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Lipid metabolism plays an instructive role in regulating stem cell state and differentiation. However, the roles of lipid mobilization and utilization in stem cell-driven regeneration are unclear. Planarian flatworms readily restore missing tissue due to injury-induced activation of pluripotent somatic stem cells called neoblasts. Here, we identify two intestine-enriched orthologs of apolipoprotein b, apob-1 and apob-2, which mediate transport of neutral lipid stores from the intestine to target tissues including neoblasts, and are required for tissue homeostasis and regeneration. Inhibition of apob function by RNAi causes head regression and lysis in uninjured animals, and delays body axis re-establishment and regeneration of multiple organs in amputated fragments. Furthermore, apob RNAi causes expansion of the population of differentiating neoblast progeny and dysregulates expression of genes enriched in differentiating and mature cells in eight major cell type lineages. We conclude that intestine-derived lipids serve as a source of metabolites required for neoblast progeny differentiation. Lipid metabolism regulates stem cell states and differentiation. Here, the authors demonstrate a requirement in planarians for Apolipoprotein B-mediated neutral lipid transport from intestinal stores to stem cells and their progeny during differentiation and whole-body regeneration. [ABSTRACT FROM AUTHOR]

Background: Prognostication of myeloproliferative neoplasm (MPN) has always been challenging, even with the advent of Janus kinase 2 (JAK2 V617F) molecular studies. The survival pattern of patients diagnosed with MPN in developing countries is still undetermined. Materials and methods: The national MPN registry conducted from 2009 to 2015 in Malaysia provided a comprehensive insight into the demographics, clinical characteristics and laboratory parameters of patients diagnosed with MPN nationwide. The study analysed the survival patterns and mortality outcomes and risk among 671 patients diagnosed with essential thrombocythaemia (ET), polycythaemia vera (PV), primary myelofibrosis (PMF) and unclassified MPN (MPN-U). Mortality status was traced and confirmed until the end of December 2018, with right censoring applied to patients alive beyond that. Results: The analysed cohort consisted of 283 (42.2%) ET, 269 (40.1%) PV, 62 (9.2%) PMF and 57 (8.5%) MPN-U incident cases with diagnosis made between 2007 and 2015. The majority of patients were male (52.3%) and Malay (48.9%), except for ET, in which the majority of patients were female (60.1%) and of Chinese origin (47.0%). Female patients were found to have significantly better overall survival (OS) rates in ET (p = 0.0285) and MPN-U (p = 0.0070). Patients with JAK2 V617F mutation were found to have marginally inferior OS over time. Multivariable Cox regression identified patients with increased age [hazard ratio (HR) 1.055, 95% CI 1.031; 1.064], reduced haemoglobin (HB) level (HR 0.886, 95% CI 0.831; 0.945, p = 0.0002), being male (HR 1.545, 95% CI 1.077; 2.217, p = 0.0182), and having MPN-U (HR 2.383, 95% CI 1.261; 4.503, p = 0.0075) and PMF (HR 1.975, 95% CI 1.054; 3.701, p = 0.0335) at increased risk for worse mortality outcomes. Conclusion: Myeloproliferative neoplasm reduces patient survival. The degree of impact on survival varies according to sub-type, sex, bone marrow fibrosis and HB levels. The JAK2 V617F mutation was not found to affect the survival pattern or mortality outcome significantly. [ABSTRACT FROM AUTHOR]

Human error has been implicated as a causal factor in a large proportion of road accidents. Automated driving systems purport to mitigate this risk, but self-driving systems that allow a driver to entirely disengage from the driving task also require the driver to monitor the environment and take control when necessary. Given that sleep loss impairs monitoring performance and there is a high prevalence of sleep deficiency in modern society, we hypothesized that supervising a self-driving vehicle would unmask latent sleepiness compared to manually controlled driving among individuals following their typical sleep schedules. We found that participants felt sleepier, had more involuntary transitions to sleep, had slower reaction times and more attentional failures, and showed substantial modifications in brain synchronization during and following an autonomous drive compared to a manually controlled drive. Our findings suggest that the introduction of partial self-driving capabilities in vehicles has the potential to paradoxically increase accident risk. [ABSTRACT FROM AUTHOR]

Intravenously administered tissue plasminogen activator (IV-tPA), dose determined by patients' body-weight, remains the only approved drug treatment for acute ischemic stroke (AIS). Since a shorter onset-to-treatment time results in better functional outcome, treatment is often initiated according to the estimated or last-known body-weight of the patient. This approach may result in underdosing or overdosing of tPA. In this multicenter retrospective study, we evaluated the extent of error in tPA dosing in our AIS cohort and its impact on functional outcome and symptomatic intracranial hemorrhage (SICH). Consecutive AIS patients, receiving IV-tPA, dose determined by the estimated body-weight, at three tertiary centers between January and December 2017 were included. Collected data included information about demographics, cardiovascular risk factors, stroke subtype and National Institute of Health Stroke Scale (NIHSS) score. Estimated and measured body-weights were recorded. Modified Rankin scale (mRS) of 2 or more defined unfavorable outcome. The study included 150 patients. Median age was 64 -years (IQR 55–75) with male preponderance (67%) and median NIHSS score of 9 points (IQR 6–17). Mean measured weight of our study population was 58 (SD 13) kg. Median difference between actual and estimated body-weight was 3 kg (IQR 1.5–6). Difference was more than 10% in 35 (23.3%) patients. Good functional outcome (mRS 0–1) was achieved by 74 (49.3%) patients and 10 (6.8%) developed SICH. NIHSS (OR 1.288; 95% CI 1.157–1.435, p < 0.001) and large artery atherosclerosis (OR 5.878; 95% CI 1.929–17.910, p = 0.002) were independent predictors of unfavorable functional outcome. Our finding of the statistically insignificant 2.5-fold increase in poor outcomes among patients where the estimated and actual weight differed by more than 10% should be interpreted with caution due to the limited sample size. Significant difference occurs between estimated and actual body-weight in a considerable proportion of thrombolysed AIS patients. However, this discrepancy does not affect functional outcome or the risk of SICH. [ABSTRACT FROM AUTHOR]

The Coronavirus disease 2019 (COVID-19) pandemic is rapidly evolving and affecting healthcare systems across the world. Singapore has escalated its alert level to Disease Outbreak Response System Condition (DORSCON) Orange, signifying severe disease with community spread. We aimed to study the overall volume of AIS cases and the delivery of hyperacute stroke services during DORSCON Orange. This was a single-centre, observational cohort study performed at a comprehensive stroke centre responsible for AIS cases in the western region of Singapore, as well as providing care for COVID-19 patients. All AIS patients reviewed as an acute stroke activation in the Emergency Department (ED) from November 2019 to April 2020 were included. System processes timings, treatment and clinical outcome variables were collected. We studied 350 AIS activation patients admitted through the ED, 206 (58.9%) pre- and 144 during DORSCON Orange. Across the study period, number of stroke activations showed significant decline (p = 0.004, 95% CI 6.513 to − 2.287), as the number of COVID-19 cases increased exponentially, whilst proportion of activations receiving acute recanalization therapy remained stable (p = 0.519, 95% CI − 1.605 to 2.702). Amongst AIS patients that received acute recanalization therapy, early neurological outcomes in terms of change in median NIHSS at 24 h (-4 versus -4, p = 0.685) were largely similar between the pre- and during DORSCON orange periods. The number of stroke activations decreased while the proportion receiving acute recanalization therapy remained stable in the current COVID-19 pandemic in Singapore. [ABSTRACT FROM AUTHOR]

Beta-thalassemia is one of the most prevalent inherited diseases and a public health problem in Malaysia. Malaysia is geographically divided into West and East Malaysia. In Sabah, a state in East Malaysia, there are over 1000 estimated cases of β-thalassemia major patients. Accurate population frequency data of the molecular basis of β-thalassemia major are needed for planning its control in the high-risk population of Sabah. Characterization of β-globin gene defects was done in 252 transfusion dependent β-thalassemia patients incorporating few PCR techniques. The study demonstrates that β-thalassemia mutations inherited are ethnically dependent. It is important to note that 86.9% of transfusion-dependent β-thalassemia major patients in Sabah were of the indigenous population and homozygous for a single mutation. The Filipino β0-deletion was a unique mutation found in the indigenous population of Sabah. Mutations common in West Malaysia were found in 11 (4.3%) patients. Four rare mutations (Hb Monroe, CD 8/9, CD 123/124/125 and IVS I-2) were also found. This study is informative on the population genetics of β-thalassemia major in Sabah. [ABSTRACT FROM AUTHOR]

Patients with globus pharyngeus referred for barium swallow pharyngoesophagography in a local hospital from 1/7/1999 to 30/6/2009 were identified. Their fluoroscopic images were reviewed, and their outcomes were used as gold standard. A total of 908 patients with globus pharyngeus were referred for barium swallow in the period. There were 783 patients with normal barium swallow and 125 patients with abnormal barium swallow findings. All patients aged below 30 years had normal barium swallow result and unremarkable follow up. The sensitivity and specificity of barium swallow were 25.6 and 97.5% respectively; and the positive predictive value and negative predictive value were 61.5 and 89.1% respectively. The overall accuracy was 87.6%. Barium swallow is of limited diagnostic value in patients with typical globus pharyngeus, and it is not recommended in these patients, especially with young age. [ABSTRACT FROM AUTHOR]