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991.
Lack of association with the CD28/CTLA4/ICOS gene region among Norwegian multiple sclerosis patients
Lorentzen AR Celius EG Ekstrøm PO Wiencke K Lie BA Myhr KM Ling V Thorsby E Vartdal F Spurkland A Harbo HF 《Journal of neuroimmunology》2005,166(1-2):197-201
Chromosome region 2q33 encodes several regulators of the immune system, among these the CD28, CTLA4, and ICOS molecules. Involvement of these genes in multiple sclerosis (MS) is not yet clear. We investigated six microsatellites and three SNPs in a relatively large and clinically well characterised Norwegian MS cohort. No associations were observed for any of the markers analysed in 575 MS patients and 551 controls. Associations were neither found when stratifying the material for the HLA-DRB1*1501, DQB1*0602 haplotype, gender, age at onset, disease course nor familial aggregation. In conclusion, this study could not confirm association with the CD28/CTLA4/ICOS gene region. 相似文献
992.
Argumentation with restricted linguistic ability: performing a role play with aphasia or in a second language 总被引:1,自引:0,他引:1
Ahlsén E 《Clinical linguistics & phonetics》2005,19(5):433-451
The main objective of this study is to illustrate how adaptation to linguistic limitations takes place in a specific activity and is affected by factors pertaining to the social activity or the individuals. A man with aphasia is compared to an adult immigrant L2 learner. An argumentative role play was video-recorded, transcribed and analysed. Both subjects have a very limited vocabulary and produce short utterances. The L2 learner often uses words that are semantically related to the target word, while the subject with aphasia uses more general and vague words, like pronouns, in combination with adverbs and set phrases. Both subjects use gesturing as strategy, and it is suggested that the semantic specificity of words as well as gestures is important in determining the role of gesture. Apart from gesture, he L2 learner uses mainly simplification and appeal strategies, while the subject with aphasia uses mainly fluency and sociolinguistic strategies. 相似文献
993.
Besides its pivotal role in reproduction, the polypeptide hormone prolactin (PRL) has immunomodulatory properties. Whereas the bulk of circulating PRL is produced by the pituitary, PRL is also produced by the decidua, the myometrium, the mammary gland and leukocytes. Extrapituitary PRL expression is regulated differently from that in the pituitary, due to the use of an alternative promoter. Here we show for the first time that in T lymphocytes PRL expression is subject to regulation by cytokines. We established that both IL-2 and IL-4 reduced PRL mRNA levels in T lymphocytes to 25 and 28% of control values, respectively. PRL mRNA expression was inhibited to a lesser extent by IL-1beta, which decreased PRL mRNA levels to 58% of control values. 相似文献
994.
Evidence implies that nitric oxide (NO) in the central nervous systems mediates anorexia in tumor-bearing hosts. We have therefore evaluated, by immunohistochemical image analyses, net alterations of nitric oxide synthases (nNOS, eNOS, iNOS) in brain nuclei [paraventricular hypothalamic nucleus (PVN), medial habenular nucleus (MHB), lateral habenular nucleus (LHB), paraventricular thalamic nucleus (PV), lateral hypothalamic area (LHA), ventromedial hypothalamic nucleus (VMH), nucleus of the solitary tract (NTS)] of tumor-bearing mice (TB) with prostanoid-related anorexia. Pair-fed (PF) and freely fed (FF) non-tumor-bearing mice were used as controls. c-fos was analyzed as indicator of neuronal activation. nNOS was significantly increased in VMH and PVN from TB mice, while eNOS was significantly increased in LHB and LHA. iNOS was significantly increased in LHA and PVN nuclei, but decreased in MHB, LHB and VMH from tumor-bearers. However, several of these alterations were similarly observed in brain nuclei from pair-fed controls. Provision of unspecific NOS-antagonists to TB mice increased nNOS, eNOS and iNOS in several brain nuclei (PVN, LHA, VMH), but left tumor-induced anorexia unchanged. c-fos was significantly increased in all brain nuclei in PF mice except for NTS, LHA and PVN compared to controls, while tumor-bearing mice had increased c-fos in LHA and PVN only compared to controls. Our results demonstrate a complex picture of NOS expression in brain areas of relevance for appetite in tumor-bearing hosts, where most changes seemed to be secondary to stress during negative energy balance. By contrast, NOS content in PVN and LHA nuclei remains candidate behind anorexia in tumor disease. However, nitric oxide does not seem to be a primary mediator behind tumor-induced anorexia. NO may rather secondarily support energy intake in conditions with negative energy balance. 相似文献
995.
Barden N Shink E Labbé M Vacher R Rochford J Mocaër E 《Progress in neuro-psychopharmacology & biological psychiatry》2005,29(6):908-916
The aim of this study was to evaluate the efficacy of agomelatine (S 20098) to accelerate reversal of the neuroendocrinological, behavioural and cyclical changes seen in a transgenic mouse model of the neuroendocrine characteristics of depression. The effects of agomelatine were assessed in transgenic mice with low glucocorticoid receptor (GR) function, after acute stress or induced phase shift, and compared to desipramine and melatonin. Mice were injected 2 h before the onset of the dark period with agomelatine (10 mg/kg, i.p.), desipramine (10 mg/kg, i.p.), melatonin (10 mg/kg, i.p.) or vehicle (hydroxy-ethyl-cellulose (HEC) 1%) each day for 21 to 42 days. Agomelatine was effective in reversing the transgenic mouse behavioural changes noted in the Porsolt forced swim test as well as in the elevated plus maze. Both the number of open arm entries and the total time spent in open arms of the elevated plus maze is greatly increased in transgenic mice. The mean time spent in open arms is exquisitely sensitive to reversal by agomelatine and desipramine. Agomelatine also markedly accelerated readjustment of circadian cycles of temperature and activity following an induced phase shift. This action of agomelatine was superior to that of melatonin while desipramine was without effect. The accelerating effect of agomelatine was particularly notable if treatment was started 3 weeks prior to the induced phase shift. Agomelatine treatment did not cause any major change in corticosterone or adrenocorticotropic hormone (ACTH) concentrations nor in vasopressin (AVP), corticotropin-releasing hormone (CRH), GR and mineralocorticoid receptor (MR) mRNAs levels, which make it unlikely that the mechanism of agomelatine action is related to hypothalamic-pituitary-adrenocortical (HPA) axis changes. The present study shows that agomelatine displays some characteristics of antidepressant drug action in the transgenic mouse model, effects that could be partially related to its chronobiotic properties. 相似文献
996.
Tirado I Mateo J Soria JM Oliver A Martínez-Sánchez E Vallvé C Borrell M Urrutia T Fontcuberta J 《Thrombosis and haemostasis》2005,93(3):468-474
Factor VIII (FVIII), von Willebrand factor (vWF) and the ABO blood groups have been associated with thrombosis. The ABO locus has functional effects on vWF and FVIII levels and is genetically correlated with FVIII, vWF and thrombosis. We carried out a case-control study to assess the role of FVIII, vWF and ABO types on thrombotic risk. We analyzed 250 patients with venous thrombosis and 250 unrelated controls. FVIII, vWF and other factors related to thrombophilia were measured, ABO groups were analyzed by genotyping. FVIII and vWF were higher in non-O individuals. Group O was more frequent in the controls (44.3% v 23.3%; difference 21.1%; 95% CI: 13.0-29.3%) and Group A in patients (59.2% v. 41.5%; difference 17.7%, 95% CI: 9.1-26.4%). Individuals carrying the A1 allele had a higher risk of thrombosis (OR 2.6; 95% CI, 1.8-3.8). The risk attributed to vWF disappeared after adjusting for the ABO group. Patients with FVIII above the 90th percentile had a high thrombotic risk (adjusted OR 3.7; 95% CI, 2.1-6.5), and a high risk of recurrence (OR 2.3; 95% CI: 1.3-4.1). In conclusion, high FVIII levels and non-O blood groups, likely those with the A1 allele, are independent risk factors for venous thromboembolism and should be considered in evaluating of thrombophilia. 相似文献
997.
998.
Clinical and magnetic resonance imaging characteristics of sporadic cerebellar ataxia 总被引:2,自引:0,他引:2
Bürk K Bühring U Schulz JB Zühlke C Hellenbroich Y Dichgans J 《Archives of neurology》2005,62(6):981-985
BACKGROUND: It is unknown whether multiple system atrophy of the cerebellar type (MSA-C) and idiopathic cerebellar ataxia with extracerebellar presentation (IDCA-P) represent distinct entities. OBJECTIVE: To investigate the discriminative validity of magnetic resonance imaging in sporadic cerebellar ataxia. DESIGN: Basal ganglia and infratentorial structures were screened for signal abnormalities and atrophic changes. Magnetic resonance imaging raters were masked to the clinical diagnosis. SETTING: Outpatient clinic of a university hospital. PATIENTS: Forty-one individuals were diagnosed as having MSA-C (n = 30) or IDCA-P (n = 11) based on their clinical features. RESULTS: Shrinkage of the cerebellar vermis and hemispheres was found in both groups. Atrophy of the brainstem and middle cerebellar peduncles was significantly more frequent in patients with MSA-C (P<.001). Hyperintensities of infratentorial structures were common in patients with MSA-C (middle cerebellar peduncles: 87%; pons: 97%) but were absent in patients with IDCA-P. Hypointensities or hyperintensities of basal ganglia structures did not reliably differentiate the groups. CONCLUSIONS: Patients with MSA-C were characterized by a higher frequency and severity of magnetic resonance imaging abnormalities (atrophic changes and additional hyperintense signal changes) of the middle cerebellar peduncles and pons. The presence of these magnetic resonance imaging features points to the diagnosis of MSA-C and helps differentiate MSA-C from other types of sporadic cerebellar ataxia with extracerebellar features. 相似文献
999.
A population of embryonic rat cortical cells cultured in the presence of FGF2 and having neuronal morphology expressed higher levels of reactive oxygen species (ROS) than did progenitor cells, astrocytes, and several cell lines of neuronal and non-neuronal origin. ROS were assessed using 5-(and-6)-chlormethyl-2',7'-dichlorodihydrofluorescein diacetate, acetyl ester (CM-H2DCF-DA), and high levels persisted in the presence of antioxidants or lowered levels of ambient oxygen. Greater than 95% of high ROS-producing cells, isolated by fluorescence-activated cell sorting, expressed the neuronal marker beta III tubulin. These cells did not incorporate BrdU or express nestin, unlike low ROS-producing cells, 99% of which exhibited both of these characteristics. Upon growth factor removal, low ROS-expressing cells differentiated into neurons and astrocytes and these neurons expressed high levels of ROS, indicating that ROS accumulation accompanies the differentiation of progenitors into neurons. ROS levels were decreased by added superoxide dismutase and catalase, suggesting that both superoxide and hydrogen peroxide contribute to the ROS signal. High ROS-expressing cells also contained higher levels of several mitochondrial respiratory chain components. Although ROS have been associated with conditions that lead to cell death, our results and recent studies on the role of ROS as regulators of signal pathways are consistent with the possibility that ROS play a role in the development of the neuronal phenotype. Moreover, the differential production of ROS provides a useful method to isolate from mixed populations cells that are highly enriched for either progenitor cells or neurons. 相似文献
1000.
In this two-part study, we assessed musical involvements in two samples of persons with Williams syndrome compared to others with mental retardation and also related musicality to anxiety and fears in Study 2. Relative to others with mental retardation, those with Williams syndrome were more likely to take music lessons, play an instrument, and have higher ratings of musical skills. In the Williams syndrome groups only, fewer externalizing symptoms were associated with listening to music, whereas less anxiety and fewer fears were associated with the frequency, duration, and skill in producing music as well as emotional responses to negatively toned music. Implications are discussed for future research on musical processing, musical interventions, and well-being in Williams syndrome and other groups. 相似文献