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21.
David ST Chandran U Paquette D Scholten D Wilson J Galanis E Becker M Crane F Lester R Mersereau T Wong E Carr D 《Chronic diseases in Canada》2005,26(2-3):59-64
Attendance at summer outdoor mass gatherings may lead to heat- and sun-related illness. The purposes of this study were: (1) to estimate the proportion of people in attendance at the 2003 Canada Day celebration in the National Capital Region who used sun and heat protective items; (2) to identify factors associated with the utilization of these protective items; and (3) to provide research data to public outdoor event organizers when developing evidence-based plans for safer events. A naturalistic observational cross-sectional method was used to gather information at the 2003 Canada Day celebration in the National Capital Region on attendees' demographics, the sun and heat protective items they used and the protective resources available at the event sites. Of the 398 observed attendees, the proportion using any one of the protective items ranged from 3 percent (an open umbrella) to 51.5 percent (sunglasses). Females were more likely to use protective items more than males, and adults more likely than children. Planners of public outdoor events should consider the factors that influence the utilization of sun and heat protective behaviours and the environmental modifications that would allow participants to make safe choices. 相似文献
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Role of copper in mitochondrial iron metabolism 总被引:1,自引:1,他引:1
Heme synthesis by copper-deficient cells was investigated to elucidate the nature of the defect in intracellular iron metabolism. Iron uptake from transferrin by copper-deficient reticulocytes was 52% of normal, and the rate of heme synthesis was 33% of normal. Hepatic mitochondria isolated from copper-deficient animals were deficient in cytochrome oxidase activity and failed to synthesize heme from ferric iron (Fe III) and protoporphyrin at the normal rate. The rate of heme synthesis correlated with the cytochrome oxidase activity. Heme synthesis from Fe(III) and protoporphyrin by normal mitochondria was enhanced by succinate and inhibited by malonate, antimycin A, azide, and cyanide. It is proposed that an intact electron transport system is required for the reduction of Fe(III), thereby providing a pool of ferrous iron (Fe II) for protoheme and heme a synthesis. 相似文献
24.
A.W. Turksma H.J. Bontkes J.J. Ruizendaal H. van den Heuvel K.B.J. Scholten S.J.A.M. Santegoets T.D. de Gruijl C.J.L.M. Meijer E. Hooijberg 《Human immunology》2013
Monocyte derived dendritic cells (moDC) electroporated with tumor associated antigen derived mRNA can elicit specific T cells against tumor cells in vivo. IL21 has been shown to enhance activation and cytotoxicity in CD8+ T cells. We therefore investigated in vitro effects on human CD8+ T-cells after stimulation with IL21 mRNA electroporated moDC. Codon modification of the IL21 gene significantly enhanced IL21 production upon electroporation of moDC. Tumor associated antigen specific CTL induction efficiency was significantly enhanced when codon modified IL21 mRNA was co-electroporated with tumor associated antigen mRNA. Tumor associated antigen specific T cells induced by codon modified IL21-DC demonstrated increased cytotoxic capacity and killing compared to control cultures. In conclusion, ectopic expression of codon modified IL21 by moDC enhances the priming efficiency of the DC as well as the cytotoxic potential of the induced CTL. 相似文献
25.
Michele Stürmer Isadora M. Garcia Virgínia S. Souza Fernanda Visioli Jackson D. Scholten Susana M.W. Samuel Vicente C.B. Leitune Fabrício M. Collares 《Dental materials》2021,37(2):223-235
ObjectiveFormulate experimental adhesives containing titanium dioxide nanotubes (nt-TiO2) or titanium dioxide nanotubes with a triazine-methacrylate monomer (nt-TiO2:TAT) and evaluate the effect of these fillers on the physical, chemical, and biological properties of the adhesives.MethodsFirst, nt-TiO2 were synthesized via a hydrothermal method. The nt-TiO2 were mixed with a triazine-methacrylate monomer (TAT) to formulate nt-TiO2:TAT, which were characterized by transmission electron microscopy (TEM). The nt-TiO2, TAT, and nt-TiO2:TAT were evaluated via Fourier Transform Infrared, Ultraviolet–visible, and micro-Raman spectroscopies. An experimental adhesive resin was formulated with bisphenol A glycerolate dimethacrylates, 2-hydroxyethyl methacrylate, and photoinitiator/co-initiator system. nt-TiO2 or nt-TiO2:TAT were incorporated at 2.5 wt.% and 5 wt.% in the adhesive. The base resin without nt-TiO2 or nt-TiO2:TAT was used as a control group. The adhesives were evaluated for antibacterial activity, cytotoxicity, polymerization kinetics, degree of conversion (DC), Knoop hardness, softening in solvent (ΔKHN%), ultimate tensile strength (UTS), 24 h- and 1 year- microtensile bond strength (μ-TBS).ResultsTEM confirmed the nanotubular morphology of TiO2. FTIR, UV–vis, and micro-Raman analyses showed the characteristic peaks of each material, indicating the impregnation of TAT in the nt-TiO2. Adhesives with nt-TiO2:TAT showed antimicrobial activity against biofilm formation compared to control (p < 0.05), without differences in the viability of planktonic bacteria (p > 0.05). All groups showed high percentages of pulp cell viability. The polymerization kinetics varied among groups, but all presented DC above 50%. The addition of 5 wt.% of nt-TiO2 and both groups containing nt-TiO2:TAT showed higher values ??of Knoop hardness compared to the control (p < 0.05). The groups with nt-TiO2:TAT presented lower ΔKHN% (p < 0.05) and higher UTS (p < 0.05) than the control group. After one year, the group with 5 wt.% of nt-TiO2, as well as both groups containing nt-TiO2:TAT, showed higher μ-TBS than the control (p < 0.05).SignificanceThe mixing of a triazine-methacrylate monomer with the nt-TiO2 generated a filler that improved the physicochemical properties of the adhesive resins and provided antibacterial activity, which could assist in preventing carious lesions around tooth-resin interfaces. The set of physical, chemical, and biological properties of the formulated polymer, together with the greater stability of the bond strength over time, make nt-TiO2:TAT a promising filler for dental adhesive resins. 相似文献
26.
Annemieke H. Starrenburg Karin Kraaier Susanne S. Pedersen Moniek van Hout Marcoen Scholten Job van der Palen 《International journal of behavioral medicine》2013,20(3):425-433
Background
Personality factors and psychiatric history may help explain individual differences in risk of psychological morbidity and poor health outcomes in patients with an implantable cardioverter defibrillator (ICD).Purpose
We examined associations between previous anxiety and depressive disorder, type D personality, anxiety or depressive symptoms, and health status in ICD patients prior to ICD implantation.Method
Patients (N?=?278; 83 % men; mean age?=?62.2 years ±11) receiving a first ICD from September 2007 through April 2010 at the Medisch Spectrum Twente, The Netherlands completed validated questionnaires before implantation assessing type D personality (14-item Type D Scale), anxiety and depressive symptoms (Hospital Anxiety and Depression Scale), and health status (36-item Short Form Health Survey). History of anxiety or depressive disorder was assessed with the Mini International Neuropsychiatric Interview structural interview.Results
Previous anxiety or depressive disorder was prevalent in 8 and 19 % of patients, respectively. Type D personality was present in 21 %, depressive symptoms in 15 %, and anxiety in 24 %. In adjusted analyses, type D personality was a dominant correlate of previous depressive disorder (odds ratio (OR) 6.2, p?<?0.001) and previous anxiety disorder (OR 3.9, p?=?0.004). Type D personality (OR 4.0, p?<?0.001), age (OR 1.03, p?=?0.043), and gender (OR 2.5, p?=?0.013) were associated with anxiety symptoms at baseline. Type D personality (OR 5.9. p?<?0.001) was also associated with increased depressive symptoms at baseline. Heart failure and type D personality were related to poorer health status.Conclusion
In ICD patients, prior to ICD implantation, a previous anxiety or depressive disorder, type D personality, and anxiety and depressive symptoms were associated with poorer health status. Type D personality was also independently associated with increased anxiety and depression symptoms. 相似文献27.
28.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献
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