scholarly journals Monodisperse drops templated by 3D-structured microparticles

2020 ◽  
Vol 6 (45) ◽  
pp. eabb9023
Author(s):  
Chueh-Yu Wu ◽  
Mengxing Ouyang ◽  
Bao Wang ◽  
Joseph de Rutte ◽  
Alexis Joo ◽  
...  
Keyword(s):  
Interfacial Energy ◽  
Single Cells ◽  
Three Dimensional ◽  
Cutting Edge ◽  
Immiscible Fluid ◽  
New Approaches ◽  
Formation Conditions ◽  
Surface Chemistries ◽  
Fluid Phases

The ability to create uniform subnanoliter compartments using microfluidic control has enabled new approaches for analysis of single cells and molecules. However, specialized instruments or expertise has been required, slowing the adoption of these cutting-edge applications. Here, we show that three dimensional–structured microparticles with sculpted surface chemistries template uniformly sized aqueous drops when simply mixed with two immiscible fluid phases. In contrast to traditional emulsions, particle-templated drops of a controlled volume occupy a minimum in the interfacial energy of the system, such that a stable monodisperse state results with simple and reproducible formation conditions. We describe techniques to manufacture microscale drop-carrier particles and show that emulsions created with these particles prevent molecular exchange, concentrating reactions within the drops, laying a foundation for sensitive compartmentalized molecular and cell-based assays with minimal instrumentation.

scholarly journals Monodisperse drops templated by 3D-structured microparticles

2020 ◽  
Author(s):  
Chueh-Yu Wu ◽  
Bao Wang ◽  
Joseph de Rutte ◽  
Mengxing Ouyang ◽  
Alexis Joo ◽  
...  
Keyword(s):  
Interfacial Energy ◽  
Single Cells ◽  
Cutting Edge ◽  
Immiscible Fluid ◽  
New Approaches ◽  
Formation Conditions ◽  
Surface Chemistries ◽  
Fluid Phases

AbstractThe ability to create uniform sub-nanoliter compartments using microfluidic control has enabled new approaches for analysis of single cells and molecules. However, specialized instruments or expertise have been required, slowing the adoption of these cutting-edge applications. Here, we show that 3D-structured microparticles with sculpted surface chemistries template uniformly-sized aqueous drops when simply mixed with two immiscible fluid phases. In contrast to traditional emulsions, particle-templated drops of a controlled volume occupy a minimum in the interfacial energy of the system, such that a stable monodisperse state results with simple and reproducible formation conditions. We describe techniques to manufacture microscale drop-carrier particles and show that emulsions created with these particles prevent molecular exchange, concentrating reactions within the drops, laying a foundation for sensitive compartmentalized assays with minimal instrumentation.

Three-dimensional molecular distribution in single cells analysed using the digital imaging microscope

1989 ◽  
Vol 153 (2) ◽  
pp. 133-149 ◽  
Author(s):  
Fredric S. Fay ◽  
Walter Carrington ◽  
Kevin E. Fogarty
Keyword(s):  
Digital Imaging ◽  
Single Cells ◽  
Three Dimensional ◽  
Molecular Distribution

Phase-Field Simulation of Three-Dimensional Dendritic Growth

2010 ◽  
Vol 97-101 ◽  
pp. 3769-3772 ◽  
Author(s):  
Chang Sheng Zhu ◽  
Jun Wei Wang
Keyword(s):  
Computational Methods ◽  
Phase Field ◽  
Interfacial Energy ◽  
Dendritic Growth ◽  
Field Model ◽  
Three Dimensional ◽  
Phase Field Model ◽  
Computational Time ◽  
Field Simulation ◽  
Undercooled Melt

Based on a thin interface limit 3D phase-field model by coupled the anisotropy of interfacial energy and self-designed AADCR to improve on the computational methods for solving phase-field, 3D dendritic growth in pure undercooled melt is implemented successfully. The simulation authentically recreated the 3D dendritic morphological fromation, and receives the dendritic growth rule being consistent with crystallization mechanism. An example indicates that AADCR can decreased 70% computational time compared with not using algorithms for a 3D domain of size 300×300×300 grids, at the same time, the accelerated algorithms’ computed precision is higher and the redundancy is small, therefore, the accelerated method is really an effective method.

scholarly journals Systematic functional characterization of antisense eRNA of protocadherin α composite enhancer

2021 ◽  
Vol 35 (19-20) ◽  
pp. 1383-1394
Author(s):  
Yuxiao Zhou ◽  
Siyuan Xu ◽  
Mo Zhang ◽  
Qiang Wu
Keyword(s):  
Gene Expression ◽  
Molecular Mechanisms ◽  
Single Cells ◽  
Functional Characterization ◽  
Three Dimensional ◽  
Elongation Factor ◽  
Locked Nucleic Acid ◽  
Loop Formation ◽  
Long Distance ◽  
Enhancer Region

Enhancers generate bidirectional noncoding enhancer RNAs (eRNAs) that may regulate gene expression. At present, the eRNA function remains enigmatic. Here, we report a 5′ capped antisense eRNA PEARL (Pcdh eRNA associated with R-loop formation) that is transcribed from the protocadherin (Pcdh) α HS5-1 enhancer region. Through loss- and gain-of-function experiments with CRISPR/Cas9 DNA fragment editing, CRISPRi, and CRISPRa, as well as locked nucleic acid strategies, in conjunction with ChIRP, MeDIP, DRIP, QHR-4C, and HiChIP experiments, we found that PEARL regulates Pcdhα gene expression by forming local RNA–DNA duplexes (R-loops) in situ within the HS5-1 enhancer region to promote long-distance chromatin interactions between distal enhancers and target promoters. In particular, increased levels of eRNA PEARL via perturbing transcription elongation factor SPT6 lead to strengthened local three-dimensional chromatin organization within the Pcdh superTAD. These findings have important implications regarding molecular mechanisms by which the HS5-1 enhancer regulates stochastic Pcdhα promoter choice in single cells in the brain.

scholarly journals Collective forces of tumor spheroids in three-dimensional biopolymer networks

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Christoph Mark ◽  
Thomas J Grundy ◽  
Pamela L Strissel ◽  
David Böhringer ◽  
Nadine Grummel ◽  
...  
Keyword(s):  
Single Cells ◽  
Three Dimensional ◽  
Traction Force ◽  
Tumor Spheroids ◽  
Scale Invariant ◽  
Tissue Samples ◽  
Force Microscopy ◽  
Surrounding Matrix ◽  
Highly Nonlinear ◽  
Contractile Forces

We describe a method for quantifying the contractile forces that tumor spheroids collectively exert on highly nonlinear three-dimensional collagen networks. While three-dimensional traction force microscopy for single cells in a nonlinear matrix is computationally complex due to the variable cell shape, here we exploit the spherical symmetry of tumor spheroids to derive a scale-invariant relationship between spheroid contractility and the surrounding matrix deformations. This relationship allows us to directly translate the magnitude of matrix deformations to the total contractility of arbitrarily sized spheroids. We show that our method is accurate up to strains of 50% and remains valid even for irregularly shaped tissue samples when considering only the deformations in the far field. Finally, we demonstrate that collective forces of tumor spheroids reflect the contractility of individual cells for up to 1 hr after seeding, while collective forces on longer timescales are guided by mechanical feedback from the extracellular matrix.

Study on Different Graphic Representations in Architectural Heritage

2020 ◽  
pp. 163-205
Author(s):  
José T. Garfella-Rubio ◽  
Jesús Máñez-Pitarch ◽  
Joaquín A. Martínez-Moya ◽  
Jaume Gual-Ortí
Keyword(s):  
Comparative Study ◽  
General Public ◽  
New Technologies ◽  
Three Dimensional ◽  
Cutting Edge ◽  
Architectural Heritage ◽  
Advantages And Disadvantages ◽  
Digital Representations ◽  
Graphic Representations ◽  
3D Scanners

In recent years, cutting-edge methods have emerged to gradually replace or be used with traditional methods to carry out graphic surveys of architectural heritage; modern topographic tools such as 3D scanners and specific software. In addition, the new technologies of additive printing and three-dimensional digital representations has made architectural heritage more accessible to the general public. The main objective of this study was to conduct an analysis of each of the methods, to determine their advantages and disadvantages, as well as to carry out a comparative study of the results obtained with each of them.

scholarly journals Mechanical stimulation of single cells by reversible host-guest interactions in 3D microscaffolds

2020 ◽  
Vol 6 (39) ◽  
pp. eabc2648
Author(s):  
Marc Hippler ◽  
Kai Weißenbruch ◽  
Kai Richler ◽  
Enrico D. Lemma ◽  
Masaki Nakahata ◽  
...  
Keyword(s):  
Single Cells ◽  
Three Dimensional ◽  
Stimuli Responsive ◽  
Traction Forces ◽  
Set Point ◽  
Cellular Processes ◽  
Laser Lithography ◽  
Cross Links ◽  
Tensional Homeostasis ◽  
Myosin Motors

Many essential cellular processes are regulated by mechanical properties of their microenvironment. Here, we introduce stimuli-responsive composite scaffolds fabricated by three-dimensional (3D) laser lithography to simultaneously stretch large numbers of single cells in tailored 3D microenvironments. The key material is a stimuli-responsive photoresist containing cross-links formed by noncovalent, directional interactions between β-cyclodextrin (host) and adamantane (guest). This allows reversible actuation under physiological conditions by application of soluble competitive guests. Cells adhering in these scaffolds build up initial traction forces of ~80 nN. After application of an equibiaxial stretch of up to 25%, cells remodel their actin cytoskeleton, double their traction forces, and equilibrate at a new dynamic set point within 30 min. When the stretch is released, traction forces gradually decrease until the initial set point is retrieved. Pharmacological inhibition or knockout of nonmuscle myosin 2A prevents these adjustments, suggesting that cellular tensional homeostasis strongly depends on functional myosin motors.

scholarly journals Aspiration-assisted bioprinting for precise positioning of biologics

2020 ◽  
Vol 6 (10) ◽  
pp. eaaw5111 ◽  
Author(s):  
Bugra Ayan ◽  
Dong Nyoung Heo ◽  
Zhifeng Zhang ◽  
Madhuri Dey ◽  
Adomas Povilianskas ◽  
...  
Keyword(s):  
Self Assembly ◽  
Physical Mechanism ◽  
Single Cells ◽  
Three Dimensional ◽  
3D Bioprinting ◽  
Precise Control ◽  
3D Space ◽  
Magnitude Range ◽  
Wide Range ◽  
Order Of Magnitude

Three-dimensional (3D) bioprinting is an appealing approach for building tissues; however, bioprinting of mini-tissue blocks (i.e., spheroids) with precise control on their positioning in 3D space has been a major obstacle. Here, we unveil “aspiration-assisted bioprinting (AAB),” which enables picking and bioprinting biologics in 3D through harnessing the power of aspiration forces, and when coupled with microvalve bioprinting, it facilitated different biofabrication schemes including scaffold-based or scaffold-free bioprinting at an unprecedented placement precision, ~11% with respect to the spheroid size. We studied the underlying physical mechanism of AAB to understand interactions between aspirated viscoelastic spheroids and physical governing forces during aspiration and bioprinting. We bioprinted a wide range of biologics with dimensions in an order-of-magnitude range including tissue spheroids (80 to 600 μm), tissue strands (~800 μm), or single cells (electrocytes, ~400 μm), and as applications, we illustrated the patterning of angiogenic sprouting spheroids and self-assembly of osteogenic spheroids.

Sign in / Sign up

Export Citation Format

Share Document