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Juho-Antti Junno Markus Paananen Jaro Karppinen Tuija Tammelin Jaakko Niinimäki Eveliina Lammentausta Markku Niskanen Miika T. Nieminen Marjo-Riitta Järvelin Jani Takatalo Osmo Tervonen Juha Tuukkanen 《The spine journal》2013,13(2):184-189
Background contextReduced vertebral strength is a clear risk factor for vertebral fractures. Men and women with vertebral fractures often have reduced vertebral size and bone mineral density (BMD). Vertebral strength is controlled by both genetic and developmental factors. Malnutrition and low levels of physical activity are commonly considered to result in reduced bone size during growth. Several studies have also demonstrated the general relationship between BMD and physical activity in the appendicular skeleton.PurposeIn this study, we wanted to clarify the role of physical activity on vertebral bodies. Vertebral dimensions appear to generally be less pliant than long bones when lifetime changes occur. We wanted to explore the association between physical activity during late adolescence and vertebral strength parameters such as cross-sectional size and BMD.Study designThe association between physical activity and vertebral strength was explored by measuring vertebral strength parameters and defining the level of physical activity during adolescence.Patient sampleThe study population consisted of 6,928 males and females who, at 15 to 16 and 19 years of age, responded to a mailed questionnaire inquiring about their physical activity. A total of 558 individuals at the mean age of 21 years underwent magnetic resonance imaging (MRI) scans.MethodsWe measured the dimensions of the fourth lumbar vertebra from the MRI scans of the Northern Finland Birth Cohort 1986 and performed T2* relaxation time mapping, reflective of BMD. Vertebral strength was based on these two parameters. We analyzed the association of physical activity on vertebral strength using the analysis of variance.Results and conclusionsWe observed no association between the level of physical activity during late adolescence and vertebral strength at 21 years. 相似文献
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Pia Pajunen Mikko Syvänne Graciela Castro Markku S. Nieminen Marja-Riitta Taskinen 《Scandinavian cardiovascular journal : SCJ》2013,47(2):96-100
Objective - To investigate the relation between severity and extent of coronary artery disease (CAD) and in vitro cholesterol efflux capacity. Design - This study consisted of 46 type 2 diabetic, and 42 nondiabetic men undergoing coronary angiography. Quantitative coronary angiography was used to estimate the severity, extent, and overall "atheroma burden" of CAD. The capacity of patient plasma to induce cholesterol efflux from cultured Fu5AH rat hepatoma cells was measured in vitro. Results - In the combined study population (n = 88), there was a significant inverse correlation between efflux and global atheroma burden (r = -0.23, p < 0.05). In the diabetic group, the global atheroma burden index was independently associated both with cholesterol efflux and with LpA-I levels. However, in the nondiabetic CAD group this association was lost when efflux and LpA-I levels were included in the same model. Conclusion - The present study demonstrated that efflux capacity was inversely associated with the severity and extent of CAD. In the diabetic group this association was independent of LpA-I levels, suggesting impaired antiatherogenic potential of these particles in type 2 diabetic patients. 相似文献
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Esa J?msen Timo Puolakka Antti Eskelinen Pirkko J?ntti Jarkko Kalliovalkama Jyrki Nieminen Jaakko Valvanne 《Acta orthopaedica》2013,84(1):44-53
Background and purpose High age is associated with increased postoperative mortality, but the factors that predict mortality in older hip and knee replacement recipients are not known. Methods Preoperative clinical and operative data on 1,998 primary total hip and knee replacements performed for osteoarthritis in patients aged ≥ 75 years in a single institution were collected from a joint replacement database and compoared with mortality data. Average follow-up was 4.2 (2.2–7.6) years for the patients who survived. Factors associated with mortality were analyzed using Cox regression analysis, with adjustment for age, sex, operated joint, laterality, and anesthesiological risk score. Results Mortality was 0.15% at 30 days, 0.35% at 90 days, 1.60% at 1 year, 7.6% at 3 years, and 16% at 5 years, and was similar following hip and knee replacement. Higher age, male sex, American Society of Anesthesiologists risk score of > 2, use of walking aids, preoperative walking restriction (inability to walk or ability to walk indoors only, compared to ability to walk > 1 km), poor clinical condition preoperatively (based on clinical hip and knee scores or clinical severity of osteoarthritis), preoperative anemia, severe renal insufficiency, and use of blood transfusions were associated with higher mortality. High body mass index had a protective effect in patients after hip replacement. Interpretation Postoperative mortality is low in healthy old joint replacement recipients. Comorbidities and functional limitations preoperatively are associated with higher mortality and warrant careful consideration before proceeding with joint replacement surgery. 相似文献
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Matloob Ahmad Sana Aslam Mujahid Hussain Bukhari Catherine Montero Mervi Detorio Masood Parvez Raymond F. Schinazi 《Medicinal chemistry research》2014,23(3):1309-1319
A new series of pyrazolobenzothiazine-based carbohydrazides was prepared in a facile way, starting with commercially available sodium saccharine. The final products were sufficiently characterized by spectroscopic techniques. In addition, compound 5k was confirmed with X-ray crystallography as well. All the compounds were screened for anti-HIV-1 and cytotoxicity activities. Overall, out of 15 compounds, seven exhibited good activity with EC50 values <20 μM. Compounds 5c, 5d, 5g, 5j and 5k appeared as the potent anti-HIV-1 agents with EC50 values <5.0 μM. The structure–activity relationship would facilitate the discovery of new molecules with better profile of HIV inhibition activity. 相似文献
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Mental health service users (MHSUs) often face difficulties in achieving successful participation in education; however, the tools that could help them succeed are rarely investigated. This study aimed to illuminate the experiences of MHSUs in an education intervention based on a European Union (EU) project. Their experiences are compared across nine EU countries. The data were collected through individual interviews with MHSUs (n = 47) at day activity centres that provide mental health services. An inductive content analysis was used as the method of analysis. Three main categories, which include seven subcategories, are revealed by the analysis. The main categories are as follows: (i) the factors related to MHSUs’ educational preparedness, (ii) the dimensions of the learning environment, and (iii) the effects of training intervention. The MHSUs’ experiences with the education intervention were similar across all countries. The findings showed that this education intervention is a multidimensional process. It contains social, mental, and physical dimensions linked to a learner and learning environment. These dimensions influence the MHSUs’ ability to participate in the education process. At its best, the education intervention supports the personal growth of MHSUs and prepares them for social integration. An education intervention can be a usable tool in the rehabilitation of MHSUs if the multidimensional nature of education is taken into consideration. Therefore, designing and executing education interventions requires the attendance of the MHSUs in cooperation with mental health and education professionals. Our findings suggest a tentative framework that can be used in designing and executing education for MHSUs. 相似文献
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Kaisa Nieminen Juha Immanen Marjukka Laxell Leila Kauppinen Petr Tarkowski Karel Dolezal Sari Thtiharju Annakaisa Elo Mlanie Decourteix Karin Ljung Rishikesh Bhalerao Kaija Keinonen Victor A. Albert Yk Helariutta 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(50):20032-20037
Although a substantial proportion of plant biomass originates from the activity of vascular cambium, the molecular basis of radial plant growth is still largely unknown. To address whether cytokinins are required for cambial activity, we studied cytokinin signaling across the cambial zones of 2 tree species, poplar (Populus trichocarpa) and birch (Betula pendula). We observed an expression peak for genes encoding cytokinin receptors in the dividing cambial cells. We reduced cytokinin levels endogenously by engineering transgenic poplar trees (P. tremula × tremuloides) to express a cytokinin catabolic gene, Arabidopsis CYTOKININ OXIDASE 2, under the promoter of a birch CYTOKININ RECEPTOR 1 gene. Transgenic trees showed reduced concentration of a biologically active cytokinin, correlating with impaired cytokinin responsiveness. In these trees, both apical and radial growth was compromised. However, radial growth was more affected, as illustrated by a thinner stem diameter than in WT at same height. To dissect radial from apical growth inhibition, we performed a reciprocal grafting experiment. WT scion outgrew the diameter of transgenic stock, implicating cytokinin activity as a direct determinant of radial growth. The reduced radial growth correlated with a reduced number of cambial cell layers. Moreover, expression of a cytokinin primary response gene was dramatically reduced in the thin-stemmed transgenic trees. Thus, a reduced level of cytokinin signaling is the primary basis for the impaired cambial growth observed. Together, our results show that cytokinins are major hormonal regulators required for cambial development. 相似文献
50.
Melatonin affects food intake, body mass and adiposity of several mammals, but the effects of melatonin on energy metabolism remain largely unknown. This study investigated subacute effects of persistent melatonin treatment and continuous light on carbohydrate and fat metabolism of rat liver and kidney. The male and female rats (no.=40) were maintained either in 12L:12D photoperiod or in constant light. Half the rats in both lighting conditions were treated with continuous-release melatonin implants. Liver lipid concentrations, liver and kidney glucose-6-phosphatase, glycogen phosphorylase and lipase esterase activities, glycogen contents as well as plasma T4, T3, insulin, glucose and melatonin concentrations were determined. There was clear sexual dimorphism in the responses to exogenous melatonin and constant light. Continuous light stimulated carbohydrate metabolism of rat liver. Exogenous melatonin enhanced utilization of liver carbohydrates but suppressed hepatic lipolysis. Changes in normal circulating melatonin concentrations led to enhanced utilization of kidney carbohydrates supporting a role for melatonin in renal function. Both exogenous melatonin and constant light seem to have a strong regulatory effect on rat energy metabolism. 相似文献