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1.
Braz J Med Biol Res ; 55: e12141, 2022.
Article in English | MEDLINE | ID: mdl-36350971

ABSTRACT

The aim of this study was to compare the frequency of dysplasia and human papillomavirus (HPV) infection in the anal canal of patients with Crohn's disease (CD) with a control group and assess whether there is a correlation between use of immunosuppressants and anal manifestation of CD. Patients with CD and control individuals were submitted to anal cytology and material collection for polymerase chain reaction (PCR). The cytology was classified as normal, atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL), or high-grade (HSIL). PCR was considered positive or negative according to virus presence or absence. A total of 117 patients were included (54 in the control group and 63 in the CD group, being 32 without and 31 with immunosuppressants). ASCUS and LSIL were found in 25.9 and 22.2% of control patients and 28.6 and 39.7% of CD patients. HPV was identified in 14.8% of the control group and 27% of the CD group. In CD patients, HPV was found in 37.5 and 16.1% of those without and with immunosuppressants, respectively. Patients with perianal involvement had 15.6% of PCR positivity. There was no statistical difference in dysplasia and infection by HPV between the groups. Use of immunosuppressants did not influence the result, but anal manifestation was inversely proportional to viral detection.


Subject(s)
Alphapapillomavirus , Anus Neoplasms , Atypical Squamous Cells of the Cervix , Crohn Disease , Papillomavirus Infections , Uterine Cervical Neoplasms , Female , Humans , Papillomaviridae/genetics , Papillomavirus Infections/diagnosis , Crohn Disease/complications , Anus Neoplasms/pathology , Immunosuppressive Agents/therapeutic use
2.
Braz. j. med. biol. res ; 55: e12141, 2022. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1403910

ABSTRACT

The aim of this study was to compare the frequency of dysplasia and human papillomavirus (HPV) infection in the anal canal of patients with Crohn's disease (CD) with a control group and assess whether there is a correlation between use of immunosuppressants and anal manifestation of CD. Patients with CD and control individuals were submitted to anal cytology and material collection for polymerase chain reaction (PCR). The cytology was classified as normal, atypical squamous cells of undetermined significance (ASCUS), low-grade squamous intraepithelial lesion (LSIL), or high-grade (HSIL). PCR was considered positive or negative according to virus presence or absence. A total of 117 patients were included (54 in the control group and 63 in the CD group, being 32 without and 31 with immunosuppressants). ASCUS and LSIL were found in 25.9 and 22.2% of control patients and 28.6 and 39.7% of CD patients. HPV was identified in 14.8% of the control group and 27% of the CD group. In CD patients, HPV was found in 37.5 and 16.1% of those without and with immunosuppressants, respectively. Patients with perianal involvement had 15.6% of PCR positivity. There was no statistical difference in dysplasia and infection by HPV between the groups. Use of immunosuppressants did not influence the result, but anal manifestation was inversely proportional to viral detection.

3.
J Hazard Mater ; 414: 125562, 2021 07 15.
Article in English | MEDLINE | ID: mdl-34030413

ABSTRACT

Pernicious effects of plastic particles, emergent contaminants worldwide, have been described in different species. In teleost species, alterations of immune function after exposure to nanoplastics (NPs) have been reported, but the interaction with cortisol - hypothalamic-pituitary-adrenal (HPI) axis has not yet been explored. Furthermore, the role of dissolved organic matter on the effects of NPs is poorly known. Thus, the aims of this research were to assess if polystyrene NPs (PSNPs) acted as a stressor on juvenile European seabass (Dicentrarchus labrax), interfering with the immune response, as well as to elucidate if humic acids (HA) modulated the potential effects of PSNPs. A short-term exposure to PSNPs and HA elicited an immuno-modulatory response, with an activation of steroidogenic stress-related pathways. An upregulation of anti-inflammatory cytokine (il10, tgfb) and stress-related (mc2r, gr1) transcripts were observed after exposure to HA and PSNPs both individually and in co-exposure. No notable alteration of inflammatory markers was consistently found, which may reflect a protective anti-inflammatory effect of HA in the presence of PSNPs. Nevertheless, there seems to be a more complex interaction between both components. Overall, data show that understanding the interaction of NPs with dissolved organic substances is key to deciphering their environmental risks.


Subject(s)
Bass , Animals , Humic Substances , Immunity , Microplastics , Polystyrenes
4.
Graefes Arch Clin Exp Ophthalmol ; 259(3): 759-768, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32945936

ABSTRACT

PURPOSE: To assess visual acuity in 5-year-old children with LEA chart and to estimate the frequency of reduced visual acuity in this age. METHOD: Study aimed at children attending the last year of preschool education in Public Kindergartens and Private Social Solidarity Institutions (IPSS) under the influence Regional Health Administration of the Médio Tejo, in Portugal. The 15-line LEA charts at 3 m were used and the presentation visual acuity was measured monocularly starting with the right eye. The ETDRS-fast methodology was used. RESULTS: A total of 3072 children participated, being 51% male and 54% from rural area. A rate of 13.7% children with a reduced level of visual acuity was found, that is, visual acuity worse or equal to 0.2 logMAR in at least one eye, or an interocular difference greater than two lines. CONCLUSION: This research shows that reduced VA frequency rate in children between 5 and 6 years old is high. The literature presents amblyopia (refractive and/or strabismic) and uncorrected refractive errors without amblyopia as the main cause of reduced VA in childhood, and these anomalies negatively affect child development, especially at the educational level. Reduced VA interferes with performance on a number of key tasks in the learning process. Thus, it is important to preserve the running program to identify these deficits and lead to their correction before the beginning of the school stage.


Subject(s)
Amblyopia , Refractive Errors , Visual Acuity , Amblyopia/physiopathology , Child , Child, Preschool , Female , Humans , Male , Portugal , Vision Tests
5.
Article in English | MEDLINE | ID: mdl-31815087

ABSTRACT

In this work, eco-friendly magnesium-silicide (Mg2Si) semiconducting (n-type) thermoelectric pastes for building components concerning energy-harvesting devices through 3D printing, spray and electrospinning were synthetized and tested for the first time. The Mg2Si fine powders were obtained through the combination of ball milling and thermal annealing under Ar atmosphere. While the latter process was crucial for obtaining the desired Mg2Si phase, the ball milling was indispensable for homogenizing and reducing the grain size of the powders. The synthetized Mg2Si powders exhibited a large Seebeck coefficient of ~ 487 µV/K and were blended with a polymeric solution in different mass ratios to adjust the paste viscosity to the different requirements of 3D printing, electrospinning and low-pressure spray. The materials produced in every single stage of the paste synthesis were characterized by a variety of techniques that unequivocally prove their viability for producing thermoelectric parts and components. These can certainly trigger further research and development in green thermoelectric generators (TEGs) capable of adopting any form or shape with enhanced thermoelectric properties. These green TEGs are meant to compete with common toxic materials such as Bi2Te3, PbTe and CoSb that have Seebeck coefficients in the range of ~ 290-700 µV/K, similar to that of the produced Mg2Si powders and lower than that of 3D printed bulk Mg2Si pieces, measured to be ~ 4866 µV/K. Also, their measured thermal conductivities proved to be significantly lower (~ 0.2 W/mK) than that reported for Mg2Si (≥ 4 W/mK). However, it is herein demonstrated that such thermoelectric properties are not stable over time. Pressureless sintering proved to be indispensable, but difficultly achievable by long thermal annealing (even above 32 h) in inert atmosphere at 400 °C, at least for bulk Mg2Si pieces constituted by a mean grain size of 2-3 µm. Hence, for overcoming this sintering challenge and become the silicide's extrusion viable in the production of bulk thermoelectric parts, alternative pressureless sintering methods will have to be further explored.

6.
Sci Total Environ ; 643: 775-784, 2018 Dec 01.
Article in English | MEDLINE | ID: mdl-29958167

ABSTRACT

Plastic pollution is a worldwide problem, highlighted by the fact that plastic materials degrade into nano-size particles (<100 nm), potentially becoming more bioavailable as well as a source of entry of other contaminants into organisms. The present study aimed to assess the effects of polystyrene nanoplastics (PS), individually or combined with carbamazepine (Cbz), on the Mediterranean mussel, Mytilus galloprovincialis. For this purpose, mussels were exposed for 96 h to a concentration range of PS (from 0.05 up to 50 mg L-1), to Cbz (6.3 µg L-1) alone and to the mixture of PS + Cbz (0.05 mg L-1+ 6.3 µg L-1). Molecular and biochemical biomarkers were assessed in the digestive glands, gills and haemolymph. The abundance of mRNA in the digestive glands and gills revealed significant alterations in the expression of genes associated with biotransformation, DNA repair, cell stress-response and innate immunity. Combined exposure of PS + Cbz induced significant downregulation in gene expression (e.g., hsp70) when compared to individual exposure. Total oxidant status increased in digestive glands after exposure to 0.5 mg L-1 PS. Moreover, increased total antioxidant capacity and esterase activity were observed for PS 50 mg L-1, in digestive glands and gills, respectively. The PS induced effects on neurotransmission, measured as inhibition of cholinesterase activity in haemolymph. Genotoxicity was found in haemocytes after exposure to PS, Cbz and their mixture. Moreover, lipid peroxidation was observed for 0.05 mg L-1 PS exposure, showing that nanoplastics can induce oxidative damage. The present study demonstrated that PS, even at low concentrations, led to alterations on the assessed mussels' endpoints.


Subject(s)
Carbamazepine/toxicity , Mytilus/physiology , Plastics/toxicity , Water Pollutants, Chemical/toxicity , Animals , Biomarkers , Gills , Oxidative Stress
7.
J Dent Res ; 95(12): 1394-1400, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27470069

ABSTRACT

This study was designed to develop and characterize a silica-coating method for crystalline nonsilicate ceramic nanoparticles (Al2O3, TiO2, and ZrO2). The hypothesis was that the coated nonsilicate nanoparticles would stably reinforce a polymeric matrix due to effective silanation. Silica coating was applied via a sol-gel method, with tetraethyl orthosilicate as a silica precursor, followed by heat treatment. The chemical and microstructural characteristics of the nanopowders were evaluated before and after silica coating through x-ray diffraction, BET (Brunauer-Emmett-Teller), energy-dispersive x-ray spectroscopy, field emission scanning electron microscopy, and transmission electron microscopy analyses. Coated and noncoated nanoparticles were silanated before preparation of hybrid composites, which contained glass microparticles in addition to the nanoparticles. The composites were mechanically tested in 4-point bending mode after aging (10,000 thermal cycles). Results of all chemical and microstructural analyses confirmed the successful obtaining of silica-coated nanoparticles. Two distinct aspects were observed depending on the type of nanoparticle tested: 1) formation of a silica shell on the surface of the particles and 2) nanoparticle clusters embedded into a silica matrix. The aged hybrid composites formulated with the coated nanoparticles showed improved flexural strength (10% to 30% higher) and work of fracture (35% to 40% higher) as compared with composites formulated with noncoated nanoparticles. The tested hypothesis was confirmed: silanated silica-coated nonsilicate nanoparticles yielded stable reinforcement of dimethacrylate polymeric matrix due to effective silanation. The silica-coating method presented here is a versatile and promising novel strategy for the use of crystalline nonsilicate ceramics as a reinforcing phase of polymeric composite biomaterials.


Subject(s)
Composite Resins/chemistry , Dental Materials/chemistry , Nanoparticles/chemistry , Silicon Dioxide/chemistry , Aluminum Oxide/chemistry , Computer-Aided Design , Dental Stress Analysis , Materials Testing , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission , Polymers/chemistry , Silanes/chemistry , Spectrometry, X-Ray Emission , Surface Properties , Tensile Strength , Titanium/chemistry , X-Ray Diffraction , Zirconium/chemistry
8.
Microb Cell ; 1(9): 289-302, 2014 Aug 09.
Article in English | MEDLINE | ID: mdl-28357255

ABSTRACT

Alterations in the intracellular levels of calcium are a common response to cell death stimuli in animals and fungi and, particularly, in the Neurospora crassa response to staurosporine. We highlight the importance of the extracellular availability of Ca2+ for this response. Limitation of the ion in the culture medium further sensitizes cells to the drug and results in increased accumulation of reactive oxygen species (ROS). Conversely, an approximately 30-fold excess of external Ca2+ leads to increased drug tolerance and lower ROS generation. In line with this, distinct staurosporine-induced cytosolic Ca2+ signaling profiles were observed in the absence or presence of excessive external Ca2+. High-throughput RNA sequencing revealed that different concentrations of extracellular Ca2+ define distinct transcriptional programs. Our transcriptional profiling also pointed to two putative novel Ca2+-binding proteins, encoded by the NCU08524 and NCU06607 genes, and provides a reference dataset for future investigations on the role of Ca2+ in fungal biology.

9.
J Phys Condens Matter ; 25(6): 066010, 2013 Feb 13.
Article in English | MEDLINE | ID: mdl-23315489

ABSTRACT

Magnetic properties of the intermetallic compound U(2)Fe(3)Ge were studied on a single crystal. The compound crystallizes in the hexagonal Mg(2)Cu(3)Si structure, an ordered variant of the MgZn(2) Laves structure (C14). U(2)Fe(3)Ge displays ferromagnetic order below the Curie temperature T(C) = 55 K and presents an exception to the Hill rule, as the nearest inter-uranium distances do not exceed 3.2 Å. Magnetic moments lie in the basal plane of the hexagonal lattice, with the spontaneous magnetic moment M(s) = 1.0 µ(B)/f.u. at T = 2 K. No anisotropy within the basal plane is detected. In contrast to typical U-based intermetallics, U(2)Fe(3)Ge exhibits very low magnetic anisotropy, whose field does not exceed 10 T. The dominance of U in the magnetism of U(2)Fe(3)Ge is suggested by the (57)Fe Mössbauer spectroscopy study, which indicates very low or even zero Fe moments. Electronic structure calculations are in agreement with the observed easy-plane anisotropy but fail to explain the lack of an Fe contribution to the magnetism of U(2)Fe(3)Ge.


Subject(s)
Crystallography, X-Ray , Ferric Compounds/chemistry , Germanium/chemistry , Magnetics , Uranium/chemistry , Anisotropy , Spectroscopy, Mossbauer , Temperature
10.
J Phys Condens Matter ; 24(1): 015701, 2012 Jan 11.
Article in English | MEDLINE | ID: mdl-22133599

ABSTRACT

Electrical resistivity, transverse magnetoresistance and thermoelectric power measurements were performed on CuS high quality single crystals in the range 1.2-300 K and under fields of up to 16 T. The zero field resistivity data are well described below 55 K by a quasi-2D model, consistent with a carrier confinement at lower temperatures, before the transition to the superconducting state. The transverse magnetoresistance develops mainly below 30 K and attains values as large as 470% for a 16 T field at 5 K, this behaviour being ascribed to a band effect mechanism, with a possible magnetic field induced DOS change at the Fermi level. The transverse magnetoresistance shows no signs of saturation, following a power law with field Δρ/ρ(0) ∝ H(1.4), suggesting the existence of open orbits for carriers at the Fermi surface. The thermoelectric power shows an unusual temperature dependence, probably as a result of the complex band structure of CuS.

11.
J Phys Condens Matter ; 23(4): 045602, 2011 Feb 02.
Article in English | MEDLINE | ID: mdl-21406890

ABSTRACT

Millimetre size UZn(12) single crystals were grown by the high temperature solution growth method using zinc as the solvent. Single-crystal x-ray diffraction data confirm that this compound crystallizes in the hexagonal high temperature form of SmZn(12) (S.G. P6/mmm) and points to a U(1.01(1))Zn(11.7(1)) stoichiometry for the crystals, with ∼ 4% of the U atoms being located at the 2c site due to the partial substitution of 4h Zn pairs. UZn(12) orders antiferromagnetically at T(N) = 5.0(2) K, and the magnetization and resistivity measurements suggest that the magnetic moments are confined within the a-b plane. The Sommerfeld coefficient, derived from the paramagnetic region by the standard method, is γ(p)≈200 mJ (mol K(2))( - 1), which definitely classifies UZn(12) as a moderate heavy-fermion system. The heavy-fermion character of UZn(12) is also manifested in the overall shape of temperature-dependent electrical resistivity that is dominated by a single-ion Kondo effect at high temperatures and coherent Kondo scattering at low temperatures. The paramagnetic magnetoresistivity isotherms can be fairly well superimposed onto each other using Schlottmann's scaling for the single-ion Kondo model, as expected for a Kondo system.

12.
J Phys Condens Matter ; 22(12): 125601, 2010 Mar 31.
Article in English | MEDLINE | ID: mdl-21389493

ABSTRACT

Phase equilibria in the system U-Pd-B were established at 850 °C by light optical microscopy (LOM) and x-ray powder and single crystal diffraction. Whereas in as-cast alloys only one ternary compound, τ(1)-U(2 + x)Pd(21 - x)B(6), was found to form at x ∼ 0.5, a further compound τ(2) with hitherto unknown structure was observed in alloys annealed at 850 °C. Due to the formation of suitable single crystals, the crystal structures of two binary compounds, UB(12) and UPd(3) have been redetermined from high precision x-ray data. Similarly, the crystal structure of τ(1)-U(2.5)Pd(20.5)B(6) was investigated by single crystal x-ray diffraction (XRD) revealing isotypism with the Cr(23)C(6)-type, (space group [Formula: see text]; a = 1.1687(5) nm; R(F)(2) = Σ|F(0)(2) - F(c)(2)|/ΣF(0)(2) = 0.021). τ(1)-U(2 + x)Pd(21 - x)B(6) is a partially ordered compound where 0.37(1)U + 0.63Pd atoms randomly share the 4a site in (0, 0, 0). Whereas mutual solubility of U-borides and Pd-borides was found at 850 °C to be below 1.0 at.%, a large homogeneity region of fcc-Pd(U, B) extends into the ternary system. U(2.5)Pd(20.5)B(6) has metallic behavior; the ground state properties are determined from a balance of the Kondo effect and the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction, revealing long range antiferromagnetic ordering below 6 K. An extraordinarily large Sommerfeld value (γ > 500 mJ mol(-1) K(-2)) groups U(2.5)Pd(20.5)B(6) among heavy fermion materials.

13.
Chemosphere ; 74(10): 1292-300, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19118864

ABSTRACT

A greenhouse experiment was conducted to evaluate the effect of three different organic residues, sewage sludge (SS), municipal solid waste compost (MSWC), and garden waste compost (GWC), as immobilizing agents in aided phytostabilization of a highly acidic metal-contaminated soil, affected by mining activities, using perennial ryegrass (Lolium perenne L.). The organic residues were applied at 25, 50 and 100 Mg ha(-1) (dry weight basis), and their effects on soil chemical characteristics and on relative plant growth and metal concentrations were assessed. All the organic residues tested immobilized Cu, Pb and Zn, decreasing their mobile fractions. This was corroborated by negative correlations obtained between mobile Cu, Pb and Zn and other soil chemical characteristics, which rose as a consequence of the amendments applied (i.e., pH, electrical conductivity, organic matter, nitrogen content, available P and available K), and by the multivariate exploratory techniques performed that showed an inverse correlation between these groups of variables. The greatest increase in ryegrass relative growth (more than three times) was obtained in the presence of 50 MgMS WC ha(-1), followed by SS at the same application dosage. GWC did not contribute to an increase in shoot growth, due to its small capacity to correct soil acidity and to supply essential macronutrients (N, P, K). No extractant was able of demonstrating by a linear correlation the uptake of Cu, Pb and Zn by ryegrass. This plant was therefore not a good "indicator" of Cu, Pb and Zn availability in the soil. The results obtained in this study suggest that ryegrass can be used in aided phytostabilization for this type of mine contaminated soils and that MSWC, and to a minor extent SS, applied at 50Mg ha(-1), were effective in the in situ immobilization of metals, improving soil chemical properties and leading to a large increase in plant biomass.


Subject(s)
Lolium/metabolism , Metals, Heavy/metabolism , Sewage/chemistry , Soil Pollutants/metabolism , Soil/analysis , Analysis of Variance , Biodegradation, Environmental , Lolium/growth & development , Mining
14.
Chemosphere ; 74(10): 1301-8, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19091381

ABSTRACT

Sewage sludge (SS), municipal solid waste compost, and garden waste compost (GWC) were used as immobilizing agents in aided phytostabilization of an acid metal-contaminated soil affected by mining activities. The organic residues were applied at 25, 50 and 100 Mg ha(-1) (dry weight basis) and perennial ryegrass (Lolium perenne L.) was used as a "green cover". We studied the effects of the treatments on soil phytotoxicity and enzymatic activities, and on the composition and toxicity of the soil leachate towards Vibrio fischeri and Daphnia magna. Application of SS led to the greatest values of dehydrogenase, acid phosphatase, beta-glucosidase, protease and urease activities, corresponding to the greatest overall microbial and biochemical activity in amended soils. Conversely, GWC did not increase these enzymatic activities, relative to the unamended soil, or enhance ryegrass growth. Cellulase activity increased with increasing application rates of the amendments tested, but decreased at the highest SS application rate. The organic amendments were able to suppress soil toxicity to levels that did not affect D. magna, when applied at 50 and 100 Mg ha(-1), but SS, at the same application rates, increased the soil leachate toxicity towards V. fischeri. Moreover, ryegrass showed some phytotoxic symptoms when 100 Mg ha(-1) of SS were applied. This study showed the importance of an integrated evaluation of soil quality on remediation processes. Although SS immobilized trace metals and corrected soil acidity, improving soil biochemical status, when used at high application rates it led to toxicity of soil leachate towards V. fischeri, decreased soil cellulase activity and impaired ryegrass growth.


Subject(s)
Lolium/metabolism , Metals, Heavy/metabolism , Sewage/chemistry , Soil Pollutants/metabolism , Soil/analysis , Aliivibrio fischeri/drug effects , Analysis of Variance , Animals , Biodegradation, Environmental , Daphnia/drug effects , Enzymes/metabolism , Lolium/growth & development , Mining , Soil Pollutants/toxicity
15.
J Phys Condens Matter ; 21(30): 305401, 2009 Jul 29.
Article in English | MEDLINE | ID: mdl-21828549

ABSTRACT

Novel ternary compounds, M(2)Pd(14+x)B(5-y) (M =  La, Ce, Pr, Nd, Sm, Eu, Gd, Lu, Th; x∼0.9, y∼0.1), have been synthesized by arc melting. The crystal structures of Nd(2)Pd(14+x)B(5-y) and Th(2)Pd(14+x)B(5-y) were determined from x-ray single-crystal data and both are closely related to the structure type of Sc(4)Ni(29)B(10). All compounds were characterized by Rietveld analyses and found to be isotypic with the Nd(2)Pd(14+x)B(5-y) type. Measurements of the temperature dependent susceptibility and specific heat as well as the temperature and field dependent resistivity were employed to derive basic information on bulk properties of these compounds. The electrical resistivity of M(2)Pd(14+x)B(5-y), in general, is characterized by small RRR (residual resistance ratio) values originating from defects inherent to the crystal structure. Whereas the compounds based on Ce, Nd, Sm and Gd exhibit magnetic order, those based on Pr and Eu seem to be non-magnetic, at least down to 400 mK. While the non-magnetic ground state of the Pr based compound is a consequence of crystalline electric field effects in the context of the non-Kramers ion Pr, the lack of magnetic order in the case of the Eu based compound results from an intermediate valence state of the Eu ion.

16.
Sci Total Environ ; 406(1-2): 43-56, 2008 Nov 15.
Article in English | MEDLINE | ID: mdl-18799197

ABSTRACT

A microcosm experiment was carried out to evaluate the effects of municipal solid waste compost (MSWC) or garden waste compost (GWC), and liming materials in the rehabilitation of a soil affected by mining activities, and to study the use of perennial ryegrass (Lolium perenne L.) for phystostabilization. The performance of the amendments was assessed by soil chemical parameters, total and bioavailable metals (Cu, Pb and Zn), soil enzymatic activities, and plant relative growth and mineral composition. In general, both composts corrected soil acidity and increased the total organic matter content of the soil, although with a better performance in the case of MSWC, especially when considering total N and available P and K levels in the amended soil. The application of both composts and liming materials led to a decrease in the mobile fractions of Cu, Pb and Zn, but mobilisable fractions of Cu and Zn increased with MSWC application. Plant biomass increased more than three times in the presence of 50 Mg MSWC ha(-1) and with the combined use of 25 or 50 Mg MSWC ha(-1) and CaO, but no significant differences were observed when GWC was applied. Plant tissue analysis showed that the treatments did not significantly reduce Cu, Pb and Zn uptake by the plant. Dehydrogenase, and the enzymes related to the N-cycle, urease and protease, had increased activities with increasing MSWC application rate. Conversely, the enzymatic activities of both enzymes related to the C-cycle, cellulase and beta-glucosidase, were only positively affected by GWC application, a compost obtained from raw materials rich in C. Principal component analyses evidenced this clear separation between the effect of MSWC on soil enzymes related to the N-cycle and of GWC on soil enzymes related to the C-cycle. This study indicates that MSWC (50 Mg ha(-1), limed or unlimed) can be used successfully in the remediation of a highly acidic metal-contaminated soil, allowing the establishment of perennial ryegrass.


Subject(s)
Calcium Compounds/pharmacokinetics , Enzymes , Lolium/drug effects , Mining , Oxides/pharmacokinetics , Refuse Disposal , Soil Pollutants , Biological Availability , Calcium Compounds/analysis , Cities , Endopeptidases/analysis , Endopeptidases/metabolism , Environmental Monitoring , Enzymes/analysis , Enzymes/metabolism , Hydrogen-Ion Concentration , Lolium/growth & development , Lolium/metabolism , Metals/analysis , Metals/pharmacokinetics , Nitrogen/analysis , Nitrogen/pharmacokinetics , Oxides/analysis , Oxidoreductases/analysis , Oxidoreductases/metabolism , Phosphorus/analysis , Phosphorus/pharmacokinetics , Principal Component Analysis , Risk Assessment , Soil Pollutants/analysis , Soil Pollutants/pharmacokinetics , Urease/analysis , Urease/metabolism
17.
Chemosphere ; 72(11): 1774-81, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18547605

ABSTRACT

A greenhouse pot experiment was conducted to evaluate the effect of sewage sludge (SS), of sugar beet sludge (SBS), or of a combination of both, in the remediation of a highly acidic (pH 3.6) metal-contaminated soil, affected by mining activities. The SS was applied at 100 and 200 Mg ha(-1) (dry weight basis), and the SBS at 7 Mg ha(-1). All pots were sown with Italian ryegrass (Lolium multiflorum Lam.). After 60 d of growth, shoot biomass was quantified and analysed for Cu, Pb and Zn. The pseudo-total and bioavailable contents of Cu, Pb and Zn and the enzymatic activities of beta-glucosidase, acid phosphatase, cellulase, protease and urease were determined in the soil mixtures. Two indirect acute bioassays with leachates from the soil (luminescent inhibition of Vibrio fischeri and Daphnia magna immobilization) were also used. The SS, in particular when in combination with SBS, corrected soil acidity, while increasing the total organic matter content and the cation exchange capacity. The application of SS led to a decrease in the level of effective bioavailable metals (extracted by 0.01 M CaCl(2), pH 5.7, without buffer), but caused an increase in their potential bioavailability (extracted by a solution of 0.5M NH(4)CH(3)COO, 0.5 M CH(3)COOH and 0.01 M EDTA, pH 4.7). Plant biomass increased more than 10 times in the presence of 100 Mg SS ha(-1), and more than five times with the combined use of 100 Mg SS ha(-1) and SBS, but a considerable phytotoxic effect was observed for the application rate of 200 Mg SS ha(-1). Copper, Pb and Zn concentrations in the shoots of L. multiflorum decreased significantly when using 100 Mg SS ha(-1) or SBS. The activities of beta-glucosidase, urease and protease increased with increasing SS applications rates, but cellulase had a reduced activity when using 200 Mg ha(-1)SS. Both amendments were able to suppress soil toxicity to levels that did not affect D. magna, but increased the soil leachate toxicity towards V. fischeri, especially with the application of 200 Mg SS ha(-1). This study showed that for this type of mine soils, and when using SS of similar composition, the maximum SS application rate should be 100 Mg ha(-1), and that liming the SS amended soil with SBS did not contribute to a further improvement in soil quality.


Subject(s)
Mining , Sewage/chemistry , Soil Pollutants/analysis , Soil/analysis , Aliivibrio fischeri/drug effects , Animals , Cities , Daphnia/drug effects , Ecosystem , Environmental Pollution/analysis , Environmental Pollution/prevention & control , Environmental Restoration and Remediation , Industrial Waste , Lolium/growth & development , Lolium/metabolism , Soil Pollutants/chemistry , Soil Pollutants/toxicity
18.
Environ Geochem Health ; 30(2): 95-9, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18246433

ABSTRACT

An acid metal-contaminated soil from the Aljustrel mining area (a pyrite mine located in SW Portugal in the Iberian Pyrite Belt) was subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn). Water-soluble metals were determined and a sequential extraction procedure was used to investigate metal speciation. Two bioavailable metal fractions were determined: a mobile fraction and a mobilisable fraction. Soil ecotoxicity was studied using a battery of bioassays: plant growth test and seed germination with cress (Lepidium sativum L.), earthworm (Eisenia fetida) mortality, E. fetida avoidance behaviour, luminescent inhibition of Vibrio fischeri and Daphnia magna immobilisation. Although the total content of Cu, Zn and Pb in the soil was large (362, 245 and 1,250 mg/kg dry matter, respectively), these metals were mostly structurally bound (87% for Cu, 81% for Zn and 89% for Pb) and, therefore, scarcely bioavailable. Nonetheless, the D. magna immobilization test using soil leachate showed an EC50 (48 h) of 36.3% (v/v), and the luminescent inhibition of V. fischeri presented an EC20 (15 min) of 45.2% and an EC20 (30 min) of 10.7% (v/v), suggesting a considerable toxic effect. In the direct exposure bioassays, E. fetida avoided the mine soil at the highest concentrations (50%, 75% and 100% v/v). At the same soil concentrations, cress showed negligible growth. The results suggest the need to use a battery of toxicity tests, in conjunction with chemical methods, in order to assess the quality of mine-contaminated soils correctly.


Subject(s)
Iron , Metals, Heavy/toxicity , Mining , Soil Pollutants/toxicity , Sulfides , Aliivibrio fischeri/drug effects , Aliivibrio fischeri/metabolism , Animals , Avoidance Learning/drug effects , Daphnia/drug effects , Daphnia/physiology , Environmental Monitoring , Germination/drug effects , Lepidium sativum/drug effects , Lepidium sativum/growth & development , Luminescence , Metals, Heavy/analysis , Motor Activity/drug effects , Oligochaeta/drug effects , Oligochaeta/physiology , Portugal , Seeds/drug effects , Seeds/growth & development , Soil Pollutants/analysis
19.
Environ Int ; 33(4): 505-13, 2007 May.
Article in English | MEDLINE | ID: mdl-17188749

ABSTRACT

The use of organic waste and compost as a source of organic matter and nutrients is a common practice to improve soil physico-chemical properties, meanwhile reducing the need for inorganic fertilisers. Official guidelines to assess sewage sludge and compost quality are mostly based on total metal content of these residues. Measurement of the total concentration of metals may be useful as a general index of contamination, but provides inadequate or little information about their bioavailability, mobility or toxicity when the organic residue is applied to the soil. However, ecotoxicity tests provide an integrated measure of bioavailability and detrimental effects of contaminants in the ecosystem. In the present study, three different types of biodegradable organic residues (BORs) have been considered: sewage sludge from municipal wastewater treatment (SS), compost from the organic fraction of unsorted municipal solid waste (MSWC), and garden waste compost (GWC). The BORs were subjected to chemical characterisation and total metal quantification (Cd, Cr, Cu, Ni, Pb and Zn), in order to verify their suitability for land application. Water leachability was determined through the DIN 38414-S4 method, while the modified BCR sequential extraction procedure was used for metal speciation. Ecotoxicity of the BORs was studied by direct and indirect bioassays. Direct toxicity bioassays were: plant growth tests with cress (Lepidium sativum L.) and barley (Hordeum vulgare L.), and earthworm (Eisenia fetida) mortality. On the other hand, indirect exposure bioassays, with leachate from the residues, took into account: luminescent bacteria (Vibrio fischeri), seed germination (L. sativum and H. vulgare) and Daphnia magna immobilization. As far as total metal concentration is concerned, with particular reference to Zn, SS resulted neither suitable for the use in agriculture nor compatible to be disposed of as an inert material into landfill, according to the Directive 1999/31/EC. Zinc in SS was mainly present in exchangeable form (28.5%), appearing as highly bioavailable. As a consequence, SS exhibited either high ecotoxicity effects with the indirect exposure bioassays or significant mortality with the earthworm bioassay. Total content of metals in MSWC allowed its classification as "stabilised biowaste", according to 2nd draft [DG Env.A.2. Working document of Biological treatment of biowaste - 2nd draft. Directorate-General Environment, Brussels, 12th February; 2001. accessed in:http://europa.eu.int/comm/environment/waste/facts_en.htm, at 10/09/2002] while leachate, on the basis of the concentration of these contaminants, could be classified as "inert waste". This residue showed significant ecotoxicity effects with direct exposure bioassays as well as with the luminescent bacteria bioassay. However, it resulted less toxic than SS. Finally, GWC could be classified as a Class 2 compost, with no detectable toxic effects on the organisms used in the bioassays, except for the luminescent bacteria. In this case, an EC(50) of 73.0% was observed. Considering the results, the use of a battery of toxicity test in conjunction with chemical analysis should be suggested, in order to correctly assess possible environmental risks deriving from disposal or land application of biodegradable organic residues.


Subject(s)
Agriculture , Animals , Biological Assay , Ecosystem , Soil Pollutants/toxicity
20.
Sao Paulo Med J ; 118(4): 118-20, 2000 Jul 06.
Article in English | MEDLINE | ID: mdl-10887389

ABSTRACT

CONTEXT: Paranasal sinus cancer is considered rare, with an incidence of less than 1 per 100,000 per year, with the frontal sinus being the primary site in only 0.3%. We report a case of adenocarcinoma arising in the frontal sinus. DESIGN: Case report. CASE REPORT: A 59-year-old woman, secretary, came in February 1998 with a 4-month history of low intensity frontal headache. She denied contact with wood dust. On examination a non-tender swelling was noted over her right forehead next to the medial aspect of the right orbit. CT scan showed a soft-tissue mass involving frontal sinus with intracranial invasion through the posterior wall. The anterior ethmoid sinus and the medial aspect of the right orbit were also involved. MRI demonstrated dural thickening in communication with the frontal mass. She underwent an en-bloc tumor resection by craniotomy including orbital clearance. Histology revealed an adenocarcinoma. After surgery she had tumor recurrence, and chemotherapy and radiotherapy were started resulting in partial improvement.


Subject(s)
Adenocarcinoma/diagnosis , Frontal Sinus , Paranasal Sinus Neoplasms/diagnosis , Female , Humans , Magnetic Resonance Imaging , Middle Aged , Neoplasm Recurrence, Local , Tomography, X-Ray Computed
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