bluuebunny/crossref_metadata_2025 huggingface dataset:
The shell region of the nucleus ovoidalis: A subdivision of the avian auditory thalamus
Authors: Durand Sarah E. , Tepper James M. , Cheng Mei‐Fang
Published: May 2005

The connectivity of a region surrounding the established thalamic auditory nuclei, n. ovoidalis (Ov) and n. semilunaris parovoidalis (SPO), was explored in the ring dove by using the anterograde tracers, Phaseolus vulgaris leucoagglutinin (PHAL) and biocytin, and the retrograde tracer, fluorogold. The Ov‐SPO surround received a projection from a cell group along the interface of the auditory midbrain and the n. intercollicularis, as revealed with PHAL and biocytin, and was composed of neurons exhibiting a common morphology. These features and the presence of overlapping projections from different portions of the Ov‐SPO surround suggest that this region comprises a functionally discrete area, which we term the Ov shell. Single unit recording within the shell established the existence of acoustically responsive units.

Both PHAL and fluorogold labeling revealed a robust projection from the Ov shell to the caudomedial hypothalamus. Major telencephalic projections of the shell terminated within the ventral paleostriatal complex, “end‐zones” of the field L, the caudomedial hyperstriatum ventrale, and regions immediately dorsal and lateral to the auditory neostriatum. Except for a portion of the shell bordering medial ovoidalis, PHAL injections into the shell also labeled fibers within the caudolateral neostriatum and along the lateral neostriatal rim.

The connectivity of the Ov shell suggests that this region may integrate auditory pathways with brain regions associated with endocrine mediated behavior. In addition, the shell may constitute a source of converging input to several levels of central auditory pathways. © 1992 Wiley‐Liss, Inc.
Development of the olivocerebellar projection in the rat: II. Matching of the developmental compartmentations of the cerebellum and inferior olive through the projection map
Authors: Wassef Marion , Cholley Béatrice , Heizmann Claus W. , Sotelo Constantino
Published: May 2005

A transient biochemical parcellation has been observed by immunocytochemical methods, during the perinatal development of both the inferior olive and the cerebellum. In the present study, we sought a relationship between this developmental compartmentation and the organization of the olivocerebellar projection. In the inferior olive, a transient parvalbumin immunoreactivity restricted to the dorsal cap of the medial accessory olive is observed around birth. The climbing fiber projection of the dorsal cap was identified in the cerebellum of newborn rats based on its parvalbumin immunoreactivity. The pattern of this projection, restricted to lobules IX and X of the vermis, and to the flocculus, is indistinguishable from that of the adult medial accessory olive, which was previously described from axonal tracing experiments. The parvalbumin immunoreactive climbing fibers were followed between birth and postnatal day 7. In the caudal vermis, Purkinje cell subpopulations can be identified between embryonic day 20 and postnatal day three, on the basis of their differential immunostaining with an antibody directed against a specific peptide, PEP 19. In lobule X, the parvalbumin immunoreactive climbing fibers form two sagittal bands on each side of the midline, one medial and one lateral. The medial parvalbumin immunoreactive climbing fiber band is coextensive with a PEP 19 negative Purkinje cell cluster, indicating a clear relationship between the biochemical parcellations of the cerebellum and inferior olive. © 1992 Wiley‐Liss, Inc.
Immunocytochemical survey of putative neurotransmitters in taste buds from Necturus maculosus
Authors: Welton Joan , Taylor Randy , Porter Angela J. , Roper Stephen D.
Published: May 2005

To investigate synaptic mechanisms in taste buds and collect information about synaptic transmission in these sensory organs, we have examined taste buds of the mudpuppy, Necturus maculosus for the presence of neurotransmitters and neuromodulators. Immunocytochemical staining at the light microscopic level revealed the presence of serotonin‐like and cholecystokinin‐like (CCK) immunoreactivity in basal cells in the taste bud. Nerve fibers innervating taste buds were immunoreactive for vasoactive intestinal peptide‐like (VIP), substance P‐like, and calcitonin gene‐related peptide‐like (CGRP) or compounds closely related to these substances. Immunoreactivity for tyrosine hydroxylase (TH) and choline acetyltransferase (ChAT) in the taste cells and nerve fibers was absent. These data suggest that serotonin, CCK, VIP, substance P, and CGRP are involved in synaptic transmission or neuromodulation in the peripheral organs of taste. No evidence was found for cholinergic or adrenergic mechanisms on the basis of the absence of immunocytochemical staining for key enzymes involved in these two transmitter systems.
Distribution of the peptide Ala‐Pro‐Gly‐Trp‐NH2 (APGWamide) in the nervous system and periphery of the snail lymnaea stagnalis as revealed by immunocytochemistry and in situ hybridization
Authors: Croll Roger P. , Van Minnen Jan
Published: May 2005

Immunocytochemistry and in situ hybridization were used to identify 200–250 central neurons that synthesize and contain the peptide APGWamide in the central nervous system of Lymnaea. The majority of these cells reside within the right anterior lobe of the cerebral ganglion and most appear to have projections to the ventral lobe of the ganglion. The neurites then branch to innervate the lobe and to send further projections into the penial nerve and to the Pelb cluster of the right pedal ganglion. The right ventral lobe also contains a cluster of about 30–40 somata, which apparently synthesize and contain APGWamide. Other populations of cells found in both the right and left anterior lobes project ipsilaterally to the pleural, parietal, and visceral ganglia. Prominent somata are also located in clusters in the visceral and right parietal ganglia. These cells project ipsilaterally into caudal neuropilar regions of the cerebral ganglia. Peripheral projections of central neurons form a dense plexus of varicose, APGWamide‐containing fibres in superficial layers of the penis and preputium. Other peripheral projections were noted in the prostate and vas deferens. No peripherally located cell bodies appeared to contain or synthesize the peptide. The results show that APGWamide is widely present in the central nervous system and male reproductive organs and suggest that it plays a major role in control of reproduction.
Morphological types of ganglion cells in the dog and wolf retina
Authors: Peichl Leo
Published: May 2005

The morphological types of ganglion cells in the dog and wolf retina were studied by intracellular staining with Lucifer Yellow. These retinae contain a range of ganglion cell types that closely correspond to those found in cat retina: alpha cells with large somata and large, relatively densely branched dendritic trees; beta cells with medium‐sized somata and small, densely branched dendritic trees; and a variety of other types with smaller somata and varying dendritic branching patterns and dendritic field sizes. The correspondence of canine and cat ganglion cell types strengthens the view that there is a common set of ganglion cell types in carnivores.

Alpha and beta cell dendritic trees of dog and wolf are monostratified in either the inner or the outer part of the inner plexiform layer, suggesting an on/off dichotomy in the response to light. Dendritic field sizes of dog alpha and beta cells increase from the central area to peripheral retina: alpha cell fields from 160–200 μm to about 1,100 μm diameter, and beta cell fields from 25 μm to about 360 μm diameter. These sizes are quantitatively very similar to those found in cat retina. The close qualitative and quantitative morphological correspondence of cat and dog ganglion cells suggests that they are also functionally very similar. It is likely that dog alpha cells have brisk‐transient (Y), and dog beta cells brisk‐sustained (X) concentric receptive fields. From the smallest beta cell sizes it is concluded that the visual acuity of the dog may be as good as that of the Cat.
Distinctive pattern of organisation in the retinofugal pathway of a marsupial: I. Retina and optic nerve
Authors: Harman A. M. , Jeffery Glen
Published: May 2005

The nasotemporal division in the retina and the pattern of crossed and uncrossed axons in the optic nerve were determined in an Australian marsupial, a wallaby, Setonix brachyurus (the quokka), following unilateral horseradish peroxidase injections into primary visual centres. The gross morphology of the nerve was also examined. Ipsilaterally projecting ganglion cells were restricted to the temporal retina, whereas those that project contralaterally were located in all retinal regions. The morphological study of the nerve showed that fasciculation patterns, evident along much of the length of the nerve, became indistinct centrally and were replaced in the prechiasmatic region by dorsoventrally oriented fissures. In this prechiasmatic region, axons were oriented in two directions. Whereas the majority were aligned centroperipherally with the long axis of the nerve, a proportion were aligned dorsoventrally in the fissures. Labelling with HRP revealed that uncrossed axons were restricted to the lateral region of the optic nerve and possibly to discrete fascicles, whereas those destined to cross at the chiasm occupied all regions of the nerve but were less dense on the lateral side. This spatial distribution of crossed and uncrossed projections did not change along the length of the nerve. These results demonstrate that fibre organisation in the marsupial optic nerve is different than that found in eutherian mammals. © 1992 Wiley‐Liss, Inc.
Distinctive pattern of organisation in the retinofugal pathway of a marsupial: II. Optic chiasm
Authors: Jeffery Glen , Harman A. M.
Published: May 2005

In the mammalian optic chiasm retinal axons from each eye divide into two populations, those that decussate and those that remain uncrossed. In eutherian (placental) mammals, the separation of these pathways is not reflected in the structure of the chiasm. The two populations from each eye are mixed through each hemichiasm, segregating only at the midline, where the uncrossed projection turns back.

In this study the optic chiasm of a marsupial, the wallaby, Setonix brachyurus (quokka) has been investigated with staining and neuronal tracing techniques. The chiasm of this mammal is quite different from that of eutherian mammals. In coronal section it can be morphologically subdivided into three regions, a central body in which fasciculated groups of axons from each eye interdigitate across the midline, and two distinct lateral regions, one on each side, which contain the uncrossed retinal projections. In the rostral chiasm the lateral regions are separated from the main body of the chiasm by vertically oriented fibre‐free regions. Caudally, the lateral regions increase in size and become less distinct as increasing numbers of contralaterally projecting axons that have crossed the midline project into them. However, the two populations remain predominantly segregated in this region. As the lateral regions develop, the central body of the chiasm becomes thinner and finally detaches at the midline to form the two optic tracts.

The routes taken by retinal axons through the eutherian and marsupial chiasm appear to be fundamentally different. Therefore, the developmental factors that determine the laterality of retinal projections are likely to show significant differences in the two mammalian groups. © 1992 Wiley‐Liss, Inc.
Patterns of transmitter labelling and connectivity of the cat's nucleus of Darkschewitsch: A wheat germ agglutinin‐horseradish peroxidase and immunocytochemical study at light and electron microscopical levels
Authors: Onodera Satoru , Hicks T. Philip
Published: May 2005

Immunocytochemical studies using antibodies raised against a number of probable synaptic transmitters of the mesodiencephalic area, and fibre‐tracing studies using wheat germ agglutinin‐horseradish peroxidase (WGA‐HRP), have been performed in adult cats. Glutamate and aspartate immunoreactivity produced a strong labelling of many cell bodies and terminals in the nucleus of Darkschewitsch (ND). γ‐Aminobutyrate (GABA) immunoreactivity in the ND appeared as a moderate label in some small neurones, and as a strong label in a few glial‐like cells, in addition to being present in high levels to produce strong labelling in many GABA‐immunopositive terminals that possessed pleomorphic vesicles. Some choline acetyltrans ferase‐positive terminals and dendrites and a few substance P‐positive fine fibres possessing varicosities also were observed in the ND.

Following WGA‐HRP injection in the ND, dense terminal labelling was seen ipsilaterally in the rostral half of the medial accessory olive, suggesting that there may be a certain degree of mediolateral and dorsoventral topographic correspondance within the ND‐olive projection. In the same cases, many cell bodies containing HRP reaction product also were found (1) ipsilaterally in the motor cortex, anterior pretectal nucleus, and a restricted area of the caudal part of the substantia nigra pars reticulata; (2) contralaterally in the anterior and posterior interposed cerebellar nuclei as well as in a portion of the lateral cerebellar nucleu and (3) bilaterally in the zona incerta, the posterior pretectal nucleus, the pedunculopontine tegmental nuclei, the spinal trigeminal nucleus, the dorsal column nuclei, and the spinal cord. Details of the interrelationships and functional considerations amongst the ND, adjacent nuclei, and longitudinal zones of the cerebellum are discussed. © 1995 Wiley‐Liss, Inc.
Sound stimulation induces Fos‐related antigens in cells with common morphological properties throughout the auditory brainstem
Authors: Adams Joe C.
Published: May 2005

Cells within the auditory brainstem of cat that respond to sound by producing the transcription factor Fos or related proteins were identified by immunostaining with antisera against Fos and Zif/268. Within the cochlear nucleus, all antisera showed similar staining patterns, however, in the superior olive and inferior colliculus, staining patterns differed between antisera. Immunostained cells were characterized by their size, location, by the presence of perisomatic terminals that immunostained for glutamate decarboxylase or synaptophysin, or by electron microscopy. Most cell classes were not immunopositive. In the ventral cochlear nucleus, roughly 99% of Fos‐positive cells had few perisomatic terminals. Within the superior olivary complex (SOC), the majority of immunopositive cells had few perisomatic terminals. Lateral olivocochlear cells were identified as Fos positive by their size, location, lack of perisomatic terminals, and positive costaining for acetylcholinesterase as evidenced by a novel reaction product. This report appears to be the first demonstration of these cells responding to sound stimulation. Within the inferior colliculus, bands of positive cells produced by tonal stimulation extended from the central nucleus throughout the dorsal cortex and the posterior pericentral region, a finding unexpected on the basis of previous electrophysiological recordings and anatomical studies of ascending inputs to the colliculus. Approximately 35% of Fos‐positive cells in the inferior colliculus had plentiful perisomatic terminals. Results demonstrate a high degree of specificity of auditory cell types that respond to sound by producing Fos‐like proteins and show that previously intractable physiological questions can be addressed by assaying for sound‐induced production of these antigens. © 1995 Wiley‐Liss, Inc.
Differential localization of NMDA and AMPA receptor subunits in the lateral and basal nuclei of the amygdala: A light and electron microscopic study
Authors: Farb C. R. , Aoki C. , Ledoux J. E.
Published: May 2005

Anatomical and physiological studies indicate that the amino acid L‐glutamate is the excitatory transmitter in sensory afferent pathways to the amygdala and in intraamygdala circuits involving the lateral and basal nuclei. The regional, cellular, and subcellular immunocytochemical localizations of N‐methyl‐D‐aspartate (NMDA) and L‐α‐amino‐3–hydroxy‐5–methyl‐ 4–isoxazole propionate (AMPA), two major classes of glutamate receptors, were examined in these areas of the amygdala. A monoclonal antibody and a polyclonal antiserum directed against the R1 subunit of the NMDA receptor were used. Each immunoreagent produced distinct distributions of perikaryal and neuropilar staining. Dendritic immunoreactivity was localized primarily to asymmetric (excitatory) synaptic junctions, mostly on spines, consistent with the conventional view of the organization and function of NMDA receptors. Whereas the anti‐NMDAR1 antiserum produced sparse presynaptic axon terminal labeling and extensive glial labeling, the anti‐NMDAR1 antibody labeled considerably fewer glia and many more presynaptic axon terminals. Labeled presynaptic terminals formed asymmetric and symmetric synapses, suggesting presynaptic regulation of both excitatory and inhibitory transmission. Immunoreactivity for different subunits of the AMPA receptor (GluR1, GluR2/3, and GluR4) was uniquely distributed across neuronal populations, and some receptor subunits were specific to certain cell types. Immunoreactivity for GluR1 and Glu2/3 was predominately localized to dendritic shafts and was more extensive than that of GluR4 due to heavy labeling of proximal portions of dendrites. The distribution of GluR4 immunoreactivity was similar to NMDAR1: GluR4 was seen in presynaptic terminals, glia, and dendrites and was primarily localized to spines. The presynaptic localization of GluR4 in the absence of GluR2 suggests glutamate. mediated modulation of presynaptic Ca++ concentrations. These data add to our understanding of the morphological basis of pre‐ and postsynaptic transmission mechanisms and synaptic plasticity in the amygdala. © Wiley‐Liss, Inc.
Childhood origins of antisocial behavior
Authors: Farrington David P.
Published: May 2005

The major early risk factors for antisocial behavior include impulsiveness, low intelligence and low school achievement, poor parental supervision, child physical abuse, punitive or erratic parental dis‐cipline, cold parental attitude, parental conflict, disrupted families, antisocial parents, large family size, low family income, antisocial peers, high delinquency‐rate schools, and high crime neighborhoods. The causal mechanisms linking these risk factors with antisocial outcomes are less well established, and the ‘ICAP’ theory is proposed to explain these. The major implications for intervention are that programs targeting these key risk factors should be implemented, especially multiple‐component community‐based programs. Copyright © 2005 John Wiley & Sons, Ltd.
Parental rearing styles and personality disorders in prisoners and forensic patients
Authors: Timmerman Irma G. H. , Emmelkamp Paul M. G.
Published: May 2005

In the present study it was hypothesized that men with a criminal status (forensic inpatients and prisoners) would report more pathological rearing styles of their parents than men from the general population, after accounting for the influence of personality pathology. The results showed that forensic inpatients reported significantly less care from their mothers and more protection from both parents. No differences on paternal care were found though. The prisoners were less clearly distinguished from normal controls with respect to parental rearing. They perceived their fathers as more protective, however, only when the influence of the personality disorder category was controlled for and not when the influence of personality disorder features was controlled for. Further, prisoners perceived their mothers as significantly more caring. The results with respect to criminal and patient status stayed the same after controlling for the influence of personality pathology. The analyses further showed that cluster B pathology when measured as one construct was significantly associated with all parental rearing variables: less care and more protection. Also, cluster A and cluster C pathology, criminal status and inpatients status did not influence these results. When the cluster B disorders were examined separately though, a less clear picture emerged. The categorical defined borderline personality disorder was significantly related to all four rearing variables: less care and more protection. For cluster C pathology the opposite was found: when measured categorically no significant relations with rearing were found and when measured dimensionally all relations were significant. When measured dimensionally, antisocial personality features were significantly associated with less care from both parents and with more protection from the mother. When measured categorically, only the relationship with care of father remained significant. Finally, cluster A pathology was related significantly only to (low) maternal care. Copyright © 2005 John Wiley & Sons, Ltd.
Silica Monolayer Solid‐Acid Catalyst Prepared by CVD
Authors: Katada Naonobu , Niwa Miki
Published: May 2005

For the design of novel acid catalysts it is important to understand the principles of the generation of acidity. However, the origin of this acidity is unclear because the mixed solid‐acid usually possesses a complicated structure leading to different types of sites. The CVD of silica is being used on high surface area basic oxides to provide model compounds to elucidate the formation and functioning of acid catalysts. This paper reviews these studies and also shows how novel heat resistant catalysts can be obtained.
Nootropics: Myth or reality?
Authors: Kanowski S.
Published: May 2005

Dr. Kanowski, S.: Nootropics: Myth or reality? Drug Dev. Res. 2:433–439, 1982.

Through the ages there have been two strong human motivations: to remain on this earth as long as possible, and to maintain or regain one's youth and activities in one's old age. The fountain of youth is an ancient mythological version of this strong desire. The question arises, whether “nootropics” is a modern one. For a clear understanding it is necessary to distinguish between geroprophylactica and gerotherapeutica. The extent to which promising models for the development of gerotherapeutica do exist and the value of currently existing gerotherapeutica will be points of discussion. Strong emphasis will be given to the difference between statistical significance and clinical relevance in the clinical evaluation of the latter.
Attachment formation and separation in heterosexually naive preadult rhesus monkeys (Macaca mulatta)
Authors: Erwin J. , Brandt E. M. , Mitchell G.
Published: May 2005

Six heterosexual pairs of 3‐yr‐old rhesus monkeys which had no previous experience with other‐sexed peers were allowed 1, 2, or 3 weeks to form social attachments. Attachment strength was evaluated by observation of the subjects' responses to seperation and reunion. Those pairs which were together for the shortest period of time exhibited the greatest amount of disturbance at separation, but they were also the most distrubed prior to separation and at reunion. The behavior of females was influenced more by length of pairing than was the behavior of males.
Morphological, biochemical, and functional changes in chick embryonic brain tissue after intracerebral administration of ouabain
Authors: Sedláček Jindřcih , Šťastný František
Published: May 2005

The manifestations of intracerebral administration of 3.4 × 10−4 M ouabain were studied in 15‐ and 19‐day‐old chick embryos. No significant changes in the histological structure of the cerebrum were detected in 15‐day‐old embyros. The (Na+–K+)‐ATPase activity was completely suppressed, however, and the spontaneous bioelectric activity was inhibited. In 19‐day‐old embyros distinct swelling and vacuolization of the cellular elements occurred. The (Na+–K+)‐ATPase activity was inhibited to the same extent in 19‐day‐old as in 15‐day‐old cerebral tissue. Ouabain administration resulted in episodes of spike‐and‐wave paroxysmal activity in the EEG of 19‐day‐old embyros, characterized by high amplitude and low frequency discharges. Spontaneous motor activity was inhibited following an initial transient increase. In some cases short episodes of hyperactivity were registered, regularly followed by complete inactivity.
A comprehensive classification system for lipids
Authors: Fahy Eoin , Subramaniam Shankar , Brown H. Alex , Glass Christopher K. , Merrill Alfred H. , Murphy Robert C. , Raetz Christian R. H. , Russell David W. , Seyama Yousuke , Shaw Walter , Shimizu Takao , Spener Friedrich , van Meer Gerrit , VanNieuwenhze Michael S. , White Stephen H. , Witztum Joseph L. , Dennis Edward A.
Published: May 2005

Lipids are produced, transported, and recognized by the concerted actions of numerous enzymes, binding proteins, and receptors. A comprehensive analysis of lipid molecules, “lipidomics,” in the context of genomics and proteomics is crucial to understanding cellular physiology and pathology; consequently, lipid biology has become a major research target of the postgenomic revolution and systems biology. To facilitate international communication about lipids, a comprehensive classification of lipids with a common platform that is compatible with informatics requirements has been developed to deal with the massive amounts of data that will be generated by our lipid community. As an initial step in this development, we divide lipids into eight categories (fatty acyls, glycerolipids, glycerophospholipids, sphingolipids, sterol lipids, prenol lipids, saccharolipids, and polyketides) containing distinct classes and subclasses of molecules, devise a common manner of representing the chemical structures of individual lipids and their derivatives, and provide a 12 digit identifier for each unique lipid molecule. The lipid classification scheme is chemically based and driven by the distinct hydrophobic and hydrophilic elements that compose the lipid. This structured vocabulary will facilitate the systematization of lipid biology and enable the cataloging of lipids and their properties in a way that is compatible with other macromolecular databases.[Reprinted with copyright permission from the Journal of Lipid Research. 2005. 46: 839–861.]
First Lewis Acid Catalyzed Generation and Reaction of α‐Organylsulfanyl and α‐Organylselanyl Carbenium Ions Using Ethyl α‐Fluoroacetate Derivatives
Authors: Yoshimatsu Mitsuhiro , Kawamoto Masayo , Gotoh Kohei
Published: May 2005

Lewis acid catalyzed generation and reactions of α‐organylsulfanyl and α‐organylselanyl carbenium ions with nucleophiles proceeded in high yields using α‐fluoro‐α‐organylsulfanyl‐ and α‐fluoro‐α‐organylselanylacetate and 5 mol‐% scandium triflate. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)
Cholesterol biosensors prepared by electropolymerization of pyrrole
Authors: Trettnak Wolfgang , Lionti Ilaria , Mascini Marco
Published: May 2005

Biosensors for cholesterol were prepared by electropolymerization of pyrrole in solutions of 0.1 M phosphate buffer containing 10 mM NaClO4 and 15 to 55 IU/mL of cholesterol oxidase at a potential of 800 mV versus a calomel reference electrode (3 M KCl). The sensors were tested for their response toward cholesterol in batch, flow‐through, and flow‐injection systems by detection of the hydrogen peroxide formed in the enzymatic reaction. Flow‐injection analysis (FIA) measurements with an injection loop of 50 μL were performed with a high reproducibility in the range of 0 to 250 μM cholesterol with solutions of constant detergent concentration (1% Triton X‐100 in 0.1 M phosphate buffer of pH 7.0) and at a flow rate of 0.2 mL/min. At this flow rate, the detection limit was approximately 5 μM cholesterol and the sample throughput was 25 injections per hour. The response of the sensors toward ascorbic and uric acid was investigated.
Gold ultramicroelectrodes for on‐site monitoring of trace lead
Authors: Wang Joseph , Tian Baomin
Published: May 2005

Gold and gold‐coated cylinder microelectrodes are used as stripping‐based microsensors for trace lead. These gold ultramicroelectrodes exhibit a favorable stripping performance, similar to that observed at common mercury ultramicroelectrodes. Such use of “mercury‐free” electrodes greatly facilitates the development of disposable sensors for lead blood screening programs. Potentiometric stripping analysis at these gold ultramicroelectrodes yields reproducible results for parts per billion (μg/L) concentrations of lead, following short preconcentration periods and using static, nondeaerated solutions. Numerous experimental variables have been characterized and optimized. Repetitive assays of 200‐μl sample drops yield a relative standard deviation of 2.2% (n = 20). The application of the gold ultramicroelectrodes for assays of various real samples is demonstrated, and prospects for their use in decentralized testings are discussed.
Ion pairing and acid dissociation constants in poly(vinyl chloride)‐based ion‐selective electrode membranes
Authors: Verpoorte Elisabeth M. J. , Chan Andy D. C. , Harrison D. Jed
Published: May 2005

Ion pairing and acid dissociation constants, as well as limiting conductances, have been estimated in ion‐selective electrode membranes based on a 33 wt% poly(vinyl chloride) (PVC), 66 wt% dioctyladipate matrix using the Fuoss equation of conductance for weakly dissociable species. Dissociation constants of 1.66, 3.51, and 0.69 × 10−5 were determined for NaClO4, C6H5COOK (KBz), and benzoic acid (HBz), respectively, in a membrane matrix with 1% valinomycin and 0.01% KB(C6H5)4 present as additives. The first two values are consistent with tight ion pairing in a low dielectric solvent and indicate no special role for PVC in ion solvation. The weak acid dissociation is 4 to 5 orders of magnitude higher than expected; HBz also shows unusual interactions with the membrane matrix at low added concentrations. The effect of HBz and methylbenzoate (MeBz) on surface charge transfer resistance and membrane bulk resistance shows that HBz is dissociating to form ions, and a possible mechanism for the unusual interactions has been deduced. MeBz caused a significant increase in surface charge transfer resistance, indicating a mechanism by which membrane permeation by lipophilic, neutral components of biological samples could degrade sensor performance.
Rare earth ion selective electrodes
Authors: Zhang Yonghua , Wu Jinlan , Wang Erkang
Published: May 2005

In this article, we report the rare earth ion selective electrodes developed in our laboratory. Rare earth containing functional copolymers, rare earth oxides, and chelates have been used as active materials. Methods for preparing raw materials, behavior of electrodes, and application of rare earth ion selective electrodes in flow injection analysis have been discussed as well.
Evidence for the functional mechanism of a polypyrrole glucose oxidase electrode
Authors: Cooper Jonathan M. , Bloor David
Published: May 2005

One attractive prospect for the use of conducting polymers in the design of amperometric biosensors is that it has been thought possible to arrange for direct electron transfer between entrapped enzymes and “molecular wires” within the polymer. In this article, we investigate the mechanism of an amperometric enzyme electrode based upon the immobilization of the redox enzyme glucose oxidase (GOD) within the conducting polymer, polypyrrole (Ppy). We present evidence that electron transport between GOD and the electrode surface is due to the electrocatalytical oxidation of hydrogen peroxide, which suggests that if direct electron transfer between the enzyme and Ppy does occur, it is, at best, very inefficient.
Simultaneous determination of phosphate and pyrophosphate by an amperometric flow‐injection system with immobilized enzyme reactors
Authors: Yao Toshio , Wasa Tamotsu
Published: May 2005

A bioamperometric flow‐injection system is proposed for the simultaneous determination of phosphate and pyrophosphate. The injected sample is split so that part passes through an immobilized inorganic pyrophosphatase reactor before passing through a coimmobilized nucleoside phosphorylase‐xanthine oxidase reactor. The other portion passes only through the latter reactor. Because each channel has a different residence time, two peaks are obtained. The first peak corresponds to phosphate and the second peak to the total phosphate (phosphate plus pyrophosphate). The maximum currents of both peaks are linearly related to the concentration of phosphate and total phosphate, respectively; 20 samples per hour can be processed with an RSD < 1.5%.
Batch injection analysis with adsorptive stripping voltammetry for the determination of traces of nickel and cobalt
Authors: Brett Christopher M. A. , Brett Ana Maria Oliveira , Tugulea Laura
Published: May 2005

Square wave adsorptive stripping voltammetry (AdSV) in conjunction with the batch injection analysis technique has been investigated at mercury thin‐film electrodes, using analysis of nickel and cobalt ions with nioxime ligand as example, and injection of sample volumes of ≤100μL. Experiments were conducted in a HEPES neutral buffered medium, suitable for analysis of biological fluids. Sensitivity is maximized by continuing the adsorptive accumulation after the end of the injection period, and employing the lowest possible injection rate from the electronic micropipette of 24.5μLs−1. The practical detection limit is 5 nM for nickel and 2 nM for cobalt. Comparison is made with batch injection analysis with anodic stripping voltammetry and the merits of the technique relative to continuous flow‐through methods are assessed.
Determination of trace europium by adsorptive cathodic stripping voltammetry after complexation with cupferron
Authors: Abollino Ornella , Aceto Maurizio , Mentasti Edoardo , Sarzanini Corrado , van den Berg Constant M. G.
Published: May 2005

This article describes the determination of Eu by adsorptive cathodic stripping voltammetry after complexation with N‐nitroso‐N‐phenylhydroxylamine (cupferron). The accumulation of the complex at the HMDE was performed at 0.0 V and the subsequent potential scan was made in the square wave mode. The analyte signal occurred at −0.88 V. The detection limit is 0.06 nmol dm−3. The effect of instrumental and chemical parameters on the peak height and potential was investigated. The same technique can be used for the determination of ytterbium and of the other rare earth elements (REEs) after separation.
Voltammetric determination of ubiquinone adsorption at mercury electrodes
Authors: Wittstock Gunther , Emons Hendrik
Published: May 2005

Adsorption isotherms of the ubiquinones UQ4, UQ6, UQ9 and UQ10 have been determined by two independent voltammetric techniques at the stationary mercury/solution interface. While the redox behavior is essentially the same for all homologues investigated, the molar free enthalpy of adsorption ΔAG increases steadily with the number of isoprenic units from UQ4 to UQ10. In case of UQ10, the experiments have been carried out with three different potentiostatic systems. This allows one to estimate the accuracy of the methods which are direct ones and do not require calibration.
Amperometric detection of electroinactive anions using conducting polymer electrodes subsequent to chromatographic separation
Authors: Barisci J. N. , Wallace G. G. , Clarke A.
Published: May 2005

The use of a chloride‐containing polypyrrole electrode for the amperometric detection of electroinactive anions subsequent to separation by ion chromatography in suppressed, low conductivity eluent is described. It is demonstrated that changes in selectivity can be obtained by the application of different potential waveforms and current sampling protocols. The approach described is based on the anion dependence of the oxidation/reduction kinetics of the conducting polymer film induced by the applied potential.
Electrochemical behavior of the C60–γ‐cyclodextrin inclusion complex (1:1) on HMDE in an aqueous solution
Authors: Li Mei‐Xian , Li Nan‐Qiang , Gu Zhen‐Nan , Zhou Xi‐Huang , Sun Yi‐Liang , Wu Yong‐Qing
Published: May 2005

The electrochemical behavior of the water‐soluble C60–γ‐CD (1:1) inclusion complex has been studied on the hanging mercury drop electrode. A one‐electron reversible adsorptive electroreduction and three irreversible adsorptive electroreductions were detected by cyclic voltammetry. The amount of C60–γ‐CD adsorbed at saturation is 1.73 × 10−11 mol/cm2, the diffusion coefficient is 5.81 × 10−6 cm2/s, and the standard rate constant of the surface reaction ks are 0.888 s−1, 0.853 s−1 and 1.032 s−1, respectively.
Numerical simulation of electrophoresis: The complete solution for three isotachophoretic systems
Authors: Radi Peter , Schumacher Ernst
Published: May 2005

Numerical integrations of the partial differential equations describing the time and spatial evolution of isotachophoresis were performed on three different systems, in one case involving reaction kinetics to investigate weak electrolytes.
Application of the immunoblotting technique to the study of single protein species in complex biological fluids: A model study with alpha‐2‐macroglobulin
Authors: Folkersen Jørgen , Sim Robert B. , Sottrup‐Jensen Lars , Svehag Sven‐Erik
Published: May 2005

Sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, and the immunoblotting technique, were applied to structural analysis of a single protein (alpha‐2‐macroglobulin, α‐2‐M) in human serum or plasma without prior purification of this protein. The use of immunoglobulin fractions of four monospecific polyclonal antibody preparations to α‐2‐M in the immunoblotting step showed marked unspecific binding to the proteins fixed onto nitrocellulose. Immunospecific purification of the antibodies by two different methods, and the introduction of biotinylated antibodies and avidin‐peroxidase, removed the background binding. When reduced proteins were fixed onto nitrocellulose a quantitative loss of α‐2‐M antigen reactivity was observed, compared to identical nonreduced samples. The degradation pattern of α‐2‐M in serum or plasma corresponded to the pattern observed with purified α‐2‐M. Thus, the described immunoblotting technique, applied directly to serum or plasma, could detect all not heat‐denaturated α‐2‐M products as seen on Coomassie‐stained polyacrylamide gels when analyzing purified α‐2‐M.
Isoelectric focusing and non‐isoelectric precipitation of ferritin in immobilized pH gradients: An improved protocol overcoming protein‐matrix interactions
Authors: Righetti Pier Giorgio , Gelfi Cecilia , Bossi Maria Luisa , Boschetti Egisto
Published: May 2005

It has been impossible, up to now, to focus ferritin (a large, ca. 450 000 Da, ironstorage protein ubiquitous in mammalian systems) in immobilized pH gradients (IPG). This was not a sieving problem, as ferritin focuses readily in a 4%T polyacrylamide (or polytrisacryl) gel in conventional carrier ampholyte isoelectric focusing. A strong interaction with the IPG matrix was suspected, but an auto‐buffered (pH 6.0) soluble IPG polymer failed to precipitate ferritin from solution, although it altered its visible spectrum, suggesting the formation of soluble complexes. By a Takeo plot, the dissociation constant (Kd)of the ferritin‐IPG matrix complex was estimated to be 0.1 mM. However, even a 100‐fold dilution of Immobilines into the IPG matrix with a concomitant addition of competing ions (up to 3 % carrier ampholytes) failed to produce good focusing patterns. An unsuspected, hitherto un‐reported, precipitating power of free Immobilines in solution on the ferritin macroion was found to be the key to the riddle. The precipitating ions are (in order of aggregation power): pK 9.3 > pK 7.0 > pK 6.2. None of the acidic Immobilines (pKs 3.6, 4.4 and 4.6) and, among the basic, only the pK 8.5, exhibit any precipitation power on ferritin and other complex protein mixtures. In a new IPG pH 4–5 interval, containing only the pK 4.6 as buffering and the pK 8.5 Immobilines as titrant ions, excellent focusing patterns of ferritin were obtained. It is hypothesized that the precipitating Immobilines act as cationic detergents, and are able to cross‐link macroions with a mixed‐type, hydrophobic‐ionic interaction at the two extremities of the molecule. Guidelines are given for handling this major problem on a short‐term basis, the longterm goal being the replacement of the ‘unfavorable’ Immobilines (pKs 9.3, 7.0 and 6.2) by new chemical structures of the desirable type (the non‐precipitating pK 8.5 species).
Cyanogen bromide‐activated nitrocellulose membranes: A new tool for immunoprint techniques
Authors: Demeulemester Claude , Peltre Gabriel , Laurent Micheline , Panheleux Dominique , David Bernard
Published: May 2005

Nitrocellulose membranes were activated by cyanogen bromide in order to improve their binding capacities. Crude extracts of a grass pollen, Dactylis glomerata, and a mite, Dermatophagoides farinae, were separated by isoelectric focusing in agarose and blotted by capillary transfer onto nitrocellulose or activated nitrocellulose. The Dermatophagoides farinae components were visualized by Coomassie Brilliant Blue, India ink or Aurodye staining. The Dactylis glomerata and Dermatophagoides farinae allergens were revealed by radioimmunodetection using sera from allergic patients. A great increase of allergen binding was observed visually and by radioactive counting on activated nitrocellulose as compared with untreated nitrocellulose. New allergens which were not detectable on nitrocellulose appeared on activated nitrocellulose.
Studies on the heterogeneity of anti‐hapten antibodies by means of two‐dimensional affinity electrophoresis
Authors: Takeo Kazusuke , Tanaka Tatehiko , Nakamura Kazuyuki , Suzuno Ryosuke
Published: May 2005

The molecular heterogeneity of rabbit anti‐hapten antibodies has been investigated by two‐dimensional affinity electrophoresis (2D‐AEP). Anti‐dansyl and anti‐arsanilic diazo‐antibodies were separated into several hundred IgG spots as in the case of anti‐DNP antibodies. They were grouped into a number of monoclonal IgG families. At the beginning of immunization, IgG spots having low pI and low affinity were predominant but one or two weeks after immunization the IgG spots with high affinity and high pI increased. After the second or third immunization, the 2D‐AEP patterns became stable and constant. Anti‐arsanilic diazo and anti‐DNP antibodies exhibited only weak cross‐reactivity with other aromatic haptens. In contrast, anti‐dansyl antibodies cross‐reacted to a considerable degree with DNP‐hapten. A few anti‐dansyl IgG families which have cross‐reactivity with DNP‐hapten were separated. Their apparent dissociation constants to the haptens and their affinity ratios were calculated from their 2D‐AEP patterns, according to the affinity theory.
Concanavalin A crossed affinity immunoelectrophoresis and image analysis for semiquantitative evaluation of microheterogeneity profiles of human serum transferrin from alcoholics and normal individuals
Authors: Heegaard Niels H. H. , Hagerup Martin , Thomsen Åge C. , Heegaard Peter M. H.
Published: May 2005

The microheterogeneity profile of human serum transferrin from normal and alcoholic subjects was investigated qualitatively and quantitatively by means of Concanavalin A crossed affinity immunoelectrophoresis and an image analysis program. Differences in amounts of nonreacting transferrin molecules were found, suggesting an increase in triantennary glycosylation of transferrin from alcoholics compared with normal individuals. The increased amount of a highly retarded fraction in crude sera from alcoholics was demonstrated to be artefactual, probably due to entrapment or coprecipitation as the fraction disappeared after repeating the analysis with immunosorbent‐purified transferrin. In conclusion, affinity electrophoresis represents a simple approach for demonstration of variations in the neutral monosaccharides of glycans and can discriminate between transferrin from alcoholics and normal individuals.
Affinophoresis of red blood cells: Surface antigen‐specific acceleration of electrophoresis
Authors: Shimura Kiyohito , Ogasawara Norikazu , Kasai Ken‐ichi
Published: May 2005

A method employing the technique of affinophoresis to increase the electrophoretic mobility of specific cells according to their surface antigens was developed. Red blood cells were treated consecutively with the maximum subagglutinating dose of an antired blood cell serum, a biotinylated second antibody, avidin and finally with a negatively charged biotin‐affinophore which was prepared by coupling biotin to polylysine (average degree of polymerization, 270 or 1150), followed by complete succinylation. The electrophoretic mobility of cells was analyzed with an automatic cell electrophoresis analyzer. The use of a homologous anti‐serum increased the electrophoretic mobility of rabbit, human and rat red blood cells by 2.9, 1.7 and 1.6 times, respectively. A larger affinophore containing fewer biotin moieties was more effective. In the case of a mixture of red blood cells from two species, cells from only one species could be accelerated by using homologous antiserum, e.g., affinophoresis of a mixture of human and rat red blood cells by using either homologous antiserum gave two separate peaks on the histogram, whereas a single peak would be obtained in usual electrophoresis because there is little difference in the original migration velocities of the two cell types.
DNA sequencing in HydroLink matrices: Extension of reading ability to > 600 nucleotides
Authors: Gelfi Cecilia , Canali Alessandra , Righetti Pier Ciorgio , Vezzoni Paolo , Smith Carolyn , Mellon Mark , Jain Tikam , Shorr Robert
Published: May 2005

All the systems for optimizing DNA sequencing published so far have introduced modifications regarding: (i) linearization of band migration via ionic strength gradients or wedge‐shaped gels; (ii) automatization of band reading via introduction of fluorescent probes; (iii) direct blotting analysis; (iv) pulsed electric fields and (v) discontinuous buffer systems. In all these systems, DNA sequence reading with an accuracy of ca. 98 % rarely exceeds a length of 350 bases. We have chosen, in order to increase the reading ability of a single gel, to manipulate the characteristics of the gel matrix. The Seq‐HydroLink gel formulation here reported allows optimal reading, from a single gel run, of at least 600 bases. In order to guarantee this reading ability in a single run, the upper and lower ends of the ladder are time‐resolved, i. e. the same sample is applied to the gel matrix at three different time intervals. The present system represents an increase of at least 30 % in reading ability as compared with any type of polyacrylamide gel formulation so far reported.
Isoproteins and an isoelectric focusing mutant of human apoprotein serum amyloid A
Authors: Steinmetz Armin , Schmidt Barbara , Hocke Gerti , Motzny Sabine , Vitt Herbert , Kaffarnik Hans
Published: May 2005

On isoelectric focusing of human plasma and subsequent immunoblotting, using antii‐human serum amyloid A (SAA) antibodies, a genetic variant of SAA was detected in a family of Turkish origin. All affected members of the family were apparent heterozygotes or the mutant protein, which underwent a charge shift of about one charge unit toward the anode. The variant is likely to be a mutant of the most prominent forms of SAA (SAA1 and SAA2, or SAA1 and SAA1 des Arg). The appearance of a genetic variant of two of the six reported SAA‐isoforms in human plasma supports the concept of SAA proteins being products of different genes.