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Selective inhibition of neuronal and inducible nitric oxide synthase (NOS) with 2-iminobiotin previously showed a reduction in brain cell injury. In the present study, we investigated the effects of 2-iminobiotin treatment on insulin-like growth factor-1 (IGF-1) expression, caspase activity and cytokine expression in a newborn piglet model of perinatal hypoxia-ischaemia. Newborn piglets were subjected to 1 h of hypoxia-ischaemia and were treated intravenously with vehicle or 2-iminobiotin. Vehicle-treated piglets showed reduced IGF-1 mRNA expression and increased caspase-3 activity and DNA fragmentation. 2-Iminobiotin treatment, administered immediately upon reperfusion, prevented these observations. No differences in caspase-8 and -9 activity and cytokine [interleukin (IL)-1alpha/beta, IL-6, tumour necrosis factor (TNF)-alpha, transforming growth factor (TGF)-beta] mRNA expression were demonstrated between vehicle- and 2-iminobiotin-treated piglets at 24 h following hypoxia-ischaemia. IGF-1 mRNA correlated inversely with caspase-3 and transferase-mediated dUTP-biotin in situ nick end labelling score in the cortex, but positively with caspase-8. Cytokine mRNA did not correlate with IGF-1 mRNA, caspase-3 activity or DNA fragmentation. The present results indicate that the previously demonstrated neuroprotective effect of 2-iminobiotin treatment after perinatal hypoxia-ischaemia coincided with a preservation of the endogenous IGF-1 production and reduced caspase-3 activity, but not with a significant decrease in cytokine production.  相似文献   
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BACKGROUND: Whereas several authors recently reported a positive association between the alpha2-macroglobulin gene (A2M) and late-onset AD (LOAD), others were unable to replicate these findings. Early-onset AD (EOAD) is defined as onset age <65 years. Virtually all patients with LOAD are >65 years of age. OBJECTIVE: To evaluate the role of A2M in AD, the authors conducted a population-based study of EOAD and LOAD as well as a meta-analysis of all studies conducted to date. METHODS: Patients with EOAD (n = 100) were derived from a population-based study in four northern provinces of the Netherlands and the area of metropolitan Rotterdam. Patients with LOAD (n = 344) were drawn from the Rotterdam Study, a population-based prospective study on residents aged 55 years and over of a Rotterdam suburb in the Netherlands. Two polymorphisms were studied, A2M-I/D and A2M-Ile1000Val, in relation to the APOE epsilon4 allele (APOE*4). RESULTS: No genotypic or allelic association was found for either polymorphism in the population-based series of patients with LOAD. In patients with EOAD without APOE*4, a significant increase of carriers of A2M-1000Val was found. The meta-analysis of available published case-control data on these polymorphisms in white and mixed ethnic populations yielded no significant differences between cases and controls. Pooling the Asian studies conducted to date showed a significant decrease in the frequency of A2M-D among patients. CONCLUSIONS: These results suggest that A2M is not genetically associated with LOAD in white patients or mixed populations as found in the United States. In these populations A2M does not have clinical relevance. From a scientific perspective, the findings on EOAD and Asian patients require replication and further research in the A2M region.  相似文献   
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OBJECTIVE: Coating of ventricular assist devices (VADs) with heparin improves the biocompatibility and may reduce the need for systemic anticoagulation. However, heparins are associated with the risk of formation of heparin/platelet factor 4 antibodies (HPF4/A) and the development of heparin-associated thromboemboli. We analyzed the occurrence of HPF4/A and thromboembolism in patients with heparin-coated and noncoated VADs. METHODS: One hundred patients were enrolled in the investigation. Fifty-seven received a heparin-coated (group 1) and 43 a noncoated (group 2) VAD. HPF4/A testing was performed before and 2 and 12 weeks after implantation by the heparin platelet factor 4 enzyme-linked immunosorbent assay. RESULTS: There was no significant difference in the occurrence of HPF4/A in the 2 groups (P =.102). Before the operation, 21 of the patients in group 1 had positive test responses and 25 in group 2. No patient had HPF4/A after termination of systemic heparinization. In group 1 there was no significant difference in the incidence of recurrent pump thromboses in patients who had positive test responses for HPF4/A (n = 11) when compared with those who had negative test responses (n = 9, P =.89). Twenty-one patients had HPF/A but no thromboembolism. However, all 22 patients who had thromboembolism had HPF4/A. CONCLUSIONS: Heparin coating of the VAD surface does not enhance the occurrence of HPF4/A-associated immunologic or thrombogenic reactions. However, the presence of these antibodies is strongly associated with an increased risk of thromboembolism in patients with a VAD.  相似文献   
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Overheating may cause terminal apnoea and cot death. Rectal temperature and breathing patterns were examined in normal infants at home during the first 6 months of life. Twenty one infants had continuous overnight rectal temperature and breathing recordings for 429 nights (mean 20.4 nights, range 7-30) spaced over the first six months of life. Periods when breathing was 'regular' were directly marked on single night records. Sleep state was determined from respiratory variables. 'Regular' breathing was a reliable marker of 'quiet' sleep (specificity 93%). The duration of 'quiet' sleep increased from 6 to 22 minutes from two weeks to three months of age and then remained static, as did the proportion of sleep spent in the quiet phase (9% to 34%). Rectal temperature fell during 66% of quiet sleep and usually rose during rapid eye movement (REM) sleep. The drop in rectal temperature was maximal at the start of quiet sleep, whereas the maximum rise during REM sleep was reached after 10 to 15 minutes. Oscillations in rectal temperature are associated with changes in sleep and breathing state. The maturation of rectal temperature patterns during the first six months of life are closely related to a maturation of sleep state and breathing patterns.  相似文献   
57.
Nasal dermoids are rare and their diagnosis is often delayed until complications occur. Signs such as a midline nasal punctum may be noted at birth but the significance of this finding frequently passes unrecognised. The cases are reported of two patients which illustrate the typical presentation of these lesions and their subsequent management is discussed.  相似文献   
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