Determination of chemical forms of 14C in liquid discharges from nuclear power plants.

Developments of radioanalytical methods for determination of radiocarbon in wastewaters from nuclear power plants (NPP) with pressurized light water reactors, which would distinguish between the dissolved organic and inorganic forms have been carried out. After preliminary tests, the method was used to process pilot samples from wastewater outlets from the Temelín and Dukovany NPPs (Czech Republic). The results of analysis of pilot water samples collected in 2015 indicate that the instantaneous 14C releases into the water streams would be about 7.10-5 (Temelín) and 4.10-6 (Dukovany) of the total quantity of the 14C liberated into the environment.

The valley system of the Jihlava river and Mohelno reservoir with enhanced tritium activities.

The Dukovany nuclear power plant (NPP Dukovany) releases liquid effluents, including HTO, to the Mohelno reservoir, located in a deep valley. Significantly enhanced tritium activities were observed in the form of non-exchangeable organically bound tritium in the surrounding biota which lacks direct contact with the water body. This indicates a tritium uptake by plants from air moisture and haze, which is, besides the uptake by roots from soil, one of the most important mechanisms of tritium transfer from environment to plants. Results of a pilot study based on four sampling campaigns in 2011-2015 are presented and discussed, with the aim to provide new information on tritium transport in the Mohelno reservoir - Jihlava River - plants ecosystems.

[Superficial thrombophlebitis of the lower limbs from the surgeons point of view]. / Povrchní tromboflebitida dolních koncetin z hlediska chirurga.

INTRODUCTION: A new consensus on the management of superficial thrombophlebitis (STP) from the Central European Vascular Forum (CEVF) for the diagnosis and treatment of STP recommends anticoagulation treatment either with Fondaparinux 2.5 mg for at least 45 days or with low molecular weight heparin (LMWH) for 4 weeks in patients with thrombosis of GSV/SSV proven by duplex ultrasonography (DUS) and with thrombus length exceeding 5 cm. The dosage and duration of anticoagulation treatment depend on the associated diseases and other risk factors for TVE. Many options for doses an duration of treatment are referred to in the literature. Emergency surgery is not recommended. The aim of this study is to demonstrate the role of DUS examination in acute ascending thrombophlebitis (ASTP) of the GSV, and demonstrate the efficiency of surgical treatment - crossectomy and phlebectomy of thrombosed GSV/SSV. MATERIAL AND METHODS: The authors present their clinical experience with DUS diagnosis and surgical treatment of acute ascending thrombophlebitis in GSV/SSV on 66 patients with 68 operations. In two of them bilateral crossectomy was performed. In the diagnosis it is necessary to perform DUS examination after clinical diagnosis of acute thrombophlebitis. It should be done bilaterally, not only in the affected limb. DUS confirms the measure, progression and eventually ascension of the thrombosis on the trunk of the GSV/SSV and perforating veins. Progress of the thrombotic process from the thigh to the SF/SP junction is usually a matter of a few hours. Daily ultrasound assessment should therefore be performed in acute thrombophlebitis, even during anticoagulation therapy. Thrombus near the SF/SP junction is a reason for urgent surgery - crossectomy and phlebectomy. RESULTS: 66 patients were operated on under general anaesthesia without any complications. A large hematoma in the subinguinal region developed in one patient after surgery. A 50-year-old patient returned with colliquation of the residual varicose vein on the lower leg. Outpatient incision and evacuation had to be performed 3 weeks after surgery. Anticoagulation therapy with warfarin was started in two patients. The other patients were discharged 4 to 6 days following surgery without any problems. Post-operative anti-coagulation in other patients was not longer than 2 weeks. CONCLUSION: Urgent crossectomy and phlebectomy represent a reliable method of treatment in the management of acute ascending thrombophlebitis of GSV/SSV, guaranteeing prophylaxis of complications, especially in pregnant women with PT in the later phase of pregnancy. Surgical treatment destroys the damaged vein with crossectomy as a potential cause of deep vein thrombosis (DVT), pulmonary embolism (PE) and STP recurrence. After anticoagulation therapy the affected vein remains in situ. It can potentially cause the recurrence of STP, and DVT and PE may develop.

Extended use of alanine irradiated in experimental reactor for combined gamma- and neutron-dose assessment by ESR spectroscopy and thermal neutron fluence assessment by measurement of (14)C by LSC.

Gamma- and neutron doses in an experimental reactor were measured using alanine/electron spin resonance (ESR) spectrometry. The absorbed dose in alanine was decomposed into contributions caused by gamma and neutron radiation using neutron kerma factors. To overcome a low sensitivity of the alanine/ESR response to thermal neutrons, a novel method has been proposed for the assessment of a thermal neutron flux using the (14)N(n,p) (14)C reaction on nitrogen present in alanine and subsequent measurement of (14)C by liquid scintillation counting (LSC).

Enhanced activities of organically bound tritium in biota samples.

A pilot study aimed on possible occurrence of elevated activity of non-exchangable organically bound tritium (NE-OBT) in biota was performed. The first results showed a significant surplus of NE-OBT activity in biota of the valley of Mohelno reservoir and Jihlava river. The liquid releases of HTO from the nuclear power plant Dukovany is the source of tritium in this area. This area can be a source of various types of natural samples for future studies of tritium pathways.

An ATP-dependent step is required for the translocation of microinjected precursor mRNA into nuclear speckles.

Nuclear speckles (speckles) represent a distinct nuclear compartment within the interchromatin space and are enriched in splicing factors. In a previous study (Melcák et al., 2001), it has been shown that the pre-spliceosomal assembly on microinjected splicing-competent precursor mRNA takes place in the speckles, and it has been suggested that the targeting of RNA into speckes consists of two interdependent steps, namely the diffusion process, followed by the energy-dependent translocation of RNA into the speckles. In the present study, we confirm the existence of these two steps and show that this latter translocation is ATP dependent.