bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of thickness and appearance of anterior talofibular and calcaneofibular ligaments in normal versus abnormal ankles with MRI
Authors: Dimmick S , Kennedy D , Daunt N 
Published: January 2009

SummaryInjuries to the lateral ligaments of the ankle are common in medical practice. The most commonly injured ligaments are the anterior talofibular (ATFL) and calcaneofibular (CFL) ligaments. When undertaking MRI evaluation of ankle injuries it is important to understand the normal dimensions, appearance and variations of these ligaments. Twenty‐eight consecutive patients referred for MRI of the ankle underwent bilateral scanning. The thickness of normal and abnormal ATFL and CFL was determined. The mean thickness of the ATFL was 2.19 ± 0.6 mm and the CFL measured 2.13 ± 0.5 mm. One normal ankle had an extremely thin ATFL (0.8 mm) with an otherwise normal appearance, whereas two ankles had an ATFL with a high attachment, both of which were deemed to be normal variants. Nineteen per cent of normal CFLs were noted to consist of a lateral hypointense band with a medial isointense medial band. Two variations of normal ATFL, one normal variant CFL and a measurement of the normal thickness of the ATFL and CFL have been presented in this paper. These variations have not been described previously by other authors. It is envisaged that these findings will assist in the MRI assessment of the lateral ankle ligaments.
18F‐fluorodeoxyglucose positron emission tomography imaging in brain tumours: The Western Australia positron emission tomography/cyclotron service experience
Authors: McCarthy M , Yuan JB , Campbell A , Lenzo NP , Butler‐Henderson K 
Published: January 2009

Summary 18F‐fluorodeoxyglucose positron emission tomography (FDG‐PET) scans in the first 49 patients referred with either possible brain tumour or brain tumour recurrence were reviewed. FDG‐PET imaging was reported with reference to anatomical imaging. Based on the report the FDG study was classified as either positive or negative for the presence of tumour. Thirty‐eight cases were included in the analysis, 21 having pathological data and 17 with diagnostic clinical follow up. Eleven were excluded, as they had inadequate follow‐up data. Of the 21 cases with pathology, 18 were shown to have tumour. In this group there were five false‐negative scans and two false‐positive PET scans. Seventeen cases were assessed by clinical follow up, nine were considered to have been tumour. There were two false negatives with one false positive. The overall sensitivity, specificity and positive and negative predictive values were 74, 73, 87 and 53% respectively. This is similar to figures previously quoted in published work. Despite relatively limited numbers, the utility of FDG PET imaging in our hands is similar to published reports. With a positive predictive value of 87%, a positive FDG study indicates a high likelihood that there is brain tumour present. A negative study does not exclude the presence of tumour.
Percutaneous antegrade ureteric stent removal using a rigid alligator forceps
Authors: Given MF , Geoghegan T , Lyon SM , McGrath F , Lee MJ 
Published: January 2009

SummaryTo evaluate the safety and efficacy of percutaneous antegrade ureteric stent removal using a rigid alligator forceps. Twenty patients were included in our study. Indications for ureteric stent insertion included stone disease (n = 7), malignancy (n = 8) and transplant anastomotic strictures (n = 5). Stent retrieval was carried out for proximal stent placement/migration in seven patients and encrustation in the remaining 13. Twenty‐two stents were successfully retrieved in 20 patients. There was one technical failure (5%). There were no major complications. We had four minor complications, which included nephrostomy site pain (n = 2), periprocedural sepsis (n = 1) and a small urinoma (n = 1). All patients settled with conservative management. Percutaneous radiologically guided antegrade ureteric stent removal with an alligator forceps is safe and effective, particularly when initial surgical removal has failed.
Survey of the learning activities of Australasian radiation oncology specialist trainees
Authors: Holt T , Bydder S , Bloomfield L 
Published: January 2009

SummaryTrainee radiation oncologists must master a substantial body of skills and knowledge to become competent specialists. The resources available to support this are limited. We surveyed the 90 registrars enrolled in the Royal Australian and New Zealand College of Surgeons (RANZCR) radiation oncology training programme to obtain a range of information about their learning activities (with a significant focus on part 1 teaching). Responses were received from 59 registrars (66% of those eligible). Trainees reported spending a median 2.5 h per week (range 0–10 h) in formal teaching activities. With regard to part 1 exam preparation, 83% reported having had physics teaching – the median quality was 5/7; 88% had radiobiology teaching – the median quality was 4/7; 52% had anatomy teaching – the median quality was 3/7. Registrars training within the RANZCR radiation oncologists training programme perceive their own clinical learning environment as generally good; however’ 50% of respondents felt that more teaching was needed for part 1 subjects. This compared with only 19% of respondents who felt that more teaching was required for part 2 exam preparation. Innovative solutions, such as centralized web‐based teaching, may help to address weaknesses in part 1 teaching. With increasing demands on radiation oncologists and trainees it will be important to monitor learning environments.
Hyperosmolar coma due to exclusive glucose accumulation: Recognition and computations
Authors: BARTOLI ETTORE , SAINAGHI PIER PAOLO , BERGAMASCO LUCA , CASTELLO LUIGI 
Published: January 2009

SUMMARYAim:  To avoid electrolyte derangements during correction of hyperosmolar coma (HC), PNaPREDICTED at the end of correction is presently estimated from plasma glucose (PG, mM/L). When the rise in plasma osmolality (Posm) is entirely due to glucose addition (GA, mM) to the extracellular volume (ECV), this PNa prediction can be improved by correctly estimating GA and any associated water loss (ΔV), while excluding any concomitant Na loss (ΔNa).Methods:  Indicating with 0 the normal conditions, with 1 the HC, establishes an exclusive GA accumulation. We derived the equations for computing GA, ΔV and PNaPREDICTED. Computer simulations of HC were performed by adding the known GA while subtracting the known ΔV and ΔNa in different combinations, obtaining exact values of PNa1 and . Applying our formulas, we recognized and discarded all cases with concomitant ΔNa, and we computed GA, ΔV and PNaPREDICTED from PNa1 and , as if they had been measured in patients. We extended these same calculation algorithms to 68 patients with HC.Results:  In computer simulations, true and calculated GA, ΔV and PNaPREDICTED were identical, such that regression and correlation coefficients were 1 (P < 0.0001). Out of the 68 patients recruited, 13 fulfilled the boundary conditions of an exclusive GA addition. The true values, obtained by balance studies performed on these patients, were not different from and significantly correlated with the calculated data (R2 = 0.99, P < 0.001).Conclusion:  Our new model system for HC and the new formulas improve to near exactness the accuracy in estimating PNaPREDICTED, helping the physician to avoid unwanted electrolyte derangements during treatment.
Double dissociation of the effects of selective nucleus accumbens core and shell lesions on impulsive‐choice behaviour and salience learning in rats
Authors: Pothuizen Helen H. J. , Jongen‐Rêlo Ana L. , Feldon Joram , Yee Benjamin K. 
Published: January 2009

AbstractThe nucleus accumbens can be subdivided into at least two anatomically distinct subregions: a dorsolateral ‘core’ and a ventromedial ‘shell’, and this distinction may extend to a functional dissociation. Here, we contrasted the effects of selective excitotoxic core and medial shell lesions on impulsive‐choice behaviour using a delayed reward choice paradigm and a differential reward for low rates of responding (DRL) test, against a form of salience learning known as latent inhibition (LI). Core lesions led to enhanced impulsive choices as evidenced by a more pronounced shift from choosing a continuously reinforced lever to a partially reinforced lever, when a delay between lever press and reward delivery was imposed selectively on the former. The core lesions also impaired performance on a DRL task that required withholding the response for a fixed period of time in order to earn a reward. Medial shell lesions had no effect on these two tasks, but abolished the LI effect, as revealed by the failure of stimulus pre‐exposure to retard subsequent conditioning to that stimulus in an active avoidance procedure in the lesioned animals. As expected, selective core lesions spared LI. The double dissociations demonstrated here support a functional segregation between nucleus accumbens core and shell, and add weight to the hypothesis that the core, but not the shell, subregion of the nucleus accumbens is preferentially involved in the control of choice behaviour under delayed reinforcement conditions and in the inhibitory control of goal‐directed behaviour.
Electrical coupling induces bistability of rhythms in networks of inhibitory spiking neurons
Authors: Bem Tiaza , Le Feuvre Yves , Rinzel John , Meyrand Pierre 
Published: January 2009

AbstractInformation processing in higher brain structures is thought to rely on the synchronization of spiking neurons. Increasing evidence indicates that, within these structures, inhibitory neurons are linked by both chemical and electrical synapses. However, how synchronized states may emerge from such circuits is not fully understood. Using snail neurons interconnected through a dynamic‐clamp system, we show that networks of spiking neurons linked by both reciprocal inhibition and electrical coupling can express two coexisting coordination patterns of different rhythms. One of these patterns consists of antiphase firing of the network partners whereas, in the other, neurons fire synchronously. Switching between patterns may be evoked immediately by transient stimuli, demonstrating bistability of the network. Thus electrical coupling can provide a potent way for instantaneous reconfiguration of activity patterns in inhibitory spiking networks without alteration of intrinsic network properties by modulatory processes.
Ventral pallidal neurons code incentive motivation: amplification by mesolimbic sensitization and amphetamine
Authors: Tindell Amy J. , Berridge Kent C. , Zhang Jun , Peciña Susana , Aldridge J. Wayne 
Published: January 2009

AbstractNeurons in ventral pallidum fire to reward and its predictive cues. We tested mesolimbic activation effects on neural reward coding. Rats learned that a Pavlovian conditioned stimulus (CS+1 tone) predicted a second conditioned stimulus (CS+2 feeder click) followed by an unconditioned stimulus (UCS sucrose reward). Some rats were sensitized to amphetamine after training. Electrophysiological activity of ventral pallidal neurons to stimuli was later recorded under the influence of vehicle or acute amphetamine injection. Both sensitization and acute amphetamine increased ventral pallidum firing at CS+2 (population code and rate code). There were no changes at CS+1 and minimal changes to UCS. With a new ‘Profile Analysis’, we show that mesolimbic activation by sensitization/amphetamine incrementally shifted neuronal firing profiles away from prediction signal coding (maximal at CS+1) and toward incentive coding (maximal at CS+2), without changing hedonic impact coding (maximal at UCS). This pattern suggests mesolimbic activation specifically amplifies a motivational transform of CS+ predictive information into incentive salience coded by ventral pallidal neurons. Our results support incentive‐sensitization predictions and suggest why cues temporally proximal to drug presentation may precipitate cue‐triggered relapse in human addicts.
Lentivector‐mediated delivery of GDNF protects complex motor functions relevant to human Parkinsonism in a rat lesion model
Authors: Dowd Eilís , Monville Christelle , Torres Eduardo M. , Wong Liang‐Fong , Azzouz Mimoun , Mazarakis Nicholas D. , Dunnett Stephen B. 
Published: January 2009

AbstractAlthough viral vector‐mediated delivery of glial cell‐line derived neurotrophic factor (GDNF) to the brain has considerable potential as a neuroprotective strategy in Parkinson's disease (PD), its ability to protect complex motor functions relevant to the human condition has yet to be established. In this study, we used an operant task that assesses the selection, initiation and execution of lateralized nose‐pokes in Lister Hooded rats to assess the efficacy with which complex behaviours are protected against neurotoxic lesions by prior injection of a lentiviral vector expressing GDNF. Unilateral injection of 6‐hydroxydopamine (6‐OHDA) into the medial forebrain bundle (MFB) caused rats to attempt fewer trials and to make more procedural errors. Lesioned rats also developed a pronounced ipsilateral bias, with a corresponding drop in contralateral accuracy. They were also slower to react to contralateral stimuli and to execute movements bilaterally. Rats that were pre‐treated 4 weeks prior to lesion surgery with an equine infectious anaemia virus (EIAV) vector carrying GDNF [EIAV‐GDNF, injected into the striatum and above the substantia nigra (SN)] performed significantly better on all of these parameters than control rats. In addition to the operant task, EIAV‐GDNF successfully rescued contralateral impairments in the corridor, staircase, stepping and cylinder tasks, and prevented drug‐induced rotational asymmetry. This study confirms that GDNF can protect against 6‐OHDA‐induced impairments in complex as well as simple behaviours, and reinforces the use of EIAV‐based vectors for the treatment of PD.
GABAergic synaptic transmission modulates swimming in the ascidian larva
Authors: Brown E. R. , Nishino A. , Bone Q. , Meinertzhagen I. A. , Okamura Y. 
Published: January 2009

AbstractTo examine the role of the amino acid GABA in the locomotion of basal chordates, we investigated the pharmacology of swimming and the morphology of GABA‐immunopositive neurones in tadpole larvae of the ascidians Ciona intestinalis and Ciona savignyi. We verified that electrical recording from the tail reflects alternating muscle activity during swimming by correlating electrical signals with tail beats using high‐speed video recording. GABA reversibly reduced swimming periods to single tail twitches, while picrotoxin increased the frequency and duration of electrical activity associated with spontaneous swimming periods. Immunocytochemistry for GABA revealed extensive labelling throughout the larval central nervous system. Two strongly labelled regions on either side of the sensory vesicle were connected by an arc of labelled fibres, from which fibre tracts extended caudally into the visceral ganglion. Fibre tracts extended ventrally from a third, more medial region in the posterior sensory vesicle. Two rows of immunoreactive cell bodies in the visceral ganglion extended neurites into the nerve cord, where varicosities were seen. Thus, presumed GABAergic neurones form a network that could release GABA during swimming that is involved in modulating the time course and frequency of periods of spontaneous swimming. GABAergic and motor neurones in the visceral ganglion could interact at the level of their cell bodies and/or through the presumed GABAergic fibres that enter the nerve cord. The larval swimming network appears to possess some of the properties of spinal networks in vertebrates, while at the same time possibly showing a type of peripheral innervation resembling that in some protostomes.
Chronic nicotine exposure during adolescence differentially influences calcium‐binding proteins in rat anterior cingulate cortex
Authors: Liu Jen‐Jane , Mohila Carrie A. , Gong Yuna , Govindarajan Nalini , Onn Shao‐Pii 
Published: January 2009

AbstractWe have recently shown that chronic amphetamine exposure selectively up‐regulates parvalbumin (PV) calcium‐binding proteins in the anterior cingulate cortex (ACC). In this study, we evaluated the effects of chronic nicotine (NIC) exposure on PV, calbindin D28k (CB) and calretinin (CR) calcium‐binding protein immunostaining in ACC GABAergic interneurons. Chronic NIC exposure for 3 weeks in adolescent rats, either via drinking water (the oral group) or by twice daily subcutaneous injections (the injection group), resulted in the expression of high levels of CR proteins in the ACC but not in the parietal cortex. Larger increases in the density of CR‐immunoreactive (ir) neurons were noted in the NIC‐injected rats at 0‐day withdrawal (45% increase) compared with the oral group (26% increase). The larger increases in CR‐ir neuron density in the NIC‐injected rats were also reflected by prominent CR‐ir processes across cortical layers. The density of PV‐ir neurons was also increased (37%) at 0‐day withdrawal but only in the oral NIC group and no changes in CB‐ir neuron density were observed in either NIC group. Combined dual‐immunofluorescence and confocal microscopy revealed that somatodendritic α4 nicotinic acetylcholine receptors colocalized with cortical neurons stained positively for CR, PV or CB. These results suggest that CR‐ and/or PV‐ir‐containing GABA interneurons may be involved in channeling the effects of NIC in the ACC, which is closely associated with the ventral basal ganglia circuit that is linked to brain reward function.
Imaging LTP of presynaptic release of FM1‐43 from the rapidly recycling vesicle pool of Schaffer collateral–CA1 synapses in rat hippocampal slices
Authors: Stanton Patric K. , Winterer Jochen , Zhang Xiao‐lei , Müller Wolfgang 
Published: January 2009

AbstractRecent studies using the styryl dye FM1‐43 and two‐photon microscopy to directly visualize transmitter release at CA3–CA1 excitatory synapses in the hippocampus have demonstrated that activity‐dependent long‐term potentiation (LTP) and long‐term depression are associated with alterations in vesicular release. It is not known whether particular vesicle pools preferentially express these alterations or what second messenger cascades are involved. To address these questions, we selectively loaded FM1‐43 into the rapidly recycling pool (RRP) of vesicles by use of a brief hypertonic shock to release and load the RRP. We demonstrate here that the induction of LTP can lead to a selective long‐lasting enhancement in presynaptic release from the RRP, while reserve pool kinetics remain unchanged. LTP of RRP release was N‐methyl‐d‐aspartate receptor‐dependent and also required production of the intercellular messenger NO and activation of receptor tyrosine kinase. Measurement of FM1‐43 stimulus‐evoked uptake rates following induction of LTP confirmed that LTP produces more rapid recycling of vesicles released by electrical stimulation, consistent with an enhanced release probability from the RRP.
Reconfiguration of multiple motor networks by short‐ and long‐term actions of an identified modulatory neuron
Authors: Faumont Serge , Combes Denis , Meyrand Pierre , Simmers John 
Published: January 2009

AbstractThe pyloric and gastric motor pattern‐generating networks in the stomatogastric ganglion of the lobster Homarus gammarus are reconfigured into a new functional circuit by burst discharge in an identified pair of modulatory projection interneurons, originally named the pyloric suppressor (PS) neurons because of their inhibitory effects on pyloric network activity. Here we elucidate the actions of the PS neurons on individual members of the neighbouring gastric circuit, as well as describing their ability to alter synaptic coupling between the two networks. PS neuron firing has two distinct effects on gastric network activity: an initial short‐lasting action mediated by transient inhibition of most gastric motoneurons, followed by a long‐lasting circuit activation associated with a prolonged PS‐evoked depolarization of the medial gastric (MG) motoneuron and the single network interneuron, Int1. These long‐lasting effects are voltage‐dependent, and experiments with hyperpolarizing current injection and photoablation suggest that excitation of both the MG neuron and Int1 is critical for PS‐elicited gastric network rhythmicity. In parallel, PS neuron discharge persistently (lasting several minutes) enhances the strength of an inhibitory synaptic influence of the MG neuron on the pyloric dilator (PD)–anterior burster (AB) pacemaker neurons, thereby facilitating operational fusion of the two networks. Therefore, a single modulatory neuron may influence disparate populations of neurons via a range of very different and highly target‐specific mechanisms: conventional transient synaptic drive and up‐ or down‐modulation of membrane properties and synaptic efficacy. Moreover, distinctly different time courses of these actions allow different circuit configurations to be specified sequentially by a given modulatory input.
Post‐conditioning with lipopolysaccharide reduces the inflammatory infiltrate to the injured brain and spinal cord: a potential neuroprotective treatment
Authors: Davis Andrew E. M. , Campbell Sandra J. , Wilainam Panop , Anthony Daniel C. 
Published: January 2009

AbstractSystemic infection often accompanies or precedes acute brain injury, but it remains unclear how the systemic response contributes to outcome. To examine this problem we have microinjected recombinant interleukin‐1beta (IL‐1β), a cytokine associated with acute brain injury, into the rat brain parenchyma and either preceded or followed this challenge with the intravenous injection of lipopolysaccharide (LPS), which mimics systemic inflammatory response syndrome. The microinjection of IL‐1β alone into the brain parenchyma gives rise to leukocyte mobilization in the blood, and to the delayed recruitment of neutrophils and monocytes to the brain with no evidence of blood–brain barrier breakdown or overt neuronal cell death. Systemic LPS pre‐conditioning resulted in a dose‐dependent reduction both in the number of circulating leukocytes and in the number of leukocytes recruited to the brain parenchyma after 12 h. Surprisingly, LPS given two hours after injury was equally effective in reducing the recruitment of leukocytes to the brain, which is more relevant to the management of clinical disease. In a more clinically relevant model of spinal cord injury, intravenous LPS post‐conditioning also reduced the numbers of leukocytes mobilized in the blood and recruited to the spinal cord and thus limited the breakdown of the blood–spinal cord barrier. The effects appear to be specific to LPS, as they were not observed after intravenous IL‐1β pre‐conditioning. Our studies suggest that individual pro‐inflammatory conditioning strategies may protect the injured central nervous system from the damaging consequences of leukocyte recruitment and may provide scope for novel therapeutic intervention.
GABARAP is not essential for GABAA receptor targeting to the synapse
Authors: O'Sullivan Gregory A. , Kneussel Matthias , Elazar Zvulun , Betz Heinrich 
Published: January 2009

AbstractGABAA receptors (GABAARs) containing the γ2 subunit are thought to require the interacting protein GABARAP (GABAAR associated protein) for trafficking to the neuronal plasma membrane. In order to assess whether GABARAP is required for GABAA receptor accumulation at synaptic sites, we analysed a GABARAP knockout mouse. GABARAP deficient mice are phenotypically normal and do not show up‐regulation of other GABARAP homologues. Also, the total number of GABAARs, as assessed by benzodiazepine binding, is unaffected by the loss of GABARAP. Immunocytochemistry of cortical sections showed no differences in the expression and punctate distribution of the γ2 subunit and the receptor anchoring protein gephyrin between GABARAP deficient and wild‐type mice. Thus, GABARAP is not essential for trafficking γ2 subunit containing GABAARs to the neuronal plasma membrane or targeting them to inhibitory synapses.