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1.
Clin Rheumatol ; 39(1): 27-36, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31111363

RESUMO

INTRODUCTION: DeSScipher is the first European multicentre study on management of systemic sclerosis (SSc), and its observational trial 1 (OT1) evaluated the efficacy of different drugs for digital ulcer (DU) prevention and healing. The aim of this study was to assess current use of vasoactive/vasodilating agents for SSc-related DU in the expert centres by analysing the baseline data of the DeSScipher OT1. METHOD: Baseline characteristics of patients enrolled in the OT1 and data regarding DU were analysed. RESULTS: The most commonly used drugs, in both patients with and without DU, were calcium channel blockers (CCBs) (71.6%), followed by intravenous iloprost (20.8%), endothelin receptor antagonists (ERAs) (20.4%) and phosphodiesterase 5 (PDE-5) inhibitors (16.5%). Of patients, 32.6% with DU and 12.8% without DU received two drugs (p < 0.001), while 11.5% with DU and 1.9% without DU were treated with a combination of three or more agents (p < 0.001). Sixty-five percent of the patients with recurrent DU were treated with bosentan and/or sildenafil. However, 64 out of 277 patients with current DU (23.1%) and 101 (23.6%) patients with recurrent DU were on CCBs alone. CONCLUSIONS: Our study shows that CCBs are still the most commonly used agents for DU management in SSc. The proportion of patients on combination therapy was low, even in patients with recurrent DU: almost one out of four patients with current and recurrent DU was on CCBs alone. Prospective analysis is planned to investigate the efficacy of different drugs/drug combinations on DU healing and prevention. Key Points • The analysis of DeSScipher, the first European multicentre study on management of SSc, has shown that the most commonly used vasoactive/vasodilating drugs for DU were CCBs, followed by intravenous Iloprost, ERAs and PDE-5 inhibitors. • More than half of the patients with recurrent DU received bosentan and/or sildenafil. • However, the proportion of patients on combination therapy of more than one vasoactive/vasodilating drug was low and almost one out of four patients with current and recurrent DU was on CCBs alone.


Assuntos
Dedos/patologia , Escleroderma Sistêmico/tratamento farmacológico , Úlcera Cutânea/tratamento farmacológico , Vasodilatadores/uso terapêutico , Adulto , Idoso , Bosentana/uso terapêutico , Quimioterapia Combinada , Europa (Continente) , Feminino , Humanos , Iloprosta/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escleroderma Sistêmico/diagnóstico , Citrato de Sildenafila/uso terapêutico , Úlcera Cutânea/diagnóstico , Resultado do Tratamento , Cicatrização/efeitos dos fármacos
2.
Arthritis Res Ther ; 21(1): 35, 2019 01 24.
Artigo em Inglês | MEDLINE | ID: mdl-30678703

RESUMO

BACKGROUND: A consensus on digital ulcer (DU) definition in systemic sclerosis (SSc) has been recently reached (Suliman et al., J Scleroderma Relat Disord 2:115-20, 2017), while for their evaluation, classification and categorisation, it is still missing. The aims of this study were to identify a set of essential items for digital ulcer (DU) evaluation, to assess if the existing DU classification was useful and feasible in clinical practice and to investigate if the new categorisation was preferred to the simple distinction of DU in recurrent and not recurrent, in patients with systemic sclerosis (SSc). METHODS: DeSScipher is the largest European multicentre study on SSc. It consists of five observational trials (OTs), and one of them, OT1, is focused on DU management. The DeSScipher OT1 items on DU that reached ≥ 60% of completion rate were administered to EUSTAR (European Scleroderma Trials and Research group) centres via online survey. Questions about feasibility and usefulness of the existing DU classification (DU due to digital pitting scars, to loss of tissue, derived from calcinosis and gangrene) and newly proposed categorisation (episodic, recurrent and chronic) were also asked. RESULTS: A total of 84/148 (56.8%) EUSTAR centres completed the questionnaire. DeSScipher items scored by ≥ 70% of the participants as essential and feasible for DU evaluation were the number of DU defined as a loss of tissue (level of agreement 92%), recurrent DU (84%) and number of new DU (74%). For 65% of the centres, the proposed classification of DU was considered useful and feasible in clinical practice. Moreover, 80% of the centres preferred the categorisation of DU in episodic, recurrent and chronic to simple distinction in recurrent/not recurrent DU. CONCLUSIONS: For clinical practice, EUSTAR centres identified only three essential items for DU evaluation and considered the proposed classification and categorisation as useful and feasible. The set of items needs to be validated while further implementation of DU classification and categorisation is warranted. TRIAL REGISTRATION: Observational trial on DU (OT1) is one of the five trials of the DeSScipher project (ClinicalTrials.gov; OT1 Identifier: NCT01836263 , posted on April 19, 2013).


Assuntos
Dedos , Escleroderma Sistêmico/tratamento farmacológico , Úlcera Cutânea/tratamento farmacológico , Adulto , Bosentana/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Quimioterapia Combinada , União Europeia , Feminino , Humanos , Iloprosta/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Escleroderma Sistêmico/classificação , Escleroderma Sistêmico/diagnóstico , Citrato de Sildenafila/uso terapêutico , Úlcera Cutânea/classificação , Úlcera Cutânea/diagnóstico , Inquéritos e Questionários
3.
Scand J Rheumatol ; 48(1): 42-51, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30039730

RESUMO

OBJECTIVE: The aim of this study was to analyse differences in clinical presentation in patients with early (< 3 years' duration) systemic sclerosis (SSc), comparing three age groups according to disease subsets. METHOD: Cross-sectional analysis of the prospective EULAR Scleroderma Trials and Research database (EUSTAR) was performed. Patients fulfilling preliminary American College of Rheumatology 1980 classification criteria for SSc, with < 3 years from the first non-Raynaud's SSc symptom at first entry, were selected. Patients with < 3 years from the first SSc symptom, including Raynaud's phenomenon, were also analysed. SSc-related variables, including antibodies, SSc subsets, and organ involvement, were examined. Age was categorized into ≤ 30, 31-59, and ≥ 60 years. We performed descriptive and bivariate analyses. RESULTS: The study included 1027 patients: 90% Caucasian, 80% women, and 40% with diffuse disease. In early stages of SSc, younger patients had significantly more anti-Scl-70 antibodies and diffuse disease. With increasing age, we observed more elevation of estimated pulmonary systolic pressure on echocardiography (5%, 13%, and 30%, respectively, in the three age groups), cardiac conduction blocks (6%, 6%, and 15%), and left ventricular diastolic dysfunction (4%, 12%, and 27%). The results were similar for 650 patients with < 3 years from first SSc symptom, including Raynaud's. CONCLUSION: In early stages of SSc, older patients showed data indicating more severe disease with greater cardiac involvement. The diffuse subset was more frequent in the younger subgroup. The identification of such differences may help in selecting appropriate management for individual patients in clinical practice.


Assuntos
Sistema de Registros , Escleroderma Sistêmico/epidemiologia , Adulto , Distribuição por Idade , Fatores Etários , Idade de Início , Estudos Transversais , Bases de Dados Factuais , Europa (Continente)/epidemiologia , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Escleroderma Sistêmico/diagnóstico , Distribuição por Sexo
4.
Clin Exp Immunol ; 181(1): 100-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25847615

RESUMO

Human leucocyte antigen (HLA)-G has a tolerogenic function and could play a role in the pathogenesis of immune-mediated diseases, including systemic sclerosis (SSc). The aim of this study was to evaluate HLA-G serum expression (sHLA-G) and the HLA-G gene 14 base pairs (bp) insertion/deletion (del(-)/del(+)) polymorphism in patients with Ssc, to search for possible associations with clinical and laboratory variables. sHLA-G was measured by enzyme-linked immunosorbent assay (ELISA) in sera from 77 patients with SSc and 32 healthy donors (HD); the 14 bp del(-)/del(+) polymorphism was evaluated by polymerase chain reaction (PCR) amplification of peripheral blood mononuclear cells (PBMC) genomic DNA. Receiver operating characteristics (ROC) analysis identified the HLA-G cut-off that best discriminated dichotomized clinical and serological variables, that was subsequently employed to subdivide SSc patients into HLA-G high (HLA-G(+)) and low (HLA-G(-)) profile groups. sHLA-G were not statistically different between SSc patients and HD, nor between distinct SSc autoantibody subsets. Subdividing SSc patients by HLA-G positivity or negativity yielded significant differences for the modified Rodnan skin score (mRss) (P = 0.032), 'general' (P = 0.031) and 'kidney' (P = 0.028) Medsger severity scores (MSS) and disease activity index, and especially Δ heart/lung (P = 0.005). A worse 'general' MSS (P = 0.002) and Δ heart/lung (P = 0.011) were more frequent in the low sHLA-G group. These two variables and mRss were associated with sHLA-G levels at logistic regression analysis. Treatment had no influence on sHLA-G. Moreover, a higher frequency of scleredema was detected in the del(+)/del(+) than the del(-)/del(+) group (P = 0.04). These data suggest modulatory effects of sHLA-G on SSc. Prospective studies are needed to investigate a role in predicting the disease course.


Assuntos
Antígenos HLA-G/sangue , Antígenos HLA-G/genética , Leucócitos Mononucleares/imunologia , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/imunologia , Feminino , Frequência do Gene , Antígenos HLA-G/imunologia , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos
6.
Reumatismo ; 62(3): 202-9, 2010.
Artigo em Italiano | MEDLINE | ID: mdl-21052567

RESUMO

OBJECTIVE: To investigate survival in Italian systemic sclerosis (SSc) patients from a tertiary center, reporting death causes. MATERIALS AND METHODS: We analyzed the charts of 251 SSc patients prospectively enrolled in our Rheumatology Unit from 2000 to 2008. Baseline characteristics were recorded. In 2008 the vital status and the causes of death were assessed. Overall and subgroup survival were analyzed by the Kaplan-Meier method and the log-rank test. RESULTS: In 2008, 82% of patients were alive, 8% were known to have died and 10% were lost to follow-up. Overall 5- and 8-year survival were 94.8% and 77.1%, respectively. Patients with an age greater than the median value of the cohort (χ²=4.4; p=0.036), diffuse cutaneous SSc (χ²=3.9; p=0.048), digital ulcers (χ²=6; p=0.015), articular (χ²=5.3; p=0.021), lung (χ²=5.6; p=0.018) and heart involvement (χ²=9.3; p=0.002) had a poorer survival than patients without these features. The majority of SSc-related deaths (60%) were secondary to interstitial lung disease and heart involvement (both 33.3%); 50% of non-SSc-related deaths were due to cancer. CONCLUSIONS: Our study reports an improvement in survival of Italian SSc patients during the last decade with respect to the previous ones. Moreover, a reduction in deaths from renal involvement and an increase in deaths from interstitial lung disease were recorded in Italian SSc patients. Our data are consistent with those from recent survival studies carried out on SSc patients from other geographic areas.


Assuntos
Causas de Morte , Escleroderma Sistêmico/epidemiologia , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Comorbidade , Feminino , Cardiopatias/mortalidade , Departamentos Hospitalares , Hospitais Universitários/estatística & dados numéricos , Humanos , Itália/epidemiologia , Nefropatias/mortalidade , Doenças Pulmonares Intersticiais/mortalidade , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Reumatologia , Fatores de Risco , Escleroderma Sistêmico/mortalidade , Análise de Sobrevida , Adulto Jovem
7.
Scand J Rheumatol ; 39(6): 485-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20604675

RESUMO

OBJECTIVE: To investigate the prevalence of clinical and subclinical atherosclerosis in systemic sclerosis (SSc) patients and its associated features. METHODS: Fifty unselected SSc patients and 41 controls, matched for sex and age, were investigated for previous cardiovascular events, cardiovascular risk factors, and ultrasonographic features of subclinical atherosclerosis in the carotid arteries, that is intima-media thickness (IMT) > 0.9 mm or plaques. SSc patients were also investigated for disease features and previous treatment. Finally, blood samples were randomly selected from 27 patients and 18 controls to evaluate concentrations of amino-terminal propeptide of type III procollagen (PIIINP), transforming growth factor (TGF)-ß, hepatocyte growth factor (HGF), soluble interleukin-2 receptor (sIL-2R), IL-13, E-selectin, intercellular adhesion molecule (ICAM)-1, plasminogen activator inhibitor (PAI)-1, tissue plasminogen activator (t-PA), D-dimer, and prothrombin fragments (F1+2). RESULTS: Previous cardiovascular events were recorded in three SSc patients and no controls (p > 0.05). Mean IMT (0.613 ± 0.240 vs. 0.654 ± 0.173 mm) did not differ between patients and controls (p > 0.05), but subclinical atherosclerosis was detected in 14/50 SSc patients and 4/41 controls (p = 0.036). At multiple logistic regression analysis, mean IMT was correlated with older age [p = 0.006; odds ratio (OR) 1.276, 95% confidence interval (CI) 1.043-1.516] and a higher cumulative corticosteroid intake (p = 0.017; OR 1.155, 95% CI 1.027-1.300). No correlation was found with any soluble marker of disease activity and of coagulation/fibrinolysis system activation. CONCLUSION: Our study confirms an increased prevalence of subclinical atherosclerosis in SSc patients and demonstrates a hitherto unknown association with corticosteroid cumulative dosage.


Assuntos
Corticosteroides/efeitos adversos , Aterosclerose/epidemiologia , Prednisolona/efeitos adversos , Escleroderma Sistêmico/tratamento farmacológico , Escleroderma Sistêmico/epidemiologia , Corticosteroides/administração & dosagem , Adulto , Aterosclerose/sangue , Aterosclerose/induzido quimicamente , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/induzido quimicamente , Doenças das Artérias Carótidas/epidemiologia , Colágeno Tipo III/sangue , Selectina E/sangue , Feminino , Produtos de Degradação da Fibrina e do Fibrinogênio/análise , Fator de Crescimento de Hepatócito/sangue , Humanos , Imunossupressores/uso terapêutico , Molécula 1 de Adesão Intercelular/sangue , Interleucina-13/sangue , Masculino , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Inibidor 1 de Ativador de Plasminogênio/sangue , Prednisolona/administração & dosagem , Prevalência , Precursores de Proteínas/sangue , Protrombina , Receptores de Interleucina-2/sangue , Escleroderma Sistêmico/sangue , Ativador de Plasminogênio Tecidual/sangue , Fatores de Crescimento Transformadores/sangue , Túnica Íntima/patologia , Adulto Jovem
8.
Ann Rheum Dis ; 68(3): 408-11, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18930992

RESUMO

OBJECTIVE: To investigate the possible implication of SDF1-3' polymorphism in systemic sclerosis (SSc) susceptibility or clinical phenotype, or both. METHODS: 150 patients with SSc and 150 controls were enrolled. Skin involvement, autoantibodies, interstitial lung disease, pulmonary arterial hypertension (PAH), scleroderma renal crisis, past and/or current skin ulcers were assessed. Genotyping was performed by PCR-RFLP. RESULTS: Genotype distribution and allele frequency were similar in SSc and controls. SDF1-3'A allele and SDF1-3'GA/AA genotype frequencies were significantly higher in SSc-PAH than in SSc-non-PAH (33.3% vs 18.3%, p = 0.01) and in SSc with skin ulcers than in SSc without ulcers (27.3% vs 16.9%, p = 0.03). The SDF1-3'A allele influenced the predisposition to SSc-related PAH (OR = 2.52, 95% CI 1.11 to 5.69, p = 0.02) and skin ulcers (OR = 2.31, 95% CI 1.18 to 4.52, p = 0.01). After adjustment for age and gender, the SDF1-3'A allele remained a susceptibility factor for the SSc-related vascular manifestations (PAH: OR = 2.37, 95% CI 1.04 to 5.42, p = 0.04; ulcers: OR = 2.33, 95% CI 1.78 to 4.62, p = 0.01). CONCLUSION: The SDF1-3'A allele is significantly associated with microvascular involvement in SSc.


Assuntos
Quimiocina CXCL12/genética , Escleroderma Sistêmico/genética , Úlcera Cutânea/etiologia , Adulto , Idoso , Autoanticorpos/sangue , Estudos de Coortes , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Masculino , Microvasos , Pessoa de Meia-Idade , Fenótipo , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Escleroderma Sistêmico/complicações , Escleroderma Sistêmico/imunologia , Úlcera Cutânea/genética
9.
Reumatismo ; 60(4): 268-73, 2008.
Artigo em Italiano | MEDLINE | ID: mdl-19132151

RESUMO

BACKGROUND: Hypocomplementemia has been detected in about 15% of unselected series of SSc patients. It constitutes one of the 10 parameters needed to evaluate the European Scleroderma Study Group (EScSG) activity index. A few studies have been so far devoted to investigate the clinical manifestations correlated with this finding. OBJECTIVE: To investigate SSc patients for hypocomplementemia and point out clinical manifestations associated with it. METHODS: 302 patients with SSc consecutively admitted to the Rheumatology Unit of the Second University of Naples were enrolled in the study. SSc patients were all investigated for sex, age, disease duration, clinical and serological subset, disease activity, organ/system severity and functional status. Patients were divided into 2 groups: normo-complementemic and hypocomplementemic (low C3 and/or C4) as measured by nephelometry. RESULTS: 252 of the 302 patients had normal complementemia; 50 (16,5%) had hypocomplementemia. Significant associations were found between hypocomplementemia and EScSG activity index (p<0.0003); functional disability (i.e. HAQ-DI >0.5)( p=0.04); and the severity of general manifestations (p<0.006); skin (p<0.0001); vascular (p<0.0001); heart (p<0.0001) and lung (p<0.0001) involvement. CONCLUSIONS: Our study confirms that hypocomplementemia occurs in patients with SSc. It resulted to be associated with disease activity, functional status and the severity of distinct disease manifestations.


Assuntos
Complemento C3/análise , Complemento C4/análise , Escleroderma Sistêmico/sangue , Escleroderma Sistêmico/complicações , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escleroderma Sistêmico/imunologia , Adulto Jovem
10.
Clin Exp Rheumatol ; 25(4): 613-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17888219

RESUMO

OBJECTIVE: To investigate the role of azathioprine in maintaining improvement after 1-year low-dose IV pulse CYC therapy in patients with early diffuse Systemic Sclerosis (dcSSc). METHODS: Thirteen patients with early dcSSc who had completed a year of treatment with low-dose IV pulse CYC underwent AZA treatment (100 mg/day) in a prospective 1-year study. Modified Rodnan skin score (mRss), Health Assessment Questionnaire-Disability Index (HAQ-DI), forced vital capacity (FVC), and diffusing lung capacity for CO (DLCO) were assessed as outcome measures. In addition, the nine organ/system Medsger et al. severity scores and the European Scleroderma Study Group (ESSG) activity index were evaluated. RESULTS: The improvement from a year of CYC therapy was maintained by AZA treatment. No outcome measures deteriorated (mRss 8.23 +/- 2.9 vs. 6.38 +/- 3.4; HAQ-DI 0.38 +/- 0.4 vs. 0.32 +/- 0.3; FVC 89.5 +/- 13.2 vs. 89.4 +/- 15.9; DLCO 73.6 +/- 14.4 vs. 75.0 +/- 19.5), nor were there any increases in any organ/system severity scores or ESSG activity index detected. CONCLUSION: This study suggests a role of AZA in maintaining the improvement induced by low dose pulse CYC in early dcSSc, making it possible a short duration of treatment at a low cumulative dose of the drug. These results, however, await confirmation in controlled studies.


Assuntos
Azatioprina/administração & dosagem , Ciclofosfamida/administração & dosagem , Imunossupressores/administração & dosagem , Pulsoterapia , Esclerodermia Difusa/tratamento farmacológico , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento
11.
Ann Rheum Dis ; 66(9): 1210-5, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17392350

RESUMO

OBJECTIVE: To investigate the relationship of the polymorphic enhancer HS1,2 central to the 3' enhancer complex regulatory region (IgH3'EC) of the immunoglobulin heavy chain genes with systemic sclerosis (SSc) disease and compare it with HLA-DR and DQ associations. METHODS: A total of 116 patients with SSc were classified as diffuse (dSSc) or limited (lSSc), and as carriers of antitopoisomerase I (anti-Scl70) or anticentromere (ACA) antibodies. Allele and genotype frequencies were assessed in the population as a whole and in the two major subsets, dSSc and lSSc. The concentration of peripheral blood immunoglobulin levels was also determined and analysed according to the genotypes. RESULTS: The analysis of genotypes for the four alleles of the HS1,2A enhancer showed an increased frequency of allele *2 in the SSc cohort highly significant versus controls (57% vs. 40%, p<0.0001). Considering the autoantibody pattern, we found that the frequency of the 2/2 genotype was increased in ACA+ patients (42%) and anti-Scl70+ patients (31%) compared with the control group (15%). The differences of allelic frequencies among dSSc versus lSSc or ACA+ versus anti-Scl70+ patients were not significant, although highly significant when comparing each subgroup with the control group. HLA-DRB1*11 and DQB1*03 associated with SSc. No association was seen between HS1,2A enhancer polymorphism and HLA alleles. CONCLUSIONS: These data confirm there was an increased risk of having SSc in carriers of allele *2, suggesting an intriguing function of this polymorphism for B-cell regulation.


Assuntos
Elementos Facilitadores Genéticos , Cadeias Pesadas de Imunoglobulinas/genética , Polimorfismo Genético , Escleroderma Sistêmico/imunologia , Adulto , Idoso , Autoanticorpos/sangue , Esôfago/patologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Antígenos HLA-DQ , Antígenos HLA-DR , Humanos , Masculino , Pessoa de Meia-Idade , Fenótipo , Escleroderma Sistêmico/genética , Escleroderma Sistêmico/patologia , Estatísticas não Paramétricas , Estômago/patologia
12.
Chemosphere ; 68(4): 724-30, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17292447

RESUMO

The evaluation of acute toxicity by Vibrio fischeri test for different organic chemicals (antibiotics, pesticides, therapeutants, herbicides) commonly applied in aquaculture and a degradation product of surfactants, 4-nonylphenol, is presented in this work. Simazine, atrazine, emamectin benzoate and leucomalachite green have no toxic effects on V. fischeri at the concentration tested (up to 6mgl(-1)) which correspond to the maximum water solubility. Ciprofloxacin, terbutryn and deltamethrin, caused inhibition effects of 28%, 22% and 30% at concentrations up to 5mgl(-1). Toxic effects were not observed in the case of flumequine and oxolinic acid at the maximum concentration tested (0.189mgl(-1)). According to the toxicity categories established in the EU legislation, ciprofloxacin, terbutryn and deltamethrin could be considered non-harmful for V. fischeri. Malachite green and 4-nonylphenol are "very toxic to aquatic organisms" (EC(50,30min)=0.031mgl(-1) and 0.48mgl(-1), respectively). Carbaryl is "toxic to aquatic organisms" (2.4mgl(-1)). and glyphosate is harmful to V. fischeri (EC(50,30min)=44.2mgl(-1)). The matrix effect was evaluated comparing the toxicity measurements of the target compounds solubilized in seawater and distilled water. Malachite green, 4-nonylphenol and glyphosate, showed higher toxicity in distilled water than in seawater. Carbaryl was more toxic in seawater. All the compounds tested in seawater were not harmful at concentrations of ngl(-1) (10 and 50). However, 4-nonlylphenol and malachite green may act as toxic compounds in the environment at a low ppb level, since both may be detected in water at this concentration level.


Assuntos
Aliivibrio fischeri/efeitos dos fármacos , Antibacterianos/toxicidade , Praguicidas/toxicidade , Aliivibrio fischeri/metabolismo , Aquicultura , Água Doce , Luminescência , Fenóis/toxicidade , Água do Mar , Tensoativos/toxicidade , Testes de Toxicidade Aguda
13.
Toxicol In Vitro ; 19(8): 1035-43, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16023322

RESUMO

A simple and rapid in vitro toxicological assay, utilizing submitochondrial particles (SMP), has been used to evaluate the toxic effects of fifteen herbicides belonging to the phenol and phenoxyalkanoic acid chemical classes. The SMP assay allows the quantitative evaluation of the toxicity of compounds with different mechanisms of action: uncouplers, inhibitors of the enzyme complexes involved in reverse electron transfer and in oxidative phosphorylation and chemicals that alter the membrane structure. The two groups of herbicides showed different levels of toxicity. For phenol derivatives, EC50 values ranged from 0.16 microM (ioxynil) to 6.7 microM (2,4-dinitrophenol), whereas for phenoxy herbicides EC50 values ranged from 21 microM (2,4,5-trichlorophenoxyacetic acid, 2,4,5-T) to 110 microM (4-chloro-2-methylphenoxyacetic acid, MCPA). On the average, the toxicity of phenolic compounds is greater than that of phenoxyalkanoic acids by two orders of magnitude. Quantitative structure-activity relationships (QSAR) were developed between EC50 values and various molecular descriptors. The results suggest the existence of different mechanisms of action for the two classes of compounds. The findings obtained for phenolic herbicides are consistent with a protonophoric uncoupling mechanism, whereas for phenoxy herbicides a non-specific mode of action at membrane level can be hypothesized.


Assuntos
Herbicidas/toxicidade , Fenóis/toxicidade , Partículas Submitocôndricas/efeitos dos fármacos , Animais , Bioensaio , Butiratos/toxicidade , Bovinos , Glicolatos/toxicidade , Técnicas In Vitro , NAD/biossíntese , Propionatos/toxicidade , Relação Quantitativa Estrutura-Atividade , Reprodutibilidade dos Testes , Partículas Submitocôndricas/metabolismo
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