scholarly journals DIFFERENCES OF BONE REGENERATION USING BOVINE HYDROXYAPATITE AND BOVINE HYDROXYAPATITE WITH FREEZE-DRIED PLATELET RICH PLASMA ALLOGRAFT IN BONE DEFECT OF FEMORAL WHITE RABBIT

Author(s):  
Mouli Edward ◽  
Henry Dominica ◽  
Ferdiansyah Mahyudin ◽  
Fedik Abdul Rantam

Background: Bone defects to date have been a significant problem in the Orthopedics field. Hydroxyapatite is a bone graft that is often chosen if it has osteoconductive properties. Platelet-rich plasma (PRP) has a higher platelet concentration than the concentration in normal blood, capable of providing many bioactive molecules in physiological proportions. Hydroxyapatite given freeze-dried PRP is expected to create a graft that can strengthen the matrix while promoting osteoinduction.Methods: This study compares the effects of regeneration on the bone between bovine hydroxyapatite (BHA) and bovine hydroxyapatite with freeze-dried platelet-rich plasma (FD-PRP) as a bone graft in bone defect of the femoral white rabbit. The 12 equal New Zealand white rabbits aged 6-9 months are divided into two groups. Bone defects were made in the lower femoral meta-diaphysis with a diameter of 2.5 mm. The defects were filled with BHA with FD-PRP allograft in the treatment group and BHA in the control group. Both groups will be sacrificed in the third and sixth weeks, then evaluated histologically for microvascular structure, osteoblasts, woven bone, type-I collagen, osteocalcin, alkaline phosphatase, and immunoglobulin G.Results: During the evaluation in week 3 and 6, microvascular structure, osteoblast, and type-I collagen decreased in both groups with insignificant differences (p>0.05). Woven bone, osteocalcin, and immunoglobulin G increased in the treatment group but was not significant (p>0.05). Alkaline phosphatase increased higher in the treatment group, with a considerable difference in the sixth week (p=0.008).Conclusion: The elevation in the production of woven bone, osteocalcin, and alkaline phosphatase at the third and sixth-week evaluations highlight the possibility that administering BHA given FD-PRP may have contributed to the healing of bone defects.

2014 ◽  
Vol 26 (01) ◽  
pp. 1450005 ◽  
Author(s):  
Tingwei Bao ◽  
Huiming Wang ◽  
Wentao Zhang ◽  
Xuefeng Xia ◽  
Jiabei Zhou ◽  
...  

Purpose: Plasmid loading into scaffolds to enhance sustained release of growth factors is an important focus of regenerative medicine. The aim of this study was to build gene-activated matrices (GAMs) and examine the bone augmentation properties. Methods: Generation 5 polyamidoamine dendrimers (G5 dPAMAM)/plasmid recombinant human bone morphogenetic protein-2 (rhBMP-2) complexes were immobilized into beta-tricalcium phosphate (β-TCP)/type I collagen porous scaffolds. After cultured with rat mesenchymal stem cells (rMSCs), transfection efficiencies were examined. The secretion of rhBMP-2 and alkaline phosphatase (ALP) were detected to evaluate the osteogenic properties. Scanning electron microscopy (SEM) was used to observe attachment and proliferation. Moreover, we applied these GAMs directly into freshly created segmental bone defects in rat femurs, and their osteogenic efficiencies were evaluated. Results: Released plasmid complexes were transfected into stem cells and were expressed, which caused osteogenic differentiations of rat mesenchymal stem cells (rMSCs). SEM analysis showed excellent cell attachment. Bioactivity of plasmid rhBMP-2 was maintained in vivo, and the X-ray observation, histological analysis and immunohistochemistry (IHC) of bone tissue demonstrated that the bone healing in segmental femoral defects was enhanced by implantation of GAMs. Conclusions: Such biomaterials offer therapeutic opportunities in critical-sized bone defects.


2005 ◽  
Vol 94 (07) ◽  
pp. 107-114 ◽  
Author(s):  
Christelle Lecut ◽  
Martine Jandrot-Perrus ◽  
Marion A. H. Feijge ◽  
Judith M. E. M. Cosemans ◽  
Johan W. M. Heemskerk

SummaryThe role of collagens and collagen receptors was investigated in stimulating platelet-dependent thrombin generation. Fibrillar type-I collagens, including collagen from human heart, were most potent in enhancing thrombin generation, in a way dependent on exposure of phosphatidylserine (PS) at the platelet surface. Soluble, non-fibrillar type-I collagen required pre-activation of integrin α2β1 with Mn2+ for enhancement of thrombin generation. With all preparations, blocking of glycoprotein VI (GPVI) with 9O12 antibody abrogated the collagen-enhanced thrombin generation, regardless of the α2β1 activation state. Blockade of α2β1 alone or antagonism of autocrine thromboxane A2 and ADP were less effective. Blockade of αIIbβ3 with abciximab suppressed thrombin generation in platelet-rich plasma, but this did not abolish the enhancing effect of collagens. The high activity of type-I fibrillar collagens in stimulating GPVI-dependent procoagulant activity was confirmed in whole-blood flow studies, showing that these collagens induced relatively high expression of PS. Together, these results indicate that: i) fibrillar type-I collagen greatly enhances thrombin generation, ii) GPVI-induced platelet activation is principally responsible for the procoagulant activity of fibrillar and non-fibrillar collagens, iii) α2β1 and signaling via autocrine mediators facilitate and amplify this GPVI activity, and iv) αIIbβ3 is not directly involved in the collagen effect.


2020 ◽  
Vol 26 (12) ◽  
pp. 1477-1485
Author(s):  
Wen-bin Zheng ◽  
Yi Dai ◽  
Jing Hu ◽  
Di-chen Zhao ◽  
Ou Wang ◽  
...  

Objective: Duchenne muscular dystrophy (DMD) is a severe X-linked progressive neuromuscular disease that brings a significantly increased risk of osteoporosis and bone fractures. We prospectively evaluated the effects of oral and intravenous bisphosphonates on the bones of children with DMD. Methods: This study included a total of 52 children with DMD. They were divided into zoledronic acid (ZOL), alendronate (ALN), and control groups according to bone mineral density (BMD) and history of fragility fractures. For 2 years, all patients took calcium, vitamin D, and calcitriol. Meanwhile, 17 patients received infusions of ZOL, and 18 patients received ALN. BMD, serum levels of alkaline phosphatase (ALP) and the cross-linked C-telopeptide of type I collagen (β-CTX) were evaluated. Results: After 24 months of treatment, the percentage changes in lumbar spine BMD were 23.2 ± 9.7% and 23.6 ± 8.8% in the ZOL and ALN groups (all P<.01 vs. baseline). The increases did not differ between the ZOL and ALN groups, but were significantly larger than those of the control group ( P<.01). Serum β-CTX and ALP levels, respectively, were decreased by 44.4 ± 18.0% and 31.9 ± 26.7% in the ZOL group and by 36.0 ± 20.3% and 25.8 ± 14.4% in the ALN group (all P<.01 vs. baseline). Conclusion: Zoledronic acid and alendronate had similar protective effects to increase bone mineral density and reduce bone resorption in children with DMD, which were superior to treatment of calcium, vitamin D, and calcitriol. Abbreviations: 25OHD = 25 hydroxyvitamin D; ALN = alendro-nate; ALP = alkaline phosphatase; ALT = alanine aminotransferase; BMD = bone mineral density; BP = bisphosphonate; Ca = calcium; β-CTX = cross-linked C-telopeptide of type I collagen; DMD = Duchenne muscular dystrophy; FN = femoral neck; GC = glucocorticoid; LS = lumbar spine; ZOL = zoledronic acid


2007 ◽  
Vol 12 (2) ◽  
pp. 307-312 ◽  
Author(s):  
Maria Helena Santos ◽  
Ana Paula M. Shaimberg ◽  
Patricia Valerio ◽  
Alfredo M. Goes ◽  
Maria de Fátima Leite ◽  
...  

The cytocompatibility of synthetic hydroxyapatite/collagen composites alone or doped with Zn+2 was tested by using primary culture of osteoblasts. The hydroxyapatite (HAP) was synthesized having calcium hydroxide and orthophosphoric acid as precursors. A new HAP composite was developed adding 1.05 w% of Zn(NO3)2.6H2O forming HAPZn. The pure type I collagen (COL) was obtained from bovine pericardium by enzymatic digestion method. The HAP/COL and HAPZn/COL composites were developed and characterized by SEM/EDS. The cell viability and alkaline phosphatase activity in the presence of composites were evaluated by MTT assay and NBT-BCIP assay, respectively, and compared to osteoblastic cells of the control. Three individual experiments were accomplished in triplicates and submitted to the variance analysis and Bonferroni’s post-test with statistically significant at p<0.05. The HAPZn/COL composite did not stimulate the proliferation and increasing of alkaline phosphatase activity of the osteoblastic cells. The tested composites did not alter the cellular viability neither caused alterations in the cellular morphology in 72 h showing adequate properties for biological applications.


1998 ◽  
Vol 44 (8) ◽  
pp. 1621-1628 ◽  
Author(s):  
Per Magnusson ◽  
Lasse Larsson ◽  
Gunnar Englund ◽  
Brita Larsson ◽  
Peter Strang ◽  
...  

Abstract We compared clodronate with placebo administration in 42 primarily or secondarily hormone-refractory prostate cancer patients with skeletal metastases and persisting pain. Serum total alkaline phosphatase (ALP), bone ALP isoforms, osteocalcin, cross-linked carboxy-terminal telopeptide of type I collagen, and prostate-specific antigen were analyzed before and after 1 month of treatment. Six ALP isoforms were quantified by HPLC: one bone/intestinal, two bone (B1, B2), and three liver ALP isoforms. The most apparent difference compared with healthy males was observed for the bone ALP isoform B2. Patients and healthy males had a B2 activity corresponding to 75% and 35% of the total ALP activity, respectively (P &lt;0.0001). We propose that the different bone ALP isoforms reflect different stages of osteoblast differentiation during the extracellular matrix maturation phase of osteogenesis. All bone markers except osteocalcin increased after 1 month of clodronate administration. These increases were associated with pain only in the upper part of the body. We suggest that the uptake of clodronate by the skeleton was not uniform during our treatment period.


Author(s):  
I. V. Yannas ◽  
D. S. Tzeranis ◽  
B. A. Harley ◽  
P. T. C. So

A small number of type I collagen–glycosaminoglycan scaffolds (collagen–GAG scaffolds; CGSs) have unusual biological activity consisting primarily in inducing partial regeneration of organs in the adult mammal. Two of these are currently in use in a variety of clinical settings. CGSs appear to induce regeneration by blocking the adult healing response, following trauma, consisting of wound contraction and scar formation. Several structural determinants of biological activity have been identified, including ligands for binding of fibroblasts to the collagen surface, the mean pore size (which affects ligand density) and the degradation rate (which affects the duration of the wound contraction-blocking activity by the scaffold). Processing variables that affect these determinants include the kinetics of swelling of collagen fibres in acetic acid, freezing of the collagen–GAG suspension and cross-linking of the freeze-dried scaffold. Recent developments in the processing of CGSs include fabrication of scaffolds that are paucidisperse in pore size, scaffolds with gradients in physicochemical properties (and therefore biological activity) and scaffolds that incorporate a mineral component. Advances in the characterization of the pore structure of CGSs have been made using confocal and nonlinear optical microscopy (NLOM). The mechanical behaviour of CGSs, as well as the resistance to degradative enzymes, have been studied. Following seeding with cells (typically fibroblasts), contractile forces in the range 26–450 nN per cell are generated by the cells, leading to buckling of scaffold struts. Ongoing studies of cell-seeded CGSs with NLOM have shown an advantage over the use of confocal microscopy due to the ability of the former method to image the CGS surfaces without staining (which alters its surface ligands), reduced cell photodamage, reduced fluorophore photobleaching and the ability to image deeper inside the scaffold.


2006 ◽  
Vol 91 (11) ◽  
pp. 4453-4458 ◽  
Author(s):  
Mariateresa Sciannamblo ◽  
Gianni Russo ◽  
Debora Cuccato ◽  
Giuseppe Chiumello ◽  
Stefano Mora

Abstract Context: Patients with congenital adrenal hyperplasia (CAH) receive glucocorticoids as replacement therapy. Glucocorticoid therapy is the most frequent cause of drug-induced osteoporosis. Objective: The objective of the study was to evaluate bone mineral density (BMD) and bone metabolism in CAH patients. Design: This was a cross-sectional observational study. Setting: The study was conducted at a referral center for pediatric endocrinology. Patients and Other Participants: Thirty young patients with the classical form of CAH (aged 16.4–29.7 yr) treated with glucocorticoid from diagnosis (duration of treatment 16.4–29.5 yr) and 138 healthy controls (aged 16.0–30.0 yr) were enrolled. Main Outcome Measures: BMD was measured in the lumbar spine and whole body by dual-energy x-ray absorptiometry. Bone formation and resorption rates were estimated by serum measurements of bone-specific alkaline phosphatase and C-terminal telopeptide of type I collagen, respectively. Results: CAH patients were shorter than controls (women −6.8 and men −13.3 cm). Therefore, several methods were used to account for the effect of this difference on bone measurements. Whole-body BMD measurements were significantly lower, compared with controls (P &lt; 0.03), after controlling for height (on average −2.5% in females and −9.3% in male patients). No differences were found in lumbar spine measurements. Bone-specific alkaline phosphatase and C-terminal telopeptide of type I collagen serum concentrations were higher in CAH patients than control subjects (P &lt; 0.04). BMD measurements and bone metabolism markers did not correlate with the actual glucocorticoid dose or mean dose over the previous 7 yr. Conclusions: Young adult patients with the classical form of CAH have decreased bone density values, compared with healthy controls. This may put them at risk of developing osteoporosis early in life.


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