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1.
J Pharm Biomed Anal ; 177: 112813, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31472326

RESUMO

Differentiated composition in precursor ions for different subclasses of ginsenosides in the negative electrospray-ionization mode has been reported, which lays a foundation for the sorted and untargeted identification of ginsenosides. Carboxyl-free ginsenosides simultaneously from Panax ginseng, P. quinquefolius, and P. notoginseng, were comprehensively characterized and statistically compared. A neutral loss/product ion scan (NL-PIS) incorporated untargeted profiling approach, coupled to ultra-high performance liquid chromatography, was developed on a linear ion-trap/Orbitrap mass spectrometer for characterizing carboxyl-free ginsenosides. It incorporated in-source fragmentation (ISF) full scan-MS1, mass tag-MS2, and product ion scan-MS3. Sixty batches of ginseng samples were analyzed by metabolomics workflows for the discovery of ginsenoside markers. Using formic acid (FA) as the additive, carboxyl-free ginsenosides (protopanaxadiol-type, protopanaxatriol-type, and octillol-type) gave predominant FA-adducts, while rich deprotonated molecules were observed for carboxyl-containing ginsenosides (oleanolic acid-type and malonylated) when source-induced dissociation (SID) was set at 0 V. Based on the NL transition [M+FA‒H]- > [M-H]- and the characteristic sapogenin product ions, a NL-PIS approach was established. It took advantage of the efficient full-information acquisition of ISF-MS1 (SID: 50 V), the high specificity of mass tag (NL: 46.0055 Da)-induced MS2 fragmentation, and the substructure fragmentation of product ion scan-MS3. We could characterize 216 carboxyl-free ginsenosides, and 21 thereof were potentially diagnostic for the species differentiation. Conclusively, sorted and untargeted characterization of the carboxyl-free ginsenosides was achieved by the established NL-PIS approach. In contrast to the conventional NL or PIS-based survey scan strategies, the high-accuracy MSn data obtained can enable more reliable identification of ginsenosides.

2.
Oxid Med Cell Longev ; 2019: 6859757, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31687084

RESUMO

Oxidative stress is the major cause of atherosclerosis and cardiovascular diseases. This cross-sectional study is aimed at determining if parallel serum markers of oxidative stress are related to carotid intima-media thickness (IMT). We enrolled 134 participants with varied metabolic syndrome (Met-S) scores (zero, n = 21; one, n = 19; two, n = 27; three, n = 26; four, n = 25; five, n = 16). Biochemical profiles and potential oxidative stress biomarkers malondialdehyde (MDA) and uric acid were measured in fasting plasma. We found that carotid IMT positively correlated with both MDA and uric acid levels. Multivariate analysis revealed that both MDA (p < 0.05) and uric acid (p < 0.01) levels were significantly associated with carotid IMT in participants whose Met-S scores were ≥1 or ≥2. However, only uric acid (p < 0.01) levels were positively associated with carotid IMT in patients with metabolic syndrome. Linear regression model analysis revealed that the prediction accuracies for carotid IMT from MDA combined with uric acid and from a combination of MDA, uric acid, and Met-S score were 0.176 and 0.237, respectively. These were better than the predication accuracies from MDA (r 2 = 0.075) and uric acid (r 2 = 0.148) individually. These results suggest that measuring uric acid levels along with MDA biomarkers and Met-S scores may be a promising step in the development of an effective model for monitoring the severity of carotid IMT and atherosclerosis in the patients with metabolic syndrome.

3.
Environ Toxicol ; 2019 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-31566298

RESUMO

Galangin, a natural flavonol, has anti-inflammatory and antioxidative potential. However, the cytoprotective effects of galangin against oxidative-induced aging in human fibroblasts have not been well studied. IGF-1 signaling pathway is associated with the control of aging and longevity in human. The goal of this study was to investigate the effects of galangin on human skin fibroblast HS68 cells under H2 O2 exposure to induce aging. In this study, we demonstrate that galangin could decrease the levels of pro-inflammatory proteins and enhanced collagen formation through promoting the IGF-1R pathway. Furthermore, aging markers such as senescence-associated ß-galactosidase p53, p21Cip1/WAF1 , and p16INK4A were upregulated under H2 O2 exposure and galangin could reverse its effects. Taken together, these data indicated that anti-inflammatory and antiaging activities of galangin may be mediated through the IGF-1R signaling pathway. These findings may provide the evidence for galangin to develop as an antiwrinkle product on human skin.

4.
J Cell Physiol ; 2019 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-31584202

RESUMO

Cardiac hypertrophy is a common phenomenon observed in progressive heart disease associated with heart failure. Insulin-like growth factor receptor II (IGF-IIR) has been much implicated in myocardial hypertrophy. Our previous studies have found that increased activities of signaling mediators, such as calcium/calmodulin-dependent protein kinase II (CaMKII) and calcineurin induces pathological hypertrophy. Given the critical roles played by CaMKII and calcineurin signaling in the progression of maladaptive hypertrophy, we anticipated that inhibition of CaMKII and calcineurin signaling may attenuate IGF-IIR-induced cardiac hypertrophy. The current study, therefore, investigated the effects of IGF-IIR activation on the CaMKII and calcineurin signaling and whether the combinatorial inhibition of the CaMKIIδ and calcineurin signaling could ameliorate IGF-IIR-induced pathological hypertrophy. In the present study, we induced IGF-IIR through the cardiomyocyte-specific transduction of IGFIIY27L via adeno-associated virus 2 (AAV2) to evaluate its effects on cardiac hypertrophy. Interestingly, it was observed that the activation of IGF-IIR signaling through IGFIIY27L induces significant hypertrophy of the myocardium and increased cardiac apoptosis and fibrosis. Moreover, we found that Leu27 IGF-II significantly induced calcineurin and CaMKII expression. Furthermore and importantly, the combinatorial treatment with CaMKII and calcineurin inhibitors significantly alleviates IGF-IIR-induced hypertrophic responses. Thus, it could be envisaged that the inhibition of IGF-IIR may serve as a promising candidate for attenuating maladaptive hypertrophy. Both calcineurin and CaMKII could be valuable targets for developing treatment strategies against hypertension-induced cardiomyopathies.

5.
J Am Heart Assoc ; 8(20): e012138, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31576777

RESUMO

Background Elevated levels of an endogenous Na/K-ATPase inhibitor marinobufagenin accompany salt-sensitive hypertension and are implicated in cardiac fibrosis. Immunoneutralization of marinobufagenin reduces blood pressure in Dahl salt-sensitive (Dahl-S) rats. The effect of the anti-marinobufagenin monoclonal antibody on blood pressure, left ventricular (LV) and renal remodeling, and gene expression were investigated in hypertensive Dahl-S rats. Methods and Results Dahl-S rats were fed high NaCl (8%, HS; n=14) or low NaCl (0.1%, LS; n=14) diets for 8 weeks. Animals were administered control antibody (LS control antibody, LSC; HS control antibody, HSC; n=7 per group) or anti-marinobufagenin antibody once on week 7 of diet intervention (n=7 per group). Levels of marinobufagenin, LV, and kidney mRNAs and proteins implicated in profibrotic signaling were assessed. Systolic blood pressure was elevated (211±8 versus 133±3 mm Hg, P<0.01), marinobufagenin increased 2-fold in plasma (P<0.05) and 5-fold in urine (P<0.01), LV and kidney weights increased, and levels of LV collagen-1 rose 3.5-fold in HSC versus LSC. Anti-marinobufagenin antibody treatment decreased systolic blood pressure by 24 mm Hg (P<0.01) and reduced organ weights and level of LV collagen-1 (P<0.01) in hypertensive Dahl salt-sensitive rats with anti-marinobufagenin antibody versus HSC. The expression of genes related to transforming growth factor-ß-dependent signaling was upregulated in the left ventricles and kidneys in HSC versus LSC groups and became downregulated following administration of anti-marinobufagenin antibody to hypertensive Dahl-S rats. Marinobufagenin also activated transforming growth factor-ß signaling in cultured ventricular myocytes from Dahl-S rats. Conclusions Immunoneutralization of heightened marinobufagenin levels in hypertensive Dahl-S rats resulted in a downregulation of genes implicated in transforming growth factor-ß pathway, which indicates that marinobufagenin is an activator of profibrotic transforming growth factor-ß-dependent signaling in salt-sensitive hypertension.

7.
J Formos Med Assoc ; 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31624009

RESUMO

The incidence and prevalence of inflammatory bowel disease have been increasing for decades and IBD has become a worldwide disease. Epidemiology studies demonstrated higher incidence rates in the more westernized countries. The change of habitual diets in these countries is perceived as the reason for the development of IBD. Besides, molecular biological studies showed some pathogenic substances produced after digestion of daily diet decrease the diversity of intestinal microbiota and cause dysbiosis of microbiome. Then, chronic inflammation occurs in some genetically susceptible subjects and IBD developed. As a result, many researchers started to investigate the potential therapeutic effects of nutrients and dietary intervention on the clinical course and pathogenesis of IBD. Carbohydrates, fats, proteins and fibers are investigated and their molecular roles in the inflammatory process are discovered gradually. The undigested carbohydrates are proved to cause overgrowth of colonic bacteria and inflammation occurs by altering colonic microbiome. ω-3 poly-unsaturated fatty acids are more favored over ω-6 poly-unsaturated fatty acids due to its less pro-inflammatory properties. High fibers produce more short-chain fatty acids in colon and facilitate the diversity of colonic microbiota. Moreover, some dietary interventions were designed and studied with promising results. Low FODMAP is recommended in IBS and is also suggested in patients of IBD with IBS-like symptoms. Specific Carbohydrate Diet was designed for celiac disease at first and is proved to be effective to decrease inflammation and to induce remission by decreasing non-digested carbohydrates into colon. Exclusive Enteral Nutrition has been investigated and is suggested to be the first line of management in pediatric CD in many literatures. Paleolithic diet and semi-vegetarian diet are evaluated and might be beneficial in some clinical settings. These findings are promising but limited to the evidence without high quality level. Some more well-designed studies with randomization and double-blind are needed and the primary endpoints should be more focused on the decrease of inflammation in pathology and mucosal healing in endoscopy instead of relief of the symptoms.

8.
J Nat Prod ; 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31646857

RESUMO

Three new labdane-type diterpenoids, 6α-O-isovalerylnidorellol (1), (12S)-blumdane (2), and (12R)-epiblumdane (3), and three new bisnorditerpenoids, 6α-O-(3-methyl-2-butenoyl)sterebin A (5), 6α-O-angeloylsterebin A (6), and 6α-O-isovalerylsterebin A (7), plus 17 known compounds were isolated from Blumea aromatica. Their structures of the new compounds were proposed by detailed spectroscopic analysis. The absolute configuration at C-12 of blumdane (2) was determined by the modified Mosher's method. The anti-inflammatory and anti-immunosuppressive effects of these isolated compounds were assessed. Compounds 9, 16, and 23 (at 40 µM) showed a slight suppression of TNF-α production, but no or little effect on the expression of PD-L1 in granulocytic myeloid-derived suppressor cells was observed for all test compounds.

9.
Viruses ; 11(10)2019 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-31627264

RESUMO

Enzootic nasal tumor virus (ENTV) has two types, ENTV-1 in sheep and ENTV-2 in goats, respectively. In China, the incidence of ENTV-2 related diseases has increased year by year. In this study, we reported an outbreak of ENTV-2 in a commercial goat farm in Qingyuan city, Guangdong province, southern China. A full-length genome of ENTV-2 (designated GDQY2017), with 7479 base pairs, was sequenced. Although GDQY2017 shared the highest nucleotide identity with a Chinese ENTV-2 isolate (ENTV-2CHN4, GenBank accession number KU258873), it possesses distinct genome characteristics undescribed, including a non-continuous 21-nucleotide insertion in the gag gene and a non-continuous 12-nucleotide deletion in the env gene. Notably, most of these indel nucleotide sequences were originated from a Chinese jaagsiekte sheep retrovirus (JSRV) isolate (GenBank accession number DQ838494). In the gag and env genes, GDQY2017 was phylogenetically related to those Chinese ENTV-2 isolates and a Chinese JSRV isolate (DQ838494). For GDQY2017-like viruses, more surveillance work should be made to explain their pathogenicity in goat herds. To our knowledge, this study represents the first to demonstrate the circulating pattern of ENTV-2 in Guangdong province, China, which will help to better understand the epidemiology and genetic diversity of ENTV-2.

10.
Chemistry ; 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31638288

RESUMO

A series of donor-acceptor-donor triazine-based molecules with thermally activated delayed fluorescence (TADF) properties were synthesized to obtain highly efficient blue-emitting OLEDs with non-doped emitting layer (EML). The targeted molecules use a triazine core as the electron acceptor, and a benzene ring as the conjugated linker with different electron donors to alternate the energy level of HOMO to further tune the emission color. The introduction of long alkyl chains on the triazine core inhibits the unwanted intermolecular D-D/A-A type π-π interactions, resulting in the intermolecular D-A charge transfer. The weak aggregation-caused quenching (ACQ) effect caused by the suppressed intermolecular D-D/A-A type π-π interaction further enhances the emission. The crowded molecular structure allows the electron donor and acceptor to be nearly orthogonal, thereby reducing the energy gap between triplet and singlet excited states (ΔEST). As a result, blue-emitting devices with TH-2DMAC and TH-2DPAC non-doped EML showed satisfactory efficiencies of 12.8% and 15.8%, respectively, which is one of the highest EQEs reported in the blue TADF emitters (λpeak < 475 nm), demonstrating that our tailored molecular designs are promising strategies to endow OLEDs with excellent EL performances.

11.
Int J Mol Med ; 44(6): 2123-2132, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31661126

RESUMO

Skin cancer is one of the most common cancers worldwide. Melanoma accounts for ~5% of skin cancers but causes the large majority of skin cancer­related deaths. Recent discoveries have shown that the mitogen­activated protein kinase (MAPK) signaling pathway is critical for melanoma development and progression. Many oncogenic pathways that cause melanoma tumorigenesis have been identified, most of which are due to RAF/MEK/ERK (MAPK) pathway activation. However, the precise role of p38 remains unclear. Using specific short hairpin (sh) RNA to silence p38α and p38ß, the present findings demonstrated that p38α was a crucial factor in regulating cell migration in the A375 melanoma cell line. Silencing p38α downregulated the expression of epithelial­mesenchymal transition markers, such as matrix metallopeptidase (MMP) 2, MMP9, twist family bHLH transcription factor 1, snail family transcriptional repressor 1 and vimentin, while mesenchymal­epithelial transition markers, such as E­cadherin, were upregulated. Of note, the results also demonstrated that p38α silencing impaired vascular endothelial growth factor expression, which regulates tumor angiogenesis. Furthermore, p38α knockdown inhibited cell proliferation in melanoma cells. In addition, silencing p38α induced senescence­like features, but not cell cycle arrest. Expression of the senescence markers p16, p21, p53 and ß­galactosidase was upregulated, and an increase in the number of senescence­associated ß­galactosidase­positive cells was observed in a p38α knockdown stable clone. However, no significant difference was found between control and p38ß stable knockdown cells. Taken together, the present results suggested that p38α knockdown impaired migration and proliferation, and increased senescence, in A375 melanoma cells. However, p38ß may not be involved in melanoma tumorigenesis. Therefore, targeting p38α may be a valuable approach towards inhibiting tumor growth and metastasis in patients with melanoma.

12.
Bioorg Chem ; 93: 103256, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31586706

RESUMO

A phytochemical investigation to obtain chemical components with potential anti-inflammatory activity from E. hylonoma led to the isolation of nine new ent-isopimarane diterpenoids (1 and 3-10), a new ent-rosane diterpenoid (11), along with eight known ones (2 and 12-18) using various chromatographic techniques. Compounds 3, 4, 5, and 10 were rare examples of the epoxy-ent-isopimarane. The structures of these new compounds were confirmed by extensive spectroscopic data, crystal X-ray diffraction analysis, and electronic circular dichroism. And the isolates were evaluated for their inhibitory effects on nitric oxide production induced by lipopolysaccharide in RAW 264.7 cells. The results showed that compounds 2 and 12 exhibited noteworthy inhibitory effects against NO production with IC50 values of 7.12 and 12.73 µM, respectively, which were better than positive control (IC50 = 41.41 µM). The possible mechanism that compounds 2 and 12 could inhibit NO production was investigated by the Western blotting experiments.

13.
World Neurosurg ; 133: 275-277, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31629145

RESUMO

We report a rare case of cervicothoracic intramedullary and extramedullary lipoma. Complete resection of the extramedullary lipoma and almost complete resection of the intramedullary lipoma were performed using a microscope, followed by posterior fusion and internal fixation from C4-T2 to maintain the stability of the cervicothoracic junction. Despite the high risk, it was still necessary to perform the decompression surgery and the surgical results were favorable.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31511971

RESUMO

PURPOSE: The role of lymph node ratio (LNR, ratio of metastatic to examined nodes) in the staging of multiple human malignancies has been reported. We aim to evaluate its value in salivary gland cancer (SGC). METHODS: Records of SGC patients from Surveillance, Epidemiology, and End Results database (SEER, training set, N = 4262) and Fudan University Shanghai Cancer Center (FUSCC, validating set, N = 154) were analyzed for the prognostic value of LNR. Kaplan-Meier survival estimates, the Log-rank χ2 test and Cox proportional hazards model were used for univariate and multivariate analysis. Optimal LNR cutoff points were identified by X-tile. RESULTS: Optimal LNR cutoff points classified patients into four risk groups, R0, R1 (≤ 0.17), R2 (0.17-0.56) and R3 (> 0.56), corresponding to 5-year cause-specific survival in SEER patients of 88.6%, 57.2%, 53.1% and 39.7%, disease-free survival in FUSCC patients of 69.2%, 63.3%, 34.6% and 0%, and disease-specific survival in FUSCC patients of 92.3%, 90.0%, 71.4% and 0%, respectively. Compared with TNM staging, TNM + R staging showed smaller AIC values and higher C-index values in the Cox regression model in both patient sets. CONCLUSIONS: LNR classification should be considered as a complementary system to TNM staging and LNR classification based clinical trials deserve further research.

15.
Ying Yong Sheng Tai Xue Bao ; 30(9): 2933-2940, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31529867

RESUMO

Maintaining forest structural diversity is generally considered as an effective way to preserve forest stability and biodiversity. The spatial structure characteristics of the dominant tree species in a climax community were investigated in a primary mixed broadleaved Korean pine (Pinus koraiensis) forest in a mountainous area of eastern Liaoning. Stand spatial structure parameters were determined based on the relationships among neighboring trees. The climax communities were used as a theoretical reference for optimizing the spatial structure of a low-quality secondary forest and monoculture plantation. The diameter distribution of the trees in the pine forest exhibited an inverse J-shape, indicating that understory regeneration was relatively good and with certain proportion of large-diameter trees. The main tree species were randomly distributed across the whole plot (=0.507) and in an intensively mixed state (=0.82). An average DBH comparison of trees in the stand indicated that they were at a intermediate status (=0.506). There was a differentiation among different dominances along the high intensity mixed dimension in the stand, indicating an optimal distribution of understory trees and the rational utilization of resources. Trees in the small diameter category were at a state of complete compression, while canopy trees were at a state of complete dominance in terms of their vertical space. Individuals of each dominant tree species were randomly scattered, with a random pattern of individuals throughout the climax community.


Assuntos
Florestas , Pinus , Árvores , China , República da Coreia
16.
Sci Transl Med ; 11(511)2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31554736

RESUMO

Idiopathic pulmonary fibrosis (IPF) is a progressive fibrotic lung disease where invasive pulmonary myofibroblasts secrete collagen and destroy lung integrity. Here, we show that interleukin-11 (IL11) is up-regulated in the lung of patients with IPF, associated with disease severity, and IL-11 is secreted from IPF fibroblasts. In vitro, IL-11 stimulates lung fibroblasts to become invasive actin alpha 2, smooth muscle-positive (ACTA2+), collagen-secreting myofibroblasts in an extracellular signal-regulated kinase (ERK)-dependent, posttranscriptional manner. In mice, fibroblast-specific transgenic expression or administration of murine IL-11 induces lung myofibroblasts and causes lung fibrosis. IL-11 receptor subunit alpha-1 (Il11ra1)-deleted mice, whose lung fibroblasts are unresponsive to profibrotic stimulation, are protected from fibrosis in the bleomycin mouse model of pulmonary fibrosis. We generated an IL-11-neutralizing antibody that blocks lung fibroblast activation downstream of multiple stimuli and reverses myofibroblast activation. In therapeutic studies, anti-IL-11 treatment diminished lung inflammation and reversed lung fibrosis while inhibiting ERK and SMAD activation in mice. These data prioritize IL-11 as a drug target for lung fibrosis and IPF.

17.
Chem Commun (Camb) ; 55(77): 11634-11637, 2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31508621

RESUMO

Ultrathin 2D nickel(II) (Ni2+) and imidazole (Im) based zeolitic imidazolate framework Ni(Im)2 nanosheets are reported as exceptional efficient electrocatalysts for the electrocatalytic CO2 reduction reaction. Five nanometre thick nanosheets have a higher faradaic efficiency of 78.8% and a surface active site density of 1.68 × 10-7 mol cm-2, which is superior to those of thicker nanosheets and bulk Ni(Im)2.

18.
J Nat Prod ; 82(9): 2568-2579, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31503485

RESUMO

Thirteen new labdane-type diterpenoids 1-6, 9-11, 13, 14, 18, and 19 and seven known ones were isolated from the aerial parts of Leonurus japonicus. Compounds 1-5 represent rare examples of labdane-type diterpenoids, of which compounds 1-4 carry an N-chain linked at C-7 in their B-ring and compound 5 featured an α,ß-unsaturated-γ-lactam moiety. The structures and absolute configurations of these new diterpenoids were characterized by a combination of spectroscopic techniques, X-ray crystallography, electronic circular dichroism, and calculated specific rotations. The plant-growth regulatory activity of these compounds on the growth of the roots and shoots of Lactuca sativa and Lolium perenne seedlings were evaluated. Compound 3 showed a broad-spectrum inhibitory activity with the inhibition rates ranging from 60 to 83.5% at a concentration of 200 µg/mL, which were as active as those of glyphosate. Compound 8 had a selective inhibitory activity against the growth of the roots of L. perenne seedlings with an inhibition rate of 81.7%. However, compounds 11 and 16 exhibited significant stimulation effects on the roots of L. sativa with stimulation rates of 59.8 and 65.3%, respectively. In addition, compounds 3 and 8 exhibited inhibitory effects on the germination of L. perenne seeds.

19.
Int J Mol Sci ; 20(17)2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31480672

RESUMO

Cardiovascular diseases have a high prevalence worldwide and constitute the leading causes of mortality. Recently, malfunctioning of ß-catenin signaling has been addressed in hypertensive heart condition. Ang-II is an important mediator of cardiovascular remodeling processes which not only regulates blood pressure but also leads to pathological cardiac changes. However, the contribution of Ang-II/ß-catenin axis in hypertrophied hearts is ill-defined. Employing in vitro H9c2 cells and in vivo spontaneously hypertensive rats (SHR) cardiac tissue samples, western blot analysis, luciferase assays, nuclear-cytosolic protein extracts, and immunoprecipitation assays, we found that under hypertensive condition ß-catenin gets abnormally induced that co-activated LEF1 and lead to cardiac hypertrophy changes by up-regulating the IGF-IIR signaling pathway. We identified putative LEF1 consensus binding site on IGF-IIR promoter that could be regulated by ß-catenin/LEF1 which in turn modulate the expression of cardiac hypertrophy agents. This study suggested that suppression of ß-catenin expression under hypertensive condition could be exploited as a clinical strategy for cardiac pathological remodeling processes.

20.
Opt Express ; 27(14): 19348-19358, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31503695

RESUMO

Direct epitaxial growth of O-band InAs/GaAs quantum-dot laser on Si substrates has been rapidly developing over the past few years. But most of current methodologies are not fully compatible with silicon-on-insulator (SOI) technology, which is the essential platform for silicon photonic devices. By implementing an in situ III-V/Si hybrid growth technique with (111)-faceted Si hollow structures, we demonstrate the first optically pumped InAs/GaAs quantum-dot microdisk laser on SOI substrates grown by molecular beam epitaxy (MBE). The microdisk laser on SOI is characterized with threshold pump power as low as 0.39 mW and a Q factor of 3900 at room temperature. Additionally, the compared device performance of InAs quantum-dot microdisk lasers on GaAs, Si (001) and SOI are simultaneously studied with identical epi-structures.

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