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Unexplained Fever Associated With Hypersensitivity and Auto-Immune Diseases
Published in Benedict Isaac, Serge Kernbaum, Michael Burke, Unexplained Fever, 2019
Anti-DNA antibodies — Two techniques are usually performed. The radioimmuno-logical Farr test (which uses immunoglobulin (IgG) precipitation by ammonium sulfate) is a sensitive detector of all antibodies capable of binding to DNA, independent of their biological properties. It is positive in 80 to 98% of SLE cases, in 0 to 6% of patients with rheumatoid arthritis and in 0 to 2% of normal subjects.2 The second technique used in the routine clinical detection is an immunofluorescent method detecting antibodies to double-stranded DNA employing the kinetoplast of the flagellate Crithidia luciliae as a substrate. It allows determination of the antibodies according to their nature (IgG, IgM, IgA) and their complement fixing ability (IgGl, IgG3); it may give false-positive results; it is positive in up to 96% of SLE sera.2 Then the diagnosis of SLE relies on the association of evocative clinical lesions with immune abnormalities.
Macro and Micro Algal Impact on Marine Ecosystem
Published in Gokare A. Ravishankar, Ranga Rao Ambati, Handbook of Algal Technologies and Phytochemicals, 2019
Almost three-quarters of the Earth’s surface is covered by the oceans where algae form the base of the food chain. Phytoplanktons account for nearly half of global primary production (~500 × 1015 g of carbon fixed/year) (Falkowski 1994), although they constitute less than 1% of the world’s photosynthetic biomass (Falkowski 2000, Chrisholm et al. 2001). Enormous variation in size exists in phytoplankton communities. Seiburth’s (1979) method of for classifying phytoplankton based on their size as per logarithmic scale is widely accepted. Plankton whose size exceeds 200 µm are classified as mesoplankton, between 20–100 µm as microplankton. Smaller than the microplankton comes the nanoplanktons (2–20 µm) and picoplankton (0.2–2 µm). Of these various types, the “Classical” phytoplankton is constituted by the microplankton—majorly the Dinophytes and Bacillariophytes. A variety of pigmented flagellates including Prasinophytes, Chrysophytes, Cryptomonads, Haptophytes as well as a few Dinoflagellates, Euglenoids, tiny Bacillariophytes and Chlorophytes constitute the nanophytoplankton. Prokaryotes are the principal constituents of the picophytoplankton although a few eukaryotes especially the Chlorophytes are small enough to be included in this group.
The Protozoa
Published in Donald L. Price, Procedure Manual for the Diagnosis of Intestinal Parasites, 2017
Their means of locomotion are flagella, and the shape of the body affects the movement pattern through the medium in which the flagellate resides. Chilomastix swims in a spiral motion, Trichomonas moves in circles, and Giardia moves with a rocking motion in a more or less straight line. When looking at a fresh specimen in which there are active trophozoites of a species of flagellate, the type of movement helps in making an identification.
Shiitake dermatitis: experience of the Poison Control Centre Network in France from 2014 to 2019
Published in Clinical Toxicology, 2022
David Boels, Chloé Greillet, Jérôme Langrand, Magali Labadie, Gaël Le Roux, Luc de Haro, Juliette Bloch, Sandra Sinno-Tellier
Nguyen et al. propose another mechanism and postulate that genetically susceptible individuals with certain human leukocyte antigen alleles require exposure to large amounts of lentinan in order to be sensitised [10]. The immunomodulating properties of lentinan have been shown to induce vasodilation and haemorrhage, skewing the immune system towards a Th1-type response [21–23]. This is also consistent with proposed mechanisms of bleomycin-induced flagellate erythema [24]. This phenomenon has been noted in the sensitisation process of individuals using squaric acid, in which a cutaneous hypersensitivity reaction has been found to be dose dependent [25]. Our study suggests a dose-dependent response which could be explained by a partial toxic mechanism, but also a th1-type hypersensitivity mechanism proposed by Nguyen et al. Experimental research as well as future investigations regarding potential genetic considerations in patients, and information on the culture conditions of shiitake (media, region), will be needed to confirm these hypotheses.
Influence of abiotic conditions on the biofouling formation of flagellated microalgae culture
Published in Biofouling, 2022
Lucía García-Abad, Lorenzo López-Rosales, María del Carmen Cerón-García, Marta Fernández-García, Francisco García-Camacho, Emilio Molina-Grima
Flagellated microalgae are also of interest when studying adhesion since the flagella themselves are responsible for the microalgae interacting with the surface. Changes can be made to the culture conditions, such as the light intensity and wavelength within the visible spectra (Kreis et al. 2018), causing them to reposition, thus, decreasing the adhesion forces and leading to less biofouling formation. According to Xiao and Zheng (2016), the nitrogen-to-phosphorus ratio affects the cells in terms of producing EPS compounds; as with the light intensity parameter, this has a significant influence on EPS production (Cordoba Castro et al. 2012), which, in turn, influences biofilm formation. Adjusting the N/P ratio could be an interesting way to modulate protein production (and EPS in general) in N. gaditana cultures, as described by Soriano-Jerez et al. (2021). Avoiding early protein binding should be a preliminary step in designing or selecting materials and coatings for photobioreactor fabrication. Moreover, the physicochemical characteristics of the PBR construction materials themselves influence biofouling formation.
Toward a porcine in vivo model to analyze the pathogenesis of TLR5-dependent enteropathies
Published in Gut Microbes, 2020
Robert Pieper, Niels van Best, Kira van Vorst, Friederike Ebner, Monika Reissmann, Mathias W. Hornef, Marcus Fulde
Interestingly, variants in the TLR5 locus were also found in other animals, e.g. in the German shepherd dog. Notably, also here an association between inherited TLR5 dysfunction and protection from IBD and other enteropathies was established.25,26 Furthermore, the pig breed “Deutsche Landrasse” harbors an SNP in TLR5, which is inherited recessively on chromosome 10 and leads to a P402L amino acid change causing impaired recognition of Salmonella and flagellin, respectively.27 This SNP does not lead to an entirely dysfunctional TLR5 but has been shown to reduce downstream NF-κB activation by about one-third as compared to the wildtype TLR5 allele.28 Consistently, the impaired flagellin recognition in the pig may confer an increased susceptibility to flagellated bacteria, such as Salmonella Typhimurium and (entero-)pathogenic E. coli.29–31 The latter observation opens the possibility for further investigations of the functional role of TLR5-signaling in mucosal inflammation in a model that mimics the human situation more closely and may additionally allow the evaluation of potential preventive measures and therapeutic strategies. Pigs share key similarities with humans, such as body size, anatomical features, (patho-)physiological responses and diet.32 Also, the microbiota of humans is more similar to the microbiota of pigs than rodent animals.33 This is particularly important since microbiota alterations appear to play a functional role.12