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The absolute performance of any all-atom molecular dynamics simulation is typically limited by the length of the individual timesteps taken when integrating the equations of motion. In the GROMACS simulation software, it has for a long time been possible to use so-called virtual sites to increase the length of the timestep, resulting in a large gain of simulation efficiency. Up until now, support for this approach has in practice been limited to the standard 20 amino acids however, shrinking the applicability domain of virtual sites. MkVsites is a set of python tools which provides a convenient way to obtain all parameters necessary to use virtual sites for virtually any molecules in a simulation. Required as input to MkVsites is the molecular topology of the molecule(s) in question, along with a specification of where to find the parent force field. As such, MkVsites can be a very valuable tool suite for anyone who is routinely using GROMACS for the simulation of molecular systems.

Medium-chain fatty acid-based permeation enhancers (PEs) have gained significant attention due to their potential application in various industries, including within the pharmaceutics sector as absorption enhancers for, e.g., peptide drugs. In this study, we performed computational experiments to investigate the impact of two different PEs, capric acid and Salcaprozate sodium (SNAC), at three different concentrations (0%, 30%, 50%), on the structural properties of a bilayer consisting of 70% 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) and 30% cholesterol. We employed coarse-grained molecular dynamics simulations first to explore the interactions of the PEs with lipid bilayers at the molecular level and then to examine the consequences of these interactions for the permeability of three different peptides (octreotide, desmopressin, and triptorelin). We employed umbrella sampling simulations to obtain the permeability rates of the PEs at several concentrations and of the peptides in the absence and presence of the two PEs, also at different concentrations. We observed that the impact on the membrane structural properties changed with increasing PE concentration. We also found that the effective permeability values increased with increasing PE concentration. However, the permeability values were significantly higher (6-7 orders of magnitude) for capric acid than for SNAC, which we argue is mainly because capric acid has more pronounced effects on the structural properties of the membrane. Peptide permeability also increased with increasing PE concentration. The Peff values followed the trend: octreotide > triptorelin > desmopressin across all systems. For each peptide, the lowest Peff values were observed in the no-PE systems, while the highest values were observed in the systems with 50% capric acid. Capric acid exhibited an increasing trend in Peff values with higher concentrations within the membrane. In contrast, the peptide Peff values in the SNAC systems were similar between the 30% and 50% concentrations, aligning with the trends observed in free energy profiles and the membrane structural characteristics. Thus, for SNAC, there seems to be a concentration where the permeability-enhancing effect plateaus. With these results, we hope to pave the way for more knowledge-based design of pharmaceutical dosage forms that involve PEs for increasing transcellular peptide permeability, considering the differences in compatibility between PEs and peptides, and the apparent synergistic effect of combining PEs.

Oral administration of drugs is generally considered convenient and patient-friendly. However, oral administration of biological drugs exhibits low oral bioavailability (BA) due to enzymatic degradation and low intestinal absorption. A possible approach to circumvent the low BA of oral peptide drugs is to coformulate the drugs with permeation enhancers (PEs). PEs have been studied since the 1960s and are molecules that enhance the absorption of hydrophilic molecules with low permeability over the gastrointestinal epithelium. In this study, we investigated the impact of six PEs on the structural properties of a model membrane using molecular dynamics (MD) simulations. The PEs included were the sodium salts of the medium chain fatty acids laurate, caprate, and caprylate and the caprylate derivative SNAC─all with a negative charge─and neutral caprate and neutral sucrose monolaurate. Our results indicated that the PEs, once incorporated into the membrane, could induce membrane leakiness in a concentration-dependent manner. Our simulations suggest that a PE concentration of at least 70–100 mM is needed to strongly affect transcellular permeability. The increased aggregation propensity seen for neutral PEs might provide a molecular-level mechanism for the membrane disruptions seen at higher concentrations in vivo. The ability for neutral PEs to flip-flop across the lipid bilayer is also suggestive of possible intracellular modes of action other than increasing membrane fluidity. Taken together, our results indicate that MD simulations are useful for gaining insights relevant to the design of oral dosage forms based around permeability enhancer molecules.

Permeability enhancer-based formulations offer a promising approach to enhance the oral bioavailability of peptides. We used all-atom molecular dynamics simulations to investigate the interaction between two permeability enhancers (sodium caprate, and SNAC), and four different peptides (octreotide, hexarelin, degarelix, and insulin), in the presence of taurocholate, an intestinal bile salt. The permeability enhancers exhibited distinct effects on peptide release based on their properties, promoting hydrophobic peptide release while inhibiting water-soluble peptide release. Lowering peptide concentrations in the simulations reduced peptide-peptide interactions but increased their interactions with the enhancers and taurocholates. Introducing peptides randomly with enhancer and taurocholate molecules yielded dynamic molecular aggregation, and reduced peptide-peptide interactions and hydrogen bond formation compared to peptide-only systems. The simulations provided insights into molecular-level interactions, highlighting the specific contacts between peptide residues responsible for aggregation, and the interactions between peptide residues and permeability enhancers/taurocholates that are crucial within the mixed colloids. Therefore, our results can provide insights into how modifications of these critical contacts can be made to alter drug release profiles from peptide-only or mixed peptide-PE-taurocholate aggregates. To further probe the molecular nature of permeability enhancers and peptide interactions, we also analyzed insulin secondary structures using Fourier transform infrared spectroscopy. The presence of SNAC led to an increase in beta-sheet formation in insulin. In contrast, both in the absence and presence of caprate, alpha-helices, and random structures dominated. These molecular-level insights can guide the design of improved permeability enhancer-based dosage forms, allowing for precise control of peptide release profiles near the intended absorption site. Molecular-level insights can guide the design of improved permeability enhancer-based dosage forms, allowing for precise control of peptide release profiles near the intended absorption site.

RNA Recognition Motifs (RRMs) are essential post-transcriptional regulators of gene expression in eukaryotic cells. The Human Musashi-1 (MSI-1) is an RNA-binding protein that recognizes (G/A)U1-3AGU and UAG sequences in diverse RNAs through two RRMs and regulates the fate of target RNA.

Here, we combined structural biology and computational approaches to analyse the binding of the RRM domains of human MSI-1 with single-stranded and structured RNAs ligands. We used our recently developed computational tool RRMScorer to design a set of mutants of the MSI-1 protein to bind novel RNA sequences to alter the binding selectivity. The in-silico predictions of the designed protein-RNA interactions are assessed by NMR and SPR. These experiments also are used to study the competition of the two RRM domains of MSI-1 for the same binding site within linear and harpin RNA. Our experimental results confirm the in-silico designed interactions, thus opening the way for the development of new biomolecules for in vitro and in vivo studies and downstream applications.

The kinetics of the interaction between Musashi-1 (MSI1) and RNA have been characterized using surface plasmon resonance biosensor analysis. Truncated variants of human MSI1 encompassing the two homologous RNA recognition motifs (RRM1 and RRM2) in tandem (aa 1-200), and the two RRMs in isolation (aa 1-103 and aa 104-200, respectively) were produced. The proteins were injected over sensor surfaces with immobilized RNA, varying in sequence and length, and with one or two RRM binding motifs. The interactions of the individual RRMs with all RNA variants were well described by a 1:1 interaction model. The interaction between the MSI1 variant encompassing both RRM motifs was bivalent and rapid for all RNA variants. Due to difficulties in fitting this complex data using standard procedures, we devised a new method to quantify the interactions. It revealed that two RRMs in tandem resulted in a significantly longer residence time than a single RRM. It also showed that RNA with double UAG binding motifs and potential hairpin structures forms less stable bivalent complexes with MSI1 than the single UAG motif containing linear RNA. Substituting the UAG binding motif with a CAG sequence resulted in a reduction of the affinity of the individual RRMs, but for MSI1, this reduction was strongly enhanced, demonstrating the importance of bivalency for specificity. This study has provided new insights into the interaction between MSI1 and RNA and an understanding of how individual domains contribute to the overall interaction. It provides an explanation for why many RNA-binding proteins contain dual RRMs.

Reporter systems are widely used to study biomolecular interactions and processes in vivo, representing one of the basic tools used to characterize synthetic regulatory circuits. Here, we developed a method that enables the monitoring of RNA–protein interactions through a reporter system in bacteria with high temporal resolution. For this, we used a Real-Time Protein Expression Assay (RT-PEA) technology for real-time monitoring of a fluorescent reporter protein, while having bacteria growing on solid media. Experimental results were analyzed by fitting a three-variable Gompertz growth model. To validate the method, the interactions between a set of RNA sequences and the RNA-binding protein (RBP) Musashi-1 (MSI1) were evaluated, as well as the allosteric modulation of the interaction by a small molecule (oleic acid). This new approach proved to be suitable to quantitatively characterize RNA–RBP interactions, thereby expanding the toolbox to study molecular interactions in living bacteria, including allosteric modulation, with special relevance for systems that are not suitable to be studied in liquid media.

Background: The emergence of β-lactamase-producing bacteria has led to the use of β-lactam (BL) antibiotic and β-lactamase inhibitor (BLI) drug combinations. Despite therapeutic drug monitoring (TDM) being endorsed for BLs, the impact of TDM on BLIs remains unclear.

Objectives: Evaluate whether BLIs are available in effective exposures at the site of infection and assess if TDM of BLIs could be of interest.

Methods: Population pharmacokinetic models for 9 BL and BLI compounds were used to simulate drug concentrations at infection sites following EMA-approved dose regimens, considering plasma protein binding and tissue penetration. Predicted target site concentrations were used for probability of target attainment (PTA) analysis.

Results: Using EUCAST targets, satisfactory (≥90%) PTA was observed for BLs in patients with typical renal clearance (CrCL of 80 mL/min) across various sites of infection. However, results varied for BLIs. Avibactam achieved satisfactory PTA only in plasma, with reduced PTAs in abdomen (78%), lung (73%) and prostate (23%). Similarly, tazobactam resulted in unsatisfactory PTAs in intra-abdominal infections (79%), urinary tract infections (64%) and prostatitis (34%). Imipenem-relebactam and meropenem-vaborbactam achieved overall satisfactory PTAs, except in prostatitis and high-MIC infections for the latter combination.

Conclusions: This study highlights the risk of solely relying on TDM of BLs, as this can indicate acceptable exposures of the BL while the BLI concentration, and consequently the combination, can result in suboptimal performance in terms of bacterial killing. Thus, dose adjustments also based on plasma concentration measurements of BLIs, in particular for avibactam and tazobactam, can be valuable in clinical practice to obtain effective exposures at the target site.

Purpose: To investigate the pharmacokinetics (PK) of ceftazidime-avibactam (CAZ-AVI) in critically ill patients undergoing continuous venovenous hemodiafiltration (CVVHDF), and compare with a general phase III trial population.

Methods: A prospective PK study was conducted in critically ill patients who received CVVHDF for acute kidney injury, treated with CAZ-AVI (1000/250 mg or 2000/500 mg q8h). Plasma and CVVHDF-circuit samples were collected to determine CAZ-AVI concentrations. Individual PK parameters at steady-state were estimated using non-compartmental analysis. For visual comparison, plasma concentrations from CVVHDF patients were overlaid with simulated data from patients not receiving CVVHDF based on previously developed population PK models.

Results: A total of 35 plasma samples and 16 CVVHDF-circuit samples were obtained from four patients, with two patients sampled on two separate occasions. Median total clearance and volume of distribution were 4.54 L/h and 73.2 L for CAZ and 10.5 L/h and 102 L for AVI, respectively. Median contribution of CVVHDF to total clearance was 19.8% for CAZ and 5.3% for AVI. Observed CAZ-AVI PK profiles were generally within the 90% confidence interval of model predictions, but the observed concentrations were notably lower early (0-2 h) and higher later (4-8 h) in the dosing interval, suggesting a higher volume of distribution.

Conclusions: These results suggest that the CAZ-AVI dose regimens used in this study can be applicable in critically ill patients undergoing CVVHDF, despite the different shape of the PK profiles observed in this population. Further research with a larger patient cohort is warranted to validate and refine these findings.

Background

The emergence of β-lactamase-producing bacteria limits the effectiveness of β-lactam (BL) antibiotics, and the combination with a β-lactamase inhibitor (BLI) aims to counteract this resistance. However, existing guidelines primarily focus on optimizing the dosing of BLs and do not adequately address the interaction between BLs and BLIs, leading to uncertain pharmacokinetic/pharmacodynamic (PK/PD) targets and potentially suboptimal dosing strategies.

Objectives

To investigate optimal PK/PD targets and dosing strategies for avibactam (BLI) combined with ceftazidime (BL) using mechanism-based PKPD models.

Methods

PK models for ceftazidime and avibactam were integrated with mechanism-based PKPD models for Gram-negative bacteria. Simulations explored dose regimens in mice and humans, evaluating PK/PD indices and computing the PTA for diverse dosing strategies and infusion modes.

Results

fAUC/MIC_CAZ/AVI was the most predictive index for avibactam against Enterobacteriaceae in both mice and humans, regardless of infusion mode. Against Pseudomonas aeruginosa, fT > C_T predicted efficacy in mice, while fAUC/MIC_CAZ/AVI and fCmax/MIC_CAZ/AVI were more predictive in humans, particularly for continuous infusion regimens. Higher PTAs were achieved with increased avibactam doses relative to ceftazidime, particularly with 1:1 and 2:1 ceftazidime:avibactam ratios. Continuous infusion improved PTA against P. aeruginosa but had limited impact on Enterobacteriaceae.

Conclusion

The PK/PD indices predictive of avibactam efficacy varied by species (mice and humans), bacterial strains, and mode of infusion. Dosing simulations suggest that increasing avibactam relative to ceftazidime and using continuous infusion regimens may enhance bacterial killing. These findings highlight the importance of refining dosing strategies for both components of the combination therapy.

BACKGROUND: Cerebral complications in preeclampsia are leading causes of maternal mortality worldwide but the underlying pathophysiology is largely unknown and a challenge to study. Using an in vitro model of the human blood brain barrier (BBB), we explored the role of vascular endothelial growth factor receptor 2 (VEGFR2) in preeclampsia.

METHODS: The human brain endothelial cell line (hCMEC/D3) cultured on Tranwells insert were exposed (12 h) to plasma from women with preeclampsia (n=28), normal pregnancy (n=28) and non-pregnant (n=16) controls. Transendothelial electrical resistance (TEER) and permeability to 70 kDa FITC-dextran were measured for assessment of BBB integrity. We explored possible underlying mechanisms, with focus on expression of tight junction proteins and phosphorylation of two tyrosine residues of VEGFR2, associated with vascular permeability and migration (pY951) and cell proliferation (pY1175). Plasma concentrations of soluble FMS like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF) were measured in order to establish correlations with in vitro results.

RESULTS: hCMEC/D3 exposed to plasma from women with preeclampsia exhibited reduced TEER and increased permeability to 70 kDa FITC-dextran. Further, these cells up-regulated the mRNA levels of VEGFR2, as well as pY951-VEGFR2; but reduced pY1175-VEGFR2 (p&0.05 in all cases). No difference in mRNA expression of tight junction protein was observed between gruops. There was no correlation between angiogenic biomarkers and BBB permeability.

CONCLUSION: We present a promising in vitro model of the BBB in preeclampsia. Selective tyrosine phosphorylation of VEGFR2 may participate in the increased BBB permeability in preeclampsia irrespective of plasma concentrations of angiogenic biomarkers.

Cerebral complications in preeclampsia contribute substantially to maternal mortality and morbidity. There is a lack of reliable and accessible predictors for preeclampsia-related cerebral complications. In this study, plasma from women with preeclampsia (n = 28), women with normal pregnancies (n = 28) and non-pregnant women (n = 16) was analyzed for concentrations of the cerebral biomarkers neurofilament light (NfL), tau, neuron-specific enolase (NSE) and S100B. Then, an in vitro blood-brain barrier (BBB) model, based on the human cerebral microvascular endothelial cell line (hCMEC/D3), was employed to assess the effect of plasma from the three study groups. Transendothelial electrical resistance (TEER) was used as an estimation of BBB integrity. NfL and tau are proteins expressed in axons, NSE in neurons and S100B in glial cells and are used as biomarkers for neurological injury in other diseases such as dementia, traumatic brain injury and hypoxic brain injury. Plasma concentrations of NfL, tau, NSE and S100B were all higher in women with preeclampsia compared with women with normal pregnancies (8.85 vs. 5.25 ng/L, p < 0.001; 2.90 vs. 2.40 ng/L, p < 0.05; 3.50 vs. 2.37 mu g/L, p < 0.001 and 0.08 vs. 0.05 mu g/L, p < 0.01, respectively). Plasma concentrations of NfL were also higher in women with preeclampsia compared with non-pregnant women (p < 0.001). Higher plasma concentrations of the cerebral biomarker NfL were associated with decreased TEER (p = 0.002) in an in vitro model of the BBB, a finding which indicates that NfL could be a promising biomarker for BBB alterations in preeclampsia.

Importance  Gestational hypertension, preeclampsia, and eclampsia are established risk factors for stroke and dementia later in life. Whether these pregnancy complications are associated with an increased risk of new-onset neurological disorders within months to years after giving birth is not known.

Objective  To explore whether gestational hypertension, preeclampsia, and eclampsia are associated with new-onset migraine, headache, epilepsy, sleep disorder, or mental fatigue within months to years after giving birth.

Design, Setting, and Participants  In this register-based cohort study, exposures were identified in the Swedish Medical Birth Register from 2005 to 2018. Follow-up was conducted using the National Patient Register, containing diagnoses from specialized inpatient and outpatient care. Follow-up started 42 days after delivery and continued until the first event, death, emigration, or the end of the follow-up period (2019). The risk was calculated with Cox regression analysis and expressed as adjusted hazard ratio (aHR) with a 95% CI. Through the Swedish Medical Birth Register, 659 188 primiparous women with singleton pregnancies between 2005 and 2018 were identified. Women with a diagnosis of chronic hypertension (n = 4271) or a prepregnancy neurological disorder (n = 6532) were excluded. The final study population included 648 385 women. Data analyses were conducted in 2023.

Exposures  Gestational hypertension, preeclampsia, and eclampsia.

Main outcome  The primary outcome was a composite neurological outcome of migraine, headache, epilepsy, sleep disorder, or mental fatigue.

Results  The study included 648 385 women with a mean age of 28.5 (SD, 5.0) years at the time of their first pregnancy. Women with gestational hypertension (n = 11 133), preeclampsia (n = 26 797), and eclampsia (n = 625) all had an association with increased risk for a new-onset neurological disorder compared with women with normotensive pregnancies. The aHR for gestational hypertension was 1.27 (95% CI, 1.12-1.45), 1.32 (95% CI, 1.22-1.42) for preeclampsia, and 1.70 (95% CI, 1.16-2.50) for eclampsia. When exploring individual outcomes, women with eclampsia were associated with more than a 5 times increased risk of epilepsy (aHR, 5.31; 95% CI, 2.85-9.89).

Conclusion and Relevance  In this study, gestational hypertension, preeclampsia, and eclampsia were associated with an increased risk of new-onset migraine, headache, epilepsy, sleep disorder, or mental fatigue within months to years after giving birth. Guidelines recommend follow-up after delivery for women with gestational hypertension and preeclampsia for their increased risk of cardiovascular disease. At these visits, caregivers should also pay attention to persisting or new-onset of neurological symptoms, since this group of women appears to be vulnerable to developing or experiencing neurological disorders.

An approximately 40-km long high-resolution reflection seismic profile (P3) was acquired in the metropolitan area of Seoul in South Korea for the purpose of fault system imaging in a highly noisy and challenging urban environment. Two 12t seismic vibrators (mini-vibs) were used as the seismic source. Data were recorded using a dual element seismic spread; 20 m spaced 421 wireless seismic recorders connected to 10 Hz geophones and 20 micro-electro-mechanical-based landstreamer sensors (2 m sensor spacing) attached to one of the vibrators. The purpose of the dual spread employed was to delineate both near-surface and deep structures. The processing results show good quality and the processing work was complemented by different analysis to further constraints the geological interpretation. The survey results provide evidence for the 3D geometry of three fault systems, including Chugaryeong, Pocheon, and Wangsukcheon faults. A gently westerly dipping set of reflectivity underlying a dome-shaped package of reflectivity is interpreted as a fault, and could project to the known surface position of the Pocheon fault. The dome-shaped reflectivity is interpreted as folded and faulted dyke or sill systems. Downward continuation of the interpreted fault intersects the sub-vertical Chugaryeong fault in a zone where the current seismicity is observed, suggesting that these two major fault systems may have jointly evolved in the form of splay faults. Reflections from the Wangsukcheon fault are also present in the data and interpreted to dip approximately 60 degrees to the east, in an opposite direction to the two other faults.

The increasing global interest in geologic carbon storage as a feasible way of reducing CO2 atmospheric levels requires extensive onshore high-resolution seismic investigations to characterize suitable storage sites, for example, close to major CO2 emitters. To partly address this challenge and to acquire quality data at shallower and greater depths in a cost- and time-effective approach, a tailored acquisition scheme is adopted and tested at a candidate site in Stenlille, Denmark. The survey aims to understand whether an anticline reservoir structure known to exist at a 1000 m depth can serve for long-term CO2 storage and presents the structural integrity for this purpose. The data are recorded using a combination of nodal arrays, spaced at 10 m in a fixed geometry, and a set of more closely (2 m) spaced digital recorders, mounted on a landstreamer, which was moved at each shot location. Two 12 t mini vibrators are used as seismic sources. The nodal and landstreamer data sets are compared and combined into a unique data set for reflection imaging purposes along five profiles with a total length of approximately 12 km. The seismic sections obtained using this tailored combination of different recorders provide images of the entire shallow and deeper structures with an unprecedented resolution at the different depth levels necessary to assess the full potential of the suggested CO2 storage reservoir. The results significantly increase the existing knowledge of the extent and structural closure of the reservoir as well as a possible fault, all of which are critical for future risk analysis and planning of the storage.

Strong global actions for climate change include carbon capture and storage (CCS) as a feasible solution to reach carbon neutrality and raise opportunities for detailed subsurface investigations. An acquisition set-up designed for onshore-offshore zones was maximized for wide-scale high-resolution structural imaging and implemented to cover a domal structure of interest for CCS utilization close to the town of Havns & oslash; (Denmark). The challenges of the combined acquisition and processing of land and marine multisensor data along a 42 km seismic profile are analyzed, the suggested solutions are applied, and the limitations are discussed. On the onshore side, a nodal array and a seismic landstreamer system were simultaneously used, whereas along the transition zone, a marine seismic streamer and ocean-bottom seismometers were added to record the seismic response generated by two seismic vibrator sources. The adopted sensing domains (velocity, acceleration, and pressure) were studied, and different processing steps were evaluated to enable their processing and subsequent data set merging. Results suggest, as the best approach, a separate prestack processing of the different data sets and the computation of new geometries and new surface-consistent residual static correction after their merging. The data acquired in the transition zone illuminate, for the first time, the subsurface geology of the region, delineating an expected domal closure. The final seismic section shows high continuity of the reflections with good resolution along the entire profile, identifying the main reservoir structure and the surrounding areas, which are important to ensure reservoir integrity and safe exploitation over longer time scales. Shallow and deep reflections are consistent with the stratigraphic column from a well log near the profile. The presented study shows a comprehensive workflow for processing such a multisensor data set in onshore and transition zone settings.

In various conflict contexts where the state is unable to maintain security and public order, non-state armed groups (NSAGs) and the United Nations (UN) conduct their activities alongside one another. While previous research has focused on hostile relations between the UN and NSAGs, less attention has been given to collaborative interactions. This paper aims to address this research gap by formulating a novel conceptual typology of NSAG-UN interactions in the context of a peace operation. The typological framework comprises two-dimensions: firstly, the thematic field of interaction including human rights, humanitarian needs and governance, security, and political processes and, secondly, the nature of interaction ranging from confrontation to cooperation. Based on the typology, interaction activities between the UN and NSAGs in two peacekeeping operations-the UN Operation in C & ocirc;te d'Ivoire (UNOCI) and the UN Multidimensional Integrated Stabilization Mission in Mali (MINUSMA)-are systematically documented and described. While both cases show confrontation in the security field, UNOCI also commonly cooperated with NSAGs on security-related issues; MINUSMA instead cooperated with NSAGs primarily regarding the political process. The analysis further proposes factors that may explain such variation, including institutional arrangements and NSAG characteristics. The conceptual framework presented in this paper is crucial in advancing knowledge about an empirical phenomenon that we know little about and that has important implications for different forms of "local" engagement in peace operations and the effectiveness of UN policies and practices.

There is an urgent need for efficient solutionprocessable p-type semiconductors. Copper(I) iodide (CuI) has attracted attention as a potential candidate due to its good electrical properties and ease of preparation. However, its carrier dynamics still need to be better understood. Carrier dynamics after bandgap excitation yielded a convoluted signal of free carriers (positive signal) and a negative feature, which was also present when the material was excited with sub-bandgap excitation energies. This previously unseen feature was found to be dependent on measurement temperature and attributed to negative photoconductivity. The unexpected signal relates to the formation of polarons or strongly bound excitons. The possibility of coupling CuI to plasmonic sensitizers is also tested, yielding positive results. The outcomes mentioned above could have profound implications regarding the applicability of CuI in photocatalytic and photovoltaic systems and could also open a whole new range of possible applications.

Photoredox catalysis's relevance in organic synthesis research and innovation will increase in the coming decades. However, the processes rely almost exclusively on expensive noble metal complexes, most notably iridium complexes, to absorb light and transfer a single charge to a substrate or a catalyst to initiate cascade transformations. Light-triggered plasmon resonances generate a non-Fermi-Dirac energy distribution with many hot carriers that decay in similar to 1 ps. Their ultrafast relaxation makes performing single electron transfer (SET) transformations challenging. Herein, a novel photosystem is proposed based on surface-modified gold nanoparticles (aka plasmon "molecularization"), which improved charge separation and, more importantly, enabled SET reactions, expanding the portfolio of photocatalysts available for photoredox catalysis. The photosystem was made into an electrode, permitting its use in photoelectrochemical arrangements that leverage electro- and photo-chemical approaches' benefits and chemical engineering solutions, helping the synthetic chemistry efforts towards greener synthesis and synthesis of more complex structures on a scale.

Increased attention has been directed toward generating nonequilibrium hot carriers resulting from the decay of collective electronic oscillations on metal known as surface plasmons. Despite numerous experimental endeavors, demonstrating hot carrier-mediated photocatalysis without a heating contribution has proven challenging, particularly for single electron transfer reactions where the thermal contribution is generally detrimental. An innovative engineering solution is proposed to enable single electron transfer reactions with plasmonics. It consists of a photoelectrode designed as an energy filter and photocatalysis performed with light function modulation instead of continuously. The photoelectrode, consisting of FTO/TiO₂ amorphous (10 nm)/Au nanoparticles, with TiO₂ acting as a step-shape energy filter to enhance hot electron extraction and charge-separated state lifetime. The extracted hot electrons were directed toward the counter electrode, while the hot holes performed a single electron transfer oxidation reaction. Light modulation prevented local heat accumulation, effectively decoupling hot carrier catalysis from the thermal contribution.

Exchange of viral segments between one or more influenza virus subtypes can contribute to a shift in virulence and adaptation to new hosts. Among several influenza subtypes, H9N2 is widely circulating in poultry populations worldwide and has the ability to infect humans. Here, we studied the reassortant compatibility between chicken H9N2 with N1-N9 gene segments of wild bird origin, either with an intact or truncated stalk. Naturally occurring amino acid deletions in the NA stalk of the influenza virus can lead to increased virulence in both mallard ducks and chickens. Our findings show extended genetic compatibility between chicken H9Nx gene segments and the wild-bird NA with and without 20 amino acid stalk deletion. Replication kinetics in avian, mammalian and human cell lines revealed that parental chH9N2 and rH9N6 viruses with intact NA-stalk replicated significantly better in avian DF1 cells compared to human A549 cells. After introducing a stalk deletion, an enhanced preference for replication in mammalian and human cell lines could be observed for rH9N2(Delta)(H6), rH9N6(Delta) and rH9N9(Delta) compared to the parental chH9N2 virus. This highlights the potential emergence of novel viruses with variable phenotypic traits, warranting the continuous monitoring of H9N2 and co-circulating subtypes in avian hosts.

Shrews are primary hosts for mammalian hantaviruses and are thus considered to be important reservoirs for viruses, similar to rodents and bats. To explore the diversity of hantaviruses in Swedish common shrews (Sorex araneus), we investigated lung tissues from shrews collected between 2015 and 2017. The collection took place at three separate locations in south-central Sweden. Screening for hantaviruses was performed using two different approaches: i) A total of 110 common shrews were investigated for hantaviruses by a pan-hanta L-gene RT-PCR, and Sanger sequencing was performed on the 13 positive samples. ii) In addition, 88 RNA samples were pooled into eight libraries subjected to RNA sequencing. The RNA sequencing data analysis, which focused specifically on identifying hantaviruses, revealed two divergent hantaviruses: the complete genome of an Altai-like virus and the partial genome of Seewis virus. Evolutionary analysis revealed that Swedish Altai-like viruses are closely related to Russian Altai viruses but distinct from Finnish strains. On the contrary, Swedish Seewis virus shares closer ancestry with Finnish Seewis virus strains. Given that these viruses were identified in several libraries, Seewis virus and Altai virus are likely circulating in Swedish common shrews. Supported by earlier studies, common shrews are probably the natural host for at least these two distinct hantaviruses.

In 2018, a local case of nephropathia epidemica was reported in Scania, southern Sweden, more than 500 km south of the previously known presence of human hantavirus infections in Sweden. Another case emerged in the same area in 2020. To investigate the zoonotic origin of those cases, we trapped rodents in Ballingsl & ouml;v, Norra Sandby, and S & ouml;rby in southern Sweden during 2020-2021. We found Puumala virus (PUUV) in lung tissues from 9 of 74 Myodes glareolus bank voles by screening tissues using a hantavirus pan-large segment reverse transcription FOR. Genetic analysis revealed that the PUUV strains were distinct from those found in northern Sweden and Denmark and belonged to the Finnish PUUV lineage. Our findings suggest an introduction of PUUV from Finland or Karelia, causing the human PUUV infections in Scania. This discovery emphasizes the need to understand the evolution, cross-species transmission, and disease outcomes of this newly found PUUV variant.

Researchers have conducted a lot of research into policies regulating commercialsex. This study is a scoping review aiming to characterize the research field as wellas finding research gaps and suggest directions for future research. Nine electronicdatabases and a key journal (Sexuality Research and Social Policy) were searchedusing Boolean operators to identify studies containing “prostitution AND policy”or “sex work AND policy” in the title and/or abstract. A total of 3663 studies wereidentified, and of them, 351 were deemed eligible after duplicates were removed andthe title and abstract had been assessed according to the study’s inclusion criteria.The studies on sex work policy were often conducted in English-speaking countries,the majority of which were about streetwalkers, criminalization of sex work, andtrafficking policies. Interestingly, few empirical studies were conducted and stigma-tization was frequently mentioned. There is an unmet need for studies addressing thelived experiences of sex workers under the Swedish Model, as well as studies aboutmigrant sex workers and studies from Africa, Asia, and Latin America. Research-ers should direct additional efforts into understanding the lived experiences of sexworkers under the Swedish Model as well as into studies covering Africa, Asia, andLatin America.

Despite the increased popularity of exit programmes targeting people involved in sex work, the research community has yet not critically scrutinised policies that regulate these programmes. This study aimed to start filling this research gap by studying the example of Denmark, a country that has implemented exit programmes although sex work remains partly decriminalised since 1999. In specific, this study has analysed policy documents that were formulated by the government and four Danish municipalities in relation to the government's latest grant called ‘Exit Package for People in Prostitution’, which was issued in 2019 to finance municipal exit programmes running between 2020 and 2023. The key finding indicates that the ‘problem’ of sex work is the sex work of the ‘vulnerable’ sex workers. Their sex work must be reduced because they risk being seriously harmed by their sex work activities. Implications from the findings of the study are discussed.

Background

Insights into the immunological role of the gastrointestinal tract in autoimmune conditions have led to the investigation of diet as a potential adjunctive treatment option for juvenile idiopathic arthritis (JIA). The specific carbohydrate diet (SCD) has shown promising results. However, studies on participants’ experiences of dietary interventions in JIA are rare. In this study we investigated the experiences of children and parents’ who had participated in a four-week intervention with SCD aiming to examine the potential anti-inflammatory effects.

Objectives

To conduct a qualitative evaluation exploring children’s and parents’ experiences of the dietary intervention, how they navigated challenges, and their support requirements.

Methods

Semi-structured interviews were conducted with 12 children and 15 parents from 13 families, who were interviewed individually and together. The transcripts were analysed using systematic text condensation.

Results

Most participants interviewed found the intervention beneficial, with 12 out of 13 reporting positive effects, such as reduced pain and morning stiffness, and improved gastrointestinal function. Many participants reported being willing to repeat the intervention in the current form. Despite facing challenges, all children followed the diet for one to three months, with some continuing to follow a modified version. Facing the socio-emotional consequences of adhering to the diet was challenging for children. These were handled by focusing on the positive aspects and by relying on the supportive environment available. Parents struggled with practical issues since the diet required hard work, time, and money. Areas identified as requiring additional support include finding simple, quick, and child-friendly solutions, strengthening organizational food skills such as meal planning, and preparation prior to starting the intervention regarding socio-emotional aspects.

Conclusion

Navigating the dietary treatment was considered challenging, practically for the parents and socio-emotionally for the children. Based on the reported challenges and participants’ suggestions the intervention could be optimised by providing support and solutions in relation to the practical issues and better preparation regarding dealing with the socio-emotional consequences. Despite the difficulties, the participants reported overall positive experiences of, and attitudes towards, the current setup. Consequently, dietary interventions, such as the SCD, may be regarded as suitable targets for further research.

Diet is considered a key research priority for juvenile idiopathic arthritis (JIA), garnering considerable interest from affected families. Despite this, research studies focusing on dietary interventions remain scarce. The specific carbohydrate diet (SCD) has shown potential, however, its nutritional consequences and risks are not well understood. This study aims to describe and evaluate food and nutrient intakes in children with JIA adhering to the SCD and contextualize the results relative to recommendations and intakes in the general population. In a secondary analysis, food and nutrient intakes from three-day dietary records of ten children, following a four-week SCD intervention, were evaluated against the Nordic Nutrition Recommendations 2023 and Riksmaten Adolescents data (RMA) (n = 1282). All children following the SCD met the recommended minimum intake of fruit and vegetables of 500g/day, a stark contrast to the 6% in RMA. Median dietary fibre intake for the SCD was 26g/d, (IQR 21-33), compared to 16g/d (IQR 12-22) in RMA. Elevated saturated fatty acid (SFA) intake was observed in both groups, with the SCD group also consuming high amounts of red meat. Calcium was the sole nutrient for which the standard diet surpassed the SCD, as 9 out of 10 participants had inadequate intake. While children on the SCD showed a lower likelihood of nutrient inadequacy compared to the general population, inadequate calcium intake and elevated SFA and red meat consumption are concerning given known comorbidities in JIA. These results highlight the importance of disease-specific dietary guidance to ensure optimal support for patients and parents.

Whole-body positron emission tomography-computed tomography (PET-CT) imaging in oncology provides comprehensive information of each patient's disease status. However, image interpretation of volumetric data is a complex and time-consuming task. In this work, an image registration method targeted towards computer-aided voxel-wise analysis of whole-body PET-CT data was developed. The method used both CT images and tissue segmentation masks in parallel to spatially align images step-by-step. To evaluate its performance, a set of baseline PET-CT images of 131 classical Hodgkin lymphoma (cHL) patients and longitudinal image series of 135 head and neck cancer (HNC) patients were registered between and within subjects according to the proposed method. Results showed that major organs and anatomical structures generally were registered correctly. Whole-body inverse consistency vector and intensity magnitude errors were on average less than 5 mm and 45 Hounsfield units respectively in both registration tasks. Image registration was feasible in time and the nearly automatic pipeline enabled efficient image processing. Metabolic tumor volumes of the cHL patients and registration-derived therapy-related tissue volume change of the HNC patients mapped to template spaces confirmed proof-of-concept. In conclusion, the method established a robust point-correspondence and enabled quantitative visualization of group-wise image features on voxel level.

Background: Tumor heterogeneity is recognized as a predictor of treatment response and patient outcome. Quantification of tumor heterogeneity across all scales may therefore provide critical insight that ultimately improves cancer management.

Methods: An image registration-based framework for the study of tumor heterogeneity in whole-body images was evaluated on a dataset of 490 FDG-PET-CT images of lung cancer, lymphoma, and melanoma patients. Voxel-, lesion- and subject-level features were extracted from the subjects' segmented lesion masks and mapped to female and male template spaces for voxel-wise analysis. Resulting lesion feature maps of the three subsets of cancer patients were studied visually and quantitatively. Lesion volumes and lesion distances in subject spaces were compared with resulting properties in template space. The strength of the association between subject and template space for these properties was evaluated with Pearson's correlation coefficient.

Results: Spatial heterogeneity in terms of lesion frequency distribution in the body, metabolic activity, and lesion volume was seen between the three subsets of cancer patients. Lesion feature maps showed anatomical locations with low versus high mean feature value among lesions sampled in space and also highlighted sites with high variation between lesions in each cancer subset. Spatial properties of the lesion masks in subject space correlated strongly with the same properties measured in template space (lesion volume, R = 0.986, p < 0.001; total metabolic volume, R = 0.988, p < 0.001; maximum within-patient lesion distance, R = 0.997, p < 0.001). Lesion volume and total metabolic volume increased on average from subject to template space (lesion volume, 3.1 +/- 52 ml; total metabolic volume, 53.9 +/- 229 ml). Pair-wise lesion distance decreased on average by 0.1 +/- 1.6 cm and maximum within-patient lesion distance increased on average by 0.5 +/- 2.1 cm from subject to template space.

Conclusions: Spatial tumor heterogeneity between subsets of interest in cancer cohorts can successfully be explored in whole-body PET-CT images within the proposed framework. Whole-body studies are, however, especially prone to suffer from regional variation in lesion frequency, and thus statistical power, due to the non-uniform distribution of lesions across a large field of view.

Electrospinning is a technique used to fabricate polymer fibers in micro- and nanoscales. Due to the large distance between the nozzle and collector, there is a limited positioning accuracy of electrospun fibers. To enhance the possibility of fabricating structures with micrometer placement, an electroprinting technique has been developed. By reducing the distance between the nozzle and the collector it is demonstrated that it is possible to get an improved control over fiber positioning which gives a possibility to fabricate designed 3D structures at the micron scale. In this study, cellulose acetate (CA) has been selected as a biomaterial to advance the 3D printing of membranes with possible use in separation applications. Various parameters, such as CA concentration and molecular weight, printing speed, printing pattern, applied voltage, etc. are evaluated with respect to printing control. Results indicate that by optimizing the printing parameters it is possible to print structures with inter- fiber distances down to 3 mu m and fiber diameters at a sub-mu m scale. This electroprinting development is promising for the fabrication of customized separation membranes. However, printing speed still remains a challenge.

3D printing is envisioned to play an important role in the production of membranes for e.g., water purification and bio-separation applications due to the prospect of creating new and cleverly designed structures. Among different 3D printing techniques, direct ink writing offers the opportunity to print a wide variety of materials with high-detail resolution. There is a range of parameters that need to be optimized in order to develop robust printing techniques at that scale. In this study, cellulose acetate (CA), which is a biocompatible material, has been used as an ink. In order to examine the printability and the possibility of printing features as small as a few mu m, nozzles with different diameters and inks with varying amounts and molecular weights of CA were investigated. Findings in this study indicate that, depending on the wetting on the underlaying structure, the nozzle's internal and external diameter affects the detail resolution of the printed structure. Different inks result in different widths of printed strands and generally a higher amount and higher molecular weights of CA results in higher detail resolution. However, too high amount of CA and molecular weight will increase the clogging risk in the nozzle. In this study, the internal size of the nozzle was 3 mu m, and by selecting a suitable ink, it was possible to print strands down to 1 mu m size and 6 mu m inter-strand distance in the air, bridging supports with limited sagging. Furthermore, wall structures consisting of 300 layers, corresponding to about 300 mu m in total height, were successfully printed.

This study focuses on the fabrication and analysis of 3D-printed high detail resolution cellulose acetate (CA) structures, particularly examining their specific surface area per volume. While electrospinning is a widely used technique for creating nanofiber membranes with high, which is advantageous for applications like chromatography, the performance could be further improved by precisely controlling fiber placement. To further develop membranes, this research explores the use of electroprinting with small distances between nozzle and collector, here named near-collector electroprinting, to create 3D structures. By optimizing printing parameters, in particular the reduction of the nozzle-to-collector distance, 3D structures with precise fiber placement within a few micrometers were fabricated. The specific surface area per volume was calculated for both 3D-printed and electrospun filters. Results showed that 3D-printed structures with a 5 µm pitch achieved anper volume similar to electrospun filters. Incorporating polyethyleneimine (PEI) in the CA ink enabled the 3D-printed structures to gain ion binding capacity which was further investigated. This ion-exchange ability which integrated into the printing step, eliminating the need for a separate post-modification process in bio-separation applications. By switching the substrate voltage from positive to negative, relative to the grounded nozzle, the printed fiber diameter decreased substantially for the CA ink with PEI. The    for fibers of this material could therefore potentially be higher than that of electrospun membranes, provided that the fiber placement control can be maintained at an order of magnitude higher printing speed than presently possible. These findings suggest that near-collector electroprinted CA structures offer potential improvements in membrane design and performance, making them a promising alternative to traditional electrospun membranes for bio-separation applications.

The fabrication of scaffolds that replicate the structural complexity of native tissues is essential for advancing tissue engineering. This study explores near-collector electroprinting, a 3D printing technique to create structured scaffolds with controlled spacing of µm fibers down to 5 µm pitch. Human mesenchymal stromal cells (hMSCs) cultured on electroprinted cellulose acetate (CA) scaffolds exhibited high viability, and fiber spacing playing a crucial role in regulating cell adhesion, alignment, and bridging behavior. Scaffolds with many-layer and small pitches (20 µm) facilitated enhanced cellular connectivity, while larger pitches led to more random distribution. Also, lignin, a naturally occurring biopolymer with antibacterial and antioxidant properties, was incorporated into the scaffold to demonstrate the possibility of printing composite materials and evaluating its antimicrobial potential. The preliminary results indicate that CA-lignosolfunate (derivative of lignin) scaffolds reduce bacterial colony formation. These findings establish near-collector electroprinting as a scalable and versatile method for potential applications in wound healing and infection-resistant biomaterials.

In recent years, the application of machine learning in program verification, and the embedding of programs to capture semantic information, has been recognised as an important tool by many research groups. Learning program semantics from raw source code is challenging due to the complexity of real-world programming language syntax and due to the difficulty of reconstructing long-distance relational information implicitly represented in programs using identifiers. Addressing the first point, we consider Constrained Horn Clauses (CHCs) as a standard representation of program verification problems, providing a simple and programming language-independent syntax. For the second challenge, we explore graph representations of CHCs, and propose a new Relational Hypergraph Neural Network (R-HyGNN) architecture to learn program features.

We introduce two different graph representations of CHCs. One is called constraint graph (CG), and emphasizes syntactic information of CHCs by translating the symbols and their relations in CHCs as typed nodes and binary edges, respectively, and constructing the constraintsas abstract syntax trees. The second one is called control- and data-flow hypergraph (CDHG), and emphasizes semantic information of CHCs by representing the control and data flow through ternary hyperedges.

We then propose a new GNN architecture, R-HyGNN, extending Relational Graph Convolutional Networks, to handle hypergraphs. To evaluate the ability of R-HyGNN to extract semantic information from programs, we use R-HyGNNs to train models on the two graph representations, and on five proxy tasks with increasing difficulty, using benchmarks from CHC-COMP 2021 as training data. The most difficult proxy task requires the model to predict the occurrence of clauses in counter-examples, which subsumes satisfiability of CHCs. CDHG achieves 90.59% accuracy in this task. Furthermore, R-HyGNN has perfect predictions on one of the graphs consisting of more than 290 clauses. Overall, our experiments indicate that R-HyGNN can capture intricate program features for guiding verification problems.

The Relational Hyper-Graph Neural Network (R-HyGNN) was introduced in [1] to learn domain-specific knowledge from program verification problems encoded in Constrained Horn Clauses (CHCs). It exhibits high accuracy in predicting the occurrence of CHCs in counterexamples. In this research, we present an R-HyGNN-based framework called MUSHyperNet. The goal is to predict the Minimal Unsatisfiable Subsets (MUSes) (i.e., unsat core) of a set of CHCs to guide an abstract symbolic model checking algorithm. In MUSHyperNet, we can predict the MUSes once and use them in different instances of the abstract symbolic model checking algorithm. We demonstrate the efficacy of MUSHyperNet using two instances of the abstract symbolic modelchecking algorithm: Counter-Example Guided Abstraction Refinement (CEGAR) and symbolic model-checking-based (SymEx) algorithms. Our framework enhances performance on a uniform selection of benchmarks across all categories from CHC-COMP, solving more problems (6.1% increase for SymEx, 4.1% for CEGAR) and reducing average solving time (13.3% for SymEx, 7.1% for CEGAR).

This paper proposes a Graph Neural Network-guided algorithm for solving word equations, based on the well-known Nielsen transformation for splitting equations.The algorithm iteratively rewrites the first terms of each side of an equation, giving rise to a tree-like search space.The choice of path at each split point of the tree significantly impacts solving time, motivating the use of Graph Neural Networks (GNNs) for efficient split decision-making.Split decisions are encoded as multi-classification tasks, and five graph representations of word equations are introduced to encode their structural information for GNNs.The algorithm is implemented as a solver named DragonLi.Experiments are conducted  on artificial and real-world benchmarks. The algorithm performs particularly well on satisfiable problems. For single word equations, DragonLi can solve significantly more problems than well-established string solvers.For the conjunction of multiple word equations, DragonLi is competitive with state-of-the-art string solvers.

Heart failure affects 2-3% of adult Western population. Prevalence of heart failure with preserved left ventricular (LV) ejection fraction (HFpEF) increases. Studies suggest HFpEF patients to have altered myocardial structure and functional changes such as incomplete relaxation and increased cardiac stiffness. We hypothesised that patients undergoing elective coronary bypass surgery (CABG) with HFpEF characteristics would show distinctive gene expression compared to patients with normal LV physiology. Myocardial biopsies for mRNA expression analysis were obtained from sixteen patients with LV ejection fraction >= 45%. Five out of 16 patients (31%) had echocardiographic characteristics and increased NTproBNP levels indicative of HFpEF and this group was used as HFpEF proxy, while 11 patients had Normal LV physiology. Utilising principal component analysis, the gene expression data clustered into two groups, corresponding to HFpEF proxy and Normal physiology, and 743 differentially expressed genes were identified. The associated top biological functions were cardiac muscle contraction, oxidative phosphorylation, cellular remodelling and matrix organisation. Our results also indicate that upstream regulatory events, including inhibition of transcription factors STAT4, SRF and TP53, and activation of transcription repressors HEY2 and KDM5A, could provide explanatory mechanisms to observed gene expression differences and ultimately cardiac dysfunction in the HFpEF proxy group.

New or mild heart failure (HF) is mainly caused by left ventricular dysfunction. We hypothesised that gene expression differ between the left (LV) and right ventricle (RV) and secondly by type of LV dysfunction. We compared gene expression through myocardial biopsies from LV and RV of patients undergoing elective coronary bypass surgery (CABG). Patients were categorised based on LV ejection fraction (EF), diastolic function and NT-proBNP into pEF (preserved; LVEF ≥ 45%), rEF (reduced; LVEF < 45%) or normal LV function. Principal component analysis of gene expression displayed two clusters corresponding to LV and RV. Up-regulated genes in LV included natriuretic peptides NPPA and NPPB, transcription factors/coactivators STAT4 and VGLL2, ion channel related HCN2 and LRRC38 associated with cardiac muscle contraction, cytoskeleton, and cellular component movement. Patients with pEF phenotype versus normal differed in gene expression predominantly in LV, supporting that diastolic dysfunction and structural changes reflect early LV disease in pEF. DKK2 was overexpressed in LV of HFpEF phenotype, potentially leading to lower expression levels of β-catenin, α-SMA (smooth muscle actin), and enhanced apoptosis, and could be a possible factor in the development of HFpEF. CXCL14 was down-regulated in both pEF and rEF, and may play a role to promote development of HF.

Background

Epicardial adipose tissue (EAT) surrounds the heart and is hypothesised to play a role in the development of heart failure (HF). In this study, we first investigated the differences in gene expression between epicardial adipose tissue (EAT) and subcutaneous adipose tissue (SAT) in patients undergoing elective coronary artery bypass graft (CABG) surgery (n = 21; 95% male). Secondly, we examined the association between EAT and SAT in patients at risk for HF stage A (n = 12) and in pre-HF patients, who show signs but not symptoms of HF, stage B (n = 9).

Results

The study confirmed a distinct separation between EAT and SAT. In EAT 17 clusters of genes were present, of which several novel gene modules are associated with characteristics of HF. Notably, seven gene modules showed significant correlation to measures of HF, such as end diastolic left ventricular posterior wall thickness, e’_mean, deceleration time and BMI. One module was particularly distinct in EAT when compared to SAT, featuring key genes such as FLT4, SEMA3A, and PTX3, which are implicated in angiogenesis, inflammation regulation, and tissue repair, suggesting a unique role in EAT linked to left ventricular dysfunction. Genetic expression was compared in EAT across all pre-HF and normal phenotypes, revealing small genetic changes in the form of 18 differentially expressed genes in ACC/AHA Stage A vs. Stage B.

Conclusions

The roles of subcutaneous and epicardial fat are clearly different. We highlight the gene expression difference in search of potential modifiers of HF progress. The true implications of our findings should be corroborated in other studies since HF ACC/AHA stage B patients are common and carry a considerable risk for progression to symptomatic HF.

Background: Iron deficiency (ID) is associated with adverse prognosis in patients with heart failure. This study aims to investigate the relationship between ID and expression of genes involved in iron metabolism in human myocardium and skeletal muscle, focusing on Transferrin 1 receptor (TfR1), the main pathway of cellular iron uptake.

Methods: Patients undergoing elective CABG were assessed prior to surgery with echocardiography and serum iron parameters. Core needle biopsies were collected from the left and right ventricle (LV, RV), the right atrium and intercostal skeletal muscle (SM). Gene expression analyses were done by mRNA sequencing.

Results: Of 69 patients (median age 69 years, 91% men), 28% had ID. 26% had HFrEF, 25% had HFpEF phys-iology according to echocardiographic findings and NT-proBNP levels, and 49% had normal LV function. The expression of TfR1 was increased in patients with ID compared to patients without ID in ventricular tissue (p = 0.04) and in intercostal SM (p = 0.01). The increase in TfR1 expression in LV and RV was more pronounced when analysing patients with absolute ID (S-Ferritin<100 mu g/L). Analysing the correlation between various iron pa-rameters, S-Ferritin levels showed the strongest correlation with TfR1 expression. There was no correlation with NT-proBNP levels and no difference in TfR1 expression between different HF phenotypes.

Conclusions: In patients undergoing elective CABG we found an association between ID and increased TfR1 expression in myocardium regardless of LV function, indicating physiologically upregulated TfR1 expression in the presence of ID to restore intracellular iron needs.

Pharmacies are currently unable to stock proper oral dosage forms for pediatric populations. This leads to manipulation of medications or the need to compound specialized medications, which can be a time-consuming process. Using Semisolid Extrusion (SSE) additive manufacturing (AM), specialized medications can be produced in an expedited process from off-the shelf medication in a hospital or outpatient pharmacy setting. In this study, tablets with a desired dose of 5 mg of metoprolol tartrate derived from commercial Seloken™ 50 mg tablets were 3D printed in a hospital setting. Validation testing was done on five batches, highlighting tablets with a high uniformity in mass and dimension, drug content, acceptable microbial assays, and prolonged release during in-vitro analysis. The average drug content found for the tablets was within ±6% of 5 mg for all batches produced. Comparisons were done between the SSE tablets and capsules produced in an external compounding facility, highlighting several positive aspects of SSE-produced tablets beyond simply shortening the production timeline. The SSE tablets printed in this study are characterized by their smaller size, enhanced prolonged release properties, and more uniform drug content across the tested samples. Additionally, interviews with pharmaceutical professionals were conducted to determine the positive aspects of SSE and further improvements to bring this technique as seamlessly as possible into the pharmacy. This study underscores the feasibility of employing SSE in the production of specialized medications within a hospital environment. Furthermore, it highlights the methodological advantages SSE offers over existing production standards, demonstrating its potential to improve pharmaceutical manufacturing in healthcare settings.

Dose-adjustment is a very common practice in pharmacies, with accuracy particularly relevant for medications on a tapering schedule. Semisolid extrusion (SSE) has shown potential to provide a more accurate form of dose-adjustment than traditional methods (i.e. tablet splitting and liquid solutions). These methods, however, usually lack validation and quality assurance, as no validation is typically conducted post dose-adjustment. Machine learning (ML) based image analysis can provide this necessary validation. Fluoxetine-containing SSE tablets of three tapering steps were created to investigate with image analysis using a MLM. The tablets had a high degree of uniformity in mass and dimensional measurements. The average drug content of the SSE tablets was within ±3.5% of the desired dose for all tapering steps, showing higher accuracy than doses made via tablet splitting (±28.2% dose accuracy) and liquid solutions (±17.0% dose accuracy) produced by a licensed pharmacist. Utilizing a MLM for image analysis and images of tablets taken from the top and bottom of each tablet, the ability to categorize tablets based on the view of the tablet in the image (top or bottom of the tablet) and identification of the dose in the image showed over 99.87% confidence. The MLM also had the ability to identify mass outlier and non-outlier tablets well, with 90% correct identification of test images for tablets with a tablet height consistent with the average. Here, the need for more than one tablet viewpoint (i.e. greater variety of data), was more evident than for determining the drug dose, where the test tablets were all still identified correctly with over 99.65% confidence in all cases. This study identifies the feasibility of using a MLM to identify tablets as a means of validation based on images. 

Selective Laser Sintering (SLS) has the potential to offer a more accurate alternative to current-practice manipulation of oral dosage forms for pediatric, geriatric, and dysphagia-suffering patient groups. In order to create the best possible dosage forms for these patient groups, an in-depth look into how a dosage forms geometry impacts the overall properties is essential. In this study, the impact of geometry on SLS manufactured oral dosage forms on the tablet’s microstructure, actual-to-theoretical volume, mass deviation, disintegration, and dissolution was investigated. Three different shapes; cylinder, hollow cylinder, and conical frustum with similar surface area (SA), as well as three cylinders with different diameters, were investigated. The results indicate that the geometry has an impact on the mass uniformity, resultant volume, disintegration, and dissolution properties of the tablets. The mass uniformity analysis of the tablets provided the most variation between tablets of different sizes, with more uniformity for tablets with similar SA-to-volume ratio (SA/V). When examining the actual-to-theoretical volume of the tablets, a greater variance between the actual and theoretical volumes for shapes with higher overall SA was observed. The values found are approximately 1.05 for the three differently sized cylinders, 1.23 for the conical frustum, and 1.44 for the hollow cylinder, following this trend. Disintegration data supported a link between SA/V and average disintegration time, observed with the tablet of the highest SA/V disintegrating in 12 s and the tablet with the lowest SA/V disintegrating in 58 s. Dissolution results also indicated a strong dependence on SA/V. Hence, when novel ways to produce oral dosage form tablets become available by additive manufacturing, such as SLS, both geometry and SA/V must be taken into consideration in the tablet design process to ensure appropriate release kinetics and dosing standards.

The aim of this study is to investigate the influence of polymer chemistry on the properties of oral dosage forms produced using selective laser sintering (SLS). The dosage forms were printed using different grades of polyvinyl alcohol or copovidone in combination with indomethacin as the active pharmaceutical ingredient. The properties of the printed structures were assessed according to European Pharmacopoeia guidelines at different printing temperatures and laser scanning speeds in order to determine the suitable printing parameters.

The results of the study indicate that the chemical properties of the polymers, such as dynamic viscosity, degree of hydrolyzation, and molecular weight, have significant impact on drug release and kinetics. Drug release rate and supersaturation can be modulated by selecting the appropriate polymer type. Furthermore, the physical properties of the dosage forms printed under the same settings are influenced by the selected polymer type, which determines the ideal manufacturing settings.

This study demonstrates how the chemical properties of the polymer can determine the appropriate choice of manufacturing settings and the final properties of oral dosage forms produced using SLS.

Background: Unintended weight loss and nutritional problems are often seen in patients with head and neck cancer, but changes in lipid metabolism are poorly studied.

Aim/Objectives: The present study aimed to explore the longitudinal changes in circulating fatty acid (FA) composition in patients with head and neck cancer.

Materials and Methods: This study included 27 patients with head and neck cancer. Treatment consisted of single modality or combined modality treatments. The patients were assessed by repeated blood sampling and body weight assessments before treatment started and on three occasions after the start of treatment. FA profiling included gas chromatography analysis of unsaturated FAs and saturated FAs in serum.

Results: The values of three fatty acids - FA 14:0, FA 18:3n3, and FA 20:3n6 - changed in a specific pattern over the course of the study and the change in FA 14:0 correlated with weight changes.

Conclusions and significance: This study showed altered profiles of both saturated and unsaturated FAs. An improved understanding of the metabolic pathways in patients with head and neck cancer supports the development of better nutritional surveillance and nutritional treatments.

Simple Summary Cancer-associated malnutrition affects nutrient metabolism, including the metabolism of lipids. Toxicities associated with the treatment for head and neck cancer (HNC) may contribute to malnutrition through impaired oral intake and inflammation. Studies on lipid metabolism in patients with HNC are very limited. The anti-inflammatory effect of some fatty acids (FAs) is already proven in other cancers but the results of these studies in HNC are not consistent. This prospective study of 174 patients with HNC contributes to our knowledge of alterations in lipid metabolism following treatment for HNC and serves as basis for future research. Studies on fatty acids (FAs) in patients with head and neck cancer (HNC) are limited. We aimed to investigate the longitudinal changes of circulating FAs in patients with HNC and to examine potential correlations of FA changes with treatment. The secondary aims were to investigate correlations of FAs with cytokines and patient-related factors, and if any FAs correlated with disease recurrence or death. A total of 174 patients with HNC were included before treatment and followed-up at three time points after the start of the treatment through blood sampling and body weight measurements. Serum FA profiling was assessed by gas chromatography. The total follow-up time was 3 years. The levels of almost all FAs changed from baseline to 7 weeks. The change in FA 14:0 was associated with treatment and the change in 18:3n-6 was associated with the patients' pre-treatment BMI. FAs 14:0 and 18:0 were correlated with weight changes from baseline to 7 weeks. IL-6 was correlated with three FAs at 7 weeks and with two FAs at 1 year. Patients with higher levels 20:5n-3 at 3 months had a higher risk of all-cause death within 3 years (HR 2.75, 95% CI 1.22-6.21). Treatment, inflammation, and weight loss contributed in a complex manner to the altered FA profile in the studied cohort. The association between IL-6 and FAs in patients with HNC is in line with earlier studies and suggests the opportunity for regulating inflammation in HNC patients through modulation of FAs.

Aims

To examine the prognostic value of F-18 fluorodeoxyglucose (FDG) uptake in the bone marrow (BM) for disease recurrence and survival in patients with oropharyngeal squamous cell carcinoma (OP-SCC). The secondary aims were to evaluate the prognostic value of PET/CT parameters for the primary oropharyngeal tumor and total tumor burden, and to assess the correlation between FDG uptake variables and serum inflammatory markers.

Methods

This was an observational study of 91 patients with OP-SCC who underwent pretreatment FDG-PET/CT. The patients' blood samples were collected before treatment, and treatment was administered with the intention to cure. The median follow-up time was 40 months. The PET parameters measured were SUVmeanBM for the assessment of BM FDG uptake, SUVmean, SUVmax, total lesion glycolysis (TLG), and metabolic tumor volume (MTV) for the evaluation of primary oropharyngeal tumor and total tumor burden.

Blood samples were analyzed to determine each patient's white cell, red cell, and platelet cell counts, hemoglobin, and C-reactive protein level. In a subgroup of 33 patients, blood serum was analyzed to evaluate the expression of serum immune proteins using a proximity extension assay (Olink Proteomics).

Results

The univariate analysis revealed that SUVmeanBM and tumor-specific parameters (SUVmaxtumor, SUVmeantotal, SUVmaxtotal, MTVtotal, TLGtotal) were significantly associated with recurrence-free survival (RFS). After adjusting for age, sex, and stage only SUVmeanBM remained significantly associated with RFS. Spearman's correlation identified several correlations between PET parameters and inflammatory markers.

Conclusions

Our results show that several FDG-PET/CT parameters may have a prognostic value of treatment outcome in patients with OP-SCC. However, SUVmeanBM was the only independent PET parameter that showed a prognostic value for RFS in the study cohort. Moreover, the study findings might suggest an association between systemic inflammation and the metabolic activity in the BM.

Altered cortical excitability is reported in schizophrenia and depression, but findings are inconsistent. Prefrontal repetitive transcranial magnetic stimulation (TMS) induces short-term motor cortex excitability changes in healthy individuals, but its effect in schizophrenia and depression remains unexplored. Prefrontal intermittent theta burst stimulation (iTBS) improves negative symptoms in depression. Cortical excitability is a suggested biomarker for prefrontal iTBS response. We investigated if prefrontal iTBS affects motor cortex excitability in schizophrenia or depression. Secondary aims were to examine motor cortex excitability as a predictor of iTBS effect on negative symptoms in depression and to compare excitability between groups with schizophrenia, depression and healthy controls. TMS indices of cortical excitability − resting motor threshold, short-interval intracortical inhibition, intracortical facilitation and long-interval intracortical inhibition (LICI) − were pooled from previous studies, including an RCT evaluating iTBS for negative symptoms. The dataset comprised 44 patients with schizophrenia, 52 with depression, and 62 healthy controls. Regression models indicated no effect of active versus sham iTBS on any TMS index (all p ≥ .61). No baseline TMS index predicted negative symptom changes after iTBS in depression (all p ≥ .44). Patients with schizophrenia exhibited more pronounced LICI inhibition than the other groups (Mann-Whitney U = 1670, p < .001). LICI correlated with antipsychotic dose (Spearman's ρ = −0.28, p = .04). Prefrontal iTBS does not modify cortical excitability in schizophrenia or depression, nor does cortical excitability predict prefrontal iTBS effects on negative symptoms. The more pronounced LICI inhibition in schizophrenia may be related to the illness or medication.

INTRODUCTION: Gamma-aminobutyric acid (GABA) deficiency is suggested in depressive disorders, along with alterations in cortical excitability. However, whether these excitability changes are related to GABAA receptor availability is largely unknown. Our aim was to assess the correlation between these measures in depressed patients and healthy controls.

METHODS: Twenty-eight patients with a major depressive episode, measured before and after participating in a clinical trial with repetitive transcranial magnetic stimulation (TMS), and 15 controls underwent [11C]flumazenil positron emission tomography to assess GABAA receptor availability and paired pulse TMS (ppTMS) to evaluate cortical excitability. Both whole-brain voxel-wise GABAA receptor availability and mean values from left hand motor cortex and left paracentral lobule were correlated to the ppTMS outcomes: short-interval intracortical inhibition reflecting GABAA receptor activity, long-interval intracortical inhibition representing GABAB receptor activity, intracortical facilitation reflecting glutamate N-methyl-D-aspartate-receptor activity, as well as the resting motor threshold (rMT), considered a global measure of corticospinal excitability.

RESULTS: No significant differences in baseline GABAA receptor availability or cortical excitability were found between patients and controls. Additionally, no correlations were observed between baseline measurements of GABAA receptor availability and TMS outcomes. Changes in GABAA receptor availability in the hand motor cortex, between pre- and post-assessments, were inversely related to pre-post changes in hand rMT.

CONCLUSION: We found that a change in GABAA receptor availability was inversely related to a change in rMT, suggesting a link between GABA deficiency and increased rMT previously observed in depressive episodes. The results highlight the complex mechanisms governing cortical excitability measures and offer new insight into their properties during the depressive state.

Background: Describing the kinetics of cytokines involved as biomarkers of sepsis progression could help to optimise interventions in septic patients. This work aimed to quantitively characterise the cytokine kinetics upon exposure to live E. coli by developing an in silico model, and to explore predicted cytokine kinetics at different bacterial exposure scenarios.

Methods: Data from published in vivo studies using a porcine sepsis model were analysed. A model describing the time courses of bacterial dynamics, endotoxin (ETX) release, and the kinetics of TNF and IL-6 was developed. The model structure was extended from a published model that quantifies the ETX-cytokines relationship. An external model evaluation was conducted by applying the model to literature data. Model simulations were performed to explore the sensitivity of the host response towards differences in the input rate of bacteria, while keeping the total bacterial burden constant.

Results: The analysis included 645 observations from 30 animals. The blood bacterial count was well described by a one-compartment model with linear elimination. A scaling factor was estimated to quantify the ETX release by bacteria. The model successfully described the profiles of TNF, and IL-6 without a need to modify the ETXcytokines model structure. The kinetics of TNF, and IL-6 in the external datasets were well predicted. According to the simulations, the ETX tolerance development results in that low initial input rates of bacteria trigger the lowest cytokine release.

Conclusion: The model quantitively described and predicted the cytokine kinetics triggered by E. coli exposure. The host response was found to be sensitive to the bacterial exposure rate given the same total bacterial burden.

Objectives

Applying physiologically-based pharmacokinetic (PBPK) modelling in sepsis could help to better understand how PK changes are influenced by drug- and patient-related factors. We aimed to elucidate the influence of sepsis pathophysiology on the PK of meropenem by applying PBPK modelling.

Methods

A whole-body meropenem PBPK model was developed and evaluated in healthy individuals, and renally impaired non-septic patients. Sepsis-induced physiological changes in body composition, organ blood flow, kidney function, albumin, and haematocrit were implemented according to a previously proposed PBPK sepsis model. Model performance was evaluated, and a local sensitivity analysis was conducted.

Results

The model-predicted PK metrics (AUC, C_max, CL, V_ss) were within 1.33-fold-error margin of published data for 87.5% of the simulated profiles in healthy individuals. In sepsis, the model provided good predictions for literature-digitised average plasma and tissue exposure data, where the model-predicted AUC was within 1.33-fold-error margin for 9 out 11 simulated study profiles. Furthermore, the model was applied to individual plasma concentration data from 52 septic patients, where the model-predicted AUC, C_max, and CL had a fold-error ratio range of 0.98–1.12, with alignment of the predicted and observed variability. For V_ss, the fold-error ratio was 0.81, and the model underpredicted the population variability. CL was sensitive to renal plasma clearance, and kidney volume, whereas V_ss was sensitive to the unbound fraction, organ volume fraction of the interstitial compartment, and the organ volume.

Conclusions

These findings may be extended to more diverse drug types and support a more mechanistic understanding of the effect of sepsis on drug exposure.

In vitro time-kill curve (TKC) experiments are an important part of the pharmacokinetic- pharmacodynamic (PKPD) characterisation of antibiotics. Traditional TKCs use Mueller-Hinton broth (MHB), which lacks specific plasma components that could potentially influence the bacterial growth and killing dynamics, and affect translation to in vivo. This study aimed to evaluate the impact of plasma on the PKPD characterisation of two antibiotics; cefazolin and clindamycin. TKC experiments were conducted in pure MHB, and MHB spiked with 20% and 70% human plasma. Plasma protein binding (PPB) data were available, and a linear model described cefazolin's PPB, while clindamycin's PPB was best described by a second-order polynomial model. PKPD models were developed based on pure MHB and described drug effects using an E_max model, with consideration of adaptive resistance for cefazolin. The observed bacterial growth and killing in the plasma-spiked MHB TKC data was insufficiently described when applying the developed PPB and PKPD models. In plasma spiked MHB, a growth delay was observed, estimated to 0.25 h (20% plasma), or 2.90 h (70% plasma) for cefazolin, and 0.64 h (20% plasma), or 1.40 h (70% plasma) for clindamycin. Furthermore, the drug effect was higher than expected in plasma-spiked MHB, with bacterial stasis and/or killing at unbound concentrations below MIC, necessitating drug effect parameter scaling (C₅₀ for cefazolin, Hill coefficient for clindamycin). The findings highlight significant differences in bacterial growth and killing dynamics between pure MHB and plasma-spiked MHB and exemplify how PKPD modelling may be used to improve the translation of in vitro results.

The light-driven activation of halophosphines R₂PX (R = alkyl- or aryl, X = Cl, Br) by an Ir^III-based photocatalyst is described. It is shown that initially formed secondary phosphines R₂PH react readily with the remaining R₂PX in a parent–child reaction to form diphosphines R₂P–PR₂. Aryl-containing diphosphines can be further reduced to secondary phosphines R^Ar₂PH under identical photoredox conditions. Dihalophosphines RPX₂ are also activated by the photoredox protocol, giving rise to unusual 3-, 4-, and 5-membered cyclophosphines. Transient absorption studies show that the excited state of the Ir photocatalyst is reductively quenched by the DIPEA (N,N-di-iso-propylethylamine) electron donor. Electron transfer to R₂PX is however unexpectedly slow and cannot compete with recombination with the oxidized donor DIPEA^•+. As DIPEA is not a perfectly reversible donor, a small proportion of the total Ir^II population escapes recombination, providing the reductant for the observed transformations.

An efficient metal-free photocatalytic method for the alkylation of alkenes using accessible aliphatic alcohols as redox auxiliaries is presented. C-centered radicals can be generated under mild conditions and subsequently employed in a C(sp(3))-C(sp(3)) bond-forming process, which overall provides a C1 tethering strategy of nucleophiles and electrophiles. The optimized conditions accommodate various electron-deficient alkenes and secondary/tertiary alcohols, with applications in late-stage functionalization of natural products and pharmaceutically relevant compounds. Mechanistic investigations revealed a complex mechanistic manifold, including non-PCET fragmentation and concerted/stepwise PCET. Even though the previously thought PCET type mechanism is compatible with our observations, the non-PCET mechanism most probably constitutes a main pathway.

Immunostimulatory gene therapy using oncolytic viruses is currently evaluated as a promising therapy for cancer aiming to induce anti-tumour immunity. Here, we investigate the capacity of oncolytic adenoviruses (LOAd) and their transgenes to induce immunogenicity in the infected tumour cells. Oncolysis and death-related markers were assessed after infection of eight human solid cancer cell lines with different LOAd viruses expressing a trimerized, membrane-bound (TMZ)-CD40L, TMZ-CD40L and 41BBL, or no transgenes. The viruses induced transgene expression post infection before they were killed by oncolysis. Death receptors TRAIL-R1, TRAIL-R2 and Fas as well as immunogenic cell death marker calreticulin were upregulated in cell lines post infection. Similarly, caspase 3/7 activity was increased in most cell lines. Interestingly, in CD40+ cell lines there was a significant effect of the TMZ-CD40L-encoding viruses indicating activation of the CD40-mediated apoptosis pathway. Further, these cell lines showed a significant increase of calreticulin, and TRAIL receptor 1 and 2 post infection. However, LOAd viruses induced PD-L1 upregulation which may hamper anti-tumour immune responses. In conclusion, LOAd infection increased the immunogenicity of infected tumour cells and this was potentiated by CD40 stimulation. Due to the simultaneous PD-L1 increase, LOAd viruses may benefit from combination with antibodies blocking PD1/PD-L1.

Multiple myeloma (MM) is a plasma cell malignancy that is characterized by immune dysregulation. MM is commonly treated with immunomodulating agents, but still remains incurable. Herein, we proposed and evaluated immunostimulatory Lokon oncolytic adenoviruses (LOAd) for MM treatment. LOAd viruses are serotype 5/35 chimera, which enables infection of hematopoietic cells. Oncolysis is restricted to cells with a dysregulated retinoblastoma protein pathway, which is frequently observed in MM. Further, LOAd viruses are armed with human immunostimulatory transgenes: trimerized membrane-bound CD40L (LOAd700, LOAd703) and 4-1BBL (LOAd703). LOAd viruses were assessed in a panel of MM cell lines (ANBL-6, L363, LP-1, OPM-2, RPMI-8226, and U266-84). All cells were sensitive to infection, leading to viral replication and cell killing as analyzed by quantitative PCR and viability assay. Transgene expression was verified post infection with flow cytometry. Cell phenotypes were further altered with a downregulation of markers connected to MM progression (ICAM-1, CD70, CXCL10, CCL2, and sIL-2Rα) and an upregulation of the death receptor Fas. In a co-culture of immune and MM cells, LOAd viruses promoted activation of cytotoxic T cells as seen by higher CD69, CD107a, and IFNγ expression. This was most prominent with LOAd703. In conclusion, LOAd viruses are of interest for MM therapy.

The nearly neutral theory is a common framework to describe natural selection at the molecular level. This theory emphasizes the importance of slightly deleterious mutations by recognizing their ability to segregate and eventually get fixed due to genetic drift in spite of the presence of purifying selection. As genetic drift is stronger in smaller than in larger populations, a correlation between population size and molecular measures of natural selection is expected within the nearly neutral theory. However, this hypothesis was originally formulated under equilibrium conditions. As most natural populations are not in equilibrium, testing the relationship empirically may lead to confounded outcomes. Demographic nonequilibria, for instance following a change in population size, are common scenarios that are expected to push the selection-drift relationship off equilibrium. By explicitly modeling the effects of a change in population size on allele frequency trajectories in the Poisson random field framework, we obtain analytical solutions of the nonstationary allele frequency spectrum. This enables us to derive exact results of measures of natural selection and effective population size in a demographic nonequilibrium. The study of their time-dependent relationship reveals a substantial deviation from the equilibrium selection-drift balance after a change in population size. Moreover, we show that the deviation is sensitive to the combination of different measures. These results therefore constitute relevant tools for empirical studies to choose suitable measures for investigating the selection-drift relationship in natural populations. Additionally, our new modeling approach extends existing population genetics theory and can serve as foundation for methodological developments.

We introduce a multi-allele Wright-Fisher model with mutation and selection such that allele frequencies at a single locus are traced by the path of a hybrid jump-diffusion process. The state space of the process is given by the vertices and edges of a topological graph, i.e. edges are unit intervals. Vertices represent monomorphic population states and positions on the edges mark the biallelic proportions of ancestral and derived alleles during polymorphic segments. In this setting, mutations can only occur at monomorphic loci. We derive the stationary distribution in mutation-selection-drift equilibrium and obtain the expected allele frequency spectrum under large population size scaling. For the extended model with multiple independent loci we derive rigorous upper bounds for a wide class of associated measures of genetic variation. Within this framework we present mathematically precise arguments to conclude that the presence of directional selection reduces the magnitude of genetic variation, as constrained by the bounds for neutral evolution.