Dense reinforcement learning for safety validation of autonomous vehicles.

One critical bottleneck that impedes the development and deployment of autonomous vehicles is the prohibitively high economic and time costs required to validate their safety in a naturalistic driving environment, owing to the rarity of safety-critical events1. Here we report the development of an intelligent testing environment, where artificial-intelligence-based background agents are trained to validate the safety performances of autonomous vehicles in an accelerated mode, without loss of unbiasedness. From naturalistic driving data, the background agents learn what adversarial manoeuvre to execute through a dense deep-reinforcement-learning (D2RL) approach, in which Markov decision processes are edited by removing non-safety-critical states and reconnecting critical ones so that the information in the training data is densified. D2RL enables neural networks to learn from densified information with safety-critical events and achieves tasks that are intractable for traditional deep-reinforcement-learning approaches. We demonstrate the effectiveness of our approach by testing a highly automated vehicle in both highway and urban test tracks with an augmented-reality environment, combining simulated background vehicles with physical road infrastructure and a real autonomous test vehicle. Our results show that the D2RL-trained agents can accelerate the evaluation process by multiple orders of magnitude (103 to 105 times faster). In addition, D2RL will enable accelerated testing and training with other safety-critical autonomous systems.

Shared decision-making related to treatment of haemophilia: A scoping review of influential factors and available support tools.

INTRODUCTION: Treatment selection in haemophilia is increasingly challenging given evolving therapeutic options and the need for individualization. Shared decision-making (SDM) approaches have recently gained interest, though a synthesis of available studies is lacking. AIM: A scoping review was conducted to summarize literature reporting on factors impacting treatment SDM in haemophilia and tools or models available to support such decisions. METHODS: PubMed, Embase, the Cochrane Library, Web of Science and grey literature were searched for studies published through August 2023. Original studies reporting on facilitators and barriers to haemophilia SDM and SDM tools were included and analyzed for themes, characteristics and gaps. RESULTS: A total of 625 records were identified and 14 unique studies were selected (factors influencing treatment SDM, n = 7; SDM tools, n = 7). The studies typically included input from persons with haemophilia, caregivers and healthcare practitioners (HCPs). Thematic organization of factors influencing SDM revealed three main categories: knowledge, patient characteristics and HCP-patient interactions. Availability of information was a commonly reported facilitator of SDM, while poor HCP-patient engagement was a commonly reported barrier. Tools varied in focus, with some facilitating general treatment SDM while others supported selection of certain therapy types. The studies underscored additional factors critical for SDM, such as alignment of HCP-patient perceptions, shared language and tailoring of tools to specific subpopulations. CONCLUSION: Few studies report on treatment SDM factors and tools in haemophilia; available tools vary considerably. It remains unclear whether published tools have been successfully implemented into clinical practice. Additional research is warranted.

Impact of inherited bleeding disorders on maternal bleeding and other pregnancy outcomes: A population-based cohort study.

INTRODUCTION: Increasing rate of postpartum haemorrhage (PPH) has been observed between 2003 and 2010 in Canada. Inherited bleeding disorders contribute to the risk of PPH. AIM: To identify the trend in PPH in the last decade, assess the impact of bleeding disorders on pregnancy outcomes and evaluate their coagulation workup during pregnancy. METHODS: We conducted a population-based retrospective cohort study using the Alberta Pregnancy Birth Cohort from 2010 to 2018. We included women with von Willebrand disease (VWD) and haemophilia, identified by previously validated algorithm and matched with controls. Logistic regression was used to compute odds of PPH and other pregnancy outcomes. RESULTS: We identified 311,330 women with a total of 454,400 pregnancies with live births. The rate of PPH did not change significantly from 10.13 per 100 deliveries (95% CI 10.10-10.16) in 2010-10.72 (95% CI 10.69-10.75) in 2018 (p for trend = .35). Women with bleeding disorders were significantly more likely to experience PPH (odds ratio [OR] 2.3; 95% CI 1.5-3.6), antepartum haemorrhage (OR 2.9; 95% CI 1.5-5.9) and red cell transfusion (OR 2.8; 95% CI 1.1-7.0). We observed a nonsignificant rise in the rate of PPH in women with VWD and haemophilia. Only 49.5% pregnancies with bleeding disorders had third trimester coagulation factor levels checked. Higher odds of PPH and antepartum haemorrhage were observed even with factor levels ≥0.50 IU/mL in third trimester. CONCLUSION: Despite comprehensive care in women with bleeding disorders, they are still at higher risk of adverse pregnancy outcomes compared to population controls.

Thrombopoietin Receptor Agonists and Other Second-Line Therapies for Immune Thrombocytopenia: A Narrative Review With a Focus on Drug Access in Canada.

INTRODUCTION: Immune thrombocytopenia (ITP) is an autoimmune disease characterized by low platelet counts and increased risk of bleeding. After corticosteroids with or without intravenous immune globulin (first-line treatment), second-line treatment options include rituximab, splenectomy, thrombopoietin receptor agonists (TPO-RAs), and fostamatinib. In Canada, the choice of second-line therapy is influenced by access to medications. The goals of this narrative review are to 1) summarize the evidence for the use of TPO-RAs and other second-line therapies in ITP and 2) highlight differences in public funding criteria for TPO-RAs across provinces and territories in Canada. METHODS: We conducted a literature review of second-line therapies for ITP. We solicited information on public funding programs for TPO-RAs in Canada from health care providers, pharmacists, and provincial ministries of health. RESULTS: Head-to-head trials involving TPO-RAs, rituximab, splenectomy, and fostamatinib are lacking. There is substantial evidence of effect for TPO-RAs in improving platelet count levels, health-related quality of life, bleeding, and fatigue from placebo-controlled trials and observational studies; however, access to TPO-RAs through provincial funding programs in Canada is variable. Splenectomy failure is a prerequisite for the funding of TPO-RAs in Ontario, Manitoba, and Saskatchewan, but not in Alberta or Quebec. Other provinces either do not have access to public funding or funding is provided on a case-by-case basis. DISCUSSION: TPO-RAs are effective second-line therapies for the treatment of ITP; however, access is variable across Canada, which results in health disparities and poor uptake of international treatment guidelines.

A framework for assessing the impacts of land-use/cover change and climate change on wheat productivity under 1.5 and 2.0 °C warming at watershed scale.

BACKGROUND: Irrigation is used extensively to enhance grain production and ensure food security. Many studies have used crop models and global climate models to study the variation of irrigated crop yield in the context of climate change. But most considered the influence of direct climate change but neglected the influence of irrigation water availability, which is affected by land-use/cover change (LUCC) and indirect climate change, on irrigated crop yield. This study therefore developed a framework including Patch-generating Land Use Simulation model, Soil and Water Assessment Tool, Agricultural Production Systems sImulator Model, and global climate models for exploring the impacts of LUCC, direct climate change, and indirect climate change on wheat yield in a typical watershed. RESULTS: Both LUCC and climate change caused increased runoff from October to May, and thus increased the irrigation water availability, by 51.6 and 30.7 mm per growing season under 1.5 and 2.0 °C warming, respectively. The combined influence of LUCC, direct, and indirect climate change increased wheat yield by about 18.5% and 15.5% in the context of 1.5 and 2.0 °C warming, respectively. The relative contribution of LUCC, indirect climate change and direct climate change to yield was 4.7%, 41.2%, and 54.1% under 1.5 °C warming, and 13.1%, 28.7%, and 58.2% under 2.0 °C warming, respectively. CONCLUSION: We suggest that changes in irrigation water availability should be considered from a watershed perspective when simulating the influence of climate change on crop yield, especially regional crop production estimation. © 2023 Society of Chemical Industry.

Increased acute care utilisation, comorbidities and mortality in adults with haemophilia: A population-based cohort study from 2012 to 2019.

INTRODUCTION: Improvements in treatment strategies have led to increased life expectancy of persons with haemophilia (PWH). Consequently, age-related comorbidities become increasingly relevant. AIM: To evaluate the prevalence of age-related comorbidities, mortality, health service utilisation and predictors of hospitalisation in PWH compared to the general population. METHODS: We conducted a population-based retrospective cohort study using linked administrative data. Men with haemophilia were identified in Alberta, Canada (2012-2019) with a validated case definition and were age-matched with male population controls. We calculated the prevalence of major comorbidities, all-cause mortality, and examined health service utilisation including Emergency Department visits and hospitalisations. Logistic regression was applied to identify predictors of hospitalisation. RESULTS: We identified 198 and 329 persons with moderately severe haemophilia and mild/moderate, respectively. Moderately severe haemophilia had a higher risk of death (standardised mortality ratio 3.2, 95% confidence interval [CI] 1.4-6.3) compared to the general population. PWH had a significantly higher prevalence of hypertension, liver diseases and malignancies than controls. Moderately severe haemophilia was associated with significantly higher rates of hospitalisations (52.5% vs. 14.5%), Emergency Department visits (89.1% vs. 62.7%) and intensive care admissions (8.9% vs. 2.3%). Age > 65 years (adjusted odds ratio [aOR] 6.8) and presence of multiple comorbidities (aOR 3.9) were significant predictors of hospitalisations among PWH. CONCLUSION: Despite advanced care, haemophilia is associated with higher acute care utilisation than the general population, highlighting the substantial burden of illness on patients and the health care system.

CuI-p-DPA coordination polymer isomers for "turn-on" fluorescence detection of thiophanate-methyl.

Three copper iodide coordination polymer (CuI-p-DPA) isomers were prepared from the fluorescent organic ligand p-DPA and cuprous iodide (CuI) under different solvothermal conditions, which exhibited quenched fluorescence behaviors after forming coordination polymers (CPs). These CuI-p-DPA isomers showed discrepant fluorescence responses to thiophanate-methyl (TM). Among these CuI-p-DPA isomers, α-CuI-p-DPA exhibited the maximum fluorescence enhancement after its incubation with TM in aqueous solution. The fluorescence enhancement mechanism was that TM competed with the ligand p-DPA to coordinate with CuI clusters, and then α-CuI-p-DPA released p-DPA into the solution and induced fluorescence enhancement. The present detection method possesses the advantages of good selectivity, high sensitivity, short response time, and strong anti-interference ability with a linear range of 0.5-100 µM and a detection limit of 0.01 µM. This study not only reveals that the spatial structures of CPs play an important role in the fluorescence response ability, but also provide a new fluorescence signal-on analysis method to rapidly and sensitively determine the pesticide residue for TM.

Malonyl-CoA Accumulation as a Compensatory Cytoprotective Mechanism in Cardiac Cells in Response to 7-Ketocholesterol-Induced Growth Retardation.

The major oxidized product of cholesterol, 7-Ketocholesterol (7KCh), causes cellular oxidative damage. In the present study, we investigated the physiological responses of cardiomyocytes to 7KCh. A 7KCh treatment inhibited the growth of cardiac cells and their mitochondrial oxygen consumption. It was accompanied by a compensatory increase in mitochondrial mass and adaptive metabolic remodeling. The application of [U-13C] glucose labeling revealed an increased production of malonyl-CoA but a decreased formation of hydroxymethylglutaryl-coenzyme A (HMG-CoA) in the 7KCh-treated cells. The flux of the tricarboxylic acid (TCA) cycle decreased, while that of anaplerotic reaction increased, suggesting a net conversion of pyruvate to malonyl-CoA. The accumulation of malonyl-CoA inhibited the carnitine palmitoyltransferase-1 (CPT-1) activity, probably accounting for the 7-KCh-induced suppression of ß-oxidation. We further examined the physiological roles of malonyl-CoA accumulation. Treatment with the inhibitor of malonyl-CoA decarboxylase, which increased the intracellular malonyl-CoA level, mitigated the growth inhibitory effect of 7KCh, whereas the treatment with the inhibitor of acetyl-CoA carboxylase, which reduced malonyl-CoA content, aggravated such a growth inhibitory effect. Knockout of malonyl-CoA decarboxylase gene (Mlycd-/-) alleviated the growth inhibitory effect of 7KCh. It was accompanied by improvement of the mitochondrial functions. These findings suggest that the formation of malonyl-CoA may represent a compensatory cytoprotective mechanism to sustain the growth of 7KCh-treated cells.

Quantitative optical diagnostics on macroscopic soot onset for ethylene diffusion flames with ethyl ester addition.

A novel quantitative optical diagnostics method for determining the threshold of soot onset in counterflow diffusion flames was proposed and demonstrated. The method was based on the proportional discrimination of trichromatic luminescence and the nonparametric and unsupervised automatic threshold selection algorithm. The macroscopic soot onset threshold in ethylene diffusion flame with three ethyl esters additions could be precisely determined. It was found that the undesirable soot onset phenomenon for ethylene diffusion flames was significantly suppressed with ethyl ester addition. The method proposed here will be useful as a reference for soot diagnostics in other flames.

Practice patterns and outcomes of hemophagocytic lymphohistiocytosis in adults: a 2-decade provincial retrospective review.

Hemophagocytic lymphohistiocytosis (HLH) is a heterogeneous, life-threatening clinical syndrome. There are scarce data on the quality of care in HLH or data comparing treatment patterns and outcomes between different triggers. We aimed to examine quality-of-care indicators and outcomes in adults with various HLH triggers. In this multi-centre retrospective cohort study of adult HLH in the province of Alberta, Canada (1999-2019), we examined quality indicators including diagnostic testing, time to diagnosis and treatment and trigger identification. We also compared treatment regimens and outcomes across HLH triggers. Logistic regression was used to identify predictors of etoposide use. Overall survival (OS) was estimated using the Kaplan-Meier method. We identified 97 patients; 66 (68%) were male. Triggers included malignancy (36%), infection (35%), autoimmune disease (21%) and idiopathic/others (8%). Specialized tests such as sCD25 (53%) and natural killer degranulation assay (19%) were under-performed, as were testing for infectious triggers. Etoposide was administered in only 33 (34%). Neutropenia, hyperbilirubinemia and hyperferritinemia, but not age, sex and comorbidities, were significant predictors of etoposide use. At median follow-up of 32 months, median OS was 18.8 months. Worse OS was seen in malignancy-associated and idiopathic HLH (log-rank P < 0.001). Our study showed low rates of specialized testing such as sCD25 and a low rate of etoposide use. Development of a standardized provincial protocol has the potential to improve quality of care in adult HLH.

Trends of outcomes and healthcare utilization following orthopaedic procedures in adults with haemophilia: A 3-decade retrospective review.

INTRODUCTION: Haemophilic arthropathy is a serious complication of haemophilia often requiring surgical intervention. It is unclear whether advances in comprehensive care are associated with a reduction in orthopaedic interventions and peri-procedural resource utilization. AIM: To determine temporal patterns of orthopaedic interventions in persons with haemophilia (PWH), and evaluate changes in healthcare utilization and outcomes. METHODS: In this Canadian multicentre retrospective cohort study, adult PWH from Northern Alberta and British Columbia who underwent orthopaedic procedures (1990-2018) were included. Temporal changes in the type of procedures, length of stay (LOS), factor utilization and outcomes were examined. RESULTS: Sixty-five patients (78% haemophilia A) underwent 102 surgeries at a median age of 46.3. Of the 46 severe PWH, 28 (61%) were on prophylaxis at time of surgery. The proportion of total knee arthroplasties (TKA) declined over time (56% 1990-1999, 51% 2000-2009, 27% 2010-2018), with a concomitant rise in ankle arthrodesis (0% 1990-1999, 18% 2000-2009, 27% 2010-2018). Over time, PWH underwent orthopaedic procedures at an older age (P = .02). There was a significant reduction in perioperative factor VIII utilization (P = .003) and median LOS (P < .0001). Major bleeds, prosthetic joint infections and thrombosis were not observed in the last decade. CONCLUSION: In the last three decades, there was a decline in the proportion of TKA, likely reflecting the impact of widespread use of tertiary prophylaxis. However, ankle arthrodesis rates increased, suggesting that higher trough levels may be required to prevent ankle arthropathy. We observed a significant reduction in LOS and factor utilization, reflecting improvements in perioperative management.

Diabetes, hepatitis C and human immunodeficiency virus influence hypertension risk differently in cohorts of haemophilia patients, veterans and the general population.

INTRODUCTION: The reasons for the high prevalence of hypertension in persons with haemophilia (PWH) are poorly understood. AIM: To examine the roles of diabetes, Hepatitis C Virus (HCV) and Human Immunodeficiency Virus (HIV) in the etiology of hypertension for PWH. METHODS: Retrospective cross-sectional design. Adult PWH (n = 691) were divided into two groups: (A) free of diabetes, HCV and HIV; (B) with diabetes and/or HCV positivity and/or HIV positivity. Each group was matched by race and age with random samples from the general population of the US (National Health and Nutrition Examination Surveys, NHANES) and outpatients at the Veterans Affairs Medical Center (VAMC) in San Diego. Generalized additive models (GAMs) were fitted for graphical analysis of hypertension risk over the lifespan. RESULTS: In Group A, PWH had the highest prevalence of hypertension compared to NHANES and VAMC, especially in young adults. In Group B, diabetes increased the risk of hypertension for all three cohorts (PWH, NHANES and VAMC), especially for PWH. In PWH, hypertension risk was also increased by HIV, in NHANES by HCV, and in VAMC by HCV and HIV. CONCLUSION: Diabetes conferred the greatest risk of hypertension for all three cohorts. However, curves of hypertension in relation to age revealed that diabetes, HCV and HIV modulated hypertension risk differently in PWH. PWH experienced a disproportionally high risk increase with diabetes. Therefore, haemophilia care should include screening for hypertension and diabetes at a young age.

Blood pressure in persons with haemophilia with a focus on haemophilia-specific risk factors.

INTRODUCTION: Persons with haemophilia (PWH) have a higher prevalence of hypertension compared to the general population, which cannot be explained entirely by the usual cardiovascular risk factors. Neutralizing antibodies (inhibitors) against clotting factors might have some relation to cardiovascular disease in PWH. However, whether inhibitors facilitate hypertension is unknown. AIM: We investigated the relationship between hypertension/blood pressure and inhibitors in PWH. Additional goals were to determine the relationships with haemophilia type, race, and viral status. METHODS: Records were extracted retrospectively for PWH (age ≥18 years) between 2003 and 2014 from four Hemophilia Treatment Centers in North America and included demographics, weight, height, haemophilia type/severity, HCV and HIV infection status, hypertension, use of anti-hypertensive medications, and inhibitor status. We fitted semiparametric generalized additive models (GAMs) to describe adjusted curves of blood pressure (BP) against age. RESULTS: Among 691 PWH, 534 had haemophilia A and 157 had haemophilia B, with a median age of 39 years (range 18 to 79). Forty-four PWH (6.5%) had a history of inhibitors, without evidence for a higher prevalence of hypertension or higher BP. A higher prevalence of hypertension and higher BP were noted for haemophilia A (vs. haemophilia B), coinfection with HCV/HIV (vs. uninfected), or moderate haemophilia (vs. severe haemophilia). CONCLUSION: While there was no signal to suggest that a history of inhibitors is associated with hypertension, differences based on haemophilia type, severity, and viral infection status were identified, encouraging prospective investigations to better delineate haemophilia-specific risk factors for hypertension.

Risk of diabetes in haemophilia patients compared to clinic and non-clinic control cohorts.

INTRODUCTION: Ageing patients with haemophilia (PWH) develop cardiovascular risk factors impacting care. Little is known about the prevalence of diabetes in PWH and its relation to other comorbidities. AIM: To examine the risk of diabetes for adult PWH compared to men from the general United States population (National Health and Nutrition Examination Surveys [NHANES]) and outpatients attending a Veterans Affairs Medical Center (VAMC) clinic. METHODS: Retrospective cross-sectional design. PWH from four haemophilia centres (n = 690) were matched with random samples from NHANES and VAMC. Diabetes (yes/no) was the outcome, while age, body mass index (BMI), race and Hepatitis C (HCV; by serology) and human immunodeficiency virus (HIV) positivity were covariates. We fitted semiparametric generalized additive models (GAMs) in order to compare diabetes risk between cohorts. RESULTS: Younger PWH were at lower risk of diabetes than NHANES or VAMC subjects irrespective of BMI. However, the risk of diabetes rose in older PWH and was closely associated with HCV. For HCV-negative subjects, the risk of diabetes was considerably lower for PWH than NHANES and VAMC subjects. The difference persisted after controlling for BMI and age, indicating that the low risk of diabetes in PWH cannot be explained by lean body mass alone. CONCLUSION: Since many ageing PWH are HCV positive and therefore at heightened risk for diabetes, it is important to incorporate diabetes screening into care algorithms in Haemophilia Treatment Centers, especially since PWH are not always followed in primary care clinics.

Validation of the HScore and the HLH-2004 diagnostic criteria for the diagnosis of hemophagocytic lymphohistiocytosis in a multicenter cohort.

Timely diagnosis of hemophagocytic lymphohistiocytosis (HLH) is critical and relies on clinical judgment. The HLH-2004 criteria are commonly used diagnostic criteria, whereas HScore was recently developed for reactive HLH. OBJECTIVE: In this external validation study, we sought to compare the diagnostic accuracy of the HLH-2004 criteria and HScore and identify optimal cutoffs stratified by underlying etiology. METHODS: In this retrospective cohort of all hospitalized adults in Alberta, Canada, (1999-2019) who had ferritin >500 ng/ml and underwent either biopsies or soluble CD25 testing, we calculated the diagnostic accuracy of HLH-2004 and HScore for the overall population and different etiologies. RESULTS: Of 916 patients, 98 (11%) had HLH. HLH-2004 criteria ≥5 predicted HLH with a sensitivity of 91%, specificity of 93%, positive predictive value of 90%, and negative predictive value of 94% (c-statistic 92%). HScore ≥169 predicted HLH with better sensitivity (96%) but reduced specificity (71%), whereas the optimal cutoff ≥200 performed comparably to HLH-2004. HLH-2004 criteria outperformed HScore in most etiologies, whereas HScore improved sensitivity in inflammatory/autoimmune-HLH. The optimal cutoff of HScore was higher in hematopoietic cell transplant due to higher prevalence of fevers and cytopenias. CONCLUSION: HLH-2004 criteria and HScore demonstrated excellent discriminatory power in identifying HLH. HScore may improve diagnostic accuracy in autoimmune-HLH.

Preparation and Evaluation of Novel Supersaturated Solid Dispersion of Magnolol : Theme: Advancements in Amorphous Solid Dispersions to Improve Bioavailability.

This article aimed to design a new type of supersaturated solid dispersion (NS-SD) loaded with Magnolol (Mag) to raise the oral bioavailability in rats. In the light of the solubility parameters, phase solubility experiments, inhibition precipitation experiment, and in vitro release experiment, Plasdone-630 (PS-630) was selected as the optimum carrier. In addition, Mag-NS-SD was prepared by adding Monoglyceride (MG) and Lecithin High Potency (LHP) into the Mag-S-SD (Mag:PS-630 = 1:3), so as to reduce the dosage of carrier and improve the release rate. Using central composite design of response surface method, the prescription was further optimized. As the optimized condition was Mag:PS-630: MG: LHP = 1:3:0.8:0.266, the drug release rate was the fastest. Besides, after 45 min, the release rate was nearly 100%. The constructed Mag-S-SD and Mag-NS-SD were characterized by powder X-ray diffraction and infrared absorption spectrum. The XRD patterns of Mag-S-SD and Mag-NS-SD indicated that all APIs were amorphous. The IR spectra of Mag-S-SD and Mag-NS-SD demonstrated the existence of hydrogen bonding in the systems. Furthermore, in vivo pharmacokinetic study in rats revealed that compared with Mag and Mag-S-SD, Mag-NS-SD significantly increased the bioavailability (the relative bioavailability was 213.69% and 142.37%, separately). In this study, Mag-NS-SD was successfully prepared, which could improve the oral bioavailability and may increase the clinical application.

All-cause mortality and causes of death in persons with haemophilia: A systematic review and meta-analysis.

INTRODUCTION: Improvements in haemophilia treatment over the last decades resulted in increased life expectancy in persons with haemophilia (PWH). AIM: We conducted a systematic review and meta-analysis to examine all-cause mortality and causes of death among PWH. METHODS: We systematically searched EMBASE, MEDLINE, Web of Science, CINAHL and Cochrane central register of controlled trials from inception through March 15, 2021. Studies that reported a mortality estimate of PWH compared with the general population and/or reported causes of death were included. Random-effects meta-analysis with inverse variance method was used to obtain pooled estimates. We stratified the analysis by the year of cohort entry (before 2000 vs after 2000). RESULT: Of the 4769 studies identified, 52 met the eligibility criteria. The pooled all-cause standardized mortality ratio (SMR) from 9 studies in PWH was 1.93 (95% CI 1.38-2.70; I2 = 97%). The pooled SMRs before and after the year 2000 were 2.40 (95% CI 1.92-3.00; I2 = 87%) and 1.20 (95% CI 1.03-1.40; I2 = 62%), respectively. Before the year 2000, 31.2% deaths occurred due to HIV followed by haemorrhage (26.0%), cardiovascular disease (18.2%), liver disease (9.0%), and cancer (8.9%). Fewer (13.9%) deaths were attributable to HIV after the year 2000 with the proportion of deaths due to haemorrhage remaining unchanged. CONCLUSION: With treatment advances, mortality in PWH has declined over the last few decades approaching that of the general population. However, haemorrhage remains a leading cause of death requiring further attention.

Factor product utilization and health outcomes in patients with haemophilia A and B on extended half-life concentrates: A Canadian observational study of real-world outcomes.

INTRODUCTION: Recombinant factors VIII and IX Fc (rFVIIIFc/rFIXFc) became available in Canada in 2016 and were the only extended half-life (EHL) factor concentrates available in Canada until 2018. OBJECTIVES: We aim to describe the change in product utilization in Canadians who switched to rFVIIIFc/rFIXFc. METHODS: This prospective and retrospective cohort study enrolled males aged ≥6 years with moderate or severe haemophilia who switched to rFVIIIFc/rFIXFc and those who remained on standard half-life (SHL) between 2016 and 2018. Factor utilization and annualized bleeding rates (ABR) were collected at baseline, 1-year and 2-years. Due to low prospective enrolment (n = 25 switchers), prospective and retrospective data were pooled. RESULTS: 125 switchers (93 rFVIIIFc, 32 rFIXFc) and 33 non-switchers were included. The median age was 17 (rFVIIIFc) and 38 years (rFIXFc). Prior to switch, over 80% were on prophylaxis. There was a statistically significant reduction in the prescribed weekly prophylactic dose after the switch to rFVIIIFc/rFIXFc for all age groups, with a corresponding reduction (15-16%) in actual annualized FIX utilization in switchers (combined adults and children) to rFIXFc, and a smaller non-significant reduction in actual annualized FVIIII utilization (7%) in children who switched to rFVIIIFc. A significant reduction in the median ABR was only observed in children who switched to rFVIIIFc, but not in adults who switched to rFVIIIFc or rFIXFc. CONCLUSION: Switching from SHL to EHL products led to a small reduction in factor utilization, while preserving a low ABR in children and adults with haemophilia. Further patient-reported outcomes data will further elucidate the role of EHL in the haemophilia landscape.

The Clinical Conundrum of Managing Ischemic Stroke in Patients with Immune Thrombocytopenia.

Guidelines are lacking for management of acute ischemic stroke and stroke prevention in patients with immune thrombocytopenia (ITP). Our aim is to highlight the dilemma inherent in managing patients with both significant bleeding and thrombotic risk factors. In this review, we present two patients with history of ITP who presented with acute ischemic stroke and received tissue plasminogen activator (tPA) and endovascular thrombectomy (EVT), a rare management strategy in this patient population. In addition, we identified 27 case reports of ischemic stroke in patients with ITP; none of them received tPA or EVT. Furthermore, there are 92 patients with significant thrombocytopenia with no available data regarding the cause of thrombocytopenia, who were acutely treated with tPA or EVT. Conclusive evidence cannot be determined based on these limited number of cases. Future multicenter prospective cohort studies in patients with ITP are needed to provide better evidence-based treatment plans. At present, treatment of acute ischemic stroke in patients with ITP requires close collaboration between hematology and vascular neurology experts to find a balance between the benefit and risk of hemorrhagic complications.

A Novel Carbon Dots/Thermo-Sensitive In Situ Gel for a Composite Ocular Drug Delivery System: Characterization, Ex-Vivo Imaging, and In Vivo Evaluation.

We developed a potential composite ocular drug delivery system for the topical administration of diclofenac sodium (DS). The novel carbon dot CDC-HP was synthesized by the pyrolysis of hyaluronic acid and carboxymethyl chitosan through a one-step hydrothermal method and then embedded in a thermosensitive in situ gel of poloxamer 407 and poloxamer 188 through swelling loading. The physicochemical characteristics of these carbon dots were investigated. The results of the in vitro release test showed that this composite ocular drug delivery system (DS-CDC-HP-Gel) exhibited sustained release for 12 h. The study of the ex vivo fluorescence distribution in ocular tissues showed that it could be used for bioimaging and tracing in ocular tissues and prolong precorneal retention. Elimination profiles in tears corresponded to the study of ex vivo fluorescence imaging. The area under the curve of DS in the aqueous humor in the DS-CDC-HP-Gel group was 3.45-fold that in the DS eye drops group, indicating a longer precorneal retention time. DS-CDC-HP with a positive charge and combined with a thermosensitive in situ gel might strengthen adherence to the corneal surface and prolong the ocular surface retention time to improve the bioavailability. This composite ocular delivery system possesses potential applications in ocular imaging and drug delivery.