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1.
Int J Mol Sci ; 25(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891867

RESUMO

MicroRNAs (miRNA) play a vital role in insects' growth and development and have significant potential value in pest control. Previously, we identified miR-306 from small RNA libraries within the English grain aphid, Sitobion avenae, a devasting insect pest for wheat. miR-306 not only involves in wing morphogenesis, but also is critically important for aphid survival. Its specific impacts on the life history traits, however, remain unclear. Here, we evaluate the impact of miR-306 perturbation on S. avenae populations using a two-sex life table approach. This comprehensive analysis revealed that miR-306 perturbation significantly prolongs the developmental stages (9.64% and 8.20%) and adult longevity of S. avenae, while decreasing pre-adult survival rate (41.45% and 38.74%) and slightly reducing average fecundity (5.80% and 13.05%). Overall, miR-306 perturbation negatively affects the life table parameters of the aphid population. The population prediction models show a significant decline in the aphid population 60 days post interference, compared to the control groups (98.14% and 97.76%). Our findings highlight the detrimental effects of miR-306 perturbation on S. avenae population growth and suggest potential candidate genes for the development of RNAi-based biopesticides targeted specifically at this pest species.


Assuntos
Afídeos , MicroRNAs , Animais , Afídeos/genética , Afídeos/fisiologia , MicroRNAs/genética , Longevidade/genética , Fertilidade/genética , Masculino , Feminino
2.
Insects ; 15(6)2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38921173

RESUMO

The investigation of genetics-based biopesticides has become a central focus in pesticide studies due to their inherent advantages, including species specificity, environmental safety, and a wide range of target genes. In this study, a mixture of miR-184 agomir and nanomaterial star polycation (SPc) was used to treat the nymphs of the English grain aphid, Sitobion avenae (F.). The life parameters of the aphids at various developmental stages were analyzed using an age-stage two-sex life table to assess the effect of miR-184 agomir on the experimental population. The results indicated that miR-184 agomir had a significant negative effect on four key life parameters, including the intrinsic rate of increase, the finite rate of increase, the net rate of increase, and the mean generation time. The population prediction revealed a substantial reduction (91.81% and 95.88%) in the population size of S. avenae at 60 d after treatment with miR-184 agomir, compared to the control groups. Our findings suggest that the miR-184 agomir has the potential to reduce the survival rate and mean longevity of S. avenae, highlighting its potential as a promising candidate for the development of an effective genetics-based biopesticide.

3.
Small ; : e2307306, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38312110

RESUMO

Intrinsically magnetic cells naturally occur within organisms and are believed to be linked to iron metabolism and certain cellular functions while the functional significance of this magnetism is largely unexplored. To better understand this property, an approach named Optical Tracking-based Magnetic Sensor (OTMS) has been developed. This multi-target tracking system is designed to measure the magnetic moment of individual cells. The OTMS generates a tunable magnetic field and induces movement in magnetic cells that are subsequently analyzed through a learning-based tracking-by-detection system. The magnetic moment of numerous cells can be calculated simultaneously, thereby providing a quantitative tool to assess cellular magnetic properties within populations. Upon deploying the OTMS, a stable population of magnetic cells in human peripheral monocytes is discovered. Further application in the analysis of clinical blood samples reveals an intriguing pattern: the proportion of magnetic monocytes differs significantly between systemic lupus erythematosus (SLE) patients and healthy volunteers. This variation is positively correlated with disease activity, a trend not observed in patients with rheumatoid arthritis (RA). The study, therefore, presents a new frontier in the investigation of the magnetic characteristics of naturally occurring magnetic cells, opening the door to potential diagnostic and therapeutic applications that leverage cellular magnetism.

4.
Adv Healthc Mater ; 12(32): e2301232, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37709487

RESUMO

Therapeutic cancer vaccines offer the greatest advantage of enhancing antigen-specific immunity against tumors, particularly for immunogenic tumors, such as melanoma. However, clinical responses remain unsatisfactory, primarily due to inadequate T cell priming and the development of acquired immune tolerance. A major obstacle lies in the inefficient uptake of antigen by peripheral dendritic cells (DCs) and their migration to lymph nodes for antigen presentation. In this context, the magnetic delivery of antigen-loaded magnetic liposomes (Ag-MLs) to actively target lymph node, is proposed. These magnetic responsive liposomes contain soluble mouse melanoma lysate and iron oxide nanoparticles in the core, along with the immunostimulatory adjuvant CpG-1826 incorporated into the lipid bilayer. When applied through magnetic targeting in the mouse melanoma model, Ag-MLs accumulate significantly in the target lymph nodes. This accumulation results in increased population of active DCs in lymph nodes and cytotoxic T lymphocytes (CTLs) within tumors, correlating with effective tumor growth inhibition. Overall, this study demonstrates the potential of magnetic targeting as an effective strategy for delivering cancer vaccines and activating the immune response, offering a novel platform for cancer immunotherapies.


Assuntos
Vacinas Anticâncer , Melanoma , Camundongos , Animais , Lipossomos/farmacologia , Células Dendríticas , Vacinas Anticâncer/farmacologia , Melanoma/patologia , Linfonodos/patologia , Fenômenos Magnéticos , Camundongos Endogâmicos C57BL
5.
ACS Sens ; 7(2): 622-631, 2022 02 25.
Artigo em Inglês | MEDLINE | ID: mdl-35157439

RESUMO

On the basis of an abundance of elemental plasmonic nanocrystals identifiable by their unique morphology and intrinsic optoelectronic properties, it is necessary to rationally tailor the structural parameters to optimize the functionalities of nanoassemblies for application as plasmonic circuits/devices. Among them, the plasmonic superlattice membrane has emerged as a novel optically active metamaterial, which is constructed by nanocrystals at a two-dimensional (2D) plane with a highly ordered structure and strong plasmonic coupling interactions. Here, we report on the fabrication of a novel plasmonic superlattice membrane using bimetallic core-shell nano-sea urchins (Nano-SEUs) as meta-atoms. Under the guidance of soft-ligand balancing in conjugation with drying-mediated self-assembly at the air/water interface, well-defined giant 2D superlattices with total lateral dimensions of up to 5 mm wide and 80 nm thick have been synthesized, corresponding to an aspect ratio of 62 500. Programmable morphology control over the Nano-SEUs has been achieved in high yield by rationally tuning the spiky branches as well as the thickness of the silver shell, allowing systematic variation of the plasmonic properties of the membrane. Such superlattice membranes exhibited a strong and reproducible surface-enhanced Raman spectroscopy (SERS) signal that originates from interparticle coupling and electric (E)-field enhancement, enabling an enhancement factor of up to 106. We also demonstrated that the fabricated membrane allows the label-free SERS detection of dopamine from 0.1 nM to 1 µM. Thus, this giant Nano-SEU assembled superlattice membrane can be used as a SERS substrate for on-spot biomarker detection, which paves a robust and inexpensive avenue for highly sensitive and reliable biomedical sensing and diagnostics.


Assuntos
Nanopartículas Metálicas , Análise Espectral Raman , Ouro/química , Nanopartículas Metálicas/química , Prata , Análise Espectral Raman/métodos , Água
6.
Soft Robot ; 9(2): 233-249, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34107748

RESUMO

Robotic grasping has become increasingly important in many application areas such as industrial manufacturing and logistics. Because of the diversity and uncertainty of objects and environments, common grippers with one single grasping mode face difficulties to fulfill all the tasks. Hence, we proposed a soft gripper with multiple grasping modes in this study. The gripper consists of four modular soft fingers integrated with layer jamming structure and tendon-driven mechanism. Each finger's rotating shaft of the base uses a torsional spring to decouple the bending deformation and relative rotation. An octopus-mimicking vacuum sucker is installed in the fingertip to generate suction. The effectiveness of the bending deformation and variable stiffness of the design were proved by finite element simulation. Thus, the control model of the finger was built, and the control strategy of multimode grasping of the gripper was proposed. Three control modes were designed to realize the four anthropomorphic grasping modes, including wrap, pinch, hook, and suck. Furthermore, the grasping performance was evaluated to show the abilities. The experiments indicated the superior performance of the proposed gripper and the multimode grasping ability that satisfies various grasping tasks.


Assuntos
Força da Mão , Robótica , Desenho de Equipamento , Dedos , Tendões
7.
Molecules ; 26(23)2021 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-34885984

RESUMO

Three different LED spectra (W: White light; WFR: W + far-red light; WB: W + blue light) with similar photosynthetic photon flux density (PPFD) were designed to explore the effects of supplementary far-red and blue lights on leaf color, biomass and phytochemicals of two cultivars of red-leaf lettuce ("Yanzhi" and "Red Butter") in an artificial lighting plant factory. Lettuce plants under WB had redder leaf color and significantly higher contents of pigments, such as chlorophyll a, chlorophyll b, chlorophyll (a + b) and anthocyanins. The accumulation of health-promoting compounds, such as vitamin C, vitamin A, total phenolic compounds, total flavonoids and anthocyanins in the two lettuce cultivars were obviously enhanced by WB. Lettuce under WFR showed remarkable increase in fresh weight and dry weight; meanwhile, significant decreases of pigments, total phenolic compounds, total flavonoids and vitamin C were found. Thus, in the plant factory system, the application of WB can improve the coloration and quality of red leaf lettuce while WFR was encouraged for the purpose of elevating the yield of lettuce.


Assuntos
Biomassa , Lactuca/classificação , Lactuca/metabolismo , Iluminação , Compostos Fitoquímicos/análise , Pigmentos Biológicos/análise , Antocianinas/análise , Antocianinas/biossíntese , Ácido Ascórbico/análise , Ácido Ascórbico/biossíntese , Clorofila/análise , Clorofila A/análise , Flavonoides/análise , Flavonoides/biossíntese , Lactuca/química , Fenóis/análise , Fotossíntese , Compostos Fitoquímicos/biossíntese , Vitamina A/análise , Vitamina A/biossíntese
8.
Artigo em Inglês | MEDLINE | ID: mdl-32893493

RESUMO

Iron plays vital roles in many life activities and it is strictly controlled via elaborate metabolic system. Growing evidence has suggested that the dysfunctional iron homeostasis is implicated to many refractory diseases including cancers and neurodegenerations. Systemic and cellular iron are regulated through different pathways but are meanwhile interconnecting with each other via a few key regulators, whose abnormal expressions are often found to be the root causes of many iron disorders. Nano-sensing techniques have enabled the detection and monitoring of such central players, which provide rich information for the iron homeostasis profile through multiplexing and flexible designs. In addition to general sensing, nanoprobes are capable of target imaging and precise local access, which are particularly beneficial for revealing the conditions of intra-/extracellular environments. Nanomaterials have also been applied in some therapies, targeting the aberrant iron metabolism. Various iron uptake pathways have been utilized for target drug delivery and iron level manipulation, while abnormal iron content is notably useful in tumor killing. With brief introduction to the significance of iron homeostasis, this review includes recent works regarding the nanotechnology that has been applied in iron-related diagnostic and therapeutic applications. This article is categorized under: Diagnostic Tools > Biosensing Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease Diagnostic Tools > in vivo Nanodiagnostics and Imaging.


Assuntos
Homeostase , Ferro , Nanomedicina , Nanoestruturas , Humanos
9.
J Magn Reson Imaging ; 34(2): 395-402, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21780231

RESUMO

PURPOSE: To investigate the targeting activity of the peptide (named P1c) derived from connective tissue growth factor (CTGF) to αvß3-rich tumor cells. MATERIALS AND METHODS: P1c was synthesized and conjugated with ultrasuperparamagnetic iron oxide particles (USPIOs) coated with meso-2,3-dimercaptosuccinic acid (DMSA). The specific binding activity of P1c-USPIOs to αvß3 was verified by solid phase binding assay. The combination of P1c-USPIOs with a human primary liver cancer cell (Bel 7402) with αvß3-positive expression and uptake of P1c-USPIOs by cells was investigated by Prussian blue staining, transmission electron microscopy (TEM), and magnetic resonance imaging (MRI). The targeting activity of the probe in vivo was also evaluated using a small-animal tumor model by MRI. RESULTS: The cell uptake of P1c-USPIOs was observed in a dose-dependent manner, whereas no significant particle uptake was found in the plain USPIOs group. The differences on T2*-weighted imaging were also found by MRI and the signal intensity (SI) was statistically reduced after coculture of Bel 7402 cells with P1c-USPIOs at a concentration of 20-80 µg/mL compared with plain USPIOs (P < 0.05). The in vivo study showed that the signal reduction was distributed mainly in the periphery and some central areas of the tumor. The tumor-to-muscle CNR (contrast-to-noise ratio) at 12 hours after the administration of the P1c-USPIOs was statistically significantly different compared to those at 0 hour, 1 hour, or the plain USPIO group (P < 0.05). CONCLUSION: The peptide P1c might be a good candidate as a targeting carrier for drugs or tracers.


Assuntos
Integrina alfaVbeta3/metabolismo , Imageamento por Ressonância Magnética/métodos , Peptídeos/química , Linhagem Celular Tumoral , Corantes/farmacologia , Progressão da Doença , Compostos Férricos/química , Ferrocianetos/farmacologia , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Microscopia Eletrônica de Transmissão/métodos , Metástase Neoplásica , Succímero/farmacologia
10.
Respirology ; 16(3): 500-7, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21265950

RESUMO

BACKGROUND AND OBJECTIVE: Connective tissue growth factor (CTGF) has been identified as playing critical roles in fibrosis and is a promising therapeutic target. In a previous study, we used a phage display library to develop a humanized single-chain variable fragment antibody (scFv) against CTGF. In the present study, the protective effect of anti-CTGF scFv against bleomycin (BL)-induced pulmonary fibrosis was investigated in mice. METHODS: The expression of α-smooth muscle actin in human embryonic lung fibroblast (HELF) cells was analysed by western blotting. A mouse model of pulmonary fibrosis was established by tracheal injection of BL (5 mg/kg). Mice received anti-CTGF scFv (4 mg/kg, three times a week) by i.v. injection. The effects of anti-CTGF scFv were evaluated by leukocyte counts in BAL fluid, hydroxyproline measurements in lung tissue and pathological examination. RESULTS: α-Smooth muscle actin expression was decreased in HELF cells treated with anti-CTGF scFv. Anti-CTGF scFv significantly reduced the numbers of inflammatory leukocytes (total and differential count) in BAL fluid, as well as the hydroxyproline content of lung tissue. The severity of alveolitis and fibrosis in the mouse model was markedly attenuated by treatment with anti-CTGF scFv. CONCLUSIONS: Anti-CTGF scFv may potentially be developed as a useful inhibitor of pulmonary fibrosis.


Assuntos
Fator de Crescimento do Tecido Conjuntivo/imunologia , Fibrose Pulmonar/terapia , Anticorpos de Cadeia Única/uso terapêutico , Actinas/metabolismo , Animais , Bleomicina/efeitos adversos , Bleomicina/toxicidade , Líquido da Lavagem Broncoalveolar/imunologia , Hidroxiprolina/metabolismo , Contagem de Leucócitos , Masculino , Camundongos , Fibrose Pulmonar/induzido quimicamente , Índice de Gravidade de Doença
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