Objective To observe the level of vascular endothelium growth factor A( VEGF-A) in exhaled breath condensate ( EBC) of patients with acute lung injury/acute respiratory distress syndrome ( ALI/ARDS) , and investigate its clinical significance. Methods EBC of 23 patients with ALI/ARDS by mechanical ventilation in intensive care unit ( ICU) were collected with improved EcoScreen condenser. EBC of 17 normal control subjects were collected with EcoScreen condensor. The level of VEGF-A was measured by ELISA in EBC and serum. The levels of VEGF-A in EBC of patients with different grades of lung injuries were compared, and the correlation was analyzed between the level of VEGF-A and clinical indicators. Results The level of VEGF-A in EBC was lower in the patients with ALI/ARDS than that of control subjects [ ( 49. 88 ±6. 32) ng/L vs. ( 56. 50 ±6. 323) ng/L, P lt;0. 01] , the level of VEGF-A was higher in the ALI patients than that of ARDS patients [ ( 53. 56 ±5. 56) ng/L vs. ( 45. 86 ±4. 45) ng/L, P lt;0. 01] ,and higher in the survival patients than that of the died patients [ ( 51. 92 ±6. 28) ng/L vs. ( 46. 05 ± 4. 58) ng/L, P lt;0. 05] . The level of VEGF-A in EBC was negatively correlated with lung injury score and A-aDO2 /PaO2 ( r = - 0. 426 and - 0. 510, respectively, P lt;0. 05) , and positively correlated with PaO2 /FiO2 and PaO2 ( r =0. 626 and 0. 655, respectively, P lt; 0. 05) . The level of VEGF-A in serum was not different between the ALI/ARDS patients and the control subjects, between the ALI and ARDS patients, or between the survival and the died patients ( all P gt;0. 05) . The level of VEGF-A in serumhad no correlation with lung injury score, A-aDO2 /PaO2 , PaO2 /FiO2 , or PaO2 ( all P gt;0. 05) . Conclusion The changes of VEGF-A in EBC of patients with ALI/ARDSmay serve as an indicator for severity and prognosis evaluation.
Objective To investigate the long effect of nonpulsatile flow on changes of structure and function in pulmonary microcirculation and to identify the pulmonary reconstruction under this blood perfusion. Methods Canine models with nonpulsatile flow in the right lung was established, and sacrificed 6 months later. Compare endothelial nitric oxide synthase (eNOS) in vascular endothelium, apoptosis in smooth muscle cell with immunohistochemistry by streptavidinbioepidermmultienzyme complex methodes, and observe structural changes in pulmonary arterioles with optical microscope. Results The expression of eNOS in the right nonpulsatile flow perfusing lung was weaker as compared to the left lung （10 846.7±177.8 vs. 13 136.1±189.6;t＝2.240, P=0.040）, the fas was ber as compared to the left lung（14 254.1±217.1 vs. 11 976.7±195.7; t＝2.160, P=0.040）. The ratio of wall thichness/vessel diameter in the right lung（13.64%±12.80% vs. 14.96%±13.10%） and wall area/vessel area(46.40%±11.70% vs. 47.80%±12.20%) was lower as compared to the left lung(Plt;0.05). Conclusion Longterm nonpulsatile flow can decrease the expression of eNOS, contract the muscles in capillary net, and increase pulmonary vascular resistance. Moreover it canincrease the arteriole apoptosis, leading to vascular structure remodeling.
Objective To observe expression of human antithrombin Ⅲ (hAT-Ⅲ) gene in vascular endotheliallike cells(VELCs) after transfected. Methods Human bone marrow mesenchymal stem cells(BMMSCs) were isolated, cultured and proliferated in vitro, and were differentiated into VELCs. Then, the VELCs were divided into experimental group cells and control group cells randomly. Plasmid DNA with hAT-Ⅲ gene was transfected into VELCs by liposome mediate. At last, the hAT-Ⅲ expression was determined by reverse transcriptpolymerase chain reaction(RT-PCR), immunohistochemical stain(IHCS), Westernblotting and chromogenic substrate assay at 72h and 96h respectively. In the control group, the plasmid DNA was replaced by TE buffer, and the other methods were the same as the experimental group. Results RT-PCR showed that the specific DNA fragment of hAT-Ⅲ could be amplifed in the experimental group cells, none in the control group. IHCS showed positive expression of hAT-Ⅲ in the experimental group cells, negative in the control group. Westernblotting showed that the specific band of hAT-Ⅲ could be detected in the experimental group cells culture fluid, none in the control group. Chromogenic substrate assay showed that the hAT-Ⅲ activity of the experimental group cells was 9.50%±1.52%, the control group was 1.83%±1.17%， there was statistically difference between two groups(t=7.910，Plt;0.01). Conclusion The hAT-Ⅲ gene could be transfected into VELCs and expressed successfully.
Objective To review the studies on vascular endothelium growth factor (VEGF) gene therapy for patients with chronic critical limb ischemia. Methods Advance in molecular biology of VEGF, mechanism of new vessel formation induced by VEGF and achievement of improving blood flow in patients with critical limb ischemia due to VEGF expressed by gene transfer in recent years has been reviewed in this article. Results Preclinical studies showed that VEGF can stimulate the development of collateral arteries in animals with limb ischemia, a concept called “therapeutic angiogenesis”, clinical results demonstrated that VEGF expressed by gene transfer can promote new vessel formation in patients with critical limb ischemia and improve significantly the prognosis for them.Conclusion VEGF gene transfer provide a novel treatment strategy for patients with critical limb ischemia, who neither had favorable response to phamarcological treatment nor were suitable for surgical reconstruction or revascularization.