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111.
Adhityo Wicaksono Sofi Mursidawati Lazarus A. Sukamto Jaime A. Teixeira da Silva 《Planta》2016,244(2):289-296
Main Conclusion
The propagation of Rafflesia spp. is considered to be important for future development of ornamental and other applications. Thus far, the only successful propagation technique has been grafting. This mini-review succinctly emphasizes what is known about Rafflesia species.Members of the genus Rafflesia (Rafflesiaceae), which are holoparasitic plants known to grow on a host vine, Tetrastigma sp., are widely spread from the Malayan Peninsula to various islands throughout Indonesia. The plant’s geographical distribution as well as many other aspects pertaining to the basic biology of this genus have still not been studied. The young flower buds and flowers of wild Rafflesia hasseltii Suringar, Rafflesia keithii Meijer and Rafflesia cantleyi Solms-Laubach are used in local (Malaysia and Indonesia) traditional ethnomedicine as wound-healing agents, but currently no formal published research exists to validate this property. To maintain a balance between its ethnomedicinal and ornamental use, and conservation, Rafflesia spp. must be artificially cultivated to prevent overexploitation. A successful method of vegetative propagation is by host grafting using Rafflesia-impregnated Tetrastigma onto the stem of a normal Tetrastigma plant. Due to difficulties with culture contamination in vitro, callus induction was only accomplished in 2010 for the first time when picloram and 2,4-D were added to a basal Murashige and Skoog medium, and the tissue culture of holoparasitic plants continues to be extremely difficult. Seeds harvested from fertile fruit may serve as a possible method to propagate Rafflesia spp. This paper provides a brief synthesis on what is known about research related to Rafflesia spp. The objective is to further stimulate researchers to examine, through rigorous scientific discovery, the mechanisms underlying the ethnomedicinal properties, the flowering mechanisms, and suitable in vitro regeneration protocols that would allow for the fortification of germplasm conservation.112.
Regulators of complement activity mediate inhibitory mechanisms through a common C3b‐binding mode
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Federico Forneris Jin Wu Xiaoguang Xue Daniel Ricklin Zhuoer Lin Georgia Sfyroera Apostolia Tzekou Elena Volokhina Joke CM Granneman Richard Hauhart Paula Bertram M Kathryn Liszewski John P Atkinson John D Lambris Piet Gros 《The EMBO journal》2016,35(10):1133-1149
Regulators of complement activation (RCA) inhibit complement‐induced immune responses on healthy host tissues. We present crystal structures of human RCA (MCP, DAF, and CR1) and a smallpox virus homolog (SPICE) bound to complement component C3b. Our structural data reveal that up to four consecutive homologous CCP domains (i–iv), responsible for inhibition, bind in the same orientation and extended arrangement at a shared binding platform on C3b. Large sequence variations in CCP domains explain the diverse C3b‐binding patterns, with limited or no contribution of some individual domains, while all regulators show extensive contacts with C3b for the domains at the third site. A variation of ~100° rotation around the longitudinal axis is observed for domains binding at the fourth site on C3b, without affecting the overall binding mode. The data suggest a common evolutionary origin for both inhibitory mechanisms, called decay acceleration and cofactor activity, with variable C3b binding through domains at sites ii, iii, and iv, and provide a framework for understanding RCA disease‐related mutations and immune evasion. 相似文献
113.
114.
Rajeka Lazarus Sarah Kelly Matthew D. Snape Corinne Vandermeulen Merryn Voysey Karel Hoppenbrouwers Annick Hens Pierre Van Damme Stephanie Pepin Isabel Leroux-Roels Geert Leroux-Roels Andrew J. Pollard 《PloS one》2016,11(11)
Avian influenza continues to circulate and remains a global health threat not least because of the associated high mortality. In this study antibody persistence, booster vaccine response and cross-clade immune response between two influenza A(H5N1) vaccines were compared. Participants aged over 18-years who had previously been immunized with a clade 1, A/Vietnam vaccine were re-immunized at 6-months with 7.5 μg of the homologous strain or at 22-months with a clade 2, alum-adjuvanted, A/Indonesia vaccine. Blood sampled at 6, 15 and 22-months after the primary course was used to assess antibody persistence. Antibody concentrations 6-months after primary immunisation with either A/Vietnam vaccine 30 μg alum-adjuvanted vaccine or 7.5 μg dose vaccine were lower than 21-days after the primary course and waned further with time. Re-immunization with the clade 2, 30 μg alum-adjuvanted vaccine confirmed cross-clade reactogenicity. Antibody cross-reactivity between A(H5N1) clades suggests that in principle a prime-boost vaccination strategy may provide both early protection at the start of a pandemic and improved antibody responses to specific vaccination once available.Trial Registration: ClinicalTrials.gov NCT00415129相似文献
115.
116.
CM Ward AP Wilkinson S Bramham HA Lee HW-S Chan GW Butcher A Hutchings MRA Morgan 《Mycotoxin Research》1990,6(2):73-83
From a single aflatoxin B1 oxime — bovine serum albumin conjugate, polyclonal and monoclonal antibody preparations were produced. The four rabbit polyclonal antisera were specific for aflatoxin Bi in a microtitration plate enzyme — linked immunosorbent assay. The monoclonal antibodies showed a wide range of differing specificities, recognizing, for example, aflatoxins B1, B2, G1 and G2; B1 and B2; B1 and G1; and G1 alone. No antibody preparations reacted with aflatoxin M1. The significance of these results to the strategy of anti-aflatoxin antibody production for use in quantitative enzyme immunoassays is discussed. 相似文献
117.
Human skin chymotryptic proteinase. Isolation and relation to cathepsin g and rat mast cell proteinase I 总被引:11,自引:0,他引:11
N M Schechter J E Fr?ki J C Geesin G S Lazarus 《The Journal of biological chemistry》1983,258(5):2973-2978
A chymotrypsin-like proteinase was purified 2400-fold from human skin. The procedure involves extraction of the proteinase from skin in 2 M KCl, precipitation with protamine chloride, fractionation by gel filtration chromatography, and fractionation by chromatography using a CH-Sepharose-D-tryptophan methyl ester affinity column. The properties of this proteinase were compared to the rat mast cell proteinase I and human cathepsin G. Differences were observed in the rates at which the proteinases were inhibited by diisopropyl fluorophosphate, the sensitivity of the proteinases to protein proteolytic inhibitors, the relative hydrolytic rates of the proteinases for a series of substrates, and the kinetic constants of the proteinases for synthetic substrates. The human skin proteinase did not react with antiserum to the rat skin proteinase and did not elute in the same position as the rat skin proteinase on gel filtration columns. These data demonstrate that the human skin proteinase is distinct from the other proteinases. Extracts of involved skin from patients with cutaneous mastocytosis had 15-fold higher levels of chymotryptic activity than extracts of uninvolved skin or skin from normal controls. The enzymatic properties of the material extracted from the biopsied skin were similar to those of the proteinase from normal skin, suggesting that the human skin chymotrypsin-like proteinase is a mast cell constituent. 相似文献
118.
119.
Monocyte procollagenase and tissue inhibitor of metalloproteinases. Identification, characterization, and regulation of secretion 总被引:5,自引:0,他引:5
E J Campbell J D Cury C J Lazarus H G Welgus 《The Journal of biological chemistry》1987,262(33):15862-15868
Alveolar macrophages have been shown to secrete a procollagenase and the tissue inhibitor of metalloproteinases (TIMP), which are similar or identical to the corresponding proteins of human skin fibroblasts. Little is known, however, about the collagenolytic activity of normal human monocytes. We have applied immunologic, biochemical, and molecular biologic tools to examine the collagenolytic profile of freshly isolated peripheral blood monocytes. Our studies indicate that: 1) monocytes are capable of producing both procollagenase and TIMP that are identical to the corresponding products of skin fibroblasts, alveolar macrophages, and U-937 cells; 2) unstimulated monocytes in vitro secrete high levels of TIMP, but little or no procollagenase; 3) an as yet unidentified component(s) of serum are required for in vitro production of TIMP (but not procollagenase) by monocytes; 4) even when stimulated, monocytes secrete much smaller quantities of procollagenase in comparison with macrophages; and 5) regulation of the secretion of procollagenase and TIMP by monocytes exhibits a high degree of individual variability, but is nevertheless subject to clearly different control mechanisms than our previous findings would indicate for alveolar macrophages. Monocytes thus express a macrophage-like, rather than a neutrophil-like, profile of proteins capable of mediating collagen turnover, the regulation of which is distinct from that of more differentiated alveolar macrophages. Further study of monocyte and macrophage collagenolytic activities may provide insights into both the cell biology of mononuclear phagocyte maturation and the mechanisms by which such cells mediate the turnover of interstitial collagens. 相似文献
120.
K J Lazarus G A Hashim V A Varitek P Y Paterson E D Day 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(1):275-281
Synthetic peptide S24 (TTHYGSLPQKG) represents residues 65-74 of myelin basic protein (MBP) and contains the major determinant involved in the development of experimental allergic encephalomyelitis (EAE) in rabbits. This peptide is completely conserved in all nonprimate mammals for which sequence information is available. Although it is clear that peptides containing the S24 region are capable of inducing EAE, previous serologic studies have resulted in the conclusion that the determinant is "buried" or sequestered in intact MBP. Employing a liquid phase radioimmunoassay, we studied Ab responses to the S24 determinant in six rabbits injected with rat myelin. Two of the six animals developed small but measurable responses to the S24 determinant. In one of these rabbits, the response was boosted with a covalent conjugate of S82 and methylated BSA (MBSA). We also measured antibodies to the S24 determinant in rabbit antisera to human, monkey, dog, bovine, and the large and small forms of rat MBP. By nonequilibrium inhibition analysis, we determined that the antibody responses to these antigens were all directed to a determinant composed of residues 66-71 of MBP, and that intact MBP inhibits the binding of these antibodies to radiolabeled S24. The results demonstrate that the rabbit encephalitogenic region of myelin basic protein is exposed in the intact molecule both as an immunogen and as a reactant in liquid-phase assays; furthermore, they demonstrate that MBP antigenicity leading to B cell responses does not necessarily depend on sequence differences between the injected protein and its counterpart in the host species. The latter finding reinforces the contention of Atassi that autoantibody responses are not exclusive to "evolutionary hypervariable locations." 相似文献