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1.
Environ Pollut ; 298: 118768, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34990737

RESUMEN

The present study highlights the importance of examining the contribution of Saharan dust (SD) sources not only in terms of overall mass contribution but also in terms of composition, size distribution and inhaled dose. The effect of SD intrusions on PM and the respective major and trace metals mass concentrations and size distributions was investigated in a suburban site in Athens, Greece. SD events were associated, on average, with lower boundary layer heights (BLH) compared to the non-Sahara (nSD) dust days. During SD events, PM1-10 concentrations showed an increasing trend with increasing atmospheric BLH, in contrary to the fine PM (PM1). Generally, increased PM1 and CO (i.e. anthropogenic origin) levels were observed for BLH lower than around 500 m. The average contribution of SD to PM10 and PM2.5 mass concentration was roughly equal to 30.9% and 19.4%, respectively. The mass size distributions of PM and specific major and trace elements (Na, Al, Si, S, Cl, K, Ca, Fe, and Zn) displayed a somewhat different behavior with respect to the mass origin (Algeria-Tunisia vs Libya-Egypt), affecting in turn the regional deposition of inhaled aerosol in the human respiratory tract (HRT). The average PM deposited mass in the upper and lower HRT was 80.1% (Head) and 26.9% (Lung; Tracheobronchial and Pulmonary region) higher for SD days than for nSD days. Higher doses were estimated in the upper and lower HRT for the majority of the elements, when SD intrusions occurred, supporting the increasingly growing interest in exploring the health effects of SD. Only the mass deposition for S, and Na in the lower HRT and Zn in the upper HRT was higher in the case of nSD.


Asunto(s)
Contaminantes Atmosféricos , Material Particulado , Contaminantes Atmosféricos/análisis , Brotes de Enfermedades , Polvo/análisis , Monitoreo del Ambiente , Humanos , Tamaño de la Partícula , Material Particulado/análisis
2.
Sci Total Environ ; 807(Pt 3): 151021, 2022 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-34662608

RESUMEN

Particulate matter (PM) pollution is one of the major environmental concerns due to its harmful effects on human health. As children are particularly vulnerable to particle exposure, this study integrates the concentration of PM chemical compounds measured in the micro-environments (MEs) where children spend most of their time to assess the daily exposure and inhaled dose. PM samples were analysed for organic and elemental carbon and for major and trace elements. Results showed that the MEs that contribute most to the children's daily exposure (80%) and inhaled dose (65%) were homes and schools. Results indicated that the high contribution of particulate organic matter (POM) indoors indicate high contributions of indoor sources to the organic fraction of the particles. The highest concentrations of PM chemical compounds and the highest Indoor/Outdoor ratios were measured in schools, where the contribution of mineral elements stands out due to the resuspension of dust caused by the students and to the chalk used in blackboards. The contribution of the outdoor particles to inhaled dose (24%) was higher than to the exposure (12%), due to the highest inhalation rates associated with the activities performed outdoor. This study indicates the importance of indoor air quality for the children's exposure and health.


Asunto(s)
Oligoelementos , Niño , Humanos , Material Particulado , Instituciones Académicas
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 1431-1434, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34891554

RESUMEN

High Intensity Focused Ultrasound (HIFU) surgery is a promising technology for the treatment of several pathologies, including cancer. Testing is a fundamental step for verifying treatment efficacy and safety. Ex-vivo tissues represent the most common solution for replicating the properties of human tissues in the HIFU operative scenario. However, they constitute an avoidable waste of resources. Thus, tissue mimicking phantoms have been investigated as a more sustainable and reliable alternative. In this scenario, we proposed a reusable silicone-based thermochromic phantom. It is cost-effective and can be rapidly fabricated. The acoustic, mechanical, and thermal characterization of the phantom are reported. The phantom usability was evaluated with a HIFU robotic platform. 18 different working conditions were tested by varying both sonication power and duration. Temperature and simulated lesions' size were quantified for all testing conditions. An accordance between temperature and lesion dimension trend over time was found. The proposed phantom results a valid alternative to ex-vivo tissues, especially in the early stages of developing novel HIFU treatment paradigms.


Asunto(s)
Ultrasonido Enfocado de Alta Intensidad de Ablación , Humanos , Fantasmas de Imagen , Sonicación , Tecnología , Temperatura
4.
Environ Res ; 192: 110257, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33031811

RESUMEN

The study aims to assess the differences between the chemical profiles of the major anthropogenic and natural PM sources in two areas with different levels of urbanization and traffic density within the same urban agglomeration. A traffic site and an urban background site in the Athens Metropolitan Area have been selected for this comparison. For both sites, eight sources were identified, with seven of them being common for the two sites (Mineral Dust, non-Exhaust Emissions, Exhaust Emissions, Heavy Oil Combustion, Sulfates & Organics, Sea Salt and Biomass Burning) and one, site-specific (Nitrates for the traffic site and Aged Sea Salt for the urban background site). The similarity between the source profiles was quantified using two statistical analysis tools, Pearson correlation (PC) and Standardized Identity Distance (SID). According to Pearson coefficients five out of the eight source profiles present high (PC > 0.8) correlation (Mineral Dust, Biomass Burning, Sea Salt, Sulfates and Heavy Oil Combustion), one presented moderate (0.8 > PC > 0.6) correlation (Exhaust) and two low/no (PC < 0.6) correlation (non-Exhaust, Nitrates/Aged Sea Salt). The source profiles that appear to be more correlated are those of sources that are not expected to have high spatial variability because there are either natural/secondary and thus have a regional character or are emitted outside the urban agglomeration and are transported to both sites. According to SID four out of the eight sources have high statistical correlation (SID < 1) in the two sites (Mineral Dust, Sea salt, Sulfates, Heavy Oil Combustion). Biomass Burning was found to be the source that yielded different results from the two methodologies. The careful examination of the source profile of that source revealed the reason for this discrepancy. SID takes all the species of the profile equally into account, while PC might be disproportionally affected by a few numbers of species with very high concentrations. It is suggested, based on the findings of this work, that the combined use of both tools can lead the users to a thorough evaluation of the similarity of source profiles. This work is, to the best of our knowledge, the first time a study is focused on the quantitative comparison of the source profiles for sites inside the same urban agglomeration using statistical indicators.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Polvo/análisis , Monitoreo del Ambiente , Nitratos , Material Particulado/análisis , Emisiones de Vehículos/análisis
5.
Arch Environ Contam Toxicol ; 64(3): 347-56, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23223937

RESUMEN

The objective of this study was to identify and quantify the sources of fine particulate aliphatic and polycyclic aromatic hydrocarbons (PAHs) in an urban area in southeastern Europe. A total of 91 urban PM2.5 samples were analyzed by gas chromatography coupled with mass spectrometry for alkanes and PAHs. Exploratory statistical tools were applied to resolve a decreased number of components based on the variation of measurements. Molecular markers and diagnostic ratios were examined to assign retained components to specific sources. The contributions of the sources were estimated by multivariate linear regression. Sources of aliphatic and PAHs hydrocarbons included primary particles from traffic (3.9 ng/m(3) for alkanes and 240 pg/m(3) for PAHs), evaporative fugitive (4.0 ng/m(3) for alkanes and 93 pg/m(3) for PAHs), and unburnt fuels and oil residues (1.1 ng/m(3) for alkanes and 230 pg/m(3) for PAHs). For the first time, we quantified the contribution of environmental tobacco smoke (ETS), which accounted for 5.2 ng/m(3) of alkanes and 128 pg/m(3) of PAHs. The findings of this study underlined the persistence of ETS and possible exposures to significant quantities of tobacco residues outdoors. Tobacco smoke is known to induce adverse respiratory and cardiovascular illnesses and increased risk for cancer.


Asunto(s)
Alcanos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Contaminación por Humo de Tabaco/análisis , Grecia , Tamaño de la Partícula , Estaciones del Año , Urbanización
6.
J Environ Radioact ; 114: 100-4, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22197531

RESUMEN

As a result of the nuclear accident in Fukushima Dai-ichi power plant, which started on March 11, 2011, radioactive pollutants were transferred by air masses to various regions of the Northern hemisphere, including Europe. Very low concentrations of (131)I, (137)Cs and (134)Cs in airborne particulate matter were measured in Athens, Greece during the period of March 24 to April 28, 2011. The maximum air concentration of (131)I was measured on April 6, 2011 and equaled 490 ± 35 µBq m(-3). The maximum values of the two cesium isotopes were measured on the same day and equaled 180 ± 40 µBq m(-3) for (137)Cs and 160 ± 30 µBq m(-3) for (134)Cs. The average activity ratio of (131)I/(137)Cs in air was 3.0 ± 0.5, while the corresponding ratio of (137)Cs/(134)Cs equaled 1.1 ± 0.3. No artificial radionuclides could be detected in air after April 28, 2011. Traces of (131)I as a result of radioactive deposition were measured in grass, soil, sheep milk and meat. The total deposition of (131)I (dry + wet) was 34 ± 4 Bq m(-2), and of (137)Cs was less than 10 Bq m(-2). The maximum concentration of (131)I in grass was 2.1 ± 0.4 Bg kg(-1), while (134)Cs was not detected. The maximum concentrations of (131)I and (137)Cs in sheep milk were 1.7 ± 0.16 Bq kg(-1) and 0.6 ± 0.12 Bq kg(-1) respectively. Concentrations of (131)I up to 1.3 ± 0.2 Bq kg(-1) were measured in sheep meat. Traces of (131)I were found in a number of soil samples. The radiological impact of the Fukushima nuclear accident in Athens region was practically negligible, especially as compared to that of the Chernobyl accident and also to that of natural radioactivity.


Asunto(s)
Radioisótopos de Cesio , Contaminación Radiactiva de Alimentos/análisis , Accidente Nuclear de Fukushima , Radioisótopos de Yodo , Contaminantes Radiactivos/análisis , Animales , Accidente Nuclear de Chernóbil , Grecia , Japón , Carne/análisis , Leche/química , Poaceae/química , Monitoreo de Radiación , Ovinos , Suelo/análisis , Ucrania
7.
Br J Dermatol ; 164(3): 610-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21073448

RESUMEN

BACKGROUND: CEDNIK (cerebral dysgenesis, neuropathy, ichthyosis and keratoderma) syndrome is a rare genodermatosis which was shown 5 years ago in one family to be associated with a loss-of-function mutation in SNAP29, encoding a member of the SNARE family of proteins. Decrease in SNAP29 expression was found to result in abnormal lamellar granule maturation leading to aberrant epidermal differentiation and ichthyosis. OBJECTIVES: To delineate the molecular consequences of disease-causing mutations in SNAP29. METHODS: We used direct sequencing, in vitro mutagenesis and three-dimensional organotypic cell cultures. RESULTS: We identified a novel homozygous insertion in SNAP29 (c.486insA) in two sibs presenting with ichthyosis and dysgenesis of the corpus callosum. In vitro transfection experiments indicated that this mutation results in SNAP29 loss-of-function. Further substantiating this notion, we could replicate histological features typical for CEDNIK syndrome in three-dimensional primary human keratinocyte organotypic cell cultures downregulated for SNAP29. CONCLUSIONS: The identification of a second mutation in SNAP29 in the present study definitely establishes a causal relationship between defective function of SNAP29 and the pleiotropic manifestations of CEDNIK syndrome. Our present and previous data position SNAP29 as an essential component of the epidermal differentiation machinery.


Asunto(s)
Mutación/genética , Proteínas Qb-SNARE/genética , Proteínas Qc-SNARE/genética , Western Blotting , Células Cultivadas , Femenino , Humanos , Lactante , Queratodermia Palmoplantar/genética , Queratodermia Palmoplantar/patología , Masculino , Síndromes Neurocutáneos/genética , Síndromes Neurocutáneos/patología , Proteínas Qb-SNARE/metabolismo , Proteínas Qc-SNARE/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Secuencia de ADN
8.
Attach Hum Dev ; 2(2): 149-69, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11707908

RESUMEN

Dyadic emotional availability and infant-mother attachment relationship were examined in 687 Israeli dyads. Concurrent assessments used the Strange Situation procedure (Ainsworth, Blehar, Waters, & Wall, 1978) for evaluating infants' attachment relationship, and the Emotional Availability Scales (Biringen, Robinson, & Emde, 1993) for evaluating the quality of mother-child interaction. It was found that higher scores on the Emotional Availability Scales were associated with infant attachment security. In addition, it was found that the Emotional Availability Scales discriminated between insecure-ambivalent and secure attachment classification, but were not informative about unique characteristics of emotional availability in dyads with avoidant and disorganized infants. Our findings contribute to the cross-cultural validation of Emotional Availability Scales against infants' attachment security.


Asunto(s)
Emociones , Conducta Materna , Relaciones Madre-Hijo , Apego a Objetos , Femenino , Hostilidad , Humanos , Lactante , Israel , Masculino , Determinación de la Personalidad , Desarrollo de la Personalidad , Medio Social
9.
Artif Intell Med ; 10(1): 25-40, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9177814

RESUMEN

This paper describes a computational model developed for the diagnosis of multiple defects. If multiple defects interact, meaning that the cues observable for multiple defects are not a sum of the cues observable for the component defects, diagnosis is particularly difficult. We developed a description and classification of the ways cues change when defects interact. A computational model (named Fallot) was implemented and a knowledge-base was constructed for the diagnosis of congenital heart defects. On each case, Fallot performs recognition-based reasoning followed by solution construction and evaluation with the cue combination methods. Fallot was tested on cases from hospital files and correctly diagnoses cases with multiple interacting defects for which conventional methods are not applicable or fail.


Asunto(s)
Anomalías Múltiples/diagnóstico , Inteligencia Artificial , Diagnóstico por Computador , Cardiopatías Congénitas/diagnóstico , Niño , Humanos , Pediatría
10.
Artículo en Inglés | MEDLINE | ID: mdl-18255901

RESUMEN

Complex robot tasks are usually described as high level goals, with no details on how to achieve them. However, details must be provided to generate primitive commands to control a real robot. A sensor explication concept that makes details explicit from general commands is presented. We show how the transformation from high-level goals to primitive commands can be performed at execution time and we propose an architecture based on reconfigurable objects that contain domain knowledge and knowledge about the sensors and actuators available. Our approach is based on two premises: 1) plan execution is an information gathering process where determining what information is relevant is a great part of the process; and 2) plan execution requires that many details are made explicit. We show how our approach is used in solving the task of moving a robot to and through an unknown, and possibly narrow, doorway; where sonic range data is used to find the doorway, walls, and obstacles. We illustrate the difficulty of such a task using data from a large number of experiments we conducted with a real mobile robot. The laboratory results illustrate how the proper application of knowledge in the integration and utilization of sensors and actuators increases the robustness of plan execution.

13.
Minerva Med ; 77(3-4): 93-104, 1986 Jan 28.
Artículo en Italiano | MEDLINE | ID: mdl-3511410

RESUMEN

The analgesic efficacy and tolerability of a morphine agonist-antagonist buprenorphine are evaluated. The drug is compared to pentazocin. For this purpose, the drugs were randomly administered to 42 patients suffering from pain caused by advanced cancer. Buprenorphine demonstrated a significantly higher analgesic effect than pentazocin and was better tolerated.


Asunto(s)
Buprenorfina/uso terapéutico , Morfinanos/uso terapéutico , Neoplasias/tratamiento farmacológico , Dolor Intratable/tratamiento farmacológico , Buprenorfina/efectos adversos , Ensayos Clínicos como Asunto , Evaluación de Medicamentos , Femenino , Humanos , Masculino , Pentazocina/efectos adversos , Pentazocina/uso terapéutico
20.
Int J Clin Pharmacol Ther Toxicol ; 23(7): 373-5, 1985 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-4030167

RESUMEN

Forty-two patients undergoing cryosurgery for skin diseases were treated by means of the simultaneous application of three creams, the respective bases of which were beclomethasone dipropionate, sodium fusidate and ketoconazole. The treatment produced excellent results, preventing bacterial and/or mycotic superinfections and relieving the edema and erythema caused by the operation in 97.6% of cases. Local tolerance was optimal in all cases; no adverse reactions of any kind being reported.


Asunto(s)
Antiinfecciosos Locales/uso terapéutico , Antiinflamatorios/uso terapéutico , Antifúngicos/uso terapéutico , Criocirugía , Enfermedades de la Piel/cirugía , Adolescente , Adulto , Anciano , Beclometasona/uso terapéutico , Niño , Terapia Combinada , Combinación de Medicamentos , Eritema/tratamiento farmacológico , Femenino , Ácido Fusídico/uso terapéutico , Humanos , Cetoconazol/uso terapéutico , Masculino , Persona de Mediana Edad , Enfermedades de la Piel/tratamiento farmacológico
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