Ontogenetic diet shifts: an additional mechanism for successful invasion of a piranha species in a Neotropical floodplain.

Ontogenetic shifts in food preference reduces intraspecific competition as immature individuals eat different food types than adults. This diet plasticity could facilitate species' ability to successfully invade and establish itself in a new environment, even when co-occurring with phylogenetically close species. Here, ontogenetic diet shifts of a non-native piranha species (Serrasalmus marginatus) was tested by analyzing the relationship between its body length and the carbon and nitrogen stable isotope signatures.

Invasion and Spreading of Drosophila nasuta (Diptera, Drosophilidae) in the Caatinga Biome, Brazil.

Biological invasions are one of the main causes of biodiversity loss, and it is essential to understand the pattern and rate of expansion of invasive species outside their native distribution. In this study, we documented the invasion of the Asian fruit fly, Drosophila nasuta Lamb, in the Caatinga, and measured its geographical distribution in this environment, which covers 11% of the Brazilian territory. We collected drosophilids in eight sites distributed in the north of the Caatinga (in the state of Ceará), in the south (in Bahia), in the east (in Pernambuco), and in the west (in Piauí), as well as in sites in the central area of the biome.

Fire increases the productivity of sugarcane, but it also generates ashes that negatively affect native fish species in aquatic systems.

Sugarcane is one of the main crops used around the world as a feedstock for the production of sucrose and biofuel. Prior to harvesting, sugarcane dry leaves are burned to facilitate manual cutting and enhance productivity. This practice generates ashes from sugarcane straw (hereafter referred as SCA), which may be carried to aquatic ecosystems, where its impacts on organisms and ecosystem integrity remain unknown.

Dry season limnological conditions and basin geology exhibit complex relationships with δ13C and δ15N of carbon sources in four Neotropical floodplains.

Studies in freshwater ecosystems are seeking to improve understanding of carbon flow in food webs and stable isotopes have been influential in this work. However, variation in isotopic values of basal production sources could either be an asset or a hindrance depending on study objectives. We assessed the potential for basin geology and local limnological conditions to predict stable carbon and nitrogen isotope values of six carbon sources at multiple locations in four Neotropical floodplain ecosystems (Paraná, Pantanal, Araguaia, and Amazon).

Diet-tissue discrimination factors (Δ(13) C and Δ(15) N) and turnover rate in somatic tissues of a neotropical detritivorous fish on C3 and C4 diets.

In this study, diet-tissue discrimination factors and turnover rates were determined from the somatic tissues of a detritivorous fish Prochilodus lineatus. The carbon (Δ(13) C) and nitrogen (Δ(15) N) diet-tissue discrimination factors varied for all feed rations with a range of Δ(13) C values between -1·9 and 3·6‰ and Δ(15) N between 3·3 and 5·7‰. Carbon turnover rate in the blood was 23·1 days for the C3 ration and 34·7 days for the C4 ration, in the liver was 9·9 days under the C3 ration and nitrogen turnover rate was the same (23·1 days) in the liver for both C4 and C3 -C4 rations, and 13·9 days in the muscle for C3 -C4 ration.

The influence of fish cage culture on δ13C and δ15N of filter-feeding Bivalvia (Mollusca).

The objective of this study was to evaluate the effect of Oreochromis niloticus cage culture promoted variations in the δ13C and δ15N in Corbicula fluminea (Mollusca; Bivalvia) and in the sediment of an aquatic food web. Samples were taken before and after net cage installation in the Rosana Reservoir (Paranapanema River, PR-SP). Samples of specimens of the bivalve filterer C.

Variability in the trophic position of larval fishes in the upper Paraná floodplain based on δ15N.

The upper Paraná River floodplain is composed of several marginal lagoons, making it a natural breeding ground for many fish species at developmental stages. The aim of this study is to estimate the trophic positions of these fishes based on feed intake (measured via diet) and nitrogen assimilation (measured via δ(15)N). The monthly samplings were concentrated during the spawning season in the Ivinheima River, which is located in the upper Paraná River floodplain.

[Measles in the Local Health Unit Naples 4: vaccination coverage, epidemic 2001-2002 and prevention strategies].

The authors have analysed vaccination coverage for measles. The active offer of the vaccine brought about an increase of the vaccination coverage but participation to vaccination proved unsatisfactory between 1995 and 2000. The measles epidemic reported 1367 cases, of which 125 were hospitalised (3 cases presented complications).

Carbon sources and trophic position of the main species of fishes of Baía River, Paraná River floodplain, Brazil.

In order to verify the carbon source and trophic position of the main species of fishes, of the Paraná River floodplain, we analysed the proportion of stable carbon (delta 13C) and nitrogen (delta 15N) isotopes in muscle of fishes sampled in the rainy season. We analyzed adult individuals of Loricariichthys platymetopon, Schizodon borellii, Leporinus lacustris, Auchenipterus osteomystax, Iheringichthys labrosus, Leporinus friderici, and Serrasalmus marginatus. These data were compared with the results obtained by the analyzing stomach contents.

[Anaphylactic reaction to thiopental. A case documented by tryptase values and RAST].

During general anesthesia adverse reactions are not uncommon, and the hypothesis of an anaphylactic response cannot be excluded. In these situations, a differential diagnosis from other events which often present identical clinical manifestations is necessary. For this purpose measurement of serum tryptase, as a biochemical marker of the release of mast-cell granules, is considered a valuable and specific method, especially if it is carried out on several hematic samples, obtained in successive times, for pointing out the progressive reduction of the values.

Haemodynamic and haemoximetric aspects of experimental orthotopic liver transplantation: comparison between two different doses of propofol.

Objective: Evaluation of haemodynamic and gas exchange modifications using propofolnitrous oxide anaesthesia after ketamine induction during experimental orthotopic liver transplantation (OLT).

Design: Measurements of haemodynamic and haemoximetric effects of two anaesthesiological conditions, differing each other for the different dose of propofol, performed in an experimental model characterized by temporary anhepatism followed by revascularization.

Setting: Surgical experimental laboratory of the University Hospital of Florence.

Prevention of anaphylactic-anaphylactoid reactions to anesthetics in high-risk allergic patients.

To confirm the role of preventive procedures in high-risk allergic patients, immunological tests in vivo for anesthetics were carried out in 251 atopic patients. The 6-month follow-up showed a complete absence of adverse reactions during the clinical use of hypnotic and muscle relaxant drugs. In the case of local anesthetics, five adverse reactions were observed after dental treatment--four were related to a psychogenic mechanism, and one could not be clearly linked to the local anesthetic.