Evaluation of the Efficacy and Tolerability of Oral Ciprofloxacin used in the Comprehensive Treatment of External Bacterial Otitis: An Observational Prospective Study

Tunable ciprofloxacin delivery through personalized electrospun patches for tympanic membrane perforations

Approximately 740 million symptomatic patients are affected by otitis media every year. Being an inflammatory disease affecting the middle ear, it is one of the primary causes of tympanic membrane (TM) perforations, often resulting in impaired hearing abilities. Antibiotic therapy using broad-spectrum fluoroquinolones, such as ciprofloxacin (CIP), is frequently employed and considered the optimal route to treat otitis media. However, patients often get exposed to high dosages to compensate for the low drug concentration reaching the affected site. Therefore, this study aims to integrate tissue engineering with drug delivery strategies to create biomimetic scaffolds promoting TM regeneration while facilitating a localized release of CIP. Distinct electrospinning (ES) modalities were designed in this regard either by blending CIP into the polymer ES solution or by incorporating nanoparticles-based co-ES/electrospraying. The combination of these modalities was investigated as well. A broad range of release kinetic profiles was achieved from the fabricated scaffolds, thereby offering a wide spectrum of antibiotic concentrations that could serve patients with diverse therapeutic needs. Furthermore, the incorporation of CIP into the TM patches demonstrated a favorable influence on their resultant mechanical properties. Biological studies performed with human mesenchymal stromal cells confirmed the absence of any cytotoxic or anti-proliferative effects from the released antibiotic. Finally, antibacterial assays validated the efficacy of CIP-loaded scaffolds in suppressing bacterial infections, highlighting their promising relevance for TM applications.

Molecular epidemiology and antimicrobial susceptibility of human Clostridium difficile isolates from a single institution in Northern China

Because the epidemiology of Clostridium difficile infection (CDI) is region-specific, the present study was undertaken to examine the epidemiology of C difficile outbreaks in Beijing, China.Eighty nonduplicate isolates were collected from March, 2016 to December, 2016. The molecular type and phylogenetic analysis were evaluated by multilocus sequence typing (MLST). The minimum inhibitory concentrations (MICs) for 11 antibiotics and the resistance mechanisms were investigated.Sixty-five toxigenic strains (81.25%), including 22 tcdABCDT strains (27.5%) and 43 tcdABCDT strains (53.75%), and also 15 nontoxigenic strains (tcdABCDT; 18.75%) were detected. MLST identified 21 different sequence types (STs), including 2 novel types (ST409 and ST416). All isolates were susceptible to metronidazole, vancomycin, fidaxomicin, piperacillin/tazobactam, and meropenem, and all were effectively inhibited by emodin (MICs 4-8 μg/mL). The resistance rates to rifaximin, ceftriaxone, clindamycin, erythromycin, and ciprofloxacin were 8.75%, 51.25%, 96.25%, 81.25%, and 96.25%, respectively; 81.25% (65/80) of isolates were multidrug-resistant. Amino acid mutations in GyrA and/or GyrB conferred quinolone resistance. One novel amino acid substitution, F86Y in GyrA, was found in 1 CIP-intermediate strain. The erm(B) gene played a key role in mediating macrolide-lincosamide-streptogramin B (MLSB) resistance. Erm(G) was also found in erm(B)-negative strains that were resistant to both erythromycin and clindamycin. RpoB mutations were associated with rifampin resistance, and 2 new amino mutations were identified in 1 intermediate strain (E573A and E603N).Regional diversity and gene heterogeneity exist in both the ST type and resistant patterns of clinical C difficile isolates in Northern China.