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SUMMARYA challenge for screening new candidate drugs to treat cancer is that efficacy in cell culture models is not always predictive of efficacy in patients. One limitation of standard cell culture is a reliance on non-physiological nutrient levels to propagate cells. Which nutrients are available can influence how cancer cells use metabolism to proliferate and impact sensitivity to some drugs, but a general assessment of how physiological nutrients affect cancer cell response to small molecule therapies is lacking. To enable screening of compounds to determine how the nutrient environment impacts drug efficacy, we developed a serum-derived culture medium that supports the proliferation of diverse cancer cell lines and is amenable to high-throughput screening. We used this system to screen several small molecule libraries and found that compounds targeting metabolic enzymes were enriched as having differential efficacy in standard compared to serum-derived medium. We exploited the differences in nutrient levels between each medium to understand why medium conditions affected the response of cells to some compounds, illustrating how this approach can be used to screen potential therapeutics and understand how their efficacy is modified by available nutrients.

BACKGROUND Cardiac dysfunction is frequently observed in patients with cirrhosis. There remains a paucity of data from routine clinical practice regarding the role of echocardiography in the pre-assessment of transjugular intrahepatic portosystemic stent-shunt. AIM Our study aimed to investigate if echocardiography parameters predict outcomes after transjugular intrahepatic portosystemic stent-shunt insertion in cirrhosis. METHODS Patients who underwent echocardiography and transjugular intrahepatic portosystemic stent-shunt insertion at the liver unit (Birmingham, UK) between 1999 and 2016 were included. All echocardiography measures (including left ventricle ejection fraction; early maximal ventricular filling/late filling velocity ratio, diastolic dysfunction as per British Society of Echocardiography guidelines) were independently reviewed by a cardiologist. Predictors of 30-day and overall transplant free-survival were assessed. RESULTS One Hundred and Seventeen patients with cirrhosis (median age 56 years; 54% alcohol; Child-Pugh B/C 71/14.5%; Model For End-Stage Liver Disease 12) underwent transjugular intrahepatic portosystemic stent-shunt for ascites (n = 78) and variceal haemorrhage (n = 39). Thirty-day and overall transplant-free survival was 90% (n = 105) and 31% (n = 36), respectively, over a median 663 (IQR 385-2368) days follow-up. Model for End-Stage Liver Disease (P

BACKGROUND: Staphylococcus aureus bacteraemia is a common cause of severe community-acquired and hospital-acquired infection worldwide. We tested the hypothesis that adjunctive rifampicin would reduce bacteriologically confirmed treatment failure or disease recurrence, or death, by enhancing early S aureus killing, sterilising infected foci and blood faster, and reducing risks of dissemination and metastatic infection.METHODS: In this multicentre, randomised, double-blind, placebo-controlled trial, adults (≥18 years) with S aureus bacteraemia who had received ≤96 h of active antibiotic therapy were recruited from 29 UK hospitals. Patients were randomly assigned (1:1) via a computer-generated sequential randomisation list to receive 2 weeks of adjunctive rifampicin (600 mg or 900 mg per day according to weight, oral or intravenous) versus identical placebo, together with standard antibiotic therapy. Randomisation was stratified by centre. Patients, investigators, and those caring for the patients were masked to group allocation. The primary outcome was time to bacteriologically confirmed treatment failure or disease recurrence, or death (all-cause), from randomisation to 12 weeks, adjudicated by an independent review committee masked to the treatment. Analysis was intention to treat. This trial was registered, number ISRCTN37666216, and is closed to new participants.FINDINGS: Between Dec 10, 2012, and Oct 25, 2016, 758 eligible participants were randomly assigned: 370 to rifampicin and 388 to placebo. 485 (64%) participants had community-acquired S aureus infections, and 132 (17%) had nosocomial S aureus infections. 47 (6%) had meticillin-resistant infections. 301 (40%) participants had an initial deep infection focus. Standard antibiotics were given for 29 (IQR 18-45) days; 619 (82%) participants received flucloxacillin. By week 12, 62 (17%) of participants who received rifampicin versus 71 (18%) who received placebo experienced treatment failure or disease recurrence, or died (absolute risk difference -1·4%, 95% CI -7·0 to 4·3; hazard ratio 0·96, 0·68-1·35, p=0·81). From randomisation to 12 weeks, no evidence of differences in serious (p=0·17) or grade 3-4 (p=0·36) adverse events were observed; however, 63 (17%) participants in the rifampicin group versus 39 (10%) in the placebo group had antibiotic or trial drug-modifying adverse events (p=0·004), and 24 (6%) versus six (2%) had drug interactions (p=0·0005).INTERPRETATION: Adjunctive rifampicin provided no overall benefit over standard antibiotic therapy in adults with S aureus bacteraemia.FUNDING: UK National Institute for Health Research Health Technology Assessment.

Background The term ‘zero tolerance’ has recently been applied to healthcare-associated infections, implying that such events are always preventable. This may not be the case for healthcare-associated infections such as methicillin-resistant Staphylococcus aureus (MRSA) bacteraemia. Methods We combined information from an epidemiological investigation and bacterial whole-genome sequencing to evaluate a cluster of five MRSA bacteraemia episodes in four patients in a specialist hepatology unit. Results The five MRSA bacteraemia isolates were highly related by multilocus sequence type (ST) (four isolates were ST22 and one isolate was a single-locus variant, ST2046). Whole-genome sequencing demonstrated unequivocally that the bacteraemia cases were unrelated. Placing the MRSA bacteraemia isolates within a local and global phylogenetic tree of MRSA ST22 genomes demonstrated that the five bacteraemia isolates were highly diverse. This was consistent with the acquisition and importation of MRSA from the wider referral network. Analysis of MRSA carriage and disease in patients within the hepatology service demonstrated a higher risk of both initial MRSA acquisition compared with the nephrology service and a higher risk of progression from MRSA carriage to bacteraemia, compared with patients in nephrology or geriatric services. A root cause analysis failed to reveal any mechanism by which three of five MRSA bacteraemia episodes could have been prevented. Conclusions This study illustrates the complex nature of MRSA carriage and bacteraemia in patients in a specialized hepatology unit. Despite numerous ongoing interventions to prevent MRSA bacteraemia in healthcare settings, these are unlikely to result in a zero incidence in referral centres that treat highly complex patients.

Summary Background Increasing numbers of individuals with cystic fibrosis are becoming infected with the multidrug-resistant non-tuberculous mycobacterium (NTM) Mycobacterium abscessus , which causes progressive lung damage and is extremely challenging to treat. How this organism is acquired is not currently known, but there is growing concern that person-to-person transmission could occur. We aimed to define the mechanisms of acquisition of M abscessus in individuals with cystic fibrosis. Method Whole genome sequencing and antimicrobial susceptibility testing were done on 168 consecutive isolates of M abscessus from 31 patients attending an adult cystic fibrosis centre in the UK between 2007 and 2011. In parallel, we undertook detailed environmental testing for NTM and defined potential opportunities for transmission between patients both in and out of hospital using epidemiological data and social network analysis. Findings Phylogenetic analysis revealed two clustered outbreaks of near-identical isolates of the M abscessus subspecies massiliense (from 11 patients), differing by less than ten base pairs. This variation represents less diversity than that seen within isolates from a single individual, strongly indicating between-patient transmission. All patients within these clusters had numerous opportunities for within-hospital transmission from other individuals, while comprehensive environmental sampling, initiated during the outbreak, failed to detect any potential point source of NTM infection. The clusters of M abscessus subspecies massiliense showed evidence of transmission of mutations acquired during infection of an individual to other patients. Thus, isolates with constitutive resistance to amikacin and clarithromycin were isolated from several individuals never previously exposed to long-term macrolides or aminoglycosides, further indicating cross-infection. Interpretation Whole genome sequencing has revealed frequent transmission of multidrug resistant NTM between patients with cystic fibrosis despite conventional cross-infection measures. Although the exact transmission route is yet to be established, our epidemiological analysis suggests that it could be indirect. Funding The Wellcome Trust, Papworth Hospital, NIHR Cambridge Biomedical Research Centre, UK Health Protection Agency, Medical Research Council, and the UKCRC Translational Infection Research Initiative.

A 37 year old jockey was admitted with left sided abdominal pain and fullness one week after a fall from a horse. Before this he had been fit and well. On examination, he was tender in the left upper outer quadrant of his abdomen and his blood pressure was 90/55 mm Hg. A computed tomography scan showed an area of active bleeding in the parenchyma of the spleen and a large subcapsular haematoma. Blood tests showed a white blood cell count of 259×109/L (reference range 4-11) with the following differential: blasts 3%, promyelocytes 11%, myelocytes 28%, metamyelocytes 19%, neutrophils 21%, basophils 10%, lymphocytes 4%, and eosinophils 4%. His haemoglobin was 109 g/L (130-180), mean cell volume was 80 fL (76-96), and platelets were 201×109/L (150-400). Lactate dehydrogenase was 563 IU/L (70-250; 1 mmol/L=9.01 mg/dL) and uric acid was 600 µmol/L (300-470; 1 µmol/L=0.03 mg/dL). He underwent emergency splenectomy. Macroscopically, the spleen was greatly enlarged, at 22×13×10 cm, and microscopically it showed a dense infiltrate of left shifted immature myeloid cells. ### 1 What are the possible causes of a raised white blood cell count? #### Short answer A white blood cell count greater than 50×109/L is caused by a primary haematological disease or, less commonly at such a high value, a leukemoid reaction. A leukemoid reaction may be lymphoid or myeloid in nature and is a physiological response of the bone marrow to a strong stimulus, such as infection, drugs, or an underlying solid cancer. #### Long answer Causes of leucocytosis (>11×109/L) can be classified according to cell lineage (box 1). #### Box 1 Causes of leucocytosis (>11×109/L) ##### Neutrophilia