Recent reports indicate that nadifloxacin is an effective therapy for acne vulgaris and has a mechanism of action similar to that of the tetracyclines which act directly as antioxidants against infiltrated neutrophils. The effects of nadifloxacin on neutrophil functions, including the generation of reactive oxygen species, chemotaxis and phagocytosis were investigated. Nadifloxacin reduced the numbers of superoxide radical anions (O2-) and hydroxyl radicals (OH.) generated by neutrophils. The drug did not, however, significantly inhibit neutrophil chemotaxis and phagocytosis nor did it decrease the levels generated in a cell-free, xanthine-xanthine oxidase system. These results indicate that the clinical effectiveness of nadifloxacin may be partly due to its inhibitory action on the generation of O2- and OH. by neutrophils leading to a reduction in oxidative tissue injury.

Anti-Infective Agents↗

PubMedDate not supplied

Sensitivity of Staphylococcus aureus, isolated from skin infections in 1994, to 19 antimicrobial agents.

The most common pathogen causing skin infections is Staphylococcus aureus and the incidence of multiply resistant strains of S. aureus has been increasing. The in vitro susceptibility of 130 isolates of S. aureus to 19 antimicrobial agents: ampicillin (ABPC), methicillin, cefaclor, cefpodoxime proxetil, gentamicin, erythromycin, clindamycin, minocycline, vancomycin, fusidic acid, norfloxacin, ofloxacin, enoxacin, ciprofloxacin, lomefloxacin, tosufloxacin, sparfloxacin, nadifloxacin and grepafloxacin, was evaluated by agar dilution tests. The S. aureus isolates were isolated from 130 patients with skin infections in 1994. The proportion of methicillin-resistant S. aureus isolates among the strains isolated was 19.2%. The concentration needed to inhibit 50% of the isolates was 3.13 mg/ml or less for all of the drugs, but the concentration needed to inhibit 90% of isolates was over 12.5 micrograms/ml, except in the cases of minocycline, vancomycin, fusidic acid, tosufloxacin and nadifloxacin. Tosufloxacin and nadifloxacin had the lowest minimum inhibitory concentrations. None of the S. aureus strains was resistant to nadifloxacin.

Anti-Bacterial Agents↗

PubMedDate not supplied

Activity of nadifloxacin against methicillin-resistant Staphylococcus aureus isolated from skin infections: comparative study with seven other fluoroquinolones.

The in vitro susceptibility of methicillin-resistant Staphylococcus aureus (MRSA) to nadifloxacin and seven other fluoroquinolones (norfloxacin, ofloxacin, enoxacin, ciprofloxacin, lomefloxacin, tosufloxacin and sparfloxacin) was evaluated. The MRSA isolates were isolated from 114 skin infections between 1991 and 1994. Nadifloxacin exhibited the lowest minimum inhibitory concentration and there were no MRSA isolates resistant to nadifloxacin, while there were some resistant to all of the other seven fluoroquinolones. The minimum concentrations of these drugs needed to cause 50% inhibition of the isolates increased dramatically from 1991 to 1992, but has hardly changed since 1992.

Anti-Infective Agents↗

PubMedDate not supplied

The effect of roxithromycin on the generation of reactive oxygen species in vitro.

The effect of roxithromycin (ROM), a new oral semi-synthetic macrolide, on the generation of reactive oxygen species (ROS), using human neutrophils and a cell-free, xanthine-xanthine oxidase system was examined. The species investigated were the superoxide radical anion (O2-), hydrogen peroxide (H2O2), and the hydroxyl radical (OH.). ROM effectively inhibited the generation of O2-, H2O2 and OH. by human neutrophils. On the other hand, the drug did not markedly affect the ROS levels generated in the xanthine-xanthine oxidase system. The present study indicates that ROM may exert an anti-inflammatory action by inhibiting neutrophil oxygen radical generation at the sites of inflammation.

Anti-Bacterial Agents↗

PubMedDate not supplied

Clinical evaluation of roxithromycin in patients with acne.

On the basis of reports that erythromycin is effective in the treatment of acne, we investigated whether roxithromycin (ROM), a new derivative of erythromycin, might also be effective in treating acne. Roxithromycin was administered to 30 patients with acne for 8 weeks. General improvement was assessed 8 weeks after the initiation of the therapy with a six-graded scale as follows; 1: good improvement, 2: moderate improvement, 3: slight improvement, 4: no change, 5: worsening, and 6: no assessment. The percentage of good or moderate improvement was 73.3%, and that of good improvement alone was 20.0%. Our results suggest that ROM is effective in the treatment of acne.

Acne Vulgaris↗

PubMedDate not supplied

Sensitivity of Propionibacterium acnes isolated from acne patients: comparative study of antimicrobial agents.

The antimicrobial susceptibility of Propionibacterium acnes isolated before and after treatment of acne patients was measured. The four female and three male acne patients were treated with an oral acne medication, roxithromycin or minocycline, and/or a topical acne medication, nadifloxacin cream or clindamycin hydrochloride lotion for 1-8 weeks. The isolated strains were tested for their susceptibility to the antimicrobial action of: nadifloxacin, ofloxacin, erythromycin, clindamycin hydrochloride, tetracycline hydrochloride, minocycline, doxycycline, ampicillin, cephalexin and gentamycin. No resistant strains of P. acnes were observed.

Acne Vulgaris↗

PubMedDate not supplied

Sensitivity to antibacterials of Staphylococcus aureus isolated from different types of skin infections.

We examined the antibacterial susceptibility of Staphylococcus aureus isolated from several types of skin infections, which were classified into four groups: (i) impetigo, (ii) folliculitis, (iii) atopic dermatitis and eczema and (iv) ulcers and decubitus. The 50% minimal inhibitory concentration (MIC50) of the antibacterial agents was 3.13 micrograms/ml or lower, except that of gentamicin with isolates from the impetigo groups (25 micrograms/ml). The MIC90 of gentamicin was 50 micrograms/ml or more for isolates from all four groups. The isolates from the ulcers and decubitus group showed multiple resistance against antibacterial agents. The frequency of methicillin-resistant S. aureus was low, but was highest, at 25%, in the isolates from the ulcers and decubitus group. Few isolates from the atopic dermatitis and eczema group were resistant, and there was little difference in antibacterial resistance between isolates from atopic dermatitis and eczema.

Anti-Bacterial Agents↗