Study of metal/carbon composite materials applied in medical treatments
| Autor: | Ming-Chien Hung, 洪銘謙 |
|---|---|
| Rok vydání: | 2014 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 102 Hemorrhagic cystitis (HC) is a diffuse inflammatory condition of a urinary bladder cause by an infectious or noninfectious etiology resulting in bleeding from the bladder mucosa. We aimed to explore a new strategy for treating HC. Bacteria can induce urinary tract infection and even cause HC, and lipopolysaccharide (LPS), which is a component of the cell wall of gram-negative bacteria, is believed to be the cause for HC. Therefore, the availability of a method to remove LPS from the bladder is the key issue in treating HC. Active carbon fiber (AC) materials exhibit strong adsorption towards toxins. Therefore, AC suspension was prepared and instilled into a rat’s bladder to bind LPS, which was then removed through the urinary tract. Finally, the conditions of bladder infection and hemorrhage were improved. To confirm the therapeutic results of this method, in vitro experiments will be conducted to verify the biocompatibility of AC, and in vivo experiments will be conducted to evaluate the treatment effect of AC in rats. An in vitro study showed that AC exhibited a remarkable LPS adsorption capability (20.24 EU/mg for 60 min) and good biocompatibility in SV-HUC-1 cell line via morphology observation using field-emission scanning electron microscopy and MTS assay. In an in vivo assay conducted in rats, 3 groups (n = 10 in each group), control (pyrogen-free saline), LPS, and AC, were formed. The LPS and AC groups were pretreated with protamine sulfate (10 mg/mL), and E. coli LPS (5 mg/kg) was then administered to both groups to induce cystitis. Subsequently, the AC group received 0.4 mg/kg AC suspension. Twenty-four hours after the administration, histologic analysis revealed an increase in both urinary bladder weight (i.e., edema) and vascular congestion in the LPS group. In contrast, the AC group showed a significant reduction in the degree of edema, inflammatory cell infiltration, and hemorrhage (p < 0.05), demonstrating the potential of AC for use as an auxiliary agent for cystitis amelioration. Acrolein (ACR) is a byproduct of the chemotherapeutic drug CYP, and it is the major substance that induces hemorrhage. In the present study, we investigated the use of zinc oxide (ZnO) and carbon fiber (CF) composites as catalysts to remove ACR by photodegradation. ZnO/CF specimens were prepared by a sol–gel method followed by an annealing treatment conducted separately at 200, 300, and 400 °C in air. In the case of annealing treatment at 200 °C (CZ200), a continuous and porous ZnO film was formed on the CF surface. Field-emission scanning electron microscopy and physisorption analysis indicated the large specific surface area of the composite material. Further, X-ray diffraction analysis and photoluminescence spectroscopy showed that the ZnO film was amorphous and exhibited a broad emission spectrum. An ultraviolet (UV) radiation-based degradation system and methylene blue (MB) solution were used to evaluate the feasibility of using the composite as a photodegradation catalyst. CZ200 exhibited the highest MB photodegradation rate (95%) among all specimens. Finally, the photodegradation of ACR (75 ppm) under a 4-W UV light was investigated by using an untreated CF sample, active carbon fiber (ACF) fabric sample, and CZ200 specimen. CZ200 (45%) exhibited a higher ACR degradation rate than CF (8%) and ACF (28%) did, as determined by high-performance liquid chromatography. These results demonstrated that ZnO/CF composites could be used for the reduction of ACR by photodegradation. This study developed a new strategy for treating HC by using a type of new carbon material and demonstrated the great potential of the method for use in the prevention of infectious or noninfectious HC. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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