Reproducibility and validity of the stair-climb test for fire fighters

Purpose  

A new job-specific test for fire fighters, the stair-climb test (FFstair-climb) was evaluated for reproducibility and validity for use in future workers’ health surveillance.     

Plant from New-Caledonia. Alkaloids of Melodinus reticulatus

(-)Tabersonine and (-)-11-methoxytabersonine were isolated from fruits of Melodinus reticulatus. Stems and leaves contain uvaol and eight alkaloids, five of which were previously described: (-)tabersonine, venalstonidine, kopsinine, venalstonine and its 3-oxoderivative. Three are new: 19-hydroxyvenalstonine, 19-hydroxyvenalstonidine and 3-oxovenalstonidine.     

Age-related changes in slow wave sleep and REM sleep and relationship with growth hormone and cortisol levels in healthy men

CONTEXT: In young adults, sleep affects the regulation of growth hormone (GH) and cortisol. The relationship between decreased sleep quality in older adults and age-related changes in the regulation of GH and cortisol is unknown. OBJECTIVE: To determine the chronology of age-related changes in sleep duration and quality (sleep stages) in healthy men and whether concomitant alterations occur in GH and cortisol levels. DESIGN AND SETTING: Data combined from a series of studies conducted between 1985 and 1999 at 4 laboratories. SUBJECTS: A total of 149 healthy men, aged 16 to 83 years, with a mean (SD) body mass index of 24.1 (2.3) kg/m( 2), without sleep complaints or histories of endocrine, psychiatric, or sleep disorders. MAIN OUTCOME MEASURES: Twenty-four-hour profiles of plasma GH and cortisol levels and polygraphic sleep recordings. RESULTS: The mean (SEM) percentage of deep slow wave sleep decreased from 18.9% (1.3%) during early adulthood (age 16-25 years) to 3.4% (1.0%) during midlife (age 36-50 years) and was replaced by lighter sleep (stages 1 and 2) without significant increases in sleep fragmentation or decreases in rapid eye movement (REM) sleep. The transition from midlife to late life (age 71-83 years) involved no further significant decrease in slow wave sleep but an increase in time awake of 28 minutes per decade at the expense of decreases in both light non-REM sleep (-24 minutes per decade; P<.001) and REM sleep (-10 minutes per decade; P<.001). The decline in slow wave sleep from early adulthood to midlife was paralleled by a major decline in GH secretion (-372 microg per decade; P<.001). From midlife to late life, GH secretion further declined at a slower rate (-43 microg per decade; P<.02). Independently of age, the amount of GH secretion was significantly associated with slow wave sleep (P<.001). Increasing age was associated with an elevation of evening cortisol levels (+19. 3 nmol/L per decade; P<.001) that became significant only after age 50 years, when sleep became more fragmented and REM sleep declined. A trend for an association between lower amounts of REM sleep and higher evening cortisol concentrations independent of age was detected (P<.10). CONCLUSIONS: In men, age-related changes in slow wave sleep and REM sleep occur with markedly different chronologies and are each associated with specific hormonal alterations. Future studies should evaluate whether strategies to enhance sleep quality may have beneficial hormonal effects. JAMA. 2000;284:861-868     

Congenital hypofibrinogenemia: characterization of two missense mutations affecting fibrinogen assembly and secretion

Congenital hypofibrinogenemia is a rare bleeding disorder characterized by abnormally low levels of fibrinogen in plasma, generally due to heterozygous mutations in one of the three fibrinogen genes (FGA, FGB, and FGG, coding for Aα, Bβ, and γ chain, respectively). Hypofibrinogenemic patients are usually asymptomatic, whereas individuals bearing similar mutations in the homozygous or compound heterozygous state develop a severe bleeding disorder: afibrinogenemia. The mutational spectrum of these quantitative fibrinogen disorders includes large deletions, point mutations causing premature termination codons, and missense mutations affecting fibrinogen assembly or secretion, distributed throughout the 50-kb fibrinogen gene cluster. In this study, we report the mutational screening of two unrelated hypofibrinogenemic patients leading to the identification of two missense mutations, one hitherto unknown (αCys45Phe), and one previously described (γAsn345Ser). The involvement of αCys45Phe and γAsn345Ser in the pathogenesis of hypofibrinogenemia was investigated by in-vitro expression experiments. Both mutations were demonstrated to cause a severe impairment of intracellular fibrinogen processing, either by affecting half-molecule dimerization (αCys45Phe) or by hampering hexamer secretion (γAsn345Ser).     

Regional differences in cardiovascular risk factor profile cannot fully explain differences in cardiovascular morbidity in the Netherlands: a comparison of two urban areas

BACKGROUND: Our objective was to investigate whether a region in the south of the Netherlands (Heerlen/Kerkrade) had a high burden of cardiovascular disease in comparison with a nearby region (Maastricht) and the average Dutch population, respectively. We also wanted to determine if there are interregional differences in cardiovascular risk factor profile. DESIGN: Cross-sectional study. METHODS: Data from a nationwide registry (CBS) were used to analyse cardiovascular mortality in the two regions and the average in the Netherlands. Data from a primary care morbidity registration network (RNH) were used to compare cardiovascular morbidity and cardiovascular risk factors in both regions. A standardisation procedure was carried out for age and sex. Data were analysed using logistic regression analyses. RESULTS: The overall cardiovascular mortality rate was higher in the Heerlen/Kerkrade region (7.8 per thousand) compared with Maastricht (6.1 per thousand, OR=1.3, 95% CI 1.2-1.5) and the average in the Netherlands (5.7 per thousand). Similarly, most cardiovascular morbidity rates for Heerlen/Kerkrade were more elevated compared with the RNH overall and with Maastricht. Prevalence rates of risk factors such as diabetes mellitus (7.2%, OR=1.5, 95% CI 1.3-1.7) and overweight (10.8%, OR= 2.0, 95% CI 1.8-2.2) were significantly higher in the Heerlen/Kerkrade region compared with Maastricht. There were no differences with regard to hypertension (15.2%, OR=1.0, 95% CI 0.9-1.1). CONCLUSION: Heerlen/Kerkrade is indeed a region with a high burden of cardiovascular disease. Differences in morbidity between Heerlen/Kerkrade and Maastricht cannot be fully explained by differences in cardiovascular risk factor profile.     

Effects of Dietary Plant Sterols and Stanol Esters with Low- and High-Fat Diets in Chronic and Acute Models for Experimental Colitis

In this study, we evaluated the effects of dietary plant sterols and stanols as their fatty acid esters on the development of experimental colitis. The effects were studied both in high- and low-fat diet conditions in two models, one acute and another chronic model of experimental colitis that resembles gene expression in human inflammatory bowel disease (IBD). In the first experiments in the high fat diet (HFD), we did not observe a beneficial effect of the addition of plant sterols and stanols on the development of acute dextran sulphate sodium (DSS) colitis. In the chronic CD4CD45RB T cell transfer colitis model, we mainly observed an effect of the presence of high fat on the development of colitis. In this HFD condition, the presence of plant sterol or stanol did not result in any additional effect. In the second experiments with low fat, we could clearly observe a beneficial effect of the addition of plant sterols on colitis parameters in the T cell transfer model, but not in the DSS model. This positive effect was related to the gender of the mice and on Treg presence in the colon. This suggests that especially dietary plant sterol esters may improve intestinal inflammation in a T cell dependent manner.