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201.
Timucin AVAR Gke ELKYAPI ERDEM Gkhan TERZOLU Eda TAHR TURANLI 《Turkish Journal of Biology》2021,45(5):644
Cuprizone, copper chelator, treatment of mouse is a toxic model of multiple sclerosis (MS) in which oligodendrocyte death, demyelination and remyelination can be observed. Understanding T and B cell subset as well as their cytokines involved in MS pathogenesis still requires further scrutiny to better understand immune component of MS. The study presented here, aimed to evaluate relevant cytokines, lymphocytes, and gene expressions profiles during demyelination and remyelination in the cuprizone mouse model of MS. Eighty male C57BL/6J mice fed with 0.2% cuprizone for eight weeks. Cuprizone has been removed from the diet in the following eight weeks. Cuprizone treated and control mice sacrificed biweekly, and corpus callosum of the brain was investigated by staining. Lymphocyte cells of mice analyzed by flow cytometry with CD3e, CD11b, CD19, CD80, CD86, CD4, CD25 and FOXP3 antibodies. IFN-gamma, IL-1alpha, IL-2, IL-5, IL-6, IL-10, IL-17, TNF-alpha cytokines were analyzed in plasma samples. Neuregulin 1 (Nrg1), ciliary neurotrophic factor (Cntf) and C-X-C chemokine receptor type 4 (Cxcr4) gene expressions in corpus callosum sections of the mice brain were quantified. Histochemistry analysis showed that demyelination began at the fourth week of cuprizone administration and total demyelination occurred at the twelfth week in chronic model. Remyelination occurred at the fourth week of following withdrawal of cuprizone from diet. The level of mature and activated T cells, regulatory T cells, T helper cells and mature B cells increased during demyelination and decreased when cuprizone removed from diet. Further, both type 1 and type 2 cytokines together with the proinflammatory cytokines increased. The level of oligodendrocyte maturation and survival genes showed differential gene expression in parallel to that of demyelination and remyelination. In conclusion, for the first-time, involvement of both cellular immune response and antibody response as well as oligodendrocyte maturation and survival factors having role in demyelination and remyelination of cuprizone mouse model of MS have been shown. 相似文献
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During the Early Permian, in the area of the Carnic Alps, a quartz-gravelly beach fringed a mixed siliciclastic-carbonate lagoon with fleshy algal meadows and oncoids; seaward, an ooid shoal belt graded down dip to a low-energy carbonate inner shelf with phylloid algal meadows. In limestones, foraminiferal biomurae and bioclast preservation record tapholoss by rotting of non-calcified organisms (interpreted as fleshy algae) and by dissolution of aragonitic fossils. Carbonate loss by dissolution was counteracted and, locally, perhaps exceeded by carbonate precipitation of encrusting foraminifera and as oncoids. Sites of abrasion and carbonate dissolution (beach), sites with tapholoss by rotting and dissolution, but with microbialite/foraminiferal carbonate precipitation (lagoon, inner shelf), and sites only of carbonate precipitation (ooid shoals) co-existed on discrete shelf compartments. Compartmentalized, contemporaneous carbonate dissolution and precipitation, to total amounts yet difficult to quantify, impede straightforward estimates of ancient carbonate sediment budget. 相似文献
205.
Dr. Karl Krainer 《Facies》1995,33(1):195-214
Summary A heretofore undocumented example of skeletal mounds formed by the dasycladacean algaAnthracoporella spectabilis is described from mixed carbonate-clastic cycles (Auernig cyclothems) of the Late Carboniferous (Gzhelian) Auernig Group
of the central Carnic Alps in southern Austria.
The massive mound facies forms biostromal reef mounds that are up to several m thick and extend laterally over more than 100
m. The mound facies is developed in the middle of bedded limestones, which are up to 16 m thick. These limestones formed during
relative sea-level highstands when clastic influx was near zero.
The mound facies is characterized by well developed baffler and binder guilds and does not show any horizontal or vertical
zonation. Within the massive mound faciesAnthracoporella is frequently found in growth position forming bafflestones and wackestones composed of abundantAnthracoporella skeletons which toppled in situ or drifted slightly.Anthracoporella grew in such profusion that it dominated the available sea bottom living space, forming ‘algal meadows’ which acted as efficient
sediment producers and bafflers. BecauseAnthracoporella could not provide a substantial reef framework, and could not withstand high water turbulence, the biostromal skeletal mounds
accumulated in shallow, quiet water below the active wave base in water depths less than 30 m.
The massive mound facies is under- and overlain by, and laterally grades into bedded, fossiliferous limestones of the intermound
facies, composed mainly of different types of wackestones and packstones. Individual beds containAnthracoporella andArchaeolithophyllum missouriense in growth position, forming “micromounds’.
Two stages of mound formation are recognized: (1) the stabilization stage when bioclastic wackestones accumulated, and (2)
the skeletal mound stage when the sea-bottom was colonized byAnthracoporella and other members of the baffler and binder guilds, formingAnthracoporella bafflestones and wackestones of the mound facies.
A slight drop in sea-level led to the termination of the mound growth and accumulation of organic debris, particularly calcareous
algae, fusulinids, crinoids and bryozoans, forming well bedded limestones, which overlie the mound facies 相似文献
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The Pennsylvanian stratigraphic section of the Manzanita Mountains (central New Mexico, USA) is restudied at Cedro Peak. This Pennsylvanian succession is divided into the Sandia Formation, Gray Mesa Fm, Atrasado Fm, and lower part of Bursum Fm. The sampled limestones of the Gray Mesa and Atrasado formations yielded three age-distinctive fossil assemblages: they are of (a) latest Atokan/early Desmoinesian, (b) late early Desmoinesian, and (c) middle Virgilian. The following new taxa of foraminifers are proposed: Endoteboidea n. superfam.; Spireitlinidae n. fam.; Millerellinae n. subfam.; Pseudonovella marshalli n. sp.; Pseudonovella ohioicus nom. nov.; Pseudoacutella n. gen.; Pseudoacutella hoarei nom. nov.; Plectofusulina manzanensis n. sp. Translated or emended names are: Staffelloidea, Ozawainelloidea, Ozawainellidae, and Profusulinellidae. 相似文献
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