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1.
We measured serum soluble vascular endothelial growth factor receptor 1 (sVEGFR1) and receptor 2 (sVEGFR2) levels in healthy Japanese individuals in order to establish a reference value using a specific ELISA. Significant differences were observed in serum sVEGFR1 and sVEGFR2 levels between children and adults. To demonstrate the usefulness of the reference value for children, we measured serum sVEGFR1 and sVEGFR2 levels in children with diarrhea positive (D+) hemolytic uremic syndrome (HUS) as a preliminary study. Serum sVEGFR2 levels in children with HUS were markedly higher than those in healthy children from the onset of D + HUS. The reference value for healthy children in the present study will allow normal and pathological conditions to be discriminated from each other in future study  相似文献   
2.
Objective: To assess if arachnoid cells have the capability to present antigen and activate T-lymphocytes after stimulation by bloody cerebrospinal fluid (CSF), and to illuminate the mechanism of coagulation-initiated inflammation in the subarachnoid space after subarachnoid hemorrhage (SAH). Methods: Arachnoid cells were cultured, characterized, and examined by immunofluorescence for the basal expression of human leukocyte antigen-DR (HLA-DR). Expression of HLA-DR, after co-culturing arachnoid cells in vitro with bloody CSF, was investigated by immunofluorescence and flow cytometry (FCM). The variation of arachnoid cells' ultrastructure was observed by transmission electron microscope (TEM). Arachnoid cells were co-cultured with peripheral blood mononuclear cells (PBMCs). The content of soluble interleukin-2 receptor (sIL-2r) in culture medium was detected by enzyme-linked immunosorbent assay (ELISA). Results: (1) Arachnoid cells were successfully cultured for many passages. The immunofluorescent staining was positive for HLA-DR in over 95% of the human arachnoid cells. The punctate HLA-DR was distributed in cytoplasm and not in the karyon. (2) After co-culturing arachnoid cells in vitro with bloody CSF, numerous particles with strong fluorescence appeared in the cytoplasm on Day 6. On Day 8, the quantity of particles and fluorescent intensity were maximal. FCM showed that the percentage of HLA-DR expressing cells was (2.5±0.4)% at the first 5 d, increasing to (60.8±3.6)% on Day 7. (3) After co-culturing arachnoid cells in vitro with bloody CSF, many lysosome and secondary lysosome particles were present in the cytoplasm. Hyperplasia of rough endoplasmic reticulum and enlarged cysts were observed, with numerous phagocytizing vesicles also observed at the edge of the arachnoid cells. (4) Arachnoid cells stimulated by bloody CSF were co-cultured in vitro with PBMCs. The content of sIL-2r in the culture medium, having been maintained at around 1.30 ng/ml during the first 3 d, had increased by Day 4. The content of sIL-2r peaked 7.53 ng/ml on Day 7 and then reduced gradually. Conclusions: (1) Basic HLA-DR expression is present in arachnoid cells. (2) After stimulation by bloody CSF, arachnoid cells have the potential to serve as antigen presenting cells (APCs) and the ability to activate T-lymphocytes, indicating that arachnoid cells are involved in the mechanism of coagulation-initiated inflammation in the subarachnoid space after SAH.  相似文献   
3.
利用苯酚法、考马斯亮蓝G-250染色法、抗坏血酸法分别测定香蕉成熟过程中可溶性糖、可溶性蛋白、维生素C的含量变化以及淀粉用酸水解转化成葡萄糖后,测定葡萄糖含量,根据葡萄糖含量换算成淀粉含量.通过对比生、熟香蕉中可溶性糖、可溶性蛋白、维生素C、淀粉的含量来研究香蕉成熟过程中有机物含量的变化情况.结果显示:香蕉成熟过程中,可溶性糖、可溶性蛋白质含量均增加,而淀粉、维生素C含量却减少.  相似文献   
4.
INTRODUCTIONCiliaryneurotrophicfactor (CNTF)isanat urallyoccurringproteinwithamolecularmassofapproximately 2 2kDa .Itisexpressedinglialcellswithinthecentralandperipheralnervoussystems.CNTFstimulatesgeneexpression ,cellsurvivalordifferentiationinavarietyof…  相似文献   
5.
The effects of five domestic cooking methods, including steaming, microwaving, boiling, stir-frying, and stir-frying followed by boiling (stir-frying/boiling), on the nutrients and health-promoting compounds of broccoli were investigated. The results show that all cooking treatments, except steaming, caused significant losses of chlorophyll and vitamin C and significant decreases of total soluble proteins and soluble sugars. Total aliphatic and indole glucosinolates were significantly modified by all cooking treatments but not by steaming. In general, the steaming led to the lowest loss of total glucosinolates, while stir-frying and stir-frying/boiling presented the highest loss. Stir-frying and stir-frying/boiling, the two most popular methods for most homemade dishes in China, cause great losses of chlorophyll, soluble protein, soluble sugar, vitamin C, and glucosinolates, but the steaming method appears the best in retention of the nutrients in cooking broccoli. Project supported by the High-Tech R&D Program (863) of China (No. 2008AA10Z111), the National Natural Science Foundation of China (No. 30320974), the Fok Ying Tong Education Foundation of China (No. 104034), and the Program for New Century Excellent Talents in the University of China (No. NCET-05-0516)  相似文献   
6.
Ciliary neurotrophic factor (CNTF) has pleiotropic actions on many neuronal populations as well as on glia. Signal transduction by CNTF requires that it bind first to CNTF-R, permitting the recruitment of gp130 and LIF-R, forming a tripartite receptor complex. Cells that only express gp130 and LIF-R, but not CNTF-R are refractory to stimulation by CNTF. On many target cells CNTF only acts in the presence of its specific agonistic soluble receptors. We engineered a soluble fusion protein by linking the COOH-terminus of sCNTF-R to the NH2-terminus of CNTF. Recombinant CNTF/sCNTF-R fusion protein (Hyper-CNTF) was successfully expressed in COS-7 cells. The apparent molecular mass of the Hyper-CNTF protein was estimated from western blots to be 75 kDa. Proliferation assays of transfected BAF/3 cells in response to CNTF and Hyper-CNTF were used to verify the activity of the cytokines. The proliferative results confirmed that CNTF required homodimerization of the gp130, CNTF-R and LIF-R receptor subunit whereas Hyper-CNTF required heterodimerization of the gp130 and LIF-R receptor subunit. We concluded that the fusion protein Hyper-CNTF had superagonistic activity on target cells expressing gp130 and LIF-R, but lacking membrane-bound CNTF-R. Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholar, Zhejiang Province, China and SFB415, TP B5, Germany.  相似文献   
7.
This technical note describes the construction and use of a portable silver nitrate test kit designed to be safely usable in the storeroom during collection condition surveys. It provides the surveying conservator with supplementary test data to better predict the level of hazard presented by soluble salts in collections.  相似文献   
8.
不同氮肥水平下烯效唑对小麦可溶性糖和淀粉含量的影响   总被引:2,自引:0,他引:2  
试验采用两因素裂区设计研究了不同氮肥水平下烯效唑对小麦可溶性糖和淀粉含量的影响。结果表明:烯效唑虽然降低了单位重量(g)中的淀粉含量,但增加了旗叶中可溶性糖的输出率,有力地保证了籽粒灌浆物质的来源,最终运输到籽粒中的碳素绝对量有所增加,因此淀粉产量增加。  相似文献   
9.
以烤烟品种云烟85种子为实验材料,从种子吸水前0h和吸水后的24h,48h,72h,96h,120h,144h,168h分8个时期分析了烟草种子萌发时各种养分的动态变化。结果表明:种子萌发至168h时,种子内可溶性总糖和还原糖含量达最大值,随后可溶性总糖和还原糖含量均维持在一个稳定的水平;种子萌发至24h时,种子内的蛋白质含量开始下降,至168h时达到最低;种子萌发至72h时,种子内的粗脂肪含量开始下降,至168h时达到最低。  相似文献   
10.
BackgroundPhospholipase D (PLD) is used as the biocatalyst for phosphatidylserine (PS) production. In general, PLD was expressed in insoluble form in Escherichia coli. High-level soluble expression of PLD with high activity in E. coli is very important for industrial production of PLD.ResultsStreptomyces chromofuscus PLD coding gene was codon-optimized, cloned without signal peptide, and expressed in E. coli. The optimal recombinant E. coli pET-28a+PLD/BL21(DE3) was constructed with pET-28a without His-tag. The highest PLD activity reached 104.28 ± 2.67 U/mL in a 250-mL shake flask after systematical optimization. The highest PLD activity elevated to 122.94 ± 1.49 U/mL by feeding lactose and inducing at 20°C after scaling up to a 5.0-L fermenter. Substituting the mixed carbon source with 1.0 % (w/v) of cheap dextrin and adding a feeding medium could still attain a PLD activity of 105.81 ± 2.72 U/mL in a 5.0-L fermenter. Fish peptone from the waste of fish processing and dextrin from the starch are both very cheap, which were found to benefit the soluble PLD expression.ConclusionsAfter combinatorial optimization, the high-level soluble expression of PLD was fulfilled in E. coli. The high PLD activity along with cheap medium obtained at the fermenter level can completely meet the requirements of industrial production of PLD.How to cite: Wu R, Cao J, Liu F, et al. High-level soluble expression of phospholipase D from Streptomyces chromofuscus in Escherichia coli by combinatorial optimization. Electron J Biotechnol 2021;50.https://doi.org/10.1016/j.ejbt.2020.12.002  相似文献   
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