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1.
Nanoparticles are increasingly used to adjuvant vaccine formulations due to their biocompatibility, ease of manufacture and the opportunity to tailor their size, shape, and physicochemical properties. The efficacy of similarly-sized silica (Si-OH), poly (D,L-lactic-co-glycolic acid) (PLGA) and poly caprolactone (PCL) nanoparticles (nps) to adjuvant recombinant capsomere presenting antigenic M2e modular peptide from Influenza A virus (CapM2e) was investigated in vivo. Formulation of CapM2e with Si-OH or PLGA nps significantly boosted the immunogenicity of modular capsomeres, even though CapM2e was not actively attached to the nanoparticles prior to injection (i.e., formulation was by simple mixing). In contrast, PCL nps showed no significant adjuvant effect using this simple-mixing approach. The immune response induced by CapM2e alone or formulated with nps was antibody-biased with very high antigen-specific antibody titer and less than 20 cells per million splenocytes secreting interferon gamma. Modification of silica nanoparticle surface properties through amine functionalization and pegylation did not lead to significant changes in immune response. This study confirms that simple mixing-based formulation can lead to effective adjuvanting of antigenic protein, though with antibody titer dependent on nanoparticle physicochemical properties.  相似文献   
2.
In the Ecuadorian coast one of the most destructive diseases of the pachaco is vascular wilt or stem rot caused by Ceratocystis complex, so the aim of this study was to determine the factors that affect the efficiency of the reaction of bark pachaco to this disease. This research was conducted under laboratory conditions, using trees pachaco S38, S41, S98, AE-1, AE-2 and AE-3, and pathogenic species Ceratocystis paradoxa and C. moniliformis. The method utilized was tissue stem bark,with bark sections with 4.5 cm2, and a suspension of 3x104 units infection and remained in a humid chamber for 96 hours at 25 ± 5 °C. Were determined grades of resistance/ susceptibility using a scale from 0 to 4, depending on the amount of mycelia and peritecio in each plant sample. Three factors were used: four colonies obtained by several transfers from each fungal specie, four ages of colonies of each fungal specie and four volumes of inoculum applied (units of infection), using for each experiment separately Completely Randomized Design with 4 replications factorial arrangement. For comparison between treatment means was used Tukey test at 5% probability of error. For future trials using this technique, you could use 30-day colonies for C. paradoxa and 40 days for C. moniliformis, and an application volume of 100 μL/cm2, it would improve the level of response for the formation of perithecium and mycelia in samples cortex.  相似文献   
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Although Ensifera is a major insect model group, its phylogenetic relationships have been understudied so far. Few phylogenetic hypotheses have been proposed, either with morphological or molecular data. The largest dataset ever used for phylogeny reconstruction on this group is molecular (16S rRNA, 18S rRNA and 28S rRNA sequences for 51 ensiferan species), which has been used twice with different resultant topologies. However, only one of these hypotheses has been adopted commonly as a reference classification. Here we re‐analyse this molecular dataset with different methods and parameters to test the robustness and the stability of the adopted phylogeny. Our study reveals the instability of phylogenetic relationships derived from this dataset, especially for the deepest nodes of the group, and suggests some guidelines for future studies. The comparison between the different classifications proposed in the past 70 years for Ensifera and our results allows the identification of potential monophyletic clades (katydids, mole crickets, scaly crickets + Malgasia, true crickets, leaf roller crickets, cave crickets) and the remaining unresolved clades (wetas, Jerusalem crickets and most of the highest rank clades) in Ensifera phylogeny.  相似文献   
4.
Ridwansyah  Iwan  Yulianti  Meti  Apip  Onodera  Shin-ichi  Shimizu  Yuta  Wibowo  Hendro  Fakhrudin  M. 《Limnology》2020,21(3):487-498
Limnology - The Cimanuk River with a total watershed area of 4010.8 km2 flowing from the Garut Regency to Indramayu Delta is the longest in West Java Province. However, the cumulative...  相似文献   
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Exposure to environmental factors during fetal life and infancy is thought to play an important role in the early development of innate and adaptive immunity. The immunological relationship between mother and infant and the effect that environmental exposures have during pregnancy and early childhood have not been studied extensively. Here the production of cytokines was measured in 146 pairs of mothers and their 2- month-old infants. The effect of place of residence, socio-economic variables, parasitic infections as well as maternal and child characteristics on measured cytokine production was determined. Mothers producing high levels of IL-10, IFN-γ and IL-5 were more likely to have infants who also produced high levels of these cytokines either spontaneously (OR 2.6(95%CI 1.2–5.4), OR 2.9(CI 1.3–6.6), OR 11.2(CI 4.6–27.2), respectively) or in response to PHA (IL-10: OR 3.0(CI 1.4–6.6), IFN-γ: OR 2.0(CI 1.0–4.2), respectively) even after adjustment for potential confounding variables. This was not the case for TNF-α. In response to LPS, place of residence was a strong determinant of infant IL-10 (OR 0.2(CI 0.1–0.9)) and TNF-α (OR 0.3(CI 0.1–0.9)) production. Maternal protozoan infections was independently associated with reduced infant IL10 in response to PHA and to LPS as well as reduced TNF-α and IFN-γ in response to PHA. These results indicate strong relationship between maternal and infant''s cellular immune responses even after taking into account many environmental influences that could affect infant''s response directly or indirectly through uterine microenvironment. However, place of residence and intestinal infections may still directly affect the immune responses of the infant. Taken together, the study provides evidence for imprinted cytokine responses of an infant which may have implications for their reaction to incoming antigens, warranting further investigation into the role that genetics or epigenetics play in shaping the cytokine response by an infant to self or external antigens.  相似文献   
7.
Abstract

CpG methylation determines a variety of biological functions of DNA. The methylation signal is interpreted by proteins containing a methyl-CpG binding domain (MBDs). Based on the NMR structure of MBD1 complexed with methylated DNA we analysed the recognition mode by means of molecular dynamics simulations.

As the protein is monomeric and recognizes a symmetrically methylated CpG step, the recognition mode is an asymmetric one. We find that the two methyl groups do not contribute equally to the binding energy. One methyl group is associated with the major part of the binding energy and the other one nearly does not contribute at all. The contribution of the two cytosine methyl groups to binding energy is calculated to be ?3.6 kcal/mol. This implies a contribution of greater than two orders of magnitude to the binding constant. The conserved amino acid Asp32 is known to be essential for DNA binding by MBD1, but so far no direct contact with DNA has been observed. We detected a direct DNA base contact to Asp32. This could be the main reason for the importance of this amino acid. MBD contacts DNA exclusively in the major groove, the minor groove is reserved for histone contacts. We found a deformation of the minor groove shape due to complexation by MBD1, which indicates an information transfer between the major and the minor groove.  相似文献   
8.
Ichthyological Research - Phenacoscorpius longicaudalis sp. nov. is described from 19 specimens collected in depths of 228–990 m off Western Australia, eastern Indian Ocean. The new...  相似文献   
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Previous research has shown that soluble protein recovery by chitosan (Chi) complexes with polyanions such as alginate (Alg) is more effective than using chitosan alone. In this study, Chi-Alg complexes were used to recover soluble proteins from surimi wash water (SWW) slightly acidified to pH 6. Six Chi samples differing in molecular weight (MW) and degree of deacetylation (DD) were used at 20, 40 and 100mg/L SWW Chi-Alg complexes prepared with a Chi:Alg mixing ratio previously optimized (MR=0.2). FTIR analysis of the solids recovered revealed the three characteristic amide bands observed in the same region for untreated SWW confirming protein adsorption by Chi-Alg. The superior effectiveness of Chi complexes was confirmed but differences among chitosan types could not be correlated to MW and DD. Experimental Chi samples with 94%, 93%, 75% and 93% DD and 22, 47, 225 and 3404 x 10(3)Da, respectively, showed 73-76% protein adsorption while a commercial chitosan sample with 84% DD and 3832 x 10(3)Da had 74-83% protein adsorption. An experimental chitosan, SY-1000 with 94% DD and 1.5 x 10(6)Da, showed the highest protein adsorption (79-86%) and turbidity reduction (85-92%) when used at 20mg/L SWW.  相似文献   
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