For patients suffering from brain tumor, prognosis estimation and treatment decisions are made by a multidisciplinary team based on a set of preoperative MR scans. Currently, the lack of standardized ...and automatic methods for tumor detection and generation of clinical reports represents a major hurdle. In this study, we investigate glioblastomas, lower grade gliomas, meningiomas, and metastases, through four cohorts of up to 4000 patients. Tumor segmentation models were trained using the AGU-Net architecture with different preprocessing steps and protocols. Segmentation performances were assessed in-depth using a wide-range of voxel and patient-wise metrics covering volume, distance, and probabilistic aspects. Finally, two software solutions have been developed, enabling an easy use of the trained models and standardized generation of clinical reports: Raidionics and Raidionics-Slicer. Segmentation performances were quite homogeneous across the four different brain tumor types, with an average true positive Dice ranging between 80% and 90%, patient-wise recall between 88% and 98%, and patient-wise precision around 95%. With our Raidionics software, running on a desktop computer with CPU support, tumor segmentation can be performed in 16 to 54 seconds depending on the dimensions of the MRI volume. For the generation of a standardized clinical report, including the tumor segmentation and features computation, 5 to 15 minutes are necessary. All trained models have been made open-access together with the source code for both software solutions and validation metrics computation. In the future, an automatic classification of the brain tumor type would be necessary to replace manual user input. Finally, the inclusion of post-operative segmentation in both software solutions will be key for generating complete post-operative standardized clinical reports.
Summary
When an As spermatogonium divides to form a pair of Apr spermatogonia the two daughter cells stay interconnected by an intercellular bridge. These cytoplasmic bridges form after every ...subsequent division leading to large clones of interconnected germ cells. Cohorts of spermatogonia maintain synchronous development throughout spermatogenesis, which has been attributed to the presence of these intercellular bridges. To examine whether apoptotic signals are transduced through the intercellular bridges we studied germ cell apoptosis in whole mounts of seminiferous tubules from non‐irradiated and irradiated mouse testes, using whole mount seminiferous tubules and confocal microscopy. This allowed us to use TUNEL staining of apoptotic germ cells and at the same time to study these apoptotic germ cells in their topographical context. Our results show that in response to ionizing radiation single spermatogonia within a clone can undergo apoptosis without affecting their neighboring cells. Additionally, also early spermatocytes were shown to undergo apoptosis individually. Both radiation‐induced spermatogonial apoptosis and spontaneous apoptosis of spermatocytes are caused by DNA damage of individual cells. Degeneration of healthy spermatogonia because of regulatory signals, however, follows other death inducing mechanisms, which lead to apoptosis of chains of interconnected spermatogonia.
During a European Union Concerted Action study on species introductions, an intercalibration workshop on ship ballast water sampling techniques considered various phytoplankton and zooplankton ...sampling methods. For the first time, all the techniques presently in use worldwide were compared using a plankton tower as a model ballast tank spiked with the brine shrimp and oyster larvae while phytoplankton samples were taken simultaneously in the field (Helgoland Harbour, Germany). Three cone-shaped and 11 non-cone shaped plankton nets of different sizes and designs were employed. Net lengths varied from 50 to 300 cm, diameters 9.7–50 cm, and mesh sizes 10–100 μm. Three pumps, a Ruttner sampler, and a bucket previously used in ballast water sampling studies were also compared. This first assessment indicates that for sampling ballast water a wide range of techniques may be needed. Each method showed different results in efficiency and it is unlikely that any of the methods will sample all taxa. Although several methods proved to be valid elements of a hypothetical `tool box' of effective ship sampling techniques. The Ruttner water sampler and the pump P30 provide suitable means for the quantitative phytoplankton sampling, whereas other pumps prevailed during the qualitative trial. Pump P15 and cone-shaped nets were the best methods used for quantitative zooplankton sampling. It is recommended that a further exercise involving a wider range of taxa be examined in a larger series of mesocosms in conjunction with promising treatment measures for managing ballast water.
A major vector for unintentional species introductions is international shipping. A wide range of organisms have been transported over long distances in ships' ballast tanks and as hull fouling. ...Although many desk studies and ship sampling programmes have been carried out, little information is available on changing numbers of individuals in ballast water during voyages. Detailed information could assist in evaluating the dimension of species import and future risks of unintentional species introductions by ballast water. The first European study, organised as a concerted action team and financed by the European Union, carried out several long-term and short-term workshops on board ships undertaking international voyages. The preliminary results from sampling the ballast water of the first four ocean-going workshops of this Concerted Action showed a decrease in numbers of specimens and taxa over time.
The results of a policy of selective cholangiography were assessed in 400 patients undergoing laparoscopic cholecystectomy. Preoperative endoscopic retrograde cholangiopancreatography (ERCP) was ...performed in 81 patients (20 per cent) of whom 31 (38 per cent) showed definite or possible evidence of stones in the bile duct. Seventeen of the 400 patients underwent intraoperative cholangiography and the majority of these (12) were normal. After a minimum follow-up of 1 year, 17 patients (4 per cent) have had ERCP for suspected residual duct stones. Eight (2 per cent) of these revealed stones and all were successfully treated with sphincterotomy and duct clearance. Preoperative and postoperative ERCP was not associated with mortality or major morbidity. No major duct injury occurred and none was diagnosed within 2 years of operation. Routine intraoperative cholangiography is not a necessary part of laparoscopic cholecystectomy in the presence of an efficient and safe ERCP service.
We report the fabrication of polymer light emitting diodes from a cyano-substituted thienylene phenylene vinylene copolymer. Photoluminescence and electroluminescence studies of these devices show a ...broad emission spectrum which peaks in the near infra-red and extends out to a wavelength of 1000nm. Bilayer structures using poly(
p-phenylene vinylene) as a hole transport layer and the cyano-copolymer as the emissive layer showed improved electroluminescence internal quantum efficiency of up to 0.2%..
