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Using a two‐stage global scan design, we analyzed general population replicates 1 and 42 of the Genetic Analysis Workshop (GAW) 12 simulated data set using three methods: revisited Haseman‐Elston (HER), maximum likelihood variance estimation (ML), and variance components (VC). Three marker densities, 5‐, 10‐, and 15‐cM intervals, were examined in the first‐stage scan. We found that the 10‐cM interval appears to be the most cost‐effective approach in genotyping without sacrificing power when using a first stage significance level of 0.01. Subsequently, we performed the second‐stage scan at 1‐cM intervals for those putative positive regions identified in the first‐stage scan at a significance level of 0.01. We also compared the power to detect linkage using different numbers of sib pairs for a genome‐wide scan at a 10‐cM interval and found that power decreases nonlinearly as the number of sib pairs decreases. © 2001 Wiley‐Liss, Inc. 相似文献
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Jennie Ponsford Rochelle Whelan-Goodinson Alex Bahar-Fuchs 《Brain injury : [BI]》2007,21(13):1385-1392
Primary objectives: To establish pre-morbid alcohol and drug use in persons with TBI, relative to controls, investigate how patterns of substance use change over time following TBI and identify factors associated with heavy post-injury substance use.
Methods and procedures: The Alcohol Use Disorders Identification test (AUDIT) and Drug Abuse Screening Test (DAST) was completed by 121 hospital inpatients with TBI, documenting pre-injury alcohol and drug use, and 133 demographically similar controls. Participants with TBI completed these measures and the Hospital Anxiety and Depression Scale (HADS) again 1 and 2 years post-injury and 76 also completed them at 3 years.
Results: Participants with TBI showed similar levels of drug and alcohol use to controls pre-injury, with 31.4% of the TBI group and 29.3% of controls drinking at hazardous levels. Alcohol and drug use declined in the first year post-injury, but increased by 2 years post-injury, with only 21.4% of participants with TBI reporting abstinence from alcohol and 25.4% drinking at hazardous levels. Only 9% showed a drug problem, but 24% had returned to some drug use. Those showing heavy alcohol use post-injury were young, male and heavy drinkers pre-injury. Drug and alcohol use was similar at 3 years post-injury.
Conclusions: More active intervention is needed to reduce alcohol and drug use following TBI. 相似文献
Methods and procedures: The Alcohol Use Disorders Identification test (AUDIT) and Drug Abuse Screening Test (DAST) was completed by 121 hospital inpatients with TBI, documenting pre-injury alcohol and drug use, and 133 demographically similar controls. Participants with TBI completed these measures and the Hospital Anxiety and Depression Scale (HADS) again 1 and 2 years post-injury and 76 also completed them at 3 years.
Results: Participants with TBI showed similar levels of drug and alcohol use to controls pre-injury, with 31.4% of the TBI group and 29.3% of controls drinking at hazardous levels. Alcohol and drug use declined in the first year post-injury, but increased by 2 years post-injury, with only 21.4% of participants with TBI reporting abstinence from alcohol and 25.4% drinking at hazardous levels. Only 9% showed a drug problem, but 24% had returned to some drug use. Those showing heavy alcohol use post-injury were young, male and heavy drinkers pre-injury. Drug and alcohol use was similar at 3 years post-injury.
Conclusions: More active intervention is needed to reduce alcohol and drug use following TBI. 相似文献
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Simple Method for Detection of Penicillinase-Producing Neisseria gonorrhoeae 总被引:3,自引:0,他引:3 下载免费PDF全文
A simple, reliable, and economical method for detection of penicillinase-producing Neisseria gonorrhoeae using a penicillin disk and a penicillin-sensitive organism is described. 相似文献
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ApoAI deficiency results in marked reductions in plasma cholesterol but no alterations in amyloid-beta pathology in a mouse model of Alzheimer's disease-like cerebral amyloidosis 下载免费PDF全文
Fagan AM Christopher E Taylor JW Parsadanian M Spinner M Watson M Fryer JD Wahrle S Bales KR Paul SM Holtzman DM 《The American journal of pathology》2004,165(4):1413-1422
Epidemiological studies suggest links between cholesterol metabolism and Alzheimer's disease (AD), with hypercholesterolemia associated with increased AD risk, and use of cholesterol-lowering drugs associated with decreased risk. Animal models using cholesterol-modifying dietary or pharmacological interventions demonstrate similar findings. Proposed mechanisms include effects of cholesterol on the metabolism of amyloid-beta (Abeta), the protein that deposits in AD brain. To investigate the effect of genetic alterations in plasma cholesterol on Abeta pathology, we crossed the PDAPP transgenic mouse model of AD-like cerebral amyloidosis to apolipoprotein AI-null mice that have markedly reduced plasma cholesterol levels due to a virtual absence of high density lipoproteins, the primary lipoprotein in mice. Interestingly and in contrast to models using non-physiological high fat diets or cholesterol-lowering drugs to modify plasma cholesterol, we observed no differences in Abeta pathology in PDAPP mice of the various apoAI genotypes despite robust differences in plasma cholesterol levels between the groups. Absence of apoAI also resulted in reductions in brain but not cerebrospinal fluid cholesterol, but had no effect on brain apolipoprotein E levels. These and other data suggest that it is perhaps the level of brain apolipoprotein E, not cholesterol per se, that plays a primary role in brain Abeta metabolism. 相似文献
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Alyce C. Russell Agnieszka Kepka Irena Trbojević-Akmačić Ivo Ugrina Manshu Song Jennie Hui Michael Hunter Simon M. Laws Gordan Lauc Wei Wang 《Immunobiology》2019,224(1):110-115
Background
Increased body fat may be associated with an increased risk of developing an underlying pro-inflammatory state, thus leading to greater risk of developing certain chronic conditions. Immunoglobulin G has the ability to exert both anti- and pro-inflammatory effects, and the N-glycosylation of the fragment crystallisable portion is involved in mediating this process. Body mass index, a rudimentary yet gold standard indication for body fat, has been shown to be associated with agalactosylated immunoglobulin G N-glycans.Aim
We aimed to determine the association between increased body fat and the immunoglobulin G glycosylation features, comparing body mass index to other measures of body fat distribution.Methods
We investigated a sample of 637 community-based 45–69?year olds, with mixed phenotypes, residing in Busselton, Western Australia. Body mass index and the waist-to-hip and waist-to-height ratios were calculated using anthropometry, while dual-energy x-ray absorptiometry was performed to gain an accurate measure of total and area specific body fat. Serum immunoglobulin GN-glycans were analysed by ultra-performance liquid chromatography.Results
Twenty-two N-glycan peaks were found to be associated with at least one of the fat measures. While the previous association of body mass index to agalactosylated immunoglobulin G was replicated, measures of central adiposity explained the most variation in the immunoglobulin G glycome.Conclusion
Central adiposity is associated with an increased pro-inflammatory fraction of immunoglobulin G, suggesting that the android/gynoid ratio or waist-to-height ratio instead be considered when controlling for adiposity in immunoglobulin G glycome biomarker studies. 相似文献9.
Fine Mapping Functional Sites or Regions from Case-Control Data Using Haplotypes of Multiple Linked SNPs 总被引:1,自引:0,他引:1
Previously, we reported an algorithm for scanning a large number of tightly linked single nucleotide polymorphisms (SNPs) for LD mapping of functional sites or regions from a family‐based association design. In the present study, we extend our method to a case‐control design. We first use the expectation maximization (EM) algorithm to estimate haplotype frequencies of multiple linked SNPs, and follow this by constructing a contingency table statistic S for LD analysis, based on the estimated haplotype frequencies. An empirical p‐value is obtained based on the null distribution of the maximum of S (S *) from a large number (e.g., 1,000 or more) of randomized permutations. The proposed algorithm has been implemented in a computer program in which window searching for functional SNP sites can cover any number of loci without limitation, except that of computer storage. Unlike other programs for a case‐control design that always conduct tests at a fix window width, in our program after setting a maximum size of haplotype window width, for a given maximum window width all possible widths of haplotypes are utilized to find the maximum statistic S * for each locus under investigation. The sensitivity of the proposed algorithm has been examined with simulated and real genotyping datasets. Association analyses indicate that our program is powerful enough to detect most, if not all, functional SNPs simulated in the original model or identified in the original report. Moreover, the program is very flexible and can be used in either regional or genome‐wide scanning for association analysis with SNP markers. 相似文献
10.
Schultz MJ Knapp S Florquin S Pater J Takeda K Akira S van der Poll T 《Infection and immunity》2003,71(4):1630-1634
Interleukin-18 (IL-18) is a potent cytokine with many different proinflammatory activities. To study the role of IL-18 in the pathogenesis of Pseudomonas pneumonia, IL-18-deficient (IL-18(-/-)) and wild-type mice were intranasally inoculated with Pseudomonas aeruginosa. IL-18 deficiency was associated with reduced outgrowth of Pseudomonas in the lungs and diminished dissemination of the infection. In addition, pulmonary inflammation (histopathology) and levels of tumor necrosis factor alpha, IL-6, and macrophage inflammatory protein-2 in lungs and plasma were lower in IL-18(-/-) mice. Consistent with results obtained for IL-18(-/-) mice, treatment of wild-type mice with a neutralizing IL-18 binding protein-immunoglobulin G Fc fusion construct also attenuated outgrowth of Pseudomonas compared with that for mice treated with a control protein. These results demonstrate that the presence of endogenous IL-18 activity facilitates inflammatory responses in the lung during Pseudomonas pneumonia, concurrently impairing bacterial clearance. 相似文献