scholarly journals Characterization and Molecular Epidemiology of a Fungal Infection of Edible Crabs (Cancer pagurus) and Interaction of the Fungus with the Dinoflagellate Parasite Hematodinium

2012 ◽  
Vol 79 (3) ◽  
pp. 783-793 ◽  
Author(s):  
Amanda L. Smith ◽  
Kristina M. Hamilton ◽  
Lucy Hirschle ◽  
Emma C. Wootton ◽  
Claire L. Vogan ◽  
...  
Keyword(s):  
Ribosomal Dna ◽  
Host Response ◽  
Small Subunit ◽  
Fungal Isolate ◽  
Content Type ◽  
Cancer Pagurus ◽  
South Wales ◽  
Disease Condition ◽  
Fungal Sepsis ◽  
Host Tissues

ABSTRACTThis study reports on an emerging fungal disease of the edible crab,Cancer pagurus. Juvenile (prerecruit) crabs were found to be subject to this disease condition during the months of May to September at two intertidal sites in South Wales, United Kingdom. Histopathology revealed that the fungi overwhelm the host response in the tissues, leading to progressive septicemia. The causative agent of this infection was isolated and grown in pure culture and was identified as a member of theOphiocordycepsclade by sequencing of the small subunit of the fungal ribosomal DNA (rDNA). Of the crabs naturally infected with the fungus, 94% had a coinfection with the parasitic dinoflagellateHematodiniumspecies. To determine if there was any interaction between the two disease-causing agents, apparently fungus-free crabs, both with and without naturalHematodiniuminfections, were challenged with the fungal isolate. The presence ofHematodiniumcaused a significant reduction in fungal multiplication in the hemocoel of the crabs in comparison to that inHematodinium-free individuals. Histopathology of coinfected crabs showed a systemic multiplication ofHematodiniumwithin host tissues, leading to a rapid death, whileHematodinium-free crabs experimentally infected with the fungal isolate died due to fungal sepsis (septicemia) with the same characteristic pathology as seen in natural infections.

scholarly journals New Degenerate Cytophaga-Flexibacter-Bacteroides-Specific 16S Ribosomal DNA-Targeted Oligonucleotide Probes Reveal High Bacterial Diversity in River Taff Epilithon

2002 ◽  
Vol 68 (1) ◽  
pp. 201-210 ◽  
Author(s):  
Louise A. O’Sullivan ◽  
Andrew J. Weightman ◽  
John C. Fry
Keyword(s):  
Bacterial Diversity ◽  
Ribosomal Dna ◽  
Phylogenetic Trees ◽  
Small Subunit ◽  
Target Range ◽  
Probe Design ◽  
Ribosomal Database Project ◽  
Bacterial Populations ◽  
16S Ribosomal Dna ◽  
South Wales

ABSTRACT River microbial communities play an important role in global nutrient cycles, and aggregated bacteria such as those in epilithic biofilms may be major contributors. In this study the bacterial diversity of River Taff epilithon in South Wales was investigated. A 16S ribosomal DNA (rDNA) clone library was constructed and analyzed by partial sequencing of 76 of 347 clones and hybridization with taxon-specific probes. The epilithon was found to be very diverse, with an estimated 59.6% of the bacterial populations not accounted for by these clones. Members of the Cytophaga-Flexibacter-Bacteroides division (CFBs) were most abundant in the library, representing 25% of clones, followed by members of the α subdivision of the division Proteobacteria (α-Proteobacteria), γ-Proteobacteria, gram-positive bacteria, Cyanobacteria, β-Proteobacteria, δ-Proteobacteria, and the Prosthecobacter group. This study concentrated on the epilithic CFB populations, and a new set of degenerate 16S rDNA probes was developed to enhance their detection, namely, CFB560, CFB562, and CFB376. The commonly used probe CF319a/b may frequently lead to the underestimation of CFB populations in environmental studies, because it does not fully detect members of the division. CFB560 had exact matches to 95.6% of CFBs listed in the Ribosomal Database Project (release 8.0) small-subunit phylogenetic trees, compared to 60% for CF319a/b. The CFB probes detected 66 of 347 epilithon TAF clones, and 60 of these were partially sequenced. They affiliated with the RDP-designated groups Cytophaga, Sphingobacterium, Lewinella, and Cytophaga aurantiaca. CFB560 and CF319a/b detected 94% (62 of 66) and 48.5% (32 of 66) of clones, respectively, and therefore CFB560 is recommended for future use. Probe design in this study illustrated that multiple degenerate positions can greatly increase target range without adversely effecting specificity or experimental performance.

scholarly journals Specificity of Associations between Bacteria and the Coral Pocillopora meandrina during Early Development

2012 ◽  
Vol 78 (20) ◽  
pp. 7467-7475 ◽  
Author(s):  
Amy Apprill ◽  
Heather Q. Marlow ◽  
Mark Q. Martindale ◽  
Michael S. Rappé
Keyword(s):  
Small Subunit ◽  
Rrna Genes ◽  
Polymorphism Analysis ◽  
Roseobacter Clade ◽  
Small Subunit Rrna ◽  
Content Type ◽  
Sterile Seawater ◽  
Show Evidence ◽  
Coral Health

ABSTRACTRelationships between corals and specific bacterial associates are thought to play an important role in coral health. In this study, the specificity of bacteria associating with the coralPocillopora meandrinawas investigated by exposing coral embryos to various strains of cultured marine bacteria, sterile seawater, or raw seawater and examining the identity, density, and location of incorporated cells. The isolates utilized in this experiment included members of the Roseobacter and SAR11 clades of theAlphaproteobacteria, aPseudoalteromonasspecies of theGammaproteobacteria, and aSynechococcusspecies of theCyanobacteriaphylum. Based on terminal restriction fragment length polymorphism analysis of small-subunit rRNA genes, similarities in bacterial communities associated with 170-h-old planulae were observed regardless of treatment, suggesting that bacteria may have been externally associated from the outset of the experiment. Microscopic examination ofP. meandrinaplanulae by fluorescencein situhybridization with bacterial and Roseobacter clade-specific oligonucleotide probes revealed differences in the densities and locations of planulae-associated cells. Planulae exposed to either raw seawater or strains ofPseudoalteromonasand Roseobacter harbored the highest densities of internally associated cells, of which 20 to 100% belonged to the Roseobacter clade. Planulae exposed to sterile seawater or strains of the SAR11 clade andSynechococcusdid not show evidence of prominent bacterial associations. Additional analysis of the raw-seawater-exposed planulae via electron microscopy confirmed the presence of internally associated prokaryotic cells, as well as virus-like particles. These results suggest that the availability of specific microorganisms may be an important factor in the establishment of coral-bacterial relationships.

scholarly journals Molecular Diversity of the Syndinean Genus Euduboscquella Based on Single-Cell PCR Analysis

2011 ◽  
Vol 78 (2) ◽  
pp. 334-345 ◽  
Author(s):  
Tsvetan R. Bachvaroff ◽  
Sunju Kim ◽  
Laure Guillou ◽  
Charles F. Delwiche ◽  
D. Wayne Coats
Keyword(s):  
Large Subunit ◽  
Small Subunit ◽  
Base Change ◽  
Pcr Analysis ◽  
Ssu Rrna ◽  
Compensatory Base Change ◽  
Content Type ◽  
Single Cell Pcr ◽  
Group I ◽  
Lsu Rrna

ABSTRACTThe genusEuduboscquellais one of a few described genera within the syndinean dinoflagellates, an enigmatic lineage with abundant diversity in marine environmental clone libraries based on small subunit (SSU) rRNA. The region composed of the SSU through to the partial large subunit (LSU) rRNA was determined from 40 individual tintinnid ciliate loricae infected withEuduboscquellasampled from eight surface water sites in the Northern Hemisphere, producing seven distinct SSU sequences. The corresponding host SSU rRNA region was also amplified from eight host species. The SSU tree ofEuduboscquellaand syndinean group I sequences from environmental clones had seven well-supported clades and one poorly supported clade across data sets from 57 to 692 total sequences. The genusEuduboscquellaconsistently formed a supported monophyletic clade within a single subclade of group I sequences. For most parasites with identical SSU sequences, the more variable internal transcribed spacer (ITS) to LSU rRNA regions were polymorphic at 3 to 10 sites. However, inE. cachonithere was variation between ITS to LSU copies at up to 20 sites within an individual, while in a parasite ofTintinnopsisspp., variation between different individuals ranged up to 19 polymorphic sites. However, applying the compensatory base change model to the ITS2 sequences suggested no compensatory changes within or between individuals with the same SSU sequence, while one to four compensatory changes between individuals with similar but not identical SSU sequences were found. Comparisons between host and parasite phylogenies do not suggest a simple pattern of host or parasite specificity.

Systematic status of Campydora Cobb, 1920 (Nematoda: Campydorina)

Nematology ◽  
2003 ◽  
Vol 5 (5) ◽  
pp. 699-711 ◽  
Author(s):  
Peter Mullin ◽  
Timothy Harris ◽  
Thomas Powers
Keyword(s):  
Maximum Likelihood ◽  
Ribosomal Dna ◽  
Dna Sequences ◽  
Maximum Parsimony ◽  
Phylogenetic Analyses ◽  
Small Subunit ◽  
Systematic Position ◽  
Nominal Species ◽  
Competing Hypotheses ◽  
Small Subunit Ribosomal Dna

AbstractThe systematic position of Campydora Cobb, 1920, which possesses many unique morphological features, especially in pharyngeal structure and stomatal armature, has long been a matter of uncertainty with the 'position of the Campydorinae' (containing only Campydora) being questionable. A review of the morphology of C. demonstrans, the only nominal species of Campydora concluded that the species warranted placement as the sole member of a monotypic suborder, Campydorina, in the order Dorylaimida. Others placed Campydorina in the order Enoplida. We conducted phylogenetic analyses, using 18s small subunit ribosomal DNA sequences generated from a number of taxa in the subclasses Enoplia and Dorylaimia, to evaluate these competing hypotheses. Although precise taxonomic placement of the genus Campydora and the identity of its closest living relatives is in need of further investigation, our analyses, under maximum parsimony, distance, and maximum likelihood criteria, unambiguously indicate that Campydora shares a common, more recent, ancestry with genera such as Alaimus, Pontonema, Tripyla and Ironus (Enoplida), rather than with any members of Dorylaimida, Mononchida or Triplonchida.

Commentary on the harm reduction reference group of justice health and forensic mental health network and corrective services NSW, Australia

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Julia Anne Silano ◽  
Carla Treloar ◽  
Thomas Wright ◽  
Tracey Brown ◽  
Colette McGrath ◽  
...  
Keyword(s):  
Public Health ◽  
Mental Health ◽  
Health Care ◽  
Harm Reduction ◽  
Reference Group ◽  
New South ◽  
Forensic Mental Health ◽  
Content Type ◽  
Health Network ◽  
South Wales

Purpose This commentary aims to reveal how a steering committee has effectively responded to advancing accessibility to harm reduction resources, hepatitis C virus (HCV) policy and health strategies within adult prison settings in New South Wales (NSW). Design/methodology/approach By reviewing the audit approach taken by the of the Justice Health and Forensic Mental Health Network and Corrective Services New South Wales Harm Reduction Reference Group (JHFMHN/CSNSW HRRG), this commentary emphasizes the committee’s success in identifying contemporary harm reduction issues that affect people in custodial settings. This commentary is a compilation of data gathered through the 2018 JHFMHN/CSNSW HRRG audit and corresponding program materials. Conclusions regarding the effectiveness of the working group’s audit were drawn by critically appraising the JHFMHN/CSNSW HRRG’s Final Audit Report (JHFMHN and CSNSW, 2018) with reference to current harm reduction literature. Findings The HRRG has provided leadership, professional representation and strategic advice on the development, implementation, monitoring and evaluation of best practice harm reduction strategies in prison settings. The HRRG developed and maintained networks and information exchange between the state-wide HCV health network, corrections services and the NSW harm reduction sector at large. Public health partnerships and advocacy that involve all key players, such as the HRRG, will continue to be crucial to remove barriers to enhancing HCV harm reduction measures especially in NSW prison settings. Social implications Strategies such as primary prevention and treatment can mitigate the spread of HCV in the custodial system. This audit of access to harm reduction resources was conducted on behalf of the diverse group of professionals, scholars and stakeholders comprising the HRRG. This audit and other advocacy efforts of this committee can facilitate future access to quality healthcare and the necessary policies required to support a healthier prison population at large. Originality/value Collaborating with health authorities, researchers and social service workers can enable prison health-care systems to be guided by wider health workforce programs and public health standards. This collaboration can reduce the professional isolation of custodial health-care staff and promote a balanced approach to harm reduction policies by ensuring an equitable focus on both health and security imperatives.

scholarly journals Hyperbaric Oxygen Sensitizes Anoxic Pseudomonas aeruginosa Biofilm to Ciprofloxacin

2017 ◽  
Vol 61 (11) ◽  
Author(s):  
Mette Kolpen ◽  
Christian J. Lerche ◽  
Kasper N. Kragh ◽  
Thomas Sams ◽  
Klaus Koren ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Hyperbaric Oxygen ◽  
Bactericidal Activity ◽  
Host Response ◽  
Polymorphonuclear Leukocytes ◽  
Bactericidal Effect ◽  
Aerobic Respiration ◽  
Hyperbaric Oxygen Treatment ◽  
Content Type ◽  
Oxygen Treatment

ABSTRACT Chronic Pseudomonas aeruginosa lung infection is characterized by the presence of endobronchial antibiotic-tolerant biofilm, which is subject to strong oxygen (O2) depletion due to the activity of surrounding polymorphonuclear leukocytes. The exact mechanisms affecting the antibiotic susceptibility of biofilms remain unclear, but accumulating evidence suggests that the efficacy of several bactericidal antibiotics is enhanced by stimulation of aerobic respiration of pathogens, while lack of O2 increases their tolerance. In fact, the bactericidal effect of several antibiotics depends on active aerobic metabolism activity and the endogenous formation of reactive O2 radicals (ROS). In this study, we aimed to apply hyperbaric oxygen treatment (HBOT) to sensitize anoxic P. aeruginosa agarose biofilms established to mimic situations with intense O2 consumption by the host response in the cystic fibrosis (CF) lung. Application of HBOT resulted in enhanced bactericidal activity of ciprofloxacin at clinically relevant durations and was accompanied by indications of restored aerobic respiration, involvement of endogenous lethal oxidative stress, and increased bacterial growth. The findings highlight that oxygenation by HBOT improves the bactericidal activity of ciprofloxacin on P. aeruginosa biofilm and suggest that bacterial biofilms are sensitized to antibiotics by supplying hyperbaric O2.

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