scholarly journals Experimental study of tissue-engineered urethra with collagen / chitosan composite as scaffolds

2020 ◽  
Author(s):  
Zhai Hongfeng ◽  
Qiu Changhong ◽  
Jin Jun ◽  
Shao Xin
Keyword(s):  
New Zealand ◽  
Epithelial Cells ◽  
Cell Activity ◽  
Three Dimensional ◽  
Volume Ratio ◽  
In Vivo Experiments ◽  
High Area ◽  
Chitosan Composite

AbstractIn this article we investigated the preparation of tissue-engineered urethra by using the urethral epithelial subculture cells of male New Zealand young rabbits. We inoculated the epithelial cells of urinary mucosa of male New Zealand young rabbits on collagen, chitosan and collagen chitosan composite as scaffolds to prepare tissue-engineered urethra. The results of inverted phase contrast microscope, HE staining and scanning electron microscope of three kinds of tissue-engineered urethra were compared. What’s more, we reported a new method for quantitative and rapid detection of epithelial cell activity of urinary mucosa in situ by Interactive Laser Cytometer. The collagen chitosan composite was more similar to the extracellular matrix of mammalian. Its three-dimensional porous structure had a high area volume ratio, which was conducive to cell adhesion, growth and metabolism. In vitro, the urethral epithelial cells had been cultured on collagen chitosan composite, and the tissue-engineered urethra was successfully prepared, which laid a solid foundation for further in vivo experiments.

Three-dimensional Growth of Renal Epithelial Cells in Vitro: A Tool in Toxicity Testing

1993 ◽  
Vol 21 (2) ◽  
pp. 191-195 ◽  
Author(s):  
Knut-Jan Andersen ◽  
Erik Ilsø Christensen ◽  
Hogne Vik
Keyword(s):  
Epithelial Cells ◽  
Three Dimensional ◽  
Toxicity Testing ◽  
Renal Tissue ◽  
Epithelial Cell Line ◽  
Multicellular Spheroids ◽  
Renal Epithelial Cell ◽  
Renal Epithelial Cells

The tissue culture of multicellular spheroids from the renal epithelial cell line LLC-PK1 (proximal tubule) is described. This represents a biological system of intermediate complexity between renal tissue in vivo and simple monolayer cultures. The multicellular structures, which show many similarities to kidney tubules in vivo, including a vectorial water transport, should prove useful for studying the potential nephrotoxicity of drugs and chemicals in vitro. In addition, the propagation of renal epithelial cells as multicellular spheroids in serum-free culture may provide information on the release of specific biological parameters, which may be suppressed or masked in serum-supplemented media.

scholarly journals The Challenging Melanoma Landscape: From Early Drug Discovery to Clinical Approval

Cells ◽  
2021 ◽  
Vol 10 (11) ◽  
pp. 3088
Author(s):  
Mariana Matias ◽  
Jacinta O. Pinho ◽  
Maria João Penetra ◽  
Gonçalo Campos ◽  
Catarina Pinto Reis ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Drug Evaluation ◽  
Three Dimensional ◽  
Experimental Models ◽  
In Vivo Studies ◽  
Murine Models ◽  
In Vivo Experiments ◽  
Novel Therapeutic Strategies

Melanoma is recognized as the most dangerous type of skin cancer, with high mortality and resistance to currently used treatments. To overcome the limitations of the available therapeutic options, the discovery and development of new, more effective, and safer therapies is required. In this review, the different research steps involved in the process of antimelanoma drug evaluation and selection are explored, including information regarding in silico, in vitro, and in vivo experiments, as well as clinical trial phases. Details are given about the most used cell lines and assays to perform both two- and three-dimensional in vitro screening of drug candidates towards melanoma. For in vivo studies, murine models are, undoubtedly, the most widely used for assessing the therapeutic potential of new compounds and to study the underlying mechanisms of action. Here, the main melanoma murine models are described as well as other animal species. A section is dedicated to ongoing clinical studies, demonstrating the wide interest and successful efforts devoted to melanoma therapy, in particular at advanced stages of the disease, and a final section includes some considerations regarding approval for marketing by regulatory agencies. Overall, considerable commitment is being directed to the continuous development of optimized experimental models, important for the understanding of melanoma biology and for the evaluation and validation of novel therapeutic strategies.

Comparison of gene expression and activation of transcription factors in organoid-derived monolayer intestinal epithelial cells and organoids

2021 ◽  
Author(s):  
Yu Takahashi ◽  
Yu Inoue ◽  
Keitaro Kuze ◽  
Shintaro Sato ◽  
Makoto Shimizu ◽  
...  
Keyword(s):  
Gene Expression ◽  
Epithelial Cells ◽  
Gene Expression Regulation ◽  
Intestinal Epithelial Cells ◽  
Three Dimensional ◽  
Culture Conditions ◽  
Dependent Manner ◽  
Intestinal Epithelial

Abstract Intestinal organoids better represent in vivo intestinal properties than conventionally used established cell lines in vitro. However, they are maintained in three-dimensional culture conditions that may be accompanied by handling complexities. We characterized the properties of human organoid-derived two-dimensionally cultured intestinal epithelial cells (IECs) compared with those of their parental organoids. We found that the expression of several intestinal markers and functional genes were indistinguishable between monolayer IECs and organoids. We further confirmed that their specific ligands equally activate intestinal ligand-activated transcriptional regulators in a dose-dependent manner. The results suggest that culture conditions do not significantly influence the fundamental properties of monolayer IECs originating from organoids, at least from the perspective of gene expression regulation. This will enable their use as novel biological tools to investigate the physiological functions of the human intestine.

scholarly journals 3D Reconstruction of HvRNASET2 Molecule to Understand Its Antibacterial Role

2020 ◽  
Vol 21 (24) ◽  
pp. 9722
Author(s):  
Nicolò Baranzini ◽  
Laura Pulze ◽  
Marcella Reguzzoni ◽  
Rossella Roncoroni ◽  
Viviana Teresa Orlandi ◽  
...  
Keyword(s):  
Light Transmission ◽  
Three Dimensional ◽  
Lipoteichoic Acid ◽  
Type I ◽  
Phagocytic Cells ◽  
In Vivo Experiments ◽  
Macrophage Phagocytosis ◽  
Bacterial Aggregates

Recent studies performed on the invertebrate model Hirudo verbana (medicinal leech) suggest that the T2 ribonucleic enzyme HvRNASET2 modulates the leech’s innate immune response, promoting microbial agglutination and supporting phagocytic cells recruitment in challenged tissues. Indeed, following injection of both lipoteichoic acid (LTA) and Staphylococcus aureus in the leech body wall, HvRNASET2 is expressed by leech type I granulocytes and induces bacterial aggregation to aid macrophage phagocytosis. Here, we investigate the HvRNASET2 antimicrobial role, in particular assessing the effects on the Gram-negative bacteria Escherichia coli. For this purpose, starting from the three-dimensional molecule reconstruction and in silico analyses, the antibacterial activity was evaluated both in vitro and in vivo. The changes induced in treated bacteria, such as agglutination and alteration in wall integrity, were observed by means of light, transmission and scanning electron microscopy. Moreover, immunogold, AMPs (antimicrobial peptides) and lipopolysaccharide (LPS) binding assays were carried out to evaluate HvRNASET2 interaction with the microbial envelopes and the ensuing ability to affect microbial viability. Finally, in vivo experiments confirmed that HvRNASET2 promotes a more rapid phagocytosis of bacterial aggregates by macrophages, representing a novel molecule for counteracting pathogen infections and developing alternative solutions to improve human health.

scholarly journals VIP17/MAL expression modulates epithelial cyst formation and ciliogenesis

2012 ◽  
Vol 303 (8) ◽  
pp. C862-C871 ◽  
Author(s):  
Vinita Takiar ◽  
Kavita Mistry ◽  
Monica Carmosino ◽  
Nicole Schaeren-Wiemers ◽  
Michael J. Caplan
Keyword(s):  
Epithelial Cells ◽  
Primary Cilium ◽  
Three Dimensional ◽  
3D Culture ◽  
Cyst Formation ◽  
Unknown Etiology ◽  
Development In Vitro ◽  
Renal Cystic Diseases

The polarized organization of epithelial cells is required for vectorial solute transport and may be altered in renal cystic diseases. Vesicle integral protein of 17 kDa (VIP17/MAL) is involved in apical vesicle transport. VIP17/MAL overexpression in vivo results in renal cystogenesis of unknown etiology. Renal cystogenesis can occur as a consequence of defects of the primary cilium. To explore the role of VIP17/MAL in renal cystogenesis and ciliogenesis, we examined the polarization and ciliary morphology of wild-type and VIP17/MAL overexpressing Madin-Darby canine kidney renal epithelial cells grown in two-dimensional (2D) and three-dimensional (3D) cyst culture. VIP17/MAL is apically localized when expressed in cells maintained in 2D and 3D culture. VIP17/MAL overexpressing cells produce more multilumen cysts compared with controls. While the distributions of basolateral markers are not affected, VIP17/MAL expression results in aberrant sorting of the apical marker gp135 to the primary cilium. VIP17/MAL overexpression is also associated with shortened or absent cilia. Immunofluorescence analysis performed on kidney sections from VIP17/MAL transgenic mice also demonstrates fewer and shortened cilia within dilated lumens ( P < 0.01). These studies demonstrate that VIP17/MAL overexpression results in abnormal cilium and cyst development, in vitro and in vivo, suggesting that VIP17/MAL overexpressing mice may develop cysts secondary to a ciliary defect.

Differential addressing of 5-HT1A and 5-HT1B receptors in epithelial cells and neurons

1999 ◽  
Vol 112 (6) ◽  
pp. 967-976
Author(s):  
A. Ghavami ◽  
K.L. Stark ◽  
M. Jareb ◽  
S. Ramboz ◽  
L. Segu ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Neuronal Cultures ◽  
Striatal Neurons ◽  
Primary Neuronal Cultures ◽  
Axon Terminals ◽  
In Vivo Experiments ◽  
In Vitro Systems ◽  
The Central Nervous System

The 5-HT1A and 5-HT1B serotonin receptors are expressed in a variety of neurons in the central nervous system. While the 5-HT1A receptor is found on somas and dendrites, the 5-HT1B receptor has been suggested to be localized predominantly on axon terminals. To study the intracellular addressing of these receptors, we have used in vitro systems including Madin-Darby canine kidney (MDCK II) epithelial cells and primary neuronal cultures. Furthermore, we have extended these studies to examine addressing in vivo in transgenic mice. In epithelial cells, 5-HT1A receptors are found on both apical and basolateral membranes while 5-HT1B receptors are found exclusively in intracellular vesicles. In hippocampal neuronal cultures, 5-HT1A receptors are expressed on somatodendritic membranes but are absent from axons. In contrast, 5-HT1B receptors are found on both dendritic and axonal membranes, including growth cones where they accumulate. Using 5-HT1A and 5-HT1B knockout mice and the binary tTA/tetO system, we generated mice expressing these receptors in striatal neurons. These in vivo experiments demonstrate that, in striatal medium spiny neurons, the 5-HT1A receptor is restricted to the somatodendritic level, while 5-HT1B receptors are shipped exclusively toward axon terminals. Therefore, in all systems we have examined, there is a differential sorting of the 5-HT1A and 5-HT1B receptors. Furthermore, we conclude that our in vivo transgenic system is the only model that reconstitutes proper sorting of these receptors.

scholarly journals Epithelia suspended in collagen gels can lose polarity and express characteristics of migrating mesenchymal cells.

1982 ◽  
Vol 95 (1) ◽  
pp. 333-339 ◽  
Author(s):  
G Greenburg ◽  
E D Hay
Keyword(s):  
Epithelial Cells ◽  
Cell Polarity ◽  
Three Dimensional ◽  
Collagen Gel ◽  
Mesenchymal Cells ◽  
Apical Surface ◽  
Collagen Gels ◽  
Mesenchymal Transformation

This study of epithelial-mesenchymal transformation and epithelial cell polarity in vitro reveals that environmental conditions can have a profound effect on the epithelial phenotype, cell shape, and polarity as expressed by the presence of apical and basal surfaces. A number of different adult and embryonic epithelia were suspended within native collagen gels. Under these conditions, cells elongate, detach from the explants, and migrate as individual cells within the three-dimensional lattice, a previously unknown property of well-differentiated epithelia. Epithelial cells from adult and embryonic anterior lens were studied in detail. Elongated cells derived from the apical surface develop pseudopodia and filopodia characteristic of migratory cells and acquire a morphology and ultrastructure virtually indistinguishable from that of mesenchymal cells in vivo. It is concluded from these experiments that the three-dimensional collagen gel can promote dissociation, migration, and acquisition of secretory organelles by differentiated epithelial cells, and can abolish the apical-basal cell polarity characteristic of the original epithelium.

scholarly journals The interleaved partial active shape model (IPASM) search algorithm – towards 3D ultrasound-based bone surface reconstruction

10.29007/rbgl ◽  
2019 ◽  
Author(s):  
Benjamin Hohlmann ◽  
Klaus Radermacher
Keyword(s):  
Search Algorithm ◽  
Three Dimensional ◽  
3D Ultrasound ◽  
Three Dimensional Model ◽  
In Vivo Experiments ◽  
Distal Surface ◽  
Cheap Alternative ◽  
Orthopedic Applications

Several orthopedic applications require a three-dimensional model of the bone. Ultrasound is a radiation-free and cheap alternative to the state-of-the-art imaging modalities if its limitations in terms of image quality and viewing range can be overcome. This work presents in-vitro as well as in-vivo experiments evaluating the IPASM search, a method for combined segmentation, registration as well as extrapolation. The algorithm is capable to reconstruct the distal surface of a phantom femur with an average surface distance error of roughly 1mm in case of in-vitro as well as below 2mm for in-vivo records, even if the shape varies strongly from the initial model.

Vibration-Assisted Insertion of Flexible Neural Microelectrodes With Bio-Dissolvable Guides for Medical Implantation

2021 ◽  
Author(s):  
Yi Wang ◽  
Yen Yu Ian Shih ◽  
Yuan-shin Lee
Keyword(s):  
Tissue Damage ◽  
Three Dimensional ◽  
Insertion Technique ◽  
Neural Electrode ◽  
In Vivo Experiments ◽  
Neural Probe ◽  
Electrode Insertion ◽  
Neural Microelectrodes

Abstract This paper presents vibration-assisted insertion of flexible neural electrodes with bio-dissolvable guides to deliver accurate microprobe insertion with minimized tissue damage. Invasive flexible neural microprobe is an important new tool for neuromodulation and recording research for medical neurology treatment applications. Flexible neural electrode probes are susceptible to bending and buckling during surgical implantation due to the thin and flexible soft substrates. Inspired by insects in nature, a vibration-assisted insertion technique is developed for flexible neural electrode insertion to deliver accurate microprobe insertion with minimized tissue damage. A three-dimensional combined longitudinal-twisting (L&T) vibration is used to reduce the insertion friction force, and thus reducing soft tissue damage. To reduce the flexible microelectrode buckling during surgical insertion, a bio-dissolvable Polyethylene glycol (PEG) guide is developed for the enhancement of flexible neural probe stiffness. Combining these two methods, the insertion performance of the flexible neural probe is significantly improved. Both the in vitro and the in vivo experiments were conducted to validate the proposed techniques.

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