bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ablation of de novo DNA methyltransferase Dnmt3a in the nervous system leads to neuromuscular defects and shortened lifespan
Authors: Nguyen Suzanne , Meletis Konstantinos , Fu Dongdong , Jhaveri Sonal , Jaenisch Rudolf 
Published: May 2007

AbstractDNA methylation is an epigenetic mechanism involved in gene regulation and implicated in the functioning of the nervous system. The de novo DNA methyltransferase Dnmt3a is expressed in neurons, but its specific role has not been clarified. Dnmt3a is activated around embryonic day 10.5 in mouse neuronal precursor cells and remains active in postmitotic neurons in the adult. We assessed the role of neuronal Dnmt3a by conditional gene targeting. Mice lacking functional Dnmt3a in the nervous system were born healthy, but degenerated in adulthood and died prematurely. Mutant mice were hypoactive, walked abnormally, and underperformed on tests of neuromuscular function and motor coordination. Loss of Dnmt3a also led to fewer motor neurons in the hypoglossal nucleus and more fragmented endplates in neuromuscular junctions of the diaphragm muscle. Our results implicate a role for Dnmt3a in the neuromuscular control of motor movement. Developmental Dynamics 236:1663–1676, 2007. © 2007 Wiley‐Liss, Inc.
Evolutionary perspectives from development of mesodermal components in the lamprey
Authors: Kusakabe Rie , Kuratani Shigeru 
Published: May 2007

AbstractLampreys, a jawless vertebrate species, lack not only jaws but also several other organs, including ventral migratory muscles shared by gnathostomes. In the lamprey embryo, the mesoderm consists primarily of unsegmented head mesoderm, segmented somites, and yet uncharacterized lateral plate mesoderm, as in gnathostomes. Although the adult lamprey possesses segmented myotomes in the head, the head mesoderm of this animal is primarily unsegmented, similar to that in gnathostomes. In the trunk, the large part of lamprey somites is destined to form myotomes, and the Pax3/7 gene expression domain in the lateral part of somites is suggested to represent a dermomyotome homologue. Lamprey myotomes are not segregated by a horizontal myoseptum, which has been regarded as consistent with the apparent absence of a migratory population of hypaxial muscles shared by gnathostomes. However, recent analysis suggests that lampreys have established the gene regulatory cascade necessary for the ventrally migrating myoblasts, which functions in part during the development of the primordial hypobranchial muscle. There have also been new insights on the developmental cascade of lamprey cartilages, in which the Sox family of transcription factors plays major roles, as in gnathostomes. Thus, mesoderm development in lampreys may represent the ancestral state of gene regulatory mechanisms required for the evolution of the complex and diverse body plan of gnathostomes. Developmental Dynamics 236:2410–2420, 2007. © 2007 Wiley‐Liss, Inc.
DNA Interactions Mediated by Cyclopentadienidoruthenium(II) Complexes Containing Water‐Soluble Phosphanes
Authors: Romerosa Antonio , Saoud Mustapha , Campos‐Malpartida Tatiana , Lidrissi Chaker , Serrano‐Ruiz Manuel , Peruzzini Maurizio , Garrido Jose Antonio , García‐Maroto Federico 
Published: May 2007

AbstractThe water‐soluble ruthenium(II) complexes Na2[RuCpX(mTPPMS)2] [X = Cl (1), I (2)] and Nax[RuCp(mTPPMS)(PR13)(PR23)](OTf)y [PR13 = PR23 = PPh3 (3), PTA (4), x = y = 0; PR13 = mTPPMS, PR23 = PTA (5), x = 1, y = 0; PR13 = mTPPMS, PR23 = mPTA (6), x = y = 0; PR13 = PR23 = mTPPMS (7), x = 2, y = 0; PR13 = PPh3, PR23 = PTA (8), x = y = 0; PR13 = mPTA, PR23 = PPh3 (9), x = 0, y = 1; mTPPMS = Ph2P(3‐OSO2C6H4)–; PTA = 1,3,5‐triaza‐7‐phosphaadamantane; mPTA = N‐methyl‐1,3,5‐triaza‐7‐phosphaadamantane] have been synthesized and characterised by elemental analysis, NMR and IR spectroscopy and crystallographic methods. The X‐ray crystal structure determination of [RuCp(mTPPMS)(PPh3)(PTA)]·2H2O (8·2H2O), which is the first half‐sandwich ruthenium complex bearing three different phosphanes, has also been determined. The binding properties of these new water‐soluble ruthenium complexes towards DNA and the interaction of free mTPPMS with the nucleic acid have been studied using the mobility shift assay, which has shown that both the activity of the ruthenium complexes and the possible mechanism governing the interaction with DNA are strictly dependent on the composition of the complexes.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Functionalization of Vinylspherosilicates by Ruthenium‐Catalyzed Silylative Coupling Reactions
Authors: Waehner Jacek , Marciniec Bogdan , Pawluć Piotr 
Published: May 2007

AbstractHighly effective functionalization of monovinylsiloxy heptaisobutylsilsesquioxane and octavinylspherosilicate of the formula (ViMe2SiO)(iBu)7Si8O12 (1) and (ViMe2SiO)8Si8O12 (2), respectively, with a variety of olefins, by using a Ru(H)(Cl)(CO)(PCy3)2‐catalyzed silylative coupling procedure is reported. The cross‐metathesis reaction catalyzed by a ruthenium–carbene complex does not proceed for this system. Whereas the reaction of 1 and 2 with styrene takes place highly stereo‐ and regioselectively, the respective reaction with 1‐hexene gives a mixture of isomers. However, functionalization of 1 and 2 with vinylic heteroatom‐substituted (N, O, Si) derivatives was found to be highly efficient for the synthesis of spherosilicates with β‐heteroatom vinylic functionalities (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Preparation and Molecular Structures of Stable Bis(germylenes) with Pincer Topology
Authors: Hahn F. Ekkehardt , Zabula Alexander V. , Pape Tania , Hepp Alexander 
Published: May 2007

AbstractBenzannulated N‐heterocyclic bis(germylenes) with pincer ligand topology have been prepared by the reaction of N,N′,N″,N″′‐tetralithiated tetraamines with GeCl2·1,4‐dioxane or by the transamination reaction between a tetraamine and Ge[N(SiMe3)2]2. X‐ray diffraction studies have shown, that the bis(germylenes) exist as monomers in the solid state. Significant intramolecular Ge···Ge and Ge···N interactions have been observed for the lutidine‐bridged bis(germylene). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
System‐justifying ideologies moderate status = competence stereotypes: roles for belief in a just world and social dominance orientation
Authors: Oldmeadow Julian , Fiske Susan T. 
Published: May 2007

AbstractHigh‐status outgroups tend to be stereotyped as competent, while low‐status groups tend to be stereotyped as incompetent. These stereotypes provide legitimacy to hierarchical social systems. However, research to date has tended to focus on the socio‐structural correlates and cross‐cultural stability of these stereotypes, emphasising universality over malleability. The current research demonstrates that, although strong, the association between status and competence, but not status and warmth, is moderated by ideological beliefs and attitudes towards inequality. In two studies, participants high in belief in a just world (BJW) or social dominance orientation (SDO) were more likely than those low in BJW or SDO to view a high‐status target as more competent than a low‐status target. Findings support the view that status stereotypes justify social inequalities, and demonstrate that they are sensitive to ideological orientations. Implications for theory and research on status and power stereotypes are discussed. Copyright © 2007 John Wiley & Sons, Ltd.
Universal method for synthesis of artificial gel antibodies by the imprinting approach combined with a unique electrophoresis technique for detection of minute structural differences of proteins, viruses and cells (bacteria). Ib. Gel antibodies against proteins (hemoglobins)
Authors: Takátsy Anikó , Végvári Ákos , Hjertén Stellan , Kilár Ferenc 
Published: May 2007

AbstractUsing the molecular imprinting approach, we have shown that polyacrylamide‐based artificial antibodies against human and bovine hemoglobin have a very high selectivity, as revealed by the free‐zone electrophoresis in a revolving capillary. By the same technique we have previously synthesized gel antibodies not only against proteins but also against viruses and bacteria. The synthesis is thus universal, i.e., it has the great advantage of not requiring a modification – or only a slight one – for each particular antigen. The combination synthesis of artificial gel antibodies and electrophoretic analysis reveals small discrepancies in shape and chemical composition not only of proteins, as shown here and in paper Ia, but also of viruses and bacteria, to be illustrated in papers II and III in this series. Upon rehydration, the freeze‐dried gel antibodies, selective for human hemoglobin, regain their selectivity. The gel antibodies can repeatedly be used following the removal of the antigen (protein in this study) from the complex gel antibody/antigen by an SDS washing or an enzymatic degradation.
CEC separation of insect oostatic peptides using a strong‐cation‐exchange stationary phase
Authors: Rocco Anna , Aturki Zeineb , D'Orazio Giovanni , Fanali Salvatore , Šolínová Veronika , Hlaváček Jan , Kašička Václav 
Published: May 2007

AbstractThe separation of several insect oostatic peptides (IOPs) was achieved by using CEC with a strong‐cation‐exchange (SCX) stationary phase in the fused‐silica capillary column of 75 μm id. The effect of organic modifier, ionic strength, buffer pH, applied voltage, and temperature on peptides' resolution was evaluated. Baseline separation of the studied IOPs was achieved using a mobile phase containing 100 mM pH 2.3 sodium phosphate buffer/water/ACN (10:20:70 v/v/v). In order to reduce the analysis time, experiments were performed in the short side mode where the stationary phase was packed for 7 cm only. The selection of the experimental parameters strongly influenced the retention time, resolution, and retention factor. An acidic pH was selected in order to positively charge the analyzed peptides, the pI's of which are about 3 in water buffer solutions. A good selectivity and resolution was achieved at pH <2.8; at higher pH the three parameters decreased due to reduced or even zero charge of peptides. The increase in the ionic strength of the buffer present in the mobile phase caused a decrease in retention factor for all the studied compounds due to the decreased interaction between analytes and stationary phase. Raising the ACN concentration in the mobile phase in the range 40–80% v/v caused an increase in both retention factor, retention time, and resolution due to the hydrophilic interactions of IOPs with free silanols and sulfonic groups of the stationary phase.
Viscous dissipative fluid flow past a semi‐infinite vertical plate with variable surface temperature
Authors: Palani G. 
Published: May 2007

AbstractAn analysis of the effect of viscous dissipative heat on two‐dimensional viscous incompressible fluid flow past a semi‐infinite vertical plate with variable surface temperature is carried out. The dimensionless governing equations are unsteady, two‐dimensional, coupled, and non‐linear governing equations. A most accurate, unconditionally stable and fast converging implicit finite‐difference scheme is used to solve the non‐dimensional governing equations. Velocity and temperature of the flow have been presented graphically for various parameters occurring in the problem. The local and average skin friction and Nusselt number are also shown graphically. It is observed that greater viscous dissipative heat causes a rise in the temperature. Copyright © 2007 John Wiley & Sons, Ltd.
Unawareness of motor impairment and emotions in right hemispheric stroke: a preliminary investigation
Authors: Spalletta Gianfranco , Serra Laura , Fadda Lucia , Ripa Alessandra , Bria Pietro , Caltagirone Carlo 
Published: May 2007

AbstractBackgroundAwareness may lack in some stroke patients who are not capable of evaluating the nature and severity of illness. Thus, unawareness may have different forms such as anosognosia, neglect, and alexithymia or unawareness of emotions. In this study we investigated the relationship among anosognosia, neglect, alexithymia, and cognition.MethodsFifty consecutive right stroke inpatients were approached within the first 3 months from the acute event. Anosognosia was measured with the Bisiach scale, alexithymia with the TAS‐20 scale and neglect with line crossing, letter cancellation, figure and shape copying, and line bisection tests. A neuropsychological test battery was used to measure different areas of cognition.Resultsdespite the strong comorbidity rate among the different forms of unawareness, there are patients who suffer from pure forms of these types of lack of awareness. A multivariate logistic regression model evidenced that presence of neglect (OR = 10.3; 95% CI = 1.4–76.3; p = 0.023) and more difficulty in describing feelings (TAS‐20 F2 subscore; OR = 1.3; 95% CI = 1.1–1.7; p = 0.014) were the only predictors of anosognosia. In addition, anosognosics with alexithymia performed worst in a frontal task such as the verbal fluency task (p = 0.042) and in the verbal span forward task (p = 0.026) than pure anosognosics.ConclusionsAnosognosia for motor impairment is strictly associated with a specific form of unawareness of emotions. Future studies have to clarify if frontal cognitive impairment previously described in anosognosics is a manifestation of unawareness of emotions or anosognosia for motor impairment. Copyright © 2007 John Wiley & Sons, Ltd.
Construction of a combinatorial library of 2‐(4‐oxo‐4H‐1‐benzopyran‐3‐yl)‐4‐thiazolidinones by microwave‐assisted one‐pot parallel syntheses
Authors: Zhou Zhong‐Zheng , Huang Wei , Ji Feng‐Qin , Ding Ming‐Wu , Yang Guang‐Fu 
Published: May 2007

AbstractA one‐pot liquid‐phase combinatorial synthesis of 2‐(4‐oxo‐4H‐1‐benzopyran‐3‐yl)‐4‐thiazolidinones bearing diverse substituents at the 3‐position under microwave irradiation was successfully performed using 3‐formyl chromone, primary amine, and mercaptoacetic acid as reactants. Compared to an identical library generated by conventional parallel synthesis, the microwave‐assisted parallel synthesis approach dramatically decreased the reaction time from an average of 9 h to 5 min, and substantially increased the product yields. The coupling of microwave technology with liquid‐phase combinatorial synthesis constitutes a novel and particularly attractive avenue for the rapid generation of structurally diverse libraries. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:381–389, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20309
Synthesis and antimicrobial activity of new functionalized derivatives of [1,2,4]triazolo[4,3‐a]pyrimidin‐5(1H)‐one
Authors: Shawali Ahmad S. , Mahran Asma M. , Nada Afaf A. 
Published: May 2007

AbstractNew functionalized 1,7‐diaryl‐6‐cyano‐1,2,4‐triazolo[4,3‐a]pyrimidin‐5(1H)‐one derivatives (5a–j) were synthesized via reaction of 5‐cyano‐6‐phenyl‐2‐thiouracil1with the respective hydrazonoyl halides2a–jand their biological activity was evaluated. The mechanism and the regioselectivity of the studied reactions are discussed. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:393–398, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20311
Reactions with dimethylformamide‐dimethylacetal: Synthesis and reactions of several new pyridine and pyrazolo[3,4‐b]pyridine derivatives
Authors: Elneairy Mohamed A. A. , Gad‐Elkareem Mohamed A. M. , Taha Adel M. 
Published: May 2007

Abstract6‐Aminopyridine‐2(1H)‐thiones 1a,b reacted with dimethylformamide‐dimethylacetal (DMF‐DMA) to give the corresponding 6‐{[(N,N‐dimethylamino)methylene]amino}pyridine derivatives 2a,b. The latter compounds reacted with hydrazine hydrate to afford the 3,6‐diamino‐1H‐pyrazolo[3,4‐b]pyridine derivative 4 and 3‐amino‐5‐hydrazino‐1H‐pyrazolo[4′,3′:5,6]pyrido[2,3‐d]pyrimidine derivative 7, respectively. Compound 4 condensed with DMF‐DMA to yield the 3,6‐bis{[(N,N‐dimethylamino)methylene]amino}‐1H‐pyrazolo[3,4‐b]pyridine derivative 10, which reacted with malononitrile to give the corresponding pyridopyrazolopyrimidine derivative 15. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:399–404, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20312
Modification of styrene polymer with organosilicon groups
Authors: Assadi M. G. , Mahkam M. , Tajrezaiy Z. 
Published: May 2007

AbstractThe homopolymer of 4‐chloromethylstyrene (P1) and its copolymers with styrene (in various mole ratios) were synthesized by bulk and solution free radical polymerizations, respectively, at 70 ± 1°C using α,α′‐azobis(isobutyronitrile) as an initiator. Lithiation of these soluble polymers in THF at −78°C was done and reacted with electrophiles such as tert‐BuMe2Si, Et3Si, and Me3SiCH2 in the presence of 4,4′‐di‐tert‐butylbiphenyl (DTBB) as a catalyst to produce modified polystyrene. In the other way, trimethylsilylmethyl lithium substitute as a nucleophile was covalently linked to the homopolymer and copolymer. The polymers were characterized by IR, 1H NMR, 13C NMR, differential scanning calorimetry (DSC), and gel permeation chromatography. DSC showed that incorporation of silyl substitute in the side chains of homopolymer and copolymers increases the rigidity of the polymers and, subsequently, their glass transition temperature. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:414–420, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20314
Original recyclization of S‐phenacyl derivatives of 4‐acylamino‐2‐mercapto‐1,3‐oxazoles and their analogues
Authors: Balia Andrei G. , Belyuga Aleksandr G. , Brovarets Vladimir S. , Vasylenko Aleksandr N. , Turov Aleksandr V. , Gakh Andrei A. , Drach Boris S. 
Published: May 2007

AbstractReadily accessible acylamino(chloro)acetophenones, if treated with sodium rhodanide and α‐halogenocarbonyl compounds, provide 4‐acylamino‐5‐aryl‐2‐mercapto‐1,3‐oxazole derivatives which undergo recyclization on heating in polyphosphoric acid to give substituted 1,3‐thiazol‐2(3H)‐ones or 1,3‐thiazolidin‐2,4‐diones containing 2‐alkyl(aryl)‐5‐aryl‐1,3‐oxazol‐4‐yl residues at the N3 atom. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:432–437, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20317
Synthesis of phenoxy‐substituted spiro‐ansa phosphazene derivatives
Authors: Begeç Saliha 
Published: May 2007

AbstractIn this study, reactions of 2,4,4,6,6‐pentachloro‐2‐(2,4,6‐trimethylphenoxy)cyclo‐2λ5,4λ5,6λ5‐triphosphazatriene (1) and 2,4,4,6,6‐pentachloro‐2‐(2,4,6‐tritertbutylphenoxy)cyclo‐2λ5,4λ5,6λ5‐triphosphazatriene (2) with 2,2′‐dihydroxybiphenyl (3) in acetone in the presence of potassium carbonate have been investigated. Mono ansa (4) and spiro‐ansa (5) derivatives were obtained from of 3 with 1, while mono spiro (6) and mono ansa (7) derivatives were obtained from 2. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:372–375, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20322
Human neutrophil elastase and collagenase sequestration with phosphorylated cotton wound dressings
Authors: Edwards J. Vincent , Howley Phyllis S. 
Published: May 2007

AbstractThe design and preparation of wound dressings that redress the protease imbalance in chronic wounds is an important goal of wound healing and medical materials science. Chronic wounds contain high levels of tissue and cytokine‐destroying proteases including matrix metalloprotease and neutrophil elastase. Thus, the lowering of excessive protease levels in the wound environment by wound dressing sequestration prevents the breakdown of extracellular matrix proteins and growth factors necessary for wound healing. Phosphorylated cotton wound dressings were prepared to target sequestration of proteases from chronic wound exudate through a cationic uptake binding mechanism involving salt bridge formation of the positively charged amino acid side chains of proteases with the phosphate counterions of the wound dressing fiber. Dressings were prepared by applying sodium hexametaphosphate and diammonium phosphate in separate formulations to cotton gauze by pad/dry/cure methods. Phosphorylated cotton dressings were assessed for their ability to lower elastase and collagenase activity. The phosphorylated cotton dressings lowered elastase and collagenase activity 40–80% more effectively than the untreated cotton wound dressings under conditions that mimic chronic wound exudate. Efficacy of the phosphorylated cotton was found to be related to the level of phosphorylation and a lower pH due to protonated phosphate at the surface of the dressing. The capacity of the modified gauze to sequester continued elastase secretions similar to that found in a chronic wound over a 24‐h period was retained within a 80% retention of elastase sequestration and was dose‐dependent. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res 2007
A fracture‐mechanics‐based approach to fracture control in biomedical devices manufactured from superelastic Nitinol tube
Authors: Robertson S. W. , Ritchie R. O. 
Published: May 2007

AbstractSeveral key fracture‐mechanics parameters associated with the onset of subcritical and critical cracking, specifically the fracture toughness, crack‐resistance curve, and fatigue threshold, have recently been reported for the superelastic alloy Nitinol, in the product form of the thin‐walled tube that is used to manufacture several biomedical devices, most notably endovascular stents. In this study, we use these critical parameters to construct simple decision criteria for assessing the quantitative effect of crack‐like defects in such Nitinol devices with respect to their resistance to failure by deformation or fracture. The criteria are based on the (equivalent) crack‐initiation fracture toughness and fatigue threshold stress‐intensity range, together with the general yield strength and fatigue endurance strength, and are used to construct a basis for design against single‐event (overload) failures as well as for time‐/cycle‐delayed failures associated with fatigue. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008
Interaction of cells and nanofiber scaffolds in tissue engineering
Authors: Venugopal J. , Low Sharon , Choon Aw Tar , Ramakrishna S. 
Published: May 2007

AbstractNanofibers and nanomaterials are potentially recent additions to materials in relation to tissue engineering (TE). TE is the regeneration of biological tissues through the use of cells, with the aid of supporting structures and biomolecules. Mimicking architecture of extracellular matrix is one of the challenges for TE. Biodegradable biopolymer nanofibers with controlled surface and internal molecular structures can be electrospun into mats with specific fiber arrangement and structural integrity for drug delivery and TE applications. The polymeric materials are widely accepted because of their ease of processability and amenability to provide a large variety of cost‐effective materials, which help to enhance the comfort and quality of life in modern biomedical and industrial society. Today, nanotechnology and nanoscience approaches to scaffold design and functionalization are beginning to expand the market for drug delivery and TE is forming the basis for highly profitable niche within the industry. This review describes recent advances for fabrication of nanofiber scaffolds and interaction of cells in TE. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 2008