A Parasitoid Wasp Induces Overwintering Behaviour in Its Spider Host

Parasites and parasitoids control behaviors of their hosts. However, the origin of the behavior evoked by the parasitic organism has been rarely identified. It is also not known whether the manipulation is universal or host-specific. Polysphinctine wasps, koinobiont ectoparasitoids of several spider species that manipulate host web-spinning activity for their own protection during pupation, provide an ideal system to reveal the origin of the evoked behavior. Larva of Zatypota percontatoria performed species-specific manipulation of theridiid spiders, Neottiura bimaculata and Theridion varians, shortly before pupation. Parasitized N. bimaculata produced a dense web, whereas parasitized T. varians built a cupola-like structure. The larva pupated inside of either the dense web or the cupola-like structure. We discovered that unparasitized N. bimaculata produce an analogous dense web around their eggsacs and for themselves during winter, while T. varians construct an analogous ‘cupola’ only for overwintering. We induced analogous manipulation in unparasitized hosts by altering ambient conditions. We discovered that the behavior evoked by larvae in two hosts was functionally similar. The larva evoked protective behaviors that occur in unparasitized hosts only during specific life-history periods

PolyQ Repeat Expansions in ATXN2 Associated with ALS Are CAA Interrupted Repeats

Amyotrophic lateral sclerosis (ALS) is a devastating, rapidly progressive disease leading to paralysis and death. Recently, intermediate length polyglutamine (polyQ) repeats of 27–33 in ATAXIN-2 (ATXN2), encoding the ATXN2 protein, were found to increase risk for ALS. In ATXN2, polyQ expansions of ≥34, which are pure CAG repeat expansions, cause spinocerebellar ataxia type 2. However, similar length expansions that are interrupted with other codons, can present atypically with parkinsonism, suggesting that configuration of the repeat sequence plays an important role in disease manifestation in ATXN2 polyQ expansion diseases. Here we determined whether the expansions in ATXN2 associated with ALS were pure or interrupted CAG repeats, and defined single nucleotide polymorphisms (SNPs) rs695871 and rs695872 in exon 1 of the gene, to assess haplotype association. We found that the expanded repeat alleles of 40 ALS patients and 9 long-repeat length controls were all interrupted, bearing 1–3 CAA codons within the CAG repeat. 21/21 expanded ALS chromosomes with 3CAA interruptions arose from one haplotype (GT), while 18/19 expanded ALS chromosomes with <3CAA interruptions arose from a different haplotype (CC). Moreover, age of disease onset was significantly earlier in patients bearing 3 interruptions vs fewer, and was distinct between haplotypes. These results indicate that CAG repeat expansions in ATXN2 associated with ALS are uniformly interrupted repeats and that the nature of the repeat sequence and haplotype, as well as length of polyQ repeat, may play a role in the neurological effect conferred by expansions in ATXN2

The 'antisocial' person: an insight in to biology, classification and current evidence on treatment

<p>Abstract</p> <p>Background</p> <p>This review analyses and summarises the recent advances in understanding the neurobiology of violence and empathy, taxonomical issues on defining personality disorders characterised by disregard for social norms, evidence for efficacy of different treatment modalities and ethical implications in defining 'at-risk' individuals for preventive interventions.</p> <p>Methods</p> <p>PubMed was searched with the keywords 'antisocial personality disorder', 'dissocial personality disorder' and 'psychopathy'. The search was limited to articles published in English over the last 10 years (1999 to 2009)</p> <p>Results</p> <p>Both diagnostic manuals used in modern psychiatry, the <it>Diagnostic and Statistical Manual </it>published by the American Psychiatric Association and the <it>International Classification of Diseases </it>published by the World Health Organization, identify a personality disorder sharing similar traits. It is termed antisocial personality disorder in the diagnostic and statistical manual and dissocial personality disorder in the <it>International Classification of Diseases</it>. However, some authors query the ability of the existing manuals to identify a special category termed 'psychopathy', which in their opinion deserves special attention. On treatment-related issues, many psychological and behavioural therapies have shown success rates ranging from 25% to 62% in different cohorts. Multisystemic therapy and cognitive behaviour therapy have been proven efficacious in many trials. There is no substantial evidence for the efficacy of pharmacological therapy. Currently, the emphasis is on early identification and prevention of antisocial behaviour despite the ethical implications of defining at-risk children.</p> <p>Conclusions</p> <p>Further research is needed in the areas of neuroendocrinological associations of violent behaviour, taxonomic existence of psychopathy and efficacy of treatment modalities.</p

Sediment source fingerprinting: benchmarking recent outputs, remaining challenges and emerging themes

Abstract: Purpose: This review of sediment source fingerprinting assesses the current state-of-the-art, remaining challenges and emerging themes. It combines inputs from international scientists either with track records in the approach or with expertise relevant to progressing the science. Methods: Web of Science and Google Scholar were used to review published papers spanning the period 2013–2019, inclusive, to confirm publication trends in quantities of papers by study area country and the types of tracers used. The most recent (2018–2019, inclusive) papers were also benchmarked using a methodological decision-tree published in 2017. Scope: Areas requiring further research and international consensus on methodological detail are reviewed, and these comprise spatial variability in tracers and corresponding sampling implications for end-members, temporal variability in tracers and sampling implications for end-members and target sediment, tracer conservation and knowledge-based pre-selection, the physico-chemical basis for source discrimination and dissemination of fingerprinting results to stakeholders. Emerging themes are also discussed: novel tracers, concentration-dependence for biomarkers, combining sediment fingerprinting and age-dating, applications to sediment-bound pollutants, incorporation of supportive spatial information to augment discrimination and modelling, aeolian sediment source fingerprinting, integration with process-based models and development of open-access software tools for data processing. Conclusions: The popularity of sediment source fingerprinting continues on an upward trend globally, but with this growth comes issues surrounding lack of standardisation and procedural diversity. Nonetheless, the last 2 years have also evidenced growing uptake of critical requirements for robust applications and this review is intended to signpost investigators, both old and new, towards these benchmarks and remaining research challenges for, and emerging options for different applications of, the fingerprinting approach

The feeding tube of cyst nematodes: characterisation of protein exclusion

Plant parasitic nematodes comprise several groups; the most economically damaging of these are the sedentary endoparasites. Sedentary endoparasitic nematodes are obligate biotrophs and modify host root tissue, using a suite of effector proteins, to create a feeding site that is their sole source of nutrition. They feed by withdrawing host cell assimilate from the feeding site though a structure known as the feeding tube. The function, composition and molecular characteristics of feeding tubes are poorly characterised. It is hypothesised that the feeding tube facilitates uptake of host cell assimilate by acting as a molecular sieve. Several studies, using molecular mass as the sole indicator of protein size, have given contradictory results about the exclusion limits of the cyst nematode feeding tube. In this study we propose a method to predict protein size, based on protein database coordinates in silico. We tested the validity of these predictions using travelling wave ion mobility spectrometry--mass spectrometry, where predictions and measured values were within approximately 6%. We used the predictions, coupled with mass spectrometry, analytical ultracentrifugation and protein electrophoresis, to resolve previous conflicts and define the exclusion characteristics of the cyst nematode feeding tube. Heterogeneity was tested in the liquid, solid and gas phase to provide a comprehensive evaluation of three proteins of particular interest to feeding tube size exclusion, GFP, mRFP and Dual PI. The data and procedures described here could be applied to the design of plant expressed defence compounds intended for uptake into cyst nematodes. We also highlight the need to assess protein heterogeneity when creating novel fusion proteins

Description of the male Hymenoepimecis japi Sobczak et al. 2009 (Hymenoptera, Ichneumonidae) parasitoid of Leucauge roseosignata Mello-Leit\ue3o 1943 (Araneae: Tetragnathidae)

The male of Hymenoepimecis japi (Hymenoptera, Ichneumonidae, Pimplinae) is described and illustrated. The specimen was collected in a modified web (cocoon web) of Leucauge roseosignata (Araneae, Tetragnathidae) made in a laboratory. Both, host and parasitoid were collected in Reserva Biológica Serra do Japi, located in Jundiaí, São Paulo, Brazil

Description of the male Hymenoepimecis japi Sobczak et al. 2009 (Hymenoptera, Ichneumonidae) parasitoid of Leucauge roseosignata Mello-Leitão 1943 (Araneae: Tetragnathidae)

The male of Hymenoepimecis japi (Hymenoptera, Ichneumonidae, Pimplinae) is described and illustrated. The specimen was collected in a modified web (cocoon web) of Leucauge roseosignata (Araneae, Tetragnathidae) made in a laboratory. Both, host and parasitoid were collected in Reserva Biológica Serra do Japi, located in Jundiaí, São Paulo, Brazil

Parasitoid-induced mortality of Araneus omnicolor (Araneae, Araneidae) by Hymenoepimecis sp (Hymenoptera, Ichneumonidae) in southeastern Brazil

All species included in the Polysphincta genus-group develop as ectophagous parasitoids of active spiders, killing their hosts prior to pupation. However, little information regarding natural history and ovipositing behavior of most species are available. In this study we inspected 85 webs of Araneus omnicolor to evaluate the frequency of parasitism and host size preferences of the wasp Hymenoepimecis sp. We also described the web characteristics of normal and parasitized spiders and the wasp ovipositing behavior. About 41% of the adult females of A. omnicolor inspected were parasitized. The highest incidence of parasitism was observed among relatively small females while no egg or larva was found in large individuals. Araneus omnicolor builds a strong web composed of an orb and barrier threads, where the spider rests within a curled leaf. The parasitoid larva builds its cocoon within this refuge, and modified cocoon webs were not observed. The ovipositing behavior of Hymenoepimecis sp. was very similar to that of Hymenoepimecis argyraphaga parasitizing Leucauge argyra, including the position of the sting, the killing of a previously attached larva, and the expelling of the egg from the base of the ovipositor.94322322