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991.

Background  

Hypersplenism is traditionally treated by surgical splenectomy. Transcatheter ablation of splenic parenchyma is an alternative treatment modality.  相似文献   
992.
Hepatocellular carcinoma is the most common primary tumor of the liver accounting for 4.6% of all new human cancers. Cardiac metastasis in hepatocellular carcinoma is an uncommon secondary cardiac malignancy. We described two cases of advanced hepatocellular carcinoma with large masses in the right atrium mimicking atrial myxoma. The RA masses were incidentally detected during two-dimensional echocardiographic examination. (Echocardiography 2010;27:80-83)  相似文献   
993.
To compare the efficacy and safety of leflunomide (LEF)-anti-TNF-alpha combination therapy to methotrexate (MTX)-anti-TNF-alpha combination therapy in a group of patients with active rheumatoid arthritis (RA). We have recruited 120 patients with RA with a high disease activity despite being treated with MTX (15 mg/week) or LEF (20 mg/die) for 3 months, without side effects. In each of these patients, therapy with either MTX or LEF was continued and randomly combined with an anti-TNF-alpha drug: etanercept, infliximab, or adalimumab. Patients were assessed at study entry and at 4, 12, and at 24 weeks. The efficacy endpoints included variations in the DAS28-ESR and the ACR20, ACR50, and ACR70 responses. At each visit, any side-effect was recorded. There were no statistically significant differences in the DAS28 variations and in the ACR responses between the two groups or among the six subgroups. The number of discontinuation due to the appearance of serious side effects was higher, but not statistically significant, in the LEF-anti-TNF-alpha group than in the MTX-anti-TNF-alpha group. Other adverse events that did not necessitate the discontinuation of therapy occurred much more frequently in patients treated with MTX than in those treated with LEF. Anti-TNF-alpha drugs can be used in combination not only with MTX, but also with LEF, with the same probability of achieving significant clinical improvement in RA patients and without a significantly greater risk of serious adverse events. In contrast, it seems that combination therapy with LEF-anti-TNF-alpha is more readily tolerated than combination therapy with MTX-anti-TNF-alpha.  相似文献   
994.
A new series of 4-hydroxycoumarin derivatives 3a-d was synthesized by the reaction of 3-bromo-4-hydroxy coumarin 1 with various heteroaldehydes 2a-d in good yields. The synthesized compounds were characterized on the basis of their elemental and spectral (IR, (1)H-NMR and mass spectrometry) analysis. All target compounds were evaluated for their in-vitro antimicrobial activity against Streptococcus pyogenes, methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, Klebsiella pneumonia, and Escherichia coli bacterial strains and fungal cultures of Candida albicans, Aspergillus fumigatus, Trichophyton mentagrophytes, and Penicillium marneffei by disk diffusion assay with slight modifications. The minimum inhibitory concentration (MIC) was determined for the test compounds as well as for reference standards. Among the tested compounds, 3a has shown the most potent antibacterial as well as antifungal activities.  相似文献   
995.
Synthesis of a new series of 3,4-diarylpyrazole-1-carboxamide derivatives is described. Their antiproliferative activity against A375P human melanoma cell line was tested and the effect of substituents on the diarylpyrazole scaffold was investigated. The biological results indicated that five synthesized compounds (Ig, Ii, IIc, IIg, and IIh) exhibited similar activity to Sorafenib. In addition, three compounds (IIa, IIb, and IIi) were more potent than Sorafenib. Among all of these derivatives, compound IIa which has dimethylamino and phenolic moieties showed the most potent antiproliferative activity against A375P human melanoma cell line. Virtual screening was carried out through docking of the most potent compound IIa into the domain of V600E-b-Raf and the binding mode was studied.  相似文献   
996.
Physiological changes that take place at cellular level are usually reflective of their level of gene expression. Different formulation excipients have an impact on physiological behavior of the exposed cells and in turn affect transporter genes, enterocyte-mediated metabolism and toxicity biomarkers. The aim of this study was to prepare solid dispersion of paracetamol and evaluate genetic changes that occur in Caco-2 cell lines during the permeability of paracetamol alone and paracetamol solid dispersion formulations. Paracetamol-PEG 8000 solid dispersion was prepared by melt fusion method and the formulation was characterised using differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Formulation of solid dispersion resulted in the conversion of crystalline drug into an amorphous form. Permeability studies showed that paracetamol absorption was higher from the solid dispersion formulation. DNA microarrays analysis was carried out in order to investigate the involvement of any efflux/uptake transporters in paracetamol or its solid dispersion permeability. Neither transporter carriers nor efflux proteins were found to be involved in the absorption of paracetamol or its PEG solid dispersion. Gene expression analysis established that paracetamol toxicity was potentially reduced upon formulation into solid dispersion when ATP binding cassette (ABC) and solute carrier transporter (SLC) genes were analyzed.  相似文献   
997.
Recently, there is a growing interest in the cardiovascular beneficial effects of green tea. Epidemiological and clinical studies have suggested that consumption of green tea is inversely associated with the risk of developing cardiovascular diseases. Catechins, the major flavonoid constituents of green tea, exert cardioprotective effects through diverse mechanisms that include reversal of endothelial dysfunctions, decreasing inflammatory biomarkers, and providing antioxidant, antiplatelet and antiproliferative effects. Moreover, dietary consumption of green tea catechins has beneficial effects on blood pressure and lipid parameters. This review will focus on discussing the latest research on the cardioprotective effects of green tea catechins and their underlying molecular mechanisms. Several recent patents pertinent to green tea and cardiovascular health will also be discussed. It is noteworthy that clinical studies involving green tea are fraught with multiple complexity and confounding factors. Therefore, a rigorous assessment of the effects of green tea catechins in well-controlled human trials will be required for better understanding of the effects of green tea in cardiovascular health.  相似文献   
998.
Oo ZY  Deng R  Hu M  Ni M  Kandasamy K  bin Ibrahim MS  Ying JY  Zink D 《Biomaterials》2011,32(34):8806-8815
Bioartificial kidneys (BAKs) containing human primary renal proximal tubule cells (HPTCs) have been applied in clinical trials. The results were encouraging, but also showed that more research is required. Animal cells or cell lines are not suitable for clinical applications, but have been mainly used in studies on BAK development as large numbers of such cells could be easily obtained. It is difficult to predict HPTC performance based on data obtained with other cell types. To enable more extensive studies on HPTCs, we have developed a bioreactor containing single hollow fiber membranes that requires relatively small amounts of cells. Special hollow fiber membranes with the skin layer on the outer surface and consisting of polyethersulfone/polyvinylpyrrolidone were developed. The results suggested that such hollow fiber membranes were more suitable for the bioreactor unit of BAKs than membranes with an inner skin layer. An HPTC-compatible double coating was applied to the insides of the hollow fiber membranes, which sustained the formation of functional epithelia under bioreactor conditions. Nevertheless, the state of differentiation of the primary human cells remained a critical issue and should be further addressed. The bioreactor system described here will facilitate further studies on the relevant human cell type.  相似文献   
999.
Polyethylenimine (PEI) based polymers are efficient agents for cell transfection. However, their use has been hampered due to high cell death associated with transfection thereby resulting in low efficiency of gene delivery within the cells. To circumvent the problem of cellular toxicity, metal binding peptides were linked to PEI. Eight peptide-PEI derivatives were synthesized to improve cell survival and transfection efficiency. TAT linked PEI was used as a control polymer. Peptides linked with PEI amines formed nanogels as shown by electron microscopy and atomic force microscopic measurements. Polymers were characterized by spectroscopic methods and their ability to form complexes with plasmids was tested using electrophoretic studies. These modifications improved polymer biocompatibility as well as cell survival markedly, when compared to PEI alone. A subset of the modified peptide-polymers also showed significantly higher transfection efficiency in primary human cells with respect to the widely used transfection agent, lipofectamine. Study of the underlying mechanism of the observed phenomena revealed lower levels of 'reactive oxygen species' (ROS) in the presence of the peptide-polymers when compared to PEI alone. This was further corroborated with global gene expression analysis which showed upregulation of multiple genes and pathways involved in regulating intracellular oxidative stress.  相似文献   
1000.
This study investigated the oxidative stress induced after acute oral treatment with 500, 1000 and 2000 mg kg?1 doses of Al2O3‐30 and ?40 nm and bulk Al2O3 in Wistar rats. Both the nanomaterials induced significant oxidative stress in a dose‐dependent manner in comparison to the bulk. There was no significant difference between the two nanomaterials. However, the effect decreased with increase with time after treatment. The histopathological examination showed lesions only in liver with Al2O3 nanomaterials at 2000 mg kg?1. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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