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51.
Kopp MV Brauburger J Riedinger F Beischer D Ihorst G Kamin W Zielen S Bez Friedrichs F Von Berg A Gerhold K Hamelmann E Hultsch Kuehr J 《The Journal of allergy and clinical immunology》2002,110(5):728-735
BACKGROUND: Binding of allergens with IgE to the IgE receptors on mast cells and basophils results in the release of inflammatory mediators as sulfidoleukotrienes (SLTs), triggering allergic cascades that result in allergic symptoms, such as asthma and rhinitis. OBJECTIVE: We sought to investigate whether anti-IgE (Oma-lizumab), a humanized monoclonal anti-IgE antibody, in addition to specific immunotherapy (SIT) affects the leukotriene pathway. METHODS: Ninety-two children (age range, 6-17 years) with sensitization to birch and grass pollens and with seasonal allergic rhinitis were included in a phase III, placebo- controlled, multicenter clinical study. All subjects were randomized to one of 4 treatment groups. Two groups subcutaneously received birch SIT and 2 groups received grass SIT for at least 14 weeks before the start of the birch pollen season. After 12 weeks of SIT titration, placebo or anti-IgE was added for 24 weeks. The primary clinical efficacy variable was symptom load (ie, the sum of daily symptom severity score and rescue medication score during pollen season). Blood samples taken at baseline and at the end of study treatment after the grass pollen season were used for separation of leukocytes in this substudy. After in vitro stimulation of the blood cells with grass and birch pollen allergens, SLT release (LTC4, LTD4, and LTE4) was quantified by using the ELISA technique. RESULTS: Before the study treatment, SLT release to birch and grass pollen exposure did not differ significantly among the 4 groups. Under treatment with anti-IgE + SIT-grass (n = 23), a lower symptom load occurred during the pollen season compared to placebo + SIT-grass (n = 24, P =.012). The same applied to both groups receiving birch SIT (n = 23 and n = 22, respectively; P =.03). At the end of treatment, the combination of anti-IgE plus grass SIT, as well as anti-IgE plus birch SIT, resulted in significantly lower SLT release after stimulation with the corresponding allergen (416 ng/L [5th-95th percentile, 1-1168] and 207 ng/L [1-860 ng/L], respectively) compared with placebo plus SIT (2490 ng/L [384-6587 ng/L], P =.001; 2489 ng/L [1-5670 ng/L], P =.001). In addition, treatment with anti-IgE was also followed by significantly lower SLT releases to the allergens unrelated to SIT (grass SIT: 300 ng/L [1-2432 ng/L] in response to birch allergen; birch SIT: 1478 ng/L [1-4593 ng/L] in response to grass pollen) in comparison with placebo (grass SIT: 1850 ng/L [1-5499 ng/L], P =.001; birch SIT: 2792 ng/L [154-5839 ng/L], P =.04]. CONCLUSION: Anti-IgE therapy reduces leukotriene release of peripheral leukocytes stimulated with allergen in children with allergic rhinitis undergoing allergen immunotherapy independent of the type of SIT allergen used. 相似文献
52.
A new method to assess attachment representations in children by applying a story completion procedure in doll play (SCPDP) is presented. Transmission and continuity of attachment were tested in 28 German families by using the Strange Situation procedure (SS) with the mother and her infant, the Adult Attachment Interview (AAI) with the mother when the child is 5 years old, and the attachment representations (SCPDP) of the 6-year-olds. Relying on the twofold distinction (secure/insecure), results revealed a significant continuity of attachment from 1 to 6 years of age, and a correspondence between maternal AAI and child's attachment quality in SS, as well as a correspondence between maternal AAI and the 6-year-olds' attachment representations. Using configural frequency analysis, we found continuity in patterns of security and insecurity when looking across the measures of infant and pre-school attachment and maternal adult attachment. Processes underlying the high match of mothers' and children's attachment representations are discussed. 相似文献
53.
Calorini L Mannini A Bianchini F Mugnai G Balzi M Becciolini A Ruggieri S 《Clinical & experimental metastasis》1999,17(10):889-895
A previous study by our laboratory showed that the peritoneal murine Corynebacterium parvum-elicited macrophages released into their growth medium an activity which enhanced the ability of B16-F10 melanoma cells to
form experimental metastases in the lung of syngeneic mice. In the present study, we used a clone of B16-F10 line (F10-M3
cells) to investigate whether the increase in lung-colonizing potential due to the pro-clonogenic activity released by C. parvum-elicited macrophages was associated with biological properties characteristic of a metastatic phenotype. We have found that
the pulmonary retention, growth rate in lung parenchyma, invasiveness through Matrigel, adhesiveness to IL-1-activated endothelium
and MHC class I expression were increased in F10-M3 cells stimulated by the macrophage pro-clonogenic activity. By using an
in vitro experimental protocol, the enhancement of lung-colonizing potential in the stimulated melanoma cells turned out to be a transient
phenomenon as was the increase of invasiveness through Matrigel and the higher expression of MHC class I antigens. In conclusion,
the melanoma cells stimulated by the pro-clonogenic activity released by C. parvum-elicited macrophages showed changes in biological parameters which are relevant to metastatic diffusion. These changes appeared
as a temporary phenomenon which sustains the view that the metastatic phenotype represents a transient biological character
influenced by host factors.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
54.
Làdavas E Farnè A Zeloni G di Pellegrino G 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2000,131(4):458-467
Previous findings have demonstrated the existence of a visual peripersonal space centered on the hand in humans and its modulatory effects on tactile perception. A strong modulatory effect of vision on touch perception was found when a visual stimulus was presented near the hand. In contrast, when the visual stimulus was presented far from the hand, only a weak modulatory effect was found. The aim of the present study was to verify whether such cross-modal links between touch and vision in the peripersonal space centered on the hand could be mediated by proprioceptive signals specifying the current hand positions or if they directly reflect an interaction between two sensory modalities, i.e., vision and touch. To this aim, cross-modal effects were studied in two different experiments: one in which patients could see their hands and one in which vision of their hands was prevented. The results showed strong modulatory effects of vision on touch perception when the visual stimulus was presented near the seen hand and only mild effects when the vision of the hand was prevented. These findings are explained by referring to the activity of bimodal neurons in premotor and parietal cortex of macaque, which have tactile receptive fields on the hand, and corresponding visual receptive fields in the space immediately adjacent to the tactile fields. One important feature of these bimodal neurons is that their responsiveness to visual stimuli delivered near the body part is reduced or even extinguished when the view of the body part is prevented. This implies that, at least for the hand, the vision of the hand is crucial for determining the spatial mapping between vision and touch that takes place in the peripersonal space. In contrast, the proprioceptive signals specifying the current hand position in space do not seem to be relevant in determining the cross-modal interaction between vision and touch. 相似文献
55.
Simulation Studies of Latency Measures of Components of the Event-Related Brain Potential 总被引:1,自引:0,他引:1
Gabriele Gratton Arthur F. Kramer Michael G.H. Coles Emanuel Donchin 《Psychophysiology》1989,26(2):233-248
We compared the accuracy of P300 latency estimates obtained with different procedures under several simulated signal and noise conditions. Both preparatory and signal detection techniques were used. Preparatory techniques included frequency filters and spatial filters (single electrode selection and Vector filter). Signal detection techniques included peak-picking, cross-correlation, and Woody filter. Accuracy in the latency estimation increased exponentially as a function of the signal-to-noise ratio. Both Woody filter and cross-correlation provided better estimates than peak-picking, although this advantage was reduced by frequency filtering. For all signal detection techniques, Vector filter provided better estimates than single electrode selection. Large component overlap impaired the accuracy of the estimates obtained with both single electrode selection and Vector filter, but with Vector filter impairment occurred only when the overlapping component had a scalp distribution that was similar to the scalp distribution of the signal component. The effects of varying noise characteristics, P300 duration and latency, and the parameters of Vector filter were also investigated. 相似文献
56.
Joachim Böttcher M.D. Alexander Pfeil Anders Rosholm Ph.D. Max-Ludwig Schäfer Ansgar Malich M.D. Alexander Petrovitch M.D. Bettina Seidl Gabriele Lehmann M.D. Hans-Joachim Mentzel M.D. Gert Hein M.D. Gunter Wolf M.D. Werner A. Kaiser M.D. M.S. 《Journal of digital imaging》2006,19(3):279-288
Purpose Our study evaluates digital x-ray radiogrammetry (DXR) and Radiogrammetry Kit (RK) as a new diagnostic method for the measurement
of disease-related osteoporosis including quantification of joint space narrowing dependent on the severity of rheumatoid
arthritis (RA).
Materials and Methods A total of 172 unselected patients with RA underwent computerized measurements of bone mineral density (BMD) and metacarpal
index (MCI) by DXR, as well as a semiautomated measurement of joint space distances at the metacarpal–phalangeal articulation
(JSD-MCP 2–5), both were analyzed from plain radiographs of the nondominant hand.
Results Correlations between DXR-BMD and DXR-MCI vs. parameters of RK were all significant (0.34 < R < 0.61; p < 0.01). An expected negative association was observed between RK parameters and the different scoring methods (−0.27 < R < −0.59). The maximum relative decrease in BMD vs. MCI as measured by DXR between the highest and lowest RA severity group
was −27.7% vs. −27.5% (p < 0.01) for the modified Larsen Score, whereas the minimal value of relative DXR-BMD and DXR-MCI reduction could be documented
for the Sharp Erosion Score (−20.8% vs. −26.8%; p < 0.01). The relative reduction of mean JSD-MCP using RK significantly varied from −25.0% (Sharp Erosion Score) to −41.2%
(modified Larsen Score). In addition, an excellent reproducibility of DXR and RK could be verified.
Conclusion DXR in combination with RK could be a promising, widely available diagnostic tool to supplement the different scoring methods
of RA with quantitative data, allowing an earlier and improved diagnosis and more precision in determining disease progression. 相似文献
57.
Strategic control and medial frontal negativity: beyond errors and response conflict 总被引:6,自引:0,他引:6
Errors in timed choice tasks typically produce an error-related negativity (ERN) in the event-related potential (ERP). The error specificity of the ERN has been challenged by studies showing a correct response negativity (CRN). Forty-five participants engaged in a flanker task in which both compatibility between flankers and target and the probability of compatible flankers were manipulated. Correct responses elicited a CRN, the amplitude of which increased with the degree of mismatch between the presence of conflict and conflict probability, even on low-conflict (compatible) trials. The fronto-central N2 component was larger on high-conflict (incompatible) correct response trials. However, in contrast to some recent accounts, this N2 was largest for highly probable stimuli. These findings suggest revision to models of the effects of conflict on response-related negativity to account for strategic adjustments made in preparation for the response. 相似文献
58.
Masi G Perugi G Toni C Millepiedi S Mucci M Bertini N Akiskal HS 《Journal of affective disorders》2004,78(3):175-183
BACKGROUND: Growing evidence documents the frequent co-morbidity between Obsessive Compulsive Disorder (OCD) and Bipolar Disorder (BP) in adults. The aim of the present study is to explore some clinical aspects of this interface in children and adolescents, as it appears in a setting of routine clinical practice. METHOD: The sample comprised 102 consecutively referred children and adolescents, both inpatients and outpatients, with BP, OCD or co-morbid BP-OCD during a 3-year period. The mean age was 14.2 (SD=3.2); 65 (63.7%) were males. Diagnoses and clinical features were collected by means of structured interview according to DSM-IV (DICA-R) and a rating scale for OCD (CY-BOCS). Clinical outcome was evaluated prospectively by means of clinical global impression (CGI) as part of routine clinical care, throughout the follow-up. RESULTS: Thirty-seven (36.3%) patients (21 males and 16 females) were diagnosed as BP, 35 (34.3%) patients (26 males and 9 females) were diagnosed as OCD and 30 (29.4%) patients (18 males and 12 females) were diagnosed as BP-OCD. BP II, was more frequent in the BP-OCD than in BP. When OCD was co-morbid with BP, age of onset was significantly earlier than in the 'pure' OCD patients. On the contrary, age of onset of BP was not affected by co-morbid OCD. According to CGI baseline scores, OCD patients were significantly less impaired than BP-OCD and BP patients, while the severity of the symptomatology was similar in the last two groups. Severity scores at the end of the follow-up were significantly higher in BP-OCD patients than in OCD patients. Patients with pure BP showed lower rates of panic disorder-agoraphobia than BP-OCD patients and higher rates of ADHD-conduct disorder. Pure OCD patients showed lower rates of ADHD and higher rates of Generalized Anxiety Disorder. The number of obsessions did not differentiate the two groups, whereas pure OCD patients showed significantly more compulsions. 'Other' obsessions-e.g., existential, philosophical, odd and/or superstitious-were significantly more frequent in BP-OCD than in pure OCD patients. Ordering compulsions were significantly more frequent in pure OCD patients. LIMITATIONS: Possible low reliability of children's and their parents' recall of past episodes of mental disorder. CONCLUSIONS: In a tertiary care center, co-morbidity between OCD and BP is a significant clinical problem affecting a large number of patients. The correct identification of OCD-bipolar co-morbidity has relevant clinical implications as far as other concomitant disorders, symptomatological features, course, complications, and treatment management and outcome are concerned. 相似文献
59.
60.