bluuebunny/crossref_metadata_2025_split huggingface dataset:
Intracellular Ca2+stores are essential for injury induced Ca2+signaling and re‐endothelialization
Authors: Zhao Zhiqiang , Walczysko Petr , Zhao Min 
Published: October 2007

AbstractEndothelialization repairs the lining of damaged vasculature and is a key process in preventing thrombosis and restenosis. It has been demonstrated that extracellular calcium ([Ca2+]o) influx is important for subsequent endothelialization. The role of intracellular Ca2+stores in mechanical denudation induced intracellular calcium ([Ca2+]i) rise and endothelialization remains to be demonstrated. Using monolayer culture of a human endothelial cell line (human umbilical vein endothelial cell, HUVEC), we investigated [Ca2+]iwave propagation and re‐endothelialization following mechanical denudation. Consistent with previous reports for other types of cells, mechanical denudation induces calcium influx, which is essential for [Ca2+]irise and endothelialization. Moreover, we found that intracellular Ca2+stores are also essential for denudation induced [Ca2+]iwave initiation and propagation, and the subsequent endothelialization. Thapsigargin which depletes intracellular Ca2+stores completely abolished [Ca2+]iwave generation and endothelialization. Xestospongin C (XeC), which prevents Ca2+release from intracellular Ca2+stores by inhibition of inositol 1,4,5‐trisphosphate (IP3) receptor, inhibited intercellular Ca2+wave generation and endothelialization following denudation. Purinergic signaling through a suramin sensitive mechanism and gap junction communication also contribute to in intercellular Ca2+wave propagation and re‐endothelialization. We conclude that intracellular Ca2+stores, in addition to extracellular Ca2+, are essential for intracellular Ca2+signaling and subsequent endothelialization following mechanical denudation. J. Cell. Physiol. 214: 595–603, 2008. © 2007 Wiley‐Liss, Inc.
Sodium arsenite induces heat shock protein 70 expression and protects against secretagogue‐induced trypsinogen and NF‐κB activation
Authors: Bhagat Lakshmi , Singh Vijay P. , Dawra Rajinder K. , Saluja Ashok K. 
Published: October 2007

AbstractHeat shock proteins (HSPs), induced by a variety of stresses, are known to protect against cellular injury. Recent studies have demonstrated that prior β‐adrenergic stimulation as well as thermal or culture stress induces HSP70 expression and protects against cerulein‐induced pancreatitis. The goal of our current studies was to determine whether or not a non‐thermal, chemical stressor like sodium arsenite also upregulates HSP70 expression in the pancreas and prevents secretagogue‐induced trypsinogen and NF‐κB activation. We examined the effects of sodium arsenite preadministration on the parameters of cerulein‐induced pancreatitis in rats and then monitored the effects of preincubating pancreatic acini with sodium arsenite in vitro. Our results showed that sodium arsenite pretreatment induced HSP70 expression both in vitro and in vivo and significantly ameliorated the severity of cerulein‐induced pancreatitis, as evidenced by the markedly reduced degree of hyperamylasemia, pancreatic edema, and acinar cell necrosis. Sodium arsenite pretreatment not only inhibited trypsinogen activation and the subcellular redistribution of cathepsin B, but also prevented NF‐κB translocation to the nucleus by inhibiting the IκBα degradation both in vivo and in vitro. We also examined the effect of sodium arsenite pretreatment in a more severe model of pancreatitis induced by L‐arginine and found a similarly protective effect. Based on our observations we conclude that, like thermal stress, chemical stressors such as sodium arsenite also induce HSP70 expression in the pancreas and protect against acute pancreatitis. Thus, non‐thermal pharmacologically induced stress can help prevent or treat pancreatitis. J. Cell. Physiol. 215: 37–46, 2008. © 2007 Wiley‐Liss, Inc.
High glucose suppresses expression of equilibrative nucleoside transporter 1 (ENT1) in rat cardiac fibroblasts through a mechanism dependent on PKC‐ζ and MAP kinases
Authors: Grden Marzena , Podgorska Marzena , Kocbuch Katarzyna , Rzepko Robert , Szutowicz Andrzej , Pawelczyk Tadeusz 
Published: October 2007

AbstractRecently it was demonstrated that the elevated concentration of glucose but not lack of insulin is responsible for suppression of equilibrative nucleoside transporter (ENT1) in diabetic rat cardiac fibroblasts (CFs). The present study was undertaken to determine the signaling pathway utilized by glucose to regulate the expression of ENT1 in the primary culture of rat CFs. Pretreatment of CFs with Go 6983, an isozyme non‐selective PKC inhibitor, prevented the high glucose (25 mM) effect on ENT1 mRNA level and nitrobenzylthioinosine (NBTI)‐sensitive adenosine uptake. Similar effect was observed with a cell‐permeable PKC‐ζ pseudosubstrate, whereas Go 6976 a selective inhibitor of Ca2+‐dependent PKC‐α and PKC‐β isozymes had little effect on high glucose‐induced suppression of ENT1 mRNA level. Incubation of CFs with nitric oxide (NO) donors (SNAPE, SNP) or NO synthase inhibitors (L‐NAME, L‐NMMA) prior to exposition of CFs to high glucose did not change the glucose effect on ENT1 mRNA level. The high glucose‐induced suppression of ENT1 expression was blocked by PD9859 (an inhibitor of MEK), whereas neither wortmannin (an inhibitor of PI3K) nor rapamycin (an inhibitor of mTOR) affected the glucose action on ENT1 transcript level. Highly effective in preventing the high glucose effect on ENT1 mRNA level were GW 5074 (an inhibitor of Raf kinase) and SB 203580 (selective p38 MAPK inhibitor). These findings indicate that high glucose suppresses the expression of ENT1 in CFs by NO independent manner involving the signaling through PKC‐ζ, Raf‐1, MEK, and p38 MAPK pathways. J. Cell. Physiol. 215: 151–160, 2008. © 2007 Wiley‐Liss, Inc.
Regulation of human cripto‐1 gene expression by TGF‐β1 and BMP‐4 in embryonal and colon cancer cells
Authors: Mancino Mario , Strizzi Luigi , Wechselberger Christian , Watanabe Kazuhide , Gonzales Monica , Hamada Shin , Normanno Nicola , Salomon David S. , Bianco Caterina 
Published: October 2007

AbstractHuman Cripto‐1 (CR‐1) is a cell membrane protein that is overexpressed in several different types of human carcinomas. In the present study we investigated the mechanisms that regulate the expression of CR‐1 gene in cancer cells. We cloned a 2,481 bp 5′‐flanking region of the human CR‐1 gene into a luciferase reporter vector and transfected NTERA‐2 human embryonal carcinoma cells and LS174‐T colon cancer cells to test for promoter activity. Activity of CR‐1 promoter in both cell lines was modulated by two TGF‐β family members, TGF‐β1 and BMP‐4. In particular, TGF‐β1 significantly up‐regulated CR‐1 promoter activity, whereas a dramatic reduction in CR‐1 promoter activity was observed with BMP‐4 in NTERA‐2 and LS174‐T cells. Changes in the CR‐1 promoter activity following TGF‐β1 and BMP‐4 treatments correlated with changes in CR‐1 mRNA and protein expression in NTERA‐2 and LS174‐T cells. We also identified three Smad binding elements (SBEs) within the CR‐1 promoter and point mutation of SBE1 (−2,197/−2,189) significantly reduced response of the CR‐1 promoter to both TGF‐β1 and BMP‐4 in NTERA‐2 and LS174‐T cells. Chromatin immunoprecipitation assay also demonstrated binding of Smad‐4 to a CR‐1 promoter DNA sequence containing SBE1 in LS174‐T cells. Finally, BMP‐4 inhibited migration of LS174‐T cells and F9 mouse embryonal carcinoma cells by downregulation of CR‐1 protein. In conclusion, these results suggest a differential modulation of CR‐1 gene expression in embryonal and colon cancer cells by two different members of the TGF‐β family. J. Cell. Physiol. 215: 192–203, 2008. © 2007 Wiley‐Liss, Inc.
Ultrasound stimulates MMP‐13 expression through p38 and JNK pathway in osteoblasts
Authors: Chiu Yung‐Cheng , Huang Tsang‐Hai , Fu Wen‐Mei , Yang Rong‐Sen , Tang Chih‐Hsin 
Published: October 2007

AbstractIt has been shown that ultrasound (US) stimulation accelerates fracture healing, bone maturation, and remodeling in the animal models and in clinical studies. One of the major factor involves in remodeling process is matrix metalloproteinases (MMPs) such as MMP‐13 that has been shown to degrade the native interstitial collagens in several tissues. Here we found that US stimulation increased the secretion of MMP‐13 in cultured rat osteoblasts, as shown by zymographic analysis. US stimulation also increased the mRNA level of MMP‐13, c‐Fos, and c‐Jun. Cycloheximide (an inhibitor of protein translocation) and actinomycin D (an inhibitor of gene transcription) did not inhibit the MMP‐13, c‐Fos, and c‐Jun mRNA expression, suggesting that such expression does not require de novo protein synthesis and not change their stabilities. p38 inhibitor, SB203580 or JNK inhibitor, SP600125 but not ERK inhibitor, PD98059 attenuated the US‐induced MMP‐13, c‐Fos, and c‐Jun expression; these results were further substantiated by transfecting with the dominant negative mutants of p38 or JNK. The binding of c‐Fos and c‐Jun to the AP‐1 element on the MMP‐13 promoter and the enhancement of AP‐1 luciferase activity was enhanced by US stimulation. Taken together, our results provide evidence that US stimulation increases MMP‐13 expression through p38 and JNK signaling pathway to regulate bone remodeling. J. Cell. Physiol. 215: 356–365, 2008. © 2007 Wiley‐Liss, Inc.
Hydrolysis and solubilization of corn gluten by Neutrase
Authors: Kılıç Apar Dilek , Özbek Belma 
Published: October 2007

AbstractHydrolysis and solubilization of corn gluten were performed using a commercial protease preparation Neutrase. The effects of substrate concentration, enzyme concentration, temperature, pH and hydrolysate amount on the degree of hydrolysis and solubility of corn gluten were investigated depending on processing time. Trials were conducted in a batch reactor and degrees of hydrolysis were computed using a pH‐stat method. Results show that solubility and degree of hydrolysis were almost linearly related in all process conditions applied except in the case of hydrolysate addition. Optimum conditions for hydrolysis and solubilization were obtained as 10 g L−1 protein concentration, 4 mL L−1 enzyme concentration, 45 °C and pH 6.5. The mechanism of the kinetics was explained by taking into consideration association binding between the enzyme and substrate. The kinetics of hydrolysis and solubilization for all experiments performed were represented by exponential association equations that have not been used in the literature before. Also, to illustrate the effect of process variables on hydrolysis and solubilization, some modelling studies were performed. Copyright © 2007 Society of Chemical Industry
Quorum sensing detected by atomic force microscopy imaging of corrals surrounding multicellular arrangement of bacteria
Authors: Teschke Omar , De Souza Elizabeth Fátima , Silva‐Stenico Maria Estela , Fiore Marli De Fátima , Etchegaray Augusto 
Published: October 2007

AbstractConnectivity of the glycocalyx covering of small communities of Acidithiobacillus ferrooxidans bacteria deposited on hydrophilic mica plates was imaged by atomic force microscopy. When part of the coverage was removed by water rinsing, an insoluble structure formed by corrals surrounding each individual bacterium was observed. A collective ring structure with clustered bacteria (≥3) was observed, which indicates that the bacteria perceived the neighborhood in order to grow a protective structure that results in smaller production of exopolysaccharides material. The most surprising aspect of these collective corral structures was that they occur at a low bacterial cell density. The deposited layers were also analyzed by confocal Raman microscopy and shown to contain polysaccharides, protein, and glucoronic acid. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Histological evaluation on bone regeneration of dental implant placement sites grafted with a self‐setting α‐tricalcium phosphate cement
Authors: Nakadate Masayoshi , Amizuka Norio , Li Minqi , Freitas Paulo H.L. , Oda Kimimitsu , Nomura Shuichi , Uoshima Katsumi , Maeda Takeyasu 
Published: October 2007

AbstractThis study aimed to evaluate the histological characteristics of the new bone formed at dental implant placement sites concomitantly grafted with a self‐setting tricalcium phosphate cement (BIOPEX‐R®). Standardized defects were created adjacent to the implants in maxillae of 4‐week‐old male Wistar rats, and were concomitantly filled with BIOPEX‐R®. Osteogenesis was examined in two sites of extreme clinical relevance: (1) the BIOPEX‐R®‐grafted surface corresponding to the previous alveolar ridge (alveolar ridge area), and (2) the interface between the grafting material and implants (interface area). At the alveolar ridge area, many tartrate‐resistant acid phosphatase (TRAPase)‐reactive osteoclasts had accumulated on the BIOPEX‐R® surface and were shown to migrate toward the implant. After that, alkaline phosphatase (ALPase)‐positive osteoblasts deposited new bone matrix, demonstrating their coupling with osteoclasts. On the other hand, the interface area showed several osteoclasts initially invading the narrow gap between the implant and graft material. Again, ALPase‐positive osteoblasts were shown to couple with osteoclasts, having deposited new bone matrix after bone resorption. Transmission electron microscopic observations revealed direct contact between the implant and the new bone at the interface area, although few thin cells could still be identified. At both the alveolar ridge and the interface areas, newly formed bone resembled compact bone histologically. Also, concentrations of Ca, P, and Mg were much alike with those of the preexistent cortical bone. In summary, when dental implant placement and grafting with BIOPEX‐R® are done concomitantly, the result is a new bone that resembles compact bone, an ideal achievement in reconstructive procedures for dental implantology. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Simultaneous determination of gemcitabine and its main metabolite, dFdU, in plasma of patients with advanced non‐small‐cell lung cancer by high‐performance liquid chromatography‐tandem mass spectrometry
Authors: Marangon Elena , Sala Federica , Caffo Orazio , Galligioni Enzo , D'Incalci Maurizio , Zucchetti Massimo 
Published: October 2007

AbstractGemcitabine, 2′,2′‐difluoro‐2′‐deoxycytidine (dFdC) is a pyrimidine antimetabolite employed against several human malignancies. It undergoes intracellular activation to the pharmacologically active triphosphate form (dFdCTP) and metabolic inactivation to the metabolite 2′,2′‐difluorodeoxyuridine (dFdU). In order to investigate the human plasma pharmacokinetics of dFdC and dFdU, we developed and validated an HPLC‐MS/MS method, adding 2′‐deoxycytidine as internal standard and simply precipitating the protein with acetonitrile. The method requires a small sample (125 µl), and it is rapid and selective, allowing good resolution of peaks from the plasma matrix in only 7 min. It is sensitive, precise and accurate, with overall precision, expressed as CV%, always less than 10.0% for both analytes and high recovery: ≥ 80%. The limits of detection for dFdC and dFdU were 0.1 and 1.1 ng/ml, but considering the high concentrations in the plasma of patients investigated, we set the limit of quantitation at 20 ng/ml (0.08 µM) for dFdC and 250 ng/ml for dFdU, and validated the assay up to the dFdC concentration of 6.0 µg/ml (22.8 µM). The method was successfully used to study the drug pharmacokinetics in patients with advanced non‐small‐cell lung cancer in a phase II trial with gemcitabine administered as a fixed dose‐rate infusion. Copyright © 2007 John Wiley & Sons, Ltd.
Mass spectrometric study of the ionized C60: (γ‐Cyclodextrin)2 inclusion complex by collision induced dissociation
Authors: Greisch Jean‐François , Kyritsoglou Sam , Leyh Bernard , De Pauw Edwin 
Published: October 2007

AbstractThe water soluble inclusion complex [C60:(γ‐cyclodextrin)2] has been characterized using electrospray tandem mass spectrometry and collision induced dissociation. [C60:(γ‐cyclodextrin)2] ions were detected in the gas phase as doubly deprotonated, doubly protonated and doubly sodiated ions. The absence of monocharged complex ions following electronebulization is a likely consequence of the dimeric nature and structural symmetry of the inclusion complex. The collision induced dissociation of positive ions led exclusively to the observation of the protonated and sodiated cyclodextrin ions as well as their fragments. In negative ion mode the closed shell anion C60H− was the dominant fragment detected at low collision energies whereas at higher collision energies the signal corresponding to deprotonated cyclodextrin units becomes significant. Since C602− has been reported to have a nonnegligible basicity compared to C60 and C60−, it is likely that the proton transfer involved in the formation of the C60H− anion occurs following transfer of the two electrons from the deprotonated γ‐cyclodextrins to the fullerene. Finally, the charge state of the inclusion complex ions is also shown to affect the interaction strengths between its subunits. The relative stabilities of the three ionic species studied in gas phase following electronebulization are as follows: [C60:(γ‐cyclodextrin)2 + 2H]2+ < [C60:(γ‐cyclodextrin)2− 2H]2− < [C60:(γ‐cyclodextrin)2 + 2Na]2+. Copyright © 2007 John Wiley & Sons, Ltd.
Modified Z‐transform‐based FDTD algorithm for the anisotropic perfectly matched layer
Authors: Li Jianxiong , Dai Jufeng 
Published: October 2007

AbstractA modified Z‐transform‐based algorithm for implementing the D‐H anisotropic perfectly matched layer (APML) is presented for truncating the finite‐difference time‐domain (FDTD) lattices. The main advantage is that, as compared with the previous Z‐transform‐based implementation for the D‐H APML, the proposed algorithm requires less auxiliary variables in the PML regions, and thus the memory requirement and the computational time are saved. These formulations are simple and independent of the material properties of the FDTD computational domain. Two numerical tests have been carried out to validate these formulations. Copyright © 2007 John Wiley & Sons, Ltd.
SPICE‐compatible stamps for semi‐discrete approximations of Maxwell's equations
Authors: Ramachandran Aravind , Ramachandran Anand , Cangellaris Andreas C. 
Published: October 2007

AbstractThis article presents the formulation of equivalent circuit stamps derived from the semi‐discrete form of Maxwell's equations. In particular, when a rectangular Yee's lattice is used for the spatial discretization of Faraday's and Ampere's laws, the stamps assume simple forms in terms of lumped circuit elements and dependent sources. It is shown that there is a very close relationship between the semi‐discrete Maxwell's system and the mesh analysis formalism of Kirchhoff's voltage and current laws. Boundary conditions, including a first‐order absorbing boundary condition, are extended to equivalent circuit descriptions. The utilization of the SPICE‐compatible equivalent circuit stamp formalism for the numerical solution of Maxwell's equations using SPICE is illustrated for the case of the calculation of the resonant frequencies of a perfectly conducting, rectangular cavity resonator. Copyright © 2007 John Wiley & Sons, Ltd.
Insulin‐like growth factors, angiopoietin‐2, and pigment epithelium–derived growth factor in the hypoxic retina
Authors: Sivakumar V. , Zhang Y. , Ling E. A. , Foulds W. S. , Kaur C. 
Published: October 2007

AbstractAs the response of the adult retina to hypoxia is likely to differ from that already established in the neonatal animal, this study was undertaken to examine the expression patterns of insulin‐like growth factor‐I (IGF‐I) and ‐II (IGF‐II), angiopoietin‐2 (Ang‐2), and pigment epithelium–derived growth factor (PEDF) in normal and hypoxic retinas of adult rats. In the latter, the retinas were examined from 3 hr to 14 days after hypoxic exposure. The mRNA and protein expression of IGF‐I, IGF‐II, Ang‐2, and PEDF in the retina was determined by real‐time RT‐PCR, Western blotting, and immunohistochemistry. The results showed up‐regulated expression of IGF‐I, IGF‐II, and Ang‐2 mRNA and protein in response to hypoxia, whereas PEDF expression was drastically reduced, suggesting that increased expression of IGF‐I and IGF‐II may be involved not only in neovascularization but also in neuroprotection in hypoxic conditions. The up‐regulation of Ang‐2, a proangiogenic factor, and the down‐regulation of PEDF, an antiangiogenic factor, is indicative of an imbalance between pro‐ and antiangiogenic factors in the hypoxic retina that may favor neovascularization. This was supported by the increased density of rat endothelial cell antigen–1 (RECA‐1) protein quantification and RECA‐1‐stained blood vessels in the inner retina. © 2007 Wiley‐Liss, Inc.
Inhibition of N‐cadherin and β‐catenin function reduces axon‐induced Schwann cell proliferation
Authors: Gess Burkhard , Halfter Hartmut , Kleffner Ilka , Monje Paula , Athauda Gagani , Wood Patrick M. , Young Peter , Wanner Ina B. 
Published: October 2007

AbstractN‐cadherin and β‐catenin are involved in cell adhesion and cell cycle in tumor cells and neural crest. Both are expressed at key stages of Schwann cell (SC) development, but little is known about their function in the SC lineage. We studied the role of these molecules in adult rat derived SC‐embryonic dorsal root ganglion cocultures by using low‐Ca2+ conditions and specific blocking antibodies to interfere with N‐cadherin function and by using small interfering RNA (siRNA) to decrease β‐catenin expression in both SC‐neuron cocultures and adult rat‐derived SC monocultures. N‐cadherin blocking conditions decreased SC‐axon association and reduced axon‐induced SC proliferation. In SC monocultures, β‐catenin reduction diminished the proliferative response of SCs to the mitogen β1‐heregulin, and, in SC‐DRG cocultures, β‐catenin reduction inhibited axon‐contact‐dependent SC proliferation. Stimulation of SC cultures with β1‐heregulin increased total β‐catenin protein amount, phosphorylation of GSK‐3β and β‐catenin presence in nuclear extracts. In conclusion, our findings suggest a previously unrecognized contribution of β‐catenin and N‐cadherin to axon‐induced SC proliferation. © 2007 Wiley‐Liss, Inc.
F3/contactin‐related proteins in Helix pomatia nervous tissue (HCRPs): Distribution and function in neurite growth and neurotransmitter release
Authors: Milanese Chiara , Fiumara Ferdinando , Bizzoca Antonella , Giachello Carlo , Leitinger Gerd , Gennarini Gianfranco , Montarolo Pier Giorgio , Ghirardi Mirella 
Published: October 2007

AbstractBy using antibodies against mouse F3/contactin, we found immunologically related glycoproteins expressed in the nervous tissue of the snail Helix pomatia. Helix contactin‐related proteins (HCRPs) include different molecules ranging in size from 90 to 240 kD. Clones isolated from a cDNA expression library allowed us to demonstrate that these proteins are translated from a unique 6.3‐kb mRNA, suggesting that their heterogeneity depends on posttranslational processing. This is supported by the results of endoglycosidase F treatment, which indicate that the high‐molecular‐weight components are glycosylation variants of the 90‐kD chain. In vivo and in cultures, HCRPs antibodies label neuronal soma and neurite extensions, giving the appearance of both cytoplasmic and cell surface immunostaining. On the other hand, no expression is found on nonneural tissues. Functionally, HCRPs are involved in neurite growth control and appear to modulate neurotransmitter release, as indicated by the inhibiting effects of specific antibodies on both functions. These data allow the definition of HCRPs glycoproteins as growth‐promoting molecules, suggesting that they play a role in neurite development and presynaptic terminal maturation in the invertebrate nervous system. © 2007 Wiley‐Liss, Inc.