bluuebunny/crossref_metadata_2025 huggingface dataset:
Basic Fibroblast Growth Factor in the Adrenal Gland
Authors: Blottner Dieter , Westermann Reiner , Grothe Claudia , Böhlen Peter , Unsicker Klaus
Published: April 2006

The importance of trophic agents for the development and maintenance of neurons and their presence in mesenchyme‐derived neuronal target organs such as muscle is well exemplified by the protein nerve growth factor (NGF) and its synthesis in target areas of sympathetic and sensory nerves. Stringent conceptualization of target organ‐regulated neuronal maintenance would imply that neurons were able to provide trophic support to their presynaptic counterparts. We present data suggesting that basic fibroblast growth factor (bFGF), a mitogen and trophic factor for several neuron populations in vitro, may be such a protein involved in retrograde trophic neuron‐neuron interaction. Basic FGF or a closely related protein is present in the adrenal medulla and its sympathetic neuron‐like chromaffin cells. A polyclonal antibody specific for bFGF recognizes an 18 kD band in Western blots of bFGF‐enriched bovine adrenal medulla extracts and immunostains isolated bovine chromaffin cells. This antibody also blocks the bFGF‐like activity present in adrenal medullary extracts and chromaffin granule extracts that both promote in vitro survival of embryonic chick ciliary ganglionic neurons. Furthermore, like bFGF, the soluble proteins of bovine chromaffin granules are mitogenic for cultured bovine aorta endothelial cells. Electrothermal unilateral destruction of the adrenal medulla causes the disappearance of 25% of Nissl‐stained neurons in the ipsilateral intermediolateral column (IML) of the spinal cord between levels Th7 and L1, which contains the preganglionic neurons projecting to the adrenal medulla. Substitution of the adrenal medulla by gel foams soaked with bFGF prevents neuron losses in the IML. The effects are specific in that NGF and cytochrome C are ineffective. Our results suggest that bFGF is located in chromaffin cells and maintains target‐deprived autonomic spinal cord neurons, thus possibly acting as an interneuronal trophic messenger in vivo.
Climbing Fibre Plasticity in the Cerebellum of the Adult Rat
Authors: Rossi F. , Wiklund L. , van der Want J. J. L. , Strata P.
Published: April 2006

The present paper reports an example of collateral sprouting, and provides a detailed morphological description of newly formed axonal branches, terminal arborizations, and synapses in the central nervous system of an adult mammal. By means of the anterograde tracer Phaseolus vulgaris leucoagglutinin (PHA‐L), we demonstrate that the climbing fibres, which survive a subtotal lesion of the inferior olive in the rat, emit collateral sprouts and develop new terminal plexuses forming new synaptic contacts on Purkinje cell dendrites. Adult climbing fibres thus show striking plastic capabilities that represent the morphological basis of the functional reinnervation of Purkinje cells.
Multiple Purkinje Cell Recording in Rodent Cerebellar Cortex
Authors: Sasaki K. , Bower J. M. , Llinás R.
Published: April 2006

The spatial and temporal organization of climbing fibre activation of Purkinje cells, the so‐called complex spikes, were studied in the rat cerebellar Crus II folium utilizing a multiple microeletrode recording technique. As many as 32 Purkinje cells could be simultaneously recorded by using a custom‐built electronic amplifier system and a special data storage device. Analysis of the auto‐correlation activity of complex spikes in any given group of Purkinje cells indicated that activation occurs with a particular rhythmicity having a base firing of 10 Hz. Cross‐correlation of spontaneous complex spikes demonstrated, in addition to a particular rhythmicity, an extraordinarily high degree of synchronicity within a particular spatial distribution of Purkinje cells. Thus, Purkinje cells organized in rostra‐caudal rows tend to fire within 1 ms of each other for distances as far as 800 μm (the width of a folium) from the ‘master’ neuron. By contrast, Purkinje cells located medial or lateral to the master neuron showed almost no cross‐correlation. Administration of harmaline to the animal increased the degree of auto‐ and cross‐correlation but did not change the spatial order of the distribution of the cross‐correlation. The results indicate that the olivo‐cerebellar system is organized in such a way that climbing fibre afferents may be activated in a close‐to‐synchronous and rhythmic fashion. The spatial distribution of these afferents over the cortex is such as to activate rostro‐caudal bands of Purkinje cells which tend to fire in a close‐to‐synchronous manner.
Regional‐ and Age‐Specific Neurochemical Alterations in Rats Rendered Microencephalic by Differentially Timed Gestational Methylazoxymethanol Treatment
Authors: Virgili M. , Barnabei O. , Contestabile A.
Published: April 2006

Rats with different degrees of microencephaly were obtained by injecting pregnant mothers with methylazoxymethanol acetate (MAM) at gestational days 13.5 or 16.5. Specific markers for cholinergic (choline acetyltransferase, ChAT), GABAergic (glutamate decarboxylase, GAD), and glutamatergic (D‐3H aspartate high affinity uptake) neurons, were measured in several brain regions (cortex, hippocampus, anterior and posterior striatum, medial septum plus nucleus of the diagonal band, globus pallidus) in young and adult microencephalic rats. In adult rats born to mothers injected with MAM at gestational day 16.5 (G 16.5) ChAT level was increased in the cortex, hippocampus and striatum but decreased in the septal complex; GAD was decreased in the globus pallidus and, to a little extent, in the hippocampus while D‐3H aspartate uptake was decreased in the striatum. One month old rats belonging to the same group showed comparable differences with the exception of larger increase of ChAT in the cortex and striatum. In adult rats born from mothers injected with MAM at gestational day 13.5 (G13.5) differences in the cholinergic marker were in general less pronounced; GAD was not decreased in the globus pallidus and D‐3H aspartate uptake was unchanged in the striatum but significantly decreased in the hippocampus. The results are correlated with morphological brain alterations caused by differentially timed MAM treatment and with available information on the generation time of various neuronal populations. They show that the balance between different neurotransmitter systems can be experimentally altered and suggest that MAM treatment may provide an experimental tool for studying the development of this balance.
Calibre and Microtubule Content of the Non‐Medullated and Myelinated Domains of Optic Nerve Axons of Rats
Authors: Hernández Carolina , Blackburn Eileen , Alvarez Jaime
Published: April 2006

Calibres and microtubule contents of the non‐medullated and myelinated domains of optic nerve axons of adult rats were studied with the electron microscope. The cross‐sectional areas of the non‐medullated domain was 0.25 μm2, and that of the myelinated domain 0.40 μm2, that is, greater by 59%. The increase in size was uneven across the axonal population; it was marked in fine and medium sized axons, and modest in the largest axons. The number of microtubules increased with axonal size; the density, however, decreased from 85 mirotubules/μm2 axons to about 20 in 1.2 μm2 axons. In axons of equal cross sectional area, the microtubular density of the myelinated and non‐medullated domains was the same. Microtubular density values of optic axons resemble those of dorsal roots more than those of peripheral nerve axons of equal calibre. The facts that optic axons increase in size and gain microtubules behind the eyeball while the microtubular packing decreases suggest a local regulation of the axonal cytoskeleton.
Glycoprotein Synthesis Is Necessary for Memory of Sickness‐Induced Learning in Chicks
Authors: Barber Alistair J. , Gilbert David B. , Rose Steven P. R.
Published: April 2006

Can current biochemical models of memory account for sickness‐induced learning? We show that chicks can form an association between pecking a coloured but tasteless lure and becoming ill (LiCI, i.p.) 30 min later. We go on to demonstrate amnesia for this association, induced by intracranial administration of 2‐deoxygalactose (10 μmole per hemisphere, in a 10 γl vol), an inhibitor of the synthesis of glycoproteins of the synaptic membrane, 10 min before pecking. Further, we show that this 2‐deoxygalactose‐induced amnesia is not state dependent. Thus the brain representation of the lure must be held, and require macromolecular syntheses, similar to those found in other forms of learning, for a considerable time before it can be associated with new significant experience. This is incompatible with contiguous synaptic firing views of memory.
Survival and Axonal Elongation of Adult Rat Retinal Ganglion Cells
Authors: Thanos Solon , Bähr Mathias , Barde Yves‐Alain , Vanselow Jens
Published: April 2006

A peripheral nerve exudate, collected in situ from the proximal end of a severed rat sciatic nerve, can induce substantial axonal elongation from ganglion cells when tested on explanted adult rat retinae. The responsive cells are identified on the basis of their Thy 1.1 immunostaining properties. Similar outgrowth can be obtained from explants when the culture medium is supplemented with brain‐derived neurotrophic factor (BDNF). In addition, both BDNF and the sciatic nerve exudate can prevent ganglion cell degeneration as shown by the retrograde transport of a fluorescent dye that had been applied to the superior colliculus prior to explantation. The results demonstrate that soluble components, released by lesioned peripheral nerves, can effect adult retinal ganglion cells in a way that is reminiscent of that which has been described in vivo using sciatic nerve grafts after sectioning of the optic nerve. The molecular nature of these components is discussed.
Fos‐Like Immunoreactivity Induced by Seizure in Mice Is Specifically Associated With Euchromatin in Neurons
Authors: Mugnaini Enrico , Berrebi Albert S. , Morgan James I. , Curran Tom
Published: April 2006

Administration of convulsant drugs causes the rapid induction of c‐fos in identified neurons within the mouse central nervous system (Morgan et al., 1987). In particular, Fos‐like immunoreactivity is evident in nuclei of granule cells of the hippocampal dentate gyrus within 30 minutes of the onset of seizure. By immunoelectron microscopy, Fos antibody binding was exclusively localized to dispersed chromatin (euchromatin) of several types of projection neurons and local circuit neurons in various brain regions and especially in the dentate gyrus, 210 minutes after a single injection of Metrazol. Fos‐like immunoreactivity was not detectable in the nucleolus, nor in the characteristic peripheral and nucleolus‐associated heterochromatin of hippocampal granule cells. No immunostaining was observed in nuclei of glial, ependymal or endothelial cells, and no cytoplasmic reactivity was seen in any cell type. These findings support a role for Fos in stimulus‐response coupling at the level of transcriptional regulation in neurons.
Physiological and Ultrastructural Characterization of a Central Synaptic Connection between Identified Motor Neurons in the Locust
Authors: Burrows M. , Watson A. H. D. , Brunn D.
Published: April 2006

An excitatory connection between an extensor and several flexor tibiae motor neurons that innervate antagonistic muscles in the hind leg of a locust has been characterized using physiological and ultrastructural methods. Simultaneous intracellular recordings from the single fast extensor (FETi) motor neuron and up to three flexor motor neurons show that a spike in FETi is followed by a short latency depolarizing synaptic potential in the flexors that is powerful enough to evoke a burst of flexor spikes. The chemically mediated excitatory postsynaptic potential (EPSP) is caused centrally as it persists when sensory feedback from the leg is removed, and has a latency of 1.6–2.0 ms depending upon the position of the recording electrodes in the somata or neuropilar segments of the pre‐ and postsynaptic neurons. The amplitude of the EPSP declines gradually in a saline containing no calcium but high magnesium, indicating that no spiking interneuron is interposed in the pathway. With repetitive stimulation, the EPSP decrements markedly so that at intervals of 50 ms the second EPSP of a pair is reduced by 90%. The amplitude of the EPSP is also dependent on the amplitude of the presynaptic spike.

The physiological evidence suggesting a monosynaptic connection is directly confirmed by electron microscopy of ganglia in which FETi and a flexor were both labelled with horseradish peroxidase. Direct chemical synapses between the two identified neurons, in which FETi is the presynaptic element, occur in three regions of the neuropil examined. At a synapse, the flexor motor neuron may be the only postsynaptic neuron or it may be one element in a dyad. The synaptic arrangements between the two neurons are complex with serial synapses through unlabelled processes linking FETi to flexor motor neurons and with frequent reciprocal synaptic connections between FETi and unlabelled processes. Unidentified processes also make input synapses on both neurons close to the synapses from FETi.

The behavioural significance of the connection lies in the mechanical requirements for kicking and jumping. To prepare for these powerful movements the extensor and flexor tibiae muscles must co‐contract. The connection from FETi enhances the depolarization and frequency of spikes in the flexors during the co‐contraction.
Effects of Pertussis Toxin Suggest a Role for G‐Proteins in the Inhibition of Acetylcholine Release from Rat Myenteric Plexus by Opioid and Presynaptic Muscarinic Receptors
Authors: Doležal V. , Tuček S. , Hynie S.
Published: April 2006

Longitudinal muscle preparations of the rat ileum with the attached myenteric plexuses (LMMPs) were preloaded with (3H)choline and the effects of drugs on the depolarization‐evoked release of radioactivity corresponding to (3H) acetylcholine ((3H)ACh) were measured. The release of (3H)ACh was inhibited by morphine and the effect of morphine was blocked by naloxone. Morphine had no effect on the release of (3H)ACh in LMMPs from rats that had been injected with pertussis toxin (PTX) 7 days before experiments.

Carbamoylcholine applied in the presence of tetrodotoxin inhibited the release of (3H)ACh evoked by depolarization of LMMPs. The effect of carbamoylcholine was absent in LMMPs from rats pretreated with PTX.

The effects of PTX indicate that one or more PTX‐sensitive G proteins are involved in the chain of events mediating the action of opioid and muscarinic receptors on the release of ACh from the myenteric plexus. It is suggested that the inhibition of ACh release depends on G‐protein‐mediated coupling of opiod receptors with K+ channels and of muscarinic receptors with Ca2+ channels, but alternative explanations cannot be excluded.
Cholecystokinin: Corelease with dopamine from nigrostriatal neurons in the cat
Authors: Artaud F. , Baruch P. , Stutzmann J. M. , Saffroy M. , Godeheu G. , Barbeito L. , Hervé D. , Studler J. M. , Glowinski J. , Chéramy A.
Published: April 2006

Halothane‐anaesthetized cats were implanted with push‐pull cannulae to demonstrate the in vivo release of cholecystokinin‐like immunoreactivity (CCK‐LI) in the substantia nigra and the ipsilateral caudate nucleus. The spontaneous and the calcium‐dependent potassium‐evoked release of CCK‐LI were observed in both structures. In addition, the local application of tetrodotoxin (10−6 M) reduced the spontaneous release of the peptide. 6‐OHDA lesions made in the substantia nigra pars compacta led to a complete destruction of nigrostriatal dopaminergic neurons. CCK‐LI levels were not affected in the caudate nucleus but were reduced substantially in the substantia nigra. The activation of dopaminergic cells induced by the nigral application of alpha‐methyl‐para‐tyrosine (10−4 M) stimulated the release of CCK‐LI and dopamine in the ipsilateral caudate nucleus, whilst opposite effects were seen in the substantia nigra. Similar results were obtained when dopaminergic transmission was blocked in the caudate nucleus suggesting that the evoked release of CCK‐LI by the alpha‐methyl‐para‐tyrosine treatment originates from dopaminergic nerve terminals and not from other CCK‐LI containing fibres in response to released dopamine. Dopamine (10−7 M) as well as the D1 agonist SKF 38393 (10−5 M) stimulated CCK‐LI release when applied into the caudate nucleus while the D2 agonist, LY 171555 (10−6 M) slightly reduced peptide release. The local application of cholecystokinin‐8 sulfate (CCK‐8S) (10−8 M, for 30 min) into the substantia nigra pars compacta increased the firing rate of dopaminergic cells and stimulated the release of newly synthesized 3H‐dopamine from dendrites and nerve terminals.

These results suggest, but do not definitively prove, that, in the cat, CCK‐LI and dopamine are coreleased from nigrostriatal mixed dopaminergic/CCK‐LI neurons and that CCK‐LI released from dendrites is, like dopamine, involved in the regulation of the activity of these cells.
Non‐Competitive Antagonism of N‐Methyl‐D‐Aspartate by Displacement of an Endogenous Glycine‐Like Substance
Authors: Fletcher E. J. , Millar J. D. , Zeman S. , Lodge D.
Published: April 2006

N‐methyl‐D‐aspartate (NMDA; 40 μM) induced depolarizations of cortical wedges that were reduced by 30–60% in the presence of D‐2‐amino‐5‐phosphonovalerate (D‐AP5; 5 μM), ketamine (5 μM), dextrorphan (5 μM), magnesium (500 μM), kynurenate (200 μM), and 1‐hydroxy‐3‐aminopyrrolidone‐2 (HA‐966; 200 μM). Superfusion with glycine (1 μM‐1 mM) did not enhance the action of NMDA in control medium and in media containing D‐AP5, ketamine, dextrorphan, or magnesium. In the presence of kynurenate and HA‐966, however, NMDA‐induced depolarizations were enhanced in a dose‐dependent manner by glycine (10 μM‐3.16 mM). NMDA antagonism produced by HA‐966 appeared to be more completely reversed than that produced by kynurenate. This action of glycine was mimicked by D‐serine but not by GABA or L‐serine, and was resistant to strychnine (10–50 μM). Reduction of responses to quisqualate by kynurenate was not reversed by glycine.

In these cortical wedges, spontaneous synaptic activity was observed in nominally magnesium‐free medium and this epileptiform activity could be blocked by the above NMDA antagonists. Glycine and D‐serine reversed only the effects of kynurenate and HA‐966 on such synaptic activity.

These results suggest there is an endogenous glycine‐like compound acting on NMDA receptor‐ionophore complexes and that displacement of this compound by HA‐966 or kynurenate produces antagonism of NMDA.
NGF Amplifies Expression of NGF Receptor Messenger RNA in Forebrain Cholinergic Neurons of Rats
Authors: Cavicchioli L. , Flanigan T. P. , Vantini G. , Fusco M. , Polato P. , Toffano G. , Walsh F. S. , Leon A.
Published: April 2006

In order to study the ligand‐mediated regulation of NGF receptors in vivo, we assessed NGF receptor mRNA in the septal area of both neonatal and adult rats following intraventricular NGF administration. In neonatal rats NGF treatment, in comparison with cytochrome c, elicited a pronounced augmentation in the level of NGF receptor mRNA. A similar effect was also observed following continuous intraventricular NGF infusion in young adult rats. In addition, in this latter case, the increase in NGF receptor mRNA was associated with an increase in NGF receptor‐related immunoreactivity, most likely associated with the cholinergic neurons, in the septal area. These results show that NGF itself may regulate expression of NGF receptor mRNA and corresponding protein levels in forebrain cholinergic neurons and suggest that NGF effects in the CNS may be mediated by an up‐regulation of NGF receptors.
Immunoreactive Calcitonin Gene‐Related Peptide, Vasoactive Intestinal Polypeptide, and Somatostatin in Developing Chicken Spinal Cord Motoneurons
Authors: Villar Marcelo J. , Roa Michèle , Huchet Monique , Hökfelt Tomas , Changeux Jean‐Pierre , Fahrenkrug Jan , Brown John C. , Epstein Miles , Hersh Louis
Published: April 2006

The distribution of calcitonin gene‐related peptide (CGRP)‐, vasoactive intestinal polypeptide (VIP)‐, and somatostatin (SOM)‐like immunoreactivities (‐LI) in neurons of the spinal cord of developing chickens was characterized by use of the indirect immunofluorescence technique, and the findings related to a possible role for these peptides in the development of muscles and motor endplates.

CGRP‐LI in presumptive motoneurons of the ventral horn was first observed at embryonic day 6. During the following days the number of CGRP‐immunoreactive (IR) cells increased reaching high numbers between days 12 and 18 of incubation, and thereafter decreasing in numbers until hatching. SOM‐LI was first observed on embryonic day 7, while VIP‐LI appeared on days 12–13. The number of SOM‐ and VIP‐IR cells was considerably lower than that observed for CGRP‐LI, but they also exhibited an initial increase followed by a decrease towards hatching. Intrathecal administration of colchicine increased the number of CGRP‐IR motoneurons at days 7 and 30 after hatching and of VIP‐IR ones at day 7, while at day 30 no expression of VIP‐LI was found. Colchicine treatment did not cause any significant change in the number of SOM‐IR motoneurons after hatching.

The effect of VIP, SOM, and CGRP on cAMP accumulation in primary cultures of chick muscle cells was determined after labelling of the cells by (2‐3H) adenine and by radioimmunoassay. All three peptides stimulated the accumulation of cAMP. However, the development of the pharmacological response of each of the peptides followed a different time course during in vitro differentiation of the primary cultures. The response of CGRP was the latest to develop and did not significantly decrease after the maximal response had been reached around day 3.

The data are discussed in terms of ‘trophic’ effects of these neuropeptides upon muscle and spinal cord differentiation and synaptogenesis.
Behaviour of Medial Rectus Motoneurons in the Alert Cat
Authors: de la Cruz R. R. , Escudero M. , Delgado‐Garcia J. M.
Published: April 2006

The activity of identified medial rectus motoneurons was recorded in alert cats during spontaneous and vestibular induced eye movements. Medial rectus motoneurons fired a burst of spikes slightly preceding adducting saccades and increased their discharge rate linearly with successive eye positions in the adducting direction. Conduction velocity (21.3–98.2 m/s), eye position sensitivity (ks, 7.1 ± 1.5 spikes/s°deg), and eye velocity sensitivity (rs, 1 ± 0.2 spikes/s°deg/s) during spontaneous eye movements, and time constants calculated from phase lead analysis (T0, 135 ± 36 ms) showed values similar to those described previously for cat abducens motoneurons. The firing rate during repeated fixation of the same eye position was affected significantly by the direction of the preceding saccade and by the animal's level of alertness. Eye velocity sensitivity was not significantly affected by changes in the animal's level of alertness. A weak negative relationship (coefficient of correlation = ‐0.56) was observed between eye velocity sensitivity (rv) and sinusoidal rotational frequency, with no change in eye position sensitivity (kv) with stimulus frequency. The subsequent changes in the time constant (Tv) calculated as Tv= rv/kv in relation to stimulus frequency suggests that the oculomotor system deviates from a (linear) first‐order model.
Immunocytochemical Localization of Glia‐Derived Nexin, Laminin and Fibronectin on the Surface or Extracellular Matrix of C6 Rat Glioma Cells, Astrocytes and Fibroblasts
Authors: Halfter W. , Reinhard E. , Liverani D. , Ortman R. , Monard D.
Published: April 2006

The expression and cellular distribution of glia‐derived nexin (GDN), laminin and fibronectin on C6 rat glioma cells, rat brain astrocytes and rat fibroblasts were investigated by immunoblotting and immunocytochemistry. Western blot analysis of C6 cell homogenates confirmed the specificities of the antibodies. Immunocytochemical staining of C6 cells, astrocytes and fibroblasts showed that laminin, fibronectin and GDN were abundant on the surface of glioma cells and astrocytes whereas on fibroblasts fibronectin was abundant though only traces of GDN and laminin could be detected. The light microscopy data were confirmed by ultrastructural studies showing that each antigen was present on the surface of the C6 rat glioma cells as numerous spots with slightly different distribution patterns for each of the antigens. In fibroblast cultures, the antigens were also localized in the extracellular matrix in the vicinity of the cells. Migrating fibroblasts but not migrating glioma cells or astrocytes deposit the matrix‐proteins onto the substratum leaving behind a track of GDN, laminin and fibronectin. When the cells were treated with heparin prior to antibody incubation, the GDN immunoreactivity completely disappeared, whereas the distribution and abundance of laminin and fibronectin was not affected. Our data show that GDN binds, possibly by a heparin‐like molecule, to the outer surface of cells or to the extracellular matrix and may protect cells and matrix proteins against proteolytic degradation.
The Drosophila Mutant tetanic Interacts with a Gene Complex Including the Structural Locus of K+ Channels and Shows Altered Dephosphorylation and Learning
Authors: Orgad S. , Llamazares S. , Dudai Y. , Ferrús A.
Published: April 2006

The tetanic (tta; X.‐52.6) mutation has been isolated on the basis of its sensitivity to extradoses of the normal Shaker gene complex (ShC) where the K+ channel la is encoded. The mutant shows up to threefold elevation of the membrane bound protein phosphatase type 1 (PP1) activity in body extracts, probably due to reduced levels of the PP1 specific inhibitor 2 (I‐2). By contrast, PP1 activity in the head is only half of the normal value. In addition, tta fails to perform normally in a negative reinforcement olfactory paradigm. The functional relationships between phosphorylation, K+ currents, phosphatase activity and modulation of synaptic activity during learning and memory are discussed in the light of their possible genetic links.
Differential Expression of bcl‐2 and bax mRNA in Axotomized Dorsal Root Ganglia of Young and Adult Rats
Authors: Gillardon Frank , Wickert Hannes , Zimmermann Manfred
Published: April 2006

Bcl‐2 and Bax have recently been identified as putative repressor and effector proteins respectively, in the cell death program of growth factor‐deprived haematopoietic cell lines. Overexpression of bcl‐2 in neuronal cell culture prevents apoptosis induced by removal of neurotrophic factors. In the present in vivo study the expression of bcl‐2 and bax mRNA has been investigated in dorsal root ganglia of young and adult rats using polymerase chain reaction. A high constitutive expression was observed for both genes in control ganglia. Unilateral transection of the sciatic nerve led to a dramatic decrease in bcl‐2 mRNA levels in ganglia of young animals within 5 days following nerve lesion and a partial recovery thereafter. In contrast, the decline in bcl‐2 mRNA was much less pronounced in axotomized ganglia of adults. The amount of bax transcripts did not change significantly in ganglia of both young and adult rats up to 20 days after nerve injury. The decrease in bcl‐2 expression in dorsal root ganglia may be part of the molecular mechanism leading to neuronal cell death after axotomy‐induced deprivation of neurotrophic factors. The age‐dependent decline in the ratio of bcl‐2 to bax gene products may explain the greater susceptibility of immature neurons to apoptosis.
A randomized study comparing an antireflux system with a direct ureteric anastomosis in patients with orthotopic ileal neobladders
Authors: SHAABAN ATALLAH A. , ABDEL‐LATIF MOHAMED , MOSBAH AHMED , GAD HOSSAM , ERAKY IBRAHIM , ALI‐EL‐DEIN BEDEIR , OSMAN YASSER , EL‐MEKRESH MOHSEN , IBRAHIM EL‐HOUSSEINY , EL‐KAPPANY HAMDY
Published: April 2006

Authors from Egypt conducted a randomized prospective study into the benefit of an anti‐reflux system in patients with orthotopic ileal neobladders. They found that anti‐reflux procedures were associated with a higher incidence of anastomotic structures. An editorial comment accompanies this paper, and together the two manuscripts make for interesting reading.

OBJECTIVE

To assess the benefit of an antireflux system in patients with orthotopic ileal neobladders, as there is controversy about whether reflux prevention offers any advantages.

PATIENTS AND METHODS

We conducted a randomized prospective study between January 2002 and March 2004, on 60 patients (53 men and seven women) with a mean (sd) age of 52.7 (7.3) years, who were candidates for orthotopic neobladders. Patients with comorbidities were excluded. Preoperative evaluation included intravenous urography (IVU), cystoscopic biopsy and radioisotope renography to evaluate the differential glomerular filtration rates (GFRs). Cases with normal kidneys and ureters, and with similar GFRs, were enrolled. Surgery comprised a standard radical cystectomy with pelvic lymphadenectomy. The ureters were randomized to either a direct anastomosis into a 5‐cm ileal chimney on one side, or to be implanted using the antireflux serous‐lined extramural tunnel on the contralateral side in the same patient. Regular follow‐up included IVU and renography every 6 months in cancer‐free patients.

RESULTS

The mean (sd) follow‐up was 23 (9.6) months. There was prolonged urinary leak from a refluxing ureter in one patient that was treated with a temporary percutaneous nephrostomy. Symptomatic pelvic collections required tube drainage in six cases. Six ureters developed early anastomotic strictures (one direct and five antirefluxing), and were treated with endoscopic ureterotomy in three and open revision in three. Serum creatinine levels were normal in all patients throughout the observation period. GFRs were similar in the two groups. The mean GFRs before surgery and at 6, 12, 18, and 24 months after cystectomy were: 55.1, 50.7, 49.4, 52.2 and 53.9 mL/min for the direct side; and 56.1, 53, 52.4, 53.2 and 50.4 mL/min for renal units with antirefluxing implantation. There was a significant deterioration of the GFRs due to anastomotic strictures, from 48.6 (6.7) mL/min before surgery to 31.8 (15.9) mL/min after the revision (P = 0.01).

CONCLUSIONS

The antireflux procedures were associated with a higher incidence of anastomotic strictures than the direct methods and there was a significant deterioration of renal function after obstruction. The long‐term follow‐up data are awaited.
The effects of human chorionic gonadotrophin on normal testicular tissue of rats: dose‐dependence and reversibility
Authors: KARAMAN IHSAN M. , KAYA CEVDET , OZTURK METIN , PIRINCCI NECIP , YIMAZGUMRUKCU GULISTAN , TUKEN MURAT
Published: April 2006

OBJECTIVE

To investigate the effect of human chorionic gonadotrophin (hCG) on rat testicular tissue, and its reversibility and dose dependence.

MATERIALS AND METHODS

Male Wistar rats were assigned to groups (10 rats/group) receiving 10, 30 or 50 IU/kg hCG subcutaneously once daily for 15 days; 10 controls received subcutaneous isotonic saline. At 1 and 3 months later, five rats in each group were killed and their testes removed. The testes were examined histologically to measure seminiferous tubular diameter and germinal membrane thickness.

RESULTS

At 1 month after hCG administration, the mean germinal membrane thickness in the testicular tissues of the hCG‐treated rats was significantly less than in control rats, and was also significantly different between all of the hCG‐treated groups (P < 0.05). However, at 3 months after hCG administration, all histological variables were similar to those in control rats (P > 0.05), and the mean germinal membrane thickness at 3 months after hCG administration was larger than that at 1 month (P < 0.05). There were no significant differences in the mean seminiferous tubular diameter between hCG‐treated rats and control rats.

CONCLUSION

hCG impairs seminiferous tubule histology in the ‘normal’ descended testes of rats. This effect was dose‐dependent, and the changes were reversed at 3 months after treatment. Thus, although hCG therapy might affect the seminiferous tubules of contralateral descended testes in cryptorchid boys, these effects might be reversible.
Infant Predictors of Inhibited and Uninhibited Profiles
Authors: Kagan Jerome , Snidman Nancy
Published: April 2006

Previous research on subjects showing the two temperamental profiles called inhibited and uninhibited to unfamiliar events suggests that the two groups differ in threshold of reactivity to novelty. Hence, variation among infants in behavioral reactivity to unfamiliar events might predict later display of the two profiles. In a longitudinal study of 94 four-month-old infants, those who displayed the combination of high motor activity and frequent crying to stimulation were more fearful to unfamiliar events at nine and 14 months than infants who displayed both low motor activity and infrequent crying. This result implies that the processes that mediate early reactivity to stimulation may also influence a later preparedness to avoid or to approach unfamiliarity.
The Technological Perspective
Authors: Kipnis David
Published: April 2006

Changes in technology after the ability of people to express competence, to interact with others, to be active rather than passive, and to exercise influence. For the most part, these changes in psychological processes are accidental by-products of technology's attempts to solve the practical problems of society. Because of the close relation between technology and social behavior, we argue that technology should be included as an explanatory variable in social psychology's construction of behavior. Several benefits should result from developing a social psychology of technology. For one, social psychology will be better able to account for the variance of critical social behaviors such as competence, autonomy, social influence, and social isolation. Second, the study of technology will provide a historical perspective for examining changes in social behavior. Finally, the application of social psychological constructs and methods to the study of technology will provide insights that are not available from studies of this topic by economics, philosophy, and political science.
Attention and Feature Integration: Illusory Conjunctions in a Patient with a Parietal Lobe Lesion
Authors: Cohen Asher , Rafal Robert D.
Published: April 2006

This article explores the relation between spatial attention and feature integration in a parietal patient. When the patient had to focus her attention in the middle of the visual field by performing a digit task, she committed a much larger number of illusory conjunctions on the side contralateral to her lesion than on the side ipsilateral to her lesion. When the digit task was eliminated, thereby relaxing the requirement of focused attention, the number of illusory conjunctions on the contralateral side was dramatically reduced. These results indicate that the spatial attention mechanism plays a central role in feature integration.
Behavioral Tests of a Prediction from a Cortical Network Simulation
Authors: Granger Richard , Staubli Ursula , Powers Hollie A. , Otto Tim , Ambros-Ingerson José , Lynch Gary
Published: April 2006

Behavioral predictions arising from a simulation of olfactory paleocortex were examined using rats in an olfactory discrimination-learning task. The animals were tested to see whether, as predicted, they would recognize novel similar odors as members of a category, and whether they would nonetheless distinguish and recognize individual category members. The results were positive, providing the first evidence that rats learn perceptual clusters via unsupervised learning.
When's a Smile a Smile? Or how to Detect a Message by Digitizing the Signal
Authors: Leonard Christiana M. , Voeller Kytja K.S. , Kuldau John M.
Published: April 2006

What's in a smile? Why do we respond so powerfully to this visual display? Or, phrased in information processing terms: What characteristics of the signal define the boundaries of the social message? We have used digital image analysis and subject ratings to answer this question for videotaped smiles. A simple measure of the information provided by facial movement—the entropy of the distribution of pixel intensities in the subtracted or difference images—traced the changing facial expression (the signal) through time. Raters categorized the individual videoprints in order to locate message boundaries. We found a remarkable coincidence between changes in signal entropy and message. In each smile, rapid increases in positive messages occurred within entropy crests. We conclude that quantitative measures of information transmission can be used to locate message boundaries and provide insight into how receivers parse the behavioral stream.
An Attitude Survey of Animal Rights Activists
Authors: Plous S.
Published: April 2006

Animal rights activism is increasing rapidly, yet no empirical research has sought to determine who the animal rights activists are, what they believe, and what they hold as their agenda. An attitude survey was therefore conducted of 402 animal rights activists who attended a recent rally in Washington. Results indicated that nearly half of these activists felt that animal research should not be the primary focus of the animal rights movement. There was also considerable disagreement surrounding the issue of laboratory break-ins. These and other findings from the survey suggest that animal rights activists hold diverse objectives and viewpoints.
The Effects of Aging and First Grade Schooling on the Development of Phonological Awareness
Authors: Bentin Shlomo , Hammer Ronen , Cahan Sorel
Published: April 2006

The independent influences of aging and schooling on the development of phonological awareness were assessed using a between-grades quasiexperimental design. Both schooling (first grade) and aging (5–7 years) significantly improved children's performance on tests of phonemic segmentation, but the schooling effect was four times larger than the aging effect. The schooling effect was attributed to formal reading instruction, whereas the aging effect probably reflects natural maturation and informal exposure to written language. These data support a strong mutual relation between reading acquisition and phonological awareness.
Networks and Theories: The Place of Connectionism in Cognitive Science
Authors: McCloskey Michael
Published: April 2006

This article considers how connectionist modeling can contribute to understanding of human cognition. J argue that connectionist networks should not be thought of as theories or simulations of theories, but may nevertheless contribute to the development of theories.
A Semantic Space of Color Names
Authors: Izmailov Ch.A. , Sokolov E.N.
Published: April 2006

Three Russian subjects learned arbitrary pairings between 20 colors and 20 three-letter artificial color names. After different amounts of this training, the subjects rated the difference between the colors associated with every pair of artificial names when these names were presented without the colors. Multidimensional scaling of the ratings after a small amount of training revealed a grouping of the words into four semantic clusters corresponding to the following groups of related colors: the violets, the blues, the greens, and the yellows-through-reds. After more extensive training, multidimensional scaling yielded the full color circle of hues. Further analysis of the data indicated that a spherical model previously proposed by the authors for sensory color space has advantages, also, for the semantic color space obtained when only the names of colors are presented. The results are interpreted in terms of a two-stage process of neuronal analysis of visual inputs in which the activity of four color-opponent channels is followed by differential activation of cells tuned to specific colors.
Inelastic Preference for Ethanol in Rats: An Analysis of Ethanol's Reinforcing Effects
Authors: Heyman Gene M. , Oldfather Chad M.
Published: April 2006

This experiment evaluated the relationship between availability of ethanol and preference for ethanol in rats. One dipper served a mixture of 10% ethanol and 10% sucrose, and a second dipper served 10% sucrose. In the first condition, access to each dipper was governed by a variable-interval 5-s schedule. In subsequent conditions, the interval requirement for the ethanol mixture was increased to 30 s. However, increases in the interval requirement did not decrease preference for ethanol. Instead, preference increased somewhat or remained about the same. In contrast, when both dippers served sucrose, increases in the interval requirement at one dipper systematically shifted preference to the other dipper. Analysis showed that preference for ethanol was correlated with amount of ethanol consumed, whereas preference for sucrose was correlated with changes in the reinforcement contingencies. Ethanol's food value, as measured by calories, did not predict preference. Rather, the results were most simply explained by the theory that ethanol's pharmacological consequences maintained responding.
Choosing to Vary and Repeat
Authors: Neuringer Allen
Published: April 2006

Can animals choose to vary their behaviors or to repeat them, depending on the rewards they earn for behaving variably versus repetitively? To answer this question, pigeons were rewarded for four-response sequences made to left (L) and right (R) disks. A “varied” sequence differed from each of the previous three sequences, and a “repeated” sequence was the same as some one of the previous three. For example, if a pigeon had generated sequences LLLL. LLLR, and LLRR in that order, then an RRRR sequence in the next trial was defined as a variation, whereas LLLL was a repetition. Two experiments showed that frequencies of varied and repeated sequences depended on the frequencies with which they were reinforced, with a “matching” relationship accounting for the results. It was concluded that pigeons' choices to vary or repeat parallel their choices between simpler response alternatives, a result consistent with the hypothesis that behavioral variability is influenced by its consequences. This finding may help to explain the “voluntary” or “free” nature of operant behavior.
Unobservable Facial Actions and Emotion
Authors: Tassinary Louis G. , Cacioppo John T.
Published: April 2006

Surface electromyographic recordings in humans were first made less than 70 years ago, and the electromyographic study of covert facial actions during affect and emotion has less than a 20-year history. Despite the relative youth of facial electromyography, its use in combination with autonomic measures and comprehensive overt facial action coding systems has provided a sensitive and effective armamentarium for investigating emotion and affect-laden information processing. Research over the past decade has demonstrated that facial electromyographic activity varies as a function of the intensity, valence, and sociality of emotional stimuli and shows that facial electromyographic activity is slightly different in deliberately manipulated and spontaneous expressions of emotion. The multiply determined nature of facial actions and expressions, however, has limited the inferences that can be made about the psychological significance of facial electromyographic responses. These limitations have begun to recede in recent years as a result of advances in the psychometric properties of facial electromyographic measurements, the quantification of electromyographic waveforms and patterns, the conjoint measurement of facial electromyographic and electro-cortical activity, the conceptualization of psychophysiological relations, and the formalization of psychophysiological inference.
Facial Expressions of Emotion: New Findings, New Questions
Authors: Ekman Paul
Published: April 2006

The evidence on universals in facial expression of emotion, renewed controversy about that evidence, and new findings on cultural differences are reviewed. New findings on the capability for voluntarily made facial expressions to generate changes in both autonomic and central nervous system activity are discussed, and possible mechanisms by which this could occur are outlined. Finally, new work which has identified how to distinguish the smile of enjoyment from other types of smiling is described.
Behavior-Genetic Strategies in the Study of Emotion
Authors: Gabbay Frances H.
Published: April 2006

Behavior-genetic studies of emotionality in rats and human studies of adult personality and childhood temperament provide evidence of genetic effects on emotion-relevant trails. Twin studies of autonomic reactivity suggest that psychophysiologic responses to stress are heritable. Genetic analyses of fears reveal that the magnitude of genetic influence varies across fears and across development. Finally, recent findings in psychiatric genetics shed light on the role of heritable variation in emotional functioning in major psychiatric disorders. Thus, there is evidence from a variety of sources that characteristics relevant to emotion are influenced by genetic factors. However, behavior-genetic methods generally have not been applied in laboratory-based studies of the psychophysiologic, cognitive, or expressive correlates of emotion. Because recent developments in quantitative genetics permit us to go beyond the simple estimation of heritability, a broader application of behavior-genetic strategies to the study of emotion, one which incorporates elicitation of emotion in the laboratory, promises to elucidate the interrelationships among the components of emotional systems.
The Disjunction Effect in Choice under Uncertainty
Authors: Tversky Amos , Shafir Eldar
Published: April 2006

One of the basic axioms of the rational theory of decision under uncertainty is Savage's (1954) sure-thing principle (STP) It states that if prospect x is preferred to y knowing that Event A occurred, and if x is preferred to y knowing that A did not occur, then x should be preferred to y even when it is not known whether A occurred We present examples in which the decision maker has good reasons for accepting x if A occurs, and different reasons for accepting x if A does not occur Not knowing whether or not A occurs, however, the decision maker may lack a clear reason for accepting x and may opt for another option We suggest that, in the presence of uncertainty, people are often reluctant to think through the implications of each outcome and, as a result, may violate STP This interpretation is supported by the observation that STP is satisfied when people are made aware of their preferences given each outcome
Violations of Monotonicity and Contextual Effects in Choice-Based Certainty Equivalents
Authors: Birnbaum Michael H
Published: April 2006

This article investigates choices between gambles and amounts of money to explore two issues in decision making First, in recent studies, judgments of the values of gambles violated monotonicity (dominance), yet choices between the same gambles satisfied monotonicity, producing reversals of preference This experiment tested whether certainty equivalents based on choices between gambles and money would violate monotonicity Results indicated that these choices violated monotonicity in the same way as had Judgments Second, this experiment investigated whether the certainty equivalent of a gamble would depend on the distribution of amounts offered for comparison It was found that certainty equivalents based on choices depended on the context in the same fashion as psychophysical comparisons Apparently, paradoxes of behavioral decision making are not eliminated by using choices instead of judgments to investigate human preferences