BACKGROUND:With unique structure and physicochemical property, carbon nanotubes have promising application prospects in the fields of drug delivery, biosensor and biomaterials. However, carbon nanotubes are highly hydrophobic and trend to aggregate, and thus carbon nanotubes are hard to be dispersed in solution. Furthermore, carbon nanotubes induce blood coagulation and have cytotoxicity, which greatly limit the application of carbon nanotubes. OBJECTIVE:To prepare heparinized single-wal ed carbon nanotubes and to study the effects of heparin-immobilization on the water solubility, stability as wel as biocompatibility of carbon nanotubes. METHODS:By the method of covalent grafting, heparinized single-wal ed carbon nanotubes was fabricated and characterized by Fourier transform infrared spectroscopy and carbazole assay. Transmission electron microscopy was used to investigate the dispersing performance and suspension stability of heparinized single-wal ed carbon nanotubes in aqueous solution. Anti-Xa activity and activated partial thromboplastin time assays were used to measure the anticoagulation activity of heparinized single-wal ed carbon nanotubes. MTT assay was used to evaluate the cytocompatibility of heparinized single-wal ed carbon nanotubes.
RESULTS AND CONCLUSION:Heparin was covalently linked to the surface of single-wal ed carbon nanotubes successful y. The amount of heparin on single-wal ed carbon nanotubes was measured to be 257.53 mg/g. Heparinized single-wal ed carbon nanotubes were wel dispersed and stable in an aqueous solution without aggregation. The anti-Xa activity of heparinized single-wal ed carbon nanotubes was measured to be 36.53 U/mg, suggesting a significant anticoagulant activity. Further study of activated partial thromboplastin time assay found that the anticoagulant effect of heparinized single-wal ed carbon nanotubes could be prolonged. MTT assay revealed that heparinized single-wal ed carbon nanotubes had no cytotoxicity and showed good cytocompatibility. Taken together, the immobilization of heparin on single-wal ed carbon nanotubes wil not only improve its solubility and stability in water, but also endow it with excellent biocompatibility.

To evaluate the safety and efficacy of neoadjuvant radiohormonal therapy for oligometastatic prostate cancer (OMPC), we conducted a 3 + 3 dose escalation, prospective, phase I/II, single-arm clinical trial (CHiCTR1900025743), in which long-term neoadjuvant androgen deprivation was adopted 1 month before radiotherapy, comprising intensity modulated radiotherapy to the pelvis, and stereotactic body radiation therapy to all extra-pelvic bone metastases for 4-7 weeks, at 39.6, 45, 50.4, and 54 Gy. Robotic-assisted radical prostatectomy was performed after 5-14 weeks. The primary outcome was treatment-related toxicities and adverse events; secondary outcomes were radiological treatment response, positive surgical margin (pSM), postoperative prostate-specific antigen (PSA), pathological down-grading and tumor regression grade, and survival parameters. Twelve patients were recruited from March 2019 to February 2020, aging 66.2 years in average (range, 52-80). Median baseline PSA was 62.0 ng/mL. All underwent RARP successfully without open conversions. Ten patients recorded pathological tumor down-staging (83.3%), and 5 (41.7%) with cN1 recorded negative regional lymph nodes on final pathology. 66.7% (8/12) recorded tumor regression grading (TRG) -I and 25% (3/12) recorded TRG-II. Median follow-up was 16.5 months. Mean radiological progression-free survival (RPFS) was 21.3 months, with 2-year RPFS of 83.3%. In all, neoadjuvant radiohormonal therapy is well tolerated for oligometastatic prostate cancer.
Male ; Humans ; Prostatic Neoplasms/radiotherapy* ; Prostate-Specific Antigen/therapeutic use* ; Neoadjuvant Therapy ; Androgen Antagonists/therapeutic use* ; Prospective Studies