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1.
Behav Processes ; 157: 540-546, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29870799

RESUMEN

Human-induced alterations of ecosystems and environmental conditions often lead to changes in the geographical range of plants and animals. While modelling exercises may contribute to understanding such dynamics at large spatial scales, they rarely offer insights into the mechanisms that prompt the process at a local scale. Savi's pipistrelle (Hypsugo savii) is a vespertilionid bat widespread throughout the Mediterranean region. The species' recent range expansion towards northeastern Europe is thought to be induced by urbanization, yet no study actually tested this hypothesis, and climate change is a potential alternative driver. In this radio-telemetry study, set in the Vesuvius National Park (Campania region, Southern Italy) we provide insights into the species' thermal physiology and foraging ecology and investigate their relationships with potential large-scale responses to climate, and land use changes. Specifically, we test whether H. savii i) exploits urbanisation by selecting urban areas for roosting and foraging, and ii) tolerates heatwaves (a proxy for thermophily) through a plastic use of thermoregulation. Tolerance to heatwaves would be consistent with the observation that the species' geographic range is not shifting but expanding northwards. Tracked bats roosted mainly in buildings but avoided urban habitats while foraging, actively selecting non-intensive farmland and natural wooded areas. Hypsugo H. savii showed tolerance to heat, reaching the highest body temperature ever recorded for a free-ranging bat (46.5 °C), and performing long periods of overheating. We conclude that H. savii is not a strictly synurbic species because it exploits urban areas mainly for roosting, and avoids them for foraging: this questions the role of synurbization as a range expansion driver. On the other hand, the species' extreme heat tolerance and plastic thermoregulatory behaviour represent winning traits to cope with heatwaves typical of climate change-related weather fluctuations.


Asunto(s)
Regulación de la Temperatura Corporal/fisiología , Quirópteros/fisiología , Ecosistema , Fenómenos de Retorno al Lugar Habitual/fisiología , Animales , Conducta Alimentaria , Femenino , Italia , Masculino , Telemetría , Letargo/fisiología , Urbanización
2.
Ecol Evol ; 7(14): 5310-5321, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28770069

RESUMEN

In summer, many temperate bat species use daytime torpor, but breeding females do so less to avoid interferences with reproduction. In forest-roosting bats, deep tree cavities buffer roost microclimate from abrupt temperature oscillations and facilitate thermoregulation. Forest bats also switch roosts frequently, so thermally suitable cavities may be limiting. We tested how barbastelle bats (Barbastella barbastellus), often roosting beneath flaking bark in snags, may thermoregulate successfully despite the unstable microclimate of their preferred cavities. We assessed thermoregulation patterns of bats roosting in trees in a beech forest of central Italy. Although all bats used torpor, females were more often normothermic. Cavities were poorly insulated, but social thermoregulation probably overcomes this problem. A model incorporating the presence of roost mates and group size explained thermoregulation patterns better than others based, respectively, on the location and structural characteristics of tree roosts and cavities, weather, or sex, reproductive or body condition. Homeothermy was recorded for all subjects, including nonreproductive females: This probably ensures availability of a warm roosting environment for nonvolant juveniles. Homeothermy may also represent a lifesaver for bats roosting beneath loose bark, very exposed to predators, because homeothermic bats may react quickly in case of emergency. We also found that barbastelle bats maintain group cohesion when switching roosts: This may accelerate roost occupation at the end of a night, quickly securing a stable microclimate in the newly occupied cavity. Overall, both thermoregulation and roost-switching patterns were satisfactorily explained as adaptations to a structurally and thermally labile roosting environment.

3.
BMC Infect Dis ; 17(1): 302, 2017 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-28438138

RESUMEN

BACKGROUND: A number of biomarkers have been studied for the diagnosis of sepsis in paediatrics, but no gold standard has been identified. Procalcitonin (PCT) was demonstrated to be an accurate biomarker for the diagnosis of sepsis in adults and showed to be promising in paediatrics. Our study reviewed the diagnostic accuracy of PCT as an early biomarker of sepsis in neonates and children with suspected sepsis. METHODS: A comprehensive literature search was carried out in Medline/Pubmed, Embase, ISI Web of Science, CINAHL and Cochrane Library, for studies assessing PCT accuracy in the diagnosis of sepsis in children and neonates with suspected sepsis. Studies in which the presence of infection had been confirmed microbiologically or classified as "probable" by chart review were included. Studies comparing patients to healthy subjects were excluded. We analysed data on neonates and children separately. Our primary outcome was the diagnostic accuracy of PCT at the cut-off of 2-2.5 ng/ml, while as secondary outcomes we analysed PCT cut-offs <2 ng/ml and >2.5 ng/ml. Pooled sensitivities and specificities were calculated by a bivariate meta-analysis and heterogeneity was graphically evaluated. RESULTS: We included 17 studies, with a total of 1408 patients (1086 neonates and 322 children). Studies on neonates with early onset sepsis (EOS) and late onset sepsis (LOS) were grouped together. In the neonatal group, we calculated a sensitivity of 0.85, confidence interval (CI) (0.76; 0.90) and specificity of 0.54, CI (0.38; 0.70) at the PCT cut-off of 2.0-2.5 ng/ml. In the paediatric group it was not possible to undertake a pooled analysis at the PCT cut-off of 2.0-2.5 ng/ml, due to the paucity of the studies. CONCLUSIONS: PCT shows a moderate accuracy for the diagnosis of sepsis in neonates with suspected sepsis at the cut-off of 2.0-2.5 ng/ml. More studies with high methodological quality are warranted, particularly in neonates, studies considering EOS and LOS separately are needed to improve specificity. TRIAL REGISTRATION: PROSPERO Identifier: CRD42016033809 . Registered 30 Jan 2016.


Asunto(s)
Calcitonina/sangre , Sepsis/diagnóstico , Biomarcadores/sangre , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sepsis/microbiología
4.
Ital J Pediatr ; 42: 44, 2016 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-27116911

RESUMEN

BACKGROUND: Differential diagnosis between sepsis and non-infectious inflammatory disorders demands improved biomarkers. Soluble Triggering Receptor Expression on Myeloid cells (sTREM-1) is an activating receptor whose role has been studied throughout the last decade. We performed a systematic review to evaluate the accuracy of plasma sTREM-1 levels in the diagnosis of sepsis in children with Systemic Inflammatory Response Syndrome (SIRS). METHODS: A literature search of PubMed, Cochrane Central Register of Controlled Trials, Cumulative Index to Nursing and Allied Health Literature (CINAHL) and ISI Web of Knowledge databases was performed using specific search terms. Studies were included if they assessed the diagnostic accuracy of plasma sTREM-1 for sepsis in paediatric patients with SIRS. Data on sensitivity, specificity, positive predictive value, negative predictive value, area under receiver operating characteristic curve were extracted. The methodological quality of each study was assessed using a checklist based on the Quality Assessment Tool for Diagnostic Accuracy Studies. RESULTS: Nine studies comprising 961 patients were included, four of which were in newborns, three in children and two in children with febrile neutropenia. Some data from single studies support a role of sTREM-1 as a diagnostic tool in pediatric sepsis, but cannot be considered conclusive, because a quantitative synthesis was not possible, due to heterogeneity in studies design. CONCLUSIONS: This systematic review suggests that available data are insufficient to support a role for sTREM in the diagnosis and follow-up of paediatric sepsis.


Asunto(s)
Glicoproteínas de Membrana/sangre , Células Mieloides , Receptores Inmunológicos/sangre , Síndrome de Respuesta Inflamatoria Sistémica/diagnóstico , Biomarcadores/sangre , Niño , Diagnóstico Diferencial , Humanos , Síndrome de Respuesta Inflamatoria Sistémica/sangre , Receptor Activador Expresado en Células Mieloides 1
5.
Pediatr Nephrol ; 29(11): 2229-33, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25037864

RESUMEN

BACKGROUND: Chronic granulomatous disease (CGD) is a primary immunodeficiency resulting from the absence or malfunction of oxidative mechanism in phagocytic cells. The disease is due to a mutation in one of four genes that encode subunits of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. Affected patients experience severe infections and granuloma formation due to exuberant inflammatory responses. Some evidence suggests that eosinophilic cystitis (EC) is included in the spectrum of inflammatory manifestations. EC is an inflammatory disease, rare in childhood, which may require different, nonstandardized therapeutic approaches, ranging from antihistamines to cyclosporine. CASE-DIAGNOSIS/TREATMENT: Herein we describe the cases of two CGD patients with CGD who experienced EC during hospitalization for a severe infection. CONCLUSIONS: EC in immunocompetent children seems to have a self-limiting course, unlike in CGD patients, in whom it presents a prolonged and recurrent course. We focus on the effective therapy administered to our patients with CGD and review the corresponding literature.


Asunto(s)
Cistitis/complicaciones , Cistitis/terapia , Enfermedad Granulomatosa Crónica/complicaciones , Absceso Encefálico/complicaciones , Absceso Encefálico/terapia , Preescolar , Eosinófilos/patología , Fiebre/complicaciones , Enfermedad Granulomatosa Crónica/genética , Humanos , Infecciones/complicaciones , Enfermedades Pulmonares/complicaciones , Masculino , Infecciones por Salmonella/complicaciones , Salmonella typhimurium
7.
Case Rep Pediatr ; 2013: 735108, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23862092

RESUMEN

X-linked agammaglobulinemia (XLA) is a primary immunodeficiency of the humoral compartment, due to a mutation in the Bruton tyrosine kinase (BTK) gene, characterized by a severe defect of circulating B cells and serum immunoglobulins. Recurrent infections are the main clinical manifestations; although they are especially due to encapsulated bacteria, a specific association with Campylobacter species has been reported. Here, we report the case of a boy with XLA who presented with relapsing Campylobacter jejuni systemic infections. His clinical history supports the hypothesis of the persistence of C. jejuni in his intestinal tract. Indeed, as previously reported, XLA patients may become chronic intestinal carriers of Campylobacter, even in absence of symptoms, with an increased risk of relapsing bacteraemia. The humoral defect is considered to be crucial for this phenomenon, as well as the difficulties to eradicate the pathogen with an appropriate antibiotic therapy; drug resistance is raising in Campylobacter species, and the appropriate duration of treatment has not been established. C. jejuni should always be suspected in XLA patients with signs and symptoms of systemic infection, and treatment should be based on antibiogram to assure the eradication of the pathogen.

8.
Nat Sci Sleep ; 5: 77-85, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23788845

RESUMEN

The correlation and/or comorbidity between sleep disorders and headache has been reported in numerous studies, but the exact nature of the association between headache, disordered sleep, and underlying mechanisms remains poorly understood. The bidirectional association between sleep and headache is mediated by a temporal link (headache occurs during sleep, after sleep, and in relationship with sleep stages), by a quantitative relationship (excess, lack, bad quality, short duration of sleep may trigger headache), and by a reciprocal connection (headache may cause sleep disruption and may be associated with several sleep disturbances). This association is most evident for primary headache disorders, especially in childhood. A congenital alteration of neurotransmitter pathways (serotoninergic and dopaminergic) might predispose individuals to both disorders, presenting as sleep-wake rhythm disorder in infancy or as headache disorder later in childhood, as result of this neurotransmitter imbalance. Clinicians should be aware that a complete clinical evaluation of childhood headache includes a careful sleep history, taking into account that the treatment of sleep disturbances could lead to an improvement of headache symptoms and vice versa.

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