Proliferation Of Bone Tissue Research Articles

Promotion of bone osteogenic and regeneration by resveratrol-derived carbon dots in inflammatory environments via a one-step hydrothermal method

In the context of bone fractures, local inflammation complicates the healing process, adversely affecting the recovery of bone defects. This inflammatory response impedes the regenerative potential of stem cells and induces the differentiation of macrophages into the M1 type, thereby inhibiting bone regeneration. To address this issue, we synthesized carbon dots (CDs) using resveratrol and citric acid. These CDs demonstrated excellent water solubility and retained the anti-inflammatory properties of resveratrol. In an inflammatory environment co-cultured with resveratrol carbon dots (RES-CDs), we observed a reduction in inflammatory factors such as iNOS and an increase in anti-inflammatory factors like CD206. Alkaline phosphatase (ALP) activity, Alizarin Red staining, and immunofluorescence assays indicated that MC3T3 cells produced more calcium nodules after co-culture with RES-CDs, along with enhanced expression of bone formation factors BMP-2 and ALP. Additionally, real-time polymerase chain reaction (qRT-PCR) and immunofluorescence analysis demonstrated that RES-CDs could induce bone tissue proliferation and differentiation by upregulating ALP, BMP-2, OCN, and OPN. In a rat cranial defect model, RES-CDs promoted tissue healing and bone proliferation at weeks 1 and 4 post-surgery. These findings underscore the potential of resveratrol carbon dots in promoting bone tissue healing while mitigating inflammation, thereby offering a promising approach for nanocomposite materials in tissue repair.

Pulsed Electromagnetic Field Stimulators Efficacy for Noninvasive Bone Growth in Spine Surgery.

The growth of pulsed electromagnetic field (PEMF) therapy and its progress over the years for use in post-operative bone growth has been revolutionary in its effect on bone tissue proliferation and vascular flow. However, further progress in PEMF therapy has been difficult due to lack of more evidence-based understanding of its mechanism of action. Our objective was to review the current understanding of bone growth physiology, the mechanism of PEMF therapy action along with its application in spinal surgery and associated outcomes. The authors of this review examined multiple controlled, comparative, and cohort studies to compare fusion rates of patients undergoing PEMF stimulation. Examining spinal fusion rates, a rounded comparison of post-fusion outcomes with and without bone stimulator was performed. Results showed that postoperative spinal surgery PEMF stimulation had higher rates of fusion than control groups. Though PEMF therapy was proven more effective, multiple factors contributed to difficulty in patient compliance for use. Extended timeframe of treatment and cost of treatment were the main obstacles to full compliance. This review showed that PEMF therapy presented an increased rate of recovery in patients, supporting the use of these devices as an effective post-surgical aid. Given the recent advances in the development of PEMF devices, affordability and access will be much easier suited to the patient population, allowing for more readily available treatment options.

Zinc oxide nanocrystals as a nanoantibiotic and osteoinductive agent.

In this paper we aim to analyse the behaviour of ZnO nanocrystals (ZnO NCs), prepared with a new synthetic approach and not embedded in any composite matrix, for bone implant applications in vitro. In particular, we have developed a novel, fast and reproducible microwave-assisted synthesis, to obtain highly-crystalline, round-shaped ZnO NCs of 20 nm in diameter as an extremely-stable colloidal solution in ethanol. The nanocrystals were also partially chemically functionalized by anchoring amino-propyl groups to the ZnO surface (ZnO–NH2 NCs). Thus, the role of both ZnO NC concentration and surface chemistry were tested in terms of biocompatibility towards pre-osteoblast cells, promotion of cell proliferation and differentiation, and also in terms of antimicrobial activity against Gram positive and negative bacteria, such as Escherichia coli and Staphylococcus aureus, respectively. The results suggest that ZnO–NH2 NCs is the most promising candidate to solve infectious disease in bone implants and at the same time promote bone tissue proliferation, even at high concentrations. Although further investigations are needed to clarify the mechanism underlying the inhibition of biofilm formation and to investigate the role of the ZnO–NH2 NCs in in vivo assays, we demonstrated that fine and reproducible control over the chemical and structural parameters in ZnO nanomaterials can open up new horizons in the use of functionalized ZnO NCs as a highly biocompatible and osteoinductive nanoantibiotic agent for bone tissue engineering.

Molecular Dynamics Study of the Biodegradation Process of the Biopolymer Poly (LACTIC)/Poly (VINYL) Scaffold for Bone Tissue Engineering

The biomaterial chosen for the design of the scaffold is poly (lactic) acid (PLA), this type of polyester together with poly(glycolic) acid (PGA) and Poly(lactic-co-glycolic) acid (PLGA) are widely used in tissue engineering because of their ability to tailor mechanical properties, degradation kinetics and also because its morphology and shape that can be easily manipulated in order to improve osteoconduction and osteoinduction. It is important to emphasize that this biopolymer can be found as a racemic mixture. In vitro degradation experiments showed that stereochemical composition has an important role on the rate of degradation, concluding that L(+)-PLA degrades much better that D(-)-PLA.The common process of biodegradation of this type of synthetic polymers is hydrolysis of its ester bonds producing lactic acid. Then this product enters the tricarboxylic acid cycle generating water and carbon dioxide which are non-toxic products present in human body. It is important to highlight that the scaffold degradation process should occur at the same rate of new bone tissue proliferation and the scaffold should keep its mechanical functionality during all the procedure. Previous experiments showed that the width of the biopolymer is directly proportional to the rate of hydrolysis. This is because water molecules can spread quicker throw all the scaffold if it has a wide surface instead of a folded one. Another aspect to consider is the molecular weight and the Young module of the material which determines the degree of elasticity of the bone-scaffold system. Here we report the use of molecular dynamics simulation to estimate several of these parameters from the data generated from these simulations. For instance, we address the solvent accessibility of the polymer and how it changes during the degradation process.

External auditory canal osteoma

Osteomas are a slow growing benign neoplasm of unknown etiology very rarely involving the temporal bone. They develop in the external auditory canal on squamous sections, in the mastoid, middle and inner ear. By bone composition they are divided into spongious (osteoma spongiosum) and compact osteomas (osteoma eburnum); by growth direction, into outward-growing (exosteoma) and in inward-growing (endosteoma); into unilateral and bilateral; by size, into small and gigantic; by surface structure, into smooth and multilobular; by number, into solitary and multiple; into symmetrical and asymmetrical. The symptoms of intracanalicular osteomas are the result of auditory canal obstruction. Diagnosis is made based on case history, clinical examination, audiological processing and radiography (temporal bone CT scan), and confirmed by histopathological examination of the bone. In terms of differential diagnosis, they must be distinguished from exostoses, bone tissue proliferation and osteoid osteomata. The progress of the disease is prolonged, as they are slow growing, asymptomatic and benign tumours. Therapy is surgical only. The report presents the case of a 70-year old patient with the osteoma of the right external auditory canal. In our patient, the osteoma arose in the auditory canal, the most frequent localization; it was unilateral, solitary, multilobular and compact. It was discovered accidentally, during otoscopic examination. The clinical diagnosis was confirmed by CT scan of the temporal bone. We applied surgical therapy by retroauricular approach. The removed bone change was about 12 mm high, 13-14 mm deep and about 8 mm wide. Histopathological findings confirmed osteoma. Due to their slow growth, the rate of auditory canal osteomas develop asymptomatically for a long time without the characteristic clinical features. In most cases, they are discovered accidentally during otoscopic or radiographic examination. The method of choice in diagnosis is temporal bone CT scan. Therapy is surgical.

Surface coatings for improvement of bone cell materials and antimicrobial activities of Ti implants

Ti surface was modified to simultaneously improve bone cell materials and antimicrobial activities. Titanium surface was first anodized in sodium fluoride and sulfuric acid electrolytic solution to form titania nanotube on the surface to improve the biocompatibility of the surface. Silver was electrodeposited on the titania nanotube surface at 5 V. Silver added titania nanotube surface was tested for compatibility with bone-cell materials interactions using human osteoblast bone cells. The antibacterial effect was studied using Pseudomonas aeruginosa. Our results show that silver-treated titania nanotube surface may provide antibacterial properties to prevent implants against postoperative infections without interference to the attachment and proliferation of bone tissue on titanium, which is commonly used in dental and orthopedic surgical procedures.

The antiproliferative role of ERG K+ channels in rat osteoblastic cells

We report on the role of K+ currents in the mechanisms regulating the proliferation of UMR 106-01 osteoblastic osteosarcoma cells. Electrophysiological analysis showed that UMR 106-01 cells produce robust K+ currents that can be pharmacologically separated into two major components: a E-4031-susceptible current, I E-4031, and a tetraethylammonium (TEA)-susceptible component, I TEA. Western blot and RT-PCR analysis showed that I E-4031 is produced by ether a go-go (eag)-related channels (ERG). Incubation of the cells with E-4031 enhanced their proliferation by 80%. Application of E-4031 in the bath solution did not induce instantaneous changes in the membrane resting potential or in the level of cytosolic calcium; however, the cells were slightly depolarized and the calcium content was significantly increased upon prolonged incubation with the compound. Taken together these findings indicate that ERG channels can impair cell proliferation. This is a novel finding that underscores new modes of regulation of mitosis by voltage-gated K+ channels and provides an unexpected insight into the current view of the mechanisms governing bone tissue proliferation.