bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pigment epithelium‐derived factor acts as an opponent of growth‐stimulatory factors in retinal glial–endothelial cell interactions
Authors: Yafai Yousef , Lange Johannes , Wiedemann Peter , Reichenbach Andreas , Eichler Wolfram 
Published: February 2007

AbstractPigment epithelium‐derived factor (PEDF), a glycoprotein with pleiotropic functions, is naturally occuring in the eye and considered as crucial to prevent pathological angiogenesis. Since retinal glial (Müller) cells produce PEDF, the authors have studied its impact on glial–endothelial cellular interactions. Bovine retinal endothelial cells were cultured in the presence of culture media originating from primary Müller cells, and endothelial proliferation as well as phosphorylation of the mitogen‐activated protein kinases extracellular signal‐regulated kinases (ERK)‐1/‐2 were investigated. The concerted activity of Müller‐cell derived soluble mediators attenuated endothelial proliferation and ERK‐1/‐2 activation, regardless of whether the Müller cells were preincubated under normoxia or hypoxia, and even though the endothelial cells were stimulated by vascular endothelial growth factor‐A (VEGF). This inhibitory activity was no longer demonstrable if high levels of basic fibroblast growth factor or VEGF were supplied, suggesting that in cases of pathological neovascularization, overproduction of proangiogenic mediators overrides the “antiangiogenic background” provided by Müller cells. However, neutralizing the activity of PEDF partially restored endothelial cell proliferation and resulted in increased ERK‐1/‐2 activation, which is in concordance with findings demonstrating that exogenously applied PEDF is able to suppress VEGF‐induced ERK‐1/‐2 phosphorylation. PEDF production by Müller cells is not only regulated by retinal oxygen but also by the activity of soluble factors released from retinal endothelial cells. For instance, PEDF levels were significantly elevated in glial (Müller)–endothelial cell cocultures as compared with bovine retinal endothelial cell‐free Müller cell cultures. These results have implications for the pathogenesis of retinal neovascularization since the Müller cell may be regarded as a central control element which modulates retinal PEDF levels and, thus, is of critical importance for adjusting the balance between proangiogenic and antiangiogenic mediators. © 2007 Wiley‐Liss, Inc.
Effects of low‐level arsenic exposure on the developmental toxicity of anilofos in rats
Authors: Aggarwal Manoj , Wangikar P. B. , Sarkar S. N. , Rao G. S. , Kumar Dinesh , Dwivedi P. , Malik J. K. 
Published: February 2007

AbstractIn view of the increased use of anilofos for crop protection and ever increasing arsenic levels in drinking water in many countries, the coexistence of arsenic and anilofos in the environment is a reality and simultaneous exposure of humans and animals to these contaminants could be potentially hazardous. The aim of the present study was to examine whether coexposure to arsenic at the groundwater contamination level could alter the embryofetal toxicity of anilofos in rat model. Anilofos (100 mg kg−1 day−1) and sodium arsenite (1 mg arsenic kg−1 day−1) were administered by gavage either individually or in combination to the pregnant rats from day 6 to day 15 of gestation. Arsenic did not produce any significant effects either on maternal or fetal parameters at the given dose. Anilofos alone significantly decreased maternal weight gain, feed and water intakes, gravid uterine weights, number of live fetuses and fetal body weights and increased resorptions. There were increased incidences of gross, skeletal and visceral anomalies in the fetuses of anilofos‐treated group. The main skeletal abnormality was increased intercostal space, while the visceral anomaly was an interventricular septal defect. Treatment with the combination of arsenic and anilofos significantly enhanced the fetal changes with much greater magnitude compared with the effects produced by anilofos alone. Anomalies such as midfacial cleft, exencephaly and anophthalmia were seen only in the fetuses of the combination group. The results show that anilofos interferes with embryofetal development and coexposure with arsenic at environmentally realistic concentrations produces additive or synergistic effects on the developmental toxicity of anilofos in rats. Copyright © 2007 John Wiley & Sons, Ltd.
Deltamethrin induces mitochondrial membrane permeability and altered expression of cytochrome C in rat brain
Authors: Chen Dan , Huang Xiaowei , Liu Linlin , Shi Nian 
Published: February 2007

AbstractDeltamethrin is a type II synthetic pyrethroid insecticide and is used extensively. Numerous studies have demonstrated that deltamethrin can cause severe central nervous system symptoms. The mechanism of neuro‐toxicity caused by deltamethrin is still poorly understood. This study investigated the effect of deltamethrin on the mitochondria‐mediated apoptosis pathway in rat brain. The cortex and hippocampus mitochondrial membrane potential, permeability transition, expression of cytochrome c and activity of cytochrome c oxidase was assayed at 5, 24, 48 and 72 h following deltamethrin treatment. The study observed that the membrane potential, change of absorbance at 540 nm (A540), intensities of cytochrome c in mitochondria and activity of cytochrome c oxidase in the cortex and hippocampus of treated groups were significantly lower than those of the control group. The results of the study demonstrated that deltamethrin induced a decreased mitochondrial membrane potential and increased permeability, and reduced the expression of cytochrome c, thus depressing the activity of cytochrome c oxidase significantly. It indicates that deltamethrin may have an effect on mitochondria‐mediated apoptosis of nerve cells in the rat brain. Copyright © 2007 John Wiley & Sons, Ltd.
Histological evaluation of an impacted bone graft substitute composed of a combination of mineralized and demineralized allograft in a sheep vertebral bone defect
Authors: Fujishiro Takaaki , Bauer Thomas W. , Kobayashi Naomi , Kobayashi Hideo , Sunwoo Moon Hae , Seim Howard B. , Turner A. Simon 
Published: February 2007

AbstractDemineralized bone matrix (DBMs) preparations are a potential alternative or supplement to autogenous bone graft, but many DBMs have not been adequately tested in clinically relevant animal models. The aim of current study was to compare the efficacy of a new bone graft substitute composed of a combination of mineralized and demineralized allograft, along with hyaluronic acid (AFT Bone Void Filler™) with several other bone graft materials in a sheep vertebral bone void model. A drilled defect in the sheep vertebral body was filled with either the new DBM preparation, calcium sulfate (OsteoSet™), autologous bone graft, or left empty. The sheep were euthanized after 6 or 12 weeks, and the defects were examined by histology and quantitative histomorphometry. The morphometry data were analyzed by one‐way analysis of variance with the post hoc Tukey‐Kramer test or the Student's t‐test. All of the bone defects in the AFT DBM preparation group showed good new bone formation with variable amounts of residual DBM and mineralized bone graft. The DBM preparation group at 12 weeks contained significantly more new bone than the defects treated with calcium sulfate or left empty (respectively, p < 0.05, p < 0.01). There was no significant difference between the DBM and autograft groups. No adverse inflammatory reactions were associated with any of the three graft materials. The AFT preparation of a mixture of mineralized and demineralized allograft appears to be an effective autograft substitute as tested in this sheep vertebral bone void model. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Effects of Cymbopogon citratus L. essential oil on the growth, morphogenesis and aflatoxin production of Aspergillus flavus ML2‐strain
Authors: Helal G. A. , Sarhan M. M. , Abu Shahla A. N. K. , Abou El‐Khair E. K. 
Published: February 2007

AbstractThe mycelial growth of Aspergillus flavus Link was completely inhibited using 1.5 (µl/ml or 2.0 (µl/ml of Cymbopogon citratus essential oil applied by fumigation or contact method in Czapek's liquid medium, respectively. This oil was found also to be fungicidal at the same concentrations. The sublethal doses 1.0 and 1.5 (µl/ml inhibited about 65% of fungal growth after five days of incubation and delayed conidiation as compared with the control. Microscopic observations using Light Microscope (LM), Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM) were carried out to determine the ultra structural modifications of A. flavus hyphae after treatment with C. citratus essential oil. The hyphal diameter decreased and hyphal wall appeared as precipitates and disappeared in some regions. This oil also caused plasma membrane disruption and mitochondrial structure disorganization. Moreover, Ca+2, K+ and Mg+2 leakages increased from the fumigated mycelium and its total lipid content decreased, while the saturated and unsaturated fatty acids increased. One of the most important results obtained during this study was the ability of C. citratus essential oil at its sublethal dose to completely inhibit aflatoxin B1 production from A. flavus. These findings increase the possibility of exploiting C. citratus essential oil as an effective inhibitor of biodegradation and storage contaminating fungi and also in fruit juice preservation. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation and characterization of pathogenic Vibrio parahaemolyticus from diseased post‐larvae of abalone Haliotis diversicolor supertexta
Authors: Cai Junpeng , Li Juan , Thompson Kim D. , Li Chuanxia , Han Hongcao 
Published: February 2007

AbstractMass mortality among the post‐larvae of cultured abalone Haliotis diversicolor supertexta has occurred on the south coast of China since 2002. The diseased abalone are generally 10 to 30 days old, and typical signs of the disease include them turning white in colour and falling off the diatom films on which they were cultured. Among sixteen different motile bacteria isolated from the diseased post‐larvae, four were identified as Vibrio parahaemolyticus on the basis of biochemical characteristics when compared with those of a V. parahaemolyticus type strain ATCC 17802T. Isolate 25, a representative isolate of V. parahaemolyticus recovered from diseased abalone, was virulent for the post‐larvae with an LD50 value of 3.5 × 105 CFU (colony forming units)/ml. All moribund post‐larvae artificially infected with the bacterium turned white and fell off the diatom films on which they were cultured as seen to occur during natural outbreaks of the disease, and it was possible to recover the bacterium from artificially infected post‐larvae. The results of the study indicate that V. parahaemolyticus is a pathogenic bacterium to abalone post‐larvae. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cloning and characterization of Fpmtr1, an amino acid transporter gene of Fusarium proliferatum (Gibberella intermedia)
Authors: Jeney Apor , Béki Emese , Keszthelyi Anita , Leslie John F. , Hornok László 
Published: February 2007

AbstractFpmtr1, an amino acid transporter gene from Fusarium proliferatum was strongly expressed during conidial germination and repressed in late stationary phase. To identify the specific function of this gene, ΔFpmtr1 knock‐out mutants were generated by gene replacement. Vegetative growth of the ΔFpmtr1 mutants was normal both in liquid and on solid media, but conidial germination was delayed. The ΔFpmtr1 mutants and the wild type were equally fertile when used as males in sexual crosses, however if the mutants were used as the female parent then the fertility of the cross decreased dramatically. Inactivation of Fpmtr1 abolished vegetative self‐incompatibility in strain ITEM 2287 of F. proliferatum, but the ΔFpmtr1 mutants were still vegetatively incompatible with the other strains of the fungus. Endophytic colonization capability of the mutants, assessed on maize seedlings also was adversely affected. These data suggest that Fpmtr1 is involved in multiple developmental processes related to both sexual and parasexual events in F. proliferatum. Furthermore, the fungus might have problems in adapting to a less than optimal environment if this otherwise dispensable transporter has been inactivated. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Isolation and characterisation of Ralstonia solanacearum strains from Solanaceae crops in Ethiopia
Authors: Lemessa Fikre , Zeller Wolfgang 
Published: February 2007

AbstractEighty one isolates of Ralstonia solanacearum ‐like bacteria on triphenyl tetrazolium chloride (TTC) medium were collected from different Solanaceae crops (i.e. potato, tomato and pepper plants and potato tubers) at various sites in Ethiopia. Of these, 62 strains were identified as R. solanacearum based on their cultural characteristics on TTC medium, tomato pathogenicity bioassay, carbon source utilisation patterns and a specific PCR‐based assay. By Hayward's classification method, based on carbon source utilisation, 19 of the 62 R. solanacearum strains were identified as biovar I and 43 strains were identified as biovar II. The biovar I strains exhibited a high growth rate at high temperatures (37 °C). Whereas the growth rate of biovar II strains was greatest at lower temperatures (22 °C). Biovar I strains had broader host range than biovar II strains, which were limited to potato, tomato, and eggplant. To our knowledge, this is the first report of R. solanacearum biovar I in Ethiopia. The existence of biovar I strains in Ethiopia raises concerns because they have a broader host range than biovar II strains. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Superoxide dismutases of heavy metal resistant streptomycetes
Authors: Schmidt Astrid , Schmidt André , Haferburg Götz , Kothe Erika 
Published: February 2007

AbstractHeavy metal tolerant and resistant strains of streptomycetes isolated from a former uranium mining site were screened for their superoxide dismutase expression. From the strains tolerating high concentrations of different heavy metals, one was selected for its tolerance of concentrations of heavy metals (Ni, Cu, Cd, Cr, Mn, Zn, Fe). This strain, Streptomyces acidiscabies E13, was chosen for the purpose of superoxide dismutase analysis. Gel electrophoresis and activity staining revealed only one each of a nickel (NiSOD) and an iron (FeZnSOD) containing superoxide dismutase as shown by differential enzymatic repression studies. The gene for nickel containing superoxide dismutase, sodN, was cloned and sequenced from this strain. The genomic sequence shows 92.7% nucleotide identity and 96.1% amino acid identity to sodN of S. coelicolor. Expression can be activated by nickel as well as other heavy metals and active enzyme is produced in media lacking nickel but containing copper, iron or zinc. Thus, the selected strain is well suited for further characterization of the enzyme encoded by sodN. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Gene expressions and enzyme analyses in theSchizosaccharomyces pombe Δpap1transcription factor mutant exposed to Cd2+
Authors: Takács Krisztina , Gazdag Zoltán , Raspor Peter , Pesti Miklós 
Published: February 2007

AbstractThe objective of this study was to investigate the role of the Pap1 transcription factor in response to long‐term Cd2+stress. TheSchizosaccharomyces pombewild‐type strain and theΔpap1mutant, treated with 0.5 mM CdSO4, were used in antioxidant enzyme and gene expression experiments. TheΔpap1mutant proved to be sensitive to Cd2+in the spot test assay, suggesting that the Pap1 transcription factor plays an important role in the response to Cd2+stress. The Cd2+uptake was the same in both strains. Determination of the superoxide level in the wild‐type strain proved that superoxide was generated, suggesting that long‐term Cd2+treatment could trigger oxidative stress. Furthermore, theΔpap1mutant displayed higher amounts of superoxide. These results were supported by the significantly lower amount of peroxide generated in the reaction catalyzed by superoxide dismutase (SOD). TheΔpap1mutant had a significantly lower glutathione S‐transferase specific activity than that of the wild‐type strain during long‐term Cd2+stress, caused by the lower GSH and sulfide assimilation. We have demonstrated that GST III activity was not induced by Cd2+stress in theΔpap1mutant. The overall low GST activity was not sufficient for the cell to eliminate Cd2+caused damage and could result in a Cd2+‐sensitive phenotype of theΔpap1mutant. The RT‐PCR and Northern blot experiments proved thatgst2was not induced either by short‐term or by long‐term Cd2+treatment. TheSPCC965.06(a putative K+ion channel subunit) gene expression increased, while thehmt1(an ABC‐type vacuolar transporter protein) expression decreased in both strains. No detectable alteration in the mRNA levels of,gpx1,hmt2,sod1,sod, andtrx1was observed. SOD enzyme analyses revealed that the absence of Pap1 protein could result in a lower SODs activity and affect the sulfate assimilation. This is the first report on the fact that the Pap1 transcription factor could play an important role in the cellular post‐transcriptional/post‐translational enzyme activity induction processes of SODs that occur in response to Cd2+. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Structure and properties of rubber blends with ferromagnetic fillers
Authors: Ürögiová E. , Hudec I. , Bellušová D. , Šuri P. 
Published: February 2007

AbstractThe influence of hard magnetic strontium ferrite filler content on the structure, vulcanization characteristics, magnetic and mechanical properties of rubber blends was studied. The variations of rubber–ferrite composites properties were evaluated as a function of ferrite and carbon black loading by application of the design of the experimental method. Obtained results revealed that the cure time is not influenced by ferrite and carbon black content in rubber blends. The remanent magnetization and tensile strength of filled rubber blends are linearly dependent on the mass fraction of the magnetic filler in rubber blends, while the elongation at break and modules are influenced by the weight content of ferrite particles and carbon black in rubber blends. Copyright © 2007 John Wiley & Sons, Ltd.
Poly(propylene) with micro‐fillers—the way of enhancement of toughness
Authors: Kucera J. , Nezbedova E. 
Published: February 2007

AbstractCommercially available poly(propylene)(PP)(MOSTEN, MFR = 4 g/10 min) supplied by a Czech company Chemopetrol Litvínov and precipitated calcium carbonate (CaCO3) was used for this study. The CaCO3 particles were coated with surface agent improving their dispersion.The effect of the PP structure, the volume content and surface coating of particles on the decisive mechanical properties (dynamic modulus of elasticity and dynamic fracture toughness) was evaluated by means of dynamic mechanical thermal analysis (DMTA) and instrumented Charpy tester. The dispersion of the filler particles was qualitatively estimated by scanning electron microscopy (SEM). The change of solid phase PP ratio was evaluated utilizing differential scanning calorimetry (DSC) and nuclear magnetic resonance (pulsed 1H‐NMR).The composites in the study demonstrated the enhanced toughness with respect to the native PP. The correlation between the structure and fracture parameters was confirmed. Copyright © 2007 John Wiley & Sons, Ltd.
Perfluorocarbons: Life sciences and biomedical uses Dedicated to the memory of Professor Guy Ourisson, a true RENAISSANCE man.
Authors: Krafft Marie Pierre , Riess Jean G. 
Published: February 2007

AbstractPerfluorocarbons are primarily characterized by outstanding chemical and biological inertness, and intense hydrophobic and lipophobic effects. The latter effects provide a powerful noncovalent, labile binding interaction that can promote selective self‐ assembly. Perfluoro compounds do not mimic nature, yet they can offer abiotic building blocks for the de novo design of functional biopolymers and alternative solutions to physiologically vital issues. They offer new tags useful for molecular recognition, selective sorting, and templated binding (e.g., selective peptide and nucleic acid pairing). They also stabilize membranes and provide micro‐ and nanocompartmented fluorous environments. Perfluorocarbons provide inert, apolar carrier fluids for lab‐on‐a‐chip experiments and assays using microfluidic technologies. Low water solubility, combined with high vapor pressure, allows stabilization of injectable microbubbles that serve as contrast agents for diagnostic ultrasound imaging. High gas solubilities are the basis for an abiotic means for intravascular oxygen delivery. Other biomedical applications of fluorocarbons include lung surfactant replacement and ophthalmologic aids. Diverse colloids with fluorocarbon phases and/or shells are being investigated for molecular imaging using ultrasound or magnetic resonance, and for targeted drug delivery. Highly fluorinated polymers provide a range of inert materials (e.g., fluorosilicons, expanded polytetrafluoroethylene) for contact lenses, reconstructive surgery (e.g., vascular grafts), and other devices. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1185–1198, 2007.
Isolation and characterization of a novel simazine‐degrading β‐proteobacterium and detection of genes encoding s‐triazine‐degrading enzymes
Authors: Iwasaki Akio , Takagi Kazuhiro , Yoshioka Yuichi , Fujii Kunihiko , Kojima Yuki , Harada Naoki 
Published: February 2007

AbstractA moderately persistent herbicide, simazine, has been used globally and detected as a contaminant in soil and water. The authors have isolated a simazine‐degrading bacterium from a simazine‐degrading bacterial consortium that was enriched using charcoal as a microhabitat. The isolate, strain CDB21, was gram‐negative, rod‐shaped (0.5–0.6 µm × 1.0–1.2 µm) and motile by means of a single polar flagellum. Based on 16S rRNA sequence analysis, strain CDB21 was identified as a novel β‐proteobacterium exhibiting 100% sequence identity with the uncultured bacterium HOClCi25 (GenBank accession number AY328574). PCR using primers that were specific for the genes of the atrazine‐degrading enzymes (atzABCDEF) of Pseudomonas sp. strain ADP showed that strain CDB21 also possessed the entire set of genes of these enzymes. Nucleotide sequences of the atzCDEF genes of strain CDB21 were 100% identical to those of Pseudomonas sp. strain ADP. Sequence identity of the atzA genes between these bacteria was 99.7%. The 398‐nucleotide upstream fragment of the atzB gene of strain CDB21 was 100% identical to ORF30 of Pseudomonas sp. strain ADP, and the 1526‐nucleotide downstream fragment showed 99.8% sequence similarity to the atzB gene of the pseudomonad. Copyright © 2007 Society of Chemical Industry
Temporal synergism by microencapsulation of piperonyl butoxide and α‐cypermethrin overcomes insecticide resistance in crop pests
Authors: Bingham Georgina , Gunning Robin V , Gorman Kevin , Field Linda M , Moores Graham D 
Published: February 2007

AbstractA microencapsulated formulation that gives a burst release of piperonyl butoxide (PBO) several hours before a burst release of a conventional pyrethroid can effectively overcome metabolic resistance in Bemisia tabaci Gennadius, Helicoverpa armigera (Hübner), Aphis gossypii Glover and Myzus persicae Sulzer. This increase in efficacy against resistant pests was reflected in a field trial against B. tabaci on cotton, eliminating the need for two treatments. The ratio between the active insecticide and the synergist was found to be crucial in reducing resistance factors. Copyright © 2007 Society of Chemical Industry