Wound repair has its inherent pathophysiological mechanism, presenting a complex network regulation. However, these contents are not detailed exhaustively or systematically in the medical undergraduate education system in China and even the world. Therefore, it is difficult for those clinicians who are not engaged in wound repair related research to fully understand the mechanism of wound repair and its relationship with the clinical process. To provide a reference for clinical work, this article summarizes the sequential, local, time-bounding characteristics of wound healing related to the clinical practice through the understanding of the relevant mechanisms of wound repair.

Burn patients with large area of skin defect are prone to cause wound infection, severe fluid loss, and hypermetabolism, etc, which lead to sequential dysfunction of multiple systems and easily induce severe systemic infections and sepsis. At present, sepsis has been the leading causes of death in severe burn patients, and its early diagnosis and timely treatment are critical for successful treatment of patients. As burn sepsis has unique pathophysiological characteristics, the diagnostic criteria for general sepsis lack specificity for burn sepsis. Therefore, to understand the pathogenesis of burn will help deepen the understanding of the diagnostic system and interventional way of burn sepsis, thus developing more precise and intelligent therapeutic strategy.

With the rapid development of modern treatment methods for chronic wounds, it plays a positive role in the clinical treatment of this kind such disease. However, the traditional treatment methods for chronic wounds also have potential advantages. We should conduct in-depth research on these methods to improve the relevant understanding and actively apply these methods in clinic to exert their therapeutic role. This article discusses the application of wound cleaning, conservative debridement, traditional Chinese medicine, maggot treatment, and enzymatic debridement in the treatment of chronic wounds.

Objective To investigate the effects of medical maggot excretions/secretions (ES) on neutrophils phagocytosis and bactericidal effect in patients with diabetic foot ulcer (DFU). Methods The experimental research method was used. Thirty DFU patients (16 males and 14 females, aged (64±7) years)who were admitted to the Diabetes Foot Center, the Department of Endocrinology of Air Force Hospital of Eastern Theater Command from June to December 2020 and met the inclusion criteria were recruited. Discontinuous percoll gradient centrifugation method was used to separate the neutrophils. Cells from each patient were enrolled into normal saline group and maggot ES group (30 wells in each group), respectively; sterile normal saline and ES with a final mass concentration of 357 μg/mL (the same as below) were added, respectively. After 1 and 2 hour(s) of culture, the phagocytosis rate and phagocytic index of cells were observed and counted under Wright's staining. Ten patients were selected, then the cells of each patient were enrolled into

+neutrophils group and

+neutrophils+maggot ES group (10 wells in each group) and were treated corresponding, respectively.

alone group and

+maggot ES group (10 wells in each group) were set up respectively;

+RPMI 1640 culture medium+sterile normal saline and

+RPMI 1640 culture medium+maggot ES were added, respectively. After 2 hours of culture, the number of viable bacteria colony was counted by plate colony number method. Six, six, and three patients were selected respectively, and the cells of each patient were respectively enrolled into maggot ES group and normal saline group (6, 6, and 3 wells in each group, respectively) and treated accordingly. After 6 hours of culture, real-time fluorescent quantitative reverse transcription polymerase chain reaction was used to detect the mRNA expressions of interleukin 1β (IL-1β), IL-6, and lysozyme in cells, the content of IL-1β and IL-6 in cell culture supernatant were determined by enzyme-linked immunosorbent assay, and the positive cells expressing lysozyme were observed with immunofluorescence method. Data were statistically analyzed with one-way analysis of variance, paired sample

test, least significant difference test, and Wilcoxon rank sum test. Results After 1 hour of culture, the phagocytosis rate and phagocytic index of cells in maggot ES group (53.5% (49.7%, 58.0%) and 3.18 (2.96, 3.32)) were similar to 52.0% (47.5%, 55.2%) and 3.15 (2.96, 3.25) of normal saline group (

=-1.701, -1.092,

>0.05). After 2 hours of culture, the phagocytosis rate and phagocytic index of cells in maggot ES group (70.0% (66.7%, 72.0%) and 4.47 (4.22, 4.96)) were significantly higher than 58.0% (55.0%, 60.0%) and 4.11 (3.52, 4.24) in normal saline group (

=-4.786, -4.279,

<0.01). After 2 hours of culture, the number of viable bacteria colony in

+neutrophils group was significantly lower than that in

alone group (

<0.01), and the number of viable bacteria colony in

+neutrophils+maggot ES group was significantly lower than that in

+maggot ES group and

+neutrophils group (

<0.01). After 6 hours of culture, the mRNA expressions of IL-1β, IL-6, and lysozyme of cells in maggot ES group were significantly higher those in normal saline group (

=-3.279, -4.273, -4.763,

<0.05 or

<0.01); the concent of IL-1β and IL-6 in cell culture supernatant of maggot ES group were significantly higher than those of normal saline group (

=-9.526, -6.447,

<0.01); there were significantly more positive cells expressing lysozyme in maggot ES group than in normal saline group. Conclusions Maggot ES can enhance the phagocytosis and bactericidal effect of neutrophils on Pseudomonas aeruginosa by promoting the production of neutrophils immune defense related cytokines and lysozyme in DFU patients.

Objective To observe the effect of interleukin-6 (IL-6) on the phenotype and function of human umbilical vein endothelial cells (HUVECs) and explore the role of IL-6 in the process of endothelial-to-mesenchymal transition (EndMT). Methods The experimental research method was used. Fresh umbilical cord discarded after normal maternal delivery was collected. On the second day of the primary cell isolation and cultivation, the cell morphology was observed under inverted phase contrast microscope. HUVECs of the 4th passage were identified by immunofluorescence method, and 2 batches of HUVECs ofthe 3rd to 5th passages were used for the subsequent experiments. The first batch of cells were divided into 6 groups according to the random number table (the same below): blank control group, 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group. The second batch of cells were divided into 4 groups: blank control group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group,and 50 ng/mL IL-6 group; the cells in blank control group was cultured with complete culture medium only, while the cells in the other groups were added with IL-6 of the corresponding final mass concentrations.Cells from the 1st batch were cultured for 72 hours after grouping, the morphology of HUVECS in the 6 groups was observed under inverted phase contrast microscope. At 72 h after grouping culture, the positive expressions of coagulation factor Ⅷ and α vascular smooth muscle actin (α-SMA) in HUVECs in the 6 groups were detected by immunofluorescence method, and the ratio of the number of double positive cells to the number of coagulation factor Ⅷ positive cells (the ratio of double positive cells for short) was calculated, with 6 samples per group; mRNA expression levels of vascular endothelial cadherin and α-SMA of HUVECs in 6 groups were detected by reverse transcription-polymerase chain reaction, with 3 samples per group.Cells from the 2nd batch were cultured 72 hours after grouping, the protein expression levels of vascular endothelial cadherin, α-SMA, and type Ⅰ collagen in the 4 groups were detected by Western blotting, with 3 samples per group. Data were statistically analyzed with one-way analysis of variance and Bonferroni correction. Results On the 2nd day after isolation and cultivation, the primary cells were in short spindle shape or polygon, cells of the 4th passage were identified as HUVECs by immunofluorescence method. At 72 hours of culture after grouping, the cells from the 1st batch in the 6 groups changed to long spindle shape morphologically along with the increase of IL-6 concentration, the intercellular connections decreased or disappeared with the gap between cells becoming larger. At 72 h after grouping culture, compared with that inblank control group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (

<0.01); compared with that in 5 ng/mL IL-6 group, the ratio of double positive cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly increased (

<0.01); compared with that in 10 ng/mL IL-6 group, the ratio of double positive cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly increased (

<0.01); the ratio of double positive cells in 100 ng/mL IL-6 group was significantly increased compared with those in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group (

<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group, 50 ng/mL IL-6 group, and 100 ng/mL IL-6 group were significantly decreased (

<0.01 or

<0.05); compared with that in 5 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (

<0.01); compared with that in 10 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (

<0.01); compared with that in 25 ng/mL IL-6 group, the mRNA expression levels of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group and 100 ng/mL IL-6 group were significantly decreased (

<0.01). At 72 h after grouping culture, compared with that in blank control group, the mRNA expression levels of α-SMA of cells in 5 ng/mL IL-6 group, 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, 50 ng/mL IL-6, group, and 100 ng/mL IL-6 group were significantly increased (

<0.05 or

<0.01). Cells from the 2nd batch were cultured for 72 hours after grouping. Compared with 1.391±0.026 in blank control group, the protein expressions of vascular endothelial cadherin of cells in 10 ng/mL IL-6 group (1.185±0.063), in 25 ng/mL IL-6 group (0.717±0.078), and in 50 ng/mL IL-6 group (0.239±0.064) were significantly decreased (

<0.05); compared with that in 10 ng/mL IL-6 group, the protein expressions of vascular endothelial cadherin of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly decreased (

<0.01); compared with that in 25 ng/mL IL-6 group, the protein expression of vascular endothelial cadherin of cells in 50 ng/mL IL-6 group was significantly decreased (

<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expression levels of α-SMA of cells in 10 ng/mL IL-6 group, 25 ng/mL IL-6 group, and 50 ng/mL IL-6 group were significantly increased (

<0.01); compared with that in 10 ng/mL IL-6 group, the protein expression levels of α-SMA of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (

<0.01). At 72 h after grouping culture, compared with that in blank control group, the protein expressions of type Ⅰ collagen of cells in 25 ng/mL IL-6 group and 50 ng/mL IL-6 group were significantly increased (

<0.05). Conclusions After IL-6 treatment, the phenotype and function of HUVECS showed the characteristics of mesenchymal cells in a concentration-dependent manner. The inflammatory factor can promote the process of EndMT, and become one of the important factors regulating the mechanism of tissue fibrosis.

Objective To investigate the status and influencing factors of skin cleaning outside wound (hereinafter referred to as skin) in adult trauma patients. Methods A multicenter cross-sectional investigation was conducted. From September 1 to 30, 2020, a total of 952 adult trauma patients who met the inclusion criteria were admitted to wound care clinics or trauma surgery wards of 13 military or local Grade Ⅲ Level A hospitals, including the General Hospital of the Eastern Theater Command of People's Liberation Army and the Army Medical Center, etc. A self-designed questionnaire on cleaning status of skin in trauma patients was released through the "questionnaire star" website to investigate basic information such as gender, age, education level, living status, and self-care ability, trauma information such as cause of injury, wound duration, trauma site, trauma depth, wound pain, wound peculiar smell, and wound cleaning solution, and skin cleaning status after injury such as whether to clean or not, cleaning method, cleaning frequency, cleaning duration in each time, or reasons for not cleaning. The patients who cleaned skin regularly after injury were included in cleaning group, and the other patients were included in no cleaning group. The basic information, trauma information, and skin cleaning status after injury of patients in 2 groups were investigated. Data were statistically analyzed with chi-square test, and binary multivariate logistic regression analysis was performed on indicators with statistically significant differences between the two groups to screen the independent influencing factors of skin cleaning in trauma patients. Results A total of 952 questionnaires were received, and the recovery rate was 100%. Three invalid questionnaires were eliminated, and 949 valid questionnaires were obtained, with an effective rate of 99.68%. In 949 patients, there were 461 (48.6%) males and 488 (51.4%) females, aged 18-100 (50±18) years. Most patients were less than 60 years old, lived with their families, and could take care of themselves completely. Nearly half of the patients were with junior high school or below education level. The main causes of injury were sharp cutting injury and falling injury, the wound duration was 2-365 days, most of the injured parts were limbs and trunk, the wound depth was mostly full-thickness injury, and most patients had wound-related pain and no peculiar smell and used 5 g/L iodophor to clean the wound. Totally 684 (72.1%) patients cleaned their skin after injury, mainly by scrubbing with warm water, the cleaning frequency was mainly once or twice a week, and the cleaning time was mainly 10 or 15 min for each time. Totally 265 (27.9%) patients didn't clean their skin after injury, and the main causes for not cleaning were following the doctor's advice, followed by worrying about wound infection and loss of self-care ability. There were significantly statistical differences in constituent ratios of education level, self-care ability, cause of injury, wound pain, and wound peculiar smell of patients in 2 groups (

²=12.365, 24.519, 22.820, 9.572, 92.342,

<0.01). Education level, self-care ability, cause of injury, wound pain, and wound peculiar smell were potential influencing factors of skin cleaning in patients. Binary multivariate logistic regression analysis showed that self-care ability, wound pain, and wound peculiar smell were independent influencing factors of skin cleaning in patients (odds ratio=1.51, 0.52, 3.72, 95% confidence interval=1.08-2.12, 0.42-0.89, 2.66-5.22,

<0.05 or

<0.01). Conclusions Self-care ability, wound pain, and wound peculiar smell are independent influencing factors of skin cleaning in adult trauma patients.

Objective To evaluate the clinical effects of 5-fluorouracil in different mass concentrations combined with triamcinolone in the treatment of keloids. Methods From March 2018 to March 2019, 29 patients with 31 keloids receipted in the Department of Plastic Surgery of Fujian Medical University Union Hospital, 11 patients with 20 keloids receipted in the Department of Dermatology of Pingtan Comprehensive Experimental Area Hospital, and 9 patients with 9 keloids receipted in the Fuzhou Heisey-Dea Aesthetic Clinic were included in this prospectively randomized control study, with 27 males and 22 females, aged (30±9) years. According to the random number table, the keloids were divided into low mass concentration group (19 keloids, 17 patients), medium mass concentration group (21 keloids, 19 patients), and high mass concentration group (20 keloids, 17 patients). Then 5-fluorouracil at mass concentrations of 0.5, 5.0, and 12.5 mg/mL combined with triamcinolone acetonide were injected respectively, once every 4 weeks, for a total of 3 times. Before the first treatment and in 3 months after the last treatment, the appearance of keloids was evaluated by Vancouver Scar Scale (VSS) and pain and pruritus of keloids were evaluated by Visual Analogue Scale (VAS). Then the score differences before and after the treatment were calculated. In 6 months after the last treatment, the patients' efficacy satisfaction was evaluated by efficacy satisfaction rating scale. Adverse reactions during the treatment were recorded. In the follow-up of one year after the last treatment, the recurrence rates of keloids were counted. Data were statistically analyzed with chi-square test, one-way analysis of variance, paired sample

test, least significant difference

test, Wilcoxon rank sum test, Kruskal-Wallis rank sum test, or Fisher′s exact probability test. Results Before the first treatment, the appearance VSS scores of appearance of keloids in the three groups were similar (

0.039,

>0.05). In 3 months after the last treatment, the appearance VSS scores of keloids in low mass concentration group were significantly higher than those in medium mass concentration group and high mass concentration group (

=2.267, 4.086,

<0.05 or

<0.01). In 3 months after the last treatment, the appearance VSS scores of keloids in low mass concentration group, medium mass concentration group, and high mass concentration group were significantly decreased compared with those before the first treatment (

=18.222, 44.272, 22.523,

<0.01). The differences of appearance VSS scores of keloids in low mass concentration group before and after treatment were significantly lower than those in medium mass concentration group and high mass concentration group (

=-4.096, -6.357,

<0.01), and the differences of appearance VSS scores of keloids in medium mass concentration group before and after treatment were significantly lower than those in high mass concentration group (

=-2.368,

<0.05). Before the first treatment, the pain and pruritus VAS scores of keloids in the three groups were similar (

²=0.149,

>0.05). In 3 months after the last treatment, the pain and pruritus VAS scores of keloids in low mass concentration group were significantly higher than those in medium mass concentration group and high mass concentration group (

=2.191, 4.386,

<0.05 or

<0.01), and the pain and pruritus VAS scores of keloids in medium mass concentration group were significantly higher than those in high mass concentration group (

=2.276,

<0.05). In 3 months after the last treatment, the pain and pruritus VAS scores of keloids in medium mass concentration group and high mass concentration group were significantly decreased compared with those before the first treatment (

-3.904, -3.844,

<0.01). The differences of pain and pruritus VAS scores of keloids in low mass concentration group before and after treatment were significantly lower than those in medium mass concentration group and high mass concentration group (

-4.265, -6.104,

<0.01). In 6 months after the last treatment, the efficacy satisfaction scores of the corresponding patients of keloids were (88±8) points in high mass concentration group, which were significantly higher than (76±8) points in medium mass concentration group and (60±8) points in low mass concentration group (

=-3.820, -6.675,

<0.01), and the efficacy satisfaction scores of the corresponding patients of keloids in medium mass concentration group were significantly higher than those in high mass concentration group (

=-2.984,

<0.05). There was only statistically significant difference in pain within the 3 groups (

<0.01). In the follow-up of one year after the last treatment, the recurrence rate of keloids in high mass concentration group was significantly lower than that in low mass concentration group (

²=8.313,

<0.01), and the recurrence rate of keloids in medium mass concentration group was similar to the recurrence rates in low mass concentration group and high mass concentration group (

>0.05). Conclusions After treating keloids with high mass concentration of 5-fluorouracil combined with triamcinolone acetonide, the symptoms were significantly improved, the efficacy satisfaction of patients was increased, with no obvious adverse reactions but long lasting efficacy. Their overall effects are better than treatment using medium and low mass concentrations of 5-fluorouracil, which is worthy of clinical promotion.

Objective To investigate the effects of positive end-expiratory pressure (PEEP) setting of mechanical ventilation guided by esophageal pressure in the treatment of patients with traumatic craniocerebral injury combined with acute respiratory distress syndrome (ARDS). Methods The retrospective cohort study was conducted. From June 2016 to June 2018, 55 patients with traumatic craniocerebral injury combined with ARDS who met the inclusion criteria were admitted to Zhengzhou Central Hospital Affiliated to Zhengzhou University. According to PEEP setting method, 28 patients were allocated to esophageal pressure group (17 males and 11 females, aged (40±13) years) and 27 patients were allocated to PEEP-fractional concentration of inspired oxygen (FiO₂) table group (18 males and 9 females, aged (38±10) years). Patients in the 2 groups were treated with mechanical ventilation guided by lung protective ventilation strategy, and the optimal PEEP at 0 (immediately), 24, 48, and 72 h after treatment was determined according to esophageal pressure and PEEP-FiO₂ table, respectively. The mechanical ventilation parameters in the 2 groups were adjusted according to the optimal PEEP. The transpulmonary end-expiratory pressure, pulmonary compliance, oxygen index, central venous pressure, mean arterial pressure, and intracranial pressure at 24, 48, and 72 h after treatment were recorded. Data were statistically analyzed with analysis of variance for repeated measurement, chi-square test, independent sample

test, and Bonferroni correction. Results The optimal PEEP of patients in esophageal pressure group at 0, 24, 48, and 72 h after treatment was (12.4±3.9), (11.2±3.5), (13.4±2.6), and (13.2±3.6) cmH₂O (1 cmH₂O=0.098 kPa), respectively, which was significantly higher than (8.2±2.5), (7.4±2.2), (8.3±2.3), and (8.5±2.5) cmH₂O in PEEP-FiO₂ table group, respectively (

=4.702, 4.743, 7.849, 5.623

0.01). The transpulmonary end-expiratory pressure and pulmonary compliance at 24, 48, and 72 h after treatment and oxygen index at 48 and 72 h after treatment of patients in esophageal pressure group were significantly higher than those in PEEP-FiO₂ table group (

=17.852, 20.586, 19.532, 4.752, 5.256, 7.446, 2.342, 4.178,

<0.05 or

<0.01). The central venous pressure of patients in esophageal pressure group at 24, 48, and 72 h after treatment was significantly higher than that in PEEP-FiO₂ table group (

=12.632, 5.247, 8.994,

<0.01), and there was no statistically significant difference in mean arterial pressure of patients between the 2 groups at 24, 48, and 72 h after treatment (

>0.05). The intracranial pressure of patients in esophageal pressure group was higher than that in PEEP-FiO₂ table group at 24, 48, and 72 h after treatment, but there was no statistically significant difference between the 2 groups (

>0.05). Conclusions For patients with traumatic craniocerebral injury combined with ARDS, the optimal PEEP can be set under the guidance of esophageal pressure method, and the mechanical ventilation parameters adjusted according to the optimal PEEP can improve lung compliance and accelerate recovery of lung function more effectively, with no adverse effect in mean arterial pressure and intracranial pressure.

Objective To explore the clinical effects of anterolateral thigh perforator flap with sensory nerves in repairing the plantar skin and soft tissue defects. Methods From January 2016 to March 2019, 13 male patients with plantar skin and soft tissue defects were admitted to the Department of Foot and Ankle Surgery of Ruihua Affiliated Hospital of Soochow University, aged 27 to 73 years. The retrospective cohort study was conducted. The wounds of 4 patients underwent 2 times of debridement. The wounds of 9 patients underwent 1 time of debridement and 1 or 2 time(s) of vacuum sealing drainage. Then all the wounds of patients were repaired with flaps when the wounds were clean and dry with no purulent exudation and were negative in secretion culture. The wound areas of this group of patients after wound debridement were 13.0 cm×5.5 cm to 36.0 cm×10.5 cm, and the wounds were repaired with anterolateral thigh perforator flaps with sensory nerves with area of 14 cm×6 cm to 37 cm×11 cm. The wound of 1 patient was repaired with a bilobed flap. The oblique or descending branch of the lateral circumflex femoral artery and its accompanying vein in the flap were anastomosed with the posterior tibial artery and its accompanying vein or the medial plantar artery and its accompanying vein in recipient sites. The lateral femoral cutaneous nerve in the flap was anastomosed with the recipient saphenous nerve or medial plantar cutaneous nerve. The donor sites were directly sutured. The survival of flaps and the healing of wounds in the donor and recipient areas were recorded, and the ulcers of the plantar repaired flap were followed up for 3 months after operation. The sensory function of the flap was evaluated by the sensory evaluation standard of British Medical Research Council (BMRC), and the ankle and foot function score system of American Orthopedic Foot and Ankle Society (AOFAS) was used for comprehensive functional evaluation at the last follow-up. Results All the 14 flaps in 13 cases survived, and venous crisis occurred in two cases and the flaps survived smoothly after the venous re-anastomosis. One patient developed deep tissue infection after being discharged and was healed after secondary debridement. The donor and recipient areas of the remaining patients healed well. The patients were followed up for 6 to 18 months, the shape of flaps was slightly bloated in 5 patients, and the shape and texture of flaps in the other 8 patients were good. Six patients had ulcers in flaps at 3 months of follow-up after operation, which were healed after stopping weight-bearing activities. At the last follow-up, little linear scar hyperplasia could be seen in the donor site of patients; the BMRC sensory function evaluation results were S₁ grade in 4 cases, S₂ grade in 7 cases, and S₃ grade in 2 cases; the AOFAS scores were excellent in 3 cases, good in 7 cases, fair in 2 cases, and poor in 1 case. Conclusions The anterolateral thigh perforator flaps with sensory nerves can repair the plantar skin and soft tissue defects with the donor sites directly sutured and good shape of flaps, which provide a good treatment method for the recovery of plantar proprioceptive sensation and weight-bearing function.

Objective To explore the effects and mechanisms of polycaprolactone-cellulose acetate (PCL-CA) nanofiber scaffold loaded with rat epidermal stem cells (ESCs) on wound healing of full-thickness skin defects in rats. Methods The experiment research method was applied. The primary ESCs were isolated from 1-3 d old Sprague-Dawley (SD) rats (undefined gender) by rapid adherent method and cultured by rapid adherent method. ESCs of the first passage were used for the subsequent experiments after the positive expressions of integrin β₁ and cytokeratin 19 (CK19) in primary cells were identified respectively by flow cytometey and immunofluorescence method. PCL-CA nanofiber scaffolds with polycaprolactone and cellulose acetate as components were prepared by electrospinning technique. The topological structure of the nanofiber scaffolds was determined and the diameter of 25 fibers was measured by scanning electron microscope. The constructed PCL-CA nanofiber scaffolds were used as the culture substrate for ESCs, which were cultured in keratinocytes (KCs) medium to construct ESCs-nanofiber scaffold complex (hereinafter referred to as ESCs scaffold). After 3 days of culture, the morphology of ESCs in the scaffold and their relationship was observed by scanning electron microscopy. The ESCs in ESCs scaffold were set as PCL-CA nanofiber scaffold group, and the ESCs cultured with KCs medium in culture dishes coated with type Ⅳ collagen were set as type Ⅳ collagen group. Western blotting was used to detect the protein expression level of CK19 in ESCs in the two groups after 3 days of culture (

=3). The protein expressions of CK19 and proliferating nuclear antigen (PCNA) in ESCs in the two groups were detected by immunofluorescence method after 7 days of culture. A circular full-thickness skin wound of about 2 cm in diameter was prepared on both left and right sides of the back of 15 male SD rats aged 6-8 weeks. The rats were then equally divided into blank control group without implantation, scaffold alone group implanted with PCL-CA nanofiber scaffold, and ESCs scaffold group implanted with ESCs scaffold which were constructed after 3 days of culture according to the random number table. The percentage of wound areas on post injury day (PID) 3, 7, 14, and 21 was calculated (

=5). The new skin tissue at the wound edge was collected on PID 21, the wound healing quality was evaluated by Masson staining, and the protein expression levels of Notch1, Jagged1, and Hes1, which are key proteins of Notch signaling pathway, were detected by Western blotting (

=3). Data were statistically analyzed with one-way analysis of variance, one-way analysis of variance, analysis of variance for repeated measurement, independent sample

test, and Bonferroni correction. Results The constructed PCL-CA nanofiber scaffolds had a porous, mesh-like, and multilayered three-dimensional structure, in which the surface of the fibers was smooth and non-porous, and the fiber diameter was (383±24) nm. The ESCs in ESCs scaffold showed intact cellular structures and were tightly attached to the scaffold after 3 days of culture. The cells were interconnected and fully extended on the surface of the scaffold to form a membrane. After 3 days of culture, the protein expression level of CK19 of ESCs in PCL-CA nanofiber scaffold group was significantly higher than that in type Ⅳ collagen group (

=24.56,

<0.01). After 7 days of culture, compared with those in type Ⅳ collagen group, there was no significant change in the proportion of PCNA positive cells of ESCs in PCL-CA nanofiber scaffold group, while the proportion of CK19 positive cells was higher. On PID 3, 7, 14, and 21, the percentages of wound areas of rats in ESCs scaffold group were (78.0±1.8)%, (40.9±2.0)%, (17.9±1.1)%, and (5.0±1.0)%, respectively, which were significantly lower than (84.2±1.9)%, (45.4±2.6)%, (21.8±1.7)%, and (10.1±1.1)% in blank control group (

=5.42, 3.09, 4.33, 7.58,

<0.05 or

<0.01) and (82.7±1.2)%, (44.8±2.0)%, (22.4±2.4)%, and (10.3±2.4)% in scaffold alone group (

=4.98, 3.11, 3.84, 4.57,

<0.05 or

<0.01), while the percentages of wound areas of rats between blank control group and scaffold alone group were similar (

=1.47, 0.39, 0.47, 0.22,

>0.05). On PID 21, the layer of new skin at the wound edge of rats in each group was intact; compared with that in blank control group or scaffold alone group, the new skin tissue at the wound edge of rats in ESCs scaffold group had more orderly collagen arrangement; the scaffolds in the new skin at the wound edge of rats were completely degraded in ESCs scaffold group and scaffold alone group. On PID 21, the protein expression levels of Notch1, Jagged1, and Hes1 in the new skin tissue at the wound edge of rats in scaffold alone group were similar to those in blank control group (

=1.70, 1.94, 0.18,

>0.05), while the protein expression levels of Notch1, Jagged1, and Hes1 in the new skin tissue at the wound edge of rats in ESCs scaffold group were significantly higher than those in scaffold alone group (

=13.31, 22.07, 20.71,

<0.01). Conclusions PCL-CA nanofiber scaffolds can inhibit the differentiation of ESCs of rats without affecting their proliferation

. ESCs scaffolds constructed through using PCL-CA nanofiber scaffolds as the carrier to culture ESCs of rats can significantly promote the wound healing of full-thickness skin defects in rats, and the mechanism may be related to the activation of Notch signaling pathway.

Objective To observe the clinical effect of treatment with follicular unit extraction (FUE) and transplantation in treating cicatricial alopecia. Methods The retrospective cohort study was conducted. From January 2012 to January 2018, 56 patients (36 males and 20 females, aged (25±9) years, 1% to 30% alopecia area of the whole scalp area) who met the inclusion criteria visited the outpatient department of the First Affiliated Hospital of Xi'an Medical University. They were treated with FUE transplantation. The procedure of treatment was performed through the preoperative planning, follicular extraction, follicular preparation, punching recipient site and hair transplantation. The survival rate of hair and density of survived hair were calculated, hair growth and complication were observed. The evaluation was conducted through questionnaire survey by 4 levels: very satisfied, satisfied, not satisfied, and not at all satisfied with effects. Results After a follow-up of 9 to 24 months, the survival rate of hair in 56 patients was (70±9)%, and the density of survived hair was (35±8) roots/cm². In the evaluation of the curative effect after the first stage surgery, 34 cases (60.7%) were very satisfied, 16 cases (28.6%) were satisfied, and 6 cases (10.7%)thought the treatment was effective but not satisfied. Six unsatisfactory patients and 16 satisfactory patients underwent the second-stage transplantation, with 19 (86.4%) of them being very satisfied and 3 cases (13.6%) satisfied after the second-stage operation. None of the patients underwent the third-stage surgery. The transplanted hairs grew naturally, and there were no serious complications in all cases. Conclusions FUE transplantation can effectively treat and improve cicatricial alopecia with less trauma, fewer complication, no scar in the donor site and rapid post-operative recovery, so it is worthy of clinical promotion.

Objective To analyze and discuss the psychological needs of family members of critically ill burn inpatients in semi-closed wards and their related influence factors. Methods A cross-sectional survey was conducted among the 82 burn patients, who met the inclusion criteria and were admitted to the Department of Burns and Plastic Surgery of Ruijin Hospital of Shanghai Jiao Tong University School of Medicine from October 2018 to April 2019, and their family members. A general condition questionnaire of 15 indexes was applied to investigate the general data of burn patients and their family members including cause of burn, gender, age, total burn area, burn depth, burn severity, burn site, and type of medical insurance of patients, kinship with the patients, gender, age, experience of accompanying in intensive care isolation wards, occupation, education level, and monthly income of their family members. The Critical Care Family Needs Inventory (CCFNI) was used to assess each item, each factor, and total scores of the family members of patients including 5 factors and 45 items such as support scale (SS), comfort scale (CS), information scale (IS), proximity scale (PS), assurance scale (AS). CCFNI was used to assess the total scores of patients and their family members after classification according to the general data, the data were statistically analyzed with one-way analysis of variance or independent sample

test. Indicators with statistical significance in the above analysis were selected for multiple linear regression analysis to screen the independent influence factors of psychological needs of patients' family members. CCFNI was used to assess each dimension scores of patients and their family members after classification according to the aforementioned selected independent influence factors including age and burn area of patients, gender, educational level, and experience of accompanying in intensive care isolation wards of their family members, and the data were statistically analyzed with one-way analysis of variance or independent sample

test. Results A total of 82 questionnaires were sent out in this study, and 80 were effectively received, with s a recovery rate of 97.6%. In 80 patients, there were 45 males and 35 females; 35 cases (43.75%) were ≤14 years; most of the patients had flame and thermal burns; 33 patients (41.25%), 21 patients (26.25%), and 26 patients (32.50%) had moderate, severe, and extremely severe burns, respectively; and only 3 patients (3.75%) had no health insurance. In 80 family members of patients, 34 (42.50%) were males and 46 (57.50%) were females; 62.50% in the family members of patients were concentrated between 18 and 45 years old; and 12 family members of patients had experience of accompanying in intensive care isolation wards, accounting for 15.00%. The total CCFNI score of the family members was (141±14) points, and the scores of AS, PS, IS, CS, and SS were (3.77±0.23), (3.43±0.37), (3.53±0.34), (2.50±0.59), and (2.69±0.45) points, respectively. The top five items of the psychological needs of family members of patients were concentrated in three factors (AS, PS, and IS), and the item "ensuring that patients receive the best treatment" ranked the first, with a score of (3.99±0.11) points. There were significant differences on the CCFNI total scores of patients with different age, total burns area, and severity of burns and of their family members with different gender, education level, and whether or not experience of accompanying in intensive care isolation unit (

=4.378, 5.481, 5.913,

=4.027, 14.339, 7.265,

<0.05 or

<0.01). Multiple linear regression analysis showed that the patient's age (≤14, 15-45 years) and total burn area (11%-30%, 31%-49%, ≥50% TBSA) and the patient's family members' gender, educational level, experience of accompanying in intensive care isolation unit could affect the psychological needs of family members of patients (

=3.133, 2.260, 2.297, 2.433, 3.015, 2.200, 2.102, 2.463,

<0.05 or

<0.01). There was statistically significant difference in AS score of the patients' family members with different age (

=4.390,

<0.05). There were significant differences in both IS and AS scores of the patients' family members of patients with different burn area (

=5.042, 3.131,

<0.05 or

<0.01). The AS score of the patients' family members with experience of accompanying in intensive care isolation unit was significantly lower than those without (

=-1.040,

<0.05). The SS score of the patients' family members with college education or above was significantly higher than those with high school (technical secondary school) or below (

=0.657,

<0.05). The IS score of the patients' family members with college education or above was significantly lower than those with high school (technical secondary school) or below (

=-1.438,

<0.05). The SS score of male family members of patients was significantly lower than those of female patients (

=4.149,

<0.05). Conclusions The family members of burn patients in semi-closed ward have the most urgent need to ensure the patients receive the best treatment. Patients' age, total burn area, and their family members' gender, education level, experience of accompanying in intensive care isolation unit are the main factors affecting the psychological needs of family members of patients.

Objective To explore the influence of parental compliance on the treatment of hypertrophic scars in burn children. Methods A retrospective cohort study method was used. From June 2014 to June 2019, 49 children with post-burn hypertrophic scars who met the inclusion criteria and visited the outpatient department of the Department of Burns of the First Affiliated Hospital of Anhui Medical University were included in this study. In the follow-up of 9 months, according to the registration form and the results of the compliance questionnaire for parents, the children were divided into good compliance group (34 cases, 21 males and 13 females, aged 2.0 (2.0, 3.5) years) and poor compliance group (15 cases, 6 males and 9 females, aged 3.0 (2.0, 4.0) years). At the first attendance and in the follow-up of 3, 6, and 9 months, the scar scores of children in good compliance group were evaluated by Vancouver Scar Scale (VSS). At the first attendance and in the follow-up of 9 months, the scar scores of children in poor compliance group were evaluated by VSS. At the first attendance and in the follow-up of 9 months, the scar pruritus scores of children in the 2 groups were evaluated by Verbal Rating Score (VRS). Data was statistically analyzed with chi-square test, Wilcoxon rank sum test, Mann-Whitney

test, independent sample

test, and paired sample

test. Results At the first attendance, the color, vascular distribution, softness, and thickness scores, and total score in VSS scoring of scars of children in the two groups were similar (

=0.834, 0.026, 0.837, 0.076, 1.074,

>0.05). In the follow-up of 9 months, the softness and thickness scores, and total score in VSS scoring of scars of children in good compliance group were significantly lower than those in poor compliance group (

=5.518, 4.732, 5.042,

<0.01). Compared with those in the first attendance, the color, vascular distribution, softness, and thickness scores, and total score in VSS scoring of scars of children in good compliance group were significantly decreased in the follow-up of 9 months (

=5.241, 5.273, 5.214, 5.245, 3.451,

<0.01); the color and vascular distribution scores, and total score in VSS scoring of scars of children in poor compliance group were significantly decreased in the follow-up of 9 months (

=3.606, 3.542, 3.448,

<0.01). At the first attendance, the VRS score of scar pruritus of children in good compliance group was 6.00 (5.00, 6.25) points, which was similar to (5.47±1.69) points in poor compliance group (

=0.607,

>0.05). In the follow-up of 9 months, the VRS score of scar pruritus of children in good compliance group was 1.00 (1.00, 1.25) points, which was significantly lower than (3.27±1.71) points in poor compliance group (

=2.606,

<0.01). Compared with those in the first attendance, the VRS score of scar pruritus of children in good compliance group was significantly decreased in the follow-up of 9 months (

=4.002,

<0.01), while there was no obvious change in poor compliance group in the follow-up of 9 months (

=3.550,

>0.05). Conclusions Under the same treatment plan, good parental compliance has a positive effect on the treatment of hypertrophic scars in burn children decreasing the degree of scar hyperplasia and pruritus.

Hypertrophic scars and keloids are common sequelae after wound healing, with a high incidence, which seriously affect the patient's quality of life. However, there is still a lack of effective prevention and treatment methods, mainly because the pathogenesis of scars is not clear. Current research believe that inflammatory response plays a critical role in the process of scar formation, and through the researches on the mechanisms it is hopeful to find new potential therapeutic drug targets for the prevention and treatment of hypertrophic scars and keloids. This article mainly reviews the research progresses on the role and mechanism of inflammatory cytokines and inflammatory cells in the formation of hypertrophic scars and keloids, as well as drugs, microRNAs, and exosomes, etc., for the treatment of hypertrophic scars and keloids by inhibiting inflammatory response.

Skin is an important defense barrier of human body and one of the most vulnerable organs. Wounds are the result of damage to the integrity of skin. Chronic wounds and hypertrophic scar formation are the results of abnormal wound healing, and are also the clinical problems those need to be resolved urgently in the field of wound repair. In recent years, researchers have found that mesenchymal stem cells (MSCs) can promote wound healing, improve wound healing quality, and reduce scar formation. The therapeutic effect of MSCs may be derived from the exosomes derived from them. This paper reviews the research advances of exosomes derived from MSCs in wound healing and prevention and treatment of hypertrophic scars in recent years and looks up to the prospect for the clinical application.