The effect of the kappa-opioid receptor agonist CI-977 in a rat model of focal cerebral ischaemia.

The effect of a novel, highly potent and selective kappa-opioid receptor agonist CI-977 upon ischaemic brain damage and brain swelling has been examined in a rat model of focal cerebral ischaemia. Focal ischaemia was produced by the permanent occlusion of the left middle cerebral artery (MCA) during a brief period of halothane anaesthesia. The animals were sacrificed 24 h after MCA occlusion and the amount of ischaemic brain damage and swelling was assessed in coronal sections at 8 predetermined stereotactic planes. Treatment with CI-977 (0.03, 0.3 or 3 mg/kg), initiated 30 min prior to MCA occlusion (and at multiple times thereafter) produced dose-dependent reductions in the volumes of infarction and of brain swelling, with the most marked reductions being noted with CI-977 (0.3 mg/kg) in both infarction (reduced by 38% from controls; P less than 0.02) and swelling (reduced by 31%; P less than 0.002). There was an excellent correlation between the volume of brain swelling and ischaemic damage which was similar with saline-treated and CI-977-treated animals (overall correlation coefficient r = 0.896). These results indicate that CI-977 is effective in reducing infarction in a model of focal cerebral ischaemia, and that the reduction in brain swelling occurs in parallel with the reduction in ischaemic damage.     

Basic and clinical studies of cefotiam in neonates and premature infants

The effect of cefotiam (CTM) on neonates and premature infants was examined in basic and clinical studies. Minimum inhibitory concentrations of CTM against 190 clinically isolated strains kept by this department were investigated. This drug was found to have a strong antibacterial effect against Escherichia coli, Klebsiella spp., Proteus mirabilis and Streptococcus agalactiae, Staphylococcus aureus and Staphylococcus epidermidis, although some strains were resistant. The CTM was given to 0-3, 4-7, and greater than or equal to 8 day-old premature infants and neonates by intravenous injection at the dose of 20 mg/kg, and we studied changes in serum CTM levels over time. Mean serum CTM levels were 62.3 micrograms/ml at 15 minutes and 16.4 micrograms/ml at 6 hours after the injection, with the half-life of 3.6 hours, for the 0-3 day-old premature infants. They were 38.5 micrograms/ml at 15 minutes and 10.1 micrograms/ml at 6 hours, with the half-life of 2.9 hours, for the 0-3 day-old neonates. Those levels were 22.5 micrograms/ml at 15 minutes and 2.9 micrograms/ml at 6 hours, with the half-life of 1.9 hours, for the 4-7 day-old neonates, and 51.8 micrograms/ml at 15 minutes and 1.0 micrograms/ml at 6 hours, with the half-life of 1.1 hours, for the greater than or equal to 8 day-old neonates. The CTM was given to 0-3 and greater than or equal to 8 day-old premature infants and neonates by 1-hour intravenous drip infusion at the dose of 20 mg/kg, and changes in serum CTM levels after the infusion were followed. The 0-3 day-old premature infant (there was only one subject) had a peak serum CTM level of 21.0 micrograms/ml 1 hour after the start of the infusion (that is, at the time of its completion), with the level decreased to 8.6 micrograms/ml at 7 hours and the half-life was 5.4 hours. The mean peak serum CTM level in 0-3 day-old neonates were 36.7 micrograms/ml at 1 hour, which decreased to a mean of 7.0 micrograms/ml at 7 hours; the half-life was 2.3 hours.(ABSTRACT TRUNCATED AT 400 WORDS)     

Intramuscular osteoinduction and bone marrow formation by the implantation of rhBMP-2 with atelopeptide type I collagen

The study examines the osteoinductive potential of recombinant human morphogenetic protein 2 (rhBMP-2) radiologically and histologically in rat calf muscle.Ten male Wistar rats were used. rhBMP-2 50 μg was implanted with atelopeptide type I collagen as carrier in a pouch in rat calf muscle (n=5), and atelopeptide type I collagen alone was implanted in a further five as control. Induction of osteogenesis at 4 weeks was investigated.In all rats in which rhBMP-2 had been implanted there was a radio-opaque shadow in the muscle in the soft tissue radiograph. No such shadows were noted in the control group. Histological examination showed bony trabeculum, osteoblasts, and vigorous bone marrow including fatty marrow and angioid tissue both at the margins and in the center of the excised lumps in the rhBMP-2 group. There were no such signs in the control group.rhBMP-2 may be capable not only of inducing the formation of bone, but also of inducing a ‘self-supporting bone organ’ in the muscle.     

Effect of meropenem on fecal flora in children]

Meropenem (MEPM, SM-7338), a novel parenteral carbapenem antibiotic, was examined for its effect on intestinal flora in children. Seven children with infectious diseases (3 male and 4 female children of age's ranging from 4 months to 8 years and 9 months weighing from 7.3 to 23.0 kg) were treated with MEPM at doses ranging 10.3 to 40.5 mg/kg 3 or 4 times a day for 6 to 12 days. Before, during and after the treatment, identities and numbers of various bacteria contained in 1 g of feces were determined and fecal beta-lactamase activity and Clostridium difficile D-1 antigen were also assayed. Changes in fecal flora during MEPM treatment was somewhat different depending on cases. Regarding Enterobacteriaceae among aerobes, all of 7 cases exhibited moderate or pronounced reductions in Escherichia coli. Some of the cases exhibited the tendency to increase in Klebsiella oxytoca. Enterobacter cloacae and Citrobacter freundii. E. coli which was reduced during the treatment increased rapidly after the treatment in 5 out of 7 cases, and the initial bacterial counts were restored. Diverse strains were observed within the genus Enterococcus, while the overall bacterial counts of this genus exhibited the tendency to increase during the treatment. As a result, no significant change in total aerobe count was observed in any case except 1 case where Enterococcus count was somewhat reduced. Among anaerobes, major bacteria such as Bacteroides, Bifidobacterium, Eubacterium and Peptococcaceae exhibited tendencies to decrease in some cases during the antibiotic treatment. Two infants and 1 child exhibited significant decreases in total anaerobe counts. In most of the cases, such changes in major anaerobes were transient and bacterial counts recovered to their initial values rapidly after completion of the treatment. In no cases, glucose non-fermentative Gram-negative bacilli or fungus became predominant. Although C. difficile D-1 antigen was observed in 4 cases, its changes had no relationship with characteristics of feces. C. difficile was not detected in any of the cases. MEPM was detected in feces in 4 cases being treatment, in concentrations ranging from 0.35 to 66.0 micrograms/g. Fecal MEPM levels were very low except in 1 case in which beta-lactamase was negative. From these results, effects of MEPM on intestinal flora in children were relatively minor compared to other new beta-lactam drugs. However, a care should be taken to minimize diarrhea and bacterial turnover when a prolonged use of the antibiotic, was practiced because of potential significant effects on intestinal flora.