Self-Contained Three-Dimensional Bioprinter for Applications in Cardiovascular Research

Bioprinting is a technique of creating 3D cell-laden structures by accurately dispensing biomaterial to form complex synthetic tissue. The printed constructs aim to mimic the native tissue by preserving the cell functionality and viability within the printed structure. The 3D bioprinting system presented in this paper aims to facilitate the process of 3D bioprinting through its ability to control the environmental parameters within an enclosed printing chamber. This design of the bioprinter targets to eliminate the need for a laminar flow hood, by regulating the necessary environmental conditions important for cell survival, especially during long duration prints. A syringe-based extrusion (SBE) deposition method comprising multiple nozzles is integrated into the system. This allows for a wider selection of biomaterials that can be used for the formation of the extracellular matrix (ECM). Tissue constructs composed of alginate-gelatin hydrogels were mixed with fibrinogen and human endothelial cells which were then characterized and compared using two methodologies: casted and bioprinted. Furthermore, vasculature was incorporated in the bioprinted constructs using sacrificial printing. Structural and functional characterization of the constructs were performed by assessing rheological, mechanical properties, and analyzing live-dead assay measurements.

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Self-Contained 3D Bioprinter for Cardiovascular and Cancer Research

2019 Design of Medical Devices Conference ◽

10.1115/dmd2019-3302 ◽

2019 ◽

Author(s):

Prabhuti Kharel ◽

Likitha Somasekhar ◽

Kevin Fernando ◽

Kunal Mitra

Keyword(s):

Cancer Research ◽

Structural Integrity ◽

Environmental Parameters ◽

Primary Objective ◽

3D Bioprinting ◽

Deposition Method ◽

Fabrication Technology ◽

Tissue Constructs ◽

Living Tissues ◽

Selection Of

Bioprinting is a 3D fabrication technology used to accurately dispense cell-laden biomaterials for the fabrication of complex 3D functional living tissues. A syringe-based extrusion (SBE) deposition method comprising of multiple nozzles is integrated into the system. This allows for a wider selection of biomaterials that can be used for the formation of the extracellular matrix (ECM). The 3D bioprinting system presented in this paper aims to facilitate the process of 3D bioprinting through its ability to control the environmental parameters within an enclosed printing chamber. The primary objective of this research is to print viable 3D tissue constructs seeded with cells with high structural integrity and high resolution.

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Effect of Surface Topography Parameters on Friction and Wear of Random Rough Surface

Materials ◽

10.3390/ma12172762 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2762 ◽

Cited By ~ 4

Author(s):

Ruimin Shi ◽

Bukang Wang ◽

Zhiwei Yan ◽

Zongyan Wang ◽

Lei Dong

Keyword(s):

Surface Topography ◽

Fluid Dynamic ◽

Dynamic Pressure ◽

Functional Characterization ◽

Three Dimensional ◽

Measuring System ◽

Height Distribution ◽

Worn Surface ◽

The Relationship

In order to explore the relationship between the surface topography parameters and friction properties of a rough contact interface under fluid dynamic pressure lubrication conditions, friction experiments were carried out. The three-dimensional surface topography of specimens was measured and characterized with a profile microscopy measuring system and scanning electron microscope. The friction coefficient showed a trend of decreasing first and then increasing with the increase in some surface topography parameters at lower pressure, such as the surface height arithmetic mean Sa, surface height distribution kurtosis Sku, surface volume average volume Vvv, and surface center area average void volume Vvc, which are the ISO 25178 international standard parameters. The effects of surface topographic parameters on friction were analyzed and the wear mechanism of the worn surface was presented. The wear characteristics of the samples were mainly characterized as strain fatigue, grinding, and scraping. The results provide a theoretical basis for the functional characterization of surface topography.

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Functional characterization of the transmembrane segment VII of the NHE1 isoform of the Na+/H+ exchangerThis paper is one of a selection of papers published in this Special Issue, entitled The Cellular and Molecular Basis of Cardiovascular Dysfunction, Dhalla 70th Birthday Tribute.

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y06-081 ◽

2007 ◽

Vol 85 (3-4) ◽

pp. 319-325 ◽

Cited By ~ 9

Author(s):

Jie Ding ◽

Raymond W.P. Ng ◽

Larry Fliegel

Keyword(s):

Amino Acids ◽

70Th Birthday ◽

Functional Characterization ◽

Integral Membrane Protein ◽

Transmembrane Segment ◽

Transmembrane Segments ◽

Pore Lining ◽

Positively Charged ◽

Selection Of

The Na+/H+ exchanger isoform 1 is an integral membrane protein that regulates intracellular pH. It extrudes 1 intracellular H+ in exchange for 1 extracellular Na+. It has 2 large domains, an N-terminal membrane domain of 12 transmembrane segments and an intracellular C-terminal regulatory domain. We characterized the cysteine accessibility of amino acids of the critical transmembrane segment TM VII. Residues Leu 255, Leu 258, Glu 262, Leu 265, Asn 266, Asp 267, Val 269, Val 272, and Leu 273 were all mutated to cysteine residues in the cysteineless NHE1 isoform. Mutation of amino acids E262, N266, and D267 caused severe defects in activity and targeting of the intact full length protein. The balance of the active mutants were examined for sensitivity to the sulfhydryl reactive reagents, positively charged MTSET ((2- (trimethylammonium)ethyl)methanethiosulfonate) and negatively charged MTSES ((2-sulfonatoethyl)methanethiosulfonate). Leu 255 and Leu 258 were sensitive to MTSET but not to MTSES. The results suggest that these amino acids are pore-lining residues. We present a model of TM VII that shows that residues Leu 255, Leu 258, Glu 262, Asn 266, and Asp 267 lie near the same face of TM VII, lining the ion transduction pore.

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Functional Characterization of Three-Dimensional Cortical Cultures for In Vitro Modeling of Brain Networks

iScience ◽

10.1016/j.isci.2020.101434 ◽

2020 ◽

Vol 23 (8) ◽

pp. 101434

Author(s):

Yu-Ting L. Dingle ◽

Volha Liaudanskaya ◽

Liam T. Finnegan ◽

Kyler C. Berlind ◽

Craig Mizzoni ◽

...

Keyword(s):

Functional Characterization ◽

Brain Networks ◽

Three Dimensional ◽

In Vitro Modeling ◽

Cortical Cultures

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Functional Characterization of 21 Rare Allelic CYP1A2 Variants Identified in a Population of 4773 Japanese Individuals by Assessing Phenacetin O-Deethylation

Journal of Personalized Medicine ◽

10.3390/jpm11080690 ◽

2021 ◽

Vol 11 (8) ◽

pp. 690

Author(s):

Masaki Kumondai ◽

Evelyn Marie Gutiérrez Rico ◽

Eiji Hishinuma ◽

Yuya Nakanishi ◽

Shuki Yamazaki ◽

...

Keyword(s):

Enzymatic Activity ◽

Protein Function ◽

Rare Variants ◽

Functional Characterization ◽

Three Dimensional ◽

Additional Information ◽

Metabolic Reactions ◽

Underlying Mechanisms ◽

Cytochrome Content

Cytochrome P450 1A2 (CYP1A2), which accounts for approximately 13% of the total hepatic cytochrome content, catalyzes the metabolic reactions of approximately 9% of frequently used drugs, including theophylline and olanzapine. Substantial inter-individual differences in enzymatic activity have been observed among patients, which could be caused by genetic polymorphisms. Therefore, we functionally characterized 21 novel CYP1A2 variants identified in 4773 Japanese individuals by determining the kinetic parameters of phenacetin O-deethylation. Our results showed that most of the evaluated variants exhibited decreased or no enzymatic activity, which may be attributed to potential structural alterations. Notably, the Leu98Gln, Gly233Arg, Ser380del Gly454Asp, and Arg457Trp variants did not exhibit quantifiable enzymatic activity. Additionally, three-dimensional (3D) docking analyses were performed to further understand the underlying mechanisms behind variant pharmacokinetics. Our data further suggest that despite mutations occurring on the protein surface, accumulating interactions could result in the impairment of protein function through the destabilization of binding regions and changes in protein folding. Therefore, our findings provide additional information regarding rare CYP1A2 genetic variants and how their underlying effects could clarify discrepancies noted in previous phenotypical studies. This would allow the improvement of personalized therapeutics and highlight the importance of identifying and characterizing rare variants.

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Intracellular Bacterial Symbionts in Corals: Challenges and Future Directions

Microorganisms ◽

10.3390/microorganisms9112209 ◽

2021 ◽

Vol 9 (11) ◽

pp. 2209

Author(s):

Justin Maire ◽

Linda L. Blackall ◽

Madeleine J. H. van Oppen

Keyword(s):

Coral Reefs ◽

Coral Bleaching ◽

Functional Characterization ◽

Three Dimensional ◽

Intracellular Bacteria ◽

Bacterial Symbionts ◽

Primary Producers ◽

Future Directions ◽

Symbiotic Relationships

Corals are the main primary producers of coral reefs and build the three-dimensional reef structure that provides habitat to more than 25% of all marine eukaryotes. They harbor a complex consortium of microorganisms, including bacteria, archaea, fungi, viruses, and protists, which they rely on for their survival. The symbiosis between corals and bacteria is poorly studied, and their symbiotic relationships with intracellular bacteria are only just beginning to be acknowledged. In this review, we emphasize the importance of characterizing intracellular bacteria associated with corals and explore how successful approaches used to study such microorganisms in other systems could be adapted for research on corals. We propose a framework for the description, identification, and functional characterization of coral-associated intracellular bacterial symbionts. Finally, we highlight the possible value of intracellular bacteria in microbiome manipulation and mitigating coral bleaching.

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Dynamic transcriptome and chromatin architecture in granulosa cells during chicken folliculogenesis

Nature Communications ◽

10.1038/s41467-021-27800-9 ◽

2022 ◽

Vol 13 (1) ◽

Author(s):

Diyan Li ◽

Chunyou Ning ◽

Jiaman Zhang ◽

Yujie Wang ◽

Qianzi Tang ◽

...

Keyword(s):

Granulosa Cells ◽

Functional Characterization ◽

Three Dimensional ◽

Range Interaction ◽

Ample Evidence ◽

Chromatin Architecture ◽

Complex Biological Process ◽

Preovulatory Follicles ◽

Long Range Interaction

AbstractFolliculogenesis is a complex biological process involving a central oocyte and its surrounding somatic cells. Three-dimensional chromatin architecture is an important transcription regulator; however, little is known about its dynamics and role in transcriptional regulation of granulosa cells during chicken folliculogenesis. We investigate the transcriptomic dynamics of chicken granulosa cells over ten follicular stages and assess the chromatin architecture dynamics and how it influences gene expression in granulosa cells at three key stages: the prehierarchical small white follicles, the first largest preovulatory follicles, and the postovulatory follicles. Our results demonstrate the consistency between the global reprogramming of chromatin architecture and the transcriptomic divergence during folliculogenesis, providing ample evidence for compartmentalization rearrangement, variable organization of topologically associating domains, and rewiring of the long-range interaction between promoter and enhancers. These results provide key insights into avian reproductive biology and provide a foundational dataset for the future in-depth functional characterization of granulosa cells.

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Conductive Nanomaterials used in Bioinks for 3D Bioprinting

Nano LIFE ◽

10.1142/s1793984421300053 ◽

2021 ◽

Vol 11 (02) ◽

pp. 2130005

Author(s):

Sheba Goklany

Keyword(s):

Three Dimensional ◽

Living Cells ◽

Bioactive Molecules ◽

3D Bioprinting ◽

Biological Degradation ◽

High Reproducibility ◽

Tissue Constructs ◽

Conductive Nanomaterials ◽

Supporting Materials ◽

The Ideal

Biofabrication for tissue engineering and regenerative medicine is a rapidly evolving field that incorporates bioprinting or bioassembly for the development of biologically functional products with structural organization using cells, bioactive molecules, and biomaterials. Bioprinting is a biofabrication technology that utilizes biomaterials, living cells, and supporting materials, called bioink, to generate three-dimensional tissue constructs. Bioprinting offers several advantages over traditional scaffolding and microengineering methods such as precise architecture control, high reproducibility, and versatility. The ideal bioink should possess appropriate structural, mechanical, gelation, rheological, chemical, biological, degradation, and biomimetic properties for the desired application of the final product. Several natural and synthetic bioinks have been developed and this review has focused on conductive nanomaterials that have been used in combination with hydrogel materials for bioink synthesis.

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