Low-FODMAP vs regular rye bread in irritable bowel syndrome:Randomized SmartPill~ study

AIM To compare the effects of regular vs low-FODMAP rye bread on irritable bowel syndrome(IBS) symptoms and to study gastrointestinal conditions with Smart Pill?.METHODS Our aim was to evaluate if rye bread low in FODMAPs would cause reduced hydrogen excretion,lower intraluminal pressure,higher colonic p H,different transit times,and fewer IBS symptoms than regular rye bread.The study was a randomized,double-blind,controlled cross-over meal study.Female IBS patients(n = 7) ate study breads at three consecutive meals during one day.The diet was similar for both study periods except for the FODMAP content of the bread consumed during the study day.Intraluminal p H,transit time,and pressure were measured by Smart Pill,an indigestible motility capsule.RESULTS Hydrogen excretion(a marker of colonic fermentation) expressed as area under the curve(AUC)(0-630 min) was [median(range)] 6300(1785-10800) ppm?min for low-FODMAP rye bread and 10 635(4215-13080) ppm?min for regular bread(P = 0.028).Mean scores of gastrointestinal symptoms showed no statistically significant differences but suggested less flatulence after low-FODMAP bread consumption(P = 0.063).Intraluminal pressure correlated significantly with total symptom score after regular rye bread(ρ = 0.786,P = 0.036) and nearly significantly after lowFODMAP bread consumption(ρ = 0.75,P = 0.052).We found no differences in p H,pressure,or transit times between the breads.Gastric residence of Smart Pill was slower than expected.Smart Pill left the stomach in less than 5 h only during one measurement(out of 14 measurements in total) and therefore did not follow on par with the rye bread bolus.CONCLUSION Low-FODMAP rye bread reduced colonic fermentation vs regular rye bread.No difference was found in median values of intraluminal conditions of the gastrointestinal tract.     

Alcohol consumption and the risk of stroke among hypertensive and overweight men

High blood pressure and overweight are risk factors for stroke. The aim of the present study was to examine the association between alcohol consumption and the risk of stroke according to the level of blood pressure and body weight. This study is a population-based sample of men with an average follow-up of 14.9 years from eastern Finland. A total of 2,599 men with no history of stroke at baseline participated. During the follow-up period, 224 strokes occurred, of which 181 were ischemic strokes. After adjustment for age, year of examination, socioeconomic status, serum LDL cholesterol, body mass index, smoking and energy expenditure of physical activity (kcal/day), there was a significant trend of an increased risk for any and ischemic stroke among hypertensive men. Hypertensive (blood pressure of over 140/90 mm Hg) men, who did not consume alcohol had a 1.72-fold (95 % CI 1.12–2.66; p = 0.014) relative risk (RR) for any stroke and a 1.90-fold (95 % CI 1.15–3.13; p = 0.012) RR for ischemic stroke. Among hypertensive men who consumed alcohol RR was 1.86-fold (95 % CI 1.20–2.89; p = 0.005) for any stroke and 2.02-fold (95 % CI 1.21–3.35; p = 0.007) for ischemic stroke. Men who did not consume alcohol with elevated BMI (≥26.4 kg/m²) had a 1.63-fold RR (95 % CI 1.11–2.40; p = 0.013) for any stroke and a 1.33-fold RR (95 % CI 0.87–2.04; p = 0.199) for ischemic stroke after adjusting for risk factors. Overweight men (≥26.4 kg/m²) who consumed alcohol had a 1.73-fold RR (95 % CI 1.18–2.54; p = 0.005) for any stroke and a 1.71-fold RR (95 % CI 1.14–2.57; p = 0.010) for ischemic stroke after being adjusted for risk factors. In conclusion, this population-based prospective study shows that hypertensive and overweight men who consumed alcohol had an increased risk for stroke.     

Long Working Hours and Sleep Disturbances: The Whitehall II Prospective Cohort Study

Study Objective:

To examine whether exposure to long working hours predicts various forms of sleep disturbance; short sleep, difficulty falling asleep, frequent waking, early waking and waking without feeling refreshed.

Design:

Prospective study with 2 measurements of working hours (phase 3, 1991–1994 and phase 5, 1997–1999) and 2 measurements of subjective sleep disturbances (phase 5 and phase 7, 2002–2004).

Setting:

The Whitehall II study of British civil servants.

Participants:

Full time workers free of sleep disturbances at phase 5 and employed at phases 5 and 7 (n = 937–1594) or at phases 3, 5, and 7 (n = 886–1510).

Measurements and Results:

Working more than 55 hours a week, compared with working 35–40 hours a week, was related to incident sleep disturbances; demographics-adjusted odds ratio (95% CI) 1.98 (1.05, 3.76) for shortened sleeping hours, 3.68 (1.58, 8.58) for difficulty falling asleep; and 1.98 (1.04, 3.77) for waking without feeling refreshed. Repeat exposure to long working hours was associated with odds ratio 3.24 (1.45, 7.27) for shortened sleep, 6.66 (2.64, 16.83) for difficulty falling asleep, and 2.23 (1.16, 4.31) for early morning awakenings. Some associations were attenuated after adjustment for other risk factors. To a great extent, similar results were obtained using working hours as a continuous variable. Imputation of missing values supported the findings on shortened sleep and difficulty in falling asleep.

Conclusion:

Working long hours appears to be a risk factor for the development of shortened sleeping hours and difficulty falling asleep.

Citation:

Virtanen M; Ferrie JE; Vahtera J; Elovainio M; Singh-Manoux A; Marmot MG; Kivimäki M. Long working hours and sleep disturbances: the whitehall II prospective cohort study. SLEEP 2009;32(6):737–745.     

Diverse associations of 25‐hydroxyvitamin D and 1,25‐dihydroxy‐vitamin D with dyslipidaemias

Abstract. Karhapää P, Pihlajamäki J, Pörsti I, Kastarinen M, Mustonen J, Niemelä O, Kuusisto J (University of Eastern Finland, Kuopio; University of Tampere, Tampere; and Laboratory and Medical Research Unit, University of Tampere, Tampere; Finland). Diverse associations of 25‐hydroxyvitamin D and 1,25‐dihydroxyvitamin D with dyslipidaemias. J Intern Med 2010; 268 : 604–610. Background and Aim. Previous studies have suggested a link between circulating levels of 25‐hydroxyvitamin D (25‐D) and dyslipidaemias. However, it is not known whether 25‐D and the active hormone 1,25‐dihydroxyvitamin D (1,25‐D) have similar associations with dyslipidaemias. Therefore, we studied the associations between both 25‐D and 1,25‐D and total cholesterol (total‐C), low‐density lipoprotein cholesterol (LDL‐C), high‐density lipoprotein cholesterol (HDL‐C) and triglycerides in a population‐based study. Design. Cross‐sectional population‐based study. Setting. Kuopio, Eastern Finland. Subjects. A total of 909 men, aged from 45 to 70 years, who were not receiving antidiabetic medication were enrolled. Main Outcome Measures. Fasting serum samples were obtained for measurement of 25‐D, 1,25‐D and lipid levels. An oral glucose tolerance test was performed, and insulin sensitivity was evaluated using the Matsuda insulin sensitivity index (Matsuda ISI). Results. We found a significant inverse association between 25‐D and total‐C, LDL‐C and triglycerides (β = ?0.15, ?0.13 and ?0.17, respectively, P < 0.001), but no association between 25‐D and HDL‐C was observed. By contrast, 1,25‐D was associated with HDL‐C (β = 0.18, P < 0.001), whereas no relationship was found between 1,25‐D and LDL‐C or triglycerides. The associations remained significant after the exclusion of subjects receiving statin treatment and after adjustment for age, waist circumference, body mass index, alcohol consumption, smoking, renal function, glucose tolerance and Matsuda ISI. Conclusion. Low levels of active vitamin D (1,25‐D) are associated with low HDL‐C levels, whereas low levels of the storage form 25‐D are associated with high levels of total‐C, LDL‐C and triglycerides. Our findings may provide new insights into the understanding of the link between vitamin D deficiency and cardiovascular disease.     

Deconvolution-based partial volume correction in Raclopride-PET and Monte Carlo comparison to MR-based method

In this work, we evaluated three iterative deconvolution algorithms and compared their performance to partial volume (PV) correction based on structural imaging in brain positron emission tomography (PET) using a database of Monte Carlo-simulated images. We limited our interest to quantitative radioligand PET imaging, particularly to (11)C-Raclopride and striatal imaging. The studied deconvolution methods included Richardson-Lucy, reblurred Van Cittert, and reblurred Van Cittert with the total variation regularization. We studied the bias and variance of the regional estimates of binding potential (BP) values and the accuracy of regional TACs as a function of the applied image processing. The resolution/noise tradeoff in parametric BP images was addressed as well. The regional BP values and TACs obtained by deconvolution were almost as accurate than those by structural imaging-based PV correction (GTM method) when the ideal volumes of interests (VOIs) were used to extract TACs from the images. For deconvolution methods, the ideal VOIs were slightly eroded from the exact anatomical VOI to limit the bias due to tissue fraction effect which is not corrected for by deconvolution-based methods. For the GTM method, the ideal VOIs were the exact anatomical VOIs. The BP values and TACs by deconvolution were less affected by segmentation and registration errors than those with the GTM-based PV correction. The BP estimates and TACs with deconvolution-based PV correction were more accurate than BPs and TACs derived without PV correction. The parametric images obtained by the deconvolution-based PV correction showed considerably improved resolution with only slightly increased noise level compared to the case with no PV correction. The reblurred Van Cittert method was the best of the studied deconvolution methods. We conclude that the deconvolution is an interesting alternative to structural imaging-based PV correction as it leads to quantification results of similar accuracy, and it is less prone to registration and segmentation errors than structural imaging-based PV correction. Moreover, PV-corrected parametric images can be readily computed based on deconvolved dynamic images.     

Rapid Homogeneous Immunoassay Based on Time-Resolved F?rster Resonance Energy Transfer for Serodiagnosis of Acute Hantavirus Infection

We recently introduced a homogeneous immunoassay based on time-resolved Förster resonance energy transfer (TR-FRET) elicited by fluorophore-labeled antigen and fluorophore-labeled protein L, bound by an immunoglobulin. As the first clinical application, we employ this approach (LFRET) in serodiagnosis of Puumala hantavirus (PUUV) infection. A reference panel containing serum from individuals with acute (n = 21) or past (n = 17) PUUV infection and from PUUV-seronegative individuals (n = 20) was used to define the parameters. The clinical assay performance was evaluated with a prospectively collected serum panel (panel 2; n = 153). Based on the results for panel 1, the threshold for positivity was set at a signal level that was 3-fold over background, while those with a signal <3-fold over the background level were considered PUUV seronegative. With panel 1, 20/21 acute- and 7/10 past-infection samples induced positive signals, compared to 0/20 seronegatives. With panel 2, a positive signal was obtained in 39/40 acute- and 4/10 past-infection samples, as opposed to 7/103 seronegatives. However, after IgG depletion, 58/61 acute-infection samples were LFRET positive, while all past-infection and seronegative samples were negative, corresponding to 100% specificity and 95% sensitivity in detection of acute PUUV infection. We demonstrate that the novel immunoassay is a promising tool for rapid serodiagnosis of acute Puumala virus infection.