Invasive alien plants affect grassland ant communities, colony size and foraging behaviour

Ants are dominant members of many terrestrial ecosystems and are regarded as indicators of environmental changes. However, little is known about the effects of invasive alien plants on ant populations, particularly as regards the density, spatial distribution and size of ant colonies, as well as their foraging behaviour. We addressed these questions in a study of grassland ant communities on five grasslands invaded by alien goldenrods (Solidago sp.) and on five non-invaded grasslands without this plant. In each grassland, seven 100 m plots were selected and the ant colonies counted. Ant species richness and colony density was lower in the plots on the invaded grasslands. Moreover, both of these traits were higher in the plots near the grassland edge and with a higher number of plant species in the grasslands invaded by goldenrods but not in the non-invaded ones. On average, ant colony size was lower on the invaded grasslands than the non-invaded ones. Also, ant workers travelled for longer distances to collect food items in the invaded areas than they did in the non-invaded ones, even after the experimental removal of some ant colonies in order to exclude the effect of higher colony density in the latter. Our results indicate that invasive alien goldenrods have a profound negative effect on grassland ant communities which may lead to a cascade effect on the whole grassland ecosystem through modification of the interactions among species. The invasion diminishes a major index of the fitness of ants, which is a colony's size, and probably leads to increased foraging effort of workers. This, in turn, may have important consequences for the division of labour and reproductive strategies within ant colonies

Investigation of starch hydration by 2D time domain NMR

Proton exchange between spin groups of the solid matrix of hydrated granular potato starch and water was studied using the 2D time domain NMR. The proton spin-spin relaxation time T$\text{}_{2}$, and spin-lattice relaxation time T$\text{}_{1}$ (selective and non-selective pulse sequences) were measured at room temperature. The observed spin relaxation results were analysed for exchange assuming a two-site exchange model (between water and solid matrix of starch). In this analysis we determined the intrinsic spin-lattice relaxation time for water protons (49 ms) and solid starch matrix protons (172 ms), as well as the water-starch magnetization exchange rate (86 s$\text{}^{-1}$)

Anti-Müllerian hormone dynamics during ovulation induction treatment with recombinant follicle-stimulating hormone in women with polycystic ovary syndrome

Wstęp: Hormon anty-Müllerowski (AMH) jest uznawany za marker odpowiedzi jajników na stymulację owulacji. Materiał i metody: Do badania włączono 26 kobiet pragnących zajść w ciążę i wykazujących oporność na leczenie cytrynianem klomifenu. Wszystkie pacjentki były stymulowane rekombinowaną folitropiną. Wyniki: W grupie dobrze odpowiadającej na stymulację stężenia lutropiny i estradiolu były niższe niż w grupie nieodpowiadającej. Stężenie wolnego testosteronu, indeks wolnych androgenów i insulinooporność były większe w grupie nieodpowiadającej na stymulację. W grupie odpowiadającej stężenie AMH obniżyło się w kolejnych dniach stymulacji i spadek ten był wyraźniejszy u pacejntek z większą liczbą wzrastających pęcherzyków. Pacjentki z PCOS wykazują niskie stężenia FSH i wysokie AMH. Uważa się, że obniżenie stężenia AMH poprzedza wzrost pęcherzyków w trakcie stymulacji rekombinowanym FSH. U bezowulacyjnych pacjentek z PCOS łagodny wzrost w surowicy FSH hamuje AMH, odblokowując ekspresję aromatazy przez wybrane pęcherzyki, co pozwala na wyłonienie rosnących pęcherzyków. Kobiety z nasilonym hiperandrogenizmem, insulinoopornością i wysokim poziomem LH nie odpowiadają na stymulację. Wnioski: Obniżenie stężenia AMH u pacjentek z PCOS po tygodniu stymulacji rekombinowanym FSH jest praktycznym, cennym markerem pozwalającym wyłonić pacjentki z wysokim ryzykiem zespołu hiperstymulacji. Bezowulacyjne pacjentki z PCOS z ciężkim hiperandrogenizmem, insulinoopornością i hiperinsulinemią nie powinny być kwalifikowane do stymulacji owulacji rekombinowanym FSH. (Endokrynol Pol 2013; 64 (3): 203–207)Introduction: Anti-Müllerian hormone (AMH) has been suggested as a predictor of ovarian response to ovulation induction and controlled ovarian hyperstimulation. Material and methods: Twenty-six women, wishing to become pregnant and who showed resistance to clomiphene citrate, were included in the study. All women received recombinant follicle-stimulating hormone (recFSH). Results: In the group of good responders, luteinising hormone (LH) and oestradiol levels were lower than in the group of non-responders. Free testosterone levels, free androgen index, and insulin resistance were higher in the group of non-responders. In the group of good responders, AMH levels decreased on successive days of ovarian stimulation and a greater slope of AMH levels was observed in patients with a higher number of increasing follicles. PCOS patients have low FSH and high AMH levels. It could be suggested that the serum AMH decrease preceded growth of many follicles, which is a consequence of the FSH stimulation. In anovulatory PCOS women, gently increasing the serum FSH level reduces the AMH excess, thus relieving the inhibition from the latter on aromatase expression by selectable follicles and allowing the emergence of growing follicles. Patients with severe hyperandrogenism, insulin resistance and high level of LH do not respond to stimulation. Conclusions: The decrease of AMH levels in PCOS women after one week of ovarian stimulation is a practical, valuable indicator which could predict the patients with a high risk of ovarian hyperstimulation. Anovulating PCOS patients with severe hyperandrogenism, insulin resistance and hyperinsulinaemia should not be qualified for recFSH ovarian stimulation. (Endokrynol Pol 2013; 64 (3): 203–207

Could fungal infection make ant societies more open?

Ant colonies are a highly rewarding target for many pathogens and parasites and they also host various species of social parasites that exploit their social system. Myrmica ants seem to be particularly susceptible to exploitation by social parasites and by ecto- and endoparasites. Also many Myrmica colonies frequently adopt unrelated gynes, which can be interpreted as temporary social parasites. Myrmica scabrinodis is a common host of the ectoparasitic fungus Rickia wasmannii and its colonies are used by socially parasitic butterfly larvae of Maculinea genus. In some M. scabrinodis populations both R. wasmannii and Maculinea butterflies occur together using the same host colonies. In our study we used such population to check whether fungal infection change the threshold of acceptance of social parasites and unrelated queens by ants and make colonies more open for strangers. For this purpose we performed experiments during which we tested how infection by R. wasmannii affects frequency and time of Maculinea larva adoption and adoption of unrelated ant queens. We also carried out aggression tests where we used M. scabrinodis workers originating from infected and uninfected colonies to check if fungal infection influences the amount of adverse reactions. Our preliminary results indicate that ants infected by the fungus are more readily adopting social parasites, while being less aggressive towards foreign queens. Thus, infected colonies could be more prone for social parasitism

Morphology of caterpillars and pupae of European Maculinea species (Lepidoptera: Lycaenidae) with an identification table

Ofthe four recognized Maculinea species that occur in Europe, three (M. teleius, M. nausitlzous, and M. alcon) are found on damp meadows, and may co-occur; sometimes their larval instars even occupy the same host ant nest. It is, therefore, important to be able to distinguish between the caterpillars of these species for effective conservation. We present the morphology of the larvae and pupae of these three species, and a simple key to their identification. Inter-specific differences among larvae and pupae, and within-species differences among larval instars, are underlined in order to enable their proper identification. The length, colour and distribution of bristles are considered the best features for species and instar identification. The morphology ofthe described species is compared with that of the other European species, M. arion

Local populations of endangered Maculinea (Phengaris) butterflies are flood resistant

Semi-natural wet meadows are threatened by drainage, the abandonment of traditional management and climate change. The large blue butterflies Maculinea teleius and M. nausithous are flagship species associated with wet meadows and are the targets of many conservation programmes. However, there is little knowledge on the impact of natural catastrophes, such as floods, on the persistence of these butterflies. In our study we tested how a flood that resulted in the temporary inundation of meadows affected populations of M. teleius and M. nausithous. Studies were conducted in two consecutive seasons of 2009 (with ‘normal’ weather) and 2010 (with extreme rainfall and a consequent flood in May) in a wet meadow complex located in the Vistula River valley in southern Poland. In both years the abundance of adults was estimated for each local habitat patch (n = 55) within sympatric metapopulations of both species. Additionally, in June 2010, i.e. directly after the flood and shortly before the flight period, a total of 754 Myrmica ant nests in 10 habitat patches (6 inundated vs. 4 not inundated) were checked for the presence of Maculinea larvae and pupae. We found no impact of inundation on year-to-year changes in adult population sizes. The probability of occurrence of Maculinea larvae and pupae in ant nests was higher in temporarily inundated meadows. Our results indicate that temporary inundation occurring after long-term downpours does not negatively affect the investigated species even during the larval period in ant nests at ground level. This provides an argument against drainage works in wet meadows with Maculinea butterflies

Podaż węglowodanów w diecie i kontrola glikemii u pacjentów leczonych za pomocą mieszanek insuliny ludzkiej

Wstęp. Leczenie mieszankami insuliny ludzkiej (PMHI, pre-mixed human insulin) jest na całym świecie jednym z najpopularniejszych modeli insulinoterapii. Jednak osiągnięcie dobrej kontroli glikemii u osób stosujących PMHI może być trudne, głównie ze względu na zmienne spożycie węglowodanów i podaż kalorii. Badanie przeprowadzono w celu oceny wpływu modyfikacji diety na stężenia glukozy u chorych na cukrzycę typu 2 (T2DM, type 2 diabetes mellitus) stosujących PMHI. Materiał i metody. Do tego prospektywnego badania przeprowadzonego w układzie naprzemiennym włączono 8 chorych na T2DM leczonych PMHI (średnie stężenie HbA1c 8,4%). U chorych zastosowano 2 diety, obie cechujące się stałą zawartością kalorii/węglowodanów: dieta A - 50% kalorii pochodzi z węglowodanów, 30% - z tłuszczów, 20% - z białek; dieta B - 40% kalorii pochodzi z węglowodanów, 30% - z tłuszczów i 30% - z protein. Badanie prowadzono w warunkach domowych, dostarczano chorym wszystkie posiłki. Każdy chory stosował dietę A przez 9 dni, a następnie po 7-dniowym okresie wypłukiwania przez 9 dni stosował dietę B. Profile glukozy oceniano przy użyciu systemu ciągłego monitorowania glikemii (CGMS, continuous glucose monitoring system, iPro, Medtronic, USA). Wyniki. Zmiana z diety A na dietę B spowodowała zmniejszenie średnich stężeń glukozy (dane z system CGMS) ze 145 mg/dl do 133 mg/dl (p = 0,0001), redukcję SD z 51 do 42 mg/dl (p = 0,0429) oraz skrócenie czasu, w którym glikemia utrzymywała się powyżej progowej wartości 180 mg/dl z 18% do 11% (p = 0,0006). Wnioski. W badaniu wykazano, że zapewnienie odpowiedniej i powtarzalnej podaży węglowodanów i kalorii z umiarkowanym ograniczeniem węglowodanów umożliwia poprawę kontroli glikemii u chorych na cukrzycę typu 2.Introduction. The treatment with pre-mixed human insulins (PMHI) is globally one of the most popular models of insulin therapy. Achieving good glycaemic control on PMHI may, however, be difficult, mostly due to inconsistent calorie and carbohydrate intake. The aim of the study was to examine the impact of dietary modification on glucose levels in patients with type 2 diabetes mellitus (T2DM) treated with PMHI. Materials and methods. In this prospective cross-over analysis we studied 8 T2DM PMHI treated individuals (mean HbA1c 8.4%). We exposed patients to 2 diets, both based on steady calorie/carbohydrate content: "A" - 50% calories from carbohydrates, 30% from fat, 20% from protein, "B" - 40% from carbohydrates, 30% from fat and 30% from protein. The study was performed in home settings, all the meals were delivered to the patients. Each patient was exposed to diet A for 9 days, than after 7 days of wash-out to 9 days of diet B. Glucose patterns were assessed with continuous glucose monitoring system (CGMS, iPro, Medtronic, USA). Results. Switching from diet A to diet B resulted in a decrease in mean glucose levels (CGMS data) from 145 mg/dL to 133 mg/dL (p = 0.0001), SD reduction from 51 to 42 mg/dL (p = 0.0429), and a decrease in time spent above the target of 180 mg/dL from 18% to 11% (p = 0.0006). Conclusions. The study demonstrates that consistent and repeatable carbohydrate (CH) and calorie intake with moderate restriction of CHs helps to improve glycaemic control in this group of patients