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Sleep in shift work has been studied extensively in regular shift systems but to a lesser degree in irregular shifts. Our main aim was to examine the sleep-wake rhythm in shift combinations ending with the night or the morning shift in two irregular shift systems. Three weeks' sleep/work shift diary data, collected from 126 randomly selected train drivers and 104 traffic controllers, were used in statistical analyses including a linear mixed model and a generalized linear model for repeated measurements. The results showed that the sleep-wake rhythm was significantly affected by the shift combinations. The main sleep period before the first night shift shortened by about 2 h when the morning shift immediately preceded the night shift as compared with the combination containing at least 36 h of free time before the night shift (reference combination). The main sleep period before the night shift was most curtailed between two night shifts, on average by 2.9 and 3.5 h among the drivers and the controllers, respectively, as compared with the reference combination. Afternoon napping increased when the morning or the day shift immediately preceded the night shift, the odds being 4.35-4.84 in comparison with the reference combination. The main sleep period before the morning shift became 0.5 h shorter when the evening shift preceded the morning shift in comparison with the sleep period after a free day. The risk for dozing off during the shift was associated only with the shift length, increasing by 17 and 35% for each working hour in the morning and the night shift, respectively. The results demonstrate advantageous and disadvantageous shift combinations in relation to sleep and make it possible to improve the ergonomy of irregular shift systems.  相似文献   
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BackgroundIntestinal adaptation has been extensively studied experimentally, but very limited data is available on human subjects. In this study we assessed intestinal adaption in humans with short bowel syndrome (SBS).MethodsWe comparatively evaluated mucosal hyperplasia, inflammation, barrier function and nutrient transport using histology, immunohistochemistry and qPCR for selected 52 key genes in duodenal biopsies obtained from children with SBS after weaning off parenteral nutrition (n = 33), and matched controls without intestinal pathology (n = 12). Small bowel dilatation was assessed from contrast small bowel series.ResultsDuodenal mucosa of SBS children showed increased histologic inflammation of lamina propria (p = 0.033) and mucosal mRNA expression of tumor necrosis factor (p = 0.027), transforming growth factor (TGF)-β2 (p = 0.006) and caveolin-1 (CAV1; p = 0.001). Villus height, crypt depth, enterocyte proliferation, apoptosis and expression of proliferation and nutrient transport genes remained unchanged. Pathologic small bowel dilatation reduced crypt depth (p = 0.045) and downregulated mRNA expression of interleukin (IL)-6 by three-fold (p = 0.008), while correlating negatively with IL6 (r = -0.609, p = 0.004). Loss of ileocecal valve (ICV) upregulated mRNA expression of toll-like receptor 4 (TLR4), TGF-β1, CAV1, several apoptosis regulating genes, and mRNA expression of zonulin (p < 0.05 for all).ConclusionsDespite successful adaptation to enteral autonomy, duodenal mucosa of SBS children displayed histologic and molecular signs of abnormal inflammation and regulation of epithelial permeability, whereas no structural or molecular signs of adaptive hyperplasia or enhanced nutrient transport were observed. Excessive dilatation of the remaining small bowel paralleled impaired duodenal crypt homeostasis, while absence of ICV modified regulation of mucosal inflammation, regeneration and permeability.Level of evidenceII  相似文献   
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BackgroundWhen transcranial magnetic stimulation (TMS) is delivered close to the lateral aspects of the head, large-amplitude (~10–1000 μV) biphasic electroencephalographic (EEG) deflections, peaking at around 4–10 and 8–20 ms, appear.ObjectiveTo characterize the spatiotemporal features of these artifacts, to quantify the effect of stimulus parameters on them, and thus, to study the feasibility of different measurement procedures to decrease the artifacts online. Furthermore, to show that these deflections, when measured with a sample-and-hold system, mainly result from excitation of cranial muscles.MethodsThree subjects received TMS to 16 sites over the left hemisphere. TMS-compatible EEG was recorded simultaneously. Four other subjects received TMS to M1 with different coil rotation and tilt angles and stimulation intensities. We also stimulated a conductive phantom and recorded simultaneous EEG to exclude the possibility of residual electromagnetic artifacts.ResultsThe artifacts were largest when the stimulator was placed above cranial muscles, whereas stimulation of relatively central sites far from the muscles produced muscle artifact-free data. The laterally situated EEG channels were most severely contaminated. The artifacts were significantly reduced when reducing the intensity or when tilting or rotating the coil so that coil wings moved further away from the temporal muscle, while brain responses remained visible. Stimulation of the phantom did not produce such large-amplitude biphasic artifacts.ConclusionAltering the stimulation parameters can reduce the described artifact, while brain responses can still be recorded. The early, laterally appearing, large biphasic TMS-evoked EEG deflections recorded with a sample-and-hold system are caused by cranial muscle activation.  相似文献   
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Improvements in community health workers'' (CHWs) knowledge and practices in low‐income countries increasingly involve mobile phones and videos. However, little data exists on CHWs’ and mothers’ experiences of using such phones and videos. In this study, educational videos on nutrition, health and hygiene were downloaded onto mobile phones, which were given to 12 CHWs in rural Uganda. In 2018, these CHWs used the videos for a period of 3 months to support their work during their visits with families. We subsequently conducted individual interviews with eight CHWs and held four focus group discussions with 16 mothers. From the inductively analysed data, we identified four key themes: impact, competence, meaningfulness and choice, which are also dimensions of the Intrinsic Task Motivation Model. The model describes the motivation of workers and has previously been used in connection with CHWs. In our study, CHWs and mothers considered that the videos had more strongly impacted their learning than traditional teaching methods, and they felt the videos improved the child feeding and caring competence of both CHWs and mothers. Furthermore, the CHWs found that the videos enhanced the meaningfulness of their work, as they felt more greatly appreciated and necessary. In addition, they experienced more freedom of choice in their ability to influence their working routines. This study shows that educational videos are well received among CHWs and mothers. Educational videos are a promising method to maintain and improve the motivation of voluntary CHWs and influence correct child feeding and hygiene practices in Uganda.  相似文献   
6.
OBJECTIVE: Both epidemiological and experimental evidence suggests a protective effect of dietary fiber against disease, such as cancer and cardiovascular disease. The effects of fiber on lipoproteins are modest, indicating that other mechanisms may be involved. As the hemostatic effects of different types of fiber are poorly known, we compared the effects of wholemeal rye bread and low-fiber wheat bread on factors related to coagulation, fibrinolysis and platelet function. DESIGN: Subjects consumed rye and wheat bread as part of their habitual diet in a cross-over manner for 4 weeks, with a 4 week washout period between the diet periods. SUBJECTS: Forty healthy subjects (18 men, 22 women), aged 43+/-2 y. RESULTS: Mean daily intake of fiber during the rye bread period was 31 g for men and 26 g for women, while the respective figures for the wheat bread period were 15 g and 12 g. However, no significant differences between the two periods were seen in factor VII coagulant activity (FVIIc), fibrinogen, prothrombin fragments 1+2 (F1+2), tissue plasminogen activator (tPA) plasminogen activator inhibitor 1 (PAI-1) or 2,3,-dinor-thromboxane B2. Fibrin degradation products, D-dimers, were slightly lower after the wheat period (P=0.046). CONCLUSIONS: The results indicate that wheat and rye bread do not differ in their effects on coagulation, fibrinolysis or platelet function. Sponsorship: Fazer Bakeries Ltd, Lahti Finland; Vaasan & Vaasan Ltd, Helsinki, Finland.  相似文献   
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Epidemiological studies suggest that high consumption of red meat and saturated fat and low consumption of fiber are associated with an increased risk of colon cancer. Therefore, we studied whether diets high in red meat or high in different grain fibers as well as inulin, polydisperse beta(2-->1) fructan, could affect the formation of intestinal polyps in Apc(Min) mice. Min mice were fed the following high-fat (40% of energy) diets for 5-6 weeks; a high-beef diet and a casein-based diet without added fiber or casein-based diet with 10% (w/w) oat, rye or wheat bran, or 2.5% (w/w) inulin. One group had a normal low-fat AIN93-G diet. The mice fed the rye-bran diet had the lowest number of polyps in the distal small intestine [15.4 +/- 8.7 (mean +/- SD)], and in the entire intestine (26.4 +/- 12.1). The rye-bran group differed significantly (P = 0. 001-0.004) from the beef group (36.6 +/- 9.4 and 52.8 +/- 13.2). In addition, the beef group differed significantly from the AIN93-G group (P = 0.009) and also from the wheat-bran group (21.0 +/- 6.1 and 35.0 +/- 8.2; P = 0.02) in the distal small intestine. The inulin group (32.9 +/- 14.3 and 49.3 +/- 16.3), on the other hand, was close to the beef group and it differed significantly from the rye-bran group in the distal small intestine. The number of animals bearing tumors in the colon + caecum was only 33% in the rye-bran group when compared with 89% in the beef and 100% in the inulin groups. The mice fed the rye-bran and beef diets had the lowest levels of cytosolic beta-catenin (0.60 +/- 0.42 and 0.67 +/- 0.26) and they differed significantly (P = 0.040 and 0.062) from the mice fed the oat-bran diet (1.46 +/- 0.43). No differences between groups in expression of protein kinase C (PKC) alpha, betaII, delta and zeta were found. The four PKC isozymes were positively correlated with cytosolic beta-catenin levels (r = 0.62-0.68; P < 0.0001).  相似文献   
9.
Summary.Background: High intake of vegetables and fruits is associated with decreased risk of coronary heart disease. Part of these cardioprotective effects may be mediated via the antithrombotic effects of compounds found in vegetables and fruits, such as flavonoids.Aim of the study: To study the effects of high and low intake of vegetables, berries and apple on platelet function and inflammatory markers.Methods: The study was a randomised, controlled parallel human dietary intervention with healthy female and male volunteers (n = 77, 19–52 y). Nineteen healthy volunteers served as controls. The volunteers consumed one of four strictly controlled isocaloric 6-week diets containing either 810 or 196 g/10 MJ of vegetables, berries and apple and rich either in linoleic acid (11% of energy, en%) or oleic acid (12 en%). Blood and three 24-hour urine samples were collected at the beginning and at the end of the study period for analyses of various markers of platelet function and inflammation.Results: No differences between the treatment groups were seen in platelet count or volume, markers of platelet activation (ex vivo aggregation to ADP and thrombin receptor activating peptide, protein kinase C activity, urinary 2,3-dinor-thromboxane B2 excretion, plasma P-selectin), plasma intercellular adhesion molecule-1, sensitive C-reactive protein, or antiphospholipid antibodies.Conclusions: The results indicate that in healthy volunteers 6-week diets differing markedly in the amounts of vegetables, berries and apple do not differ in their effects on platelets or inflammation.  相似文献   
10.
BACKGROUND: Low back disorders are among the most common health problems in industrialized societies. We examined the relationship between occupational exposures and severe lumbar intervertebral disc disorders (LIDD). METHODS: Information on inpatient care for LIDD (ICD-10: M51.1-51.9) in Finnish hospitals during 1996 was linked with the 1995 Population Census, and based on occupational title with the Finnish Job Exposure Matrix and the Occupational Lifestyle Matrix. There were 3,863 individuals hospitalized due to LIDD among occupationally active Finns. Poisson regression analyses were made with the total occupationally active population as reference. RESULTS: In a multivariate analysis in women, accident risk, job control, and three-shift work were associated with hospitalization, together with age, education, personal income, and average body mass index (BMI) by occupation. In men, accident risk and job control were associated with hospital admissions, allowing for age, education, and income. CONCLUSIONS: Accident risk and job control increased the risk of hospitalization for LIDD in both sexes. Three-shift work and BMI were also predictive of hospital admission among women.  相似文献   
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