bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hepatitis B virus X protein affects S phase progression leading to chromosome segregation defects by binding to damaged DNA binding protein 1
Authors: Martin-Lluesma Silvia , Schaeffer Céline , Robert Eva Isabelle , van Breugel Pieter Cornelis , Leupin Olivier , Hantz Olivier , Strubin Michel 
Published: July 2008

Abstract

Chronic hepatitis B virus (HBV) infection is a leading cause of hepatocellular carcinoma (HCC), but its role in the transformation process remains unclear. HBV encodes a small protein, known as HBx, which is required for infection and has been implicated in hepatocarcinogenesis. Here we show that HBx induces lagging chromosomes during mitosis, which in turn leads to formation of aberrant mitotic spindles and multinucleated cells. These effects require the binding of HBx to UV-damaged DNA binding protein 1 (DDB1), a protein involved in DNA repair and cell cycle regulation, and are unexpectedly attributable to HBx interfering with S-phase progression and not directly with mitotic events. HBx also affects S-phase and induces lagging chromosomes when expressed from its natural viral context and, consequently, exhibits deleterious activities in dividing, but not quiescent, hepatoma cells.

Conclusion:

In addition to its reported role in promoting HBV replication, the binding of HBx to DDB1 may induce genetic instability in regenerating hepatocytes and thereby contribute to HCC development, thus making this HBV–host protein interaction an attractive target for new therapeutic intervention. (Hepatology 2008.)
Reducing risk of shortages due to drought in water supply systems using genetic algorithms
Authors: Nicolosi V. , Cancelliere A. , Rossi G. 
Published: July 2008

AbstractThe evaluation of risk of shortages due to drought in water supply systems is a necessary step both in the planning and in the operation stage. A methodology for unconditional (planning) and conditional (operation) risk evaluation is presented in this study. The risk evaluation is carried out by means of an optimisation model based on genetic algorithms aimed to define thresholds for the implementation of mitigation measures tested through Monte Carlo simulation that makes use of a stochastic generation of streamflows. The GA enables the optimisation of reservoir storages which identify monthly thresholds for shifting three states of the system (normal, alert and alarm) to which correspond different mitigation measures such as water demand rationing, additional supplies from alternative sources or reduction of release for ecological use. For unconditional risk evaluation a long time horizon has been considered (40 years), while the conditional risk evaluation is performed on a short time horizon (2–3 months). Results of simulations have been studied by means of consolidated indices of performance and frequency analysis of shortages of a given entity corresponding to different planning/management policies. A multi‐use water system has been used as a case study including competing irrigation and industrial demands. Copyright © 2008 John Wiley & Sons, Ltd.
Simplified procedure for hydraulic design of small‐diameter plastic pipes
Authors: Yildirim Gürol 
Published: July 2008

AbstractA simple, direct and efficient semi‐theoretical approach was developed to solve the hydraulic design problem of a horizontal or uphill sloping, single‐diameter multi‐outlet pipe. The proposed simplified model is essentially a design concept ensuring the hydraulic criteria for desired level of water application uniformity and allowable pressure head variation along with the limitation for economical pipe design. In the present technique, one can directly determine the smallest pipe size, pipe length, operating inlet pressure head and corresponding design parameters (pressure head variation, downstream end pressure head, total or friction losses and alternate uniformity expressions) for a desired level of water application uniformity with known design variables. For practical purposes, the design charts were also prepared to quickly determine the required design parameters. A comprehensive comparison test was applied for various design combinations. The examination results reveal that the proposed design technique is sufficiently accurate in comparison with the previous analytical and numerical procedures. Copyright © 2008 John Wiley & Sons, Ltd.
Effects of inhaled monoethanolamine on bronchoconstriction
Authors: Kamijo Y. , Hayashi I. , Ide A. , Yoshimura K. , Soma K. , Majima M. 
Published: July 2008

AbstractWe previously reported a 65‐year‐old man who aspirated an alkaline detergent containing 3.3% w/v (weight of solute per volume of solution) monoethanolamine (MEA) into his lungs, causing asthma‐like symptoms. We presently describe the mechanism of MEA‐induced bronchoconstriction according to findings in guinea pigs. In anesthetized, artificially ventilated animals, changes in airway opening pressure (Pao) were measured as an index of bronchoconstriction. An aerosol of 3.3% MEA solution (0.1 ml kg−1) inhaled through a tracheal cannula induced significantly stronger bronchoconstriction than an aerosol of potassium hydroxide (KOH) solution (0.1 ml kg−1) at the same pH. MEA‐induced bronchoconstriction was significantly suppressed by premedication with intravenously injected atropine sulfate (3 mg kg−1), a muscarinic receptor antagonist, or diphenhydramine hydrochloride (10 mg kg−1), a histamine‐H1receptor antagonist. MEA‐induced bronchoconstriction was not enhanced by premedication with an intravenous injection of neostigmine (0.1 mg kg−1), an acetylcholinesterase inhibitor. When bronchoconstriction was induced by MEA, histamine concentrations in bronchoalveolar lavage fluid (BALF) were not significantly greater than in BALF after KOH‐induced bronchoconstriction or in BALF after inhalation of physiologic saline.In vitro, contraction of trachea denuded of epithelium during superfusion with MEA (10 mm) was suppressed by premedication with pyrilamine maleate, a histamine‐H1receptor antagonist, at 10 and 100 µm. Contraction of trachea denuded of epithelium during superfusion with MEA (10 mm) was suppressed by premedication with atropine sulfate at 10 and 100 µm. These results suggest that asthma‐like symptoms may result partly from agonistic MEA effects at histamine‐H1receptors and muscarinic receptors. Copyright © 2008 John Wiley & Sons, Ltd.
Tracking bio‐molecules in live cells using quantum dots
Authors: Chang Yun‐Pei , Pinaud Fabien , Antelman Joshua , Weiss Shimon 
Published: July 2008

AbstractSingle particle tracking (SPT) techniques were developed to explore bio‐molecules dynamics in live cells at single molecule sensitivity and nanometer spatial resolution. Recent developments in quantum dots (Qdots) surface coating and bio‐conjugation schemes have made them most suitable probes for live cell applications. Here we review recent advancements in using quantum dots as SPT probes for live cell experiments. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Enhanced bone morphogenetic protein‐2 performance on hydroxyapatite ceramic surfaces
Authors: Schuessele A. , Mayr H. , Tessmar J. , Goepferich A. 
Published: July 2008

AbstractThe immobilization of biomolecules on biomaterial surfaces allows for the control of their localization and retention. In numerous studies, proteins have been simply adsorbed to enhance the biological performance of various materials in vivo. We investigated the potential of surface modification techniques on hydroxyapatite (HA) ceramic discs in an in vitro approach. A novel method for protein immobilization was evaluated using the aminobisphosphonates pamidronate and alendronate, which are strong Ca chelating agents, and was compared with the established silanization technique. Lysozyme and bone morphogenetic protein‐2 (BMP‐2) were used to assess the suitability of the two surface modification methods with regard to the enzymatic activity of lysozyme and to the capacity of BMP‐2 to stimulate the osteoblastic differentiation of C2C12 mouse myoblasts. After immobilization, a 2.5‐fold increase in enzymatic activity of lysozyme wasobserved compared with the control. The alkaline phosphatase activity per cell stimulated by immobilized BMP‐2 was 2.5‐fold higher [9 × 10−6 I.U.] than the growth factor on unmodified surfaces [2–4 × 10−6 I.U.]. With regard to the increase in protein activity, both procedures lead to equivalent results. Thus, the bisphosphonate‐based surface modification represents a safe and easy alternative for the attachment of proteins to HA surfaces. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Development of biodegradable and injectable macromers based on poly(ethylene glycol) and diacid monomers
Authors: Kim Jinku , Yaszemski Michael J. , Lu Lichun 
Published: July 2008

AbstractNovel biodegradable injectable poly(ethylene glycol)‐(PEG) based macromers were synthesized by reacting low‐molecular weight PEG (MW: 200) and dicarboxylic acids such as sebacic acid or terephthalic acid. Chemical structures of the resulting polymers were confirmed by Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy characterizations. Differential scanning calorimetry (DSC) showed that these polymers were completely amorphous above room temperature. After photopolymerization, dynamic elastic shear modulus of the crosslinked polymers was up to 1.5 MPa and compressive modulus was up to 2.2 MPa depending on the polymer composition. The in vitro degradation study showed that mass losses of these polymers were gradually decreased over 23 weeks of period in simulated body fluid. By incorporating up to 30 wt % of 2‐hydroxyethyl methylmethacrylate (HEMA) into the crosslinking network, the dynamic elastic modulus and compressive modulus was significantly increased up to 7.2 and 3.2 MPa, respectively. HEMA incorporation also accelerated the degradation as indicated by substantially higher mass loss of up to 27% after 20 weeks of incubation. Cytocompatability studies using osteoblasts and neural cells revealed that cell metabolic activity on these polymers with or without HEMA was close to the control tissue culture polystyrene. The PEG‐based macromers developed in this study may be useful as scaffolds or cell carriers for tissue engineering applications. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
Differential adhesion of Streptococcus gordonii to anatase and rutile titanium dioxide surfaces with and without functionalization with chlorhexidine
Authors: Barbour Michele E. , Gandhi Nikhil , el‐Turki Adel , O'Sullivan Dominic J. , Jagger Daryll C 
Published: July 2008

AbstractThe majority of dental implants are composed primarily of titanium and have an outer layer of titanium dioxide. Crystalline titanium dioxide most commonly exists in one of the two structures, anatase and rutile, and both of these have been observed on commercially available dental implants. Early implant failure can be associated with postoperative infection due to implant contamination during or immediately after surgery. The impetus of this study was to investigate whether functionalization of anatase and rutile titanium dioxide surfaces with chlorhexidine‐reduced subsequent colonization of the surface by Streptococcus gordonii. Exposure to 100 mg·L−1 chlorhexidine for 60 s resulted in a fivefold reduction in S. gordonii coverage on anatase and a twofold reduction on rutile. This may be related to a preferential adsorption of chlorhexidine to anatase compared with rutile. The reduction in bacterial coverage was not due to desorption of chlorhexidine into solution. More bacteria were observed on anatase than rutile surfaces without chlorhexidine functionalization, indicating that crystal structure may have a significant effect on bacterial colonization. In conclusion, functionalization with chlorhexidine reduced bacterial coverage on titanium dioxide surfaces, and anatase surfaces may be more amenable to such treatment than rutile. © 2008 Wiley Periodicals, Inc. J Biomed Mater Res, 2009
BASP1 in the lens
Authors: Bagchi M. , Kousis S. , Maisel H. 
Published: July 2008

AbstractBASP1 was detected in the embryonic and adult chicken lens, using immunological methods and by peptide sequence analysis. The protein was predominantly expressed in fiber cells and only faintly detected in annular pad cells. Localization of the protein was along the plasma membrane of fiber cells often in discrete areas. The role of BASP1 in the lens requires further study. J. Cell. Biochem. 105: 699–702, 2008. © 2008 Wiley‐Liss, Inc.
O‐acetylation of GD3 prevents its apoptotic effect and promotes survival of lymphoblasts in childhood acute lymphoblastic leukaemia
Authors: Mukherjee Kankana , Chava Anil Kumar , Mandal Chandan , Dey Sailendra Nath , Kniep Bernhard , Chandra Sarmila , Mandal Chitra 
Published: July 2008

AbstractWe have previously demonstrated induction of O‐acetylated sialoglycoproteins on lymphoblasts of childhood acute lymphoblastic leukaemia (ALL). These molecules promote survival of lymphoblasts by preventing apoptosis. Although O‐acetylated sialoglycoproteins are over expressed, the status of O‐acetylation of gangliosides and their role in lymphoblasts survival remains to be explored in ALL patients. Here, we have observed enhanced levels of 9‐O‐acetylated GD3 (9‐O‐AcGD3) in the lymphoblasts of patients and leukaemic cell line versus disialoganglioside GD3 in comparison to the normal cells. Localization of GD3 and 9‐O‐AcGD3 on mitochondria of patient's lymphoblasts has been demonstrated by immuno‐electron microscopy. The exogenous administration of GD3‐induced apoptosis in lymphoblasts as evident from the nuclear fragmentation and sub G0/G1 apoptotic peak. In contrast, 9‐O‐AcGD3 failed to induce such apoptosis. We further explored the mitochondria‐dependent pathway triggered during GD3‐induced apoptosis in lymphoblasts. GD3 caused a time‐dependent depolarization of mitochondrial membrane potential, release of cytochrome c and 7.4‐ and 8‐fold increased in caspase 9 and caspase 3 activity respectively. However, under identical conditions, an equimolar concentration of 9‐O‐AcGD3 failed to induce similar effects. Interestingly, 9‐O‐AcGD3 protected the lymphoblasts from GD3‐induced apoptosis when administered in equimolar concentrations simultaneously. In situ de‐O‐acetylation of 9‐O‐AcGD3 with sodium salicylate restores the GD3‐responsiveness to apoptotic signals. Although both GD3 and 9‐O‐acetyl GD3 localize to mitochondria, these two structurally related molecules may play different roles in ALL‐disease biology. Taken together, our results suggest that O‐acetylation of GD3, like that of O‐acetylated sialoglycoproteins, might be a general strategy adopted by leukaemic blasts towards survival in ALL. J. Cell. Biochem. 105: 724–734, 2008. © 2008 Wiley‐Liss, Inc.
Theoretical understanding on the v1‐SO band perturbed by the formation of magnesium sulfate ion pairs
Authors: Zhang Hao , Zhang Yun‐Hong , Wang Feng 
Published: July 2008

AbstractThe factors determining the spectroscopic characteristics of the v1‐SO42− band of the MgSO4 ion pairs are discussed via ab initio calculation, including coupling effect, hydrogen bonding effect, and direct contact effect of Mg2+ with SO42−. With the calculation of the heavy water hydrated contact ion pairs (CIP), the overlap between the librations of water and the v1‐SO42− band can be separated, and thus the coupling effect is abstracted, and this coupling effect leads to a blue shift for the v1‐SO42− band of 5.6 cm−1 in the monodentate CIP and 3.6 cm−1 in the bidentate CIP. The hydrogen bonding between each water molecule without relation to Mg2+ and the sulfate ion makes the v1‐SO42− band blue shift of 3.7 cm−1. When the outer‐sphere water around Mg2+ are hydrogen bonded between SO42− and Mg2+, it will make the largest disturbance to the v1‐SO42− band. Moreover, the inner‐sphere water can affect the v1‐SO42− band conjunct with the direct contact of Mg2+ with SO42−, showing a blue shift of 14.4 cm−1 in the solvent‐shared ion pair, 22.6 cm−1 in the monodentate CIP, 4.3 cm−1 in the bidentate CIP, and 21.4 cm−1 in the tridentate CIP. At last, the Raman spectral evolution in the efflorescence production process is tried to be rationalized. The shoulder at 995 cm−1 is attributed to the monodentate CIP with 2–3 outer‐sphere water molecules, whereas the new peak at 1021 cm−1 at high concentration is assigned to the formation of aqueous triple ion. © 2008 Wiley Periodicals, Inc. J Comput Chem, 2009
Contribution to the study of the vasculature of submandibular and sublingual glands and lymph nodes of rats by corrosion cast technique combined with scanning electron microscopy
Authors: Rossi‐Schneider Tíssiana Rachel , Verli Flaviana Dornela , Yurgel Liliane Soares , De Souza Maria Antonieta Lopes , Cherubini Karen 
Published: July 2008

AbstractThe study of anatomical structures in their normal state allows the identification of pathological changes that can occur in them. Angiogenesis and the vasculature have been widely studied, mainly because of their association with the development of neoplasms. One of the methods applied for such purposes is the corrosion cast technique, which provides a copy of the vessels with normal as well as pathological structures. The replica of the vasculature provided by this technique allows the three‐dimensional analysis of vessels by means of scanning electron microscopy. The aim of the present study was to demonstrate, by means of corrosion casts, the angioarchitecture of the submandibular and sublingual glands and lymph nodes. Scanning electron microscopy showed that the three structures have distinct vascular patterns. The corrosion cast technique can be employed in the study of the angioarchitecture of the submandibular and sublingual glands and lymph nodes, but requires specific precautions. The removal of the structures en bloc and the handling of the replicas with the aid of a stereoscopic magnifier reduce the risk of fractures. Microsc. Res. Tech., 2008. © 2008 Wiley‐Liss, Inc.
Occurrence of antennal glands in ants
Authors: Renthal Robert , Velasquez Daniel , Olmos David , Vinson S. Bradleigh 
Published: July 2008

AbstractA previous report of the discovery of exocrine glands in the antennal club of queens and workers of Solenopsis invicta Buren, 1972 left open the question of the extent to which similar glands occur in the Formicidae family. We wanted to know if these antennal glands are unique to Solenopsis, or they are found in a wider taxonomic group. Using scanning electron microscopy, we examined the antennae of 41 ant species. Presence of the antennal glands was indicated by a characteristic circumferential ring of pores in a distal antennal segment of workers. Pores were found in the 9th antennal segment of all 26 species of Solenopsis examined. Pores were absent in the following: Monomorium minimum, M. pharaonis, Pheidole sp., Crematogaster sp., Linepithema humile, Forelius sp., Dorymyrmex sp., Paratrechina sp., Oecophylla smaragdina, Campanotus sp., Ectatomma ruidum, E. tuberlatum, and Pseudomyrmex ferruginea. However, pores were found in the antennal club of Tetramorium bicarinatum workers and queens. After KOH digestion of T. bicarinatum antennae, internal canals were observed in both workers and queens, and the canals are connected to spherical reservoirs in queens. T. bicarinatum was the only non‐Solenopsis species examined, which showed evidence for antennal glands in the distal funiculus. Microsc. Res. Tech., 2008. © 2008 Wiley‐Liss, Inc.
Characterization of multimodal hydrophobic interaction chromatography media useful for isolation of green fluorescent proteins with small structural differences
Authors: Becker Kristian , Hallgren Elisabeth , Carredano Enrique , Palmgren Ronnie , Bülow Leif 
Published: July 2008

AbstractHydrophobic interaction chromatography (HIC) has been developed as a powerful technique for separating and purifying proteins. In this study, we have characterized the ability of new multimodal pH‐HIC media to resolve proteins with only small differences in their primary structures. This was done by determining the retention times of different green fluorescent protein (GFP) mutants prepared from Escherichia coli extracts. The mutants, modified with single or double hydrophobic amino acid substitutions in two positions, N212 and T230, could be resolved successfully, up to 2.1 column volumes in retention difference for single substitutions and 2.6 column volumes for double substitutions, at two pH and on two media with varying ligand density. The retention times also correlated well with calculated theoretical retentions (R2 = 0.91) using a hydrophobic descriptor. This medium can therefore be very useful in a final polishing step during purification and the protein library prepared represents a good screening set in validating and characterizing new future media due to the accessible, but yet, extremely small differences in protein structure. Copyright © 2008 John Wiley & Sons, Ltd.
Synthetic affinity ligands as a novel tool to improve protein stability
Authors: Sousa I. T. , Ruiu L. , Lowe C. R. , Taipa M. A. 
Published: July 2008

AbstractCutinase from Fusarium solani pisi is the model‐system for a new approach to assess and enhance protein stability based on the use of synthetic triazine‐scaffolded affinity ligands as a novel protein‐stabilizing tool. The active site of cutinase is excluded from the main surface regions postulated to be involved in early protein's thermal unfolding events. Hence, these regions are suitable targets for binding complementary affinity ligands with a potential stabilizing effect. A random solid‐phase combinatorial library of triazine‐bisubstituted molecules was screened for binding cutinase by a rapid fluorescence‐based method and affinity chromatography. The best binding substituents were combined with those previously selected by screening a rationally designed library. A second‐generation solid‐phase biased library was designed and synthesized, following a semi‐rational methodology. A dual screening of this library enabled the selection of ligands binding cutinase with higher affinity while retaining its functionality. These compounds were utilized for thermostability assessment with adsorbed cutinase at 60°C and pH 8.0. When bound to different types of ligands, the enzyme showed markedly distinct activity retention profiles, with some synthetic affinity ligands displaying a stabilizing effect on cutinase and others a clearly destabilizing effect, when compared with the free enzyme. Copyright © 2008 John Wiley & Sons, Ltd.
Identification of the promoter region and the 5′‐untranslated exons of the human voltage‐gated sodium channel Nav1.1 gene (SCN1A) and enhancement of gene expression by the 5′‐untranslated exons
Authors: Long Yue‐Sheng , Zhao Qi‐Hua , Su Tao , Cai Yang‐Lin , Zeng Yang , Shi Yi‐Wu , Yi Yong‐Hong , Chang Hao‐Hui , Liao Wei‐Ping 
Published: July 2008

AbstractVoltage‐gated sodium channels play critical roles in the excitability of the brain. A decreased level of Nav1.1 has been identified as the cause of severe myoclonic epilepsy in infancy. In the present study, we identified the transcription start site and three 5′‐untranslated exons of SCN1A by using 5′‐full RACE. The 2.5‐kb region upstream of the transcription start site was targeted as a potential location of the promoter. The 2.5‐kb genomic fragment (P2.5, from +26 to –2,500) and the 2.7‐kb fragment (P2.7, P2.5 combined with the 227‐bp 5′‐untranslated exons) were cloned to produce luciferase constructs. The P2.5 and the P2.7 drove luciferase gene expression in the human neuroblastoma cell line SH‐SY5Y but not in the human embryonic kidney cell line HEK‐293. The 5′‐untranslated exons could greatly enhance gene expression in SH‐SY5Y cells. The P2.7 could be used as a functional unit to study the role of SCN1A noncoding sequences in gene expression. These findings will also help in exploring the possibility of promoter mutant‐induced diseases and revealing the mechanism underlying the regulation of SCN1A expression in the normal brain. © 2008 Wiley‐Liss, Inc.