598 research outputs found

    The biochemical, morphological and virulence profiles of Bacillus anthracis isolated in the Kruger National Park

    Get PDF
    The biochemical, morphological and virulence profiles of 44 Bacillus anthracis isolates, obtained from various localities and carcass remains of wild animals in the Kruger National Park, South Africa, were examined. The morphological characteristics tested for included: the formation of capsules on bicarbonate agar, the motility of the vegetative organism, the presence of haemolysis on blood tryptose agar, the sensitivity of the vegetative organism to bacteriophage, the production of lecithinase on egg yolk agar, the liquefaction (hydrolysis) of gelatine and the capability of each isolate to produce mucoid colonies when grown on bicarbonate agar with horse serum in an atmosphere containing C0₂. The API 50CHB and 20E systems were used to evaluate the biochemical activity of each isolate. The virulence of each isolate was determined by its LD50, using an inbred line of Balb/C mice. A clear pattern in the biochemical reactions emerged that appeared to be specific for each isolate. On the API 50CHB test strip, only 2 of the 44 isolates gave a 100% positive reaction to all 10 of the biochemical substances to which it was supposed to react, 9 gave positive results to 90%, 19 were positive to 80%, and 14 were positive to 70%. The reactions on the API 20E were completely different from what was expected, with only 1 of the biochemical activities (gelatinase production) showing a positive reaction to all the isolates. The virulence test indicated that 27/44 isolates could be regarded as highly virulent with a LD50 of <1 000 organisms, and the rest of the isolates as virulent with a LD 50 of 1 001 - 10 000 organisms. The other morphological characteristics demonstrated the typical nature of Bacillus anthracis. Three control isolates, one being the non-capsular, avirulent toxigenic Sterne strain were included in this study.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

    The antibiotic sensitivity patterns of Bacillus anthracis isolated from the Kruger National Park

    Get PDF
    Forty-four isolates of Bacillus anthracis made from carcasses and soil in different localities of an endemic anthrax area in the Kruger National Park, South Africa, were tested by standard disc diffusion for their susceptibility to 18 different antibiotics. These were ampicillin, penicillin G, sulphatriad, streptomycin, clindamycin, gentamicin, fusidic acid, trimethoprim, sulphamethoxazole, chloramphenicol, erythromycin, methicillin, tetracycline (2 different concentrations), novobiocin, cefotaxime, netilmicin, cefamandole and cefoxitin. All the isolates were susceptible to ampicillin, streptomycin, chloramphenicol erythromycin, tetracycline, methicillin and netilmicin. More than 90% of the isolates were sensitive to clindamycin, gentamicin and cefoxitin, whereas only 84,1% of the isolates were sensitive to penicillin G, 86,4% to novobiocin and 68,18% to cefamandole. Complete resistance in 100% of the isolates was encountered with trimethoprim and sulphamethoxazole, with 95,45% for sulphatriad. Moderate sensitivity occurred with penicillin G (15,9% of the isolates), clindamycin (6,8%), novobiocin (13,6%), fusidic acid (84,1 % ), cefotaxime (100%), cefamandole (31,8%) and cefoxitin (6,8%). The relevance of the findings to the therapeutic uses of different types of antibiotic in human clinical cases referred to in the literature is discussed.The articles have been scanned in colour with a HP Scanjet 5590; 600dpi. Adobe Acrobat XI Pro was used to OCR the text and also for the merging and conversion to the final presentation PDF-format.mn201

    Characterisation of puroindoline genes in wild tetraploid and hexaploid wheats (Triticum araraticum; T. timopheevii and T. zhukovskyi)

    Get PDF
    Treatment with cisplatin-containing chemotherapy regimens causes hearing loss in 40-60% of cancer patients. It has been suggested that genetic variants in the genes encoding thiopurine S-methyltransferase (TPMT) and catechol O-methyltransferase (COMT) can predict the development of cisplatin-induced ototoxicity and may explain interindividual variability in sensitivity to cisplatin-induced hearing loss. Two recently published studies however, sought to validate these findings and showed inconsistent results. The aim of this study was to evaluate the role of polymorphisms in the TPMT and COMT genes in cisplatin-induced ototoxicity. Therefore we investigated two independent cohorts of 110 Dutch and 38 Spanish patients with osteosarcoma and performed a meta-analysis including all previously published studies resulting in a total population of 664 patients with cancer. With this largest meta-analysis performed to date, we show that the influence of TPMT and COMT on the development of cisplatin-induced hearing loss may be less important than previously suggested

    A versatile Plasmodium falciparum reporter line expressing NanoLuc enables highly sensitive multi-stage drug assays

    Get PDF
    Presentation of a versatile Plasmodium falciparum dual reporter line, expressing both a fluorescent protein and NanoLuc under a constitutive promoter, that can be used to screen for novel anti-malarial drugs effective against multiple stages of the parasite.Transgenic luciferase-expressing Plasmodium falciparum parasites have been widely used for the evaluation of anti-malarial compounds. Here, to screen for anti-malarial drugs effective against multiple stages of the parasite, we generate a P. falciparum reporter parasite that constitutively expresses NanoLuciferase (NanoLuc) throughout its whole life cycle. The NanoLuc-expressing P. falciparum reporter parasite shows a quantitative NanoLuc signal in the asexual blood, gametocyte, mosquito, and liver stages. We also establish assay systems to evaluate the anti-malarial activity of compounds at the asexual blood, gametocyte, and liver stages, and then determine the 50% inhibitory concentration (IC50) value of several anti-malarial compounds. Through the development of this robust high-throughput screening system, we identify an anti-malarial compound that kills the asexual blood stage parasites. Our study highlights the utility of the NanoLuc reporter line, which may advance anti-malarial drug development through the improved screening of compounds targeting the human malarial parasite at multiple stages.Host-parasite interactio

    Discourse Semantics for the Analysis of Change in Language

    Get PDF
    This paper purports to elaborate and address several issues which lie at the intersection of computational linguistics and psychology. The first issue addressed is that of the interaction between discourse and semantics by virtue of empirical linguistic and psychotherapeutic evidence. This paper then gives a formal account of the knowledge representation and reasoning processes involved in the construction of an XML knowledge base for use in the sematic analysis of psychotherapeutic transcripts. Computational methods for the automatic mark-up and inference of the psychotherapeutic phenomena under investigation are detailed in order to further develop intuitions behind a particular pragmatic theory of language known as the Metamodel. The work presented here ultimately aims to produce a sustainable system for the evaluation of the effectiveness of any given psychotherapeutic technique. The possibility exists for such a system to recognise successful therapeutic mechanisms and further still, to infer new ones, or suggest improvements, or offer novel explanations as to the success or failure of the therapy itself. The work discussed here stems from research in computational linguistics, psychotherapy, and philosophy. The corpus used is a culmination of client transcripts taken before, during, and after therapy. The particular therapeutic technique used here is known as the Metamodel (Bandler and Grinder, 1975). The Metamodel was originally proffered as a method of language analysis suitable for use by practitioners of any psychotherapeutic technique. It theorises that speech utterances are related to a clients deep structure through three primary mechanisms, namely generalisation, deletion, and distortion. Previous hand tagging of our data has proven support for such claims. It is our aim to automate the identification and reasoning process. The issues and processes involved in the automation of such tagging are discussed here. Architectural and philosophical issues relating syntax (or grammar), semantics (Larson and Segal, 1995), and pragmatics (Grice, 1989; Searle, 1969) are raised. Discourse Representation Theory (Kamp, 1981; Asher and Lascarides, 1995) is discussed and used here in order to infer discourse relations.Hosted by the Scholarly Text and Imaging Service (SETIS), the University of Sydney Library, and the Research Institute for Humanities and Social Sciences (RIHSS), the University of Sydney

    Erratum:The behavioral and psychological symptoms of dementia in down syndrome scale (BPSD-DS II): Optimization and further validation

    Get PDF
    BACKGROUND: People with Down syndrome (DS) are at high risk to develop Alzheimer's disease dementia (AD). Behavioral and psychological symptoms of dementia (BPSD) are common and may also serve as early signals for dementia. However, comprehensive evaluation scales for BPSD, adapted to DS, are lacking. Therefore, we previously developed the BPSD-DS scale to identify behavioral changes between the last six months and pre-existing life-long characteristic behavior. OBJECTIVE: To optimize and further study the scale (discriminative ability and reliability) in a large representative DS study population. METHODS: Optimization was based on item irrelevance and clinical experiences obtained in the initial study. Using the shortened and refined BPSD-DS II, informant interviews were conducted to evaluate 524 DS individuals, grouped according to dementia status: no dementia (DS, N = 292), questionable dementia (DS + Q, N = 119), and clinically diagnosed dementia (DS + AD, N = 113). RESULTS: Comparing item change scores between groups revealed prominent changes in frequency and severity for anxious, sleep-related, irritable, restless/stereotypic, apathetic, depressive, and eating/drinking behavior. For most items, the proportion of individuals displaying an increased frequency was highest in DS + AD, intermediate in DS + Q, and lowest in DS. For various items within sections about anxious, sleep-related, irritable, apathetic, and depressive behaviors, the proportion of individuals showing an increased frequency was already substantial in DS + Q, suggesting that these changes may serve as early signals of AD in DS. Reliability data were promising. CONCLUSION: The optimized scale yields largely similar results as obtained with the initial version. Systematically evaluating BPSD in DS may increase understanding of changes among caregivers and (timely) adaptation of care/treatment

    The formation of cupper transition nano-layer in polytetrafluoroethylene surface by means of ion beam assisting deposition

    Get PDF
    The deposition of Cu on polytetrafluoroethylene surface assisted by the Ar ion beam with the temperature of 1 keV is investigated numerically. Ar ions provide the kinematic mixing of Cu atoms and atoms of substrate forming the connecting 10 nm layer of mixed material. This layer can ensure a good adhesion of Cu films deposited on polytetrafluoroethylene.Осаждение медного покрытия на поверхность политетрафторэтилена, стимулированное пучком ионов аргона с температурой 1 кэВ, изучалось методами численного моделирования. Ионы аргона обеспечивали смешивание атомов меди и поверхности, что позволило сформировать переходной слой шириной 10 нм. Такой слой может обеспечить хорошие адгезионные свойства металлической пленки, осажденной на поверхность политетрафторэтилена.Осадження мідного покриття на поверхню політетрафторетилену, стимульоване пучком іонів аргону з температурою 1 кеВ, вивчалось методами чисельного моделювання. Іони аргону забезпечували змішування атомів міді і поверхні, що дозволило сформувати перехідний шар шириною 10 нм. Такий шар може забезпечити гарні адгезійні властивості металевої плівки, обложеної на поверхню політетрафторетилену

    Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS

    Get PDF
    We present the results of a search for new, heavy particles that decay at a significant distance from their production point into a final state containing charged hadrons in association with a high-momentum muon. The search is conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS detector operating at the Large Hadron Collider. Production of such particles is expected in various scenarios of physics beyond the standard model. We observe no signal and place limits on the production cross-section of supersymmetric particles in an R-parity-violating scenario as a function of the neutralino lifetime. Limits are presented for different squark and neutralino masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final version to appear in Physics Letters
    corecore