Cesium and iodine release from fluoride-based molten salt reactor fuel.

Cesium and iodine, which are formed during a fission process in a nuclear reactor, are considered as major fission products responsible for the environmental burden in case of a nuclear accident. From the safety point of view, it is thus important to understand their release mechanism when overheating of the reactor core occurs. This work presents an experimental investigation of the behaviour of caesium iodide and caesium fluoride in fluoride based molten salt reactor fuel during high temperature events. It has been demonstrated that CsF will be retained in the fuel salt and thus its volatility will be significantly reduced, while CsI will not dissolve in the fluoride-based fuel matrix and will thus remain more volatile. The influence of the presence of CsI and CsF on the melting behaviour of the fuel has been investigated using calorimetry, revealing their negligible effects.

[Neuroendocrine neoplasms of the breast]. / Neuroendokrine Neoplasien der Mamma.

Neuroendocrine neoplasms (NEN) of the breast are specific tumor entities. According to the literature up to 5% of breast neoplasms are malignant epithelial neoplasms of the breast. They are defined by a neuroendocrine (NE) architecture and cytology combined with an expression of the neuroendocrine vesicle markers chromogranin A and/or synaptophysin. The diagnosis is supplemented by the receptor status and the proliferative activity. According to the World Health Organization (WHO) classification of 2012 the following groups of NEN are distinguished: (1) invasive breast carcinoma with NE differentiation, (2) well-differentiated neuroendocrine tumor (NET) and (3) poorly differentiated small cell carcinoma (NEC). This review article focuses on (1) the definition and basic principles of diagnostics, (2) the history, nomenclature and WHO classification from 2003 and 2012, (3) the frequency of breast NEN, (4) the hereditary background and functional activity, (5) the expression of receptors and (6) the possible clinical implications. In addition, the first results of a retrospective single center study (n = 465 patients with breast cancer over a time period of 4 years) on the frequency of NEN of the breast at the Breast Center of the University Hospital Düsseldorf are presented. In this study a frequency of 4.5% of NEN was found based on a diagnostic cut-off of > 50% Chromogranin A and/or synaptophysin positive tumor cells.

Quantitative molecular plating of large-area 242Pu targets with improved layer properties.

For measurements of the neutron-induced fission cross section of 242Pu, large-area (42cm2) 242Pu targets were prepared on Ti-coated Si wafers by means of constant current density molecular plating. Radiochemical separations were performed prior to the platings. Quantitative deposition yields (>95%) were determined for all targets by means of alpha-particle spectroscopy. Layer densities in the range of 100-150µg/cm2 were obtained. The homogeneity of the targets was studied by radiographic imaging. A comparative study between the quality of the layers produced on the Ti-coated Si wafers and the quality of layers grown on normal Ti foils was carried out by applying scanning electron microscopy and energy dispersive X-ray spectroscopy. Ti-coated Si wafers resulted clearly superior to Ti foils in the production of homogeneous 242Pu layers with minimum defectivity.

[Neuroendocrine neoplasms of the distal jejunum and ileum]. / Neuroendokrine Neoplasien des distalen Jejunums und Ileums.

Neuroendocrine neoplasms (NEN) of the distal jejunum and ileum derive from serotonin-producing enterochromaffin (EC) cells. Due to their low proliferation rate and their infiltrative growth, they are often discovered at an advanced disease stage when metastasis has already occurred. The biology of these tumours is different from other NEN of the digestive tract. In order to standardise and improve diagnosis and therapy, the guidelines for the diagnosis and clinical management of jejuno-ileal NEN as well as for the management of patients with liver and other distant metastases from NEN were revised by the European Neuroendocrine Tumour Society (ENETS) in 2012. This review focuses on aspects relevant for surgical pathology.

Identification of serum angiopoietin-2 as a biomarker for clinical outcome of colorectal cancer patients treated with bevacizumab-containing therapy.

BACKGROUND: The combination of chemotherapy with the vascular endothelial growth factor (VEGF) antibody bevacizumab is a standard of care in advanced colorectal cancer (CRC). However, biomarkers predicting outcome of bevacizumab-containing treatment are lacking. As angiopoietin-2 (Ang-2) is a key regulator of vascular remodelling in concert with VEGF, we investigated its role as a biomarker in metastatic CRC. METHODS: Serum Ang-2 levels were measured in 33 healthy volunteers and 90 patients with CRC. Of these, 34 had metastatic disease and received bevacizumab-containing therapy. To determine the tissue of origin of Ang-2, quantitative real-time PCR was performed on microdissected cryosections of human CRC and in a murine xenograft model of CRC using species-specific amplification. RESULTS: Ang-2 originated from the stromal compartment of CRC tissues. Serum Ang-2 levels were significantly elevated in patients with metastatic CRC compared with healthy controls. Amongst patients receiving bevacizumab-containing treatment, low pre-therapeutic serum Ang-2 levels were associated with a significant better response rate (82 vs 31%; P<0.01), a prolonged median progression-free survival (14.1 vs 8.5 months; P<0.01) and a reduction of 91% in the hazard of death (P<0.05). CONCLUSION: Serum Ang-2 is a candidate biomarker for outcome of patients with metastatic CRC treated with bevacizumab-containing therapy, and it should be further validated to customise combined chemotherapeutic and anti-angiogenic treatment.

[Upper airway obstruction (foreign bodies excluded)]. / Obstruction des voies aériennes supérieures (à l'exclusion des corps étrangers).

Upper airway obstruction is a frequent cause of admission to the emergency department and the intensive care unit. Symptoms are mainly represented by dyspnea and stridor. Severity must be rapidly assessed to allow adapted treatment and avoid cardiac arrest and hypoxic encephalopathy. The possible etiologies are numerous, with acquired and congenital ones, but the majority is represented by laryngitis, lymphoid hypertrophy and laryngotracheomalacia. In case of respiratory failure, treatment must first establish airway patency with bag and mask ventilation, and then intubation. If vital prognosis is not threatened, biologic, radiologic or endoscopic examination can be performed to identify the cause of the obstruction and treat it.

Role of antigen-induced cytokine release in atopic pruritus.

In order to further evaluate the role of cytokines in the induction of atopic pruritus, leukocytes from 10 atopic eczema patients or 10 nonallergic controls were stimulated in vitro with mite or birch pollen antigen for 1 and 4 days. Subjects were prick-tested with the supernatants, and whealing and itching were evaluated 20 and 60 min later. The supernatants were also examined for the contents of GM-CSF, IL-2, IL-6 and IL-8 by ELISA and TNFalpha. Two hours prior to testing, the antihistamine cetirizine (20 mg) or a placebo tablet were given to the patients according to a randomized, double-blind study protocol. After pricking with antigen-stimulated leukocyte supernatants, 6 of 10 patients but no controls reacted mostly at 20 min with whealing and/or pruritus. In the cetirizine-treated group, no decrease in these skin reactions was seen compared to placebo. Analysis for cytokines showed increased levels of IL-8 in allergen-stimulated samples, with no correlation to the induction of itching or whealing by these supernatants. IL-6 levels were low and variable, and GM-CSF, IL-2 and TNFalpha levels were always below standard values. These data show that leukocytes selectively release IL-8 in response to in vitro antigen stimulation. They furthermore provide additional support for the concept that as yet to be identified products play a role in atopic pruritus.

Phacomatosis pigmentokeratotica: a patient with the rare melanocytic-epidermal twin nevus syndrome.

We describe a 10-year-old girl affected with a speckled lentiginous nevus and an epidermal nevus of the organoid type on corresponding parts of the body. On histopathological examination, the lesions showed epidermal hyperpigmentation and melanocytic hyperplasia on the one hand and verrucous epidermal acanthosis with sebaceous hyperplasia on the other hand. Except for a minor deviation of the spine, the patient had no obvious extracutaneous symptoms. Happle et al. have recently interpreted the rare co-occurrence of these two types of nevi in spatial proximity as an example of twin spotting in human skin and proposed the name 'phacomatosis pigmentokeratotica'. In most cases, additional skeletal or neurological anomalies are found. These are dissimilar from the extracutaneous symptoms of the sebaceous nevus syndrome, from which phacomatosis pigmentokeratotica should be distinguished. Molecular studies are needed to prove the concept of twin spotting and to reveal a link to the extracutaneous manifestations.

Pruritogenic effects of mitogen-stimulated peripheral blood mononuclear cells in atopic eczema.

The etiology of atopic pruritus is unclear and seems mostly histamine-independent. In order to investigate non-mast cells as possible sources of pruritogenic agents, peripheral blood mononuclear cells from 12 atopic eczema patients and 12 controls were incubated in vitro for 24 h with phytohemagglutinin or concanavalin A (both at 10 micrograms/ml) or with medium alone, and each subject was tested with his own cell supernatants and lysates by prick testing and by application on tape-stripped skin. Histamine (0.1%) and substance P (500 microM) were tested in comparison, and reactions were observed for up to 24 h. Cell supernatants were also analysed for their contents of several cytokines. Lymphocyte cell extracts or supernatants failed to cause symptoms in controls but induced whealing in 6 and itching in 3 patients on prick testing within 5 min, lasting for 30 min in 2 patients and persisting for 6 h in 1 patient. Histamine caused itching in all controls and in 7 patients within 5 min on prick testing, with decreasing reactivity at later times. Substance P yielded results with lower values. With all three types of test reagents, fewer subjects reacted on tape stripped skin. High levels of interleukins 2 and 6, low levels of interferon and no detectable levels of interleukin 4 and tumour necrosis factor were measured in stimulated cell supernatants and extracts, with even lower levels in subjects exhibiting skin reactivity. These findings thus provide evidence that as yet unidentified mononuclear cell products may be involved in whealing and itching associated with atopic eczema.

Expression of the high affinity IgE-receptor on human Langerhans' cells. Elucidating the role of epidermal IgE in atopic eczema.

Epidermal Langerhans' cells have previously been shown to bear IgE molecules, particularly in atopic dermatitis skin. Using two highly specific antibodies against the antibody-binding chain of the high affinity IgE-receptor, 29C6 and 6F7, we here provide evidence that Langerhans' cells express this receptor in both normal skin (foreskin) and in lesional skin of patients with atopic and stasis eczema. A specific antibody against the low affinity IgE-receptor, Tü1, showed only a low expression of this receptor. This finding has important potential functional implications for the role of Langerhans' cells in transepidermal, IgE-mediated allergy.

Calciuric response to 1,25-(OH)2D3 in early renal failure.

In 10 patients with early renal failure (glomerular filtration rate between 30 and 80 ml/min/1.73 m2) without nephrotic syndrome and in 13 controls the calciuric response to increasing oral doses of calcitriol [1,25-(OH)2D3] (0.25; 0.5; 1.0; 1.5 micrograms/day) was evaluated. Patients had initially normal plasma calcitriol levels, normocalcemia and hypocalciuria. With calcitriol doses up to 1 microgram/day, the increment of UVCa was less in patients. Only at 1.5 micrograms/day the calciuria of patients reached the baseline calciuria of controls. The data document that 1.0 microgram calcitriol per day is required to normalize UVCa in patients with early renal failure and normal calcitriol levels. Blunted calciuric response to low doses of calcitriol is compatible with an altered dose-response relationship.