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131.
Riikka Juntunen Aino Liukko Antti Taivainen Ale Nrvnen Guillaume Durand Anu Kauppinen Anssi Nieminen Marja Rytknen-Nissinen Soili Saarelainen Bernard Maillre Tuomas Virtanen Tuure Kinnunen 《Molecular immunology》2009,46(16):3320-3327
We have previously proposed that mammalian lipocalin allergens are recognized suboptimally by the human immune system due to their homology with endogenous lipocalins. Here, we have characterized in detail the human T cell recognition of one of the previously identified T cell epitopes of the major dog allergen Can f 1, contained in peptide p105–120. A panel of peptide analogues (altered peptide ligands, APLs) of p105–120 was tested on two specific T cell clones restricted by different human leukocyte antigen (HLA) alleles. Interestingly, we identified for both of the clones several heteroclitic APLs that were capable of stimulating them at 10–30-fold lower concentrations than the natural peptide. Moreover, one of the heteroclitic APLs identified with the T cell clones, L115F, was observed to induce a stronger polyclonal T cell response than the natural allergen peptide from the peripheral blood mononuclear cells (PBMCs) of six Can f 1-allergic subjects studied. The heteroclitic APLs bound with the same affinity as p105–120 to common HLA-DR- and HLA-DP-alleles, suggesting that their improved stimulatory capacity is attributable to a more efficient T cell receptor (TCR) recognition rather than increased HLA binding. Collectively, our data suggest that p105–120 is recognized suboptimally by human T cells. This may contribute to the allergenicity of Can f 1. 相似文献
132.
Marianna Virtanen Jane E. Ferrie David Gimeno Jussi Vahtera Marko Elovainio Archana Singh-Manoux Michael G. Marmot Mika Kivim?ki 《Sleep》2009,32(6):737-745
Study Objective:
To examine whether exposure to long working hours predicts various forms of sleep disturbance; short sleep, difficulty falling asleep, frequent waking, early waking and waking without feeling refreshed.Design:
Prospective study with 2 measurements of working hours (phase 3, 1991–1994 and phase 5, 1997–1999) and 2 measurements of subjective sleep disturbances (phase 5 and phase 7, 2002–2004).Setting:
The Whitehall II study of British civil servants.Participants:
Full time workers free of sleep disturbances at phase 5 and employed at phases 5 and 7 (n = 937–1594) or at phases 3, 5, and 7 (n = 886–1510).Measurements and Results:
Working more than 55 hours a week, compared with working 35–40 hours a week, was related to incident sleep disturbances; demographics-adjusted odds ratio (95% CI) 1.98 (1.05, 3.76) for shortened sleeping hours, 3.68 (1.58, 8.58) for difficulty falling asleep; and 1.98 (1.04, 3.77) for waking without feeling refreshed. Repeat exposure to long working hours was associated with odds ratio 3.24 (1.45, 7.27) for shortened sleep, 6.66 (2.64, 16.83) for difficulty falling asleep, and 2.23 (1.16, 4.31) for early morning awakenings. Some associations were attenuated after adjustment for other risk factors. To a great extent, similar results were obtained using working hours as a continuous variable. Imputation of missing values supported the findings on shortened sleep and difficulty in falling asleep.Conclusion:
Working long hours appears to be a risk factor for the development of shortened sleeping hours and difficulty falling asleep.Citation:
Virtanen M; Ferrie JE; Vahtera J; Elovainio M; Singh-Manoux A; Marmot MG; Kivimäki M. Long working hours and sleep disturbances: the whitehall II prospective cohort study. SLEEP 2009;32(6):737–745. 相似文献133.
H. Kersten D. Bearn S. Gundersen P. Holbrook N. Kotsanos M. Radnai J. Virtanen 《European journal of dental education》2010,14(1):35-42
In the Bologna process a third cycle is distinguished at the doctoral level. In documents on the Bologna process it is advocated to harmonise the structure and requirements of the doctorate, which in Europe are characterised by a wide variety. Differences exist in all possible requirements between countries, and even between schools within one country differences can be seen. In this paper an inventory is made of these differences in the dental doctorate between European countries. Moreover, the need for necessary harmonisation of requirements for a European dental doctorate is strongly advocated and a proposal is presented. 相似文献
134.
135.
Marianna Virtanen Minna Pietik?inen Mika Kivim?ki Pauliina Luopa Jukka Jokela Marko Elovainio Jussi Vahtera 《BMC public health》2009,9(1):382
Background
This study compared parental smoking with school personnel smoking in relation to adolescents' smoking behaviours, alcohol use, and illicit drug use. 相似文献136.
Diet does not explain the high prevalence of dyslipidaemia in paediatric renal transplant recipients
Siirtola A Virtanen SM Ala-Houhala M Koivisto AM Solakivi T Lehtimäki T Holmberg C Antikainen M Salo MK 《Pediatric nephrology (Berlin, Germany)》2008,23(2):297-305
Dyslipidaemia exists frequently after renal transplantation (RTx) and promotes atherosclerosis. In this study, we examined
the association between daily intake of nutrients and serum lipids after paediatric RTx. We studied 45 children with acceptably
functioning kidney grafts and adequately completed food records at a median age of 10.6 years (range 4.3–17.2 years), a median
5.2 years (range 1.0–11.0) after RTx, and 178 healthy controls at a median age of 9.0 years (range 3.2–18.7 years). Serum
total cholesterol (TC), triglyceride, and apolipoprotein B concentrations were higher in the RTx patients than in the controls
(P < 0.001), despite similar dietary intakes of saturated and polyunsaturated fats, and cholesterol. Both the RTx patients and
controls ingested a low amount of polyunsaturated fats [mean (SD) percent of total calories (E%) 4.8 (1.3) and 4.6 (1.5),
respectively] and an excessive amount of saturated fats [mean (SD) E% 14.4 (2.4) and 14.1 (2.8), respectively]. In multiple
regression analyses, dietary fibre was negatively associated with serum TC concentration. The standard deviation score for
body mass index was negatively associated with serum concentration of high-density lipoprotein cholesterol (HDL-C) and low-density
lipoprotein diameter, and positively with serum triglyceride concentration. In addition, dietary total fat intake was positively
associated with serum HDL-C. In conclusion, the higher prevalence of dyslipidaemia in our paediatric RTx patients than in
the controls was not explained by the diet. However, the type of fat consumed implicates the counselling for a healthier dietary
lifestyle, with an increase in the ingestion of polyunsaturated fats and a decrease in that of saturated fats. 相似文献
137.
Pulse-lavage washing is an effective method for defatting of morselized allograft bone in the operating theater 总被引:1,自引:0,他引:1
Background and purpose Incorporation of fresh-frozen allograft bone and safety aspects associated with this procedure can be improved by removing blood and lipids from the bone. We investigated in a quantitative manner how efficient pulse lavage might be for removal of adipose tissue from morselized allograft bone.
Methods Depending on the study, the washing was performed with an average of 0.8 L or 1.6 L of sterile saline at room temperature. Fat content of the morselized bone samples was determined using hexane elution. The efficiency of pulse lavage alone was compared with that after an additional wash in 12 L of warm water (55°C). Unprocessed controls were also included for comparison.
Results Pulse lavage with 0.8 L saline alone removed 80% of the fat from the bone, whereas 95% of the fat was removed when washing was performed with 1.6 L of saline. The cleansing efficacy was improved further when an additional wash with warm water was used.
Interpretation Our results indicate that pulse-lavage washing alone at room temperature is an effective method for defatting of morselized allograft bone, but an additional wash with warm water improves the cleansing efficiency. Pulse lavage is easily available and simple to use in the operating theater. 相似文献
Methods Depending on the study, the washing was performed with an average of 0.8 L or 1.6 L of sterile saline at room temperature. Fat content of the morselized bone samples was determined using hexane elution. The efficiency of pulse lavage alone was compared with that after an additional wash in 12 L of warm water (55°C). Unprocessed controls were also included for comparison.
Results Pulse lavage with 0.8 L saline alone removed 80% of the fat from the bone, whereas 95% of the fat was removed when washing was performed with 1.6 L of saline. The cleansing efficacy was improved further when an additional wash with warm water was used.
Interpretation Our results indicate that pulse-lavage washing alone at room temperature is an effective method for defatting of morselized allograft bone, but an additional wash with warm water improves the cleansing efficiency. Pulse lavage is easily available and simple to use in the operating theater. 相似文献
138.
139.
Sallinen J Höglund I Engström M Lehtimäki J Virtanen R Sirviö J Wurster S Savola JM Haapalinna A 《British journal of pharmacology》2007,150(4):391-402
BACKGROUND AND PURPOSE: Pharmacological validation of novel functions for the alpha2A-, alpha2B-, and alpha2C-adrenoceptor (AR) subtypes has been hampered by the limited specificity and subtype-selectivity of available ligands. The current study describes a novel highly selective alpha2C-adrenoceptor antagonist, JP-1302 (acridin-9-yl-[4-(4-methylpiperazin-1-yl)-phenyl]amine). EXPERIMENTAL APPROACH: Standard in vitro binding and antagonism assays were employed to demonstrate the alpha2C-AR specificity of JP-1302. In addition, JP-1302 was tested in the forced swimming test (FST) and the prepulse-inhibition of startle reflex (PPI) model because mice with genetically altered alpha2C-adrenoceptors have previously been shown to exhibit different reactivity in these tests when compared to wild-type controls. KEY RESULTS: JP-1302 displayed antagonism potencies (KB values) of 1,500, 2,200 and 16 nM at the human alpha2A-, alpha2B-, and alpha2C-adrenoceptor subtypes, respectively. JP-1302 produced antidepressant and antipsychotic-like effects, i.e. it effectively reduced immobility in the FST and reversed the phencyclidine-induced PPI deficit. Unlike the alpha2-subtype non-selective antagonist atipamezole, JP-1302 was not able to antagonize alpha2-agonist-induced sedation (measured as inhibition of spontaneous locomotor activity), hypothermia, alpha2-agonist-induced mydriasis or inhibition of vas deferens contractions, effects that have been generally attributed to the alpha2A-adrenoceptor subtype. In contrast to JP-1302, atipamezole did not antagonize the PCP-induced prepulse-inhibition deficit. CONCLUSIONS AND IMPLICATIONS: The results provide further support for the hypothesis that specific antagonism of the alpha2C-adrenoceptor may have therapeutic potential as a novel mechanism for the treatment of neuropsychiatric disorders. 相似文献
140.
Lee JE Hunter DJ Spiegelman D Adami HO Albanes D Bernstein L van den Brandt PA Buring JE Cho E Folsom AR Freudenheim JL Giovannucci E Graham S Horn-Ross PL Leitzmann MF McCullough ML Miller AB Parker AS Rodriguez C Rohan TE Schatzkin A Schouten LJ Virtanen M Willett WC Wolk A Zhang SM Smith-Warner SA 《Journal of the National Cancer Institute》2007,99(10):801-810