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101.
Bacille Calmette–Guérin (BCG) immunization provides variable protection against tuberculosis. Prenatal antigen exposure may have lifelong effects on responses to related antigens and pathogens. We therefore hypothesized that maternal latent Mycobacterium tuberculosis infection (LTBI) influences infant responses to BCG immunization at birth. We measured antibody (n = 53) and cellular (n = 31) responses to M. tuberculosis purified protein derivative (PPD) in infants of mothers with and without LTBI, in cord blood and at one and six weeks after BCG. The concentrations of PPD-specific antibodies declined between birth (median [interquartile range (IQR)]) 5600 ng ml−1 [3300–11 050] in cord blood) and six weeks (0.00 ng ml−1 [0–288]). Frequencies of PPD-specific IFN-γ-expressing CD4+T cells increased at one week and declined between one and six weeks (p = 0.031). Frequencies of IL-2- and TNF-α-expressing PPD-specific CD4+T cells increased between one and six weeks (p = 0.019, p = 0.009, respectively). At one week, the frequency of PPD-specific CD4+T cells expressing any of the three cytokines, combined, was lower among infants of mothers with LTBI, in crude analyses (p = 0.002) and after adjusting for confounders (mean difference, 95% CI −0.041% (−0.082, −0.001)). In conclusion, maternal LTBI was associated with lower infant anti-mycobacterial T-cell responses immediately following BCG immunization. These findings are being explored further in a larger study.  相似文献   
102.

Background

Hormone-refractory prostate cancer (HRPC), which is resistant to hormone therapy, is a major obstacle in clinical treatment. An approach to inhibit HRPC growth and ultimately to kill cancers is highly demanded.

Results

KUD773 induced the anti-proliferative effect and subsequent apoptosis in PC-3 and DU-145 (two HRPC cell lines); whereas, it showed less active in normal prostate cells. Further examination showed that KUD773 inhibited tubulin polymerization and induced an increase of mitotic phosphoproteins and polo-like kinase 1 (PLK1) phosphorylation, indicating a mitotic arrest of the cell cycle through an anti-tubulin action. The kinase assay demonstrated that KUD773 inhibited Aurora A activity. KUD773 induced an increase of Cdk1 phosphorylation at Thr161 (a stimulatory phosphorylation site) and a decrease of phosphorylation at Tyr15 (an inhibitory phosphorylation site), suggesting the activation of Cdk1. The data were substantiated by an up-regulation of cyclin B1 (a Cdk1 partner). Furthermore, KUD773 induced the phosphorylation and subsequent down-regulation of Bcl-2 and activation of caspase cascades.

Conclusions

The data suggest that KUD773 induces apoptotic signaling in a sequential manner. It inhibits tubulin polymerization associated with an anti-Aurora A activity, leading to Cdk1 activation and mitotic arrest of the cell cycle that in turn induces Bcl-2 degradation and a subsequent caspase activation in HRPCs.  相似文献   
103.
Wang F  Gu Z  Cui Z  Liu L 《Bioresource technology》2011,102(20):9374-9379
α-Amylase from Aspergillus oryzae was covalently immobilized onto polystyrene pellets with pentaethylenehexamine (PS-PEHA-Ald) and pentaethylene glycol (PS-PG-Ald) carrying a terminal aldehyde group. Optimum immobilization occured at pH 8.0 and 25 °C, and at pH 7.0 and 35 °C for PS-PEHA-Ald and PS-PG-Ald, respectively. PS-PEHA-Ald immobilized enzyme retained approximately 75% of the initial activity over 45 days of storage, 70% of the initial activity after nine runs of recycling and displayed the better resistance to detrimental metal ions. PS-PG-Ald immobilized enzyme retained approximately 50% of the initial activity in 8h at 70 °C. The catalytic efficiencies of PS-PEHA-Ald immobilized and PS-PG-Ald immobilized amylase were 1.42 and 1.29 times higher than that of native enzyme. The activation energy of the reaction mediated by the amylase was reduced by 58.1% and 57.3% when PS-PEHA-Ald and PS-PG-Ald used as support respectively.  相似文献   
104.
We report, for the first time, that certain N-acetylthiourea derivatives serve as highly potent and isozyme selective activators for the recombinant form of human histone deacetylase-8 in the assay system containing Fluor-de-Lys as a fluorescent substrate. The experimental data reveals that such activating feature is manifested via decrease in the K(m) value of the enzyme's substrate and increase in the catalytic turnover rate of the enzyme.  相似文献   
105.
A new series of 3-phenyl-N-[3-(4-phenylpiperazin-1yl)propyl]-1H-pyrazole-5-carboxamide derivatives were synthesized and investigated their anti-inflammatory activities using carrageenan-induced rat paw edema model in vivo. All the synthesized compounds were found to be potent anti-inflammatory agents.  相似文献   
106.
New derivatives of 1,4-dideoxy-1,4-imino-d-ribitol have been prepared and evaluated for their cytotoxicity on solid and haematological malignancies. 1,4-Dideoxy-5-O-[(9Z)-octadec-9-en-1-yl]-1,4-imino-d-ribitol (13, IC50 ∼2 μM) and its C18-analogues (IC50 <10 μM) are cytotoxic toward SKBR3 (breast cancer) cells. 13 also inhibits (IC50 ∼8 μM) growth of JURKAT cells.  相似文献   
107.
108.
Viguiera oblongifolia afforded two known furanoheliangolides and a new cadinane derivative whose structure was established by spectroscopic methods. From V. lanceolata 17,18-dihydrobudlein A was isolated.  相似文献   
109.
In the present paper, we report the study of the adsorption behaviour of human immunoglobulin G (IgG), human serum albumin (HSA) and polyethylenimine (PEI) onto surfaces of Procion Green HE-4BD (PG) immobilized poly(hydroxyethylmethacrylate) (pHEMA) membranes. The adsorption behaviour of the IgG and HSA onto surfaces of the PG–PEI complexed membrane was also studied. Surface wettability and hydrophilicity of all the membranes were investigated by static contact angle measurements. The measurements of the contact angle to various test liquids, i.e., water, glycerol, formamide, diiodomethane (DIM) and ethylene glycol on the investigated membranes were made by sessile drop method. In accordance to the Young equation, the smaller the surface tension of the test liquid, the smaller becomes the contact angles measured on all the investigated membranes surfaces. The highest contact angles were obtained with water, whereas ethylene glycol gave the lowest contact angles for all the tested membranes. Component and parameters of the surface free energy of all the investigated membranes were calculated from measured contact angle values using two methods (the geometric mean by Fowkes and acid–base by van Oss). HSA adsorption was enhanced after complexation of PEI with the immobilized dye-ligand. The adsorption of proteins and PEI significantly changed both the contact angles and component of surface free energies of the investigated membranes.  相似文献   
110.
BACKGROUND: The available methods for administration of gene delivery systems to the lungs of small animals via nebulization have several drawbacks. These include lack of control over the delivered dose and a negative impact on the stability of the formulation. This paper describes a new nebulization catheter device for the administration of plasmid-based gene delivery systems (polyplexes) as aerosols to the mouse lung in vivo. METHODS: The physical stability of naked pDNA and polyplexes formulated with chitosan oligomers and PEI was examined following nebulization with the catheter device. We also examined the in vitro transfection efficiency of the polyplexes recovered after nebulization. Lung distribution and gene expression after administration of the selected gene delivery systems to the mouse lung were also investigated. RESULTS: In contrast to previously described nebulization methods, the structural integrity of the unprotected naked pDNA was maintained following nebulization by the catheter device, which indicates relatively mild nebulization conditions. In addition, the nebulization procedure did not affect the physical stability of the formulated polyplexes. Small volumes of the pDNA aerosol (10-20 microl) were delivered in a highly controlled and reproducible manner. The aerosol droplet size varied with the molecular weight of the polycations. Aerosol delivery via this method resulted in improved lung distribution of pDNA polyplexes and a six-fold increase in the efficiency of gene delivery in vivo over that seen with the commonly used intratracheal instillation method. CONCLUSION: The use of the nebulization catheter device provides a promising alternative for aerosol gene delivery to the mouse lung.  相似文献   
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