221 results on '"Downes, J."'
Search Results
2. Derived Polymorphic Amplified Cleaved Sequence (dPACS) Assay.
- Author
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Kaundun SS, Hutchings SJ, Downes J, and Baker K
- Subjects
- Polymorphism, Restriction Fragment Length, Mutation, Polymerase Chain Reaction methods, Codon, Photosystem II Protein Complex genetics
- Abstract
The derived polymorphic amplified cleaved sequence (dPACS) assay is a simple polymerase chain reaction/restriction fragment length polymorphism (PCR-RFLP)-based procedure for detecting known single-nucleotide polymorphisms (SNPs) and deletion-insertion polymorphisms (DIPs). It is relatively straightforward to carry out using basic and commonly available molecular biology kits. The method differs from other PCR-RFLP assays in that it employs 35-55 bp primer pairs that encompass the entire targeted DNA region except for a few diagnostic nucleotides being examined. In so doing, it allows for the introduction of nucleotide mismatches in one or both primers for differentiating wild from mutant sequences following polymerase chain reaction, restriction digestion and MetaPhor gel electrophoresis. Primer design and the selection of discriminating enzymes are achieved with the help of the dPACS 1.0 program. The method is exemplified here with the positive detection of serine 264-psbA, a key determinant for the effective binding of some photosystem II inhibitors to their target. A serine-to-glycine mutation at codon 264 of psbA causes resistance to serine-binding photosystem II herbicides in several grasses and broad-leaf weeds, including Amaranthus retroflexus, which is employed in this study., (© 2023. The Author(s), under exclusive license to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2023
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3. Prevalence of epitheliocystis in freshwater Atlantic salmon reared in flow-through and recirculation aquaculture systems.
- Author
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Quezada-Rodriguez PR, Taylor RS, Downes J, Egan F, White S, Brenan A, Rigby M, Nowak BF, Ruane NM, and Wynne JW
- Subjects
- Animals, Aquaculture, Fresh Water, Gills pathology, Prevalence, Bacterial Infections veterinary, Fish Diseases microbiology, Salmo salar
- Abstract
Epitheliocystis, an intracellular bacterial infection in the gills and skin epithelium, has been frequently reported in Atlantic salmon (Salmo salar) during freshwater production in a number of countries. This study describes the prevalence and intensity of a natural epitheliocystis infection present in the gills of two strains of Atlantic salmon reared in either a flow-through (FT) or a recirculation aquaculture system (RAS) in Ireland. Repeated sampling of gills prior to and throughout seawater transfer, histology and quantitative real-time PCR were used to determine infection prevalence and intensity. Despite no clinical gill disease, and minor histopathological changes, epitheliocystis lesions were identified in histology at all time points. Specific PCR confirmed the presence of Candidatus Clavichlamydia salmonicola in both strains and its number of copies was correlated with intensity of epitheliocystis lesions. A significant interaction between hatchery system and fish strain on the prevalence and intensity of gill epitheliocystis was found both using histological and molecular methods. Specifically, fish from FT had higher prevalence and intensity than RAS reared fish and within FT, the Irish cohort were more affected than Icelandic., (© 2022 CSIRO. Journal of Fish Diseases published by John Wiley & Sons Ltd.)
- Published
- 2022
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4. Two Wrongs Do Not Always Make a Right.
- Author
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Perez-Downes J, Kusumoto F, and Goldschlager N
- Subjects
- Aged, Coronary Angiography methods, Coronary Vessels diagnostic imaging, Graft Occlusion, Vascular surgery, Humans, Reoperation, ST Elevation Myocardial Infarction surgery, Coronary Vessels surgery, Electrocardiography methods, Graft Occlusion, Vascular diagnosis, ST Elevation Myocardial Infarction diagnosis, Stents
- Published
- 2021
- Full Text
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5. Impact of a Novel W2027L Mutation and Non-Target Site Resistance on Acetyl-CoA Carboxylase-Inhibiting Herbicides in a French Lolium multiflorum Population.
- Author
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Kaundun SS, Downes J, Jackson LV, Hutchings SJ, and Mcindoe E
- Subjects
- Acetyl-CoA Carboxylase antagonists & inhibitors, Acetyl-CoA Carboxylase chemistry, Acetyl-CoA Carboxylase metabolism, Binding Sites, Enzyme Inhibitors toxicity, Herbicides toxicity, Lolium drug effects, Protein Binding, Acetyl-CoA Carboxylase genetics, Herbicide Resistance, Lolium genetics, Mutation, Missense
- Abstract
Herbicides that inhibit acetyl-CoA carboxylase (ACCase) are among the few remaining options for the post-emergence control of Lolium species in small grain cereal crops. Here, we determined the mechanism of resistance to ACCase herbicides in a Lolium multiflorum population (HGR) from France. A combined biological and molecular approach detected a novel W2027L ACCase mutation that affects aryloxyphenoxypropionate (FOP) but not cyclohexanedione (DIM) or phenylpyraxoline (DEN) subclasses of ACCase herbicides. Both the wild-type tryptophan and mutant leucine 2027-ACCase alleles could be positively detected in a single DNA-based-derived polymorphic amplified cleaved sequence (dPACS) assay that contained the targeted PCR product and a cocktail of two discriminating restriction enzymes. Additionally, we identified three well-characterised I1781L, I2041T, and D2078G ACCase target site resistance mutations as well as non-target site resistance in HGR. The non-target site component endowed high levels of resistance to FOP herbicides whilst partially impacting on the efficacy of pinoxaden and cycloxydim. This study adequately assessed the contribution of the W2027L mutation and non-target site mechanism in conferring resistance to ACCase herbicides in HGR. It also highlights the versatility and robustness of the dPACS method to simultaneously identify different resistance-causing alleles at a single ACCase codon.
- Published
- 2021
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6. Employing OVs from outside the UK.
- Author
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Downes J and Loeb J
- Subjects
- Animals, United Kingdom, Veterinary Medicine
- Published
- 2021
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7. Impact of ECG Characteristics on the Performance of an Artificial Intelligence Enabled ECG for Predicting Left Ventricular Dysfunction.
- Author
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Perez-Downes J, Fitzgerald P, Adedinsewo D, Carter RE, Noseworthy PA, and Kusumoto F
- Subjects
- Aged, Emergency Service, Hospital, Female, Humans, Male, Middle Aged, Predictive Value of Tests, Prognosis, Reproducibility of Results, Retrospective Studies, Ventricular Dysfunction, Left physiopathology, Artificial Intelligence, Electrocardiography, Heart Rate, Signal Processing, Computer-Assisted, Ventricular Dysfunction, Left diagnosis, Ventricular Function, Left
- Published
- 2021
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8. To Sample or Not to Sample? An Analysis of the Need for Salmonella Sampling of Smaller Poultry Processors.
- Author
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Hill A, Muñoz V, Downes J, Schuppers M, Buncic S, O'Brien S, and Stärk KDC
- Subjects
- Animals, European Union, Food Microbiology, Uncertainty, United Kingdom, Food Handling, Poultry microbiology, Salmonella isolation & purification
- Abstract
Within the European Union (EU), microbiological criteria (MC) sampling for Salmonella in poultry was introduced in 2005. In particular, processors had to meet a target of fewer than seven positive samples out of 50. However, processors producing small amounts of poultry meat did not have to sample if national authorities determined this was an acceptable risk. The U.K. Food Standards Agency (FSA) thus has a sampling regime based on throughput that allows smaller processors not to sample. In 2011, the limit of 7/50 was reduced to 5/50. Given the current uncertainty regarding U.K. trade relations with the EU, the U.K. FSA decided to conduct a new risk assessment of the risks of Salmonella produced by smaller processors, to determine whether sampling was now necessary. Current evidence suggests that an MC sampling regime in smaller slaughterhouses is not warranted from a national public health perspective. Because of the insensitivities of the MC sampling scheme, the introduction of MC sampling into smaller slaughterhouses would only be necessary if the suspected carcass prevalence was 15% or more. While our analysis is prone to uncertainty, we estimated that the carcass prevalence in smaller processors is below this. Thus, we recommended that the current sampling framework, allowing smaller processors not to sample, was still applicable., (© 2020 Society for Risk Analysis.)
- Published
- 2020
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9. Genetic diversity among geographically distant isolates of Neoparamoeba perurans.
- Author
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Hansen H, Botwright NA, Cook MT, Douglas A, Downes J, Gallagher MD, Ruane NM, and Matejusova I
- Subjects
- Amebiasis, Animals, Fish Diseases, Gills, Salmo salar, Genetic Variation
- Abstract
The present study explored the use of 2 common genetic markers, the mitochondrial cytochrome oxidase I (COI) and the ribosomal internal transcribed spacer (ITS) to infer the relationship between geographically distant isolates of the protozoan gill parasite Neoparamoeba perurans, the agent responsible for amoebic gill disease in farmed Atlantic salmon worldwide. Present data confirmed that the ITS marker is suitable for Neoparamoeba species discrimination; however, it is not recommended as a population marker due to the presence of multiple copies of ITS within both N. perurans clonal and polycultures. On the other hand, in the partial COI gene analysed here, a low variability was observed, with 8 haplotypes recovered from N. perurans samples collected from Europe (Ireland, Norway, Scotland) and Tasmania (Australia). In Europe, the COI haplotypes which have more recently been detected in aquaculture are different to the haplotypes associated with the original gill disease emergence in Ireland in 1997 and Norway in 2006. The presence of unique COI haplotypes in different continents suggests the presence of multiple distinct reservoirs of the pathogen in both Europe and Tasmania. Isolates from additional geographical locations are required to fully understand the origins and routes for the spread of N. perurans worldwide.
- Published
- 2019
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10. First Quantification of the Controlling Role of Humic Substances in the Transport of Iron Across the Surface of the Arctic Ocean.
- Author
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Laglera LM, Sukekava C, Slagter HA, Downes J, Aparicio-Gonzalez A, and Gerringa LJA
- Subjects
- Arctic Regions, Oceans and Seas, Solubility, Humic Substances, Iron
- Abstract
One of the main reasons behind our current lack of understanding of iron cycling in the oceans is our inability to characterize the ligands that control iron solubility, photosensitivity, reactivity, and bioavailability. We currently lack consensus about the nature and origin of these ligands. Here, we present the first field application of a new methodological development that allows the selective quantification of the fraction of Fe complexed to humic substances (HS). In the HS-rich surface Arctic waters, including the Fe-rich Transpolar Drift (TPD), we found that HS iron binding groups were largely occupied by iron (49%). The overall contribution of Fe-HS complexes to DFe concentrations was substantial at 80% without significant differences between TPD and non-TPD waters. Stabilization and transport of large concentrations of DFe across the surface of the Arctic Ocean are due to the formation of high concentrations of Fe-HS complexes. Competition of Arctic Fe-HS complexes with desferrioxamine and EDTA indicated that their stability constants are considerably higher than the stability constants previously found for riverine HS in temperate estuaries and HS standard material. This is the first case of identification of the ligand-dominating iron speciation over a specific region of the global ocean.
- Published
- 2019
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11. Changes in distribution, morphology and ultrastructure of chloride cell in Atlantic salmon during an AGD infection.
- Author
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Chang YC, Hamlin-Wright H, Monaghan S, Herath T, Baily J, Del Pozo J, Downes J, Preston A, Chalmers L, Jayasuriya N, Bron JE, Adams A, and Fridman S
- Subjects
- Amebiasis pathology, Animals, Epithelium microbiology, Epithelium pathology, Epithelium ultrastructure, Gene Expression physiology, Gills cytology, Gills microbiology, Gills ultrastructure, Immunohistochemistry veterinary, Microscopy, Electron, Transmission veterinary, Amebiasis veterinary, Fish Diseases pathology, Gills pathology, Salmo salar
- Abstract
Amoebic gill disease (AGD) is emerging as one of the most significant health challenges affecting farmed Atlantic salmon in the marine environment. It is caused by the amphizoic amoeba Neoparamoeba perurans, with infestation of gills causing severe hyperplastic lesions, compromising overall gill integrity and function. This study used histology, transmission electron microscopy (TEM), immunohistochemistry and transcript expression to relate AGD-associated pathological changes to changes in the morphology and distribution of chloride cells (CCs) in the gills of Atlantic salmon (Salmo salar L.) showing the progression of an AGD infection. A marked reduction in numbers of immunolabelled CCs was detected, and a changing pattern in distribution and morphology was closely linked with the level of basal epithelial hyperplasia in the gill. In addition, acute degenerative ultrastructural changes to CCs at the lesion site were observed with TEM. These findings were supported by the early-onset downregulation of Na
+ /K+ -ATPase transcript expression. This study provides supportive evidence that histological AGD lesion assessment was a good qualitative tool for AGD scoring and corresponded well with qPCR genomic Paramoeba perurans quantification. Ultrastructural changes induced in salmon CCs as a result of AGD are reported here for the first time., (© 2019 John Wiley & Sons Ltd.)- Published
- 2019
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12. Towards a narrative cardiology: exploring, holding and re-presenting narratives of heart disease.
- Author
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Biglino G, Bucciarelli-Ducci C, Caputo M, Carel H, Hurwitz B, Layton S, Stretton-Downes J, Tiwari N, Wray J, and Vaccarella M
- Abstract
Competing Interests: Conflicts of Interest: The authors have no conflicts of interest to declare.
- Published
- 2019
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13. Photochemical Etching of Carbonyl Groups from a Carbon Matrix: The (001) Diamond Surface.
- Author
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Weston L, Downes JE, Baldwin CG, Granados E, Tawfik SA, Cui XY, Stampfl C, and Mildren RP
- Abstract
The surface of diamond is reported to undergo nonablative photochemical etching when exposed to ultraviolet (UV) radiation which allows controlled single and partial layer removal of lattice layers. Oxygen termination of surface dangling bonds is known to be crucial for the etching process; however, the exact mechanism of carbon ejection remains unclear. We investigate the interaction of UV laser pulses with oxygen-terminated diamond surfaces using atomic-scale surface characterization combined with first-principles time-dependent density functional theory calculations. We present evidence for laser-induced desorption (LID) from carbonyl functional groups at the diamond {001} surface. The doubly bonded carbonyl group is photoexcited into a triply bonded CO-like state, including scission of the underlying C─C bonds. The carbon removal process in LID is atom by atom; therefore, this mechanism provides a novel "top-down" approach for creating nanostructures on the surface of diamond and other carbon-containing semiconductors.
- Published
- 2019
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14. Dynamic right ventricular outflow tract obstruction from a pedunculated cardiac metastasis.
- Author
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Maharaj S, Chang S, Seegobin K, Perez-Downes J, Zuberi L, and Shaikh M
- Subjects
- Carcinoma, Squamous Cell complications, Carcinoma, Squamous Cell secondary, Echocardiography, Fatal Outcome, Female, Heart Neoplasms complications, Heart Neoplasms secondary, Humans, Middle Aged, Positron-Emission Tomography, Carcinoma, Squamous Cell diagnostic imaging, Heart Neoplasms diagnostic imaging, Urinary Bladder Neoplasms pathology, Ventricular Outflow Obstruction etiology
- Published
- 2018
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15. Determination of the contribution of humic substances to iron complexation in seawater by catalytic cathodic stripping voltammetry.
- Author
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Sukekava C, Downes J, Slagter HA, Gerringa LJA, and Laglera LM
- Abstract
Improving our understanding of iron cycling in ocean waters is one of the most challenging tasks in oceanographic studies and requires new analytical strategies. The low solubility of inorganic iron in oxygen saturated waters is increased by organic complexation with a variety of natural ligands, the nature of which is a topic of debate. Electrochemical methods are important for speciation studies since they allow direct measurement of iron complexes at limits of detection below iron concentrations in ocean waters. Most of the natural iron ligands do not form electrolabile iron complexes with working electrodes currently in use. Humic substances are the exception as their iron complexes can be detected by cathodic voltammetry if a strong oxidant such as bromate is added for a catalytic reoxidation of iron. Here we propose a rearrangement and extension of the original analytical protocol (Laglera et al., 2007) [1]. Firstly, the humic standard prepared in ultrapure water is carefully saturated with iron before use, preventing underestimation of the iron-humic complexes during calibration. Secondly, before starting the common voltammetric analysis under iron saturation, extra voltammograms are collected at the natural iron concentration. We demonstrate that this rearrangement permits the determination of the percentage of iron-binding groups of humic substances in the sample that were originally bound to iron. After calibration, the concentration of iron present in the sample as humic complexes can be quantified. This is the first analytical development leading to the quantification of the contribution of a determined type of natural ligands to the organic speciation of iron in seawater. As a proof of concept we measured the concentration of Fe-HS complexes in Arctic Ocean waters characterized by a high content in terrigenous organic matter. We corroborated the importance of humic substances in the lateral transport of high concentrations of iron from the Arctic Ocean into the North Atlantic Ocean., (Copyright © 2018 Elsevier B.V. All rights reserved.)
- Published
- 2018
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16. Legionnaires' Disease Outbreak on a Merchant Vessel, Indian Ocean, Australia, 2015.
- Author
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Inglis TJJ, Spittle C, Carmichael H, Downes J, Chiari M, McQueen-Mason A, Merritt AJ, Hodge M, Murray RJ, and Dowse GK
- Subjects
- Australia epidemiology, History, 21st Century, Humans, Indian Ocean, Legionnaires' Disease history, Legionnaires' Disease microbiology, Legionnaires' Disease transmission, Middle Aged, Seasons, Disease Outbreaks, Legionellosis genetics, Legionnaires' Disease epidemiology, Ships, Travel-Related Illness
- Abstract
Two cases of Legionnaires' disease and 1 of Pontiac fever occurred among the crew of a merchant ship operating off the shores of Australia. PCR assays identified potential sources in the ship's cabins. Modification of maritime regulations for Legionnaires' disease prevention in commercial vessels is needed for nonpassenger merchant ships.
- Published
- 2018
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17. Prognostic utility of NT-proBNP greater than 70,000 pg/mL in patients with end stage renal disease.
- Author
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Perez-Downes J, Palacio C, Ibrahim S, Shelley P, Miller A, and Reddy P
- Published
- 2018
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18. Investigation of co-infections with pathogens associated with gill disease in Atlantic salmon during an amoebic gill disease outbreak.
- Author
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Downes JK, Yatabe T, Marcos-Lopez M, Rodger HD, MacCarthy E, O'Connor I, Collins E, and Ruane NM
- Abstract
Gill diseases are a complex and multifactorial challenge for marine farmed Atlantic salmon. Co-infections with putative pathogens are common on farms; however, there is a lack of knowledge in relation to the potential effect co-infections may have on pathology. The objective of this study was to determine the prevalence and potential effects of Neoparamoeba perurans, Desmozoon lepeophtherii, Candidatus Branchiomonas cysticola, Tenacibaculum maritimum and salmon gill poxvirus (SGPV) during a longitudinal study on a marine Atlantic salmon farm. Real-time PCR was used to determine the presence and sequential infection patterns of these pathogens on gill samples collected from stocking until harvest. A number of multilevel models were used to determine the effect of these putative pathogens on gill health (measured as gill histopathology score), while adjusting for the effect of water temperature and time since the last freshwater treatment. Results indicate that between 12 and 16 weeks post-seawater transfer (wpst), colonization of the gills by all pathogens had commenced and by week 16 of marine production each of the pathogens had been detected. D. lepeophtherii and Candidatus B. cysticola were by far the most prevalent of the potential pathogens detected during this study. Detections of T. maritimum were found to be significantly correlated with temperature showing distinct seasonality. Salmon gill poxvirus was found to be highly sporadic and detected in the first sampling point, suggesting a carryover from the freshwater stage of production. Finally, the model results indicated no clear effect between any of the pathogens. Additionally, the models showed that the only variable which had a consistent effect on the histology score was N. perurans., (© 2018 John Wiley & Sons Ltd.)
- Published
- 2018
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19. Consideration of atrial arrhythmias associated with cardiac tamponade and pericarditis.
- Author
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Maharaj S, Perez-Downes J, Seegobin K, and Chang S
- Subjects
- Adult, Female, Humans, Lupus Erythematosus, Systemic complications, Male, Atrial Fibrillation etiology, Cardiac Tamponade complications, Pericarditis complications
- Published
- 2018
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20. Severe carvedilol toxicity without overdose - caution in cirrhosis.
- Author
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Maharaj S, Seegobin K, Perez-Downes J, Bajric B, Chang S, and Reddy P
- Abstract
Background: Carvedilol is used in the management of hypertension, ischemic heart disease, heart failure and most recently, portal hypertension. It has been associated with improved outcomes regarding variceal bleeding, hepatic decompensation and death when compared to propranolol and endoscopic band ligation. The main cause of portal hypertension is cirrhosis and therefore carvedilol is increasingly used in these patients. Due to its extensive hepatic metabolism, carvedilol is contraindicated in severe hepatic impairment. However, there are no dosage adjustments in the manufacturer's labelling for mild to moderate hepatic impairment., Case Presentation: We present a case of cardiogenic shock that occurred after carvedilol 25 mg orally was administered to a patient with cirrhosis. As there was no overdose, the diagnosis was based on clinical recognition of the toxidrome. The patient was successfully treated with glucagon 5 mg bolus followed by infusion., Conclusions: Patients with cirrhosis represent a special at-risk group for beta blocker toxicity. The typical threshold for carvedilol toxicity in overdose is 50 mg but in patients with cirrhosis this is not applicable. Nurses and physicians need to recognize the toxidrome early. Hospitals where carvedilol is used in patients with cirrhosis should have glucagon in formulary at doses to treat toxicity (bolus and infusion). Finally, dose adjustment and slow uptitration of carvedilol in cirrhosis is recommended.
- Published
- 2017
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21. The Role of Controlled Surface Topography and Chemistry on Mouse Embryonic Stem Cell Attachment, Growth and Self-Renewal.
- Author
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Macgregor M, Williams R, Downes J, Bachhuka A, and Vasilev K
- Abstract
The success of stem cell therapies relies heavily on our ability to control their fate in vitro during expansion to ensure an appropriate supply. The biophysical properties of the cell culture environment have been recognised as a potent stimuli influencing cellular behaviour. In this work we used advanced plasma-based techniques to generate model culture substrates with controlled nanotopographical features of 16 nm, 38 nm and 68 nm in magnitude, and three differently tailored surface chemical functionalities. The effect of these two surface properties on the adhesion, spreading, and self-renewal of mouse embryonic stem cells (mESCs) were assessed. The results demonstrated that physical and chemical cues influenced the behaviour of these stem cells in in vitro culture in different ways. The size of the nanotopographical features impacted on the cell adhesion, spreading and proliferation, while the chemistry influenced the cell self-renewal and differentiation., Competing Interests: The authors declare no conflict of interest.
- Published
- 2017
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22. Atypical presentation of a ventricular papillary fibroelastoma.
- Author
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Perez-Downes J, Dietzius H, Ibrahim S, Jayasankar V, and Oberst L
- Published
- 2017
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23. Detection of Clostridium perfringens toxin genes in the gut microbiota of autistic children.
- Author
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Finegold SM, Summanen PH, Downes J, Corbett K, and Komoriya T
- Subjects
- Bacteriological Techniques, Child, Child, Preschool, Clostridium perfringens isolation & purification, Feces microbiology, Female, Humans, Male, Polymerase Chain Reaction, Autistic Disorder microbiology, Bacterial Toxins genetics, Clostridium perfringens genetics, Gastrointestinal Tract microbiology
- Abstract
We studied stool specimens from 33 autistic children aged 2-9 years with gastrointestinal (GI) abnormalities and 13 control children without autism and without GI symptoms. We performed quantitative comparison of all Clostridium species and Clostridium perfringens strains from the fecal microbiota by conventional, selective anaerobic culture methods. We isolated C. perfringens strains and performed PCR analysis for the main C. perfringens toxin genes, alpha, beta, beta2, epsilon, iota and C. perfringens enterotoxin gene. Our results indicate that autistic subjects with gastrointestinal disease harbor statistically significantly (p = 0.031) higher counts of C. perfringens in their gut compared to control children. Autistic subjects also harbor statistically significantly (p = 0.015) higher counts of beta2-toxin gene-producing C. perfringens in their gut compared to control children, and the incidence of beta2-toxin gene-producing C. perfringens is significantly higher in autistic subjects compared to control children (p = 0.014). Alpha toxin gene was detected in all C. perfringens strains studied. C. perfringens enterotoxin gene was detected from three autistic and one control subject. Beta, epsilon, and iota toxin genes were not detected from autistic or control subjects., (Copyright © 2017 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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24. On-chip generation of heralded photon-number states.
- Author
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Vergyris P, Meany T, Lunghi T, Sauder G, Downes J, Steel MJ, Withford MJ, Alibart O, and Tanzilli S
- Abstract
Beyond the use of genuine monolithic integrated optical platforms, we report here a hybrid strategy enabling on-chip generation of configurable heralded two-photon states. More specifically, we combine two different fabrication techniques, i.e., non-linear waveguides on lithium niobate for efficient photon-pair generation and femtosecond-laser-direct-written waveguides on glass for photon manipulation. Through real-time device manipulation capabilities, a variety of path-coded heralded two-photon states can be produced, ranging from product to entangled states. Those states are engineered with high levels of purity, assessed by fidelities of 99.5 ± 8% and 95.0 ± 8%, respectively, obtained via quantum interferometric measurements. Our strategy therefore stands as a milestone for further exploiting entanglement-based protocols, relying on engineered quantum states, and enabled by scalable and compatible photonic circuits.
- Published
- 2016
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25. A Curious Case of Proximal Muscle Weakness with Eosinophilic Polymyositis.
- Author
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Harris C, Ali R, Perez-Downes J, Baidoun F, DeLima M, Shah J, Aung W, and Makary RF
- Abstract
Eosinophilic polymyositis (EPM) is part of a rare disorder, eosinophilic myopathies (EM), which is a form of polymyositis characterized by the presence of eosinophils in muscle biopsy sections and occasionally blood eosinophilia. Herein, we are presenting an interesting case of eosinophilic polymyositis presenting with muscle pain with no other organ systems involved.
- Published
- 2016
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26. Challenges in Treating Secondary Syphilis Osteitis in an Immunocompromised Patient with a Penicillin Allergy: Case Report and Review of the Literature.
- Author
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Ali R, Perez-Downes J, Baidoun F, Al Turk B, Isache C, Mohan G, and Perniciaro C
- Abstract
Syphilis is a sexually transmitted infection that remains fairly commonplace. The introduction of penicillin aided in curbing the incidence of disease; however, with the advent of the human immunodeficiency virus (HIV), syphilis is now on a resurgence with sometimes curious presentations. We present a case of a 36-year-old Caucasian gentleman with untreated HIV who complained of a skin eruption and joint pains for 6 weeks, prompting the diagnosis of secondary syphilis osteitis. Skin lesions were reminiscent of "malignant" syphilis. CD4 count was 57 cells/μL. RPR was elevated with 1 : 64 titer and positive confirmatory TP-PA. Radiography of the limbs revealed polyostotic cortical irregularities corroborated on bone scintigraphy. The patient had an unknown penicillin allergy and was unwilling to conduct a trial of penicillin-based therapy. He was subsequently treated with doxycycline 100 mg twice daily for 6 weeks and commenced antiretroviral therapy, noting dramatic improvement in both the skin lesions and joint pains. Unfortunately, he defaulted on follow-up, precluding serial RPR and bone imaging. Penicillin allergies have proven to be quite a conundrum in such patients, without much recourse for alternative therapy. Doxycycline with/without azithromycin is other options worth considering.
- Published
- 2016
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27. Amphetamine Containing Dietary Supplements and Acute Myocardial Infarction.
- Author
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Perez-Downes J, Hritani A, Baldeo C, and Antoun P
- Abstract
Weight loss is one of the most researched and marketed topics in American society. Dietary regimens, medications that claim to boost the metabolism, and the constant pressure to fit into society all play a role in our patient's choices regarding new dietary products. One of the products that are well known to suppress appetite and cause weight loss is amphetamines. While these medications suppress appetite, most people are not aware of the detrimental side effects of amphetamines, including hypertension, tachycardia, arrhythmias, and in certain instances acute myocardial infarction. Here we present the uncommon entity of an acute myocardial infarction due to chronic use of an amphetamine containing dietary supplement in conjunction with an exercise regimen. Our case brings to light further awareness regarding use of amphetamines. Clinicians should have a high index of suspicion of use of these substances when young patients with no risk factors for coronary artery disease present with acute arrhythmias, heart failure, and myocardial infarctions.
- Published
- 2016
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28. A systematic review of animal based indicators of sheep welfare on farm, at market and during transport, and qualitative appraisal of their validity and feasibility for use in UK abattoirs.
- Author
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Llonch P, King EM, Clarke KA, Downes JM, and Green LE
- Subjects
- Agriculture, Animal Husbandry, Animals, Feasibility Studies, Transportation, United Kingdom, Abattoirs, Animal Welfare, Sheep
- Abstract
In the UK, it has been suggested that abattoirs are ideal locations to assess the welfare of sheep as most are slaughtered at abattoirs either as finished lambs or cull ewes. Data from abattoirs could provide benchmarks for welfare indicators at a national level, as well as demonstrating how these change over time. Additionally, feedback could be provided to farmers and regulatory authorities to help improve welfare and identify high or low standards for quality assurance or risk-based inspections. A systematic review of the scientific literature was conducted, which identified 48 animal-based indicators of sheep welfare that were categorised by the Five Freedoms. Their validity as measures of welfare and feasibility for use in abattoirs were evaluated as potential measures of prior sheep welfare on the farm of origin, at market, or during transportation to the abattoir. A total of 19 indicators were considered valid, of which nine were considered theoretically feasible for assessing sheep welfare at abattoirs; these were body cleanliness, carcass bruising, diarrhoea, skin lesions, skin irritation, castration, ear notching, tail docking and animals recorded as 'obviously sick'. Further investigation of these indicators is required to test their reliability and repeatability in abattoirs. Novel welfare indicators are needed to assess short-term hunger and thirst, prior normal behaviour and long-term fear and distress., (Copyright © 2015 Elsevier Ltd. All rights reserved.)
- Published
- 2015
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29. Pomegranate extract induces ellagitannin metabolite formation and changes stool microbiota in healthy volunteers.
- Author
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Li Z, Henning SM, Lee RP, Lu QY, Summanen PH, Thames G, Corbett K, Downes J, Tseng CH, Finegold SM, and Heber D
- Subjects
- Adult, Bacteria classification, Bacteria genetics, Bacteria metabolism, Coumarins metabolism, Coumarins urine, Ellagic Acid metabolism, Ellagic Acid urine, Female, Gastrointestinal Tract metabolism, Gastrointestinal Tract microbiology, Healthy Volunteers, Humans, Male, Young Adult, Bacteria isolation & purification, Feces microbiology, Gastrointestinal Microbiome, Hydrolyzable Tannins metabolism, Lythraceae metabolism, Plant Extracts metabolism
- Abstract
The health benefits of pomegranate (POM) consumption are attributed to ellagitannins and their metabolites, formed and absorbed in the intestine by the microbiota. In this study twenty healthy participants consumed 1000 mg of POM extract daily for four weeks. Based on urinary and fecal content of the POM metabolite urolithin A (UA), we observed three distinct groups: (1) individuals with no baseline UA presence but induction of UA formation by POM extract consumption (n = 9); (2) baseline UA formation which was enhanced by POM extract consumption (N = 5) and (3) no baseline UA production, which was not inducible (N = 6). Compared to baseline the phylum Actinobacteria was increased and Firmicutes decreased significantly in individuals forming UA (producers). Verrucomicrobia (Akkermansia muciniphila) was 33 and 47-fold higher in stool samples of UA producers compared to non-producers at baseline and after 4 weeks, respectively. In UA producers, the genera Butyrivibrio, Enterobacter, Escherichia, Lactobacillus, Prevotella, Serratia and Veillonella were increased and Collinsella decreased significantly at week 4 compared to baseline. The consumption of pomegranate resulted in the formation of its metabolites in some but not all participants. POM extract consumption may induce health benefits secondary to changes in the microbiota.
- Published
- 2015
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30. Antimicrobial Activity of Pomegranate and Green Tea Extract on Propionibacterium Acnes, Propionibacterium Granulosum, Staphylococcus Aureus and Staphylococcus Epidermidis.
- Author
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Li Z, Summanen PH, Downes J, Corbett K, Komoriya T, Henning SM, Kim J, and Finegold SM
- Subjects
- Colony Count, Microbial, Fruit, Microbial Sensitivity Tests, Plant Leaves, Anti-Infective Agents pharmacology, Lythraceae, Plant Extracts pharmacology, Propionibacterium drug effects, Propionibacterium acnes drug effects, Staphylococcus aureus drug effects, Staphylococcus epidermidis drug effects, Tea
- Abstract
We used pomegranate extract (POMx), pomegranate juice (POM juice) and green tea extract (GT) to establish in vitro activities against bacteria implicated in the pathogenesis of acne. Minimum inhibitory concentrations (MIC) of 94 Propionibacterium acnes, Propionibacterium granulosum, Staphylococcus aureus, and Staphylococcus epidermidis strains were determined by Clinical and Laboratory Standards Institute-approved agar dilution technique. Total phenolics content of the phytochemicals was determined using the Folin-Ciocalteu method and the polyphenol composition by HPLC. Bacteria were identified by 16S rRNA sequence analysis. GT MIC of 400 μg/ml or less was obtained for 98% of the strains tested. 64% of P. acnes strains had POMx MICs at 50 μg/ml whereas 36% had MIC >400 μg/ml. POMx, POM juice, and GT showed inhibitory activity against all the P. granulosum strains at ≤100 μg/ml. POMx and GT inhibited all the S. aureus strains at 400 μg/ml or below, and POM juice had an MIC of 200 μg/ml against 17 S. aureus strains. POMx inhibited S. epidermidis strains at 25 μg/ml, whereas POM juice MICs were ≥200 μg/ml. The antibacterial properties of POMx and GT on the most common bacteria associated with the development and progression of acne suggest that these extracts may offer a better preventative/therapeutic regimen with fewer side effects than those currently available.
- Published
- 2015
31. Propofol-induced electroencephalographic seizures in neonatal rats: the role of corticosteroids and γ-aminobutyric acid type A receptor-mediated excitation.
- Author
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Willis J, Zhu W, Perez-Downes J, Tan S, Xu C, Seubert C, Gravenstein N, and Martynyuk A
- Subjects
- Aldosterone blood, Animals, Animals, Newborn, Corticosterone blood, Mineralocorticoid Receptor Antagonists pharmacology, Rats, Rats, Sprague-Dawley, Receptors, Glucocorticoid antagonists & inhibitors, Seizures physiopathology, Adrenal Cortex Hormones physiology, Anesthetics, Intravenous pharmacology, Electroencephalography drug effects, Propofol pharmacology, Receptors, GABA-A drug effects, Seizures chemically induced
- Abstract
Background: An imbalance between excitation and inhibition in the developing central nervous system may result in a pathophysiological outcome. We investigated the mechanistic roles of endocrine activity and γ-aminobutyric acid type A receptor (GABAAR)-mediated excitation in electroencephalographic seizures caused by the GABAAR-selective anesthetic propofol in neonatal rats., Methods: Postnatal day 4-6 Sprague Dawley rats underwent a minor surgical procedure to implant electrodes to measure electroencephalographic activity for 1 hour before and 1 hour after intraperitoneal administration of propofol (40 mg·kg). Various treatments were administered 15 minutes before administration of propofol., Results: Episodes of electroencephalographic seizures and persistent low-amplitude spikes occurred during propofol anesthesia. Multifold increases in serum levels of corticosterone (t(10) = -5.062; P = 0.0005) and aldosterone (t(10) = -5.069; P = 0.0005) were detected 1 hour after propofol administration in animals that underwent experimental manipulations identical to those used to study electroencephalographic activity. Pretreatment with bumetanide, the Na-K-2Cl cotransporter inhibitor, which diminishes GABAAR-mediated excitation, eliminated both seizure and spike electroencephalographic activities caused by propofol. Mineralocorticoid and glucocorticoid receptor antagonists, RU 28318 and RU486, depressed electroencephalographic seizures but did not affect the spike electroencephalographic effects of propofol. Etomidate, at a dose sufficient to induce loss of righting reflex, was weak at increasing serum corticosteroid levels and eliciting electroencephalographic seizures. Etomidate given to corticosterone-pretreated rat pups further increased the total duration of electroencephalographic seizures caused by administration of exogenous corticosterone (t(21) = -2.512, P = 0.0203)., Conclusions: Propofol increases systemic corticosteroid levels in neonatal rats, which along with GABAAR-mediated excitation appear to be required for propofol-induced neonatal electroencephalographic seizures. Enhancement of GABAAR activity alone may not be sufficient to elicit neonatal electroencephalographic seizures.
- Published
- 2015
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32. Pomegranate extract exhibits in vitro activity against Clostridium difficile.
- Author
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Finegold SM, Summanen PH, Corbett K, Downes J, Henning SM, and Li Z
- Subjects
- Fruit, Humans, Microbial Sensitivity Tests, Phenols analysis, Plant Extracts chemistry, Anti-Bacterial Agents pharmacology, Clostridioides difficile drug effects, Lythraceae chemistry, Phenols pharmacology, Plant Extracts pharmacology
- Abstract
Objective: To determine the possible utility of pomegranate extract in the management or prevention of Clostridium difficile infections or colonization., Method: The activity of pomegranate was tested against 29 clinical C. difficile isolates using the Clinical and Laboratory Standards Institute-approved agar dilution technique. Total phenolics content of the pomegranate extract was determined by Folin-Ciocalteau colorimetric method and final concentrations of 6.25 to 400 μg/mL gallic acid equivalent were achieved in the agar., Results: All strains had MICs at 12.5 to 25 mg/mL gallic acid equivalent range. Our results suggest antimicrobial in vitro activity for pomegranate extract against toxigenic C. difficile., Conclusion: Pomegranate extract may be a useful contributor to the management and prevention of C. difficile disease or colonization., (Copyright © 2014 Elsevier Inc. All rights reserved.)
- Published
- 2014
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33. Cathodic pseudopolarography: a new tool for the identification and quantification of cysteine, cystine and other low molecular weight thiols in seawater.
- Author
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Laglera LM, Downes J, Tovar-Sánchez A, and Monticelli D
- Subjects
- Copper chemistry, Edetic Acid chemistry, Mediterranean Sea, Molecular Weight, Seawater chemistry, Sulfur Compounds analysis, Sulfur Compounds chemistry, Cysteine analysis, Cystine analysis, Electrochemical Techniques methods, Polarography methods, Seawater analysis, Sulfhydryl Compounds analysis
- Abstract
Thiols are compounds of paramount importance in the cellular metabolism due to their double detoxifying role as radical scavengers and trace metal ligands. However, we have scarce information about their extracellular cycling as limited data are available about their concentration, stability and speciation in the aquatic medium. In natural waters, they form part of the pool of reduced sulfur substance (RSS) whose presence has been documented by voltammetric and chromatographic methods. Traditional use of cathodic stripping voltammetry (CSV) for the analysis of RSS could only give an overall concentration due to the coalescence of their CSV peaks. Recently, it has been shown that the use of multiple deposition potentials could take voltammetry of RSS to a higher level, permitting the identification and quantification of the mixtures of RSS despite showing as a single coalescent peak. Here, due to its similarity with classical pseudopolarography, we propose to rename this analytical strategy as cathodic pseudopolarography (CP) and we present for the first time its use for the analysis of mixes of low molecular weight thiols (LMWT) at the nanomolar level. Despite limitations caused by the identical behavior of some LMWT, the CP allowed to isolate the contribution of cysteine and cystine from a coalescent signal in LMWT mixtures. Sample handling with clean protocols allowed the direct determination of the cystine:cysteine ratio without sample modification. Finally, we show the application of CP to identify LMWT in seawater samples extracted from benthic chambers and suggest future applications in other areas of environmental electroanalysis., (Copyright © 2014 Elsevier B.V. All rights reserved.)
- Published
- 2014
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34. Occupational hazards for pregnant or lactating women in the orthopaedic operating room.
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Downes J, Rauk PN, and Vanheest AE
- Subjects
- Anesthetics, Inhalation toxicity, Blood-Borne Pathogens, Female, Humans, Lactation, Methylmethacrylate toxicity, Pregnancy, Radiation, Ionizing, Stress, Physiological, Occupational Exposure adverse effects, Occupational Exposure prevention & control, Operating Rooms, Orthopedics, Pregnant Women
- Abstract
Pregnant or lactating staff working in the orthopaedic operating room may be at risk of occupational exposure to several hazards, including blood-borne pathogens, anesthetic gases, methylmethacrylate, physical stress, and radiation. Because the use of proper personal protective equipment is mandatory, the risk of contamination with blood-borne pathogens such as hepatitis B, hepatitis C, and HIV is low. Moreover, effective postexposure prophylactic regimens are available for hepatitis B and HIV. In the 1960s, concerns were raised about occupational exposure to harmful chemicals in the operating room such as anesthetic gases and methylmethacrylate. Guidelines on safe levels of exposure to these chemicals and the use of personal protective equipment have helped to minimize the risks to pregnant or lactating staff. Short periods of moderate physical activity are beneficial for pregnant women, but prolonged strenuous activity can lead to increased pregnancy complications. The risk of prenatal radiation exposure during orthopaedic procedures is of concern, as well. However, proper lead protection and contamination control can minimize the risk of occupational exposure to radiation.
- Published
- 2014
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35. Xylooligosaccharide increases bifidobacteria but not lactobacilli in human gut microbiota.
- Author
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Finegold SM, Li Z, Summanen PH, Downes J, Thames G, Corbett K, Dowd S, Krak M, and Heber D
- Subjects
- Adult, Bifidobacterium metabolism, Colon metabolism, Fatty Acids, Volatile metabolism, Feces microbiology, Female, Humans, Lactobacillus metabolism, Male, Middle Aged, Young Adult, Bifidobacterium growth & development, Colon microbiology, Glucuronates metabolism, Lactobacillus growth & development, Microbiota, Oligosaccharides metabolism, Prebiotics analysis
- Abstract
This study was conducted to determine the tolerance and effects of the prebiotic xylooligosaccharide (XOS) on the composition of human colonic microbiota, pH and short chain fatty acids (SCFA) in order to determine whether significant changes in the microbiota would be achievable without side effects. Healthy adult subjects (n = 32) were recruited in a double-blind, randomized, placebo-controlled study. Subjects received 1.4 g XOS, 2.8 g XOS or placebo in daily doses. The study consisted of a 2 week run-in, an 8 week intervention, and a 2 week washout phase. Stool samples were collected at baseline, after 4 and 8 weeks of intervention and 2 weeks after cessation of intervention. Samples were subjected to culture, pyrosequencing of community DNA, pH and SCFA analyses. Tolerance was evaluated by daily symptom charts. XOS was tolerated without significant gastrointestinal side effects. Bifidobacterium counts increased in both XOS groups compared to the placebo subjects, the 2.8 g per day group showed significantly greater increases than the 1.4 g per day group. Total anaerobic counts and Bacteroides fragilis group counts were significantly higher in the 2.8 g per day XOS group. There were no significant differences in the counts of Lactobacillus, Enterobacteriaceae and Clostridium between the three groups. XOS intervention had no significant effect on stool pH, SCFA or lactic acid. Pyrosequencing showed no notable shifts in bacterial diversity. XOS supplementation may be beneficial to gastrointestinal microbiota and 2.8 g per day may be more effective than 1.4 g per day. The low dose required and lack of gastrointestinal side effects makes the use of XOS as a food supplement feasible.
- Published
- 2014
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36. 150 years of the Yorkshire Veterinary Society.
- Author
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Downes J
- Subjects
- England, History, 19th Century, History, 20th Century, History, 21st Century, Societies, Veterinary Medicine history
- Published
- 2013
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37. Description of Alloprevotella rava gen. nov., sp. nov., isolated from the human oral cavity, and reclassification of Prevotella tannerae Moore et al. 1994 as Alloprevotella tannerae gen. nov., comb. nov.
- Author
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Downes J, Dewhirst FE, Tanner ACR, and Wade WG
- Subjects
- Acetic Acid metabolism, Bacterial Typing Techniques, Base Composition, DNA, Bacterial genetics, Fatty Acids analysis, Fermentation, Humans, Molecular Sequence Data, Prevotella genetics, Prevotella isolation & purification, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Succinic Acid metabolism, Mouth microbiology, Phylogeny, Prevotella classification
- Abstract
Five strains of anaerobic, gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. Phylogenetic analysis of full-length 16S rRNA gene sequences showed that these strains represented a novel group within the family Prevotellaceae, and the most closely related species was Prevotella tannerae. P. tannerae and the novel taxon are deeply branched from the genus Prevotella, with sequence identities to the type strain of the type species of Prevotella, Prevotella melaninogenica, of 82.2 and 85.6 %, respectively. The novel genus Alloprevotella gen. nov. is proposed to accommodate the novel species Alloprevotella rava gen. nov., sp. nov. and the previously named Prevotella tannerae Moore et al. 1994 as Alloprevotella tannerae gen. nov., comb. nov. The type species is Alloprevotella tannerae. The type strain of Alloprevotella rava is 81/4-12(T) ( = DSM 22548(T) = CCUG 58091(T)) and the type strain of Alloprevotella tannerae is ATCC 51259(T) = CCUG 34292(T) = CIP 104476(T) = NCTC 13073(T). Alloprevotella rava is weakly to moderately saccharolytic and produces moderate amounts of acetic acid and major amounts of succinic acid as end products of fermentation. Strains are sensitive to 20 % bile and hydrolyse gelatin. The principal cellular long-chain fatty acids are anteiso-C15 : 0, iso-C15 : 0, C16 : 0, iso-C17 : 0 and iso-C17 : 0 3-OH. The G+C content of the DNA of the type strain is 47 mol%.
- Published
- 2013
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38. Fretibacterium fastidiosum gen. nov., sp. nov., isolated from the human oral cavity.
- Author
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Vartoukian SR, Downes J, Palmer RM, and Wade WG
- Subjects
- Acetic Acid metabolism, Bacteria genetics, Bacteria isolation & purification, Base Composition, Coculture Techniques, DNA, Bacterial genetics, Fatty Acids analysis, Humans, Molecular Sequence Data, Periodontal Pocket microbiology, Propionates metabolism, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Bacteria classification, Mouth microbiology, Phylogeny
- Abstract
SGP1(T), a strain belonging to a lineage of the phylum Synergistetes with no previously cultivated representatives was subjected to a comprehensive range of phenotypic and genotypic tests. For good growth the strain was dependent on co-culture with, or extracts from, selected other oral bacteria. Cells of strain SGP1(T) were asaccharolytic and major amounts of acetic acid and moderate amounts of propionic acid were produced as end products of metabolism in peptone-yeast extract-glucose broth supplemented with a filtered cell sonicate of Fusobacterium nucleatum subsp. nucleatum ATCC 25586(T) (25 %, v/v). Hydrogen sulphide was produced and gelatin was weakly hydrolysed. The major cellular fatty acids were C(14 : 0), C(18 : 0) and C(16 : 0). The DNA G+C content of strain SGP1(T) was 63 mol%. Phylogenetic analysis of the full-length 16S rRNA gene showed that strain SGP1(T) represented a novel group within the phylum Synergistetes. A novel species in a new genus, Fretibacterium fastidiosum gen. nov., sp. nov., is proposed. The type strain of Fretibacterium fastidiosum is SGP1(T) ( = DSM 25557(T) = JCM 16858(T)).
- Published
- 2013
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39. The influence of high intensity terahertz radiation on mammalian cell adhesion, proliferation and differentiation.
- Author
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Williams R, Schofield A, Holder G, Downes J, Edgar D, Harrison P, Siggel-King M, Surman M, Dunning D, Hill S, Holder D, Jackson F, Jones J, McKenzie J, Saveliev Y, Thomsen N, Williams P, and Weightman P
- Subjects
- Cell Adhesion radiation effects, Cell Line, Cell Proliferation radiation effects, Humans, Cell Differentiation radiation effects, Embryonic Stem Cells cytology, Embryonic Stem Cells radiation effects, Epithelial Cells cytology, Epithelial Cells radiation effects, Terahertz Radiation adverse effects
- Abstract
Understanding the influence of exposure of biological systems to THz radiation is becoming increasingly important. There is some evidence to suggest that THz radiation can influence important activities within mammalian cells. This study evaluated the influence of the high peak power, low average power THz radiation produced by the ALICE (Daresbury Laboratory, UK) synchrotron source on human epithelial and embryonic stem cells. The cells were maintained under standard tissue culture conditions, during which the THz radiation was delivered directly into the incubator for various exposure times. The influence of the THz radiation on cell morphology, attachment, proliferation and differentiation was evaluated. The study demonstrated that there was no difference in any of these parameters between irradiated and control cell cultures. It is suggested that under these conditions the cells are capable of compensating for any effects caused by exposure to THz radiation with the peak powers levels employed in these studies.
- Published
- 2013
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40. Microbiology of regressive autism.
- Author
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Finegold SM, Downes J, and Summanen PH
- Subjects
- Anti-Bacterial Agents pharmacology, Desulfovibrio drug effects, Humans, Microbial Sensitivity Tests, Autistic Disorder microbiology, Desulfovibrio isolation & purification, Desulfovibrio pathogenicity, Feces microbiology
- Abstract
This manuscript summarizes some of our earlier work on the microbiology of autism subjects' stool specimens, as compared with stools from control subjects. Our most recent data indicating that Desulfovibrio may play an important role in regressive autism is also presented. In addition, we present information on antimicrobial susceptibility patterns of Desulfovibrio using the CLSI agar dilution susceptibility technique. In addition, we summarize data from our earlier studies showing the impact of various antimicrobial agents on the indigenous bowel flora. This shows that penicillins and cephalosporins, as well as clindamycin, have a major impact on the normal bowel flora and therefore might well predispose subjects to overgrowth of such organisms as Clostridium difficile, and of particular importance for autism, to Desulfovibrio., (Published by Elsevier Ltd.)
- Published
- 2012
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41. Prevotella fusca sp. nov. and Prevotella scopos sp. nov., isolated from the human oral cavity.
- Author
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Downes J and Wade WG
- Subjects
- Anaerobiosis, Anti-Bacterial Agents metabolism, Base Composition, Bile metabolism, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Fatty Acids analysis, Hemiterpenes, Humans, Lactic Acid metabolism, Molecular Sequence Data, Pentanoic Acids metabolism, Phylogeny, Prevotella genetics, Prevotella physiology, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Succinic Acid metabolism, Sucrose metabolism, Mouth microbiology, Prevotella classification, Prevotella isolation & purification
- Abstract
Two strains of anaerobic, Gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to belong to two separate taxa. Phylogenetic analysis of full-length 16S rRNA gene sequences showed that the strains were both related to, but distinct from, the type strain of Prevotella melaninogenica. Two novel species, Prevotella fusca sp. nov. and Prevotella scopos sp. nov., are proposed to accommodate these strains. Both strains were saccharolytic and produced acetic and succinic acids, with lesser amounts of lactic and isovaleric acids, as end products of fermentation, and both were sensitive to 20 % bile. The principal cellular long-chain fatty acids of both strains were ai-C(15 : 0), 3-OH i-C(17 : 0), 3-OH C(16 : 0), i-C(15 : 0) and C(16 : 0). The DNA G+C contents of the type strains of Prevotella fusca (W1435(T) = DSM 22504(T) = CCUG 57946(T)) and Prevotella scopos (W2052(T) = DSM 22613(T ) = CCUG 57945(T)) were 43 and 41 mol%, respectively. The two species could be differentiated by gelatin hydrolysis, cellobiose and ribose fermentation, and production of β-glucosidase.
- Published
- 2011
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42. Phosphorylated dihydroceramides from common human bacteria are recovered in human tissues.
- Author
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Nichols FC, Yao X, Bajrami B, Downes J, Finegold SM, Knee E, Gallagher JJ, Housley WJ, and Clark RB
- Subjects
- Arteries microbiology, Brain microbiology, Humans, Intestines microbiology, Organ Specificity, Periodontium microbiology, Phosphorylation, Plaque, Atherosclerotic microbiology, Plasma microbiology, Toll-Like Receptor 2 metabolism, Bacteria metabolism, Ceramides isolation & purification, Ceramides metabolism
- Abstract
Novel phosphorylated dihydroceramide (PDHC) lipids produced by the periodontal pathogen Porphyromonas gingivalis include phosphoethanolamine (PE DHC) and phosphoglycerol dihydroceramides (PG DHC) lipids. These PDHC lipids mediate cellular effects through Toll-like receptor 2 (TLR2) including promotion of IL-6 secretion from dendritic cells and inhibition of osteoblast differentiation and function in vitro and in vivo. The PE DHC lipids also enhance (TLR2)-dependent murine experimental autoimmune encephalomyelitis (EAE), a model for multiple sclerosis. The unique non-mammalian structures of these lipids allows for their specific quantification in bacteria and human tissues using multiple reaction monitoring (MRM)-mass spectrometry (MS). Synthesis of these lipids by other common human bacteria and the presence of these lipids in human tissues have not yet been determined. We now report that synthesis of these lipids can be attributed to a small number of intestinal and oral organisms within the Bacteroides, Parabacteroides, Prevotella, Tannerella and Porphyromonas genera. Additionally, the PDHCs are not only present in gingival tissues, but are also present in human blood, vasculature tissues and brain. Finally, the distribution of these TLR2-activating lipids in human tissues varies with both the tissue site and disease status of the tissue suggesting a role for PDHCs in human disease.
- Published
- 2011
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43. Scardovia wiggsiae sp. nov., isolated from the human oral cavity and clinical material, and emended descriptions of the genus Scardovia and Scardovia inopinata.
- Author
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Downes J, Mantzourani M, Beighton D, Hooper S, Wilson MJ, Nicholson A, and Wade WG
- Subjects
- Acetic Acid metabolism, Actinobacteria genetics, Actinobacteria physiology, Base Composition, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Fatty Acids analysis, Fermentation, Humans, Lactic Acid metabolism, Molecular Sequence Data, Peptidoglycan chemistry, Phospholipids analysis, Phylogeny, Quinones analysis, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Actinobacteria classification, Actinobacteria isolation & purification, Gram-Positive Bacterial Infections microbiology, Mouth microbiology
- Abstract
Six strains of anaerobic, pleomorphic Gram-positive bacilli, isolated from the human oral cavity and an infected arm wound, were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. 16S rRNA gene sequence analysis revealed that the isolates were most closely related to Scardovia inopinata CCUG 35729(T) (94.8-94.9 % 16S rRNA gene sequence similarity). The isolates were saccharolytic and produced acetic and lactic acids as end products of fermentation. The major fatty acids were C(16 : 0) (49.8 %) and C(18 : 1)ω9c (35.8 %). Polar lipid analysis revealed a variety of glycolipids, diphosphatidylglycerol, an unidentified phospholipid and an unidentified phosphoglycolipid. No respiratory quinones were detected. The peptidoglycan was of the type A4α L-Lys-Thr-Glu, with L-lysine partially replaced by L-ornithine. The DNA G+C content of one of the strains, C1A_55(T)(,) was 55 mol%. A novel species, Scardovia wiggsiae sp. nov., is proposed to accommodate the six isolates, with the type strain C1A_55(T) (=DSM 22547(T)=CCUG 58090(T)).
- Published
- 2011
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44. Prevotella saccharolytica sp. nov., isolated from the human oral cavity.
- Author
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Downes J, Tanner ACR, Dewhirst FE, and Wade WG
- Subjects
- Acetic Acid metabolism, Bacterial Typing Techniques, Base Composition, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Fatty Acids analysis, Fermentation, Humans, Molecular Sequence Data, Phylogeny, Prevotella genetics, Prevotella physiology, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Succinic Acid metabolism, Sucrose metabolism, Mouth microbiology, Prevotella classification, Prevotella isolation & purification
- Abstract
Two strains of anaerobic, Gram-stain-negative bacilli isolated from the human oral cavity (D033B-12-2(T) and D080A-01) were subjected to a comprehensive range of phenotypic and genotypic tests and were found to be distinct from any previously described species. 16S rRNA gene sequence analysis revealed that the strains were related most closely to the type strain of Prevotella marshii (93.5 % sequence identity). The novel strains were saccharolytic and produced acetic acid and succinic acid as end products of fermentation. The principal cellular long-chain fatty acids were C₁₆ :₀), iso-C₁₄:₀, C₁₄:₀, anteiso-C₁₅:₀, iso-C₁₆ :₀ and C₁₆:₀) 3-OH. The G+C content of the DNA of strain D033B-12-2(T) was 44 mol%. Strains D033B-12-2(T) and D080A-01 are considered to represent a single novel species of the genus Prevotella, for which the name Prevotella saccharolytica sp. nov. is proposed. The type strain is D033B-12-2(T) (=DSM 22473(T) =CCUG 57944(T)).
- Published
- 2010
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45. Propionibacterium acidifaciens sp. nov., isolated from the human mouth.
- Author
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Downes J and Wade WG
- Subjects
- DNA, Bacterial genetics, DNA, Ribosomal genetics, Humans, Molecular Sequence Data, Phylogeny, Propionibacterium genetics, RNA, Ribosomal, 16S genetics, Mouth microbiology, Propionibacterium classification, Propionibacterium isolation & purification
- Abstract
Three strains of anaerobic, pleomorphic, Gram-positive-staining bacilli, which were isolated from human carious dentine, were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. The strains were saccharolytic and produced acetic and propionic acids in large amounts, and succinic acid in moderate amounts, as the end products of fermentation. 16S rRNA gene and RpoB protein sequence analyses revealed that the strains constituted a novel group within the genus Propionibacterium, most closely related to Propionibacterium australiense but sharing only 8 % DNA-DNA relatedness with the type strain of that species. Therefore, a novel species, Propionibacterium acidifaciens sp. nov., is proposed to accommodate these strains. The DNA G+C content of the type strain is 70 mol%. The type strain is C3M_31(T) (=DSM 21887(T) =CCUG 57100(T)).
- Published
- 2009
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46. Pyramidobacter piscolens gen. nov., sp. nov., a member of the phylum 'Synergistetes' isolated from the human oral cavity.
- Author
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Downes J, Vartoukian SR, Dewhirst FE, Izard J, Chen T, Yu WH, Sutcliffe IC, and Wade WG
- Subjects
- Bacteria, Anaerobic genetics, Bacteria, Anaerobic isolation & purification, Bacteria, Anaerobic physiology, Bacterial Typing Techniques, Base Composition, DNA, Bacterial analysis, DNA, Ribosomal analysis, Genotype, Gram-Negative Bacteria genetics, Gram-Negative Bacteria isolation & purification, Gram-Negative Bacteria physiology, Humans, Molecular Sequence Data, Phenotype, Phylogeny, RNA, Ribosomal, 16S genetics, RNA, Ribosomal, 23S genetics, Sequence Analysis, DNA, Species Specificity, Bacteria, Anaerobic classification, Gingivitis microbiology, Gram-Negative Bacteria classification, Gram-Negative Bacterial Infections microbiology, Mouth microbiology, Periodontal Pocket microbiology
- Abstract
Four strains of anaerobic, Gram-negative bacilli isolated from the human oral cavity were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group distinct from any species with validly published names. 16S rRNA and 23S rRNA gene sequence analyses and DNA-DNA reassociation data revealed that the strains constituted a novel group within the phylum 'Synergistetes' and were most closely related to Jonquetella anthropi. Two libraries of randomly cloned DNA were prepared from strain W5455(T) and were sequenced to provide a genome survey as a resource for metagenomic studies. A new genus and novel species, Pyramidobacter piscolens gen. nov., sp. nov., is proposed to accommodate these strains. The genus Pyramidobacter comprises strains that are anaerobic, non-motile, asaccharolytic bacilli that produce acetic and isovaleric acids and minor to trace amounts of propionic, isobutyric, succinic and phenylacetic acids as end products of metabolism. P. piscolens gen. nov., sp. nov. produced hydrogen sulphide but was otherwise largely biochemically unreactive. Growth was stimulated by the addition of glycine to broth media. The G+C content of the DNA of the type strain was 59 mol%. The type strain of Pyramidobacter piscolens sp. nov. is W5455(T) (=DSM 21147(T)=CCUG 55836(T)).
- Published
- 2009
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47. Prevotella micans sp. nov., isolated from the human oral cavity.
- Author
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Downes J, Liu M, Kononen E, and Wade WG
- Subjects
- Bacterial Typing Techniques, Base Composition, Cluster Analysis, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Humans, Molecular Sequence Data, Phylogeny, Prevotella genetics, Prevotella physiology, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Sequence Homology, Nucleic Acid, Mouth microbiology, Prevotella classification, Prevotella isolation & purification
- Abstract
Four strains of anaerobic Gram-negative bacilli isolated from the human mouth were characterized using a variety of phenotypic and genotypic tests. The strains were found to comprise a homogeneous group and 16S rRNA gene sequence analysis revealed them to be distinct from but related to a loose cluster of Prevotella species including Prevotella buccalis, Prevotella nanceiensis and Prevotella marshii. A novel species, Prevotella micans sp. nov., is proposed to accommodate these strains. Prevotella micans is saccharolytic and produces acetic, isovaleric and succinic acids and minor amounts of isobutyric acid as end products of fermentation. The G+C content of the DNA of the type strain is 46 mol%. The type strain of Prevotella micans is E7.56(T) (=DSM 21469(T )=CCUG 56105(T)).
- Published
- 2009
- Full Text
- View/download PDF
48. Electronic structure of the organic semiconductor Alq3 (aluminum tris-8-hydroxyquinoline) from soft x-ray spectroscopies and density functional theory calculations.
- Author
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DeMasi A, Piper LF, Zhang Y, Reid I, Wang S, Smith KE, Downes JE, Peltekis N, McGuinness C, and Matsuura A
- Abstract
The element-specific electronic structure of the organic semiconductor aluminum tris-8-hydroxyquinoline (Alq(3)) has been studied using a combination of resonant x-ray emission spectroscopy, x-ray photoelectron spectroscopy, x-ray absorption spectroscopy, and density functional theory (DFT) calculations. Resonant and nonresonant x-ray emission spectroscopy were used to measure directly the carbon, nitrogen and oxygen 2p partial densities of states in Alq(3), and good agreement was found with the results of DFT calculations. Furthermore, resonant x-ray emission at the carbon K-edge is shown to be able to measure the partial density of states associated with individual C sites. Finally, comparison of previous x-ray emission studies and the present data reveal the presence of clear photon-induced damage in the former.
- Published
- 2008
- Full Text
- View/download PDF
49. Prevotella histicola sp. nov., isolated from the human oral cavity.
- Author
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Downes J, Hooper SJ, Wilson MJ, and Wade WG
- Subjects
- Acetic Acid metabolism, Bacterial Typing Techniques, Base Composition, DNA, Bacterial analysis, DNA, Ribosomal analysis, Genes, rRNA, Genotype, Humans, Molecular Sequence Data, Nucleic Acid Hybridization, Phenotype, Phylogeny, Prevotella genetics, Prevotella isolation & purification, Prevotella metabolism, RNA, Ribosomal, 16S, Sequence Analysis, DNA, Species Specificity, Succinic Acid metabolism, Carcinoma, Squamous Cell microbiology, Mouth Mucosa microbiology, Mouth Neoplasms microbiology, Prevotella classification
- Abstract
Three strains of anaerobic, variably pigmenting, Gram-negative bacilli isolated from human oral mucosal tissue were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. 16S rRNA gene sequence analysis and DNA-DNA hybridization revealed that the strains constituted a novel group within the genus Prevotella, being most closely related to Prevotella melaninogenica and Prevotella veroralis. A novel species, Prevotella histicola sp. nov., is proposed to accommodate these strains. Prevotella histicola is saccharolytic and produces acetic acid and succinic acid as major end products of fermentation and trace to minor amounts of isovaleric acid and lactic acid. The G+C content of the DNA of the type strain is 43 mol%. The type strain of Prevotella histicola is T05-04T (=DSM 19854T=CCUG 55407T).
- Published
- 2008
- Full Text
- View/download PDF
50. Prevotella maculosa sp. nov., isolated from the human oral cavity.
- Author
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Downes J, Sutcliffe IC, Booth V, and Wade WG
- Subjects
- Acetic Acid metabolism, Anaerobiosis physiology, Bacterial Typing Techniques, Base Composition, Carbohydrate Metabolism, DNA, Bacterial chemistry, DNA, Bacterial genetics, DNA, Ribosomal chemistry, DNA, Ribosomal genetics, Genes, rRNA, Humans, Molecular Sequence Data, Phylogeny, Prevotella genetics, Prevotella metabolism, RNA, Ribosomal, 16S genetics, Sequence Analysis, DNA, Sequence Homology, Nucleic Acid, Succinic Acid metabolism, Mouth microbiology, Prevotella classification, Prevotella isolation & purification
- Abstract
Three strains of anaerobic Gram-negative bacilli isolated from human oral sites were subjected to a comprehensive range of phenotypic and genotypic tests and were found to comprise a homogeneous group. 16S rRNA gene sequence analysis revealed the strains to constitute a novel group within the genus Prevotella, most closely related to Prevotella oris and Prevotella salivae. A novel species, Prevotella maculosa sp. nov., is proposed to accommodate these strains. Prevotella maculosa is saccharolytic and produces acetic and succinic acids as end products of fermentation. The G+C content of the DNA of the type strain is 48 mol%. The type strain of Prevotella maculosa is W1609(T) (=DSM 19339(T) =CCUG 54766(T)).
- Published
- 2007
- Full Text
- View/download PDF
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