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521.
Molecular Biology Reports - The caprine mesenchymal stem cells (MSCs) derived from fetal adnexa are highly proliferative. These cells possess tri-lineage differentiation potential and express MSC...  相似文献   
522.
The function of Sprouty2 (Spry2) in T cells is unknown. Using 2 different (inducible and T cell–targeted) knockout mouse strains, we found that Spry2 positively regulated extracellular signal-regulated kinase 1/2 (ERK1/2) signaling by modulating the activity of LCK. Spry2−/− CD4+ T cells were unable to activate LCK, proliferate, differentiate into T helper cells, or produce cytokines. Spry2 deficiency abrogated type 2 inflammation and airway hyperreactivity in a murine model of asthma. Spry2 expression was higher in blood and airway CD4+ T cells from patients with asthma, and Spry2 knockdown impaired human T cell proliferation and cytokine production. Spry2 deficiency up-regulated the lipid raft protein caveolin-1, enhanced its interaction with CSK, and increased CSK interaction with LCK, culminating in augmented inhibitory phosphorylation of LCK. Knockdown of CSK or dislodgment of caveolin-1–bound CSK restored ERK1/2 activation in Spry2−/− T cells, suggesting an essential role for Spry2 in LCK activation and T cell function.

The ubiquitously expressed protein Sprouty2 (Spry2) is a known regulator of Ras/ERK signaling pathway. This study uses in vitro and in vivo models, as well as human specimens, to reveal a mechanism for Spry2 in positively regulating ERK activation in CD4+ T-cells.  相似文献   
523.
In the present investigation, we employ a dual approach consisting of experimental and computational techniques to synthesise and characterise the Schiff-base including the moieties of nitrophenyl (3), nitrothiazole (5) and nitrobenzothiazole (7). The synthesised Schiff bases are confirmed by FT-IR, 1H-NMR and UV-visible spectroscopic techniques. The experimental UV-visible spectroscopic results are compared to the theoretically calculated TD-DFT results. There is a reasonably good agreement between the experimental and the theoretically calculated spectroscopic results. We also calculate the third-order nonlinear optical (NLO) polarizability (γ) of above entitled derivatives using finite field (FF) approach and DFT methods. The compound 7 shows an amplitude of γ as large as 124.15×104 a. u., which is found to be several times larger than that of para-nitroaniline. Moreover, the partial and total density of states (PDOS and TDOS) along with electrostatic potential maps are calculated to get more physical insights into the structure-property relationship and electronic communications between terminal donor and central core acceptor moieties in the synthesised compounds. The present investigation highlights the significance of indigenously synthesised nitrothiazole and nitrobenzothiazole compounds as efficient NLO materials, which may evoke the interest of scientific community in such efficient NLO materials for their potential utilization in device applications.  相似文献   
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525.
Vectors containing elements of the Epstein-Barr virus genome are used primarily to maintain cloned DNA inserts as plasmids in mammalian cells. However, Epstein-Bar-virus-based vectors have also been valuable tools in the hands of those studying the life cycle of Epstein-Barr virus. In this article, we discuss those characteristics of Epstein-Barr virus and its life cycle that have been used in vector construction and describe methods that are particularly applicable to the use of Epstein-Barr-virus-based vectors.  相似文献   
526.
Depth filtration-based harvesting is widely used in mAb manufacturing to remove cell and process-related impurities. However, it has not been studied on control of product-related impurities, which are very critical for product quality. In this article, we studied the interactions of depth filter with high and low molecular weight species (HMWs and LMWs) for their direct removal from cell culture. The process parameters (filter, loading, temperature, and flux) were evaluated for adsorption of HMWs and LMWs by depth filters. The adsorption is significantly dependent on filter media and loading capacity and is mainly on the basis of hydrophobic interaction during harvesting. The HMW and LMW species were characterized as HMW1, HMW2, LMW1, and LMW2. The increasing binding from LMW2 to LMW1, HMW1, and HMW2 is correlated with their increasing hydrophobicity score. Adsorption using enriched HMW sample demonstrated similar total protein binding capacity (36–40 g/m2) between depth filters D0HC and X0HC. However, X0HC has stronger HMW binding than D0HC (71% vs 43% of bound protein), indicating more hydrophobic interaction in X0HC. HMW2 DBC on X0HC reached 12 g/m2, similar to protein binding on hydrophobic interaction membrane adsorbers. Further study showed LMW can induce HMW formation. This study provides a critical understanding of HMW and LMW interaction with depth filters. The strategy of HMW and LMW control by depth filtration-based harvesting was implemented successfully in mAb manufacturing.  相似文献   
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