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101.

Background

Exosomes (Exos) and their contained microRNAs (miRNAs) have been emergingly recognized as key regulators in spanning biological processes, including proliferation and angiogenesis.

Aim of the study

This work investigates the function of Exos derived from adipose-derived mesenchymal stem cells (adMSCs) in viability of keloid fibroblasts (KFs).

Methods

Abnormally expressed miRNAs in keloid tissues were screened using the GEO dataset GSE113620. Meanwhile, miRNAs enriched in adMSC-Exos were predicted by bioinformatics system. Exos were extracted from acquired adMSCs and identified, which were co-incubated with KFs. Uptake of Exos by KFs was examined by fluorescence staining. Viability, proliferation, and apoptosis of KFs were analyzed by CCK-8, EdU labeling, and TUNEL assays. Conditioned medium of KFs was collected to stimulate angiogenesis of human umbilical vein endothelial cells (HUVECs). Binding between miR-7846-3p and neuropilin 2 (NRP2) was validated by luciferase assay. Protein levels of NRP2 and the Hedgehog pathway molecules were analyzed by western blot analysis.

Results

miR-7846-3p was predicted as an exosomal miRNA aberrantly expressed in keloids. AdMSC-Exos reduced viability, proliferation, and apoptosis resistance of KFs, and they blocked the angiogenesis of HUVECs. miR-7846-3p targeted NRP2 mRNA. miR-7846-3p upregulation in KFs suppressed NRP2 expression and reduced the expression of Hedgehog pathway molecules SHH, SMO, and GLI1. Either miR-7846-3p inhibition in Exos or NRP2 overexpression in KFs blocked the effects of Exos and restored the viability, proliferation, and pro-angiogenic role of KFs.

Conclusion

This work unravels that adMSC-Exos-derived miR-7846-3p suppresses NRP2 and inactivates the Hedgehog signaling to reduce proliferation and pro-angiogenic role of KFs.  相似文献   
102.

Background

Acne vulgaris (AV) is the most pervasive inflammatory disease of hair follicle and sebaceous gland in the dermatology department, and depressed scar (DS) is the most common and serious sequela of AV.

Aims

To explore the clinical value of CO2 dot matrix laser combined with platelet-rich plasma (PRP)-treated AV.

Methods

Total 81 patients with DS at the rear of AV from December 2018 to October 2019 were selected, randomly divided into observation group (OG, n = 39) and control group (CG, n = 42). Patients in the OG group were treated with CO2 dot matrix laser combined with PRP, and those in the CG group were treated with CO2 dot matrix laser. To observe clinical outcomes in both groups.

Results

According to experimental analysis, compared with the CG group, CO2 dot matrix laser combined with PRP can more strongly improve the clinical efficacy on patients, shorten the scar scabbing time and decrustation time, more effectively contributed to their scar repair, comfort, skin condition, psychological state and satisfaction, and reduced their pain. The subsequent follow-up results also showed that patients in the OG group experienced better quality of life. Moreover, according to the logistic regression analysis, the course of disease, scar degree, and staying up late were independent risk factors for the repair effect, and the repair method of CO2 dot matrix laser combined with PRP was an independent protection factor.

Conclusion

To sum up, CO2 dot matrix laser combined with PRP can strongly enhance the scar repair effect, psychological state, and life quality of patients with DS after AV, so it is worth popularizing in clinical practice.  相似文献   
103.

Background

To assess the effect and safety of probiotics for treating urticaria.

Methods

Randomized controlled trial (RCT) papers on the probiotics treatment published before May 2019 were retrieved from various databases like PubMed, EMbase, MEDLINE (Ovid), SCI-Hub, Springer, ClinicalKey, VIP, and CNKI. The treatment plan that we include are oral administration of single probiotic, multiple probiotics, and the combination of probiotics and antihistamines. Meta-analysis of the data was performed by RevMan 5.3 software.

Results

A total of nine RCT papers were included: four papers for oral administration of single probiotic, three papers for oral administration of multiple probiotics, and two papers for oral administration of a probiotic combined with antihistamines. The results of meta-analysis showed that the therapeutic effect of the probiotic group was significantly higher than the control group (placebo or antihistamines) (RR = 1.09, 95% CI: 1.03–1.16, p = 0.006). And compared with the placebo group, the therapeutic effect of single probiotic group was significantly improved (RR = 1.11, 95% CI: 1.01–1.21, p = 0.03). Regarding therapeutic effect, there was no statistically significant difference between the multiple probiotics group and placebo group (RR = 1.00, 95% CI: 0.94 ~ 1.07, p = 0.91); the therapeutic effect of single probiotic combined antihistamine group was significantly higher than the antihistamine group (RR = 1.13, 95% CI: 1.07–1.19, p < 0.0001). Regarding the incidence of adverse reactions, there was no significant difference between the probiotic group and the control group (p = 0.46).

Conclusion

The treatment plan of oral administration of probiotics has significant therapeutic effects on urticaria, but the therapeutic effects of the administration of multiple probiotics and the safety of probiotic therapy are still not yet obvious. Some large-scale, multi-centered RCT studies are needed in the future for clarification.  相似文献   
104.
Skin, as an exposed tissue, often suffers damage after exposure to radiotherapy and accidental events, which may lead to the formation of chronic refractory wounds. However, effective treatment options are usually limited for severe radiation-induced skin injury (RSI). Platelet-rich plasma (PRP) has been identified to promote wound healing, but whether a new generation of blood-derived biomaterial, injectable platelet-rich fibrin (i-PRF), is effective in repairing RSI remains unclear. In this study, blood was drawn from humans and Sprague–Dawley rats to prepare PRP and i-PRF, and the regenerative functions of PRP and i-PRF were investigated by exposing the dorsal skin of SD rats to local radiation (45 Gy) and exposing HDF-α cells and human umbilical vein endothelial cells (HUVECs) cells to X-rays (10 Gy). The healing effect of i-PRF on RSI was analysed by tube formation assay, cell migration and apoptosis assays, ROS assay, wound healing assay, histological characterisation and immunostaining. The results showed that exposure to high doses of radiation reduced cell viability, increased ROS levels and induced cell apoptosis, thereby causing dorsal trauma of rats. However, both PRP and i-PRF could resisted RSI, and they were capable of reducing inflammation and promoting angiogenesis and vascular regeneration. i-PRF has a higher concentration of platelets and platelet-derived growth factors, which has a more convenient preparation method and better repair effect and possesses a good application prospect for the repair of RSI.  相似文献   
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110.

Objective

The implications of the interval of staged bilateral total knee arthroplasty (TKA) procedures for postoperative complications and costs are not clear. We aimed to determine the optimal time interval between the two stages of bilateral TKA procedures under the enhanced recovery after surgery (ERAS) protocol.

Methods

This retrospective study of collected data included bilateral TKA cases under the ERAS protocol performed between 2018 and 2021 at the West China Hospital of Sichuan University. The staged time was subdivided into three groups according to the interval between the first TKA and second contralateral TKA: group 1: 2- to 6-month, group 2: 6- to 12-month, and group 3: >12 months. The primary outcome was the incidence of postoperative complications. The secondary outcomes were the length of hospital stay (LOS), hemoglobin (Hb) decrease, hematocrit (Hct) decrease, and albumin (Alb) decrease.

Results

We analyzed 281 patients who underwent staged bilateral TKAs between 2018 and 2021 at the West China Hospital of Sichuan University. Regarding postoperative complications, there were no statistically significant differences among the three groups (P = 0.21). For the mean LOS, the 6- to 12-month group had a significantly shorter LOS compared with the 2- to 6-month group (P < 0.01). There was also a significant decrease in Hct of the 2- to 6-month group compared with the 6- to 12-month group and the >12 months group (P = 0.02; P < 0.05, respectively).

Conclusion

Staging the second arthroplasty for more than a half year seems to offer a reduction in the rate of postoperative complications and LOS under ERAS protocol. ERAS shortens the interval of staged bilateral TKA by at least 6 months for patients who might receive their second surgery without the need to wait for an extended period.  相似文献   
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