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Heavy metals in normal mucosa and nasal polyp tissues from Tunisian patients Texto completo
2015
Khlifi, Rim | Olmedo, Pablo | Gil, Fernando | Chakroun, Amine | Hammami, Boutheina | Hamza-Chaffai, Amel
Despite growing evidence that bacteria, fungi, allergens, and superantigens play a prominent role in the pathophysiology of nasal polyps (NP), the exact cause of polyposis is still unknown. The etiology of NP is considered multifactorial. Until now, there is no information on the presence of heavy metals, such as cadmium (Cd), chromium (Cr), nickel (Ni), and arsenic (As) or of their role, in the pathogenesis of NP disease. In this study, concentrations of these four metals in tissue of NP were determined using Atomic Absorption Spectrometry. The Ni, Cr, and As levels in NP tissues were 2.1-, 3.2-, and 8.0-fold higher than those of normal mucosa (p < 0.05), respectively. A strong effect of cumulative smoking as expressed in the number of pack per year (PY), Ni, As, and Cd levels in NP tissue samples of patients ever-smokers (1–20 and >20 PY) are significantly higher than those of non-smokers (p = 0.006, 0.002, and < 0.001, respectively). The highest As concentrations among patients lived at polluted areas (1–25 and > 25 years) were observed in both nasal mucosa and NP tissues. The Ni and As in both nasal mucosa and NP tissues of patients occupationally exposed were significantly higher than non-exposed group. Cr and As levels were found to be associated with NP stage classification (p < 0.05). This is the first report to describe an association between concentrations of metals (Cr, As, and Ni) in human NP tissues and the risk of NP disease. Tissue metal levels have increased due to smoking, environmental, and occupational exposure. Therefore, heavy metal exposure may increase the risk of NP in the Tunisian population. The considerable risk in the category of highest cumulative exposure argues for an association between heavy metals exposure and nasal polyposis risk. Future investigations with larger samples should better elucidate this association.
Mostrar más [+] Menos [-]Variation in tolerance to common marine pollutants among different populations in two species of the marine copepod Tigriopus Texto completo
2015
Sun, Patrick Y. | Foley, Helen B. | Bao, Vivien W. W. | Leung, Kenneth M. Y. | Edmands, Suzanne
Geographical variation in chemical tolerance within a species can significantly influence results of whole animal bioassays, yet a literature survey showed that the majority of articles using bioassays did not provide detail on the original field collection site of their test specimens confounding the ability for accurate replication and comparison of results. Biological variation as a result of population-specific tolerance, if not addressed, can be misinterpreted as experimental error. Our studies of two marine copepod species, Tigriopus japonicus and Tigriopus californicus, found significant intra- and inter-specific variation in tolerance to copper and tributyltin. Because both species tolerate copper concentrations orders of magnitude higher than those found in coastal waters, difference in copper tolerance may be a by-product of adaptation to other stressors such as high temperature. Controlling for inter-population tolerance variation will greatly strengthen the application of bioassays in chemical toxicity tests.
Mostrar más [+] Menos [-]Changes in the abundance of sugars and sugar-like compounds in tall fescue (Festuca arundinacea) due to growth in naphthalene-treated sand Texto completo
2015
Balasubramaniyam, Anuluxshy | Harvey, Patricia J
The hydrophilic metabolome of tall fescue (Festuca arundinacea) adapted to grow in naphthalene-treated sand (0.8 g kg⁻¹sand dw) was analysed using gas chromatography-mass spectrometry, and peaks corresponding to the more abundant compounds were tentatively identified from analysis of their mass spectral features and reference to the NIST Mass Spectral Database. Particular attention was paid to sugars as they are known to play important roles as stress regulators in plants. The results showed that the abundance of sugars was greater in the roots but lesser in the shoots of treated plants when compared to their control counterparts. The results for indole acetic acid (IAA) were notable: IAA was prominently less in the treated roots compared to shoots, and in treated shoots, IAA was particularly subdued compared to untreated shoots consistent with IAA degradation in treated plant tissues. The differences in the molecular phenotype between control and treated plants were expressed in root structural differences. The treated roots were modified to have greater suberisation, enhanced thickening in the endodermis and distortions in the cortical zone as demonstrated through scanning electron and epi-fluorescence microscopy.
Mostrar más [+] Menos [-]Neighborhood epidemiological monitoring and adult mental health: European Quality of Life Survey, 2007–2012 Texto completo
2015
Shiue, Ivy
Little is monitored on perceived neighborhood noise, quality of drinking water, air quality, rubbish, traffic, etc. at a continental scale. This study was aimed to examine the relationships of such neighborhood risks and mental health in adults and the very old in an international and population-based setting across Europe. Data were retrieved from the European Quality of Life Survey, 2007–2012 including demographics, living conditions, income and financial situation, housing and local environment, family, work, health, social participation and quality of social services. Adults aged 18 and above were included for statistical analysis (n = 79,270). Analysis included chi-square test, t test and logistic regression modeling. People who lived in town or city tended to indicate certain major problems for them such as noise (odds ratio (OR) 2.34, 95 % confidence interval (CI) 2.17–2.53, P < 0.001), air quality (OR 2.76, 95 % CI 2.54–3.00, P < 0.001), low quality of drinking water (OR 1.33, 95 % CI 1.23–1.43, P < 0.001), crime and/or violence (OR 2.92, 95 % CI 2.68–3.19, P < 0.001), rubbish (OR 3.68, 95 % CI 3.41–3.97, P < 0.001) and traffic congestion (OR 2.64, 95 % CI 2.45–2.85, P < 0.001). People who reported major problems on noise (OR 2.19, 95 % CI 1.96–2.45, P < 0.001), air quality (OR 2.11, 95 % CI 1.87–2.37, P < 0.001), low quality of drinking water (OR 2.40, 95 % CI 2.14–2.68, P < 0.001), crime and/or violence (OR 2.13, 95 % CI 1.88–2.41, P < 0.001), rubbish (OR 1.98, 95 % CI 1.77–2.11, P < 0.001) and traffic congestion (OR 1.50, 95 % CI 1.34–1.68, P < 0.001) were also classified as having depression. Perceived neighborhood conditions were associated with adult mental health across Europe. Future neighborhood monitoring research moving from the etiological to neighborhood management would be suggested.
Mostrar más [+] Menos [-]Distinguishing anthropogenic and natural sources of trace elements in soils undergoing recent 10-year rapid urbanization: a case of Donggang, Eastern China Texto completo
2015
Lv, Jianshu | Liu, Yang | Zhang, Zulu | Zhou, Rujia | Zhu, Yuchi
A total of 59 samples consisting of 45 topsoils samples and 14 subsoils samples were collected from urban soils of Donggang and were analyzed for soil properties and 12 trace elements. The mean contents of As, Cd, Co, Cr, Cu, Hg, Mn, Ni, Pb, Se, V, and Zn in topsoils were 5.76, 0.20, 9.88, 44.82, 17.69, 0.05, 578.96, 19.98, 28.38, 0.21, 58.88, and 58.32 mg kg⁻¹, respectively. The mean enrichment factor results suggested that Hg, Cd, Pb, Cu, Se, and Zn were enriched in topsoils compared with subsoils. Spatial distribution maps of trace elements indicated that Hg, Cd, Pb, Cu, Se, and Zn had similar patterns, with the highest values in the industrial region. There were no significant associations displayed between spatial distributions of As, Co, Cr, Mn, Ni, and V and the industrial region. Through correlation analysis, stepwise regression analysis, and redundancy analysis, three main sources of 12 trace elements were identified. Cd, Hg, and Se originated from industrial emissions and coal combustion, and As, Co, Cr, Mn, Ni, and V had a lithogenic origin. The combination of human activities and natural sources contributed to the contents of Cu, Pb, and Zn, and the human activities included industrial and traffic emissions.
Mostrar más [+] Menos [-]Competitive sorption and desorption of trace elements by Tunisian Aridisols Calcorthids Texto completo
2015
Sahraoui, Hamdi | Andrade, María Luisa | Hachicha, Mohamed | Vega, Flora Alonso
The sorption and retention processes play an important role in determining the bioavaibility and fate of trace elements in soils. Sorption and desorption of Pb²⁺, Zn²⁺, Ni²⁺, Cu²⁺, and Co²⁺ in three Tunisian Aridisols Calcorthids (AR1, AR2, and AR3) were studied using batch experiments. Sorption and retention capacities were determined by means of K ᵣ parameter and they were related to soil properties. The results showed that in all studied soils, K ᵣ values for Pb²⁺ and Cu²⁺ were higher than those of Zn²⁺, Ni²⁺, and Co²⁺ indicating that soils have higher affinity for the first ones. The high sorption and retention capacity of the three studied soils is ascribed to their alkaline pH and their high carbonates contents favoring the precipitation of these elements. Moreover, bivariate correlation analysis showed that sorption and retention of the studied cations was also strongly correlated with clay fraction and Fe oxides contents. All soils show high sorption irreversibility of Pb²⁺, Zn²⁺, Ni²⁺, Cu²⁺, and Co²⁺. The soils with highest sorption capacity show also the highest irreversibility.
Mostrar más [+] Menos [-]Air quality modeling in the Oviedo urban area (NW Spain) by using multivariate adaptive regression splines Texto completo
2015
Nieto, P. J García | Antón, J. C Álvarez | Vilán, J. A Vilán | García-Gonzalo, E.
The aim of this research work is to build a regression model of air quality by using the multivariate adaptive regression splines (MARS) technique in the Oviedo urban area (northern Spain) at a local scale. To accomplish the objective of this study, the experimental data set made up of nitrogen oxides (NO ₓ), carbon monoxide (CO), sulfur dioxide (SO₂), ozone (O₃), and dust (PM₁₀) was collected over 3 years (2006–2008). The US National Ambient Air Quality Standards (NAAQS) establishes the limit values of the main pollutants in the atmosphere in order to ensure the health of healthy people. Firstly, this MARS regression model captures the main perception of statistical learning theory in order to obtain a good prediction of the dependence among the main pollutants in the Oviedo urban area. Secondly, the main advantages of MARS are its capacity to produce simple, easy-to-interpret models, its ability to estimate the contributions of the input variables, and its computational efficiency. Finally, on the basis of these numerical calculations, using the MARS technique, conclusions of this research work are exposed.
Mostrar más [+] Menos [-]Formaldehyde exposure in gross anatomy laboratory of Suranaree University of Technology: a comparison of area and personal sampling Texto completo
2015
Saowakon, Naruwan | Ngernsoungnern, Piyada | Watcharavitoon, Pornpun | Ngernsoungnern, Apichart | Kosanlavit, Rachain
Cadavers are usually preserved by embalming solution which is composed of formaldehyde (FA), phenol, and glycerol. Therefore, medical students and instructors have a higher risk of exposure to FA inhalation from cadavers during dissection. Therefore, the objective of this study was to evaluate the FA exposure in indoor air and breathing zone of medical students and instructors during dissection classes in order to investigate the relationship between them. The indoor air and personal air samples in breathing zone were collected three times during anatomy dissection classes (in January, August, and October of 2014) with sorbent tubes, which were analyzed by high-performance liquid chromatography (HPLC). The air cleaner machines were determined by weight measurement. Pulmonary function tests and irritation effects were also investigated. The mean of FA concentrations ranged from 0.117 to 0.415 ppm in the indoor air and from 0.126 to 1.176 ppm in the breathing zone of students and instructors. All the personal exposure data obtained exceeded the threshold limit of NIOSH and WHO agencies. The air cleaner machines were not significant difference. The pulmonary function of instructors showed a decrease during attention of classes and statistically significant decreasing in the instructors more than those of the students. Clinical symptoms that were observed in nose and eyes were irritations with general fatigue. We suggested that the modified exhaust ventilation and a locally ventilated dissection work table were considered for reducing FA levels in the gross anatomy dissection room.
Mostrar más [+] Menos [-]Antibiotics and sweeteners in the aquatic environment: biodegradability, formation of phototransformation products, and in vitro toxicity Texto completo
2015
Bergheim, Marlies | Gminski, Richard | Spangenberg, Bernd | Debiak, Malgorzata | Bürkle, Alexander | Mersch-Sundermann, Volker | Kümmerer, Klaus | Gieré, Reto
In the present study, in vitro toxicity as well as biopersistence and photopersistence of four artificial sweeteners (acesulfame, cyclamate, saccharine, and sucralose) and five antibiotics (levofloxacin, lincomycin, linezolid, marbofloxacin, and sarafloxacin) and of their phototransformation products (PTPs) were investigated. Furthermore, antibiotic activity was evaluated after UV irradiation and after exposure to inocula of a sewage treatment plant. The study reveals that most of the tested compounds and their PTPs were neither readily nor inherently biodegradable in the Organisation for Economic Co-operation and Development (OECD)-biodegradability tests. The study further demonstrates that PTPs are formed upon irradiation with an Hg lamp (UV light) and, to a lesser extent, upon irradiation with a Xe lamp (mimics sunlight). Comparing the nonirradiated with the corresponding irradiated solutions, a higher chronic toxicity against bacteria was found for the irradiated solutions of linezolid. Neither cytotoxicity nor genotoxicity was found in human cervical (HeLa) and liver (Hep-G2) cells for any of the investigated compounds or their PTPs. Antimicrobial activity of the tested fluoroquinolones was reduced after UV treatment, but it was not reduced after a 28-day exposure to inocula of a sewage treatment plant. This comparative study shows that PTPs can be formed as a result of UV treatment. The study further demonstrated that UV irradiation can be effective in reducing the antimicrobial activity of antibiotics, and consequently may help to reduce antimicrobial resistance in wastewaters. Nevertheless, the study also highlights that some PTPs may exhibit a higher ecotoxicity than the respective parent compounds. Consequently, UV treatment does not transform all micropollutants into harmless compounds and may not be a large-scale effluent treatment option.
Mostrar más [+] Menos [-]Phytosynthesis of silver nanoparticles using the leaves extract of Ficus talboti king and evaluation of antioxidant and antibacterial activities Texto completo
2015
Arunachalam, K. | Shanmuganathan, B. | Sreeja, P. S. | Parimelazhagan, T.
The present study, the synthesis of silver nanoparticles (AgNPs) at 90 °C temperature using an aqueous extract from Ficus talboti leaf and the antioxidant and antibacterial activities of the AgNPs obtained. The devised method is simple and cost-effective, and it produces spherical AgNPs of size 11.9 ± 2.3 nm. The synthesized AgNPs was characterized as UV–vis spectrum and obtain a peak at 438 nm. The phytochemical study result shows that the secondary metabolites such as alkaloids, saponins, phenolic compounds, tannin, flavonoids, phytosterol, and glycosides may be responsible for reducing as well as capping silver ions into AgNPs. Transmission electron microscopic (TEM) studies of the particles revealed a dominance of spherical particle AgNPs. The face centered cubic structure of the AgNPs was confirmed by X-ray diffraction (XRD) peaks at 111°, 200°, 220°, and 311°; SAED patterns confirms the plane of silver nanoparticle planes with clear circular spots on the selected area electron diffraction (SAED). Elemental analysis was done by energy dispersive X-ray analysis (EDX). In addition, this study evaluated the in vitro antioxidant and antibacterial properties of the biosynthesized AgNPs that were found to be significant.
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