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R. Urgert S. Meyboom M. Kuilman H. Rexwinkel M. N. Vissers M. Klerk M. B. Katan 《BMJ (Clinical research ed.)》1996,313(7069):1362-1366
OBJECTIVE: To study the effects of prolonged intake of cafetière coffee, which is rich in the diterpenes cafestol and kahweol, on serum aminotransferase and lipid concentrations. DESIGN: Randomised parallel controlled trial. SUBJECTS: 46 healthy men and women aged 19 to 69. INTERVENTION: Consumption of five to six strong cups (0.9 litres) a day of either cafetière (22 subjects) or filtered coffee (24 subjects) for 24 weeks. MAIN OUTCOME MEASURES: Mean changes in serum aminotransferase and lipid concentrations. RESULTS: Cafetière coffee raised alanine aminotransferase concentration by up to 80% above baseline values relative to filtered coffee. After 24 weeks the rise was still 45% (9 U/l (95% confidence interval 3 to 15 U/l), P = 0.007). Alanine aminotransferase concentration exceeded the upper limit of normal in eight of the 22 subjects drinking cafetière coffee, being twice the upper limit of normal in three of them. Cafetière coffee raised low density lipoprotein cholesterol concentrations by 9-14%. After 24 weeks the rise was 0.26 mmol/l (0.04 to 0.47 mmol/l) (P = 0.03) relative to filtered coffee. Triglyceride concentrations initially rose by 26% with cafetière coffee but returned close to baseline values within six months. All increases were reversible after the intervention was stopped. CONCLUSIONS: Daily consumption of five to six cups of strong cafetière coffee affects the integrity of liver cells as suggested by small increases in serum alanine aminotransferase concentration. The effect does not subside with prolonged intake. High intakes of coffee brews rich in cafestol and kahweol may thus be responsible for unexplained increases in this enzyme activity in apparently healthy subjects. Cafetière coffee also raises low density lipoprotein cholesterol concentration and thus the risk of coronary heart disease. 相似文献
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Background
Alcoholism presents widespread social and human health problems. Alcohol sensitivity, the development of tolerance to alcohol and susceptibility to addiction vary in the population. Genetic factors that predispose to alcoholism remain largely unknown due to extensive genetic and environmental variation in human populations. Drosophila, however, allows studies on genetically identical individuals in controlled environments. Although addiction to alcohol has not been demonstrated in Drosophila, flies show responses to alcohol exposure that resemble human intoxication, including hyperactivity, loss of postural control, sedation, and exposure-dependent development of tolerance. 相似文献14.
Most bacteria in the ocean can be motile. Chemotaxis allows bacteria to detect nutrient gradients, and hence motility is believed to serve as a method of approaching sources of food. This picture is well established in a stagnant environment. In the ocean a shear microenvironment is associated with turbulence. This shear flow prevents clustering of bacteria around local nutrient sources if they swim in the commonly assumed "run-and-tumble" strategy. Recent observations, however, indicate a "back-and-forth" swimming behavior for marine bacteria. In a theoretical study we compare the two bacterial swimming strategies in a realistic ocean environment. The "back-and-forth" strategy is found to enable the bacteria to stay close to a nutrient source even under high shear. Furthermore, rotational diffusion driven by thermal noise can significantly enhance the efficiency of this strategy. The superiority of the "back-and-forth" strategy suggests that bacterial motility has a control function rather than an approach function under turbulent conditions. 相似文献
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Microorganisms are associated with a variety of ancient geological materials. However, conclusive proof that these organisms
are as old as the geological material and not more recent introductions has generally been lacking. Over the years, numerous
reports of the isolation of ancient bacteria from geological materials have appeared. Most of these have suffered from the
fact that the protocol for the surface sterilization of the sample was either poorly defined, inadequate or rarely included
data to validate the overall effectiveness of the sterilization protocol. With proper sterility validation and isolation protocol,
a legitimate claim for the isolation of an ancient microbe can be made. Biochemical, physiological, or morphological data
indicate that these ancient microbes are not significantly different from modern isolates. As the role (decomposition) of
modern and ancient microbes has not changed over time, it is probably unreasonable to expect these organisms to be vastly
different. A discussion on the reasons for the homogeneity of ancient and modern microbes is presented. Journal of Industrial Microbiology & Biotechnology (2002) 28, 32–41 DOI: 10.1038/sj/jim/7000174
Received 20 May 2001/ Accepted in revised form 16 June 2001 相似文献
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Architecture of epigenetic reprogramming following Twist1-mediated epithelial-mesenchymal transition
Gabriel G Malouf Joseph H Taube Yue Lu Tapasree Roysarkar Shoghag Panjarian Marcos RH Estecio Jaroslav Jelinek Jumpei Yamazaki Noel J-M Raynal Hai Long Tomomitsu Tahara Agata Tinnirello Priyanka Ramachandran Xiu-Ying Zhang Shoudan Liang Sendurai A Mani Jean-Pierre J Issa 《Genome biology》2013,14(12):R144
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Y Deng J Zhao D Sakurai KM Kaufman JC Edberg RP Kimberly DL Kamen GS Gilkeson CO Jacob RH Scofield CD Langefeld JA Kelly ME Alarcón-Riquelme BIOLUPUS GENLES Networks JB Harley TJ Vyse BI Freedman PM Gaffney KM Sivils JA James TB Niewold RM Cantor W Chen BH Hahn EE Brown PROFILE BP Tsao 《Arthritis research & therapy》2012,14(Z3):A5
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Alcoholism is a significant public health problem. A picture of the genetic architecture underlying alcohol-related phenotypes
is emerging from genome-wide association studies and work on genetically tractable model organisms. 相似文献
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