bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agonistic behavior and electrical stimulation of the antennae induces Fos‐like protein expression in the male cricket brain
Authors: Ghosal Kaushik , Naples Scott P. , Rabe Alexander R. , Killian Kathleen A. 
Published: April 2010

AbstractImmediate early genes (IEG) such as c‐Fos and Fos‐related antigens (FRA) have been used as markers of neuronal activation. In this study, we determined whether the expression of c‐Fos/FRAs is increased in the brains of adult male Acheta domesticus crickets following agonistic interactions. We looked for c‐Fos/FRA proteins in the brain of un‐fought, control male crickets and of dominant and subordinate male crickets sacrificed at different time periods following an agonistic interaction. Using immunoblot analysis, we found four different c‐Fos/FRA‐like proteins in the adult cricket brain. Continuous agonistic interaction increased c‐Fos/FRA protein expression in the brains of subordinate males compared to control and dominant males. In addition, direct electrical stimulation of the male cricket antennae increased c‐Fos/FRA‐like protein in the brain. We identified the specific brain regions that exhibit c‐Fos/FRA‐like immunoreactivity in crickets. We detected c‐Fos/FRA‐like cellular immunoreactivity in different functional regions of the adult brain including the pars intercerebralis, protocerebrum, deutocerebrum, and the cortex of the mushroom bodies. © 2010 Wiley Periodicals, Inc.
Synthesis and Structure‐Activity Relationship Studies of Pyrazole‐based Heterocycles as Antitumor Agents
Authors: Farag Ahmad M. , Mayhoub Abdelrahman S. , Eldebss Taha M. A. , Amr Abdel‐Galil E. , Ali Korany A. K. , Abdel‐Hafez Naglaa A. , Abdulla Mohamed M. 
Published: April 2010

AbstractSeveral 4‐cyano‐1,5‐diphenylpyrazoles attached to different heterocyclic ring systems at position 3 were synthesized starting from ethyl 4‐cyano‐1,5‐diphenyl‐1H‐pyrazole‐3‐carboxylate 1. The newly synthesized compounds were tested in vivo for their anti‐estrogenic effects and evaluated in vitro for their cytotoxic properties against estrogen‐dependent tumors. 3‐(5‐Mercapto‐1,3,4‐oxadiazole‐2‐yl)‐1,5‐diphenyl‐1H‐pyrazole‐4‐carbonitrile 13 revealed the highest cytotoxic activity with a GI50 value equal to 40 nM against the IGROVI ovarian tumor cell line. It also showed an anti‐estrogen activity 1.6 more effective than the reference drug, in addition to a high tolerable dose. 3‐(5‐(Methylthio)‐4‐phenyl‐4H‐1,2,4‐triazol‐3‐yl)‐1,5‐diphenyl‐1H‐pyrazole‐4‐carbonitrile 7 was found to have the highest anti‐estrogenic activity, while 1,5‐diphenyl‐3‐[5‐(phenylamino)‐1,3,4‐thiadiazol‐2‐yl]‐1H‐pyrazole‐4‐carbonitrile 11 showed the lowest activity. The oral LD50 values revealed that most of the tested compounds are relatively nontoxic.
Behaviors, adverse events, and dispositions: An empirical study of online discretion and information control
Authors: Cheshire Coye , Antin Judd , Churchill Elizabeth 
Published: April 2010

AbstractIn this article, the authors develop hypotheses about three key correlates of attitudes about discretionary online behaviors and control over one's own online information: frequency of engaging in risky online behaviors, experience of an online adverse event, and the disposition to be more or less trusting and cautious of others. Through an analysis of survey results, they find that online adverse events do not necessarily relate to greater overall Web discretion, but they do significantly associate with users' perceptions of Web information control. However, the frequencies with which individuals engage in risky online activities and behaviors significantly associate with both online discretion and information control. In addition, general dispositions to trust and be cautious are strongly related to prudent Internet behavior and attitudes about managing personal online information. The results of this study have clear consequences for our understanding of behaviors and attitudes that might lead to greater online social intelligence, or the ability to make prudent decisions in the presence of Internet uncertainties and risks. Implications for theory and practice are discussed.
The relation between Eigenfactor, audience factor, and influence weight
Authors: Waltman Ludo , van Eck Nees Jan 
Published: April 2010

AbstractWe present a theoretical and empirical analysis of a number of bibliometric indicators of journal performance. We focus on three indicators in particular: the Eigenfactor indicator, the audience factor, and the influence weight indicator. Our main finding is that the last two indicators can be regarded as a kind of special case of the first indicator. We also find that the three indicators can be nicely characterized in terms of two properties. We refer to these properties as the property of insensitivity to field differences and the property of insensitivity to insignificant journals. The empirical results that we present illustrate our theoretical findings. We also show empirically that the differences between various indicators of journal performance are quite substantial.
The Origin of the Halogen Effect on the Phthalocyanine Green Pigments
Authors: Lee Sang Uck , Kim Jong Chan , Mizuseki Hiroshi , Kawazoe Yoshiyuki 
Published: April 2010

AbstractThe structure and the electronic and optical properties of halogenated copper‐phthalocyanine (nα,mβ(Hal)‐CuPc) molecules are investigated, according to the variation in the substituted halogen‐atom species (Hal=Cl or Br) at the α and β positions of isoindole ring with different numbers (n and m=0, 4, 8, or 16). Our results show that the halogen effect mainly results from a structural deformation rather than caused by electronic effects. A nonplanar deformation of the phthalocyanine chromophore of the nα,mβ(Hal)‐CuPc molecule causes a significant change only in the HOMO and HOMO‐1 levels, rather than in the LUMO levels, which leads to the appearance of a green color arising from the large red‐shifts of the Soret and Q bands. The present result may serve as an important reference point for designing novel halogen‐free green pigments, in accordance with the environmental regulations for the restriction of hazardous substances (RoHS) in electronic and electrical devices.
Thermodynamic Stability Versus Kinetic Lability of ZnS4 Core
Authors: Picot Delphine , Ohanessian Gilles , Frison Gilles 
Published: April 2010

AbstractDensity Functional Theory and post‐Hartree Fock calculations reveal an unusual energy profile for ZnS and ZnN bond dissociation reactions in several [Zn(SR)4]2− and [Zn(Im)(SR)3]− complexes. The ZnS bond dissociation in tetrathiolate dianions, which is highly exothermic in the gas phase, proceeds through a late transition state which can be rationalized on the basis of an avoided crossing resulting from Coulomb repulsion between the anionic fragments and ligand‐to‐metal charge‐transfer in the [Zn(SR)4]2− complexes. When solvation models for water, DMSO, or acetonitrile are included, some complexes become stable while others are metastable, so this constitutes the first theoretical model which is in full agreement with the experimental data for various [Zn(SR)4]2−, [Zn(SR)3]−, and [Zn(Im)(SR)3]− complexes. The analysis given here indicates that the Zn(Cys)4 and Zn(His)(Cys)3 cores of numerous proteins are metastable with respect to ZnS and ZnN bond dissociation, respectively. This is consistent with the kinetic lability at the zinc‐centers and illustrates that in nature, thermodynamic stability is imparted upon the zinc cores by the protein environment.
Modular Synthesis of Polybenzo[b]silole Compounds for Hole‐Blocking Material in Phosphorescent Organic Light Emitting Diodes
Authors: Ilies Laurean , Sato Yoshiharu , Mitsui Chikahiko , Tsuji Hayato , Nakamura Eiichi 
Published: April 2010

AbstractA diversity‐oriented synthetic strategy allowed us to design a series of conjugated molecules containing multiple benzosilole units that can be utilized as efficient hole‐blocking materials for phosphorescent organic light emitting diodes (OLEDs). Some of these compounds showed a performance surpassing that of the current standard, bathocuproine. The new compounds were easily synthesized in a modular fashion from a previously reported 3‐stannyl benzosilole building unit. Studies on the properties of these compounds in solution and in the solid state indicate that they possess high electron affinity, high ionization potential, and form stable amorphous films that show high electron‐drift mobility. The correlation between their molecular properties and the efficiency of the OLED device performance is also investigated.
Recovering Ga(III) from coordination complexes using pyridine 2,6‐dicarboxylic acid chelation ion chromatography
Authors: Staff K. , Brown M.B. , Hider R.C. , Kong X.L. , Friden P. , Jones S.A. 
Published: April 2010

AbstractIon exchange chelation chromatography is an effective means to extract metals from coordination complexes and biological samples; however there is a lack of data to verify the nature of metal complexes that can be successfully analysed using such a procedure. The aim of this study was to assess the capability of pyridine 2,6‐dicarboxylic acid (PDCA) to extract and quantify Ga(III) from a range of environments using standard liquid chromatography apparatus. The PDCA chelation method generated a single Ga(III) peak with a retention time of 2.55 ± 0.02 min, a precision of <2% and a limit of detection of 110 μM. Ga(III) hydroxide complexes (highest stability constant 15.66) were used to successfully cross‐validate the chelation method with inductively coupled plasma mass spectrometry. The PDCA assay extracted 96.9 ± 1.2% of the spiked Ga(III) from porcine mucus and 100.7 ± 2.7% from a citrate complex (stability constant 10.02), but onlyca50% from an EDTA complex (stability constant 22.01). These data suggest that PDCA chelation can be considered a suitable alternative to inductively coupled plasma mass spectrometry for Ga(III) quantification from all but the most strongly bound coordinated complexes i.e. a stability constant of <15. Copyright © 2010 John Wiley & Sons, Ltd.
Chiral separation of the β2‐sympathomimetic fenoterol by HPLC and capillary zone electrophoresis for pharmacokinetic studies
Authors: Ullrich Thomas , Wesenberg Dirk , Bleuel Corinna , Krauss Gerd‐Joachim , Schmid Martin G. , Weiss Michael , Gübitz Gerald 
Published: April 2010

AbstractThe development of methods for the separation of the enantiomers of fenoterol by chiral HPLC and capillary zone electrophoresis (CZE) is described. For the HPLC separation precolumn fluorescence derivatization with naphthyl isocyanate was applied. The resulting urea derivatives were resolved on a cellulose tris(3,5‐dimethylphenylcarbamate)‐coated silica gel column employing a column switching procedure. Detection was carried out fluorimetrically with a detection limit in the low ng/mL range. The method was adapted to the determination of fenoterol enantiomers in rat heart perfusates using liquid–liquid extraction. As an alternative a CE method was used for the direct separation of fenoterol enantiomers comparing different cyclodextrin derivatives as chiral selectors. Copyright © 2010 John Wiley & Sons, Ltd.
Identification of Adducts Formed in the Reactions of Malonaldehyde–glyoxal and Malonaldehyde–methylglyoxal with Adenosine and Calf Thymus DNA
Authors: Pluskota‐Karwatka Donata , Pawłowicz Agnieszka J. , Bruszyńska Magdalena , Greszkiewicz Aleksandra , Latajka Rafał , Kronberg Leif 
Published: April 2010

AbstractThe reactions of adenosine with malonaldehyde and glyoxal, and with malonaldehyde and methylglyoxal resulted in the formation of one malonaldehyde–glyoxal and one malonaldehyde–methylglyoxal conjugate adduct, respectively. These adducts were isolated and purified by reversed‐phase liquid chromatography, and structurally characterized by UV, 1H‐ and 13C‐NMR spectroscopy, and mass spectrometry. The malonaldehyde–glyoxal adduct was identified as 8‐(diformylmethyl)‐3‐(β‐D‐ribofuranosyl)imidazo[2,1‐i]purine (M1Gx‐A), while the malonaldehyde–methylglyoxal one as 8‐(diformylmethyl)‐7‐methyl‐3‐(β‐D‐ribofuranosyl)imidazo[2,1‐i]purine (M1MGx‐A). Both adducts were also observed in calf thymus DNA when incubated in the respective aldehydes under physiological pH and temperature. Moreover, in the reaction of methylglyoxal and malonaldehyde with adenosine, an additional adduct was formed. This adduct was found to consist of one unit derived from methylglyoxal and one unit from formaldehyde. The adduct was identified as N6‐(2,3‐dihydroxy‐2‐methylpropanoyl)‐9‐(β‐D‐ribofuranosyl)purine (MGxFA‐A). Formaldehyde was found to originate from the commercial methylglyoxal in which it was present as an impurity.
Antimycobacterial Metabolites from Plectranthus: Royleanone Derivatives against Mycobacterium tuberculosis Strains
Authors: Rijo Patrícia , Simões M. Fátima , Francisco A. Paula , Rojas Rosario , Gilman Robert H. , Vaisberg Abraham J. , Rodríguez Benjamín , Moiteiro Cristina 
Published: April 2010

AbstractThe antimycobacterial activities of eight diterpenes, 1–8, isolated previously from Plectranthus and eleven esters, 9–19, of 7α‐acetoxy‐6β,12‐dihydroxyabieta‐8,12‐diene‐11,14‐dione (5) were evaluated against the MTB strains H37Rv and MDR. Only diterpenoids with a quinone framework revealed anti‐MTB activity. Abietane 5 and its 6,12‐dibenzoyl, 12‐methoxybenzoyl, 12‐chlorobenzoyl, and 12‐nitrobenzoyl esters, 9, 11, 12, and 13, respectively, showed potent activities against the MDR strain with MIC values between 3.12 and 0.39 μg/ml. Cytotoxic activities towards 3T3 and Vero cells were also evaluated. Compound 11, with the best selectivity index, may be a suitable lead for further chemical modifications. The complete structural elucidation of the new esters, 9–14, 16, 18, and 19, as well as the NMR data of known derivatives 15 and 17 are reported.
Chemical Composition and Antimicrobial Activity of the Essential Oils from New Caledonian Citrus macroptera and Citrus hystrix
Authors: Waikedre Jean , Dugay Annabelle , Barrachina Isabel , Herrenknecht Christine , Cabalion Pierre , Fournet Alain 
Published: April 2010

AbstractThe essential oils from the leaves of Citrus macroptera and C. hystrix, collected in New Caledonia, have been analyzed by gas chromatography/mass spectrometry (GC/MS) and evaluated for their antimicrobial activity. A total of 35 and 38 constituents were identified, representing 99.1 and 89.0% of the essential oils, respectively. Both essential oils were rich in monoterpenes (96.1 and 87.0%, resp.), with β‐pinene as major component (33.3 and 10.9%, resp.), and poor in limonene (2.4 and 4.7%, resp.). Other main components of C. macroptera oil were α‐pinene (25.3%), p‐cimene (17.6%), (E)‐β‐ocimene (6.7%), and sabinene (4.8%). The essential oil of C. hystrix was characterized by high contents of terpinen‐4‐ol (13.0%), α‐terpineol (7.6%), 1,8‐cineole (6.4%), and citronellol (6.0%). The antimicrobial activity was evaluated against five bacteria and five fungi strains. Both oils were inactive against bacteria. However, the C. macroptera leaf oil exhibited a pronounced activity against Trichophyton mentagrophytes var. interdigitale, with a minimal‐inhibitory concentration (MIC) of 12.5 μg/ml.
Selenium Derivatization of Nucleic Acids for X‐Ray Crystal‐Structure and Function Studies
Authors: Sheng Jia , Huang Zhen 
Published: April 2010

AbstractIt is estimated that over two thirds of all new crystal structures of proteins are determined via the protein selenium derivatization (selenomethionine (Se‐Met) strategy). This selenium derivatization strategy via MAD (multi‐wavelength anomalous dispersion) phasing has revolutionized protein X‐ray crystallography. Through our pioneer research, similarly, Se has also been successfully incorporated into nucleic acids to facilitate the X‐ray crystal‐structure and function studies of nucleic acids. Currently, Se has been stably introduced into nucleic acids by replacing nucleotide O‐atom at the positions 2′, 4′, 5′, and in nucleobases and non‐bridging phosphates. The Se derivatization of nucleic acids can be achieved through solid‐phase chemical synthesis and enzymatic methods, and the Se‐derivatized nucleic acids (SeNA) can be easily purified by HPLC, FPLC, and gel electrophoresis to obtain high purity. It has also been demonstrated that the Se derivatization of nucleic acids facilitates the phase determination via MAD phasing without significant perturbation. A growing number of structures of DNAs, RNAs, and protein–nucleic acid complexes have been determined by the Se derivatization and MAD phasing. Furthermore, it was observed that the Se derivatization can facilitate crystallization, especially when it is introduced to the 2′‐position. In addition, this novel derivatization strategy has many advantages over the conventional halogen derivatization, such as more choices of the modification sites via the atom‐specific substitution of the nucleotide O‐atom, better stability under X‐ray radiation, and structure isomorphism. Therefore, our Se‐derivatization strategy has great potentials to provide rational solutions for both phase determination and high‐quality crystal growth in nucleic‐acid crystallography. Moreover, the Se derivatization generates the nucleic acids with many new properties and creates a new paradigm of nucleic acids. This review summarizes the recent developments of the atomic site‐specific Se derivatization of nucleic acids for structure determination and function study. Several applications of this Se‐derivatization strategy in nucleic acid and protein research are also described in this review.
Blast Furnace Slag of a Ferrosilicon Firm in Aswan Governorate, Upper Egypt, as an Adsorbent for the Removal of Merocyanine Dye from Its Aqueous Solution
Authors: Taha Gharib Mahmoud , Mosaed Taghreed Mahmoud 
Published: April 2010

AbstractThe adsorption potential of the blast furnace slag of a ferrosilicon firm in Aswan Governorate, Egypt, to decolorize aqueous solutions of 3‐methyl‐1‐phenylpyrazol‐5‐one 4[2] merocyanine dye (1) was investigated at room temperature. The influence of the solution pH, the quantity of adsorbent, the initial concentration of 1, and the applied contact time were studied with the batch technique. The maximum percentage of removal of 1 was observed at pH 4. The adsorption data were better fitted by the Freundlich than by the Langmuir adsorption isotherm model, confirming the formation of monolayers of 1 on the adsorbent surface. Kinetic rate constants and the transient behavior at different initial concentrations of 1 were determined with both the Lagergren pseudo‐first‐order and the Ho and McKay pseudo‐second‐order kinetic models. The calculated kinetic parameters revealed that the adsorption of 1 on blast furnace slag followed a second‐order chemisorption process.
Effect of Pedoclimatic Conditions on the Chemical Composition of the Sigoise Olive Cultivar
Authors: Dabbou Samia , Sifi Samira , Rjiba Imed , Esposto Sonia , Taticchi Agnese , Servili Maurizio , Montedoro Gian Francesco , Hammami Mohamed 
Published: April 2010

AbstractThe present work focused on the quality and the chemical composition of monovarietal virgin olive oil from the Sigoise variety grown in two different locations in Tunisia, viz., a sub‐humid zone (Béjaoua, Tunis) and an arid zone (Boughrara, Sfax). In addition to the quality characteristics (acidity, peroxide value, and the spectrophotometric indices K232 and K270) and the chemical composition (content of fatty acids, antioxidants, and volatile compounds) of the oil, the fruit characteristics of the olives were studied. Except for the content of the majority of the fatty acids, there were significant differences observed in the oil composition of olives that were cultivated in different locations. The content of total phenols and lipoxygenase (LOX) oxidation products was higher for olives grown at the higher altitude, whereas that of α‐tocopherol, carotenes, and chlorophylls was higher for olives from the Boughrara region (lower altitude). Moreover, olives produced at the higher altitude showed a higher ripeness index and oil content than those cultivated at the lower altitude.
Variation in Volatile Leaf Oils of 13 Eucalyptus Species Harvested from Souinet Arboreta (Tunisia)
Authors: Elaissi Ameur , Marzouki Hanène , Medini Hanène , Larbi Khouja Mohamed , Farhat Farhat , Lynene Fréderic , Harzallah‐Skhiri Fethia , Chemli Rachid 
Published: April 2010

AbstractHydrodistillation of the dried leaves of 13 species of the genus Eucalyptus L' Hér., viz., E. bicostata Maiden, Blakely & Simmonds, E. cinerea F. Muell. ex Benth., E. exerta F. Muell., E. gigantea Hook. f., E. gunnii Hook. f., E. macarthurii Deane & Maiden., E. macrorrhyncha F. Muell., E. maidenii F. Muell., E. odorata Behr., E. pauciflora Sieber ex Sprengel, E. sideroxylon A. Cunn. ex Woolls, E. tereticornis Sm., and E. viminalis Labill., harvested from Souinet arboreta (region of Ain Draaham, north of Tunisia) in June 2006, afforded essential oils in yields varying from 0.5±0.2 to 3.9±0.4%, dependent on the species. E. cinerea and E. exerta provided the highest and the lowest percentage of essential oil amongst all the species examined, respectively. Analysis by GC (RI) and GC/MS allowed the identification of 142 components, representing 81.5 to 98.9% of the total oil. The contents of the different samples varied according to the species. The main components were 1,8‐cineole (1), followed by cryptone, spathulenol (4), p‐cymene (2), viridiflorol (6), globulol (7), β‐eudesmol, α‐terpineol (5), limonene (8), D‐piperitone, α‐pinene (3), cuminal, and γ‐eudesmol. The principal component and the hierarchical cluster analyses separated the 13 Eucalyptus leaf essential oils into three groups, each constituting a chemotype.
Prenylated Benzophenone Peroxide Derivatives from Hypericum sampsonii
Authors: Xiao Zhi Yong , Zeng Yi Han , Mu Qing , Shiu Winnie Ka Po , Gibbons Simon 
Published: April 2010

AbstractTwo new prenylated benzophenone peroxide derivatives, peroxysampsones A and B (1 and 2, resp.), together with a known compound, plukenetione C (3), were isolated from the roots of the Chinese medicinal plant Hypericum sampsonii, and their structures were elucidated by detailed spectral analysis. These compounds are the unusual peroxides of polyprenylated benzophenone derivatives, containing the unique caged moiety of 4,5‐dioxatetracyclo[9.3.1.19,13.01,7]hexadecane‐12,14,15‐trione. In the biological test, peroxysampsone A (1) showed comparable activity with norfloxacin against a NorA over‐expressing multidrug‐resistant (MDR) strain of Staphylococcus aureus SA‐1199B.
Quantitative Comparison of Ginsenosides and Polyacetylenes in Wild and Cultivated American Ginseng
Authors: Wang Jing‐Rong , Leung Chiu‐Yin , Ho Hing‐Man , Chai Stella , Yau Lee‐Fong , Zhao Zhong‐Zhen , Jiang Zhi‐Hong 
Published: April 2010

AbstractQuantitative comparison of seven ginsenosides in wild and cultivated American ginseng revealed that the Rg1/Rd ratio presented a significantly large difference between cultivated and type‐I (one of the defined chemotypes) wild American ginseng, facilitating this ratio as a characteristic marker for differentiating these two groups. Similarly, the ratio (Rg1+Re)/Rd, and the ratio of protopanaxatriol (PPT)‐type ginsenosides to protopanaxadiol (PPD)‐type ginsenosides showed a large difference between these two groups. On the other hand, type‐II wild samples were found to have high Rg1/Rb1 and Rg1/Re ratios and low panaxydol/panaxynol ratio, which is entirely different from Type‐I American ginseng, but is very similar to that of Asian ginseng. This not only suggests that the chemotype should be taken into consideration properly when using these parameters for differentiating American and Asian ginseng, but also indicates that type‐II wild American ginseng may have distinct pharmacological activities and therapeutic effects.