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1.
Proc Natl Acad Sci U S A ; 109(37): E2451-6, 2012 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-22908279

RESUMO

Based on previously published hydroponic plant, planktonic bacterial, and soil microbial community research, manufactured nanomaterial (MNM) environmental buildup could profoundly alter soil-based food crop quality and yield. However, thus far, no single study has at once examined the full implications, as no studies have involved growing plants to full maturity in MNM-contaminated field soil. We have done so for soybean, a major global commodity crop, using farm soil amended with two high-production metal oxide MNMs (nano-CeO(2) and -ZnO). The results provide a clear, but unfortunate, view of what could arise over the long term: (i) for nano-ZnO, component metal was taken up and distributed throughout edible plant tissues; (ii) for nano-CeO(2), plant growth and yield diminished, but also (iii) nitrogen fixation--a major ecosystem service of leguminous crops--was shut down at high nano-CeO(2) concentration. Juxtaposed against widespread land application of wastewater treatment biosolids to food crops, these findings forewarn of agriculturally associated human and environmental risks from the accelerating use of MNMs.


Assuntos
Qualidade dos Alimentos , Glycine max/efeitos dos fármacos , Nanoestruturas/toxicidade , Fixação de Nitrogênio/efeitos dos fármacos , Poluentes do Solo/toxicidade , Agricultura , Cério , Cromatografia Gasosa , Fertilidade , Espectrometria de Massas , Microscopia Eletrônica , Nanotecnologia/tendências , Poluentes do Solo/farmacocinética , Glycine max/crescimento & desenvolvimento , Espectroscopia por Absorção de Raios X , Óxido de Zinco
2.
Sci Total Environ ; 579: 1756-1768, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27939199

RESUMO

With increasing use, manufactured nanomaterials (MNMs) may enter soils and impact agriculture. Herein, soybean (Glycine max) was grown in soil amended with either nano-CeO2 (0.1, 0.5, or 1.0gkg-1 soil) or nano-ZnO (0.05, 0.1, or 0.5gkg-1 soil). Leaf chlorosis, necrosis, and photosystem II (PSII) quantum efficiency were monitored during plant growth. Seed protein and protein carbonyl, plus leaf chlorophyll, reactive oxygen species (ROS), lipid peroxidation, and genotoxicity were measured for plants at harvest. Neither PSII quantum efficiency, seed protein, nor protein carbonyl indicated negative MNM effects. However, increased ROS, lipid peroxidation, and visible damage, along with decreased total chlorophyll concentrations, were observed for soybean leaves in the nano-CeO2 treatments. These effects correlated to aboveground leaf, pod, and stem production, and to root nodule N2 fixation potential. Soybeans grown in soil amended with nano-ZnO maintained growth, yield, and N2 fixation potential similarly to the controls, without increased leaf ROS or lipid peroxidation. Leaf damage was observed for the nano-ZnO treatments, and genotoxicity appeared for the highest nano-ZnO treatment, but only for one plant. Total chlorophyll concentrations decreased with increasing leaf Zn concentration, which was attributable to zinc complexes-not nano-ZnO-in the leaves. Overall, nano-ZnO and nano-CeO2 amended to soils differentially triggered aboveground soybean leaf stress and damage. However, the consequences of leaf stress and damage to N2 fixation, plant growth, and yield were only observed for nano-CeO2.


Assuntos
Cério/toxicidade , Glycine max/fisiologia , Nanoestruturas/toxicidade , Poluentes do Solo/toxicidade , Óxido de Zinco/toxicidade , Clorofila/metabolismo , Peroxidação de Lipídeos , Folhas de Planta , Raízes de Plantas , Espécies Reativas de Oxigênio/metabolismo , Solo , Glycine max/efeitos dos fármacos , Glycine max/crescimento & desenvolvimento
3.
Plant Sci ; 252: 76-87, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27717480

RESUMO

We have identified a viable-yellow and a lethal-yellow chlorophyll-deficient mutant in soybean. Segregation patterns suggested single-gene recessive inheritance for each mutant. The viable- and lethal-yellow plants showed significant reduction of chlorophyll a and b. Photochemical energy conversion efficiency and photochemical reflectance index were reduced in the viable-yellow plants relative to the wildtype, whereas the lethal-yellow plants showed no electron transport activity. The viable-yellow plants displayed reduced thylakoid stacking, while the lethal-yellow plants exhibited failure of proplastid differentiation into normal chloroplasts with grana. Genetic analysis revealed recessive epistatic interaction between the viable- and the lethal-yellow genes. The viable-yellow gene was mapped to a 58kb region on chromosome 2 that contained seven predicted genes. A frame shift mutation, due to a single base deletion in Glyma.02g233700, resulted in an early stop codon. Glyma.02g233700 encodes a translocon in the inner membrane of chloroplast (GmTic110) that plays a critical role in plastid biogenesis. The lethal-yellow gene was mapped to an 83kb region on chromosome 3 that contained 13 predicted genes. Based on the annotated functions, we sequenced three potential candidate genes. A single base insertion in the second exon of Glyma.03G230300 resulted in a truncated protein. Glyma.03G230300 encodes for GmPsbP, an extrinsic protein of Photosystem II that is critical for oxygen evolution during photosynthesis. GmTic110 and GmPsbP displayed highly reduced expression in the viable- and lethal-yellow mutants, respectively. The yellow phenotypes in the viable- and lethal-yellow mutants were due to the loss of function of GmTic110 or GmPsbP resulting in photooxidative stress.


Assuntos
Clorofila/fisiologia , Cloroplastos/genética , Glycine max/genética , Clorofila/genética , Clorofila/metabolismo , Cloroplastos/metabolismo , Cloroplastos/fisiologia , Mapeamento Cromossômico , Cromossomos de Plantas , Análise Mutacional de DNA , Epistasia Genética , Genes Recessivos , Mutação , Complexo de Proteína do Fotossistema II/genética , Glycine max/metabolismo , Glycine max/fisiologia
4.
VozAndes ; 17(1): 24-26, 2006.
Artigo em Espanhol | LILACS | ID: biblio-1100645

RESUMO

La patología quirúrgica del epiplón mayor es muy rara e incluye torsión, infarto, quistes y tumores al rededor del 85% de los casos han sido reportados en población adulta, el restante 15% en población pediátrica. debido a la sintomatología no específica el diagnóstico preoperatorio es frecuentemente confundido con apendicitis aguda porque es la causa más frecuente de dolor abdominal. El presente artículo describe el caso clínico de un paciente adulto con torsión e infarto de omento, el cual fue diagnosticado y tratado en nuestro hospital por cirugía laparoscópia.


Surgical pathology of the greater omentum is very rare and includes torsion, infarction, cysts and tumors. About 85% of cases have been reported in the adult population, the remaining 15% in the pediatric population. Due to nonspecific symptoms, preoperative diagnosis is frequently confused with acute appendicitis because it is the most frequent cause of abdominal pain. This article describes the clinical case of an adult patient with torsion and omentum infarction, who was diagnosed and treated in our hospital by laparoscopic surgery.


Assuntos
Humanos , Masculino , Feminino , Criança , Adulto , Omento , Dor Abdominal , Infarto , Patologia Cirúrgica , Cistos , Neoplasias
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