Nucleoside drugs play an essential role in treating major diseases such as tumor and viral infections, and have been widely applied in clinics. However, the effectiveness and application of nucleoside drugs are significantly limited by their intrinsic properties such as low bioavailability, lack of targeting ability, and inability to enter the cells. Nanocarriers can improve the physiological properties of nucleoside drugs by improving drug delivery efficiency and availability, maintaining drug efficacy and system stability, adjusting the binding ability of the carrier and drug molecules, as well as modifying specific molecules to achieve active targeting. Starting from the design strategy of nucleoside drug nanodelivery systems, the design and therapeutic effect of these nanomedicines are described in this review, and the future development directions of nucleoside/nucleotide-loaded nanomedicines are also discussed.
Nanomedicine ; Nucleosides/chemistry* ; Nucleotides ; Nanoparticles/chemistry* ; Drug Delivery Systems ; Drug Carriers

8-hydroxy-2'-deoxyguanosine (8-OHdG) is a sensitive and stable biomarker for evaluating DNA oxidative damage. A rapid and sensitive colloidal gold immunochromatographic strip was developed for 8-OHdG detection by a competitive method. The sample pad (glass cellulose film), bonding pad (glass cellulose film), nitrocellulose film and absorbent pad were pasted on the polyvinyl chloride (PVC) base plate to construct the test strip. Colloidal gold (AuNPs) was prepared by the reduction of chloroauric acid with sodium citrate. 8-OHdG antibody (Ab) was coated on the outer layer of AuNPs to form Ab@AuNPs as a probe. Bovine serum albumin (BSA) and 8-OHdG were conjugated with carbodiimide hydrochloride to prepare an artificial antigen, which was used as the coating antigen of detection line. Goat anti mouse polyclonal antibody IgG was used as the coating antibody of control line. The experimental parameters were optimized including the type of nitrocellulose membrane, the formula of loading solution, and the spraying amount of gold labeled antibody. The results showed that the appropriate nitrocellulose membrane was CN 95. The optimal loading solution included BSA (1%), Tween-20 (3%), sucrose (3%) and NaCl (0.9%). The optimal spraying amount of gold labeled antibody was 4 μL. 8-OHdG can be detected by the strip under visible light, and the level of 8-OHdG in urine can be preliminarily determined by comparing the color intensity of T line and C line. The 8-OHdG concentration in urine was further calculated by the gray value of T line and the threshold of detection was 2.55 μg/L. This colloidal gold immunochromatographic strip is simple, rapid and specific for detecting 8-OHdG in human urine to preliminarily evaluate the human status.
8-Hydroxy-2'-Deoxyguanosine ; Animals ; Antibodies, Monoclonal ; Gold ; Gold Colloid/chemistry* ; Metal Nanoparticles ; Mice ; Sensitivity and Specificity

Objective To investigate the safety and short-term effectiveness of the hybrid operation for the treatment of intracranial complex ruptured aneurysms.Methods From December 2014 to March 2017,14 consecutive patients with complex ruptured aneurysm treated with hybrid operation at the Department of Neurosurgery,Nanfang Hospital,Southern Medical University were enrolled retrospectively,including 13 with acute spontaneous aneurismal subarachnoid hemorrhage and 1 with hemorrhage in the recurrent aneurysm embolization.Twelve aneurysms were treated with shape clipping.Digital subtraction angiography (DSA) was used to evaluate the clipping effect of aneurysms.Two patients with aneurysm were treated with extracranial-intracranial (EC-IC) bypass and aneurysm trapping.Endovascular balloon occlusion for trapping aneurysms was performed after DSA evaluation of the patency of bridge vessel.Results Of the 14 patients,11 were treated with emergency hybrid operation after angiography,2 were treated with elective surgery,and 1 with emergency surgery for rescue because of bleeding during embolization.DSA revealed that the aneurysm clips in 3 of 12 patients needed to be adjusted,including 2 parent artery stenosis and 1 with incomplete clipping.After adjustment,the clipping was satisfactory.In intracranial and extracranial bypass surgery,angiography revealed that the blood vessels were patent.Trapping of the aneurysms was performed in the one-stage operation.One patient discharged voluntarily after procedure because of serious vasospasm.Onepatient had perfusion pressure breakthrough after surgery and received hematoma evacuation and decompression.The Glasgow outcome scale (GOS) score was 3 at discharge.Other patients had no new neurological dysfunction after operation.Thirteen patients were followed up for 3-24 months after operation.There were no new neurological dysfunction,including GOS 5 in 8 cases and 4 in 5 cases.Six patients underwent DSA examination,in 4 of them the aneurysm clipping did not show aneurysm recurrence,and the parent arteries were patent.Two patients treated with vascular bypass.There were no recurrence of aneurysms,and the parent arteries and anastomotic vessels were patent.Conclusion After preliminary observation,using hybrid operation for the treatment of complicated intracranial ruptured aneurysms was safe and effective.

Objective To investigate the impacts of S-ademetionine (SAM) on cell cycles,apoptosis and invasive capacity of gastric cancer cell lines,and its effects on methylation and expressions of c-myc and uPA.Methods MKN-28,SGC-7901 and MKN-45 cells were treated with gradient concentrations of SAM(0,2 and 4 mmol/L) for 72 hours.The changes of cell cycles and apoptosis were detected by flow eytometry,and invasion was detected by transwell assay.The expressions and methylations of c-myc and uPA were examined by RT-PCR and MSP,respectively.Results The cell apoptosis significantly increased and cell invasive capacity was restrained in three cell lines with increase of SAM concentration (all P values<0.01).In SGC-7901,the cell percentage of G0/G1 phase significantly increased [(74.53±2.49)% vs.(56.67±1.18)%,P<0.053,whereas the cell proliferation index (PI) decreased [(25.50±2.46)% vs.(43.33±1.18)%,P<0.05] in comparison with controls.The expressions of c-myc and uPA mRNA in SGC-7901,uPA mRNA in MKN-45 and in 4 mmol/L SAM treated MKN-28 significantly decreased.The methylations of c-myc gene in SGC-7901 and uPA gene in three cell lines were reversed after treated with SAM.Conclusions SAM reduces expressions of c-myc and uPA by reversing the methylations of c-myc in SGC-7901 and uPA in all three cell lines.However SAM,as methyl donor,can restrain the development and progression of tumor when hypomethylation widely presents in cancer.