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1.
Analysis of the floral transcriptome uncovers new regulators of organ determination and gene families related to flower organ differentiation in Gerbera hybrida (Asteraceae)
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Laitinen RA Immanen J Auvinen P Rudd S Alatalo E Paulin L Ainasoja M Kotilainen M Koskela S Teeri TH Elomaa P 《Genome research》2005,15(4):475-486
Development of composite inflorescences in the plant family Asteraceae has features that cannot be studied in the traditional model plants for flower development. In Gerbera hybrida, inflorescences are composed of morphologically different types of flowers tightly packed into a flower head (capitulum). Individual floral organs such as pappus bristles (sepals) are developmentally specialized, stamens are aborted in marginal flowers, petals and anthers are fused structures, and ovaries are located inferior to other floral organs. These specific features have made gerbera a rewarding target of comparative studies. Here we report the analysis of a gerbera EST database containing 16,994 cDNA sequences. Comparison of the sequences with all plant peptide sequences revealed 1656 unique sequences for gerbera not identified elsewhere within the plant kingdom. Based on the EST database, we constructed a cDNA microarray containing 9000 probes and have utilized it in identification of flower-specific genes and abundantly expressed marker genes for flower scape, pappus, stamen, and petal development. Our analysis revealed several regulatory genes with putative functions in flower-organ development. We were also able to associate a number of abundantly and specifically expressed genes with flower-organ differentiation. Gerbera is an outcrossing species, for which genetic approaches to gene discovery are not readily amenable. However, reverse genetics with the help of gene transfer has been very informative. We demonstrate here the usability of the gerbera microarray as a reliable new tool for identifying novel genes related to specific biological questions and for large-scale gene expression analysis. 相似文献
2.
Dietary carotenoids and risk of lung cancer in a pooled analysis of seven cohort studies. 总被引:5,自引:0,他引:5
Satu M?nnist? Stephanie A Smith-Warner Donna Spiegelman Demetrius Albanes Kristin Anderson Piet A van den Brandt James R Cerhan Graham Colditz Diane Feskanich Jo L Freudenheim Edward Giovannucci R Alexandra Goldbohm Saxon Graham Anthony B Miller Thomas E Rohan Jarmo Virtamo Walter C Willett David J Hunter 《Cancer epidemiology, biomarkers & prevention》2004,13(1):40-48
Intervention trials with supplemental beta-carotene have observed either no effect or a harmful effect on lung cancer risk. Because food composition databases for specific carotenoids have only become available recently, epidemiological evidence relating usual dietary levels of these carotenoids with lung cancer risk is limited. We analyzed the association between lung cancer risk and intakes of specific carotenoids using the primary data from seven cohort studies in North America and Europe. Carotenoid intakes were estimated from dietary questionnaires administered at baseline in each study. We calculated study-specific multivariate relative risks (RRs) and combined these using a random-effects model. The multivariate models included smoking history and other potential risk factors. During follow-up of up to 7-16 years across studies, 3,155 incident lung cancer cases were diagnosed among 399,765 participants. beta-Carotene intake was not associated with lung cancer risk (pooled multivariate RR = 0.98; 95% confidence interval, 0.87-1.11; highest versus lowest quintile). The RRs for alpha-carotene, lutein/zeaxanthin, and lycopene were also close to unity. beta-Cryptoxanthin intake was inversely associated with lung cancer risk (RR = 0.76; 95% confidence interval, 0.67-0.86; highest versus lowest quintile). These results did not change after adjustment for intakes of vitamin C (with or without supplements), folate (with or without supplements), and other carotenoids and multivitamin use. The associations generally were similar among never, past, or current smokers and by histological type. Although smoking is the strongest risk factor for lung cancer, greater intake of foods high in beta-cryptoxanthin, such as citrus fruit, may modestly lower the risk. 相似文献
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Sirkka Jaakkola Satu Lahti Hannele Räihä Maiju Saarinen Mimmi Tolvanen Minna Aromaa Matti Sillanpää Sakari Suominen Marja‐Leena Mattila Päivi Rautava 《European journal of oral sciences》2014,122(5):339-345
The main purpose of this study was to explore whether subjective perception of interaction with dental staff is associated with dental fear in a population‐based sample of 18‐yr‐old adolescents (n = 773). The interaction was measured using the Patient Dental Staff Interaction Questionnaire (PDSIQ), validated with exploratory and confirmatory factor analyses, which yielded the factors of ‘kind atmosphere and mutual communication’, ‘roughness’, ‘insecurity’, ‘trust and safety’, and ‘shame and guilt’. Dental fear was measured using the Modified Dental Anxiety Scale (MDAS). Gender and sense of coherence (SOC) were included as potential confounding variables. Adolescents with high dental fear more often perceived their interaction with dental staff negatively and more often felt insecure than others. This difference persisted after adjustment for gender and SOC. In conclusion, adolescents with high dental fear may perceive their interaction with dental staff more positively if the staff succeed in creating a positive, trusting, approving, and supportive atmosphere with kindness, calmness, and patience. The communication and interaction skills of dental staff may play a particularly important role when encountering highly fearful dental patients. 相似文献
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Mimmi Tolvanen Jaakko Katainen Marja-Leena Mattila Satu Lahti 《Acta odontologica Scandinavica》2014,72(2):99-105
Objective. The aim was to determine if oral health-related behavior at the age of 11–12 years predicts adolescents' educational plans at the age of 15–16 years when adjusting for gender and parents' occupational level. Materials and methods. The study population consisted of all fifth and sixth graders starting in the 2001–2002 school year in Pori, Finland (n = 1691); of these, 1467 returned properly filled questionnaires on behavior (toothbrushing and consumptions of xylitol products, candies, soft drinks and sports drinks) in 2001 and on educational plans in 2005. Parents' occupational levels were reported in 2001 by one of the parents of 1352 of these children. Associations between adolescents' educational plans and their behavior, gender and parents' occupation were evaluated using logistic regression model. Results. Children's oral health-related behavior at age 11–12, gender and parent's occupational level predicted their educational plans at age 15–16. Association between educational plans and behavior, especially cumulative health behavior, remained statistically significant when controlling for gender and parent's occupation: OR = 1.4 for difference of one good habit, and OR = 5.3 for difference of five good habits. Conclusions. Since difference in oral health-related behavior can be seen already in primary school, even when controlling for parents' occupational level, polarization of adolescents may begin already in primary school stage or even earlier. 相似文献
8.
Amina Amadou Heinz Freisling Mazda Jenab Konstantinos K. Tsilidis Antonia Trichopoulou Paolo Boffetta Bethany Van Guelpen Olatz Mokoroa Tom Wilsgaard Frank Kee Ben Schttker Jos M. Ordez-Mena Satu Mnnist Stefan Sderberg Roel C. H. Vermeulen J. Ramn Quirs Linda M. Liao Rashmi Sinha Kari Kuulasmaa Hermann Brenner Isabelle Romieu 《British journal of cancer》2021,124(11):1882
Background We investigated whether associations between prevalent diabetes and cancer risk are pertinent to older adults and whether associations differ across subgroups of age, body weight status or levels of physical activity.Methods We harmonised data from seven prospective cohort studies of older individuals in Europe and the United States participating in the CHANCES consortium. Cox proportional hazard regression was used to estimate the associations of prevalent diabetes with cancer risk (all cancers combined, and for colorectum, prostate and breast). We calculated summary risk estimates across cohorts using pooled analysis and random-effects meta-analysis.Results A total of 667,916 individuals were included with an overall median (P25–P75) age at recruitment of 62.3 (57–67) years. During a median follow-up time of 10.5 years, 114,404 total cancer cases were ascertained. Diabetes was not associated with the risk of all cancers combined (hazard ratio (HR) = 0.94; 95% confidence interval (CI): 0.86–1.04; I2 = 63.3%). Diabetes was positively associated with colorectal cancer risk in men (HR = 1.17; 95% CI: 1.08–1.26; I2 = 0%) and a similar HR in women (1.13; 95% CI: 0.82–1.56; I2 = 46%), but with a confidence interval including the null. Diabetes was inversely associated with prostate cancer risk (HR = 0.81; 95% CI: 0.77–0.85; I2 = 0%), but not with postmenopausal breast cancer (HR = 0.96; 95% CI: 0.89–1.03; I2 = 0%). In exploratory subgroup analyses, diabetes was inversely associated with prostate cancer risk only in men with overweight or obesity.Conclusions Prevalent diabetes was positively associated with colorectal cancer risk and inversely associated with prostate cancer risk in older Europeans and Americans.Subject terms: Risk factors, Cancer epidemiology 相似文献
9.
Inequality in oral health‐related quality of life before and after a major subsidization reform
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Eero Raittio Satu Lahti Urpo Kiiskinen Sari Helminen Arpo Aromaa Anna L. Suominen 《European journal of oral sciences》2015,123(4):267-275
In Finland, a dental subsidization reform, implemented in 2001–2002, abolished age restrictions on subsidized dental care. We investigated income‐related inequality in oral health‐related quality of life (OHRQoL) and its determinants among adult Finns before and after the reform. Three cross‐sectional postal surveys, focusing on perceived oral health and the use of dental services among people born before 1971, were conducted in 2001 (n = 2,046), 2004 (n = 1,728), and 2007 (n = 1,560). Five measures, based on the Oral Health Impact Profile‐14, were used as indicators of OHRQoL. Income‐related inequality and associated factors were analysed using the concentration index and its decomposition. Prevalence, extent, and severity of oral health impacts were slightly lower in 2007 than in 2001. The oral health impacts were concentrated, at all study time points, among individuals with lower income. Most of the inequality was related to self‐perceived general health, tooth loss, and income. Contributions of time since the last dental visit and satisfaction with the last treatment period to the inequality decreased from 2001 to 2007. However, the contributions of these factors were already small (10–20%) in 2001. In general, OHRQoL improved slightly; however, no clear or dramatic change in inequality in OHRQoL was seen after the reform. 相似文献
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