BACKGROUND: Chitosan and sodium alginate are the good natural materials for microcapsule, and also used widely in tissue engineering. Our research teams have made thorough work at anticoagulant materials, but these materials are inert or simulate the liquid crYstal form of blood vessel wall. While in this experiment, on the base of our previous study, we microencapsulated heparin with biotic anticoagulation activity and other specific performances in order to enable microcapsule to have a long time releasing effect of medicine.OBJECTIVE: To microencapsulate the low molecular heparin so as to ensure the stability of heparin in vivo and analyze the effect of content of chitosan on the performance of heparin microcapsules basing on the natural chitosan and sodium alginate as the enwrapped materials of microcapsules.DESIGN: Open experiment.SETTING: Department of Material Science and Engineering, Jinan University.MATERIALS: The experiment was performed at the laboratory of Department of Material Science and Engineering, Jinan University from October 2004 to June 2005. Heparin, with relative molecular mass＜ 5 000, was provided by Shandong Freda Biochem Co., Ltd.,; Chitosan was provided by Shanghai Bio Life Science & Technology Co., Ltd, DD≥90%, η＜ 100 cps;Sodium alginate was provided by Qingdao Bright Moon Seaweed Industrial Co., Ltd. Emulsions were Span80, and CaCl2, which were both made in China.METHODS: ①Preparation of heparin/chitosan microcapsules (HCM):Some heparin aqueous solution was emulsified in liquid paraffin. The reaction system was stirred fully and presented emulsion. Then the whole reaction system was warmed to be at 50 ℃ and maintained for 20 minutes. Afterwards, 20 g/L chitosan solution was added slowly, subsequently with raising the temperature to be at 60 ℃ and then glutaraldehyde was dropwised keeping the reaction system at 80 ℃ for 1hour. Centrifugation, filtration and washing followed by washing with kerosene fully, remain organic was extracted by dehydrated alcohol with extractor were performed.Drying and xeransis in vacuum were done at last. ② Preparation of heparin-sodium alginate-chitosan microcapsules (HSCM) :Heparin aqueous solution and sodium alginate were emulsified in paraffin, and the reaction system was stirred into emulsion at room temperature for 20 minutes, then 3% CaCl2 solution containing different concentrations of chitosan was added slowly. 30 minutes later, Microcapsules were separated, washed and dried as the treatments as before. ③ Drug content and envelope efficiency were measured, heparin standard curve was determined and in vitro releasing effect of heparin microcapsules was also measured.MAIN OUTCOME MEASURES: ①Effect of chitosan solution concentration on preparation of heparin-chitosan microcapsules; ② Effect of glutaraldehyde dosage on preparation of heparin-chitosan microcapsules; ③Effect of sodium alginate concentration on hepatin-sodium alginate; ④Effect of chitosan concentration on hepatin-sodium alginate-chitosan microcapsules. ⑤ In vitro release of heparin microcapsules enwrapped by different materials. ⑥Measurement of heparin content and envelope efficiency. ⑦ Observation of heparin microcapsule under scanning electron microscope RESULTS: ①With the increasing concentration of chitosan, the color of production changed from yellow to dark, and microcapsules were increscent, but the microcapsules uniformity and property of balling were increased. ②The increasing content of glutaraldehyde led darker production.Increase of glutaraldehyde content made production bond each other severely. The glutaraldehyde, which did not react with chitosan, can solidify itself and presented anomalous microcapsules forming. ③There was not obvious balling property of the production with the change of concentration of sodium alginate. ④The balling property of microsphere was good with increasing concentration of chitosan. However, microcapsules conglutinated with each other. 2% chitosan would be better. ⑤With the increase of chitosan content, the releasing speed ofheparin became slow. ⑥The envelope efficiency was about 58% when microcapsule contained 20%(wt) of chitosan, and used chitosan only the envelope efficiency could approach to 79.9%. ⑦ The surface of microcapsules with chitosan was very compact,and with increasing of content of glutaraldehyde, microcapsules would bond each other.CONCLUSION: Chitosan at certain concentration will affect the uniformity and balling property of microcapsules. Chitosan dosage can alter the envelope efficiency of heparin. Envelope efficiency of heparin is increased and releasing speed of heparin is decreased with the increase of content of chitosan.

BACKGROUND:Polylactic acid(PLA)surface is hydrophobic and there are no nataral recognition sites,so its application is limited.Many different strategies have been studied such as composition and chemical Drafting,to produce hydrophilic groups.However,these traditional methods are always involved in complex process and many organic reagents,resulting in decrease of biocompatibility.OBJECTIVE:To conduct the surfacr modification of PL.A and improve its hydrophilicity with low temperature plasma treatment.DESIGN:Controlled observation.SETTING:Department of Materials Science and Engineering in Jinan University.MATERIAIS:The experiment was processed from October 2004 to October 2005 at Guangzhou Research Center of Artificial Organs and Materials Engineering(Ministry of Education).The mainly used materials were:Poly-D,L-lactic acid(Mr 2.9×104,Shandong Medical Instrument Institute),N-vinyl-pyrrolidone(NVP,Acros Company,purified before use).METHODS:The materials were treated in the plasma reactor under different conditions(power=150 W,t=3,2,1 minutes;power=30 W,t=10,8,5,3,1 minutes)to choose the optimal condition,and then PLA were grafted with NVP by gas phase polymerization and liquid polymerization,respectively.MAIN OUTCOME MEASURES:THe surface morphology of the films was observed with scanning electron microscopy and atomic force microscopy.The hydrophilicity of native and treated material surfaces was measured using a water contact angle meter.Surface composition was detected with Fourier transform infrared spectrometer.Mass changesmeasurement was applied to characterize the grafting efficiency.RESULTS:Scanning electron microscopy and atomic force microscopy showed that the plasma medified materials possessed coarse surface with pores and notches.Water contact angles decreased obviously from 78°to 50°after grafting,Fourier transform infrared spectrometer showed a new absorption peak at 1 637.19 cm-1,which corresponded to the carbonyl stretch vibration absorption of amide group in poly-N-vinyl-pyrrolidone.After the plasma treatmerlt at low temperature.the mass change ratio of PLA film material was-0.6.CONCLUSION:The plasma treatment and polymerization can improve the hydrophilicity and cause coarsr surface of PLA material,which will be helpful for the cell attachment.

Objective To quantitatively evaluate the metabolic changes of prostate adenocarcinoma using magnetic resonance spectroscopy (MRS).Methods Eighteen patients of prostate cancer proved by ultrasound guided systemic biopsy were enrolled in this study.All the puncture locations were marked and the corresponding (Choline+Creatine)/Citrate ratios were calculated on the basis of the MRS metabolic map.Results 204 samples were obtained and 106 of them were diagnosed as cancer.The average (Cho+Cre)/Cit ratio in the 106 positions was 2.53?1.02.The (Cho+Cre)/Cit ratio of cancer area was statistically higher than that of noncancerous area (F=8.64, P

In this paper, the resorbable and degradable biomaterials often used in recent years are reviewed. These materials include natural and synthetical ones such as collagen, protein fiber, chitosan, polylactic acid (PLA), polyglycolic acid(PGA), polyanlydrides, etc.
Biocompatible Materials ; Biodegradation, Environmental ; Biomedical Engineering

Objective To assess the safety and efficacy of radiofrequency ablation (RFA) for the treatment of large (≥5 cm in diameter) hepatic hemangiomas.Methods Clinical data of 50 patients with large hepatic hemangiomas (≥5 cm in diameter) treated with RFA between October 2007 and December 2012 were analyzed.Patients were divided into two groups (5-10 cm and ≥ 10 cm) according to tumor size.Results Thirty-two patients had 36 hemangiomas of 5-10 cm in diameter and 18 patients had 19 hemangiomas of ≥ 10 cm in diameter.Technical success,complications related to RFA,completed ablation,symptom relief,change in size of ablation zone and recurrence of the residual tumor were analyzed.The average diameters of the two groups were 7.1 ± 1.2 cm and 13.2-± 2.4 cm separately (t =-12.57,P ＜ 0.01) ; the technical achievement ratios of the two groups were both 100％ ; Seven of 32 patients with hemangiomas 5-10 cm and all the 18 patients with hemangiomas ≥ 10 cm had 13 and 61 complications related to RFA,the incidence of complications were 21.88％ and 100％ respectively (x2 =28.13,P ＜ 0.01); 94.55％ hemangiomas (52/55) acquired complete ablation,the complete ablation rates of 5-10 cm hemangiomas and ≥10 cm hemangiomas were 100％ (36/36) and 84.21％ (16/19) respectively (P =0.014).The mean diameters of ablation zone were respectively decreased to 5.3 ± 1.0 cm and 10.62±1.8 cm (t =-14.30,P ＜0.01).Conclusions RFA for hepatic hemangiomas 5-10 cm in diameter is safe and effective; while its complication for ablation of hemangiomas ≥ 10 cm is high.

Human immunodeficiency virus (HIV)-1 infection changes transcriptional profiles and regulates. the factors and machinery of the host that facilitate viral replication. Our previous study suggested that the serine/threonine kinase citron kinase (citK) promotes HIV-1 egress. To ascertain if HIV-1 infection affects citK expression in primary cells, peripheral blood mononuclear cells were infected with vesicular stomatitis virus G protein (VSV-G)-pseudotyped HIV-1 vector NL4-3-luc viruses, which resulted in remarkably increased expression of citK. citK overexpression led to a more than two-fold increase in HIV-1 production, whereas a significant decrease was observed when citK was depleted in CD4+ T cells. Infection with HIV-1 pseudoviruses induced increases in the mRNA and protein levels of citK by 2. 5- and 2. 7-fold in HEK293T cells, respectively. By cloning the 5-kb promoter of citK into a luciferase reporter system and transfecting the construct into HEK293T cells, enhanced luciferase activity was observed during HIV-1 infection. Taken together, these data demonstrate that HIV-1 infection upregulates citK expression at the transcriptional level, and thereby renders the host more susceptible to invasion by HIV-1.
CD4-Positive T-Lymphocytes ; virology ; Cloning, Molecular ; Gene Expression Regulation, Enzymologic ; HEK293 Cells ; HIV-1 ; physiology ; Humans ; Intracellular Signaling Peptides and Proteins ; genetics ; Protein-Serine-Threonine Kinases ; genetics ; Up-Regulation ; Virus Replication

Hypersusceptibility test, pyrogen test, cell cultivation, and toxicity examination were applied in the biological evaluation of the poly(lactic acid) (PLA)/chitosan composite materials. The results indicated that all the materials were negative, conforming to the ISO10993-1. The cell could grow well on the surface of the materials. So the PLA/chitosan composite materials have good biocompatibility and can be planted in the body as scaffolds.
Animals ; Biocompatible Materials ; chemical synthesis ; toxicity ; Cell Adhesion ; drug effects ; physiology ; Cells, Cultured ; Chitin ; analogs & derivatives ; chemical synthesis ; toxicity ; Chitosan ; Female ; Guinea Pigs ; Lactic Acid ; chemical synthesis ; toxicity ; Male ; Materials Testing ; Polyesters ; Polymers ; chemical synthesis ; toxicity ; Rabbits

OBJECTIVELocalization of tracheal stem cells in rat trachea.

METHODSExtracorporeal tracheal injury (Wistar rats) was induced by 5-FU. The process of regeneration was observed and analyzed by light microscopy, electron microscopy, and immunohistochemistry.

RESULTSTwelve hours after treatment with 5-FU, the tracheal epithelium shed and cells with naked nuclei were seen located sparsely on the basement membrane. Six hours after removal of 5-FU, the tracheal rings were covered with flattened epithelium. These cells were poorly differentiated under electron microscopy. Immunohistochemistry showed few proliferating cell nuclear antigen (PCNA)-negative cells sparsely scattered among PCNA-positive cells on the basement membrane. Nine hours later, electron microscopy found that these cells differentiated into mucous cells and ciliated cells. Forty-eight hours later, the tracheal rings were entirely covered by pseudostratified ciliated columnar epithelium.

CONCLUSIONSA small number of G(0) cells with naked nuclei are located sparsely on the basement membrane of the trachea. Tracheal epithelium regenerates by proliferation and differentiation of these cells. It is likely that some of these G(0) cells on the tracheal basement membrane represent tracheal stem cells.

Animals ; Cell Differentiation ; Cell Proliferation ; Epithelium ; injuries ; ultrastructure ; Female ; Fluorouracil ; Male ; Microscopy, Electron ; Proliferating Cell Nuclear Antigen ; metabolism ; Rats ; Rats, Wistar ; Regeneration ; Stem Cells ; Trachea ; injuries ; pathology ; physiology ; Wound Healing ; physiology

We herein reported a 27-year-old woman with a right renal mass for two years. She underwent laparoscopic partial nephrectomy. Immunohistochemical examination of the specimen confirmed the diagnosis of solitary fibrous tumor by revealing its positive staining for cluster of differentiation (CD)34, epithelial membrane antigen (EMA), B-cell lymphoma-2 (Bcl-2) and CD99 in the tumor cells. No adjuvant treatment was carried out. The patient was in good health without local recurrence or metastasis during 2 years of follow-up. Laparoscopic partial nephrectomy for renal solitary fibrous tumor is an alternative treatment to radical nephrectomy. It can provide a good outcome. However, further follow-up and more cases of renal solitary fibrous tumor treated with laparoscopic partial nephrectomy are necessary to compare the oncological outcome with radical nephrectomy.

OBJECTIVETo explore a new procedure for aesthetic correction of the medial epicanthal fold aim at the etiopathogenesis.

METHODSThe new Z-epicanthoplasty devise the upper and inferior margin of angle of eye medial as one angle of the Z.

RESULTSFrom 2004 to 2006, 129 patients were treated by using the method. Follow-up 6 to 24 months, all patients were satisfied by eliminating the medial epicanthal fold without obvious scar.

CONCLUSIONSThe method is more effect than traditionally Z-plasty. Our technique is a simple, advanced procedure that can be performed widely.

Adolescent ; Adult ; Blepharoplasty ; methods ; Eyelids ; surgery ; Female ; Follow-Up Studies ; Humans ; Male ; Young Adult