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691.
692.
Gaze direction is known to be an important factor in regulating social interaction. Recent evidence suggests that direct and averted gaze can signal the sender's motivational tendencies of approach and avoidance, respectively. We aimed at determining whether seeing another person's direct vs. averted gaze has an influence on the observer's neural approach-avoidance responses. We also examined whether it would make a difference if the participants were looking at the face of a real person or a picture. Measurements of hemispheric asymmetry in the frontal electroencephalographic activity indicated that another person's direct gaze elicited a relative left-sided frontal EEG activation (indicative of a tendency to approach), whereas averted gaze activated right-sided asymmetry (indicative of avoidance). Skin conductance responses were larger to faces than to control objects and to direct relative to averted gaze, indicating that faces, in general, and faces with direct gaze, in particular, elicited more intense autonomic activation and strength of the motivational tendencies than did control stimuli. Gaze direction also influenced subjective ratings of emotional arousal and valence. However, all these effects were observed only when participants were facing a real person, not when looking at a picture of a face. This finding was suggested to be due to the motivational responses to gaze direction being activated in the context of enhanced self-awareness by the presence of another person. The present results, thus, provide direct evidence that eye contact and gaze aversion between two persons influence the neural mechanisms regulating basic motivational-emotional responses and differentially activate the motivational approach-avoidance brain systems.  相似文献   
693.
Alterations in the immune system may have importance for the pathophysiology of depression. Several studies have linked increased production of pro-inflammatory cytokines to depression and depressive symptoms. There is growing evidence that antidepressive treatment may influence the production of pro-and anti-inflammatory cytokines. In the present study we aimed to find associations between the levels of soluble interleukin-2 receptor (sIL-2R), interleukin-8 (IL-8) and tumor necrosis factor alpha (TNF-alpha) and the response to antidepressant treatment in patients with major depression. Our study group consisted of 100 patients (35 males and 65 females) who were treated with escitalopram 10-20 mg/day for 12 weeks. Responders and non-responders were identified according to Montgomery-Asberg's Depression Rating Scale (MADRS) scores. The levels of cytokines were measured at baseline and at 4th and 12th week of the treatment and compared to cytokine concentrations in healthy volunteers (n=45; 19 males and 26 females). Our data indicated that a higher level of TNF-alpha might predict a non-response to treatment with escitalopram and that changes in concentrations of sIL-2R during the treatment were different in responders and non-responders.  相似文献   
694.
A specific learning disability, developmental dyslexia, is a language-based disorder that is shown to be strongly familial. Therefore, infants born to families with a history of the disorder are at an elevated risk for the disorder. However, little is known of the potential early markers of dyslexia. Here we report differences between 6-month-old infants with and without high risk of familial dyslexia in brain electrical activation generated by changes in the temporal structure of speech sounds, a critical cueing feature in speech. We measured event-related brain responses to consonant duration changes embedded in ata pseudowords applying an oddball paradigm, in which pseudoword tokens with varying /t/ duration were presented as frequent standard (80%) or as rare deviant stimuli (each 10%) with an interval of 610 msec between the stimuli. The infants at risk differ from control infants in both their initial responsiveness to sounds per se and in their change-detection responses dependent on the stimulus context. These results show that infants at risk due to a familial background of reading problems process auditory temporal cues of speech sounds differently from infants without such a risk even before they learn to speak.  相似文献   
695.
Mitogen-activated protein kinase phosphatase-1 (MKP-1) is a nuclear tyrosine/threonine phosphatase that inhibits p38 mitogen-activated protein kinase (MAPK) activity. We and others have shown that MKP-1 deficiency leads to excessive activation of innate immunity and inflammatory gene expression. Surprisingly, the present study shows that MKP-1 is a positive regulator of IL-12 expression in macrophages suggesting a stimulatory effect on Th1 type immune response. In the present study, we found that LPS-induced expression of IL-12p40 was lower in primary mouse peritoneal macrophages (PMs) and bone marrow-derived macrophages from MKP-1 deficient mice than in cells from wild-type mice whereas TNF expression was enhanced as expected. Correspondingly, the inhibition of p38 MAPK by pharmacologic inhibitors BIRB 796 and SB 202190 enhanced LPS-induced IL-12p40 production. Silencing of interferon regulatory factor 1 (IRF1) by siRNA inhibited the expression of IL-12p40 in J774 macrophages, showing that IRF1 is an important factor regulating IL-12p40 expression. BIRB 796 enhanced LPS-induced expression of IRF1 in J774 macrophages and in PMs from wild-type mice, and IRF1 expression was reduced in PMs from MKP-1 deficient mice. In conclusions, our results show that MKP-1 increases and p38 MAPK decreases the expression of IL-12 by enhancing the expression of IRF1. MKP-1, through regulation of IRF1 and IL-12, therefore may be an important factor supporting the development of Th1 type of immune response and anti-microbial defense.  相似文献   
696.
Germinal center (GC) and non-GC phenotypes are predictors of outcome in diffuse large B-cell lymphoma (DLBCL) and can be used to stratify chemotherapy-treated patients into low- and high-risk groups. To determine how combination of rituximab with chemotherapy influences GC-associated clinical outcome, GC and non-GC phenotypes were identified immunohistochemically from samples of 90 de novo DLBCL patients treated with rituximab in combination with CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone)-like regimen (immunochemotherapy). One hundred and four patients previously treated with chemotherapy served as a control group. Consistent with previous studies, chemotherapy-treated patients with immunohistochemically defined GC phenotype displayed a significantly better overall (OS) and failure-free survival (FFS) than the non-GC group (OS, 70% vs 47%, P = .012; FFS, 59% vs 30%, P = .001). In contrast, immunohistochemically defined GC phenotype did not predict outcome in immunochemotherapy-treated patients (OS, 77% vs 76%, P = ns; FFS, 68% vs 63%, P = ns). In comparison, International Prognostic Index (IPI) could separate the high-risk patients from low- and intermediate-risk groups (OS, 84% vs 63%, P = .030; FFS, 79% vs 52%, P = .028). We conclude that rituximab in combination with chemotherapy seems to eliminate the prognostic value of immunohistochemically defined GC- and non-GC phenotypes in DLBCL.  相似文献   
697.
OBJECTIVE: To evaluate functioning and preferences for health among young adult patients with juvenile idiopathic arthritis (JIA) and controls. The WHO International Classification of Functioning, Disability and Health (ICF) was used as a framework. METHODS: The patient files of a rheumatology hospital were screened to identify patients with juvenile arthritis born 1976 to 1980. Functioning was measured by the Finnish version of the Multidimensional Health Assessment Questionnaire (MDHAQ) within the framework of the ICF. Preferences in improvement of health were measured by the Finnish version of the Arthritis Impact Measurement Scales 2. Age and sex matched controls from the community were selected from the Finnish population registry. RESULTS: In all, 123 patients with a mean age of 23 (SD 21-26) years participated in the followup study. The mean time from diagnosis to followup was 16.2 years. Among them, 35% (n = 43) were in remission at followup. Lower levels of functioning for 3 ICF components were found in patients with active disease compared to controls. JIA patients with active disease had more pain and lower levels of mobility, self-care, and domestic and social life compared to controls. Patients with active disease differed from those in remission with pain in preferences for improvement of health. CONCLUSION: Patients with active disease need active treatment and rehabilitation to maintain functioning and decrease pain. The ICF offers a promising model to examine the outcomes of adult patients with JIA. Application of the MDHAQ is supported by our evaluation studies in young adults with JIA.  相似文献   
698.
In this study, GNF@ZnO composites (gelatin nanofibers (GNF) with zinc oxide (ZnO) nanoparticles (NPs)) as a novel antibacterial agent were obtained using a wet chemistry approach. The physicochemical characterization of ZnO nanoparticles (NPs) and GNF@ZnO composites, as well as the evaluation of their antibacterial activity toward Gram-positive (Staphyloccocus aureus and Bacillus pumilus) and Gram-negative (Escherichia coli and Pseudomonas fluorescens) bacteria were performed. ZnO NPs were synthesized using a facile sol-gel approach. Gelatin nanofibers (GNF) were obtained by an electrospinning technique. GNF@ZnO composites were obtained by adding previously produced GNF into a Zn2+ methanol solution during ZnO NPs synthesis. Crystal structure, phase, and elemental compositions, morphology, as well as photoluminescent properties of pristine ZnO NPs, pristine GNF, and GNF@ZnO composites were characterized using powder X-ray diffraction (XRD), FTIR analysis, transmission and scanning electron microscopies (TEM/SEM), and photoluminescence spectroscopy. SEM, EDX, as well as FTIR analyses, confirmed the adsorption of ZnO NPs on the GNF surface. The pristine ZnO NPs were highly crystalline and monodispersed with a size of approximately 7 nm and had a high surface area (83 m2/g). The thickness of the pristine gelatin nanofiber was around 1 µm. The antibacterial properties of GNF@ZnO composites were investigated by a disk diffusion assay on agar plates. Results show that both pristine ZnO NPs and their GNF-based composites have the strongest antibacterial properties against Pseudomonas fluorescence and Staphylococcus aureus, with the zone of inhibition above 10 mm. Right behind them is Escherichia coli with slightly less inhibition of bacterial growth. These properties of GNF@ZnO composites suggest their suitability for a range of antimicrobial uses, such as in the food industry or in biomedical applications.  相似文献   
699.
Daily patterns of pineal function were studied in different seasons in 10 adult semidomesticated female reindeer and 5 prepubertal calves living in a natural arctic environment at latitude 69 degrees 10'N. Serum samples for melatonin RIA were collected every 4 h for 24 h in October (10 h of light, 14 h of darkness and 8 h of light, 16 h of darkness), December (24 h of darkness), March (13 h of light, 11 h of darkness), and June (24 h of light). A significant daily variation in serum melatonin levels was observed in the adult reindeer, with peak values (20-50 ng/liter) occurring during the night in autumn, winter, and spring, but not summer. The daytime values at 13 h (5-10 ng/liter) were constant throughout the year. Total daily amounts of melatonin, the duration of peak levels, and maximal concentrations were significantly lower in spring and summer than before the rut in autumn. The exposure of adult animals to artificial darkness from bright sunlight on August 1 and September 21 resulted in an immediate increase in serum melatonin concentrations. The 2-week-old calves had detectable serum melatonin levels, but no daily rhythm in the spring, whereas a rhythm was detectable by the first autumn, only to disappear unexpectedly during the first winter and return in the spring. At the age of 16 months, the calves had serum melatonin concentrations similar to those in the adults. Our present results show that the continuous illumination experienced during the summer abolished the normal daily melatonin rhythm. This does not seem to be related to organic changes in the pineal gland, since exposure to darkness during the summer increased melatonin levels. The highest melatonin secretion occurred in the autumn and was evidently associated with the rut. Similarly, the daily melatonin rhythm of an adult type observed in the calves at the age of 16 months may be related to the observation that most calves were in rut. Thus, a high rhythmical melatonin secretion appears to relate to puberty and the initiation of heat in female reindeer.  相似文献   
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