Interactions of Mycobacterium bovis with protozoa and the occurrence of Mycobacterium bovis in environmental protozoa

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Interactions of Mycobacterium bovis with protozoa and the occurrence of Mycobacterium bovis in environmental protozoa.

Bovine tuberculosis is in the UK a persistent disease, affecting cattle and badgers. The latter is suspected to be a reservoir for Mycobacterium bovis but the transmission between badgers and cattle remains unclear. Mycobacteria have been shown to survive ingestion by protozoa and some even multiplied inside amoebas. The aim of this study was to investigate some interactions of Acanthamoeba castellanii and Tetrahymena pyriformis with M bovis. Firstly, the long term survival of the bacilli in protozoa was monitored. Secondly, it was investigated whether bacilli internalized in protozoa cysts are protected from hypochlorous acid and desiccation. Thirdly, the identification of M bovis in environmental protozoa isolated from badger latrines was attempted. The long term incubation of M. bovis with A. castellanii showed that the amoebas had a negative effect on the survival of virulent M. bovis. M. bovis was not detectable after 6 months of coincubation but remained viable at high concentrations in the control experiments. This effect however, could not be seen in T. pyriformis. Cysts of A. castellanii did not protect M bovis from hypochlorous acid and desiccation. Results indicate that M. bovis was more susceptible to hypochlorous acid after the encystment in comparison with the controls. These findings suggest that A. castellanii contributes to the decrease of M. bovis and therefore, it can be suggested that protozoa might have a negative impact on the survival M. bovis in the environment. In one of the samples taken from Woodchester Park, acid fast rods could be identified. Acid fast microorganisms were also identified in trophozoites of protozoa. This indicates that trophozoites of enviromnental protozoa might be carrier of mycobacteria and possibly M. bovis. An infection with bacilli-containing trophozoites might therefore be a potential route of transmission between the enviromnent and animals

Endurance and Resistance Training Affect High Fat Diet-Induced Increase of Ceramides, Inflammasome Expression, and Systemic Inflammation in Mice

The study aimed to investigate the effects of differentiated exercise regimes on high fat-induced metabolic and inflammatory pathways. Mice were fed a standard diet (ST) or a high fat diet (HFD) and subjected to regular endurance training (ET) or resistance training (RT). After 10 weeks body weight, glucose tolerance, fatty acids (FAs), circulating ceramides, cytokines, and immunological mediators were determined. The HFD induced a significant increase in body weight and a disturbed glucose tolerance (p<0.05). An increase of plasma FA, ceramides, and inflammatory mediators in adipose tissue and serum was found (p<0.05). Both endurance and resistance training decreased body weight (p<0.05) and reduced serum ceramides (p<0.005). While RT attenuated the increase of NLRP-3 (RT) expression in adipose tissue, ET was effective in reducing TNF-α and IL-18 expression. Furthermore, ET reduced levels of MIP-1γ, while RT decreased levels of IL-18, MIP-1γ, Timp-1, and CD40 in serum (p<0.001), respectively. Although both exercise regimes improved glucose tolerance (p<0.001), ET was more effective than RT. These results suggest that exercise improves HFD-induced complications possibly through a reduction of ceramides, the reduction of inflammasome activation in adipose tissues, and a systemic downregulation of inflammatory cytokines

Unmet needs in the diagnosis and treatment of Romanian patients with bilio-pancreatic tumors: results of a prospective observational multicentric study

Background. Biliopancreatic tumors (BPT) are among the most aggressive solid malignancies, and their incidence is rising. Good patient outcome relies heavily on a multidisciplinary approach to therapy, including timely access to endoscopy, surgery and chemo/radiotherapy. We aimed to evaluate current practices as reflected in the management and outcome of patients diagnosed with BPT in the setting of a low-resource medical system in order to identify areas suitable for improvement