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A fluorometric microplate assay was performed for the detection of respiratory burst activity in a human leukaemia cell line HL-60 by assessing oxidation of 2',7'-dichloro fluorescin diacetate (DCFH-DA). This method is based on the detection of DCFH oxidation due to the presence of hydrogen peroxide. In the present study, the antioxidant activity of a number of structurally related flavonoids of plant origin and some of their microbial transformation products (1-18) were evaluated., (Copyright 2003 John Wiley & Sons, Ltd.)

The natural and semi-synthetic analogs of substituted 1,4-benzoquinones were evaluated for in vitro cytotoxic and antioxidant activities. Maesanin, dihydromaesanin, maesanin dimethyl ether and isomeric mixtures of 3-[(Z)-10'-pentadecenyl]-benzoquinone derivatives exhibited cytotoxic activity against HL-60 cell line (IC50 values 4.5, 2.2, 0.43 and 2.8 microg/mL, respectively), while it was found to be inactive against ROS (Reactive Oxygen Species) generation in HL-60. In contrast, the isomeric acylated benzoquinones with shorter alkyl substituents, namely, 2-acetoxy-5-hydoxy-6-methyl-3-tridecyl-1,4-benzoquinone and 2-hydoxy-5-acetoxy-6-methyl-3-tridecyl-1,4-benzoquinone showed most prominent antioxidant and antiproliferative effect on HL-60 (IC50 values 6.2 and 2.2 microg/mL, respectively), as well as cytotoxicities against SK-MEL, KB, BT-549 and SK-OV-3 carcinomas (IC50 values <1.1-4.2 microg/mL). All benzoquinones were found to be inactive against cell aggregation and cell adhesion assays, thus showing no effect on immune responses and inflammation., (Copyright 2003 John Wiley & Sons, Ltd.)

The aerial parts of Centaurothamnus maximus yielded three cytotoxic guaianolides, chlorojanerin (1), cynaropicrin (2) and janerin (3). The structure elucidation of 1-3 was based on (1)H and (13)C NMR data, mainly 2D-NMR (1)H-(1)H COSY and (1)H-(13)C HETCOR experiments. Compounds 1-3 showed in vitro cytotoxic activity against human cancer cell lines of malignant melanoma (SK-MEL), epidermoid (KB), ductal (BT-549) and ovarian (SK-OV-3) carcinomas with IC(50) values of 2-6 microgram/mL. In addition, 12 sesquiterpene lactones (4-15), isolated previously from the aerial parts of Vicoa pentanema, were evaluated for cytotoxic and antimicrobial activities. 2alpha- Acetoxy-3beta-hydroxyalantolactone (10) and 8beta-hydroxyparthenolide (14) were found to be the main cytotoxic agents (IC(50) values of 2-6 microgram/mL against SK-MEL, BT-549 and SK-OV-3), while lactones 4, 5, 11 and 15 selectively inhibited the growth of human malignant melanoma (IC(50) value of 3.6-7.3 microgram/mL). Cell aggregation and cell adhesion assays, using HL-60 and HeLa cell lines, evaluated the effect of cytotoxic constituents 1-3, 10 and 14 on immune response and inflammation., (Copyright 2003 John Wiley & Sons, Ltd.)

Background: Patients who have undergone esophagectomy with extensive lymph node dissection under thoracolapalotomy for advanced esophageal carcinomas frequently need long-term nutrition support because of their inadequate oral intake. We have used tube enterostomy feeding for these patients not only immediately after the operations but also at home to prevent the development of malnutrition. Patients who receive long-term tube enterostomy feeding often suffer from skin problems around the enteral nutrition catheters. Once the catheter is removed, the patient with anticipated malnutrition is subsequently unable to receive beneficial enteral nutrition. We have developed a new enteral access system that is placed subcutaneously. This subcutaneously implanted enteral nutrition port makes possible intermittent and long-term enteral nutrition support not only for the postoperative period but also for home care., Methods: This system consists of the port (Infuse-a-Port, SMAP15 Snaplock Macro-Port Venous Access System; Strato Medical Co) and the enteral nutrition tube (Enteral Tube 8F, 75 cm; Zeon Co). This system was applied to seven patients who had undergone esophagectomy. The port was placed on the lower chest subcutaneously, and the catheter was placed through the gastric tube and duodenum up to the jejunum. After the operation, a 20-gauge port needle was placed, and enteral nutrition formula (Enterued; Termo Co) was started with the enteral nutrition pump., Results: No complications (eg, infection of skin, obstruction of tube) were observed from the postoperative period through the home care stage. The observation period for this implanted system ranged from 2 to 12 months. The patients were able to avoid the malnutrition anticipated after the extensive operations and continued to receive nutrition support safely and effectively at home., Conclusion: This new nutrition support system is safe and efficient for patients who anticipate long-term enteral nutrition support. A subcutaneously implanted enteral nutrition port makes possible intermittent and long-term nutrition support without patient discomfort and inconvenience.

A new combined bioreactor-separator system was designed and its operational feasibility demonstrated in order to develop a bioprocess that enables us to handle simultaneous biotransformation and recovery of product by crystallization. Enzymatic conversion of L-aspartate to L-alanine by L-aspartate beta-decarboxylase from Pseudomonas dacunhae (ATCC 21192) was used as a model system for this study to demonstrate the principles involved in the bioprocess design. Immobilized cells of P. dacunhae containing the enzyme were fluidized in a tapered column type of bioreactor and a filter-crystallizer combination was used as a separator unit in our experimental system.It was found that almost a theoretical yield was achieved, and the process control for both the bioreactor operation and separation was relatively easy. The Production systems, namely, the recirculating bioreactor separator combination system and the conventional batch reactor system, were analyzed and compared based on the results obtained form this study, and it was found that a significant cost reduction, by about 20%, can be achieved when the recirculating bioreactor-separator combination system was employed. Based on these findings, it is anticipated that the conceptual design of the bioreactor-separator combination system evaluated in this study has some potential for industrial application.