41 research outputs found

    Reduced Leukocyte Infiltration in Absence of Eosinophils Correlates With Decreased Tissue Damage and Disease Susceptibility in ΔdblGATA Mice During Murine Neurocysticercosis

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    Neurocysticercosis (NCC) is one of the most common helminth parasitic diseases of the central nervous system (CNS) and the leading cause of acquired epilepsy worldwide. NCC is caused by the presence of the metacestode larvae of the tapeworm Taenia solium within brain tissues. NCC patients exhibit a long asymptomatic phase followed by a phase of symptoms including increased intra-cranial pressure and seizures. While the asymptomatic phase is attributed to the immunosuppressive capabilities of viable T. solium parasites, release of antigens by dying organisms induce strong immune responses and associated symptoms. Previous studies in T. solium-infected pigs have shown that the inflammatory response consists of various leukocyte populations including eosinophils, macrophages, and T cells among others. Because the role of eosinophils within the brain has not been investigated during NCC, we examined parasite burden, disease susceptibility and the composition of the inflammatory reaction in the brains of infected wild type (WT) and eosinophil-deficient mice (ΔdblGATA) using a murine model of NCC in which mice were infected intracranially with Mesocestoides corti, a cestode parasite related to T. solium. In WT mice, we observed a time-dependent induction of eosinophil recruitment in infected mice, contrasting with an overall reduced leukocyte infiltration in ΔdblGATA brains. Although, ΔdblGATA mice exhibited an increased parasite burden, reduced tissue damage and less disease susceptibility was observed when compared to infected WT mice. Cellular infiltrates in infected ΔdblGATA mice were comprised of more mast cells, and αβ T cells, which correlated with an abundant CD8+ T cell response and reduced CD4+ Th1 and Th2 responses. Thus, our data suggest that enhanced inflammatory response in WT mice appears detrimental and associates with increased disease susceptibility, despite the reduced parasite burden in the CNS. Overall reduced leukocyte infiltration due to absence of eosinophils correlates with attenuated tissue damage and longer survival of ΔdblGATA mice. Therefore, our study suggests that approaches to clear NCC will require strategies to tightly control the host immune response while eradicating the parasite with minimal damage to brain tissue

    Attenuated Response of Aged Mice to Respiratory Francisella novicida Is Characterized by Reduced Cell Death and Absence of Subsequent Hypercytokinemia

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    Pneumonia and pulmonary infections are major causes of mortality among the growing elderly population. Age associated attenuations of various immune parameters, involved with both innate and adaptive responses are collectively known as immune senescence. These changes are likely to be involved with differences in host susceptibility to disease between young and aged individuals.The objective of this study was to assess potential age related differences in the pulmonary host response in mice to the Gram-negative respiratory pathogen, Francisella novicida. We intranasally infected mice with F. novicida and compared various immune and pathological parameters of the pulmonary host response in both young and aged mice.We observed that 20% of aged mice were able to survive an intranasal challenge with F. novicida while all of their younger cohorts died consistently within 4 to 6 days post infection. Further experiments revealed that all of the aged mice tested were initially able to control bacterial replication in the lungs as well as at distal sites of replication compared with young mice. In addition, the small cohort of aged survivors did not progress to a severe sepsis syndrome with hypercytokinemia, as did all of the young adult mice. Finally, a lack of widespread cell death in potential aged survivors coupled with a difference in cell types recruited to sites of infection within the lung confirmed an altered host response to Francisella in aged mice

    Rapid dissemination of Francisella tularensis and the effect of route of infection

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    <p>Abstract</p> <p>Background</p> <p><it>Francisella tularensis </it>subsp. <it>tularensis </it>is classified as a Category A bioweapon that is capable of establishing a lethal infection in humans upon inhalation of very few organisms. However, the virulence mechanisms of this organism are not well characterized. <it>Francisella tularensis </it>subsp. <it>novicida</it>, which is an equally virulent subspecies in mice, was used in concert with a microPET scanner to better understand its temporal dissemination in vivo upon intranasal infection and how such dissemination compares with other routes of infection. Adult mice were inoculated intranasally with <it>F. tularensis </it>subsp. <it>novicida </it>radiolabeled with <sup>64</sup>Cu and imaged by microPET at 0.25, 2 and 20 hours post-infection.</p> <p>Results</p> <p><sup>64</sup>Cu labeled <it>F. tularensis </it>subsp. <it>novicida </it>administered intranasally or intratracheally were visualized in the respiratory tract and stomach at 0.25 hours post infection. By 20 hours, there was significant tropism to the lung compared with other tissues. In contrast, the images of radiolabeled <it>F. tularensis </it>subsp. <it>novicida </it>when administered intragastrically, intradermally, intraperitoneally and intravenouslly were more generally limited to the gastrointestinal system, site of inoculation, liver and spleen respectively. MicroPET images correlated with the biodistribution of isotope and bacterial burdens in analyzed tissues.</p> <p>Conclusion</p> <p>Our findings suggest that Francisella has a differential tissue tropism depending on the route of entry and that the virulence of Francisella by the pulmonary route is associated with a rapid bacteremia and an early preferential tropism to the lung. In addition, the use of the microPET device allowed us to identify the cecum as a novel site of colonization of <it>Francisella tularensis </it>subsp. <it>novicida </it>in mice.</p

    Incidence of first stroke and ethnic differences in stroke pattern in Bradford, UK: Bradford Stroke Study

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    Background: Information on ethnic disparities in stroke between White and Pakistani population in Europe is scarce. Bradford District has the largest proportion of Pakistani people in England; this provides a unique opportunity to study the difference in stroke between the two major ethnic groups. Aim: To determine the first-ever-stroke incidence and examine the disparities in stroke patterns between Whites and Pakistanis in Bradford. Methods: Prospective 12 months study consisting of 273,327 adults (≥18 years) residents. Stroke cases were identified by multiple overlapping approaches. Results: In the study period, 541 first-ever-strokes were recorded. The crude incidence rate was 198 per 100,000 person-years. Age adjusted-standardized rate to the World Health Organization world population of first-ever-stroke is 155 and 101 per 100,000 person-years in Pakistanis and Whites respectively. Four hundred and thirty-eight patients (81%) were Whites, 83 (15.3%) were Pakistanis, 11 (2%) were Indian and Bangladeshis, and 9 (1.7%) were of other ethnic origin. Pakistanis were significantly younger and had more obesity (p = 0.049), and diabetes mellitus (DM) (p = <0.001). They were less likely to suffer from atrial fibrillation (p = <0.001), be ex- or current smokers (p = <0.001), and drink alcohol above the recommended level (p = 0.007) compared with Whites. In comparison with Whites, higher rates of age-adjusted stroke (1.5-fold), lacunar infarction (threefold), and ischemic infarction due to large artery disease (twofold) were found in the Pakistanis. Conclusions: The incidence of first-ever-stroke is higher in the Pakistanis compared with the Whites in Bradford, UK. Etiology and vascular risk factors vary between the ethnic groups. This information should be considered when investigating stroke etiology, and when planning prevention and care provision to improve outcomes after stroke

    Development and validation of an electronic frailty index using routine primary care electronic health record data

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    Background: frailty is an especially problematic expression of population ageing. International guidelines recommend routine identification of frailty to provide evidence-based treatment, but currently available tools require additional resource. Objectives: to develop and validate an electronic frailty index (eFI) using routinely available primary care electronic health record data. Study design and setting: retrospective cohort study. Development and internal validation cohorts were established using a randomly split sample of the ResearchOne primary care database. External validation cohort established using THIN database. Participants: patients aged 65–95, registered with a ResearchOne or THIN practice on 14 October 2008. Predictors: we constructed the eFI using the cumulative deficit frailty model as our theoretical framework. The eFI score is calculated by the presence or absence of individual deficits as a proportion of the total possible. Categories of fit, mild, moderate and severe frailty were defined using population quartiles. Outcomes: outcomes were 1-, 3- and 5-year mortality, hospitalisation and nursing home admission. Statistical analysis: hazard ratios (HRs) were estimated using bivariate and multivariate Cox regression analyses. Discrimination was assessed using receiver operating characteristic (ROC) curves. Calibration was assessed using pseudo-R2 estimates. Results: we include data from a total of 931,541 patients. The eFI incorporates 36 deficits constructed using 2,171 CTV3 codes. One-year adjusted HR for mortality was 1.92 (95% CI 1.81–2.04) for mild frailty, 3.10 (95% CI 2.91–3.31) for moderate frailty and 4.52 (95% CI 4.16–4.91) for severe frailty. Corresponding estimates for hospitalisation were 1.93 (95% CI 1.86–2.01), 3.04 (95% CI 2.90–3.19) and 4.73 (95% CI 4.43–5.06) and for nursing home admission were 1.89 (95% CI 1.63–2.15), 3.19 (95% CI 2.73–3.73) and 4.76 (95% CI 3.92–5.77), with good to moderate discrimination but low calibration estimates. Conclusions: the eFI uses routine data to identify older people with mild, moderate and severe frailty, with robust predictive validity for outcomes of mortality, hospitalisation and nursing home admission. Routine implementation of the eFI could enable delivery of evidence-based interventions to improve outcomes for this vulnerable group

    Antipsychotic medication versus psychological intervention versus a combination of both in adolescents with first-episode psychosis (MAPS): a multicentre, three-arm, randomised controlled pilot and feasibility study

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    Background Evidence for the effectiveness of treatments in early-onset psychosis is sparse. Current guidance for the treatment of early-onset psychosis is mostly extrapolated from trials in adult populations. The UK National Institute for Health and Care Excellence has recommended evaluation of the clinical effectiveness and cost-effectiveness of antipsychotic drugs versus psychological intervention (cognitive behavioural therapy [CBT] and family intervention) versus the combination of these treatments for early-onset psychosis. The aim of this study was to establish the feasibility of a randomised controlled trial of antipsychotic monotherapy, psychological intervention monotherapy, and antipsychotics plus psychological intervention in adolescents with first-episode psychosis. Methods We did a multicentre pilot and feasibility trial according to a randomised, single-blind, three-arm, controlled design. We recruited participants from seven UK National Health Service Trust sites. Participants were aged 14–18 years; help-seeking; had presented with first-episode psychosis in the past year; were under the care of a psychiatrist; were showing current psychotic symptoms; and met ICD-10 criteria for schizophrenia, schizoaffective disorder, or delusional disorder, or met the entry criteria for an early intervention for psychosis service. Participants were assigned (1:1:1) to antipsychotics, psychological intervention (CBT with optional family intervention), or antipsychotics plus psychological intervention. Randomisation was via a web-based randomisation system, with permuted blocks of random size, stratified by centre and family contact. CBT incorporated up to 26 sessions over 6 months plus up to four booster sessions, and family intervention incorporated up to six sessions over 6 months. Choice and dose of antipsychotic were at the discretion of the treating consultant psychiatrist. Participants were followed up for a maximum of 12 months. The primary outcome was feasibility (ie, data on trial referral and recruitment, session attendance or medication adherence, retention, and treatment acceptability) and the proposed primary efficacy outcome was total score on the Positive and Negative Syndrome Scale (PANSS) at 6 months. Primary outcomes were analysed by intention to treat. Safety outcomes were reported according to as-treated status, for all patients who had received at least one session of CBT or family intervention, or at least one dose of antipsychotics. The study was prospectively registered with ISRCTN, ISRCTN80567433. Findings Of 101 patients referred to the study, 61 patients (mean age 16·3 years [SD 1·3]) were recruited from April 10, 2017, to Oct 31, 2018, 18 of whom were randomly assigned to psychological intervention, 22 to antipsychotics, and 21 to antipsychotics plus psychological intervention. The trial recruitment rate was 68% of our target sample size of 90 participants. The study had a low referral to recruitment ratio (around 2:1), a high rate of retention (51 [84%] participants retained at the 6-month primary endpoint), a high rate of adherence to psychological intervention (defined as six or more sessions of CBT; in 32 [82%] of 39 participants in the monotherapy and combined groups), and a moderate rate of adherence to antipsychotic medication (defined as at least 6 consecutive weeks of exposure to antipsychotics; in 28 [65%] of 43 participants in the monotherapy and combined groups). Mean scores for PANSS total at the 6-month primary endpoint were 68·6 (SD 17·3) for antipsychotic monotherapy (6·2 points lower than at randomisation), 59·8 (13·7) for psychological intervention (13·1 points lower than at randomisation), and 62·0 (15·9) for antipsychotics plus psychological intervention (13·9 points lower than at randomisation). A good clinical response at 6 months (defined as ≥50% improvement in PANSS total score) was achieved in four (22%) of 18 patients receiving antipsychotic monotherapy, five (31%) of 16 receiving psychological intervention, and five (29%) of 17 receiving antipsychotics plus psychological intervention. In as-treated groups, serious adverse events occurred in eight [35%] of 23 patients in the combined group, two [13%] of 15 in the antipsychotics group, four [24%] of 17 in the psychological intervention group, and four [80%] of five who did not receive any treatment. No serious adverse events were considered to be related to participation in the trial. Interpretation This trial is the first to show that a head-to-head clinical trial comparing psychological intervention, antipsychotics, and their combination is safe in young people with first-episode psychosis. However, the feasibility of a larger trial is unclear because of site-specific recruitment challenges, and amendments to trial design would be needed for an adequately powered clinical and cost-effectiveness trial that provides robust evidence

    The evolution of a Gondwanan collisional orogen: A structural and geochronological appraisal from the Southern Granulite Terrane, South India

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    Gondwana amalgamated along a suite of Himalayan-scale collisional orogens, the roots of which lace the continents of Africa, South America, and Antarctica. The Southern Granulite Terrane of India is a generally well-exposed, exhumed, Gondwana-forming orogen that preserves a record of the tectonic evolution of the eastern margin of the East African Orogen during the Ediacaran-Cambrian (circa 600–500 Ma) as central Gondwana formed. The deformation associated with the closure of the Mozambique Ocean and collision of the Indian and East African/Madagascan cratonic domains is believed to have taken place along the southern margin of the Salem Block (the Palghat-Cauvery Shear System, PCSS) in the Southern Granulite Terrane. Investigation of the structural fabrics and the geochronology of the high-grade shear zones within the PCSS system shows that the Moyar-Salem-Attur shear zone to the north of the PCSS system is early Paleoproterozoic in age and associated with dextral strike-slip motion, while the Cauvery shear zone (CSZ) to the south of the PCSS system can be loosely constrained to circa 740–550 Ma and is associated with dip-slip dextral transpression and north side-up motion.To the south of the proposed suture zone (the Cauvery shear zone), the structural fabrics of the Northern Madurai Block suggest four deformational events (D1–D4), some of which are likely to be contemporaneous. The timing of high pressure-ultrahigh temperature metamorphism and deformation (D1–D3) in the Madurai Block (here interpreted as the southern extension of Azania) is constrained to circa 550–500 Ma and interpreted as representing collisional orogeny and subsequent orogenic collapse of the eastern margin of the East African Orogen. The disparity in the nature of the structural fabrics and the timing of the deformation in the Salem and the Madurai Blocks suggest that the two experienced distinct tectonothermal events prior to their amalgamation along the Cauvery shear zone during the Ediacaran/Cambrian

    A three-arm feasibility randomised controlled trial comparing antipsychotic medication to psychological intervention to a combined treatment in adolescents with first episode psychosis: The Managing Adolescent first episode Psychosis Study (MAPS)

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    Background: The evidence base for treatments for early-onset psychosis (EOP) is limited and of low quality. Current guidance for the treatment of EOP is mostly extrapolated from trials in adult populations. NICE, in the United Kingdom (UK), make a specific research recommendation for the evaluation of clinical and cost-effectiveness of antipsychotics (AP), versus psychological intervention (cognitive behaviour therapy [CBT] and family intervention), versus combination treatment for EOP. The National Institute for Health Research (NIHR) in the UK commissioned this research to establish feasibility and acceptability of a definitive trial examining these three treatment options. Methods: We conducted a multi-site, Prospective Randomised Open Blinded Evaluation (PROBE) design, feasibility randomised controlled trial (RCT) comparing AP monotherapy with psychological intervention monotherapy (PI) plus a combination of these treatments in 14-18-year olds with a first episode of psychosis. We recruited participants from seven United Kingdom sites. Participants were followed-up at six and 12 months. Cognitive behavioural therapy incorporated up to 26 sessions over 6 months plus up to four booster sessions. Family intervention included up to six sessions over 6 months. Choice and dose of antipsychotic were at the discretion of the treating consultant psychiatrist. The primary outcome was feasibility data (recruitment, retention, acceptability) and the main effectiveness outcome was the Positive and Negative Syndrome Scale (PANSS) total score at 6 months. We conducted a repeated-measures analysis of the proposed primary outcome (PANSS) and the secondary outcome, the Questionnaire about the Process of Recovery (QPR) using a mixed effects model to account for the discrete timing of the follow-up assessments and adjusted for site. Safety outcomes were reported on the basis of as treated status defined as any one session of CBT or any one dose of APs; descriptive statistics are reported for safety outcomes. The study was prospectively registered on 27th February 2017, http://www.isrctn.com/ISRCTN80567433. Findings: 61 patients (aged 14-18 years; mean 16.3, SD 1.3) were recruited from 1st April 2017 to 31st October 2018, 18 were assigned to psychological intervention, 22 to antipsychotics and 21 to the combination. The feasibility of recruitment was unclear, since the trial only recruited 61 of a target of 90 participants. The study had a low referral: randomisation ratio (101:61), high rates of retention (>80%), high rates of adherence for psychological intervention (82.1%) defined as 6 or more sessions of CBT, and moderate rates of adherence for antipsychotic medication (65.1%), defined as 6 or more consecutive weeks of APs. The median number of sessions for CBT for those in the PI arm was 14 (IQR 9, 23) and 15 in the combined arm (IQR 9, 17). Of those in receipt of APs the mean duration that the participant remained on the medication was 31.5 weeks (SD 14.6, minimum 8.7 and maximum 52). There were no serious adverse events considered to be related to the trial. Interpretation: This is the first trial to show that it is safe to conduct a head-to-head clinical trial comparing psychological intervention with antipsychotics and the combination in people in young people with a first-episode psychosis. However, feasibility is unclear due to not meeting the recruitment progression criteria, so amendments to trial design are required in order to conduct an adequately powered clinical and cost effectiveness trial to provide robust evidence

    Initial Delay in the Immune Response to Francisella tularensis Is Followed by Hypercytokinemia Characteristic of Severe Sepsis and Correlating with Upregulation and Release of Damage-Associated Molecular Patterns▿

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    “Francisella tularensis subsp. novicida” intranasal infection causes a rapid pneumonia in mice with mortality at 4 to 6 days with a low dose of bacteria (102 bacteria). The short time to death suggests that there is a failure of the innate immune response. As the neutrophil is often the first cell type to infiltrate sites of infection, we focused on the emigration of neutrophils in this infection, as well as cytokines involved in their recruitment. The results indicated that there was a significant delay in the influx of neutrophils into the bronchoalveolar lavage fluid of F. tularensis subsp. novicida-infected mice. The delay in neutrophil recruitment in F. tularensis subsp. novicida-infected mice correlated with a delay in the upregulation of multiple proinflammatory cytokines and chemokines, as well as a delay in caspase-1 activation. Strikingly, the initial delay in the upregulation of cytokines through 1 day postinfection was followed by profound upregulation of multiple cytokines and chemokines to levels consistent with hypercytokinemia described for severe sepsis. This finding was further supported by a bacteremia and the cellular relocalization and release of high-mobility group box-1 and S100A9, both of which are damage-associated molecular pattern molecules and are known to be mediators of severe sepsis
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