose Positron Emission Tomography: Useful Technique for Predicting Malignant Potential of Gastrointestinal Stromal Tumors
Authors: Kamiyama Yoichi , Aihara Ryuusuke , Nakabayashi Toshihiro , Mochiki Erito , Asao Takayuki , Kuwano Hiroyuki , Oriuchi Nobuo , Endo Keigo 
Published: October 2005

AbstractThe malignant potential of gastrointestinal stromal tumors (GISTs) is difficult to diagnose before surgery because the diagnoses are based on tumor diameter and mitotic index. The progression of small GISTs is always observed because they do not seem to have malignant potential. 18F‐Fluorodeoxyglucose (FDG)‐positron emission tomography (PET) is a useful technique for assessing tumor activity. The objective of this study was to determine if FDG‐PET is useful for predicting the malignant potential of gastric GISTs. Ten patients diagnosed with gastric GISTs participated. FDG‐PET was performed on all of them before tumor resection. A whole‐body image was initiated 40 minutes after the injection of 275 to 370 MBq FDG. FDG uptake was assessed by a standardized uptake value. All tumors had FDG uptake. There was a significant correlation between the FDG uptake and both the Ki67 index and the mitotic index but not the tumor diameter. The FDG uptake and malignant potential of gastric GISTs had a significant correlation. FDG‐PET may be of considerable value for predicting the malignant potential of gastric GISTs before surgery. A gastric GIST with a high FDG uptake should be regarded as having malignant potential.
Effect of Neostigmine on Organ Injury in Murine Endotoxemia: Missing Facts about the Cholinergic Antiinflammatory Pathway
Authors: Akinci Seda B. , Ulu Nadir , Yondem Omer Z. , Firat Pinar , Guc M. Oguz , Kanbak Meral , Aypar Ulku 
Published: October 2005

AbstractElectrical and pharmacologic stimulation of the efferent cholinergic antiinflammatory pathway suppress the systemic inflammatory response and can prevent lethal endotoxemia. Neostigmine, a cholinergic agent, has not been tested to determine if it can prevent histopathologic organ injury in endotoxemia. In the present study, the effects of neostigmine treatment on the histopathologic organ injury inflicted byEscherichia coliendotoxin in a mouse model of septic shock was investigated. Endotoxemia in mice caused weight loss and increased spleen, liver, and lung weight. When the organs were examined for histopathologic injury, endotoxemia increased interstitial inflammation in the lungs, liver injury, and organ injury in general terms; neostigmine, at a dose of 0.1 mg/kg, failed to attenuate these effects. Although the simultaneous administration of neostigmine at a dose of 0.3 mg/kg and endotoxin decreased interstitial inflammation in the lungs, vacuolar degeneration in the liver, and total liver injury, mortality was increased with this dose in the presence of endotoxemia. We conclude that neostigmine at a dose of 0.1 mg/kg was not protective against histopathologic organ injury in mice with endotoxemia, and a higher dose (0.3 mg/kg) was not tolerated probably owing to nonspecific parasympathetic action including cardiovascular effects. Further studies are required to determine the contribution of sites in the cholinergic antiinflammatory pathway.
Surgical Treatment of Chronic Amebic Colitis
Authors: Ozdogan Mehmet , Baykal Atac , Kavuklu Burak , Aran Omer 
Published: October 2005

AbstractThere are limited data concerning the surgical management of chronic amebic colitis (CAC) in the literature. We present our experience with 10 patients with CAC treated surgically. Patients’ records were retrospectively analyzed for age, sex, duration of clinical manifestations, colonoscopic findings, the type of surgical operation, and the postoperative course. Total proctocolectomy and J‐pouch construction was performed in two patients who had CAC with severe rectal involvement. Total colectomy and the Hartmann procedure was performed in eight patients with mild to moderate rectal involvement. This treatment was successful in preserving the rectum in four of the eight. Our results suggest that rectal preservation can be a reliable treatment option in patients with CAC who have mild to moderate rectal involvement. Total proctocolectomy and ileoanal anastomosis with pouch construction should be the treatment of choice for patients with CAC who have severe rectal involvement.
Histological Grading in Gastric Cancer by Ming Classification: Correlation with Histopathological Subtypes, Metastasis, and Prognosis
Authors: Luebke Thomas , Baldus Stephan E. , Grass Guido , Bollschweiler Elfriede , Thiele Jürgen , Dienes Hans‐Peter , Hoelscher Arnulf H. , Moenig Stefan P. 
Published: October 2005

AbstractThe aim of this prospective study was to analyze Ming’s classification in correlation with other currently used classification systems of gastric cancer. In addition, we wanted to define the prognostic significance of the Ming classification system. The present study analyzed material of 117 patients with gastric carcinoma who underwent D2‐gastrectomy with curative intent. All specimens were catagorized according to International Union Against Cancer (UICC) classification, World Health Organization (WHO) classification, Borrmann classification, Laurén classification, Goseki classification, Ming classification, and tumor differentiation. For analysis of correlation between the classification systems, the correlation coefficient according to Spearman was calculated. The survival curves have been calculated according to the Kaplan‐Meier method. According to the Ming classification, 38.5% of the carcinomas exhibited an expanding growth pattern, and 61.5% of specimens showed an infiltrating growth pattern. The subtypes according to the Ming and Laurén classification correlated significantly (P < 0.001). WHO classification (P < 0.001), tumor differentiation (P < 0.001), and Goseki classification (P < 0.001), as well as the macroscopic classification of Borrmann (P < 0.001) and the pT and pN categories of the UICC classification exhibited a highly significant correlation with the Ming classification (P < 0.001 and 0.001, respectively). Median overall survival was 31.3 months. In Kaplan‐Meier analysis, the 3‐year survival rates were lower in the infiltrative tumor type when compared to the expansive tumor type according to Ming (P = 0.0847). In multivariate analysis, only the UICC system presented as an independent prognostic factor in multivariate analysis (P < 0.001). This study shows that the Ming classification correlates significantly with the currently used classification systems for gastric cancer and with the UICC staging system, especially, the pT and pN category. The 3‐year survival rates were lower in the infiltrative tumor type than in the expansive tumor type according to Ming. However, the Ming classification is not an independent prognostic factor.