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1.
Surf Coat Technol ; 409: 126873, 2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33814662

RESUMEN

The widespread of viral airborne diseases is becoming a critical problem for human health and safety, not only for the common cold and flu, but also considering more serious infection as the current pandemic COVID-19. Even if the current heating, ventilating and air conditioning (HVAC) systems limit the disease transmission by air, the air filters are susceptible to microbial colonization. In addition, viruses spread via droplets (aerosol) produced by direct or indirect contact with infected people. In this context, the necessity of an efficient HVAC system, able to capture and inactivate viruses- and bacteria-rich aerosols, thus preserving a safe indoor air environment and protecting people, is of enormous importance. The aim of this work is the assessment of the antiviral properties of a silver nanoclusters/silica composite coating deposited via co-sputtering technique on glass, on metallic fibre-based air filters as well as on cotton textiles. The selected human respiratory viruses are: respiratory syncytial virus (RSV), the human rhinovirus (HRV) and the influenza virus type A (FluVA). The coated air filters show that the nanostructured coating develops a strong virucidal activity against RSV and FluVA, but not against the HRV.

2.
Arch Soc Esp Oftalmol ; 98(4): 213-219, 2023 Apr.
Artículo en Español | MEDLINE | ID: mdl-36713825

RESUMEN

Background and objective: Digital evolution represents an opportunity for ophthalmology to adapt to new care models. This study aimed to find out how the pandemic has modified the clinical practice and training activities of the ophthalmologist specialized in ocular surface, as well as to analyze emerging trends and needs. Materials and methods: This study was carried out through an online survey. A committee of 3 specialists developed a questionnaire of 25 questions structured in: 1) Participant profile; 2) Impact of the pandemic on patient management and professional activities; 3) Trends and needs. Results: Sixty-eight clinical ophthalmologists participated. There was a high degree of agreement (90%) that the pandemic has delayed ophthalmological follow-up visits and diagnosis. The participants agreed that the frequency of patients with dry eye disease (75%), stye/chalazion (62%) and blepharitis (60%) has increased. According to 28%, remote monitoring of pathologies such as dry eye, glaucoma, diabetes, conjunctivitis, hyposphagmas, styes, etc., will be common, especially in the young population. This will be especially relevant in chronic or mild pathologies of the ocular surface, and in the follow-up of patients after cataract and diabetic retinopathy interventions. Conclusions: During the pandemic, an increase in the incidence of certain ocular surface diseases has been perceived. The telematic follow-up of chronic or mild pathologies of the ocular surface entails the need to provide specific training for both the patient and the healthcare professional, in addition to screening and referral protocols that would optimize the flow of care.

3.
Arch Soc Esp Oftalmol (Engl Ed) ; 98(4): 213-219, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36878286

RESUMEN

INTRODUCTION AND OBJECTIVE: Digital evolution represents an opportunity for ophthalmology to adapt to new care models. This study aimed to find out how the pandemic has modified the clinical practice and training activities of the ophthalmologist specialised in ocular surface, as well as to analyse emerging trends and needs. MATERIALS AND METHODS: This study was carried out through an online survey. A committee of 3 specialists developed a questionnaire of 25 questions structured in: 1) Participant profile; 2) Impact of the pandemic on patient management and professional activities; 3) Trends and needs. RESULTS: 68 clinical ophthalmologists participated. There was a high degree of agreement (90%) that the pandemic has delayed ophthalmological follow-up visits and diagnosis. The participants agreed that the frequency of patients with dry eye disease (75%), stye/chalazion (62%) and blepharitis (60%) has increased. According to 28%, remote monitoring of pathologies such as dry eye, glaucoma, diabetes, conjunctivitis, hyposphagmas, styes, etc., will be common, especially in the young population. This will be especially relevant in chronic or mild pathologies of the ocular surface, and in the follow-up of patients after cataract and diabetic retinopathy interventions. CONCLUSIONS: During the pandemic, an increase in the incidence of certain ocular surface diseases has been perceived. The telematic follow-up of chronic or mild pathologies of the ocular surface entails the need to provide specific training for both the patient and the healthcare professional, in addition to screening and referral protocols that would optimise the flow of care.


Asunto(s)
Blefaritis , COVID-19 , Retinopatía Diabética , Glaucoma , Oftalmología , Humanos , Oftalmología/métodos , Glaucoma/diagnóstico
4.
Environ Pollut ; 268(Pt A): 115806, 2021 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-33126033

RESUMEN

The occurrence of human pathogenic viruses in aquatic ecosystems and, in particular, in internal water bodies (i.e., river, lakes, groundwater, drinking water reservoirs, recreational water utilities, and wastewater), raises concerns regarding the related impacts on environment and human health, especially in relation to the possibility of human exposure and waterborne infections. This paper reviews the current state of knowledge regarding severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) presence and persistence in human excreta, wastewaters, sewage sludge as well as in natural water bodies, and the possible implications for water services in terms of fecal transmission, public health, and workers' risk. Furthermore, the impacts related to the adopted containment and emergency management measures on household water consumptions are also discussed, together with the potential use of wastewater-based epidemiology (WBE) assessment as a monitoring and early warning tool, to be applied in case of infectious disease outbreaks. The knowledge and tools summarized in this paper provide a basic information reference, supporting decisions makers in the definition of suitable measures able to pursue an efficient water and wastewater management and a reduction of health risks. Furthermore, research questions are provided, in order to direct technical and public health communities towards a sustainable water service management in the event of a SARS-CoV-2 re-emergence, as well as a future deadly outbreak or pandemic.


Asunto(s)
COVID-19 , SARS-CoV-2 , Ecosistema , Humanos , Pandemias , Aguas Residuales , Agua
5.
J Microsc ; 237(3): 333-6, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20500391

RESUMEN

Nano-composite layers of Au nano-crystallites embedded in amorphous silica matrix were obtained by a radio-frequency co-sputtering technique. Glass or single crystal silicon wafers were chosen as substrates. After deposition, the layers were heat treated at 900 degrees C for 60 min. Microstructure of the layers was investigated using a TECNAI G(2) FEG SuperTwin (200 kV) transmission electron microscope. Thin foils were cut using a focused ion beam Quanta 3D. The investigations confirmed that the applied process allowed obtaining nano-composite layers containing spherical Au crystallites of average size of approximately 3 nm embedded in an amorphous silica matrix. Some of the nano-crystallites were twinned. The layers were heat treated in subsequent step and rise of the crystallite average size up to 5.5 nm confirming activation of diffusion processes was seen. Presence of irregularly shaped Au crystallites in the latter layers indicates incomplete sintering due to short annealing time.

6.
Toxicol Lett ; 287: 92-99, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29421334

RESUMEN

We tested cadmium (Cd2+) effects on porcine IPEC-J2 cells, which represent an in vitro model of the interaction between intestinal cells and both infectious and non-infectious stressors. Accordingly, we investigated the effects of low (2 µM) to moderate (20 µM) concentrations of Cd2+, in terms of pro-inflammatory gene expression and protein release, as well as of infectivity in a Salmonella typhimurium penetration model. Our data showed a significant (P < .001) increase of intracellular Cd2+ after 3, 6 and 24 h of exposure with respect to levels at 1 h. These data showed the ability of IPEC-J2 to absorb Cd2+ as a function of both time and concentration. Also, the absorption of this heavy metal was related to a significant modulation of important pro-inflammatory messengers. In particular, down-regulation of IL-8 was associated with a significant decrease of Salmonella typhimurium ability to penetrate into IPEC-J2 cells, in agreement with a previous study in which an anti-IL 8 antibody could significantly inhibit Salmonella penetration into the same cells (Razzuoli et al., 2017). This finding demonstrates the ability of Cd2+ to affect the outcome of an important host-pathogen relationship. In conclusion, our study highlighted the ability of an environmental pollutant like Cd2+ to modulate innate immune responses in terms of chemokine release and gene expression, and susceptibility to microbial infections.


Asunto(s)
Compuestos de Cadmio/toxicidad , Enterocitos/efectos de los fármacos , Yeyuno/efectos de los fármacos , Animales , Compuestos de Cadmio/metabolismo , Línea Celular , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Enterocitos/inmunología , Enterocitos/metabolismo , Enterocitos/microbiología , Interacciones Huésped-Patógeno , Inmunidad Innata/efectos de los fármacos , Mediadores de Inflamación/metabolismo , Interleucina-8/genética , Interleucina-8/metabolismo , Absorción Intestinal , Yeyuno/inmunología , Yeyuno/metabolismo , Yeyuno/microbiología , Salmonella typhimurium/efectos de los fármacos , Salmonella typhimurium/patogenicidad , Sus scrofa , Factores de Tiempo
8.
Opt Express ; 13(18): 6878-86, 2005 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-19498706

RESUMEN

The diffraction efficiency of gratings written in ternary SnO2:SiO2:Na2O bulk glasses rises dramatically with time after the occultation of the cw 244nm light used to write the thick hologram. This self-induced behavior lasts for several hours and ultimately leads to refractive index changes as high as 3 10-3.

9.
Tissue Cell ; 37(3): 247-55, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15899507

RESUMEN

During embryogenesis the bone tissue of craniomandibular joint (CMJ) is formed through two pathways: intramembranous ossification and endochondral ossification. The development process is under the control of regulatory factors. The osteoprotegerin (OPG) and the receptor activator of nuclear factor (NF)-kappaB ligand are key regulators of osteoclastogenesis. The aim of this study is the localization of OPG and RANKL mRNA and protein in the foetal CMJ by immunohistochemistry (IHC) and in situ hybridization (ISH). The main results were: OPG and RANKL mRNA and protein were co-localized in the same cell types; OPG and RANKL were specially immunolocated in osteogenic cells; immunolabeling was often seen in the nucleus and cytoplasm of otherwise negative hypertrophic chondrocytes; IHC and ISH labeling decreased from proliferative to hypertrophic chondrocytes; early osteocytes showed dual protein expression and some of the mature osteocytes were ISH-negative; periosteal osteoclasts and chondroclasts were mostly stained by IHC and variably labeled by ISH; the new bone matrix and trabecular borders showed intense immunolabeling. The co-expression of OPG and RANKL in the same bone cell types confirms their strictly coupled action in the regulation of bone metabolism in the CMJ development and their extracellular presence in the new bone matrix and trabecular borders suggests a local regulatory role.


Asunto(s)
Proteínas Portadoras/biosíntesis , Glicoproteínas/biosíntesis , Glicoproteínas de Membrana/biosíntesis , Osteogénesis , Receptores Citoplasmáticos y Nucleares/biosíntesis , Receptores del Factor de Necrosis Tumoral/biosíntesis , Articulación Temporomandibular/metabolismo , Proteínas Portadoras/genética , Cartílago Articular/embriología , Cartílago Articular/metabolismo , Glicoproteínas/genética , Humanos , Inmunohistoquímica , Hibridación in Situ , Glicoproteínas de Membrana/genética , Osteoprotegerina , Ligando RANK , ARN Mensajero/biosíntesis , Receptor Activador del Factor Nuclear kappa-B , Receptores Citoplasmáticos y Nucleares/genética , Receptores del Factor de Necrosis Tumoral/genética , Articulación Temporomandibular/embriología
10.
Biomaterials ; 22(9): 987-94, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11311018

RESUMEN

An in vitro evaluation of a biomedical device, which combines the mechanical properties of zirconia substrates with the bioactivity of two different glass layers (AP40 and RKKP), was performed. In this work, data on different kinds of analysis were reported both on as-sintered zirconia samples and on RKKP- and AP40-coated zirconia substrates. Structure, composition and morphology of the apatite layer growth on the coated samples after 30 days of soaking in an acellular simulated body fluid, serum protein adsorption, fibroblasts and human osteoblast-like cells adhesion, growth, morphology and biochemical aspects were studied. Results of soaking test in SBF, revealed the growth of an apatite layer on the surface of the glass-coated samples. Proteins adsorbed to the materials were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis and results evidenced that the two glass-coated materials bound a higher amount of total protein than did the zirconia substrate. Fibroblasts and osteoblast-like cells cultured on RKKP- and AP40-coated zirconia showed a higher proliferation rate, leading to confluent cultures with higher cell density and a generally better expression of osteoblast alkaline phosphatase activity in comparison with zirconia substrate. In conclusion, our results indicate that the surface chemical characteristics of the two glass coatings AP40 and RKKP, with no great differences between them, substantially enhance zirconia integration with bone cells at least in vitro. This effect may be of significance in the stability of glass-coated zirconia orthopaedic and dental implants.


Asunto(s)
Materiales Biocompatibles , Vidrio , Circonio , Adsorción , Línea Celular , Electroforesis en Gel de Poliacrilamida , Humanos , Técnicas In Vitro , Proteínas/química
11.
Biomaterials ; 21(8): 765-73, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10721745

RESUMEN

In order to combine the mechanical properties of a high-strength inert ceramic (yttria-stabilised zirconia, ZrO2-3%Y2O3, defined as zirconia in the text) with the specific properties of bioactive materials, some zirconia samples were coated by two bioactive phosphosilicate glasses and glass-ceramics: RKKP and AP40. Coatings of about 200-300 microm thickness were prepared by a simple and low-cost firing method. They were characterised by optical and scanning electron microscopy (SEM) and compositional analysis (EDS). The adhesion of the coatings on zirconia was tested by shear tests. Vickers indentations at the coating/zirconia interface were performed in order to observe the crack propagation path. The reactivity of glasses and glass-ceramics coatings towards a simulated body fluid (SBF), having the same ion concentration as that of human plasma, was evaluated and compared to that of the bulk glass and glass-ceramics, by examining the morphology of the reaction layer formed on the surface of the coated zirconia after one month of soaking in the SBF at 37 degrees C.


Asunto(s)
Materiales Biocompatibles , Circonio , Líquidos Corporales , Cerámica , Vidrio , Humanos , Técnicas In Vitro , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Propiedades de Superficie
12.
Histol Histopathol ; 15(2): 499-502, 2000 04.
Artículo en Inglés | MEDLINE | ID: mdl-10809371

RESUMEN

The mechanisms of cariogenesis in occlusal fissures remain elusive because of limited information about fissure structure and wall mineralization. The purpose of the present study was to determine the correlation between morphological patterns in occlusal fissures in human premolars and quantitative histochemical patterns of mineralization in the walls of these formations. We used scanning electron microscopy and quantitative X-ray microanalysis with the peak-to-local background ratio method and microcrystalline calcium salts as standards. We distinguished three morphological patterns of fissures in scanning electron microscopic images. The wall of the fissures was less mineralized than the control enamel in all three types of fissures. Because the fissure walls are hypomineralized, we suggest that practicing dentists should take into account the degree of mineralization when they are preparing the fissures for the application of sealant.


Asunto(s)
Diente Premolar/patología , Fisuras Dentales/patología , Diente Premolar/metabolismo , Calcio/metabolismo , Fisuras Dentales/metabolismo , Humanos
13.
Histol Histopathol ; 13(1): 109-13, 1998 01.
Artículo en Inglés | MEDLINE | ID: mdl-9476640

RESUMEN

Sample preparation of dental tissues for quantitative electron microprobe analysis has not been critically examined because of the highly mineralized nature of these structures. The present study was designed to establish the most suitable method for the electron probe quantitative determination of calcium in human permanent enamel and dentine while preserving the morphological features. Comparisons of quantitative data obtained with air-drying and freeze-drying methods showed that calcium in enamel was more accurately measured in specimens prepared with cryopreservation and freeze-drying. No significant differences between the methods tested were found in dentine although cryopreservation and freeze-drying yielded less statistical variability. Moreover this approach did not modify morphological features of interest. We recommend this combination of processing techniques for human permanent teeth not only because it was found the most accurate and least variable in determining calcium concentration, but also because of its potential usefulness in studies of alterations in tooth mineralization.


Asunto(s)
Esmalte Dental/química , Dentina/química , Calcio/análisis , Criopreservación , Microanálisis por Sonda Electrónica/métodos , Liofilización , Humanos , Fijación del Tejido/métodos
14.
Histol Histopathol ; 16(3): 827-32, 2001 07.
Artículo en Inglés | MEDLINE | ID: mdl-11510973

RESUMEN

Teeth fragments from members of a family clinically and genetically diagnosed as having amelogenesis imperfecta were studied by scanning electron microscopy and X-ray microprobe analysis to establish the morphological patterns and the quantitative concentration of calcium in the enamel of anterior (canine, incisor) and posterior (premolar and molar) teeth. The prism patterns in the enamel of teeth from both regions were parallel or irregularly decussate, with occasional filamentous prisms accompanied by small, irregularly rounded formations. Prismless enamel showed the R- and P-type patterns. Calcium levels in enamel of amelogenesis imperfecta and control teeth differed significantly between anterior and posterior teeth, indicating that the factors that influence normal mineralization in different regions of the dental arch are not altered in the process of amelogenesis imperfecta.


Asunto(s)
Amelogénesis Imperfecta/patología , Calcinosis/patología , Esmalte Dental/ultraestructura , Amelogénesis Imperfecta/genética , Amelogénesis Imperfecta/metabolismo , Calcinosis/metabolismo , Calcio/análisis , Estudios de Casos y Controles , Esmalte Dental/química , Microanálisis por Sonda Electrónica , Humanos , Microscopía Electrónica de Rastreo
15.
Toxicology ; 123(1-2): 135-42, 1997 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-9347928

RESUMEN

Changes in the cytochrome P450 monooxygenase system were investigated in HepG2 cells treated for 24 h with 1.25, 2.5, 5, 10 and 20 microg/ml of carbendazim (MBC) and n-butylisocyanate (BIC), the principal benomyl metabolites. The results show that n-butylisocyanate leads to a decrease in both ethoxyresorufin deethylase (P4501A1) (EROD) and ethoxycoumarin deethylase (P4502B) (ECOD), whereas MBC has no effect on EROD and increases ECOD. The decrease in ECOD and EROD activities after BIC treatment can be attributed to the detrimental action of this substance. The MBC-induced increase in ethoxycoumarin can be considered an enzyme-specific inductive phenomenon. This hypothesis was confirmed by Western immunoblot analysis and treatment with actinomycin D 8 x 10(-4) microM: the first showed an increase in P4502B isoenzyme content and the second evidence of a partial block of the increase in ECOD activity induced by MBC. Given these results, MBC and BIC seem to be the metabolites responsible for the double opposite action of their parent compound benomyl. Data deriving from an equimolar mixture of the two metabolites suggest that benomyl activity on some cytochrome P450 isoenzymes is the result of a balance between the action of the single metabolites (Radice et al., 1996).


Asunto(s)
Benomilo/farmacología , Bencimidazoles/farmacología , Carbamatos , Sistema Enzimático del Citocromo P-450/metabolismo , Fungicidas Industriales/farmacología , Isocianatos/farmacología , Hígado/metabolismo , 7-Alcoxicumarina O-Dealquilasa/metabolismo , Bencimidazoles/metabolismo , Bencimidazoles/toxicidad , Western Blotting , Línea Celular , Citocromo P-450 CYP1A1/metabolismo , Fungicidas Industriales/metabolismo , Fungicidas Industriales/toxicidad , Humanos , Técnicas In Vitro , Isocianatos/metabolismo , Isocianatos/toxicidad , Hígado/citología , Hígado/enzimología
16.
Toxicology ; 129(2-3): 183-91, 1998 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-9772096

RESUMEN

It is well known that the dicarboximide fungicides, vinclozolin and iprodione, induce lipid peroxidation by means of oxygen activation in fungi, but their action on mammalian cells is not yet clear. We therefore investigated the effect of 1- and 24-h treatments with vinclozolin at concentrations of 25, 50, 100 microg/ml and iprodione at concentration of 62.5, 125, 250 microg/ml on malonaldehyde and free radical production and on reduced glutathione levels in the human HepG2 hepatoma cell line. The concentrations were chosen on the basis of neutral red cytotoxicity assays. One-hour treatment with the different concentrations of either vinclozolin or iprodione increased both malonaldehyde and free radical content, and decreased reduced glutathione levels, whereas 24-h treatment decreased malonaldehyde content and free radical production, and increased reduced glutathione concentration. These results suggest that the mammalian cells respond to the initial oxidative damage caused by the two dicarboximide fungicides by means of a characteristic adaptative phenomenon within 24 h. This hypothesis is supported by the antagonized effects caused by treatment with the two dicarboximide fungicides and buthionine sulfoximine 0.5 mM, a specific and irreversible inhibitor of reduced glutathione synthesis. The data confirm that the two dicarboximide fungicides maintain their specific action in mammalian cells, although this action is masked by adaptation.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Fungicidas Industriales/toxicidad , Hidantoínas , Oxazoles/toxicidad , Estrés Oxidativo , Adaptación Fisiológica , Aminoimidazol Carboxamida/toxicidad , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Glutamato-Cisteína Ligasa/biosíntesis , Glutatión/biosíntesis , Humanos , Peroxidación de Lípido/efectos de los fármacos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Células Tumorales Cultivadas
17.
Clin Exp Rheumatol ; 15 Suppl 17: S83-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9266138

RESUMEN

According to the most recent literature, few antirheumatic drugs can claim disease-controlling properties over the anatomical joint damage in rheumatoid arthritis (RA). A small number of studies have favored one or another of the available agents, in particular parenteral gold salts, sulphasalazine and methotrexate, but the evidence regarding their efficacy is not convincing when analysed using methodological criteria known to be important in evaluating radiologic evidence of joint damage. The radiologic results in long-standing RA patients have shown that CsA may be of benefit in reducing disease progression. Data from the second year of a clinical trial designed to compare the disease-controlling, anti-rheumatic properties of CsA with those of conventional disease-modifying anti-rheumatic drugs (DMARDs) in early RA support the hypothesis that CsA may be useful in delaying the appearance of new joint erosion.


Asunto(s)
Antirreumáticos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Ciclosporina/uso terapéutico , Articulaciones/efectos de los fármacos , Adulto , Artritis Reumatoide/diagnóstico por imagen , Artritis Reumatoide/fisiopatología , Artrografía , Ensayos Clínicos como Asunto , Humanos , Articulaciones/patología , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
18.
Toxicol In Vitro ; 16(4): 475-80, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12110288

RESUMEN

It has been shown that procymidone, a dicarboximide fungicide, alters sexual differentiation in vivo and in vitro. The aim of this study was to evaluate the estrogenic activity of this fungicide using the synthesis of vitellogenin (Vtg) in rainbow trout hepatocyte as a biological marker. The cells were treated for 24 h with procymidone 150 microM, using 17beta-estradiol 20 microM as a positive control. The doses were chosen on the basis of cell viability (Neutral Red and MTT tests) and solubility. The results show that procymidone leads to a qualitative and quantitative increase in Vtg synthesis. In Western immonoblots, the 170 and 30 kDa bands, which respectively correspond to the monomeric form of Vtg and posvitine, were brighter in cells treated with procymidone and 17beta-estradiol than those corresponding to the negative controls (cells treated for 24 h with DMSO 0.1% alone); ELISA showed that the cells treated with the fungicide and 17beta-estradiol had a 48 and 76%, respectively, higher Vtg concentration than the negative controls (P<0.01). Western blotting also revealed the induction of HSP27 (27 KDa), which further confirms the estrogenic acitivity of procymidone as it is known that the 3' region of HSP27/28 containing the gene mRNAs is induced by estrogen treatment. Procymidone increased also the production of both HSP70 protein (70 KDa) and free oxygen radicals. This last finding is in agreement with the toxic mechanism of dicarboximide fungicides. It can therefore be presumed that the estrogenic activity of procymidone in primary cultured trout hepatocytes is related to oxidative damage which, as many other studies have shown, can increase the levels of estrogens such as 17beta-estradiol, and thus increase Vtg synthesis


Asunto(s)
Compuestos Bicíclicos con Puentes/efectos adversos , Fungicidas Industriales/efectos adversos , Hepatocitos/efectos de los fármacos , Estrés Oxidativo , Vitelogeninas/biosíntesis , Animales , Biomarcadores/análisis , Western Blotting , Técnicas de Cultivo de Célula , Supervivencia Celular , Estradiol/farmacología , Femenino , Radicales Libres , Proteínas de Choque Térmico , Hepatocitos/patología , Masculino , Receptores de Estrógenos/efectos de los fármacos , Diferenciación Sexual
19.
Toxicol In Vitro ; 16(4): 365-74, 2002 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12110274

RESUMEN

The rainbow trout cytochrome P4501A gene subfamily consists of two members, CYP1A1 and CYP1A3, which are induced by polycyclic aromatic hydrocarbons (PAHs). In this study, we investigated the induction of cytochrome P4501A3 in the rainbow trout (Onchorhynchus mykiss) D-11 cell line after 3-methylcholanthrene (3MC) exposure by generating chimeric constructs in which a 2.3 kb fragment or portion of the 5'-flanking region of the trout cytochrome CYP1A3 gene was fused to the firefly luciferase (Luc) gene. The constructs were then transiently transfected into the trout D-11 cells and their transcriptional activity measured by luciferase assay after treatment with different 3MC concentrations. Maximal induction following exposure to 2 microM 3MC was 2.2-fold after 72 h. Deletion of the region specifying the 5' untranslated region (5'UTR) of the mRNA encoding the CYP1A3 gene increased unstimulated luciferase activity but also led to a loss of response to 3MC treatment. This finding suggests that the region specifying the 5'UTR contains a negative element that is also involved in the transcriptional response to 3MC.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/farmacología , Oncorhynchus mykiss/fisiología , Animales , Hidrocarburo de Aril Hidroxilasas/genética , Secuencia de Bases , Carcinógenos/efectos adversos , Línea Celular , Fibroblastos/patología , Luciferasas/farmacología , Metilcolantreno/efectos adversos , Datos de Secuencia Molecular , ARN Mensajero , Transfección
20.
Aquat Toxicol ; 54(1-2): 51-8, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11451425

RESUMEN

As is known from literature, iprodione, a dicarboximide fungicide, has a highly specific action, with a capacity to cause oxidative damage through production of free oxygen radicals (ROS), but it does not appear to be species selective. Since this substance is able to diffuse in water, evaluation of its capacity to induce oxidative damage in an aquatic organism such as the rainbow trout (Oncorhynchus mykiss) was considered of particular interest. A study was, therefore, undertaken to investigate the effect of iprodione on free radicals (ROS) and malondialdehyde (MDA) production, reduced glutathione (GSH) content and catalase activity (CAT), in primary cultured trout hepatocytes, following treatment with 0.2, 0.3 and 0.4 mM concentrations for a 24-h period. The iprodione 0.3 and 0.4 mM concentrations increased both ROS and MDA production and decreased GSH content and CAT activity. These results suggest that iprodione is able to produce oxidative damage in primary cultured fish hepatocytes, thus confirming that its action is specific, but not species selective. It is also well known that ROS production in fungi is due to interaction with the flavin enzyme NADPH cytochrome c reductase to the extent that the normal electron flow from NADPH to cytochrome c is blocked. In contrast, we observed that, in primary cultured trout hepatocytes, iprodione appears to have no effect on NADPH cytochrome c reductase activity. It is, therefore, possible to presume that the mechanism of oxidative damage in trout hepatocytes differs from that observed in fungi. Moreover, our experiments also demonstrate that iprodione is able to induce "in vitro" CYP1A1, leading to the conclusion that the production of ROS is due to this phenomenon.


Asunto(s)
Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/toxicidad , Fungicidas Industriales/toxicidad , Hepatocitos/efectos de los fármacos , Hidantoínas , Animales , Catalasa/metabolismo , Células Cultivadas , Citocromo P-450 CYP1A1/metabolismo , Relación Dosis-Respuesta a Droga , Glutatión/análisis , Hepatocitos/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Oncorhynchus mykiss , Especies Reactivas de Oxígeno
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