Innovative aspects of dog training in high explosives detection

Psi nos jest nieocenioną pomocą dla ludzkości dzięki jego znakomitej czułości i zdolności do rozpoznawania oraz rozróżniania zapachów, tj. substancji lotnych wydzielanych przez dany materiał. W zestawieniu z coraz bardziej zaawansowaną technologią urządzeń elektronicznych do detekcji nadal zajmuje pierwsze miejsce na „podium”. Dzięki takim zdolnościom pies jest świetnym wsparciem w walce z terroryzmem, gdzie wczesne wykrycie materiałów wybuchowych (MW) odgrywa kluczową rolę dla bezpieczeństwa. W szkoleniu psów do wykrywania materiałów wybuchowych w polskich służbach mundurowych wykorzystuje się rzeczywiste próbki materiałów wybuchowych. Badania na arenie międzynarodowej wykazały jednak, że takie podejście nie daje stuprocentowej gwarancji wykrycia MW przez psa. Dodatkowo stosowanie klasycznych próbek MW w szkoleniu jest obarczone zarówno ryzykiem związanym z bezpieczeństwem przewodnika oraz psa, jak i z prawnymi restrykcjami podczas przechowywania, używania i transportu. Innowacyjne rozwiązanie wypracowane podczas realizacji tematu „Referencyjny zestaw próbek materiałów wybuchowych do szkolenia i atestacji psów służbowych” pozwala na większą swobodę manipulacji próbką szkoleniową, zwiększa bezpieczeństwo użytkowania i w rzeczywistości daje większą gwarancję wykrycia materiału wybuchowego przez psa.A nose of a dog is an invaluable help to humanity thanks to its excellent sensitivity and ability to recognize and distinguish odours, i.e. volatile substances emitted by a given material. In comparison with the increasingly advanced technology of electronic detection devices, it still ranks first on the “podium”. Due to its special abilities the dog is a great support in the fight against terrorism, where the early detection of explosives plays a key role in security. In the training process of a dog for the detection of explosives in Polish uniformed services genuine explosives samples are used. However, international studies have shown that this approach does not give 100% guarantee of HE detection by a dog. In addition, the use of classic HE samples in training involves a risk associated to the safety of both the operator and the dog and is burdened by law enforcement restrictions related to storage, use and transportation. An innovative solution developed during the implementation of the subject “Reference set of explosives samples for training and validation of service dogs” allows for more flexibility while handling the sample, increases the safety of use and provides a better detection of the explosive by the dog

Selenium-Containing Exopolysaccharides Isolated from the Culture Medium of <i>Lentinula edodes</i>: Structure and Biological Activity

In continuation of our research on the influence of selenium incorporation on the biosynthesis, structure, and immunomodulatory and antioxidant activities of polysaccharides of fungal origin, we have isolated from a post-culture medium of Lentinula edodes a selenium (Se)-containing exopolysaccharide fraction composed mainly of a highly branched 1-6-α-mannoprotein of molecular weight 4.5 × 106 Da, with 15% protein component. The structure of this fraction resembled mannoproteins isolated from yeast and other mushroom cultures, but it was characterized by a significantly higher molecular weight. X-ray absorption fine structure spectral analysis in the near edge region (XANES) suggested that selenium in the Se-exopolysaccharide structure was present mainly at the IV oxidation state. The simulation analysis in the EXAFS region suggested the presence of two oxygen atoms in the region surrounding the selenium. On the grounds of our previous studies, we hypothesized that selenium-enriched exopolysaccharides would possess higher biological activity than the non-Se-enriched reference fraction. To perform structure–activity studies, we conducted the same tests of biological activity as for previously obtained mycelial Se-polyglucans. The Se-enriched exopolysaccharide fraction significantly enhanced cell viability when incubated with normal (human umbilical vein endothelial cells (HUVEC)) cells (but this effect was absent for malignant human cervical HeLa cells) and this fraction also protected the cells from oxidative stress conditions. The results of tests on the proliferation of human peripheral blood mononuclear cells suggested a selective immunosuppressive activity, like previously tested Se-polyglucans isolated from L. edodes mycelium. The Se-exopolysaccharide fraction, in concentrations of 10–100 µg/mL, inhibited human T lymphocyte proliferation induced by mitogens, without significant effects on B lymphocytes. As with previously obtained Se-polyglucans, in the currently tested Se-polymannans, the selenium content increased the biological activity. However, the activity of selenium exopolysaccharides in all tests was significantly lower than that of previously tested mycelial isolates, most likely due to a different mode of selenium binding and its higher degree of oxidation