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61.
Hettinga K van Valenberg H de Vries S Boeren S van Hooijdonk T van Arendonk J Vervoort J 《PloS one》2011,6(4):e19433
Milk is the single source of nutrients for the newborn mammal. The composition of milk of different mammals has been adapted during evolution of the species to fulfill the needs of the offspring. Milk not only provides nutrients, but it also serves as a medium for transfer of host defense components to the offspring. The host defense proteins in the milk of different mammalian species are expected to reveal signatures of evolution. The aim of this study is therefore to study the difference in the host defense proteome of human and bovine milk. We analyzed human and bovine milk using a shot-gun proteomics approach focusing on host defense-related proteins. In total, 268 proteins in human milk and 269 proteins in bovine milk were identified. Of these, 44 from human milk and 51 from bovine milk are related to the host defense system. Of these proteins, 33 were found in both species but with significantly different quantities. High concentrations of proteins involved in the mucosal immune system, immunoglobulin A, CD14, lactoferrin, and lysozyme, were present in human milk. The human newborn is known to be deficient for at least two of these proteins (immunoglobulin A and CD14). On the other hand, antimicrobial proteins (5 cathelicidins and lactoperoxidase) were abundant in bovine milk. The high concentration of lactoperoxidase is probably linked to the high amount of thiocyanate in the plant-based diet of cows. This first detailed analysis of host defense proteins in human and bovine milk is an important step in understanding the function of milk in the development of the immune system of these two mammals. 相似文献
62.
Carrot arabinogalactan proteins are interlinked with pectins 总被引:4,自引:0,他引:4
Peter Immerzeel Mieke M. Eppink Sacco C. de Vries Henk A. Schols Alphons G. J. Voragen 《Physiologia plantarum》2006,128(1):18-28
Cell wall extracts from a carrot cell culture and tap roots were obtained by sequential extraction with water, EDTA buffer solution and cold sodium hydroxide solution. Arabinogalactan proteins (AGPs) were isolated from the extracts and from the medium of the cell culture and analysed for their molecular weight distribution and carbohydrate composition. Copper ions were used to separate the Yariv positive fractions into AGP fractions with a high and a low level of galacturonic acid (GalA). The GalA rich AGP fractions were incubated with pectin methylesterase and polygalacturonase. This enzyme incubation released GalA fragments from the AGP fractions as monitored by HPAEC and MALDI-TOF MS. At least part of carrot AGPs from the medium and cell walls may be covalently linked to pectin containing a homogalacturonan structural element. 相似文献
63.
64.
J A Keenan A G Sacco M G Subramanian M Kruger E C Yurewicz K S Moghissi 《Biology of reproduction》1991,44(1):150-156
Previous studies evaluating porcine zona pellucida antigens for immunocontraceptive purposes have in some cases revealed altered ovarian function in association with antibody response. This study was undertaken in an attempt to identify zona immunogens that do not cause adverse endocrine effects. To this end, we investigated the effects of highly purified preparations of native and deglycosylated pig zona pellucida antigens on ovarian function and immune response in the rabbit. Thirty female rabbits were immunized, 5 per group, with 100 micrograms each of either 1) SIZP, solubilized isolated zonae pellucidae; 2) ZP3, a purified porcine zona preparation containing the two principle glycoproteins, ZP3 alpha and ZP3 beta, endo-beta-galactosidase-digested ZP3 glycoproteins (approximately 30% deglycosylated) termed 3) ZP3 alpha/EBGD and 4) ZP3 beta/EBGD; and chemically deglycosylated ZP3 alpha and ZP3 beta (greater than or equal to 92% deglycosylated), termed 5) ZP3 alpha/DG and 6) ZP3 beta/DG. Rabbits injected with saline (n = 2) or Freund's adjuvant alone (n = 3) served as controls. Serum LH, FSH, estradiol, and progesterone were measured at 5-day intervals during seven 20-day cycles of hCG-induced pseudopregnancy over 42 wk. Anti-ZP3 titers, determined by RIA, developed in all treatment groups and correlated directly with carbohydrate content. Animals immunized with SIZP, ZP3, and ZP3 beta/EBGD showed a significant elevation of LH and FSH and a significant decline of peak progesterone levels by the fourth pseudopregnancy cycle. In contrast, animals immunized with ZP3 alpha/EBGD, ZP3 alpha/DG, and ZP3 beta/DG showed no significant elevations of gonadotropins and continued to display cyclic progesterone secretion in response to hCG.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
Peppermint (Mentha piperita L.) essential oil and its main components were assessed for their ability to interfere with plant plasma membrane potentials. Tests were conducted on root segments isolated from etiolated seedlings of cucumber (Cucumis sativus L.). Increasing the concentration of peppermint essential oil from 5 to 50 ppm caused a decrease in membrane potential (Vm) hyperpolarization of 10-3 mV, whereas concentrations from 100 up to 900 ppm caused an increasing depolarization of Vm (from 5 to 110 mV). When tested at 300 ppm, (+)-menthyl acetate, (-)-limonene and 1,8-cineole did not exert any significant effect on V(m), whereas (+)-menthofuran (73 mV), (+)-pulegone (85 mV), (+)-neomenthol (96 mV), (-)-menthol (105 mV) and (-)-menthone (111 mV) showed increased ability to depolarize V(m). A plot of log of octanol-water partition coefficient (K(ow)) against their depolarizing effect showed a significant negative correlation, suggesting that among all monoterpenoids increased membrane depolarization depends on lower K(ow). However, among monoterpene ketones, alcohols and furans, increased membrane depolarization is associated with a decline in water solubility. The possible effect of monoterpenoids on membrane ion fluxes is also discussed, since changes in the bioelectric potential of cells imply changes in the flux of ions across the plasma membrane 相似文献
66.
Effects of reproductive tissue-specific antisera on rabbit eggs 总被引:1,自引:0,他引:1
67.
Induction of Mn SOD in human monocytes without inflammatory cytokine production by a mutant endotoxin 总被引:4,自引:0,他引:4
Tian Licheng; White Julie E.; Lin Hung-Yun; Haran Visa S.; Sacco Joseph; Chikkappa G.; Davis Faith B.; Davis Paul J.; Tsan Min-Fu 《American journal of physiology. Cell physiology》1998,275(3):C740
Endotoxin selectively induces monocyte Mn superoxide dismutase(SOD) without affecting levels of Cu,Zn SOD, catalase, or glutathione peroxidase. However, little is known about the structure-activity relationship and the mechanism by which endotoxin induces Mn SOD. Inthis study we demonstrated that a mutant Escherichiacoli endotoxin lacking myristoyl fatty acid at the3' R-3-hydroxymyristate position of the lipid A moiety retained its full capacity to coagulate Limulus amoebocyte lysate comparedwith the wild-type E. coli endotoxinand markedly stimulated the activation of human monocyte nuclearfactor-B and the induction of Mn SOD mRNA and enzyme activity.However, in contrast to the wild-type endotoxin, it failed to inducesignificant production of tumor necrosis factor- and macrophageinflammatory protein-1 by monocytes and did not induce thephosphorylation and nuclear translocation of mitogen-activated proteinkinase. These results suggest that1) lipid A myristoyl fatty acid,although it is important for the induction of inflammatory cytokineproduction by human monocytes, is not necessary for the induction of MnSOD, 2) endotoxin-mediated inductionof Mn SOD and inflammatory cytokines are regulated, at least in part,through different signal transduction pathways, and3) failure of the mutant endotoxinto induce tumor necrosis factor- production is, at least in part,due to its inability to activate mitogen-activated protein kinase. 相似文献
68.
Antigens of the rabbit ovary, oviduct and uterus 总被引:1,自引:0,他引:1
69.
70.
Moderate alcohol consumption is associated with better endothelial function: a cross sectional study
Keiko Suzuki Mitchell SV Elkind Bernadette Boden-Albala Zhezhen Jin Grace Berry Marco R Di Tullio Ralph L Sacco Shunichi Homma 《BMC cardiovascular disorders》2009,9(1):1-5