39 research outputs found

    Effective Reduced Diffusion-Models: A Data Driven Approach to the Analysis of Neuronal Dynamics

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    We introduce in this paper a new method for reducing neurodynamical data to an effective diffusion equation, either experimentally or using simulations of biophysically detailed models. The dimensionality of the data is first reduced to the first principal component, and then fitted by the stationary solution of a mean-field-like one-dimensional Langevin equation, which describes the motion of a Brownian particle in a potential. The advantage of such description is that the stationary probability density of the dynamical variable can be easily derived. We applied this method to the analysis of cortical network dynamics during up and down states in an anesthetized animal. During deep anesthesia, intracellularly recorded up and down states transitions occurred with high regularity and could not be adequately described by a one-dimensional diffusion equation. Under lighter anesthesia, however, the distributions of the times spent in the up and down states were better fitted by such a model, suggesting a role for noise in determining the time spent in a particular state

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

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    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

    Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

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    Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

    Preclinical and Clinical Development of a YFV 17 D-Based Chimeric Vaccine against West Nile Virus

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    Substantial success has been achieved in the development and implementation of West Nile (WN) vaccines for horses; however, no human WN vaccines are approved. This review focuses on the construction, pre-clinical and clinical characterization of ChimeriVax-WN02 for humans, a live chimeric vaccine composed of a yellow fever (YF) 17D virus in which the prM-E envelope protein genes are replaced with the corresponding genes of the WN NY99 virus. Pre-clinical studies demonstrated that ChimeriVax-WN02 was significantly less neurovirulent than YF 17D in mice and rhesus and cynomolgus monkeys. The vaccine elicited neutralizing antibody titers after inoculation in hamsters and monkeys and protected immunized animals from lethal challenge including intracerebral inoculation of high dose of WN NY99 virus. Safety, viremia and immunogenicity of ChimeriVax-WN02 were assessed in one phase I study and in two phase II clinical trials. No safety signals were detected in the three clinical trials with no remarkable differences in incidence of adverse events (AEs) between vaccine and placebo recipients. Viremia was transient and the mean viremia levels were low. The vaccine elicited strong and durable neutralizing antibody and cytotoxic T cell responses. WN epidemiology impedes a classical licensure pathway; therefore, innovative licensure strategies should be explored

    Long-Term Persistence of Mumps Antibody after Receipt of 2 Measles-Mumps-Rubella (MMR) Vaccinations and Antibody Response after a Third MMR Vaccination among a University Population

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    Background. High attack rates among vaccinated young adults reported during the 2006 mumps outbreak in the United States heightened concerns regarding mumps vaccine failure. Methods. Serum specimens from university students and staff were tested for mumps immunoglobulin (Ig) G by enzyme immunoassay (EIA). A subset of participants vaccinated for ≤5 years and ≥15 years were tested by neutralizing antibody (NA) assay. Persons seronegative by EIA were offered a third dose of measles-mumps-rubella vaccine (MMR3), and serum specimens were obtained 7–10 days and 2–3 months after its administration. Results. Overall, 94% (95% confidence interval [CI], 91%–96%) of the 440 participants were seropositive. No differences existed in seropositivity rates by sex, age, age at receipt of the second dose of MMR vaccine (MMR2), or time since receipt of MMR2 (P = .568). The geometric mean titer (GMT) of NA among persons vaccinated with MMR2 during the previous 1–5 years was 97 (95% CI, 64–148), whereas, among those vaccinated ≥15 years before blood collection, the GMT was 58 (95% CI, 44–76) (P = .065). After MMR3, 82% (14/17) and 91% (10/11) seroconverted in 7–10 days and 2–3 months, respectively. Conclusions. Lower levels of NA observed among persons who received MMR2 ≥15 years ago demonstrates antibody decay over time. MMR3 vaccination of most seronegative persons marked the capacity to mount an anamnestic response

    Vaccination coverage among children aged 13 to 59 months in Buenos Aires, Argentina, 2002 La cobertura de la vacunación en niños de 13 a 59 meses de edad en Buenos Aires, Argentina, en 2002

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    OBJECTIVES: To estimate antigen-specific and series-complete vaccination coverage among children aged 13 to 59 months in Buenos Aires; to compare the results of a community-based household survey with coverage rates obtained from administrative records; and to identify risk factors for incomplete vaccination. METHODS: Census tracts in Buenos Aires were surveyed systematically in March and April, 2002. Three children aged 13 to 24 months and 25 to 59 months were surveyed per block in each census tract. Written documentation of vaccination was required. Risk factors associated with incomplete vaccination were identified with univariate analysis and multivariate logistic regression. RESULTS: A total of 1391 children were surveyed. Antigen-specific coverage ranged from 69.4% (95% CI 66.7%-72%) for Haemophilus influenzae type b vaccination to 99% (95% CI 98.4%-99.6%) for BCG vaccination. Except for measles, coverage estimates found in the survey did not differ substantially from those obtained from city health authority records. Multivariate logistic regression analysis showed child's age (P <0.001) and vaccination provider (public or private) (P= 0.001) to be risk factors associated with incomplete vaccination. Not being the first child (P <0.001) was associated with incomplete coverage under the long-standing program. Living in the Northern zone of the city (P= 0.001), being uninsured (P= 0.02), and lower educational level of the primary caregiver (P= 0.04) were risk factors associated with incomplete coverage under the current vaccination program. CONCLUSIONS: Although coverage rates for some vaccines were high, complete vaccination coverage remains low among children aged 13 to 59 months in Buenos Aires. Increasing coverage will require better access to vaccination, particularly in sections of the community with risk factors.<br>OBJETIVOS: Calcular la cobertura con el régimen de vacunación completo y con vacunas contra antígenos particulares en niños de 13 a 59 meses de edad en Buenos Aires; comparar los resultados de una encuesta comunitaria a domicilio con los porcentajes de cobertura indicados en los registros públicos; e identificar los factores que ponen a los niños en riesgo de no recibir todas las dosis de vacunas recomendadas bajo el régimen oficial. MÉTODOS: Se encuestaron sistemáticamente los corredores censales en Buenos Aires en marzo y abril de 2002. En cada cuadra de cada corredor censal se encuestó a tres niños entre las edades de 13 a 24 meses y de 25 a 29 meses. Se solicitaba ver una constancia de vacunación escrita. Se identificaron factores de riesgo asociados con la falta de vacunación completa mediante un análisis unifactorial y regresión logística multifactorial. RESULTADOS: Se encuestó a un total de 1 391 niños. La cobertura con vacunas contra antígenos particulares varió de 69,4% (IC95%: 66,7%-72%) en el caso de la vacuna contra Haemophilus influenzae tipo B a 99% (IC95%: 98,4%-99,6%) en el caso de la vacuna BCG. Exceptuando la vacuna contra el sarampión, las coberturas estimadas mediante la encuesta prácticamente no difirieron de las obtenidas de los registros sanitarios públicos. El análisis de regresión logística multifactorial reveló que la edad del niño (P < 0,001) y el proveedor de la vacuna (público o privado) (P = 0,001) eran factores de riesgo asociados con la vacunación incompleta. No ser el primer hijo (P < 0,001) se asoció con un régimen de vacunas incompleto en el contexto del programa de vacunación habitual. Ser residente de la zona norte de la ciudad (P = 0,001), no tener seguro (P = 0,02) y la baja escolaridad del principal guardián del niño (P = 0,04) fueron factores de riesgo asociados con la administración incompleta del régimen de vacunación bajo el programa de vacunación vigente. CONCLUSIÓN: A pesar de que los porcentajes de cobertura con algunas vacunas son altos, sigue siendo baja la frecuencia de la vacunación con el régimen completo en niños de 13 a 59 meses de edad en Buenos Aires. Para poder mejorar esta cobertura tendrá que haber mayor acceso a las vacunas, especialmente en los sectores de la comunidad que están expuestos a los factores de riesgo
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