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101.
Inflammatory potential in relation to the microbial content of settled dust samples collected from moisture‐damaged and reference schools: results of HITEA study
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K. Huttunen J. Tirkkonen M. Täubel E. Krop S. Mikkonen J. Pekkanen D. Heederik J.‐P. Zock A. Hyvärinen M.‐R. Hirvonen 《Indoor air》2016,26(3):380-390
Aiming to identify factors causing the adverse health effects associated with moisture‐damaged indoor environments, we analyzed immunotoxicological potential of settled dust from moisture‐damaged and reference schools in relation to their microbiological composition. Mouse RAW264.7 macrophages were exposed to settled dust samples (n = 25) collected from moisture‐damaged and reference schools in Spain, the Netherlands, and Finland. After exposure, we analyzed production of inflammatory markers [nitric oxide (NO), tumor necrosis factor‐α (TNF‐)α, interleukin (IL)‐6, and macrophage inflammatory protein (MIP)2] as well as mitochondrial activity, viability, apoptosis, and cell cycle arrest. Furthermore, particle counts, concentration of selected microbial groups as well as chemical markers such as ergosterol, 3‐hydroxy fatty acids, muramic acid, endotoxins, and glucans were measured as markers of exposure. Dust from moisture‐damaged schools in Spain and the Netherlands induced stronger immunotoxicological responses compared to samples from reference schools; the responses to Finnish samples were generally lower with no difference between the schools. In multivariate analysis, IL‐6 and apoptosis responses were most strongly associated with moisture status of the school. The measured responses correlated with several microbial markers and numbers of particles, but the most important predictor of the immunotoxicological potential of settled dust was muramic acid concentration, a marker of Gram‐positive bacteria. 相似文献
102.
Common bean (Phaseolus vulgaris L.), the staple crop of Nicaragua, provides protein and nonhaem iron, but inhibitors such as phytate may prevent absorption of iron and zinc by the consumer. Warehouses in Nicaragua do not have controlled atmospheres, so beans are exposed to high temperatures and humidities that may accelerate quality loss. To evaluate the impact of 6 months of storage on quality, four national accessions of common bean were submitted to two treatments, a conventional warehouse with uncontrolled temperature and humidity, and accelerated ageing at 40 °C and 75% RH. Iron content was 61–81 mg/kg of which 3–4% was bioavailable, and zinc content was 21–25 mg/kg, of which 10–12% was bioavailable. Bioavailability generally increased in storage, significantly so in year-old INTA Linea 628 in accelerated ageing. The concentration of phytate was 8.6–9.6 mg/g and it contained 54–63% of the total phosphorus. Improvement in bioavailability of divalent cations is needed. 相似文献
103.
Pitting corrosion of M50 alloy steel bearings used in turbojet engines has been found to be a severe problem. The difficulty arises when salt-spray condensates accumulate in the engine lubricants of aircraft not in regular use. Ion implantation was applied to this problem because in the early stages of this work it was shown to be able to maintain both the dimensional stability and the contact fatigue lifetime of the M50 bearings.Qualitative tests, which simulated the geometry and thermal cycle conditions leading to pitting of the M50 bearing surface, were performed using oil containing 3 ppm NaCl. Initially it was found that chromium surface alloys containing 20–25% chromium substantially reduce the level of attack. Prior to further corrosion simulation tests, potentio-kinetic studies were carried out on M50 implanted with chromium, molybdenum and titanium in order to screen both the passivating tendency of the surface alloys formed and their resistance to localized forms of corrosion. Singular additions of chromium, molybdenum and titanium were found to increase the resistance of M50 to localized breakdown significantly. The highest resistance to localized breakdown was found for a multi-implantation of chromium and molybdenum. 相似文献
104.
Marika SUOMALAINEN Sini SUOMALAINEN Virpi PURO Vuokko KYTONIEMI Aria LAMBERG 《生命科学仪器》2010,8(6):27-30
从复杂生物基质中快速、高效地分离核酸是在获取各种实验的最佳起始原料的重要一步。磁性粒子为基础的操作流程提供了一个快速简单的解决方案,它特别适合用于自动化,在获得纯净和完整的DNA或RNA时以最少的动手时间获得良好的重现性结果。因此,必须优化基于磁珠的纯化流程来达到最高质量与数量的核酸提取。本文介绍了一个自动化、高速、以磁性粒子为基础的纯化系统来实现理想的DNA纯化方案,并考察了不同搅拌速度组合,以及在洗脱步骤的加热效应对DNA纯化数量和质量的影响。 相似文献
105.
Planar inverted-F antenna for radio frequency identification 总被引:5,自引:0,他引:5
A small and low-cost antenna solution for radio frequency identification (RFID) tags is presented. The impedance of the antenna is designed to match directly to the impedance of the RFID microchip. Also, the impedance of the antenna is immune to the platform. Thus, the antenna is applicable in many different environments. The design and measurement results are reported and discussed. 相似文献
106.
P Loula E Rauhala M Erkinjuntti E R?ty K Hirvonen V H?kkinen 《Canadian Metallurgical Quarterly》1997,3(2):89-95
We have performed a clinical phase I trial of a combination treatment with paclitaxel given as 3-hour infusion and cisplatin to determine the maximum tolerated dose and the dose-limiting toxicity in patients with recurrent or metastatic squamous cell carcinoma of the head and neck. Treatment was repeated every 21 days. Doses administered ranged from 135 mg/m2 paclitaxel/75 mg/m2 cisplatin to 250 mg/m2 paclitaxel/100 mg/m2 cisplatin. Twenty-four patients have been entered into this study. The maximum tolerated dose was determined to be 225-250 mg/m2 paclitaxel/100 mg/m2 cisplatin. The dose-limiting toxicity of this regimen was myelosuppression (granulocytopenia). Neurosensory and neuromotor toxicity was moderate. However, analyses of threshold electrotonus studies indicated subclinical neurotoxicity in most patients. One patient receiving 200 mg/m2 paclitaxel/100 mg/m2 cisplatin developed grade 3 motor-neurotoxicity. Orthostatic hypotension was observed in 8 patients receiving doses of 200 mg/m2 paclitaxel/100 mg/m2 cisplatin or higher. Objective responses were observed at paclitaxel 175 mg/m2/ cisplatin 100 mg/m2 (n = 5; complete response in 1 patient), paclitaxel 200 mg/ m2/cisplatin 100 mg/m2 (n = 3; partial response in 3 patients) and at paclitaxel 225 mg/m2/cisplatin 100 mg/m2 (n = 8; partial response in 1 patient). Eleven additional patients had stable disease. We conclude that paclitaxel administered as a 3-hour infusion followed by cisplatin is an active regimen in advanced head and neck cancer and that orthostatic hypotension may be a potentially significant clinical toxicity. 相似文献
107.
Maria Soledad Peresin Arja‐Helena Vesterinen Youssef Habibi Leena‐Sisko Johansson Joel J. Pawlak Alexander A. Nevzorov Orlando J. Rojas 《应用聚合物科学杂志》2014,131(11)
Acid‐catalyzed vapor phase esterification with maleic anhydride was used to improve the integrity and thermo‐mechanical properties of fiber webs based on poly(vinyl alcohol), PVA. The fibers were produced by electrospinning PVA from aqueous dispersions containing cellulose nanocrystals (CNCs). The effect of esterification and CNC loading on the structure and solvent resistance of the electrospun fibers was investigated. Chemical characterization of the fibers (FTIR, NMR) indicated the formation of ester bonds between hydroxyl groups belonging to neighboring molecules. Thermomechanical properties after chemical modification were analyzed using thermal gravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. An 80% improvement in the ultimate strength was achieved for CNC‐loaded, crosslinked PVA fiber webs measured at 90% air relative humidity. Besides the ultra‐high surface area, the composite PVA fiber webs were water resistant and presented excellent mechanical properties. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40334. 相似文献
108.
Fabrication of a Multifunctional Nano‐in‐micro Drug Delivery Platform by Microfluidic Templated Encapsulation of Porous Silicon in Polymer Matrix
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109.
N Jourenkova M Reinikanen C Bouchardy K Husgafvel-Pursiainen P Dayer S Benhamou A Hirvonen 《Canadian Metallurgical Quarterly》1997,7(6):515-518
BACKGROUND: Railway and subway-associated electrical trauma is rare and typically involves high voltage (> 20,000) arc injuries. Not all rail systems utilize such high voltage. We report 16 cases of electrical trauma due to 600 V direct contact with subway 'third' rails. METHODS: A case series of injured patients presenting to Shriners Burns Institute, Boston or Massachusetts General Hospital between 1970 and 1995 was retrospectively analyzed. RESULTS: A total of 16 cases was identified. Among seven subway workers, the mechanism of rail contact was unintentional by a tool, a hand or by falling; no deaths occurred. Among nine non-occupational victims, injuries involved suicide attempts, unintentional falls, or risk-taking behavior. This group suffered greater burn severity, operative procedures, and complications; three deaths occurred. CONCLUSIONS: This is the largest report series of direct electrical trauma from a subway third rail. The high morbidity and mortality from this 600 V contact suggests that the traditional classification of low voltage (< 1000 V) exposure can be subdivided to reflect the serious and lethal potential of intermediate range exposures compared to household range exposures (0-220 V). 相似文献
110.
N Jourenkova-Mironova H Wikman C Bouchardy A Voho P Dayer S Benhamou A Hirvonen 《Canadian Metallurgical Quarterly》1998,8(6):495-502
The prevalence and risk factors for nosocomial lower respiratory tract infections (LRTI) in Germany were determined as part of a national survey on nosocomial infections. The study included 14,966 patients in 72 representatively selected hospitals with departments of general medicine, surgery, obstetrics, gynecology, and intensive care units (ICU). Surveillance was carried out by four previously validated medical doctors who strictly applied the CDC-criteria for diagnosis of nosocomial infections. The overall prevalence of hospital-acquired LRTI was 0.72% with the highest rate in hospitals with more than 600 beds (1.08%) and among the patients on intensive care units (9.00%). Ventilator-associated pneumonia rates were highest in patients on ICUs (13.27). Polytrauma, impaired consciousness, chronic airway disease, prior surgery, and cardiovascular disease were significantly related to the occurrence of nosocomial LRTI. P. aeruginosa was the predominant organism causing nosocomial LRTI. Nosocomial LRTI remain a problem mainly on ICUs. Patients at risk should be monitored with extra care. 相似文献