Effect of hesperidin in vitro on root dentine collagen and demineralization.

OBJECTIVES: Caries progress might be controlled when collagen matrix could be preserved after demineralization. The aim of this pH cycling study was to investigate the effect of hesperidin, a citrus flavonoid antioxidant, on dentine collagen and remineralization in dentine lesion, and compared with that of chlorhexidine. METHODS: The pH cycling was employed on bovine root dentine by demineralization for 14 h, incubation in testing solutions (hesperidin or chlorhexidine) for 2 h and remineralization with bacteria-derived collagenase for 8 h, for 8 days. Calcium release was measured by means of an atomic absorption spectrophotometer, and degraded collagen matrix by collagenase was investigated by assaying hydroxyproline. The lesion depth and mineral loss was evaluated by means of transverse microradiography. RESULTS: The effect of testing solutions had a significant difference on the results of chemical analyses (p<0.0115 for calcium release; p<0.0008 for degradated collagen). The lesion depth and mineral loss were reduced in the lesions where were incubated with hesperidin and chlorhexidine. The remineralization in deep lesions was found when the matrix was incubated in hesperidin, whilst no mineral uptake in deep lesion when incubated in chlorhexidine. CONCLUSION: Hesperidin preserved collagen and inhibited demineralization, and enhanced remineralization even under the fluoride-free condition.

[Pharmacokinetic, bacteriological and clinical studies on cefprozil in pediatric patients].

Cefprozil (CFPZ, BMY-28100), a new oral cephem antibiotic, was studied for its antibacterial activities, absorption and excretion upon administration. Its clinical efficacies were also studied in pediatric patients with infections. A study on antibacterial activities of CFPZ against 11 clinical isolates including 6 species found that its activities against Staphylococcus aureus, alpha-hemolytic Streptococcus, Escherichia coli and Haemophilus influenzae were equal or superior to those of CCL. When CFPZ was given to patients orally at 15 mg/kg, maximum serum concentration was obtained between 1 to 2 hours after administration and urinary excretion rate in the first 6 hours was 33.8 +/- 17.6%. Clinical evaluation was done in a total of 25 patients with various infections. Responses were excellent in 15 cases and good in 10 cases, hence the efficacy rate was 100%. As side effect, soft stool was found in 1 case, and eosinophilia in 2 cases and elevation of GOT and GPT in 1 case were found as abnormal laboratory test results, but none of them was serious. It appears that CFPZ is an effective and safe antibiotic in the field of pediatrics.

[Pharmacokinetics and clinical studies on aztreonam in neonates].

Pharmacokinetic and clinical studies on aztreonam (AZT) were performed in neonates. Serum concentrations and urinary excretion of AZT were determined in 12 neonates with ages between 0 and 7 days (birth weights were between 1,260 and 3,500 g) upon intravenous injection or 1 hour drip intravenous infusion of AZT at 20 mg/kg. Serum concentrations of AZT at 1 hour after i.v. administration were 54.0 +/- 12.5 micrograms/ml, and half-lives were 6.01 +/- 0.70 hours. Serum concentrations of AZT reached their peaks at the end of drip infusion with levels of 42.1 +/- 17.6 micrograms/ml in the d.i.v. group and half-lives were 6.40 +/- 1.88 hours. Urinary recovery rates in the first 12 hours after administration were 28.5 +/- 6.4% for the i.v. group and 32.3 +/- 13.9% for the d.i.v. group. AZT was administered to 12 neonatal patients (2 cases of sepsis, 2 cases of suspected sepsis, 3 cases of pneumonia, 2 cases of urinary tract infection and 3 cases for prophylaxis), and clinical effectiveness, bacteriological efficacy and adverse reactions were evaluated. Clinical efficacies in 9 cases except 3 cases with prophylactic use were excellent in 1 case, good in 5 cases, fair in 1 case, poor in 1 case and unknown in 1 case, thus the efficacy rate was 75%. Bacteriological effects in 3 strains with Gram-negative bacilli were eradicated in 2 strains and unchanged in 1 strain, hence the bacteriological eradication rate was 66.7%. Increased GOT and GPT were observed in 1 cases as abnormal laboratory test results, but the abnormality was not serious.(ABSTRACT TRUNCATED AT 250 WORDS)

[Basic and clinical studies of ceftizoxime suppositories in the pediatric field].

Pharmacokinetic and clinical studies of ceftizoxime suppository (CZX-S) were performed in 10 children with the following results. CZX-S attained a peak serum concentration of 6.85 micrograms/ml 30 minutes after dosing with the drug 5.6 mg/kg (one suppository of CZX-S contains 250 mg of CZX in potency). The mean 6-hour urinary excretion rate in 4 children was 18.9%. The subjects consisted of 8 patients comprising 1 with pharyngitis, 3 with tonsillitis, 1 with gingivitis and 3 with urinary tract infection. The overall effect of CZX-S was "excellent" in 5 patients and "good" in 3, with an effectiveness rate of 100%. No side effects ascribable to CZX-S were encountered in any of the patients. A few patients complained of discomfort after the first or second insertion of the drug. However, the discharge of the suppository was as infrequent as 1.5% of the total 133 insertions. CZX-S is therefore well tolerated for clinical use in children. It is concluded that the unique suppository formulation of CZX-S is useful in the treatment of infections in children with heavy psychophysiologic disorders and in children who cannot take oral drugs because of severe vomiting.