bluuebunny/crossref_metadata_2025_split huggingface dataset:
Overexpression of a cell wall glycoprotein in Fusarium oxysporum increases virulence and resistance to a plant PR‐5 protein
Authors: Narasimhan Meena L. , Lee Hyeseung , Damsz Barbara , Singh Narendra K. , Ibeas José I. , Matsumoto Tracie K. , Woloshuk Charles P. , Bressan Ray A. 
Published: October 2003

Summary Fusarium oxysporum f. sp. nicotianae is a causal agent for vascular wilt disease in tobacco. It is sensitive to osmotin, a tobacco pathogenesis‐related protein (PR‐5) that is implicated in plant defense against phytopathogenic fungi. We show that osmotin susceptibility of F. oxysporum f. sp. nicotianae was reduced by overexpression of the heterologous cell wall glycoprotein Saccharomyces cerevisiae protein containing inverted repeats (PIR2), a member of the PIR family of fungal cell wall glycoproteins that protect S. cerevisiae from the toxic action of osmotin. S. cerevisiae PIR2 was targeted to the cell wall of F. oxysporum. Disease severity and fungal growth were increased in tobacco seedlings inoculated with F. oxysporum transformed with PIR2 compared to seedlings infected with untransformed F. oxysporum or that transformed with vector, although accumulation of transcript and protein of defense genes was similar. The results show that fungal cell wall components can increase resistance to plant defense proteins and affect virulence.
The phenotype of the Arabidopsis cue1 mutant is not simply caused by a general restriction of the shikimate pathway
Authors: Voll Lars , Häusler Rainer E. , Hecker Rolf , Weber Andreas , Weissenböck Gottfried , Fiene Gabriele , Waffenschmidt Sabine , Flügge Ulf‐Ingo 
Published: October 2003

SummaryThe Arabidopsis thalianachlorophyll a/b binding protein underexpressed (cue1) mutant, which has been isolated in a screen for chlorophyll a/b binding protein (CAB) underexpressors, exhibits a reticulate leaf phenotype combined with delayed chloroplast development and aberrant shape of the palisade parenchyma cells. The affected gene in cue1 is a phosphoenolpyruvate (PEP)/phosphate translocator (PPT) of the plastid inner envelope membrane. The proposed function of the PPT in C3‐plants is the import of PEP into the stroma as one of the substrates for the shikimate pathway, from which aromatic amino acids and a variety of secondary plant products derive. The mutant phenotype could be: (i) complemented by constitutive overexpression of a heterologous PPT from cauliflower; and (ii) rescued by overexpression of a C4‐type pyruvate,orthophosphate dikinase (PPDK). The latter approach indicates that PEP deficiency within plastids triggers developmental constraints in cue1. The impact of the mutation on aspects of primary and secondary metabolism was assessed in cue1 as well as in the individual transformant lines. The majority of the data obtained in this and an accompanying paper suggest that the mutant phenotype is not simply caused by a general restriction of the shikimate pathway because of a defect in a PPT.
Short‐term subjective efficacy of doxazosin in predicting probability of prostatectomy in the management of benign prostatic hyperplasia in patients with severe symptoms
Authors: CAM KAMIL , AKMAN YAVUZ , KAYIKCI ALI , SENEL FERDA , EROL ALI 
Published: October 2003

AbstractBackground:  The severity of symptoms still constitutes the major indication for transurethral prostatectomy, despite the extensive utilization of medical treatments. The aim of the study presented here was to investigate the impact of doxazosin on symptoms in relation to the probability of consequent surgery in severely symptomatic patients.Methods:  Patients with an International Prostate Symptom Score (IPSS) between 18 and 35 were included in the study. The patients received 4 mg/day doxazosin, and subjective efficacy was assessed by IPSS at the first and third months. In addition, the patients were classified at the third month according to a single question regarding satisfaction with medical treatment in terms of symptom relief as ‘ineffective, no change, and effective’.Results:  A total of 178 patients constituted the study group. Mean total symptom scores were 24, 19 and 17 at baseline, first and third months, respectively (P < 0.05). According to results of the questionnaire, 23% of the patients claimed the treatment was ineffective, and subsequently, the majority of this group (93%) underwent prostatectomy in a year. In addition, 33% of the patients reported no change in their symptoms, while 44% reported that the medication was effective. However, after 1 year, 59% and 15% of these cases underwent surgical treatment, respectively. The probability of surgery in the ‘ineffective’ group was significantly higher compared to the remaining groups (P < 0.05).Conclusion:  The majority of patients with severe symptoms who were not satisfied with the medication at the 3rd month underwent surgery. This observation may provide a predictor for subsequent probability of prostatectomy. Therefore, reassessment of patients would be a cost‐effective approach for the treatment of BPH in severely symptomatic patients.
Generation of retinal ganglion cells is modulated by caspase‐dependent programmed cell death
Authors: Mayordomo Raquel , Valenciano Ana I. , De La Rosa Enrique J. , Hallböök Finn 
Published: October 2003

AbstractProgrammed cell death occurs during both early and late neural development. The mechanisms for the regulation and execution of the early cell death as well as its developmental role are still not fully understood. In this work we have studied the early programmed cell death in the retinal neuroepithelium. Apoptotic cells were selectively located around the optic nerve head in the retinal neuroepithelium of 2‐ to 6‐day‐old chick embryos. TUNEL‐positive cells and cells which were immunostained for activated caspase‐3 showed overlapping distributions suggesting that caspase‐3 is involved in the early retinal cell death. Caspase‐3 involvement in early retinal cell death was also demonstrated by in vivo treatment with caspase inhibitors z‐DEVD‐fmk and Boc‐D‐fmk. After 6 h of treatment, the number of TUNEL‐positive cells was reduced by 50%. Sustained treatments (20 h) resulted in a slight widening in the central part of the neural retina but the retinal ganglion cell axons maintained their organization and navigation towards the optic fissure. The most prominent result after inhibition of cell death was an increase in the number of retinal ganglion cells which also produced an enlargement of the ganglion cell layer and an increased number of ganglion cell axons. In conclusion, our results show that caspase‐dependent programmed cell death occurs in the embryonic chick retina and that it plays a role to modulate the generation of retinal ganglion cells.
Complementary distribution of type 1 cannabinoid receptors and vesicular glutamate transporter 3 in basal forebrain suggests input‐specific retrograde signalling by cholinergic neurons
Authors: Harkany Tibor , Härtig Wolfgang , Berghuis Paul , Dobszay Marton B. , Zilberter Yuri , Edwards Robert H. , Mackie Ken , Ernfors Patrik 
Published: October 2003

AbstractBasal forebrain cholinergic neurons project to diverse cortical and hippocampal areas and receive reciprocal projections therefrom. Maintenance of a fine‐tuned synaptic communication between pre‐ and postsynaptic cells in neuronal circuitries also requires feedback mechanisms to control the probability of neurotransmitter release from the presynaptic terminal. Release of endocannabinoids or glutamate from a postsynaptic neuron has been identified as a means of retrograde synaptic signalling. Presynaptic action of endocannabinoids is largely mediated by type 1 cannabinoid (CB1) receptors, while fatty‐acid amide hydrolase (FAAH) is involved in inactivating some endocannabinoids postsynaptically. Alternatively, vesicular glutamate transporter 3 (VGLUT3) controls release of glutamate from postsynaptic cells. Here, we studied the distribution of CB1 receptors, FAAH and VGLUT3 in cholinergic basal forebrain nuclei of mouse and rat. Cholinergic neurons were devoid of CB1 receptor immunoreactivity. A fine CB1 receptor‐immunoreactive (ir) fibre meshwork was present in medial septum, diagonal bands and nucleus basalis. In contrast, the ventral pallidum and substantia innominata received dense CB1 receptor‐ir innervation and cholinergic neurons received CB1 receptor‐ir presumed synaptic contacts. Consistent with CB1 receptor distribution, FAAH‐ir somata were abundant in basal forebrain and appeared in contact with CB1 receptor‐containing terminals. Virtually all cholinergic neurons were immunoreactive for FAAH. A significant proportion of cholinergic cells exhibited VGLUT3 immunoreactivity in medial septum, diagonal bands and nucleus basalis, and were in close apposition to VGLUT3‐ir terminals. VGLUT3 immunoreactivity was largely absent in ventral pallidum and substantia innominata. We propose that specific subsets of cholinergic neurons may utilize endocannabinoids or glutamate for retrograde control of the efficacy of input synapses, and the mutually exclusive complementary distribution pattern of CB1 receptor‐ir and VGLUT3‐ir fibres in basal forebrain suggests segregated input‐specific signalling mechanisms by cholinergic neurons.
Facilitation of conditioned taste aversion learning by systemic amphetamine: role of nucleus accumbens shell dopamine D1 receptors
Authors: Fenu Sandro , Di Chiara Gaetano 
Published: October 2003

AbstractThe role of dopamine (DA) in associative learning was studied in a conditioned taste aversion (CTA) paradigm with sucrose as the conditioned stimulus (CS) and intraperitoneal lithium chloride as the unconditioned stimulus (US). Drinking on trial of a 15% sucrose solution followed 1 h later by lithium chloride (20 or 40 mg/kg i.p.) resulted in mild CTA, as shown by reduction of drinking of the sucrose solution 24 h later. Amphetamine sulphate (0.125, 0.25, 0.50 and 1.0 mg/kg s.c.), administered on trial 5 min after sucrose drinking, facilitated CTA with maximal effects at 0.25 mg/kg s.c. Amphetamine given in the absence of lithium or 45 min after sucrose did not affect sucrose intake. The DA D1 receptor antagonist SCH 39166, administered before amphetamine either systemically (0.0125 mg/kg s.c.) or in the nucleus accumbens shell (NAc; 0.025 µg/µL on each side) prevented the facilitation of CTA induced by amphetamine. It is concluded that amphetamine facilitates CTA learning by strengthening the consolidation of gustatory short‐term memory via D1 receptors of the NAc shell.
The rat nucleus accumbens is involved in guiding of instrumental responses by stimuli predicting reward magnitude
Authors: Giertler Christian , Bohn Ines , Hauber Wolfgang 
Published: October 2003

AbstractThe present study examined the involvement of N‐methyl‐d‐aspartate (NMDA), α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazolpropionate/kainate (AMPA/KA) and dopamine receptors in the nucleus accumbens (ACB) in influencing reaction times of instrumental responses by the expectancy of reward. A simple reaction time task demanding conditioned lever release was used in which the upcoming reward magnitude was signalled in advance by discriminative cues. After training, in control rats with vehicle infusions (0.5 µL) into the ACB, reaction times of responses were significantly shorter to the discriminative cue predictive of high reward magnitude. Indirect stimulation of dopamine receptors in the ACB by d‐amphetamine (20 µg/0.5 µL) decreased reaction times, impaired their guidance by cue‐associated reward magnitudes and reduced the accuracy of task performance. Blockade of AMPA/KA receptors in the ACB by 6‐cyano‐7‐nitroquino‐xaline‐2,3‐dione (0.75 and 2.5 µg/0.5 µL) or NMDA receptors by d(−)‐2‐amino‐5‐phosphonopentanoic acid (5 µg/0.5 µL) produced a general increase in reaction times, but left guidance of reaction times by cue‐associated reward magnitudes unaffected. Thus, stimulation of intra‐ACB ionotropic glutamate receptors is critically involved in modulating the speed of instrumental responding to cues predictive for reward magnitude, but is not required for intact performance of previously learned instrumental behaviour.
The growth of cat cerebral cortex in postnatal life: a magnetic resonance imaging study
Authors: Rathjen Stefan , Engelmann Ralf , Struif Stefan , Kaulisch Thomas , Stiller Detlef , Löwel Siegrid 
Published: October 2003

AbstractTo follow up the development of an individual brain over time and to measure its growth we have analysed the brains of individual cats from postnatal day 12 to adulthood using magnetic resonance imaging. From the anatomical images, four parameters were calculated: anteroposterior extent of the telencephalon, brain volume, neocortical surface area and neocortical volume. The development of the anteroposterior extent was similar in all cats. It increased between the 3rd and 6th postnatal week from 33 to 37.5 mm ending up ≈ 40 mm in adulthood. The brain volume showed greater variability. On average, the volume increased from 11.5 to 16.5 cm3 in the same period. Adult values were ≈ 19 cm3. Considerable interindividual variability was observed in neocortical surface area. In one cat, it expanded from 12.5 to 26 cm2 between days 14 and 41. In another cat, this area expanded from 16 to 24.5 cm2 between days 12 and 40. On average, the surface area expanded by 34% between the 3rd and 6th week. Adult values ranged from 27 to 30 cm2. Neocortical volume increased from 2.9 to 4.1 cm3 between the 3rd and 6th postnatal week and to 4.5–5.2 cm3 in adulthood. The asymmetry between the hemispheres in both neocortical surface area and volume was < 3% in all animals for most of the observation period. Comparison of the neocortical surface measurements with data on postnatal growth of cat primary visual cortex obtained by 2‐deoxyglucose autoradiography indicates that the primary visual cortex grows at the same speed and amounts to ≈ 15% of the entire neocortical surface area throughout development.
Basal and morphine‐evoked dopaminergic neurotransmission in the nucleus accumbens of MOR‐ and DOR‐knockout mice
Authors: Chefer Vladimir I. , Kieffer Brigitte L. , Shippenberg Toni S. 
Published: October 2003

AbstractConventional and no net flux microdialysis were used to quantify basal and morphine‐induced extracellular dopamine (DA) levels and the basal extraction fraction, which provides an estimate of the rate of DA uptake, in the nucleus accumbens (NAc) of wild‐type mice and those with a constitutive deletion of mu (MOR)‐ or delta (DOR)‐opioid receptors. Locomotor activity was assessed in these same animals. No difference between genotypes in basal dialysate DA levels was seen. No net flux studies revealed significant decreases in the DA extraction fraction in both MOR‐ and DOR‐knockout mice, indicating decreased basal DA uptake in both genotypes. Extracellular DA, however, was unchanged. Because extracellular neurotransmitter levels are determined by the dynamics of both release and uptake, these findings provide suggestive evidence that basal DA release is decreased in mutant mice. Systemic administration of morphine significantly increased locomotor activity and dialysate DA levels in wild‐type mice. MOR‐knockout mice failed to exhibit a behavioural response to morphine. The ability of morphine to increase DA levels, however, was reduced but not prevented. No alteration in the effects of morphine was observed in DOR‐knockout mice. These data provide genetic evidence for the existence of tonically active MOR and DOR systems that modulate basal DA neurotransmission in the NAc. Furthermore, they demonstrate that in contrast to the locomotor‐activating effects of morphine, a small component of morphine‐evoked DA release occurs independently of MOR activation.
Neuronal activity in primate dorsolateral and orbital prefrontal cortex during performance of a reward preference task
Authors: Wallis Jonathan D. , Miller Earl K. 
Published: October 2003

AbstractAn important function of the prefrontal cortex (PFC) is the control of goal‐directed behaviour. This requires information as to whether actions were successful in obtaining desired outcomes such as rewards. While lesion studies implicate a particular PFC region, the orbitofrontal cortex (OFC), in reward processing, neurons encoding reward have been reported in both the OFC and the dorsolateral prefrontal cortex (DLPFC). To compare and contrast their roles, we recorded simultaneously from both areas while two rhesus monkeys (Macaca mulatta) performed a reward preference task. The monkeys had to choose between pictures associated with different amounts of a juice reward. Neuronal activity in both areas reflected the reward amount. However, neurons in the DLPFC encoded both the reward amount and the monkeys' forthcoming response, while neurons in the OFC more often encoded the reward amount alone. Further, reward selectivity arose more rapidly in the OFC than the DLPFC. These results are consistent with reward information entering the PFC via the OFC, where it is passed to the DLPFC and used to control behaviour.
Dynamic increases in dopamine during paced copulation in the female rat
Authors: Jenkins William J. , Becker Jill B. 
Published: October 2003

AbstractThe role of dopamine in the rewarding aspects of sexual behaviour in female rats was investigated. This is a unique model because sexual behaviour is only rewarding when copulatory stimuli are experienced at the preferred rate of copulation for a female rat. In addition, increases in dopamine in the nucleus accumbens occur during sexual behaviour only when the female achieves this preferred rate of copulation. In this study, minute‐by‐minute changes in nucleus accumbens dopamine were monitored using in vivo microdialysis. We report here that extracellular dopamine in the nucleus accumbens increases before coital stimulation only when sexual behaviour is occurring under conditions that are rewarding to the female rat. We conclude that increases in dopamine in the nucleus accumbens are involved in anticipation, not consummation, of sexual behaviour in the female rat.
A comparison of different models of stroke on behaviour and brain morphology
Authors: Gonzalez C.L.R. , Kolb B. 
Published: October 2003

AbstractWe compared the effects of three models of permanent ischemia, as well as cortical aspiration, on behaviour and brain morphology. Rats received a stroke either by devascularization or by two different procedures of medial cerebral artery occlusion (MCAO; small vs. large). Animals were trained in a reaching task, forepaw asymmetry, forepaw inhibition, sunflower seed task and tongue extension. Behaviour was assessed 1 week after the lesion and at 2‐week intervals for a total of 9 weeks. One week after the surgery all animals were severely impaired on all tasks and although they improved over time they only reached preoperative base lines on tongue extension. Animals with small MCAOs performed better in reaching and sunflower tasks; no other behavioural differences were detected among the groups. Pyramidal cells in forelimb and cingulate areas as well as spiny neurons of the striatum were examined for dendritic branching and spine density using a Golgi–Cox procedure. Each lesion type had a different impact on cell morphology. Overall, different changes (atrophy or hypertrophy) were observed with each kind of lesion and these changes were specific for the region (forelimb, cingulate, striatum) and the condition (intact vs. damaged hemisphere). These results suggest that: (i) different lesions to the motor cortex produce subtle differences in behaviour, and (ii) the method used to induce the lesion produces striking differences in cortical and subcortical plasticity.
Up‐regulation of fatty acid metabolizing‐enzymes mRNA in rat spinal cord during persistent peripheral local inflammation
Authors: Benani A. , Vol C. , Heurtaux T. , Asensio C. , Dauça M. , Lapicque F. , Netter P. , Minn A. 
Published: October 2003

AbstractPersistent peripheral inflammation is associated with repetitive painful inputs into the spinal cord, leading to a chronic pain state. Related dramatic changes occur in the central nervous system (CNS) including central sensitization, which results in hyperalgesia. This neural plasticity involves in part fatty acids as functional and structural compounds. We hypothesized that central modification of fatty acids metabolism might occur after prolonged peripheral noxious stimulation. In the present study, the regulation of genes involved in fatty acids metabolism in the rat CNS was investigated during a chronic pain state. Using semiquantitative RT‐PCR, we explored in the neuraxis the mRNA expression of brain acyl‐CoA synthetases (ACS) and acyl‐CoA oxidase (ACO), which are major fatty acid‐metabolizing enzymes, following complete Freund's adjuvant (CFA) injection into a hind paw. Similar spinal up‐regulation of the isoforms ACS2, ACS3, ACS4, and of ACO was detected early after 30 min, reaching a maximal after 6 h post‐injection. Other peaks were also observed after 4 and 21 days post‐inoculation, corresponding to the acute and chronic inflammation, respectively. Induction occurred only in the lumbar spinal cord ipsilaterally to the inflamed paw and was completely inhibited by a local anaesthesia of the sciatic nerve, suggesting a neural transmission of the inducing signal. Moreover, intrathecal injection of MK801, a noncompetitive NMDA antagonist, partially prevented these inductions, highlighting the involvement of the neurotransmitter glutamate in the central ACS and ACO up‐regulation. These findings suggest that the fatty metabolism is stimulated in the CNS during a chronic pain state.
Extrinsic regulation of injury/growth‐related gene expression in the inferior olive of the adult rat
Authors: Buffo Annalisa , Carulli Daniela , Rossi Ferdinando , Strata Piergiorgio 
Published: October 2003

AbstractSuccessful axon regeneration relies on the capability of the lesioned neurons to up‐regulate a specific set of injury/growth‐associated genes. In the adult central nervous system, the strength of the cell body response is generally related to the distance of the injury site from the perikaryon, being stronger for proximal lesions. Nevertheless, inferior olive (IO) cells react to injury and regenerate their axons even after distal transections. To investigate the mechanisms that regulate the IO growth properties, we examined the expression of injury/growth markers (nitric oxide synthase, growth‐associated protein 43 and c‐Jun) after target deletion or axotomy performed at different sites along the olivocerebellar pathway. Both axon injury and target loss disclose two subsets of IO neurons distributed within precise subnuclei: one subset up‐regulates all markers in all conditions, whereas the other shows a mild c‐Jun expression but remains unresponsive even after a very proximal axotomy. These observations indicate that distinct subpopulations of IO cells respond to different regulatory strategies. Unresponsive neurons appear insensitive to environmental positive or negative cues, suggesting that they are intrinsically unable to set up a cellular reaction to injury. In contrast, cell body changes in reactive neurons are elicited after the removal of retrogradely transported target‐derived inhibitory signals. Target loss also induces degeneration of IO cells, whose survival remains partially dependent on Purkinje targets in adulthood. Thus, the intrinsic regenerative potential of a functionally homogeneous population is regulated by multiple mechanisms, specific for distinct neuronal subsets.