Gluing Living Bone Using a Biomimetic Bioadhesive: From Initial Cut to Final Healing

Osteoporotic fractures are a growing issue due to the increasing incidence of osteoporosis worldwide. High reoperation rates in osteoporotic fractures call for investigation into new methods in improving fixation of osteoporotic bones. In the present study, the strength of a recently developed bone bioadhesive, OsStictm, was evaluated in vivo using a novel bone core assay in a murine animal model at 0, 3, 7, 14, 28, and 42 days. Histology and micro-CT were obtained at all time points, and the mean peak pull-out force was assessed on days 0–28. The adhesive provided immediate fixation to the bone core. The mean peak bone core pull-out force gradually decreased from 6.09 N (σ 1.77 N) at day 0 to a minimum of 3.09 N (σ 1.08 N) at day 7, recovering to 6.37 N (σ 4.18 N) by day 28. The corresponding fibrin (Tisseel) control mean peak bone core pull-out characteristic was 0.27 N (σ 0.27 N) at day 0, with an abrupt increase from 0.37 N (σ 0.28) at day 3, 6.39 N (σ 5.09 N) at day 7, and continuing to increase to 11.34 N (σ 6.5 N) by day 28. The bone cores failed either through core pull-out or by the cancellous part of the core fracturing. Overall, the adhesive does not interrupt healing with pathological changes or rapid resorption. Initially, the adhesive bonded the bone core to the femur, and over time, the adhesive was replaced by a vascularised bone of equivalent quality and quantity to the original bone. At the 42 day time point, 70% of the adhesive in the cancellous compartment and 50% in the cortical compartment had been replaced. The adhesive outwith the bone shell was metabolized by cells that are only removing the material excess with no ectopic bone formation. It is concluded that the adhesive is not a physical and biochemical barrier as the bone heals through the adhesive and is replaced by a normal bone tissue. This adhesive composition meets many of the clinical unmet needs expressed in the literature, and may, after further preclinical assessments, have potential in the repair of bone and osteochondral fragments.

Ossifying Fibroma of the Maxilla: A Case Report and Literature Update

Ossifying fibroma is a rare benign fibro-osseous neoplasm of the jaw characterized by the replacement of normal bone tissue by a combination of fibrous tissue and newly formed calcified tissues of bone and/or cementum-like material. Lesions often manifest at the 2nd to 4th decades of life with a predominant female predilection. The tumor is usually slow-growing and asymptomatic but can cause notable expansion of the jawbones. Definitive diagnosis of OF can be challenging and usually requires careful clinical, radiographic and histologic assessments. Treatment commonly depends on the size, location and aggressiveness of tumor and can accordingly vary from enucleation and curettage to resection and bone grafting. The prognosis is generally good when the lesion is completely removed, but recurrence is possible in some circumstances. The aim of this article is to present a case report of a recurrent ossifying fibroma in a 28-year-old female patient and to provide an update of the literature.

Spinal Arachnoiditis Ossificans: A Case-Based Update

Arachnoiditis ossificans is a rare disease, characterized by intradural ossifications, representing the end stage of chronic adhesive arachnoiditis. We describe the case of a 55-year-old patient who developed symptoms of a cauda equina syndrome after an open microdiscectomy at the L5 to S1 segment. A subsequent exploratory surgery revealed an intradural concentric bony structure with partly incorporated and partly adherent nerve roots. A partial removal of the intradural calcifications was performed. Postoperatively, the patient showed neurological improvement. The removed intradural calcifications were submitted for histological analysis and proved to be normal bone tissue, notably containing yellow bone marrow. To our knowledge, the presence of yellow bone marrow within bony cavities of arachnoiditis ossificans has not previously been reported.

Finite memory model of bone healing in analysis of moving interface between mandible tissue and bone substitute material after tooth implant application

A previous bone remodelling model was presented elsewhere [30], and in the present paper, the same model was tested with new conditions; an interaction between bone tissue, bone substitute material and a dental implant was considered. The bone substitute material was assumed to be dead tissue, which does not synthesizes neither absorbs bone tissue, and it was considered, as well, resolvable. A moving border between the bone substitute material and the bone tissue was studied. The border moved as the newly synthesised bone tissue took over the bone substitute material. After the numerical calculations of time-steps, the whole bone substitute material was replaced by normal bone tissue and the implant was fixed in place only by bone tissue. Dynamical studies of the interaction of bone tissue and implant are used to improved implant design considering different factors, in this case, the presence of bone substitute material helping to fix the implant.

Mandibular Reconstruction with Autogenous Graft After Surgical Treatment of Cemento-Ossifying Fibroma: a Case Report and Literature Review

Fibro-bone lesions (LFO) are defined as a group of lesions characterized by the replacement of normal bone tissue with fibrous connective tissue, of variable cellularity, permeated by a variable amount of mineralized material, whose microscopic appearance may resemble bone, cement or a mixture of both. Among the injuries that make up this group, we can mention: fibrous dysplasia, ossifying fibroma, bone dysplasia and cemento-bone dysplasia. In this case report, we presented a mandibular reconstruction with free autogenous graft from the iliac crest, with the use of stereolithography prototyping, after the surgical treatment of a cemento-ossifying fibroma, as well as to describe the clinical, epidemiological, radiographic characteristics, and histological, the differential diagnosis and the form of treatment of the referred pathology.

Expression of MiR-664-3p in Osteosarcoma and Its Effects on the Proliferation and Apoptosis of Osteosarcoma Cells

Background: To explore the expression level of miR-664-3p in osteosarcoma and its effects on the proliferation and apoptosis of osteosarcoma cells. Methods: Specimens of osteosarcoma tissues were collected from 41 cases undergoing surgical treatment in the Orthopedics Department of Wuhan Puai Hospital, Wuhan, China from January 2015 to February 2018. Another 40 cases of normal bone tissue were collected. The expression of miR-664-3p were detected using quantificational real-time polymerase chain reaction. miR-664-3p mimics, miR-664-3p inhibitor and miR-664- 3p negative control (NC) were used to transfect U2-OS, which were named as mimics group, inhibitor group and NC group, respectively. MTT assay was adopted to detect the effects of microRNA-664-3p on the proliferation of U2-OS after 24, 48, 72, 96 and 120 hours of transfection. Flow cytometry was applied to measure the apoptosis rate of U2-OS after miR-664-3p transfection. Finally, Western Blot was employed to detect the expression of proteolipid protein 2 (PLP2). Results: The total apoptosis rate of cells in the inhibitor group was obviously higher than those in the mimics group and the NC group (P<0.001). The relative expression level of PLP2 in the inhibitor group was significantly lower than those in the mimics group and the NC group (P<0.001). Conclusion: MiR-664-3p may be involved in the occurrence and development of osteosarcoma, and can regulate the proliferation and apoptosis of U2-OS cells, and the expression of PLP2. Besides, miR-664-3p may become a novel molecular biological indicator for the diagnosis, targeted treatment and prognosis assessment of osteosarcoma.

Testosterone replacement therapy in male urolithiasis patients with metabolic syndrome

Urolithiasis is one of the most wide-spread kidney lesions in males and females all over the world. It is particularly important for males with hypogonadism and metabolic syndrome. The goal of the study is to assess the effectiveness and safety of Testosterone replacement therapy in males with hypogonadism and metabolic syndrome. Patients and methods. 465 male urolithiasis patients were studied. Mean age was 46 (38-54 years). All patients involved in the study had excessive body mass and obesity of various extent. Mean body mass was 92 (85-97 kg) and body mass index 40.5. More than 50% of the patients had Ischaemic Heart Disease, Cholelithiasis and Goiter. Essential Hypertension was present in 76.3% of cases. In more than 50% of the cases there was a combination of two or three nosological forms present. Depending on the replacement therapy used all patients were distributed into two groups: the main (300 patients) and the control one (165 patients). Results of the study. Testosterone replacement therapy proved to contribute to normalization of mineral and lipid metabolism as well as improvement of kidney function and restoration of normal bone tissue density. Analysis of 5-year relapse frequency demonstrated it to be considerably lower in the main group (10%) than in the control one (30%) which is astatistically valid difference (p < 0.05). Conclusion. Testosterone replacement therapy is a highly effective and safe method for urolithiasis therapy in males with hypogonadism.

Vascular calcification

Vascular calcification (VC) is a common feature of patients with advanced CKD and it could be, at least in part, the cause of increased cardiovascular mortality in these patients. From a morphologic point of view, there are at least two types of pathologic calcium phosphate deposition in the arterial wall—namely, intima calcification (mostly associated with atherosclerotic plaques) and media calcification (associated with stiffening of the vasculature, resulting in significantly adverse cardiovascular outcomes). Although VC was viewed initially as a passive phenomenon, it appears to be a cell-mediated, dynamic, and actively regulated process that closely resembles the formation of normal bone tissue, as discovered recently. VC seems to be the result of the dysregulation of the equilibrium between promoters and inhibitors. The determinants are mostly represented by altered calcium and phosphorus metabolism, secondary hyperparathyroidism, vitamin D excess, high fibroblast growth factor 23, and high levels of indoxyl sulphate or leptin; meanwhile, the inhibitors are vitamin K, fetuin A, matrix G1a protein, osteoprotegerin, and pyrophosphate. A number of non-invasive imaging techniques are available to investigate cardiac and vascular calcification: plain X-rays, to identify macroscopic calcifications of the aorta and peripheral arteries; two-dimensional ultrasound for investigating the calcification of carotid arteries, femoral arteries, and aorta; echocardiography, for assessment of valvular calcification; and, of course, computed tomography technologies, which constitute the gold standard for quantification of coronary artery and aorta calcification. All these methods have a series of advantages and limitations. The treatment/ prevention of VC is currently mostly around calcium-mineral bone disease interventions, and unproven. There are interesting hypotheses around vitamin K, Magnesium, sodium thiosulphate and other potential agents.

miR-194 Suppresses Proliferation and Migration and Promotes Apoptosis of Osteosarcoma Cells by Targeting CDH2

Background/Aims: Studies have shown that miR-194 functions as a tumour suppressor and is associated with tumour growth and metastasis. This study intends to uncover the mechanism of tumour suppression by miR-194. The expression of miR-194 in osteosarcoma cell lines and tissues were monitored by real-time PCR. Methods: The proliferation ability was examined by MTT assay. Migration and apoptosis of cells were monitored by migration assay and flow cytometry, respectively. The regulation of miR-194 on CDH2 was determined by luciferase assays and western blot assays. Results: The results showed that miR-194 was significantly reduced in osteosarcoma compared with that in normal bone tissue. Overexpression of miR-194 significantly attenuated the proliferation and migration and induced the apoptosis of osteosarcoma cells. Furthermore, we demonstrated that miR-194 has inhibited the malignant behaviour of osteosarcoma by downregulating CDH2 expression. Conclusions: These findings suggested that miR-194 may act as a tumour suppressor in osteosarcoma. miR-194/CDH2 may be a novel therapeutic target in the treatment of osteosarcoma.

Osseous Choristoma of the Tongue: A Review of Etiopathogenesis

Osseous choristoma is a normal bone tissue in an ectopic position. In the oral region lingual localization occurs more frequently and the mass is generally localized on the dorsum of the tongue. Definitive diagnosis is obtained only after histopathologic examination. The etiology remains already debatable. The treatment of choice is surgical excision. In this paper we present a case of tongue osseous choristoma and a review of the literature.