Search results for "toxin"
showing 10 items of 1434 documents
Sapotrophical development of fusarium graminearum : respective role of different natural habitats of the fungus in the wheat infectious process in Bu…
2012
Fusarium Head Blight (FHB), mainly caused by the fungal species Fusarium graminearum, is one of the most important disease altering wheat crops in Burgundy. Moreover the plant-pathogen interaction leads to the production of mycotoxins potentially toxic for humans and animals.The only alternative to date to prevent the development of the disease is to control the saprotrophic development of F. graminearum in its natural habitat, i.e. weeds, soil and crops residues. Due to the trend of reduced tillage, special attention should be paid to the role of crop residues in the survival and development of F. graminearum.Two approaches were chosen to better understand the saprotrophic development of F…
A European Multi Lake Survey dataset of environmental variables, phytoplankton pigments and cyanotoxins
2018
Under ongoing climate change and increasing anthropogenic activity, which continuously challenge ecosystem resilience, an in-depth understanding of ecological processes is urgently needed. Lakes, as providers of numerous ecosystem services, face multiple stressors that threaten their functioning. Harmful cyanobacterial blooms are a persistent problem resulting from nutrient pollution and climate-change induced stressors, like poor transparency, increased water temperature and enhanced stratification. Consistency in data collection and analysis methods is necessary to achieve fully comparable datasets and for statistical validity, avoiding issues linked to disparate data sources. The Europea…
Temperature-related changes in polar cyanobacterial mat diversity and toxin production
2012
This study documents the effects of warming on cyanobacterial mats from the Arctic and Antarctica. It describes toxin production in such mats and provides experimental evidence that increased temperatures could shift mat cyanobacterial species diversity from cold-loving species towards predominance of cold-tolerant and toxin-producing species.
Effect of a Killer Toxin of Yeast on Eucaryotic Systems
1988
The Saccharomyces cerevisiae killer toxin KT 28, which inhibits sensitive yeasts, was shown to have no effect on several pathogenic fungi or on the protozoan Trichomonas vaginalis. At concentrations of about 0.1 mg/ml, a partial inhibition of the skin pathogenic fungi Trichophyton rubrum and Microsporum canis was observed at pH 6.5. No pharmacological activity was detected in various tests with several animal organs.
Lateral pterygoid muscle dystonia. A new technique for treatment with botulinum toxin guided by electromyography and arthroscopy
2010
Lateral pterygoid muscle dystonia is characterized by mandibular displacement towards the opposite side of the affected muscle. It may be associated with functional disorders affecting speech, swallowing, chewing and facial symmetry. Injection with botulinum toxin is recognized as the most effective treatment. Locating the lower head of the lateral pterygoid muscle for the injection is not difficult using electromyographic guidance; however, location of the upper head is more complicated, even with electromyography. We report a case of lateral pterygoid muscle dystonia in which precise injection of the upper head was achieved with the aid of arthroscopy.
Analysis of enniatins and beauvericin by LC-MS/MS in wheat-based products
2017
Due to the matrix complexity for wheat-based products, a comparative study of different rapid extraction procedures was performed for the extraction of enniatins (ENA, ENA1, ENB, ENB1) and beauvericin in flour, pasta, breakfast cereals, and biscuits. Three different approaches were studied during the extraction and purification steps (shaker, Ultra-Turrax, and QuEChERS) for each matrix. Liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with electrospray source working in a positive mode was used. For the analysis of the five mycotoxins, the three methods were tested in terms of recovery, matrix effect, and sensibility, concluding that Ultra-Turrax extraction was the most …
Protection from experimental allergic encephalomyelitis by application of a bacterial superantigen
1992
Certain bacterial and viral T cell stimulating proteins ('superantigens') are known to be very potent activators of T cells with certain V beta receptors. When applied in vivo these molecules induce anergy in those T cells responding to them. In this study we have investigated the influence of staphylococcal enterotoxins (SE) on myelin basic protein (MBP)-specific T cells in Lewis rats. As MBP-specific T cells in rats belong exclusively to the V beta 8.2+ CD4+ subset, the induction of experimental allergic encephalomyelitis (EAE) allows for an estimation of the functional state of the respective V beta-bearing T cells after enterotoxin-induced activation. In vitro, various MBP-specific T ce…
Characterization of the cleavage site and function of resulting cleavage fragments after limited proteolysis of Clostridium difficile toxin B (TcdB) …
2005
Clostridium difficiletoxin B (TcdB) is a single-stranded protein consisting of a C-terminal domain responsible for binding to the host cell membrane, a middle part involved in internalization, and the N-terminal catalytic (toxic) part. This study shows that TcdB is processed by a single proteolytic step which cleaves TcdB10463between Leu543and Gly544and the naturally occurring variant TcdB8864between Leu544and Gly545. The cleavage occurs at neutral pH and is catalysed by a pepstatin-sensitive protease localized in the cytoplasm and on the cytoplasmic face of intracellular membranes. The smaller N-terminal cleavage products [63 121 Da (TcdB10463) and 62 761 Da (TcdB8864)] harbour the cytotox…
Structural and functional role of Domain I for the insecticidal activity of the Vip3Aa protein from Bacillus thuringiensis
2022
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Activation of Bacillus thuringiensis Cry1I to a 50 kDa stable core impairs its full toxicity to Ostrinia nubilalis
2021
Abstract Bacillus thuringiensis Cry1I insecticidal proteins are structurally similar to other three-domain Cry proteins, although their size, activity spectrum, and expression at the stationary phase are unique among other members of the Cry1 family. The mode of action of Cry1 proteins is not completely understood but the existence of an activation step prior to specific binding is widely accepted. In this study, we attempted to characterize and determine the importance of the activation process in the mode of action of Cry1I, as Cry1Ia protoxin or its partially processed form showed significantly higher toxicity to Ostrinia nubilalis than the fully processed protein either activated with …