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Recent advances in the design and application of redox-active fluorescent proteins (FPs) stimulated an interest in the electronic structure of the ionized/electron-detached FP chromophores. Here, we report the results of a computational study of the electron-detached and ionized states of model chromophores of green and red FPs. We focus on the analysis of the effects of the phenolate OH group position (ortho, meta, and para) on relative energies of the chromophores in the ground as well as in the ionized/detached electronic states. We found that, similarly to the green chromophore, the red chromophores with the OH group in meta position have lower vertical detachment energies (DE) and greater ionization energies relative to the ortho and para forms. Moreover, the effect is stronger for the red anionic chromophores. The differences in DE in meta species relative to their para counterparts are 0.47 and 0.25 eV for the red and green chromophores, respectively. The observed trends are due to a combined effect of resonance stabilization and the electronegativity of the acylimine group in the red chromophores. The analysis is supported by the computed charge and spin density delocalization patterns. V C 2014 Wiley Periodicals, Inc.

Nanoporous alumina films (NPAF) have been elaborated by anodization of an aluminum film on silicon wafer. Ex situ structural characterization of the films has been achieved with grazing incidence small angle X-ray scattering under ultra high vacuum atmosphere and using a synchrotron source. The comparison of the experimental patterns with suitable modeling confirms the cylindrical geometry of the pores well as the good local hexagonal order. (C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

The effect of the relative humidity (RH) of the environment on water loss is studied in Triatoma brasiliensis. Starved or recently fed early stages of T. brasiliensis are exposed to 15, 37, 46 and 73% RH. Water loss is estimated by weighing individual insects daily. The results obtained with starved insects show that the group maintained at 15% RH loses more water and shows a higher mortality compared with the others. An experiment in which recently fed nymphs are exposed to different RHs shows that all groups of insects lose the greatest amount of water during the first day. The group exposed to 15% RH show a higher water loss than the others before and after ecdysis. The survival of recently fed nymphs is not affected by the level of RH to which they are exposed. The results are discussed in relation to the water balance in this species.

The effects of temperature on the development of early stages and the thermopreference of nymphs and adults were analysed in the haematophagous bug Triatoma brasiliensis Neiva, 1911 (Hemiptera, Reduviidae). Egg hatching, mortality of nymphs, feeding and moulting success of the early stages of T. brasiliensis were all affected by temperature. While high rates of egg hatching were observed between 25 and 27 °C, no hatching occurred at 12, 19 and 38 °C. The mortality of first-instar nymphs was highest at 38 °C, at which no insects survived after 10 days of exposure. Feeding success was only affected at the lowest temperature (12 °C). No ecdysis was observed in the groups exposed to 12, 19 and 21 °C. Recently fed fourth-instar nymphs preferred to stay at a temperature of approximately 30 °C. The preferred temperature began to decline gradually to approximately 27 °C during ecdysis, reaching 26 °C at 30 days after ecdysis. After a second blood meal, the insects' preferred temperature was again approximately 30 °C. The thermopreference pattern of females was similar to that of nymphs. Nymphs and females showed a daily fluctuation in their preferred temperature, moving towards higher values at the beginning of the dark phase, and choosing lower ones after this time interval, at which they remained until the end of the light phase. The females laid their eggs in all sectors of the arena, although the largest numbers of eggs were found between 28 and 32 °C.

The response of Triatoma infestans (Klug) to odours left behind by walking insects was analysed. The insects aggregated on papers marked with putative chemical footprints in the absence of other assembling chemical signals. Contact of the receptor insect with the treated surface was necessary to elicit the response because the signal was not able to attract insects, only to arrest them on marked surfaces. These requirements contrast with other chemical aggregation signals of triatomines that attract the insect and involve olfactory responses. By washing the cuticle of the insects with hexane and impregnating papers with the extract, a response was evoked in test insects similar to that elicited by papers on which insects had walked. The biological role of this novel aggregation factor is discussed in relation to other assembling signals of different origin.

The projections of first-order ocellar interneurons were analyzed in the hematophagous bug Triatoma infestans by cobalt filling. The axons run between the calyces of the mushroom bodies and dorsal of the central body to different regions of the brain and the subesophageal and thoracic ganglia. The interneurons can be grouped into large L cells and small S cells. The L cells have cell bodies ranging from 11.5 to 25 μm and axons ranging from 8 to 25 μm diameter (measured in the ocellar nerve); the S cells have smaller cell bodies of 9 μm or less and axon diameters less than 5 μm. The projections of ten L cells are described in detail; they project to the protocerebral posterior slope (PS), the other ocellus (O), the optic neuropile, and the subesophageal, pro-, meso-, and metathoracic ganglia, either to ipsi- (PS I, II), or contra- (PS IV, V), or bilateral areas. In this case projections occur to the same areas (PSO, PS III) or different areas at each side (PSOE; E = eye). Large-descending (LD) first-order interneurons project to the contralateral posterior slope of the protocerebrum, the deutocerebrum, and subesophageal, pro-, mesa-, and metathoracic areas (LD I-III). Cell bodies are located in the dorsal protocerebral lobes and pars intercerebralis, except the PS II neuron and three LD cells, which are located in the ipsilateral posterior protocerebrum. This is the first report about ocellar pathways in Hemiptera. Their adaptive function is discussed with reference to the bugs' behavior as Chagas disease vectors. © 1996 Wiley-Liss, Inc.

The effect of the addition of egg yolk to a blood meal on the development of Triatoma infestans (Klug) was analysed. Egg yolk was added in different quantities to heparinized, citrated or defibrinated bovine blood, which was offered in an artificial feeder. Control groups were fed on either non-supplemented blood or hen in vivo. Results indicated that the addition of egg yolk to a blood meal reduced the intermoult interval and the moult success increased when egg yolk was added to the diet. The effect was more dramatic for the less suitable diets, as follows: citrated blood > defibrinated blood > heparinized blood. The minimal and most effective concentration of egg yolk in the diet was 10% v/v. When the egg yolk was centrifuged in a density-gradient, fractions with different performance could be obtained; middleweight fractions, but not the heaviest or lightest ones reproduced the observed effects of the whole yolk at the corresponding concentration. Growth rate and moulting success showed to be differentially affected by the diets and the growth performance of in vivo-fed experimental groups could be completely reproduced by adding yolk to the blood diets offered in artificial feeders.

A total of 3783 subjects were enrolled to compare IgA and IgG gliadin antibodies (AGA) with IgA endomysium antibodies (EMA) in coeliac disease (CD). Among 688 children with untreated CD EMA were positive in 93.8%, IgA AGA in 84.9% and IgG AGA in 90.2%. AGA, but not EMA, sensitivity decreased with age. EMA were present in 3.8% of control subjects, IgA AGA in 14.9% and IgG AGA in 34.3%. Follow-up of 5 of 39 EMA-positive controls showed flat mucosa. Combined determination of EMA and AGA showed an increased predictive value: if EMA and AGA were both positive, the mucosa was flat in 99.1%, if both were negative, the mucosa was normal in 99.1%. After a gluten-free diet (GFD), IgA-AGA disappeared first. Among 21 patients not on a strict GFD and in 194 coeliac patients after challenge, EMA, but not AGA, were always positive. Among 67 first-degree relatives of coeliacs, the positive predictive value of EMA was 90.6%, IgA AGA 74.3% and IgG AGA 44.6%. In conclusion, EMA screening is an excellent test for the diagnosis and follow-up of CD, and for identification of its silent and latent forms.

The gorging response of 3rd-instar nymphs of the vector of Chagas' disease Triatoma infestans Klug to different diets was analysed using an artificial feeder which allows one to feed a great number of bugs simultaneously. Citrated blood was more acceptable than heparinated blood, either stored at 4°C or at –20°C. Freezing of blood at –20°C and their subsequent haemolysis did not affect the intake of citrated blood when it was defrosted immediately before the experiment, but in fact when this occurred 36 hs before. The addition of mice odours to the artificial feeder did not improve the reaction of the bugs to the food it offer. Saline solutions without phagostimulants proved to evoke gorging. Zusammenfassung Die Zucht von Triatoma infestans King (Het., Reduviidae) ohne lebendes Wirtstier. I. Einflusse auf die aufgenommene Futtermenge Es wurde die Blutaufnahme von Nymphen im 3. Stadium von Triatoma infestans, dem Ubertrager der Chagas-Krankheit, untersucht. Geboten wurden verschiedene Diaten in einer kunstlichen Futterquelle, die die gleichzeitige Futterung einer grosen Anzahl von Wanzen ermoglichte. Bei 4°C als auch bei –20 °C konserviertes Citratblut wurde besser akzeptiert als Heparinblut. Die Konservierung des Blutes bei –20°C (d. h. Hamolysis) hat die Akzeptanz des Blutes dann nicht beeinflust, wenn es kurz vor der Futterung aufgetaut wurde. Lag der Auftauzeitpunkt langer zuruck (36 h) wurde von den Tieren weniger Blut aufgenommen. Der Zusatz von Duft von Mausen an der Futterquelle verbesserte die Aufnahme nicht. Die Tiere nahmen auch reine Salzlosungen ohne Phagostimulantien auf.