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Synthesis of colicin A after induction with mitomycin C was studied. Specific inhibition of chromosomal protein synthesis occurred very shortly after mitomycin addition. There was no coordinate synthesis of colicin A (61 000 Mr) and low-molecular-weight protein. Free and membrane-bound polysome fractions were isolated from cells induced with mitomycin C. Colicin A is synthesized in vitro in the free polysomes and not in the membranebound polysomes. Conditions are described which allow a practically specific labelling of colicin A in vivo. By using this system it was possible to demonstrate that colicin A is not transferred cotranslationally across the cytoplasmic membrane. In contrast, this protein leaves the cell where it is made long after synthesis. Preliminary evidence, suggesting that pauses occur during synthesis of colicin A, is presented. [ABSTRACT FROM AUTHOR]

Background: As acceptance of artificial intelligence [AI] platforms increases, more patients will consider these tools as sources of information. The ChatGPT architecture utilizes a neural network to process natural language, thus generating responses based on the context of input text. The accuracy and completeness of ChatGPT3.5 in the context of inflammatory bowel disease [IBD] remains unclear., Methods: In this prospective study, 38 questions worded by IBD patients were inputted into ChatGPT3.5. The following topics were covered: [1] Crohn's disease [CD], ulcerative colitis [UC], and malignancy; [2] maternal medicine; [3] infection and vaccination; and [4] complementary medicine. Responses given by ChatGPT were assessed for accuracy [1-completely incorrect to 5-completely correct] and completeness [3-point Likert scale; range 1-incomplete to 3-complete] by 14 expert gastroenterologists, in comparison with relevant ECCO guidelines., Results: In terms of accuracy, most replies [84.2%] had a median score of ≥4 (interquartile range [IQR]: 2) and a mean score of 3.87 [SD: ±0.6]. For completeness, 34.2% of the replies had a median score of 3 and 55.3% had a median score of between 2 and <3. Overall, the mean rating was 2.24 [SD: ±0.4, median: 2, IQR: 1]. Though groups 3 and 4 had a higher mean for both accuracy and completeness, there was no significant scoring variation between the four question groups [Kruskal-Wallis test p > 0.05]. However, statistical analysis for the different individual questions revealed a significant difference for both accuracy [p < 0.001] and completeness [p < 0.001]. The questions which rated the highest for both accuracy and completeness were related to smoking, while the lowest rating was related to screening for malignancy and vaccinations especially in the context of immunosuppression and family planning., Conclusion: This is the first study to demonstrate the capability of an AI-based system to provide accurate and comprehensive answers to real-world patient queries in IBD. AI systems may serve as a useful adjunct for patients, in addition to standard of care in clinics and validated patient information resources. However, responses in specialist areas may deviate from evidence-based guidance and the replies need to give more firm advice., (© The Author(s) 2024. Published by Oxford University Press on behalf of European Crohn’s and Colitis Organisation. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

After the successful roll out of MenAfriVac, Nigeria has experienced sequential meningitis outbreaks attributed to meningococcus serogroup C (NmC). Zamfara State in North-western Nigeria recently was at the epicentre of the largest NmC outbreak in the 21 st Century with 7,140 suspected meningitis cases and 553 deaths reported between December 2016 and May 2017. The overall attack rate was 155 per 100,000 population and children 5-14 years accounted for 47% (3,369/7,140) of suspected cases. The case fatality rate (CFR) among children 5-9 years was 10%, double that reported among adults ≥ 30 years (5%). NmC and pneumococcus accounted for 94% (172/184) and 5% (9/184) of the laboratory-confirmed cases, respectively. The sequenced NmC belonged to the ST-10217 clonal complex (CC). All serotyped pneumococci were PCV10 serotypes. The emergence of NmC ST-10217 CC outbreaks threatens the public health gains made by MenAfriVac, which calls for an urgent strategic action against meningitis outbreaks.

As part of the UK response to the 2013-2016 Ebola virus disease (EVD) epidemic in West Africa, Public Health England (PHE) were tasked with establishing three field Ebola virus (EBOV) diagnostic laboratories in Sierra Leone by the UK Department for International Development (DFID). These provided diagnostic support to the Ebola Treatment Centre (ETC) facilities located in Kerry Town, Makeni and Port Loko. The Novel and Dangerous Pathogens (NADP) Training group at PHE, Porton Down, designed and implemented a pre-deployment Ebola diagnostic laboratory training programme for UK volunteer scientists being deployed to the PHE EVD laboratories. Here, we describe the training, workflow and capabilities of these field laboratories for use in response to disease epidemics and in epidemiological surveillance. We discuss the training outcomes, the laboratory outputs, lessons learned and the legacy value of the support provided. We hope this information will assist in the recruitment and training of staff for future responses and in the design and implementation of rapid deployment diagnostic field laboratories for future outbreaks of high consequence pathogens.This article is part of the themed issue 'The 2013-2016 West African Ebola epidemic: data, decision-making and disease control'., (© 2017 The Author(s).)

We have developed an enhanced form of reduced representation bisulfite sequencing with extended genomic coverage, which resulted in greater capture of DNA methylation information of regions lying outside of traditional CpG islands. Applying this method to primary human bone marrow specimens from patients with Acute Myelogeneous Leukemia (AML), we demonstrated that genetically distinct AML subtypes display diametrically opposed DNA methylation patterns. As compared to normal controls, we observed widespread hypermethylation in IDH mutant AMLs, preferentially targeting promoter regions and CpG islands neighboring the transcription start sites of genes. In contrast, AMLs harboring translocations affecting the MLL gene displayed extensive loss of methylation of an almost mutually exclusive set of CpGs, which instead affected introns and distal intergenic CpG islands and shores. When analyzed in conjunction with gene expression profiles, it became apparent that these specific patterns of DNA methylation result in differing roles in gene expression regulation. However, despite this subtype-specific DNA methylation patterning, a much smaller set of CpG sites are consistently affected in both AML subtypes. Most CpG sites in this common core of aberrantly methylated CpGs were hypermethylated in both AML subtypes. Therefore, aberrant DNA methylation patterns in AML do not occur in a stereotypical manner but rather are highly specific and associated with specific driving genetic lesions., Competing Interests: GPS, IK, LZ, and JB are currently or have until recently been employed by Illumina.

Increased productivity in DNA sequencing would not be valid without a straightforward detection and estimation of errors in finished sequences. The sequence of the surfactin operon from Bacillus subtilis was obtained by two different groups and by chance we were also working on the same chromosome region. Taking advantage of this situation we report in this paper, the number and nature of errors found in the overlapping part of the DNA sequences obtained by the three laboratories. The coincidence of some of the errors with compression in sequence ladders and with secondary DNA structures as well as the detection of frameshift errors using computer programs, are demonstrated. Finally we discuss the definition of a new sequencing strategy that might minimize both the error rate and the cost of sequencing.

A periplasmic aminoendopeptidase from Escherichia coli has been purified to hemogeneity. It is a monomer of molecular weight 45000 and containing one -- SH group that is necessary for catalytic activity. The study of its substrate specificity indicated that the enzyme has both aminopeptidase and endopeptidase activity. The pH optimum for L-alanine p-nitroanilide hydrolysis is between 7 and 7.5 and that for 125I-labeled casein proteolysis between 7.3 and 7.6. The activation energy for the hydrolysis of L-anine p-nitroanilide was calculated to be 5.3 kcal X mol-1 (22.2 kJ X mol-1).