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Angiogenesis is the process of new blood vessels growing from existing vasculature. Visualizing them as a three-dimensional (3D) model is a challenging, yet relevant, task as it would be of great help to researchers, pathologists, and medical doctors. A branching analysis on the 3D model would further facilitate research and diagnostic purposes. In this paper, a pipeline of vision algorithms is elaborated to visualize and analyze blood vessels in 3D from formalin-fixed paraffin-embedded (FFPE) granulation tissue sections with two different staining methods. First, a U-net neural network is used to segment blood vessels from the tissues. Second, image registration is used to align the consecutive images. Coarse registration using an image-intensity optimization technique, followed by finetuning using a neural network based on Spatial Transformers, results in an excellent alignment of images. Lastly, the corresponding segmented masks depicting the blood vessels are aligned and interpolated using the results of the image registration, resulting in a visualized 3D model. Additionally, a skeletonization algorithm is used to analyze the branching characteristics of the 3D vascular model. In summary, computer vision and deep learning is used to reconstruct, visualize and analyze a 3D vascular model from a set of parallel tissue samples. Our technique opens innovative perspectives in the pathophysiological understanding of vascular morphogenesis under different pathophysiological conditions and its potential diagnostic role.

Purpose: In order to build up a reliable dose monitoring system for boron neutron capture therapy (BNCT) applications at the TRIGA reactor in Mainz, a computer model for the entire reactor was established, simulating the radiation field by means of the Monte Carlo method. The impact of different source definition techniques was compared and the model was validated by experimental fluence and dose determinations., Methods: The depletion calculation code origen2 was used to compute the burn-up and relevant material composition of each burned fuel element from the day of first reactor operation to its current core. The material composition of the current core was used in a mcnp5 model of the initial core developed earlier. To perform calculations for the region outside the reactor core, the model was expanded to include the thermal column and compared with the previously established attila model. Subsequently, the computational model is simplified in order to reduce the calculation time. Both simulation models are validated by experiments with different setups using alanine dosimetry and gold activation measurements with two different types of phantoms., Results: The mcnp5 simulated neutron spectrum and source strength are found to be in good agreement with the previous attila model whereas the photon production is much lower. Both mcnp5 simulation models predict all experimental dose values with an accuracy of about 5%. The simulations reveal that a Teflon environment favorably reduces the gamma dose component as compared to a polymethyl methacrylate phantom., Conclusions: A computer model for BNCT dosimetry was established, allowing the prediction of dosimetric quantities without further calibration and within a reasonable computation time for clinical applications. The good agreement between the mcnp5 simulations and experiments demonstrates that the attila model overestimates the gamma dose contribution. The detailed model can be used for the planning of structural modifications in the thermal column irradiation channel or the use of different irradiation sites than the thermal column, e.g., the beam tubes.

The activation of the biological shield is an important process for waste management considerations of nuclear facilities. The final activity can be estimated by modeling using the neutron flux density rather than the radiometric approach of activity measurements. Measurement series at the TRIGA reactor Vienna reveal that the flux density next to the biological shield is in the order of 10(9)cm(-2)s(-1) at maximum power; but it is strongly influenced by reactor installations. The data allow the estimation of the final waste categorization of the concrete according to the Austrian legislation., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Background and Objective: Rituximab has shown a high activity in relapsed follicular lymphomas when given alone. Further on, phase-II-studies indicate that its addition to chemotherapy may improve the response rate substantially. However, so far, prospective randomized studies have not been available., Patients and Methods: In 1998 the GLSG started a multicenter trial in patients with relapsed or refractory indolent lymphoma or mantle cell lymphoma. A fludarabine-containing regimen (FCM) was chosen for salvage therapy, with fludarabine 25 mg/m(2)/d 1-3, cyclophosphamide 200 mg/m(2) d 1-3 and mitoxantrone 8 mg/m(2) d 1. A total of four courses, every 4 weeks were given. Patients were prospectively randomized for FCM alone or the immunochemotherapy with R-FCM (375 mg/m(2) one day before FCM) RESULTS: About 147 randomized patients 93 had follicular, 40 mantle cell and 14 lymphoplasmocytic/-cytoid lymphoma. Statistical analysis was performed by sequential testing and indicated for 94 fully evaluable patients a significant advantage for the R-FCM-arm, with an overall response rate of 83 % as compared to 58%, when treated with FCM alone (CR: 35 % vs. 13 %). Similar improvements of remission rate were detected in the different lymphoma subgroups, especially in MCL (OR: 65 % vs. 33 %). Both treatment options were associated with hematological toxicities of grade III and IV, but well tolerated; infectious complications were rare, with no difference between the two treatment groups., Conclusion: This prospectively randomized trial demonstrates for the first time a significant improvement of the combined immunochemotherapy related to the remission rate in patients with relapsed or refractory indolent lymphoma.

Background and Objectives: From a technical point of view two problems arise during the collection of peripheral blood progenitor cells (PBPC): first, the volume of the apheresis product is often large, requiring volume reduction prior to cryopreservation. Second, the platelet (PLT) loss due to the harvesting of the buffy coat is an unwanted side effect. With respect to these problems, the present study was designed to compare programs for PBPC collection with discontinous-flow cell separators., Materials and Methods: Three different protocols for PBPC harvesting were investigated in 32 patients with malignancies. In the first protocol, the blood cell separator Haemonetics MCS 3p was used. In the second protocol using the same machine, the opening and closure of the stem cell valve was modified in combination with a centri surge to reduce the PLT loss. The MCS+ device with another configuration of the valves was used in the third protocol. PBPC were mobilised by chemotherapy plus cytokine administration or application of growth factor alone. Blood counts and CD34 antigen-expressing cells were determined before apheresis and in the PBPC product. Colony-forming unit granulocyte/macrophage (CFU-GM) were determined in the apheresis product., Results: 55 PBPC collections were carried out with a median end product volume of 105 ml. The median counts for CD34+ antigen-expressing cells and CFU-GM were 1.5x10(6 )and 2.5x10(4)/kg body weight, respectively. PLT loss was significantly lower in protocol III., Conclusion: The study reported here revealed that PBPC could be easily collected in a reduced product volume by the intermittent-flow cell separators. No additional centrifugation prior to cryopreservation was necessary to remove the plasma from the apheresis product. Patient's PLT loss was reduced by the centri surge technique but this still has to be improved.

Massive edema of the ovary is a rare condition found in young women as a result of partial or intermittent torsion of the ovary. Differentiation of this entity from tumors of the ovary is important to prevent overtreatment. Organ-preserving surgical treatment is indicated as the correct approach to management. We present a case of massive edema of the ovary associated with post partum involution of the female genital tract and discuss the clinical features in the light of the known literature.

The location of nucleosomes on rat satellite I DNA has been investigated using a new approach. Nucleosome cores were prepared from rat liver nuclei with micrococcal nuclease, exonuclease III and nucleases S1. From the total population of core DNA fragments the satellite-containing fragments were isolated by molecular cloning and the complete sequence of 50 clones was determined. The location of nucleosomes along the satellite sequence was found to be non-random. Our results show that nucleosomes occupy a number of positions on satellite I DNA. About 35 to 50% of all nucleosomes are positioned in two corresponding major sites, the remainder in about 16 less preferred sites. The major nucleosome positions are apparently strictly defined with the precision of a single base-pair. These results were confirmed by other approaches, including restriction nuclease digestion experiments. There are good indications of a defined long-range organization of the satellite chromatin fiber in two or more oligonucleosomal arrays with distinct nucleosome configurations.