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121.
Following incubation of mesophilic methanogenic floccular sludge from a lab-scale upflow anaerobic sludge bed reactor used to treat cattle manure wastewater, a stable 5-aminosalicylate-degrading enrichment culture was obtained. Subsequently, a Citrobacter freundii strain, WA1, was isolated from the 5-aminosalicylate-degrading methanogenic consortium. The methanogenic enrichment culture degraded 5-aminosalicylate completely to CH4, CO2 and NH4
+, while C. freundii strain WA1 reduced 5-aminosalicylate with simultaneous deamination to 2-hydroxybenzyl alcohol during anaerobic growth with electron donors such as pyruvate, glucose or serine. When grown on pyruvate, C. freundii WA1 converted 3-aminobenzoate to benzyl alcohol and also reduced benzaldehyde to benzyl alcohol. Pyruvate was fermented to acetate, CO2, H2 and small amounts of lactate, succinate and formate. Less lactate (30%) was produced from pyruvate when C. freundii WA1 grew with 5-aminosalicylate as co-substrate. 相似文献
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123.
Terenetskaya I 《The Journal of steroid biochemistry and molecular biology》2004,(1-5):623-626
Excessive UV exposures are commonly associated with adverse health effects, but proper amounts of UV are beneficial for people and essential in the natural production of Vitamin D(3) in skin. Two methods have been developed for direct evaluation of the Vitamin D synthetic capacity of sunlight (and artificial UV sources). The first one uses an in vitro model of Vitamin D(3) synthesis (ethanol solution of 7-dehydrocholesterol, 7-DHC), and concentration of previtamin D(3) accumulated during an UV exposure is determined using specially designed spectrophotometric analysis. The second method utilizes photoisomerization of provitamin D in nematic liquid crystalline (LC) matrix, and visual estimation of accumulated previtamin D becomes possible due to special design of a LC cell. This user-friendly method is appropriate for personal UV dosimetry and may have wide application in tanning saloons, in clinical dermatology and UV therapy. 相似文献
124.
Kristal BS Stavrovskaya IG Narayanan MV Krasnikov BF Brown AM Beal MF Friedlander RM 《Journal of bioenergetics and biomembranes》2004,36(4):309-312
Mitochondria serve as checkpoints and amplifiers on cell death pathways. In the central nervous system, mitochondrial involvement seems essential for normal expression of cell death phenotypes, and interference with these pathways thus seems a reasonable approach to neuroprotection. We have been involved in examining the potential involvement of the mitochondrial permeability transition (mPT) as one of several possible mechanisms by which mitochondria may be drawn into these death cascades. This possibility, though still controversial, is supported by evidence that factors that may stimulate mPT induction are associated with some forms of cell death (e.g., in stroke) and are modulated by diseases of the central nervous system (e.g., Huntington's). Evidence of neuroprotection seen with compounds such as N-Met-Val cyclosporine also support this possibility. 相似文献
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126.
Veinberg G Shestakova I Vorona M Kanepe I Domrachova I Lukevics E 《Bioorganic & medicinal chemistry letters》2004,14(4):1007-1010
Doxorubicin-cephalosporin prodrug adapted to the development of elastases for the liberation of parent drug was synthesized on the basis of cephalosporanate sulfone esters. 相似文献
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128.
We describe a method for repetitive and rapid formation of planar microarrays and gradients of proteins using patterned agarose stamps. It demonstrates: (i) micropatterning of agarose gels with feature sizes as small as 2 microm; (ii) inking of posts (diameter 50-1000 microm) on patterned agarose stamps with one or multiple (here, eight) proteins and repetitive stamping of patterns (>100 times in the case of one protein) and arrays (20 times in the case of eight proteins) without the need for intermediate re-inking; (iii) transferring spots of proteins with good homogeneity in surface coverage to glass slides; (iv) applying this technique to surface-based immunoassays; (v) stamping that requires only sub-nanomolar amounts of protein (typically approximately 3 microg in approximately 0.6 microL of solution); (vi) stamping without the need for drying of the proteins, as opposed to stamping with stamps made of poly(dimethylsiloxane); and (vii) patterning gradients of proteins by allowing two proteins to diffuse toward each other in an agarose stamp, followed by printing the protein gradients onto a surface. 相似文献
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130.
Celis JE Gromov P Cabezón T Moreira JM Ambartsumian N Sandelin K Rank F Gromova I 《Molecular & cellular proteomics : MCP》2004,3(4):327-344
Clinical cancer proteomics aims at the identification of markers for early detection and predictive purposes, as well as to provide novel targets for drug discovery and therapeutic intervention. Proteomics-based analysis of traditional sources of biomarkers, such as serum, plasma, or tissue lyzates, has resulted in a wealth of information and the finding of several potential tumor biomarkers. However, many of these markers have shown limited usefulness in a clinical setting, underscoring the need for new clinically relevant sources. Here we present a novel and highly promising source of biomarkers, the tumor interstitial fluid (TIF) that perfuses the breast tumor microenvironment. We collected TIFs from small pieces of freshly dissected invasive breast carcinomas and analyzed them by two-dimensional polyacrylamide gel electrophoresis in combination with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, Western immunoblotting, as well as by cytokine-specific antibody arrays. This approach provided for the first time a snapshot of the protein components of the TIF, which we show consists of more than one thousand proteins--either secreted, shed by membrane vesicles, or externalized due to cell death--produced by the complex network of cell types that make up the tumor microenvironment. So far, we have identified 267 primary translation products including, but not limited to, proteins involved in cell proliferation, invasion, angiogenesis, metastasis, inflammation, protein synthesis, energy metabolism, oxidative stress, the actin cytoskeleton assembly, protein folding, and transport. As expected, the TIF contained several classical serum proteins. Considering that the protein composition of the TIF reflects the physiological and pathological state of the tissue, it should provide a new and potentially rich resource for diagnostic biomarker discovery and for identifying more selective targets for therapeutic intervention. 相似文献