Effect of repeated Campylobacter jejuni infection on gut flora and mucosal defense in a rat model of post infectious functional and microbial bowel changes

BACKGROUND

Campylobacter jejuni infection is a leading cause of gastroenteritis and post infectious irritable bowel syndrome (PI-IBS). Unanswered questions include the role of cytokines, effects on gut flora, and why IBS is not more prevalent in countries with higher gastroenteritis rates. Therefore, we determined the effects of early and repeat C. jejuni infections on post infectious phenotypes, gut flora, and cytokine levels in a rat model of functional bowel and microbial changes.

METHODS

Sprague-Dawley rats were gavaged with 10(8)  cfu C. jejuni as juveniles and again as adults (J+/A+), as adults only (J-/A+), or vehicle (controls). Stool consistency during acute colonization, post infectious stool wet weight, total bacteria and Methanobrevibacter smithii levels in bowel segments, and ileal cytokines were evaluated.

KEY RESULTS

C. jejuni colonization was longer for first exposures as juveniles (43.4 ± 1.7 days) vs. adults (30.4 ± 3.5 days) (P < 0.01) and shortest for second exposures (10.5 ± 1.7 days, P < 0.05). Small intestinal bacterial overgrowth (SIBO) was more prevalent in J+/A+ (47%) than J-/A+ rats (26%) (P = 0.019), but J-/A+ rats had greater stool consistency alterations (P < 0.01). Ileal β-defensin 2, TLR-4, IL-8, and β-defensin 6 levels were increased in J-/A+ rats and further increased in J+/A+ rats; TNF-α was highest and IL6 lowest in J-/A+ rats. Total bacteria increased, and M. smithii decreased, with successive infections.

CONCLUSIONS & INFERENCES

We conclude that C. jejuni infection results in long-term alterations in small bowel flora, including methanogens. Mucosal defense mediators appear related to the number of infections, but not to SIBO development or the development of functional bowel phenotypes.

The use of Pillcam Colon in assessing mucosal inflammation in ulcerative colitis: a multicenter study

BACKGROUND AND STUDY AIM

Treatment of ulcerative colitis should be tailored to the severity of colonic inflammation, which in the past has been gauged mainly by clinical features and biochemical parameters. Recently, mucosal healing has been proposed as a standard to guide therapy. The aim of this multicenter study was to test whether mucosal appearance, as reported by colon capsule endoscopy (CCE), can be used to differentiate active from inactive ulcerative colitis.

PATIENTS AND METHODS

Adult patients from Hong Kong, Singapore, and Taiwan who were suspected or known to have ulcerative colitis were included in this prospective study. CCE and conventional optical colonoscopy were offered to these patients on the same day after receiving standard bowel preparation. The primary endpoint was the accuracy of CCE in assessing colonic inflammation (defined as the presence of ulcers, erythema, erosions, edema, exudates in mucosa), using optical colonoscopy as the gold standard.

RESULTS

At total of 100 patients (42 females; median age 50 years; range 22 - 68 years) were enrolled. Four cases were excluded from the analysis due to technical failure or slow transit of the capsule. In nine patients, the capsule was not excreted within 8.5 hours and required retrieval during colonoscopy. The sensitivity of CCE to detect active colonic inflammation was 89 % (95 % confidence interval [CI] 80 - 95) and specificity was 75 % (95 %CI 51 - 90). The positive and negative predictive values of CCE for colonic inflammation were 93 % (95 %CI 84 - 97) and 65 % (95 %CI 43 - 83), respectively. No serious adverse event related to the CCE procedure or preparation was reported.

CONCLUSION

CCE is a safe procedure to monitor mucosal healing in ulcerative colitis. However, at this stage, CCE cannot be recommended to replace conventional colonoscopy in the management of this condition.

Genetic and environmental relationships between Framingham Risk Score and adiposity measures in Koreans: the Healthy Twin study

BACKGROUND AND AIMS

We examined heritability and bivariate analyses for the Framingham Risk Score (FRS) and adiposity measures among Koreans.

METHODS AND RESULTS

We analysed the data from 2496 participants (962 men, 1534 women, age 30-74 years), including 1320 non-twin family members, 468 monozygotic (MZ) and 120 dizygotic (DZ) twin pairs, collected from the Healthy Twin study of Korea. Adiposity measurements comprised BMI, waist circumference (WC), waist-to-hip ratio and waist-to-height ratio (WHTR). Analyses were conducted using the Sequential Oligogenic Linkage Analysis Routines (SOLAR) package software. The co-twin control analyses shows that estimates of within-pair regression coefficients in the relationship between adiposity traits and FRS were attenuated for MZ twin pairs, relative to DZ twin pairs (0.11-0.26 vs. 0.60-0.71). The heritability estimate for FRS was 0.37, and the estimates for adiposity traits ranged from 0.45 to 0.63 (P < 0.001). Bivariate analysis revealed genetic correlations between FRS, and all of the adiposity traits ranged from 0.16 (for WHTR, P > 0.05) to 0.46 (for WC, P < 0.001). The common environmental correlations between FRS and each of the adiposity traits ranged from 0.43 to 0.66 (P < 0.001).

CONCLUSIONS

FRS and each of the obesity traits shared common genetic and environmental relationships. These findings support a pleiotropic action between genes associated with adiposity traits and FRS and a need of further investigations for identifying specific common environmental factors.

Genetic influence on bone mineral density in Korean twins and families: the healthy twin study

Bone mineral density (BMD), a representative marker of osteoporosis risk, is found to be highly heritable in this Korean study, which is very consistent with the findings in Western populations. This finding strongly supports that genetic factors are significant determinants of osteoporosis risk along with individual biological and behavioral factors.

INTRODUCTION

Although genetic factors are known to contribute significantly to variations in BMD in Western populations, such an association has not been fully evaluated in an Asian population. This study was conducted to determine the role of genetic factors on BMD in Korean population.

METHODS

The study participants were 2,728 men and women consisting of 497 monozygotic (MZ) twin pairs, 119 dizygotic (DZ) twin pairs, and 1,496 first-degree relatives from the Healthy Twin Study. BMD was measured using dual-energy X-ray absorptiometry. Quantitative genetic analysis based on a variance decomposition model was performed.

RESULTS

Age and the measured covariates accounted for 17~61% of the variation in BMD, depending on the sites of measurement. After accounting for the covariate effects, the heritability of BMD at the whole body, thoracic and lumbar spine, whole ribs, whole pelvis, whole arms, and whole legs were 0.76, 0.72, 0.73, 0.71, 0.51, and 0.75, respectively. The pair-wise correlation of BMD was the highest within MZ twin pairs, followed by DZ twin pairs, sibling pairs, and parents-child pairs. Cross-trait correlation analysis revealed a positive genetic correlation between BMDs at different sites, ranging from 0.80 (arm and leg BMD) to 0.50 (pelvis and arm BMD).

CONCLUSIONS

The high heritability of BMD in this Korean population similar to those found in Western populations and the significant common genetic basis between BMDs at different sites strongly supports a significant role of genetic determinants on the risk of osteoporosis.

The interfacial structure of water/protonated α-Al2O3 (11 ̅20) as a function of pH

Sum frequency vibrational spectroscopy (SFVS) was used to study the structure of the protonated α-Al(2)O(3) (11 ̅20), and water/α-Al(2)O(3) (11 ̅20) interfaces as a function of pH. By combining SFVS spectra with an oxygen-terminated model suggested by x-ray reflectivity, we are able to understand several details of the protonated α-Al(2)O(3) (11 ̅20) interface structure. For example, the spectral changes observed for the water/α-Al(2)O(3) (11 ̅20) interface with varying pH could be accounted for by the protonation/deprotonation of particular surface hydroxyls. Our spectra also indicate that the point of zero charge for this interface is at pH ~ 6.7.

P2-08-01: Impact of Aromatase Inhibitors on Background Parenchymal Enhancement and Amount of Fibroglandular Tissue on Breast MRI

Background: On breast MRI, background parenchymal enhancement (BPE) and volume of fibroglandular tissue (FGT) have been shown to reflect a patient's hormonal status. Tamoxifen has been shown to reduce mammographic breast density and may serve as an early predictor of response in the prevention setting (Cuzick, JNCI 2011). We have shown that adjuvant tamoxifen can reduce BPE in the unaffected breast in women with breast cancer. We hypothesize that aromatase inhibitor (AI) induced endocrine changes in breast tissue should also be evident and therefore we performed a study to evaluate whether adjuvant AI therapy influences BPE or amount of FGT in the contralateral breast.

Methods: An electronic medical record review identified 856 postmenopausal women with stage I-III breast cancer who had at least two breast MRIs and took adjuvant AI treatment. A retrospective chart review was conducted to select those patients without a history of prior tamoxifen or raloxifene treatment who had a MRI of the contralateral breast both before and during 6 to 12 months of AI treatment. After exclusion of all irradiated breasts, 168 women were eligible. MRIs were performed between August 1999 and June 2010. Two radiologists who were blind to AI treatment status, independently rated level of BPE and amount of FGT using categorical scales: BPE — Minimal, Mild, Moderate, Marked; FGT — Fatty, Scattered, Heterogeneously Dense, Dense (based on proposed BIRADS criteria for BPE and on ACR criteria for FGT). Blinded side-by-side direct comparison evaluated whether there was a category change between the two MRIs. A consensus was reached in cases of disagreement. The Wilcoxon signed-rank test was used to assess changes in rating categories for BPE and FGT between before and during AI breast MRIs. A waiver of authorization was granted by the institutional review board for this study.

Results: In this study 127/168 (76%) women were treated with anastrozole, 33/168 (20%) with letrozole and 8/168 (5%) with exemestane. Based on the blinded side-by-side comparison, a category (or more) decrease in BPE occurred during treatment with AIs (p&lt;0.0001). There was an overall shift from higher to lower degree of BPE in 35% (45/127) of the women taking anastrozole while a category increase occurred in only one woman (1%; p &lt;0.0001). A similar result was seen in the women taking letrozole [45% (15/33) had a decrease versus 3% (1/33) an increase; p=0.0003] and exemestane [25% (2/8) had a decrease versus 12.5% (1/8) an increase; p=0.50]. For FGT a category decrease occurred in 5% (6/127) of anastrozole users while no increase occurred [0% (0/127), p=0.016]. The respective numbers for letrozole were 3% (1/33) and 0% (0/33), and nobody on exemestane had a change in FGT.

Conclusions: After 6 to 12 months of treatment with adjuvant AIs, there was a statistically significant category (or more) decrease in BPE. BPE is more sensitive than FGT to changes in normal breast stroma that occur during adjuvant treatment with AIs and BPE may be a marker of anti-hormonal activity in the breasts.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-08-01.

Sex-specific relationships between adiposity and anthropometric measures and carotid intima-media thickness in Koreans: the Healthy Twin Study

BACKGROUND/OBJECTIVES

Increased adiposity, shorter stature, shorter leg length and carotid intima-media thickening are associated with cardiovascular (CV) disease. This study aimed to evaluate the sex-specific phenotypic and genetic associations between adiposity and anthropometric measures and carotid intima-media thickness (IMT).

SUBJECTS/METHODS

We measured IMT at common carotid artery (CCA-IMT), carotid bifurcation and internal carotid artery (ICA-IMT) using B-mode ultrasound, and adiposity and anthropometric measures, including body mass index (BMI), height, leg length, waist circumference (WC), waist-to-hip ratio and percentage of body fat; we also assessed conventional CV risk factors among 706 Korean adults from the Healthy Twin Study. The associations were analyzed using quantitative genetic and linear mixed analyses.

RESULTS

In linear mixed analyses, BMI and WC had independent associations with the IMT at CCA-IMT and ICA-IMT and CCA-IMT, respectively, after adjusting for age and conventional CV risk factors in men. By comparison, in women, adiposity and anthropometric measures were associated with carotid IMT only before adjusting for the covariates. In men, there were significant genetic correlations between BMI and CCA-IMT (ρ(G)=0.32±0.11), BMI and ICA-IMT (ρ(G)=0.35±0.11) and WC and ICA-IMT (ρ(G)=0.32±0.13) after adjusting for covariates, whereas in women the cross-trait genetic correlations were no longer significant after adjusting for the covariates.

CONCLUSIONS

In this Korean twins and families, we found sex-specific associations between adiposity and anthropometric measures and the IMT at each segment of the carotid artery, and BMI and WC in men can be indicators predicting carotid intima-media thickening regardless of age and CV risk factors.

Structure of The Diblock Co-Polywer Aggregates in Solution

We have employed a variety of scattering techniques to study the structure of diblock copolymer aggregates in solution The system of interest is an anionically prepared poly(styrene-isoprene) diblock copolymer (PS-PI) with well defined molecular weight and composition. When the diblock copolymer is added to decane, which dissolves the polyisoprene but not the polystyrene, we observe that polymeric micelles form at concentrations above a critical micellar concentration. The aggregation number is determined by light scattering and neutron scattering to be roughly 120. The micellar aggregate consists of a spherical polystyrene core with a mean radius of 105 A surrounded by a PI corona. The size distribution is quite narrow (<10%). The PS core is swollen with the solvent by roughly a factor of 2 in volume. By combining dynamic light scattering and SANS, we determined the thickness of the corona to be 50 A, which is 70% larger than the radius of gyration of a free PI chain of the same molecular weight in a good solvent. Furthermore, SANS measurements suggest that the aggregates form an ordered phase at the nominal cross-over concentration as it is expected for a highly functionalized star-branched macromolecules in solution.

Dyspepsia and irritable bowel syndrome in China: a population-based endoscopy study of prevalence and impact

BACKGROUND

Dyspepsia and irritable bowel syndrome (IBS) are common in Western populations.

AIM

To determine the epidemiology of dyspepsia and IBS in China.

METHODS

A representative sample of 18 000 adults from five regions of China were asked to complete the modified Rome II questionnaire; 20% were asked to complete the 36-item Short Form Health Survey (SF-36). Participants from Shanghai were invited to provide blood samples and undergo oesophago-gastroduodenoscopy. Odds ratios (ORs) and 95% confidence intervals (CIs) were determined using a multivariate logistic regression model.

RESULTS

The survey was completed by 16 091 individuals (response rate: 89.4%). Overall, 387 participants (2.4%) had dyspepsia and 735 (4.6%) had IBS. All SF-36 dimension scores were at least five points lower in individuals with than without dyspepsia or IBS (P < or = 0.001). In Shanghai, 1030 (32.7%) of the 3153 respondents agreed to endoscopy; neither dyspepsia nor IBS was found to be associated with reflux oesophagitis, peptic ulcer disease or Helicobacter pylori infection.

CONCLUSIONS

Prevalence estimates for dyspepsia and IBS in China are lower than in Western populations. In China, dyspepsia or IBS symptoms are generally not associated with underlying organic disease.

Combined effect of socioeconomic status, viral hepatitis, and lifestyles on hepatocelluar carcinoma risk in Korea

Background:

The independent and combined effects of socioeconomic status (SES), viral hepatitis, and other lifestyle factors on hepatocellular carcinoma (HCC) risk have not been investigated among Koreans.

Methods:

From the National Cancer Center Hospital, 207 HCC cases and 828 age- and gender-matched controls aged 30 years or older were recruited. Socio-demographic and behavioural risk factors were ascertained through personal interview, and infection with hepatitis B and C viruses was determined by their serologic markers. Multivariate logistic regression and synergy index methods were applied for statistical analysis.

Results:

HB surface antigen (HbsAg) and anti-HCV-positive rates were 149.3 and 185.1 times higher in cases than controls, respectively. Lifetime alcohol consumption (odds ratio: 2.96, 95% CI: 1.29–6.79), cigarette smoking (OR: 3.53, 95% CI: 1.31–9.52), and family income (OR: 17.07, 95% CI: 4.27–68.25) were independently associated with the risk of HCC in subjects with or without viral hepatitis. Synergistic interaction on HCC risk was observed between low income and HBsAg positivity (SI: 3.12, 95% CI: 1.51–6.47) and between low income and heavy alcohol intake (SI: 2.93, 95% CI: 1.24–6.89).

Conclusion:

The inverse association with SES suggests SES as an independent and synergistic predictor of HCC. Heavy alcohol intake also showed a combined effect with low SES on HCC risk.

Dietary habit and bone mineral density in Korean postmenopausal women

SUMMARY

Postmenopausal women were assessed to determine the association between dietary intake of various food groups and low bone mineral density. Among dietary factors, high consumption of protein-containing food and dairy products was associated with a reduced risk for low bone mineral density.

INTRODUCTION

There have been several studies regarding the correlation between bone mineral density and dietary intake. In this study, we assessed the association between dietary habit and low bone mineral density among Korean postmenopausal women.

METHODS

Bone mineral density of the lumbar spine was measured by dual energy X-ray absorptiometry in 2,501 subjects. A brief food frequency questionnaire, which included 16 food items, was used in this cross-sectional survey.

RESULTS

After adjusting for other risk factors related to low bone mineral density, a high intake frequency of protein-source food was associated with a lower risk for osteopenia (odds ratio (OR), 0.68; 95% confidence interval (CI), 0.54-0.87 for high vs. low intake frequency; p for trend, 0.02) and osteoporosis (OR, 0.76; 95% CI, 0.39-0.83 for high vs. low intake frequency; p for trend, 0.003), and a high intake frequency of dairy food was associated with a decreased risk for osteopenia (OR, 0.73; 95% CI, 0.57-0.94 for high vs. low intake frequency; p for trend, 0.018).

CONCLUSION

These results suggest that adequate nutrient intake is essential to maintain bone health in postmenopausal women.