The radioprotection management of a PET department with a cyclotron and radiopharmacy laboratory, in accordance with Italian legislation

The possibility of setting up a positron emission tomography (PET) facility with a cyclotron and radiopharmaceutical laboratory in situ, at a feasible price and in a very restricted space, has led to a steady increase both in the use of the PET technique in diagnostic clinical routine imaging and in the number of cyclotrons for drug production. Owing to the progress made in the PET procedures, it is now possible to have not only a highly innovative system of diagnostic examination, with a remarkable improvement in the diagnostic quality and patient care, but also a considerable increase in the number of daily examinations. In this paper, the authors show how the acquired know-how, with respect to radioprotection, has applied to the planning, running and management of the PET/CT unit, installed in the Imaging Diagnostic Department of the Policlinico Tor Vergata (PTV), at Tor Vergata University, Rome.     

Degradable phosphate glass fiber reinforced polymer matrices: mechanical properties and cell response

The development of biodegradable materials for internal fracture fixation is of great interest, as they would both eliminate the problem of stress shielding and obviate the need for a second operation to remove fixation devices. Preliminary investigations for the production of degradable fiber reinforced polymer composite materials are detailed. Composites were produced of phosphate invert glass fibers of the glass system P₂O₅–CaO–MgO–Na₂O–TiO₂, which showed a low solubility in previous work. The fibers were embedded into a matrix of a degradable organic polymer network based on methacrylate-modified oligolactide. Fracture behavior, bending strength and elastic modulus were evaluated during 3-point bending tests and the fracture surface of the composites was investigated using a scanning electron microscope. Short-term biocompatibility was tested in an FDA/EtBr viability assay using MC3T3-E1 murine pre-osteoblast cells and showed a good cell compatibility of the composite materials. Results suggested that these composite materials are biocompatible and show mechanical properties which are of interest for the production of degradable bone fixation devices.     

Cannabinoids Drugs and Oral Health—From Recreational Side-Effects to Medicinal Purposes: A Systematic Review

Background: marijuana, the common name for cannabis sativa preparations, is one of the most consumed drug all over the world, both at therapeutical and recreational levels. With the legalization of medical uses of cannabis in many countries, and even its recreational use in most of these, the prevalence of marijuana use has markedly risen over the last decade. At the same time, there is also a higher prevalence in the health concerns related to cannabis use and abuse. Thus, it is mandatory for oral healthcare operators to know and deal with the consequences and effects of cannabis use on oral cavity health. This review will briefly summarize the components of cannabis and the endocannabinoid system, as well as the cellular and molecular mechanisms of biological cannabis action in human cells and biologic activities on tissues. We will also look into oropharyngeal tissue expression of cannabinoid receptors, together with a putative association of cannabis to several oral diseases. Therefore, this review will elaborate the basic biology and physiology of cannabinoids in human oral tissues with the aim of providing a better comprehension of the effects of its use and abuse on oral health, in order to include cannabinoid usage into dental patient health records as well as good medicinal practice. Methods: the paper selection was performed by PubMed/Medline and EMBASE electronic databases, and reported according to the PRISMA guidelines. The scientific products were included for qualitative analysis. Results: the paper search screened a total of 276 papers. After the initial screening and the eligibility assessment, a total of 32 articles were considered for the qualitative analysis. Conclusions: today, cannabis consumption has been correlated to a higher risk of gingival and periodontal disease, oral infection and cancer of the oral cavity, while the physico-chemical activity has not been completely clarified. Further investigations are necessary to evaluate a therapeutic efficacy of this class of drugs for the promising treatment of several different diseases of the salivary glands and oral diseases.     

Use of annatto dye extraction residue as additive in the cassava starch composite foam tray

Pigment extraction from annatto seed results in large amounts of by-products (~97%) and residual carotenoid content. In this work, composite foam trays containing 90:10 (10AR), 80:20 (20AR), and 70:30 (30AR) cassava starch: annatto residue (AR) ratios were prepared by thermopressing. The physical–chemical properties, thermal stability, antioxidant activity, and biodegradability of the composite foam trays and cassava starch foam tray (control) were measured and compared. High AR ratio (20AR and 30AR) yielded thicker (2.1–2.3 mm), denser (0.72–0.74 g/cm³), and less porous (32.5–33%) composite foam trays than the control due to incomplete cassava starch gelatinization and the presence of fibers, lipids, and proteins in AR. Thus, the composite foam trays had lower mechanical resistance (0.4–0.8 MPa) and elongation (0.4%–0.7%) than the control (2.9 MPa and 1.5%). However, addition of high AR ratio increased the foam tray resistance to water and yielded colorful foam trays with antioxidant property as measured by DPPH^• (0.11 to 0.52 μM TE/100 g) and ABTS^•+ (7.86–53.77 μM TE/100 g). Increasing the AR ratio in the composite foam tray delayed the biodegradation time by 17 days as compared to the control, but all the foam trays were more biodegradable than EPS. Therefore, AR has potential use in the production of bioactive composite foam trays.     

Limitations on the sintering of graded particle systems

Improvement of compact density is commonly achieved by blending coarse and fine particles, but these compacts will not densify without the presence of a significant amount of liquid phase. It was proposed that two step sintering (TSS) could be applied to sinter the fine particle matrix, potentially accommodating the presence of inclusions of large particles. This hypothesis was false. Compacts were prepared with similar green density but with different ratios of coarse, medium, and fine particles and then subjected to TSS. The results indicated that constrained sintering limits densification on both ends of the particle packing spectrum: A fine particle matrix containing large particles fails to densify because the matrix cannot shrink around the inclusion; the densification of fine particle pockets in a skeletal network composed of large particles does not allow sufficient shrinkage in the pockets of small particles.     

Surface area reduction during the sintering of alumina

Surface area reduction trajectories of two well characterized calcined alumina powders were analyzed over a range of thermal profiles. Surface area reduction trajectories were confirmed to be independent of initial green density. Variations in trajectory were explained through experimental demonstrations of blended coarse and fine particle alumina systems. This work demonstrates that (1) nanoparticles do not appear to assist conventional sintering, because the nanoparticle surface area drops precipitously with minimal increase in density; and (2) the initial compact density does not contribute, nor control, surface area reduction during alumina sintering.     

Physical–chemical,thermal, and functional properties of achira (Canna indica L.) flour and starch from different geographical origin

Achira (Canna indica L.) is a plant native to the Andes in South America, a starchy source, and its cultivation has expanded to different tropical countries, like Brazil. In order to evaluate the potential of this species, starch and flours with different particle size were obtained from Brazilian achira rhizomes. Proximal analyses, size distribution, SEM, swelling power, solubility, DSC, XRD analysis, and FTIR were performed for characterization of these materials. Flours showed high dietary fiber content (16.5–32.2% db) and high concentration of starch in the case of the smaller particle size fraction. Significant differences in protein and starch content, swelling power, solubility, and thermal properties were observed between the Brazilian and the Colombian starch. All the studied materials displayed the B‐type XRD pattern with relative crystallinity of 20.1% for the flour and between 27.0 and 28.0% for the starches. Results showed that the starch and flour produced from achira rhizomes have great technological potential for use as functional ingredient in the food industry.