Development and Comparative Study of a Mouse Model of Airway Inflammation and Remodeling Induced by Exosomes Derived from Bone Marrow Mesenchymal Stem Cells.

We developed a model of inflammation and airway remodeling in C57 mice provoked by exosomes derived from bone marrow mesenchymal stem cells infected by respiratory syncytial virus (RSV). The mean size of control and infected exosomes in vitro were 167.9 and 118.5 nm, respectively. After induction of modeled pathology, the severity of airway inflammation and its remodeling were analyzed by histopathological methods. In addition, the blood levels of inflammatory factors IL-10, IL-17, transforming growth factor-ß (TGF-ß), and TNFα were assayed; in the lung tissues, the expression levels of MMP-2, MMP-9, α-smooth muscle actin (α-SMA), and TGF-ß were measured. In the developed model, the effects of RSV-induced and non-induced exosomes were compared with those of inactivated and non-inactivated RSV. Intranasal administration of RSV-induced exosomes decreased the levels of serum inflammatory factors IL-10 and IL-17 and increased the expression of serum proinflammatory cytokine TNFα. Increased levels of MMP-2, MMP-9, and α-SMA, enhanced expression of TGF-ß in the lung tissue, and pathological staining of the lung tissues indicated infiltration with inflammatory cells and luminal constriction. Thus, RSV-induced exosomes can provoke airway inflammation and remodeling in mice similar to RSV, while non-induced exosomes cannot produce such alterations.

[Prediction of the clinical supply of blood components in Xi'an City from 2023 to 2025].

Objective: To construct a prediction model for the clinical supply of blood components in Xi'an City from 2023 to 2025. Methods: Based on the blood supply data of the Blood Management Information System of Shaanxi Provincial Blood Center from January 2013 to December 2022, a gray prediction model and an exponential curve fitting model were used to construct the prediction model, and the optimal prediction model was determined according to the error parameters of the relevant indicators of the model. The supply of blood components in Xi'an from 2023 to 2025 was predicted. Results: The fitting equations of the exponential curve fitting model to predict the supply of suspended red blood cells, platelets and cryoprecipitate in Xi'an were, x（1）（t+1）=1.16e0.04t，x（1）（t+1）=1.04e0.12t and x（1）（t+1）=1.01e1.10t, respectively. The mean absolute errors (mean relative errors) of the exponential curve fitting model in predicting the supply of suspended red blood cells, platelets and cryoprecipitate in Xi'an were 10 488.7 (0.05%), 2 114.9 (0.08%) and 3 089.6 (0.07%), respectively, which were lower than those of the gray prediction model, about 10 488.7 (3.44%), 2 152.78 (8.20%) and 3 441.35 (7.92%), respectively. The exponential curve fitting model predicted that the clinical supply of blood components in Xi'an would increase year by year from 2023 to 2025, and the clinical supply of suspended red blood cells, platelets, and cryoprecipitate in Xi'an would increase to 409 467 U, 69 818 therapeutic volume and 94 724 U, respectively by 2025. Conclusion: The exponential curve fitting model can make a good prediction of the clinical supply of blood components in Xi'an City.

Crystallization Kinetics of Phosphonium Ionic Liquids: Effect of Cation Alkyl Chain Length and Thermal History.

The effects of alkyl chain length on the crystallization kinetics and ion mobility of tetraalkylphosphonium, [P666,n][TFSI], (n = 2, 6, 8, and 12) ionic liquids were studied by differential scanning calorimetry (DSC) and broadband dielectric spectroscopy (BDS) over a wide temperature range. The liquid-glass transition temperature (Tg) and ion dynamics examined over a broad T range were almost insensitive to structural modifications of the phosphonium cation. In contrast, the crystallization kinetics were strongly affected by the length of the fourth alkyl chain. Furthermore, the thermal history of the sample (cold vs melt crystallization) significantly impacted the crystallization rate. It has been found that the nature of crystallization phenomena is the same across the homologous series, while the kinetic aspect differs. Finally, electric conductivity in supercooled liquid and crystalline solid phases was measured for all samples, revealing significant ionic conductivity, largely independent of the cation structure.

Endurance Training Inhibits the JAK2/STAT3 Pathway to Alleviate Sarcopenia.

Aging leads to a decrease in muscle function, mass, and strength in skeletal muscle of animals and humans. The transcriptome identified activation of the JAK/STAT pathway, a pathway that is associated with skeletal muscle atrophy, and endurance training has a significant effect on improving sarcopenia; however, the exact mechanism still requires further study. We investigated the effect of endurance training on sarcopenia. Six-month-old male SAMR1 mice were used as a young control group (group C), and the same month-old male SAMP8 mice were divided into an exercise group (group E) and a model group (group M). A 3-month running exercise intervention was performed on group E, and the other two groups were kept normally. Aging caused significant signs of sarcopenia in the SAMP8 mice, and endurance training effectively improved muscle function, muscle mass, and muscle strength in the SAMP8 mice. The expression of JAK2/STAT3 pathway factor was decreased in group E compared with group M, and the expression of SOCS3, the target gene of STAT3, and NR1D1, an atrophy-related factor, was significantly increased. Endurance training significantly improved the phenotypes associated with sarcopenia, and the JAK2/STAT3 pathway is a possible mechanism for the improvement of sarcopenia by endurance training, while NR1D1 may be its potential target. Keywords: Sarcopenia, Endurance training, Janus kinase 2/signal transducer and activator of transcription 3 (JAK2/STAT3), Nuclear receptor subfamily 1, group D member 1 (Nr1d1).

Inflection Point in Pressure Dependence of Ionic Conductivity as a Fingerprint of Local Structure Formation.

In this study, we employed dielectric spectroscopy to investigate the effect of temperature and pressure on the ion dynamics of phosphonium ionic liquids (ILs) differing by the length of an alkyl chain, [P666,n][TFSI] (n = 2, 6, 8, 12). We found that both temperature and pressure dependence of dc-conductivity (σdc) determined for all examined ILs herein exhibit unique characteristics, unusual for aprotic ILs. Two regions differing by ion self-organization have been identified from the derivative analysis of σdc(T-1) data. On the other hand, isothermal measurements performed at elevated pressure revealed a unique concave-convex character of σdc(P) dependences, resulting in a clear minimum in the pressure behavior of activation volume. Such an inflection point characterizing the pressure dependence of σdc in [P666,n][TFSI] ILs can be considered an inherent feature of ion dynamics governed by structural self-assembly. Our results offer a unique perspective to link the ion mobility at various T-P conditions to the nanostructural organization of ionic systems.

Non-Isochronal Behavior of Charge Transport at Liquid-Liquid and Liquid-Glass Transition in Aprotic Ionic Liquids.

A reversible, first-order transition separating two liquid phases of a single-component material is a fascinating yet poorly understood phenomenon. Here, we investigate the liquid-liquid transition (LLT) ability of two tetraalkylphosphonium ionic liquids (ILs), [P666,14]Cl and [P666,14][1,2,4-triazolide], using differential scanning calorimetry and dielectric spectroscopy. The latter technique also allowed us to study the LLT at elevated pressure. We found that cooling below 205 K transforms [P666,14]Cl and [P666,14][Trz] from one liquid state (liquid 1) to another (the self-assembled liquid 2), while the latter facilitates the charge transport decoupled from structural dynamics. In contrast to temperature, pressure was found to play an essential role in the self-organization of a liquid 2 phase, resulting in different time scales of charge transport for rapidly and slowly compressed samples. Furthermore, τσ(PLL) was found to be much shorter than τσ(TLL, P=atm), which constitutes the first example of non-isochronal behavior of charge transport at LLT. In turn, dielectric studies through the liquid-glass transition revealed the non-monotonic behavior of τσ at elevated pressure for [P666,14]Cl, while for [P666,14][Trz] τσ(Pg) was almost constant. These results highlight the diversity of liquid-liquid transition features within the class of phosphonium ionic liquids.

Sudomotor dysfunction is associated with impaired left ventricular diastolic function in persons with type 2 diabetes: a cross-sectional study.

BACKGROUND: The incidence of preserved ejection fraction heart failure has significantly increased in persons with type 2 diabetes mellitus (T2DM). Left ventricular (LV) diastolic dysfunction is an early and important manifestation of preserved ejection fraction heart failure. The onset of heart failure in persons with diabetes is associated with diabetic neuropathy. However, the relationship among sudomotor function, which is an early manifestation of small fiber neuropathy, and LV diastolic function remains unclear. This study aimed to explore the association between sudomotor function and LV diastolic function in persons with T2DM. METHODS: In total, 699 persons with T2DM were enrolled and divided into three groups according to electrochemical skin conductance (ESC) assessed using the SUDOSCAN device: "no dysfunction" group (NSF), "moderate dysfunction" group (MDF), and "severe dysfunction" group (SDF). LV diastolic function was assessed using Doppler echocardiography. To evaluate the relationship between ESC and echocardiographic parameters, Pearson's correlation analysis was performed. Additionally, logistic regression analysis was used to determine the association between LV diastolic function and ESC. A receiver operating characteristic (ROC) curve was constructed to evaluate the performance of sudomotor function indicators in detecting impaired cardiac diastolic function. RESULTS: There were 301 persons (43.06%) in the NSF group, 232 (33.19%) in the MDF group, and 166 (23.75%) in the SDF group. Compared to the NSF group, the MDF and SDF groups had higher A and E/e' and lower e' values (all p < 0.05). Pearson's correlation analysis showed that A and E/e' were negatively associated with foot ESC (FESC) and hand ESC (HESC), whereas e' was positively associated with FESC and HESC (all p < 0.05). After adjusting for confounding factors, binary logistic regression analysis showed that ESC was independently associated with impaired LV diastolic function (p = 0.003). The area under the ROC curve values for FESC and HESC were 0.621 and 0.635, respectively (both p < 0.05). CONCLUSIONS: Deteriorating sudomotor function was associated with reduced diastolic function indicators. ESC can be used as a biomarker for detecting LV diastolic impairment.

[Pelvic exenteration for late complications of radiation-induced pelvic injury: a preliminary study].

Objective: To investigate the safety and efficacy of total pelvic exenteration (TPE) for treating late complications of radiation-induced pelvic injury. Methods: This was a descriptive case series study. The inclusion criteria were as follows: (1) confirmed radiation-induced pelvic injury after radiotherapy for pelvic malignancies; (2) late complications of radiation-induced pelvic injury, such as bleeding, perforation, fistula, and obstruction, involving multiple pelvic organs; (3) TPE recommended by a multidisciplinary team; (4) patient in good preoperative condition and considered fit enough to tolerate TPE; and (5) patient extremely willing to undergo the procedure and accept the associated risks. The exclusion criteria were as follows: (1) preoperative or intraoperative diagnosis of tumor recurrence or metastasis; (2) had only undergone diversion or bypass surgery after laparoscopic exploration; and (3) incomplete medical records. Clinical and follow-up data of patients who had undergone TPE for late complications of radiation-induced pelvic injury between March 2020 and September 2022 at the Sixth Affiliated Hospital of Sun Yat-sen University were analyzed. Perioperative recovery, postoperative complications, perioperative deaths, and quality of life 1 year postoperatively were recorded. Results: The study cohort comprised 14 women, nine of whom had recto-vagino-vesical fistulas, two vesicovaginal fistulas, one ileo-vesical fistula and rectal necrosis, one ileo-vesical and rectovaginal fistulas, and one rectal ulcer and bilateral ureteral stenosis. The mean duration of surgery was 592.1±167.6 minutes and the median blood loss 550 (100-6000) mL. Ten patients underwent intestinal reconstruction, and four the Hartmann procedure. Ten patients underwent urinary reconstruction using Bricker's procedure and 7 underwent pelvic floor reconstruction. The mean postoperative hospital stay was 23.6±14.9 days. Seven patients (7/14) had serious postoperative complications (Clavien-Dindo IIIa to IVb), including surgical site infections in eight, abdominopelvic abscesses in five, pulmonary infections in five, intestinal obstruction in four, and urinary leakage in two. Empty pelvis syndrome (EPS) was diagnosed in five patients, none of whom had undergone pelvic floor reconstruction. Five of the seven patients who had not undergone pelvic floor reconstruction developed EPS, compared with none of those who had undergone pelvic floor reconstruction. One patient with EPS underwent reoperation because of a pelvic abscess, pelvic hemorrhage, and intestinal obstruction. There were no perioperative deaths. During 18.9±10.1 months of follow-up, three patients died, two of renal failure, which was a preoperative comorbidity, and one of COVID-19. The remaining patients had gradual and significant relief of symptoms during follow-up. QLQ-C30 assessment of postoperative quality of life showed gradual improvement in all functional domains and general health at 1, 3, and 6 months postoperatively (all P<0.05). Conclusions: TPE is a feasible procedure for treating late complications of radiation-induced pelvic injury combined with complex pelvic fistulas. TPE is effective in alleviating symptoms and improving quality of life. However, the indications for this procedure should be strictly controlled and the surgery carried out only by experienced surgeons.

[Observational study on perioperative outcomes of pelvic exenteration].

Objective: To investigate the surgical indications and perioperative clinical outcomes of pelvic exenteration (PE) for locally advanced, recurrent pelvic malignancies and complex pelvic fistulas. Methods: This was a descriptive study.The indications for performing PE were: (1) locally advanced, recurrent pelvic malignancy or complex pelvic fistula diagnosed preoperatively by imaging and pathological examination of a biopsy; (2)preoperative agreement by a multi-disciplinary team that non-surgical and conventional surgical treatment had failed and PE was required; and (3) findings on intraoperative exploration confirming this conclusion.Contraindications to this surgical procedure comprised cardiac and respiratory dysfunction, poor nutritional status,and mental state too poor to tolerate the procedure.Clinical data of 141 patients who met the above criteria, had undergone PE in the Sixth Affiliated Hospital of Sun Yat-sen University from January 2018 to September 2022, had complete perioperative clinical data, and had given written informed consent to the procedure were collected,and the operation,relevant perioperative variables, postoperative pathological findings (curative resection), and early postoperative complications were analyzed. Results: Of the 141 included patients, 43 (30.5%) had primary malignancies, 61 (43.3%) recurrent malignancies, 28 (19.9%) complex fistulas after radical resection of malignancies,and nine (6.4%)complex fistulas caused by benign disease. There were 79 cases (56.0%) of gastrointestinal tumors, 30 cases (21.3%) of reproductive tumors, 16 cases (11.3%) of urinary tumors, and 7 cases (5.0%) of other tumors such mesenchymal tissue tumors. Among the 104 patients with primary and recurrent malignancies, 15 patients with severe complications of pelvic perineum of advanced tumors were planned to undergo palliative PE surgery for symptom relief after preoperative assessment of multidisciplinary team; the other 89 patients were evaluated for radical PE surgery. All surgeries were successfully completed. Total PE was performed on 73 patients (51.8%),anterior PE on 22 (15.6%),and posterior PE in 46 (32.6%). The median operative time was 576 (453,679) minutes, median intraoperative blood loss 500 (200, 1 200) ml, and median hospital stay 17 (13.0,30.5)days.There were no intraoperative deaths. Of the 89 patients evaluated for radical PE surgery, the radical R0 resection was achieved in 64 (71.9%) of them, R1 resection in 23 (25.8%), and R2 resection in two (2.2%). One or more postoperative complications occurred in 85 cases (60.3%), 32 (22.7%)of which were Clavien-Dindo grade III and above.One patient (0.7%)died during the perioperative period. Conclusion: PE is a valid option for treating locally advanced or recurrent pelvic malignancies and complex pelvic fistulas.

Cardiovascular magnetic resonance myocardial feature tracking for the determination of left atrial strain in hypertensive left ventricular hypertrophy and hypertrophic cardiomyopathy.

AIM: To measure the left atrial (LA) function in patients with hypertrophic cardiomyopathy (HCM; with [OHCM] and without obstruction [NOHCM]) and hypertension-related left ventricular hypertrophy (H-LVH) using cardiovascular magnetic resonance imaging feature tracking (CMR-FT). MATERIALS AND METHODS: Patients who met the criteria for HCM (n=68), H-LVH (n=46), and 30 healthy controls participated. Left atrial strain was analysed using CMR-FT in cine images with two and four chambers. RESULTS: The strain rate and LA strain measurements showed that patients with HCM, and H-LVH had impaired conduit and reservoir functions (versus controls). These capacities were more severely impaired in OHCM than those seen in NOHCM and H-LVH. The LA volume parameters (LAVIpac, LAVImin and LAVImax) from the OHCM group were higher than both the NOHCM and H-LVH groups (all p<0.05). There were differences between the OHCM and H-LVH groups in terms of the parameters for LA reservoir function (εs), booster pump function (SRa), and conduit function (SRe, LA passive EF, εe; p<0.05). The strongest correlations included the associations between LA total EF and εs, εe and LA passive EF, and SRe and LA passive EF. CONCLUSION: CMR-FT can reliably identify LA dysfunction and deformation in the early stages of HCM and H-LVH.

Effect of bulky anions on the liquid-liquid phase transition in phosphonium ionic liquids: Ambient and high-pressure dielectric studies.

Although the first-order liquid-liquid phase transition (LLT) has been reported to exist in various systems (i.e., phosphorus, silicon, water, triphenyl phosphite, etc.), it is still one of the most challenging problems in the field of physical science. Recently, we found that this phenomenon occurs in the family of trihexyl(tetradecyl)phosphonium [P666,14]+ based ionic liquids (ILs) with different anions (Wojnarowska et al in Nat Commun 13:1342, 2022). To understand the molecular structure-property relationships governing LLT, herein, we examine ion dynamics of two other quaternary phosphonium ILs containing long alkyl chains in cation and anion. We found that IL with the anion containing branched -O-(CH2)5-CH3 side chains does not reveal any signs of LLT, while IL with shorter alkyl chains in the anion brings a hidden LLT, i.e., it overlaps with the liquid-glass transition. Ambient pressure dielectric and viscosity measurements revealed a peculiar behavior of ion dynamics near Tg for IL with hidden LLT. Moreover, high-pressure studies have shown that IL with hidden LLT has relatively strong pressure sensitivity compared to the one without first-order phase transition. At the same time, the former exposes the inflection point indicating the concave-convex character of logτσ(P) dependences.

The effect of curcumin on on intravitreal proinflammatory cytokines, oxidative stress markers, and vascular endothelial growth factor in an experimental model of diabetic retinopathy.

The prevalence of diabetic retinopathy (DR) is high among individuals with diabetes. Curcumin (CUR) has been suggested as a possible treatment for this condition. This study aimed to investigate the impact of CUR on pro-inflammatory cytokines, oxidative stress markers, and vascular endothelial growth factor (VEGF) in an experimental model of DR. The study used Spontaneously Diabetic Torii (SDT) rats and divided them into groups to receive various CUR doses (10, 50, 100 mg/kg/day) or distilled water for four weeks. Non-diabetic Sprague-Dawley (SD) rats were used as a control group. Pro-inflammatory cytokines (interleukin (IL)-1, IL-6, tumor necrosis factor alpha (TNF-α), interferon gamma (IFN-γ)) (by ELISA), oxidative stress markers (superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GPX), catalase (CAT)), and VEGF expression (by RT-PCR) and content (by Western-blot and immunostaining) were assessed as outcome measures. The study found that diabetic rats who received varying doses of CUR showed a decrease in pro-inflammatory cytokines (TNF-α, IFN-γ, IL-1), oxidative stress markers (SOD, MDA, GPX, CAT), and VEGF expression and content in the vitreous. The decrease in these markers was dose-dependent and significantly different from diabetic rats who did not receive CUR (p<0.01). However, there was no significant difference in the vitreous level of IL-6 between the groups (p=0.35). The study concluded that CUR has the potential to alleviate inflammation and oxidative stress induced by diabetes in the vitreous microenvironment of rats. CUR also reduced the increase in VEGF levels in the vitreous of diabetic rats. These findings suggest that CUR could be a viable therapeutic option for the treatment of DR.

[Research advances on the construction of an ideal scar model in vitro based on innovative tissue engineering technology].

The scar brings a huge economic burden and creates a serious psychological shadow for patients. Although the current methods for scar treatment tend to be diversified, the treatment method that can truly achieve the goal of "perfect healing" or "scarless healing" after human skin injury is quite scarce. With the wide application of tissue engineering technologies in medicine research, technologies such as three-dimensional bioprinting, organoid culture, and organ chip technologies are constantly emerging. Disease models in vitro based on these innovative technologies showed more advantages than traditional animal disease models. The article introduces the current hotspot technologies in skin tissue engineering such as organoid culture, three-dimensional bioprinting, and organ chip technologies, focuses on summarizing the three key elements to be mastered for constructing an ideal scar model in vitro, and puts forward the future prospect of constructing an ideal scar model in vitro based on our research team's long-term experience in skin tissue repair and regeneration research.

SOX2 como posible biomarcador pronóstico y diana molecular en el cáncer de pulmón: metaanálisis.

OBJECTIVE: To determine the association of SOX2 with the prognosis in lung cancer, studies providing survival information were selected based on multivariate Cox regression analysis. MATERIAL AND METHODS: PubMed, Embase, and Web of Science databases were searched to identify eligible studies before June 19, 2021. The hazard ratios (HR) with 95% confidence intervals (CI) were calculated to assess the prognostic impact of SOX2 based on multivariate Cox regression analysis. Publication bias was used to assess the risk of bias. Functional analysis of SOX2 was also conducted. RESULTS: 13 studies with a total of 2008 patients with lung cancer were included. SOX2 expression was not correlated with overall survival in lung cancer (10 studies with 1591 cases). Between-study heterogeneity was noted (I2=85.6%, p<0.0001). Subgroup analysis suggested that no correlation was found between SOX2 expression and overall survival in non-small cell lung cancer (NSCLC: eight studies with 1319 cases) and small-cell lung cancer (SCLC: two studies with 272 cases). SOX2 expression was significantly associated with worse time-to-progression (two studies with 104 cases: HR=3.50, 95% CI=1.34-9.15) and recurrence-free survival (two studies with 335 cases: HR=1.45, 95% CI=1.12-1.87) in NSCLC. Function analysis demonstrated that SOX2 was involved in DNA repair, cell cycle, regulation of stem cell population maintenance, and Hippo signaling pathway. CONCLUSION: SOX2 may be an independent prognostic factor in time-to-progression and recurrence-free survival and may become a promising therapeutic target. More studies are essential to further our findings.

[Effects of in situ cross-linked graphene oxide-containing gelatin methacrylate anhydride hydrogel on wound vascularization of full-thickness skin defect in mice].

Objective: To prepare graphene oxide (GO)-containing gelatin methacrylate anhydride (GelMA) hydrogel and to investigate the effects of in situ photopolymerized GO-GelMA composite hydrogel in wound vascularization of full-thickness skin defect in mice. Methods: The experimental study method was used. The 50 µL of 0.2 mg/mL GO solution was evenly applied onto the conductive gel, and the structure and size of GO were observed under field emission scanning electron microscope after drying. Human skin fibroblasts (HSFs) were divided into 0 µg/mL GO (without GO solution, the same as below) group, 0.1 µg/mL GO group, 1.0 µg/mL GO group, 5.0 µg/mL GO group, and 10.0 µg/mL GO group treated with GO of the corresponding final mass concentration, and the absorbance value was detected using a microplate analyzer after 48 h of culture to reflect the proliferation activity of cells (n=6). HSFs and human umbilical vein vascular endothelial cells (HUVECs) were divided into 0 µg/mL GO group, 0.1 µg/mL GO group, 1.0 µg/mL GO group, and 5.0 µg/mL GO group treated with GO of the corresponding final mass concentration, and the migration rates of HSFs at 24 and 36 h after scratching (n=5) and HUVECs at 12 h after scratching (n=3) were detected by scratch test, and the level of vascular endothelial growth factor (VEGF) secreted by HSFs after 4, 6, and 8 h of culture was detected by enzyme-linked immunosorbent assay method (n=3). The prepared GO-GelMA composite hydrogels containing GO of the corresponding final mass concentration were set as 0 µg/mL GO composite hydrogel group, 0.1 µg/mL GO composite hydrogel group, 1.0 µg/mL GO composite hydrogel group, and 5.0 µg/mL GO composite hydrogel group to observe their properties before and after cross-linking, and to detect the release of GO after soaking with phosphate buffer solution for 3 and 7 d (n=3). The full-thickness skin defect wounds were made on the back of 16 6-week-old female C57BL/6 mice. The mice treated with in situ cross-linked GO-GelMA composite hydrogel containing GO of the corresponding final mass concentration were divided into 0 µg/mL GO composite hydrogel group, 0.1 µg/mL GO composite hydrogel group, 1.0 µg/mL GO composite hydrogel group, and 5.0 µg/mL GO composite hydrogel group according to the random number table, with 4 mice in each group. The general condition of wound was observed and the wound healing rate was calculated on 3, 7, and 14 d of treatment, the wound blood perfusion was detected by laser Doppler flowmetry on 3, 7, and 14 d of treatment and the mean perfusion unit (MPU) ratio was calculated, and the wound vascularization on 7 d of treatment was observed after hematoxylin-eosin staining and the vascular density was calculated (n=3). The wound tissue of mice in 0 µg/mL GO composite hydrogel group and 0.1 µg/mL GO composite hydrogel group on 7 d of treatment was collected to observe the relationship between the distribution of GO and neovascularization by hematoxylin-eosin staining (n=3) and the expression of VEGF by immunohistochemical staining. Data were statistically analyzed with analysis of variance for repeated measurement, one-way analysis of variance, and Tukey's method. Results: GO had a multilayered lamellar structure with the width of about 20 µm and the length of about 50 µm. The absorbance value of HSFs in 10.0 µg/mL GO group was significantly lower than that in 0 µg/mL GO group after 48 h of culture (q=7.64, P<0.01). At 24 h after scratching, the migration rates of HSFs were similar in the four groups (P>0.05); at 36 h after scratching, the migration rate of HSFs in 0.1 µg/mL GO group was significantly higher than that in 0 µg/mL GO group, 1.0 µg/mL GO group, and 5.0 µg/mL GO group (with q values of 7.48, 10.81, and 10.20, respectively, P<0.01). At 12 h after scratching, the migration rate of HUVECs in 0.1 µg/mL GO group was significantly higher than that in 0 µg/mL GO group, 1.0 µg/mL GO group, and 5.0 µg/mL GO group (with q values of 7.11, 8.99, and 14.92, respectively, P<0.01), and the migration rate of HUVECs in 5.0 µg/mL GO group was significantly lower than that in 0 µg/mL GO group and 1.0 µg/mL GO group (with q values of 7.81 and 5.33, respectively, P<0.05 or P<0.01 ). At 4 and 6 h of culture, the VEGF expressions of HSFs in the four groups were similar (P>0.05); at 8 h of culture, the VEGF expression of HSFs in 0.1 µg/mL GO group was significantly higher than that in 0 µg/mL GO group and 5.0 µg/mL GO group (with q values of 4.75 and 4.48, respectively, P<0.05). The GO-GelMA composite hydrogels in the four groups were all red liquid before cross-linking, which turned to light yellow gel after cross-linking, with no significant difference in fluidity. The GO in the GO-GelMA composite hydrogel of 0 µg/mL GO composite hydrogel group had no release of GO at all time points; the GO in the GO-GelMA composite hydrogels of the other 3 groups was partially released on 3 d of soaking, and all the GO was released on 7 d of soaking. From 3 to 14 d of treatment, the wounds of mice in the 4 groups were covered with hydrogel dressings, kept moist, and gradually healed. On 3, 7, and 14 d of treatment, the wound healing rates of mice in the four groups were similar (P>0.05). On 3 d of treatment, the MPU ratio of wound of mice in 0.1 µg/mL GO composite hydrogel group was significantly higher than that in 0 µg/mL GO composite hydrogel group, 1.0 µg/mL GO composite hydrogel group, and 5.0 µg/mL GO composite hydrogel group (with q values of 10.70, 11.83, and 10.65, respectively, P<0.05 or P<0.01). On 7 and 14 d of treatment, the MPU ratios of wound of mice in the four groups were similar (P>0.05). The MPU ratio of wound of mice in 0.1 µg/mL GO composite hydrogel group on 7 d of treatment was significantly lower than that on 3 d of treatment (q=14.38, P<0.05), and that on 14 d of treatment was significantly lower than that on 7 d of treatment (q=27.78, P<0.01). On 7 d of treatment, the neovascular density of wound of mice on 7 d of treatment was 120.7±4.1 per 200 times of visual field, which was significantly higher than 61.7±1.3, 77.7±10.2, and 99.0±7.9 per 200 times of visual field in 0 µg/mL GO composite hydrogel group, 1.0 µg/mL GO composite hydrogel group, and 5.0 µg/mL GO composite hydrogel group (with q values of 12.88, 7.79, and 6.70, respectively, P<0.01), and the neovascular density of wound of mice in 1.0 µg/mL GO composite hydrogel group and 5.0 µg/mL GO composite hydrogel group was significantly higher than that in 0 µg/mL GO composite hydrogel group (with q values of 5.10 and 6.19, respectively, P<0.05). On 7 d of treatment, cluster of new blood vessels in wound of mice in 0.1 µg/mL GO composite hydrogel group was significantly more than that in 0 µg/mL GO composite hydrogel group, and the new blood vessels were clustered near the GO; a large amount of VEGF was expressed in wound of mice in 0.1 µg/mL GO composite hydrogel group in the distribution area of GO and new blood vessels. Conclusions: GO with mass concentration lower than 10.0 µg/mL had no adverse effect on proliferation activity of HSFs, and GO of 0.1 µg/mL can promote the migration of HSFs and HUVECs, and can promote the secretion of VEGF in HSFs. In situ photopolymerized of GO-GelMA composite hydrogel dressing can promote the wound neovascularization of full-thickness skin defect in mice and increase wound blood perfusion in the early stage, with GO showing an enrichment effect on angiogenesis, and the mechanism may be related to the role of GO in promoting the secretion of VEGF by wound cells.

[Curcumin alleviates the manganese-induced neurotoxicity by promoting autophagy in rat models of manganism].

OBJECTIVE: To investigate the protective effects of curcumin(CUR) and its mechanism on a rat model of neurotoxicity induced by manganese chloride (MnCl2), which mimics mangnism. METHODS: Sixty male SD rats were randomly divided into 5 groups, with 12 rats in each group. Control group received 0.9% saline solution intraperitoneally (ip) plus double distilled water (dd) H2O intragastrically (ig), MnCl2 group received 15 mg/kg MnCl2(Mn2+ 6.48 mg/kg) intraperitoneally plus dd H2O intragastrically, CUR group received 0.9% saline solution intraperitoneally plus 300 mg/kg CUR intragastrically, MnCl2+ CUR1 group received 15 mg/kg MnCl2 intraperitoneally plus 100 mg/kg curcumin intragastrically, MnCl2+ CUR2 group received 15 mg/kg MnCl2 intraperitoneally plus 300 mg/kg CUR intragastrically, 5 days/week, 4 weeks. Open-field and rotarod tests were used to detect animals' exploratory behavior, anxiety, depression, movement and balance ability. Morris water maze (MWM) experiment was used to detect animals' learning and memory ability. ICP-MS was used to investigate the Mn contents in striata. The rats per group were perfused in situ, their brains striata were removed by brains model and fixed for transmission electron microscope (TEM), histopathological and immunohistochemistry (ICH) analyses. The other 6 rats per group were sacrificed. Their brains striata were removed and protein expression levels of transcription factor EB (TFEB), mammalian target of rapamycin (mTOR), p-mTOR, Beclin, P62, microtubule-associated protein light chain-3 (LC3) were detected by Western blotting. Terminal deoxynucleotidyl transterase-mediated dUTP nick end labeling (TUNEL) staining was used to determine neurocyte apoptosis of rat striatum. RESULTS: After exposure to MnCl2 for four weeks, MnCl2-treated rats showed depressive-like behavior in open-field test, the impairments of movement coordination and balance in rotarod test and the diminishment of spatial learning and memory in MWM (P < 0.05). The striatal TH+ neurocyte significantly decreased, eosinophilic cells, aggregative α-Syn level and TUNEL-positive neurocyte significantly increased in the striatum of MnCl2 group compared with control group (P < 0.05). Chromatin condensation, mitochondria tumefaction and autophagosomes were observed in rat striatal neurocytes of MnCl2 group by TEM. TFEB nuclear translocation and autophagy occurred in the striatum of MnCl2 group. Further, the depressive behavior, movement and balance ability, spatial learning and memory ability of MnCl2+ CUR2 group were significantly improved compared with MnCl2 group (P < 0.05). TH+ neurocyte significantly increased, the eosinophilic cells, aggregative α-Syn level significantly decreased in the striatum of MnCl2+ CUR2 group compared with MnCl2 group. Further, compared with MnCl2 group, chromatin condensation, mitochondria tumefaction was alleviated and autophagosomes increased, TFEB-nuclear translocation, autophagy was enhanced and TUNEL-positive neurocyte reduced significantly in the striatum of MnCl2+ CUR2 group (P < 0.05). CONCLUSION: Curcumin alleviated the MnCl2-induced neurotoxicity and α-Syn aggregation probably by promoting TFEB nuclear translocation and enhancing autophagy.

Hydrogen solution in high-entropy alloys.

High-entropy alloys (HEAs) have been reported to have superior ability in hydrogen (H) storage and strong resistance to H embrittlement. These exceptional properties are directly related to the H solution in the HEAs. However, the diversity of atomic environments in the HEAs complicate the calculation of the H solution energy. With regard to this, we clarified an origin causing the variety of solution energy from the viewpoint of chemical and elastic interactions of H with the host atoms. Combining the semi-empirical atom potential and first-principles calculations regarding H in FeCrCoNi, NbMoTaW, and FeCuCrMnMo, we found that the elastic interaction presents a visibly linear relationship with the volume expansion caused by H insertion. By contrast, the chemical interaction shows a non-linear relationship with the volume of the interstitial polyhedron. A universal model was then established to generalize the solution energy of H. This model can expeditiously assess the H distribution and provide insight into evolution of the microstructure in HEAs.

[Effects and mechanism of age on the stiffness and the fibrotic phenotype of fibroblasts of human hypertrophic scar].

Objective: To explore the effects and potential molecular mechanism of age on the stiffness and the fibrotic phenotype of fibroblasts (Fbs) of human hypertrophic scar. Methods: The experimental research method was used. From January to June 2020, the surgically removed hypertrophic scar tissue of 10 scar patients (4 males and 6 females) and residual full-thickness normal skin tissue of 10 cases (5 males and 5 females, aged 7-41 years) were collected after operation in Department of Burns and Plastic Surgery of the Fourth Medical Center of the PLA General Hospital. The hypertrophic scar tissue of 6 patients aged (10.7±1.6) years was included into the young group and the hypertrophic scar tissue of 4 patients aged (40.0±2.2) years was included into the elderly group according to the age of patients. For the normal skin tissue and scar tissue in the two groups, hematoxylin eosin (HE) staining was performed to observe the tissue morphology, Masson staining was performed to observe the morphology and arrangement of collagen and quantify the content of collagen, and scanning electron microscope was used to observe the microscopic difference of dermal collagen fibers after the samples were freeze-dried and metal coated. The stiffness of scar tissue in the two groups was measured by atomic force microscope under the liquid phase. The scar tissue in the two groups was collected and the Fbs were isolated and cultured. The morphological differences of the Fbs were observed under the inverted phase contrast microscope, and the protein expression of paxillin was detected with cellular immunofluorescence to reflect the morphology of the Fbs. Cellular immunofluorescence was used to detect the expressions of pro-fibrosis protein α-smooth actin (α-SMA), transforming growth factor-ß1 (TGF-ß1), and type Ⅰ collagen, mechanotransduction-related protein Yes-associated protein (YAP), and the proliferation-related protein Ki67. Real-time fluorescent quantitative reverse transcription polymerase chain reaction was used to detect the mRNA expressions of pro-fibrosis genes of TGF-ß1, α-SMA, and type Ⅰ collagen, fibrosis inhibiting gene of TGF-ß3, and mechanotransduction-related genes of Rho-associated protein 1 (ROCK1) and YAP. Data were statistically analyzed with one-way analysis of variance and least significant difference t test. Results: HE staining showed that the epidermal layer of normal skin was uneven, and blood vessels and sweat glands could be seen in the dermal layer; the epidermal layer of the scar tissue in the two groups was relatively flat, and blood vessels and sweat glands were rare. Masson staining and scanning electron microscopy showed that the collagen fibers in normal skin arranged loosely and disorderly, while the collagen fibers in scar tissue of the two groups arranged densely and orderly, and the collagen fibers in scar tissue of the young group were denser than those of the elderly group. The collagen content in scar tissue of the young group and the elderly group was significantly higher than that of the normal skin tissue (t=8.02, 3.15, P<0.05 or P<0.01), and the collagen content in scar tissue of the elderly group was significantly lower than that of the young group (t=4.84, P<0.05). The dermal stiffness of scar tissue in the elderly group was (50.3±1.1) kPa, significantly higher than (35.2±0.8) kPa in the young group (t=11.43, P<0.05). There were no obvious differences in the morphology of scar Fbs in the two groups observed under inverted phase contrast microscope and by cellular immunofluorescence. The expressions of type Ⅰ collagen and TGF-ß1 in scar Fbs cytoplasm of the elderly group were significantly higher than those in the young group, while the expressions of α-SMA in scar Fbs cytoplasm were close in the two groups. The expressions of YAP in cytoplasm and nucleus of scar Fbs in the elderly group were significantly higher than those in the young group, while the expressions of Ki67 in scar Fbs nucleus of the two groups were close. The mRNA expressions of TGF-ß1 and type Ⅰ collagen in scar Fbs of the elderly group were significantly higher than those in the young group (t=2.87, 4.85, P<0.05 or P<0.01), the mRNA expression of TGF-ß3 in scar Fbs of the elderly group was significantly lower than that in the young group (t=3.36, P<0.05), and the mRNA expressions of α-SMA in scar Fbs of the two groups were close (t=1.14, P>0.05). The mRNA expressions of ROCK1 and YAP in scar Fbs of the elderly group were significantly higher than those in the young group (t=2.98, 7.60, P<0.05 or P<0.01). Conclusions: The elderly are prone to scar healing after skin injury. The molecular mechanism may be attributed to the production of extracellular matrix components with higher stiffness, which increases tissue stiffness and thereby activates the expressions of ROCK and YAP/transcriptional co-activator with PDZ-binding motif genes, promoting pro-fibrosis gene and protein expression.