Food safety is a significant barrier to social and economic development throughout the world, particularly in developing countries. Here, we reviewed the prevalence of major bacterial foodborne ...pathogens (Salmonella spp., Listeria monocytogenes, Escherichia coli O157:H7 and Campylobacter spp.) in the rapidly growing Ethiopian dairy supply-chain. We identified 15, 9, 5 and 0 studies that had reported the prevalence of Salmonella spp., L. monocytogenes, E. coli O157:H7, and Campylobacter spp. in dairy foods, respectively. The studies reviewed reported a median prevalence of Salmonella, L. monocytogenes, and E. coli O157:H7 of 6, 9 and 10%, respectively, in raw cow milk in Ethiopia, indicating a concerning occurrence of bacterial foodborne pathogens in raw milk. Implementation of good hygiene and production practices and assessment of interventions targeting the reduction of contamination in the dairy supply chain is needed to inform coordinated efforts focused on improvement of dairy food safety in Ethiopia.
The emergence of antimicrobial-resistant (AMR) strains of the important human and animal pathogen Salmonella enterica poses a growing threat to public health. Here, we studied the genome-wide ...evolution of 90 S. enterica AMR isolates, representing one host adapted serotype (S. Dublin) and two broad host range serotypes (S. Newport and S. Typhimurium).
AMR S. Typhimurium had a large effective population size, a large and diverse genome, AMR profiles with high diversity, and frequent positive selection and homologous recombination. AMR S. Newport showed a relatively low level of diversity and a relatively clonal population structure. AMR S. Dublin showed evidence for a recent population bottleneck, and the genomes were characterized by a larger number of genes and gene ontology terms specifically absent from this serotype and a significantly higher number of pseudogenes as compared to other two serotypes. Approximately 50% of accessory genes, including specific AMR and putative prophage genes, were significantly over- or under-represented in a given serotype. Approximately 65% of the core genes showed phylogenetic clustering by serotype, including the AMR gene aac (6')-Iaa. While cell surface proteins were shown to be the main target of positive selection, some proteins with possible functions in AMR and virulence also showed evidence for positive selection. Homologous recombination mainly acted on prophage-associated proteins.
Our data indicates a strong association between genome content of S. enterica and serotype. Evolutionary patterns observed in S. Typhimurium are consistent with multiple emergence events of AMR strains and/or ecological success of this serotype in different hosts or habitats. Evolutionary patterns of S. Newport suggested that antimicrobial resistance emerged in one single lineage, Lineage IIC. A recent population bottleneck and genome decay observed in AMR S. Dublin are congruent with its narrow host range. Finally, our results suggest the potentially important role of positive selection in the evolution of antimicrobial resistance, host adaptation and serotype diversification in S. enterica.
Genomics and related tools are beginning to have a tremendous impact on food safety by allowing for a more precise approach to pathogen detection, characterization, and identification. The data ...produced using these tools are expected to lead to a paradigm shift in modern food safety concepts with impacts similar to those facilitated through development of personalized medicine methods in human medicine. We hence envision a future of food safety that can be best described as “precision food safety”. While precision food safety will employ a number of new approaches and methods, omics tools will play a particularly important role and will provide for improved and more precise food safety procedures, including increasingly accurate risk assessment that will support evidence-based food safety decision-making. This review will highlight examples where genomics-based precision food safety approaches will have a significant impact.
•Omics tools allow for accurate characterization and identification of pathogens.•Precision food safety is a systems approach to omics-supported food safety.•Precision food safety framework facilitates more accurate risk assessment.
A strain of lactic acid bacteria, designated 159469
, isolated from a facial abscess in a sugar glider, was characterized genetically and phenotypically. Cells of the strain were Gram-stain-positive, ...coccoid and catalase-negative. Morphological, physiological and phylogenetic data indicated that the isolate belongs to the genus Lactococcus. Strain 159469
was closely related to Lactococcus garvieae ATCC 43921
, showing 95.86 and 98.08 % sequence similarity in 16S rRNA gene and rpoB gene sequences, respectively. Furthermore, a pairwise average nucleotide identity blast (ANIb) value of 93.54 % and in silico DNA-DNA hybridization value of 50.7 % were determined for the genome of strain 159469
, when compared with the genome of the type strain of Lactococcus garvieae. Based on the data presented here, the isolate represents a novel species of the genus Lactococcus, for which the name Lactococcus petauri sp. nov. is proposed. The type strain is 159469
(=LMG 30040
=DSM 104842
).
Additive manufacturing methods
using static and mobile robots are being developed for both on-site construction
and off-site prefabrication
. Here we introduce a method of additive manufacturing, ...referred to as aerial additive manufacturing (Aerial-AM), that utilizes a team of aerial robots inspired by natural builders
such as wasps who use collective building methods
. We present a scalable multi-robot three-dimensional (3D) printing and path-planning framework that enables robot tasks and population size to be adapted to variations in print geometry throughout a building mission. The multi-robot manufacturing framework allows for autonomous three-dimensional printing under human supervision, real-time assessment of printed geometry and robot behavioural adaptation. To validate autonomous Aerial-AM based on the framework, we develop BuilDrones for depositing materials during flight and ScanDrones for measuring the print quality, and integrate a generic real-time model-predictive-control scheme with the Aerial-AM robots. In addition, we integrate a dynamically self-aligning delta manipulator with the BuilDrone to further improve the manufacturing accuracy to five millimetres for printing geometry with precise trajectory requirements, and develop four cementitious-polymeric composite mixtures suitable for continuous material deposition. We demonstrate proof-of-concept prints including a cylinder 2.05 metres high consisting of 72 layers of a rapid-curing insulation foam material and a cylinder 0.18 metres high consisting of 28 layers of structural pseudoplastic cementitious material, a light-trail virtual print of a dome-like geometry, and multi-robot simulations. Aerial-AM allows manufacturing in-flight and offers future possibilities for building in unbounded, at-height or hard-to-access locations.
Dissociative seizures are paroxysmal events resembling epilepsy or syncope with characteristic features that allow them to be distinguished from other medical conditions. We aimed to compare the ...effectiveness of cognitive behavioural therapy (CBT) plus standardised medical care with standardised medical care alone for the reduction of dissociative seizure frequency.
In this pragmatic, parallel-arm, multicentre randomised controlled trial, we initially recruited participants at 27 neurology or epilepsy services in England, Scotland, and Wales. Adults (≥18 years) who had dissociative seizures in the previous 8 weeks and no epileptic seizures in the previous 12 months were subsequently randomly assigned (1:1) from 17 liaison or neuropsychiatry services following psychiatric assessment, to receive standardised medical care or CBT plus standardised medical care, using a web-based system. Randomisation was stratified by neuropsychiatry or liaison psychiatry recruitment site. The trial manager, chief investigator, all treating clinicians, and patients were aware of treatment allocation, but outcome data collectors and trial statisticians were unaware of treatment allocation. Patients were followed up 6 months and 12 months after randomisation. The primary outcome was monthly dissociative seizure frequency (ie, frequency in the previous 4 weeks) assessed at 12 months. Secondary outcomes assessed at 12 months were: seizure severity (intensity) and bothersomeness; longest period of seizure freedom in the previous 6 months; complete seizure freedom in the previous 3 months; a greater than 50% reduction in seizure frequency relative to baseline; changes in dissociative seizures (rated by others); health-related quality of life; psychosocial functioning; psychiatric symptoms, psychological distress, and somatic symptom burden; and clinical impression of improvement and satisfaction. p values and statistical significance for outcomes were reported without correction for multiple comparisons as per our protocol. Primary and secondary outcomes were assessed in the intention-to-treat population with multiple imputation for missing observations. This trial is registered with the International Standard Randomised Controlled Trial registry, ISRCTN05681227, and ClinicalTrials.gov, NCT02325544.
Between Jan 16, 2015, and May 31, 2017, we randomly assigned 368 patients to receive CBT plus standardised medical care (n=186) or standardised medical care alone (n=182); of whom 313 had primary outcome data at 12 months (156 84% of 186 patients in the CBT plus standardised medical care group and 157 86% of 182 patients in the standardised medical care group). At 12 months, no significant difference in monthly dissociative seizure frequency was identified between the groups (median 4 seizures IQR 0–20 in the CBT plus standardised medical care group vs 7 seizures 1–35 in the standardised medical care group; estimated incidence rate ratio IRR 0·78 95% CI 0·56–1·09; p=0·144). Dissociative seizures were rated as less bothersome in the CBT plus standardised medical care group than the standardised medical care group (estimated mean difference −0·53 95% CI −0·97 to −0·08; p=0·020). The CBT plus standardised medical care group had a longer period of dissociative seizure freedom in the previous 6 months (estimated IRR 1·64 95% CI 1·22 to 2·20; p=0·001), reported better health-related quality of life on the EuroQoL-5 Dimensions-5 Level Health Today visual analogue scale (estimated mean difference 6·16 95% CI 1·48 to 10·84; p=0·010), less impairment in psychosocial functioning on the Work and Social Adjustment Scale (estimated mean difference −4·12 95% CI −6·35 to −1·89; p<0·001), less overall psychological distress than the standardised medical care group on the Clinical Outcomes in Routine Evaluation-10 scale (estimated mean difference −1·65 95% CI −2·96 to −0·35; p=0·013), and fewer somatic symptoms on the modified Patient Health Questionnaire-15 scale (estimated mean difference −1·67 95% CI −2·90 to −0·44; p=0·008). Clinical improvement at 12 months was greater in the CBT plus standardised medical care group than the standardised medical care alone group as reported by patients (estimated mean difference 0·66 95% CI 0·26 to 1·04; p=0·001) and by clinicians (estimated mean difference 0·47 95% CI 0·21 to 0·73; p<0·001), and the CBT plus standardised medical care group had greater satisfaction with treatment than did the standardised medical care group (estimated mean difference 0·90 95% CI 0·48 to 1·31; p<0·001). No significant differences in patient-reported seizure severity (estimated mean difference −0·11 95% CI −0·50 to 0·29; p=0·593) or seizure freedom in the last 3 months of the study (estimated odds ratio OR 1·77 95% CI 0·93 to 3·37; p=0·083) were identified between the groups. Furthermore, no significant differences were identified in the proportion of patients who had a more than 50% reduction in dissociative seizure frequency compared with baseline (OR 1·27 95% CI 0·80 to 2·02; p=0·313). Additionally, the 12-item Short Form survey–version 2 scores (estimated mean difference for the Physical Component Summary score 1·78 95% CI −0·37 to 3·92; p=0·105; estimated mean difference for the Mental Component Summary score 2·22 95% CI −0·30 to 4·75; p=0·084), the Generalised Anxiety Disorder-7 scale score (estimated mean difference −1·09 95% CI −2·27 to 0·09; p=0·069), and the Patient Health Questionnaire-9 scale depression score (estimated mean difference −1·10 95% CI −2·41 to 0·21; p=0·099) did not differ significantly between groups. Changes in dissociative seizures (rated by others) could not be assessed due to insufficient data. During the 12-month period, the number of adverse events was similar between the groups: 57 (31%) of 186 participants in the CBT plus standardised medical care group reported 97 adverse events and 53 (29%) of 182 participants in the standardised medical care group reported 79 adverse events.
CBT plus standardised medical care had no statistically significant advantage compared with standardised medical care alone for the reduction of monthly seizures. However, improvements were observed in a number of clinically relevant secondary outcomes following CBT plus standardised medical care when compared with standardised medical care alone. Thus, adults with dissociative seizures might benefit from the addition of dissociative seizure-specific CBT to specialist care from neurologists and psychiatrists. Future work is needed to identify patients who would benefit most from a dissociative seizure-specific CBT approach.
National Institute for Health Research, Health Technology Assessment programme.
Effective control of foodborne pathogens on produce requires science-based validation of interventions and control strategies, which typically involves challenge studies with a set of bacterial ...strains representing the target pathogens or appropriate surrogates. In order to facilitate these types of studies, a produce-relevant strain collection was assembled to represent strains from produce outbreaks or pre-harvest environments, including
(
= 11),
(
= 23), shiga-toxin producing
(STEC) (
= 13), and possible surrogate organisms (
= 8); all strains were characterized by whole genome sequencing (WGS). Strain diversity was assured by including the 10 most common
serotypes,
lineages I-IV, and
O157 as well as selected "non-O157" STEC serotypes. As it has previously been shown that strains and genetic lineages of a pathogen may differ in their ability to survive different stress conditions, a subset of representative strains for each "pathogen group" (e.g.,
, STEC) was selected and assessed for survival of exposure to peroxyacetic acid (PAA) using strains pre-grown under different conditions including (i) low pH, (ii) high salt, (iii) reduced water activity, (iv) different growth phases, (v) minimal medium, and (vi) different temperatures (21°C, 37°C). The results showed that across the three pathogen groups pre-growth conditions had a larger effect on bacterial reduction after PAA exposure as compared to strain diversity. Interestingly, bacteria exposed to salt stress (4.5% NaCl) consistently showed the least reduction after exposure to PAA; however, for STEC, strains pre-grown at 21°C were as tolerant to PAA exposure as strains pre-grown under salt stress. Overall, our data suggests that challenge studies conducted with multi-strain cocktails (pre-grown under a single specific condition) may not necessarily reflect the relevant phenotypic range needed to appropriately assess different intervention strategies.
This article presents results of hydrogeological and hydrogeochemical research conducted at south hills, Ivanščica Mountain, situated in the northwestern part of the Republic of Croatia. Research was ...carried out in the summer 2013, between July and September. Hydrogeological mapping was undertaken on approximately 20 km
2
(at a scale of 1:25000), with water samples taken from 10 springs. Rocks and deposits were classified into three hydrogeological units with respect to permeability. Two main aquifers were identified - the Triassic carbonate aquifer and the Badenian carbonate aquifer. The overall capacity of 41 registered springs (permanent and periodic) was estimated. According to their basic chemical composition, water from springs belong to Ca-HCO
3
(calcium-hydrogen carbonate), CaMg-HCO
3
(calcium magnesium-hydrogen carbonate) and to MgCa-HCO
3
(magnesium calcium-hydrogen carbonate) types.
This study addresses the limited tools available for assessing food safety risks from cytotoxic Bacillus cereus group strains in contaminated food. We quantified the growth, in skim milk broth, of 17 ...cytotoxic B. cereus strains across 6 phylogenetic groups with various virulence gene profiles. The strains did not grow in HTST milk at 4 or 6°C. At 10°C, 15 strains exhibited growth; at 8°C, one strain grew; and all strains grew at temperatures ≥ 14°C. Using growth data from 16 strains, we developed linear secondary growth models and an exposure assessment model. This model, simulating a 5-stage HTST milk supply chain and up to 35 d of consumer storage with an initial contamination of 100 cfu/mL, estimated that 2.81 ± 0.66% and 4.13 ± 2.53% of milk containers would surpass 105 cfu/mL of B. cereus by d 21 and 35, respectively. A sensitivity analysis identified the initial physiological state of cells (Q0) as the most influential variable affecting predictions for specific isolates. What-if scenarios indicated that increases in mean and variability of consumer storage temperatures significantly affected the predicted B. cereus concentrations in milk. This model serves as an initial tool for risk-based food safety decision making regarding low-level B. cereus contamination.
Considering sex as a biological variable in modern digital health solutions, we investigated sex-specific differences in the trajectory of four physiological parameters across a COVID-19 infection. A ...wearable medical device measured breathing rate, heart rate, heart rate variability, and wrist skin temperature in 1163 participants (mean age = 44.1 years, standard deviation SD = 5.6; 667 57% females). Participants reported daily symptoms and confounders in a complementary app. A machine learning algorithm retrospectively ingested daily biophysical parameters to detect COVID-19 infections. COVID-19 serology samples were collected from all participants at baseline and follow-up. We analysed potential sex-specific differences in physiology and antibody titres using multilevel modelling and t-tests. Over 1.5 million hours of physiological data were recorded. During the symptomatic period of infection, men demonstrated larger increases in skin temperature, breathing rate, and heart rate as well as larger decreases in heart rate variability than women. The COVID-19 infection detection algorithm performed similarly well for men and women. Our study belongs to the first research to provide evidence for differential physiological responses to COVID-19 between females and males, highlighting the potential of wearable technology to inform future precision medicine approaches.
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