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71.
72.
The KIR locus with genes involved in immune processes is among the most polymorphic and structurally diverse human loci. KIR genes encode activating and inhibitory receptors that differ in specificity for HLA class I ligands and signaling potential. These receptors are expressed principally by natural killer (NK) cells and subpopulations of T cells. This study represents the first report of the distribution of KIR genes, KIR genotypes and KIR/HLA pairs in 121 unrelated healthy Croatian individuals. Twenty-three different genotypes were observed in the Croatian population and all 16 KIR genes known to date were found. The most frequent KIR genotype was the AA genotype. All individuals had at least one inhibitory KIR/HLA pair with the majority of individuals with three inhibitory KIR/HLA pairs. The most frequent KIR/HLA pair was the KIR2DL3/C1 group. Our results demonstrated the similarity of the Croatian population’s KIR repertoire with other Caucasian populations reported so far.  相似文献   
73.
The event-related responses of 18 individuals were recorded while they were listening to 3 music clips of 6 s duration which were repeated 30 times each. The music clips differed in the level of their complex structure, induced mood, musical tempo and prominent frequency. They were taken from Mozart's sonata (K. 448), and Brahms' Hungarian dance (no. 5). The third clip was a simplified version of the theme taken from Haydn's symphony (no. 94) played by a computer synthesizer. Significant differences in induced event-related desynchronization between the 3 music clips were only observed in the lower-1 alpha band which is related to attentional processes. A similar pattern was observed for the coherence measures. While respondents listened to the Mozart clip, coherence in the lower alpha bands increased more, whereas in the gamma band a less pronounced increase was observed as compared with the Brahms and Haydn clips. The clustering of the three clips based on EEG measures distinguished between the Mozart clip on the one hand, and the Haydn and Brahms clips on the other, even though the Haydn and Brahms clips were at the opposite extremes with regard to the mood they induced in listeners, musical tempo, and complexity of structure. This would suggest that Mozart's music--with no regard to the level of induced mood, musical tempo and complexity--influences the level of arousal. It seems that modulations in the frequency domain of Mozart's sonata have the greatest influence on the reported neurophysiological activity.  相似文献   
74.
BACKGROUND: The Bipolar Comprehensive Outcomes Study (BCOS) is a 2-year, observational study of participants with bipolar I or schizoaffective disorder examining clinical, functional, and economic outcomes associated with naturalistic treatment. METHODS: Participants prescribed mood stabilisers were assessed using various measures, including the Young Mania Rating Scale (YMRS), 21-item Hamilton Depression Rating scale (HAMD21), Clinical Global Impressions-Bipolar Version Severity of Illness scale (CGI-BP), and the EuroQol instrument (EQ-5D). RESULTS: 240 participants were recruited from two sites. On average, participants were 41.8+/-12.7 years of age (mean+/-SD), 58.3% were female, and 73.3% had a diagnosis of bipolar I disorder at study entry. The majority of participants were moderately ill, with an average CGI-BP Overall score of 3.8+/-1.3. Most participants had subthreshold mania and depression symptoms, indicated by HAMD21 Total 13.4+/-8.6, CGI-BP Depression 3.2+/-1.3, YMRS Total 8.2+/-8.5 and CGI-BP Mania 3.0+/-1.6 average scores. For bipolar participants, 94.6% of hospitalisations for psychiatric treatment in the past 3 months were single admissions (vs. 65.2% for schizoaffective participants, p=.002). Bipolar participants rated their overall health state higher (EQ-5D scores: 68.2+/-18.8 vs. 61.6+/-22.7, p=.023), had a higher mean weekly wage ($500-$999, 21.3% vs. 6.3%), lower unemployment (22.2% vs. 48.4%), and higher romantic relationship status (47.1% vs. 26.6%). LIMITATIONS: The observational design and small sample size may have limited the causal relationships and generalisability within the current findings. CONCLUSIONS: Participants were characterised by social and occupational dysfunction at entry, but schizoaffective participants appeared to be more severely affected. Effective treatment is required to address both clinical and functional impairment.  相似文献   
75.
76.
Derivation of a xeno-free human embryonic stem cell line   总被引:7,自引:0,他引:7  
Elimination of all animal material during both the derivation and long-term culture of human embryonic stem cells (hESCs) is necessary prior to future application of hESCs in clinical cell therapy. The potential consequences of transplanting xeno-contaminated hESCs into patients, such as an increased risk of graft rejection [Stem Cells 2006; 24:221-229] and the potential transfer of nonhuman pathogens, make existing hESC lines unsuitable for clinical applications. To avoid xeno-contamination during derivation and culture of hESCs, we first developed a xeno-free medium supplemented with human serum, which supports long-term (>50 passages) culture of hESCs in an undifferentiated state. To enable derivation of new xeno-free hESCs, we also established xeno-free human foreskin fibroblast feeders and replaced immunosurgery, which involves the use of guinea pig complement, with a modified animal-product-free derivation procedure. Here, we report the establishment and characterization (>20 passages) of a xeno-free pluripotent diploid normal hESC line, SA611.  相似文献   
77.
Interaction between autoreactive immune cells and astroglia is an important part of the pathologic processes that fuel neurodegeneration in multiple sclerosis. In this inflammatory disease, immune cells enter into the central nervous system (CNS) and they spread through CNS parenchyma, but the impact of these autoreactive immune cells on the activity pattern of astrocytes has not been defined. By exploiting naïve astrocytes in culture and CNS-infiltrated immune cells (CNS IICs) isolated from rat with experimental autoimmune encephalomyelitis (EAE), here we demonstrate previously unrecognized properties of immune cell–astrocyte interaction. We show that CNS IICs but not the peripheral immune cell application, evokes a rapid and vigorous intracellular Ca2+ increase in astrocytes by promoting glial release of ATP. ATP propagated Ca2+ elevation through glial purinergic P2X7 receptor activation by the hemichannel-dependent nucleotide release mechanism. Astrocyte Ca2+ increase is specifically triggered by the autoreactive CD4+ T-cell application and these two cell types exhibit close spatial interaction in EAE. Therefore, Ca2+ signals may mediate a rapid astroglial response to the autoreactive immune cells in their local environment. This property of immune cell–astrocyte interaction may be important to consider in studies interrogating CNS autoimmune disease.  相似文献   
78.
Synaptic vesicle glycoprotein 2A (SV2A) has been previously characterized as an imaging biomarker for assessment of synaptic density in positron emission tomography (PET) studies of patients with neurological conditions. To provide detailed maps of the brain localization of SV2A autoradiography studies were carried out using the SV2A radioligand [11C]UCB-J and whole hemisphere sections of non-human primate (NHP) and human brain. Binding of [11C]UCB-J was observed in all evaluated grey matter structures of the primate brain, with highest density in the caudate nucleus and cortex and lowest density in pons and globus pallidus. The density of [11C]UCB-J binding sites in human brain showed a good correlation with that in NHP brain. Binding of [11C]UCB-J in the white matter was very low relative to that in grey matter containing structures and was only inhibited to a minor extent by co-incubation with a saturating concentration of unlabelled UCB-J. The high-resolution images obtained in the present study may aid the interpretation of data acquired in human subjects examined using [11C]UCB-J in PET studies. In addition, observation of low binding for [11C]UCB-J in white matter (centrum semiovale) supports that this structure can be used as a reference region for quantitative analysis of [11C]UCB-J PET data.  相似文献   
79.
80.
Alzheimer's disease (AD) involves selective loss of basal forebrain cholinergic neurons, particularly in the nucleus basalis (NB). Similarly, Parkinson's disease (PD) might involve the selective loss of pedunculopontine tegmental nucleus (PPT) cholinergic neurons. Therefore, lesions of these functionally distinct cholinergic centers in rats might serve as models of AD and PD cholinergic neuropathologies. Our previous articles described dissimilar sleep/wake‐state disorders in rat models of AD and PD cholinergic neuropathologies. This study further examines astroglial and microglial responses as underlying pathologies in these distinct sleep disorders. Unilateral lesions of the NB or the PPT were induced with rats under ketamine/diazepam anesthesia (50 mg/kg i.p.) by using stereotaxically guided microinfusion of the excitotoxin ibotenic acid (IBO). Twenty‐one days after the lesion, loss of cholinergic neurons was quantified by nicotinamide adenine dinucleotide phosphate‐diaphorase histochemistry, and the astroglial and microglial responses were quantified by glia fibrillary acidic protein/OX42 immunohistochemistry. This study demonstrates, for the first time, the anatomofunctionally related astroglial response following unilateral excitotoxic PPT cholinergic neuronal lesion. Whereas IBO NB and PPT lesions similarly enhanced local astroglial and microglial responses, astrogliosis in the PPT was followed by a remote astrogliosis within the ipslilateral NB. Conversely, there was no microglial response within the NB after PPT lesions. Our results reveal the rostrorostral PPT‐NB astrogliosis after denervation of cholinergic neurons in the PPT. This hierarchically and anatomofunctionally guided PPT‐NB astrogliosis emerged following cholinergic neuronal loss greater than 17% throughout the overall rostrocaudal PPT dimension. © 2014 Wiley Periodicals, Inc.  相似文献   
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