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61.
Silviu-Alin Bacanu Cynthia M Bulik Kelly L Klump Manfred M Fichter Katherine A Halmi Pamela Keel Allan S Kaplan James E Mitchell Alessandro Rotondo Michael Strober Janet Treasure D Blake Woodside Vibhor A Sonpar Weiting Xie Andrew W Bergen Wade H Berrettini Walter H Kaye Bernie Devlin 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2005,(1):61-68
To increase the likelihood of finding genetic variation conferring liability to eating disorders, we measured over 100 attributes thought to be related to liability to eating disorders on affected individuals from multiplex families and two cohorts: one recruited through a proband with anorexia nervosa (AN; AN cohort); the other recruited through a proband with bulimia nervosa (BN; BN cohort). By a multilayer decision process based on expert evaluation and statistical analysis, six traits were selected for linkage analysis (1): obsessionality (OBS), age at menarche (MENAR), and anxiety (ANX) for quantitative trait locus (QTL) linkage analysis; and lifetime minimum body mass index (BMI), concern over mistakes (CM), and food-related obsessions (OBF) for covariate-based linkage analysis. The BN cohort produced the largest linkage signals: for QTL linkage analysis, four suggestive signals: (for MENAR, at 10p13; for ANX, at 1q31.1, 4q35.2, and 8q13.1); for covariate-based linkage analyses, both significant and suggestive linkages (for BMI, one significant [4q21.1] and three suggestive [3p23, 10p13, 5p15.3]; for CM, two significant [16p13.3, 14q21.1] and three suggestive [4p15.33, 8q11.23, 10p11.21]; and for OBF, one significant [14q21.1] and five suggestive [4p16.1, 10p13.1, 8q11.23, 16p13.3, 18p11.31]). Results from the AN cohort were far less compelling: for QTL linkage analysis, two suggestive signals (for OBS at 6q21 and for ANX at 9p21.3); for covariate-based linkage analysis, five suggestive signals (for BMI at 4q13.1, for CM at 11p11.2 and 17q25.1, and for OBF at 17q25.1 and 15q26.2). Overlap between the two cohorts was minimal for substantial linkage signals. 相似文献
62.
Sequence of the structural gene (rmpM) for the class 4 outer membrane protein of Neisseria meningitidis, homology of the protein to gonococcal protein III and Escherichia coli OmpA, and construction of meningococcal strains that lack class 4 protein 总被引:2,自引:7,他引:2
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The structural gene (rmpM) of the class 4 outer membrane protein of Neisseria meningitidis has been cloned and sequenced. The derived amino acid sequence reveals a 218-amino-acid protein following a 22-amino-acid signal peptide. The protein shows 94.2% homology with protein III of Neisseria gonorrhoeae and shares its two potential disulfide loops. The protein also shares limited homology with Escherichia coli OmpA. N. gonorrhoeae protein III has been shown to elicit blocking antibodies that prevent the killing of serum-resistant strains by immune sera (P. A. Rice, H. E. Vayo, M. R. Tam, and M. S. Blake, J. Exp. Med. 164:1735-1748, 1986). The very close homology of meningococcal class 4 protein with gonococcal protein III suggests that meningococcal outer membrane preparations containing class 4 protein may similarly stimulate blocking antibodies. In order to investigate the role of the class 4 protein in the pathogenesis of meningococcal infection, we have used an erythromycin resistance gene in developing two meningococcal strains that lack class 4 protein. 相似文献
63.
Summary
Gaeumannomyces graminis var.graminis andtritici were transformed to benomyl resistance using pBT3, a plasmid encoding fungicide-resistant -tubulin. Either circular or linear plasmid DNA producedG. graminis var.graminis transformants in which plasmid DNA was integrated into the fungal genome. There was no evidence for autonomous plasmid replication in any of the transformants examined. 4/11 linear DNA transformants had a single plasmid copy, whereas 8/9 circular DNA transformants had multiple copies of the plasmid. Integration of transforming DNA occurred by nonhomologous recombination in all (20/20) of these transformants. 相似文献
64.
Gonococcal lipooligosaccharide sialylation prevents complement-dependent killing by immune sera. 总被引:6,自引:5,他引:6
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Previous investigators have demonstrated that a sialic acid residue is added to the terminal galactose moiety of gonococcal lipooligosaccharide (LOS) when incubated with 5'-CMP-N-acetylneuraminic acid. When this in vitro sialylation occurs, gonococci become resistant to the bactericidal activity of normal human serum. This is believed to result because the added sialic acid residue blocks the binding of bactericidal anti-LOS antibodies present in normal human serum. We extend these studies by demonstrating that sialylated gonococci also become resistant to the bactericidal effect of immune sera containing antibodies that recognize exposed components of the outer membrane besides LOS. Prevention of antibody binding to the organism was not the cause, since the same percentage of bactericidal antibodies to the major outer membrane protein, Protein I, can be absorbed with sialylated organisms as with wild-type organisms. In addition, gonococcal sialylation prevents opsonophagocytosis by antigonococcal antisera. The negative effect of sialic acid on the complement pathway might be the reason for the findings in this study. 相似文献
65.
66.
Qualter Pamela Rouncefield-Swales Alison Bray Lucy Blake Lucy Allen Steven Probert Chris Crook Kay Carter Bernie 《Quality of life research》2021,30(2):497-506
Quality of Life Research - Adolescents and young adults (AYA) with Inflammatory Bowel Disease (IBD) report higher depressive symptoms and anxiety compared to healthy controls, with disease severity... 相似文献
67.
Yang M Jiang X Blake D Zhang Z Macey M Newland A Morris C 《International journal of oncology》1993,3(1):99-104
We have compared the specific activities of Cu/Zn superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) in a vinblastine sensitive human T-lymphoblastic cell line (CCRF-CEM) and its multiple drug resistant (MDR) counterpart cell line (CEM/VLB100), which over-expresses P-glycoprotein (PGP). We have found that the specific activity Cu/Zn SOD was consistently 38% increased in CEM/VLB100 cells compared with CCRF-CEM cells. In contrast, the activities of CAT and GSH-Px were similar in the two cell lines. These results suggest that MDR in CEM/VLB100 is a complicated phenotype which not only involves a PGP mechanism, but also a SOD protection mechanism against drug-mediated O2.- cytotoxicity. 相似文献
68.
The individual educational and intervention emphasis of clinical preventive medicine programs is successful in reducing an employee's risk for disease and injury. Although some studies note that decreased risk is found predominantly in those with low initial risk, a critical mass of healthful lifestyles may spread to non-participants in the organization, the halo effect. Thus, the more employees there are modeling a health lifestyle, the greater likelihood others will follow. Preventive medicine programs offer intangible advantages to the employer. Such programs demonstrate an attitude of caring for the employee which has an influence on the public. Happier employees tend to increase their level of socialization within a company. The ultimate effect is decreased employee risk, improved productivity, reduced absenteeism, and improved health at reduced cost. 相似文献
69.
An Unexpected Change in DXA Calibration not Detected by Routine Quality Control Checks 总被引:2,自引:0,他引:2
G. M. Blake N. G. Preston R. Patel R. J. M. Herd I. Fogelman 《Osteoporosis international》1999,9(2):115-120
Since its commercial introduction a decade ago, the technique of dual-energy X-ray absorptiometry (DXA) has been widely recognized
as a useful and sensitive method of measuring changes in bone mineral density (BMD) at selected sites in the skeleton such
as the spine and proximal femur. Because of their high precision and stable calibration, DXA scanners are frequently used
in clinical trials to evaluate new treatments for osteoporosis. Quality assurance procedures based on regular scanning of
phantoms are widely adopted in such trials, and continuity of the phantom BMD measurements is generally believed to ensure
continuity in the in-vivo calibration. We report a change in calibration of a DXA scanner that occurred during a clinical
trial where the calibration shift was different for the spine and femur sites and was not predicted or explained by the standard
quality control procedures using phantoms. However, we show that provided patients enrolled in studies are thoroughly randomized
and the statistical analysis is confined to the differences between the treated and control groups, then the effects of such
calibration shifts on conclusions regarding the efficacy of treatment are considerably smaller than the random statistical
errors.
Received: 12 February 1998 / Accepted: 20 May 1998 相似文献
70.
Whang W Sisk JE Heitjan DF Moskowitz AJ 《International journal of technology assessment in health care》1999,15(3):563-572
OBJECTIVES: We explore the policy implications of probabilistic sensitivity analysis in cost-effectiveness analysis by applying simulation methods to a decision model. METHODS: We present the multiway sensitivity analysis results of a study of the cost-effectiveness of vaccination against pneumococcal bacteremia in the elderly. We then execute a probabilistic sensitivity analysis of the cost-effectiveness ratio by specifying posterior distributions for the uncertain parameters in our decision analysis model. In order to estimate probability intervals, we rank the numerical values of the simulated incremental cost-effectiveness ratios (ICERs) to take into account preferences along the cost-effectiveness plane. RESULTS: The 95% probability intervals for the ICER were generally much narrower than the difference between the best case and worst case results from a multiway sensitivity analysis. Although the multiway sensitivity analysis had indicated that, in the worst case, vaccination in the 85 and older age group was not acceptable from a policy standpoint, probabilistic methods indicated that the cost-effectiveness of vaccination was below $50,000 per quality-adjusted life-year in greater than 92% of the simulations and below $100,000 in greater than 95% of the simulations. CONCLUSIONS: Probabilistic methods can supplement multiway sensitivity analyses to provide a more comprehensive picture of the uncertainty associated with cost-effectiveness ratios and thereby inform policy decisions. 相似文献