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1.
Data Brief ; 54: 110254, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38962210

ABSTRACT

The current work presents the generation of a comprehensive spatial dataset of a lightweight beam element composed of four twisted plywood strips, achieved through the application of Structure-from-Motion (SfM) - Multi-view Stereo (MVS) photogrammetry techniques in controlled laboratory conditions. The data collection process was meticulously conducted to ensure accuracy and precision, employing scale bars of varying lengths. The captured images were then processed using photogrammetric software, leading to the creation of point clouds, meshes, and texture files. These data files represent the 3D model of the beam at different mesh sizes (raw, high-poly, medium-poly, and low-poly), adding a high level of detail to the 3D visualization. The dataset holds significant reuse potential and offers essential resources for further studies in numerical modeling, simulations of complex structures, and training machine learning algorithms. This data can also serve as validation sets for emerging photogrammetry methods and form-finding techniques, especially ones involving large deformations and geometric nonlinearities, particularly within the structural engineering field.

2.
Struct Dyn ; 11(2): 024309, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38595978

ABSTRACT

For time-resolved diffraction studies of irreversible structural dynamics upon photoexcitation, there are constraints on the number of perturbation cycles due to thermal effects and accumulated strain, which impact the degree of crystal order and spatial resolution. This problem is exasperated for surface studies that are more prone to disordering and defect formation. Ultrafast electron diffraction studies of these systems, with the conventional stroboscopic pump-probe protocol, require repetitive measurements on well-prepared diffraction samples to acquire and average signals above background in the dynamic range of interest from few tens to hundreds of picoseconds. Here, we present ultrafast streaked low-energy electron diffraction (LEED) that demands, in principle, only a single excitation per nominal data acquisition timeframe. By exploiting the space-time correlation characteristics of the streaking method and high-charge 2 keV electron bunches in the transmission geometry, we demonstrate about one order of magnitude reduction in the accumulated number of the excitation cycles and total electron dose, and 48% decrease in the root mean square error of the model fit residual compared to the conventional time-scanning measurement. We believe that our results demonstrate a viable alternative method with higher sensitivity to that of nanotip-based ultrafast LEED studies relying on a few electrons per a single excitation, to access to all classes of structural dynamics to provide an atomic level view of surface processes.

3.
Eur Arch Psychiatry Clin Neurosci ; 274(2): 343-352, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37532863

ABSTRACT

BACKGROUND: Prenatal alcohol exposure (PAE) has been linked to severe, adverse child outcomes. However, little is known regarding subclinical outcomes of low/moderate PAE and its longitudinal consequences, especially regarding neurophysiological and neurocognitive development. A newborn biomarker of PAE, meconium ethyl glucuronide (EtG), has been shown to predict cognitive impairments in primary-school-aged children. The current study investigated the ongoing effects of subclinical PAE in adolescence. METHODS: A sample of n = 96 mother-child dyads of the FRAMES/FRANCES cohort were classified into PAE/no PAE using EtG with a 10 ng/g cutoff. Mothers were recruited during pregnancy and children were assessed during primary-school age (M = 7.57, SD = 0.65, range: 6.00-9.92 years) and adolescence (M = 13.26, SD = 0.31, range: 12.79-14.20 years) on three levels: clinical (ADHD rating), neuropsychological (IQ score and performance in a go/nogo task), and neurophysiological (analysis of P3 event-related potentials (ERP) during said go/nogo task). Developmental outcomes and courses following PAE were assessed using rmANCOVAs, controlling for relevant confounders (socioeconomic status (SES), birth weight, and maternal psychopathology). RESULTS: Neurophysiological impairments emerged for exposed children in the form of diminished attentional resource recruiting in childhood and adolescence (reduced go-P3 amplitudes) with no differences in performance. Neuropsychological testing showed a reduced IQ score for both time points with dose-dependent effects in childhood. Clinical ADHD symptoms were not significantly affected. CONCLUSION: Subclinical PAE, as determined by meconium EtG, has negative developmental consequences on cognitive function that persist from childhood to adolescence. These findings suggest that there is no safe limit for alcohol consumption during pregnancy and that more thorough screening of alcohol consumption during pregnancy is necessary for early identification and treatment of at-risk children.


Subject(s)
Glucuronates , Meconium , Prenatal Exposure Delayed Effects , Infant, Newborn , Humans , Female , Adolescent , Pregnancy , Child , Prenatal Exposure Delayed Effects/diagnosis , Ethanol , Alcohol Drinking/adverse effects , Cognition
4.
IEEE Trans Vis Comput Graph ; 30(1): 1085-1094, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37871087

ABSTRACT

Over the last decade merge trees have been proven to support a plethora of visualization and analysis tasks since they effectively abstract complex datasets. This paper describes the ExTreeM-Algorithm: A scalable algorithm for the computation of merge trees via extremum graphs. The core idea of ExTreeM is to first derive the extremum graph G of an input scalar field f defined on a cell complex K, and subsequently compute the unaugmented merge tree of f on G instead of K; which are equivalent. Any merge tree algorithm can be carried out significantly faster on G, since K in general contains substantially more cells than G. To further speed up computation, ExTreeM includes a tailored procedure to derive merge trees of extremum graphs. The computation of the fully augmented merge tree, i.e., a merge tree domain segmentation of K, can then be performed in an optional post-processing step. All steps of ExTreeM consist of procedures with high parallel efficiency, and we provide a formal proof of its correctness. Our experiments, performed on publicly available datasets, report a speedup of up to one order of magnitude over the state-of-the-art algorithms included in the TTK and VTK-m software libraries, while also requiring significantly less memory and exhibiting excellent scaling behavior.

5.
Eur Eat Disord Rev ; 32(2): 281-297, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37850962

ABSTRACT

BACKGROUND: Anorexia nervosa (AN) is associated with altered processing of disorder-relevant stimuli. Event-related potentials (ERP) - such as the Late Positive Potential (LPP) - give information about the underlying mechanisms of central nervous stimulus processing. METHODS: Patients with AN (22 adolescents, 23 adults) and healthy controls (HCs; 17 adolescents, 24 adults) were included. Neutral, low, and high calorie food-images were rated for valence and arousal; EEG activity was recorded and LPPs (early: 350-700 ms; late: 800-1200 ms) were extracted. Effects of patient status, age group, and stimulus category were analyzed via mixed 2 × 2 × 3-AN(C)OVAs. RESULTS: Patients with AN rated high calorie stimuli lower in valence and higher in arousal than HCs. Controlling for hunger, food stimuli elicited higher early LPPs than neutral ones in patients and HCs. For the late LPP, patients with AN showed larger amplitudes. CONCLUSION: Results suggest a highly automatic attentional bias towards low-calorie foods. Patients with AN seem to have more intense cognitive processing independent of stimulus material. More research is needed to validate and clarify differences between early and late LPP measures as well as the operationalization and relevance of hunger status.


Subject(s)
Anorexia Nervosa , Electroencephalography , Adult , Humans , Adolescent , Emotions/physiology , Anorexia Nervosa/psychology , Evoked Potentials/physiology , Food
6.
Comput Struct Biotechnol J ; 21: 5451-5462, 2023.
Article in English | MEDLINE | ID: mdl-38022691

ABSTRACT

Applications of lipases in low-water environments are found across a broad range of industries, including the pharmaceutical and oleochemical sectors. This includes condensation reactions in organic solvents where the enzyme activity has been found to depend strongly on both the solvent and the water activity (aw). Despite several experimental and computational studies, knowledge is largely empirical, and a general predictive approach is much needed. To close this gap, we chose native Candida antarctica lipase B (CALB) and two mutants thereof and used molecular dynamics (MD) simulations to gain a molecular understanding of the effect of aw on the specific activity of CALB in hexane. Based on the simulations, we propose four criteria to understand the performance of CALB in organic media, which is supported by enzyme kinetics experiments. First, the lipase must be stable in the organic solvent, which was the case for native CALB and the two mutants studied here. Secondly, water clusters that form and grow close to the active site must not block the path of substrate molecules into the active site. Thirdly, the lipase's lid must not cover the active site. Finally, mutations and changes in aw must not disrupt the geometry of the active site. We show that mutating specific residues close to the active site can hinder water cluster formation and growth, making the lipase resistant to changes in aw. Our computational screening criteria could potentially be used to screen in-silico designed variants, so only promising candidates could be pushed forward to characterisation.

7.
Angew Chem Int Ed Engl ; 62(49): e202314597, 2023 12 04.
Article in English | MEDLINE | ID: mdl-37873919

ABSTRACT

The sirtuins are NAD+ -dependent lysine deacylases, comprising seven isoforms (SIRT1-7) in humans, which are involved in the regulation of a plethora of biological processes, including gene expression and metabolism. The sirtuins share a common hydrolytic mechanism but display preferences for different ϵ-N-acyllysine substrates. SIRT7 deacetylates targets in nuclei and nucleoli but remains one of the lesser studied of the seven isoforms, in part due to a lack of chemical tools to specifically probe SIRT7 activity. Here we expressed SIRT7 and, using small-angle X-ray scattering, reveal SIRT7 to be a monomeric enzyme with a low degree of globular flexibility in solution. We developed a fluorogenic assay for investigation of the substrate preferences of SIRT7 and to evaluate compounds that modulate its activity. We report several mechanism-based SIRT7 inhibitors as well as de novo cyclic peptide inhibitors selected from mRNA-display library screening that exhibit selectivity for SIRT7 over other sirtuin isoforms, stabilize SIRT7 in cells, and cause an increase in the acetylation of H3 K18.


Subject(s)
Sirtuin 1 , Sirtuins , Humans , Sirtuin 1/metabolism , Sirtuins/chemistry , Acetylation , Hydrolysis , Protein Isoforms/metabolism
8.
J Clin Med ; 12(19)2023 Sep 23.
Article in English | MEDLINE | ID: mdl-37834786

ABSTRACT

Prenatal androgen exposure modulates the development of the brain, with lasting effects on its function and behavior over the infant's life span. Environmental factors during pregnancy, in particular maternal stress, have been shown to influence the androgen load of the unborn child. We here addressed the research gap on whether a mindfulness intervention or a pregnancy education administered to pregnant women more affects the androgen exposure of the unborn child (quantified by the proxies of second-to-fourth digit length ratio (2D:4D) and anogenital distance assessed one year after delivery and at delivery, respectively). Moreover, we tested the mindfulness intervention's effects on maternal perceived stress, anxiety, depressiveness, and mindfulness. Pregnant women (gestation weeks 8-14) were randomized to a 15-week app-based mindfulness-oriented intervention (N = 72) or a pregnancy education intervention (control condition; N = 74). The mindfulness-oriented group did not significantly differ from the pregnancy education group in infants' 2D:4D or anogenital distance (partial η2 ≤ 0.01) or in maternal stress, anxiety, depressiveness, or mindfulness. However, the descriptive results indicate that across pregnancy, stress and anxiety decreased and mindfulness increased in both groups. Overall, this study did not show that the mindfulness intervention (relative to the pregnancy education) reduced the prenatal androgen exposure of the unborn children or improved the maternal outcomes significantly.

9.
Children (Basel) ; 10(9)2023 Sep 05.
Article in English | MEDLINE | ID: mdl-37761470

ABSTRACT

Anorexia Nervosa (AN) and Attention Deficit Hyperactivity Disorder (ADHD) are frequent mental disorders in child and adolescent psychiatry. Comorbidity of these disorders is, however, rare among minors. Thus, little is known about their mutual impact on illness development as well as diagnostic and therapeutic influencing factors. We report the case of a 10-year old girl with AN and massive underweight. At the age of 5, ADHD had been diagnosed. Application of ADHD-specific medication had been refused by her caregiver. As of 3rd grade, hyperkinetic symptoms were significantly reduced, which was later linked to beginning AN-induced weight loss. At inpatient admission, no clinically relevant ADHD-related symptoms were present. Accompanying weight gain, rather 'sudden' appearance of attention difficulties, motoric hyperactivity and impulsivity were reported, widely impairing our patient's schoolwork and further daily life. Methylphenidate medication showed good clinical response and tolerability. We hypothesize that the former massive underweight had suppressed ADHD-specific behaviour. AN with significant weight loss could possibly mask hyperkinetic symptoms in children. Thus, sufficient clinical diagnostics and intense monitoring during ED treatment are required. Physicians and therapists should be sensitized for interactions in the joint occurrence of these mental disorders among minors.

10.
Healthcare (Basel) ; 11(15)2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37570360

ABSTRACT

Family influences on child quality of life (QoL) are increasingly understood. Parenting behavior and parent individual psychopathology are among the established predictors of offspring mental health. However, literature often addresses these factors as 'parental', lacking further gender-specific differentiation while predominantly studying maternal aspects. Social and biological fathers are still underrepresented in family research. The aim of this study was to analyze paternal contributions to child well-being. A total of 197 father/mother-dyads gave a standardized self-report on parenting behavior and their own psychopathology at child primary school age (t1; 6-10 y). Ratings were compared mutually and associated with child self-rated QoL at t1 and adolescence (t2; 12-14 y). Fathers and mothers differed in psychopathology and most parenting behavior dimensions (positive parenting, involvement, responsible parenting, poor monitoring, and corporal punishment). Father psychopathology made a relevant predictive contribution to girls' QoL at t2. Boys' t1 QoL was significantly influenced by maternal parenting factors (positivity and corporal punishment). Compared to mothers, fathers are faced with different individual stressors; paternal parenting behavior is different, while fathers' influences are significant, particularly for daughters. Father-addressed pre- and intervention programs in child psychotherapeutic treatment are of high relevance.

11.
Pharmaceutics ; 15(7)2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37514040

ABSTRACT

We performed molecular dynamics simulations of Reteplase in the presence of different excipients to study the stabilizing mechanisms and to identify the role of excipients during freeze drying. To simulate the freeze-drying process, we divided the process into five distinct steps: (i) protein-excipient formulations at room temperature, (ii) the ice-growth process, (iii)-(iv) the partially solvated and fully dried formulations, and (v) the reconstitution. Furthermore, coarse-grained (CG) simulations were employed to explore the protein-aggregation process in the presence of arginine. By using a coarse-grained representation, we could observe the collective behavior and interactions between protein molecules during the aggregation process. The CG simulations revealed that the presence of arginine prevented intermolecular interactions of the catalytic domain of Reteplase, thus reducing the aggregation propensity. This suggests that arginine played a stabilizing role by interacting with protein-specific regions. From the freeze-drying simulations, we could identify several protein-specific events: (i) collapse of the domain structure, (ii) recovery of the drying-induced damages during reconstitution, and (iii) stabilization of the local aggregation-prone region via direct interactions with excipients. Complementary to the simulations, we employed nanoDSF, size-exclusion chromatography, and CD spectroscopy to investigate the effect of the freeze-drying process on the protein structure and stability.

12.
Mol Pharm ; 20(6): 2951-2965, 2023 06 05.
Article in English | MEDLINE | ID: mdl-37146162

ABSTRACT

Therapeutic proteins can be challenging to develop due to their complexity and the requirement of an acceptable formulation to ensure patient safety and efficacy. To date, there is no universal formulation development strategy that can identify optimal formulation conditions for all types of proteins in a fast and reliable manner. In this work, high-throughput characterization, employing a toolbox of five techniques, was performed on 14 structurally different proteins formulated in 6 different buffer conditions and in the presence of 4 different excipients. Multivariate data analysis and chemometrics were used to analyze the data in an unbiased way. First, observed changes in stability were primarily determined by the individual protein. Second, pH and ionic strength are the two most important factors determining the physical stability of proteins, where there exists a significant statistical interaction between protein and pH/ionic strength. Additionally, we developed prediction methods by partial least-squares regression. Colloidal stability indicators are important for prediction of real-time stability, while conformational stability indicators are important for prediction of stability under accelerated stress conditions at 40 °C. In order to predict real-time storage stability, protein-protein repulsion and the initial monomer fraction are the most important properties to monitor.


Subject(s)
Antibodies, Monoclonal , Chemometrics , Humans , Protein Stability , Antibodies, Monoclonal/chemistry , Protein Unfolding , Protein Conformation , Drug Stability
13.
Children (Basel) ; 10(5)2023 May 12.
Article in English | MEDLINE | ID: mdl-37238414

ABSTRACT

Pregnancy anamnesis is a crucial part of child and adolescent psychiatry diagnostics. In previous works, the reliability of retrospective maternal self-report on perinatal characteristics was heterogeneous. This prospective longitudinal study aimed to evaluate women's recall of prenatal events in a within-subject design. A sample of 241 women gave a self-report on prenatal alcohol, smoking, partnership quality, pregnancy satisfaction, and obstetric complications during the 3rd trimester (t0), childhood (t1, 6-10 y), and adolescence (t2, 12-14 y). The intra-individual agreement was examined. The t0-t1-(t2) agreement was poor to substantial; this was highest for smoking and worst for obstetric complications, followed by alcohol (Fleiss' κ = 0.719 to -0.051). There were significant t0-t1-(t2) differences for all pregnancy variables (p < 0.017), except for 3rd trimester satisfaction (p = 0.256). For alcohol (t0 25.8%, t1 17.4%, t2 41.0%) and smoking (t0 11.9%, t1 16.4%, t2 22.6%), the highest self-reported rates were found during adolescence. During childhood, fewer obstetric complications (t0 84.9%, t1 42.2%) and worse partnerships were reported (t0 M = 8.86, t1 M = 7.89). Thought to be due to social stigmata and memory effects, pregnancy self-reports cannot be precisely reproduced. Creating a respectful and trusting atmosphere is essential for mothers to give honest self-reports that are in the best interest of their children.

14.
Structure ; 31(6): 689-699.e6, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37119821

ABSTRACT

Tryptophan hydroxylase 2 (TPH2) catalyzes the rate-limiting step in serotonin biosynthesis in the brain. Consequently, regulation of TPH2 is relevant for serotonin-related diseases, yet the regulatory mechanism of TPH2 is poorly understood and structural and dynamical insights are missing. We use NMR spectroscopy to determine the structure of a 47 N-terminally truncated variant of the regulatory domain (RD) dimer of human TPH2 in complex with L-Phe, and show that L-Phe is the superior RD ligand compared with the natural substrate, L-Trp. Using cryo-EM, we obtain a low-resolution structure of a similarly truncated variant of the complete tetrameric enzyme with dimerized RDs. The cryo-EM two-dimensional (2D) class averages additionally indicate that the RDs are dynamic in the tetramer and likely exist in a monomer-dimer equilibrium. Our results provide structural information on the RD as an isolated domain and in the TPH2 tetramer, which will facilitate future elucidation of TPH2's regulatory mechanism.


Subject(s)
Serotonin , Tryptophan Hydroxylase , Humans , Tryptophan Hydroxylase/genetics , Tryptophan Hydroxylase/chemistry , Ligands
15.
Early Hum Dev ; 181: 105776, 2023 06.
Article in English | MEDLINE | ID: mdl-37084692

ABSTRACT

BACKGROUND: A lot of studies use the second-to-fourth digit length ratio (2D:4D) as a biomarker for intrauterine androgen load to predict behavioral and mental health problems. Thus, knowledge of 2D:4D's metric properties, namely reliability and validity, is essential. METHOD: 2D:4D handscans were available from 149 adolescents (M = 13.32 years, SD = 0.35) and their mothers. For 88 adolescents, there were also primary-school age handscans (M = 7.87 years, SD = 0.68). Prenatal risks for the 1st to 3rd trimesters were recorded during the 3rd trimester of pregnancy (alcohol exposition: meconium biomarker and maternal self-report; nicotine exposition: maternal self-report; maternal depressive symptoms and subjective stress: questionnaires). RESULTS: The 2D:4D ratio was highly stable from childhood to early adolescence. However, both developmental and sex effects were present: The 2D:4D ratio increased with age and was higher in adolescent girls vs. boys. Significant 2D:4D mother-child associations were found for girls. Significant main effects could be found for the prenatal risk factors alcohol (self-report) and nicotine consumption. CONCLUSION: In line with earlier studies, the 2D:4D biomarker proved to be an inter-individually stable measure with an intra-individual increase from childhood to early adolescence. Sex differences in adolescence and associations with maternal prenatal health behaviour underline the validity of the biomarker. Findings on heritability emphasize the importance of interpreting 2D:4D results in a sex-specific manner.


Subject(s)
Androgens , Nicotine , Child , Pregnancy , Humans , Male , Adolescent , Female , Reproducibility of Results , Mothers , Biomarkers , Fingers
16.
Behav Sci (Basel) ; 13(3)2023 Mar 02.
Article in English | MEDLINE | ID: mdl-36975240

ABSTRACT

In anorexia nervosa, aberrant emotional reactions toward body stimuli have been discussed. We investigated heart rate as a physiological marker when viewing body stimuli and hypothesized altered HR reactions toward those highly significant and emotional stimuli in anorexia nervosa. In total, 37 anorexia nervosa patients and 43 control participants viewed pictures of women of five different weight categories, while their cardiac activity was recorded. R-R intervals following picture onset were determined, and means were calculated for three distinct time periods. The overall change in HR relative to baseline across all picture categories was greater in the patient group than in the control group (significant effect of "group", p = 0.002, partial η2 = 0.120). A significant decrease in HR 2 to 8 s after picture presentation was found for pictures of women of extreme weight in both participant groups (significant "category ∗ time segment interaction", p = 0.01, partial η2 = 0.037) and correlated with scores of sociocultural attitudes toward the appearance for the extremely underweight category (r = -0.33, p = 0.005). Therefore, differential HR reactions for anorexia nervosa patients and control participants were found for body stimuli in general. The highest HR decelerations in response to pictures of strongly underweight and overweight women may reflect emotional processes such as anxiety due to social comparison.

17.
J Am Chem Soc ; 145(8): 4882-4891, 2023 03 01.
Article in English | MEDLINE | ID: mdl-36802551

ABSTRACT

While α-, ß-, and γ-cyclodextrin (CD) are ubiquitous hosts employed by supramolecular chemists, δ-CD (formed from nine α-1,4-linked glucopyranose units) has received very little attention. α-, ß-, and γ-CD are the major products of the enzymatic breakdown of starch by cyclodextrin glucanotransferase (CGTase), but δ-CD forms only transiently in this reaction, as a minor component of a complex mixture of linear and cyclic glucans. In this work, we show how δ-CD can be synthesized in unprecedented yields by employing a bolaamphiphile template in an enzyme-mediated dynamic combinatorial library of cyclodextrins. NMR spectroscopy studies revealed that δ-CD can thread up to three bolaamphiphiles forming [2]-, [3]-, or [4]-pseudorotaxanes, depending on the size of the hydrophilic headgroup and the length of the alkyl chain axle. Threading of the first bolaamphiphile occurs in fast exchange on the NMR chemical shift time scale, while subsequent threading occurs in slow exchange. To extract quantitative information for 1:2 and 1:3 binding events occurring in mixed exchange regimes, we derived equations for nonlinear curve fitting that take into consideration both the chemical shift changes for species in fast exchange and the integrals for species in slow exchange to determine Ka1, Ka2, and Ka3. Template T1 could be used to direct the enzymatic synthesis of δ-CD due to the cooperative formation of a 1:2 complex─the [3]-pseudorotaxane δ-CD·T12. Importantly, T1 is recyclable. It can be readily recovered from the enzymatic reaction by precipitation and reused in subsequent syntheses enabling preparative-scale synthesis of δ-CD.


Subject(s)
Cyclodextrins , Cyclodextrins/chemistry , Glucans , Starch/chemistry , Glucosyltransferases/metabolism
18.
J Biomol Struct Dyn ; 41(11): 5007-5021, 2023 07.
Article in English | MEDLINE | ID: mdl-35612899

ABSTRACT

We have performed a series of multiple molecular dynamics (MD) simulations of glucagon-like peptide-1 (GLP-1) and acylated GLP-1 analogues in complex with the endogenous receptor (GLP-1R) to obtain a molecular understanding of how fatty acid (FA) chain structure, acylation position on the peptide, and presence of a linker affect the binding. MD simulations were analysed to extract heatmaps of receptor-peptide interaction patterns and to determine the free energy of binding using the molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) approach. The extracted free energies from MM-PBSA calculations are in qualitative agreement with experimentally determined potencies. Furthermore, the interaction patterns seen in the receptor-GLP-1 complex simulations resemble previously reported binding interactions validating the simulations. Analysing the receptor-GLP-1 analogue complex simulations, we found that the major differences between the systems stem from FA interactions and positioning of acylation in the peptide. Hydrophobic interactions between the FA chain and a hydrophobic patch on the extracellular domain contribute significantly to the binding affinity. Acylation on Lys26 resulted in noticeably more interactions between the FA chain and the extracellular domain hydrophobic patch than found for acylation on Lys34 and Lys38, respectively. The presence of a charged linker between the peptide and FA chain can potentially stabilise the complex by forming hydrogen bonds to arginine residues in the linker region between the extracellular domain and the transmembrane domain. A molecular understanding of the fatty acid structure and its effect on binding provides important insights into designing acylated agonists for GLP-1R.Communicated by Ramaswamy H. Sarma.


Subject(s)
Glucagon-Like Peptide 1 , Glucagon , Glucagon-Like Peptide 1/chemistry , Peptides/chemistry , Molecular Dynamics Simulation , Protein Domains
19.
Protein Sci ; 32(2): e4556, 2023 02.
Article in English | MEDLINE | ID: mdl-36571497

ABSTRACT

For improved control of biomaterial property design, a better understanding of complex coacervation involving anionic polysaccharides and proteins is needed. Here, we address the initial steps in condensate formation of ß-lactoglobulin A (ß-LgA) with nine defined alginate oligosaccharides (AOSs) and describe their multivalent interactions in structural detail. Binding of AOSs containing four, five, or six uronic acid residues (UARs), either all mannuronate (M), all guluronate (G), or alternating M and G embodying the block structural components of alginates, was characterized by isothermal titration calorimetry, nuclear magnetic resonance spectroscopy (NMR), and molecular docking. ß-LgA was highly multivalent exhibiting binding stoichiometries decreasing from five to two AOSs with increasing degree of polymerization (DP) and similar affinities in the mid micromolar range. The different AOS binding sites on ß-LgA were identified by NMR chemical shift perturbation analyses and showed diverse compositions of charged, polar and hydrophobic residues. Distinct sites for the shorter AOSs merged to accommodate longer AOSs. The AOSs bound dynamically to ß-LgA, as concluded from saturation transfer difference and 1 H-ligand-targeted NMR analyses. Molecular docking using Glide within the Schrödinger suite 2016-1 revealed the orientation of AOSs to only vary slightly at the preferred ß-LgA binding site resulting in similar XP glide scores. The multivalency coupled with highly dynamic AOS binding with lack of confined conformations in the ß-LgA complexes may help explain the first steps toward disordered ß-LgA alginate coacervate structures.


Subject(s)
Alginates , Lactoglobulins , Lactoglobulins/chemistry , Alginates/chemistry , Alginates/metabolism , Molecular Docking Simulation , Binding Sites , Polysaccharides , Oligosaccharides
20.
J Clin Med ; 11(23)2022 Dec 06.
Article in English | MEDLINE | ID: mdl-36498814

ABSTRACT

Beside somatic strains of congenital heart diseases (CHD), affected children often show developmental impairments in the long term. Ventricular septal defect (VSD) is the most common congenital heart defect and early surgical repair is associated with positive somatic outcomes. However, psychological adjustment is of lifelong relevance. We investigated 24 children with a surgically-corrected isolated VSD and their mothers from primary school (6-9 years) to adolescence (10-14 years) and compared them to controls. Both times, mothers reported child internalizing/externalizing problems, mothers and children rated child quality of life, and children performed neurodevelopmental tests. Adolescents also rated internalizing/externalizing problems themselves, and their hair cortisol levels were analyzed. Maternal anxiety and proactive parenting behavior were considered as moderators. Results revealed no group differences in child neurodevelopment (language, cognition), externalizing problems, and cortisol levels at any time. In reports from mothers, internalizing problems (depression, anxiety) were elevated in children with a VSD at both times-when mothers reported anxiety symptoms themselves. In adolescent reports, VSD patients' quality of life was increased and internalizing problems were decreased-proactive parenting behavior went along with decreased symptoms in VSD-affected adolescents and with increased symptoms in controls. The findings pronounce the crucial role of parenting behavior and the influence of maternal anxieties on child mental health after surgical VSD repair and might highlight the need for parent-centered interventions.

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