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1.
PLoS One ; 16(5): e0251134, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33945577

RESUMO

The efficacy and non-target arthropod effects of transgenic DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 Bt cotton, expressing proteins Cry1Ac, Cry1F and Vip3Aa19, was examined through field trials in Brazil. Fifteen field efficacy experiments were conducted from 2014 through the 2020 growing season across six different states in Brazil to evaluate performance against key lepidopteran pests through artificial infestations of Chrysodeixis includens (Walker), Spodoptera frugiperda (J.E. Smith,1797), Spodoptera cosmioides (Walker, 1858) and Chloridea virescens (F., 1781), and natural infestations of Alabama argillacea (Hübner) and S. frugiperda. The impact of this Bt cotton technology on the non-target arthropod community in Brazilian cotton production systems was also assessed in a multi-site experiment. DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 cotton significantly reduced the feeding damage caused by S. frugiperda, S. cosmioides, C. includens, C. virescens and A. argillacea, causing high levels of mortality (greater than 99%) to all target lepidopteran pests evaluated during vegetative and/or reproductive stages of crop development. Non-target arthropod community-level analyses confirmed no unintended effects on the arthropod groups monitored. These results demonstrate the value of transgenic Bt cotton containing event DAS-21023-5 × DAS-24236-5 × SYN-IR102-7 for consideration as part of an integrated approach for managing key lepidopteran pests in Brazilian cotton production systems.


Assuntos
Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/análogos & derivados , Artrópodes/crescimento & desenvolvimento , Gossypium/metabolismo , Gossypium/parasitologia , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/metabolismo , Animais , Brasil , Controle de Insetos , Larva/crescimento & desenvolvimento , Mariposas/crescimento & desenvolvimento , Controle Biológico de Vetores/métodos , Folhas de Planta/parasitologia , Plantas Geneticamente Modificadas/parasitologia , Spodoptera/crescimento & desenvolvimento
2.
J Econ Entomol ; 112(2): 803-811, 2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30561710

RESUMO

Field studies across four states in maize-producing areas of Brazil were conducted to characterize the efficacy of a new pyramided Bacillus thuringiensis (Bt) Berliner technology in maize, Zea mays L., and compare it to existing single and pyramided commercial Bt technologies, to control Helicoverpa zea Boddie (Lepidoptera: Noctuidae), Elasmopalpus lignosellus Zeller (Lepidoptera: Pyralidae), Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), and Diatraea saccharalis F. (Lepidoptera: Crambidae). Bt maize expressing Vip3Aa20 protein and pyramided Bt maize expressing proteins Cry1F + Cry1A.105 + Cry2Ab2 + Vip3Aa20 provided excellent protection against kernel feeding by H. zea compared to Bt technologies expressing only Cry1F or Cry1A.105 + Cry2Ab2. Bt maize expressing Cry1F, Cry1A.105 + Cry2Ab2, Cry1F + Cry1A.105 + Cry2Ab2, and Cry1F + Cry1A.105 + Cry2Ab2 + Vip3Aa20 resulted in less than 5% of plants injured by E. lignosellus, significantly less than Bt maize expressing only Vip3Aa20 and a non-Bt maize iso-hybrid with and without a thiamethoxam seed treatment. The highest protection against plant cutting injury caused by A. ipsilon was observed in the pyramid Bt maize technology expressing Cry1F + Cry1A.105 + Cry2Ab2 + Vip3Aa20. However, it did not differ statistically from the Bt maize expressing Vip3Aa20, Cry1F, or Cry1F + Cry1A.105 + Cry2Ab2. All Bt maize hybrids evaluated in our study were highly effective in reducing tunneling injury caused by D. saccharalis. These results show that a new maize technology expressing pyramided Bt proteins Cry1F + Cry1A.105 + Cry2Ab2 + Vip3Aa20 offers a higher level of protection from feeding by the above lepidopteran pest complex compared to maize with a single Bt protein or double pyramided Bt proteins.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Proteínas de Bactérias , Brasil , Endotoxinas , Proteínas Hemolisinas , Larva , Plantas Geneticamente Modificadas , Zea mays
3.
PLoS One ; 13(2): e0191567, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29394266

RESUMO

Field-scale studies that examine the potential for adverse effects of Bt crop technology on non-target arthropods may supplement data from laboratory studies to support an environmental risk assessment. A three year field study was conducted in Brazil to evaluate potential for adverse effects of cultivating soybean event DAS-81419-2 that produces the Cry1Ac and Cry1F proteins. To do so, we examined the diversity and abundance of non-target arthropods (NTAs) in Bt soybean in comparison with its non-Bt near isoline, with and without conventional insecticide applications, in three Brazilian soybean producing regions. Non-target arthropod abundance was surveyed using Moericke traps (yellow pan) and pitfall trapping. Total abundance (N), richness (S), Shannon-Wiener (H'), Simpson's (D) and Pielou's evenness (J) values for arthropod samples were calculated for each treatment and sampling period (soybean growth stages). A faunistic analysis was used to select the most representative NTAs which were used to describe the NTA community structure associated with soybean, and to test for effects due to the treatments effects via application of the Principal Response Curve (PRC) method. Across all years and sites, a total of 254,054 individuals from 190 taxa were collected by Moericke traps, while 29,813 individuals from 100 taxa were collected using pitfall traps. Across sites and sampling dates, the abundance and diversity measurements of representative NTAs were not significantly affected by Bt soybean as compared with non-sprayed non-Bt soybean. Similarly, community analyses and repeated measures ANOVA, when applicable, indicated that neither Bt soybean nor insecticide sprays altered the structure of the NTA communities under study. These results support the conclusion that transgenic soybean event DAS-81419-2 producing Cry1Ac and Cry1F toxins does not adversely affect the NTA community associated with soybean.


Assuntos
Artrópodes/efeitos dos fármacos , Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas/genética , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/farmacologia , Brasil , Endotoxinas/farmacologia , Proteínas Hemolisinas/farmacologia
4.
Rev. Fac. Cienc. Méd. Univ. Cuenca ; 31(2): 62-67, Julio 2013. tab
Artigo em Espanhol | LILACS | ID: biblio-1006057

RESUMO

El estudio tiene como finalidad establecer la sensibilidad, la especificidad, el valor predictivo positivo, y el valor predictivo negativo de la monitorización cardiotocográfica fetal, para diagnóstico de Sufrimiento Fetal Agudo y que llevan a la terminación de la gestación por cesárea de emergencia, comparado con el test de Apgar del recién nacido tomado como GOLD STANDARD. El universo de estudio consistió en 880 pacientes embarazadas a quienes se les realizó cesárea, se obtuvo una muestra de 110 recién nacidos. De ellos 46 fueron diagnosticados de Sufrimiento Fetal Agudo con la prueba de oro, Apgar al minuto < de 7, y 64 como normales, Apgar al minuto ≥ a 7. En el estudio se encontró que la sensibilidad de la Monitorización cardiotocográfica fetal fue del 21,7% (IC 95% 12.26, 35.57¹). Y la especificidad de la Monitorización cardiotocográfica fetal fue del 84.4% (IC 95% 73.57, 91.29¹). Se concluyó que la Monitorización cardiotocográfica fetal, nos ayuda más como prueba para valorar bienestar fetal, sobre todo en embarazos de alto riesgo obstétrico, pero en sí es poco sensible para detectar que un feto se encuentra con Sufrimiento Fetal Agudo.


This study is attained to establish the sensibility, specificity, positive predictive value, and negative predictive value, of the fetal cardiotocographic monitoring for the diagnosis of acute fetal suffering wich leads to the termination of the gestation with in an emergency cesarean surgery, compared to the APGAR test of the new born as a Gold Standard. The universe of the study consisted in 880 pregnant women to whom a cesarean surgery was made. A 110 new born sample was obtained. 46 of them were diagnosed with acute fetal suffering with Gold Standard test; with an Apgar test < 7 at the first minute, 64 were normal with an Apgar test ≥ 7. This study found that the sensibility of the fetal cardiotocographic monitoring was 21.7% (IC 95% 12.26, 35.57¹).), and the specificity was 84.4% (IC 95% 73.57, 91.29¹). The conclusion was that the fetal cardiotocographic monitoring helps more as a test to value fetal well-being, above everything in high obstetrics risk pregnancies, the test is pretty less sensitive to detect that a fetus is coursing acute fetal suffering.


Assuntos
Humanos , Feminino , Gravidez , Cardiotocografia , Cesárea , Monitorização Fetal , Valor Preditivo dos Testes , Diagnóstico , Sofrimento Fetal
5.
Exp Cell Res ; 317(12): 1677-88, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21565189

RESUMO

We have previously demonstrated that a proapoptotic cyclic peptide CIGB-300, formerly known as P15-Tat delivered into the cells by the cell-penetrating peptide Tat, was able to abrogate the CK2-mediated phosphorylation and induce tumor regression when injected directly into solid tumors in mice or by systemic administration. In this work, we studied the role of CIGB-300 on the main events that take place in angiogenesis. At non-cytotoxic doses, CIGB-300 was able to inhibit adhesion, migration, and tubular network formation induced by human umbilical vein endothelial cells (HUVEC) growing upon Matrigel in vitro. Likewise, we evaluated the cellular penetration and localization into the HUVEC cells of CIGB-300. Our results confirmed a quick cellular penetration and a cytoplasmic accumulation in the early minutes of incubation and a translocation into the nuclei beginning at 12h of treatment, with a strong presence in the perinuclear area. A microarray analysis was used to determine the genes affected by the treatment. We observed that CIGB-300 significantly decreased four genes strongly associated with tubulogenesis, growth, and differentiation of endothelial cells. The CIGB-300 was tested in vivo on chicken embryo chorioallantoic membranes (CAM), and a large number of newly formed blood vessels were significantly regressed. The results suggested that CIGB-300 has a potential as an antiangiogenic treatment. The mechanism of action may be associated with partial inhibition of VEGF and Notch pathways.


Assuntos
Inibidores da Angiogênese/farmacologia , Apoptose/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Endotélio Vascular/efeitos dos fármacos , Neovascularização Patológica/prevenção & controle , Peptídeos Cíclicos/farmacologia , Animais , Biomarcadores/metabolismo , Western Blotting , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Perfilação da Expressão Gênica , Humanos , Técnicas In Vitro , Análise de Sequência com Séries de Oligonucleotídeos , Veias Umbilicais/citologia , Veias Umbilicais/efeitos dos fármacos , Veias Umbilicais/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
6.
J Econ Entomol ; 103(4): 1180-6, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20857726

RESUMO

The Mexican rice borer, Eoreuma loftini (Dyar) (Lepidoptera: Crambidae), a key pest of sugarcane (Saccharum spp.) and rice, Oryza sativa L., in Texas, has not been controlled with chemical insecticides or biological agents, but some sugarcane varieties have shown degrees of resistance. Assessment of selected sugarcane leaf characteristics indicate that preference for oviposition sites is mostly determined by the presence of a leaf fold and secondarily by the availability of dry leaf tissue, both of which are antixenotic nonchemical stimuli. We suggest that breeding sugarcane lines bearing leaves that do not fold on drying could provide substantial antixenotic resistance against the Mexican rice borer. Previously identified antixenotic chemical stimuli, i.e., low quantities or absence of important nutrients in green leaf tissue, only become apparent when resistant and susceptible sugarcane varieties are compared. Varietal differences in oviposition preference, however, were not observed on excised dry leaf tissue, indicating that expression of resistance in terms of chemical stimuli requires detection of biochemicals in nearby living leaf tissue. Excised dry sugarcane leaves retain the two dominant nonchemical oviposition preference stimuli for Mexican rice borers, and the leaves effectively trapped eggs away from intact plants when dry leaves were used as "mulch" at the bottom of greenhouse cages. Under commercial sugarcane field conditions, bundled dry leaves also collected Mexican rice borer eggs. Possible applications of dry sugarcane leaf substrate for egg scouting and for trapping eggs are discussed.


Assuntos
Mariposas/fisiologia , Oviposição/fisiologia , Saccharum/parasitologia , Animais , Feminino , Folhas de Planta/parasitologia , Fatores de Tempo
7.
La Paz; OPS/OMS; sept.2009. [18] p. graf.
Não convencional em Espanhol | LIBOCS, LIBOSP | ID: biblio-1301798

RESUMO

Apoyar al SEDES La Paz en la réplica de la experiencia Servicios de Salud Estella en la red de servicios este de la ciudad de La Paz


Assuntos
Serviços de Saúde , Saúde de Gênero
8.
J Econ Entomol ; 97(6): 2106-16, 2004 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15666772

RESUMO

The efficacy of transgenic corn hybrids expressing an insecticidal Bacillus thuringiensis (Bt) delta-endotoxin from different transformation events was evaluated in field corn, Zea mays L., against the southwestern corn borer, Diatraea grandiosella Dyar, and sugarcane borer, Diatraea saccharalis (F.). Susceptibilities of neonates and third instars were determined on Bt and non-Bt corn plants (V6 and R1 stages) in field plots and corn leaf tissue feeding exposure in laboratory bioassays. Bt corn hybrids associated with MON810 and CBH351 transformation events sustained significantly less injury by southwestern corn borer and sugarcane borer during mid-whorl stage infestations compared with their respective non-Bt hybrid equivalents. Southwestern corn borer and sugarcane borer feeding injury to ear leaf-sheath and husk tissues during the silking stage of corn was significantly reduced in MON810 and CBH351 Bt corn compared with their respective non-Bt hybrids. However, resistance levels to feeding injury in Bt hybrids associated with the MON810 event were significantly higher than that in the hybrid associated with the CBH351 event. Southwestern corn borer and sugarcane borer caused more feeding injury to husk tissue than to ear leaf-sheath tissue in both Bt and non-Bt hybrids infested during the silking stage. Laboratory performance of the MON810 event against southwestern corn borer and sugarcane borer varied among hybrids associated with the same event. Third instars of southwestern corn borer were highly susceptible to MON810 Bt corn hybrids in leaf tissue experiments. However, sugarcane borer larvae were susceptible to the MON810 event only in one of the Bt hybrids evaluated. Sugarcane borer mortality was significantly lower after 96 h of feeding exposure on CBH351 Bt corn leaf tissue than on MON810 Bt corn leaf tissue. Plant resistance to southwestern corn borer and sugarcane borer increased as plants matured, independent of the presence of a Bt construct. These results are essential to estimate the importance of Bt transgenic corn in areas of southern United States and other areas where mixed populations of southwestern corn borer and sugarcane borer are predominant and cause severe damage to corn production.


Assuntos
Proteínas de Bactérias/genética , Toxinas Bacterianas/genética , Endotoxinas/genética , Mariposas/fisiologia , Controle Biológico de Vetores/métodos , Plantas Geneticamente Modificadas , Zea mays/genética , Animais , Toxinas de Bacillus thuringiensis , Ingestão de Alimentos , Proteínas Hemolisinas , Inseticidas , Doenças das Plantas/genética , Folhas de Planta
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