347 research outputs found

    Direct-acting antivirals and visceral leishmaniasis: A case report

    Get PDF
    Background: Visceral leishmaniasis is a vector-borne parasitic disease caused by protozoa belonging to the genus Leishmania. The clinical presentation of visceral leishmaniasis strictly depends on the host immunocompetency, whereas depressive conditions of the immune system impair the capability to resolve the infection and allow reactivation from sites of latency of the parasite. Case presentation: We describe a case of visceral leishmaniasis (VL) that occurred in a patient with chronic hepatitis C treated with direct-acting antiviral drugs (DAA). The hypothesized mechanism is the alteration of protective inflammation mechanisms secondary to DAA therapy. Downregulation of type II and III IFNs, their receptors, which accompany HCV clearance achieved during treatment with sofosbuvir and ribavirin might have a negative impact on a risk for reactivation of a previous Leishmania infection. We know indeed that IFN-\u3b3 is important to enhance killing mechanisms in macrophages, which are the primary target cells of Leishmania. Conclusion: Since VL is endemic in Sicily as well as in other countries of the Mediterranean basin, physicians should be aware of the possible unmasking of cryptic Leishmania infection by DAAs

    Rethinking recognition: social context in adult life rather than early experience shapes recognition in a social wasp

    Get PDF
    Social recognition represents the foundation of social living. To what extent social recognition is hard-wired by early-life experience or flexible and influenced by social context of later life stages is a crucial question in animal behaviour studies. Social insects have represented classic models to investigate the subject, and the acknowledged idea is that relevant information to create the referent template for nest-mate recognition (NMR) is usually acquired during an early sensitive period in adult life. Experimental evidence, however, highlighted that other processes may also be at work in creating the template and that such a template may be updated during adult life according to social requirements. However, currently, we lack an ad hoc experiment testing the alternative hypotheses at the basis of NMR ontogeny in social insects. Thus, to investigate the mechanisms underlying the ontogeny of NMR in Polistes wasps, a model genus in recognition studies, and their different role in determining recognition abilities, we subjected Polistes dominula workers to different olfactory experiences in different phases of their life before inserting them into the social environment of a novel colony and testing them in recognition bioassays. Our results show that workers develop their NMR abilities based on their social context rather than through pre-imaginal and early learning or self-referencing. Our study demonstrates that the social context represents the major component shaping recognition abilities in a social wasp, therefore shedding new light on the ontogeny of recognition in paper wasps and prompting the reader to rethink about the traditional knowledge at the basis of the recognition in social insects. This article is part of the theme issue 'Signal detection theory in recognition systems: from evolving models to experimental tests'

    The effect of exposure to low frequency electromagnetic fields (EMF) as an integral part of the housing system on anxiety-related behaviour, cognition and welfare in two strains of laboratory mouse.

    Get PDF
    Electromagnetic field (EMF) technology has the potential to improve scientific data capture and welfare assessment by allowing automated data collection from individual cages. How- ever, it is important to determine any impact that a new technology itself may have on animal welfare, and previous studies have found contrasting results of EMF on laboratory rodent anxiety-like behaviour and cognition. We therefore investigated whether there was an effect of low frequency EMF experienced continuously over a six-week period, as an integral part of the animal housing system, on measures of mouse anxiety-related behaviour, cognition and welfare. We housed mice (N = 80) of two strains (BALB/cAnNCrl and C57BL/6NCrl) separately in Individually Ventilated Cages (IVCs) in groups of four, either with the EMF plate turned ‘on’ or ‘off’ (n = 5). Some measures, e.g. food and water utilisation, were col- lected at regular intervals, whereas measures of anxiety-like behaviour (e.g. open field test) and cognitive performance (novel-object recognition test) were collected only at the end of the study. We found expected strong strain differences in most measures, e.g. latency to leave the starting square in an open field test, with C57BL/6NCrl mice moving away sooner, and interactions between strain and time for those measures recorded at more than one time point, e.g. significant weight gain over time for both strains, but with BALB/cAnNCrl mice weighing more. However, we found no significant effects of treatment (EMF ‘on’/‘off’) for any of the measures collected. These results indicate that, for the measures recorded here, there was no measurable impact on the behaviour and welfare of low frequency EMF exposure experienced continuously over a six-week period. Housing systems that include EMF monitoring technology may therefore be suitable for use without influencing either ani- mal welfare or scientific outcomes

    Hornets and Honey Bees: A Coevolutionary Arms Race between Ancient Adaptations and New Invasive Threats

    Get PDF
    Hornets and honey bees have a long history of coevolution resulting in a plethora of captivating adaptations and counteradaptations between predator and prey. From simple physiological mechanisms to complex behavioral strategies, some Vespa hornets have specialized in hunting honey bees, while the latter have put in place effective defenses to counteract their attack. Both hornets and honey bees have evolved the ability to detect the odors and the pheromones emitted by the other to locate the prey or to spot foraging predators. Hornets often rely on their bigger size, heavily armored body and destructive attacks, while honey bees differentiated collective defense responses finely coordinated to deter or kill the hornet menace. However, when new species of hornets and honey bees come into contact, the absence of coevolution can have a heavy impact on the defenseless bees. The evolutionary arms race between hornets and honey bees provides not only compelling examples of adaptations and counteradaptations between predator and prey, but could also represent a starting point for the development of effective and sustainable strategies to protect honey bees and beekeeping activities and to control invasive alien species of hornets

    Competition between the native and the introduced hornets Vespa crabro and Vespa velutina: A comparison of potentially relevant life-history traits

    Get PDF
    1. Invasive alien species are a major threat to biodiversity. In addition to predation and parasitism, native species might suffer from competition when invasive alien species occupy a similar ecological niche. 2. This study focused on the potential interspecific interaction between two hornets: the Asian yellow‐legged hornet, Vespa velutina, a high‐concern invasive alien species recently arrived in Europe; and the native European hornet, Vespa crabro. The two species share a similar ecological niche and V. velutina is rapidly expanding across Europe, which suggests that V. crabro might suffer from competition. 3. Under laboratory‐controlled conditions, two life‐history traits that might cause the two species to compete were investigated: (i) the ability of workers to find food sources and their flexibility in exploiting them (through individual food item choice tests and exploration assays); and (ii) the worker resistance to pathogens (through immune challenge tests). 4. The results show that trophic preference of both species highly overlaps, with a marked dietary preference for honeybees compared with other insect prey and non‐prey protein items. No differences were observed in the exploratory behaviour of both species. Finally, constitutive antibacterial activity was greater in workers of the native species than in workers of the invasive hornet. 5. This laboratory study provides a first assessment under controlled conditions of the factors affecting competition between workers of two hornet species and proposes a framework to assess, in wild contexts, the magnitude of the competition and the impact of the introduced V. velutina on the native V. crabro

    Walk your talk: Real-world adherence to guidelines on the use of MRI in multiple sclerosis

    Get PDF
    (1) Although guidelines about the use of MRI sequences for Multiple Sclerosis (MS) diagnosis and follow-up are available, variability in acquisition protocols is not uncommon in everyday clinical practice. The aim of this study was to evaluate the real-world application of MS imaging guidelines in different settings to clarify the level of adherence to these guidelines. (2) Via an on-line anonymous survey, neuroradiologists (NR) were asked about MRI protocols and parameters routinely acquired when MS patients are evaluated in their center, both at diagnosis and followup. Furthermore, data about report content and personal opinions about emerging neuroimaging markers were also retrieved. (3) A total of 46 participants were included, mostly working in a hospital or university hospital (80.4%) and with more than 10 years of experience (47.9%). We found a relatively good adherence to the suggested MRI protocols regarding the use of T2-weighted sequences, although almost 10% of the participants routinely acquired 2D sequences with a slice thickness superior to 3 mm. On the other hand, a wider degree of heterogeneity was found regarding gadolinium administration, almost routinely performed at follow-up examination (87.0% of cases) in contrast with the current guidelines, as well as a low use of a standardized reporting system (17.4% of cases). (4) Although the MS community is getting closer to a standardization of MRI protocols, there is still a relatively wide heterogeneity among NR, with particular reference to contrast administration, which must be overcome to guarantee an adequate quality of patients’ care in MS

    Walk your talk: Real-world adherence to guidelines on the use of MRI in multiple sclerosis

    Get PDF
    (1) Although guidelines about the use of MRI sequences for Multiple Sclerosis (MS) diagnosis and follow-up are available, variability in acquisition protocols is not uncommon in everyday clinical practice. The aim of this study was to evaluate the real-world application of MS imaging guidelines in different settings to clarify the level of adherence to these guidelines. (2) Via an on-line anonymous survey, neuroradiologists (NR) were asked about MRI protocols and parameters routinely acquired when MS patients are evaluated in their center, both at diagnosis and followup. Furthermore, data about report content and personal opinions about emerging neuroimaging markers were also retrieved. (3) A total of 46 participants were included, mostly working in a hospital or university hospital (80.4%) and with more than 10 years of experience (47.9%). We found a relatively good adherence to the suggested MRI protocols regarding the use of T2-weighted sequences, although almost 10% of the participants routinely acquired 2D sequences with a slice thickness superior to 3 mm. On the other hand, a wider degree of heterogeneity was found regarding gadolinium administration, almost routinely performed at follow-up examination (87.0% of cases) in contrast with the current guidelines, as well as a low use of a standardized reporting system (17.4% of cases). (4) Although the MS community is getting closer to a standardization of MRI protocols, there is still a relatively wide heterogeneity among NR, with particular reference to contrast administration, which must be overcome to guarantee an adequate quality of patients' care in MS
    • 

    corecore