A comparative study of the in vitro activity of iodopropynyl butylcarbamate and amphotericin B against Prototheca spp. isolates from European dairy herds.

ABSTRACT The objective of this study was to assess the in vitro effect of iodopropynyl butylcarbamate (IPBC) and amphotericin B (AMB) on Prototheca zopfii genotype 2 and Prototheca blaschkeae isolates recovered from dairy herds of Belgium, France, Italy, Germany, and Poland. The combination of IPBC with AMB on Prototheca isolates and toxicity of IPBC to the bovine mammary epithelial cells were also evaluated. The in vitro activity of IPBC and AMB against 96 isolates of P. zopfii genotype 2 and 42 isolates of P. blaschkeae was performed. Minimum inhibitory concentrations (MIC) and minimum algicidal concentrations (MAC) of IPBC and AMB were determined. To determine any synergistic, additive, or antagonistic effect of the combination of IPBC and AMB, 2-dimensional checkerboard combination tests were also performed to calculate fractional inhibitory concentrations. Cytotoxicity analysis of IPBC to the bovine mammary epithelial cell line was performed using a 3-(4,5-dimethyl-2-thiazol-2yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. The MIC for 50 and 90% of isolates (MIC 50 and MIC 90 , respectively) for IPBC were 4 and 8 mg/L versus 0.5 and 1 mg/L for AMB, respectively. The MIC profiles differed between P. zopfii genotype 2 and P. blaschkeae , with the latter species being more susceptible to both compounds. The MIC 50 and MIC 90 of IPBC were 4 and 8 mg/L for P. zopfii genotype 2 and 1 and 2 mg/L for P. blaschkeae , respectively. The MIC 50 and MIC 90 of AMB were both 1 mg/L for P. zopfii genotype 2 and 0.25 and 1 mg/L for P. blaschkeae , respectively. Both IPBC and AMB exhibited the ability to kill Prototheca spp. The MAC for 90% of isolates of IPBC was twice the MIC 90 , whereas an 8-fold increase of the MIC 90 was algicidal in the case of AMB. Overall, the combined use of IPBC and AMB exhibited an increased algicidal effect, albeit the fractional inhibitory concentration index showed synergistic activity only against 3 P. zopfii genotype 2 isolates. For all the remaining isolates (87.5%), this combination produced only an additive effect. The MTT assay results showed both IPBC and AMB, at the concentrations employed in the study, to be nontoxic to the epithelial mammary gland cells (cell viability >90%). Notably, only IPBC at the highest concentration (i.e., 8 mg/L) exerted a slight cytotoxic effect on the cell line tested (mean cell viability: 88.54 ± 3.88 and 90.66 ± 3.0, after 2 and 4 h of MTT treatment, respectively). The anti- Prototheca activity of IPBC was here demonstrated for the first time. In addition, the combined use of IPBC with AMB enhanced each other's effect, creating an additive rather than synergistic interaction. Both agents, used at concentrations corresponding to MIC values against Prototheca spp., showed no toxic effect for the mammary epithelial cells. In conclusion, IPBC, used either alone or in combination with AMB, can be considered a promising option in the treatment armamentarium for protothecal mastitis in dairy cows

Effect of climate change on the occurrence of selected infectious diseases

Wprowadzenie i cel pracy. Polska, podobnie jak duża część Europy, leży w strefie klimatu umiarkowanego. Większość danych dotyczących klimatu pochodzi z obserwacji temperatury. Prawdopodobnie wzrost średniej temperatury powietrza będzie coraz bardziej odczuwalny, a tym samym możliwy jest wzrost zapadalności na niektóre choroby zakaźne. Celem pracy jest zaprezentowanie zarysu klimatu Polski, jak również klimatu Europy, przedstawienie zależności między zachodzącymi zmianami klimatycznymi a występowaniem chorób zakaźnych. Skrócony opis stanu wiedzy. W klimacie umiarkowanym najwięcej przypadków zachorowań na choroby układu oddechowego zostaje odnotowywanych podczas zimnych, suchych zim o małym usłonecznieniu. Prawdopodobnie zmiany klimatu mogą stać się poważnym zagrożeniem dla zdrowia na świecie w XXI wieku. Do ważnych czynników środowiskowych wpływających na patogeny są temperatura, opady i wilgotność powietrza. Niektóre choroby zakaźne mają tendencje do cykliczności sezonowej, która może zostać wytłumaczona jako wpływ klimatu. Pomimo trudności w przedstawieniu wpływu klimatu na choroby zakaźne, obserwuje się postępy w ocenie wpływu na nie nieproporcjonalnego zwiększenia temperatury zimą, jak również zwiększonego natężenia i częstości występowania zjawisk pogodowych. Podsumowanie. Klimat zmienia się zarówno w Europie, jak i na całym świecie, prawdopodobnie w niektórych środowiskach te zmiany będą bardziej odczuwalne. Klimat wpływa na środowisko, gospodarza oraz na patogeny. Niektóre choroby zakaźne są bardzo wrażliwe na zmiany klimatu, takie jak temperatura i wilgotność. Konsekwencje zmian klimatu są trudne do ocenienia, ale również nieuniknione, należy się spodziewać, że zmiany klimatu staną się poważnym zagrożeniem dla ludzi.Introduction and objective. Poland, similar to a large part of Europe, lies in the zone of moderate climate, and most of the data concerning climate originates from the observation of temperature. An increase in the mean air temperature will probably be more perceptible and, consequently, an increase in morbidity due to some infectious diseases is possible. The objective of the study is the presentation of an outline of the climate in Poland and Europe, and to demonstrate the relationship between the ongoing climatic changes and infectious diseases. Brief description of the state the knowledge. In moderate climate, the largest number of cases of respiratory diseases are recorded during the occurrence of cold, dry winters with low insolation. In the 21st century, climatic changes will probably become a serious health risk worldwide. Temperature, precipitation and humidity are important environmental factors affecting the pathogens. Some infectious diseases show a tendency towards seasonal cyclical patterns, which may be explained by the effect of climate. Despite difficulties in presenting the impact of climate on infectious diseases, progress takes place in assessment of the effect of disproportionate increase in winter temperatures, increased intensity and frequency of weather phenomena. Summing up. Climate changes are observed both in Europe and worldwide, and probably in some environments these changes will be more perceptible. Climate exerts an effect on the environment, host, and pathogens. Some infectious diseases are very sensitive to changes in climate, such as temperature and humidity. The consequences of climate change are difficult to assess, but also inevitable, and possibly climate change will become a serious threat to humans

Koksowanie węgli niekoksujących się

Tyt. z ekranu tytułowego.Projekt archiwizacji Skryptów Uczelnianych AGH i innych wydawnictw książkowych.Dostępny także w wersji drukowanej.Tryb dostępu: Internet

Tryptophan, Kynurenine and Kynurenic Acid Concentrations in Milk and Serum of Dairy Cows with Prototheca Mastitis

The aim of this work was to investigate serum and milk levels of tryptophan (TRP), kynurenine (KYN), and kynurenic acid (KYNA), as well as the activity of indoleamine 2,3-dioxygenase (IDO) in cows with mastitis due to Prototheca algae. The study was prompted by previous research showing a link between the KYN pathway of TRP metabolism and bovine mastitis of bacterial etiology. The study was carried out over a 2-year period (2018–2019) and included quarter milk and serum samples collected from six dairy herds in Poland. The samples were obtained from healthy cows and cows with Prototheca mastitis of either clinical and subclinical manifestation, as determined upon direct measurement of the somatic cell count or indirectly by performing a California Mastitis Test on suspected quarters. Both TRP and KYN concentrations were significantly lower in milk of mastitic cows compared to healthy animals (0.8 vs. 8.72 µM, p = 0.001; 0.07 vs. 0.32 µM, p = 0.001, respectively). The difference in TRP and KYN concentrations in the sera of the two animal groups was much less pronounced (25.55 vs. 27.57 µM, 3.03 vs. 3.56 nM, respectively). The concentration of KYNA was almost at the same level in milk (1.73 vs. 1.70 nM) and in serum (80.47 vs. 75.48 nM) of both mastitic and healthy cows. The data showed that the level of TRP and its metabolites in serum was conspicuously higher compared to milk in all cows under the study. The activity of IDO was significantly higher in milk of cows with Prototheca mastitis compared to healthy animals (71.4 vs. 40.86, p < 0.05), while in serum it was pretty much the same (135.94 vs. 124.98, p > 0.05). The IDO activity differed significantly between serum and milk both for mastitic (135.94 vs. 71.4, p < 0.05) and healthy cows (124.98 vs. 40.86, p < 0.001). In conclusion, low values of TRP and KYN concentrations or elevated IDO activity in milk samples might be used as markers of mastitis due to infectious causes, including Prototheca spp