Membrane-aerated biofilm reactors (MABRs) are being increasingly being implemented at full-scale for domestic wastewater treatment and effective biofilm control is critical to their performance. This study investigated the impact of three biofilm scouring strategies on nitrogen removal performance of a pilot-scale MABR operated in Houston, TX: (1) regular air scouring, (2) high intensity air scouring, and (3) high liquid flow scouring. Normal and high intensity air scouring regimes and a high liquid flow scour (10x baseline flow) were each tested sequentially. High NH4+-N removal efficiency of 52% in flow-through mode was observed post-high liquid flow scouring, which was comparable to the performance during the intense scouring regime. The absolute abundance of amoA gene for ammonia oxidizing bacteria (AOB) increased significantly by over 200%, between pre- and post-high liquid flow scouring. The energy consumption was 43% lower for the combination of high liquid flow scouring with regular air scouring as compared to the intense air scouring. This study showed that high liquid flows may be utilized as an energy-efficient biofilm control strategy in nitrifying MABR systems. Practitioner Points Pilot-scale MABR reactors were operated with different scouring settings: regular aeration, intense aeration, and high liquid flow. High liquid flow scouring improved nitrification efficiency, comparable to intense scouring. High liquid flow scouring selected for nitrifiers as seen by an increase in AOB quantified as amoA gene abundance. Using high liquid flow with regular aeration scouring reduces electrical energy consumption by 43% as compared to intense aeration scouring. High liquid flows may be used as an energy-efficient biofilm control strategy to improve nitrification performance in MABR systems.
We describe detection of SAT2 topotype XIV foot-and-mouth disease viruses in western Asia during 2022-2023. Sequences show the viruses originated in eastern Africa and were introduced into western Asia on >1 occasion. The rapid spread in naive animals highlights risks for onward transmission and potential endemicity in Asia.
Foot-and-mouth disease virus (FMDV) is a highly contagious, economically important disease of livestock and wildlife species. Active monitoring and understanding the epidemiology of FMDV underpin the foundations of control programmes. In many endemic areas, however, veterinary resources are limited, resulting in a requirement for simple sampling techniques to increase and supplement surveillance efforts. In this study, environmental sampling was used for the first time at livestock markets and abattoirs across Cameroon to assess the opportunities for broad scale, non-invasive disease surveillance at such sites. Environmental samples (n = 1994) were collected from six locations across Cameroon between May and July 2019. Concurrent with environmental sampling, a questionnaire was used to gather descriptive information on the use and practices of market and abattoir sites. Samples were screened for the presence of FMDV RNA using a pan-serotype FMDV specific real-time RT-PCR assay. Positive samples were characterised at the genomic level using next generation sequencing in combination with a novel probe-based enrichment strategy. A total of 173/1994 (8.68%) environmental samples were found to be positive for FMDV RNA. Genome length sequences were obtained from environmental samples, with phylogenetically relevant capsid sequences obtained from 14 samples, with representatives of serotypes O (n = 6), A (n = 7) and SAT 2 (n = 3). The questionnaire results revealed that animals in Cameroon can be transported long distances to markets and abattoirs, with varying levels of control and biosecurity practices in place. The approaches used in this study have highlighted that environmental sampling is an effective and non-invasive approach to assessing FMDV presence. Furthermore, the study has demonstrated that livestock markets, abattoirs and trucks could be targeted for the introduction of biosecurity interventions as well as providing opportunities for carrying out disease surveillance. Information resulting from such surveillance could provide valuable knowledge of circulating viruses within a region of interest, aiding strategic approaches for surveillance and control of FMDV.
Foot-and-mouth disease (FMD) is a highly contagious disease affecting cloven-hoofed ungulates. This study aimed to enhance our understanding of the role of small ruminants and environmental contamination in the epidemiology and endemicity of FMD. A longitudinal study was conducted between March 2021 and October 2021 in northern Nigeria, where monthly samples were collected from five households, one livestock market and one transhumance location in two local government areas (LGA) identified as being at high risk of FMD. Serum samples (n = 783), oral swabs (n = 424) and environmental swabs (n = 458) were collected and tested for the presence of foot-and-mouth disease virus (FMDV) RNA by rRT-PCR. Serum samples (n = 780) were also tested for the presence of antibodies against FMDV non-structural proteins. The proportion of FMDV RNA positive samples increased in all sample types collected in one LGA during the period when an FMD outbreak was reported in the same LGA. In contrast, sero-positive samples did not differ by month but differed between LGAs and amongst species. The force of infection estimated from age-seroprevalence data for each household was significantly lower in goats compared with both cattle or sheep. Five O/EA-3 topotype sequences were obtained from selected FMDV RNA positive samples; findings which support the use of environmental swabs to detect circulating FMDV strains in endemic settings. These results show oral and environmental swabs are suitable sampling methods for early detection at animal and herd level, respectively and provide insights on the role of small ruminants on FMD epidemiology.
Multiple transboundary animal diseases (TADs) circulate in Plateau State, Nigeria, where livestock keeping is common and contributes to both the physical and socio-economic well-being of a large proportion of the population. In this study, we explored the potential for environmental sampling to detect viruses causing TADs circulating in the region. Electrostatic dust cloths were used to swab areas of the environment likely to have contact with secretions and excretions from infected animals. Samples were collected monthly from five households, one transhumance site and one livestock market in two local government areas in Plateau State between March and October 2021. These were tested for the presence of peste des petits ruminants virus (PPRV) and capripox viruses using real-time PCR. Of the 458 samples collected, 2.4% (n = 11) were positive for PPRV RNA and 1.3 % (n = 6) were positive for capripox virus DNA. A capripox differentiation assay showed that these samples were positive for sheep pox virus (n = 2), goat pox virus (n = 2) and lumpy skin disease virus (n = 2). Our results demonstrate that environmental sampling could be used as part of TAD surveillance in the area. Environmental swabs require little technical knowledge to collect and can be used to detect multiple viruses from a single sample.
Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-hoofed animals responsible for economic losses that amount to >$20 billion annually. Rapid recognition of FMD cases provides vital information to guide control programmes. A range of point-of-need amplification technologies have been developed which allow sensitive detection of the causative virus (FMDV) in the field at locations remote from laboratories. Here we describe a novel system to detect FMDV RNA using loop-mediated isothermal amplification (LAMP). This test was evaluated using a panel of FMDV isolates (n = 79) and RNA standards demonstrating capability to amplify viral genome directly from clinical material in the absence of nucleic acid extraction. This extraction-free RT-LAMP assay was transferred to a bespoke closed-system lateral flow test (LFT) that was used in combination with a low-cost hand-held heater. Our results show that the RT-LAMP-LFT assay retains a high level of diagnostic and analytical sensitivity when using direct clinical material, with a limit of detection under 80 copies per reaction. Together, our data support the potential for the use of this assay at the point-of-need to facilitate rapid feedback on the status of suspect cases.
In the original publication [...].
The water sector is in the middle of a paradigm shift from focusing on treatment and meeting discharge permit limits to integrated operation that also enables a circular water economy via water reuse, resource recovery, and system level planning and operation. While the sector has gone through different stages of such revolution, from improving energy efficiency to recovering renewable energy and resources, when it comes to the next step of achieving carbon neutrality or negative emission, it falls behind other infrastructure sectors such as energy and transportation. The water sector carries tremendous potential to decarbonize, from technological advancements, to operational optimization, to policy and behavioural changes.This book aims to fill an important gap for different stakeholders to gain knowledge and skills in this area and equip the water community to further decarbonize the industry and build a carbon-free society and economy. The book goes beyond technology overviews, rather it aims to provide a system level blueprint for decarbonization. It can be a reference book and textbook for graduate students, researchers, practitioners, consultants and policy makers, and it will provide practical guidance for stakeholders to analyse and implement decarbonization measures in their professions.English edition available https://iwaponline.com/ebooks/book/843/Pathways-to-Water-Sector-Decarbonization-Carbon
Abstract Foot‐and‐mouth disease (FMD) affects the livestock industry and socioeconomic sustainability of many African countries. The success of FMD control programs in Africa depends largely on understanding the dynamics of FMD virus (FMDV) spread. In light of the recent outbreaks of FMD that affected the North‐Western African countries in 2018 and 2019, we investigated the evolutionary phylodynamics of the causative serotype O viral strains all belonging to the East‐Africa 3 topotype (O/EA‐3). We analyzed a total of 489 sequences encoding the FMDV VP1 genome region generated from samples collected from 25 African and Western Asian countries between 1974 and 2019. Using Bayesian evolutionary models on genomic and epidemiological data, we inferred the routes of introduction and migration of the FMDV O/EA‐3 topotype at the inter‐regional scale. We inferred a mean substitution rate of 6.64 × 10−3 nt/site/year and we predicted that the most recent common ancestor for our panel of samples circulated between February 1967 and November 1973 in Yemen, likely reflecting the epidemiological situation in under sampled cattle‐exporting East African countries. Our study also reinforces the role previously described of Sudan and South Sudan as a frequent source of FMDVs spread. In particular, we identified two transboundary routes of O/EA‐3 diffusion: the first from Sudan to North‐East Africa, and from the latter into Israel and Palestine AT; a second from Sudan to Nigeria, Cameroon, and from there to further into West and North‐West Africa. This study highlights the necessity to reinforce surveillance at an inter‐regional scale in Africa and Western Asia, in particular along the identified migration routes for the implementation of efficient control measures in the fight against FMD.
Foot-and-mouth disease virus (FMDV) vaccines protect animals from infection by inducing antibodies. The level of neutralising antibody induced in response to vaccination (or infection), as measured by a virus neutralisation test, is an important parameter with regards to the level of protection afforded against subsequent challenge. However, in addition to overall titre, antibody avidity also represents a crucial metric when assessing the protective efficacy of antibodies. In this project we investigated the use of biolayer interferometry (BLI) to measure the avidity of FMDV antibodies to FMDV antigens. Antibodies targeting site I of the FMDV particle were detected using a commercially synthesised biotinylated peptide. In contrast, the entire antigenic landscape of the FMDV particle was represented by biotinylated FMDV capsids. The antigens were loaded onto Octet streptavidin biosensors at an optimal concentration prior to dipping into antibodies. The sera from different animals varied in avidity, reflecting the quantitative differences in avidity that exist between individual animals in response to FMDV vaccines. Interestingly, the Kdis values obtained for site I vs the entire capsid were different, supporting the importance of other sites beyond site I. Similarly, monoclonal antibodies targeting distinct, known antigenic sites on the capsid surface also resulted in different avidities. The BLI methodology reported here offers a useful approach by which to investigate the strength of antibody interactions at specific sites. In conjunction with recombinant technology, BLI will help aid in investigations into the relative importance of the different antigenic sites with regards to inducing a protective response.
Macrophages are derived from hematopoietic progenitor cells throughout the body, are central to inflammatory processes, and participate in innate and adaptive immune responses. In vitro study of macrophages can be undertaken by ex vivo culture from the peritoneum or through differentiation of myeloid bone marrow progenitor cells to form bone marrow-derived macrophages (BMDMs). A common approach to macrophage differentiation from precursors involves the use of conditioned media from L929 cells (LCM). This media is easy to self-produce but suffers from batch variability, and its constituents are undefined. Similarly, Foetal Bovine Serum (FBS) is used to support growth but contains a vast mixture of undefined molecules that may vary between batches. These methods are not adequate for the study of nitric oxide biology and redox mechanisms as they both contain substantial amounts of small molecules that either interfere with redox mechanisms or supplement levels of cofactors, such as tetrahydrobiopterin (BH4), required for the production of NO from inducible nitric oxide synthase (iNOS). In this report, we present an optimized protocol allowing for control of the NO-redox environment by reducing the levels of exogenous biopterin while maintaining conditions suitable for cell growth and differentiation. Tight control of culture media composition helps ensure experimental reproducibility and facilitates accurate interpretation of results. In this protocol, BMDMs were obtained from a GTP cyclohydrolase (GCH)- deficient mouse model. Culture of BMDMs was performed with media containing either (i) conditioned LCM, or (ii) recombinant M-CSF and GM-CSF to produce minimal artifacts while obtaining BH4 and NO-deficient culture conditions - thus allowing for the reproducible study of NO-redox biology and immunometabolism in vitro.
Foot-and-mouth disease (FMD) is a disease of cloven-hoofed livestock caused by FMD virus (FMDV). FMD can be controlled through the use of inactivated vaccines, and it is well established that the protection afforded by FMD vaccines correlates strongly with neutralising antibody titres. However, the overall strength of binding, referred to as avidity, is also an important parameter with respect to the ability of antibodies to neutralise virus infection, and there is evidence that avidity can affect the level of protection afforded by FMDV vaccines. Here, as an alternative to modified enzyme-linked immunosorbent assays (avidity ELISAs) incorporating a chaotropic wash step, we used bio-layer interferometry (BLI) to measure the avidity of bovine polyclonal antibodies against FMDV capsids. We conducted preliminary experiments using recombinant FMDV capsids, as well as peptides representing antigenic loops, to demonstrate that the binding of monoclonal antibodies targeting specific antigenic sites could be detected using BLI. Subsequent experiments using polyclonal sera derived from FMD vaccinated cattle provided evidence of a positive correlation between the neutralising titre of the serum and the avidity as measured by BLI. Furthermore, we observed an increase in BLI avidity, as well as in the titre, in vaccinated animals upon challenge with the live virus.
Viruses can evolve to respond to immune pressures conferred by specific antibodies generated after vaccination and/or infection. In this study, an in vitro system was developed to investigate the impact of serum-neutralising antibodies upon the evolution of a foot-and-mouth disease virus (FMDV) isolate. The presence of sub-neutralising dilutions of specific antisera delayed the onset of virus-induced cytopathic effect (CPE) by up to 44 h compared to the untreated control cultures. Continued virus passage with sub-neutralising dilutions of these sera resulted in a decrease in time to complete CPE, suggesting that FMDV in these cultures adapted to escape immune pressure. These phenotypic changes were associated with three separate consensus-level non-synonymous mutations that accrued in the viral RNA-encoding amino acids at positions VP266, VP280 and VP1155, corresponding to known epitope sites. High-throughput sequencing also identified further nucleotide substitutions within the regions encoding the leader (Lpro), VP4, VP2 and VP3 proteins. While association of the later mutations with the adaptation to immune pressure must be further verified, these results highlight the multiple routes by which FMDV populations can escape neutralising antibodies and support the application of a simple in vitro approach to assess the impact of the humoral immune system on the evolution of FMDV and potentially other viruses.
Autosomal recessive mutations in the PINK1 gene are causal for Parkinson's disease (PD). PINK1 encodes a mitochondrial localized protein kinase that is a master-regulator of mitochondrial quality control pathways. Structural studies to date have elaborated the mechanism of how mutations located within the kinase domain disrupt PINK1 function; however, the molecular mechanism of PINK1 mutations located upstream and downstream of the kinase domain is unknown. We have employed mutagenesis studies to define the minimal region of human PINK1 required for optimal ubiquitin phosphorylation, beginning at residue Ile111. Inspection of the AlphaFold human PINK1 structure model predicts a conserved N-terminal α-helical extension (NTE) domain forming an intramolecular interaction with the C-terminal extension (CTE), which we corroborate using hydrogen/deuterium exchange mass spectrometry of recombinant insect PINK1 protein. Cell-based analysis of human PINK1 reveals that PD-associated mutations (e.g. Q126P), located within the NTE : CTE interface, markedly inhibit stabilization of PINK1; autophosphorylation at Serine228 (Ser228) and Ubiquitin Serine65 (Ser65) phosphorylation. Furthermore, we provide evidence that NTE and CTE domain mutants disrupt PINK1 stabilization at the mitochondrial Translocase of outer membrane complex. The clinical relevance of our findings is supported by the demonstration of defective stabilization and activation of endogenous PINK1 in human fibroblasts of a patient with early-onset PD due to homozygous PINK1 Q126P mutations. Overall, we define a functional role of the NTE : CTE interface towards PINK1 stabilization and activation and show that loss of NTE : CTE interactions is a major mechanism of PINK1-associated mutations linked to PD.
The sequencing of viral genomes provides important data for the prevention and control of foot-and-mouth disease (FMD) outbreaks. Sequence data can be used for strain identification, outbreak tracing, and aiding the selection of the most appropriate vaccine for the circulating strains. At present, sequencing of FMD virus (FMDV) relies upon the time-consuming transport of samples to well-resourced laboratories. The Oxford Nanopore Technologies' MinION portable sequencer has the potential to allow sequencing in remote, decentralised laboratories closer to the outbreak location. In this study, we investigated the utility of the MinION to generate sequence data of sufficient quantity and quality for the characterisation of FMDV serotypes O, A, Asia 1. Prior to sequencing, a universal two-step RT-PCR was used to amplify parts of the 5′UTR, as well as the leader, capsid and parts of the 2A encoding regions of FMDV RNA extracted from three sample matrices: cell culture supernatant, tongue epithelial suspension and oral swabs. The resulting consensus sequences were compared with reference sequences generated on the Illumina MiSeq platform. Consensus sequences with an accuracy of 100% were achieved within 10 and 30 min from the start of the sequencing run when using RNA extracted from cell culture supernatants and tongue epithelial suspensions, respectively. In contrast, sequencing from swabs required up to 2.5 h. Together these results demonstrated that the MinION sequencer can be used to accurately and rapidly characterise serotypes A, O, and Asia 1 of FMDV using amplicons amplified from a variety of different sample matrices.
Antiviral defenses can sense viral RNAs and mediate their destruction. This presents a challenge for host cells since they must destroy viral RNAs while sparing the host mRNAs that encode antiviral effectors. Here, we show that highly upregulated interferon-stimulated genes (ISGs), which encode antiviral proteins, have distinctive nucleotide compositions. We propose that self-targeting by antiviral effectors has selected for ISG transcripts that occupy a less self-targeted sequence space. Following interferon (IFN) stimulation, the CpG-targeting antiviral effector zinc-finger antiviral protein (ZAP) reduces the mRNA abundance of multiple host transcripts, providing a mechanistic explanation for the repression of many (but not all) interferon-repressed genes (IRGs). Notably, IRGs tend to be relatively CpG rich. In contrast, highly upregulated ISGs tend to be strongly CpG suppressed. Thus, ZAP is an example of an effector that has not only selected compositional biases in viral genomes but also appears to have notably shaped the composition of host transcripts in the vertebrate interferome.
Background Foot-and-mouth disease (FMD) is a highly infectious viral disease, recognised to affect animals in the order Artiodactyla. The disease is rarely fatal in adult animals, however high mortality is associated with neonatal and juvenile infection. Case presentation Five puppies died after being fed lamb carcases, the lambs having died during an outbreak of FMD in Iran. Following a post-mortem examination, cardiac tissue from one of the dead puppies was subjected to virus isolation, antigen ELISA, real-time RT-PCR, sequencing and confocal microscopy to assess the presence and characteristics of any FMD virus. The virological and microscopic examination of the cardiac tissue provided evidence of FMD virus replication in the canine heart. Conclusions The data generated in this study demonstrate for the first time that FMD virus can internalise and replicate in dogs and may represent an epidemiologically significant event in FMD transmission, highlighting the dangers of feeding diseased animal carcases to other species. The reporting of this finding may also focus attention on similar disease presentations in dogs in FMD endemic countries allowing a better understanding of the prevalence of such events.
Water Environment ResearchEarly View EDITORIAL Dear WEF, the Academy needs your input to update the Environmental Engineering Body of Knowledge Daniel B. Oerther, Corresponding Author oertherd@mst.edu orcid.org/0000-0002-6724-3205 American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Correspondence Daniel B. Oerther, President-elect, American Academy of Environmental Engineers and Scientists, 147 Old Solomons Island Road, Suite 303, Annapolis, MD 21401, USA. Email: oertherd@mst.eduSearch for more papers by this authorDavid A. Chin, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this authorAndrew Shaw, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this authorDavid A. Vaccari, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this authorWendy Wert, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this author Daniel B. Oerther, Corresponding Author oertherd@mst.edu orcid.org/0000-0002-6724-3205 American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Correspondence Daniel B. Oerther, President-elect, American Academy of Environmental Engineers and Scientists, 147 Old Solomons Island Road, Suite 303, Annapolis, MD 21401, USA. Email: oertherd@mst.eduSearch for more papers by this authorDavid A. Chin, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this authorAndrew Shaw, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this authorDavid A. Vaccari, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this authorWendy Wert, American Academy of Environmental Engineers and Scientists, Annapolis, Maryland, USA Contribution: Conceptualization (equal)Search for more papers by this author First published: 27 September 2021 https://doi.org/10.1002/wer.1647Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinked InRedditWechat No abstract is available for this article. Early ViewOnline Version of Record before inclusion in an issue RelatedInformation