Mesenchymal stem cell‐derived exosomes (MSC‐Ex) play important roles in tissue injury repair, however, the roles of MSC‐Ex in skin damage repair and its mechanisms are largely unknown. Herein, we ...examined the benefit of human umbilical cord MSC‐derived exosome (hucMSC‐Ex) in cutaneous wound healing using a rat skin burn model. We found that hucMSC‐Ex‐treated wounds exhibited significantly accelerated re‐epithelialization, with increased expression of CK19, PCNA, collagen I (compared to collagen III) in vivo. HucMSC‐Ex promoted proliferation and inhibited apoptosis of skin cells after heat‐stress in vitro. We also discovered that Wnt4 was contained in hucMSC‐Ex, and hucMSC‐Ex‐derived Wnt4 promoted β‐catenin nuclear translocation and activity to enhance proliferation and migration of skin cells, which could be reversed by β‐catenin inhibitor ICG001. In vivo studies confirmed that the activation of Wnt/β‐catenin by hucMSC‐Ex played a key role in wound re‐epithelialization and cell proliferation. Furthermore, knockdown of Wnt4 in hucMSC‐Ex abrogated β‐catenin activation and skin cell proliferation and migration in vitro. The in vivo therapeutic effects were also inhibited when the expression of Wnt4 in hucMSC‐Ex was interfered. In addition, the activation of AKT pathway by hucMSC‐Ex was associated with the reduction of heat stress‐induced apoptosis in rat skin burn model. Collectively, our findings indicate that exosome‐delivered Wnt4 provides new aspects for the therapeutic strategy of MSCs in cutaneous wound healing. Stem Cells 2015;33:2158–2168
In the process of airborne gravity gradiometry for the full-tensor airborne gravity gradiometer (FTAGG), the attitude of the carrier and the fuel mass will seriously affect the accuracy of gravity ...gradiometry. A self-gradient is the gravity gradient produced by the surrounding masses, and the surrounding masses include distribution mass for the carrier mass and fuel mass. In this paper, in order to improve the accuracy of airborne gravity gradiometry, a self-gradient compensation model is proposed for FTAGG. The self-gradient compensation model is a fuction of attitude for carrier and time, and it includes parameters ralated to the distribution mass for the carrier. The influence of carrier attitude and fuel mass on the self-gradient are simulated and analyzed. Simulation shows that the self-gradient tensor element Γ x x , Γ x y , Γ x z , Γ y z and Γ z z are greatly affected by the middle part of the carrier, and the self-gradient tensor element Γ y z is affected by the carrier's fuel mass in three attitudes. Further simulation experiments show that the presented self-gradient compensation method is valid, and the error of the self-gradient compensation is within 0.1 Eu. Furthermore, this method can provide an important reference for improving the accuracy of aviation gravity gradiometry.
Our research aimed to explore the correlation between mid-upper arm circumference (MUAC) and central obesity and insulin resistance (IR) in Chinese subjects with type 2 diabetes.
A total of 103 ...participants (60 men) were recruited in our study. MUAC was measured around the mid-arm between the shoulder and elbow. Waist circumference (WC) was obtained as central obesity parameter, and the IR parameter of Homeostasis Model Assessment-Insulin Resistance (HOMA-IR) was calculated. The subjects were divided into three groups according to the tertiles cut-points of MUAC level.
Body mass index (BMI), WC, the percentages of central obesity and HOMA-IR were significantly higher in the groups with higher MUAC than those in the group with lower MUAC (all P < 0.05). Pearson analysis showed that MUAC was correlated with BMI, WC, waist-to-hip ratio (WHR), logHOMA-IR, low density lipoprotein cholesterol (LDL-C), uric acid (UA) and high density lipoprotein cholesterol (HDL-C) in all subjects. Multivariate linear regression analysis revealed that MUAC was independently associated with logHOMA-IR (β = 0.036, P<0.001) after adjusting for age, gender, WHR, UA, TG, LDL-C and HDL-C. Binary logistic regression analysis revealed that MUAC was an independent predictor of central obesity (OR: 2.129, 95%CI: 1.311-3.457, P = 0.002). Furthermore, MUAC≥30.9cm for male and ≥30.0cm for female were the optimal cutoff values for identifying central obesity.
Our study indicated that among Chinese subjects with type 2 diabetes, MUAC is a simple and effective tool for the determination of central obesity and IR. Additionally, the larger MUAC is proved to be more associated with metabolic risk factors of higher UA and LDL-C and lowever HDL-C.
(ToLCGdV) is a begomovirus associated with a Tomato yellow leaf curl disease (TYLCD) epidemic in Guangdong province, China. Being the least conserved protein among geminivirus proteins, the function ...of C4 during ToLCGdV infection has not been elucidated. In this study, the infectious clones of ToLCGdV and a ToLCGdV mutant (ToLCGdV
) with disrupted C4 ORF were constructed. Although ToLCGdV and ToLCGdV
could infect
and tomato plants, ToLCGdV
elicited much milder symptoms compared with ToLCGdV. To further verify the role of C4 in viral pathogenesis, C4 was expressed in
from
(PVX) vector. The results showed that ToLCGdV C4 enhanced the pathogenicity of PVX and induced more severe developmental abnormalities in plants compared with PVX alone or PVX-mC4. In addition, ToLCGdV C4 suppresses systemic gene silencing in the transgenic
line 16c, but not local gene silencing induced by sense GFP in wild-type
plants. Moreover, C4 suppresses transcriptional gene silencing (TGS) by reducing the DNA methylation level of 35S promoter in 16c-TGS
plants. Furthermore, C4 could also interact with the receptor-like kinase (RLK) BARELY ANY MERISTEM 1 (BAM1), suggesting that C4 may suppress gene silencing by interfering with the function of BAM1 in the cell-to-cell spread of RNAi. All these results suggest that C4 is a pathogenic determinant of ToLCGdV, and C4 may suppress post-transcriptional gene silencing (PTGS) by interacting with BAM1.
•Seasonal variation in leaf stoichiometry and WUE was closely coupled.•Temperature may be the main driver of seasonal changes in stoichiometry and WUE.•Stable carbon isotope composition may be ...integrated in future Earth system models.
Estimates of seasonal variation in plant stoichiometry and water use efficiency (WUE) are critical for predicting the time courses of carbon and water fluxes. However, the relationship between seasonal stoichiometry and WUE, and their relationship with climatic factors remains unclear. The carbon isotope composition has been widely used to evaluate the WUE. We hypothesized that WUE is closely related to seasonal variation in plant stoichiometry, and then stable carbon isotope can be used to indicate the variation in future models. For this study, we investigated seasonal changes in WUE and 14 elements (C, N, P, S, K, Na, Ca, Mg, Al, Fe, Mn, Zn, Cu, and Ba) of Quercus variabilis in a warm temperate forest, Central China. The WUE gradually reduced from late spring until leaf senescence in fall. Leaf C and N initially increased and then decreased. Leaf P, S, and K generally decreased, whereas Ca, Ba, Al and Fe gradually accumulated throughout the growing season. Leaf C:N, C:P, and N:P were lowest in early season, and then typically increased. As expected, WUE was positively correlated with N, P, S, K, and Mg, while negatively with C, Ca, Al, and Fe as well as C:N, C:P, and N:P. WUE increased with higher temperatures but had no relationship with precipitation. Leaf N, P, S, and K increased, while C:N, C:P, and N:P decreased with higher temperatures. Our results suggested that seasonal stoichiometry and WUE was closely coupled with plant growth, and temperature may be the main dynamic driver of water and nutrients in forest ecosystems. As WUE was estimated by carbon isotope composition, our findings provide new insights toward integrating carbon isotope with Earth system models.
Excessive free radicals and iron death lead to oxidative damage, which is one of the main causes of aging and diseases. In this field of antioxidation, developing new, safe, and efficient ...antioxidants is the main research focus. Lactic acid bacteria (LAB) are natural antioxidants with good antioxidant activity and can regulate gastrointestinal microecological balance and immunity. In this study, 15 LAB strains from fermented foods ("Jiangshui" and pickles) or feces were evaluated in terms of their antioxidant attributes. Strains with strong antioxidant capacity were preliminarily screened by the following tests: 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical, superoxide anion radical scavenging capacity; ferrous ion chelating assay; hydrogen peroxide tolerance capacity. Then, the adhesion of the screened strains to the intestinal tract was examined using hydrophobic and auto-aggregation tests. The safety of the strains was analyzed based on their minimum inhibitory concentration and hemolysis, and 16S rRNA was used for molecular biological identification. Antimicrobial activity tests showed them probiotic function. The cell-free supernatant of selected strains were used to explore the protective effect against oxidative damage cells. The scavenging rate of DPPH, hydroxyl radicals, and ferrous ion-chelating of 15 strains ranged from 28.81-82.75%, 6.54-68.52%, and 9.46-17.92%, respectively, the scavenging superoxide anion scavenging activity all exceeded 10%. According to all the antioxidant-related tests, strains possessing high antioxidant activities J2-4, J2-5, J2-9, YP-1, and W-4 were screened, these five strains demonstrated tolerance to 2 mM hydrogen peroxide. J2-4, J2-5, and J2-9 were
and γ-hemolytic (non-hemolytic). YP-1 and W-4 were
and α-hemolytic (grass-green hemolytic). Although
has been proven as a safe probiotic without hemolytic characteristics, the hemolytic characteristics of YP-1 and W-4 should be further studied. Due to the weak hydrophobicity and antimicrobial activity of J2-4, finally, we selected J2-5, J2-9 for cell experiment, J2-5 and J2-9 showed an excellent ability that resistant to oxidative damage by increasing SOD, CAT, T-AOC activity of 293T cells. Therefore, J2-5, and J2-9 strains from fermented foods "Jiangshui" could be used as potential antioxidants for functional food, health care, and skincare.
Abstract Background The relationship between glycemic variability, another component of glycemic disorders as well as chronic sustained hyperglycemia, and cardiovascular autonomic neuropathy (CAN) ...has not been clarified. Our aim is to investigate the association between glycemic variability and CAN in newly diagnosed type 2 diabetic patients. Methods Ewing tests were performed in 90 newly diagnosed type 2 diabetic patients and 37 participants with normal glucose tolerance as control from May 1, 2009, through September 30, 2010. According to the scores from Ewing tests, diabetic patients were divided into two groups: without CAN (CAN −) and with CAN (CAN +). All participants underwent a 48-h to 72-h continuous glucose monitoring (CGM). Coefficient of variability of glycemia (%CV), mean amplitude of glycemic excursions (MAGE) and means of daily differences (MODD) were calculated with the CGM data. Results The prevalence of CAN in patients with newly diagnosed type 2 diabetes was 22.2%. An increasing trend of glycemic variability was found from control group, CAN − group to CAN + group. MAGE in CAN + group was significantly higher than that in CAN − group (5.27 ± 1.99 mmol/L vs. 4.04 ± 1.39 mmol/L, P = 0.001). In the Logistic regression analysis, a significant relationship was shown between MAGE and CAN odds ratio (OR): 1.73, 95% confidence interval (CI): 1.01–2.73, P = 0.018). The area under the receiver-operating characteristic curve for MAGE was superior to those for other dysglycemic indices in detecting CAN. Conclusions Glycemic variability is associated with CAN in patients with newly diagnosed type 2 diabetes. Among the glycemic variability indices, MAGE is a significant indicator for detecting CAN.
A plasma electrolytic nitrocarburizing (PEN/C) process was performed on the Q235 steel in an aqueous solution of urea to modify the surface properties. The decomposing particles of organic compounds ...in the electrolyte adjacent to the electrode were obtained using ultraviolet spectrum during the process. The outer surface (2–5nm) was analyzed using X-ray photoelectron spectroscope (XPS). The cross-section and the surface morphologies were investigated using optical microscope and scanning electron microscope (SEM) equipped with energy dispersive spectroscope (EDS). The microstructure was determined using X-ray diffraction (XRD). Hardness and roughness were evaluated using micro-hardness tester and roughness meter. The wear of the samples were measured using pin-disk friction and wear testing machine in dry condition. It is indicated that urea electrolyte is ionized into conjugated double bonds consisting of carbon, nitrogen and oxygen. The micro-pores are uniformly distributed on the surface of the PEN/C samples. Iron carbide, iron nitride, CC hydrocarbon and iron oxide are formed on the outer surface of the PEN/C samples. The content of carbon and nitrogen in the diffusion layer is higher than that in the substrate. The diffusion layer mainly contains phases in Fe3C and Fe4N. The micro-hardness of the diffusion layer is 3 to 4 times higher than that of the substrate. The roughness of the surface is increased with prolong of time. The wear of the PEN/C sample is improved greatly, and this will enhance the service life of steel.
► The formation, adsorption and diffusion processes of the PEN/C particles are studied. ► The XPS of the nanometer scale of the outer surface is carried out. ► The micro-pores are uniformly distributed on the surface of the PEN/C sample. ► The performance of the surface on the PEN/C sample is improved.
Ce(NO3)3 and Na2MoO4 are adopted to form (Mo-Ce) composite corrosion inhibitor in allusion to the corrosion problem of steel in acidic conditions. The experimental results showed that the ...anticorrosion effects were enhanced and the inhibition efficiencies were increased by (NH4)2S2O8. The reason of enhancement is the increase of coordination bonds amount between Ce4+ and , the augment of combining sites of interface between anti-corrosion film and steel, and the reinforce of adsorption caused by the transformation of Ce3+ to Ce4+ by oxidants. The process and conditions for transformation of Ce3+ to Ce4+ and formation of complexes are discussed. The related thermodynamic and kinetic parameters are calculated and the possibility for (NH4)2S2O8 to improve the performance of Mo-Ce corrosion inhibitor is proved.
Diabetic retinopathy (DR) is a major cause of blindness and is characterized by dysfunction of the retinal microvasculature. Neutrophil stasis, resulting in retinal inflammation and the occlusion of ...retinal microvessels, is a key mechanism driving DR. These plugging neutrophils subsequently release neutrophil extracellular traps (NETs), which further disrupts the retinal vasculature. Nevertheless, the primary catalyst for NETs extrusion in the retinal microenvironment under diabetic conditions remains unidentified. In recent studies, cellular communication network factor 1 (CCN1) has emerged as a central molecule modulating inflammation in pathological settings. Additionally, our previous research has shed light on the pathogenic role of CCN1 in maintaining endothelial integrity. However, the precise role of CCN1 in microvascular occlusion and its potential interaction with neutrophils in diabetic retinopathy have not yet been investigated.
We first examined the circulating level of CCN1 and NETs in our study cohort and analyzed related clinical parameters. To further evaluate the effects of CCN1 in vivo, we used recombinant CCN1 protein and CCN1 overexpression for gain-of-function, and CCN1 knockdown for loss-of-function by intravitreal injection in diabetic mice. The underlying mechanisms were further validated on human and mouse primary neutrophils and dHL60 cells.
We detected increases in CCN1 and neutrophil elastase in the plasma of DR patients and the retinas of diabetic mice. CCN1 gain-of-function in the retina resulted in neutrophil stasis, NETs extrusion, capillary degeneration, and retinal leakage. Pre-treatment with DNase I to reduce NETs effectively eliminated CCN1-induced retinal leakage. Notably, both CCN1 knockdown and DNase I treatment rescued the retinal leakage in the context of diabetes. In vitro, CCN1 promoted adherence, migration, and NETs extrusion of neutrophils.
In this study, we uncover that CCN1 contributed to retinal inflammation, vessel occlusion and leakage by recruiting neutrophils and triggering NETs extrusion under diabetic conditions. Notably, manipulating CCN1 was able to hold therapeutic promise for the treatment of diabetic retinopathy.
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