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Purpose: The aim of this study was to analyze the epidemiology of polypharmacy in hospital psychiatry. Another aim was to investigate predictors of the number of drugs taken and the associated risks of drug–drug interactions and potentially inappropriate medications in the elderly. Methods: Daily prescription data were obtained from a pharmacovigilance project sponsored by the Innovations Funds of the German Federal Joint Committee. Results: The study included 47 071 inpatient hospital cases from eight different study centers. The mean number of different drugs during the entire stay was 6.1 (psychotropic drugs = 2.7; others = 3.4). The mean number of drugs per day was 3.8 (psychotropic drugs = 1.6; others = 2.2). One third of cases received at least five different drugs per day on average during their hospital stay (polypharmacy). Fifty‐one percent of patients received more than one psychotropic drug simultaneously. Hospital cases with polypharmacy were 18 years older (p < 0.001), more likely to be female (52% vs. 40%, p < 0.001) and had more comorbidities (5 vs. 2, p < 0.001) than hospital cases without polypharmacy. The risks of drug–drug interactions (OR = 3.7; 95% CI = 3.5–3.9) and potentially inappropriate medication use in the elderly (OR = 2.2; CI = 1.9–2.5) substantially increased in patients that received polypharmacy. Conclusion: Polypharmacy is frequent in clinical care. The number of used drugs is a proven risk factor of adverse drug reactions due to drug–drug interactions and potentially inappropriate medication use in the elderly. The potential interactions and the specific pharmacokinetics and ‐dynamics of older patients should always be considered when multiple drugs are used. [ABSTRACT FROM AUTHOR]

The aim of the study was to estimate and to compare effective doses in the elbow region resulting from four different x‐ray imaging modalities. Absorbed organ doses were measured using 11 metal oxide field effect transistor (MOSFET) dosimeters that were placed in a custom‐made anthropomorphic elbow RANDO phantom. Examinations were performed using Shimadzu FH‐21 HR radiography device, Siemens Sensation Open 24‐slice MSCT‐device, NewTom 5G CBCT device, and Planmed Verity CBCT device, and the effective doses were calculated according to ICRP 103 recommendations. The effective dose for the conventional radiographic device was 1.5 µSv. The effective dose for the NewTom 5G CBCT ranged between 2.0 and 6.7 µSv, for the Planmed Verity CBCT device 2.6 µSv and for the Siemens Sensation MSCT device 37.4 µSv. Compared with conventional 2D radiography, this study demonstrated a 1.4–4.6 fold increase in effective dose for CBCT and 25‐fold dose for standard MSCT protocols. When compared with 3D CBCT protocols, the study showed a 6‐19 fold increase in effective dose using a standard MSCT protocol. CBCT devices offer a feasible low‐dose alternative for elbow 3D imaging when compared to MSCT. [ABSTRACT FROM AUTHOR]

Purpose: In order to attain anatomical models, surgical guides and implants for computer‐assisted surgery, accurate segmentation of bony structures in cone‐beam computed tomography (CBCT) scans is required. However, this image segmentation step is often impeded by metal artifacts. Therefore, this study aimed to develop a mixed‐scale dense convolutional neural network (MS‐D network) for bone segmentation in CBCT scans affected by metal artifacts. Method: Training data were acquired from 20 dental CBCT scans affected by metal artifacts. An experienced medical engineer segmented the bony structures in all CBCT scans using global thresholding and manually removed all remaining noise and metal artifacts. The resulting gold standard segmentations were used to train an MS‐D network comprising 100 convolutional layers using far fewer trainable parameters than alternative convolutional neural network (CNN) architectures. The bone segmentation performance of the MS‐D network was evaluated using a leave‐2‐out scheme and compared with a clinical snake evolution algorithm and two state‐of‐the‐art CNN architectures (U‐Net and ResNet). All segmented CBCT scans were subsequently converted into standard tessellation language (STL) models and geometrically compared with the gold standard. Results: CBCT scans segmented using the MS‐D network, U‐Net, ResNet and the snake evolution algorithm demonstrated mean Dice similarity coefficients of 0.87 ± 0.06, 0.87 ± 0.07, 0.86 ± 0.05, and 0.78 ± 0.07, respectively. The STL models acquired using the MS‐D network, U‐Net, ResNet and the snake evolution algorithm demonstrated mean absolute deviations of 0.44 mm ± 0.13 mm, 0.43 mm ± 0.16 mm, 0.40 mm ± 0.12 mm and 0.57 mm ± 0.22 mm, respectively. In contrast to the MS‐D network, the ResNet introduced wave‐like artifacts in the STL models, whereas the U‐Net incorrectly labeled background voxels as bone around the vertebrae in 4 of the 9 CBCT scans containing vertebrae. Conclusion: The MS‐D network was able to accurately segment bony structures in CBCT scans affected by metal artifacts. [ABSTRACT FROM AUTHOR]

Purpose: Imaging phantoms are widely used for testing and optimization of imaging devices without the need to expose humans to irradiation. However, commercially available phantoms are commonly manufactured in simple, generic forms and sizes and therefore do not resemble the clinical situation for many patients. Methods: Using 3D printing techniques, we created a life‐size phantom based on a clinical CT scan of the thorax from a patient with lung cancer. It was assembled from bony structures printed in gypsum, lung structures consisting of airways, blood vessels >1 mm, and outer lung surface, three lung tumors printed in nylon, and soft tissues represented by silicone (poured into a 3D‐printed mold). Results: Kilovoltage x‐ray and CT images of the phantom closely resemble those of the real patient in terms of size, shapes, and structures. Surface comparison using 3D models obtained from the phantom and the 3D models used for printing showed mean differences <1 mm for all structures. Tensile tests of the materials used for the phantom show that the phantom is able to endure radiation doses over 24,000 Gy. Conclusions: It is feasible to create an anthropomorphic thorax phantom using 3D printing and molding techniques. The phantom closely resembles a real patient in terms of spatial accuracy and is currently being used to evaluate x‐ray‐based imaging quality and positional verification techniques for radiotherapy. [ABSTRACT FROM AUTHOR]

Root fractures in the middle and apical thirds of the root are treated by repositioning and for approximately 6 weeks of immobilization while those in the cervical third are immobilized for 3 months. Even though the results are good, some root-fractured teeth are lost and replaced by dental implants or fixed partial dentures. One historic but effective treatment option for those root fractures with unfavorable crown to root ratios is an endodontic implant in middle and apical third root fractures. This method offers immediate stable fixation of a crown and its coronal root segment to the underlying alveolar bone. This report documents the long-term survival of a tooth treated with an endodontic implant. A 25-year-old male patient presented following a bicycle accident with a dislocated unfavorable root fracture in the middle third. The crown with the coronal root segment was secured to the bone using a commercially available endodontic implant. The apical part of the root was removed. Although the clinical and radiological follow-up results of the endodontic implant demonstrated a good clinical function and little bone loss, the implant ultimately had to be removed after 22 years of service due to pain and increasing mobility. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to retrospectively investigate the incidence and associated factors of dental trauma in patients with maxillofacial fractures at the VU Medical Center in Amsterdam. Material and methods Data from 707 patients who were treated surgically for maxillofacial fractures were evaluated. The data were collected retrospectively from patient files and other available databases. The data collected included date of fracture, age, gender, type of fracture, and injured teeth. Result Of the total 707 patients, 164 patients (23.2%) presented dental injuries associated with facial fractures. Mandibular condylar fractures, mandibular parasymphyseal fractures, Le Fort fractures, and mandibular body fractures were found to be significantly more associated with dental injury. Zygomatic arch or zygomatic complex fractures were significantly less associated with dental injury. Women had a significant higher risk of facial fractures with dental injuries than men. The maxilla demonstrated the highest incidence of injured teeth. The most affected teeth were the maxillary incisors (33.1%), followed by mandible incisors (13.6%), mandible molars (12.8%), and maxillary premolars (12.6%). Conclusion Our findings show a higher risk of dental injury among patients with a mandibular condylar fracture and mandibular parasymphyseal fracture but a lower risk of dental injury among patients with a zygomatic arch or zygomatic complex fracture. On average, patients had more than three injured teeth, with most of the injured teeth being in the upper jaw. The maxillary incisors, followed by the mandible incisors, were the most injured teeth. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess and compare the effective doses (ICRP 103) in the ankle region of X-ray imaging resulting from a multi slice computed tomography (MSCT) device, two cone beam CT (CBCT) devices and one conventional x-ray device. Methods: Organ dose measurements were performed using 20 metal oxide field effect transistor (MOSFET) dosimeters that were placed in a custom made anthropomorphic RANDO ankle phantom. The following scanners were assessed in this study: Siemens Sensation Open 24-slice MSCT-scanner (120 kVp, 54 mAs), NewTom 5G CBCT scanner (110 kVp, 2.3 - 59 mAs), Planmed Verity CBCT-scanner (90 kVp, 48 mAs), Shimadzu FH-21 HR direct radiography equipment (AP + LAT), (57 kVp, 16 mAs). Results: Measurements of the MSCT device resulted in 21.4 μSv effective dose. The effective doses of CBCTs were between 1.9 μSv and 14.3 μSv for NewTom 5G and 6.0 μSv for Planmed Verity. Effective doses for the Shimadzu FH-21 HR conventional radiography were 1.0 μSv (LAT) and 0.5 μSv (AP), respectively. Conclusions: Compared with a conventional 2D radiographic device, this study showed a 14-fold effective dose for standard MSCT and 1.3 -10 fold effective dose for standard CBCT protocols. CBCT devices offers a 3D view of ankle imaging and exhibited lower effective doses compared with MSCT. [ABSTRACT FROM AUTHOR]

The immunoreactivity of tubulin varies with the conditions of preparation and storage of the protein. Four different antisera to tubulin detected less than or about 10% of the tubulin present in purified rat brain microtubule protein either immediately after preparation or after storage at -196°C. Addition of salt to the storage buffer led to a partial recovery of immunoreactivity. After storage at -20°C or after transfer from -196°C to -20°C, the recovery of tubulin immunoreactivity varied with the concentration of microtubule protein. At concentrations higher than 2.0–2.5 mg/ml, tubulin remained non-immunoreactive. On decreasing the protein concentration, there was a progressive recovery of the immunoreactivity. Addition of salt to the storage buffer led to a full recovery whatever the protein concentration. Storage in 2 M glycerol prevented immunoreactivity in all the conditions. Phosphocellulose chromatography of microtubule protein lacking immunoreactivity yielded a pure tubulin that was fully immunoassayable. Transfer of microtubule protein from -20°C to -196°C led to a significant decrease of the amount of immunoassayable tubulin indicating that the alterations of tubulin immunoreactivity are reversible. Immunoreactivity of tubulin present in freshly prepared crude rat brain 100000 x g supernatant was also incompletely immunoreactive and increased after freezing at -20°C. Circular dichroic spectra showed that freezing at -20°C decreased the content of a helix from 41% (at -196°C) to 28% in purified microtubule protein. The percentage a helix was low in buffers of high ionic strength and high in the presence of glycerol irrespective of the storage temperature. Thus, the a helix content showed an inverse relationship to immunoreactivity and the availability of antigenic sites seems to be related to the conformation of tubulin. Although the ability of microtubule protein to polymerize was maintained after storage at -196°C and decreased after storage at -20°C, there was no direct relationship between immunoreactivity and the polymerization properties of tubulin. Our results show that care should be taken in the preparation of tubulin samples to be assayed by immunological techniques. Glycerol, which is often used to prepare and store tubulin, prevents the ability of tubulin to react with specific antibodies. Alterations of the availability of antigenic sites, observed in the presence of glycerol or salt or after freezing, seem to be related to changes of the conformation of tubulin. [ABSTRACT FROM AUTHOR]

The back-cover image shows the Ti/(Ba+Sr) ratio of tunable dielectric (Ba,Sr)TiO SB 3 sb thin films prepared by radio-frequency magnetron sputtering from nominally stoichiometric targets. Independent of the Ba/Sr ratio, the Ti content at the thinfilm surfaces, which is determined using in-situ X-ray photoelectron spectroscopy (XPS) measurements, varies substantially with deposition conditions. The composition at the surface varies as (Ba,Sr)TiO SB 3 sb ± I x i (Ba,Sr)O. [Extracted from the article]

Barium strontium titanate thin films with different Ba/Sr ratios deposited by radio‐frequency magnetron sputtering are studied with respect to their composition using in situ X‐ray photoelectron spectroscopy. The deposited samples can be described as either titanium‐rich or stoichiometric, with cation B/A ratios (i.e., ratios between the Ti and (Ba + Sr) concentrations) of 1.2–1.6 or 0.7–1.0, respectively. Volume sensitive compositional analysis using transmission electron microscopy shows a non‐stoichiometry, which is less pronounced than at the surface. X‐ray diffraction only shows cubic perovskite reflections. Together with photoelectron binding energy differences and full widths at half maxima of the Ti 2p and O 1s emissions, this indicates that all films consist of a single phase. The relation between oxygen concentration and B/A ratio further indicates that the deviation of stoichiometry is accommodated by removal or insertion of (Ba,Sr)O. The higher variation of (Ba,Sr)O content near the surface as compared to the bulk may be associated to an increased strain, which is proposed to contribute to surface roughening. [ABSTRACT FROM AUTHOR]