Long-term immunity after a single yellow fever vaccination in travelers vaccinated at 60 years or older: a 10-year follow-up study

Background: In 2013, the World Health Organization (WHO) revised their position on yellow fever vaccination, in which revaccination every 10 years was no longer required, and that a single-dose provided life-long protection. However, research data on the immunogenicity of YF vaccine in people aged 60 years and over are scarce. Indeed, immunosenescence may result in lower virus neutralizing antibody titers after primary vaccination and a more rapid waning immunity. Therefore, we tested the hypothesis that older travelers, vaccinated at 60 years or older are more likely to become seronegative in comparison to young adults 10 years after primary YF vaccination.Methods: This is a 10-year follow-up study of an earlier prospective controlled cohort study. In the original trial, the neutralizing antibody response was measured in older travelers (aged 60-81 years, N=28) and young adults (aged 18-28 years, N=30) up to 28 days after a primary yellow fever vaccination. Ten years later, we collected serum samples of 22/28 (78%) elderly (71-85 years) and 14/30 (47%) controls (29-40 years), and determined their neutralizing antibody titers by plaque reduction neutralization test (PRNT80). Seropositivity was defined as plaque formation reduction of 80% at a serum dilution of 10 or more (PRNT80 >= 10).Results: All participants (36/36) were still seropositive 10 years after primary vaccination. The geometric mean concentrations were not statistically different between the older and younger participants (6.7 IU/mL vs. 8.6 IU/mL, P=0.5).Conclusions: All older travelers were seropositive, 10 years after a primary YF vaccination at the age of >= 60 years. These data suggest that in older travelers a single vaccination is sufficient to convey long-lasting immunity for at least 10 years, and is in support the position of the WHO on a single-dose yellow fever vaccination.Immunogenetics and cellular immunology of bacterial infectious disease

The relative contribution of mechanical stress and systemic processes in different types of osteoarthritis: the NEO study

Pathophysiology and treatment of rheumatic disease

Differences in insect resistance between tomato species endemic to the Galapagos Islands

Background The Galapagos Islands constitute a highly diverse ecosystem and a unique source of variation in the form of endemic species. There are two endemic tomato species, Solanum galapagense and S. cheesmaniae and two introduced tomato species, S. pimpinellifolium and S. lycopersicum. Morphologically the two endemic tomato species of the Galapagos Islands are clearly distinct, but molecular marker analysis shows no clear separation. Tomatoes on the Galapagos are affected by both native and exotic herbivores. Bemisia tabaci is one of the most important introduced insects species that feeds on a wide range of plants. In this article, we address the question whether the differentiation between S. galapagense and S. cheesmaniae may be related to differences in susceptibility towards phloem-feeders and used B. tabaci as a model to evaluate this. Results We have characterized 12 accessions of S. galapagense, 22 of S. cheesmaniae, and one of S. lycopersicum as reference for whitefly resistance using no-choice experiments. Whitefly resistance was found in S. galapagense only and was associated with the presence of relatively high levels of acyl sugars and the presence of glandular trichomes of type I and IV. Genetic fingerprinting using 3316 SNP markers did not show a clear differentiation between the two endemic species. Acyl sugar accumulation as well as the climatic and geographical conditions at the collection sites of the accessions did not follow the morphological species boundaries

Replicated analysis of the genetic architecture of quantitative traits in two wild great tit populations

Currently, there is much debate on the genetic architecture of quantitative traits in wild populations. Is trait variation influenced by many genes of small effect or by a few genes of major effect? Where is additive genetic variation located in the genome? Do the same loci cause similar phenotypic variation in different populations? Great tits (Parus major) have been studied extensively in long-term studies across Europe and consequently are considered an ecological ‘model organism’. Recently, genomic resources have been developed for the great tit, including a custom SNP chip and genetic linkage map. In this study, we used a suite of approaches to investigate the genetic architecture of eight quantitative traits in two long-term study populations of great tits—one in the Netherlands and the other in the United Kingdom. Overall, we found little evidence for the presence of genes of large effects in either population. Instead, traits appeared to be influenced by many genes of small effect, with conservative estimates of the number of contributing loci ranging from 31 to 310. Despite concordance between population-specific heritabilities, we found no evidence for the presence of loci having similar effects in both populations. While population-specific genetic architectures are possible, an undetected shared architecture cannot be rejected because of limited power to map loci of small and moderate effects. This study is one of few examples of genetic architecture analysis in replicated wild populations and highlights some of the challenges and limitations researchers will face when attempting similar molecular quantitative genetic studies in free-living populations

SAAP-148 eradicates MRSA persisters within mature biofilm models simulating prosthetic joint infection

Prosthetic joint infection (PJI) is a severe complication of arthroplasty. Due to biofilm and persister formation current treatment strategies often fail. Therefore, innovative anti-biofilm and anti-persister agents are urgently needed. Antimicrobial peptides with their broad antibacterial activities may be such candidates. An in vitro model simulating PJI comprising of rifampicin/ciprofloxacin-exposed, mature methicillin-resistant Staphylococcus aureus (MRSA) biofilms on polystyrene plates, titanium/aluminium/niobium disks, and prosthetic joint liners were developed. Bacteria obtained from and residing within these biofilms were exposed to SAAP-148, acyldepsipeptide-4, LL-37, and pexiganan. Microcalorimetry was used to monitor the heat flow by the bacteria in these models. Daily exposure of mature biofilms to rifampicin/ciprofloxacin for 3 days resulted in a 4-log reduction of MRSA. Prolonged antibiotic exposure did not further reduce bacterial counts. Microcalorimetry confirmed the low metabolic activity of these persisters. SAAP-148 and pexiganan, but not LL-37, eliminated the persisters while ADEP4 reduced the number of persisters. SAAP-148 further eradicated persisters within antibiotics-exposed, mature biofilms on the various surfaces. To conclude, antibiotic-exposed, mature MRSA biofilms on various surfaces have been developed as in vitro models for PJI. SAAP-148 is highly effective against persisters obtained from the biofilms as well as within these models. Antibiotics-exposed, mature biofilms on relevant surfaces can be instrumental in the search for novel treatment strategies to combat biofilm-associated infections.Orthopaedics, Trauma Surgery and Rehabilitatio

Combined biotic and abiotic stress resistance in tomato

Abiotic and biotic stress factors are the major constrains for the realization of crop yield potential. As climate change progresses, the spread and intensity of abiotic as well as biotic stressors is expected to increase, with increased probability of crops being exposed to both types of stress. Shielding crops from combinatorial stress requires a better understanding of the plant’s response and its genetic architecture. In this study, we evaluated resistance to salt stress, powdery mildew and to both stresses combined in tomato, using the Solanum habrochaites LYC4 introgression line (IL) population. The IL population segregated for both salt stress tolerance and powdery mildew resistance. Using SNP array marker data, QTLs were identified for salt tolerance as well as Na+ and Cl- accumulation. Salt stress increased the susceptibility of the population to powdery mildew in an additive manner. Phenotypic variation for disease resistance was reduced under combined stress as indicated by the coefficient of variation. No correlation was found between disease resistance and Na+ and Cl- accumulation under combined stress Most genetic loci were specific for either salt stress tolerance or powdery mildew resistance. These findings increase our understanding of the genetic regulation of responses to abiotic and biotic stress combinations and can provide leads to more efficiently breeding tomatoes and other crops with a high level of disease resistance while maintaining their performance in combination with abiotic stress

Effects of smoking and body mass index on the exposure of fentanyl in patients with cancer

The transdermal fentanyl patch is widely used to treat cancer-related pain despite its wide inter- and intrapatient variability in pharmacokinetics. The aim of this study was to investigate whether smoking and body size (i.e. body mass index) influence fentanyl exposure in patients with cancer. These are factors that typically change during treatment and disease trajectories. We performed an explorative cohort study in patients with cancer using transdermal fentanyl patches (Durogesic®), by taking a blood sample for pharmacokinetic analysis one day after applying a patch in patients with a stable fentanyl dose. A total of 88 patients were evaluable. Although no statisticall

To Fear is to Gain? The Role of Fear Recognition in Risky Decision Making in TBI Patients and Healthy Controls

Fear is an important emotional reaction that guides decision making in situations of ambiguity or uncertainty. Both recognition of facial expressions of fear and decision making ability can be impaired after traumatic brain injury (TBI), in particular when the frontal lobe is damaged. So far, it has not been investigated how recognition of fear influences risk behavior in healthy subjects and TBI patients. The ability to recognize fear is thought to be related to the ability to experience fear and to use it as a warning signal to guide decision making. We hypothesized that a better ability to recognize fear would be related to a better regulation of risk behavior, with healthy controls outperforming TBI patients. To investigate this, 59 healthy subjects and 49 TBI patients were assessed with a test for emotion recognition (Facial Expression of Emotion: Stimuli and Tests) and a gambling task (Iowa Gambling Task (IGT)). The results showed that, regardless of post traumatic amnesia duration or the presence of frontal lesions, patients were more impaired than healthy controls on both fear recognition and decision making. In both groups, a significant relationship was found between better fear recognition, the development of an advantageous strategy across the IGT and less risk behavior in the last blocks of the IGT. Educational level moderated this relationship in the final block of the IGT. This study has important clinical implications, indicating that impaired decision making and risk behavior after TBI can be preceded by deficits in the processing of fear

Genetic variance in fitness indicates rapid contemporary adaptive evolution in wild animals

The rate of adaptive evolution, the contribution of selection to genetic changes that increase mean fitness, is determined by the additive genetic variance in individual relative fitness. To date, there are few robust estimates of this parameter for natural populations, and it is therefore unclear whether adaptive evolution can play a meaningful role in short-term population dynamics. We developed and applied quantitative genetic methods to long-term datasets from 19 wild bird and mammal populations and found that, while estimates vary between populations, additive genetic variance in relative fitness is often substantial and, on average, twice that of previous estimates. We show that these rates of contemporary adaptive evolution can affect population dynamics and hence that natural selection has the potential to partly mitigate effects of current environmental change

Physical Processes in Star Formation

© 2020 Springer-Verlag. The final publication is available at Springer via https://doi.org/10.1007/s11214-020-00693-8.Star formation is a complex multi-scale phenomenon that is of significant importance for astrophysics in general. Stars and star formation are key pillars in observational astronomy from local star forming regions in the Milky Way up to high-redshift galaxies. From a theoretical perspective, star formation and feedback processes (radiation, winds, and supernovae) play a pivotal role in advancing our understanding of the physical processes at work, both individually and of their interactions. In this review we will give an overview of the main processes that are important for the understanding of star formation. We start with an observationally motivated view on star formation from a global perspective and outline the general paradigm of the life-cycle of molecular clouds, in which star formation is the key process to close the cycle. After that we focus on the thermal and chemical aspects in star forming regions, discuss turbulence and magnetic fields as well as gravitational forces. Finally, we review the most important stellar feedback mechanisms.Peer reviewedFinal Accepted Versio