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111.
Newborns and young infants suffer increased infectious morbidity and mortality as compared to older children and adults. Morbidity and mortality due to infection are highest during the first weeks of life, decreasing over several years. Furthermore, most vaccines are not administered around birth, but over the first few years of life. A more complete understanding of the ontogeny of the immune system over the first years of life is thus urgently needed. Here, we applied the most comprehensive analysis focused on the innate immune response following TLR stimulation over the first 2 years of life in the largest such longitudinal cohort studied to-date (35 subjects). We found that innate TLR responses (i) known to support Th17 adaptive immune responses (IL-23, IL-6) peaked around birth and declined over the following 2 years only to increase again by adulthood; (ii) potentially supporting antiviral defense (IFN-α) reached adult level function by 1 year of age; (iii) known to support Th1 type immunity (IL-12p70, IFN-γ) slowly rose from a low at birth but remained far below adult responses even at 2 years of age; (iv) inducing IL-10 production steadily declined from a high around birth to adult levels by 1 or 2 years of age, and; (v) leading to production of TNF-α or IL-1β varied by stimuli. Our data contradict the notion of a linear progression from an 'immature' neonatal to a 'mature' adult pattern, but instead indicate the existence of qualitative and quantitative age-specific changes in innate immune reactivity in response to TLR stimulation.  相似文献   
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Adoptive children are at increased risk for problematic behaviors but the origin of these individual differences in neurobehavioral function is unclear. This investigation examined whether adopted children with prenatal exposure to a wide variety of recreational drugs exhibited higher scores (i.e. more problems) with executive function and psychiatric symptomology. Caregivers of children ages 5 to 18 completed an online survey with items about use of alcohol, nicotine, or methamphetamine during pregnancy followed by the Behavior Rating Inventory of Executive Function (BRIEF, N = 437 including 59 adoptive parents) or the Child Behavior Checklist (CBCL, N = 549 including 54 adoptive parents). Relative to a comparison group of children raised by their biological parents, adoptive children that were polysubstance exposed during prenatal development exhibited higher rates of academic difficulties and were behind their classmates in math and reading. Adoptive children had statistically and clinically significant higher BRIEF ratings and this pattern was similar for boys and girls. CBCL ratings were significantly increased in adoptive children, particularly for Externalizing and Attention problems. Adoptive children with a history of polysubstance exposures including alcohol, nicotine, and methamphetamine are at heightened risk for difficulties with executive function as well as various psychopathologies. These findings suggest that increased monitoring to identify and implement remediation strategies may be warranted for adopted children with a history of in utero drug exposures.  相似文献   
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We used a random coefficient regression (RCR) model to estimate growth parameters for the time series of observed serum glucose levels in the Replicate 1 of the Genetic Analysis Workshop 13 simulated data. For comparison, a two time-point interval was also selected and the slope between these two observations was calculated. This process yielded four phenotypes: the RCR growth phenotype, a two time-point slope phenotype, and Time 1 and Time 2 serum glucose level phenotypes. These four phenotypes were used for linkage analyses on simulated chromosomes 5, 7, 9, and 21, those chromosomes that contained loci affecting the growth course for serum glucose levels. The linkage analysis of the RCR-derived phenotype showed overwhelming evidence for linkage at one locus (LOD 65.78 on chromosome 5), while showing elevated but nonsignificant LOD scores for two other loci (LOD 1.25 on chromosome 7, LOD 1.10 on chromosome 9), and no evidence of linkage for the final locus. The two time-point slope phenotype showed evidence for linkage at one locus (LOD 4.16 on chromosome 5) but no evidence for linkage at any of the other loci. A parallel cross-sectional approach, using as input phenotypes the endpoints of the two-point slope phenotype, gave strong linkage results for the major locus on chromosome 5 (maximal LOD scores of 17.90 and 27.24 for Time 1 and Time 2, respectively) while showing elevated but nonsignificant linkage results on chromosome 7 (maximal LOD scores of 1.71 and 1.48) and no evidence for linkage at the two remaining loci. The RCR growth parameter showed more power to detect linkage to the major locus than either the cross-sectional or two-point slope approach, but the cross-sectional approach gave a higher maximal LOD score for one of the minor loci.  相似文献   
115.
A novel epinephrine oxidation system in homogenates of the gorgonian Pseudoplexaura porosa was discovered. The enzymatic reaction required an unsaturated fatty acid and molecular oxygen or hydrogen peroxide. Diphenylisobenzofuran was also oxidized by Ps. porosa homogenates in the presence of an unsaturated fatty acid. Hydroxyl radical and superoxide anion did not appear to be involved in either of these oxidative reactions. The production of lipid hydroperoxides was not necessary for epinephrine oxidation and, with the exception of arachidonic acid, lipid hydroperoxide production did not occur. Evidence is presented for the involvement of singlet oxygen or a similar activated oxygen intermediate in the reactions, and a possible mechanism was proposed. The use of arachidonate-dependent epinephrine oxidation as a measure of prostaglandin synthetase activity is criticized.  相似文献   
116.
Abstract

A class of very potent nucleoside transport inhibitors is present in two molecular forms around physiological pH. We investigated whether the monoprotonated or the unionized species of these molecules binds to this camer protein with higher affinity.  相似文献   
117.
Extensive data on 102 patients who presented with rheumatoid disease within a year of onset were gathered by a prospective study to assess the prognostic value of early features. Outcome was evaluated at a mean 4-5 years from onset on the basis of functional grade, extent of joint disease, early morning stiffness, and grip strength. Twenty-six patients improved, 14 pursued a mild steady course, and 62 had a persistently severe or deteriorating condition. The features recorded at the first visit were correlated with outcome. Those indicating a poor prognosis were: older age at onset, being underweight, poor grip strength, many affected joints, involvement of wrist or metatarsophalangeal joints, poor functional status, fulfilment of many of the American Rheumatism Association criteria for rheumatoid disease, raised erythrocyte sedimentation rate, seropositivity on sheep cell agglutination or latex tests, low haemoglobin level, raised blood urea level, and early erosions on x-ray films.  相似文献   
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Classical protein import, mediated by the binding of a classical nuclear localization signal (NLS) to the NLS receptor, karyopherin/importin alpha, is the most well studied nuclear transport process. Classical NLSs are either monopartite sequences that contain a single cluster of basic amino acids (Lys/Arg) or bipartite sequences that contain two clusters of basic residues separated by an unconserved linker region. We have created mutations in conserved residues in each of the three NLS-binding sites/regions in Saccharomyces cerevisiae karyopherin alpha (SRP1). For each mutant we have analyzed binding to both a monopartite and a bipartite NLS cargo in vitro. We have also expressed each karyopherin alpha mutant in vivo as the only cellular copy of the NLS receptor and examined the impact on cell growth and import of both monopartite and bipartite NLS-containing cargoes. Our results reveal the functional significance of specific residues within karyopherin alpha for NLS cargo binding. A karyopherin alpha variant with a mutation in the major NLS-binding site exhibits decreased binding to both monopartite and bipartite NLS cargoes, and this protein is not functional in vivo. However, we also find that a karyopherin alpha variant with a mutation in the minor NLS-binding site, which shows decreased binding only to bipartite NLS-containing cargoes, is also not functional in vivo. This suggests that the cell is dependent on the function of at least one bipartite NLS cargo that is imported into the nucleus by karyopherin alpha. Our experiments also reveal functional importance for the linker-binding region. This study provides insight into how changes in binding to cellular NLS sequences could impact cellular function. In addition, this work has led to the creation of conditional alleles of karyopherin alpha with well characterized defects in NLS binding that will be useful for identifying and characterizing novel NLS cargoes.  相似文献   
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