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1.
Ecotoxicology ; 30(6): 1029-1042, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34191243

RESUMEN

Lead acetate (AcPb) is an important raw material used in chemical industries worldwide. The potential toxicity of AcPb is generally attributed to the presence of Pb. However, the effect of AcPb on the environment as a whole is still poorly known. This study aimed to evaluate AcPb toxicity on three standard species of soil invertebrates and two plant species using ecotoxicology tests. Three tropical soils (Oxisol, Inceptisol, and Tropical Artificial Soil (TAS)) were contaminated with different concentrations of AcPb and one dose of K-acetate (positive control). These soils were used in tests with Eisenia andrei (earthworm), Folsomia candida (springtail), Enchytraeus crypticus (enchytraeid), Zea mays (maize), and Phaseolus vulgaris (common bean). Dose-response curves obtained in the laboratory tests were used to estimate the EC50 values for each species. Among invertebrates, the highest sensitivity to AcPb was observed for E. crypticus in the TAS (EC50 = 29.8 mg AcPb kg-1), whereas for E. andrei and F. candida the highest sensitivity was observed in the Oxisol (EC50 = 141.9 and 1835 mg AcPb kg-1, respectively). Folsomia candida was the least sensitive invertebrate species to AcPb in all soils. Among plant species, Z. mays was less sensitive (EC50 = 1527.5 mg AcPb kg-1) than P. vulgaris (EC50 = 560.5 mg AcPb kg-1) in the Oxisol. The present study evidenced that the toxicity of AcPb should not be attributed uniquely to the presence of Pb, as the treatment containing uniquely Ac provoked the same toxicity as the highest dose of AcPb.


Asunto(s)
Artrópodos , Oligoquetos , Contaminantes del Suelo , Animales , Plomo/toxicidad , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
2.
J Appl Microbiol ; 120(6): 1501-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26991693

RESUMEN

AIMS: To isolate, characterize and determine the antibacterial activities of compounds produced by the endophytic fungus Diaporthe sp. F2934, cultivated on malt extract agar. METHODS AND RESULTS: The fungus was cultivated aseptically in Petri dishes containing malt extract agar at 25°C for 15 days. Crude extract was obtained from mycelium using ethyl acetate and sonication, and was fractioned using classic chromatography and HPLC. The structures of phomosines and chromanones were established by NMR experiments including HMQC, HMBC and COSY. Their molecular formulas were determined by ESI-TOFMS. We obtained six compounds: (1) 4H-1-benzopyra-4-one-2,3-dihydro-5-hydroxy-2,8-dimetyl, (2) 4H-1-benzopyran-4-one-2,3-dihydro-5-hydroxy-8-(hydroxylmethyl)-2-methyl, (3) 4H-1-benzopyra-4-one-2,3-dihydro-5-methoxyl-2,8-dimetyl, (4) phomosine A, (5) phomosine D and (6) phomosine C. Isolated compounds 1, 2 and 5 were inactive against 15 micro-organisms, but phomosines A and C were active against diverse Gram-negative and Gram-positive bacteria. CONCLUSIONS: A group of new chromanones and known phomosines have been isolated from the genus Diaporthe (Diaporthe sp. F2934). The results obtained confirm the wide chemical diversity produced by endophytic fungi, specifically the genus Diaporthe. In addition, phomosines A and C may be considered as antimicrobial agents that can be used to guide the development of new antibiotics. SIGNIFICANCE AND IMPACT OF THE STUDY: Our phylogenetic analysis places Diaporthe sp. F2934 as sister to the Diaporthe cynaroidis clade. Three chromanones were isolated and identified, for the first time, using crude extract obtained from Diaporthe F2934. From this extract phomosines A, C and D were also purified. Regarding Staphylococcus aureus, the inhibition zone diameter (IZD) for phomosine A was 20% higher than the standard drug, vancomycin. When cultivated as described here, Diaporthe sp. F2934 produced new and antimicrobial compounds.


Asunto(s)
Antibacterianos/farmacología , Ascomicetos/química , Bacterias/efectos de los fármacos , Cromanos/farmacología , Éteres/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Ascomicetos/clasificación , Bacterias/clasificación , Cromanos/química , Cromanos/aislamiento & purificación , Éteres/química , Éteres/aislamiento & purificación , Filogenia , Staphylococcus aureus/efectos de los fármacos
3.
Clin Genet ; 88(5): 462-7, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25307721

RESUMEN

Alport syndrome (AS) is caused by pathogenic mutations in the genes encoding α3, α4 or α5 chains of collagen IV (COL4A3/COL4A4/COL4A5), resulting in hematuria, chronic renal failure (CRF), sensorineural hearing loss (SNHL) and ocular abnormalities. Mutations in the X-linked COL4A5 gene have been identified in 85% of the families (XLAS). In this study, 22 of 60 probands (37%) of unrelated Portuguese families, with clinical diagnosis of AS and no evidence of autosomal inheritance, had pathogenic COL4A5 mutations detected by Sanger sequencing and/or multiplex-ligation probe amplification, of which 12 (57%) are novel. Males had more severe and earlier renal and extrarenal complications, but microscopic hematuria was a constant finding irrespective of gender. Nonsense and splice site mutations, as well as small and large deletions, were associated with younger age of onset of SNHL in males, and with higher risk of CRF and SNHL in females. Pathogenic COL4A3 or COL4A4 mutations were subsequently identified in more than half of the families without a pathogenic mutation in COL4A5. The lower than expected prevalence of XLAS in Portuguese families warrants the use of next-generation sequencing for simultaneous COL4A3/COL4A4/COL4A5 analysis, as first-tier approach to the genetic diagnosis of collagen type IV-related nephropathies.


Asunto(s)
Colágeno Tipo IV/genética , Mutación , Nefritis Hereditaria/diagnóstico , Nefritis Hereditaria/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Análisis Mutacional de ADN , Exoma , Femenino , Estudios de Asociación Genética , Humanos , Lactante , Masculino , Persona de Mediana Edad , Nefritis Hereditaria/metabolismo , Portugal , Adulto Joven
4.
J Clin Pharm Ther ; 38(2): 162-4, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23095052

RESUMEN

WHAT IS KNOWN AND OBJECTIVE:   Cannabis withdrawal in heavy users is commonly followed by increased anxiety, insomnia, loss of appetite, migraine, irritability, restlessness and other physical and psychological signs. Tolerance to cannabis and cannabis withdrawal symptoms are believed to be the result of the desensitization of CB1 receptors by THC. CASE SUMMARY:   This report describes the case of a 19-year-old woman with cannabis withdrawal syndrome treated with cannabidiol (CBD) for 10 days. Daily symptom assessments demonstrated the absence of significant withdrawal, anxiety and dissociative symptoms during the treatment. WHAT IS NEW AND CONCLUSION:   CBD can be effective for the treatment of cannabis withdrawal syndrome.


Asunto(s)
Cannabidiol/uso terapéutico , Cannabis/efectos adversos , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico , Adulto , Femenino , Humanos , Adulto Joven
5.
Ecotoxicol Environ Saf ; 86: 188-97, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23079741

RESUMEN

Ecological parameters (soil invertebrates, microbial activity, and plant community) were assessed in a metal contaminated site in an abandoned lead smelter and non-contaminated reference sites, as part of an ecological risk assessment (ERA). Vegetation cover inside the smelter area was lower and presented a more homogenous species composition than outside. A more simplified and less abundant vegetation community within the smelter area also simplified the habitat conditions, which in addition to metal toxicity, impaired the soil microbial and faunal communities. A significant reduction in the feeding activity was observed within the smelter area. Also a significant change in community composition of surface dwelling invertebrates was observed at those sites when compared to sites outside the smelter area. Moreover, basal respiration, microbial biomass C, dehydrogenase and phosphatase activity also decreased in several of these points under the smelter area. As a result, a significant impairment of organic material decomposition in the most contaminated sites was observed. Metal contamination affected the ecological status of the site, leading to a risk for ecosystem functioning and provisioning of ecosystem services like organic matter decomposition and nutrient cycling, even 17 years after the end of smelting activities. Regarding the sensitivity of the ecological parameters assessed, most were able to distinguish sites within the smelter area boundaries from those outside. However, only bait lamina (feeding activity), basal respiration and microbial biomass carbon presented high capacity to distinguish the level of soil contamination, since they were significantly correlated with metal loadings, and thus are promising candidates to be integrated in the Ecological Line of Evidence of an ERA.


Asunto(s)
Bacterias/efectos de los fármacos , Ecosistema , Invertebrados/efectos de los fármacos , Metales/toxicidad , Plantas/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Biomasa , Metales/análisis , Suelo/química , Microbiología del Suelo , Contaminantes del Suelo/análisis , Clima Tropical
6.
Ecotoxicology ; 21(8): 2113-22, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22711551

RESUMEN

The objective of this work was to assess the impact of pesticide application to non-target soil organisms simulating what happens following pesticide application in agricultural fields and thus obtaining higher realism on results obtained. For that purpose, three commercial formulations containing the insecticides chlorpyrifos and endosulfan and the herbicide glyphosate were applied to a Mediterranean agricultural field. The soil was collected after spraying and dilution series were prepared with untreated soil to determine the impact of the pesticides on the avoidance behaviour and reproduction of the earthworm Eisenia andrei and the collembolan Folsomia candida. A significant avoidance was observed at the recommended field dose in case of endosulfan by earthworms (60 %) and in case of chlorpyrifos by collembolans (64 %). In addition, both insecticides affected the number of juveniles produced by the earthworms (EC(50) were below the recommended field dose). Glyphosate did not seem to affect either earthworms or collembolans in the recommended field dose. Folsomia candida was more sensitive to pesticide application than Eisenia andrei, what was corroborated by the EC(50) and LC(50) values. In conclusion, insecticides may affect the structure of the soil community by reducing the survival of collembolans and the reproductive capacity of collembolans and earthworms.


Asunto(s)
Artrópodos/efectos de los fármacos , Herbicidas/toxicidad , Insecticidas/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Artrópodos/fisiología , Cloropirifos/toxicidad , Endosulfano/toxicidad , Exposición a Riesgos Ambientales , Monitoreo del Ambiente , Glicina/análogos & derivados , Glicina/toxicidad , Dosificación Letal Mediana , Actividad Motora/efectos de los fármacos , Oligoquetos/fisiología , Portugal , Reproducción/efectos de los fármacos , Especificidad de la Especie , Glifosato
7.
Ecotoxicology ; 21(3): 919-24, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22113457

RESUMEN

Boric acid (BA) has been successfully used as reference substance in some standard test guidelines. Due to the fact that previously selected reference substances present a significant risk to human health and/or are banned for environmental reasons, BA is being discussed for broader adoption in OECD or ISO guidelines. To provide input on BA data and contribute to the discussion on its suitability as a reference substance, in the present study BA was tested with two standard soil organisms, Enchytraeus albidus and Folsomia candida, in terms of survival, reproduction and avoidance. Additionally, published data on other organisms was analysed to derive the most sensitive soil dwelling invertebrate (hazard concentration-HC5). Results showed that BA affected the tested organisms, being two times more toxic for collembolans (LC50 = 96; EC50 = 54 mg/kg) than for enchytraeids (LC50 = 325; EC50 = 104 mg/kg). No avoidance behaviour occurred despite the fact that BA affects earthworms. Actually, it is the recommended reference substance for the earthworm avoidance test. Clearly, the suitable performance of BA in one species should not be generalized to other species. Absolute toxicity is not an important criterion for the selection of a reference substance, but it has been proposed that effects should occur within a reasonable range, i.e. <1,000 mg/kg. We could confirm, compiling previous data that for most soil invertebrates, the EC50 is expected to be below 1,000 mg/kg. From these data it could be derived that the most sensitive soil dwelling invertebrate (HC5, 50%) is likely to be affected (EC10) at 28 (8-53) mg H(3)BO(3)/Kg, equivalent to 4.6 (1.4-8.7) mg boron/kg.


Asunto(s)
Ácidos Bóricos/toxicidad , Insectos/efectos de los fármacos , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Pruebas de Toxicidad/normas , Animales , Reacción de Prevención/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Monitoreo del Ambiente/métodos , Reacción de Fuga/efectos de los fármacos , Guías como Asunto , Insectos/fisiología , Oligoquetos/fisiología , Estándares de Referencia
8.
J Environ Monit ; 14(3): 925-36, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22297688

RESUMEN

This study describes the first attempt to validate a Portuguese natural soil (PTRS1) to be used as reference soil for ecotoxicological purposes, aimed to both: (i) obtain ecotoxicological data for the derivation of Soil Screening Values (SSVs) with regional relevance, acting as a substrate to be spiked with ranges of concentrations of the chemicals under evaluation and (ii) act as control and as substrate for the dilution of contaminated soils in ecotoxicological assays performed to evaluate the ecotoxicity of contaminated soils, in tier 2 of risk assessment frameworks, applied to contaminated lands. The PTRS1 is a cambisol from a granitic area integrated in the Central Iberian Zone. After chemical characterization of the soil in terms of pseudo-total metals, PAHs, PCBs and pesticide contents, it was possible to perceive that some metals (Ba, Be, Co, Cr and V) surpass the Dutch Target Values (Dtvs) corrected for the percentage of organic matter and clay of the PTRS1. Nevertheless, these metals displayed total concentrations below the background total concentrations described for Portuguese soils in general. The same was observed for aldrin, endosulfan I, endosulfan II, heptachlor epoxide, and heptachlor; however the Dtvs corrected become negligible. The performance of invertebrate and plant species, commonly used in standard ecotoxicological assays, was not compromised by both soil properties and soil metal contents. The results obtained suggest that the PTRS1 can be used as a natural reference soil in ecotoxicological assays carried out under the scope of ecological risk assessment.


Asunto(s)
Contaminantes del Suelo/normas , Ecotoxicología , Metales/análisis , Metales/normas , Metales/toxicidad , Plaguicidas/análisis , Plaguicidas/normas , Plaguicidas/toxicidad , Bifenilos Policlorados/análisis , Bifenilos Policlorados/normas , Bifenilos Policlorados/toxicidad , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/normas , Hidrocarburos Policíclicos Aromáticos/toxicidad , Portugal , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
9.
Arch Environ Contam Toxicol ; 63(2): 199-208, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22476565

RESUMEN

Sewage sludge application to soils is regulated by its total metal content. However, the real risk of metals is determined by the fraction that is biologically available. The available fraction is highly related to the strength of metal binding by the matrix, which is a dynamic process. The evaluation of the fate of metals in time can contribute increased accuracy of ecological risk assessment. Aiming to evaluate short-term changes in metal availability when metals were applied to soil directly (metal-spiked) or by way of an organic matrix (sludge-amended), a laboratory experiment was performed using open microcosms filled with agricultural soil. A concentration gradient of industrial sludge (11, 15, 55, and 75 t/ha) that was contaminated predominantly with chromium, copper, nickel, and zinc, or soil freshly spiked with the same concentrations of these metals, were applied on top of the agricultural soil. After 0, 3, 6, and 12 weeks, total (HNO(3) 69 %) and 0.01 M CaCl(2)-extractable metal concentrations in soil and metal content in the percolates were measured. Results demonstrated that comparison between sludge-amended and metal-spiked soils may give important information about the role of sludge matrix on metal mobility and availability in soil. In sludge-amended soils, extractable-metal concentrations were independent of the sludge concentration and did not change over time. In metal-spiked soils, metal extractability decreased with time due to ageing and transport of metals to deeper layers. In general, the sludge matrix increased the adsorption of metals, thus decreasing their mobility in soils.


Asunto(s)
Metales Pesados/química , Aguas del Alcantarillado/química , Contaminantes del Suelo/química , Suelo/química , Fenómenos Químicos , Metales Pesados/análisis , Análisis de Regresión , Aguas del Alcantarillado/análisis , Suelo/análisis , Contaminantes del Suelo/análisis , Espectrofotometría Atómica
10.
Anaerobe ; 18(1): 31-6, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22266301

RESUMEN

The aim of this study was to examine the effects of Dorstenia asaroides extracts on cariogenic properties of the most cariogenic bacteria, Streptococcus mutans. Hexane (HFr), ethyl-acetate (EFr) and chloroform (CFr) extracts obtained from D. asaroides rhizomes were submitted to chemical analyses, Minimal Inhibitory Concentrations (MIC), glycolysis assay and S. mutans 12-h-old initial biofilms. Chemical characterization showed that all the extracts present furanocoumarins. The MIC values were 80 (HFr and CFr) and 50 µg/mL (EFr). Acid production by S. mutans cells was significantly disrupted by HFr (12.5 mg/mL), EFr (at 2.5; 6.25 and 12.5 mg/mL) and CFr (at 2.5, 6.25 and 12.5 mg/mL) (p < 0.01). Topical applications of HFr, EFr and CFr significantly reduced the colony forming units of S. mutans biofilms compared with those treated with control group in order to 20, 30 and 25% respectively (p < 0.01). The results of the present study suggest that rhizomes of D. asaroides had inhibitory effects on cariogenic properties of S. mutans.


Asunto(s)
Antibacterianos/farmacología , Moraceae/química , Extractos Vegetales/farmacología , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/metabolismo , Biopelículas/efectos de los fármacos , Glucólisis/efectos de los fármacos , Pruebas de Sensibilidad Microbiana
11.
Ecotoxicol Environ Saf ; 74(6): 1715-20, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21683441

RESUMEN

Regulatory limits for chemicals and ecological risk assessment are usually based on the effects of single compounds, not taking into account mixture effects. The ecotoxicity of metal-contaminated sludge may, however, not only be due to its metal content. Both the sludge matrix and the presence of other toxicants may mitigate or promote metal toxicity. To test this assumption, the toxicity of soils recently amended with an industrial sludge predominantly contaminated with chromium, copper, nickel, and zinc and soils freshly spiked with the same mixture of metals was evaluated through earthworm (Eisenia andrei) and collembolan (Folsomia candida) reproduction tests. The sludge was less toxic than the spiked metal mixture for E. andrei but more toxic for F. candida. Results obtained for the earthworms suggest a decrease in metal bioavailability promoted by the high organic matter content of the sludge. The higher toxicity of the sludge for F. candida was probably due to the additive toxic effect of other pollutants.


Asunto(s)
Artrópodos/efectos de los fármacos , Metales/toxicidad , Oligoquetos/efectos de los fármacos , Contaminantes del Suelo/toxicidad , Animales , Cobre/metabolismo , Cobre/toxicidad , Relación Dosis-Respuesta a Droga , Ecología , Metales/metabolismo , Medición de Riesgo , Suelo/química , Contaminantes del Suelo/metabolismo , Zinc/metabolismo , Zinc/toxicidad
12.
Arch Environ Contam Toxicol ; 59(3): 502-12, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20361322

RESUMEN

The evaluation of pollution effects on wildlife provides biologically meaningful information concerning environmental quality and possible impacts on populations and can be used as an early warning of environmental change. We aimed to assess the potential effects of exposure to atmospheric pollution from pulp mill emissions on the morphology, physiology, and reproductive performance of the great tit (Parus major). Great tits from a population inhabiting the vicinity of a pulp mill had significantly higher feather mercury levels and were physiologically distinct from other birds not under the direct influence of the pollution source. This distinction, due to significantly higher levels of red blood cell-glutathione peroxidase antioxidant activity, in birds from the vicinity of the pulp mill, was observed both in autumn and winter and was repeatable between years. No detectable effects were observed on breeding performance or nestling morphology and physiology. The effects of pollution in this study seem to be related to increased levels of oxidative stress.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Monitoreo del Ambiente , Passeriformes/fisiología , Reproducción/efectos de los fármacos , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/metabolismo , Animales , Atmósfera/química , Colinesterasas/sangre , Eritrocitos/enzimología , Eritrocitos/metabolismo , Plumas/metabolismo , Glutatión Peroxidasa/metabolismo , Mercurio/análisis , Mercurio/metabolismo , Mercurio/toxicidad , Estaciones del Año , Contaminantes del Suelo/análisis , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad
13.
J Oral Rehabil ; 37(4): 248-55, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20158599

RESUMEN

The purpose of this study was to evaluate the influence of age on the electromyographic activity of masticatory muscles. All volunteers were Brazilian, fully dentate (except for Group I - mixed dentition), Caucasian, aged 7-80, and divided into five groups: I (7-12 years), II (13-20 years), III (21-40 years), IV (41-60 years) and V (61-80 years). Except for Group V, which comprised nine women and eight men, all groups were equally divided with respect to gender (20 M/20 F). Surface electromyographic records of masticatory muscles were obtained at rest and during maximal voluntary contraction, right and left laterality, maximal jaw protrusion and maximal clenching in the intercuspal position. Statistically significant differences (P < 0.05) were found in all clinical conditions among the different age groups. Considerably different patterns of muscle activation were found across ages, with greater electromyographic activity in children and youth, and decreasing from adults to aged people.


Asunto(s)
Envejecimiento/fisiología , Fuerza de la Mordida , Masticación/fisiología , Músculos Masticadores/fisiología , Contracción Muscular/fisiología , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Niño , Electromiografía , Femenino , Humanos , Masculino , Desarrollo Maxilofacial , Persona de Mediana Edad , Estándares de Referencia , Adulto Joven
14.
J Appl Microbiol ; 107(5): 1669-80, 2009 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-19457040

RESUMEN

AIMS: The aim of this work was to evaluate the antiviral activities of Baccharis dracunculifolia (extract and essential oil), propolis and some isolated compounds (caffeic and cinnamic acids) against poliovirus type 1 (PV1) replication in HEp-2 cells. METHOD: Three different protocols (pre-, simultaneous and post-treatments) were used to verify the effect of addition time of the variables on PV1 replication by crystal violet method and relative viral RNA quantification by real-time PCR for analysing in which step of virus replication the variables could interfere. CONCLUSIONS: Data revealed that the B. dracunculifolia showed the best antiviral activity percentage in the simultaneous treatment, as well as lower relative viral quantification by real-time PCR. Variables might block partially the viral entry within cells, affect the steps of viral cycle replication into cells, or lead to RNA degradation before the virus entry into cells or after their release to the supernatant. SIGNIFICANCE AND IMPACT OF THE STUDY: Baccharis dracunculifolia is the most important botanical source of the south-eastern Brazilian propolis, and its potential for the development of new phytotherapeutic medicines has been investigated. Propolis is commonly used for its antimicrobial and immunomodulatory activities. Nevertheless, B. dracunculifolia and propolis effects on PV1 have not been investigated yet.


Asunto(s)
Antivirales/farmacología , Baccharis/química , Poliovirus/efectos de los fármacos , Poliovirus/crecimiento & desarrollo , Própolis/farmacología , Baccharis/fisiología , Línea Celular Tumoral/virología , Supervivencia Celular , Violeta de Genciana , Humanos , Extractos Vegetales/farmacología , Aceites de Plantas/farmacología , Reacción en Cadena de la Polimerasa/métodos , ARN Viral/análisis
15.
J Dent Res ; 98(3): 347-354, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30612505

RESUMEN

The major goal in restorative dentistry is to develop a true regenerative approach that fully recovers hydroxyapatite crystals within the caries lesion. Recently, a rationally designed self-assembling peptide P11-4 (Ace-QQRFEWEFEQQ-NH2) has been developed to enhance remineralization on initial caries lesions, yet its applicability on dentin tissues remains unclear. Thus, the present study investigated the interaction of P11-4 with the organic dentin components as well as the effect of P11-4 on the proteolytic activity, mechanical properties of the bonding interface, and nanoleakage evaluation to artificial caries-affected dentin. Surface plasmon resonance and atomic force microscopy indicated that P11-4 binds to collagen type I fibers, increasing their width from 214 ± 4 nm to 308 ± 5 nm ( P < 0.0001). P11-4 also increased the resistance of collagen type I fibers against the proteolytic activity of collagenases. The immediate treatment of artificial caries-affected dentin with P11-4 enhanced the microtensile bonding strength of the bonding interface ( P < 0.0001), reaching values close to sound dentin and decreasing the proteolytic activity at the hybrid layer; however, such effects decreased after 6 mo of water storage ( P < 0.05). In conclusion, P11-4 interacts with collagen type I, increasing the resistance of collagen fibers to proteolysis, and improves stability of the hybrid layer formed by artificial caries-affected dentin.


Asunto(s)
Recubrimiento Dental Adhesivo , Caries Dental , Dentina/metabolismo , Colágeno , Recubrimientos Dentinarios , Glicosiltransferasas , Humanos , Ensayo de Materiales , Proteolisis , Cementos de Resina , Resistencia a la Tracción
16.
Bioresour Technol ; 99(17): 8382-9, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18413285

RESUMEN

Aiming to evaluate a possible loss of soil habitat function after amendment with organic wastes, a digested sewage sludge and derived composts produced with green residues, where biologically tested in the laboratory using soil animals (Eisenia andrei and Folsomia candida) and plants (Brassica rapa and Avena sativa). Each waste was tested mimicking a field application of 6ton/ha or 12ton/ha. Avoidance tests did not reveal any impact of sludge and composts to soil biota. Germination and growth tests showed that application of composts were beneficial for both plants. Composts did not affect earthworm's mass increase or reproduction, but the highest sludge amendment revealed negative effects on both parameters. Only the amendment of composts at the highest dose originated an impairment of springtails reproductive output. We suggest that bioassays using different test species may be an additional tool to evaluate effects of amendment of organic wastes in soil. Biological tests are sensitive to pollutants at low concentrations and to interactions undetected by routine chemical analysis.


Asunto(s)
Bioensayo/métodos , Aguas del Alcantarillado , Suelo , Animales , Avena/crecimiento & desarrollo , Reacción de Prevención , Brassica rapa/crecimiento & desarrollo , Germinación , Metales Pesados/análisis , Oligoquetos/fisiología , Reproducción
17.
Artículo en Inglés | MEDLINE | ID: mdl-30509924

RESUMEN

In coastal areas, intrusion/irrigation with seawater can threaten biodiversity along with crop yields, and the leaching of salts from areas affected by these processes can increase the salinity of water bodies nearby. The aims of this study were to evaluate the effects of salinization on coastal soil ecosystems due to saline intrusion/irrigation. Terrestrial model ecosystems were used to simulate two soil salinization scenarios: (i) seawater intrusion and irrigation with distilled water and (ii) seawater intrusion and irrigation with saline water. Three sampling periods were established: T0-after acclimation period; T1-salinization effects; and T2-populations' recovery. In each sampling period, the abundance of nematodes, enchytraeids, springtails, mites and earthworms, and plant biomass were measured. Immediate negative effects on enchytraeid abundance were detected, especially at the higher level of saltwater via intrusion+irrigation. Eight weeks after the cessation of saline irrigation, the abundance of enchytraeids fully recovered, and some delayed effects were observed in earthworm abundance and plant biomass, especially at the higher soil conductivity level. The observed low capacity of soil to retain salts suggests that, particularly at high soil conductivities, nearby freshwater bodies can also be endangered. Under saline conditions similar to the ones assayed, survival of some soil communities can be threatened, leading to the loss of biodiversity.This article is part of the theme issue 'Salt in freshwaters: causes, ecological consequences and future prospects'.


Asunto(s)
Invertebrados/efectos de los fármacos , Fenómenos Fisiológicos de las Plantas/efectos de los fármacos , Salinidad , Sales (Química)/efectos adversos , Agua de Mar/efectos adversos , Suelo/química , Animales , Biomasa , Ecosistema , Invertebrados/fisiología , Modelos Biológicos
18.
Waste Manag ; 61: 582-592, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28089401

RESUMEN

A field study was established to assess the effects of a sewage sludge (SS), a mixed municipal solid waste compost (MMSWC) and a compost produced from agricultural wastes (AWC), in a Vertisol, using Lolium multiflorum L. The amendments were applied for two consecutive years: 6, 12 and 24t dry matter ha-1 for SS, and the amendment doses for MMSWC and AWC were calculated to deliver the same amount of organic matter (OM) per unit area. The amendments had significant beneficial effects on some soil properties (e.g. soil OM, NKjeldahl, extractable P and K), and on plant productivity parameters (e.g. biomass yield, chlorophyll, foliar area). For instance, soil OM increased from 0.78% to 1.71, 2.48 and 2.51%, after two consecutive years of application of 24t dry matter ha-1 of SS, MMSWC and AWC, respectively, while the plant biomass obtained increased from 7.75tha-1 to 152.41, 78.14 and 29.26tha-1, for the same amendments. On the plant, effects were more pronounced for SS than for both compost applications, a consequence of its higher capacity to provide N to the plant in a readily available form. However, after two years of application, the effects on soil properties were more noticeable for both composts, as their OM is more resistant to mineralization, which endures their beneficial effects on soil. Cadmium, Cr, Ni and Pb pseudo-total concentrations, were not affected significantly by the application of the organic wastes to soil, in all tested doses, neither their extractability by 0.01M CaCl2. On the contrary, Cu and Zn pseudo-total concentrations increased significantly in the second year of the experiment, following the application of the higher rate of MMSWC and AWC, although their extractability remained very low (<0.5% of their pseudo-total fraction). Trace elements concentrations in the aboveground plant material were lower than their maximum tolerable levels for cattle, used as an indicator of risk of their entry into the human food chain. Despite these results, it is interesting to note that the SS promoted a significant increase in the foliar concentrations of Cu, Ni and Zn that did not happen in composts application, which can be explained by the reduction of the soil pH, as a consequence of SS degradation in soil. Concluding, if this type of organic wastes were to be used in a single application, the rate could be as high as 12 or even 24tha-1, however, if they are to be applied in an annual basis, the application rates should be lowered to assure their safe application (e.g. to 6tha-1). Moreover, it is advisable to use more stable and mature organic wastes, which have longer lasting positive effects on soil characteristics.


Asunto(s)
Aguas del Alcantarillado , Contaminantes del Suelo/análisis , Suelo , Administración de Residuos/métodos , Agricultura/métodos , Lolium/crecimiento & desarrollo , Metales/análisis , Hojas de la Planta/química , Portugal , Reciclaje , Medición de Riesgo , Suelo/química , Residuos Sólidos
19.
Chemosphere ; 181: 579-588, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28467951

RESUMEN

The main goal of the present study was to evaluate the ecotoxicological effects of 1,4-naphthoquinone (1,4-NTQ), a natural-origin compound presenting nematicidal activity, that can be obtained from walnut husk, in plants and soil invertebrates, including non-target soil nematode communities. This research was part of an ongoing project that aims to develop environmentally-friendly nematicides obtained from agricultural residues. The battery of ISO tests included emergence and growth of corn (Zea mays) and rape (Brassica napus); avoidance with the earthworm Eisenia andrei and the collembolan Folsomia candida; and reproduction with the previous species plus the enchytraeid Enchytraeus crypticus. A novel soil nematode community assay was also performed. ISO tests and nematode assays were conducted using a natural uncontaminated soil that was spiked with a range of 1,4-NTQ concentrations. Toxicity of 1,4-NTQ was found for all test-species and the most sensitive were F. candida and E. andrei. After 7 days of exposure to 1,4-NTQ, nematode abundance decreased along the concentration gradient, and a partial recovery was observed after 14 days (1,4-NTQ <48 mg kg-1 soil). The number of nematode families consistently decreased in both periods. Overall, results indicate that a 1,4-NTQ concentration of <20 mg kg-1 could be environmentally safe but preliminary data suggest that it might be ineffective for the target-nematodes, root-knot nematodes, Meloidogyne spp., and root-lesion nematodes, Pratylenchus spp. In addition, if higher dosages of 1,4-NTQ bionematicide are necessary, the potential recovery of non-target organisms under real field scenarios also needs to be assessed.


Asunto(s)
Ecotoxicología , Naftoquinonas/toxicidad , Contaminantes del Suelo/toxicidad , Agricultura , Animales , Antinematodos/análisis , Antinematodos/toxicidad , Artrópodos/efectos de los fármacos , Bioensayo , Oligoquetos/efectos de los fármacos , Suelo/química , Contaminantes del Suelo/análisis , Zea mays/efectos de los fármacos
20.
Rev Port Pneumol ; 12(3): 225-40, 2006.
Artículo en Inglés, Portugués | MEDLINE | ID: mdl-16967181

RESUMEN

AIMS: This study classifies cases of traumatic diaphragmatic hernias (TDH) in patients admitted to the Intensive Care Unit (ICU) of the Coimbra University Hospitals (HUC) from 1990 to 2004. METHODS: Retrospective analysis of 34 cases of TDH, studying anatomical location, place and time of diagnosis, complementary tests aiding diagnosis, herniated organs, associated traumatism, morbidity and mortality. RESULTS: Twenty-eight male and six female patients with an average age of 40.5 years +/- 20.5, average SAPS score 38.8. Average length of stay was 19.1 +/- 13.6 days, all suffered from closed traumatism and were put on artificial ventilation. The left-side diaphragm was more frequently affected (94.1%) then the right. Diagnosis in 19 cases was made up in the first six hours following the diagnosis of traumatism, in four cases within 12 hours and in the remaining cases between 48 hours and 16 years after traumatism. In 13 patients the diagnosis was established intra-operatively. The stomach was typically one of the herniated organs. The most frequently associated lesions at the thoracic level were pulmonary contusion, haemothorax and pneumothorax, and at the abdominal level, haemoperitoneum and splenic lesion. The rates for complications and mortality were 55.8% and 11.7% respectively. CONCLUSIONS: TDH mainly occurs on the left side through closed thoraco-abdominal trauma following road traffic accidents. This group of patients, on average younger than others admitted to ICU, presents a longer average hospitalisation period, but has lower rates of mortality and lower SAPS severity scores. The most commonly herniated organ was the stomach and the most frequently encountered lesions were cranial-encephalic, splenic and pleural traumatisms. Pre-operative diagnosis of diaphragmatic injuries is difficult and a high index of clinical suspicion is needed after thoraco-abdominal trauma. This diagnosis should always be considered a possibility in cases of closed thoraco-abdominal traumas.


Asunto(s)
Hernia Diafragmática Traumática/clasificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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