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Article Modern agricultural industry is a source of a considerable amount of waste, which can come in various forms and states. Such waste, and not just agricultural waste in the form biomass, is highly desirable for further processing, depositing or utilising its energy potential. Briquetting technology is suitable for all these purposes. The briquetting press for industrial use is complex technical equipment. The economy of its operation has a major impact on the profitability of the produced briquettes and hence on the efficiency of waste and biomass processing as such. The paper deals with the energy demands of briquetting in terms of waste treatment and economic profitability of production in the whole context of waste processing as a whole.

Portal vein embolization or ligation (PVE/PVL) is part of most multi-stage liver procedures in the case of low future liver remnant volume (FLRV). PVE initiates compensatory hypertrophy of non-occluded liver parenchyma. This hypertrophy is stimulated by an increased volume of portal blood in the non-occluded veins. PVE results in adequate FLRV growth necessary for resection only in 63-96% patients. The aim of this publication is to summarize the possibilities of influencing liver regeneration after PVE/PVL in an experiment using cytokines (TNF-α, IL-6), a monoclonal antibody against TGF-β1 (MAB TGF-β1) and mesenchymal stem cells (MSC).The experimental model of PVE/PVL was chosen as best compatible for potential use in human medicine. 9 (control group), 9 (TNF-α group), 8 (IL-6 group), 6 (MSC group) and 7 piglets (MAB TGF-β1 group) were enrolled in individual studies. We performed laparotomy with PVL of the right-sided liver lobes under general anaesthesia. The following amounts of substances were applied in the non-occluded portal vein branches immediately after PVL: physiological solution (control group), recombinant porcine TNF-α (5 μg/kg), recombinant porcine IL-6 (0.5 μg/kg) and MSC (8.75, 14.0, 17.0, 17.5, 43.0 and 61.0 x 106 MSC). MAB TGF-β1 was applied 24 hours after PVL (40 μg/kg). Biochemical parameters were analysed repeatedly and FLRV ultrasound assessments were performed in the postoperative period. The experiments were ended on postoperative day 14 by sacryfiing the animals under general anaesthesia. Liver samples of hypertrophic and atrophic liver parenchyma were analysed.Repeated ultrasound assessments of the effects of MSC, TNF-α, IL-6 and MAB TGF-β1 compared with the physiological solution in the control group demonstrated statistically significant acceleration of FLRV growth in the experimental groups. For MSC, maximum growth was observed between postoperative days 3 and 7, on day 7 for TNF-α, between days 3 and 7 for MAB TGF-β1 and on day 7 for IL-6. Serum levels of AST and ALT increased after PVL and MSC whereas other biochemical parameters showed no statistically significant differences. We identified individual MSC using immunohistochemistry in the hypertrophic tissue of the MSC group. A statistically significant difference was observed in the number of binucleated hepatocytes, with their increased concentration in the IL-6 group.Application of IL-6, TNF-α, MAB TGF-β1 and MSC seems to provide suitable stimulation for achieving faster FLRV growth. Nevertheless, many controversial questions still remain to be answered with respect to the mechanism of their respective effects.Key words: liver regeneration portal vein embolization large animal experiment mesenchymal stem cells cytokines.

Sinusoidal obstruction syndrome (SOS) is a disease which is caused by toxic injury to hepatic sinusoids. This syndrome is most frequently caused by myeloablative radiochemotherapy in patients before hematopoietic stem cells transplantation and also by oxaliplatin mainly in patients with colorectal liver metastases. The aim of this study was to establish a large animal model of SOS, which would enable further study of this disease and facilitate translation of experimental outcomes into human medicine.A total of 27 domestic pigs (Prestice Black-Pied pig) were involved in this study (12 females). A group with a higher dose of monocrotaline (180 mg/kg) included 5 animals, and the remaining 22 pigs formed another group with a lower dose (36 mg/kg). Monocrotaline was administered via the portal vein and one week after the administration, partial hepatectomy of the left lateral liver lobe was performed. The animals were followed up for 3 weeks after monocrotaline administration. Regular ultrasound examinations were performed as well as examination of biochemical markers of liver and kidney functions and histological examination of liver parenchyma samples.The features of toxic liver injury which we observed in case of all animals were comparable with macroscopic and microscopic appearance of SOS. We recorded AST, ALT, bilirubin and ammonia elevation after monocrotaline administration. Echogenicity on ultrasound images of injured liver parenchyma was higher compared to echogenicity of healthy parenchyma. All the five animals from the first group with a higher monocrotaline dose had died before partial hepatectomy (1st-3rd day after monocrotaline administration). Death before partial hepatectomy occurred in 3 cases (6th and 7th day after monocrotaline administration) in the second group of 22 animals with a lower dose of monocrotaline. Death after partial hepatectomy occurred in 8 cases (7th-17th day after moncrotaline administration) in the same group. 11 animals survived the entire experimental period. The cause of death (in both groups) was metabolic failure in 10 animals and exsanguination in 4 animals, both due to severe hepatopathy. Death of 2 animals was not associated with monocrotaline intoxication (strangulation of small intestine, gastrectasis).We established a large animal model of SOS induced by monocrotaline administration (36 mg/kg via portal vein). This model can contribute to research of therapeutic modalities for this disease or to evaluation of surgical treatment of patients with SOS.Key words: sinusoidal obstruction syndrome monocrotaline oxaliplatin hepatotoxicity experimental model.

Korozivní preparáty (KP) slouží k vizualizaci a hodnocení morfologie dutých struktur. KP s naplněným kapilárním řečištěm umožňují za pomoci zobrazovacích metod získání dat použitelných pro matematické modelování orgánové perfuze. Náročnost přípravy KP stoupá s objemem cévního řečiště, proto byly touto metodou doposud zkoumány zejména malé živočišné druhy. Cílem této studie bylo optimalizovat protokoly přípravy korozivních preparátů různých orgánů prasete domícího, a to vzhledem k dostupnosti těchto orgánů a významu prasete domácího v experimentální medicíně. Corrosion casts (CCs) are used for the visualization and assessment of hollow structures. CCs with filled capillaries enable (with the help of imaging methods) to obtain data for mathematical organ pefusion modelling. As the processing is more difficult in case of organs with greater volume of the vasculature, mainly organs from small animals have been cast up to now. The aim of this study was to optimize the protocol of corrosion casting of different organs of pig. Porcine organs are relatively easily accessible and frequently used in experimental medicine.

Radiofrequency ablation (RFA) is a well-established method for palliative therapy of unresectable liver tumors. We use an open or percutaneous approach for the treatment of colorectal liver metastases (CLM).Clinical data of patients undergoing percutaneous or open RFA for CLM between January 2001 and January 2015 were included in the retrospective study. We evaluated clinical factors for overall survival (OS), no evidence of disease (NED) and non-ablation in relation to tumor sizes and numbers, type of approach and type of used probes.147 patients underwent RFA for CLM in this time period. Mean age was 65 years. 168 RFAs were performed in total. OS was influenced by a high number of censors. OS for the first and third years was 93.6% and 61% with no statistical differences between the percutaneous and open approach. NED was significantly shorter in patients with the percutaneous approach. NED was not influenced neither by size nor number of the lesions. A higher risk of non-ablation was observed as statistically significant in patients with percutaneous RFA. A higher, although not statistically significant, risk of non-ablation was also observed for larger metastases. Patients with percutaneous RFA showed a shorter stay in the hospital and fewer complications.RFA is an alternative approach to the treatment of unresectable CLM. In our study the open approach was associated with a lower risk of non-ablation. Percutaneous RFA showed a lower risk of complications and a shorter stay in the hospital.radiofrequency ablation percutaneous RFA colorectal liver metastases CLM palliative therapy.