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31.
Honsell G De Bortoli M Boscolo S Dell'Aversano C Battocchi C Fontanive G Penna A Berti F Sosa S Yasumoto T Ciminiello P Poli M Tubaro A 《Environmental science & technology》2011,45(16):7051-7059
Ostreopsis cf. ovata, a benthic dinoflagellate often blooming along the Mediterranean coasts, has been associated with toxic events ranging from dyspnea to mild dermatitis. In late September 2009, an Ostreopsis cf. ovata bloom occurred in the Gulf of Trieste (Northern Adriatic Sea; Italy), causing pruritus and mild dermatitis in beachgoers. An integrated study was initiated to characterize Ostreopsis cells by light and confocal microscopy, PCR techniques, immunocytochemistry, and high resolution liquid chromatography-mass spectrometry (HR LC-MS). The presence of Ostreopsis cf. ovata of the Atlantic/Mediterranean clade was unambiguously established by morphological and genetic analyses in field samples. Several palytoxin-like compounds (ovatoxin-a,-b,-c,-d,-e) were identified by HR LC-MS, ovatoxin-a being the most abundant (45-64 pg/cell). Surprisingly, no palytoxin was detected. For the first time, monoclonal and polyclonal antipalytoxin antibodies revealed the intracellular cytoplasmic localization of ovatoxins, suggesting their cross-reactivity with these antibodies. Since harmful dinoflagellates do not always produce toxins, the immunocytochemical localization of ovatoxins, although qualitative, can provide an early warning for toxic Ostreopsis cells before their massive diffusion and/or concentration in seafood. 相似文献
32.
Giovanni Zemella Davide De March Matteo Borrotti Irene Poli 《Energy and Buildings》2011,43(12):3297-3302
Buildings are required to be more and more energy efficient, in order to comply with restrictive requirements of building regulations and energy certifications. Optimisation algorithms have shown to be effective in identifying good solutions for the design of efficient building services. In this article Evolutionary Neural Network Design (ENN-Design) has been adopted to drive the design of a typical façade module for an office building. This application is significant, since façades play a major role in the definition of the energy performance of buildings. Both single-objective and multi-objective optimisations have been carried out. The aim of the article is to introduce an innovative approach for improving the performance of building envelopes by means of a reasonable amount of calculation time. 相似文献
33.
Fichorova RN Richardson-Harman N Alfano M Belec L Carbonneil C Chen S Cosentino L Curtis K Dezzutti CS Donoval B Doncel GF Donaghay M Grivel JC Guzman E Hayes M Herold B Hillier S Lackman-Smith C Landay A Margolis L Mayer KH Pasicznyk JM Pallansch-Cokonis M Poli G Reichelderfer P Roberts P Rodriguez I Saidi H Sassi RR Shattock R Cummins JE 《Analytical chemistry》2008,80(12):4741-4751
The increase of proinflammatory cytokines in vaginal secretions may serve as a surrogate marker of unwanted inflammatory reaction to microbicide products topically applied for the prevention of sexually transmitted diseases, including HIV-1. Interleukin (IL)-1beta and IL-6 have been proposed as indicators of inflammation and increased risk of HIV-1 transmission; however, the lack of information regarding detection platforms optimal for vaginal fluids and interlaboratory variation limit their use for microbicide evaluation and other clinical applications. This study examines fluid matrix variants relevant to vaginal sampling techniques and proposes a model for interlaboratory comparisons across current cytokine detection technologies. IL-1beta and IL-6 standards were measured by 12 laboratories in four countries, using 14 immunoassays and four detection platforms based on absorbance, chemiluminescence, electrochemiluminescence, and fluorescence. International reference preparations of cytokines with defined biological activity were spiked into (1) a defined medium simulating the composition of human vaginal fluid at pH 4.5 and 7.2, (2) physiologic salt solutions (phosphate-buffered saline and saline) commonly used for vaginal lavage sampling in clinical studies of cytokines, and (3) human blood serum. Assays were assessed for reproducibility, linearity, accuracy, and significantly detectable fold difference in cytokine level. Factors with significant impact on cytokine recovery were determined by Kruskal-Wallis analysis of variance with Dunn's multiple comparison test and multiple regression models. All assays showed acceptable intra-assay reproducibility; however, most were associated with significant interlaboratory variation. The smallest reliably detectable cytokine differences ( P < 0.05) derived from pooled interlaboratory data varied from 1.5- to 26-fold depending on assay, cytokine, and matrix type. IL-6 but not IL-1beta determinations were lower in both saline and phosphate-buffered saline as compared to vaginal fluid matrix, with no significant effect of pH. The (electro)chemiluminescence-based assays were most discriminative and consistently detected <2-fold differences within each matrix type. The Luminex-based assays were less discriminative with lower reproducibility between laboratories. These results suggest the need for uniform vaginal sampling techniques and a better understanding of immunoassay platform differences and cross-validation before the biological significance of cytokine variations can be validated in clinical trials. This investigation provides the first standardized analytic approach for assessing differences in mucosal cytokine levels and may improve strategies for monitoring immune responses at the vaginal mucosal interface. 相似文献
34.
A Poli F Abramo D Matteucci F Baldinotti M Pistello S Lombardi P Barsotti M Bendinelli 《Canadian Metallurgical Quarterly》1995,46(1-2):13-20
In this work we analyze the following biomaterial: biomaterials used in this study are: reabsorbable Dac Blu, non reabsorbable Dac Blu, non reabsorbable atomized Dac Blu, non reabsorbable thin Dac Blu, reabsorbable Biocoral 450, Calcitite 2040-12, Orthogel, Apagen, BTF 65, Calcitite 4060-2, Osprogel, Bio-Oss, Biostite, Osprovit, Merck Hydroxiapatite. The quantitative XRF analysis was performed by a Philips PW 1480 with Rh tube. This research, besides underlining the possibility of applying the XRF method to the analysis of biomaterials. This study, shows the facility and the rapidity in the preparation of samples and standards in the form of tablets to undergo the analysis: furthermore the study shows the possibility of verify the analysis on the same sample in the future, because the tablet if well conserved, does not deteriorate. We can also verify a good analytic accuracy both for the principal elements (Ca, P) and for trace elements. The analyses show a moderate variability in the Ca/P ratio in the hydroxylapatites, and a greater variability in the secondary and trace elements. 相似文献
35.
Tin-rich organ pipes are often affected by localised deterioration in the form of grey pustules, pinholes, cracks and exfoliations
at the surface. Two main types of decay of tin-base materials that might have a similar appearance, i.e. the surface of the
object covered with dark grey pustules, are known. The first is the allotropic transformation of white metallic tin into grey
tin, the so-called “tin-pest”. The second form of decay is due to corrosion in the form of localised oxidation of tin. The
identification of the causes of deterioration is of main concern because, whereas oxidised material can be treated, an object
that suffers “tin pest” cannot be reconstituted. In the present paper the results of investigations on ancient tin-rich organ
pipes affected by localised degradation are presented. The study of the composition and the microstructure of the pipes has
been coupled with the results of analyses on the corrosion products. It was shown that oxidation clearly has a significant
role in the deterioration of tin pipes, but it was not possible to establish if the allotropic transformation took place or
not, because of the low probability of detecting the residual grey tin. 相似文献
36.
37.
VM Abascal MG Larson JC Evans AT Blohm K Poli D Levy 《Canadian Metallurgical Quarterly》1998,158(17):1882-1886
BACKGROUND: Several recent studies have suggested that calcium antagonist drugs, which are widely used for the treatment of hypertension, are associated with increased risk of cardiovascular disease. These studies have cast doubts on the long-term safety of calcium antagonists. OBJECTIVE: To examine the association of calcium antagonist use with mortality in subjects with hypertension followed up in the Framingham Heart Study. SUBJECTS AND METHODS: We stratified 3539 subjects (mean+/-SD age, 64+/-13 years) from the Framingham Heart Study who had hypertension at routine clinic examinations, according to the use of calcium antagonists and presence of coronary heart disease at the baseline examination. At each follow-up examination (every 2-4 years), subjects were reclassified with regard to the use of calcium antagonists. The end point of the study was all-cause mortality. Hazard ratios and 95% confidence intervals associated with the use of calcium antagonists were obtained using Cox proportional hazards regression models. RESULTS: There were 970 deaths during follow-up. Hazard ratios for mortality associated with the use of calcium antagonists were 0.93 (95% confidence interval, 0.72-1.21; P=.59) for subjects with hypertension without coronary heart disease, and 0.92 (95% confidence interval, 0.69-1.24; P=.58) for those with coronary heart disease at baseline. All models were adjusted for age, sex, current smoking, systolic and diastolic blood pressure, use of beta-blockers, and use of other antihypertensive medications. CONCLUSIONS: In this cohort of 3539 subjects with hypertension there were no differences in mortality among subjects with hypertension using a calcium antagonist compared with those who were not. Results were similar among subjects with hypertension with and without coronary heart disease. The results of ongoing long-term, randomized clinical trials will provide more definitive data on the safety of calcium antagonists. 相似文献
38.
39.
40.
G Bedogni S Severi AM Manzieri O Trunfio M Poli N Battistini 《Canadian Metallurgical Quarterly》1998,49(5-6):619-620
Validation studies of bioelectric impedance analysis (BIA) were performed in children with obesity, Duchenne muscle dystrophy and juvenile rheumatoid arthritis. BIA allowed an accurate assessment of total body water in all groups (CV from 4.1 to 5.1%). However, the prediction of extracellular water by BIA was not always satisfactory (CV from 8.5 to 12.5%), being better in the groups of children with the lowest variability in body water distribution. 相似文献