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1.
Food Chem ; 303: 125380, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31445175

RESUMO

Soybean Bowman-Birk trypsin inhibitor (BBTI), an antinutritional factor of soy products, could strongly inhibit the protein digestion. The inactivation effect and mechanism of BBTI induced by tea polyphenols (TPs) and its major components (EGCG and EGC), were investigated in this study using fluorescence, FTIR, CD spectroscopy, isothermal titration calorimetry (ITC) and molecular docking. EGCG and EGC interacted with BBTI via static quenching process and hydrophobic interaction, with binding constant (Ka) of 2.19 × 103 M-1 and 0.25 × 103 M-1 at 298 K, respectively. TPs, EGCG and EGC induced a transition of BBTI conformation from disorder to order. ITC analysis and molecular docking revealed the interaction of EGCG-BBTI and EGC-BBTI were spontaneous, and hydrophobic interactions and hydrogen bonds were the predominant forces. Overall, this study clearly suggested that EGCG could be a promising inactivating agent for BBTI, which could also improve the safety and nutritional value of soy products.

2.
Vet Microbiol ; 237: 108397, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31585638

RESUMO

Aves polyomavirus 1 (APV) causes inflammatory disease in psittacine birds, especially in young budgerigar. In this study, an APV virus (SD18 strain) was isolated from a diseased psittacine birds breeding facility. The full genome (4981 bp) of SD18 was determined and analyzed. Phylogenetic analysis of full genome sequences indicated all the APV strains form two groups. The SD18 strain showed close relationship with APV isolated from Poland, however, the other Chinese strains are located in group II, which suggested different genotypes APVs are co-circulating in China. Compared with the consensus sequence of APV full genome, the SD18 strain contains 13 nucleotide mutations, and 2 unique amino acid substitutions (R179M and Q382K) located in VP2/3 and Large T proteins. To explore the pathogenicity of the virus, the SD18 strain was used to challenge 2-week-old budgerigars. All infected birds died no later than 5 days post infection, and virus was detected in multiple organs including brain, heart, ingluvies, liver, and intestine, which indicated that SD18 is fatal and causes systemic infection in young budgerigar. In vitro studies showed that SD18 replicated efficiently in CEF cells and reached the highest viral titers at 9 days post infection. Notably, replication of SD18 stimulated IFN-ß response in CEF cells and overexpression of the VP4 or VP4Delta proteins significantly inhibited IFN-ß promoter activation, which could be the strategy of APV to escape from the host innate immunity.

3.
Medicine (Baltimore) ; 98(41): e17539, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31593131

RESUMO

Research on the relationship between iodine intake and thyroid cancer (TC) risk is limited, and the findings are inconclusive. The objective of this study was to provide emerging evidence for the association between iodine intake and TC risk in a Chinese population.An ecological study of epidemiology is used to compare the iodine intake among populations with different TC incidence in Zhoushan, China. Incidence rates of TC were investigated and compared among four counties of the Zhoushan Islands from 2014 to 2018. Iodized salt consumption rate and the level of urinary iodine concentration (UIC) were analyzed for pupils and pregnant women from four counties.During 2014 to 2018, a total of 2495 new cases of TC were diagnosed in Zhoushan Islands. The mean crude incidence rate of TC was 51.29 per 100,000 inhabitants, and the standardized (world population) incidence rate (SIR) was 31.34 per 100,000 population. Incidence rates (SIR and crude incidence rates) were significantly higher in women than in men (χ test, P < .05). Both male and female, the incidence of TC in Daishan County is higher than the other three counties of Zhoushan. Iodized salt consumption rate and median UIC in pupils and pregnant women in Daishan County was significantly lower than the other three counties (χ test and Kruskal-Wallis test, all P < .05). The population with high TC incidence has a lower iodized salt consumption and a lower level of UIC compare with the relative low TC incidence populations.The low consumption of iodized salt with mild iodine deficiency may contribute to explain the exceptionally high incidence of TC in Daishan County. Further subtle designed studies are needed to provide additional insights into the epidemiology and etiology of TC and help identify the safe limit of iodine intake for prevention.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31582220

RESUMO

Because of the advantages of induced pluripotent stem cells (iPSCs), iPSCs-derived keratinocyte hold great clinical and research potential in wound repair. Similar to other cell transplantation therapies, the migration ability of iPSCs-derived keratinocyte transplanted into skin is critical to the therapeutic effect. Hsp90α had a positive effect on migration of keratinocytes. Therefore, the aim of this study was to investigate the effects of Hsp90α on transplanted iPSCs-derived keratinocyte in a skin model of deep second degree burns. First, keratinocytes were differentiated from iPSCs by treating with RA and BMP4. Next, we explained the effect Hsp90α on iPSCs-derived keratinocyte in vitro. We found that hsp90α promoted cell migration of iPSCs-derived keratinocyte. Furthermore, activation of AKT was required for Hsp90α-induced iPSCs-derived keratinocyte migration. Then PBS, Hsp90α, iPSCs-derived keratinocyte, and iPSCs-derived keratinocyte plus Hsp90α were applied to the wound bed of deep second degree burns. Wound healing was assessed by gross evaluation and hematoxylin and eosin staining. Our results shown that wound treated with iPSCs-derived keratinocyte plus Hsp90α significantly accelerates the rate of wound healing closure than other groups. In addition, the number of CFSE-labeled iPSCs-derived keratinocyte in regenerated epidermis was increased in iPSCs-derived keratinocyte plus Hsp90α group. In summary, these findings represent that combined administration of iPSCs-derived keratinocyte and Hsp90α may be a promising therapeutic strategy for wound healing.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31590161

RESUMO

Single-crystalline FeTe2 in marcasite phase with orthorhombic structure was prepared via chemical vapor transport. Cooling FeTe2 single crystals from room temperature down to 2K, multiple magnetic phase transitions were observed. Paramagnetic (PM) to antiferromagnetic (AFM) and then to ferromagnetic (FM) occurred at 85K and 38K for in-plane, 73K and 29K for out-of-plane, respectively. A strong uniaxial magnetic anisotropy was found due to FeTe6 octahedron distortion and structural modulation in FM region. The novel negative volume expansion (NVE) initiated in the vicinity of AFM to FM transition. An abrupt frequency shift of the most intense mode at 118 cm-1 and evolution of the Te-Te stretching mode near 40K, corresponding to the phase transition from AFM to FM were observed. The temperature-dependent resistance revealed an anomaly (semiconductor to metallic transition) around AFM-FM transition, which can easily be suppressed and move to high temperature by the applied magnetic field. The results from XRD, Raman and resistivity indicated that the structural parameters, vibration frequency and transport are sensitive to the phase transition from AFM to FM. The nature of direct band gap with 0.67 eV was identified through UV-Vis-NIR spectrum of FeTe2 single crystals at room temperature.

6.
Biomed Pharmacother ; 120: 109475, 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31580970

RESUMO

BACKGROUND: Doxorubicin (DOX) is an anticancer drug that has been widely used in the clinic. However, recently its application has been limited due to the cardiotoxic effects it has caused. Severe cardiotoxicity of DOX causes cardiac hypertrophy that may lead to heart failure. It has previously been demonstrated that CACNA1H is re-expressed in hypertrophic cardiomyocytes. In this study, we aimed to investigate the role of CACNA1H in DOX-induced acute cardiotoxicity, and to investigate its possible underlying mechanisms of action involved. METHODS: Firstly, DOX-induced cardiac injury and changes in the expression of CACNA1H were evaluated. We explored the role of endoplasmic reticulum (ER) stress and apoptosis in mice that underwent DOX-induced cardiac injury. Next, to explore the role of CACNA1H in this process, we evaluated the changes in DOX-induced cardiac injury and ER stress after treatment with the CACNA1H specific inhibitor ABT-639. Next, we used ER stress inhibitor UR906 to verify the role of ER stress in DOX induced cardiotoxicity in H9C2 cells. RESULTS: DOX-treatment caused acute heart injury, leading to a decrease in cardiac function in mice, an increase in apoptosis of cardiac myocytes, and a significant increase in the expression level of CACNA1H in heart tissue. Next, mice were treated with CACNA1H inhibitor ABT-639 and we demonstrated that it partly protects myocardial function and reduces myocardial cell apoptosis. In addition, our data indicated that CACNA1H may play a role in alleviating DOX-induced cardiotoxicity by reducing the severity of ER stress because the use of ABT-639 significantly changed ER stress-related proteins, including p-PERK, PERK, CHOP, GRP78, ATF6, and ATF4. Furthermore, we found that the use of ER stress inhibitor UR906 in H9C2 cells significantly alleviated the increased expression of ER stress related proteins and apoptosis related proteins caused by DOX, and meanwhile reduced the degree of intracellular oxidative stress and intracellular calcium ion concentration. CONCLUSION: CACNA1H inhibitors significantly alleviated DOX-induced cardiotoxicity and apoptosis induced by ER stress.

7.
Food Funct ; 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31602443

RESUMO

The objective of this study was to investigate the effects of dietary intervention on intestinal microbiota-mediated change in short chain fatty acid (SCFA) profile and intestinal homeostasis. Sequencing of the 16S rDNA of gut bacteria, metagenomics, intestinal epithelial transcriptomics, and metabonomics were conducted. Results showed that the dietary interventions altered the microbiota composition of cecal digesta, microbiota-mediated metabolism, and the gene expression profile in intestinal epithelial cells. Compared with red meat-diet-fed mice, fiber-diet-fed mice presented a shift in the gut microbiome toward increased production of butanoate, which was accompanied by up-regulation of microbiota- and AMP-activated protein kinase (AMPK)-dependent gene expression and decrease in serum concentrations of trimethylamine N-oxide (TMAO), triglyceride (TG) and glucose (GLU). The results suggested a new regulatory mechanism via which butanoate and AMPK activation contributed to intestinal integrity and homeostasis by affecting metabolism, intestinal barrier function and transporter expression.

8.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3608-3614, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31602930

RESUMO

In order to provide scientific basics for exploitation and sufficient application of Polyporus umbellatus resources and study the monosaccharide composition of P. umbellatus polysaccharides,the anthrone-sulfuric acid method was applied to compare polysaccharide content of P. umbellatus from 17 producing areas. The monosaccharides were derived by 1-phenyl-3-methyl-5-pyrazolone( PMP) and the derivatives were identified by UPLC-MS/MS and the content of each monosaccharide component was determined simultaneously. The results demonstrated that there was a certain difference in total polysaccharide content of P. umbellatus from different regions,and the content of total P. umbellatus polysaccharide from Shaanxi province and Sichuan province( 1. 15% and 1. 90%) was relatively higher than that of others areas. Polysaccharides from P. umbellatus was mainly composed of eight monosaccharides,including glucose,glucuronic acid,galactose,ribose,xylose,arabinose,mannose and fucose. The contents of glucose( 17. 65 mg·g-1) was higher than others. The ribose was the lowest( 0. 13 mg·g-1). In addition,fructose,rhamnose and galacturonic acid were also detected in some samples. Furthermore,the results of cluster analysis( CA) and principal component analysis( PCA) indicated that totally 17 batches of P. umbellatus polysaccharide could be classified into three clusters,samples collected from Wuchang in Heilongjiang province were clustered into one group separately. The study can provide a basis for rational utilization of P. umbellatus resources,and also implies the sequence of monosaccharide linking and pharmacological activity of P. umbellatus polysaccharides.

9.
J Zhejiang Univ Sci B ; 20(11): 940-944, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31595731

RESUMO

Common bile duct (CBD) stones are a frequent problem in Chinese populations, and their incidence is particularly high in certain areas (Wang et al., 2013). In recent years, laparoscopic common bile duct exploration (LCBDE) and endoscopic retrograde cholangiopancreatography (ERCP) have been the main surgical procedures for CBD stones, although each has different advantages and disadvantages in the treatment of choledocholithiasis (Loor et al., 2017; Zhou et al., 2017). For patients with large stones, a dilated CBD, especially concurrent gallstones, LCBDE is the preferred and most economical minimally invasive procedure (Koc et al., 2013). However, a T-tube is often placed during LCBDE to prevent postoperative bile leakage; this is associated with problems such as bile loss, electrolyte disturbance, and decreased gastric intake (Martin et al., 1998). In addition, the T-tube usually must remain in place for more than a month, during which time the patient's quality of life is seriously compromised. Many skilled surgeons currently perform primary closure of the CBD following LCBDE, which effectively speeds up rehabilitation (Hua et al., 2015). However, even in sophisticated medical centers, the incidence of postoperative bile leakage still reaches ≥10% (Liu et al., 2017). Especially for a beginner, bile leakage remains a key problem (Kemp Bohan et al., 2017). Therefore, a safe and effective minimally invasive surgical approach to preventing bile leakage during primary closure of the CBD after LCBDE is still urgently needed.

10.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(8): 911-915, 2019 Aug 28.
Artigo em Chinês | MEDLINE | ID: mdl-31570679

RESUMO

OBJECTIVE: To evaluate the safety and efficacy of endoscopic balloon dilation (EBD) and endoscopic stricturotomy with needle knife (NKSt) in patients with inflammatory bowel diseases (IBD)-relevant strictures. 
 Methods: From July 2015 to September 2018, 14 patients undergoing double balloon-enteroscopy at the Third Xiangya Hospital of Central South University were enrolled. There was a total of 16 lesions. Endoscopic intervention was performed for 16 times. EBD was done for 11 times, and 5 stricturotomies were carried out. Regular follow-up and examinations were done to observe whether there was remission or recurrence of clinical symptoms and replacement surgery.
 Results: All 14 patients were successfully treated by endoscopy, and the success rate was 100%. Postoperative clinical symptoms were alleviated, and serious complications, such as perforation or hemorrhaging, did not occur. Obstructive symptoms were effectively alleviated at a median follow-up of 26.1 months (5.9-35.3 months) and 8.3 months (1.6-17.8 months) for patients with balloon dilatation and stricturotomy, respectively. Two patients presented with symptoms of obstruction. These were given conservative symptomatic treatment without surgical intervention.
 Conclusion: Enteroscopic treatments (EBD and NKSt) are safe and effective for intestinal strictures, and can prolong the time before surgical intervention is needed.

11.
Stem Cell Res Ther ; 10(1): 298, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547887

RESUMO

BACKGROUND: Although tissue-engineered cartilage has been broadly studied, complete integration of regenerated cartilage with residual cartilage is still difficult for the inferior mechanical and biochemical feature of neocartilage. Chondrogenesis of mesenchymal stem cells can be induced by biophysical and biochemical factors. METHODS: In this study, autologous platelet-rich fibrin (PRF) membrane was used as a growth factor-rich scaffold that may facilitate differentiation of the transplanted bone marrow mesenchymal stem cells (BMSCs). At the same time, hydrostatic pressure was adopted for pre-adjustment of the seed cells before transplantation that may promote the mechanical flexibility of neocartilage. RESULTS: An in vitro study showed that the feasible hydrostatic pressure stimulation substantially promoted the chondrogenic potential of in vitro-cultured BMSC/PRF construct. In vivo results revealed that at every time point, the newborn tissues were the most favorable in the pressure-pretreated BMSC/PRF transplant group. Besides, the transplantation of feasible hydrostatic pressure-pretreated construct by BMSC sheet fragments and PRF granules could obviously improve the integration between the regenerated cartilage and host cartilage milieu, and thereby achieve boundaryless repair between the neocartilage and residual host cartilage tissue in rabbit temporomandibular joints. It could be concluded that feasible hydrostatic pressure may effectively promote the proliferation and chondrogenic differentiation of BMSCs in a BMSC/PRF construct. CONCLUSION: This newly formed construct with biomechanical flexibility showed a superior capacity for cartilage regeneration by promoting the mechanical properties and integration of neocartilage.

12.
Sensors (Basel) ; 19(18)2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31487831

RESUMO

An algorithm correcting distortion based on estimating the pixel shift is proposed for the degradation caused by underwater turbulence. The distorted image is restored and reconstructed by reference frame selection and two-dimensional pixel registration. A support vector machine-based kernel correlation filtering algorithm is proposed and applied to improve the speed and efficiency of the correction algorithm. In order to validate the algorithm, laboratory experiments on a controlled simulation system of turbulent water and field experiments in rivers and oceans are carried out, and the experimental results are compared with traditional, theoretical model-based and particle image velocimetry-based restoration and reconstruction algorithms. Using subjective visual evaluation, image distortion has been effectively suppressed; based on an objective performance statistical analysis, the measured values are better than the traditional and formerly studied restoration and reconstruction algorithms. The method proposed in this paper is also much faster than the other algorithms. It can be concluded that the proposed algorithm can effectively improve the de-distortion effect of the underwater turbulence degraded image, and provide potential techniques for the accurate operation of underwater target detection in real time.

13.
Clin Cardiol ; 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31509267

RESUMO

BACKGROUND: For patients with acute myocardial infarction (AMI) complicated by cardiogenic shock (CS) undergoing primary percutaneous coronary intervention (PCI), the optimal timing of the initiation of intra-aortic balloon pump (IABP) therapy remains unclear. Therefore, we performed the first meta-analysis to compare the outcomes of IABP insertion before vs after primary PCI in this population. METHODS: Electronic databases of PubMed, EMBASE, and Cochrane Library were comprehensively searched from inception to April 1, 2019, to identify the eligible studies. The main outcomes were short-term (in-hospital or 30 days) and long-term (≥ 6 months) mortality. In addition, pooled analysis of risk-adjusted data were also performed to control for confounding factors. RESULTS: Seven observational studies and two sub-analysis of randomized controlled trials involving 1348 patients were included. Compared to patients inserted IABP after PCI, patients who received IABP therapy before primary PCI had similar risks of short-term (odds ratio [OR] 0.88, 95% CI 0.49 to 1.59) and long-term (OR 0.99, 95% CI 0.58 to 1.68) all-cause mortality. Moreover, a pooled analysis of risk-adjusted data also found similar effects of the two therapies on short-term (OR 0.65, 95% CI 0.34 to 1.25) and long-term (OR 0.68, 95% CI 0.17 to 2.72) mortality. Besides, no significant difference was found between the two groups with respect to reinfarction, repeat revascularization, stroke, renal failure, and major bleeding. CONCLUSIONS: The timing of the initiation of IABP therapy does not appear to impact short-term and long-term survival in patients with AMI complicated by CS undergoing primary PCI.

14.
ChemSusChem ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498955

RESUMO

Lead halide perovskite (LHP) nanocrystals have been actively pursued as catalysts in photocatalytic fields most recently, owing to their inexpensive fabrication techniques and excellent optoelectronic properties. However, LHP nanocrystals have never been used for artificial photosynthesis in aqueous solution due to their high sensitivity to water. Herein, for the first time, water-tolerant cobalt doped CsPbBr3/Cs4PbBr6 nanocrystals are successfully prepared with the protection of hexafluorobutyl methacrylate, which can be employed as efficient photocatalysts for visible-light-driven CO2 reduction in pure water. The perovskite nanocrystals with 2% cobalt doping exhibit impressive yield of 247 µmol g-1 for photocatalytic CO2 conversion to CO and CH4, using water as an electron source. Our study makes a great step for practical artificial photosynthesis using LHP nanocrystals as photocatalysts in aqueous solution.

15.
Front Immunol ; 10: 2050, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552021

RESUMO

The transcription factor Bach2 is a susceptible gene for numerous autoimmune diseases including systemic lupus erythematosus (SLE). Bach2 -/- mice can develop a lupus-like autoimmune disease. However, the exact cellular and molecular mechanisms via which Bach2 protects the hosts from developing autoimmunity remains incompletely understood. Here, we report that Bach2 ablation on T cells, but not B cells, resulted in humoral autoimmunity, and this was associated with expansion of T follicular helper (Tfh) cells and abnormal germinal centers. Bach2 was down-regulated in Tfh cells and directly suppressed by the Tfh-defining transcription factor BCL6. Mechanistically, Bach2 directly suppresses the transcription of Cxcr5 and c-Maf, two key regulators of Tfh cell differentiation. Bach2-deficient Tfh cells were skewed toward the IL-4-producing subset, which induced IgG1 and IgE isotype switching of B cells. Heterozygous Bcl6 deficiency reduced the formation of germinal center and autoantibodies, and ameliorated the pathology in Bach2-deficient mice. Our findings identify Bach2 as a crucial negative regulator of Tfh cells at steady state and prove that Bach2 controls autoimmunity in part by restraining accumulation of pathogenic Tfh cells.

17.
BMJ Open ; 9(9): e023586, 2019 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-31530585

RESUMO

RESEARCH QUESTION: The current population-based study aimed to investigate the prevalence of diabetic retinopathy (DR) and risk factors among residents over 40 years old in the rural area of Dongguan, southern China. STUDY DESIGN: The Dongguan Eye Study was a population-based study from September 2011 to February 2012. SETTING: The area was set in the rural area of Dongguan, southern China. PARTICIPANTS: Adult rural population aged 40 or older. INTERVENTION: Participants underwent haematological, physical, ophthalmic examinations and completed a questionnaire regarding lifestyles and systemic medical conditions. PRIMARY AND SECONDARY OUTCOME MEASURES: The frequency and risk factors of visual impairment and the major vision-threatening eye diseases. RESULTS: Of the 8952 Han Chinese, 1500 were diagnosed with type 2 diabetes mellitus (T2DM) with an average age of 59.5±11.1 years, and 1310 participants with fundus photography results were analysed. Standardised prevalence rate of DR was 18.2% for all patients with diabetes, 32.8% for the patients with previously diagnosed diabetes and 12.6% for newly diagnosed patients with T2DM. The prevalence rate of male DR was significantly higher than that of female DR (23.0% vs 14.1%, p<0.001). No significant difference was found in age-specific prevalence of DR. In diabetic patients, the prevalence rates of vision-threatening diabetic retinopathy, diabetic macular oedema and clinically significant macular oedema were 2.5%, 2.8% and 0.9%, respectively. Male gender, higher education level, longer duration of diabetes mellitus (DM), higher systolic blood pressure and glycosylated haemoglobin were independent risk factors for DR development in patients with diabetes. CONCLUSION: A relatively lower prevalence of DR was found among the participants with T2DM in residents over 40 years in the rural area of southern China. Thus, an ophthalmic examination is recommended, especially for individuals with DM and DR risk factors. There is a need to increase awareness and education on DM and DR, especially in subjects with DR risk factors to reduce the incidence of DR and macular oedema.

18.
Chem Commun (Camb) ; 55(76): 11370-11373, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31478549

RESUMO

We demonstrated a novel single molecule - tetrakis(4-carboxyphenyl) porphyrin (TCPP) with a large π-conjugated system as a high-performance organic anode of lithium batteries. It was found that this TCPP displayed relatively low solubility (<0.1 mg mL-1) in a 1 M LiDFOB/PC electrolyte, high reversible specific capacity (ca. 1200 mA h g-1 at 358 mA g-1), excellent rate capability (548.4 mA h g-1 at 8 A g-1) and superior cycling performance (capacity retention of 89% after 2500 cycles at 6 A g-1).

19.
Atherosclerosis ; 289: 143-161, 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31518965

RESUMO

BACKGROUND AND AIMS: Krüppel-like factor 14 (KLF14) is known to play a role in atherosclerosis, but the underlying mechanisms are still largely unknown. The aim of our study was to explore the effects of KLF14 on lipid metabolism and inflammatory response, providing a potential target for lowering the risk of atherosclerosis-causing disease. METHODS AND RESULTS: mRNA and protein levels of KLF14 were significantly decreased in oxidized low-density lipoprotein (oxLDL)-treated macrophages and in the atherosclerotic lesion area. Chromatin immunoprecipitation (ChIP) and luciferase reporter gene assays were used to confirm that KLF14 positively regulated miR-27a expression by binding to its promoter. We also found that KLF14 could restored appropriate cellular lipid homeostasis and inflammatory responses via negatively regulating lipoprotein lipase (LPL) expression in THP1-derived macrophages through miR-27a. In addition, gypenosides (GP), a KLF14 activator, delayed the development of atherosclerosis in apolipoprotein E deficient (apoE-/-) mice. CONCLUSIONS: KLF14 plays an antiatherogenic role via the miR-27a-dependent down-regulation of LPL and subsequent inhibition of proinflammatory cytokine secretion and lipid accumulation.

20.
J Am Chem Soc ; 141(40): 15879-15883, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31490067

RESUMO

We have investigated the mechanical dissociation of an ammonium/crown ether rotaxane using experimental (sonication) and computational (CoGEF) methods and found that it breaks faster than its noninterlocked or uncoupled interlocked (i.e., pulled from both sides of the axle) counterparts. This was confirmed by the analysis of the fragments, which are the results of a selective unstoppering reaction. Interestingly, the initial dissociation also triggered the elimination of the axle segment separating the stopper from the ammonium binding station. CoGEF calculations have shown that the constriction of the axle by the macrocycle during the elongation of the rotaxane provokes the accumulation of tensile and torsional stress that ultimately leads to the rupture of a covalent bond in the constricted section of the axle. Overall, these results suggest that the rotaxane architecture acts as a lever that accelerates the dissociation of interlocked covalent bonds. This phenomenon could impact the mechanical properties of slide-ring materials at high strain.

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