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1.
Artigo em Inglês | MEDLINE | ID: mdl-31472960

RESUMO

Previous studies reported increased expression and activity of neutrophil elastase (NE) in NASH. However, the role of NE in nonalcoholic steatohepatitis (NASH) remained unclear. Wild type (WT) and NE knockout (NE KO) mice were fed with western diet (WD) for 24 weeks to establish NASH model. The severity of liver injury in NASH mice was assessed by biochemical analysis, liver triglyceride (TG) quantitation and histological scoring. The gene and protein expression was detected by quantitative real-time PCR, immunohistochemical and immunofluorescence staining (IHC/IF) and western blot analysis. After 24 weeks, WD induced WT (WD-WT) mice had significantly up-regulated NE protein in the liver. Moreover, body weight, liver/body weight, serum and hepatic TG, liver histological score, and hepatic inflammatory factors expression were significantly higher in WD-WT mice than those in low fat diet (LFD) induced WT mice, and these effects were markedly improved by NE KO. In addition, we found incereased expression of ceramides and serine palmitoyltransferase subunit 2 (SPT2) in WD-WT mice could be reversed by NE KO. Up-regulating expression of ceramides and SPT2 by active NE treatment was also found in mice primary hepatocytes. Collectively, these findings indicated that NE KO ameliorated WD induced NASH, and this beneficial effect was due, at least in part, to the potential of NE in regulating hepatic ceramides metabolism.

2.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 41(4): 457-463, 2019 Aug 30.
Artigo em Chinês | MEDLINE | ID: mdl-31484606

RESUMO

To systematically evaluate the risks of cardiocerebral vascular events in patients with primary biliary cholangitis(PBC). Methods We carried out a Meta analysis by RevMan 5.3 software to investigate literatureon the risk of cardiocerebral vascular events in patients with PBC and controls. Results Compared with non-PBC controls,PBC patients had significantly higher risk of coronary events(RR=1.56,P=0.0002);however,the risk of cerebrovascular events showed no significant difference between these two groups(RR=1.01,P=0.94).Subgroup analysis demonstrated a significantly lower risk of transient ischemic attack or carotid stenosis in PBC patients(RR=0.63,P=0.03);however,there was no significant difference in the risk of stroke(RR=1.11,P=0.40). Conclusion Patients with PBC have an increased risk of coronary events but may have a lower risk of transient ischemic attack or carotid stenosis.

3.
PLoS One ; 14(9): e0222041, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31490980

RESUMO

Tinnitus and hearing impairment are prevalent among headache patients. This study aims to investigate the risk of tinnitus, sensorineural hearing impairment, and sudden deafness in patients with non-migraine headache. Participants included 43 294 patients with non-migraine headache (non-migraine headache cohort) and 173 176 patients with no headache of any type (control cohort) frequency-matched with respect to 10-year age interval and sex from the Longitudinal Health Insurance Database 2005 of the Taiwan National Health Insurance Research Database. The mean age of the non-migraine headache cohort was 28.4 ± 14.9 years, and 58.5% of this cohort was male. The incidence rates of tinnitus, sensorineural hearing impairment, and sudden deafness were compared between cohorts using the Kaplan-Meier method with the log-rank test. A Cox proportional hazard model was used to examine the association of tinnitus, sensorineural hearing impairment, and sudden deafness with non-migraine headache, with adjustment for all covariates. The combined risk of either tinnitus, sensorineural hearing impairment, or sudden deafness was higher in the non-migraine headache cohort than in the control cohort (adjusted odds ratio [aHR], 2.73; 95% confidence interval [95% CI], 2.62-2.84; p < 0.0001). Subgroup analysis showed that patients in the non-migraine headache cohort were at significantly higher risk of developing tinnitus (aHR, 3.05; 95% CI, 2.91-3.19; p < 0.0001), sensorineural hearing impairment (aHR, 1.89; 95% CI, 1.74-2.05; p < 0.0001), and sudden deafness (aHR, 2.14; 95% CI, 1.77-2.59; p < 0.0001) than were controls. In this population-based study, the risks of tinnitus, sensorineural hearing impairment, and sudden deafness were found to be significantly higher in patients with non-migraine headache than in those without headache.

4.
Nutrients ; 11(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31491937

RESUMO

Because of its high prevalence worldwide, osteoporosis is considered a serious public health concern. Many known risk factors for developing osteoporosis have been identified and are crucial if planning health care needs. Recently, an association between uric acid (UA) and bone fractures had been explored. Extracellular UA exhibits antioxidant properties by effectively scavenging free radicals in human plasma, but this benefit might be disturbed by the hydrophobic lipid layer of the cell membrane. In contrast, intracellular free oxygen radicals are produced during UA degradation, and superoxide is further enhanced by interacting with NADPH oxidase. This intracellular oxidative stress, together with inflammatory cytokines induced by UA, stimulates osteoclast bone resorption and inhibits osteoblast bone formation. UA also inhibits vitamin D production and thereby results in hyper-parathyroidism, which causes less UA excretion in the intestines and renal proximal tubules by inhibiting the urate transporter ATP-binding cassette subfamily G member 2 (ABCG2). At normal or high levels, UA is associated with a reduction in bone mineral density and protects against bone fracture. However, in hyperuricemia or gout arthritis, UA increases bone fracture risk because oxidative stress and inflammatory cytokines can increase bone resorption and decrease bone formation. Vitamin D deficiency, and consequent secondary hyperparathyroidism, can further increase bone resorption and aggravated bone loss in UA-induced osteoporosis.

5.
Plant Biotechnol J ; 2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31487419

RESUMO

Understanding the genetic basis underlying its agronomic traits will provide critical molecular insights for alfalfa breeding. Nine agronomic traits were characterized across 322 alfalfa genotypes in three consecutive years. Phenotypic data analysis revealed that all 9 traits were significantly influenced by genotype and were of variable heritability. A total of 44,757 SNPs was identified and uniquely physically mapped to the Medicago truncatula reference genome. Population structure analysis showed that the entire collection could be divided into two subpopulations consistent with their geographic origins. Genome-wide association analysis identified 42 significant associated markers with agronomic traits. Two candidate genes associated with the SNPs were also identified, cloned and characterized transgenically in the model plant Arabidopsis thaliana. Overexpression of the gene MsACR11 in A. thaliana increased plant height compared with the wild-type. Quantitative reverse transcription polymerase chain reaction analysis results showed that MsACR11 up-regulated the transcription of GLN2, which encodes glutamine synthetase 2. The gene MsPB1 increased plant branching when overexpressed in A. thaliana. Taken together, the results of our study demonstrate that integrating GBS and GWAS can be a powerful approach for dissecting agronomic traits in alfalfa, and the results will be valuable for further characterization of candidate genes and to assist in alfalfa breeding. This article is protected by copyright. All rights reserved.

6.
J Phys Condens Matter ; 31(48): 485708, 2019 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-31489845

RESUMO

We report the influence of Mn dopant on magnetic properties of Zn0.95Mn0.05O (ZMO)/Al2O3(0 0 0 1) hetero-epitaxial systems grown by using pulsed-laser deposition. The room temperature (RT) intrinsic ferromagnetic (FM) ordering verified by superconducting quantum interference device magnetometer and x-ray magnetic circular dichroism spectrum of Mn L 2,3 edges is ascribed to the substitutional Mn atoms in the Zn site of ZnO. Mn in ZMO has a tetrahedral local symmetry instead of the octahedral symmetry of MnO, after verifying the absence of the Mn-related impurities or clusters in ZMO epitaxial film by Mn K-edge and Zn K-edge x-ray absorption spectroscopy spectrum, as well as the analysis of long-range structural ordering on Renninger scan of forbidden (0 0 0 5) reflection in x-ray diffraction, transmission electron microscopy and Raman spectrum. Comparison of x-ray absorption spectra of ZMO with those of ZnO epilayers at O K-, Zn K-, and L 3-edges indicates that the substitution of the Zn site with Mn enhances the charge-transfer (CT) transition and the presence of Zn vacancies (VZn) also dominate the photoluminescence (PL) spectrum, implying that the formation of numerous VZn defects plays an important role in activating FM interactions. The strong CT effect and the existence of high-density VZn suggest that the intrinsic RT FM ordering of insulating ZMO is a result of the formation of the bound magnetic polarons (BMPs) that interact with each other via intermediate magnetic impurities.

7.
DNA Cell Biol ; 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31483163

RESUMO

Multiple studies have shown that cancer-specific alternative splicing (AS) alterations are associated with clinical outcome. In this study, we aimed to profile prognostic AS signatures for pancreatic ductal adenocarcinoma (PDAC). We integrated the percent-spliced-in (PSI) data of AS in 140 PDAC patients based on the Cancer Genome Atlas (TCGA) dataset. We identified overall survival (OS)-associated AS events using univariate Cox regression analysis. Then, prognostic AS signatures were constructed for OS and chemoresistance prediction using the least absolute shrinkage and selection operator (LASSO) method. We also analyzed splicing factors (SFs) regulatory networks by Pearson's correlation. We detected 677 OS-related AS events in 485 genes by profiling 10,354 AS events obtained from 140 PDAC patients. Gene functional enrichment analysis demonstrated the pathways enriched by survival-associated AS. The AS signatures constructed with significant survival-associated AS events revealed high performance in predicting PDAC survival and gemcitabine chemoresistance. The area under the receiver operator characteristic curve was 0.937 in training cohort and 0.748 in validation cohort at 2000 days of OS. Furthermore, we identified prognostic SFs (e.g., ESRP1 and HNRNPC) to build the AS regulatory network. We constructed AS signatures for OS and gemcitabine chemoresistance in PDAC patients, which may provide clues for further experiment-based mechanism study.

8.
Zool Res ; 40(5): 456-465, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31502428

RESUMO

Mountain Dragons of the genus Diploderma Hallowell, 1861 were recently resurrected from the paraphyletic genus Japalura sensu lato (Wang et al., 2019a). Despite the recent split, Diploderma still represents one of the most diverse groups of agamid lizard from Asia, including 25 species recognized currently, with most species found in China ((Wang et al., 2019a, 2019b). Although increasing attention has been paid to cryptic diversity within the genus in Southwest China during the past decade, most studies have focused on a single species complex, D. flaviceps, only (Manthey et al., 2012; Wang et al., 2015, 2016, 2017, 2019a), with few studies on other congeners that also have widespread distributions. One such example is D. dymondi (Boulenger, 1906).

9.
J Cell Biochem ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31478239

RESUMO

Pancreatic ductal adenocarcinoma (PDAC), a common malignancy originated from the digestive system worldwide, has a poor clinical outcome. SPOCK1 is a widely investigated member of the Ca2+ -binding proteoglycan family and functions as an essential driver in several cancers. However, the complex regulatory role of SPOCK1 in PDAC is unclear. Bioinformatics analysis predicted an interrelationship between increased SPOCK1 expression and the clinical characteristics of patients with PDAC. The SPOCK1 expression levels in fresh tissue samples were confirmed, and SPOCK1 expression was then knocked down by lentivirus-mediated short hairpin RNA. Cell proliferation, metastasis, and apoptosis were detected through Cell Counting Kit-8, colony formation assays, invasion and migration assays, flow cytometric analysis, quantitative real-time polymerase chain reaction, and Western blot experiment. On the basis of the Cancer Genome Atlas database, we found a significantly higher level of SPOCK1 in PDAC than in adjacent nontumor tissues. Patients with PDAC with high SPOCK1 expression exhibited shorter overall survival time, as well as disease-free survival time. The knockdown of SPOCK1 significantly decreased the proliferation and metastasis of PCNA-1 and MIA PaCa-2 cells. Moreover, the knockdown of SPOCK1 led to cell cycle arrest in G0/G1 phase and increased the proportion of apoptotic PDAC cells by regulating members of the caspase and Bcl-2 families. Our data proved that SPOCK1 is a critical regulator of tumor proliferation and metastasis in PDAC cells. Therefore, SPOCK1 might be a potential prognostic and therapeutic target molecule in PDAC.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31495492

RESUMO

BACKGROUND: Bladder cancer (BCa) is one of the most common urological malignancies. While Inositol-3-phosphate synthase 1 (ISYNA1) expression and function were largely unknown in BCa. We aimed to study the expression and role of ISYNA1 in bladder cancer and investigate its potential mechanisms via ingenuity pathway analysis (IPA). METHODS: ISYNA1 expression was quantified by qRT-PCR in bladder cancer cell lines as well as normal urothelial cell line. Knocking down ISYNA1 gene in BCa T24 cells was achieved by shRNA lentivirus transfection. MTT and Celigo assay were used to assess cell proliferation. Flow cytometry was applied to test cell cycle and apoptosis. In addition, IPA was performed using PrimeView™ Human Gene Expression Array. Imunohistochemistry (IHC) was performed in BCa patient tissue microarray to verify the association between ISYNA1 expression and patients' clinicopathological features. RESULTS: ISYNA1 was significantly upregulated in BCa samples vs. para-tumor tissues. Higher expression were significantly associated with tumor T stage and lymph node metastasis of bladder cancer patients. Similarly, it was elevated in BCa cell lines (5637 and T24) compared with SVHUC cells. Knocking down ISYNA1 significantly decreased proliferation, induced apoptosis and cell cycle arrest in T24 cells. Furthermore, IPA indicated that ISYNA1 was an important regulatory factors and related networks were involved in multiple functional processes. CONCLUSION: Taken together, current study suggest ISYNA1 promotes proliferation and inhibit apoptosis in bladder cancer cells, and its expression correlated with BCa patients' clinicopathological features. Thus, ISYNA1 may serve as a potential biomarker and therapeutic target for BCa patients.

11.
Plant Biotechnol J ; 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31498543

RESUMO

Prefoldin (PFD) is a group II chaperonin that is ubiquitously present in the eukaryotic kingdom. Six subunits (PFD1-6) form a jellyfish-like heterohexameric PFD complex and function in protein folding and cytoskeleton organization. However, little is known about its function in plant cell wall-related processes. Here, we report the functional characterization of a PFD gene from Populus deltoides, designated as PdPFD2.2 There are two copies of PFD2 in Populus and PdPFD2.2 was ubiquitously expressed with high transcript abundance in the cambial region. PdPFD2.2 can physically interact with DELLA protein RGA1_8g, and its subcellular localization is affected by the interaction. In P. deltoides transgenic plants overexpressing PdPFD2.2, the lignin syringyl/guaiacyl ratio was increased, but cellulose content and crystallinity index were unchanged. In addition, the total released sugar (glucose and xylose) amounts were increased by 7.6% and 6.1%, respectively, in two transgenic lines. Transcriptomic and metabolomic analyses revealed that secondary metabolic pathways, including lignin and flavonoid biosynthesis, were affected by overexpressing PdPFD2.2. A total of eight hub transcription factors (TFs) were identified based on TF binding sites of differentially expressed genes in Populus transgenic plants overexpressing PdPFD2.2. In addition, several known cell wall-related TFs, such as MYB3, MYB4, MYB7, TT8, and XND1, were affected by overexpression of PdPFD2.2. These results suggest that overexpression of PdPFD2.2 can reduce biomass recalcitrance and PdPFD2.2 is a promising target for genetic engineering to improve feedstock characteristics to enhance biofuel conversion and reduce the cost of lignocellulosic biofuel production.

12.
Clin Chim Acta ; 497: 189-196, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31377126

RESUMO

BACKGROUND: We investigated the characterization of the gut microbiome in Chinese patients with ankylosing spondylitis (AS) and healthy controls (HCs) and to explore the association ofbacteria communities with dietary factors and disease activity. METHODS: 16S ribosomal RNA gene sequencing was performed on fecal DNA isolated from stool samples in consecutive cross-sectional cohorts. Alpha and beta diversities were assessed using QIIME, and comparisons were performed using one-way ANOVA, Student's t-test, and SKN multiple range comparisons to examine differences between groups and a correlation network analysis was performed. RESULTS: We investigated 207 samples from 103 AS patients and 104 HCs. Alpha diversity was not significant difference in AS compared with HCs. For the community structure, Bacteroidetes was the most represented class. Megamonas, Dorea, and Blautia were significantly greater in AS than in HCs, whereas the abundance of Lachnospira, Ruminococcus, and Clostridium_XlVb was significantly lower in AS than in HCs. In addition, Specific gut microbiome was significantly correlated with disease activity and dietary factors. CONCLUSIONS: Our results suggest that the human gut microbiome of AS patients was clearly different from that of HCs and bacteria communities are associated with dietary factors and disease activity.

13.
ACS Appl Mater Interfaces ; 11(34): 31402-31410, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31381291

RESUMO

Increasing power density makes modern electronic devices and power equipment generate excess heat, which greatly restricts the applications of polymeric materials because of their poor thermal conductivity. In the present work, inspired by the structure and production process of millefeuille cakes, we show that electrostatic spraying of boron nitride nanosheets (BNNSs) onto electrospun poly(vinyl alcohol) (PVA) nanofibers can produce highly thermally conductive, electrically insulating, flexible, and lightweight nanocomposites via a scalable method of building a multilayer PVA/BNNS nanonetwork structure. The PVA/BNNS nanocomposites exhibit an ultrahigh in-plane thermal conductivity of 21.4 W/(m·K) at 22.2 vol % BNNS addition, realized by an orientated BNNS network structure with overlapping interconnections. The BNNS networks exhibit low thermal resistance and interfacial heat scattering between BNNSs. Moreover, for heat dissipation applications, the nanocomposites with an overlapping BNNS network show higher efficiency in dissipating hot spots than randomly dispersed BNNS or directly hot-pressed BNNS composites. These PVA/BNNS nanocomposites can be used as high-performance lateral heat spreaders in next-generation thermal management systems.

14.
Med Sci Monit ; 25: 6462-6473, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31461437

RESUMO

BACKGROUND High-mobility group box1 (HMGB1) is a cytokine that has been demonstrated to have an important role in inducing migration and homing of endothelial progenitor cells (EPCs) in the process of neovascularization during wound healing, but its specific mechanism remains elusive. The aim of this study was to investigate the effects of the HMGB-RAGE axis in EPC migration, as well as the underlying molecular mechanism responsible for these effects. MATERIAL AND METHODS EPCs were isolated from the mice and identified using flow cytometry and fluorescence staining. The effect of HMGB1 on the activity of EPCs was detected using the Cell Counting Kit-8 (CCK-8). Then, the migration of EPCs was detected by scratch wound-healing and cell migration assay. NO levels were analyzed by ELISA. The expression of p-PI3K, p-Akt, and p-eNOS was determined by Western blot analysis. RAGE expression was measured by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot analysis. F-actin was assessed by fluorescent staining. RESULTS The results showed that HMGB1 induced a concentration-dependent migration of EPCs, and the migration was RAGE-dependent. The migration could be almost completely blocked by PI3K inhibitors and eNOS inhibitor. HMGB1-RAGE upregulated the expression of p-Akt, p-eNOS, and p-ERK. We also demonstrated that the MEK/ERK signaling pathway is not involved in the EPC migration induced by HMGB1-RAGE. CONCLUSIONS These data demonstrate that HMGB1 activates RAGE and induces PI3K/Akt/eNOS signaling transduction pathway activation to promote EPC migration. Therefore, the HMGB1-RAGE axis plays an important role in the EPC migration process and may become a potential target in wound healing.

15.
J Cancer Res Ther ; 15(4): 813-817, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31436236

RESUMO

Aim: This study aimed to evaluate the feasibility, safety, and clinical efficacy of computed tomography (CT)-guided 125 I seed interstitial implantation in patients with secondary adrenal carcinoma. Materials and Methods: Twenty patients with secondary adrenal carcinoma received CT-guided 125 I seed interstitial implantation. A three-dimensional treatment planning system was used to calculate the dose distribution before 125 I seed interstitial implantation. CT scans were performed every 2 months after the treatment to evaluate local therapeutic efficacy according to the Response Evaluation Criteria in Solid Tumors. Results: The mean follow-up time was 23.65 months (5-102 months). The mean maximum tumor diameter was 34.16 ± 18.94 mm at the beginning of follow-up and 14.42 ± 24.07 mm at the end of follow-up. Eleven patients had complete response (CR), seven had partial response (PR), one had stable disease, and one had progressive disease. Local control rate (CR + PR) was 90% (18/20). The median survival time was 19 months (5-71 months). The 1-, 2-, 3-, and 5-year overall survival rates were 83.70%, 46.8%, 20.80%, and 20.80%, respectively. Conclusion: CT-guided 125 I radioactive seed interstitial implantation may be a feasible, safe, effective, and minimally invasive treatment for secondary adrenal carcinoma.

16.
Cancer Res ; 79(16): 4003-4008, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31362930

RESUMO

Metabolic reprogramming of cancer cells and the tumor microenvironment are emerging as key factors governing tumor growth, metastasis, and response to therapies including immune checkpoint inhibitors. It has been recognized that rapidly proliferating cancer cells, tumor-infiltrating lymphocytes, and vascular endothelial cells compete for oxygen and nutrients. Tumor cells and other cell types in the microenvironment not only compete for nutrients, but they also simultaneously produce immunosuppressive metabolites, leading to immune escape. In addition, commensal microbial metabolites can influence regulatory T cells and inflammation in the intestine, thus playing an essential role in cancer prevention or cancer promotion. In this review, we summarize recent advances on metabolic interactions among various cell types in the tumor microenvironment, with a focus on how these interactions affect tumor immunity. We also discuss the potential role of blood vessel metabolism in regulating immune cell trafficking and activation.

17.
BMJ Case Rep ; 12(8)2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31377716

RESUMO

Thymoma-associated multiorgan autoimmunity is a relatively new term to describe the rare paraneoplastic syndrome that complicates thymoma, which can involve the thyroid, liver and intestine in addition to the skin. The pathology often indicates a graft-versus-host-like pattern commonly observed in recipients of an allogeneic haematopoietic cell transplant. We report a case of type B2 and B3 thymoma with invasion to the lung and pleura in a patient who presented with oral lichen planus and graft-versus-host-like erythroderma. The cutaneous lesions improved after complete resection of the thymoma in combination with systemic glucocorticoids, which was subsequently complicated by cytomegalovirus pneumonitis.

18.
Environ Pollut ; 254(Pt A): 113023, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31404733

RESUMO

OBJECTIVE: Ambient particulate pollution, especially PM2.5, has adverse impacts on health and welfare. To manage and control PM2.5 pollution, it is of great importance to determine the factors that affect PM2.5 levels. Previous studies commonly focused on a single or several cities. This study aims to analyze the impacts of meteorological and socio-economic factors on daily concentrations of PM2.5 in 109 Chinese cities from January 1, 2015 to December 31, 2015. METHODS: To evaluate potential risk factors associated with the spatial and temporal variations in PM2.5 levels, we developed a Bayesian spatio-temporal model in which the potential temporal autocorrelation and spatial autocorrelation of PM2.5 levels were taken into account to ensure the independence of the error term of the model and hence the robustness of the estimated parameters. RESULTS: Daily concentrations of PM2.5 peaked in winter and troughed in summer. The annual average concentration reached its highest value (79 µg/m3) in the Beijing-Tianjin-Hebei area. The city-level PM2.5 was positively associated with the proportion of the secondary industry, the total consumption of liquefied petroleum gas and the total emissions of industrial sulfur dioxide (SO2), but negatively associated with the proportion of the primary industry. A reverse U-shaped relationship between population density and PM2.5 was found. The city-level and daily-level of weather conditions within a city were both associated with PM2.5. CONCLUSION: PM2.5 levels had significant spatio-temporal variations which were associated with socioeconomic and meteorological factors. Particularly, economic structure was a determinant factor of PM2.5 pollution rather than per capita GDP. This finding will be helpful for the intervention planning of particulate pollution control when considering the environmental and social-economic factors as part of the strategies.

19.
ACS Appl Mater Interfaces ; 11(35): 32127-32134, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31403281

RESUMO

The issue of contacts between the electrode and channel layer is crucial for wide-bandgap semiconductors, especially the ß-Ga2O3 due to its ultra-large bandgap (4.6-4.9 eV). It affects the device performance greatly and thus needs special attention. In this work, the high-performance ß-Ga2O3 nanobelt field-effect transistors with Ohmic contact between multilayer metal stack Ti/Al/Ni/Au (30/120/50/50 nm) and unintentionally doped ß-Ga2O3 channel substrate have been fabricated. The formation mechanism of Ohmic contacts to ß-Ga2O3 under different annealing temperatures in an N2 ambient is systematically investigated by X-ray photoelectron spectroscopy. It is revealed that the oxygen vacancies at the interface of ß-Ga2O3/intermetallic compounds formed during rapid thermal annealing are believed to induce the good Ohmic contacts with low resistance. The contact resistance (Rc) between electrodes and unintentionally doped ß-Ga2O3 reduces to ∼9.3 Ω mm after annealing. This work points to the importance of contact engineering for future improved ß-Ga2O3 device performance and lays a solid foundation for the wider application of ß-Ga2O3 in electronics and optoelectronics.

20.
Aging (Albany NY) ; 11(16): 6490-6502, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31425146

RESUMO

In this study, age related Cav1.3 expression in cochlea and auditory cortex of C57BL/6J male mice was evaluated. It was found that the expression of Cav1.3 in cochlea decreased with aging whereas this phenomenon was not observed in neuron of auditory cortex. The correlation between decreased expression of Cav1.3 and age-related hearing losses was studied in vitro, after Cav1.3 was knocked out, the rate of apoptosis of hair cells increased after being subjected to ROS stresses, accompanied with enhanced senescence. Further, Cav1.3 knock down also interfered with the electrophysiology of hair cells. The effect was further confirmed in vivo, after Cav1.3 knocked down by injection of AAV, hearing impairment was observed in C57BL/6J male mice subjected to senescence and this was accompanied by increased loss of hair cells in cochlea. The effect was further confirmed in 3D organ culture, increased loss of hair cells after Cav1.3 was knocked down under ROS stresses.Mechanistically, Cav1.3 knock out resulted in decreased intracellular calcium which subsequently reduced the inactivation of ROS from complex I, and finally resulted in increased intracellular ROS and enhanced senescence.Collectively, these findings confirmed that Cav1.3 could protect cells in auditory pathway from oxidative stresses, and decreased expression of Cav1.3 in auditory pathway could contribute to hearing losses by enhancement of calcium-mediated oxidative stress.

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