Quantifying the Representation of Black Adolescents in Suicide Intervention Research.

This systematic review aimed to quantify the representation of Black youth in U.S. suicide intervention research. Specifically, we sought to evaluate Black youth representation in terms of (a) equity of inclusion (i.e., the inclusion of Black youth in research study samples at a rate consistent with the overall national rate of Black adolescents in the US) and (b) equity of intervention efficacy (i.e., evaluating the presence of racial disparities in intervention efficacy/effect sizes). In addition, we aimed to evaluate whether an association existed between funding status of research and representation of Black youth in studies, and to provide recommendations for future research in this area. To this end, the present study extracted and analyzed demographic information of studies included in recent meta-analyses conducted by Robinson and colleagues (2018), which were not previously analyzed, in addition to new literature published between September 2017 and January 2021. Results showed that the prevalence of Black youth included in studies was representative (14.67%; ntotal = 4451, nBlack = 664), with a median inclusion rate of 13%; however, absolute sample and group sizes were so small that it precluded comparison of differential treatment outcomes for Black youth. Thus, out of 22 studies identified, only one was able to investigate treatment outcomes for suicide in Black youth specifically. This study points to the conclusion that without adequately powered studies, disparities in treatment efficacy for Black youth cannot be compared or addressed, and the existing disparity in suicidal outcomes for Black youth will grow even larger.

Human Fis1 directly interacts with Drp1 in an evolutionarily conserved manner to promote mitochondrial fission.

Mitochondrial fission protein 1 (Fis1) and dynamin-related protein 1 (Drp1) are the only two proteins evolutionarily conserved for mitochondrial fission, and directly interact in Saccharomyces cerevisiae to facilitate membrane scission. However, it remains unclear if a direct interaction is conserved in higher eukaryotes as other Drp1 recruiters, not present in yeast, are known. Using NMR, differential scanning fluorimetry, and microscale thermophoresis, we determined that human Fis1 directly interacts with human Drp1 (KD = 12-68 µM), and appears to prevent Drp1 assembly, but not GTP hydrolysis. Similar to yeast, the Fis1-Drp1 interaction appears governed by two structural features of Fis1: its N-terminal arm and a conserved surface. Alanine scanning mutagenesis of the arm identified both loss-of-function and gain-of-function alleles with mitochondrial morphologies ranging from highly elongated (N6A) to highly fragmented (E7A), demonstrating a profound ability of Fis1 to govern morphology in human cells. An integrated analysis identified a conserved Fis1 residue, Y76, that upon substitution to alanine, but not phenylalanine, also caused highly fragmented mitochondria. The similar phenotypic effects of the E7A and Y76A substitutions, along with NMR data, support that intramolecular interactions occur between the arm and a conserved surface on Fis1 to promote Drp1-mediated fission as in S. cerevisiae. These findings indicate that some aspects of Drp1-mediated fission in humans derive from direct Fis1-Drp1 interactions that are conserved across eukaryotes.

Fragment-based screening by protein-detected NMR spectroscopy.

Fragment-based drug discovery (FBDD) identifies low molecular weight compounds that can be developed into ligands with high affinity and selectivity for therapeutic targets. Screening fragment libraries (<10,000 molecules) with biophysical techniques against macromolecules provides information about novel chemical spaces that bind the macromolecule and scaffolds that can be modified to increase potency. A fragment-screening pipeline requires a standardized protocol for target selection, library assembly and maintenance, library screening, and hit validation to ensure hit integrity. Herein, the fundamental aspects of a fragment screening pipeline-focusing on protein-detected NMR data collection and analysis-are discussed in detail for researchers to use as a resource in their FBDD projects. Selected screening targets must undergo rigorous stability and buffer testing by NMR spectroscopy to ensure the protein structure is stable for the entire screen. Biophysical instrumentation that rapidly measures protein thermostability is helpful in buffer screening. Molecules in fragment libraries are analyzed computationally and physically, stored at appropriate temperatures, and multiplexed in well plates for library conservation. The screening protocol is streamlined using liquid handling robotics for sample preparation and customized Python scripts for protein-detected NMR data analysis. Molecules identified from the screen are titrated to determine their binding site(s) and Kd values and confirmed with an orthogonal biophysical assay. This detailed FBDD screening pipeline developed by the Program in Chemical Biology at the Medical College of Wisconsin has successfully screened many unrelated target proteins to identified novel molecules that selectively bind to these target proteins.

Cold indoor temperatures and their association with health and well-being: a systematic literature review.

OBJECTIVE: The study aimed to identify, appraise and update evidence on the association between cold temperatures (i.e. <18°C) within homes (i.e. dwellings) and health and well-being outcomes. STUDY DESIGN: This study was a systematic review. METHODS: Seven databases (MEDLINE, Embase, Cochrane Database of Systematic Reviews, CINAHL, APA PsycInfo, Applied Social Sciences Index and Abstracts, Coronavirus Research Database) were searched for studies published between 2014 and 2022, which explored the association between cold indoor temperatures and health and well-being outcomes. Studies were limited to those conducted in temperate and colder climates due to the increased risk of morbidity and mortality during winter in those climatic zones. Studies were independently quality assessed using the Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. RESULTS: Of 1209 studies, 20 were included for review. Study outcomes included cardiovascular (blood pressure, electrocardiogram abnormalities, blood platelet count), respiratory (chronic obstructive pulmonary disease symptoms, respiratory viral infection), sleep, physical performance and general health. Seventeen studies found exposure to cold indoor temperatures was associated with negative effects on health outcomes studied. Older individuals and those with chronic health problems were found to be more vulnerable to negative health outcomes. CONCLUSION: Evidence suggests that indoor temperatures <18°C are associated with negative health effects. However, the evidence is insufficient to allow clear conclusions regarding outcomes from specific temperature thresholds for different population groups. Significant gaps in the current evidence base are identified, including research on the impacts of cold indoor temperatures on mental health and well-being, studies involving young children, and the long-term health effects of cold indoor temperatures.

A conserved, noncanonical insert in FIS1 mediates TBC1D15 and DRP1 recruitment for mitochondrial fission.

Mitochondrial fission protein 1 (FIS1) is conserved in all eukaryotes, yet its function in metazoans is thought divergent. Structure-based sequence alignments of FIS1 revealed a conserved, but noncanonical, three-residue insert in its first tetratricopeptide repeat (TPR) suggesting a conserved function. In vertebrates, this insert is serine (S45), lysine (K46), and tyrosine (Y47). To determine the biological role of the "SKY insert," three variants were tested in HCT116 cells for altered mitochondrial morphology and recruitment of fission mechanoenzyme DRP1 and mitophagic adaptor TBC1D15. Similar to ectopically expressed wildtype FIS1, substitution of the SKY insert with alanine (AAA) fragmented mitochondria into perinuclear clumps associated with increased mitochondrial DRP1. In contrast, deletion variants (either ∆SKY or ∆SKYD49G) elongated mitochondrial networks with reduced mitochondrial recruitment of DRP1, despite DRP1 coimmunoprecipitates being highly enriched with ΔSKY variants. Ectopic wildtype FIS1 drove co-expressed YFP-TBC1D15 entirely from the cytoplasm to mitochondria as punctate structures concomitant with enhanced mitochondrial DRP1 recruitment. YFP-TBC1D15 co-expressed with the AAA variant further enhanced mitochondrial DRP1 recruitment, indicating a gain of function. In contrast, YFP-TBC1D15 co-expressed with deletion variants impaired mitochondrial DRP1 and YFP-TBC1D15 recruitment; however, mitochondrial fragmentation was restored. These phenotypes were not due to misfolding or poor expression of FIS1 variants, although ∆SKYD49G induced conformational heterogeneity that is lost upon deletion of the regulatory Fis1 arm, indicating SKY-arm interactions. Collectively, these results support a unifying model whereby FIS1 activity is effectively governed by intramolecular interactions between its regulatory arm and a noncanonical TPR insert that is conserved across eukaryotes.

The variable domain from dynamin-related protein 1 promotes liquid-liquid phase separation that enhances its interaction with cardiolipin-containing membranes.

Dynamins are an essential superfamily of mechanoenzymes that remodel membranes and often contain a "variable domain" important for regulation. For the mitochondrial fission dynamin, dynamin-related protein 1, a regulatory role for the variable domain (VD) is demonstrated by gain- and loss-of-function mutations, yet the basis for this is unclear. Here, the isolated VD is shown to be intrinsically disordered and undergo a cooperative transition in the stabilizing osmolyte trimethylamine N-oxide. However, the osmolyte-induced state is not folded and surprisingly appears as a condensed state. Other co-solutes including known molecular crowder Ficoll PM 70, also induce a condensed state. Fluorescence recovery after photobleaching experiments reveal this state to be liquid-like indicating the VD undergoes a liquid-liquid phase separation under crowding conditions. These crowding conditions also enhance binding to cardiolipin, a mitochondrial lipid, which appears to promote phase separation. Since dynamin-related protein 1 is found assembled into discrete punctate structures on the mitochondrial surface, the inference from the present work is that these structures might arise from a condensed state involving the VD that may enable rapid tuning of mechanoenzyme assembly necessary for fission.

The variable domain from the mitochondrial fission mechanoenzyme Drp1 promotes liquid-liquid phase separation.

Dynamins are an essential superfamily of mechanoenzymes that remodel membranes and often contain a "variable domain" (VD) important for regulation. For the mitochondrial fission dynamin, Drp1, a regulatory role for the VD is demonstrated by mutations that can elongate, or fragment, mitochondria. How the VD encodes inhibitory and stimulatory activity is unclear. Here, isolated VD is shown to be intrinsically disordered (ID) yet undergoes a cooperative transition in the stabilizing osmolyte TMAO. However, the TMAO stabilized state is not folded and surprisingly appears as a condensed state. Other co-solutes including known molecular crowder Ficoll PM 70, also induce a condensed state. Fluorescence recovery after photobleaching experiments reveal this state to be liquid-like indicating the VD undergoes a liquid-liquid phase separation under crowding conditions. These crowding conditions also enhance binding to cardiolipin, a mitochondrial lipid, raising the possibility that phase separation may enable rapid tuning of Drp1 assembly necessary for fission.

Different Mouse Models of Nemaline Myopathy Harboring Acta1 Mutations Display Differing Abnormalities Related to Mitochondrial Biology.

ACTA1 encodes skeletal muscle-specific α-actin, which polymerizes to form the thin filament of the sarcomere. Mutations in ACTA1 are responsible for approximately 30% of nemaline myopathy (NM) cases. Previous studies of weakness in NM have focused on muscle structure and contractility, but genetic issues alone do not explain the phenotypic heterogeneity observed in patients with NM or NM mouse models. To identify additional biological processes related to NM phenotypic severity, proteomic analysis was performed using muscle protein isolates from wild-type mice in comparison to moderately affected knock-in (KI) Acta1H40Y and the minimally affected transgenic (Tg) ACTA1D286G NM mice. This analysis revealed abnormalities in mitochondrial function and stress-related pathways in both mouse models, supporting an in-depth assessment of mitochondrial biology. Interestingly, evaluating each model in comparison to its wild-type counterpart identified different degrees of mitochondrial abnormality that correlated well with the phenotypic severity of the mouse model. Muscle histology, mitochondrial respiration, electron transport chain function, and mitochondrial transmembrane potential were all normal or minimally affected in the TgACTA1D286G mouse model. In contrast, the more severely affected KI.Acta1H40Y mice displayed significant abnormalities in relation to muscle histology, mitochondrial respirometry, ATP, ADP, and phosphate content, and mitochondrial transmembrane potential. These findings suggest that abnormal energy metabolism is related to symptomatic severity in NM and may constitute a contributor to phenotypic variability and a novel treatment target.

Aberrations in Energetic Metabolism and Stress-Related Pathways Contribute to Pathophysiology in the Neb Conditional Knockout Mouse Model of Nemaline Myopathy.

Nemaline myopathy (NM) is a genetically and clinically heterogeneous disease that is diagnosed on the basis of the presence of nemaline rods on skeletal muscle biopsy. Although NM has typically been classified by causative genes, disease severity or prognosis cannot be predicted. The common pathologic end point of nemaline rods (despite diverse genetic causes) and an unexplained range of muscle weakness suggest that shared secondary processes contribute to the pathogenesis of NM. We speculated that these processes could be identified through a proteome-wide interrogation using a mouse model of severe NM in combination with pathway validation and structural/functional analyses. A proteomic analysis was performed using skeletal muscle tissue from the Neb conditional knockout mouse model compared with its wild-type counterpart to identify pathophysiologically relevant biological processes that might impact disease severity or provide new treatment targets. A differential expression analysis and Ingenuity Pathway Core Analysis predicted perturbations in several cellular processes, including mitochondrial dysfunction and changes in energetic metabolism and stress-related pathways. Subsequent structural and functional studies demonstrated abnormal mitochondrial distribution, decreased mitochondrial respiratory function, an increase in mitochondrial transmembrane potential, and extremely low ATP content in Neb conditional knockout muscles relative to wild type. Overall, the findings of these studies support a role for severe mitochondrial dysfunction as a novel contributor to muscle weakness in NM.

Human Fis1 directly interacts with Drp1 in an evolutionarily conserved manner to promote mitochondrial fission.

Mitochondrial Fission Protein 1 (Fis1) and Dynamin Related Protein 1 (Drp1) are the only two proteins evolutionarily conserved for mitochondrial fission, and directly interact in S. cerevisiae to facilitate membrane scission. However, it remains unclear if a direct interaction is conserved in higher eukaryotes as other Drp1 recruiters, not present in yeast, are known. Using NMR, differential scanning fluorimetry, and microscale thermophoresis, we determined that human Fis1 directly interacts with human Drp1 ( K D = 12-68 µM), and appears to prevent Drp1 assembly, but not GTP hydrolysis. Similar to yeast, the Fis1-Drp1 interaction appears governed by two structural features of Fis1: its N-terminal arm and a conserved surface. Alanine scanning mutagenesis of the arm identified both loss- and gain-of-function alleles with mitochondrial morphologies ranging from highly elongated (N6A) to highly fragmented (E7A) demonstrating a profound ability of Fis1 to govern morphology in human cells. An integrated analysis identified a conserved Fis1 residue, Y76, that upon substitution to alanine, but not phenylalanine, also caused highly fragmented mitochondria. The similar phenotypic effects of the E7A and Y76A substitutions, along with NMR data, support that intramolecular interactions occur between the arm and a conserved surface on Fis1 to promote Drp1-mediated fission as in S. cerevisiae . These findings indicate that some aspects of Drp1-mediated fission in humans derive from direct Fis1-Drp1 interactions that are conserved across eukaryotes.

14-3-3 and Smad2/3 are crucial mediators of atypical-PKCs: Implications for neuroblastoma progression.

Neuroblastoma (NB) is a cancer that develops in the neuroblasts. It is the most common cancer in children under the age of 1 year, accounting for approximately 6% of all cancers. The prognosis of NB is linked to both age and degree of cell differentiation. This results in a range of survival rates for patients, with outcomes ranging from recurrence and mortality to high survival rates and tumor regression. Our previous work indicated that PKC-ι promotes cell proliferation in NB cells through the PKC-ι/Cdk7/Cdk2 cascade. We report on two atypical protein kinase inhibitors as potential therapeutic candidates against BE(2)-C and BE(2)-M17 cells: a PKC-ι-specific 5-amino-1-2,3-dihydroxy-4-(methylcyclopentyl)-1H-imidazole-4-carboxamide and a PKC-ζ specific 8-hydroxy-1,3,6-naphthalenetrisulfonic acid. Both compounds induced apoptosis and retarded the epithelial-mesenchymal transition (EMT) of NB cells. Proteins 14-3-3 and Smad2/3 acted as central regulators of aPKC-driven progression in BE(2)-C and BE(2)-M17 cells in relation to the Akt1/NF-κB and TGF-ß pathways. Data indicates that aPKCs upregulate Akt1/NF-κB and TGF-ß pathways in NB cells through an association with 14-3-3 and Smad2/3 that can be diminished by aPKC inhibitors. In summary, both inhibitors appear to be promising potential neuroblastoma therapeutics and merit further research.

Complex organisational factors influence multidisciplinary care for patients with hip fractures: a qualitative study of barriers and facilitators to service delivery.

BACKGROUND: Hip fractures are devastating injuries, with high health and social care costs. Despite national standards and guidelines, substantial variation persists in hospital delivery of hip fracture care and patient outcomes. This qualitative study aimed to identify organisational processes that can be targeted to reduce variation in service provision and improve patient care. METHODS: Interviews were conducted with 40 staff delivering hip fracture care in four UK hospitals. Twenty-three anonymised British Orthopaedic Association reports addressing under-performing hip fracture services were analysed. Following Thematic Analysis of both data sources, themes were transposed onto domains both along and across the hip fracture care pathway. RESULTS: Effective pre-operative care required early alert of patient admission and the availability of staff in emergency departments to undertake assessments, investigations and administer analgesia. Coordinated decision-making between medical and surgical teams regarding surgery was key, with strategies to ensure flexible but efficient trauma lists. Orthogeriatric services were central to effective service delivery, with collaborative working and supervision of junior doctors, specialist nurses and therapists. Information sharing via multidisciplinary meetings was facilitated by joined up information and technology systems. Service provision was improved by embedding hip fracture pathway documents in induction and training and ensuring their consistent use by the whole team. Hospital executive leadership was important in prioritising hip fracture care and advocating service improvement. Nominated specialty leads, who jointly owned the pathway and met regularly, actively steered services and regularly monitored performance, investigating lapses and consistently feeding back to the multidisciplinary team. CONCLUSION: Findings highlight the importance of representation from all teams and departments involved in the multidisciplinary care pathway, to deliver integrated hip fracture care. Complex, potentially modifiable, barriers and facilitators to care delivery were identified, informing recommendations to improve effective hip fracture care delivery, and assist hospital services when re-designing and implementing service improvements.

Loss of non-motor kinesin KIF26A causes congenital brain malformations via dysregulated neuronal migration and axonal growth as well as apoptosis.

Kinesins are canonical molecular motors but can also function as modulators of intracellular signaling. KIF26A, an unconventional kinesin that lacks motor activity, inhibits growth-factor-receptor-bound protein 2 (GRB2)- and focal adhesion kinase (FAK)-dependent signal transduction, but its functions in the brain have not been characterized. We report a patient cohort with biallelic loss-of-function variants in KIF26A, exhibiting a spectrum of congenital brain malformations. In the developing brain, KIF26A is preferentially expressed during early- and mid-gestation in excitatory neurons. Combining mice and human iPSC-derived organoid models, we discovered that loss of KIF26A causes excitatory neuron-specific defects in radial migration, localization, dendritic and axonal growth, and apoptosis, offering a convincing explanation of the disease etiology in patients. Single-cell RNA sequencing in KIF26A knockout organoids revealed transcriptional changes in MAPK, MYC, and E2F pathways. Our findings illustrate the pathogenesis of KIF26A loss-of-function variants and identify the surprising versatility of this non-motor kinesin.

Structural studies of human fission protein FIS1 reveal a dynamic region important for GTPase DRP1 recruitment and mitochondrial fission.

Fission protein 1 (FIS1) and dynamin-related protein 1 (DRP1) were initially described as being evolutionarily conserved for mitochondrial fission, yet in humans the role of FIS1 in this process is unclear and disputed by many. In budding yeast where Fis1p helps to recruit the DRP1 ortholog from the cytoplasm to mitochondria for fission, an N-terminal "arm" of Fis1p is required for function. The yeast Fis1p arm interacts intramolecularly with a conserved tetratricopeptide repeat core and governs in vitro interactions with yeast DRP1. In human FIS1, NMR and X-ray structures show different arm conformations, but its importance for human DRP1 recruitment is unknown. Here, we use molecular dynamics simulations and comparisons to experimental NMR chemical shifts to show the human FIS1 arm can adopt an intramolecular conformation akin to that observed with yeast Fis1p. This finding is further supported through intrinsic tryptophan fluorescence and NMR experiments on human FIS1 with and without the arm. Using NMR, we observed the human FIS1 arm is also sensitive to environmental changes. We reveal the importance of these findings in cellular studies where removal of the FIS1 arm reduces DRP1 recruitment and mitochondrial fission similar to the yeast system. Moreover, we determined that expression of mitophagy adapter TBC1D15 can partially rescue arm-less FIS1 in a manner reminiscent of expression of the adapter Mdv1p in yeast. These findings point to conserved features of FIS1 important for its activity in mitochondrial morphology. More generally, other tetratricopeptide repeat-containing proteins are flanked by disordered arms/tails, suggesting possible common regulatory mechanisms.

Fusarium and allied fusarioid taxa (FUSA). 1.

Seven Fusarium species complexes are treated, namely F. aywerte species complex (FASC) (two species), F. buharicum species complex (FBSC) (five species), F. burgessii species complex (FBURSC) (three species), F. camptoceras species complex (FCAMSC) (three species), F. chlamydosporum species complex (FCSC) (eight species), F. citricola species complex (FCCSC) (five species) and the F. concolor species complex (FCOSC) (four species). New species include Fusicolla elongata from soil (Zimbabwe), and Neocosmospora geoasparagicola from soil associated with Asparagus officinalis (Netherlands). New combinations include Neocosmospora akasia, N. awan, N. drepaniformis, N. duplosperma, N. geoasparagicola, N. mekan, N. papillata, N. variasi and N. warna. Newly validated taxa include Longinectria gen. nov., L. lagenoides, L. verticilliforme, Fusicolla gigas and Fusicolla guangxiensis. Furthermore, Fusarium rosicola is reduced to synonymy under N. brevis. Finally, the genome assemblies of Fusarium secorum (CBS 175.32), Microcera coccophila (CBS 310.34), Rectifusarium robinianum (CBS 430.91), Rugonectria rugulosa (CBS 126565), and Thelonectria blattea (CBS 952.68) are also announced here. Citation: Crous PW, Sandoval-Denis M, Costa MM, Groenewald JZ, van Iperen AL, Starink-Willemse M, Hernández-Restrepo M, Kandemir H, Ulaszewski B, de Boer W, Abdel-Azeem AM, Abdollahzadeh J, Akulov A, Bakhshi M, Bezerra JDP, Bhunjun CS, Câmara MPS, Chaverri P, Vieira WAS, Decock CA, Gaya E, Gené J, Guarro J, Gramaje D, Grube M, Gupta VK, Guarnaccia V, Hill R, Hirooka Y, Hyde KD, Jayawardena RS, Jeewon R, Jurjevic Z, Korsten L, Lamprecht SC, Lombard L, Maharachchikumbura SSN, Polizzi G, Rajeshkumar KC, Salgado-Salazar C, Shang Q-J, Shivas RG, Summerbell RC, Sun GY, Swart WJ, Tan YP, Vizzini A, Xia JW, Zare R, González CD, Iturriaga T, Savary O, Coton M, Coton E, Jany J-L, Liu C, Zeng Z-Q, Zhuang W-Y, Yu Z-H, Thines M (2022). Fusarium and allied fusarioid taxa (FUSA). 1. Fungal Systematics and Evolution 9: 161-200. doi: 10.3114/fuse.2022.09.08.

Development of a novel intervention to improve sleep and pain in patients undergoing total knee replacement.

BACKGROUND: Up to 20% of patients experience long-term pain and dissatisfaction after total knee replacement, with a negative impact on their quality of life. New approaches are needed to reduce the proportion of people to go on to experience chronic post-surgical pain. Sleep and pain are bidirectionally linked with poor sleep linked to greater pain. Interventions to improve sleep among people undergoing knee replacement offer a promising avenue. Health beliefs and barriers to engagement were explored using behaviour change theory. This study followed stages 1-4 of the Medical Research Council's guidance for complex intervention development to develop a novel intervention aimed at improving sleep in pre-operative knee replacement patients. METHODS: Pre-operative focus groups and post-operative telephone interviews were conducted with knee replacement patients. Before surgery, focus groups explored sleep experiences and views about existing sleep interventions (cognitive behavioural therapy for insomnia, exercise, relaxation, mindfulness, sleep hygiene) and barriers to engagement. After surgery, telephone interviews explored any changes in sleep and views about intervention appropriateness. Data were audio-recorded, transcribed, anonymised, and analysed using framework analysis. RESULTS: Overall, 23 patients took part, 17 patients attended pre-operative focus groups, seven took part in a post-operative telephone interview, and one took part in a focus group and interview. Key sleep issues identified were problems getting to sleep, frequent waking during the night, and problems getting back to sleep after night waking. The main reason for these issues was knee pain and discomfort and a busy mind. Participants felt that the sleep interventions were generally acceptable with no general preference for one intervention over the others. Views of delivery mode varied in relation to digital move and group or one-to-one approaches. CONCLUSION: Existing sleep interventions were found to be acceptable to knee replacement patients. Key barriers to engagement related to participants' health beliefs. Addressing beliefs about the relationship between sleep and pain and enhancing understanding of the bidirectional/cyclical relationship could benefit engagement and motivation. Individuals may also require support to break the fear and avoidance cycle of pain and coping. A future intervention should ensure that patients' preferences for sleep interventions and delivery mode can be accommodated in a real-world context.

Novel <i>DNM1L</i> variants impair mitochondrial dynamics through divergent mechanisms.

Imbalances in mitochondrial and peroxisomal dynamics are associated with a spectrum of human neurological disorders. Mitochondrial and peroxisomal fission both involve dynamin-related protein 1 (DRP1) oligomerisation and membrane constriction, although the precise biophysical mechanisms by which distinct DRP1 variants affect the assembly and activity of different DRP1 domains remains largely unexplored. We analysed four unreported de novo heterozygous variants in the dynamin-1-like gene <i>DNM1L</i>, affecting different highly conserved DRP1 domains, leading to developmental delay, seizures, hypotonia, and/or rare cardiac complications in infancy. Single-nucleotide DRP1 stalk domain variants were found to correlate with more severe clinical phenotypes, with in vitro recombinant human DRP1 mutants demonstrating greater impairments in protein oligomerisation, DRP1-peroxisomal recruitment, and both mitochondrial and peroxisomal hyperfusion compared to GTPase or GTPase-effector domain variants. Importantly, we identified a novel mechanism of pathogenesis, where a p.Arg710Gly variant uncouples DRP1 assembly from assembly-stimulated GTP hydrolysis, providing mechanistic insight into how assembly-state information is transmitted to the GTPase domain. Together, these data reveal that discrete, pathological <i>DNM1L</i> variants impair mitochondrial network maintenance by divergent mechanisms.

The effect of capromorelin on glycemic control in healthy dogs.

Capromorelin is a ghrelin-receptor agonist widely used as an appetite stimulant in dogs. Capromorelin disrupts glucose homeostasis in cats but information regarding its effects on canine glucose homeostasis is lacking. The study objective was to evaluate the effect of capromorelin on glucose homeostatic mechanisms in healthy dogs. Eight clinically healthy client-owned adult dogs were enrolled in this prospective, cross-over, placebo-controlled study. Dogs were randomized to receive capromorelin (Entyce, 3 mg/kg) or placebo, q24h for 3 d. A wk later, treatments were crossed over. Interstitial glucose (IG) concentrations were measured using a flash glucose monitoring system throughout. On d 1 of each treatment, blood glucose (BG), insulin, glucagon, glucose-dependent insulinotropic peptide (GIP), and glucagon-like peptide-1 (GLP-1) concentrations were measured before drug administration, then before and 30-120 min after feeding a glucose-rich diet (Ensure Plus, 21 kcal/kg). Data were analyzed as a 2-period crossover design using generalized least squares estimation. Capromorelin administration increased mean 48 h IG by10% and mean BG by 20% at 90 and 120 min post-prandially (P < 0.0001). Post-prandially, there was a time-by-treatment effect for insulin (P = 0.03) and GIP (P = 0.0002) because capromorelin doubled geometric mean insulin concentrations at 120 min and increased geometric mean GIP concentrations more rapidly than after placebo. There were no differences in glucagon or GLP-1 concentrations between treatment groups. The increase in post-prandial blood glucose was not the result of overt suppression of incretin hormone secretion. There was also no suppressive effect of capromorelin on insulin.

Kidney morphology in pregnancy using T2-weighted MRI.

AIM: To report the morphology of maternal kidneys captured on fetal magnetic resonance imaging (MRI) including kidney length, volume, renal pelvis diameter, and corticomedullary differentiation in pregnancy. MATERIALS AND METHODS: A retrospective study of maternal kidney morphology captured incidentally on fetal MRI. Women without chronic kidney disease, with a complete view of both kidneys and a singleton pregnancy were included. Kidney length, maximal renal pelvis diameter, kidney volume, and corticomedullary differentiation ratio were measured independently in duplicate. Associations with maternal and pregnancy variables were explored using linear regression. RESULTS: MRI images from 42 women were performed at 22-32 weeks' gestation. Serum creatinine concentrations are not checked routinely during pregnancy and were available for 15 (36%) women, with a median creatinine of 57 µmol/l (IQR: 50-63 µmol/l). Mean interpolar lengths were 10.9 and 10.4 cm for the left and right kidneys and varied with height. Mean maximal renal pelvis diameters were 9 mm and 12 mm, with upper reference intervals of 17 and 25 mm for the left and right kidneys, respectively. Renal volume in pregnancy was within the non-pregnant reference interval and varied with height and gestation. CONCLUSIONS: Maternal kidney length and volume in pregnancy are within the normal reference intervals for non-pregnant women. Renal pelvis diameter in pregnancy measured using MRI is substantially higher than described previously by ultrasound, with implications for routine reporting.

Use of calculations to validate beam quality and relative dose measurements for a kilovoltage X-ray therapy unit.

Relative dosimetry measurements are required to fully commission kilovoltage X-ray units for superficial and orthovoltage X-ray therapy. Validation of these relative dosimetry measurements with Monte Carlo methods is advantageous being independent of the measurement process. In this study use is made of the X-ray spectrum generating program SpekPy along with the EGSnrc Monte Carlo code to calculate depth doses and explore the dosimetry effect of changes in backscatter. These calculations are compared with previously reported measurements for the Pantak SXT 150 X-ray therapy unit. SpekPy can also be used to generate half value layer (HVL) values and these are also compared to previously reported HVL measurements for the same X-ray therapy unit. It was found that agreements of the order of 5% in HVL, 3% in depth dose and 1% in backscatter doses were found between Monte Carlo calculations and the previously published measured data. Exit doses in conditions of lack of full backscatter were explored with Monte Carlo calculations demonstrating reduced exit dose up to 20% in these conditions. It is concluded that SpekPy with Monte Carlo codes such as EGSnrc provides a straightforward approach to validating various relative dosimetry measurements in kilovoltage X-ray dosimetry.