bluuebunny/crossref_metadata_2025_split huggingface dataset:
Preparation of antibacterial chito‐oligosaccharide by altering the degree of deacetylation of β‐chitosan in a Trichoderma harzianum chitinase‐hydrolysing process
Authors: Lin Shih‐Bin , Chen Shan‐He , Peng Kou‐Cheng 
Published: November 2008

AbstractBACKGROUND: Chito‐oligosaccharide (COS) is generally known to possess many specific biological functions, especially antibacterial activity, depending on its size. To prepare a specific size range of COS, however, has proved difficult. The aim of this study was to establish a method for preparing a specific size range of antibacterially active COS by adjusting the degree of deacetylation (DD) of β‐chitosan in a Trichoderma harzianum chitinase‐hydrolysing process.RESULTS: The molecular weight spectrum, elucidated by viscosity‐average molecular weight, high‐performance liquid chromatography and thin layer chromatography, of COS in chitosan hydrolysate was significantly related to the DD of its original chitosan. Compared with the original form, COS produced at 90% DD showed superior activity against most Gram‐negative bacteria tested, with a minimum inhibition concentration (MIC) ranging from 55 ± 27 to 200 ± 122 µ g mL−1. Conversely, most Gram‐positive strains tested were less sensitive to COS (MIC > 880 ± 438 µ g mL−1) than to its original form. Among the Gram‐positive strains, Staphylococcus xylosus was the only exception in that it showed a high susceptibility to COS and had an MIC as low as 45 ± 11 µ g mL−1.CONCLUSION: The results indicate that the production of a specific size range of COS product is possible by altering the DD of chitosan in the chitinase‐catalysed process. To produce various sizes of COS for versatile biological functions, as seen in this study to inhibit various types of bacteria, is made possible in this established process. Copyright © 2008 Society of Chemical Industry
Aflatoxin contamination of consumer milk caused by contaminated rice by‐products in compound cattle feed
Authors: Nordkvist Erik , Stepinska Anna , Häggblom Per 
Published: November 2008

AbstractBACKGROUND: Elevated levels of aflatoxin M1 were observed in routine checks of consumer milk in southern Sweden in early 2006. A trace‐back study revealed contaminated milk from several farms, and a total of 68 farms were banned from delivering milk to dairies for shorter or longer periods. The maximum level of aflatoxin M1 in a single sample from an individual farm was 257 ng kg−1 fresh milk.RESULTS: Aflatoxin analyses of commercial compound feed revealed that the contamination originated from the ingredient rice feed meal, a by‐product from the preparation of Basmati rice for human consumption. Up to 56 µg kg−1 of aflatoxin B1 was found in rice feed meal at one feed mill.CONCLUSION: The present example shows that an aflatoxin‐contaminated minor feed ingredient included at less than 10% (w/w) of compound cattle feed can significantly contaminate the milk produced. This emphasises the need for effective monitoring of the feed chain of food‐producing animals in order to prevent food contamination. Copyright © 2008 Society of Chemical Industry
Plasma Polymer Surfaces Compatible with a CMOS Process for Direct Covalent Enzyme Immobilization
Authors: Yin Yongbai , Nosworthy Neil J. , Gong Bill , Bax Dan , Kondyurin Alexy , McKenzie David R. , Bilek Marcela M. M. 
Published: November 2008

AbstractPlasma polymerized surfaces, prepared using a CMOS compatible plasma enhanced chemical vapor polymerization technique, are found to covalently immobilize enzymes without the need for intermediate chemical linker groups. The polymerized surfaces are smooth, strongly adherent to substrates, and have a long shelf life for storage. After incubation with enzymes, a densely packed monolayer is attached. We report the effects of both oxygen etching and annealing post‐processing showing that they can be implemented so as not to affect the enzyme binding performance. The fully compatible polymerization method with CMOS device manufacture processes is a potential candidate for integration into nano‐CMOS biochemical sensors for direct immobilization of enzymes.magnified image
QSAR Analysis of Antimicrobial Activity of 4‐thiazolidone Derivatives
Authors: Artemenko Anatoliy G. , Muratov Eugene N. , Atamanyuk Dmytro V. , Kuz'min Victor E. , Hromov Alexander I. , Kutsyk Roman V. , Lesyk Roman B. 
Published: November 2008

AbstractThe influence of molecular structure of 4‐thiazolidone derivatives (about 70 compounds) on their antimicrobial activity has been investigated by QSAR approach based on Simplex Representation of Molecular Structure (SiRMS). This method is characterized by the absence of molecular alignment problem as well as by taking into account the different atom characteristics (partial charge, lipophilicity, etc) and the possibility of drug design. The following micro‐organisms were used as reference cultures: Candida albicans S, Citrobacter freundii, Klebsiella pneumoniae, Pseudomonas aeruginosa (R and S strains) and Staphylococcus aureus MSSA. Statistical characteristics of QSAR models obtained by Partial Least Squares (PLS) method are rather good (R2=0.843–0.989, Q2=0.679–0.864, R2test=0.744–0.943). Y‐scrambling test shows the possibility of chance correlations for equations developed for C. freundii and K. pneumonia. These two cultures were excluded from subsequent analysis. The molecular fragments promoting/interfering with antimicrobial activity and degree of their influence on the activities have been determined. Thus, naphthalene‐substituted fragment (irrespective to its location within the molecule) decreases the antimicrobial activities significantly. The requirements to molecular design were formulated; e.g. highly active compounds must contain indole fragment. In addition, the influence of heterocyclic system evolution on antimicrobial properties of 4‐thiazolidones derivatives was demonstrated. The important role of electrostatic characteristics of their molecular structure was also shown. The compounds with the highest predicted values of antimicrobial activities against several cultures were chosen as a result of virtual screening.
Acute Toxicity of Substituted 2‐(1H‐pyrazol‐1‐yl)acetanilides and Related Commercially Available Local Anesthetics Toward Mice. A GRIND/ALMOND‐Based 3‐D QSAR Study
Authors: Drakulić Branko J. , Zalaru Christina , Iovu Mircea 
Published: November 2008

AbstractAlignment‐free three‐dimensional quantitative structure–toxicity relationship models, developed on the basis of GRid INdependent Descriptors (GRIND), on acute toxicity data obtained by (i) oral administration of 25 pyrazolylacetanilides, and (ii) intravenous administration of 15 commercially available Local Anesthetics (LAs) to mice was reported. The most favorable interaction regions extracted from molecular interaction fields obtained with HBA, HBD, hydrophobic, and shape probes were correlated with toxicity data expressed as log[1/(LD50)] by partial Least Square Analysis (PLS). Variable selection was done by fractional factorial design. The best PLS models for set (i) comprises 3LV with r2=0.95 and q2=0.72; for set (ii) comprises 2LV with r2=0.95 and q2=0.58. Internal cross‐validation was done by using three random groups of compounds for each set. External predictivity of the second model was checked by a test set consists of eight structurally diverse compounds. The PLS model related to orally administrated set of compounds was compared with the corresponding one related to intravenously administrate drugs. Variables having high impact on each model, positively or negatively correlated with toxicities, were discussed and an attempt was made to link those variables with calculated ADME related properties of compounds, as well as with literature data that describes probable interaction of LA drugs with the homology modeled voltage‐gated sodium channels. According to the best of our knowledge this is first reported study that use GRIND methodology in structure–toxicity relationships on whole animals.
Theoretical Prediction of Antiproliferative Activity against Murine Leukemia Tumor Cell Line (L1210). 3D‐Morse Descriptor and its Application in Computational Chemistry
Authors: Saíz‐Urra Liane , Pérez‐Castillo Yunierkis , Pérez González Maykel , Molina Ruiz Reinaldo , Cordeiro M. Natália D. S. , Rodríguez‐Borges J. Enrique , García‐Mera Xerardo 
Published: November 2008

AbstractCancer is among the top ten causes of death in the world but in spite of the efforts of the pharmaceutical companies and many governmental organizations, new and more effective drugs are urgently needed. Computer‐assisted studies have been widely used to predict anticancer activity taking into account different molecular descriptors, statistical techniques, cell lines, and datasets of congeneric and non‐congeneric compounds.
Resonance energies and fusion rates of mass‐nonsymmetric dtμ* molecule
Authors: Gheisari Rouhollah 
Published: November 2008

AbstractSeveral resonances in the molecular spectrum of the exotic dtμ* ion are obtained. We present a theoretical formulation for its energy levels together with the numerical calculations for the nuclear fusion rates. The calculations are performed with the coupled rearrangement channel method, but with a set of functions alternative to others. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009
Development of consistent buckling curves for torsional and lateral‐torsional buckling
Authors: Taras Andreas , Greiner Richard 
Published: November 2008

AbstractThe stability design of beams and columns for lateral‐torsional and torsional buckling is generally treated in the new Eurocode 3‐1‐1 [1] by using the same buckling curves used for flexural buckling. These buckling curves are expressed mathematically in terms of a function χ($ \bar \lambda $), which was derived in [2] and [3] by combining a first‐yield strength criterion with a second‐order analysis of a geometrically imperfect column. Since the basic idea of this approach was originally presented by Ayrton and Perry [4], their names are often quoted in reference to this type of representation of buckling curves.In this paper, analytical Ayrton‐Perry‐type formulae are developed for the lateral‐torsional and torsional buckling modes of profiles with doubly symmetrical open I‐sections. The similarities and differences to the flexural buckling mode are highlighted.As a first step, the analytical background of the current code regulations is discussed and compared to the actual behaviour in lateral‐torsional and torsional buckling of open sections as shown by geometrically and materially non‐linear FEM calculations (GMNIA). Then, both the numerically derived buckling curves and the current code regulations (Eurocode 3) for these modes are compared to the Ayrton‐Perry‐type formulae developed.
Performance of drywall shear walls: UC Irvine and CSU San Jose tests
Authors: Hart Gary C. , Hortacsu Ayse , Simsir Can , Jain Anurag 
Published: November 2008

AbstractA wealth of data has become available since 2001 about the performance of drywall shear walls under cyclic loading. Drywalls and stucco are the only earthquake lateral force‐resisting system in many existing residential buildings, especially single‐family homes built in the 1970s and earlier. This paper takes a closer look at the actual laboratory cycle‐by‐cycle data from three test programs and uses them to clarify the meaning of significant damage in regard to gypsum‐sheathed shear walls. This paper can be viewed as an extension of the valuable information in the reports by the original authors with a focus on the interpretation and use of the test data for the evaluation of damage to existing wood‐frame buildings. Analysis of the data considers the strength loss observed between the initial and later cycles when the wall is loaded to a certain displacement and shows that a loss of strength does occur. In this regard the paper can also be valuable to others working on performance based design development. The last section of the paper also considers the case where a wall might be repaired after the first cyclic loading protocol and loaded again after the repairs. Copyright © 2008 John Wiley & Sons, Ltd.
Desulfuration and Cyclization of (Z)‐2‐[Amino(pyridine‐2‐yl)methylene]‐ hydrazonecarbothioamide in the Presence of Manganese(II)
Authors: Castiñeiras Alfonso , García‐Santos Isabel 
Published: November 2008

AbstractThe reaction of (Z)‐2‐[amino(pyridine‐2‐yl)methylene]hydrazonecarbothioamide (HAm4DH) with Mn(ClO4)2·6H2O afforded different mononuclear or polynuclear manganese(II) complexes, the nature of which apparently depended on the solvent used. For example, in ethanol a compound of formula [Mn(HAm4DH)2](ClO4)2 (1) was obtained, where HAm4DH coordinates as a common tridentate NNS donor, but the [Mn(bpy)2(NCS)2] complex (2) (bpy = 2,2'‐bipyridine) has also been obtained – probably due to C–N bond cleavage of the thiosemicarbazone. Nevertheless, in a basic aqueous medium [Mn(bpy)3](ClO4)2·0.5bpy (3) is formed and there is structural evidence for chemical transformations of the thiosemicarbazone promoted by MnII. Thus, the sulfate in {[Mn(py)4Mn(py)2(H2O)2(μ‐SO4)2]·4H2O}n (4) or sulfate and cyclooctasulfur in [Mn(pta)2(pdo)]4(SO4)2·4H2O·S8] (5), where pta is 3‐(pyridin‐2‐yl)‐1,2,4‐triazol‐5‐amine and pdo is (2R,4R/2S,4S)‐pentane‐2,4‐diolato, arise from the desulfuration and oxidation of the thiosemicarbazone ligand. The structures of complexes 2 to 5 were established by single‐crystal X‐ray diffraction. The formation of pta is the result of the oxidative cyclization of HAm4DH. In the polynuclear complex 4, the sulfate acts as an (O,O') bridge between alternating Mn(py)2(H2O)2 and Mn(py)4 centers. In the tetranuclear complex 5, pta acts as a bischelating ligand through the N‐pyridine and N‐triazole, and pdo act as a bridge between two manganese atoms. It is also noteworthy that in complexes 4 and 5 hydrogen bonds give rise to different self‐assembly behaviour that leads to complicated supramolecular structures.
Formation of Crystalline CdSe Particles from a Single‐Source‐Precursor according to Ostwald's Rule
Authors: Erk Christoph , Rohner Christian , Schlecht Sabine 
Published: November 2008

AbstractThe formation of crystalline CdSe particles in the thermal degradation of Cd(SePh)2·TMEDA (TMEDA = tetramethylethylenediamine) as a single‐source‐precursor was investigated by in‐situ powder X‐ray diffraction. It was shown that the primary grains were formed in the cubic zinc blende modification. After an increase in particle size by further annealing a phase transition to the thermodynamically favored hexagonal wurtzite type was detected. This behaviour indicates that, according to Ostwald's rule, the primary grains consist of the less stable polymorph due to the lower activation barrier of its formation. When the volume energy of the particles gets dominant over the surface energy, the metastable form is transformed and the system adopts the modification of lowest energy.
Burn injuries during pregnancy in Iran
Authors: Karimi Hamid , Momeni Mahnoush , Momeni Mazdak , Rahbar Hossein 
Published: November 2008

AbstractObjectiveTo report on maternal and fetal outcome in 53 pregnant women seen at a referral burn center.MethodsPossible links between outcome and maternal age, level of education, marital status, percentage of total body surface area (TBSA) burned, inhalation injury, source and intentionality of the burn, and trimester of pregnancy at the time of the burn were assessed.ResultsOf 5497 women, 53 (1.3%) were pregnant at the time of admission. Maternal and fetal deaths occurred at significantly higher rates in cases of inhalation injury (P = 0.001). The mean percentage of TBSA burned was significantly higher in cases of maternal or fetal death (P < 0.001 for both), and when the burn has a suicidal intent (P = 0.006). The maternal and fetal mortality rates were also higher when the burn was suicidal (P = 0.001 and P = 0.005).ConclusionInhalation injury, suicidal burn injury, and percentage of TBSA burned were correlated with a higher maternal and fetal mortality.
Modelling the lactation curve of dairy cows using the differentials of growth functions
Authors: NASRI M. H. FATHI , FRANCE J. , ODONGO N. E. , LOPEZ S. , BANNINK A. , KEBREAB E. 
Published: November 2008

SUMMARYDescriptions of entire lactations were investigated using six mathematical equations, comprising the differentials of four growth functions (logistic, Gompertz, Schumacher and Morgan) and two other equations (Wood and Dijkstra). The data contained monthly milk yield records from 70 first, 70 second and 75 third parity Iranian Holstein cows. Indicators of fit were model behaviour, statistical evaluation and biologically meaningful parameter estimates and lactation features. Analysis of variance with equation, parity and their interaction as factors and with cows as replicates was performed to compare goodness of fit of the equations. The interaction of equation and parity was not significant for any statistics, which showed that there was no tendency for one equation to fit a given parity better than other equations. Although model behaviour analysis showed better performance of growth functions than the Wood and Dijkstra equations in fitting the individual lactation curves, statistical evaluation revealed that there was no significant difference between the goodness of fit of the different equations. Evaluation of lactation features showed that the Dijkstra equation was able to estimate the initial milk yield and peak yield more accurately than the other equations. Overall evaluation of the different equations demonstrated the potential of the differentials of simple empirical growth functions used in the current study as equations for fitting monthly milk records of Holstein dairy cattle.
Phosphatidylserine surface expression and integrin αIIbβ3 activity on thrombin/convulxin stimulated platelets/particles of different sizes
Authors: Rukoyatkina Natalia , Begonja Antonija J. , Geiger Jörg , Eigenthaler Martin , Walter Ulrich , Gambaryan Stepan 
Published: November 2008

SummaryPlatelets stimulated by a combination of thrombin/convulxin have been shown to develop two to three populations characterized by different phosphatidylserine (PS) surface expression and integrin αIIbβ3 activity. To determine how these markers are distributed on the surface of platelets/particles, we studied Annexin V and PAC‐1 binding to platelets/particles of different sizes by flow cytometry analysis and evaluated influences of calpain and caspase inhibitors on thrombin/convulxin‐activated platelets. Analysed platelets/particles were divided by their sizes, according to the standard size beads, into seven populations from 0·37 to 4·8 μm. PAC‐1 binding/μm2 was almost equal in platelets/particles ranging from 1·2 to 4·8 μm and was significantly lower on smaller‐sized particles sizes (0·37–0·7 μm). PS surface exposure/μm2 was high in the particles of 0·37–1·2 μm and very low in platelets (2·6–4·8 μm). Upon thrombin/convulxin stimulation caspase inhibitors prevented microparticle (MP) formation, while a calpain inhibitor stimulated MP formation. It was also shown that stimulated platelets are heterogeneous not only in their ability to activate αIIbβ3 integrin complex and expose PS on their surface, but also in the distribution of activation markers, which strongly depends on platelet/particle size and that platelets/particles of different sizes provide different responses to the same stimulus.
Expression and Localization of Gap Junctional Connexins 26 and 43 in Bovine Periovulatory Follicles and in Corpus Luteum During Different Functional Stages of Oestrous Cycle and Pregnancy
Authors: Berisha B , Bridger P , Toth A , Kliem H , Meyer HHD , Schams D , Pfarrer C 
Published: November 2008

ContentsThe aim of this study was to characterize the regulation of connexins (Cx26 and Cx43) in the bovine ovary (experiment 1–3). Experiment 1: ovaries containing preovulatory follicles or corpora lutea (CL) were collected at 0, 4, 10, 20, 25 (follicles) and 60 h (CL) relative to injection of GnRH. Experiment 2: CL were assigned to the following stages: days 1–2, 3–4, 5–7, 8–12, 13–16, >18 (after regression) of oestrous cycle and of early and late pregnancy (<4 and >4 months). Experiment 3: induced luteolysis, cows on days 8–12 were injected with PGF2α analogue (Cloprostenol), and CL were collected by transvaginal ovariectomy before and 0.5, 2, 4, 12, 24, 48 and 64 h after PGF2α injection. Real‐time RT‐PCR was applied to investigate mRNA expression and immunofluorescence was utilized for protein localization. Cx26 mRNA increased rapidly 4 h after GnRH injection (during LH surge) and decreased afterwards during the whole experimental period. Cx43 mRNA expression decreased continuously after GnRH application. Cx26 mRNA in CL increased significantly in the second part of oestrous cycle and after regression. In contrast, the highest mRNA expression for Cx43 in CL was detected during the early luteal phase. After induced luteolysis the mRNA expression of Cx26 increased significantly at 24 h. As shown by immunofluorescence, Cx26 was predominantly localized in the connective tissue and blood vessels of bovine CL, whereas Cx43 was present in the luteal cells and blood vessels. This resulted in a strong increase of Cx26 expression during the late luteal phase and after luteal regression. Subsequently, Cx43 expression was distinctly decreased after luteal regression. These data suggest that Cx26 and Cx43 are involved in the local cellular mechanisms participating in tissue remodelling during the critical time around periovulation as well as during CL formation (angiogenesis), function and regression in the bovine ovary.
Uterine Expression of Epidermal Growth Factor Family During the Course of Pregnancy in Pigs
Authors: Kim Y‐J , Lee G‐S , Hyun S‐H , Ka H‐H , Choi K‐C , Lee C‐K , Jeung E‐B 
Published: November 2008

ContentsTo stably maintain pregnancy, several genes are expressed in the uterus. In particular, the endometrial expression of genes encoding growth factors appears to play a key role in maternal–foetal communication. The previous studies characterized the endometrial expression kinetics of the genes encoding epidermal growth factor (EGF), its receptor (EGFR), transforming growth factor‐alpha (TGF‐α), amphiregulin (Areg), heparin‐binding (Hb) EGF and calbindin‐D9k (CaBP‐9k) in pigs during implantation. Here, we further characterized the expression patterns of these molecules during the entire porcine pregnancy. Porcine uteri were collected at pregnancy days (PD) 12, 15, 30, 60, 90 and 110 and subjected to RT‐PCR. EGF and EGFR showed similar expression patterns, being highly expressed around implantation and then disappearing. TGF‐α and Areg expression levels rose steadily until they peaked at PD30, after which they gradually decreased to PD12 levels. This Areg mRNA expression pattern was confirmed by real‐time PCR and similar Areg protein expression patterns were observed. Immunohistochemical analysis of PD60 uteri revealed Areg in the glandular and luminal epithelial cells. Hb EGF was steadily expressed throughout the entire pregnancy, while CaBP‐9k was expressed strongly on PD12, and then declined sharply on PD15 before recovering slightly for the remainder of the pregnancy. Thus, the EGF family may play a key role during implantation in pigs. In addition, CaBP‐9k may help to maintain uterine quiescence during pregnancy by sequestering cytoplasmic Ca2+.