2022 Vol. 38, No. 10

Expert Forum
In situ monitoring and regulation of local reactive oxygen species levels to promote wound repair
Luo Gaoxing, Deng Jun
2022, 38(10): 899-904. doi: 10.3760/cma.j.cn501225-20220720-00299
Abstract:
Local oxidative stress and inflammatory response are the essential procedures in wound repair, which determine the progress, prognosis, and quality of wound repair. Reactive oxygen species is one of the important indexes reflecting oxidative stress and inflammatory response of body, which is considered as a promising target to be regulated in wound inflammation. Recently, with the rapid development of nanomedicine, our research group and other research groups have successfully developed various diagnosis and treatment reagents for reactive oxygen species through interdisciplinary integration, to monitor and regulate reactive oxygen species in wounds in real time, and to finally achieve the goal of improving the speed and quality of wound repair, thus providing a new strategy and direction for the diagnosis and treatment of local inflammatory response in wounds. This article summarizes reactive oxygen species as the regulatory target of local inflammatory response in wounds, in situ monitoring and precise regulation of reactive oxygen species.
Original Articles·Application of Biological Materials in Wound Repair
Application of three-dimensional bioprinting ink containing platelet-rich plasma derived from human umbilical cord blood in the treatment of full-thickness skin defects in nude mice
Song Wei, Li Zhao, Zhu Shijun, Zhang Chao, Yao Bin, Kong Yi, Liang Liting, Enhejirigala, Fu Xiaobing, Huang Sha
2022, 38(10): 905-913. doi: 10.3760/cma.j.cn501225-20220618-00243
Abstract:
  Objective  To investigate the printability and cytocompatibility of sodium alginate-gelatin (AG) bioink containing platelet-rich plasma derived from human umbilical cord blood (HUCB-PRP), named HUCB-PRP-AG bioink, and the effect of the three-dimensionally printed tissue with the bioink on full-thickness skin defect wounds in nude mice.  Methods  The method of experimental research was used. HUCB-PRP-AG bioinks with 2.5%, 5.0%, and 10.0% of HUCB-PRP by volume were prepared and named 1P-AG, 2P-AG, and 4P-AG, respectively. The appearances of AG, 1P-AG, 2P-AG, and 4P-AG at room temperature were observed, and their viscosity and storage/loss modulus were measured by a rotational rheometer. The above four bioinks were used for three-dimensional bioprinting respectively, and the appearances of the printed tissue were observed (the printed tissue was subsequently cross-linked and used). The four kinds of bioprinted tissue were respectively co-cultured with human umbilical vein endothelial cells (HUVECs) in Transwell chambers with HUVEC special medium for 24 h, and the cell proliferation level was detected by cell counting kit 8 (n=3). The four kinds of bioprinted tissue were respectively cultured in Dulbecco's modified eagle medium for 12, 24, and 48 h, which were dried and weighed, and the degradation rate was calculated (n=3). The expression of vascular endothelial growth factor (VEGF) in the culture supernatant of 1P-AG, 2P-AG, or 4P-AG cultured in phosphate buffer solution at 0.5, 24.0, and 48.0 h was detected by enzyme-linked immunosorbent assay (n=5). Sixteen female BALB/c-NU nude mice aged 6-8 weeks were selected to establish a full-thickness skin defect wound model on the back and were divided into conventional control group with wounds being covered with medical hydrocolloid dressing alone, HUCB-PRP group with additional HUCB-PRP dripping to the wounds, AG group additionally covered with AG printed tissue, and 4P-AG group additionally covered with 4P-AG printed tissue, respectively (with 4 nude mice in each group). The wound healing of 3 nude mice in each group was observed on post injury day (PID) 4, 8, and 14, and the wound healing rate was calculated. The wound tissue of the remaining nude mouse in each group was collected on PID 8, the histopathological changes were observed after hematoxylin and eosin staining, and the CD31-positive new blood vessels were observed after immunohistochemical staining. Data were statistically analyzed with analysis of variance for repeated measurement, least significant difference test, and Bonferroni correction.  Results  At room temperature, AG, 1P-AG, 2P-AG, and 4P-AG were semi-transparent liquid, and AG was light yellow, while 1P-AG, 2P-AG, and 4P-AG were light red but the color successively deepened. The viscosity of AG, 1P-AG, 2P-AG, and 4P-AG decreased with the increase of shear rate at the temperature of 10 ℃ and shear rate of 0.1-10.0 s-1; the storage moduli of the four bioinks were greater than the loss moduli at the temperature of 10 ℃ and angular frequency range of 1-100 rad/s. Both the resolution and morphology of the printed tissue of four bioinks were similar. The proliferation levels of HUVECs co-cultured with 1P-AG, 2P-AG, and 4P-AG printed tissue for 24 h were 0.885±0.030, 1.126±0.032, and 1.156±0.045, respectively, which were significantly higher than 0.712±0.019 of HUVECs co-cultured with AG printed tissue (P<0.01). The proliferation levels of HUVECs co-cultured with 2P-AG and 4P-AG printed tissue for 24 h were significantly higher than the level of HUVECs co-cultured with 1P-AG printed tissue (P<0.01). The degradation rates of 1P-AG, 2P-AG, and 4P-AG printed tissue were significantly higher than those of AG printed tissue at 12, 24, and 48 h of culture (P<0.01). The degradation rates of 2P-AG and 4P-AG printed tissue at 24 and 48 h of culture were significantly higher than those of 1P-AG printed tissue (P<0.01). The degradation rate of 4P-AG printed tissue at 12 h of culture was significantly higher than that of 1P-AG printed tissue (P<0.01), and the degradation rates of 4P-AG printed tissue at 24 and 48 h of culture were significantly higher than those of 2P-AG printed tissue (P<0.01). At 0.5, 24.0, and 48.0 h of culture, the expressions of VEGF in the culture supernatant of 2P-AG printed tissue were significantly higher than those of 1P-AG printed tissue (P<0.01), and the expressions of VEGF in the culture supernatant of 1P-AG and 2P-AG printed tissue were significantly lower than those of 4P-AG printed tissue (P<0.01). The wounds of nude mice in conventional control group and HUCB-PRP group were dry and smaller on PID 8 compared with those on PID 4, and the wounds of nude mice in HUCB-PRP group were smaller with no scabs on PID 14 compared with those in conventional control group. The printed tissue on the wound of nude mice in AG and 4P-AG groups was significantly degraded with no obvious exudation being observed on the wounds on PID 4, the wounds were significantly epithelialized and smaller on PID 8, and there was no scab on the wound on PID 14. The wounds of nude mice in 4P-AG group were completely epithelialized on PID 14. Compared with those in conventional control group, the wound healing rate of nude mice in AG group was significantly decreased on PID 4 (P<0.05), and the wound healing rates of nude mice in HUCB-PRP group and 4P-AG group at all time points after injury and in AG group on PID 8 and 14 were significantly increased (P<0.01). Compared with those in HUCB-PRP group, the wound healing rates of nude mice were significantly decreased on PID 4 and 8 in AG group and on PID 4 in 4P-AG group (P<0.01), while the wound healing rates of nude mice were significantly increased on PID 14 in AG group and on PID 8 and 14 in 4P-AG group (P<0.01). The wound healing rate of nude mice in 4P-AG group was significantly higher than that in AG group at all time points after injury (P<0.01). On PID 8, a large number of inflammatory cells infiltration, a small amount of new microvessels, and a small amount of CD31-positive new blood vessels were observed in the wounds of nude mice in conventional control group; a large number of inflammatory cells infiltration, abundant new microvessels, and quite a lot CD31-positive new blood vessels were observed in the wounds of nude mice in HUCB-PRP group; light inflammatory inflammation, a small amount of new microvessels, and a small amount of CD31-positive new blood vessels were observed in the wounds of nude mice in AG group; light inflammatory inflammation, a large number of new microvessels, and a large number of CD31-positive new blood vessels were observed in the wounds of nude mice in 4P-AG group.  Conclusions  HUCB-PRP-AG bioink has good printability and cytocompatibility, and its three-dimensionally printed tissue can promote vascularization of full-thickness skin defect wounds in nude mice and accelerate wound healing.
Effect of P311 microspheres-loaded thermosensitive chitosan hydrogel on the wound healing of full-thickness skin defects in rats
Zhang Qingrong, Chen Changyou, Xu Na, Lyu Dalun, Jia Jiezhi, Li Wenhong, Luo Gaoxing, Yu Yunlong, Zhang Yi
2022, 38(10): 914-922. doi: 10.3760/cma.j.cn501225-20220414-00135
Abstract:
  Objective  To explore the effect of P311 microspheres-loaded thermosensitive chitosan hydrogel on the wound healing of full-thickness skin defects in rats.  Methods  The method of experimental study was adopted. The polyvinyl alcohol/sodium alginate microspheres (simple microspheres), P311 microspheres, and bovine serum albumin labeled with fluorescein isothiocyanate (FITC-BSA) microspheres were prepared by water-in-oil emulsification, and then their morphology was observed under a light microscope/inverted fluorescence microscope. Chitosan solution was prepared, chitosan solution and β-glycerol phosphate disodium hydrate were mixed to prepare simple thermosensitive hydrogels, and thermosensitive hydrogels loaded with simple microspheres or P311 microspheres were prepared by adding corresponding substances in simple thermosensitive hydrogels. The morphological changes of the prepared four liquids in the state of tilt was observed at 37 ℃. After being freeze-dried, the micromorphology of the prepared four liquids was observed under a scanning electron microscope. Eighteen 3-4-week-old male Sprague-Dawley rats were divided into normal group without any treatment, dressing group, chitosan group, hydrogel alone group, simple microspheres-loaded hydrogel group, and P311 microspheres-loaded hydrogel group, which were inflicted with one full-thickness skin defect wound on both sides of the back spine and were dealt correspondingly, with 3 rats in each group. Rats with full-thickness skin defects in the five groups were collected, the wound healing was observed on post injury day (PID) 0 (immediately), 5, 10, and 15, and the wound healing rates on PID 5, 10, and 15 were calculated. The wound and wound margin tissue of rats with full-thickness skin defects in the five groups on PID 15 and normal skin tissue in the same site of rats in normal group were collected, hematoxylin and eosin staining was conducted to observe the histological changes, immunohistochemical staining was performed to observe the expressions of CD31 and vascular endothelial growth factor (VEGF), and Western blotting was conducted to detect the protein expressions of CD31 and VEGF. The number of samples was all three. Data were statistically analyzed with one-way analysis of variance, analysis of variance for repeated measurement, and Bonferroni correction.  Results  Simple microspheres were spherical, with loose and porous surface. The surfaces of P311 microspheres and FITC-BSA microspheres were smooth without pores, and the FITC-BSA microspheres emitted uniform green fluorescence. The diameters of the three microspheres were basically consistent, being 33.1 to 37.7 μm. Compared with chitosan solution and simple thermosensitive hydrogel, the structures of the two microspheres-loaded hydrogels were more stable in the state of tilt at 37 ℃. The two microspheres-loaded hydrogels had denser network structures than those of chitosan solution and simple thermosensitive hydrogel, and in the cross section of which microspheres with a diameter of about 30 μm could be seen. Within PID 15, the wounds of rats in the five groups were healed to different degrees, and the wound healing of rats in P311 microspheres-loaded hydrogel group was the best. On PID 5, 10, and 15, the wound healing rates of rats in dressing group and chitosan group were (26.6±2.4)%, (38.5±3.1)%, (50.9±1.5)%, (47.6±2.0)%, (58.5±3.6)%, and (66.7±4.1)%, respectively, which were significantly lower than (59.3±4.8)%, (87.6±3.2)%, (97.2±1.0)% in P311 microspheres-loaded hydrogel group (P<0.05 or P<0.01). The wound healing rates of rats in hydrogel alone group on PID 10 and 15, and in simple microspheres-loaded hydrogel group on PID 15 were (76.0±3.3)%, (84.5±3.6)%, and (88.0±2.6)%, respectively, which were significantly lower than those in P311 microspheres-loaded hydrogel group (P<0.05). The epidermis, hair follicles, and sebaceous glands could be seen in the normal skin of rats in normal group, without positive expressions of CD31 or VEGF. The wounds of rats in P311 microspheres-loaded hydrogel group on PID 15 were almost completely epithelialized, with more blood vessels, hair follicles, sebaceous glands, and positive expressions of CD31 and VEGF in the wounds than those of rats with full-thickness skin defects in the other four groups, and more protein expressions of CD31 and VEGF than those of rats in the other five groups.  Conclusions  The P311 microspheres-loaded thermosensitive chitosan hydrogel can release the encapsulated drug slowly, prolong the drug action time, and promote wound healing in rats with full-thickness skin defects by promoting wound angiogenesis and re-epithelialization.
Effects and mechanism of water-soluble chitosan hydrogel on infected full-thickness skin defect wounds in diabetic mice
Zhu Meng, Chen Yuzhou, Ou Jinzhao, Li Zhao, Huang Sha, Hu Xiaohua, Ju Xiaoyan, Tian Ye, Niu Zhongwei
2022, 38(10): 923-931. doi: 10.3760/cma.j.cn501225-20220507-00175
Abstract:
  Objective  To explore the effects and mechanism of water-soluble chitosan hydrogel on infected full-thickness skin defect wounds in diabetic mice.  Methods  The experimental research method was adopted. The control hydrogel composed of polyvinyl alcohol and gelatin, and the water-soluble chitosan hydrogel composed of the aforementioned two materials and water-soluble chitosan were prepared by the cyclic freeze-thaw method. The fluidity of the two dressings in test tube before and after the first freeze-thawing was generally observed, and the difference in appearance of the final state of two dressings in 12-well plates were compared. According to random number table (the same grouping method below), the cell strains of L929 and HaCaT were both divided into water-soluble chitosan hydrogel group and control hydrogel group, respectively. After adding corresponding dressings and culturing for 24 h, the cell proliferation activity was measured using cell counting kit 8. Rabbit blood erythrocyte suspensions were divided into normal saline group, polyethylene glycol octyl phenyl ether (Triton X-100) group, water-soluble chitosan hydrogel group, and control hydrogel group, which were treated accordingly and incubated for 1 hour, and then the hemolysis degree of erythrocyte was detected by a microplate reader. Twenty-four female db/db mice aged 11-14 weeks were selected, and full-thickness skin defect wounds on their backs were inflicted and inoculated with the methicillin-resistant Staphylococcus aureus (MRSA), 72 h later, the mice were divided into blank control group, sulfadiazine silver hydrogel group, control hydrogel group, and water-soluble chitosan hydrogel group, which were treated accordingly. On post injury day (PID) 0 (immediately), 7, 14, and 21, the healing of the wound was observed. On PID 14 and 21, the wound healing rate was calculated. On PID 14, MRSA concentration in wounds was determined. On PID 21, the wounds were histologically analyzed by hematoxylin and eosin staining; the expression of CD31 in the wounds was detected by immunofluorescence method, and its positive percentage was calculated. Raw264.7 cells were taken and divided into interleukin-4 (IL-4) group, blank control group, control hydrogel group, and water-soluble chitosan hydrogel group, which were treated accordingly. At 48 h of culture, the percentages of CD206 positive cells were detected by flow cytometry. The number of samples was all 3. Data were statistically analyzed with independent sample t test, one-way analysis of variance, analysis of variance for repeated measurement, least significant difference test, and Dunnett T3 test.  Results  Two dressings in test tube had certain fluidity before freeze-thawing and formed semi-solid gels after freeze-thawing for once. The final forms of two dressings in 12-well plates were basically stable and translucent sheets, with little difference in transparency. At 24 h of culture, the cell proliferation activities of L929 and HaCaT in water-soluble chitosan hydrogel group were significantly higher than those in control hydrogel group (with t values of 6.37 and 7.50, respectively, P<0.01). At 1 h of incubation, the hemolysis degree of erythrocyte in water-soluble chitosan hydrogel group was significantly lower than that in Triton X-100 group (P<0.01), but similar to that in normal saline group and control hydrogel group (P>0.05). On PID 0, the traumatic conditions of mice in the 4 groups were similar. On PID 7, more yellowish exudates were observed inside the wound in blank control group and control hydrogel group, while a small amount of exudates were observed in the wound in sulfadiazine silver hydrogel group and water-soluble chitosan hydrogel group. On PID 14, the wounds in blank control group and control hydrogel group were dry and crusted without obvious epithelial coverage; in sulfadiazine silver hydrogel group, the scabs fell off and purulent exudate was visible on the wound; in water-soluble chitosan hydrogel group, the base of wound was light red and obvious epithelial coverage could be observed on the wound. On PID 14, the wound healing rate in water-soluble chitosan hydrogel group was significantly higher than that in the other 3 groups (all P<0.01). On PID 21, the wound in water-soluble chitosan hydrogel group was completely closed, while the wounds in the other 3 groups were not completely healed; the wound healing rate in water-soluble chitosan hydrogel group was significantly higher than that in the other 3 groups (all P<0.01). On PID 14, the concentration of MRSA in the wound in water-soluble chitosan hydrogel group was significantly lower than that in blank control group (P<0.01), but similar to that in control hydrogel group and sulfadiazine silver hydrogel group (P>0.05). On PID 21, the new epidermis was severely damaged in blank control group; the epidermis on the wound in control hydrogel group also had a large area of defect; complete new epidermis had not yet being formed on the wound in sulfadiazine silver hydrogel group; the wound in water-soluble chitosan hydrogel group was not only completely covered by the new epidermis, the basal cells of the new epidermis were also regularly aligned. On PID 21, the percentage of CD31 positivity in the wound in water-soluble chitosan hydrogel group was (2.19±0.35)%, which was significantly higher than (0.18±0.05)% in blank control group, (0.23±0.06)% in control hydrogel group, and (0.62±0.25)% in sulfadiazine silver hydrogel group, all P<0.01. At 48 h of culture, the percentage of CD206 positive Raw264.7 cells in water-soluble chitosan hydrogel group was lower than that in IL-4 group (P>0.01) but significantly higher than that in blank control group and control hydrogel group (P<0.05 or P<0.01).  Conclusions  The water-soluble chitosan hydrogel has good biosafety and can induce higher level of macrophage M2 polarization than control hydrogel without water-soluble chitosan, so it can enhance the repair effect of MRSA-infected full-thickness skin defect wounds in diabetic mice and promote rapid wound healing.
Original Articles
Clinical effects of lateral supramalleolar perforator island flaps with low rotation points in repairing foot skin and soft tissue defect wounds
Chen Liming, Wang Gang, Liu Yi
2022, 38(10): 932-936. doi: 10.3760/cma.j.cn501120-20210630-00231
Abstract:
  Objective  To investigate the clinical effects of lateral supramalleolar perforator island flaps with low rotation points in repairing foot skin and soft tissue defect wounds.  Methods  The retrospective observational study was conducted. From October 2017 to August 2020, 14 patients (6 males and 8 females, aged 14-77 years) with foot skin and soft tissue defect wounds were admitted to Lanzhou University Second Hospital, including 4 cases of plantar skin tumor, 4 cases of chronic plantar ulcer, 4 cases of foot traffic injury, and 2 cases of residual wounds after deep foot burns. The wound size was 2.0 cm×2.0 cm to 7.0 cm×5.0 cm after tumor resection or debridement, which was repaired with island flap pedicled with the descending branch of the lateral supramalleolar perforator and the rotation point located at the lower front edge of the lateral ankle. The size of the flap ranged from 3.0 cm×2.0 cm to 8.0 cm×6.0 cm, and the length of vascular pedicle ranged from 8.0 to 14.0 cm. The flap was transferred by subcutaneous tunnel to repair the wound. The donor site wound of the flap was repaired with medium thickness skin graft from the lateral thigh. The survival of flaps, wound healing of the donor and recipient sites, and the occurrence of complications after operation were observed. The appearances of flaps and donor sites, and foot function were observed during follow-up.  Results  The flaps of 14 patients survived successfully after operation, and the wounds in the donor and recipient sites healed well, without vascular crisis, venous congestion, or other complications. Follow-up for 2 to 24 months showed that the flaps had good appearance without bloating and were wear-resistant, the functions of wearing shoes and walking were not affected, and there was no obvious scar hyperplasia or hyperpigmentation at the donor site.  Conclusions  With the descending branch of the lateral supramalleolar perforator as the pedicle and the rotation point located at the lower front edge of the lateral ankle, the island flap has a good effect in repairing the skin and soft tissue defect wound of the foot because of its reliable blood supply, simple design and operation, no need for vascular anastomosis, low rotation point, long vascular pedicle, and large radius of rotation.
Comparative study of the effects between second toe tibial dorsal artery flap and second toe tibial plantar proper artery flap in repairing finger skin and soft tissue defects
Li Jin, Wu Haibo, Jin Guangzhe, Zhu Congkun, Wang Kai, Wang Qiang, Ju Jihui, Hou Ruixing
2022, 38(10): 937-943. doi: 10.3760/cma.j.cn501120-20210909-00310
Abstract:
  Objective  To compare the effects between second toe tibial dorsal artery flap (2-TDAF) and second toe tibial plantar proper artery flap (2-TPPAF) in repairing finger skin and soft tissue defects.  Methods  A retrospective cohort study was conducted. From January 2019 to June 2020, 27 patients with skin and soft tissue defects at the fingertips with area of 1.5 cm×1.2 cm-2.6 cm×1.8 cm after debridement who met the inclusion criteria were admitted to Suzhou Ruihua Orthopaedic Hospital, including 21 males and 6 females, aged 19-59 (37±10) years. According to flap repair methods used in the defective fingers, the patients were divided into 2-TDAF group (12 cases) and 2-TPPAF group (15 cases). The area of 2-TDAF ranged from 1.5 cm×1.2 cm to 2.5 cm×1.6 cm, and the area of 2-TPPAF ranged from 1.7 cm×1.3 cm to 2.6 cm×1.8 cm. Full-thickness skin grafts from the medial side of the ipsilateral leg were grafted to the wounds in donor sites, and the wounds in donor sites of skin grafts were directly sutured. Flap arterial diameter, flap excision time, flap survival situation of patients in 2 weeks after operation, and follow-up time were recorded. At the last follow-up, the two-point discrimination distance of flap graft site, total action motion (TAM) of the finger joints, and wound healing of the flap donor site were recorded; the Vancouver scar scale (VSS) was used to score the scar in donor area of the second toe and the recipient area of fingers; the appearance and self-satisfaction subscales of the Michigan hand outcomes questionnaire (MHQ) were used to evaluate the affected finger. Data were statistically analyzed with independent sample t test or Fisher's exact probability test.  Results  The flap artery diameter of patients in 2-TDAF group was 0.35-0.80 (0.56±0.14) mm and the flap cutting time was (14.0±2.7) min, which were significantly shorter than 0.80-1.35 (1.02±0.16) mm and (19.7±3.4) min in 2-TPPAF group (with t values of 7.81 and 4.79, respectively, P<0.01). The flaps of patients in the 2 groups in recipient areas survived well in 2 weeks after operation, and the wounds in donor areas of flaps of patients in the 2 groups healed well at the last follow-up. There was no statistically significant difference in the postoperative follow-up time, and two-point discrimination distance of flap graft site, TAM of the finger joints, VSS score of scar in the second toe donor site and the finger recipient site, and the appearance and self-satisfaction of MHQ scores of the affected finger at the last follow-up (P>0.05).  Conclusions  Compared with 2-TPPAF, 2-TDAF has a shallower anatomical layer and shorter time for surgical flap removal, which can preserve the proper arteries and nerves at the base of the toes and reduce the damage to the donor site.
Screening, functional analysis and clinical validation of differentially expressed genes in diabetic foot ulcers
Wang Peng, Chen Zhaohong, Jiang Liyuan, Zhou Xiaoqian, Jia Chiyu, Xiao Hou'an
2022, 38(10): 944-951. doi: 10.3760/cma.j.cn501225-20220731-00328
Abstract:
  Objective  To screen the differentially expressed genes (DEGs) in diabetic foot ulcers (DFUs), and to perform functional analysis and clinical validation of them, intending to lay a theoretical foundation for epigenetic therapy of chronic refractory wounds.  Methods  An observational study was conducted. The gene expression profile dataset GSE80178 of DFU patients in Gene Expression Omnibus (GEO) was selected, and the DEG between three normal skin tissue samples and six DFU tissue samples in the dataset was analyzed and screened using the GEO2R tool. For the screened DEG, ClusterProfiler, org.Hs.eg.db, GOplot, and ggplot2 in the R language packages were used for Gene Ontology (GO) enrichment analysis of biological processes, molecular functions, and cellular components, and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, respectively. Protein-protein interaction (PPI) analysis was performed using STRING database to screen key genes in the DEG, and GO enrichment analysis of key genes was performed using Cytohubba plug-in in Cytoscape 3.9.1 software. DFU tissue and normal skin tissue discarded after surgery were collected respectively from 15 DFU patients (7 males and 8 females, aged 55-87 years) and 15 acute wound patients (6 males and 9 females, aged 8-52 years) who were admitted to Xiang'an Hospital of Xiamen University from September 2018 to March 2021. The mRNA and protein expressions of small proline-rich repeat protein 1A (SPRR1A) and late cornified envelope protein 3C (LCE3C) were detected by real-time fluorescent quantitative reverse transcription polymerase chain reaction and immunohistochemistry, respectively. Data were statistically analyzed with independent sample t test.  Results  Compared with normal skin tissue, 492 statistically differentially expressed DEGs were screened from DFU tissue of DFU patients (corrected P<0.05 or corrected P<0.01), including 363 up-regulated DEGs and 129 down-regulated DEGs. GO terminology analysis showed that DEGs were significantly enriched in the aspects of skin development, keratinocyte (KC) differentiation, keratinization, epidermal development, and epidermal cell differentiation, etc. (corrected P values all <0.01). KEGG pathway analysis showed that DEGs were significantly enriched in the aspects of tumor-associated microRNA, Ras related protein 1 signaling pathway, and pluripotent stem cell regulatory signaling pathway, etc. (corrected P values all <0.01). PPI analysis showed that endophial protein, SPRR1A, SPRR1B, SPRR2B, SPRR2E, SPRR2F, LCE3C, LCE3E, keratin 16 (all down-regulated DEGs), and filoprotein (up-regulated DEG) were key genes of DEGs screened from DFU tissue of DFU patients, which were significantly enriched in GO terms of keratinization, KC differentiation, epidermal cell differentiation, skin development, epidermis development, and peptide cross-linking, etc. (corrected P values all <0.01). The mRNA expressions of SPRR1A and LCE3C in DFU tissue of DFU patients were 0.588±0.082 and 0.659±0.098, respectively, and the protein expressions were 0.22±0.05 and 0.24±0.04, respectively, which were significantly lower than 1.069±0.025 and 1.053±0.044 (with t values of 20.91 and 13.66, respectively, P values all <0.01) and 0.38±0.04 and 0.45±0.05 (with t values of 9.69 and 12.46, respectively, P values all <0.01) in normal skin tissue of acute wound patients.  Conclusions  Compared with normal skin tissue, there is DEG profile in DFU tissue of DFU patients, with DEGs being significantly enriched in the aspects of KC differentiation and keratin function. Key DEGs are related to the biological function of KC, and their low expressions in DFU tissue of DFU patients may impede ulcer healing.
Original Article·Nursing Column
Clinical application effect of sequential nursing on the management of new skin on face and neck after deep burns
Fu Qingqing, Li Maojun, Huang Ling, Tan Jianglin, Zhou Yaqin, Li Ning
2022, 38(10): 952-958. doi: 10.3760/cma.j.cn501120-20210323-00101
Abstract:
  Objective  To explore the clinical application effect of sequential nursing on the management of new skin on face and neck after deep burns.  Methods  The retrospective case-control research approach was used. From January to December 2019, 109 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Army Medical University (the Third Military Medical University) within 1 week after deep burn wound healing on the face and neck. Fifty-five patients who were admitted to the hospital from January to June and received comprehensive treatment and conventional nursing were included in conventional nursing group (27 males and 28 females, aged 21-65 (40±17) years), and fifty-four patients who were admitted to the hospital from July to December and received comprehensive treatment and sequential nursing were included in sequential nursing group (29 males and 25 females, aged 18-57 (37±11) years). The scores of pigmentation, vascularity, pliability, and thickness in Vancouver scar scale (VSS), the total score of VSS, the score of itch's impact on sleep in the four-item itch questionnaire (FIIQ), and the total score of FIIQ of patients were counted in the two groups before the first treatment (hereinafter referred to as treatment) and 3 months, 6 months, and 1 year after treatment. The treatment effective rate and the score of patients' satisfaction with the treatment effect in one year after treatment and the occurrence of adverse reaction during the treatment were counted. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, and chi-square test.  Results  The scores of pigmentation, vascularity, pliability, and thickness in VSS and the total VSS score of patients between the two groups before treatment were close (P>0.05). The pliability score in VSS and total VSS score after 3 months of treatment, the score of vascularity in VSS and total VSS score after 6 months of treatment, and the scores of pigmentation, vascularity, pliability, and thickness in VSS and total VSS score of patients after 1 year of treatment in sequential nursing group were significantly lower than those in conventional nursing group (with Z values of -2.51, -3.37, -2.05, -3.28, -3.12, -5.86, -4.63, -5.56, -6.76, respectively, P<0.05 or P<0.01). The score of itch's impact on sleep in FIIQ after 3 months of treatment of patients in sequential nursing group was significantly lower than that in conventional nursing group (Z=-4.17, P<0.01), and the total scores of FIIQ after 3 months, 6 months, and 1 year of treatment of patients in sequential nursing group were significantly lower than those in conventional nursing group (with Z values of -6.56, -5.53, -5.84, respectively, P<0.01). After 1 year of treatment, the treatment effective rate of patients in sequential nursing group was 96.3% (52/54), which was significantly higher than 81.8% (45/55) in conventional nursing group (χ2=5.83, P<0.05), and the score of patients' satisfaction with the treatment effect in sequential nursing group was significantly higher than that in conventional nursing group (Z=-4.49, P<0.01). During the treatment period, there was no adverse reaction in patients in sequential nursing group, but there were 3 patients with pruritus and peripheral erythema on the wound in conventional nursing group, which were improved after dressing changes.  Conclusions  Sequential nursing can effectively improve the prevention and management of new skin scars in patients after deep burns on the face and neck, improve the itching, the efficiency of treatment, and the satisfaction of patients with the treatment effect.
Wound Repair
Clinical effects of proximal ulnar artery perforator flap combined with iliac bone graft in the reconstruction of subtotal thumb or finger defects
Zhang Yujun, Ju Jihui, Zhao Qiang, Wang Benyuan, Cheng Heyun, Wang Guiyang, Hou Ruixing
2022, 38(10): 959-963. doi: 10.3760/cma.j.cn501120-20210707-00238
Abstract:
  Objective  To explore the clinical effects of proximal ulnar artery perforator flap combined with iliac bone graft in the reconstruction of subtotal thumb or finger defects.  Methods  A retrospective observational study was conducted. From August 2016 to August 2019, 7 patients with thumb or finger defects caused by mechanical damage who met the inclusion criteria were admitted to Ruihua Affiliated Hospital of Soochow University, including 6 males and 1 female, aged 46 to 58 years. Their length of fingers was repaired with iliac bone, with length of 2.0 to 3.0 cm. After the bone graft, the skin defect area of the affected finger ranged from 2.8 cm×2.2 cm to 6.0 cm×3.2 cm. Then the free proximal ulnar artery perforator flap with area of 3.0 cm×2.4 cm to 6.5 cm×3.5 cm was used to cover the wounds. The wounds in donor sites of iliac crest and flap were directly sutured. The survival of flap in one week post surgery and the donor site wound healing in 2 weeks post surgery were observed, respectively. During the follow-up, the appearance and sensory function of the affected finger, bone healing, and scar hypertrophy of wound in the donor site were observed and evaluated. At the last follow-up, the functional recovery of the affected finger was evaluated with trial standard for the evaluation of functions of the upper limbs of the Hand Surgery Society of Chinese Medical Association.  Results  In one week post surgery, all the flaps survived. In 2 weeks post surgery, the iliac bone and the wounds in forearm donor site healed. During the follow-up of 5 to 13 months, the flap was good in appearance, without obvious pigmentation; the sensory recovery reached level S2 in 5 patients and S0 in 2 patients; all the grafted iliac bones were bony union without obvious resorption; the wounds in donor site healed well, with only mild scar formation. At the last follow-up, the shape of the reconstructed finger was close to the healthy finger, and the functional evaluation results were excellent in 3 cases and good in 4 cases.  Conclusions  The use of proximal ulnar artery perforator flap combined with iliac bone graft to reconstruct subtotal thumb or finger can partially restore part of the appearance and function, with less damage to the donor site. It is a good choice for patients who have low expectations of appearance and function for the reconstructed finger.
Case Report and Literature Review
Transplantation of bilateral superficial inferior epigastric artery perforator flap for breast reconstruction in a patient with unilateral breast cancer
Song Dajiang, Li Zan, Zhou Xiao, Zhang Yixin, Zhou Bo, Lyu Chunliu, Tang Yuanyuan, Yi Liang, Luo Zhenhua
2022, 38(10): 964-967. doi: 10.3760/cma.j.cn501225-20220306-00047
Abstract:
On May 14, 2020, a 37 year old female patient with unilateral breast cancer was admitted to Hunan Cancer Hospital. She underwent modified radical mastectomy for right breast cancer and free transplantation of bilateral superficial inferior epigastric artery perforator flap (weighed 305 g) for breast reconstruction. During the operation, the right inferior epigastric vascular pedicle was anastomosed with the proximal end of the right internal mammary vessel, and the left inferior epigastric vascular pedicle was anastomosed with the distal end of the right internal mammary vessel; the blood flow of the flap was good; the wound in the donor site of the abdominal flap was closed directly. The operation lasted for 9 hours. In the first 48 hours post operation, the flap showed mild elevation in perfusion over drainage, but no obvious edema or blister was observed, flap temperature was consistent with the surrounding skin, and the drainage volume out of drainage tube was only 40 mL. The blood supply of the flap was completely restored to normal 3 days post operation, the flap survived well, the donor site incision had no obvious tension, and the healing was smooth. After 2 months of follow-up, the donor site incision of abdomen healed completely, only linear scar was left, and the reconstructed breast had a natural appearance; the patient planned to perform further nipple reconstruction and contralateral breast mastopexy. This case suggests that autologous breast reconstruction can be performed using bilateral superficial inferior epigastric artery perforator flaps under certain circumstances to minimize donor site injury to the greatest extent.
Reviews·Application of Biological Materials in Wound Repair
Research advances on the construction of artificial dermal scaffolds based on biomaterials
Chen Jiqiu, Zhu Shihui
2022, 38(10): 968-972. doi: 10.3760/cma.j.cn501225-20220606-00221
Abstract:
In the field of wound repair, scarless healing and complete reconstruction of skin function are major challenges in clinical and basic research. At present, a variety of artificial dermal scaffolds have been used in the clinical repair of wounds to overcome the problems such as skin structural disorders caused by tissue defects. The biomaterials used to make artificial dermal scaffolds in skin and tissue engineering research mainly include three categories: natural biomaterials, biosynthetic materials, and organic polymer materials. This review summarizes the biocompatibility, bioactivity, and degradability of biomaterials and their effects on wound healing, and provides an overview of artificial dermal scaffold construction strategies based on biomaterials, wound healing cells, and associated cytokines.
Research advances on the application of silk fibroin biomaterials in wound repair
Ding Zhaozhao, Lyu Qiang
2022, 38(10): 973-977. doi: 10.3760/cma.j.cn501225-20220602-00212
Abstract:
Silk fibroin, a natural fibrin, is a suitable matrix biomaterial for wound repair due to its unique properties such as good biocompatibility, tunable biodegradation and mechanical properties, low host inflammatory response, low cost, ease of fabrication, etc. Silk fibroin can be used alone or in combination with other materials to construct various dressings including scaffolds, hydrogels, films, smart mats, and microneedles, which can meet the needs of different wound repair and regulate the wound repair process. Thus, the application research of silk fibroin in skin tissue engineering has increased dramatically. Compared with other natural materials, silk fibroin promotes tissue regeneration and wound repair by improving cell proliferation, migration, and differentiation behavior at different stages, showing unique advantages in different dimensions. Based on the development of silk fibroin wound repair materials in the recent years, this review focuses on the mechanism and application prospect of silk fibroin and its composite materials in wound repair.
Research advances on the application of natural and recombinant collagen in wound repair
Liu Xiaogang, Chen Lei, Li Haihang, Hu Yanke, Xiong Yahui, Huang Wei, Su Shasha, Qi Shaohai
2022, 38(10): 978-982. doi: 10.3760/cma.j.cn501120-20211123-00394
Abstract:
Collagen is a macromolecular protein constituting the extracellular matrix of animal connective tissue, which has been widely used and developed in fields of biomedicine, tissue engineering, food, and cosmetics. Due to its advantages such as abundant sources and good biocompatibility, low immunogenicity, and degradability, collagen can be used as a dressing or tissue engineering scaffold for wound repair. According to the source of materials, collagen can be divided into natural collagen and recombinant collagen. Natural collagen is mainly extracted directly from mammals and fish; recombinant collagen is obtained based on genetic engineering technology, and its sources include recombinant expression systems of microorganisms, animals, and plants. This paper summarizes the sources of collagen, and the roles, advantages, and disadvantages of different sources of collagen in wound repair, the particularity and superiority of collagen combined with three-dimensional printing technology in wound repair, the impact of market norms of China's collagen industry on the field of wound repair, and explains the precautions for the development of collagen-related products, aiming to provide new ideas for selecting a suitable source of collagen for wound repair.
Reviews
Research advances on the construction of an ideal scar model in vitro based on innovative tissue engineering technology
Zhu Dongzhen, Yao Bin, Yan Ziqiang, Huang Sha, Fu Xiaobing
2022, 38(10): 983-988. doi: 10.3760/cma.j.cn501120-20210723-00257
Abstract:
The scar brings a huge economic burden and creates a serious psychological shadow for patients. Although the current methods for scar treatment tend to be diversified, the treatment method that can truly achieve the goal of "perfect healing" or "scarless healing" after human skin injury is quite scarce. With the wide application of tissue engineering technologies in medicine research, technologies such as three-dimensional bioprinting, organoid culture, and organ chip technologies are constantly emerging. Disease models in vitro based on these innovative technologies showed more advantages than traditional animal disease models. The article introduces the current hotspot technologies in skin tissue engineering such as organoid culture, three-dimensional bioprinting, and organ chip technologies, focuses on summarizing the three key elements to be mastered for constructing an ideal scar model in vitro, and puts forward the future prospect of constructing an ideal scar model in vitro based on our research team's long-term experience in skin tissue repair and regeneration research.
Research advances on the effects of RNA N6-methyladenosine modification in the relevant pathophysiological processes of wound repair
Liu Xiaoxiao, Liu Dewu
2022, 38(10): 989-993. doi: 10.3760/cma.j.cn501120-20210804-00267
Abstract:
N6-methyladenosine (m6A) exists widely in eukaryotes as a post-transcriptional modification. This modification is dynamically and reversibly regulated by methyltransferases and demethylases, and is involved in regulating biological effects through m6A binding proteins. Recent studies have elucidated that m6A is involved in embryonic skin morphogenesis, wound repair, and pathophysiological processes such as inflammatory response, angiogenesis, and fibrosis. This review summarizes the role of m6A and its related proteins in the related pathophysiological processes of wound repair, so as to provide a new theoretical basis for the treatment strategy of wound repair.
Research advances on burn blister fluid
Dong Hongfei, Huang Xi, You Shuang, Li Xianhui
2022, 38(10): 994-998. doi: 10.3760/cma.j.cn501120-20211109-00380
Abstract:
Burns often cause the damaged tissue to produce a large amount of exudate and the formation of blisters on the wound. The burn blister fluid contains a large number of molecules related to wound healing, which can reflect the state of local tissue microenvironment of the burn wound. Analyzing relevant information such as cellular components, signal mediators, and protein molecules in burn blister fluid is helpful to understand the local reaction and tissue microenvironment of burn wounds, and then help clinical burn treatment. In this article, by understanding the production mechanism of burn blister fluid, discussing its role in wound evaluation, and integrating the research progress of burn blister fluid in proteomics, metabolomics, cellular components, and pharmacokinetics, we propose our thoughts and prospects on the research of burn blister fluid, in order to provide assistance for clinical evaluation and treatment of burn wounds, and also provide idea for the follow-up study of burn blister fluid.