RESUMO
2,4-Dichlorophenol (2,4-DCP) is considered a priority pollutant due to its high toxicity. Therefore, it is urgent to develop technologies for the disposal of this pollutant. Various remediation processes have been proposed for the elimination of 2,4-DCP in contaminated water, however, most of them involve high costs of operation and maintenance. This study aimed to determine the capacity of remediation of 2,4-DCP in water by Typha latifolia L. wild plants. For that, the tolerance, removal, accumulation and biotransformation of 2,4-DCP by T. latifolia were investigated. The plants were exposed to 2,4-DCP solutions with a concentration range from 1.5 to 300 mgL-1 for 10 days. They exhibited a reduction in chlorophyll levels and growth rate when 2,4-DCP solutions were ≥30 mgL-1 and ≥50 mgL-1, respectively. The removal of contaminant was dose-depended, being 99.7% at 1.5-3 mgL-1, 59-70% at 10-70 mgL-1 and 35-42% at 100-300 mgL-1 of 2,4-DCP in the solution. Studies indicated that 2,4-DCP was mainly accumulated in root tissue rather than in shoot tissue. Acid hydrolysis of biomass extracts suggests 2,4-DCP bioconjugates formation in root tissue as a response mechanism. Additionally, an increment in glutathione S-transferase (GST) activity could indicate a 2,4-DCP conjugation with glutathione as a detoxification mechanism of T. latifolia.
Assuntos
Biodegradação Ambiental/efeitos dos fármacos , Biotransformação/efeitos dos fármacos , Clorofenóis/toxicidade , Tolerância a Medicamentos , Recuperação e Remediação Ambiental/métodos , Raízes de Plantas/metabolismo , Typhaceae/metabolismo , Anti-Helmínticos/isolamento & purificação , Anti-Helmínticos/toxicidade , Clorofenóis/isolamento & purificação , Glutationa Transferase/metabolismo , Poluentes Químicos da ÁguaRESUMO
In 1992-1994, a disorder known as the epidemic neuropathy afflicted more than 50,000 Cubans. Three different forms of the illness were identified: epidemic optic neuropathy, peripheral neuropathy and mixed optic and peripheral neuropathy. The causes are still unknown. Skeletal muscle biopsy samples were analyzed by standard histological techniques and by biochemical assays. Elevated activities of citrate synthase, a non-respiratory-chain mitochondrial matrix enzyme, suggested possible mitochondrial proliferation in 7 of the 8 patients. Nicotinamide adenine dinucleotide phosphate (NADP(+)) levels were higher in the patients than in the controls (p = 0.04). Levels of nicotinamide adenine dinucleotide (NAD) and the reduced compounds NADH and NADPH were comparable in patients and controls. Elevations of succinate dehydrogenase and citrate synthase activities and high NADP(+) levels suggest that alterations of mitochondrial functions may be associated with this disorder.
Assuntos
Doenças Mitocondriais/enzimologia , Doenças do Nervo Óptico/enzimologia , Oxirredutases/metabolismo , Doenças do Sistema Nervoso Periférico/enzimologia , Adulto , Citrato (si)-Sintase/metabolismo , Cuba/epidemiologia , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Pessoa de Meia-Idade , Doenças Mitocondriais/epidemiologia , Músculo Esquelético/enzimologia , NADP/metabolismo , Doenças do Nervo Óptico/epidemiologia , Doenças do Sistema Nervoso Periférico/epidemiologia , Succinato Citocromo c Oxirredutase/metabolismo , Succinato Desidrogenase/metabolismoRESUMO
INTRODUCTION: The mitochondria, subcellular organelles which possess their own DNA (mtDNA), produce most of the energy, in the form of ATP, which is necessary for life. This mtDNA may have diverse molecular defects which have been associated with a great variety of clinical syndromes. Deletions in mtDNA are one of the common mutations in patients with mitochondrial myopathies, which in the great majority present with the common symptom of progressive external ophthalmoplegia. In this study we report our findings in eight Cuban families with suspected mitochondrial disease. OBJECTIVES: To characterize these patients from the molecular point of view, which would allow a preliminary understanding of the behavior of these deletions in Cuban patients. PATIENTS AND METHODS: We studied nine patients from eight Cuban families in whom mitochondrial encephalomyopathy was suspected. We analyzed the presence of ragged red fibres, the enzymatic activity of the mitochondrial respiratory chain and detection of mtDNA mutations. We used the technique of restriction length polymorphism analysis for detection of deletions. RESULTS: Histochemical studies showed the presence of COX negative ragged red fibres in seven of the patients studied. The enzymatic activity of the mitochondrial respiratory chain was normal in all the patients. We detected four patients with single deletions of mtDNA, and one with multiple deletions and of the patients had the A3243G mutation. CONCLUSIONS: With the methods used we were able to determine the presence of a mitochondrial disorder in seven of the eight families studied and deletions of mtDNA were detected as the cause of the illness in five. The disorder was always associated with progressive external ophthalmoplegia and COX negative ragged red fibres.
Assuntos
DNA Mitocondrial/genética , Oftalmoplegia Externa Progressiva Crônica/epidemiologia , Oftalmoplegia Externa Progressiva Crônica/genética , Adolescente , Adulto , Southern Blotting , Cuba/epidemiologia , Análise Mutacional de DNA , Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Feminino , Deleção de Genes , Humanos , Imuno-Histoquímica , Masculino , Oftalmoplegia Externa Progressiva Crônica/enzimologia , Mutação Puntual/genética , Polimorfismo de Fragmento de RestriçãoRESUMO
INTRODUCTION: Leber's hereditary optic neuropathy (LHON) is a mitochondrial disorder, confirmed at a molecular level 10 years ago. This had permitted better understanding of the condition. Since 1998, the Instituto de Neurología y Neurocirugía has used these techniques for the study of mutations which are considered to be the origin of the disorder. PATIENTS AND METHODS: We describe the characteristics of 14 cases from 10 families with LHON and the molecular confirmation found between 1994 and 1998 in the Instituto de Neurología Neurocirugía de Cuba. We also review the few cases seen in the previous 18 years. These were from only two families. They were diagnosed on clinical grounds and in view of maternal inheritance. RESULTS AND CONCLUSIONS: In 80% of the families in which the presence of primary mutations was investigated there was A117789, and in 20% A3460G. The average age of appearance was 28 years. The ages of onset were within the limits of 11 years and 48 years. There were 43% women. Two cases were considered to be sporadic. The clinical features corresponded to those described in such cases, with severe visual defects, central scotomas, very reduced colour vision and severely altered visual evoked potentials, with normal diffuse light and pattern electroretinograms. An improvement in visual acuity of 0.2 was seen in two cases. Microangiopathy, described as characteristic of the early stages of this disorder was detected in five cases, in at least one eye. The others had different degrees of optic atrophy. Two generations of one complete family, all with mutation 3460, were studied. In several families with this mutation alterations were found in the colour vision test of Farnsworth Munsell Hue 100 and also microangiospathy of the retina.
Assuntos
Atrofias Ópticas Hereditárias/diagnóstico , Atrofias Ópticas Hereditárias/genética , Transtornos da Visão/diagnóstico , Adolescente , Adulto , Instituições de Assistência Ambulatorial , Criança , Cuba , Análise Mutacional de DNA , DNA Mitocondrial/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurologia , Oftalmologia , Atrofias Ópticas Hereditárias/complicações , Mutação Puntual/genética , Polimorfismo Genético/genética , Sistema de Registros , Estudos Retrospectivos , Índice de Gravidade de Doença , Transtornos da Visão/etiologia , Acuidade Visual/fisiologiaRESUMO
INTRODUCTION: This century, the greatest epidemic affecting the nervous system was notified in Cuba seven years ago. At the present time the epidemic continues although to a lesser extent. The clinical findings of the illness were mainly bilateral optic neuropathy sometimes accompanied by other symptoms and peripheral neuropathy. The similarity of the optic form of the illness with Leber's hereditary optic neuropathy, and their common risk factors, were obvious from the beginning. PATIENTS AND METHODS: Statistics from the national reference department of neuro-ophthalmology of the Instituto de Neurologia de Cuba were reviewed. From these it was evident that the number of cases of Leber's hereditary optic neuropathy had increased in recent years, coinciding with the period of epidemic and endemic Cuban neuropathy. Many of these patients had previously been diagnosed as having epidemic optic neuropathy. RESULTS: We describe the characteristics of a group of these patients and discuss the differences and possible relationship between the two conditions. In the case of epidemic optic neuropathy, there is strikingly simultaneous loss of vision, less visual changes with much smaller cecocentral scotomas, loss of ganglion fibres of the retina around the papillomacular bundle, a good response to multivitamin treatment, and increased frequency of association with peripheral sensory neuropathy. CONCLUSION: This analysis reinforces the hypothesis that many patients with Leber's hereditary optic neuropathy, which started at the time of the epidemic, were incorrectly classified as suffering from this, and also perhaps their condition worsened due to the toxic nutritional features common to both conditions.
Assuntos
Atrofias Ópticas Hereditárias , Adulto , Cuba/epidemiologia , Análise Mutacional de DNA , DNA Mitocondrial/genética , Surtos de Doenças , Feminino , Humanos , Masculino , Atrofias Ópticas Hereditárias/epidemiologia , Mutação Puntual/genéticaRESUMO
The purpose of this paper was to observe changes occurred on the surface of some amalgams commonly found in the national market in order to evaluate tarnishing, darkening and corrosion on polished and non-polished surfaces. The method used was alternate immersion in bidestilled water, and 50% acetic acid, 14.5% lactic acid. A control, for comparative purposes, was not submitted to immersion but left in normal environmental conditions.