Efficacy and safety of intravenous ciprofloxacin in the treatment of serious infections. A comparison with ceftazidime.

Intravenous ciprofloxacin (200 mg every 12 hours) was compared with intravenous ceftazidime (1 g every eight hours) as therapy for 62 episodes of severe infections occurring in 60 adult patients, all of whom failed previous antimicrobial therapy. The study was designed as a prospective, controlled, randomized, non-blinded trial in a tertiary university care center. A variety of infections including skin and skin structure, urinary tract, bacteremia, pneumonia, and intra-abdominal infections were treated. Clinical cure was achieved in 83.3 percent (25 of 30) of patients treated with ciprofloxacin and in 87 percent (26 of 30) of patients treated with ceftazidime (p = 0.4). Bacteriologic and overall responses were also similar in both treatment groups (p = 0.4 and 0.375, respectively). Intravenous ciprofloxacin administered twice daily is an effective treatment for severe infections caused by susceptible organisms.

Ectopic bone formation is enhanced in senescent animals implanted with embryonic cells.

Ectopic bone formation induced by the subcutaneous implantation of demineralized bone matrix (DBM) is very significantly reduced in older Fischer 344 rats. Cells originating from calvaria of 20-day-old embryo donors were introduced into cylinders of DBM sealed at the ends with a Millipore filter or collagen sponges prior to subcutaneous implantation. Cells within the chambers had access to vascular channels that could penetrate through the interstices of the DBM. After four weeks of implantation in 26-month-old rats, the cylinders were full of bone. This bone was assessed by histologic techniques, by calcium and bone gamma-carboxyglutamic acid (gla) protein (BGP) concentrations, and by alkaline phosphatase activity. Cylinders to which no cells were added produced no bone. Bone marrow cells enclosed in similar cylinders or injected weekly at the implantation site also enhanced new bone formation but to a much lesser extent. Embryonic muscle cells formed large amounts of cartilage and less bone. Fibroblasts were inactive in this system. Prior treatment of the DBM with trypsin inhibited the myoblast response but not that of calvaria cells.

Biosynthesis of the yeast cell wall: selective assays and regulation of some mannosyl transferase activities.

Assays have been developed for some transfer reactions involved in the synthesis of Saccharomyces cerevisiae wall mannoproteins, both in a particulate preparation in the presence of EDTA or Triton X-100, and after lipid extraction with chloroform-methanol at -20 C. The mannosyl transferase activities were also studied in cells made permeable to GDP-mannose by toluene-ethanol treatment ("in situ"). In these permeabilized cells, the glycosylating reactions dependent on lipid carriers (dolichol derivatives) did not function, but those independent of them were unaffected. The lipid-independent mannosyl transferase activities were partially inhibited by nucleotide diphosphates probably in a competitive manner. Increase of the nucleotide diphosphate pool "in vivo" might slow down the speed of the transfer reactions carried out by the mannan synthetase system.