| 1. |
- Haghighi, Mona, et al.
(författare)
-
A Comparison of Rule-based Analysis with Regression Methods in Understanding the Risk Factors for Study Withdrawal in a Pediatric Study
- 2016
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- Regression models are extensively used in many epidemiological studies to understand the linkage between specific outcomes of interest and their risk factors. However, regression models in general examine the average effects of the risk factors and ignore subgroups with different risk profiles. As a result, interventions are often geared towards the average member of the population, without consideration of the special health needs of different subgroups within the population. This paper demonstrates the value of using rule-based analysis methods that can identify subgroups with heterogeneous risk profiles in a population without imposing assumptions on the subgroups or method. The rules define the risk pattern of subsets of individuals by not only considering the interactions between the risk factors but also their ranges. We compared the rule-based analysis results with the results from a logistic regression model in The Environmental Determinants of Diabetes in the Young (TEDDY) study. Both methods detected a similar suite of risk factors, but the rule-based analysis was superior at detecting multiple interactions between the risk factors that characterize the subgroups. A further investigation of the particular characteristics of each subgroup may detect the special health needs of the subgroup and lead to tailored interventions.
|
|
| 2. |
- Dicksved, Johan, et al.
(författare)
-
Lactobacillus reuteri Maintains a Functional Mucosal Barrier during DSS Treatment Despite Mucus Layer Dysfunction
- 2012
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 7:9
-
Tidskriftsartikel (refereegranskat)abstract
- Treatment with the probiotic bacterium Lactobacillus reuteri has been shown to prevent dextran sodium sulfate (DSS)-induced colitis in rats. This is partly due to reduced P-selectin-dependent leukocyte-and platelet-endothelial cell interactions, however, the mechanism behind this protective effect is still unknown. In the present study a combination of culture dependent and molecular based T-RFLP profiling was used to investigate the influence of L. reuteri on the colonic mucosal barrier of DSS treated rats. It was first demonstrated that the two colonic mucus layers of control animals had different bacterial community composition and that fewer bacteria resided in the firmly adherent layer. During DSS induced colitis, the number of bacteria in the inner firmly adherent mucus layer increased and bacterial composition of the two layers no longer differed. In addition, induction of colitis dramatically altered the microbial composition in both firmly and loosely adherent mucus layers. Despite protecting against colitis, treatment with L. reuteri did not improve the integrity of the mucus layer or prevent distortion of the mucus microbiota caused by DSS. However, L. reuteri decreased the bacterial translocation from the intestine to mesenteric lymph nodes during DSS treatment, which might be an important part of the mechanisms by which L. reuteri ameliorates DSS induced colitis.
|
|
| 3. |
- Schreiber, Olof, 1980-, et al.
(författare)
-
Influence of Lactobacillus reuteri on the colonic microbiota in health and DSS-induced colitis
-
Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Aim: To investigate the impact of Lactobacillus reuteri and Dextran Sulphate Sodium (DSS) on the colonic microbiota by investigating bacterial content and composition in the individual colonic mucus layers and mesenteric lymph nodes. Methods: Rats were divided into 4 groups: control, L. reuteri, DSS and L. reuteri+DSS. L. reuteri was given as a cocktail containing 109 cfu of four different strains of L. reuteri by gavage daily for 16 days. Colitis was induced by 5% DSS in the drinking water for 9 days. The firmly and loosely mucus layers and mesenteric lymph nodes were collected, homogenized and its bacterial content was monitored using both culturing as well as the molecular method terminal restriction fragment length polymorphism (TRFLP). Results: In controls, the number of bacteria was significantly lower in the inner firmly adherent mucus layer than the outer loosely adherent layer, indicating a barrier function of the inner mucus layer. The composition of the microbiota was also different between layers. L. reuteri prevented colitis but did not alter the microbiota. DSS obliterated the differences between mucus layers both in terms of number of bacteria, and bacterial composition, indicating that DSS destroys the mucus regardless of the addition of L. reuteri. L. reuteri did however significantly decrease bacterial translocation in the DSS-model. Conclusion: The firmly adherent mucus layer serves as a barrier towards luminal bacteria. DSS alters the colonic microbiota and destroys the mucus barrier. L. reuteri ameliorates DSS-colitis by decreasing bacterial translocation.
|
|
