scholarly journals Capacitive interdigitated system of high osteoinductive/conductive performance for personalized acting-sensing implants

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Bárbara M. de Sousa ◽  
Clara R. Correia ◽  
Jorge A. F. Ferreira ◽  
João F. Mano ◽  
Edward P. Furlani ◽  
...  
Keyword(s):  
Bone Growth ◽  
Proteomics Data ◽  
Dual Systems ◽  
Bioactive Coatings ◽  
Bone Implant ◽  
Sensing Systems ◽  
Mineral Deposition ◽  
Matrix Maturation ◽  
Related Proteins

AbstractReplacement orthopedic surgeries are among the most common surgeries worldwide, but clinically used passive implants cannot prevent failure rates and inherent revision arthroplasties. Optimized non-instrumented implants, resorting to preclinically tested bioactive coatings, improve initial osseointegration but lack long-term personalized actuation on the bone–implant interface. Novel bioelectronic devices comprising biophysical stimulators and sensing systems are thus emerging, aiming for long-term control of peri-implant bone growth through biointerface monitoring. These acting-sensing dual systems require high frequency (HF) operations able to stimulate osteoinduction/osteoconduction, including matrix maturation and mineralization. A sensing-compatible capacitive stimulator of thin interdigitated electrodes and delivering an electrical 60 kHz HF stimulation, 30 min/day, is here shown to promote osteoconduction in pre-osteoblasts and osteoinduction in human adipose-derived mesenchymal stem cells (hASCs). HF stimulation through this capacitive interdigitated system had significant effects on osteoblasts’ collagen-I synthesis, matrix, and mineral deposition. A proteomic analysis of microvesicles released from electrically-stimulated osteoblasts revealed regulation of osteodifferentiation and mineralization-related proteins (e.g. Tgfb3, Ttyh3, Itih1, Aldh1a1). Proteomics data are available via ProteomeXchange with the identifier PXD028551. Further, under HF stimulation, hASCs exhibited higher osteogenic commitment and enhanced hydroxyapatite deposition. These promising osteoinductive/conductive capacitive stimulators will integrate novel bioelectronic implants able to monitor the bone–implant interface and deliver personalized stimulation to peri-implant tissues.

scholarly journals Effects of bicarbonate/lactate-buffered neutral peritoneal dialysis fluids on angiogenesis-related proteins in patients undergoing peritoneal dialysis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Hiromichi Ueno ◽  
Tetsu Miyamoto ◽  
Hiroyuki Morimoto ◽  
Kenya Sanada ◽  
Ikutaro Furuno ◽  
...  
Keyword(s):  
Peritoneal Dialysis ◽  
Antibody Array ◽  
The Novel ◽  
Term Delivery ◽  
Cxc Chemokine ◽  
Related Proteins ◽  
Chemokine Family ◽  
Dialysis Fluids

Abstract Background In order to facilitate the safe and long-term delivery of peritoneal dialysis (PD), it is necessary to improve the biocompatibility of peritoneal dialysis fluids (PDFs). The novel bicarbonate/lactate-buffered neutral PDFs (B/L-PDFs) are expected to be improved biocompatible. This study evaluated the biocompatibility of B/L-PDFs by analysis on the profile of angiogenesis-related proteins in drained dialysate of patients undergoing PD. Methods Concentrations of 20 angiogenesis-related proteins in the dialysate were semi-quantitatively determined using a RayBio® Human Angiogenesis Antibody Array and were compared between B/L-PDFs and conventional lactate-buffered neutral PDFs (L-PDFs). Results The expression of growth-related oncogene (GRO α/β/γ), which belongs to the CXC chemokine family, decreased significantly after use of the B/L-PDFs compared to the L-PDFs (P = 0.03). The number of the proteins with lower level in the B/L-PDFs compared with L-PDFs was significantly negatively correlated with the PD duration (Spearman ρ = − 0.81, P = 0.004). Conclusion This study suggested that B/L-PDFs are more biocompatible than conventional PDFs.

The Coating of Bovine-Source Hydroxyapatite on Titanium Alloy (Ti-6Al-4V ELI) Using Electrophoretic Deposition for Biomedical Application

2020 ◽  
Vol 1000 ◽  
pp. 97-106
Author(s):  
Dian Juliadmi ◽  
Nuzul Ficky Nuswantoro ◽  
Hidayatul Fajri ◽  
Irma Yulia Indriyani ◽  
Jon Affi ◽  
...  
Keyword(s):  
Particle Size ◽  
Titanium Alloy ◽  
Electrophoretic Deposition ◽  
Bone Growth ◽  
Biomedical Application ◽  
Size Variation ◽  
Bone Implant ◽  
Bioactive Substance ◽  
Good Coating ◽  
Bone Apatite

Research about the utilization of titanium alloy (Ti-6Al-4V ELI) as implant material in the treatment of orthopedic cases had been increasing. Health problems appear due to the drawbacks of using titanium. The lack of titanium using is bio-inertness characteristic, which decreasing its bioactivity and results in low bone growth and effect for implant failure. The titanium can be modified with coating on the surface using a bioactive substance that is natural-source hydroxyapatite. Bovine-source hydroxyapatite (bovineHA) contains apatite component that is similar to human bone apatite. The coating process was carried out using particle size variation (25 μm, 63 μm, and 125 μm) of bovineHA. The electrophoretic deposition (EPD) method was applied to coat hydroxyapatite with 10 volt for 5 minutes onto the titanium surface. The result showed that different size particles have an effect on coating properties. The coating composed by particle-sized 25 μm has better surface coverage (95.89%), indicating more particle mass (particle weight 6.97x103 μg) attached to surface material, thus resulting thick coating. The good coating characteristic using bovine-source hydroxyapatite with small particle size was expected can be used in biomedical applications due to fulfill the prerequisite of the bone implant.

scholarly journals Knockdown of MicroRNA-1 in the Hippocampus Ameliorates Myocardial Infarction Induced Impairment of Long-Term Potentiation

2018 ◽  
Vol 50 (4) ◽  
pp. 1601-1616 ◽  
Author(s):  
Ji-Chao Ma ◽  
Ming-Jing Duan ◽  
Ke-Xin Li ◽  
Das Biddyut ◽  
Shuai Zhang ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Sham Group ◽  
Long Term Potentiation ◽  
Stimulus Response ◽  
Protein Levels ◽  
Term Potentiation ◽  
Passive And Active Avoidance ◽  
Related Proteins

Backgrounds/Aims: It has been reported that myocardial infarction (MI) is a risk factor for vascular dementia. However, the molecular mechanism remains largely unknown. Methods: MI mice were generated by ligation of the left coronary artery (LCA) for 4 weeks. Passive and active avoidance tests were performed to evaluate the cognitive ability of MI mice. A theta-burst stimulation (TBS) protocol was applied to elicit long-term potentiation (LTP) of the perforant pathway-dentate gyrus synapse (PP-DG). Western blot analysis was employed to assess protein levels. Results: In this study, we demonstrated that after 4 weeks of MI, C57BL/6 mice had significantly impaired memory. Compared with the sham group, in vivo physiological recording in the MI group revealed significantly decreased amplitude of population spikes (PS) with no effect on the latency and duration of the stimulus-response curve. The amplitude of LTP was markedly decreased in the MI group compared with the sham group. Further examination showed that the expression of the TBS-LTP-related proteins BDNF, GluA1 and phosphorylated GluA1 were all decreased in the MI group compared with those in the sham group. Strikingly, all these changes were prevented by hippocampal stereotaxic injection of an anti-miR-1 oligonucleotide fragment carried by a lentivirus vector (lenti-pre-AMO-1). Conclusion: MI induced cognitive decline and TBS-LTP impairment, and decreased BDNF and GluA1 phosphorylation levels from overexpression of miR-1ated were involved in this process.

scholarly journals Long Term Cyclic Pamidronate Reduces Bone Growth by Inhibiting Osteoclast Mediated Cartilage-to-Bone Turnover in the Mouse

2008 ◽  
Vol 2 (1) ◽  
pp. 121-125 ◽  
Author(s):  
K.D Evans ◽  
L.E Sheppard ◽  
D.I Grossman ◽  
S.H Rao ◽  
R.B Martin ◽  
...  
Keyword(s):  
Bone Turnover ◽  
Growth Plate ◽  
Bone Growth ◽  
Cathepsin K ◽  
Chondrocyte Apoptosis ◽  
Cell Numbers ◽  
Hypertrophic Chondrocyte ◽  
Osteoclast Function ◽  
And Function

Bisphosphonates, used to treat diseases exhibiting increased osteoclast activity, reduce longitudinal bone growth through an as yet undefined mechanism. Pamidronate, an aminobisphosphonate, was given weekly to mice at 0, 1.25, or 2.50 mg/kg/wk beginning at 4 weeks of age. At 12 weeks of age, humeral length, growth plate area, regional chondrocyte cell numbers, chondrocyte apoptosis, TRAP stained osteoclast number, and osteoclast function assessed by cathepsin K immunohistochemistry were quantified. Humeral length was decreased in pamidronate treated mice compared to vehicle control mice, and correlated with greater growth plate areas reflecting greater proliferative and hypertrophic chondrocyte cell numbers with fewer hypertrophic cells undergoing apoptosis. Pamidronate treatment increased TRAP stained osteoclast numbers yet decreased cathepsin K indicating that pamidronate repressed osteoclast maturation and function. The data suggest that long term cyclic pamidronate treatment impairs bone growth by inhibition of osteoclast maturation thereby reducing cartilage-to-bone turnover within the growth plate.

scholarly journals Targeting B cells to modify MS, NMOSD, and MOGAD

2020 ◽  
Vol 8 (1) ◽  
pp. e919
Author(s):  
Jonas Graf ◽  
Jan Mares ◽  
Michael Barnett ◽  
Orhan Aktas ◽  
Philipp Albrecht ◽  
...  
Keyword(s):  
B Cell ◽  
Case Series ◽  
Myelin Oligodendrocyte Glycoprotein ◽  
Clinical Development ◽  
B Cell Depletion ◽  
Phase 2 ◽  
Proven Efficacy ◽  
Advanced Stages ◽  
Related Proteins

Ocrelizumab, rituximab, ofatumumab, ublituximab, inebilizumab, and evobrutinib are immunotherapies that target various B cell–related proteins. Most of these treatments have proven efficacy in relapsing and progressive forms of MS and neuromyelitis optica spectrum disease (NMOSD) or are in advanced stages of clinical development. Currently, ocrelizumab and inebilizumab are licensed for treatment of MS and NMOSD, respectively. This part of the review focuses on monoclonal antibody B cell–depleting strategies in NMOSD and the emerging related myelin oligodendrocyte glycoprotein (MOG) immunoglobulin G–associated disease (MOGAD). Case series and phase 2/3 studies in these inflammatory disorders are assessed. The safety profile of long-term B-cell depletion in MS, NMOSD, and MOGAD will be highlighted. Finally implications of the current coronavirus disease 2019 pandemic on the management of patients with these disorders and the use of B cell–depleting agents will be discussed.

Vertical Bone Growth after Autotransplantation of Mature Third Molars: 2 Case Reports with Long-term Follow-up

2015 ◽  
Vol 41 (8) ◽  
pp. 1371-1374 ◽  
Author(s):  
Sunil Kim ◽  
Seung-Jong Lee ◽  
Yooseok Shin ◽  
Euiseong Kim
Keyword(s):  
Bone Growth ◽  
Case Reports ◽  
Third Molars ◽  
Long Term Follow Up

scholarly journals Rac signaling in osteoblastic cells is required for normal bone development but is dispensable for hematopoietic development

Blood ◽  
2012 ◽  
Vol 119 (3) ◽  
pp. 736-744 ◽  
Author(s):  
Steven W. Lane ◽  
Serena De Vita ◽  
Kylie A. Alexander ◽  
Ruchan Karaman ◽  
Michael D. Milsom ◽  
...  
Keyword(s):  
Bone Growth ◽  
Bone Development ◽  
Long Bone ◽  
Perivascular Niche ◽  
Hematopoietic Stem ◽  
Hsc Niche ◽  
Rac1 Gtpase

Abstract Hematopoietic stem cells (HSCs) interact with osteoblastic, stromal, and vascular components of the BM hematopoietic microenvironment (HM) that are required for the maintenance of long-term self-renewal in vivo. Osteoblasts have been reported to be a critical cell type making up the HSC niche in vivo. Rac1 GTPase has been implicated in adhesion, spreading, and differentiation of osteoblast cell lines and is critical for HSC engraftment and retention. Recent data suggest a differential role of GTPases in endosteal/osteoblastic versus perivascular niche function. However, whether Rac signaling pathways are also necessary in the cell-extrinsic control of HSC function within the HM has not been examined. In the present study, genetic and inducible models of Rac deletion were used to demonstrate that Rac depletion causes impaired proliferation and induction of apoptosis in the OP9 cell line and in primary BM stromal cells. Deletion of Rac proteins caused reduced trabecular and cortical long bone growth in vivo. Surprisingly, HSC function and maintenance of hematopoiesis in vivo was preserved despite these substantial cell-extrinsic changes. These data have implications for therapeutic strategies to target Rac signaling in HSC mobilization and in the treatment of leukemia and provide clarification to our evolving concepts of HSC-HM interactions.

Functionalized Calcium Phosphate-based Nanoparticles for the Treatment of Osteoporosis

2005 ◽  
Vol 873 ◽  
Author(s):  
Balasundaram G ◽  
Sato M ◽  
Webster TJ
Keyword(s):  
Calcium Phosphate ◽  
Bone Formation ◽  
Amorphous Calcium Phosphate ◽  
Bone Growth ◽  
Osteoporotic Bone ◽  
Amino Groups ◽  
Calcium Phosphate Nanoparticles ◽  
Bioactive Agents ◽  
Bone Growth Factor

AbstractIn an effort to decrease the number of problems associated with osteoporosis, the long-term goal of the present study is to design calcium phosphate-based nanoparticles that specifically attach to areas of low bone density and once attached, allow for the targeted release of bioactive agents that can quickly increase bone formation. Efforts are focused on nanoparticles of calcium phosphate-based materials since they are similar in size and chemistry to the major inorganic components of bone. As a first step in this research, the objective of the present study was to synthesize nanoparticles of crystalline hydroxyapatite (or HA) and amorphous calcium phosphate. Crystalline HA is stable under physiological fluids and, thus, will release embedded bioactive agents slowly. Alternatively, amorphous calcium phosphate is highly biodegradable and will, thus, release embedded bioactive agents quickly. A further objective of the present study was to functionalize such inorganic biodegradable materials with amino groups which would allow for the subsequent attachment of entities to direct such nanoparticles to osteoporotic bone and increased bone formation once attached. One promising approach to direct the nanoparticles to osteoporotic bone is to attach antibodies to pentosidine on the nanoparticles since pentosidine is present in higher amounts in osteoporotic compared to healthy bone. A promising approach to increase bone growth once nanoparticles attach to osteoporotic bone, is to embed nanoparticles with regions of the bone growth factor: bone morphogenic protein-2 (or BMP-2). Results of this study demonstrated the successful synthesis of both crystalline HA and amorphous calcium phosphate nanoparticles. Furthermore, results showed that these nanoparticles can be functionalized with versatile amino groups. In this manner, this study takes the first steps toward utilizing calcium phosphate based nanoparticles to reverse bone loss associated with osteoporosis.

Comparison of femur strain under different loading scenarios: Experimental testing

2020 ◽  
Vol 235 (1) ◽  
pp. 17-27
Author(s):  
Ievgen Levadnyi ◽  
Jan Awrejcewicz ◽  
Yan Zhang ◽  
Yaodong Gu
Keyword(s):  
Finite Element ◽  
Finite Element Model ◽  
Strain Distribution ◽  
Element Model ◽  
Surface Strain ◽  
Image Correlation ◽  
Loading Conditions ◽  
Bone Implant ◽  
Bone Stiffness

Bone fracture, formation and adaptation are related to mechanical strains in bone. Assessing bone stiffness and strain distribution under different loading conditions may help predict diseases and improve surgical results by determining the best conditions for long-term functioning of bone-implant systems. In this study, an experimentally wide range of loading conditions (56) was used to cover the directional range spanned by the hip joint force. Loads for different stance configurations were applied to composite femurs and assessed in a material testing machine. The experimental analysis provides a better understanding of the influence of the bone inclination angle in the frontal and sagittal planes on strain distribution and stiffness. The results show that the surface strain magnitude and stiffness vary significantly under different loading conditions. For the axial compression, maximal bending is observed at the mid-shaft, and bone stiffness is also maximal. The increased inclination leads to decreased stiffness and increased magnitude of maximum strain at the distal end of the femur. For comparative analysis of results, a three-dimensional, finite element model of the femur was used. To validate the finite element model, strain gauges and digital image correlation system were employed. During validation of the model, regression analysis indicated robust agreement between the measured and predicted strains, with high correlation coefficient and low root-mean-square error of the estimate. The results of stiffnesses obtained from multi-loading conditions experiments were qualitatively compared with results obtained from a finite element analysis of the validated model of femur with the same multi-loading conditions. When the obtained numerical results are qualitatively compared with experimental ones, similarities can be noted. The developed finite element model of femur may be used as a promising tool to estimate proximal femur strength and identify the best conditions for long-term functioning of the bone-implant system in future study.

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