bluuebunny/crossref_metadata_2025_split huggingface dataset:
L‐type calcium channels and NMDA receptors: a determinant duo for short‐term nociceptive plasticity
Authors: Fossat Pascal , Sibon Igor , Le Masson Gwendal , Landry Marc , Nagy Frédéric 
Published: January 2007

AbstractIn the dorsal horn of the spinal cord, pain‐transmitting neurons exhibit action potential windup, a form of short‐term plasticity, which consists of a progressive increase in neuronal response during repetitive stimulation of nociceptive input fibers. Windup depends on N‐methyl‐d‐aspartate (NMDA) receptor activation, but previous in vitro studies indicated that windup also relies on intrinsic plateau properties of spinal neurons. In the present study, we considered the possible involvement of these properties in windup in vivo. For this purpose, we first studied a nociceptive flexion reflex in the rat. We showed that windup of the reflex is actually suppressed by blockers of L‐type calcium current and Ca2+‐activated non‐specific cationic current (Ican), the two main depolarizing conductances of plateau potentials. We further showed that, during windup, NMDA receptors provide a critical excitatory component in a dynamic balance of excitatory and inhibitory inputs which ultimately activates L‐type calcium channels. The nociceptive reflex involves at least two neuronal groups, which may express intrinsic amplification properties, motor neurons and dorsal horn neurons. By means of extracellular recordings in the dorsal horn, we showed that windup of dorsal horn neuron discharge was sensitive to the modulators of L‐type calcium current. Altogether, our results suggest that, in vivo, windup also depends on the amplification properties of spinal neurons, the triggering of which requires previous activation of NMDA receptors.
Visualization of corticofugal projections during early cortical development in a τ‐GFP‐transgenic mouse
Authors: Jacobs Erin C. , Campagnoni Celia , Kampf Kathy , Reyes Samuel D. , Kalra Vikram , Handley Vance , Xie Yuan‐Yun , Hong‐Hu Yan , Spreur Vilma , Fisher Robin S. , Campagnoni Anthony T. 
Published: January 2007

AbstractThe first postmitotic neurons in the developing neocortex establish the preplate layer. These early‐born neurons have a significant influence on the circuitry of the developing cortex. However, the exact timing and trajectory of their projections, between cortical hemispheres and intra‐ and extra‐cortical regions, remain unresolved. Here, we describe the creation of a transgenic mouse using a 1.3 kb golli promoter element of the myelin basic protein gene to target expression of a τ–green fluorescent protein (GFP) fusion protein in the cell bodies and processes of pioneer cortical neurons. During embryonic and early neonatal development, the timing and patterning of process extension from these neurons was examined. Analysis of τ‐GFP fluorescent fibers revealed that progression of early labeled projections was interrupted unexpectedly by transient pauses at the corticostriatal and telencephalic–diencephalic boundaries before invading the thalamus just prior to birth. After birth the pioneering projections differentially invaded the thalamus, excluding some nuclei, e.g. medial and lateral geniculate, until postnatal days 10–14. Early labeled projections were also found to cross to the contralateral hemisphere as well as to the superior colliculus. These results indicate that early corticothalamic projections appear to pause before invading specific subcortical regions during development, that there is developmental regulation of innervation of individual thalamic nuclei, and that these early‐generated neurons also establish early projections to commissural and subcortical targets.
Auditory processing in a patient with a unilateral lesion of the inferior colliculus
Authors: Champoux F. , Paiement P. , Mercier C. , Lepore F. , Lassonde M. , Gagné J.‐P. 
Published: January 2007

AbstractThe role of the inferior colliculus (IC) in human auditory processing is still poorly understood. We report here the results obtained with a 12‐year‐old boy (FX) who suffered a very circumscribed lesion of the right IC without additional neurological damage. The child underwent an extensive battery of psychophysical hearing tests. Results revealed normal peripheral auditory functioning, bilaterally. Furthermore, masking‐level differences and frequency‐pattern recognition were normal for each ear. When the right ear was stimulated, behavioural tests assessing central auditory processing yielded normal results. However, when the left ear was stimulated, speech recognition in the presence of a competing ipsilateral signal and duration‐pattern recognition were impaired. Similarly, performance on two dichotic speech recognition tests was poor when the target stimulus was presented in the left and the competing signal in the right ear. Finally, sound‐source localization in space was deficient for speakers located on the side contralateral to the lesion. The pattern of results suggests that auditory functions such as recognition of low‐redundancy speech presented monaurally, recognition of tone duration patterns, binaural separation and integration, as well as sound‐source localization in space, depend on the integrity of the bilateral auditory pathways at the IC level.
Regulation of ΔFosB transcriptional activity by Ser27 phosphorylation
Authors: Ulery Paula G. , Nestler Eric J. 
Published: January 2007

AbstractThe transcription factor, ΔFosB, is an important mediator of the long‐term plasticity induced in brain by chronic exposure to drugs of abuse, stress, or several other psychoactive stimuli. We have previously demonstrated that the casein kinase 2 (CK2)‐mediated phosphorylation of a highly conserved N‐terminal serine (Ser27) plays a critical role in regulating ΔFosB's unusual stability, while it does not affect that of the full‐length FosB protein. In the present study, we analysed whether CK2 and Ser27 phosphorylation also play a role in regulating ΔFosB's transcriptional activity. Our findings indicate that CK2 activation increases ΔFosB's transactivation potential, while CK2 inhibition decreases it. Further, we show that preventing Ser27 phosphorylation by mutating the site to Ala results in a significant decrease in ΔFosB transactivation, without affecting ΔFosB's subcellular localization or DNA‐binding affinity. In contrast, Ser27 does not seem to play a role in the transactivation potential of full‐length FosB. These findings constitute the first evidence of a role for phosphorylation in ΔFosB's transcriptional activity.
Enhanced fidelity of diffusive nitric oxide signalling by the spatial segregation of source and target neurones in the memory centre of an insect brain
Authors: Ott Swidbert R. , Philippides Andrew , Elphick Maurice R. , O'Shea Michael 
Published: January 2007

AbstractThe messenger molecule nitric oxide (NO) is a key mediator of memory formation that can diffuse in the brain over tens of micrometres. It would seem therefore that NO derived from many individual neurones may merge into a volume signal that is inevitably ambiguous, relatively unspecific and thus unreliable. Here we report on the neuronal architecture that supports the NO−cyclic GMP signalling pathway in the mushroom body of an insect brain, the key centre for associative learning. We show that, in the locust (Schistocerca gregaria), parallel axons of intrinsic neurones (Kenyon cells) form tubular NO‐producing zones surrounding central cores of NO‐receptive Kenyon cell axons, which do not produce NO. This segregated architecture requires NO to spread at physiological concentrations up to 60 µm from the tube walls into the central NO‐receptive cores. By modelling NO diffusion we show that a segregated architecture, which requires NO to act at a distance, affords significant advantages over a system where the same sources and targets intermingle. Segregation enhances the precision of NO volume signals by reducing noise and ambiguity, achieving a reliable integration of the activity of thousands of NO‐source neurones. In a neural structure that forms NO‐dependent associations, these properties of the segregated architecture may reduce the likelihood of forming spurious memories.
A novel enteropathogenic, strongly haemolytic spirochaete isolated from pig and mallard, provisionally designated ‘Brachyspira suanatina’ sp. nov.
Authors: Råsbäck Thérése , Jansson Désirée S. , Johansson Karl‐Erik , Fellström Claes 
Published: January 2007

SummaryAtypical, strongly haemolytic porcine isolates of intestinal spirochaetes differing genetically from Brachyspira hyodysenteriae were identified and characterized. The isolates were subjected to culture and biochemical tests, antimicrobial susceptibility testing and molecular analyses. None of four species‐specific polymerase chain reaction systems targeting genes of B. hyodysenteriae gave a positive reaction. All the atypical porcine isolates were identical in their partial 16S rRNA and nox gene sequences with a previously described isolate from a mallard (Anas platyrhynchos), and differed only slightly from another mallard isolate. All these isolates were distinctly different from all currently recognized Brachyspira species. A challenge study was carried out using recently weaned pigs. Clinical signs and macroscopic changes consistent with swine dysentery were seen both in pigs given the atypical porcine isolate and in control pigs given the reference strain of B. hyodysenteriae (B204R). Pigs given the genetically similar isolate from a mallard became colonized and diarrhoea was observed. This is the first study indicating that Brachyspira isolates from mallard can infect pigs and induce diarrhoea. We propose that this atypical spirochaete genotype should be regarded as a new species within the genus Brachyspira, and be provisionally designated ‘Brachyspira suanatina’ sp. nov.
Safe as Houses? Ageing in Place and Vulnerable Older People in the UK
Authors: Means Robin 
Published: January 2007

Abstract The UK is very similar to many other European, North American and Australasian countries in its emphasis on ‘ageing in place’. This article does not seek to challenge the importance of this for most older people but rather draws out the challenges and issues raised by older people who are vulnerable or in vulnerable housing situations. This is illustrated through drawing upon three separate studies which are on older homelessness, older people in the private rented sector and owner‐occupiers with dementia.
Optimal Additions to and Deletions from Two-Level Orthogonal Arrays
Authors: Butler Neil A. , Ramos Victorino M. 
Published: January 2007

SummaryConsider the problem of selecting a two-level factorial design. It is well known that two-level orthogonal arrays of strength 4 or more with e extra runs have various optimality properties including generalized Cheng (type 1) optimality when e=1, restricted Cheng (type 1) optimality when e=2 and E-optimality when 3⩽e⩽5. More general Schur optimality results are derived for more general values of e within the more restricted class of augmented two-level orthogonal arrays. Similar results are derived for the class of orthogonal arrays with deletions. Examples are used to illustrate the results and in many cases the designs are confirmed to be optimal across all two-level designs.
Nail changes in connective tissue diseases: do nail changes provide clues for the diagnosis?
Authors: Tunc SE , Ertam I , Pirildar T , Turk T , Ozturk M , Doganavsargil E 
Published: January 2007

AbstractObjective  To evaluate the frequency and the specificity of nail changes associated with connective tissue diseases (CTD).Methods  In a case–control study, 190 patients including those with systemic lupus erythematosus (SLE; 56), rheumatoid arthritis (RA, 47), primary Sjögren's syndrome (pSS; 35), systemic sclerosis (SSc; 39), and dermatomyositis/polymyositis (DM/PM; 13) were enrolled in the study. Patients with SLE and other CTDs were compared with two different control groups. Twenty nails were examined. Nail features were noted and classified. Nail samples were collected for mycological cultures.Results  In patients with SLE, erythema of proximal nailfold (P < 0.01), splinter haemorrhages in fingernails (P < 0.01), capillary loops in proximal nailfold (P < 0.05), periungual erythema (P < 0.05), and thin nail plates (P < 0.05) were more common than those in controls. Only splinter haemorrhages were associated with the disease activity. In patients with SSc and DM/PM, splinter haemorrhages (P < 0.05) and capillary loops in proximal nailfold (P < 0.01) in fingernails were common as well. Increase in longitudinal curvature (P < 0.001), transverse curvature (P < 0.01), and white dull colour in fingernails were other frequent findings in patients with SSc. Increase in transverse curvature was associated with the disease activity in SSc. In patients with RA, splinter haemorrhages (P < 0.05), red lunula (P < 0.05), and white dull colour (P < 0.05) in fingernails were frequent. The sensitivity values of all these changes were very low. However, their specificity values were found to be relatively high.Conclusion  Proximal nailfold is the most important site of affection in CTDs. These nail changes can be used in combination with highly sensitive diagnostic modalities to establish an accurate diagnosis.
Sun protection in Iranian kidney transplant recipients: knowledge, attitude and practice
Authors: Firooz A , Amin‐Nejad R , Bouzari N , Nafar M , Firoozan A , Mahdavi‐Mazdeh M 
Published: January 2007

AbstractBackground  Kidney transplant recipients (KTR) are at increased risk of developing skin cancer. The purpose of this study was to evaluate the knowledge, attitude, and practices of KTRs regarding skin cancer after transplantation and to identify the role of education in motivating these patients to practice sun‐protective behaviours.Methods  Two hundred and fifty KTRs in a referral hospital were interviewed using a questionnaire. All patients received a skin cancer information booklet after completion of the questionnaire. Six months later, these patients were invited and interviewed again about their skin cancer‐prevention practices.Results  The patients consisted of 153 men and 97 women patients with a mean age of 35.9 ± 14.2 years and mean of 49.7 ± 53.1 months after their transplantation. A total of 102 patients (40.8%) mentioned receiving skin care advice after transplantation. Nonetheless, the majority of patients did not have appropriate skin cancer‐prevention practices. Patients who had received advice on skin care after transplantation were significantly more likely to do skin self‐examination (chi‐squared test; P < 0.001) and have less sun exposure daily (Mann–Whitney test; P = 0.019) than those who did not. Half of the patients (125 patients) participated in the second part of the study 6 months after the first interview and providing skin care instruction booklet. Although regular skin self‐examination and sunscreen use was significantly increased (P = 0.006 and P = 0.001, respectively), but daily sun exposure was not changed significantly (P = 0.64).Conclusions  Post‐transplantation education does not necessarily lead to patients’ awareness about their increased risk of skin cancer, and subsequent motivation to practice effective sun protection. Health professionals and dermatologists in particular need to establish better methods of dissemination of information, repeatedly and at the proper time.
Mailed urine samples are not an effective screening approach for Chlamydia trachomatis case finding among young men
Authors: Domeika M , Oscarsson L , Hallén A , Hjelm E , Sylvan S 
Published: January 2007

AbstractBackground  Frequency of testing is known to be low for sexually transmitted infections (STIs) in men aged 20–24 years. The use of mailed, home‐obtained urine specimens could increase the uptake of young men and facilitate screening programmes for the detection of asymptomatic Chlamydia trachomatis.Objective  The aim of the present study is to evaluate the home screening approach as a tool for recruitment of asymptomatic men for screening of genital C. trachomatis infections.Methods  Men aged 19–24 years old (n = 1936) were invited to participate in home‐based testing for genital C. trachomatis infection. Persons who agreed to be tested were provided with a testing kit. Self‐collected first void urine was sent for testing to the microbiology laboratory. The test result was accessible on the study's web‐page 1 week after testing. Individuals with a diagnosed infection were instructed to contact the venereal disease department.Results  The response rate was 24% (462/1936). The responders’ main reason for not participating was a feeling of being safe regarding STIs (87%; 159/182). The primary reason for this feeling of safety was that the responders were in a steady relationship (59%; 107/159). Having sex outside a steady relationship was reported by 36% (90/250) of the responders. The prevalence of C. trachomatis infection among the responders was 2.02% and the reported history of chlamydial infection was 36% (34/95). Out of the responders, 92% (229/249) were, to varying degrees, concerned about getting STIs; however, the majority (72%; 174/242) estimated the risk to be low.Conclusion  Home screening using web‐based answer management is a feasible tool for STI screening, which lowers the threshold for people at risk. In this particular population, however, the response rate was too low to be routinely introduced.
Modulation of P‐glycoprotein function by sphingosine kinase‐1 in brain endothelial cells
Authors: Pilorget Anthony , Demeule Michel , Barakat Stéphane , Marvaldi Jacques , Luis José , Béliveau Richard 
Published: January 2007

AbstractP‐glycoprotein (P‐gp), an ABC‐transporter highly expressed in brain capillaries, protects the brain by extruding xenobiotics. However, its overexpression has also been associated with the multidrug resistance phenotype in tumors. Here, we have investigated the regulation of P‐gp transport activity by sphingosine kinase 1 (SphK‐1) in brain endothelial cells. We first demonstrated that SphK‐1 is overexpressed in endothelial cells (EC) isolated from rat brain tumors compared with EC from normal brain. We also provide evidence that the overexpression of SphK‐1 in the cerebral EC line RBE4 leads to the up‐regulation of P‐gp, both at the gene and protein levels, and that this modulation depends on the catalytic activity of SphK‐1. Moreover, we determined the effect of sphingosine‐1‐phosphate (S1P), the product of SphK‐1, on P‐gp function. S1P strongly stimulates P‐gp transport activity, without modulating its expression. Finally, we found that the S1P‐mediated stimulation of P‐gp activity is mediated by S1P‐1 and S1P‐3 receptors at the RBE4 cell surface. Altogether, these results indicate that SphK‐1 and its product S1P are involved in the control of P‐gp activity in RBE4 cells. Since SphK‐1 is overexpressed in EC from brain tumors, these data also suggest that this kinase and its product could contribute to the acquisition and the maintenance of the multidrug resistance phenotype in brain tumor‐derived endothelial cells.
Neuroprotective role of bradykinin because of the attenuation of pro‐inflammatory cytokine release from activated microglia
Authors: Noda Mami , Kariura Yukihiro , Pannasch Ulrike , Nishikawa Kaori , Wang Liping , Seike Toshihiro , Ifuku Masataka , Kosai Yuki , Wang Bing , Nolte Christiane , Aoki Shunsuke , Kettenmann Helmut , Wada Keiji 
Published: January 2007

AbstractBradykinin (BK) has been reported to be a mediator of brain damage in acute insults. Receptors for BK have been identified on microglia, the pathologic sensors of the brain. Here, we report that BK attenuated lipopolysaccharide (LPS)‐induced release of tumor necrosis factor‐alpha (TNF‐α) and interleukin‐1β from microglial cells, thus acting as an anti‐inflammatory mediator in the brain. This effect was mimicked by raising intracellular cAMP or stimulating the prostanoid receptors EP2 and EP4, while it was abolished by a cAMP antagonist, a prostanoid receptor antagonist, or by an inhibitor of the inducible cyclooxygenase (cyclooxygenase‐2). BK also enhanced formation of prostaglandin E2and expression of microsomal prostaglandin E synthase. Expression of BK receptors and EP2/EP4 receptors were also enhanced. Using physiological techniques, we identified functional BK receptors not only in culture, but also in microglia from acute brain slices. BK reduced LPS‐induced neuronal death in neuron–microglia co‐cultures. This was probably mediated via microglia as it did not affect TNF‐α‐induced neuronal death in pure neuronal cultures. Our data imply that BK has anti‐inflammatory and neuroprotective effects in the central nervous system by modulating microglial function.
Neuronal NOS‐mediated nitration and inactivation of manganese superoxide dismutase in brain after experimental and human brain injury
Authors: Bayır Hülya , Kagan Valerian E. , Clark Robert S. B. , Janesko‐Feldman Keri , Rafikov Ruslan , Huang Zhentai , Zhang Xiaojing , Vagni Vincent , Billiar Timothy R. , Kochanek Patrick M. 
Published: January 2007

AbstractManganese superoxide dismutase (MnSOD) provides the first line of defense against superoxide generated in mitochondria. SOD competes with nitric oxide for reaction with superoxide and prevents generation of peroxynitrite, a potent oxidant that can modify proteins to form 3‐nitrotyrosine. Thus, sufficient amounts of catalytically competent MnSOD are required to prevent mitochondrial damage. Increased nitrotyrosine immunoreactivity has been reported after traumatic brain injury (TBI); however, the specific protein targets containing modified tyrosine residues and functional consequence of this modification have not been identified. In this study, we show that MnSOD is a target of tyrosine nitration that is associated with a decrease in its enzymatic activity after TBI in mice. Similar findings were obtained in temporal lobe cortical samples obtained from TBI cases versus control patients who died of causes not related to CNS trauma. Increased nitrotyrosine immunoreactivity was detected at 2 h and 24 h versus 72 h after experimental TBI and co‐localized with the neuronal marker NeuN. Inhibition and/or genetic deficiency of neuronal nitric oxide synthase (nNOS) but not endothelial nitric oxide synthase (eNOS) attenuated MnSOD nitration after TBI. At 24 h after TBI, there was predominantly polymorphonuclear leukocytes accumulation in mouse brain whereas macrophages were the predominant inflammatory cell type at 72 h after injury. However, a selective inhibitor or genetic deficiency of inducible nitric oxide synthase (iNOS) failed to affect MnSOD nitration. Nitration of MnSOD is a likely consequence of peroxynitrite within the intracellular milieu of neurons after TBI. Nitration and inactivation of MnSOD could lead to self‐amplification of oxidative stress in the brain progressively enhancing peroxynitrite production and secondary damage.