62 research outputs found

    La risposta di difesa degli organismi agli insetticidi: dall’ecologia dello stress al controllo di artropodi vettori

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    Tra i principali argomenti di studio della biologia vi sono i meccanismi con cui le cellule e gli organismi sono in grado di mantenere l'omeostasi in un ambiente avverso, ricco di stress chimici e fisici. “L’obbligo” di sopravvivenza che guida ogni organismo quando viene esposto ad agenti tossici, come sostanze chimiche tossiche endogene o composti xenobiotici, ha portato all’evoluzione di una serie di famiglie di geni e di pathways che, nell’insieme, prendono il nome di "defensoma chimico". Questa rete di difesa integrata, che permette ad ogni organismo di avvertire, trasformare ed eliminare le sostanze chimiche tossiche, è stata recentemente sottoposta ad approfondite indagini, in particolare modo negli artropodi, in merito alla loro grande importanza economica, ambientale e medico-veterinaria. Considerato il ruolo ancora oggi svolto dai composti chimici, come strumento per il controllo di numerosi pests, l'insorgenza della resistenza metabolica contro diversi insetticidi rappresenta un problema dal punto di vista del controllo d’insetti dannosi, da cui deriva il rischio di un’intensificazione nell’utilizzo degli stessi insetticidi, quindi problematiche ecologiche. Tra i principali meccanismi molecolari, appartenenti al complesso del defensoma chimico, vi sono gli ABC trasportatori, proteine integrali di membrana, atte a disintossicare la cellula da diversi composti nocivi con cui questa entra in contatto. Essi agiscono come prima linea di difesa nelle cellule esposte a uno stress chimico, trasportando le molecole tossiche all’esterno della cellula e riducendone di conseguenza la concentrazione intracellulare necessaria per provocare il danno all’organismo. Gli ABC trasportatori, ben noti e ampiamente indagati in altri animali, hanno suscitato interesse per quanto riguarda gli artropodi solo negli ultimi anni. Al momento, le indagini svolte hanno chiarito solo in parte il ruolo svolto da questi trasportatori nel complesso del defensoma, rimangono quindi diversi interrogativi irrisolti. Questo progetto di dottorato si pone come primo obiettivo quello d’indagare approfonditamente il ruolo di queste proteine di detossificazione e la loro risposta, in termini di espressione genica, all’insetticida di sintesi piretroide, permetrina, in due specie di zanzara vettrici di malaria, Anopheles stephensi e Anopheles gambiae sensu stricto. Una volta determinati i geni maggiormente coinvolti nei processi di detossificazione, si è posto come secondo obiettivo quello di sviluppare sistemi d’inibizione dell’espressione genica al fine di garantire una concentrazione adeguata dell’insetticida, in sede intracellulare, da cui deriverebbero sia un’intensificazione dell’azione dell’insetticida, sia la mancata realizzazione di condizioni di sotto-dosaggio, potenzialmente favorevoli all’insorgenza di resistenze. Per quanto riguarda An. stephensi, le ricerche hanno potuto trovare una base solida ed un background di confronto in lavori precedenti, in cui il grado di attivazione di un selezionato “pacchetto” di geni era già stato evidenziato in larve, in risposta al piretroide, a diversi tempi. Nel presente studio dunque abbiamo voluto indagare il pattern d’espressione degli stessi geni (sei, appartenenti alle sottofamiglie ABCB, ABCC, ABCG), correlato al tasso di mortalità, nello stadio adulto di An. stephensi, maschi e femmine, sottoposti al trattamento con permetrina. Le diverse pressioni selettive alle quali le molteplici forme sono sottoposte potrebbero influire sui valori e la dinamicità di espressione dei trasportatori. In An. gambiae s.s. si è voluto analizzare, per la prima volta, il coinvolgimento degli stessi geni in larve, tramite duplice approccio: induzione ed inibizione aspecifica. E’ stato quindi evidenziato il pattern di espressione nel tempo di cinque geni ABC (sottofamiglie ABCB, ABCC, ABCG) dopo induzione sia con sola permetrina, sia in combinazione con un inibitore aspecifico dei trasportatori ABC (verapamil). Le indagini svolte nell’ambito del primo obiettivo hanno permesso di identificare il trasportatore ABCG4 come target promettente ai fini di un’inibizione dei meccanismi di difesa, sia in An. stephensi che in An. gambiae. Il secondo obiettivo è stato perseguito attraverso esperimenti su larve di An. stephensi. Una prima fase di studio è consistita nella realizzazione di saggi d’inibizione attraverso siRNA specie- e sequenza-specifico. I risultati ottenuti hanno consolidato l’ipotesi di un marcato coinvolgimento di ABCG4 come prima difesa contro la permetrina nelle larve di An. stephensi. La seconda fase dello studio d’inibizione ha previsto l’utilizzo di un diverso tipo di oligonucleotide antisenso (Vivo-Morpholino), caratterizzato da una maggiore stabilità ed efficacia rispetto al siRNA e dunque più adatto per un eventuale utilizzo in campo. Maggiormente rispetto al siRNA, la molecola di Vivo-Morpholino ha potenziato l’azione della permetrina, permettendo di ottenere la medesima mortalità larvale in presenza di dosi ridotte d’insetticida. In conclusione, il lavoro svolto, oltre a determinare il quadro di espressione di geni coinvolti nella detossificazione in due specie di zanzare malariche, ha percorso i primi passi verso la possibilità di sfruttare l'inibizione dell'espressione di un ABC trasportatore, per la progettazione di nuovi approcci di controllo del vettore, al fine di ridurre le dosi d’insetticidi chimici impiegati. Sarà dunque opportuno effettuare indagini più approfondite, per lo sviluppo di larvicidi e di sistemi di delivery altamente ecocompatibili e dunque fruibili per future applicazioni in campo

    Feasibility and Acceptability of a Real-Time Telerehabilitation Intervention for Children and Young Adults with Acquired Brain Injury During the COVID-19 Pandemic: An Experience Report

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    This study examined the feasibility and acceptability of a telerehabilitation intervention during the COVID-19 pandemic in a sample of children and young adults with Acquired Brain Injury (ABI). Thirteen patients and/or their families agreed to participate in the speech and neuropsychological telerehabilitation sessions. The treatment was synchronous, patient centered and aimed at improving specific abilities. Sessions were held twice a week over a 10-week period. Two questionnaires were completed both by parents and therapists to assess feasibility and acceptability. Neither technical issues nor clinical obstacles were found. The quality of the therapeutic relationship played a key role in the intervention. Synchronous telerehabilitation provided several advantages both for patients and therapists. Moreover, the patient centered intervention eased the burden of the caregivers at a time of high stress. The real-time telerehabilitation treatments were deemed suitable for children and young adults with ABI. Further studies are needed to support the use of telerehabilitation as an integral part of their standard care

    Scalable software framework for real-time data processing in the railway environment

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    Background: Ticks are obligate haematophagous ectoparasites of vertebrates and frequently parasitize avian species that can carry them across continents during their long-distance migrations. Ticks may have detrimental effects on the health state of their avian hosts, which can be either directly caused by blood-draining or mediated by microbial pathogens transmitted during the blood meal. Indeed, ticks host complex microbial communities, including bacterial pathogens and symbionts. Midichloria bacteria (Rickettsiales) are widespread tick endosymbionts that can be transmitted to vertebrate hosts during the tick bite, inducing an antibody response. Their actual role as infectious/pathogenic agents is, however, unclear. Methods: We screened for Midichloria DNA African ticks and blood samples collected from trans-Saharan migratory songbirds at their arrival in Europe during spring migration. Results: Tick infestation rate was 5.7%, with most ticks belonging to the Hyalomma marginatum species complex. Over 90% of Hyalomma ticks harboured DNA of Midichloria bacteria belonging to the monophylum associated with ticks. Midichloria DNA was detected in 43% of blood samples of avian hosts. Tick-infested adult birds were significantly more likely to test positive to the presence of Midichloria DNA than non-infested adults and second-year individuals, suggesting a long-term persistence of these bacteria within avian hosts. Tick parasitism was associated with a significantly delayed timing of spring migration of avian hosts but had no significant effects on body condition, whereas blood Midichloria DNA presence negatively affected fat deposits of tick-infested avian hosts. Conclusions: Our results show that ticks effectively transfer Midichloria bacteria to avian hosts, supporting the hypothesis that they are infectious to vertebrates. Bird infection likely enhances the horizontal spread of these bacteria across haematophagous ectoparasite populations. Moreover, we showed that Midichloria and tick parasitism have detrimental non-independent effects on avian host health during migration, highlighting the complexity of interactions involving ticks, their vertebrate hosts, and tick-borne bacteria

    Why Are Outcomes Different for Registry Patients Enrolled Prospectively and Retrospectively? Insights from the Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF).

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    Background: Retrospective and prospective observational studies are designed to reflect real-world evidence on clinical practice, but can yield conflicting results. The GARFIELD-AF Registry includes both methods of enrolment and allows analysis of differences in patient characteristics and outcomes that may result. Methods and Results: Patients with atrial fibrillation (AF) and ≥1 risk factor for stroke at diagnosis of AF were recruited either retrospectively (n = 5069) or prospectively (n = 5501) from 19 countries and then followed prospectively. The retrospectively enrolled cohort comprised patients with established AF (for a least 6, and up to 24 months before enrolment), who were identified retrospectively (and baseline and partial follow-up data were collected from the emedical records) and then followed prospectively between 0-18 months (such that the total time of follow-up was 24 months; data collection Dec-2009 and Oct-2010). In the prospectively enrolled cohort, patients with newly diagnosed AF (≤6 weeks after diagnosis) were recruited between Mar-2010 and Oct-2011 and were followed for 24 months after enrolment. Differences between the cohorts were observed in clinical characteristics, including type of AF, stroke prevention strategies, and event rates. More patients in the retrospectively identified cohort received vitamin K antagonists (62.1% vs. 53.2%) and fewer received non-vitamin K oral anticoagulants (1.8% vs . 4.2%). All-cause mortality rates per 100 person-years during the prospective follow-up (starting the first study visit up to 1 year) were significantly lower in the retrospective than prospectively identified cohort (3.04 [95% CI 2.51 to 3.67] vs . 4.05 [95% CI 3.53 to 4.63]; p = 0.016). Conclusions: Interpretations of data from registries that aim to evaluate the characteristics and outcomes of patients with AF must take account of differences in registry design and the impact of recall bias and survivorship bias that is incurred with retrospective enrolment. Clinical Trial Registration: - URL: http://www.clinicaltrials.gov . Unique identifier for GARFIELD-AF (NCT01090362)

    Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

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    Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

    Risk profiles and one-year outcomes of patients with newly diagnosed atrial fibrillation in India: Insights from the GARFIELD-AF Registry.

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    BACKGROUND: The Global Anticoagulant Registry in the FIELD-Atrial Fibrillation (GARFIELD-AF) is an ongoing prospective noninterventional registry, which is providing important information on the baseline characteristics, treatment patterns, and 1-year outcomes in patients with newly diagnosed non-valvular atrial fibrillation (NVAF). This report describes data from Indian patients recruited in this registry. METHODS AND RESULTS: A total of 52,014 patients with newly diagnosed AF were enrolled globally; of these, 1388 patients were recruited from 26 sites within India (2012-2016). In India, the mean age was 65.8 years at diagnosis of NVAF. Hypertension was the most prevalent risk factor for AF, present in 68.5% of patients from India and in 76.3% of patients globally (P < 0.001). Diabetes and coronary artery disease (CAD) were prevalent in 36.2% and 28.1% of patients as compared with global prevalence of 22.2% and 21.6%, respectively (P < 0.001 for both). Antiplatelet therapy was the most common antithrombotic treatment in India. With increasing stroke risk, however, patients were more likely to receive oral anticoagulant therapy [mainly vitamin K antagonist (VKA)], but average international normalized ratio (INR) was lower among Indian patients [median INR value 1.6 (interquartile range {IQR}: 1.3-2.3) versus 2.3 (IQR 1.8-2.8) (P < 0.001)]. Compared with other countries, patients from India had markedly higher rates of all-cause mortality [7.68 per 100 person-years (95% confidence interval 6.32-9.35) vs 4.34 (4.16-4.53), P < 0.0001], while rates of stroke/systemic embolism and major bleeding were lower after 1 year of follow-up. CONCLUSION: Compared to previously published registries from India, the GARFIELD-AF registry describes clinical profiles and outcomes in Indian patients with AF of a different etiology. The registry data show that compared to the rest of the world, Indian AF patients are younger in age and have more diabetes and CAD. Patients with a higher stroke risk are more likely to receive anticoagulation therapy with VKA but are underdosed compared with the global average in the GARFIELD-AF. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Improved risk stratification of patients with atrial fibrillation: an integrated GARFIELD-AF tool for the prediction of mortality, stroke and bleed in patients with and without anticoagulation.

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    OBJECTIVES: To provide an accurate, web-based tool for stratifying patients with atrial fibrillation to facilitate decisions on the potential benefits/risks of anticoagulation, based on mortality, stroke and bleeding risks. DESIGN: The new tool was developed, using stepwise regression, for all and then applied to lower risk patients. C-statistics were compared with CHA2DS2-VASc using 30-fold cross-validation to control for overfitting. External validation was undertaken in an independent dataset, Outcome Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). PARTICIPANTS: Data from 39 898 patients enrolled in the prospective GARFIELD-AF registry provided the basis for deriving and validating an integrated risk tool to predict stroke risk, mortality and bleeding risk. RESULTS: The discriminatory value of the GARFIELD-AF risk model was superior to CHA2DS2-VASc for patients with or without anticoagulation. C-statistics (95% CI) for all-cause mortality, ischaemic stroke/systemic embolism and haemorrhagic stroke/major bleeding (treated patients) were: 0.77 (0.76 to 0.78), 0.69 (0.67 to 0.71) and 0.66 (0.62 to 0.69), respectively, for the GARFIELD-AF risk models, and 0.66 (0.64-0.67), 0.64 (0.61-0.66) and 0.64 (0.61-0.68), respectively, for CHA2DS2-VASc (or HAS-BLED for bleeding). In very low to low risk patients (CHA2DS2-VASc 0 or 1 (men) and 1 or 2 (women)), the CHA2DS2-VASc and HAS-BLED (for bleeding) scores offered weak discriminatory value for mortality, stroke/systemic embolism and major bleeding. C-statistics for the GARFIELD-AF risk tool were 0.69 (0.64 to 0.75), 0.65 (0.56 to 0.73) and 0.60 (0.47 to 0.73) for each end point, respectively, versus 0.50 (0.45 to 0.55), 0.59 (0.50 to 0.67) and 0.55 (0.53 to 0.56) for CHA2DS2-VASc (or HAS-BLED for bleeding). Upon validation in the ORBIT-AF population, C-statistics showed that the GARFIELD-AF risk tool was effective for predicting 1-year all-cause mortality using the full and simplified model for all-cause mortality: C-statistics 0.75 (0.73 to 0.77) and 0.75 (0.73 to 0.77), respectively, and for predicting for any stroke or systemic embolism over 1 year, C-statistics 0.68 (0.62 to 0.74). CONCLUSIONS: Performance of the GARFIELD-AF risk tool was superior to CHA2DS2-VASc in predicting stroke and mortality and superior to HAS-BLED for bleeding, overall and in lower risk patients. The GARFIELD-AF tool has the potential for incorporation in routine electronic systems, and for the first time, permits simultaneous evaluation of ischaemic stroke, mortality and bleeding risks. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier for GARFIELD-AF (NCT01090362) and for ORBIT-AF (NCT01165710)

    Two-year outcomes of patients with newly diagnosed atrial fibrillation: results from GARFIELD-AF.

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    AIMS: The relationship between outcomes and time after diagnosis for patients with non-valvular atrial fibrillation (NVAF) is poorly defined, especially beyond the first year. METHODS AND RESULTS: GARFIELD-AF is an ongoing, global observational study of adults with newly diagnosed NVAF. Two-year outcomes of 17 162 patients prospectively enrolled in GARFIELD-AF were analysed in light of baseline characteristics, risk profiles for stroke/systemic embolism (SE), and antithrombotic therapy. The mean (standard deviation) age was 69.8 (11.4) years, 43.8% were women, and the mean CHA2DS2-VASc score was 3.3 (1.6); 60.8% of patients were prescribed anticoagulant therapy with/without antiplatelet (AP) therapy, 27.4% AP monotherapy, and 11.8% no antithrombotic therapy. At 2-year follow-up, all-cause mortality, stroke/SE, and major bleeding had occurred at a rate (95% confidence interval) of 3.83 (3.62; 4.05), 1.25 (1.13; 1.38), and 0.70 (0.62; 0.81) per 100 person-years, respectively. Rates for all three major events were highest during the first 4 months. Congestive heart failure, acute coronary syndromes, sudden/unwitnessed death, malignancy, respiratory failure, and infection/sepsis accounted for 65% of all known causes of death and strokes for <10%. Anticoagulant treatment was associated with a 35% lower risk of death. CONCLUSION: The most frequent of the three major outcome measures was death, whose most common causes are not known to be significantly influenced by anticoagulation. This suggests that a more comprehensive approach to the management of NVAF may be needed to improve outcome. This could include, in addition to anticoagulation, interventions targeting modifiable, cause-specific risk factors for death. CLINICAL TRIAL REGISTRATION: http://www.clinicaltrials.gov. Unique identifier: NCT01090362

    Proceedings of the Fifth Italian Conference on Computational Linguistics CLiC-it 2018

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    On behalf of the Program Committee, a very warm welcome to the Fifth Italian Conference on Computational Linguistics (CLiC-­‐it 2018). This edition of the conference is held in Torino. The conference is locally organised by the University of Torino and hosted into its prestigious main lecture hall “Cavallerizza Reale”. The CLiC-­‐it conference series is an initiative of the Italian Association for Computational Linguistics (AILC) which, after five years of activity, has clearly established itself as the premier national forum for research and development in the fields of Computational Linguistics and Natural Language Processing, where leading researchers and practitioners from academia and industry meet to share their research results, experiences, and challenges

    Insecticide Exposure Triggers a Modulated Expression of ABC Transporter Genes in Larvae of Anopheles gambiae s.s.

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    Insecticides remain a main tool for the control of arthropod vectors. The urgency to prevent the insurgence of insecticide resistance and the perspective to find new target sites, for the development of novel molecules, are fuelling the study of the molecular mechanisms involved in insect defence against xenobiotic compounds. In this study, we have investigated if ATP-binding cassette (ABC) transporters, a major component of the defensome machinery, are involved in defence against the insecticide permethrin, in susceptible larvae of the malaria vector Anopheles gambiae sensu stricto. Bioassays were performed with permethrin alone, or in combination with an ABC transporter inhibitor. Then we have investigated the expression profiles of five ABC transporter genes at different time points following permethrin exposure, to assess their expression patterns across time. The inhibition of ABC transporters increased the larval mortality by about 15-fold. Likewise, three genes were up-regulated after exposure to permethrin, showing different patterns of expression across the 48 h. Our results provide the first evidences of ABC transporters involvement in defence against a toxic in larvae of An. gambiae s.s. and show that the gene expression response is modulated across time, being continuous, but stronger at the earliest and latest times after exposure
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