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41.
BACKGROUND AND AIMS: In a few, earlier, uncontrolled trials, alleviation of chronic pain has been documented by vitamin D supplementation. This randomized double-blind placebo controlled trial addressed the association between pain and vitamin D deficiency and the effects of vitamin D supplementation on pain in institutionalized aged patients. METHODS: 216 long-term care patients were enrolled in Helsinki, Finland. Pain was assessed by three tools: Resident Assessment Instrument (RAI), Discomfort Behavior Scale, and Pain Assessment in Advanced Dementia Scale. Scores for Cognitive Performance Scale (CPS) and other clinical assessments were also collected from the RAI-database. Levels of 25-hydroxyvitamin D (25- OHD) and parathyroid hormone were also determined. Patients in pain (n=202) were randomized into three treatment groups, each receiving 0, 400, or 1200 IU cholecalciferol per day, respectively. Assessments were repeated after six-month vitamin D supplementation. RESULTS: Patients were aged (84.5+/-7.5 yrs), demented (CPS= 4.9+/-1.4, range 1-6), and chronically bedridden. Pain was present in 38.4% to 83.8% of patients depending on assessment tool. Low 25-OHD levels (<50 nmol/L) were very common (98.1%). However, vitamin D deficiency was not associated with pain or pain behavior. The supplementation resulted in a marked increase in 25-OHD levels. However, neither prevalence of painlessness nor pain scores changed significantly after vitamin D supplementation. CONCLUSIONS: We were not able either to show an association between vitamin D deficiency and pain or to observe alleviation of pain by vitamin D supplementation. The independent role of vitamin D in the etiology of pain remains controversial. 相似文献
42.
Niina Onnela Leena Lehtonen Mikko Koski Jari Hyttinen 《Medical & biological engineering & computing》2013,51(1-2):61-70
The purpose of this study is to develop and test a method to reveal if the retinal pigment epithelium (RPE) cells differentiated from human embryonic stem cells (hESC) support the functions of photoreceptors. hESC-derived RPE (hESC–RPE) cells offer a potent cell source for cell replacement therapy that may be used to prevent certain eye diseases. Methods to assure the functionality of the RPE cells are well warranted. Electroretinograms (ERG) measure the electrophysiological response of the retina to light stimuli. A setup was developed that enables the measurement of ERG in vitro from mice retinas cultured together with hESC–RPE cells. The co-culture of RPE and retinas seems to be a viable tool to assess the functionality of RPE in vitro. However, owing to limited sample size results were somewhat mixed, and thus it was not possible to prove that hESC–RPE cells enhance the ERG response of a mouse retina in vitro. The long-term culturing of the retinas needs to be refined to acquire more conclusive evidence of the supporting role of the RPE and to explore the full potential of the co-culture and ERG methods in assessing RPE functionality. 相似文献
43.
Anu Muraja‐Murro Antti Kulkas Mikko Hiltunen Salla Kupari Taina Hukkanen Pekka Tiihonen Esa Mervaala Juha Töyräs 《Journal of sleep research》2013,22(6):663-669
Obstructive sleep apnea (OSA) is linked to an increased mortality rate. However, the severity of individual obstruction events is rarely considered quantitatively in clinical practice. We hypothesized that OSA with especially severe obstruction events would predispose a patient to greater health risks than OSA with a similar apnea–hypopnea index (AHI), but lower severity of individual events. This hypothesis was tested in a follow‐up (198.2 ± 24.7 months) of a population of 1068 men referred for ambulatory polygraphic recording due to suspected OSA. The recordings were analysed according to the guidelines of the American Academy of Sleep Medicine. Furthermore, a novel obstruction severity parameter was determined; this was defined as the product of duration of the individual obstruction event and area of the related desaturation event. Patients treated with continuous positive airway pressure (CPAP) were omitted. We identified 125 deceased patients from our original population and for 113 of these a matching alive patient with similar AHI, age, body mass index (BMI), smoking habits and follow‐up time could be found. The deceased patients with severe OSA (based on conventional AHI) showed higher obstruction severity values than their AHI‐matched alive controls. Based on the multivariate logistic regression analysis, obstruction severity was the only parameter which was related statistically significantly to mortality in the severe OSA category. Furthermore, 59% of all deceased patients and 83% of those who had severe OSA displayed higher obstruction severity than the AHI‐matched alive counterparts. To conclude, the obstruction severity parameter provided valuable prognostic information supplementing AHI. The obstruction severity parameter might improve recognition of the patients with the highest risk. 相似文献
44.
Converting from CT- to MRI-only-based target definition in radiotherapy of localized prostate cancer
45.
Kai O. Lindros Ph.D. Pentti Sipponen M.D. Pekka Pikkarainen M.D. Ulla Turunen M.D. Mikko Salaspuro M.D. 《Alcoholism, clinical and experimental research》1979,3(1):78-82
Rats chronically fed ethanol developed liver injury only if they also received low doses of the alcohol dehydrogenase inhibitor, 4-methylpyrazole, suggesting that the consistency of the influence of ethanol and its metabolism, rather than the level of acetaldehyde or the degree of the metabolic effects, contributes to the pathogenesis of alcoholic liver damage. 相似文献
46.
Annika Mutanen Jouko Lohi Laura Merras-Salmio Antti Koivusalo Mikko P. Pakarinen 《Journal of hepatology》2021,74(3):593-602
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47.
Alava M Ardelius J Aurell E Kaski P Krishnamurthy S Orponen P Seitz S 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(40):15253-15257
We study the performance of stochastic local search algorithms for random instances of the K-satisfiability (K-SAT) problem. We present a stochastic local search algorithm, ChainSAT, which moves in the energy landscape of a problem instance by never going upwards in energy. ChainSAT is a focused algorithm in the sense that it focuses on variables occurring in unsatisfied clauses. We show by extensive numerical investigations that ChainSAT and other focused algorithms solve large K-SAT instances almost surely in linear time, up to high clause-to-variable ratios alpha; for example, for K = 4 we observe linear-time performance well beyond the recently postulated clustering and condensation transitions in the solution space. The performance of ChainSAT is a surprise given that by design the algorithm gets trapped into the first local energy minimum it encounters, yet no such minima are encountered. We also study the geometry of the solution space as accessed by stochastic local search algorithms. 相似文献
48.
Possible role for mast cell-derived cathepsin G in the adverse remodelling of stenotic aortic valves 总被引:1,自引:1,他引:1
Helske Satu; Syvaranta Suvi; Kupari Markku; Lappalainen Jani; Laine Mika; Lommi Jyri; Turto Heikki; Mayranpaa Mikko; Werkkala Kalervo; Kovanen Petri T.; Lindstedt Ken A. 《European heart journal》2006,27(12):1495-1504
Aims Aortic stenosis (AS) is characterized by extensive remodellingof the valves, including infiltration of inflammatory cells,extracellular matrix degradation, and fibrosis. The molecularmechanisms behind this adverse remodelling have remained obscure.In this article, we study whether cathepsin G, an angiotensinII (Ang II)-forming elastolytic enzyme, contributes to progressionof AS. Methods and results Stenotic aortic valves (n=86) and controlvalves (n=17) were analysed for cathepsin G, transforming growthfactor-ß1 (TGF-ß1), and collagens I andIII with RTPCR and immunohistochemistry. Valvular collagen/elastinratio was quantified by histochemistry. In stenotic valves,cathepsin G was present in mast cells and showed increased expression(P<0.001), which correlated positively (P<0.001) withthe expression levels of TGF-ß1 and collagens I andIII. TGF-ß1 was also present in mast cell-rich areasand cathepsin G induced losartan-sensitive TGF-ß1expression in cultured fibroblasts. Collagen/elastin ratio wasincreased in stenotic valves (P<0.001) and correlated positivelywith smoking (P=0.02). Nicotine in cigarette smoke activatedmast cells and induced TGF-ß1 expression in culturedfibroblasts. Fragmented elastin was observed in stenotic valvescontaining activated cathepsin G-secreting mast cells and innormal valves treated with cathepsin G. Conclusion In stenotic aortic valves, mast cell-derived cathepsinG may cause adverse valve remodelling and AS progression. 相似文献
49.
Carotid artery intima-media thickness in Finnish families with familial combined hyperlipidemia 总被引:3,自引:0,他引:3
BACKGROUND: Familial combined hyperlipidemia (FCHL) is the most common hereditary lipid disorder that predisposes the patients to premature coronary heart disease. Members of FCHL families are categorised as affected or unaffected according to serum lipid levels. This study is aimed to evaluate whether there is a difference in carotid artery wall thickness between asymptomatic FCHL family members who are affected and those who are unaffected according to the currently used lipid criteria. METHODS AND RESULTS: Carotid artery ultrasonography with intima-media thickness (IMT) measurements was performed for 148 members of 39 Finnish FCHL families. Study subjects who had no history of coronary heart disease or stroke were divided into two groups according to their serum total cholesterol and/or triglyceride levels. The average carotid IMT of the affected subjects (0.75+/-0.15 mm) was not significantly different from that of their unaffected relatives (0.73+/-0.13 mm), P=0.90. In multivariate analysis, age, gender, and pulse pressure, but no lipid variables, contributed significantly to the variation of carotid IMT. CONCLUSIONS: The IMT findings in FCHL family members indicate that the current lipid criteria alone are of limited value in predicting long-term risk of cardiovascular disease in asymptomatic members of FCHL families. 相似文献