The Research on Multi-Material 3D Vascularized Network Integrated Printing Technology

Three-dimensional bioprinting has emerged as one of the manufacturing approaches that could potentially fabricate vascularized channels, which is helpful to culture tissues in vitro. In this paper, we report a novel approach to fabricate 3D perfusable channels by using the combination of extrusion and inkjet techniques in an integrated manufacture process. To achieve this, firstly we investigate the theoretical model to analyze influencing factors of structural dimensions of the printed parts like the printing speed, pressure, dispensing time, and voltage. In the experiment, photocurable hydrogel was printed to form a self-supporting structure with internal channel grooves. When the desired height of hydrogel was reached, the dual print-head was switched to the piezoelectric nozzle immediately, and the sacrificial material was printed by the changed nozzle on the printed hydrogel layer. Then, the extrusion nozzle was switched to print the next hydrogel layer. Once the printing of the internal construct was finished, hydrogel was extruded to wrap the entire structure, and the construct was immersed in a CaCl2 solution to crosslink. After that, the channel was formed by removing the sacrificial material. This approach can potentially provide a strategy for fabricating 3D vascularized channels and advance the development of culturing thick tissues in vitro.

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Osteogenic Properties of 3D-Printed Silica-Carbon-Calcite Composite Scaffolds: Novel Approach for Personalized Bone Tissue Regeneration

International Journal of Molecular Sciences ◽

10.3390/ijms22020475 ◽

2021 ◽

Vol 22 (2) ◽

pp. 475

Author(s):

Parastoo Memarian ◽

Francesco Sartor ◽

Enrico Bernardo ◽

Hamada Elsayed ◽

Batur Ercan ◽

...

Keyword(s):

Osteogenic Differentiation ◽

Bone Tissue ◽

Cell Attachment ◽

Three Dimensional ◽

Bone Tissue Regeneration ◽

Hemolysis Assay ◽

Novel Approach ◽

Related Transcription Factor ◽

Diphenyl Tetrazolium Bromide

Carbon enriched bioceramic (C-Bio) scaffolds have recently shown exceptional results in terms of their biological and mechanical properties. The present study aims at assessing the ability of the C-Bio scaffolds to affect the commitment of canine adipose-derived mesenchymal stem cells (cAD-MSCs) and investigating the influence of carbon on cell proliferation and osteogenic differentiation of cAD-MSCs in vitro. The commitment of cAD-MSCs to an osteoblastic phenotype has been evaluated by expression of several osteogenic markers using real-time PCR. Biocompatibility analyses through 3-(4,5-dimethyl- thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), lactate dehydrogenase (LDH) activity, hemolysis assay, and Ames test demonstrated excellent biocompatibility of both materials. A significant increase in the extracellular alkaline phosphatase (ALP) activity and expression of runt-related transcription factor (RUNX), ALP, osterix (OSX), and receptor activator of nuclear factor kappa-Β ligand (RANKL) genes was observed in C-Bio scaffolds compared to those without carbon (Bio). Scanning electron microscopy (SEM) demonstrated excellent cell attachment on both material surfaces; however, the cellular layer on C-Bio fibers exhibited an apparent secretome activity. Based on our findings, graphene can improve cell adhesion, growth, and osteogenic differentiation of cAD-MSCs in vitro. This study proposed carbon as an additive for a novel three-dimensional (3D)-printable biocompatible scaffold which could become the key structural material for bone tissue reconstruction.

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Mucoadhesive films inside the colonic tube: performance in a three-dimensional world

Journal of The Royal Society Interface ◽

10.1098/rsif.2008.0075 ◽

2008 ◽

Vol 5 (28) ◽

pp. 1353-1362 ◽

Cited By ~ 4

Author(s):

D Dodou ◽

M van den Berg ◽

J van Gennip ◽

P Breedveld ◽

P.A Wieringa

Keyword(s):

Theoretical Model ◽

Contact Area ◽

Material Properties ◽

Three Dimensional ◽

Colonic Tissue ◽

Colonic Wall ◽

Geometric Characteristics ◽

Simple Theoretical Model ◽

Frictional Behaviour

A self-propelling colonoscopic device moving inside the colonic tube should be able to periodically grip safely to the colonic wall as well as to manipulate the generated friction. The feasibility of achieving high grip and friction manipulation by covering the device with mucoadhesive films is experimentally tested. More precisely, the frictional behaviour of mucoadhesive films inside the colonic tube is tested in vitro in porcine colon. It appears that mucoadhesive films generate significantly higher friction than conventional materials (ANOVA p =0, 95% CIs=−3.04, −2.14). The geometry of the film plays a role as well. When holes are, for instance, present in the film geometry and are large enough so that the colonic tissue can wrap their borders, friction can be significantly increased (ANOVA p =0, 95% CIs=−2.53, −1.26). By altering the contact area or the film geometry, friction manipulation can be achieved. Moreover, a simple theoretical model is developed and experimentally verified ( R =0.92). The model can be used to estimate the level of the friction generated by three-dimensional configurations of mucoadhesive films as a function of their geometric characteristics and the material properties of the colon.

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Formulation and Evaluation of Nanosponges loaded Bifonazole for Fun-gal Infection

Anti-Infective Agents ◽

10.2174/2211352518999200711164437 ◽

2020 ◽

Vol 18 ◽

Author(s):

Amaravathi Murali Krishna ◽

Venkatesh Dinnekere Putte Gowda ◽

Roopa Karki

Keyword(s):

Drug Release ◽

Fungal Infections ◽

Skin Irritation ◽

In Vitro Release ◽

Three Dimensional ◽

Entrapment Efficiency ◽

In Vitro Drug Release ◽

Model Stability ◽

Novel Approach

Background: Nanosponges is a novel approach of topical drug delivery, especially for the fungal infections. Nanosponges are a unique class of nanoparticles with three-dimensional nanostructure in nanometers wide cavities, which can encapsulate both hydrophilic and lipophilic substances, will provide increased efficacy and safety. Objective: To formulate and evaluate Bifonazole loaded nanosponges in hydrogels for the treatment of fungal diseases. Methods: Bifonazole-loaded nanosponges to be formulated using emulsion solvent diffusion technique. Interaction of drugethyl cellulose polymer along with other excipients’ was done by using FTIR as well as DSC. The nanosponges formulations were evaluated with different parameters. Results: Bifonazole loaded nanosponges’ particle size and zeta potential for formulations were between the range of 183.7 to 560.2 nm and –17.77 to –21.9 mV, respectively. Surface morphology of nanosponges by SEM disclosed that it was spherical and porous in nature. Drug entrapment efficiency was found to be 45.44 to 79.71%. The drug release study was done by using phosphate buffer pH 6.8. Further in vitro release data is fitted in to kinetic models. The optimized formulation M6 has incorporated hydrogels, further evaluated skin irritation, in vitro drug release, viscosity and pH using a rat model. Stability studies of hydrogel formulation MH2 revealed that no changes in in-vitro drug release, pH and drug content study at the completion of 6 months. Conclusion: Thus, it indicated that the prepared Bifonazole loaded nanosponges into hydrogel was stable. Hence, it could be a suitable dosage form for the cure of fungal infections in the skin.

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Development and Application of an Additively Manufactured Calcium Chloride Nebulizer for Alginate 3D-Bioprinting Purposes

Journal of Functional Biomaterials ◽

10.3390/jfb9040063 ◽

2018 ◽

Vol 9 (4) ◽

pp. 63 ◽

Cited By ~ 9

Author(s):

Lukas Raddatz ◽

Antonina Lavrentieva ◽

Iliyana Pepelanova ◽

Janina Bahnemann ◽

Dominik Geier ◽

...

Keyword(s):

Cell Culture ◽

Culture Media ◽

Single Cells ◽

Matrix Material ◽

Three Dimensional ◽

Culture Cell ◽

3D Bioprinting ◽

Cacl2 Solution

Three-dimensional (3D)-bioprinting enables scientists to mimic in vivo micro-environments and to perform in vitro cell experiments under more physiological conditions than is possible with conventional two-dimensional (2D) cell culture. Cell-laden biomaterials (bioinks) are precisely processed to bioengineer tissue three-dimensionally. One primarily used matrix material is sodium alginate. This natural biopolymer provides both fine mechanical properties when gelated and high biocompatibility. Commonly, alginate is 3D bioprinted using extrusion based devices. The gelation reaction is hereby induced by a CaCl2 solution in the building chamber after material extrusion. This established technique has two main disadvantages: (1) CaCl2 can have toxic effects on the cell-laden hydrogels by oxygen diffusion limitation and (2) good printing resolution in the CaCl2 solution is hard to achieve, since the solution needs to be removed afterwards and substituted by cell culture media. Here, we show an innovative approach of alginate bioprinting based on a CaCl2 nebulizer. The device provides CaCl2 mist to the building platform inducing the gelation. The necessary amount of CaCl2 could be decreased as compared to previous gelation strategies and limitation of oxygen transfer during bioprinting can be reduced. The device was manufactured using the MJP-3D printing technique. Subsequently, its digital blueprint (CAD file) can be modified and additive manufactured easily and mounted in various extrusion bioprinters. With our approach, a concept for a more gentle 3D Bioprinting method could be shown. We demonstrated that the concept of an ultrasound-based nebulizer for CaCl2 mist generation can be used for 3D bioprinting and that the mist-induced polymerization of alginate hydrogels of different concentrations is feasible. Furthermore, different cell-laden alginate concentrations could be used: Cell spheroids (mesenchymal stem cells) and single cells (mouse fibroblasts) were successfully 3D printed yielding viable cells and stable hydrogels after 24 h cultivation. We suggest our work to show a different and novel approach on alginate bioprinting, which could be useful in generating cell-laden hydrogel constructs for e.g., drug screening or (soft) tissue engineering applications.

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Abstract 565: LPA-PKD-1-HDAC7/NCoR1-FoxO1 Signaling Axis Regulates Endothelial Cell CD36 Transcription and Stimulates Arteriogenic Responses

Arteriosclerosis Thrombosis and Vascular Biology ◽

10.1161/atvb.34.suppl_1.565 ◽

2014 ◽

Vol 34 (suppl_1) ◽

Author(s):

Bin Ren ◽

Devi P Ramakrishnan ◽

Brian Walcott ◽

Yiliang Chen ◽

Brad Best ◽

...

Keyword(s):

Endothelial Cells ◽

Endothelial Cell ◽

Malignant Tumors ◽

Three Dimensional ◽

Boyden Chamber ◽

Dependent Manner ◽

Novel Approach ◽

Signaling Axis

Lysophosphatidic acid (LPA), a bioactive signaling phospholipid, down-regulates CD36 expression in microvascular endothelial cells (MVECs) via protein kinase PKD-1 signaling, thereby abolishing endothelial cell responses to its antiangiogenic ligand thrombospondin-1. However, little is known regarding mechanisms by which MVEC-specific CD36 transcription is regulated. We describe that in MVECs LPA represses CD36 transcription by activating a PKD-1 signaling that induces formation of a HDAC7/NCoR1/FoxO1 complex in the nucleus. Promoter analysis first identified FoxO1 as a transcription factor responsible for the CD36 transcription, which was confirmed by a chromatin-immunoprecipitation assay. Using a combination of PKD-1 gene transduction with co-immmunoprecipitation assay, we showed an increased interaction of HDAC7/NCoR1 with FoxO1 in response to LPA. However, HDAC7 and FoxO1 interaction was attenuated with PKD-1 silencing. Furthermore, based on results from an angiogenesis profiling with real time qPCR, doxycycline inducible constitutively active PKD-1 plasmids were transduced into tumor associated endothelial cells using a Lentiviral system to induce the PKD-1 expression. The results showed that turning off CD36 transcription reprograms by PKD-1 signaling was accompanied by an induced expression of ephrin B2 and activation of MAPK/ERK1/2 signaling, which are two critical “molecular signatures” involved in arteriogenesis. Moreover, three dimensional spheroid assay, a modified Boyden Chamber assay and in vivo Matrigel assay revealed that turning off CD36 transcription promoted angiogenesis in vitro and in vivo in a PKD-1-dependent manner. Immunofluorescence microscopy also showed the presence of this signaling pathway in the vasculature of Lewis lung carcinomas grown in cd36 deficient mice. In summary, our data suggest that a LPA-PKD-1-HDAC7/NCoR1-FoxO1 signaling axis is critical for transcriptional regulation of CD36 and mediates silencing of this antiangiogenic switch. This subsequently results in MVEC reprogramming for proangiogenic and arteriogenic responses. Therefore, targeting this signaling cascade could be a novel approach for malignant tumors, cardiovascular ischemia and other thrombotic diseases.

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Three-dimensional growth of breast cancer cells potentiates the anti-tumor effects of unacylated ghrelin and AZP-531

eLife ◽

10.7554/elife.56913 ◽

2020 ◽

Vol 9 ◽

Cited By ~ 1

Author(s):

CheukMan C Au ◽

John B Furness ◽

Kara Britt ◽

Sofya Oshchepkova ◽

Heta Ladumor ◽

...

Keyword(s):

Breast Cancer ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Therapeutic Potential ◽

Three Dimensional ◽

Mapk Signaling ◽

Unacylated Ghrelin ◽

Biologically Relevant ◽

Novel Approach

Breast cancer is the most common type of cancer in women and notwithstanding important therapeutic advances, remains the second leading cause of cancer-related death. Despite extensive research relating to the hormone ghrelin, responsible for the stimulation of growth hormone release and appetite, little is known of the effects of its unacylated form, especially in cancer. The present study aimed to characterize effects of unacylated ghrelin on breast cancer cells, define its mechanism of action, and explore the therapeutic potential of unacylated ghrelin or analog AZP-531. We report potent anti-tumor effects of unacylated ghrelin, dependent on cells being cultured in 3D in a biologically-relevant extracellular matrix. The mechanism of unacylated ghrelin-mediated growth inhibition involves activation of Gαi and suppression of MAPK signaling. AZP-531 also suppresses the growth of breast cancer cells in vitro and in xenografts, and may be a novel approach for the safe and effective treatment of breast cancer.

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Ultrastructural Investigations of the Contractile Filaments of Amoebae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050950 ◽

1974 ◽

Vol 32 ◽

pp. 188-189

Author(s):

P.L. Moore

Keyword(s):

Cytoplasmic Streaming ◽

Three Dimensional ◽

Freeze Fracture ◽

Amoeboid Movement ◽

Different Types ◽

Chemical Conditions ◽

Complete Interpretation

Previous freeze fracture results on the intact giant, amoeba Chaos carolinensis indicated the presence of a fibrillar arrangement of filaments within the cytoplasm. A complete interpretation of the three dimensional ultrastructure of these structures, and their possible role in amoeboid movement was not possible, since comparable results could not be obtained with conventional fixation of intact amoebae. Progress in interpreting the freeze fracture images of amoebae required a more thorough understanding of the different types of filaments present in amoebae, and of the ways in which they could be organized while remaining functional.The recent development of a calcium sensitive, demembranated, amoeboid model of Chaos carolinensis has made it possible to achieve a better understanding of such functional arrangements of amoeboid filaments. In these models the motility of demembranated cytoplasm can be controlled in vitro, and the chemical conditions necessary for contractility, and cytoplasmic streaming can be investigated. It is clear from these studies that “fibrils” exist in amoeboid models, and that they are capable of contracting along their length under conditions similar to those which cause contraction in vertebrate muscles.

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Correlated Studies of Cellular Interactions Using TEM, Freeze Etching, and SEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010005161x ◽

1974 ◽

Vol 32 ◽

pp. 320-321

Author(s):

J. P. Revel

Keyword(s):

Developmental Stages ◽

Three Dimensional ◽

Cell Movement ◽

Cellular Interactions ◽

Serial Sections ◽

Cell Sheets ◽

Freeze Etching ◽

Early Developmental

Movement of individual cells or of cell sheets and complex patterns of folding play a prominent role in the early developmental stages of the embryo. Our understanding of these processes is based on three- dimensional reconstructions laboriously prepared from serial sections, and from autoradiographic and other studies. Many concepts have also evolved from extrapolation of investigations of cell movement carried out in vitro. The scanning electron microscope now allows us to examine some of these events in situ. It is possible to prepare dissections of embryos and even of tissues of adult animals which reveal existing relationships between various structures more readily than used to be possible vithout an SEM.

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In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100083035 ◽

1978 ◽

Vol 36 (2) ◽

pp. 434-435

Author(s):

D. Reis ◽

B. Vian ◽

J. C. Roland

Keyword(s):

Cell Wall ◽

Self Assembly ◽

Plant Cell Wall ◽

Higher Plants ◽

Three Dimensional ◽

Cytochemical Study ◽

Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

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