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Mild malformation of cortical development with oligodendroglial hyperplasia in epilepsy (MOGHE) is an important cause of drug-resistant epilepsy. A significant subset of individuals diagnosed with MOGHE display somatic mosaicism for loss-of-function variants in SLC35A2, which encodes the UDP-galactose transporter. We developed a mouse model to investigate how disruption of this transporter leads to a malformation of cortical development. We used in utero electroporation and CRISPR/Cas9 to knockout Slc35a2 in a subset of layer 2/3 cortical neuronal progenitors in the developing brains of male and female fetal mice to model mosaic expression. Mosaic Slc35a2 knockout was verified through next-generation sequencing and immunohistochemistry of GFP-labelled transfected cells. Histology of brain tissue in mosaic Slc35a2 knockout mice revealed the presence of upper layer-derived cortical neurons in the white matter. Reconstruction of single filled neurons identified altered dendritic arborisation with Slc35a2 knockout neurons having increased complexity. Whole-cell electrophysiological recordings revealed that Slc35a2 knockout neurons display reduced action potential firing, increased afterhyperpolarisation duration and reduced burst-firing when compared with control neurons. Mosaic Slc35a2 knockout mice also exhibited significantly increased epileptiform spiking and increased locomotor activity. We successfully generated a mouse model of mosaic Slc35a2 deficiency, which recapitulates features of the human phenotype, including impaired neuronal migration. We show that knockout in layer 2/3 cortical neuron progenitors is sufficient to disrupt neuronal excitability, increase epileptiform activity and cause hyperactivity in mosaic mice. Our mouse model provides an opportunity to further investigate the disease mechanisms that contribute to MOGHE and facilitate the development of precision therapies.

Study objective: This study examined the association between frailty and incident cardiovascular disease (CVD) events, major adverse cardiovascular events (MACE), and CVD-related mortality. Design: Longitudinal cohort study. Setting: The ASPirin in Reducing Events in the Elderly (ASPREE) clinical trial in Australia and the United States. Participants: 19,114 community-dwelling older adults (median age 74.0 years; 56.4 % females). Interventions: Pre-frailty and frailty were assessed using a modified Fried phenotype and a deficit accumulation Frailty Index (FI) at baseline. Main outcome measures: CVD was defined as a composite of CVD death, non-fatal myocardial infarction, non-fatal stroke, and hospitalization for heart failure; MACE included all except heart failure. Cox proportional hazards regression was used to analyze the association between frailty and CVD outcomes over a median follow-up of 4.7 years. Results: Baseline pre-frail and frail groups had a higher risk of incident CVD events (Hazard Ratio (HR): 1.31; 95 % Confidence Interval (CI): 1.14–1.50 for pre-frail and HR: 1.63; 95 % CI: 1.15–2.32 for frail) and MACE (pre-frail HR: 1.26; 95 % CI: 1.08–1.47 and frail HR: 1.51; 95 % CI: 1.00–2.29) than non-frail participants according to Fried phenotype after adjusting for traditional CVD risk factors. Effect sizes were similar or larger when frailty was assessed with FI; similar results for men and women. Conclusion: Frailty increases the likelihood of developing CVD, including MACE, in community-dwelling older men and women without prior CVD events. Screening for frailty using Fried or FI method could help identify community-dwelling older adults without prior CVD events who are more likely to develop CVD, including MACE, and may facilitate targeted preventive measures to reduce their risk.

Rationale & Objective: Variability in estimated glomerular filtration rate (eGFR) over time is often observed, but it is unknown whether this variation is clinically important. We investigated the association between eGFR variability and survival free of dementia or persistent physical disability (disability-free survival) and cardiovascular disease (CVD) events (myocardial infarction, stroke, hospitalization for heart failure, or CVD death). Study Design: Post hoc analysis. Setting & Participants: 12,549 participants of the ASPirin in Reducing Events in the Elderly trial. Participants were without documented dementia, major physical disability, previous CVD, and major life-limiting illness at enrollment. Predictors: eGFR variability. Outcomes: Disability-free survival and CVD events. Analytical Approach: eGFR variability was estimated using the standard deviation of eGFR measurements obtained from participants’ baseline, first, and second annual visits. Associations between tertiles of eGFR variability with disability-free survival and CVD events occurring after the eGFR variability estimation period were examined. Results: During median follow-up of 2.7 years after the second annual visit, 838 participants died, developed dementia, or acquired a persistent physical disability; 379 had a CVD event. The highest tertile of eGFR variability had an increased risk of death/dementia/disability (HR, 1.35; 95% CI, 1.14-1.59) and CVD events (HR, 1.37; 95% CI, 1.06-1.77) compared with the lowest tertile after covariate adjustment. These associations were present in patients with and without chronic kidney disease at baseline. Limitations: Limited representation of diverse demographics. Conclusions: In older, generally healthy adults, higher variability in eGFR over time predicts increased risk of future death/dementia/disability and CVD events.

Genetic variation in voltage-gated sodium (NaV) channels is a significant contributor to neurodevelopmental disorders. NaV channel alpha subunits are encoded by the SCNxA family and four are predominately expressed in the brain: SCN1A, SCN2A, SCN3A, and SCN8A. Gene expression is developmentally regulated, and they are known to express functionally distinct transcript variants. Precision therapies targeting these genes and their transcript variants are currently in preclinical development, yet the developmental expression of these transcripts in the human brain is yet to be fully understood. Additionally, the functional consequences of some mutations differ depending on the studied channel isoform, suggesting differential transcript variant expression can affect disease prognoses. We characterise the expression of the four SCNxAs and their transcript variants in human, Rhesus monkey and mouse brain using publicly available RNA-sequencing data and analysis tools, demonstrating that this approach can be used to answer important biological questions of gene and transcript developmental regulation. We find that gene expression and transcript variant regulation are conserved across species at similar developmental stages and determine the developmental milestones for transcript variant expression. Our study provides a guide to researchers testing therapies and clinicians advising prognoses based on the expression of channel isoforms.

Study objective: The aim of this study was to identify whether physical component score (PCS) of health-related quality of life trajectories over 4.7-years predicted subsequent risk of incident fatal and non-fatal CVD events, and all-cause mortality. Methods: This study included 16,871 community-dwelling people aged ≥65 years enrolled in the ASPREE (ASPirin in Reducing Events in the Elderly) trial. PCS was assessed annually using the SF-12 (version-2) over a median 4.7-years (i.e. from baseline (2010–2014) till June 2017). Incident CVD events and all-cause mortality occurring after June 2017 until the second-year after the end of the trial were considered. Growth mixture and logistic regression modelling were used. Results: Four PCS trajectories were identified: high (66.5%), intermediate (13.3%), decline (13.8%), and low (6.5%), and there was subsequently a total of 406 (2.50%) incident CVD events, 197 (1.17%) fatal CVD, and 751 (4.45%) deaths. The declining PCS trajectory group had the highest risk of incident CVD (adjusted OR, 1.51; 95%CI 1.14, 1.99), while the low PCS trajectory group had the greatest risk of fatal CVD (adjusted OR, 1.74; 95%CI 1.06, 2.85) and all-cause mortality (adjusted OR, 1.83; 95%CI 1.40, 2.40). After further adjustment for the baseline PCS score, only the association between declining PCS trajectory and incident CVD (adjusted OR, 1.51; 95%CI 1.11, 2.07) remained. Conclusion: Our study strengthens the importance of PCS as a predictive measure of CVD and all-cause mortality in older people and also highlights that a declining PCS trajectory could be considered an early predictor of future CVD events.

Background: Fibrinolysis is an important reperfusion strategy in the management of ST-elevation myocardial infarction (STEMI) when timely access to primary percutaneous coronary intervention (PPCI) is unavailable. Rescue PCI is generally thought to have worse outcomes than PPCI in STEMI. We aimed to determine short- and long-term outcomes of patients with rescue PCI versus PPCI for treatment of STEMI. Methods and results: Patients admitted with STEMI (excluding out-of-hospital cardiac arrest) within the Melbourne Interventional Group (MIG) registry between 2005 and 2018 treated with either rescue PCI or PPCI were included in this retrospective cohort analysis. Comparison of 30-day major adverse cardiac events (MACE) and long-term mortality between the two groups was performed. There were 558 patients (7.1%) with rescue PCI and 7271 with PPCI. 30-day all-cause mortality (rescue PCI 6% vs. PPCI 5%, p = 0.47) and MACE (rescue PCI 10.3% vs. PPCI 8.9%, p = 0.26) rates were similar between the two groups. Rates of in-hospital major bleeding (rescue PCI 6% vs. PPCI 3.4%, p = 0.002) and 30-day stroke (rescue PCI 2.2% vs. PPCI 0.8%, p

Background: Little is known about percutaneous coronary intervention (PCI) practices and outcomes in low-and middle-income nations, despite its rapid uptake across Asia. For the first time, we report on clinical characteristics and in-hospital outcomes for patients undergoing PCI at a leading cardiac centre in Vietnam. Methods: Information on characteristics, treatments, and outcomes of patients undergoing PCI was collected into the first PCI registry through direct interviews using a standardised form, medical record abstraction, and reading PCI imaging data on secured disks. Subgroup analysis was also conducted to explore gender differences. Results: Between September 2017 and May 2018, 1022 patients undergoing PCI were recruited from a total of 1041 procedures. The mean age was 68.3 years and two thirds were male. While 54.4% of patients presented with acute coronary syndromes, the rate of ST-elevation myocardial infarction was 14.5%. The majority of lesions were classified as type B2 and C and the radial artery was the most common access location for PCI (79.2%). The use of drug-eluting stents was universal and the angiographic success rate was 99.4%. Cardiac complications following PCI were rare with the exception of major bleeding (2.0%). Female patients were older with relatively more comorbidities and a higher incidence of major bleeding than males (p

Purpose: To describe the baseline participant characteristics in the ASPREE-AMD study, investigating the effect of aspirin on AMD incidence and progression. Methods: Australian participants from the ASPirin in Reducing Events in the Elderly (ASPREE) trial, randomized to 100 mg aspirin daily or placebo, had non-mydriatic, digital color fundus images graded according to the Beckman AMD classification. Associations with AMD were determined for baseline characteristics and genetic risk variants. Results: ASPREE-AMD sub-study enrolled 4993 participants with gradable macular images. Median age was 73.4 years (IQR, 71.5, 76.6), 52% were female, 10% had diabetes mellitus, 73% had hypertension, and 44% were former/current smokers. Early, intermediate and late AMD (detected in 20.6%, 16.1%, 1.1%, respectively), significantly associated with age, were also associated with increasing HDL levels: OR = 1.52 (95%CI, 1.26, 1.84), OR = 1.43 (1.17, 1.77) and OR = 1.96 (1.02, 3.76), respectively. Female sex was associated with early [OR = 1.37 (1.16, 1.62)], and intermediate [OR = 1.35 (1.12, 1.63)] AMD, as was previous regular use of aspirin, with OR = 1.46 (1.11, 1.92) and OR = 1.37 (1.01, 1.85), respectively. Current smoking had increased odds for late AMD, OR = 4.02 (1.42, 11.36). Genetic risk variant rs3750846 (ARMS2/HTRA1) was associated with each AMD stage (p

The GABAAγ2(R43Q) mouse is an established model of absence epilepsy displaying spontaneous spike-and-wave discharges (SWD) and associated behavioral arrest. Absence epilepsy typically results from cortico-thalamic networks. Nevertheless, there is increasing evidence for changes in hippocampal metabolism and electrical behavior, consistent with a link between absence seizures and hippocampus-related co-morbidities. Hyperpolarization-activated-cyclic-nucleotide-gated (HCN) channels are known to be transcriptionally regulated in a number of seizure models. Here we investigate the expression and function of these channels in the hippocampus of the genetic epilepsy model. A reduction in HCN1, but not HCN2 transcript, was observed in GABAAγ2(R43Q) mice relative to their littermate controls. In contrast, no change in HCN1 transcript was noted at an age prior to seizure expression or in a SWD-free model in which the R43Q mutation has been crossed into a seizure-resistant genetic background. Whole-cell recordings from CA1 pyramidal neurons confirm a reduction in Ih in the GABAAγ2(R43Q) mouse. Further, a left-shift in half-activation of the Ih conductance–voltage relationship is consistent with a reduction in HCN1 with no change in HCN2 channel expression. Behavioral analysis using the Morris water maze indicates that GABAAγ2(R43Q) mice are unable to learn as effectively as their wildtype littermates suggesting a deficit in hippocampal-based learning. SWD-free mice harboring the R43Q mutation had no learning deficit. We conclude that SWDs reduce hippocampal HCN1 expression and function, and that the reduction associates with a spatial learning deficit.

Follistatin (Fst) functions to bind and neutralize the activity of members of the transforming growth factor-β superfamily. Fst has a well-established role in skeletal muscle, but we detected significant Fst expression levels in interscapular brown and subcutaneous white adipose tissue, and further investigated its role in adipocyte biology. Fst expression was induced during adipogenic differentiation of mouse brown preadipocytes and mouse embryonic fibroblasts (MEFs) as well as in cold-induced brown adipose tissue from mice. In differentiated MEFs from Fst KO mice, the induction of brown adipocyte proteins including uncoupling protein 1, PR domain containing 16, and PPAR gamma coactivator-1α was attenuated, but could be rescued by treatment with recombinant FST. Furthermore, Fst enhanced thermogenic gene expression in differentiated mouse brown adipocytes and MEF cultures from both WT and Fst KO groups, suggesting that Fst produced by adipocytes may act in a paracrine manner. Our microarray gene expression profiling of WT and Fst KO MEFs during adipogenic differentiation identified several genes implicated in lipid and energy metabolism that were significantly downregulated in Fst KO MEFs. Furthermore, Fst treatment significantly increases cellular respiration in Fst-deficient cells. Our results implicate a novel role of Fst in the induction of brown adipocyte character and regulation of energy metabolism.

Introduction: We conducted a double-blind randomised controlled trial in a remote-living Australian Aboriginal group at high risk for chronic disease to assess whether pharmacological treatment with angiotensin converting enzyme inhibitor (ACEi) could delay the onset of albuminuria, hypertension or diabetes in people currently free of those conditions. Methods: Eligibility criteria in 2008 were age ≥18yr, blood pressure ≤140/90 mm/Hg, urinary albumin creatinine ratio (ACR) 140/90 mm Hg and/or haemoglobin A1c >6.5%, and/or cardiovascular events. Results were analysed in 125 randomised participants who commenced treatment. Results: Recruitment was low, especially of women, and dropout rates high: there were finally 60 and 65 people in the ACEi and placebo groups respectively. In females, there were no events among 10 in the ACEi group, versus 5 events among 17 in the placebo group, and longitudinal ACR, HbA1c and blood pressure levels supported probable benefit of ACEi. There was no benefit of ACEi in males, but a probable benefit on diabetes/hypertension events. With the genders combined, there was probable reduction of diabetes (zero vs 4 events, p = 0.068), and of diabetes or hypertension (zero vs 5 events, p = 0.037). Discussion: In this high-risk population, ACEi probably delays development of albuminuria, diabetes and hypertension in females, and of non-ACR events overall. Repeat investigation with a larger sample size is warranted. Keywords: Indigenous Australian, Albuminuria/hypertension, Diabetes, Randomised controlled trial, Angiotensin converting enzyme inhibitor (ACEi), Remote-living