Global burden of burns and its association with socio-economic development status, 1990-2019.

BACKGROUND: Burns represent important global health problems. Whereas many studies are limited by the difficulties in estimating the burden of burns and instead focus on the causes of burns, such as fire, heat, and hot substances. Therefore, a complete assessment of the burden of all injuries leading to burns is essential to developing reasonable global intervention strategies. METHODS: Data on three classes of burns, including "< 20 % total burned surface area without lower airway burns" (Moderate injury), "> =20 % total burned surface area or > = 10 % burned surface area if head/neck or hands/wrist involved w/o lower airway burns" (Major injury), "Lower airway burns" (Inhalation injury) were collected from the Global Burden of Disease 2019 database. Age-standardized incidence rates (ASR-I) and Years Lived with Disability (ASR-YLDs) for burns has been standardized by removing the influence of population size and age structure. They were extracted and stratified by cause, year, sex, age, socio-demographic index, country, and territory. RESULTS: In terms of ASR-I and ASR-YLDs, burns showed a significant decrease from 1990 to 2019, especially for moderate and major injury. In 2019, the burden of moderate injury was positively correlated with socio-demographic index while major injury was negatively correlated (P < 0.05). We found no correlation between socio-demographic index and the burden for inhalation injury (P > 0.05). Fire, heat, and hot substances were the most important cause of burns except for inhalation injury. The most common association with inhalation injury was falls, which were also a major cause of moderate and major injury. CONCLUSIONS: The Global Burden of Disease 2019 database data can be used to guide the allocation of resources to reduce ASR-I and ASR-YLDs of different burn classes.

Transcriptomic analysis of mRNA expression in giant congenital melanocytic nevi.

BACKGROUND AND OBJECTIVE: GCMN is a sporadic disease with an incidence ranging from 1/20,000 to 1/500000. So far, several studies have found that GCMN is related to somatic mutations, but most of them have focused on known pathogenic genes, and transcriptome sequencing based on large datasets is relatively uncommon. At present, the use of next-generation sequencing technologies and bioinformatics platforms makes genomic information study more comprehensive and efficient. In this study, the transcriptome differences between GCMN lesions and surrounding normal skin tissues were investigated using high-throughput transcriptome sequencing, and hub genes and pathways related to pathogenesis were identified, providing a theoretical foundation for further research into the pathogenesis of GCMN. METHODS: Pathological skin tissue and surrounding normal skin tissue from GCMN patients, namely the pathological group (PG) and the control group (CG), were obtained. 1. All specimens were stained with HE to ensure that the samples met the experimental requirements. 2. Ten pairs of specimens were selected for high-throughput transcriptome sequencing, and the differentially expressed genes (DEGs) between the PG and the CG were obtained. The DEGs were analyzed by clusterProfiler R software for Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. The function of the subnetwork was analyzed and the hub genes were identified by the STRING database and Cytoscape software. 3. The expression differences of hub genes PTGS2, EGF, and SOX10 in pathological skin tissues and normal skin tissues were verified by qRT-PCR and immunofluorescence staining. RESULTS: 1. HE staining revealed a lot of melanocytes in the dermis and subcutaneous tissues. They were found around the hair follicles, sweat glands, sebaceous glands, and blood vessel walls, or in a specific pattern. 2. The screening threshold was set at p < 0.01 and |log2fc|<1, and a total of 1163 DEGs were discovered between the PG and CG, with 519 genes up-regulated and 644 genes down-regulated in the pathological tissues. According to the GO functional analysis, 29 biological processes, 18 cell compositions, and 17 molecular functions were significantly enriched, with the majority of them being related to keratinocytes and the extracellular matrix. There were 779 nodes and 2359 interactions in the protein interaction network. Using the MCODE plug-in, the network was divided into 25 functional clusters. According to ClueGO results, Cluster5 was involved in melanin biosynthesis and melanocyte proliferation. Using 11 operation methods in the Cytohubba plug-in, PTGS2, EGF, and SOX10 in Cluster5 were chosen as hub genes. 3. qRT-PCR and immunofluorescent staining revealed that compared to normal skin tissue, the expression of SOX10 was significantly up-regulated, and the expression of PTGS2 and EGF was significantly down-regulated in pathological skin tissue(P < 0.001). CONCLUSIONS: In GCMN, keratinocytes and extracellular matrix may directly and indirectly affect melanocyte activity. PTGS2, EGF, and SOX10 are important genes and significantly differentially expressed in pathological and normal skin tissues. These findings may serve as a springboard for future research.

An improved explants culture method: Sustainable isolation of keloid fibroblasts with primary characteristics.

BACKGROUND: Keloid (KD) is a complex fibroproliferative disease, but the exact mechanisms underlying keloid pathogenesis remain to be elucidated. The primary keloid fibroblasts (KFs) culture in vitro has always been a fundamental measure to study the pathogenesis of keloid. However, the traditional primary culture methods have some limitations, such as a long culture cycle, low specimen utilization rate and so on. AIMS: Improve the keloid explants culture method sts. MATERIALS & METHODS: We proposed an improved new "explants multiple culture method"-reusing keloid explants for primary culture and harvesting the primary KFs in specific culture times. Meanwhile, the purity, proliferation, apoptosis, migration, invasion, extracellular matrix synthesis, and some fibrosis and inflammation-related proteins of KFs obtained from the first, fifth, and tenth explants cultures were detected. RESULTS: The results showed that the culture cycle of this new method (Cell Isolation: 2.67 ± 0.86 days, Explants removal: 8.83 ± 0.79 days, Cell Passage: 15.17 ± 1.39 days) was significantly shorter than that of the traditional method (Cell Isolation: 8.67 ± 1.84 days, Explants removal: 17.67 ± 2.17 days, Cell Passage: 22.67 ± 1.84 days). No significant difference was observed between the phenotypes of the fibroblasts obtained from the first explants culture and cultures less than 10 times (p > 0.05). DISSCUSSION: Taken together, this study provides an effective method for the primary culture of KFs with a higher specimen utilization rate and shorter culture cycle. CONCLUSION: This method breaks through the limitation of traditional explants culture requiring a large number of keloid specimens and provides a rich source of KFs for the study of keloid.

Comparison of three different surgical approaches for the treatment of large/giant congenital melanocytic nevus.

OBJECTIVE: Treating large/giant congenital melanocytic nevus (L/GCMN) is challenging for surgeons. Operative approaches commonly used to remove L/GCMN include serial excision, tissue expansion, and skin grafting. Thus, we retrospectively compared these three operations' applications and therapeutic effects. METHODS: The clinical data of 97 L/GCMN patients from June 1, 2015, to June 1, 2019, were collected and divided into three groups according to the operations used: serial excision group (SE group, n = 18), tissue expansion group (TE group, n = 23), and skin grafting group (SG group, n = 56). The location and size of the lesion, the number of operations, duration of each operation, preoperative preparation time, postoperative hospital stay, complications, and clinical outcomes of all patients were collected and assessed. RESULTS: The SE group had the most times of operation (3.9 and 6.0 for LCMN and GCMN, respectively), the shortest surgery length (56.3 min), and the shortest postoperative hospital stay (10.0d). The SE and SG groups required much less time to prepare for surgery and had a lower rate of complications than the TE group. During the 11.9-month median follow-up period, the SE and TE groups had better postoperative outcomes than the SG group. CONCLUSION: Each of the three operations has different advantages and disadvantages, and the specific surgical strategy should be decided based on the patient's unique circumstances.

LARP6 Regulates Keloid Fibroblast Proliferation, Invasion, and Ability to Synthesize Collagen.

Keloid is a skin fibroproliferative disease currently having no uniformly successful treatment. The lesion is composed of actively proliferating and collagen-overproducing fibroblasts. LARP6 is an RNA-binding protein able to regulate collagen synthesis in fibroblasts and to promote proliferation and invasion of tumor cells. To explore LARP6's likely functions in keloid pathogenesis, we performed immunohistochemistry staining on human keloid tissues and discovered markedly upregulated LARP6 expression in lesion fibroblasts compared with that of normal skin and hypertrophic scar tissues. In addition, the keloid tissue‒derived fibroblasts showed constitutive upregulation of LARP6 expression as well as significantly upregulated mRNA and protein expressions of type I collagen and enhanced cell proliferation and invasive behavior in cell culture system. Intriguingly, LARP6 knockdown by targeting with small interfering RNAs significantly inhibited type I collagen expression, proliferation, and invasion capability of keloid tissue‒derived fibroblasts relative to that of normal skin‒ and hypertrophic scar‒derived fibroblasts and control keloid tissue‒derived fibroblasts that were transfected with a scrambled small interfering RNA. In conclusion, the abnormally upregulated expression of LARP6 in fibroblasts may play an important role in the growth and invasive behavior of keloid lesions.

Gout-associated uric acid crystals induce tophi ulcerations and impair wound healing in a novel gouty ulcer model.

This study aimed to establish a novel gouty ulcer rat model induced by monosodium urate (MSU) deposition and preliminarily explored how MSU crystals affected wound healing. MSU crystals were subcutaneously injected into the back of rats to simulate tophi formation and ulceration. Ultrasound was used to detect the formation of gouty tophi. MSU crystal deposition and histopathological changes were analysed by haematoxylin-eosin staining. After the skin over the tophi became broken in the model group, a full-thickness tissue defect of the same area was made on the backs of the phosphate buffered saline (PBS) controls. On Days 3, 7, and 14 after wounding, the infiltration of neutrophils and macrophages and the expression of inflammatory markers, including interleukin-1ß (IL-1ß), tumour necrosis factor-α (TNF-α), and Nod-like receptor protein 3 (NLRP3), were examined by immunohistochemical staining and Western blotting, respectively. After the first subcutaneous injection in rats, local tissues showed redness and swelling, indicating inflammation on approximately Day 14. Tophi-like manifestations appeared on approximately Day 18. Tophi appeared heterogeneously hyperechoic by ultrasound. Swelling and redness in injured tissue areas increased on approximately Day 22, skin tissue necrosis was seen in a small area on approximately Day 26, and skin necrosis was enlarged and the tophi were ulcerated on approximately Day 32, accompanied by yellowish-white, chalky secretions. Haematoxylin and eosin staining showed dermal deposition of needle-like crystals with surrounding granulomatous inflammation. On Days 3, 7, and 14 after wounding, immunohistochemical staining showed the infiltration of neutrophils and macrophages, and the expression of inflammation-related proteins (IL-1ß, TNF-α, and NLRP3) were upregulated in gouty ulcers compared with those of PBS controls. The gouty ulcers were not completely healed by Day 14 compared with those in the PBS controls. In this study, a novel gouty ulcer rat model was constructed, which also revealed the existence of persistent chronic inflammation.