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1.
Front Pediatr ; 12: 1319885, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38283630

RESUMEN

Congenital erythrocytosis recognizes heterogeneous genetic basis and despite the use of NGS technologies, more than 50% of cases are still classified as idiopathic. Herein, we describe the case of a 3-year-old boy with a rare metabolic disorder due to SLC30A10 bi-allelic mutations and characterized by hypermanganesemia, congenital erythrocytosis and neurodegeneration, also known as hypermanganesemia with dystonia 1 (HMNDYT1). The patient was treated with iron supplementation and chelation therapy with CaNa2EDTA, resulting in a significative reduction of blood manganese levels and erythrocytosis indexes. Although it couldn't be excluded that the patient's developmental impairment was part of the phenotypic spectrum of the disease, after three months from starting treatment no characteristic extrapyramidal sign was detectable. Our findings suggest the importance of assessing serum manganese levels in patients with unexplained polycythemia and increased liver enzymes. Moreover, we highlight the importance of extended genetic testing as a powerful diagnostic tool to uncover rare genetic forms of congenital erythrocytosis. In the described patient, identifying the molecular cause of erythrocytosis has proven essential for proper clinical management and access to therapeutic options.

2.
Front Oncol ; 11: 752192, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34692534

RESUMEN

Iron chelation therapy (ICT) has become a mainstay in heavily transfused hematological patients, with the aim to reduce iron overload (IOL) and prevent organ damage. This therapeutic approach is already widely used in thalassemic patients and in low-risk Myelodysplastic Syndrome (MDS) patients. More recently, ICT has been proposed for high-risk MDS, especially when an allogeneic bone marrow transplantation has been planned. Furthermore, other hematological and hereditary disorders, characterized by considerable transfusion support to manage anemia, could benefit from this therapy. Meanwhile, data accumulated on how iron toxicity could exacerbate anemia and other clinical comorbidities due to oxidative stress radical oxygen species (ROS) mediated by free iron species. Taking all into consideration, together with the availability of approved oral iron chelators, we envision a larger use of ICT in the near future. The aim of this review is to better identify those non-thalassemic patients who can benefit from ICT and give practical tips for management of this therapeutic strategy.

3.
Front Oncol ; 10: 604143, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33409153

RESUMEN

The combined derangements in mitochondria network, function and dynamics can affect metabolism and ATP production, redox homeostasis and apoptosis triggering, contributing to cancer development in many different complex ways. In hematological malignancies, there is a strong relationship between cellular metabolism, mitochondrial bioenergetics, interconnections with supportive microenvironment and drug resistance. Lymphoma and chronic lymphocytic leukemia cells, e.g., adapt to intrinsic oxidative stress by increasing mitochondrial biogenesis. In other hematological disorders such as myeloma, on the contrary, bioenergetics changes, associated to increased mitochondrial fitness, derive from the adaptive response to drug-induced stress. In the bone marrow niche, a reverse Warburg effect has been recently described, consisting in metabolic changes occurring in stromal cells in the attempt to metabolically support adjacent cancer cells. Moreover, a physiological dynamic, based on mitochondria transfer, between tumor cells and their supporting stromal microenvironment has been described to sustain oxidative stress associated to proteostasis maintenance in multiple myeloma and leukemia. Increased mitochondrial biogenesis of tumor cells associated to acquisition of new mitochondria transferred by mesenchymal stromal cells results in augmented ATP production through increased oxidative phosphorylation (OX-PHOS), higher drug resistance, and resurgence after treatment. Accordingly, targeting mitochondrial biogenesis, electron transfer, mitochondrial DNA replication, or mitochondrial fatty acid transport increases therapy efficacy. In this review, we summarize selected examples of the mitochondrial derangements in hematological malignancies, which provide metabolic adaptation and apoptosis resistance, also supported by the crosstalk with tumor microenvironment. This field promises a rational design to improve target-therapy including the metabolic phenotype.

4.
Blood Transfus ; 17(3): 196-199, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30865583

RESUMEN

BACKGROUND: Iron deficiency is the most common nutritional deficiency in advanced cancer patients and causes anaemia. Iron deficiency anaemia treatment (i.e. intravenous or oral iron administration) has been demonstrated to be effective but is often associated with adverse reactions. Micronised microencapsulated ferric pyrophosphate (MMFP) is a recently developed formulation characterised by a higher intestinal bioavailability due to the small particle size distribution at nanometer level. The aim of this study was to evaluate the efficacy of an oral administration of 30 mg of MMFP associated with 80 mg of ascorbic acid in advanced cancer patients with hyposideraemia. MATERIALS AND METHODS: This was an observational prospective cohort study (10 months) conducted on 42 adult patients with advanced cancer and serum iron levels lower than 60 µg/dL. All patients received one capsule/day for 30 days of a supplement containing 30 mg of MMFP and 80 mg of ascorbic acid. At enrolment (T0) and at 30 days (T1) patients were subjected to blood sampling for evaluation of serum iron, ferritinaemia and blood count. In addition, any undesirable effects reported by patients were evaluated. RESULTS: MMFP treatment increased sideraemia from 36.1±8.37 µg/dL to 73.22±28.60 µg/dL, haemoglobin from 10.43±1.09 g/dL to 11.52±1.90 g/dL, and ferritinaemia from 42.10±16.90 ng/mL to 123.33±55.79 ng/mL. No adverse effects were noted from the use of MMFP supplementation. DISCUSSION: The supplementation of 30 mg/d of MMFP in combination with 80 mg/d of ascorbic acid in advanced cancer patients with hyposideraemia led to a significant increase in sideraemia and ferritinaemia. Moreover, in some of the patients whose serum iron level did not increase, an increase in haemoglobin was observed.


Asunto(s)
Anemia Ferropénica , Difosfatos/administración & dosificación , Hierro/administración & dosificación , Neoplasias , Administración Intravenosa , Administración Oral , Anciano , Anemia Ferropénica/sangre , Anemia Ferropénica/tratamiento farmacológico , Femenino , Humanos , Hierro/sangre , Deficiencias de Hierro , Masculino , Persona de Mediana Edad , Neoplasias/sangre , Neoplasias/tratamiento farmacológico , Proyectos Piloto , Estudios Prospectivos
5.
Int J Mol Sci ; 20(3)2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-30708965

RESUMEN

Iron toxicity is associated with organ injury and has been reported in various clinical conditions, such as hemochromatosis, thalassemia major, and myelodysplastic syndromes. Therefore, iron chelation therapy represents a pivotal therapy for these patients during their lifetime. The aim of the present study was to assess the iron chelating properties of α-lipoic acid (ALA) and how such an effect impacts on iron overload mediated toxicity. Human mesenchymal stem cells (HS-5) and animals (zebrafish, n = 10 for each group) were treated for 24 h with ferric ammonium citrate (FAC, 120 µg/mL) in the presence or absence of ALA (20 µg/mL). Oxidative stress was evaluated by reduced glutathione content, reactive oxygen species formation, mitochondrial dysfunction, and gene expression of heme oxygenase-1b and mitochondrial superoxide dismutase; organ injury, iron accumulation, and autophagy were measured by microscopical, cytofluorimetric analyses, and inductively coupled plasma‒optical mission Spectrometer (ICP-OES). Our results showed that FAC results in a significant increase of tissue iron accumulation, oxidative stress, and autophagy and such detrimental effects were reversed by ALA treatment. In conclusion, ALA possesses excellent iron chelating properties that may be exploited in a clinical setting for organ preservation, as well as exhibiting a good safety profile and low cost for the national health system.


Asunto(s)
Compuestos Férricos/efectos adversos , Quelantes del Hierro/administración & dosificación , Sobrecarga de Hierro/tratamiento farmacológico , Compuestos de Amonio Cuaternario/efectos adversos , Ácido Tióctico/administración & dosificación , Animales , Autofagia/efectos de los fármacos , Línea Celular , Modelos Animales de Enfermedad , Glutatión/metabolismo , Hemo-Oxigenasa 1/genética , Humanos , Quelantes del Hierro/farmacología , Sobrecarga de Hierro/inducido químicamente , Sobrecarga de Hierro/genética , Sobrecarga de Hierro/metabolismo , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/genética , Ácido Tióctico/farmacología , Pez Cebra
6.
Blood Rev ; 32(6): 473-479, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-29699840

RESUMEN

Excess iron can be extremely toxic for the body and may cause organ damage in the absence of iron chelation therapy. Preclinical studies on the role of free iron on bone marrow function have shown that iron toxicity leads to the accumulation of reactive oxygen species, affects the expression of genes coding for proteins that regulate hematopoiesis, and disrupts hematopoiesis. These effects could be partially attenuated by iron-chelation treatment with deferasirox, suggesting iron toxicity may have a negative impact on the hematopoietic microenvironment. Iron toxicity is of concern in transfusion-dependent patients. Importantly, iron chelation with deferasirox can cause the loss of transfusion dependency and may induce hematological responses, although the mechanisms through which deferasirox exerts this action are currently unknown. This review will focus on the possible mechanisms of toxicity of free iron at the bone marrow level and in the bone marrow microenvironment.


Asunto(s)
Médula Ósea/metabolismo , Susceptibilidad a Enfermedades , Hierro/metabolismo , Anemia Aplásica/complicaciones , Anemia Aplásica/etiología , Anemia Aplásica/metabolismo , Anemia Aplásica/terapia , Animales , Células de la Médula Ósea/metabolismo , Microambiente Celular , Células Madre Hematopoyéticas/metabolismo , Humanos , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/tratamiento farmacológico , Sobrecarga de Hierro/etiología , Sobrecarga de Hierro/metabolismo , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/etiología , Síndromes Mielodisplásicos/metabolismo , Síndromes Mielodisplásicos/terapia , Mielofibrosis Primaria/complicaciones , Mielofibrosis Primaria/etiología , Mielofibrosis Primaria/metabolismo , Mielofibrosis Primaria/terapia
7.
Molecules ; 21(4): 395, 2016 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-27023497

RESUMEN

The methanol extracts of the aerial part of four ethnomedicinal plants of Mediterranean region, two non-seed vascular plants, Equisetum hyemale L. and Phyllitis scolopendrium (L.) Newman, and two Spermatophyta, Juniperus communis L. (J. communis) and Cotinus coggygria Scop. (C. coggygria), were screened against four human cells lines (A549, MCF7, TK6 and U937). Only the extracts of J. communis and C. coggygria showed marked cytotoxic effects, affecting both cell morphology and growth. A dose-dependent effect of these two extracts was also observed on the cell cycle distribution. Incubation of all the cell lines in a medium containing J. communis extract determined a remarkable accumulation of cells in the G2/M phase, whereas the C. coggygria extract induced a significant increase in the percentage of G1 cells. The novelty of our findings stands on the observation that the two extracts, consistently, elicited coherent effects on the cell cycle in four cell lines, independently from their phenotype, as two of them have epithelial origin and grow adherent and two are lymphoblastoid and grow in suspension. Even the expression profiles of several proteins regulating cell cycle progression and cell death were affected by both extracts. LC-MS investigation of methanol extract of C. coggygria led to the identification of twelve flavonoids (compounds 1-11, 19) and eight polyphenols derivatives (12-18, 20), while in J. communis extract, eight flavonoids (21-28), a α-ionone glycoside (29) and a lignin (30) were found. Although many of these compounds have interesting individual biological activities, their natural blends seem to exert specific effects on the proliferation of cell lines either growing adherent or in suspension, suggesting potential use in fighting cancer.


Asunto(s)
Proliferación Celular/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Extractos Vegetales/farmacología , Polifenoles/farmacología , Anacardiaceae/química , Puntos de Control de la Fase G2 del Ciclo Celular/efectos de los fármacos , Humanos , Células MCF-7 , Medicina Tradicional , Neoplasias/genética , Extractos Vegetales/química , Polifenoles/análisis , Polifenoles/química , Semillas/química
8.
Int J Mol Sci ; 16(9): 20417-30, 2015 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-26343645

RESUMEN

Although photodynamic therapy (PDT), a therapeutic approach that involves a photosensitizer, light and O2, has been principally considered for the treatment of specific types of cancers, other applications exist, including the treatment of infections. Unfortunately, PDT does not always guarantee full success since it exerts lethal effects only in cells that have taken up a sufficient amount of photosensitizer and have been exposed to adequate light doses, conditions that are not always achieved. Based on our previous experience on the combination PDT/chemotherapy, we have explored the possibility of fighting bacteria that commonly crowd infected surfaces by combining PDT with an antibiotic, which normally does not harm the strain at low concentrations. To this purpose, we employed 5-aminolevulinic acid (5-ALA), a pro-drug that, once absorbed by proliferating bacteria, is converted into the natural photosensitizer Protoporphyrin IX (PpIX), followed by Gentamicin. Photoactivation generates reactive oxygen species (ROS) which damage or kill the cell, while Gentamicin, even at low doses, ends the work. Our experiments, in combination, have been highly successful against biofilms produced by several Gram positive bacteria (i.e., Staphylococcus aureus, Staphylococcus epidermidis, etc.). This original approach points to potentially new and wide applications in the therapy of infections of superficial wounds and sores.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Farmacorresistencia Bacteriana , Luz , Fotoquimioterapia , Fármacos Fotosensibilizantes/farmacología , Gentamicinas/farmacología , Pruebas de Sensibilidad Microbiana , Microscopía Confocal
9.
Biomed Res Int ; 2015: 286817, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25767805

RESUMEN

Introduction. Plant extracts may be suitable alternative treatments for caries. Aims. To investigate the in vitro and in vivo antimicrobial effects of Plantago lanceolata herbal tea (from flowers and leaves) on cariogenic bacteria and to identify the major constituents of P. lanceolata plant. Materials and Methods. The MIC and MBC against cariogenic bacteria were determined for P. lanceolata tea. Subsequently, a controlled random clinical study was conducted. Group A was instructed to rinse with a P. lanceolata mouth rinse, and Group B received a placebo mouth rinse for seven days. The salivary colonisation by streptococci and lactobacilli was investigated prior to treatment and on the fourth and seventh days. Finally, the P. lanceolata tea was analysed for its polyphenolic content, and major phenolics were identified. Results and Discussion. P. lanceolata teas demonstrate good in vitro antimicrobial activity. The in vivo test showed that Group A subjects presented a significant decrease in streptococci compared to Group B. The phytochemical analysis revealed that flavonoids, coumarins, lipids, cinnamic acids, lignans, and phenolic compounds are present in P. lanceolata infusions. Conclusions. P. lanceolata extract could represent a natural anticariogenic agent via an antimicrobial effect and might be useful as an ancillary measure to control the proliferation of cariogenic flora.


Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Lactobacillus/efectos de los fármacos , Fenoles/farmacología , Plantago/química , Saliva/microbiología , Streptococcus/efectos de los fármacos , Adolescente , Línea Celular Tumoral , Niño , Femenino , Flavonoides/química , Flavonoides/farmacología , Humanos , Masculino , Fenoles/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Hojas de la Planta/química , Células U937
10.
Artículo en Inglés | MEDLINE | ID: mdl-24302963

RESUMEN

This study aims to evaluate the activity of Italian vulnerary plants against the most important oral pathogenic bacteria. This estimate was accomplished through a fivefold process: (a) a review of ethnobotanical and microbiological data concerning the Italian vulnerary plants; (b) the development of a scoring system to rank the plants; (c) the comparative assessment of microbiological properties; (d) the assessment of potential cytotoxic effects on keratinocyte-like cells and gingival fibroblasts in culture by XTT cell viability assay; (e) clinical evaluation of the most suitable plant extract as antibacterial agent in a home-made mouthwash. The study assays hexane (H), ethanol (E), and water (W) extracts from 72 plants. The agar diffusion method was used to evaluate the activity against Streptococcus mutans, Streptococcus sobrinus, Lactobacillus casei, and Actinomyces viscosus. Twenty-two plants showed appreciable activity. The extracts showing the strongest antibacterial power were those from Cotinus coggygria Scop., Equisetum hyemale L., Helichrysum litoreum Guss, Juniperus communis L., and Phyllitis scolopendrium (L.) Newman subsp. scolopendrium. The potential cytotoxic effect of these extracts was assessed. On the basis of these observations, a mouth-rinse containing the ethanolic extract of H. litoreum has been tested in vivo, resulting in reduction of the salivary concentration of S. mutans.

11.
Curr Pharm Des ; 19(15): 2765-70, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23092325

RESUMEN

Identification of imatinib mesylate as a potent inhibitor of the Abl kinase and the subsequent findings that this compound displays growth inhibitory and pro-apoptotic effects in Bcr-Abl+ cells, has deeply conditioned CML treatment. Unfortunately the initial striking efficacy of this drug has been overshadowed by the development of clinical resistance. A wide variety of molecular mechanisms can underlie such resistance mechanisms. In the recent years, heme oxygenase-1 (HO-1) expression has been reported as an important protective endogenous mechanism against physical, chemical and biological stress and this cytoprotective role has already been demonstrated for several solid tumors and acute leukemias. The aim of the present study was to investigate the effect of HO-1 expression on cell proliferation and apoptosis in chronic myeloid leukemia cells, K562 and LAMA-84 cell lines following imatinib treatment. Cells were incubated for 24h with Imatinib (1 µM) alone or in combination with Hemin (10µM), an inducer of HO-1. In addition, cells were also treated with HO byproducts, bilirubin and carbon monoxide (CO), or with a protease inhibitor (Ed64) to inhibit HO-1 nuclear translocation. Pharmacological induction of HO-1 was able to overcome the effect of imatinib. The cytoprotective effect of HO-1 was further confirmed after silencing HO-1 by siRNA. Interestingly, neither bilirubin nor CO was able to protect cells from Imatinib-induced toxicity. By contrast, the protective effect of HO-1 was mitigated by the addition of E64d, preventing HO-1 nuclear translocation. Finally, imatinib was able to increase the formation of cellular reactive oxygen species (ROS) and this effect was reversed by HO-1 induction or the addition of N-acetylcisteine (NAC). In conclusion, the protective effect of HO-1 on imatinib-induced cytotoxicity does not involve its enzymatic byproducts, but rather the nuclear translocation of HO-1 following proteolytic cleavage.


Asunto(s)
Antineoplásicos/uso terapéutico , Benzamidas/uso terapéutico , Núcleo Celular/metabolismo , Hemo-Oxigenasa 1/metabolismo , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Piperazinas/uso terapéutico , Pirimidinas/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Resistencia a Antineoplásicos , Silenciador del Gen , Hemo-Oxigenasa 1/genética , Humanos , Mesilato de Imatinib , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Especies Reactivas de Oxígeno/metabolismo
12.
Clin Cancer Res ; 14(6): 1877-87, 2008 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-18347191

RESUMEN

PURPOSE: Premature or stress-induced senescence is a major cellular response to chemotherapy in solid tumors and contributes to successful treatment. However, senescent tumor cells are resistant to apoptosis and may also reenter the cell cycle. We set out to find a means to specifically induce senescent tumor cells to undergo cell death and not to reenter the cell cycle that may have general application in cancer therapy. EXPERIMENTAL DESIGN: We investigated the mechanisms regulating cell survival in drug-induced senescent tumor cells. Using immunofluorescence and flow cytometry-based techniques, we established the status of the ataxia telangiectasia mutated (ATM) signaling pathway in these cells. We assayed the requirement of ATM signaling and p21(CIP1) expression for survival in premature senescent tumor cells using pharmacologic inhibitors and antisense oligonucleotides. RESULTS: The ATM/ATR (ATM- and Rad3-related) signaling pathway was found to be constitutively active in drug-induced senescent tumor cells. We found that blocking ATM/ATR signaling with pharmacologic inhibitors, including the novel ATM inhibitors KU55933 and CGK733, induced senescent breast, lung, and colon carcinoma cells to undergo cell death. We show that the mechanism of action of this effect is directly via p21(CIP1), which acts downstream of ATM. This is in contrast to the effects of ATM inhibitors on normal, untransformed senescent cells. CONCLUSIONS: Blocking ATM and/or p21(CIP1) following initial treatment with a low dose of senescence-inducing chemotherapy is a potentially less toxic and highly specific treatment for carcinomas.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Carcinoma/tratamiento farmacológico , Proteínas de Ciclo Celular/fisiología , Senescencia Celular/efectos de los fármacos , Neoplasias del Colon/tratamiento farmacológico , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , Proteínas de Unión al ADN/fisiología , Neoplasias Pulmonares/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/fisiología , Proteínas Supresoras de Tumor/fisiología , Proteínas de la Ataxia Telangiectasia Mutada , Bencenoacetamidas/farmacología , Neoplasias de la Mama/fisiopatología , Carcinoma/fisiopatología , Ciclo Celular/efectos de los fármacos , Proteínas de Ciclo Celular/antagonistas & inhibidores , Supervivencia Celular/efectos de los fármacos , Senescencia Celular/fisiología , Neoplasias del Colon/fisiopatología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Daño del ADN/efectos de los fármacos , Proteínas de Unión al ADN/antagonistas & inhibidores , Evaluación Preclínica de Medicamentos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Células HCT116 , Humanos , Neoplasias Pulmonares/fisiopatología , Morfolinas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Pironas/farmacología , Tiourea/análogos & derivados , Tiourea/farmacología , Células Tumorales Cultivadas , Proteínas Supresoras de Tumor/antagonistas & inhibidores
13.
Expert Opin Drug Deliv ; 4(2): 131-48, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17335411

RESUMEN

Photodynamic therapy (PDT) combines a drug (a photosensitiser or photosensitising agent) with a specific type of light to kill cancer cells. It is a minimally invasive treatment, with great potential in malignant disease and premalignant conditions. Following the administration of the photosensitiser, light of the appropriate wavelength is directed onto the abnormal tissue where the drug has preferentially accumulated. Upon light activation, the photosensitiser transfers its excess energy to molecular oxygen to produce an excited state (i.e., the highly reactive singlet oxygen) that causes oxidative damage at the site of its generation. The energy transfer occurs either directly to oxygen or through an indirect mechanism that requires the formation of intermediate radical species. Many photosensitisers have been developed, but only a few have been approved for therapy in humans. Basic research in model systems (animals, cell lines) has unravelled some fundamental cellular processes involved in the cell response to PDT. The exploitation of relevant molecular observations, the discovery and introduction of new sensitisers, the progress in the light delivery systems and light dosimetry are all concurring to the increase of PDT therapeutic efficacy. However, this field has not yet reached maturity. This review briefly analyses the relevant properties of most photosensitisers and their field of application. Special attention is dedicated to the effects observed in model cancer systems; speculation and suggestions of possible future research directions are also offered.


Asunto(s)
Neoplasias/tratamiento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotosensibilizantes/uso terapéutico , Animales , Evaluación Preclínica de Medicamentos , Quimioterapia Combinada , Humanos , Rayos Láser , Luz , Oxígeno Singlete
14.
Sci Total Environ ; 341(1-3): 265-79, 2005 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-15833257

RESUMEN

The activity of a range of enzymes related to the cycling of the main biologically important nutrients C, N, P and S was investigated in cultivated and non-cultivated soils from various parts of Europe. Two agricultural sites from North Italy under continuous corn (Zea mays L.) with and without organic fertilization were compared. Two other agricultural sites from South Italy under hazel (Corylus avellana L.) never flooded or repeatedly flooded over by uncontrolled urban and industrial wastes were investigated. The non-cultivated soils were from Middle and South Europe with different pollution history such as no-pollution and pollution with organic contaminants, which is phenanthrene and other polycyclic aromatic hydrocarbons (PAHs). Agricultural soils showed significant differences in some of physical-chemical properties (i.e. organic C, total and labile phosphate contents, available Ca and Mg) between the two sites studied. Enzyme activities of hazel sites periodically flooded by wastes were mainly higher than in the hazel sites never flooded. Sites under many years of continuous corn showed dehydrogenase, invertase, arylsulphatase and beta-glucosidase activities generally lower than the soils under hazel either flooded or not by wastes. As compared to agricultural soils, non-cultivated soils heavily or moderately polluted by organic contaminants displayed much lower values or complete absence of enzymatic activities. Dissimilar, contradictory correlations between soil enzyme activities and the majority of soil properties were observed separately in the two groups of soils. When the whole set of enzyme activities and soil properties were considered, all significant correlations found separately for the groups of soils were lost. The overall results seem to confirm that no direct cause-effect relationships can be derived between the changes of a soil in response to a given factor and both the variations of the activity and the behaviour of the enzymes in soil.


Asunto(s)
Agricultura , Enzimas/análisis , Contaminantes del Suelo/análisis , Suelo/análisis , Calcio/análisis , Carbono/análisis , Cobre/análisis , Corylus , Monitoreo del Ambiente , Europa (Continente) , Magnesio/análisis , Petróleo , Fósforo/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Zea mays
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