Experimental And Clinical Research Of Chitosan And Its Compounds On The Healing Of Lower Limb Ischemic Ulcers

Chronic leg ulcer,more than a month still not healed,the ulcer is a common surgical disease,the incidence of 0.12-1.1%,including over 60 incidence of 0.5 to 3%,more than 80-year-old is as high as 5%.Current source can be divided into Vascular ulcer,Diabetic foot ulcer,Pressure ulcer,Traumatic ulcer,Neurotrophic ulcer,Malignant ulcer,etc.The vascular ulcer can be divided into chronic venous ulcer and chronic ulcer artery.When critical lower limb ischemia,severe lower limb artery stenosis or occlusion,leading to local blood supply to produce a series of pathophysiological effects,eventually produce rest pain,ischemic ulcers or gangrene.Appropriate dressing can provide an optimum for the wound "environment",besides has good absorption drainage capacity,should also has antibacterial,the pain and the ability to promote wound healing.Chitosan with anti-infection,hemostatic,induction of tissue repair and cell proliferation and so on characteristics,can be used as a kind of ideal wound dressings.Chitosan and its complexes experimental research for the treatment of lower limb ischemic ulcer in ratsObjective:Establishment of animal model,the simulation of human lower limb ischemia.Chitosan with physiological saline gauze was applied to animal models,compared two groups of healing area and healing rate,and analyze the clinical effect of two kinds of materials.To explore the effect of chitosan on ischemic ulcer healing and related factors of expression.Methods:Animal experiments:Yangzhou university comparative medical center provided 60 healthy,same-age,male SD rats without special pathogen,weighing 220-260g/animal.After anesthesia,inguinal oblique incision,microscope free right external iliac artery,femoral artery,knee popliteal arteries and the related branches.Related artery branch and silk thread ligation and broken.After the operation,the rats were kept in separate cages.2 days later,some of the rats showed lameness and cyanosis of the lower limbs.Part of a lower limb necrosis in rats.Thirty rats with lower limb ischemia but no necrosis were selected.The right foot of rats was sterilized with iodine,and the wound surface was made with a skin biopsy drill with a diameter of 5mm and a depth of 3mm.The chitosan biological protection of wound dressing evenly spray spray membrane function in experimental ulcer wound,the control group,saline spray once per day,for14 d.3,5,7,14 days after radiography,Image J Image software,the healing area and healing rate comparison and analysis,the two groups take different postoperative days ulcer line organization immunohistochemical,detection of Vascular Endothelial Growth Factor,Interleukin-2,Tumor Necrosis Factor,Endothelial Nitric Oxide Synthase and Basic Fibroblast Growth Factor protein positive expression.Results:The ulcer area of the experimental group was significantly smaller than that of the control group,and the healing rate of the experimental group on days 3,5,7 and 14 was significantly better than that of the control group(66.71±2.01 on days 3,78.12±1.24 on days 5,89.24±1.15 on days 7,100±0.00 on days 14).The control group at 3 days 54.29±3.26,5 days 64.53±2.55,7 days 71.13±1.44,14 days 82.81±1.95),P<0.05,the difference was statistically significant.Immunohistochemical tests of vascular endothelial growth factor,interleukin-2,tumor necrosis factor,endothelial nitric oxide synthase and basic fibroblast growth factor were performed on ulcerated tissues from different days.The results indicated that the positive expressions of vascular endothelial growth factor(205.32±29.38 in the experimental group and 151.52±16.29 in the control group)and basic fibroblast growth factor(290.53±45.63 in the experimental group and 199.86±17.31 in the control group)were high,and the differences were statistically significant(P<0.05).The results showed that chitosan complex could accelerate wound healing by inducing the expression of vascular endothelial cell growth factor and basic fibroblast growth factor.Conclusion:Chitosan and its compounds can promote the wound healing of ischemic ulcer of lower extremity,and the healing mechanism may be that chitosan can induce tissue repair,cell proliferation and promote angiogenesis.At present most of the in vitro experiment and clinical application of tip has a good application prospect in the treatment of diabetic foot ulcers.This study applies comparative study on the animal experiment,found that chitosan and its complexes by promoting the expression of Vascular Endothelial Growth Factor and Basic Fibroblast Growth Factor,promote the healing of lower limb ischemic ulcers.Chitosan and its complex clinical research for the treatment of lower limb ischemic ulcersObjective:Through the animal experiment and clinical application of chitosan dressings and the therapeutic effect of traditional treatment of lower limb ischemic ulcers,guiding role for the future treatment of lower limb ischemic ulcer.Methods:In May 2019 to January 2020,according to the standard for 30 cases of patients aged40 to 85 years old.Chitosan compound wound dressing was used in the experimental group,while ordinary gauze dressing was used in the control group.The age,sex,combined diseases and other general data of selected patients were compared,and SPSS19.0 was used to analyze whether the data had statistical significance.Radiography Image J Image analysis software observed after 7,14,21,28 days ulcer surface size,healing rate;The sterilized swab was placed at the bottom of the ulcer and marked parallel to the skin.The length obtained was the ulcer depth in mm(mm).The patient's degree of pain VAS score scale assessment.Results:A total of 30 patients completed the clinical trial in the clinical study.After statistical analysis,there was no statistically significant difference between the experimental group and the control group in terms of age,gender,combined diseases,etc.,with P>0.05.The healing rate of ulcer in the experimental group at 14,21 and 28 days after treatment was better than that in the control group(41.0±19.0,62.0±18.0,79.0±20.0,29.0±31.0,48.0±21.0,60.0±22.0),P<0.05,the difference was statistically significant.The ulcer depth on day 14,21 and 28 was better than that of the control group(4.27±3.13,3.35±2.26 and 2.11±1.68 in the experimental group on day 14,3.35±2.26 and 28,and 4.71±1.79,3.91±1.64 and 3.01±1.63 in the control group on day 14,21 and28),P<0.05,indicating statistically significant differences.VAS scores of the experimental group on days 7,14,21 and 28 were lower than those of the control group(2.98 ±1.05 on days 7,2.50±1.44 on days 14,2.19±1.01 on days 21,1.84±1.14 on days 28).In the control group,3.71±1.09 on day 7,3.61± 1.05 on day 14,3.31±1.16 on day 21,2.91±1.12 on day 28),P<0.05,the difference was statistically significant.Conclusion:Chitosan and its compound dressing can provide an "optimal microenvironment" for the wound surface of ischemic ulcer,effectively promote the healing of ischemic ulcer,and at the same time alleviate the pain of patients,which has good clinical application value.