RESUMEN
In this study, poly (trimethylene carbonate) (PTMC) with excellent biocompatibility was synthesized via ring-opening of TMC to prepare the Ciprofloxacin-loaded PTMC implants, and antibacterial effects in vitro or in vivo of the resulting implants were investigated to evaluate the potential for treating chronic osteomyelitis. The in vitro results showed the Ciprofloxacin-loaded PTMC implants could sustain release ciprofloxacin at a release amount of about 90 µg/d for 28 days and possessed excellent antibacterial effect, as evidenced by the smaller size of the antibacterial ring of 32.6 ± 0.64 mm and the biofilm inhibition of 60% after 28 days of release. The in vivo results showed that after 28 days of treatment, the body weight and the white blood cell counts of chronic-osteomyelitis-model rats in the treatment group reached 381.6 ± 16.8 g and (7.86 ± 0.91) ×109/L, respectively, returning to normal rapidly compared with the control and blank group, indicating the remarkable antibacterial effect of the Ciprofloxacin-loaded PTMC implants. X-ray images and HE staining results also confirmed that most of the proximal and middle parts of the tibia returned to typical structures and new and trabecular bone had been formed for the rats in the treatment group, and no inflammatory cells were found as compared to the control and blank groups, after 28 days of treatment. The significant lower number of colonies of (9.92 ± 1.56) × 10 CFU/g in the treatment group also suggests that the Ciprofloxacin-loaded PTMC implants achieve a practical antibacterial effect through a local application.
RESUMEN
Mono- and bimetallic Ni-based catalysts were prepared by screening 6 supports and 14 secondary metals for reductive amination of 5-hydroxymethylfurfural (5-HMF) into 2,5-bis(aminomethyl)furan (BAMF), among which γ-Al2 O3 and Mn were the best candidates. By further optimization of the reaction conditions at 0.4â g catalyst loading for 0.5â g substrate of 5-HMF and 160 °C of reaction temperature, 10Ni/γ-Al2 O3 and 10NiMn(4 : 1)/γ-Al2 O3 achieved the highest BAMF yields of 86.3 and 82.1 %, respectively. Although the BAMF yield values were comparable with that over Raney Ni, the turnover frequencies based on the initial BAMF yield and unit weight of Ni for 10NiMn(4 : 1)/γ-Al2 O3 , 10Ni/γ-Al2 O3 , and Raney Ni were calculated as 0.41, 0.09, and 0.04â h-1 , respectively. X-ray diffraction, transmission electron microscopy, and X-ray photoelectron spectroscopy showed that the existence of MnOx well dispersed on the γ-Al2 O3 support and its electron transfer effect with Ni particles on the surface of the support contributed to the high efficiency and better recyclability for the five-time reused 10NiMn(4 : 1)/γ-Al2 O3 catalyst.