Mesenchymal stem cells (MSCs) are a group of stem cells derived from the mesodermal mesenchyme. MSCs can be obtained from a variety of tissues, including bone marrow, umbilical cord tissue, umbilical ...cord blood, peripheral blood and adipose tissue. Under certain conditions, MSCs can differentiate into many cell types both in vitro and in vivo, including hepatocytes. To date, four main strategies have been developed to induce the transdifferentiation of MSCs into hepatocytes: addition of chemical compounds and cytokines, genetic modification, adjustment of the micro‐environment and alteration of the physical parameters used for culturing MSCs. Although the phenomenon of transdifferentiation of MSCs into hepatocytes has been described, the detailed mechanism is far from clear. Generally, the mechanism is a cascade reaction whereby stimulating factors activate cellular signalling pathways, which in turn promote the production of transcription factors, leading to hepatic gene expression. Because MSCs can give rise to hepatocytes, they are promising to be used as a new treatment for liver dysfunction or as a bridge to liver transplantation. Numerous studies have confirmed the therapeutic effects of MSCs on hepatic fibrosis, cirrhosis and other liver diseases, which may be related to the differentiation of MSCs into functional hepatocytes. In addition to transdifferentiation into hepatocytes, when MSCs are used to treat liver disease, they may also inhibit hepatocellular apoptosis and secrete various bioactive molecules to promote liver regeneration. In this review, the capacity and molecular mechanism of MSC transdifferentiation, and the therapeutic effects of MSCs on liver diseases are thoroughly discussed.
To assess prevalence and associated factors of changes in the ophthalmoscopic optic disc size and shape.
The case-control study included all highly myopic eyes (myopic refractive error ≤-6.0 ...diopters) and a randomly selected group of non-highly myopic eyes, examined in the population-based Beijing Eye Study 2001 and 2011.
The study included 89 highly myopic eyes (age:65.0±9.8 years) and 86 non-highly myopic eyes. Reduction in ophthalmoscopic disc size (prevalence, high myopia: 30 (33.7%) eyes; non-high myopia: 7 (8.1%) eyes) was associated with non-circular gamma zone enlargement (OR: 19.4; 95% CI: 6.7 to 56.6; p<0.001) and disc-fovea line elongation (OR: 2.80;95% CI: 1.12 to 6.98; p=0.03). Disc size reduction was correlated with a disc diameter shortening in direction of the widest gamma zone enlargement (correlation coefficient r=34; p=0.01). The perpendicular disc diameter remained mostly unchanged, resulting in an ovalisation of the ophthalmoscopic disc shape. Enlargement of the ophthalmoscopic disc size (prevalence, high myopia: 22 (24.7%) eyes; non-high myopia: 4 (4.7%) eyes) was associated with circular gamma zone enlargement (4.99; 95% CI: 1.95 to 12.8; p=0.001) and high myopia (OR: 4.29; 95% CI: 1.34 to 13.8; p=0.01).
Myopic axial elongation may lead first to a Bruch's membrane (BM) opening (BMO) shift into the foveal direction leading to BM overhanging into the nasal intrapapillary compartment, development and enlargement of gamma zone at the temporal disc side, reduction in the ophthalmoscopically visible disc area and ovalisation of the ophthalmoscopic disc shape. In a second step, an axial elongation-associated BMO enlargement may lead to a circular gamma zone increase and, due to the retraction of BM at the nasal disc border, to an enlargement of the ophthalmoscopically visible optic disc.
Due to the condensation reaction of hydroxylated melamine molecules is possible to take place in the whole pH range, especially in acidic water medium or at high temperature, losing its water ...solubility. In this work, freeze drying perfectly removes water at pretty low temperature, avoiding condensation reaction of hydroxylated melamine. Therefore, a hydroxylated melamine in solid form (MOH‐S) was prepared. It can be not only dissolved in water after storing for 180 days but also well dispersed in waterborne polyurethane emulsion. The addition of hydroxylated melamine significantly improves the tensile strength of polyurethane films by 170%. After soaking the films in water for 24 h, the tensile strength of WPU/30%MOH‐S film lost only 6%, but 34% loss for the neat. Fourier transform infrared spectroscopy peak fitting demonstrates that the H‐bonding degree of N─H in WPU/30%MOH‐S film is 20.72 that is much higher than 3.33 in neat WPU. This indicates that H‐bonding cross‐linked structure is formed between polyurethane chains and hydroxylated melamine molecules. This work provides an effective strategy for preparing stable hydroxylated melamine and enhancing the strength of polyurethane film.
Irisin is a cleaved and secreted fragment of fibronectin type III domain containing 5 (FNDC5), and contributes to the beneficial effects of exercise on metabolism. Here we report the therapeutical ...effects of FNDC5/irisin on metabolic derangements and insulin resistance in obesity, and show the lipolysis effect of irisin and its signal molecular mechanism. In obese mice, lentivirus mediated-FNDC5 overexpression enhanced energy expenditure, lipolysis and insulin sensitivity, and reduced hyperlipidemia, hyperglycemia, hyperinsulinism, blood pressure and norepinephrine levels; it increased hormone-sensitive lipase (HSL) expression and phosphorylation, and reduced perilipin level and adipocyte diameter in adipose tissues. Subcutaneous perfusion of irisin reduced hyperlipidemia and hyperglycemia, and improved insulin resistance. Either FNDC5 overexpression or irisin perfusion only induced a tendency toward a slight decrease in body weight in obese mice. In 3T3-L1 adipocytes, irisin enhanced basal lipolysis rather than isoproterenol-induced lipolysis, which were prevented by inhibition of adenylate cyclase or PKA; irisin increased the HSL and perilipin phosphorylation; it increased PKA activity, and cAMP and HSL mRNA levels, but reduced perilipin expression. These results indicate that FNDC5/irisin ameliorates glucose/lipid metabolic derangements and insulin resistance in obese mice, and enhances lipolysis via cAMP–PKA–HSL/perilipin pathway. FNDC5 or irisin can be taken as an effective therapeutic strategy for metabolic disorders.
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•FNDC5/irisin ameliorates glucose/lipid metabolic derangements in obesity.•FNDC5/irisin reduces blood glucose and improves insulin resistance in obesity.•FNDC5/irisin enhances lipolysis via cAMP–PKA–HSL pathway.
A series of multifunctional photoluminescent materials, pyrrolidinium2MnBr4 (1), N‐methylpyrrolidinium2MnBr4 (2), and N‐methylpyrrolidiniumMnBr3 (3), were obtained by means of regulating diverse ...organic cations and different coordination modes of inorganic metal ions. Interestingly, compounds 1, 2, and 3 exhibit different dielectric switching and relaxation behavior in the process of structural transformations. Furthermore, compounds 1, 2, and 3 possess intriguing photoluminescence properties. When subjected to UV light, tetrahedrally coordinated compound 1 shows extraordinarily strong green light emission with a high quantum yield of 51.41 %. By changing the organic cation, compound 2 exhibits an unusual orange emission under ultraviolet excitation, which is different from that of conventional tetrahedrally coordinated manganese‐based compounds. By the regulation of coordination modes of inorganic metal ions, octahedrally coordinated compound 3 emits bright red light with a high quantum yield of 36.76 %. This finding may open a new approach toward designing multifunctional photoluminescent materials.
Three compounds not only exhibit different dielectric behavior but also reveal interesting photoluminescence properties. Compound 1 shows strong green light emission, compound 2 exhibits unusual orange emission, and compound 3 has bright red emission.
To examine the distribution of intraocular pressure (IOP) in a normal population and the associations of IOP with other ocular and systemic parameters.
Out of 3468 participants of the ...population-based cross-sectional Beijing Eye Study 2011 we selected those individuals without glaucomatous optic neuropathy. The study particpants underwent a detailed ophthalmologic and systemic examination. IOP was measured by air puff non-contact tonometry.
The study included 3135 eyes of 3135 participants with a mean age of 64.1 ± 9.6 years (mean ± standard deviation). The mean IOP was 14.7 ± 2.8 mmHg. The 95% percentile and 97.5% percentile of the IOP distribution decreased from 20 mmHg / 21 mmHg in individuals aged 40 to 54 years to 18 mmHg / 19 mmHg in individuals aged ≥80 years. In multivariable analysis, higher IOP was associated with the systemic parameters of younger age (P<0.001), higher blood concentration of glucose (P = 0.03) and triglycerides (P<0.001), higher diastolic blood pressure (P<0.001), higher pulse rate (P = 0.003) and higher quantity of alcohol consumption (P = 0.004), and with the ocular parameters of larger central corneal thickness (P<0.001), more myopic refractive error (P = 0.01) and steeper anterior corneal curvature radius (P = 0.006). IOP decreased significantly by 0.50 mmHg and 0.76 mmHg for each increase in age by 10 years and each increase in corneal curvature radius by 1.0 mm, respectively. The range of the mean ± 2 standard deviations of the IOP adjusted for the parameters of the multivariable model was 9.0 to 18.1 mmHg versus 9.2-20.2 mmHg for the unadjusted IOP. In the age group of 50 to 55 years, the age-adjusted IOP range (mean ± 2 standard deviations) was 9 to 18 mmHg, and in the age group of ≥75 years, it was 8 to 18 mmHg.
IOP physiologically depends on a multitude of systemic and ocular factors including age and blood pressure. These physiological associations of the IOP may be taken into account in the definition of the normal range of the IOP.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Salt stress is one of the key factors limiting rice production. Alginate oligosaccharides (AOS) enhance plant stress resistance. However, the molecular mechanism underlying salt tolerance in rice ...induced by AOS remains unclear. FL478, which is a salt-tolerant indica recombinant inbred line and IR29, a salt-sensitive rice cultivar, were used to comprehensively analyze the effects of AOS sprayed on leaves in terms of transcriptomic and metabolite profiles of rice seedlings under salt stress. In this experiment, exogenous application of AOS increased SOD, CAT and APX activities, as well as GSH and ASA levels to reduce the damage to leaf membrane, increased rice stem diameter, the number of root tips, aboveground and subterranean biomass, and improved rice salt tolerance. Comparative transcriptomic analyses showed that the regulation of AOS combined with salt treatment induced the differential expression of 305 and 1030 genes in FL478 and IR29. The expressed genes enriched in KEGG pathway analysis were associated with antioxidant levels, photosynthesis, cell wall synthesis, and signal transduction. The genes associated with light-trapping proteins and RLCK receptor cytoplasmic kinases, including CBA, LHCB, and Lhcp genes, were fregulated in response to salt stress. Treatment with AOS combined with salt induced the differential expression of 22 and 50 metabolites in FL478 and IR29. These metabolites were mainly related to the metabolism of amino and nucleotide sugars, tryptophan, histidine, and beta -alanine. The abundance of metabolites associated with antioxidant activity, such as 6-hydroxymelatonin, wedelolactone and L-histidine increased significantly. Combined transcriptomic and metabolomic analyses revealed that dehydroascorbic acid in the glutathione and ascorbic acid cycles plays a vital role in salt tolerance mediated by AOS. AOS activate signal transduction, regulate photosynthesis, cell wall formation, and multiple antioxidant pathways in response to salt stress. This study provides a molecular basis for the alleviation of salt stress-induced damage by AOS in rice.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To determine the prevalence and progression of myopic retinopathy in Chinese adults.
Population-based cross-sectional study.
The Beijing Eye Study 2001 included 4439 subjects of 5324 individuals who ...were invited to participate (response rate, 83.4%); the eligibility criterion was an age of 40+ years. The study was repeated in 2006, with 3251 subjects (73.2%) participating.
The participants underwent a detailed eye examination, including fundus photography. Myopic retinopathy was defined by posterior staphylomata, lacquer cracks, Fuchs' spot of the macula, and myopic chorioretinal atrophy at the posterior pole. Parapapillary atrophy was assessed separately.
Prevalence of myopic retinopathy and its change during a follow-up of 5 years.
After exclusion of pseudophakic or aphakic eyes, and eyes without assessable fundus photographs, 4319 subjects (97.3%) were included in the present study. Myopic retinopathy was present in 198 eyes (2.3%+/-0.2%; 95% confidence interval CI, 2.0-2.6) of 132 participants (3.1%). Myopic retinopathy was significantly associated with higher age (P<0.001), worse best-corrected visual acuity (P<0.001), deeper anterior chamber (P = 0.04), larger optic disc (P<0.001), less age-related macular degeneration (P = 0.02; odds ratio OR 0.90), and greater prevalence of open-angle glaucoma (P<0.001; OR 4.42). Myopic retinopathy was not associated significantly (P>0.20) with body height and weight, gender, rural versus urban region of residence, level of education, intraocular pressure, or central corneal thickness. The prevalence of myopic retinopathy increased significantly (P<0.001) with increasing myopic refractive error, from 3.8% in eyes with a myopic refractive error of < -4.0 diopters to 89.6% in eyes with a myopic refractive error of at least -10.0 diopters. At the 5-year follow-up examination, enlargement of the chorioretinal atrophy at the posterior fundus was observed in 9% of the eyes.
Myopic retinopathy was present in 3.1% of subjects aged 40+ years who resided in the Greater Beijing area. Myopic retinopathy was associated with increased age, worse best-corrected visual acuity, deeper anterior chamber, larger optic disc, less age-related macular degeneration, and higher prevalence of open-angle glaucoma.
To assess the 10-year incidence of open-angle glaucoma (OAG) and its associations in an adult Chinese population.
Longitudinal observational population-based study. Out of 4439 participants aged 40+ ...years participating in the Beijing Eye Study in 2001, 2695 individuals (60.7%) were re-examined in 2011, while 397 participants had died (8.5%).
Incident OAG was found in 75 participants among 2494 individuals free of glaucoma at baseline. The 10-year OAG incidence (mean: 3.0%; 95% CI 2.5 to 3.5) increased from 1.8% (95% CI 1.3 to 2.4) in individuals aged 40-49 years, to 5.9% (95% CI 3.1 to 9.6) in participants aged 70+ years. OAG incidence was highest in the high myopia group (13.3%±6.3%, OR: 7.3; 95% CI 3.3 to 16.3), followed by the moderately myopic group (8.1%±4.3%, OR: 4.2; 95% CI 2.0 to 8.8) and the low myopic group (6.2%±2.8%, OR: 3.2; 95% CI 1.7 to 5.8), as compared with the emmetropic/hyperopic group (2.1%±0.8%). In multivariable analysis, higher OAG incidence was associated with older age (OR: 1.06; 95% CI 1.03 to 1.09), longer axial length (OR: 1.72; 95% CI 1.45 to 2.05), higher intraocular pressure (IOP) in 2001 (OR: 1.18; 95% CI 1.08 to 1.29), higher vertical cup/disc ratio (VCDR) (OR: 60.8; 95% CI 6.7 to 556) and thinner central corneal thickness (CCT) (OR: 0.98; 95% CI 0.97 to 0.99).
In a 10-year follow-up, high myopia was a major risk factor for the development of OAG with a 7.3-fold risk increase as compared with emmetropic eyes. Higher age, IOP, VCDR and thinner CCT were additionally related with an increased OAG incidence. The findings may be of importance to clinical protocols and screening strategies.
The beet armyworm, Spodoptera exigua, is a significant agricultural pest of numerous crops and has caused serious economic losses in China. To effectively control this pest, we analyzed its genetic ...variation, population genetic structure and demographic history. We used mitochondrial DNA (mtDNA) fragments of the cytochrome oxidase subunit I (COI) and eight nuclear microsatellite loci to investigate genetic diversity and population genetic structure of S. exigua populations at 14 sampling sites in western China. Both mtDNA and microsatellite data indicated low levels of genetic diversity among all populations. A moderate genetic differentiation among some S. exigua populations was detected. Neighbor-joining dendrograms, STRUCTURE, and principal coordinate analysis (PCoA) revealed two genetically distinct groups: the KEL group and the remaining population group. Isolation by distance (IBD) results showed a weak significant correlation between geographic distance and genetic differentiation. Haplotype networks, neutrality testing, and mismatch distribution analysis indicated that the beet armyworm experienced a recent rapid expansion without a recent genetic bottleneck in western China. Thus, the results of this population genetic study can help with the development of strategies for managing this highly migratory pest.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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