In the paper entitled ‘Tendon cells in vivo form a three dimensional network of cell processes linked by gap junctions’, by C. M. McNeilly and colleagues (J. Anat.189, pp. 593-600), we are sorry that there was a blemish on Figure 1c. The corrected figure

Aim: The study was aimed to develop mucoadhesive buccal tablets using Aster ericoides leaves mucilage. Background : Mucilages are naturally occurring high-molecular-weight polyuronides, which have been extensively studied for their application in different pharmaceutical dosage forms. Objective: The objective of the present research was to establish the mucilage isolated from the leaves of Aster ericoides as an excipient for the formulation of the mucoadhesive buccal tablet. Method: The mucilage was isolated from the leaves of Aster ericoides by maceration, precipitated with acetone and characterized. Tablets were prepared using wet granulation technique and evaluated for various official tests. Results: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Conclusion: The mucilage was found to be non-toxic on A-431 and Vero cell lines. It was insoluble but swellable in cold and hot water. The results indicate that mucilage can form a three-dimensional network. The pH of the mucilage (6.82 ± 0.13) indicated that it might be non-irritant to the buccal cavity. The mucilage was found to be free from microbes. The release of drug was by Fickian diffusion. The in vivo buccal tablet acceptance was 80%. No significant difference between the diastolic blood pressure of standard and Aster tablets treated volunteer group was recorded. Other: However, to prove the potency of the polymer, in vivo bioavailability studies in human volunteers are needed along with chronic toxicity studies in suitable animal models.

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Tough Double-Network Hydrogels as Scaffolds for Tissue Engineering

Technological Advancements in Biomedicine for Healthcare Applications - Advances in Bioinformatics and Biomedical Engineering ◽

10.4018/978-1-4666-2196-1.ch023 ◽

2012 ◽

pp. 213-222

Author(s):

Jing Jing Yang ◽

Jian Fang Liu ◽

Takayuki Kurokawa ◽

Nobuto Kitamura ◽

Kazunori Yasuda ◽

...

Keyword(s):

Tissue Engineering ◽

Three Dimensional ◽

Cartilage Regeneration ◽

Cell Types ◽

Embryoid Bodies ◽

Living Tissue ◽

Double Network ◽

Dimensional Network

Hydrogels are used as scaffolds for tissue engineering in vitro & in vivo because their three-dimensional network structure and viscoelasticity are similar to those of the macromolecular-based extracellular matrix (ECM) in living tissue. Especially, the synthetic hydrogels with controllable and reproducible properties were used as scaffolds to study the behaviors of cells in vitro and implanted test in vivo. In this review, two different structurally designed hydrogels, single-network (SN) hydrogels and double-network (DN) hydrogels, were used as scaffolds. The behavior of two cell types, anchorage-dependent cells and anchorage-independent cells, and the differentiation behaviors of embryoid bodies (EBs) were investigated on these hydrogels. Furthermore, the behavior of chondrocytes on DN hydrogels in vitro and the spontaneous cartilage regeneration induced by DN hydrogels in vivo was examined.

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Elevated expression of pp60c-src alters a selective morphogenetic property of epithelial cells in vitro without a mitogenic effect.

Molecular and Cellular Biology ◽

10.1128/mcb.8.2.632 ◽

1988 ◽

Vol 8 (2) ◽

pp. 632-646 ◽

Cited By ~ 31

Author(s):

S L Warren ◽

L M Handel ◽

W J Nelson

Keyword(s):

Mdck Cells ◽

Three Dimensional ◽

Biological Action ◽

Growth Potential ◽

Differentiated Cells ◽

Natural Function ◽

Elevated Expression ◽

Cell Processes

Madin-Darby canine kidney (MDCK) cells are highly differentiated and have retained the morphogenetic properties necessary to form polarized, multicellular epithelial structures (cysts) in vitro that resemble epithelial tissues in vivo. We introduced the c-src gene into MDCK cells to elevate the level of the plasma membrane-associated cellular tyrosine kinase, pp60c-src, to levels two- to ninefold higher than that expressed in parent MDCK cells. Our results revealed a highly discriminatory biological action of pp60c-src on the morphogenetic properties of MDCK cells. Elevated expression of pp60c-src conferred on MDCK cells the ability to undergo dramatic changes of cell shape that includes the formation of long cell processes (100 to 200 microns), never observed in control MDCK cells. The morphogenesis of multicellular epithelial cysts was altered by elevated levels of pp60c-src and led to predictable distortions of their three-dimensional architecture. However, these cells established morphologically normal cell polarity, formed adhesive epithelial cell-cell contacts indistinguishable from those of control MDCK cells, and exhibited neither focus-forming ability or anchorage-independent growth potential. Finally, we showed that MDCK cells expressing elevated levels of pp60c-src exhibit increased phosphorylation of a more limited number of phosphotyrosine-containing proteins than MDCK cells expressing pp60v-src. We suggest that a natural function of pp60c-src is to regulate the morphogenetic properties which determine the shape of differentiated cells and multicellular structures.

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Keratocyte networks visualised in the living cornea using vital dyes

Journal of Cell Science ◽

10.1242/jcs.106.2.685 ◽

1993 ◽

Vol 106 (2) ◽

pp. 685-691 ◽

Cited By ~ 1

Author(s):

C.A. Poole ◽

N.H. Brookes ◽

G.M. Clover

Keyword(s):

Three Dimensional ◽

Corneal Stroma ◽

Molecular Probes ◽

Dead Cell ◽

High Concentration ◽

Vital Dyes ◽

Dimensional Network ◽

Cell Processes ◽

Connective Tissue Matrix ◽

Tissue Matrix

Fluorescent viability probes have been used to visualise and investigate the viability, morphology and organisation of the keratocyte within the stroma of the intact living cornea. The live cell probe, calcien-AM, in combination with a dead cell probe, ethidium homodimer (Live/Dead Assay, Molecular Probes, U.S.A.) proved superior to earlier generation vital dyes such as fluorescein diacetate or 5,6-carboxyfluorescein diacetate, initially used in combination with ethidium bromide. The ubiquitous distribution of esterase enzymes that cleave calcien-AM within the keratocyte cytoplasm produced a high concentration of fluorescently active calcein throughout the cell, including fine cell processes. Epi-illuminated fluorescence microscopy on transparent corneal dissections subsequently revealed details of keratocyte microanatomy and three-dimensional network organisation in situ. Three morphologically discrete subpopulations of keratocytes were identified: two formed relatively small bands of cells, immediately subjacent to either Bowman's or Descemet's membranes, the third subpopulation constituting the majority of keratocytes typically located within the corneal stroma. The results indicate that calcein-AM is able to penetrate intact living cornea revealing cell viability, and it also has the capacity to ‘trace’ cellular elements and reveal fine structure within a dense connective tissue matrix.

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Evidence for the persistence of a decondensed chromosome scaffold in the interphase nucleus

Journal of Cell Science ◽

10.1242/jcs.86.1.155 ◽

1986 ◽

Vol 86 (1) ◽

pp. 155-171

Author(s):

A.G. Bekers ◽

A.C. Pieck ◽

A.A. Rijken ◽

F. Wanka

Keyword(s):

Three Dimensional ◽

Protein Composition ◽

Bovine Liver ◽

Dimensional Network ◽

Dna Attachment ◽

Cross Bridges ◽

Triton X ◽

Chromosome Scaffold

Nuclei of in vitro cultured bovine liver cells, deprived of the membranes by Triton X-100, were treated with 2 M-NaCl and DNase. Changes in ultrastructure and protein composition were studied at successive steps during treatment. Electron micrographs of nuclei treated with 2 M-NaCl showed a peripheral lamina and an internal system of randomly coiled filaments embedded in a mass of DNA fibres. After partial removal of the DNA the filaments could be seen to serve as backbones for the DNA attachment. Artificial redistribution occurring during fixation with glutaraldehyde suggests that the salt-resistant filaments are not stably cross-bridged into a three-dimensional network. The existence of reversible cross-bridges in vivo cannot be excluded, however. From the available data it is inferred that the filaments represent a decondensed from of the chromosome scaffolds and play a basic role in the organization of the genome throughout the nuclear cycle.

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Synthesis and crystal structures of a 3-acetylated (20S,24S)-ocotillol-type saponin and its C-24 epimer

Acta Crystallographica Section C Structural Chemistry ◽

10.1107/s2053229617006507 ◽

2017 ◽

Vol 73 (6) ◽

pp. 464-469 ◽

Cited By ~ 1

Author(s):

Juan Liu ◽

Yang-Rong Xu ◽

Xing-Si An ◽

Gui-Ge Hou ◽

Qing-Guo Meng

Keyword(s):

Hydrogen Bonds ◽

Three Dimensional ◽

Water Molecules ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Dimensional Network ◽

Crystal Packings ◽

C Nmr

In order to study the in vivo protective effect on myocardial ischemia, (20S,24R)-epoxydammarane-12β,25-diol, (V), and (20S,24S)-epoxydammarane-12β,25-diol, (VI), were synthesized through a novel synthetic route. Two key intermediates, namely (20S,24R)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, (III) [obtained as the hemihydrate, C32H54O5·0.5H2O, (IIIa), and the ethanol hemisolvate, C32H54O5·0.5C2H5OH, (IIIb), with identical conformations but different crystal packings], and (20S,24S)-3-acetyl-20,24-epoxydammarane-3β,12β,25-triol, C32H54O5, (IV), were obtained during the synthesis. The structures were confirmed by 1H NMR, 13C NMR and HRMS analyses, and single-crystal X-ray diffraction. Molecules of (IIIa) are extended into a two-dimensional network constructed with water molecules linked alternately through intermolecular O—H...O hydrogen bonds, which are further stacked into a three-dimensional network. Compound (IIIb) contains two completely asymmetric molecules, which are linked in a disordered manner through intermolecular C—H...O hydrogen bonds. While the crystal stacks in compound (IV) are linked via weak C—H...O hydrogen bonds, the hydrogen-bonded chains extend helically along the crystallographic b axis.

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Subthreshold somatic voltage in neocortical pyramidal cells can control whether spikes propagate from the axonal plexus to axon terminals: a model study

Journal of Neurophysiology ◽

10.1152/jn.00709.2011 ◽

2012 ◽

Vol 107 (10) ◽

pp. 2833-2852 ◽

Cited By ~ 3

Author(s):

Erin Munro ◽

Nancy Kopell

Keyword(s):

Gap Junctions ◽

Pyramidal Cell ◽

Action Potentials ◽

Three Dimensional ◽

Pyramidal Cells ◽

Axon Terminals ◽

Model Study ◽

Rat Somatosensory Cortex ◽

Fast Oscillations

There is suggestive evidence that pyramidal cell axons in neocortex may be coupled by gap junctions into an “axonal plexus” capable of generating very fast oscillations (VFOs) with frequencies exceeding 80 Hz. It is not obvious, however, how a pyramidal cell in such a network could control its output when action potentials are free to propagate from the axons of other pyramidal cells into its own axon. We address this problem by means of simulations based on three-dimensional reconstructions of pyramidal cells from rat somatosensory cortex. We show that somatic depolarization enables propagation via gap junctions into the initial segment and main axon, while somatic hyperpolarization disables it. We show further that somatic voltage cannot effectively control action potential propagation through gap junctions on minor collaterals; action potentials may therefore propagate freely from such collaterals regardless of somatic voltage. In previous work, VFOs are all but abolished during the hyperpolarization phase of slow oscillations induced by anesthesia in vivo. This finding constrains the density of gap junctions on collaterals in our model and suggests that axonal sprouting due to cortical lesions may result in abnormally high gap junction density on collaterals, leading in turn to excessive VFO activity and hence to epilepsy via kindling.

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Poly-Epsilon-Lysine Hydrogels with Dynamic Crosslinking Facilitates Cell Proliferation

Materials ◽

10.3390/ma13173851 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3851

Author(s):

Nestor Lopez Mora ◽

Matthew Owens ◽

Sara Schmidt ◽

Andreia F. Silva ◽

Mark Bradley

Keyword(s):

Biomedical Applications ◽

Cell Attachment ◽

Three Dimensional ◽

Cellular Migration ◽

Cellular Processes ◽

Dimensional Network ◽

Proliferation And Differentiation ◽

Cell Processes ◽

Arginine Glycine Aspartic Acid ◽

Imine Bond

The extracellular matrix (ECM) is a three-dimensional network within which fundamental cell processes such as cell attachment, proliferation, and differentiation occur driven by its inherent biological and structural cues. Hydrogels have been used as biomaterials as they possess many of the ECM characteristics that control cellular processes. However, the permanent crosslinking often found in hydrogels fails to recapitulate the dynamic nature of the natural ECM. This not only hinders natural cellular migration but must also limit cellular expansion and growth. Moreover, there is an increased interest in the use of new biopolymers to create biomimetic materials that can be used for biomedical applications. Here we report on the natural polymer poly-ε-lysine in forming dynamic hydrogels via reversible imine bond formation, with cell attachment promoted by arginine-glycine-aspartic acid (RGD) incorporation. Together, the mechanical properties and cell behavior of the dynamic hydrogels with low poly-ε-lysine quantities indicated good cell viability and high metabolic activity.

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Intestinal release of biofilm-like microcolonies encased in calcium-pectinate beads increases probiotic properties of Lacticaseibacillus paracasei

npj Biofilms and Microbiomes ◽

10.1038/s41522-020-00159-3 ◽

2020 ◽

Vol 6 (1) ◽

Author(s):

Arnaud Heumann ◽

Ali Assifaoui ◽

David Da Silva Barreira ◽

Charles Thomas ◽

Romain Briandet ◽

...

Keyword(s):

Extracellular Polymeric Substances ◽

Three Dimensional ◽

Probiotic Bacteria ◽

Probiotic Properties ◽

Gi Tract ◽

Bacterial Development ◽

Dimensional Network ◽

Calcium Pectinate ◽

Harsh Conditions

Abstract In this study, we show that calcium pectinate beads (CPB) allow the formation of 20 µm spherical microcolonies of the probiotic bacteria Lacticaseibacillus paracasei (formerly designated as Lactobacillus paracasei) ATCC334 with a high cell density, reaching more than 10 log (CFU/g). The bacteria within these microcolonies are well structured and adhere to a three-dimensional network made of calcium-pectinate through the synthesis of extracellular polymeric substances (EPS) and thus display a biofilm-like phenotype, an attractive property for their use as probiotics. During bacterial development in the CPB, a coalescence phenomenon arises between neighboring microcolonies accompanied by their peripheral spatialization within the bead. Moreover, the cells of L. paracasei ATCC334 encased in these pectinate beads exhibit increased resistance to acidic stress (pH 1.5), osmotic stress (4.5 M NaCl), the freeze-drying process and combined stresses, simulating the harsh conditions encountered in the gastrointestinal (GI) tract. In vivo, the oral administration of CPB-formulated L. paracasei ATCC334 in mice demonstrated that biofilm-like microcolonies are successfully released from the CPB matrix in the colonic environment. In addition, these CPB-formulated probiotic bacteria display the ability to reduce the severity of a DSS-induced colitis mouse model, with a decrease in colonic mucosal injuries, less inflammation, and reduced weight loss compared to DSS control mice. To conclude, this work paves the way for a new form of probiotic administration in the form of biofilm-like microcolonies with enhanced functionalities.

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