[en] To examine factors which affect local recurrence of osteoid osteomas treated with percutaneous CT-guided radiofrequency thermocoagulation. A prospective study was carried out on 45 patients with osteoid osteoma who underwent percutaneous radiofrequency thermocoagulation with a minimum follow-up of 12 months There were seven local recurrences (16%); all occurred within the first year. Local recurrence was significantly related to a non-diaphyseal location (P<0.01). There was no significant relationship (P=0.05) between local recurrence and age of the patient, duration of symptoms, previous treatment, size of the lesion, positive biopsy, radiofrequency generator used or the number of needle positions. There were no complications. Osteoid osteomas in a non-diaphyseal location are statistically more likely to recur than those in a diaphyseal location when treated with CT-guided percutaneous radiofrequency thermocoagulation. This relationship between local recurrence and location has not been previously reported. (orig.)

[en] Although the rare complication of squamous cell carcinoma in chronic osteomyelitis is well known, benign squamous epithelial proliferation can also occur, causing osteolysis and fracture. The radiological and correlated pathological features of osteolysis from this benign complication of chronic osteomyelitis are presented

[en] The adsorption behaviour of mesoporous SBA-15 and its plugged analogues (PHTS) were studied in detail. The SBA-15 materials consist of a 2-D hexagonally ordered array of long interconnected pore channels with diameters, which can vary within the range of 4.6 to 30 nm. The PHTS is an analogous materials to SBA-15 containing extra microporous amorphous silica nanoparticles (plugs) within the mesopores thus creating a material with superior mechanical stability. For both types of materials, the adsorption characteristics were evaluated using linear (n-hexane and n-heptane), branched (3-methylpentane), cyclic (c-hexane) and unsaturated (1-hexene) hydrocarbons. For n-hexane, c-hexane, 3-methylpentane and n-heptane the adsorption is mainly controlled by steric effects (size and shape of the molecules), structure of the adsorbed layer and the presence and location of plugs inside the mesoporous channel system. However, the sorption of unsaturated hydrocarbons is additionally governed by the hydrophobic/hydrophilic properties of the adsorbent. Furthermore, the effect of the surface topology in SBA and PHTS on the deposition of transition metal oxides, using the molecular designed dispersion (MDD) technique, was studied by the adsorption behaviour of VO (acac)2 and dimeric TiO(acac)2. In contrast to the SBA-15, the sorption in PHTS materials was mainly controlled by the size of the adsorbate and the sorption temperature. (authors)

[en] To predict accurately whether a soft tissue mass was benign or malignant and to characterize its type using ultrasound, shear wave elastography and MRI. We hypothesized that with the addition of shear wave elastography, it would be possible to determine a threshold velocity value to classify a lesion as benign or malignant. A total of 151 consecutive, consenting adult patients were prospectively recruited to this study in a tertiary referral musculoskeletal oncology centre. All lesions were assessed with ultrasound, including B mode, Doppler and shear wave elastography measurements. One hundred thirty-eight patients also underwent MRI of the lesion. A histological diagnosis was obtained for all lesions. Malignant lesions were larger than benign lesions and had a greater Doppler activity. There was no useful threshold shear wave velocity to differentiate between benign and malignant lesions. Longitudinal and transverse shear wave velocities were strongly positively correlated with each other. An inverse correlation was shown with lesion size and depth, regardless of whether it was benign or malignant. A logistic regression model combining the ultrasound and MRI characteristics did not confidently classify a lesion as benign or malignant and was inferior to expert opinion. The strongest predictors of malignancy are large lesion size and high vascularity. The combination of all ultrasound characteristics (including shear wave elastography) and MRI features does not confidently classify a lesion as benign or malignant, and histological diagnosis remains the gold standard.

[en] With the evolution of the field of nanomaterials in the past number of years, it has become apparent that it will be key to future technological developments. However, while there are unlimited research undertakings on nanomaterials, limited research results on nanomaterial costs exist; all in spite of the generous funding that nanotechnology projects have received. There has recently been an exponential increase in the number of studies concerning health-related nanomaterials, considering the various medical applications of nanomaterials that drive medical innovation. This work aims to analyze the effect of the cost factor on acceptability of health-related nanomaterials independently or in relation to material toxicity. It appears that, from the materials studied, those used for cancer treatment applications are more expensive than the ones for drug delivery. The ability to evaluate cost implications improves the ability to undertake research mapping and develop opinions on nanomaterials that can drive innovation.

[en] Over the past 30 years, there have been significant advancements in the field of nanomaterials. The possibility to use them in applications such as cancer treatment is extremely promising; however, the toxicity of many nanomaterials as well as the high costs associated with their use is still a concern. This paper aims to study the connection between nanomaterial toxicity and cost. This synergy may be interpreted as a different version of the classic “Prisoner's Dilemma” game, which in this case attempts to explain the possible outcomes of cooperation versus conflict between science advocating for the use of high-risk, possibly toxic materials due to their high returns, and society that might be dubious about the use of high-risk materials. In an effort to create diverse evaluation methodologies, this work uses a forecast horizon to evaluate the current status and expected future of the nanomaterials market. The historical progress of each market, toxicity information, and possible returns stemming from their use is taken into account to analyze the predictions. Our results suggest various trends for the associated costs and nanotoxicity of the studied materials.

[en] Hexagonal MCM-41 can be transformed into cubic MCM-48 and finally into spherical particles by the addition of alcohol during the synthesis of a mesoporous silica material. X-ray diffraction suggests that the structure of these spherical particles is of the MCM-41 type. Transmission electron microscopy however reveals that the structure of the mesoporous silica spherical particles consists of a core in the form of a truncated octahedron with an MCM-48 cubic structure and radial pores grown on the surfaces of the truncated octahedron. Spherical MCM particles therefore consist of a mixture of cubic and hexagonally arranged pores

[en] We present an efficient method for the quantification of crystalline versus amorphous phase content in mesoporous materials, making use of electron energy loss spectroscopy. The method is based on fitting a superposition of core-loss edges using the maximum likelihood method with measured reference spectra. We apply the method to mesoporous TiO₂ samples. We show that the absolute amount of the crystalline phase can be determined with an accuracy below 5%. This method takes also the amorphous phase into account, where standard X-ray diffraction is only quantitative for crystalline phases and not for amorphous phase

[en] Electron tomography is currently a versatile tool to investigate the connection between the structure and properties of nanomaterials. However, a quantitative interpretation of electron tomography results is still far from straightforward. Especially accurate quantification of pore-space is hampered by artifacts introduced in all steps of the processing chain, i.e., acquisition, reconstruction, segmentation and quantification. Furthermore, most common approaches require subjective manual user input. In this paper, the PORES algorithm “POre REconstruction and Segmentation” is introduced; it is a tailor-made, integral approach, for the reconstruction, segmentation, and quantification of porous nanomaterials. The PORES processing chain starts by calculating a reconstruction with a nanoporous-specific reconstruction algorithm: the Simultaneous Update of Pore Pixels by iterative REconstruction and Simple Segmentation algorithm (SUPPRESS). It classifies the interior region to the pores during reconstruction, while reconstructing the remaining region by reducing the error with respect to the acquired electron microscopy data. The SUPPRESS reconstruction can be directly plugged into the remaining processing chain of the PORES algorithm, resulting in accurate individual pore quantification and full sample pore statistics. The proposed approach was extensively validated on both simulated and experimental data, indicating its ability to generate accurate statistics of nanoporous materials. - Highlights: • An electron tomography reconstruction/segmentation method for nanoporous materials. • The method exploits the porous nature of the scanned material. • Validated extensively on both simulation and real data experiments. • Results in increased image resolution and improved porosity quantification

[en] Highlights: • Purely intra-epiphyseal stress injuries of the proximal tibial epiphysis are described for the first time. • The variation in the MRI findings of these injuries depending on the stage of maturation is demonstrated. • We postulate a patho-mechanism to explain the variations in site and appearance of stress injuries in this region. - Abstract: Stress induced injuries affecting the physeal plate or cortical bone in children and adolescents, especially young athletes, have been well described. However, there are no reports in the current English language literature of stress injury affecting the incompletely ossified epiphyseal cartilage. We present four cases of stress related change to the proximal tibial epiphysis (PTE) along with their respective magnetic resonance imaging (MRI) appearances ranging from subtle oedema signal to a pseudo-tumour like appearance within the epiphyseal cartilage. The site and pattern of intra-epiphyseal injury is determined by the type of tissue that is affected, the maturity of the skeleton and the type of forces that are transmitted through the tissue. We demonstrate how an awareness of the morphological spectrum of MRI appearances in intra-epiphyseal stress injury and the ability to identify concomitant signs of stress in other nearby structures can help reduce misdiagnosis, avoid invasive diagnostic procedures like bone biopsy and reassure patients and their families