Imputed genomes and haplotype-based analyses of the Picts of early medieval Scotland reveal fine-scale relatedness between Iron Age, early medieval and the modern people of the UK.

There are longstanding questions about the origins and ancestry of the Picts of early medieval Scotland (ca. 300-900 CE), prompted in part by exotic medieval origin myths, their enigmatic symbols and inscriptions, and the meagre textual evidence. The Picts, first mentioned in the late 3rd century CE resisted the Romans and went on to form a powerful kingdom that ruled over a large territory in northern Britain. In the 9th and 10th centuries Gaelic language, culture and identity became dominant, transforming the Pictish realm into Alba, the precursor to the medieval kingdom of Scotland. To date, no comprehensive analysis of Pictish genomes has been published, and questions about their biological relationships to other cultural groups living in Britain remain unanswered. Here we present two high-quality Pictish genomes (2.4 and 16.5X coverage) from central and northern Scotland dated from the 5th-7th century which we impute and co-analyse with >8,300 previously published ancient and modern genomes. Using allele frequency and haplotype-based approaches, we can firmly place the genomes within the Iron Age gene pool in Britain and demonstrate regional biological affinity. We also demonstrate the presence of population structure within Pictish groups, with Orcadian Picts being genetically distinct from their mainland contemporaries. When investigating Identity-By-Descent (IBD) with present-day genomes, we observe broad affinities between the mainland Pictish genomes and the present-day people living in western Scotland, Wales, Northern Ireland and Northumbria, but less with the rest of England, the Orkney islands and eastern Scotland-where the political centres of Pictland were located. The pre-Viking Age Orcadian Picts evidence a high degree of IBD sharing across modern Scotland, Wales, Northern Ireland, and the Orkney islands, demonstrating substantial genetic continuity in Orkney for the last ~2,000 years. Analysis of mitochondrial DNA diversity at the Pictish cemetery of Lundin Links (n = 7) reveals absence of direct common female ancestors, with implications for broader social organisation. Overall, our study provides novel insights into the genetic affinities and population structure of the Picts and direct relationships between ancient and present-day groups of the UK.

Dissecting the molecular diversity and commonality of bovine and human treponemes identifies key survival and adhesion mechanisms.

Here, we report the first complete genomes of three cultivable treponeme species from bovine digital dermatitis (DD) skin lesions, two comparative human treponemes, considered indistinguishable from bovine DD species, and a bovine gastrointestinal (GI) treponeme isolate. Key genomic differences between bovine and human treponemes implicate microbial mechanisms that enhance knowledge of how DD, a severe disease of ruminants, has emerged into a prolific, worldwide disease. Bovine DD treponemes have additional oxidative stress genes compared to nearest human-isolated relatives, suggesting better oxidative stress tolerance, and potentially explaining how bovine strains can colonize skin surfaces. Comparison of both bovine DD and GI treponemes as well as bovine pathogenic and human non-pathogenic saprophyte Treponema phagedenis strains indicates genes encoding a five-enzyme biosynthetic pathway for production of 2,3-diacetamido-2,3-dideoxy-d-mannuronic acid, a rare di-N-acetylated mannuronic acid sugar, as important for pathogenesis. Bovine T. phagedenis strains further differed from human strains by having unique genetic clusters including components of a type IV secretion system and a phosphate utilisation system including phoU, a gene associated with osmotic stress survival. Proteomic analyses confirmed bovine derived T. phagedenis exhibits expression of PhoU but not the putative secretion system, whilst the novel mannuronic acid pathway was expressed in near entirety across the DD treponemes. Analysis of osmotic stress response in water identified a difference between bovine and human T. phagedenis with bovine strains exhibiting enhanced survival. This novel mechanism could enable a selective advantage, allowing environmental persistence and transmission of bovine T. phagedenis. Finally, we investigated putative outer membrane protein (OMP) ortholog families across the DD treponemes and identified several families as multi-specific adhesins capable of binding extra cellular matrix (ECM) components. One bovine pathogen specific adhesin ortholog family showed considerable serodiagnostic potential with the Treponema medium representative demonstrating considerable disease specificity (91.6%). This work has shed light on treponeme host adaptation and has identified candidate molecules for future diagnostics, vaccination and therapeutic intervention.

Treponema spp. spirochetes and keratinopathogenic fungi isolated from keratomas in donkeys.

Keratoma is an aberrant keratin mass thought to originate from epidermal horn-producing cells interposed between the stratum medium of the hoof wall and the underlying third phalanx. The cause is unknown, although the presence of keratomas is frequently associated with chronic irritation, focal infection, or trauma. A total of 167 donkeys with keratomas were presented in this study. The diagnosis of a keratoma was based on clinical signs, radiography, and histopathologic examination. Surgical excision was attempted on all donkeys with lameness unless euthanasia was advised. Histopathologic examination, including Giemsa, periodic acid Schiff, and Young's silver special histochemical stains, was performed and showed the presence of fungal hyphae and spirochete bacteria within the degenerate keratin. Polymerase chain reaction (PCR) for treponeme bacteria was performed on 10 keratoma lesions and 9 healthy pieces of hoof (controls). All healthy donkey tissues were negative for the 3 recognized digital dermatitis (DD) treponeme phylogroups, whereas 3 of 10 (30%) donkey keratoma samples were positive for one of the DD treponeme phylogroups. Routine fungal culture and PCR for fungi were performed on 8 keratoma lesions and 8 healthy pieces of hoof (controls). Keratinopathogenic fungi were detected in 1 of 8 (12.5%) keratomas, while only non-keratinopathogenic, environmental fungi were detected in 8 control healthy hoof samples. This is the first time the DD treponemes phylogroup and keratinopathogenic fungi have been detected in keratomas. Further studies are required to assess the significance of this finding.

Prospective cohort study of neurodevelopmental outcomes following extreme neonatal hyperbilirubinaemia in Australia.

AIM: This study aimed to establish the incidence and nature of neurodevelopmental outcomes following extreme neonatal hyperbilirubinaemia in an Australian cohort. METHODS: A prospective cohort study of neurodevelopmental outcomes up to 3 years of age of infants born between 2010 and 2013 at ≥34 weeks gestation, with total serum bilirubin ≥450 µmol/L and/or clinical signs of acute bilirubin encephalopathy. Outcome measures comprised neurological examination, Bayley Scales of Infant and Toddler Development, 3rd edition and Ages and Stages Questionnaire, 3rd edition. RESULTS: The Australian estimated incidence of kernicterus is 0.35 per 100 000 live births. Within the follow-up cohort of 26, three children have clinical neurodevelopmental impairment: one has gross motor function classification system level 4 cerebral palsy, audiological deficiency and visual impairment; the second has gross motor function classification system level 1 cerebral palsy and the third has global developmental delay with autism spectrum disorder. Mean Bayley Scales of Infant and Toddler Development, 3rd edition scores were: cognition 10.3 (SD 1.5), receptive communication 9.4 (SD 1.8), expressive communication 9.2 (SD 2.4), fine motor 10.4 (SD 2.6) and gross motor 9.2 (SD 2.3). CONCLUSION: The Australian national rate of kernicterus compares favourably with global estimates. Future preventative strategies in this context include universal neonatal hyperbilirubinaemia assessment and mandated adverse outcome reporting and investigation.

Survival of bovine digital dermatitis treponemes in conditions relevant to the host and farm environment.

OBJECTIVES: Bovine digital dermatitis (BDD), a painful infectious foot disease in dairy cattle, endemic in many countries worldwide, causes substantial economic and welfare impacts. Treponema spp. are considered key to BDD pathogenesis. To aid infection reservoir identification and control measure development, survival of BDD treponemes was investigated in different temperatures (4, 12, 20, 37, 45 and 60 °C), pH values (5-9.0), dairy cattle faeces and bedding types: straw shavings, sand, sand containing 5% lime (w/w) and recycled manure solids (RMS). METHODS: A turbidity microplate methodology was adapted to measure pH impact on growth. Survival of BDD treponemes for the different conditions were assessed by sub-cultures of microcosms over different time points. RESULTS: BDD treponemes remained viable between 4 and 37 °C and pH 5.5 and 9.0 under anaerobic conditions. In sterile faecal microcosms, incubated aerobically at 12 °C, BDD treponemes remained viable for a median of 1 day (15 min - 6 day range). Variation in duration of survival and ability to grow was observed between phylogroups and strains. In aerobic microcosms, T. phagedenis T320A remained viable for the full 7 days in sand, 6 days in sawdust, 5 days in RMS, but was not viable after 15 min in straw or sand containing 5% (w/w) lime. CONCLUSIONS: Treponeme survival conditions identified here should enhance future BDD infection reservoir surveys and enable control measures. Of note, straw or sand containing 5% (w/w) lime should be assessed in BDD field trials. Finally, these data indicate BDD treponemes exhibit characteristics of facultative anaerobes.

Measuring the impact of bovine digital dermatitis research on knowledge and practice of biosecurity during cattle foot-trimming.

This research communication reports the results from questionnaires used to identify the impact of recent research into the disinfection of cattle foot-trimming equipment to prevent bovine digital dermatitis (BDD) transmission on (a) biosecurity knowledge and (b) hygiene practice of foot health professionals. An initial questionnaire found that more than half of participating farmers, veterinary surgeons and commercial foot-trimmers were not considering hand or hoof-knife hygiene in their working practices. The following year, after the release of a foot-trimming hygiene protocol and a comprehensive knowledge exchange programme by the University of Liverpool, a second survey showed 35/80 (43.8%) farmers, veterinary surgeons and commercial foot-trimmers sampled considered they were now more aware of the risk of spreading BDD during foot- trimming. Furthermore, 36/80 (45.0%) had enhanced their hygiene practice in the last year, impacting an estimated 1383 farms and 5130 cows trimmed each week. Participants who reported having seen both the foot-trimming hygiene protocol we developed with AHDB Dairy and other articles about foot-trimming hygiene in the farming and veterinary press, were significantly more likely to have changed their working practices. Difficulties accessing water and cleaning facilities on farms were identified as the greatest barrier to improving biosecurity practices. Participants' preferred priority for future research was continued collection of evidence for the importance and efficacy of good foot-trimming hygiene practices.

Treponema rectale sp. nov., a spirochete isolated from the bovine rectum.

A Gram-stain-negative, obligatory anaerobic spirochete, CHPAT, was isolated from the rectal tissue of a Holstein-Friesian cow. On the basis of 16S rRNA gene comparisons, CHPAT was most closely related to the human oral spirochete, Treponema parvum, with 88.8 % sequence identity. Further characterisation on the basis of recA gene sequence analysis, cell morphology, pattern of growth and physiological profiling identified marked differences with respect to other recognised species of the genus Treponema. Microscopically, the helical cells measured approximately 1-5 µm long and 0.15-0.25 µm wide, with two to five irregular spirals. Transmission electron microscopy identified four periplasmic flagella in a 2 : 4 : 2 arrangement. CHPAT grew independently of serum, demonstrated no evidence of haemolytic activity and possessed an in vitro enzyme activity profile that is unique amongst validly named species of the genus Treponema, exhibiting C4 esterase, α-galactosidase and ß-galactosidase activity. Taken together, these data indicate that CHPAT represents a novel species of the genus Treponema, for which the name Treponema rectale is proposed. The type strain of Treponema rectale is CHPAT (=DSM 103679T=NCTC 13848T).

Treponema ruminis sp. nov., a spirochaete isolated from the bovine rumen.

A novel bacterium, strain Ru1T, was encountered during a survey of spirochaetes living in the gastrointestinal tract of ruminants. Comparative analysis of 16S rRNA gene sequence data indicated that strain Ru1T clustered within the genus Treponemabut shared at most 86.1 % sequence similarity with other recognised species of the genus Treponema. Further phylogenetic analysis based on partial recombinase A (recA) gene sequence comparisons, together with phenotypic characterization, also demonstrated the divergence of strain Ru1T from other recognised species of the genus Treponema. Microscopically, strain Ru1T appeared as a very small, highly motile, helical spirochaete with eight periplasmic flagella in a 4 : 8 : 4 arrangement. It exhibited C8 esterase lipase, leucine arylamidase, ß-galactosidase and ß-glucosidase activity. A distinctive, serum-independent growth pattern was also observed, characterized by colonies with an absence of the local haemolysis that is typical of many pathogenic treponemes. On the basis of these data, strain Ru1T is considered to represent a novel species of the genus Treponema, for which the name Treponema ruminis sp. nov. is proposed. The type strain is Ru1T (=DSM 103462T=NCTC 13847T).

Multilocus Sequence Typing of Pathogenic Treponemes Isolated from Cloven-Hoofed Animals and Comparison to Treponemes Isolated from Humans.

UNLABELLED: Treponema species are implicated in many diseases of humans and animals. Digital dermatitis (DD) treponemes are reported to cause severe lesions in cattle, sheep, pigs, goats, and wild elk, causing substantial global animal welfare issues and economic losses. The fastidiousness of these spirochetes has previously precluded studies investigating within-phylogroup genetic diversity. An archive of treponemes that we isolated enabled multilocus sequence typing to quantify the diversity and population structure of DD treponemes. Isolates (n = 121) were obtained from different animal hosts in nine countries on three continents. The analyses herein of currently isolated DD treponemes at seven housekeeping gene loci confirm the classification of the three previously designated phylogroups: the Treponema medium, Treponema phagedenis, and Treponema pedis phylogroups. Sequence analysis of seven DD treponeme housekeeping genes revealed a generally low level of diversity among the strains within each phylogroup, removing the need for the previously used "-like" suffix. Surprisingly, all isolates within each phylogroup clustered together, regardless of host or geographic origin, suggesting that the same sequence types (STs) can infect different animals. Some STs were derived from multiple animals from the same farm, highlighting probable within-farm transmissions. Several STs infected multiple hosts from similar geographic regions, identifying probable frequent between-host transmissions. Interestingly, T. pedis appears to be evolving more quickly than the T. medium or T. phagedenis DD treponeme phylogroup, by forming two unique ST complexes. The lack of phylogenetic discrimination between treponemes isolated from different hosts or geographic regions substantially contrasts with the data for other clinically relevant spirochetes. IMPORTANCE: The recent expansion of the host range of digital dermatitis (DD) treponemes from cattle to sheep, goats, pigs, and wild elk, coupled with the high level of 16S rRNA gene sequence similarity across hosts and with human treponemes, suggests that the same bacterial species can cause disease in multiple different hosts. This multilocus sequence typing (MLST) study further demonstrates that these bacteria isolated from different hosts are indeed very similar, raising the potential for cross-species transmission. The study also shows that infection spread occurs frequently, both locally and globally, suggesting transmission by routes other than animal-animal transmission alone. These results indicate that on-farm biosecurity is important for controlling disease spread in domesticated species. Continued surveillance and vigilance are important for ascertaining the evolution and tracking any further host range expansion of these important pathogens.

Isolation of digital dermatitis treponemes from cattle hock skin lesions.

BACKGROUND: Bovine hock lesions present a serious welfare and production issue on dairy farms worldwide. Current theories suggest that trauma is an important factor in the formation of hock lesions, although infection may also play a role in increasing their severity and duration. HYPOTHESIS: Digital dermatitis (DD) lesions in dairy cows are strongly associated with specific treponeme bacteria which are opportunistic invaders of other skin regions. Hock lesions were tested to ascertain if they too contained treponemes. ANIMALS: Swab and tissue samples were taken from hock lesions from two farms in South West England. METHODS: Hock lesions were classified into two categories: open lesions, which were often bleeding and ulcerated, or were encrusted; and closed lesions, which were classified as hair loss with no skin breakage. PCR assays and bacterial isolation were used to detect treponemes in hock lesions. RESULTS: All three phylogroups of digital dermatitis treponemes were detectable and isolated from open hock lesions only, with closed lesions showing no evidence of treponeme infection, either by PCR or bacterial culture. When analysed by 16S rRNA gene sequencing, the cultured treponeme DNA showed complete homology or was very similar to that found in foot lesions. Additionally, skin swabs from near the open hock wounds were also positive by PCR assay and isolation for the DD treponemes. CONCLUSIONS AND CLINICAL IMPORTANCE: Identification of the contribution of these infectious agents will allow for more optimal treatments to be developed that reduce the prevalence and healing times of both hock and DD lesions.

In vitro susceptibility of contagious ovine digital dermatitis associated Treponema spp. isolates to antimicrobial agents in the UK.

BACKGROUND: Contagious ovine digital dermatitis (CODD) is an important cause of infectious lameness in sheep in the UK and Ireland and has a severe impact on the welfare of affected individuals. The three treponemal phylogroups Treponema medium/Treponema vincentii-like, Treponema phagedenis-like and Treponema pedis spirochaetes have been associated with clinical CODD lesions and are considered to be a necessary cause of disease. There are scant data on the antimicrobial susceptibility of the treponemes cultured from CODD lesions. OBJECTIVE: The aim of this study was to determine in vitro the miniumum inhibitory concentration/ minimum bactericidal concentration (MIC/MBC) of antimicrobials used in the sheep industry for isolates of the three CODD associated treponeme phylogroups T. medium/T. vincentii-like, T. phagedenis-like and T. pedis. ANIMALS: Twenty treponeme isolates; from 19 sheep with clinical CODD lesions. METHODS: A microdilution method was used to determine in vitro the MIC/MBC of 10 antimicrobial agents for 20 treponeme isolates (five T. medium/T. vincentii-like, 10 T. phagedenis-like and five T. pedis). The antimicrobials tested were penicillin G, amoxicillin, oxytetracycline, tilmicosin, lincomycin, spectinomycin, tylosin, tildipirosin, tulathromycin and gamithromycin. RESULTS: The treponeme isolates tested showed low MICs and MBCs to all 10 antimicrobials tested. They were most susceptible to gamithromycin and tildipirosin (MIC90: 0.0469 mg/L), and were least susceptible to lincomycin, spectinomycin and oxytetracycline (MIC90: 48 mg/L, 24 mg/L and 3 mg/L, respectively). CONCLUSIONS: These data are comparable to in vitro antimicrobial susceptibility data for treponemes cultured from bovine digital dermatitis lesions. Dependent on local licensing, penicillin and tilmicosin appear to be the best candidates for future in vivo studies.

Detection and molecular characterization of Escherichia coli CTX-M-15 and Klebsiella pneumoniae SHV-12 ß-lactamases from bovine mastitis isolates in the United Kingdom.

Recent reports raised concerns about the role that farm stock may play in the dissemination of extended-spectrum ß-lactamase (ESBL)-producing bacteria. This study characterized the ESBLs in two Escherichia coli and three Klebsiella pneumoniae subsp. pneumoniae isolates from cases of clinical bovine mastitis in the United Kingdom. Bacterial culture and sensitivity testing of bovine mastitic milk samples identified Gram-negative cefpodoxime-resistant isolates, which were assessed for their ESBL phenotypes. Conjugation experiments and PCR-based replicon typing (PBRT) were used for characterization of transferable plasmids. E. coli isolates belonged to sequence type 88 (ST88; determined by multilocus sequence typing) and carried blaCTX-M-15 and blaTEM-1, while K. pneumoniae subsp. pneumoniae isolates carried blaSHV-12 and blaTEM-1. Conjugation experiments demonstrated that blaCTX-M-15 and blaTEM-1 were carried on a conjugative plasmid in E. coli, and PBRT identified this to be an IncI1 plasmid. The resistance genes were nontransferable in K. pneumoniae subsp. pneumoniae isolates. Moreover, in the E. coli isolates, an association of ISEcp1 and IS26 with blaCTX-M-15 was found where the IS26 element was inserted upstream of both ISEcp1 and the blaCTX-M promoter, a genetic arrangement highly similar to that described in some United Kingdom human isolates. We report the first cases in Europe of bovine mastitis due to E. coli CTX-M-15 and also of bovine mastitis due to K. pneumoniae subsp. pneumoniae SHV-12 ß-lactamases in the United Kingdom. We also describe the genetic environment of blaCTX-M-15 and highlight the role that IncI1 plasmids may play in the spread and dissemination of ESBL genes, which have been described in both human and cattle isolates.

Molecular Screening for Digital Dermatitis-Associated Treponemes in Bovine Ischaemic Teat Necrosis Lesions and Milk in Dairy Cattle.

Bovine ischaemic teat necrosis (ITN) is a disease affecting the skin of the teats of dairy cows with an unknown aetiopathogenesis. Digital dermatitis (DD)-associated treponemes have previously been suggested as a potential aetiological agent in ITN, although the sample size was small. The current study, using established PCR techniques, aimed to examine the association with the presence of DD-associated treponemes in a large number of ITN samples from a wider geographical area, and surveyed the potential of milk as an infection reservoir. From 95 ITN lesions, 35.8% (n = 34) were positive for at least one DD-associated treponeme compared with only 5.6% (n = 1) of 18 non-lesioned teats from cows with ITN lesions on a different teat using a nested PCR approach. All 10 age- and production-matched control cows were negative for DD-associated treponemes via PCR. No DD-associated treponemes could be detected from foremilk of cows with (n = 19) and without (n = 31) a DD lesion on the hind feet. DD-associated treponemes could be detected via PCR after incubation in milk for up to 2 h. Therefore, milk does not appear to be a competent reservoir for transmission of DD-associated treponemes. Moreover, in the current study DD-associated treponemes were only detected in a subset of ITN samples, so it is unlikely these opportunistic skin-associated pathogens are the major or sole agent of ITN.

The incidence, duration, risk factors, and age-based variation of missed opportunities to diagnose pertussis: A population-based cohort study.

OBJECTIVE: To estimate the incidence, duration and risk factors for diagnostic delays associated with pertussis. DESIGN: We used longitudinal retrospective insurance claims from the Marketscan Commercial Claims and Encounters, Medicare Supplemental (2001-2020), and Multi-State Medicaid (2014-2018) databases. SETTING: Inpatient, emergency department, and outpatient visits. PATIENTS: The study included patients diagnosed with pertussis (International Classification of Diseases [ICD] codes) and receipt of macrolide antibiotic treatment. METHODS: We estimated the number of visits with pertussis-related symptoms before diagnosis beyond that expected in the absence of diagnostic delays. Using a bootstrapping approach, we estimated the number of visits representing a delay, the number of missed diagnostic opportunities per patient, and the duration of delays. Results were stratified by age groups. We also used a logistic regression model to evaluate potential factors associated with delay. RESULTS: We identified 20,828 patients meeting inclusion criteria. On average, patients had almost 2 missed opportunities prior to diagnosis, and delay duration was 12 days. Across age groups, the percentage of patients experiencing a delay ranged from 29.7% to 37.6%. The duration of delays increased considerably with age from an average of 5.6 days for patients aged <2 years to 13.8 days for patients aged ≥18 years. Factors associated with increased risk of delays included emergency department visits, telehealth visits, and recent prescriptions for antibiotics not effective against pertussis. CONCLUSIONS: Diagnostic delays for pertussis are frequent. More work is needed to decrease diagnostic delays, especially among adults. Earlier case identification may play an important role in the response to outbreaks by facilitating treatment, isolation, and improved contact tracing.

Predicting use of a gait-stabilizing device using a Wii Balance Board.

Gait-stabilizing devices (GSDs) are effective at preventing falls, but people are often reluctant to use them until after experiencing a fall. Inexpensive, convenient, and effective methods for predicting which patients need GSDs could help improve adoption. The purpose of this study was to determine if a Wii Balance Board (WBB) can be used to determine whether or not patients use a GSD. We prospectively recruited participants ages 70-100, some who used GSDs and some who did not. Participants first answered questions from the Modified Vulnerable Elders Survey, and then completed a grip-strength test using a handgrip dynamometer. Finally, they were asked to complete a series of four 30-second balance tests on a WBB in random order: (1) eyes open, feet apart; (2) eyes open, feet together; (3) eyes closed, feet apart; and (4) eyes closed, feet together. The four-test series was repeated a second time in the same random order. The resulting data, represented as 25 features extracted from the questionnaires and the grip test, and data from the eight balance tests, were used to predict a subject's GSD use using generalized functional linear models based on the Bernoulli distribution. 268 participants were consented; 62 were missing data elements and were removed from analysis; 109 were not GSD users and 97 were GSD users. The use of velocity and acceleration information from the WBB improved upon predictions based solely on grip strength, demographic, and survey variables. The WBB is a convenient, inexpensive, and easy-to-use device that can be used to recommend whether or not patients should be using a GSD.

An oral commensal attenuates Pseudomonas aeruginosa-induced airway inflammation and modulates nitrite flux in respiratory epithelium.

IMPORTANCE: Respiratory infections are a leading cause of morbidity and mortality in people with cystic fibrosis (CF). These infections are polymicrobial in nature with overt pathogens and other colonizing microbes present. Microbiome data have indicated that the presence of oral commensal bacteria in the lungs is correlated with improved outcomes. We hypothesize that one oral commensal, Streptococcus parasanguinis, inhibits CF pathogens and modulates the host immune response. One major CF pathogen is Pseudomonas aeruginosa, a Gram-negative, opportunistic bacterium with intrinsic drug resistance and an arsenal of virulence factors. We have previously shown that S. parasanguinis inhibits P. aeruginosa in vitro in a nitrite-dependent manner through the production of reactive nitrogen intermediates. In this study, we demonstrate that while this mechanism is evident in a cell culture model of the CF airway, an alternative mechanism by which S. parasanguinis may improve outcomes for people with CF is through immunomodulation.

A reduced potential for lameness bacterial transmission by Lucilia sericata larvae and flies through metamorphosis.

Lameness in sheep is one of the most serious issues on farms in the UK and worldwide, affecting over 90% of all UK sheep flocks. Despite its severity and prevalence, there are knowledge gaps regarding transmission routes of bacterial pathogens associated with infectious lameness in sheep. As larvae of Lucilia sericata are commonly found on foot lesions on lame sheep, it was hypothesised that the flies or their larvae could harbour lameness associated bacteria. This study examined the gut contents of larvae obtained from the foot lesions of lame sheep and compared them to control larvae collected from infested cat food on the same farm. Of particular interest, were the presence of three different bacterial genera associated with lameness; Fusobacterium necrophorum, Dichelobacter nodosus and Treponema spp., for which viability was also investigated. Larvae were cultured In vitro and some allowed to metamorphose into flies before specific PCR assays were carried out on the gut contents. Results showed a significant association between the bacteria on the feet of the sheep and those within the larvae. Although the gut contents of all larvae found on sheep feet contained one or more of the lameness bacteria, none of the bacteria were recovered from the adult flies, suggesting a level of gut remodelling during metamorphosis. Interestingly, Treponema spp. and Fusobacterium spp. were viable when isolated from gut contents of larvae. Maintenance of infection from larvae to fly did not occur. However, it still remains important to control both disease and insect populations of farms to maintain animal welfare.

Lennox Gastaut Syndrome - A strategic shift in diagnosis over time?

BACKGROUND: Lennox Gastaut Syndrome (LGS) is an epilepsy syndrome presenting in childhood, classically characterised by a triad of cognitive or developmental impairment, multiple seizure types and EEG features of slow-spike waves (SWW), with or without paroxysmal fast activity (PFA) in sleep. There is increasing scientific opinion in favour of a less rigid approach to LGS diagnosis and this clinical audit attempts to shed light on how the LGS diagnostic criteria used may have changed over time, in a large tertiary paediatric neurology unit (Great Ormond Street Hospital (GOSH), London, UK). METHODS: Electronic patient records were reviewed for patients with a diagnosis of LGS made at GOSH within two time periods, 2014-2017 and 2018-2021. Patient demographics, aetiology, clinical features, EEG features, investigation results and medications were reviewed. Findings were compared against the International League Against Epilepsy (ILAE) Diagnostic Manual criteria for LGS diagnosis (the classical triad plus PFA in sleep). Existing GOSH data regarding total number of new epilepsy referrals to GOSH and ICD10 codes (including all epilepsy and epilepsy syndromes) per year were also used to review LGS diagnoses as proportions of new epilepsy referrals and total number of epilepsy diagnoses. RESULTS: 5 LGS diagnoses were made in 2014-2017 compared to 40 diagnoses made in 2018-2021. There was a steep increase in the number of LGS diagnoses and LGS diagnoses as a proportion of total epilepsy diagnoses in the last 4 years, coinciding with the licensing of cannabidiol for management of LGS in the UK in 2018. There was a much less marked increase in LGS diagnoses as a proportion of epilepsy referrals from 2018 (and an as yet unexplained high proportion in 2014). The 2014-17 cohort fit a more classical LGS diagnostic criteria of the triad plus presence of PFA on sleep EEG (100% in 2014-17 vs 68% in 2018-21), with a more classical preceding history of infantile spasms (80% in 2014-17 vs 23% in 2018-21). Common seizure types were similar in both groups and a male preponderance was also noted in both groups. Cannabidiol use in LGS patients has also increased over time, all prescribed after 2018. CONCLUSIONS: Despite the limitations of the small numbers of patients in each group, the results of this clinical audit are in keeping with changing clinical trends in favour of a broader LGS diagnostic criteria. The combination of this less rigid diagnostic criteria, the steep increase in diagnosis seen from 2018 onwards (coinciding with UK cannabidiol licencing for LGS in 2018) and the fact that most of the LGS patients in both groups are currently prescribed cannabidiol, may reflect a strategic shift in attitude towards LGS diagnosis or an increase in referrals for LGS, possibly to help facilitate access to novel treatments.

An Observational Study Investigating Potential Risk Factors and Economic Impact for Bovine Ischaemic Teat Necrosis on Dairy Farms in Great Britain.

Bovine ischaemic teat necrosis (ITN) is an emerging disease of unknown aetiology that affects the teats of dairy cattle. It causes economic and animal welfare issues with many animals being culled. No effective treatments or epidemiological data to inform control strategies are currently available. The aim of this observational study was to investigate farmer-reported experiences and identify potential farm-level risk factors. In January 2018, a questionnaire was sent to a random sample of 1,855 Great Britain (GB) dairy farmers. A usable response rate of 12.3% was obtained. Fifty-one per cent [95% confidence interval (CI): 44.4-57.8%] of farmers reported having experienced ITN on their farm between 1985 and 2018. Rising numbers of farms indicated that ITN is an emerging disease with 46.3% of farmers reporting the first case in the 3 years up to 2018. At the animal level, 47.3% (95% CI: 38.7-55.9%) of the cases occurred during the first lactation and 78.9% (95% CI: 75.2-82.6%) within the first 90 days in milk. Only 20.8% (95% CI: 15.9-26.4%) of the cases were reported to recover, whereas 22.8% (95% CI: 17.8-28.5%) of the cases required culling. The remaining cases experienced complications such as loss of a teat and/or mastitis. From these data, the cost of ITN, through production losses and expenditure, was estimated to be £1,121 per farm per year. The costs were estimated at £720, £860 and £2,133 for recovered, complicated and culled cases, respectively. Univariable and multivariable logistic regression models were used to explore the associations between the presence of ITN on farm and various risk factors. The presence of udder cleft dermatitis (UCD) (odds ratio 2.80; 95% CI: 1.54-5.07; p < 0.01) and chapped teats (odds ratio 6.07; 95% CI: 1.96-18.76; p < 0.01) in the milking herd was associated with the presence of ITN at the farm level. This is the first national questionnaire of ITN within GB and highlights the association of UCD and chapped teats with ITN at the farm level. While there are many limitations and potential bias around farmer questionnaires, these findings highlight several key areas for further disease investigation and possible intervention.