scholarly journals In Vivo Study of Osteochondral Defect Regeneration Using Innovative Composite Calcium Phosphate Biocement in a Sheep Model

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4471
Author(s):  
Lenka Kresakova ◽  
Jan Danko ◽  
Katarina Vdoviakova ◽  
Lubomir Medvecky ◽  
Zdenek Zert ◽  
...  
Keyword(s):  
Amino Acids ◽  
Calcium Phosphate ◽  
Osteochondral Defect ◽  
Articular Surface ◽  
Fibrous Tissue ◽  
Treated Group ◽  
Negative Control ◽  
Osteochondral Defects ◽  
Sheep Model

This study aimed to clarify the therapeutic effect and regenerative potential of the novel, amino acids-enriched acellular biocement (CAL) based on calcium phosphate on osteochondral defects in sheep. Eighteen sheep were divided into three groups, the treated group (osteochondral defects filled with a CAL biomaterial), the treated group with a biocement without amino acids (C cement), and the untreated group (spontaneous healing). Cartilages of all three groups were compared with natural cartilage (negative control). After six months, sheep were evaluated by gross appearance, histological staining, immunohistochemical staining, histological scores, X-ray, micro-CT, and MRI. Treatment of osteochondral defects by CAL resulted in efficient articular cartilage regeneration, with a predominant structural and histological characteristic of hyaline cartilage, contrary to fibrocartilage, fibrous tissue or disordered mixed tissue on untreated defect (p < 0.001, modified O’Driscoll score). MRI results of treated defects showed well-integrated and regenerated cartilage with similar signal intensity, regularity of the articular surface, and cartilage thickness with respect to adjacent native cartilage. We have demonstrated that the use of new biocement represents an effective solution for the successful treatment of osteochondral defects in a sheep animal model, can induce an endogenous regeneration of cartilage in situ, and provides several benefits for the design of future therapies supporting osteochondral defect healing.

scholarly journals The Morphological, Clinical and Radiological Outputs of the Preclinical Study After Treatment of the Osteochondral Lesions in the Porcine Knee Model Using Implantation of Scaffold Based on the of Calcium Phosphate Biocement

2021 ◽  
Vol 8 ◽  
Author(s):  
Katarína Vdoviaková ◽  
Ján Danko ◽  
Lenka Krešáková ◽  
Veronika Šimaiová ◽  
Eva Petrovová ◽  
...  
Keyword(s):  
Amino Acids ◽  
Calcium Phosphate ◽  
Subchondral Bone ◽  
Osteochondral Defect ◽  
Knee Joints ◽  
Cartilage Tissue ◽  
Osteochondral Defects ◽  
Animal Group ◽  
Native Cartilage ◽  
Stifle Joint

The symptomatic full-thickness cartilage lesions or cartilage degeneration leads to the destruction of the normal chondral architecture and bone structure in affected area, causes the osteoarthritis, and general damage to the health. Knee joints are most frequently affected by this condition. The permanent damage of the articular cartilage and subchondral bone has motivated many scientists and clinicians to explore new methods of regeneration of osteochondral defects, such as novel materials. We studied the potential of the biocement based on calcium phosphate consisting of a mixture of four amino acids (glycine, proline, hydroxyproline and lysine) in the regenerating process of the artificially created osteochondral defect on the porcine medial femoral condyle in the stifle joint. The mass ratio of the amino acids in biocement CAL was 4:2:2:1. The Ca/P ratio in cement was 1.67 which correspond with ratio in hydroxyapatite. We compared the results with spontaneous healing of an artificially created cyst with that of the healthy tissue. The animal group treated with biocement paste CAL presented completely filled osteochondral defects. The results were confirmed by histological and radiological assessments, which have shown regenerated chondral and bone tissue in the examined knee joints. Macroscopic evaluation showed that neocartilage was well integrated with the adjacent native cartilage in animal group with biocement CAL, compared with healing of the artificial cyst, where treated cartilage surfaces were visibly lower than the surrounding native cartilage surface and a border between native and restored tissue was apparent. The qualitative assessment of the implant histology specimens showed full regeneration of the hyaline cartilage and subchondral bone in animals with biocement CAL. The artificial cyst group showed remarkable fibrillation. The detailed MRI analysis of cross-section of osteochondral defect confirmed the complete cartilage and subchondral bone healing where the thickness of the regenerated cartilage was 1.5 mm. The MRI imaging of defects in the artificial cyst group showed incomplete healing, neo cartilage tissue reduced up to 50%.

scholarly journals Peri-implant cartilage and bone histological changes following treatment of focal osteochondral defects in the femoral head with polyether ether ketone implants versus cobalt chromium molybdenum alloy implants: assessment in a goat model

2020 ◽  
Author(s):  
Zhiguo Yuan ◽  
Wei Zhang ◽  
Xiangchao Meng ◽  
Jue Zhang ◽  
Teng TengLong ◽  
...  
Keyword(s):  
Femoral Head ◽  
Osteochondral Defect ◽  
Osteochondral Defects ◽  
Cobalt Chromium ◽  
Cocrmo Alloy ◽  
Polyether Ether Ketone ◽  
Histological Score ◽  
Ether Ketone ◽  
Cobalt Chromium Molybdenum

Abstract Objective: This study aimed to quantitatively investigate the peri-implant histology of applying defect-size polyether ether ketone (PEEK) implant for the treatment of localized osteochondral defects in the femoral head and compared it with cobalt chromium molybdenum (CoCrMo) alloy implant.Methods: A femoral head osteochondral defect model was created in the left hips of goats (n=12). Defects were randomly treated by immediate placement of a PEEK (n=6) or CoCrMo implant (n=6). The un-operated right hip joints served as a control. Goats were sacrificed at 12 weeks. Periprosthetic cartilage quality was semi-quantitatively analyzed macroscopically and microscopically. Implant osseointegration was measured by micro-CT and histomorphometry.Results: The modified macroscopic articular evaluation score in the PEEK group was lower than that in the CoCrMo group (p<0.05), and the histological score of the periprosthetic and acetabular cartilage in the PEEK group was lower than that in the CoCrMo group (P<0.05). The mean bone-implant contact for PEEK implants was comparable with that for CoCrMo alloy implants at 12 weeks.Conclusions: A PEEK implant for the treatment of local osteochondral defect in the femoral head demonstrated effective fixation and superior in vivo cartilage protection compared with an identical CoCrMo alloy implant.

scholarly journals Identification of an N-Terminal Region of Sigma 54 Required for Enhancer Responsiveness

1998 ◽  
Vol 180 (21) ◽  
pp. 5619-5625 ◽  
Author(s):  
Adeela Syed ◽  
Jay D. Gralla
Keyword(s):  
Amino Acids ◽  
Single Point ◽  
Negative Control ◽  
Genetic Screens ◽  
Sigma 54 ◽  
Amino Acid Region ◽  
Enhancer Binding Protein ◽  
Activation Response

ABSTRACT Sigma 54 associates with bacterial core RNA polymerase and converts it into an enhancer-responsive enzyme. Deletion of the N-terminal 40 amino acids is known to result in loss of the ability to respond to enhancer binding proteins. In this work PCR mutagenesis and genetic screens were used to identify a small patch, from amino acids 33 to 37, that is required for proper response to activator in vivo. Site-directed single point mutants within this segment were constructed and studied. Two of these were defective in responding to the enhancer binding protein in vitro. The mutants could still direct the polymerase to bind to DNA and initiate transient melting. However, they failed in directing activator-dependent formation of a heparin-stable open complex. Thus, amino acid region 33 to 37 includes critical activation response determinants. This region overlaps the larger leucine patch negative-control region, suggesting that anti-inhibition and positive activation are closely coupled events.

In Vitro and In Vivo Evaluation of a Calcium Phosphate and Demineralized Bone Matrix Composite Biomaterial

2010 ◽  
Vol 5 ◽  
pp. 1-12 ◽  
Author(s):  
A. Rosenberg ◽  
Aliassghar Tofighi ◽  
N. Camacho ◽  
J. Chang
Keyword(s):  
Calcium Phosphate ◽  
Demineralized Bone Matrix ◽  
Bone Matrix ◽  
Negative Control ◽  
Water Soluble ◽  
Dense Area ◽  
Viscosity Modifier ◽  
Demineralized Bone

A new class of osteoconductive and osteoinductive combination biomaterials composed of calcium phosphate cement (CPC), demineralized bone matrix (DBM) and a water-soluble viscosity modifier were prepared and characterized in-vitro and in-vivo. In previous studies, a range of combinations formulations were tested in order to compare their performance characteristic. In-vitro characterization results show that the mechanical strength is decreased when the amount of DBM increases. However, DBM does not affect the CPC’s ability to set hard and convert to nanocrystalline apatitic calcium phosphate, which shares the chemical structure of natural bone as seen in x-ray diffraction. It is known that the DBM alone is osteoinductive. In-vivo osteoinductivity testing of the formulations in an intramuscular, athymic rat model demonstrated that the combination material is also osteoinductive. Two formulations were chosen for in-vivo efficacy testing based on the results of in-vitro and in-vivo characterization. These formulations were studied using rabbit critical-sized femoral core defect model. The formulations were composed of DBM with particle sizes of 250 to 710 μm, carboxymethyl-cellulose (CMC) as the viscosity modifier and weight percent compositions of 50% DBM/ 45% CPC/ 5% CMC and 60% DBM/ 30% CPC/ 10% CMC. Bone integration and healing was graded at 6, 12, and 24 weeks. The two formulations were compared to the gold standard autograft at 12 weeks and to an empty defect as the negative control at 24 weeks. Based on micro-computed topography (μCT), both formulations allowed for continuity of bone throughout the defect region at all time points. No differences in dense area fraction were seen between two formulations at 6 weeks (p = 0.8661). There was no significant statistical difference between the two formulations and autograft at 12 weeks (p = 0.2467). At 24 weeks, both formulations had significantly higher dense area fractions than empty controls (p = 0.0001). Histologically, the biology of the treatment areas appeared to have returned to normal by 24 weeks with CPC appearing to be the principal osteogenic inducer. In conclusion, these combinations of CPC and DBM offers significant advantages (handling, mechanical properties and osteoinductivity) over current DBM products and can be an effective alternative to autograft in healing of bone defects.

Experimental Study on the Osteoinduction of Calcium Phosphate Biomaterials In Vivo and the Capability of Supporting Osteoblast Proliferation In Vitro

2005 ◽  
Vol 288-289 ◽  
pp. 281-286 ◽  
Author(s):  
C.Y. Bao ◽  
P. Li ◽  
Yan Fei Tan ◽  
Y. Cao ◽  
Xiao Yan Lin ◽  
...  
Keyword(s):  
Experimental Study ◽  
Surface Modification ◽  
Calcium Phosphate ◽  
Treated Group ◽  
Osteoblast Proliferation ◽  
Thin Slices ◽  
Proliferation In Vitro ◽  
Ceramic Cylinder

The purpose of this study was to evaluate the response of osteoblasts to calcium phosphate with different surface modification, and to evaluate the osteoinductive capabilities of these biomaterials. 60HA/40α-TCP ceramics sintered at 1250oC was applied in this study. A ceramic cylinder with F5mm×8mm and slice with F10mm×1mm were prepared respectively. One third of the ceramics was used to form bone-like apatite (BLA), and the surface of another one third was modified with collagen. Osteoblasts (1×106/ml) were co-cultured with the three kinds of thin slices for 12h, 24h and 48h. SEM observation was applied to evaluate whether the surface modification and BLA formation could affect the attachment and proliferation of osteoblast in vitro. The three kinds of cylinder samples were implanted in dog muscle to evaluate their differences in osteoinduction. Cells grew in multi-layers and attached to the surface and proliferated well in the collagen and HA/TCP group. In the untreated and BLA precipitated groups, cells did not attach to the surface well. Osteoinduction was good in the BLA precipitated group and the amount of bone formed was higher; in the untreated group and collagen-treated group, no bone formation was observed in the tested period. This result indicated that the scaffold used in cell-materials composites in vitro and that in osteoinductive material based tissue engineering in vivo was not same.

In Vitro and In Vivo Surface Reactivity of Various Calcium Phosphate Coatings Deposited Using Electrostatic Spray Deposition (ESD)

2006 ◽  
Vol 309-311 ◽  
pp. 607-610
Author(s):  
Sander C.G. Leeuwenburgh ◽  
Joop G.C. Wolke ◽  
M.C. Siebers ◽  
J. Schoonman ◽  
John A. Jansen
Keyword(s):  
Calcium Phosphate ◽  
Fibrous Tissue ◽  
Tissue Response ◽  
Specific Chemical ◽  
Phosphate Coatings ◽  
Time Periods ◽  
Tissue Reactions ◽  
Calcium Phosphate Coatings

The dissolution and precipitation behavior of various porous, ESD-derived calcium phosphate coatings was investigated a) in vitro after soaking in Simulated Body Fluid (SBF) for several time periods (2, 4, 8, and 12 weeks), and b) in vivo after subcutaneous implantation in the back of goats for identical time periods. At the end of these studies, the physicochemical properties of the coated substrates were characterized by means of Scanning Electron Microscopy (SEM), XRay Diffraction (XRD), Fourier-Transform InfraRed spectroscopy (FTIR) and Energy Dispersive Spectroscopy (EDS). Moreover, part of the implants was prepared for light microscopical evaluation of the tissue response. In vitro, a highly bioactive behavior was observed for all ESD-coatings, characterized by the deposition of a thick and homogeneous carbonate hydroxyapatite precipitation layer on top of the porous coatings. Regarding the in vivo study, no adverse tissue reactions (toxic effects/inflammatory cells) were observed using light microscopy, and all coatings became surrounded by a thin, dense fibrous tissue capsule after implantation. The ESD-coatings degraded gradually at a dissolution rate depending on the specific chemical phase, thereby enabling synthesis of CaP coatings with a tailored degradation rate.

scholarly journals Repairing the Osteochondral Defect in Goat with the Tissue-Engineered Osteochondral Graft Preconstructed in a Double-Chamber Stirring Bioreactor

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Yang Pei ◽  
Jun-jun Fan ◽  
Xiao-qiang Zhang ◽  
Zhi-yong Zhang ◽  
Min Yu
Keyword(s):  
Mechanical Stimulation ◽  
Osteochondral Defect ◽  
Control Group ◽  
Osteochondral Defects ◽  
Reparative Effect ◽  
Group B ◽  
Better Than ◽  
Stimulation Of ◽  
Double Chamber

To investigate the reparative efficacy of tissue-engineered osteochondral (TEO) graft for repairing the osteochondral defect in goat, we designed a double-chamber stirring bioreactor to construct the bone and cartilage composites simultaneously in oneβ-TCP scaffold and observed the reparative effect in vivo. The osteochondral defects were created in goats and all the animals were divided into 3 groups randomly. In groups A, the defect was treated with the TEO which was cultured with mechanical stimulation of stir; in group B, the defect was treated with TEO which was cultured without mechanical stimulation of stir; in groups C, the defect was treated without TEO. At 12 weeks and 24 weeks after operation, the reparative effects in different groups were assessed and compared. The results indicated that the reparative effect of the TEO cultured in the bioreactor was better than the control group, and mechanical stimulation of stir could further improve the reparative effect. We provided a feasible and effective method to construct the TEO for treatment of osteochondral defect using autologous BMSCs and the double-chamber bioreactor.

scholarly journals Characterization of Properties, In Vitro and In Vivo Evaluation of Calcium Phosphate/Amino Acid Cements for Treatment of Osteochondral Defects

Materials ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 436
Author(s):  
Lubomir Medvecky ◽  
Maria Giretova ◽  
Radoslava Stulajterova ◽  
Jan Danko ◽  
Katarina Vdoviakova ◽  
...  
Keyword(s):  
Amino Acids ◽  
Calcium Phosphate ◽  
Subchondral Bone ◽  
Hyaline Cartilage ◽  
Healing Process ◽  
Complex Mixture ◽  
Surrounding Tissue ◽  
Osteochondral Defects ◽  
Post Surgery ◽  
Defect Sites

Novel calcium phosphate cements containing a mixture of four amino acids, glycine, proline, hydroxyproline and either lysine or arginine (CAL, CAK) were characterized and used for treatment of artificial osteochondral defects in knee. It was hypothesized that an enhanced concentration of extracellular collagen amino acids (in complex mixture), in connection with bone cement in defect sites, would support the healing of osteochondral defects with successful formation of hyaline cartilage and subchondral bone. Calcium phosphate cement mixtures were prepared by in situ reaction in a planetary ball mill at aseptic conditions and characterized. It was verified that about 30–60% of amino acids remained adsorbed on hydroxyapatite particles in cements and the addition of amino acids caused around 60% reduction in compressive strength and refinement of hydroxyapatite particles in their microstructure. The significant over-expression of osteogenic genes after the culture of osteoblasts was demonstrated in the cement extracts containing lysine and compared with other cements. The cement pastes were inserted into artificial osteochondral defects in the medial femoral condyle of pigs and, after 3 months post-surgery, tissues were analyzed macroscopically, histologically, immunohistochemically using MRI and X-ray methods. Analysis clearly showed the excellent healing process of artificial osteochondral defects in pigs after treatment with CAL and CAK cements without any inflammation, as well as formation of subchondral bone and hyaline cartilage morphologically and structurally identical to the original tissues. Good integration of the hyaline neocartilage with the surrounding tissue, as well as perfect interconnection between the neocartilage and new subchondral bone tissue, was demonstrated. Tissues were stable after 12 months’ healing.

Evaluation of Antitumor Activity and Hepatoprotective Effect of Mitomycin C Solubilized in Chamomile Oil Nanoemulsion

2019 ◽  
Vol 19 (10) ◽  
pp. 1232-1242
Author(s):  
Waad A. Al-Otaibi ◽  
Mayson H. Alkhatib ◽  
Abdulwahab N. Wali
Keyword(s):  
Antitumor Activity ◽  
In Vitro Study ◽  
Ehrlich Ascites Carcinoma ◽  
Treated Group ◽  
Positive Control ◽  
Negative Control ◽  
Hepatoprotective Effect ◽  
Antineoplastic Effect

:The present study aimed to investigate the antitumor activity and hepatoprotective effect of the MTC, when combined with CHAM oil nanoemulsion (NE), (CHAM-MTC) on the tumor growth.Materials/Methods:The in vitro study assessed the antineoplastic effect of CHAM-MTC on the MCF-7 breast cancer cells while the in vivo therapeutic effectiveness and toxicities of CHAM-MTC were evaluated in Ehrlich Ascites Carcinoma (EAC) bearing mice. One hundred female Swiss albino mice, divided equally into non-EAC group (negative control), untreated EAC group (positive control) and three EAC groups received once intraperitoneal injection of 0.2ml CHAM-NE, 0.2ml Normal Saline (NS) contained MTC (1mg/kg) and 0.2ml CHAM-NE mixed with MTC (1mg/kg), respectively.Results:The in vitro results indicated that CHAM-NE could potentiate the effect of MTC in sub-effective concentrations since the half-maximal inhibitory concentration (IC50) was reduced by a factor of 21.94 when compared to the MTC-NS. The in vivo study revealed that mice treated with CHAM-MTC showed a significant increase in the median survival time (MST= 37 days) when compared to the MTC-NS treated group (MST= 29.50 days). In addition, CHAM-MTC showed protective ability against the oxidative stress and hepatic damage induced by EAC and MTC treatment.Conclusion:The combination of MTC with CHAM-NE could be valuable in enhancing the therapeutic efficacy of MTC against EAC and in eliminating MTC-induced hepatotoxicity.

Bioactive Calcium Phosphate Material for Dental Endodontic Treatment. Root Apical Deposition.

2006 ◽  
Vol 309-311 ◽  
pp. 1157-1160 ◽  
Author(s):  
Julia Bosco ◽  
Bénedicte Enkel ◽  
Valerie Armengol ◽  
G. Daculsi ◽  
Alain Jean ◽  
...  
Keyword(s):  
Calcium Phosphate ◽  
Bone Substitute ◽  
Ex Vivo ◽  
Human Model ◽  
Mineral Formation ◽  
Ceramic Suspension ◽  
Calcium Phosphate Ceramic ◽  
Sheep Model ◽  
Good Filling

An injectable bone substitute (IBS) made of a suspension of Calcium phosphate ceramic was used to filled dental root canal after removing of canal pulp. The aim of this study was to verify the ability of calcium phosphate ceramic suspension to fill the apical zone of teeth ex vivo (n=40) and in vivo in a sheep model (n=8). The results showed that injection is possible with a good level of BCP granules at the end of the root dental canal with extracted tooth. In vivo, the presence of blood pressure due to the pulpectomy is a negative parameter to allow a good filling. The scanning electron microscopy revealed mineral formation at the apex level with mineral tissue conduction between the BCP granules but only one tooth showed a good apical filling with a good sealing. The sealing of the apex seems to depend of the amount of BCP granules. Other experiments with other animal models closer to a Human model have to be performed before human trials.

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