Study on the relationship between restenosis and endothelial function after interventional surgery for diabetic lower extremity arteriopathy / 中国现代医生

@#Objective To explore the relationship between postoperative restenosis and vascular endothelial function in patients with lower extremity arterial disease(LEAD).Methods A retrospective analysis was performed on 133 patients with diabetic lower extremity arteriopathy who had successfully undergone interventional therapy in our hospital,and the patients were followed up for one year,and the patients were grouped according to whether restenosis occurred,with 25 cases in the restenosis group and 108 cases in the non-stenosis group.The patient's vascular endothelial function index,inflammatory factor level,blood lipid four items and hemoglobin A1c(HbAlc)were detected,and peripheral blood cells of patients in the stenosis group and non-stenosis group were isolated for transcriptome sequencing.Multivariate unconditional logistic regression analysis was used to screen for independent risk factors for vascular endothelial function in postoperative restenosis.Results Serum endothelin-1(ET-1),von Willebrand factor(vWF),thromboxane B2(TXB2),vascular cell adhesion protein 1(VCAM-1),and nitric oxide(NO)were significantly higher in the stenosis group than in the non-stenosis group,while endothelial nitric oxide synthase(eNOS)and vascular endothelial growth factor(VEGF)were significantly lower than those in the non-stenosis group(P<0.01).There was no significant difference in blood lipids between the two groups(P>0.05).The HbAlc of the stenosis group was significantly higher than that of the non-stenosis group(P<0.01).The inflammatory factors in the stenosis group were significantly higher than those in the non-stenosis group(P<0.05).Transcriptome sequencing analysis results are consistent with test results.Multivariate Logistic regression analysis showed that TNF-α,IL-6,ET-1,and vWF were independent risk factors for LEAD vascular restenosis(P<0.05).Conclusion Vascular endothelial function indexes(ET-1,vWF)and inflammatory factors(TNF-α,IL-6)are independent risk factors for restenosis after interventional surgery.

Impact of the transforming growth factor-β pathway on vascular restenosis and its mechanism / 中南大学学报(医学版)

As a crucial regulatory molecule in the context of vascular stenosis, transforming growth factor-β (TGF-β), plays a pivotal role in its initiation and progression. TGF-β, a member of the TGF-β superfamily, can bind to the TGF-β receptor and transduce extracellular to intracellular signals through canonical Smad dependent or noncanonical signaling pathways to regulate cell growth, proliferation, differentiation, and apoptosis. Restenosis remains one of the most challenging problems in cardiac, cerebral, and peripheral vascular disease worldwide. The mechanisms for occurrence and development of restenosis are diverse and complex. The TGF-β pathway exhibits diversity across various cell types. Hence, clarifying the specific roles of TGF-β within different cell types and its precise impact on vascular stenosis provides strategies for future research in the field of stenosis.

Numerical Simulation and Experimental Study on Vascular Mechanical Properties of Coronary Degradable Stent Intervention / 医用生物力学

Objective To explore the effect of vascular stress changes on endothelial function recovery and vascular restenosis inhibition in dynamic degradation process of the degradable stent. Methods The material parameters of the hyper-elastic vascular constitutive relationship was fitted, and the stress distribution on the intima of the blood vessel before stent implantation and during dynamic degradation was calculated by numerical simulation. In vitro culture experiments were carried out, and the stretch ratios of the silicon chambers were 0%, 5%, 10% and 15%, respectively, to simulate the mechanical environment at different degradation stages, and to explore the effects of different stretch ratios on growth state of the endothelial cells （ECs）. Results After the stent was completely degraded, the circumferential intimal stress and strain of the vessel were restored to 0.137 MPa and 5.5%, which were close to the physiological parameters (0.122 MPa, 4.8%) before stent implantation. In vitro experiments showed that the survival rate of ECs was the highest under the condition of 0.1 MPa circumferential stress and 5% strain, and adhesion growth could be achieved. Conclusions With the occurrence of stent degradation process, the circumferential stress and strain of the intima were restored to a range close to physiological parameters, which promoted the growth of ECs. The recovery of intimal function could effectively inhibit the process of vascular restenosis. The results can provide the theoretical basis and experimental platform for studying coronary intervention for the treatment of vascular restenosis.

Efficacy of cutting balloon versus semi-compliant balloon for predilation of coronary bifurcation lesions / 中国组织工程研究

BACKGROUND: There is no efficient and unified optimal scheme for treating coronary bifurcation diseases. Simple strategies such as drug-eluting stent implantation in the main branch and drug-coated balloon dilation in the sub-branches are mostly adopted. However, direct drug-coated balloon dilation cannot overcome the problem of elastic retraction of vascular wall, and there is still a risk of branch loss in the long term. OBJECTIVE: To investigate the efficacy and safety of a cutting balloon versus a semi-compliant balloon for predilation of coronary bifurcation lesions. METHODS: From August 2016 to May 2018, 110 patients with coronary bifurcation lesions admitted at Jiaozuo People’s Hospital were selected, including 83 males and 27 females, aged 18-88 years. The patients were randomized into observation and control groups (n=55/group) and received percutaneous coronary intervention. The main branch in the observation group was predilated by a cutting balloon prior to drug-eluting stent implantation, and the sub-branches were predilated by a cutting balloon prior to drug-coated balloon dilation. The main branch in the control group was predilated by a semi-compliant balloon prior to drug-eluting stent implantation, and the sub-branches were predilated by a semi-compliant balloon prior to drug-coated balloon dilation. Immediate postoperative angiography was performed to determine the forward blood flow TIMI grading of main branches and sub-branches and whether vascular dissection occurred. Coronary angiography quantitative analysis was used to detect the reference diameter, minimum inner diameter and stenosis degree of main and sub-branches before, immediately, 6 and 12 months after surgery. Major cardiovascular adverse events within 12 months after surgery were recorded in both groups. The study was approved by the Ethics Committee of Jiaozuo People’s Hospital. RESULTS AND CONCLUSION: (1) Immediate postoperative angiography showed that the TIMI level 3 rate of the main branches and sub-branches in the observation group was higher than that in the control group (P=0.007, 0.015), the incidence of vascular dissection was lower than that in the control group (P=0.023, 0.012), and the emergency target vessel reconstruction rate was lower than that in the control group (P=0.006, 0.026). (2) The success rate of coronary artery maintenance immediately and at 6 and 12 months after surgery in the observation group was higher than that in the control group (all P < 0.001). (3) The minimum inner diameter of main branches and sub-branches in the observation group was larger than that in the control group immediately and at 6 and 12 months after surgery (all P < 0.01). The degree of inner diameter stenosis was smaller than that in the control group (all P < 0.01). (4) The target vessel restenosis rate of main branch and sub-branches in the observation group was lower than that in the control group within 12 months after surgery (P=0.038, 0.043). The incidence of major cardiovascular adverse events was lower than that in the control group (P=0.025). (5) These results indicate that in coronary bifurcation lesions, drug-eluting stent implantation is suitable for main branch lesions and drug coated balloon is suitable for sub-branch lesion. Cutting balloon predilation is safer and more effective than semi-compliant balloon predilation. Cutting balloon predilation can also reduce the rate of target restenosis and the incidence of major cardiovascular adverse events.

Expression and role of neutrophil gelatinase-associated lipocalin (NGAL) signaling pathways in the early stage of vein graft restenosis of a pig model / 中国胸心血管外科临床杂志

@#Objective     To investigate the expression of neutrophil gelatinase-associated lipocalin (NGAL) signaling pathways in the early stage of porcine vein graft restenosis, and to explore the possible role and mechanism in the early vein graft restenosis after coronary artery bypass surgery. Methods     We selected 18 ordinary healthy pigs weighing 25-30 kg and collected samples of the vein graft of pigs at the preoperation and postoperative days 7, 14 and 30. Hematoxylin-eosin (HE) staining and Masson staining, immunohistochemical method were used to observe the neointimal hyperplasia, the migration of smooth muscle cells and and vascular remodeling of the vein bypass graft. The expression changes of NGAL, matrix metalloprotenase (MMP)9, MMP2 and tissue inhibitor of metalloproteinase (TIMP)1 in different periods of the vein bypass graft was tested. Results     By HE and Masson staining, with the passing of modeling time, degradation of collagen matrix in the vein graft, gradually thickening of muscle fibers and the migration to the inner membrance and vascular remodeling caused the vascular stenosis. By immunohistochemistry, NGAL, MMP9  and MMP2 of normal vein in the model were seldom expressed and even did not express. At 14 days after the modeling, NGAL expression in the membrane layer of blood vessels began to appear, peaked at postoperative 30 days, and began to appear in the inner membrance. MMP9, MMP2 expression began to appear at postoperative 7 days, peaked at postoperative 14 days, and tended to decline at postoperative 30 days. TIMP1 expression was less in normal vascular walls and at the 14 days after the modeling, expression peaked in the vein graft. Conclusion     NGAL, MMP9, MMP2 and TIMP1 may be involved in the formation of early vascular graft restenosis. NGAL as initiator, results in the expression of MMP9 and MMP2, and participates in the degradation of collagen matrix and the migration of smooth muscle cells in vein grafts. TIMP1 as a negative factor, may play an important role in maintaining their own balance.

Effects of stent parameters on vascular wall shear stress / 医用生物力学

Objective To investigate the effects of different stent parameters on the development of restenosis, so as to provide references and basis for the design of stent forms. Methods Stents were categorized into groups according to stent unite length, strut number, strut cross-section diameter, stent depth into fluid, strut cross-section shape. The influence of different parameter settings on wall shear stress distributions was investigated based on three-dimensional computational fluid dynamics (CFD) simulation. Results The strut cross-section diameter had the most obvious impact on wall shear stress. It would lead to the increase of low wall shear stress area with shorter stent unite length, more strut number, larger strut cross-section diameter and deeper stent depth into the fluid. In comparison with triangular and square cross-section shape, the low shear stress area was much smaller by using stent with circular cross-section. Conclusions It is suggested that the circular cross-section shape should be adopted in stent design, with preference to reducing strut cross-section diameter, strut number and stent depth into the fluid, while increasing stent unite length.

Research Advances in Molecular Biology of Vascular Restenosis / 中国普外基础与临床杂志

Objective To review the research advances in molecular biology of vascular restenosis.Methods The literatures about molecular biology of vascular restenosis were reviewed.Results Current transgenic ways had some advantages and disadvantages. Gene therapy with HSV tk, Rb,p21,p27,p53,c myc, c myb, vascular endothelial growth factor,bFGF,platelet derived growth facfor,nuclear factor ?B and so on inhibited vascular restenosis.Conclusion A better transgenic system and gene combination therapy will be effective to treat vascular restenosis.

Gene therapy for restenosis of the vessel / 中国普通外科杂志

Objective To understand the experimentnl resluts and the advance in gene therapy for restenosis of the vessel. Method Literature review was made on gene therapy for restenosis directly at cytotoxic, cell cycle regulators, intracellular signal transducers, transcription factors, cytokines growth factors, nitric oxide and Fas ligand. Results cytotoxic gene therapy by thymidine kinase and cytosine deaminase, mutant retinoblastoma protein (Rb), cyclin-dependent kinases(cdk) inhibitors (such as p21 p27 and p53), antisense basic fibroblast growth factor (bFGF) blocking intracellular signal transduce by A-Raf and C-Raf, antisense Ag ??, promoting NO, ?-nterferon, vascular endothelial growth factor (VEGF) and platelet-derived growth factor (PDGF), ? chain synthesize suppressing nuclear factor-kB (NF-kB) overexpression of gax and Fas ligand can inhibit restenosis of the vessel. Conclusions The effect of gene therapy for restenosis of the vessed is obvious in experimental studies. Conbination of more gene and several links gene therapy is the research direction in the future.