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1.
Biomed Pharmacother ; 122: 109760, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31918287

RESUMO

AIMS: Siglec-E, the mouse ortholog of human Siglec-9, is an immunosuppressive cell surface receptor. Both Siglec-E and Siglec-9 are primarily found on neutrophils, macrophages, and monocytes. When Siglec-E binds to sialoglycan ligands in its extracellular environment, it halts the immune cells' inflammatory responses. In the present study, we aimed to investigate expression, mechanisms of action and regulation of Siglec-E ligands during vascular inflammation induced by E. coli lipopolysaccharides (LPS) in mouse aorta. METHODS: The distribution, molecular size and glycoprotein class of Siglec-E ligands on mouse aorta were determined, and the protein carrier of the ligands was identified. In vivo, the expression of Siglec-E ligands was detected after LPS treatment, with or without NF-κB inhibitor administration. In vitro, cultured primary mouse aortic endothelial cells (MAECs) were used to study changes in expression of Siglec-E ligands induced by LPS with or without NF-κB inhibitors. MAECs induced by LPS were co-cultured with macrophages and the effect of increased expression of Siglec-E ligands analyzed. RESULTS: Siglec-E ligands are O-linked sialoglycoproteins with molecular weights of 70-300 kDa and are distributed broadly on mouse aorta as well as on MAECs in vitro. In vivo, the expression of Siglec-E ligands was increased in mice aortas in response to LPS treatment in an NF-κB signaling pathway dependent manner. In MAECs, the expression of Siglec-E ligands was also increased by LPS via an NF-κB signaling pathway. Deleted in malignant brain tumors-1 was identified to be one of multiple protein carriers of Siglec-E ligands, and glycans of ligands involved in MAECs induced by LPS. Notably, co-incubation of macrophages with LPS-treated MAECs induced macrophage apoptosis and decreased macrophage phagocytosis, effects that were completely reversed by blocking Siglec-E binding to Siglec-E ligands. CONCLUSIONS: These data demonstrated that Siglec-E ligands were highly expressed in response to LPS-induced vascular inflammation and inhibited the immune response of macrophages, which may be a therapeutic strategy to interfere with vascular inflammation.

2.
Org Lett ; 22(1): 261-264, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31849229

RESUMO

Two novel [5]helicene derivatives (labeled 5 and 8) have been successfully synthesized and characterized. The structural analyses, photophysical properties, along with density functional theory calculations for unveiling the helicity inversion and equilibrium of the diastereomers, were investigated in a comparative manner. In addition, chemical oxidation of them indicated that molecule 8 exhibited the formation of the radical cation at room temperature.

3.
Adv Mater ; : e1906171, 2019 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-31833134

RESUMO

Pain-perceptual nociceptors (PPN) are essential sensory neurons that recognize harmful stimuli and can empower the human body to react appropriately and perceive precisely unusual or dangerous conditions in the real world. Furthermore, the sensitization-regulated nociceptors (SRN) can greatly assist pain-sensitive human to reduce pain sensation by normalizing hyperexcitable central neural activity. Therefore, the implementation of PPNs and SRNs in hardware using emerging nanoscale devices can greatly improve the efficiency of bionic medical machines by giving them different sensitivities to external stimuli according to different purposes. However, current most-normal organic/oxide transistors face a great challenge due to channel scaling, especially in the sub-10 nm channel technology. Here, a sub-10 nm indium-tin-oxide transistor with an ultrashort vertical channel as low as ≈3 nm, using sodium alginate bio-polymer electrolyte as gate dielectric, is demonstrated. This device can emulate important characteristics of PPN such as pain threshold, memory of prior injury, and pain sensitization/desensitization. Furthermore, the most intriguing character of SRN can be achieved by tuning the channel thickness. The proposed device can open new avenues for the fascinating applications of next-generation neuromorphic brain-like systems, such as bio-inspired electronic skins and humanoid robots.

4.
J Adv Nurs ; 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31840286

RESUMO

AIMS: To explore whether educational information delivered via a medical smartphone app in conjunction with verbal and written instructions, compared with traditional booklet-based and verbal instructions, could improve the quality of bowel preparation for hospitalized patients undergoing colonoscopy. DESIGN: A prospective, single-blinded, randomized controlled trial. METHODS: We performed a prospective, endoscopist-blinded, randomized, controlled trial at Qilu Hospital of Shandong University in China between October 2017 - March 2018. Inpatients eligible based on the inclusion criteria were randomized into two groups. Both groups received oral and written instructions for bowel preparation. In addition, the smartphone app group received instructions through a medical smartphone app. The primary outcome was the rate of adequate bowel preparation according to the Boston bowel preparation scale score. The secondary outcomes included patient compliance with instructions on how to take laxatives, side effects and rates of adenoma detection. RESULTS: A total of 293 patients were enrolled in this study. Demographic characteristics were comparable between the two groups. The χ2 test showed that the medical smartphone app group showed significant improvement in the rate of adequate bowel preparation compared with the control group (77.2% vs. 56.8%, p<.001). The adenoma detection rate was significantly higher in the smartphone app group than in the control group (21.4% vs. 12.8%, p = .029) based on the χ2 test. The rates of incomplete compliance with instructions were 15.17% in the smartphone app group and 33.11% in the control group (p < .001) based on the χ2 test. The overall adverse events were 23.45% and 37.84% in the smartphone app and control groups, respectively (p = .008), based on the χ2 test. CONCLUSION: Instructions provided via a mobile social media app in conjunction with traditional verbal and written methods could improve the quality of bowel preparation, increase the adenoma detection rate and decrease adverse effects. App instructions could be an effective addition to oral and written instructions for inpatients undergoing colonoscopy. IMPACT: This study suggested that clinical personnel could deliver information via smartphone as a powerful addition to traditional educational methods that could improve work efficiency and help patients increase the success rate of bowel preparation.

5.
Nanoscale Res Lett ; 14(1): 362, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31792621

RESUMO

Low-dimensional III-V InAs/GaAs quantum dots (QDs) have been successfully applied to semiconductor saturable absorber mirrors (SESAMs) working at a 900-1310-nm wavelength range for ultrafast pulsed laser applications benefitting from their broad bandwidth, wavelength flexibility, and low saturation fluence. However, it is very challenging to obtain a high-performance QD-SESAM working at the longer wavelength range around 1550 nm due to the huge obstacle to epitaxy growth of the QD structures. In this work, for the first time, it is revealed that, the InAs/GaAs QD system designed for the 1550-nm light emission range, the very weak carrier relaxation process from the capping layers (CLs) to QDs is mainly responsible for the poor emission performance, according to which we have developed a short-period superlattice (In0.20Ga0.80As/In0.30Ga0.70As)5 as the CL for the QDs and has realized ~ 10 times stronger emission at 1550 nm compared with the conventional InGaAs CL. Based on the developed QD structure, high-performance QD-SESAMs have been successfully achieved, exhibiting a very small saturation intensity of 13.7 MW/cm2 and a large nonlinear modulation depth of 1.6 %, simultaneously, which enables the construction of a 1550-nm femtosecond mode-locked fiber lasers with excellent long-term working stability.

6.
Plant Mol Biol ; 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31820284

RESUMO

KEY MESSAGE: The specific and high-level expression of 1Ax1 is determined by different promoter regions. HMW-GS synthesis occurs in aleurone layer cells. Heterologous proteins can be stored in protein bodies. High-molecular-weight glutenin subunit (HMW-GS) is highly expressed in the endosperm of wheat and relative species, where their expression level and allelic variation affect the bread-making quality and nutrient quality of flour. However, the mechanism regulating HMW-GS expression remains elusive. In this study, we analyzed the distribution of cis-acting elements in the 2659-bp promoter region of the HMW-GS gene 1Ax1, which can be divided into five element-enriched regions. Fragments derived from progressive 5' deletions were used to drive GUS gene expression in transgenic wheat, which was confirmed in aleurone layer cells, inner starchy endosperm cells, starchy endosperm transfer cells, and aleurone transfer cells by histochemical staining. The promoter region ranging from - 297 to - 1 was responsible for tissue-specific expression, while fragments from - 1724 to - 618 and from - 618 to - 297 were responsible for high-level expression. Under the control of the 1Ax1 promoter, heterologous protein could be stored in the form of protein bodies in inner starchy endosperm cells, even without a special location signal. Our findings not only deepen our understanding of glutenin expression regulation, trafficking, and accumulation but also provide a strategy for the utilization of wheat endosperm as a bioreactor for the production of nutrients and metabolic products.

7.
Asia Pac J Clin Nutr ; 28(4): 845-856, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31826383

RESUMO

BACKGROUND AND OBJECTIVES: Excessive salt intake is a major public health problem in several countries, especially in China. However, few people are aware of their salt intake. The purpose of this study is to carry out salt intake test in routine physical examination, and to explore the salt intake of different populations and their correlation with diet. METHODS AND STUDY DESIGN: Spot urine sample was collected to test urinary sodium and creatinine excretions for each participant recruited from physical examinations at the Third Xiangya Hospital. The Tanaka formula was used to estimate 24-h urinary sodium excretion, which reflects salt intake. In addition to physical and laboratory examination, information including personal details, health-related habits, and selfreported disease histories was obtained from the National Physical Examination Questionnaire. RESULTS: In total, 26,406 people completed the salt intake evaluation. After data cleansing, the average salt intake was 8.39±1.80 g/d. Male, middle-aged, overweight and obese, hypertensive, and dyslipidaemic populations, as well as those with non-cardiovascular diseases were more likely to have excessive salt intake. Dietary sources had an effect on salt intake. Salt intake was lower in those who consumed more milk and fruit (both p and p trend<0.01) but was higher in those who consumed more lean meat (both p and p trend<0.05), fatty meat (both p and p trend<0.01) and animal organs (both p and p trend<0.01). CONCLUSIONS: The salt intake in this population far surpasses the recommended amount. We strongly recommend salt intake assessment as routine test into physical examination center.

8.
Langmuir ; 2019 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-31800254

RESUMO

Bismuthene, as a new two-dimensional (2D) material made up of diazo metal elements, has drawn massive attention for its unique electronic, mechanical, quantum, and nonlinear optical properties. In recent years, researchers have increasingly turned their attention to the ultrafast photonics fields based on bismuthene. However, the internal ultrashort pulse dynamics has seldom been explored yet. In this work, the nonlinear optical properties of bismuthene nanosheets have been studied and applied in a passively mode-locked fiber laser. The saturation intensity and modulation depth of SA device are about 2.4 MW/cm2 and 1%, respectively. Thanks to the narrow bandgap of bismuthene and tapered fiber structure, a special kind of noise-like multipulses have been obtained. The evolution of the pulsed laser is also studied. This proposed pulsed fiber laser based on bismuthene SA device is well suitable for some applications such as material processing, optical logics etc.

9.
Pharmacogenomics J ; 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31801993

RESUMO

It remains unclear whether the increased risk of new-onset type 2 diabetes (T2D) seen in statin users is due to low LDL-C concentrations, or due to the statin-induced proportional change in LDL-C. In addition, genetic instruments have not been proposed before to examine whether liability to T2D might cause greater proportional statin-induced LDL-C lowering. Using summary-level statistics from the Genomic Investigation of Statin Therapy (GIST, nmax = 40,914) and DIAGRAM (nmax = 159,208) consortia, we found a positive genetic correlation between LDL-C statin response and T2D using LD score regression (rgenetic = 0.36, s.e. = 0.13). However, mendelian randomization analyses did not provide support for statin response having a causal effect on T2D risk (OR 1.00 (95% CI: 0.97, 1.03) per 10% increase in statin response), nor that liability to T2D has a causal effect on statin-induced LDL-C response (0.20% increase in response (95% CI: -0.40, 0.80) per doubling of odds of liability to T2D). Although we found no evidence to suggest that proportional statin response influences T2D risk, a definitive assessment should be made in populations comprised exclusively of statin users, as the presence of nonstatin users in the DIAGRAM dataset may have substantially diluted our effect estimate.

10.
Ann Transl Med ; 7(20): 548, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31807530

RESUMO

Background: Serum lipids have been documented as prognostic biomarkers in several types of cancer, however the prognostic value of serum lipids in non-esophageal squamous cell carcinoma (non-ESCC) is not clear. The purpose of this study was to investigate the prognostic roles of serum lipids in non-ESCC and to establish a novel effective nomogram for overall survival (OS) and disease-free survival (DFS) in patients with non-ESCC. Methods: We retrospectively analyzed the prognostic values of pretreatment serum lipids, including total cholesterol (TC), triglycerides (TG), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), apolipoproteinA-I (ApoAI), and apolipoprotein B (ApoB) and three lipid derivatives: atherogenic index [AI: (TC-HDL-C)/HDL-C], THR (TG/HDL-C) and LHR (LDL-C/HDL-C) in non-ESCC patients. Prognostic factors predictive of OS and DFS were determined by univariate and cox hazards analysis, and prognostic nomograms were established. The predictive power of independent prognostic factors was compared adopting time-dependent ROC. Comparisons between the nomograms and traditional TNM staging systems were evaluated using the C-index and decision curve analysis. Results: A total of 180 non-ESCC patients were recruited in this prospective study between January 2006 and December 2016. Four (cancer type, TNM stage, TC, and TG) and five (cancer type, TNM stage, TC, TG, and LDL-C) independent prognostic factors were chosen to generate the nomogram for OS and DFS, respectively. Our results showed that the area under curves (AUCs) of cancer type and TG were higher than TNM stage for OS. For DFS, however, AUCs of cancer type, TG and LDL-C were higher than the TNM stage. The C-index of the nomogram for predicting the OS was 0.69, which was significantly higher than that of TNM stage (0.58, P=0.005). In addition, for DFS, the C-index of the nomogram was significantly higher than that of the TNM stage (0.70 vs. 0.60, P=0.001). Furthermore, decision curve analysis showed that the predictive accuracy of the prognostic nomogram for OS and DFS were both higher than the TNM stage. Conclusions: Our study demonstrated that pretreatment of serum lipids based on the prognostic nomogram could be applied to predict the OS and DFS in non-ESCC patients.

11.
Artigo em Inglês | MEDLINE | ID: mdl-31808280

RESUMO

Intermolecular charge transport is crucial in π-conjugated materials but the experimental investigation remained challenging. Here, we show that charge transport through intermolecular and intramolecular paths in single-molecule and single-stacking thiophene junctions could be investigated using the mechanically controllable break junction (MCBJ) technique. We found that intermolecular charge transport ability through different single-stacking junctions is approximately independent of molecular structures, which contrasts with the strong length dependence of conductance in single-molecule junctions with the same building blocks, and the dominant charge transport path of molecules with two anchors transits from intramolecular to intermolecular paths when the conjugation pattern increased. The increase of conjugation further leads to higher binding probabilities due to the variation in binding energies supported by density functional theory (DFT) calculations. Our results demonstrate that intermolecular charge transport is not only the limiting step but also provides the efficient and dominate charge transport path at the single-molecule scale.

12.
JAMA Ophthalmol ; 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31855235

RESUMO

Importance: Keratoconus is a condition in which the cornea progressively thins and protrudes in a conical shape, severely affecting refraction and vision. It is a major indication for corneal transplant. To discover new genetic loci associated with keratoconus and better understand the causative mechanism of this disease, we performed a genome-wide association study on patients with keratoconus. Objective: To identify genetic susceptibility regions for keratoconus in the human genome. Design, Setting, and Participants: This study was conducted with data from eye clinics in Australia, the United States, and Northern Ireland. The discovery cohort of individuals with keratoconus and control participants from Australia was genotyped using the Illumina HumanCoreExome single-nucleotide polymorphism array. After quality control and data cleaning, genotypes were imputed against the 1000 Genomes Project reference panel (phase III; version 5), and association analyses were completed using PLINK version 1.90. Single-nucleotide polymorphisms with P < 1.00 × 10-6 were assessed for replication in 3 additional cohorts. Control participants were drawn from the cohorts of the Blue Mountains Eye Study and a previous study of glaucoma. Replication cohorts were from a previous keratoconus genome-wide association study data set from the United States, a cohort of affected and control participants from Australia and Northern Ireland, and a case-control cohort from Victoria, Australia. Data were collected from January 2006 to March 2019. Main Outcomes and Measures: Associations between keratoconus and 6 252 612 genetic variants were estimated using logistic regression after adjusting for ancestry using the first 3 principal components. Results: The discovery cohort included 522 affected individuals and 655 control participants, while the replication cohorts included 818 affected individuals (222 from the United States, 331 from Australia and Northern Ireland, and 265 from Victoria, Australia) and 3858 control participants (2927 from the United States, 229 from Australia and Northern Ireland, and 702 from Victoria, Australia). Two novel loci reached genome-wide significance (defined as P < 5.00 × 10-8), with a P value of 7.46 × 10-9 at rs61876744 in patatin-like phospholipase domain-containing 2 gene (PNPLA2) on chromosome 11 and a P value of 6.35 × 10-12 at rs138380, 2.2 kb upstream of casein kinase I isoform epsilon gene (CSNK1E) on chromosome 22. One additional locus was identified with a P value less than 1.00 × 10-6 in mastermind-like transcriptional coactivator 2 (MAML2) on chromosome 11 (P = 3.91 × 10-7). The novel locus in PNPLA2 reached genome-wide significance in an analysis of all 4 cohorts (P = 2.45 × 10-8). Conclusions and Relevance: In this relatively large keratoconus genome-wide association study, we identified a genome-wide significant locus for keratoconus in the region of PNPLA2 on chromosome 11.

13.
Int Immunopharmacol ; 79: 106109, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31865242

RESUMO

Diabetic ulcers, gangrene, local infections and other traumatic symptoms of wound healing are all directly related. Promoting the early healing of diabetic cutaneous ulcers (DCU) and reducing the disability and treatment costs is an important research project integrating traditional Chinese and Western medicine. Nitric oxide (NO) is a key component of wound healing, and endogenous NO secretion is insufficient during the development of DCU. It has been reported that exogenous NO can promote wound healing, but exogenous NO has a short half-life and is difficult to adhere to the skin. Asiaticoside (AC) is extracted from the traditional Chinese medicine Centella asiatica, and has angiogenic, anticancer, antioxidant, anti-inflammatory, and wound-healing effects. Therefore, our study is based on the hypothesis that the combination of AC and NO to treat DCU is possible. In this study we considered gels of AC and NO, and evaluated the effects of the gel on DCU healing. Based on our study, it was found that the combined effect of asiaticoside and NO could accelerate the healing rate of DCU wounds. The asiaticoside NO gel can inhibit the growth of bacteria in the wound surface, alleviate the inflammatory reaction of wound, and increase the expression of VEGF, iNOS, eNOS and CD34. Our research shows that asiaticoside NO gel may promote DCU wound healing by regulating Wnt/ß-Catenin signaling pathway. It will provide new targets and strategies for the diagnosis and treatment of DCU.

14.
Eur J Radiol ; 123: 108791, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31884189

RESUMO

PURPOSE: To investigate the utility of basi-parallel anatomic scanning magnetic resonance imaging (BPAS-MRI) for the diagnosis of vertebrobasilar artery lesions. METHOD: From October 2017-November 2018, 105 consecutive patients with abnormal configuration of the vertebrobasilar artery on time-of-flight magnetic resonance angiography (TOF-MRA) were enrolled. Conventional high-resolution MRI combined with TOF-MRA were performed to diagnose lesions and were used as the standard for sensitivity and specificity determination. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of BPAS-MRI combined with TOF-MRA were calculated. The consistencies between the two methods were evaluated by kappa test. RESULTS: Of the 105 patients, 45 were diagnosed with arteriosclerosis, 46 with vertebral artery dysplasia, 11 with artery dissection or dissecting aneurysm, and 3 as simple dilatation. Results Compared with conventional high-resolution MRI combined with TOF-MRA, for vertebrobasilar arteriosclerosis, the sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of BPAS-MRI combined with TOF-MRA were 95.6 %, 95.0 %, 93.5 %, 96.6 % and 95.2 %, respectively and kappa value was 0.903. For vertebral artery dysplasia, they were 100 %, 96.6 %, 95.8 %, 100 %, and 98.1 %, respectively and kappa value was 0.961. For vertebrobasilar artery dissection or dissection aneurysm, they were 81.8 %, 96.8 %, 97.8 %, 75.0 % and 95.2 %, respectively and kappa value was 0.756. CONCLUSIONS: BPAS-MRI can show the outer contour of the vertebrobasilar artery system. Combined with TOF-MRA, it may be used to differentiate among vertebrobasilar artery abnormalities, and be used in hospitals where conventional high-resolution MRI is not feasible.

15.
Sci Rep ; 9(1): 19406, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852976

RESUMO

Keratoconus (KC) is the most common corneal ectatic disorder affecting >300,000 people in the US. KC normally has its onset in adolescence, progressively worsening through the third to fourth decades of life. KC patients report significant impaired vision-related quality of life. Genetic factors play an important role in KC pathogenesis. To identify novel genes in familial KC patients, we performed whole exome and genome sequencing in a four-generation family. We identified potential variants in the PPIP5K2 and PCSK1 genes. Using in vitro cellular model and in vivo gene-trap mouse model, we found critical evidence to support the role of PPIP5K2 in normal corneal function and KC pathogenesis. The gene-trap mouse showed irregular corneal surfaces and pathological corneal thinning resembling KC. For the first time, we have integrated corneal tomography and pachymetry mapping into characterization of mouse corneal phenotypes which could be widely implemented in basic and translational research for KC diagnosis and therapy in the future.

16.
Mol Ther Nucleic Acids ; 18: 681-695, 2019 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-31707205

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia and cannot be cured. The etiology and pathogenesis of AD is still not fully understood, the genetics is considered to be one of the most important factors for AD onset, and the identified susceptible genes could provide clues to the AD mechanism and also be the potential targets. MicroRNA-146a-5p (miR-146a) is well known in the regulation of the inflammatory response, and the functional SNP of miR-146a was associated with AD risk. In this study, using a noninvasive nasal administration, we discovered that a miR-146a agomir (M146AG) rescued cognitive impairment in the APP/PS1 transgenic mouse and alleviated the overall pathological process in the AD mouse model, including neuroinflammation, glia activation, Aß deposit, and tau phosphorylation in hippocampi. Furthermore, the transcriptional analysis revealed that besides the effect of neuroinflammation, M146AG may serve as a multi-potency target for intervention in AD. In addition, Srsf6 was identified as a target of miR-146a, which may play a role in AD progression. In conclusion, our study supports that the nasal-to-brain pathway is efficient and operable for the brain administration of microRNAs (miRNAs), and that miR-146a may be a new potential target for AD treatment.

17.
Front Chem ; 7: 715, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31709238

RESUMO

Gold nanorods (GNRs) has been investigated in the field of chemistry, optoelectronics, and medicine for their tenability, compatibility, electromagnetics, and excellent photonics properties. Especially, GNRs, used to generate ultrashort pulse, have been studied recently. However, multiple pulses evolution based on GNRs needs to be further explored. In this article, GNRs are synthesized by seed-mediated growth method, characterized systematically and been chosen as saturable absorber (SA) to apply in ultrafast photonics. The GNRs SA presents a saturable intensity of 266 MW/cm2, modulation depth of 0.6%, and non-saturable loss of 51%. Furthermore, a passively mode-locked erbium-doped fiber laser based on GNRs SA with femtosecond pulse is demonstrated. Thanks to the excellent properties of GNRs, by adjusting the cavity polarization direction with the proposed GNRs SA, soliton molecules operation with spectrum modulation period of 3.3 nm and pulse modulation interval of 2.238 ps is directly obtained. For the most important, 9th-order harmonic soliton molecules have been generated in the laser cavity for the first time. It is demonstrated that GNRs can be a novel type of non-linear optical (NLO) device and have potential applications in the field of ultrafast photonics.

18.
J Biol Chem ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31712309

RESUMO

Bone morphogenetic protein 10 (BMP10) is a cardiac peptide growth factor, belonging to the transforming growth factor beta (TGFß) superfamily, that critically controls cardiovascular development, growth, and maturation. It has been shown that BMP10 elicits its intracellular signaling through a receptor complex of activin receptor-like kinase 1 (ALK1) with morphogenetic protein receptor type II (BMPR2A) or activin receptor type-2A (ActR2A). Previously, we generated and characterized a transgenic mouse line expressing BMP10 from the α-myosin heavy chain gene promoter (αMHC-Bmp10), and found that these mice have normal cardiac hypertrophic responses to both physiological and pathological stimuli. In this study, we report that these transgenic mice exhibit significantly reduced levels of cardiomyocyte apoptosis and cardiac fibrosis in response to a prolonged administration of the ß-adrenoceptor agonist isoproterenol (ISO). We further confirmed this cardioprotective function with a newly generated conditional Bmp10 transgenic mouse line, in which Bmp10 was activated in adult hearts by tamoxifen. Moreover, the intraperitoneal administration of recombinant human BMP10 (rhBMP10) was found to effectively protect hearts from injury, suggesting potential therapeutic utility of using BMP10 to prevent heart failure. Gene profiling and biochemical analyses indicated that BMP10 activates the SMAD-mediated canonical pathway and, unexpectedly, also the signal transducer and activator of transcription 3 (STAT3)-mediated signaling pathway both in vivo and in vitro. Additional findings further supported the notion that BMP10's cardioprotective function likely is due to its dual activation of SMAD- and STAT3-regulated signaling pathways, promoting cardiomyocyte survival and suppressing cardiac fibrosis.

19.
Plant Physiol Biochem ; 145: 174-183, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31704591

RESUMO

Drought significantly affects plant growth and has devastating effects on crop production, NAC transcription factors respond to abiotic stresses by activating gene expression. In this study, a maize NAC transcription factor, ZmNAC33, was cloned and characterized its function in Arabidopsis. Transient transformation in Arabidopsis leaves mesophyll protoplasts and trans-activation assays in yeast showed that ZmNAC33 was localized in the nucleus and had transactivation activity. qRT-PCR analysis showed that ZmNAC33 in maize was induced by drought, high salinity and abscisic acid (ABA) stress. Promoter analysis identified multiple stress-related cis-acting elements in the promoter region of ZmNAC33. In ZmNAC33 transgenic Arabidopsis, germination rates were higher than in wild type plants under ABA and osmotic stress at the germination stage, and overexpression lines exhibited higher survival rates and higher antioxidant enzyme activities compared with wild type under drought stress. These results indicate that ZmNAC33 actes as a positive regulator in drought tolerance in plants.

20.
Nanoscale ; 11(46): 22539-22549, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31746897

RESUMO

Dielectric composites constructed using carbon and metal oxides have become a hot research topic; however, the strategy to strengthen the coupling of components still needs to be optimized to enhance dielectric loss. Herein, ultra-fine ZnO derived from ZIF-8 was uniformly distributed and tightly embedded in multi-wall carbon nanotubes (C-ZnO@CNTs) via a novel confined space synthesis. Due to the presence of a polypyrrole coating, ZnO nanocrystals could be formed in the space of the original polyhedron and inserted into the CNTs, promoting the generation of polarized CNTs and providing abundant polarization centers on the CNTs. The composites exhibited superior microwave absorption capacity with a reflection loss value of up to -48.2 dB at 6.0 GHz, and the effective bandwidth reached 14.9 GHz by adjusting their thickness. According to the geometric phase analysis, the strain driven by the tight-coupling between ZnO-CNTs was confirmed to exist in the interfaces, boosting their inherent electromagnetic properties. The improved dielectric loss was caused by the strong interfacial polarization among ZnO-ZnO or ZnO-CNTs and the conductive loss among intertwined CNTs network, as revealed by electron holography. Therefore, the overall electrical properties could be improved by the polarized C-ZnO@CNTs with high electron conductivity. The confined space strategy may have promising potential for the synthesis of new composites of polarized carbon materials tightly coupled with metal oxides nanocrystals.

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