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21.
Comorbidity is pervasive among both adult and child psychiatric disorders; however, the etiological mechanisms underlying the majority of comorbidities are unknown. This study used genetic linkage analysis to assess the etiology of comorbidity between reading disability (RD) and attention‐deficit hyperactivity disorder (ADHD), two common childhood disorders that frequently co‐occur. Sibling pairs (N = 85) were ascertained initially because at least one individual in each pair exhibited a history of reading difficulties. Univariate linkage analyses in sibling pairs selected for ADHD from within this RD‐ascertained sample suggested that a quantitative trait locus (QTL) on chromosome 6p is a susceptibility locus for ADHD. Because this QTL is in the same region as a well‐replicated QTL for reading disability, subsequent bivariate analyses were conducted to test if this QTL contributed to comorbidity between the two disorders. Analyses of data from sib pairs selected for reading deficits revealed suggestive bivariate linkage for ADHD and three measures of reading difficulty, indicating that comorbidity between RD and ADHD may be due at least in part to pleiotropic effects of a QTL on chromosome 6p. © 2002 Wiley‐Liss, Inc.  相似文献   
22.
Under current practices of mouse colony maintenance, sera from mice are analyzed for antibodies against several widespread infectious pathogens by conventional immunoassays, generally enzyme-linked immunosorbent assay (ELISA). To test for multiple agents, these methods consume large volumes of mouse serum and are laborious and time-consuming. More efficient immunoassays, using small amounts of sample, are therefore needed. Accordingly, we have developed a novel multiplex diagnostic system that employs fluorescent microbeads, coated with purified antigens, for simultaneous serodetection of 10 mouse infectious agents. Individually identifiable, fluorescent microbeads were coated with antigens from Sendai virus, mouse hepatitis virus, Theiler's mouse encephalomyelitis virus/GDVII strain, mouse minute virus, mouse cytomegalovirus, respiratory enteric orphan virus (Reo-3 virus), mouse parvovirus, calf rotavirus for epizootic diarrhea virus of infant mice, vaccinia virus for ectromelia virus, and Mycoplasma pulmonis. Standard sera, singly positive for antibodies to individual infectious agents, were generated by inoculation of BALB/cj and C57BL/6j mice. Sera from these experimentally infected mice, as well as sera from naturally infected mice, were analyzed using a mixture of microbeads coated with antigens of the 10 infectious agents listed above. Results demonstrated that the multiplex assay was at least as sensitive and specific as ELISA for serodetection. Importantly, the multiplex assay required only 1 microliter of serum for simultaneous serodetection of the 10 mouse infectious agents in one reaction vessel. Thus, this multiplex microbead assay is a reliable, efficient, and cost-effective diagnostic modality that will impact serosurveillance of mice used in research.  相似文献   
23.
The inflammatory bowel diseases (IBDs), Crohn's disease (CD) and ulcerative colitis, are chronic inflammatory disorders of the digestive tract. The pathogenesis of IBD is complicated, and it is widely accepted that immunologic, environmental and genetic components contribute to its etiology. To identify genetic susceptibility factors in CD, we performed a genome-wide association study in Japanese patients and controls using nearly 80,000 gene-based single nucleotide polymorphism (SNP) markers and investigated the haplotype structure of the candidate locus in Japanese and European patients. We identified highly significant associations (P = 1.71 x 10(-14) with odds ratio of 2.17) of SNPs and haplotypes within the TNFSF15 (the gene encoding tumor necrosis factor superfamily, member 15) genes in Japanese CD patients. The association was confirmed in the study of two European IBD cohorts. Interestingly, a core TNFSF15 haplotype showing association with increased risk to the disease was common in the two ethnic groups. Our results suggest that the genetic variations in the TNFSF15 gene contribute to the susceptibility to IBD in the Japanese and European populations.  相似文献   
24.
The design and feasibility of genetic studies of complex diseases are critically dependent on the extent and distribution of linkage disequilibrium (LD) across the genome and between different populations. We have examined genomewide and region-specific LD in a young genetically isolated population identified in the Netherlands by genotyping approximately 800 Short Tandem Repeat markers distributed genomewide across 58 individuals. Several regions were analyzed further using a denser marker map. The permutation-corrected measure of LD was used for analysis. A significant (P<0.0004) relation between LD and genetic distance on a genomewide scale was found. Distance explained 4% of the total LD variation. For fine-mapping data, distance accounted for a larger proportion of LD variation (up to 39%). A notable similarity in the genomewide distribution of LD was revealed between this population and other young genetically isolated populations from Micronesia and Costa Rica. Our study population and experiment was simulated in silico to confirm our knowledge of the history of the population. High agreement was observed between results of analysis of simulated and empirical data. We conclude that our population shows a high level of LD similar to that demonstrated previously in other young genetic isolates. In Europe, there may be a large number of young genetically isolated populations that are similar in history to ours. In these populations, a similar degree of LD is expected and thus they may be effectively used for linkage or LD mapping.  相似文献   
25.

Objective

The aim of this study is to investigate the impact of treatment policy changes in cervical cancer patients treated with adjuvant (chemo) radiotherapy.

Methods

Between 1970 and 2007, 292 patients received adjuvant radiotherapy after a radical hysterectomy with pelvic lymphadenectomy for early stage cervical carcinoma. All patients received pelvic radiotherapy (40 Gy–46 Gy in 1.8 Gy–2 Gy/fraction). Vaginal vault brachytherapy boost (10–14 Gy) was increasingly used for patients with high-risk factors, and since 1993 systematically applied in patients with at least 2 of the 3 risk factors: adenocarcinoma, nodal involvement and parametrial invasion. Cisplatin-based chemotherapy was introduced in this group of patients from 2000.

Results

The 5-year cumulative risk of local recurrence (CRLR) was 13% (95%CI 9%–17%), resulting in an overall 5-year survival (OS) of 78% (95%CI 83%–73%). Since 1970, the OR for the 5-year locoregional recurrence risk (LRR) decreased from 2.5 to 1.15 (linear-OR = − 0.02/year). The OR for the 5-year mortality risk reduced from 2.2 in 1970 to 1.0 in 2007 (linear-OR = − 0.03/year). The largest risk reductions were observed before 1990 with a minor rise after 2002. The risk of severe late toxicity reduced from 1.8% to 1.5% (linear-OR = − 0.03/year). The addition of concomitant adjuvant chemotherapy since 2000 may have benefited a subgroup of patients with squamous cell carcinoma, but not the patients with adenocarcinoma, and after introduction of chemotherapy the risk of severe late toxicity tripled from 2% to 7%.

Conclusion

Since 1970, tumour recurrence risk and mortality have decreased, as radiation dose increased. The potential benefit of concomitant adjuvant chemotherapy could not be demonstrated in this nonrandomized study.  相似文献   
26.
Pathogen recognition and binding are crucial functions of innate immunity. It has been observed that the short pentraxin superfamily including C-reactive protein (CRP) and serum amyloid P component are pathogen pattern recognition receptors (PRR) in the plasma. We isolated and characterized a novel and distinctive pentraxin from the plasma of horseshoe crab, Carcinoscorpius rotundicauda, henceforth named CrOctin, which binds to bacteria via phosphoethanolamine (PE), a chemical component present on lipid A and core polysaccharide moieties of bacterial lipopolysaccharide (LPS). Infection enhances the formation of the PRR interactome constituting CrOctin, CRP and galactose-binding protein. In particular, infection increases the affinity of CRP to CrOctin by 1000-fold. Furthermore, we observed that by binding to PE, CrOctin acts as a linker that bridges the PRR interactome to the inner core of LPS. On the other hand, under normal physiological conditions, binding of CrOctin to PE appears to obscure other PRR from interacting directly with PE. Interestingly, the cluster of "CrOctin-interactive PRR" is sex specific. We report, for the first time, the change in PRR protein profiles with a distinctive gender difference during Pseudomonas infection.  相似文献   
27.
The transforming growth factor-beta1 (TGF-beta1) is involved in post-ischemic neuronal rescue and in beta-amyloid turn-over. We hypothesized that the risk for dementia and related neuropathologies is modified by the TGF-beta1 functional genetic variants. The association of the TGF-beta1+29T-->C polymorphism with dementia was examined in a sample of 261 cases and 491 controls from the Honolulu-Asia Aging Study, including 282 subjects with autopsy data. Dementia was assessed in 1991 and 1994 by a multi-step protocol and standardized diagnostic criteria. The analysis was adjusted for demographic and vascular factors. Compared to the TT genotype, the TC and the CC genotypes were associated with a reduced risk for vascular dementia (OR(TC)=0.28, 95% confidence interval (CI): 0.1-0.9; OR(CC)=0.28, CI: 0.1-0.9), microinfarcts (OR(CC)=0.31, CI: 0.13-0.71) and cerebral amyloid angiopathy (OR(CC)=0.48, CI: 0.2-0.9). The CC genotype was associated with an increase risk of neocortical plaques (OR(CC)=4.34, CI: 1.6-11.8). These preliminary data suggest that the TGF genetic variability may be important in the risk of vascular related dementia.  相似文献   
28.
OBJECTIVE: To identify genomic regions linked with determinants of age at symptom onset, disease activity, and functional impairment in ankylosing spondylitis (AS). METHODS: A whole genome linkage scan was performed in 188 affected sibling pair families with 454 affected individuals. Traits assessed were age at symptom onset, disease activity assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), and functional impairment assessed by the Bath Ankylosing Spondylitis Functional Index (BASFI). Parametric and nonparametric quantitative linkage analysis was performed using parameters defined in a previous segregation study. RESULTS: Heritabilities of the traits studied in this data set were as follows: BASDAI 0.49 (P = 0.0001, 95% confidence interval [95% CI] 0.23-0.75), BASFI 0.76 (P = 10(-7), 95% CI 0.49-1.0), and age at symptom onset 0.33 (P = 0.005, 95% CI 0.04-0.62). No linkage was observed between the major histocompatibility complex (MHC) and any of the traits studied (logarithm of odds [LOD] score <1.0). "Significant" linkage (LOD score 4.0) was observed between a region on chromosome 18p and the BASDAI. Age at symptom onset showed "suggestive" linkage to chromosome 11p (LOD score 3.3). Maximum linkage with the BASFI was seen at chromosome 2q (LOD score 2.9). CONCLUSION: In contrast to the genetic determinants of susceptibility to AS, clinical manifestations of the disease measured by the BASDAI, BASFI, and age at symptom onset are largely determined by a small number of genes not encoded within the MHC.  相似文献   
29.
This four-year outcome study examines the results of the VA Contracted Residential Substance Abuse Treatment for veterans with substance abuse problems. Race, marital status, housing status, and exposure to combat in the military characterized the male veteran subjects. Hospitalization rates and arrest rates were tracked for two years prior to and two years post-residential treatment. The authors also examined treatment outcomes for those who completed outpatient substance abuse treatment after an episode of residential care. This study shows a 30% reduction of hospitalizations and arrests following residential treatment. Those veterans who completed both residential and outpatient treatment had the best outcomes in terms of number of hospitalizations and arrests in a two-year follow-up.  相似文献   
30.
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