Reactive oxygen and nitrogen species are involved in sorbitol-induced apoptosis of human erithroleukaemia cells K562

In this study, we found that production of both reactive oxygen (ROS) and nitrogen (RNS) species is a very early event related to treatment with hyperosmotic concentration of sorbitol. The production of nitric oxide (NO) was paralleled by the increase of the mRNA and protein level of the inducible form of the nitric oxide synthase (iNOS). ROS and RNS enhancement, process concomitant to the failure of mitochondrial trans-membrane potential (ΔΨ), was necessary for the induction of apoptosis as demonstrated by the protection against sorbitol-mediated toxicity observed after treatment with ROS scavengers or NOS inhibitors. The synergistic action of ROS and RNS was finally demonstrated by pre-treatment with rosmarinic acid that, by powerfully buffering both these species, prevents impairment of ΔΨ and cell death. Overall results suggest that the occurrence of apoptosis upon sorbitol treatment is an event mediated by oxidative/nitrosative stress rather than a canonical hyperosmotic shock.     

Germination and pH of intracellular compartments in seeds of Phacelia tanacetifolia

³¹ P nuclear magnetic resonance spectroscope (NMR) was used to study the response of Phacelia tanacetifolia seeds to dark and light conditions during the first 72 h of incubation. Changes in the chemical shifts (δ) of the pH-dependent ³¹P-NMR signals from the vacuolar and the cytoplasmic orthophosphate pools were correlated with the different incubation conditions. In the dark (favorable to germination), the cytoplasmic pH remained nearly constant over the whole period considered, while the vacuolar pH shitted to more acidic values after the 24th h of incubation. In the light (inhibiting germination), the values of cytoplasmic pH tended to become more acidic than in the dark after the 24th h of incubation, while the vacuolar pH remained practically constant. When seed germination was inhibited in the dark by butyric acid (BA). a permeant weak acid, the values of cytoplasmic and vacuolar pH were similar to those of the ungerminated seeds incubated in the light. When, vice versa, seed germination was promoted in the light by fusicoccin (FC), the values of cytoplasmic and vacuolar pH were similar to those of the dark-germinated seeds. A progressive augmentation of P, metabolism occurred both in the dark and in the light up to the 24th h of incubation. Subsequently, light blocked any further evolution of this parameter. Treatment with butyric acid in the dark again mimicked the effect of light, while FC reversed the negative effect of light. The data show that in Phacelia tanacetifolia seeds germination is linked to a more alkaline cytoplasmic pH. The finding that the light-dependent metabolic inhibition occurs after an early activation of metabolism, i.e. after the first 24 h. suggests that the effects of light on the cytoplasmic and vacuolar pH depend on the early metabolic processes involved in the control of the homeostasis of cell pH and/or on the inhibition of the reactivation of the transport mechanisms.     

Suitability of Sludge Biotic Index (SBI), Sludge Index (SI) and filamentous bacteria analysis for assessing activated sludge process performance: the case of piggery slaughterhouse wastewater

Piggery slaughterhouse wastewater poses serious issues in terms of disposal feasibility and environmental impact, due to its huge organic load and variability. It is commonly treated by means of activated sludge processes, whose performance, in case of municipal wastewater, can be monitored by means of specific analyses, such as Sludge Biotic Index (SBI), Sludge Index (SI) and floc and filamentous bacteria observation. Therefore, this paper was aimed at assessing the applicability of these techniques to piggery slaughterhouse sewage. A plant located in Northern Italy was monitored for 1 year. Physical, chemical and operation parameters were measured; the activated sludge community (ciliates, flagellates, amoebae and small metazoa) was analysed for calculating SBI and SI. Floc and filamentous bacteria were examined and described accordingly with internationally adopted criteria. The results showed the full applicability of the studied techniques for optimizing the operation of a piggery slaughterhouse wastewater treatment plant.     

Dental wear estimation using a digital intra-oral optical scanner and an automated 3D computer vision method

The objective of this work was to propose an automated and direct process to grade tooth wear intra-orally. Eight extracted teeth were etched with acid for different times to produce wear and scanned with an intra-oral optical scanner. Computer vision algorithms were used for alignment and comparison among models. Wear volume was estimated and visual scoring was achieved to determine reliability. Results demonstrated that it is possible to directly detect submillimeter differences in teeth surfaces with an automated method with results similar to those obtained by direct visual inspection. The investigated method proved to be reliable for comparison of measurements over time.     

Trichinella spiralis: Growth of the intracellular (muscle) larva

Newborn larvae of Trichinella spiralis were infective when injected directly into the thigh muscle of mice and rats. Infections initiated in this manner resulted in synchronously growing populations of muscle larvae, thereby permitting a detailed study of larval growth to be carried out.In mice, the mean larval growth, as measured by increase in larval volume, occurred in three phases; an initial growth phase (Day 0–1), a lag phase (Days 1–3), and an exponential growth phase (Days 3–19). Larvae grew an average of 39% per day during the exponential phase.No further increase in larval volume was noted after Day 19. There was no statistically significant difference found in the rate of larval growth among individual mice for any given day. The larval growth rate was the same in rats as in mice.     

Characteristics of the interaction of the ferritin repressor protein with the iron-responsive element

Summary The iron-responsive regulation of ferritin mRNA translation is mediated by the specific interaction of the ferritin repressor protein (FRP) with the iron-responsive element (IRE), a highly conserved 28-nucleotide sequence located in the 5 untranslated region of ferritin mRNAs. The IRE alone is necessary and sufficient to confer repression of translation by FRP upon a heterologous message, chloramphenicol acetyltransferase, in an in vitro translation system. The activity of FRP is sensitive to iron in vivo. Cytoplasmic extracts of rabbit kidney cells show reduction of FRP activity when grown in the presence of iron, as detected by RNA band shift assay. Using a nitrocellulose filter binding assay to examine the interaction of FRP with the IRE in more detail, we find that purified FRP has a single high-affinity binding site for the IRE with aK _d of 20–50 pM. Hemin pretreatment decreases the total amount of FRP which can bind to the IRE. This effect is dependent on hemin concentration. Interestingly, the FRP which remains active at a given hemin concentration binds to the IRE with the same high affinity as untreated FRP. A variety of hemin concentrations were examined for their effect on preformed FRP/IRE complexes. All hemin concentrations tested resulted in rapid complex breakdown. The final amount of complex breakdown corresponds to the concentration of hemin present in the reaction. The effect of hemin on FRP activity suggests that a specific hemin binding site exists on FRP.Abbreviations IRE iron-responsive element - FRP ferritin repressor protein - CAT chloramphenicol acetyltransferase - ORF open reading frame     

Distribution and Abundance of the World's Smallest Primate,Microcebus berthae,in Central Western Madagascar

The distribution of most recently discovered or described lemur species remains poorly known, but many appear to have small geographical ranges, making them vulnerable to extinction. Research can contribute to future conservation actions on behalf of these species by providing accurate information on local distribution and abundance. The distribution of the world’s smallest primate, the endangered Madame Berthe’s mouse lemur (Microcebus berthae), is limited to the Menabe Central region of western Madagascar. This species was discovered in the 1990s, but many fundamental aspects of its ecology remain unknown. The aims of our study were therefore to determine the actual distribution of Microcebus berthae across the forests of this region, to estimate population density, and to examine the species’ response to anthropogenic activities. We established 35 1-km line transects across Menabe Central, on which we surveyed mouse lemurs by distance sampling and live trapping. Microcebus berthae does not occur in all remaining forests of this small region and its population density is highly heterogeneous, both across its geographic range and locally. Within its area of occupancy, the population of Microcebus berthae not only was distributed according to spatial heterogeneities of the habitat, but also responded to anthropogenic disturbances and varied seasonally. Our results indicate that Microcebus berthae is susceptible to habitat degradation and avoids human environments spatially. As none of the forest remnants in which the species still occurs were officially protected until recently, immediate conservation actions should focus on effectively protecting Kirindy and Ambadira forests.     

Involvement of IGF-2, IGF-1R,IGF-2R and PTEN in development of human tooth germ – an immunohistochemical study

Insulin-Like Growth Factor 2 (IGF-2) is a peptide hormone essential for prenatal growth and development. IGF-2 exerts its mitogenic effects via Insulin-Like Growth Factor 1 Receptor (IGF-1R), and is eliminated by binding to Insulin-Like Growth Receptor 2 (IGF-2R). IGF-2 is also negatively regulated by Phosphatase and Tensin Homolog (PTEN), a phosphatase mutated in various tumors. Not much is known about the interplay between these factors during human odontogenesis. In this study, expression patterns of IGF-2, IGF-1R, IGF-2R and PTEN were analyzed by double immunofluorescence in incisor human tooth germs during the foetal period of development between the 7^th and 20^th gestational week. Throughout the investigated period, IGF-2 was mostly expressed in enamel organ, whereas mild to moderate expression of PTEN could be seen in dental papilla and parts of enamel organ. Expression of IGF-1R was ubiquitous and displayed strong intensity throughout the entire enamel organ. In contrast, expression of IGF-2R had rather erratic pattern in enamel organ and dental papilla alike. Expression patterns of IGF-2, IGF-1R, IGF-2R and PTEN in highly proliferative cervical loops, as well as in differentiating pre-ameloblasts and pre-odontoblasts of cusp tip region during the early and late bell stages when enamel organ acquires definitive shape, indicate importance of these factors in crown morphogenesis of human incisor. Taken together, our data suggest the involvement of IGF-2, IGF-1R, IGF-2R and PTEN in temporo-spatial patterning of basic cellular processes (proliferation, differentiation) during normal tooth development. They are also relevant for improving knowledge of molecular basis of human odontogenesis.