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41.
Rabbit polyclonal antibody produced by a major royal jelly protein 1 (MRJP1) specific peptide reacted only with a MRJP1. Indirect ELISA with the antibody revealed a MRJP1 level of 4.12–4.67 g/100 g in different company's royal jelly, which almost agreed with that of a hexametric form of MRJP1 (apisin) measured by high performance liquid chromatography. These results suggest that MRJP1 exists mainly as apisin in royal jelly.  相似文献   
42.
Seeding cells and scaffolds play pivotal roles in bone tissue engineering and regenerative medicine.Wharton’s jelly-derived mesenchymal stem cells(WJCs)from human umbilical cord represent attractive and promising seeding cells in tissue regeneration and engineering for treatment applications.This study was carried out to explore the biocompatibility of scaffolds to seeding cells in vitro.Rod-like nano-hydroxyapatite(RN-HA)and flake-like micro-hydroxyapatite(FM-HA)coatings were prepared on Mg-Zn-Ca alloy substrates using micro-arc oxidation and electrochemical deposition.WJCs were utilized to investigate the cellular biocompatibility of Mg-Zn-Ca alloys after different surface modifications by observing the cell adhesion,morphology,proliferation,and osteoblastic differentiation.The in vitro results indicated that the RN-HA coating group was more suitable for cell proliferation and cell osteoblastic differentiation than the FM-HA group,demonstrating better biocompatibility.Our results suggested that the RN-HA coating on Mg-Zn-Ca alloy substrates might be of great potential in bone tissue engineering.  相似文献   
43.
蜜蜂王浆主蛋白(MRJPs)基因家族结构与功能概述   总被引:1,自引:0,他引:1  
《环境昆虫学报》2013,35(4):494-501
王浆主蛋白(Major royal jelly proteins,MRJPs)是王浆中的水溶性蛋白,为王浆蛋白的主要组分。因结构与功能的相似性,各王浆蛋白编码基因构成一个基因家族。目前该基因家族已鉴定出9个成员,依次命名为mrjp 1~9。该家族为单系群,拥有共同的祖先—yellow-e3,各成员之间具有较高的同源性。随着进化的进行,该家族逐步进化出营养及其它多种生物学功能。本文从该基因家族成员的鉴定、基因和蛋白质的结构特征、进化、功能以及其表达调控等多个方面进行综述,以期为相关的研究和应用提供帮助。  相似文献   
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45.
Activation state of sperm motility named “hyperactivation” enables mammalian sperm to progress through the oviductal matrix, although a similar state of sperm motility is unknown in non‐mammalian vertebrates at fertilization. Here, we found a high motility state of the sperm in the newt Cynops pyrrhogaster. It was predominantly caused in egg jelly extract (JE) and characterized by a high wave velocity of the undulating membrane (UM) that was significantly higher at the posterior midpiece. An insemination assay suggested that the high motility state might be needed for sperm to penetrate the egg jelly, which is the accumulated oviductal matrix. Specific characteristics of the high motility state were completely abrogated by a high concentration of verapamil, which blocks the L‐type and T‐type voltage‐dependent Ca2+ channels (VDCCs). Mibefradil, a dominant blocker of T‐type VDCCs, suppressed the wave of the UM at the posterior midpiece with separate wave propagation from both the anterior midpiece and the posterior principal piece. In addition, nitrendipine, a dominant L‐type VDCC blocker, weakened the wave of the UM, especially in the anterior midpiece. Live Ca2+ imaging showed that, compared with the intact sperm in the JE, the relative intracellular Ca2+ level changed especially in the anterior and posterior ends of the midpiece of the blocker‐treated sperm. These suggest that different types of Ca2+ channels mediate the intracellular Ca2+ level predominantly in the anterior and posterior ends of the midpiece to maintain the high motility state of the newt sperm.  相似文献   
46.
Background: For quantitative evaluation of masticatory ability of the elderly patients, there should be a simple and reliable method without special techniques and instruments. Objective: The purpose of this study was to examine the validity and reliability of a visual scoring method for assessing masticatory performance. Materials and Methods: A 10‐stage scale for visually scoring was rated based on the range of the glucose concentration dissolved from comminuted jelly. Photographic images of comminuted jellies were produced as a standard material for each score. Fifty subjects were recruited as raters who graded the visual score for 50 photographic images of comminuted jellies on the screen of a lap‐top three times in random order. Results: There were strong correlations (rs = 0.911– 0.981, Spearman’s rank coefficient) between the actual scores determined from the glucose concentration and the visual scores graded by subjects in all three measurements. The intraclass correlation coefficients (ICCs) of the inter‐rater reliability and the ICCs of the intra‐rater reliability of the visual scoring ranged from 0.946 to 0.947 and from 0.860 to 0.987 in three measurements, respectively. Conclusions: These results indicated that the visual scoring method was valid and reliable for evaluation of masticatory performance.  相似文献   
47.
The structures of N-glycans of total glycoproteins in royal jelly have been explored to clarify whether antigenic N-glycans occur in the famous health food. The structural feature of N-glycans linked to glycoproteins in royal jelly was first characterized by immunoblotting with an antiserum against plant complex type N-glycan and lectin-blotting with Con A and WGA. For the detail structural analysis of such N-glycans, the pyridylaminated (PA-) N-glycans were prepared from hydrazinolysates of total glycoproteins in royal jelly and each PA-sugar chain was purified by reverse-phase HPLC and size-fractionation HPLC. Each structure of the PA-sugar chains purified was identified by the combination of two-dimensional PA-sugar chain mapping, ESI-MS and MS/MS analyses, sequential exoglycosidase digestions, and 500 MHz 1H-NMR spectrometry.

The immunoblotting and lectinblotting analyses preliminarily suggested the absence of antigenic N-glycan bearing β1-2 xylosyl and/or α1-3 fucosyl residue(s) and occurrence of β1-4GlcNAc residue in the insect glycoproteins.

The detailed structural analysis of N-glycans of total royal jelly glycoproteins revealed that the antigenic N-glycans do not occur but the typical high mannose-type structure (Man9~4GlcNAc2) occupies 71.6% of total N-glycan, biantennary-type structures (GlcNAc2Man3GlcNAc2) 8.4%, and hybrid type structure (GlcNAc1Man4GlcNAc2) 3.0%. Although the complete structures of the remaining 17% N-glycans; C4, (HexNAc3Hex3HexNAc2: 3.0%), D2 (HexNAc2Hex5HexNAc2: 4.5%), and D3 (HexNAc3Hex4HexNAc2: 9.5%) are still obscure so far, ESI-MS analysis, exoglycosidase digestions by two kinds of β-N-acetylglucosaminidase, and WGA blotting suggested that these N-glycans might bear a β1-4 linkage N-acetylglucosaminyl residue.  相似文献   
48.
The molecular characteristics of polysaccharide obtained by extracting with water from jelly fig (Ficus awkeotsang Makino) seeds were elucidated by measuring the weight-average molecular weight (Mw) and radius of gyration (RG), indicating the molecular expanse, by the light-scattering method.

The Mw and RG values of the water-soluble jelly fig polysaccharide were 84–130 × 104 and 240–450 mm, respectively, these values being larger than those of commercial LM pectin and HM pectin. In addition, the Mw and RG values of the water-soluble jelly fig polysaccharide initially increased after being extracted, indicating the highest values 5 hours after the extraction, and thereafter decreased. These changes in the time-course of the molecule reflected well the changes with time in the mechanical characteristics and network structure of the water-soluble jelly fig polysaccharide gel. Exponent α in the expression was found to be 0.37. From these results, the conformation of the water-soluble jelly fig polysaccharide molecule after association by the contained inorganic elements proved to be of globular form rather than a random coil shape as a result of contraction of the molecule.  相似文献   
49.
Osmophilic Aspergillus responsible for spoilage of rice, corn, milo and wheat have been isolated and identified. Fifteen strains were classified as members of the Aspergillus glaucus group, and were subdivided into A. ruber, A. repens, A. mangini, A. chevalieri and A. montevidensis. Nine strains were classified as members of the A. restrictus group, and were subdivided into A. gracilis, A. vitricolae and A. casiellus. The other 7 strains were classified as A. versicolor in the A. versicolor group, A. sulphureus in the A. ochraceus group, and A. niveus in the A. flavipes group.

All of dose-survival curves obtained with the conidia of 10 strains showed the sigmoidal type having the D10 values between 18 and 30 krad. The survival curves obtained with the ascospores of A. glaucus group also showed the sigmoidal type having the D10 values of 54 krad. Radio-sensitivity of the dry conidia was similar to that of the dry ascospores, having D10 values between 50 to 58 krad.  相似文献   
50.
《Journal of Asia》2022,25(3):101964
Honeybee venom is a complex mixture of toxic components, including major royal jelly protein (MRJP) 8 and 9. MRJP 8 and MRJP 9 are allergens, and MRJP 8 reduces melittin-induced cell apoptosis. However, their functional roles are poorly understood, and their antimicrobial activities have not been determined. In this study, the antimicrobial role of MRJP 8 and MRJP 9 of honeybee (Apis mellifera) venom (AmMRJP 8 and AmMRJP 9) was demonstrated. The presence of AmMRJP 8 and AmMRJP 9 in the secreted venom was observed using antibodies against recombinant AmMRJP 8 and AmMRJP 9 produced in baculovirus-infected insect cells. Recombinant AmMRJP 8 and AmMRJP 9 exhibited an inhibitory activity against microbial serine proteases. Consistent with their inhibitory activity, they induced structural damage by binding to microbial surfaces, resulting in a broad-spectrum antimicrobial activity against bacteria and fungi. They had little effect on hemolysis. Therefore, AmMRJP 8 and AmMRJP 9 could function as antimicrobial agents in honeybee venom.  相似文献   
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