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1.
J Insect Sci ; 20(4)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32770251

RESUMO

Aphidophagous syrphids (Diptera: Syrphidae) are important insects in agroecosystems for pollination and biological control. Insect chemoreception is essential for these processes and for insect survival and reproduction; however, molecular determinants is not well understood for these beneficial insects. Here, we used recent transcriptome data for the common hoverfly, Episyrphus balteatus, to characterize key molecular components of chemoreception: odorant-binding proteins (OBPs) and chemosensory proteins (CSPs). Six EbalCSPs and 44 EbalOBPs were cloned from this species, and sequence analysis showed that most share the characteristic hallmarks of their protein family, including a signal peptide and conserved cysteine signature. Some regular patterns and key conserved motifs of OBPs and CSPs in Diptera were identified using the online tool MEME. Motifs were also compared among the three OBP subgroups. Quantitative real-time PCR (qRT-PCR) showed that most of these chemosensory genes were expressed in chemosensory organs, suggesting these genes have chemoreceptive functions. An overall comparison of the Ka/Ks values of orthologous genes in E. balteatus and another predatory hoverfly species to analyze the evolution of these olfactory genes showed that OBPs and CSPs are under strong purifying selection. Overall, our results provide a molecular basis for further exploring the chemosensory mechanisms of E. balteatus, and consequently, may help us to understand the tritrophic interactions among plants, herbivorous insects, and natural enemies.


Assuntos
Dípteros/genética , Evolução Molecular , Proteínas de Insetos/genética , Receptores Odorantes/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Dípteros/metabolismo , Feminino , Perfilação da Expressão Gênica , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Masculino , Receptores Odorantes/química , Receptores Odorantes/metabolismo
2.
J Insect Physiol ; 113: 49-58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30080999

RESUMO

Aphidophagous syrphids are important for pest control and pollination in various agroecosystems. However, the mechanism underlying olfaction, which is critical for insect' behavioral processes and fitness, has not been well understood in the family Syrphidae. Hence, we performed a systematic identification and characterisation of the antennal sensilla and two groups of soluble proteins, odorant-binding proteins (OBPs) and chemosensory proteins (CSPs), in the hoverfly Eupeodes corollae. (i) With scanning electron microscopy, four major types of sensilla (chaetic sensilla [two subtypes], trichoid sensilla, basiconic sensilla [two subtypes] and coeloconic sensilla), with numerous microtrichia, were first observed along the entire surface of aristate antennae of both sexes of E. corollae. Of these, only chaetic sensillum was found on the first two antennal segments, scape and pedicel, while the other types of sensilla were located on the flagellum. No marked difference was observed in the morphological structure or distributional pattern of any of the sensilla between the two sexes. (ii) By molecular cloning and bioinformatic analysis, 7 EcorCSPs and 28 EcorOBPs (20 classic OBPs, 5 minus-C OBPs, and 3 plus-C OBPs) were directly identified from the species, which all share the characteristic hallmarks of their family, including the presence of a signal peptide and conserved cysteine signature. (iii) RT-qPCR of these chemosensory genes showed predominately tissue-biased expression patterns; 32 of the 35 EcorOBPs/CSPs were uniquely or primarily expressed in the main olfactory organs, either the antennae or head. (iv) Among these, several genes (EcorCSP2 and EcorOBP1, 9, 12, 15-17, 20) appeared to be antenna-biased. In situ hybridization assays indicated that each antenna-biased chemosensory gene was expressed in a different number of cells, suggesting they might play a more vital role in odour recognition and perception and could be potential candidates to study their biological functions in vivo and in vitro. Together, our current findings provide a basis for future studies on how syrphids utilize chemical cues to regulate their behavior during interactions among the natural enemy, its prey, and host plant in agro-ecosystems.


Assuntos
Proteínas de Transporte/genética , Dípteros/genética , Dípteros/ultraestrutura , Proteínas de Insetos/genética , Receptores Odorantes/genética , Sensilas/ultraestrutura , Sequência de Aminoácidos , Animais , Proteínas de Transporte/metabolismo , Feminino , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Percepção Olfatória , Filogenia , Receptores Odorantes/química , Receptores Odorantes/metabolismo , Alinhamento de Sequência
3.
Radiol Case Rep ; 12(2): 300-303, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28491175

RESUMO

Tubal choriocarcinoma is uncommon, and its magnetic resonance imaging characteristics have not yet been reported. In this report, a 39-year-old woman presented with irregular painless vaginal bleeding and a palpable left lower abdominal lump for 2 months following 6 weeks' amenorrhea and positive urine pregnancy test. Her serum ß-human chorionic gonadotropin value was significantly increased. Ultrasound revealed a left adnexal mass, which showed no blood flow signal on Color doppler flow imaging. A further MR examination showed a well-defined cystic-solid mass with cystic component accounting for a large proportion in the left lower abdomen. The solid part with mixed signals resembled a honeycomb. Finally, the left tubal choriocarcinoma was confirmed by pathology. When the solid parts of cystic-solid mass appeared as "honeycomb appearance" and the ovaries were normal by magnetic resonance imaging, together with typical symptoms and significantly elevated ß-human chorionic gonadotropin values, radiologists should feel more confident in suspecting tubal choriocarcinoma and reporting it on their differential.

4.
Sci Rep ; 7: 41688, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28139751

RESUMO

Cry1Ie protein derived from Bacillus thuringiensis (Bt) has been proposed as a promising candidate for the development of a new Bt-maize variety to control maize pests in China. We studied the response of the midgut bacterial community of Apis cerana cerana to Cry1Ie toxin under laboratory conditions. Newly emerged bees were fed one of the following treatments for 15 and 30 days: three concentrations of Cry1Ie toxin (20 ng/mL, 200 ng/mL, and 20 µg/mL) in sugar syrup, pure sugar syrup as a negative control and 48 ng/mL imidacloprid as a positive control. The relative abundance of 16S rRNA genes was measured by Quantitative Polymerase Chain Reaction and no apparent differences were found among treatments for any of these counts at any time point. Furthermore, the midgut bacterial structure and compositions were determined using high-throughput sequencing targeting the V3-V4 regions of the 16S rDNA. All core honey bee intestinal bacterial genera such as Lactobacillus, Bifidobacterium, Snodgrassella, and Gilliamella were detected, and no significant changes were found in the species diversity and richness for any bacterial taxa among treatments at different time points. These results suggest that Cry1Ie toxin may not affect gut bacterial communities of Chinese honey bees.


Assuntos
Toxinas Bacterianas/farmacologia , Abelhas/efeitos dos fármacos , Abelhas/microbiologia , Biodiversidade , Microbioma Gastrointestinal/efeitos dos fármacos , Animais , Bacillus thuringiensis , Análise por Conglomerados , Metagenoma , Metagenômica/métodos , RNA Ribossômico 16S/genética
5.
J Econ Entomol ; 109(6): 2259-2263, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-27670271

RESUMO

The cry1Ie gene may be a good candidate for the development of Bt maize because over-expression of Cry1Ie is highly toxic to Lepidopteran pests such as Heliothis armigera Hübner and Ostrinia furnacalis Guenée. The Bt cry1Ie gene also has no cross resistance with other insecticidal proteins such as Cry1Ab, Cry1Ac, Cry1Ah, or Cry1F. Chinese honey bees (Apis cerana cerana) are potentially exposed to insect-resistant genetically modified (IRGM) crops expressing Cry1Ie toxin via the collection of IRGM crop pollen. In this study, we tested whether Chinese honey bee workers are negatively affected by sugar syrup containing 20, 200, or 20,000 ng/ml Cry1Ie toxin and 48 ng/ml imidacloprid under controlled laboratory conditions. Our results demonstrated that the Cry1Ie toxin does not adversely impact survival and pollen consumption of Chinese honey bees. However, imidacloprid decreases Chinese honey bee survival and the total pollen consumption on the 5th, 6th, and 18th d of exposure. The described bioassay is suitable to assess the effects of GM expressed toxins against honey bee.


Assuntos
Proteínas de Bactérias/toxicidade , Abelhas/efeitos dos fármacos , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Inseticidas/toxicidade , Pólen , Animais , Toxinas de Bacillus thuringiensis , Abelhas/fisiologia , Dieta , Comportamento Alimentar/efeitos dos fármacos , Imidazóis/toxicidade , Longevidade/efeitos dos fármacos , Neonicotinoides , Nitrocompostos/toxicidade
6.
J Econ Entomol ; 109(3): 1028-1033, 2016 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-27122497

RESUMO

The honey bee ( Apis mellifera L.) is a key nontarget insect in environmental risk assessments of insect-resistant genetically modified crops. In controlled laboratory conditions, we evaluated the potential effects of Cry1Ie toxin on survival, pollen consumption, and olfactory learning of young adult honey bees. We exposed worker bees to syrup containing 20, 200, or 20,000 ng/ml Cry1Ie toxin, and also exposed some bees to 48 ng/ml imidacloprid as a positive control for exposure to a sublethal concentration of a toxic product. Results suggested that Cry1Ie toxin carries no risk to survival, pollen consumption, or learning capabilities of young adult honey bees. However, during oral exposure to the imidacloprid treatments, honey bee learning behavior was affected and bees consumed significantly less pollen than the control and Cry1Ie groups.

7.
Sci Rep ; 6: 24664, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27090812

RESUMO

The honey bee has been regarded as a key species in the environmental risk assessment of biotech crops. Here, the potential adverse effects of Cry1Ie toxin on the midgut bacteria of the worker bees (Apis mellifera ligustica) were investigated under laboratory conditions. Newly emerged bees were fed with different concentrations of Cry1Ie toxin syrups (20 ng/mL, 200 ng/mL, and 20 µg/mL), pure sugar syrup, and 48 ppb of imidacloprid syrups, then sampled after 15 and 30 d. We characterized the dominant midgut bacteria and compared the composition and structure of the midgut bacterial community in all samples using the Illumina MiSeq platform targeting the V3-V4 regions of 16S rDNA. No significant differences in the diversity of the midgut bacteria were observed between the five treatments. This work was the first to show the effects of Cry1Ie toxin on honey bees, and our study provided a theoretical basis for the biosafety assessment of transgenic Cry1Ie maize.


Assuntos
Bacillus thuringiensis/metabolismo , Bactérias/classificação , Toxinas Bacterianas/toxicidade , Abelhas/microbiologia , Intestinos/microbiologia , Animais , Bactérias/genética , Biodiversidade , Plantas Geneticamente Modificadas , Polinização , RNA Ribossômico 16S/genética
8.
J Econ Entomol ; 108(4): 1486-94, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26470287

RESUMO

Honey bees are at an unavoidable risk of exposure to neonicotinoid pesticides, which are used worldwide. Compared with the well-studied roles of these pesticides in nontarget site (including midgut, ovary, or salivary glands), little has been reported in the target sites, the brain. In the current study, laboratory-reared adult worker honey bees (Apis mellifera L.) were treated with sublethal doses of imidacloprid. Neuronal apoptosis was detected using the TUNEL technique for DNA labeling. We observed significantly increased apoptotic markers in dose- and time-dependent manners in brains of bees exposed to imidacloprid. Neuronal activated caspase-3 and mRNA levels of caspase-1, as detected by immunofluorescence and real-time quantitative PCR, respectively, were significantly increased, suggesting that sublethal doses of imidacloprid may induce the caspase-dependent apoptotic pathway. Additionally, the overlap of apoptosis and autophagy in neurons was confirmed by transmission electron microscopy. It further suggests that a relationship exists between neurotoxicity and behavioral changes induced by sublethal doses of imidacloprid, and that there is a need to determine reasonable limits for imidacloprid application in the field to protect pollinators.


Assuntos
Apoptose/efeitos dos fármacos , Abelhas/efeitos dos fármacos , Imidazóis/toxicidade , Inseticidas/toxicidade , Nitrocompostos/toxicidade , Animais , Autofagia , Abelhas/fisiologia , Abelhas/ultraestrutura , Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Encéfalo/ultraestrutura , Caspase 1/genética , Caspase 1/metabolismo , Relação Dose-Resposta a Droga , Marcação In Situ das Extremidades Cortadas , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Microscopia Eletrônica de Transmissão , Neonicotinoides , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Neurônios/ultraestrutura , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
9.
Chin Med J (Engl) ; 128(5): 626-31, 2015 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-25698194

RESUMO

BACKGROUND: Diffusion weighted imaging (DWI), with the applying of intravoxel incoherent motion model, has showed promising results in obtaining additional information about microperfusion and tubular flow associated with morphologic changes in chronic kidney diseases. The study aims to evaluate the potential of T2-weighted signal intensity (SI) and DWI with mono- and bi-exponential models to reflect the serial changes on cisplatin (CP) induced rat renal fibrosis models. METHODS: Magnetic resonance exams were performed prior to and 2 nd day, 4 th day, 6 th day, 8 th day, 2 nd week, 3 rd week and 4 th week after CP injection at a 3.0T with an animal coil. Besides T2-weighted images (T2WI), DWI of 13 b values from 0 to 1500 s/mm 2 was acquired. Apparent diffusion coefficient (ADC), fluid fraction f, pure diffusivity D and pseudodiffusivity DFNx01 values were calculated. The regions of interest were placed on cortex (CO), outer stripe of the outer medulla (OM) and inner stripe of the outer medulla (OM), parameters were measured and compared among different time points. Five rats were scarified at each time point for pathological examination. RESULTS: OM revealed remarkable hyperintense and broadened before it became an obscure thread, while CO demonstrated moderate hyperintense and IM didn't show significant change on T2WI. On all three stripes, ADC values decreased firstly then kept increasing since the 4 th day; f values decreased on all stripes; D values had a tendency to increase with fluctuations but the changes didn't achieve statistical significance; DFNx01 values increased at the 2 nd day then tended to be steady thereafter. Pathological findings revealed tubules epitheliums swelling followed by inflammation cells infiltration, interstitial fibrosis was observed since the 2 nd week. CONCLUSIONS: All of T2-weighted SI, ADC, and biexponential models parameters vary during fibrotic process; biexponential model is superior to monoexponential model in separating changes of microperfusion together with tubular flow from pure diffusion.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Fibrose/diagnóstico , Insuficiência Renal Crônica/diagnóstico , Animais , Cisplatino/uso terapêutico , Progressão da Doença , Nefropatias/diagnóstico , Masculino , Modelos Animais , Ratos , Ratos Sprague-Dawley
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