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11.
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Ultraviolet-light induced p53 mutational spectrum in yeast is indistinguishable from p53 mutations in human skin cancer 总被引:1,自引:2,他引:1
Inga A; Scott G; Monti P; Aprile A; Abbondandolo A; Burns PA; Fronza G 《Carcinogenesis》1998,19(5):741-746
Ultraviolet (UV) light has been associated with the development of human
non-melanoma skin cancers (NMSC). Such cancers often exhibit mutations in
the p53 tumour suppressor gene. In order to determine the UV-induced p53
mutation spectrum, a yeast expression vector that harbours a human
wild-type p53 cDNA was UV-irradiated in vitro and transfected into a yeast
strain that contained the ADE2 gene regulated by a p53-responsive promoter.
Forty-five mutant clones contained 51 mutations. Seven mutations were
tandem base pair substitutions, four of which being CC-->TT, hallmark
mutations of UV mutagenesis. Eighty percent (41/51) of the mutations were
single or non-tandem base pair substitutions, the majority of which (27/41)
were C-->T transitions. Ninety-five percent of such mutations occurred
at dipyrimidine sites. Through a rigorous statistical test, the UV-induced
p53 mutation spectrum appears to differ significantly (P < 0.008) from
the one induced by the antineoplastic drug
chloroethyl-cyclohexyl-nitrosourea, and to be indistinguishable from the
one observed in NMSC (P = 0.4). These results demonstrate that the assay
allows the determination of carcinogen-specific p53 mutation fingerprints
and represents a new tool for molecular epidemiology.
相似文献
13.
Knut-Inge Klepp Carmen Perez Rodrigo Inga Thorsdottir Pernille Due Maria Daniel Vaz de Almeida Ibrahim Elmadfa Alexandra Wolf Jóhanna Haraldsdóttir Johannes Brug Michael Sjöström Agneta Yngve Ilse De Bourdeaudhuij 《Zeitschrift fur Gesundheitswissenschaften》2005,13(2):97-101
Aim The Pro Children consortium consists of the following partners: Knut-Inge Klepp (Coordinator), Department of Nutrition, University of Oslo, Norway; Carmen Perez Rodrigo, Unidad de Nutricion Comunitaria, Bilbao, Spain; Inga Thorsdottir, Unit for Nutrition Research, Landspitali University Hospital, Reykjavik, Iceland; Pernille Due, Department of Social Medicine, University of Copenhagen, Denmark; Maria Daniel Vaz de Almeida, Faculdade de Ciências da Nutrição e Alimentação da Universidade do Porto, Portugal; Ibrahim Elmadfa and Alexandra Wolf, Institute of Nutrition, University of Vienna, Austria; Jóhanna Haraldsdóttir, Research Department of Human Nutrition, Royal Veterinary and Agricultural University, Copenhagen, Denmark; Johannes Brug, Erasmus Medical Center Rotterdam, Department of Public Health, The Netherlands; Michael Sjöström and Agneta Yngve, Unit for Preventive Nutrition, Karolinska Institutet, Stockholm, Sweden; Ilse De Bourdeaudhuij, Department of Movement and Sport Sciences, Ghent University, Belgium.The Pro Children study is designed to assess vegetable and fruit consumption and determinants of the consumption patterns among European school children and their parents. A second objective is to develop and test strategies for promoting increased consumption of vegetables and fruits among school children and their parents.Subjects and methods Surveys of national, representative samples of 11-year-old school children and their parents were conducted in nine countries during October–November 2003, i.e. in Austria, Belgium, Denmark, Iceland, The Netherlands, Norway, Portugal, Spain and Sweden. Comprehensive school-based educational programmes were developed and tested in three settings, i.e. in the Bilbao region, Spain, in Rotterdam, The Netherlands, and in Buskerud county of Norway. A 24-h recall format and frequency items assessing regular intake were used to assess vegetable and fruit consumption. Determinants were assessed employing the theoretical framework of the ASE model (Attitudes, Social Influences and Self-Efficacy), including cognitive factors, normative influences, skills and environmental barriers related to vegetable and fruit consumption. The intervention programmes were tested employing a group-randomized trial design where schools were randomly allocated to an intervention arm and a delayed intervention arm. Surveys among all participating children and their parents were conducted prior to the initiation of the intervention (September 2003; month 0), immediately after the end of the intervention (at month 8) and at the end of the subsequent school year (month 20).Results Preliminary data from the project indicate that girls eat vegetables and fruit significantly more often than do boys across all participating countries. There are no sex differences, however, with respect to perceived availability of vegetables and fruit at home and outside the home setting. In all countries, perceived availability appears to be significantly associated with reported frequency of both vegetable and fruit consumption.Conclusion Experience so far indicates that the Pro Children Project will succeed in producing valid and reliable research instruments for assessing vegetable and fruit consumption among school children and their parents and that comparable, comprehensive intervention programmes can be implemented across geographic and cultural settings within Europe. 相似文献
14.
Klaus Lieb Bernd L. Fiebich Inga Herpfer Michela Mantovani Marlene Lffler Thomas J. Feuerstein 《European neuropsychopharmacology》2005,15(6):641-646
Some studies have demonstrated antidepressant activity of neurokinin-1-receptor antagonists (NK-1-RA) in major depressive disorder. However, the underlying mechanisms of this antidepressant effect are largely unknown. Preclinical studies in rats and mice have suggested that NK-1-RA do increase the neuronal release of serotonin (5-HT). This, however, seems to be compensated by an increased 5-HT reuptake, indicating that NK-1-RA have no inhibitory effect on the 5-HT transporter in rodents. Given the possibility that modulation of neurotransmitter release and reuptake may differ between species, with major differences found between rodents and humans, we investigated for the first time the possible modulatory effect of NK-1-RA on 5-HT uptake in human brain synaptosomes and compared it with the situation in rat cortex. We found that the specific human NK-1-RA L-733060, in contrast to the SSRI fluvoxamine (IC50 = 10− 7.96 M) did not inhibit 5-HT uptake in human brain synaptosomes and did not modulate fluvoxamine-induced 5-HT uptake inhibition at 1 μM. Furthermore, substance P as well as Sar9Met(O2)11SP, as the major agonists at the NK-1-R, did not modulate 5-HT uptake in human brain synaptosomes. Similar results were found in rat cortex synaptosomes by using the rat-specific NK-1-RA WIN51708. These results show that in humans, as in rodents, inhibition of the 5-HT transporter is probably not the underlying mechanism of the assumed antidepressant activity of NK-1-RA. 相似文献
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Kristina Geyer Julia Günther Julia Hoffmann Monika Spies Roxana Raab Ana Zhelyazkova Inga Rose Hans Hauner 《Geburtshilfe und Frauenheilkunde》2022,82(7):736
Introduction The nutritional status of women before, during, and after pregnancy plays an important role in the health of mother and child. In addition to a balanced mixed diet, the increased need for folic acid and iodine should be met and ensured with supplements. The aim of this study was to assess dietary supplementation in the context of pregnancy and to investigate the effect of targeted counselling on supplementation behavior during and after pregnancy. Methods In the context of the “Gesund leben in der Schwangerschaft” (GeliS; “Healthy living in pregnancy”) trial, women in the intervention group (IG) received four structured lifestyle counselling sessions during pregnancy as well as postpartum, during which they were informed about appropriate dietary supplementation. The women in the control group (CG) received routine prenatal care. The intake of dietary supplements was recorded at different points using a questionnaire. Results In total, 2099 women were included in the analysis. Prior to conception, 31.3% of the women in the IG and 31.4% of the women in the CG took folic acid supplements. Prenatally, about half of the women took folic acid (IG: 54.1%; CG: 52.0%) and iodine (IG: 50.2%; CG: 48.2%). Statistically significant differences between the groups with regard to supplementation behavior could not be observed, neither prior to inclusion in the study nor during the intervention. During pregnancy, 23.0% of all women took docosahexaenoic acid (DHA) supplements and 21.8% iron supplements. 49.4% of the women additionally took vitamin D supplements. A higher educational level (p < 0.001), advanced age (p < 0.001), primiparity (p < 0.001), and a vegetarian diet (p = 0.037) were all associated with a higher level of dietary supplementation. Conclusion The GeliS lifestyle counselling did not significantly improve the supplementation behavior of women during and after pregnancy. Women should be informed about adequate dietary supplementation early on within the scope of gynecological prenatal care. Key words: dietary supplementation, folic acid, iodine, pregnancy, postpartum 相似文献
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Interest in plant-based nutrition has steadily increased in the western world in the recent years. The number of people following a meat-reduced, flexitarian diet is growing continuously. However, little is known about the diet quality of flexitarians compared to vegans or omnivores. Therefore, in this cross-sectional study, the food intake of 94 participants aged between 25–45 years was recorded via a validated food frequency questionnaire and 28 self-designed questions about the consumption of plant-based alternatives. An adapted Healthy Eating Index, HEI-flex, was developed to evaluate the diet quality of flexitarians, vegans and omnivores. Higher score points (SP) of the HEI-flex are associated with higher compliance with the official diet recommendations (Vmax = 100 SP). Finally, flexitarians scored significantly more highly when compared to omnivores (54 ± 8 vs. 47 ± 9 SP; p = 0.008) but lower than vegans (54 ± 8 vs. 61 ± 10 SP; p = 0.010). The results showed that the HEI-flex is a useful tool for assessing and comparing the diet quality of flexitarians, vegans and omnivores. Despite the consumption of highly processed plant-based alternatives, reduction in meat and meat products seems to be accompanied by increased overall diet quality. 相似文献
19.
Proteins BASP1 and MARCKS are abundant in axonal endings of neurons. Similarly to brain-specific protein GAP-43, BASP1 and MARCKS are reversibly bound to the plasma membrane. These proteins control both actin polymerization and actin cytoskeleton binding to the membrane. Performing these functions, BASP1 and MARCKS take part in growth cone guidance during development and in neurotransmitter secretion in adults. These activities predetermine the pivotal role of BASP1 and MARCKS in learning and memory. BASP1 and MARCKS were also found in non-nerve tissues, in particular, in the kidney and testis. Evidently, the physiological roles of these proteins differ in different tissues. Correspondingly, their intracellular location and activities may not be similar to those in neurons. In this paper, we analyze subcellular fractions (cytoplasm and nuclei) of rat kidney and testis with the purpose of determining the intracellular location of BASP1 and MARCKS. Western blots demonstrated that in these tissues, as in the brain, both proteins are present in the cytoplasm of the cell. According to our immunohistochemical study, BASP1 and MARCKS are specifically distributed in the tissues studied. In kidney, both proteins are present in cells located in glomeruli. In the testicular tubules, BASP1 is mainly expressed at the late stage of spermatogenesis (in spermatids) and is preserved in mature spermatozoa, while MARCKS appears equally during all stages of spermatogenesis. MARCKS is not found in mature spermatozoa. The results indicate that study of functions of BASP1 and MARCKS in the kidney and in the reproduction system holds much promise. 相似文献