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1.
Insects ; 12(11)2021 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-34821792

RESUMO

The proboscis is an important feeding organ for the glossatan moths, mainly adapted to the flower and non-flower visiting habits. The clover cutworm, Scotogramma trifolii Rottemberg, and the spotted clover moth, Protoschinia scutosa (Denis & Schiffermuller), are serious polyphagous pests, attacking numerous vegetables and crops, resulting in huge economic losses. However, the feeding behavior and mechanisms of the adult stage remain unsatisfactorily explored. In this study, the proboscis morphology of S. trifolii and P. scutosa are described in detail using scanning electron microscopy, with the aim of investigating the morphological differences and feeding behavior of these two species. The proboscises of S. trifolii and P. scutosa are similar in morphology and structure and are divided into three zones (Zone 1-3) based on the morphological changes of the dorsal legulae. Three sensillum types are located on the proboscises of both species, sensilla chaetica, sensilla basiconica, and sensilla styloconica. Significant differences were observed in the length of the proboscis and each zone between these two species, as well as in sensilla size and number. Based on the morphology of the proboscis and associated sensilla, S. trifolii and P. scutosa are potential flower visitors, which was also reinforced by the pollen observed at the proboscis tip. These results will strengthen our understanding of the structure of the proboscis related to the feeding behavior of Noctuidae.

2.
J Morphol ; 282(5): 733-745, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33644867

RESUMO

Sensory structures on the antennae and mouthparts of insects are associated with various activities, such as host location, feeding, attracting a mate, and identifying a suitable oviposition site. Athetis lepigone (Möschler) is an important polyphagous Eurasian pest with more than 30 species of host plants. The larvae target bud leaves, prop roots, and tender stems of many agricultural crops, but the feeding habits of the adults remain poorly known. Aiming to understand the feeding behavior of the species, we investigated the fine morphology of its antennae and proboscis using scanning electron microscopy. The antennae of both sexes are filiform, and bear eight types of sensilla: Böhm's bristles, sensilla squamiformia, trichodea, chaetica, basiconica, coeloconica, styloconica, and auricillica. Sensilla trichodea are the most abundant among these sensillum types. The proboscis consists of two elongated, interlocked maxillary galeae that enclose the food canal by dorsal and ventral legulae. The external galeal surface is covered with numerous triangular microtrichia on Zone 1 and abundant blunt microbumps on Zone 2. The surface of the food canal bears closely connected and smooth semicircular ridges, gradually tapering toward the proboscis tip. Three types of sensilla are noticeable on the proboscis: sensilla trichodea, basiconica, and styloconica. We briefly discuss the putative functional significance of the antennal and proboscis sensilla and, based on the specific structural modifications of the proboscis, predict a flower-visiting habit for A. lepigone.


Assuntos
Mariposas , Sensilas , Animais , Antenas de Artrópodes , Feminino , Trato Gastrointestinal , Larva , Masculino , Microscopia Eletrônica de Varredura
3.
Colloids Surf B Biointerfaces ; 178: 412-420, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30903980

RESUMO

As zwitterionic polymers show great promise in drug delivery, hyaluronic acid (HA) was deacetylated and grafted with dodecylamine to prepare a pH-sensitive zwitterionic polymer dHAD used as a carrier for antitumor drugs. The polymer was negatively charged at pH 7.4 and became positive at pH 6.2. In vitro delivery of DOX against MCF-7 cells showed that the blank micelle dHAD had low cytotoxicity and the dHAD-DOX micelles could greatly prohibit the growth of the MCF-7 cells. In addition, the dHAD-DOX micelles had higher cellular uptake, indicating that the micelles were rapidly internalized into the cells via CD44 receptor-mediated endocytosis. The in vivo delivery of DOX to tumor-bearing mice confirmed that the dHAD-DOX micelles greatly inhibited the tumor growth and significantly reduced systemic toxicity of DOX. These results demonstrated that biocompatible pH-responsive zwitterionic dHAD micelles are promising carriers for the delivery of DOX.


Assuntos
Doxorrubicina/química , Ácido Hialurônico/química , Polímeros/química , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Sistemas de Liberação de Medicamentos/métodos , Endocitose/efeitos dos fármacos , Humanos , Concentração de Íons de Hidrogênio , Células MCF-7 , Micelas
4.
Bioorg Med Chem Lett ; 26(16): 4025-9, 2016 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-27426864

RESUMO

In our previous Letter, we have carried out the synthesis of a novel DDCTMA cationic lipid which was formulated with DOPE for gene delivery. Herein, we used folic acid (FA) as targeting ligand and cholesterol (Chol) as helper lipid instead of DOPE for enhancing the stability of the liposomes. These liposomes were characterized by dynamic laser scattering (DLS), transmission electron microscopy (TEM) and agarose gel electrophoresis assays of pDNA binding affinity. The lipoplexes were prepared by using different weight ratios of DDCTMA/Chol (1:1, 2:1, 3:1, 4:1) liposomes and different concentrations of FA (50-200µg/mL) combining with pDNA. The transfection efficiencies of the lipoplexes were evaluated using pGFP-N2 and pGL3 plasmid DNA against NCI-H460 cells in vitro. Among them, the optimum gene transfection efficiency with DDCTMA/Chol (3:1)/FA (100µg/mL) was obtained. The results showed that FA could improve the gene transfection efficiencies of DDCTMA/Chol cationic liposome. Our results also convincingly demonstrated FA (100µg/mL)-coated DDCTMA/Chol (3:1) cationic liposome could serve as a promising candidate for the gene delivery.


Assuntos
Ácido Fólico/química , Lipossomos/metabolismo , Transfecção , Cátions/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Colesterol/química , Difusão Dinâmica da Luz , Genes Reporter , Humanos , Lipossomos/química , Lipossomos/toxicidade , Microscopia Eletrônica de Transmissão , Microscopia de Fluorescência , Plasmídeos/química , Plasmídeos/metabolismo
5.
Ai Zheng ; 24(7): 842-5, 2005 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-16004812

RESUMO

BACKGROUND & OBJECTIVE: The major cause of death in breast cancer patients is distant metastasis. This study was to explore the expression and significance of small breast epithelial mucin (SBEM) mRNA, the specific marker of breast cancer, in peripheral blood of breast cancer patients. METHODS: Expression of SBEM mRNA in peripheral blood samples from 67 breast cancer patients, 16 benign breast disease patients, and 20 healthy volunteers was detected by nested reverse transcription-polymerase chain reaction (nested RT-PCR). RESULTS: SBEM mRNA was not detected in healthy volunteers and benign breast disease patients. Positive rate of SBEM mRNA was 50.7% (34/67) in breast cancer patients. Positive rate of SBEM mRNA was 25.0% (2/8) in stage I patients, 45.8% (11/24) in stage II patients, 43.8% (7/16) in stage III patients, and 73.7% (14/19) in stage IV patients, respectively. Positive rate of SBEM mRNA was significantly higher in stage IV patients than in stages I, II, and III patients (P0.05). The expression of SBEM mRNA in peripheral blood was not correlated with patient's age, primary tumor size, pathologic type, and estrogen or progestin receptor status (P0.05). CONCLUSION: SBEM mRNA is specifically expressed in peripheral blood of breast cancer patients, and may be a marker of micrometastasis of breast cancer.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Mucinas/biossíntese , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Adulto , Idoso , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Feminino , Fibroma/metabolismo , Fibroma/patologia , Humanos , Pessoa de Meia-Idade , Mucinas/genética , Estadiamento de Neoplasias , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Receptores de Estrogênio/sangue , Receptores de Progesterona/sangue
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