[Fabrication of tissue engineered vein containing valve scaffolds].

OBJECTIVE: To fabricate porous biodegradable tissue engineered vein containing valve scaffolds. METHODS: Based on the self-made cast, the tissue engineered vein containing valve scaffolds was fabricated by injection molding plus thermally induced phase separation. Poly (lactic-co-glycolic acid) (PLGA, LA/GA mole ratio 75:25) was used as matrices. Morphological structures and biocompatibility of scaffolds were tested. Cell seeding on scaffold was performed and the mechanic characteristics of cellular constructs evaluated. RESULTS: The scaffold had an inner diameter of 9 mm with a wall thickness of 0.9 mm and the thickness of valves was (0.32 ± 0.04) mm. Scanning electron microscopic (SEM) micrographs showed regular ladder-like porous structures and the average pore size and porosity of scaffolds were 10 - 20 µm and 90%. The PLGA scaffolds were biocompatible. The cellular constructs were tested in vitro, and the valve leaflets were functionally capable of opening and closing when stimulated. CONCLUSION: Based on the self-made cast, the tissue engineered vein containing valve scaffolds can be fabricated by injection molding plus thermally induced phase separation. Further researches are warranted.

[Risk factors and therapeutic strategies of deep venous thrombosis during pregnancy].

OBJECTIVE: To summarize the epidemiology and risk factors of deep venous thrombosis (DVT) during pregnancy and develop therapeutic strategies. METHODS: Twenty-nine pregnant women with DVT were admitted into our hospital between 1991 and 2010. And their clinical data were retrospectively reviewed. RESULTS: Among all cases, the occurrence (69%, 20/29) of DVT in the first trimester was highest as compared with those in the second and third trimesters. A previous history of DVT was a leading risk factor (24%, 7/29). Twenty-four cases (82.8%, 24/29) involved left lower extremities. Anticoagulation was the primary therapy. All cases were initially intravenously administrated with unfractioned heparin (UFH) or injected subcutaneously with low-molecule-weight heparin (LMWH). LMWH continued throughout pregnancy in 7 cases. The fetus had a normal development. Due to financial problems, 11 cases in the first trimester and 2 cases in the second trimester switched to oral warfarin from LMWH after the initial treatment. And warfarin was substituted by LMWH by Week 34. However the fetuses died in 4 cases while the other fetuses were normal. Nine cases in the first trimester decided to terminate pregnancy. CONCLUSION: Treatment decisions during pregnancy carry potential implications for both maternal and fetal health and life. Therefore the DVT strategies during pregnancy differ from those during non-pregnancy. Special cautions should be exercised for the treatment of DVT during pregnancy.

[Risk factors and therapeutic management of deep venous thrombosis in hospitalized children].

OBJECTIVE: The incidence and treatment regimen for deep venous thrombosis (DVT) in hospitalized children in China are rarely reported. This report was to assess the incidence, risk factors and treatment strategy for deep venous thrombosis (DVT) among hospitalized children admitted to the First Affiliated Hospital, Sun Yat-sen University, a single tertiary-care hospital. METHODS: In twenty years between 1989 and 2009, 12 DVTs in hospitalized children (< 17 years old) were identified in this hospital. Clinical data were retrospectively reviewed. RESULTS: The incidence of DVT in hospitalized children was low, however, it demonstrated increasing trend from 0.52 per 10 000 admissions between 1989 and 1999 to 3.18 per 10 000 admissions between 2000 and 2009 in this hospital. Infection and trauma were the mostly frequent causes of DVT in hospitalized children. The catheter-related DVT was increasingly prevalent cause for DVT in hospitalized children. The other causes included nephritic syndrome, tumor, systemic lupus, and congenital plasma C protein deficiency. Two patients were complicated with pulmonary embolism. Only one neonate died due to kernicterus. Anticoagulation therapy was the first recommended treatment choice in hospitalized children with DVT, especially more low-molecular-weight heparin in recent 10 years. Antithrombotic treatment was used in 9 children older than 30 days through peripheral venous access, its application should be meticulously cautious in dosage. No bleeding occurred in all the patients. CONCLUSIONS: Cautions should be given to DVT among hospitalized children due to its increasing incidence and special treatment pattern compared with adult patients.

Effects of antiatherosclerosis in carotid artery by RNAi-mediated silencing of MCP-1 expression.

BACKGROUND: Our objective was to identify the effects of MCP-1 siRNA in vivo transfection in an atherosclerosis model on local expression of MCP-1 and pathogenesis of atherosclerosis. METHODS: Carotid atherosclerosis was induced in 28 New Zealand white rabbits. Rabbits were divided into three groups randomly: RNAi group, model group, and blank plasmid group. siRNA-expressing vector was transfected to blood vessels by liposomes. The carotid arteries were processed for morphological evaluation. Local expression of MCP-1 was detected by immunohistochemistry, RT-PCR, and Western blot. RESULTS: On hematoxylin and eosin-stained sections, partial endothelial cells detached while intimae were less thickened in the RNAi group compared to the model and blank plasmid groups; the I:M ratio was significantly reduced to 1.46 in the RNAi group compared to the model and blank plasmid groups (5.55 and 5.27, respectively). The results of immunohistochemistry showed that MCP-1 expression was less colorized and less positive in the RNAi group. RT-PCR and Western blot showed reduced expression in the RNAi group than in the model and blank plasmid groups. There were highly positive correlations between semiquantitative RT-PCR and the I:M ratio (r = 0.968). CONCLUSION: Expression of MCP-1 was successfully inhibited by transfecting MCP-1 siRNA expression plasmid to the carotid artery, and the progression of atherosclerosis was restricted by RNAi-mediated silencing of MCP-1 expression.

[Experience of surgical treatment of carotid body tumor after preoperative embolization of feeding vessels].

OBJECTIVE: To evaluate the effect of preoperative embolization of the feeding vessels of carotid body tumor in the treatment thereof. METHODS: 33 patients with carotid body tumors not less than 3 cm in diameter were examined by color Doppler ultrasound. Polyvinyl alcohol particle 250-1000 microm in diameter were suspended in meglumine diatrizoate or Ultravist and then injected via microcatheter into the feeding vessels until detainment or reflux was seen. Operation was performed 1 day later on 23 patients and 4 days later on 10 patients. External carotid artery to internal carotid artery bypass was performed on 1 case, anastomosis of common carotid to internal carotid artery with auto-saphenous vein interposition on 3 cases, and repair of internal carotid artery on 1 case. RESULTS: One-stage resection was completed on all tumors. One case suffered contralateral hemiplegia two times in the operative day, on the next day the contralateral lower limb could move, but the patient could not speak clearly and his tongue was not in right position, after 3 months he was completely recovered and MRI illustrated cranial infarction. CONCLUSION: An important adjunct in treating large carotid body tumor, preoperative embolization makes the surgical exploration proceed much smoother, blood loss become less, and morbidity lower.

Influence of In-Gap States on the Formation of Two-Dimensional Election Gas at ABO3/SrTiO3 Interfaces.

We explored in-gap states (IGSs) in perovskite oxide heterojunction films. We report that IGSs in these films play a crucial role in determining the formation and properties of interfacial two-dimensional electron gas (2DEG). We report that electron trapping by IGSs opposes charge transfer from the film to the interface. The IGS in films yielded insulating interfaces with polar discontinuity and explained low interface carrier density of conducting interfaces. An ion trapping model was proposed to explain the physics of the IGSs and some experimental findings, such as the unexpected formation of 2DEG at the initially insulating LaCrO3/SrTiO3 interface and the influence of substitution layers on 2DEG.

[Effect of interleukin-8 in cell invasion and proliferation of human breast cancer].

OBJECTIVE: To identify the effect of interleukin-8 in cell progression and invasion of human breast cancer. METHODS: Human cytokine antibody arrays were applied to screen a panel of cytokine expression from 11 human breast cancer cell lines, and the mechanism of identified key factors involved in breast cancer progression was studied. RESULTS: Profiling of cytokine expression showed the expression of interleukin-8 was related to estrogen receptor status, metastasis and vimentin status in the 11 human breast cancer cell lines. Elevated expression of interleukin-8 in breast cancer cells had positive correlation with breast cancer invasion. Neutralization of antibody against interleukin-8 specifically blocked interleukin-8-mediated cell invasion. However, anti-interleukin-8 antibody did not influence the proliferation of breast cancer cells. CONCLUSION: Interleukin-8 may be the key factor involved in human breast cancer progression and invasion, and play an important role in cell invasion of breast cancer.

The -A2518G polymorphism in the MCP-1 gene and inflammatory bowel disease risk: A meta-analysis.

OBJECTIVE: The monocyte chemoattractant protein-1 (MCP-1) -A2518G gene polymorphism has been found to be involved in the susceptibility to inflammatory bowel disease (IBD); however, the results of existing studies are controversial. The aim of this meta-analysis was to assess the relationship between the MCP-1 -A2518G polymorphism and the risk of IBD. METHODS: PubMed, EMBASE and MEDLINE were searched for studies assessing the relationship between the -A2518G polymorphism in MCP-1 gene and the risk of IBD. Available data were extracted and statistically analyzed using STATA 12.0. RESULTS: A total of five publications involving 3137 individuals (1818 IBD cases and 1319 controls) were included in the meta-analysis. A combined analysis revealed that the MCP-1 -A2518G polymorphism in was a protective factor for GG + AG vs AA (OR 0.76, 95% CI 0.67-0.87, P = 0.000). Subgroup analysis by ethnicity showed that among European patients the AG + GG homozygote, unlike the AA homozygote, had a protective effect against IBD (OR 0.73, 95% CI 0.63-0.84, P = 0.000), but did not do so among Asian and African patients. Subgroup analysis by disease subtype suggested the -A2518G polymorphism in MCP-1 had a protective effect against Crohn's disease (OR 0.69, 95% CI 0.58-0.81, P = 0.000), but not against ulcerative colitis. CONCLUSIONS: Our meta-analysis suggested that the -A2518G polymorphism in MCP-1 may be a protective factor for IBD in European populations. Further studies are required to confirm these findings.

Clinical analysis of vascular anomalies: a hospital-based retrospective study of 592 patients in southeast China.

BACKGROUND: Vascular anomalies are common and multidisciplinary involved diseases. The greatest impediment to their treatment in the past was their confusing terminology and clinical heterogeneities. This hospital-based retrospective study assessed some clinical characteristics, diagnosis, therapies and outcomes of patients with vascular anomalies in southeast China. METHODS: A total of 592 vascular anomalies patients (patients with intracranial tissues or viscera involved were excluded), admitted to the First Affiliated Hospital of Sun Yat-sen University from January 2006 to September 2009, were enrolled in the study. Data for clinical characteristics, diagnosis, therapies and outcomes were collected and analyzed. RESULTS: Of the 592 patients, the male:female ratios in the vascular tumor group (n = 187) and the vascular malformation group (n = 405) were 1:1.49 and 1:1.06 respectively, with no significant difference between them. The mean onset age of the vascular tumor group was significantly younger than that of the vascular malformation group (p < 0.001). The head and neck were the most commonly (31.4%) involved areas in vascular anomalies. A total of 23.8% of the patients with vascular anomalies had definite symptoms caused by the vascular lesions. In the vascular tumor group, 94.1% of them were infantile hemangiomas. Venous malformation was the most common (41.0%) subtype of vascular malformations. Surgical therapy was undertaken in 94.2% of the patients with vascular anomalies. Of the 519 patients available for the 16 - 58 month follow-up, 322 patients (62.0%) were cured, 108 patients (20.8%) were markedly improved, 57 patients (11.0%) were partially improved, and 32 patients (6.2%) were uncured. CONCLUSIONS: Vascular anomalies are clinically heterogeneous. While the outcome is generally favorable, further effort should be made to determine the appropriate terminology and management.

Intensive statin therapy: a favorable adjunct to the improvement of small-diameter vascular grafts.

To assess the effect of intensive statins therapy on the outcome of small-diameter vascular prosthesis, we investigated whether atorvastatin treatment (30 mg/d) could accelerate the re-endothelialization process and improve the patency rate in a canine infrarenal abdominal aorta-expanded polytetrafluoroethylene (ePTFE) bypass model. Furthermore, we also evaluated the effect of atorvastatin on the migratory and adherent capacity of circulating endothelial progenitor cells (EPCs) in vitro. Improved patency was confirmed by Doppler sonography and arteriography. Histological and scanning electron microscopy illustrated enhanced re-endothelialization process. Treatment with atorvastatin enhanced the circulating pool of EPCs with fortified migratory and adherent capacity. Reverse transcriptase-polymerase chain reaction (RT-PCR) analysis showed that atorvastatin treatment increased endothelial nitric oxide synthase (eNOS) and kinase insert domain receptor (KDR) messenger RNA (mRNA) expression in cultured EPCs and neointima. In conclusion, intensive statin therapy could be considered a favorable option to improve small-diameter vascular graft patency.

[Effect of L-arginine on diabetic rats].

OBJECTIVE: To observe the effect of L-arginine on diabetic rats. METHODS: Forty adult male Lewis rats were randomized equally into diabetic and normal control groups, and the former rats were treated intraperitoneally with streptozotocin to induce diabetes mellitus. Seven days later, half of the diabetic and normal rats were injected intraperitoneally with L-arginine at the daily dose of 1 g/kg, while the remainder were given saline instead. All the rats were euthanized on 10 days after L-arginine or saline treatment, and their body weight, plasma protein, arginine and sugar, food and water intake were analyzed. RESULTS: Diabetic rats had obviously decreased body weight, plasma protein and arginine but increased blood sugar and food and water intakes in comparison with the control rats. L-arginine significantly increased plasma protein and arginine, decreased food and water intakes, but failed to prevent weight loss and blood sugar increment in diabetic rats as compared to their saline-treated counterparts. L-arginine supplementation did not result in any changes other than arginine elevation in the control rats. CONCLUSION: L-arginine supplementation can partially improve polydipsia and polyphagia and increase plasma protein in diabetic rats.