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1.
Toxics ; 11(5)2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37235221

RESUMO

Estuaries are heavily impacted by pollutants from different sources such as urban sewage, industrial waste and agricultural runoff. Endocrine-disrupting chemicals (EDCs) are very concerning pollutants to estuarine wildlife, but little is known about their impact on microscopic biota such as zooplankton. The aim of this work was to investigate the effects of a model EDC, the 17α-ethinylestradiol (EE2), on two copepod species inhabiting the Basque coast (Southeastern Bay of Biscay) estuaries: Acartia clausi (autochthonous neritic species) and Acartia tonsa (non-indigenous brackish species). Female copepods were collected at population maximum time (spring for A. clausi and summer for A. tonsa) and exposed individually to 5 ng/L (low), 5 µg/L (medium) and 500 µg/L EE2 (high) doses, from environmental concentrations found in sewage effluents to toxicological concentrations. After 24 h exposure, the survival rate of experimental individuals was checked and the lethal concentration LC50 was calculated. The number of egg-producing females and the amount of egg laying and egg hatching were recorded. The integrated biomarker index (IBR) was calculated to integrate the overall effects of EE2 exposure. Both species had reduced survival rates at 500 µg/L, and the LC50 was lower in A. tonsa (158 µg/L) compared to A. clausi (398 µg/L). The number of eggs laid was significantly reduced in A. clausi at EE2 medium and high doses, while a reduction in the number of eggs in A. tonsa was observed only at the high dose. However, no significant differences were detected in the egg hatching success of exposed A. clausi and A. tonsa. IBR index showed that EE2 had the most detrimental effects on A. tonsa and A. clausi females at the 500 µg/L dose. In conclusion, after 24 h of exposure, EE2 reduced female copepod survival and disrupted reproductive output, but only at high non-environmentally relevant concentrations.

2.
Environ Sci Pollut Res Int ; 30(15): 44640-44656, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36694068

RESUMO

In cold environments, the low temperature slows down microbial metabolisms, such as the biodegradation processes of hydrocarbons, which are often stimulated by the addition of dispersants in oil spill disasters. In this study, we investigated the effects of hydrocarbon water-accommodated fraction (WAF) prepared with and without dispersant on benthic microbial communities in a microcosm experiment in which hydrocarbon removal was observed. Both WAFs contained similar polycyclic aromatic hydrocarbon (PAH) content. The microcosm experiment, set up with either pristine or contaminated sediments, was conducted for 21 days at 4 °C under WAF and WAF + dispersant conditions. The behavior of bacterial communities in response to WAF and WAF + dispersant was examined at both DNA and RNA levels, revealing the effect of WAF and WAF + dispersant on the resident and active communities respectively. The contaminated sediment showed less taxa responsive to the addition of both WAF and WAF + dispersant than the pristine sediment, indicating the legacy effect by the presence hydrocarbon-degrading and dispersant-resistant taxa inhabiting the contaminated sediment.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Água , Petróleo/análise , Poluentes Químicos da Água/análise , Hidrocarbonetos , Poluição por Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise
3.
Environ Res ; 212(Pt D): 113467, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35588780

RESUMO

Dispersants, used for combating oil spills, increase hydrocarbon bioavailability promoting their biodegradation. Oil weathering process introduces harmful soluble hydrocarbons, such as polycyclic aromatic hydrocarbons (PAHs), into the water column, resulting in water-accommodated fraction (WAF). The presence of dispersants can influence the weathering process by increasing PAHs solubility, toxicity and biodegradability. However, little is known on how dispersants affect microbial communities and their degradation capacities, especially in cold environment where low temperature decreases microbial activity and thus hydrocarbon degradation. Here, we investigated the microbial community dynamics in cold water contaminated by WAF prepared from crude oil with or without a commercial dispersant (Finasol OSR52). The WAFs, prepared with Naphthenic North Atlantic crude oil, were used to contaminate seawater from Norwegian cold sites, one oil-contaminated and the other pristine. The WAF-contaminated seawaters were maintained in microcosms at 4 °C for 21 days. The content of PAHs and microbial compositions (16S rRNA gene sequencing) were determined at days 0, 7, 14 and 21. In addition, the 96 h toxicity assay with adult Acartia tonsa revealed WAFs toxicity at days 0 and 21. The toxicity of WAF mixtures, with and without dispersant, against Acartia tonsa was reduced during the experiment, but PAHs removal was not increased. The water from the oil-contaminated site showed the highest PAHs removal revealing legacy effect (presence of microorganisms adapted to PAHs). Additionally, our results reveal: i) microbial community plasticity allowing the adaptation to the presence of PAHs and dispersant, ii) specific bacteria taxa probably involved in PAHs degradation, and iii) dispersants shape the microbial communities dynamics by stimulating potential dispersant-degrading taxa, such as Fusibacter. Thus, our results provide valuable insights on the role of microbial community in determining the fate of water-solubilized hydrocarbon in cold environment while questioning the role of dispersant used for fighting oil spill.


Assuntos
Microbiota , Poluição por Petróleo , Petróleo , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Hidrocarbonetos , Petróleo/análise , Petróleo/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , RNA Ribossômico 16S/genética , Água do Mar , Água , Poluentes Químicos da Água/análise
4.
Mar Environ Res ; 169: 105378, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34102532

RESUMO

Copepods play a critical role in the marine food webs, being a food source for marine organisms. In this study, we investigated the toxic effects of Water Accommodated Fractions (WAFs) from three types of oil: Naphthenic North Sea crude oil (NNS), Intermediate Fuel Oil (IFO 180) and a commercial Marine Gas Oil (MGO). The WAFs were prepared at 10 °C and 30 PSU (practical salinity unit), and tested on the marine copepod Acartia tonsa at different endpoints and at different levels of biological organization. We determined the median lethal concentrations after 96 h (LC50) and reproduction capabilities were calculated in adult females following seven days of exposure to sublethal WAF doses. The total lipid content was measured in reproductive females using Nile red lipophilic dye after 96 h of WAF exposure. We also measured the transcription levels of genes involved in antioxidant response and xenobiotic biotransformation after short exposure for 48 h. High doses (7% WAF) of MGO affected survival, percentage of fecund females, egg hatching success, and total lipid content. The IFO 180 WAF affected, at medium (20%) and high (40%) doses, the number of fecund females, mortality and produced significant effects on gene expression levels. In conclusion, toxicity assays showed that the WAFs prepared from refined oils were more toxic than crude oil WAF to Acartia tonsa.


Assuntos
Copépodes , Petróleo , Poluentes Químicos da Água , Animais , Feminino , Mar do Norte , Petróleo/toxicidade , Água , Poluentes Químicos da Água/toxicidade
5.
BMC Gastroenterol ; 19(1): 22, 2019 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-30717703

RESUMO

BACKGROUND: Gilbert syndrome (GS) is an autosomal recessive inherited disorder of bilirubin glucuronidation which has not been investigated in Egypt. This longitudinal study investigated the frequency, clinical course, genetic profile and health related quality of life in Egyptian adults. METHODS: An initial cross-sectional study was conducted to assess the frequency of Gilbert syndrome among Egyptian adults. Subjects fulfilling the criteria of GS were enrolled into the study and prospectively followed for the clinical features, risk factors for hyperbilirubinemia, health related quality of life [Short form-36 Health Survey version 2 (SF-36v2) and Chronic Liver Disease Questionnaire (CLDQ)], vitamins assessment and UGT1A1 polymorphisms. RESULTS: One hundred and one subjects fulfilled the criteria of GS with a prevalence of 8.016%. Recurrent jaundice was the only presentation in 47 (56.627%) GS subjects and jaundice was associated with abdominal pain, dyspepsia or loss of appetite in 54 (53.465%) subjects. A significant difference in 25-Hydroxyvitamin D3 levels was detected between GS patients and control subjects (P <  00001). Twelve subjects with GS developed significant unconjugated bilirubinemia during direct antiviral therapy (DAAs) therapy for HCV despite achieving sustained virologic response. Pregnancy was associated with significant exacerbation of unconjugated bilirubin which persisted through pregnancy. Risk factors for clinical jaundice included general anesthesia, pregnancy, fasting > 12 h, pregnancy, and low calorie weight losing plans, systemic infections, and intensive physical effort. During jaundice attacks, subjects with GS had significant differences in vitality, role emotional, social functioning, worry and general health domains of the SF-36v2 and CLDQ compared to controls. The homozygous polymorphism A(TA)7TAA was the most frequent polymorphism in Egyptians with GS. CONCLUSION: Gilbert syndrome is a frequent inherited disorder in Egypt. In a substantial percentage of subjects with GS, episodes of jaundice are associated with other symptoms and nutritional deficiencies which result in impairment of HRQOL. Screening, counseling, monitoring and individualized health care are recommended for subjects with GS in the setting of anesthesia, pregnancy, treatment with DAAs, deliveries, surgery and weight loss plans.


Assuntos
Doença de Gilbert/complicações , Doença de Gilbert/epidemiologia , Qualidade de Vida , Dor Abdominal/etiologia , Adolescente , Adulto , Estudos Transversais , Dispepsia/etiologia , Egito/epidemiologia , Transtornos da Alimentação e da Ingestão de Alimentos/etiologia , Feminino , Genótipo , Doença de Gilbert/genética , Doença de Gilbert/psicologia , Glucuronosiltransferase/genética , Humanos , Icterícia/etiologia , Estudos Longitudinais , Masculino , Polimorfismo Genético , Prevalência , Recidiva , Fatores de Risco , Adulto Jovem
6.
BMJ Open Gastroenterol ; 5(1): e000150, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29503733

RESUMO

OBJECTIVE: Concomitant non-alcoholic fatty liver disease (NAFLD) and coeliac disease (CD) have not been adequately studied. This study investigated the frequency of CD among NAFLD patients and the clinicopathological and immunological patterns and outcome of concomitant NAFLD and CD. DESIGN: This prospective longitudinal study screened patients with NAFLD for CD (tissue transglutaminase antibodies (TTGA); anti-TTGA and antiendomysial antibodies (EMA)). Patients with concomitant NAFLD and CD and patients with either NAFLD or CD were enrolled and followed. Duodenal biopsy, transient elastography, tumour necrosis factor (TNF)-alpha, transforming growth factor-beta, interleukins (ILs) 1, 6, 10, 15 and 17, folic acid and vitamins B12 and D were performed at baseline and 1 year after gluten-free diet (GFD). RESULTS: CD was confirmed in 7.2% of patients with NAFLD. Refractory anaemia and nutritional deficiencies were frequent in patients with concomitant NAFLD and CD who had advanced intestinal and hepatic lesions, higher levels of TNF-α, IL-15 and IL-17 compared with patients with CD and NAFLD. Patients concomittant CD and NAFLD showed clinical response to GFD, but intestinal histological improvement was suboptimal. Combining EMA-IgA or anti-TTGA with either IL-15 or IL-17 enhances the prognostic performance of both tests in predicting histological response to GFD. CONCLUSION: Concomitant NAFLD and CD is not uncommon. Recurrent abdominal symptoms, refractory anaemia, nutritional deficiencies in patients with NAFLD warrant screening for CD. The study has important clinical implications since failure in diagnosing CD in patients with NAFLD patients results in marked intestinal and hepatic damage and suboptimal response to GFD that can be alleviated by early diagnosis and initiation of GFD.

7.
Am J Gastroenterol ; 109(2): 199-211, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24445571

RESUMO

OBJECTIVES: The objective of this study was to characterize the factors that influence the outcome of exposure to hepatitis C virus (HCV) genotype 4 (HCV-G4) and the course of recent infection. METHODS: In this longitudinal study, we prospectively assessed the clinical, genetic, virological, and immunological parameters and retrospectively determined single-nucleotide polymorphisms at interleukin-28B (IL-28B) rs12979860 in a well-characterized large cohort recently exposed to HCV-G4. RESULTS: A total of 136 subjects with acute HCV (new viremia, seroconversion, and HCV-specific T-cell responses) were identified. Forty-eight subjects (35%) had spontaneous viral clearance and 88 subjects developed chronic HCV of which 42 subjects were treated with pegylated interferon monotherapy, with a sustained virologic response (SVR) rate of 88%. Twenty-six subjects developed HCV-specific T-cell immune responses without detectable viremia or seroconversion. IL-28B-CC (odds ratio (OR) 14.22; P<0.0001), multispecific T-cell responses (OR=11.66; P<0.0001), >300 IU/l alanine aminotransferase (ALT) decline within 4 weeks (OR=6.83; P<0.0001), jaundice (OR=3.54; P=0.001), female gender (OR=2.39; P=0.007), and >2.5 log10 HCV-RNA drop within 8 weeks (OR=2.48; P=0.016) were independently associated with spontaneous clearance. ALT normalization and undetectable HCV-RNA predicted SVR. Exposed apparently uninfected participants had a higher frequency of IL-28B-CC than patients with unresolved acute HCV (P<0.001). IL-28B-CC was associated with multispecific T-cell response (r(2)=0.0.835; P<0.001). CONCLUSIONS: IL-28B-CC genotype, multispecific HCV T-cell responses, rapid decline in ALT, and viral load predict spontaneous clearance and response to acute HCV-G 4 therapy. IL-28B-CC genotype correlates with developing early multispecific T-cell responses. These findings have important implications for predicting the outcome of HCV exposure and acute infection and identifying patients likely to benefit from therapy.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/genética , Hepatite C/epidemiologia , Hepatite C/genética , Interleucinas/genética , Viremia/epidemiologia , Doença Aguda , Adulto , Distribuição por Idade , Estudos de Casos e Controles , Intervalos de Confiança , Progressão da Doença , Egito/epidemiologia , Feminino , Vírus GB C/genética , Vírus GB C/isolamento & purificação , Genótipo , Hepacivirus/efeitos dos fármacos , Hepatite C/tratamento farmacológico , Humanos , Incidência , Interferons , Estimativa de Kaplan-Meier , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Prognóstico , Estudos Prospectivos , RNA Viral/análise , RNA Viral/genética , Ribavirina/uso terapêutico , Distribuição por Sexo , Estatísticas não Paramétricas , Resultado do Tratamento , Carga Viral/genética , Viremia/genética
8.
Liver Int ; 31(3): 401-11, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21281434

RESUMO

AIM: The therapy of chronic hepatitis C genotype 4 (HCV-4) has not been optimized yet. This randomized, prospective, parallel-group clinical trial compared the efficacy and safety of pegylated interferon α-2a (PEG-IFN α-2a) plus ribavirin and PEG-IFN α-2b plus ribavirin and assessed the health-related quality of life (HRQOL) in patients with chronic HCV-4. METHODS: Eligible patients with proven chronic HCV-4 were randomized to receive either a weekly dose of PEG-IFN α-2a (180 µg) or PEG-IFN α-2b (1.5 µg/kg) and a daily dose of ribavirin (1000-1200 mg) for 48 weeks with 24 weeks post-treatment follow-up. The primary end point was sustained virological response (SVR) defined by undetectable HCV RNA 24 weeks after treatment. The Short form-36 Health Survey version 2 (SF-36v2) and the Chronic Liver Disease questionnaires (CLDQ) were assessed before, during and after therapy. RESULTS: The overall SVR rate of the entire cohort was 59.9%. The SVR rates were significantly higher in patients treated with PEG-IFN α-2a and ribavirin (Group A; n=109) compared with those treated with PEG-IFN α-2b and ribavirin (Group B; n=108, 70.6 vs. 54.6%, respectively; P=0.017). The relapse rates were 5.1% for PEG-IFN α-2a and 15.7% for PEG-IFN α-2b (P=0.0019). The SF-36v2 and CLDQ were low during therapy and improved significantly after therapy successful therapy. CONCLUSION: Pegylated interferon α-2a plus ribavirin was significantly more effective than PEG-IFN α-2b and ribavirin therapy in the treatment of chronic HCV-4 patients. The tolerability and adverse events were comparable between the two regimens. The HRQOL improved significantly after successful PEG-IFN α-2a plus ribavirin therapy.


Assuntos
Antivirais/uso terapêutico , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Ribavirina/uso terapêutico , Atividades Cotidianas , Adulto , Quimioterapia Combinada , Feminino , Nível de Saúde , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/sangue , Hepatite C Crônica/virologia , Humanos , Interferon alfa-2 , Masculino , Qualidade de Vida , RNA Viral/sangue , Proteínas Recombinantes , Carga Viral/efeitos dos fármacos
9.
Mediterr J Hematol Infect Dis ; 2(1): e2010001, 2010 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-21415943

RESUMO

Viral hepatitis represents an important health problem in the South Mediterranean countries, Egypt, Libya, Tunisia, Algeria and Morocco. Emerging natural history and epidemiological information reveal differences in the overall epidemiology, risk factors and modes of transmission of viral hepatitis A, B, C, D, E infections in the South Mediterranean region. The differences in the in incidence and prevalence of viral hepatitis across North African countries is attributed to variations in health care and sanitation standards, risk factors and immunization strategies. The active continuous population movement through travel, tourism and migration from and to the South Mediterranean countries contribute to the spread of infections due to hepatitis viruses across borders leading to outbreaks and emergence of new patterns of infection or introduction of uncommon genotypes in other countries, particularly in Europe.

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