Objective:To investigate the mechanism of methyltetrahydrofolate reductase ( MTHFR) C677T polymorphism in the pathogenesis of lower extremity deep vein thrombosis (DVT). Methods:Used retrospective controlled study method, a total of 64 DVT patients (DVT group) and 96 healthy people (control group) were enrolled in the Affiliated Hospital of Traditional Chinese Medicine, Xinjiang Medical University from August 2019 to August 2021. Clinical manifestations and related detection, including D-dimer, fibrinogen, prothrombin time, prothrombin activity and prothrombin time-international normalized ratio of the subjects were recorded, and plasma homocysteine (Hcy) and soluble endothelial cell protein C receptor (sEPCR) were detected by enzyme linked immunosorbent assay (ELISA). The polymorphism of C677T locus of MTHFR gene was detected by polymerase chain reaction-restricted fragment length polymor-phism (PCR-RFLP), and the differences of blood indexes and MTHFR genotypes between the two groups were compared. Measurement data with normal distribution were represented as mean ± standard deviation ( ± s), and comprison between groups was conducted using the t-test; the skewness data were expressed by M( Q1, Q3), and rank-sum test was used for inter-group comparison. comprison between groups of count data was conducted using the chi-square test or Fisher exact probability. Results:Compared with the control group, DVT group showed more symptoms of limb skin redness, limb swelling, skin temperature rise, local tenderness, skin rupture, skin tension, pigmentation, limb movement and sensory disturbance, the difference were statistically significant ( P<0.05); the prothrombin time-international normalized ratio [0.98(0.95, 1.04) vs 1.05(1.00, 1.13)], fibrinogen [2.76(2.31, 3.30) mg/L vs 3.36(2.74, 4.35) mg/L], D-dimer [0.52(0.38, 0.62) mg/L vs 4.73(2.44, 12.05) mg/L], Hcy[(1 639.03±390.29)ng/mL vs (2 423.03±631.95) ng/mL] and sEPCR [(108.62±25.07) ng/mL vs (137.79±26.23) ng/mL] in DVT group were significantly higher than those in control group, the difference were statistically significant ( P<0.05); the prothrombin activity [90.70% (75.80%, 100.00%) vs 103.00%(93.00%, 112.50%)] was significantly lower than that of the control group, the difference was statistically significant ( P<0.05). Compared with the control group, CC, CT, TT genotype frequency and allele frequency of MTHFR C677T site in DVT group showed a trend of change, but the difference were not statistically significant ( P>0.05). Conclusion:TT mutation at MTHFR C677T site in patients with DVT has an increasing trend, which may promote the expression level of Hcy, and high expression of Hcy and sEPCR can induce the occurrence and development of DVT.

Objective: By modeling ischemic foot ulcers in experimental rabbits, the mechanism of healing in animal models was investigated. Methods: Sixty healthy male clean grade New Zealand rabbits were 3 months. The weight range was 2.1-2.5 kg. Randomly draw auording to the number, the experimental rabbits were randomly divided into 4 groups, namely, no ischemia-no ulcer-no intervention group (group A), no ischemia-no ulcer-no intervention group (group B), no ischemia-no ulcer-no intervention group (group C) and no ischemia-ulcer-intervention group (group D), with 15 rabbits in each group. Ischemic foot ulcers experimental rabbit building complete after 24 h, will naturally exposed ischemic foot ulcers in the low frequency electromagnetic field on experimental rabbit 7 d feeding experiment, the experimental rabbits ischemia crus muscle and the ulcer base were collected, and plasma by enzyme-linked immunosorbent assay (ELISA) verification tests in experimental rabbit plasma hypoxia-inducible factor 1 alpha subunit (HIF-1α), matrix metalloproteinases 9 (MMP-9) and soluble leukocyte differentiation antigen 40 ligand 1 (sCD40L1) expression level, while detecting ulcer healing area change, hematoxylin-eosin staining was used to detect and analyzed the pathological changes of ulcerated skin. Measurement data were expressed as mean±standard deviation (Mean±SD), one-way analysis of variance was used for comparison between groups, and LSD method was used for pairwise comparison. Results: The concentration of MMP-9 and sCD40L1 in group D were (40.510±10.155) ng/ml and (44.580±19.138) ng/ml, respectively. Concentrations in group C were (93.210±17.838) ng/ml and (318.500±52.680) ng/ml, respectively. Group D was significantly lower than group C, and the difference was statistically significant (P< 0.000 1). The concentrations of HIF-1α in group D was (249.700±71.824) ng/ml, and that in group C was (124.830±20.110) ng/ml. The concentration in group D was significantly higher than that in group C, and the difference was statistically significant (P< 0.000 1). The concentrations of HIF-1α, MMP-9 and sCD40L1 in group B were (181.590±31.927), (78.950±16.652) and (173.670±43.048) ng/ml, respectively. The concentrations of group A were (35.420±9.916), (32.700±6.449) and (47.440±11.831) ng/ml, respectively. The concentration in group B was significantly higher than that in group A, the difference was statistically significant(P<0.000 1). The concentration of HIF-1α in group D was (249.700±71.824) ng/ml, and the concentration of group A was (35.420±9.916) ng/ml. The concentration of group D was significantly higher than that of group A, and the difference was statistically significant (P=0.000 1). The concentration of the MMP-9 in the group D was compared with the concentration of group A, and the difference was not statistically significant (P=0.207). The concentration of sCD40L1 in group D was (44.580±19.138) ng/ml, and that in group A was (47.440±11.831) ng/ml. The difference between group D and group A was not statistically significant(P=0.858). The healing area of ulcer was (1.855±0.394) cm² in group D and (0.653±0.269) cm² in group C. Group D was significantly higher than group C, and the difference was statistically significant (P<0.000 1). Hematoxylin-eosin staining results of ulcer skin showed that the epithelial of ischemic foot ulcer was significantly atrophied, hyperkeratinized, and the acinous cell layer was atrophied with a small amount of obvious inflammatory cell infiltration and hyperplasia of small vessels. After intervention, the symptoms were relieved. Conclusion Low frequency electromagnetic fields can promote the expression of HIF-1α in experimental rabbits, inhibit the expression of MMP-9 and sCD40L1, and promote the healing of ischemic foot ulcer.