Rickettsia spp. in Ticks, Poland

Ticks are recognized as the main vectors and reservoirs of spotted fever group rickettsiae. We searched for the most prevalent Rickettsia spp. in Poland and found R. slovaca and R. helvetica bacteria in ticks in southern and central Poland; R. raoulti was found in ticks in all parts of Poland

Investigating the persistence of tick-borne pathogens via the R0 model

In the epidemiology of infectious diseases, the basic reproduction number,R0, has a number of important applications, most notably it can be used to predict whether a pathogen is likely to become established, or persist, in a given area. We used the R0 model to investigate the persistence of 3 tick-borne pathogens; Babesia microti, Anaplasma phagocytophilum and Borrelia burgdorferi sensu lato in an Apodemus sylvaticus-Ixodes ricinus system. The persistence of these pathogens was also determined empirically by screening questing ticks and wood mice by PCR. All 3 pathogens behaved differently in response to changes in the proportion of transmission hosts on which I. ricinus fed, the efficiency of transmission between the host and ticks and the abundance of larval and nymphal ticks found on small mammals. Empirical data supported theoretical predictions of the R0 model. The transmission pathway employed and the duration of systemic infection were also identified as important factors responsible for establishment or persistence of tick-borne pathogens in a given tick-host system. The current study demonstrates how the R0 model can be put to practical use to investigate factors affecting tick-borne pathogen persistence, which has important implications for animal and human health worldwide

Rickettsiaceae and Anaplasmataceae infections in Ixodes ricinus ticks from urban and natural forested areas of Poland

BACKGROUND: Ixodes ricinus is a major vector for a range of microbial pathogens and the most prevalent and widely distributed tick species on the European continent, occurring in both natural and urban habitats. Nevertheless, little is known about the relative density of ticks in these two ecologically distinct habitats and the diversity of tick-borne pathogens that they carry. METHODS: We compared densities of questing I. ricinus nymphs and adults in urban and natural habitats in Central and Northeastern Poland, assessed the prevalence and rate of co-infection with A. phagocytophilum, Rickettsia, Ehrlichia and ‘Ca. Neoehrlichia spp.’ in ticks, and compared the diversity of tick-borne pathogens using molecular assays (PCR). RESULTS: Of the 1325 adults and nymphs, 6.2% were infected with at least one pathogen, with 4.4%, 1.7% and less than 0.5% being positive for the DNA of Rickettsia spp., A. phagocytophilum, Ehrlichia spp. and Ca. N. mikurensis, respectively. Although tick abundance was higher in natural habitats, the prevalence of the majority of pathogens was higher in urban forested areas. CONCLUSION: We conclude that: (i) zoonotic genetic variants of A. phagocytophilum are widely distributed in the Polish tick population, (ii) although the diversity of tick borne pathogens was higher in natural habitats, zoonotic species/strains were detected only in urban forests, (iii) and we provide the first description of Ca. N. mikurensis infections in ticks in Poland

A Bayesian Model of Group Decision-Making

A change in the opinion of a group, treated as a network of communicating agents, caused by the accumulation of new information is expected to depend on communication within the group, cooperation and, possibly, a kind of conformity mechanism. We have developed a mathematical model of the creation of a group decision, including this effect. This is based on a Bayesian description of inference and can be used for both conscious and inattentive acts. This model can be used to study the effect of whether a leader exists or not and other group inhomogeneities, as well as establishing the (statistical) significance and quality of a group decision. The proposed evolution equations explain in a straightforward, analytical way some general properties of the general phenomenon of conformity (groupthink). To illustrate this theoretical idea in practice, we created an information technology (IT) tool to study the effect of conformity in a small group. As an example, we present results of an experiment performed using a network of students' tablets, which could not only measure group pressure, but also conduct and control collaborative thinking in the group. (original abstract

Sodium-glucose co-transporter-2 (SGLT2) inhibitors: novel oral antidiabetic drugs

Wstęp. Wzrastająca zapadalność na cukrzycę, szczególnie typu 2, i niedostateczne możliwości jej wyrównania metabolicznego wymuszają intensyfikację leczenia i poszukiwanie nowych opcji terapeutycznych, wpływających na kolejne szlaki zaburzeń metabolicznychw cukrzycy.Materiał i metody. Jako jeden z potencjalnych celów terapeutycznych wymienia się zwiększoną reabsorpcję glukozy z moczu u chorych na cukrzycę typu 2.Wyniki. Nową grupą leków modyfikującą ten patomechanizm cukrzycy są inhibitory kotransportera glukozowo-sodowego 2 (SGLT2). Wspomniane symportery zlokalizowane w cewkach bliższych nefronu są odpowiedzialne za resorpcję około 90% glukozy z moczu.Wnioski. Blokada tego układu transportującego prowadzi do glukozurii i obniżenia glikemii. Poza obniżaniem glikemii inhibitory SGLT2 powodują też redukcję masy ciała i ciśnienia tętniczego. Najczęstszymi działaniami niepożądanymi inhibitorów SGLT2 są zakażenia układu moczowo-płciowego, szczególnie grzybicze. Wieloletnie obserwacje chorych na rodzinną glukozurię nerkową (FRG), spowodowaną genetycznym defektem SGLT2, nie wykazały istotnych patologii spowodowanych utrzymującą się glukozurią.Introduction. Due to rising diabetes mellitus morbidity and inadequate glycemic control new therapeutic agents, targeting on different metabolic pathways, need to be developed.Materials and methods. Gained renal glucose reuptake in patients with diabetes mellitus is one of the target.Results. Sodium-glucose co-transporter-2 (SGLT2) inhibitors are able to affect this mechanism. SGLT2 localized in proximal renal tube are responsible for reuptake of 90% of glucose from the urine.Conclusions. Inhibition of this transporting system induces glucosuria and decreases blood glucose level. Additionally SGLT2 inhibitors lead to body mass reduction and lower blood pressure. Most frequent adverse effects are genitourinary infections, particularly fungal. Long-term follow-up of patients with familial renal glucosuria (FRG), caused by genetic defect of SGLT2, has not revealed major abnormalities due to prolonged glucosuria

Spectroscopy of high-energy states of lanthanide ions

We discuss recent progress and future prospects for the analysis of the 4f${N-1}$5d excited states of lanthanide ions in host materials. Ab-initio calculations for Ce$^{3+}$ in LiYF$_4$ are used to estimate crystal-field and spin-orbit parameters for the 4f$^1$ and 5d$^1$ configurations. We discuss the possibility of using excited-state absorption to probe the electronic and geometric structure of the 4f$^{N-1}$5d excited states in more detail and we illustrate these ideas with calculations for Yb$^{2+}$ ions in SrCl$_2$

Release of coumarin encapsulated in chitosan-gelatin irradiated films

Chitosan and fish gelatin were used to formulate active biobased films containing an antioxidant (coumarin). After drying, the films were irradiated at 40 and 60 kGy using an electron beam accelerator. The effect of irradiation on the film properties as well as the coumarin release mechanism were investigated and compared with the control. Electron Spin Resonance (ESR) revealed free radical formation during irradiation in films containing coumarin. Antioxidant addition and/or irradiation treatment at a dose of 60 kGy resulted in a shift of amide A and amide B peaks. Furthermore a shift of amide II band was only observed for the control film at the same dose. Irradiation allowed improving the thermal stability of the control films. Both irradiation process and addition of coumarin increased the surface wettability (increase of the polar component of the surface tension). From the water barrier analysis, neither irradiation nor coumarin addition influenced the permeability at the lower RH gradient used (0e30% RH). Using the higher RH gradient (30e84%) induced a rise of the WVP of all films (containing or not coumarin) after irradiation treatment. At 60 kGy, the tensile strength of only the control films increased significantly. Considering coumarin release from the film in aqueous medium, the apparent diffusion coefficient of coumarin is two times reduced after irradiation. Irradiation also allowed to better protect the incorporated antioxidant. Indeed, the amount of coumarin in the non-irradiated film was significantly lowered compared to the initial quantity, which is probably due to chemical reactivity