Summary The multifunctional-autoprocessing repeats-in-toxin (MARTXVv) toxin that harbours a varied repertoire of effector domains is the primary virulence factor of Vibrio vulnificus. Although ...ubiquitously present among Biotype I toxin variants, the 'Makes caterpillars floppy-like' effector domain (MCFVv) is previously unstudied. Using transient expression and protein delivery, MCFVv and MCFAh from the Aeromonas hydrophilaMARTXAh toxin are shown for the first time to induce cell rounding. Alanine mutagenesis across the C-terminal subdomain of MCFVv identified an Arg-Cys-Asp (RCD) tripeptide motif shown to comprise a cysteine protease catalytic site essential for autoprocessing of MCFVv. The autoprocessing could be recapitulated in vitro by the addition of host cell lysate to recombinant MCFVv, indicating induced autoprocessing by cellular factors. The RCD motif is also essential for cytopathicity, suggesting autoprocessing is essential first to activate the toxin and then to process a cellular target protein resulting in cell rounding. Sequence homology places MCFVv within the C58 cysteine protease family that includes the type III secretion effectors YopT from Yersinia spp. and AvrPphB from Pseudomonas syringae. However, the catalytic site RCD motif is unique compared with other C58 peptidases and is here proposed to represent a new subgroup of autopeptidase found within a number of putative large bacterial toxins.
BackgroundAmbulance services transport patients with infections and diseases and could pose a cross transmission risk to patients and staff through environmental contamination. The literature ...suggests that environmental pathogens are present on ambulances, cleaning is inconsistent and patient/staff impact is difficult to quantify. Eco-Mist developed a dry misting decontamination system for ambulance use called AmbuGard which works in <30 minutes and is 99.9999% effective against common pathogens. The research question is ‘What pathogens are present on North East Ambulance Service ambulances and what impact does adding the AmbuGard to the deep cleaning process make?’MethodsA two armed, randomised controlled trial enrolled fourteen ambulances during their regular 24 week deep clean which were 1:1 randomised to deep cleaning (control arm) or deep cleaning plus AmbuGard (intervention arm). Polywipe swabs were taken before and after cleaning from five locations selected for high rates of contact (steering wheel, shelf, side door grab rail, patient seat armrest, rear door handle/grab rail). Microbiology culture methods identified the presence and amount of bacterial organisms present including the selected pathogens: Enterococcus spp.; Enterobacter spp.; Klebsiella spp.; Staphylococcus aureus; Acinetobacter spp.; Pseudomonas spp.; Clostridium difficile; coagulase-negative staphylococci (CoNS)). The researcher taking the swabs and the laboratory were blinded to the trial arm.ResultsPathogens of interest were found on 10 (71%) vehicles. CoNS were found on all vehicles. Pathogens were found on all locations swabbed. Normal deep cleaning was effective at eliminating pathogens and the addition of AmbuGard showed no obvious improvement in effectiveness.ConclusionPathogens associated with healthcare acquired infections were found throughout all ambulances. Normal deep cleaning was effective and adding AmbuGard showed no obvious improvement. This was a small study at a single point in time. Further research is needed into temporal trends, how to reduce pathogens during normal clinical duties and patient/staff impact.
BackgroundSyndromic management remains the standard nongonococcal urethritis (NGU) treatment approach. Whether pathogen-specific signs/symptoms inform treatment decisions remains unclear. We ...identified men with single- and mixed-pathogen NGU and assessed for the presence of pathogen-specific signs or symptoms to improve syndromic management.MethodsAs part of an ongoing cohort study (the Idiopathic Urethritis Men’s Project IUMP), we recruited men with NGU. NGU was diagnosed by signs and/or symptoms of urethritis, and a urethral Gram stain with ≥5 neutrophils per high-power field without evidence of gram negative intracellular diplococci. Participants underwent a clinical history and physical exam, which documented specific self-reported symptoms and clinician observed signs. Single- and mixed-infections were identified by NAAT testing of first-catch urine for Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), Mycoplasma genitalium (MG), Trichomonas vaginalis (TV), and Ureaplasma urealyticum (UU); five-pathogen-negative cases were classified as idiopathic urethritis (IU).ResultsOne hundred fifty-five men with NGU are included in this analysis. The median age was 28 (range 18–63), 101 (65%) were African American, and 135 (87%) self-identified as heterosexual. The most commonly reported symptom was urethral discharge (92%), followed by burning/tingling (37%), and dysuria (28%). Over half of these men reported more than one symptom (58%). Single-pathogen NGU was detected in 99 (64%) men, mixed-pathogen in 14 (9%), and IU in 42 (27%). For single pathogen NGU, 53 (34%) had CT, 26 (17%) had MG, 3 (2%) had TV, and 17 (11%) had UU. We compared single-pathogen NGU, mixed-infection and IU for differences in signs or symptoms and found no pathogen-specific differences.ConclusionIn men with NGU, no pathogen-specific signs and symptoms were identified that could inform treatment decisions. Pathogen-specific point-of-care tests are needed.DisclosureNo significant relationships.
The Pine Wood Nematode (PWN)
Bursaphelenchus xylophilus
is the causal agent of the pine wilt disease, and a quarantine organism within the European Union. This pathogen was first detected in Portugal ...in 1999, associated to dead coastal pines (
Pinus pinaster
), its vector among trees being the native insect
Monochamus galloprovincialis
. Over the years, the management and control of both the nematode and the vector has been implemented by the Portuguese National Programme to Control the Pine Wood Nematode (PROLUNP), one of whose main current strategies is focused on the prevention of dispersal of wilt disease to new locations. This paper aims to explore how the pathogen and the forestry management strategy were perceived by the members of the parliament (MPs) of the Portuguese Republic, based on documents from 1999 until the present day.
IntroductionSexually Transmitted Infections (STIs) are increasing worldwide. Innovative approaches are required to eliminate barriers to STIs testing such as home-based self-sampling for patients ...that are difficult to reach or for whose that refuse to go for clinical collection. Aim of this study was to evaluate the performance of a new Home–based Self Vaginal FLOQSwabTM (HBSVF - COPAN Italia, Brescia) in combination with a commercially available real-time PCR assay, Anyplex II STI-7 (Seegene, Seoul, Korea) which detects seven major pathogens in a single reaction (Chlamydia trachomatis - CT, Neisseria gonorrhoeae - NG, Trichomonas vaginalis - TV, Mycoplasma hominis - MH, Mycoplasma genitalium - MG, Ureaplasma urealyticum - UU, and Ureaplasma parvum - UP). MethodsA total of 78 asymptomatic donors, employees of a private industry (aged 18 to 45 years) were voluntarily enrolled to STIs screening. The subjects answered to a standardise anonymized questionnaire regarding the easy of use of self vaginal collection. The new HBSV swab was collected in a domestic context by following the detailed “how to use it” instructions. After collection, the HBSV swabs were shipped at room temperature to the laboratory in Pievesestina and processed within five weeks. The threshold cycle value (Ct) of a human genomic target (internal control, IC) and Ct of pathogens (CT, NG, TV, MH, MG, UU, UP) were taken as parameters to assess respectively, the efficiency of self-sampling and presence of any inhibitor effects, the stability of nucleic acids on dry swabs. Resultsno failure results have been observed, the IC of all samples were amplified (average Ct 30). The real time PCR assay was able to identified 2/78 CT, 4/78 UU, 40/78 UP, 6/78 MH, 1/78 TV positive patients. No MG and NG positive patients have been detected. Women reported self-collection with HBSV easy and comfortable (100%).Conclusionthe new HBSV device showed excellent recovery and stability of nucleic acid of STI pathogens up to 5 weeks at room temperature. The HBSV is suitable for screening of STIs with real-time PCR assay.
Fungal plant pathogens are common in natural communities where they affect plant physiology, plant survival, and biomass production. Conversely, pathogen transmission and infection may be regulated ...by plant community characteristics such as plant species diversity and functional composition that favor pathogen diversity through increases in host diversity while simultaneously reducing pathogen infection via increased variability in host density and spatial heterogeneity. Therefore, a comprehensive understanding of multi-host-multi-pathogen interactions is of high significance in the context of biodiversity-ecosystem functioning. We investigated the relationship between plant diversity and aboveground obligate parasitic fungal pathogen ("pathogens" hereafter) diversity and infection in grasslands of a long-term, large-scale, biodiversity experiment with varying plant species (1-60 species) and plant functional group diversity (1-4 groups). To estimate pathogen infection of the plant communities, we visually assessed pathogen-group presence (i.e., rusts, powdery mildews, downy mildews, smuts, and leaf-spot diseases) and overall infection levels (combining incidence and severity of each pathogen group) in 82 experimental plots on all aboveground organs of all plant species per plot during four surveys in 2006.
Pathogen diversity, assessed as the cumulative number of pathogen groups on all plant species per plot, increased log-linearly with plant species diversity. However, pathogen incidence and severity, and hence overall infection, decreased with increasing plant species diversity. In addition, co-infection of plant individuals by two or more pathogen groups was less likely with increasing plant community diversity. We conclude that plant community diversity promotes pathogen-community diversity while at the same time reducing pathogen infection levels of plant individuals.
Our cover features an H&E staining of liver sections from Cryptococcus neoformans‐infected RAG‐1−/− mice after immune reconstitution with CD4+ T cells. Granulomatous inflammation is apparent with ...encapsulated cryptococcoci in the centre surrounded by immune cells, mainly donor T cells and myeloid cells of the recipient. The image is taken from Eschke et al. (pp. 3339–3350), where the authors present the first animal model of Cryptococcus neoformans‐related immune reconstitution inflammatory syndrome (IRIS), providing new insights into the pathogenesis.
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