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1.
Prog Urol ; 32(2): 92-100, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34920923

ABSTRACT

BACKGROUNDS: Spermatic cord torsion is a frequent urological emergency that mostly concerns teenagers and young adults. This study aimed to determine the clinical and surgical characteristics of young adults who had scrotal exploration for suspected spermatic cord torsion and to identify clinical risk factors associated with needless scrotal exploration. METHODS: We retrospectively collected national data from patients aged 12years and older who underwent a surgical exploration for suspicion of torsion of the spermatic cord between 2005 and 2019 in 17 hospitals. We analyzed demographics, surgical and postoperative characteristics in our population. We compared the cohort according to the intraoperative diagnosis of torsion or not. RESULTS: In total, 2940 had surgical exploration: 1802 (61.3%) patients had torsion of the spermatic cord and 1138 (38.7%) had another diagnosis. In multivariate analysis, age (OR: 1.04; 95% CI: 1.01-1.06; P=0.005), medical history of cryptorchism (OR: 4.14; 95% CI: 1.05-16.31; P=0.042) and VAS pain score (OR: 0.91; 95% CI: 0.83-0.98; P=0.018) were risk factors significantly associated with unnecessary surgical exploration. The rate of complications in the 90days after surgery was 11% in the "torsion" group, and 9.7% in the "non-torsion" group (P=0.28). CONCLUSION: Scrotal exploration without intraoperative diagnosis of torsion was performed in 40% of our cohort. VAS pain score and cryptorchism history can help for the diagnosis but scrotal exploration remains the way to diagnose spermatic cord torsion and should be performed on the slightest suspicion, even after 24hours of symptoms, as the chances for testicular salvage remains around 50%.


Subject(s)
Spermatic Cord Torsion , Spermatic Cord , Adolescent , Child , Humans , Male , Retrospective Studies , Risk Factors , Scrotum , Spermatic Cord Torsion/diagnosis , Spermatic Cord Torsion/epidemiology , Spermatic Cord Torsion/surgery , Unnecessary Procedures , Young Adult
2.
Ecotoxicol Environ Saf ; 161: 281-289, 2018 10.
Article in English | MEDLINE | ID: mdl-29886315

ABSTRACT

The aim of this study was to evaluate the use of drinking-water treatment residuals (DWTR) in the amendment of a soil affected by mining activities (Aljustrel mine, Portuguese sector of the Iberian Pyrite Belt), considering the effects on its chemical, biochemical and ecotoxicological characteristics. The DWTR had neutral characteristics (pH 6.7) and an organic matter (OM) content of 575 g kg-1 dry matter (DM), which makes them a potential amendment for the remediation of mine degraded soils, as they may correct soil acidity and reduce the extractable metal fraction. An incubation assay, with soil and DWTR, with or without lime, was carried out to test the doses to be used in the assisted-phytostabilization experiment. Based on the results obtained, the doses of DWTR used were the equivalent to 48, 96, and 144 t DM ha-1, with and without lime application (CaCO3 11 t DM ha-1). Agrostis tenuis Sibth was used as the test plant. Some amendments doses were able to improve soil characteristics (pH and OM content), to decrease metal extractability by 0.01 M CaCl2 (especially for Cu and Zn), and to allow plant growth, that did not occur in the non-amended soil. Copper, Pb and Zn concentrations in the plant material were lower than the maximum tolerable level for cattle feed, used as an indicator of risk of entry of those metals into the human food chain. The simultaneous application of DWTR (96 and 144 t ha-1), with lime, allowed a reduction in the mine soil ecotoxicity, as evaluated by some lethal and sub-lethal bioassays, including luminescence inhibition of Vibrio fischeri, Daphnia magna acute immobilization test, mortality of Thamnocephalus platyurus, and 72-h growth inhibition of the green microalgae Pseudokirchneriella subcapitata. However, DWTR were unable to increase soil microbial activity, evaluated by dehydrogenase activity, an important soil-health indicator. Also, OM content and NKjeldahl, concentrations increased slightly but remained low or very low (P and K extractable concentrations were not affected). In general, the bioassays highlighted a decrease in soil ecotoxicity with the presence of lime and DWTR (144 t DM ha-1). In conclusion, DWTR are recommended to amend acidic soils, with high concentrations of trace elements, but an additional application of organic or mineral fertilizers should be considered.


Subject(s)
Environmental Restoration and Remediation/methods , Fertilizers/analysis , Mining , Soil/chemistry , Waste Products/analysis , Water Purification , Aliivibrio fischeri/drug effects , Animals , Daphnia/drug effects , Ecotoxicology , Metals, Heavy/analysis , Metals, Heavy/toxicity , Plant Development/drug effects , Portugal , Refuse Disposal , Soil Pollutants/analysis , Soil Pollutants/toxicity
3.
Int J Phytoremediation ; 16(2): 138-54, 2014.
Article in English | MEDLINE | ID: mdl-24912206

ABSTRACT

A semi-field experiment was conducted to evaluate the use of mixed municipal solid waste compost (MMSWC) and green waste-derived compost (GWC) as immobilizing agents in aided-phytostabilization of a highly acidic soil contaminated with trace elements, with and without a plant cover of Agrostis tenuis. The compost application ratio was 50 Mg ha(-1), and GWC amended soil was additionally limed and supplemented with mineral fertilizers. Both treatments had an equivalent capacity to raise soil organic matter and pH, without a significant increase in soil salinity and in pseudo-total As, Cu, Pb, and Zn concentrations, allowing the establishment of a plant cover. Effective bioavailable Cu and Zn decreased as a consequence of both compost treatments, while effective bioavailable As increased by more than twice but remained as a small fraction of its pseudo-total content. Amended soil had higher soil enzymatic activities, especially in the presence of plants. Accumulation factors for As, Cu, Pb, and Zn by A. tenuis were low, and their concentrations in the plant were lower than the maximum tolerable levels for cattle. As a consequence, the use of A. tenuis can be recommended for assisted phytostabilization of this type of mine soil, in combination with one of the compost treatments evaluated.


Subject(s)
Agrostis/growth & development , Soil Pollutants/metabolism , Soil/chemistry , Trace Elements/metabolism , Biodegradation, Environmental , Biomass , Environmental Monitoring , Environmental Pollution , Fertilizers , Mining , Plant Shoots/growth & development , Soil Pollutants/analysis , Trace Elements/analysis
4.
J Hazard Mater ; 192(3): 1836-41, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-21802201

ABSTRACT

In soils impacted by mining activities a vegetal cover is required to protect the site from the erosive forces of water and wind. The success of this objective depends on plant establishment and canopy closure. Polyacryalate polymers aid the growth of crops and indigenous plants in soils from sulfide mines. Soil characteristics change as a consequence of polymer application, but indicators that pinpoint these changes have not been identified yet. Our objectives were to (1) identify the sensitive indicators of changes in soil quality following polymer application, (2) relate these with assessment based on plant growth and soil cover. A mine soil was left unamended or received a characterized polyacrylate, a polyacrylate removed from diapers, or shredded diapers. Biomass of Spergularia purpurea was measured and proportion of soil cover evaluated. Soil enzymes, microbial activity, and respiration were analyzed. Availability of potentially toxic trace elements was estimated by their concentration in shoots. Factor analysis identified three factors that accounted for 94% of the variation in parameters, and the scores separated the four treatments. The indicators with greatest communality were correlated with plant growth and soil cover. The best soil quality indicators were As and Zn in shoots, protease, ß-glucosidase, and fructose-induced respiration. It seems that the most important indicators to be used to assess the restoration of sulfide mine soils are those related with bioavailability of trace elements and soil enzymatic activities.


Subject(s)
Mining , Polymers/chemistry , Soil Pollutants/analysis , Soil/analysis , Sulfides/chemistry , Arsenic/chemistry , Biomass , Environmental Monitoring/methods , Environmental Pollutants , Fructose/metabolism , Industrial Waste/analysis , Peptide Hydrolases/chemistry , Trace Elements/chemistry , Zinc/chemistry , beta-Glucosidase/metabolism
5.
J Hazard Mater ; 178(1-3): 956-62, 2010 Jun 15.
Article in English | MEDLINE | ID: mdl-20207477

ABSTRACT

We used hydrophilic polymers from diapers to aid the establishment of an indigenous plant (Spergularia purpurea (Persoon) G. Don fil.) in a soil from a pyrite mine. Lysimeters were filled with the mine soil with no amendment (control), with a polyacrylate polymer, with a polymer removed from diapers, and with shredded diapers. The establishment of a plant cover was faster in soil amended with polymer from diapers, and 85 days after sowing the soil was completely covered in all treatments except control. The concentrations of trace elements in plant shoots decreased in amended soil. The activities of soil acid phosphatase, beta-glucosidase, protease and cellulase were greatest in soil amended with the polyacrylate polymer or with polymer removed from diapers, while the application of shredded diapers leads to values that were in general intermediate between these treatments and unamended control. Basal- and substrate-induced respirations, and dehydrogenase were greatest in soil amended with polymers, but the presence of a plastic film and fibrous materials from shredded diapers prevented any improvement in these parameters compared with unamended soil. In the second experiment, we evaluated the risk of downward movement of polymers in columns of a sandy soil. Polymer from diapers, with or without Cu, was placed at a 10 cm-depth. Five leaching cycles with artificial rain took place and leachates were analyzed for organic matter and Cu. At the end of the experiment, the soil columns were sliced and each layer was analyzed separately. Some repacking of soil and polymer particles took place, but there was no indication that polymers moved to any great depth in soil columns.


Subject(s)
Caryophyllaceae/growth & development , Diapers, Infant , Mining , Polymers/chemistry , Soil Pollutants/chemistry , Biomass , Caryophyllaceae/metabolism , Copper/chemistry , Hydrogen-Ion Concentration , Iron , Oxidoreductases/chemistry , Oxidoreductases/metabolism , Plant Shoots/growth & development , Plant Shoots/metabolism , Polymers/analysis , Seeds/growth & development , Soil/analysis , Soil Microbiology , Solubility , Sulfides , Temperature , Water Supply/analysis
6.
J Environ Qual ; 39(1): 168-75, 2010.
Article in English | MEDLINE | ID: mdl-20048304

ABSTRACT

We evaluated the use of polyacrylate polymers to aid phytostabilization of mine soils. In a pot experiment, perennial ryegrass was grown in a mine soil and in uncontaminated soil. Growth was stimulated in the polymer-amended mine soil compared with an unamended control, and water-extractable levels of soil Cu and Zn decreased after polymer application. In an experiment performed in six 60-cm-diameter cylinders filled with fertilized mine soil, polymers were applied to three cylinders, with the remainder used as unamended control. Total biomass produced by indigenous plant species sown in polymer-amended soil was 1.8 (Spring-Summer) or 2.4 times (Fall-Winter) greater than that of plants from unamended soil. The application of polymers to the mine soil led to the greatest activity of soil enzymes. Soil pH, biomass of Spergularia purpurea and Chaetopogon fasciculatus, and activities of protease and cellulase had large loadings on principal component (PC)1, whereas growth of Briza maxima and the activities of urease, acid phosphatase, and beta-glucosidase had large loadings on PC2. The treatments corresponding to controls were located on the negative side of PC1 and PC2. Amended treatments were on the positive side of PC2 (Spring-Summer) or on the positive side of PC1 (Fall-Winter), demonstrating differential responses of plants and soil parameters in the two growth cycles.


Subject(s)
Acrylates/chemistry , Biodegradation, Environmental , Plant Development , Polymers/chemistry , Soil/analysis , Environmental Monitoring , Industrial Waste , Mining , Soil Pollutants/chemistry , Soil Pollutants/metabolism
7.
J Hazard Mater ; 173(1-3): 570-5, 2010 Jan 15.
Article in English | MEDLINE | ID: mdl-19775813

ABSTRACT

Contamination of soils with cadmium (Cd) is a serious global issue due to its high mobility and toxicity. We investigated the application of insoluble polyacrylate polymers to improve soil and plant health. Sorghum was grown in a Cd-contaminated sandy soil. Polyacrylate polymers at 0.2% (w/w) were added to half of the soil. Control soil without plants was also included in the experiment. Growth of sorghum was stimulated in the polymer-amended soil. The concentration of Cd in the shoots, and the activities of catalase and ascorbate peroxidase decreased in plants from polymer-amended soil compared with unamended control. The amount of CaCl(2)-extractable Cd in the polymer-amended soil was 55% of that in the unamended soil. The Cd extracted in sorghum shoots was 0.19 mg per plant grown on soil without polymer and 0.41 mg per plant grown on polymer-amended soil. The total amount of Cd removed from each pot corresponded to 1.5 and more than 6% of soil CaCl(2)-extractable Cd in unamended and polymer-amended soil, respectively. The activities of soil acid phosphatase, beta-glucosidase, urease, protease and cellulase were greatest in polymer-amended soil with sorghum. In conclusion, the application of polyacrylate polymers to reduce the bioavailable Cd pool seems a promising method to enhance productivity and health of plants grown on Cd-contaminated soils.


Subject(s)
Acrylic Resins/pharmacology , Cadmium/toxicity , Soil Pollutants/toxicity , Soil/analysis , Sorghum/physiology , Acid Phosphatase/metabolism , Ascorbate Peroxidases , Cadmium/analysis , Cadmium/metabolism , Catalase/metabolism , Cellulase/metabolism , Peroxidases/metabolism , Plant Shoots/chemistry , Plant Shoots/genetics , Plant Shoots/metabolism , Soil Pollutants/analysis , Sorghum/growth & development , Sorghum/metabolism , Spectrophotometry, Ultraviolet , Superoxide Dismutase/metabolism , Urease/metabolism , beta-Glucosidase/metabolism
8.
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
9.
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
10.
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
11.
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
12.
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
13.
Sci Total Environ ; 326(1-3): 239-47, 2004 Jun 29.
Article in English | MEDLINE | ID: mdl-15142779

ABSTRACT

This article describes an experiment, carried out under controlled environment conditions, to investigate the effects of a fulvic acid fraction of soil organic matter on growth, cadmium (Cd) uptake and redistribution by sorghum. In addition the uptake of copper (Cu), zinc (Zn) and iron (Fe) was also determined. Sorghum was grown in nutrient solutions with 0, 0.1, 1 and 10 mg Cd dm(-3), in the absence and presence of organic matter (32 mg C dm(-3)), for various periods up to 20 days. A decrease in sorghum biomass due to Cd toxicity was observed at 10 mg Cd dm(-3), but for concentrations of 0.1 and 1 mg Cd dm(-3) the biomass was increased compared with control, without visual toxicity symptoms. The presence of organic matter (OM) further increased biomass production. Cadmium was mainly retained in sorghum roots, as usually found in tolerant plants, but Cd accumulation in sorghum was greater than in other Gramineae, or even more tolerant plants such as lettuce. The presence of OM decreased the bioavailability of Cd that was partially retained in solution by the OM ligands. However, OM promoted the translocation of Cd to shoots, an effect that may pose a risk to public health because plant-animal transfer of Cd could be enhanced. The presence of OM decreased the uptake of Cu, Zn and Fe. The presence (vs. absence) of 0.1 mg Cd dm(-3) enhanced the uptake of Fe, both in the absence and presence of OM.


Subject(s)
Benzopyrans/pharmacology , Food Contamination , Metals, Heavy/pharmacokinetics , Poaceae/chemistry , Soil Pollutants/pharmacokinetics , Sorghum/chemistry , Animals , Biomass , Drug Resistance , Humans , Poaceae/growth & development , Public Health , Risk Assessment , Sorghum/growth & development , Vegetables/chemistry
14.
J Enzyme Inhib ; 16(3): 251-7, 2001.
Article in English | MEDLINE | ID: mdl-11697045

ABSTRACT

Aspartate aminotransferase (AAT, EC 2.6.1.1) catalyses the transamination of L-asparate to oxaloacetate. It has been reported that AAT from different plant sources can catalyse the transamination of other compounds structurally similar to the natural substrates. Specificity and kinetic studies were performed with two aspartate aminotransferase isoenzymes (AAT-1 and AAT-2) from leaves of Lupinus albus L. cv Estoril using different amino donors and acceptors. Both isoenzymes showed residual activity for some of the substrates tested. Competitive inhibition was found with most of the structural analogues which is typical of a ping-pong bi-bi kinetic mechanism. It was found that both isoenzymes can use 2-amino-4-methoxy-4-oxobutanoic acid as amino donor. AAT-2 uses 2-amino-4-methoxy-4-oxobutanoic acid at a similar rate as L-aspartate but AAT-1 uses this substrate at a slower rate. The use of this amino donor by AAT isoenzymes has not been reported previously, and our results indicate structural differences between both isoenzymes.


Subject(s)
Aspartate Aminotransferases/metabolism , Fabaceae/enzymology , Isoenzymes/metabolism , Amino Acids/chemistry , Amino Acids/metabolism , Aspartate Aminotransferases/antagonists & inhibitors , Aspartate Aminotransferases/isolation & purification , Binding Sites , Binding, Competitive , Butyrates/chemistry , Butyrates/metabolism , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Isoenzymes/isolation & purification , Ketoglutaric Acids/metabolism , Plant Leaves/enzymology , Plant Proteins/metabolism , Substrate Specificity
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