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1.
Ecotoxicol Environ Saf ; 99: 21-7, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24183287

RESUMO

Pendimethalin, an herbicide active substance frequently used in terrestrial systems, has detected in European aquatic ecosystems. Reliable indicators still need to be found in order to properly assess the impact of pesticides in fish. After an in vivo chronic exposure to pendimethalin, the detoxification process and the antioxidant defense system were assessed in 120 adult rainbow trout, Oncorhynchus mykiss. Four nominal exposure conditions were tested: control (C), 500 ng L(-1) (P500), 800 ng L(-1) (P800) and the commercial formulation Prowl(®) at 500 ng L(-1) (Pw500). Fish samples were made after a 28 day exposure period (D28) and after a fifteen day recovery period in clean fresh water (D43). At D28, ethoxyresorufin-O-deethylase (EROD) activity was not activated in liver in spite of the pendimethalin uptake in fish. At D43, EROD activity in fish exposed to the commercial product was lower than in control fish, which may be explained by the high presence of herbicide in fish (613±163 ng g bile(-1)). Furthermore, antioxidant defense responses were set up by trout in gills and liver following chronic exposure to 800 ng L(-1) of pendimethalin concentration. While the glutathione content (GSH) decreased in gills, it increased in liver associated with higher activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD). These disturbances could lead to reactive oxygen species production and oxidative stress in the vital organs in fish. After fifteen days in clean water, while the SOD activity was restored, the GSH content and GPx activity were still significantly disturbed in fish exposed to pendimethalin in comparison with control. These significant differences between treatments in antioxidant defenses parameters measured, attesting to the irreversibility of the effects.


Assuntos
Compostos de Anilina/toxicidade , Exposição Ambiental , Brânquias/efeitos dos fármacos , Fígado/efeitos dos fármacos , Oncorhynchus mykiss/fisiologia , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Ativação Enzimática/efeitos dos fármacos , Brânquias/enzimologia , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Herbicidas/metabolismo , Herbicidas/farmacologia , Oncorhynchus mykiss/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
2.
Nat Commun ; 15(1): 2153, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38461323

RESUMO

The randomized, multicenter, double-blind, placebo-controlled, phase III PEONY trial (NCT02586025) demonstrated significantly improved total pathologic complete response (primary endpoint) with dual HER2 blockade in HER2-positive early/locally advanced breast cancer, as previously reported. Here, we present the final, long-term efficacy (secondary endpoints: event-free survival, disease-free survival, overall survival) and safety analysis (62.9 months' median follow-up). Patients (female; n = 329; randomized 2:1) received neoadjuvant pertuzumab/placebo with trastuzumab and docetaxel, followed by adjuvant 5-fluorouracil, epirubicin, and cyclophosphamide, then pertuzumab/placebo with trastuzumab until disease recurrence or unacceptable toxicity, for up to 1 year. Five-year event-free survival estimates are 84.8% with pertuzumab and 73.7% with placebo (hazard ratio 0.53; 95% confidence interval 0.32-0.89); 5-year disease-free survival rates are 86.0% and 75.0%, respectively (hazard ratio 0.52; 95% confidence interval 0.30-0.88). Safety data are consistent with the known pertuzumab safety profile and generally comparable between arms, except for diarrhea. Limitations include the lack of ado-trastuzumab emtansine as an option for patients with residual disease and the descriptive nature of the secondary, long-term efficacy endpoints. PEONY confirms the positive benefit:risk ratio of neoadjuvant/adjuvant pertuzumab, trastuzumab, and docetaxel treatment in this patient population.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias da Mama , Feminino , Humanos , Adjuvantes Imunológicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Docetaxel/uso terapêutico , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Receptor ErbB-2/uso terapêutico , Trastuzumab/uso terapêutico
3.
Artigo em Inglês | MEDLINE | ID: mdl-38751488

RESUMO

Background: The antibody-drug conjugate (ADCs) trastuzumab emtansine (T-DM1) is approved for human epidermal growth factor receptor 2 (HER2)-positive metastatic breast cancer (mBC) previously treated with trastuzumab and a taxane. The phase III ELAINA trial aimed to determine the clinical utility of T-DM1 in Chinese patients. Methods: ELAINA was a randomized, multicenter, open-label bridging study of Chinese patients with HER2-positive locally advanced breast cancer (LABC) or mBC previously treated with trastuzumab and a taxane. Using an interactive voice/internet response system, patients were randomized 3:1 to receive T-DM1 or lapatinib plus capecitabine. Patents were stratified by number of prior therapies in this disease setting and by presence of visceral disease using a permuted block randomization scheme. Patients received treatment until disease progression, unmanageable toxicity, or study termination. After that, data on survival and subsequent cancer therapies were collected at approximately 3-month intervals. The primary endpoint was investigator-assessed progression-free survival (PFS). Secondary endpoints were overall response rate, duration of response, overall survival (OS), safety, patient-reported quality of life, and pharmacokinetics (PKs). Results: ELAINA was fully enrolled with 200 patients randomized to T-DM1 (n=151) or lapatinib plus capecitabine (n=49). Median treatment duration was approximately 6 months in each study arm. Median follow-up time was approximately 9 months for all analyses except for OS. T-DM1 was associated with a 15% reduction in risk of disease progression or death compared with lapatinib plus capecitabine [stratified hazard ratio (HR) =0.85; 95% confidence interval (CI): 0.56-1.29] in the intent-to-treat (ITT) population. The objective response rate (ORR) was similar with T-DM1 (50.4%) and lapatinib plus capecitabine (55.8%); median duration of response was 8.4 months for both treatments. At a median follow-up time of approximately 30 months, OS was similar in each treatment arm. Incidence of grade ≥3 adverse events (AEs) was similar with T-DM1 (54.3%) and lapatinib plus capecitabine (57.1%). Grade ≥3 thrombocytopenia was greater with T-DM1 (40.4%) than with lapatinib plus capecitabine (4.1%); there was no grade ≥3 hemorrhage with either treatment. Conclusions: T-DM1 demonstrated an acceptable benefit-risk profile in Chinese patients with HER2-positive LABC/mBC previously treated with trastuzumab and a taxane. T-DM1 therefore provides a chemotherapy-free option in this setting. Trial Registration: ClinicalTrials.gov identifier: NCT03084939.

4.
Ecotoxicol Environ Saf ; 79: 28-34, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22361216

RESUMO

In this study, the in vivo effects of chronic pollution by the active substance (AS) pendimethalin, a dinitroaniline herbicide, on the susceptibility of rainbow trout, Oncorhynchus mykiss L., to an experimental challenge with viral hemorrhagic septicemia virus (VHSV) were assessed. After four weeks of exposure to fresh water (C group) or 500 ng L(-1) of AS (P500 group), the fish were challenged by immersion in water containing 10(4) TCID(50) mL(-1) of VHSV. While exposure to pendimethalin was maintained throughout the experiment, mortalities were recorded during the 40 days post-infection (dpi) and organs were collected from dead fish for virological examination. At the end of the experiment, anti-VHSV antibodies and the classical pathway of complement activity were assessed in trout plasma. Exposure to pendimethalin significantly affected the distribution of cumulative mortality accelerating death in fish infected by VHSV. Pendimethalin appeared to decrease the Mean Time to Death (MTD) after virus treatment from 14.9 days (C-VHSV) to 10.2 days (P500-VHSV). Nevertheless, by the end of the experiment, differences in cumulative mortality were no longer observed between the two groups, which had reached the same stage (50 percent). Furthermore, a higher concentration of the virus was recovered from the pools of organs from the P500-VHSV group than the C-VHSV group. Moreover, at 40 dpi, although no significant difference was observed in the immune response between the two groups, more fish in the P500-VHSV group had set up an immune response by secreting antibodies than in the control viral group (C-VSHV).


Assuntos
Compostos de Anilina/toxicidade , Septicemia Hemorrágica Viral , Herbicidas/toxicidade , Oncorhynchus mykiss/virologia , Animais , Formação de Anticorpos , Suscetibilidade a Doenças , Feminino , Masculino , Novirhabdovirus , Estresse Fisiológico , Poluentes Químicos da Água/toxicidade
5.
Membranes (Basel) ; 12(11)2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36422126

RESUMO

Cell membrane lipid composition, especially cholesterol, affects many functions of embedded enzymes, transporters and receptors in red blood cells (RBC). High membrane cholesterol content affects the RBCs' main vital function, O2 and CO2 transport and delivery, with consequences on peripheral tissue physiology and pathology. A high degree of deformability of RBCs is required to accommodate the size of micro-vessels with diameters significantly lower than RBCs. The potential therapeutic role of high-density lipoproteins (HDL) in the removal of cholesterol and its activity regarding maintenance of an optimal concentration of RBC membrane cholesterol have not been well investigated. On the contrary, the focus for HDL research has mainly been on the clearance of cholesterol accumulated in atherosclerotic macrophages and plaques. Since all interventions aiming at decreasing cardiovascular diseases by increasing the plasma level of HDL cholesterol have failed so far in large outcome studies, we reviewed the potential role of HDL to remove excess membrane cholesterol from RBC, especially in sickle cell disease (SCD). Indeed, abundant literature supports a consistent decrease in cholesterol transported by all plasma lipoproteins in SCD, in addition to HDL, low- (LDL) and very low-density lipoproteins (VLDL). Unexpectedly, these decreases in plasma were associated with an increase in RBC membrane cholesterol. The concentration and activity of the main enzyme involved in the removal of cholesterol and generation of large HDL particles-lecithin cholesterol ester transferase (LCAT)-are also significantly decreased in SCD. These observations might partially explain the decrease in RBC deformability, diminished gas exchange and tendency of RBCs to aggregate in SCD. We showed that incubation of RBC from SCD patients with human HDL or the HDL-mimetic peptide Fx5A improves the impaired RBC deformability and decreases intracellular reactive oxygen species levels. We propose that the main physiological role of HDL is to regulate the cholesterol/phospholipid ratio (C/PL), which is fundamental to the transport of oxygen and its delivery to peripheral tissues.

6.
Ecotoxicol Environ Saf ; 74(8): 2167-74, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21835465

RESUMO

The effects of Polycyclic Aromatic Hydrocarbons (PAHs) resulting from a water soluble fraction (WSF) of an Arabian crude oil were tested in vivo on the bioconcentration in muscles and on immune parameters in sea bass, Dicentrarchus labrax. After 15 days of acclimation, fish were acutely exposed (48 h) to the WSF of 25 g of oil, and then returned to clean sea water for a 15 day recovery period. PAH concentration in the WSF at the beginning of the exposure was estimated to 773±187 ng L⁻¹ similar to that observed in the marine environment after an oil spill. The WSF in the experimental system was composed by lightest PAH compounds and did not remain constant during the two days of exposure. Just after exposure to the WSF, a total mean concentration of 148±46 µg kg⁻¹ of PAHs was found in contaminated fish muscle, composed of parent and alkylated naphthalene compounds (86.5%), benzo[a]pyrene (10.1%) and benzo[b+k]fluoranthene (3.4%). In addition, a decrease of leucocytes counts due to a lymphopenia and granulopenia and an increase of the haemolytic activity of the alternative pathway (ACH50) were noted. After a 15 day recovery period, haematocrit was decreased whereas effects on the blood granulocytes of fish seemed to be reversible, contrary to the specific immune system and quality of flesh. In fact, contaminated fish had still less lymphocyte cells compared to controls fish and their flesh were still contaminated by naphthalene and benzo[a]pyrene creating a risk for human consumers.


Assuntos
Poluição por Petróleo/efeitos adversos , Petróleo/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bass/imunologia , Bass/metabolismo , Benzo(a)pireno/metabolismo , Benzo(a)pireno/toxicidade , Humanos , Músculos/metabolismo , Naftalenos/metabolismo , Naftalenos/toxicidade , Petróleo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Água do Mar/química , Poluentes Químicos da Água/metabolismo
7.
Environ Sci Pollut Res Int ; 21(24): 13769-78, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24659404

RESUMO

Chronic concentrations of polycyclic aromatic hydrocarbons (PAHs) have been commonly detected in international estuaries ecosystems. Reliable indicators still need to be found in order to properly assess the impact of PAHs in fish. After an in vivo chronic exposure to hydrocarbons, the enzymatic activity of 7-ethoxyresorufin O-deethylase (EROD) and the antioxidant defense system were assessed in sea bass, Dicentrarchus labrax. A total of 45 fish were exposed to the water-soluble fraction of Arabian crude oil, similar to a complex pollution by hydrocarbons chronically observed in situ, while 45 other control fish sustained the same experimental conditions in clean seawater. Fish samples were made after a 21-day exposure period and after a 15-day recovery period in clean fresh water. Throughout the experiment, liver EROD activity was significantly higher in contaminated fish than in control fish. In addition, nonenzymatic (total glutathione) and enzymatic (GPx, SOD, and CAT) antioxidant defense parameters measured in liver were not significantly different in fish. Furthermore, in gills, glutathione content had significantly increased while SOD activity had significantly decreased in contaminated fish compared to controls. On the other hand, CAT and GPx activities were not affected. Chronic exposure to PAHs disturbing the first step (SOD) and inhibiting the second step (GPx and CAT) could induce oxidative stress in tissues by the formation of oxygen radicals. After the postexposure period, there was no significant difference between control and contaminated fish in any of the antioxidant defense parameters measured in gills, attesting to the reversibility of the effects.


Assuntos
Antioxidantes/metabolismo , Bass/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Proteínas de Peixes/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Brânquias/metabolismo , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Estresse Oxidativo , Petróleo/efeitos adversos , Poluição por Petróleo/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise
8.
Sci Total Environ ; 424: 143-52, 2012 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-22444063

RESUMO

The in vivo effects of the herbicide active substance (AS) pendimethalin (alone and with Prowl 400® adjuvant) were evaluated on sanitary status i.e. the health status with regard to chemical pollution and on the physiological state via the immune system in rainbow trout, Oncorhynchus mykiss. Four nominal exposure conditions were tested: i) control (C), ii) AS at 500 ng L(-1) (P500), iii) AS at 800 ng L(-1) (P800) and iv) Prowl 400® at 500 ng L(-1) (Pw). After a 28 day exposure period (D28), 10 fish were sampled for each condition and 10 other after a 15 day recovery period in clean fresh water (D43). Pendimethalin concentrations in the exposure water and muscles were followed. White blood cell counts, differential leucocyte counts, cell mortality and phagocytosis activity were measured. Haemolytic alternative complement activity, lysozyme concentration and stress parameters were analyzed. The resulting concentration of pendimethalin in the exposure water was lower than the expected concentration. At D28, the concentration quantified in the contaminated fish was negligible in comparison with the Reference Dose for Oral Exposure estimated by US-EPA's Integrated Risk Information System. Leucopenia was noted in all contaminated fish. A decrease in phagocytosis activity and ACH(50) was also observed in contaminated fish by P800 and Pw. Disturbed lysozyme activity was noted only in fish exposed to Pw. Furthermore, during exposure to a similar concentration of pendimethalin, the commercial product seemed to be more immunotoxic than the AS alone. Finally, at D43, the effects proved reversible for sanitary status while immunity was still disturbed in contaminated fish by P800 and Pw.


Assuntos
Compostos de Anilina/toxicidade , Herbicidas/toxicidade , Oncorhynchus mykiss/imunologia , Oncorhynchus mykiss/metabolismo , Poluentes Químicos da Água/toxicidade , Animais , Análise Química do Sangue , Relação Dose-Resposta a Droga , Monitoramento Ambiental , Cromatografia Gasosa-Espectrometria de Massas , Músculo Esquelético/química , Músculo Esquelético/efeitos dos fármacos , Oncorhynchus mykiss/sangue , Distribuição Aleatória , Espectrometria de Massas em Tandem , Fatores de Tempo
9.
Aquat Toxicol ; 105(3-4): 300-11, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21781655

RESUMO

Following the development of an experimental system to expose adult fish to low and stable concentration of pollutant over a prolonged period, the in vivo effects of hydrocarbons on sanitary status, i.e. the health status of fish with regard to chemical pollution, and immune system in sea bass, Dicentrarchus labrax were assessed. A total of 90 fish were acclimated for 15 days, then 45 fish were exposed to the water soluble fraction (WSF) of Arabian crude oil, similar to a complex pollution by hydrocarbons chronically observed in situ in estuaries, while the 45 other control fish sustained the same experimental conditions in clean seawater. After 21 days of exposure, 30 contaminated and control fish were sampled, then 30 other fish were collected after a 15 day recovery period in clean sea water. PAH concentrations in crude oil, WSF, muscles and bile were measured by gas chromatography coupled with mass spectrometry analysis. White blood cell counts and differential leucocyte counts were determined by classical haematology methods. Cell mortality and phagocytosis activity of leucocytes were analyzed by flow cytometry. Haemolytic alternative complement activity and stress parameters were analyzed in blood plasma by spectrophotometry. After a 21 day exposure period to a mixture of 41 parent/alkylated-PAHs (835 ± 52/85 ± 1 5 ng L(-1)). Fish flesh was contaminated by a bioconcentration of naphthalene very closed to the Reference Dose for Oral Exposure estimated by US-EPA's Integrated Risk Information System, causing a potential risk for human consumers. A leucopenia due to a lymphopenia, a rise in leucocyte mortality and a decrease in phagocytosis activity were noted in contaminated fish compared to controls. All these results may be explained by the damage to membrane cells integrity by uptake of PAHs and suggested an impairment of specific and nonspecific immune systems. After a 15 day recovery period, effects were reversible for sanitary status and an offset in immunity was noted by a significant increase in leucocytes in contaminated fish compared to controls.


Assuntos
Bass/imunologia , Leucopenia/induzido quimicamente , Linfopenia/induzido quimicamente , Petróleo/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Bass/sangue , Carga Corporal (Radioterapia) , Cromatografia Gasosa-Espectrometria de Massas , Nível de Saúde , Contagem de Leucócitos , Leucócitos/fisiologia , Fagócitos/fisiologia , Hidrocarbonetos Policíclicos Aromáticos/análise , Distribuição Aleatória , Testes de Toxicidade Crônica
10.
Gastroenterology ; 127(6): 1724-32, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15578510

RESUMO

BACKGROUND & AIMS: Patients with chronic hepatitis C and persistently normal alanine aminotransferase (ALT) levels have been routinely excluded from large randomized treatment trials; consequently, the efficacy and safety of antiviral therapy in this population are unknown. METHODS: Patients with at least 3 normal ALT values over an 18-month period were randomized (3:3:1) to treatment with peginterferon alfa-2a 180 mug/wk plus ribavirin 800 mg/day for 24 weeks (212 patients), the same combination for 48 weeks (210 patients), or no treatment (69 patients) in a multinational study. All patients were monitored for 72 weeks. The primary measure of efficacy was sustained virologic response (SVR), defined as undetectable serum hepatitis C virus (HCV) RNA by qualitative polymerase chain reaction at the end of 24 weeks of untreated follow-up. RESULTS: No patient cleared HCV RNA in the untreated control group. SVR rates of 30% and 52% were obtained in the 24- and 48-week treatment groups, respectively. In patients infected with HCV genotype 1, SVR rates of 13% and 40% were obtained with 24 and 48 weeks of treatment, respectively (P < .0001). In patients infected with genotypes 2 or 3, SVR rates were 72% and 78% with 24 and 48 weeks of treatment, respectively (P = .452). Treatment-related flares in ALT activity were not observed. CONCLUSIONS: The efficacy and safety of peginterferon alfa-2a and ribavirin combination therapy in patients with chronic hepatitis C and persistently normal ALT levels are similar to that in patients with elevated ALT levels. The indication for treatment of hepatitis C can be evaluated independently from baseline ALT activity.


Assuntos
Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Polietilenoglicóis/administração & dosagem , Ribavirina/administração & dosagem , Adulto , Alanina Transaminase/sangue , Antivirais/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Injeções Subcutâneas , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/efeitos adversos , RNA Viral/análise , Proteínas Recombinantes , Resultado do Tratamento
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