With the application of the oligodynamic bactericidal property of silver ions, modification of the urinary catheter and drainage system has been found effective in the prevention of urinary tract infections owing to prolonged bladder catheterization. The newly devised catheter and open drainage system were used in 102 patients for bladder catheterization postoperatively or in those with urinary retention for periods ranging from 4 to 77 days. During the period of indwelling catheterization usually no antibiotics were administered and no patient had overt bacteriuria (more than 10(5) bacteria per ml.) or symptoms of urethritis. In contrast, all 20 patients in the control group who had the conventional type of indwelling catheters had bacteriuria within 4 days of catheterization. The data obtained indicate that effective prevention of urinary tract infection, which frequently is associated with indwelling urethral catheterization, can be achieved by the use of the modified catheter and drainage system.

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ABSTRACT:Soft, moderately polar resins were prepared from isomeric mixtures of m-and p-[3-(3-methyl-or 3-ethyl-3-oxetanyl)-2-oxapropyl]styrenes via a cationic ring-opening polymerization of their oxetanyl groups with BF3 THF followed by radical polymerization of styryl groups of the resultant polyoxetanes with AIBN, or via inverted polymerization. 3-(6-Bromo-2-oxahexyl)-3-methyloxetane, its 3-ethyl analogue, and a m-and p-isomeric mixture of chloromethylstyrene were used as comonomers in the above resin synthesis for obtaining the polymeric supports with the terminal alkyl bromide and the benzyl chloride in the side chain. Divinylbenzene was also used for preparing polymeric supports of the bead type by suspension polymerization. These pendant halides were quaternized with tributylamine or -phosphine to produce polymeric phase-transfer catalysts which could catalyze etherification reactions of alcohols with alkyl bromides in hexane and 50% aqueous NaOH. The beads with a pendant quaternary ammonium bromide were conveniently and repeatedly used in this reaction giving an ether product in 65-70% yields.KEY WORDS Polyoxetane-Polystyrene Composite Resins / Two-Stage Polymerization / Functional Polymers/ Phase-Transfer Catalysis / So far, a variety of functionalized polymers has been synthesized by using various polymeric supports. 1 Among these polymeric supports, divinylbenzene (10)-cross-linked polystyrenes are the most available and used most widely. 2 -4 However, the characters of the polystyrene supports are not always suitable for the chemical modification of their aromatic rings or pendant functional groups because of the hardness, low polarity, and hydrophobicity, especially when polar or ionic reagents and solvents are used.In our investigation to create softer, more polar polymer matrixes than those of polystyrene resins, we found two types of new crosslinking agents: l ,8-bis(3-methyl-3-oxetanyl)-2, 7-dioxaoctane (4a) and an isomeric mixture of m-and p-[3-(3-methyl-3-oxetanyl)-2-oxapropyl]styrenes (6a). 5 · 6 These agents were successfully used for preparing insoluble crosslinked polymers containing soft, moderately polar polyether networks by copolymerization with several monomers carrying functional groups at the pendant spacer end. Furthermore, the bifunctional monomers 6a and 6b with both oxetanyl and styryl groups are considered to be important key compounds for obtaining various functional polymers by cationic ring-opening or radical copolymerizations using cyclic ethers or vinyl compounds, which have pendant functional groups, as a comonomer. Accordingly, we have prepared several cross-linked polymeric supports by two processes of two-stage polymerizations. In one of these processes, the oxetane rings of 6a and 6b were cationically polymerized with or with- Concerning one application of such resins to functional polymeric supports, a phase-transfer catalysis of quaternary ammonium halides attached to the pendant spacer end of polyoxetane~polystyrene resins has been briefly reported by us on etherif...

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