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Objective:To evaluate the efficacy of botulinum toxin A injection therapy with ultrasound-guided for benign masseter hypertrophy.Methods:Twenty cases (40 sides) of masseter hypertrophy were injected with botulinum toxin A, among which 10 cases were taken as experimental group and the other 10 cases as control group. The experimental group had preoperative ultrasound examination to measure the thickness of masseter, and use ultrasound-guided precise injection during the operation, and then ultrasound recheck to measure the postoperative masseter thickness; The other 10 cases of control group adopt traditional 3-point injection method.Results:The masseter thickness of the two groups at different period of times after treatment was decreased ( P<0.001), the most obviously decrease happened 4-12 weeks after injection. The mean reduction was 26.8% at 4 weeks and 28.4% at 12 weeks after injection. Masseter muscle thickness recovered by 22% at 24 weeks and by 20% at 36 weeks. The average follow-up was 6.0±2.4 months with no serious complications occurred. In the control group, there was a partial masseter bulge in one case. The satisfactory rate of the patients in the experimental group was higher than that of the control group. Conclusions:Botulinum toxin A injection therapy with ultrasound-guided for benign masseter hypertrophy is an effective treatment, which is more accurate and effective than the traditional injection method.
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Objective To optimize the method of the directional differentiation of adipose-derived stem cells into keratinocytes.Methods Adipose-derived stem cells (ADSCs),separated by collagenase digestion method,were isolated and cultured.Then the expression of surface specific markers CD34,CD44 and CD90 were detected by flow cytometer.The effect of different induced mediums cultured for two weeks on the differentiation of ADSCs into KCs was demonstrated:Group 1,the DMEM supplied with 2％ FBS and 49％ supertant of KCs;group 2,KSFM medium;group 3,DMEM medium supplied with 10％ FBS and 5 μM ATRA;10％ FBS DMEM as the control group.Immunofluorescene staining was applied to detect the expression of keratin CK14 and F-actin.Results A flattened fibroblast-like morphology was observed in cells,the positive expression rate of CD34 was 0.08％,while those of CD44 and CD90 were 99％.The cells that could differentiate into osteoblasts and chondrocytes,indicated that the cells were ADSCs.There was no significant change in the cell morphology in the group 1 under the induction medium;about 10％ of the cells in group 2 were altered;the morphological changes were obvious in group 3,and approximately 20％ of the cells showed irregular polygon.The immunofluorescene staining of the cells in group 3 indicated that the cells showed cobblestone-like phenotype and an organized cytoskeletal network with dense actin fibers at the edges;some cells were positive for CK14.Conclusions ADSCs show higher induction rate under ATRA stimulation.
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Objective To investigate the efficacy and the nursing experience of vacuum sealing drainage (VSD) combined with topical oxygen therapy on healing of pressure ulcers in intensive care unit. Methods Totally 44 cases of patients in intensive care unit with pressure ulcers on stage Ⅲ and Ⅳbedsore, from May 2015 to October 2017, were divided into 2 groups according to the random number table.22 cases, as the control group, were treated with routine methods and VSD.22 cases, as the test group, were treated with topical oxygen therapy on basis of the treatment of control group, 10 days for a cycle. The effects of the two methods were compared according to the wound healing rate, the bacterial quantitative, the cell apoptosis rate and the capillary density after a treatment cycle. Results The average wound healing rates of the control group and the test group were (16.5±6.7)% and (26.2±5.6)% respectively, between which there was a significant difference (t=5.09, P＜0.01). Before treatment, the bacterial quantitative, cell apoptosis rate and capillary density in the control group were (2.7 ± 0.8) × 107CFU/g, (9.3±1.5)%, 13.43±3.21 respectively, and in the test group were (2.9±1.1)×107CFU/g, (10.1± 1.1)% , 11.51 ± 2.75, there was no significant difference between the two groups (all P>0.05). After treatment, the bacterial quantitative, cell apoptosis rate and capillary density in the control group were (4.9±1.4)×104CFU/g, (5.5±0.8)%, 38.64±10.14, and in the test group were (2.5±0.7)×104CFU/g, (2.9± 0.9)% , 41.09 ± 9.28. The differences before and after treatment in the control group were statistically significant (q=1 967.75, 3.51, 6.12, all P<0.01 or 0.05), and the differences before and after treatment in the test group were statistically significant (q=3 912.32, 5.22, 8.07, all P<0.01). There were significant differences in the bacterial quantitative and cell apoptosis rate between the two groups after treatment (q=3.85, 3.78, all P<0.01), however, there was no significant difference in vascular density (P>0.05). Conclusion The vacuum sealing drainage combined with topical oxygen therapy can enhance wound healing and control infection significantly, is a safe and effective therapeutic method.
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Smart dressings, which show obvious advantage and potential in wound treatment and real-time monitoring, attract widespread attention in recent years. Real-time and dynamic acquiring wound information is vital to the treatment and prognosis of wound. Further research on smart dressings is helpful for wound management, personalized treatment, and realization of medical application translation of health monitoring technology. In the article, we categorize smart dressings and conclude their functions according to the type of micro-environment information of wound gathered by smart dressings.
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Objective@#To investigate the efficacy and the nursing experience of vacuum sealing drainage (VSD) combined with topical oxygen therapy on healing of pressure ulcers in intensive care unit.@*Methods@#Totally 44 cases of patients in intensive care unit with pressure ulcers on stage Ⅲ and Ⅳ bedsore, from May 2015 to October 2017, were divided into 2 groups according to the random number table.22 cases, as the control group, were treated with routine methods and VSD.22 cases, as the test group, were treated with topical oxygen therapy on basis of the treatment of control group, 10 days for a cycle. The effects of the two methods were compared according to the wound healing rate, the bacterial quantitative, the cell apoptosis rate and the capillary density after a treatment cycle.@*Results@#The average wound healing rates of the control group and the test group were (16.5±6.7)% and (26.2±5.6)% respectively, between which there was a significant difference (t=5.09, P<0.01). Before treatment, the bacterial quantitative, cell apoptosis rate and capillary density in the control group were (2.7±0.8) ×107CFU/g, (9.3±1.5)%, 13.43±3.21 respectively, and in the test group were (2.9±1.1) ×107CFU/g, (10.1±1.1)%, 11.51±2.75, there was no significant difference between the two groups (all P>0.05). After treatment, the bacterial quantitative, cell apoptosis rate and capillary density in the control group were (4.9±1.4) ×104CFU/g, (5.5±0.8)%, 38.64±10.14, and in the test group were (2.5±0.7) ×104CFU/g, (2.9± 0.9)%, 41.09±9.28. The differences before and after treatment in the control group were statistically significant (q=1 967.75, 3.51, 6.12, all P<0.01 or 0.05), and the differences before and after treatment in the test group were statistically significant (q=3 912.32, 5.22, 8.07, all P<0.01). There were significant differences in the bacterial quantitative and cell apoptosis rate between the two groups after treatment (q=3.85, 3.78, all P<0.01), however, there was no significant difference in vascular density (P>0.05).@*Conclusion@#The vacuum sealing drainage combined with topical oxygen therapy can enhance wound healing and control infection significantly, is a safe and effective therapeutic method.
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Recently, researchers have focused on the micro-mechano-environment and the resulting mechanical cues which can regulate the morphology, structure, and function of cells. As a novel mechanotherapy, negative-pressure wound therapy (NPWT) has revolutionized the treatment of acute and chronic wounds. The effects of mechanics in use of NPWT has been noticed by researchers, and sporadic results have been reported, while the mechanisms of mechanosensitivity and mechanotransduction in affecting cell behaviors and promoting wound healing haven′t been elucidated yet. In this article, we review the progress about the relevant mechanical forces of NPWT and the mechanical effects on major repairing cells involved in wound healing, in order to provide references for the better understanding of mechanobiology of NPWT to better wound healing.
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BACKGROUND: Chitosan wound dressing has been extensively used in the treatment of wounds and burns, not only because of its bacteriastasis, hemostasis and promoting the wound healing, but also its good biocompatibility,biodegradability and biological functions.OBJECTIVE: To evaluate the efficacy and safety of chitosan wound dressing for deep second-degree burn, thereby providing clinical basis for its registration.METHODS: Sixty patients with deep second-degree burn were randomly allotted to two groups, and then subjected to the external application of chitosan wound dressing (experimental group) or chitosan biomedical dressing (control group),respectively. Then, the therapeutic efficacy was evaluated through healing time, recovering rate and pain scores, and the safety was evaluated through the incidence of adverse reactions and laboratory indexes before and after treatment.RESULTS AND CONCLUSION: There were no significant differences in the wound healing time [(21.23±6.84) days vs.(23.77±4.26) days], recovery rate and pain scores between the experimental and control groups at 14, 21 and 28 days after treatment (P > 0.05). The blood routine, liver function and kidney function indexes before and after treatment did not differ significantly between groups. Additionally, neither adverse nor severe adverse events occurred in the two groups.These results indicate that the therapeutic efficacy and safety of the chitosan wound dressing are equivalent to the control product in the treatment of deep second-degree burn.
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Objective Proper selection of reconstruction method is the key point to get a successful result in nasal reconstruction.The purpose of the article is to evaluate the results of repairing the partial nasal defect with different surgical strategies.Methods Different surgical methods were used according to the area and type of nasal defects of nasal defects,the different sub-unit of nasal de fects and the different tissue damage levels.Local skin flaps,auricular composite tissue flaps,nasolabial skin flaps and superficial temporal artery pedicle flaps were used in these patients.Results 23 cases suffering from partial nasal defects were repaired with flaps or tissue graft,including 4 auricular composite tissue flap,5 nasolabial skin flap,3 forehead island flap with a pedicle of superficial temporal vessels,7 local flap,and 1 skin graft.After 5-16 months of follow-up,the color and texture around the nose were basically consistent,the appearance of nose was satisfactory,and the postoperative effect turned out fine.Conclusions The method of surgical reconstruction of partial nasal defects should be considered carefully according to the area of nasal defects,sub-unit of nasal defects and the different tissue damage levels.
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Objective To study whether ferulic acid can promote healing on chronic ischemic wounds and its possible mechanisms.Methods 40 male New Zealand white rabbits were randomly divided into 4 groups:vaseline group,ischemic control group,5％ ferulic acid group and recombinant bovine basic fibroblast growth factor for external use (rb-bFGF) group.Gross wounds were carefully observed and HE staining was used to observe the wound healing and immumohistochemical staining to observe the expression of the VEGF and CD31.The RNA was extracted to detect the expression of VEGF and HIF-1a by real-time PCR.Results The general observation and the HE staining of each specimen 11 days after operation all indicated that the duration of wound healing of the 5 ％ ferulic acid group was similar to that of the rb-bFGF group and markedly shorter than the ischemic control group and the vaseline smear group.The result of the immunohistochemical staining indicated that the content of the VEGF and CD31 expression of the 5 ％ ferulic acid groups and the rb-bFGF group made lit tle difference,but there was markedly less VEGF and CD31 in ischemic control group and the vaseline smear group.The result of the PCR showed that expression level of VEGF and HIF-1α in the 5 ％ fer ulic acid group was similar to that in the rb bFGF group and the vaseline smear group,but was obviously more than that of the ischemic control group and the vaseline smear group (P ＜ 0.05).Conclusions Ferulic acid can promote angiogenesis by increasing VEGF and HIF-1α which are closely related to angiogenesis and then promote the healing of chronic wounds.
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<p><b>OBJECTIVE</b>To study the changes in the expression of large-conductance calcium-activated potassium (BKCa) channels in dorsal root ganglion (DRG) neurons after electrical injury in rats' sciatic nerves and its influence on sensory conduction function.</p><p><b>METHODS</b>One-hundred and thirty-six adult SD rats were divided into normal control group, sham electrical injury group, and 75, 100, 125 V electrical injury groups according to the random number table, with 8 rats in normal control group and 32 rats in each of the rest 4 groups. Rats in normal control group were routinely fed without any treatment. Blunt dissection of the sciatic nerves of left hind leg of rats was performed in sham electrical injury group, while sciatic nerves of left hind leg of rats in electrical injury groups were electrically injured with corresponding voltage. Eight rats of normal control group fed for one week, and 8 rats from each of the rest four groups on post injury day (PID) 3 and in post injury week (PIW) 1, 2, 3 respectively were collected to detect the paw withdrawal mechanical threshold (PWMT). In addition, rats of 100 V electrical injury group in PIW 1 were collected and intrathecally injected with NS1619 after former PWMT detection, and PWMT was detected per 30 minutes within three hours post injection. The rats in each group at each time point were sacrificed after PWMT detection. The DRG of L4 to L6 segments of spinal cord was sampled to observe the BKCa channels distribution with immunohistochemical staining and to detect the protein and mRNA expressions of BKCa channels with Western blotting and reverse transcription-polymerase chain reaction respectively. Data were processed with one-way analysis of variance, analysis of variance of factorial design, and SNK test.</p><p><b>RESULTS</b>(1) The PWMT values of rats in 75 and 100 V electrical injury groups on PID 3 and in PIW 1, 2, 3 were (5.8±0.6), (5.0±0.8), (4.2±0.3), (5.9±1.1) g; (5.3±1.3), (5.9±2.0), (4.5±2.7), (4.3±1.3) g, respectively, which were significantly lower than the value (s) in normal control group [(11.2±2.0) g] and sham electrical injury group [respectively (11.3±2.1), (12.0±2.0), (11.1±1.6), (10.3±2.1) g, with P values below 0.05]. The PWMT values of rats in 125 V electrical injury group decreased obviously on PID 3 and in PIW 1 [(6.1±1.6) and (5.7±1.7) g] as compared with the value (s) in normal control group and sham electrical injury group, and they were obviously increased in PIW 2 and 3 [(26.7±3.3) and (21.7±3.4) g] as compared with the value (s) of the rest 4 groups (with P values below 0.05). The PWMT of 100 V electrical injury group in PIW 1 firstly increased and then decreased within three hours post injection, which increased significantly at post injection minutes 30, 60, 90, 120 as compared with that before intervention [respectively (8.5±0.8), (9.7±1.2), (11.0±1.5), (8.6±0.8) g, with P values below 0.05]. (2) The positive expression of BKCa channels in large amount was observed in the cytoplasm and cytomembrane of neurons on the DRG of rats in normal control group and sham electrical injury group at each time point. The positive expression of BKCa channels in the cytoplasm and cytomembrane of neurons on the DRG of rats decreased over time in electrical injury groups, which was most obvious in 125 V electrical injury group. (3) There were no statistically significant differences in the protein expression of BKCa channels in DRG of rats among the five groups on PID 3 (with P values above 0.05). Compared with those in normal control group (0.477±0.027, 0.521±0.034, 0.475±0.022) and sham electrical injury group (0.511±0.025, 0.489±0.025, 0.483±0.032) in PIW 1, 2, 3, the protein expressions of BKCa channels in DRG of rats in 75, 100, 125 V electrical injury groups were decreased significantly (0.274±0.026, 0.202±0.019, 0.285±0.033; 0.253±0.022, 0.233±0.024, 0.203±0.017; 0.092±0.017, 0.095±0.021, 0.087±0.016, with P values below 0.05). The protein expressions of BKCa channels in DRG of rats in 125 V electrical injury group in PIW 1, 2, 3 were obviously lower than those in 75 and 100 V electrical injury groups (with P values below 0.05). (4) The mRNA expression levels of BKCa channels in DRG of rats in 75, 100, 125 V electrical injury groups on PID 3 and in PIW 1, 2, 3 were 0.326±0.021, 0.238±0.019, 0.291±0.022, 0.364±0.018; 0.264±0.020, 0.293±0.017, 0.243±0.023, 0.295±0.021; 0.134±0.023, 0.089±0.017, 0.074±0.018, 0.087±0.020, respectively, significantly decreased as compared with the level (s) in normal control group (0.581±0.051) and sham electrical injury group (0.603±0.045, 0.586±0.032, 0.614±0.045, 0.572±0.038), with P values below 0.05. The mRNA expression levels of BKCa channels in DRG of rats in 125 V electrical injury group at each time point were lower than those in 75 and 100 V electrical injury groups (with P values below 0.05).</p><p><b>CONCLUSIONS</b>The electrical injury in sciatic nerves results in reduction of the BKCa channels expression in rat's DRG of corresponding spinal segments, which plays a role in the pathological process of sensory conduction dysfunction.</p>
Subject(s)
Animals , Rats , Blotting, Western , Electricity , Ganglia, Spinal , Metabolism , Large-Conductance Calcium-Activated Potassium Channels , Metabolism , Random Allocation , Rats, Sprague-Dawley , Sciatic Nerve , Wounds and InjuriesABSTRACT
The differentiation of stem cells into target cells in a particular region is an important prerequisite for the organ construction and tissue engineering. The processes are multi-directionally regulated by the surface properties of biomaterials, and among them the influences of mechanical rigidity and surface morphology of biomaterials on morphological characteristics, focal adhesion assemblies, and cytoskeletal structure of cells are considered to be the most important factors in regulating the differentiation of stem cells into specific cell lineages. This review summarizes the progresses on this topic in the past few years, which may provide a reference to the design of the biomaterials in regenerative medicine and tissue engineering.
Subject(s)
Humans , Biocompatible Materials , Metabolism , Cell Differentiation , Cell Lineage , Musculoskeletal System , Cell Biology , Metabolism , Regenerative Medicine , Stem Cells , Cell Biology , Surface Properties , Tissue EngineeringABSTRACT
Objective To investigate the variation of the thioredoxin system (Trx),and the role of it in transient out-ward potassium current (Ito) channels in left ventricular myocytes of diabetes mellitus (DM) in rats. Methods Forty-five SD rats were divided into DM group and control group. DM group were treated with streptozotocin (STZ) to induce DM model. The values of left ventricular end diastolic diameter (LVEDD), end-systolic diameter (LVESD), fractional shortening (LVFS), ejection fraction (LVEF) and heart rate (HR), QRS duration and corrected QT (QTc) interval were detected by echocardiogra-phy (UCG) and electrocardiogram (ECG) in two groups. The left ventricular myocardial tissue samples were taken to detect the Trx,glutaredoxin (GRX),thioredoxin reductase (TrxR) and glutathione reductase (GR) by using UV spectrophotometer. The level of free thiol (P-SH) of total cardiac protein was detected by 5, 5′-dithio-bis-2-nitrobenzoic acid method. Ito of the cardiomyocytes was recorded by whole-cell patch-clamp method. After being incubated in vitro with insulin(Ins), treated with TrxR inhibitor-auranofin(AF) and 13-cis-retinoic acid(RA), the changes of Ito of the cardiomyocytes were observed. Results Compared with control group, the values of heart rate (HR), left ventricular minor axis decurtaion rate (LVFS), left ventricular ejection fraction (LVEF) and TrxR were lower in DM group. The values of LVEDD, LVESD, QRS and QTc inter-vals, Trx, Grx and P-SH were higher in DM group than those of control group. Ito density was significantly higher in DM+Ins group than that of DM group, Ins+RA group and Ins+AF group when the stimulation voltage ≥ 0 mV (P ＜ 0.05). Conclusion The impaired Trx system in diabetic rat myocardium was the electrophysiological basis of the reduced ventric-ular function and arrhythmia. And Ins was able to reverse the decreased Ito of cardiomyocytes in DM rats.
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Objective To evaluate the long term effect of acellular allogeneic nerve grafting combined with exogenous basic fibroblast growth factor (bFGF) in peripheral nerve repair. Methods Sixteen big-ear Japanese rabbits were divided into experimental and control groups randomly. In the experimental group, 3 cm-long acellular allogeneic nerves from New Zealand rabbit were used to bridge the rabbit tibial nerve defects; and 1 ml bFGF solution was given from the second day once daily for 2 weeks and twice a week for another 6 weeks after surgery. In the control group, normal saline solution was given. Morphological and functional results were evaluated 20 weeks after the nerve repair. Results The recovery rates of the evoked potential and the nerve conduction velocity in the experimental group were 67.59%?29.63% and 59.79%?21.11%, respectively, significantly higher than that (49.07%? 15.74% and 36.85%?18.69% respectively) in the control group (P
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Objective To observe the granule tissue remodeling under neoepithelium in minitype pigs' full thickness dermal wounds and discuss the relation between the remodeling and possible ulcers or scars. Methods After the establishment of eight full-thickness dermal wound models with the diameter of 4 cm on the back of six minitype pigs, the specimens were collected from wound edge and wound center immediately, 3, 6, 9, 12, 15, 20, 25, 30 and 45 days, respectively after injury for HE staining, immunohistochemical staining and Van Gieson staining and then observed under light microscope to count the cell number, fibroblasts and vascular endothelial cells as well as evaluate the quantity and arrangement of collagens. Results The mean wound healing time was (29.3?1.8) days. After 9-25 days, the granule tissues in the wound center contained more cells, fibroblasts, collagen and vascular endothelial cells than those under neoepithelium of wound edge (P 0.01). Meanwhile, the collagen quantity and arrangement style of granule tissues under neoepithelium during wounds healing (12-30 days) assembled those under neoepithelium 15 days after wound healing. Conclusion Granule tissue remodeling exists during the healing of full thickness dermal wound.
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Objective To discuss the therapeutic effects and safety of external ultrasound liposuction to adipose tissue of lower extremities and to summarize the operative techniques. Methods According to the requests of 81 patients, external ultrasound liposuction were performed for them on thighs (n=60), and legs (n=21). It was that the volumes of anesthetic drugs and pure fat as well as the variations of body contour between preoperation and one to three months after operation in every area were recorded. Results Fat aspiration volume in thighs was 3673ml per person with the highest 6100ml. The scale of the circumference of thighs decrease (4.65?1.10)cm with the highest 12.5 cm. In legs, fat volume was 650ml per person with the highest 1200ml, scale decrease (3?1.02) cm with the highest 9cm. Patients had less blood loss, less pain and discomfort with even skin appearance and without severe complications. In the course of operation, knowing well the anatomical character of lower extremities, injecting the anesthetic drugs completely, using appropriate ultrasound time, and sucking in uniform layer were all crucial factors to guarantee the success of the operation. Conclusion External ultrasound liposuction is a safe, effective body contour remodeling operation in lower extremities. Skillful operator is a very important element to successful operation.
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Objective To evaluate the promoting effect by bFGF on nerve regeneration following acellular allogeneic nerve grafting,and the effects of various concentration of bFGF on axon growth. Methods The animals were divided into 1 000U/ml, 500U/ml, 250U/ml,100U/ml and normal saline groups. Immunohistochemistry staining of neurofilament-160 and S-100 was used to show the length of axonal growth and Schwann cell infiltration 10 days after the surgery. Results The average distance of regenerated nerve fibers in the high dose groups (1 000U/ml and 500U/ml) was longer than that in the normal saline control group;but there was no difference between the low dose groups (250U/ml and 100U/ml) and the control group. Conclusion Early use of bFGF when acellular allogeneic nerve grafted to bridge peripheral nerve defect may obviously promote axon growth speed.
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Objective To evaluate the biocompatibility of four kinds of polyurethane sponges made in China. Methods According to ASTM Standards for Medical Devices of America, polyurethane sponges are used to perform such biological tests as cytotoxicity test, acute toxicity test, pyrogenic reactions test, stimulation test of conjunctiva and cornea, sensitization test. The data are analyzed and evaluated according to the criterion. Results Reaction scales of these polyurethane sponges in cytotoxicity are 0 or 1 level. No toxicity effects and pyrogenic reactions are observed in vivo test. No conjunctiva and cornea irritation reactions and no sensitization reactions are found. Conclusions The four kinds of polyurethane sponges have high biocompatibility and can become ideal dressings of Vacuum-Assisted Closure.
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Objective To evaluate the biocompatibility of ZSM-5 zeolite and provide an experimental basis for developing the first-aid hemostatic agent.Methods According to Chinese evaluation standards on medical devices and biological tests,the cytotoxicity in vitro,hemolysis test,acute toxicity of system,pyrogen test,intracutaneous stimulation,sensitization and micronucleus test were studied in ZSM-5 zeolite.In order to find out the side-effect of the zeolite granules' remains left in the wounds to body,muscle implantation test was studied.Results There were no obvious cytotoxity,hemolysis reaction.Acute tocicity,pyrogen reaction,intraeutaneous stimulation,sensitization and potential mutagenesis in themicronucleus test were observed.Their results were a11 consistent with the Chinese biological evaluation of medical devices.Obvious inflammatory reaction was observed when ZSM-5 zeolite was implanted in muscle for 12 weeks.Conclusion The ZSM-5 zeo1ite has reliable biocompatibility.But zeolite can cause inflammatory reaction when it is remained in the wound surface for long term.
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Objective To test the effect of negative pressure on the rate of skin donor site re-epithelialization in pig model.Methods Five pigs were selected for this study,and two split-thickness skin graft defects were harvested from the back of each animal.Half of the donor sites were treated with 120 mmHg negative pressure as the experimental group for 10 days and half were treated with vaseline gauze as the control.Changes in each wound were assessed every two days.Results The rate of re-epithelialization increased significantly.The donor sites healed after 4 to 6 days of negative pressure treatment, 2 to 4 days earlier than the control group.The level of inflammatory reaction occurring in wounds treated with negative pressure appeared less severe than that in wounds treated with vaseline gauze.Negative pressure could facilitate cell proliferation.The ratios of S,G2 and M phase increased significantly,and higher expression of PCNA was observed and detected in hair hollicle epithelium,regenerative basal cells and glandular epithelium on day 4 and 8 after negative pressure treatment.Conclusion Negative pressure could significantly increase the rate of skin donor site re-epithelialization