A high resolution reaction microscope with universal two-region time-focusing method.

This paper presents a novel reaction microscope designed for ion-atom collision investigations, established at the Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou, China. Its time-of-flight (TOF) spectrometer employs an innovative flight-time focusing method consisting of two acceleration regions, providing optimal time focusing conditions for charged fragments with diverse initial velocities. The TOF spectrometer's axis intentionally tilts by 12° relative to the ion beam direction, preventing potential obstructions from the TOF grid electrodes. The introduced focusing method allows for a flexible time-focusing TOF spectrometer design without restricting the length ratio of the two regions. In addition, this configuration in our case significantly suppresses noise on the recoil ion detector produced by residual gas in the ion beam trajectory, which is a considerable challenge in longitudinal spectrometers. In a test experiment on the single electron capture reaction involving 62.5 keV/u He2+ ions and a helium atomic beam, the recoil longitudinal momentum resolution achieved 0.068 atomic units. This novel configuration and successful test run show excellent precision for ion-atom collision studies.

[Effect and mechanism of human adipose-derived stem cell exosomes on diabetic peripheral neuropathy].

Objective: To investigate the changes of artemin protein expression in diabetic peripheral neuropathy (DPN) and to explore the regulatory effect of human adipose-derived stem cell (ADSC) exosomes on the change of artemin protein expression. Methods: This research was a prospective observational clinical research combined with experimental research. Thirteen DPN patients (9 males and 4 females, aged 32 to 68 years) who were admitted to the First Affiliated Hospital of Air Force Medical University (hereinafter referred to as our hospital) from May 2022 to October 2023 and met the inclusion criteria were selected as DPN group, and 5 non-diabetes patients (4 males and 1 female, aged 29 to 61 years) who were admitted to our hospital in the same period of time and met the inclusion criteria were selected as control group. The toe nerve or sural nerve tissue in the abandoned tissue after debridement or amputation of patients in the two groups was collected. The pathological changes of nerve tissue were observed after hematoxylin-eosin staining; the protein expressions of S100ß and artemin in nerve tissue were observed after immunofluorescence staining, and the artemin protein expression was quantified; the protein and mRNA expressions of artemin were detected by Western blotting and real-time fluorescent quantitative reverse transcription polymerase chain reaction, respectively (the sample number in DPN group and control group was 13 and 5, respectively). Twelve male C57BL/6 mice aged 3 to 5 days were collected to isolate Schwann cells, and the cells were divided into conventional culture group cultured routinely, high glucose alone group (cultured with high concentration of glucose solution only), and high glucose+exosome group (cultured with high concentration of glucose solution and extracted human ADSC exosomes). After 24 hours of culture, the cell proliferation activity was detected by cell counting kit 8 (n=6). After 48 hours of culture, the protein expression of artemin was detected by Western blotting (n=3). Results: Compared with those in control group, the neural supporting cells decreased and the inflammatory cells increased in the nerve tissue of patients in DPN group, showing typical manifestations of nerve injury. Immunofluorescence staining showed that compared with those in control group, the nuclei was more, and the protein expression of S100ß was lower in nerve tissue of patients in DPN group. The protein expression of artemin in nerve tissue of patients in DPN group was 71±31, which was significantly lower than 1 729±62 in control group (t=76.92, P<0.05). Western blotting detection showed that the protein expression of artemin in nerve tissue of patients in DPN group was 0.74±0.08, which was significantly lower than 0.97±0.06 in control group (t=5.49, P<0.05). The artemin mRNA expression in nerve tissue of patients in DPN group was significantly lower than that in control group (t=7.65, P<0.05). After 24 hours of culture, compared with that in conventional culture group, the proliferation activities of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the proliferation activity of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). After 48 hours of culture, compared with those in conventional culture group, the protein expressions of artemin of Schwann cells in high glucose alone group and high glucose+exosome group were significantly decreased (P<0.05); compared with that in high glucose alone group, the protein expression of artemin of Schwann cells in high glucose+exosome group was significantly increased (P<0.05). Conclusions: The protein expression of artemin in nerve tissue of DPN patients is lower than that in normal nerve tissue, which may be related to the reduction of proliferation activity of Schwann cells by high glucose. Human ADSC exosomes may improve the proliferation activity of Schwann cells by increasing artemin protein expression, thereby delaying the progression of DPN.

Validation of an automated dispensing system for subsequent dose dispensing of different radionuclides.

BACKGROUND: Automated dispensing systems (ADSs) for radiopharmaceuticals have been developed to reduce the radiation exposure of personnel, to improve the accuracy of the dispensed dose and to limit the microbiological contamination. However, before implementing such systems, validation according to various applicable guidelines is necessary to ensure safety and quality. Here we present the selection, validation and implementation of the PT459R2 from manufacturer Lynax s.r.o. as a guidance protocol for validation according to GMP and GRPP guidelines. Validation included linearity accuracy and precision of the internal scintillation detector for different isotopes and microbiological validation for aseptic procedures. RESULTS: The ADS can dispense accurate doses in the following linear range: 1000-10,000 MBq for lutetium-177, 20-74 MBq for zirconium-89, 100-1000 MBq for gallium-68 and 100-2000 MBq for fluorine-18. The maximum bias is 2.35% and the maximum coefficient of variation is 3.03% which meets the acceptance criteria of < 5%. Furthermore, the ADS does not affects the GMP class A environment in a laminar airflow cabinet and can dispense aseptically. In addition, radiation exposure is acceptable and data integrity is preserved. CONCLUSION: The PT459R2 ADS met all the requirements from our performance qualification and is therefore suitable for daily routine use in our center. Our approach can be used as a guidance for PQ of an ADS in a Radiopharmacy according to GMP and GRPP guidelines.

[Research advances on the role of Schwann cells in diabetic peripheral neuropathy].

Diabetic peripheral neuropathy (DPN) is one of the common chronic complications of diabetes, resulting in neuropathy of spinal nerve, cranial nerve, and vegetative nerve. Diabetic distal symmetric multiple neuropathy is the most representative lesion of DPN, including symptoms of bilateral limbs pain, numbness, and paresthesia, etc. DPN is one of the main reasons causing diabetic foot ulcer (DFU). Schwann cells (SCs) are the primary glia cells of the peripheral nervous system, which play very important role in repairing after nerve injury. As the target cells of chronic hyperglycemia, SCs' functions, including the formation of myelin sheath, the secretion of neurotrophic factors, energy supplying for the axon, and the guidance of axon regeneration, etc., are damaged under the action of high glucose. The destroyed functions of SCs can inhibit the repair of damaged nerves and accelerate the progress of DPN. Therefore, if the damage of high glucose to SCs can be effectively reduced, it will provide a new way for the treatment of DPN and DFU and reduce the morbidity of DFU. This review focuses on the function of SCs and its relationship with DPN.

Class III Antiarrhythmics and Periprocedural Torsades de Pointes.

This case series describes 2 women on prolonged therapy with class III antiarrhythmics who developed torsades de pointes polymorphic ventricular tachycardia in the setting of catheter ablation for atrial fibrillation as a result of QTc prolonging factors. Clinicians must exercise increased vigilance in the perioperative period in patients on QTc-prolonging medications. (Level of Difficulty: Intermediate.).

[A prospective randomized controlled study of antibiotic bone cement in the treatment of diabetic foot ulcer].

Objective: To investigate the clinical effects and related mechanism of antibiotic bone cement in treating diabetic foot ulcer (DFU). Methods: A prospective randomized controlled study was conducted. From August 2020 to August 2022, 24 patients with DFU who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University. According to the block randomization, the patients were divided into 2 groups, with 12 patients in each group. In antibiotic bone cement group, there were 7 male and 5 female patients, aged (64±8) years, with the ulcer area of (41±21) cm2. In silver sulfadiazine group, there were 8 male and 4 female patients, aged (62±8) years, with the ulcer area of (38±19) cm2. Under the condition of ensuring the patency of at least one main inferior genicular artery in each patient, the continuous vacuum sealing drainage was performed for 3-5 days after thorough debridement. Thereafter, the wounds in antibiotic bone cement group were treated with gentamicin-laden bone cement, and the wounds in silver sulfadiazine group were treated with silver sulfadiazine cream for dressing change. After 3 weeks of dressing change, the wound was covered with split-thickness skin graft from the lateral thigh on the affected side. Before debridement and after 3 weeks of dressing change, the blood flow intensities of wound tissue and normal skin tissue in foot were measured using laser Doppler flowmeter, and then, the percentage of relative blood flow intensity of wound and the change rate of blood flow intensity were calculated. After 3 weeks of dressing change, the wound margin tissue was taken, the number of CD31-positive neovascular and the vascular morphology were observed and detected by immunohistochemical staining, the morphology of blood vessels surrounded by CD31 and α-smooth muscle actin (α-SMA) double-positive cells was observed by immunofluorescence staining, the cell proliferation activity was evaluated by immunofluorescence staining (denoted as the ratio of Ki67 positive cells), and the protein expression of vascular endothelial growth factor receptor 2 (VEGFR2) was detected by Western blotting. The skin graft survival was observed 3-5 days after skin grafting, and the wound healing time was recorded. Data were statistically analyzed with independent sample t test and Fisher's exact probability test. Results: The percentages of relative blood flow intensity of wounds of patients before debridement were similar between the two groups (P>0.05). After 3 weeks of dressing change, the percentage of relative blood flow intensity of wounds and the change rate of blood flow intensity of patients in antibiotic bone cement group were (44.7±2.0)% and (129±12)%, respectively, which were significantly higher than (28.3±1.2)% and (41±8)% in silver sulfadiazine group (with t values of 24.15 and 20.97, respectively, P<0.05). After 3 weeks of dressing change, compared with those in silver sulfadiazine group, the number of CD31-positive neovascular in the wound margin tissue of patients in antibiotic bone cement group was significantly increased (t=33.81, P<0.05) with larger diameter and more regular arrangement, the vascular wall continuity surrounded by CD31 and α-SMA double-positive cells was better, and the ratio of Ki67 positive cells and protein expression of VEGFR2 were significantly increased (with t values of 40.97 and 47.38, respectively, P<0.05). On post skin grafting day 3-5, all the patients in antibiotic bone cement group and 8 patients in silver sulfadiazine group had good skin graft survival, while 4 patients in silver sulfadiazine group showed spotted/patchy skin graft necrosis, which were cured after corresponding treatment. The wound healing time of patients in antibiotic bone cement group was (47.1±2.9) d, which was significantly shorter than (58.8±2.3) d in silver sulfadiazine group (t=10.86, P<0.05). Conclusions: Compared with silver sulfadiazine, clinical application of antibiotic bone cement for treating DFU has the characteristics of accelerating wound healing and better reconstruction of local blood flow, which may be closely related to the fact that antibiotic bone cement promoted the local angiogenesis effectively in the wound through enhancing the expression of VEGFR2.

[Effects of the anterolateral thigh chimeric perforator flaps in repairing complex wounds of foot and ankle].

Objective: To investigate the effects of anterolateral thigh chimeric perforator flap in repairing complex wounds of foot and ankle. Methods: A retrospective observational study was conducted. From May 2018 to June 2022, 23 patients who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University to repair complex wounds of foot and ankle with anterolateral thigh chimeric perforator flaps, including 15 males and 8 females, aged from 20 to 66 years. The wounds were all accompanied by bone exposure and defects, and were complicated with varying degrees of infection. All patients underwent debridement and continuous vacuum sealing drainage treatment for 1 week in stage Ⅰ, with the skin and soft tissue defect area after debridement being 10 cm×5 cm to 22 cm×7 cm. In stage Ⅱ, the anterolateral thigh chimeric perforator flap was used to cover the defective wound, of which the muscle flap was used to fill the deep invalid cavity of the ankle joint or cover bone and internal fixation exposures, and the skin flap was used to cover the superficial wound, with the area of the skin flap ranging from 11 cm×6 cm to 23 cm×8 cm, and the area of the muscle flap ranging from 4.0 cm×2.5 cm to 8.0 cm×5.0 cm. The survival of the flap was observed after operation. During follow-up, the color, texture, appearance, and complications of the flap were observed, the function of ankle joint and its range of dorsiflexion motion and plantar flexion motion were measured, and the scar hyperplasia and muscular hernia in donor area were observed. Results: Ecchymosis and epidermal necrosis occurred at the tip of the flap in 1 patient on 5 days after operation and healed after dressing change for 1 week; the other flaps of patients survived successfully. After 6 to 40 months of follow-up, the color, texture, and shape of flaps were good, but 1 patient was not satisfied with the shape of the flap because of flap swelling; the ankle joint movement was basically normal, the dorsiflexion motion was 15-30°, and the plantar flexion motion was 20-45°; the scar hyperplasia in the donor area of the flap was not obvious, and no muscular hernia occurred. Conclusions: The anterolateral thigh chimeric perforator flap can effectively fill the deep invalid cavity of ankle joint and cover the superficial wound at the same time, with minimal damage to the donor site. So it is an ideal flap for repairing the complex wounds of foot and ankle.

Clinical evaluation of hysterectomy for the treatment of invasive mole in Southern Vietnam.

OBJECTIVE: This study aimed to determine the rate of salvage chemotherapy and review associated factors in invasive mole patients treated by primary or delayed hysterectomy. PATIENTS AND METHODS: This study was carried out at the Tu Du Hospital, where a total of 189 patients were diagnosed with invasive mole based on histologic examination by hysterectomy between 01/2016 to 12/2020. We used the life table method to estimate the cumulative rate. We applied the Cox proportional hazard model to determine the factors associated with the need for salvage chemotherapy. RESULTS: At 12-month follow-up, 47 patients had required salvage chemotherapy. The incidence was 24.87% (95% CI: 18.88-31.66). Applying the multivariate model, prophylactic chemotherapy (HR = 2.75, 95% Cl: 1.20-6.30) and two weeks postoperative hCG value greater than 1,900 mIU/mL (HR = 4.30, 95% Cl: 2.08-8.87) increased the risk of requiring salvage chemotherapy. Postoperative chemotherapy decreased the risk of requiring salvage chemotherapy (HR = 0.43, 95% Cl: 0.22-0.83). CONCLUSIONS: Hysterectomy can be considered safe and effective in treating invasive mole patients. Although patients were treated by hysterectomy, 24.87% of patients needed salvage chemotherapy to achieve remission. This study affirms the malignant nature of invasive mole, a subtype of gestational trophoblastic neoplasia (GTN). It is not purely a local invasion of molar villi. Postoperative chemotherapy plays an essential role in reducing the risk of requiring salvage chemotherapy.

[Comparison of efficacy and safety of transurethral thulium laser vapoenucleation of prostate and transurethral thulium laser enucleation of prostate in the treatment of benign prostatic hyperplasia].

Objective: To compare early outcomes between transurethral thulium laser vapoenucleation of prostate and transurethral thulium laser enucleation of prostate for the treatment of benign prostatic hyperplasia (BPH). Methods: Retrospective analysis was conducted on the clinical data of 1 638 BPH patients admitted to the Department of Urology of Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine from January 2018 to December 2021. There were 916 patients underwent transurethral thulium laser vapoenucleation of prostate (ThuVEP group) and 722 patients underwent transurethral thulium laser enucleation of prostate (ThuLEP group). The operation time, eliminated tissue weight, surgical complications, duration of post-operative catheter implantation were compared between the two groups. The improvement of International Prostate Symptom Score (IPSS), Quality of Life Index (QoL), maximum uroflow rate (Qmax) and post-void residual urine volume (PVR) at 1 month after operation was compared between the two groups. Results: There were no significant differences in age, preoperative and 1-month postoperative prostate volume, IPSS score, QoL score, Qmax, and PVR between the ThuVEP and ThuLEP group (all P>0.05). There were no significant differences in perioperative indicators such as operation time, cutting or enucleation time, tissue crushing time, tissue weight, hemoglobin change, catheter indwelling time, and postoperative hospital stay between ThuVEP group and ThuLEP group (all P>0.05). The incidence of minor gross hematuria after extubation in the ThuVEP group was 7.8% (56/916), which was lower than 9.4% (65/722) in the ThuLEP group (P=0.026); the incidence of temporary incontinence at 1 month after surgery was 5.2% (38/916) in ThuVEP group, lower than 11.9% (86/722) in ThuLEP group (P<0.001). A total of 3 patients (0.4%) in ThuLEP group required operative intervention for severe post-operation bleeding, but none of ThuVEP group suffered from this kind of surgical complications. Conclusions: ThuVEP has similar efficacy with ThuLEP for the treatment of BPH. ThuVEP can significantly reduce the incidence of post-operation temporary urine incontinence, and has much superiority in stanching bleeding.

The Mediator complex regulates enhancer-promoter interactions.

Enhancer-mediated gene activation generally requires physical proximity between enhancers and their target gene promoters. However, the molecular mechanisms by which interactions between enhancers and promoters are formed are not well understood. Here, we investigate the function of the Mediator complex in the regulation of enhancer-promoter interactions, by combining rapid protein depletion and high-resolution MNase-based chromosome conformation capture approaches. We show that depletion of Mediator leads to reduced enhancer-promoter interaction frequencies, which are associated with a strong decrease in gene expression. In addition, we find increased interactions between CTCF-binding sites upon Mediator depletion. These changes in chromatin architecture are associated with a redistribution of the Cohesin complex on chromatin and a reduction in Cohesin occupancy at enhancers. Together, our results indicate that the Mediator and Cohesin complexes contribute to enhancer-promoter interactions and provide insights into the molecular mechanisms by which communication between enhancers and promoters is regulated.

First CLAS12 Measurement of Deeply Virtual Compton Scattering Beam-Spin Asymmetries in the Extended Valence Region.

Deeply virtual Compton scattering (DVCS) allows one to probe generalized parton distributions describing the 3D structure of the nucleon. We report the first measurement of the DVCS beam-spin asymmetry using the CLAS12 spectrometer with a 10.2 and 10.6 GeV electron beam scattering from unpolarized protons. The results greatly extend the Q^{2} and Bjorken-x phase space beyond the existing data in the valence region and provide 1600 new data points measured with unprecedented statistical uncertainty, setting new, tight constraints for future phenomenological studies.

The association between chronic venous disease and knee osteoarthritis.

OBJECTIVE: Chronic venous disease (CVD) and knee osteoarthritis (KOA) are two common diseases in the elderly. Both share common risk factors, such as age, sex, and obesity, and are believed to be associated with inflammatory conditions and venous stasis. However, studies of the association between CVD and KOA are limited, especially in the elderly. To investigate the association between CVD and KOA and their effects on pain and functional status in the elderly at the Rheumatology Clinic of University Medical Center Ho Chi Minh City (HCMC). PATIENTS AND METHODS: This cross-sectional study included 222 elderly patients (aged ≥60 years) at the Rheumatology Clinic of University Medical Center HCMC from December 2019 to June 2020, including 167 with and 55 without KOA. Patient data were collected for both groups, including demographics, symptoms, clinical signs, and diagnostic tests for KOA and CVD, including knee radiographs and duplex scanning of the lower extremity veins. RESULTS: CVD was a common comorbidity among elderly patients with KOA (73.65% vs. 58.18%; p = 0.030). CVD symptoms did not differ significantly between patients with and without KOA. After adjusting for age, sex, body mass index, and some comorbid conditions, the differences in CVD incidence between the groups remained significant (odds ratio = 2.46, 95% confidence interval: 1.20-5.06; p = 0.014). Visual Analog Scale and Western Ontario and McMaster Universities Osteoarthritis Index pain scores were higher in elderly patients with KOA and CVD. CONCLUSIONS: CVD is common in elderly patients with KOA. While age, sex, and weight are risk factors for both conditions, there is an independent association between them. Patients comorbid with KOA and CVD have more pain and limited functional status.

CTCF, BEAF-32, and CP190 are not required for the establishment of TADs in early Drosophila embryos but have locus-specific roles.

The boundaries of topologically associating domains (TADs) are delimited by insulators and/or active promoters; however, how they are initially established during embryogenesis remains unclear. Here, we examined this during the first hours of Drosophila embryogenesis. DNA-FISH confirms that intra-TAD pairwise proximity is established during zygotic genome activation (ZGA) but with extensive cell-to-cell heterogeneity. Most newly formed boundaries are occupied by combinations of CTCF, BEAF-32, and/or CP190. Depleting each insulator individually from chromatin revealed that TADs can still establish, although with lower insulation, with a subset of boundaries (~10%) being more dependent on specific insulators. Some weakened boundaries have aberrant gene expression due to unconstrained enhancer activity. However, the majority of misexpressed genes have no obvious direct relationship to changes in domain-boundary insulation. Deletion of an active promoter (thereby blocking transcription) at one boundary had a greater impact than deleting the insulator-bound region itself. This suggests that cross-talk between insulators and active promoters and/or transcription might reinforce domain boundary insulation during embryogenesis.

Chimeric Antigen Receptor-Natural Killer Cells: A New Breakthrough in the Treatment of Solid Tumours.

Natural killer (NK) cells can quickly and directly eradicate tumour cells without recognising tumour-specific antigens. NK cells also participate in immune surveillance, which arouses great interest in the development of novel cancer therapies. The chimeric antigen receptor (CAR) family is composed of receptor proteins that give immune cells extra capabilities to target specific antigen proteins or enhance their killing effects. CAR-T cell therapy has achieved initial success in haematological tumours, but is prone to adverse reactions, especially with cytokine release syndrome in clinical applications. Currently, CAR-NK cell therapy has been shown to successfully kill haematological tumour cells with allogeneic NK cells in clinical trials without adverse reactions, proving its potential to become an off-the-shelf product with broad clinical application prospects. Meanwhile, clinical trials of CAR-NK cells for solid tumours are currently underway. Here we will focus on the latest advances in CAR-NK cells, including preclinical and clinical trials in solid tumours, the advantages and challenges of CAR-NK cell therapy and new strategies to improve the safety and efficacy of CAR-NK cell therapy.

[LncRNA SNHG8 inhibits miR-494-3p expression to alleviate cerebral ischemia-reperfusion injury in mice].

OBJECTIVE: To explore the mechanism by which LncRNA SNHG8 regulates miR-494-3p expression to alleviate cerebral ischemia-reperfusion injury. METHODS: A mouse model of cerebral ischemia-reperfusion injury was established, and TTC staining was used to determine the infarct area; ELISA was used to detect the contents of the inflammatory factors IL-1ß, IL-6 and TNF-α in the brain tissue, and RT-qPCR was performed to detect the expression levels of LncRNA MALAT1 and miR-155-5p. A microglial cell model overexpressing LncRNA SNHG8 was exposed to oxygen-glucose deprivation/reoxygenation (OGD/R), and inflammatory reaction and apoptosis of the cells were detected using ELISA and flow cytometry. A luciferase reporter assay was used to detect the targeting relationship between LncRNA SNHG8 and miR-494-3p. We further constructed a microglial cell model overexpressing both LncRNA SNHG8 the miR-494-3p, and examined inflammatory reactions and apoptosis of the cells following OGD/R exposure. RESULTS: In the mouse model of cerebral ischemia-reperfusion injury, the contents of inflammatory factors IL-1ß, IL-6 and TNF-α increased significantly in the brain tissue (P < 0.001), where LncRNA SNHG8 expression was lowered (P < 0.01) and miR-494-3p expression increased significantly (P < 0.01). In the microglial cells, overexpression of LncRNA SNHG8 significantly inhibited the inflammatory reaction and apoptosis following OGD/R exposure (P < 0.01), and overexpression of LncRNA SNHG8 strongly inhibited the expression of miR-494-3p (P < 0.01). Overexpression of miR-494-3p in microglia overexpressing SNHG8 partially promoted inflammatory reaction and cell apoptosis in response to OGD/R (P < 0.05). CONCLUSION: LncRNA SNHG8 can improve cerebral ischemia-reperfusion injury in mice by inhibiting the expression of miR-494-3p and suppressing inflammatory reactions and apoptosis of the microglia.

[Sulforaphane reverses Aß fiber-mediated M1 type microglia polarization and neuroinflammation-mediated necroptosis of neural stem cells by downregulating the MAPK/NF-κB signaling pathways].

OBJECTIVE: To explore the effects of sulforaphane (SFN) and Aß25-35 fibers (fAß25-35) on M1/M2 polarization of BV-2 cells and neuroinflammation-mediated programmed necrosis of neural stem cells. METHODS: BV-2 cells treated with different concentrations of fAß25-35 and SFN were examined for changes in cell viability using the CCK-8 kit. The effect of fAß25-35 alone or in combination with SFN or SB203580 on expressions of IL-6 and TNF-α mRNA and proteins were assessed in BV-2 cells using RT-qPCR and ELISA. CD16/32 and CD206 in the treated cells were analyzed with flow cytometry, and the cellular expressions of p-p38 and p-p65 protein were detected with Western blotting. C17.2 cells co-cultured with BV-2 cells for 24 h were examined for p-mlkl protein expression using Western blotting. RESULTS: fAß25-35 at the concentration of 6.25 µmol/L significantly increased the viability of BV-2 cells (P < 0.01) whereas fAß25-35 beyond 50 µmol/L decreased the cell viability (P < 0.0001). Treatment of BV-2 cells with SFN below 10 µmol/L for 24 h did not significant affect the cell viability (P > 0.05). BV-2 cells treated with fAß25-35 alone, as compared with the cells in the other 3 groups, showed significantly increased IL-6 and TNF-α mRNA and protein expressions (P < 0.001), enhanced CD16/32 expression (P < 0.05), lowered CD206 expression (P < 0.01), and increased protein expressions of p-p38 and p- p65 (P < 0.01). C17.2 cells co-cultured with BV-2 cells treated with fAß25-35, compared with the combined treatments, showed a significant reduction in the protein expression of p-mlkl (P < 0.05). CONCLUSION: SFN reverses M1 type microglia polarization and neuroinflammation-mediated programmed necrosis of neural stem cells by downregulating the MAPK/NF-κB signaling pathway in Aß25-35-activated BV-2 cells.

[Effects of exosomes from hepatocyte growth factor-modified human adipose mesenchymal stem cells on full-thickness skin defect in diabetic mice].

Objective: To investigate the effects and mechanism of exosomes from hepatocyte growth factor (HGF)-modified human adipose mesenchymal stem cells (ADSCs) on full-thickness skin defect wounds in diabetic mice. Methods: The experimental study method was adopted. Discarded adipose tissue of 3 healthy females (10-25 years old) who underwent abdominal surgery in the Department of Plastic Surgery of First Affiliated Hospital of Air Force Medical University from February to May 2021 was collected, and primary ADSCs were obtained by collagenase digestion method and cultured for 7 days. Cell morphology was observed by inverted phase contrast microscope. The ADSCs of third passage were transfected with HGF lentivirus and cultured for 5 days, and then the fluorescence of cells was observed by imaging system and the transfection rate was calculated. The exosomes of ADSCs of the third to sixth passages and the HGF transfected ADSCs of the third to sixth passages were extracted by density gradient centrifugation, respectively, and named, ADSC exosomes and HGF-ADSC exosomes. The microscopic morphology of exosomes was observed by transmission electron microscopy, and the positive expressions of CD9, CD63, and CD81 of exosomes were detected by flow cytometry, respectively. Twenty-four 6-week-old male Kunming mice were selected to make the diabetic models, and full-thickness skin defect wounds were made on the backs of mice. According to the random number table method, the mice were divided into phosphate buffer solution (PBS) group, HGF alone group, ADSC exosome alone group, and HGF-ADSC exosome group, with 6 mice in each group, and treated accordingly. On post injury day (PID) 3, 7, 10, and 14, the wounds were observed and the wound healing rate was calculated; the blood flow intensity of wound base was detected by Doppler flowmeter and the ratio of relative blood flow intensity on PID 10 was calculated. On PID 10, the number of Ki67 positive cells in wounds was detected by immunofluorescence method, and the number of new-vascularity of CD31 positive staining and tubular neovascularization in the wounds was detected by immunohistochemistry method; the protein expressions of protein endothelial nitric oxide synthase (eNOS), phosphatidylinositol 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), protein kinase B (Akt) and phosphorylated Akt (p-Akt) in wounds were detected by Western blotting, and the ratios of p-PI3K to PI3K and p-Akt to Akt were calculated. On PID 14, the defect length and collagen regeneration of wound skin tissue were detected by hematoxylin and eosin staining and Masson staining, respectively, and the collagen volume fraction (CVF) was calculated. The number of samples is 3 in all cases. Data were statistically analyzed with repeated measurement analysis of variance, one-way analysis of variance, and Tukey test. Results: After 7 days of culture, the primary ADSCs were spindle shaped and arranged in vortex shape after dense growth. After 5 days of culture, HGF transfected ADSCs of the third passage carried green fluorescence, and the transfection rate was 85%. The ADSC exosomes and HGF-ADSC exosomes were similar in microscopic morphology, showing vesicular structures with an average particle size of 103 nm and 98 nm respectively, and both were CD9, CD63, and CD81 positive. On PID 3, the wounds of mice in the 4 groups were all red and swollen, with a small amount of exudate. On PID 7, the wounds of HGF-ADSC exosome group were gradually reduced, while the wounds of the other three groups were not significantly reduced. On PID 10, the wounds in the 4 groups were all reduced and scabbed. On PID 14, the wounds in HGF-ADSC exosome group were basically healed, while the residual wounds were found in the other three groups. On PID 3, the healing rates of wounds in the four groups were similar (P>0.05); On PID 7 and 10, the wound healing rates in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 13.11, 13.11, 11.89, 12.85, 11.28, and 7.74, respectively, all P<0.01); on PID 14, the wound healing rate in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 15.50, 11.64, and 6.36, respectively, all P<0.01). On PID 3, there was no obvious blood supply in wound base of mice in the 4 groups. On PID 7, microvessels began to form in the wound base of HGF-ADSC exosome group, while the wound base of the other three groups was only congested at the wound edge. On PID 10, microvessel formation in wound base was observed in the other 3 groups except in PBS group, which had no obvious blood supply. On PID 14, the blood flow intensity of wound base in HGF-ADSC exosome group was stronger than that in the other 3 groups, and the distribution was uniform. On PID 10, the ratio of wound base relative blood flow intensity in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 23.73, 19.32, and 9.48, respectively, all P<0.01); The numbers of Ki67-positive cells and new-vascularity of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 19.58, 18.20, 11.04, 20.68, 13.79, and 8.12, respectively, P<0.01). On PID 10, the protein expression level of eNOS of wounds in HGF-ADSC exosome group was higher than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 53.23, 42.54, and 26.54, respectively, all P<0.01); the ratio of p-PI3K to PI3K and the ratio of p-Akt to Akt of wounds in HGF-ADSC exosome group were significantly higher than those in PBS group, HGF alone group, and ADSC exosome alone group, respectively (with q values of 16.11, 11.78, 6.08, 65.54, 31.63, and 37.86, respectively, P<0.01). On PID 14, the length of skin tissue defect in the wounds of HGF-ADSC exosome group was shorter than that in PBS group, HGF alone group, and ADSC exosome alone group (with q values of 20.51, 18.50, and 11.99, respectively, all P<0.01); the CVF of wounds in HGF-ADSC exosome group was significantly higher than that in PBS group, HGF alone group and ADSC exosome alone group (with q values of 31.31, 28.52, and 12.35, respectively, all P<0.01). Conclusions: Human HGF-ADSC exosomes can significantly promote wound healing in diabetic mice by increasing neovascularization in wound tissue, and the mechanism may be related to the increased expression of eNOS in wounds by activating PI3K/Akt signaling pathway.

Association between asymptomatic hyperuricemia and knee osteoarthritis in older outpatients.

OBJECTIVE: To investigate the association between asymptomatic hyperuricemia and knee osteoarthritis in older outpatients in Vietnam. PATIENTS AND METHODS: This cross-sectional study included 257 older outpatients (195 in the knee osteoarthritis group and 62 in the non-knee osteoarthritis group) aged ≥60 years (mean age 73.31 ± 7.96 years) attending rheumatologic and geriatric clinics from November 2020 to May 2021. Data were collected for both groups, including demographics, symptoms and signs of knee osteoarthritis, serum uric acid levels, and knee radiographs. The association between asymptomatic hyperuricemia and knee osteoarthritis was assessed using logistic regression. RESULTS: The mean serum uric acid level among patients with knee osteoarthritis was higher than that among patients without knee osteoarthritis (6.3 ± 1.74 mg/dl vs. 5.71 ± 1.45 mg/dl, p = 0.017). Hyperuricemia was more common among older outpatients with knee osteoarthritis than among those without knee osteoarthritis (39% vs. 19%, p = 0.005). After adjusting for age, sex, body mass index (BMI), and other comorbidities, the association between asymptomatic hyperuricemia and knee osteoarthritis remained significant (odds ratio [OR] 2.61, 95% confidence interval [CI] 1.22-5.60, p = 0.013). Subgroup analyses were performed according to sex and BMI groups. Significant associations between asymptomatic hyperuricemia and knee osteoarthritis were observed among women (p = 0.017) and among individuals who were underweight-normal-weight according to BMI (p = 0.009). CONCLUSIONS: Asymptomatic hyperuricemia is a common comorbidity among older outpatients with knee osteoarthritis. An independent association was identified between asymptomatic hyperuricemia and knee osteoarthritis among older Vietnamese outpatients, although sex and BMI may be confounding factors that impact this association.

[Clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns].

Objective: To explore the clinical effects of free transplantation of expanded thoracodorsal artery perforator flaps in reconstructing cervical cicatrix contracture deformity after burns. Methods: A retrospective observational study was conducted. From May 2018 to April 2021, 11 patients with cervical cicatrix contracture deformity after burns who met the inclusion criteria were admitted to the First Affiliated Hospital of Air Force Medical University, including 3 males and 8 females, aged 5 to 46 years, with a course of cervical cicatrix contracture deformity of 5 months to 8 years. The degree of cervical cicatrix contracture deformity was degree Ⅰ in one patient, degree Ⅱ in nine patients, and degree Ⅲ in one patient. In the first stage, according to the sizes of neck scars, one rectangular skin and soft tissue expander (hereinafter referred to as expander) with rated capacity of 200 to 600 mL was placed in the back. The expansion time was 4 to 12 months with the total normal saline injection volume being 3.0 to 3.5 times of the rated capacity of expander. In the second stage, free expanded thoracodorsal artery perforator flaps with areas of 10 cm×7 cm to 24 cm×13 cm were cut out to repair the wounds with areas of 9 cm×6 cm to 23 cm×12 cm which was formed after cervical cicatectomy. The main trunk of thoracodorsal artery and vein were selected for end-to-end anastomosis with facial artery and vein, and the donor sites were directly closed. The survival of flaps and healing of flap donor sites were observed on the 14th day post surgery. The appearances and cicatrix contracture deformity of the flaps, recovery of cervical function, and scar hyperplasia of donor sites were followed up. Results: On the 14th day post surgery, the flaps of ten patients survived, while ecchymosis and epidermal necrosis occurred in the center of flap of one patient and healed 2 weeks after dressing change. On the 14th day post surgery, the flap donor sites of 11 patients all healed well. During the follow-up of 6-12 months post surgery, the flaps of ten patients were similar to the skin around the recipient site in texture and color, while the flap of one patient was slightly swollen. All of the 11 patients had good recovery of cervical function and no obvious scar hyperplasia nor contracture in the flaps or at the donor sites. Conclusions: Application of expanded thoracodorsal artery perforator flaps can restore the appearance and function of the neck, and cause little damage to the donor site in reconstructing the cervical cicatrix contracture deformity after burns, which is worthy of clinical reference and application.

[Effects of exosomes from human adipose-derived mesenchymal stem cells on pulmonary vascular endothelial cells injury in septic mice and its mechanism].

Objective: To investigate the effects of exosomes from human adipose-derived mesenchymal stem cells (ADSCs) on pulmonary vascular endothelial cells (PMVECs) injury in septic mice and its mechanism. Methods: The experimental research method was adopted. The primary ADSCs were isolated and cultured from the discarded fresh adipose tissue of 3 patients (female, 10-25 years old), who were admitted to the First Affiliated Hospital of Air Force Medical University undergoing abdominal surgery, and the cell morphology was observed by inverted phase contrast microscope on the 5th day. The expressions of CD29, CD34, CD44, CD45, CD73, and CD90 of ADSCs in the third passage were detected by flow cytometry. The third to the fifth passage of ADSCs were collected, and their exosomes from the cell supernatant were obtained by differential ultracentrifugation, and the shape, particle size, and the protein expressions of CD9, CD63, tumor susceptibility gene 101 (TSG101), and ß-actin of exosomes were detected, respectively, by transmission electron microscopy, nano-particle tracking analysis and Western blotting. Twenty-four adult male BALB/c mice were adopted and were divided into normal control group, caecal ligation perforation (CLP) alone group, and CLP+ADSC-exosome group with each group of 8 according to random number table (the same grouping method below) and were treated accordingly. At 24 h after operation, tumor necrosis factor (TNF-α) and interleukin 1ß (IL-1ß) levels of mice serum were detected by enzyme-linked immunosorbent assay, and lung tissue morphology of mice was detected by hematoxylin-eosin and myeloperoxidase staining, and the expression of 8-hydroxy-deoxyguanosine (8-OHdG) of mouse lung cells was detected by immunofluorescence method. Primary PMVECs were obtained from 1-month-old C57 mice regardless gender by tissue block method. The expression of CD31 of PMVECs was detected by immunofluorescence and flow cytometry. The third passage of PMVECs was co-cultured with ADSCs derived exosomes for 12 h, and the phagocytosis of exosomes by PMVECs was detected by PKH26 kit. The third passage of PMVECs were adopted and were divided into blank control group, macrophage supernatant alone group, and macrophage supernatant+ADSC-exosome group, with 3 wells in each group, which were treated accordingly. After 24 h, the content of reactive oxygen species in cells was detected by flow cytometry, the expression of 8-OHdG in cells was detected by immunofluorescence, and Transwell assay was used to determine the permeability of cell monolayer. The number of samples in above were all 3. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: The primary ADSCs were isolated and cultured to day 5, growing densely in a spindle shape with a typical swirl-like. The percentages of CD29, CD44, CD73 and CD90 positive cells of ADSCs in the third passage were all >90%, and the percentages of CD34 and CD45 positive cells were <5%. Exosomes derived from ADSCs of the third to fifth passages showed a typical double-cavity disc-like structure with an average particle size of 103 nm, and the protein expressions of CD9, CD63 and TSG101 of exosomes were positive, while the protein expression of ß-actin of exosomes was negative. At 24 h after operation, compared with those in normal control group, both the levels of TNF-α and IL-1ß of mice serum in CLP alone group were significantly increased (with t values of 28.76 and 29.69, respectively, P<0.01); compared with those in CLP alone group, both the content of TNF-α and IL-1ß of mice serum in CLP+ADSC-exosome group was significantly decreased (with t values of 9.90 and 4.76, respectively, P<0.05 or P<0.01). At 24 h after surgery, the pulmonary tissue structure of mice in normal control group was clear and complete without inflammatory cell infiltration; compared with those in normal control group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP alone group were more obvious; compared with those in CLP alone group, the pulmonary tissue edema and inflammatory cell infiltration of mice in CLP+ADSC-exosome group were significantly reduced. At 24 h after operation, endothelial cells in lung tissues of mice in 3 groups showed positive expression of CD31; compared with that in normal control group, the fluorescence intensity of 8-OHdG positive cells of the lung tissues of mice in CLP alone group was significantly increased, and compared with that in CLP alone group, the fluorescence intensity of 8-OHdG positive cells in the lung tissues of mice in CLP+ADSC-exosome group was significantly decreased. The PMVECs in the 3rd passage showed CD31 positive expression by immunofluorescence, and the result of flow cytometry showed that CD31 positive cells accounted for 99.5%. At 12 h after co-culture, ADSC-derived exosomes were successfully phagocytose by PMVECs and entered its cytoplasm. At 12 h after culture of the third passage of PMVECs, compared with that in blank control group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant alone group was significantly increased (t=15.73, P<0.01); compared with that in macrophage supernatant alone group, the fluorescence intensity of reactive oxygen species of PMVECs in macrophage supernatant+ADSC-exosome group was significantly decreased (t=4.72, P<0.01). At 12 h after culture of the third passage of PMVECs, and the 8-OHdG positive fluorescence intensity of PMVECs in macrophage supernatant alone group was significantly increased; and compared with that in blank control group, the 8-OHdG positive fluorescence intensity of PMVECs in macrophage+ADSC-exosome supernatant group was between blank control group and macrophage supernatant alone group. At 12 h after culture of the third passage PMVECs, compared with that in blank control group, the permeability of PMVECs monolayer in macrophage supernatant alone group was significantly increased (t=6.34, P<0.01); compared with that in macrophage supernatant alone group, the permeability of PMVECs monolayer cells in macrophage supernatant+ADSC-exosome group was significantly decreased (t=2.93, P<0.05). Conclusions: Exosomes derived from ADSCs can ameliorate oxidative damage in mouse lung tissue, decrease the level of reactive oxygen species, 8-OHdG expression, and permeability of PMVECs induced by macrophage supernatant.