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•Sonoprinting explains increased nanoparticle delivery after treatment with nanoparticle-loaded microbubbles and ultrasound.•Sonoprinting was investigated in 3D tumor spheroids to ...represent in vivo soft tissue interactions.•Liposomes were delivered to the outer layers of 3D tumor spheroids via sonoprinting.•A complete drug release from the liposomal prints into the deeper layers of the tumor spheroid was seen.•Sonoprinting could enhance the cytotoxicity of both regular and thermosensitive liposomes.
Ultrasound-triggered drug-loaded microbubbles have great potential for drug delivery due to their ability to locally release drugs and simultaneously enhance their delivery into the target tissue. We have recently shown that upon applying ultrasound, nanoparticle-loaded microbubbles can deposit nanoparticles onto cells grown in 2D monolayers, through a process that we termed “sonoprinting”. However, the rigid surfaces on which cell monolayers are typically growing might be a source of acoustic reflections and aspherical microbubble oscillations, which can influence microbubble-cell interactions. In the present study, we aim to reveal whether sonoprinting can also occur in more complex and physiologically relevant tissues, by using free-floating 3D tumor spheroids as a tissue model. We show that both monospheroids (consisting of tumor cells alone) and cospheroids (consisting of tumor cells and fibroblasts, which produce an extracellular matrix) can be sonoprinted. Using doxorubicin-liposome-loaded microbubbles, we show that sonoprinting allows to deposit large amounts of doxorubicin-containing liposomes to the outer cell layers of the spheroids, followed by doxorubicin release into the deeper layers of the spheroids, resulting in a significant reduction in cell viability. Sonoprinting may become an attractive approach to deposit drug patches at the surface of tissues, thereby promoting the delivery of drugs into target tissues.
High-risk Human Papillomaviruses (HPV) has been found to be associated with carcinomas of the cervix, penis, vulva/vagina, anus, mouth and oro-pharynx. As the main tumorigenic effects of the HPV have ...been attributed to the expression of E6 and E7 genes, different gene therapy approaches have been directed to block their expression such as antisense oligonucleotides (ASO), ribozymes and small interfering RNAs. In order to develop a gene-specific therapy for HPV-related cancers, we investigated a potential therapeutic strategy of gene silencing activated under illumination. Our aim according to this antisense therapy consisted in regulating the HPV16 E6 oncogene by using an E6-ASO derivatized with a polyazaaromatic ruthenium (Ru(II)) complex (E6-Ru-ASO) able, under visible illumination, to crosslink irreversibly the targeted sequence. We examined the effects of E6-Ru-ASO on the expression of E6 and on the cell growth of cervical cancer cells. We demonstrated using HPV16(+) SiHa cervical cancer cells that E6-Ru-ASO induces after illumination, a reactivation of p53, the most important target of E6, as well as the inhibition of cell proliferation with a selective repression of E6 at the protein level. These results suggest that E6-Ru ASOs, activated under illumination and specifically targeting E6, are capable of inhibiting HPV16(+) cervical cancer cell proliferation.
We report a medium throughput device to study the effects of combinations of two mechanical stimuli - surface strains and fluid flow shear stresses, on cells. The first generation prototype can ...screen combinations of five strain and five shear stress levels. Computational modeling and empirical measurements were used to determine the generated strains and flows. Uniform equibiaxial strains up to 20% and shear stresses up to 0.3 Pa can be generated. Compatibility of the device with cell culture and end point fixation, staining and imaging is shown using C2C12 mouse myoblast cells.
Extracellular vesicles (EVs) have great potential as biomarkers since their composition and concentration in biofluids are disease state dependent and their cargo can contain disease-related ...information. Large tumor-derived EVs (tdEVs, >1 μm) in blood from cancer patients are associated with poor outcome, and changes in their number can be used to monitor therapy effectiveness. Whereas, small tumor-derived EVs (<1 μm) are likely to outnumber their larger counterparts, thereby offering better statistical significance, identification and quantification of small tdEVs are more challenging. In the blood of cancer patients, a subpopulation of EVs originate from tumor cells, but these EVs are outnumbered by non-EV particles and EVs from other origin. In the Dutch NWO Perspectief Cancer-ID program, we developed and evaluated detection and characterization techniques to distinguish EVs from non-EV particles and other EVs. Despite low signal amplitudes, we identified characteristics of these small tdEVs that may enable the enumeration of small tdEVs and extract relevant information. The insights obtained from Cancer-ID can help to explore the full potential of tdEVs in the clinic.
A novel micromachining process for the fabrication of miniaturised polysilicon-based nanoelectrospray ionisation–mass spectrometry (nanoESI–MS) sources is developed in this paper. The nanoESI source ...topology is composed of two highly planar triangular free-standing cantilevers which form a microfluidic capillary slot having a width (
w
) and a height (
h). A combination of low pressure chemical vapour deposition (LPCVD), pattern-transfer, reactive ion etching (RIE) and sacrificial layer etching is used to fabricate the nanoESI sources which project horizontally beyond the edge of a silicon substrate by a length of 800
μm. NanoESI sources having two different capillary slot dimensions are tested:
w
×
h
=
1.8
μm
×
2
μm and 2.5
μm
×
5
μm. The sources have been tested on an ion trap mass spectrometer (MS) using a standard peptide sample (Glu-Fibrinopeptide B) at a concentration of 1
μM. The resultant mass spectra show that the microfabricated capillary slot-based nanoESI sources presented here demonstrate state-of-the-art performances in terms of electrospray ionisation voltage (0.7
kV) and test solution aqueous concentration (90% H
2O).
Monoliths for microfluidic devices in proteomics Le Gac, Séverine; Carlier, Julien; Camart, Jean-Christophe ...
Journal of chromatography. B,
08/2004, Letnik:
808, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
We report here on the preparation of monolithic capillary columns in view to their integration in a microsystem for on-chip sample preparation before their on-line analysis by electrospray and mass ...spectrometry (ESI–MS). These monolithic columns are based on polymer materials and consist of reverse phases for peptide separation and/or desalting. They were prepared using lauryl methacrylate (LMA), ethylene dimethacrylate (EDMA) as well as a suitable porogenic mixture composed of cyclohexanol and ethylene glycol. The resulting stationary phases present thus a C12-functionality. The LMA-based columns were first prepared in a capillary format using capillary tubing of 75
μm i.d. and tested in nanoLC–MS experiments for the separation of a commercial Cytochrome
C digest composed of 12 peptidic fragments whose isoelectric point values and hydrophobic character cover a wide range. The LMA-based columns were capable of separating the peptidic fragments and their performances were seen to be similar as those of standard commercial columns dedicated to proteomic purposes with calculated separation efficiencies up to 145×10
3 plates/m. Monolithic LMA-based phases were then successfully polymerized in microchannels fabricated using the negative photoresist SU-8. After the polymerization, the systems were seen to withstand the pressures applied during the nanoLC–MS separation tests that were carried out in the same conditions as for the monolithic capillary columns. The pressure drop during these tests of the in-microchannel monoliths was as high as 50
bar; however, the separation was not as good as for a capillary format which could be accounted for by the monolith dimensions.
The catalytic activity of the iron(III) C2 chiral porphyrin Fe(2)(OMe) in alkene cyclopropanation is herein reported. The catalyst promoted the reaction of differently substituted styrenes with diazo ...derivatives with trans‐diastereoselectivities and enantioselectivities up to 99:1 and 87 %, respectively. In addition, high TON and TOF values (up to 10 000 and 120 000 h−1, respectively) were observed indicating good activity and stability of the catalyst in optimized experimental conditions. The study of the cyclopropanation reaction revealed that the porphyrin skeleton is composed of two ‘totem’ parts which were independently responsible for the observed enantio‐ and diastereoselectivities. To further our research we also investigated the catalytic role of the methoxy axial ligand coordinated to the iron atom. The molecular structure of Fe(2)(OMe) was optimized by DFT calculations which were also employed to achieve a better understanding of the mechanistic details of the carbene transfer reaction.
Distinct regions: The activity of an iron(III) C2 chiral bis‐strapped porphyrin catalyst to promote the cyclopropanation of differently substituted styrenes by diazo derivatives is herein reported. Good stereoselectivities (up to 87 % ee and 99:1 d.r.trans) and high TON and TOF values (up to 10 000 and 120 000 h−1, respectively) were achieved. A DFT study was also performed to investigate some mechanistic aspects of the catalytic reaction.
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