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41.
The endothelial cells that form capillaries in the brain are highly specialized, with tight junctions that minimize paracellular transport and an array of broad-spectrum efflux pumps that make drug delivery to the brain extremely challenging. One of the major limitations in blood-brain barrier research and the development of drugs to treat central nervous system diseases is the lack of appropriate cell lines. Recent reports indicate that the derivation of human brain microvascular endothelial cells (hBMECs) from human induced pluripotent stem cells (iPSCs) may provide a solution to this problem. Here we demonstrate the derivation of hBMECs extended to two new human iPSC lines: BC1 and GFP-labeled BC1. These hBMECs highly express adherens and tight junction proteins VE-cadherin, ZO-1, occludin, and claudin-5. The addition of retinoic acid upregulates VE-cadherin expression, and results in a significant increase in transendothelial electrical resistance to physiological values. The permeabilities of tacrine, rhodamine 123, and Lucifer yellow are similar to values obtained for MDCK cells. The efflux ratio for rhodamine 123 across hBMECs is in the range 2–4 indicating polarization of efflux transporters. Using the rod assay to assess cell organization in small vessels and capillaries, we show that hBMECs resist elongation with decreasing diameter but show progressive axial alignment. The derivation of hBMECs with a blood-brain barrier phenotype from the BC1 cell line highlights that the protocol is robust. The expression of GFP in hBMECs derived from the BC1-GFP cell line provides an important new resource for BBB research.  相似文献   
42.
A two-chain, disulfide linked, insulin-like compound embodying the A-domain of insulin-like growth factor I (IGF-I) and the B-chain of insulin has been synthesized and characterized with respect to insulin-like biological activity and growth-promoting potency. The compound displays a potency of ca. 41% relative to insulin in assays for insulin-like activity (e.g., lipogenesis) but significantly higher activity than insulin, ca. 730% relative to insulin, in growth factor assays (e.g., thymidine incorporation). The compound is, however, a less potent growth factor than IGF-I itself, ca. 26.5% relative to IGF-I, and is not recognized by IGF carrier proteins. We conclude that structural features contained in the A-domain of IGF-I are primarily responsible for the growth-promoting ability displayed by IGF-I, while features in the B-domain are responsible for recognition by IGF carrier proteins.  相似文献   
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To evaluate and compare the effect of raw and processed pyritum on tibial defect healing, 32 male Sprague Dawley rats were randomly divided into four groups. After tibial defect, animals were produced and grouped: sham and control group were orally administrated with distilled water (1 mL/100 g), while treatment groups were given aqueous extracts of raw and processed pyritum (1.5 g/kg) for successive 42 days. Radiographic examination showed that bone defect healing effect of the treatment groups was obviously superior compared to that of the control group. Bone mineral density of whole tibia was increased significantly after treating with pyritum. Inductively coupled plasma-optical emission spectrometry showed that the contents of Ca, P, and Mg in callus significantly increased in the treatment groups comparing with the control. Moreover, serological analysis showed that the concentration of serum phosphorus of the treatment groups significantly increased compared with that of the control group. By in vitro study, we have evaluated the effects of drug-containing serum of raw and processed pyritum on osteoblasts. It was manifested that both the drug-containing sera of raw and processed pyritum significantly increased the mRNA levels of alkaline phosphatase and collagen type I. Protein levels of phosphorylated Smad2/3 also increased. The mRNA levels of osteocalcin and transforming growth factor β (TGF-β) type I and II receptors, as well as the protein levels of TGF-β1 in the processed groups, were higher than those in the control. In summary, both raw and processed pyritum-containing sera exhibited positive effects on osteoblasts, which maybe via the TGF-β1/Smad signaling pathway. Notably, the tibia defect healing effect of pyritum was significantly enhanced after processing.  相似文献   
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This study investigated the protective effects of two polysaccharides (CPA-1 and CPB-2) from Cordyceps cicadae against high fructose/high fat diet (HF/HFD) induced obesity and metabolic disorders in rats. Rats were either fed with normal diet or HF/HFD and treated with CPA-1 and CPB-2 (100 and 300 mg/kg) for 11 weeks. Administration of CPA-1 and CPB-2 significantly and dose dependently reduced body and liver weight, insulin and glucose tolerance, serum insulin and glucose levels. Furthermore, serum and hepatic lipid profiles, liver function enzymes and proinflammatory cytokines (TNF-α, IL-1β and IL-6) were markedly reduced. Additionally, CPA-1 and CPB-2 treatment alleviated hepatic oxidative stress by reducing lipid peroxidation level (MDA) and upregulating glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase (CAT) activities as well as ameliorated histological alterations through the reduction of hepatic lipid accumulation. These results suggested that the polysaccharides from C. cicadae showed protective effects against HF/HFD induced metabolic disturbances and may be considered as a dietary supplement for treating obesity.  相似文献   
47.
The objective of this investigation was to find a simple method for the production of phenolic-rich products and sugar derivatives via separation of liquefied lignocellulosic materials. After liquefaction, the liquefied products were separated by addition of a sufficient amount of water. It was found that those hydrophobic phenolics could be largely separated from aqueous solutions. Preparation of polyurethane foams using biopolyol and isocyanate was studied. Water was used as an environmentally friendly blowing agent. The factors influencing the cell structure of foams such as catalyst, dosage of blowing agent, and mass ratio of biopolyol to PEG were studied. The microstructure of synthesized foams was characterized by SEM.  相似文献   
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Pallister-Killian syndrome (PKS) is a rare sporadic genetic disorder usually caused by mosaicism of an extra isochromosome of 12p (i(12p)). This retrospective study analysed the prenatal ultrasound manifestations and molecular and cytogenetic results of five PKS foetuses. Samples of amniotic fluid and/or cord blood, skin biopsy and placenta were collected. Conventional karyotyping and single nucleotide polymorphism array (SNP array) were performed on all the amniotic fluid or cord blood samples. Copy number variants sequencing (CNV-seq) and fluorescence in situ hybridization (FISH) were also used for the validation for one foetus. All the five foetuses were from pregnancies with advanced parental age. Two foetuses involved structural abnormalities and one foetus had only soft markers, all of which included increased nuchal translucency. The rest two foetuses had normal ultrasounds in the second trimester, which has rarely been reported before. The karyotype revealed typical i(12p) in four cases and a small supernumerary marker chromosome consisting of 12p and 20p in the remaining one case. The proportion of cells with i(12p) ranged from 0 to 100% in cultural cells, while SNP array results suggested 2−4 copies of 12p. For one foetus, metaphase FISH showed normal results, but the interphase FISH suggested cell lines with two, three and four copies of 12p in the amniotic fluid. Advanced parental age may be an important risk factor for PKS, and there were no typical ultrasound manifestations related to PKS. A combination of karyotype analysis and molecular diagnosis is an effective method for the diagnosis of PKS.  相似文献   
50.
Photosynthesis-irradiance (PI) curves are extensively used in field and laboratory research to evaluate the photon-use efficiency of plants. However, most existing models for PI curves focus on the relationship between the photosynthetic rate (Pn) and photosynthetically active radiation (PAR), and do not take account of the influence of environmental factors on the curve. In the present study, we used a new non-competitive inhibited Michaelis-Menten model (NIMM) to predict the co-variation of Pn, PAR, and the relative pollution index (I). We then evaluated the model with published data and our own experimental data. The results indicate that the Pn of plants decreased with increasing I in the environment and, as predicted, were all fitted well by the NIMM model. Therefore, our model provides a robust basis to evaluate and understand the influence of environmental pollution on plant photosynthesis.  相似文献   
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