466 research outputs found
Bisphosphonate-related osteonecrosis of the jaws: A report on 30 cases
Aim: To report a series of thirty cases of bisphosphonate-related osteonecrosis of the jaw (BRONJ). Material and Methods: For 30 patients with BRONJ, gender, age, underlying diagnosis, type of bisphos- phonate (BP), administration route and duration, location and stage of osteonecrosis, symptoms and oral health status, radiological findings of the jaws, treatment and outcome, were recorded. Results: Underlying diagnoses in the series (12 male; 18 female; mean age 70.50 \ub1 9.62) were: 12 multiple myeloma, 7 breast cancer, 3 prostate carcinoma, 1 kidney/lung/ bladder/mediastinal cancer, 1 chronic lymphocytic leukemia, 1 osteoporosis, 1 palatal osteosarcoma + osteoporosis, 1 non-Hodgkin\u2019s lymphoma. Forty-seven osteonecrotic lesions were detected; 30 localized in the mandible, 17 in the maxilla; trigger events were tooth extraction in 31 cases (66%), periodontal disease in 4 (8.50%), incongruous dentures in 3 (6.40%), perimplantitis in 1 (2.10%), unknown in 8 (17%). Twenty-nine patients had received treatment using amino bisphosphonates (25 zoledronate, 2 pamidronate, 2 alendronate) and 1 clodronate; the administration route was intravenous in 27 patients, oral in 2 and intramuscular in 1. Mean number of doses to bone exposure for patients was 34.11 for zoledronate, 50.50 for pamidronate, 146 for alendronate, and 500 for clodronate. Among statistical data the only significant finding was that panoramic dental radiography gave no concrete support for diagnosis of ONJ lesions (p 64 0.04). Conclusions: Our case series reflects literature data. We emphasize the insufficient role of panoramic radiography to study osteonecrotic lesions and the role of poor oral hygiene
Severe hypertension in childhood due to prolonged skin application of a mineralocorticoid ointment
We report the case of a 9-year-old boy suffering from exzematous dermatitis who was treated for 6 years with a daily dose of 100 mg of a dermatological ointment containing 9 alpha-fluoroprednisolone-21-acetate. At examination the patient's blood pressure was persistently 230/160 mm Hg and was considered essential in origin after secondary forms of arterial hypertension had been excluded. Treatment with nifedipine and labetalol lowered the blood pressure to 150/100 mm Hg. When we became aware of the dermatological treatment, we advised its discontinuance. In the subsequent 7 days, the blood pressure fell to hypotensive levels (75/40 mm Hg) and then became normal a few days after discontinuance of the antihypertensive therapy. This case suggests that prolonged use of topical steroids, commonly prescribed for skin diseases, may cause hypertension, especially in childhood
Cytocompatible and anti-bacterial adhesion nanotextured titanium oxide layer on titanium surfaces for dental and orthopedic implants
Electron beam structuring of Ti6Al4V: New insights on the metal surface properties influencing the bacterial adhesion
Soft tissue adhesion and infection prevention are currently challenging for dental transmucosal or percutaneous orthopedic implants. It has previously been shown that aligned micro-grooves obtained by Electron Beam (EB) can drive fibroblast alignment for improved soft tissue adhesion. In this work, evidence is presented that the same technique can also be effective for a reduction of the infection risk. Grooves 10-30 \u3bcm wide and around 0.2 \u3bcm deep were obtained on Ti6Al4V by EB. EB treatment changes the crystalline structure and microstructure in a surface layer that is thicker than the groove depth. Unexpectedly, a significant bacterial reduction was observed. The surfaces were characterized by field emission scanning electron microscopy, X-ray diffraction, confocal microscopy, contact profilometry, wettability and bacterial adhesion tests. The influence of surface topography, microstructure and crystallography on bacterial adhesion was systematically investigated: it was evidenced that the bacterial reduction after EB surface treatment is not correlated with the grooves, but with the microstructure induced by the EB treatment, with a significant bacterial reduction when the surface microstructure has a high density of grain boundaries. This correlation between microstructure and bacterial adhesion was reported for the first time for Ti alloys
Generation of cytocompatible superhydrophobic Zr–Cu–Ag metallic glass coatings with antifouling properties for medical textiles
Zirconium–Copper-based metallic glass thin films represent promising coatings in the biomedical sector for their combination of antibacterial property and wear resistance. However, finding a Zr–Cu metallic glass composition with desirable cytocompatibility and antibacterial property is extremely challenging. In this work, we have created a cytocompatible and (super-)hydrophobic Zr–Cu–Ag metallic glass coating with ≈95% antifouling properties. First, a range of different chemical compositions were prepared via Physical Vapor Deposition magnetron by co-sputtering Zr, Cu, and Ag onto a Polybutylene terephthalate (PBT) substrate among which Zr93·5Cu6·2Ag0.2, Zr76·7Cu22·7Ag0.5, and Zr69·3Cu30·1Ag0.6 were selected to be further investigate for their surface properties, antibacterial activity, and cytocompatibility. Scanning electron microscopy (SEM) images revealed a micro-roughness fibrous structure holding superhydrophobic properties demonstrated by specimens' static and dynamic contact angle measurements ranging from 130° to 150°. The dynamic contact angle measurements have shown hysteresis below 10° for all coated samples which indicated the superhydrophobicity of the samples. To distinguish between antifouling and bactericidal effect of the coating, ions release from coatings into Luria Bertani Broth (LB), and Dulbecco's Modified Eagle Medium (DMEM) solutions were evaluated by inductively coupled plasma mass spectrometry (ICP-MS) measurements after 24 ​h and 5 days. Antifouling properties were evaluated by infecting the specimens' surface with the Gram-positive Staphylococcus aureus and the Gram-negative Escherichia coli strain reporting a ≈95% reduction of bacteria adhesion as visually confirmed by FESEM and fluorescent live/dead staining. Human mesenchymal stem cells (hMSC) were used for direct cytocompatibility evaluation of coated samples and their metabolic activity was evaluated via relative fluorescence unit after 24 ​h and 5 days confirming that it was comparable to the controls (>97% viable cells). The results were further visualized by FESEM, fluorescent staining by Live/Dead Viability/Cytotoxicity Kit and confirmed the cytocompatibility of all coated samples. Finally, hMSC′ cytoplasm was stained by May Grunwald and Giemsa after 5days to detect and visualize the released ions which have diffused through the cells' membrane
Cell Penetrating Peptide Adsorption on Magnetite and Silica Surfaces: A Computational Investigation
Magnetic nanoparticles (MNPs) represent one of the most promising materials as they can act as a versatile platform in the field of bionanotechnology for enhanced imaging, diagnosis, and treatment of various diseases. Silica is the most common compound for preparing coated iron oxide NPs since it improves colloidal stability and the binding affinity for various organic molecules. Biomolecules such as cell penetrating peptides (CPPs) might be employed to decorate MNPs, combining their promising physicochemical properties with a cell penetrating ability. In this work, a computational investigation on adsorption of Antennapedia homeodomain-derived penetrating peptide (pAntp) on silica and magnetite (MAG) surfaces is presented. By employing umbrella sampling molecular dynamics, we provided a quantitative estimation of the pAntp-surface adsorption free energy to highlight the influence of surface hydroxylation state on the adsorption mechanism. The interaction between peptide and surface has shown to be mainly driven by electrostatics. In case of MAG surface, also an important contribution of van der Waals (VdW) attraction was observed. Our data suggest that a competitive mechanism between MNPs and cell membrane might partially inhibit the CPP to carry out its membrane penetrating function
Biological evaluation of a new sodium-potassium silico-phosphate glass for bone regeneration: In vitro and in vivo studies
In vitro and in vivo studies are fundamental steps in the characterization of new im-plantable materials to preliminarily assess their biological response. The present study reports the in vitro and in vivo characterizations of a novel experimental silicate bioactive glass (BG) (47.5 B, 47.5 SiO2-10 Na2O-10 K2O-10 MgO-20 CaO-2.5 P2O5 mol.%). Cytocompatibility tests were perfor-med using human mature osteoblasts (U2OS), human mesenchymal stem cells (hMSCs) and human endothelial cells (EA.hy926). The release of the early osteogenic alkaline phosphatase (ALP) marker suggested strong pro-osteogenic properties, as the amount was comparable between hMSCs cultivated onto BG surface and cells cultivated onto polystyrene control. Similarly, real-time PCR revealed that the osteogenic collagen I gene was overexpressed in cells cultivated onto BG surface without biochemical induction. Acute toxicity tests for the determination of the median lethal dose (LD50 ) al-lowed classifying the analyzed material as a slightly toxic substance with LD50 = 4522 ± 248 mg/kg. A statistically significant difference in bone formation was observed in vivo through comparing the control (untreated) group and the experimental one, proving a clear osteogenic effect induced by the implantation at the defect site. Complete resorption of 47.5 B powder was observed after only 3 months in favor of newly formed tissue, thus confirming the high osteostimulatory potential of 47.5 B glass
Surface Properties and Antioxidant Activity of Silicate and Borosilicate Bioactive Glasses
Herein, silicate and borosilicate bioactive glasses are synthetized and characterized. The antioxidant activity, in the presence and absence of human osteoblasts' progenitor cells, of the different glass compositions, is correlated to the surface properties: wettability, zeta potential, hydroxylation degree, reactivity in simulated body fluid (SBF), and Tris buffer. An enhancing effect of boron in glass reactivity and a stabilizing role of Sr and Mg are evidenced. The scavenging potential of the analyzed bioactive glasses toward reactive oxygen species (ROS) is clearly proved. Moreover, cellular tests confirm the protective effect of the bioactive glasses toward viable cells acting as ROS/RNS species scavenger. The obtained results represent an original improvement of the knowledge concerning the intrinsic antioxidant ability of bioactive glasses with different compositions and the mechanisms involved
Electrophoretic deposition of composite coatings based on alginate matrix/45S5 bioactive glass particles doped with B, Zn or Sr
In this research work composite coatings made of alginate and 45S5 bioactive glass particles doped with B, Zn or Sr were synthesized by means of electrophoretic deposition and characterized from morphological, compositional, thermogravimetric, mechanical and electrochemical points of view. The developed coatings were also subjected to in vitro test in SBF solution to evaluate their ability to induce hydroxyapatite precipitation and cytocompatibility evaluation using human primary fibroblasts. The obtained results demonstrated a good homogeneity of the coatings, high adhesion and a protective behavior towards the substrate. The thermogravimetric analysis proved that the glass amount was constant before and after the deposition and all the investigated coatings promoted the deposition of hydroxyapatite but with different kinetics. Since the Zn containing coating showed the best bioactive behavior it was subjected to cytocompatibility test, which demonstrated, after an initial reduction of cell viability, a good cell proliferation and the production of collagen from the ECM. These findings suggest that the obtained coatings are promising materials to coat metallic prosthetic devices
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