bluuebunny/crossref_metadata_2025 huggingface dataset:
A novel direct aerodynamically assisted threading methodology for generating biologically viable microthreads encapsulating living primary cells
Authors: Arumuganathar Sumathy , Irvine Scott , McEwan Jean R. , Jayasinghe Suwan N.
Published: October 2007

In a recent discovery, coaxial electrospinning was explored to encapsulate living organisms within a continuous bio‐polymeric microthread from which active biological scaffolds were fabricated (Townsend‐Nicholson and Jayasinghe, Biomacromolecules 2006, 7, 3364). The cells were demonstrated to have gone through all expected cellular activity without their viability being compromised. These biologically active threads and scaffolds have direct and tremendous applicability from regenerative to therapeutic medicine. Currently these post‐processed cells as composite threads and scaffolds are being investigated in‐depth at a cellular level to establish if the processing methodology has any affect on the cellular make‐up. We now demonstrate a competing non‐electric field driven approach for fabricating composite threads and scaffolds influenced only by a differential pressure. We refer to this novel composite thread to scaffold fabrication methodology as coaxial aerodynamically assisted bio‐threading (CAABT). Our investigations firstly, demonstrate that this technique can process handle living organisms without biologically perturbing them in anyway. Secondly the process is elucidated as possessing the ability to form composite active threads from which biologically viable scaffolds are formed. Finally our study employs florescent activated cell sorting (FACScan), a method by which the cellular dynamics and viability are quantified on control and threaded cellular samples at two prescribed time points. In parallel with FACScan, optical comparison of cellular morphology at three time points within a period of three weeks is carried out to photographically observe any changes in the post‐processed cellular phenotype. Our developmental investigations into this novel aerodynamically assisted threading methodology has unearthed a unique biomicrofabrication approach, which joins cell electrospinning in the cell threading to scaffold fabrication endeavor. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Establishing the optimal sizes of different kinds of biorefineries
Authors: Wright Mark , Brown Robert C.
Published: October 2007

This paper explores the factors that influence the optimal size of biorefineries and the resulting unit cost of biofuels produced by them. Technologies examined include dry grind corn to ethanol, lignocellulosic ethanol via enzymatic hydrolysis, gasification and upgrading to hydrogen, methanol, and Fischer Tropsch liquids, gasification of lignocellulosic biomass to mixed alcohols, and fast pyrolysis of lignocellulosic biomass to bio‐oil. On the basis of gallons of gasoline equivalent (gge) capacity, optimally sized gasification‐to‐biofuels plants were found to be 50–100% larger than biochemical cellulosic ethanol plants. Biorefineries converting lignocellulosic biomass into transportation fuels were found to be optimally sized in the range of 240–486 million gge per year compared to 79 million gge per year for a grain ethanol plant. Among the biofuel options, ethanol, whether produced biochemically or thermochemically, is the most expensive to produce. Lignocellulosic biorefineries will require 4.7–7.8 million tons of biomass annually compared to 1.2 million tons of corn grain for a grain ethanol plant. Factors that could reduce the optimal size of lignocellulosic biorefineries are discussed. © 2007 Society of Chemical Industry and John Wiley & Sons, Ltd
Modeling Disease Incidence Data with Spatial and Spatio Temporal Dirichlet Process Mixtures
Authors: Kottas Athanasios , Duan Jason A. , Gelfand Alan E.
Published: October 2007

Disease incidence or mortality data are typically available as rates or counts for specified regions, collected over time. We propose Bayesian nonparametric spatial modeling approaches to analyze such data. We develop a hierarchical specification using spatial random effects modeled with a Dirichlet process prior. The Dirichlet process is centered around a multivariate normal distribution. This latter distribution arises from a log‐Gaussian process model that provides a latent incidence rate surface, followed by block averaging to the areal units determined by the regions in the study. With regard to the resulting posterior predictive inference, the modeling approach is shown to be equivalent to an approach based on block averaging of a spatial Dirichlet process to obtain a prior probability model for the finite dimensional distribution of the spatial random effects. We introduce a dynamic formulation for the spatial random effects to extend the model to spatio‐temporal settings. Posterior inference is implemented through Gibbs sampling. We illustrate the methodology with simulated data as well as with a data set on lung cancer incidences for all 88 counties in the state of Ohio over an observation period of 21 years. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Long‐distance corticocortical GABAergic neurons in the adult monkey white and gray matter
Authors: Tomioka Ryohei , Rockland Kathleen S.
Published: October 2007

A subgroup of GABAergic neurons has been reported to project over long distances in several species. Here we demonstrate that long‐distance cortically projecting nonpyramidal neurons occur in monkeys in both white and gray matter. Nonpyramidal neurons were first identified morphologically. Visualization of Golgi‐like details was achieved by retrograde infection from injections of an adenovirus vector, producing enhanced green fluorescent protein (EGFP) under control of a neuron‐specific promoter. Injections in areas V1, V4, TEO, and posterior TE resulted in EGFP‐expressing nonpyramidal neurons up to 1.5 cm distant from the injections, mainly in the white matter. Some neurons occurred in the gray matter, mainly in layer 3, but also in layers 5 and 6, and, very occasionally, layer 1. As control, we injected cholera toxin subunit B, a standard retrograde tracer, in V4, and observed a similarly wide distribution of neurons in the white matter. Second, the GABAergic identity of EGFP‐expressing nonpyramidal neurons was established by colabeling for EGFP and GAD67 in selected tissue sections. Most neurons positive for EGFP and GAD67 were positive for somatostatin (SS; 90%). Of those neurons positive for EGFP and SS, almost all were also positive for neuronal nitric oxide synthase or m2 muscarinic receptor, but only 23% were also positive for calretinin. None were positive for parvalbumin. We conclude that long‐distance projecting GABAergic neurons 1) are phylogenetically conserved, although in monkeys most gray matter neurons are in the upper layers, and 2) are heterogeneous in terms of their neurochemistry, location, and potentially function. J. Comp. Neurol. 505:526–538, 2007. © 2007 Wiley‐Liss, Inc.
Cellular and subcellular localization of the GABAB receptor 1a/b subunit in the rat periaqueductal gray matter
Authors: Barbaresi Paolo
Published: October 2007

The inhibitory effects of γ‐aminobutyric acid (GABA)ergic neurotransmission in the periaqueductal gray matter (PAG) are mediated, at least partly, by metabotropic GABAB receptor subtypes whose cellular and subcellular localization is still unknown. We performed immunohistochemical experiments with an antibody against GABAB receptor subtype 1a/b (GABABR1a/b) by using light and electron microscopy. On light microscopy, GABABR1a/b immunoreactivity (IR) was in all columns, defined by cytochrome oxidase histochemistry. Neuropil labeling was strongest in the lateral portion of dorsolateral PAG. Labeled neurons, albeit not numerous, were in ventrolateral, dorsal, and medial subdivisions and were sparser in dorsolateral PAG. Labeling was mostly on the soma of PAG neurons. Sometimes GABABR1a/b IR spread along proximal dendrites; in these cases bipolar neurons were the most common type. On electron microscopy, GABABR1a/b IR was mainly on dendrites (54.92% of labeled elements) and axon terminals (21.90%) making synapses with labeled and unlabeled postsynaptic elements. Presynaptic labeling was also on unmyelinated and myelinated axons (overall 8% of all labeled elements). Postsynaptically, GABABR1a/b IR was at extrasynaptic sites on dendritic shafts; spines were always unlabeled. On axon terminals, GABABR1a/b IR was on extrasynaptic membranes and sometimes on presynaptic membrane specializations. Of the labeled elements, 13.03% elements were distal astrocytic processes (dAsPs) surrounding both symmetric and asymmetric synapses whose pre‐ and postsynaptic elements were often labeled. Immunoreactive dAsPs were around the soma and dendrites of both labeled and unlabeled neurons. These findings provide insights into the intrinsic PAG organization and suggest that presynaptic, postsynaptic, and glial GABAB receptors may play crucial roles in controlling PAG neuronal activity. J. Comp. Neurol. 505:478–492, 2007. © 2007 Wiley‐Liss, Inc.
Type III adenylyl cyclase localizes to primary cilia throughout the adult mouse brain
Authors: Bishop Georgia A. , Berbari Nicolas F. , Lewis Jacqueline , Mykytyn Kirk
Published: October 2007

Solitary primary cilia project from nearly every cell type in the human body. These organelles are considered to have important sensory and signaling functions. Although primary cilia have been detected throughout the mammalian brain, their functions are unknown. The study of primary cilia in the brain is constrained by the scarcity of specific markers for these organelles. We previously demonstrated that type III adenylyl cyclase (ACIII) is a marker for primary cilia on neonatal hippocampal neurons in vivo and in vitro. We further showed that ACIII localizes to cilia on cultured glial cells. Here, we report that ACIII is a marker for primary cilia throughout many regions of the adult mouse brain. Furthermore, we report that ACIII localizes to primary cilia on choroid plexus cells and some astrocytes in the brain, which to our knowledge is the first report of a marker for visualizing cilia on glia in vivo. Overall, our data indicate that ACIII is a prominent marker of primary cilia in the brain and will provide an important tool to facilitate further investigations into the functions of these organelles. J. Comp. Neurol. 505:562–571, 2007. © 2007 Wiley‐Liss, Inc.
Morphology and ontogeny of rat perirhinal cortical neurons
Authors: Furtak Sharon Christine , Moyer James Russell , Brown Thomas Huntington
Published: October 2007

Golgi‐impregnated neurons from rat perirhinal cortex (PR) were classified into one of 15 distinct morphological categories (N = 6,891). The frequency of neurons in each cell class was determined as a function of the layer of PR and the age of the animal, which ranged from postnatal day 0 (P0) to young adulthood (P45). The developmental appearance of Golgi‐impregnated neurons conformed to the expected “inside‐out” pattern of development, meaning that cells populated in deep before superficial layers of PR. The relative frequencies of different cell types changed during the first 2 weeks of postnatal development. The largest cells, which were pyramidal and spiny multipolar neurons, appeared earliest. Aspiny stellate neurons were the last to appear. The total number of Golgi‐impregnated neurons peaked at P10–12, corresponding to the time of eye‐opening. This early increase in the number of impregnated neurons parallels observations in other cortical areas. The relative frequency of the 15 cell types remained constant between P14 to P45. The proportion of pyramidal neurons in PR (≈50%) was much smaller than is typical of neocortex (≈70%). A correspondingly larger proportion of PR neurons were nonpyramidal cells that are less common in neocortex. The relative frequency distribution of cell types creates an overall impression of considerable morphological diversity, which is arguably related to the particular manner in which this periallocortical brain region processes and stores information. J. Comp. Neurol. 505:493–510, 2007. © 2007 Wiley‐Liss, Inc.
Water‐Soluble Phenanthroline Complexes of Rhodium, Iridium and Ruthenium for the Regeneration of NADH in the Enzymatic Reduction of Ketones (Eur. J. Inorg. Chem. 30/2007)
Authors: Canivet Jérôme , Süss‐Fink Georg , Štěpnička Petr
Published: October 2007

The cover picture shows an example of combined organometallic and enzymatic catalysis in aqueous solution. The rhodium complex [(C5Me5)Rh(phenanthroline)Cl]+ continuously regenerates NADH from NAD+ by using formate as hydrogen source, and the enzyme alcohol dehydrogenase from Rhodococcus erythropolis enantioselectively reduces the ketone to the corresponding alcohol by means of the NADH formed. This work illustrates the increasing interest in enantioselective catalysis with the environmentally friendly water as solvent. Details are discussed in the article by G. Süss‐Fink et al. on p. 4736 f.
Influence of the Double‐Bond Geometry of the Michael Acceptor on Copper‐Catalyzed Asymmetric Conjugate Addition
Authors: Vuagnoux‐d'Augustin Magali , Alexakis Alexandre
Published: October 2007

Focusing on mechanistic aspects, a study of the influence of the (E)/(Z) double‐bond geometry of the Michael acceptor on the enantioselectivity of copper‐catalyzed asymmetric conjugate addition reactions has been realized. In spite of numerous articles concerning copper‐catalyzed asymmetric conjugate addition reactions, the major factors of such a reaction are quite difficult to elucidate. Although our experiments have not allowed us to define strict rules, they have highlighted some factors not to be neglected when considering the approach of the copper reagent to the double bond, such as (E)/(Z) isomerization and steric aspects, which could change the reactive conformation of the substrate. Electronic effects could also modify the polarization of the double bond and influence the nucleophilic attack. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Versatile One‐Pot Synthesis of 3‐Alkenylcoumarins
Authors: Königs Pia , Neumann Olivia , Hackelöer Kristina , Kataeva Olga , Waldvogel Siegfried R.
Published: October 2007

A variety of 2‐acyl‐, 2‐aroyl‐ and 2‐formyl‐substituted phenols are converted in a one‐pot reaction with α,β‐unsaturated carboxylic acid chlorides into the corresponding 3‐alkenylcoumarins. Especially the labile 3‐vinylcoumarins are readily available by the simple to perform protocol. If longer alkenyl chains are involved in position 3, small molecules with excellent organo gelating properties are established. The mode of action for such aggregates is confirmed by X‐ray analysis of an analogue.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Organocatalytic Asymmetric β‐Hydroxylation of α,β‐Unsaturated Ketones
Authors: Carlone Armando , Bartoli Giuseppe , Bosco Marcella , Pesciaioli Fabio , Ricci Paolo , Sambri Letizia , Melchiorre Paolo
Published: October 2007

The highly enantioselective organocatalytic β‐hydroxylation of α,β‐unsaturated ketones was accomplished by using oximes as the oxygen‐centered nucleophile. Optically active products are obtained with enantioselectivity up to 94 %. Central to these studies was the use of catalytic primary amine salt A, in which both the cation and the anion are chiral. Amine A exhibits high reactivity and selectivity for iminium‐ion catalysis with enones. The potential interest of this novel transformation was demonstrated with the easy conversion of the Michael adducts in enantioenriched anti and syn 1,2‐diols without erosion of the optical purity.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Selective visuo‐haptic processing of shape and texture
Authors: Stilla Randall , Sathian K.
Published: October 2007

Previous functional neuroimaging studies have described shape‐selectivity for haptic stimuli in many cerebral cortical regions, of which some are also visually shape‐selective. However, the literature is equivocal on the existence of haptic or visuo‐haptic texture‐selectivity. We report here on a human functional magnetic resonance imaging (fMRI) study in which shape and texture perception were contrasted using haptic stimuli presented to the right hand, and visual stimuli presented centrally. Bilateral selectivity for shape, with overlap between modalities, was found in a dorsal set of parietal areas: the postcentral sulcus and anterior, posterior and ventral parts of the intraparietal sulcus (IPS); as well as ventrally in the lateral occipital complex. The magnitude of visually‐ and haptically‐evoked activity was significantly correlated across subjects in the left posterior IPS and right lateral occipital complex, suggesting that these areas specifically house representations of object shape. Haptic shape‐selectivity was also found in the left postcentral gyrus, the left lingual gyrus, and a number of frontal cortical sites. Haptic texture‐selectivity was found in ventral somatosensory areas: the parietal operculum and posterior insula bilaterally, as well as in the right medial occipital cortex, overlapping with a medial occipital cortical region, which was texture‐selective for visual stimuli. The present report corroborates and elaborates previous suggestions of specialized visuo‐haptic processing of texture and shape. Hum Brain Mapp 2008. © 2007 Wiley‐Liss, Inc.
Role of αvβ6 integrin in acute biliary fibrosis
Authors: Wang Bruce , Dolinski Brian M. , Kikuchi Noriko , Leone Diane R. , Peters Marion G. , Weinreb Paul H. , Violette Shelia M. , Bissell Montgomery D.
Published: October 2007

Acute biliary obstruction leads to periductal myofibroblasts and fibrosis, the origin of which is uncertain. Our study provides new information on this question in mice and humans. We show that bile duct obstruction induces a striking increase in cholangiocyte αvβ6 integrin and that expression of this integrin is directly linked to fibrogenesis through activation of transforming growth factor beta (TGF-β). Administration of blocking antibody to αvβ6 significantly reduces the extent of acute fibrosis after bile duct ligation. Moreover, in β6-null mice subjected to the injury, fibrosis is reduced by 50% relative to that seen in wild-type mice, whereas inflammation occurs to the same extent. The data indicate that αvβ6, rather than inflammation, is linked to fibrogenesis. It is known that αvβ6 binds latent TGF-β and that binding results in release of active TGFβ. Consistent with this, intracellular signaling from the TGFβ receptor is increased after bile duct ligation in wild-type mice but not in β6−/− mice, and a competitive inhibitor of the TGFβ receptor type II blocks fibrosis to the same extent as antibody to αvβ6. In a survey of human liver disease, expression of αvβ6 is increased in acute, but not chronic, biliary injury and is localized to cholangiocyte-like cells.

Conclusion :

Cholangiocytes respond to acute bile duct obstruction with markedly increased expression of αvβ6 integrin, which is closely linked to periductal fibrogenesis. The findings provide a rationale for the use of inhibitors of αvβ6 integrin or TGFβ for down-regulating fibrosis in the setting of acute or ongoing biliary injury.
Hepatocyte growth factor signaling pathway inhibits cholesterol 7α-hydroxylase and bile acid synthesis in human hepatocytes
Authors: Song Kwang-Hoon , Ellis Ewa , Strom Stephen , Y.L. Chiang John
Published: October 2007

Bile acid synthesis in the liver is regulated by the rate-limiting enzyme cholesterol 7α-hydroxylase (CYP7A1). Transcription of the

CYP7A1

gene is inhibited by bile acids and cytokines. The rate of bile acid synthesis is reduced immediately after partial hepatectomy and during the early stage of liver regeneration. Hepatocyte growth factor (HGF) released from stellate cells activates a receptor tyrosine kinase c-Met, in hepatocytes and stimulates signaling pathways that regulate cell growth, proliferation, and apoptosis. This study demonstrated that HGF strongly and rapidly repressed

CYP7A1

mRNA expression and the rate of bile acid synthesis in primary human hepatocytes. HGF rapidly induced c-Jun and small heterodimer partner mRNA and protein expression and increased phosphorylation of ERK1/2, JNK, and c-Jun. Specific inhibitors of protein kinase C, extracellular signal–regulated kinase 1/2 (ERK1/2), and c-Jun N-terminal kinase (JNK) blocked HGF inhibition of CYP7A1 expression. Knockdown of c-Met by small interfering RNA resulted in a significant increase in CYP7A1 and blocked HGF inhibition of

CYP7A1

mRNA expression. Chromatin immunoprecipitation assays showed that HGF induced recruitment of c-Jun and small heterodimer partner (SHP) but reduced recruitment of the coactivators peroxisome proliferators activated receptor ρ coactivator 1α (PGC-1α) and cAMP response element binding protein (CREB)–binding protein (CBP) to chromatin.

Conclusion:

This study demonstrated that HGF is a novel regulator of CYP7A1 and bile acid synthesis in human hepatocytes and may protect hepatocytes from accumulating toxic bile acids and developing intrahepatic cholestasis during the early stage of liver regeneration. (Hepatology 2007.)
Memory consolidation of landmarks in good navigators
Authors: Janzen Gabriele , Jansen Clemens , Turennout Miranda van
Published: October 2007

Landmarks play an important role in successful navigation. To successfully find your way around an environment, navigationally relevant information needs to be stored and become available at later moments in time. Evidence from functional magnetic resonance imaging (fMRI) studies shows that the human parahippocampal gyrus encodes the navigational relevance of landmarks. In the present event‐related fMRI experiment, we investigated memory consolidation of navigationally relevant landmarks in the medial temporal lobe after route learning. Sixteen right‐handed volunteers viewed two film sequences through a virtual museum with objects placed at locations relevant (decision points) or irrelevant (nondecision points) for navigation. To investigate consolidation effects, one film sequence was seen in the evening before scanning, the other one was seen the following morning, directly before scanning. Event‐related fMRI data were acquired during an object recognition task. Participants decided whether they had seen the objects in the previously shown films. After scanning, participants answered standardized questions about their navigational skills, and were divided into groups of good and bad navigators, based on their scores. An effect of memory consolidation was obtained in the hippocampus: Objects that were seen the evening before scanning (remote objects) elicited more activity than objects seen directly before scanning (recent objects). This increase in activity in bilateral hippocampus for remote objects was observed in good navigators only. In addition, a spatial‐specific effect of memory consolidation for navigationally relevant objects was observed in the parahippocampal gyrus. Remote decision point objects induced increased activity as compared with recent decision point objects, again in good navigators only. The results provide initial evidence for a connection between memory consolidation and navigational ability that can provide a basis for successful navigation. © 2007 Wiley‐Liss, Inc.
A single application of MK801 causes symptoms of acute psychosis, deficits in spatial memory, and impairment of synaptic plasticity in rats
Authors: Manahan‐Vaughan Denise , von Haebler Dorothea , Winter Christine , Juckel Georg , Heinemann Uwe
Published: October 2007

Schizophrenia is mostly a progressive psychiatric illness. Although cognitive changes in chronic schizophrenia have been investigated, little is known about the consequences of a single psychotic episode on memory mechanisms and formation. We investigated changes in hippocampal long‐term potentiation (LTP) and spatial memory in a rat model of an acute psychotic episode. Application of NMDA receptor antagonists, such as MK801 (dizolcilpine) in rats, have been shown to give rise to an acute and short‐lasting behavioral state, which mirrors many symptoms of schizophrenia. Furthermore, NMDA antagonist‐intake in humans elicits symptoms of schizophrenia such as hallucinations, delusions, and affective blunting. We therefore treated animals with a single systemic injection of MK801 (5 mg/kg). Increased stereotypy, locomotion, and ataxia were evident immediately after MK801‐treatment, with effects disappearing within 24 h. MK801‐treatment caused a disruption of prepulse inhibition of the acoustic startle reflex, 1 day but not 7 or 28 days after treatment. These effects were consistent with the occurrence of an acute psychotic episode. LTP was profoundly impaired in freely moving rats 7 days after MK801 application. Four weeks after treatment, a slight recovery of LTP was seen, however marked deficits in long‐term spatial memory were evident. These data suggest that treatment with MK801 to generate an acute psychotic episode in rats, gives rise to grave disturbances in synaptic plasticity and is associated with lasting impairments with the ability to form spatial memory. © 2007 Wiley‐Liss, Inc.
Chaetal arrangement provides no support for a close relationship of Sabellidae and Sabellariidae (Annelida)
Authors: Kieselbach Dominik , Hausen Harald
Published: October 2007

Sabellid and sabellariid polychaetes are regarded as sister groups in a number of recent phylogenetic analyses. This is based mainly on a shared specific arrangement of chaetae referred to as chaetal inversion. Remarkably, the uncini have a notopodial position in the abdomen, whereas capillary chaetae occur in the neuropodia in both taxa in contrast to the situation in putative relatives. However, in sabellids uncini and capillary chaetae change their position completely at the border between thorax and abdomen, whereas uncini are missing in the parathorax of Sabellariidae. Due to this difference the significance of the chaetal inversion for systematics has been subject to discussion for years. Serial semithin sections of parapodia of the Sabellidae Sabella pavonina, Branchiomma bombyx, Fabricia stellaris, and of the Sabellariidae Sabellaria alveolata were studied in order to obtain detailed information on their chaetal arrangement and sites of chaetal origin. SEM investigations and computer‐aided 3D‐reconstructions provide deep insight into the spatial organization of the rami. Though differing externally, the principal chaetal arrangement and the location of the formative sites turned out to be almost identical within the species of Sabellidae. Most chaetae are aligned in straight transverse rows with a dorsal site of origin within neuropodia and a ventral one in notopodia as is common in sedentary polychaetes. Semicircular and spiral arrangements are revealed to be modified transverse rows. Only in thoracic notopodia does an additional dorsocaudal formative site form distinct rows. The chaetal inversion in Sabellidae is additionally characterized by an abrupt change of capillary chaetae and uncini along with a sudden change of the parapodial morphology at the border between thorax and abdomen. All chaetae of S. alveolata are aligned in transverse rows with the same location of the formative sites as in sabellids and other sedentary polychaetes. However, in contrast to sabellids the chaetae are not inverted across a parathoracic abdominal border. Moreover, there is no inversion of the parapodial structure from parathorax to abdomen and the neuropodial chaetal composition changes gradually from parathorax to abdomen. The chaetal arrangement in Sabellariidae thus cannot be described as inverted along the body‐axis as in Sabellidae. Evolutionary steps implied by the assumption of an inverted chaetal pattern in a supposed common ancestor are discussed. It is concluded that the specific chaetal arrangement of Sabellidae and Sabellariidae arose independently and therefore provides no support for a sistergroup relationship of sabellids and sabellariids. J. Morphol., 2008. © 2007 Wiley‐Liss, Inc.
A Raman spectroscopic study of the Mapungubwe oblates: glass trade beads excavated at an Iron Age archaeological site in South Africa
Authors: Prinsloo Linda C. , Colomban Philippe
Published: October 2007

Oblate seed beads (2–4 mm) excavated on Mapungubwe hill, an Iron Age site in South Africa, were analysed with Raman microscopy and supportive techniques to determine the glass technology and pigments used to produce the beads. The Raman spectra and XRF analysis of the beads classify the glass as a typical soda/lime/potash glass similar to Islamic glass from the 8th century (Ommayad), but with higher levels of aluminium, iron and magnesium. The turquoise, bright green, bright yellow and orange colours were obtained by utilizing a combination of cassiterite (SnO2) and lead tin yellow type II (PbSn1−xSixO3). Doping with cobalt and manganese produced dark blue and plum‐coloured beads. The Fe‐S chromophore was detected through its resonance‐enhanced spectrum in the black beads. Corrosion of the black beads was investigated and an organic phase detected on the beads, which might have influenced the corrosion process. This detailed profile of the glass technology used to produce the Mapungubwe oblates might eventually help to determine their provenance. Copyright © 2007 John Wiley & Sons, Ltd.
Plasma electrolytic oxidation of AZ91D magnesium alloy with different additives and its corrosion behavior
Authors: Cao Fa‐he , Cao Jiang‐lin , Zhang Zhao , Zhang Jian‐qing , Cao Chu‐nan
Published: October 2007

Plasma electrolytic oxidation (PEO) of Mg‐based AZ91D alloys was investigated using 50 Hz AC anodizing technique in an alkaline borate solution, which contained a new kind of organic additive and without F, P, and Cr. The anodizing technological parameters have been optimized and a kind of ivory‐white smooth anodic film with high corrosion resistance was obtained. It was found that the formation of the anodic films was always coupled with sparking and oxygen evolution, whose intensity changed with the additive and anodizing voltage. All EIS plots have two capacitive loops and one low frequency inductive component. Two capacitive arcs present the barrier and porous layer of the PEO film and the inductive component in the low frequency domain is a complex behavior due to the porous structure connected to the electrolyte. EIS plots and fitting results show that a self‐sealing process of the PEO firm with different additives takes place in the beginning of immersion time, then corrosion attack becomes a preponderant process to promote the degradation of the film. Tafel results show that PEO treatment decreases the corrosion current density by four, even five orders of magnitude, while additives content does not affect strongly the electrochemical corrosion behavior. Salt spray test shows that the PEO film formed with NaAlO2 and Na2SiO3 presents good corrosion resistance, over 600 h without any sealing treatment. The difference of corrosion resistance arose by additives examined by electrochemical techniques and salt spray test does not show strict corresponding relationship.
Hydrogen permeation behavior and corrosion monitoring of steel in cyclic wet–dry atmospheric environment
Authors: Zheng C. , Huang Y. , Huo C. , Yu Q.
Published: October 2007

Hydrogen permeation of 16Mn steel under a cyclic wet–dry condition was investigated by Devanathan–Stachurski's electrolytic cell with a membrane covered on the exit side by a nickel layer and the weight loss was measured for each wet–dry cycle. The results show that hydrogen permeation current change with different atmospheric environment: distilled water, seawater, and seawater containing 100 ppm H2S. The results show that seawater can induce an increase in the hydrogen permeation current due to the hydrolyzation reaction. And after the increase, equilibrium is reached due to the equilibrium of hydrolyzation reaction effect and the block of the rust layer. On the other hand, H2S contamination also can induce an increase in the maximum hydrogen permeation current due to the hydrolyzation reaction. And H2S contamination delays the time that hydrogen permeation is detected because of the formation of the FeS(1−x) film. The FeS(1−x) film can block the absorption of hydrogen onto the specimen surface. The surface potential change and the pH change of the metal surface control the hydrogen permeation current. And a clear linear correlation exists between the quantities of hydrogen permeated through the 16Mn steel and the weight loss. Based on the linear correlation, we monitored the corrosion rate by monitoring the hydrogen permeation current by a sensor outside. Good coherences were shown between results in laboratory and outside.
The relation between electrochemical tests and in vitro evaluation of titanium alloy biocompatibility
Authors: Popa M. V. , Demetrescu I. , Iordachescu D. , Cimpean A. , Vasilescu E. , Drob P. , Vasilescu C. , Istratescu M.
Published: October 2007

In this paper, the electrochemical behaviour of the titanium and Ti‐6Al‐7Nb alloy in artificial saliva (Tani&Zucchi and Carter–Brugirard), ion release tests and in vitro biocompatibility of human osteoblasts (HOB) were studied. Titanium and its implant Ti‐6Al‐7Nb alloy present self‐passivation and very stable passive films in Tani&Zucchi artificial saliva of pH = 2.5; 5; 6.7; 9; the total quantity of ions released in the artificial saliva and corrosion rates are very low, proving a very good corrosion resistance and very low toxicity. In undoped and doped Carter–Brugirard saliva, the open circuit potentials have highly electropositive values, denoting passive state and good stability; the open circuit potential gradients, simulating the non‐uniformity of the saliva composition, show very low values, no danger for the implant integrity. The in vitro cytotoxicity of Ti‐6Al‐7Nb alloy was evaluated on the basis of cell morphology and cell viability. The results obtained revealed a high biocompatibility between HOB and Ti‐6Al‐7Nb alloy.
Chemical composition of new copper alloys for machining and its effect on their susceptibility to corrosion cracking
Authors: Eremiáš B. , Převorovský D. , Janík V. , Faltus J.
Published: October 2007

Zinc‐containing copper alloys, the so‐called α + β brasses, are commonly used in contact with potable water. These materials are alloyed with lead to improve machinability. In wrought special brass alloys, reducing the content of this alloying element or replacing it with alternative alloying additions may give rise to a new type of machinable copper alloys which differ from the original alloys by their contents of other modifier elements such as Si (or possibly, Mg, Bi, and P). These alloys have a very low content of lead required for the break‐up of chips during machining. Even though these types of brass exhibit a very good machinability, the effects of their chemical composition on the resistance of the alloy to corrosion cracking have not yet been given sufficient attention. This paper aims to present an assessment of three new types of machinable copper alloys regarding their susceptibility to stress corrosion cracking, in comparison to that of the lead‐alloyed variety, in 0.05 M NaCl, NaNO2, and Na2SO4 solutions. The slow strain rate test has been used for this purpose, and its results were correlated with metallographic evaluation of the number and depth of the cracks observed on the test specimen surfaces on completion of the test.
The effects of between‐partner congruity on consumer evaluation of co‐branded products
Authors: Walchli Suzanne B.
Published: October 2007

Branding studies, especially those focusing on brand extension, have often centered on establishing the relationship between consumer evaluation and the match between a product concept and the brand (concept congruity). This study introduces an additional type of congruity that arises in the evaluation of co‐branded products, the congruity between brand partners (between‐partner congruity). Between‐partner congruity has not previously been explicitly considered in the co‐branding literature, but is potentially an important influence on consumer perceptions of a brand partnership. Thus, this study represents an initial attempt to understand how the level of between‐partner congruity will affect consumer response to cobranded products. Several findings in the marketing literature have suggested that when respondents have the motivation to resolve incongruity, the relationship between congruity level and evaluation is nonmonotonic. In other words, moderately incongruent concepts are preferred to congruent or highly incongruent concepts to form an “inverted‐U” data function. Yet, when motivation to process is low, evaluation becomes less favorable in a linear fashion as incongruity increases. This study examines whether these findings can be extended to co‐branding. When concept congruity is controlled across brand pairs, the nonmonotonic relationship between between‐partner congruity level and product evaluation is observed when consumers are encouraged to elaborate on the rationale for the partnership (high involvement). However, when consumers attend to the global similarity of the partners (low involvement), product evaluation becomes less favorable as between‐partner incongruity increases. © 2007 Wiley Periodicals, Inc.
Birds of a feather flock together…definition, role and measure of congruence: An application to sponsorship
Authors: Fleck Nathalie D. , Quester Pascale
Published: October 2007

Congruence has long been discussed in the context of brand extensions and advertising, particularly in terms of celebrity endorsement. Although just as relevant for sponsorship, the examination of this concept in that context is more recent, despite evidence that it plays a significant role in determining the effectiveness of this particular communication technique. In this paper, the authors argue in favor of conceptualizing congruence as a bidimensional construct, consistent with previous research. A scale to capture this important construct is subsequently developed and validated in two separate countries. © 2007 Wiley Periodicals, Inc.
Tektin5, a new Tektin family member, is a component of the middle piece of flagella in rat spermatozoa
Authors: Murayama Emi , Yamamoto Etsuko , Kaneko Takane , Shibata Yosaburo , Inai Tetsuichiro , Iida Hiroshi
Published: October 2007

Tektins are composed of a family of filament‐forming proteins localized in cilia and flagella. Four types of mammalian Tektins have been reported, and at least two types of Tektins, Tektin2 and Tektin4, have been verified to be present in sperm flagella. A new member of the TEKTIN gene family, which was designated as rat Tektin5, was obtained by PCR technique. Rat Tektin5 cDNA consists of 1,674 bp encoding a 62.8 kDa protein of 558 amino acids. Tektin5 protein contains a Tektin domain as well as a nonapeptide signature sequence that is a prominent feature of Tektin proteins. RT‐PCR analysis indicated that Tektin5 was predominantly expressed in testis and that its expression was up‐regulated during testis development. Immunoblot analyses revealed that Tektin5 is present in sperm flagella but not in heads and that it is completely released from rat spermatozoa by 6 M urea treatment, but not extracted by 1% Triton X‐100 and 0.6 M potassium thiocyanate. Confocal laser scanning microscopy revealed that Tektin5 was located in the middle piece of flagella in rat spermatozoa with no immunolabeling in the heads and the principal piece. Immunogold electron microscopy adopting pre‐embedding method discovered that Tektin5 is predominantly associated with the inner side of the mitochondrial sheath. Tektin5 might work as a middle piece component requisite for flagellar stability and sperm motility. Mol. Reprod. Dev. 75: 650–658, 2008. © 2007 Wiley‐Liss, Inc.
Expression of hck‐tr, a truncated form of the src‐related tyrosine kinase hck, in bovine spermatozoa and testis
Authors: Bordeleau Louis‐Jean , Leclerc Pierre
Published: October 2007

In bull testicular haploid germ cells, an mRNA encoding for hck was detected in addition to another one encoding for hck‐tr, a truncated form of the tyrosine kinase hck. As the transcripts were expressed in spermatids, we tried to determine whether hck‐tr is present in mature bovine spermatozoa. Two polyclonal antibodies were produced against peptides specific to the N‐ and C‐terminal portions of the truncated protein. Western blot analyses confirmed the presence of hck‐tr in total protein extracts of ejaculated bull spermatozoa, and sub‐cellular fractionation experiments suggest its presence in both head and flagellum. The truncated protein appears tightly associated with cytoskeletal elements as it could be extracted only with SDS under reducing conditions. When assessed by indirect immunofluorescence, hck‐tr was mostly localized at the acrosomal area of the sperm cell and a similar localization was observed on demembranated spermatozoa. Immunohistochemical studies on testis sections revealed protein expression in spermatocytes as well as in round and elongating spermatids. The results presented in this study clearly show the presence of mRNAs encoding for hck and hck‐tr in testicular germ cells; hck‐tr being translated during spermatogenesis and expressed on mature ejaculated bull spermatozoa. Mol. Reprod. Dev. 75: 828–837, 2008. © 2007 Wiley‐Liss, Inc.
Relevance of caspase activity during apoptosis in pubertal rat spermatogenesis
Authors: Codelia Veronica A. , Cisternas Pablo , Moreno Ricardo D.
Published: October 2007

Caspases are a family of cysteine‐proteases, activated upon several different stimuli, which execute apoptosis in many cell death models. Previous work of our group has shown rats have the highest rate of apoptosis during the first wave of spermatogenesis (between 20 and 25 days after birth), as evaluated by TUNEL and caspase activity. However, the hierarchical order of caspase activation and the relevance of each caspase during germ cell apoptosis are not clear. Thus, the goal of this work is to take a pharmacological approach to dissect the apoptosis pathway of caspase activation. Results showed that intratesticular injection of a caspase‐8 inhibitor (z‐IETD‐fmk), or a pan‐caspase inhibitor (z‐VAD‐ fmk), significantly decreased the cleavage of p115 and PARP, two endogenous substrates of caspases, in 22‐day‐old rats. Additionally, these inhibitors promoted a significant reduction in the number of apoptotic germ cells. On the other hand, intratesticular injection of two different inhibitors of the intrinsic pathway (z‐LEHD‐fmk and minocycline) did not have any effect upon caspase substrates cleavage (p115 and PARP) or the number of apoptotic germ cells. Therefore, we conclude that the extrinsic pathway of apoptosis plays an important role in physiological germ cell apoptosis during the first round of spermatogenesis in the rat. Mol. Reprod. Dev. 75: 881–889, 2008. © 2007 Wiley‐Liss, Inc.
Effects of insulin‐like growth factor‐1 on cellular and molecular characteristics of bovine blastocysts produced in vitro
Authors: Block Jeremy , Wrenzycki Christine , Niemann Heiner , Herrmann Doris , Hansen Peter J.
Published: October 2007

Addition of insulin‐like growth factor‐1 (IGF‐1) to culture medium increases the proportion of bovine embryos that develop to the blastocyst stage and increases embryo survival following transfer to heat‐stressed, lactating dairy cows. The objective of the present study was to determine molecular and cellular correlates of these actions of IGF‐1. Embryos were produced in vitro and cultured for 7 days with or without 100 ng/ml IGF‐1. On d 7 after insemination, grade 1 expanded blastocysts were harvested and used to determine total cell number, percent apoptosis, cell allocation to the inner cell mass and trophectoderm, and the relative abundance of several developmentally important gene transcripts. There was no significant effect of IGF‐1 treatment on blastocyst cell number, the proportion of blastomeres that were apoptotic, or the number of cells in the inner cell mass and trophectoderm. However, differences in the relative abundance of several mRNA transcripts were observed between control and IGF‐1 treated embryos. Addition of IGF‐1 increased (P < 0.02) amounts of mRNA for IGF binding protein‐3 and desmocollin II and tended (P < 0.08) to increase amounts of mRNA for Na/K ATPase and Bax. Moreover, IGF‐1 treatment decreased (P < 0.05) steady‐state amounts of transcripts for heat shock protein 70 and tended (P < 0.08) to reduce amounts of IGF‐1 receptor mRNA. In conclusion, increased survival of embryos treated with IGF‐1 does not appear due to effects on cell number, percent apoptosis, or cell allocation. Addition of IGF‐1 to culture can, however, alter expression of several transcripts which may be important for embryo development and survival following transfer. Mol. Reprod. Dev. 75: 895–903, 2008. © 2007 Wiley‐Liss, Inc.
Disulfide linkage patterns of pig zona pellucida glycoproteins ZP3 and ZP4
Authors: Kanai S. , Kitayama T. , Yonezawa N. , Sawano Y. , Tanokura M. , Nakano M.
Published: October 2007

Zona pellucida, a transparent envelope surrounding the mammalian oocyte, plays major roles in fertilization and consists of three or four glycoproteins. Primary structures, and especially the positions of cysteine (Cys) residues in the zona glycoproteins, are well conserved among mammals. In this study, we analyzed the disulfide linkages of pig ZP3 and ZP4 purified from ovaries. While disulfide linkage patterns of four Cys residues in the N‐terminal halves of the ZP domains of ZP3 and ZP4 were identical to those previously reported for mice, rats, humans, and fish, the disulfide linkage patterns of six Cys residues in the C‐terminal half of the ZP domain in ZP4, as well as eight Cys residues in the C‐terminal region of the ZP domain and a following region unique to ZP3, were different from those previously reported. Thus, higher‐order structures of zona glycoproteins might not be conserved in the C‐terminal regions. Mol. Reprod. Dev. 75: 847–856, 2008. © 2007 Wiley‐Liss, Inc.
Clinical and neurophysiologic testing of the penilo‐cavernosus reflex
Authors: Podnar Simon
Published: October 2007

Aims

Both clinical and neurophysiologic testing of the penilo‐cavernosus reflex is used in clinical practice. The aim of the present study was to determine the as yet unestablished potential contribution of sacral reflex testing to the diagnostic evaluation of patients with suspected neuropathic sacral lesions.

Methods

Fifty‐three men with clinical, electrodiagnostic, and radiologic signs of chronic cauda equina or conus medullaris lesions were studied. Clinical examination, including assessment of anal sphincter tone and perianal sensation, and both clinical and neurophysiologic testing of the penilo‐cavernosus reflex, were performed. The sacral reflex was elicited on a single (normal latency: <39.4 msec) and double (<36.0 msec) electrical, and on mechanical stimulation (<35.5 msec). Responses were recorded by a concentric needle electrode inserted consecutively into the left and right bulbocavernosus muscles. The response from the more abnormal side was further analyzed.

Results

Clinical testing of the penilo‐cavernosus reflex was abnormal in 81% of patients with normal anal squeeze, in 78% with normal perianal sensation, and in 50–67% with bilaterally normal neurophysiologic findings on three different stimulation techniques. Neurophysiologic testing of the reflex was abnormal in 69–94% of patients with normal anal squeeze, in 56‐67% with normal perianal sensation, and in 44–67% of patients with a clinically normal reflex.

Conclusions

The study supported the clinical utility of both clinical and neurophysiologic measurement of the penilo‐cavernosus reflex. Neurourol. Urodynam. 27:399–402, 2008. © 2007 Wiley‐Liss, Inc.