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1.
Lasers Med Sci ; 34(4): 659-666, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30250986

RESUMO

The aim of this in vitro study was to analyze the effect of photobiomodulation therapy (PBMT) on the proliferation and undifferentiating status of stem cell from human exfoliated deciduous teeth (SHEDs). PBMT was carried out with an aluminum gallium indium phosphide (InGaAlP) diode laser in contact and punctual mode (continuous wave, 660 nm, 20 mW, 0.028 cm2, and average energy densities of 1 (1 s), 3 (4 s), 5 (7 s), 10 (14 s), 15 (21 s), or 20 (28 s) J/cm2 per point). The immunoprofile of the SHEDs was analyzed using flow cytometry. Cell proliferation was assessed by the MTT reduction assay. Gene expressions of mesenchymal stem cell markers (OCT4, Nestin, CD90, and CD105) were assessed by RT-qPCR 48 h after PBMT. Data were compared by analysis of variance (ANOVA) and Tukey's test (p ≤ 0.05). Cells cultured under nutritional deficit and treated with PBMT at 5 J/cm2 presented similar cell growth than those of positive control group. Cell growth was significantly higher than those of other groups. Mesenchymal stem cell gene markers were still expressed after PBMT at 5 J/cm2. In a short-term analysis, PBMT increases the number of stem cells with no interference in the undifferentiated state of the irradiated cells, which opens wide possibilities for application in tissue regeneration.


Assuntos
Diferenciação Celular/efeitos da radiação , Polpa Dentária/citologia , Terapia com Luz de Baixa Intensidade , Células-Tronco/citologia , Células-Tronco/efeitos da radiação , Proliferação de Células/efeitos da radiação , Células Cultivadas , Regulação da Expressão Gênica/efeitos da radiação , Humanos , Lasers Semicondutores , Fatores de Tempo , Esfoliação de Dente/patologia , Dente Decíduo/citologia
2.
Nature ; 448(7154): 696-9, 2007 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-17687325

RESUMO

For numerous taxa, species richness is much higher in tropical than in temperate zone habitats. A major challenge in community ecology and evolutionary biogeography is to reveal the mechanisms underlying these differences. For herbivorous insects, one such mechanism leading to an increased number of species in a given locale could be increased ecological specialization, resulting in a greater proportion of insect species occupying narrow niches within a community. We tested this hypothesis by comparing host specialization in larval Lepidoptera (moths and butterflies) at eight different New World forest sites ranging in latitude from 15 degrees S to 55 degrees N. Here we show that larval diets of tropical Lepidoptera are more specialized than those of their temperate forest counterparts: tropical species on average feed on fewer plant species, genera and families than do temperate caterpillars. This result holds true whether calculated per lepidopteran family or for a caterpillar assemblage as a whole. As a result, there is greater turnover in caterpillar species composition (greater beta diversity) between tree species in tropical faunas than in temperate faunas. We suggest that greater specialization in tropical faunas is the result of differences in trophic interactions; for example, there are more distinct plant secondary chemical profiles from one tree species to the next in tropical forests than in temperate forests as well as more diverse and chronic pressures from natural enemy communities.


Assuntos
Dieta , Ecossistema , Lepidópteros/fisiologia , Árvores , Clima Tropical , Animais , Biodiversidade , Larva/fisiologia , Especificidade da Espécie
3.
Phys Rev Lett ; 107(22): 220501, 2011 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-22182018

RESUMO

We report the experimental realization of a hybrid quantum circuit combining a superconducting qubit and an ensemble of electronic spins. The qubit, of the transmon type, is coherently coupled to the spin ensemble consisting of nitrogen-vacancy centers in a diamond crystal via a frequency-tunable superconducting resonator acting as a quantum bus. Using this circuit, we prepare a superposition of the qubit states that we store into collective excitations of the spin ensemble and retrieve back into the qubit later on. These results constitute a proof of concept of spin-ensemble based quantum memory for superconducting qubits.

4.
Braz J Biol ; 79(2): 248-256, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29995136

RESUMO

The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p <0.05) negatively with precipitation. This study provided field information on the abundance and species richness of owlet moths on non-Bt soybeans, associated with the effects of Bt soybean. When considering the different levels of infestation between cultivars as a criterion, larvae monitoring is of substantial importance in order to develop the lost control program.


Assuntos
Proteínas de Bactérias , Endotoxinas , Glycine max , Proteínas Hemolisinas , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos , Controle Biológico de Vetores , Plantas Geneticamente Modificadas , Animais , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Brasil , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Glycine max/genética , Glycine max/parasitologia
5.
Arch Oral Biol ; 86: 101-107, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29216525

RESUMO

The impact of high-refined carbohydrate (HC) diet on fat accumulation, adipokines secretion and systemic inflammation is well described. However, it remains unclear whether these processes affect bone remodeling. OBJECTIVE: To investigate the effects of HC diet in the alveolar bone and femur parameters. METHODS: BalbC mice were fed with conventional chow or HC diet for 12 weeks. After experimental time maxillae, femur, blood and white adipose tissue samples were collected. RESULTS: The animals feed with HC diet exhibited considerable increase of adiposity index and adipose tissue levels of TNF-α, IL-6, IL-10, IL-1ß, TGF-ß and leptin. Microtomography analysis of maxillary bone revealed horizontal alveolar bone loss and disruption of trabecular bone in mice feed with HC diet. These deleterious effects were correlated with a disturbance in bone cells and an augmented expression of Rankl/Opg ratio. Consistently, similar effects were observed in femurs, which also exhibited a reduction in bone maximum load and stiffness. CONCLUSION: Our data indicates that HC diet consumption disrupts bone remodeling process, favoring bone loss. Underlying mechanisms relies on fat tissue accumulation and also in systemic and local inflammation.


Assuntos
Tecido Adiposo/metabolismo , Processo Alveolar/metabolismo , Dieta da Carga de Carboidratos , Fêmur/metabolismo , Maxila/metabolismo , Processo Alveolar/diagnóstico por imagem , Animais , Biomarcadores/sangue , Remodelação Óssea , Citocinas/sangue , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Fêmur/diagnóstico por imagem , Inflamação/etiologia , Inflamação/metabolismo , Masculino , Maxila/diagnóstico por imagem , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase , Estresse Mecânico , Microtomografia por Raio-X
6.
Braz. j. biol ; 79(2): 248-256, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-989445

RESUMO

Abstract The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p <0.05) negatively with precipitation. This study provided field information on the abundance and species richness of owlet moths on non-Bt soybeans, associated with the effects of Bt soybean. When considering the different levels of infestation between cultivars as a criterion, larvae monitoring is of substantial importance in order to develop the lost control program.


Resumo O uso de OGM que expressam toxina Bt na produção de soja tem aumentado significativamente nos últimos anos no Brasil e são utilizados para conter os danos causados ​​pelos lepidópteros pragas. Neste estudo comparamos a riqueza e a abundância de Noctuoides (Noctuoidea) associados à soja Bt e não-Bt. Determinamos as variações temporais em função da fenologia e correlacionamos às variações populacionais das espécies mais comuns com variáveis ​​meteorológicas. A pesquisa foi conduzida na área experimental da Embrapa Cerrados. O método de coleta utilizado foi diferenciado sendo supressivo e absoluto. Um total de 13 espécies foram coletadas, das quais oito ocorreram em soja Bt. Os taxa mais representativos foram Chrysodeixis includens, Anticarsia gemmatalis e Spodoptera spp. O número de larvas pertencentes às espécies alvo da tecnologia Bt foram 10 vezes menores na soja Bt do que em soja não-Bt . Utetheisa ornatrix e Elaphria deltoides foram registradas na soja pela primeira vez, observando-se larvas de ambas espécies na soja não-Bt e as de U. ornatrix também na soja Bt. Somente as larvas de A. gemmatalis se correlacionaram (p <0,05) negativamente com a precipitação. Este estudo forneceu informações em campo sobre a abundância e riqueza de espécies na soja não- Bt, associada aos efeitos da soja Bt. A importância do monitoramento das lagartas é substancial, a fim de tomar a melhor decisão de controle, considerando-se os diferentes níveis de infestação entre cultivares como critério.


Assuntos
Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/farmacologia , Endotoxinas/genética , Endotoxinas/farmacologia , Proteínas Hemolisinas/genética , Proteínas Hemolisinas/farmacologia , Glycine max/genética , Glycine max/parasitologia , Brasil , Controle Biológico de Vetores , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/parasitologia , Larva/efeitos dos fármacos , Mariposas/efeitos dos fármacos
7.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1467179

RESUMO

Abstract The use of GMO expressing Bt toxin in soybean production has increased significantly in the last years in Brazil in order to manage the damage caused by lepidopteran pests. In this study, we compared the richness and abundance of owlet moths (Noctuoidea) associated with Bt and non-Bt soybean. We determined the temporal variations as a function of phenology, and correlated the population variations of the most common species with meteorological variables. The research was conducted at the experimental area of Embrapa Cerrados. The collection method used was differentiated being suppressive and absolute. A total of 13 species were collected, of which eight occurred on Bt soybeans. The most representative taxa were Chrysodeixis includens (72.87%), Anticarsia gemmatalis (18.17%) and Spodoptera spp (5.22%). The number of larvae belonging to species targeted by the Bt technology was 10 times lower on Bt than on non-Bt soybeans. Utetheisa ornatrix and Elaphria deltoides were recorded on soybean for the first time, observing larvae of both species in non-Bt soybean and those of U. ornatrix also in Bt soybean. Only A. gemmatalis larvae correlated (p 0.05) negatively with precipitation. This study provided field information on the abundance and species richness of owlet moths on non-Bt soybeans, associated with the effects of Bt soybean. When considering the different levels of infestation between cultivars as a criterion, larvae monitoring is of substantial importance in order to develop the lost control program.


Resumo O uso de OGM que expressam toxina Bt na produção de soja tem aumentado significativamente nos últimos anos no Brasil e são utilizados para conter os danos causados pelos lepidópteros pragas. Neste estudo comparamos a riqueza e a abundância de Noctuoides (Noctuoidea) associados à soja Bt e não-Bt. Determinamos as variações temporais em função da fenologia e correlacionamos às variações populacionais das espécies mais comuns com variáveis meteorológicas. A pesquisa foi conduzida na área experimental da Embrapa Cerrados. O método de coleta utilizado foi diferenciado sendo supressivo e absoluto. Um total de 13 espécies foram coletadas, das quais oito ocorreram em soja Bt. Os taxa mais representativos foram Chrysodeixis includens, Anticarsia gemmatalis e Spodoptera spp. O número de larvas pertencentes às espécies alvo da tecnologia Bt foram 10 vezes menores na soja Bt do que em soja não-Bt . Utetheisa ornatrix e Elaphria deltoides foram registradas na soja pela primeira vez, observando-se larvas de ambas espécies na soja não-Bt e as de U. ornatrix também na soja Bt. Somente as larvas de A. gemmatalis se correlacionaram (p 0,05) negativamente com a precipitação. Este estudo forneceu informações em campo sobre a abundância e riqueza de espécies na soja não- Bt, associada aos efeitos da soja Bt. A importância do monitoramento das lagartas é substancial, a fim de tomar a melhor decisão de controle, considerando-se os diferentes níveis de infestação entre cultivares como critério.

8.
Braz J Biol ; 70(1): 103-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20231965

RESUMO

Folivore cerrado caterpillars are found on their host species in low frequencies, which vary between plants and throughout the year. We analysed the effects of climatic variation and of the characteristics of two host species (Miconia, Melastomataceae) on caterpillar abundance. The work was carried out in a cerrado sensu stricto area in Brasília, Federal District, Brazil, from May 1998 to September 1999. One hundred plants of each species were inspected monthly. All caterpillars found were collected and raised in the laboratory with Miconia leaves as food sources. Climatic data for the study area and plant characteristics such as local density, spatial distribution, foliar phenology, leaf pilosity and nutritional content were used to test the effects on caterpillar abundance. Less than 10% of the plants had larvae. Caterpillars were more frequent and abundant in M. pohliana, which was also present at higher densities than M. ferruginata. Low caterpillar frequency in host plants and an abundance peak during the dry season are consistent patterns for different cerrado Lepidoptera larvae. This abundance peak, however, is not coincident with higher leaf production in host species. We suggest that M. pohliana's higher local density and better leaf digestibility can account for the higher abundance of caterpillars in this species.


Assuntos
Comportamento Alimentar/fisiologia , Lepidópteros/fisiologia , Melastomataceae/parasitologia , Animais , Interações Hospedeiro-Parasita/fisiologia , Folhas de Planta/parasitologia , Densidade Demográfica , Estações do Ano
9.
Proc Natl Acad Sci U S A ; 102(48): 17384-7, 2005 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-16293686

RESUMO

Insect outbreaks are expected to increase in frequency and intensity with projected changes in global climate through direct effects of climate change on insect populations and through disruption of community interactions. Although there is much concern about mean changes in global climate, the impact of climatic variability itself on species interactions has been little explored. Here, we compare caterpillar-parasitoid interactions across a broad gradient of climatic variability and find that the combined data in 15 geographically dispersed databases show a decrease in levels of parasitism as climatic variability increases. The dominant contribution to this pattern by relatively specialized parasitoid wasps suggests that climatic variability impairs the ability of parasitoids to track host populations. Given the important role of parasitoids in regulating insect herbivore populations in natural and managed systems, we predict an increase in the frequency and intensity of herbivore outbreaks through a disruption of enemy-herbivore dynamics as climates become more variable.


Assuntos
Efeito Estufa , Lepidópteros/parasitologia , Vespas/fisiologia , Animais , Geografia , Interações Hospedeiro-Parasita , Larva/parasitologia , Larva/fisiologia , Lepidópteros/fisiologia , Dinâmica Populacional , Análise de Regressão
10.
Rev Bras Biol ; 59(4): 627-35, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23505651

RESUMO

Nine lactiferous plants of five families were examined for caterpillars in a 4 ha cerrado sensu stricto (savanna-like vegetation) area of the University of Brasília Experimental Farm (DF, Brazil), from August 1995 to May 1997. In 5,540 censuses, less than 5% of the plants hosted caterpillars. All the caterpillars found, a total of 55 species in 15 families were reared under laboratory conditions. Pyralidae, Geometridae, Elachistidae, Megalopygidae, and Limacodidae were the richest caterpillar families recorded. Of the 55 species, more than 40% were polyphagous, feeding on different host plant families, while 21 were considered rare species with less than four records during the study period. The species' rareness did not permit any analysis of diet breadth. The presence of latex in the host plants seems to affect both the proportion of host plants with caterpillars (abundance) and the caterpillar species richness. The habit of eating plants that characteristically produce latex occurs in several distantly-related lepidopteran families. The results support the argument that specific behaviors to circumvent plant latex defense may have arisen independently many times in the Lepidoptera.


Assuntos
Lepidópteros , Plantas , Animais , Ecossistema , Larva/classificação , Larva/crescimento & desenvolvimento , Látex , Lepidópteros/classificação , Lepidópteros/crescimento & desenvolvimento , Densidade Demográfica
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