Publications by authors named "Kenneth H Mellits"

During commercial pig production, weaning is a major stressor that disrupts the gut microbiome, compromises intestinal barrier integrity, and increases the susceptibility of piglets to pathogens. This often results in post-weaning diarrhoea (PWD), leading to growth retardation, morbidity, and economic loss. This study investigated the effects of dietary xylo-oligosaccharide (XOS) supplementation on the growth performance and gut health of 216 piglets with naturally occurring PWD.

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Article Synopsis
  • Equine rotavirus species A genotypes G3P[12] and G14P[12] are major causes of foal diarrhea, impacting the equine industry economically and showing potential for zoonotic transmission to humans, as seen in past outbreaks of severe gastroenteritis in children.
  • Traditional cell culture methods for isolating rotaviruses are ineffective for ERVA, but researchers successfully isolated both strains using engineered cell lines with reduced antiviral immunity, revealing genetic similarities and differences that affect their ability to invoke immune responses.
  • The study highlights limited cross-neutralization between G3P[12] and G14P[12], which explains increased diarrhea outbreaks in foals despite immunity from vaccines targeting G3P[12], paving
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Introduction: Rotavirus A is a major cause of acute dehydrating diarrhea in neonatal pigs resulting in significant mortality, morbidity, reduced performance and economic loss. Commercially available prebiotic galacto-oligosaccharides are similar to those of mammalian milk and stimulate the development of the microbiota and immune system in neonates. Little is known about the effects of supplementing sows' diets with galacto-oligosaccharides during gestation.

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Poorly performing piglets receiving commercial milk replacers do not benefit from the naturally occurring probiotic galacto-oligosaccharides otherwise found in sow milk. Study objectives were to investigate the effects of complete milk replacer supplemented with galacto-oligosaccharides on the microbiome, gut architecture and immunomodulatory goblet cell expression of poorly performing piglets that could benefit from milk replacement feeding when separated from sows and housed with fit siblings in environmentally controlled pens. The study is novel in that it is one of the first to investigate the effects of supplementing complete milk replacer with galacto-oligosaccharides in poorly performing piglets.

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The primary objective of this study was to investigate if common colonic community indicators could be identified from the microbiota of 22-day-old suckling pigs in repeated small-scale trials. A total of three separate trials were conducted at different times in the same year and facility with genetically similar animals. Colonic samples were collected from four pigs in each trial and the microbiome composition assessed by 16s rRNA gene sequencing.

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The struggle to control the COVID-19 pandemic is made challenging by the emergence of virulent SARS-CoV-2 variants. To gain insight into their replication dynamics, emergent Alpha (A), Beta (B) and Delta (D) SARS-CoV-2 variants were assessed for their infection performance in single variant- and co-infections. The effectiveness of thapsigargin (TG), a recently discovered broad-spectrum antiviral, against these variants was also examined.

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The long-term control strategy of SARS-CoV-2 and other major respiratory viruses needs to include antivirals to treat acute infections, in addition to the judicious use of effective vaccines. Whilst COVID-19 vaccines are being rolled out for mass vaccination, the modest number of antivirals in use or development for any disease bears testament to the challenges of antiviral development. We recently showed that non-cytotoxic levels of thapsigargin (TG), an inhibitor of the sarcoplasmic/endoplasmic reticulum (ER) Ca ATPase pump, induces a potent host innate immune antiviral response that blocks influenza A virus replication.

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An entirely plasmid-based reverse genetics (RG) system was recently developed for rotavirus (RV), opening new avenues for in-depth molecular dissection of RV biology, immunology, and pathogenesis. Several improvements to further optimize the RG efficiency have now been described. However, only a small number of individual RV strains have been recovered to date.

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Pigs are evidently more resistant to avian than swine influenza A viruses, mediated in part through frontline epithelial cells and alveolar macrophages (AM). Although porcine AM (PAM) are crucial in influenza virus control, their mode of control is unclear. To gain insight into the possible role of PAM in the mediation of avian influenza virus resistance, we compared the host effects and replication of two avian (H2N3 and H6N1) and three mammalian (swine H1N1, human H1N1 and pandemic H1N1) influenza viruses in PAM.

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Group A rotaviruses (GARV) are a significant cause of enteritis in young pigs. The aim of this study was to extend our understanding of the molecular epidemiology of porcine GARV in the UK by investigating the genetic diversity of GARV on a conventional farrow-to-finish farm. Faecal samples were obtained from six batches of pigs in 2009 and 8 batches in 2010, when the pigs were 2, 3 (time point omitted in 2009), 4, 5, 6 and 8 weeks of age.

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Unlabelled: Rotavirus is an enteric pathogen that causes morbidity and mortality in young mammals, including pigs. Outbreaks of rotavirus on commercial farms have a significant economic impact in terms of losses in production. Effective cleaning and disinfection along with good farm management can reduce rotavirus contamination in the environment, and decrease the chance of outbreaks of disease.

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Rotavirus is endemic in pig farms where it causes a loss in production. This study is the first to characterise porcine rotavirus circulating in UK pigs. Samples from diarrheic pigs with rotavirus enteritis obtained between 2010 and 2012 were genotyped in order to determine the diversity of group A rotavirus (GARV) in UK pigs.

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Exposure to interferon results in the rapid transcriptional induction of genes, many of which function to create an antiviral environment in potential host cells. For the majority of adenoviruses, replication is unaffected by the actions of interferon. It has previously been shown, using non-gastrointestinal cells, that the species F human adenoviruses are sensitive to the action of interferon.

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Campylobacter jejuni activates the host transcription factor NF-kappaB that regulates the expression of a number of genes involved in the inflammatory response to bacterial infection. Signaling pathways leading to NF-kappaB by pathogens and/or their products include transmembrane Toll-like receptors (TLRs) and intracellular receptors nucleotide-binding oligomerization domain proteins (Nods). This study was carried out to investigate the role of TLRs (TLR2 and TLR4) and Nods (Nod1 and Nod2) receptors in mediating NF-kappaB activation by C.

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Background: Campylobacter jejuni, the commonest cause of bacterial diarrhoea worldwide, can also induce colonic inflammation. To understand how a previously identified heat stable component contributes to pro-inflammatory responses we used microarray and real-time quantitative PCR to investigate the transcriptional response to a boiled cell extract of Campylobacter jejuni NCTC 11168.

Results: RNA was extracted from the human colonocyte line HCA-7 (clone 29) after incubation for 6 hours with Campylobacter jejuni boiled cell extract and was used to probe the Affymetrix Human Genome U133A array.

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Human enteric adenoviruses propagate poorly in conventional human cell lines used to grow other adenovirus serotypes. As human enteric adenoviruses have a defect in counteracting the cellular interferon (IFN) response in cell culture, to aid in growth of the virus, a 293-based cell line defective in its ability to respond to IFN was constructed. This cell line (293-SV5/V) constitutively expresses V-protein of the paramyxovirus Simian virus 5, which degrades the signal transducer and activator of transcription 1 (STAT1) and thereby prevents the STAT1-mediated IFN response.

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Enteropathogenic Escherichia coli (EPEC) cause infantile diarrhoea and are characterized by their ability to produce attaching and effacing lesions on the surface of intestinal epithelial cells. EPEC employ a filamentous type III secretion system to deliver effector molecules that subvert mammalian cell function to generate actin- and cytokeratin-rich pedestals beneath adherent bacteria. Tir is a major effector protein that is delivered to the plasma membrane of the eukaryotic cell where it acts as the receptor for the bacterial adhesin intimin.

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Campylobacter jejuni is a food-borne pathogen responsible for infectious enterocolitis. The early-response transcription factor NF-kappa B triggers the expression of genes associated with cellular immune and inflammatory responses. Co-incubation of HeLa cells with viable C.

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