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81.
OBJECTIVE: Recent studies have demonstrated an association between a 192 bp polymorphism of the IGF-I gene and total IGF-I serum levels, birth weight, body height and the risk of developing diabetes and cardiovascular diseases later on in life. This IGF-I gene polymorphism in the promoter region of the IGF-I gene may directly influence the expression of IGF-I. In the present study we evaluated the role of this polymorphism in the age-related decline in serum IGF-I levels. SUBJECTS AND METHODS: All subjects were participants of the Rotterdam Study, a population-based cohort study of diseases in the elderly. We studied a total group of 346 subjects, who comprised two subgroups: a randomly selected population-based sample of 196 subjects, and a group of 150 subjects selected on IGF-I genotype. In the total group of 346 individuals the relationship between this 192 bp polymorphism and the age-related decline in circulating total IGF-I levels was studied. RESULTS: Homozygous carriers of the 192 bp allele demonstrated significant decline in serum IGF-I with age (r=-0.29, P=0.002). This decline is similar to that seen in the general population. An age-related decline in serum total IGF-I was not observed in heterozygotes (r=-0.06, P=0.48) and non-carriers (r = -0.12, P=0.32). Interestingly, the relationship between age and serum IGF-binding protein-3 levels showed the same pattern. CONCLUSION: We observed only in homozygous carriers of the 192 bp alleles of the IGF-I gene an age-related decline in circulating total IGF-I levels, but not in heterozygotes and non-carriers of the 192 bp allele. We hypothesize that this IGF-I gene polymorphism directly or indirectly influences GH-mediated regulation of IGF-I secretion.  相似文献   
82.
Objective. To investigate the extent to which early radiologic damage is predicted by joint inflammation in patients with newly diagnosed rheumatoid arthritis (RA). Methods. Regression analysis was performed on 1-year progression of total radiologic damage for baseline characteristics and cumulative disease activity measures, and the effects of continued joint inflammation on the progression of damage in separate joint groups were investigated. Results. Odds ratios for progression of total damage were 12 for the presence of rheumatoid factor, 5 for the presence of damage at baseline, and 2 for cumulative joint inflammation. A positive association between continued joint inflammation and progression of damage was found to be statistically significant for most joint groups. Conclusion. Progression of radiologic damage in patients with newly diagnosed RA is independently associated with the presence of rheumatoid factor and damage at baseline and with cumulative joint inflammation.  相似文献   
83.
Frozen brain specimens from six patients with subacute sclerosing panencephalitis (SSPE) were analyzed immunohistochemically for the presence of leukocyte subpopulations and specific cytokines. In brain regions demonstrating perivascular cell infiltration and gliosis, CD4 and CD8 positive cells were identified within the brain parenchyma. Cytokine analysis revealed cells staining positively for tumor necrosis factor-alpha and interferon-gamma. These results were similar to those observed in multiple sclerosis (MS) and progressive rubella panencephalitis tissue and were different from other predominantly noninflammatory neurologic diseases and normal controls. Although SSPE and MS differ significantly in their etiology and histopathology, the similarities in leukocyte and cytokine staining patterns suggest a common mechanism of disease progression.  相似文献   
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Neurogenic mediastinal tumors in adults are generally benign lesions and for this reason are ideal candidates for resection by video-assisted thoracoscopy (VAT). Usual contraindications to VAT are the dimension of the tumor (greater than 6 cm), its position (apex, posterior costodiaphragmatic angle), and/or the presence of intraspinal growth (the so-called "dumbbell tumors"). This study reviewed a single-institution 10-year experience approaching mediastinal neurogenic tumors routinely by VAT, even in cases of the above mentioned contraindications. From January 1992 to December 2002, 15 consecutive mediastinal neurogenic tumors were operated by VAT (11 females, mean age 43 years, range 16-67). Mean operating time was 99 minutes (range 60-180). No conversion thoracotomy was required. The 2 cases of "dumbbell tumor" in this series were treated by laminectomy followed by VAT. Two patients had a Claude-Bernard-Horner syndrome after removal of lesion at the level of T1-T2. Mean postoperative stay was 5.5 days. Histologic diagnosis was schwannoma in 12 cases (Antoni type A in 7 cases, type B in 4 cases, mixed type in 1 case) and neurofibroma in 3 cases. Results from this 10-year experience confirmed that VAT can be the standard approach for neurogenic tumors in adults without negative effect on radicality of resection and safety of the procedure.  相似文献   
86.
Temperament and psychopathology are intimately related; however, research on the prospective associations between positive emotionality, defined as a child’s positive mood states and high engagement with the environment, and psychopathology is inconclusive. We examined the longitudinal relation between positive emotionality and internalizing problems in young children from the general population. Furthermore, we explored whether executive functioning mediates any observed association. Within a population-based Dutch birth cohort, we observed positive emotionality in 802 children using the laboratory temperament assessment battery at age 3 years. Child behavior checklist (CBCL) internalizing problems (consisting of Emotionally Reactive, Anxious/Depressed, and Withdrawn scales) were assessed at age 6 years. Parents rated their children’s executive functioning at ages 4 years. Children with a lower positive emotionality at age 3 had a higher risk of withdrawn problems at age 6 years (OR = 1.20 per SD decrease in positive emotionality score, 95 % CI: 1.01, 1.42). This effect was not explained by preexisting internalizing problems. This association was partly mediated by more problems in the shifting domain of executive functioning (p < 0.001). We did not find any relation between positive emotionality and the CBCL emotionally reactive or anxious/depressed scales. Although the effect sizes were moderate, our results suggest that low levels of positive emotionality at preschool age can result in children’s inflexibility and rigidity later in life. The inflexibility and rigidity are likely to affect the child’s drive to engage with the environment, and thereby lead to withdrawn problems. Further research is needed to replicate these findings.  相似文献   
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88.
Nuclear receptor subfamily 4, group A, member 2 (NR4A2, also called Nurr1) has lately become of interest with regard to atherogenesis. We examined the association between common variation in the NR4A2 gene and cardiovascular disease in the Rotterdam Study, a prospective population‐based study among persons aged ≥55 years. Three SNPs that tag common haplotypes across a 36‐kb region surrounding the NR4A2 gene were determined. Four haplotypes with frequencies >1% covered 96% of the genetic variation. In 5,650 participants without history of coronary heart disease, 729 coronary heart disease events occurred during a median follow‐up time of 11.9 years. NR4A2 haplotypes were neither associated with coronary events nor with intima‐media thickness (IMT), carotid plaques, or ankle‐arm index (AAI). NR4A2 haplotypes showed a tendency toward associations with aortic and coronary calcification (haplo.score global simulation P values 0.076 and 0.075, respectively), which seemed to be based on haplotype 2 (individual P values were both P=0.015). Furthermore, NR4A2 haplotype 3 was associated with higher high‐density lipoprotein (HDL) cholesterol and haplotype 4 with lower systolic blood pressure. In conclusion, NR4A2/NURR1 haplotypes were not associated with coronary events, carotid IMT, carotid plaques, or AAI. There was a tendency toward associations with aortic calcification and coronary calcification. Associations for NR4A2 were found with both HDL levels and blood pressure. It remains to be investigated which pathophysiological mechanisms pertain to NR4A2 function in cardiovascular disease. Hum Mutat 0, 1–7, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
89.
Background Symptoms of allergy are largely attributed to an IgE‐mediated hypersensitivity response. However, a considerable number of patients also exhibit clinical features of allergy without detectable systemic IgE. Previous work showed that Ig‐free light chains (IgLC) may act as an alternate mechanism to induce allergic responses. CD4+CD25+ T cells are crucial in the initiation and regulation of allergic responses and compromised function might affect the response to allergens. Objective To examine the contribution of CD4+CD25+ T cells and IgLC towards the whey‐allergic response. Methods Mice were sensitized orally with whey using cholera toxin as an adjuvant. CD25+ T cells were depleted in vivo using a CD25 mAb. The acute allergic skin response to whey and ex vivo colon reactivity was measured in the presence or absence of F991, a specific inhibitor of IgLC. Serum whey‐specific antibodies and IgLC in serum and mesenteric lymph node (MLN) supernatants were measured. Depletion of CD4+CD25+ T cells was confirmed in the spleen. Results Anti‐CD25 treatment strongly reduced whey‐specific antibody levels and resulted in a partial depletion of effector T cells and a major depletion of Foxp3+ regulatory T cells. Surprisingly, despite the abolished specific IgE response, the acute allergic skin response to whey was not affected. IgLC levels were enhanced in the serum and MLN supernatants of CD25‐depleted sensitized mice. F991 inhibited the acute skin response and colon hyperreactivity in anti‐CD25‐treated mice, indicating that these responses were mainly IgLC dependent. Conclusions Depletion of CD4+CD25+ T cells resulted in a switch from an IgE‐ to an IgLC‐dependent acute skin response and functional hyperresponsiveness of the colon. Our data suggest that CD25+ T cells play a crucial role in balancing cow's milk allergy between IgE and IgE‐independent responses and both mechanisms might play a role in allergic responses to the same allergen. Cite this as: B. C. A. M. van Esch, B. Schouten, B. R. J. Blokhuis, G. A. Hofman, L. Boon, J. Garssen L. M. J. Knippels, L. E. M. Willemsen and F. A. Redegeld, Clinical & Experimental Allergy, 2010 (40) 1414–1421.  相似文献   
90.
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