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1.
J Nanosci Nanotechnol ; 20(3): 1756-1764, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492340

RESUMO

Organic-inorganic CoFe2O4/polyaniline (CoFe2O4/PA) nanocomposites with embedded structures were synthesized by combining the sol-gel auto-combustion process and in-situ oxidative polymerization. The phases and morphologies of the prepared samples were identified. The pure CoFe2O4 samples exhibited inferior microwave-absorption properties in a frequency range of 2-18 GHz. Upon the incorporation of PA, the formed CoFe2O4/PA nanocomposites exhibited rather good absorption performances. When the sample thickness was 2.5 mm, the maximum reflection loss (RL) reached -22.3 dB, while the RL below -10 dB corresponded to the range of 11.0-17.1 GHz, which contains almost the entire Ku-band, making the structure promising for commercial and military applications. A physical model was employed to explain the effects of the embedded structure on the microwave-absorption performances. The excellent microwave-absorption performances could be attributed to the interfacial polarization and repeated reflection of the microwaves inside the CoFe2O4/PA composite.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 224: 117384, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31336321

RESUMO

Chemosensing is one of the widest and powerful techniques for response to anions and cations in living systems serving as bio-probes. Meanwhile, copper(II) (Cu(II)) widely exists in the environment and the human body as a common trace element, which plays an necessary role in most physiological processes. Thus, it is extremely urgent to explore means for effective, rapid and convenient detection of Cu(II) in living cells. Herein, we introduce a novel strategy for designing triphenylamine (TS) and coumarin-based (CS) functional sensors for Cu(II) detection with fluorescence "OFF" switching mechanism by blocking intramolecular charge transfer (ICT). Based on this design strategy, we have demonstrated two kinds of fluorophores sensors with aunique new fluorescent dye and excellent photophysical properties, which have shown rapid recognition of Cu(II) via a stoichiometric ratio of 2:1 and the proposed binding mode was confirmed by the single-crystal structure of CS-Cu(II) complex. In addition, we have carried out density functional theory (DFT) calculation with the B3LYP exchange functional employing RB3LYP/6-31G basis sets to get insight into the mechanism of Cu(II)-sensors alongside their optical properties. Furthermore, the sensors were capable of bio-imaging Cu(II) in living cancer cells (HepG2, A549 and Hela) with low cytotoxicity and good biocompatibility shown. Taken together, We expect that this novel strategy would provide new insight into the development of Cu(II) detection techniques and could be used more for biomedical applications.

3.
Behav Brain Res ; 377: 112249, 2020 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-31541673

RESUMO

Negative mood states are hypothesized to increase the risk for overeating among restrained eaters. However, neurophysiological features of inhibitory control during negative mood states among restrained eaters are poorly understood. To address this gap, we aimed to assess event related potentials (ERPs) associated with food-specific inhibitory control among successful restrained eaters (SREs, n = 17), unsuccessful restrained eaters (UREs, n = 18), and non-restrained eaters (NREs, n = 18) engaged in a food-related go/no-go task during negative versus neutral mood states. Compared to neutral mood states, negative mood states were related to comparatively greater no-go N2a amplitudes in the entire sample. Regarding group differences, no-go N2a amplitudes of SREs were greater than those of UREs across negative and neutral mood states. However, no-go P3 amplitudes of SREs decreased significantly during the negative mood state while no change was observed for other groups. Results suggest that negative mood states may interfere with conflict monitoring and behavioral inhibition in general, but inhibitory control over food may be enhanced among SREs during negative mood states relative to UREs. Results may provide psychophysiological bases for understanding why SREs succeed and UREs fail in controlling appetitive responses to external food cues.

4.
Am J Surg ; 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31668709

RESUMO

BACKGROUND: The objective of this study was to validate the transfer of ultrasound-guided Internal Jugular Central Venous Catheterization (US-IJCVC) placement skills from training on a Dynamic Haptic Robotic Trainer (DHRT), to placing US-IJCVCs in clinical environments. DHRT training greatly reduces preceptor time by providing automated feedback, standardizes learning experiences, and quantifies skill improvements. METHODS: Expert observers evaluated DHRT-trained (N = 21) and manikin-trained (N = 36) surgical residents on US-IJCVC placement in the operating suite using a US-IJCVC evaluation form. Performance and errors by DHRT-trained residents were compared to traditional manikin-trained residents. RESULTS: There were no significant training group differences between unsuccessful insertions (p = 0.404), assistance on procedure (p = 0.102), arterial puncture (p = 0.998), and average number of insertion attempts (p = 0.878). Regardless of training group, previous central line experience significantly predicted whether residents needed assistance on the procedure (p = 0.033). CONCLUSION: The results failed to show a statistical difference between DHRT- and manikin-trained residents. This study validates the transfer of skills from training on the DHRT system to performing US-IJCVC in clinical environments.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31668812

RESUMO

The inflammatory hypothesis is one of the most important mechanisms of depression. Fucoidan is a bioactive sulfated polysaccharide abundant in brown seaweeds with anti-inflammatory activity. However, the antidepressant effects of fucoidan on chronic stress-induced depressive-like behaviors have not been well elucidated. Here, we used two different depressive-like mouse models, lipopolysaccharide (LPS) and chronic restraint stress (CRS) models, to explore the detailed molecular mechanism underlying its antidepressant-like effects in C57BL/6J mice by combining multiple behavioral, molecular and immunofluorescence experiments. Adenovirus-mediated overexpression of caspase-1 and pharmacological inhibitors were also used to clarify the antidepressant mechanisms of fucoidan. We found that acute administration of fucoidan did not produce antidepressant effects in the tail suspension test (TST) and forced swim test (FST). Interestingly, chronic fucoidan administration not only dose-dependently reduced stress-induced depressive-like behaviors in the TST, FST, sucrose preference test (SPT), and novelty-suppressed feeding test (NSFT), but also alleviated the downregulation of brain-derived neurotrophic factor (BDNF)-dependent synaptic plasticity via inhibiting caspase-1-mediated inflammation in the hippocampus of mice. Moreover, fucoidan significantly ameliorated behavioral and synaptic plasticity abnormalities in the overexpression of caspase-1 in the hippocampus of mice. Furthermore, blocking BDNF abolished the antidepressant-like effects of fucoidan in mice. Therefore, our findings clearly indicate that fucoidan provides a potential supplementary noninvasive treatment for depression by inhibition of hippocampal inflammation.

6.
Environ Res ; 180: 108843, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31670082

RESUMO

BACKGROUND: Previous studies have shown that ambient air pollution exposure can increase the risk of type 2 diabetes mellitus (T2DM) significantly. In consideration of the common underlying pathophysiologic mechanisms, exposure to air pollution may also increase the risk of gestational diabetes mellitus (GDM), but the current evidence was inconsistent and has not well been systematically reviewed. Our goal was to perform a systematic review and meta-analysis assessing the association between air pollution exposure and GDM. METHODS: An extensive literature search was conducted in selected electronic databases for related human epidemiological studies published in English language. Summary effect estimates were calculated using random-effect models for a) risk per unit increase in continuous air pollutant concentration and b) risk of high versus low exposure level in individual study if each exposure that had been examined in ≥2 studies. We evaluated the heterogeneity using Cochran's Q test and quantified it by I2 statistic. Publication bias was also evaluated through the funnel plot when sufficient number of studies are available. RESULTS: A total of 11 studies evaluating the association between GDM and exposure to air pollution were identified finally. The summary odds ratio (OR) for incidence of GDM following a 10 µg/m3 increase in PM2.5 exposure during the second trimester was 1.04 (95% Confidence Interval (CI): 1.01, 1.09) and in NOx during the first trimester was 1.03 (95%CI: 1.00, 1.07) per 10 ppb increase, while for high versus low SO2 exposure during the second trimester was 1.25 (95%CI: 1.02, 1.53). High heterogeneity among study-specific results in majority of the analyses were observed, and attributed to different exposure assessment methods, populations, study locations, and covariates adjustment. Publication bias cannot be excluded because of the inclusion of small number of studies. CONCLUSIONS: The present study supports the evidence that air pollution exposure increases the risk the GDM, albeit the existence of high heterogeneity. Further studies are necessary to elaborate the suggestive associations. These results are of public health significance since worsening air pollution in developing countries has been expected to increase the risk of GDM development.

7.
Inflammopharmacology ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31673891

RESUMO

BACKGROUND: Low molecular weight heparin (LMWH) is an anticoagulant that has recently been found benefit in the acute exacerbation stage of chronic obstructive pulmonary disease (COPD). But its efficacy is controversial. The objective of this paper is to compare the harm/benefit of LMWH combined with conventional therapy versus single conventional therapy in the acute exacerbation stage of COPD. METHODS: PubMed, Cochrane Library, EMBASE, CNKI, and Clinical Trials.gov were searched from inception until March 2019. Randomized control trials were included if they reported the use of LMWH for the treatment of COPD. Continuous variable data were reported as mean difference (MD), risk difference (RD), and Peto odds ratio (OR) with corresponding 95% CIs. RESULTS: Twelve RCTs (N = 1086 subjects) were included in the meta-analysis. Pooled results exhibited that LMWH treatment significantly improved the levels of arterial partial pressure of oxygen (PaO2) (MD = 4.58, 95% CI: 1.78-7.39, P = 0.001), forced expiratory volume in 1 s (FEV1) (MD = 0.19, 95% CI: 0.09-0.29, P = 0.0002), and FEV1/forced vital capacity (FVC) (MD = 10.44, 95% CI: 5.40-15.48, P < 0.0001), and significantly reduced the risk of thrombosis (RD, - 0.03; 95% CI, - 0.07 to 0.00; P = 0.05). There was a marginally but nonsignificant improvement in PaCO2 levels vs non-LMWH treatment. Moreover, pooled results exhibited that LMWH may increase the risk of hemorrhage. Subgroup analyses exhibited that LMWH treatment only was associated with a significantly increased risk of minor bleeding but not major hemorrhage. CONCLUSIONS: When compared with single conventional therapy, addition of LMWH to conventional therapy may provide more clinical benefits in the acute exacerbation stage of COPD.

8.
Artigo em Inglês | MEDLINE | ID: mdl-31613777

RESUMO

As the average age of the population goes higher, the people undergo hip arthroplasty surgery to replace their stiff and painful damaged hip joints. To reduce the risk factor after the surgery we developed a visual aided system in previous works. In order to solve the integration problems of commercial camera with other sensors into the femoral head and to minimize the area and power consumption, in this paper we propose a CMOS image sensor of resolution 200x200 specially designed for the application in which each individual pixel measures around 15um x15um in size and the image sensor chip size measures about 3.5mmx3.5mm. The proposed sensor is simulated with the input current variations from 2pA to 100pA for the individual pixels and the corresponding measurements for each pixel ranges from 2mV to 855mV. Besides, we put forward a new method of patterns detection and recognition in the blood covered situation, which provides an accurate segmentation of patterns from the blood. All the detected patterns are recognized by generating its right 9-bit binary ID required for the pose estimation calculation. Furthermore, to reduce system power consumption, we implement algorithms on FPGA to process the image data pixel by pixel and transmit it directly to the computer for post processing. Experimental results show that the patterns detection rate goes as high as 99%, which is 5% better in accuracy compared to the top hat algorithm. Power consumption of the system is 213mW, which is a 70% decrease compared to our previous work.

9.
Anim Biotechnol ; : 1-6, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31645181

RESUMO

The aim of this study was to investigate effects of dietary supplementation of resveratrol on immunity, antioxidative capacity, intestinal barrier function in weaning piglets. Here, fifty-four 28-day-old Duroc × Landrace × Yorkshire weaning piglets were randomly divided into three dietary treatments and fed with a basal diet or a basal diet supplemented with 150 and 300 mg/kg resveratrol, respectively, for 42 days. The results indicated that resveratrol increased serum immunoglobulin G content. In serum, resveratrol increased glutathione peroxidase enzyme activity and decreased malondialdehyde (MDA) content. In liver, resveratrol not only increased T-AOC and total superoxide dismutase enzyme activities but also decreased MDA content. Meanwhile, the results showed that resveratrol had significantly increased the jejunum villus height and villus height/crypt depth, and decreased the crypt depth in jejunum. Furthermore, the mRNA expressions of IL-10 and ZO-1 were significantly increased in jejunal mucosa. However, there was no significant difference in the mRNA expressions of TNF-α, IL-1ß, IL-6, Occludin and Claudin1 between the treatment groups and the control group. Taken together, these results indicated that dietary supplementation of resveratrol could increase antioxidant activity, promote the integrity of intestinal barrier and increase the production of anti-inflammatory cytokines in weaning piglets.

10.
Nat Commun ; 10(1): 4621, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31604910

RESUMO

Tumor subtype-specific metabolic reprogrammers could serve as targets of therapeutic intervention. Here we show that triple-negative breast cancer (TNBC) exhibits a hyper-activated cholesterol-biosynthesis program that is strongly linked to nuclear receptor RORγ, compared to estrogen receptor-positive breast cancer. Genetic and pharmacological inhibition of RORγ reduces tumor cholesterol content and synthesis rate while preserving host cholesterol homeostasis. We demonstrate that RORγ functions as an essential activator of the entire cholesterol-biosynthesis program, dominating SREBP2 via its binding to cholesterol-biosynthesis genes and its facilitation of the recruitment of SREBP2. RORγ inhibition disrupts its association with SREBP2 and reduces chromatin acetylation at cholesterol-biosynthesis gene loci. RORγ antagonists cause tumor regression in patient-derived xenografts and immune-intact models. Their combination with cholesterol-lowering statins elicits superior anti-tumor synergy selectively in TNBC. Together, our study uncovers a master regulator of the cholesterol-biosynthesis program and an attractive target for TNBC.

11.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(10): 987-991, 2019 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-31642432

RESUMO

OBJECTIVE: To investigate the prevalence of obesity and sleep disorders and the association between them among children in Lanzhou, China. METHODS: The stratified cluster random sampling method was used to select 3 283 primary school students in four districts of Lanzhou of Gansu province. Physical examination and sleep questionnaire were conducted to screen out the children who met the criteria for sleep disorders or obesity as subjects. Among the 3 283 children, 200 healthy children without sleep disorders or obesity were enrolled as the control group. RESULTS: The prevalence rate of obesity among the 3 283 children was 5.76% (189/3 283). Among these 189 obese children, 80 (42.3%) had sleep disorders. The prevalence rate of sleep disorders was 16.24% (533/3 283), and the prevalence rate of obesity among the children with sleep disorders was 24.6% (131/533). Snoring was the most common sleep disorder in obese children. The prevalence rate of obstructive sleep apnea hypopnea syndrome was 45% (36/80) among obese children with sleep disorders. The obese children had a significantly higher prevalence rate of sleep disorders than the children with normal body weight [42.3% (80/189) vs 20% (40/200), P<0.01]. CONCLUSIONS: There is a close relationship between obesity and sleep disorders in children in Lanzhou, China.

12.
Chem Commun (Camb) ; 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31642450

RESUMO

A series of dithienylethenes 1a-1d with BF2-doped π-conjugation have been successfully developed. Upon alternating irradiation with green light and red/NIR light, they show efficient photochromism and fluorescence switching behaviors in toluene and PMMA film. Moreover, the fluorescence of 1a can be switched effectively in living cells.

13.
Medicine (Baltimore) ; 98(39): e17295, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574851

RESUMO

BACKGROUND: In this study, investigators will evaluate the efficacy and safety of lactulose for the treatment of irritable bowel syndrome (IBS). METHODS: Literature search for relevant studies up to present will be conducted in MEDICINE, EMBASE, Google Scholar, Web of Science, Cochrane Library, Wangfang, Allied and Complementary Medicine Database, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure. The included studies are randomized controlled trials of lactulose in patients with IBS. We will use RevMan 5.3 software using statistical analysis. RESULTS: This study will provide a high-quality integration of current evidence of lactulose for treating IBS on several aspects including global IBS symptoms, abdominal pain, defecation urgency, stool frequency, stool consistency, quality of life, and adverse events. CONCLUSIONS: This study will provide the evidence for the clinical efficacy and safety of lactulose for the treatment of IBS. PROSPERO REGISTRATION NUMBER: PROSPERO CRD42019140639.


Assuntos
Fármacos Gastrointestinais/uso terapêutico , Síndrome do Intestino Irritável/tratamento farmacológico , Lactulose/uso terapêutico , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Revisão Sistemática como Assunto , Resultado do Tratamento
14.
Langmuir ; 35(43): 13991-13998, 2019 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-31596589

RESUMO

We found that the poly(N-isopropylacrylamide) (PNIPAm) synthesized by free-radical polymerization in organic phase could also form stable microgels in water through solvent exchange without chemical cross-linkers. Dynamic light scattering and transmission electron microscopy showed the larger swelling ratio and higher deformability of these microgels. Nuclear magnetic resonance and infrared spectroscopy indicated that the self-cross-linking structures in these microgels were attributed to the hydrogen atom abstraction both from the isopropyl tert-carbon atoms and the vinyl tert-carbon atoms in PNIPAm chains and the organic solvents were important assistants in the hydrogen abstraction behavior. Our discovery revealed that the self-cross-linking of PNIPAm chains is a common phenomenon within their free-radical polymerization process, whether in aqueous phase or in organic phase. Besides, the addition of second monomers will not affect the cross-linkage of the PNIPAm portion, which may be of great significance for the synthesis of various functional ultralow cross-linking PNIPAm microgels.

15.
Proteins ; 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31589786

RESUMO

Kinesin dimer walks processively along a microtubule (MT) protofilament in a hand-over-hand manner, transiting alternately between one-head-bound (1HB) and two-heads-bound (2HB) states. In 1HB state, one head bound by adenosine diphosphate (ADP) is detached from MT and the other head is bound to MT. Here, using all-atom molecular dynamics simulations we determined the position and orientation of the detached ADP-head relative to the MT-bound head in 1HB state. We showed that in 1HB state when the MT-bound head is in ADP or nucleotide-free state, with its neck linker being undocked, the detached ADP-head and the MT-bound head have the high binding energy, and after adenosine triphosphate (ATP) binds to the MT-bound head, with its neck linker being docked, the binding energy between the two heads is reduced greatly. These results reveal how the kinesin dimer retains 1HB state before ATP binding and how the dimer transits from 1HB to 2HB state after ATP binding. Key residues involved in the head-head interaction in 1HB state were identified.

16.
Int Wound J ; 2019 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-31606950

RESUMO

Pressure injuries (PIs) have now become a common complication of the elderly patients. Some studies have observed that pressure injuries may increase mortality, but this area of evidence has not been evaluated and summarised. The aim of this study was to compare the mortality of patients with pressure injuries and those without pressure injuries. A meta-analysis of observational studies was performed. PubMed, Cochrane Library, Embase, and Web of Science were searched up to April 2019. Studies about mortality among the elderly patients with and without pressure injuries were included. Methodological quality was assessed by the Newcastle-Ottawa Scale (NOS). The fixed effect or random effect model was determined by the test of heterogeneity. The subgroup analysis was performed based on the pressure injuries stages, the region, and the type of study design. The meta-regression analysis was performed to investigate the relationship between the mortality and patients' enrolled year, average age, the incidence of pressure injuries, and gender ratio. The sensitivity analysis was used to explore the impact of an individual study by excluding one at a time. The hazard ratio (HR) and 95% confidence intervals (CIs) in terms of the comparison of two groups were extracted for meta-analysis. A survival curve between two groups by individual patient-level was drew. Eight studies with 5523 elderly patients were included in the analysis. Follow-up periods for the included studies ranged from about 0.5 to 3 years. The elderly patients who complicated with pressure injuries had a higher risk of death. The pooled HR was 1.78 (95% CI 1.46-2.16). A funnel plot showed no publication bias. Further subgroup analysis showed that HR values for the patient stage 3 to 4 pressure injuries (HR:2.41; 95% CI:1.08-5.37) were higher than stage 1-4 and 2-4 pressure injuries (HR: 1.66; 95% CI: 1.35-2.05; HR: 1.74; 95% CI: 1.16-2.60). The meta-regression analysis found that patients' enrolled year, average age, the incidence of pressure injuries, and gender ratio were not the sources of heterogeneity. Sensitivity analyses showed that the outcomes of the study did not change after removing the Onder's article. The survival curve at the individual patient-level also indicated that patients complicated with pressure injuries significantly increased the risk of death (HR: 1.958; 95% CI: 1.79-2.14) in elderly patients. Our meta-analysis indicated that patients complicated with pressure injuries are estimated to have a two times higher risk on mortality compared with patients without pressure injuries during the 3 years follow-up period. Particular attention should be given to the elderly patients who are at higher risk for mortality.

17.
Cell Metab ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31607564

RESUMO

Phosphoglycerate mutase 1 (PGAM1) plays a pivotal role in cancer metabolism and tumor progression via its metabolic activity and interaction with other proteins like α-smooth muscle actin (ACTA2). Allosteric regulation is considered to be an innovative strategy to discover a highly selective and potent inhibitor targeting PGAM1. Here, we identified a novel PGAM1 allosteric inhibitor, HKB99, via structure-based optimization. HKB99 acted to allosterically block conformational change of PGAM1 during catalytic process and PGAM1-ACTA2 interaction. HKB99 suppressed tumor growth and metastasis and overcame erlotinib resistance in non-small-cell lung cancer (NSCLC). Mechanistically, HKB99 enhanced the oxidative stress and altered multiple signaling pathways including the activation of JNK/c-Jun and suppression of AKT and ERK. Collectively, the study highlights the potential of PGAM1 as a therapeutic target in NSCLC and reveals a distinct mechanism by which HKB99 inhibits both metabolic activity and nonmetabolic function of PGAM1 by allosteric regulation.

18.
Development ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31582413

RESUMO

Mutations in the transcription factor GATA2 cause lymphedema. GATA2 is necessary for the development of lymphatic valves (LVs) and lymphovenous valves (LVVs), and for the patterning of lymphatic vessels. Here, we report that GATA2 is not necessary for valvular endothelial cell (VEC) differentiation. Instead, GATA2 is required for VEC maintenance and morphogenesis. GATA2 is also necessary for the expression of cell junction molecules VE-Cadherin and Claudin5 in lymphatic vessels. We identified miR-126 as a target of GATA2, and miR-126 -/- embryos recapitulate the phenotypes of mice lacking GATA2. Primary human lymphatic endothelial cells (HLECs) lacking GATA2 (GATA2 ΔHLEC ) have altered expression of Claudin5 and VE-Cadherin, and blocking miR-126 activity in HLECs phenocopies these changes in expression. Importantly, overexpression of miR-126 in GATA2 ΔHLEC significantly rescues the cell junction defects. Thus, our work defines a new mechanism of GATA2 and uncovers miR-126 as a novel regulator of mammalian lymphatic vascular development.

19.
J Sci Food Agric ; 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31583701

RESUMO

BACKGROUND: Hibiscus sabdariffa is popularly used in daily life, and its extract is widely applied in food and cosmetics. However, it has not been evaluated for its anti-aging effects in academic fields yet. RESULTS: H. sabdariffa calyx aqueous extract (HSCAE) have shown potential activities on collagenase activity suppression, tyrosinase activity inhibition, and anti-oxidation as a free radical scavenger. The current investigation presented that HSCAE was not cytotoxic in skin fibroblasts, and it significantly decreased ultraviolet B (UVB)-induced reactive oxygen species (ROS) on a flow cytometry assay. Moreover, HSCAE reduced matrix metalloproteinase (MMP) expressions, increased tissue inhibitor of metalloproteinase (TIMP)-1 level, and enhanced collagen contents by inhibiting collagenase activity. It also blocked mRNA and protein expressions of melanin production pathway key factors, including microphthalmia-associated transcription factor (MITF), tyrosinase, tyrosinase-related protein-1 (TRP-1) and dopachrome tautomerase-2 (TRP-2). CONCLUSION: These results demonstrated for the first time the potential of HSCAE as a natural antioxidant with the ability to maintain collagen production and to decrease melanin syntheses under UVB radiation, for anti-aging. This article is protected by copyright. All rights reserved.

20.
Eur J Dermatol ; 29(4): 359-365, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31625918

RESUMO

BACKGROUND: Previous reports have shown that epithelial-to-mesenchymal transition (EMT) indicates the importance of transforming growth factor-ß (TGF-ß) signalling in the pathogenesis of systemic sclerosis (SSc). However, the underlying molecular mechanisms of EMT are not fully understood. OBJECTIVES: Brachyury, an evolutionarily conserved transcription factor, was recently identified as an important factor that promotes EMT in human carcinoma cell lines. However, there is no evidence indicating that brachyury is involved in EMT in SSc. MATERIALS AND METHODS: The expression of brachyury and collagen was investigated in cultures of dermal fibroblasts and skin sections derived from SSc patients and healthy controls. Brachyury and collagen expression were determined by immunohistochemistry and immunoblotting, respectively, and mRNA for both was analysed using real-time PCR. RESULTS: Brachyury was overexpressed in SSc dermal fibroblasts both in vivo and in vitro, and this overexpression was inhibited by TGF-ß1 inhibitor. Brachyury siRNA reduced mRNA and protein expression levels of type I collagen in normal and SSc dermal fibroblasts, but did not decrease the levels of major disease-related cytokines. Furthermore, brachyury levels were significantly increased in skin samples of SSc patients relative to healthy controls. CONCLUSIONS: The up-regulation of brachyury in response to activated endogenous TGF-ß signalling may play a role in constitutive up-regulation of collagen in SSc fibroblasts. Further studies assessing the regulatory mechanism of tissue fibrosis induced by brachyury in SSc skin may lead to a better understanding of the pathogenesis, new diagnostic methods, and new therapeutic approaches using siRNAs.

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