effect of the extracellular environment on the composition and function of synapses

Otto-von-Guericke-Universität magdeburg, Fakultät für Naturwissenschaften, Dissertation, 2015

Two decades of colonization of the urban environment of Porto Alegre, southern Brazil, by Drosophila paulistorum (Diptera, Drosophilidae)

Drosophila paulistorum Dobzhansky & Pavan, 1949 had initially been considered absent in anthropogenically disturbed environments, but in 1985 the detection of the species in Porto Alegre city, southern Brazil, suggested its potential to colonize new habitats and laid the foundations for ecologic studies on this species' populations. This study followed the variations in D. paulistorum populations in this town almost 20 years after its first local record. Drosophilid specimens were collected in sites with different urbanization grades and the results point to the expressive decline in D. paulistorum populations in Porto Alegre. This decline may be linked to urban growth and to naturally driven population decline, as imputed to climatic changes like variations in maximum and minimum temperatures as a consequence of a global climate warming. Also, the recent introduction of exotic species Zaprionus indianus Gupta, 1970 seems to play a role in this scenario, changing the interactions between native species.

Seasonal variations in the intermediate metabolism of the crayfish Parastacus brasiliensis (Crustacea, Decapoda, Parastacidae) in the natural environment and experimental culture

The goal of this study was to evaluate the effects of seasonal variations on energy metabolism in different tissues of the freshwater crayfish Parastacus brasiliensis (von Martens, 1869). Crayfish were collected monthly from January 2001 to January 2003 in São Francisco de Paula, Rio Grande do Sul, Brazil, in a stream and in a culture tank. Haemolymph samples were collected from each crayfish in the field with a syringe, by puncturing the membrane at the base of the chelipeds. Hepatopancreas, gills, and abdominal muscle were removed for determination of free glucose, glycogen, total lipids, and triglycerides. The haemolymph samples were used for determination of glucose, total proteins, total lipids, and triglycerides. Statistical analysis revealed significant differences in biochemical composition in crayfish collected in the stream compared to the experimental tank during the year, principally in glucose and triglycerides in haemolymph, glycogen and total lipids in all tissues study, and triglycerides only in abdominal muscle. The regular food intake partially modified these seasonal variations of the metabolic pattern. Environmental conditions (e.g., food availability and water temperature) and reproductive period appeared to be the main factors influencing the seasonal patterns of variation in energy metabolism.

Phosphodiesterase-5 inhibition mimics intermittent reoxygenation and improves cardioprotection in the hypoxic myocardium.

Although chronic hypoxia is a claimed myocardial risk factor reducing tolerance to ischemia/reperfusion (I/R), intermittent reoxygenation has beneficial effects and enhances heart tolerance to I/R. AIM OF THE STUDY: To test the hypothesis that, by mimicking intermittent reoxygenation, selective inhibition of phosphodiesterase-5 activity improves ischemia tolerance during hypoxia. Adult male Sprague-Dawley rats were exposed to hypoxia for 15 days (10% O₂) and treated with placebo, sildenafil (1.4 mg/kg/day, i. p.), intermittent reoxygenation (1 h/day exposure to room air) or both. Controls were normoxic hearts. To assess tolerance to I/R all hearts were subjected to 30-min regional ischemia by left anterior descending coronary artery ligation followed by 3 h-reperfusion. Whereas hypoxia depressed tolerance to I/R, both sildenafil and intermittent reoxygenation reduced the infarct size without exhibiting cumulative effects. The changes in myocardial cGMP, apoptosis (DNA fragmentation), caspase-3 activity (alternative marker for cardiomyocyte apoptosis), eNOS phosphorylation and Akt activity paralleled the changes in cardioprotection. However, the level of plasma nitrates and nitrites was higher in the sildenafil+intermittent reoxygenation than sildenafil and intermittent reoxygenation groups, whereas total eNOS and Akt proteins were unchanged throughout. CONCLUSIONS: Sildenafil administration has the potential to mimic the cardioprotective effects led by intermittent reoxygenation, thereby opening the possibility to treat patients unable to be reoxygenated through a pharmacological modulation of NO-dependent mechanisms.

Bacillus sphaericus mosquito pathogens in the aquatic environment

The fate of Bacillus sphaericus spores in the aquatic environment was investigated by suspending spores in dialysis bags in fresh and seawater. Spore viability was lost more rapidly in seawater. Neither B. sphaericus nor B. thuringiensis israelensis (B.t.i.) spores mixed with pond sediment appeared to attach to the sediment. However, rapid decrease in B.t.i. toxicity suggested attachment of parasporal bodies to sediment. B. sphaericus toxin settled more slowly and less completely. B. sphaericus spores fed to larvae of four aquatic invertebrates were mostly eliminated from the animal gut in less than one week. An exception was the cranefly (Tipula abdominalis) where spores persisted in the posterior gut for up to five weeks.

Health and the Built Environment, Sources of Information

The Institute of Public Health in Ireland (IPH) has produced a series of reviews which look at the health impacts of identified subject areas. Four reviews have been produced in the areas of employment, transport, the built environment and education. All reviews may be found at http://www.publichealth.ie/ireland/hiaresources. This resource supplements the ‘Health Impacts of Built Environment’ report. It highlights a number of organisations whose work considers issues relevant to the relationship between health and built environment.

Health Impacts of the Built Environment: A review

This review is the third in the series and illustrates how the built environment impacts on health. It also highlights the unequal distribution of these impacts on different sections of the population. We hope it will help inform debate about the links between the built environment and health and be a useful resource for those working to influence public policy for health at local and national level across the island. The review has an extensive reference list. To supplement the health impacts of the built environment review a 'sources of information' list has been developed which highlights a number of organisations whose work considers issues relevant to the relationship between health and the built environment.

Ireland on the move: Enhancing opportunities for physical activity in the built environment

The Institute of Public Health in Ireland recently hosted a seminar on physical activity. The seminar presentations were: Ms Teresa Lavin, IPH - Physical activity and the built environment in Ireland Prof James Sallis, Professor of Psychology at San Diego State University and Director of Active Living Research - Translating evidence from physical activity research into practice.

An Assessment of the Microbiology of Hand Contact Surfaces in the Retail Environment

This study aimed to assess the microbiology of food and hand contact surfaces in the retail environment and the potential for these surfaces to act as vehicles for the spread of foodborne pathogens. During the survey, 10 stores in the Republic of Ireland (ROI) were visited by student Environmental Health Officers (EHOs) who took swab samples from four surfaces: conveyor belts, long-life shopping bags, shopping trolley handles and keypads on card payment units. The swab samples were examined for the presence of the pathogens Salmonella, Campylobacter and Listeria. The Aerobic Colony Counts, as well as the levels of E. coli and Enterobacteriaceae, were also determined. In addition, structured questionnaires were used with retailers to establish the stores’ regimes for the cleaning of conveyor belts. Similarly, shoppers donating their long-life shopping bags for sampling were questioned about how they normally use these bags, and the results were compared with those from the microbiological survey. The results indicated that the hygiene of the surfaces sampled was good, with Salmonella, Campylobacter and Listeria not detected in any of the samples, and levels of both Enterobacteriaceae and E. coli were below the limits of detection in all but one sample. Aerobic Colony Counts varied but none of the results obtained would be deemed ‘unacceptable’ or ‘unsatisfactory’ under guidelines for ready-to-eat foods

Effects of the social environment on the survival and fungal resistance of ant brood

The phenotype of social animals can be influenced by genetic, maternal and environmental effects, which include social interactions during development. In social insects, the social environment and genetic origin of brood can each influence a whole suite of traits, from individual size to caste differentiation. Here, we investigate to which degree the social environment during development affects the survival and fungal resistance of ant brood of known maternal origin. We manipulated one component of the social environment, the worker/brood ratio, of brood originating from single queens of Formica selysi. We monitored the survival of brood and measured the head size and ability to resist the entomopathogenic fungus Beauveria bassiana of the resulting callow workers. The worker/brood ratio and origin of eggs affected the survival and maturation time of the brood and the size of the resulting callow workers. The survival of the callow workers varied greatly according to their origin, both in controls and when challenged with B. bassiana. However, there was no interaction between the fungal challenge and either the worker/brood ratio or origin of eggs, suggesting that these factors did not affect parasite resistance in the conditions tested. Overall, the social conditions during brood rearing and the origin of eggs had a strong impact on brood traits that are important for fitness. We detected a surprisingly large amount of variation among queens in the survival of their brood reared in standard queenless conditions, which calls for further studies on genetic, maternal and social effects influencing brood development in the social insects.

Study of adaptation and validation of the Practice environment scale of the nursing work index for the portuguese reality

Objective: Testing the psychometric properties of the Portuguese version of the Practice Environment Scale of the Nursing Work Index. Method: A descriptive, analytical and cross-sectional study, for the cross-cultural adaptation and validation of the psychometric properties of the scale. The study participants were 236 nurses from two hospitals in the regions of Lisbon and Vale do Tejo. Results: The 0.92 Cronbach’s alpha was obtained for overall reliability and support of a five-dimension structure. Conclusion: The excellent quality of adjustment of analysis confirms the validity of the adapted version to hospital care settings, although there was no total coincidence of items in the five dimensions


Dimensions of national culture and the accounting environment -The Spanish case-

Gray (1988) has put forward a hypothesis on how a national accountingenvironment might reflect the cultural dimensions identified by Hofstede (1980, 1983). A number of studies have tested Gray's hypothesis, including one by Pourjalali and Meek (1995) which identified a match between changes in cultural dimensions and the accounting environment in Iran following the revolution. In this paper we replicate this work in the context of Spain following the death of Franco in 1975 and the emergence of a democratic constitution in 1978. Specifically, we: 1) Consider Gray's hypothesis built on Hofstede's cultural dimensions and review some empirical tests of the hypotheses.2) Building on the work of Hofstede and Gray, we: put forward some hypotheses on how we would expect cultural dimensions to change in Spain with the transition to democracy.3) Review developments in accounting in Spain following the transition to democracy, in order to identify how well these fit with our hypotheses.