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Xiang-rong Cao

Publications and source records attributed to Xiang-rong Cao.

5 recordsLinked to original sources

Soluble multimer of recombinant endostatin expressed in E. coli has anti-angiogenesis activity.

The bioactivity, refolding, and multimer formation of endostatin, particularly of recombinant endostatin produced from bacteria, are proved challenging for clinical application. In order to determine the biological activity of recombinant endostatin multimer, first, we expressed endostatin in Escherichia coli and purified it with ion-exchange chromatography. The purified active protein could elicit multimer formation spontaneously, but still has comparable activity. Aim to determine the anti-angiogenic activity of multimer endostatin, by use of RP-HPLC, we then successfully separated endostatin monomer and multimer for subjecting to anti-angiogenesis assay. The results from CAM (chorioallantoic membrane) inhibition assay showed that both monomer and multimer suppressed CAM vascularization significantly. At the dosage of 0.8 microg, inhibition rates of multimeric and monomeric proteins were about 58% and 38%, respectively. Multimeric endostatin exerted a higher activity than monomeric endostatin (p < 0.05). However, when the protein dosage is less than 0.4 microg/ml, there is no significance between their inhibition rates (p > 0.05), although both of them show a high inhibition effect in contrast to control. The results from HUVEC proliferation assay also showed similar effects at dosages of 0.6 and 1.6 microg/ml, multimer exerted a higher activity on inhibition of HUVEC proliferation comparing with monomer (p < 0.05). In conclusion, our results suggest that endostatin multimer has a comparable or higher bioactivity and multimerization will not affect its bioactivity, implying that endostatin activity is insensitive to structure conformation contributed by disulfide bonds.

Allantois↗

[Endophthalmitis after phacoemucification surgery].

OBJECTIVE: To study the infective endophthalmitis after phacoemulsification and to discuss the methods for prevention and treatment of this complication. METHODS: A retrospective analysis was performed on phacoemulsification with implantation of artificial lens underwent in 10 MaiGe Ophthalmological Centers during past 10 years (from 1993 to 2003). RESULTS: Among 63,372 cases (84,497 eyes) underwent the phacoemulsification, 14 cases suffered infective endophthalmitis with the incidence of 0.02%. In these 14 cases, 11 cases occurred before 1999 (78.6%). There were 5 cases of ruptured posterior lens capsule in these 14 cases (35.7%). Microbiological examination was performed in 11 cases (aqueous or vitreous sample), 7 cases showed positive results (63.6%), including 3 cases of staphylococcus epidermidis (42.8%), 1 case of pseudomonas aeruginosa (16.7%), 1 case of bacilli (16.7%) and 2 cases (33.4%) of fungus (yeast and candida albicans). After the treatment, the vision of 5 patients was recovered to 2.0 or more, 4 cases recovered to hand movement and light perception, enucleation was performed in 3 cases and atrophy of eyeballs occurred in 2 cases. CONCLUSIONS: The attack rate of endophthalmitis after phacoemucification surgery is 0.02%. The main pathogen is staphylococcus epidermidis. Rupture of posterior lens capsule is one of the main risk factors of endophthalmitis. Observing the operative routine strictly pre-, during and post-operatively can reduce the occurrence of infective endophthalmitis.

Aged↗

[Ross procedure in treatment of aortic disease: clinical experience of 15 cases].

OBJECTIVE: To summarize the clinical experience of Ross procedure in treatment of aorta valve diseases. METHODS: The clinical data of 15 patients with aorta valve diseases, 12 men and 3 women, aged 30 +/- 14, including 13 cases of congenital aorta valve disease, 1 case of senile degenerative aortic valve disease, and 1 case of subacte bacterial endocarditis complicated by aortic stenosis (AS), with the heart function (NYHA) of class II in 11 cases and class III in 4 cases, underwent Ross procedure from October 1994 to September 2002 in Anzhen Hospital. Before operation, ultrasound cardiography showed moderate to severe AS and/or aortic insufficiency (AI) with an average aortic valve annulus diameter (AVD) of 2.4 +/- 0.4 cm and normal pulmonary valve. Operation was performed on all patients under cardiopulmonary bypass and moderate hypothermia. The operation procedure was as follows: (1) to take off the auto-pulmonary artery valve; (2) to remove the dysfunctional aortic valve and auto-transplant the pulmonary valve on the aortic root; and (3) to put a pulmonary homograft so as to re-establish on the right ventricular outflow tract. RESULTS: The perieoperative mortality is 0. After the operation, the mean pressure gradient of aortic valve was in the normal limitation (7.23 +/- 0.14 mm Hg), the left ventricular diastolic diameter decreased significantly (P < 0.001), the left ventricular ejection fraction was 0.48 +/- 0.22, and the heart function (NYHA) was at the classes I - II in all the patients. All cases received follow-up of 1 - 9 years, their heart function was all in Class I, and the function of their aortic and pulmonary valves remained well. CONCLUSION: Ross procedure is a kind of effective alterative operation in treating patients with aortic valve disease.

Adult↗

Expression of TN4 gene and its role in human hepatocarcinogenesis from Qidong, a liver cancer risk area.

BACKGROUND: We investigated the expression and role of TN4 in the oncogenesis of human hepatocellular carcinoma (HCC) from Qidong which is a HCC risk area. METHODS: The expression of TN4 in HCC was observed using immunohistochemical staining (IHC). TN4 levels were manipulated in human liver cancer cell SMMC7721, using pcDNA3.1 eukaryotic expression constructs designed to express the complete TN4 cDNA. The biological changes of the cells were observed before and after transfection of TN4 and the change of gene expression was analysed by atlas cDNA expression array. RESULTS: Among 100 pairs of samples of HCC, TN4 down-regulation expression and up-regulation expression positive rate were 81% (81/100), 19% (19/100), respectively (P < 0.01). TN4 protein was mainly localized in cytoplasm and membrane. The positive rate of TN4 were 10% (3/30), 100% (70/70) in lymph node metastasis and no lymph node metastasis, respectively (P < 0.01). The growth rates of the derivative SMMC7721-TN4 cell lines were decreased in comparison with that of normal SMMC7721 cells and pcDNA-SMMC7721. Some gene expression was changed before and after transfection of TN4. At 30 days of post-implantation of SMMC7721-TN4, SMMC7721-pcDNA3, SMMC7721 group produced tumors of (301.9 +/- 143.4) mm(3), (2418.7 +/- 362.8) mm(3), (2317.4 +/- 587.8) mm(3), respectively, (P < 0.01). Tumor inhibiting rate was 82.4% in TN4 transfection group. Sections of tumors were observed for their degree of tissue necrosis and there was higher degree of necrosis in tumors of the TN4-SMMC7721 cell group than those of the SMMC7721, SMMC7721-pcDNA groups. CONCLUSIONS: TN4 may play an important role in the oncogenesis of human HCC, especially in Qidong, the HCC risk area and TN4 could be a candidate tumor suppressor gene for HCC.

Adult↗