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1.
Environ Toxicol ; 31(8): 970-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25899034

RESUMEN

Bacillus thuringiensis (Bt) has been widely used in foliar sprays as part of integrated pest management strategies against insect pests of agricultural crops. Since the advent of genetically modified plants expressing Bt δ-endotoxins, the bioavailability of Cry proteins has increased, and therefore for biosafety reasons their adverse effects should be studied, mainly for nontarget organisms. We evaluated, in Swiss mice, the hematotoxicity and genotoxicity of the genetically modified strains of Bt spore crystals Cry1Aa, 1Ab, 1Ac, or 2Aa at 27 mg/kg, and Cry1Aa, 1Ab and 2Aa also at 136 and 270 mg/kg, administered with a single intraperitoneal injection 24 h before euthanasia. Controls received filtered water or cyclophosphamide. Blood samples collected by cardiac puncture were used to perform hemogram, and bone marrow was extracted for the micronucleus test. Bt spore crystals presented toxicity for lymphocytes when in higher doses, which varied according to the type of spore crystal studied, besides promoting cytotoxic and genotoxic effects for the erythroid lineage of bone marrow, mainly at highest doses. Although the profile of such adverse side effects can be related to their high level of exposure, which is not commonly found in the environment, results indicated that these Bt spore crystals were not harmless to mice. This suggests that a more specific approach should be taken to increase knowledge about their toxicological properties and to establish the toxicological risks to nontarget organisms. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 970-978, 2016.


Asunto(s)
Proteínas Bacterianas/toxicidad , Endotoxinas/toxicidad , Proteínas Hemolisinas/toxicidad , Insecticidas/toxicidad , Animales , Bacillus thuringiensis/química , Toxinas de Bacillus thuringiensis , Daño del ADN , Femenino , Recuento de Linfocitos , Masculino , Ratones , Pruebas de Micronúcleos , Recuento de Plaquetas , Esporas/química
2.
Blood Cells Mol Dis ; 52(2-3): 95-107, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24567965

RESUMEN

We aimed to investigate the influence of haptoglobin (Hp) and myeloperoxidase (MPO - G463A; dbSNP rs2333227) gene polymorphisms on 78 sickle cell patients of a public hospital in the Federal District/Brazil with and without iron overload, to evaluate a possible association between these polymorphisms and clinical variability, response to treatment and prognosis. Data were obtained through laboratory tests, questionnaires, research in medical records and analyses of polymorphisms using PCR-based methods. Positive correlations were found between Hp and ferritin levels, hydroxyurea treatment, hospitalisation for and sequelae from stroke; and between MPO and number of hospitalizations in the past 12 months and splenectomy. Significant associations of specific Hp genotypes with comorbidities were also found, while results suggested that MPO AA homozygosis could increase effects of asplenia. Deviation from Hardy-Weinberg equilibrium, compatible with heterozygous deficit, was observed for Hp polymorphism. Odds ratio suggested the possibility that increased chance of hospitalisation for stroke (OR = 6.346; IC 95% = 1.56-25.79; p = 0.005) and sequelae of stroke (OR = 6.556; IC 95% = 1.578-27.237; p = 0.005) could be associated with lower frequency of 1S-2 than expected. In the interaction analyses, significant effects between subjects were shown only in the group without overload for Hp polymorphism in hs-CRP levels (p = 0.000) and number of transfusions (p = 0.018), and for MPO polymorphism (p = 0.000) and the interaction Hp/MPO (p = 0.000) in hs-CRP values. Results corroborate others indicating biological differences between Hp*1 alleles and highlight the importance of this study in understanding the biological significance of Hp and MPO polymorphisms in clinical variability and response to treatment of sickle cell patients.


Asunto(s)
Anemia de Células Falciformes/complicaciones , Anemia de Células Falciformes/genética , Haptoglobinas/genética , Sobrecarga de Hierro/etiología , Peroxidasa/genética , Polimorfismo Genético , Adulto , Anciano , Alelos , Anemia de Células Falciformes/terapia , Brasil , Estudios Transversales , Índices de Eritrocitos , Femenino , Frecuencia de los Genes , Genotipo , Humanos , Sobrecarga de Hierro/sangre , Sobrecarga de Hierro/diagnóstico , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Adulto Joven
3.
Toxins (Basel) ; 6(10): 2872-85, 2014 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-25268978

RESUMEN

The insecticidal properties of Cry-endotoxins from Bacillus thuringiensis (Bt) have long been used as spore-crystals in commercial spray formulations for insect control. Recently, some Bt-endotoxin genes have been cloned in many different plants. Toxicological evaluations of three spore-crystal endotoxins, BtCry1Ia, BtCry10Aa and BtCry1Ba6 from B. thuringiensis, were carried out on mice to understand their adverse effects on hematological systems and on genetic material. These three spore-crystals have shown toxic activity to the boll weevil, which is one of the most aggressive pests of the cotton crop. Cry1Ia, Cry10Aa and Cry1Ba6 did not increase the micronucleus frequency in the peripheral erythrocytes of mice and did not cause changes in the frequency of polychromatic erythrocytes. However, some hematologic disburbances were observed, specifically related to Cry1Ia and Cry1Ba6, respectively, for the erythroid and lymphoid lineage. Thus, although the profile of such adverse side effects can be related to their high level of exposure, which is not commonly found in the environment, results showed that these Bt spore-crystals were not harmless to mice, indicating that each spore-crystal endotoxin presents a characteristic profile of toxicity and might be investigated individually.


Asunto(s)
Bacillus thuringiensis/metabolismo , Proteínas Bacterianas/toxicidad , Daño del ADN/efectos de los fármacos , Endotoxinas/toxicidad , Proteínas Hemolisinas/toxicidad , Animales , Toxinas de Bacillus thuringiensis , Proteínas Bacterianas/genética , Proliferación Celular/efectos de los fármacos , Endotoxinas/genética , Proteínas Hemolisinas/genética , Ratones , Pruebas de Micronúcleos , Control Biológico de Vectores , Pruebas de Toxicidad
4.
J Nutr Biochem ; 25(11): 1161-1176, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25127291

RESUMEN

The development of therapeutic strategies to attenuate chemotherapy toxicity represents an area of great interest in cancer research, and among them is nutritional therapy based on antioxidants. As research on this topic is still controversial and scarce, we aim to investigate the effects of antioxidant supplementation with vitamin C, vitamin E or pequi oil, a carotenoid-rich oil extracted from pequi (Caryocar brasiliense), on doxorubicin (DX)-induced oxidative damage to normal cells in Ehrlich solid tumor-bearing mice. Tumor weight and volume, histopathology, morphometry and immunohistochemistry were used to assess the treatments' efficacy in containing tumor aggressiveness and regression, while possible toxicity of treatments was assessed by animals' weight, morphological analysis of the heart, liver and kidneys, hemogram, and serum levels of total bilirubin, direct bilirubin, indirect bilirubin, aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma glutamyl transferase (GGT), alkaline phosphatase, creatinine and urea. Although all the chemotherapeutic treatments increased internal necrosis area and reduced the positive Ki-67 cells compared to non-treated tumors, the treatments with pequi oil provided before tumor inoculation (PTDX) or in continuous and concurrent administration with doxorubicin (PTPDX) were more effective in containing tumor growth, besides increasing lymphocyte-dependent immunity and reducing the adverse side effects associated with DX-induced oxidative damage to normal cells, mainly the PTDX treatment. Vitamins C and E given before tumor inoculation and chemotherapy were not successful against doxorubicin-induced cardiotoxicity, besides increasing doxorubicin-induced nephrotoxicity, indicating that, at least for doxorubicin, pequi oil instead of vitamins C and E would be the best option to reduce its adverse effects.


Asunto(s)
Antibióticos Antineoplásicos/toxicidad , Carcinoma de Ehrlich/tratamiento farmacológico , Carotenoides/análisis , Doxorrubicina/toxicidad , Aceites de Plantas/química , Animales , Antibióticos Antineoplásicos/uso terapéutico , Ácido Ascórbico/análisis , Carcinoma de Ehrlich/metabolismo , Carcinoma de Ehrlich/patología , Doxorrubicina/uso terapéutico , Femenino , Ratones , Estrés Oxidativo/efectos de los fármacos , Aceites de Plantas/farmacología , Vitamina E/análisis
5.
Food Chem Toxicol ; 2012 Nov 09.
Artículo en Inglés | MEDLINE | ID: mdl-23146696

RESUMEN

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

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