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Background: The heart rate variability (HRV)-derived Analgesia Nociception Index (ANI™) is a continuous noninvasive tool to assess the nociception/antinociception balance in unconscious patients. It has been shown to be superior to haemodynamic variables in detecting insufficient antinociception in children, while little is known about its predictive value.Methods: The primary objective of this prospective observational pilot study in paediatric surgical patients under sevoflurane anaesthesia was to compare the predictive value of the ANI and heart rate to help decide to give additional opioids. The paediatric anaesthesiologist in charge was blinded to ANI values.Results: In patients with an ANI value <50 (indicating insufficient antinociception) at the moment of decision, ANI values dropped from ±55 (indicating sufficient antinociception) to ±35, starting 60 s before decision. Within 120 s after administration of fentanyl (1 μg/kg), ANI values returned to ±60. This phenomenon was only observed in the ANI values derived from HRV data averaged over 2 min. Heart rate remained unchanged. In patients with ANI values ≥50 at the time of decision, opioid administration had no effect on ANI or heart rate. The same accounts for morphine for postoperative analgesia and fentanyl in case of intraoperative movement.Conclusions: This study provides evidence of a better predictive value of the ANI in detecting insufficient antinociception in paediatric surgical patients than heart rate. The same accounts for depicting re-establishment of sufficient antinociception after opioid drug administration.Significance: In paediatric surgical patients anaesthetized with sevoflurane, the heart rate variability-derived Analgesia Nociception Index (ANI) appears to be a better predictor of insufficient antinociception than heart rate. The ANI also appears to depict re-establishment of sufficient antinociception better than heart rate. [ABSTRACT FROM AUTHOR]

We identified a new human leukocyte antigen-A allele, designated HLA-A*24:215, by sequencing-based typing of a stem cell transplant patient. [ABSTRACT FROM AUTHOR]

Introduction: Dysarthria is highly prevalent in patients with Parkinson's disease (PD) and speech changes have already been detected in patients with prodromal PD on the acoustic level. However, the present study directly tracks underlying articulatory movements with electromagnetic articulography to investigate early speech alterations on the kinematic level in isolated REM sleep behavior disorder (iRBD) and compares them to PD and control speakers., Methods: Kinematic data of 23 control speakers, 22 speakers with iRBD, and 23 speakers with PD were collected. Amplitude, duration, and average speed of lower lip, tongue tip, and tongue body movements were analyzed. Naive listeners rated the intelligibility of all speakers., Results: Patients with iRBD produced tongue tip and tongue body movements that were larger in amplitude and longer in duration compared to control speakers, while remaining intelligible. Compared to patients with iRBD, patients with PD had smaller, longer and slower tongue tip and lower lip movements, accompanied by lower intelligibility. Thus, the data indicate that the lingual system is already affected in prodromal PD. Furthermore, lower lip and especially tongue tip movements slow down and speech intelligibility decreases if motor impairment is more pronounced., Conclusion: Patients with iRBD adjust articulatory patterns to counteract incipient motor detriment on speech to maintain their intelligibility level., Competing Interests: Declaration of competing interest The authors declare no financial or non-financial competing interests relevant to this work., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Streptococcus pneumoniae is an important human pathogen, being one of the most common causes of community-acquired pneumonia and otitis media. Antibiotic resistance in S. pneumoniae is an emerging problem, as it depletes our arsenal of effective drugs. In addition, persistence also contributes to the antibiotic crisis in many other pathogens, yet for S. pneumoniae, little is known about antibiotic-tolerant persisters and robust experimental means are lacking. Persister cells are phenotypic variants that exist as a subpopulation within a clonal culture. Being tolerant to lethal antibiotics, they underly the chronic nature of a variety of infections and even help in acquiring genetic resistance. In this study, we set out to identify and characterize persistence in S. pneumoniae. Specifically, we followed different strategies to overcome the self-limiting nature of S. pneumoniae as a confounding factor in the prolonged monitoring of antibiotic survival needed to study persistence. Under optimized conditions, we identified genuine persisters in various growth phases and for four relevant antibiotics through biphasic survival dynamics and heritability assays. Finally, we detected a high variety in antibiotic survival levels across a diverse collection of S. pneumoniae clinical isolates, which assumes that a high natural diversity in persistence is widely present in S. pneumoniae. Collectively, this proof of concept significantly progresses the understanding of the importance of antibiotic persistence in S. pneumoniae infections, which will set the stage for characterizing its relevance to clinical outcomes and advocates for increased attention to the phenotype in both fundamental and clinical research. IMPORTANCE S. pneumoniae is considered a serious threat by the Centers for Disease Control and Prevention because of rising antibiotic resistance. In addition to resistance, bacteria can also survive lethal antibiotic treatment by developing antibiotic tolerance, more specifically, antibiotic tolerance through persistence. This phenotypic variation seems omnipresent among bacterial life, is linked to therapy failure, and acts as a catalyst for resistance development. This study gives the first proof of the presence of persister cells in S. pneumoniae and shows a high variety in persistence levels among diverse strains, suggesting that persistence is a general trait in S. pneumoniae cultures. Our work advocates for higher interest for persistence in S. pneumoniae as a contributing factor for therapy failure and resistance development.

When everyday life becomes ever more permeated by digital technologies, many older people join ICT trainings to improve their digital skills. Given that digital skills include more than the command of technology (for instance, changing social practices) teaching ICT to people who grew up long before internet and social media can be challenging. The purpose of this article is to propose a theoretical account of a key element for how teaching digital skills to older people can be made successful. Drawing on qualitative interview data with 26 ICT instructors as well as concepts from sociological theory (lifeworld, role-taking) and cognitive science (dual process model), we argue that ICT training needs to take into account the lifeworlds of older participants. In order to be successful, ICT trainings have to appeal to the current lifeworlds of older people while at the same time overcome mismatching lifeworlds. By connecting content and pedagogics to the older adults' needs, values, and desires, instructors can successfully help integrate new skills into the lifeworld of the older participants., (Copyright © 2022. Published by Elsevier B.V.)

Neuroblastoma is a paediatric malignancy of the developing sympathetic nervous system. About half of the patients have metastatic disease at the time of diagnosis and a survival rate of less than 50%. Our understanding of the cellular processes promoting neuroblastoma metastases will be facilitated by the development of appropriate experimental models. In this study, we aimed to explore the invasion of neuroblastoma cells and organoids from patient-derived xenografts (PDXs) grown embedded in 3D extracellular matrix (ECM) hydrogels by time-lapse microscopy and quantitative image analysis. We found that the ECM composition influenced the growth, viability and local invasion of organoids. The ECM compositions induced distinct cell behaviours, with Matrigel being the preferred substratum for local organoid invasion. Organoid invasion was cell line- and PDX-dependent. We identified six distinct phenotypes in PDX-derived organoids. In contrast, NB cell lines were more phenotypically restricted in their invasion strategies, as organoids isolated from cell line-derived xenografts displayed a broader range of phenotypes compared to clonal cell line clusters. The addition of FBS and bFGF induced more aggressive cell behaviour and a broader range of phenotypes. In contrast, the repression of the prognostic neuroblastoma marker, MYCN , resulted in less aggressive cell behaviour. The combination of PDX organoids, real-time imaging and the novel 3D culture assays developed herein will enable rapid progress in elucidating the molecular mechanisms that control neuroblastoma invasion.

Pneumonia, of which Streptococcus pneumoniae is the most common causative agent, is considered one of the three top leading causes of death worldwide. As seen in other bacterial species, antimicrobial resistance is on the rise for this pathogen. Therefore, there is a pressing need for novel antimicrobial strategies to combat these infections. Recently, uridine diphosphate glucose pyrophosphorylase (UDPG:PP) has been put forward as a potential drug target worth investigating. Moreover, earlier research demonstrated that streptococci lacking a functional galU gene (encoding for UDPG:PP) were characterized by significantly reduced in vitro and in vivo virulence. Therefore, in this study we evaluated the anti-virulence activity of potential UDPG:PP inhibitors. They were selected in silico using a tailor-made streptococcal homology model, based on earlier listerial research. While the compounds didn't affect bacterial growth, nor affected in vitro adhesion to and phagocytosis in macrophages, the amount of polysaccharide capsule was significantly reduced after co-incubation with these inhibitors. Moreover, co-incubation proved to have a positive effect on survival in an in vivo Galleria mellonella larval infection model. Therefore, rather than targeting bacterial survival directly, these compounds proved to have an effect on streptococcal virulence by lowering the amount of polysaccharide and thereby probably boosting recognition of this pathogen by the innate immune system. While the compounds need adaptation to broaden their activity to more streptococcal strains rather than being strain-specific, this study consolidates UDPG:PP as a potential novel drug target., (Copyright © 2020 Cools, Triki, Geerts, Delputte, Fourches and Cos.)

Emerging evidence suggested a converging mechanism in neurodegenerative brain diseases (NBD) involving early neuronal network dysfunctions and alterations in the homeostasis of neuronal firing as culprits of neurodegeneration. In this study, we used paired-end short-read and direct long-read whole genome sequencing to investigate an unresolved autosomal dominant dementia family significantly linked to 7q36. We identified and validated a chromosomal inversion of ca. 4 Mb, segregating on the disease haplotype and disrupting the coding sequence of dipeptidyl-peptidase 6 gene (DPP6). DPP6 resequencing identified significantly more rare variants-nonsense, frameshift, and missense-in early-onset Alzheimer's disease (EOAD, p value = 0.03, OR = 2.21 95% CI 1.05-4.82) and frontotemporal dementia (FTD, p = 0.006, OR = 2.59, 95% CI 1.28-5.49) patient cohorts. DPP6 is a type II transmembrane protein with a highly structured extracellular domain and is mainly expressed in brain, where it binds to the potassium channel K v 4.2 enhancing its expression, regulating its gating properties and controlling the dendritic excitability of hippocampal neurons. Using in vitro modeling, we showed that the missense variants found in patients destabilize DPP6 and reduce its membrane expression (p < 0.001 and p < 0.0001) leading to a loss of protein. Reduced DPP6 and/or K v 4.2 expression was also detected in brain tissue of missense variant carriers. Loss of DPP6 is known to cause neuronal hyperexcitability and behavioral alterations in Dpp6-KO mice. Taken together, the results of our genomic, genetic, expression and modeling analyses, provided direct evidence supporting the involvement of DPP6 loss in dementia. We propose that loss of function variants have a higher penetrance and disease impact, whereas the missense variants have a variable risk contribution to disease that can vary from high to low penetrance. Our findings of DPP6, as novel gene in dementia, strengthen the involvement of neuronal hyperexcitability and alteration in the homeostasis of neuronal firing as a disease mechanism to further investigate.

Rare variants in the phospholipase D3 gene (PLD3) were associated with increased risk for late-onset Alzheimer disease (LOAD). We identified a missense mutation in PLD3 in whole-genome sequence data of a patient with autopsy confirmed Alzheimer disease (AD) and onset age of 50 years. Subsequently, we sequenced PLD3 in a Belgian early-onset Alzheimer disease (EOAD) patient (N = 261) and control (N = 319) cohort, as well as in European EOAD patients (N = 946) and control individuals (N = 1,209) ascertained in different European countries. Overall, we identified 22 rare variants with a minor allele frequency <1%, 20 missense and two splicing mutations. Burden analysis did not provide significant evidence for an enrichment of rare PLD3 variants in EOAD patients in any of the patient/control cohorts. Also, meta-analysis of the PLD3 data, including a published dataset of a German EOAD cohort, was not significant (P = 0.43; OR = 1.53, 95% CI 0.60-3.31). Consequently, our data do not support a role for PLD3 rare variants in the genetic etiology of EOAD in European EOAD patients. Our data corroborate the negative replication data obtained in LOAD studies and therefore a genetic role of PLD3 in AD remains to be demonstrated., (© 2015 The Authors. **Human Mutation published by Wiley Periodicals, Inc.)

Meta-analysis of existing genome-wide association studies on Alzheimer's disease (AD) showed subgenome-wide association of an intronic variant in the sequestosome 1 (SQSTM1) gene with AD. We performed targeted resequencing of SQSTM1 in Flanders-Belgian AD patients selected to be enriched for a genetic background (n = 435) and geographically matched nonaffected individuals (n = 872) to investigate the role of both common and rare SQSTM1 variants. Results were extended to the European early-onset dementia cohorts (926 early-onset Alzheimer's disease [EOAD] patients and 1476 nonaffected individuals). Of the 61 detected exonic variants in SQSTM1, the majority were rare (n = 57). Rare variant (minor allele frequency <0.01) burden analysis did not reveal an increased frequency of rare variants in EOAD patients in any of the separate study populations nor when meta-analyzing all cohorts. Common variants p.D292= and p.R312= showed nominal association with AD (odds ratiop.D292= = 1.11 [95% confidence interval = 1-1.22], p = 0.04), only when including the Flanders-Belgian cohort in the meta-analysis. We cannot exclude a role of SQSTM1 genetic variability in late-onset AD, but our data indicate that SQSTM1 does not play a major role in the etiology of EOAD., (Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.)

Homozygous mutations in exon 2 of TREM2, a gene involved in Nasu-Hakola disease, can cause frontotemporal dementia (FTD). Moreover, a rare TREM2 exon 2 variant (p.R47H) was reported to increase the risk of Alzheimer's disease (AD) with an odds ratio as strong as that for APOEε4. We systematically screened the TREM2 coding region within a Belgian study on neurodegenerative brain diseases (1216 AD patients, 357 FTD patients, and 1094 controls). We observed an enrichment of rare variants across TREM2 in both AD and FTD patients compared to controls, most notably in the extracellular IgV-set domain (relative risk = 3.84 [95% confidence interval = 1.29-11.44]; p = 0.009 for AD; relative risk = 6.19 [95% confidence interval = 1.86-20.61]; p = 0.0007 for FTD). None of the rare variants individually reached significant association, but the frequency of p.R47H was increased ~ 3-fold in both AD and FTD patients compared to controls, in line with previous reports. Meta-analysis including 11 previously screened AD cohorts confirmed the association of p.R47H with AD (p = 2.93×10(-17)). Our data corroborate and extend previous findings to include an increased frequency of rare heterozygous TREM2 variations in AD and FTD, and show that TREM2 variants may play a role in neurodegenerative diseases in general., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Recently, a new class of materials emerged with the assembly of DNA-coated phospholipid nanodiscs into columnar BioNanoStacks. Within these stacks, lipid discs are periodically incorporated, resulting into quasi-one-dimensional superstructures. With each disc surrounded by two recombinant scaffolding proteins, we decided to examine whether the polyhistidine tags of these proteins could be utilized to bind additional molecules or particles to these BioNanoStacks. Here we demonstrate that patterning of gold nanoparticles onto these BioNanoStacks is indeed possible. Binding occurs via a nickel-mediated interaction between the nanogolds nitrilotriacetic acid and the histidine tags of the scaffold proteins surrounding the nanodiscs. Using Monte Carlo simulations, we determine that the binding of the nanogold particles to the stacks is not a random event. By comparing the simulation and experimental results, we find that there are preferred binding sites, which affects the binding statistics.

We demonstrate the self-organization of quasi-one-dimensional nanostructures with periodic features using nature's primary three building blocks: lipids, DNA, and proteins. The periodicity of these "BioNanoStacks" is controllable through selection of the length of the DNA spacers. We show that BioNanoStacks can be reversibly assembled and disassembled through thermal melting of the DNA duplex, where the melting transition temperature is controllable not just by the DNA sequence and salt concentration, but also by the lipid composition within these superstructures. These novel materials may find applications in fields such as templated nanomaterial assembly, tissue-engineering scaffolds, or therapeutic delivery systems. Well-established techniques for chemical modification of biomolecules will also provide a broad platform for adaption and remodeling of these structures to provide optimal features for the required application.

We present a novel platform for investigating the composition-specific interactions of proteins (or other biologically relevant molecules) with model membranes composed of compositionally distinct domains. We focus on the interaction between a mitochondrial-specific lipid, cardiolipin (CL), and a peripheral membrane protein, cytochrome c (cyt c). We engineer vesicles with compositions such that they phase separate into coexisting liquid phases and the lipid of interest, CL, preferentially localizes into one of the domains (the liquid disordered (L(d)) phase). The presence of CL-rich and CL-depleted domains within the same vesicle provides a built-in control experiment to simultaneously observe the behavior of two membrane compositions under identical conditions. We find that cyt c binds strongly to CL-rich domains and observe fascinating morphological transitions within these regions of membrane. CL-rich domains start to form small buds and eventually fold up into a collapsed state. We also observe that cyt c can induce a strong attraction between the CL-rich domains of adjacent vesicles as demonstrated by the development of large osculating regions between these domains. Qualitatively similar behavior is observed when other polycationic proteins or polymers of a similar size and net charge are used instead of cyt c. We argue that these striking phenomena can be simply understood by consideration of colloidal forces between the protein and the membrane. We discuss the possible biological implications of our observations in relation to the structure and function of mitochondria.

We explore the formation of "floating" two-dimensional colloidal crystals above weakly attractive surfaces that are either positively or negatively charged. In particular, we studied crystal formation above positively charged poly-L-lysine-poly(ethylene glycol) surfaces with and without short single-stranded DNA and above negatively charged bovine albumin serum-streptavidin multilayers. Confocal microscopy revealed the evolution of crystals several micrometers above all three surfaces. Interestingly, the "flying height" of crystals was found to depend on the surface coating. All crystalline structures remained remarkably stable over weeks, even under high salt conditions. Neither lifting the crystals nor lowering them by means of buoyancy forces destroyed them.

We present a confocal microscopy study of the quasi-two-dimensional crystallization of a binary mixture of spherical colloids coated with long DNA strands. Our experiments show that in the crystalline phase the two colloidal species are completely demixed. Analysis of the lattice spacings in the two types of colloidal crystal shows that the diameters of the two species of colloids differ by 10%. We argue that the demixing in the crystalline phase is due to size segregation during crystallization. This phenomenon had been predicted in several theoretical studies. To our knowledge, the present study provides the first 'real-space' experimental confirmation of this effect.

We report an experimental study in which we compare the self-assembly of 1 mum colloids bridged through hybridization of complementary single-stranded DNA (ssDNA) strands (12 bp) attached to variable-length double-stranded DNA spacers that are grafted to the colloids. We considered three different spacer lengths: long spacers (48 500 bp), intermediate length spacers (7500 bp), and no spacers (in which case the ssDNA strands were directly grafted to the colloids). In all three cases, the same ssDNA pairs were used. However, confocal microscopy revealed that the aggregation behavior is very different. Upon cooling, the colloids coated with short and intermediate length DNAs undergo a phase transition to a dense amorphous phase that undergoes structural arrest shortly after percolation. In contrast, the colloids coated with the longest DNA systematically form finite-sized clusters. We speculate that the difference is due to the fact that very long DNA can easily be stretched by the amount needed to make only intracluster bonds, and in contrast, colloids coated with shorter DNA always contain free binding sites on the outside of a cluster. The grafting density of the DNA decreases strongly with increasing spacer length. This is reflected in a difference in the temperature dependence of the aggregates: for the two systems coated with long DNA, the resulting aggregates were stable against heating, whereas the colloids coated with ssDNA alone would dissociate upon heating.

We studied the aggregation of 1 µm colloids bridged by DNA with 32 µm contour length. We mixed two species of particles with grafted double-stranded λ-DNA displaying short, complementary single-stranded 'overhangs' as free binding-ends. Confocal microscopy showed the formation of stable, size-limited clusters in which the two species of particles were at touching contact. Simulations suggest that the observed close contact and the limitation to grow both result from entropic exclusion of the bridging DNA from the space between nearby particle surfaces.

Conditioned place preference, induced by intraperitoneal injections of 5 micrograms/kg luteinizing hormone-releasing hormone (LHRH), was studied by varying the interval between the injection of LHRH and the conditioning sessions. Place preference was investigated for five presession intervals (0, 15, 45, 75, and 120 min) in separate groups of gonadectomized male rats provided with a subcutaneous testosterone implant. It was shown that the presession interval is an important parameter in the development of LHRH-induced conditioned place preference. Place preference was not observed after conditioning with intervals of 0, 75, and 120 min. With 15 and 45 min, however, a reliable preference was induced by LHRH. This study provides insight into the onset and offset of the appetitive stimulus properties of LHRH in male rats.

Conditioned place-preference induced by intraperitoneal injections of luteinizing hormone releasing hormone (LHRH) was studied in male rats. In Experiment 1, dose-dependent effects (doses: 0, 0.2, 1 and 5 micrograms/kg) were observed in gonadectomized males provided with a subcutaneous silastic implant containing testosterone. Animals injected with 1 or 5 micrograms LHRH developed reliable preference for the LHRH-associated compartment of a two-compartment preference box. The 0 and 0.2 microgram doses were without effect. Experiment 2 further studied the place-preference effects induced by 5 micrograms LHRH, by varying the sex steroid baseline condition of the animals. A significant effect of LHRH on place-preference was found in gonadectomized males with a testosterone or estradiol implant and in gonadally intact males. Differences between these groups were not found. However, in gonadectomized males without steroid substitution, LHRH did not induce place-preference. These data indicate that rewarding properties related to LHRH treatment can be observed in male rats, provided that the males are additionally exposed to sufficient levels of circulating sex steroids.