scholarly journals Functional Duality of Chondrocyte Hypertrophy and Biomedical Application Trends in Osteoarthritis

Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1139
Author(s):  
Sunghyun Park ◽  
Alvin Bello ◽  
Yoshie Arai ◽  
Jinsung Ahn ◽  
Dohyun Kim ◽  
...  
Keyword(s):  
Endochondral Ossification ◽  
Biomedical Application ◽  
Physiological State ◽  
Three Dimensional ◽  
Intermediate Stage ◽  
Cartilage Tissue ◽  
Chondrocyte Hypertrophy ◽  
Osteogenic Cells ◽  
Protease Activation ◽  
Key Indicators

Chondrocyte hypertrophy is one of the key indicators in the progression of osteoarthritis (OA). However, compared with other OA indications, such as cartilage collapse, sclerosis, inflammation, and protease activation, the mechanisms by which chondrocyte hypertrophy contributes to OA remain elusive. As the pathological processes in the OA cartilage microenvironment, such as the alterations in the extracellular matrix, are initiated and dictated by the physiological state of the chondrocytes, in-depth knowledge of chondrocyte hypertrophy is necessary to enhance our understanding of the disease pathology and develop therapeutic agents. Chondrocyte hypertrophy is a factor that induces OA progression; it is also a crucial factor in the endochondral ossification. This review elaborates on this dual functionality of chondrocyte hypertrophy in OA progression and endochondral ossification through a description of the characteristics of various genes and signaling, their mechanism, and their distinguishable physiological effects. Chondrocyte hypertrophy in OA progression leads to a decrease in chondrogenic genes and destruction of cartilage tissue. However, in endochondral ossification, it represents an intermediate stage at the process of differentiation of chondrocytes into osteogenic cells. In addition, this review describes the current therapeutic strategies and their mechanisms, involving genes, proteins, cytokines, small molecules, three-dimensional environments, or exosomes, against the OA induced by chondrocyte hypertrophy. Finally, this review proposes that the contrasting roles of chondrocyte hypertrophy are essential for both OA progression and endochondral ossification, and that this cellular process may be targeted to develop OA therapeutics.

Conformational characterization of nucleosome structure by Electron Microscopy

1993 ◽  
Vol 51 ◽  
pp. 194-195
Author(s):  
Gregory J. Czarnota
Keyword(s):  
Electron Microscopy ◽  
Structural Changes ◽  
Physiological State ◽  
Gene Activation ◽  
Three Dimensional ◽  
Macromolecular Complex ◽  
Ultrastructural Studies ◽  
Ionic Environment ◽  
Nucleosome Structure ◽  
Dimensional Reconstruction

Chromatin structure at the fundamental level of the nucleosome is important in vital cellular processes. Recent biochemical and genetic analyses show that nucleosome structure and structural changes are very active participants in gene expression, facilitating or inhibiting transcription and reflecting the physiological state of the cell. Structural states and transitions for this macromolecular complex, composed of DNA wound about a heterotypic octamer of variously modified histone proteins, have been measured by physico-chemical techniques and by enzyme-accessibility and are recognized to occur with various post-translational modifications, gene activation, transformation and with ionic-environment. In spite of studies which indicate various forms of nucleosome structure, all current x-ray and neutron diffraction studies have consistently resulted in only one structure, suggestive of a static conformation. In contrast, two-dimensional electron microscopy studies and three-dimensional reconstruction techniques have yielded different structures. These fundamental differences between EM and other ultrastructural studies have created a long standing quandary, which I have addressed and resolved using spectroscopic electron microscopy and statistical analyses of nucleosome images in a study of nucleosome structure with ionic environment.

scholarly journals Three-Dimensional Printing of Hydroxyapatite Composites for Biomedical Application

Crystals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 353
Author(s):  
Yanting Han ◽  
Qianqian Wei ◽  
Pengbo Chang ◽  
Kehui Hu ◽  
Oseweuba Valentine Okoro ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
3D Printing ◽  
Biomedical Application ◽  
Three Dimensional ◽  
Antibacterial Properties ◽  
Natural Polymers ◽  
Three Dimensional Printing ◽  
3D Printed ◽  
Dental Applications ◽  
Hard Tissue Engineering

Hydroxyapatite (HA) and HA-based nanocomposites have been recognized as ideal biomaterials in hard tissue engineering because of their compositional similarity to bioapatite. However, the traditional HA-based nanocomposites fabrication techniques still limit the utilization of HA in bone, cartilage, dental, applications, and other fields. In recent years, three-dimensional (3D) printing has been shown to provide a fast, precise, controllable, and scalable fabrication approach for the synthesis of HA-based scaffolds. This review therefore explores available 3D printing technologies for the preparation of porous HA-based nanocomposites. In the present review, different 3D printed HA-based scaffolds composited with natural polymers and/or synthetic polymers are discussed. Furthermore, the desired properties of HA-based composites via 3D printing such as porosity, mechanical properties, biodegradability, and antibacterial properties are extensively explored. Lastly, the applications and the next generation of HA-based nanocomposites for tissue engineering are discussed.

scholarly journals Reversal of senescence-associated beta-galactosidase expression during in vitro three-dimensional tissue-engineering of human chondrocytes in a polymer scaffold

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shojiro Katoh ◽  
Atsuki Fujimaru ◽  
Masaru Iwasaki ◽  
Hiroshi Yoshioka ◽  
Rajappa Senthilkumar ◽  
...  
Keyword(s):  
Regenerative Medicine ◽  
Replicative Senescence ◽  
Cultured Cells ◽  
Three Dimensional ◽  
Human Chondrocytes ◽  
Cartilage Tissue ◽  
Optimal Method ◽  
Beta Galactosidase

AbstractRegenerative medicine applications require cells that are not inflicted with senescence after in vitro culture for an optimal in vivo outcome. Methods to overcome replicative senescence include genomic modifications which have their own disadvantages. We have evaluated a three-dimensional (3D) thermo-reversible gelation polymer (TGP) matrix environment for its capabilities to reverse cellular senescence. The expression of senescence-associated beta-galactosidase (SA-βgal) by human chondrocytes from osteoarthritis-affected cartilage tissue, grown in a conventional two-dimensional (2D) monolayer culture versus in 3D-TGP were compared. In 2D, the cells de-differentiated into fibroblasts, expressed higher SA-βgal and started degenerating at 25 days. SA-βgal levels decreased when the chondrocytes were transferred from the 2D to the 3D-TGP culture, with cells exhibiting a tissue-like growth until 42–45 days. Other senescence associated markers such as p16INK4a and p21 were also expressed only in 2D cultured cells but not in 3D-TGP tissue engineered cartilage. This is a first-of-its-kind report of a chemically synthesized and reproducible in vitro environment yielding an advantageous reversal of aging of human chondrocytes without any genomic modifications. The method is worth consideration as an optimal method for growing cells for regenerative medicine applications.

Tissue-Engineered Cartilage in Three-Dimensional Cultured Chondrocytes by Ultrasound Stimulation and Collagen Sponge as Scaffold

2009 ◽  
Author(s):  
Toshihiko Shiraishi ◽  
Ietomo Matsunaga ◽  
Shin Morishita ◽  
Ryohei Takeuchi ◽  
Tomoyuki Saito ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Three Dimensional ◽  
Collagen Sponge ◽  
Cartilage Tissue ◽  
Mechanical Environment ◽  
Ultrasound Stimulation ◽  
Scaffold Structure ◽  
Matrix Production ◽  
Engineered Cartilage ◽  
Cultured Chondrocytes

This paper describes the effects of ultrasound stimulation on chondrocytes in three-dimensional culture in relation to the production of regenerative cartilage tissue, using collagen sponges as a carrier and supplementation with hyaluronic acid (used in the conservative treatment of osteoarthritis). It has been shown that cell proliferation and matrix production can be facilitated by considering the mechanical environment of the cultured chondrocytes and the mechanical properties of the scaffold structure used in the culture and of the stimulation used.

scholarly journals Physiological State and Learning Ability of Students in Normal and Virtual Reality Conditions: Complexity-Based Analysis (Preprint)

2020 ◽  
Author(s):  
Mohammad H Babini ◽  
Vladimir V Kulish ◽  
Hamidreza Namazi
Keyword(s):  
Virtual Reality ◽  
Fractal Theory ◽  
Physiological State ◽  
Three Dimensional ◽  
Physiological Signals ◽  
Learning Ability ◽  
Two Dimensional ◽  
Reality Condition ◽  
Computer Mediated ◽  
Dimensional Condition

BACKGROUND Education and learning are the most important goals of all universities. For this purpose, lecturers use various tools to grab the attention of students and improve their learning ability. Virtual reality refers to the subjective sensory experience of being immersed in a computer-mediated world, and has recently been implemented in learning environments. OBJECTIVE The aim of this study was to analyze the effect of a virtual reality condition on students’ learning ability and physiological state. METHODS Students were shown 6 sets of videos (3 videos in a two-dimensional condition and 3 videos in a three-dimensional condition), and their learning ability was analyzed based on a subsequent questionnaire. In addition, we analyzed the reaction of the brain and facial muscles of the students during both the two-dimensional and three-dimensional viewing conditions and used fractal theory to investigate their attention to the videos. RESULTS The learning ability of students was increased in the three-dimensional condition compared to that in the two-dimensional condition. In addition, analysis of physiological signals showed that students paid more attention to the three-dimensional videos. CONCLUSIONS A virtual reality condition has a greater effect on enhancing the learning ability of students. The analytical approach of this study can be further extended to evaluate other physiological signals of subjects in a virtual reality condition.

scholarly journals An efficient polymer cocktail-based transportation method for cartilage tissue, yielding chondrocytes with enhanced hyaline cartilage expression during in vitro culturing

2021 ◽  
Author(s):  
Shojiro Katoh ◽  
Hiroshi Yoshioka ◽  
Shoji Suzuki ◽  
Hiroyuki Nakajima ◽  
Masaru Iwasaki ◽  
...  
Keyword(s):  
Cultured Cells ◽  
Hyaline Cartilage ◽  
Three Dimensional ◽  
Cartilage Tissue ◽  
Human Cartilage ◽  
Tissue Samples ◽  
Chondrocyte Implantation ◽  
Initial Processing ◽  
Regenerative Therapies

Chondrocytes are used in cell-based therapies such as autologous chondrocyte implantation (ACI) and matrix-associated cartilage implantation (MACI). To transport the cartilage tissue to the laboratory for in vitro culturing, phosphate-buffered saline (PBS), Euro-Collins solution (ECS) and Dulbecco Modified Eagle Medium (DMEM) are commonly employed at 4-8 deg C. In this study, eight samples of human cartilage biopsy tissues from elderly patients with severe osteoarthritis undergoing arthroscopy, which would otherwise have been discarded, were used. The cartilage tissue samples were compared to assess the cell yield between two transportation groups: i) a thermo-reversible gelation polymer (TGP) based method without cool preservation (~25 deg C) and ii) ECS transport at 4 deg C. These samples were subjected to in vitro culture in a two-dimensional (2D) monolayer for two weeks and subsequently in a three-dimensional (3D) TGP scaffold for six weeks. The cell count obtained from the tissues transported in TGP was higher (0.2 million cells) than those transported in ECS (0.08 million cells) both after initial processing and after in vitro culturing for 2 weeks in 2D (18 million cells compared with 10 million cells). In addition, mRNA quantification demonstrated significantly higher expression of Col2a1 and SOX-9 in 3D-TGP cultured cells and lower expression of COL1a1 in RT-PCR, characteristic of the hyaline cartilage phenotype, than in 2D culture. This study confirms that the TGP cocktail is suitable for both the transport of human cartilage tissue and for in vitro culturing to yield better-quality cells for use in regenerative therapies.

Experimental Observation of the Sequence of Tibial Plateau Chondrocyte and Matrix Degeneration in Spontaneous Osteoarthritis in Guinea Pigs

2020 ◽  
Author(s):  
XIAOJIAN WANG ◽  
XIAOJIAN Wang ◽  
Lei Wei ◽  
Yan Xue ◽  
Rong-shan Li
Keyword(s):  
Knee Osteoarthritis ◽  
Guinea Pigs ◽  
Tibial Plateau ◽  
Caspase 3 ◽  
Physiological State ◽  
Research Society ◽  
Cartilage Tissue ◽  
Knee Oa ◽  
The Matrix ◽  
Osteoarthritis Research Society

Abstract Background To observe the sequence of chondrocyte degeneration and matrix degradation in the superficial surface cartilage of the tibial plateau in guinea pigs with spontaneous knee osteoarthritis (OA).Methods Forty guinea pigs were euthanized at the ages of 10 months (n=20) and 12 months (n=20). The degree of degeneration of the tibial plateau cartilage was evaluated by Osteoarthritis Research Society International (OARSI) score.The levels of MMP-13 and Caspase-3 in the chondrocytes were detected by immunohistochemistry (IHC). The serum concentration of CTX-II was measured and compared.Western blot analysis was used to detect the levels of MMP-13 and Caspase-3 in the cartilage tissue.Results The OARSI score in the 10-month-old group(6.4±1.7) was lower than that in the 12-month-old group(12.7±3.2)(P＜0.05). Immunohistochemical staining confirmed the levels of MMP-13(10-month-old,6.1±2.0;12-month-old,5.8±1.6) and Caspase-3(10-month-old,2.6±0.6;12-month-old,2.8±0.9) in two groups appeared to be nonsignificant (all P＜0.05).The serum CTX-II in the 10-month-old group(8.6±1.2) was lower than that in the 12-month-old group(13.7±2.3) (P＜0.05). The western blot results confirmed the levels of MMP-13(10-month-old,0.82±0.21;12-month-old,0.86±0.27) and Caspase-3(10-month-old,0.22±0.07;12-month-old,0.20±0.08) in two groups appeared to be nonsignificant (all P＜0.05).Conclusion The superficial chondrocytes of the tibial plateau first appeared to be hypertrophic and then apoptotic, and the matrix was further degraded when spontaneous knee osteoarthritis occurred in guinea pigs.Changes in the physiological state of chondrocytes are the initiating factors in the pathogenesis of knee OA.

scholarly journals Three-dimensional cartilage tissue regeneration system harnessing goblet-shaped microwells containing biocompatible hydrogel

2019 ◽  
Vol 12 (1) ◽  
pp. 015019 ◽  
Author(s):  
Nopphadol Udomluck ◽  
Sung-Hwan Kim ◽  
Hyunjoo Cho ◽  
Joong Yull Park ◽  
Hansoo Park
Keyword(s):  
Tissue Regeneration ◽  
Three Dimensional ◽  
Cartilage Tissue ◽  
Regeneration System

scholarly journals Xanthan Gum–Konjac Glucomannan Blend Hydrogel for Wound Healing

Polymers ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 99 ◽  
Author(s):  
Andreia Alves ◽  
Sónia P. Miguel ◽  
André R.T.S. Araujo ◽  
María José de Jesús Valle ◽  
Amparo Sánchez Navarro ◽  
...  
Keyword(s):  
Xanthan Gum ◽  
Biomedical Application ◽  
Three Dimensional ◽  
High Water ◽  
Biological Properties ◽  
Konjac Glucomannan ◽  
Wound Dressings ◽  
Dimensional Structure ◽  
Future Application ◽  
High Water Content

Hydrogels are considered to be the most ideal materials for the production of wound dressings since they display a three-dimensional structure that mimics the native extracellular matrix of skin as well as a high-water content, which confers a moist environment at the wound site. Until now, different polymers have been used, alone or blended, for the production of hydrogels aimed for this biomedical application. From the best of our knowledge, the application of a xanthan gum–konjac glucomannan blend has not been used for the production of wound dressings. Herein, a thermo-reversible hydrogel composed of xanthan gum–konjac glucomannan (at different concentrations (1% and 2% w/v) and ratios (50/50 and 60/40)) was produced and characterized. The obtained data emphasize the excellent physicochemical and biological properties of the produced hydrogels, which are suitable for their future application as wound dressings.

Sign in / Sign up

Export Citation Format

Share Document