Increased In Vivo Exposure of N-(4-Hydroxyphenyl) Retinamide (4-HPR) to Achieve Plasma Concentrations Effective against Dengue Virus.

N-(4-hydroxyphenyl) retinamide (4-HPR, or fenretinide) has promising in vitro and in vivo antiviral activity against a range of flaviviruses and an established safety record, but there are challenges to its clinical use. This study evaluated the in vivo exposure profile of a 4-HPR dosage regime previously shown to be effective in a mouse model of severe dengue virus (DENV) infection, comparing it to an existing formulation for human clinical use for other indications and developed/characterised self-emulsifying lipid-based formulations of 4-HPR to enhance 4-HPR in vivo exposure. Pharmacokinetic (PK) analysis comprising single-dose oral and IV plasma concentration-time profiles was performed in mice; equilibrium solubility testing of 4-HPR in a range of lipids, surfactants and cosolvents was used to inform formulation approaches, with lead formulation candidates digested in vitro to analyse solubilisation/precipitation prior to in vivo testing. PK analysis suggested that effective plasma concentrations could be achieved with the clinical formulation, while novel lipid-based formulations achieved > 3-fold improvement. Additionally, 4-HPR exposure was found to be limited by both solubility and first-pass intestinal elimination but could be improved through inhibition of cytochrome P450 (CYP) metabolism. Simulated exposure profiles suggest that a b.i.d dosage regime is likely to maintain 4-HPR above the minimum effective plasma concentration for anti-DENV activity using the clinical formulation, with new formulations/CYP inhibition viable options to increase exposure in the future.

Antivirals that target the host IMPα/ß1-virus interface.

Although transport into the nucleus mediated by the importin (IMP) α/ß1-heterodimer is central to viral infection, small molecule inhibitors of IMPα/ß1-dependent nuclear import have only been described and shown to have antiviral activity in the last decade. Their robust antiviral activity is due to the strong reliance of many different viruses, including RNA viruses such as human immunodeficiency virus-1 (HIV-1), dengue (DENV), and Zika (ZIKV), on the IMPα/ß1-virus interface. High-throughput compound screens have identified many agents that specifically target this interface. Of these, agents targeting IMPα/ß1 directly include the FDA-approved macrocyclic lactone ivermectin, which has documented broad-spectrum activity against a whole range of viruses, including HIV-1, DENV1-4, ZIKV, West Nile virus (WNV), Venezuelan equine encephalitis virus, chikungunya, and most recently, SARS-CoV-2 (COVID-19). Ivermectin has thus far been tested in Phase III human clinical trials for DENV, while there are currently close to 80 trials in progress worldwide for SARS-CoV-2; preliminary results for randomised clinical trials (RCTs) as well as observational/retrospective studies are consistent with ivermectin affording clinical benefit. Agents that target the viral component of the IMPα/ß1-virus interface include N-(4-hydroxyphenyl) retinamide (4-HPR), which specifically targets DENV/ZIKV/WNV non-structural protein 5 (NS5). 4-HPR has been shown to be a potent inhibitor of infection by DENV1-4, including in an antibody-dependent enhanced animal challenge model, as well as ZIKV, with Phase II clinical challenge trials planned. The results from rigorous RCTs will help determine the therapeutic potential of the IMPα/ß1-virus interface as a target for antiviral development.

The association between early neurological deterioration and whole blood purine concentration during acute stroke.

BACKGROUND: Early neurological deterioration (END) is common after stroke. Prediction could identify patients requiring additional monitoring and intervention. Purines, breakdown products of adenosine triphosphate which accumulate during acute hypoxia, may reflect the subclinical presence of vulnerable tissue. We considered whether whole blood purine concentration (WBPC) measurements during acute stroke were associated with subsequent END. METHODS: Patients within 4.5 h of stroke onset underwent point-of-care finger-prick measurement of WBPC and blinded assessment of symptom severity using the National Institutes of Health Stroke Scale (NIHSS). END was defined as an NIHSS increase ≥2 points at 24-36 h compared to baseline. RESULTS: 15/152 (9.8%) patients experienced END with a median [IQR] NIHSS increase of 4 [2-7] points. There were no strong associations between END and baseline NIHSS, clinical stroke subtype, thrombolytic therapy, physiological characteristics or time to assay. The median [IQR] WBPC concentration (uM) was higher before the occurrence of END but without statistical significance (7.21 [4.77-10.65] versus 4.83 [3.00-9.02]; p = 0.1). Above a WBPC threshold of 6.05uM, the risk of END was significantly greater (odds ratio 3.7 (95% CI 1.1-12.4); p = 0.03). CONCLUSION: Although the study lacked statistical power, early WBPC measurement could be a convenient biomarker for identifying acute stroke patients at risk of END, but further evaluation is required.

Inhibitors of nuclear transport.

Central to eukaryotic cell function, transport into and out of the nucleus is largely mediated by members of the Importin (IMP) superfamily of transporters of α- and ß-types. The first inhibitor of nuclear transport, leptomycin B (LMB), was shown to be a specific inhibitor of the IMPß homologue Exportin 1 (EXP1) almost 20 years ago, but it has only been in the last five or so years that new inhibitors of nuclear export as well as import have been identified and characterised. Of utility in biological research, these inhibitors include those that target-specific EXPs/IMPs, with accompanying toxicity profiles, as well as agents that specifically target particular nuclear import cargoes. Both types of inhibitors have begun to be tested in preclinical/clinical studies, with particular focus on limiting various types of cancer or treating viral infection, and the most advanced agent targeting EXP1 (Selinexor) has progressed successfully through >40 clinical trials for a range of high-grade cancers and is approaching FDA approval for a number of indications. Selectively inhibiting the nucleocytoplasmic trafficking of specific proteins of interest remains a challenge, but progress in the area of the host-pathogen interface holds promise for the future.

A Systematic Review and Meta-Analysis of Molecular Biomarkers Associated with Early Neurological Deterioration Following Acute Stroke.

BACKGROUND: Early neurological deterioration (END) following acute stroke is associated with poorer long-term outcomes. Identification of patients at risk could assist early monitoring and treatment decisions. This review summarised the evidence describing non-radiological biomarkers for END. SUMMARY: Electronic searches from January 1990 to March 2017 identified studies reporting a blood/cerebrospinal fluid (CSF)/urine biomarker measurement within 24 h of acute stroke and at least 2 serial assessments of clinical neurological status (< 24 h and < 7 days). Out of 12,895 citations, 82 studies were included, mostly focusing on ischaemic stroke. Using higher neurological thresholds, the n-weighted END incidence for ischaemic stroke was 11.9% (95% CI 11.4-12.4%) and 18.6% (17.9-19.2%) for lower thresholds. Incidence decreased with advancing study publication year (Pearson r-squared 0.23 and 0.15 for higher and lower threshold studies). After classification into 3 broad categories, meta-analysis showed that biomarkers associated with increased END risk (n; fixed-effects mean difference; 95% CI) were "metabolic" (glucose [n = 9,481; 0.90 mmol/L; 0.74-1.06], glycosylated haemoglobin [n = 3,146; 0.33%; 0.19-0.46], low-density lipoprotein [n = 4,839; 0.13 mmol/L; 0.06-0.21], total cholesterol [n = 4,762; 0.21 mmol/L; 0.11-0.31], triglycerides [n = 4,820; 0.11 mmol/L; 0.06-0.17], urea [n = 1,351; 0.55 mmol/L; 0.14-0.96], decreasing albumin [n = 513; 0.33 g/dL; 0.05-0.61]); "inflammatory and excitotoxic" (plasma glutamate [n = 688; 60.13 µmol/L; 50.04-70.22], CSF glutamate [n = 369; 7.50 µmol/L; 6.76-8.23], homocysteine [n = 824; 2.15 µmol/L; 0.68-3.61], leucocytes [n = 3,766; 0.54 × 109/L; 0.34-0.74], high-sensitivity C-reactive protein [n = 1,707; 3.79 mg/L; 1.23-6.35]); and "coagulation/haematological" (fibrinogen [n = 3,132; 0.32 g/L; 0.25-0.40]; decreasing haemoglobin [n = 3,586; 2.38 g/L; 0.15-4.60]). Key Messages: Declining incidence of END may represent improving care standards; however, it remains a frequent occurrence. Although statistical associations exist between biomarkers and an increased risk of END, the most promising still need prospective evaluation to determine their additional value relative to baseline radiological and clinical characteristics.

Nucleocytoplasmic Trafficking of Dengue Non-structural Protein 5 as a Target for Antivirals.

Signal-dependent movement of proteins into and out of the nucleus through the importin superfamily of transporters is central to the replication of many viruses in infected cells, including RNA viruses such as the flavivirus Dengue virus (DENV). DENV non-structural protein 5 (NS5) traffics into and out of the host cell nucleus/nucleolus, being observed in the nucleus, although to differing extents, very early in infection in the case of all 4 DENV serotypes; with results from both reverse genetics and inhibitor studies indicating that this trafficking is critical to DENV infection. Knowledge of the transporters and targeting signals responsible for nuclear trafficking of NS5 has enabled inhibitors of DENV NS5 nuclear import to be identified using a novel screening/counterscreen approach. N-(4-hydroxyphenyl) retinamide (4-HPR) is of particular interest as a specific, non-toxic inhibitor able to protect against infection by all four serotypes of DENV, as well as the severe, antibody-enhanced form of DENV infection, in a lethal mouse model. Since 4-HPR can also inhibit DENV-related flaviviruses of medical significance such as West Nile Virus and Zika virus, it is of great interest for future commercialisation. Targeting nucleocytoplasmic trafficking of flavivirus proteins promises to be a powerful strategy to counter flaviviruses, for which the development of protective vaccines has thus far proven problematic.

Correction to: Raised Serum IL-8 Levels Are Associated with Excessive Fatigue in Female Carriers of X-Linked Chronic Granulomatous Disease in the UK.

The original version of the article, "Raised Serum IL-8 Levels Are Associated with Excessive Fatigue in Female Carriers of X-Linked Chronic Granulomatous Disease in the UK" incorrectly listed the name of the fourth author as Fai W. Ng. The correct spelling of the author's name is WF Ng.

Widening interest, widening participation: factors influencing school students' aspirations to study medicine.

BACKGROUND: Under-representation of some socio-economic groups in medicine is rooted in under-representation of those groups in applications to medical school. This study aimed to explore what may deter school-age children from applying to study medicine. METHODS: Workshops were undertaken with school students aged 16-17 years ('Year 12', n = 122 across three workshops) and 13-14 years ('Year 9', n = 295 across three workshops). Workshops used a variety of methods to identify and discuss participants' perceptions of medicine, medical school and the application process. Year 12 workshops focused on applications and medical school, while Year 9 took a broader approach reflecting their relative distance from applying. Subsequent workshops were informed by the findings of earlier ones. RESULTS: The main finding was that potential applicants had limited knowledge about medicine and medical school in several areas. Older students would benefit from accessible information about medical degrees and application processes, access to work experience opportunities and personal contact with medical students and junior doctors, particularly those from a similar background. Younger students demonstrated a lack of awareness of the breadth of medical careers and a limited understanding of what medicine encompasses. Many Year 9 students were attracted by elements of practice which they did not associate with medicine, such as 'talking to people with mental health problems'. An exercise addressing this elicited an increase in their interest in medicine. These issues were identified by participants as being more marked for those without knowledgeable support at home or school. It was apparent that school teachers may not be equipped to fill these knowledge gaps. CONCLUSION: Gaps in knowledge and support may reflect the importance of 'social capital' in facilitating access to medical school. Medical schools could act as hubs to introduce students to resources which are essential for widening participation. Outreach and support to schools may ensure that fundamental knowledge gaps are equitably addressed for all prospective applicants. More generally, a focus on medicine which under-emphasises aspects of medical practice involving communication may deter some students and have longer term impact on recruitment to careers including general practice and psychiatry.

Agreement between ambulance and hospital records for information promoting urgent stroke treatment decisions.

OBJECTIVE: Rapid decision-making during acute stroke care can improve outcomes. We wished to assess whether crucial information to facilitate decisions is routinely collected by emergency practitioners before hospital admission. MATERIALS AND METHODS: We examined whether ambulance records contained information relevant to a thrombolysis treatment decision for consecutive stroke admissions to three emergency departments in England between 14 May 2012 and 10 June 2013. RESULTS: In all, 424 of 544 (78%) records included a paramedic diagnosis of stroke. Twice as many hospital records contained a symptom onset time/last known to be well time, but there was 82% agreement within 1 h when a prehospital time was also recorded. This was more likely for younger patients. Documentation of medication history was infrequent (12%), particularly for anticoagulant status (6%). When compared with hospital documentation, paramedics recorded a history of diabetes for 38/49 (78%), previous stroke 44/69 (64%), hypertension 71/140 (51%) and atrial fibrillation 19/64 (30%). CONCLUSION: In a retrospective cohort of stroke patients admitted by emergency ambulance, standard practice did not consistently result in prehospital documentation of information that could promote rapid treatment decisions. Training emergency practitioners and/or providing clinical protocols could facilitate early stroke treatment decisions, but prehospital information availability is likely to be a limiting factor.