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// Yuan-Yun Tseng 1, 2 , Chen-Hsing Su 3 , Shun-Tai Yang 1, 2 , Yin-Chen Huang 4 , Wei-Hwa Lee 5 , Yi-Chuan Wang 6 , Shou-Cheng Liu 6 , Shih-Jung Liu 6, 7 1 Division of Neurosurgery, Department of Surgery, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan 2 Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan 3 Department of Neurosurgery, Chung Shan Medical University Hospital, Taichung, Taiwan 4 Department of Neurosurgery, Chang Gung Memorial Hospital-Chiayi, Chang Gung University College of Medicine, Tao-Yuan, Taiwan 5 Department of Pathology, Shuang Ho Hospital, Taipei Medical University, Taipei, Taiwan 6 Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan 7 Department of Orthopedics, Chang Gung Memorial Hospital, Tao-Yuan, Taiwan Correspondence to: Shih-Jung Liu, email: shihjung@mail.cgu.edu.tw Keywords: glioblastoma multiforme (GBM), chemotherapy, targeted therapy, nanofiber, antiangiogenesis Received: March 06, 2016 Accepted: June 27, 2016 Published: August 1, 2016 ABSTRACT Glioblastoma multiforme (GBM), the most prevalent and malignant form of a primary brain tumour, is resistant to chemotherapy. In this study, we concurrently loaded three chemotherapeutic agents [bis-chloroethylnitrosourea, irinotecan, and cisplatin; BIC] into 50:50 poly[(d,l)-lactide-co-glycolide] (PLGA) nanofibres and an antiangiogenic agent (combretastatin) into 75:25 PLGA nanofibres [BIC and combretastatin (BICC)/PLGA]. The BICC/PLGA nanofibrous membranes were surgically implanted onto the brain surfaces of healthy rats for conducting pharmacodynamic studies and onto C6 glioma-bearing rats for estimating the therapeutic efficacy. The chemotherapeutic agents were rapidly released from the 50:50 PLGA nanofibres after implantation, followed by the release of combretastatin (approximately 2 weeks later) from the 75:25 PLGA nanofibres. All drug concentrations remained higher in brain tissues than in the blood for more than 8 weeks. The experimental results, including attenuated malignancy, retarded tumour growth, and prolonged survival in tumour-bearing rats, demonstrated the efficacy of the BICC/PLGA nanofibrous membranes. Furthermore, the efficacy of BIC/PLGA and BICC/PLGA nanofibrous membranes was compared. The BICC/PLGA nanofibrous membranes more efficiently retarded the tumour growth and attenuated the malignancy of C6 glioma-bearing rats. Moreover, the addition of combretastatin did not significantly change the drug release behaviour of the BIC/PLGA nanofibrous membranes. The present advanced and novel interstitial chemotherapy and targeted treatment provide a potential strategy and regimen for treating GBM.

The purpose of this study is to develop biodegradable drug-eluting pellets to provide a sustainable delivery of cisplatin intrapleurally. Poly(d,l)-lactide-co-glycolide (PLGA) (LA:GA = 50:50) copolymer and cisplatin were mixed, compressed, and sintered to construct biodegradable pellets and placed in phosphate-buffered saline to test the characteristics of in vitro release. In vivo, equal amounts of cisplatin (10 mg/kg) were introduced into rabbit pleural cavities either by free form (Gr1) or pellets form (Gr2). Cisplatin concentrations in the collected pleural effusion and blood were measured and compared by repeated measurement ANOVA. In vitro, approximately 5% of the cisplatin was released in the first day while the rest was gradually released in the following 50 days. In vivo, the cisplatin level in the pleural fluid was equally high during the first 2 days but dropped quickly in Gr1 while remaining high in Gr2 for 18 days, the difference was statistically significant (P < 0.001) In contrast, the plasma cisplatin level was 10 times significantly higher in Gr1 than in Gr2 (P < 0.001), which resulted in two early deaths of rabbits. Thus we concluded that our biodegradable pellets could achieve high and steady cisplatin release in the pleural cavity. This novel drug delivery system may have the potential to serve as an adjuvant treatment for malignant pleural lesion.

Yuan-Yun Tseng,1,2 Tao-Chieh Yang,3 Yi-Chuan Wang,4 Wei-Hwa Lee,5 Tzu-Min Chang,4 Yi-Chuan Kau,6 Shih-Jung Liu4,7 1Division of Neurosurgery, Department of Surgery, Shuang Ho Hospital, 2Department of Surgery, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 3Department of Neurosurgery, Asia University Hospital, Taichung, 4Department of Mechanical Engineering, Chang Gung University, Taoyuan, 5Department of Pathology, Shuang Ho Hospital, Taipei Medical University, Taipei, 6Department of Anesthesiology, 7Department of Orthopedic Surgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan Abstract: Glioblastoma is the most frequent and devastating primary brain tumor. Surgery followed by radiotherapy with concomitant and adjuvant chemotherapy is the standard of care for patients with glioblastoma. Chemotherapy is ineffective, because of the low therapeutic levels of pharmaceuticals in tumor tissues and the well-known tumor-cell resistance to chemotherapy. Therefore, we developed bilayered poly(d,l)-lactide-co-glycolide nanofibrous membranes that enabled the sequential and sustained release of chemotherapeutic and antiangiogenic agents by employing an electrospinning technique. The release characteristics of embedded drugs were determined by employing an in vitro elution technique and high-performance liquid chromato­graphy. The experimental results showed that the fabricated nanofibers showed a sequential drug-eluting behavior, with the release of high drug levels of chemotherapeutic carmustine, irinotecan, and cisplatin from day3, followed by the release of high concentrations of the antiangiogenic combretastatin from day21. Biodegradable multidrug-eluting nanofibrous membranes were then dispersed into the cerebral cavity of rats by craniectomy, and the in vivo release characteristics of the pharmaceuticals from the membranes were investigated. The results suggested that the nanofibrous membranes released high concentrations of pharmaceuticals for more than 8weeks in the cerebral parenchyma of rats. The result of histological analysis demonstrated developmental atrophy of brains with no inflammation. Biodegradable nanofibrous membranes can be manufactured for long-term sequential transport of different chemotherapeutic and antiangiogenic agents in the brain, which can potentially improve the treatment of glioblastoma multiforme and prevent toxic effects due to systemic administration. Keywords: nanofibrous membrane, poly(d,l)-lactide-co-glycolide (PLGA), glioblastoma multiforme (GBM), chemotherapy, targeted therapy, antiangiogenesis

Background Self-expandable metallic stents (SEMSs) are effective in the palliation of malignant airway obstruction. Tumor ingrowth, however, frequently occurs because of a shortage of effective local therapy. Additionally, SEMSs are frequently associated with problems of fracture, migration, and difficult removals. Our goal was to develop a novel bioabsorbable stent with cisplatin elution to circumvent such problems. Methods Biodegradable stents made of polycaprolactone were fabricated by a laboratory-made, microinjection molding machine. In vitro mechanical strength of the stents was compared with the strength of Ultraflex SEMSs. Polylactide-polyglycolide copolymer and cisplatin were coated onto the surfaces of the stents. Elution method and high-performance liquid chromatography (HPLC) analysis were used to examine the in vitro cisplatin release characteristics. In vivo, the stents were surgically implanted into the cervical trachea of 15 New Zealand white rabbits. Bronchoscopic examination was performed weekly (1 to approximately 5 weeks) before killing. Cisplatin concentrations in trachea, lung, and blood were analyzed by HPLC. Histologic examination was also performed. Results The biodegradable stent exhibited mechanical strength comparable to the strength of Ultraflex SEMSs and provided a steady release of cisplatin for > 4 weeks in vitro. The in vivo study showed sustained cisplatin levels in rabbit trachea for > 5 weeks with a minimum drug level in blood. Histologic examination showed an intact ciliated epithelium and marked leukocyte infiltration in the submucosa of the stented area. Conclusions Our study demonstrated that the biodegradable stents provided physical properties comparable to the properties of SEMSs and a sustained release of cisplatin for > 5 weeks, which showed great potential in the treatment of malignant airway obstruction.

Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor, and the prognosis of patients afflicted with GBM has been dismal, exhibiting progressive neurologic impairment and imminent death. Even with the most active regimens currently available, chemotherapy achieves only modest improvement in the overall survival. New chemotherapeutic agents and novel approaches to therapy are required for improving clinical outcomes. In this study, we used an electrospinning technique and developed biodegradable poly[(d,l)-lactide-co-glycolide] nanofibrous membranes that facilitated a sustained release of carmustine (or bis-chloroethylnitrosourea, BCNU), irinotecan, and cisplatin. An elution method and a high-performance liquid chromatography assay were employed to characterize the in vitro and in vivo release behaviors of pharmaceuticals from the nanofibrous membranes. The experimental results showed that the biodegradable, nanofibrous membranes released high concentrations of BCNU, irinotecan, and cisplatin for more than 8 weeks in the cerebral cavity of rats. A histological examination revealed progressive atrophy of the brain tissues without inflammatory reactions. Biodegradable drug-eluting nanofibrous membranes may facilitate sustained delivery of various and concurrent chemotherapeutic agents in the cerebral cavity, enhancing the therapeutic efficacy of GBM treatment and preventing toxic effects resulting from the systemic administration of chemotherapeutic agents.

Kuo-Sheng Liu,1 Cheng-Hung Lee,2 Yi-Chuan Wang,3 Shih-Jung Liu3 1Department of Thoracic and Cardiovascular Surgery, Chang Gung Memorial Hospital, Linkou, Taiwan; 2Division ofCardiology, Department of Internal Medicine, Chang Gung Memorial Hospital, Linkou, Taiwan; 3Department of Mechanical Engineering, Chang Gung University, Tao-Yuan, Taiwan Abstract: This study describes novel biodegradable, drug-eluting nanofiber-loaded vascular prosthetic grafts that provide local and sustained delivery of vancomycin to surrounding tissues. Biodegradable nanofibers were prepared by first dissolving poly(D,L)-lactide-co-glycolide and vancomycin in 1,1,1,3,3,3-hexafluoro-2-propanol. The solution was then electrospun into nanofibers onto the surface of vascular prostheses. The in vitro release rates of the pharmaceutical from the nanofiber-loaded prostheses was characterized using an elution method and a high-performance liquid chromatography assay. Experimental results indicated that the drug-eluting prosthetic grafts released high concentrations of vancomycin in vitro (well above the minimum inhibitory concentration) for more than 30 days. In addition, the in vivo release behavior of the drug-eluting grafts implanted in the subcutaneous pocket of rabbits was also documented. The drug-eluting grafts developed in this work have potential applications in assisting the treatment of vascular prosthesis infection and resisting reinfection when an infected graft is to be exchanged. Keywords: drug-eluting prosthetic graft, vascular prosthesis infection, release characteristics

The incidence of postoperative central nervous system infection (PCNSI) is higher than 5%–7%. Successful management of PCNSI requires a combined therapy of surgical debridement and long-term antibiotic treatment. In this study, Duraform soaked in a prepared bacterial solution was placed on the brain surface of rats to induce PCNSI. Virgin poly[(d,l)-lactide-co-glycolide] (PLGA) nanofibrous membranes (vehicle-control group) and vancomycin-eluting PLGA membranes (vancomycin-nanofibres group) were implanted. The wound conditions were observed and serial brain MRI and pathology examinations were performed regularly. PCNSI was consistently induced in a single, simple step. In the vehicle-control group, most rats died within 1 week, and the survival rate was low (odds ratio = 0.0357, 95% confidence interval = 0.0057–0.2254). The wounds and affected cerebral tissues necrosed with purulence and increased in mass from the resulting PCNSI volumes. Initially, the mean PCNSI volumes showed no significant difference between the two groups. The PCNSI volume in the rats in the vancomycin-nanofibres group significantly decreased (P < 0.01), and the wound appearance was excellent. Pathologic examinations revealed that the necrosis and leukocyte infiltration area decreased considerably. The experimental results suggest that vancomycin-eluting PLGA nanofibres are favourable candidates for treating PCNSI after surgical debridement.

Yin-Kai Chao,1 Cheng-Hung Lee,2 Kuo-Sheng Liu,1 Yi-Chuan Wang,3 Chih-Wei Wang,4 Shih-Jung Liu3 1Department of Thoracic and Cardiovascular Surgery, Chang Gung Memorial Hospital-Linkou, College of Medicine, Chang Gung University, Taoyuan, Taiwan; 2Division of Cardiology, Department of Internal Medicine, Chang Gung Memorial Hospital-Linkou, College of Medicine, Chang Gung University, Taoyuan, Taiwan; 3Department of Mechanical Engineering, Chang Gung University, Taoyuan, Taiwan; 4Department of Pathology, Chang Gung Memorial Hospital-Linkou, College of Medicine, Chang Gung University, Taoyuan, Taiwan Background: Inadequate intrapleural drug concentrations caused by poor penetration of systemic antibiotics into the pleural cavity is a major cause of treatment failure in empyema. Herein, we describe a novel antibiotic-eluting pigtail catheter coated with electrospun nanofibers used for the sustained release of bactericidal concentrations of penicillin in the pleural space.Methods: Electrospun nanofibers prepared using polylactide-polyglycolide copolymer and penicillin G sodium dissolved in 1,1,1,3,3,3-hexafluoro-2-propanol were used to coat the surface of an Fr6 pigtail catheter. The in vitro patterns of drug release were tested by placing the catheter in phosphate-buffered saline. In vivo studies were performed using rabbits treated with penicillin either intrapleurally (Group 1, 20 mg delivered through the catheter) or systemically (Group 2, intramuscular injection, 10 mg/kg). Penicillin concentrations in the serum and pleural fluid were then measured and compared.Results: In vitro studies revealed a burst release of penicillin (10% of the total dose) occurring in the first 24 hours, followed by a sustained release in the subsequent 30 days. Intrapleural drug levels were significantly higher in Group 1 than in Group 2 (P