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An orthogonal, noncovalent approach to direct the assembly of higher-order DNA origami nanostructures is described. By incorporating perfluorinated tags into the edges of DNA origami tiles we control their hierarchical assembly via fluorous-directed recognition. When we combine this approach with Watson-Crick base-pairing we form discrete dimeric constructs in significantly higher yield (8x) than when either molecular recognition method is used in isolation. This integrated "catch-and-latch" approach, which combines the strength and mobility of the fluorous effect with the specificity of base-pairing, provides an additional toolset for DNA nanotechnology, one that enables increased assembly efficiency while requiring significantly fewer DNA sequences. As a result, our integration of fluorous-directed assembly into origami systems represents a cheap, atom-efficient means to produce discrete superstructures.

Objectives: Sexually transmitted infections are a prevalent global health care problem. Treatment guidelines have recently been updated as a result of antimicrobial resistance and public health trends. The aim of the study was to assess the appropriateness of empirical antibiotic therapy prescribed for cervicitis and urethritis in the emergency department. Methods: We designed a retrospective observational cohort study. We included adult patients with suspected cervicitis or urethritis who attended the emergency department of a tertiary hospital in 2020. We excluded patients with suspected pelvic inflammatory disease, pregnancy or prostatitis and those requiring admission to hospital. Appropriateness of empirical antibiotic therapy was evaluated taking into account 4 aspects: indication, dosing, duration of therapy, and route of administration. Data were obtained from the electronic medical record, the electronic prescription program, and the discharge summary. Results: The study population comprised 176 patients; mean age was 28.9 years (SD = 7.7), and 90.9% were men. The most prescribed treatment was the combination of ceftriaxone and azithromycin (83.0%). Treatment was inappropriate in 71.6% of patients. A total of 159 drug errors were recorded. The most frequent cause was undertreatment (36.4%) related to underdosing (46.5%), particularly with regard to ceftriaxone. The percentage of errors was 11.9% for indication, 84.9% for dosing, 3.1% for duration, and 0% for route of administration. Conclusions: A high percentage of patients who attended the emergency department for suspected cervicitis or urethritis received an inappropriate empirical antibiotic regimen. The main reason was undertreatment due to underdosing.

The global increase in antimicrobial-resistant infections means that there is a need to develop new antimicrobial molecules and strategies to combat the issue. Aurodox is a linear polyketide natural product that is produced by Streptomyces goldiniensis, yet little is known about aurodox biosynthesis or the nature of the biosynthetic gene cluster (BGC) that encodes its production. To gain a deeper understanding of aurodox biosynthesis by S. goldiniensis, the whole genome of the organism was sequenced, revealing the presence of an 87 kb hybrid polyketide synthase/non-ribosomal peptide synthetase (PKS/NRPS) BGC. The aurodox BGC shares significant homology with the kirromycin BGC from S. collinus T? 365. However, the genetic organization of the BGC differs significantly. The candidate aurodox gene cluster was cloned and expressed in a heterologous host to demonstrate that it was responsible for aurodox biosynthesis and disruption of the primary PKS gene (aurAI) abolished aurodox production. These data supported a model whereby the initial core biosynthetic reactions involved in aurodox biosynthesis followed that of kirromycin. Cloning aurM∗ from S. goldiniensis and expressing this in the kirromycin producer S. collinus T? 365 enabled methylation of the pyridone group, suggesting this is the last step in biosynthesis. This methylation step is also sufficient to confer the unique type III secretion system inhibitory properties to aurodox. IMPORTANCE Enterohemorrhagic Escherichia coli (EHEC) is a significant global pathogen for which traditional antibiotic treatment is not recommended. Aurodox inhibits the ability of EHEC to establish infection in the host gut through the specific targeting of the type III secretion system while circumventing the induction of toxin production associated with traditional antibiotics. These properties suggest aurodox could be a promising anti-virulence compound for EHEC, which merits further investigation. Here, we characterized the aurodox biosynthetic gene cluster from Streptomyces goldiniensis and established the key enzymatic steps of aurodox biosynthesis that give rise to the unique anti-virulence activity. These data provide the basis for future chemical and genetic approaches to produce aurodox derivatives with increased efficacy and the potential to engineer novel elfamycins.

A modular approach to prepare tri- and tetracyclic carbazoles by a sequential [3 + 2]heteroannulation is described. First, optimization of Pd-catalyzed Buchwald-Hartwig amination followed by C/N-arylation in a one-pot process is established. Second, mechanistic analyses identified the origins of chemo- and regioselective sequential control of both bond-forming steps. Finally, the substrate scope is demonstrated by the preparation of a range of tri- and tetracyclic carbazoles, including expedient access to several natural products and anti-cancer agents.

Worldwide organisations advocate standardising the management of intravenous drugs as an essential strategy to increase safety in paediatric healthcare settings. Intravenous administration is a route associated with some potential complications. Many adverse events are related to the use of intravenous medications, and the great variability in their handling and preparation represents an added risk that jeopardises the safety of children.To standardise the dilutions of intravenous drugs most commonly administered to Spanish hospitalised paediatric and neonatal patients.The process leading to the standardisation of concentrations was undertaken following a two-round modified Delphi procedure. The consensus included the most common drugs administered by continuous or intermittent intravenous infusion to hospitalised and/or critically ill paediatric patients.For paediatric patients, the proposal included a total of 102 drugs (45 continuous infusion and 59 intermittent infusion), with 192 concentrations to be standardised. The final consensus included 101 drugs (99%), of which 44 were continuous infusion and 59 intermittent infusion; 160 concentrations were standardised (72.7%). For neonates, the initial proposal included 80 drugs (38 continuous infusion and 43 intermittent infusion), with 189 concentrations to be standardised. The final consensus included 80 drugs (100%), of which 38 were continuous infusion and 43 were intermittent infusion; 120 concentrations were standardised (49.2%).This proposal showed that standardisation is a feasible approach that can be reached by other healthcare institutions. It can be used in other centres and contribute in the future to unifying paediatric clinical practice.

The global increase in antimicrobial-resistant infections means that there is a need to develop new antimicrobial molecules and strategies to combat the issue. Aurodox is a linear polyketide natural product that is produced by Streptomyces goldiniensis, yet little is known about aurodox biosynthesis or the nature of the biosynthetic gene cluster (BGC) that encodes its production. To gain a deeper understanding of aurodox biosynthesis by S. goldiniensis, the whole genome of the organism was sequenced, revealing the presence of an 87 kb hybrid Polyketide Synthase/Non-Ribosomal Peptide Synthetase (PKS/NRPS) BGC. The aurodox BGC shares significant homology with the kirromycin BGC from S. collinus Tϋ 365; however, the genetic organisation of the BGC differs significantly. The candidate aurodox gene cluster was cloned and expressed in a heterologous host to demonstrate that it was responsible for aurodox biosynthesis and disruption of the primary PKS gene (aurAI) abolished aurodox production. These data support a model whereby the initial core biosynthetic reactions involved in aurodox biosynthesis follow that of kirromycin. Cloning aurM* from S. goldiniensis and expressing this in the kirromycin producer S. collinus Tϋ 365 enabled methylation of the pyridone group, suggesting this is the last step in biosynthesis. This methylation step is also sufficient to confer the unique Type III Secretion System inhibitory properties to aurodox.ImportanceEnterohaemorrhagic Escherichia coli (EHEC) is a significant global pathogen for which traditional antibiotic treatment is not recommended. Aurodox inhibits the ability of EHEC to establish infection in the host gut through the specific targeting of the Type III Secretion System, whilst circumventing the induction of toxin production associated with traditional antibiotics. These properties suggest aurodox could be a promising anti-virulence compound for EHEC, which merits further investigation. Here, we have characterised the aurodox biosynthetic gene cluster from Streptomyces goldiniensis and have established the key enzymatic steps of aurodox biosynthesis that give rise to the unique anti-virulence activity. These data provide the basis for future chemical and genetic approaches to produce aurodox derivatives with increased efficacy and the potential to engineer novel elfamycins.

A modular approach to prepare tri- and tetracyclic carbazoles by a sequential [3+2]heteroannulation is described. First, op-timization of a Pd-catalyzed Buchwald-Hartwig amination followed by C/N-arylation in a one-pot process is established. Second, mechanistic analyses identified the origins of chemo- and regioselective sequential control of both bond-forming steps. Finally, the substrate scope is demonstrated by the preparation of a range of tri- and tetracyclic carbazoles, including expedient access to several natural products and anti-cancer agents.

Manipulating alternative RNA splicing events with small molecules is emerging as a viable mechanism for the development of therapeutics. A salient challenge in the field is understanding the molecular determinants defining the selectivity of splice-switching events and their mechanisms of action. In this review, the current state-of-the-art in splice-switching small molecules is described. Three examples of splice-switching small molecules are presented, and the differences in their modes of action compared.

Background and importance Cancer patients are a vulnerable population for SAR-CoV-2 infection Aim and objectives The aim of our study was to describe the epidemiology and clinical course of patients with cancer infected with SARS-Cov-2, attending hospital Material and methods A retrospective observational study was conducted in cancer patients attending a tertiary hospital for SARS-CoV-2 infection during the period 3 January 2020 to 31 May 2020 Demographic and clinical variables were analysed: comorbidities, tumour diagnosis, tumour stage and whether they had received anticancer treatment in the last month (active treatment) The clinical course was evaluated by hospital admission, pneumonia, oxygen therapy requirements, the development of acute respiratory distress syndrome (ARDS), admission to ICU, mortality rate and mortality rate

Background and importance Identification of the angiotensin converting enzyme (ACE2) as a target of the SARS-CoV-2 virus raises questions about a possible change in the clinical course of this infection associated with inhibitors of the renin-angiotensin-aldosterone system (RAAS) Furthermore, high blood pressure is considered a risk factor for COVID-19 Aim and objectives To characterise the clinical course in hypertensive patients admitted for COVID-19 and to determine if treatment with RAAS inhibitors, age and additional comorbidities may be related to mortality and development of acute respiratory distress syndrome (ARDS) Material and methods A single centre, observational, retrospective study was conducted Inclusion criteria were: diagnosis of hypertension, hospital admission for COVID-19 between 1 March and 24 March 2020 Demographic, clinical and analytical variables were recorded Clinical course was evaluated by: development of bilateral pneumonia, ARDS, length of stay and mortality End of follow-up was 10 October 2020 To evaluate the possible influence of factors on evolution, binary logistic regression was performed using the STATA-IC14 programme Quantitative dependent variables were transformed into dichotomous variables Statistical significance was defined as p20 mg/dL and 11 7% D-dimer >1200 ng/mL During the hospital stay, 91 9% of patients required oxygen therapy, 76 4% developed bilateral pneumonia, 91 9% required oxygen therapy, 47 5% developed ARDS and 33 6% died Median hospital stay was 15 days (IQR 9-24) Use of RAAS inhibitors was not linked to changes in mortality or development of ARDS (p>0 05) Risk factors associated with mortality were: additional cardiovascular diseases (OR=2 10;p=0 000) and older age (OR=1 05;p=0 000) Regarding ARDS, we found an association with obesity (OR=1 77;p=0 013), diabetes mellitus (OR=1 84;p=0 001) and age (OR=1 02;p=0 010) Hospital stay >14 days was significantly longer in advanced age (OR=1 02;p=0 022) and if chronic kidney disease was present (OR=1 73, p=0 043) Conclusion and relevance Antihypertensive treatment with RAAS inhibitors did not seem to be linked to the risk of worse evolution of COVID-19 Advanced age and additional cardiovascular disease appeared to be associated with higher mortality in hypertensive patients

Background: We report the long-term outcomes, changes in laboratory parameters, the incidence of secondary nosocomial infections and treatment cost of a Spanish cohort of patients with severe COVID-19 that received tocilizumab (TCZ). Methods: Retrospective cohort of PCR confirmed adult patients who received TCZ from March 1 to 24, 2020 in a tertiary hospital was analyzed. Patients were followed up until 10 May 2020. Results: We included 162 patients (median age 64 years; 70.4% male). At time of TCZ administration, 48.1% of patients were on invasive mechanical ventilation (IMV). Over a median follow-up of 53 days, 46.9% of patients were discharge in good conditions and 19.8% were still hospitalized. The overall mortality was 33.3%, being higher in patients on IMV than those who did not (46.2% vs 26.7%, P

Objectives The GETAFIX trial will test the hypothesis that favipiravir is a more effective treatment for COVID-19 infection in patients who have early stage disease, compared to current standard of care. This study will also provide an important opportunity to investigate the safety and tolerability of favipiravir, the pharmacokinetic and pharmacodynamic profile of this drug and mechanisms of resistance in the context of COVID-19 infection, as well as the effect of favipiravir on hospitalisation duration and the post COVID-19 health and psycho-social wellbeing of patients recruited to the study. Trial design GETAFIX is an open label, parallel group, two arm phase II/III randomised trial with 1:1 treatment allocation ratio. Patients will be randomised to one of two arms and the primary endpoint will assess the superiority of favipiravir plus standard treatment compared to standard treatment alone. Participants This trial will recruit adult patients with confirmed positive valid COVID-19 test, who are not pregnant or breastfeeding and have no prior major co-morbidities. This is a multi-centre trial, patients will be recruited from in-patients and outpatients from three Glasgow hospitals: Royal Alexandra Hospital; Queen Elizabeth University Hospital; and the Glasgow Royal Infirmary. Patients must meet all of the following criteria: 1. Age 16 or over at time of consent 2. Exhibiting symptoms associated with COVID-19 3. Positive for SARS-CoV-2 on valid COVID-19 test 4. Point 1, 2, 3, or 4 on the WHO COVID-19 ordinal severity scale at time of randomisation. (Asymptomatic with positive valid COVID-19 test, Symptomatic Independent, Symptomatic assistance needed, Hospitalized, with no oxygen therapy) 5. Have >=10% risk of death should they be admitted to hospital as defined by the ISARIC4C risk index: https://isaric4c.net/risk 6. Able to provide written informed consent 7. Negative pregnancy test (women of childbearing potential*) 8. Able to swallow oral medication Patients will be excluded from the trial if they meet any of the following criteria: 1. Renal impairment requiring, or likely to require, dialysis or haemofiltration 2. Pregnant or breastfeeding 3. Of child bearing potential (women), or with female partners of child bearing potential (men) who do not agree to use adequate contraceptive measures for the duration of the study and for 3 months after the completion of study treatment 4. History of hereditary xanthinuria 5. Other patients judged unsuitable by the Principal Investigator or sub-Investigator 6. Known hypersensitivity to favipiravir, its metabolites or any excipients 7. Severe co-morbidities including: patients with severe hepatic impairment, defined as: • greater than Child-Pugh grade A • AST or ALT > 5 x ULN • AST or ALT >3 x ULN and Total Bilirubin > 2xULN 8. More than 96 hours since first positive COVID-19 test sample was taken 9. Unable to discontinue contra-indicated concomitant medications This is a multi-centre trial, patients will be recruited from in-patients and outpatients from three Glasgow hospitals: Royal Alexandra Hospital; Queen Elizabeth University Hospital; and the Glasgow Royal Infirmary. Intervention and comparator Patients randomised to the experimental arm of GETAFIX will receive standard treatment for COVID-19 at the discretion of the treating clinician plus favipiravir. These patients will receive a loading dose of favipiravir on day 1 of 3600mg (1800mg 12 hours apart). On days 2-10, patients in the experimental arm will receive a maintenance dose of favipiravir of 800mg 12 hours apart (total of 18 doses). Patients randomised to the control arm of the GETAFIX trial will receive standard treatment for COVID-19 at the discretion of the treating clinician. Main outcomes The primary outcome being assessed in the GETAFIX trial is the efficacy of favipiravir in addition to standard treatment in patients with COVID-19 in reducing the severity of disease compared to standard treatment alone. Disease severity will be assessed using WHO COVID 10 point ordinal severity scale at day 15 +/- 48 hours. All randomised participants will be followed up until death or 60 days post-randomisation (whichever is sooner). Randomisation Patients will be randomised 1:1 to the experimental versus control arm using computer generated random sequence allocation. A minimisation algorithm incorporating a random component will be used to allocate patients. The factors used in the minimisation will be: site, age (16-50/51-70/71+), history of hypertension or currently obsess (BMI>30 or obesity clinically evident; yes/no), 7 days duration of symptoms (yes/no/unknown), sex (male/female), WHO COVID-19 ordinal severity score at baseline (1/2or 3/4). Blinding (masking) No blinding will be used in the GETAFIX trial. Both participants and those assessing outcomes will be aware of treatment allocation. Numbers to be randomised (sample size) In total, 302 patients will be randomised to the GETAFIX trial: 151 to the control arm and 151 to the experimental arm. There will be an optional consent form for patients who may want to contribute to more frequent PK and PD sampling. The maximum number of patients who will undergo this testing will be sixteen, eight males and eight females. This option will be offered to all patients who are being treated in hospital at the time of taking informed consent, however only patients in the experimental arm of the trial will be able to undergo this testing. Trial Status The current GETAFIX protocol is version 4.0 12th September 2020. GETAFIX opened to recruitment on 26th October 2020 and will recruit patients over a period of approximately six months. Trial registration GETAFIX was registered on the European Union Drug Regulating Authorities Clinical Trials (EudraCT) Database on 15th April 2020; Reference number 2020-001904-41 (https://www.clinicaltrialsregister.eu/ctr-search/trial/2020-001904-41/GB). GETAFIX was registered on ISRCTN on 7th September 2020; Reference number ISRCTN31062548 (https://www.isrctn.com/ISRCTN31062548). Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (see Additional file 2).

The structural basis of minor groove recognition of a DNA duplex containing synthetic genetic information by hairpin pyrrole-imidazole polyamides is described. Hairpin polyamides induce a higher melting stabilization of a DNA duplex containing the unnatural P·Z base-pair when an imidazole unit is aligned with a P nucleotide. An NMR structural study showed that the incorporation of two isolated P·Z pairs enlarges the minor groove and slightly narrows the major groove at the site of this synthetic genetic information, relative to a DNA duplex consisting entirely of Watson-Crick base-pairs. Pyrrole-imidazole polyamides bind to a P·Z-containing DNA duplex to form a stable complex, effectively mimicking a G·C pair. A structural hallmark of minor groove recognition of a P·Z pair by a polyamide is the reduced level of allosteric distortion induced by binding of a polyamide to a DNA duplex. Understanding the molecular determinants that influence minor groove recognition of DNA containing synthetic genetic components provides the basis to further develop unnatural base-pairs for synthetic biology applications.