Yi Wan

Publications (3)4.86 Total impact

• Article: [Preparation and biological characteristics of a new doxorubicin-gelatin-microspheres for hepatic artery embolization].

  Yi Wan, Yu Ma, Xiao-li Chen, Li-geng Duan, Dong-hui Luo, Chuan-qin Xia
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  ABSTRACT: To prepare a new doxorubicin-gelatin-microspheres (DR-GMs) suitable for hepatic artery chemoembolization. Oxidized dextran and glutaraldehyde were used respectively as crosslinking agent for preparing DR-GMs. Orthogonal design was employed to optimize the preparation of the oxidized dextran cross-linked GMs. The morphology, swelling, and in vitro and in vivo degrading were compared between the two groups of microspheres, both with 60% degree of cross-linking. The granulometers of both groups of microspheres fitted for hepatic artery embolization. The roundness of the microspheres (observed with scanning electron microscope) crosslinked by oxidized-dextran was better than those crosslinked by glutaraldehyde. The microspheres crosslinked by oxidized-dextran had an average diameter of (78.2 +/- 8.1) microm, and a narrow size distribution (76.4 +/- 3.2)%, which ranged from 50 to 125 microm. The drug content rate and encapsulation rate of the microspheres crosslinked by oxidized-dextran were (87.5 +/- 0.9)% and (12.2 +/- 1.1)% respectively, higher than those crosslinked by glutaraldehyde (P < 0.01). The cumulative release rate of doxorubicin from the microspheres crosslinked by oxidized-dextran in 12 hours was 83.2%, lower than that from the microspheres crosslinked by glutaraldehyde (P < 0.01). The in vitro and in vivo studies found that the duration of degradation of the microspheres crosslinked by oxidized-dextran appeared longer than those crosslinked by glutaraldehyde. Oxidized-dextran is a better crosslinking agent for preparing DR-GMs, because it has more advantages over glutaraldehyde as for hepatic artery chemoembolization.
  Sichuan da xue xue bao. Yi xue ban = Journal of Sichuan University. Medical science edition 01/2011; 42(1):119-24.
• Article: Direct in vivo injection of 131I-GMS and its distribution and excretion in rabbit.

  Yu Ma, Yi Wan, Dong-Hui Luo, Li-Geng Duan, Lin Li, Chuan-Qin Xia, Xiao-Li Chen
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  ABSTRACT: To explore the distribution and metabolism of (131)I-gelatin microspheres ((131)I-GMSs) in rabbits after direct injection into rabbits' livers. Twenty-eight healthy New Zealand rabbits were divided into seven groups, with four rabbits per group. Each rabbit's hepatic lobes were directly injected with 41.336 +/- 5.106 MBq (131)I-GMSs. Each day after (131)I-GMSs administration, 4 rabbits were randomly selected, and 250 microL of serum was collected for gamma count. Hepatic and thyroid functions were tested on days 1, 4, 8, 16, 24, 32, 48 and 64 after (131)I-GMSs administration. Single-photon emission computed tomography (SPECT) was taken for each group on days 0, 1, 4, 8, 16, 24, 32, 48, 64 after (131)I-GMSs administration. A group of rabbits were sacrificed respectively on days 1, 4, 16, 24, 32, 48, 64 after (131)I-GMSs administration. Their livers were taken out for histological examination. After (131)I-GMSs administration, the nuclide was collected in the hepatic area with microspheres. The radiation could be detected on day 48 after (131)I-GMSs administration, and radiography could be seen in thyroid areas in SPECT on days 4, 8, 16 and 24. One day after (131)I-GMSs administration, the liver function was damaged but recovered 4 d later. Eight days after (131)I-GMSs administration, the levels of free triiodothyronine and free thyroxin were reduced, which restored to normal levels on day 16. Histological examination showed that the microspheres were degraded to different degrees at 24, 32 and 48 d after (131)I-GMSs administration. The surrounding parts of injection points were in fibrous sheathing. No microspheres were detected in histological examination on day 64 after (131)I-GMSs administration. Direct in vivo injection of (131)I-GMSs is safe in rabbits. It may be a promising method for treatment of malignant tumors.
  World Journal of Gastroenterology 05/2010; 16(17):2120-8. · 2.47 Impact Factor
• Article: Experimental study of the safety of pancreas cryosurgery: the comparison of 2 different techniques of cryosurgery.

  Xiao Li Chen, Yu Ma, Yi Wan, Li Gen Duan
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  ABSTRACT: To test the feasibility of cryosurgery for pancreatic carcinoma and to observe the consequence of cryosurgery by 2 different techniques. Twelve healthy pigs underwent laparotomy, during which, chop amputation of common bile duct and duodenum were performed, meanwhile other intra-abdominal organs with the pancreas were isolated. Two different techniques of cryosurgery were performed on the pancreas. Group A (n = 6) accepted the mild hypothermic cryosurgery with liquid nitrogen superficial refrigeration, and group B (n = 6) were performed with the deep hypothermic cryosurgery at -170 degrees C with LCS2000 cryogenic surgical system. All the animals' digestive tract was reconstructed with cholecystojejunostomy and gastroenterostomy, respectively. Acute necrotizing pancreatitis occurred on all animals in group A, of which 5 of the 6 died within 1 week, whereas only 1 of the 6 reported a 4-week survival. All animals in group B survived during the observation, in which only a transient increment and a gradual correction of pancreatic amylase level were recorded. Small pancreatic pseudocyst occurred in 1 case. Mild hypothermic cryosurgery with liquid nitrogen superficial refrigeration might lead to pancreatic injury and induce acute pancreatitis, yet deep hypothermic cryosurgery with adequate time showed a promising effect in destroying pancreatic tissue and preventing acute pancreatitis.
  Pancreas 12/2009; 39(1):92-6. · 2.39 Impact Factor