Search

Biological divergence results from several mechanisms. Defensive mechanisms, such as Batesian mimicry, can cause reproductive isolation via temporal segregation in foraging activity, particularly, in species that closely associate with their model. This seems to be the case of ant-eating spiders, which can be inaccurate Batesian mimics of their prey. Here, we focused on Zodarion nitidum, which has two forms occurring in sympatry, black and yellow. Given the expected noticeable impact of their colour differences on the spiders' interactions with their potential predators and prey, we investigated whether these morphotypes have diverged in other aspects of their biology. We measured the two morphotypes' phenotypic resemblance to a mimetic model, tested whether they were protected from predators, investigated their circadian activity, surveyed the prey they hunted, modelled their distributions, performed crossing experiments and estimated their degree of genetic differentiation. We found that the black morphotype is ant-like, resembling Messor ants, and it was not distinguishable from their ant models by four potential predators. In contrast, the yellow morphotype seems to use predator avoidance as a defensive strategy. Additionally, the two morphotypes differ in their circadian activity, the yellow morphotype being nocturnal and the black one being diurnal. The two morphotypes hunt and associate with different ant prey and possess marked differences in venom composition. Finally, crossing trials showed complete pre-mating isolation between the two morphotypes, but there was no evidence of genetic (mitochondrial data) or environmental niche differentiation. We conclude that the two morphotypes show evidence of a deep differentiation in morphological, behavioural, physiological and ecological traits that evolved together as part of the spider's diverging lifestyles.

The objective of this study was to assess the 10-year prevalence of latent tuberculosis infection (LTBI) among Apulian patients with rheumatic diseases (RDs). Secondary endpoint was to record new cases of active TB disease and LTBI among patients treated with biologic disease-modifying antirheumatic drugs (bDMARDs).We analysed the results from the patients included in the BIOPURE registry from 2009 to 2018, who underwent QuantiFERON-TB Gold In-tube (QFT-GIT) test as screening before biologic treatment. Demographic and clinical data were recorded at the time of the first QFT-GIT test. Administration of preventive therapy and bDMARD treatments were recorded for patients with positive QFT-GIT test. All new tuberculosis infections were recorded during the follow-up.The final study population included 3028 patients (855 Rheumatoid Arthritis, 1001 Psoriatic Arthritis, 833 spondyloarthritis, 130 connective tissue diseases, 33 systemic vasculitis, and 176 other inflammatory rheumatic conditions), more frequently female (67.2%), with a mean age of 52 ± 18 years. Patients with QFT-GIT positive test were elderly, predominantly male with higher prevalence of diabetes as comorbidity. The 10-year prevalence of LTBI was 10.8%. Of note, no cases of TB reactivation were recorded in patients who completed preventive therapy treatment. Three-thousand sixteen patients were followed overtime (42.6±30 months), and 5 (0.2%) developed active TB which corresponds to 0.47 cases per 1000 person-years.In the 10-year observation, the use of biologic therapy seems to be safe in rheumatologic patients with positive QFT-GIT test treated according to current recommendations. Nevertheless, cases of primary TB disease did occur during treatment with biologics.

Generalist predators have evolved a variety of behavioural adaptations in prey capture to effectively subdue different prey types. Such predators use a conditional hunting strategy. Among spiders, representatives of Gnaphosidae are known to use either venom attack (subduing prey with venom) or silk attack (subduing prey with silk). In this study, we aimed to test the hypothesis of the conditional use of prey capture strategy (venom versus silk attack) in two species, Drassodes sp. and Zelotes sp. We also measured the size of their venom glands and the number of their piriform glands in order to reveal whether behavioural adaptations are paralleled with morphological ones. As prey, we used other spiders of variable sizes as these are considered dangerous prey. We found that Drassodes used mainly silk attack, while the majority of Zelotes used venom attack. The probability of using silk attack increased with predator/prey body length ratio in Drassodes, but not in Zelotes. Then, we disabled silk use in individuals of both species. All disabled Drassodes used venom attack, but about half of individuals attempted to use silk attack first. All Zelotes used venom attack, and none attempted to use silk attack first. We found significantly larger venom glands in Drassodes than in Zelotes, while the number of piriform silk glands was similar. The behavioural adaptations are, thus, not paralleled with morphological (i.e., venom and silk gland size) ones. Our results suggest that both Drassodes and Zelotes can use both attack strategies with similar efficacy.

Female mating history can have a strong effect on male fertilization success. Although males often prefer to mate with virgin females, they often also engage with mated females. As the intensity of sperm competition can differ among mated females, males are expected to evolve means to identify their status. In spiders, males often use female silk to gather information about female quality. Males of many spider species deposit mating plugs into female genitalia to hinder further copulations. We tested whether males of the foliage‐dwelling, plug‐producing spider Philodromus cespitum, which is an important natural enemy of pests, discriminate between females of different mating status and whether they can determine the extent of genital plugging in mated females solely on the basis of cues gained from deposited female silk. We presented males with draglines of females that varied in either mating status (virgin vs. mated), the extent of plugging (small vs. big plug), or the age of the plug (fresh vs. old plug) and examined their mate preferences. Additionally, we tested whether males were attracted to volatile cues produced by female bodies. Our experiments revealed that males preferred draglines of virgin females to those of mated females, and mated females with small plugs to those with large plugs. They were also attracted to female volatile cues. This study suggests that males are able to extract fine‐scale information on mating status from female draglines.

We performed a meta-analysis of 58 published studies where we investigated (a) the overall effect of spiders on pest density and crop performance; (b) the extent to which the biocontrol efficacy of spiders depends on the taxonomy of pests (aphids, leafhoppers, beetles, and lepidopteran larvae), the hunting strategy of spiders (hunters, web-weavers), crop type (vine, cabbage, wheat, rice), climate, and geography.

1. Feeding behaviour of generalist and specialist predators is determined by a variety of trophic adaptations. Specialised prey‐capture adaptations allow specialists to catch relatively large prey on a regular basis. As a result, specialists might be adapted to exploit each item of prey more thoroughly than do generalists. 2. It was expected that obligatory specialist cursorial spiders would feed less frequently than generalists but for a longer time and, thus, that their foraging pause would be longer. First, the feeding frequencies of three generalist spider species (Cybaeodamus taim, Harpactea hombergi, Hersiliola sternbergsi) were compared with those three phylogenetically related specialist species: myrmecophagous Zodarion rubidum, and araneophagous Nops aff. variabilis and Palpimanus orientalis. 3. Generalists captured more prey, exploited each item of prey for a significantly shorter time, and had a shorter foraging pause than was the case for specialists. Generalists also gained significantly less relative amount of prey mass than did specialists. 4. Second, the study compared the prey DNA degradation rate in the gut of generalists and specialists by means of PCR. The degradation rate was not significantly different between specialists and generalists: the detectability half‐life was estimated to exist for 14.3 days after feeding. 5. This study shows that the feeding strategies of cursorial generalist and obligatory specialist spiders are different. Obligatory specialists have evolved a feeding strategy that is based on thorough exploitation of a few large prey, whereas generalists have evolved a strategy that is based on short exploitation of multiple small items of prey.

Parasitoid wasps of the Polysphincta genus-group are highly specialised on their spider hosts, and most of them are known to manipulate their hosts into building a special web in which the parasitoid pupates. Trophic niche and the plasticity of host use were investigated in the koinobiont parasitoid Zatypota kauros Gauld from Queensland, Australia. We found that Z. kauros attacks spider hosts from different families, each differing widely in their web-building behaviours, which makes it unique in the breadth of its host range. Molecular analyses revealed that the taxon Z. kauros contains three divergent mitochondrial lineages. Lineage A was associated exclusively with spiders of the genus Anelosimus (Theridiidae), which builds tangle webs; lineage B was associated with the genus Cyrtophora (Araneidae), which weaves tent webs; and lineage C was associated with a broad range of hosts, including spiders of both the families Araneidae and Theridiidae. Unique host manipulations could be observed in the web-building behaviours of the different host groups. Nevertheless, nuclear data from two ribosomal genes and three introns did not add any support to the existence of different evolutionary lineages, nor did they coincide with the different host groups. The partial correspondence of mitochondrial lineage and host use, together with an apparent mito-nuclear conflict might indicate maternal effects or very recent and/or incomplete speciation in this taxon. Given their wide host range and intriguing interactions with their hosts, the Z. kauros complex represents a promising system for studying parasitoid specialisation and its potential impact on speciation.

The present study was a 4-week randomized trial to assess the efficacy and safety of sitagliptin, a dipeptidyl-peptidase-4 inhibitor, in persistent or recurring type 2 diabetes after Roux-en-Y gastric bypass surgery (RYGB). Participants (n = 32) completed a mixed meal test (MMT) and self-monitoring of plasma glucose (SMPG) before and 4 weeks after randomization to either sitagliptin 100 mg daily or placebo daily. Questionnaires were administered to assess gastrointestinal discomfort. Outcome variables were glucose, active glucagon-like peptide-1 and β-cell function during the MMT, and glucose levels during SMPG. Age (56.3 ± 8.2 years), body mass index (34.4 ± 6.7 kg/m2 ), glycated haemoglobin (7.21 ± 0.77%), diabetes duration (12.9 ± 10.0 years), years since RYGB (5.6 ± 3.3 years) and β-cell function did not differ between the placebo and sitagliptin groups at pre-intervention. Sitagliptin was well tolerated, decreased postprandial glucose levels during the MMT (from 8.31 ± 1.92 mmol/L to 7.67 ± 1.59 mmol/L, P = 0.03) and mean SMPG levels, but had no effect on β-cell function. In patients with diabetes and mild hyperglycemia after RYGB, a short course of sitagliptin provided a small but significant glucose-lowering effect, with no identified improvement in β-cell function.

Water-in-oil (w/o) emulsions are used as a cellular model because of their unique cell-like architecture. Previous works showed the capability of eukaryotic-cell-sized w/o droplets (5-50 μm) to support protein synthesis efficiently; however data about smaller w/o compartments (

Objective Our aim is to evaluate if and how neuropsychiatric symptoms (NPS) of dementia influence the management and disposition of older adults who present to emergency care settings. Methods This is a retrospective cohort study that involved the medical and psychiatric emergency departments of a tertiary academic medical center. Participants included patients ≥65 years of age with dementia who presented between 1 February 2012 and 16 July 2014 (n = 347). Subjects with documented NPS (n = 78) were compared with a group of subjects without documented NPS (n = 78) randomly selected from the overall group with dementia. The groups with and without NPS were compared on demographic, clinical, management, and disposition characteristics. Results Patients with NPS were more likely to have additional diagnostic testing performed and receive psychotropic medications including benzodiazepines and antipsychotics. Significantly fewer patients with NPS (59.0%) returned to their original setting from the emergency department than patients without NPS (76.9%). Among patients with NPS, those who had a motor disturbance were more likely to receive psychotropic medications than patients who did not have a motor disturbance. Depression/dysphoria, anxiety, disinhibition, irritability/lability, and motor disturbance were all associated with transfer from medical to psychiatric emergency department. Patients with depression/dysphoria or anxiety were more likely to be psychiatrically hospitalized. Conclusions There are significant differences in the management of dementia with and without NPS in the emergency room setting. Developing and implementing successful methods to manage NPS in the emergency department and outpatient setting could potentially lead to less emergent psychotropic administration and reduce hospitalizations. Copyright © 2016 John Wiley & Sons, Ltd.

1. We assessed the changes in abundance and community composition of native species of coccinellids (Coleoptera: Coccinellidae) on deciduous trees that occurred between 1970s and 2010s, in the Czech Republic. 2. As the composition of adult communities varies with host plant and season, coccinellids were sampled in May–June from Acer, Betula and Tilia trees using a standardised sweeping method. This was done before (1976–1986) and after (2011–2014) the arrival of Harmonia axyridis in 2006, with interim samples from a period immediately before it arrived in the Czech Republic (2002–2006). 3. Twenty-one native species were identified in the total sample of 2674 adults. The abundance of Adalia bipunctata, Coccinella quinquepunctata and Propylea quatuordecimpunctata decreased over the whole period sampled. Declines in abundance of these species were already evident prior to the arrival of H.axyridis. Recent declines in Adalia decempunctata and Calvia quatuordecimguttata followed the arrival H. axyridis. Their abundance was increasing prior to the arrival of H. axyridis, but decreased following its invasion and the latter species might have affected their decline. The abundance of only one species, Calvia decemguttata, increased. Although the abundance of many species decreased and the frequency of some species varied, the diversity of native coccinellid populations (Shannon index) was similar over the 40 years of this study. 4. The changes in species composition can in part be attributed to H. axyridis, the role of other factors (e.g. climate change, habitat degradation) in the long-term fluctuations in abundance of coccinellids should be considered in future assessments.