Management of retroperitoneal appendiceal perforation: a case report.

Retroperitoneal appendiceal perforation presents unique challenges in surgical management due to the complex nature of the retroperitoneal space. We present a case of a 57-year-old male with retroperitoneal appendiceal perforation, characterized by the presence of a large amount of gas in the retroperitoneal space. Emergent laparoscopic surgery was performed to address the retroperitoneal involvement. In retroperitoneal appendiceal perforation, surgical intervention and postoperative drainage are of great significance to prevent septic shock. The interconnectedness of the retroperitoneal space with other body regions is highlighted, underscoring the potential for severe complications. This case emphasizes the need for a tailored approach to managing retroperitoneal appendiceal perforation, preventing potential complications associated with this condition.

Human skin specific long noncoding RNA HOXC13-AS regulates epidermal differentiation by interfering with Golgi-ER retrograde transport.

After a skin injury, keratinocytes switch from a state of homeostasis to one of regeneration leading to the reconstruction of the epidermal barrier. The regulatory mechanism of gene expression underpinning this key switch during human skin wound healing is enigmatic. Long noncoding RNAs (lncRNAs) constitute a new horizon in the understanding of the regulatory programs encoded in the mammalian genome. By comparing the transcriptome of an acute human wound and skin from the same donor as well as keratinocytes isolated from these paired tissue samples, we generated a list of lncRNAs showing changed expression in keratinocytes during wound repair. Our study focused on HOXC13-AS, a recently evolved human lncRNA specifically expressed in epidermal keratinocytes, and we found that its expression was temporally downregulated during wound healing. In line with its enrichment in suprabasal keratinocytes, HOXC13-AS was found to be increasingly expressed during keratinocyte differentiation, but its expression was reduced by EGFR signaling. After HOXC13-AS knockdown or overexpression in human primary keratinocytes undergoing differentiation induced by cell suspension or calcium treatment and in organotypic epidermis, we found that HOXC13-AS promoted keratinocyte differentiation. Moreover, RNA pull-down assays followed by mass spectrometry and RNA immunoprecipitation analysis revealed that mechanistically HOXC13-AS sequestered the coat complex subunit alpha (COPA) protein and interfered with Golgi-to-endoplasmic reticulum (ER) molecular transport, resulting in ER stress and enhanced keratinocyte differentiation. In summary, we identified HOXC13-AS as a crucial regulator of human epidermal differentiation.

Extracellular vesicles derived from fibroblasts induced with or without high glucose exert opposite effects on wound healing and angiogenesis.

Background: Communication between fibroblasts and endothelial cells is essential for skin wound repair and regeneration. Extracellular vesicles (EVs) are crucial for intracellular communication by transporting active molecules. However, whether EVs derived from diabetic fibroblasts can perform the nomal communication function is unclear. Here, we compared the effects of EVs from human skin fibroblasts (HSFs) induced with or without HG on the angiogenic function of endothelial cells and wound healing. Methods: We first collected EVs from HSFs cultured with normal glucose concentration (NG-EVs) or with HG concentration (HG-EVs) and applied them to treat human umbilical vein endothelial cells (HUVECs). The cells were divided into three groups: control group, NG-EVs group, and HG-EVs group. We then examined the proliferation, migration, apoptosis, and tube formation of HUVECs. To illustrate the mechanism, the expression of ß-catenin, GSK-3ß, and p-GSK-3ß was detected by western-blot. Finally, NG-EVs or HG-EVs were used to treat the wounds of mice to determine their role in wound closure. Results: By DNA content detection, Annexin V/PI staining, and EdU staining, we found that NG-EVs promoted HUVEC proliferation, while HG-EVs exhibited an opposite effect (p < 0.05). Scratch assay and tube formation assay demonstrated that NG-EV promoted angiogenesis in vitro, while HG-EVs showed negative impact (p < 0.05). The expressions of ß-catenin and p-GSK-3ß in HUVECs were enhanced by NG-EVs and decreased by HG-EVs (p < 0.05). Additionally, the in vivo experiment demonstrated that NG-EVs effectively promoted wound healing by locally enhancing blood supply and angiogenesis. In contrast, HG-EVs leaded to delayed wound closure and reduced blood supply and angiogenesis (p < 0.05). Conclusion: NG-EVs and HG-EVs exert opposite effects on wound healing and angiogenesis possibly by regulating GSK-3ß/ß-catenin signaling pathway. This research may provide a new treatment strategy for wound healing and illustrate the mechanism for impaired angiogenesis in diabetics.

MicroRNA-223 negatively regulates the osteogenic differentiation of periodontal ligament derived cells by directly targeting growth factor receptors.

BACKGROUND: MicroRNA (miRNA) is accepted as a critical regulator of cell differentiation. However, whether microRNA-223 (miR-223) could affect the osteogenic differentiation of periodontal ligament (PDL)-derived cells is still unknown. The aim of this study was to explore the mechanisms underlying the roles of miR-223 in the osteogenesis of PDL-derived cells in periodontitis. METHODS: Microarray analysis and real-time polymerase chain reaction (RT-PCR) were used to identify difference in miR-223 expression pattern between healthy and inflamed gingival tissue. The target genes of miR-223 were predicted based on Targetscan and selected for enrichment analyses based on Metascape database. The gain-and loss-of-function experiments were performed to discuss roles of miR-223 and growth factor receptor genes in osteogenic differentiation of PDL-derived cells. The target relationship between miR-223 and growth factor receptor genes was confirmed by a dual luciferase assay. Osteogenic differentiation of PDL-derived cells was assessed by Alizarin red staining, RT-PCR and western blot detection of osteogenic markers, including osteocalcin (OCN), osteopontin (OPN) and runt-related transcription factor 2 (Runx2). RESULTS: MiR-223 was significantly increased in inflamed gingival tissues and down-regulated in PDL-derived cells during osteogenesis. The expression of miR-223 in gingival tissues was positively correlated with the clinical parameters in periodontitis patients. Overexpression of miR-223 markedly inhibited PDL-derived cells osteogenesis, which was evidenced by reduced Alizarin red staining and osteogenic markers expressions. Furthermore, two growth factor receptor genes, including fibroblast growth factor receptor 2 (FGFR2) and transforming growth factor beta receptor 2 (TGFßR2), were revealed to be direct targets of miR-223 and shown to undergo up-regulation in PDL-derived cells during osteogenesis. Moreover, suppression of FGFR2 or TGFßR2 dramatically blocked PDL-derived cells osteogenic differentiation. CONCLUSIONS: Our study provides novel evidence that miR-223 can be induced by periodontitis and acts as a negative regulator of PDL-derived cells osteogenesis by targeting two growth factor receptors (TGFßR2 and FGFR2).

Identification of Key Genes and Pathways Associated with Oxidative Stress in Periodontitis.

Methods: The differentially expressed genes (DEGs) were identified using periodontitis-related microarray from the GEO database, and OS-genes were extracted from GeneCards database. The intersection of the OS-genes and the DEGs was considered as oxidative stress-related DEGs (OS-DEGs) in periodontitis. The Pearson correlation and protein-protein interaction analyses were used to screen key OS-genes. Gene set enrichment, functional enrichment, and pathway enrichment analyses were performed in OS-genes. Based on key OS-genes, a risk score model was constructed through logistic regression, receiver operating characteristic curve, and stratified analyses. Results: In total, 74 OS-DEGs were found in periodontitis, including 65 upregulated genes and 9 downregulated genes. Six of them were identified as key OS-genes (CXCR4, SELL, FCGR3B, FCGR2B, PECAM1, and ITGAL) in periodontitis. All the key OS-genes were significantly upregulated and associated with the increased risk of periodontitis. Functional enrichment analysis showed that these genes were mainly associated with leukocyte cell-cell adhesion, phagocytosis, and cellular extravasation. Pathway analysis revealed that these genes were involved in several signaling pathways, such as leukocyte transendothelial migration and osteoclast differentiation. Conclusion: In this study, we screened six key OS-genes that were screened as risk factors of periodontitis. We also identified multiple signaling pathways that might play crucial roles in regulating oxidative stress damage in periodontitis. In the future, more experiments need to be carried out to validate our current findings.

Integrative small and long RNA omics analysis of human healing and nonhealing wounds discovers cooperating microRNAs as therapeutic targets.

MicroRNAs (miR), as important epigenetic control factors, reportedly regulate wound repair. However, our insufficient knowledge of clinically relevant miRs hinders their potential therapeutic use. For this, we performed paired small and long RNA-sequencing and integrative omics analysis in human tissue samples, including matched skin and acute wounds collected at each healing stage and chronic nonhealing venous ulcers (VUs). On the basis of the findings, we developed a compendium (https://www.xulandenlab.com/humanwounds-mirna-mrna), which will be an open, comprehensive resource to broadly aid wound healing research. With this first clinical, wound-centric resource of miRs and mRNAs, we identified 17 pathologically relevant miRs that exhibited abnormal VU expression and displayed their targets enriched explicitly in the VU gene signature. Intermeshing regulatory networks controlled by these miRs revealed their high cooperativity in contributing to chronic wound pathology characterized by persistent inflammation and proliferative phase initiation failure. Furthermore, we demonstrated that miR-34a, miR-424, and miR-516, upregulated in VU, cooperatively suppressed keratinocyte migration and growth while promoting inflammatory response. By combining miR expression patterns with their specific target gene expression context, we identified miRs highly relevant to VU pathology. Our study opens the possibility of developing innovative wound treatment that targets pathologically relevant cooperating miRs to attain higher therapeutic efficacy and specificity.

Novel fusion peptides deliver exosomes to modify injectable thermo-sensitive hydrogels for bone regeneration.

Injectable thermo-sensitive hydrogels composed of small intestinal submucosa (SIS) with exosomes derived from bone marrow mesenchymal stem cells (BMSCs) are desired for bone regeneration. However, poor mechanical properties limit the clinical application of SIS hydrogels. Herein, the mechanical properties of SIS hydrogels incorporated with 3-(3,4-dihydroxyphenyl) propionic acid (CA) are assessed. The results show that the mechanical properties of SIS hydrogels are improved. In addition, the retention and stability of exosomes over time at the defect site are also challenges. Fusion peptides are designed by connecting collagen-binding domines (CBDs) of collagen type I/III with exosomal capture peptides CP05 (CRHSQMTVTSRL) directly or via rigid linkers (EAAAK). In vitro experiments demonstrate that fusion peptides are contribute to promoting the positive effect of exosomes on osteogenic differentiation of BMSCs. Meanwhile, the results of hydrogels combining exosomes and fusion peptides in the treatment of rat skull defect models reveal that fusion peptides could enhance the retention and stability of exosomes, thereby strengthen the therapeutic effect for skull defects. Therefore, SIS hydrogels with CA modified by fusion peptides and exosomes appear to be a promising strategy in bone regenerative medicine.

Calcium silicate accelerates cutaneous wound healing with enhanced re-epithelialization through EGF/EGFR/ERK-mediated promotion of epidermal stem cell functions.

BACKGROUND: Human epidermal stem cells (hESCs) play an important role in re-epithelialization and thereby in facilitating wound healing, while an effective way to activate hESCs remains to be explored. Calcium silicate (CS) is a form of bioceramic that can alter cell behavior and promote tissue regeneration. Here, we have observed the effect of CS on hESCs and investigated its possible mechanism. METHODS: Using a mouse full-thickness skin excision model, we explored the therapeutic effect of CS on wound healing and re-epithelialization. In vitro, hESCs were cultured with diluted CS ion extracts (CSIEs), and the proliferation, migration ability and stemness of hESCs were evaluated. The effects of CS on the epidermal growth factor (EGF), epidermal growth factor receptor (EGFR) and extracellular signal-related kinase (ERK) signaling pathway were also explored. RESULTS: In vivo, CS accelerated wound healing and re-epithelialization. Immunohistochemistry demonstrated that CS upregulated cytokeratin 19 and integrin ß1 expression, indicating that CS improved hESCs stemness. In vitro studies confirmed that CS improved the biological function of hESCs. And the possible mechanism could be due to the activation of the EGF/EGFR/ERK signaling pathway. CONCLUSION: CS can promote re-epithelialization and improve the biological functions of hESCs via activating the EGF/EGFR/ERK signaling pathway.

Non-surgical periodontal treatment improves rheumatoid arthritis disease activity: a meta-analysis.

OBJECTIVES: The aim of the meta-analysis was to clarify the efficacy of non-surgical periodontal treatment (NSPT) in improving rheumatoid arthritis (RA) disease activity. METHODS: A systematic literature search was conducted using the PubMed, Embase, and Cochrane databases up to October 2020. A total of nine studies were included for the comparison of RA-related indicator changes between the NSPT group and no treatment (NT) group. Mean differences (MD) and 95% confidence intervals (CI) were calculated for disease activity score (DAS28), erythrocyte sedimentation rate (ESR), tender joint counts (TJC), swollen joint counts (SJC), visual analogical scale (VAS), morning stiffness (MS), rheumatoid factor (RF), C-reactive protein (CRP), tumor necrosis factor α (TNF-α), and interleukin-6 (IL-6). RESULTS: NSPT induced significant reductions of DAS28 (MD: 0.61, 95% CI: 0.37, 0.85, P < 0.001), TJC (MD: 0.65, 95% CI: 0.37, 0.93, P < 0.001), SJC (MD: 0.67, 95% CI: 0.18, 1.17, P = 0.008), VAS (MD: 0.48, 95% CI: 0.08, 0.88, P = 0.02), and CRP (MD: 0.34, 95% CI: 0.07, 0.64, P = 0.01) in RA patients with periodontitis. Other parameters showed a trend toward reduction, but results were not statistically significant. CONCLUSIONS: This meta-analysis indicates that NSPT could improve RA activity as assessed by DAS28, TJC, SJC, VAS, and CRP. CLINICAL RELEVANCE: The results emphasize the effectiveness and need for periodontal diagnosis and periodontal therapy in rheumatoid arthritis patients to reduce disease activity.

Burns Impair Blood-Brain Barrier and Mesenchymal Stem Cells Can Reverse the Process in Mice.

Neurological syndromes are observed in numerous patients who suffer burns, which add to the economic burden of societies and families. Recent studies have implied that blood-brain barrier (BBB) dysfunction is the key factor that induces these central nervous system (CNS) syndromes in peripheral traumatic disease, e.g., surgery and burns. However, the effect of burns on BBB and the underlying mechanism remains, largely, to be determined. The present study aimed to investigate the effect of burns on BBB and the potential of umbilical cord-derived mesenchymal stem cells (UC-MSCs), which have strong anti-inflammatory and repairing ability, to protect the integrity of BBB. BBB permeability was evaluated using dextran tracer (immunohistochemistry imaging and spectrophotometric quantification) and western blot, interleukin (IL)-6, and IL-1ß levels in blood and brain were measured by enzyme-linked immunosorbent assay. Furthermore, transmission electron microscopy (TEM) was used to detect transcellular vesicular transport (transcytosis) in BBB. We found that burns increased mouse BBB permeability to both 10-kDa and 70-kDa dextran. IL-6 and IL-1ß levels increased in peripheral blood and CNS after burns. In addition, burns decreased the level of tight junction proteins (TJs), including claudin-5, occludin, and ZO-1, which indicated increased BBB permeability due to paracellular pathway. Moreover, increased vesicular density after burns suggested increased transcytosis in brain microvascular endothelial cells. Finally, administering UC-MSCs at 1 h after burns effectively reversed these adverse effects and protected the integrity of BBB. These results suggest that burns increase BBB permeability through both paracellular pathway and transcytosis, the potential mechanism of which might be through increasing IL-6 and IL-1ß levels and decreasing Mfsd2a level, and appropriate treatment with UC-MSCs can reverse these effects and protect the integrity of BBB after burns.

Regenerative and protective effects of dMSC-sEVs on high-glucose-induced senescent fibroblasts by suppressing RAGE pathway and activating Smad pathway.

BACKGROUND: Fibroblasts are crucial for supporting normal wound healing. However, the functional state of these cells is impaired in diabetics because of a high-glucose (HG) microenvironment. Small extracellular vesicles (sEVs) have emerged as a promising tool for skin wound treatment. The aim of this study was to investigate the effects of sEVs derived from human decidua-derived mesenchymal stem cells (dMSC-sEVs) on HG-induced human dermal fibroblast (HDF) senescence and diabetic wound healing and explore the underlying mechanism. METHODS: We first created a HDF senescent model induced by HG in vitro. dMSC-conditioned medium (dMSC-CM) and dMSC-sEVs were collected and applied to treat the HG-induced HDFs. We then examined the proliferation, migration, differentiation, and senescence of these fibroblasts. At the same time, the expressions of RAGE, p21 RAS, Smad2/3, and pSmad2/3 were also analyzed. Furthermore, pSmad2/3 inhibitor (SB431542) was used to block the expression of pSmad2/3 to determine whether dMSC-sEVs improved HDF senescence by activating Smad pathway. Finally, we assessed the effect of dMSC-sEVs on diabetic wound healing. RESULTS: The HG microenvironment impaired the proliferation, migration, and differentiation abilities of the HDFs and accelerated their senescence. dMSC-CM containing sEVs improved the proliferation and migration abilities of the HG-induced fibroblasts. dMSC-sEVs internalized by HG-induced HDFs not only significantly promoted HDF proliferation, migration, and differentiation, but also improved the senescent state. Furthermore, dMSC-sEVs inhibited the expression of RAGE and stimulated the activation of Smad signaling pathway in these cells. However, SB431542 (pSmad2/3 inhibitor) could partially alleviate the anti-senescent effects of dMSC-sEVs on HG-induced HDFs. Moreover, the local application of dMSC-sEVs accelerated collagen deposition and led to enhanced wound healing in diabetic mice. The detection of PCNA, CXCR4, α-SMA, and p21 showed that dMSC-sEVs could enhance HDF proliferation, migration, and differentiation abilities and improve HDF senescent state in vivo. CONCLUSION: dMSC-sEVs have regenerative and protective effects on HG-induced senescent fibroblasts by suppressing RAGE pathway and activating Smad pathway, thereby accelerating diabetic wound healing. This indicates that dMSC-sEVs may be a promising candidate for diabetic wound treatment.

Regenerative and protective effects of calcium silicate on senescent fibroblasts induced by high glucose.

Diabetic wounds are a common complication of diabetes and therefore a pressing issue for clinicians. High-glucose (HG)-induced fibroblast senescence is mainly responsible for delayed wound healing. Calcium silicate (CS), a kind of bioceramic, is thought to have regenerative properties. The aim of this study was to determine the regenerative and protective effects of CS on senescent fibroblasts induced by HG. Fibroblasts were passaged five times and treated with HG and CS. Compared with the normal glucose (NG) group, the proliferation, migration, and differentiation capacity of HG-induced fibroblasts significantly decreased (P < .05). After treatment with CS, the functions of HG-induced senescent fibroblasts were partly restored (P < .05). The mechanism of the regenerative and protective effects of CS may be related to the decreased reactive oxygen species generation, improved senescent state (SA-ß-gal expression decreased), up-regulated expression of Smad2 and phosphorylated Smad2, and down-regulated expression of p16, p21, and p53. An in vivo experiment also demonstrated that CS had a therapeutic effect on diabetic wounds via differentiation of fibroblasts into myofibroblasts and enhanced collagen deposition. These results indicate that CS may be a promising candidate for diabetic wound therapy.

Therapeutic angiogenesis using stem cell-derived extracellular vesicles: an emerging approach for treatment of ischemic diseases.

Ischemic diseases, which are caused by a reduction of blood supply that results in reduced oxygen transfer and nutrient uptake, are becoming the leading cause of disabilities and deaths. Therapeutic angiogenesis is key for the treatment of these diseases. Stem cells have been used in animal models and clinical trials to treat various ischemic diseases. Recently, the efficacy of stem cell therapy has increasingly been attributed to exocrine functions, particularly extracellular vesicles. Extracellular vesicles are thought to act as intercellular communication vehicles to transport informational molecules including proteins, mRNA, microRNAs, DNA fragments, and lipids. Studies have demonstrated that extracellular vesicles promote angiogenesis in cellular experiments and animal models. Herein, recent reports on the use of extracellular vesicles for therapeutic angiogenesis during ischemic diseases are presented and discussed. We believe that extracellular vesicles-based therapeutics will be an ideal treatment method for patients with ischemic diseases.

Identification and characterization of the biochemical function of Agrobacterium T-complex-recruiting protein Atu5117.

Atu5117 from Agrobacterium tumefaciens is a highly conserved protein with a putative nucleotidyltransferase domain in its N-terminal region and a putative higher eukaryotes and prokaryotes nucleotide-binding domain in its C-terminal region. This protein has been shown to be a T-complex-recruiting protein that can recruit T-complex from the cytosol to the polar VirB/D4 type IV secretion system (T4SS). However, the biochemical function of Atu5117 is still unknown. Here, we show that Atu5117 is a (d)NTPase. Although no proteins with nucleotidyltransferase and higher eukaryotes and prokaryotes nucleotide-binding domains were identified as (d)NTPases, Atu5117 was able to convert all eight canonical NTPs and dNTPs to NDP, dNDP and inorganic phosphate in vitro, and required Mg(2+) for its (d)NTPase activity. The kinetic parameters of Atu5117 (d)NTPase for eight substrates were characterized. Kinetic data showed that Atu5117 (d)NTPase preferred ATP as its substrate. The optimal conditions for (d)NTPase activity of Atu5117 were very similar to those required for Agrobacterium tumorigenesis. The kinetic parameters of (d)NTPase of Atu5117 for all four canonical NTPs were in the same orders of magnitude as the kinetic parameters of the ATPases identified in some components of the VirB/D4 T4SS. These results suggest that Atu5117 might function as an energizer to recruit T-complex to the T4SS transport site.