Enhanced triple-α reaction reduces proton-rich nucleosynthesis in supernovae.

The rate of the triple-α reaction that forms 12C affects1,2 the synthesis of heavy elements in the Ga-Cd range in proton-rich neutrino-driven outflows of core-collapse supernovae3-5. Initially, these outflows contain only protons and neutrons; these later combine to form α particles, then 12C nuclei via the triple-α reaction, and eventually heavier nuclei as the material expands and cools. Previous experimental work6,7 demonstrated that despite the high temperatures encountered in these environments, the reaction is dominated by the well characterized Hoyle state resonance in 12C nuclei. At sufficiently high nucleon densities, however, proton- and neutron-scattering processes may alter the effective width of the Hoyle state8,9. This raises the questions of what the reaction rate in supernova outflows is, and how changes affect nucleosynthesis predictions. Here we report that in proton-rich core-collapse supernova outflows, these hitherto neglected processes enhance the triple-α reaction rate by up to an order of magnitude. The larger reaction rate suppresses the production of heavy proton-rich isotopes that are formed by the νp process3-5 (where ν is the neutrino and p is the proton) in the innermost ejected material of supernovae10-13. Previous work on the rate enhancement mechanism9 did not anticipate the importance of this enhancement for proton-rich nucleosynthesis. Because the in-medium contribution to the triple-α reaction rate must be present at high densities, this effect needs to be included in supernova nucleosynthesis models. This enhancement also differs from earlier sensitivity studies that explored variations of the unenhanced rate by a constant factor1,2, because the enhancement depends on the evolving thermodynamic conditions. The resulting suppression of heavy-element nucleosynthesis for realistic conditions casts doubt on the νp process being the explanation for the anomalously high abundances of 92,94Mo and 96,98Ru isotopes in the Solar System1,3,14 and for the signatures of early Universe element synthesis in the Ga-Cd range found in the spectra of ancient metal-poor stars15-20.

The 5:2 diet does not increase adult hippocampal neurogenesis or enhance spatial memory in mice.

New neurones are generated throughout life in the mammalian brain in a process known as adult hippocampal neurogenesis (AHN). Since this phenomenon grants a high degree of neuroplasticity influencing learning and memory, identifying factors that regulate AHN may be important for ameliorating age-related cognitive decline. Calorie restriction (CR) has been shown to enhance AHN and improve memory, mediated by the stomach hormone, ghrelin. Intermittent fasting (IF), a dietary strategy offering more flexibility than conventional CR, has also been shown to promote aspects of AHN. The 5:2 diet is a popular form of IF; however, its effects on AHN are not well characterised. To address this, we quantified AHN in adolescent and adult wild-type and ghrelin-receptor-deficient mice following 6 weeks on a 5:2 diet. We report an age-related decline in neurogenic processes. However, the 5:2 diet does not increase AHN nor enhance memory performance, suggesting that this specific form of IF is ineffective in promoting brain plasticity to support learning.

A population of naive-like CD4+ T cells stably polarized to the TH 1 lineage.

T-bet is the lineage-specifying transcription factor for CD4+ TH 1 cells. T-bet has also been found in other CD4+ T cell subsets, including TH 17 cells and Treg, where it modulates their functional characteristics. However, we lack information on when and where T-bet is expressed during T cell differentiation and how this impacts T cell differentiation and function. To address this, we traced the ontogeny of T-bet-expressing cells using a fluorescent fate-mapping mouse line. We demonstrate that T-bet is expressed in a subset of CD4+ T cells that have naïve cell surface markers and transcriptional profile and that this novel cell population is phenotypically and functionally distinct from previously described populations of naïve and memory CD4+ T cells. Naïve-like T-bet-experienced cells are polarized to the TH 1 lineage, predisposed to produce IFN-γ upon cell activation, and resist repolarization to other lineages in vitro and in vivo. These results demonstrate that lineage-specifying factors can polarize T cells in the absence of canonical markers of T cell activation and that this has an impact on the subsequent T-helper response.

Acyl-Ghrelin Attenuates Neurochemical and Motor Deficits in the 6-OHDA Model of Parkinson's Disease.

The feeding-related hormone, acyl-ghrelin, protects dopamine neurones in murine 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-based models of experimental Parkinson's disease (PD). However, the potential protective effect of acyl-ghrelin on substantia nigra pars compacta (SNpc) dopaminergic neurones and consequent behavioural correlates in the more widely used 6-hydroxydopamine (6-OHDA) rat medial forebrain bundle (MFB) lesion model of PD are unknown. To address this question, acyl-ghrelin levels were raised directly by mini-pump infusion for 7 days prior to unilateral injection of 6-OHDA into the MFB with assessment of amphetamine-induced rotations on days 27 and 35, and immunohistochemical analysis of dopaminergic neurone survival. Whilst acyl-ghrelin treatment was insufficient to elevate food intake or body weight, it attenuated amphetamine-induced circling behaviour and SNpc dopamine neurone loss induced by 6-OHDA. These data support the notion that elevating circulating acyl-ghrelin may be a valuable approach to slow or impair progression of neurone loss in PD.

MicroRNA-142 Critically Regulates Group 2 Innate Lymphoid Cell Homeostasis and Function.

Innate lymphoid cells are central to the regulation of immunity at mucosal barrier sites, with group 2 innate lymphoid cells (ILC2s) being particularly important in type 2 immunity. In this study, we demonstrate that microRNA(miR)-142 plays a critical, cell-intrinsic role in the homeostasis and function of ILC2s. Mice deficient for miR-142 expression demonstrate an ILC2 progenitor-biased development in the bone marrow, and along with peripheral ILC2s at mucosal sites, these cells display a greatly altered phenotype based on surface marker expression. ILC2 proliferative and effector functions are severely dysfunctional following Nippostrongylus brasiliensis infection, revealing a critical role for miR-142 isoforms in ILC2-mediated immune responses. Mechanistically, Socs1 and Gfi1 expression are regulated by miR-142 isoforms in ILC2s, impacting ILC2 phenotypes as well as the proliferative and effector capacity of these cells. The identification of these novel pathways opens potential new avenues to modulate ILC2-dependent immune functions.

Effects of canagliflozin versus finerenone on cardiorenal outcomes: exploratory post hoc analyses from FIDELIO-DKD compared to reported CREDENCE results.

BACKGROUND: The nonsteroidal mineralocorticoid receptor antagonist finerenone and the sodium-glucose cotransporter-2 inhibitor (SGLT-2i) canagliflozin reduce cardiorenal risk in albuminuric patients with chronic kidney disease (CKD) and type 2 diabetes (T2D). At first glance, the results of Finerenone in Reducing Kidney Failure and Disease Progression in Diabetic Kidney Disease (FIDELIO-DKD) (ClinicalTrials.gov, NCT02540993) and Canagliflozin and Renal Events in Diabetes with Established Nephropathy Clinical Evaluation (CREDENCE) appear disparate. In FIDELIO-DKD, the primary endpoint had an 18% [95% confidence interval (CI) 7-27] relative risk reduction; in CREDENCE, the primary endpoint had a 30% (95% CI 18-41) relative risk reduction. Unlike CREDENCE, the FIDELIO-DKD trial included patients with high albuminuria but excluded patients with symptomatic heart failure with reduced ejection fraction. The primary endpoint in the FIDELIO-DKD trial was kidney specific and included a sustained decline in the estimated glomerular filtration rate (eGFR) of ≥40% from baseline. In contrast, the primary endpoint in the CREDENCE trial included a sustained decline in eGFR of ≥57% from baseline and cardiovascular (CV) death. This post hoc exploratory analysis investigated how differences in trial design-inclusion/exclusion criteria and definition of primary outcomes-influenced observed treatment effects. METHODS: Patients from FIDELIO-DKD who met the CKD inclusion criteria of the CREDENCE study (urine albumin: creatinine ratio >300-5000 mg/g and an eGFR of 30-<90 mL/min/1.73 m2 at screening) were included in this analysis. The primary endpoint was a cardiorenal composite (CV death, kidney failure, eGFR decrease of ≥57% sustained for ≥4 weeks or renal death). Patients with symptomatic heart failure with reduced ejection fraction were excluded from FIDELIO-DKD. Therefore, in a sensitivity analysis, we further adjusted for the baseline prevalence of heart failure. RESULTS: Of 4619/5674 (81.4%) patients who met the subgroup inclusion criteria, 49.6% were treated with finerenone and 50.4% received placebo. The rate of the cardiorenal composite endpoint was 43.9/1000 patient-years with finerenone compared with 59.5/1000 patient-years with placebo. The relative risk was significantly reduced by 26% with finerenone versus placebo [hazard ratio (HR) 0.74 (95% CI 0.63-0.87)]. In CREDENCE, the rate of the cardiorenal composite endpoint was 43.2/1000 patient-years with canagliflozin compared with 61.2/1000 patient-years with placebo; a 30% risk reduction was observed with canagliflozin [HR 0.70 (95% CI 0.59-0.82)]. CONCLUSIONS: This analysis highlights the pitfalls of direct comparisons between trials. When key differences in trial design are considered, FIDELIO-DKD and CREDENCE demonstrate cardiorenal benefits of a similar magnitude.

Acute pain assessments and records: a pilot study of digital transformation.

BACKGROUND: Pain is a leading cause of disability worldwide. Pain assessments are an essential part of evidence-based care and management. Among comparable care providers, there is variation in how nurses document assessments as well as the content in them, and there is a notable associated administrative burden. AIMS: This study evaluated the impact and significance of a new, structured, digitised pain assessment form from quality, safety and efficiency standpoints. METHODS: Samples of pain assessments were examined at three consecutive stages: first, the pre-existing form was used, then the new structured form was introduced and, finally, the structured form was taken away and nurses went back to completing the original form. Assessments were scored by two clinical analysts against 18 clinically defined pain-related characteristics and factors. The time taken to extract and interpret the assessments was also recorded. Statistically significant changes were assessed using Welch's t-tests and Fisher's exact tests. FINDINGS: There was a significant improvement in data quality using the new structured form compared with the pre-existing template, including an increase in the capture of five safety-related variables. Less time was needed to extract and interpret data with the new form. CONCLUSION: Intelligent structured forms are highly effective for documenting pain assessments, and offer notable benefits in quality, safety, and efficiency.

A large-scale dynamo and magnetoturbulence in rapidly rotating core-collapse supernovae.

Magnetohydrodynamic turbulence is important in many high-energy astrophysical systems, where instabilities can amplify the local magnetic field over very short timescales. Specifically, the magnetorotational instability and dynamo action have been suggested as a mechanism for the growth of magnetar-strength magnetic fields (of 10(15) gauss and above) and for powering the explosion of a rotating massive star. Such stars are candidate progenitors of type Ic-bl hypernovae, which make up all supernovae that are connected to long γ-ray bursts. The magnetorotational instability has been studied with local high-resolution shearing-box simulations in three dimensions, and with global two-dimensional simulations, but it is not known whether turbulence driven by this instability can result in the creation of a large-scale, ordered and dynamically relevant field. Here we report results from global, three-dimensional, general-relativistic magnetohydrodynamic turbulence simulations. We show that hydromagnetic turbulence in rapidly rotating protoneutron stars produces an inverse cascade of energy. We find a large-scale, ordered toroidal field that is consistent with the formation of bipolar magnetorotationally driven outflows. Our results demonstrate that rapidly rotating massive stars are plausible progenitors for both type Ic-bl supernovae and long γ-ray bursts, and provide a viable mechanism for the formation of magnetars. Moreover, our findings suggest that rapidly rotating massive stars might lie behind potentially magnetar-powered superluminous supernovae.

Dominant regulation of long-term allograft survival is mediated by microRNA-142.

Organ transplantation is often lifesaving, but the long-term deleterious effects of combinatorial immunosuppression regimens and allograft failure cause significant morbidity and mortality. Long-term graft survival in the absence of continuing immunosuppression, defined as operational tolerance, has never been described in the context of multiple major histocompatibility complex (MHC) mismatches. Here, we show that miR-142 deficiency leads to indefinite allograft survival in a fully MHC mismatched murine cardiac transplant model in the absence of exogenous immunosuppression. We demonstrate that the cause of indefinite allograft survival in the absence of miR-142 maps specifically to the T cell compartment. Of therapeutic relevance, temporal deletion of miR-142 in adult mice prior to transplantation of a fully MHC mismatched skin allograft resulted in prolonged allograft survival. Mechanistically, miR-142 directly targets Tgfbr1 for repression in regulatory T cells (TREG ). This leads to increased TREG sensitivity to transforming growth factor - beta and promotes transplant tolerance via an augmented peripheral TREG response in the absence of miR-142. These data identify manipulation of miR-142 as a promising approach for the induction of tolerance in human transplantation.

Modulation of the Immune Response by Nematode Secreted Acetylcholinesterase Revealed by Heterologous Expression in Trypanosoma musculi.

Nematode parasites secrete molecules which regulate the mammalian immune system, but their genetic intractability is a major impediment to identifying and characterising the biological effects of these molecules. We describe here a novel system for heterologous expression of helminth secreted proteins in the natural parasite of mice, Trypanosoma musculi, which can be used to analyse putative immunomodulatory functions. Trypanosomes were engineered to express a secreted acetylcholinesterase from Nippostrongylus brasiliensis. Infection of mice with transgenic parasites expressing acetylcholinesterase resulted in truncated infection, with trypanosomes cleared early from the circulation. Analysis of cellular phenotypes indicated that exposure to acetylcholinesterase in vivo promoted classical activation of macrophages (M1), with elevated production of nitric oxide and lowered arginase activity. This most likely occurred due to the altered cytokine environment, as splenocytes from mice infected with T. musculi expressing acetylcholinesterase showed enhanced production of IFNγ and TNFα, with diminished IL-4, IL-13 and IL-5. These results suggest that one of the functions of nematode secreted acetylcholinesterase may be to alter the cytokine environment in order to inhibit development of M2 macrophages which are deleterious to parasite survival. Transgenic T. musculi represents a valuable new vehicle to screen for novel immunoregulatory proteins by extracellular delivery in vivo to the murine host.

Surfactant Protein-D Is Essential for Immunity to Helminth Infection.

Pulmonary epithelial cell responses can enhance type 2 immunity and contribute to control of nematode infections. An important epithelial product is the collectin Surfactant Protein D (SP-D). We found that SP-D concentrations increased in the lung following Nippostrongylus brasiliensis infection; this increase was dependent on key components of the type 2 immune response. We carried out loss and gain of function studies of SP-D to establish if SP-D was required for optimal immunity to the parasite. N. brasiliensis infection of SP-D-/- mice resulted in profound impairment of host innate immunity and ability to resolve infection. Raising pulmonary SP-D levels prior to infection enhanced parasite expulsion and type 2 immune responses, including increased numbers of IL-13 producing type 2 innate lymphoid cells (ILC2), elevated expression of markers of alternative activation by alveolar macrophages (alvM) and increased production of the type 2 cytokines IL-4 and IL-13. Adoptive transfer of alvM from SP-D-treated parasite infected mice into naïve recipients enhanced immunity to N. brasiliensis. Protection was associated with selective binding by the SP-D carbohydrate recognition domain (CRD) to L4 parasites to enhance their killing by alvM. These findings are the first demonstration that the collectin SP-D is an essential component of host innate immunity to helminths.

Acute and chronic effects of aquatic treadmill training on land treadmill running kinematics: A cross-over and single-subject design approach.

The aim of this study was to determine if selected kinematic measures (foot strike index [SI], knee contact angle and overstride angle) were different between aquatic treadmill (ATM) and land treadmill (LTM) running, and to determine if these measures were altered during LTM running as a result of 6 weeks of ATM training. Acute effects were tested using 15 competitive distance runners who completed 1 session of running on each treadmill type at 5 different running speeds. Subsequently, three recreational runners completed 6 weeks of ATM training following a single-subject baseline, intervention and withdrawal experiment. Kinematic measures were quantified from digitisation of video. Regardless of speed, SI values during ATM running (61.3 ± 17%) were significantly greater (P = 0.002) than LTM running (42.7 ± 23%). Training on the ATM did not change (pre/post) the SI (26 ± 3.2/27 ± 3.1), knee contact angle (165 ± 0.3/164 ± 0.8) or overstride angle (89 ± 0.4/89 ± 0.1) during LTM running. Although SI values were different between acute ATM and LTM running, 6 weeks of ATM training did not appear to alter LTM running kinematics as evidenced by no change in kinematic values from baseline to post intervention assessments.

Diagnosis and treatment of a biliary fistula to walled-off pancreatic necrosis.

Video 1Visualization and treatment of a biliary fistula into a walled-off pancreatic necrosis collection.

MicroRNA-142 regulates gut associated lymphoid tissues and group 3 innate lymphoid cells.

The transcriptomic signatures that shape responses of innate lymphoid cells (ILCs) have been well characterised, however post-transcriptional mechanisms which regulate their development and activity remain poorly understood. We demonstrate that ILC groups of the intestinal lamina propria express mature forms of microRNA-142 (miR-142), an evolutionarily conserved microRNA family with several non-redundant regulatory roles within the immune system. Germline Mir142 deletion alters intestinal ILC compositions, resulting in the absence of T-bet+ populations and significant defects in the cellularity and phenotypes of ILC3 subsets including CCR6+ LTi-like ILC3s. These effects were associated with decreased pathology in an innate-immune cell driven model of colitis. Furthermore, Mir142-/- mice demonstrate defective development of gut-associated lymphoid tissues, including a complete absence of mature Peyer's patches. Conditional deletion of Mir142 in ILC3s (RorcΔMir142) supported cell-intrinsic roles for these microRNAs in establishing or maintaining cellularity and functions of LTi-like ILC3s in intestinal associated tissues. RNAseq analysis revealed several target genes and biological pathways potentially regulated by miR-142 microRNAs in these cells. Finally, lack of Mir142 in ILC3 led to elevated IL-17A production. These data broaden our understanding of immune system roles of miR-142 microRNAs, identifying these molecules as critical post-transcriptional regulators of ILC3s and intestinal mucosal immunity.

Finerenone and left ventricular hypertrophy in chronic kidney disease and type 2 diabetes.

AIMS: Left ventricular hypertrophy (LVH) has been associated with an increased risk of cardiovascular (CV) disease and linked to increased morbidity and mortality. In patients with chronic kidney disease (CKD) and type 2 diabetes (T2D), hypertension is common, and patients with these co-morbidities additionally have a high prevalence of LVH. This analysis of the prespecified pooled FIDELITY analysis comprising the randomized, double-blind, placebo-controlled, multicentre FIDELIO-DKD and FIGARO-DKD phase III studies aimed to explore the CV and kidney effects of finerenone, a nonsteroidal mineralocorticoid receptor antagonist, in patients with CKD and T2D stratified by a diagnosis of LVH at baseline. METHODS AND RESULTS: A diagnosis of LVH in the FIDELITY patient population was determined at baseline using investigator-reported electrocardiogram (ECG) findings. The two efficacy outcomes, assessed by baseline LVH, were the composite CV outcome of time to CV death, non-fatal myocardial infarction, non-fatal stroke, or hospitalization for heart failure (HHF), and a composite kidney outcome of time to onset of kidney failure, a sustained decrease in estimated glomerular filtration rate (eGFR) ≥57% from baseline over ≥4 weeks, or kidney-related death. Safety outcomes by baseline LVH were reported as treatment-emergent adverse events. At baseline out of 13 026 patients in FIDELITY, 96.5% had hypertension and 9.6% had investigator-reported LVH. The relative risk reduction for the composite CV and kidney outcomes with finerenone versus placebo was lower in the LVH subgroup; however, the treatment effect of finerenone was not modified by baseline LVH for either outcome (Pinteraction = 0.1075 for composite CV outcome and Pinteraction = 0.1782 for composite kidney outcome). Analysis of the composite CV outcome components showed a greater reduction in the risk of HHF versus placebo for patients with baseline LVH compared with those without (Pinteraction = 0.0024). Overall safety events were comparable between the LVH subgroups and treatment arms. Treatment-emergent hyperkalaemia was observed more frequently with finerenone versus placebo, but discontinuation rates were low in both treatment arms and between LVH subgroups. CONCLUSIONS: In conclusion, the overall CV and kidney benefits of finerenone versus placebo were not modified by the presence of LVH at baseline, with overall safety findings being similar between LVH subgroups. A greater benefit was observed for HHF in patients with versus without LVH, suggesting that LVH may be a predictor of the treatment effect of finerenone on HHF.

Bi-directional signaling between the intestinal epithelium and type-3 innate lymphoid cells regulates secretory dynamics and interleukin-22.

Type-3 innate lymphoid cells (ILC3) respond to localized environmental cues to regulate homeostasis and orchestrate immunity in the intestine. The intestinal epithelium is an important upstream regulator and downstream target of ILC3 signaling, however, the complexity of mucosal tissues can hinder efforts to define specific interactions between these two compartments. Here, we employ a reductionist co-culture system of murine epithelial small intestinal organoids (SIO) with ILC3 to uncover bi-directional signaling mechanisms that underlie intestinal homeostasis. We report that ILC3 induce global transcriptional changes in intestinal epithelial cells, driving the enrichment of secretory goblet cell signatures. We find that SIO enriched for goblet cells promote NKp46+ ILC3 and interleukin (IL)-22 expression, which can feedback to induce IL-22-mediated epithelial transcriptional signatures. However, we show that epithelial regulation of ILC3 in this system is contact-dependent and demonstrate a role for epithelial Delta-Like-Canonical-Notch-Ligand (Dll) in driving IL-22 production by ILC3, via subset-specific Notch1-mediated activation of T-bet+ ILC3. Finally, by interfering with Notch ligand-receptor dynamics, ILC3 appear to upregulate epithelial Atoh1 to skew secretory lineage determination in SIO-ILC3 co-cultures. This research outlines two complimentary bi-directional signaling modules between the intestinal epithelium and ILC3, which may be relevant in intestinal homeostasis and disease.

The importance of SNOMED CT concept specificity in healthcare analytics.

BACKGROUND: Healthcare data frequently lack the specificity level needed to achieve clinical and operational objectives such as optimising bed management. Pneumonia is a disease of importance as it accounts for more bed days than any other lung disease and has a varied aetiology. The condition has a range of SNOMED CT concepts with different levels of specificity. OBJECTIVE: This study aimed to quantify the importance of the specificity of an SNOMED CT concept, against well-established predictors, for forecasting length of stay for pneumonia patients. METHOD: A retrospective data analysis was conducted of pneumonia admissions to a tertiary hospital between 2011 and 2021. For inclusion, the primary diagnosis was a subtype of bacterial or viral pneumonia, as identified by SNOMED CT concepts. Three linear mixed models were constructed. Model One included known predictors of length of stay. Model Two included the predictors in Model One and SNOMED CT concepts of lower specificity. Model Three included the Model Two predictors and the concepts with higher specificity. Model performances were compared. RESULTS: Sex, ethnicity, deprivation rank and Charlson Comorbidity Index scores (age-adjusted) were meaningful predictors of length of stay in all models. Inclusion of lower specificity SNOMED CT concepts did not significantly improve performance (ΔR2 = 0.41%, p = .058). SNOMED CT concepts with higher specificity explained more variance than each of the individual predictors (ΔR2 = 4.31%, p < .001). CONCLUSION: SNOMED CT concepts with higher specificity explained more variance in length of stay than a range of well-studied predictors. IMPLICATIONS: Accurate and specific clinical documentation using SNOMED CT can improve predictive modelling and the generation of actionable insights. Resources should be dedicated to optimising and assuring clinical documentation quality at the point of recording.