Field but not lab paradigms support generalisation by predators of aposematic polymorphic prey: the Oophaga histrionica complex

The persistence of novel aposematic forms, and thereby the evolution of aposematic polymorphism, remain intriguing. Novel and rare forms could be disproportionally attacked by predators that already learned to avoid a pre-existing and more common aposematic form. Alternatively, novel forms could be less frequently attacked if predators are reluctant to attack unknown potential prey (neophobia) or if previous learning allows them to generalise and recognise the novel form as toxic. We used colour variation in polymorphic poison frogs (Oophaga histrionica complex) to test whether predators familiar with one aposematic form do generalise their avoidance behaviour to other aposematic forms. To strengthen our inference, we combined a field test of attack rates to local and non-local models with a lab experiment of generalisation capabilities by newly born chicks. Field predators attacked a significantly lower proportion of 529 aposematic compared to 150 cryptic models. Predators co-occurring with the local aposematic form of O. histrionica equally avoided non-local forms, especially in areas where the species was abundant. Forty-two lab chicks learned to discriminate between an aposematic and a cryptic image, but failed to generalise to other aposematic images, even though we tried with six combinations of aposematic forms. To better mimic the situation in the field, we further tested whether chicks trained with a set of four simultaneous aposematic images would generalise better. They failed to learn the discrimination task. Our data contrast with previous field studies on other poison frogs, and support a role for generalisation, and arguably not neophobia, in predator avoidance of novel aposematic forms.     

Foliar persistence and residual activity of methoxyfenozide against beet armyworm (Lepidoptera: Noctuidae)

A greenhouse study was conducted to investigate the persistence of methoxyfenozide in pepper (Capsicum annuum L.) foliage. An aqueous suspension of methoxyfenozide was sprayed on pepper plants at concentrations of 72 and 144 mg of active ingredient (a.i.)/L. Foliage was collected at different intervals of time (0, 3, 5, 10, 20, 30, 40, and 50 days) after the treatment, and the methoxyfenozide residue was measured by high‐performance liquid chromatography. The foliage was also used in bioassays to determine the residual toxicity on and the consumption rate of the third‐instar larvae of the beet armyworm, Spodoptera exigua (Hübner) (Lepidoptera: Noctuidae). The methoxyfenozide concentrations observed after 50 days had decreased to 19 and 69 μg/g per sample, corresponding to a loss of 61% and 28% from the application concentrations of 72 and 144 mg a.i./L, respectively. When fitting a first‐order kinetics degradation model, the half‐life (DT₅₀) of this compound was 76 days. Both application concentrations of methoxyfenozide caused a high mortality rate (≥97%) when the larvae were fed the pepper foliage collected at all of the time intervals. Lastly, at all of the time points, the consumption rate by the larvae was reduced to between 57% and 92% for both concentrations that were bioassayed. Our results indicate that, under the present greenhouse conditions, the degradation of methoxyfenozide was slower than that reported by other authors and that its residues were highly toxic to S. exigua larvae. The implications of these results for the management programs of this pest are discussed.     

Exploration of the ability of Coleus blumei to accumulate aluminum

In this study, the capacity of an ornamental species (Coleus blumei) to extract and accumulate aluminum was evaluated. The analyzed parameters were amount of soluble aluminum, radical growth, tolerance rate, bioaccumulation factor, and tissues aluminum concentration. The main limiting factor for aluminum accumulation is the availability of the metal. However, Coleus blumei can grow and accumulate up to 1445.7 mg kg(-1) of aluminum dry base. This plant can play an important role in the treatment of polluted water with metals, since it can grow in conditions with a pH of around 4.8. The aluminum tolerance rate showed for this plant ranged between 18.8% and 25%. Therefore, this species behaves as a non-accumulator, even though the bioaccumulation factor was 3098.5 L kg(-1).     

Situationally-sensitive knowledge translation and relational decision making in hyperacute stroke: a qualitative study

Stroke is a leading cause of disability. Early treatment of acute ischaemic stroke with rtPA reduces the risk of longer term dependency but carries an increased risk of causing immediate bleeding complications. To understand the challenges of knowledge translation and decision making about treatment with rtPA in hyperacute stroke and hence to inform development of appropriate decision support we interviewed patients, their family and health professionals. The emergency setting and the symptomatic effects of hyper-acute stroke shaped the form, content and manner of knowledge translation to support decision making. Decision making about rtPA in hyperacute stroke presented three conundrums for patients, family and clinicians. 1) How to allow time for reflection in a severely time-limited setting. 2) How to facilitate knowledge translation regarding important treatment risks and benefits when patient and family capacity is blunted by the effects and shock of stroke. 3) How to ensure patient and family views are taken into account when the situation produces reliance on the expertise of clinicians. Strategies adopted to meet these conundrums were fourfold: face to face communication; shaping decisions; incremental provision of information; and communication tailored to the individual patient. Relational forms of interaction were understood to engender trust and allay anxiety. Shaping decisions with patients was understood as an expression of confidence by clinicians that helped alleviate anxiety and offered hope and reassurance to patients and their family experiencing the shock of the stroke event. Neutral presentations of information and treatment options promoted uncertainty and contributed to anxiety. 'Drip feeding' information created moments for reflection: clinicians literally made time. Tailoring information to the particular patient and family situation allowed clinicians to account for social and emotional contexts. The principal responses to the challenges of decision making about rtPA in hyperacute stroke were relational decision support and situationally-sensitive knowledge translation.     

Laboratory-Based Surveillance of Neisseria meningitidis Isolates from Disease Cases in Latin American and Caribbean Countries, SIREVA II 2006-2010

Background

Published data on the epidemiology of meningococcal disease in Latin America and the Caribbean region is scarce and, when available, it is often published in Spanish and/or in non-peer-reviewed journals, making it difficult for the international scientific community to have access.

Methods

Laboratory data on 4,735 Neisseria meningitidis strains was collected and reported by the National Reference Laboratories in 19 Latin American countries and the Caribbean Epidemiology Centre (CAREC) between 2006 and 2010 as part of the work carried out by the SIREVA II network. Serogroup and MIC to penicillin, rifampin and chloramphenicol were determined.

Results

Isolates were mainly obtained from patients <5 years, but each year around 25% of isolates came from adult patients. Serogroup distribution was highly variable among countries. Serogroup C was the main cause of disease in Brazil; the majority of disease seen in the Southern cone was caused by serogroup B, but serogroup W135 strains have increased in recent years. In the Andean and Mexico, Central America and Caribbean regions, serogroups B and C were equally present, and serogroup Y was frequently isolated. Isolates were generally susceptible to chloramphenicol, penicillin and rifampin, but almost 60% of isolates characterized in Southern cone countries presented intermediate resistance to penicillin. Five rifampin-resistant isolates have been isolated in Uruguay and Brazil.

Conclusions

Serogroup distribution is highly variable among countries, but some geographic structuring can be inferred from these data. Epidemiological and laboratory data are scarce among Andean and Mexico, Central America and Caribbean countries. Evaluation and implementation of corrective measures on disease surveillance and reporting systems and the implementation of molecular diagnostic techniques and molecular characterization on meningococcal isolates are advised.     

Population dynamics of Caprella dilatata and Caprella equilibra (Peracarida: Amphipoda) in a Southwestern Atlantic harbour

We studied the population dynamics and reproductive biology of Caprella dilatata and Caprella equilibra in order to provide the basis for understanding the ecological role of both species in Mar del Plata Harbour. Caprellids and organisms from the fouling community were obtained by sampling in the harbour, monthly from April 2014 to March 2015. Mean density of C. dilatata was homogeneous during most of the study period (ca. 50–200 ind/100?g) and reached their maximum in May (ca. 650 ind/100?g), while C. equilibra did not show any differences during the sampling period (ca. 30 ind/100?g). Juveniles of C. dilatata reached their highest densities in May, while ovigerous females were at their maximum values in late spring, summer and early autumn, and no correlation was found between seawater temperature and monthly density. On the other hand, C. equilibra reached its maximum juvenile and ovigerous female densities in summer, and showed a positive correlation with seawater temperature. Sex-ratio was female biased in C. dilatata, but in C. equilibra it was equal between sexes. The number of eggs carried by females was positively correlated to the size in both species. The present study suggests that the population dynamics of C. equilibra are intimately related to seawater temperature, while for C. dilatata no relationship was found. Future studies of ecology and behaviour traits in caprellid species are needed in order to determine the ecological role and the environmental factors that could affect both species.     

Management of pain in sickle cell disease using biofeedback therapy: A preliminary study

Fifteen patients with a history of painful episodes of sickle cell disease were given training in progressive relaxation, thermal biofeedback, cognitive strategies, and self-hypnosis to help them develop self-management skills to relieve pain. Results show a 38.5% reduction in the number of emergency room visits, a 31% reduction in the number of hospitalizations, and a 50% reduction in the inpatient stay during the 6 months since the beginning of therapy compared to 6 months prior to therapy. Analgesic intake was reduced by 29% for those who were using it regularly. This is a preliminary study, and the results are considered only as suggestive of the potential use of biofeedback therapy and behavioral management in alleviating painful episodes in sickle cell disease.An earlier version of this paper was presented at the 6th Annual Convention of the American Association of Biofeedback Clinicians, Chicago, November 5, 1982.     

On the macromolecular composition of the jelly coat from Strongylocentrotus purpuratus eggs

The number of macromolecular components present in the egg jelly coat of Strongylocentrotus purpuratus was investigated. The material was prepared free from egg contaminants and examined for homogeneity by cellulose acetate electrophoresis, disc gel electrophoresis, ultracentrifugation and immunological studies. The electrophoretic and ultracentrifugal studies showed the presence of at least two components. The two-dimensional immunodiffusion tests using rabbit antiserum against whole jelly coat, exhibited four and immunoelectrophoresis five different antigens. In addition, it was possible to separate two components from gel filtration experiments with Sepharose 4B. It is concluded therefore that the S. purpuratus egg jelly coat contains minimally from two to five macromolecules.     

Lipidomic mass spectrometry and its application in neuroscience

Central and peripheral nervous systems are lipid rich tissues. Lipids, in the context of lipid-protein complexes, surround neurons and provide electrical insulation for transmission of signals allowing neurons to remain embedded within a conducting environment. Lipids play a key role in vesicle formation and fusion in synapses. They provide means of rapid signaling, cell motility and migration for astrocytes and other cell types that surround and play supporting roles neurons. Unlike many other signaling molecules, lipids are capable of multiple signaling events based on the different fragments generated from a single precursor during each event. Lipidomics, until recently suffered from two major disadvantages:(1) level of expertise required an overwhelming amount of chemical detail to correctly identify a vast number of different lipids which could be close in their chemical reactivity; and(2) high amount of purified compounds needed by analytical techniques to determine their structures. Advances in mass spectrometry have enabled overcoming these two limitations. Mass spectrometry offers a great degree of simplicity in identification and quantification of lipids directly extracted from complex biological mixtures. Mass spectrometers can be regarded to as mass analyzers. There are those that separate and analyze the product ion fragments in space(spatial) and those which separate product ions in time in the same space(temporal). Databases and standardized instrument parameters have further aided the capabilities of the spatial instruments while recent advances in bioinformatics have made the identification and quantification possible using temporal instruments.