Psychological consequences of prenatal diagnosis in a case of familial Angelman Syndrome

Angelman Syndrome (AS), characterized by mental retardation, absence of speech, seizures and motor dysfunction, is caused by genetic defects leading to loss of expression of the maternal copy of the chromosome 15q11–13 imprinted region. Most cases are sporadic, being caused by de novo deletion of maternal chromosome 15q11–13 (75%) or by paternal uniparental disomy (3–4%). Familial cases can occur, due to mutations in the UBE3A gene or in the imprinting center. We describe the case of a pregnant woman having two nephews with AS caused by a UBE3A mutation; lack of communication within the family led the woman to be completely unaware of the risk of disease recurrence until 15 weeks of gestation. UBE3A genetic testing revealed she carried the familial mutation 892–893delCT. Prenatal diagnosis was performed on amniotic fluid and demonstrated that the fetus had inherited the mutation. The unexpected diagnosis and the subsequent termination of the pregnancy caused the woman to undergo acute psychological distress showing relevant psychopathological symptoms. Nevertheless, at 2-year follow-up, adverse consequences were minimized, and the couple was planning a new pregnancy. Factors affecting the psychological outcome of abortion and the role of psychological support in reducing the risk of long-term unfavorable consequences are discussed. Copyright © 2006 John Wiley & Sons, Ltd.     

Quantitative determination of 1 -hydroxypyrene in bovine urine samples using high-performance liquid chromatography with fluorescence and mass spectrometric detection

An analytical method was developed to determine quantitatively 1-hydroxypyrene (OHP) in bovine urine samples. The procedure includes an enzymatic hydrolysis to cleave the conjugated metabolite, an enrichment step using solid phase extraction with a non-polar rinse step and elution with dichloromethane. A final clean-up on silicagel was performed before high-performance liquid chromatography (HPLC) analysis and fluorescence detection. Alternatively, HPLC and electrospray ionization in the negative ion mode applying selective ion monitoring acquisition revealed to be a highly sensitive detection method allowing the quantitation of low pg of OHP in the urine samples. The method was successfully applied to the determination of OHP in bovine urine samples from animals living in urban and rural areas. Urine concentrations of OHP were significantly higher (median 8.6 microg l(-1)) of bovines living close to a highway.     

Prediction of pesticide volatilization with PELMO 3.31

In the current EU risk assessment for pesticide registration, the European Community requires prediction of the concentration of each pesticide in air. A number of mathematical models are used to assess the fate of pesticides in groundwater, surface water and soil. PELMO 3.20 calculates the volatilization fluxes from bare soil and was improved in the new version PELMO 3.31 to include the effect of temperature and sorption in dry soil. The objective of this study was to evaluate the new version of PELMO 3.31 in predicting the pesticide volatilization under field conditions. Procymidone, malathion, and ethoprophos were the test compounds in two different seasons (autumn and winter). Comparing simulation results obtained with PELMO 3.31, after calibration, with the previous version PELMO 3.20 shows that the estimated volatilization results seems improved for malathion, similar or slightly overestimating in the warmer season for ethoprophos, and similar or slightly underestimating in the colder season for procymidone. The new release of PELMO allows a more accurate estimation of pesticides volatilization from soil as function of meteorological factors, especially for medium or low volatility pesticides. Some difficulties remain, such as the determination of the active air layer and the sorption increment with the soil drying.     

Sperm allocation in relation to male traits, female size, and copulation behaviour in freshwater crayfish species

Sperm competition is a well-recognised agent in the evolution of sperm and ejaculate structure, as well as variation in female quality. Models of the evolution of ejaculate expenditure predict that male body condition, female fecundity and the risk and intensity of sperm competition may be the ultimate factors shaping optimal ejaculate size. We investigated sperm allocation in Austropotamobius italicus, a freshwater crayfish exhibiting a coercive mating system and external fertilisation, in relation to male and female traits and copulation behaviour under laboratory conditions. We found that mating males were sensitive to female size and produced larger ejaculates when mating with larger females, which were more fecund in terms of number of eggs produced. We found no evidence for female egg production being sperm-limited, as the number of eggs was not dependent on male sperm expenditure. Copulation duration and number of ejaculations reliably predicted the amount of sperm transferred, and both these behavioural measures positively covaried with female body size. These results indicate that male freshwater crayfish can modulate their sperm expenditure in accordance with cues that indicate female fecundity. In addition, a novel finding that emerged from this study is the decrease in sperm expenditure with male body size, which may either suggest that large, old male crayfish are better able than small males to economise sperm at a given mating to perform multiple matings during a reproductive season, or that they experience senescence of their reproductive performance.     

The role of learning in the acquisition of threat-sensitive responses to predator odours

The supposition that prey animals respond to a predator with an intensity that matches the risk posed by the predator is known as the threat-sensitive predator avoidance hypothesis. Many studies have provided support for this hypothesis; yet, few studies have attempted to determine how such abilities are acquired by prey species. In this study, we investigated whether fathead minnows (Pimephales promelas) could learn to recognize an unknown predator (northern pike, Esox lucius) in such a way that they could match the intensity of their antipredator response with the threat posed by the predator. We exposed pike-naïve minnows to conspecific alarm cues paired with either a high or low concentration of pike odor. The following day, both groups were tested for a response to either high or low concentration of pike odor alone. We found that minnows conditioned with alarm cues paired with a given concentration of pike odor subsequently responded with a higher intensity to higher concentrations of pike odor, and with a lower intensity to lower concentrations of pike odor. These results demonstrate that during a single conditioning trial, minnows learn the identity of the predator in a threat-sensitive manner. Minnows use predator odor concentrations that they experience in subsequent interactions to adjust the intensity of their antipredator behavior.     

Threat-sensitive learning of predators by larval mosquitoes <Emphasis Type="Italic">Culex restuans</Emphasis>

A prerequisite for prey to show adaptive behavioural responses to predators is that the prey has the ability to recognise predators as threats. While predator recognition can be innate in many situations, learning is often essential. For many aquatic species, one common way to learn about predators is through the pairing of a novel predator odour with alarm cues released from injured conspecifics. One study with fish demonstrated that this mode of learning not only allows the prey to recognise the predatory cues as a threat, but also mediates the level of threat associated with the predator cues (i.e. threat-sensitive learning). When the prey is exposed to the novel predator with a high concentration of alarm cues, they subsequently show a high intensity of antipredator response to the predator cues alone. When exposed to the predator with a low concentration of alarm cues, they subsequently show a low-intensity response to the predator cues. Here, we investigated whether larval mosquitoes Culex restuans have the ability to learn to recognise salamanders as a threat through a single pairing of alarm cues and salamander odour and also whether they would learn to respond to salamander cues in a threat-sensitive manner. We conditioned individual mosquitoes with water or a low, medium or high concentration of crushed conspecific cues (alarm cues) paired with salamander odour. Mosquitoes exposed to salamander odour paired with alarm cues and subsequently exposed to salamander odour alone responded to the salamander as a threat. Moreover, the intensity of antipredator response displayed during the conditioning phase matched the response intensity during the testing phase. This is the first demonstration of threat-sensitive learning in an aquatic invertebrate.     

Copper (II) adsorption studies using models of synthetic humic acids

A polymer with characteristics similar to those of humic acids was obtained by synthesis reactions from oxidative polymerization in an alkaline medium using para-benzoquinone, hydroquinone and 4-aminobenzoic acid as precursors. Samples of natural and synthetic humic acid were used to examine the adsorption behavior of Cu²⁺ ions on these substrates. The mathematical models described by Langmuir and Freundlich equations were applied, yielding the maximum adsorption intensity values K′ (Langmuir), maximum adsorption capacity, b (Langmuir) and the adsorbent adsorption capacity, m (Freundlich). Based on solubility studies, pH 3 was selected for the development of the adsorption experiment. The Cu²⁺ ion presented a favorable adsorption, with RL (equilibrium parameter) responses in Langmuir isotherms falling within the desirable ranges.     

From repulsion to attraction: species- and spatial context-dependent threat sensitive response of the spider mite Tetranychus urticae to predatory mite cues

Prey perceiving predation risk commonly change their behavior to avoid predation. However, antipredator strategies are costly. Therefore, according to the threat-sensitive predator avoidance hypothesis, prey should match the intensity of their antipredator behaviors to the degree of threat, which may depend on the predator species and the spatial context. We assessed threat sensitivity of the two-spotted spider mite, Tetranychus urticae, to the cues of three predatory mites, Phytoseiulus persimilis, Neoseiulus californicus, and Amblyseius andersoni, posing different degrees of risk in two spatial contexts. We first conducted a no-choice test measuring oviposition and activity of T. urticae exposed to chemical traces of predators or traces plus predator eggs. Then, we tested the site preference of T. urticae in choice tests, using artificial cages and leaves. In the no-choice test, T. urticae deposited their first egg later in the presence of cues of P. persimilis than of the other two predators and cue absence, indicating interspecific threat-sensitivity. T. urticae laid also fewer eggs in the presence of cues of P. persimilis and A. andersoni than of N. californicus and cue absence. In the artificial cage test, the spider mites preferred the site with predator traces, whereas in the leaf test, they preferentially resided on leaves without traces. We argue that in a nonplant environment, chemical predator traces do not indicate a risk for T. urticae, and instead, these traces function as indirect habitat cues. The spider mites were attracted to these cues because they associated them with the existence of a nearby host plant.     

Waste foundry sand used to cover organic waste in landfills

Journal of Material Cycles and Waste Management - Waste foundry sand (WFS) is a waste generated during the molding of metal parts and primarily discarded in landfills, which generates environmental...