Delivery, stabilization, and spatiotemporal activation of cargo molecules in cells with positively charged nanoparticles

2012 ◽  
Vol 48 (93) ◽  
pp. 11461 ◽  
Author(s):  
Shuhei Murayama ◽  
Taihei Nishiyama ◽  
Kaihei Takagi ◽  
Fumi Ishizuka ◽  
Tomofumi Santa ◽  
...  
Keyword(s):  
Charged Nanoparticles ◽  
Positively Charged ◽  
In Cells

scholarly journals Layer-by-Layer 3D Constructs of Fibroblasts in Hydrogel for Examining Transdermal Penetration Capability of Nanoparticles

2016 ◽  
Vol 22 (4) ◽  
pp. 447-453 ◽  
Author(s):  
Xiaochun Hou ◽  
Shiying Liu ◽  
Min Wang ◽  
Christian Wiraja ◽  
Wei Huang ◽  
...  
Keyword(s):  
Transdermal Delivery ◽  
Three Dimensional ◽  
Layer By Layer ◽  
Surface Charges ◽  
Skin Model ◽  
Collagen Hydrogel ◽  
Penetration Ability ◽  
Charged Nanoparticles ◽  
Transdermal Penetration ◽  
Positively Charged

Nanoparticles are emerging transdermal delivery systems. Their size and surface properties determine their efficacy and efficiency to penetrate through the skin layers. This work utilizes three-dimensional (3D) bioprinting technology to generate a simplified artificial skin model to rapidly screen nanoparticles for their transdermal penetration ability. Specifically, this model is built through layer-by-layer alternate printing of blank collagen hydrogel and fibroblasts. Through controlling valve on-time, the spacing between printing lines could be accurately tuned, which could enable modulation of cell infiltration in the future. To confirm the effectiveness of this platform, a 3D construct with one layer of fibroblasts sandwiched between two layers of collagen hydrogel is used to screen silica nanoparticles with different surface charges for their penetration ability, with positively charged nanoparticles demonstrating deeper penetration, consistent with the observation from an existing study involving living skin tissue.

scholarly journals The Ndc80 complex uses a tripartite attachment point to couple microtubule depolymerization to chromosome movement

2011 ◽  
Vol 22 (8) ◽  
pp. 1217-1226 ◽  
Author(s):  
John G. Tooley ◽  
Stephanie A. Miller ◽  
P. Todd Stukenberg
Keyword(s):  
Point Mutations ◽  
Chromosome Movement ◽  
Microtubule Depolymerization ◽  
Attachment Point ◽  
Binding Interface ◽  
Binding Data ◽  
Ndc80 Complex ◽  
Positively Charged ◽  
In Cells

In kinetochores, the Ndc80 complex couples the energy in a depolymerizing microtubule to perform the work of moving chromosomes. The complex directly binds microtubules using an unstructured, positively charged N-terminal tail located on Hec1/Ndc80. Hec1/Ndc80 also contains a calponin homology domain (CHD) that increases its affinity for microtubules in vitro, yet whether it is required in cells and how the tail and CHD work together are critical unanswered questions. Human kinetochores containing Hec1/Ndc80 with point mutations in the CHD fail to align chromosomes or form productive microtubule attachments. Kinetochore architecture and spindle checkpoint protein recruitment are unaffected in these mutants, and the loss of CHD function cannot be rescued by removing Aurora B sites from the tail. The interaction between the Hec1/Ndc80 CHD and a microtubule is facilitated by positively charged amino acids on two separate regions of the CHD, and both are required for kinetochores to make stable attachments to microtubules. Chromosome congression in cells also requires positive charge on the Hec1 tail to facilitate microtubule contact. In vitro binding data suggest that charge on the tail regulates attachment by directly increasing microtubule affinity as well as driving cooperative binding of the CHD. These data argue that in vertebrates there is a tripartite attachment point facilitating the interaction between Hec1/Ndc80 and microtubules. We discuss how such a complex microtubule-binding interface may facilitate the coupling of depolymerization to chromosome movement.

scholarly journals Improvement of stem cell-derived exosome release efficiency by surface modified nanoparticles

2020 ◽  
Author(s):  
Dong Jun Park ◽  
Wan Su Yun ◽  
Woo Cheol Kim ◽  
Jeong-Eun Park ◽  
Su Hoon Lee ◽  
...  
Keyword(s):  
Stem Cells ◽  
Stromal Cells ◽  
Molecular Mechanisms ◽  
Genetic Factors ◽  
Autophagosome Formation ◽  
Quantification Limit ◽  
Charged Nanoparticles ◽  
Surface Modified ◽  
Surface Modified Nanoparticles ◽  
Positively Charged

Abstract Background: Mesenchymal stem cells (MSCs) are pluripotent stromal cells that release extracellular vesicles (EVs). EVs contain various growth factors and antioxidants that can positively affect the surrounding cells. Nanoscale MSC-derived EVs, such as exosomes, have been developed as bio-stable nano-type materials. However, some issues such as low yield and difficulty in quantification limit their use. We hypothesized that enhancing exosome production using nanoparticles would stimulate intracellular molecules. Results: Our aim in this study was to elucidate the molecular mechanisms of exosome generation by comparing the internalization of surface-modified, positively charged nanoparticles and exosome generation from MSCs. We determined that Rab7, which is located in the multiple vesicle body and autolysosomal membrane, was increased upon exosome expression and was associated with autophagosome formation. Conclusions: Nanoparticles may migrate to lysosomes during treatment. Simultaneously, intracellular exosome-forming factors can be stimulated during endosomal maturation. MSC-derived exosomes using nanoparticles may increase exosome yield and enable the discovery of nanoparticle-induced genetic factors.

scholarly journals Improvement of stem cell-derived exosome release efficiency by surface-modified nanoparticles

2020 ◽  
Author(s):  
Dong Jun Park ◽  
Wan Su Yun ◽  
Woo Cheol Kim ◽  
Jeong-Eun Park ◽  
Su Hoon Lee ◽  
...  
Keyword(s):  
Stromal Cells ◽  
Molecular Mechanisms ◽  
Genetic Factors ◽  
Autophagosome Formation ◽  
Related Factors ◽  
Quantification Limit ◽  
Charged Nanoparticles ◽  
Surface Modified ◽  
Surface Modified Nanoparticles ◽  
Positively Charged

Abstract Background: Mesenchymal stem cells (MSCs) are pluripotent stromal cells that release extracellular vesicles (EVs). EVs contain various growth factors and antioxidants that can positively affect the surrounding cells. Nanoscale MSC-derived EVs, such as exosomes, have been developed as bio-stable nano-type materials. However, some issues, such as low yield and difficulty in quantification, limit their use. We hypothesized that enhancing exosome production using nanoparticles would stimulate the release of intracellular molecules. Results: The aim of this study was to elucidate the molecular mechanisms of exosome generation by comparing the internalization of surface-modified, positively charged nanoparticles and exosome generation from MSCs. We determined that Rab7, a late endosome and auto-phagosome marker, was increased upon exosome expression and was associated with autophagosome formation. Conclusions: It was concluded that the nanoparticles we developed were transported to the lysosome by clathrin-mediated endocytosis. additionally, entered nanoparticles stimulated that autophagy related factors to release exosome from the MSC. MSC-derived exosomes using nanoparticles may increase exosome yield and enable the discovery of nanoparticle-induced genetic factors.

Fusion of Plant Protoplasts Induced by a Positively Charged Synthetic Phospholipid

1979 ◽  
Vol 34 (5-6) ◽  
pp. 460-462 ◽  
Author(s):  
Toshiyuki Nagata ◽  
Hansjörg Eibl ◽  
Georg Melchers
Keyword(s):  
Cell Fusion ◽  
Chemical Structure ◽  
Positive Charge ◽  
Fusion Activity ◽  
Plant Protoplasts ◽  
Positively Charged ◽  
In Cells

Abstract A newly synthesized phospholipid, 1,2-O-Dipentadecylmethylidene-glycerol-3-phosphoryl-(N-ethyl-amino) -ethanolamine, having positive charge was found to exercise fusion activity on plant proto­ plasts. This phospholipid is not found in cells and has an unusal chemical structure with a dioxolane ring. Some properties of this compound are discussed in relation to phospholipid-induced cell fusion.

Positively Charged Magnetic Nanoparticles for Capture of Circulating Tumor Cells from Clinical Blood Samples

Nano LIFE ◽  
2020 ◽  
Vol 10 (03) ◽  
pp. 1971001 ◽  
Author(s):  
Shengming Wu ◽  
Yilong Wang ◽  
Donglu Shi
Keyword(s):  
Magnetic Nanoparticles ◽  
Cancer Cells ◽  
Cancer Patients ◽  
Tumor Cells ◽  
Circulating Tumor Cells ◽  
Cancer Cell ◽  
Detection Sensitivity ◽  
Blood Samples ◽  
Charged Nanoparticles ◽  
Positively Charged

Isolation of circulating tumor cells (CTCs) from cancer patients is of high value for disease monitoring and metastasis diagnosis. Although many new detection methods have emerged in recent years, the detection of CTCs is a current challenge due to lack of specific and sensitive markers. In our previous work, cancer cell surfaces, from over 20 cancer cell lines, have been shown to be negatively-charged regardless of their phenotype by using electrically-charged nanoparticles as a probe. The strong electrostatic interaction between the negative cancer cells and positively charged nanoparticles can well remain in a physiological liquid environment in the presence of serum proteins, enabling effective binding between them. As a result, the cancer cells can be magnetically separated by employing an external magnet. In this technical report, we present preliminary results on the investigation of CTC isolation from both mimetic and clinical blood samples. We show high CTC detection sensitivity by the positively-charged magnetic nanoparticles (PMNs) even at the original concentration of 10 cells per mL mimetic blood sample. The CTCs in the peripheral blood of colorectal cancer patients were isolated and identified by cellular morphology and immunofluorescence staining.

Directional rolling of positively charged nanoparticles along a flexibility gradient on long DNA molecules

Soft Matter ◽  
2018 ◽  
Vol 14 (5) ◽  
pp. 817-825 ◽  
Author(s):  
Suehyun Park ◽  
Heesun Joo ◽  
Jun Soo Kim
Keyword(s):  
Dna Molecules ◽  
Dna Flexibility ◽  
Charged Nanoparticles ◽  
Positively Charged

Directed rolling of a nanoparticle along a gradient of local DNA flexibility.

Anodic Electrophoretic Deposition of TiO2 Nanoparticles Synthesized Using Sol Gel Method

2013 ◽  
Vol 832 ◽  
pp. 633-638
Author(s):  
Khatijah Aisha Yaacob ◽  
David Jason Riley
Keyword(s):  
Electrophoretic Deposition ◽  
Deposition Time ◽  
Anatase Phase ◽  
Sol Gel ◽  
Particle Diameter ◽  
Deposition Process ◽  
Titanium Isopropoxide ◽  
Solid Loading ◽  
Charged Nanoparticles ◽  
Positively Charged

Many researches on electrophoretic deposition of TiO2 nanoparticles (NPs) use commercial TiO2 nanoparticles from Degussa. TiO2 from Degussa is not use in this research because in order to make the TiO2 nanoparticle electronically charged and move under an applied constant voltage, a small amount of iodine and acetylacetone needs to be added to the suspension. It is suggested that the H+ ions generated by the reaction is absorbed on the suspended particles making them positively charged. For anodic EPD, negatively charged nanoparticles are required. In this research TiO2 nanoparticles were prepared by adding 1 ml of titanium isopropoxide dilute with 1 ml ethanol to 10 ml DI water and stirrer under 0°C for 4 hr. As prepared TiO2 nanoparticle were centrifuged at 5500 rpm for 10 min to isolate the particles from the solution. Then the TiO2 nanoparticles were resuspended in ethanol or water. TiO2 nanoparticle with particle diameter of 4.66 nm and anatase phase were produced. Important electrophoretic deposition process parameters, such as apparent pH of the TiO2 NPs, applied voltage, deposition time and solid loading, were studied during electrophoretic deposition of TiO2 nanoparticles.

Sign in / Sign up

Export Citation Format

Share Document