Search results for " Bone"
showing 10 items of 933 documents
Bone Scaffolds Based on Degradable Vaterite/PEG‐Composite Microgels
2019
Vaterite, a metastable modification of calcium carbonate, embedded in a flexible microgel packaging with adjustable mechanical properties, functionality, and biocompatibility, provides a powerful scaffolding for bone tissue regeneration, as it is easily convertible to bone-like hydroxyapatite (HA). In this study, the synthesis and physical analysis of a packaging material to encapsulate vaterite particles and osteoblast cells into monodisperse, sub-millimeter-sized microgels, is described whereby a systematic approach is used to tailor the microgel properties. The size and shape of the microgels is controlled via droplet-based microfluidics. Key requirements for the polymer system, such as …
Towards the development of a fossil bone geochemical standard: An inter-laboratory study
2007
Ten international laboratories participated in an inter-laboratory comparison of a fossil bone composite with the objective of producing a matrix and structure-matched reference material for studies of the bio-mineralization of ancient fossil bone. We report the major and trace element compositions of the fossil bone composite, using in-situ method as well as various wet chemical digestion techniques. For major element concentrations, the intra-laboratory analytical precision (%RSDr) ranges from 7 to 18%, with higher percentages for Ti and K. The %RSDr are smaller than the inter-laboratory analytical precision (%RSDR; 100% was found for the high field strength elements (Hf, Th, Zr, Nb). The…
PathVisio Analysis: An Application Targeting the miRNA Network Associated with the p53 Signaling Pathway in Osteosarcoma
2021
MicroRNAs (miRNAs) are small single-stranded, non-coding RNA molecules involved in the pathogenesis and progression of cancer, including osteosarcoma. We aimed to clarify the pathways involving miRNAs using new bioinformatics tools. We applied WikiPathways and PathVisio, two open-source platforms, to analyze miRNAs in osteosarcoma using miRTar and ONCO.IO as integration tools. We found 1298 records of osteosarcoma papers associated with the word "miRNA". In osteosarcoma patients with good response to chemotherapy, miR-92a, miR- 99b, miR-193a-5p, and miR-422a expression is increased, while miR-132 is decreased. All identified miRNAs seem to be centered on the TP53 network. This is the first …
Improved Bone Regeneration Using Biodegradable Polybutylene Succinate Artificial Scaffold in a Rabbit Model
2022
The treatment of extensive bone loss represents a great challenge for orthopaedic and reconstructive surgery. Most of the time, those treatments consist of multiple-stage surgeries over a prolonged period, pose significant infectious risks and carry the possibility of rejection. In this study, we investigated if the use of a polybutylene succinate (PBS) micro-fibrillar scaffold may improve bone regeneration in these procedures. In an in vivo rabbit model, the healing of two calvarial bone defects was studied. One defect was left to heal spontaneously while the other was treated with a PBS scaffold. Computed tomography (CT) scans, histological and immunohistochemical analyses were performed …
Maxillary bone necrosis following the use of bisphosphonates in patients with cancer: management and case series
2008
Bisphosphonates are bone-turnover modulating drugs used to treat various diseases such as certain cancers, bone metastasis, bone- and calcium-related disorders, Paget`s disease, osteoporosis and osteopenia. Recently, several preliminary reports have reported the insurgence of osteonecrosis of the mandible and/or maxilla, associated with intravenously administered bisphosphonates. This case series describes the effects of bisphosphonates used in the treatment of certain cancers on oral bone tissues.
Specific expression of a TRIM-containing factor in ectoderm cells affects the skeletal morphogenetic program of the sea urchin embryo
2011
In the indirect developing sea urchin embryo, the primary mesenchyme cells (PMCs) acquire most of the positional and temporal information from the overlying ectoderm for skeletal initiation and growth. In this study, we characterize the function of the novel gene strim1, which encodes a tripartite motif-containing (TRIM) protein, that adds to the list of genes constituting the epithelial-mesenchymal signaling network. We report that strim1 is expressed in ectoderm regions adjacent to the bilateral clusters of PMCs and that its misexpression leads to severe skeletal abnormalities. Reciprocally, knock down of strim1 function abrogates PMC positioning and blocks skeletogenesis. Blastomere tran…
Association between periodontal disease and non-fatal ischemic stroke: a case-control study
2014
This study aimed to investigate the association between clinical and radiological markers of periodontal disease and ischemic stroke and to assess the potential influence of inflammatory response on the observed associations.A prospective case-control study including a series of 48 cases with a minor ischemic stroke and 47 controls was conducted at the University Hospital of Dijon. Vascular risk factors, clinical dental examination (plaque index, gingival index, percentage of pockets5 mm, percentage of bleeding on probing (BOP) sites), dental panoramic (bone loss) and biological parameters (CRP, total cholesterol, HDL, LDL, fasting glucose) were collected. Conditional regression analyses we…
Bone status in adolescents with type 1 diabetes
2010
Aims The aim of the study was to investigate the potential negative impact of type 1 diabetes on bone status of adolescents. Bone status in adolescents with type 1 diabetes was assessed by means of quantitative ultrasound (QUS) and the influence of metabolic control and other diseaserelated and growth variables was analysed. Methods Group I consisted of 99 pubertal (Tanner ≥2) adolescents (49 female), aged 14.3±2.5 years, diabetes duration 4.6±2.3 years. Controls (group II) were 297 children, matched by sex and age, from a healthy population. The influence of glycated haemoglobin (current: HbA1cD; last year’s mean: HbA1cY; whole duration mean: HbA1cT), diabetes duration, percentage of life …
Haemopoietic effects of 7 alpha, 17 beta dimethyltestosterone.
1979
Some haematic parameters were investigated in female COBS mice treated with 7 alpha, 17 beta Dimethyltestcsterone (DMT). The drug causes an increase of circulating platelets in normal mice. Bone marrow graft from DMT-treated donors facilitates in irradiated mice repopulation of white blood cells and platelets but lowers % survival. These data are interpreted on the basis of a commitment and a loss of self-maintenance induced by DMT on CFUs compartment. © 1979 The Italian Pharmacological Society.
Alternative method to treat oroantral communication and fistula with autogenous bone graft and platelet rich firbin
2016
Background Removing a tooth from the jaw results in the occurrence of oroantral communication in beneficial anatomic conditions or in the case of a iatrogenic effect. Popularized treatments of the oroantral communication have numerous faults. Large bone defect eliminates the chance to introduce an implant. Purpose of this work was assessment of the usefulness of autogenous bone graft and PRF in normal bone regeneration in the site of oroantral communication. Material and Methods Bone regeneration in the site of oroantral communication was assessed in 20 patients. Bone defects were supplemented autogenous bone graft from mental protuberance in 14 cases and from oblique line in 6 cases. The g…