BackgroundThe effect of vitamin D on colorectal adenomas may vary with regard to gender, localisation and histological type of the lesion. AimTo define the role of vitamin D and gender in a Caucasian cohort of subjects undergoing screening colonoscopy after consideration of established risk factors. MethodsOne thousand five hundred and thirty-two subjects (813 males, 58.89.7years; 719 females, 59.710.7years) were allocated to tertiles of 25-hydroxyvitamin D-3 [25(OH)D-3] serum concentrations. The number, localisation, size and histology of the detected colonic lesions were recorded. ResultsAmong men, no association was found between vitamin D and the total number, size and histological stage of adenomas at any site. In female subjects, less women with adenomas were found in the highest vitamin D tertile (N=42/239; 17.2%) as compared to the low vitamin D group (N=60/240; 25.0%; P=0.035). In particular, the number of women with adenomas in the proximal colon was significantly lower in the highest tertile (N=21/239, 8.8%) compared to the low vitamin D group (N=41/240; 17.1%; P=0.007). The rates at other sites were not different. The inverse association of vitamin D serum concentrations with the presence of adenomas in the proximal colon was maintained after adjustment for potential confounders. In 80 women on vitamin D supplementation, the rate of adenomas was lower compared to those not on supplementation (3/80; 3.8%; vs. 90/719; 12.5%; P=0.016). ConclusionsA potential preventive effect of vitamin D on colorectal adenomas was found in the proximal colon in women. This observation is supported by further decrease of lesions in the proximal colon of women on vitamin D supplementation.

Background Iron overload may contribute to the pathogenesis of insulin resistance. We aimed to investigate the relationship among iron stores, liver transaminases and components of the metabolic syndrome in healthy teenagers in a cross-sectional study. Material and methods We determined body mass index (BMI), waist-to-hip-ratio (WHR), blood pressure, liver ultrasound, serum lipids, insulin, fasting glucose, liver transaminase levels, hsCRP, iron parameters in 325 of 341 (95.3%) students (234 men, 16.7 +/- 1.7 years; 91 women, 16.5 +/- 1.7 years) of one single high school. Male and female study participants were allocated to increasing quartiles of body iron stores as assessed by sTfr/ferritin and alanine aminotranspeptidase (ALT) levels, and the distribution of cardiometabolic risk factors along quartiles was analysed. Regression analysis was performed to confirm the independent relationship between parameters. Results In male students, BMI, WHR, systolic and diastolic blood pressure, serum triglyceride levels and hsCRP were higher in the top sTfR/ferritin and ALT quartiles compared with the lowest quartiles (P < 0.01 for all parameters). In female students, sTfR/ferritin were not associated with antropomorphic cardiometabolic risk factors but with insulin resistance (HOMA-IR, P = 0.046). Moreover, ALT levels were independently related to BMI, waist and hip circumference, systolic blood pressure, serum triglyceride and insulin concentrations (P < 0.05 for all parameters) in female students. Conclusion These results provide evidence for linkage among body iron stores, transaminase activity and the prevalence of cardiometabolic risk factors in apparently healthy, non-obese adolescents even within the range of normal laboratory and anthropomorphic values and suggest that iron stores should be investigated as a potentially modifiable risk factor in healthy teenagers.

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Stadlmayr A, Aigner E, Steger B, Scharinger L, Lederer D, Mayr A, Strasser M, Brunner E, Heuberger A, Hohla F, Steinwendner J, Patsch W, Datz C (Oberndorf Hospital, Oberndorf; Paracelsus Medical University, Salzburg, Austria). Nonalcoholic fatty liver disease: an independent risk factor for colorectal neoplasia. J Intern Med 2011; 270: 41-49. Background and aims. Nonalcoholic fatty liver disease (NAFLD) is the hepatic manifestation of insulin resistance (IR), and IR is associated with an increased risk of colorectal carcinoma (CRC). Increased echogenicity suggesting NAFLD is a frequent incidental finding on ultrasound examination. We aimed to systematically evaluate whether NAFLD is an independent risk factor for colonic neoplasia. Patients and methods. One thousand two hundred and eleven patients (603 males, 60.6 +/- 9.6 years; 608 females, 61.1 +/- 10.3 years) who underwent screening colonoscopy according to national screening recommendations for CRC weree valuated in a cross-sectional study. Colorectal adenomas were classified as tubular adenoma, advanced adenoma(villous features, size 1 cm or high-grade dysplasia) or carcinoma. NAFLD was diagnosed by increased echogenicity on ultrasound examination after serological exclusion of infectious, immunological, hereditary or alcoholic aetiology. Results. Nonalcoholic fatty liver disease was diagnosed in 367 (60.8%) males and in 265 (43.5%) females. The total rate of adenomas was increased in subjects with NAFLD (243/367 vs. 107/236 in males, P = 0.010; 94/265 vs. 78/343 in females; P = 0.014). In particular, more tubular adenomas (127/367 vs. 56/236; P = 0.006), adenomas of the rectum (40/367 vs. 8/236; P = 0.004) and more cancers (6/367 vs. 1/236; P < 0.001) were observed in males with NAFLD. In females with NAFLD, more tubular adenomas (59/265 vs. 48/343; P = 0.011) and adenomas of the proximal colon (51/265 vs. 40/343; P = 0.041) were observed. Multivariate regression analyses demonstrated an independent association of colorectal adenomas with hepatic steatosis after adjustment for age, sex, body mass index and glucose intolerance (OR 1.47; 95% CI 1.079-2.003; P = 0.015). Conclusion. Patients with NAFLD undergoing screening colonoscopy reveal significantly more CRC precursor lesions and early CRC compared with subjects without NAFLD. This elevated risk is independent from other manifestations of IR. These findings suggest that detecting fatty liver on ultrasound should heighten the awareness for referral to screening colonoscopy.

In this paper, a multiscale material model for the prediction of viscous properties of bituminous mixtures is presented. The multiscale model is based on the mix design, i.e., volume fractions of different material phases and the intrinsic viscoelastic material behavior of the latter, making goal-oriented optimization of bituminous mixtures feasible. Previous developments for upscaling of viscoelastic properties of a bitumen/filler-composite (mastic) [Lackner, et al. J Mater Civil Eng 2005; 17(5): 485-91] and of asphalt [Aigner, et al. J Mater Civil Eng 2009; 21: 771-80] are improved with regards to (i) the employed mode of upscaling, i.e., the way information is transferred from one scale of observation to the next higher scale of observation, and (ii) the underlying micromechanical concept. As regards the latter, the use of the so-called generalized self-consistent scheme, suitable for highly-filled matrix/inclusion-type morphologies, as is the case for asphalt, is proposed. The assessment of the proposed upscaling scheme with respective experimental results indicates the improved suitability of the generalized self-consistent scheme versus the commonly employed (at least for modeling of matrix-inclusion materials) Mori-Tanaka scheme, resulting in a sound representation of test data. (C) 2011 Elsevier Ltd. All rights reserved.

Introduction. - As a small proportion of obese individuals do not develop metabolic complications and non-alcoholic fatty liver disease (NAFLD), this study aimed to provide a comprehensive clinical, metabolic and genetic description of obese subjects with healthy livers. Methods. - A total of 183 subjects were stratified, according to BMI, presence of metabolic syndrome, biochemical liver tests and hepatic steatosis on ultrasound, into: (i) lean controls (n =3D 69); (ii) obese healthy (n =3D 50); and (iii)obese NAFLD (n =3D 62) groups. Detailed clinical, genetic and metabolic evaluations were then performed. Results. - Obese healthy subjects did not differ in glucose parameters from lean controls, and had a lower rate of minor TM6SF2 gene variants compared with obese NAFLD (2/49 vs. 11/60, respectively; P =3D 0.035) and lean controls (13/64; P =3D 0.035), but significantly higher leptin concentrations than lean controls (P < 0.001); they also higher adiponectin concentrations (P < 0.001), and lower TNF-alpha and IL-6 concentrations (P =3D 0.01 and P < 0.001, respectively), than obese NAFLD subjects. Also, metabolomic studies identified ether- and ester-containing phospholipids [PC ae C44:6, PC ae C42:5, PC as C40:4; P < 0.001, corrected by the false discovery rate (FDR) method] and found that the amino-acids lysine, glycine and isoleucine (FDR < 0.001) differed between the two obese groups, but not between lean controls and obese healthy subjects. Conclusion. - Obese people with healthy livers are characterized by intact glucose homoeostasis, lower pro-inflammatory cytokine levels, and higher adiponectin and leptin concentrations compared with obese people with NAFLD. In addition, the major allele of TM6SF2, a set of phosphatidylcholines and several amino acids are associated with healthy livers in obesity. (C) 2018 Elsevier Masson SAS. All rights reserved.