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961.
BACKGROUND: Studies in humans and animals have suggested intrauterine programming of hypothalamic-pituitary-adrenal axis (HPAA) function as an important mechanism in linking fetal life conditions with adult disease. OBJECTIVE: Our aim was to assess how body size at birth, a marker of intrauterine conditions, is associated with hypothalamic-pituitary-adrenal axis response to psychosocial stress in late adulthood. DESIGN AND SETTING: We conducted a clinical study in the Helsinki Birth Cohort. PARTICIPANTS: Two hundred eighty-seven men and women born between 1934 and 1944 whose birth measurements and gestational age came from hospital records participated in the study. MEASUREMENTS: We measured salivary cortisol and, for 215 individuals, plasma cortisol and ACTH concentrations in conjunction with a standardized psychosocial stressor (Trier Social Stress Test). RESULTS: There was a linear relationship between low birth weight and low plasma ACTH but no linear relationship with cortisol. There were, however, quadratic relationships between birth weight and salivary (mixed model P = 0.001) and plasma cortisol (P = 0.005) but not with plasma ACTH (P = 0.1). The lowest peak salivary cortisol concentrations were seen in the lowest third of birth weights (adjusted for gestational age and sex): 12.9 nmol/liter (95% confidence interval of mean 11.2-15.0), compared with 17.1 nmol/liter (14.8-19.8) in the middle and 14.1 nmol/liter (12.6-15.7) in the highest third of birth weights. Corresponding figures for plasma cortisol were 418 nmol/liter (380-459), 498 nmol/liter (455-545), and 454 nmol/liter (428-482), and for plasma ACTH 8.17 pmol/liter (6.98-9.57), 12.42 pmol/liter (10.64-14.51), and 11.50 (10.06-13.14), respectively. Results for areas under the curve were similar. CONCLUSIONS: We found an inverse U-shaped relationship between birth weight and cortisol concentrations during psychosocial stress. The lowest cortisol and ACTH concentrations were seen in subjects with the lowest birth weights. These results support the hypothesis that both hyper- and hypocortisolism may be programmed during the fetal period.  相似文献   
962.
OBJECTIVE: The SLC11A1 (formerly called NRAMP1) gene is important in natural resistance to a variety of intracellular infections mediated by macrophages and has been proposed as a candidate gene for autoimmune disease susceptibility. The aim of this study was to examine susceptibility in Finnish patients with persistent oligoarticular and polyarticular rheumatoid factor (RF)-negative juvenile idiopathic arthritis (JIA) due to the presence of the SLC11A1 locus on chromosome 2. METHODS: A total of 234 Finnish JIA nuclear families and 639 elderly Finnish controls without a history of JIA were evaluated for association with JIA at 3 intragenic single-nucleotide polymorphisms: an intragenic insertion/deletion, a promoter microsatellite (NRAMP1), and a 3' microsatellite (D2S1471). RESULTS: Analysis of marker haplotypes demonstrated a strong association of Finnish JIA with 6-marker, 4-marker, and 2-marker haplotypes. Most impressively, 1 of the 6-marker haplotypes showed an odds ratio (OR) of 4.0 (95% confidence interval [95% CI] 2.6-6.2) in all JIA patients, 3.5 (95% CI 1.9-6.5) in those with persistent oligoarticular JIA, and 4.1 (95% CI 2.5-6.7) in those with polyarticular RF-negative JIA. Stratification of the haplotype data suggested that susceptibility to JIA in the haplotype spanning the SLC11A1 locus is independent (P < 0.01) of an association with a DRB1 JIA shared epitope (DRB1*JIASE) that includes well-characterized strong susceptibility to DRB1*08 and *11 alleles. This SLC11A1 haplotype also had an additive effect with DRB1*JIASE in those with polyarticular, but not those with persistent oligoarticular, disease (P = 0.06, OR 2.9 [95% CI 0.9-9.2] versus P = 0.5, OR 1.6 [95% CI 0.4-6.0]). CONCLUSION: Taken together, these data provide support for the existence of a locus at or near SLC11A1 that is a strong susceptibility factor for JIA in Finnish patients.  相似文献   
963.
To better understand the molecular events involved in the origin of new pathogenic bacteria, we studied the evolution of a highly virulent clone of serotype M1 group A Streptococcus (GAS). Genomic, DNA-DNA microarray, and single-nucleotide polymorphism analyses indicated that this clone evolved through a series of horizontal gene transfer events that involved (1) the acquisition of prophages encoding streptococcal pyrogenic exotoxin A and extracellular DNases and (2) the reciprocal recombination of a 36-kb chromosomal region encoding the extracellular toxins NAD+-glycohydrolase (NADase) and streptolysin O (SLO). These gene transfer events were associated with significantly increased production of SLO and NADase. Virtual identity in the 36-kb region present in contemporary serotype M1 and M12 isolates suggests that a serotype M12 strain served as the donor of this region. Multiple horizontal gene transfer events were a crucial factor in the evolutionary origin and emergence of a very abundant contemporary clone of serotype M1 GAS.  相似文献   
964.
Cord blood (CB) is used increasingly as a source of hematopoietic stem cells because of a lower risk of acute and chronic graft-versus-host disease (GVHD). However, there is some concern regarding the ability to adequately reconstitute host immune response due to the immaturity and naivety of CB T cells. This study was designed to evaluate T-cell reconstitution using combined approaches of phenotyping, analysis of alphabeta T-cell receptor (TCR) diversity, and assessment of ex vivo thymic function by measuring TCR rearrangement excision circles (TRECs). Ten patients who underwent CB transplantation for high-risk hematologic disorders were compared to a reference group of 19 age- and GVHD-matched patients who underwent transplantation with non-T cell-depleted bone marrow from an HLA-identical sibling donor. TREC values correlated with the relative number of naive T cells and with TCR repertoire polyclonality. During the first year after transplantation, TCR repertoires were highly abnormal and TREC values low in both groups. Notably, 2 years after transplantation onward TREC values as well as TCR diversity were higher in CB recipients than in recipients of bone marrow transplants. These data indicate an efficient thymic regeneration pathway from CB lymphoid progenitors despite the low number of cells infused compared to bone marrow, arguing for a complete clinical immune recovery after CB transplantation.  相似文献   
965.
Objective. We sought to determine the antiinflammatory properties of lymecycline in the long-term treatment of reactive arthritis (ReA). Methods. Quantitative assay of collagenase activity by densitometry after sodium dodecyl sulfatepolyacrylamide gel electrophoresis. Results. Therapeutic levels of lymecycline do not directly inhibit the activity of human neutrophil interstitial collagenase, but can prevent the oxidative activation of latent human neutrophil collagenase. Conclusion. This non-antimicrobial, anticollagenolytic property of lymecycline may contribute to its therapeutic efficacy in the treatment of patients with ReA.  相似文献   
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