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1.
Nat Commun ; 15(1): 3424, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654023

RESUMEN

Developing unique mechanisms of action are essential to combat the growing issue of antimicrobial resistance. Supramolecular assemblies combining the improved biostability of non-natural compounds with the complex membrane-attacking mechanisms of natural peptides are promising alternatives to conventional antibiotics. However, for such compounds the direct visual insight on antibacterial action is still lacking. Here we employ a design strategy focusing on an inducible assembly mechanism and utilized electron microscopy (EM) to follow the formation of supramolecular structures of lysine-rich heterochiral ß3-peptides, termed lamellin-2K and lamellin-3K, triggered by bacterial cell surface lipopolysaccharides. Combined molecular dynamics simulations, EM and bacterial assays confirmed that the phosphate-induced conformational change on these lamellins led to the formation of striped lamellae capable of incising the cell envelope of Gram-negative bacteria thereby exerting antibacterial activity. Our findings also provide a mechanistic link for membrane-targeting agents depicting the antibiotic mechanism derived from the in-situ formation of active supramolecules.


Asunto(s)
Antibacterianos , Membrana Celular , Simulación de Dinámica Molecular , Antibacterianos/farmacología , Antibacterianos/química , Membrana Celular/efectos de los fármacos , Lipopolisacáridos/farmacología , Pruebas de Sensibilidad Microbiana , Péptidos/química , Péptidos/farmacología , Microscopía Electrónica , Bacterias Gramnegativas/efectos de los fármacos , Escherichia coli/efectos de los fármacos
2.
Expert Rev Vaccines ; 23(1): 303-311, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38426479

RESUMEN

BACKGROUND: Respiratory syncytial virus (RSV), a common respiratory pathogen, can lead to severe symptoms, especially in older adults (OA). A recently developed RSV prefusion F protein (RSVPreF3 OA) vaccine confers high protection against RSV lower respiratory tract disease (LRTD) over two full RSV seasons. The aim of this study was to assess the potential public health impact of RSVPreF3 OA vaccination in the Japanese OA population. RESEARCH DESIGN AND METHODS: A static Markov model was used to estimate the number of symptomatic RSV cases, hospitalizations and deaths in the Japanese population aged ≥ 60 years over a 3-year time horizon. Japan-specific RSV epidemiology and healthcare resource use parameters were used; vaccine efficacy was derived from a phase 3 randomized study (AReSVi-006, NCT04886596). Vaccination coverage was set to 50%. RESULTS: Without vaccination, >5 million RSV acute respiratory illness (ARI) would occur (2.5 million LRTD and 2.8 million upper respiratory tract infections) leading to ~ 3.5 million outpatient visits, >534,000 hospitalizations and ~ 25,500 RSV-related deaths over 3 years. Vaccination could prevent > 1 million RSV-ARI cases, 728,000 outpatient visits, 143,000 hospitalizations and 6,840 RSV-related deaths. CONCLUSIONS: RSVPreF3 OA vaccination is projected to have a substantial public health impact by reducing RSV-related morbidity and mortality in the OA population.


Respiratory syncytial virus (RSV) is one of the most frequent disease-causing agents that leads to common cold symptoms. In older adults, infection with RSV can result in severe complications including bronchitis/bronchiolitis, lung infection (pneumonia) and in rare cases death. Older people and people with chronic heart or lung disease are more likely to experience complications. We estimated that more than 5 million RSV cases occur in older adults (≥60 years) over a three-year period (1.8 million over one year). Many older adults (≥60 years) will see their treating physician because of an acute RSV infection or will be hospitalized.Recently, a vaccine has been registered which protects older adults against RSV disease: the RSV prefusion F protein Older Adult (RSVPreF3 OA) vaccine. Vaccination with RSVPreF3 OA could prevent RSV infection in the older adult population and reduce the number of outpatient visits and hospitalizations; the impact is particularly high in Japan, where 35% of people are 60 years or older. We used a public health impact model to estimate how many RSV cases, hospitalizations and deaths could be prevented if 50% of people aged ≥ 60 years received the RSVPreF3 OA vaccine: We found that the vaccine could prevent about 1 million RSV infections, more than 728,000 outpatient visits, approximately 143,000 hospitalizations and 6,840 RSV-related deaths over a three-year period.Adding RSVPreF3 OA vaccine to the national immunization program in Japan could protect older adults against RSV disease and reduce the burden on patients and the healthcare system.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Humanos , Anciano , Japón/epidemiología , Salud Pública , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Anticuerpos Antivirales
3.
Infect Dis Ther ; 13(4): 827-844, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38507143

RESUMEN

INTRODUCTION: Respiratory syncytial virus (RSV) is an important cause of lower respiratory tract disease in older adults, resulting in substantial morbidity and mortality. METHODS: This study estimates the public health impact of vaccination with the adjuvanted RSVPreF3 vaccine among adults aged ≥ 60 years in the United States (US). A static, multi-cohort Markov model was used to estimate RSV-related outcomes over a 3-year time horizon for scenarios with and without one-time RSV vaccination. The base-case analysis assumed the same vaccination coverage as for influenza vaccines, with key epidemiology and vaccine inputs obtained from the published literature and phase 3 clinical trial results for the adjuvanted RSVPreF3 vaccine. Model outcomes included the clinical burden of RSV (symptomatic RSV acute respiratory illness [RSV-ARI] cases [classified as upper or lower respiratory tract disease], pneumonia complications, and mortality) and RSV-related healthcare resource use (hospitalizations, emergency department visits, outpatient visits, and antibiotic prescriptions). RESULTS: In the base-case analysis, approximately 56.7 million adults aged ≥ 60 years received the vaccine, resulting in 2,954,465 fewer symptomatic RSV-ARI cases over 3 years compared with no vaccination, including 321,019 fewer X-ray confirmed pneumonia cases and 16,660 fewer RSV-related deaths. Vaccination also prevented a substantial number of RSV-related hospitalizations (203,891), emergency department visits (164,060), outpatient visits (1,577,586), and antibiotic prescriptions (1,343,915) over the 3-year period. A considerable public health impact was observed across a range of sensitivity analyses. CONCLUSIONS: These findings highlight the potential of the adjuvanted RSVPreF3 vaccine to substantially reduce RSV disease burden among US older adults aged ≥ 60 years.

4.
Influenza Other Respir Viruses ; 18(2): e13236, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38314063

RESUMEN

Background: Respiratory syncytial virus (RSV) is a contagious pathogen causing acute respiratory infections (ARIs). Symptoms range from mild upper respiratory tract infections to potentially life-threatening lower respiratory tract disease (LRTD). In adults ≥60 years old, vaccine efficacy of a candidate vaccine for older adults (RSVPreF3 OA) was 71.7% against RSV-ARI and 82.6% against RSV-LRTD (AReSVi-006/NCT04886596). We present the patient-reported outcomes (PROs) from the same trial at the end of the first RSV season in the northern hemisphere (April 2022). Methods: In this phase 3 trial, adults aged ≥60 years were randomized (1:1) to receive one dose of RSVPreF3 OA vaccine or placebo. PROs were assessed using InFLUenza Patient-Reported Outcome (FLU-PRO), Short Form-12 (SF-12), and EuroQol-5 Dimension (EQ-5D) questionnaires. Peak FLU-PRO Chest/Respiratory scores during the first 7 days from ARI episode onset were compared using a Wilcoxon test. Least squares mean (LSMean) of SF-12 physical functioning (PF) and EQ-5D health utility scores were estimated using mixed effects models. Results: In the RSVPreF3 OA group (N = 12,466), 27 first RSV-ARI episodes were observed versus 95 in the Placebo group (N = 12,494). Median peak FLU-PRO Chest/Respiratory scores were lower in RSVPreF3 OA (1.07) versus Placebo group (1.86); p = 0.0258. LSMean group differences for the PF and EQ-5D health utility score were 7.00 (95% confidence interval [CI]: -9.86, 23.85; p = 0.4125) and 0.0786 (95% CI: -0.0340, 0.1913; p = 0.1695). Conclusions: The RSVPreF3 OA vaccine, in addition to preventing infection, attenuated the severity of RSV-associated symptoms in breakthrough infections, with trends of reduced impact on PF and health utility.


Asunto(s)
Gripe Humana , Infecciones por Virus Sincitial Respiratorio , Vacunas contra Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Humanos , Anciano , Persona de Mediana Edad , Vacunas contra Virus Sincitial Respiratorio/uso terapéutico , Infección Irruptiva , Proteínas Virales de Fusión , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Gripe Humana/prevención & control , Gripe Humana/tratamiento farmacológico , Anticuerpos Antivirales , Anticuerpos Neutralizantes
5.
J Mark Access Health Policy ; 11(1): 2239557, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37583879

RESUMEN

Background: The benefits of preventive interventions lack comprehensive evaluation in standard health technology assessments (HTA), particularly for rare and transmissible diseases. Objective: To identify possible considerations for future HTA using analogies between the treatment and prevention of rare diseases. Study design: An Expert panel meeting assessed whether one HTA assessment framework can be applied to assess both rare disease treatments and preventive interventions. Experts also evaluated the range of value elements currently included in HTAs and their applicability to rare, transmissible, and/or preventable diseases. Results: A broad range of value should be considered when assessing rare, transmissible disease prevention. Although standard HTA can be applied to transmissible diseases, the risk of local outbreaks and the need for large-scale prevention programs suggest a modified assessment framework, capable of incorporating prevention-specific value elements in HTAs. A 'Rule of Prevention' framework was proposed to allow broader value considerations anchored to severity, equity, and prevention benefits in decision-making for preventive interventions for rare transmissible diseases. Conclusion: The proposed prevention framework introduces an explicit initial approach to consistently assess rare transmissible diseases, and to incorporate the broader value of preventive interventions compared with treatment.

6.
Eur J Pharm Biopharm ; 178: 117-130, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35961565

RESUMEN

During the filling process of a biopharmaceutical drug product (DP), a liquid DP film might creep up the inner vial wall which is barely discernible, appears as milky-white haze after lyophilisation and is known as fogging. Creeping and fogging are mainly dependent on the primary packaging material surface and its hydration, vial preparation process as well as DP composition. The occurrence of both can impede visual inspection and might lead to DP rejection. Hence, our studies focused on the early detection of liquid solution and glass vial surface interaction directly after filling. For a fast and highly sensitive evaluation a novel video-based analysis was used. To our knowledge, this is the first time a MATLAB®-algorithm-based video analysis was applied to quantitatively determine creeping time-resolved. Furthermore, creeping in dependence of vial processing sites, surfactant type and concentration, filling temperature, and vial format were investigated. The results were verified using orthogonal conventional methods such as surface tension, wetting behaviour, and contact angle measurements, as well as ToF-SIMS, ICP-MS, and SEM. Additionally, the methods applied were assessed regarding their cross-validation capability. The observations indicate that the vial preparation process can have a pronounced impact on alteration of the glass vial surface and related creeping behaviour of the filled solution.


Asunto(s)
Embalaje de Medicamentos , Vidrio , Algoritmos , Embalaje de Medicamentos/métodos , Liofilización , Preparaciones Farmacéuticas
7.
Hum Vaccin Immunother ; 18(5): 2058304, 2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-35486410

RESUMEN

Seasonal influenza causes many cases and related deaths in Europe annually, despite ongoing vaccination programs for older adults and people at high-risk of complications. Children have the highest risk of infection and play a key role in disease transmission. Our cost-utility analysis, based on a dynamic transmission model, estimated the impact of increasing the current vaccination coverage with inactivated quadrivalent influenza vaccine in Germany to all (healthy and high-risk) children under 5 years of age (40% uptake), or under 18 years (40% uptake), or only high-risk children under 18 years (90% uptake). Eight influenza complications were modeled, hospitalization and death rates were based on age and risk status. All three vaccination strategies provided more health benefits than the existing vaccination situation, reducing influenza cases, complications, hospitalizations and deaths across the entire population. The strategy targeting all children under 5 years was highly cost-effective (€6/quality-adjusted life-year gained, payer perspective). The other strategies were cost saving from the payer and societal perspectives. The vaccination strategy targeting all children under 18 years was estimated to provide the most health benefits (preventing on average 1.66 million cases, 179,000 complications, 14,000 hospitalizations and 3,600 deaths due to influenza annually) and the most cost savings (annually €20.5 million and €731.3 million from payer and societal perspectives, respectively). Our analysis provides policy decision-makers with evidence supporting strategies to expand childhood influenza vaccination, to directly protect children, and indirectly all other unvaccinated age groups, in order to reduce the humanistic and economic burden on healthcare systems and society.


What is the context? Every winter, millions of people in Europe become ill due to influenza (flu), and some need to be hospitalized for complications that can sometimes lead to death.While mainly older adults and people with chronic illness are at higher risk of complications from influenza, children have the highest risk of infection and of transmitting the disease.Current vaccination policies in Europe, including Germany, target older adults and high-risk populations (pregnant women, children and other age groups with chronic diseases).What is new? This analysis simulates the effects of expanding current German vaccination programs in high-risk children to include healthy children, and of increasing vaccination coverage rates, for direct protection against infection, and to reduce the disease transmission in the rest of the population.We modeled three vaccination strategies: vaccinating 40% of all (healthy and high- risk) children under 5 years old;vaccinating 40% of all (healthy and high-risk) children under 18 years old;vaccinating 90% of high-risk children under 18 years old.What is the impact? All three strategies resulted in health gains, as more influenza cases, complications and deaths were prevented in all age groups of the population compared to the current situation.The strategies targeting both healthy and high-risk children provided the greatest health benefits. In particular, a vaccination policy targeting all children under 18 years old was predicted to provide the most health benefits as well as the highest cost savings: the increased costs of vaccination were more than offset by the savings in disease management costs as a result of having fewer influenza patients.Vaccinating healthy children against influenza is expected to significantly reduce the disease burden in the total population while saving costs, due to reduced transmission of the disease.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Adolescente , Anciano , Niño , Preescolar , Análisis Costo-Beneficio , Alemania/epidemiología , Humanos , Gripe Humana/epidemiología , Estaciones del Año , Vacunación , Vacunas Combinadas
8.
Pharmaceutics ; 14(2)2022 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-35214083

RESUMEN

Inflammatory bowel disease (IBD) is a chronic inflammatory disease of the gastrointestinal tract with increasing incidence worldwide. Although a deeper understanding of the underlying mechanisms of IBD has led to new therapeutic approaches, treatment options are still limited. Severe adverse events in conventional drug therapy and poor drug targeting are the main cause of early therapy failure. Nanoparticle-based targeting approaches can selectively deliver drugs to the site of inflammation and reduce the risk of side effects by decreasing systemic availability. Here, we developed a nanoparticulate platform for the delivery of the anti-TNF-α antibody adalimumab (ADA) by covalent crosslinking to the particle surface. ADA binding to nanoparticles improved the stability of ADA against proteolytic degradation in vitro and led to a significantly better therapeutic outcome in a murine colitis model. Moreover, immobilization of ADA reduced systemic exposure, which can lead to enhanced therapeutic safety. Thus, nanoparticle protein decoration constitutes a platform through which epithelial delivery of any biological of interest to the inflamed gut and hence a local treatment can be achieved.

9.
PLoS One ; 17(2): e0263975, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35202428

RESUMEN

The concerted action of DNA replication and cell division has been extensively investigated in eukaryotes. Well demarcated checkpoints have been identified in the cell cycle, which provides the correct DNA stoichiometry and appropriate growth in the progeny. In bacteria, which grow faster and less concerted than eukaryotes, the linkages between cell elongation and DNA synthesis are unclear. dTTP, one of the canonical nucleotide-building blocks of DNA, is also used for cell wall biosynthesis in mycobacteria. We hypothesize that the interconnection between DNA and cell wall biosynthesis through dTTP may require synchronization of these processes by regulating dTTP availability. We investigated growth, morphology, cellular dNTP pool, and possible signs of stress in Mycobacterium smegmatis upon perturbation of rhamnose biosynthesis by the overexpression of RmlA. RmlA is a cell wall synthetic enzyme that uses dTTP as the precursor for cross-linking the peptidoglycan with the arabinogalactan layers by a phosphodiester bond in the mycobacterial cell wall. We found that RmlA overexpression results in changes in cell morphology, causing cell elongation and disruption of the cylindrical cell shape. We also found that the cellular dTTP pool is reduced by half in RmlA overexpressing cells and that this reduced dTTP availability does not restrict cell growth. We observed 2-6-fold increases in the gene expression of replication and cell wall biosynthesis stress factors upon RmlA overexpression. Using super-resolution microscopy, we found that RmlA, acting to crosslink the nascent layers of the cell wall, localizes throughout the whole cell length in a helical pattern in addition to the cellular pole.


Asunto(s)
Proteínas Bacterianas/metabolismo , Mycobacterium smegmatis/metabolismo , Nucleotidiltransferasas/metabolismo , Nucleótidos de Timina/metabolismo , Pared Celular/metabolismo , Replicación del ADN , ADN Bacteriano , Mycobacterium smegmatis/citología , Mycobacterium smegmatis/enzimología , Mycobacterium smegmatis/genética , Ramnosa/metabolismo , Estrés Fisiológico
10.
Proteins ; 90(2): 476-484, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34546588

RESUMEN

We have performed fully atomistic molecular dynamics simulations of the intracellular domain of a model of the GABAA receptor with and without the GABA receptor associated protein (GABARAP) bound. We have also calculated the electrostatic potential due to the receptor, in the absence and presence of GABARAP. We find that GABARAP binding changes the electrostatic properties around the GABAA receptor and could lead to increased conductivity of chloride ions through the receptor. We also find that ion motions that would result in conducting currents are observed nearly twice as often when GABARAP binds. These results are consistent with data from electrophysiological experiments.


Asunto(s)
Receptores de GABA-A/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Proteínas Reguladoras de la Apoptosis , Proteínas Asociadas a Microtúbulos , Unión Proteica
11.
Nucleic Acids Res ; 50(D1): D1508-D1514, 2022 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-34643700

RESUMEN

Stimulated by the growing interest in the role of dNTP pools in physiological and malignant processes, we established dNTPpoolDB, the database that offers access to quantitative data on dNTP pools from a wide range of species, experimental and developmental conditions (https://dntppool.org/). The database includes measured absolute or relative cellular levels of the four canonical building blocks of DNA and of exotic dNTPs, as well. In addition to the measured quantity, dNTPpoolDB contains ample information on sample source, dNTP quantitation methods and experimental conditions including any treatments and genetic manipulations. Functions such as the advanced search offering multiple choices from custom-built controlled vocabularies in 15 categories in parallel, the pairwise comparison of any chosen pools, and control-treatment correlations provide users with the possibility to quickly recognize and graphically analyse changes in the dNTP pools in function of a chosen parameter. Unbalanced dNTP pools, as well as the balanced accumulation or depletion of all four dNTPs result in genomic instability. Accordingly, key roles of dNTP pool homeostasis have been demonstrated in cancer progression, development, ageing and viral infections among others. dNTPpoolDB is designated to promote research in these fields and fills a longstanding gap in genome metabolism research.


Asunto(s)
Bases de Datos Genéticas , Desoxirribonucleótidos/clasificación , Inestabilidad Genómica/genética , Neoplasias/genética , Replicación del ADN/genética , Curaduría de Datos , Desoxirribonucleótidos/genética , Humanos , Neoplasias/clasificación , Neoplasias/patología
12.
ACS Appl Mater Interfaces ; 13(6): 7453-7460, 2021 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-33533590

RESUMEN

In this study, the possibilities of noise tailoring in filamentary resistive switching memory devices are investigated. To this end, the resistance and frequency scaling of the low-frequency 1/f-type noise properties are studied in representative mainstream material systems. It is shown that the overall noise floor is tailorable by the proper material choice, as demonstrated by the order-of-magnitude smaller noise levels in Ta2O5 and Nb2O5 transition-metal oxide memristors compared to Ag-based devices. Furthermore, the variation of the resistance states allows orders-of-magnitude tuning of the relative noise level in all of these material systems. This behavior is analyzed in the framework of a point-contact noise model highlighting the possibility for the disorder-induced suppression of the noise contribution arising from remote fluctuators. These findings promote the design of multipurpose resistive switching units, which can simultaneously serve as analog-tunable memory elements and tunable noise sources in probabilistic computing machines.

13.
Proc Math Phys Eng Sci ; 477(2246): 20200795, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35153544

RESUMEN

This paper investigates coupling between electromagnetic surface waves on parallel wires. Finite-element method (FEM)-based and analytic models are developed for single- and double-wire Sommerfeld and Goubau lines. Models are validated via measurements for Goubau lines and a comparison between the analytic and the FEM-based computations for coupled Sommerfeld- and Goubau-type lines is carried out. The measurements and calculations show remarkable agreement. The FEM-based and analytic models match remarkably well too. The results exhibit new favourable effects for surface waves propagation over multiple conductors. The short-range behaviour of the coupled wires and, consequently, the existence of an optimum separation of coupled wires is one of the most significant findings of this paper. We comment on the relevance of our results, particularly in relation to applications of high bandwidth demands and cross-coupling effects.

14.
Sci Rep ; 10(1): 20754, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33247168

RESUMEN

Planar Goubau lines show promise as high frequency, low-loss waveguides on a substrate. However, to date only numerical simulations and experimental measurements have been performed. This paper analytically investigates the surface wave mode propagating along a planar Goubau line consisting of a perfectly conducting circular wire on top of a dielectric substrate of finite thickness but infinite width. An approximate equation for the propagation constant is derived and solved through numerical integration. The dependence of the propagation constant on various system parameters is calculated and the results agree well with full numerical simulations. In addition, the spatial distribution of the longitudinal electric field is reported and excellent agreement with a numerical simulation and previous studies is found. Moreover, validation against experimental phase velocity measurements is also reported. Finally, insights gained from the model are considered for a Goubau line with a rectangular conductor. The analytic model reveals that the propagating mode of a planar Goubau line is hybrid in contrast to the transverse magnetic mode of a classic Goubau line.

15.
Beilstein J Nanotechnol ; 11: 92-100, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31976200

RESUMEN

Nanometer-scale resistive switching devices operated in the metallic conductance regime offer ultimately scalable and widely reconfigurable hardware elements for novel in-memory and neuromorphic computing architectures. Moreover, they exhibit high operation speed at low power arising from the ease of the electric-field-driven redistribution of only a small amount of highly mobile ionic species upon resistive switching. We investigate the memristive behavior of a so-far less explored representative of this class, the Ag/AgI material system in a point contact arrangement established by the conducting PtIr tip of a scanning probe microscope. We demonstrate stable resistive switching duty cycles and investigate the dynamical aspects of non-volatile operation in detail. The high-speed switching capabilities are explored by a custom-designed microwave setup that enables time-resolved studies of subsequent set and reset transitions upon biasing the Ag/AgI/PtIr nanojunctions with sub-nanosecond voltage pulses. Our results demonstrate the potential of Ag-based filamentary memristive nanodevices to serve as the hardware elements in high-speed neuromorphic circuits.

16.
Hum Vaccin Immunother ; 16(4): 836-845, 2020 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-31647348

RESUMEN

Children have a high burden of influenza and play a central role in spreading influenza. Routinely vaccinating children against influenza may, thus, not only reduce their disease burden, but also that of the general population, including the elderly who frequently suffer severe complications. Using the published individual-based tool 4Flu, we simulated how pediatric vaccination would change infection incidence in Germany. Transmission of four influenza strains was simulated in 100,000 individuals with German demography and contact structure. After initialization with the recorded trivalent influenza vaccination coverage for 20 years (1997-2016), all vaccinations were switched to quadrivalent influenza vaccine (QIV). Scenarios where vaccination coverage of children (0.5-17-year-old) was increased from the current value (4.3%) to a maximum of 10-60% were compared to baseline with unchanged coverage, averaging results of 1,000 pairs of simulations over a 20-year evaluation period (2017-2036). Pediatric vaccination coverage of 10-60% annually prevented 218-1,732 (6.3-50.5%) infections in children, 204-1,961 (2.9-28.2%) in young adults and 95-868 (3.1-28.9%) in the elderly in a population of 100,000 inhabitants; overall, 34.1% of infections in the total population (3.7 million infections per year in Germany) can be prevented if 60% of all children are vaccinated annually. 4.4-4.6 vaccinations were needed to prevent one infection among children; 1.7-1.8 were needed to prevent one in the population. Enhanced pediatric vaccination prevents many infections in children and even more in young adults and the elderly.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Adolescente , Anciano , Niño , Preescolar , Alemania/epidemiología , Humanos , Lactante , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Vacunación , Cobertura de Vacunación , Adulto Joven
17.
Chemistry ; 25(9): 2179-2183, 2019 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-30466176

RESUMEN

The reductive Ireland-Claisen rearrangement through borane-mediated hydrosilylation is reported. The method employs a borane catalyst with a special structural design and affords access to synthetically relevant products with high diastereoselectivity. Depending on electronic and structural parameters, the reaction can be coupled with a 1,3-allylic shift, thus the valence isomer of the Ireland-Claisen product is formed.

18.
Nanoscale ; 10(41): 19290-19296, 2018 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-30325385

RESUMEN

The dynamical aspects of bipolar resistive switchings have been investigated in Nb/Nb2O5/PtIr nanojunctions. We found that the widely tuneable ON and OFF state resistances are well separated at low bias. On the other hand, the high-bias regime of the resistive switchings coincides with the onset of a high nonlinearity in the current-voltage characteristics, where the impedance of both states rapidly decreases and becomes equivalent around 50 Ω. This phenomenon enables the overriding of the RC limitations of fast switchings between higher resistance ON and OFF states. Consequently, nanosecond switching times between multiple resistance states due to subnanosecond voltage pulses are demonstrated. Moreover, this finding provides the possibility of impedance engineering by the appropriate choice of voltage signals, which facilitates that both the set and reset transitions take place in an impedance matched manner to the surrounding circuit, demonstrating the merits of ultra-fast operation of Nb2O5 based neuromorphic networks.

19.
J Environ Manage ; 204(Pt 1): 540-550, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-28934677

RESUMEN

Stakeholder participation in nature conservation policies and especially in the management of protected areas has gained importance in the last decades. These changes are underlined by democratic principles and the perceived contribution of stakeholder involvement to the effectiveness of conservation management. Evaluating participatory processes is essential to learn about the past and thus increase the quality of future processes. The evaluation can be useful for the organisations responsible for planning and management, stakeholders and policy makers as well. The present paper shows the results of a systematic evaluation of 25 participatory processes related to the development of management plans for Natura 2000 sites in Hungary between 2007 and 2015. A conceptual framework was developed to evaluate the process and outcome of participatory management planning processes. Criteria were based on the scientific literature on public participation and tailored to conservation-related management planning and stakeholder involvement. Evaluated processes were grouped in three cases based on their time range and financial sources. Overall, the analysed processes scored at a medium level, showing better performance in the process criteria than in the outcome criteria. The best case scored significantly higher in four criteria compared to the other cases: representativeness, resource availability for facilitation, new, creative ideas and impact on the plan. The main factors behind the success were (1) embeddedness of the planning process in a larger project, where the plan was a tool for conservation, (2) carrying out only one process at a time, (3) previous experience of facilitators and planners with participatory planning and (4) the opportunity and capacity to propose a payment scheme as an incentive. But even this case received low scores in some criteria: conflict resolution, early involvement and well defined goals. Based on the results we suggest that more data is needed to evaluate the implementation of the plans and, in many cases, the impact of the process on the plan. Performance can be improved with the assistance of policy makers by further developing guidelines, harmonising payment schemes with the conservation measures of the plans and providing training on conflict resolution. The evaluation framework proved to be suitable for the assessment of a large set of conservation related management planning processes, but it also had some limitations, e.g. concerning the incorporation of stakeholders' views in the evaluation.


Asunto(s)
Participación de la Comunidad , Negociación , Conservación de los Recursos Naturales , Humanos , Hungría
20.
Eur J Pharm Biopharm ; 103: 51-61, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27016212

RESUMEN

Liposomes consist of a hydrophilic core surrounded by a phospholipid (PL) bilayer. In human blood, the half-life of such artificial vesicles is limited. To prolong their stability in the circulation, liposomal bilayers can be modified by inserting poly(ethylene glycol) (PEG) molecules using either PL or sterols as membrane anchors. This establishes a hydrophilic steric barrier, reducing the adsorption of serum proteins, recognition and elimination by cells of the immune system. In addition, targeting ligands (such as antibodies) are frequently coupled to the distal end of the PEG chains to direct the vesicles (then called 'immuno-liposomes') to specific cell types, such as tumor cells. To our knowledge, experiments on the stability of ligand anchoring have so far only been conducted with PL-based PEGs and not with sterol-based PEGs after insertion via the sterol-based post-insertion technique (SPIT). Therefore, our study examines the insertion stability of PEG-cholesteryl ester (Chol-PEG) molecules with PEG chains of 1000, 1500 and 2000Da molecular mass which have been inserted into the membranes of liposomes using SPIT. For this study we used different acceptor media and multiple analytical techniques, including pulsed-field-gradient nuclear magnetic resonance (PFG-NMR), free-flow electrophoresis, size exclusion chromatography and ultracentrifugation. The obtained data consistently showed that a higher molar mass of PEG chains positively correlates with higher release from the liposome membranes. Furthermore, we could detect and quantify the migration of Chol-PEG molecules from radioactively double-labeled surface-modified liposomes to negatively charged acceptor liposomes via free-flow electrophoresis. Insertion of Chol-PEG molecules into the membrane of preformed liposomes using SPIT is an essential step for the functionalization of liposomes with the aim of specific targeting. For the first time, we present a kinetic analysis of this insertion process using PFG-NMR, showing that insertion into the liposomal membranes takes place within 90s for Chol-PEG1000 molecules.


Asunto(s)
Colesterol/química , Liposomas , Membranas Artificiales , Polietilenglicoles/química , Cromatografía en Gel , Espectroscopía de Resonancia Magnética , Ultracentrifugación
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