Risk Calculations (risk + calculation)

Distribution by Scientific Domains


Selected Abstracts


Quantitative analysis of association between herpesviruses and bacterial pathogens in periodontitis

JOURNAL OF PERIODONTAL RESEARCH, Issue 3 2008
I. Saygun
Background and Objective:, The development of human periodontitis may depend upon cooperative interactions among herpesviruses, specific pathogenic bacteria and tissue-destructive inflammatory mediators. This study sought to identify associations among human cytomegalovirus, Epstein,Barr virus and six putative periodontopathic bacteria in periodontitis lesions. Material and Methods:, Fifteen periodontitis patients (nine with aggressive periodontitis and six with chronic periodontitis) and 15 periodontally normal subjects were included in the study. In each study subject, a microbiological sample was collected, using a curette, from the deepest periodontal probing depth of the dentition. A real-time TaqMan® polymerase chain reaction assay was employed to determine the subgingival counts of human cytomegalovirus, Epstein,Barr virus, Porphyromonas gingivalis, Tannerella forsythia, Prevotella intermedia, Aggregatibacter actinomycetemcomitans, Fusobacterium nucleatum and Campylobacter rectus. Statistical analysis was performed using the Student's t -test, the Pearson correlation coefficient test and the single variable logistic regression test for odds ratio-based risk calculation. Results:, Human cytomegalovirus was detected in eight periodontitis lesions and in one normal periodontal site, Epstein,Barr virus was detected in nine periodontitis lesions and in two normal periodontal sites, and the study bacteria were detected in 6,15 periodontitis lesions and in 1,11 normal periodontal sites. Correlations were found between counts of human cytomegalovirus and Epstein,Barr virus, between counts of human cytomegalovirus and P. gingivalis, T. forsythia and C. rectus, and between counts of Epstein,Barr virus and P. gingivalis and T. forsythia. Human cytomegalovirus and Epstein,Barr virus counts were also positively associated with the level of periodontal attachment loss, probing pocket depth and gingival bleeding on probing. Conclusion:, This study confirmed that periodontal human cytomegalovirus and Epstein,Barr virus are associated with major periodontopathic bacteria and with the severity of periodontal disease. The finding of abundant herpesviruses in periodontitis lesions redefines the pathogenic paradigm of the disease. Understanding the interplay between herpesviruses and specific bacterial species in the pathogenesis of periodontitis may form the basis for new approaches to preventing, reducing or delaying tissue breakdown from periodontal infections. [source]


Influence of maternal systemic lupus erythematosus on first-trimester combined screening for chromosomal abnormalities

PRENATAL DIAGNOSIS, Issue 7 2007
J. Heinig
Abstract Objective To explore the effect of maternal systemic lupus erythematosus (SLE) on first-trimester screening markers for Down syndrome. Methods A retrospective study was conducted on 1150 normal singleton fetuses that underwent first-trimester combined screening for Down syndrome. Fetal delta nuchal translucency (NT), maternal serum PAPP-A and free ,-hCG were compared between pregnancies with SLE (n = 10) and without preexisting maternal disease (n = 1140). Results The medians ± SD for delta NT, log10 MoM of PAPP-A and free ,-hCG ± SD in pregnancies with SLE and without maternal disease were , 0.18 ± 0.29 versus , 0.18 ± 0.33, 0.005 ± 0.32 versus 0.02 ± 0.26, and 0.22 ± 0.19 versus , 0.014 ± 0.28, with a p value of 0.7, 0.98 and 0.03, respectively. Conclusions Patients with preexisting SLE have increased maternal serum-free ,-hCG levels in the first-trimester. But, because of the multimodal procedure of risk calculation there is no significant difference in the screen-positive rate after the combined first-trimester screening for trisomy 21. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Does safety science fulfill the requirements of modern technical systems?

HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 3 2003
Albert Kuhlmann
Since the idea of safety science was first conceived, technical systems have grown larger and increasingly complex, thus causing a pronounced impact on the complexity of required safety analyses and risk calculations. The author emphasizes his point of view that the physical risk definition provides the most appropriate concept for engineers when it comes to planning including risk cadastres. In order to avoid human errors, he pleads for the consideration of human factors in the early design phase and for interdisciplinary cooperation. © 2003 Wiley Periodicals, Inc. Hum Factors Man 13: 223,230, 2003. [source]


Population screening for fetal trisomy 21: easy access to screening should be balanced against a uniform ultrasound protocol

PRENATAL DIAGNOSIS, Issue 11 2005
Wilfried J. A. Gyselaers
Abstract Objectives To evaluate the performance of a first-trimester fetal aneuploidy screening program, with a documented underestimation of nuchal translucency thickness measurements (NT) compared to the Fetal Medicine Foundation (FMF) reference range. Methods We analysed the data of Algemeen Medisch Laboratorium (AML) in Antwerp, Belgium, on combined screening with pregnancy-associated plasma protein-A (PAPP-A), free ,-human chorionic gonadotropin (FB-hCG) and NT. NT-multiples of the median (MoM), relative to the FMF reference range, were used for risk calculations. Results The proportion of first-trimester screening tests in the total of serum screening tests increased from 1.3% (125/9424) in 2000 to 53.1% (6577/12 377) in 2003. Only 11.4% (1514/13 267) of NT measurements were performed according to FMF criteria. The 80.8% (21/26) trisomy 21 (T21) detection rate (DR) at cut off 1:300 resulted from maternal serum screening. NT measurements did not add to this DR, but reduced the false-positive rate from 16.8% (2212/13181) to 8.6% (1130/13181). Only 23.8% (5/21) of T21 detections were by FMF trainees. Conclusion Easy access to screening and maternal serum parameters accounted for the majority of T21 detections in our first-trimester combined screening program. Copyright © 2005 John Wiley & Sons, Ltd. [source]


A common genetic background for inflammatory bowel disease and ankylosing spondylitis: A genealogic study in Iceland

ARTHRITIS & RHEUMATISM, Issue 8 2007
Bjarni Thjodleifsson
Objective Patients with ankylosing spondylitis (AS) and ,50% of their first-degree relatives may have a genetic abnormality that results in subclinical intestinal inflammation. This study was undertaken to examine the familial occurrence and cosegregation of AS and inflammatory bowel disease (IBD) in order to determine whether there is a shared genetic risk factor in families. Methods The Icelandic genealogy database and population-wide data on all living Icelanders diagnosed as having AS (n = 205) and/or IBD (n = 1,352) were used to estimate the risk ratios of AS for relatives of patients with AS, the risk ratios of IBD for relatives of patients with IBD, and the cross-risk ratios of AS for relatives of patients with IBD or of IBD for relatives of patients with AS. The mean kinship coefficients for each disease were calculated. The control population for disease risk calculations comprised 10,000,100,000 sets of matched Icelandic subjects. Results First-, second-, and third-degree relatives of patients with AS had risk ratios of 94, 25, and 3.5, respectively, indicating an increased risk of developing AS (each P < 0.0005), while first-, second-, and third-degree relatives of patients with IBD had risk ratios for IBD of 4.4, 2.2, and 1.4, respectively (each P < 0.0001). The cross-risk ratios of IBD were 3.0 and 2.1 in first- and second-degree relatives of patients with AS, respectively, and were the same for AS in first- and second-degree relatives of patients with IBD. With the exception of Crohn's disease, the risk of having AS, ulcerative colitis, or IBD in spouses of patients with these diseases did not differ significantly from that in controls. Calculation of the kinship coefficients confirmed these patterns of familial risk. Conclusion Patients with AS or IBD in Iceland are significantly more related to each other than are randomly sampled control subjects, in terms of an increased risk of either or both conditions developing in third-degree relatives. These findings suggest that one or more undiscovered genetic variants may underlie the risk of both diseases. [source]