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1.
J Toxicol Environ Health A ; 81(14): 604-619, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29737961

RESUMO

Cobalt ferrite nanoparticles (NPs) have received increasing attention due to their widespread therapeutic and agricultural applicability. In the environmental field, dry powder- and ferrofluid-suspended cobalt ferrite NPs were found to be useful for removing heavy metals and metalloids from water, while diluted suspensions of cobalt ferrite NP have been promisingly applied in medicine. However, the potential toxicological implications of widespread exposure are still unknown. Since cobalt ferrite NPs are considered residual wastes of environmental or medical applications, plants may serve as a point-of-entry for engineered nanomaterials as a result of consumption of these plants. Thus, the aim of this study was to assess the effects of dry powder and fresh cobalt ferrite NP on wheat plants. Seven-day assays were conducted, using quartz sand as the plant growth substrate. The toxicity end points measured were seed germination, root and shoot lengths, total cobalt (Co) and iron (Fe) accumulation, photosynthetic pigment production, protein (PRT) production, and activities of catalase (CAT), ascorbate peroxidase (APX), and guaiacol peroxidase (GPX). Increasing total Co and Fe in plant tissues indicated that wheat plants were exposed to cobalt ferrite NP. Seed germination and shoot length were not sufficiently sensitive toxicity end points. The effective concentration (EC50) that diminished root length of plants by 50% was 1963 mg/kg for fresh ferrite NPs and 5023 mg/kg for powder ferrite NP. Hence, fresh ferrite NPs were more toxic than powder NP. Plant stress was indicated by a significant decrease in photosynthetic pigments. CAT, APX, and GPX antioxidant enzymatic activity suggested the generation of reactive oxygen species and oxidative damage induced by cobalt ferrite NP. More studies are thus necessary to determine whether the benefits of using these NPs outweigh the risks.


Assuntos
Cobalto/toxicidade , Compostos Férricos/toxicidade , Estresse Oxidativo , Fotossíntese/efeitos dos fármacos , Triticum/efeitos dos fármacos , Antioxidantes/metabolismo , Cobalto/química , Compostos Férricos/química , Germinação/efeitos dos fármacos , Nanopartículas Metálicas , Pigmentos Biológicos/metabolismo , Proteínas de Plantas/biossíntese , Pós/química , Pós/toxicidade , Plântula/crescimento & desenvolvimento , Sementes/efeitos dos fármacos , Sementes/enzimologia , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Testes de Toxicidade , Triticum/enzimologia , Triticum/crescimento & desenvolvimento , Triticum/fisiologia
2.
Sci Total Environ ; 565: 941-950, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26806072

RESUMO

The aim of this work was to assess the uptake of citrate-coated magnetite nanoparticles (NPs) by wheat plants and its effect on the bioaccumulation and toxicity of individual and joint Cd(2+) and Cr(6+) levels. Seven-day assays were conducted using quartz sand as the plant growth substrate. The endpoints measured were seed germination, root and shoot lengths, and heavy metal accumulation. Magnetite exhibited very low toxicity, regardless of the wheat seedling NP uptake and distribution into roots and shoots. The seed germination and shoot length were not sensitive enough, while the root length was a more sensitive toxicity endpoint. The root length of wheat seedlings exposed to individual metals decreased by 50% at 2.67mgCd(2)(+)kg(-1) and 5.53mgCr(6+)kg(-1). However, when magnetite NPs (1000mgkg(-1)) were added, the root length of the plants increased by 25 and 50%. Cd(2+) and Cr(6+) showed similar and noninteractive joint action, but strongly impaired the wheat seedlings. In contrast, an interactive infra-additive or antagonistic effect was observed upon adding magnetite NPs. Thus, cadmium and chromium accumulation in vegetable tissues was considerately diminished and the toxicity alleviated.


Assuntos
Cádmio/toxicidade , Cromo/toxicidade , Nanopartículas de Magnetita/toxicidade , Poluentes do Solo/toxicidade , Triticum/efeitos dos fármacos , Ácido Cítrico/química , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Brotos de Planta/efeitos dos fármacos , Brotos de Planta/crescimento & desenvolvimento , Brotos de Planta/metabolismo , Plântula/efeitos dos fármacos , Plântula/crescimento & desenvolvimento , Triticum/crescimento & desenvolvimento , Triticum/metabolismo
3.
Artigo em Inglês | MEDLINE | ID: mdl-22320693

RESUMO

This study was conducted to assess the effect of tannery sludge on the bush bean (Phaseolus vulgaris) cultivars fully-grown on a culture sandy soil, as tannery sludge is valuable to improve soil fertility but long term studies evaluating the effect on fully grown plants are scarce. Tannery sludge amendments (0, 0.77, 1.54, 3.08 and 6.16 g tannery sludge kg(-1) soil) were characterized and the main heavy metals identified (Cr, Mn, Fe, K, and Zn) later on sequentially and singly extracted, for soil fractionation and availability determination, respectively. Metals showed different fractionation and availability patterns, being the most toxic metal (Cr) found to primarily bind to the carbonate fraction in soil, while almost 10% of the total Cr was available for plant uptake. In the green house experiments, bush bean cultivars exposed to increasing tannery sludge amendments were evaluated at different plant stages. Metal accumulation and physiological parameters (chlorophyll, carotenoids, nitrate reductase activity and dry weight) were determined. Toxicity was primarily due to Cr, stimulating or affecting the response of physiological parameters and suppressing seed formation at the highest tannery sludge ratio. Metals were mainly accumulated in the roots of bush beans, diminishing in the upper part of the plants with minimal translocation to seeds, supposing little risk for human consumption. Additionally, important correlations, antagonistic and synergistic relationships were observed between the extracted metals and metal accumulation in plant tissues.


Assuntos
Metais Pesados/análise , Metais Pesados/toxicidade , Phaseolus/efeitos dos fármacos , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Carbonatos/análise , Carotenoides/metabolismo , Fracionamento Químico , Clorofila/metabolismo , Resíduos Industriais/análise , Metais Pesados/química , Nitrato Redutase/metabolismo , Óxidos/análise , Phaseolus/crescimento & desenvolvimento , Phaseolus/metabolismo , Componentes Aéreos da Planta/efeitos dos fármacos , Componentes Aéreos da Planta/crescimento & desenvolvimento , Componentes Aéreos da Planta/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Solo/química , Poluentes do Solo/química , Curtume
4.
J Hazard Mater ; 163(2-3): 829-34, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18814962

RESUMO

This work assessed the effect of soil amended with tannery sludge (0, 500, 1000, 2000, 4000 and 8000 mg Cr kg(-1)soil), Cr(3+) as CrCl(3).6H(2)O (0, 100, 250, 500, 1000 and 2000 mg Cr kg(-1)soil), and Cr(6+) as K(2)Cr(2)O(7) (0, 25, 50, 100, 200 and 500 mg Cr kg(-1)soil) on wheat, oat and sorghum plants. Seed germination, seedling growth (root and shoot) and Cr accumulation in dry tissue were measured. Toxicological parameters; medium effective concentration, no observed adverse effect concentration and low observed adverse effect concentration were determined. Root growth was the most sensitive assessment of Cr toxicity (P<0.05). There was a significant correlation (P<0.0001) between Cr accumulation in dry tissue and toxic effects on seedling growth. The three Cr sources had different accumulation and mobility patterns; tannery sludge was less toxic for all three plant species, followed by CrCl(3).6H(2)O and K(2)Cr(2)O(7).


Assuntos
Cromo/toxicidade , Monitoramento Ambiental/métodos , Plantas/efeitos dos fármacos , Esgotos/efeitos adversos , Solo , Avena , Germinação/efeitos dos fármacos , Desenvolvimento Vegetal , Sorghum , Triticum
5.
Lung Cancer ; 54(2): 163-8, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16959370

RESUMO

Experimental evidence suggests that in lung cancer, development, progression and an increased proliferation rate can be linked to apoptosis-related factors. The objective of this study is to evaluate the status of Neu, signal transducer and activator of transcription (STAT)-3, STAT5 and Bcl-xL expression in non-small-cell lung cancer. We investigated the immunohistochemical expression of these proteins in 92 non-small-cell lung cancer specimens to establish their role in lung cancer pathogenesis. Neu was overexpressed in 65% of cases, and although STAT3 was overexpressed in 52.1% in cytoplasm, it was expressed in nucleus (activated) in 60.8%. Meanwhile, STAT5 was found overexpressed in 41.3% in cytoplasm and 32.6% in nucleus. Thus, Bcl-xL was overexpressed in cytoplasm in 81.5%. Interestingly, we found nuclear expression of Bcl-xL in 30.4% of cases. Finally, we found correlation among histological types of lung cancer and nuclear expression of both STAT5 (P=0.005) and nuclear Bcl-xL (P=0.003). Besides, nuclear expression of Bcl-xL was correlated with TNM stage IV (distant metastasis) (P=0.02). These results suggest for the first time, a relevant role for STAT5 and Bcl-xL as apoptosis-regulatory proteins in the pathogenesis of lung cancer, and overexpression of both Neu and activated STAT3, could be related with the proliferation rate in lung carcinoma cells.


Assuntos
Neoplasias Pulmonares/metabolismo , Receptor ErbB-2/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Proteína bcl-X/metabolismo , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/patologia , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos
6.
Ginecol Obstet Mex ; 65: 282-6, 1997 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-9312515

RESUMO

The ovarian cystoadenofibroma are tumors not very frequently of superficial epithelium. It can appears at all ages. It can form fibrotic nodules of strong consistency that initially appear with the papillae and it forms nodule when the time goes by; generally, they are unilateral. We studied 10 cases of cystoadenofibromas in a period of 5 years, the patients' age was from 18 to 68 years old being more frequent in the adult age; seven cases were unilateral, three were bilateral, two of these appeared clinically as acute abdomen due to rupture of the tumor the third one was a hysterectomy is finding. In seven cases there was association with uterine leiomiomatosis mainly in older patients. Macroscopically it was seen that in younger patients these tumors were cystic with small papillae, and in older patients they formed fibrotic nodules. The immunohystochemical study with Vimentin and Desmin showed that the Desmin was focally immunopositive in form of fine fibers at the union with superficial epithelium and greatly positive fibrous portion for Vimentina.


Assuntos
Cistadenoma/patologia , Neoplasias Ovarianas/patologia , Adulto , Cistadenoma/cirurgia , Feminino , Hospitais Gerais , Humanos , Histerectomia , México , Pessoa de Meia-Idade , Neoplasias Ovarianas/cirurgia , Ovariectomia , Ovário/patologia
7.
Ginecol Obstet Mex ; 62: 384-8, 1994 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-7835737

RESUMO

Forty two cases of advanced gestational choriocarcinoma were examined, with 4 of these patients being hospitalized for less than 24 hours. Given the non specific and atypical nature of the symptomatology, it was correctly diagnosed in 20 of these cases. In the other 22 cases where the predominant clinical status was established as a result of the localized invasion of neighboring structures or through metastasis, a variety of diagnoses were given, including uterine cervical carcinoma, endometrial carcinoma, pulmonary metastasis, brain tumor, bleeding of the gastrointestinal tract. The 20 patient diagnosed with choriocarcinoma were treated in the following manner: nine were operated for hysterectomies, with one of these also receiving an omentectomy, seven more were given chemotherapy treatment based upon methotrexate, and the remaining for were simply stabilized, which produced unfavorable results in that they survived from one to twenty weeks longer, with an average on only five weeks.


Assuntos
Coriocarcinoma/patologia , Neoplasias Uterinas/patologia , Adolescente , Adulto , Autopsia , Coriocarcinoma/diagnóstico , Coriocarcinoma/mortalidade , Diagnóstico Diferencial , Feminino , Humanos , Histerectomia , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Metástase Neoplásica , Omento/cirurgia , Gravidez , Neoplasias Uterinas/diagnóstico , Neoplasias Uterinas/mortalidade , Útero/patologia
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