bluuebunny/crossref_metadata_2025 huggingface dataset:
Successive aggression: another pattern of polyadic aggressive interactions in a captive group of japanese macaques
Authors: Rizaldi  , Watanabe Kunio
Published: October 2007

Several patterns of polyadic aggressive interactions have been previously reported. Here, we describe another pattern of polyadic interactions in a captive group of Japanese macaques (Macaca fuscata fuscata) that we designate as “successive aggression”. We defined successive aggression as aggression by the original actor toward a second recipient within a very short time interval after the initial aggression toward the first recipient. We compared the patterns and characteristics of successive aggression to those of redirection. Among 2,698 recorded aggressive interactions, 80 involved successive aggressions and 75 were classified as redirections. Females, especially adult females, performed and received more successive aggression, whereas males, especially adult males, performed and received more redirection. Successive aggression often occurred when the first recipient exhibited counter‐aggression. Successive aggression was then directed toward an individual related to the first recipient, such as the mother, offspring or sibling. The targets of redirection were not relatives of the first aggressor in most cases, but were clearly subordinate individuals. The dominance relationships among the aggressor, the first recipient and the second recipients were usually non‐linear for successive aggression, but were linear for most cases of redirection. These results suggest that monkeys can anticipate possible opponents who may intervene in ongoing aggressive interactions and suppress them, even though they are not yet hostile toward these individuals. Successive aggression may function to establish and maintain dominance relationships among matrilineal groups through repeated confirmations. Am. J. Primatol. 70:349–355, 2008. © 2007 Wiley‐Liss, Inc.
Effects of cyclic compression and thermal aging on dynamic properties of neoprene rubber bearings
Authors: Chou Hsoung‐Wei , Huang Jong‐Shin
Published: October 2007

The dynamic properties of rubber bearings frequently used as isolators in structures could be significantly deteriorated because of the change of microstructure in rubber caused by cyclic compression and thermal aging. As a result, a catastrophic failure of bridges and buildings unexpectedly occurs when they are subjected to earthquake attack. Here, the dynamic properties of neoprene rubber bearings before and after different cycles of compressive loading or various periods of thermal aging were first measured and compared to each other. On the basis of the experimental results, the effects of cyclic compression and thermal aging on the stiffness, energy absorption, and equivalent viscous damping coefficient of neoprene rubber bearings are investigated. It is found that the deterioration of dynamic properties of neoprene rubber bearings caused by either cyclic compression or by thermal aging is significant and should be taken into account in designing rubber bearings. © 2007 Wiley Periodicals, Inc. JAppl Polym Sci, 2008
Lewis acid–base property of P(VDF‐co‐HFP) measured by inverse gas chromatography
Authors: Shi Baoli , He Mingjia
Published: October 2007

Poly (vinylidene fluoride‐co‐hexafluoropropylene) P(VDF‐co‐HFP) is an excellent material for polymer electrolytes of lithium ion battery. To enhance the lithium ion transference number, some metal oxides were often embedded into P(VDF‐co‐HFP). The promising mechanism for the increase in lithium ionic conductivity was Lewis acid‐base theory. In this experiment, the Lewis acid–base properties of P(VDF‐co‐HFP) were measured by inverse gas chromatography (IGC). The Lewis acid constant Ka of P(VDF‐co‐HFP) is 0.254, and the base constant Kb is 1.199. Compared with other polymers characterized by IGC, P(VDF‐co‐HFP) is the strongest Lewis basic polymers. Except aluminum ion, lithium ion is the strongest Lewis acidic ion according to their η value of Lewis acids. Therefore, a strong Lewis acid–base interaction will exist between lithium ion and P(VDF‐co‐HFP). This will restrict the transference of lithium ion in P(VDF‐co‐HFP). To enhance the lithium ion transference by blending other metal ions into P(VDF‐co‐HFP), it is suggested that the preferential ions should be Al3+, Mg2+, Na+, and Ca2+ because these metal ions have relative large η values. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Invasive Cells in the Placentome of Andean Populations of Mabuya: An Endotheliochorial Contribution to the Placenta?
Authors: Vieira Simón , de Perez Gloria , Ramírez‐Pinilla Martha Patricia
Published: October 2007

New world lizards of the genus Mabuya have the most specialized level of placentotrophy among reptiles known to date, and related to that, they have the most complex allantoplacenta characterized by a series of morphological specializations that converge with those known for eutherian mammals. One of these specializations is the placentome that is found in the embryonic pole of the incubation chamber. In the mature allantoplacenta, this structure is morphologically the most complex, which could support an important amount of nutrient exchange between mother and fetus. According to the relationship between the chorioallantois and the syncytial uterine epithelia, the placenta of Mabuya populations shows some interesting similarities to the synepitheliochorial type. Recently, cells of chorionic origin have been found invading the syncytial uterine epithelium, and in very close proximity with uterine blood vessels. In this study, we describe the relationship between these invasive chorionic cells, the uterine syncytium, and the subjacent blood vessels of several populations of this genus, by means of high resolution optical microscopy and transmission electron microscopy. Cell groups originating from the chorion, of variable size and shape, penetrate the uterine syncytial epithelium extending complex cytoplasmic projections that come in contact with uterine capillaries and form an extensive and complex double‐membrane system that surrounds the capillary. The close relationship between the chorion and the maternal circulation suggests that the Mabuya placentome shows some characteristics of an endotheliochorial placenta. This finding constitutes so far the only documented example of an endotheliochorial placentation in Reptilia. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.
Expression of the Serotonin Transporter (SERT) in the Choroid Plexuses from Buffalo Brain
Authors: Pavone Luigi M. , Tafuri Simona , Mastellone Vincenzo , Morte Rossella Della , Lombardi Pietro , Avallone Luigi , Maharajan Veeramani , Staiano Norma , Scala Gaetano
Published: October 2007

Choroid plexuses (CPs) play pivotal roles in a wide range of processes that establish, survey, and maintain the biochemical and cellular status of the central nervous system. Mammalian CPs contain a very high density of serotonin receptors, and serotonin has been shown to affect CP functions. The serotonin transporter (SERT) regulates the entire serotonergic system, including serotonin receptors by means of modulation of serotonin concentration in the extracellular fluid. In this study, the expression of SERT in the CPs from the brain of a mammalian species, Bubalis bubalis, was established. By immunogold labeling in scanning electron microscopy, SERT immunoreactivity was found to be localized on the apical surface of the choroid epithelium. In particular, SERT positivity was detected on the apical portion of villi, and both on the membrane and in the cytoplasm of grouped cells on the surface of the choroid epithelium. Significantly, no SERT was detected in blood vessels irrigating the CPs. The expression of SERT mRNA transcripts of 440 bp in the CPs was detected by reverse‐transcription polymerase chain reaction, and Western blotting analysis revealed the presence of three isoforms of the protein with molecular masses of approximately 70, 80, and 140 kDa, respectively, probably corresponding to differently glycosylated SERT. Our findings provide the first report of SERT detection in the CPs of buffalo brain and indicate that this protein is locally synthesized from the choroid epithelial cells. We suggest that SERT might have an important role in mammalian CPs, possibly regulating the serotonin flow between brain and rest of the body. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.
Aquaporin 9 (AQP9) Localization in the Adult Dog Testis Excurrent Ducts by Immunohistochemistry
Authors: Domeniconi Raquel Fantin , Orsi Antonio Marcos , Justulin Luis Antonio , Beu Célia Cristina Leme , Felisbino Sérgio Luis
Published: October 2007

Aquaporins (AQPs) are small, intrinsic membrane proteins that are present in many cell types involved in fluid transport. AQP9 is a major apical water channel that is expressed throughout the efferent ducts, epididymis, and vas deferens, as well as in other regions of the human and rodent male reproductive tract. The target of this study was to examine the expression of AQP9 in epithelial cells in the adult dog efferent ducts, epididymis, and vas deferens. Samples of dog male reproductive tract comprising fragments of the testis; initial segment, caput, corpus, and cauda of the epididymis; and vas deferens were obtained from eight adult mongrel dogs. Immunohistochemistry and Western blotting procedures were used to show AQP9 localization and distribution. AQP9 expression was not detected either in dog seminiferous tubules or rete testis. However, apical labeling for AQP9 was detected in the different regions of epididymis and vas deferens, with the reaction being less intense in the caput epididymis. Thus, AQP9 is abundantly expressed in dog male reproductive tract, in which it is an important apical pathway for transmembrane flow of water and neutral solutes. Anat Rec, 2007. © 2007 Wiley‐Liss, Inc.
Effective temperature vs. line‐depth ratio for ELODIE spectra: Gravity and rotational velocity effects
Authors: Biazzo K. , Frasca A. , Catalano S. , Marilli E.
Published: October 2007

The dependence on the temperature of photospheric line‐depth ratios (LDRs) in the spectral range 6190–6280 Å is investigated by using a sample of 174 ELODIE Archive stellar spectra of luminosity class from V to III. The rotational broadening effect on LDRs is also studied. We provide useful calibrations of effective temperature versus LDRs for giant and main sequence stars with 3800 ≃ Teff ≃6000 K and v sin i in the range 0–30 km s–1. We found that, with the exception of very few line pairs, LDRs, measured at a spectral resolution as high as 42 000, depend on v sin i and that, by neglecting the rotational broadening effect, the Teff determination can be wrong by ∼100 K in the worst cases. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Effects of Porphyrin Substituents on Film Structure and Photoelectrochemical Properties of Porphyrin/Fullerene Composite Clusters Electrophoretically Deposited on Nanostructured SnO2 Electrodes
Authors: Imahori Hiroshi , Ueda Masahiro , Kang Soonchul , Hayashi Hironobu , Hayashi Shinya , Kaji Hironori , Seki Shu , Saeki Akinori , Tagawa Seiichi , Umeyama Tomokazu , Matano Yoshihiro , Yoshida Kaname , Isoda Seiji , Shiro Motoo , Tkachenko Nikolai V. , Lemmetyinen Helge
Published: October 2007

We have systematically examined the substituent effects of meso‐tetraphenylporphyrins on film structures and the photoelectrochemical properties of the composite clusters of free‐base porphyrin and C60 electrophoretically deposited on nanostructured SnO2 electrodes. The photocurrent generation efficiency was found to correlate with the complexation ability of the porphyrin for C60. Basically, the incident photon‐to‐current efficiency (IPCE) value was increased with increasing relative amounts of the porphyrin versus C60 in the films. The unique molecular arrangement of the porphyrin with the simple, specific substituents (i.e., methoxy groups at the meta‐positions of the meso‐phenyl rings of tetraphenylporphyrins (3,5‐OMeTPP; TPP=tetraphenylporphyrin)) and C60 on SnO2 electrodes resulted in the largest IPCE value (ca. 60 %) among this type of photoelectrochemical device. The rapid formation of the composite clusters and microcrystals from the combination of 3,5‐OMeTPP and C60 in a mixed solvent is unique as the association is accelerated by intermolecular interactions (i.e., hydrogen‐bonding and CH–π interactions) between the methoxy groups of the porphyrins and the porphyrin/C60, in addition to the π–π interactions between the porphyrins/C60 and C60 molecules. Both the films and single crystals composed of the porphyrin and C60 exhibited remarkably high electron mobility (7×10−2 and 0.4 cm2 V−1 s−1), which is comparable to the value for highly efficient bulk heterojunction solar cells. Our experimental results have successfully demonstrated the importance of nanostructured electron‐ and hole‐transporting pathways in bulk heterojunction solar cells. Such a finding will provide basic and valuable information on the design of molecular photovoltaics at the molecular level.
Stereochemical Consequences of Threefold Symmetry in Asymmetric Catalysis: Distorting C3 Chiral 1,1,1‐Tris(oxazolinyl)ethanes (“Trisox”) in CuII Lewis Acid Catalysts
Authors: Foltz Carole , Stecker Björn , Marconi Guido , Bellemin‐Laponnaz Stéphane , Wadepohl Hubert , Gade Lutz H.
Published: October 2007

The underlying conceptual differences in exploiting two‐ and threefold rotational symmetry in the design of chiral ligands for asymmetric catalysis have been addressed in a comparative study of the catalytic performance of bisoxazoline (BOX) and tris(oxazolinyl)ethanes (trisox) containing copper(II) Lewis acid catalysts. The differences become apparent in constructing new catalysts by systematically “deforming” the stereodirecting ligand by inverting chiral centres or replacing chiral by achiral oxazolines. The catalytic α‐amination of ethyl 2‐methylacetoacetate with dibenzyl azodicaboxylate, which occurs with high enantioselectivity for both Ph2‐BOX and Ph3‐trisox copper catalysts, has been employed as the test reaction. In the trisox–copper complex [CuII(iPr3‐trisox)(κ2‐O,O′‐MeCOCHCOOEt)]+[BF4]− (1), which was characterised by X‐ray diffraction, two of the oxazoline groups are coordinated to the central copper atom, whilst the third oxazoline unit is dangling with the N‐donor pointing away from the metal centre. A similar arrangement is found for the stereochemically “mixed” C1‐trisox complex [CuII{(Ph3‐trisox(R,S,S)}(κ2‐O,O′‐MeCOCHCOOEt)(H2O)]+[ClO4]− (2), in which the phenyl substituents adopt a first coordination sphere meso arrangement. The almost identical selectivity of the Ph3‐trisox(R,R,R)‐ and Ph2‐BOX(R,R)‐derived catalysts is as expected from the proposed model of the active catalyst based on a partially decoordinated podand. The behaviour of the “desymmetrised” trisox–Cu catalysts may be rationalised in terms of a general steady‐state kinetic model for the three possible active bisoxazoline–copper species, which are expected to be in rapid exchange with each other in solution. This applies to both the trisox derivatives with stereochemically inverted and achiral oxazoline rings. The study underscores previous observations of superior performance of the catalysts bearing C3‐chiral stereodirecting ligands as compared to systems of lower symmetry.
Convenient Syntheses and Transformations of 2‐C‐Malonyl Carbohydrates
Authors: Yin Jian , Sommermann Thomas , Linker Torsten
Published: October 2007

2‐C‐malonyl carbohydrates were synthesized in only few steps and high yields by radical additions of malonates to glycals. For the first time, the undesired formation of nitrates was completely suppressed with anhydrous cerium ammonium nitrate (CAN) as oxidizing agent. A coherent explanation for the high stereoselectivities of the additions togluco‐configured glycals was provided by variation of the substituents in the 3‐position. We established steric effects for the face selectivity, and electronic effects strongly influence the reactivity of the double bonds. The scope and limitation of transition‐metal‐mediated radical reactions in the synthesis of 2‐C‐branched carbohydrates was thoroughly investigated. Thus, unsaturated disaccharides and benzyl‐protected glycals were used as substrates for the first time. Finally, the 2‐C‐malonyl carbohydrates were transformed into various products by decarboxylation, saponification and reduction, which afforded interesting precursors forC‐disaccharides. In this paper we describe the syntheses of more than 40 new 2‐C‐analogues of carbohydrates, which were isolated in high yields in analytically pure form. Therefore, the transition‐metal‐mediated radical addition of malonates to glycals offers a simple and convenient entry to such important carbohydrate derivatives.
On the Conjugation Length for Oligo(ethynylnaphthalene)‐Based Molecular Rods
Authors: Benniston Andrew C. , Harriman Anthony , Rewinska Dorota B. , Yang Songjie , Zhi Yong‐Gang
Published: October 2007

The synthesis is described for a small series of oligomers built from (2, 3, 4 or 6) ethynyl‐naphthalene repeat units and end‐capped with solubilising 1,2,3‐tris‐dodecyloxy‐benzene groups. These compounds absorb in the near‐UV region and exhibit strong fluorescence in both fluid solution and a glassy matrix at 77 K. The spectral profiles are fully consistent with a structurally heterogeneous ground state becoming more planar upon excitation and with the low‐temperature glass further stabilising the co‐planar orientation. The absorption and fluorescence maxima move towards lower energy with increasing number of repeat units and there is a corresponding increase in the Huang–Rhys factor for the radiative process. The non‐radiative rate constants also depend on molecular length and are well explained in terms of the energy‐gap law. In contrast, very weak phosphorescence is observed at 77 K for which the peak maximum and lifetime remain insensitive to the number of naphthalene units. The triplet lifetimes recorded at ambient temperature are also independent of the molecular length but the triplet–triplet absorption spectra change throughout the series. These results are discussed in terms of the degree of electronic coupling between adjacent repeat units for each of the relevant excited states. During these studies it was noted that the rate of intersystem crossing to the triplet manifold is but weakly affected by heavy‐atom perturbers. A non‐fluorescent complex is formed between iodoethane and the molecular rod but the corresponding bimolecular process occurs at well below the diffusion‐controlled limit. This behaviour is considered in terms of spin‐orbit coupling between the excited states and takes account of the differing conjugation lengths.
Functionalised Hybrid Materials of Conducting Polymers with Individual Fibres of Cellulose
Authors: Kelly Fern M. , Johnston James H. , Borrmann Thomas , Richardson Michael J.
Published: October 2007

Polypyrrole and polyaniline conducting polymer composites with individual fibres of cellulose have been successfully prepared and characterised. For this, individual Kraft paper pulp fibres have been fully encapsulated with polypyrrole and polyaniline by direct polymerisation of the respective monomers using ferric chloride and ammonium persulfate as the oxidants. These novel conducting polymer/cellulose fibre composite materials exhibit the inherent properties of both components. They include the electrical and chemical properties of polypyrrole and polyaniline and the strength, flexibility and available surface areas of the cellulose fibre. This allows for interesting opportunities for the development of new added‐value products in the paper and packaging industries. Additionally, by utilising the redox active surface of the fibre's polymer coating, silver ions have been reduced to silver metal, thereby producing cellulose/conducting polymer/silver composites. Silver and its compounds have long been identified for their bactericidal effects and thus antimicrobial properties are imparted to the hybrid materials. This gives rise to applications requiring the inhibition of microbial growth. The chemical and physical characterisation of such products has been carried out using scanning electron microscopy (SEM), cyclic voltammetry, X‐ray photoelectron spectroscopy (XPS) energy dispersive spectroscopy (EDS) and electrical conductivity measurements, and additionally the testing of their antimicrobial activity. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Nucleosides with 5′‐Fixed Lipid Groups – Synthesis and Anchoring in Lipid Membranes
Authors: Brodersen Nicolai , Li Jun , Kaczmarek Oliver , Bunge Andreas , Löser Ludwig , Huster Daniel , Herrmann Andreas , Liebscher Jürgen
Published: October 2007

Nucleosides were synthesized bearing one or two lipophilic groups at the 5′‐position. The lipophilic substituents can be fixed at a 5′‐amino group or at the 5′‐phosphate moiety. Selected examples of these lipophilic nucleosides are shown by solid‐state NMR spectroscopy to anchor in lipid double layers. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Novel 4‐Aminoquinolines through Microwave‐Assisted SNAr Reactions: a Practical Route to Antimalarial Agents
Authors: Melato Sergio , Coghi Paolo , Basilico Nicoletta , Prosperi Davide , Monti Diego
Published: October 2007

4‐Aminoquinolines have recently been indicated to be an important class of chemotherapeutic agents for artemisinin‐based antimalarial combination therapy. A rapid, cheap, possibly clean and scalable route to 4‐aminoquinolines endowed with multiple diversity is therefore badly needed. Classically, they have been prepared by means of SNAr reactions, requiring hazardous or costly reagents and conditions and complex purification procedures. In this paper, microwave flash‐heating chemistry is shown to allow the efficient conversion of the available 4,7‐dichloroquinoline into a library of aminoquinolines in high yields and purities, with no need for further purification steps and requiring very short reaction times. Some of the compounds in this library were active against chloroquine‐sensitive and chloroquine‐resistant parasite strains.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Palladium‐Catalyzed Intramolecular C–O Bond Formation: An Approach to the Synthesis of Chiral Benzodioxocines
Authors: Neogi Arpita , Majhi Tirtha P. , Achari Basudeb , Chattopadhyay Partha
Published: October 2007

Palladium‐catalyzed intramolecular aryl etherification using bulky binaphthylphosphane or bis(diphenylphosphanyl)ferrocene ligands is shown to be a convenient method for the synthesis of eight‐membered oxygen heterocycles. Application of this methodology to a sugar derivative led to the synthesis of chiral benzodioxocine. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Effects of mimicking: acting prosocially by being emotionally moved
Authors: Stel Mariëlle , van Baaren Rick B. , Vonk Roos
Published: October 2007

Mimicry is functional for empathy and bonding purposes. Studies on the consequences of mimicry at a behavioral level demonstrated that mimicry increases prosocial behavior. However, these previous studies focused on the mimickee. In the present paper, we investigated whether mimickers also become more helpful due to mimicry. In two studies, we have demonstrated that participants, who mimicked expressions of a person shown on a video, donated more money to a charity than participants who did not mimic. Moreover, the processes by which mimicry and prosocial behavior are related largely remain empirically unexamined in existing literature. The results of Study 2 confirmed our hypothesis that affective empathy mediates the relationship between mimicry and prosocial behavior. This suggests that mimicry created an affective empathic mindset, which activated prosocial behaviors directed toward others. Copyright © 2007 John Wiley & Sons, Ltd.
Signal Processing in Normal Pulse Voltammetry by Means of Dedicated Mother Wavelet
Authors: Jakubowska Małgorzata , Kubiak Władysław W.
Published: October 2007

In the work, a new signal processing algorithm is presented and applied for the transformation of the sigmoidal shaped curves, registered in normal pulse voltammetry (NPV), to the peak shaped curves. The method is based on the continuous wavelet transform (CWT) and specially constructed mother wavelet defined using the ideal wave‐shaped curve. Transformation of the signal, elimination of noises and separation of overlapping data can be achieved in one step by means of proposed procedure. The operation and effectiveness of the algorithm is presented using ideal, noised and overlapping simulated curves. The process of simultaneous determination of lead and indium as well as transformation of curves registered for elements' ions: lead, indium, thallium and cadmium is described. The obtained results show substantial improvement of the performance of NPV.
Voltammetric Determination of Xanthine with a Single‐Walled Carbon Nanotube‐Ionic Liquid Paste Modified Glassy Carbon Electrode
Authors: Xiao Fei , Ruan Changping , Li Jiangwen , Liu Lihong , Zhao Faqiong , Zeng Baizhao
Published: October 2007

Single‐walled carbon nanotube (SWNT) and room temperature ionic liquid (i.e., 1‐butyl‐3‐methylimidazolium hexaflourophosphate, BMIMPF6) were used to fabricate paste modified glassy electrode (GCE). It was found that the electrode showed sensitive voltammetric response to xanthine (Xt). The detection limit was 2.0×10−9 M and the linear range was 5.0×10−9 to 5.0×10−6 M. The electrode also displayed good selectivity and repeatability. In the presence of uric acid (UA) and hypoxanthine (Hx) the response of Xt kept almost unchanged. Thus this electrode could find application in the determination of Xt in some real samples. The analytical performance of the BMIMPF6‐SWNT/GCE was demonstrated for the determination of Xt in human serum and urine samples.
Determination of Mercury by Anodic Stripping Voltammetry with a Gold Nanoparticle‐Modified Glassy Carbon Electrode
Authors: Abollino Ornella , Giacomino Agnese , Malandrino Mery , Piscionieri Giuseppina , Mentasti Edoardo
Published: October 2007

The aim of this work is the development of a procedure for the determination of aqueous Hg(II) by anodic stripping voltammetry at a gold nanoparticle‐modified glassy carbon electrode (AuNPs‐GCE). The signal of aqueous Hg(II) was measured in the square wave mode; the effect of potential scan parameters, deposition potential and deposition time on the analytical signal was examined. The supporting electrolyte was 0.06 M HCl. The repeatability, the linearity, the accuracy, the detection limit of the procedure and the interferences of other cations and of anions were evaluated. The performance of the AuNPs‐GCE was compared with those of a solid (SGE) and a film (FGE) gold electrode: the AuNPs‐GCE showed to provide lower detection limits and higher repeatability. The renewable surface permits to eliminate memory effects, to maintain a stable baseline and response, and to avoid frequent mechanical cleaning steps. The applicability of the AuNPs‐GCE for Hg(II) determination in drinking waters, sediments and pharmaceuticals was demonstrated.
Analysis of tetracycline residues in bovine milk by CE‐MS with field‐amplified sample stacking
Authors: Wang Shufang , Yang Ping , Cheng Yiyu
Published: October 2007

A rapid, sensitive, and robust CE‐MS method has been developed for the determination of tetracycline, oxytetracycline, and chlortetracycline in milk. Field‐amplified sample stacking with electromigration injection (FASS‐EMI) was used for the online concentration of tetracyclines. The conditions of separation, MS detection, and stacking were systematically optimized. The optimum buffer composition was 35 mM Tris, 1.1% formic acid, 5% methanol, and 15% ACN. By using the online concentration method of field‐enhanced sample stacking (FESI)‐EMI stacking, the sensitivity was increased six‐ to seven‐fold. The RSDs (n = 6) of the relative migration time of tetracyclines were 1.1–1.4% for intraday and 2.4–2.9% for interday. The RSDs (n = 6) of the relative peak area of tetracyclines were 3.2–4.6% for intraday and 4.7–6.1% for interday. The LODs (S/N = 3) were 7.14 ng/mL for tetracycline, 11.4 ng/mL for oxytetracycline, and 14.9 ng/mL for chlortetracycline. The method has been successfully used to analyze tetracyclines residues in bovine milk.
Optimization of the SNR‐resolution tradeoff for registration of magnetic resonance images
Authors: Kale Shoan C. , Lerch Jason P. , Henkelman R. Mark , Chen X. Josette
Published: October 2007

Image registration serves many applications in medical imaging, including longitudinal studies, treatment verification, and more recently, morphometry. Registration processing is regularly applied in magnetic resonance (MR) images, where imaging is highly adaptable in capturing soft tissue contrast. To obtain the greatest registration accuracy in MR imaging, the inherent imaging tradeoff between SNR and resolution at a given scan time should be optimized for computational accuracy, rather than human viewing. We investigated this SNR‐resolution tradeoff to optimize registration for digital morphometry. Tradeoff images were simulated from acquired gold standard MR images to emulate a shorter, constant acquisition time, but at the expense of SNR, resolution, or both. The group of images from each tradeoff was nonlinearly registered toward an average atlas producing deformation fields, useful for identifying differences in morphology. The gold standard data were also registered. The deformation fields were used to evaluate registration performance of each tradeoff relative to the gold standard. For fixed scan times, the optimal SNR for registration with MR imaging was found to be ∼20. Image resolution should be adjusted to produce this target voxel SNR when registration is a central processing task. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Glycan modification of the tumor antigen gp100 targets DC‐SIGN to enhance dendritic cell induced antigen presentation to T cells
Authors: Aarnoudse Corlien A. , Bax Marieke , Sánchez‐Hernández Marta , García‐Vallejo Juan J. , van Kooyk Yvette
Published: October 2007

Dendritic cells (DC) have gained much interest in the field of anticancer vaccine development because of their central function in immune regulation. However, the clinical application of ex vivo cultured DC has significant disadvantages. A vaccine that targets dendritic cells in vivo and enhances antigen presentation would be of great benefit. Because of its DC‐restricted expression pattern, and its function as an antigen uptake receptor, DC‐SIGN is an interesting candidate target structure for human immature DC. Here, we studied whether modification of the melanoma differentiation antigen gp100 with DC‐SIGN‐interacting glycans enhances targeting to human DC. A high‐mannose form of gp100, as protein or as tumor lysate, not only interacted specifically with DC through DC‐SIGN but also resulted in an enhanced antigen presentation to gp100‐specific CD4+ T cells. Our results indicate that glycan modification of tumor antigens to target C‐type lectin receptors, such as DC‐SIGN, is a new way to develop in vivo targeting DC strategies that simultaneously enhance the induction of tumor‐specific T cells. © 2007 Wiley‐Liss, Inc.
Effect of age, birth cohort and period of death on skin melanoma mortality in Spain, 1975 through 2004
Authors: Cayuela Aurelio , Rodríguez‐Domínguez Susana , Vigil Eduardo , Conejo‐Mir Julián Sánchez
Published: October 2007

Recent statistics cohort analysis of mortality reveals that skin melanoma rates are dropping in the younger cohorts. Therefore, the aim of this study is to provide up‐to‐date information and to analyze recent changes in skin melanoma mortality trends in Spain during the period of 1975–2004 using joinpoint regression and age–period–cohort models. Between 1975 and 2004, the age‐standardized (overall) mortality rates for skin melanoma increased from 0.3 to 1.3 per 100,000 person‐years for males and from 0.2 to 0.8 per 100,000 person‐years for females, with an estimated annual percentage of change of 4.8 and 4.3%, respectively. In men and women, the best fit was found for the full model, which simultaneously considered the effects of age, period and cohort. The risks among both males and females increased in each successive birth cohort born between 1895 and 1950. Thereafter, the risks declined through the most recent birth cohort born in 1970. Examination of the mortality trends by age group and birth cohort revealed that the recent less rapidly rising (men) or stabilizing (women) age‐adjusted skin melanoma mortality rates in Spain were a result of declining mortality in the younger age groups and more recent birth cohorts. The particularly favorable trends in young people suggest that a further decline in mortality from skin melanoma in Spain is likely to occur within the next few years. © 2007 Wiley‐Liss, Inc.
Flutamide reduced prostate cancer development and prostate stem cell antigen mRNA expression in high grade prostatic intraepithelial neoplasia
Authors: Zhigang Zhao , Wenlu Shen
Published: October 2007

High‐grade prostatic intraepithelial neoplasia (HGPIN) appears to represent an ideal target for chemoprevention of prostate cancer (PCa). HGPIN responds to androgen ablation and has prostate stem cell antigen (PSCA) mRNA expression. One hundred and seventy two patients with isolated HGPIN were randomized in a double‐blind manner to receive flutamide 250 mg/day (86 cases) or a placebo (86 cases) for 12 months and were rebiopsied at 12 and 60 months. PSCA mRNA expression was assessed in the prestudy and 12‐month biopsies by in situ hybridization. The incidence of subsequent PCa was 11.6% in the flutamide group when compared with 30.2% in the placebo group over a follow‐up period of 5 years (p = 0.0027). PSCA mRNA expression levels were significantly declined after treatment compared with that before treatment (p < 0.001). After treatment, 66 patients had reduced PSCA mRNA expression, in whom none was found with cancer on follow‐up, however, 13 cases had increased PSCA mRNA expression levels, in whom 11 were found with cancer. Cox regression analysis demonstrated that HGPIN with increased PSCA mRNA expression after flutamide had an increased relative risk of 4.33 to develop subsequent cancer (95% confidence intervals: 2.48–7.36; p < 0.001). Seventeen (19.8%) cases had the flutamide‐associated side effects, which were graded as mild, but all did not discontinue study. Flutamide can effectively and safely reduce PCa development and significantly suppress PSCA mRNA expression in men with isolated HGPIN, whereas the increased PSCA mRNA expression after therapy may be a clinically adverse predictor for cancer onset. © 2007 Wiley‐Liss, Inc.
The association between oral contraceptive use and lobular and ductal breast cancer in young women
Authors: Nyante Sarah J. , Gammon Marilie D. , Malone Kathleen E. , Daling Janet R. , Brinton Louise A.
Published: October 2007

Recent reports indicate that the incidence of lobular breast cancer is increasing at a faster rate than ductal breast cancer, which may be due to the differential effects of exogenous hormones by histology. To address this issue, we examined whether the relationship between oral contraceptive use and incident breast cancer differs between lobular and ductal subtypes in young women. A population‐based sample of in situ and invasive breast cancer cases between ages 20 and 44 were recruited from Atlanta, GA; Seattle‐Puget Sound, WA and central New Jersey. Controls were sampled from the same areas by random‐digit dialing, and were frequency matched to the expected case age distribution. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated using polytomous logistic regression. Among the 100 lobular cancers, 1,164 ductal cancers, and 1,501 controls, the odds ratios for oral contraceptive ever use were 1.10 (95% CI = 0.68–1.78) for lobular cancers and 1.21 (95% CI = 1.01–1.45) for ductal cancers, adjusted for study site, age at diagnosis, and pap screening history. Our results suggest that the magnitude of the association between ever use of oral contraceptives and breast cancer in young women does not vary strongly by histologic subtype. These results are similar to previous studies that report little difference in the effect of oral contraceptive use on breast cancer by histology. © 2007 Wiley‐Liss, Inc.
Development of mature cartilage constructs using novel three‐dimensional porous scaffolds for enhanced repair of osteochondral defects
Authors: Kasahara Yasuhiko , Iwasaki Norimasa , Yamane Shintaro , Igarashi Tatsuya , Majima Tokifumi , Nonaka Sachiko , Harada Kazuo , Nishimura Shin‐Ichiro , Minami Akio
Published: October 2007

In this study, we successfully developed two types of volume‐reduced three‐dimensional scaffolds, including cushion‐ and cylinder‐shape scaffolds, fabricated from chitosan‐based hyaluronic acid hybrid polymer fibers. Using these scaffolds combined with a bioreactor system, we regenerated histologically and mechanically mature cartilage constructs. The final goal of this study was to clarify the ability of this engineered cartilage construct to induce cartilage repair in osteochondral defects. The mature cartilage constructs regenerated with two types of scaffolds were implanted into 5‐mm diameter osteochondral defects in the patellar groove of rabbits. At 12 weeks after implantation, the reparative tissues consisted of hyaline‐like cartilage with evidence of stable fusion to adjacent native cartilage and normal reconstitution of subchondral bone. The histological score of these tissues significantly outranked the value of untreated tissue. Biomechanically, compression modulus of reparative tissue at 12 weeks postoperatively was comparative to that of normal articular cartilage. Our results indicate that the implantation of constructs with mature cartilage have potential as a better approach for joint resurfacing. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Effects of pH and fluoride concentration on the corrosion of titanium
Authors: Lindholm‐Sethson B. , Ardlin B.I.
Published: October 2007

The aim of this investigation was to confirm and summarize the corrosion behavior of titanium in saline solution at different pH and fluoride concentration, and to characterize the surface films and the stability of a passive and aged titanium surface using open circuit potential measurements, electrochemical impedance spectroscopy, and anodic polarization curves. The results from the electrochemical measurements were related to titanium released after 2‐min brushing with saline solutions with different pH and fluoride concentration, that is, simulating tooth brushing with fluoride containing prophylactic substances. Titanium was analyzed using atomic adsorption spectrophotometry. The pH in the saline solution was varied between 4 and 7 with additions of sodium fluoride up to 1.0 wt %. The presence of fluoride in solution was unfavorable for the stability of titanium and led to corrosion and the release of titanium especially at low pH. The combination of low pH and presence of fluoride ions in solution destroyed a passive film on the titanium surface even after aging for 170 h in neutral saline solution. The results do not necessarily imply the occurrence of biological soft tissue related effects even if a physical contact between titanium and the surrounding milieu is prevalent. To provide a general understanding of electrochemical techniques in biomaterial research, much effort was put in the qualitative description of the results, with the intention to provide a broader understanding of especially the impedance method to other researchers. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2008
Extruded collagen‐polyethylene glycol fibers for tissue engineering applications
Authors: Zeugolis D. I. , Paul R. G. , Attenburrow G.
Published: October 2007

The repair of anterior cruciate ligament, skin, tendon and cartilage remains a challenging clinical problem. Extruded collagen fibers comprise a promising scaffold for tissue engineering applications; however the engineering of these fibers has still to be improved to bring this material to clinical practice. Herein we investigate the influence of collagen concentration, the amount of PEG Mw 8K and the extrusion tube internal diameter on the properties of these fibers. Ultrastructural evaluation revealed packed intra‐fibrillar structure. The thermal properties were found to be independent of the collagen concentration, the amount of PEG or the extrusion tube internal diameter (p > 0.05). An inversely proportional relationship between dry fiber diameter and stress at break was found. The 20% PEG was identified as the optimal amount required for the production of reproducible fibers. Increasing the collagen concentration resulted in fibers with higher diameter (p < 0.001), force (p < 0.001) and strain at break (p < 0.02) values, whilst the stress at break (p < 0.001) and the modulus (p < 0.007) values were decreased. Increasing the extrusion tube internal diameter influence significantly (p < 0.001) all the investigated mechanical properties. Overall, extruded collagen fibers were produced with properties similar to those of native or synthetic fibers to suit a wide range of tissue engineering applications. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Activated platelets positively regulate RANKL‐mediated osteoclast differentiation
Authors: Weicht Barbara , Maitz Philipp , Kandler Barbara , Fischer Michael B. , Watzek Georg , Gruber Reinhard
Published: October 2007

Platelets induce osteoclastogenesis in total bone marrow cultures where hematopoietic cells can interact with stromal cells. Whether or not activated platelets directly act on hematopoietic cells to promote their differentiation into osteoclasts remains unknown. Here we report that platelet releasates (PRS) increase osteoclastogenesis in stroma‐depleted, macrophage colony‐stimulating factor (M‐CSF)‐dependent bone marrow cells when cultured in the presence of receptor activator of NF‐kappaB ligand (RANKL). The increased number of tartrate‐resistant acid phosphatase‐positive multinucleated cells (MNC) was paralleled by an enhanced transcription of osteoclast specific genes. Osteoclastogenesis was observed with hematopoietic cells previously depleted of B‐cells or T‐cells. Immunoprecipitation of transforming growth factor‐beta (TGF‐β) decreased the osteoclastogenic capacity of the PRS. PRS enhanced phosphorylation of Smad‐2, a downstream signaling mediator of TGF‐β. PRS increased phosphorylation of p38 and c‐Jun NH(2)‐terminal kinase (JNK), whereas only blocking of p38 but not JNK signaling suppressed osteoclastogenesis. These results suggest that activated platelets can enhance osteoclastogenesis by providing a source of TGF‐β and by activating osteoclastogenic signaling pathways. J. Cell. Biochem. 102: 1300–1307, 2007. © 2007 Wiley‐Liss, Inc.
Biomarkers, regerons, and pathways to lethal cancer
Authors: Qiao Meng , Pardee Arthur B.
Published: October 2007

Cancer is a disease of “outlaw” cells that become mutated in regulatory mechanisms. They have lost normal self controls and relationships to the whole organism. Cancers can progress by several pathways from a normal cell to malignant cancer, from bad to worse. Questions about advisability of treatment for some cancers arise from the possibility that they are arrested during progression and so never become lethal. Techniques could be developed to determine the degree of progression and possibility for successful treatment. This article is intended to suggest a way of looking at cancer. It is not a review so references to research articles are infrequent. J. Cell. Biochem. 102: 1076–1086, 2007. © 2007 Wiley‐Liss, Inc.
Unstructured mathematical model for biomass, lactic acid and bacteriocin production by lactic acid bacteria in batch fermentation
Authors: Vázquez José Antonio , Murado Miguel Anxo
Published: October 2007

BACKGROUND: A simple macroscopical model was proposed to describe the fermentation kinetics of growth, bacteriocins and lactic acid production by Lactococcus lactis and Pediococcus acidilactici in a batch system. The equations used were: the logistic reparametrized for growth, the Luedeking–Piret model for bacteriocin production, the maintenance energy model for glucose consumption; and the homofermentative balance equation for lactic acid formation.

RESULTS: In all the cultures, the mathematical models, consistents and robusts, adjusted, perfectly, the experimental kinetic profiles. Also, the corresponding kinetic parameters were significant, so much biological as statistically.

CONCLUSIONS: The group of integrated equations used, besides showing high accuracy in predicting the studied bioproductions, established a useful tool for the control of lactic acid bacteria kinetics in bioreactors in terms of its statistical consistency. Copyright © 2007 Society of Chemical Industry
On k‐detour subgraphs of hypercubes
Authors: Arizumi Nana , Hamburger Peter , Kostochka Alexandr
Published: October 2007

A spanning subgraph G of a graph H is a k‐detour subgraph of H if for each pair of vertices $x,y \in V(H)$, the distance, ${\rm dist}_G(x,y)$, between x and y in G exceeds that in H by at most k. Such subgraphs sometimes also are called additive spanners. In this article, we study k‐detour subgraphs of the n‐dimensional cube, $Q^n$, with few edges or with moderate maximum degree. Let $\Delta(k,n)$ denote the minimum possible maximum degree of a k‐detour subgraph of $Q^n$. The main result is that for every $k\geq 2$ and $n \geq 21$

On the other hand, for each fixed even $k \geq 4$ and large n, there exists a k‐detour subgraph of $Q^n$ with average degree at most $2 + 2^{4-k/2}+o(1)$. © 2007 Wiley Periodicals, Inc. J Graph Theory 57: 55–64, 2008
On the dispersion of a non‐orthogonal TLM cell
Authors: Li Zaiqing , Le Maguer Sandrick , Ney Michel
Published: October 2007

The numerical dispersion of a non‐orthogonal transmission line matrix (TLM) algorithm is for the first time investigated. First of all, the dispersion relation is derived in the most general possible case. Then, the validation is carried out in the analysis of a simple one‐dimensional example. Results show that the theory is in excellent agreement with the numerical simulation. Numerical results concerning various cell shape dispersion characteristics are presented and show some relatively weak numerical dispersion even for rather highly distorted cells. Finally, some indications concerning cell shape selection to minimize the non‐orthogonal TLM cell are proposed. Copyright © 2007 John Wiley & Sons, Ltd.
Influence of the k‐space trajectory on the dynamic T1‐weighted signal in quantitative first‐pass cardiac perfusion MRI at 3T
Authors: Kim Daniel
Published: October 2007

The dynamic T1‐weighted signal in first‐pass myocardial perfusion MRI can vary as a function of k‐space trajectory. The purpose of this study, therefore, was to compare the relative T1‐weighted signal produced by the linear, centric, and reverse centric k‐space trajectories at 3T. The centric k‐space trajectory yielded higher arterial input function (AIF) than the linear and reverse centric k‐space trajectories (6.21 ± 0.84 vs. 4.75 ± 0.75 vs. 4.39 ± 0.85 mM, respectively; N = 9; P < 0.01), and the reverse centric k‐space trajectory yielded higher myocardial signal contrast (as a fraction of equilibrium magnetization) than the linear and centric k‐space trajectories (0.17 ± 0.02 vs. 0.12 ± 0.02 vs. 0.05 ± 0.01, respectively; N = 9; P < 0.001). Compared to the linear k‐space trajectory, the centric k‐space trajectory is relatively optimal for the quantification of AIF, whereas the reverse centric k‐space trajectory is relatively optimal for high contrast of myocardial wall enhancement. Magn Reson Med, 2007. © 2007 Wiley‐Liss, Inc.