A novel calcium supplement prepared by phytoferritin nanocages protects against absorption inhibitors through a unique pathway

The consumption of milk is declining in industrialized countries, leading to inadequate calcium intake. Therefore, it is important to explore a new class of Ca-enriched nutrient for the fortification of food. In this work, we prepared a novel class of soluble and edible Ca–protein complexes where approximately 140 calcium ions were encapsulated within a phytoferritin nanocage. As an alternative to other organic and/or inorganic carriers, protein nanocages were found to provide a unique vehicle of biological origin for the intracellular delivery of calcium ions for supplementation. Such encapsulation can protect calcium ions within protein cages against dietary factors such as tannic acid (TA), oxalic acid (OA), and other divalent metal ions in foodstuffs. We demonstrated that the calcium-containing ferritin composites can be absorbed by Caco-2 cells through a process where a TfR1 receptor is involved, whereas the uptake of free calcium ions has been known to be associated with another receptor, DMT1, indicating that the calcium ions encapsulated in supramolecular protein cages can be internalized by the Caco-2 cells through a different pathway from its free analogs for calcium supplementation.     

上海市浦东新区院前急救资源配置存在问题与对策

目的:分析浦东新区院前急救资源配置中存在的问题并提出对策。方法:利用浦东新区医疗急救中心数据库中2008年至2009年有关数据资料,参照卫生部、上海市有关标准,通过客观的指标进行分析。结果:浦东新区救护车辆的配置为0.11辆/万人口。共需200名急救医师,2008年和2009年实际急救医师配置人数为50名和67名。非急救任务比例约占36.7%。院前急救回车率达5.6%。年空车次数为3 221次。病种排序前5位依次为创伤、神经系统、呼吸系统、心血管系统、消化系统疾病。院前急救平均反应时间为(10.8±3.7)min。结论:浦东新区急救资源配置不足,无法满足大众的实际需求。急救资源的利用存在不足之处。建议在争取基本配置达标的同时,还要加强人力资源建设,同时规范各项管理制度,科学合理地配置急救资源。     

Development and applications of universal H7 subtype-specific antibodies for the analysis of influenza H7N9 vaccines

H7N9 is a newly emerged avian influenza virus with a relatively high mortality rate in humans. At this time, there is no licensed vaccine for human protection. Development of analytical tools for H7N9 vaccine could facilitate vaccine development. Here, a universally conserved epitope in all H7 hemagglutinin (HA) sequences was identified through comprehensive bioinformatics analyses. The peptide epitope, RSGSSFYAEMK, (aa positions 149 to 159), is located on the head of the HA molecule. Antibodies generated against this universal H7 epitope were remarkably specific against H7 viral sequence with no detectable cross-reactivity to other HA subtypes. A new immunoblotting assay based on the universal H7 antibody was developed and compared with the traditional single radial immunodiffusion assay (SRID) for potency analyses of candidate H7N9 vaccines. This new assay was more sensitive and rapid compared to SRID. In addition to statistically acceptable precision and reproducibility, the new assay differs from many other alternative potency assays for influenza vaccine in that it is potentially stability-indicating, which is an important requirement for industry vaccine stability studies analyses. Furthermore, the robustness of this new assay was demonstrated by the quantitative determination of HA content in four H7N9 vaccines (split or inactivated) from different manufacturers.     

Genetic Variation in GSTM1 Is Associated With Susceptibility to Noise-Induced Hearing Loss in a Chinese Population

OBJECTIVES:: To investigate whether glutathione S-transferases (GST) genetic polymorphisms (GSTT1 rs1049055, GSTM1 rs10712361, and GSTP1 rs1695) are associated with susceptibility to noise-induced hearing loss (NIHL). METHODS:: These polymorphisms were analyzed in 444 NIHL and 445 normal hearing workers. In addition, total plasma GST activity was measured in all subjects. RESULTS:: Individuals with the GSTM1 null genotype had a statistically significantly increased risk of NIHL (odds ratio [OR] = 1.64, 95% confidence interval [CI] = 1.26 to 2.13) compared with those carrying a wild-type GSTM1 genotype. This effect was more pronounced among the workers exposed to 86 to 91 dB(A) (OR = 3.35, 95% CI = 1.54 to 7.31). Glutathione S-transferase activity of the NIHL workers was also lower than that of normal hearing workers (14.5 ± 5.1 U/ml vs 15.9 ± 6.3 U/ml, P = 0.010). CONCLUSION:: Our results suggest that GSTM1 polymorphism is associated with susceptibility to NIHL.     

Inhibitory effects of PPAR-γ on endothelin-1-induced inflammatory pathways in vascular smooth muscle cells from normotensive and hypertensive rats

The present study evaluated the effects of endothelin (ET)-1 and the peroxisome proliferator activated receptor γ (PPAR-γ) agonist, rosiglitazone, on inflammatory markers in vascular smooth muscle cells (VSMCs) from normotensive (WKY) and hypertensive (SHRSP) rats. Rat VSMC-derived mesenteric arteries from WKY and SHRSP were treated with ET-1 (100 mmol/L) and rosiglitazone (1μmol/L) or ET type A (ET_A) or type B (ET_B) receptor antagonists. Nuclear factor kappa-B (NFκB) binding activity was assessed by electrophoretic mobility shift assay and phospho-inhibitory κB (IκB); vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1, and cyclooxygenase (COX)-2 expression was determined using Western blotting. ET-1 significantly increased NFκB binding, and VCAM-1, ICAM, and COX-2 expression to a greater degree in SHRSP than in WKY VSMC. These changes were associated with increased phosphorylation of IκB, thus resulting in decreased NFκB inhibition. Co-incubation with PPAR-γ activator rosiglitazone, or ET_A or ET_B receptor antagonism prevented ET-1-stimulated vascular proinflammatory effects in both WKY and SHRSP VSMC. Proinflammatory effects of ET-1 in VSMCs are mediated via both ET_A and ET_B receptor subtypes. These effects may be abrogated by the PPAR-γ activator rosiglitazone. PPAR-γ activators may thus prevent deleterious ET-1-dependent proinflammatory vascular effects in VSMC in hypertension.