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Ferreira Jéssica Cristina Barbosa de Araújo Silva-Cardoso Inaê Mariê Meira Rennan Oliveira da Silva Costa Frederico Henrique Scherwinski-Pereira Jonny Everson 《In vitro cellular & developmental biology. Plant》2022,58(5):750-768
In Vitro Cellular & Developmental Biology - Plant - An efficient, reproducible, and unprecedented protocol of somatic embryogenesis (SE) was developed from leaf tissues of adult plants of... 相似文献
113.
Low sodium isocyanurate concentrations as a substitute to medium autoclaving in plant tissue culture
da Costa Urtiga Caio de Araújo Silva-Cardoso Inaê Mariê Araujo Figueiredo Sergio 《Plant Cell, Tissue and Organ Culture》2019,139(3):601-604
Plant Cell, Tissue and Organ Culture (PCTOC) - An optimization for a medium sterilization method, capable of substituting autoclaving, was developed using low concentrations of sodium isocyanurate... 相似文献
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Andrew E Rosselot Miri Park Mari Kim Toru MatsuUra Gang Wu Danilo E Flores Krithika R Subramanian Suengwon Lee Nambirajan Sundaram Taylor R Broda Heather A McCauley Jennifer A Hawkins Kashish Chetal Nathan Salomonis Noah F Shroyer Michael A Helmrath James M Wells John B Hogenesch Sean R Moore Christian I Hong 《The EMBO journal》2022,41(2)
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No Patrick MBondoukw Reinne Moutongo Komi Gbdand Jacques Mari Ndong Ngomo Tatiana Hountohotegb Rafiou Adamou Jeanne Vanessa Koumba Lengongo Kowir Pambou Bello Denise Patricia Mawili-Mboumba Adrian John Frederick Luty Marielle Karine Bouyou-Akotet 《PLoS neglected tropical diseases》2022,16(4)
Malaria, blood-borne filarial worms and intestinal parasites are all endemic in Gabon. This geographical co-distribution leads to polyparasitism and, consequently, the possibility of immune-mediated interactions among different parasite species. Intestinal protozoa and helminths could modulate antimalarial immunity, for example, thereby potentially increasing or reducing susceptibility to malaria. The aim of the study was to compare the cytokine levels and cytokine ratios according to parasitic profiles of the population to determine the potential role of co-endemic parasites in the malaria susceptibility of populations. Blood and stool samples were collected during cross-sectional surveys in five provinces of Gabon. Parasitological diagnosis was performed to detect plasmodial parasites, Loa loa, Mansonella perstans, intestinal helminths (STHs) and protozoan parasites. Nested PCR was used to detect submicroscopic plasmodial infection in individuals with negative blood smears. A cytometric bead array was used to quantify interleukin (IL)-6, IL-10 and tumour necrosis factor (TNF)-α in the plasma of subjects with different parasitological profiles. Median IL-6 and IL-10 levels and the median IL-10/TNF-α ratio were all significantly higher among individuals with Plasmodium (P.) falciparum infection than among other participants (p<0.0001). The median TNF-α level and IL-10/IL-6 ratio were higher in subjects with STHs (p = 0.09) and P. falciparum-intestinal protozoa co-infection (p = 0.04), respectively. IL-6 (r = -0.37; P<0.01) and IL-10 (r = -0.37; P<0.01) levels and the IL-10/TNF-α ratio (r = -0.36; P<0.01) correlated negatively with age. Among children under five years old, the IL-10/TNF-α and IL-10/IL-6 ratios were higher in those with intestinal protozoan infections than in uninfected children. The IL-10/TNF-α ratio was also higher in children aged 5–15 years and in adults harbouring blood-borne filariae than in their control counterparts, whereas the IL-10/IL-6 ratio was lower in those aged 5–15 years with filariae and intestinal parasites but higher in adults with intestinal parasitic infections. Asymptomatic malaria is associated with a strong polarization towards a regulatory immune response, presenting high circulating levels of IL-10. P. falciparum/intestinal protozoa co-infections were associated with an enhanced IL-10 response. Immunity against malaria could differ according to age and carriage of other parasites. Helminths and intestinal protozoa can play a role in the high susceptibility to malaria currently observed in some areas of Gabon, but further investigations are necessary. 相似文献
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Capture of human Fab fragments by expanded bed adsorption with a mixed mode adsorbent 总被引:1,自引:0,他引:1
A novel group of mixed mode adsorbents has been developed for purification of monoclonal and polyclonal antibodies from a broad range of raw materials such as hybridoma cell culture, ascites fluid, animal sera, milk, whey and egg yolk. The aim of this study was to determine whether such mixed mode adsorbents were also useful for the recovery of recombinant proteins from microbial feedstocks. This paper describes the performance of one of these adsorbents for expanded bed capture of a human Fab fragment from recombinant E. Coli cell extracts.It is concluded that the mixed mode adsorbent binds the Fab fragment efficiently from crude extracts without any requirement for preconditioning the extract by for example de-salting or dilution. The capacity of the mixed mode adsorbent is approx. 12 mg Fab/ml matrix.The novel mixed mode adsorbent can be useful during production of highly purified Fab fragments as the first step in a purification scheme. In this respect the mixed mode adsorbent is advantageous over alternative commercially available ion-exchange materials which require pre-conditioning of cell extract for Fab' capture. Together with the concentration and clarification effect a significant enrichment of the Fab fragment is obtained in one single high yield operation. 相似文献
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The actomyosin motor as a principal functional component of cell motility is highly coordinated in regulating the participating molecular components. At the same time, it has to be flexible and plastic enough to accommodate itself to a wide variety of operational conditions. We prepared two different types of actomyosin systems. One is a natural intact actomyosin system with no artificial constraint on the kinetic degrees of freedom of the actin filaments, and the other is a regulated one with actin filaments supplemented by intra- and intermolecular crosslinking to suppress the kinetic degrees of freedom to a certain extent. Crosslinked actomyosin systems were found to remain almost insensitive to calcium regulation even when intact troponin-tropomyosin regulatory component was incorporated. Both the ATPase and the motile activities of the actin filaments sliding on myosin molecules were markedly lowered by the crosslinking. In contrast, once the crosslinking was cleaved, both properties returned to the normal as with intact actomyosin systems. 相似文献
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