| 1. |
- Kurilshikov, Alexander, et al.
(författare)
-
Large-scale association analyses identify host factors influencing human gut microbiome composition
- 2021
-
Ingår i: Nature Genetics. - : Nature Publishing Group. - 1061-4036 .- 1546-1718. ; 53:2, s. 156-165
-
Tidskriftsartikel (refereegranskat)abstract
- To study the effect of host genetics on gut microbiome composition, the MiBioGen consortium curated and analyzed genome-wide genotypes and 16S fecal microbiome data from 18,340 individuals (24 cohorts). Microbial composition showed high variability across cohorts: only 9 of 410 genera were detected in more than 95% of samples. A genome-wide association study of host genetic variation regarding microbial taxa identified 31 loci affecting the microbiome at a genome-wide significant (P < 5 x 10(-8)) threshold. One locus, the lactase (LCT) gene locus, reached study-wide significance (genome-wide association study signal: P = 1.28 x 10(-20)), and it showed an age-dependent association with Bifidobacterium abundance. Other associations were suggestive (1.95 x 10(-10) < P < 5 x 10(-8)) but enriched for taxa showing high heritability and for genes expressed in the intestine and brain. A phenome-wide association study and Mendelian randomization identified enrichment of microbiome trait loci in the metabolic, nutrition and environment domains and suggested the microbiome might have causal effects in ulcerative colitis and rheumatoid arthritis.
|
|
| 2. |
- Middha, Pooja K., et al.
(författare)
-
A genome-wide gene-environment interaction study of breast cancer risk for women of European ancestry
- 2023
-
Ingår i: Breast Cancer Research. - : BioMed Central (BMC). - 1465-5411 .- 1465-542X. ; 25:1
-
Tidskriftsartikel (refereegranskat)abstract
- Background Genome-wide studies of gene-environment interactions (GxE) may identify variants associated with disease risk in conjunction with lifestyle/environmental exposures. We conducted a genome-wide GxE analysis of similar to 7.6 million common variants and seven lifestyle/environmental risk factors for breast cancer risk overall and for estrogen receptor positive (ER +) breast cancer. Methods Analyses were conducted using 72,285 breast cancer cases and 80,354 controls of European ancestry from the Breast Cancer Association Consortium. Gene-environment interactions were evaluated using standard unconditional logistic regression models and likelihood ratio tests for breast cancer risk overall and for ER + breast cancer. Bayesian False Discovery Probability was employed to assess the noteworthiness of each SNP-risk factor pairs. Results Assuming a 1 x 10(-5) prior probability of a true association for each SNP-risk factor pairs and a Bayesian False Discovery Probability < 15%, we identified two independent SNP-risk factor pairs: rs80018847(9p13)-LINGO2 and adult height in association with overall breast cancer risk (ORint = 0.94, 95% CI 0.92-0.96), and rs4770552(13q12)-SPATA13 and age at menarche for ER + breast cancer risk (ORint = 0.91, 95% CI 0.88-0.94). Conclusions Overall, the contribution of GxE interactions to the heritability of breast cancer is very small. At the population level, multiplicative GxE interactions do not make an important contribution to risk prediction in breast cancer.
|
|
| 3. |
- Bonfiglio, F., et al.
(författare)
-
Female-Specific Association Between Variants on Chromosome 9 and Self-Reported Diagnosis of Irritable Bowel Syndrome
- 2018
-
Ingår i: Gastroenterology. - : Elsevier BV. - 0016-5085 .- 1528-0012. ; 155:1, s. 168-179
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND & AIMS: Genetic factors are believed to affect risk for irritable bowel syndrome (IBS), but there have been no sufficiently powered and adequately sized studies. To identify DNA variants associated with IBS risk, we performed a genome-wide association study (GWAS) of the large UK Biobank population-based cohort, which includes genotype and health data from 500,000 participants. METHODS: We studied 7,287,191 high-quality single nucleotide polymorphisms in individuals who self-reported a doctor's diagnosis of IBS (cases; n = 9576) compared to the remainder of the cohort (controls; n = 336,499) (mean age of study subjects, 40-69 years). Genome-wide significant findings were further investigated in 2045 patients with IBS from tertiary centers and 7955 population controls from Europe and the United States, and a small general population sample from Sweden (n = 249). Functional annotation of GWAS results was carried out by integrating data from multiple biorepositories to obtain biological insights from the observed associations. RESULTS: We identified a genome-wide significant association on chromosome 9q31.2 (single nucleotide polymorphism rs10512344; P = 3.57 x 10(-8)) in a region previously linked to age at menarche, and 13 additional loci of suggestive significance (P < 5.0 x 10(-6)). Sex-stratified analyses revealed that the variants at 9q31.2 affect risk of IBS in women only (P = 4.29 x 10(-10) in UK Biobank) and also associate with constipation-predominant IBS in women (P = .015 in the tertiary cohort) and harder stools in women (P = .0012 in the population-based sample). Functional annotation of the 9q31.2 locus identified 8 candidate genes, including the elongator complex protein 1 gene (ELP1 or IKB-KAP), which is mutated in patients with familial dysautonomia. CONCLUSIONS: In a sufficiently powered GWAS of IBS, we associated variants at the locus 9q31.2 with risk of IBS in women. This observation may provide additional rationale for investigating the role of sex hormones and autonomic dysfunction in IBS.
|
|
| 4. |
- Jung, Christian, et al.
(författare)
-
A comparison of very old patients admitted to intensive care unit after acute versus elective surgery or intervention
- 2019
-
Ingår i: Journal of critical care. - : W B SAUNDERS CO-ELSEVIER INC. - 0883-9441 .- 1557-8615. ; 52, s. 141-148
-
Tidskriftsartikel (refereegranskat)abstract
- Background: We aimed to evaluate differences in outcome between patients admitted to intensive care unit (ICU) after elective versus acute surgery in a multinational cohort of very old patients (80 years; VIP). Predictors of mortality, with special emphasis on frailty, were assessed.Methods: In total, 5063 VIPs were induded in this analysis, 922 were admitted after elective surgery or intervention, 4141 acutely, with 402 after acute surgery. Differences were calculated using Mann-Whitney-U test and Wilcoxon test. Univariate and multivariable logistic regression were used to assess associations with mortality.Results: Compared patients admitted after acute surgery, patients admitted after elective surgery suffered less often from frailty as defined as CFS (28% vs 46%; p < 0.001), evidenced lower SOFA scores (4 +/- 5 vs 7 +/- 7; p < 0.001). Presence of frailty (CFS >4) was associated with significantly increased mortality both in elective surgery patients (7% vs 12%; p = 0.01), in acute surgery (7% vs 12%; p = 0.02).Conclusions: VIPs admitted to ICU after elective surgery evidenced favorable outcome over patients after acute surgery even after correction for relevant confounders. Frailty might be used to guide clinicians in risk stratification in both patients admitted after elective and acute surgery.
|
|
| 5. |
- Nichols, Hazel B., et al.
(författare)
-
The Premenopausal Breast Cancer Collaboration : A Pooling Project of Studies Participating in the National Cancer Institute Cohort Consortium
- 2017
-
Ingår i: Cancer Epidemiology, Biomarkers and Prevention. - : AMER ASSOC CANCER RESEARCH. - 1055-9965 .- 1538-7755. ; 26:9, s. 1360-1369
-
Forskningsöversikt (refereegranskat)abstract
- Breast cancer is a leading cancer diagnosis among premenopausal women around the world. Unlike rates in postmenopausal women, incidence rates of advanced breast cancer have increased in recent decades for premenopausal women. Progress in identifying contributors to breast cancer risk among premenopausal women has been constrained by the limited numbers of premenopausal breast cancer cases in individual studies and resulting low statistical power to subcategorize exposures or to study specific subtypes. The Premenopausal Breast Cancer Collaborative Group was established to facilitate cohort-based analyses of risk factors for premenopausal breast cancer by pooling individuallevel data from studies participating in the United States National Cancer Institute Cohort Consortium. This article describes the Group, including the rationale for its initial aims related to pregnancy, obesity, and physical activity. We also describe the 20 cohort studies with data submitted to the Group by June 2016. The infrastructure developed for this work can be leveraged to support additional investigations.
|
|
| 6. |
- Schoemaker, Minouk J, et al.
(författare)
-
Association of Body Mass Index and Age With Subsequent Breast Cancer Risk in Premenopausal Women.
- 2018
-
Ingår i: JAMA Oncology. - : American Medical Association (AMA). - 2374-2437 .- 2374-2445. ; 4:11
-
Tidskriftsartikel (refereegranskat)abstract
- Importance: The association between increasing body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) and risk of breast cancer is unique in cancer epidemiology in that a crossover effect exists, with risk reduction before and risk increase after menopause. The inverse association with premenopausal breast cancer risk is poorly characterized but might be important in the understanding of breast cancer causation.Objective: To investigate the association of BMI with premenopausal breast cancer risk, in particular by age at BMI, attained age, risk factors for breast cancer, and tumor characteristics.Design, Setting, and Participants: This multicenter analysis used pooled individual-level data from 758 592 premenopausal women from 19 prospective cohorts to estimate hazard ratios (HRs) of premenopausal breast cancer in association with BMI from ages 18 through 54 years using Cox proportional hazards regression analysis. Median follow-up was 9.3 years (interquartile range, 4.9-13.5 years) per participant, with 13 082 incident cases of breast cancer. Participants were recruited from January 1, 1963, through December 31, 2013, and data were analyzed from September 1, 2013, through December 31, 2017.Exposures: Body mass index at ages 18 to 24, 25 to 34, 35 to 44, and 45 to 54 years.Main Outcomes and Measures: Invasive or in situ premenopausal breast cancer.Results: Among the 758 592 premenopausal women (median age, 40.6 years; interquartile range, 35.2-45.5 years) included in the analysis, inverse linear associations of BMI with breast cancer risk were found that were stronger for BMI at ages 18 to 24 years (HR per 5 kg/m2 [5.0-U] difference, 0.77; 95% CI, 0.73-0.80) than for BMI at ages 45 to 54 years (HR per 5.0-U difference, 0.88; 95% CI, 0.86-0.91). The inverse associations were observed even among nonoverweight women. There was a 4.2-fold risk gradient between the highest and lowest BMI categories (BMI≥35.0 vs <17.0) at ages 18 to 24 years (HR, 0.24; 95% CI, 0.14-0.40). Hazard ratios did not appreciably vary by attained age or between strata of other breast cancer risk factors. Associations were stronger for estrogen receptor-positive and/or progesterone receptor-positive than for hormone receptor-negative breast cancer for BMI at every age group (eg, for BMI at age 18 to 24 years: HR per 5.0-U difference for estrogen receptor-positive and progesterone receptor-positive tumors, 0.76 [95% CI, 0.70-0.81] vs hormone receptor-negative tumors, 0.85 [95% CI: 0.76-0.95]); BMI at ages 25 to 54 years was not consistently associated with triple-negative or hormone receptor-negative breast cancer overall.Conclusions and Relevance: The results of this study suggest that increased adiposity is associated with a reduced risk of premenopausal breast cancer at a greater magnitude than previously shown and across the entire distribution of BMI. The strongest associations of risk were observed for BMI in early adulthood. Understanding the biological mechanisms underlying these associations could have important preventive potential.
|
|
| 7. |
- Zhang, Xuehong, et al.
(författare)
-
Carotenoid intakes and risk of breast cancer defined by estrogen receptor and progesterone receptor status : a pooled analysis of 18 prospective cohort studies
- 2012
-
Ingår i: American Journal of Clinical Nutrition. - : OXFORD UNIV PRESS. - 0002-9165 .- 1938-3207. ; 95:3, s. 713-725
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Epidemiologic studies examining associations between carotenoid intakes and risk of breast cancer by estrogen receptor (ER) and progesterone receptor (PR) status are limited. Objective: We investigated these associations in a pooled analysis of 18 cohort studies. Design: Of 1,028,438 participants followed for a maximum follow-up of 26 y across studies, 33,380 incident invasive breast cancers were identified. Study-specific RRs and 95% CIs were estimated by using Cox proportional hazards regression and then pooled by using a random-effects model. Results: alpha-Carotene, beta-carotene, and lutein/zeaxanthin intakes were inversely associated with the risk of ER-negative (ER-) breast cancer (pooled multivariable RRs of the comparison between the highest and lowest quintiles): alpha-carotene (0.87; 95% CI: 0.78, 0.97), beta-carotene (0.84; 95% CI: 0.77, 0.93), and lutein/zeaxanthin (0.87; 95% CI: 0.79, 0.95). These variables were not inversely associated with the risk of ER-positive (ER+) breast cancer (pooled multivariable RRs for the same comparison): a-carotene (1.04; 95% CI: 0.99, 1.09), beta-carotene (1.04; 95% CI: 0.98, 1.10), and lutein/zeaxanthin (1.00; 95% CI: 0.93, 1.07). Although the pooled RRs for quintile 5 for beta-cryptoxanthin were not significant, inverse trends were observed for ER- and ER+ breast cancer (P-trend <= 0.05). Nonsignificant associations were observed for lycopene intake. The associations were largely not appreciably modified by several breast cancer risk factors. Nonsignificant associations were observed for PR-positive and PR-negative breast cancer. Conclusions: Intakes of alpha-carotene, beta-carotene, and lutein/zeaxanthin were inversely associated with risk of ER-, but not ER+, breast cancer. However, the results need to be interpreted with caution because it is unclear whether the observed association is real or due to other constituents in the same food sources. Am J Clin Nutr 2012;95:713-25.
|
|
| 8. |
- Henstrom, M., et al.
(författare)
-
Functional variants in the sucrase-isomaltase gene associate with increased risk of irritable bowel syndrome
- 2018
-
Ingår i: Gut. - : BMJ. - 0017-5749 .- 1468-3288. ; 67:2, s. 263-270
-
Tidskriftsartikel (refereegranskat)abstract
- Objective IBS is a common gut disorder of uncertain pathogenesis. Among other factors, genetics and certain foods are proposed to contribute. Congenital sucraseisomaltase deficiency (CSID) is a rare genetic form of disaccharide malabsorption characterised by diarrhoea, abdominal pain and bloating, which are features common to IBS. We tested sucrase-isomaltase (SI) gene variants for their potential relevance in IBS. Design We sequenced SI exons in seven familial cases, and screened four CSID mutations (p.Val557Gly, p. Gly1073Asp, p.Arg1124Ter and p.Phe1745Cys) and a common SI coding polymorphism (p.Val15Phe) in a multicentre cohort of 1887 cases and controls. We studied the effect of the 15Val to 15Phe substitution on SI function in vitro. We analysed p.Val15Phe genotype in relation to IBS status, stool frequency and faecal microbiota composition in 250 individuals from the general population. Results CSID mutations were more common in patients than asymptomatic controls (p=0.074; OR=1.84) and Exome Aggregation Consortium reference sequenced individuals (p=0.020; OR=1.57). 15Phe was detected in 6/7 sequenced familial cases, and increased IBS risk in case-control and population-based cohorts, with best evidence for diarrhoea phenotypes (combined p=0.00012; OR=1.36). In the population-based sample, 15Phe allele dosage correlated with stool frequency (p=0.026) and Parabacteroides faecal microbiota abundance (p=0.0024). The SI protein with 15Phe exhibited 35% reduced enzymatic activity in vitro compared with 15Val (p<0.05). Conclusions SI gene variants coding for disaccharidases with defective or reduced enzymatic activity predispose to IBS. This may help the identification of individuals at risk, and contribute to personalising treatment options in a subset of patients.
|
|
| 9. |
- Larsson, M., et al.
(författare)
-
Brain Response to Expectation and Delivery of Rectal Distensions Before and After Hypnotherapy and Education Intervention in Irritable Bowel Syndrome (IBS) : an fMRI Study
- 2011
-
Konferensbidrag (refereegranskat)abstract
- Aim & MethodsWe aimed to determine the effect of standardized hypnosis treatment (HYP) on symptom outcomes and brain activity compared to an education intervention (EDU). Twenty-seven women with IBS were evaluated before and after treatment with hypnotherapy (n=17) or educational intervention (n=10). Behavioural treatment outcomes were determined by Severity Scoring System (IBS-SSS). A decrease of 50 points in SSS score was considered clinically significant treatment response. Blood oxygenated level dependent (BOLD) signal were acquired by using a 1.5 T magnetic resonance scanner during expectation and delivery of large rectal distension (45 mmHg). Group comparisons of treatment effects were performed within the general linear model in SPM8. Region of interest analyses were performed with significance threshold of p<0.05, family-wise error corrected.ResultsThere were no group differences in baseline SSS scores. Clinically significant change in SSS was observed in HYP (82%, n=14) and EDU (60%, n=6). Mean improvement in SSS was 108 (range -277 to 29) in HYP and 62 (range -250 to 79) in EDU (ns). During cued expectation of rectal distension, HYP was associated with significantly decreased activation in the left dorsal and ventral anterior insula, left mid insula, left ventrolateral prefrontal cortex (vlPFC) and left dorsolateral prefrontal cortex (dlPFC). Respectively, the EDU group showed less BOLD activity in the left ventral anterior insula after treatment. No significant treatment effect on brain response to the 45 mmHg distension was observed.ConclusionWhile both treatments improve IBS symptoms, the standardized hypnosis treatment has a more widespread central effect compared to education. The brain effects are seen during the expectation of rectal discomfort, but not during the experience of aversive rectal distensions. These findings are consistent with a HYP-induced reduction in pain expectation, rather than pain perception
|
|
| 10. |
- Schoemaker, Minouk J., et al.
(författare)
-
Adult weight change and premenopausal breast cancer risk : A prospective pooled analysis of data from 628,463 women
- 2020
-
Ingår i: International Journal of Cancer. - : John Wiley & Sons. - 0020-7136 .- 1097-0215. ; 147:5, s. 1306-1314
-
Tidskriftsartikel (refereegranskat)abstract
- Early-adulthood body size is strongly inversely associated with risk of premenopausal breast cancer. It is unclear whether subsequent changes in weight affect risk. We pooled individual-level data from 17 prospective studies to investigate the association of weight change with premenopausal breast cancer risk, considering strata of initial weight, timing of weight change, other breast cancer risk factors and breast cancer subtype. Hazard ratios (HR) and 95% confidence intervals (CI) were obtained using Cox regression. Among 628,463 women, 10,886 were diagnosed with breast cancer before menopause. Models adjusted for initial weight at ages 18-24 years and other breast cancer risk factors showed that weight gain from ages 18-24 to 35-44 or to 45-54 years was inversely associated with breast cancer overall (e.g., HR per 5 kg to ages 45-54: 0.96, 95% CI: 0.95-0.98) and with oestrogen-receptor(ER)-positive breast cancer (HR per 5 kg to ages 45-54: 0.96, 95% CI: 0.94-0.98). Weight gain from ages 25-34 was inversely associated with ER-positive breast cancer only and weight gain from ages 35-44 was not associated with risk. None of these weight gains were associated with ER-negative breast cancer. Weight loss was not consistently associated with overall or ER-specific risk after adjusting for initial weight. Weight increase from early-adulthood to ages 45-54 years is associated with a reduced premenopausal breast cancer risk independently of early-adulthood weight. Biological explanations are needed to account for these two separate factors.
|
|
| 11. |
- Wu, You, et al.
(författare)
-
Dairy foods, calcium, and risk of breast cancer overall and for subtypes defined by estrogen receptor status : a pooled analysis of 21 cohort studies
- 2021
-
Ingår i: American Journal of Clinical Nutrition. - : Oxford University Press. - 0002-9165 .- 1938-3207. ; 114:2, s. 450-461
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Epidemiologic studies examining the relations between dairy product and calcium intakes and breast cancer have been inconclusive, especially for tumor subtypes. Objective: To evaluate the associations between intakes of specific dairy products and calcium and risk of breast cancer overall and for subtypes defined by estrogen receptor (ER) status. Method: We pooled the individual-level data of over 1 million women who were followed for a maximum of 8-20 years across studies. Associations were evaluated for dairy product and calcium intakes and risk of incident invasive breast cancer overall (n = 37,861 cases) and by subtypes defined by ER status. Study-specific multivariable hazard ratios (HRs) were estimated and then combined using random-effects models. Results: Overall, no clear association was observed between the consumption of specific dairy foods, dietary (from foods only) calcium, and total (from foods and supplements) calcium, and risk of overall breast cancer. Although each dairy product showed a null or very weak inverse association with risk of overall breast cancer (P, test for trend >0.05 for all), differences by ER status were suggested for yogurt and cottage/ricotta cheese with associations observed for ER-negative tumors only (pooled HR = 0.90, 95% CI: 0.83, 0.98 comparing >= 60 g/d with <1 g/d of yogurt and 0.85, 95% CI: 0.76, 0.95 comparing >= 25 g/d with <1 g/d of cottage/ricotta cheese). Dietary calcium intake was only weakly associated with breast cancer risk (pooled HR = 0.98, 95% CI: 0.97, 0.99 per 350 mg/d). Conclusion: Our study shows that adult dairy or calcium consumption is unlikely to associate with a higher risk of breast cancer and that higher yogurt and cottage/ricotta cheese intakes were inversely associated with the risk of ER-negative breast cancer, a less hormonally dependent subtype with poor prognosis. Future studies on fermented dairy products, earlier life exposures, ER-negative breast cancer, and different racial/ethnic populations may further elucidate the relation.
|
|
| 12. |
- Bonfiglio, Ferdinando, et al.
(författare)
-
GWAS of stool frequency provides insights into gastrointestinal motility and irritable bowel syndrome
- 2021
-
Ingår i: Cell Genomics. - Cambridge, MA, United States : Elsevier. - 2666-979X. ; 1:3
-
Tidskriftsartikel (refereegranskat)abstract
- Gut dysmotility is associated with constipation, diarrhea, and functional gastrointestinal disorders like irritable bowel syndrome (IBS), although its molecular underpinnings are poorly characterized. We studied stool frequency (defined by the number of bowel movements per day, based on questionnaire data) as a proxy for gut motility in a GWAS meta-analysis including 167,875 individuals from UK Biobank and four smaller population-based cohorts. We identify 14 loci associated with stool frequency (p ≤ 5.0 × 10-8). Gene set and pathway analyses detected enrichment for genes involved in neurotransmitter/neuropeptide signaling and preferentially expressed in enteric motor neurons controlling peristalsis. PheWAS identified pleiotropic associations with dysmotility syndromes and the response to their pharmacological treatment. The genetic architecture of stool frequency correlates with that of IBS, and UK Biobank participants from the top 1% of stool frequency polygenic score distribution were associated with 5× higher risk of IBS with diarrhea. These findings pave the way for the identification of actionable pathological mechanisms in IBS and the dysmotility syndromes.
|
|
| 13. |
|
|
| 14. |
|
|
| 15. |
- Koushik, Anita, et al.
(författare)
-
Intake of the major carotenoids and the risk of epithelial ovarian cancer in a pooled analysis of 10 cohort studies
- 2006
-
Ingår i: International Journal of Cancer. - Harvard Univ, Sch Publ Hlth, Dept Nutr, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02115 USA. Brigham & Womens Hosp, Dept Med, Channing Lab, Boston, MA 02115 USA. Harvard Univ, Sch Med, Boston, MA 02115 USA. Harvard Univ, Ctr Canc Prevent, Boston, MA 02115 USA. Harvard Univ, Sch Publ Hlth, Dept Biostat, Boston, MA 02115 USA. Univ Minnesota, Sch Publ Hlth, Div Epidemiol & Community Hlth, Minneapolis, MN USA. Brigham & Womens Hosp, Dept Med, Div Prevent Med, Boston, MA 02115 USA. SUNY Buffalo, Dept Social & Prevent Med, Buffalo, NY USA. TNO, Qual Life, Dept Food & Chem Risk Anal, NL-3700 AJ Zeist, Netherlands. Karolinska Inst, Natl Inst Environm Med, Div Nutrit Epidemiol, Stockholm, Sweden. NCI, Div Canc Epidemiol & Genet, NIH, Bethesda, MD 20892 USA. Amer Canc Soc, Epidemiol & Surveillance Res, Atlanta, GA 30329 USA. Univ Toronto, Fac Med, Dept Publ Hlth Sci, Toronto, ON, Canada. Albert Einstein Coll Med, Dept Epidemiol & Populat Hlth, Bronx, NY 10467 USA. Maastricht Univ, NUTRIM, Dept Epidemiol, Maastricht, Netherlands. : WILEY. - 0020-7136 .- 1097-0215. ; 119:9, s. 2148-2154
-
Tidskriftsartikel (refereegranskat)abstract
- Carotenoids, found in fruits and vegetables, have the potential to protect against cancer because of their properties, including their functions as precursors to vitamin A and as antioxidants. We examined the associations between intakes of alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein/zeaxanthin and lycopene and the risk of invasive epithelial ovarian cancer. The primary data from 10 prospective cohort studies in North America and Europe were analyzed and then pooled. Carotenoid intakes were estimated from a validated food frequency questionnaire administered at baseline in each study. Study-specific relative risks (RR) were estimated using the Cox proportional hazards model and then combined using a random-effects model. Among 521,911 women, 2,012 cases of ovarian cancer occurred during a follow-up of 7-22 years across studies. The major carotenoids were not significantly associated with the risk of ovarian cancer. The pooled multivariate RRs (95% confidence intervals) were 1.00 (0.95-1.05) for a 600 mu g/day increase in alpha-carotene intake, 0.96 (0.93-1.03) for a 2,500 mu g/day increase in beta-carotene intake, 0.99 (0.97-1.02) for a 100 mu g/day increase in beta-cryptoxanthin intake, 0.98 (0.94-1.03) for a 2,500 mu g/day increase in lutein/zeaxanthin intake and 1.01 (0.97-1.05) for a 4,000 mu g/day increase in lycopene intake. These associations did not appreciably differ by study (p-values, tests for between-studies heterogeneity > 0.17). Also, the observed associations did not vary substantially by subgroups of the population or by histological type of ovarian cancer. These results suggest that consumption of the major carotenoids during adulthood does not play a major role in the incidence of ovarian cancer. (c) 2006 Wiley-Liss, Inc.
|
|
| 16. |
- Zhang, Xuehong, et al.
(författare)
-
Risk of Colon Cancer and Coffee, Tea, and Sugar-Sweetened Soft Drink Intake : Pooled Analysis of Prospective Cohort Studies
- 2010
-
Ingår i: Journal of the National Cancer Institute. - : OXFORD UNIV PRESS INC. - 0027-8874 .- 1460-2105. ; 102:11, s. 771-783
-
Tidskriftsartikel (refereegranskat)abstract
- The relationships between coffee, tea, and sugar-sweetened carbonated soft drink consumption and colon cancer risk remain unresolved. We investigated prospectively the association between coffee, tea, and sugar-sweetened carbonated soft drink consumption and colon cancer risk in a pooled analysis of primary data from 13 cohort studies. Among 731 441 participants followed for up to 6-20 years, 5604 incident colon cancer case patients were identified. Study-specific relative risks (RRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazards models and then pooled using a random-effects model. All statistical tests were two-sided. Compared with nonconsumers, the pooled multivariable relative risks were 1.07 (95% CI = 0.89 to 1.30, P-trend = .68) for coffee consumption greater than 1400 g/d (about six 8-oz cups) and 1.28 (95% CI = 1.02 to 1.61, P-trend = .01) for tea consumption greater than 900 g/d (about four 8-oz cups). For sugar-sweetened carbonated soft drink consumption, the pooled multivariable relative risk comparing consumption greater than 550 g/d (about 18 oz) to nonconsumers was 0.94 (95% CI = 0.66 to 1.32, P-trend = .91). No statistically significant between-studies heterogeneity was observed for the highest category of each beverage consumed (P > .20). The observed associations did not differ by sex, smoking status, alcohol consumption, body mass index, physical activity, or tumor site (P > .05). Drinking coffee or sugar-sweetened carbonated soft drinks was not associated with colon cancer risk. However, a modest positive association with higher tea consumption is possible and requires further study.
|
|
| 17. |
- Bednarska, Olga, et al.
(författare)
-
Vasoactive Intestinal Polypeptide and Mast Cells Regulate Increased Passage of Colonic Bacteria in Patients With Irritable Bowel Syndrome
- 2017
-
Ingår i: Gastroenterology. - : W B SAUNDERS CO-ELSEVIER INC. - 0016-5085 .- 1528-0012. ; 153:4, s. 948-
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND amp; AIMS: Irritable bowel syndrome (IBS) is associated with intestinal dysbiosis and symptoms of IBS develop following gastroenteritis. We aimed to study the passage of live bacteria through the colonic epithelium, and determine the role of mast cells (MCs) and vasoactive intestinal polypeptide (VIP) in barrier regulation in IBS and healthy individuals. METHODS: Colon biopsies from 32 women with IBS and 15 age-matched healthy women (controls) were mounted in Ussing chambers; we measured numbers of fluorescently labeled Escherichia coli HS and Salmonella typhimurium that passed through from the mucosal side to the serosal side of the tissue. Some biopsies were exposed to agents that block the VIP receptors (VPAC1 and VPAC2) or MCs. Levels of VIP and tryptase were measured in plasma and biopsy lysates. Number of MCs and MCs that express VIP or VIP receptors were quantified by immunofluorescence. Biopsies from an additional 5 patients with IBS and 4 controls were mounted in chambers and Salmonella were added; we studied passage routes through the epithelium by transmission electron microscopy and expression of tight junctions by confocal microscopy. RESULTS: In colon biopsies from patients with IBS, larger numbers of E coli HS and S typhimurium passed through the epithelium than in biopsies from controls (P amp;lt;.0005). In transmission electron microscopy analyses, bacteria were found to cross the epithelium via only the transcellular route. Bacterial passage was reduced in biopsies from patients with IBS and controls after addition of antibodies against VPACs or ketotifen, which inhibits MCs. Plasma samples from patients with IBS had higher levels of VIP than plasma samples from controls. Biopsies from patients with IBS had higher levels of tryptase, larger numbers of MCs, and a higher percentage of MCs that express VPAC1 than biopsies from controls. In biopsies from patients with IBS, addition of Salmonella significantly reduced levels of occludin; subsequent addition of ketotifen significantly reversed this effect. CONCLUSIONS: We found that colonic epithelium tissues from patients with IBS have increased translocation of commensal and pathogenic live bacteria compared with controls. The mechanisms of increased translocation include MCs and VIP.
|
|
| 18. |
- Fortelius, Mikael, et al.
(författare)
-
The Origin and Early History of NOW as It Happened
- 2023
-
Ingår i: Evolution of Cenozoic Land Mammal Faunas and Ecosystems: 25 years of the NOW database of fossil mammals.. - : Springer. ; , s. 7-32
-
Bokkapitel (refereegranskat)abstract
- The NOW database of fossil mammals came to be through a confluence of several initiatives spanning multiple decades. The first public version of NOW database was released in 1996 and the first Advisory Board was established the year after. Originally, NOW stood for Neogene of the Old World but with the gradual expansion of the database the acronym was eventually reassigned to stand for New and Old Worlds. The structure of what would become NOW was originally cloned from the ETE database of the Smithsonian Institution and the first NOW version accessible over the internet was a node of the ETE database. The first standalone, online version of NOW was launched in 2005 and the first formal steering group was established in 2009. During its existence, NOW has been funded, directly or indirectly, by several organizations but fundamentally it has always been an unfunded community effort, dependent on voluntary work by the participants.
|
|
| 19. |
|
|
| 20. |
- Haziot, Susanna V., et al.
(författare)
-
Traveling Water Waves - The Ebb and Flow of Two Centuries
- 2022
-
Ingår i: Quarterly of Applied Mathematics. - : American Mathematical Society (AMS). - 0033-569X .- 1552-4485. ; 80:2, s. 317-401
-
Tidskriftsartikel (refereegranskat)abstract
- This survey covers the mathematical theory of steady water waves with an emphasis on topics that are at the forefront of current research. These areas include: variational characterizations of traveling water waves; analytical and numerical studies of periodic waves with critical layers that may overhang; existence, nonexistence, and qualitative theory of solitary waves and fronts; traveling waves with localized vorticity or density stratification; and waves in three dimensions.
|
|
| 21. |
- Icenhour, Adriane, et al.
(författare)
-
Brain functional connectivity is associated with visceral sensitivity in women with Irritable Bowel Syndrome
- 2017
-
Ingår i: NeuroImage. - : ELSEVIER SCI LTD. - 2213-1582. ; 15, s. 449-457
-
Tidskriftsartikel (refereegranskat)abstract
- Increased perception of visceral stimuli is a key feature of Irritable Bowel Syndrome (IBS). While altered resting-state functional connectivity (rsFC) has been also reported in IBS, the relationship between visceral hypersensitivity and aberrant rsFC is unknown. We therefore assessed rsFC within the salience, sensorimotor and default mode networks in patients with and without visceral hypersensitivity and in healthy controls (HCs). An exploratory resting-state functional magnetic resonance imaging study was performed in 41 women with IBS and 20 HCs. Group independent component analysis was used to derive intrinsic brain networks. Rectal thresholds were determined and patients were subdivided into groups with increased (hypersensitive IBS, N = 21) or normal (normosensitive IBS, N= 20) visceral sensitivity. Between-group comparisons of rsFC were carried-out using region-of-interest analyses and peak rsFC values were extracted for correlational analyses. Relative to normosensitive IBS, hypersensitive patients showed increased positive rsFC of pregenual anterior cingulate cortex and thalamus within the salience network and of posterior insula within the sensorimotor network. When compared to both hypersensitive IBS and HCs, normosensitive IBS showed decreased positive rsFC of amygdala and decreased negative rsFC in dorsal anterior insula within the DMN. DMN and sensorimotor network rsFC were associated with rectal perception thresholds, and rsFC in posterior insula was correlated with reported symptom severity in IBS. Our exploratory findings suggest that visceral sensitivity in IBS is related to changes in FC within resting-state networks associated with interoception, salience and sensory processing. These alterations may play an important role in hypervigilance and hyperalgesia in IBS.
|
|
| 22. |
|
|
| 23. |
|
|
| 24. |
|
|
| 25. |
- Lowén, Mats, et al.
(författare)
-
Effect of hypnotherapy and educational intervention on brain response to visceral stimulus in the irritable bowel syndrome
- 2013
-
Ingår i: Alimentary Pharmacology and Therapeutics. - : Wiley-Blackwell. - 0269-2813 .- 1365-2036. ; 37:12, s. 1184-1197
-
Tidskriftsartikel (refereegranskat)abstract
- Background Gut-directed hypnotherapy can reduce IBS symptoms, but the mechanisms underlying this therapeutic effect remain unknown. Aim To determine the effect of hypnotherapy and educational intervention on brain responses to cued rectal distensions in IBS patients. Methods Forty-four women with moderate-to-severe IBS and 20 healthy controls (HCs) were included. Blood oxygen level dependent (BOLD) signals were measured by functional Magnetic Resonance Imaging (fMRI) during expectation and delivery of high- (45mmHg) and low-intensity (15mmHg) rectal distensions. Twenty-five patients were assigned to hypnotherapy (HYP) and 16 to educational intervention (EDU). Thirty-one patients completed treatments and posttreatment fMRI. Results Similar symptom reduction was achieved in both groups. Clinically successful treatment (all responders) was associated with significant BOLD attenuation during high-intensity distension in the dorsal and ventral anterior insula (cluster size 142, P=0.006, and cluster size 101, P=0.005 respectively). Moreover HYP responders demonstrated a prepost treatment BOLD attenuation in posterior insula (cluster sizes 59, P=0.05) while EDU responders had a BOLD attenuation in prefrontal cortex (cluster size 60, P=0.05). Prepost differences for expectation conditions were almost exclusively seen in the HYP group. Following treatment, the brain response to distension was similar to that observed in HCs, suggesting that the treatment had a normalising effect on the central processing abnormality of visceral signals in IBS. Conclusions The abnormal processing and enhanced perception of visceral stimuli in IBS can be normalised by psychological interventions. Symptom improvement in the treatment groups may be mediated by different brain mechanisms. Clinical trial number: NCT01815164.
|
|
| 26. |
- Simon, Rozalyn, 1979-, et al.
(författare)
-
Magnetotactic bacteria from the human gut microbiome associated with orientation and navigation regions of the brain
- 2021
-
Ingår i: Journal of Oceanology and Limnology. - : Springer Nature. - 2096-5508 .- 2523-3521. ; 39:6, s. 2044-2052
-
Tidskriftsartikel (refereegranskat)abstract
- Magnetotactic bacteria (MTB), ubiquitous in soil and fresh and saltwater sources have been identified in the microbiome of humans and many animals. MTB endogenously produce magnetic nanocrystals enabling them to orient and navigate along geomagnetic fields. Similar magnetite deposits have been found throughout the tissues of the human brain, including brain regions associated with orientation such as the cerebellum and hippocampus, the origins of which remain unknown. Speculation over the role and source of MTB in humans, as well as any association with the brain, remain unanswered. We performed a metagenomic analysis of the gut microbiome of 34 healthy females as well as grey matter volume analysis in magnetite-rich brain regions associated with orientation and navigation with the goal of identifying specific MTB that could be associated with brain structure in orientation and navigation regions. We identified seven MTB in the human gut microbiome: Magnetococcus marinus, Magnetospira sp. QH-2, Magnetospirillum magneticum, Magnetospirillum sp. ME-1, Magnetospirillum sp. XM-1, Magnetospirillum gryphiswaldense, and Desulfovibrio magneticus. Our preliminary results show significant negative associations between multiple MTB with bilateral flocculonodular lobes of the cerebellum and hippocampus (adjusted for total intracranial volume, uncorrected P<0.05). These findings indicate that MTB in the gut are associated with grey matter volume in magnetite-rich brain regions related to orientation and navigation. These preliminary findings support MTB as a potential biogenic source for brain magnetite in humans. Further studies will be necessary to validate and elucidate the relationship between these bacteria, magnetite concentrations, and brain function.
|
|
| 27. |
|
|
| 28. |
|
|
| 29. |
- Walter, Susanna A, et al.
(författare)
-
Positive Allosteric Modulator of GABA Lowers BOLD Responses in the Cingulate Cortex
- 2016
-
Ingår i: PLOS ONE. - San Francisco, CA, United States : Public Library of Science. - 1932-6203. ; 11:3
-
Tidskriftsartikel (refereegranskat)abstract
- Knowledge about the neural underpinnings of the negative blood oxygen level dependent (BOLD) responses in functional magnetic resonance imaging (fMRI) is still limited. We hypothesized that pharmacological GABAergic modulation attenuates BOLD responses, and that blood concentrations of a positive allosteric modulator of GABA correlate inversely with BOLD responses in the cingulate cortex. We investigated whether or not pure task-related negative BOLD responses were co-localized with pharmacologically modulated BOLD responses. Twenty healthy adults received either 5 mg diazepam or placebo in a double blind, randomized design. During fMRI the subjects performed a working memory task. Results showed that BOLD responses in the cingulate cortex were inversely correlated with diazepam blood concentrations; that is, the higher the blood diazepam concentration, the lower the BOLD response. This inverse correlation was most pronounced in the pregenual anterior cingulate cortex and the anterior mid-cingulate cortex. For subjects with diazepam plasma concentration > 0.1 mg/L we observed negative BOLD responses with respect to fixation baseline. There was minor overlap between cingulate regions with task-related negative BOLD responses and regions where the BOLD responses were inversely correlated with diazepam concentration. We interpret that the inverse correlation between the BOLD response and diazepam was caused by GABA-related neural inhibition. Thus, this study supports the hypothesis that GABA attenuates BOLD responses in fMRI. The minimal overlap between task-related negative BOLD responses and responses attenuated by diazepam suggests that these responses might be caused by different mechanisms.
|
|
| 30. |
- Walter, Susanna A., et al.
(författare)
-
Pre-experimental stress in patients with irritable bowel syndrome : high cortisol values already before symptom provocation with rectal distensions
- 2006
-
Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 18:12, s. 1069-1077
-
Tidskriftsartikel (refereegranskat)abstract
- Stress is known to affect symptoms of irritable bowel syndrome (IBS) probably by an alteration of visceral sensitivity. We studied the impact of maximal tolerable rectal distensions on cortisol levels in patients with IBS, chronic constipation and controls, and evaluated the effect of the experimental situation per se. In twenty-four IBS patients, eight patients with chronic constipation and 15 controls salivary cortisol was measured before and after repetitive maximal tolerable rectal balloon distensions and at similar times in their usual environment. Rectal sensitivity thresholds were determined. IBS patients but not controls and constipation patients had higher cortisol levels both before and after the experiment compared with similar times on an ordinary day in their usual environment (P = 0.0034 and 0.0002). There was no difference in salivary cortisol level before compared with after rectal distensions. The IBS patients had significantly lower thresholds for first sensation, urge and maximal tolerable distension than controls (P = 0.0247, 0.0001 and <0.0001) and for urge and maximal tolerable distension than patients with constipation (P = 0.006 and 0.013). IBS patients may be more sensitive to expectancy stress than controls and patients with constipation according to salivary cortisol. Rectal distensions were not associated with a further significant increase in cortisol levels.
|
|
| 31. |
- Walter, Susanna A, et al.
(författare)
-
Prospective Diary Evaluation of Unexplained Abdominal Pain and Bowel Dysfunction : A Population-Based Colonoscopy Study
- 2011
-
Ingår i: Digestive Diseases and Sciences. - : Springer. - 0163-2116 .- 1573-2568. ; 56:5, s. 1444-1451
-
Tidskriftsartikel (refereegranskat)abstract
- INTRODUCTION: Diagnostic criteria for irritable bowel syndrome (IBS) have not been validated by prospective symptom diary. We investigated the bowel patterns in community subjects with and without non-organic abdominal pain, and compared the symptoms with subjects fulfilling the Rome II criteria (IBS). METHODS: From the Swedish population register, a random sample completed an abdominal symptom questionnaire. Responders were subsequently invited for a clinical evaluation and offered a colonoscopy regardless of whether they had abdominal symptoms or not. A total of 268 subjects underwent colonoscopy, clinical evaluation by gastroenterologist, laboratory investigations, and completed the Rome questionnaire and prospective gastrointestinal (GI) symptom diaries for 1 week. Twenty-three subjects of 268 were excluded due to organic GI disease. RESULTS: Subjects recorded 2,194 bowel movements and 370 abdominal pain episodes on 1,504 days. Subjects with pain in the diary (n = 81) had higher stool frequency (P = 0.01), more urgency (P = 0.0002), feelings of incomplete evacuation (P = 0.0002), nausea (P = 0.0009), and abdominal bloating (P = 0.0005) than subjects without pain (n = 151). Twenty-eight subjects (12%) fulfilled the Rome II criteria for IBS. Together, they had 96 pain episodes but only 4% were improved by defecation; 29% of the pain episodes started or worsened after a meal. Subjects with IBS and other subjects with non-organic abdominal pain (n = 64) exhibited no differences in terms of the proportions of pain episodes improved by defecation, bloating, stool frequency, consistency, or defecatory symptoms. CONCLUSIONS: Current criteria for IBS that rely on recall of the relationship between abdominal pain and bowel disturbance may overcall this association when measured prospectively.
|
|
| 32. |
- Walter, Susanna A., et al.
(författare)
-
Sympathetic (electrodermal) activity during repeated maximal rectal distensions in patients with irritable bowel syndrome and constipation
- 2008
-
Ingår i: Neurogastroenterology and Motility. - : Wiley. - 1350-1925 .- 1365-2982. ; 20:1, s. 43-52
-
Tidskriftsartikel (refereegranskat)abstract
- Irritable bowel syndrome (IBS) is associated with visceral hypersensitivity, stress and autonomic dysfunction. Sympathetic activity during repeated events indicates excitatory or inhibitory mechanisms such as sensitization or habituation. We investigated skin conductance (SC) during repetitive rectal distensions at maximal tolerable pressure in patients with IBS and chronic constipation. Twenty-seven IBS patients, 13 constipation patients and 18 controls underwent two sets of isobaric rectal distensions. First, maximal tolerable distension was determined and then it was repeated five times. Skin conductance was measured continuously. Subjective symptom assessment remained steady in all groups. The baseline values of SC were higher in IBS patients than in patients with constipation and significantly lower in constipation patients than in controls. The maximal SC response to repetitive maximal distensions was higher in IBS patients compared with constipation patients. The amplitude of the initial SC response decreased successively with increased number of distensions in patients with IBS and constipation but not in controls. Irritable bowel syndrome and constipation patients habituated to maximal repetitive rectal distensions with decreasing sympathetic activity. Irritable bowel syndrome patients had higher sympathetic reactivity and baseline activity than constipation patients. A lower basal SC in constipation patients compared with controls suggests an inhibition of the sympathetic drive in constipation patients.
|
|
| 33. |
- Walter, Susanna, et al.
(författare)
-
Anorectal function in patients with collagenous colitis in active and clinically quiescent phase, in comparison with healthy controls
- 2010
-
Ingår i: Neurogastroenterology and Motility. - : Blackwell Publishing Ltd. - 1350-1925 .- 1365-2982. ; 22:5, s. 534-
-
Tidskriftsartikel (refereegranskat)abstract
- Background Collagenous colitis (CC) is characterized by chronic watery diarrhea, a macroscopically normal colonic mucosa but typical microscopic inflammation. Chronic mucosal inflammation of the colon and rectum has earlier been associated with altered visceral sensitivity, but anorectal function has never been reported in cases of CC. Methods Fifteen patients with CC in active phase recorded their symptoms. The severity of inflammation was determined in mucosal biopsies. Anorectal function was assessed and compared with that of 15 healthy volunteers of corresponding age and matched for gender. After 6 weeks of budesonide treatment when the patients were in clinical remission anorectal function was re-assessed. Key Results All patients had inflammation also in rectum. Patients in active phase had, during rectal balloon distension a higher rectal sensory threshold for the feeling of first sensation, compared with controls (P = 0.02). There were no differences in rectal sensory threshold for the feeling of urgency or maximum distension, between patients with CC in active phase and healthy controls. Rectal volume at first sensation was significantly greater in patients than in controls (P = 0.02), but there were no differences at urgency or maximum distension. Twelve of 15 patients completed 6 weeks of budesonide treatment and all went into clinical remission. No differences in anorectal function were measured when patients had active disease, compared with clinical remission. Conclusions andamp; Inferences Collagenous colitis was not associated with rectal hypersensitivity or disturbed anal function despite rectal inflammation. On the contrary, the sensation threshold for light rectal pressure was elevated in patients with active CC.
|
|
| 34. |
- Walter, Susanna, et al.
(författare)
-
Su2113 High-Intense Rectal Urgency and Its Representation in the Brain
- 2013
-
Konferensbidrag (refereegranskat)abstract
- Background: Several brain imaging studies have demonstrated that visceral distensions activate the insular cortex but there is limited knowledge about which subregions of the insula underpin the feeling of rectal urgency. An isobaric rectal balloon distension can be subdivided into the inflation phase when pressure is rising (rise) and a stable phase, when the pressure is constant. The rise phase is characterized by a more distinct sensation of urgency (Akervall et al., 1988). We aimed to study the BOLD response during the rise phase of a standardized rectal distension in subregions of the insula, in healthy controls.Method:Twenty right-handed female healthy volunteers (mean age 32.2 yrs, range 21-54) were included. Rectal pressure sensory thresholds were determined before functional Magnetic Resonance Imaging (fMRI) while the subjects were placed in the MR scanner. Blood Oxygen Level Dependent (BOLD) signals were measured during the rise periods (6.6-7.2 sec) of 20 rectal distensions (45mmHg). Regions of interest (ROIs) included 10 insula subregions: Left (L) and right (R) anterior ventral, anterior dorsal, posterior ventral, posterior dorsal and mid insula. Results were reported as significant if peak p-value were, 0.05 with familywise error (FWE) correction in the ROIs.Results: The mean values for rectal sensory thresholds for first sensation, first sensation of urgency and maximum tolerable distension were 16 mmHg (SD 3.9), 28mmHg (SD 6.2) and 55 mmHg (SD 12.3), respectively. Complete fMRI data were available from 18 subjects. The rise period of the rectal distension generated significant BOLD activation in the right hemisphere in the anterior dorsal, anterior ventral, mid and posterior ventral parts of the insula. On the left side BOLD activity was generated in mid, posterior ventral and posterior dorsal parts of the insula but not in the anterior insula. Akervall S et al, 1988, Manovolumetry: A new method for investigation of anorectal function. Gut 29:614-623.
|
|
| 35. |
- Witt, Suzanne Tyson, 1979-, et al.
(författare)
-
Interactions between gut permeability and brain structure and function in health and irritable bowel syndrome
- 2019
-
Ingår i: NeuroImage. - : Elsevier. - 2213-1582. ; 21
-
Tidskriftsartikel (refereegranskat)abstract
- Changes in brain-gut interactions have been implicated in the pathophysiology of chronic visceral pain in irritable bowel syndrome (IBS). Different mechanisms of sensitization of visceral afferent pathways may contribute to the chronic visceral pain reports and associated brain changes that characterize IBS. They include increased gut permeability and gut associated immune system activation, and an imbalance in descending pain inhibitory and facilitatory mechanisms. In order to study the involvement of these mechanisms, correlations between gut epithelial permeability and live bacterial passage, and structural and functional brain connectivity were measured in women with moderate-to-severe IBS and healthy women. The relationships between gut permeability and functional and anatomical connectivity were significantly altered in IBS compared with the healthy women. IBS participants with lower epithelial permeability reported increased IBS symptoms, which was associated with increased functional and structural connectivity in endogenous pain facilitation regions. The findings suggest that relationships between gut permeability and the brain are significantly altered in IBS and suggest the existence of IBS subtypes based on these interactions.
|
|
